bluuebunny/crossref_metadata_2025 huggingface dataset:
MIMO CPW-Fed Bent Antenna Based USB Dongle for ECMA-368 WPANs
Authors: Beddiafi Y. , Abed D. , Boualleg A. , Mehallel E.
Published: December 2021

A multiple-input-multiple-output (MIMO) ultra-wideband (UWB ) printed bent antenna, suitable for MB-OFDM ECMA-368 system integration with the wireless universal serial-bus (WUSB) dongle is proposed. The antenna consists of two antenna elements with an overall area of 18 X 53 mm2. Each antenna element is a simple modified folded-monopole fed by a coplanar waveguide (CPW). The design process of proposed MIMO UWB CPW-fed bent antenna configuration is presented in four simple steps. Experimental results show that the proposed design has a good impedance bandwidth in the range of 2.95–18.55 GHz with 147.2% fractional bandwidth (FBW). Moreover, the proposed antenna enjoys, low envelope correlation coefficient (ECC), good diversity gain (DG), low total active reflection coefficient (TARC) and omnidirectional radiation patterns. The bit error rate (BER) of the overall MB-OFDM ECMA-368 system with the existence of the proposed MIMO UWB CPW-fed bent antenna is evaluated in more realistic transmission channel scenario by using the extracted transmitting and receiving UWB antennas transfer functions.
Person image generation through graph-based and appearance-decomposed generative adversarial network
Authors: He Yuling , Zhao Yingding , Yang Wenji , Xu Yilu
Published: December 2021

Due to the sophisticated entanglements for non-rigid deformation, generating person images from source pose to target pose is a challenging work. In this paper, we present a novel framework to generate person images with shape consistency and appearance consistency. The proposed framework leverages the graph network to infer the global relationship of source pose and target pose in a graph for better pose transfer. Moreover, we decompose the source image into different attributes (e.g., hair, clothes, pants and shoes) and combine them with the pose coding through operation method to generate a more realistic person image. We adopt an alternate updating strategy to promote mutual guidance between pose modules and appearance modules for better person image quality. Qualitative and quantitative experiments were carried out on the DeepFashion dateset. The efficacy of the presented framework are verified.
Adversarial example defense based on image reconstruction
Authors: Zhang Yu(AUST) , Xu Huan , Pei Chengfei , Yang Gaoming
Published: December 2021

The rapid development of deep neural networks (DNN) has promoted the widespread application of image recognition, natural language processing, and autonomous driving. However, DNN is vulnerable to adversarial examples, such as an input sample with imperceptible perturbation which can easily invalidate the DNN and even deliberately modify the classification results. Therefore, this article proposes a preprocessing defense framework based on image compression reconstruction to achieve adversarial example defense. Firstly, the defense framework performs pixel depth compression on the input image based on the sensitivity of the adversarial example to eliminate adversarial perturbations. Secondly, we use the super-resolution image reconstruction network to restore the image quality and then map the adversarial example to the clean image. Therefore, there is no need to modify the network structure of the classifier model, and it can be easily combined with other defense methods. Finally, we evaluate the algorithm with MNIST, Fashion-MNIST, and CIFAR-10 datasets; the experimental results show that our approach outperforms current techniques in the task of defending against adversarial example attacks.
Molecular genetic diversity of seaweeds morphologically related to Ulva rigida at three sites along the French Atlantic coast
Authors: Dartois Manon , Pante Eric , Viricel Amélia , Becquet Vanessa , Sauriau Pierre-Guy
Published: December 2021

Foliose species of the genus Ulva are notoriously difficult to identify due to their variable morphological characteristics and high phenotypic plasticity. We reassessed the taxonomic status of several distromatic foliose Ulva spp., morphologically related to Ulva rigida, using DNA barcoding with the chloroplastic tufA and rbcL (for a subset of taxa) genes for 339 selected attached Ulva specimens collected from three intertidal rocky sites. Two of the collection sites were in Brittany and one site was in Vendée, along the Atlantic coast of France. Molecular analyses included several museum specimens and the holotype of Ulva armoricana Dion, Reviers & Coat. We identified five different tufA haplotypes using a combination of phylogenetic analysis, with the support of several recently sequenced holotypes and lectotypes, and a species delimitation method based on hierarchical clustering. Four haplotypes were supported by validly named species: Ulva australis Areschoug, Ulva fenestrata Postels & Ruprecht, Ulva lacinulata (Kützing) Wittrock and U. rigida C. Agardh. The later was additionally investigated using rbcL. The fifth haplotype represented exact sequence matches to an unnamed species from European Atlantic coasts. Our results support: (1) the synonymy of both U. rigida sensu Bliding non C. Agardh and U. armoricana with U. lacinulata. This finding is based on current genetic analysis of tufA from the U. armoricana holotype and recent molecular characterization of the lectotype of U. laetevirens, which is synonymous to U. australis, (2) the presence of U. australis as a misidentified introduced species in Brittany, and (3) the presence of U. fenestrata and U. rigida in southern Brittany. The taxonomic history of each species is discussed, highlighting issues within distromatic foliose taxa of the genus Ulva and the need to genetically characterize all its available type specimens.
Macrophage immunomodulatory activity of Acanthopanax senticousus polysaccharide nanoemulsion via activation of P65/JNK/ikkαsignaling pathway and regulation of Th1/Th2 Cytokines
Authors: Li Xianghui , Zhang Zhiqiang , Guo Zhenhuan , Zhao Li , Liu Yonglu , Ma Xia , He Qigai
Published: December 2021

Nanoemulsions (NE) are used widely in pharmaceutical drug formulations and vaccine preparation, and Acanthopanax senticousus polysaccharide (ASPS) is a natural bioactive compound with immunostimulatory activity. Therefore, NE-loaded ASPS is expected to provide immunological enhancement for effective treatment. In the present study, Acanthopanax senticousus polysaccharide (ASPS was encapsulated into nanoemulsions, the resultant ASPS–NE were coated with a negative charge, and the immune enhancement mechanism of these ASPS-NE formulations was analyzed. The immunosuppressive animal models (70 ICR mice, male) for the study were established using cyclophosphamide. In addition, the activation of splenocyte proliferation, phagocytosis of the macrophages, the ratio of CD4+ to CD8+, the concentrations of the cytokines in serum, Western blot analysis was used for the analysis of the P65/JNK/ikk α signaling pathway in the peritoneal macrophage s. The results revealed that the ASPS-NE could stimulated the proliferation of splenocytes and enhance immunity. The ASPS-NE induced the expression of different cytokines (TNF-α, IFN-γ, IL-2, and IL-6), could activate the expressions of P65, JNK, and ikkα, and regulated the Th1/Th2 cytokines. These findings demonstrated the potential of ASPS-NE formulations for drug delivery and to induce potent and sustained immune responses.
Integrated analysis and the identification of a circRNA-miRNA-mRNA network in the progression of abdominal aortic aneurysm
Authors: Si Ke , Lu Da , Tian Jianbo
Published: December 2021

Background

Abdominal aortic aneurysm (AAA) is a disease commonly seen in the elderly. The aneurysm diameter increases yearly, and the larger the AAA the higher the risk of rupture, increasing the risk of death. However, there are no current effective interventions in the early stages of AAA.

Methods

Four gene expression profiling datasets, including 23 normal artery (NOR) tissue samples and 97 AAA tissue samples, were integrated in order to explore potential molecular biological targets for early intervention. After preprocessing, differentially expressed genes (DEGs) between AAA and NOR were identified using LIMMA package. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis were conducted using the DAVID database. The protein-protein interaction network was constructed and hub genes were identified using the STRING database and plugins in Cytoscape. A circular RNA (circRNA) profile of four NOR tissues versus four AAA tissues was then reanalyzed. A circRNA-miRNA-mRNA interaction network was constructed after predictions were made using the Targetscan and Circinteractome databases.

Results

A total of 440 DEGs (263 up-regulated and 177 down-regulated) were identified in the AAA group, compared with the NOR group. The majority were associated with the extracellular matrix, tumor necrosis factor-α, and transforming growth factor-β. Ten hub gene-encoded proteins (namely IL6, RPS27A, JUN, UBC, UBA52, FOS, IL1B, MMP9, SPP1 and CCL2) coupled with a higher degree of connectivity hub were identified after protein‐protein interaction network analysis. Our results, in combination with the results of previous studies revealed that miR-635, miR-527, miR-520h, miR-938 and miR-518a-5p may be affected by circ_0005073 and impact the expression of hub genes such as CCL2, SPP1 and UBA52. The miR-1206 may also be affected by circ_0090069 and impact RPS27A expression.

Conclusions

This circRNA-miRNA-mRNA network may perform critical roles in AAA and may be a novel target for early intervention.
Spatiotemporal patterns of the COVID-19 epidemic in Mexico at the municipality level
Authors: Mas Jean-François , Pérez-Vega Azucena
Published: December 2021

In recent history, Coronavirus Disease 2019 (COVID-19) is one of the worst infectious disease outbreaks affecting humanity. The World Health Organization has defined the outbreak of COVID-19 as a pandemic, and the massive growth of the number of infected cases in a short time has caused enormous pressure on medical systems. Mexico surpassed 3.7 million confirmed infections and 285,000 deaths on October 23, 2021. We analysed the spatio-temporal patterns of the COVID-19 epidemic in Mexico using the georeferenced confirmed cases aggregated at the municipality level. We computed weekly Moran’s I index to assess spatial autocorrelation over time and identify clusters of the disease using the “flexibly shaped spatial scan” approach. Finally, we compared Euclidean, cost, resistance distances and gravitational model to select the best-suited approach to predict inter-municipality contagion. We found that COVID-19 pandemic in Mexico is characterised by clusters evolving in space and time as parallel epidemics. The gravitational distance was the best model to predict newly infected municipalities though the predictive power was relatively low and varied over time. This study helps us understand the spread of the epidemic over the Mexican territory and gives insights to model and predict the epidemic behaviour.
Climate modulates grazing effects on primary productivity of arid ecosystems in Argentina
Authors: Calvo Dianela Alejandra , Peter Guadalupe , Gaitán Juan José
Published: December 2021

La introducción de fuentes de agua artificiales para uso ganadero en ecosistemas donde el agua ha estado ausente durante su evolución ha provocado cambios en la vegetación. Se ha demostrado que existe una atenuación radial del impacto del pastoreo con la distancia a la fuente de agua, favoreciendo la formación de piósferas. En Argentina, no existen estudios que evalúen cómo actúa el clima como modulador de los efectos del pastoreo en piósferas a lo largo de gradientes ambientales. El objetivo de este estudio fue evaluar y analizar el rol que juega el clima como modulador de los efectos que el pastoreo induce a escala local. Esto permitiría comprender como actúa el clima sobre los efectos del pastoreo. Para ello se seleccionaron 77 piósferas a lo largo de un gradiente climático y se analizó la variabilidad espacial de los valores de NDVI (Índice de Vegetación de la Diferencia Normalizada) en el gradiente de pastoreo y su relación con la precipitación media anual y la temperatura media anual. Se observaron dos patrones diferentes de respuesta del NDVI. El patrón 1 presentó un aumento del NDVI con la distancia al punto de agua, mientras que el patrón 2 manifestó un comportamiento inverso. Las piósferas de los patrones 1 y 2 se ubicaron por encima y por debajo de los 280 mm de precipitación anual y de los 14.5 °C de temperatura media anual, respectivamente. Estos resultados sugieren que existe un comportamiento diferencial de la vegetación frente al pastoreo que estaría modulado por variables climáticas.
Temporal variations on NDVI predict temporal changes in vegetation cover across Patagonian drylands (Argentina)
Authors: Gaitan Juan , Ciano Nicolas , Oliva Gabriel , Bran Donaldo , Butti Lucas , Cariac Germán , Caruso Cecilia , Opazo Walter , Ferrante Daniela , Echevarria Daniela , Buono Gustavo , Fantozzi Anabella , Guirado Emilio , Maestre Fernando T.
Published: December 2021

La variación temporal del índice NDVI predice los cambios temporales de la cobertura vegetal en las tierras secas de la Patagonia argentina. En las tierras secas, la vegetación natural es una fuente importante de sustento para las comunidades que viven en ellas, dado que la utilizan como alimento, combustible y forraje para el ganado. Además de los bienes y servicios que brinda a las comunidades, la vegetación de las tierras secas también juega un papel importante en muchos procesos ecosistémicos, como por ejemplo el reciclaje de nutrientes o la protección del suelo frente a la erosión. Por lo tanto, el monitoreo a largo plazo de la cobertura vegetal es clave para la toma de decisiones en la gestión de estas regiones. En este estudio, analizamos la variación de la cobertura vegetal en 239 sitios de una red de monitoreo a largo plazo (red MARAS), en uno de los biomas de tierras secas más grandes del mundo: la estepa patagónica argentina. A continuación, la relacionamos con la variación de diferentes períodos del Índice de Vegetación de Diferencia Normalizada (Normalized Difference Vegetation Index, NDVI), obtenido del sensor MODIS, que sirve como variable predictora. El modelo empírico ajustado explicó hasta un 40% de la variación en la cobertura vegetal medida a campo. Con este sencillo modelo empírico hemos estimado y cartografiado los cambios temporales en la cobertura vegetal de un extenso bioma de tierras secas a bajo coste.
Soil biodiversity and organic carbon are essential to reverse desertification
Authors: Muñoz-Rojas Miriam , Delgado-Baquerizo Manuel , Lucas-Borja Manuel Esteban
Published: December 2021

La biodiversidad y el carbono orgánico del suelo, así como la interacción entre ambos, juegan papeles esenciales en el mantenimiento y regulación de los servicios ecosistémicos de las zonas secas, desde la fertilidad del suelo a la producción de alimentos. El cambio climático y los impactos antrópicos pueden provocar pérdidas en la biodiversidad y carbono del suelo, lo cual puede resultar en alteraciones de los ciclos del carbono y la funcionalidad de los ecosistemas derivando en procesos acelerados de desertificación. Es necesario, por tanto, mejorar nuestro conocimiento sobre la compleja diversidad biológica del suelo, así como su interacción con el carbono orgánico en las zonas secas. Esto nos permitirá diseñar estrategias efectivas para promover el secuestro de carbono en el suelo, contribuyendo así a revertir los procesos de degradación y desertificación. En esta revisión discutimos la importancia de la biodiversidad y el carbono orgánico del suelo de las zonas secas en un contexto de cambio global, definiendo la relación entre ambos y su respuesta a factores climáticos y degradación. También destacamos el uso de herramientas avanzadas tales como la genómica, y practicas relevantes de manejo del suelo que nos permitan incrementar los contenidos de carbono y mejorar la diversidad y funcionalidad de suelo en las zonas secas, con el fin último de prevenir y revertir la desertificación.
Water and Sustainability. Towards a water transition in Iberian South-East
Authors: Martínez Fernández Julia , Esteve Selma Miguel Angel , Zuluaga Guerra Paula Andrea
Published: December 2021

Aunque suele asociarse desertificación con aridez y erosión del suelo, múltiples estudios en el ámbito mediterráneo han demostrado que en el medio natural las tasas de erosión son bajas, incluso con vegetación escasa. Por otra parte, las zonas áridas albergan una biodiversidad singular y paisajes de gran interés, por lo que algunas constituyen espacios protegidos. En realidad, los procesos que más contribuyen a la degradación y pérdida de productividad natural en ámbitos mediterráneos, especialmente en zonas áridas, son los cambios de uso del suelo, en particular la expansión del regadío, el cual provoca un aumento de las demandas hídricas por encima de los recursos disponibles, generando sobreexplotación de acuíferos y pérdida de manantiales y humedales y su biodiversidad asociada. Los casos analizados en el Sureste Ibérico a dos escalas, local (Mazarrón y Águilas) y de cuenca (cuenca del Segura), muestran cómo la introducción de recursos hídricos externos, con independencia de la eficiencia en su uso, no reduce la sobreexplotación hídrica por la dinámica que se establece entre recursos y demandas, conocida como espiral de insostenibilidad, la cual presenta claras concomitancias con el síndrome general de desertificación. Además, la expansión del regadío en zonas áridas está afectando a ecosistemas que mantenían un buen estado de conservación y una biodiversidad singular ligada a la aridez. Se requiere una transición hídrica que reduzca las demandas hídricas en zonas áridas, lo que incluye la reducción de la superficie de regadío en las zonas en las que ha aumentado por encima de lo sostenible.
Burden of Multidrug Resistant Escherichia coli among Patients with Urinary Tract Infections in a Tertiary Care Centre- A Retrospective Analysis
Authors: Ramakrishna Manjula Sidlagatta , Abimannan Gomathi Chitra , Jeyamani Lavanya , Ramalingam Aparna , Anbalagan Karthik
Published: December 2021

Introduction: Multidrug Resistant (MDR) Escherichia coli isolates causing Urinary Tract Infections (UTIs), capable of producing Extended Spectrum Beta Lactamase (ESBL), AmpC beta lactamase and resistance to carbapenems pose serious challenges to the clinicians causing worse clinical scenarios. The detection of these isolates has prime importance in infection control and improving therapeuticmanagementofpatients,astheirprevalenceisincreasing worldwide. Injudicious use of antibiotics has led to selective pressure, resulting in the emergence of antibiotic resistance in gram negative bacteria globally. This rise in antimicrobial resistance has decreased the options for empirical therapy, causing a global health concern in infections associated with ESBL producing and AmpC producing isolates. Aim: To investigate the burden of ESBL producing, AmpC beta-lactamase producing, carbapenem resistant, and MDR Escherichia coli isolated from urine samples in a tertiary care centre. Materials and Methods: The present retrospective study conducted from January to December 2019. A total of 10,535 urine samples were received during the study period, to find out the burden of drug resistant Escherichia coli isolates in urine samples, analyse their antibiogram and patients’ socio-demographic information. Records of microscopic observations to antibiogram of each isolate was noted down from the register for urine samples, and further analysed. The data was coded, verified, entered and analysed using Statistical Package for Social Sciences (SPSS) version 18.0. Results: Among the total urine samples (10,535), 1434 (13.6%) Escherichia coli isolates were identified, of which 553 (38.6%) were found to be ESBL producing, 497 (34.6%) AmpC beta- lactamase producing, 172 (12%) Carbapenem resistant, and 765 (53.3%) MDR. Majority of the isolates were from the age group of 51-60 years 288 (20.08%). The least susceptibility of the isolates was detected against penicillin G 1410 (98.3%), followed by ampicillin 1160 (80.9%) and cephazolin 74 (67.9%). Among the MDR isolates, the maximum drug resistance (398, 52%) was seen in penicillin, cephems, quinolones and Folate pathway antagonist group of antimicrobials. Conclusion: Identification of the drug resistant isolates is of high priority and crucial for therapeutic management of the patients, and infection control. Stringent antimicrobial stewardship policies and judicious use of antimicrobials can decrease the spread of antimicrobial resistant genes in the hospital environment.
Extraction Free Rapid Detection of SARS-CoV-2 from Oropharyngeal/Nasopharyngeal Swabs by Real Time PCR
Authors: Sinha Parul , Gupta Sandeep , Gupta Megha , Jain Dinesh Kumar , Sharma Malvika , Sharma Kanika , Hooja Saroj , Vyas Nitya
Published: December 2021

Introduction: The emergence of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) pandemic has been troublesome particularly for developing countries that lack infrastructure and capacities to produce the kits locally. Simplification of the method can increase diagnostic efficiency which can benefit patients and help in infection control, consequently saving time and lives. Aim: To evaluate the diagnostic value of four methods (that omit extraction step) for detection of SARS-CoV-2 against the traditional extraction method. Materials and Methods: This was a cross-sectional analysis for evaluating diagnostic accuracy of four methods for detection of SARS-CoV-2 by real-time Reverse Transcriptase Polymerase Chain Reaction (rRT-PCR), conducted in the Department of Microbiology, SMS Medical College, Jaipur, Rajasthan, India, in October 2020. Ninety four SARS-CoV-2 RT-PCR positive samples and 20 negative samples were taken for this study. Automated extraction system was used for Ribonucleic Acid (RNA) extraction and four different approaches were compared to the traditional extraction method for detection of SARS-CoV-2 by RT-PCR. Data was entered and analysed using Statistical Package for the Social Sciences (SPSS) statistical software version 24.0. Results: The automated RNA extraction method was compared to the method of direct addition of samples with (Heat processed Direct Viral transport medium Sample (HDVS)) and without heating (Direct Viral transport medium Sample (DVS)), directs addition of diluted (1:5) sample with (Heat processed diluted VTM sample (HdVS)) and without heating (Diluted VTM sample (dVS)) as well as after addition of Proteinse K (PK) to the diluted samples that came either negative/invalid. Out of four methods, the HdVS method gave the best results, considering extraction with Perkin Elmer as standard, this method showed sensitivity of 96.74%, specificity of 100%. Conclusion: In current pandemic, molecular testing is critically challenged by the limited supplies of reagents of nucleic acid extraction alternative method like diluting and heating of Viral Transport Media (VTM) samples and using them directly as elutes serve as an easy, fast and inexpensive alternative.
Assessing the Impact of Strategic Management Practices on the Performance of Commercial Banks in Makurdi – Nigeria
Authors: Kuhe David Adugh , Utor Victor , Ikyanyon Darius
Published: December 2021

The aim of this study is to assess the impact of strategic management practices on the performance of some commercial banks in Makurdi – Nigeria. The study utilized primary data obtained through structured questionnaire administered to 160 respondents sampled from seven commercial banks in the study area. The collected data from the study were analyzed using descriptive statistics, percentages, correlation and regression analysis. The correlation results showed that strategic management practices are highly positively and significantly related to organizational performance. The regression result which explains about 99.9% variability in the model revealed that strategic management had positive and significant impact on the performance and profitability of commercial banks. The study recommended among other things that the management of the commercial banks should enhance the strategic management techniques in order to improve performance.
An Improved Rasa for Load Balancing in Cloud Computing
Authors: Olufunminiyi Oyekanmi Ezekiel , Perpetual Oladoja  Ilobekemen , Oluwatosin Omotehinwa Temidayo
Published: December 2021

Cloud is specifically known to have difficulty in managing resource usage during task scheduling, this is an innate from distributed computing and virtualization. The common issue in cloud is load balancing management. This issue is more prominent in virtualization technology and it affects cloud providers in term of resource utilization and cost and to the users in term of Quality of Service (QoS). Efficient procedures are therefore necessary to achieve maximum resource utilization at a minimized cost. This study implemented a load balancing scheme called Improved Resource Aware Scheduling Algorithm (I-RASA) for resource provisioning to cloud users on a pay-as-you-go basis using CloudSim 3.0.3 package tool. I-RASA was compared with recent load balancing algorithms and the result shown in performance evaluation section of this paper is better than Max-min and RASA load balancing techniques. However, it sometimes outperforms or on equal balance with Improved Max-Min load balancing technique when using makespan, flow time, throughput, and resource utilization as the performance metrics.
Biology Education in Perspective: An Inquiry into Ghanaian Senior High School Students’ Attitude Towards Biology Practical Lessons
Authors: Tordzro Godwin , Asamoah Evans , Ofori Kennedy Nyeseh
Published: December 2021

This study aimed at finding out the attitude of students towards Biology practical lessons in selected Senior High Schools in Ghana. The study adopted the descriptive sample design, involving both quantitative and qualitative research approaches. The population of the study comprised 408 students and 24 teachers. The students and teachers were chosen at random from a table of random numbers respectively. Data was collected using informal observation, questionnaire and documents. The questionnaire was made up of both open and close-ended questions. The Statistical Packages for Social Sciences (SPSS) version 23.0 was the software that was used in processing the quantitative data. The findings of the study revealed that 5% of students from well-endowed schools, as against 40.5% of those from less-endowed schools, indicated that they have poor attitudes towards Biology practical lessons and this was confirmed by their teachers. It was also shown that practical lessons in Biology, in both well-endowed and less-endowed Senior High Schools, were greatly impeded by lack of proper laboratory, lack of laboratory assistants/technicians and inadequacy of practical equipment and materials for practical work. Based on the findings of the study, the government, Parent Teacher Associations (PTAs) and other stakeholders should help in providing the needed resources such as well-equipped laboratories and materials among others to facilitate the teaching and learning of Biology practical in the schools.
Thematizing Marriage in Ama Ata Aidoo’s Changes and Chimamanda Ngozi Adichie’s Purple hibiscus: The Dynamics of Modern African Marriage Relationship
Authors: Yankyerah Andrew Kwame
Published: December 2021

The task of this paper is to highlight some of the marriage relationship tendencies that have changed in the modern African Marriage, in relation to the traditional norms, as manifest in two texts of two African Feminist writers. The study thus examines how Ama Ata Aidoo’s Changes and Chimamanda N. Adichie’s Purple Hibiscus explore the marriage institution in Africa and unearth the changing dynamics in it, as it pertains to the modern or post-modern African society. The study concluded that though the dignity of marriage coupled with its necessity as a social institution is unquestionably maintained in our focused African texts, its dynamics, in modern society, must yield to positive change, at least, to reflect the emerging socio-economic trends in African society today.
Recent Rainfall Trend and Abrupt Changes Over Cavally Basin (West Africa)
Authors: Fhorest Yao Blé Anouma , Soro Emile Gneneyougo
Published: December 2021

Aims: Analyze the recent variations in annual and monthly precipitation at 18 pluviometry stations in the Cavally river basin.

Place and Duration of Study: Data of month and annual rainfall data of 37 years (1980-2016) collected from the National direction of Meteorology for Ivory Coast and Guinea and from https://app.climateengine.org/climateEngine for Liberia.

Methodology: Statistical methods are used to highlight the evolution of cumulative annual rainfall and the distribution of the different seasons over the period 1980-2016. Hanning’s low pass, Mann-Kendall classic test, modified Mann-Kendall test, Mann-Kendall seasonal test and Standard Normal Homogeneity Test were applied to identify the existing trend direction and significance of change over time.

Results: The periods 1980-1996 and 1997-2016 could be considered as wet and dry periods respectively (with a rainfall deficit of 18% after the break in 1996). In addition, we observe a decrease in rainy days of strong accumulation that lead to a significant drop in total annual rainfall. Finally, an abnormal increase in rainfall during the dry season months and a decrease in rainfall during the rainy season months. This indicates an intra-seasonal irregularity (shortening of the rainy season and prolongation of the dry season) of precipitation.

Conclusion: The Hanning filter, M-K test and SNHT are non-parametric tests widely used in the study of climate trends. However, the additional consideration of serial autocorrelation (MM-K test) and seasonal trends (M-K-S test) allows to extend and refine the information on climate variability.
Waardenburg Syndrome Type II, Associated with Atrial Septal Defect and Rocker Bottom Foot in a New Born – A Rare Case Presentation
Authors: J. K. Jeffy , Satyendra . , Narayan Jaiprakash
Published: December 2021

Background: There are a number of syndromes with a combination of pigmentary abnormalities, hearing abnormalities and other defects. One among these pigmentary syndromes is waardenburg syndrome, which is further classified into four types. All these types show marked variability even within pedigrees.

Case-Report: We are reporting a case of Waardenburg syndrome type 2, with an unusual presentation of atrial septal defect and rocker bottom foot.

Conclusion: All clinicians on noticing, any child with white forelock of hair or heterochromia iris should get the child’s hearing tested and further systemic evaluation, at the first instance, because an early intervention for hearing impairment and other defects can improve the outcome of child. Family counselling is at-most important for these children with syndromes.

We describe a unique case of Waardenburg syndrome type 2 with an unusual presentation of atrial septal defect and rocker bottom foot.
Pressure-Velocity Coupling Schemes for Bouyancy Driven Flow in a Differentially Heated Cavity Using F.V.M and Matlab
Authors: Mberia Purity , Karanja Stephen , Kimathi Mark
Published: December 2021

Numerical analysis of fluid flow is anchored on the laws of conservation. A challenge in solving the momentum equation arises due to the unavailability of an explicit pressure equation. To avoid solving the pressure term most researchers have eliminated it by cross differentiating the x and the y two dimensional momentum equations and subtracting them. This method introduces more variables to be solved in comparison to the primitive variables and is  restricted to two-dimensional flows as streamlines do not exist in three-dimension. This method thus presents a serious limitation in analysis of fluid flow. In this study an equation for computing pressure has been developed using pressure - velocity coupling and used in solving the governing equations. The performance of three pressure velocity schemes namely; the Semi Implicit Method for Pressure linked Equation (SIMPLE), SIMPLE Revised (SIMPLER) and SIMPLE Consistent (SIMPLEC) for laminar buoyancy driven flow has been tested in order to establish the scheme that gives results consistent with bench mark data. The equations governing the flow are solved iteratively using finite volume method together with the central difference interpolating scheme. The solutions are presented for Rayleigh numbers of 103, 104, and 105. This resulted in the velocity profiles for the SIMPLE, SIMPLER, and SIMPLEC algorithm for a Rayleigh number of 104 and 105 converging to the same path. At a Rayleigh number of 103 however, SIMPLER algorithm undergoes a degradation in convergence with grid refinement at the baffle region. Results predicted by using the SIMPLEC algorithm are thus able to effectively compute the velocity of fluid flow in a differentially heated square enclosure with baffles for both low and higher Rayleigh numbers irrespective of the grid size.
GC-MS Analysis and Antimicrobial Assessment of Syzygium cumini (L.) Skeels Seed Ethanol Extract
Authors: Parimala S. Mabel , Salomi A. Antilin
Published: December 2021

People use plants to treat infections, and this has led to search of antimicrobials from medicinal plants. In this work, we evaluated the ethanol extract of Syzygium cumini seeds for their antibacterial and antifungal activities. Extraction was performed by maceration method using ethanol. The antimicrobial efficacy of the extract was assessed by agar well diffusion method against ten bacterial species, Bacillus cereus, Bacillus subtilis, Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhi, Serratia marcescens, Staphylococcus aureus and Streptococcus mutans, and five fungal species, Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger, Candida albicans and Mucor sp. Minimum inhibitory concentrations (MICs) of the extract were determined by resazurin microtiter plate assay.  Phytochemicals in the extract was identified by gas chromatography mass spectrometry (GC-MS) information.  In agar well diffusion method, Gram-negative bacteria such as P. aeruginosa and S. marcescens, Gram-positive bacteria such as B. subtilis and E. faecalis and fungi A. fumigatus were more susceptible showing larger zones of inhibition.  In resazurin method, low MICs were recorded for bacteria, B. cereus (<7.8 µg) and P. aeruginosa (15.6 µg) and fungi, A. fumigatus (31.2 µg).  Fifteen compounds were identified by GC-MS profiling of the extract.  The antimicrobial activity of the extract can be rightly related to the secondary metabolites in the ethanol extract of Syzygium cumini seeds.
Ergothioneine: a potential antioxidative and antimelanosis agent for food quality preservation
Authors: Kitsanayanyong Lalitphan , Ohshima Toshiaki
Published: December 2021

The global population increase has increased the demand for food products. However, post‐harvest deterioration because of oxidation and discoloration results in a drastic loss of food quality and supply. Thus, research has focused on developing strategies to minimize such losses. One of those strategies includes the application of ergothioneine (ET), a potent hydrophilic antioxidant, to several food products to overcome their short shelf‐life. ET can be synthetic or derived from several species of edible mushrooms and their extracts, which are known sources of natural ET. Given the reported potential of ET in food quality preservation, this review compiles the recent applications of ET as a preservative for maintaining the quality of food commodities.
Electronegativity‐Induced Charge Balancing to Boost Stability and Activity of Amorphous Electrocatalysts
Authors: Zhou Yao , Hao Wei , Zhao Xiaoxu , Zhou Jiadong , Yu Huimei , Lin Bo , Liu Zheng , Pennycook Stephen J. , Li Shuzhou , Fan Hong Jin
Published: December 2021

Amorphization is an efficient strategy to activate intrinsically inert catalysts. However, the low crystallinity of amorphous catalysts often causes high solubility and poor electrochemical stability in aqueous solution. Here, a different mechanism is developed to simultaneously stabilize and activate the water‐soluble amorphous MoSxOy via a charge‐balancing strategy, which is induced by different electronegativity between the co‐dopants Rh (2.28) and Sn (1.96). The electron‐rich Sn prefers to stabilize the unstable apical O sites in MoSxOy through charge transfer, which can prevent the H from attacking. Meanwhile, the Rh, as the charge regulator, shifts the main active sites on the basal plane from inert Sn to active apical Rh sites. As a result, the amorphous RhSn‐MoSxOy exhibits drastic enhancement in electrochemical stability (η10 increases only by 12 mV) after 1000 cycles and a distinct activity (η10: 26 mV and Tafel: 30.8 mV dec−1) for the hydrogen evolution reaction in acidic solution. This work paves a route for turning impracticably water‐soluble catalysts into treasure and inspires new ideas to design high‐performance amorphous electrocatalysts.
Emerging 4D Printing Strategies for Next‐Generation Tissue Regeneration and Medical Devices
Authors: Wang Yue , Cui Haitao , Esworthy Timothy , Mei Deqing , Wang Yancheng , Zhang Lijie Grace
Published: December 2021

The rapid development of 3D printing has led to considerable progress in the field of biomedical engineering. Notably, 4D printing provides a potential strategy to achieve a time‐dependent physical change within tissue scaffolds or replicate the dynamic biological behaviors of native tissues for smart tissue regeneration and the fabrication of medical devices. The fabricated stimulus‐responsive structures can offer dynamic, reprogrammable deformation or actuation to mimic complex physical, biochemical, and mechanical processes of native tissues. Although there is notable progress made in the development of the 4D printing approach for various biomedical applications, its more broad‐scale adoption for clinical use and tissue engineering purposes is complicated by a notable limitation of printable smart materials and the simplistic nature of achievable responses possible with current sources of stimulation. In this review, the recent progress made in the field of 4D printing by discussing the various printing mechanisms that are achieved with great emphasis on smart ink mechanisms of 4D actuation, construct structural design, and printing technologies, is highlighted. Recent 4D printing studies which focus on the applications of tissue/organ regeneration and medical devices are then summarized. Finally, the current challenges and future perspectives of 4D printing are also discussed.
Room Temperature Phosphorescent (RTP) Thermoplastic Elastomers with Dual and Variable RTP Emission, Photo‐Patterning Memory Effect, and Dynamic Deformation RTP Response
Authors: Zhang Yuefa , Sun Qikun , Yue Lingtai , Wang Yaguang , Cui Shuaiwei , Zhang Haichang , Xue Shanfeng , Yang Wenjun
Published: December 2021

Room temperature phosphorescent (RTP) polymers have advantages of strength, toughness, and processing and application flexibility over organic small molecular crystals, but the current RTP polymers are all from rigid plastics and involve chemical linkage and hydrogen and ionic bonds, and thermoplastic RTP elastomer has not been attempted and realized. Moreover, solution‐processed films by simply mixing polymers and organic RTP materials can only show weak and single blue RTP. Here it is presented that such elastomer films, once thermomechanically plasticized, can emit bright and long‐lived dual RTP. Moreover, they exhibit photo‐activation memory effect, variable RTP colors and dynamic deformation RTP response. These results reveal that thermoplasticizing has altered the dispersion states and micro‐environment of RTP molecules in matrix, and the cohesion of elastic polymer itself can also greatly restrict non‐radiative relaxations to boost both blue mono‐molecular and yellow micro‐crystalline RTP. This work provides an effective and versatile processing strategy for tuning and enhancing the RTP properties of doped RTP polymers.
Microengineered Multi‐Organoid System from hiPSCs to Recapitulate Human Liver‐Islet Axis in Normal and Type 2 Diabetes
Authors: Tao Tingting , Deng Pengwei , Wang Yaqing , Zhang Xu , Guo Yaqiong , Chen Wenwen , Qin Jianhua
Published: December 2021

Type 2 diabetes mellitus (T2DM) is a systematic multi‐organ metabolic disease, which is characterized by the dynamic interplay among different organs. The increasing incidence of T2DM reflects an urgent need for the development of in vitro human‐relevant models for disease study and drug therapy. Here, a new microfluidic multi‐organoid system is developed that recapitulates the human liver‐pancreatic islet axis in normal and disease states. The system contains two compartmentalized regions connected by a microchannel network, enabling 3D co‐culture of human induced pluripotent stem cells (hiPSC)‐derived liver and islet organoids for up to 30 days under circulatory perfusion conditions. The co‐cultured liver and islet organoids exhibit favorable growth and improved tissue‐specific functions. Transcriptional analyses reveal the activation of metabolically relevant signaling pathways in the co‐cultured organoids. Notably, the co‐culture system facilitates sensitive glucose‐stimulated insulin secretion from islet organoids and increased glucose utilization in liver organoids by glucose tolerance tests. Both liver and islet organoids display mitochondrial dysfunction and decreased glucose transport capacity under high glucose conditions, which can be alleviated by metformin treatment. This novel multi‐organoid system can recapitulate human‐relevant liver‐islet axis under both physiological and pathological conditions, providing a unique platform for future T2DM research and drug development.
Light‐Induced Synaptic Effects Controlled by Incorporation of Charge‐Trapping Layer into Hybrid Perovskite Memristor
Authors: Zawal Piotr , Mazur Tomasz , Lis Maria , Chiolerio Alessandro , Szaciłowski Konrad
Published: December 2021

Organic‐inorganic perovskites despite being known for their extraordinary performance in solar cell research areas are also a workhorse in the field of unconventional information processing. Here, a neuromimetic behaviour is presented in a perovskite device with the potential to act as an artificial synapse. In addition, perovskite layer is combined with one of the non‐stoichiometric polymeric forms of carbon nitride (C3N4). Such a device can operate not only according to the principles of non‐von Neumann architecture but also utilizes two different stimuli as information carriers–electric current and/or light. This in turn can lead towards the development of next‐generation information processing/storage units.
2D Mg‐Cu Intermetallic Compounds with Nontrivial Band Topology and Dirac Nodal Lines
Authors: Wu Rongting , Wu Ze‐Bin , Božović Ivan
Published: December 2021

Synthesis of vertical heterostructures that include atomically thin layers of materials with topologically nontrivial energy bands is desirable for exploring exotic quantum states. Here, the authors report on atomic‐layer‐by‐layer deposition of magnesium on copper(111) surface by molecular beam epitaxy, monitored in situ by low‐energy electron microscopy and diffraction, and modeled by ab initio theory. It is found that a 2D MgCu2 intermetallic compound forms during initial Mg deposition and persists till a full monolayer of Mg is formed. Deposition of additional Mg triggers a phase transition from the commensurate MgCu2 to an incommensurate Mg2Cu layer and enables growth of the second layer of Mg. Ab initio calculations indicate non‐trivial topology of the electron bands in the interfacial Mg2Cu layer and the existence of Dirac nodal lines near the Fermi level. The new 2D Mg2Cu material emerges as a promising platform to study new topological states of matter.
Determining Structure‐Activity Relationships in Oxide Derived CuSn Catalysts During CO2 Electroreduction Using X‐Ray Spectroscopy
Authors: Pardo Pérez Laura C. , Arndt Alexander , Stojkovikj Sasho , Ahmet Ibbi Y. , Arens Joshua T. , Dattila Federico , Wendt Robert , Guilherme Buzanich Ana , Radtke Martin , Davies Veronica , Höflich Katja , Köhnen Eike , Tockhorn Philipp , Golnak Ronny , Xiao Jie , Schuck Götz , Wollgarten Markus , López Núria , Mayer Matthew T.
Published: December 2021

The development of earth‐abundant catalysts for selective electrochemical CO2 conversion is a central challenge. CuSn bimetallic catalysts can yield selective CO2 reduction toward either CO or formate. This study presents oxide‐derived CuSn catalysts tunable for either product and seeks to understand the synergetic effects between Cu and Sn causing these selectivity trends. The materials undergo significant transformations under CO2 reduction conditions, and their dynamic bulk and surface structures are revealed by correlating observations from multiple methods—X‐ray absorption spectroscopy for in situ study, and quasi in situ X‐ray photoelectron spectroscopy for surface sensitivity. For both types of catalysts, Cu transforms to metallic Cu0 under reaction conditions. However, the Sn speciation and content differ significantly between the catalyst types: the CO‐selective catalysts exhibit a surface Sn content of 13 at. % predominantly present as oxidized Sn, while the formate‐selective catalysts display an Sn content of ≈70 at. % consisting of both metallic Sn0 and Sn oxide species. Density functional theory simulations suggest that Snδ+ sites weaken CO adsorption, thereby enhancing CO selectivity, while Sn0 sites hinder H adsorption and promote formate production. This study reveals the complex dependence of catalyst structure, composition, and speciation with electrochemical bias in bimetallic Cu catalysts.
Cross‐cultural variation in thirst perception in hot‐humid and hot‐arid environments: Evidence from two small‐scale populations
Authors: Rosinger Asher Y. , Bethancourt Hilary J. , Swanson Zane S. , Lopez Kaylee , Kenney W. Larry , Huanca Tomas , Conde Esther , Nzunza Rosemary , Ndiema Emmanuel , Braun David R. , Pontzer Herman
Published: December 2021

Objectives

Thirst is an evolved central homeostatic feedback system that helps regulate body water for survival. Little research has examined how early development and exposure to extreme environments and water availability affect thirst perception, particularly outside Western settings. Therefore, we compared two indicators of perceived thirst (current thirst and pleasantness of drinking water) using visual scales among Tsimane' forager‐horticulturalists in the hot‐humid Bolivian Amazon and Daasanach agro‐pastoralists in hot‐arid Northern Kenya.

Methods

We examined how these measures of perceived thirst were associated with hydration status (urine specific gravity), ambient temperatures, birth season, age, and population‐specific characteristics for 607 adults (n = 378 Tsimane', n = 229 Daasanach) aged 18+ using multi‐level mixed‐effect regressions.

Results

Tsimane' had higher perceived thirst than Daasanach. Across populations, hydration status was unrelated to both measures of thirst. There was a significant interaction between birth season and temperature on pleasantness of drinking water, driven by Kenya data. Daasanach born in the wet season (in utero during less water availability) had blunted pleasantness of drinking water at higher temperatures compared to those born in the dry season (in utero during greater water availability).

Conclusions

Our findings suggest hydration status is not a reliable predictor of thirst perceptions in extreme‐hot environments with ad libitum drinking. Rather, our findings, which require additional confirmation, point to the importance of water availability during gestation in affecting thirst sensitivity to heat and water feedback mechanisms, particularly in arid environments. Thirst regulation will be increasingly important to understand given climate change driven exposures to extreme heat and water insecurity.