ARTICLE | doi:10.20944/preprints202001.0383.v1
Subject: Earth Sciences, Environmental Sciences Keywords: bioretention; nitrogen removal; submerged zone; alternate wet and dry conditions
Online: 31 January 2020 (11:31:15 CET)
Adding a submerged zone (SZ) is deemed to promote denitrification during dry periods and thus improve NO3--N removal efficiency of a bioretention system. However, few studies had investigated the variation of nitrogen concentration in the SZ during dry periods and evaluated the effect of the variation on nitrogen removal of the bioretention system. Based on the experiment in a mesocosm bioretetion system with SZ, this study investigated the variation of nitrogen concentration of the system under 17 consecutive cycles of wet and dry alternation with varied rainfall amount, influent nitrogen concentration and antecedent dry periods (ADP). The results indicated that (1) during the dry periods, NH4+-N concentrations in SZ showed an exponential decline trend, decreasing by 50% in 12.9 ± 7.3 hours; while NO3--N concentrations showed an inverse S-shape decline trend, decreasing by 50% in 18.8 ± 6.4 hours; (2) during the wet periods, NO3--N concentration in the effluent showed an S-shape upward trend; and at the early stage of the wet periods, the concentration was relatively low and significantly correlated with ADP, while the corresponding volume of the effluent was significantly correlated with the SZ depth; (3) in the whole experiment, the contribution of nitrogen decrease in SZ during dry periods to NH4+-N and NO3--N removal accounted for 12% and 92%, respectively; and the decrease of NO3--N in SZ during the dry period was correlated with the influent concentration in the wet period and the length of the dry period.
ARTICLE | doi:10.20944/preprints201701.0014.v1
Subject: Earth Sciences, Environmental Sciences Keywords: rainwater; weather; windbreaker; cup anemometer; dry and wet bulb thermometers
Online: 4 January 2017 (07:27:41 CET)
Agro-meteorology is the relationship between agriculture and weather. All farm activities are affected by weather. Therefore it is always necessary to monitor the weather as a forecast. The aim of the research was to monitor the weather and rainwater samples obtained at Federal College of Agriculture, Akure, Ondo State, Nigeria. For the eight months periods, results were obtained. The mean results for the physicochemical parameters were: TDS (12.25 mg/L), temp (28.13 oC), pH (6.63), EC (24.25µS/cm), Free CO2 (24.38mg/L), nitrate (0.16mg/L), phosphate (0.17mg/L), sulphate (0.18mg/L). The rainwater was colorless and had no odor. The mean meteorological data: The prevailing wind directions were from SE, mostly in May, June, July and November and NE. The dry and wet temperatures were 22-29 oC and 20-26 oC respectively. The maximum value was observed in the month of July. The correlation matrix showed that there were many strong correlations in the physicochemical properties. The months of May, June and July had the highest wind speed. In these months there would be a need to use a windbreaker around the crops planted to avoid soil erosion and damaging of plants.
ARTICLE | doi:10.20944/preprints202203.0075.v1
Subject: Life Sciences, Biotechnology Keywords: Algae; wet anaerobic storage; dry matter loss; organic acid; lactic acid bacteria
Online: 4 March 2022 (08:45:40 CET)
Wet anaerobic storage of algal biomass is a promising preservation approach which can ensure continuous supply of these feedstocks to biorefineries year-round. An effective solution to preservation must ensure minimal dry matter loss and change in biochemical composition during storage. Therefore, the objective of this study was to investigate the preservation of Nannochloropsis gaditana biomass through wet anaerobic storage and its impact on biomass quality. Prior to storage, algae sample was inoculated with two different strains of lactic acid bacteria and thereafter stored for 30 and 180 days. Each inoculant limited dry matter loss to <10% (dry basis) after the storage durations. Final pH values (4.3 - 4.8) indicate that the biomass samples were properly ensiled, achieving the acidic conditions necessary for preservation. Compositional analysis of the biomass after storage showed a reduction in carbohydrate content, a relative increase in lipid content, and no significant change to the protein fraction. Glucose and galactose were the prevalent sugar monomers. The low dry matter loss and minimal compositional change indicates that wet anaerobic storage is an effective means of preserving algal biomass, ensuring a constant supply of algal biomass feedstock to a biorefinery.
Subject: Keywords: clay; mica; biotite; muscovite; origin of life; abiogenesis; mechanical energy; work; wet-dry
Online: 5 November 2020 (10:43:44 CET)
This paper presents a hypothesis about the origins of life in a clay mineral, starting with the earliest molecules, continuing through the increasing complexity of the development, in neighboring clay niches, of “Metabolism First,” “RNA World,” and other necessary components of life, to the encapsulation by membranes of the components in the niches, to the interaction and fusion of these membrane-bound protocells, resulting finally in a living cell, capable of reproduction and evolution. Biotite (black mica) in micaceous clay is the proposed site for this origin of life. Mechanical energy of moving biotite sheets provides one endless source of energy. Potassium ions between biotite sheets would be the source of the high intracellular potassium ion concentrations in all living cells.
ARTICLE | doi:10.20944/preprints202201.0022.v1
Subject: Life Sciences, Biophysics Keywords: clay; mica; biotite; muscovite; origin of life; abiogenesis; mechanical energy; work; wet-dry cycles
Online: 4 January 2022 (20:36:31 CET)
Intracellular potassium concentrations, [K+], are high in all types of living cells, but the origins of this K+ are unknown. The simplest hypothesis is that life emerged in an environment that was high in K+. One such environment is the spaces between the sheets of the clay mineral, mica. The best mica for life’s origins is the black mica, biotite, because it has a high content of Mg++ and it has iron in various oxidation states. Life also has many of the characteristics of the environment between mica sheets, giving further support for the possibility that mica was the substrate on and within which life emerged.
ARTICLE | doi:10.20944/preprints201904.0297.v1
Subject: Chemistry, Other Keywords: hyperbranched polyester; functional polymer; chemical evolution; wet-dry cycle; gelation prevention; condensation polymer; origin of life
Online: 26 April 2019 (10:46:40 CEST)
In extant biology, biopolymers perform multiple crucial functions. The biopolymers are synthesized by enzyme-controlled biosystems that would not have been available at the earliest stages of chemical evolution and consist of correctly sequenced and/or linked monomers. Some of the abiotic “messy” polymers approximate some functions of biopolymers. Condensation polymers are an attractive search target for abiotic functional polymers since principal polymers of life are produced by condensation and since condensation allows for the accurate construction of high polymers. Herein the formation of hyperbranched polyesters that have been previously used in the construction of enzyme-like catalytic complexes is explored. The experimental setup compares between the branched polyesters prepared under mild continuous heating and the wet-dry cycle conditions. The results reveal that period wetting during which partial hydrolysis of the polyester occurs, helps control the chain growth and retards the gel transition. It is significant to the origin of life studies that environmental, prebiotically plausible conditions could achieve such control without enzymes or a skilled chemist. As expected in marginally controlled systems, the identification of each component of the heterogeneous system has proved challenging, but it is not crucial for drawing the conclusions.
Subject: Life Sciences, Molecular Biology Keywords: origin of life; origins of life; mechanical energy; work; entropic forces; mica; biotite; Muscovite; wet/dry cycles; clay
Online: 29 April 2019 (07:51:38 CEST)
Forces and mechanical energy are prevalent in living cells. This may be because forces and mechanical energy preceded chemical energy at life’s origins. Mechanical energy is more readily available in non-living systems than the various other forms of energy used by living systems. Two possible prebiotic environments that might have provided mechanical energy are hot pools that experience wet/dry cycles and mica sheets as they move, open and shut, as heat pumps or in response to water movements.
ESSAY | doi:10.3390/sci2020019
Subject: Keywords: origin of life; origins of life; mechanical energy; mechanochemistry; work; entropic forces; mica; biotite; Muscovite; wet/dry cycles; clay
Online: 25 March 2020 (00:00:00 CET)
Mechanical forces and mechanical energy are prevalent in living cells. This may be because mechanical forces and mechanical energy preceded chemical energy at life’s origins. Mechanical energy is more readily available in non-living systems than the various forms of chemical energy used by living systems. Two possible prebiotic environments that might have provided mechanical energy are hot pools that experience wet/dry cycles and mica sheets as they move, open and shut, as heat pumps or in response to water movements.
REVIEW | doi:10.20944/preprints202103.0555.v1
Subject: Engineering, Automotive Engineering Keywords: dry EEG; dry EEG electrode; dry electrode; electroencephalography; non-contact electrode EEG
Online: 23 March 2021 (08:56:57 CET)
The basis of the work of electroencephalography (EEG) is the registration of electrical impulses from the brain or some of its individual areas using a special sensor/electrode. This method is used for the treatment and diagnosis of various diseases. The use of wet electrodes in this case does not seem viable, for several well-known reasons. As a result of this, a detailed analysis of modern EEG sensors developed over the past few years is carried out, which will allow researchers to choose this type of sensor more carefully and, as a result, conduct their research more competently. Due to the absence of any standards in the production and testing of dry EEG sensors, the main moment of this manuscript is a detailed description of the necessary steps for testing a dry electrode, which will allow researchers to maximize the potential of the sensor in the various type of research.
ARTICLE | doi:10.20944/preprints202210.0354.v1
Online: 24 October 2022 (07:14:38 CEST)
Spider silk has excellent strength and elasticity in natural, researchers have been working for decades try to achieve natural spider silk outstanding mechanical properties using recombinant spider silk protein (spidroin) through artificial spinning. In this work, we chose wet spinning method to explore the relationship between concentration of coagulation bath and fiber performance. It was found that the concentration of methanol has important effect on fiber continuity, diameter and mechanical properties. Lower concentration favors spinning continuous thinner, fibers with high strain. Secondary stretching benefits spinning silk fibers with stable mechanical properties, and thermal stability. Through applying different methanol concentration and additional stretching, we obtained silk fibers with Young’s modulus of 3.052± 2.626 GPa, stress of 25.3944 ± 17.48 MPa, and strain of 140 ± 95.4%.
ARTICLE | doi:10.20944/preprints201805.0420.v1
Subject: Engineering, General Engineering Keywords: wet agglomeration; flocculation; hydrodynamics; turbulence
Online: 29 May 2018 (09:00:36 CEST)
In this study, an experimentally validated computational model was developed to investigate the hydrodynamics in a rotor-stator vortex RVR agglomeration reactor having a rotating disc at the centre with two shrouded outer plates. A numerical simulation was performed using a simplified form of the reactor geometry to compute the 3D flow field in batch mode operations. Thereafter, the model was validated using data from a 2D Particle Image Velocimetry (PIV) flow analysis performed during the design of the reactor. Using different operating speeds—70, 90, 110 and 130 rpm, the flow fields were computed numerically followed by a comprehensive data analysis. The simulation results showed separated boundary layers on the rotating disc and the stator. The flow field within the reactor is characterized by a rotational plane circular forced vortex flow in which the streamlines are concentric circles with a rotational vortex. Overall, the results of the numerical simulation demonstrate a fairly good agreement between the CFD model and the experimental data as well as the available theoretical predictions. The swirl ratio β was found to be approximately 0.4044, 0.4038, 0.4044 and 0.4043 for operating speeds of N=70, 90, 110 and 130 rpm respectively. In terms of the spatial distribution, the turbulence intensity and kinetic energy are concentrated on the outer region of the reactor while the axial velocity showed a decreasing intensity towards the shroud. However, a comparison of the CFD and experimental predictions of the tangential velocity and the vorticity amplitude profiles shows that these parameters were under-predicted by the experimental analysis which could be attributed to some of the experimental limitations rather than the robustness of the CFD model or numerical code.
ARTICLE | doi:10.20944/preprints202102.0450.v1
Subject: Materials Science, Biomaterials Keywords: Wet spinning; Lanthanum oxide; Biochar; Chromate; Adsorption
Online: 22 February 2021 (08:51:53 CET)
Lanthanum chemical compound incorporates a sensible anionic complexing ability, however lacks stability at low pH scale. Biochar fibers will benefit of their massive space and plethoric useful teams on surface to support metal chemical compound. Herein, wet spinning technology was used to load La3+ onto sodium alginate fiber, and convert La3+ into La2O3 through carbonization. The La2O3 modified biochar (La-BC) fiber was characterized by SEM, XRD and XPS, etc. The adsorption experiment proved that La-BC showed excellent adsorption capacity for chromates, and its saturation adsorption capacity was about 104.93mg/g. The information suggested that the adsorption was in step with both Langmuir and Freundlich model, followed pseudo-second-order surface assimilation mechanics, which instructed that the Cr (VI) adsorption was characterized by single-phase and polyphase adsorption, mainly chemical adsorption. Thermodynamic parameter proved that the adsorption process was spontaneous and endothermic. The mechanistic investigation revealed that the mechanism of adsorption of Cr (VI) by La-BC may include electrostatic interaction, ligand exchange or complexation. Moreover, co-existing anions and regeneration experiments proved that La-BC was recyclable and had a good prospect in the field of chrome-containing wastewater removal.
ARTICLE | doi:10.20944/preprints202211.0446.v1
Subject: Medicine & Pharmacology, Sport Sciences & Therapy Keywords: Ultrasound; Physiotherapy; Rehabilitation; Dry Needling
Online: 23 November 2022 (12:34:09 CET)
Ultrasound is a well-known tool to produce thermal and non-thermal effects on cells and tissues. These effects require a correct application of ultrasound in terms of localization and acoustic energy delivered. This article describes a new device that combines ultrasound and Dry Needling treatments. The ultrasound transducer can rotate in 3D space mechanically to align itself in the direction of the needle. The transducer electronically focuses the acoustic pressure automatically on the needle tip and its surroundings. A computer, using graphical interface software, controls the angulation of the array and the focus position.
ARTICLE | doi:10.20944/preprints201702.0081.v1
Subject: Earth Sciences, Atmospheric Science Keywords: reference evapotranspiration; climatic change; drought/wet; Songnen Grassland
Online: 22 February 2017 (16:46:01 CET)
Reference evapotranspiration (ET0) plays an irreplaceable role in regional dry/wet conditions under the background of climate change. Based on the FAO Penman-Monteith method and daily climate variables, ET0 was calculated for 22 stations in and around Songnen Grassland, northeast China, during 1960-2014. The temporal and spatial variations of ET0 and precipitation (P) were comprehensively analyzed at different time scales by using the Mann-Kendall test, Sen’s slope estimator, and linear regression coupling with break trend analysis. Sensitivity analysis was used to detect the key climate parameter attributed to ET0 change. Then, the role of ET0 in regional dry/wet conditions was discussed by analyzing the relationship between ET0, P and aridity index (AI). Results shown a higher ET0 in the southwest and a lower in the northeast, but P was opposite to that of ET0. Evidently decreasing trend of ET0 at different time scales was detected in almost the entire region, and the significant trend mainly distributed in the eastern, northeastern and central. For the whole region, sensitivity analysis indicated decreasing trend of ET0 was primarily attributed to relative humidity and maximum air temperature. The positive contribution of increasing temperature rising to ET0 was offset by the effect of significantly decreasing relative humidity, wind speed and sunshine duration. In addition, the value of ET0 shown higher in drought years and lower in wet years.
Subject: Medicine & Pharmacology, Other Keywords: Xerostomia; Dry mouth; Salivary hypofunction; Saliva
Online: 22 July 2020 (09:44:12 CEST)
Xerostomia is a subjective symptom of dry mouth resulting from various causes, including side effects of medication, systemic disorders, radiation, and Sjögren’s syndrome. Recently, the number of patients afflicted with xerostomia has increased due to an increase in the elderly population and patients on medication.; (2) Methods: A systematic approach is required to determine the etiology and management of xerostomia. This review summarizes recent literatures on the diagnosis and management of xerostomia.; (3) Results: A patient with xerostomia experiences difficulty in chewing, swallowing, speaking, tasting, and maintaining oral hygiene. Xerostomia and hyposalivation are uncomfortable side-effects in many patients. Assessing the function of the salivary gland is essential for selecting an appropriate treatment, improving symptoms, and preventing oral complications. Also, a more systematic approach is required to differentiate the subjective symptoms of the patient from the objective hyposalivation.; and (4) Conclusions: Although there is no standardized treatment for xerostomia, doctors need to endeavor and adapt the various treatments of xerostomia, to unearth the optimal treatment required for the patient.
Subject: Engineering, Automotive Engineering Keywords: Window Performance; Cold Air Film; U-Value; Wet hey
Online: 25 May 2021 (11:51:48 CEST)
The concept of this prototype is to create a cold air film layer, in indoor side of the window. The function of this extra cold air layer is to increase the amount of window resistance and decrease its U-Value. It provide air film layer by using the same concept of desert cooler or wind catcher. They both bring the hot air from outside then let it go throw straw miost with cold water. After hot air move through straw, it would become cold, thus increase the window resistance and decrease the haet gian, therefore, decrease the cooling load. So, this window model works by heating the air in air room by sun radiation, then after a while, air pressure will rise and its volume will increase then it will impulse to wet hay, and become cold. Then there is fins to guide air flow to its correct direction, thus inner side of window will become cold, not like other type of window which when temperature rise, the inner side of window become hot. So, this window prevents heat transition and creare regenereted trubouland air flim in the inner side of the window. Using calculation to find air film characteristics and WINDOW7.7 software to calculate heat gain through window, shows that it is expected from this prototype to reduce heat gain by 6.85 % for double glazed clear window.
ARTICLE | doi:10.20944/preprints202101.0333.v2
Subject: Chemistry, Applied Chemistry Keywords: Wet chemical deposition; crystalline thin films; vanadium dioxide; thermochromism
Online: 17 February 2021 (10:38:44 CET)
In this paper, a novel synthesis for a chemical precursor for nanocrystalline VO2 coatings is elaborated. The compatibility of the precursor towards the substrate is optimized for spin coating. This is done by subjecting multiple solvents to contact angle measurements. A suitable thermal treatment is developed to densify the coating and to induce crystallization. Afterwards the microstructure of the coating is investigated using X-Ray diffraction, electron microscopy and ellipsometry techniques. To assess the thermochromic properties of the fabricated device, optical transmission experiments were conducted both at room temperature and at elevated temperature. A correlation between these thermochromic properties and coating thickness was investigated in order to obtain an optimized thermochromic device, where both high visual transparency and prominent thermochromic switching abilities are aimed for. In this work, an optimal coating thickness is proposed for a thermochromic coating with high switching ability and solar modulation.
ARTICLE | doi:10.20944/preprints202110.0240.v2
Subject: Materials Science, General Materials Science Keywords: graphene; dry ice; mechanical milling; magnesium oxide
Online: 13 January 2022 (13:44:03 CET)
Although the dry ice method used to synthesize exfoliated graphite/graphene is little known and used, it has significant advantages over others: it is low cost, simple, and a large quantity of material can be obtained using some inorganic and highly available acids (which can be reused). Despite the above advantages, the main reason for its incipient development is the resulting presence of magnesium oxide in the final product. In the present work, three different treat-ments were tested to remove this remnant using some acid chemical leaching processes, making use of hydrochloric acid, aqua regia, and piranha solution. Based on the experimental evidence, it was found that using aqua regia and combining the leaching process with mechanical milling was the most efficient way of removing such a remnant, the residue being only 0.9 wt.%. This value is low when compared to that obtained with the other acid leaching solutions and purifi-cation process (2.8 - 29.6 wt.%). A mandatory high-energy mechanical milling stage was neces-sary during this treatment, in order to expose and dissolve the highly insoluble oxide without secondary chemical reactions on the graphenes. High-energy mechanical milling is an effective route to exfoliate graphite/graphene, which allows the magnesium oxide to be more susceptible to acid treatment. The obtained surface area was 504 m2g-1; this high value resulting from the in-tense exfoliation can potentiate the use of this material for a wide variety of applications.
ARTICLE | doi:10.20944/preprints202102.0254.v1
Subject: Biology, Anatomy & Morphology Keywords: Chemical composition; Dry matter digestibility; Gas test
Online: 10 February 2021 (12:32:21 CET)
This investigation was conducted to determine the chemical composition and nutritional value of five plant species commonly used as ruminant feeds namely: Artemisia herba-alba, Acer monspessulanum, Amygdalus lycoides, Amygdalus scoparia, and Atriplex leucoclada. After the collecting samples, the chemical compositions of plants included dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), ash (CA), cell wall (NDF), and non-lignin cell wall (ADF) were determined according to standard methods. For degradation testing, the nylon bag technique was applied using three native Sistani fistula calves. Organic matter digestibility (OMD) and metabolisable energy (ME) were determined through the gas production technique. The CP value ranged from 5.30 (Amygdalus scoparia) to 11.72% (Atriplex leucoclada) while NDF value ranged from 52.62 (Amygdalus lycoides) to 69.05% (Amygdalus scoparia). The range of OMD, DOMD, and ME was from 36.67 to 53.27%, 34.67 to 49.11%, and 5.57 to 8.08 (MJ/kg), respectively. The results showed a positive correlation between cell wall composition and dry matter digestibility in plant species. The nutritional value of Amygdalus lycoides, Atriplex leucoclada, Acer monspessulanum, and Artemisia herba-alba was acceptable composition and digestibility.
ARTICLE | doi:10.20944/preprints202011.0271.v1
Online: 9 November 2020 (10:13:21 CET)
The experiment was conducted in three locations Jari, Chefa and Sirinka of Eastern Amhara to select the best performing varieties, in terms of biomass yield, chemical composition, haulm yield, seed yield and other agronomic characteristics of Glycine max (L.) Merrill grown under the rain- fed condition of lowland areas of Eastern Amhara in a randomized complete block design with tree replications. Twelve released soybean varieties were Afgat ,Belesa-95, Boshe , Cheri , Dhidhessa, Gishama , Gizo, Korme, Pawe-03, katta, Wegayen and Wollo were used as a treatments. The seeds were planted in 40 cm between rows and 10 cm between plants on a plot size of 3.2m*4m. Spacing between blocks and plots were 1 and 0.5m, respectively. The seed rate was 60 kg/ha and a fertilizer rate 100 kg/ha NPS was applied during seed planting. The combined analysis of variance over two years at location Jari for dry matter yield of varieties Afgat, Gizo, Pawe-03, Wogayen and Wollo were significantly higher as compared to other soybean varieties. The combined analysis across locations at Jari and Sirinka (2019-second year) showed that varieties Afgat, Gishama, Gizo, Pawe-03, Wogayen and Wollo had higher dry matter yield and varieties Gishama (3.97 t/ha), Gizo (3.60 t/ha), Pawe-03 (4.04 t/ha) and Wogayen (3.36 t/ha) had higher haulm yield as compared with other varieties. The combined analysis across locations at Jari and Sirinka (2019) showed that varieties Pawe-03(2951 kg/ha), Gizo (2862 kg/ha), Afgat (2859 kg/ha), Gishama (2654 kg/ha),Wollo (2461 kg/ha) and Wogayen (2404 kg/ha) had higher seed yield as compared with other varieties. The variety Wollo gave higher crud protein content in two locations (Jari and Sirinka) .Therefore, varieties Afgat, Pawe-03 and Wollo were recommends for the given areas of Jari , Chefa, Sirinka and could be produced in similar environments for the best of produced optimal amount of dry matter, haulm and seed yield and good protein supplement for production of ruminants.Thus, further researches will be needed to investigate on the utilization of livestock.
ARTICLE | doi:10.20944/preprints201812.0215.v1
Online: 18 December 2018 (10:19:37 CET)
This study investigated dry reforming of methane with combined catalysts supported on γ-Al2O3 support doped with 3.0 wt. % TiO2. The physicochemical properties of all the catalysts were determined by inductively-coupled plasma/mass spectrometry metal analysis, nitrogen physisorption, X-ray diffraction, temperature programmed reduction/desorption, thermogravimetric analysis, and scanning electron microscopy. The addition of CeO2 and MgO to Ni strengthened the interaction between the Ni and the support. The catalytic activity results indicated that the CeO2 and MgO addition to Ni did not do much in retarding carbon deposition, but they improved the activity of the catalysts. Among the tested catalysts, it was found that the catalyst with the composition of 5.0 wt % NiO-10.0 wt % CeO2/3.0 wt %TiO2-γ-Al2O3 resulted in the highest CH4 and CO2 conversion with H2/CO mole ratio close to unity. The optimum reaction conditions in terms of reactant conversion and H2/CO mole ratio were achieved by varying space velocity and CO2/CH4 mole ratio.
ARTICLE | doi:10.20944/preprints201607.0081.v1
Subject: Earth Sciences, Environmental Sciences Keywords: resilience, land management, wildfire, Mediterranean dry forest
Online: 27 July 2016 (10:01:44 CEST)
Wildfires have always been a part of the history of Mediterranean forests. However, forest regeneration after a wildfire is not certain. It depends on many factors, some of which may be influenced by land management activities. Failure of regeneration will cause a regime shift in the ecosystem, reducing the provision of ecosystem services and ultimately leading to desertification. How can we increase Mediterranean forests’ resilience to fire? To answer this question, we did a literature review, investigating chains of processes that allow forests to regenerate (which we label “regeneration mechanisms”), and assessed the impact of selected management practices documented in the WOCAT database on the regeneration mechanisms. We identified three distinct regeneration mechanisms that enable Mediterranean forests to recover, as well as the time frame before and after a fire in which they are at work, and factors that can hinder or support resilience. The three regeneration mechanisms enabling a forest to regenerate after a fire consist of regeneration (1) from a seed bank; (2) from resprouting individuals; and (3) from unburned plants that escaped the fire. Management practices were grouped into four categories: (1) fuel breaks, (2) fuel management, (3) afforestation, and (4) mulching. We assessed how and under what conditions land management modifies the ecosystem’s resilience. The results show that land management influences resilience by interacting with resilience mechanisms before and after the fire, and not just by modifying the fire regime. Our analysis demonstrates a need for adaptive – i.e. context- and time-specific – management strategies.
ARTICLE | doi:10.20944/preprints202002.0075.v2
Subject: Mathematics & Computer Science, Algebra & Number Theory Keywords: wet-bulb depression; relative humidity; ANFIS; artificial neural network; LSSVM
Online: 2 November 2020 (09:44:25 CET)
The main parameters for calculation of relative humidity are the wet-bulb depression and dry bulb temperature. In this work, easy-to-used predictive tools based on statistical learning concepts, i.e., the Adaptive Network-Based Fuzzy Inference System (ANFIS) and Least Square Support Vector Machine (LSSVM) are developed for calculating relative humidity in terms of wet bulb depression and dry bulb temperature. To evaluate the aforementioned models, some statistical analyses have been done between the actual and estimated data points. Results obtained from the present models showed their capabilities to calculate relative humidity for divers values of dry bulb temperatures and also wet-bulb depression. The obtained values of MSE and MRE were 0.132 and 0.931, 0.193 and 1.291 for the LSSVM and ANFIS approaches respectively. These developed tools are user-friend and can be of massive value for scientists especially, those dealing with air conditioning and wet cooling towers systems to have a noble check of the relative humidity in terms of wet bulb depression and dry bulb temperatures.
ARTICLE | doi:10.20944/preprints201911.0128.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: ditches; grain yield; lodging resistance; root traits; wet-seeded rice
Online: 12 November 2019 (10:25:04 CET)
The mechanical hill wet-seeded rice machine is benefits to establish uniform seedling, and ditches were established by using this machine. However, little knowledge is known on the effect of the establishment of ditches on growth, lodging and yield, and their relationship with root traits. In this study, two field experiments were conducted during 2012 and 2013 with using two super rice varieties (i.e. hybrid rice ‘Peizataifeng’ and inbred rice ‘Yuxiangyouzhan’) grown under three ditches establishment treatments (i.e. T1: both water ditches and seed ditches were established by the machine, T2: seed ditches were established by the machine, T3: neither water nor seed ditches were established by the machine). The lodging index and lodging resistance traits, the grain yield and above-ground dry weight and the root traits were measured. The results showed that the lodging index was significantly affected by the treatments with ditches. The strongest lodging resistance was detected in mechanical hill wet-seeded rice with ditches treatment in both 2012 and 2013. The lodging resistance was strongly related to the breaking resistance, the root volume and root superficial area at the heading stage and maturity stage and the total root length at the heading stage. No significant difference was investigated in grain yield or dry weight of mechanical hill wet-seeded rice. Yuxiangyouzhan showed higher grain yield, dry weight and better lodging resistance but unfavorable root growth attributes than Peizataifeng. Therefore, the mechanical hill wet-seeded rice with ditches treatment increased rice lodging resistance is related to root traits.
ARTICLE | doi:10.20944/preprints202211.0044.v1
Subject: Mathematics & Computer Science, General & Theoretical Computer Science Keywords: Dry eye disease; Artificial Intelligence; diagnosis; bibliographic study
Online: 2 November 2022 (04:21:40 CET)
Dry eye disease (DED) is one of the most common eye diseases. There is at least one DED patient in almost every five people. AI-based research methods increasingly become the focus of DED diagnosis research. This study utilizes a systematic review method on DED AI-based diagnosis. 2112 unduplicated records are extracted from Google Scholar, Web of Science (WOS), PubMed, China National Knowledge Infrastructure (CNKI), and Scopus databases. The most contributed countries, institutions, authors, journals, references, and disciplines are recognized. Keyword distribution and hot topics are identified. Popular databases of ophthalmic images, videos, and electronic demographic medical records are discussed. The DED diagnosis, classification, and grading criteria are identified. The major diagnosing methods are clustered, compared, and investigated. Findings show that diagnosing method research could be classified into three categories based on the relationship between AI techniques, which are (1) ground truth and/or comparable standards for AI DED diagnosis (TBUT, S Ⅰ T, TMH, and OSDI), (2) potential methods for AI-based methods have a great advantage(DED detection based on meibometry Images, CASPs, IVCM Images, OCT Images, blink videos and ultrasonic imaging), (3) and the potential direction and supplemented methods for AI-based DED detection (DED detections based on tear osmolarity, proteomic analysis, TCM and demographic information). AI-based approaches based on digital ophthalmologic images play an important role in early screening. Challenges and future perspectives are discussed at the end of this article, academically and practically.
ARTICLE | doi:10.20944/preprints201609.0061.v1
Subject: Earth Sciences, Atmospheric Science Keywords: dry intrusion; Stratosphere-troposphere exchange; mid-latitude; satellite
Online: 18 September 2016 (10:27:56 CEST)
Dry intrusion is an important mid-latitude atmosphere phenomenon within the upper troposphere and lower stratosphere. It is always found to be related to the cyclogenesis, rainstorm, as well as convection generation and precipitation enhancement. Since the atmosphere environment for any of these above-mentioned weather is terribly complicated, those preexisting popular schemes which takes no account of water vapor may not suitable for detecting the dry intrusion related to these weathers. With regard to the merits and demerits of the current preexisting schemes, a new scheme based on Fengyun-2E geo-stationary satellite data is presented in this study to detect the atmospheric dry intrusion. The scheme is set up based on the statistical relationship between water vapor at high level troposphere, the general moist potential vorticity, ozone concentration and upper-level jet. After using the total amount of ozone and ozone profile operational products retrieved by Fengyun-3 Polar Orbiting Meteorological Satellites and the potential vorticity calculated by ECMWF Interim data for validation, this scheme is applied to analyze two typical middle-latitude weather processes. One is the famous Beijing extreme rainfall of 21 July 2012 and the other is a hailstorm occurred on the eastern China during March 19, 2014. A good application effect in both cases suggests that our new method of detecting dry intrusion is feasible and can be helpful in middle-latitude disastrous weather monitoring and forecasting.
ARTICLE | doi:10.20944/preprints202205.0237.v1
Subject: Medicine & Pharmacology, Ophthalmology Keywords: dry eye; intense pulsed light therapy; meibomian gland; tear
Online: 18 May 2022 (06:14:55 CEST)
Dry eye disease (DED) most commonly caused by evaporative subtypes and mainly induced by meibomian gland dysfunction (MGD). Intense pulsed light (IPL) combined with meibomian gland expression (MGX) is noninvasive treatment for improvement of ocular discomfort symptoms and MGD. In this prospective study between November 2020 and May 2022, the patients met the criteria of both ocular surface disease index (OSDI) ≥13 scores and standardized patient evaluation of eye dryness (SPEED)≥ 8 scores were enrolled in Kaohsiung Veteran General Hospital. Three separate treatment sessions of IPL therapy combined with MGX administered to the lower lids with an interval of 28 days. Further tear film assessment included lipid layer thickness (LLT), tear meniscus height (TMH), non-invasive tear break-up time (NIBUT), meibomian gland loss (MGL) either beforeor after 1st and 3rd IPL therapy combined with MGX. Besides, lissamine green staining and pain scores were also recorded. We totally enrolled 37 patients of 74 eyes. Men accounted for 18.92% (7/37). The mean age was 54.51 ± 11.72 years. The mean OSDI scores were 58.12 ± 22, while the SPEED scores were 17.03 ± 5.98. The mean Schirmer’s test was 3.66 ± 2.43 mm. After three sessions IPL treatment with MGX, the OSDI, SPEED, LLT, TMH, MGL, MGXS and pain scores were significantly improved. For the MGX scores (MGXS) ≤20 group, MGL and lissamine green scores showed significant improvements. For the MGXS >20 group, TMH and dry spot rate revealed statistically improvement. Noninvasive IPL therapy with MGX statistically improved not only dry eye symptoms but also tear film assessments.
ARTICLE | doi:10.20944/preprints202203.0255.v1
Subject: Materials Science, Surfaces, Coatings & Films Keywords: spray dry; protein; encapsulation; formulation; excipient; core-shell; EISA
Online: 17 March 2022 (12:19:43 CET)
The encapsulation of proteins into core-shell structures is a widely utilised strategy for controlling protein stability, delivery and release. Despite the recognised utility of these microstructures, however, core-shell fabrication routes are often too costly or poorly scalable to allow for industrial translation. Furthermore, many scalable routes rely upon emulsion-techniques implicating denaturing or environmentally harmful organic solvents. Herein, we investigate core-shell protein encapsulation through single-feed, aqueous spray drying: a cheap, industrially ubiquitous particle-formation technology in the absence of organic solvents. We show that an excipient’s preference for the surface of the spray dried particle is well-predicted by its hydrodynamic diameter (Dh) under relevant feed buffer conditions (pH and ionic strength) and that the predictive power of Dh is improved when measured at the spray dryer outlet temperature compared to room temperature (R2 = 0.64 vs. 0.59). Lastly, we leverage these findings to propose an adaptable design framework for fabricating core-shell protein encapsulates by single-feed aqueous spray drying.
ARTICLE | doi:10.20944/preprints202201.0175.v1
Subject: Physical Sciences, Applied Physics Keywords: Parametric excitation; Dry-Friction; Magnetic Spring Force; Electronic circuit
Online: 12 January 2022 (14:33:34 CET)
In this paper, we have shown the electronic circuit equivalence of a mechanical system consists of two oscillators coupled with each other. The mechanical design has the effects of the magnetic, resistance forces and the spring constant of the system is periodically varying. We have shown that the system’s state variables, such as the displacements and the velocities, under the effects of different forces, lead to some nonlinear behaviors, like a transition from the fixed point attractor to the chaotic attractor through the periodic and quasi-periodic attractors. We have constructed the equivalent electronic circuit of this mechanical system and have verified the numerically obtained behaviors using the electronic circuit.
ARTICLE | doi:10.20944/preprints202111.0465.v1
Subject: Engineering, Civil Engineering Keywords: Cement Concrete Pavement; Concrete behavior; Dry shrinkage; Autogenous shrinkage
Online: 25 November 2021 (09:08:48 CET)
(1)Background: Early-age concrete shrinkage induces stress that impact the cost and service life of concrete pavements. (2)Methods: In this study, strain measurements of field slabs were conducted and a methodology was presented that independently derived autogenous, drying, and thermal shrinkages in the initial stages of concrete placement. Total strain was measured according to five different environmental conditions and shrinkage strain was calculated for each condition. (3)Results: By measuring the strain of the slab and the specimen, the drying shrinkage strain was measured to be approximately 54% better than that by the conventional non-stressed cylinder method because it was possible to measure the drying shrinkage strain at the surface rather than in the middle part of the slab along its depth direction. When the water-to-cement ratio increased (35→40%), there was a considerable reduction (317με→82με) of autogenous shrinkage strain for the concrete at 28 days of age. Furthermore, calculation of stress-dependent strain allowed the presentation of more intuitive and accurate results. (4)Conclusion: As the measurement of independent shrinkage occurrence is possible, the consequent calculated result of the stress-dependent strain acting on real slabs will facilitate improvement in the construction quality, reduction in the development of defects in the concrete structure, and increase in the service life.
ARTICLE | doi:10.20944/preprints202111.0363.v1
Subject: Life Sciences, Biochemistry Keywords: leguminous root crop; high quality protein; dry matter yield
Online: 19 November 2021 (14:45:52 CET)
Among the many neglected underutilized species, tuberous Andean root crops like the ahipas (Pachyrhizus ahipa) constitute a promising alternative for increasing diversity in nutrient sources and food security at a regional level. In this study, we present the content of some functional compounds in tuberous roots from several ahipa accessions and the progenies of the interspecific hybrid X207 (P. ahipa × P. tuberosus). A significant objective was to determine protein and free amino acids in the roots to evaluate their food quality as protein supply. The interspecific hybrids have been found to possess the root quality to provide the crop with a higher dry matter content. The high dry matter content of the P. tuberosus Chuin materials is retained in the root quality of the hybrids. Food functional components like carbohydrates, organic acids, and proteins were determined in several ahipa accessions and a stable (non-segregating) progeny of the interspecific hybrid, X207. The X207 roots showed a significantly higher dry matter content and a lower content in soluble sugars, but no significant differences were found in starch content or organic acids compared to the ahipa accessions. About the root mineral contents, Fe and Mn concentrations in X207 were significantly raised compared to the average of ahipa accessions. Among the ahipa and the hybrid, no prominent differences in protein content or protein amino acids were found, being both partially defective in providing sufficient daily intake of some essential amino acids. Root weight, a central component of root yield, was significantly higher in X207, but thorough field studies are required to substantiate the hybrid’s superior yield performance..
ARTICLE | doi:10.20944/preprints201810.0555.v1
Subject: Biology, Ecology Keywords: alternative states; secondary succession; tropical dry forest; Pteridium aquilinum
Online: 24 October 2018 (07:48:46 CEST)
Understanding the role of invasive species in ecosystem functioning represents one of the main challenges in ecology. Pteridium aquilinum is a successful cosmopolitan invasive species with negative effects on the ecological mechanisms that allow secondary succession. In this study we evaluated whether P. aquilinum favours the establishment of alternative states, as well as the effect of recovery strategies on the secondary succession. A random stratified sampling was established with three treatments, each one with at least 50 year of fern invasion and with variations on the periodicity of fires and cuttings (chapeos) vs one control without fern bracken We determined the species richness and composition, as well as the relative importance value (IVI) in each treatment. We found that P. aquilinum decreases the action of the mechanisms that allow secondary succession, particularly facilitation. The recovery strategies consist in monthly cuttings and control fires allow to recover the secondary succession and eventually, the regeneration of areas invaded by P. aquilinum. Our study has relevant implications on the ecology of alternative state, and in practical strategies to maintain tropical forests, as well as for the maintenance of environmental services and sustainability.
REVIEW | doi:10.20944/preprints202108.0134.v1
Subject: Materials Science, Biomaterials Keywords: Methylcellulose; cellulose nanocrystal; hydrogel; birefringence; wet-spinning; optical fiber; thermoresponsive; LCST; nanocomposite
Online: 5 August 2021 (10:15:49 CEST)
Chemical modification of cellulose offers routes for structurally and functionally diverse biopolymer derivatives for numerous industrial applications. Among cellulose derivatives, cellulose ethers have found extensive use, such as emulsifiers, in food industries and biotechnology. Methylcellulose, one of the simplest cellulose derivatives, has been utilized for biomedical, construction materials and cell culture applications. Its improved water solubility, thermoresponsive gelation, and the ability to act as a matrix for various dopants also offer routes for cellulose-based functional materials. There has been a renewed interest in understanding the structural, mechanical, and optical properties of methylcellulose and its composites. This review focuses on the recent development in optically and mechanically tunable hydrogels derived from methylcellulose and methylcellulose-cellulose nanocrystal composites. We further discuss the application of the gels for preparing highly ductile and strong fibers. Finally, the emerging application of methylcellulose-based fibers as optical fibers and their application potentials are discussed.
ARTICLE | doi:10.20944/preprints202209.0065.v1
Subject: Biology, Ecology Keywords: Antarctica; microbial communities; refugia; metabarcoding; McMurdo Dry Valleys; soil biodiversity
Online: 5 September 2022 (13:39:20 CEST)
In the cold deserts of the McMurdo Dry Valleys (MDV) the suitability of soil for microbial life is determined by both contemporary processes and legacy effects. Climatic changes and accompanying glacial activity have caused local extinctions and geochemical changes to soil ecosystems over several million years, while high elevation refugia may have escaped these disturbances and existed under relatively stable conditions. This study describes the impact of historical glacial and lacustrine disturbance events on microbial communities across the MDV. Soil bacterial communities from 17 sites representing either putative refugia or sites disturbed during the Last Glacial Maximum (LGM) (22-17kya) were characterized using 16S metabarcoding. Regardless of geographic distance, several putative refugia sites at elevations above 600 meter displayed highly similar microbial communities. At a regional scale, community composition was found to be influenced by elevation and geographic proximity more so than soil geochemical properties. These results suggest that despite the extreme conditions, diverse microbial communities exist in these putative refugia that have presumably remained undisturbed at least through the last glacial maximum. We suggest that similarities in microbial communities can be interpreted as evidence for historical climate legacies on an ecosystem-wide scale.
ARTICLE | doi:10.20944/preprints202207.0267.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Dioscorea; yield stability; environments; genotype; dry matter; disease resistance; Uganda
Online: 18 July 2022 (10:56:10 CEST)
Often yam varieties grown in different agro-ecologies show differential responses across production environments, a term known as genotype-by-environment interaction. Genotype-by-environment interaction makes selecting the best genotypes under varied production environments more complex. This study tested twenty yam genotypes evaluated in six test environments to assess genotype, environment, and the interaction between genotypes and environmental effect for tuber yield, yam mosaic virus, and dry matter content. The experiments were conducted in two seasons across three locations in Uganda using a randomized complete block design with three replications. The results showed a significant effect (p ≤ 0.001) for genotype (G), environment (E), and genotype by environment interaction for all the traits. Serere 2021 and Namulonge 2021 were identified as the most discriminating and representative environments for testing the yam mosaic virus, respectively. Serere 2021 was recognized as the most discriminating environment, whereas Arua 2021 was identified as the closest to an ideal environment for assessing yam tuber yields. The tested genotypes also exhibited high resistance to yam mosaic virus disease, high tuber yields, and high dry matter content. Genotypes UGY16020, UGY16034, UGY16042, and UGY16080 demonstrated great resistance to yam mosaic virus disease, high yielding, and considerable dry matter content and are thus potential parents for yam improvement. Further evaluation of the four genotypes should be done under farmers' production systems for selection, improvement, and release as new yam varieties for Uganda
ARTICLE | doi:10.20944/preprints202112.0237.v1
Subject: Life Sciences, Other Keywords: religious fasting; daytime dry fasting; energy expenditure; body composition; microdialysis
Online: 14 December 2021 (13:06:26 CET)
Each year in March, adherents of the Bahá’í faith abstain from eating and drinking from sunrise to sunset for 19 days. Thus, Bahá’í fasting (BF) can be considered as a form of daytime dry fasting. We tested if BF decreases energy expenditure after a meal and improves anthropometric measures, and systemic and tissue-level metabolic parameters. This was a self-controlled cohort study with 11 healthy men. We measured anthropometric parameters, metabolic markers in venous blood, and pre- and postprandial energy metabolism at systemic (indirect calorimetry) and tissue (adipose tissue and skeletal muscle microdialysis) level, both before and during BF. During BF, we found reduced body weight, body mass index, body fat and blood glucose. Postprandial increase in energy expenditure was lower, diet-induced thermogenesis tended to be lower. In adipose tissue, perfusion, glucose supply and lipolysis were increased. In skeletal muscle, tissue perfusion did not change. Glucose supply and lipolysis were decreased. Glucose oxidation was increased, indicating an improved insulin sensitivity. BF may be a promising approach to losing weight and improving metabolism and health. However, outside the context of religiously-motivated fasting, skipping a meal rather in the evening (dinner cancelling) might be recommended, as metabolism appears to be reduced in the evening.
ARTICLE | doi:10.20944/preprints202107.0423.v1
Subject: Life Sciences, Biochemistry Keywords: non-conventional yeasts; Saccharomyces; fermentation; beer; dry-hopping; brewing potential
Online: 19 July 2021 (16:08:39 CEST)
Consumer demands for new sensory experiences have driven the research of unconventional yeasts in beer. While much research exists on the use of various common Saccharomyces cerevisiae strains as well as non-Saccharomyces yeasts, there exists a gap in knowledge regarding other non-cerevisiae Saccharomyces species in the fermentation of beer, outside that of S. pastorianus. Here, five distinct species of Saccharomyces from the UC Davis Phaff Yeast Culture Collection, as well as one interspecies hybrid from Fermentis, were chosen to ferment 40 L pilot scale beers. S. kudriavzevii, S. mikatae, S. paradoxus, S. bayanus, and S. uvarum yeasts were fermented in duplicate, with one fermenter in each pair receiving 10 g/L dry-hop during fermentation. Analytical measurements were made each day of fermentation and compared to controls of SafAle US-05 and SafLager W 34/70 for commercial brewing parameters of interest. Finished beers were also analyzed for aroma, taste, and mouthfeel to determine the flavor of each yeast as it pertains to brewing potential. All beers exhibited spicy characteristics, likely from the presence of phenols; dry-hopping increased fruit notes while also increasing perceived bitterness and astringency. All of the species in this study displayed great brewing potential, and might be an ideal addition to beer depending on a brewery’s desire to experiment with flavor and willingness to bring a new yeast into their production environment
ARTICLE | doi:10.20944/preprints201912.0376.v1
Subject: Medicine & Pharmacology, Ophthalmology Keywords: dry eye; tear break-up time; intra-ocular pressure; seasonality
Online: 29 December 2019 (09:17:39 CET)
Purpose: To evaluate seasonal variation in intra-ocular pressure (IOP) with and without short tear break-up time (SBUT, BUT ≤ 5 s). Methods: This study enrolled 176 patients who visited one of six eye clinics in Japan for IOP measurement at every season. The mean patient age was 67.9 years, including 79 males. We compared the seasonal variation in IOP (mean ± SD) across spring (Mar-May), summer (Jun-Aug), fall (Sep-Nov), and winter (Dec-Feb). Results: The IOP (mmHg) in winter and summer, respectively, was 12.8 ± 3.7 and 12.8 ± 3.1 for non-glaucoma patients without SBUT (n = 47, P = 0.964), 14.8 ± 3.4 and 13.3 ± 3.4 for non-glaucoma patients with SBUT (n = 57, P < 0.001), 14.3 ± 3.2 and 14.1 ± 3.4 for glaucoma patients without SBUT (n = 36, P = 0.489), and 13.3 ± 3.0 and 11.6 ± 2.9 for glaucoma with SBUT (n = 36, P < 0.001). Seasonal variation was largest across the seasons in the glaucoma with SBUT group, and the magnitude of seasonal variation correlated with BUT (β = 0.228, P = 0.003). Conclusions: Seasonal variation tended to be larger in patients with SBUT than those without SBUT.
ARTICLE | doi:10.20944/preprints201812.0083.v1
Subject: Biology, Ecology Keywords: post-mining regeneration; succession; tropical dry forest; post-mining recovery
Online: 6 December 2018 (11:04:06 CET)
Open pit mining is a common activity in the Yucatan peninsula for the extraction of limestone. This mining is known under the generic name of quarries, and regionally as sascaberas (sascab=white soil in Mayan language). These areas are characterized by the total removal of the natural vegetation cover and soil in order to have access to the calcareous material. The present study shows the composition and structure of the vegetation in five quarries after approximately ten years of abandonment, and the conserved vegetation near to each one of the quarries in southeastern Quintana Roo. Using a canonical correspondence analysis (CCA), the distribution of the species was determined in relation to the edaphic variables: soil depth, percentage of organic matter (OM), cationic exchange capacity (CEC), pH and texture. 26 families, 46 genera and 50 species were recorded in the quarries and 25 families, 45 genera and 47 species were recorded in the conserved areas. The dominant species in the quarries belong to the families Poaceae, Fabaceae, Rubiaceae and Anacardiaceae. The quarries with higher values of OM (1.63%), CEC (24.05 Cmol/kg), depth (11 cm) and sand percentage (31.33%) include the following species like Lysiloma latisiliquum, Metopium brownei and Bursera simaruba which are commonly found in secondary forests. On the other hand, quarries with lower values of OM (0.39%), CEC (16.58 Cmol/kg) and depth (5.02), and higher percentage of silt (42.44%) were dominated by herbaceous species belonging to the Poaceae family and by Borreria verticillata, which are typical in disturbed areas of southeastern Mexico. In all cases, the pH was slightly alkaline due to the content of calcium carbonate (CaCO3), characteristic of the soils of the region. The edaphic variables are significantly correlated with the development and distribution of vegetation, and with the structure of the communities.
ARTICLE | doi:10.20944/preprints201711.0045.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: adoption; land-use; degradation; ethnobotany; networking; agroforestry; dry semi-deciduous
Online: 7 November 2017 (04:06:23 CET)
Bamboo agroforestry is currently being promoted as a viable land use option to reduce dependence on natural forest for wood fuels in Ghana. To align the design and introduction of bamboo agroforestry in conformity with farmers’ needs, perceptions, skills and local cultural practices, information on its acceptability and adoption potential among farmers is necessary. It is therefore the objective of this study to (1) describe bamboo ethnobotany and (2) assess socioeconomic factors that affect the acceptability and adoption of bamboo and its integration into farming practices. Accordingly, information has been collected from 200 farmers in the dry semi-deciduous forest zone of Ghana. The study identified the socioeconomic risks and uncertainties as well as biophysical factors that are likely to influence the potential adoption of bamboo agroforestry in the study region. Gender, age, farmers’ known uses of bamboo, the practice of leaving trees on farmlands, farmers’ networking and access to extension services, land availability and ownership by farmers were identified as suitable predictor variables for the adoption of bamboo agroforestry. It is envisaged that bamboo agroforestry is a good bet in the DSFZ though there is the need to explore domestic energy (fuelwood) provision and substitution potential in order to have a broader picture of the technology.
ARTICLE | doi:10.20944/preprints201705.0092.v1
Subject: Life Sciences, Other Keywords: livestock; stover; lucerne; maize; bull; animals; dry matter; protein; cottonseed
Online: 11 May 2017 (05:04:11 CEST)
The experiment was conducted at livestock research and development station surezai Peshawar during March 2012 to study the effect of cotton seed cake, Lucerne hay supplementation on intake of maize stover and weight gain by male sahiwal bull. Twelve (12) young Sahiwal bull breed, 280 kg average liveweight and 2 years of age were randomly put into 4 groups of 3 animals under intensive feeding system to determine the effect of different protein supplements on growth, and intake of chopped, dried maize stover. A control group was fed stover adlibitum only, and the other groups were fed daily 750 g cottonseed cake/head, 1 kg lucerne hay or 900 g of lucerne/cottonseed cake (66:34; w/w). Significant differences were observed on average daily live weight gains. Animals on lucerne and its mixture registered higher daily gains (243 g) and (330 g) respectively, followed by cottonseed cake (156 g); the control group lost weight (-8.0 g/d). Contrary to the live weight gains, animals fed on lucerne and its mixture had lower maize stover intakes, 3.35 kg DM/animal/day and 3.70 kg DM respectively, while those on cottonseed cake and the control group ingested respectively 4.72 kg DM and 4.16 kg DM maize Stover. It is concluded that during the critical period in the suburb of Peshawar, small-scale farmers can prevent loss in live weight by utilizing simple available rations.
ARTICLE | doi:10.20944/preprints202001.0300.v1
Subject: Earth Sciences, Other Keywords: snow; synthetic aperture radar; Sentinel-1; spatial variability; spectral scaling; topography; wet snow
Online: 26 January 2020 (01:42:48 CET)
This study investigates the spatial signatures of seasonal snow in Synthetic Aperture Radar (SAR) observations at different spatial scales and for different physiographic regions. Sentinel-1 C-band (SAR) backscattering coefficients (BSC) were analyzed in the Swiss Alps (SA), in high elevation forest and grasslands in Grand Mesa (GM), Colorado, and in North Dakota (ND) croplands. GM BSC exhibit 10dB sensitivity to wetness at small scales (~100 m) over homogeneous grassland. Sensitivity decreases to 5 dB in the presence of trees, and it is demonstrated that VH BSC sensitivity enables wet snow mapping below the tree-line. Area-variance scaling relationships show minima at ~100 m and 150-250 m respectively in barren and grasslands in SA and GM, increasing up to 1 km and longer in GM forests and ND agricultural fields. The spatial organization of BSC (as described by 1D-directional BSC wavelength spectra) exhibits multi-scaling behavior in the 100 -1,000 m range with a break at (180-360 m) that is also present in UAVSAR L-band measurements in GM. Spectral slopes in GM forested areas steepen during accumulation and flatten in the melting season with mirror behavior for grasslands reflecting changes in scattering mechanisms with snow depth and wetness, and vegetation mass and structure. Overall, this study reveals persistent patterns of SAR scattering variability spatially organized by land-cover, topography and regional winds with large inter-annual variability tied to precipitation. This dynamic scaling behavior emerges as an integral physical expression of snowpack variability that can be used to model sub-km scales and for downscaling applications.
ARTICLE | doi:10.20944/preprints201811.0562.v1
Subject: Chemistry, Analytical Chemistry Keywords: charcoal; dry heat cooking; indoor; meat; N-nitrosodimethylamine; health risk; source
Online: 23 November 2018 (13:59:34 CET)
This study aimed to investigate the airborne release of N-nitrosodimethylamine (NDMA) as a result of the dry heat cooking of some meats using charcoal grilling and pan broiling methods. Three types of meat, beef sirloin, pork belly, and duck, were chosen and cooked in a temporary building using the above methods. Air samples were collected in Thermosorb-N cartridges, which were qualitatively and quantitatively analyzed for NDMA using ultra-high performance liquid chromatography–mass spectrometry and high-performance liquid chromatography–fluorescence detection, respectively. Overall, the charcoal grilling method showed higher average NDMA concentrations than the pan broiling method for all types of meat. The highest average concentration was observed for charcoal-grilled beef sirloin (410 ng/m3) followed by pork belly, suggesting that meat protein content and cooking duration are important determinants of NDMA formation. Cancer risk assessment showed that the charcoal grilling of such meats can pose an additional cancer risk for restaurant customers.
ARTICLE | doi:10.20944/preprints201703.0168.v1
Subject: Materials Science, Metallurgy Keywords: Al-Zn-Cr Alloys; powder metallurgy; strengthening; extrusion; dry sliding wear
Online: 21 March 2017 (04:26:13 CET)
Aluminum base alloys containing chromium (Cr) and zinc (Zn) were produced using extrusion and heat treated powder metallurgy. Cr addition ranged between 5 to 10 wt. % while Zn was added in an amount between 0 to 20 wt. %. Heat treatment processes were performed during powder metallurgy process at different temperatures followed by water quenching. Similar alloys were extruded, with an extrusion ratio of 4.6 to get proper densification. Optical microscopy was used for microstructure investigations of the produced alloys. The element distribution microstructure study was carried out using the Energy Dispersive X-ray analysis method. Hardness and tensile properties of the investigated alloys have been examined. Wear resistance tests were carried out and the results were compared with these of the Al-based bulk alloys. Results showed that the aluminum base alloys containing 10wt. % Chromium and heat treated at 500°C for one hour followed by water quenching exhibited the highest wear resistance and better mechanical properties.
ARTICLE | doi:10.20944/preprints202106.0585.v1
Subject: Medicine & Pharmacology, Allergology Keywords: Triamcinolone acetonide; Liposomes; Neovascular age related macular degeneration; Wet macular degeneration; Adjuvant therapy; Ranibizumab
Online: 23 June 2021 (12:56:55 CEST)
Novel strategies have been developed to reduce or to avoid the intravitreal injections (IVTs) of the antiangiogenic (ranibizumab; RBZ) and the anti-inflammatory (triamcinolone acetonide; TA) agents used to treat vitreoretinal diseases. One of the strategies include liposomes. In this study, it was evaluated the safety and efficacy of topical triamcinolone-loaded liposomes formulation (TALF) as an adjuvant to intravitreal RBZ therapy in treatment-naive patients with neovascular age related macular degeneration (nAMD). Subjects were randomly assigned to the RBZ-TALF or the RBZ-pro re nata (RBZ-PRN) group. Patients from the RBZ-TALF group were instructed to apply TALF for a 12-month period after a single dose of RBZ. Patients from the RBZ-PRN group received three monthly RBZ-IVTs. Retreatment with RBZ was considered in case of nAMD reactivation. Related to safety, non-ocular abnormalities were observed during TALF therapy. Owing to the efficacy, non-significant differences are identified in visual acuity or central foveal thickness when the RBZ-PRN and RBZ-TALF groups are compared. Importantly the average number of RBZ injections was significantly lower in the RBZ-TALF group (2.5 ± 1.4 vs 6.1 ± 1.3 IVTs; p=0004). Therefore, TALF used as an adjuvant to RBZ reduce the number of RBZ-IVTs retreatment with optimal visual and anatomic results.
ARTICLE | doi:10.20944/preprints202106.0120.v1
Subject: Earth Sciences, Atmospheric Science Keywords: IMERG; Stage IV; Infrared; Passive microwave; Snow; Ice; Precipitation; GPM; Wet-bulb temperature; AMSR-2
Online: 3 June 2021 (14:59:21 CEST)
Various products of the Integrated Multisatellite Retrievals for GPM (IMERG) and passive mi-crowave (PMW) sensors are assessed with respect to near-surface wet-bulb temperature (Tw), precipitation intensity, and surface type (i.e., with and without snow and ice on the surface) over the CONUS and using Stage-IV product as reference precipitation. IMERG products include precipitation estimates from infrared (IR), combined PMW, and their combination. PMW products generally have higher skills than IR over snow- and ice-free surfaces. Over snow- and ice-covered surfaces (1) PMW products (except AMSR-2) show a higher correlation coefficient than IR, (2) IR and PMW precipitation products tend to overestimate precipitation, but at colder temperatures (e.g., Tw<-10oC) PMW products tend to underestimate and IR product continues to show large overestimations, and (3) PMW sensors show higher overall skill in detecting precipitation oc-currence, but not necessarily at very cold Tw. The results suggest that the current approach of IMERG (i.e., replacing PMW with IR precipitation estimates over snow- and ice-surfaces) may need to be revised.
ARTICLE | doi:10.20944/preprints202103.0725.v1
Subject: Life Sciences, Biochemistry Keywords: dry matter yield; nutrient uptake; soil nutrient reserves; co-application; grain yield; dryland
Online: 30 March 2021 (10:18:06 CEST)
Most smallscale farmers still use the traditional way of agricultural crop farming, and relay mostly use of chemical fertilizers (CF). Recently CF have become expensive and could in some way have a negative impact on soil quality after long term application. However, co-application of biogas slurry (BGS) with CF could help reduce farming costs while improving dry matter yields, grain yields, primary macronutrient uptake of (Nitrogen) N, (Phosphorus) P, (Potasium) K, (Calcium) Ca and (Magnesium) Mg and soil concentration of pH, (organic carbon) OC, N, P, K, Ca and Mg after crop harvest. The study was a field experiment conducted in 2016-2017 and 2017-2018 growing seasons. The field experiment was arranged in a randomized complete block design with four replicates. The treatments were based on percentages of recommended N rates of 120 kg N ha-1 for maize production. The BGS/CF treatments were (i) 0/0, (ii) 0/120, (iii) 24/96, (iv) 48/72, (v) 72/48, (vi) 96/24, (vii) 120/0 kg N ha-1. The spreading of the combination of BGS/CF treatments was performed by hand and incorporated into the top soil (0-10 cm) in each experimental plots. BGS/CF (48/72) treatment resulted into higher dry matter yield in 2016-2017, which was higher than all other treatment combinations, while in the 2017-2018 season, treatment of (0/120) resulted into higher dry matter than all other treatment combinations. The 48/72 and 0/120 treatments resulted into similar grain yield in 2016-2017 season which were higher than all other treatments. Treatments of 48/72, 72/48 and 120/0 had higher N, P, K, Ca and Mg uptake than 0/0, 0/120, 24/96 and 96/24 treatments in both seasons. Soil pH, total N, K, and Mg were high from the treatment of (120/0) than all other treatments in 2016-2017 while in the 2017-2018 season, treatment of (48/72) had higher OC, P and K after maize harvest. The findings of his study show that co-application of BGS/CF at 48/72 and 72/48 have maize yield benefits compared to the two resources, BGS/CF (120/0) and BGS/CF (0/120), applied separately in soil especially in the arid and semi-arid regions.
Subject: Life Sciences, Biophysics Keywords: statistical mechanics; resource partitioning; distribution of species; seasonally dry tropical forest; biotic resistance
Online: 3 April 2019 (10:36:47 CEST)
Data on the seasonally dry tropical forests of Mexico have been examined in the light of statistical mechanics. The results suggest a division into two classes of species. There are drifting populations of a cosmopolitan class capable of existing in most dry forest sites; these have a statistical distribution previously only observed (globally) for populations of alien species. A high proportion of species found only at a single site are endemic and these prefer sites comparatively low in species richness.
ARTICLE | doi:10.20944/preprints202104.0222.v1
Subject: Medicine & Pharmacology, Allergology Keywords: ocular surface disease; dry eye disease; antioxidant; Xanthohumol; drug delivery; drug formulation; PLGA; nanoparticles
Online: 8 April 2021 (09:09:24 CEST)
Elevated levels of oxidative stress in the corneal epithelium contribute to the progression of dry eye disease pathology. Previous studies have shown that antioxidant therapeutic intervention is a promising avenue to reduce disease burden and slow disease progression. In this study, we evaluated the pharmacological efficacy of Xanthohumol in preclinical models for dry eye disease. Xanthohumol is a naturally occurring prenylated chalconoid that promotes the transcription of phase II antioxidant enzymes. Xanthohumol exerted a dose-response in preventing tert-butylhydroxide-induced loss of cell viability in human corneal epithelial (HCE-T) cells and resulted in a significant increase in expression of nuclear factor erythroid 2-related factor 2 (Nrf2), the master regulator of the endogenous antioxidant system. Xanthohumol-encapsulating poly(lactic-co-glycolic acid) nanoparticles (PLGA NP) were cytoprotective against oxidative stress in vitro, and significantly reduced corneal fluorescein staining in the mouse desiccating stress/ scopolamine model for dry eye disease in vivo by reducing oxidative stress-associated DNA damage in corneal epithelial cells. PLGA NP represent a safe and efficacious drug delivery vehicle for hydrophobic small molecules to the ocular surface. Optimization of NP-based antioxidant formulations with the goal to minimize instillation frequency may represent future therapeutic options for dry eye disease and related ocular surface disease.
COMMUNICATION | doi:10.20944/preprints202002.0057.v1
Subject: Materials Science, Biomaterials Keywords: porous fibers; activated carbon; ice-templating; ice segregation induced self-assembly; silk fibroin; wet spinning; solution blow spinning
Online: 5 February 2020 (10:38:29 CET)
Fabrics comprised of porous fibers could provide effective passive protection against chemical and biological (CB) threats whilst maintaining high air permeability (breathability). Here, we fabricate hierarchically porous fibers consisting of regenerated silk fibroin (RSF) and activated-carbon (AC) prepared through two fiber spinning techniques in combination with ice-templating – namely cryogenic solution blow spinning (Cryo-SBS) and cryogenic wet-spinning (Cryo-WS). The Cryo-WS RSF fibers had exceptionally small macropores (as low as 0.1 µm) and high specific surface areas (SSAs) of up to 79 m2 g-1. The incorporation of AC could further increase the SSA to 210 m2 g-1 (25 wt. % loading) whilst also increasing adsorption capacity for volatile organic compounds (VOCs).
ARTICLE | doi:10.20944/preprints202105.0453.v1
Subject: Life Sciences, Biochemistry Keywords: dairy cattle; prediction model; methane conversion factor; dry matter intake; fatty acid; neutral detergent fiber
Online: 19 May 2021 (16:49:00 CEST)
The aim of this study was to develop a basic model to predict enteric methane emission from dairy cows and to update operational calculations for the national inventory in Norway. Basic models were developed using a database with 63 treatment means from 19 studies. The database included records for enteric CH4 production (MJ/day), dry matter intake (DMI), and dietary nutrient composition. The basic models were evaluated against an external database (n=36, from ten studies) along with other extant models. When evaluated by low root mean square prediction errors and high concordance correlation coefficients, the developed basic models that included DMI, dietary concentrations of fatty acids and neutral detergent fiber performed slightly better in predicting CH4 emissions than extant models. In order to propose country-specific values for the CH4 conversion factor Ym (% of gross energy intake partitioned into CH4) and thus to carry out the national inventory for Norway, the existing operational model was updated for the prediction of Ym over a wide range of feeding situations using energy corrected milk and dietary concentrate share as predictor variables. Input values of Ym were updated based on the results from the basic models. The predicted Ym ranged from 6.22 to 6.72%. In conclusion, the prediction of CH4 production from dairy cows was improved with the help of newly published data, which enabled an update of the operational model for calculating the national inventory of CH4 in Norway.
COMMUNICATION | doi:10.20944/preprints202104.0273.v1
Subject: Medicine & Pharmacology, Allergology Keywords: Dry-AMD; oxidative stress; MnSOD; RPE; retinal degeneration; Erythropoietin; gene therapy; Animal model; AAV; ERG
Online: 12 April 2021 (09:37:18 CEST)
Erythropoietin (EPO) protects cells by inhibiting apoptosis, oxidative stress and inflammation in several models of retinal degeneration. In this study, we demonstrate the effects of recombinant Adeno Associated Virus (AAV) vector-mediated delivery of a modified form of erythropoietin (EPO-R76E) in an established mouse model of dry-AMD in which retinal degeneration is induced by RPE oxidative stress. Experimental vector AAV-EPO-R76E and control vector AAV-GFP were packaged into serotype-1 (AAV1) to enable RPE selective expression. RPE oxidative stress-mediated retinal degeneration was induced by exon specific deletion of the protective enzyme MnSOD (encoded by Sod2) by cre/lox mechanism. Experimental mice received subretinal injection of AAV-EPO-R76E in the right eye and AAV-GFP in the left eye. Western blotting of RPE/Choroid protein samples from AAV-EPO-R76E injected eyes showed RPE specific exogenous protein expression. Retinal degeneration was monitored by electroretinography (ERG). EPO-R76E over-expression in RPE delayed the progressive retinal degeneration as measured by light microscopy in RPE specific Sod2 knockout mice. Delivery of EPO-R76E vector can be used as a tool to prevent retinal degeneration induced by RPE oxidative stress as seen in this mouse model.
ARTICLE | doi:10.20944/preprints202010.0216.v1
Subject: Earth Sciences, Atmospheric Science Keywords: cascading tank village system; sustainable livelihoods; resilience thinking; Sri Lanka; rural dry zone; community rural development
Online: 12 October 2020 (09:47:15 CEST)
Cascading Tank Village Systems (CTVSs) of Sri Lanka historically provided a resilient community-based social-ecological water management system in the rural dryzone of Sri Lanka . The CTVS has been described as the ‘lifeblood’ of communities in the rural dry zone  and as a globally important Agricultural Heritage System by the FAO . After being abandoned for many centuries, their restoration is now being pursued by different national and international actors as a key to climate change mitigation and sustainable livelihoods for communities . Rural livelihoods in the dry zone are at risk due to multiple factors, poor access and management of water, economic and health pressures, as well as resource limitations and degradation . Despite recent efforts to restore CTVS systems, no social-ecological approach (SES) nor sustainable livelihoods framework (SLF) focused approach to ensuring resilient and sustainable livelihood outcomes has been taken . As part of an on-going PhD project, this paper describes the background, current challenges and potential for an SES focused resilience thinking approach to CTVS combined with a focus on sustainable livelihoods for future sustainable livelihood opportunities and outcomes. The study finds current restoration efforts are at a crossroads between restoring the past (system adaptability) or transforming for the future. It introduces relevant SES and resilience thinking concepts and analyses the CTVS from this perspective. A particular contribution of this study is to point to the significant overlaps and complementarities in social-ecological (SES) resilience thinking and SLF approaches to analysis and proposals for resilient rural development. Employing resilience thinking principles it recommends strategies to create positive livelihood outcomes for communities and households. Keywords: cascading tank village system; sustainable livelihoods; resilience thinking; Sri Lanka; rural dry zone; community rural development
ARTICLE | doi:10.20944/preprints202103.0418.v1
Subject: Earth Sciences, Atmospheric Science Keywords: tree vigor; ponderosa pine; remote sensing; aerial imagery; dry pine forest; fuel treatments; forest restoration; random forest
Online: 16 March 2021 (11:58:20 CET)
Ponderosa pine is an integral part of the forested landscape in the western US; it is the dominant tree species on landscapes that provide critical ecosystem services. Moderate drought tolerance allows it to occupy the transition zone between forests and open woodlands and grasslands. Increases in stand density resulting from wildfire suppression, combined with lengthening, intensifying and more frequent droughts have resulted in reduced tree vigor and stand health in dry ponderosa pine throughout its range. To address a management need for efficient landscape-level surveys of forest health, we used Random Forests to develop an object-oriented classification of individual tree crowns (ITCs) into vigor classes using existing, agency acquired 4-band aerial imagery. Classes of tree vigor were based on quantitative physiological and morphological attributes established in a previous study. We applied our model across a landscape dominated by ponderosa pine with a variety of forest treatments to assess their impacts on tree vigor and stand health. We found that stands that were both thinned and burned had the lowest proportion of low vigor ITCs, and that stands treated before the 2014-2016 drought had lower proportions of low vigor ITCs than stands treated more recently (2016). Upland stands had significantly higher proportions of low vigor trees than lowland stands. Maps identifying the low vigor ITCs would assist managers in identifying priority stands for treatment and marking trees for harvest or retention. These maps can be created using already available imagery and GIS software.
ARTICLE | doi:10.20944/preprints202103.0017.v1
Subject: Medicine & Pharmacology, Allergology Keywords: dry eye disease; meibomian gland; tear stability; tear film lipid layer; interferometry; OSDI; intense pulse light; IPL
Online: 1 March 2021 (13:45:51 CET)
Background: Inadequate meibomian glands (MGs) secretion can lead to dry eye signs and symptoms. Tear film lipid layer (TFLL) secreted by MGs protects and prevents rapid evaporation of tear film. Our purpose was to assess TFLL alteration and function in patients with evaporative dry eye (EDE) using tear interferometry after optimal pulse light technology (OPT) intense pulsed light (IPL). Methods: This prospective randomized examiner-masked sham- controlled study included 86 participants (142 eyes) with DED. IPL or sham procedure was performed on day 0, 21, and 42. Ocular Surface Disease Index (OSDI), non-invasive breakup time (NITBUT), interferometric fringe pattern determined TFLL quality, fluorescein staining (FS), and meibum gland (MG) were assessed at day 0, 21, 42 and 3-month. Results: At 3-month, TFLL, NITBUT, MG drop-out, MG quality, MG expressibility, FS and OSDI improved significantly (P<0.05) in the IPL group, while the sham group had no significant improvements. All DE parameters significantly correlated with the improvement in TFLL following IPL treatment. Additionally, artificial tears usage was significantly less in the IPL group from D-42 onwards. Conclusion: IPL treatment demonstrated the ability to improve TFLL quality and clinically reduced sign and symptoms of DED thereby reducing the frequency of artificial tears usage.
REVIEW | doi:10.20944/preprints202011.0152.v1
Subject: Mathematics & Computer Science, Algebra & Number Theory Keywords: EEG signal recognition; machine learning in EEG; neural networks in EEG; dry electrode EEG; deep learning EEG
Online: 3 November 2020 (14:07:29 CET)
In the last decade, unprecedented progress in the development of neural networks influenced dozens of different industries, among which are signal processing for the electroencephalography process (EEG). Electroencephalography, even though it appeared in the first half of the 20th century, to this day didn’t change the physical principles of operation. But the signal processing technique due to the use of neural networks progressed significantly in this area. Evidence for this can serve that for the past 5 years more than 1000 publications on the topic of using machine learning have been published in popular libraries. Many different models of neural networks complicate the process of understanding the real situation in this area. In this manuscript, we provided the most comprehensive overview of research where were used neural networks for EEG signal processing.
REVIEW | doi:10.20944/preprints201705.0161.v1
Subject: Medicine & Pharmacology, Ophthalmology Keywords: dry eye; lacrimal gland; lipids and lipidomics; Meibomian gland; ocular surface disorders; proteins and proteomics; tear film
Online: 22 May 2017 (07:54:47 CEST)
The alteration of the delicate balance that regulates the secretion and distribution of the tear film determines the dry eye (DE) syndrome, because the tear film represents the interface between the eye and the environment. Despite having a multifactorial origin, the main risk factors for the emergence of the ocular disease are female gender and advanced age. Likewise, morphological changes in several glands and in chemical composition of their secretions such as proteins, mucins, lipidics, aqueous tears, and salinity, are highly relevant factors to maintain a condition of good health of the ocular anterior segment. Another key factor of recurrence and onset of the disease is the presence of local and/or systemic infiammation that reflex on the ocular surface. However, it is one of the most commonly encountered disease in clinical practice and many other causes related to daily life and to lengthen the average life will contribute to the beginning. This review will consider how and what disorders of the ocular surface are responsible for a widespread pathology so. In the end, the most appropriate and new therapies will be briefly exposed according to the specific pathology.
ARTICLE | doi:10.20944/preprints201809.0078.v1
Subject: Engineering, Energy & Fuel Technology Keywords: Ethanol; corn; dry-grind process; bolt-on process; corn fiber; soaking in aqueous ammonia pretreatment; cellulase; cellulosic ethanol.
Online: 5 September 2018 (01:40:11 CEST)
Corn fiber is a co-product of commercial ethanol dry-grind plants, which is processed into distillers dried grains with solubles (DDGS) and used as animal feed, yet it holds high potential to be used as feedstock for additional ethanol production. Due to the tight structural make-up of corn fiber, a pretreatment step is necessary to make the cellulose and hemicellulose polymers in the solid fibrous matrix more accessible to the hydrolytic enzymes. A pretreatment process was developed in which whole corn kernels were soaked in aqueous solutions of 2.5, 5.0, 7.5 and 10.0 wt% ammonia at 105oC for 24 h. The pretreated corn then was subjected to a conventional mashing procedure and subsequently ethanol fermentation using a commercial strain of natural Saccharomyces cerevisiae with addition of a commercial cellulase. Pretreatment of the corn with 7.5 wt% ammonia solution plus cellulase addition gave highest ethanol production, which improved the yield in fermentation using 25 wt% solid from 334 g ethanol/kg corn obtained in the control (no pretreatment and no cellulase addition) to 379 g ethanol/kg corn (a 14% increase). The process developed can potentially be implemented in existing dry-grind ethanol facilities as a “bolt-on” process for additional ethanol production from corn fiber, and this additional ethanol can then qualify as “cellulosic ethanol” by the EPA’s Renewable Fuels Standard and thereby receive RINS (Renewable Identification Numbers).
REVIEW | doi:10.20944/preprints201903.0164.v1
Subject: Engineering, Electrical & Electronic Engineering Keywords: smart garments; e-textiles; biosignals; sensors; dry electrode; signal-to-noise ratio (SNR); internet-of-things (IoT); knitted fabrics
Online: 15 March 2019 (11:59:47 CET)
This paper presents an overview of the smart electro-clothing systems (SeCSs) targeted at health monitoring, sports benefits, fitness tracking, and social activities. Technical features of the available SeCSs, covering both textile and electronic components, are thoroughly discussed and their applications in the industry and research purposes have been highlighted. In addition, it also presents the developments in the associated areas of wearable sensor systems and textile-based dry sensors. As it became evident during the literature research, such a review on SeCSs covering all relevant issues has not been presented before. This paper will be particularly helpful for new generation researchers investigating the design, development, function and comforts of the sensor integrated clothing materials.
ARTICLE | doi:10.20944/preprints202110.0195.v1
Subject: Medicine & Pharmacology, General Medical Research Keywords: respirable agglomerates; inhaled corticosteroids; ciclesonide; particle engineering; dry powder inhaler; extrafine; total lung dose; Alberta Idealized Throat; Idealized Child Throat
Online: 13 October 2021 (10:52:57 CEST)
Current dry powder formulations for inhalation deposit a large fraction of their emitted dose in the upper respiratory tract where they contribute to off-target adverse effects and variability in lung delivery. The purpose of current study is to design a new formulation concept that more effectively targets inhaled dry powders to the large and small airways. The formulations are based on adhesive mixtures of drug nanoparticles and nanoleucine carrier particles prepared by spray drying of a co-suspension of leucine and drug particles from a nonsolvent. The physicochemical and aerosol properties of the resulting formulations are presented. The formulations achieve 93% lung delivery in the Alberta Idealized Throat model that is independent of inspiratory flow rate and relative humidity. Largely eliminating URT deposition with a particle size larger than solution pMDIs is expected to improve delivery to the large and small airways, while minimizing alveolar deposition and particle exhalation.
REVIEW | doi:10.20944/preprints201902.0101.v1
Subject: Medicine & Pharmacology, Ophthalmology Keywords: age-related macular degeneration; anti-inflammatory agents; dry AMD; geographic atrophy; intravitreal injection; complement inhibitors; neuroprotective agents; non-exudative AMD
Online: 12 February 2019 (11:00:52 CET)
The present review focuses on recent clinical trials that analyze the efficacy of intravitreal therapeutic agents for the treatment of dry age-related macular degeneration (AMD), such as neuroprotective drugs, and complement inhibitors, also called immunomodulatory or anti-inflammatory. A systematic literature search was performed to identify randomized controlled trials published prior to January 2019. Patients affected by dry AMD treated with intravitreal therapeutic agents were included. The changes in the correct visual acuity and the reduction in geographic atrophy progression were evaluated. Several new drugs have shown some promising results, including those targeting the complement cascade and agents called neuroprotective. The action potential of the two groups of drugs is to block the complement cascade model for immunomodulating agents, and prevent the degeneration and apoptosis of ganglion cells for the neuroprotectors, respectively. To the best of knowledge, and after extensive studies on the matter, there are still many investigations to be carried out on dry AMD in collaboration between researchers. They will have to identify truly effective molecules, understand the practical potential of pluripotent stem cells, and refine gene therapies. Only in-depth clinical trials will be able to allow the most appropriate and personalized treatments for each dry AMD patient.
ARTICLE | doi:10.20944/preprints202107.0488.v1
Subject: Engineering, Automotive Engineering Keywords: metal-polymer plain bearings; PA6 based polyamide composites; dispersed glass and carbon fibers; temperature; Young's modulus; maximum contact pressures and resource; boundary and dry friction
Online: 21 July 2021 (11:24:45 CEST)
It is known that the elastic characteristics of polyamides change with increasing temperature, in particular, the Young's modulus decreases significantly. This fact is practically not taken into account in design calculations of metal-polymer plain (MP) bearings, operating under conditions of the boundary and dry friction. The purpose of the study is the analysis of the effect of temperature on the change of the Young's modulus and, accordingly, the contact strength and triboresource according to the developed method of calculating MP bearings. MP bearings with a bushing made of polyamide PA6 reinforced with glass or carbon dispersed fibers were investi-gated. Quantitative and qualitative regularities of change of the maximum contact pressures and resource of the bearings at temperature increase under conditions of boundary and dry friction are established. The pressures in the bearing bushing made of PA6+30GF will be lower than for the bushing made of PA6+30CF. The resource of the bushing made of PA6+30CF will be significantly greater than for PA6+30GF. For thermoplastic polymers, the increase in temperature will have a useful practical effect due to the decrease in the rigidity of the polymer composites of the bearing bushing.
ARTICLE | doi:10.20944/preprints201803.0026.v1
Subject: Earth Sciences, Atmospheric Science Keywords: atmospheric dispersion modelling; backward Lagrangian stochastic model; atmospheric surface-layer; micrometeorological techniques; gaseous emissions; atmospheric ammonia; dry deposition; grassland; open-path measurements; differential optical absorption spectroscopy
Online: 3 March 2018 (12:04:50 CET)
A controlled ammonia (NH3) release experiment was performed at a grassland site to quantify the effect of dry deposition, at the field scale between the source and the receptors (NH3 measurement locations), on the estimates of emission rates by means of inverse dispersion modelling. NH3 was released for 3 hours at a constant rate of Q = 6.29 mg s−1 from a grid of 36 orifices spread over an area of 250 m2. The increase in line-integrated NH3 concentration was measured with open-path optical miniDOAS devices at different locations downwind of the artificial source. Using a backward Lagrangian stochastic (bLS) dispersion model (bLSmodelR), the fraction of the modelled release rate to the emitted NH3 (QbLS/Q) was calculated from the measurements of the individual instruments. QbLS/Q was found to be systematically lower than 1, on average between 0.69 and 0.91, depending on the location of the receptor. We hypothesized that NH3 dry deposition to grass and soil surfaces was the main factor responsible for the observed depletion of NH3 between source and receptor. A dry deposition algorithm based on a deposition velocity approach was included in the bLS modelling. Model deposition velocities were evaluated from a ‘big‑leaf’ canopy resistance analogy. Canopy resistances (generally termed Rc) that provided QbLS/Q = 1 ranged from 75 to 290 s m−1, showing that surface removal of NH3 by dry deposition can plausibly explain the original underestimation of QbLS/Q. The inclusion of a dry deposition process in dispersion modelling is crucial for emission estimates, which are based on concentration measurements of depositing tracers downwind of homogeneous area sources or heterogeneously distributed hot spots, such as e.g. urine patches on pastures in the case of NH3.