3,424 research outputs found
FADS Gene Cluster Polymorphisms: Important Modulators of Fatty Acid Levels and Their Impact on Atopic Diseases
Long-chain polyunsaturated fatty acids (LC-PUFAs) play an important role in several physiological processes and their concentration in phospholipids has been associated with several complex diseases, such as atopic disease. The level and composition of LC-PUFAs in the human body is highly dependent on their intake in the diet or on the intake of fatty acid precursors, which are endogenously elongated and desaturated to physiologically active LC-PUFAs. The most important enzymes in this reaction cascade are the Delta(5) and Delta(6) desaturase. Several studies in the last few years have revealed that single nucleotide polymorphisms (SNPs) in the 2 desaturase encoding genes (FADS1 and FADS2) are highly associated with the concentration of omega-6 and omega-3 fatty acids, showing that beside nutrition, genetic factors also play an important role in the regulation of LC-PUFAs. This review focuses on current knowledge of the impact of genetic polymorphisms on LC-PUFA metabolism and on their potential role in the development of atopic diseases. Copyright (c) 2009 S. Karger AG, Base
Spin correlation functions in random-exchange s=1/2 XXZ chains
The decay of (disorder-averaged) static spin correlation functions at T=0 for
the one-dimensional spin-1/2 XXZ antiferromagnet with uniform longitudinal
coupling and random transverse coupling is investigated
by numerical calculations for ensembles of finite chains. At (XX
model) the calculation is based on the Jordan-Wigner mapping to free lattice
fermions for chains with up to N=100 sites. At Lanczos
diagonalizations are carried out for chains with up to N=22 sites. The
longitudinal correlation function is found to exhibit a
power-law decay with an exponent that varies with $\Delta$ and, for nonzero
$\Delta$, also with the width of the $\lambda_i$-distribution. The results for
the transverse correlation function show a crossover from
power-law decay to exponential decay as the exchange disorder is turned on.Comment: RevTex manuscript (7 pages), 4 postscript figure
Wie entgeht man der Armuth? : Eine Anweisung wie man mit Sicherheit zu einem ehrenhaften Wohlstande gelangen, also sich vor Armuth bewahren und selbst wieder entreiĂen kann
Import pathways of precursor proteins into mitochondria
The precursor of porin, a mitochondrial outer membrane protein, competes for the import of precursors destined for the three other mitochondrial compartments, including the Fe/S protein of the bc1- complex (intermembrane space), the ADP/ATP carrier (inner membrane), subunit 9 of the F0-ATPase (inner membrane), and subunit beta of the F1- ATPase (matrix). Competition occurs at the level of a common site at which precursors are inserted into the outer membrane. Protease- sensitive binding sites, which act before the common insertion site, appear to be responsible for the specificity and selectivity of mitochondrial protein uptake. We suggest that distinct receptor proteins on the mitochondrial surface specifically recognize precursor proteins and transfer them to a general insertion protein component (GIP) in the outer membrane. Beyond GIP, the import pathways diverge, either to the outer membrane or to translocation contact-sites, and then subsequently to the other mitochondrial compartments
Temporal Changes in Total Serum Immunoglobulin E Levels in East German Children and the Effect of Potential Predictors
Background: Elevated total serum immunoglobulin E (IgE) levels are a prominent feature of allergic and parasitic diseases. An epidemiologic study was conducted in East German children to describe trends in the development of total serum IgE levels and analyze the impact of potential determinants. Methods: The study consisted of three cross-sectional surveys in 1992-1993, 1995-1996 and 1998-1999 and was conducted in three areas of the former German Democratic Republic. In total, 8,051 questionnaires were completed by the parents of children aged 5-14 years, supplying information on allergic symptoms and potential risk factors. A total of 5,918 measurements of total serum IgE and specific IgE to 5 common aeroallergens were available from 4,353 schoolchildren. Generalized estimating equations were applied to data from all children and stratified for atopic and nonatopic children to identify trends and estimate the effect of potential determinants on total IgE. Results: Total serum IgE levels decreased significantly with a linear trend in East German schoolchildren between 1992 and 1999, the effect being stronger in nonatopic children. The following factors were associated with lower total serum IgE levels: female gender, living in a household with fewer than 4 people, no history of helminth infestation, younger age group (5-7 years), no parental allergy and high socioeconomic status. No association was seen for `smoking at home' and close contact to pets. Conclusion: Total serum IgE declined parallel to helminth infestation; however, the latter explained the decrease only in part. Furthermore, total IgE developed in an opposite direction to specific IgE, indicating that it has determinants other than allergic sensitization. Copyright (C) 2011 S. Karger AG, Base
Laying off or Not? the Influence of Framing and Economics Education
This paper provides a critical re-examination of Rubinstein's survey (Rubinstein; Economic Journal 2006), in which he questions the way economics is taught. The observations obtained in our new survey cast some doubts on the original findings, and, in particular, question Rubinstein's conjecture that our students' views on economic issues are influenced by the way we teach economics.
Game or frame? Incentives in modified Dictator Games
We use modified dictator games in which the productivity of taking or giving is varied. Subjects have to decide which of the different games will be payoff relevant in the end. We can show that the behavior of dictators does not depend on the productivity of their gifts, but that their behavior is strongly influenced by the right to choose the relevant game. If the recipients have the right to choose, the dictators become more generous
Combinations of Epidemiological and Experimental Studies in Air Pollution Research: A Narrative Review
Scientific literature is evolving to include more systematic reviews that encompass epidemiological and experimental papers so that the whole picture can be examined. The aim of this narrative review is to bridge that gap by combining epidemiological and experimental studies based on the same setting: Examples of Bitterfeld, Utah Valley, Beijing Olympic Games, and Viadana. This review looks at four examples that incorporate multiple epidemiological and experimental papers about air pollution exposure and health effects. The Bitterfeld (spatial) and Utah Valley (temporal) examples showed that particle composition causes the biggest difference in lung injury. In Beijing, a temporal difference of before/after and during the Olympics showed that traffic and industry air pollution-related health effects like lung cancer and cardiovascular disease could be reduced by improvement of air quality. The Viadana example showed a spatial difference in respiratory injury caused by particle composition and interactions with genotoxicity. Combining experimental and epidemiological methods gives a more in-depth look into the whole picture of exposure and health effects. Our review exemplifies the strength of this strategy and encourages further use of it
Programma, Quo Rector Academiae Rostochianae Joach. Henricus Sibrand ... ad honorificas, solemnesque exequias, quas Viro ... Dno. Henrico Beccero, Aedis Jacobeae Pastori vigilantissimo ... Vidua Relicta Moestissima, d. 16. Februar. anni 1720. paratas cupit, Omnes Omnium Ordinum Cives Academicos, sedulo, et peramanter invitat, convocatque
Schnellschaltende Aktoren fĂŒr adaptive Sicherheitssysteme im Kraftfahrzeugbau
Der Einsatz von adaptiv arbeitenden Sicherheitssystemen im Kraftfahrzeugbereich wird stĂ€ndig zunehmen. Im vorliegenden Projekt soll ein einfach arbeitendes und schnellschaltendendes Aktorprinzip mit Hilfe des Einsatzes von FormgedĂ€chtniselementen realisiert werden. Ein solch kostengĂŒnstiges und sehr sicher arbeitendes System wird nicht nur vorhandene teure und aufwendige Systeme ersetzen können, sondern es wird auch durch die hohe Integrierbarkeit und gĂŒnstige Recyclebarkeit den Einsatz von Aktoren im Kraftfahrzeugbereich erhöhen. Gegenstand dieses Projektes ist die werkstoffkundliche Entwicklung eines adaptiven Sicherheitssystems mit FormgedĂ€chtnislegierungen zum Einsatz in Kraftfahrzeugen. Durch die spontane Umwandlung der FGL beim Ăberschreiten einer kritischen Temperatur, können sehr schnell und funktionssicher Linearbewegungen ausgefĂŒhrt werden. Das Problem der LangzeitstabilitĂ€t des FormgedĂ€chtniseffektes soll in diesem Forschungsvorhaben betrachtet werden. Hierzu werden durch Auslagerungsversuche sowohl die Auswirkungen von Ausscheidungen, als auch die metallkundlichen HintergrĂŒnde fĂŒr die Entstehung der Ausscheidungen betrachtet. Durch die Kenntnis der ablaufenden VorgĂ€nge sollte es möglich sein Legierungen einzusetzen, welche die erforderliche LangzeitstabilitĂ€t aufweisen. In einem weiteren Projektschritt sollen SchnellerwĂ€rmungssysteme entwickelt und erprobt werden, die es ermöglichen mit dem vorhandenen Bordstromnetz eine schnellstmögliche und sichere ErwĂ€rmung der FG-Elemente zu gewĂ€hrleisten
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