REVIEW | doi:10.20944/preprints202008.0554.v2
Subject: Biology, Anatomy & Morphology Keywords: Cooperation; Aggregative mulicellularity; Social Conflicts; Evolution; Dictyostelium discoideum
Online: 18 January 2021 (12:15:54 CET)
The ’social amoeba’ Dictyostelium discoideum, where aggregation of genet- ically heterogeneous cells produces functional collective structures, epitomizes social conflicts associated with multicellular organization. ’Cheater’ populations that have a higher chance – quantified by a positive spore bias – of surviving to the next generation are selectively advantaged. Their spread is thus expected to undermine collective functions over evolutionary times. In this review, we discuss the two main approaches adopted to conceptualize social conflicts in Dictyostelium discoideum: describing spore bias as a property of cell popula- tions (strains), or as a result of individual cell choices during the developmental process. These two points of view are often held equivalent and used inter- changeably. While the population-level view allows for more direct evolutionary inference, however, the cell-level interpretation reveals that such evolutionary predictions may be modified if developmental mechanisms, such as dependence on the environment and intrinsic unpredictability of cell fate choices, are taken into account. We conclude by proposing a set of open questions that in our opinion lie at the core of a multi-scale description of aggregative life cycles, where the formulation of predictive evolutionary models would include cell-level mechanisms responsible for spore bias alongside population-level descriptors of multicellular organization.
ARTICLE | doi:10.20944/preprints202101.0320.v1
Subject: Biology, Anatomy & Morphology Keywords: Boechera; Brassicaceae; CENH3; APOLLO; apomixis associated genes; cell division; apomeiosis
Online: 18 January 2021 (11:39:27 CET)
Apomictic plants (reproducing via asexual seeds), unlike sexual individuals, avoid meiosis and egg cell fertilization. Consequently, apomixis is very important for fixing maternal genotypes in the next plant generations. Despite the progress in the study of apomixis, molecular and genetic regulation of the latter remains poorly understood. So far APOLLO (Aspartate Glutamate Aspartate Aspartate histidine exonuclease) is the only described gene associated with apomixis in Boechera species. The centromere-specific histone H3 variant encoded by CENH3 gene is essential for cell division. Mutations in CENH3 disrupt chromosome segregation during mitosis and meiosis since the attachment of spindle microtubules to a mutated form of the CENH3 histone fails. This paper presents in silico characteristic of APOLLO and CENH3 genes, which may affect apomixis. Also, in this research we characterize the structure of CENH3, study expression levels of CENH3 and APOLLO in gynoecium/siliques of the natural diploid apomictic and sexual Boechera species at the stages of before and after fertilization. At the premeiotic stage, the expression level of CENH3 in the gynoecium of apomicts was two times lower than that of the sexual Boechera, it decreased in both species by the time of meiosis and increased after fertilization. By 1 DAP CENH3 expression started dropping in sexual B. stricta siliques and kept increasing in apomictic B. divaricarpa ones. That might indicate to a role of CENH3 in apomictic development in Boechera species. The expression levels of APOLLO also sharply decreased by the time of meiosis in gynoecium of both species; however, by 3 DAP, the level of APOLLO expression in siliques of apomicts was almost 1.5 times higher than that of the sexuals. While CENH3 was a single copy gene in all Boechera species, the APOLLO gene have several polymorphic alleles associated with sexual and apomictic reproduction in the Boechera genera. We also discuss polymorphism and phylogeny of the APOLLO and CENH3 genes.
Fri, 15 January 2021
Online: 15 January 2021 (13:14:15 CET)
Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) as the current coronavirus pandemic is an infectious disease that initially confirmed in China in late December 2019. In this study, we analyzed 131 complete sequences of SARS-CoV-2 from Asia. Our results show that there are fifteen major mutations in Asia which most of them are co-evolved. There were five groups based on co-mutations which three of them resulted in clade G including (241C>T, 3037C>T, 14408C>T, and 23403A>G), (28881G>A, 28882G>A, 28883G>C and 23403A>G) and (25563G>T and 23403A>G). Co-mutations in (8782C>T and 28144T>C) and (1397G>A, 28688T>C, 29742G>T and 11083G>T) were clustered in clade S and a new clade outside of GISAID classification, respectively. Sequences with a mutation in 26144G>T had low variability without any co-mutation which formed clade V. In this study, we showed that Most of the circulated viruses in Asia collected in five co-mutation groups which may affect the transmissibility and vaccine designing strategies.
REVIEW | doi:10.20944/preprints202009.0520.v2
Subject: Biology, Ecology Keywords: Biotic interactions; Ecological modeling; Plant facilitation; Plant community ecology; Spatial ecology; Theoretical ecology.
Online: 15 January 2021 (12:37:06 CET)
Ecologists use the net biotic interactions among plants as a major factor to predict other ecosystem features, such as species diversity, community structure, or plant atmospheric carbon uptake. By adopting this approach, ecologists have built a giant body of theory founded on observational evidence. However, growing evidence points out that this may not be the right approach. The literature addressing the biophysical mechanisms underlying the plant interactions is much scarcer. A rising number of scientists claim the need for a mechanistic understanding of plant interactions due to the limitations that a phenomenological approach raises both in empirical and theoretical studies. Scattered studies have recently taken such a mechanistic approach, but we still lack a general theoretical framework to study mechanistically plant interactions. In this review, we first recapitulate the elementary units of plant interactions, i.e., all the known biophysical processes affected by the presence of an influencing plant and the possible phenotypic responses of plants influenced by those processes. Second, we discuss how a net interaction between two plants emerges from the simultaneous effect of these elementary units. Third, we touch upon the spatial and temporal variability of the net interaction and discuss the links between this variability and the underlying biophysical processes. We conclude by discussing how to integrate these processes into a mechanistic framework for plant interactions that must necessarily focus on the individual scale and explicitly incorporate the spatial structure of the community and environmental factors: the plant interaction models (PIM). A PIM incorporates a pair or few plants interacting with their physical environment so that the biotic interaction is not imposed but emerges from the model. This type of model can provide concise, mechanistic hypotheses to be tested empirically. This review calls for a paradigm shift in the ecology of plant interactions, from the classic species interaction study towards a more mechanistic individual-level approach. It also presents a comprehensive foundation for studying the mechanisms underpinning the net interaction between two plants.
ARTICLE | doi:10.20944/preprints202101.0285.v1
Subject: Biology, Anatomy & Morphology Keywords: Acari; Ips sexdentatus; Ips acuminatus; Ips typographus; Pinus nigra; Pinus sylvestris; Picea abies; Turkey
Online: 15 January 2021 (12:09:12 CET)
Phoretic mites use bark beetles for transportation to new, suitable habitats. Some phoretic mites act as predators and parasitoids of the bark beetles’ immature stages, especially egg and early larval stages, and are potential agents for the biological control of scolytine forest pests. One of the most numerous and largest mite orders is Mesostigmata which live very frequently in relationships with other invertebrates. Many are found in association with various species of bark beetles. Here, a total of 41 specimens of different bark beetles of the genus Ips (I. acuminatus, I. sexdentatus and I. typographus) were studied for presence, species composition, and abundance of phoretic mites. The beetles were collected on dead wood and parts of tree bark of Pinus nigra, P. slyvestris and Picea abies in the Black Sea Mountains in Kastamonu and Artin Province of Turkey. A total of 9 mite species in 2 genera were found, including Dendrolaelaps quadrisetus, Ereynetes sp., Histiostoma piceae, Paraleius cf. leontonychus, Pleuronectocaeleno barbara., Proctolaelaps hystricoides, Schizostethus simulatrix, Trichouropoda lamellosa and Urobovella ipidis. All species and genera are identified for the first time within Turkish fauna.
REVIEW | doi:10.20944/preprints202101.0282.v1
Subject: Biology, Anatomy & Morphology Keywords: oligodendrogenesis; remyelination; hormones; steroids; peptides
Online: 15 January 2021 (08:25:46 CET)
Alterations in myelin, the protective and insulating sheath surrounding axons, affect brain function, as is evident in demyelinating diseases where the loss of myelin leads to cognitive and motor dysfunction. Recent evidence suggests that changes in myelination, including both hyper- and hypo-myelination, may also play a role in numerous neurological and psychiatric diseases. Protecting myelin and promoting remyelination is thus crucial for a wide range of disorders. Oligodendrocytes (OLs) are the cells that generate myelin, and oligodendrogenesis (OLgenesis), the creation of new OLs, continues throughout life and is necessary for myelin plasticity and remyelination. Understanding the regulation of OLgenesis and myelin plasticity within disease contexts is therefore critical for the development of novel therapeutic targets. In our companion manuscript , we review literature demonstrating that multiple hormone classes are involved in the regulation of OLgenesis under physiological conditions. The majority of hormones enhance OLgenesis, increasing oligodendrocyte precursor cell differentiation and inducing maturation and myelin production in OLs. Thus, hormonal treatments present a promising route to promote remyelination. Here, we review literature on hormonal regulation of OLgenesis within the context of disorders. We focus on steroid hormones, including glucocorticoids and sex hormones, peptide hormones such as insulin-like growth factor 1, and thyroid hormones. For each hormone, we describe whether they aid in OL survival, differentiation, or remyelination, and we discuss their mechanisms of action, if known. Several of these hormones have yielded promising results in both animal models and in human conditions; however, a better understanding of hormonal effects, interactions, and their mechanisms will ultimately lead to more targeted therapeutics for myelin repair.
REVIEW | doi:10.20944/preprints202101.0281.v1
Subject: Biology, Anatomy & Morphology Keywords: oligodendrogenesis; hormones; mechanisms; steroids; peptides
Online: 15 January 2021 (07:47:37 CET)
The brain’s capacity to respond to changing environments via hormonal signaling is critical to fine-tuned function. An emerging body of literature highlights a role for myelin plasticity as a prominent type of experience-dependent plasticity in the adult brain. Myelin plasticity is driven by oligodendrocytes (OLs) and their precursor cells (OPCs). OPC differentiation regulates the trajectory of myelin production throughout development, and importantly, OPCs maintain the ability to proliferate and generate new OLs throughout adulthood. The process of oligodendrogenesis (OLgenesis), the creation of new OLs, can be dramatically influenced during early development and in adulthood by internal and environmental conditions such as hormones. Here, we review the current literature describing hormonal regulation of OLgenesis within physiological conditions, focusing on several classes of hormones: steroid, peptide, and thyroid hormones. We discuss hormonal regulation at each stage of OLgenesis and describe mechanisms of action, where known. Overall, the majority of hormones enhance OLgenesis, increasing OPC differentiation and inducing maturation and myelin production in OLs. The mechanisms underlying these processes vary for each hormone but may ultimately converge upon common signaling pathways, mediated by specific receptors expressed across the OL lineage. However, not all of the mechanisms have been fully elucidated, and here, we note the remaining gaps in the literature, including the complex interactions between hormonal systems and with the immune system. In the companion manuscript in this issue , we discuss the implications of hormonal regulation of OLgenesis for neurological and psychiatric disorders characterized by white matter loss. Ultimately, a better understanding of the fundamental mechanisms of hormonal regulation of OLgenesis across the entire lifespan, especially in vivo, will progress both basic and translational research.
Thu, 14 January 2021
ARTICLE | doi:10.20944/preprints202101.0278.v1
Subject: Biology, Anatomy & Morphology Keywords: Ascorbic acid; Biochemicals; Micronutrients; Solanum melongena; Salinity
Online: 14 January 2021 (14:40:47 CET)
The experiments were designed to know the function of ascorbic acid against salinity on germination, different biochemical and micronutrients concentrations of Solanum melongena. Ascorbic acid was applied as foliar spray on leaves and given in roots through irrigation at 100 and 200 ppm to the plants growed in non saline, 60mM and 100mM salt stress conditions. Different biochemical parameters i.e. chlorophyll, carotenoids, carbohydratrates, protein and micro nutrients concentrations of Solanum melongena were observed under different salt stress concentrations from control (non-saline), 60mM NaCl and 100mM NaCl solutions. The rates of different biochemical parameters and micro nutrients concentrations exhibited decrease in saline media in comparison with their respective control while ascorbic acid used as a foliar spray and through irrigation in roots at the concentration of 100 ppm and 200 ppm resulted promotion in non saline control as compared with salt concentrations media. It was determined that chlorophyll concentration was decreased considerably under salt stress. Amongst micro nutrients ionic composition of Na, K and Na/K ratio resulted that plants treated with different NaCl concentrations at 60mM NaCl and 100mM salt concentrations showed increase in Na and K ions and ascorbic acid were used as a foliar spray and in roots showed decrease in Na and K ions. Overall from the outcomes of the study it was observed that salinity stress significantly decrease vegetative and reproductive parameters that could be improved with the using of ascorbic acid. Best concentration found were 200 ppm ascorbic acid contributed towards an increase in growth irrespective of non-saline and saline conditions. Based on these findings, ascorbic acid treatment helps in alleviating the negative effects of salinity.
Wed, 13 January 2021
BRIEF REPORT | doi:10.20944/preprints202101.0254.v1
Online: 13 January 2021 (14:49:44 CET)
Although working memory (WM) is crucial for intellectual abilities, not much is known about its brain underpinnings, especially the structural connectivity. We used diffusion tensor imaging (DTI) to look across the whole brain for the white matter integrity correlates of the individual differences in the reading span (verbal WM capacity during reading) in healthy adults. Right-handed healthy native Russian speakers (N = 47) underwent DTI on a 3T Philips Ingenia scanner. Verbal WM was assessed with the Daneman-Carpenter reading span test (Russian version). Fractional anisotropy maps from each participant were entered into the group tract-based spatial statistics analysis with the reading span as a covariate; the results were TFCE-corrected. Reading span positively correlated with the white matter integrity in several sites of the right hemisphere: the body and the splenium of corpus callosum; the posterior limb of internal capsule; posterior corona radiata; and superior parietal white matter. Although the left hemisphere is central for verbal processing, we revealed the important role of the right hemisphere white matter for the verbal WM capacity. Our finding indicates that larger verbal working memory span may originate from additional processing resources of the right hemisphere.
Subject: Biology, Animal Sciences & Zoology Keywords: intramuscular fat; prediction; image analysis; Bísaro pork
Online: 13 January 2021 (13:16:19 CET)
This work presents an analytical methodology to predict meat juiciness (discriminant semi-quantitative analysis using groups of intervals of intramuscular fat) and intramuscular fat (regression analysis) in Longissimus thoracis et lumborum (LTL) muscle of Bísaro pigs using as independent variables the animal carcass weight and parameters from color and image analysis. These are non-invasive and non-destructive techniques which allow development of rapid, easy and inexpensive methodologies to evaluate pork meat quality in a slaughterhouse. The proposed predictive supervised multivariate models were non-linear. Discriminant mixture analysis to evaluate meat juiciness by classified samples into three groups—0.6 to 1.1%; 1.25 to 1.5%; and, greater than 1.5%. The obtained model allowed 100% of correct classifications (92% in cross-validation with seven-folds with five repetitions). Polynomial support vector machine regression to determine the intramuscular fat presented R2 and RMSE values of 0.88 and 0.12, respectively in cross-validation with seven-folds with five repetitions. This quantitative model (model’s polynomial kernel optimized to degree of three with a scale factor of 0.1 and a cost value of one) presented R2 and RSE values of 0.999 and 0.04, respectively. The overall predictive results demonstrated the relevance of photographic image and color measurements of the muscle to evaluate the intramuscular fat, rarther than the usual time-consuming and expensive chemical analysis.
REVIEW | doi:10.20944/preprints202101.0238.v1
Subject: Biology, Anatomy & Morphology Keywords: Artificial reefs; design; building material; bio-monitoring; species diversity; European Atlantic
Online: 13 January 2021 (10:31:56 CET)
Artificial reefs have been deployed in multiple regions of the world for different purposes including habitat restoration and protection, biodiversity and fish stock enhancement, fisheries management and recreation. Artificial reefs can be a valuable tool for ecosystem protection and rehabilitation, helping mitigate the effects of anthropogenic impacts that we face today. However, knowledge on artificial reefs is unevenly distributed worldwide, with some regions having much more quality information available and published (e.g. European Mediterranean Sea area), while others, for instance the North-East Atlantic area, do not. Here, we provide a characterization of purposely built artificial reefs in North-East Atlantic area based on all available literature (i.e. research papers and reports), highlighting the needs and gaps that are vital for establishing future perspectives for artificial reef deployment and research. In the North-East Atlantic area, sixty-one purposely built artificial reefs have been deployed since 1970, mostly between the years 1990-2009, with Spain being the country with the highest number of artificial reefs. The most reported purpose for their deployment is fisheries productivity and habitat/species protection, although, most artificial reefs are multipurpose in order to maximise the benefits of a given financial investment. The majority of artificial reefs were submerged at < 50 m, mainly between 10-20 m of depth. The most used designs were cubic blocks and complex designs made by an array of combined shapes, which mostly consist of concrete (79%). From all the analysed data on artificial reefs, 67% of the cases reported surveys to assess biodiversity after the deployment. However, in 26% of those cases, data was not available. When data was available, only 31% of cases reported long-term biomonitoring surveys (3 years or more). Based upon these findings, we noticed a general lack of scientifically robust data, including records of species and abundance of both fish and invertebrates, as well as macroalgae. Preventing an adequate determination of the best balance between shape, construction material and bio-colonization. Critiques and suggestions are discussed in the light of current available data in order to perform more efficient research, evaluation and functioning of future artificial reefs.
Tue, 12 January 2021
REVIEW | doi:10.20944/preprints202101.0220.v1
Subject: Biology, Anatomy & Morphology Keywords: RAS oncogene; RAS signaling networks; RAS in human cancer; targeting RAS; computational modeling; personalized therapies
Online: 12 January 2021 (12:29:58 CET)
RAS oncogenes are amongst the most commonly mutated proteins in human cancers. They regulate a wide range of effector pathways that control cell proliferation, survival, differentiation, migration and metabolic status. Including aberrations in these pathways, RAS dependent signaling is altered in more than half of human cancers. Targeting mutant RAS proteins and their downstream oncogenic signaling pathways has been elusive. However, recent results comprising detailed molecular studies, large scale omics studies and computational modeling have painted a new and more comprehensive portrait of RAS signaling that helps us to understand the intricacies of RAS, how its physiological and pathophysiological functions are regulated, and how we can target them. Here, we review these efforts particularly trying to relate the detailed mechanistic studies with global functional studies. We highlight the importance of computational modeling and data integration to derive an actionable understanding of RAS signaling that will allow us to design new mechanism based therapies for RAS mutated cancers.
ARTICLE | doi:10.20944/preprints202101.0216.v1
Subject: Biology, Anatomy & Morphology Keywords: CBF4; Transcription factors; Cold tolerance; overexpression; cotton
Online: 12 January 2021 (10:54:56 CET)
Low temperature is a common biological abiotic stress in major cotton growing areas. Cold stress significantly affects the growth, yield and yield quality of cotton. Therefore, it is important to develop a more robust and cold stress tolerant cotton germplasms. Climate change and erratic climatic condition, plants have evolved various survival mechanisms, one of which induction of various stress responsive transcriptome factors, such as the C-repeat binding factor GthCBF4, which have been found to enhance cold tolerance in various plants. In this study detailed evaluation of the cotton C-repeat binding factor has been carried out. A total of29, 28, 25, 21, 30, 26 and 15 proteins encoded by the C-repeat binding factor were identified in G. herbaceum, G. arboreum, G. thurberi, G. raimondii, G. turneri, G. longicalyx and G. australe, respectively. Phylogeny evaluation revealed that the proteins were grouped into seven clades, with clade 1 and 6 being the largest. Moreover, majority of the proteins encoded by the genes were predicted to be located within. the nucleus, while some are distributed in other parts of the cell. Based on the transcriptome and RT-qPCR analysis, Gthu17439 (GthCBF4) was highly upregulated and was further validated through forward genetics. The Gthu17439 (GthCBF4) overexpressed plants showed a significantly tolerance to cold stress, with higher growth vigour compared to the wild types. The results showed that the Gthu17439 (GthCBF4) could be playing a significant role in enhancing cold stress tolerance in cotton and can be further exploited in developing a more cold stress tolerance cotton germplasm
REVIEW | doi:10.20944/preprints202101.0213.v1
Subject: Biology, Anatomy & Morphology Keywords: crop diversification; C3 xerophtyes; food security; underutilized crops; drought adaptation strategies
Online: 12 January 2021 (10:19:08 CET)
Citron watermelon (Citrullus lanatus var. citroides) is an underexploited and under-researched crop species with potential to contribute to crop diversification in sub-Saharan Africa and beyond. The species is commonly cultivated in the drier parts of Southern Africa, mainly by smallholder farmers who maintain a wide range of landraces. Understanding the molecular and morpho-physiological basis for drought adaptation of Citron watermelon in these dry environments can aid in screening local germplasm, identification of suitable traits for crop improvement and improving food system resilience among smallholder farmers by adding to crop diversification. This paper reviews literature on drought adaptation of C. lanatus spp. (C3 xerophytes), using the systematic review approach. The review discusses; (i) the potential role of citron watermelon in adding to crop diversification, (ii) alternative food uses and potential by-products that can be processed from citron watermelon and (iii) the role of Sub-Saharan farmers as key actors in conserving citron watermelon germplasm and biodiversity. Finally, the review provides a summary of significant findings and identifies critical knowledge gaps for further research.
Mon, 11 January 2021
ARTICLE | doi:10.20944/preprints202101.0204.v1
Subject: Biology, Plant Sciences Keywords: Antioxidant; Anti-inflammatory; Chitosan; Flavonoids; Phenolics; Silybum marianum
Online: 11 January 2021 (15:59:31 CET)
Silybum marianum (L.) Gaertn is a rich source of antioxidants and anti-inflammatory flavonolignans with great potential for use in pharmaceutical and cosmetic products. Its biotechnological production using in vitro culture system has been proposed. Chitosan is a well-known elicitor that strongly affects both secondary metabolites and biomass production by plants. The effect of chitosan on S. marianum cell suspension is not known yet. In the present study, suspension cultures of S marianum were exploited for their in vitro potency to produce bioactive flavonolignans in the presence of chitosan. Established cell suspension culture was maintained on the same hormonal media supplemented with 0.5 mg/L BAP (6-benzylaminopurine) and 1.0 mg/L NAA (α-naphthalene acetic acid) under photoperiod 16/8 h (light/dark) and exposed to various treatments of chitosan (ranging from 0.5 to 50.0 mg/L). The highest biomass production was observed for cell suspension treated with 5.0 mg/L chitosan, resulting in 123.3 g/L fresh weight (FW) and 17.7 g/L dry weight (DW) productions. Chitosan treatment resulted in an overall increase in the accumulation of flavonoids, phenolic compounds and silymarin. High accumulation levels of silybin B, silydianin and silybin A were recorded by HPLC analysis. The corresponding extracts displayed interesting antioxidant and anti-inflammatory capacities. In particular, high ABTS antioxidant activity (741.5 μM Trolox C equivalent antioxidant capacity) was recorded in extracts obtained in presence of 0.5 mg/L of chitosan. On the opposite, highest inhibitions of cyclooxygenase 2 (COX-2, 30.5 %), secretory phospholipase A2 (sPLA2, 33.9 %) and 15-lipoxygenase (15-LOX-2, 31.6 %) enzymes involved in inflammation process were measured in extracts obtained in presence of 5.0 mg/L of chitosan. Taken together, these results highlight the high potential of the chitosan elicitation of the S. marianum cell suspension for enhanced production of antioxidant and anti-inflammatory silymarin-rich extracts.
ARTICLE | doi:10.20944/preprints202101.0192.v1
Subject: Biology, Anatomy & Morphology Keywords: naturally infected; hantavirus detection; urine; rodent; tissue
Online: 11 January 2021 (12:45:21 CET)
The natural hosts regarding Orthohantaviruses are rodents, soricomorphs and bats, and it is well known they may cause serious or even fatal diseases among humans worldwide. The virus is persistent among animals and it is shed via urine, saliva and feces, throughout the entirety of their lives. We aim to identify the effectiveness regarding hantavirus detection from rodent tissue samples and urine originating from naturally infected rodents. Initially, animals were trapped at five distinct locations throughout the Transdanubian region in Hungary. Lung, liver, kidney and urine samples were obtained from 163 perished animals. All organs and urine were tested using nested reverse transcriptase-polymerase chain reaction (nRT-PCR). Furthermore, sera were examined for IgG antibodies against DOBV and PUUV viruses by Western Blot assay. IgG antibodies against hantaviruses and/or nucleic acid were detected in 25 (15.3%) cases. Among Apodemus, Myodes, and Microtus rodent species, DOBV, PUUV, TULV were all clearly identified. The virus nucleic acid was detected most effectively from the kidney (100%), while only 55% of screened lung tissues were positive. Interestingly, only 3 out of 20 rodent urine samples were positive regarding nRT-PCR. Moreover, five rodents were seropositive without detectable virus nucleic acid from any of the tested organs.
ARTICLE | doi:10.20944/preprints202101.0189.v1
Subject: Biology, Anatomy & Morphology Keywords: Portunus trituberculatu; climate change; species distribution model; suitable habitat
Online: 11 January 2021 (12:33:19 CET)
Species have shown their habital variations in responding to climate change, especially during the spring and summer spawning seasons. The species distribution model (SDM) is considered the most favorable tool to study the potential effects of climate change on species distribution. Therefore, we developed the ensemble SDM to predict the changes in species distribution of Portunus trituberculatus among different seasons in 2050 and 2100 under the climate scenarios RCP4.5 and RCP8.5. The results of SDM indicate that the distribution of this species will move northward and have obviouse seasonal variations. Meanwhile, the suitable habitat for the species will be significantly reduced in summer, with loses rates ranging from 45.23% (RCP4.5) to 88.26% (RCP.8.5) by 2100s. Habitat reduction will mainly occur in the East China Sea and southern part of the Yellow Sea, while there will be a small increase in the northern Bohai Sea. These findings will be important to manage the ecosystem and fishery, provide an information forecast of this species in the future, and maintain species diversity if the seawater temperature rises.
ARTICLE | doi:10.20944/preprints202101.0185.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Maize; Prolificacy; Linkage analysis; GWAS; Candidate genes; Ethylene signaling
Online: 11 January 2021 (11:28:54 CET)
For the different harvest targets, the requirement for the prolificacy trait of maize was also different, so prolificacy is of great significance for modern production. Although some QTLs and genes associated with prolificacy in teosinte have been reported, the genetic mechanism of prolificacy in maize has not been fully elucidated. In this study, two RIL populations and GWAS population were used to genetic research of prolificacy trait in maize, with multi-environment. Combine linkage analysis and Genome-wide association study has identified a total of 13 QTLs and 8 significant SNPs. There were two genes related to tissue differentiation in the stable QTL qP9-2, and two significant SNPs corresponding to three genes were in QTL qP5-1 and QTL qP7-1, respectively. Four candidate genes GRMZM2G317262, GRMZM2G317584, GRMZM5G882364 and GRMZM2G141679 were finally screened out by qRT-PCR analysis. Based on the function of candidate genes, ethylene signaling pathway plays an important role in the formation of prolificacy in maize. It has deepened our understanding of the formation mechanism of prolificacy and laid a foundation for breeding new varieties with various prolificacy in maize.
Fri, 8 January 2021
Subject: Biology, Anatomy & Morphology Keywords: Stress; fear; anxiety; aggression; veterinary visit; low-stress handling; counterconditioning; behaviour modification; anxiolytic medication; psychoactive drugs; dogs; cats
Online: 8 January 2021 (14:37:01 CET)
A high proportion of dogs and cats are fearful during veterinary visits, which in some cases may escalate into aggression. Here, we discuss factors that contribute to negative emotions in a veterinary setting and how these can be addressed. The set-up of the waiting area (e.g. spatial dividers; elevated places for cat carriers), tailoring the examination and the treatment to the individual, considerate handling (minimal restraint when possible, avoiding leaning over or cornering animals) and offering high-value food or toys throughout the visit can promote security and, ideally, positive associations. Desensitisation and counterconditioning are highly recommended both to prevent and address existing negative emotions. Some negative experiences such as short-term pain from injections can be minimised by using tactile and cognitive distractions. Preemptive analgesia is recommended for known painful procedures. Recommendations for handling fearful animals to minimise aggressive responses are discussed. However, anxiolytics or sedation should be used whenever there is a risk of traumatising an animal or for safety reasons. Stress-reducing measures can decrease stress and fear in patients and consequently their owners – thus strengthening the relationship with the clients as well as increasing the professional satisfaction of veterinary staff.
ARTICLE | doi:10.20944/preprints202101.0165.v1
Subject: Biology, Anatomy & Morphology Keywords: base temperature; base water potential; predictive weed emergence model; weed germination
Online: 8 January 2021 (14:12:28 CET)
The efficacy of weed management depends on the correct control timing according to the seedling emergence dynamics. Since soil temperature and soil moisture are two main factors that determine weed germination, the hydrothermal time model can be used to predict their emergence. The aim of this study was to estimate the base temperature (Tb) and base water potential (Ψb) for germination of Chenopodium album, Amaranthus retroflexus, Setaria pumila and Panicum capillare collected from fields in continental Croatia and then to compare these values with those of Italian populations embedded in the AlertInf model. Germination tests were performed at seven constant temperatures (ranging from 4 to 27°C) and eight water potentials (0.00 to - 1.00 MPa). Estimated Tb and Ψb were 3.4°C, -1.38 MPa for C. album, 13.9°C, -0.36 MPa for A. retroflexus, 6.6°C, -0.71 MPa for S. pumila and 11.0°C, -0.87 MPa for P. capillare, respectively. According to the criterion of overlap of the 95% confidence intervals, only Tb of C. album, and Ψb of A. retroflexus were similar between Croatian and Italian populations. Further field experiments should be conducted in the Croatian field to monitor weed emergence patterns of C. album and to calibrate the AlerInf equation parameters.
ARTICLE | doi:10.20944/preprints202012.0689.v2
Subject: Biology, Anatomy & Morphology Keywords: Meme; memetic; culture; propagation; equilibrium; inheritance; extinction; resistance; evolution; natural selection; Fermi Paradox
Online: 8 January 2021 (13:37:59 CET)
Background: Conceived as a unit of lasting cultural (mostly vertical) trait transmission, memes now include transient horizontally transmitted fads. Memes may sometimes follow the logic of population genetics, e.g. learned birdsong, but not always over the diverse range found in human hosts. Much current work focuses on selection of memes rather than hosts. Methods: We analyze equilibrium between gene-meme and meme-meme competing propagators and consider whether a meme is linked to reproduction (e.g. vertical culture transmission), or not. We employ a genetic component and combined meme induced fitness components for hosts, while memes have replication factors to distinguish from what’s good for the host (fitness). To anticipate future meme effects on population stability we use a Monte Carlo simulation roughly calibrated to the Industrial Revolution. Results: A basic effective calculus of memetic trait competition and interaction with genes is derived and analyzed. The transient nature of short term memes may be a defense against accumulation of deleterious memes. Horizontally transmitted (panmictic) memes with high spreading rate will often not equalize with a genetic trait, spreading outside of natural selection of the hosts, presenting a cumulative existential threat. Vertical transmission reduces replication rate and allows group selection against deleterious memes. Competing mutually exclusive memes contribute to inequality and altruism, but compete through adverse fitness since exclusivity assumes low conversion. Conclusions: The advantage of a portfolio of groups or species may not accrue to a single group. This analytical understanding elevates meme-risk to the level of a candidate solution to the so-called Fermi Paradox, as interstellar travel might require a planet wide group.
Wed, 6 January 2021
ARTICLE | doi:10.20944/preprints202101.0125.v1
Subject: Biology, Anatomy & Morphology Keywords: COVID-19; coronavirus; green space; planetary health; nature connectedness; public health; nature-based interventions
Online: 6 January 2021 (15:04:09 CET)
The COVID-19 pandemic has brought about unprecedented changes to human lifestyles across the world. The virus and associated social restriction measures have been linked to an increase in mental health conditions. A considerable body of evidence shows that spending time in and engaging with nature can improve human health and wellbeing. Our study explores nature’s role in supporting health during the COVID-19 pandemic. We created web-based questionnaires with validated health instruments and conducted spatial analyses in a geographic information system (GIS). We collected data on people’s patterns of nature exposure, associated health and wellbeing responses, and potential socioecological drivers such as relative deprivation, access to greenspaces, and land-cover greenness. We applied a range of statistical analyses including bootstrap resampled correlations and binomial regression models, adjusting for several potential confounding factors. We found that respondents significantly changed their patterns of visiting nature as a result of the COVID-19 pandemic. People spent more time in nature and visited nature more often during the pandemic. People generally visited nature for a health and wellbeing benefit and felt that nature helped them cope during the pandemic. Greater land-cover greenness within a 250 m radius around a respondent’s postcode was important in predicting higher levels of mental wellbeing. There were significantly more food-growing allotments within 100 m and 250 m of respondents with high mental wellbeing scores. The need for a mutually-advantageous relationship between humans and the wider biotic community has never been more important. We must conserve, restore and design nature-centric environments to maintain resilient societies and planetary health.
REVIEW | doi:10.20944/preprints202101.0110.v1
Subject: Biology, Anatomy & Morphology Keywords: Amphiploidy; Disomic Polyploidy; Plant Genome Evolution; Neo-polyploidy; Polysomic Polyploidy
Online: 6 January 2021 (11:10:40 CET)
Polyploidy is a condition of having more than two sets of chromosomes. Polyploid plants may be artificially obtained through chemical, physical and biological methods (2n gametes). It is considered an interesting approach due to increased genescope and expression, thus resulting in phenotypic changes, such as yield and product quality. Nonetheless, breeding new cultivars through induced polyploidy should overcome deleterious effects partly contributed by genome and epigenome instability after polyploidization. Furthermore, shortening the time required from early chromosome set doubling to the final selection of high yielding superior polyploids is a must. Despite these hurdles, plant breeders have successfully obtained polyploid bred-germplasm in broad range of forages from optimized application methods, concentration and time mainly using colchicine. These experimental polyploids proved to be a valuable tool for understanding gene expression that is driven by dosage dependent gene expression, altered gene regulation and epigenetic changes. Isozymes and DNA-based markers aided on the identification of rare alleles for particular loci when compared with diploids, which may explain their heterozygosity, phenotypic plasticity and adaptability to diverse environments. It has also been observed that experimentally induced polyploid germplasm could enhance fresh herbage yield and quality, e.g. leaf protein content, leaf total soluble solids, water soluble carbohydrates and sucrose content. Offspring of experimentally obtained hybrids underwent selection for several generations to improve their performance and stability.
Tue, 5 January 2021
ARTICLE | doi:10.20944/preprints202101.0102.v1
Subject: Biology, Anatomy & Morphology Keywords: invasive species; Noctuidae; host plants; polyphagous insects; host-strain; pest management
Online: 5 January 2021 (17:12:12 CET)
The alien invasive insect pest Spodoptera frugiperda Smith (Lepidoptera: Noctuidae), commonly referred to as Fall Armyworm (FAW), is a polyphagous insect feeding on more than 350 host plants in addition to maize in its native habitat. Due to the voracious nature of FAW, significant yield losses on maize production were reported across the African continent since its detection in 2016. Despite being a polyphagous insect, little is known about its alternative host plants in the new habitat including Mozambique. This study aimed to assess the host range of FAW in the central province of Manica, Mozambique. A field survey was conducted from May to August 2019 (dry season of 2018/2019 cropping season) and in December 2019 and January 2020 (rainy season of 2019/2020 cropping season) in maize fields and crops often mixed with maize or located in the vicinity of maize fields. A total of 1291 fields were surveyed. In each field, 20 plants were selected in a “W” pattern and checked for the presence of FAW egg masses and/or larvae. At the time of the sampling, no evidence was found suggesting that in Manica province FAW feeds in crops other than maize because out of 35 different crops surveyed, FAW was only recorded on maize. Results from this study suggest that the strain of FAW occurring in Manica province might be the one specialized in maize or the continuous availability of maize fields throughout the year is influencing the choices of the host plants of this invasive insect pest.
REVIEW | doi:10.20944/preprints202101.0099.v1
Subject: Biology, Anatomy & Morphology Keywords: biomedical model; hearing impairment; regeneration; stem cells; zebrafish
Online: 5 January 2021 (14:23:23 CET)
Zebrafish is an excellent model for observing human genetic disorders. Hearing impairment is the most common genetic disorder including syndromic & non-syndromic hearing loss. Stem cell therapies are considered a new hope in case of hearing impairment. Stem cells are the master cells of the human body and having the capability to differentiate into any other form of cells in more than 200 types of cells (regeneration). This review article describes zebrafish as a biomedical model for stem cell research in hearing impairment, which revolutionized the biomedical arena to compete for the challenges.
ARTICLE | doi:10.20944/preprints202101.0094.v1
Subject: Biology, Anatomy & Morphology Keywords: Beauveria bassiana; Biological control; Entomopathogenic fungi; Spodoptera frugiperda; Zea mays
Online: 5 January 2021 (13:48:53 CET)
Spodoptera frugiperda is a widely distributed insect pest that causes major economic losses in various crops, particularly maize. On the other hand, Beauveria bassiana is an entomopathogenic fungus that establishes symbiotic associations with many plants and contributes to tolerance against biotic and abiotic stresses. In the present work, under field conditions, 1x106 (first trial) and 1x10⁸ (second trial) of B. bassiana (GHA strain) blastospores were used for corn’s seed inoculation. In the first field trial, a higher number of larvae were present in the negative control plants in comparison with those in B. bassiana-treated plants. No larvae were found in negative control and B. bassiana-treated plants in the second field trial. In further laboratory experiments, the effects of the B. bassiana strains GHA, in addition to a native strain (PTG4) also delivered via seed treatment in maize seedlings, on S. frugiperda growth, development, and mortality were evaluated. 1x10⁶ B. bassiana blastospores were used to inoculate maize seeds, which were germinated and grown to seedlings under growth chamber conditions. Third-instar S. frugiperda larvae were allowed to feed on B. bassiana-treated and -untreated (negative control) seedlings until reaching 6th instar and transferred to artificial diet until reaching adult stage. Results showed that larvae feeding on B. bassiana strain PTG4 prolonged their larval stage. Furthermore, feeding with plants treated with B. bassiana strains yielded fewer S. frugiperda male moths and the female moths emerged with altered wings, compared with the untreated control. In conclusion, seed treatment with B. bassiana in maize reduced S. frugiperda infestation of maize plants in field trials. Besides S. frugiperda development was affected in laboratory trials.
Subject: Biology, Animal Sciences & Zoology Keywords: Stress; fear; anxiety; aggression; veterinary visit; low-stress handling; counterconditioning; behaviour modification; anxiolytic medication; psychoactive drugs; dogs; cats
Online: 5 January 2021 (11:15:02 CET)
A high proportion of dogs and cats are fearful during veterinary visits, which in some cases may escalate into aggression. Here, we discuss factors that contribute to negative emotions in a veterinary setting and how these can be addressed. We briefly summarise the available evidence for the interventions discussed. The set-up of the waiting area (e.g. spatial dividers; elevated places for cat carriers), tailoring the examination and the treatment to the individual, considerate handling (minimal restraint when possible, avoiding leaning over or cornering animals) and offering high-value food or toys throughout the visit can promote security and, ideally, positive associations. Desensitisation and counterconditioning are highly recommended both to prevent and address existing negative emotions. Short-term pain from injections can be minimised by using tactile and cognitive distractions and topical analgesics, which are also indicated for painful procedures such as ear cleanings. Recommendations for handling fearful animals to minimise aggressive responses are discussed. However, anxiolytics or sedation should be used whenever there is a risk of traumatising an animal or for safety reasons. Stress-reducing measures can decrease fear and stress in patients and consequently their owners, thus strengthening the relationship with the clients as well as increasing the professional satisfaction of veterinary staff.
BRIEF REPORT | doi:10.20944/preprints202012.0145.v2
Subject: Biology, Anatomy & Morphology Keywords: Theraphosidae; muscle cramps; convulsion; spider; envenomation; bite
Online: 5 January 2021 (10:34:40 CET)
Despite the popularity of theraphosids, detailed reports on bite symptoms are still limited to few geographic regions and subfamilies. We therefore examined 363 published bite reports and noticed muscles cramps caused by theraphosids from nearly all continents and subfamilies. Symptoms are mostly locally restricted and mild, but 12.7% of victims experience pronounced cramps with highest incidence rates by Poecilotheriinae, Harpactirinae and Stromatopelminae subfamilies. We discuss how variations in venom quantity correlate with muscle cramp prevalence.
Mon, 4 January 2021
ARTICLE | doi:10.20944/preprints202101.0060.v1
Subject: Biology, Plant Sciences Keywords: Korean soybean varieties; nsSNP; Biomarker; SIFT; Polyphen; PANTHER; I-mutant 2.0
Online: 4 January 2021 (16:25:22 CET)
Soybean is a highly nutritious legume grown globally as a food and feed crop. An examination of a collection of 10 cultivated and 6 wild Korean soybean varieties showed that there is phenotypic variability notable in different soybeans. Therefore, to develop a list of biomarker candidates useful for growing soybeans of better quality and quantity, the genes of 16 Korean soybean varieties were compared with those of the reference Glycine max var. Williams 82. The comparison was made through gene sequencing to facilitate selection of nsSNPs. The objective of the study was to find out the structural and functional variations caused by nsSNPs and discuss whether the collection of Korean soybean varieties qualifies as biomarkers based on their phenotypic traits. Analysis of the data collected was done using four software: SIFT, Polyphen, PANTHER, and I-mutant 2.0, which are designed to detect the rate of functional and structural variations caused by the nsSNPs in cultivated and wild soybean varieties. Genotypic information obtained in the analysis was used to develop a core collection of biomarkers based on whether nsSNP content was found in more than half of the 16 samples. Therefore, the list of biomarker candidates developed from this study showed that Korean soybean could provide valuable information needed in both future crop genetic research and identification of biomarkers.
REVIEW | doi:10.20944/preprints202101.0057.v1
Subject: Biology, Anatomy & Morphology Keywords: Genetic coding; free energy transduction; non-equilibrium thermodynamics; transition-state stabilization; conformational change; aminoacyl-tRNA synthetases; emergent phenomena
Online: 4 January 2021 (16:21:16 CET)
Bioenergetics, genetic coding, and catalysis are all difficult to imagine emerging without pre-existing historical context. That context is often posed as a “Chicken and Egg” problem; its resolution is concisely described by de Grasse Tyson: “the egg was laid by a bird that was not a chicken”. The concision and generality of that answer furnish no details—only an appropriate framework from which to examine detailed paradigms that might illuminate paradoxes underlying these three life-defining biomolecular processes. We examine experimental aspects here of five examples that all conform to the same paradigm. The paradox in each example is resolved by coupling if, and only if, conditions for two related transitions between levels. One drives, and each restricts fluxes through, or “gates” the other. That reciprocally-coupled gating, in which two gated processes constrain one another, maps onto the formal structure of “strange loops”. That mapping may help unite the axiomatic foundations of genetics, bioenergetics, and catalysis. As a physical analog for Gödel’s logic, biomolecular strange-loops provide a natural metaphor around which to organize these data, linking biology to the physics of information, free energy, and the second law of thermodynamics.
ARTICLE | doi:10.20944/preprints202101.0050.v1
Subject: Biology, Anatomy & Morphology Keywords: antibiotics residue; antimicrobial resistance; ethno-veterinary practices; Herbal formulations; cattle health; dairy farmers; cost effective health care model
Online: 4 January 2021 (13:56:26 CET)
This study demonstrated that antibiotic residue in milk can be reduced when dairy farmers use Ethno-veterinary Practices (EVP) based on herbal alternatives to prevent and cure common clinical conditions in cattle instead of antibiotics. Of the 220 farmers selected for the study, 140 were trained and motivated to use validated herbal formulations, 80 were kept as control. Milk samples from the selected farmers (except Thirukanurpatti milk society) tested positive for antibiotic residue in the baseline survey. One year after interventions, the milk from 123 (87.86%) farmers out of 140, were without any detectable antibiotic residue, while samples from 11 farmers (7.85%) were low positive for either Beta-lactams or sulphonamides and 6 (4.29%) were positive for Beta lactams and/or sulphonamides. These 17 (11 + 6) farmers had used antibiotics along with herbal formulations. The milk samples from the control groups were positive for beta lactam and sulphonamide. There was suggestive significance of change in knowledge, attitude and practice of EVP among the farmers from Kerala and Tamil Nadu. A progressive reduction in the incidence of mastitis, enteritis, repeat breeding and cowpox were observed from 2016 to 2019 among the cows treated with EVP. Use of herbal alternative also resulted in a significant reduction in health care expenditure of cattle.
ARTICLE | doi:10.20944/preprints202101.0047.v1
Subject: Biology, Anatomy & Morphology Keywords: Stool; Fecal; Microbiome; Microbiota; Heterogeneous; Homogeneous; Sample
Online: 4 January 2021 (13:29:00 CET)
Background. Inferior quality of biological material compromises data, slows discovery, and wastes research funds. The gut microbiome plays a critical role in human health and disease, yet little attention has been given to optimizing collection and processing methods of human stool. Methods. We collected the entire bowel movement from 2 healthy volunteers: one to examine stool sample heterogeneity and one to test stool sample handling parameters. Sequencing and bi-oinformatic analyses were used to examine the microbiome composition. Results. The microbiome profile varied depending on where the subsample was obtained from the stool. The exterior cortex of the stool was rich in specific phyla and deficient in others while the interior core of the stool revealed opposite microbiome profiles. Sample processing also re-sulted in varying microbiome profiles. Homogenization and stabilization at 4°C gave superior microbial diversity profiles compared to the fresh or frozen subsamples of the same stool sample. Bacterial proliferation continued in the fresh subsample when processed at ambient temperature. Bacteroidetes proliferated and Firmicutes diminished during the 30-minute processing of fresh sample. The frozen sample had good overall diversity but Proteobacteria diminished likely be-cause of the freeze/thaw. Conclusions. The microbiome profile is specific to the section of the stool being sampled. Stool sample collection, homogenization, and stabilization at 4°C for 24 hours provides a “neat”, high-quality sample of sufficient quantity that can be banked into aliquots with nearly identical microbial diversity profiles. This collection pipeline is essential to accelerate our understanding of the gut microbiome in health and disease.
TECHNICAL NOTE | doi:10.20944/preprints202101.0034.v1
Subject: Biology, Plant Sciences Keywords: clearing; 3D imaging; Arabidopsis thaliana; embryo; confocal microscopy; cell wall staining; fluorescent reporter; GFP
Online: 4 January 2021 (12:34:36 CET)
Tissue clearing methods combined with confocal microscopy have been widely used for studying developmental biology. In plants, ClearSee is a reliable clearing method that is applicable to a wide range of tissues and is suitable for gene expression analysis using fluorescent reporters, but its application to the Arabidopsis thaliana embryo, a model system to study morphogenesis and pattern formation, has not been described in the original literature. Here we describe a ClearSee-based clearing protocol, which is suitable for obtaining 3D images of Arabidopsis thaliana embryos. The method consists of embryo dissection, fixation, washing, clearing, and cell wall staining, and enables high quality 3D imaging of embryo morphology and expression of a fluorescent reporter with the cellular resolution.
ARTICLE | doi:10.20944/preprints202101.0032.v1
Subject: Biology, Anatomy & Morphology Keywords: Erasmoneura vulnerata; augmentative biological control; invasive pests; grapevine; Chrysoperla carnea; Orius majusculus; generalist predators
Online: 4 January 2021 (12:29:56 CET)
Outbreaks of the Nearctic leafhopper Erasmoneura vulnerata represent a recent issue for winegrowers in Southern Europe, in particular in North-eastern Italy. Problems are frequent in organic vineyards because insecticides labeled for organic viticulture show limited effectiveness towards leafhoppers. On the other hand, the response by naturally occurring predators and parasitoids to E. vulnerata populations in vineyards is often unable to keep leafhopper densities under levels that are acceptable for winegrowers. Here we evaluated the potential of two generalist predators, i.e., Chrysoperla carnea and Orius majusculus, in controlling E. vulnerata populations. Laboratory and semi-field experiments were carried out to evaluate both species' predation capacity on E. vulnerata nymphs. Then, predators were released in vineyards colonized by large E. vulnerata populations. Both predator species exhibited a remarkable voracity in the laboratory and significantly reduced leafhopper densities in semi-field experiments. Predator releases in vineyards reduced leafhopper densities by about 30%. Results obtained in laboratory, semi-field, and field experiments are discussed to implement these biocontrol agents' use in pest control tactics.
ARTICLE | doi:10.20944/preprints202101.0012.v1
Subject: Biology, Anatomy & Morphology Keywords: urban forestry; work analysis; residual biomass; pruning costs
Online: 4 January 2021 (11:24:12 CET)
The Italian Stone Pine (Pinus pinea L.) is one of the most employed ornamental trees in towns with Mediterranean climates. For example, in the city of Rome, Pinus is the most common genus, with more than 51,000 trees. This study investigates technical and economic features of maintenance operations of Stone Pines and evaluates the productivity and costs of the observed yards. Pruning and felling are the most frequent management operations of trees in towns and this study analyzes the features of these operations carried out in 14 work sites. The operations were carried out either with aerial platforms (19 trees) or ascending the crown by tree-climbing (6 trees). The operations were sampled with time studies (12 trees for pruning and 13 for felling). Work time was measured from the beginning of operations to the transport of the residual biomass to the collection and loading point, using centesimal stopwatches and video recording. The total residual biomass was weighed or assessed. Total observation time amounted to 63.1 hours. The evaluation of the costs of each work site considered the fixed and the variable costs and the costs for the labor force. A Multiple Linear Regression model (statistics: determination coefficient R2: 0.74, adjusted R2: 0.67, p-value < 0.001) which utilizes four regressors easily evaluable before the work, was adopted to predict the gross time of the operations. This paper can contribute to optimize trees maintenance methods in urban sites and to assess the potential residual wood biomass attainable from urban forestry maintenance in the city of Rome.
Thu, 31 December 2020
ARTICLE | doi:10.20944/preprints202012.0826.v1
Subject: Biology, Anatomy & Morphology Keywords: Amegilla calens; Gossypium hirsutum; Meskine; pollination efficiency; yields
Online: 31 December 2020 (16:29:01 CET)
This study was carried out to evaluate the impact of Amegilla calens bee on fruit and seed yields of G. hirsutum in an experimental field, in September 2018 and 2019. The experiments were carried out on 540 flowers divided in four treatments: 120 flowers accessible to all visitors; 120 flowers bagged to avoid all visits; 200 flowers protected and uncovered when they were opened, to allow A. calens visits; 100 flowers bagged then uncovered and rebagged without the visit of insects or any other organism. Bee’s daily rhythm of activity, its foraging behaviour on flowers, its pollination efficiency, the fruiting rate, the number of seeds per fruit and the percentage of normal seeds were evaluated. Among the 20 insect species recorded on G. hirsutum flowers, A. calens was the most frequent insect with 30.72 % of 655 visits. On flowers, individual bee intensely collected pollen and slightly harvested nectar. The mean duration of a visit per flower was 23.56 sec for pollen harvest and 13.68 sec for nectar collection. For the two years, through its pollination efficiency, A. calens increased the fruiting rate by 20.30 %, as well as the percentage of normal seeds by 32.39 %.
ARTICLE | doi:10.20944/preprints202012.0814.v1
Subject: Biology, Anatomy & Morphology Keywords: biosystems; order-stability; classical versus quantum entropy; open quantum systems; quantum channel; entanglement
Online: 31 December 2020 (13:39:08 CET)
This paper is our attempt on the basis of physical theory to bring more clarification on the question ``What is life?'' formulated in the well-known book of Schr\"odinger in 1944. According to Schr\"odinger, the main distinguishing feature of biosystem's functioning is the ability to preserve its order structure or, in the mathematical terms, to prevent increasing of entropy. Since any biosystem is fundamentally open, it is natural to use open system's theory. However, Schr\"odinger's analysis shows that the classical theory is not able to adequately describe the order-stability in a biosystem. Schr\"odinger should also appeal to the ambiguous notion of negative entropy. We suggest to apply the quantum theory. As is well-known, behaviour of the quantum von Neumann entropy crucially differs from behaviour of the classical entropy. We consider a complex biosystem $S$ composed of many subsystems, say proteins, or cells, or neural networks in the brain, i.e., $S=(S_i).$ We study the following problem: if the composed system $S$ can preserve the ``global order'' in the situation of increase of local disorder and if $S$ can preserve its entropy while some of $S_i$ increase their entropies We show that within quantum information theory the answer is positive. The significant role plays entanglement of the subsystems states. In the absence of entanglement, increasing of local disorder generates disorder increasing in the compound system $S$ (as in the classical regime).
ARTICLE | doi:10.20944/preprints202012.0793.v1
Subject: Biology, Anatomy & Morphology Keywords: Erasmoneura vulnerata; Vitis vinifera; insecticides; vineyard management
Online: 31 December 2020 (12:15:14 CET)
The American leafhopper Erasmoneura vulnerata, detected in Europe in early 2000s, has recently become a pest in North-Italian vineyards. Issues were recorded in organic and conventional vine-yards despite the application of insecticides devoted to the control of other pests. Erasmoneura vulnerata completes three generations, and the second generation is frequently associated to large populations. The selection of appropriate active ingredients and the timing of their application is crucial for effective pest control. Field trials were carried out in North-eastern Italy, using a randomized design, to evaluate the impact of insecticides applied against other grapevine leafhoppers on E. vulnerata populations. The beginning of the second generation was selected as best timing for insecticide application. For a number of natural products, two applications were planned. Among the selected insecticides, the most effective were acetamiprid, flupyradifurone and lamb-da-cyhalothrin. Regarding natural products, the most effective was kaolin that could represent an alternative to pyrethrins in organic vineyards. The identification of pest threshold levels and the evaluation of side effects of the most effective insecticides on key natural enemies occurring in vineyards are required
ARTICLE | doi:10.20944/preprints202012.0791.v1
Subject: Biology, Anatomy & Morphology Keywords: Mint; Plant volatiles; Electronic Nose; Principal Component Analysis; Linear Discriminant Analysis; k-Nearest-Neighbors Analysis
Online: 31 December 2020 (11:45:40 CET)
Mints emit diverse scents that exert specific biological functions and are relevance for applications. The current work strives to develop electronic noses that can electronically discriminate the scents emitted by different species of Mint as alternative to conventional profiling by gas chromatography. Here, 12 different sensing materials including 4 different metal oxide nanoparticle dispersions (AZO, ZnO, SnO2, ITO), one Metal-Organic Frame as Cu(BPDC), and 7 different polymer films including PVA, PEDOT: PSS, PFO, SB, SW, SG, PB were used for functionalizing of QCM sensors. The purpose was to discriminate six economically relevant Mint species (Mentha x piperita, Mentha spicata, Mentha spicata ssp. crispa, Mentha longifolia, Agastache rugosa, and Nepeta cataria). The adsorption and desorption datasets obtained from each modified QCM sensor were processed by three different classification models including Principal Component Analy-sis (PCA), Linear Discriminant Analysis (LDA), and k-Nearest Neighbor Analysis (k-NN). This allowed discriminating the different Mints with classification accuracies of 97.2% (PCA), 100% (LDA), and 99.9% (k-NN), respectively. Prediction accuracies with a repeating test measurement reached up to 90.6% for LDA, and 85.6% for k-NN. These data demonstrate that this electronic nose can discriminate different Mint scents in a reliable and efficient manner.
ARTICLE | doi:10.20944/preprints202012.0773.v1
Subject: Biology, Anatomy & Morphology Keywords: secondary data analysis; PARP/PARG; transcriptomics; biotrophy-necrotrophy transition
Online: 31 December 2020 (09:10:15 CET)
We identified key genes needed for maintenance and growth and homed in on genes where there could be a competition between maintenance requirements (stress) and growth requirements. Such processes are synthesis of arginine, synthesis of DNA-bases, nitric oxide synthesis needing arginine, autophagy, DNA synthesis and DNA repair. Using procedures previously developed for the use of sets of downloaded transcriptomic data to test hypotheses concerning at what time under the course of infection of plants genes are expressed for the two pathogens Fusarium graminearum and Magnaporthe oryzae, we constructed a simplified regulatory network for these genes for both organisms. Our analysis shows that the transcription effort (cost) to maintain the fungal cells (maintenance) are high before infection and in early infection. During the following biotrophic phase maintenance cost drops for later in the transition to the necrotrophic phase increase dramatically. Finally, in the necrotrophic phase, maintenance is lower again despite the high growth rate that can also cause stress. The expressions of all identified genes behaved almost similar for both fungi except the DNA repair genes PARP/PARG that was not responding or absent in the mainly clonal M. oryzae which might indicate this species is more subject to evolution by point mutations than F. graminearum where sexual reproduction is frequent. The potential consequences of these different roles for PARP/PARG in the development and the accelerated breakage of host species resistance in a Red Queen dynamics scenario is discussed. Our analysis demonstrates the possibility to use large transcriptome datasets and co-regulations between key genes to test hypotheses and discusses the advantages with this technique as complement to molecular techniques employing knockouts and over-expression of target genes to suggest gene roles.
ARTICLE | doi:10.20944/preprints202012.0769.v1
Subject: Biology, Anatomy & Morphology Keywords: biochar; compost; vermicompost; biochar-compost mixtures; soil fertility; Swiss chard; nitrate content; leaf pigment content
Online: 31 December 2020 (07:32:17 CET)
In recent years, soil addition with organic amendments, such as biochar and compost, has gained attention as an effective agronomic practice to sustain soil fertility, enhance plant growth and crop yield. Well known are the positive effects of compost on yield of a wide crop varieties, while both positive and negative responses are reported for biochar Therefore, the aim of the study was to verify the effect of biochar mixed with three types of compost on quanti-qualitative response of Swiss chard (Beta vulgaris L. cycla), a leafy green vegetable rich in dietary antioxidants, largely consumed worldwide. A factorial experiment in pots with two factors, including biochar (without biochar and with biochar from vine pruning residues) and compost (without compost, with compost from olive pomace, with vermicompost from cattle manure and with compost from cattle anaerobic digestate), was setup. Two growth cycles were considered and a set of quantitative (height of plants, number, area and fresh weight of leaves) and qualitative parameters (carotenoid, chlorophyll, total N and NO3-content of leaves) were analyzed. Biochar decreased plant growth and NO3- leaf content; on the contrary, it increased total N leaf content, while compost improved all the considered parameters. The interactive effect of biochar and compost was evident only on total N and NO3- leaf content. In our experimental conditions, the compost showed to be the best option to improve Swiss chard growth and increase the phytopigments content, while the biochar-compost mixtures didn’t produce the expected effect.
Wed, 30 December 2020
REVIEW | doi:10.20944/preprints202012.0766.v1
Subject: Biology, Anatomy & Morphology Keywords: Cannabis; marijuana; marihuana; tissue culture; review; regeneration; floral reversion; micropropagation; TDZ; DKW
Online: 30 December 2020 (17:24:27 CET)
The recent legalization of Cannabis sativa L. in many regions has revealed a need for effective propagation and biotechnologies for the species. Micropropagation affords researchers and producers methods to rapidly propagate insect/disease/virus free clonal plants, store germplasm, and forms the basis for other biotechnologies. Despite this need, research in the area is limited due to the long history or prohibitions and restrictions. Existing literature has multiple limitation: many publications use hemp as a proxy for drug-type Cannabis when it is well established that there is significant genotype specificity, studies using drug-type cultivars are predominantly op-timized using a single cultivar, most protocols have not been replicated by independent groups, and some attempts demonstrate a lack of reproducibility across genotypes. Due to culture decline and other problems the multiplication phase of micropropagation (stage 2) has not been fully developed in many reports. This review will provide a brief background on the history and botany of Cannabis as well as a comprehensive and critical summary of Cannabis tissue culture. Special attention will be paid to current challenges faced by researchers, the limitations of existing Cannabis micropropagation studies, and recent developments and future directions of Cannabis tissue culture technologies.
Subject: Biology, Anatomy & Morphology Keywords: Leaf monoterpene emission; heath stress; chlorophyll fluorescence; photosynthesis; grapevine
Online: 30 December 2020 (16:51:05 CET)
Rising temperature is among the most remarkably stressful phenomena induced by global climate changes with negative impacts on crop productivity and quality. It has been previously shown that volatiles belonging to the isoprenoid family can confer protection against abiotic stresses. In this work, two Vitis vinifera cv. ‘Chardonnay’ clones (SMA130 and INRA809) differing for a mutation of the DXS gene encoding for 1-deoxy-D-xylulose-5-phosphate (the first dedicated enzyme of the 2C-methyl-D-erythritol-4-phosphate (MEP) pathway) and involved in the regulation of isoprenoids biosynthesis were investigated in field trials and laboratory experiments. Leaf monoterpene emission, chlorophyll fluorescence and gas-exchange measurements were assessed over three seasons at different phenological stages and either carried out in vivo or controlled conditions under contrasting temperatures. A significant (p<0.001) increase in leaf monoterpene emission was observed in INRA809 when plants were experiencing high temperatures and over two experiments while no differences were recorded for SMA130. Significant variation was observed for the rate of leaf CO2 assimilation under heat stress, with INRA809 maintaining higher photosynthetic rates and stomatal conductance values than SMA130 (p=0.003) when leaf temperature increased above 30°C. At the same time, maximum photochemical quantum yield of PSII (Fv/Fm) was affected by heat stress in the non-emitting clone (SMA130), while the INRA809 showed a significant resilience of PSII under elevated temperature conditions. Consistent data were recorded between field seasons and temperature treatments in controlled environment conditions suggesting a strong influence of monoterpene emission on heat tolerance under elevated temperatures. This work provides further insights on the photoprotective role of isoprenoids under high temperatures in Vitis vinifera and additional studies should focus at unravelling the mechanisms underlying heat tolerance on the monoterpene-emitter grapevine clone.
REVIEW | doi:10.20944/preprints202012.0757.v1
Subject: Biology, Anatomy & Morphology Keywords: Ocean front; Marine ecology; Fisheries; Front detection; Satellite imagery; Feature-based approach
Online: 30 December 2020 (14:53:37 CET)
This paper provides a concise review of remote sensing of ocean fronts and its applications in marine ecology and fisheries, with a particular focus on the most popular front detection algorithms/techniques: Canny (1986), Cayula and Cornillon (1990, 1992, 1995), Miller (2004, 2009), Shimada et al. (2005), Belkin and O’Reilly (2009), and Nieto et al. (2012). A case is made for feature-based approach in marine ecology and fisheries that emphasizes fronts as major structural and circulation features of the ocean realm that play key roles in various aspects of marine ecology.
Tue, 29 December 2020
CONCEPT PAPER | doi:10.20944/preprints202012.0736.v1
Online: 29 December 2020 (15:48:00 CET)
Cannabis is one of the oldest cultivated crops in the history for food, fiber and drugs for thousands of years. Extension of cannabis genetic variation developed in a wide- ranging choice of varieties with various complementary phenotypes and secondary metabolites. Cannabis grow practices is very diverse, especially indoor cultivation factors, such as different lighting conditions, pot size, humidity, fertilizers. These growth factors influence a lot on the production of cannabinoids. For medical or pharmaceutical purposes, ratio of CBD or THC is very important. Plants traits and metabolic compounds are related to various conditions produced by microbes. Investigating this crosstalk between plants and microbes can play a vital role not only for stimulating the biosynthetic and signaling pathways of the host plants for the production of agronomically or pharmaceutically essential metabolic compounds but also against pathogens. This study emphasis on decoding the crosstalk between cannabis and associated microbes in the belowground environmental niches that would unravel the complexity of stabilizing cannabinoid production.
Mon, 28 December 2020
Online: 28 December 2020 (16:59:04 CET)
Celiac disease (CD) is a permanent intolerance to dietary protein, gluten, from wheat rye and barley. It occurs in about 1% worldwide population, in genetically predisposed individuals bearing human leukocyte antigen (HLA) DQ2/DQ8. Gut epithelial cell stress and innate immune activation are responsible for breaking oral tolerance to gliadin, the gluten component. To date, the only treatment available for CD is a long-term gluten-free diet. Several evidences show that an altered composition of the intestinal microbiota (dysbiosis) could play a key role in the pathogenesis of CD, through the modulation of intestinal permeability and the regulation of the immune system. Here we show that gliadin induces a chronic ER stress condition in the small intestine of a CD mouse model and that the co-administration of probiotics efficiently attenuates both UPR and gut inflammation. Moreover, the composition of probiotics formulations might differ in their activity at molecular level, especially toward the three axes of the UPR. Therefore, rebalancing the gut microbiota composition by probiotics administration might rep-resent a new strategy to treat CD affected patients.
REVIEW | doi:10.20944/preprints202012.0708.v1
Subject: Biology, Anatomy & Morphology Keywords: Phytochemicals; SARS-CoV-2; S-Protein; Molecular docking; ACE 2
Online: 28 December 2020 (16:51:12 CET)
Since December 2019, the worldwide spread of COVID-19 has brought the majority of the world to a standstill, affecting daily lives as well as economy. Under these conditions, it is imperative to develop a cure as soon as possible. On account of some of the adverse side effects of the existing conventional drugs, researchers all around the world are screening natural antiviral phytochemicals as potential therapeutic agents against COVID-19. This paper aims to review interactions of some specific phytochemicals with the receptor binding domain (RBD) of the Spike glycoprotein of SARS-CoV-2 and suggest their possible therapeutic applications. Literature search was done based on the wide array of in-silico studies conducted using broad spectrum phytochemicals against SARS-CoV-2 and other viruses. We shortlisted 26 such phytochemicals specifically targeting the S protein and its interactions with host receptors. To validate the previously published results, we also conducted molecular docking using the AutoDockVina application and identified 6 high potential phytochemicals for therapeutic use based on their binding energies. Besides this, availability of these compounds, their mode of action, toxicity data and cost-effectiveness were also taken into consideration. Our review specifically identifies 6 phytochemicals that can be used as potential treatments for COVID-19 based on their availability, toxicology results and low costs of production. However, all these compounds need to be further validated by wet lab experiments and should be approved for clinical use only after appropriate trials.
ARTICLE | doi:10.20944/preprints202012.0702.v1
Subject: Biology, Anatomy & Morphology Keywords: Sulfur; Hydrogen cyanide; Gas production; Ammonia nitrogen; Propionic acid
Online: 28 December 2020 (13:09:24 CET)
The study aimed to elucidate the optimum level of elemental sulfur, fresh cassava root (FCR), and urea and their effect on gas production, ruminal fermentation, thiocyanate concentration, and in vitro degradability. A 3×2×4 in a completely randomized design were conducted. Factor A was level of sulfur at 0%, 1%, and 2% of concentrate dry matter (DM), factor B was level of urea at 2% and 4% of concentrate DM, and factor C was level of the FCR at 0, 200, 300, and 400 mg of the total substrate. The study found that elemental sulfur, urea, and FCR had no interaction effect on the kinetics of gas, ruminal fermentation, hydrogen cyanide (HCN), and in vitro degradability. Elemental sulfur supplementation (P<0.05) significantly increased the gas produced from an insoluble fraction (b), in vitro DM degradability and either neutral detergent fiber or acid detergent fiber degradability, and propionate (C3) concentration while decreased the ruminal HCN concentration. Urea levels showed a (P<0.05) significant increase of the potential extent of gas production, ruminal NH3-N, and total volatile fatty acid (VFA). FCR supplementation (P<0.05) significantly increased the gas produced from an immediate soluble fraction (a), gas produced from insoluble fraction, gas production rate constant, total VFA, C3 concentration, and HCN while decreased ruminal pH, acetate, and butyrate concentration. It could be concluded that 2% elemental sulfur, 4% urea, and 300 mg FCR showed a greater effect on gas production, ruminal fermentation, and HCN reduction.
COMMUNICATION | doi:10.20944/preprints202012.0699.v1
Subject: Biology, Anatomy & Morphology Keywords: Unmanned Aerial Vehicles; trail mapping; conservation; forestry; canopy cover
Online: 28 December 2020 (12:32:22 CET)
Trail detection in mixed canopy ecosystems has important implications for forest management, monitoring, and conservation, although active sensor technology for sub-canopy trail detection is still developing. In order to assess the effectiveness of UAV(Unmanned Aerial Vehicle)-borne lidar (light detection and ranging) data for small trails (< 2.5m width) in mixed forest canopy cover, we collected lidar data and trail characteristics (canopy cover and trail width) and created a high definition surface model map from the resulting lidar data, and also a high-resolution satellite imagery map using Google Earth. Through participatory mapping methods, seven respondents with limited prior geospatial experience completed a rapid identification of trails on both maps. Respondents’ trails were georeferenced in order to compare the rate of detectability between maps. We found greater detection on the lidar-derived map compared to the Google Earth map. Detectability in Google Earth maps was positively correlated with wider trails and trials with lower canopy. In lidar maps, trail detectability increased with wider trails, but canopy cover had no effect on detection rates. Our data indicate that a mixed-method approach that combines UAV-mounted lidar with high-resolution satellite imagery and participatory mapping increases rapid detection rates of small trails under varying canopy cover and trail widths.
ARTICLE | doi:10.20944/preprints202012.0691.v1
Subject: Biology, Anatomy & Morphology Keywords: conservation; gene pool; geographical distribution; threatened; valorization
Online: 28 December 2020 (11:54:56 CET)
The study presents an updated overview of the 14 non-endemic threatened Crop Wild Relatives (CWR) in Italy: Aegilops biuncialis, Ae. uniaristata, Ae. ventricosa, Asparagus pastorianus, Beta macrocarpa, Brassica insularis, B. montana, Crambe hispanica subsp. hispanica, C. tataria subsp. tataria, Ipomoea sagittata, Lathyrus amphicarpos, L. palustris, Vicia cusnae and V. serinica. Geographical distribution, ecology (with plant communities and habitat 92/43/EEC aspects), genetics (focused on gene pools), property, and in situ and ex situ conservation were analyzed. In addition, with the aim of their protection and valorization, specific actions are recommended.
ARTICLE | doi:10.20944/preprints202012.0690.v1
Subject: Biology, Anatomy & Morphology Keywords: Azadirachta indica; Boswellia dalzielii; Metarhizium anisopliae; Vigna unguiculata; efficacy; yield
Online: 28 December 2020 (11:44:30 CET)
Cowpea yield improvement is done by adding agricultural inputs. The use of natural substances as pesticides is being encouraged to fight against cowpea field pests. The pesticidal potentials of aqueous extracts of Azadirachta indica and Boswellia dalzielii, Metarhizium anisopliae, alone and in combination with plant extracts, as well as the commercial insecticide Decis were tested on two Vigna unguiculata varieties in field in two agroecological zones (Guinean Savanah and Sahelian Savanah) of Cameroon. The field trials were arranged in a completely randomized block design with nine treatments including control. Each treatment was replicated four times. Vigna unguiculata plants were sprayed at flowering stage thrice with insecticidal products at 5 days interval. Data assessment consisted of counting ramifications per plant, the number of pods per block, and seed yield. All the tested insecticides significantly (p<0.0001) improved the cowpea yield in the two agro-ecological zones. The productions parameters were highly influenced by variety and agroecological zone. The extracts and their combinations were as effective as synthetic pesticide (Decis). Bafia variety recorded the highest ramification rate (37.03±1.59) when treated with the combination of M. anisopliae and A. indica in Maroua (Sahelian Savanah). The same variety also produced most important pods number (90.50±16.66) in Ngaoundere (Guinean Savanah) with the combination of A. indica and B. dalzielii. The highest seed yield (44.23±2.31) was recorded in Ngaoundere with B125 variety treated with the combination of the three treatments (A. indica, B. dalzielii, M. anisopliae). A. indica, B. dalzielii, M. anisopliae and their combinations could be considered as potential natural input in the improvement of V. Unguiculata yield. This would not only increase V. unguiculata yield but also preserves environment from the pollution due to the use of synthetic residual chemicals.
Subject: Biology, Anatomy & Morphology Keywords: Meme; memetic; culture; propagation; equilibrium; inheritance; extinction; resistance; evolution; natural selection
Online: 28 December 2020 (11:30:49 CET)
Background: Conceived as a unit of lasting cultural (mostly vertical) trait transmission, memes now include transient horizontally transmitted fads. Memes may sometimes follow the logic of population genetics, e.g. learned birdsong, but not always over the diverse range found in human hosts. Much current work focuses on selection of memes rather than their hosts. Methods: We analyze equilibrium between gene-meme and meme-meme competing propagators and consider whether a meme is linked to reproduction (e.g. vertical culture transmission), or not. We employ a genetic component and combined meme induced fitness components for hosts, while memes have replication factors to distinguish from whats good for the host (fitness). To anticipate future meme effects on population stability we use a Monte Carlo simulation roughly calibrated to the Industrial Revolution. Results: A basic effective calculus of memetic trait competition and interaction with genes is derived and analyzed. The transient nature of short term memes may be a defense against accumulation of deleterious memes. Horizontally transmitted (panmitic) memes with high spreading rate will often not equalize with a genetic trait, spreading outside of natural selection of the hosts, presenting a cumulative existential threat. Vertical transmission reduces replication rate and allows group selection against deleterious memes. Conclusions: The advantage of a portfolio of groups or species may not accrue to a single group. This analytical understanding elevates meme-risk to the level of a candidate solution to the so-called Fermi Paradox, as interstellar travel might require a planet wide group.
REVIEW | doi:10.20944/preprints202012.0681.v1
Subject: Biology, Anatomy & Morphology Keywords: Fungi; oomycetes; resistance; susceptibility; molecular mechanisms; quantitative trait loci; mapping
Online: 28 December 2020 (11:12:35 CET)
Root rot diseases remain a major global threat to the productivity of agricultural crops. They are usually caused by more than one type of pathogen and are thus often referred to as a root rot complex. Fungal and oomycete species are the predominant participants in the complex, while bacteria and viruses are also known to cause root rot. Incorporating genetic resistance in cultivated crops is considered as the most efficient and sustainable solution to counter root rot; however, resistance is often quantitative in nature. Several genetics studies in various crops have identified quantitative trait loci associated with resistance. With access to whole genome sequences, the identity of the genes within the reported loci is becoming available. Several of the identified genes have been implicated in pathogen response. However, it is becoming apparent that at the molecular level, each pathogen engages a unique set of proteins to either infest the host successfully or be defeated or contained in doing so. In this review, a comprehensive summary of the genes and potential mechanisms underlying resistance or susceptibility against the most investigated root rots of important agricultural crops is presented.
REVIEW | doi:10.20944/preprints202011.0228.v2
Subject: Biology, Anatomy & Morphology Keywords: environmental monitoring; underwater respirometry; fluorometry; photobiology; coral metabolism
Online: 28 December 2020 (03:43:55 CET)
Coral reefs are declining worldwide due to global changes in the marine environment. The increasing frequency of massive bleaching events in the tropics is highlighting the need to better understand the stages of coral physiological responses to extreme conditions. Moreover, like many other coastal regions, coral reef ecosystems are facing additional localized anthropogenic issues such as nutrient loading, increased turbidity, and coastal development. Different strategies have been developed to measure the health status of a damaged reef, ranging from the resolution of individual polyps to an entire coral community, but techniques for measuring coral physiology in situ are not yet widely implemented. For instance, while there are many studies of the coral holobiont response in single or limited-number multiple stressor experiments, they provide only partial insights to metabolic performance under more complex temporally and spatially variable natural conditions. Here, we discuss the current status of coral reefs and their global and local stressors in the context of experimental techniques that measure core processes in coral metabolism (respiration, photosynthesis, and biocalcification) in situ, and their role in indicating the health status of colonies and communities. We highlight the need to improve the capability of in situ studies in order to better understand the resilience and stress response of corals under multiple global and local scale stressors.
Fri, 25 December 2020
HYPOTHESIS | doi:10.20944/preprints202012.0664.v1
Subject: Biology, Anatomy & Morphology Keywords: Crustacea; Anomura; Brachyura; Carcinization; Phylogeny; Convergent evolution; Morphological integration
Online: 25 December 2020 (13:31:09 CET)
A fundamental question in biology is whether phenotypes can be predicted by ecological or genomic rules. For over 140 years, convergent evolution of the crab-like body plan (with a wide and flattened shape, and a bent abdomen) at least five times in decapod crustaceans has been known as ‘carcinization’. The repeated loss of this body plan has been identified as ‘decarcinization’. We offer phylogenetic strategies to include poorly known groups, and direct evidence from fossils, that will resolve the pattern of crab evolution and the degree of phenotypic variation within crabs. Proposed ecological advantages of the crab body are summarized into a hypothesis of phenotypic integration suggesting correlated evolution of the carapace shape and abdomen. Our premise provides fertile ground for future studies of the genomic and developmental basis, and the predictability, of the crab-like body form.
HYPOTHESIS | doi:10.20944/preprints202012.0657.v1
Subject: Biology, Anatomy & Morphology Keywords: monophyly; progenotes; membrane evolution; origin of biological systems
Online: 25 December 2020 (12:29:28 CET)
Cells occupy a prominent place in the history of life on planet Earth. The central role of cellular organization is observed by the fact that “cellular life” is often used as a synonym for life itself. Thus, most characteristics used to define cells overlap with the ones used to define life. Notwithstanding, new scenarios about the origin of life are bringing alternative views to describe how cells may have evolved from the open biological systems named progenotes. Here, using a logical and conceptual analysis, we re-evaluate the characteristics used to infer a single origin for cells. We argue that some evidences used to support cell monophyly, such as the presence of elements from both the translation mechanism and the universality of the genetic code, actually indicate a unique origin for all “biological systems”, a term used to define not only cells, but also virus and progenotes. Besides, we present evidence that at least two biochemical pathways as important as (i) DNA replication and (ii) lipid biosynthesis may not homologous between Bacteria and Archaea. The identities observed between the proteins involved in those pathways along representatives of these two ancestral Domains are too low to indicate common genic ancestry. Altogether these facts can be seen as an indication that cellular organization has possibly evolved two or more times and that LUCA (the Last Universal Common Ancestor) might not have existed as a cellular entity. Thus, we aim to consider the possibility that different strategies acquired by biological systems to exist, such as viral, bacterial and archaeal were originated independently from the evolution of different progenote populations.
ARTICLE | doi:10.20944/preprints202012.0649.v1
Subject: Biology, Anatomy & Morphology Keywords: Ophiura sarsii; the Barents Sea; brittle stars; barcoding; COI gene
Online: 25 December 2020 (10:24:23 CET)
Ophiura sarsii is a common brittle star species across Arctic and subarctic regions of Atlantic and Pacific oceans. In the Barents Sea O. sarsii is among the dominant echinoderms. We studied genetic diversity of O. sarsii by sequencing the 548 bp fragment of mitochondrial COI gene. O.sarsii demonstrated high genetic diversity in the Barents Sea. Both major Atlantic mtDNA lineages were present in the Barents Sea and were evenly distributed between the northern waters around Svalbard archipelago and the southern part near Murmansk coast of Kola Peninsula. Both regions, as well as other parts of the O.sarsii range, were characterized by high haplotype diversity with a significant number of private haplotypes, being mostly satellites to the two dominant haplotypes, each belonging to a different mtDNA clade. Demographic analyses indicated that the demographic and spatial expansion of Ophiura sarsii in the Barents Sea most plausibly has started during the Bølling–Allerød interstadial, during the deglaciation of the western margin of the Barents Sea.
BRIEF REPORT | doi:10.20944/preprints202012.0640.v1
Subject: Biology, Anatomy & Morphology Keywords: breeding; nursery gound; Eubalaena australis; Chile; Humboldt Current System; mark-recapture; drone
Online: 25 December 2020 (07:07:22 CET)
The Chile-Peru subpopulation (CPe) of the southern right whale (Eubalaena australis) is classified as critically endangered following intense whaling in past centuries. Due to their very low abundance, information on breeding and feeding grounds is also scarce. Unmanned aerial vehicles (UAVs) are increasingly applied in marine mammal research thanks to their low cost and relative ease of use. This case study documents a southern right whale nursing in Bahía Moreno (23ºS), Antofagasta, northern Chile, through high-resolution images taken by UAV of a lone adult in July 2019 and the same (photo-identified) whale with a neonate in August, confirming local parturition. Combined with earlier data we hypothesize that the Antofagasta Region may be a calving and nursing ground for the CPe subpopulation. Given the intense shipping traffic and fishing activities around the Mejillones Peninsula and Antofagasta port, priorly recommended marine spatial planning to help avoid net entanglements and vessel collisions of fin and humpback whales would also contribute to the conservation of the CPe stock of southern right whale.
Thu, 24 December 2020
REVIEW | doi:10.20944/preprints202012.0628.v1
Online: 24 December 2020 (13:58:40 CET)
Ruminants perhaps appeared about 50 million years ago (Ma). Five ruminant families had been extinct and about 200 species in 6 ruminant families are living today. The first ruminant family probably was small omnivore without functional ruminal microbiota to digest fiber. Subsequently, other ruminant families evolved around 18-23 Ma along with woodlands and grasslands. Probably, ruminants started to consume selective and highly nutritious plant leaves and grasses similar to concentrates. By 5-11 Ma, grasslands expanded and some ruminants used more grass in their diets with comparatively low nutritive values and high fibers. Historically, humans have domesticated 9 ruminant species that are mostly utilizer of low quality forages for human benefits. Thus, the non-functional rumen microbiota to predominantly concentrate fermenting microbiota, followed by predominantly fiber digesting microbiota had evolved for mutual complementary benefits of holobiont over the million years. The core microbiome of ruminant species seems the resultant of hologenome interaction in an evolutionary unit. The inertia and resilience properties of ruminal ecosystem seem to be due to this core microbiota, which makes the ecosystem most stable in response to perturbations because this core microbiota has evolutionary advantages with logically more generalists (i.e., wide metabolic versatile and redundancy). Also, a part of the ruminal microbiome shows highly plasticity, which is likely useful for evolutionary adaptability of holobiont. This review discusses ecological characteristics of ruminal microbial community in evolutionary perspectives. The updated understanding of ecological traits of ruminal microbiome would be helpful to better modulate the ruminal fermentation favorably for human benefits.
REVIEW | doi:10.20944/preprints202012.0283.v2
Subject: Biology, Animal Sciences & Zoology Keywords: SARS-CoV-2; Covid-19; wildlife; host-switching; reservoirs; risk assessment; surveillance
Online: 24 December 2020 (09:20:20 CET)
The novel coronavirus SARS-CoV-2 likely emerged from a wildlife source with transmission to humans followed by rapid geographic spread throughout the globe and dramatic impacts on both human health and global economies. Since the onset of the pandemic, there have been several instances of human-to-animal transmission involving companion, farmed and zoo animals, and one instance of infection in a wild mink, with the clear potential for further spread into free-living wildlife. The establishment of reservoirs of infection in wild animals would create significant challenges to infection control in humans and could pose a threat to the welfare and conservation status of wildlife. Herein, we discuss the potential for exposure, maintenance and onward transmission of SARS-CoV-2 in an initial selection of wild and feral species (bats, canids, felids, mustelids, great apes). Targeted surveillance and dynamic risk assessment are important tools for the early detection of infection in wildlife and a means of collating and synthesising emerging information in a rapidly changing situation. Such efforts should be integrated with public health information to provide insights into the potential role of wild mammals in the continuing epidemiology of SARS-CoV-2. This approach should also be adopted to address the wider need to proactively assess threats to human and animal health from other diseases that may emerge from wildlife.
Wed, 23 December 2020
ARTICLE | doi:10.20944/preprints202012.0593.v1
Subject: Biology, Entomology Keywords: epidemiology; X23; fatalities; venomous animals; Spain; stings; hornets; wasps; bees; Vespa velutina
Online: 23 December 2020 (15:24:07 CET)
Epidemiology of fatalities in Spain due to hornet, wasp and bee stings (Cause Code of Death: X23) is described. Over a 20-year period (1999-2018), a total of 78 fatalities were recorded, mostly occurring in males (85.9%), of 65 years and older (52.6%), at “unspecified places” (67.9%) and in the months of July and August (50%). The X23 mortality rates (X23MR) expressed in terms of annual rates and per million inhabitants, varied from 0.02 to 0.19 (mean value ± standard deviation = 0.09 ± 0.05), placing Spain at low levels in comparison with other countries. A more detailed and specific breakdown of the distribution of the yearly deaths at Sub-state level and across communities reveals some striking features. They were more concentrated in the Communities of Galicia (35.8%), Andalucía (21.7%) and Castilla y León (12.8%). X23MR were estimated in Galicia at 1.82, 1.10 and 2.22 in 2014, 2016 and 2018 respectively; and in Asturias at 1.88 and 0.97, in 2014 and 2017 respectively. The role of the invasive species Vespa velutina (VV), is examined. Due to its habits, abundance and broader distribution, the risk that VV represents to human health is unmatched by other Hymenoptera native species.
ARTICLE | doi:10.20944/preprints202012.0581.v1
Online: 23 December 2020 (09:56:25 CET)
Celiac disease (CD) is a permanent intolerance to dietary protein, gluten, from wheat rye and barley. It occurs in about 1% worldwide population, in genetically predisposed individuals bearing human leukocyte antigen (HLA) DQ2/DQ8. Gut epithelial cell stress and innate immune activation are responsible for breaking oral tolerance to gliadin, the gluten component. To date, the only treatment available for CD is a long-term gluten-free diet. Several evidences show that an altered composition of the intestinal microbiota (dysbiosis) could play a key role in the pathogenesis of CD, through the modulation of intestinal permeability and the regulation of the immune system. Here we show that gliadin induces a chronic ER stress condition in the small intestine of a CD mouse model and that the co-administration of probiotics efficiently attenuates both UPR and gut inflammation. Moreover, the composition of probiotics formulations might differ in their activity at molecular level, especially toward the three axes of the UPR. Therefore, rebalancing the gut microbiota composition by probiotics administration might rep-resent a new strategy to treat CD affected patients.
Tue, 22 December 2020
ARTICLE | doi:10.20944/preprints202012.0551.v1
Subject: Biology, Anatomy & Morphology Keywords: Enterohemorrhagic Escherichia coli O157: H7; EspF; SMC1; CoIP-MS; DNA damage
Online: 22 December 2020 (10:33:53 CET)
The enterohemorrhagic Escherichia coli (EHEC) O157: H7 EspF is known to be a multifunctional effector that triggers several damage processes in the host cells. However, in the process of EHEC O157: H7 infection, the interactions between EspF, its N- or C-terminus, and host proteins are still unclear. In this work, we use co-immunoprecipitation combined with mass spectrometry (CoIP-MS) to screen the interactions between EspF/EspF-N/EspF-C terminus and host proteins. A total of 311 host proteins are analyzed. The N-terminus of EspF is found to interact with 192 proteins, whereas 205 proteins interact with the C-terminus. These proteins are mainly involved in RNA splicing, endoplasmic reticulum stress, and a variety of metabolic signaling pathways. Surprisingly, MS results reveal that EspF can also phosphorylate H2AX, suggesting that EspF may directly mediate DNA damage. Here, by western blot and immunofluorescence (IF), we verified that EspF can cause phosphorylation of H2AX and mediates cell multi-nuclearation and cell hypertrophy. Furthermore, we verify here for the first time that SMC1 interacts with EspF -C-terminus, and provide evidence that EspF increases p-SMC1 levels. p-SMC1 is known to influence S-phase cell cycle arrest and usually increases during periods of DNA damage. Our work revealed a novel interaction between EspF and the host protein SMC1 and lays a foundation for further research on EspF-mediated host DNA damage, apoptosis, and even colorectal carcinogenesis.
ARTICLE | doi:10.20944/preprints202012.0545.v1
Subject: Biology, Horticulture Keywords: LCIA; plant protection; compost; sustainable greenhouse production
Online: 22 December 2020 (09:32:12 CET)
Italian floriculture is facing structural changes. Possible options to maintain competitiveness of the involved companies include promotion of added values, from local productions to environmental sustainability. To quantify value and benefits of cleaner production processes and choices, a holistic view is necessary, and could be provided by life cycle assessment (LCA) methodology. Previous studies on ornamental products generally focused on data from one company or a small sample. The aim of this study was a gate-to-gate life cycle assessment of two ornamental species (Cyclamen persicum Mill. and Pelargonium ×hortorum Bailey) using data from a sample of 20 companies belonging to a floriculture district in Treviso, Veneto region. We also assessed the potential benefits for the environmental impact of the selected species of alternative management choices regarding plant protection and reuse of composted waste biomass. Life cycle impact assessment showed the higher impact scores for the zonal geranium, mainly as a consequence of greenhouse heating with fossil fuels. This factor, along with higher uniformity of production practices and technological level of equipment, translated in lower variability observed in comparison with cyclamen production, which shows a wider results range, in particular for eutrophication, acidification and human toxicity potentials. The application of integrated pest management had significant benefits in terms of impact reduction for acidification and human toxicity of cyclamen, while reduced use of mineral nutrients through compost amendment of growing media resulted in a reduced eutrophication potential. The achievable benefits for zonal geranium were not observable because of the dominant contribution of energy inputs.
REVIEW | doi:10.20944/preprints202012.0544.v1
Subject: Biology, Anatomy & Morphology Keywords: adult neurogenesis; brain injury; neural stem cell; regeneration; stroke; zebrafish; mice
Online: 22 December 2020 (08:49:39 CET)
Adult neurogenesis is an evolutionary conserved process occurring in all vertebrates. However, striking differences are observed between the taxa, considering the number of neurogenic niches, the neural stem cell (NSC) identity and brain plasticity under constitutive and injury-induced conditions. Zebrafish has become a popular model for the investigation of the molecular and cellular mechanisms involved in adult neurogenesis. Compared to mammals, the adult zebrafish displays a high number of neurogenic niches distributed throughout the brain. Furthermore, it exhibits a strong regenerative capacity without scar formation or any obvious disabilities. In this review, we will first discuss the similarities and differences regarding (i) the distribution of neurogenic niches in the brain of adult zebrafish and mammals (mainly mouse) and (ii) the nature of the neural stem cells within the main telencephalic niches. In the second part, we will describe the cascade of cellular events occurring after telencephalic injury in zebrafish and mouse. Our study clearly shows that most early events happening right after the brain injury are shared between zebrafish and mouse including cell death, microglia and oligodendrocyte recruitment, as well as injury-induced neurogenesis. In mammals one of the consequences following an injury is the formation of a glial scar that is persistent. This is not the case in zebrafish, which may be one of the main reasons that zebrafish display a higher regenerative capacity.
Mon, 21 December 2020
ARTICLE | doi:10.20944/preprints202012.0542.v1
Subject: Biology, Anatomy & Morphology Keywords: leaf surface; soil surface cover; growth rate; nitrogen leaf content; SPAD; triangular greenness index (TGI)
Online: 21 December 2020 (18:50:21 CET)
Management practices must be developed to improve yam production sustainability. Image-based phenotyping techniques could help developing such practices based on non-destructive analyses of important plant traits. Our objective was to determine the potential of image-based phenotyping methods to assess traits relevant for tuber yield formation in yam grown in glasshouse and field. We took plant and leaf pictures with consumer cameras. We used the numbers of image pixels to derive the shoot biomass and the total leaf surface and calculated the ‘triangular greenness index’ (TGI) which is an indicator of the plant nitrogen (N) nutritional status. Under glasshouse conditions, the number of pixels obtained from nadir view (image taken top down) was positively correlated to the shoot biomass, and the total leaf surface, while the TGI was negatively correlated to the N content of diagnostic leaves. Under field conditions, pictures taken from the nadir view showed an increase in soil surface cover and a decrease in TGI with time. TGI was negatively correlated to SPAD measured on specific leaves but was not correlated to the N content of these leaves. In conclusion, these phenotyping techniques deliver relevant results but need to be further developed and validated for application in yam.
Online: 21 December 2020 (11:29:19 CET)
The history of life on Earth has been shaped by a series of major evolutionary innovations. While some of these innovations occur repeatedly (e.g., multicellularity), some of the most important evolutionary innovations (e.g., the origin of life itself, eukaryotes, or the genetic code) are evolutionary singularities, arising just once in the history of life. This historical fact has often been interpreted to mean that singularities are particularly difficult, low-probability evolutionary events, thus making the long-term course of life on Earth highly contingent on their chance appearances. Alternatively, singularities may arise from evolutionary priority effects, where first-movers suppress independent origins. In this paper, we disentangle these hypotheses by examining a distinctive innovation: phototrophy. The ability to use light to generate metabolic energy evolved twice, preserving information about the evolution of rare, transformative innovations that is lost in singularities. We show that the two forms of phototrophy occupy opposite ends of several key trade-offs: efficiency of light capture vs. return on investment in photosynthetic infrastructure, dependence on limiting nutrients vs. metabolic versatility, and complexity vs. simplicity. Our results suggest that phototrophy is a 'dual singularity' because phototrophic niche space is too large for the first mover to fully suppress future innovation, but not so large as to support many innovations. While often ignored over geological time scales, ecological interactions, in particular the potential for direct competition and priority effects, plays a fundamental role in the tempo and mode of major evolutionary innovations.
ARTICLE | doi:10.20944/preprints202012.0502.v1
Subject: Biology, Anatomy & Morphology Keywords: invasive species; ecological niche models; species distribution models; vector surveillance
Online: 21 December 2020 (10:50:19 CET)
Aedes scapularis is a neotropical mosquito known to transmit pathogens of medical and veterinary importance. Its recent establishment in southeastern Florida has potential public health implications. We used an ecological niche modeling approach to predict the abiotic environmental suitability for Ae. scapularis across much of the Americas and Caribbean Islands. Georeferenced occurrence data obtained from the Global Biodiversity Inventory Facility and recent collection records of Ae. scapularis from southern Florida served as input for model calibration. Environmental layers included bioclimatic variables provided in 2000 to 2010 average Modern Era Retrospective-analysis for Research and Applications climatic (MERRAclim) data. Models were run in the software program Maxent. Isothermality values found often in costal environments contributed strongest to model performance. Model projections suggested areas predicted suitable for Ae. scapularis across portions of the Amazon Basin, the Yucatán Peninsula, the Florida Peninsula, and multiple Caribbean Islands. Additionally, model predictions suggested connectivity of highly suitable or relatively suitable environments spanning the United States Gulf Coast, which may facilitate geographic expansion of this species. At least sixteen Florida counties were predicted highly suitable for Ae. scapularis, suggesting vigilance is needed by vector control and public health agencies to recognize further spread of this vector.
ARTICLE | doi:10.20944/preprints202012.0491.v1
Subject: Biology, Anatomy & Morphology Keywords: fluctuating asymmetry; ground beetles; morphometric variation; biotope impact; species*biotope interaction; negative relationship between dimensional and meristic traits
Online: 21 December 2020 (10:16:14 CET)
In our study we used the data set on morphimetric traits in beetles species. It has been constantly replenishing for 20 years by the samples, received from different regions of Russia and abroad. In this case we have selected data on nine species for which the left and right sides had been measured and fluctuating asymmetry (FA) could be estimated. The samples were from 6 provinces of Russia and Belarus, which ranged in 3 degrees in latitude and 57 degrees in longitude and included more than 150 plots in different types of biotopes. FA was assessed according to the standard method in 5265 specimen in one dimensional trait and one - meristic. ANOVA showed that biotope, species and their interaction affected FA in both traits, that is different species reacted differently to biotope type. In uncommon biotopes (according to accepted in carabidology classification) FA was increased. In forest species the negative relationship between FA in dimensional and meristic traits in the range in biotopes was revealed. In those species only FA values were higher in males than in females. In generalist species FA varieв similarly in both sexes and in both traits being the highest in open biotopes. In eudomonant of arable lands biotopes – Poecilus cupreus – the highest values of FA were recorded in the meadows, being about equal in all types of crops.
Fri, 18 December 2020
ARTICLE | doi:10.20944/preprints202012.0476.v1
Subject: Biology, Anatomy & Morphology Keywords: Ovarian cancer; mapping-based; mapping-free; SNVs; survival prognosis
Online: 18 December 2020 (15:15:50 CET)
Ovarian cancer is the most frequent cause of deaths in gynecologic malignancies. Many possible mechanisms have been proposed via RNAseq and DNAseq technique recently. However, the driving factors are still obscure. The possible reasons are attributed to the incomplete human reference. This study integrated the canonical mapping-based and mapping-free protocols to extract reliable variations and novel events. We eventually obtained 450 reliable SNVs from the WES data and novel events from the RNAseq data, including 154 SNVs, 462 intron events, two repeats and six splice events. We identified six differentially expressed genes and six contigs that are significantly related to survival prognosis. The recurrent SNVs in significantly differentially expressed genes can be validated in an independent cohort of 20 Chinese ovarian cancer patients.
HYPOTHESIS | doi:10.20944/preprints202012.0470.v1
Online: 18 December 2020 (14:03:16 CET)
Ancient DNA has given a new vision to the recent history of human evolution. However, by always relying on the information provided by whole genome sequencing, some relevant relationships between modern humans and its archaic relatives have been misinterpreted by hybridization and recombination causes. In contrast, the congruent phylogeny, obtained from non-recombinant uniparental markers, indicates that humans and Neanderthals are sister subspecies, and that the most recent common ancestor of modern humans was not of African origin but Eurasian.
ARTICLE | doi:10.20944/preprints202012.0464.v1
Subject: Biology, Ecology Keywords: picoides dorsalis; old-growth forest; forest management; conservation; protected areas; boreal forest; clear-cutting
Online: 18 December 2020 (12:03:01 CET)
The southern extent of the boreal forest in North America has experienced intensive human disturbance in the past decades. Among these, forest harvesting leads to the substantial loss of late-successional stands that include key habitat attributes for several avian species. The American Three-toed Woodpecker, Picoides dorsalis, is associated with continuous old spruce forests in the eastern part of its range. In this study, we assess the influence of habitat characteristics at different scales on the occupancy of American Three-toed Woodpecker in a heavily managed boreal landscape of northeastern Canada, and we inferred species occupancy at the regional scale. We conducted 185 playback stations over two breeding seasons and modelled the occupancy of the species while taking into account the probability of detection. American Three-toed Woodpecker occupancy was lower in stands with large areas recently clear-cut, and higher in landscapes with large extents of old-growth forest dominated by black spruce. At the regional scale, areas with high probability of occupancy were scarce and mostly within protected areas. Habitat requirements of the American Three-toed Woodpecker during the breeding season, coupled with over-all low occupancy rate in our study area, challenge its long-term sustainability in such heavily managed landscapes. Additionally, the scarcity of areas of high probability of occupancy in the region suggest that the ecological role of old forest outside protected areas could be compromised.
ARTICLE | doi:10.20944/preprints202012.0462.v1
Subject: Biology, Anatomy & Morphology Keywords: Bergmann’s rule; carapace morphometry; plastron scutes; Hermann’s tortoises; Testudo hermanni boettgeri
Online: 18 December 2020 (11:56:04 CET)
Testudines show phenotypic plasticity, and variation among specific populations within a species is widespread. Morphological differences between populations reflect ecological factors that drive adaptation to local conditions. In this context, gathered basic data on morphology of the Hermann’s tortoise (Testudo hermanni boettgeri) to document their variation across different geographical regions. We surveyed Hermann’s tortoises, in five different locales within Albania during April and May 2020 and measured 20 morphological characteristics, including carapace and plastron dimensions. We measured 188 tortoises (81 males, 107 females) in this study, and females were larger (P=.0001) and heavier (P=.0001) than males. Mean straight carapace length [SCL] and body mass were = 172.4 mm and 1128.8 g, respectively, for females and 151.3 mm and 735 g, respectively, for males. The overall Albanian T. h. boettgeri population were regionally diverged into 3 different populations that were situated in northern (Shkodra), central (Tirana, Berati and Ballshi) and southern (Saranda) Albania. The body size (curved carapace length; CCL) of females was positively correlated (r=0.216; P=0.025) with the latitude degree, in accordance with Bergmann's rule. However, there was no correlation between body size and degrees north latitude in males. These striking regional differences among Albanian T. h. boettgeri strongly suggest that further study of molecular variations in and reproductive output of Hermann’s tortoises is warranted.
ARTICLE | doi:10.20944/preprints202012.0454.v1
Subject: Biology, Entomology Keywords: Head lice, haplogroup E, PHUM540560 gene, Acinetobacter haemolyticus, Acinetobacter spp., Guinea.
Online: 18 December 2020 (11:22:55 CET)
Pediculus humanus capitis, the head louse, is an obligate blood-sucking ectoparasite that occurs in six divergent mitochondrial haplogroups (A, D, B, F, C and E), each exhibiting a particular geographic distribution. A few years ago, several studies reported the presence of different pathogenic agents in head lice specimens from different clades collected worldwide. These findings suggest that head louse could be a vector for dangerous diseases and therefore a serious public health problem. Herein, we aimed to study the mitochondrial genetic diversity, the PHUM540560 gene polymorphisms profile of head lice collected in Guinea, as well as to screen for the pathogens present in these lice. In 2018, a total of 155 head lice were collected from 49 individuals at the Medicals Centers of rural (Maférinyah village) and urban (Kindia city) areas, in Guinea. All head lice were subjected to genetic analysis and screened for the presence of several pathogens using molecular tools. The results showed that all head lice belonged to the haplogroups C/E using the duplex qPCR which detects both clades. Standard PCR and sequencing revealed that all specimens belonged to the haplogroup E, including 8 haplotypes, whither 6 new identified for the first time in this study. The study of the PHUM540560 gene polymorphisms in our Guinean head lice revealed that 7/40 (17.5%) of our tested samples exhibit three different polymorphism profiles compared to the clade A-head lice PHUM540560 gene profile, while the remaining specimens 33/40 (82,5%) showed the same PHUM540560 gene polymorphism profile as the previously reported clade A-body lice. Molecular investigations of the targeted pathogens revealed only the presence of Acinetobacter species in 9% of our samples using real time PCR. Sequencing results identified highlighted the presence of several Acinetobacter species, including Acinetobacter baumannii (14.3%), Acinetobacter nosocomialis (14.3%), Acinetobacter variabilis (14.3%), Acinetobacter haemolyticus (7.2%), Acinetobacter towneri (7.2%). Furthermore, a candidate new species of Acinetobacter sp. (7.2%) was detected. Positive specimens were collected from 24,5% individuals in Maférinyah. We also investigated in our study the carbapenem’s-resistant profile of A. baumannii, none of our specimens were positive for the following resistance genes blaOXA-21, blaOXA-24 and blaOXA-58. To the best of our knowledge, our study is the first to report the existence of the Guinean haplogroup E, the PHUM540560 gene polymorphism profile as well as the presence of Acinetobacter species in head lice collected from Guinea.
ARTICLE | doi:10.20944/preprints202012.0453.v1
Subject: Biology, Anatomy & Morphology Keywords: Actinidia arguta; leaf; bioactivity; antioxidant activity; LC-MS/MS
Online: 18 December 2020 (11:14:24 CET)
Actinidia arguta (Sieb. et Zucc.) Planch. ex Miq. is abundant of vitamin C and bioactive compounds with high antioxidant activities. In this study, eight wild A. arguta accessions from different areas in Northeast China were collected. Some bioactive compounds were examined on the different tissues of different germplasms including four kinds of leaves, petioles and fruits. The method of UPLC-MS was used to detect the flavonoid compounds. The results showed that some bioactive compounds including vitamin C, soluble sugar, free amino acid, total phenolics and flavonoids content showed significant differences between six tissues of A. arguta accessions and showed significant variability with maturity. In eight accessions, the highest vitamin C content was found in young apical leaves of ‘CBS-6’ (7.47 mg/g fresh weight), and the highest soluble sugar content was in fruits of ‘CJ-1’ (196.52 mg/g fresh weight) and the highest total phenolic content and total flavonoids content were in young apical leaves of ‘CBS-11’ (3.48 mg/g fresh weight) and of ‘CBS-3’ (2.00 mg/g fresh weight), respectively. Ten flavonoid compounds including kaempferol, isorhamnetin and quercetin were detected in leaves, petioles and fruits. The total content of flavonoids were highest in young apical leaves (10219.84 µg·g-1) and the lowest in fruits (78.75 µg·g-1). Based on the comparison of the contents of several bioactive compounds, the two accessions ‘CJ-1’ and ‘CBS-8’ had relatively outstanding performance, and in the comprehensive evaluation of the antioxidant activity among different tissues, the young leaves had the strongest antioxidant activity. These results highlighted the antioxidant potentialities of A. arguta leaves as a major source of phenolics and vitamin C as well as flavonoids. It provided a theoretical basis for the utilization of leaves of A. arguta.
ARTICLE | doi:10.20944/preprints202012.0449.v1
Subject: Biology, Anatomy & Morphology Keywords: climate change; crop pollination; functional traits; global warming; pollination; seed production; self-incompatibility; Sinapis alba
Online: 18 December 2020 (08:55:25 CET)
Climate change is likely to have a complex effect on the growth of plants, their phenology, plant-pollinator interactions, and reproductive success. Therefore, we tested the impact of three key factors (temperature, water, and nitrogen supply) on traits, pollination, and seed production in Sinapis alba (Brassicaceae). We grew the plants in different combinations of temperature, water, and nitrogen supplementation, measured multiple vegetative and floral traits, and assessed the response of pollinators in the field. We also evaluated the effect of growing conditions on seed set in plants exposed to pollinators and hand-pollinated plants. Our results show that water stress impaired vegetative growth, decreased flower production, reduced visitation by pollinators and seed set, while nitrogen availability played an important role in nectar production. Temperature modulated the effect of water and nitrogen availability on vegetative and floral traits and strongly affected flowering phenology and flower production. We demonstrated that changes in temperature, water, and nitrogen availability induce changes in plant vegetative and floral traits which impact flower visitation and consequently plant reproduction. Climate change, particularly increasing temperature combined with reduced precipitation, thus may impact plant-pollinator interactions with negative consequences for the reproduction of wild plants and insect-pollinated crops.
ARTICLE | doi:10.20944/preprints202012.0446.v1
Subject: Biology, Anatomy & Morphology Keywords: Megaptera novaeangliae; feeding grounds; trap-feeding; lunge-feeding; Humboldt Current; Peruvian anchovy; phylopatry
Online: 18 December 2020 (08:25:48 CET)
Humpback whales perform long migrations from their breeding and nursing areas at low latitudes to feeding grounds at high latitudes. Nonetheless this strictly dichotomous paradigm of migration is challenged by accumulating examples of occasional or regular feeding in tropical or subtropical areas for several stocks worldwide. Here we report multiple lines of evidence of IWC ‘Stock G’ humpback whales feeding in coastal waters at low latitudes of the Southeast Pacific Ocean. Lunge-feeding behavior was observed in Ecuador, while both lunge- and trap-feeding in pursuit of Peruvian anchovy was documented in northern Chile. Five records of substantial defecation in a key breeding ground in Ecuador also demonstrates local foraging. In addition mark-recapture analysis of one individual feeding at high and mid latitudes of Chile suggested potential site fidelity to two foraging areas. Whether these behaviors are novel due to changes in prey distribution, intensifying competition for food from a growing humpback whale population, or rather reflect vastly increased research effort in a poorly studied region, remains unknown. Further research into the feeding ecology of 'Stock G' should help reveal historic and potentially novel feeding grounds, prey composition and precise migration paths.
ARTICLE | doi:10.20944/preprints202012.0444.v1
Subject: Biology, Anatomy & Morphology Keywords: novel rumen yeast; screening; isolation; biomass of yeast; cellulase enzyme
Online: 18 December 2020 (07:26:28 CET)
We hypothesized that rumen fluid with yeast producing cellulase enzyme can occur and also produces a high biomass compared to S. cerevisiae. Therefore, the aim of this study was to screen and isolate yeast from rumen fluids with an experimental design method. We optimized a fermentation medium containing sugarcane molasses as a carbon source and urea as a nitrogen source to measure the efficiency of biomass production and cellulase activity. Two fistulated-crossbred Holstein Friesian steers, averaging 350 ± 20 kg body weight, were used to screen and isolate ruminal yeast. The two experiments were designed. A 12 × 3 × 3 factorial was used in a completely randomized design to determine biomass and carboxymethyl cellulase activity. Factor A was isolated yeasts and S. cerevisiae. Factor B was sugarcane molasses (M) concentration. Factor C was urea (U) concentration. Potential yeast was selected for identified and analyzed as a 4 × 3 factorial use in a completely randomized design including. Factor A was incubation times. Factor B was isolated yeast strains including code H-KKU20 (as P. kudriavzevii-KKU20), I-KKU20 (C. tropicalis-KKU20), and C-KKU20 (as Galactomyces sp.-KKU20). Isolation was under aerobic conditions, resulting in a total of 11 different colonies. We noted two appearances of colonies including, asymmetric colonies of isolated yeast (indicated as A, B, C, E, and J) and ovoid colonies (coded as D, F, G, H, I, and K). The highest biomass was observed in three yeasts including codes H, I, and C-KKU20 when inoculated in 25% molasses with 1% urea (M25+U1) (p <0.01). The highest CMCase activity was observed in yeast code H-KKU20 when inoculated in all media solutions (p <0.01). Ruminal yeasts strains H-KKU20, I-KKU20, and C-KKU20 were selected for their ability to produce biomass and their CMCase enzyme synthesis. Identification of isolates H-KKU20 and I-KKU20 revealed that those isolates belonged to Pichia kudriavzevii-KKU20 and Candida tropicalis-KKU20, while C-KKU20 was identified as Galactomyces sp.-KKU20. Two strains provided maximum cell growth: P. kudriavzevii-KKU20 (9.78 and 10.02 Log cell/ml) and C. tropicalis-KKU20 (9.53 and 9.6 Log cells/ml) at 60 and 72 h of incubation time, respectively. The highest ethanol production was observed in S. cerevisiae: 76.4, 77.8, 78.5, and 78.6 g/L at 36, 48, 60, and 72 h of incubation time, respectively (p <0.01). The P. kudriavzevii-KKU20 yielded the least reducing sugar about 30.6 and 29.8 g/L at 60 and 72 h of incubation time, respectively. It could be concluded that screening and isolating yeast from rumen fluids resulted in 11 different characteristics of yeasts. The first novel yeasts discovered in the rumen fluid of cattle were Pichia kudriavzevii-KKU20, Candida tropicalis-KKU20, and Galactomyces sp.- KKU20. P. kudriavzevii-KKU20 had higher results than the other yeasts in terms of biomass production, cellulase enzyme activity, and cell number.
Thu, 17 December 2020
ARTICLE | doi:10.20944/preprints202012.0438.v1
Subject: Biology, Anatomy & Morphology Keywords: reflectance; hyperspectral imaging; pigments; damages; apple fruit
Online: 17 December 2020 (16:08:39 CET)
Reflected light carries ample information about biochemical composition, tissue architecture, and physiological condition of plants. Recent technical progress brought about affordable imaging hyperspectrometers (IH) providing spatially resolved spectral data on plants. The extraction of sensible information from hyperspectral reflectance images is difficult due to inherent complexity of plant tissue and canopy optics, especially when recorded by IH under ambient sunlight. We aimed at obtaining a deeper insight into plant optics as perceived by IH since there is a high demand for algorithms for fruit harvesting and grading systems equipped with computer vision and robotic systems capable of working in orchard. We report on the characteristic changes in hyperspectral reflectance accompanying the accumulation of anthocyanins in healthy fruit, pigment breakdown during sunscald and phytopathogen attacks. The measurements made outdoors with a snapshot IH were compared with traditional “point” reflectance measured with a conventional spectrophotometer under controlled illumination conditions. Most of the spectral features and patterns of plant reflectance were evident in the IH-derived reflectance images. As a step forward, a novel index for highlighting tissue damages on the background of the anthocyanin absorption, BRI-M = (1/Rorange – 1/Rred + 1/RNIR), is suggested. Difficulties of the interpretation of fruit hyperspectral reflectance images recorded in situ are discussed with possible implications for plant physiology and precision horticulture practices.
ARTICLE | doi:10.20944/preprints202012.0422.v1
Subject: Biology, Anatomy & Morphology Keywords: Fresh cassava root; pellet containing high sulfur; ruminal characteristics; blood thiocyanate; Thai native beef cattle
Online: 17 December 2020 (09:16:26 CET)
The objective of this experiment was to study the effect of feeding pellet containing high sulfur (PELFUR) diet and fresh cassava root (FCR) to Thai native beef cattle on feed use efficiency, ruminal characteristics, and blood metabolites. Four male Thai native beef cattle (150 ± 15.0 kg of body weight (BW)) were allocated with a 2 × 2 factorial arrangement in a 4 × 4 Latin square design. Factor A was FCR supplementation at 15 and 20 g/kg of BW. Factor B was the sulfur level in the PELFUR ration at 15 and 30 g/kg of dry matter (DM). No interaction effect was found among FCR supplementation and PELFUR in terms of feed intake and nutrient intake (p > 0.05). Cyanide intake was significantly increased based on FCR supplementation (p < 0.05), whereas sulfur intake was increased by level addition of PELFUR levels (p < 0.05). There were interaction effects among FCR supplementation and PELFUR on digestibility coeﬃcients of DM and organic matter (OM) (p < 0.05). FCR supplementation at 20 g/kg BW with PELFUR 30 g/kg demonstrated the highest digestibility of DM and OM. Moreover, interactions were observed between FCR and PELFUR for bacterial populations (p < 0.01). The populations of bacteria were highest in FCR supplementation at 20 g/kg BW with PELFUR 30 g/kg at various feeding times. An interaction effects from among feeding FCR with PELFUR was found on blood thiocyanate concentrations at various feeding times (p < 0.01). The highest mean values of blood thiocyanate were observed when feeding FCR at 20 g/kg BW with PELFUR at 30 g/kg. No interaction effect was found between FCR and PELFUR on total volatile fatty acids (VFA) and their profiles (p >0.05). However, the proportions of the total VFA at 0 and 4 h post-feeding were increased when FCR at 20 g/kg BW was supplemented (p < 0.01). FCR at 20 g/kg BW could enhance propionate (C3) at 4 h post-feeding when compared with FCR at 15 g/kg BW (p < 0.01). Moreover, supplementation of PELFUR at 30 g/kg increased the total VFA at 0 and 4 h post-feeding, whereas the concentration of C3 at 4 h post-feeding was enhanced (p < 0.05). However, no significant changes were found for any parameters among treatments and between the main effect of FCR and PELFUR supplementation (p > 0.05). In conclusion, feeding of two combinations (FCR 20 g/kg BW with PELFUR 30 g/kg) could promote the nutrient digestibility, the bacterial populations, and the rate of disappearance of cyanide without having any adverse effect on rumen fermentation.
Wed, 16 December 2020
ARTICLE | doi:10.20944/preprints202012.0408.v1
Online: 16 December 2020 (13:11:26 CET)
This experiment was carried out to determine the overall prevalence of pigeon diseases and especially emphasized on prevalence of parasitic diseases in study areas. During this study 45 farms were selected which have >20 pair of pigeon for commercial and >10 pair pigeon for traditional farm in the three study area namely Rajshahi, Natore and Pabna district of Bangladesh. The data were collected from different farm within the study area through a questionnaire and interview schedule with the farm owners. During one year of study period a total Out of 3677 pigeon, positive case in cage of external parasites were 722 and internal parasite positives 114 from 263 fecal sample. The overall prevalence of gastrointestinal and external parasites in pigeon at northern Bangladesh is obtained. The infestation of lice Columbaecula columbae and fly Pseudolynchia canariensis were observed 18.08% and 1.55% respectively. The present study found two species of ectoparasites lice and fly. Diversity of ectoparasite in birds infestation may be depend on many factors, which may include home range, behavior, size and roosting habit of the host. The overall prevalence of gastrointestinal parasites in pigeon are founded that 43.34% in research area. Specific incidence was 22.81% in Ascariasis, 18.63% in Capilariasis and 1.90% in Raillietina parasite in pigeon. Ascaridia colombae is one of the most common (22.81%) helminth species in pigeons in this study. The effect of breed of pigeon observed in present studies the highest in indigenous (63.47%) and lowest exotic (36%) prevalence of gastrointestinal parasite was observed. The specific percentages of Ascariasis, Capilariasis and Raillatina gastrointestinal parasites of pigeon were found 20% & 31.74%; 14% & 30.15% and 2% & 1.58% in exotic & indigenous breed, respectively. In the present study, there is a relation between the occurrence of gastrointestinal parasitic infections with the age of the pigeons which showed that high prevalence in adults (50%) and compare to young (22.22%). but it was statistically significant (P>0.05). In relation with farming system the gastrointestinal parasitic incidence of pigeon was observed in modern and tradition farming system, the highest incidence was 71.16% in traditional & lowest 31.14% in modern farming. When observed specifically in Ascariasis, Capillariasis & Raillietina were 16.39% & 37.41%; 13.11% & 31.25% and 1.63% & 2.5% in modern & traditional, respectively. The effect of regions on the prevalence of gastrointestinal parasites in pigeon was observed in Pabna (68.32%), Natore (57.84%) and Rajshahi (33.33%). The specific percentages of Ascariasis, Capilariasis and Raillatina gastrointestinal parasites of pigeon were 18.18%, 33.33% & 26.31%; 14.54%, 33.33% & 23.38% and 0.606%, 1.66% & 7.89% in Rajshahi, Pabna and Natore, respectively.
ARTICLE | doi:10.20944/preprints202012.0407.v1
Subject: Biology, Anatomy & Morphology Keywords: Endophyte; Aspergillus ochraceus; antifungal; neoaspergillic acid; ixodicidal; mellein
Online: 16 December 2020 (12:18:34 CET)
In the current study, an ethyl acetate extract from the endophytic fungus Aspergillus ochraceus SPH2 isolated from the stem parts of the endemic plant Bethencourtia palmensis was screened for its biocontrol properties against plant pathogens (Fusarium moniliforme, Alternaria alternata and Botrytis cinerea), insect pests (Spodoptera littoralis, Myzus persicae, Rhopalosiphum padi), plant parasites (Meloidogyne javanica) and ticks (Hyalomma lusitanicum). SPH2 gave extracts with strong fungicidal and ixodicidal effects at different fermentation times. The bioguided isolation of these extracts gave compounds 1-3. Mellein (1) showed strong ixodicidal effects and was also fungicidal. This is the first report on the ixodicidal effects of 1. Neoaspergillic acid (2) showed potent antifungal effects. Compound 2 appeared during the exponential phase of the fungal growth while neohydroxyaspergillic acid (3) appeared during the stationary phase, suggesting that 2 is the biosynthetic precursor of 3. Additional molecular ions compatible with pyrazynes that were detected during the exponential phase included flavacol, and aspergilliamide while ochramide A was mostly detected during the stationary phase of the fermentation. Moreover, polyketids were also detected during the sationaty phase of the fermentation curve (dihydroaspyrone, aspyrone, asperlactone) and the alkaloid circumdatin H. Ochratoxin A was not detected. Therefore, SPH2 could be a potential biotechnological tool for the production of ixodicidal mellein.
Tue, 15 December 2020
Subject: Biology, Other Keywords: SARS-CoV-2; COVID-19 pandemic; food industry; disinfection trade-offs; one-health
Online: 15 December 2020 (12:58:18 CET)
Industries of the food sector have made a great effort to control SARS-CoV-2 indirect transmission, through objects or surfaces, by updating cleaning and disinfection protocols previously focused on inactivating other pathogens, as well as food spoilage microorganisms. The information, although scarce at the beginning of the COVID-19 pandemic, has started to be sufficiently reliable to avoid over-conservative disinfection procedures. This work reviews the literature to propose a holistic view of the disinfection process where the decision variables, such as type and concentration of active substance, are optimised to guarantee the inactivation of SARS-CoV-2 and other usual pathogens and spoilage microorganisms while minimising possible side-effects on the environment and animal and human health.
Subject: Biology, Anatomy & Morphology Keywords: multi-level convergence; evolution; bioluminescence; biological organization; complex trait
Online: 15 December 2020 (10:20:12 CET)
Evolutionary convergence provides natural opportunities to investigate how, when, and why novel traits evolve. Many convergent traits are complex, highlighting the importance of explicitly considering convergence at different levels of biological organization, or ‘multi‐level convergent evolution’. To investigate multi‐level convergent evolution, we propose a holistic and hierarchical framework that emphasizes breaking down traits into several functional modules. We begin by identifying long‐standing questions on the origins of complexity and the diverse evolutionary processes underlying phenotypic convergence to discuss how they can be addressed by examining convergent systems. We argue that bioluminescence, a complex trait that evolved dozens of times through either novel mechanisms or conserved toolkits, is particularly well suited for these studies. We present an updated estimate of at least 94 independent origins of bioluminescence across the tree of life, which we calculated by reviewing and summarizing all estimates of independent origins. Then, we use our framework to review the biology, chemistry, and evolution of bioluminescence, and for each biological level identify questions that arise from our systematic review. We focus on luminous organisms that use the shared luciferin substrates coelenterazine or vargulin to produce light because these organisms convergently evolved bioluminescent proteins that use the same luciferins to produce bioluminescence. Evolutionary convergence does not necessarily extend across biological levels, as exemplified by cases of conservation and disparity in biological functions, organs, cells, and molecules associated with bioluminescence systems. Investigating differences across bioluminescent organisms will address fundamental questions on predictability and contingency in convergent evolution. Lastly, we highlight unexplored areas of bioluminescence research and advances in sequencing and chemical techniques useful for developing bioluminescence as a model system for studying multi‐level convergent evolution.
ARTICLE | doi:10.20944/preprints202012.0362.v1
Subject: Biology, Anatomy & Morphology Keywords: combined stresses; drought stress; heat stress; maize; root morphology; root types
Online: 15 December 2020 (09:39:56 CET)
Plants are continually exposed to multiple stresses, which co-occur in nature and the net effects are frequently more non-additive (i.e., synergistic or antagonistic) suggesting ‘unique’ responses respect to that of the individual stress. Further, plant stress responses are not uniforms showing a high spatial and temporal variability among and along the different organs. In this respect, the present work investigated the morphological responses of different root types (seminal, seminal lateral, primary, primary lateral) of maize plants exposed to single (drought and heat) and combined stress (drought + heat). Data were evaluated by a specific root image analysis system (WinRHIZO) and analyzed by uni- and multi-variate statistical analysis. The results indicated that primary root and their laterals were the types more sensitive to the single and combined stresses while the seminal laterals specifically responded to the combined only. Further, antagonistic and synergistic effects were observed for the specific traits in the primary and their laterals and in the seminal lateral roots in response to the combined stress. These results suggested that maize root system modified specific root types and traits to face with different stressful environmental conditions highlighting that the adaptation strategy to the combined stress may be different from that of the individual ones. The knowledge of “unique or shared” responses of plant to multiple stress can be utilized to develop varieties with broad spectrum stress tolerance.
Mon, 14 December 2020
ARTICLE | doi:10.20944/preprints202012.0351.v1
Subject: Biology, Anatomy & Morphology Keywords: Sesbania grandiflora; Tannins; Saponin; Methane; Fecal nitrogen; Ammonia; Propionate
Online: 14 December 2020 (15:45:19 CET)
The aim of the study was to evaluate the effect of crude protein (CP) levels in concentrate and Sesbania grandiflora pod meal (SG) supplementations on feed intake, rumen fermentation, and methane (CH4) mitigation in Thai purebred beef cattle. Four cattle with 100 ± 5.0 kg body weight were used in this study. A 2 × 2 factorial experiment in a 4 × 4 Latin square design were conducted, in which factor A was the CP contents in concentrate of 14, and 16% of dry matter (DM) and factor B was the supplement contents of SG at 0.4% and 0.6% DM intake, respectively. The results showed that the CP contents in concentrate and SG had no interaction effect on intake, digestibility, ruminal ecologies, ruminal fermentation products, and nitrogen utilization. Increasing CP contents in concentrate did not influence DM intake and nutrients’ digestibility, and SG supplementation at 0.6% significantly (P<0.05) decreased CP digestibility. Increasing CP content to 16% increased significantly (P<0.05) the ruminal ammonia nitrogen (NH3-N) concentration while decreased significantly (P<0.05) the NH3-N concentration, protozoal number, and blood urea nitrogen (BUN) at 4 h post-feeding. The 0.6% supplementation of the SG increased significantly average total volatile fatty acids (VFAs) and propionate (C3) concentration while decreased significantly average acetate (C2), C2:C3 ratio, and CH4 production, which was 2.71% for C2, 13.17% for C2:C3 ratio, and 4.37% for CH4 production lower than 0.4% supplementation. Fecal nitrogen excretion was significantly decreased when supplemented with 0.6% of the SG. In conclusion, 0.6% of the SG supplementation showed a greater effect on intake, rumen manipulation, and CH4 mitigation and would recommend supplementation to a concentrate-based diet containing either 14% or 16% CP content.
ARTICLE | doi:10.20944/preprints202012.0311.v1
Subject: Biology, Anatomy & Morphology Keywords: resource integration; network analysis; sustainability; small-scale farm
Online: 14 December 2020 (09:26:08 CET)
Shrinking farm size and fragile farm resources pose a significant challenge to the sustainability of small-scale farms. Efficient resource utilization in small-scale farms is crucial to achieving farm sustainability through endogenous mechanisms. However, the precise mechanisms to integrate physical resources to achieve farm sustainability are not very clear yet. By capturing the interaction among farm resources as a network phenomenon, we identify the discrete resource interactions (RIs) in different types of small-scale farms of Indian Sundarbans, which are associated with higher farm sustainability. Thirty-two linkages, 11 reciprocal linkages, 22 triads, and three ‘core elements’ that occurred and cooccurred on highly sustainable farms are found to be critical in achieving farm sustainability. Using the properties of resource interaction networks as explanators of farm sustainability, we anticipate that sustainability in small-scale farms can be achieved by strategically creating new RIs on the farm. However, there may be limitations to such achievement depending on the nature of RI and type of farm. The analytical approach helps to understand the structural basis of sustainability in small-scale farms, and this approach can be used to achieve farm sustainability through the strategic integration of existing farm resources in the smallholder systems.
REVIEW | doi:10.20944/preprints202012.0304.v1
Subject: Biology, Anatomy & Morphology Keywords: Vitrification; cooling; abiotic; biotic; stress; browning
Online: 14 December 2020 (08:17:26 CET)
Recent developments in the cryopreservation space has increased the trend in germplasm collections established through cryopreserved in vitro material. Cryopreservation of recalcitrant seeds through embryos and embryonic axes, is not uncommon. Tropical and sub-tropical plants are not acclimated to the cold season, therefore have no in-built natural resilience to the cold. Also, larger seeds from trees, such as avocado (Persea americana Mill.), mango (Mangifera indica) and durian (Durio zibethinus L.) are sensitive to desiccation, chilling and freezing stress, making them unsuitable for seed banking or cryopreservation. Alternatively, as seeds do not carry the same genetic make-up as the mother plant, especially in the context of woody rainforest species of which the cross-pollination is dominant; seed conservation does not serve the purpose of germplasm preservation. Other plant material and methods are needed for these plants to be successfully stored in liquid nitrogen (LN). One such method commonly used is shoot-tip cryopreservation which ensures the clonal fidelity of germplasm. There are many problems when using shoot tips of tropical recalcitrant-seeded species. These include: 1) the toxic effects of cryoprotective agents towards structural integrity; 2) optimum developmental stage for success and 3) oxidative stress associated with excision injury leading to necrosis triggering cell death and hindering regeneration for the shoot tips in culture. A pre-requisite for any cryopreservation system is the availability of an established tissue culture regeneration platform. This review will outline conservation strategies for avocado with special emphasis on attempts and improvements made in the cryopreservation space for storing this horticulturally important crop ‘avocado’ at ultra-low temperatures.
Fri, 11 December 2020
BRIEF REPORT | doi:10.20944/preprints202012.0283.v1
Subject: Biology, Anatomy & Morphology Keywords: SARS-CoV-2; Covid-19; wildlife; host-switching; reservoirs; risk assessment; surveillance
Online: 11 December 2020 (14:16:28 CET)
The novel coronavirus SARS-CoV-2 likely emerged from a wildlife source with transmission to humans followed by rapid geographic spread throughout the globe and dramatic impacts on both human health and global economies. Since the onset of the pandemic, there have been several instances of human-to-animal transmission involving companion, farmed and zoo animals, with the clear potential for spread into free-living wildlife. The establishment of reservoirs of infection in wild animals would create significant challenges to infection control in humans and could pose a threat to the welfare and conservation status of wildlife. Herein, we discuss the potential for exposure, maintenance and onward transmission of SARS-CoV-2 in an initial selection of wild and feral species (bats, canids, felids, mustelids, great apes). Targeted surveillance and dynamic risk assessment are important tools for the early detection of infection in wildlife and a means of collating and synthesising emerging information in a rapidly changing situation. Such efforts should be integrated with public health information to provide insights into the potential role of wild mammals in the continuing epidemiology of SARS-CoV-2. This approach should also be adopted to address the wider need to proactively assess threats to human and animal health from other diseases that may emerge from wildlife.
REVIEW | doi:10.20944/preprints202012.0274.v1
Subject: Biology, Anatomy & Morphology Keywords: seed dormancy; germination; light-mediated process; abiotic stress; epigenetic control; translational control
Online: 11 December 2020 (10:30:09 CET)
The transition from a dormant to a germinating seed represents a crucial developmental switch in the life cycle of a plant. Subsequent transition from a germinating seed to an autotrophic organism also requires a robust and multi-layered control. Seed germination and seedling growth are multistep processes, involving both internal and external signals, which lead to a fine-tuning control network.
COMMUNICATION | doi:10.20944/preprints202012.0271.v1
Subject: Biology, Anatomy & Morphology Keywords: osteoarthritis; African elephant; Asian elephant; captivity; mobility
Online: 11 December 2020 (08:49:07 CET)
The African bush and forest elephants, Loxodonta Africana and Loxodonta cyclotis, and the Asian elephant, Elephas maximus, are the largest land-dwelling animals. Elephants need to be highly mobile and active in order to find fresh food and water, and in the case of males, to locate females in estrus for breeding. Asian elephants walk up to 13 miles each day and African elephants can walk up to 28 km per day. This high level of mobility in the wild is also important for maintaining an optimum musculoskeletal health. However, their captive counterparts live in restricted spaces and cold climates that require extended periods of indoor confinement are therefore unable to be as physically active. Zoo enclosures for elephants are relatively small with hard surfaces (i.e. concrete, tarmac and hard packed dirt), so they cannot exercise and are forced to stand on unnaturally hard surfaces continually. Physical inactivity in captivity makes them more prone to gaining weight and developing bone and joint diseases such as osteomyelitis, joint ankylosis and osteoarthritis (OA). Up to 50% of deaths in captive elephants are caused by the lack of mobility. This perspective article focuses on the link between captivity, mobility, physical inactivity and the development of OA in captive elephants.
Thu, 10 December 2020
CONCEPT PAPER | doi:10.20944/preprints202012.0270.v1
Subject: Biology, Anatomy & Morphology Keywords: predation; spillover; transmission; disease ecology; cross-species transmission; pathogens; contact behavior; zoonotic disease
Online: 10 December 2020 (17:50:01 CET)
Predator-prey interactions present heightened opportunities for pathogen spillover, as predators are exposed to novel parasites through consumption of prey harboring potentially infectious agents. Epizootics with high morbidity and mortality have been recorded following prey-to-predator spillover events with significant conservation implications, particularly for sensitive species. However, relatively few virulent infections following prey consumption are reported, given the very large number of exposures that presumably occur. Further, many transmitted agents are infectious but clinically silent and thus go unrecognized. Mechanisms that determine outcome of predator exposure to prey-based pathogens therefore represent an important, understudied component of disease dynamics that should be considered in modeling approaches and empirical research to better understand disease risk and emergence, particularly in vulnerable or threatened species.
REVIEW | doi:10.20944/preprints202012.0244.v1
Subject: Biology, Anatomy & Morphology Keywords: CAMs; Classical Cadherins; Nectins; Neocortical Development; Radial Glia Cells; Neurons; Neuronal Migration; Axon Targeting; Synaptogenesis; Autism/Neurodevelopmental disorders
Online: 10 December 2020 (10:23:42 CET)
The neocortex is an exquisitely organized structure achieved through complex cellular processes from the generation of neural cells to their integration into cortical circuits after complex migration processes. During this long journey, neural cells need to stablish and release adhesive interactions through cell surface receptors known as cell adhesion molecules (CAMs). Several types of CAMs have been described regulating different aspects of neurodevelopment. Whereas some of them mediate interactions with the extracellular matrix, others allow contacts with additional cells. In this review, we will focus on the role of two important families of cell-cell adhesion molecules (C-CAMs), classical cadherins and nectins, as well as in their effectors, in the control of fundamental processes related with corticogenesis, with especial attention in the cooperative actions among the two families of C-CAMs.
Wed, 9 December 2020
ARTICLE | doi:10.20944/preprints202012.0224.v1
Subject: Biology, Anatomy & Morphology Keywords: PUI; careers in science; primarily undergraduate institution
Online: 9 December 2020 (12:15:53 CET)
Scientists who hope to obtain a faculty position at a primarily undergraduate institution (PUI) need a distinct skill set and outlook on their future teaching and research career. To obtain a position at a PUI, candidates should 1) design a strategy for obtaining a faculty position that suits each individual’s career goals and aspirations, 2) prepare for the application process, on-campus interview, and contract negotiations, and 3) plan a strategy for the probationary period leading up to tenure and promotion. Given the different types of PUIs, candidates need to consider whether they seek a position that consists of all or mostly all teaching, or both teaching and research. Candidates should educate themselves on the expectations at PUI’s, including current thought, practice, and aspirations for science pedagogy, and gain teaching experience prior to seeking a suitable position. If the candidate’s goal is a position with both teaching and research, it is important to discuss with the current research mentor what projects the candidate can take with them to their new position. The candidate should also consider what types of projects will be successful with undergraduate student researchers in a PUI research environment Importantly, candidates should clearly demonstrate a commitment to diversity and inclusion in their teaching, research, and outreach, and application materials should demonstrate this. On interviews, candidates should be knowledgeable about the mission, values, and resources of the institution and how the candidate will contribute to that mission. Once hired, new faculty should discuss a formal or informal mentoring plan during the probationary period that includes peer evaluations on a regular basis, and maintain communication with the department chair or designated mentor regarding teaching, research, and service activities.
REVIEW | doi:10.20944/preprints202012.0220.v1
Subject: Biology, Anatomy & Morphology Keywords: chromatography; amino acids; fatty acids; pork analysis; adipose tissue; muscle tissue; nutritional factors.
Online: 9 December 2020 (11:14:18 CET)
The increasing demand for high-quality livestock products dictates to develop approaches to assessing the composition of the fatty acids (CFAs) and amino acids (CAAs) in animal tissues. The review considers the following issues: chromatographic methods for the determination of CAAs and CFAs of pig tissues; factors influencing the CAAs and CFAs of pig tissues; methods of regulating CAAs and CFAs of pork using nutritional factors; the effect of CAAs and CFAs on formation of meat properties. The main methods for determining CAAs or CFAs are the ion-exchange or gas chromatography, respectively. The total FA amount and individual FAs have significant effects on the tenderness, taste, color and juiciness of pork meat (due to the different melting points of particular fatty acids, formation of lipid oxidation products during cooking, etc.). Muscle proteins of pigs with regulated fatness differ also in CAAs (decreasing by increase in “pork fat” and decrease in the protein’s amount. The significance of this review is also determined by high popularity of pork in Russia and in a number of other countries of the world.
HYPOTHESIS | doi:10.20944/preprints202010.0004.v6
Subject: Biology, Anatomy & Morphology Keywords: carbon-based entity; driving force; energy; evolution; fitness; mechanism; natural selection; speciation; thermodynamics; theory
Online: 9 December 2020 (11:01:03 CET)