1,721,017 research outputs found
Hair trace elementary profiles in aging rodents and primates: links to altered cell homeodynamics and disease
No full textAging is associated with an increased incidence of pathological conditions such as neurodegeneration, cardiovascular and renal disease, and cancer. These conditions are believed to be linked to a disruption in cell homeodynamics, which is regulated by essential trace elements. In this study we used hair elementary analysis by inductively coupled plasma mass spectrometry (ICPMS) to examine age-related profiles of 47 elements in both rats and common marmoset monkeys. Hair was collected from young adult (6 months) and aged (18 months) Long-Evans male rats, and young adult (2 years), middle-aged (4 years) and aged (> 8 years) marmosets. The results revealed that aging reduces content levels of cobalt, potassium and selenium while content levels of aluminium, arsenic, boron, mercury, molybdenum, and titanium were elevated in aged rats. Similarly, aged marmosets showed reduced levels of cobalt and elevated levels of aluminium. Case studies in aged rats revealed that myocardial infarction was associated with elevated levels of sodium, potassium and cadmium and reduced zinc, while renal failure was linked to elevated content of potassium, chloride and boron and reduced contents of manganese. Carcinoma was linked to elevated arsenic and reduced selenium levels. These findings indicate that hair elementary profiles in healthy aging and age-related diseases reflect altered cell and organ metabolic functions. Cobalt and aluminium in particular may serve as biomarkers of aging in animal models. Thus, elementary deposition in hair may have predictive and diagnostic value in age-related pathological conditions, including cardiovascular and kidney disease and cancer
Animal Models of Fetal Programming: Focus on Chronic Maternal Stress During Pregnancy and Neurodevelopment
No full textAnimal models of fetal programming contribute in three synergistic ways to understanding and treating human diseases or predispositions to diseases, which emerge from in utero insults leading to fetal programming. Firstly, animal models serve to confirm observationsderived in epidemiological studies. Secondly, animal models provide insights into mechanisms and render novel putative biomarkers of various effects of fetal programming that are relevant for early identification of affected individuals, children and adults. Thirdly, animal models permit testing of therapeutic interventions before they are translated into clinical intervention studies.Fil: Frasch, Martin Gerbert. University of Washington; Estados UnidosFil: Schulkin, Jay A.. University of Washington; Estados UnidosFil: Metz, Gerlinde A. S.. University of Lethbridge; CanadáFil: Antonelli, Marta Cristina. Universidad de Buenos Aires. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
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
Ancestral prenatal stress in F3 and F4 rats: the match/mismatch hypothesis
No full textAll procedures in this study were approved by the University of Lethbridge Animal Care Committee in compliance with the standards set out by the Canadian Council for Animal Care.
The authors gratefully acknowledge support with the experiments by Sophia Vathracoulis.Cumulative lifetime stress can have detrimental impacts on developmental trajectories and life outcomes. The impacts of stress over multiple generations become a more complex issue. This thesis aimed to understand the impacts of prenatal stress exposure over four generations of rats and worked to develop a maternal stress index (MSI) that adequately quantifies the physiological dysregulation induced by stress. This study assessed the impacts of two different protocols of ancestral prenatal stress in rats. The models included transgenerational prenatal stress (TPS) where the filial 0 generation (F0) dams experienced mild gestational stress, and each subsequent generation afterwards experienced unstressed pregnancies, and multigenerational prenatal stress (MPS), in which each generation experienced stress during gestation. The first study investigated the impacts on F2 dams and F3 young offspring and revealed that the novel MSI was sensitive to maternal stress and predicted the behavioural phenotype in the offspring. The TPS lineage was linked to more adverse pregnancy and developmental outcomes than the MPS lineage. The second study measured the impacts of TPS and MPS on the F4 generation. It was determined that some of the negative impacts found in the F3 generation had disappeared, but reduced exploration in MPS animals was observed. The third and final study focused on the aging F4 generation of the MPS lineage and found that anxiety behaviour at postnatal day 110 was able to predict anxiety at 12 months of age. It was also determined that the lifespan of MPS animals lengthened compared to controls. These studies reveal patterns of generational adaptation to stress and postulate models that predict lifetime health trajectories.This work was supported by CIHR Project Scheme #363195 (G.M.), NSERC Discovery Grant #05628 and NSERC Discovery Accelerator Supplement #00031 (G.M.
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
- …
