bluuebunny/crossref_metadata_2025 huggingface dataset:
Students’ Level of Stress as Related to Some Indicators of Lifestyle / Nivo stresa studenata u odnosu na neke pokazatelje životnog stila
Authors: Nešić Milan , Perić Dušan , Srdić Velibor , Muhi Bela
Published: March 2020

A 15-item questionnaire for assessment of stress was applied on a sample of 332 students (age from 19 to 27, 184 males and 148 females). It has been found that over 40% of students have elevated stress levels. The empirical results significantly deviated from the normal distribution. Two groups of participants stood out; the greater group had very elevated levels of stress, while the smaller group had very low average values. When answering questions related to stress, respondents evaluated three elements of lifestyle: the quantity and quality of everyday physical activity, subjective feeling of health and regularity of health checks. Results show that students are not active enough physically and that they rarely check their health. The analysis of variance showed that the highest level of stress is present in students who rated themselves as passive sports lovers, while athletes, amateurs and unexpectedly those who are anti-sports expressed significantly lower levels of stress. Significantly higher levels of stress were present in students who rated their health as poor, while respondents who regularly check their health had the lowest level of stress. Men had higher levels of stress than women.
Teachers Attitudes on Sports Talent in Primary School Pupils Transferring From Class to Subject Teaching / Stavovi nastavnika o sportskoj nadarenosti učenika osnovne škole koji prelaze iz razredne u predmetnu nastavu
Authors: Bajrić Osmo , Goranović Slobodan , Bajrić Senad
Published: March 2020

The study was conducted on a sample of 102 respondents (teachers / professors) employed in the elementary schools of the Zenica-Doboj Canton, Federation of Bosnia and Herzegovina. The main objective of the research is to determine the teachers / professors views on sport talent and any differences in attitudes on the students who pass from class to subject teaching, in activities that engage the student in terms of gender, working status, age and level of education of teachers. The total number of respondents was 102 teachers / professors permanently employed in the elementary school of the Zenica-Doboj Canton of the Federation of BiH.A five-level Likert scale questionnaire was used as a measuring instrument in the research, in which each statement has 5 answers (completely disagree, disagree, don’t have opinion / neutral, agree, completely agree). The questionnaire contains 4 indicators for declaring the sporting talents of children-students, as well as questions related to gender, job / position, age and level of education.LSD Post Hoc tests of success were applied for determination of the statistically significant differences between these group of subjects, the results of the test and analysis of the variation of the different groups.The results obtained indicate that there are no statistically significant differences in the attitudes of teachers / professors or sports talents (above-average achievements) in activities that engage the student in terms of gender, working status, age and level of education.
Obsolescência programada, meio ambiente e políticas públicas
Authors: Boito Francieli , Maia Claudio Machado , Roman Folle Maria Luiza , Bortoletti Everton Gabriel
Published: March 2020

A obsolescência programada é um assunto que tem se mantido em evidência ao longo do tempo. Ela diz respeito à vida útil de produtos tecnológicos e às suas consequências para o meio ambiente. Assim, é através de políticas e outros mecanismos inibidores ou mitigadores que se podem enfrentar seus impactos. Este estudo se debruça sobre a contribuição do Direito Brasileiro no que se refere ao papel das empresas, do poder público e dos indivíduos quanto ao consumo e à troca de produtos. Com base no método dedutivo, ele se vale de uma pesquisa sobre a legislação para o estudo da teoria e o entendimento da doutrina. Os resultados mostram que o assunto ainda é pouco debatido no âmbito jurídico, o que indica a inexistência de impedimentos legais para a poluição do meio ambiente a partir da obsolescência programada. Logo, cabem medidas que combinem a formulação de políticas com o cumprimento da legislação já existente para diminuir o impacto ambiental derivado da obsolescência programada. Com o apoio da cidadania, essas medidas poderiam contemplar tanto o aumento da vida útil dos produtos quanto uma fiscalização mais adequada. Assim, contribuir-se-ia para o tão debatido desenvolvimento sustentável.
Gateway-stable Election Protocol for Heterogeneous Wireless Sensor Network
Authors: Jibreel F. , Daabo M. I. , Gbolagade K. A.
Published: March 2020

An in-depth study of Stable Election Protocol (SEP) revealed that, distance was not considered in selecting the cluster heads in the network. This allows a distant node that is selected as the head to dissipate huge energy in transmitting data to the Base station (BS). It was further observed that, whenever the Base station is relocated outside the field, the energy consumption of the network is high and hence shortening the lifetime of the network. In this paper, a Gateway-SEP protocol is proposed. The G-SEP modified the election probability of electing cluster heads by considering the distance, average distance and residual energy of the advanced nodes. The scheme also introduced a gateway node at the centre of the network and then installed the BS outside the field. Simulation results using MatLab R2017a showed that, the G-SEP performs better than Zonal-Stable Election protocol (ZSEP) in terms of coverage, stability period, throughput and network lifetime.
Estimation of the Future Probable Precipitation based on the Assumption of Non-Stationarity in Seoul
Authors: Jeong Minsu , Lee Taesam , Lee JooHeon , Choi Hyeonseok , Yoon Sunkwon
Published: March 2020

In this study, an estimation of the future probable rainfall in Seoul, Korea, was performed, using non-stationary frequency analysis according to climate change and it was compared with the current probable rainfall. Hourly rainfall data provided by the Korea Meteorological Administration with durations of 1, 2, 3, 6, 12, 24, and 48-h were used as input. For the future projection of precipitation, the RCP 8.5 scenario was selected with the same durations. Moreover, the future hourly rainfall was extracted from using the daily precipitation from 29 Global Climate Models (GCMs), based on the statistical temporal down-scaling method and their corresponding bias corrections. Subsequently, the annual maximum precipitation was extracted for each year. In this study, both stationary and non-stationary frequency analysis was applied based on the observed and predicted time series data sets. In particular, for the non-stationary frequency analysis, the Differential Evolution Markov Chain technique, which combines the Bayesian-based Differential Evolution and Markov chain Monte Carlo methods, was adopted. Finally, the current and future intensity-duration-frequency curves were derived from the optimal probability distribution, and each probable rainfall was estimated. The results of the 29-scenario are presented with quantile estimations. The non-stationary frequency analysis results for Seoul revealed rainfalls of 94.4 mm/h for 30 y, 101.7 mm/h for 50 y, and 111.5 mm/h for 100 y return periods. The average value of the 29-GCM model ensemble was estimated to be approximately 5 mm/h higher than that obtained from the stationary frequency analysis. Considering the changes in hydrological characteristics due to climate change in Seoul, the results of this study could be utilized to pro-actively respond to natural disasters due to such phenomena.
A Study on the Recognition of the Use of Evacuation Equipment and Safety Experience Education
Authors: Lee Jeong Il , Lee Sung Eun
Published: March 2020

This study aims to investigate the degree of recognition of evacuation equipment as well as facilitate the improvement of education. Over 300 specialist groups related to work and education nationwide were selected, without selecting the scope of the region; a questionnaire survey on evacuation equipmentwas conducted. The collected data were analyzed statisticallyusing the SPSS 20.0 program. The questionnaire consisted of general characteristics, knowledge level of evacuation equipment, degree of experience, safety education, educational methods, importance of evacuation equipment, and so on. The results of the questionnaire analysis indicated that, “I very much think so” was most commonly selected for the question “Various types of education in which experiential and theoretical education coexist are necessary.” The analysis showed that evacuation device education obtained through experiential education is suitable once or twice a year or two to three times in three years. It is necessary to make efforts to improve the safety education method for evacuation equipment and the direction of education according to the importance of safety experience education.
Development of Activity Diagrams for Mitigating Large-Scale Disaster Damage During Construction of Underground Urban Utility Tunnels
Authors: Han Yongsik , Song Chang Geun
Published: March 2020

In recent years, demand for utility tunnels in urban underground areas, which accommodate various lifelines such as electric power, communication, water supply, heating, gas, and so on, is increasing. However, unlike domestic manuals that are focused on utility tunnelmaintenance, disaster prevention measures implemented during the construction stage have been institutionalized overseas. In view of this, in order to secure safety related to the construction of utility tunnels in Korea, it is necessary to mitigate large-scale construction disasters that reflect the characteristics of underground urban utility tunnels. In this study, activity diagrams based on crisis warning phases of fire, inundation, and earthquake disasters were created to reduce the damage caused by each disaster. The activity diagrams are expected to contribute to the safety assurance in the event of a large-scale construction disaster during the construction of utility tunnels by effectively and promptly responding to each phase of the disaster.
Determination of the Sensor Placement for Detection Water Quality Problems in Water Supply Systems
Authors: Lee Chan Wook , Lee Yong Jun , Park Ji Seung , Yoo Do Guen
Published: March 2020

The importance of water quality management in pipes has been recently highlighted through the "Red-water phenomenon" in the city of Incheon. This study proposed a methodology for determining the location of measuring instruments during abnormal water quality issues. The proposed method focuses on analyzing the sensitivity of the flow path through a pipe. Additionally, this flow sensitivity through the tube is analyzed by considering both normal and abnormal conditions. The sensitivity of a pipe is the rate at which the water-flow direction changes. Further, a tube with low sensitivity under normal conditions but high sensitivity under abnormal conditions is the pipe for which the instrument should be first installed. The results were analyzed by applying the proposed methodology to a conventional virtual network. It is expected that, in future, the proposed method for determining the location of water quality gauges could be a useful tool for determining the location of instruments during emergencies.
Technical Standard Analysis and Optimal Monitoring Technology to Prevent Ground Subsidence
Authors: Chung Youn-In , Park Won-Joo , Choi Byoung-Il
Published: March 2020

As ground subsidence has recently been gaining public attention, the government (the Ministry of Land, Infrastructure and Transport) as well as local autonomous bodies have recommended preemptive monitoring and have announced a variety of preventive measures against this catastrophic phenomenon. Furthermore, risk factors associated with ground subsidence were identified in a bid to raise awareness regarding the importance of developing preemptive and energy-response technologies (for checking and monitoring underground facilities). Despite the ongoing efforts to reliably detect and identify the condition of buried pipes at home and abroad, very little has been accomplished when it comes to developing technologies for preventing ground subsidence. Therefore, developing new and innovative technologies to (1) inspect and explore water pipes, sewage pipes, and ducts, and (2) to prevent ground subsidence (which has recently become a major threat) in urban areas is crucial. To this end, this study aims to conduct an in-depth analysis on the measurement and exploration criteria and on technical specifications, prior to developing measurement and exploration technologies (as preventive measures against ground subsidence due to damage to water and sewage pipelines). Based on these, the applicability, efficiency, and feasibility of the technologies will be evaluated, and optimal technical specifications will be suggested.
Applying Observed Rainfall and Deep Neural Network for Urban Flood Analysis
Authors: Kim Hyun Il , Lee Jae Young , Han Kun Yeun , Cho Jae Woong
Published: March 2020

Urban flooding primarily occurs due to flash floods in low-lying regions or insufficient capacity of drainage systems. Urban inundation has become more dangerous to residents because of an increase in impermeable areas, uncertainties in urban sewage planning, and the accumulation of sedimentation in drainage pipes. As an urban watershed with a drainage system and an urbanized river is complicated, a specific time interval is required for the preparation and processing of urban runoff analysis. To allow for rapid simulations of urban runoff estimation during heavy rainfall, a deep neural network model that imitates the conditions of a 6-h duration rainfall was developed in this study. Ten different statistical aspects for each rainfall event were considered as input data, and the total accumulated overflow from a manhole was calculated at intervals of 10 min using storm water management model (SWMM). To verify the accuracy of the results from SWMM, the results obtained from a two-dimensional hydraulic model and an inundation trace map were compared. The computational times for the deep neural network and rainfall data-based models proposed in this study were estimated to be within 1 s, whereas the simulation using SWMM required 14 min. The proposed deep learning model was tested using the total accumulated overflow for the rainfall event observed at Gangnam (400) automatic weather station on July 27, 2011. The simulated results agreed with the observed results in terms of the total accumulated discharge.
Real-time Prediction of Urban Inundation based on SWMM 1D-1D Model
Authors: Jang Jong Kyung , Park Min Ki , Lee Na Eun , Lee Jae Min , Yang Dong Min
Published: March 2020

The concept of a Major/Minor system was applied to use urban flood prediction techniques, based on rainfall forecasts and real-time simulations, to reduce flood damage, by notifying a possible flood risk in advance. The SWMM one dimensional (1D)-two dimensional (2D) model has become the standard approach used in urban flood modeling, as it can realistically express the interaction between drainage networks and road surfaces. However, it is limited to the flood analysis of small areas due to its two-dimensional model characteristics, such as its long simulation time. Therefore, the SWMM 1D-1D model, which is fast enough to be applied to real-time simulations, is applied to real-time flood forecasting. To improve the accuracy of the model, SWMM 1D-1D model was calibrated using the SWMM 1D-2D model simulation results, and the SWMM 1D-1D model simulation results were extracted using the SWMM5 DLL and EXCEL VBA to analyze the flood situation. Finally, the applicability of the SWMM 1D-1D model was reviewed based on a rainfall event that occurred on 25 August 2014, assuming an hour of predicted rainfall.
Modeling Nanocarrier Transport across a 3D In Vitro Human Blood‐Brain–Barrier Microvasculature
Authors: Lee Sharon Wei Ling , Campisi Marco , Osaki Tatsuya , Possenti Luca , Mattu Clara , Adriani Giulia , Kamm Roger Dale , Chiono Valeria
Published: March 2020

Polymer nanoparticles (NPs), due to their small size and surface functionalization potential have demonstrated effective drug transport across the blood–brain–barrier (BBB). Currently, the lack of in vitro BBB models that closely recapitulate complex human brain microenvironments contributes to high failure rates of neuropharmaceutical clinical trials. In this work, a previously established microfluidic 3D in vitro human BBB model, formed by the self‐assembly of human‐induced pluripotent stem cell‐derived endothelial cells, primary brain pericytes, and astrocytes in triculture within a 3D fibrin hydrogel is exploited to quantify polymer NP permeability, as a function of size and surface chemistry. Microvasculature are perfused with commercially available 100–400 nm fluorescent polystyrene (PS) NPs, and newly synthesized 100 nm rhodamine‐labeled polyurethane (PU) NPs. Confocal images are taken at different timepoints and computationally analyzed to quantify fluorescence intensity inside/outside the microvasculature, to determine NP spatial distribution and permeability in 3D. Results show similar permeability of PS and PU NPs, which increases after surface‐functionalization with brain‐associated ligand holo‐transferrin. Compared to conventional transwell models, the method enables rapid analysis of NP permeability in a physiologically relevant human BBB set‐up. Therefore, this work demonstrates a new methodology to preclinically assess NP ability to cross the human BBB.
Eco‐Degradable and Flexible Solid‐State Ionic Conductors by Clay‐Nanoconfined DMSO Composites
Authors: Lee Seunghyeon , Hwang Hong Seop , Cho Whirang , Jang Daseul , Eom Taesik , Martin David C. , Wie Jeong Jae , Shim Bong Sup
Published: March 2020

Solid‐state electrolytes can alleviate the safety issues of electrochemical energy systems related to chemical and thermal instabilities of liquid electrolytes. While a liquid provides seamless ionic transport with almost perfect wettability between electrodes, a solid‐state electrolyte needs to demonstrate at least comparable electrochemical performance to liquid electrolytes as well as mechanical robustness and flexibility. Here, the facile preparation of montmorillonite (MMT)/dimethyl sulfoxide (DMSO) nanocomposites is reported, which show high ionic conductivities, mechanical strengths, and thermal stabilities by forming nacre‐mimetic “brick‐and‐mortar” structures. The molecularly confined structures of DMSO are confirmed by X‐ray diffraction peaks with d‐spacings of interplanar spacing that are slightly larger than MMTs. The MMT/DMSO composites have mechanical strengths and toughnesses of 55.3 ± 4.8 MPa and 210.2 ± 32.6 kJ m−2, respectively. The ionic conductivity is ≈2 × 10−4 S cm−1 at room temperature, and their thermal stability is in the range of −100 to 120 °C. The optical translucency, on‐demand eco‐degradability, and solution processability together make the MMT/DMSO composites unique materials with a wide range of solid‐state electrochemical applications including batteries.
Evaluation of biodegradation of polylactic acid mineral composites in composting conditions
Authors: Flynn Allison , Torres Lennard F. , Hart‐Cooper William , McCaffrey Zach , Glenn Gregory M. , Wood Delilah F. , Orts William J.
Published: March 2020

In this study, the enhancement of the biodegradation rate of polylactic acid (PLA) filled with commercially available soil amendment product (NTM) or a nanoclay (Cloisite 25A) were evaluated. Cloisite 25A and NTM were incorporated into PLA at 5, 10, 20 (w/w) through melt blending. Transmission electron micrographs revealed particles with a wide range of sizes that were formed by clumping of many smaller particles. The particles showed good dispersion in PLA by scanning electron microscopy. Under standard composting conditions using a standard technique for aerobic biodegradation of plastic materials, it was shown that the addition of NTM enhanced the biodegradation rate of PLA composites by 3‐ to 4‐fold compared to neat PLA. Linear kinetics were used to obtain induction periods, half‐lives, and rates of mineralization. Finally, mechanical and thermomechanical properties of these blends were compared with PLA. Published 2020. This article is a U.S. Government work and is in the public domain in the USA. J. Appl. Polym. Sci. 2020, 137, 48939.
Silver nanoparticles deposited on polysiloxane networks as active catalysts in dye degradation
Authors: Wójcik‐Bania Monika , Stochmal Edyta , Duraczyńska Dorota
Published: March 2020

The article proposes a new method of obtaining silver nanoparticles on polysiloxane networks using the reducing properties of Si–H groups. Three types of networks with different architecture and distribution of Si–H groups were studied as reducing agents for silver ions and as matrices for the obtained silver nanoparticles. As established by FTIR spectroscopic studies, the redox reaction between Ag+ ions from the silver heptafluorobutyrate solution in toluene and Si–H groups of the networks occurred, which resulted in the appearance of silver nanoparticles in the systems. The amount of metal introduced into individual polysiloxane networks is closely related to the consumption of Si–H groups in them. The type of polysiloxane networks used affects the size of Ag NPs obtained and their distribution on the carrier. Polysiloxane‐Ag systems are observed to be an effective catalyst on reduction of hazardous dye like methyl red, which is confirmed by a decrease in absorbance maximum values.
Small mountain reservoirs in the Alps: New habitats for alpine freshwater biodiversity?
Authors: Fait Pauline , Demierre Eliane , Ilg Christiane , Oertli Beat
Published: March 2020

Today, aquatic biodiversity suffers from many pressures linked to human activities, including climate change, which particularly affects alpine areas. Many alpine freshwater species have shifted their geographical distribution to colder areas, but a reduced availability of suitable habitats is also forecasted. New artificial water bodies could provide habitat enhancement opportunities, including small mountain reservoirs built to overcome a lack of snow during winter.

To investigate the role of reservoirs as a habitat for freshwater invertebrates, a case study was conducted on eight reservoirs in the Swiss Alps. The study aimed to compare the water quality and freshwater biodiversity of the reservoirs with those of 39 natural and newly excavated ponds. Data were collected on physico‐chemistry, freshwater habitat structure, and aquatic insects (dragonflies and aquatic beetles).

The study showed that the mountain reservoirs investigated did not differ from natural ponds in terms of surface area, conductivity, and trophic level. Similarly to natural ponds, reservoirs showed signs of impairment owing to surface run‐off carrying pollutants linked to ski tourism. They presented a low diversity of mesohabitats, and in particular lacked vegetation. Compared with natural ponds, the species richness in reservoirs was lower for dragonflies but not for beetles. At the regional scale, the community from the reservoirs was a subset of the natural ponds community, supporting 38% of the regional species richness for these two insect groups.

The results suggest that mountain reservoirs are likely to be important for biodiversity in alpine areas, both as habitats and as stepping stones for species shifting their geographical range. These water bodies can be enhanced further by some nature‐friendly measures to maximize benefits for biodiversity, including margin revegetation or the creation of adjacent ponds. Ecological engineering needs to be innovative and promote freshwater biodiversity in artificial reservoirs.
The Athena space X‐ray observatory and the astrophysics of hot plasma†
Authors: Barret Didier , Decourchelle Anne , Fabian Andy , Guainazzi Matteo , Nandra Kirpal , Smith Randall , den Herder Jan‐Willem
Published: March 2020

The properties (temperature, density, chemical composition, velocity) of hot astrophysical plasma and the physical processes affecting them (heating/cooling, turbulence, shocks, acceleration) can be probed by high‐resolution X‐ray spectroscopy, to be complemented by high‐spatial‐resolution imaging. The paper presents the status of the European Space Agency's Advanced Telescope for High Energy Astrophysics (Athena) mission, particularly focusing on the science performance of its two focal‐plane instruments for studies of extended X‐ray sources: the wide‐field imager and the X‐ray integral field unit. This paper then provides a brief summary of the breakthroughs expected with Athena on the astrophysics of hot plasma, building on the vast heritage of the discoveries and revolutionary results obtained by Chandra and XMM‐Newton in this field. As of November 12, 2019, Athena successfully concluded its feasibility study, and has since then moved into the definition phase, with a launch date scheduled in the early 2030s.
Examining the legacy of the Warnock Report in Northern Ireland: A Foucauldian genealogical approach
Authors: Purdy Noel , Hunter John , Totton Lois
Published: March 2020

Over 40 years after the publication of the Report of the Committee of Enquiry into the Education of Handicapped Children and Young People, commonly referred to as the Warnock Report, this article uniquely considers its legacy in the context of Northern Ireland. The article adopts a Foucauldian genealogical approach to consider first the specific context of the ‘emergence’ or ‘origins’ of the Warnock Report in the 1970s, highlighting competing political forces and the positioning of the report at the very end of the age of post‐war welfarism. The approach details the key elements of the Warnock Report itself, and then charts the resulting development of SEN policy in Northern Ireland, culminating in the faltering process of reform which began in 2006 and has been partially completed but which has recently been halted by the collapse of the power‐sharing Executive and the suspension of the Northern Ireland Assembly in January 2017. The legacy of the Warnock Report is critically examined, identifying the main positive contributions of the report but also acknowledging the enduring challenges set against a complex current financial and political context. Finally, rather than leaving Warnock completely behind, a case is made for a fresh, detailed, context‐specific reading of this seminal report.
RXRα and MRTF‐A have a synergistic effect in the retinoic acid‐induced neural‐like differentiation of adult bone marrow‐derived mesenchymal stem cells
Authors: Luo Ying , Liang Chen , Liu Yu , Liu Xiaopeng , Xu Yao
Published: March 2020

Mesenchymal stem cells (MSCs) have multilineage differentiation potential and can transform into neuron cells under an appropriate environment. Retinoic acid (RA) facilitates the neuronal differentiation of MSCs. We found that RXRα, a RA receptor, was significantly upregulated in RA‐induced process. Here, we show that RXRα collaborated with myocardin‐related transcription factor‐A (MRTF‐A) to strongly promote the RA‐induced process as evidenced by the increase in NF‐H expression and NF‐H promoter transcription activity. Our studies reveal that RXRα and MRTF‐A exhibit protein interactions and synergistically inhibit the MSCs apoptosis by enhancing the P21 expression. Furthermore, RXRα and MRTF‐A can activate P21 transcription by affecting the formation of the MRTF‐A/RXRα/RARE complex. These findings reveal the important roles of RXRα and MRTF‐A signaling in RA‐induced neural‐like differentiation of MSCs and describe a new mechanism underlying the synergistic interaction of RXRα and MRTF‐A.
Nachhaltig Kosten sparen bei O‐Ringen
Authors: Richter Bernhard , Blobner Ulrich ,   O‐Ring Prüflabor Richter
Published: March 2020

Wer die Entwicklungen der Dichtungstechnik kennt, versteht warum ein u.U. sinkender Beschaffungspreis für O‐Ringe nur ein untergeordneter Aspekt ist.
A framework for automated and objective modification of tubular structures: Application to the internal carotid artery
Authors: Bergersen Aslak W. , Kjeldsberg Henrik A. , Valen‐Sendstad Kristian
Published: March 2020

Patient‐specific medical image‐based computational fluid dynamics has been widely used to reveal fundamental insight into mechanisms of cardiovascular disease, for instance, correlating morphology to adverse vascular remodeling. However, segmentation of medical images is laborious, error‐prone, and a bottleneck in the development of large databases that are needed to capture the natural variability in morphology. Instead, idealized models, where morphological features are parameterized, have been used to investigate the correlation with flow features, but at the cost of limited understanding of the complexity of cardiovascular flows. To combine the advantages of both approaches, we developed a tool that preserves the patient‐specificness inherent in medical images while allowing for parametric alteration of the morphology. In our open‐source framework morphMan we convert the segmented surface to a Voronoi diagram, modify the diagram to change the morphological features of interest, and then convert back to a new surface. In this paper, we present algorithms for modifying bifurcation angles, location of branches, cross‐sectional area, vessel curvature, shape of bends, and surface roughness. We show qualitative and quantitative validation of the algorithms, performing with an accuracy exceeding 97% in general, and proof‐of‐concept on combining the tool with computational fluid dynamics. By combining morphMan with appropriate clinical measurements, one could explore the morphological parameter space and resulting hemodynamic response using only a handful of segmented surfaces, effectively minimizing the main bottleneck in image‐based computational fluid dynamics.
Lessons and recommendations from three decades as an NSF REU site: A call for systems‐based assessment
Authors: McDevitt Andrew L. , Patel Manisha V. , Ellison Aaron M.
Published: March 2020

For more than 30 years, the US National Science Foundation's Research Experiences for Undergraduates (REU) program has supported thousands of undergraduate researchers annually and provides many students with their first research experiences in field ecology or evolution. REUs embed students in scientific communities where they apprentice with experienced researchers, build networks with their peers, and help students understand research cultures and how to work within them. REUs are thought to provide formative experiences for developing researchers that differ from experiences in a college classrooms, laboratories, or field trips. REU assessments have improved through time but they are largely ungrounded in educational theory. Thus, evaluation of long‐term impacts of REUs remains limited and best practices for using REUs to enhance student learning are repeatedly re‐invented. We describe how one sociocultural learning framework, cultural–historical activity theory (CHAT), could be used to guide data collection to characterize the effects of REU programs on participant's learning in an educationally meaningful context. CHAT embodies a systems approach to assessment that accounts for social and cultural factors that influence learning. We illustrate how CHAT has guided assessment of the Harvard Forest Summer Research Program in Ecology (HF‐SRPE), one of the longest‐running REU sites in the United States. Characterizing HF‐SRPE using CHAT helped formalize thoughts and language for the program evaluation, reflect on potential barriers to success, identify assessment priorities, and revealed important oversights in data collection.
STOP floxing around: Specificity and leakiness of inducible Cre/loxP systems
Authors: Stifter Sebastian A. , Greter Melanie
Published: March 2020

Cre and CreER mouse strains are powerful tools that have proven invaluable for investigating the function of genes and for the fate‐mapping of cell populations. The fidelity of these systems however are becoming more and more contested. In this issue of the European Journal of Immunology, Van Hove et al. and Chappell‐Maor et al. carefully dissect the cellular specificities of two commonly used CreER mouse strains for the study of CNS macrophages; Cx3cr1CreER and Sall1CreER. Both studies elegantly highlight that CreER strains, as well as the "floxed" allele to be targeted, need to be carefully selected and properly characterized in order to ensure reproducible and robust data and interpretations. These studies are a cautionary tale for this technology, but also highlight that we must continuously question and improve our experimental approaches.
An artificial accelerogram generator code written in Matlab
Authors: Ferreira Fernando , Moutinho Carlos , Cunha Álvaro , Caetano Elsa
Published: March 2020

Artificial accelerograms are a very useful tool for designing structures against seismic hazards; in particular, when structures exhibit nonlinear behavior. This paper presents a Matlab code for generating artificial accelerograms to match code‐defined spectra based on the modification of actual earthquake ground motions. In this case, while the code is written to generate Eurocode 8‐compatible accelerograms, it can be easily adapted to any other code in the world. The proposed code determines the earthquake spectra and Fourier Transform using the Fast Fourier Transform algorithm and then modifies the Fourier Transform in order to match the predefined spectra. The code also includes instructions for outlining different actual ground motions, soil, and earthquake type. The code is geared to students and researchers in the field of Structural and Earthquake Engineering. The objective of this work is to provide a Matlab code that can be integrated in other research programs such as seismic structural analysis, structural control software, or other codes.
Nanodiamond‐Based Separators for Supercapacitors Realized on Paper Substrates
Authors: Polino Giuseppina , Scaramella Alessandro , Manca Valerio , Palmieri Elena , Tamburri Emanuela , Orlanducci Silvia , Brunetti Francesca
Published: March 2020

In response to the request for sustainable high performance energy storage devices, a significant interest is focused on developing environmentally friendly supercapacitors. In this context, cellulose‐based substrates for energy storage devices can be well‐engineered, lightweight, safe, thin, and flexible. Herein, a scalable, low‐cost, and easy‐to‐process approach for the preparation of supercapacitors using large area techniques like spray and blade coating is presented. Following a green strategy, all components are chosen or formulated in water‐based dispersions. Symmetric supercapacitors using common copy paper and electronic paper as the substrate, and poly(3,4‐ethylenedioxythiophene)‐poly(styrenesulfonate) (PEDOT:PSS) as electrodes, are realized and investigated. The novelty of this work consists of the use of composites based on detonation nanodiamonds (DNDs) and hydroxypropyl cellulose (HPC) as a solid‐state electrolyte and separator. Devices with solution electrolyte using the same HPC + DND composite but with the addition of sodium sulfate are prepared. The performance obtained using solid electrolyte (HPC + DNDs) and liquid electrolyte (HPC + DNDs + Na2SO4) on both substrates is comparable in terms of specific capacitance: ≈0.13 – 0.52 F g−1for (HPC + DNDs) and ≈0.35 – 0.82 F g−1for (HPC + DNDs + Na2SO4), with power density in the range of ≈19 – 24 μW cm−2.
Data dissemination for Internet of vehicle based on 5G communications: A survey
Authors: Benalia Elhadja , Bitam Salim , Mellouk Abdelhamid
Published: March 2020

With the increase of the number of connected vehicles on roads, the data dissemination within traditional network suffers from many limitations like high latency, a significant amount of dropped packets and network congestion. Therefore, the Internet of vehicles (IoV) has been designed as an emerging paradigm that combines the intelligent transportation system (ITS) with Internet of Things (IoT) technology. IoV allows vehicles to exchange data with its surroundings in order to enhance the traffic safety and to provide digital services to road users. In this paper, a taxonomy of data dissemination protocols proposed for IoV is surveyed according to three main categories namely, the smart control‐based category, social networks‐based category, and traditional approaches. We also review the data dissemination in IoV based on the fifth generation (5G) communications with emphasis on enabling technologies, architectures, services, and challenges. Moreover, we suggest in this study a new generic 5G‐based IoV architecture named IoVs based on fifth generation communications to enhance data dissemination by the promising and efficient transmission technologies such as fifth‐generation network properties, software‐defined network functionalities (SDN), and cloud‐fog computing services. The proposed scheme helps to meet challenges in the low latency, high reliability and security, high performance, mobility contrary to conventional architectures.
Experimental Investigation of In‐plane Performance Variation on Anode Supported Solid Oxide Fuel Cells Using Segmented Cathodes and Reference Electrodes
Authors: Kim M. W. , Son M. J. , Park H. , Park J.‐Y. , Lim H.‐T.
Published: March 2020

In this study, planar anode‐supported solid oxide fuel cells (5 × 5 cm2) were fabricated with cathode segmentations and tested in a channel type setup. The in‐plane performance variation became significant with an increasing current density (fuel utilization), and impedance analysis on each segment indicated that the poor performance in the outlet region was due to gas conversion overpotential combined with gas concentration overpotential. Pt reference electrodes were embedded in the electrolyte layers of the segments so that the anode and cathode overpotential could be separated for each segment. It was found that the cathode overpotential was dominant for both segments, which suggested that the cathode overpotential determined the overall cell performance. On the other hand, the anode overpotential was responsible for the in‐plane performance variation. Post‐analysis revealed that the Ni anode was partially oxidized and its layer was delaminated in the outlet region. Thus, this study suggests that the anode overpotential related to gas conversion is a critical factor in determining Ni anode stability as well as overall cell performance in planar anode supported cells with a gas channel setup.
Can conditional cash transfers improve maternal health care? Evidence from El Salvador's Comunidades Solidarias Rurales program
Authors: de Brauw Alan , Peterman Amber
Published: March 2020

There is growing evidence on positive human capital impacts of large, poverty‐focused cash transfer programs. However, evidence is inconclusive on whether cash transfer programs affect maternal health outcomes, and if so, through which pathways. We use a regression discontinuity design with an implicit threshold to evaluate the impact of Comunidades Solidarias Rurales in El Salvador on four maternal health service utilization outcomes: (a) prenatal care; (b) skilled attendance at birth; (c) birth in health facilities; and (d) postnatal care. We find robust impacts on outcomes at the time of birth but not on prenatal and postnatal care. In addition to income effects, supply‐side health service improvements and gains in women's agency may have played a role in realizing these gains. With growing inequalities in maternal health outcomes globally, results contribute to an understanding of how financial incentives can address health systems and financial barriers that prevent poor women from seeking and receiving care at critical periods for both maternal and infant health.
Resolving a puzzling anomaly in the spin‐coupled generalized valence bond description of benzene
Authors: Xu Lu T. , Cooper David L. , Dunning Thom H.
Published: March 2020

In an earlier study of benzene, Small and Head‐Gordon found that the spin‐coupled generalized valence bond (SCGVB) wave function for the π system predicted a distorted (non‐D6h) geometry, one with alternating CC bond lengths. However, the variations in the energy were very small and the predictions were made using a very small basis set (STO‐3G). We re‐examined this prediction using a much larger basis set (aug‐cc‐pVTZ) to determine the dependence of the energy of benzene on the distortion angle, ΔθCXC (ΔθCXC = 0° corresponds to the D6h structure). We also found a distorted geometry with the optimum ΔθCXC being 0.31° with an energy 0.040 kcal mol−1 lower than that for the D6h structure. In the optimum geometry, adjacent CC bond lengths are 1.3861 Å and 1.4004 Å. Analysis of the SCGVB wave function led us to conclude that the cause of the unusual non‐D6h geometry predicted by the SCGVB calculations seems to be a result of the interaction between the Kekulé and Dewar components of the full SCGVB wave function. The addition of doubly ionic configurations to the SCGVB wave function leads to the prediction of a D6h geometry for benzene and a dependence on ΔθCXC essentially the same as that predicted by the complete active space self‐consistent field wave function.
Family health history collected by virtual conversational agents: An empirical study to investigate the efficacy of this approach
Authors: Ponathil Amal , Ozkan Firat , Welch Brandon , Bertrand Jeffrey , Chalil Madathil Kapil
Published: March 2020

Family health history (FHx) is one of the simplest and most cost‐effective and efficient ways to collect health information that could help diagnose and treat genetic diseases at an early stage. This study evaluated the efficacy of collecting such family health histories through a virtual conversational agent (VCA) interface, a new method for collecting this information. Standard and VCA interfaces for FHx collection were investigated with 50 participants, recruited via email and word of mouth, using a within‐subject experimental design with the order of the interfaces randomized and counterbalanced. Interface workload, usability, preference, and satisfaction were assessed using the NASA Task Load Index workload instrument, the IBM Computer System Usability Questionnaire, and a brief questionnaire derived from the Technology Acceptance Model. The researchers also recorded the number of errors and the total task completion time. It was found that the completion times for 2 of the 5 tasks were shorter for the VCA interface than for the standard one, but the overall completion time was longer (17 min 44 s vs. 16 min 51 s, p = .019). We also found the overall workload to be significantly lower (34.32 vs. 42.64, p = .003) for the VCA interface, and usability metrics including overall satisfaction (5.62 vs. 4.72, p < .001), system usefulness (5.76 vs. 4.84, p = .001), information quality (5.43 vs. 4.62, p < .001), and interface quality (5.66 vs. 4.64, p < .001) to be significantly higher for this interface as well. Approximately 3 out of 4 participants preferred the VCA interface to the standard one. Although the overall time taken was slightly longer than with standard interface, the VCA interface was rated significantly better across all other measures and was preferred by the participants. These findings demonstrate the advantages of an innovative VCA interface for collecting FHx, validating the efficacy of using VCAs to collect complex patient‐specific data in health care.
Ultrarapid iron polymaltose infusion for iron deficiency anaemia: a pilot safety study
Authors: Banakh Iouri , Turek Martha , Chin Jong , Churchill Travis
Published: March 2020

Treatment of iron deficiency is often achieved via single administration of intravenous iron polymaltose (IP) as a prolonged infusion or multiple infusions of more rapidly administered products. This study examined the safety of IP for total body iron replacement administered as ultrarapid infusions. A prospective open‐label cohort pilot study was conducted at a tertiary centre to investigate IP infusions with doses up to 500–1500 mg administered over 30 or 15 min (10 patients in each group). Adverse effects were graded as mild, moderate or severe, with monitoring during the infusion and a 1‐week follow‐up period. Three patients in each group experienced four mild adverse effects during the infusion. During the follow‐up period, two participants in each group experienced adverse effects, with one in each group experiencing a moderate adverse effect requiring treatment with paracetamol. In this pilot study, the safety outcomes of ultrarapid infusions were similar to both 4‐ and 1‐h infusions of iron polymaltose and to ferric carboxymaltose. Fully powered studies of ultrarapid iron polymaltose are warranted given the safety results of this study.
Simple thin layer chromatography–ultraviolet spectrophotometric method for quality assessment of binary fixed‐dose‐combinations of lamivudine/tenofovir disoproxil fumarate and lamivudine/zidovudine in tablet formulations
Authors: Vaikosen Edebi N. , Kashimawo Adesegun J. , Soyinka Julius O. , Orubu Samuel , Elei Simeon , Ebeshi Benjamin U.
Published: March 2020

Antiretroviral fixed‐dose‐combination drugs are best assayed with high‐performance liquid chromatography, or liquid chromatography–tandem mass spectrometry. However, most scientists in developing nations have no access to these expensive instruments. A more affordable quantitative technique is the use of ultraviolet–visible spectroscopy—where often the absorption spectra of these antiretrovirals are overlapping; thus complex derivative methodologies are required for quantification. A simple, rapid, and accurate thin layer chromatography–ultraviolet spectrophotometric method for the quantification of binary mixtures of lamivudine, zidovudine, and tenofovir–disoproxil–fumarate in tablet formulations was developed. Lamivudine/tenofovir–disoproxil–fumarate and lamivudine/zidovudine were extracted and separated on glass thin‐layer chromatography plates. Drugs were identified in ultraviolet light at 254 nm and quantified in acidic medium using ultraviolet spectrophotometry. The retardation factors were 0.43, 0.79, and 0.81 for lamivudine, tenofovir–disoproxil–fumarate, and zidovudine, respectively, with corresponding absorption maxima at 270, 260, and 265 nm. Linearity ranged from 1 to 40 µg/mL for all drugs (R = 0.9998–0.9999), while recovery studies were 95.10–102.11% and amount in formulations ranged from 97.99 ± 0.63 to 101.47 ± 2.39%. The paired t‐test (n = 5) indicated no significant difference between the proposed and high‐performance liquid chromatography methods, hence comparable and can be used as an alternative method in routine quality determination of antiretroviral medicines.
Investigation of mass transfer properties and kinetic performance of high‐efficiency columns packed with C18 sub‐2 μm fully and superficially porous particles
Authors: Felletti Simona , De Luca Chiara , Lievore Giulio , Pasti Luisa , Chenet Tatiana , Mazzoccanti Giulia , Gasparrini Francesco , Cavazzini Alberto , Catani Martina
Published: March 2020

Three columns packed with 2.0 μm superficially porous particles, 1.7 μm fully porous particles, and monodisperse 1.9 μm fully porous particles with narrow particle size distribution have been deeply characterized from a kinetic point of view. The 1.9 μm column showed excellent kinetic performance, comparable to that of the superficially porous one. These two columns also exhibit flatter c‐branches of the van Deemter curve compared to the 1.7 μm fully porous particles column, resulting in smaller loss of efficiency when they are operated at higher flow rates than the optimal ones. The independent evaluation of each contribution to band broadening has revealed that the difference in kinetic performance comes from the very small eddy dispersion contribution on the 1.9 μm column, surprisingly even lower than that of the superficially porous one. This finding suggests a very good packing of the monodisperse 1.9 μm column. On the other hand, the potential of 1.7 μm fully porous particles is completely broken down by the strong frictional heating effect already arising at relatively low flow rates.