bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of innovation on the financial performance and export intensity of firms in emerging countries
Authors: Quelhas Filipe de Castro
Published: February 2022

Purpose – What impact does innovation have on the financial performance and export intensity of firms in emerging countries? Design/methodology/approach – This contribution is the result of an analysis of five years’ data (2008-2012) from a multinational survey conducted with 140 predominantly manufacturing firms from Brazil, Russia, India, China. Findings – In contrast with the prevailing literature, the results reveal strong positive correlations between the principal study variables.Originality/value – Studies of this subject have found contradictory results with regard to the effect of innovation on firm performance. Only a minority of these studies have operationalized their investigations using historical data from a range of different countries and fewer still have focused on emerging countries.This article contributes to the debate by reporting the effects of innovation activity by firms from emerging countries on their financial performance and export intensity.
Seletividade da política pública em resíduos sólidos na pandemia da covid-19: exponenciando a vulnerabilidade das cooperativas de catadores em
Authors: Santos Felipe Nepomuceno Coimbra , Borinelli Benilson , Flor Caroline Nayara Marilac , Aligleri Lilian
Published: February 2022

Objetivo: Este artigo objetivou compreender como as ações do Estado local, frente ao cenário pandêmico, produzem a seletividade estrutural no setor de Cooperativas de Resíduos face ao enfrentamento da covid-19 no Município de Londrina-PR.
Procedimentos Metodológicos: O estudo caracteriza-se como exploratório-descritivo e qualitativo, utilizando-se de dados primários e secundários extraídos, principalmente, dos questionários aplicados com representantes de cooperativas de reciclagem e de documentos oficiais. Realizamos a aplicação dos questionários com dirigentes/representantes de 6 das 7 cooperativas que possuem contrato de prestação de serviço com a Prefeitura de Londrina, entre 28 maio e 09 de junho de 2020.
Principais Resultados: A análise dos dados mostrou mecanismos combinados de seletividade estatal (estrutura, ideologia, processos e coerção) que favorecem alguns atores e dificultam o acesso a outros. A seletividade promovida pelo Estado durante a pandemia agravou a crise que já se desenvolvia localmente no setor. Embora o cooperativismo tenha sido afetado de diferentes formas, a seletividade contribui em geral para o maior desmantelamento do setor e pode até implicar na inviabilidade de algumas dessas organizações sociais.
Originalidade/Valor: O estudo possibilitou analisar a existência do conceito de seletividade do Estado, a partir de um conjunto de interesses e atores envolvidos no aparato estatal em um momento de grande crise de saúde. O estudo visa contribuir para o debate de políticas públicas e ações de enfrentamento à covid-19 em um setor considerado essencial para o bem-estar da sociedade, expondo as necessidades setoriais e ações ou inações do governo federal em seletividade estrutural.
Complexes of ellipsoids with indicatrices of coordinate vectors in the form of surfaces
Authors: Kretov M.V.
Published: February 2022

The study continues in a three-dimensional affine space of complexes of three-parameter families of ellipsoids, considered earlier in a number of works by the author. A variety of ellipsoids is studied when the ends of the coordinate vectors coincide with the focal points, and the first coordi­nate straight line describes a cylindrical surface, while on the generating element there are at least three focal points that do not lie on one straight line and on one plane passing through center, and defining three conju­gate directions. A complex of ellipsoids is distinguished from the indicat­ed manifold provided that the indicatrices of the second and third coordi­nate vectors describe surfaces with tangent planes parallel to the third coordinate plane, and the end of the second coordinate vector describes a line with a tangent parallel to the first coordinate vector. An existence theorem for the variety under study is proved. The geometric properties of the complex under consideration are found. It is proved that the end of the first coordinate vector, points of the first coordinate line, and also the first coordinate plane describe a two-parameter family of planes, the end of the third coordinate vector describes a two-parameter family of cylindrical planes, a point of the third coordinate plane describes a one-parameter family of lines with tangents parallel to the first coordinate vector. The characteristic manifold of a generating element consists of six points: the vertex of the frame, three ends of the coordinate vectors, and two ends: the sum of the first and second coordinate vectors, as well as the sum of the first and third coordinate vectors. The focal manifold of the ellipsoid, the complex under study, consists of only three points, which are the ends of the coordinate vectors.
Lie algebras of differentiations of linear algebras over a field
Authors: Sultanov A. Ya. , Glebova M.V. , Bolotnikova O.V.
Published: February 2022

In this paper, we study a system of linear equations that define the Lie algebra of differentiations DerA of an arbitrary finite-dimensional linear algebra over a field. A system of equations is obtained, which is satisfied by the components of an arbitrary differentiation with respect to a fixed basis of algebra A. This system is a system of linear homogeneous equa­tions. The law of transformation of the matrix of this system is proved. The invariance of the rank of the matrix of this system in the transition to a new basis in algebra is proved. Next, we consider the possibility of ap­plying the obtained results in differential geometry when estimating the dimensions of groups of affine transformations from above. As an exam­ple, the method of I. P. Egorov is given for studying the dimensions of Lie algebras of affine vector fields on smooth manifolds equipped with linear connections having non-zero torsion tensor fields.
Geotechnical Effects of Municipal Solid Waste Destruction with Different Compaction Methods
Authors: Jankovic Pantic Jovana , Rakic Dragoslav , Basaric Ikodinovic Irena , Djuric Tina , Hadzi-Nikovic Gordana
Published: February 2022

Disposal of waste in municipal solid waste landfills is the only way of waste disposal in Serbia, with daily compaction and covering with soil material. Due to less space for the construction of new landfills, it is necessary to use their maximum capacity. Well-compacted municipal solid waste takes up less volume and enables safer storage, so it is useful to previously determine the compaction parameters in the laboratory: maximum dry unit weight (γdmax) and optimal water content (wopt). In the practice so far, the standard method has been used to obtain these parameters (Proctor compaction test) which is common in soil mechanics. However, although this methodology has been adopted, different treatments of municipal solid waste at the landfill (including pre-treatment) indicate the need to change this classical approach. Therefore, during the research, various innovative solutions are introduced, such as the change of the classic flat Proctor hammer, by adding spikes, whose function, in addition to compaction, is partial destruction and shredding of municipal waste. In this way, the operation of compactors (hedgehogs) in the field is simulated. The paper presents the behaviour of four artificially prepared samples of municipal solid waste of different composition. The samples were tested in the standard Proctor apparatus at the same compaction energy, using different hammers, a standard flat hammer, and an innovative hammer with spikes. After that, the geotechnical effects of compaction depending on the applied approach were analyzed.
The Intermittent Fasting Revolution
Authors: Mattson Mark P.
Published: February 2022

How intermittent fasting can enhance resilience, improve mental and physical performance, and protect against aging and disease.

Most of us eat three meals a day with a smattering of snacks because we think that's the normal, healthy way to eat. This book shows why that's not the case. The human body and brain evolved to function well in environments where food could be obtained only intermittently. When we look at the eating patterns of our distant ancestors, we can see that an intermittent fasting eating pattern is normal—and eating three meals a day is not. In The Intermittent Fasting Revolution, prominent neuroscientist Mark Mattson shows that intermittent fasting is not only normal but also good for us; it can enhance our ability to cope with stress by making cells more resilient. It also improves mental and physical performance and protects against aging and disease.

Intermittent fasting is not the latest fad diet; it doesn't dictate food choice or quantity. It doesn't make money for the pharmaceutical, processed food, or health care industries. Intermittent fasting is an eating pattern that includes frequent periods of time with little or negligible amounts of food. It is often accompanied by weight loss, but, Mattson says, studies show that its remarkable beneficial effects cannot be accounted for by weight loss alone.

Mattson—whose pioneering research uncovered the ways that the brain responds to fasting and exercise—explains how thriving while fasting became an evolutionary adaptation. He describes the specific ways that intermittent fasting slows aging; reduces the risk of diseases, including obesity, Alzheimer's, and diabetes; and improves both brain and body performance. He also offers practical advice on adopting an intermittent fasting eating pattern as well as information for parents and physicians.
Inequality
Authors: Lalueza-Fox Carles
Published: February 2022

How genomics reveals deep histories of inequality, going back many thousands of years.

Inequality is an urgent global concern, with pundits, politicians, academics, and best-selling books all taking up its causes and consequences. In Inequality, Carles Lalueza-Fox offers an entirely new perspective on the subject, examining the genetic marks left by inequality on humans throughout history. Lalueza-Fox describes genetic studies, made possible by novel DNA sequencing technologies, that reveal layers of inequality in past societies, manifested in patterns of migration, social structures, and funerary practices. Through their DNA, ancient skeletons have much to tell us, yielding anonymous stories of inequality, bias, and suffering.

Lalueza-Fox, a leader in paleogenomics, offers the deep history of inequality. He explores the ancestral shifts associated with migration and describes the gender bias unearthed in these migrations—the brutal sexual asymmetries, for example, between male European explorers and the women of Latin America that are revealed by DNA analysis. He considers social structures, and the evidence that high social standing was inherited—the ancient world was not a meritocracy. He untangles social and genetic factors to consider whether wealth is an advantage in reproduction, showing why we are more likely to be descended from a king than a peasant. And he explores the effects of ancient inequality on the human gene pool. Marshaling a range of evidence, Lalueza-Fox shows that understanding past inequalities is key to understanding present ones.
Research artifacts and citations in computer systems papers
Authors: Frachtenberg Eitan
Published: February 2022

Research in computer systems often involves the engineering, implementation, and measurement of complex systems software and data. The availability of these artifacts is critical to the reproducibility and replicability of the research results, because system software often embodies numerous implicit assumptions and parameters that are not fully documented in the research article itself. Artifact availability has also been previously associated with higher paper impact, as measured by citations counts. And yet, the sharing of research artifacts is still not as common as warranted by its importance. The primary goal of this study is to provide an exploratory statistical analysis of the artifact-sharing rates and associated factors in the research field of computer systems. To this end, we explore a cross-sectional dataset of papers from 56 contemporaneous systems conferences. In addition to extensive data on the conferences, papers, and authors, this analyze dataset includes data on the release, ongoing availability, badging, and locations of research artifacts. We combine this manually curated dataset with citation counts to evaluate the relationships between different artifact properties and citation metrics. Additionally, we revisit previous observations from other fields on the relationships between artifact properties and various other characteristics of papers, authors, and venue and apply them to this field. The overall rate of artifact sharing we find in this dataset is approximately 30%, although it varies significantly with paper, author, and conference factors, and it is closer to 43% for conferences that actively evaluated artifact sharing. Approximately 20% of all shared artifacts are no longer accessible four years after publications, predominately when hosted on personal and academic websites. Our main finding is that papers with shared artifacts averaged approximately 75% more citations than papers with none. Even after controlling for numerous confounding covariates, the release of an artifact appears to increase the citations of a systems paper by some 34%. This metric is further boosted by the open availability of the paper’s text.
Micropropagation of pokeweed (Phytolacca americana L.) and comparison of phenolic, flavonoid content, and antioxidant activity between pokeweed callus and other parts
Authors: Trunjaruen Attachai , Luecha Prathan , Taratima Worasitikulya
Published: February 2022

Background

Pokeweed (Phytolacca americana L.) is regarded as an invasive plant in many parts of the world but possesses therapeutic characteristics used for antitumor and rheumatism treatment. This study investigated the effects of auxins and four explants on pokeweed callus induction. The effects of cytokinins and combinations between cytokinins and NAA on shoot and root induction were also studied. TPC, TFC and antioxidant activity of calli were screened and compared with other pokeweed plant parts.

Methods

Four explants were used to induce callus using 2,4-D and IBA at 1, 2, 3 and 4 mg/l for each auxin. Direct shoot organogenesis from nodal explants was investigated using BAP, kinetin and TDZ (1, 2 and 4 mg/l for each cytokinin). Combined effects between cytokinins and NAA at 0.1, 0.2 and 0.3 mg/l were further simultaneously estimated with root induction. Calli derived from the leaves were compared with other plant parts for TPC, TFC and antioxidant activity using the Folin-Ciocalteu, AlCl3 colorimetric assay and DPPH assays, respectively.

Results

Results showed that MS medium containing 2 mg/l 2,4-D induced callus formation on leaf explants that provided highest fresh and dry weights. Three types of synthetic cytokinins as kinetin, TDZ and BAP were used for direct shoot organogenesis from pokeweed nodes. MS medium containing 2 mg/l kinetin was effective in stimulating normal shoots, with the largest number of shoots and leaves and the longest shoots. The combination between cytokinins and NAA showed no positive effect on shoot and root induction from pokeweed nodal explants. For TPC and TFC determination, pokeweed seeds and leaves possessed the highest phenolic and flavonoid contents, respectively. Highest phenolic content of pokeweed seeds led to lowest IC50 by DPPH assay. Phenolic content was higher than flavonoid content.

Conclusion

Results suggested promising conditions for callus induction. Leaf explants cultured on MS medium with 2 mg/l 2,4-D and nodal explants cultured on MS medium with 2 mg/l kinetin provided the largest number of normal shoots and leaves. NAA did not show positive effects on shoot and root induction when combined with cytokinins. Chemical constituent screening indicated that seeds and leaves provided highest TPC and TFC, respectively, while pokeweed calli contained higher phenolic than flavonoid content. This is the first report describing chemical constituent screening and antioxidant activity of calli and other parts of the pokeweed plant. Results provided significant information to further enhance bioactive compound contents of pokeweed calli using elicitation methods.
Knowledge and Practice of Personal Protective Equipment among Students of Different Healthcare Specialties during COVID-19 Pandemic
Authors: Khan Siraj DAA , Al-Garni Musleh , Alalharith Abdullrahman Saeed Hadi , Alalharith Mohammad Dafer , Obaid Obaid Saleh , Baaltahin Saleh Saeed AL , Alnaji Mohammad Abdulkareem
Published: February 2022

Introduction: Healthcare professionals who are constantly working to treat the patients of Coronavirus Disease-2019 (COVID-19) are at great risk. So the only method they can prevent themselves while working is the use of Personal Protective Equipment (PPE). The use of PPE has increased with the spread of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). Aim: To evaluate the knowledge and practice of students of different healthcare specialties regarding the use of PPE. Materials and Methods: The present cross-sectional study was conducted from October 2020 to December 2020 on healthcare students of different healthcare specialties of Najran University, Saudi Arabia. Participants were asked questions about the practice and knowledge of PPE via an electronic link of a questionnaire. Collected data were statistically analysed for frequency and association of responses by using Statistical Package for the Social Sciences (SPSS) version 23.0. Results: Total of 606 students (females were 122, males were 484) from different health specialities i.e., Medical (25.4%), Dental (42.1%), Pharmacy (11.2%), Nursing (13.4%) and Physiotherapy (7.9%) participated in this survey. Most of the participants (110 from the medical field, 142 from dental, 42 from pharmacy and 63 from nursing and 28 from physiotherapy) were familiar with the word PPE before this pandemic. There was a significant relationship (p-value <0.0001) between the specialty and practice of PPE. The majority of the participants (52%) did not know the Occupational Safety and Health Administration (OSHA) guideline and 55.9% were not aware of donning and doffing. Only 44.7% of professionals used N95 before the pandemic and 41.9% did not use N95 before COVID-19. While using the N95 mask 58.2% felt comfortable and 11.4% didn’t feel comfortable and the remaining participants were not sure. Conclusion: Although most participants practiced and had knowledge about the use and handling of PPE, but still there is a need to improve their knowledge and train them about its importance during COVID-19. Their knowledge can be improved by different training programs and health education.
Bilateral Long Standing Exudative Retinal Detachment in Coat's Disease
Authors: Sodhi Punita Kumari
Published: February 2022

Purpose:

Coat's disease presents with an exudative retinal detachment at an early age. However, bilateral involvement is uncommon. We present a case with bilateral long standing retinal detachment (RD) in Coat's disease.

Methods:

An 18 years old male having progressive diminution of vision from last six years had visual acuity of logmar 1.77 and 1.47 in the right eye (RE) and left eye (LE) respectively with poorly dilating pupils in both eyes. He did not have any systemic abnormality. We did a detailed fundus examination along with fundus fluorescein angiography (FFA) and OCT.

Result:

The fundus examination showed subretinal exudates with demarcation line above long standing infero-temporal RD in RE. The LE had a self-settled RD with an atrophic temporal retina having macrocysts. There was no proliferative vireo-retinopathy (PVR) in either eye. The fundus fluorescein angiography (FFA) showed leaks at the exudates in RE and leak at the optic disc in LE. The optical coherence tomography (OCT) showed RD in RE and self-settled RD with subretinal exudate in LE.

Conclusion:

The manuscript shows a bilateral long-standing exudative RD in Coat's disease with associated features like subretinal exudates showing leaks in angiography, demarcation line, macrocysts, retinal atrophy with underlying choroidal flush, absence of PVR and self-settlement of RD.
UBM Imaging
Authors: Viswanath Shweta , Gupta Shikha
Published: February 2022

Ultrasound biomicroscopy is a non-invasive modality of imaging used for visualization of anterior ocular structures that are obscured by the normal as well as pathological relations. This article gives an overview of the imaging technique and its application in ophthalmology.
Hurricane Keratopathy – “A Curlicue on The Cornea”
Authors: Gonugunta Vishnu Teja , Muthaiah Srinivasan
Published: February 2022

Hurricane keratopathy is seen in the corneas with exaggerated epithelial cell turnover. It represents the path of proliferating epithelium visible by collection of pigment or iron within the corneal epithelium. It should be differentiated from cornea verticillata. Hurricane keratopathy is highlighted with fluorescein staining and not associated with drug deposition within the epithelium. Acute postoperative corneal steepening due to the surgical induced astigmatism causing decreased wetting of the cornea in addition to healing epithelial defect could be the cause of hurricane keratopathy appearance. Hurricane resolves once the stimulus for rapid epithelial turnover is eliminated.
Consumer Purchase Intention the Products of Small and Medium Enterprises (MSMEs) in the Province of West Nusa Tenggara
Authors: . Zulkieflimansyah , Nurjihadi Muhammad , Santoso Agus , Maradita Fendy , . Hartini
Published: February 2022

This study determines the effect of trust, product quality, and perception on consumer purchase intention in micro and medium-sized products (MSMEs) included in the JPS Gemilang program. This research is a quantitative study. With a sample size of 100. they were using the structural equation modeling (SEM) data analysis method. The results showed that the trust variable had no significant effect on consumer buying interest. In contrast, the price perception and product quality variables significantly affected consumer purchase intention. Quality products accompanied by affordable prices will attract consumers to buy MSME products. The COVID-19 pandemic has caused people to save money in spending their money and tend to buy primary and health needs. Therefore, it is essential to increase consumer buying intention so that consumers are interested in buying products.
Enteric Fever Pattern among Patients Attending General Hospital Kaltungo
Authors: Peters Emmanuel , Muhammed Nuhu , Maori Lynn , Haruna Maikudi , Umar Zainab , C. Mamtara Rimamnyang , David Awak Samirah , Damuut David Peter
Published: February 2022

Salmonella typhi and Salmonella paratyphi causes typhoid and paratyphoid fevers respectively. Out of the one thousand two hundred and six (1206) sample analyzed for Typhoid and Paratyphoid fevers using tile method; 748 (62.0%) were positive while 458 (38%) were negative. Females were found to have the highest positivity rate of 413 (68.4%), while males had 335 (55.5%) positivity rate. The age bracket with the highest positivity rate 0-10years and above (28.3%), followed by 11-20years (26.2%). The age bracket with the lowest percentage positivity was 60years and above (6.0). We therefore wish to conclude that women should take personal hygiene serious and people from the following age groups of 0-10years and those at age 11-20 regardless of their sex should do likewise as Salmonellosis was found to be high among those categories of people.
The Importance of Monoterpenes in the Antibacterial Activity of Osteophloeum platyspermum Essential Oils
Authors: De Sousa Sinária R. N. , S. Silva Jefferson de , Paciencia Mateus L. B. , Frana Sergio A. , C. Díaz Ingrit E. , Suffredini Ivana B.
Published: February 2022

Aims: To evaluate antibacterial and cytotoxic activities of essential oils (EO’s) obtained from Osteophloeum platyspermum (ucuuba-chico-de-assis; Myristicaceae) fresh leaves against Staphylococcus aureus, MCF-7 breast, and PC-3 prostate cancer cell lines.

Study Design: Thirteen EO's were submitted to antibacterial and cytotoxicity assays that included 18 compounds commonly present in the EO's. The relationship between the EO's biological activities and the dry (DS) or rainy (RS) seasonal variation was accessed using the relative percentage of the terpenes.

Place and Duration of the Study: The study was conducted at the Center for Research in Biodiversity (Microbiology Laboratory and Cell Culture Laboratory), Paulista University. Biological activity assessment was conducted between October/2016 and November 2019).

Methodology: Thirteen essential oils were obtained from the leaves of O. platyspermum and were previously chemically characterized. From the analyses, 18 terpenes were determined to commonly occur in the 13 EO's. Microdilution broth and cytotoxicity assays were performed to obtain minimal bactericidal concentrations (MBCs) and 50% (EC50) effective concentrations for the cytotoxicity assays. Data from the 18 terpenes were submitted to two-way ANOVA, cluster (CA), principal component (PCA), canonical correspondence analyses (CCA), and one-sample t-test. The relationship between the biological activities of EO's and seasonal variability (dry season, DS, or rainy season, RS) was assessed. One sample t-test was performed to verify the potency of the cytotoxic effects of EO’s.

Results: Previously, 18 terpenes were identified in all the 13 EO’s. From those, α-terpineol, limonene, myrcene, linalool, and terpinen-4-ol were relevant to the ordination of the DS EO set, while spathulenol, α-pinene, β-pinene, isospathulenol, α-cadinene, ledol, cubenol-1-epi, neo-intermedeol, elemol, β-elemene, γ-elemene and viridiflorol were relevant to the ordination of the RS EO set. The biological activities were more related to the EO’s collected in the RS than those in the DS. Also, biological activities were shown to be related to the occurrence of limonene, myrcene, elemol, β-pinene, α-pinene, and terpinen-4-ol.

Conclusions: Although the presence of the 18 terpenes is necessary to maintain the species adaptability to the environment, the occurrence of limonene, myrcene, elemol, β-pinene, α-pinene, and terpinen-4-ol had a significant role in the effective expression of the biological activity of EO’s from O. platyspermum, particularly those that occur during the rainy season, in the Amazon rain forest.
Prevalence of Staphylococcus aureus and Staphylococcus sciuri Isolated from Apparently Healthy and Hospitalized Patients in Ekiti State, Nigeria
Authors: Ogunfolakan O. O. , O. A. Olowe , Taiwo S. S. , Daramola G. O. , Bamigboye B. T. , Egbebi A. H. , Okunlola A. T. , Olaniyan A. M.
Published: February 2022

The emergence of microbial resistance to antibiotics on daily basis has become a major global challenge. The increasing prevalence of methicillin resistant Staphylococcus aureus (MRSA) infections among hospitalized and non-hospitalized patients due to emergence of unique community-associated strains has become a great problem in Nigeria in particular and the entire world in general. In this study, a total of four hundred (400) clinical specimens were collected from hospitalized patients at Ekiti State University Teaching Hospital (EKSUTH), Ado-Ekiti and Federal Teaching Hospital (FETHI), Ido-Ekiti and from apparently healthy individuals from both communities. Standard bacteriological procedures were employed to isolate and identify these organisms. Antibiotic susceptibility test was carried out using the modified Kirby Bauer disc diffusion method. Polymerase chain reaction (PCR) assay was used to identify S. aureus nuc gene, as well as mecA and aac resistance genes. Seventy seven (19.3%) S. aureus isolates were phenotypically identified; 43 (21.5%) hospital-associated (23 from EKSUTH and 20 from FETHI) and 34 (17.0%) community-associated (27 from Ado-Ekiti and 7 from Ido-Ekiti communities). No S. sciuri was phenotypically isolated in both locations.  Fifty five (71.4 %) of the 77 S. aureus isolates were nuc gene positive, while 11 (20%) of the 55 isolates were mecA gene positive, implying that they were MRSA. Of the 11 isolates, 6 (19.4%) were hospital-associated MRSA while 5 (20.8 %) were community-associated MRSA. Phenotypic resistance of S. aureus to cefoxitin in the two locations ranged between 77.8 – 100%, but 80% of cefoxitin-resistant nuc gene positive S. aureus lacked mecA gene. S. aureus isolates exhibited high phenotypic resistance to tetracycline, erythromycin and fusidic acid but susceptible to clindamycin and gentamycin. The prevalence of clinical MRSA infection of 20% in this study is relatively high. However, there was 0% prevalence of S. sciuri colonization. Cefoxitin disc test demonstrated low specificity as a phenotypic marker of methicillin resistance.There is need to institute control measures for MRSA infections and colonization in this environment.
Assessment of Nutritional Status among Male and Female Undergraduate Students of Saveetha Dental College
Authors: Raj M. Preethi , Priya A. Jothi , Devi R. Gayatri
Published: February 2022

A rational way of nourishment, combined with adequate physical activity, are the basic components of maintaining proper body condition. The aim of the study was to evaluate nutritional status among male and female undergraduate students of Saveetha dental college.  A cross sectional survey of different questions, dietary patterns was conducted with a sample of 184 students (I, II, III, IV, and V students). Survey was conducted via google form through random sampling to identify undernutrition in the sample. Questionnaires were based on dietary health patterns and nutritional status in day to day life. The sample size for this study is about 184 participants and at the end of the survey, all the data were collected and analysed by using IBM SPSS software. The results obtained was the majority of the students are at normal weight and the scores met optimal levels. This suggests good quality and quantity of diet.
A Study on the Data Quantification of Weapon System RAM Objective Setting Using Evidence Theory
Authors: Na Il Yong
Published: February 2022

When setting the RAM objectives, various data such as expert opinions and the historical data of similar types of equipment are used. However, many times subjectivity is involved in the process of merging and utilizing data, and there are many cases where some information is omitted or an ambiguous method is used. Most of the previous work focused only on the process or method of calculating values using well-organized data rather than manipulating raw data. But if the data manipulation process is not objective, it is difficult to guarantee the accuracy of the results even if the calculation logic and method are accurate. This study proposes a systematic data merging process used to set the RAM objectives using the evidence theory. The proposed method can be used to avoid information loss and merge the data objectively. Moreover, contribute to improving the accuracy of setting the RAM objectives in the future.
Colossal Barocaloric Effect in Carboranes as a Performance Tradeoff
Authors: Zhang Kun , Song Ruiqi , Qi Ji , Zhang Zhe , Zhang Zhao , Yu Chenyang , Li Kuo , Zhang Zhidong , Li Bing
Published: February 2022

The discovery of colossal barocaloric effects in organic plastic crystals has significantly advanced the development of solid‐state refrigerant techniques. Adapting to the real application, a tradeoff of various barocaloric performances has to be achieved. Here, it is reported a novel plastic crystal system, that is, carboranes (C2B10H12), including three positional isomers: ortho‐carborane, meta‐carborane, and para‐carborane, which are characterized by C2v, C2v, D5d point groups, respectively. They all undergo an orthorhombic‐to‐tetragonal phase transition around room temperature. Compared to the previously reported organic plastic crystals, this system exhibits a combination of large pressure‐normalized entropy changes, the high‐pressure sensitivity of the transition temperature, small thermal hysteresis, and so forth. Their barocaloric performances are positional‐isomerism dependent, and the best performances are obtained in para‐carborane with maximum entropy changes of about 106.2 J kg−1 K−1 achieved under pressure changes below 30 MPa. This study not only suggests that carboranes would be a considerably promising working material for barocaloric refrigeration at room temperature but also indicates that delicate tuning of molecular isomerism is an effective strategy to enhance barocaloric performances.
Superlubricity Enabled by Load‐Driven Redistribution of Electrons
Authors: Cheng Ziwen , Sun Junhui , Zhang Bozhao , Lu Zhibin , Ma Fei , He Qi‐Chang
Published: February 2022

By first‐principles calculations, it is shown that the friction at solid‐solid interfaces between 2D nanomaterials (TDNMs), such as h‐BN and graphene, can be reduced nearly to zero even if the normal load is smaller than 5 GPa. The quantitative analysis of interfacial charge density demonstrates a detailed process in which the pressure‐driven redistribution of electrons alters interlayer coupling of TDNMs and that reveals the electronic‐scale mechanism of pressure‐tunable lateral sliding at 2D commensurable interfaces. The shift of interlayer interaction results in sliding potential energy surface (PES) from a corrugated state to a flattened one and, eventually, to a counter‐corrugated one as the load increases. The flattened PES at new critical load implies the absence of any energy dissipation during interfacial sliding, i.e., the occurrence of superlubricity during interfacial sliding. These results also give rise to a quantitative model for the load‐dependent behavior of nano‐friction and promote the critical condition of the low‐pressure‐induced superlubricity to an experimentally feasible range.
Interfacial Assembly of Functional Mesoporous Carbon‐Based Materials into Films for Batteries and Electrocatalysis
Authors: Xu Hongbin , Li Haozhe , Xie Lei , Zhao Dongyuan , Kong Biao
Published: February 2022

The rapid increase in energy demands and environmental issues have attracted tremendous attention in the development of new functional materials for sustainable energy technology. As an emerging materials class, mesoporous carbon‐based films show unique properties, and have been regarded as a promising candidate in efficient energy storage and conversion applications. Interfacial assembly strategies are usually employed to construct such films and devices. In this review, the recent development in the synthesis of mesoporous carbon‐based films and devices is illustrated through interfacial assembly strategies. For mesoporous carbon‐based materials, template methods and template‐free methods are the two common approaches to obtain these unique structures. More specifically, five primary interfacial assembly methods for film preparation, including flow‐directed assembly, solvent casting assembly, electrospinning assembly, substrate‐based assembly, and evaporation‐induced self‐assembly, are also discussed with detailed synthesis processes and mechanisms. Besides, the applications of mesoporous carbon‐based film devices for electrochemical energy systems including batteries and electrocatalysis are reviewed, as well as their mechanisms to enhance the performance of these systems. Finally, the remaining challenges and outlook are proposed to inspire future development and contribution of this field.
Designing Strong Interface of Cubic‐like Sn–Co–S@carbon with SnO2 as Catalyst for Enhanced Li/Na‐Ion Storage Abilities
Authors: Dong Yu , Qi Yueheng , Zhao Wenqing , Yuan Shaohui , Zeng Zihao , Yang Yue , Sun Wei , Ge Peng
Published: February 2022

As potential candidates, metal sulfides display strong storage abilities but suffer from serious volume swelling and polysulfide shuttling. Especially rich‐sulfur materials, inferior reversible conversion reactions (from MS2 to MS with S) can bring about major formation of sulfur. Herein, cubic‐like Sn–Co–S materials with SnO2 as catalyst are designed with various dimensional carbon. The as‐resulted samples display uniform distributed particle size (≈5 µm), while cross‐linked Sn–Co–S@carbon is successfully formed due to its rich surficial groups. Significantly, the formation of chemical bonds about Sn/Co–S–C is noted, facilitating ions/e‐transfering and architecture enhancing. Meanwhile, owing to the endothermic effect of carbon, SnO2 finally resulted, effectively limiting the so‐called “shuttling effect” of polysulfide. Utilized as sodium‐ion anodes, the optimized samples can deliver a capacity of 490 mAh g−1 at 0.5 A g−1 and ≈400 mAh g−1 above at 5.0 A g−1. Assisted by the detailed kinetic analysis, it can be confirmed that the improvements of surface‐controlling behaviors mainly come from the interfacial chemical bonds and strong‐polar metal‐oxides bonds. This work is expected to illustrate the roles of interfacial design and metal oxide catalysts for advanced energy storage materials.
Electrochromic 2,5‐Dihydroxyterephthalic Acid Linker in Metal−Organic Frameworks
Authors: Shiozawa Hidetsugu , Melnikova Zuzana , Bastl Zdenek , Peterlik Herwig , Kalbac Martin , Frank Otakar
Published: February 2022

Metal–organic frameworks (MOFs) are diverse in color owing to a large variety of molecular structures. Herein, electrochromism of M‐MOF‐74 (M = Mg, Mn, Co or Zn) is reported, which is a honeycomb nano‐framework in which hexagonally packed 1D arrays of metal cations are coordinated with 2,5‐dihydroxyterephthalic (dhtp) acid linker. Raman spectroscopy upon electrochemical doping combined with density functional theory calculations reveals redox reactions of the linker while the metal cations stay divalent as probed by X‐ray photoemission spectroscopy (XPS). Excellent adhesion of the MOFs to glass allows the synthesis of quality thin films to be implemented into electrochromic devices that exhibit promising color contrast and durability.
Understanding Robustness of Magnetically Driven Helical Propulsion in Viscous Fluids Using Sensitivity Analysis
Authors: Venezian Roberto , Khalil Islam S. M.
Published: February 2022

Magnetically‐actuated helical microrobots can propel themselves in fluids and tissues‐like mediums with a wide range of Reynolds numbers (Re). The properties of physiological fluids and input parameters vary in time and space and have a direct influence on their locomotion along prescribed paths. Therefore, understanding the response of microrobots to variations in rheological properties and input parameters become increasingly important to translate them into in vivo applications. Here, a physical framework is presented to understand and predict key parameters whose uncertainty affect certain state variables most. A six‐degree‐of‐freedom magneto‐hydrodynamic model is developed based on the resistive force theory (RFT) to predict the response of robots swimming through different fluids and examine their response during transitions into Newtonian–viscoelastic interfaces. Performance of the robot, while swimming in a fluid with a fixed viscosity, is quantified using sensitivity analysis based on the magneto‐hydrodynamic model. The numerical results show how abrupt changes in viscosity can affect their ability to rotate with the rotating field in synchrony. The sensitivity analysis shows that the states of the robot are mostly sensitive to variations in the actuation frequency. Open‐loop experiments are performed using a permanent‐magnet robotic system comprising a robotic arm and a rotating permanent magnet to actuate and control a helical robot at the Newtonian–Viscoelastic interface and validate the theoretical predictions of the RFT‐based sensitivity analysis.
“It's a place to feel like part of the community”: Counterspace, inclusion, and empowerment in a drop‐in center for homeless and marginalized women
Authors: Toolis Erin , Dutt Anjali , Wren Alexander , Jackson‐Gordon Rachel
Published: February 2022

In the context of rising inequality and eroding safety nets for marginalized communities, research is needed to demonstrate the ways in which settings can facilitate community, agency, and capabilities for low‐income women. The purpose of this study is to examine if and how an organizational setting designed to support homeless, low‐income, and other marginalized women can facilitate empowering changes and increased wellbeing among the women who participate. A thematic analysis of interviews conducted with 22 participants who attend a women's day center identified three ways in which the organizational setting impacted women's lived experiences: (a) increasing a sense of agency through acceptance, active and participatory roles, and ownership over the physical environment, (b) promoting a sense of community through rituals of care and attentiveness, alleviated social isolation, and mutual relationships, and (c) improving life circumstances by offering a safe environment, access to basic resources such as housing, and support for health and wellbeing. Findings highlight the setting features and psychosocial processes that foster flourishing and resist patterns of exclusion and devaluation imposed on marginalized women by dominant neoliberal values, institutions, and policies.
Refining reproductive risk for FMR1 premutation carriers in the general obstetric population
Authors: Owens Kailey M. , Terhaar Catherine , Zdrodowski Jamie , Johnson Lisa R. , Eveleigh Deepa
Published: February 2022

Female FMR1 premutation (FMR1 PM) carriers for fragile X syndrome (FXS) are at risk to have a child with FXS based on their CGG repeat size and AGG interruption number. Studies examining this risk in unselected populations of female PM carriers are lacking. This retrospective cohort study analyzed carrier status, CGG repeat length, AGG interruption result, and reproductive risk refinement in a population of female patients who underwent routine carrier screening for FXS. A total of 1536 PM carriers (0.43%) were identified, 95% of whom had between 55 and 90 CGG repeats. A number of 1334 carriers underwent AGG interruption testing. The majority had at least one AGG interruption and received a lower reproductive risk for FXS following AGG interruption testing (89% and 85%, respectively) as compared to their risk calculated based on CGG repeat size alone. The average change in risk across the population following AGG interruption testing was −3.4%, with a range from −50.8% to 48.9%. This article describes the range of CGG repeats and AGG interruptions in an unselected population of female PM carriers and suggests that most carriers would benefit from AGG interruption testing to refine their reproductive risk of having a child with FXS.
Visible‐Light‐Driven Photocatalytic CO2 Reduction to CO/CH4 Using a Metal–Organic “Soft” Coordination Polymer Gel
Authors: Verma Parul , Rahimi Faruk Ahamed , Samanta Debabrata , Kundu Arup , Dasgupta Jyotishman , Maji Tapas Kumar
Published: February 2022

The self‐assembly of a well‐defined and astutely designed, low‐molecular weight gelator (LMWG) based linker with a suitable metal ion is a promising method for preparing photocatalytically active coordination polymer gels. Here, we report the design, synthesis, and gelation behaviour of a tetrapodal LMWG based on a porphyrin core connected to four terpyridine units (TPY‐POR) through amide linkages. The self‐assembly of TPY‐POR LMWG with RuII ions results in a Ru‐TPY‐POR coordination polymer gel (CPG), with a nanoscroll morphology. Ru‐TPY‐POR CPG exhibits efficient CO2 photoreduction to CO (3.5 mmol g−1 h−1) with >99 % selectivity in the presence of triethylamine (TEA) as a sacrificial electron donor. Interestingly, in the presence of 1‐benzyl‐1,4‐dihydronicotinamide (BNAH) with TEA as the sacrificial electron donor, the 8e−/8H+ photoreduction of CO2 to CH4 is realized with >95 % selectivity (6.7 mmol g−1 h−1). In CPG, porphyrin acts as a photosensitizer and covalently attached [Ru(TPY)2]2+ acts as a catalytic center as demonstrated by femtosecond transient absorption (TA) spectroscopy. Further, combining information from the in situ DRIFT spectroscopy and DFT calculation, a possible reaction mechanism for CO2 reduction to CO and CH4 was outlined.
Zeitaufgelöste In‐Situ‐Untersuchungen von mechanochemischen Reaktionen
Authors: Michalchuk Adam A. L. , Emmerling Franziska
Published: February 2022

Mechanochemische Umwandlungen bieten umweltfreundliche Synthesewege und verbessern gleichzeitig die Geschwindigkeit und Selektivität von Reaktionen. Mechanochemie ermöglicht es, die Art und Weise, wie die Chemie in der Wissenschaft und in der Industrie betrieben wird, zu verändern, wird aber durch das mangelnde mechanistische Verständnis stark behindert. Die kontinuierliche Entwicklung und Anwendung von zeitaufgelösten In‐situ‐Methoden (time‐resolved in situ TRIS) zur Überwachung mechanochemischer Reaktionen bietet eine neue Dimension zur Erforschung dieser faszinierenden Umwandlungen. Wir diskutieren hier die jüngsten Trends in der Methodenentwicklung, die die Grenzen der mechanochemischen Forschung erweitert haben. Anschließend werden neue Merkmale mechanochemischer Reaktionen, die mit TRIS‐Techniken gewonnen wurden, erörtert, und es wird beleuchtet, wie verschiedene TRIS‐Ansätze verwendet wurden. Der Schwerpunkt liegt dabei auf der Stärke der Kombination komplementärer Techniken. Abschließend wird das Potenzial von TRIS‐Methoden in der mechanochemischen Forschung für die Etablierung eines neuen, umweltfreundlichen Paradigmas in den chemischen Wissenschaften dargestellt.
Controlled Disassembly of Elemental Sulfur: An Approach to the Precise Synthesis of Polydisulfides
Authors: Chao Ji‐Yan , Yue Tian‐Jun , Ren Bai‐Hao , Gu Ge‐Ge , Lu Xiao‐Bing , Ren Wei‐Min
Published: February 2022

The usage of elemental sulfur (S8) for constructing sulfur‐containing polymers is of great significance in terms of sulfur resource utilization or fabrication of high‐performance polymers. Currently, the random disassembly of S8hinders its direct use in the precise synthesis of sulfur‐containing polymers. Herein, we provide an effective strategy for controlling the dismantlement of S8to synthesize polydisulfides, a promising category of dynamic bonds containing polymers. In this strategy, the completely alternating copolymerization of one sulfur atom, which is orderly derived from S8, with episulfides is achieved with MTBD (7‐methyl‐1,5,7‐triazabicyclo[4.4.0]dec‐5‐ene) as catalyst and [PPN]SbF6([PPN]+is bis(triphenylphosphine)iminium) as cocatalyst. Delightedly, the living‐ polymerization feature, and the good monomer compatibility allows for the access to diverse polydisulfides. Furthermore, the density functional theory (DFT) was employed to elaborate the copolymerization process.
Wrinkled Titanium Carbide (MXene) with Surface Charge Polarizations through Chemical Etching for Superior Electromagnetic Interference Shielding
Authors: Ying Mengfan , Zhao Rongzhi , Hu Xin , Zhang Zhenhua , Liu Weiwei , Yu Jieyi , Liu Xiaolian , Liu Xianguo , Rong Huawei , Wu Chen , Li Yixing , Zhang Xuefeng
Published: February 2022

Despite the fact that the high conductivity of two‐dimensional laminated transition metal carbides/nitrides (MXenes) contributes to the outstanding electromagnetic interference (EMI) shielding by the reflection of electromagnetic waves (EWs), it is difficulty to improve EMI shielding by pursuing higher conductivity due to the limitation of intrinsic properties. Here, we achieve superior EMI shielding by introducing the absorption of EWs in MXenes with micro‐sized wrinkles which are induced by abundant Ti vacancies under chemical etching. The shielding effectiveness is up to 107 dB at a thickness of 20 μm. Combining with atomic‐scale structure observation and the first‐principles calculations, it is concluded that the promotion of EMI shielding originates from the resonant absorption of formed electric dipoles induced by the asymmetrical distribution of charge densities near Ti vacancies. Our results could open a new vista for developing two‐dimensional EMI shielding materials.