bluuebunny/crossref_metadata_2025_split huggingface dataset:
Antagonistic pleiotropy and the evolution of extraordinary lifespans in eusocial organisms
Authors: Kreider Jan J. , Pen Ido , Kramer Boris H. 
Published: May 2021

AbstractQueens of eusocial species live extraordinarily long compared to their workers. So far, it has been argued that these lifespan divergences are readily explained by the classical evolutionary theory of ageing. As workers predominantly perform risky tasks, such as foraging and nest defense, and queens stay in the well-protected nests, selection against harmful genetic mutations expressed in old age should be weaker in workers than in queens due to caste differences in extrinsic mortality risk, and thus, lead to the evolution of longer queen and shorter worker lifespans. However, these arguments have not been supported by formal models. Here, we present a model for the evolution of caste-specific ageing in social insects, based on Williams’ antagonistic pleiotropy theory of ageing. In individual-based simulations, we assume that mutations with antagonistic fitness effects can act within castes, that is, mutations in early life are accompanied by an antagonistic effect acting in later life, or between castes, where antagonistic effects emerge due to caste antagonism or indirect genetic effects between castes. In monogynous social insect species with sterile workers, large lifespan divergences between castes evolved under all different scenarios of antagonistic effects, but regardless of the degree of caste-specific extrinsic mortality. Mutations with antagonistic fitness effects within castes reduced lifespans of both castes, while mutations with between-caste antagonistic effects decreased worker lifespans more than queen lifespans, and consequently increased lifespan divergences. Our results challenge the central explanatory role of extrinsic mortality for caste-specific ageing in eusocial organisms and suggest that antagonistic pleiotropy affects castes differently due to reproductive monopolization by queens, hence, reproductive division of labor. Finally, these findings provide new insights into the evolution of tissue-specific ageing in multicellular organisms in general.
Development of a new intermediate‐scale box test on sandwich panel products compared with ISO 13784‐1 room test and EN 13501‐1 classification system
Authors: Yoshioka Hideki , Noguchi Takafumi , Kobayashi Kyoichi , Kanematsu Manabu , Ando Tatsuo , Pareek Sanjay , Hayakawa Tetsuya 
Published: May 2021

SummaryWith respect to the reaction to fire performance of sandwich panel products, in ISO/TC92/SC1/WG7 “Large and intermediate scale fire test methods,” ISO 13784‐1 “Reaction to fire test for sandwich panel building systems—Part 1: Small room test” is specified as a method of test for determining the reaction to fire behavior of sandwich panel building systems. On the other hand, according to EN 13501‐1 “Fire classification of construction products and building elements,” EN 13823 (SBI test) and EN ISO 11925‐2 (ignitability test) are used especially for evaluating the classes B, C, and D in the Euroclass system. The authors have developed a new intermediate‐scale box test for sandwich panel products, pertaining to the correlation with ISO 13784‐1 especially on the flashover occurrence, which was locally standardized as JIS A 1320:2017, and is now internationally being discussed as ISO/WD TS 23657 at ISO/TC92/SC1/WG7. In this paper, regarding five sandwich panel specimens, various fire tests were conducted according to ISO 13784‐1, EN 13501‐1, and ISO/WD TS 23657, and those results were compared with each other, indicating that ISO/WD TS 23657 has a good correlation with ISO 13784‐1 in terms of flashover, and that evaluation results based on ISO/WD TS 23657 could be similar to those based on EN 13501‐1. Furthermore, a new tentative classification system was proposed based on those limited experimental results conducted in this research.
The density paradox: Are densely‐populated regions more vulnerable to Covid‐19?
Authors: Moosa Imad A. , Khatatbeh Ibrahim N. 
Published: May 2021

AbstractThe “density paradox” refers to the observation that some highly populated cities and countries have recorded a smaller number of Covid‐19 cases than regions that are sparsely populated. We present empirical evidence on the role played by population density in spreading the coronavirus, based on cross‐sectional data covering 172 countries (obtained from several sources, including the European Centre for Disease Prevention and Control, the World Bank and the Center for Health Security). The results, obtained by using the techniques of extreme bounds analysis (EBA) and variable addition tests, show that population density has a significantly positive effect on the number of cases but not the number of deaths, as the latter is better explained by measures of preparedness. Plausible explanations are presented for the results to conclude that the “density paradox” is not really a paradox. This paper makes a contribution by shedding more light on a frequently debated issue by using a completely different, and more robust, statistical techniques and by providing results that may be helpful for health and urban planners.
UV filters used in sunscreens—A lack in current coral protection?
Authors: Pawlowski Sascha , Moeller Mareen , Miller Ingo B. , Kellermann Matthias Y. , Schupp Peter J. , Petersen-Thiery Mechtild 
Published: May 2021

Abstract
Ultraviolet (UV) filters used in sunscreens are among the anthropogenic substances that may enter the marine environment by both indirect (via wastewater) and direct pathways (leisure activities). Owing to the recent global decline in coral population, the impact of those UV filters on the coral health is currently under increased investigation. First results from scientists suggest that some of the filters may be toxic to various coral life stages, but an initial cross comparison with existing data from other freshwater organisms does not indicate that corals are specifically more susceptible to UV filters than other standard species. In fact, the available data leading to this conclusion is still vague and based on toxicity and bioaccumulation tests with corals, which are both still at the research stage. To facilitate a proper hazard assessment, robust experimental procedures for coral ecotoxicological studies are considered mandatory. In other words, additional steps should be taken to standardize and validate such new test systems to generate reliable results, which then can be used in regulatory decision making. Furthermore, to facilitate a more detailed and site-specific environmental risk assessment in the marine area, an application-based exposure scenario must be developed. Until these data and tools become available, environmental hazard and risk assessments may be carried out using existing data from freshwater organisms and existing tonnage-based exposure scenarios as a potential surrogate. Integr Environ Assess Manag 2021;17:926–939. © 2021 SETAC
KEY POINTS
UV filters are key ingredients in sunscreens, with a similar function but decidedly different in their physicochemical properties and environmental hazard profiles. Environmental risk assessments of UV filters are currently based on toxicity data from standard test organisms (i.e., algae, Daphnia, fish) and tonnage-based exposure scenarios, making it difficult to assess their impacts on corals. Results indicate that this approach could also safeguard corals, although uncertainty exists linked to data quality and scenarios used. Standardized coral toxicity tests and application-based exposure scenarios would certainly help to clarify existing uncertainties.
An approach for cancer classification using optimization driven deep learning
Authors: Devendran Menaga , Sathya Revathi 
Published: May 2021

AbstractThe normal and cancer cell tissues exhibit different gene expressions. Therefore, gene expression data are the effective source for cancer classification, in which the usage of the original gene expression data is challenging due to their high dimension and small size of the data samples. This article proposes a fractional biogeography‐based optimization‐based deep convolutional neural network (FBBO‐based deep CNN) for cancer classification. The developed FBBO is the integration of the fractional calculus (FC) in the biogeography‐based optimization (BBO), which aims at determining the optimal weights for tuning the deep CNN. Initially, the gene expression data is pre‐processed and subjected to dimensional reduction using the probabilistic principal component analysis (PPCA). The selected features are used for cancer classification enabling a high degree of robustness and accuracy. The experimental analysis using the Colon dataset and Leukemia dataset reveals that the proposed classifier acquired maximal accuracy, sensitivity, specificity, precision, and F‐Measure of 0.98.
Viral Affirmation as Pressure to Perform: Exploring the Role of Affect in Participatory Culture
Authors: Hagge Julia 
Published: May 2021

AbstractAs society becomes increasingly globalized and networked, online participatory cultures provide youth with experiences to foster dispositions and skills required to engage in virtual spaces. This 5‐year longitudinal case study explores the role of affect in the composition practices of an adolescent girl in Scratch, an online programming community. The author applies affect theory to examine why a successful member in a participatory culture would suddenly leave the space where she found success. Findings from this study inform understanding of the role of affect in participatory cultures, including a perceived need to perform. The author provides considerations for literacy educators to foster skills and dispositions necessary for students to engage in sustainable literacy practices in participatory cultures.
Are they ready yet?: A theory‐driven evaluation of suicide risk assessment trainings in psychology graduate programs
Authors: Monahan Maureen F. , Karver Marc S. 
Published: May 2021

AbstractObjectivesThe present study sought to understand the state of suicide risk assessment trainings in clinical psychology graduate programs.MethodsWe surveyed 167 clinical psychology doctoral students' behavioral competency in responding to suicidal clients and their attitudes, perceived behavioral control, subjective norms, and intentions related to suicide risk assessment. Hypotheses were tested using path analysis.ResultsNinety six percent of participants reported receiving some type of suicide risk assessment training at their program. Results provided partial support for significant relationships between attitudes, perceived behavioral control, subjective norms, and intentions. Unexpectedly, amount of training in suicide risk assessments was not related to theory of planned behavior variables including behavioral competency.ConclusionThese findings have implications regarding the effectiveness of current suicide risk assessment training practices and ways to improve trainings to help increase the number of clinical psychologists competent in suicide risk assessment and management.
How did the ancient bacterium, Helicobacter pylori, cause an epidemic of chronic duodenal ulceration?
Authors: Roberts‐Thomson Ian C 
Published: May 2021

AbstractThe association of Helicobacter pylori with chronic duodenal ulceration was a seminal observation in the short history of gastroenterology. However, H. pylori is now known to be an ancient bacterium, whereas there is persuasive evidence that the epidemic of duodenal ulceration began in the second half of the 19th century and continued into the second half of the 20th century. Possible explanations for the epidemic include genomic changes in the organism and environmental or other influences on the human host. While genomic changes resulted in the appearance of virulence factors, these seem likely to have appeared thousands of years ago with minimal effects on gastritis because of coexisting suppression of gastric immunity. In contrast, the emergence of duodenal ulceration is best explained by a change in the pattern of gastritis from inflammation involving the antrum and body in most individuals to a significant minority (10–20%) with antral gastritis but with relative sparing of the body of the stomach. In the latter group, the increase in serum gastrin (particularly G17) associated with antral gastritis had trophic effects on gastric parietal cells with an increase in the parietal cell mass and hypersecretion of gastric acid. Hypersecretion of acid is seen as the major risk factor for duodenal ulceration with significant contributions from environmental factors including smoking and use of nonsteroidal, anti‐inflammatory drugs. Host factors favoring changes in the pattern of gastritis include delayed acquisition of infection and improved nutrition; both with enhancing effects on mucosal immunity.
Altered Functional Connectivity of Hippocampal Subfields in Poststroke Dementia
Authors: Zhao Zhiyong , Cai Huaying , Huang Manli , Zheng Weihao , Liu Tingting , Sun Di , Han Guocan , Ni Linhui , Zhang Yi , Wu Dan 
Published: May 2021

BackgroundThe hippocampus (HP) plays a critical role in memory and orientational functions and is functionally heterogeneous along the longitudinal anterior–posterior axis. Although the previous study has reported volumetric atrophy in hippocampal subfields of patients with poststroke dementia (PSD), how the functional connectivity (FC) is altered in these subfields remains unclear.PurposeTo examine the FC changes of the HP subfields in patients with PSD.Study TypeProspective.PopulationSeventeen normal controls, 20 PSD, and 24 nondemented poststroke (PSND) patients.Field Strength/SequenceA 3.0 T/ T1‐weighted imaging, resting‐state functional and diffusion tensor imaging.AssessmentWe first segmented the HP using independent component analysis, and then used granger causality analysis to calculate the directed FCs (dFCs) between the subfields and the whole brain, and compared the dFCs among PSD, PSND, and controls.Statistical TestsStudent's t‐test, chi‐square test, one‐way ANCOVA, multiple regression, support vector machine, multiple comparison correction, and reproducibility analysis. A P value < 0.05 was considered statistically significant.ResultsOur results showed HP was functionally divided into HPhead, HPbody, and HPtail bilaterally along the longitudinal axis. PSD patients showed significant dementia‐specific decreases in the inward information flow and increases in the outward information flow associated with the bilateral entire HP/HPhead and left HPbody (P < 0.05). Moreover, we observed significant correlations (P < 0.05) between the cognition score and the dFCs related to the bilateral entire HP and left HPhead in the PSD group. Furthermore, dFCs of the HP and its subfields improved the classification between the PSD and PSND patients (accuracy/sensitivity/specificity: 94%/95%/93%) compared to the clinical and demographic parameters alone.Data ConclusionThese findings suggest that altered transmission and reception of information in the HP. These alternations were specific to individual subfields in PSD patients and may offer insight into the neurophysiological mechanisms underlying PSD.Evidence Level1Technical EfficacyStage 2
Optimal design for 1:2n demultiplexer using QCA nanotechnology with energy dissipation analysis
Authors: Sharma Vijay Kumar 
Published: May 2021

AbstractQuantum‐dot cellular automata (QCA) is an emerging technology to design logic circuits at the nanoscale level. It has the potential to replace the complementary metal oxide semiconductor (CMOS) technology. In this paper, an optimal, single layered, single clocked 1:2 demultiplexer (DeMux) circuit is proposed using 19 QCA cells in QCA technology. Proposed 1:2 DeMux circuit is further utilized for designing of 1:4 DeMux and 1:8 DeMux circuits using 72 and 206 QCA cells respectively. DeMux is an important module at the receiver side in the communication system. The performance of the proposed DeMux circuits are checked and compared with the available similar designs using QCA Designer‐E. Proposed 1:2 DeMux decreases 79.17% layout cost and 50% clock latency as compared to the best reported work in the literature. Proposed 1:4 DeMux reduces 48.57% cells count and 40.63% total area while proposed 1:8 DeMux cuts 63.54% cells count and 64.54% total area as compared to best reported similar works in the literature. Energy dissipation pays an important role to design the energy efficient circuits at nanoscale level. Energy dissipations are estimated using QCA Designer‐E and QCA Pro tools. Proposed 1:2 DeMux saves 8.20% total energy dissipation as compared to the existing design.
Comparison of CMIP6 and CMIP5 models in simulating mean and extreme precipitation over East Africa
Authors: Ayugi Brian , Zhihong Jiang , Zhu Huanhuan , Ngoma Hamida , Babaousmail Hassen , Rizwan Karim , Dike Victor 
Published: May 2021

AbstractThis study examines the improvement in Coupled Model Intercomparison Project Phase Six (CMIP6) models against the predecessor CMIP5 in simulating mean and extreme precipitation over the East Africa region. The study compares the climatology of the precipitation indices simulated by the CMIP models with the CHIRPS data set using robust statistical techniques for 1981–2005. The results display the varying performance of the general circulation models (GCMs) in the simulation of annual and seasonal precipitation climatology over the study domain. CMIP6 multi‐model ensemble mean (hereafter MME) shows improved performance in the local annual mean cycle simulation with a better representation of the rainfall within the two peaks, especially the MAM rainfall relative to their predecessor. Moreover, simulation of extreme indices is well captured in CMIP6 models relative to CMIP5. The CMIP6‐MME performed better than the CMIP5‐MME with lesser biases in simulating Simple Daily Intensity Index (SDII), consecutive dry days (CDD), and very heavy precipitation days >20 mm (R20mm) over East Africa. Remarkably, most CMIP6 models are unable to simulate extremely wet days (R95p). Some CMIP6 models (e.g., NorESM2‐MM and CNRM‐CM6‐1) depict robust performance in reproducing the observed indices across all analyses. OND season shows wet biases for some indices (i.e., R95p, PRCPTOT), except for SDII, CDD, and R20mm in CMIP6 models. Consistent with other studies, the mean ensemble performance for both CMIP5/6 shows better performance as compared with individual models due to the cancellation of some systematic errors in the individual models. Generally, CMIP6 depicts improved performance in the simulation of MAM rainfall compared with CMIP5 models. However, the new model generation is still marred by uncertainty, thereby depicting unsatisfactory performance over the East Africa domain. This calls for further investigation into the sources of persistent systematic biases and a methodology for identifying individual models with robust features that can accurately simulate observed patterns for future usage.
Idea Generation, Selection, and Evaluation: A Metacognitive Approach
Authors: Puente‐Díaz Rogelio , Cavazos‐Arroyo Judith , Puerta‐Sierra Lizbeth 
Published: May 2021

AbstractIn the present investigation, we make the claim that the creative process of generating, evaluating, and selecting ideas has cognitive and metacognitive components, capable of influencing each other. Hence, we suggest broadening the scope of creative metacognition. We take an exploratory approach to test relationships between creative beliefs and metacognitive indicators in three studies with business students. Across three studies, overestimation of the quality of one´s ideas and originality scores had a negative relationship with accurate idea selection. Creative self‐efficacy, growth mindsets, and ease of idea generation were positively related to the overestimation of the creativity of ideas generated. In addition, creative self‐efficacy and growth mindsets had a positive relationship with originality scores. We also found some results that were interesting, but inconsistent across all three studies. Ease of idea generation, for example, had a positive relationship with accurate idea selection but a non‐significant relationship in the remaining two studies. Similarly, originality scores significantly informed ease of idea generation in one of three studies. The applied and theoretical implications for creative metacognition were discussed.
Cementocyte alterations associated with experimentally induced cellular cementum apposition in Hyp mice
Authors: Lira dos Santos Elis J. , Salmon Cristiane R. , Chavez Michael B. , de Almeida Amanda B. , Tan Michelle H. , Chu Emily Y. , Sallum Enilson A. , Casati Marcio Z. , Ruiz Karina G. S. , Kantovitz Kamila R. , Foster Brian L. , Nociti Júnior Francisco H. 
Published: May 2021

AbstractBackgroundCellular cementum, a mineralized tissue covering apical tooth roots, grows by apposition to maintain the tooth in its occlusal position. We hypothesized that resident cementocytes would show morphological changes in response to cementum apposition, possibly implicating a role in cementum biology.MethodsMandibular first molars were induced to super‐erupt (EIA) by extraction of maxillary molars, promoting rapid new cementum formation. Tissue and cell responses were analyzed at 6 and/or 21 days post‐procedure (dpp).ResultsHigh‐resolution micro‐computed tomography (micro‐CT) and confocal laser scanning microscopy showed increased cellular cementum by 21 dpp. Transmission electron microscopy (TEM) revealed that cementocytes under EIA were 50% larger than control cells, supported by larger pore sizes detected by micro‐CT. Cementocytes under EIA displayed ultrastructural changes consistent with increased activity, including increased cytoplasm and nuclear size. We applied EIA to Hyp mutant mice, where cementocytes have perilacunar hypomineralization defects, to test cell and tissue responses in an altered mechanoresponsive milieu. Hyp and WT molars displayed similar super‐eruption, with Hyp molars exhibiting 28% increased cellular cementum area versus 22% in WT mice at 21 dpp. Compared to control, Hyp cementocytes featured well‐defined, disperse euchromatin and a thick layer of peripherally condensed heterochromatin in nuclei, indicating cellular activity. Immunohistochemistry (IHC) for cementum markers revealed intense dentin matrix protein‐1 expression and abnormal osteopontin deposition in Hyp mice. Both WT and Hyp cementocytes expressed gap junction protein, connexin 43.ConclusionThis study provides new insights into the EIA model and cementocyte activity in association with new cementum formation.