1,720,965 research outputs found
Fattening flame retardants: does BDE-47 increase the risk of childhood obesity?
No full textChildhood obesity has increased globally by 31% in the last decade. This is thought to be due to a variety of pre-and postnatal factors, with a novel focus on endocrine disrupting chemicals known as "obesogens" and their effects on development during critical periods. Obesogens are known to alter transcription factors, enzymes and adipokines involved in adipose tissue (AT) formation. More specifically flame-retardants like BDE-47 are thought to have effects on adipogenesis during development. This was analyzed through in-vitro studies on human derived mesenchymal stem cells (MSCs) and murine derived 3T3-L1 pre-adipocytes, exposed to varying concentrations of BDE-47. This study also incorporated analysis of the German LINA (Lifestyle and Environmental factors and their influence on Newborns Allergy Risk) cohort study, to determine how changing furniture, with potential flame retardants during early childhood could affect the child's weight development. From the in-vitro studies, there was a significant increase in triglyceride storage in both 3T3-L1 and MSCs exposed to 10-11M(0.01nM) of BDE-47. For the 3T3-L1's, there was an increase in triglyceride storage at cells exposed to 10-8, 10-6 M of BDE-47, revealing a U-shaped curve. Analysis of the adipocyte specific genes showed inconsistent results and needs further investigation. However, there was also a significant increase in global DNA methylation for 3T3-L1's exposed to 10-11M (0.01 nM) of BDE-47, but not higher concentrations, which provides a potential epigenetic mechanism for BDE-47 action. The LINA analysis revealed significant associations between the purchase of new furniture when the child was three with the child's BMI z-score in later years. Therefore, BDE-47 has the ability to affect DNA at extremely low concentrations, which is possibly related to the increased triglyceride storage. This highlights the importance of investigating various modes of action for endocrine disrupting chemicals and their potential harm to human health.</p
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Perinatal risk factors for childhood overweight development
Full text linkTrotz des Wissens, dass der Lebensstil des 20ten Jahrhunderts mit der damit einhergehenden hoch-kalorischen Ernährung und reduzierten Bewegung zum Anstieg der Prävalenz für Übergewicht beigetragen hat, kann dies allein nicht die weltweit drastisch steigende Prävalenz von Übergewicht erklären. Stattdessen sind in den letzten Jahren verschiedene Umwelteinflüsse und die frühe embryonale Prägung in den Fokus der Wissenschaft gerückt, um die Wurzeln dieser Epidemie zu ergründen. Diese Arbeit zeigt, dass das Risiko für kindliches Übergewicht durch Faktoren wie einem veränderten mütterlichen Immunstatus und die pränatale Exposition mit endokrinen Disruptoren (z.B. Bisphenol A und Parabene) erhöht werden kann. Vermittelt wird dieses Risiko über eine erhöhte Adipozytendifferenzierung, veränderte Wahrnehmung von Hunger und Sättigung oder eine metabolische Fehlprägung während sensitiver Phasen in der Entwicklung. Demzufolge sollte eine Prävention von Übergewicht bereits bevor der Geburt starten.Despite the common knowledge that the 20th century lifestyle with a high caloric food intake and sedentary behaviour contribute to an increased prevalence for overweight and obesity, both cannot explain the fast increase in obesity rates all over the world. Hence, environmental, socio-economic and epigenetic factors gained more attention in the scientific community to unravel the roots of this epidemic. This work shows that early life adverse exposures especially during the sensitive perinatal period can prime children’s long-term weight development through various mechanisms. An altered maternal immune status during pregnancy may alter the children’s metabolism and endocrine disruptors like bisphenol A or parabens can alter adipocyte development through epigenetic mechanism or impact the signalling of hunger and satiety, thereby setting children on higher risk for overweight development. Based on the present data prevention of overweight should therefore start already before birth.vorgelegt von Beate Lepper
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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