575 research outputs found
Adipose tissue as a medium for epidemiologic exposure assessment.
In the United States, adipose tissue is rarely used as a medium for assessment of prior exposures in epidemiologic studies. Adipose tissue aspirations are in general less invasive and carry less risk than phlebotomy. Tissue samples can be analyzed for a wide number of epidemiologically important exposures. Beyond reflecting long-term energy balance, this tissue offers a relatively stable depot of triglyceride and fat-soluble substances, such as fat-soluble vitamins, and pesticides. As a tissue it represents the greatest reservoir of carotenoids in the body. Halogenated hydrocarbons may be measured in concentrations of hundreds-fold greater than those in blood of the same individuals. The composition of adipose tissue also reflects the long-term dietary intakes of a number of essential fatty acids. The turnover times of all of these substances in adipose tissue remain under-researched. Sampling and storage of adipose tissue, homogeneity of sampling sites, turnover times, and the effects of diet, age, gender, race, hormones, and disease on adipose tissue composition are discussed in this review of current knowledge about adipose tissue stability. Experience in the use of adipose tissue sampling in epidemiologic studies in various countries has shown that it is simple to conduct, requires little training, carries little risk, and does not result in excessive participant refusal
NMR study of a bimesogenic liquid crystal with two nematic phases
Recent interest in bimesogenic liquid crystals showing two nematic phases has led us to investigate the nematic mean-field interactions in these nematic phases by using rigid solutes as probes. The nematic potential that is modelled by two independent Maier-Saupe terms is successful in fitting the observed dipolar couplings (order parameters) of para-, meta- and ortho-dichlorobenzene solutes in both the nematic phases of 39 wt% of 4-n-pentyl-4âČ-cyanobiphenyl (5CB) in α,Ï-bis(4-4âČ-cyanobiphenyl)nonane (CB_C9_CB) to better than the 5% level. The derived liquid-crystal potential parameters Gâ and Gâ for each solute in the N and Ntb phases will be discussed. The most interesting observation is that G1 (associated with size and shape interactions) is almost constant in the Ntb phase, whereas Gâ (associated with longer-range electrostatic interactions) has large variation, even changing sign
Rentenpaket: Die Bundesregierung auf Irrwegen
Das Gesetz ĂŒber Leistungsverbesserungen in der Gesetzlichen Rentenversicherung ist am 1.7.2014 in Kraft getreten. Zu einer Reduktion der Altersarmut - wie die Aussagen im Bundestagswahlkampf 2013 vermuten lieĂen - trĂ€gt zumindest die abschlagsfreie Rente mit 63 nicht bei. Die Autoren aus dem SachverstĂ€ndigenrat Wirtschaft bewerten die einzelnen MaĂnahmen des Gesetzes differenziert und befĂŒrchten hohe Mehrausgaben, die die ZukunftsfĂ€higkeit des Rentensystems gefĂ€hrden.In the summer of 2014 Germany will witness the most substantial expansion of pension expenditures since the 1950s. Yet, while this reform package was motivated mainly by the dismal prospect of rising old age poverty rates, it does little to alleviate this problem. On the contrary, its two central elements, an expansion of the pension claims of mothers whose children were born before 1992, and access to early retirement at age 63 for workers with a long insurance history, tend to benefi t rather privileged groups of the insured. These measures endanger the sustainability of the German pension system and will necessitate future generations to work even longer than would have been the case otherwise
Proceedings of the inaugural International Summit for Medical Nutrition Education and Research
© 2016 The Royal Society for Public Health Medical Nutrition Education (MNE) has been identified as an area with potential public health impact. Despite countries having distinctive education systems, barriers and facilitators to effective MNE are consistent across borders, demanding a common platform to initiate global programmes. A shared approach to supporting greater MNE is ideal to support countries to work together. In an effort to initiate this process, the Need for Nutrition Education/Innovation Programme group, in association with their strategic partners, hosted the inaugural International Summit on Medical Nutrition Education and Research on August 8, 2015 in Cambridge, UK. Speakers from the UK, the USA, Canada, Australia, New Zealand, Italy, and India provided insights into their respective countries including their education systems, inherent challenges, and potential solutions across two main themes: (1) Medical Nutrition Education, focused on best practice examples in competencies and assessment; and (2) Medical Nutrition Research, discussing how to translate nutrition research into education opportunities. The Summit identified shared needs across regions, showcased examples of transferrable strategies and identified opportunities for collaboration in nutrition education for healthcare (including medical) professionals. These proceedings highlight the key messages presented at the Summit and showcase opportunities for working together towards a common goal of improvement in MNE to improve public health at large
Choice of resident costimulatory molecule can influence cell fate in human naĂŻve CD4+ T cell differentiation
With antigen stimulation, naĂŻve CD4+ T cells differentiate to several effector or memory cell populations, and cytokines contribute to differentiation outcome. Several proteins on these cells receive costimulatory signals, but a systematic comparison of their differential effects on naĂŻve T cell differentiation has not been conducted. Two costimulatory proteins, CD28 and ICAM-1, resident on human naĂŻve CD4+ T cells were compared for participation in differentiation. Under controlled conditions, and with no added cytokines, costimulation through either CD3+CD28 or CD3+ICAM-1 induced differentiation to T effector and T memory cells. In contrast, costimulation through CD3+ICAM-1 induced differentiation to Treg cells whereas costimulation through CD3+CD28 did not
The route of priming influences the ability of respiratory virusâspecific memory CD8+ T cells to be activated by residual antigen
After respiratory virus infections, memory CD8+ T cells are maintained in the lung airways by a process of continual recruitment. Previous studies have suggested that this process is controlled, at least in the initial weeks after virus clearance, by residual antigen in the lung-draining mediastinal lymph nodes (MLNs). We used mouse models of influenza and parainfluenza virus infection to show that intranasally (i.n.) primed memory CD8+ T cells possess a unique ability to be reactivated by residual antigen in the MLN compared with intraperitoneally (i.p.) primed CD8+ T cells, resulting in the preferential recruitment of i.n.-primed memory CD8+ T cells to the lung airways. Furthermore, we demonstrate that the inability of i.p.-primed memory CD8+ T cells to access residual antigen can be corrected by a subsequent i.n. virus infection. Thus, two independent factors, initial CD8+ T cell priming in the MLN and prolonged presentation of residual antigen in the MLN, are required to maintain large numbers of antigen-specific memory CD8+ T cells in the lung airways
Numerical study of the THM effects on the near-field safety of a hypothetical nuclear waste repositoryâBMT1 of the DECOVALEX III project. Part 1: Conceptualization and characterization of the problems and summary of results
11 pagesInternational audienceGeological disposal of the spent nuclear fuel often uses the concept of multiple barrier systems. In order to predict the performance of these barriers, mathematical models have been developed, verified and validated against analytical solutions, laboratory tests and field experiments within the international DECOVALEX III project. These models in general consider the full coupling of thermal (T), hydraulic (H) and mechanical (M) processes that would prevail in the geological media around the repository. For Bench Mark Test no. 1 (BMT1) of the DECOVALEX III project, seven multinational research teams studied the implications of coupled THM processes on the safety of a hypothetical nuclear waste repository at the near-field and are presented in three accompanying papers in this issue. This paper is the first of the three companion papers, which provides the conceptualization and characterization of the BMT1 as well as some general conclusions based on the findings of the numerical studies. It also shows the process of building confidence in the mathematical models by calibration with a reference TâHâM experiment with realistic rock mass conditions and bentonite properties and measured outputs of thermal, hydraulic and mechanical variables
Nutrition Education in U.S. Medical Schools: Latest Update of a National Survey
To quantify the number of required hours of nutrition education at U.S. medical schools and the types of courses in which the instruction was offered, and to compare these results with results from previous surveys
Numerical study of the THM effects on the near-field safety of a hypothetical nuclear waste repositoryâBMT1 of the DECOVALEX III project. Part 2: Effects of THM coupling in continuous and homogeneous rocks
14 pagesInternational audienceAn evaluation of the importance of the thermo-hydro-mechanical couplings (THM) on the performance assessment of a deep underground radioactive waste repository has been made as a part of the international DECOVALEX III project. It is a numerical study that simulates a generic repository configuration in the near field in a continuous and homogeneous hard rock. A periodic repository configuration comprises a single vertical borehole, containing a canister surrounded by an over-pack and a bentonite layer, and the backfilled upper portion of the gallery. The thermo-hydro-mechanical evolution of the whole configuration is simulated over a period of 100 years. The importance of the rock mass's intrinsic permeability has been investigated through scoping calculations with three values: 10â17, 10â18 and 10â19 m2. Comparison of the results predicted by fully coupled THM analysis as well as partially coupled TH, TM and HM analyses, in terms of several predefined indicators of importance for performance assessment, enables us to identify the effects of the different combinations of couplings, which play a crucial role with respect to safety issues. The results demonstrate that temperature is hardly affected by the couplings. In contrast, the influence of the couplings on the mechanical stresses is considerable
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