ARTICLE | doi:10.20944/preprints201609.0120.v1
Subject: Materials Science, Surfaces, Coatings & Films Keywords: CO2 enhanced capture; SBA-15 habilitation for CO2 sorption; desilication; silanol functionalization; covalent coordinated CO2 deposition
Online: 29 September 2016 (12:38:24 CEST)
Special preparation of SBA-15 materials has been carried out for creating adsorbents exhibiting an enhanced and selective adsorption toward CO2. This creation starts from an adequate conditioning of the silica surface, via a thermo-alkaline treatment to increase the population of silanol species on it. CO2 adsorption is only reasonably achieved when the SiO2 surface becomes aminated after put in contact with a solution of an amino alkoxide compound in the right solvent. Unfunctionalized and amine-functionalized substrates were characterized through X-ray diffraction, N2 sorption, Raman spectroscopy, electron microscopy, 29Si solid-state NMR, and NH3 thermal programmed desorption. These analyses proved that the thermo-alkaline procedure desilicates the substrate and eliminates the micropores (without affecting the SBA-15 capillaries), present in the original solid. NMR analysis confirms that the hydroxylated solid anchors more amino functionalizing molecules than the unhydroxylated material. The SBA-15 sample subjected to hydroxylation and amino- functionalization displays a high enthalpy of interaction, a reason why this solid is suitable for a strong deposition of CO2 but with the possibility of observing a low-pressure hysteresis phenomenon. Contrastingly, CH4 adsorption on amino-functionalized, hydroxylated SBA-15 substrates becomes almost 5 times lesser than the CO2 one, thus giving proof of their selectivity toward CO2.
ARTICLE | doi:10.20944/preprints202110.0321.v1
Subject: Arts & Humanities, Other Keywords: City of Proximity; Walkability; 15 Minute City; Urban Regeneration; Urban Enclaves; Green Military Barracks
Online: 22 October 2021 (09:04:56 CEST)
The concepts of accessibility and urban walkability are the cornerstones of urban policies for the contemporary city, called upon to adopt sustainable development models in line with the objectives of the 2030 Agenda and the ambitious objectives of the 'European Green Deal'. These concepts are closely linked to the paradigm of a sustainable city (livable, healthy and inclusive), founded on a system of quality public spaces and on a network of services and infrastructures, both tangible and intangible, capable of strengthening or building new relationships: social, economic and environmental. It is therefore necessary to recognize potential opportunities for connection and permeability in consolidated urban environments, very often fragmented and characterized by enclaves. Within this framework, the city of Cagliari represents an interesting case study as it is characterized by the presence of a series of military complexes, real 'enclaves' which condition the proximity connections and, more generally, the walkability. In this sense, building on previous research and analysis of policies and projects aimed at reintroducing, even partially, this military asset into civilian life (Green Barracks Project - GBP - 2019), this study proposes and applies a methodology to improve urban accessibility in a flexible network logic, where 'walkability' can become not only a moment of possible "choice" but the basis for planning oriented to the '15 min city' model or, more generally, to the renewed, inclusive, safe, resilient and sustainable “City of proximity”.
ARTICLE | doi:10.20944/preprints202111.0391.v1
Subject: Medicine & Pharmacology, Nutrition Keywords: celiac disease; orthorexia; eating disorders; ORTHO-15; nutrition
Online: 22 November 2021 (12:56:59 CET)
Evidence points to a link between gluten-free diet or celiac disease and eating disorders, but not with orthorexia. This study is the first to examine adults with celiac disease in terms of the prevalence of risk of orthorexia. The study included 130 adults diagnosed with celiac disease. The standardized ORTHO-15 questionnaire was used to assess the risk of orthorexia. Cronbach's alpha test was used to determine the reliability of the ORTHO-15 questionnaire. Eating habits of the subjects were assessed using a questionnaire. The effect of celiac disease on diet was assessed on a 5-point scale. A risk of orthorexia was found in 69% of subjects with celiac disease. A statistically significant (p<0.005) positive correlation was observed between age and ORTHO-15 test scores (rho=0.37). In the group with orthorexia risk, meals were more often self-prepared (93.3%) compared to those without orthorexia (80%) (p=0.023). For 80% of those at risk for orthorexia versus 20% without risk, mood was a factor influencing dietary choices (p=0.001). The study observed a strong association between celiac disease and the presence of orthorexia risk. The numerous risk factors for orthorexia suggest the need for holistic care, including nutritional and psychological support among individuals with celiac disease.
ARTICLE | doi:10.20944/preprints201703.0204.v1
Subject: Medicine & Pharmacology, Gastroenterology Keywords: alcohol; liver cirrhosis; selenium; interleukin-6; growth differentiation factor-15
Online: 27 March 2017 (16:12:33 CEST)
According to some authors, the serum selenium level is strongly associated with the severity of liver diseases including liver cirrhosis. The aim of the study was to determine the relationship between the concentration of selenium and pro-inflammatory and profibrotic cytokines – interleukin-6 (IL-6) and growth differentiation factor 15 (GDF-15) in patients with alcoholic liver cirrhosis. The parameters studied were determined in serum of 99 alcoholic liver cirrhosis patients divided based on the severity of disease according to the Child-Turcotte-Pugh criteria. In patients with liver cirrhosis, the serum selenium concentration was statistically lower whereas serum IL-6 and GDF-15 concentrations were higher than those in the control group. Moreover, the concentration of selenium negatively correlated with the levels of GDF-15 and IL-6. The above results may indicate a role of selenium deficiency in the pathogenesis and progression of alcoholic liver disease.
REVIEW | doi:10.20944/preprints202012.0144.v1
Subject: Life Sciences, Biochemistry Keywords: Antimicrobial resistance; blaCTX-M-15; genetic environment; mobile genetic elements; Africa
Online: 7 December 2020 (12:49:16 CET)
The most widely distributed blaCTX-M gene on a global scale is blaCTX-M-15. The dissemination has been associated with clonal spread and different types of mobile genetic elements. This study aimed to review and describe the genetic environments of blaCTX-M-15 gene detected from Enterobacteriaceae in published literature from Africa. A literature search for relevant articles was done through PubMed, and Google Scholars electronic databases, 43 articles from 17 African countries were included in the review based on the eligibility criteria. Insertion sequences were reported as part of the genetic environment of blaCTX-M-15 gene in 32 studies, integrons in 13 studies, and plasmids in 23 studies. In this review, five insertion sequences including ISEcp1, IS26, orf447, IS903, and IS3 have been detected associated with the genetic environment of blaCTX-M-15 in Africa. Seven different genetic patterns were seen in blaCTX-M-15 genetic environment. Insertion sequence ISEcp1 was commonly located upstream of the end of the blaCTX-M-15 gene while insertion sequence orf477 was located downstream. In some studies, ISEcp1 was truncated upstream of blaCTX-M-15 by insertion sequences IS26 and IS3. Class 1 integron (Intl1) was most reported to be associated with blaCTX-M-15 (13 studies), with Intl1/dfrA17–aadA5 being the most common gene cassette array. IncFIA-FIB-FII multi-replicons and IncHI2 replicon types were the most common plasmid replicon types that horizontally transfer blaCTX-M-15 gene. Aminoglycoside modifying enzymes, and plasmid-mediated quinolone resistance genes were commonly collocated with blaCTX-M-15 gene on plasmids. This review revealed the predominant role of ISEcp1, Intl1and IncF plasmid in the mobilization and continental dissemination of the blaCTX-M-15 gene in Africa.
ARTICLE | doi:10.20944/preprints201809.0605.v2
Subject: Materials Science, Nanotechnology Keywords: adsorption; 3-Aminopropyltriethoxysilane; carbon dioxide; functionalization; mesoporous silica; MCM-41; SBA-15
Online: 27 December 2018 (05:28:16 CET)
The adsorption of carbon dioxide on amino silanes-functionalized MCM-41 and SBA-15 materials is reported. The functionalization of mesoporous silicas was made by post-synthesis method, by impregnation of 3-aminopropyltriethoxysilane. The obtained materials were characterized by X-ray diffraction, scanning and transmission electron microscopies, nitrogen adsorption-desorption and X-ray photoelectron spectroscopy measurements. The carbon dioxide adsorption capacities for the samples were carried out under ambient pressures. The obtained results evidenced that amino-silanes with a terminal amine (–NH2) were functionalized through covalent coupling of this group on the surface of the channels in the ordered mesoporous silica, meaning that the amine is anchored on the surface of the bigger pores of the MCM-41 and SBA-15 support. For functionalized materials, the CO2 adsorption capacity of the AMCM-41 increased from 0.18 to 1.1 mmol·g−1, whereas for ASBA-15, it was from 0.6 to 1.8 mmol·g−1. The Lagergren kinetic algorithms were applied in order to validate the obtained results, evidencing the enhanced carbon dioxide adsorption capacity and stability of the functionalized ordered mesoporous molecular sieves.
ARTICLE | doi:10.20944/preprints202203.0246.v1
Subject: Life Sciences, Genetics Keywords: entrenchment; protein stability; TEM-1 beta-lactamase; CTX-M-15 beta-lactamase; M182T mutation
Online: 17 March 2022 (08:43:11 CET)
Abstract: Due to their rapid evolution and their impact on health care, be-ta-lactamases, protein degrading beta-lactam antibiotics, are used as generic model of protein evolution. Therefore, we investigated the mutation effects in two distant beta-lactamases TEM-1 and CTX-M-15. Interestingly we found a site with a complex pattern of genetic interactions. Mutation G251W in TEM-1 is in-activating the protein’s function just as the reciprocal mutation W251G in CTXM-15. Phylogenetic analysis revealed that mutation G has been entrenched in TEM-1 background: while rarely observed throughout the phylogeny it is es-sential in TEM-1. Using a rescue experiment in TEM-1 G251W mutant, we could identify sites that alleviates the deviation from G to W. While few of these muta-tions could potentially involve local interactions, most of them were found on distant residues in the 3D structure. Many well-known mutations having an impact on protein stability, such as M182T, were recovered. Our results there-fore suggest that entrenchment of an amino acid may rely on diffuse interactions among multiple sites with a major impact on protein stability.
ARTICLE | doi:10.20944/preprints201809.0271.v1
Subject: Medicine & Pharmacology, Nutrition Keywords: Biomarkers; dietary total fat; pentadecanoic acid; 15:0; heptadecanoic acid; 17:0; odd chain fatty acids.
Online: 15 September 2018 (17:49:08 CEST)
Pentadecanoic acid (C15:0) and heptadecanoic acid (C17:0) have been described as dietary biomarkers of dairy-fat consumption with varying degrees of reliability between studies. It remains unclear how the total amount of dietary fat; one of the main confounding factors in these biomarker investigations, affects C15:0 and C17:0 circulating compositions independently to their relative intake. Additionally, it is unknown how changes in the dietary total-fat affects other fatty acids in circulation. Through two dietary studies with different total-fat levels but maintaining individual fatty acid compositions we were able to see how the dietary total-fat affects the fatty acids in circulation. We saw that there was a significant, proportionate, and robust decrease in the endogenous C15:0 levels with an increase in dietary total-fat. However, there was an increase in the circulating C17:0 compositions as the total-fat increased. To conclude, the dietary total-fat content and fat-type have a very complex influence on the relative compositions of circulating fatty acids, which are independent to the actual dietary fatty acid composition. Knowing how to manipulate circulating C15:0 and C17:0 composition is far-reaching in nutritional/pathological research as they highlight a dietary route to attenuate the development of metabolic disease (both by reducing risk and improving prognosis).
ARTICLE | doi:10.20944/preprints201711.0083.v1
Subject: Materials Science, Polymers & Plastics Keywords: multi-template molecularly imprinted polymers; SBA-15; Panax notoginseng saponins; separation and determination; solid-phase extraction
Online: 14 November 2017 (04:47:13 CET)
The feasible, reliable and selective multi-template molecularly imprinted polymers (MT-MIPs) based on SBA-15 (SBA-15@MT-MIPs) for the selective separation and determination of the trace level of ginsenoside Rb1 (Rb1), ginsenoside Rg1 (Rg1) and notoginsenoside R1 (R1) (Panax notoginseng saponins, PNS) from biological samples were developed. The polymers were constructed by SBA-15 as support, Rb1, Rg1, R1 as multi-template, acrylamide (AM) as functional monomer and ethylene glycol dimethacrylate (EGDMA) as cross-linker. The new synthetic SBA-15@MT-MIPs were satisfactorily applied to solid-phase extraction (SPE) coupled with high performance liquid chromatography (HPLC) for the separation and determination of trace PNS in plasma samples. Under the optimized conditions, the limits of detection (LODs) and quantitation (LOQs) of the proposed method for Rb1, Rg1 and R1 were in the range of 0.63-0.75 ng mL-1 and 2.1-2.5 ng mL-1, respectively. The recoveries of R1, Rb1 and Rg1 were obtained between 93.4% and 104.3% with relative standard deviations (RSDs) in the range of 3.3-4.2%. All results show that the obtained SBA-15@MT-MIPs could be a promising prospect for the practical application in the selective separation and enrichment of trace PNS in the biological samples.
Subject: Engineering, Control & Systems Engineering Keywords: Cooperative Intelligent Transport Systems (CITS); Vehicle to Pedestrian (V2P); Vulnerable 15 Road Users (VRU); GPS; smartphones; Inertial Measurement Units sensors
Online: 6 February 2020 (03:44:08 CET)
The field of Cooperative Intelligent Transport Systems and more specifically Pedestrians to Vehicles could be characterized as quite challenging, since there is a broad research area to be studied, with direct positive results to society. Pedestrians to Vehicles is a type of Cooperative Intelligent Transport System, within the group of Early Warning Collision/Safety System. In this article, we examine the research and applications carried out so far within the field of Pedestrians to Vehicles Cooperative Transport Systems by leveraging the information coming from Vulnerable Road Users’, smartphones. Moreover, an extensive literature review has been carried out in the fields of Vulnerable Road Users Outdoor Localisation via smartphones and Vulnerable Road Users Next Step/Movement Prediction, which are closely related to Pedestrian to Vehicle applications and research. We identify gaps that exist in these fields that could be improved/extended/enhanced or newly developed, while we address future research objectives and methodologies that could support the improvement/development of those identified gaps.
ARTICLE | doi:10.20944/preprints202105.0648.v1
Subject: Biology, Anatomy & Morphology Keywords: herpes simplex virus type 1 (HSV-1); bovine herpesvirus 1 (BoHV-1); Krüppel–like factor 15 (KLF15); infected cell protein 0 (ICP0); BoHV-1 ICP0 (bICP0)
Online: 26 May 2021 (15:10:59 CEST)
Expression of Krüppel–like factor 15 (KLF15), a stress induced transcription factor, is induced during bovine herpesvirus 1 (BoHV-1) reactivation from latency, and KLF15 stimulates BoHV-1 replication. Transient transfection studies revealed KLF15 and glucocorticoid receptor (GR) cooperatively transactivate the BoHV-1 immediate early transcription unit 1 (IEtu1), herpes sim-plex virus type 1 (HSV-1) infected cell protein 0 (ICP0), and ICP4 promoter. The IEtu1 promoter drives expression of bICP0 and bICP4, two key BoHV-1 transcriptional regulatory proteins. Based on these studies, we hypothesized infection is a stressful stimulus that increases KLF15 ex-pression and enhances productive infection. New studies demonstrated that silencing KLF15 impaired HSV-1 productive infection and KLF15 steady state protein levels were increased at late stages of productive infection. KLF15 was primarily localized to the nucleus following in-fection of cultured cells with HSV-1, but not BoHV-1. When cells were transfected with a KLF15 promoter construct and then infected with HSV-1, promoter activity was significantly increased. The ICP0 gene and to a lesser extent bICP0 transactivated the KLF15 promoter in the absence of other viral proteins. In contrast, BoHV-1 or HSV-1 encoded VP16 had no effect on KLF15 pro-moter activity. Collectively, these studies revealed HSV-1 and BoHV-1 productive infection in-creased KLF15 steady state protein levels, which correlated with increased virus production.
ARTICLE | doi:10.20944/preprints202012.0312.v1
Subject: Engineering, Automotive Engineering Keywords: Bayesian Network; Root Cause Analysis; Failure Mode and Effect Analysis; Lithium-Ion 15 Battery Cell; Failure Propagation; Multi-Stage Production; Manufacturing Process; Process Optimization; Scrap Rate
Online: 14 December 2020 (09:31:30 CET)
The production of lithium-ion battery cells is characterized by a high degree of complexit due to numerous cause-effect relationships between process characteristics. Knowledge about the multi-stage production is spread among several experts, rendering tasks such as failure analysis challenging. In this paper, a method is presented, which includes expert knowledge acquisition in production ramp-up by combining Failure Mode and Effects Analysis (FMEA) with a Bayesian Network. We show the effectiveness of this holistic method by building up a large scale, cross-process Bayesian Failure Network in lithium-ion battery production. Using this model, we are able to conduct root cause analyses as well as analyses of failure propagation. The former support operators in identifying root causes once a cell possesses a specific failure by calculating most-probable explanations matched to the individual battery cell data. The latter enable us to analyze propagation of failures and deviations in the production chain and thus provide support for placement of quality gates, leading to a significant reduction in scrap rate. Moreover, it gives an insight into which process steps are key drivers for which final product characteristics.