Search results for "Variation"
showing 10 items of 2124 documents
A simple high-performance liquid chromatography (HPLC) method for the measurement of pyridoxal-5-phosphate and 4-pyridoxic acid in human plasma.
2014
Abstract Background Low concentration of plasma pyridoxal-5-phosphate (PLP) is associated with hyperhomocysteinemia and inflammation. Most methods for the measurement of plasma PLP require large specimen volume and involve the use of toxic reagents. Methods We have developed a HPLC method for the measurement of PLP and 4-pyridoxic acid (4-PA) in plasma, which requires small specimen volume. The samples are prepared without adding any toxic reagents. Furthermore, we have examined whether intake of vitamin B 6 affects the concentration of plasma PLP and 4-PA. Results The coefficient of variation of the method was 6% and the recovery of the added vitamin in plasma was about 100%. The concentra…
Palaeomagnetic investigations of the tertiary and quaternary igneous rocks: IV The tertiary volcanic rocks of the Tokaji mountains, Hungary
1971
Measurements are reported from samples collected at twenty three sites in the Tokaj mountains of north-eastern Hungary. The simplest interpretation of the results is in terms of geomagnetic field reversals, for there is no petrological or magnetic evidence of self reversal or of correlation of oxidation state and magnetic sign. Four magnetic zones satisfy the minimum stratigraphic requirements, speculative use of these zones against theHeirtzler et al. magnetic time scale as a control suggests locating the Miocene-Pliocene boundary at 11.75 my. However it seems probable that much of the lower Sarmatian is not represented in the Tokaj samples, although the scatter of individual readings sugg…
Voluntary associations and trust in Finland
2009
The article is an empirical study of the hypothesis put forward in theories of social capital, according to which voluntary associations have a positive e ect on trust in people. The central research question of the article is: are association memberships or active participation related to trust towards people in Finland? Looking at the number of association memberships and association registrations shows that association life has been active in Finland. The international comparison shows that particularly in the Nordic countries, people participate in associations on a vast scale. However, it is also important to note that while the old politicalideological associations have lost some of t…
Losing weight after menopause with minimal aerobic training and mediterranean diet
2020
Objective: It is a common belief that menopausal women have greater difficulty losing weight. The aim of this study was to assess the efficacy of a Mediterranean diet (MD) to promote weight loss in postmenopausal women. All participants were prescribed a hypocaloric traditional MD, tailored to the individual. Subjects were asked not to begin any kind of physical activity. Body composition was measured at the beginning and after 8 weeks of treatment. In total, 89 women (age 52.8 ±
Temperature-dependence of spontaneous mutation rates
2020
Mutation is the source of genetic variation and the fundament of evolution. At the interphase of ecology and evolution, temperature has long been suggested to have a direct impact on realised spontaneous mutation rates. The question is whether mutation rates can be a species-specific constant under variable environmental conditions, such as variation of the ambient temperature. By combining mutation accumulation with whole genome sequencing in a multicellular organism, we provide empirical support to reject this null hypothesis. Instead mutation rates depend on temperature in a U-shaped manner with increasing rates towards both temperature extremes. This relation has important implications …
Fermentative stress adaptation of hybrids within the Saccharomyces sensu stricto complex.
2008
Along the fermentation process yeasts are affected by a succession of stress conditions that affect their viability and fermentation efficiency. Among the stress conditions the most relevant are high sugar concentration and low pH in musts, temperature and, as fermentation progresses, ethanol accumulation. Nowadays, due to the demanding nature of modern winemaking practices and sophisticated wine markets, there is an ever-growing search for particular wine yeast strains possessing a wide range of optimized, improved or novel enological characteristics. Traditionally, the species S. cerevisiae and S. bayanus within the Saccharomyces sensu stricto species are considered some of the most impor…
Differences in the glucose and fructose consumption profiles in diverse Saccharomyces wine species and their hybrids during grape juice fermentation
2009
7 pages, 4 figures, 5 tables.
Reading performance and its developmental trajectories during the first and the second grade
2004
Abstract This study examined children’s reading performance and its developmental trajectories during the first and the second grade. Ninety children were tested five times on word reading and reading comprehension. Qualitatively different groups were identified through cluster analysis: Competent, Technical, and Poor Readers. The results showed that the group membership in the Competent and Technical Reader groups was relatively stable across time but less so for the Poor Reader group. Moreover, seven reading paths were identified of which three were comparatively regressive paths. The results emphasize the importance of taking into account individual variation in reading trajectories duri…
A compliant visco-plastic particle contact model based on differential variational inequalities
2013
This work describes an approach to simulate contacts between threedimensional shapes with compliance and damping using the framework of the differential variational inequality theory. Within the context of nonsmooth dynamics, we introduce an extension to the classical set-valued model for frictional contacts between rigid bodies, allowing contacts to experience local compliance, viscosity, and plasticization. Different types of yield surfaces can be defined for various types of contact, a versatile approach that contains the classic dry Coulomb friction as a special case. The resulting problem is a differential variational inequality that can be solved, at each integration time step, as a v…
Shock-capturing schemes: high accuracy versus total-variation boundedness
2007
In this reseach work we analyze the total variation growth of some high order accurate reconstruction procedures used for the design of shock capturing schemes. This study allows to measure how oscillatory a high order accurate method is in terms of the basic elementary function chosen to increase the order of accuracy. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)