bluuebunny/crossref_metadata_2025_split huggingface dataset:
Many-body effects of Cu-Phthalocyanine crystal for Solar Cell application
Authors: Lawal Abdullahi , Koma Ahmed Musa , Godfrey Lawissense Dunah 
Published: May 2021

Abstract
Performance of organic semiconductor material is very sensitive to the reactivity of electrical and optical properties. Structural properties of Cu-Phthalocyanine molecular crystal (β-CuPc) are studied via first-principles approach within density functional theory (DFT) framework. The calculated structural parameters are close to experimental result. Many-body perturbation theory (MBPT) based on convolution of non-interacting Green’s function (G0) and a screened Coulomb interaction (W0), G0W0 approximation were used for quasiparticle (QP) band structure and optical properties calculations. The bandgap value of 1.71 eV calculated with G0W0+RPA is in good agreement with experimental value. Optical properties calculations show that the results obtained within G0W0 plus random phase approximation (RPA) are close to available experimental results. Interestingly, optical gap of 1.71 eV and strong absorption of β-CuPc in the visible light and ultraviolet regions shows that the investigated material is suitable for optoelectronic and solar cells applications.
Optical and Morphological Properties of Electrodeposited Thin Films of ZnS
Authors: Madugu M.L. , Lawal Abdullahi , Ndahi H.M. 
Published: May 2021

AbstractZinc sulphide (ZnS) thin films were grown on glass/fluorine-doped tin oxide (FTO) substrates using the simple and inexpensive electrodeposition technique. The deposition electrolytic bath was prepared from aqueous acidic solution of ZnSO4and (NH4)2S2O3. The work was carried out to investigate the optical and morphological properties of ZnS layers. The deposition temperature and the pH values were respectively 30°C and 1.50. It was observed that optical properties vary with variation in growth voltage. It was observed that bandgap decrease with increase in growth voltage since the higher the growth voltage, the higher the current density. As the deposition temperature in increased, the bandgap is seen to decrease. After annealing, the bandgaps are seen to increase and the absorption edges can be seen to have smoothened out. Increase in annealing temperature play a significant role in achieving desired results especially when it is meant for device application. As expected, the layer thickness is seen to increase with increase in deposition temperature.
Enhancement of the performance of ZnO based natural dye sensitized solar cells via PVA morphology controlled nanorods
Authors: Offiah S U , Agbo S N , Ezema C G , Ugwuoke P E , Ekwealor A B C , Agbogu A N C , Ezekoye B A , Ezema F I 
Published: May 2021

Abstract
ZnO nanoparticles were synthesized via low temperature hydrothermal synthesis procedures at 90 °C using zinc nitrate hexahydrate as the zinc oxide precursors and hexamethyleneamine as the precipitating agent. The structural, surface morphology and optical studies of the hydrothermally synthesized ZnO nanoparticles revealed that the synthesized products were nano-rods, grown in very high-density with well-crystalline wurtzite hexagonal phase and good optical properties. Ployvinyl alcohol (PVA) was used as surfactant to modify the surface features of the ZnO nanorods. The ZnO nano-rods were employed as photo-anode for dye sensitized solar cell (DSSC) and were sensitized by natural dye extracted from Baphia nitida plant. The photovoltaic characteristics of the cell such as the short circuit current, open circuit voltage as well as the shunt and series resistances of the cell were studied. The incident photon to current conversion efficiency was also studied. The study revealed that the PVA improved the overall photo-conversion efficiency of the DSSC.
Perceived Role of Extension Education in Promoting the Use of Biogas for Sustainable Agricultural Development in Nigeria
Authors: Igwe N J , Ogwo U , Abbah O I 
Published: May 2021

Abstract
Biomass technology is a renewable energy source that is significantly used for cooking and heating, which when explored can reduce the use of fossil fuel. This study investigated the perceived role of extension education in promoting biomass technology for sustainable agriculture development in Nigeria. The study adopted the descriptive survey research design. Data were collected from 268 registered members of All Nigeria Farmers Association, Nsukka; and 22 Agriculture extension agents in Nsukka Local Government Area. Researchers-designed questionnaire which was validated by three experts was used for data collection. Mean and standard deviation were used for data analysis. Findings showed that sensitization of farmers on acceptability of use of farm wastes for biogas production; dissemination of information on renewable energy techniques to the farmers and sensitization of farmers on use of farm wastes for biogas production are perceived roles of extension education in promoting the use of farm wastes for renewable energy. Other perceived roles reported by the respondents include motivation of farmers on issues of renewable energy and provision of energy management advice to the farmers. The researchers recommended that efforts should be made to create awareness among the farmers on the use of farm wastes for biogas for renewable energy.
Influence of Rim Angles and Heat flux Distribution Boundary on the Heat Transfer of an Absorber Tube for a Parabolic Trough Solar Collector
Authors: Francis Okafor I. 
Published: May 2021

Abstract
One of the most important solar concentrator among other concentrating collectors is the parabolic trough solar collector because of its successful application in solar electricity generation. This study investigated the influence of collector rim angles and non-uniform heat flux distribution boundaries on the inner heat transfer coefficients of an absorber tube for a parabolic trough solar collector. Laminar flow steady-state condition was considered where buoyancy effects were significant. Numerical simulation was conducted in ANSYS Fluent version 14.5. Sinusoidal non-uniform heat flux distributions boundary conditions were implemented via a user defined function in Fluent. It was established that the absorber tube-wall temperature rise with a rise in the collector rim angle and the circumferential span of non-uniform heat flux allocations limit. It was furthermore revealed that when buoyancy-driven secondary flow is present, the internal heat transfer coefficient increased more than twice advanced than the pure forced-convection case (i.e. no buoyancy effects), and representing heat transfer improvement due to secondary flow effects. Also, when buoyancy effects are present, the mean internal heat transfer coefficient improved as the heat flux intensity is increased, the collector rim direction and the circumferential span of the non-uniform heat flux distributions boundary. This study further discovered that the mean internal heat transfer coefficient became higher with a rise in the temperature of the absorber tube inlet flowing fluid.
An examination of sedation requirements and practices for mechanically ventilated critically ill patients with COVID-19
Authors: Balakrishna Aditi , Walsh Elisa C , Hamidi Arzo , Berg Sheri , Austin Daniel , Pino Richard M , Hanidziar Dusan , Chang Marvin G , Bittner Edward A 
Published: May 2021

AbstractPurposePreliminary reports suggest that critically ill patients with coronavirus disease 2019 (COVID-19) infection requiring mechanical ventilation may have markedly increased sedation needs compared with critically ill, mechanically ventilated patients without COVID-19. We conducted a study to examine sedative use for this patient population within multiple intensive care units (ICUs) of a large academic medical center.MethodsA retrospective, single-center cohort study of sedation practices for critically ill patients with COVID-19 during the first 10 days of mechanical ventilation was conducted in 8 ICUs at Massachusetts General Hospital, Boston, MA. The study population was a sequential cohort of 86 critically ill, mechanically ventilated patients with COVID-19. Data characterizing the sedative medications, doses, drug combinations, and duration of administration were collected daily and compared to published recommendations for sedation of critically ill patients without COVID-19. The associations between drug doses, number of drugs administered, baseline patient characteristics, and inflammatory markers were investigated.ResultsAmong the study cohort, propofol and hydromorphone were the most common initial drug combination, with these medications being used on a given day in up to 100% and 88% of patients, respectively. The doses of sedative and analgesic infusions increased for patients over the first 10 days, reaching or exceeding the upper limits of published dosage guidelines for propofol (48% of patients), dexmedetomidine (29%), midazolam (7.7%), ketamine (32%), and hydromorphone (38%). The number of sedative and analgesic agents simultaneously administered increased over time for each patient, with more than 50% of patients requiring 3 or more agents by day 2. Compared with patients requiring 3 or fewer agents, patients requiring more than 3 agents were of younger age, had an increased body mass index, had increased serum ferritin and lactate dehydrogenase concentrations, had a lower Pao2:Fio2 (ratio of arterial partial pressure of oxygen to fraction of inspired oxygen), and were more likely to receive neuromuscular blockade.ConclusionOur study confirmed the clinical impression of elevated sedative use in critically ill, mechanically ventilated patients with COVID-19 relative to guideline-recommended sedation practices in other critically ill populations.
ProtCHOIR: a tool for proteome-scale generation of homo-oligomers
Authors: Torres Pedro H M , Rossi Artur D , Blundell Tom L 
Published: May 2021

Abstract
The rapid developments in gene sequencing technologies achieved in the recent decades, along with the expansion of knowledge on the three-dimensional structures of proteins, have enabled the construction of proteome-scale databases of protein models such as the Genome3D and ModBase. Nevertheless, although gene products are usually expressed as individual polypeptide chains, most biological processes are associated with either transient or stable oligomerisation. In the PDB databank, for example, ~40% of the deposited structures contain at least one homo-oligomeric interface. Unfortunately, databases of protein models are generally devoid of multimeric structures. To tackle this particular issue, we have developed ProtCHOIR, a tool that is able to generate homo-oligomeric structures in an automated fashion, providing detailed information for the input protein and output complex. ProtCHOIR requires input of either a sequence or a protomeric structure that is queried against a pre-constructed local database of homo-oligomeric structures, then extensively analyzed using well-established tools such as PSI-Blast, MAFFT, PISA and Molprobity. Finally, MODELLER is employed to achieve the construction of the homo-oligomers. The output complex is thoroughly analyzed taking into account its stereochemical quality, interfacial stabilities, hydrophobicity and conservation profile. All these data are then summarized in a user-friendly HTML report that can be saved or printed as a PDF file. The software is easily parallelizable and also outputs a comma-separated file with summary statistics that can straightforwardly be concatenated as a spreadsheet-like document for large-scale data analyses. As a proof-of-concept, we built oligomeric models for the Mabellini Mycobacterium abscessus structural proteome database. ProtCHOIR can be run as a web-service and the code can be obtained free-of-charge at http://lmdm.biof.ufrj.br/protchoir.
Evolutionary, proteomic, and experimental investigations suggest the extracellular matrix of cumulus cells mediates fertilization outcomes†
Authors: Keeble Sara , Firman Renée C , Sarver Brice A J , Clark Nathan L , Simmons Leigh W , Dean Matthew D 
Published: May 2021

AbstractStudies of fertilization biology often focus on sperm and egg interactions. However, before gametes interact, mammalian sperm must pass through the cumulus layer; in mice, this consists of several thousand cells tightly glued together with hyaluronic acid and other proteins. To better understand the role of cumulus cells and their extracellular matrix, we perform proteomic experiments on cumulus oophorus complexes (COCs) in house mice (Mus musculus), producing over 24,000 mass spectra to identify 711 proteins. Seven proteins known to stabilize hyaluronic acid and the extracellular matrix were especially abundant (using spectral counts as an indirect proxy for abundance). Through comparative evolutionary analyses, we show that three of these evolve rapidly, a classic signature of genes that influence fertilization rate. Some of the selected sites overlap regions of the protein known to impact function. In a follow-up experiment, we compared COCs from females raised in two different social environments. Female mice raised in the presence of multiple males produced COCs that were smaller and more resistant to dissociation by hyaluronidase compared to females raised in the presence of a single male, consistent with a previous study that demonstrated such females produced COCs that were more resistant to fertilization. Although cumulus cells are often thought of as enhancers of fertilization, our evolutionary, proteomic, and experimental investigations implicate their extracellular matrix as a potential mediator of fertilization outcomes.
Developing Reading Skills in Prelingually Deaf Preschool Children: Fingerspelling as a Strategy to Promote Orthographic Learning
Authors: Miller Paul , Banado-Aviran Efrat , Hetzroni Orit E 
Published: May 2021

Abstract
The aim of this study was to clarify whether fingerspelling provides a sophisticated mechanism that promotes the development of detailed orthographic knowledge for deaf individuals even in the absence of paralleling phonological knowledge. An intervention program comprised of various procedures chaining between fingerspelled sequences; their written correlates and meaning were administered in a multiple probe single-subject research design across semantic categories to four children with severe to profound prelingual hearing loss (age 4.2–6 years). Results demonstrate the occurrence of rapid orthographic learning during intervention and reliable retention of it in maintenance checks, despite the participants’ insufficiently developed phonological skills. Observations of the participants’ behavior further suggest fingerspelling to function as an effective mediator in the initial development of robust detailed orthographic lexicon. Analyzes also indicate that “learning through action” and “relevance to the task” provide two key factors in relation to the promotion of orthographic learning, with their absence creating an obvious vacuum in this regard. Insights from the study are discussed with reference to their implication for the development of learning materials and learning environments for prelingually deaf and other novice learners.
SATB2 Defect Promotes Colitis and Colitis-associated Colorectal Cancer by Impairing Cl-/HCO3- Exchange and Homeostasis of Gut Microbiota
Authors: Ni Hengli , Chen Yongyu , Xia Wei , Wang Chuyi , Hu Caihong , Sun Lina , Tang Wen , Cui Hongxia , Shen Tong , Liu Yao , Li Jianming 
Published: May 2021

Abstract

Background
SATB2 is a diagnostic biomarker and a favourable prognostic marker for colorectal cancer [CRC], but its role in colitis and colitis-associated colorectal cancer [CAC] is unknown.

Methods
Colitis was induced in intestinal epithelial-specific Satb2 knockout [Satb2 IEC-KO] and control mice using dextran sulphate sodium [DSS]. RNA-seq analysis was performed on colonic tissues, and 16S rDNA-Seq on faecal bacterial DNA from Satb2 IEC-KO and control mice. Immunohistochemistry and flow cytometry were performed to reveal the proportions of different immune cells. Chromatin immunoprecipitation [ChIP] and luciferase reporter were applied to show the regulatory role of SATB2 on SLC26A3, of which the Cl-/HCO3- exchange activity was measured fluorometrically by the pHi-sensitive dye. Bacteroides were detected by fluorescence in situ hybridisation [FISH] on colonic tissue.

Results
Satb2 IEC-KO mice suffered from intestinal epithelial damage spontaneously, and developed more severe colitis and CAC. The expression of SLC26A3 correlated well with SATB2 revealed by RNA-seq and The Cancer Genome Atlas [TCGA] data, and was governed by SATB2 confirmed by ChIP and luciferase reporter experiments. Decreased intestinal flora diversity was seen in Satb2 IEC-KO mice. Bacteroides were more abundant and could colonise into the inner layer of colonic mucosa in Satb2 IEC-KO mice. Faecal microbiome transplantation from Satb2 IEC-KO mice aggravated colitis and M1 macrophages infiltration.

Conclusions
SATB2 plays a vital role in maintaining intestinal homeostasis, and its deficiency promotes the development of colitis and CAC by influencing the intestinal luminal environment and gut flora.
Weighted multichannel singular spectrum analysis for post-processing GRACE monthly gravity field models by considering the formal errors
Authors: Shen Yunzhong , Wang Fengwei , Chen Qiujie 
Published: May 2021

SUMMARY
Gravity Recovery and Climate Experiment (GRACE) Spherical Harmonics (SH) solutions are usually provided together with the corresponding formal errors, however, all multichannel singular spectrum analysis (MSSA) approaches neglect the formal errors of SH coefficients in processing the GRACE time-series. In this contribution, we propose a weighted MSSA to directly process the incomplete time-series of GRACE monthly gravity models by taking the formal errors into account. A 14-yr time-series of Release 06 (RL06) monthly gravity field models from the Center for Space Research (CSR) truncated to degree and order 60 for the period April 2002 to August 2016 is analysed by weighted MSSA, the results are compared with those from the improved MSSA that directly processes the incomplete time-series without considering the formal errors. The first 10 principal components derived by using the weighted MSSA can capture the variance in total up to 82.05 per cent, higher than 80.19 per cent by the improved MSSA. All the fitting errors of GRACE SH coefficients by the weighted MSSA are smaller than those by the improved MSSA, which indicates that weighted MSSA can extract more geophysical signals than the improved MSSA approach. To evaluate the efficiency of the weighted MSSA to eliminate noise, the ratios of the latitude weighted RMS of signals over lands and oceans are computed. Based on all the available months of GRACE solutions, the mean RMS ratio of signals over lands relative to oceans derived by the weighted MSSA is 5.04, higher than 4.96 by the improved MSSA. Therefore, we can conclude that the proposed weighted MSSA can suppress noise more efficiently and extract more geophysical signals from the GRACE time-series, which highlights the necessity of considering formal errors and the effectiveness of the weighted MSSA in post-processing the GRACE monthly gravity field models.
Dancing in the Rain: How Do Abiotic Conditions Influence Sexually Selected Behaviors in the White-Ruffed Manakin?
Authors: Shogren Elsie H , Jones Megan A , Boyle W Alice 
Published: May 2021

SynopsisTropical animals respond to rainfall in population-specific ways. In extremely wet regions, endotherms experience heavy rains as stressors with consequences for behavior and demography. Ultimately, such stressors can affect the relative strength of abiotic selection, reducing the scope for sexual selection, and other biotic sources of selection. We studied population-level differences in the response to rainfall of White-ruffed manakins (Corapipo altera) on the Caribbean slope of Costa Rica, a species having a lek mating system subject to strong sexual selection. Between 2008 and 2013, we studied reproductive behavior in a population inhabiting an extremely wet site; estimates of apparent survival were low, and the turnover of display courts and dominant males was high. Males also engaged in coordinated display, and sub-adult males practiced in the presence of adults. Over three breeding seasons (2017–2019), we studied a population of the same species at a site only 110 km away, but in a location receiving roughly half as much rain. We tested behavioral predictions of three alternative mechanisms—indirect abiotic effects, direct mortality effects, and direct behavioral effects—linking rainfall to sexual selection in these two populations. Data derived from over 4300 h of observations at 105 display sites revealed high interannual variation in nearly all response variables, including turnover of display sites, retention of alpha status, male display behavior, and time females spent assessing male display. Additionally, we detected spatial differences in drivers of display site turnover. Notably, age distribution of males was skewed toward older individuals at the drier location. Based on these findings, we infer that indirect abiotic effects on forest structure leading to display site transience and direct effects of mortality increasing turnover in the male population likely underlie links between rain and the spatial and temporal differences we documented. Our results are consistent with rain constituting an important source of abiotic selection for tropical endotherms and modulating the scope for sexual selection near the extremes of a species’ hygric niche.
Shared Gaze Visualizations in Collaborative Interactions: Past, Present and Future
Authors: D’Angelo Sarah , Schneider Bertrand 
Published: May 2021

AbstractThe past decade has witnessed a growing interest for using dual eye tracking to understand and support remote collaboration, especially with studies that have established the benefits of displaying gaze information for small groups. While this line of work is promising, we lack a consistent framework that researchers can use to organize and categorize studies on the effect of shared gaze on social interactions. There exists a wide variety of terminology and methods for describing attentional alignment; researchers have used diverse techniques for designing gaze visualizations. The settings studied range from real-time peer collaboration to asynchronous viewing of eye-tracking video of an expert providing explanations. There has not been a conscious effort to synthesize and understand how these different approaches, techniques and applications impact the effectiveness of shared gaze visualizations (SGVs). In this paper, we summarize the related literature and the benefits of SGVs for collaboration, describe important terminology as well as appropriate measures for the dual eye-tracking space and discuss promising directions for future research. As eye-tracking technology becomes more ubiquitous, there is pressing need to develop a consistent approach to evaluation and design of SGVs. The present paper makes a first and significant step in this direction.