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An experiment in teaching students to use the literature to devise and defend a plan for novel research is presented as part of a graduate-level course in heterocyclic chemistry. Students in three successive iterations of the course completed an assignment during which they were assigned novel heterocyclic cores that were selected by varying or relocating the heteroatoms of a known drug. They were then asked to identify potential research areas related to their assigned cores and to determine whether the structures containing these cores were likely to have practical applications. The students presented their results as though they were a collaborative research group in an industrial setting requesting funding for future research. A full description of the assignment and a summary of the student outcomes and ideas for future development are discussed.

Phase retrieval occurs in many research areas. There are some classical phase retrieval methods such as hybrid input-output (HIO) and difference map (DM). However, phase retrieval results are sensi...

This paper represents a new mathematical model for helicopters with flexible fuselages. The theory connects the two commonly separated research areas of flight, dynamics and structural dynamics, by...

Machine learning plays a vital role in construction industry which could make improve project’s safety, productivity, and quality. Many studies have attempted to explore the potential opportunities to adopt this technology in different aspects of the construction sector. However, no comprehensive study to review the global research trends on this technological advancement in construction management domain. The goal is to investigate and summarize the state-of-the-art knowledge body in this topic in a systematic manner. To achieve this, this paper considered 161 studies on machine learning in construction management related to bibliographic records retrieved from the Scopus database by adopting scientometric analysis approach. This paper found that since 2014, there has been a considerable increase in the number of publications on this domain. Researchers from the United States, China, and Australia have been the main contributors to this research area through regional analysis. This study also revealed that approximately 34% of all countries in the world are engaged in this domain research. In addition, five main aspects in construction management have been applied machine learning techniques, namely, assess and reduce risk, safety management for construction sites, cost estimation and prediction, Schedule management, and building energy demand prediction. Furthermore, three potential construction management research areas that can apply this technology were proposed for further studies. The findings will help both professionals and researchers more understanding how machine learning knowledge is evolving and its role played in the construction management domain, and this study thus offers a useful reference point to how can develop this area in the future.

Scientists may shift research interests and span multiple research areas in their careers, reflecting the research diversification of scientists. Quantifying the scientists’ research diversity can help to understand the research patterns of scientists. In this paper, we study the research diversification of scientists in Physics based on the Physics and Astronomy Classification Scheme (PACS) which can well reflect the research topics of physics papers. For each scientist, we first build a PACS codes co-occurrence network and reveal the research diversity by analyzing the connectivity and community structure of this network. Then we use diversity indicators to measure the research diversification of scientists and analyze the distribution of each indicator. Finally, we investigate the relationship between scientists’ diversity indicators and their scientific impact using multiple regression analysis. The results show that the numbers of connected components of most PACS codes co-occurrence networks are less than 5, and some networks have significant community structures. The diversity indicators show the heterogeneity of the research diversity of physicists. We also find that some diversity indicators are weakly correlated with scientific impact indicators. Based on our findings, we suggest that physicists should focus on their main research fields and span multiple research fields over their entire careers which could promote their scientific impact.

Recent advances in nanotechnology have attracted significant attention to nanodiamonds (NDs) in both industrial and research areas thanks to their remarkable intrinsic properties: large specific area, poor cytotoxicity, chemical resistance, magnetic and optical properties, ease of large-scale production, and surface reactivity make them suitable for numerous applications, including electronics, optics, sensors, polishing materials, and more recently, biological purposes. Growing interest in diamond platforms for bioimaging and chemotherapy is observed. Given the outstanding features of these particles and their ease of tuning, current and future applications in medicine have the potential to display innovative imaging applications and to be used as tools for monitoring and tracking drug delivery in vivo.

The papers in this special section focus on nanobiophotonics. This is an emerging field of modern science and biomedical nanotechnology. This new field continues to vastly expand with state-of-the-art developments across the entire spectrum of biomedical applications ranging from fundamental studies of light-nanobiomaterial interactions to clinical diagnostics and therapeutics. In nanobiophotonics research areas, there has been a great impetus recently for the development of noninvasive imaging and sensing of intracellular structures and cellular functions as well as obtaining quantitative information for light-tissue interactions at the cellular, intracellular, and molecular level. Existing photonics technologies provide unique capabilities for investigating these scientific questions in terms of using non-ionizing optical radiation for providing noninvasive intracellular, cellular, and tissue imaging, and in-vivo sensing with ultrahigh resolution in the subwavelength nanoscale range (smaller than 100 nm). Furthermore, recent technology development efforts leverage the advanced features of photonics to move beyond the diffraction limit, providing sub-nanometer resolution into cellular processes.

During the past half century, the study of social contention has been characterized by a division between research on labor movements and studies on other social movements. This division also left its mark on the study of modes of action: while labor scholars mainly examined strikes, social movement scholars have increasingly come to focus on street protests. This article is a contribution to bridging the gap between the two research areas both on theoretical and empirical levels. On a theoretical level, I discuss the usefulness of combining economic and political models of contention from the two research areas. On an empirical level, I use official data provided by Spanish ministries to examine and relate the workers’ use of strikes and street protests between 2000 and 2016 in Spain. Examining strikes and street protests jointly does not only provide a fuller picture, it also helps to discern contrasts and thus the specificities of each mode of action. En el último medio siglo, los estudios del conflicto social se han caracterizado por una separación entre investigaciones sobre movimientos laborales y estudios sobre otros movimientos sociales. Esta división también dejó su marca en el estudio de los modos de acción: mientras que las sociólogas y los sociólogos del trabajo examinaban principalmente las huelgas, las y los especialistas en movimientos sociales se han centrado cada vez más en las protestas callejeras. Este artículo es una contribución para cerrar la brecha entre las dos áreas de investigación tanto a nivel teórico como empírico. A nivel teórico, se discute la utilidad de combinar modelos económicos y políticos del conflicto social de las dos áreas de investigación. A nivel empírico, se utilizan datos oficiales proporcionados por ministerios españoles para examinar y relacionar el uso de huelgas y manifestaciones callejeras por parte de los trabajadores entre 2000 y 2016 en España. El examen combinado de las huelgas y las protestas callejeras no sólo proporciona una imagen más completa, sino que también ayuda a discernir los contrastes y, por lo tanto, las particularidades de cada modo de acción.

Molecular photoswitches enable dynamic control of processes with high spatiotemporal precision, using light as external stimulus, and hence are ideal tools for different research areas spanning from chemical biology to smart materials. Photoswitches are typically organic molecules that feature extended aromatic systems to make them responsive to (visible) light. However, this renders them inherently lipophilic, while water-solubility is of crucial importance to apply photoswitchable organic molecules in biological systems, like in the rapidly emerging field of photopharmacology. Several strategies for solubilizing organic molecules in water are known, but there are not yet clear rules for applying them to photoswitchable molecules. Importantly, rendering photoswitches water-soluble has a serious impact on both their photophysical and biological properties, which must be taken into consideration when designing new systems. Altogether, these aspects pose considerable challenges for successfully applying molecular photoswitches in aqueous systems, and in particular in biologically relevant media. In this review, we focus on fully water-soluble photoswitches, such as those used in biological environments, in both in vitro and in vivo studies. We discuss the design principles and prospects for water-soluble photoswitches to inspire and enable their future applications., Molecular photoswitches are inherently lipophilic and do not spontaneously dissolve in water. We describe the effect of water on the photochemical properties and strategies to solubilize organic photoswitches and apply them in aqueous media.

The adoption of Unmanned Aerial Vehicles (UAVs) in numerous sectors is projected to grow exponentially in the future as technology advances and regulation evolves. One of the promising applications of UAVs is in transportation systems. As the current transportation system is moving towards Intelligent Transportation Systems (ITS), UAVs will play a significant role in the functioning of ITS. This paper presents a survey on the recent advances of UAVs and their roles in current and future transportation systems. Moreover, the emerging technologies of UAVs in the transportation section and the current research areas are summarized. From the discussion, the challenges and opportunities of integrating UAVs towards future ITS are highlighted. In addition, some of the potential research areas involving UAVs in future ITS are also identified. This study aims to lay a foundation for the development of future intelligent and resilient transportation systems.

Moringa oleifera Lam. is an important plant with multiple benefits for humans, and has been termed “the miracle plant” by many. This study presents a bibliometric analysis of M. oleifera (MO) in the last two decades with data indexed on the Scopus database. The objective is to evaluate how research outputs on the plant have evolved within the period with a focus on country, institution, journal and author participation. The analysis was limited to the search command - article title “Moringa oleifera”, for original research articles and conference presentations. The search output was 2,345 documents, representing 97% of all time published reports on the subject. A data analysis software – VOSviewer 1.6.15 (Leiden, Netherlands) was used to analyze the data generated from Scopus. So far, 98 countries have contributed to research publications on MO, with India leading the pack. The most productive author is Rosângela Bergamasco of the Universidade Estadual de Maringa in Brazil with 60 published articles on MO. This institution is also the leading contributor to research outputs on the plant. The most cited author – Farooq Anwar is affiliated with the University of Sargodha, Pakistan with 1091 citations distributed over 11 publications on the plant. The South African Journal of Botany continues to lead in terms of the publication number with 64 original articles on MO while the Journal of Ethnopharmacology's published articles had the most citations (1166). VOSviewer analysis established Egypt, Nigeria and India as the countries with the best international link strength. The research areas on the plant are mainly on the pharmacological, food and nutritional uses as well as its applications in water treatment, environmental management and biofuel production.

The influence of family on expatriates and their families' international assignments experience have been long discussed in various disciplines. We undertake a systematic review of 151 articles on expatriates' families published between 2006 and 2020 in peer-reviewed academic journals in Business and Management, Medicine, Psychology, and Decision Sciences. Adopting a step-wise approach to conduct the review and using Leximancer, we analyze the literature and categorize it into five major themes: family's influence on expatriates; expatriation's influence on expatriate families; family and individual adjustment in the expatriation process; organizational practices concerning family issues in expatriation; and expatriate families' social interaction. This mapping, thematizing and systematic organizing of the literature allows us to identify research areas that have been overpopulated and others that have not received sufficient scholarly attention. By doing so, this study contributes to the literature by providing a multidisciplinary perspective on the issue of expatriates' families. We also present a research agenda to advance knowledge in the field and make recommendations for practice.

Nanopartículas de ferro são muito utilizadas em diversas áreas de pesquisa. O elemento químico ferro (Fe), sendo o quarto elemento mais abundante na crosta terrestre, e a substância mineral magnetita, com propriedade magnética, apresentam aplicações nas áreas industrial, ambiental, biomédica e de novas tecnologias. Este trabalho apresenta processo de síntese de nanopartículas partindo-se de sais precursores, bem como a caracterização dos produtos e as rotas para estabilizá-los. Os sais químicos precursores utilizados foram o cloreto férrico (FeCl3) e o sulfato ferroso (FeSO4) na proporção de 2:1, sob agitação por ultrassom e pH ácido. Para formação do precipitado de nanopartículas usou-se solução aquosa de hidróxido de sódio (NaOH) de pH 12. A difratometria de raio-X, mostra a presença de magnetita (Fe3O4) indicada pelos picos característicos de difração em graus 2Ө = 18° (largo), 31° (fino), 36° (bem definido), 43,4°, 45°, 53,6°, 57,7°, 63,3°. A microscopia eletrônica de transmissão mostra a morfologia dos produtos da síntese. Fatores que influenciam a estabilidade das partículas são agitação, o ajuste de pH, condições de secagem. O tamanho médio das nanopartículas de magnetitas é de aproximadamente 15 nm. Iron nanoparticles are widely used in several research areas. The chemical element iron (Fe), being the fourth most abundant element in the earth's crust, and the mineral substance magnetite, with magnetic properties, have applications in industrial, environmental, biomedical, and new technology areas. This work presents the process of synthesis of nanoparticles starting from precursor salts, as well as the characterization of the products and the routes to stabilize them. The precursor chemical salts were ferric chloride (FeCl3) and ferrous sulfate (FeSO4) in a 2:1 ratio, under ultrasound agitation and acidic pH. For the nanoparticles growth was applied aqueous solution of sodium hydroxide (NaOH) at pH 12. X-ray diffraction shows the presence of magnetite (Fe3O4) indicated by characteristic diffraction peaks in degrees 2Ө = 18° (wide), 31° (fine), 36° (well defined), 43.4°, 45°, 53.6°, 57.7°, 63.3°. Scanning electron microscopy shows the morphology of the synthesis products. Factors that influence the stability of the particles are agitation, the pH adjustment, and the conditions of drying. The average size of the magnetite nanoparticles is approximately 15 nm.

Journal of Food and Health (JOFH) is an open access journal in the field of foods, diets, probiotics, health and fitness. JOFH offer an important media or forum for researchers and academes to exchange the latest results from such research areas. JOFH provides quality service, including the submission process and the rapid double blind peer review, and only published online. Receiving types of manuscripts which include, original manuscripts or original research, literature review, systematic review and or meta-analysis, case report, supplements, commentaries and reports on research methodology or study design, negative results. Relevant topics may or may not be accepted, subject to the Chief Editor’s decision. Authors are advised to carefully read the author guidelines, especially the details about the ethics in publishing and manuscript style. The Editorial Office reserves the right to change the type of submission of a manuscript, based on the reviewers’ comments and the Editor’s decision.

The growth of the retraction databases reveals the disturbing trend in science and also the rising trend of citations of retracted papers is a serious concern. The objective of the study is to investigate the patterns of retractions through the team size and retracted citations. The publication records of 12,231 retracted papers indexed by Web of Science (WoS) are analyzed to investigate (i) the patterns of retraction associated with collaboration and team size; and (ii) the impact of retracted papers on the papers that are citing the retracted papers (retracted citations). The study demonstrates the collaboration patterns of retracted publications where 61.5% of authors have only one and 24.6% have two retracted papers; however, 2% of authors have more than retracted papers. Also, the temporal evolution of the team size reveals that teams smaller in size have more retractions. The impact of citing retracted papers reveals that 55.2% of retracted papers have been cited at least once. 1/4th of the citations to the retracted papers are self-citations which themselves are retractions. On average 71.4% citations are the non-retracted citations and 28.6% citations are retracted citations which are mostly the self-citations. Last, the variation in average team size and average retracted citations in various research areas (having high retraction) is presented. Retracted publications in high-impact journals are highly cited.

Lognormal models have broad applications in various research areas such as economics, actuarial science, biology, environmental science and psychology. In this article, we summarize all the existin...

Introducción: Evaluar la personalidad es cada vez más necesario dentro de diferentes áreas de investigación. A pesar de que existen varias opciones para la evaluación del modelo de los cinco factores; existen pocos estudios que reporten las características en población Latinoamericana. Objetivo: El presente estudio presenta un análisis de las propiedades psicométricas del inventario de los cinco factores de personalidad (BFI, por sus siglas en ingles) que evalúa la personalidad siguiendo del modelo de los cinco grandes. Resultados: Los resultados muestran una adecuada fiabilidad (α = .78) de la prueba. La evaluación de la validez exploratoria y confirmatoria sugiere la que el instrumento se puede usar en población mexicana, pero surge la necesidad de revisar algunos ítems que son culturalmente equivalentes, así como el factor Agradabilidad y las asociaciones entre factores que pudiera obedecer a factores culturales. Discusión: La incorporación de metodologías robustas que consideran la naturaleza ordinal de las escalas Likert, como el análisis factorial con la incorporación del intercepto aleatorio; permiten mejorar el ajuste de los modelos sin alterar la estructura de las covarianzas ni usar los estimadores para ajustar las covarianzas. Es necesaria mayor investigación en población mexicana.

This study explores the affordances that the open-ended questions hold in comparison with those of closed-ended questions through examining 6th grade students’ performance on a mathematics test. For this purpose, a questionnaire including 2 open-ended and 2 closed-ended questions was applied to 36 6th grade students. The questions were prepared in the light of four categories: (i) question with one correct outcome (closed-ended), (ii) question with multiple fixed outcomes (closed-ended), (iii) question with multiple variable outcomes (open-ended), and (iv) question with limitless outcomes (open-ended). The collected data were analysed in terms of correct, incorrect, uncategorized and unanswered categories as well as with regard to the diversity of the responses. The findings reveal that students showed lower performances for the question that requires limitless outcomes, there were a lack of generalizations or general rules in their responses and they provided more diverse responses for the open-ended questions. The findings were discussed with regard to higher-order thinking skills such as creativity and divergent thinking as they are often associated with open-ended questions and their affordances. Finally some implications are put forward and further research areas are highlighted.

Purpose This study aims to contribute to literature on mobile learning (m-learning) by proposing four research clusters whereby scholars can expand m-learning research to facilitate effective learning experiences for students. Design/methodology/approach This study reviews student-centric literature on m-learning since 2010 and presents insights on m-learning while applying well-established bibliometric techniques. Consequently, 722 articles published in the past decade were evaluated by identifying key research areas, most influential authors, countries, journals and organisations. Most influential studies based on number of citations were also examined. Findings Through article co-citation analysis, four clusters representing m-learning literature were identified: concept of m-learning, application of m-learning in education, designing framework for model learning/acceptance and emerging technologies. Originality/value As mobile learning (m-learning) has undergone an evolution from being an emerging field to a significant teaching and research tool, it is pertinent to explore and identify the trends of m-learning research.

Structural optimization within concrete construction has been increasingly taken up in research within the last two decades. Possible drivers are the need for material-reduced and thus resource-efficient structures as well as recent advancements in automated concrete construction. However, structural concrete is characterized by nonlinear material behavior. Consequently, the merge of structural concrete design and topology optimization is not trivial. This paper reviews and assesses the topic of topology optimization within concrete construction, carrying out an extensive quantitative as well as qualitative review on practical and numerical applications. The following research areas are identified: Multimaterial modeling, stress constraints, concrete damage modeling, strut and tie modeling, combined truss-continuum topology optimization, the consideration of multiple load cases, a focus on construction techniques and alternative approaches. Although the number of research papers dealing with the topic of topology optimization in concrete construction is numerous, there are only few that actually realized topology optimized concrete structures. In addition, only a little number of experiments was performed for an objective evaluation of the found geometries so far. Concluding this review, a list of future challenges, like the incorporation of sustainability measurements within the optimization process, is given and thus serves as a guidance for subsequent research.

Scientific exploration of zoo animals is one of the main missions of modern zoos. As scientific achievements are best reflected within scientific literature, we screened appropriate literature search outcomes from the 5 highest ranked zoos in the D-A-CH region (Germany-Austria-Switzerland) in order to deduce suggestions for optimizations of future research strategies.Literature search was done by entering "Zoo Vienna", "Tiergarten Schönbrunn", "Zoo Berlin", "Tiergarten Berlin", "Tierpark Hellabrunn", "Tierpark Hagenbeck", and "Zoo Zurich" on PubMed and Scopus for the period 2000-2020. These 5 European zoos were chosen due to their broad public recognition and international importance. Inclusion criterion for the literature list was the description/mentioning of analysed animals or samples with a clear affiliation to the respective zoo in the materials and methods or acknowledgements sections. Search hits were then allocated to the following 7 areas: animal nutrition, biology, ethology, infectiology, reproduction, phylogenetics, and clinical medicine. Also, portions of higher animal taxa (and species, if appropriate) were recorded.A total of 142 papers has been published. Mammals, especially large ones, were clearly over-represented in literature with 2 thirds of analysed papers dealing with them. Sauropsids (birds and reptiles) were treated in 28 % and non-amniotic vertebrates (amphibians and fish) as well as invertebrates in only 3 % each. This apportionment is in no relation to the species numbers of the respective higher animal taxa. The predominating research areas (covered by approximately 75 % of papers) were ethological studies, followed by papers on infectious diseases, and finally papers on biology with morphological, physiological, and molecular biological themes. Research on reproductive biology/medicine, which is considered to be of tremendous importance for the establishment of ex-situ populations and thus for the conservation of endangered species, has been covered by only 6 % of papers. Future research should more intensely keep an eye on that discipline, especially in non-mammalian vertebrates.Die wissenschaftliche Untersuchung von Zootieren ist eine der Hauptaufgaben moderner, wissenschaftlich geführter Tiergärten. Da sich wissenschaftlicher Fortschritt am ehesten in der wissenschaftlichen Literatur widerspiegelt, führten wir eine entsprechende kritische Literaturrecherche durch, um in weiterer Folge Optimierungsvorschläge für zukünftige Forschungsstrategien am Gebiet der Zooveterinärmedizin zu erarbeiten.Für die Literatursuche wurden die Begriffe ”Zoo Vienna”, ”Tiergarten Schönbrunn”, ”Zoo Berlin”, ”Tiergarten Berlin”, “Tierpark Hellabrunn“, “Tierpark Hagenbeck“ und ”Zoo Zurich” in den Datenbanken PubMed und Scopus für den Zeitraum 2000–2020 eingegeben. Diese fünf europäischen Zoos wurden aufgrund ihrer großen internationalen Bedeutung und ihres hohen Bekanntheitsgrades ausgewählt. Einschlusskriterium für die Literaturliste war die Beschreibung oder Nennung der untersuchten Tiere bzw. Proben mit eindeutiger Zugehörigkeit zum gesuchten Zoo in den Abschnitten zu Material und Methode oder in der Danksagung. In der folgenden deskriptiv-statistischen Auswertung der Arbeiten wurde untersucht, wie die höheren Tiertaxa und die behandelten Fachgebiete (Tierernährung, Biologie, Ethologie, Infektiologie, Reproduktionsbiologie/-medizin, Phylogenetik, klinische Medizin) prozentuell in den Publikationen abgebildet waren.Die Suche ergab insgesamt 142 Publikationen. Bezogen auf die behandelten Taxa waren die Säugetiere – und hier v. a. Großsäuger – mit 2 Drittel der Arbeiten überrepräsentiert. Sauropsiden (Reptilien und Vögel) wurden in 28 % und nichtamniotische Vertebraten (Amphibien und Fische) sowie Wirbellose in jeweils nur 3 % der Arbeiten behandelt. Diese Verteilung steht in keiner Relation zur Anzahl der Arten in den jeweiligen höheren Taxa. Die meistuntersuchten Thematiken ließen sich mit 75 % der Arbeiten den Disziplinen der Ethologie, der Infektiologie und verschiedenen zoologischen Disziplinen aus Anatomie, Physiologie und Molekulargenetik (zusammengefasst im Fachgebiet Biologie) zuordnen. Arbeiten auf dem Gebiet der Reproduktionsbiologie und Reproduktionsmedizin waren mit 6 % deutlich unterrepräsentiert und dies, obwohl gerade diese Fachdisziplinen für die Schaffung von Ex-situ-Populationen und damit für Arterhaltungsprogramme von größter Wichtigkeit sind. Zukünftige Forschungsstrategien auf dem Gebiet der Zootiermedizin sollten somit letzteren Gebieten eine größere Bedeutung beimessen.

Environment protection and food safety are two critical issues in the world. In this review, a novel approach which integrates statistical study and subjective discussion was adopted to review recent advances on environment and food safety. Firstly, a scientometric-based statistical study was conducted based on 4904 publications collected from the Web of Science Core Collection database. It was found that the research on environment and food safety was growing steadily from 2001 to 2020. Interestingly, the statistical analysis of most-cited papers, titles, abstracts, keywords, and research areas revealed that the research on environment and food safety was diverse and multidisciplinary. In addition to the scientometric study, strategies to protect environment and ensure food safety were critically discussed, followed by a discussion on the emerging research topics, including emerging contaminates (e.g., microplastics), rapid detection of contaminants (e.g., biosensors), and environment friendly food packaging materials (e.g., biodegradable polymers). Finally, current challenges and future research directions were proposed. Supplementary Information The online version contains supplementary material available at 10.1007/s11356-021-16069-6.

Background Drug-induced liver injury (DILI) has become one of the most common and serious adverse drug reactions owing to its high morbidity and leading cause of hepatic failures, which had attracted great attentions worldwide in the past two decades. A need therefore exists to conduct a bibliometric and visualized analysis of the global research trends on DILI with the aim of identifying the status of current research and prioritize the future research areas. Methods Publications related to DILI from 1999 to 2019 were extracted through an electronic search of the Web of Science (WoS) and PubMed databases. VOSviewer software was used to perform visualized analysis of bibliographic coupling, co-authorship, co-citation and co-occurrence, and to assess the global trends. Results Totally of 6,563 publications were identified based on the inclusion criteria. It is noted that the global trends of literatures on DILI showed a significant increase over time and more importantly predict the relevant publications will rise continuously in the coming decades. The United States led in terms of publication numbers with the most citations (the highest h-index). Hepatology made great contributions to the highest h-index and the most citations of publications. University of North Carolina was regarded as the most contributive institution. Notably, after conducting co-occurrence and cluster analysis of keywords and citation networks, it is shown that the pathogenesis, clinical manifestations, diagnosis and risk factors of this field will become the most prominent research hotspots. Conclusions The mapping results provides global development trends of publications on DILI from 1999 to 2019. Future studies focused on the diagnosis and predisposing factors of this field will be encouraged.

This review deals with the historical development of all N-F fluorinating agents developed so far. The unique properties of fluorine make fluorinated organic compounds attractive in many research areas and therefore fluorinating agents are important. N-F agents have proven useful by virtue of their easy handling. This reagent class includes many types of N-F compounds: perfluoro-N-fluoropiperidine, N-fluoro-2-pyridone, N-fluoro-N-alkylarenesulfonamides, N-fluoropyridinium salts and derivatives, N-fluoroquinuclidium salts, N-fluoro-trifluoromethanesulfonimide, N-fluoro-sultams, N-fluoro-benzothiazole dioxides, N-fluoro-lactams, N-fluoro-o-benzenedisulfonimide, N-fluoro-benzenesulfonimide, 1-alkyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane salts, N-fluoropyridinium-2-sulfonate derivatives, 1-fluoro-4-hydroxy-1,4-diazoniabicyclo[2.2.2]octane salts, N-fluorodinitroimidazole, N-fluoro-trichloro-1,3,5-triazinium salt, N-F ethano-Tröger’s base derivatives, N-fluoro-methanesulfonimide, N-fluoro-N-arylarenesulfonamides, bisN-F salts such as N,N’-difluorobipyridinium salts and N,N’-difluoro-1,4-diazoniabicyclo[2.2.2]octane salts, and their many derivatives and analogs, including chiral N-F reagents such as optically active N-fluoro-sultam derivatives, N-fluoro-alkaloid derivatives, DABCO-based N-F derivatives, and N-F binaphthyldisulfonimides. The synthesis and reactions of these reagents are described chronologically and the review also discusses the relative fluorination power of each reagent and their mechanisms chronicling developments from a historical perspective.

Hand pose estimation is one of the most attractive research areas for image processing. Among the human body parts, hands are particularly important for human–machine interactions. The advent of commercial depth cameras along with the rapid growth of deep learning has made great progress in all image processing fields, especially in hand pose estimation. In this study, using depth data, we introduce two hybrid deep neural networks to estimate 3D hand poses with fewer computations and higher accuracy compared with their counterparts. Due to the fact that the dimensions of data are reduced while passing through successive layers of networks, which causes data to be lost, we use the concept of residual network to compensate this phenomenon. By incorporating data from several views, the estimated poses are more robust in the occlusions. Evaluation results show the superiority of the proposed networks in terms of accuracy and implementation complexity.

Objective: Immediately after the outbreak of nCoV, many clinical trials are registered for COVID-19. The numbers of registrations are now raising inordinately. It is challenging to understand which research areas are explored in this massive pool of clinical studies. If such information can be compiled, then it is easy to explore new research studies for possible contributions in COVID-19 research. Methods: In the present work, a text-mining technique of artificial intelligence is utilized to map the research domains explored through the clinical trials of COVID-19. With the help of the open-- source and graphical user interface-based tool, 3007 clinical trials are analyzed here. The dataset is acquired from the international clinical trial registry platform of WHO. With the help of hierarchical cluster analysis, the clinical trials were grouped according to their common research studies. These clusters are analyzed manually using their word clouds for understanding the scientific area of a particular cluster. The scientific fields of clinical studies are comprehensively reviewed and discussed based on this analysis. Results: More than three-thousand clinical trials are grouped in 212 clusters by hierarchical cluster analysis. Manual intervention of these clusters using their individual word-cloud helped to identify various scientific areas which are explored in COVID19 related clinical studies. Conclusion: The text-mining is an easy and fastest way to explore many registered clinical trials. In our study, thirteen major clusters or research areas were identified in which the majority of clinical trials were registered. Many other uncategorized clinical studies were also identified as “miscellaneous studies”. The clinical trials within the individual cluster were studied, and their research purposes are compiled comprehensively in the present work.

The application of artificial intelligence (AI) to chemistry has grown tremendously in recent years. In this Review, we studied the growth and distribution of AI-related chemistry publications in the last two decades using the CAS Content Collection. The volume of both journal and patent publications have increased dramatically, especially since 2015. Study of the distribution of publications over various chemistry research areas revealed that analytical chemistry and biochemistry are integrating AI to the greatest extent and with the highest growth rates. We also investigated trends in interdisciplinary research and identified frequently occurring combinations of research areas in publications. Furthermore, topic analyses were conducted for journal and patent publications to illustrate emerging associations of AI with certain chemistry research topics. Notable publications in various chemistry disciplines were then evaluated and presented to highlight emerging use cases. Finally, the occurrence of different classes of substances and their roles in AI-related chemistry research were quantified, further detailing the popularity of AI adoption in the life sciences and analytical chemistry. In summary, this Review offers a broad overview of how AI has progressed in various fields of chemistry and aims to provide an understanding of its future directions.

For a variety of reasons, emerging research areas can excite and often motivate people to explore and even contribute. But too often even for experienced scholars, academic prowess, good intentions...

Deep neural networks (DNN) have achieved great success in several research areas like information retrieval, image processing, and speech recognition. In the field of machine translation, neural machine translation (NMT) has been able to overcome the statistical machine translation (SMT), which has been the dominant technology for a long-term span of time. The recent machine translation approach, which consists of two sub networks named an encoder and a decoder, has gained state-of-the-art performance on different benchmarks and for several language pairs. The increasing interest of researchers in NMT is due to its simplicity compared to SMT which consists of several components tuned separately. This paper describes the evolution of NMT. The different attention mechanism architectures are discussed and the purpose of each. The paper also presents some toolkits that are developed specifically for research and production of NMT systems. The superiority of NMT over SMT is discussed, as well as the problems facing NMT.

Packaging materials research areas have a great concerned to develop and create attractive packaging item with eco-friendly and health impact. There is still an urgent need to establish innovative design and production standards that attract the eyes of the consumer, and these standards must be cost-effective and for the production. So this study aims to ergonomic science applied to design comfortable packaging bottle with easy drinkable and handling easily and using future environmentally friendly materials in the world of packaging. 3D printing technology was used to produce three bottle designs with a 45ᵒ inclination angle produced from polylactic acid (PLA) filament as biodegradable and eco-friendly polymer. The 3D printed bottles are designed as a prototype for the consumer. Three PLA bottles were investigated as acceptable packaging materials with mechanical properties, overall migration and migrated toxic heavy metals detection. The samples were analyzed for heavy metal content per ASTM E1613-04 where overall migration was measured according to EC 2011/10. Tensile strength and elongation at break exhibited good physico-mechanical properties with for 43 MPa and4.6 %, respectively as hard packaging item. The overall migration was acceptable according to EC 2011/10. In addition, migrated heavy metals detection shown tiny value as ≥ 0.3 ppm. Designing bottles were digitally printed to add a logo on bottle beside printed paper sticker. Moreover, statistical questionnaire scanning was shown a great acceptable percentage with more than 83% for designing, printing and easy use of produced bottles. 3D printing, ergonomic design and packaging materials research fields are combined to create sustainable packaging bottle for easy and health use.

This paper presents a current research trend based on the best papers awarded in 2019 and 2020 by Materials Transactions. The summary includes the 8 papers carefully selected from the articles in the research areas of materials physics, microstructures of materials, mechanics of materials, materials chemistry, materials processing, and engineering materials and their applications. Four out of the 8 best papers are those specially selected for young scientists who are the age of 35 or younger. Here, brief summary is given for the introduction of high quality papers published in Materials Transactions.

El objetivo del estudio que se muestra a continuación se dirigió a analizar los currículos de la especialidad de matemática, de facultades de educación, correspondiente a cinco universidades peruanas. Para ello se establecieron las diferencias y similitudes que hay en dichos currículos, respondiendo a las siguientes interrogantes: ¿son pertinentes los currículos de formación profesional a las demandas reales de las instituciones educativas?, ¿cómo operacionalizan el enfoque de competencias en dichos currículos?, ¿los currículos responden a los perfiles del egresado? Para ello se estudiaron los componentes curriculares: propósitos, contenidos, metodología y evaluación; bajo el enfoque mixto, y científico adecuado, utilizando como métodos específicos: el descriptivo y el análisis discursivo; los que arrojaron entre otros, los resultados siguientes: a) El trabajo por competencias se asume de forma procedimental, lo que trae como consecuencia, diferentes formas de aplicarlo. b) La dosificación de créditos de las áreas disciplinares, didácticas e investigación, difieren significativamente.

This study aims to evaluate the current status and perspectives on the use of Japanese long-term care (LTC) claims databases for research. We conducted a comprehensive literature search of PubMed and the Japan Medical Abstracts Society (Ichushi-Web), focusing on LTC claims data analyses published between 2000 and 2020. We summarized the study characteristics, database characteristics, and the research areas related to health services that were studied. In total, 86 journal articles (12 in Japanese and 74 in English) were included in our review. A particularly remarkable increase in the number of publications from 2016 to 2020 was observed. We extracted more publications with combined databases (n = 64) than those that only used a single source of the LTC claims databases (n = 22). More than half of the studies analyzed healthcare expenditure, healthcare utilization, and quality of care which were relevant to health services research. The most frequently mentioned limitation was the lack of validation in variables stored in the LTC claims databases. In conclusion, the LTC claims databases could serve as important sources of information for the evaluation of healthcare delivery, quality of care, and LTC policy.

Present study was conducted in three different Upazilas viz., Batiaghata, Dacope and Rupsha of Khulna district, Bangladesh from August 2016 to May 2017. Data were collected through personal contact, farms and market survey and discussion with shrimp farmers and drug sellers. Farmers of the research areas used Oxolinic acid, Renamucin, Oxytetracucline, Lime, Salt, Formalin, Eco-solution, Basudin and Timsen to treat the viral, bacterial and fungal diseases. Average recovery of 55-60% and 35-40% were recorded from bacterial and fungal diseases of shrimp respectively, but there was no recovery in case of viral diseases. Shrimps of nontreated ghers were affected by WSSV, Black gill disease, Black spot disease, Zoothumnium and external fouling but almost no disease were observed in aqua drugs-treated ponds. Histological findings showed that shrimp muscles and hepatopancreas in drug treated ponds and ghers had some pathological changes like necrosis, vacuums and hemorrhages which were severe in winter season, whereas, normal structure of muscle and hepatopancreas were observed during summer season. Production of shrimp in the study areas was recorded 6916 Kg/ha in probiotics and aqua-drugs treated ponds, whereas, 543 Kg/ha in non-treated ghers. From the present study it could be concluded that aqua-drugs and chemicals have positive effect on shrimp health and production except some pathological changes in the investigated organgs of shrimp especially during winter season.

This study explores the publishing patterns of a specialized accounting history journal - De Computis,Revista Espanola de Historia de la Contabilidad. The survey is confined to 172 refereed contributions publishedin 16 years between 2004 and 2019. This article depicts dominant research trends and the decline in research areasby examining authorship patterns, topics, periods, sources, and language. One of our principal findings revealsthat the historical research landscape in De Computis is transforming since its inception to Emerging SourcesCitation Index in 2015. There is an escalation in non-Spanish articles' percentage and a decline in archival sources'usage. The 18th and 19th centuries stand out as the most popular research periods. We conclude with somesuggestions for the journal moving forward.

In this study, altmetrics for LIS research papers, and whether OA affects the altmetrics, were analyzed. In addition, by analyzing the differences in the altmetrics in 10 major research areas of LIS, this study identified sub-research topics that are frequently read outside of academia or mentioned on social media. This study sampled a thousand papers highly cited in the WOS, OA status and altmetrics of papers were collected through Unpaywall and PlumX. The collected data was analyzed as follows. Whether the OA affects the usage, capture, mention, and social media attention of the altmetrics was identified through a Mann–Whitney analysis, and was presented visually through a correspondence analysis. And then using factor analysis and correlation analysis, this study understand whether the article cited in an academic paper or bookmarked for reading showed a sensitive reaction to social media as well. Finally to understand the difference in altmetrics sensitivity of 10 LIS sub-subject topics, papers showing a high sensitivity for each of the 6 sources were selected, and a correspondence analysis was conducted on the relationship with the subject topics. The analysis results can be summarized as follows: First, 63% of the papers to be analyzed had a Mendeley bookmark reader, whereas 36%, 17%, 3%, and 4% had views, tweets, blogs, and Wiki references, respectively. Second, views, blogs, and tweets showed greater sensitivity in open-access papers, and the number of Mendeley bookmark readers was the only source of altmetrics that had a significant correlation with citations. Fourth, information technology and knowledge management topics showed a high number of citations and readers, and public libraries and websites appeared as research topics with a significant usage. In addition, academic communication appeared as a topic with high sensitivity to tweets.

espanolTomando en cuenta el estatus concedido al embrion humano al interior de los estudios contemporaneos de la antropologia del parentesco, el presente articulo aborda tres areas fundamentales de indagacion. En primer lugar, se analizan las repre-sentaciones que el mundo actual esboza en lo relativo a la figura del embrion a partir de la observacion de la relacion que estas representaciones guardan con la idea de individuo construida por las sociedades neoliberales. En segundo lugar, se observa la manera en que la vida embrionaria y fetal se esboza para reconsiderar las oposiciones clasicas realizadas por la antropologia entre sociedades relacionales y sociedades conformadas por individuos. En tercer lugar, se evidencia la relevan-cia que posee la dimension cosmologica y trascendental para comprender de un modo no naturalizado la existencia social de la persona humana, relativizando de esta manera la distincion entre sociedades relacionales y sociedades de individuos. EnglishConsidering the status given to the human embryo within the sexual reproduction techniques, and the contemporary studies on the anthropology of parentage, this article addresses three fundamental research areas. First, it analyzes the constructs and representations that the contemporary world outlines regarding the human embryo figure, particularly highli-ghting the relationship between these representations and the idea of the individual, constructed by neoliberal societies. Second, it aims to observe the ways offered by the embryonic and fetal lives to reconsider the oppositions established by anthropology in a disciplinary manner, to make a distinction between relational societies and societies structured by indivi-duals. Third, it shows the importance of the cosmological and transcendent dimension to understand, in a non-naturalized manner, the acquisition of societal ways of existence of the individuals.

The mechanism of flow instability, which involves complex gas–liquid interactions and multiscale vortical structures, is one of the hot research areas in cavitating flow. The role of turbulence modeling is crucial in the numerical investigation of unsteady flow characteristics. Although large-eddy simulation (LES) has been used as a reliable numerical method, it is computationally costly. In this work, we used a hybrid Reynolds-averaged Navier–Stokes (RANS) and LES model, that is, stress-blended eddy simulation (SBES), to improve the prediction capability for the cloud cavitating flow. Our hybrid approach introduces a shielding function to integrate the RANS model with the LES applied only regionally, such as to large-scale separated flow regions. The results showed that the periodic shedding of cavity growth, break off, and collapse around a three-dimensional Clark-Y hydrofoil was reproduced in accordance with experimental observations. The lift/drag coefficients, streamwise velocity profiles, and cavity patterns obtained by the SBES model were in better agreement with the experimental data than those obtained by the modified RANS model. The re-entrant jet dynamics responsible for the break off of the attached cavity were discussed. Further analysis of vorticity transportation indicated that the stretching and dilatation terms dominated the development of vorticity around the hydrofoil. In conclusion, the SBES model can be used to predict cavitating turbulent flows in practical engineering applications.

Na ultima decada houve notavel aumento no numero de estudos buscando incorporar as caracteristicas funcionais das especies na quantificacao da diversidade das comunidades ( i.e. , diversidade funcional). A abordagem funcional vem contribuindo para avancos na ecologia teorica e aplicada. Estudos desenvolvidos no Brasil representam uma porcao significativa da producao cientifica mundial sobre diversidade funcional de peixes de riachos. Entretanto, ha um claro vies, com a maior parte dos estudos avaliando a resposta das comunidades aos gradientes ambientais naturais e antropicos. Outras linhas de investigacao, como conservacao e o efeito da biodiversidade sobre o funcionamento dos ecossistemas, ainda sao escassas. Destacamos aqui as bases conceituais e metodologicas da abordagem funcional na ictiologia. Discutimos questoes chave, como a selecao dos atributos funcionais em peixes de riacho, as principais facetas da diversidade funcional e os indices que podem ser utilizados para calcula-las, nocoes gerais sobre composicao funcional, diversidade beta funcional e modelos nulos. Tambem abordamos o estado da arte dos estudos de diversidade funcional no Brasil e levantamos as principais lacunas e perspectivas para o avanco no conhecimento da ecologia funcional com peixes de riacho. FUNCTIONAL DIVERSITY OF STREAM FISH: In the last decade there was a remarkable increase in the number of studies incorporating species functional traits to quantify the diversity of communities ( i.e. , functional diversity). The functional approach has contributed to advances in theoretical and applied ecology. Studies developed in Brazil represent a significant portion of the world's scientific production on stream fish functional diversity. However, there is a clear bias, with most studies assessing communities' response to natural and anthropogenic environmental gradients. Other research areas such as conservation and the effect of biodiversity on ecosystem functioning are still scarce. Here we highlight the conceptual and methodological bases of the functional approach in ichthyology. We discuss key questions such as functional trait selection for stream fish, the main facets of functional diversity and indices to calculate them, general notions on functional composition, functional beta diversity and null models. We also address the state of the art of functional diversity studies in Brazil and raised the main gaps and perspectives for advancing the knowledge of stream fish functional ecology.

Anthropogenic warming is expected to accelerate global soil organic carbon (SOC) losses via microbial decomposition, yet, there is still no consensus on the loss magnitude. In this Perspective, we argue that, despite the mechanistic uncertainty underlying these losses, there is confidence that a strong, positive land carbon-climate feedback can be expected. Two major lines of evidence support net global SOC losses with warming via increases in soil microbial metabolic activity: the increase in soil respiration with temperature and the accumulation of SOC in low mean annual temperature regions. Warming-induced SOC losses are likely to be of a magnitude relevant for emission negotiations and necessitate more aggressive emission reduction targets to limit climate change to 1.5 degrees C by 2100. We suggest that microbial community-temperature interactions, and how they are influenced by substrate availability, are promising research areas to improve the accuracy and precision of the magnitude estimates of projected SOC losses. Degradation of soil organic carbon is expected to accelerate with increasing global temperatures, but the magnitude of change is controversial. This Perspective discusses evidence supporting a large loss of soil organic carbon and its broader significance.