331 research outputs found

    On the origin of variable structures in the winds of hot luminous stars

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    Examination of the temporal variability properties of several strong optical recombination lines in a large sample of Galactic Wolf-Rayet (WR) stars reveals possible trends, especially in the more homogeneous WC than the diverse WN subtypes, of increasing wind variability with cooler subtypes. This could imply that a serious contender for the driver of the variations is stochastic, magnetic subsurface convection associated with the 170 kK partial-ionization zone of iron, which should occupy a deeper and larger zone of greater mass in cooler WR subtypes. This empirical evidence suggests that the heretofore proposed ubiquitous driver of wind variability, radiative instabilities, may not be the only mechanism playing a role in the stochastic multiple small-scaled structures seen in the winds of hot luminous stars. In addition to small-scale stochastic behaviour, subsurface convection guided by a global magnetic field with localized emerging loops may also be at the origin of the large-scale corotating interaction regions as seen frequently in O stars and occasionally in the winds of their descendant WR stars.Comment: 8 pages, 2 figures and 2 tables. Monthly Notices of the Royal Astronomical Society 201

    Exploring the Personal Reality of Disability and Recovery: A Tool for Empowering the Rehabilitation Process

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    People experiencing disability and chronic disease often feel powerless, relinquishing medical control to “more knowledgeable” professionals. This article presents qualitative and quantitative results from three individual patients experiencing an emerging procedure called Recovery Preference Exploration (RPE). To inspire greater patient involvement, self-direction, and individual choice, we instructed participants to create an imagined recovery path, exposing recovery preferences while learning about clinical rehabilitation concepts. Results uncovered important values and feelings about disability, providing a richer context for patient evaluation and treatment goal modification. Applying mixed methods, RPE is presented as an explanatory process for quantifying recovery preferences in a way that stimulates rich narrative of how people see different types of disabilities. RPE shows promise for increasing depth of discussions among patients, family, and clinicians. RPE may promote greater quality of life through patient empowerment by directed learning, increased communication, and enhanced self-knowledge

    Etude du comportement paramagnétique des actinides (IV) (Th, U, Np et Pu) en solution en présence de ligands

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    International audienceLa spectroscopie RMN est une technique capable de fournir des informations structurales sur des complexes mĂ©talliques en solution. Elle peut ĂȘtre appliquĂ©e Ă  l’analyse de petites molĂ©cules en chimie organique, de protĂ©ines (macros molĂ©cules) en biologie mais aussi en chimie nuclĂ©aire avec la nuclĂ©arisation des spectromĂštres [1]. La prĂ©sence d’un Actinide (An), avec des Ă©lectrons 5f non appariĂ©s, gĂ©nĂšre une modification du spectre RMN (un Ă©largissement et/ou une variation du dĂ©placement chimique des pics) caractĂ©ristique du paramagnĂ©tisme du cation.Dans le cas des complexes paramagnĂ©tiques de LnIII^{III} (Ă©lĂ©ments 4ff), le dĂ©placement chimique total ΔTOT\Delta _{TOT} est modĂ©lisĂ© par l’équation de Bleaney (Ă©quations (a) et (b)) [2]. Il dĂ©pend du dĂ©placement chimique paramagnĂ©tique induit ÎŽpara\delta _{para} qui peut ĂȘtre dĂ©composĂ© en deux contributions : un terme de contact ÎŽcont\delta _{cont} (dĂ©localisation de l’électron ff sur l’atome donneur du ligand) et un terme dipolaire ÎŽdip\delta _{dip} (interaction entre le spin Ă©lectronique et nuclĂ©aire Ă  travers l’espace). A partir de ce dernier terme, on peut dĂ©duire des informations structurales en utilisant les constantes de Bleaney

    THE ANALYSIS OF DECISION-MAKING PROCESS WITH 7P (A Quantitative-Descriptive Research of The Consumers of Happy Puppy Seturan Yogyakarta and Hello FKTV Yogyakarta)

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    Decision is the result of selecting one out of two or more options or available alternatives (Schiffman and Kanuk, 2000). As for other activities, decision-making can also be applied for choosing the right karaoke house to get entertainment. This paper is a quantitative-descriptive research of decision-making process of the consumers of Hello FKTV Yogyakarta and Happy Puppy Seturan, whose data are obtained from questionnaires spread to 30 consumers of Happy Puppy Seturan and Hello FKTV Yogyakarta who have come at least twice to both karaoke houses. Afterwards, the data are then analyzed using one of the marketingcommunication theories, which is Solomon’s consumer decision making process. The theory presumes that there are four steps in the process of consumer’s decision making process—problem/ need recognition,information search, evaluation of alternatives, and product choice. At the stage of evaluation of alternative, there is a paradigm called 7P, which tries to see a product or service from the viewpoint of marketing from seven different angles—product, price, place, promotion, people, process, and physical evidence. The 7P becomes the indicator to see and compare various alternatives which become the consideration of consumers in searching for information. It is then concluded that consumers fulfill their needs for karaoke by spending small amount of money through the utilization of discount voucher provided by Happy Puppy Seturan and Hello FKTV. Consumers give positive evaluation concerning the price or karaoke-room rental and the song collections. But other aspect such as foods and beverages are still evaluated negatively by the consumers, because of the tasteless of foods and the unaffordable price. Most of the consumers get the information concerning Happy Puppy Seturan and Hello FKTV form their friends and only small portion of the consumers seek for the information via social media. Promotion through social media can be one of the effective strategies to attract consumers, especially college students

    Control of Gene Expression by the Retinoic Acid-Related Orphan Receptor Alpha in HepG2 Human Hepatoma Cells

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    Retinoic acid-related Orphan Receptor alpha (RORα; NR1F1) is a widely distributed nuclear receptor involved in several (patho)physiological functions including lipid metabolism, inflammation, angiogenesis, and circadian rhythm. To better understand the role of this nuclear receptor in liver, we aimed at displaying genes controlled by RORα in liver cells by generating HepG2 human hepatoma cells stably over-expressing RORα. Genes whose expression was altered in these cells versus control cells were displayed using micro-arrays followed by qRT-PCR analysis. Expression of these genes was also altered in cells in which RORα was transiently over-expressed after adenoviral infection. A number of the genes found were involved in known pathways controlled by RORα, for instance LPA, NR1D2 and ADIPOQ in lipid metabolism, ADIPOQ and PLG in inflammation, PLG in fibrinolysis and NR1D2 and NR1D1 in circadian rhythm. This study also revealed that genes such as G6PC, involved in glucose homeostasis, and AGRP, involved in the control of body weight, are also controlled by RORα. Lastly, SPARC, involved in cell growth and adhesion, and associated with liver carcinogenesis, was up-regulated by RORα. SPARC was found to be a new putative RORα target gene since it possesses, in its promoter, a functional RORE as evidenced by EMSAs and transfection experiments. Most of the other genes that we found regulated by RORα also contained putative ROREs in their regulatory regions. Chromatin immunoprecipitation (ChIP) confirmed that the ROREs present in the SPARC, PLG, G6PC, NR1D2 and AGRP genes were occupied by RORα in HepG2 cells. Therefore these genes must now be considered as direct RORα targets. Our results open new routes on the roles of RORα in glucose metabolism and carcinogenesis within cells of hepatic origin

    Plasma BDNF Levels Vary in Relation to Body Weight in Females

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    Brain derived neurotrophic factor (BDNF) has been implicated in the pathophysiology of depression as well as neuropsychiatric and neurodegenerative disorders. Recent studies show a role of BDNF in energy metabolism and body weight regulation. We examined BDNF levels in plasma and cerebrospinal fluid (CSF) samples from age matched elderly depressed and control subjects. Also, the association of BDNF levels with age, gender, body weight, body mass index (BMI), and cognitive performance was evaluated. We did not find any significant differences in plasma and CSF BDNF levels between depressed and control subjects. Plasma BDNF levels were negatively correlated with age (but not with BMI and body weight), when analyses were performed including both depressed and control subjects. A significant reduction in plasma BDNF levels was observed in females as compared to male subjects, and the change in BDNF levels were significantly and positively related to body weight in females. Furthermore, significant increases in Total Recall and Delayed Recall values were found in females as compared to males. In conclusion, the lower BDNF levels observed in females suggest that changes in peripheral BDNF levels are likely secondary to an altered energy balance. However, further studies using larger sample size are warranted

    Re-evaluation of blood mercury, lead and cadmium concentrations in the Inuit population of Nunavik (Québec): a cross-sectional study

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    <p>Abstract</p> <p>Background</p> <p>Arctic populations are exposed to mercury, lead and cadmium through their traditional diet. Studies have however shown that cadmium exposure is most often attributable to tobacco smoking. The aim of this study is to examine the trends in mercury, lead and cadmium exposure between 1992 and 2004 in the Inuit population of Nunavik (Northern QuĂ©bec, Canada) using the data obtained from two broad scale health surveys, and to identify sources of exposure in 2004.</p> <p>Methods</p> <p>In 2004, 917 adults aged between 18 and 74 were recruited in the 14 communities of Nunavik to participate to a broad scale health survey. Blood samples were collected and analysed for metals by inductively coupled plasma mass spectrometry, and dietary and life-style characteristics were documented by questionnaires. Results were compared with data obtained in 1992, where 492 people were recruited for a similar survey in the same population.</p> <p>Results</p> <p>Mean blood concentration of mercury was 51.2 nmol/L, which represent a 32% decrease (p < 0.001) between 1992 and 2004. Mercury blood concentrations were mainly explained by age (partial r<sup>2 </sup>= 0.20; p < 0.0001), and the most important source of exposure to mercury was marine mammal meat consumption (partial r<sup>2 </sup>= 0.04; p < 0.0001). In 2004, mean blood concentration of lead was 0.19 ÎŒmol/L and showed a 55% decrease since 1992. No strong associations were observed with any dietary source, and lead concentrations were mainly explained by age (partial r<sup>2 </sup>= 0.20.; p < 0.001). Blood cadmium concentrations showed a 22% decrease (p < 0.001) between 1992 and 2004. Once stratified according to tobacco use, means varied between 5.3 nmol/L in never-smokers and 40.4 nmol/L in smokers. Blood cadmium concentrations were mainly associated with tobacco smoking (partial r<sup>2 </sup>= 0.56; p < 0.0001), while consumption of caribou liver and kidney remain a minor source of cadmium exposure among never-smokers.</p> <p>Conclusion</p> <p>Important decreases in mercury, lead and cadmium exposure were observed. Mercury decrease could be explained by dietary changes and the ban of lead cartridges use likely contributed to the decrease in lead exposure. Blood cadmium concentrations remain high and, underscoring the need for intensive tobacco smoking prevention campaigns in the Nunavik population.</p
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