bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of a Small and Fast Planing Boat’s Seakeeping Performance at the Design Stage
Authors: Kim Dong Jin , Kim Sun Young
Published: April 2021

Seakeeping performance of a planing boat should be sufficiently considered and evaluated at the design stage for its safe running in rough seas. Model tests in seakeeping model basins are often performed to predict the performance of full-scale planing boats. But, there are many limitations of tank size and wave maker capacity, in particular, for fast small planing boats due to small scale ratio and high Froude numbers of their scale models. In this research, scale model tests are tried in various test conditions, and results are summarized and analyzed to predict a 3 ton-class fast small planing boats designed. In a long and narrow tank, towing tests for a bare hull model are performed with regular head waves and long crested irregular head waves. Motion RAOs are derived from irregular wave tests, and they are in good agreements with RAOs in regular waves. Next, model ships with one water-jet propulsion system are built, and free running model tests are performed in ocean basins. Wave conditions such as significant heights, modal periods, and directions are varied for the free running tests. Motion RMS values, and RAOs are obtained through statistical approaches. They are compared with the results in captive tests for the bare hull model, and are used to predict the full-scale boat performances.
Spiritual Development as a Factor of Professional and Personal Qualities of Modern Students
Authors: Kuatova Zh.Zh. , Buletova L.A. , Makhmutova K. I. , Suleimenova S.N. , Nuridinova G. A. , Suleimenova A. A.
Published: April 2021

This article deals with the formation of spiritual development of students, caused by three main circumstances: First, the need to study the changes taking place in society and changes in the mechanism of formation of spiritual culture of students. The hierarchy of values and spiritual activity of new generations of students differ significantly from previous generations' value-normative system. Secondly, students' innovative role in youth culture and a special place of higher education as a factor in the formation of students' spiritual culture. Third, considering students' specific qualities and characteristics as a special social group, the study of youth spiritual culture can determine the parameters of society's spiritual development prospects. In the works of the researchers mentioned above, in particular, the social aspects of cultural self-identification of young people were touched upon. The influence of deformations of the value-normative system on the strengthening of the processes of individualization of consciousness of young people taking place against the background of the destruction of rigid traditional forms of social control and the absence of new moral boundaries was studied. In connection with the social and educational environment, the issues of adaptation of young people were considered. Applied research in the higher education system reflects the urgent problems of universities. It contributes to the clarification of hypotheses and building theories of the middle level, including issues of institutional impact institutions of higher education on the formation of students' spiritual development, especially in terms of its professional component. The analysis of requests, expectations, and preferences of young generations in the field of culture makes it possible to form a holistic view of the development of leisure behavioral stereotypes
COVID-19, Norms, and Discrimination against Female Gender in Nigeria: Focus on Implications for Mental Health Counselling
Authors: Joseph Chinedu Hilary , Alika Henrietta Ijeoma , Genevieve Anikelechi Ijeoma , Thobejane T.D.
Published: April 2021

The COVID-19 outbreak is inflicting different societies of the world with an untold and unprecedented hardship. However, the extent of impacts is bound to differ across groups, gender, economies, and countries. Given how the pandemic affects particular groups, this paper focuses on girls/young women and how Covid-19 may further strengthen gender norms and discriminations as risk factors of their mental health. In some societies, right from birth, the life experiences of the female child differ from the male child. At every stage of development, girls are more likely than boys to confront a host of challenges associated with discrimination and norms, which are gender-based. With the effects of the current pandemic evident in reduced access to health care, education, teenage pregnancy, and being vulnerable, young women and girls are more at the receiving end of their impacts. These stand as hindrances to the girl child's mental health because they tend to constitute anxiety, depression, self-harm, or even suicide and weakens her will power to make proper adjustment to life issues. This paper concludes that given that the impacts of COVID-19 are not gender-blind (affecting both genders), therefore the designing policy responses to the current pandemic should not be either. As we all continue to face this overwhelming Covid-19 pandemic, the study recommends that the vulnerable (especially girls and young women) should not be neglected or ignored. This is possible by not forgetting the inequalities that may worsen the conditions of girls because of the crisis
Lifelong Learning in the Age of Data: Opportunities and Policy Impact
Authors: Dichaba Mpho M.
Published: April 2021

This article entitled "Lifelong Learning in the Age of Data: Opportunities and Policy Impact", Author, Mpho M. Dichaba, published in Volume 9, Issue 1, pp 64-70 retracted by the publisher due to containing THE data without authorisation for use.
Thermal Degradation of β-Carotene from Macauba Palm: Mathematical Modeling and Parameter Estimation
Authors: Valério Pedro Prates , Brandão Amanda Lemette , Frias Celayeta Jesus Maria , Cren Erika Cristina
Published: April 2021

Worldwide, there is a current need for new sources of vegetable oils. The natural content of total carotenoids in Acrocomia aculeata palm oil (up to 378 µg.g-1) surpasses that of many other tropical fruits, making it one of its main compositional characteristics. As far as can be verified, there is no available information on the degradation kinetics of carotenoids for A. aculeata oil, which is required to describe reaction rates and to predict changes that can occur during food processing. The present study considered prediction abilities that have emerged with the use of specific kinetic data and procedures to understand thermal processing better, as an essential unity operation. Two kinetic mechanisms were proposed to describe the overall thermal degradation of carotenoids in the oil; the first one consists of three reaction steps while the other presents only one-step reaction. Mass balance equations were numerically solved by a Backward Differentiation Formula technique. The kinetic parameters from both models were estimated through a hybrid optimisation method using the Particle Swarm Optimization and the Gauss-Newton method, followed by statistical analyses. The model with more than one reaction was shown to be overparameterized and was discarded. The model with a single reaction was highly suited to handle the experimental data available, and the dependency of its rate constant on temperature was expressed according to Arrhenius law. As far we know, this is the first time the kinetics of carotenoids thermal degradation in A. aculeata oil is investigated through modelling simulation.
Consumers’ Perception and Consumption of Sunflower Oil in Kumasi, Ghana
Authors: Nimoh Fred , Anaman Richmond , Abubakar Alhassan , Bishop Bortey Manison , Darko Daniel Opoku
Published: April 2021

Consumption pattern among indigenous groups is usually influenced by consumers' sociocultural and perceptual factors. This study employs the binary logit model to analyse the factors that influence the consumption of sunflower oil in Kumasi, Ghana. A cross-sectional approach was used to obtain data from 200 consumers who were selected using a multi-stage sampling method. The results showed that a majority (93%) of the respondents were aware of the availability of sunflower oil on the local market and a third (69.5%) had used it for cooking before. The respondents agreed with the perception statements that sunflower oil is healthy, expensive, reduces the risk of heart diseases and cancer and has better frying performance. The empirical results of the logit regression model showed that consumption of sunflower oil is influenced by household size, awareness of the product and perceptions on health benefits, price and frying performance of sun ower oil. The price of the oil was identified as the most important constraint to its use albeit it had no negative effect on its consumption. Investments in the production and promotional strategies on the use of sunflower oil should consider the significant variables that have influence on its consumption.
Industrial Practice for Reducing Defective Sterile Milk Products Produced Using Overpressure Rotary Retorts
Authors: Pamuji Muhamad Wahyu , Purnomo Eko Hari , Sitanggang Azis Boing
Published: April 2021

Indonesian consumers are fond of commercially sterilized milk as indicated by increasing product sales. High demand for products intensifies the need to increase productivity, generally achieved by minimizing product defects. This study aimed to reduce the number of defects in commercially sterilized milk produced using overpressure rotary retorts. Based on Pareto analysis, the percentage of defective products was 5.14% of which 2.37% were dented bottles. A cause-effect diagram (Ishikawa Diagram) was used to find the root cause of dented bottles. The pressure difference between the retort chamber (external pressure) and inside the product packaging (internal pressure), and the number of bottles stacked inside the retort basket (bottle density) were found as major factors for causing dented bottles. The internal pressure was 1.20 bar higher than the external pressure. By reducing the pressure difference to 0.40 bar, the percentage of dented bottles could be reduced to 0.79%. Applying the low-est bottle density (73% of the retort basket area occupied by bottles) during the sterilization process could decrease the number of dented bottles, however, it also increased the appearance of striped lids. The best conditions for sterilization (pressure difference = 0.40 bar; number of bottles/basket = 1938 bottles) which were used in the three-month full-scale production trial reduced the percentage of defective products from 5.14% to 2.24% of which 0.76% were dented bottles. Setting the retort pressure at 2.80 bar could avoid 52,920 defective bottles of commercially sterilized products per month.
Improving oligo-conjugated antibody signal in multimodal single-cell analysis
Authors: Buus Terkild B , Herrera Alberto , Ivanova Ellie , Mimitou Eleni , Cheng Anthony , Herati Ramin S , Papagiannakopoulos Thales , Smibert Peter , Odum Niels , Koralov Sergei B
Published: April 2021

Simultaneous measurement of surface proteins and gene expression within single cells using oligo-conjugated antibodies offers high-resolution snapshots of complex cell populations. Signal from oligo-conjugated antibodies is quantified by high-throughput sequencing and is highly scalable and sensitive. We investigated the response of oligo-conjugated antibodies towards four variables: concentration, staining volume, cell number at staining, and tissue. We find that staining with recommended antibody concentrations causes unnecessarily high background and amount of antibody used can be drastically reduced without loss of biological information. Reducing staining volume only affects antibodies targeting abundant epitopes used at low concentrations and is counteracted by reducing cell numbers. Adjusting concentrations increases signal, lowers background, and reduces costs. Background signal can account for a major fraction of total sequencing and is primarily derived from antibodies used at high concentrations. This study provides new insight into titration response and background of oligo-conjugated antibodies and offers concrete guidelines to improve such panels.
Heterogeneity in transmissibility and shedding SARS-CoV-2 via droplets and aerosols
Authors: Chen Paul Z , Bobrovitz Niklas , Premji Zahra , Koopmans Marion , Fisman David N , Gu Frank X
Published: April 2021

Background:

Which virological factors mediate overdispersion in the transmissibility of emerging viruses remains a long-standing question in infectious disease epidemiology.

Methods:

Here, we use systematic review to develop a comprehensive dataset of respiratory viral loads (rVLs) of SARS-CoV-2, SARS-CoV-1 and influenza A(H1N1)pdm09. We then comparatively meta-analyze the data and model individual infectiousness by shedding viable virus via respiratory droplets and aerosols.

Results:

The analyses indicate heterogeneity in rVL as an intrinsic virological factor facilitating greater overdispersion for SARS-CoV-2 in the COVID-19 pandemic than A(H1N1)pdm09 in the 2009 influenza pandemic. For COVID-19, case heterogeneity remains broad throughout the infectious period, including for pediatric and asymptomatic infections. Hence, many COVID-19 cases inherently present minimal transmission risk, whereas highly infectious individuals shed tens to thousands of SARS-CoV-2 virions/min via droplets and aerosols while breathing, talking and singing. Coughing increases the contagiousness, especially in close contact, of symptomatic cases relative to asymptomatic ones. Infectiousness tends to be elevated between 1 and 5 days post-symptom onset.

Conclusions:

Intrinsic case variation in rVL facilitates overdispersion in the transmissibility of emerging respiratory viruses. Our findings present considerations for disease control in the COVID-19 pandemic as well as future outbreaks of novel viruses.

Funding:

Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery Grant program, NSERC Senior Industrial Research Chair program and the Toronto COVID-19 Action Fund.
Synaptic learning rules for sequence learning
Authors: Reifenstein Eric Torsten , Bin Khalid Ikhwan , Kempter Richard
Published: April 2021

Remembering the temporal order of a sequence of events is a task easily performed by humans in everyday life, but the underlying neuronal mechanisms are unclear. This problem is particularly intriguing as human behavior often proceeds on a time scale of seconds, which is in stark contrast to the much faster millisecond time-scale of neuronal processing in our brains. One long-held hypothesis in sequence learning suggests that a particular temporal fine-structure of neuronal activity — termed ‘phase precession’ — enables the compression of slow behavioral sequences down to the fast time scale of the induction of synaptic plasticity. Using mathematical analysis and computer simulations, we find that — for short enough synaptic learning windows — phase precession can improve temporal-order learning tremendously and that the asymmetric part of the synaptic learning window is essential for temporal-order learning. To test these predictions, we suggest experiments that selectively alter phase precession or the learning window and evaluate memory of temporal order.
To trust or not to trust an explanation: using LEAF to evaluate local linear XAI methods
Authors: Amparore Elvio , Perotti Alan , Bajardi Paolo
Published: April 2021

The main objective of eXplainable Artificial Intelligence (XAI) is to provide effective explanations for black-box classifiers. The existing literature lists many desirable properties for explanations to be useful, but there is a scarce consensus on how to quantitatively evaluate explanations in practice. Moreover, explanations are typically used only to inspect black-box models, and the proactive use of explanations as a decision support is generally overlooked. Among the many approaches to XAI, a widely adopted paradigm is Local Linear Explanations—with LIME and SHAP emerging as state-of-the-art methods. We show that these methods are plagued by many defects including unstable explanations, divergence of actual implementations from the promised theoretical properties, and explanations for the wrong label. This highlights the need to have standard and unbiased evaluation procedures for Local Linear Explanations in the XAI field. In this paper we address the problem of identifying a clear and unambiguous set of metrics for the evaluation of Local Linear Explanations. This set includes both existing and novel metrics defined specifically for this class of explanations. All metrics have been included in an open Python framework, named LEAF. The purpose of LEAF is to provide a reference for end users to evaluate explanations in a standardised and unbiased way, and to guide researchers towards developing improved explainable techniques.
A dual model node based optimization algorithm for simultaneous escape routing in PCBs
Authors: Ali Asad , Naveed Anjum , Zeeshan Muhammad
Published: April 2021

Simultaneous Escape Routing (SER) is the escaping of circuit pins simultaneously from inside two or more pin arrays. This is comparatively difficult as compared to routing in a single array and has not been addressed by previous studies. The increase in pin array complexity has made the manual SER in PCBs a very inefficient and tedious task and there surely is need for the automated routing algorithms. In this work, we propose network flow based optimal algorithm that uses integer linear program to solve SER problem and area routing problem in two stages. In the first stage, pins are escaped to the boundaries of pin arrays simultaneously. These escaped pins are connected with each other in the second stage. The proposed algorithm is tested for different benchmark sizes of grids and the results show that it is not only better in terms of routability but also outperforms existing state of the art algorithms in terms of time consumption. The existing algorithms either fails to achieve higher routability or have larger time complexities, whereas the proposed algorithm achieves 99.9% routability and is also independent of grid topology and component pin arrangement, which shows the superiority of proposed algorithm over the existing algorithms.
The physiological response of Ectomycorrhizal fungusLepista sordidato Cd and Cu stress
Authors: Dachuan Yin , Jinyu Qi
Published: April 2021

Ectomycorrhizal fungi (ECMF) can develop the resistance of host plants to heavy metal stress. However, little is known about the response of ECMF to heavy metal exposure. In this study, the growth and physiological indices ofLepista sordidaunder Cd and Cu stress were studied. The growth ofL. sordidaon PDA medium under Cd and Cu stress was observed using scanning electron microscopy (SEM). After the addition of Cd and Cu to the medium, the mycelium started twisting, breaking, sticking together, and even dissolving. In the control group, a good and luxuriant mycelium growth ofL. sordidaalong with the numerous clamp connections was observed. The mycelial biomass decreased with increasing concentrations of heavy metals in a liquid medium. The catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), and ascorbate peroxidase (APX) activities were also investigated, and the results showed that the Cd and Cu treatments caused a significant increase in the antioxidant enzyme activities. The contents of soluble protein, soluble sugar, and free proline inL. sordidawere investigated, and it was found that the contents initially increased and then decreased with the increasing concentrations of Cd and Cu. However, the content of malondialdehyde (MDA) increased with the increasing concentrations of Cd and Cu. In conclusion, the present study provides a theoretical basis for the better utilization of Ectomycorrhizal fungal resources for the remediation of soil contaminated with heavy metal.
Recombinant fusion protein by lysozyme and antibacterial peptide enhances ischemic wound healing via angiogenesis and reduction of inflammation in diabetic db/db mice
Authors: Li Wei , Jiang Yu-Xin , Chen Qing-Ying , Wang Guo-Guang
Published: April 2021

Background & aims

Lysozyme and antibacterial peptides have been reported to broad-spectrum antibacterial activity and can further improve wound healing. The aim of this study was to assess the effectiveness of a recombinant fusion protein created by combining lysozyme and an antibacterial peptide in forming new vessels and wound healing in an ischemic hind limb.

Methods

An ischemic hind limb model was established by isolation and ligation of the femoral artery in diabetic db/db mice. Cutaneous wounds were created with or without ischemia. Adductor muscles and wounds were treated with or without the fusion protein.

Results

The fusion protein accelerated ischemic diabetic wound healing and attenuated impairment of ischemic adductor muscle . Further, the fusion protein elevated expression of platelet derived growth factor (PDGF) and vascular endothelial growth factor (VEGF) protein and mRNA in ischemic adductor muscle, reduced levels of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) in serum and expression of phosphorylated nuclear factor κB (p-NF-κB) and p-IKB α in ischemic adductor. The fusion protein also enhanced levels of phosphorylated VEGF and PDGF receptors in the ischemic adductor muscles from diabetic db/db mice.

Conclusion

The data showed that the beneficial effects of the fusion protein on ischemic wound healing may be associated with angiogenesis and reduction of inflammatory response in the ischemic adductor muscles of diabetic db/db mice.
A quantitative assessment of site-level factors in influencing Chukar (Alectoris chukar) introduction outcomes
Authors: Smith Austin M. , Cropper, Jr. Wendell P. , Moulton Michael P.
Published: April 2021

Chukar partridges (Alectoris chukar) are popular game birds that have been introduced throughout the world. Propagules of varying magnitudes have been used to try and establish populations into novel locations, though the relationship between propagule size and species establishment remains speculative. Previous qualitative studies argue that site-level factors are of importance when determining where to release Chukar. We utilized machine learning ensembles to evaluate bioclimatic and topographic data from native and naturalized regions to produce predictive species distribution models (SDMs) and evaluate the relationship between establishment and site-level factors for the conterminous United States. Predictions were then compared to a distribution map based on recorded occurrences to determine model prediction performance. SDM predictions scored an average of 88% accuracy and suitability favored states where Chukars were successfully introduced and are present. Our study shows that the use of quantitative models in evaluating environmental variables and that site-level factors are strong indicators of habitat suitability and species establishment.
Plastic additives: challenges in ecotox hazard assessment
Authors: Barrick Andrew , Champeau Olivier , Chatel Amélie , Manier Nicolas , Northcott Grant , Tremblay Louis A.
Published: April 2021

The risk of plastic debris, and specifically micro(nano)plastic particles, to ecosystems remains to be fully characterized. One particular issue that warrants further characterization is the hazards associated with chemical additives within micro(nano)plastic as they are not chemically bound within the polymers and can be persistent and biologically active. Most plastics contain additives and are therefore potential vectors for the introduction of these chemicals into the environment as they leach from plastic, a process that can be accelerated through degradation and weathering processes. There are knowledge gaps on the ecotoxicological effects of plastic additives and how they are released from parent plastic materials as they progressively fragment from the meso to micro and nano scale. This review summarizes the current state of knowledge of the ecotoxicity of plastic additives and identifies research needs to characterize the hazard they present to exposed biota. The potential ecological risk of chemical additives is of international concern so key differences in governance between the European Union and New Zealand to appropriately characterize their risk are highlighted.
Exploring the comparison between bilingual and monolingual students perception of classroom environment
Authors:   Ferdowsi University of Mashhad Iran, Reza Pahlavannezhad Mohammad , Heidarypur Mohammad ,   Ferdowsi University of Mashhad Iran
Published: April 2021

Bilingualism is a phenomenon, visible in most of the countries all over the world. According to statistics, released in 2017, they make up 42% of the whole country’s population in Iran. The statistical population of this research includes 70 bilinguals and monolinguals, from among BA students of Ferdowsi University of Mashhad. Through random cluster sampling, these individuals were selected, among whom 38 students were monolingual (Farsi), 18 students bilingual (Farsi-Kurdish), and 14 students bilingual (Farsi-Turkish). Perceptions of classroom environment questionnaire (WIHIC) has been used as a research tool. The result shows that all the subscales are significant. In fact, the comprehensiveness variable is significant at P<0/01 and support variables are significant at P<0/001. To determine the groups’ priorities, Post Hoc Test has been used and the results represented the fact that there is significant difference be-tween the perception of classroom environment in the bilingual groups (Turkish and Kurdish) and monolingual group (P<0.001), yet there was no significant difference between the two bi-lingual groups (P>0.05). Thus, the perception of classroom environment and its subscales in the bilinguals’ group has been significantly higher than the monolingual group; however, there is no significant difference between the bilingual groups (Farsi-Kurdish and Farsi- Turkish).
Indications of lexical-semantic changes in the Arabisms of the Kingdom of Granada (1493-1612): the lexical competition between almádena and martillo
Authors:   Universidad de Granada (España), González Sopeña Inmaculada
Published: April 2021

The objective of the present study is to analyze a couple of lexical items formed by an Arabism and a Romance voice (almádena and martillo) through a corpus of documents linked to the ancient Kingdom of Granada (i.e. the current provinces of Málaga, Almería and Granada) in the late 15th century to 17th century. That documentation includes different types of texts as the correspondence of Hernando de Zafra or texts linked to the building construction at that time. Due to the historical, political, social and religious peculiarities of the Kingdom of Granada there is a persistence of lexicon of Arab origin over the above two centuries with regard to other Spanish-speaking territories. However, Arabic loanwords in Spanish lexicon are subjected to specialization processes or semantic restrictions, as exemplified in the case of almádena. This voice lexically competed with the Romance voice martillo, but, finally, the first one suffered a process of semantic restriction and it is actually cornered in some dialectal areas
¿Existen diferencias entre los formantes de [ə] y [ɯ] en el mapudungun hablado por niños bilingües del Alto Bío-Bío?
Authors: Henríquez B. Marisol , Fuentes G. Darío ,   Universidad de Concepción (Chile)
Published: April 2021

Los primeros estudios sobre la sexta vocal del mapudungun, de corte articulatorio, la han asociado con dos alófonos: uno central [ə] y otro posterior [ɯ]. Sin embargo, las aproximaciones acústicas no reportan un alófono posterior [ɯ], sino, más bien, uno central. Este trabajo presenta una descripción acústica de la sexta vocal del mapudungun producida por niños bilingües del Alto Bío-Bío. Se realizó un análisis de los dos primeros formantes normalizados de las realizaciones de /ə/ y se hicieron comparaciones de estos resultados por sector y comunidad. Los resultados evidencian la presencia de dos alófonos: uno central-posterior, en contextos en los que debiera aparecer [ə], y otro central, en contextos en los que debiera aparecer [ɯ]. Estos hallazgos son coherentes con otros estudios realizados desde una perspectiva acústica, pero difieren de las primeras aproximaciones articulatorias.
Dinâmica econômica mesorregional do setor agropecuário do estado do Ceará no período 2000-2015
Authors: Alcântara Moura José Ediglê , De Lima Júnior Francisco Do O' , Alves Denis Fernandes
Published: April 2021

A reestruturação produtiva alicerçada na inserção competitiva encontra na agropecuária do estado do Ceará sua reprodução como um dos signos da modernização econômica deste estado. Tal foi o suporte de condução da agricultura cearense nos últimos anos. Neste trabalho investiga-se a dinâmica econômica da agropecuária cearense durante o período de 2000 a 2015, considerando as suas distintas mesorregiões. Utilizou-se bancos de dados de órgãos oficiais públicos, como o IBGE. Os resultados mostram que as culturas frutícolas, como melão e melancia, obtiveram maior expansão, enquanto feijão e milho foram as culturas que mais arrefeceram em termos de área plantada e quantidade produzida. Na análise por mesorregião, as Mesorregiões Jaguaribe e Noroeste revelam-se como as de maior produção frutícola do estado, enquanto nos Sertões predomina a ovinocaprinocultura.
Green Synthesis, Characterization and In-vitro Antioxidant Property of Silver Nanoparticles Using the Aqueous Leaf Extract of Justicia carnea
Authors: Salaudeen I. O. , Olajuwon M. O. , Ajala A. B. , Abdulkareem T. O. , Adeniyi S. A. , Jisu S. A. , Omisore M. O. , Abdulahi M. D. , Abdulazeez J. D. , Igbalaye J. O. , Adeyemo G. A.
Published: April 2021

This study investigated the synthesis, characterization and in vitro antioxidant activity of silver nanoparticles (AgNPs) using the aqueous leaf extract of Justicia carnea.  The aqueous leaf extract of J. carnea was used as a potential reducing and capping agent. To identify the compounds responsible for the reduction of silver ions, the functional groups present in the plant extract were subjected to FTIR. The in vitro antioxidant activity of synthesized nanoparticles was evaluated in terms of ferric reducing antioxidant potential (FRAP), DPPH (1,1-diphenyl-2-picrylhydrazyl) and ABTS (2,2`-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) free radicals scavenging assays. The surface plasmon resonance confirmed the formation of AgNPs with maximum absorbance at kmax = 446 nm. FTIR revealed the biological macromolecules of J. carnea leaf extract involved in the synthesis and stabilization of AgNPs. UV-Visible spectrophotometer showed absorbance peak in the range of 436-446 nm. The silver nanoparticles exhibited moderate antioxidant activities compared to standard antioxidants (ascorbic acid and BHT). These results confirmed this protocol as simple, eco-friendly, nontoxic and an alternative for conventional physical and chemical methods. It can be concluded that J. carnea leaf extract can be used effectively in the production of potential antioxidant AgNPs which could be useful in various bio-applications such as cosmetics, food and biomedical industry.
Social Behavior of Sotalia Fluviatilis (Gervais & Deville, 1853) (Cetacea, Delphinidae), in the Northern Channel of the Amazon River, Amapá, Brazil
Authors: Miranda Artur Lagoia Fonseca de , Araújo Andréa Soares de , Campos Carlos Eduardo Costa
Published: April 2021

Sotalia fluviatilis is known as “tucuxi” is endemic to the rivers of the Amazon basin, with aggregations of individuals at the mouths of rivers and canals, it is an almost endangered species and information about it is lacking in the state of Amapá. This study was aimed at monitoring the social behavior of S. fluviatilis in the northern channel of the Amazon River, Amapá, Brazil. Monitoring was carried out from a fixed point on the bank of the northern channel of the Amazon River, located in a Private Reserve of Natural Heritage. Ninety-six days of monitoring were carried out from a fixed point of observation, totaling 480 hours of sample effort. S. fluviatilis was frequently observed throughout the year in predominantly small groups formed mostly by two to three adult animals. Young individuals were observed in larger groups of four to six individuals, formed during activities such as feeding or for protection. Behavioral activities included slow and fast travel, which were in most cases associated with other behaviors, mainly foraging and socializing. The largest number of sightings of socialization occurred in the months of January and February, when river water levels are high. Studies on key species are essential for decision making, in order to optimize conservation strategies for this aquatic mammal in the Amapá. As a suggestion for conservation measures, it would be the distancing of vessels when they perceive a group of porpoises using the region, thus stimulating the conservation of the species.
Anti-Microbial Activities of Turmeric and Ginger on Bacterial Isolates of Normal Skin Flora
Authors: Samuel-Penu Barisi , Baridakara Sordum Catherine
Published: April 2021

The antimicrobial activity of Zingiber officinale (Ginger) and Curcuma longa (Turmeric) was evaluated using the agar well diffusion method. Different bacterial genera (Staphylococcus Epidermis and Bacillus Sp) which were isolated from the human skin were used as the test isolates. Ginger and turmeric extracted in two different solvents, ethanol and water. Different concentrations of the extracts were prepared and directly applied against bacterial genera to reveal their antimicrobial activity. Ethanol extracts of ginger and turmeric showed greater inhibitory effect against selected Staphylococcus epidermis and Bacillus sp followed by the water extract which had the least inhibitory property. Among the two extracts, ethanol extract of ginger made higher zone of inhibition than turmeric. The overuse of this herbs should be discouraged as they could reduce the microflora of the skin thereby exposing the skin to colonization by pathogens.
Kribbella
Authors: Meyers Paul R.
Published: April 2021

Krib.bel'la. N.L. fem. dim. n.
Kribbella
arbitrary name formed from the acronym for the Korea Research Institute of Bioscience and Biotechnology (KRIBB) where taxonomic studies on this taxon were first performed.

Actinobacteria / Actinobacteria / Propionibacteriales / Kribbellaceae / Kribbella

DNA G + C content
(
mol
%): 67.0–70.6 (based on 16 type‐strain genome sequences).

Type species
:
Kribbella flavida
Park et al. 1999
VP
.
Gout, Rheumatoid Arthritis, and the Risk of Death Related to Coronavirus Disease 2019: An Analysis of the UK Biobank
Authors: Topless Ruth K. , Phipps‐Green Amanda , Leask Megan , Dalbeth Nicola , Stamp Lisa K. , Robinson Philip C. , Merriman Tony R.
Published: April 2021

Objectives

The objectives for this study were to assess whether gout and/or rheumatoid arthritis (RA) are risk factors for coronavirus disease 2019 (COVID‐19) diagnosis and to assess whether gout and/or RA are risk factors for death from COVID‐19.

Methods

We used data from the UK Biobank. Multivariable‐adjusted logistic regression was employed in the following analyses: analysis A, to test for association between gout and/or RA and COVID‐19 diagnosis (n = 473,139); analysis B, to test for association between gout and/or RA and death from COVID‐19 in a case‐control cohort of people who died of or survived COVID‐19 (n = 2059); analysis C, to test for association between gout and/or RA and death from COVID‐19 in the entire UK Biobank cohort (n = 473,139).

Results

RA, but not gout, was associated with COVID‐19 diagnosis in analysis A. Neither RA nor gout was associated with risk of death in the group diagnosed with COVID‐19 in analysis B. However, RA was associated with risk of death related to COVID‐19 by using the UK Biobank cohort in analysis C, independent of comorbidities and other measured risk factors (odds ratio [OR] 1.9; 95% confidence interval CI 1.2–3.0). Gout was not associated with death related to COVID‐19 in the same UK Biobank analysis (OR 1.2; 95% CI 0.8–1.7).

Conclusion

RA is a risk factor for death from COVID‐19 by using the UK Biobank cohort. These findings require replication in larger data sets that also allow for inclusion of a wider range of factors.
Bacterial Extracellular Vesicles and the Gut‐Microbiota Brain Axis: Emerging Roles in Communication and Potential as Therapeutics
Authors: Pirolli Nicholas H. , Bentley William E. , Jay Steven M.
Published: April 2021

Bacterial extracellular vesicles (BEVs) have emerged as candidate signaling vectors for long‐distance interkingdom communication within the gut‐microbiota brain axis. Most bacteria release these nanosized vesicles, capable of signaling to the brain via their abundant protein and small RNA cargo, possibly directly via crossing the blood‐brain barrier. BEVs have been shown to regulate brain gene expression and induce pathology at most stages of neuroinflammation and neurodegeneration, and thus they may play a causal role in diseases such as Alzheimer's, Parkinson's, and depression/anxiety. On the other hand, BEVs have intrinsic therapeutic properties that may be relevant to probiotic therapy and can also be engineered to function as drug delivery vehicles and vaccines. Thus, BEVs may be both a cause of and solution to neuropathological conditions. In this review, current knowledge of the physiological roles of BEVs as well as state of the art pertaining to the development of therapeutic BEVs in the context of the microbiome‐gut‐brain axis are summarized.
High‐Quality Translucent Alumina Ceramic Through Digital Light Processing Stereolithography Method
Authors: Sun Ying , Li Ming , Jiang Yanlin , Xing Bohang , Shen Minhao , Cao Chuanru , Wang Cao , Zhao Zhe
Published: April 2021

Herein, translucent alumina ceramics with fine complex geometric shapes are successfully fabricated by a digital light processing (DLP) process followed by vacuum sintering. The interlayer bonding condition is the key for preparing high‐quality translucent alumina for this layer‐by‐layer additive manufacturing (AM) method. The curing characteristics of alumina suspensions are carefully investigated by curing depth and polymerization conversion behavior. It is clear that the residual stress resulted from the polymerization process is more critical than the curing depth for selecting optimum curing time. Finally, high‐quality translucent alumina ceramic and complex structures are realized using this novel AM technique. It reveals that DLP 3D printing method can be a promising technology for the fabrication of transparent ceramics.
Innovation of Materials, Devices, and Functionalized Interfaces in Organic Spintronics
Authors: Li Dong , Yu Gui
Published: April 2021

Organic spintronics has been attracting the interest of the scientific community because of its potential to complement the electronics industry by combining the spin and charge degrees of freedom. Synthesized organic materials with light elements have been widely applied in organic spintronics due to their intrinsic weak spin‐orbit coupling and hyperfine interaction. Meanwhile, the prototypic devices in inorganic spintronics have been creatively utilized to fabricate analogous organic devices. The interfaces between organic materials and ferromagnetic electrodes in spintronic devices are diverse and can lead to many novel phenomena that influence the device performance. In this review, the novel organic materials, innovative devices, and functionalized interfaces in organic spintronics are comprehensively introduced. First, the fundamental concepts and parameters of organic spin devices are clarified. Subsequently, the organic materials applied in organic spintronics are classified, which include small molecules, polymers, and organic–inorganic hybrid perovskites. Moreover, several types of spin‐related devices in this field are introduced and discussed. Thereafter, the functionalized interfaces of the spin‐related devices are categorized and elaborated upon. Finally, a brief summary and future prospects are presented, which highlight the developments necessary in organic spintronics in the near future.
Realizing the Intrinsic Anisotropic Growth of 1T′ ReS2 on Selected Au(101) Substrate toward Large‐Scale Single Crystal Fabrication
Authors: Li Xiaobo , Dai Xinyue , Tang Deqi , Wang Xiao , Hong Jinhua , Chen Chao , Yang Yang , Lu Jiangbo , Zhu Jianguo , Lei Zhibin , Suenaga Kazu , Ding Feng , Xu Hua
Published: April 2021

Low‐symmetry 2D materials with strong in‐plane anisotropy are ideal platforms for building multifunctional optoelectronic devices. However, the random orientations and easy formation of multidomain structures lead to the single‐crystal synthesis of these materials remains a big challenge. Herein, for the first time, the orientation‐controlled synthesis of ReS2, a typical low‐symmetry 2D material, is explored via interface engineering based on the strong interaction between the material and Au substrates with different symmetries. It is revealed that the lattice orientation and growth behavior of ReS2 are closely relevant to the lattice symmetry of Au facets. Single crystal ReS2 domains with two and even one orientations are acquired on the four‐fold symmetry Au(001) facet and the two‐fold symmetry Au(101) facet, respectively. Combined with density functional theory calculations, it is demonstrated that the synergy of ultra‐strong ReS2‐Au interfacial coupling and reduction of symmetry of Au facet is critical to realizing its intrinsic anisotropic growth. Furthermore, great enhancement of electrical and photoelectrical performances are acquired on the well‐aligned single crystal ReS2 device. The progress achieved in this work provides significant guidance for the controllable synthesis of wafer‐scale single crystals of low‐symmetry 2D materials for their practical device applications.
Bioinspired Soft Microactuators
Authors: Zhu Pingan , Chen Rifei , Zhou Chunmei , Aizenberg Michael , Aizenberg Joanna , Wang Liqiu
Published: April 2021

Soft actuators have the potential of revolutionizing the field of robotics. However, it has been a long‐standing challenge to achieve simultaneously: i) miniaturization of soft actuators, ii) high contrast between materials properties at their “on” and “off” states, iii) significant actuation for high‐payload mechanical work, and iv) ability to perform diverse shape transformations. This challenge is addressed by synergistically utilizing structural concepts found in the dermis of sea cucumbers and the tendrils of climbing plants, together with microfluidic fabrication to create diatomite‐laden hygroscopically responsive fibers with a discontinuous ribbon of stiff, asymmetrically shaped, and hygroscopically inactive microparticles embedded inside. The microactuators can undergo various deformations and have very high property contrast ratios (20–850 for various mechanical characteristics of interest) between hydrated and dehydrated states. The resulting energy density, actuation strain, and actuation stress are shown to exceed those of natural muscle by ≈4, >2, and >30 times, respectively, and their weight‐lifting ratio is 2–3 orders of magnitude higher than the value of recent hygroscopic actuators. This work offers a new and general way to design and fabricate next‐generation soft microactuators, and thus advances the field of soft robotics by tailoring the structure and properties of deformable elements to suit a desired application.
Two‐Dimensional Metal–Organic Frameworks and Covalent–Organic Frameworks for Electrocatalysis: Distinct Merits by the Reduced Dimension
Authors: Lee Min Kyung , Shokouhimehr Mohammadreza , Kim Soo Young , Jang Ho Won
Published: April 2021

The demand to develop highly efficient electrocatalysts for renewable energy conversion has dramatically increased over the past few years. Metal–organic frameworks (MOFs) and covalent–organic frameworks (COFs) have emerged as promising materials to improve the catalytic efficiency of a variety of electrochemical energy conversion reactions. Compared to 3D bulk MOFs and COFs, which are commonly obtained by typical synthesis routes, 2D MOFs and COFs are achieved through innovative synthesis strategies, and exhibit further benefits in terms of chemical and structural properties. Specifically, the large porosity and ultrathin structure of the 2D materials contribute to exotic properties such as large surface area, mechanical flexibility, enhanced electrical conductivity, and rapid mass transport during reactions, which are highly applicable to electrocatalysis. In this review, the synthesis methods of 2D MOFs and COFs are first discussed. Then, the distinct advantages and recent advances in 2D materials for electrocatalytic reactions, including water splitting, O2 reduction reaction, CO2 reduction reaction, and N2 reduction reaction, are introduced. Finally, based on existing challenges, crucial issues for the development of reliable 2D MOFs and COFs with enhanced catalytic performance are discussed.
Tunable Interaction between Metal‐Organic Frameworks and Electroactive Components in Lithium–Sulfur Batteries: Status and Perspectives
Authors: Qi Fulai , Sun Zhenhua , Fan Xialu , Wang Zhenxing , Shi Ying , Hu Guangjian , Li Feng
Published: April 2021

Lithium–sulfur (Li–S) batteries, with high theoretical energy density, promise to be the optimal candidate of next‐generation energy‐storage. Rapid development in materials has made a major step forward in Li–S batteries. However, a big gap in cycle life and efficiency for practical applications still remains. Reasonable design of materials/electrodes a is significant aspect that must be addressed. The rising metal‐organic frameworks (MOFs) are a new class of crystalline porous organic–inorganic hybrid materials. Abundant inorganic nodes and designable organic linkers allow tailored pore chemistry at a molecular‐scale, which enables tunable interaction with electroactive components in Li–S batteries. In this review, the interaction between basic component/structure of MOFs and electroactive components in Li–S batteries is clarified to guide precise function‐driven design of MOFs. First, the reaction mechanisms and issues in Li–S batteries are briefly summarized. Second, the structural advantages of MOFs in pore chemistry and morphology are highlighted. Based on the above two aspects of understanding, a bridge between issue‐structure‐function is proposed. The interaction between MOFs with transport and reaction of electroactive components are discussed. Finally, a perspective on the future development of MOFs based materials in Li–S batteries are given. It is believed that the tunable interaction will boost the frontier interdiscipline of MOFs based electrochemical systems.