180 research outputs found
Effect of diet on maintenance of acid-basal balance in blood of dairy cows
High-performance breeds of ruminants often exhibit production disorders which can be accompanied by a disturbed acid-basal balance. Most of the disorders in the acid-basal balance are closely related to digressions in the diet norms of these animals. A deficiency or surplus of energy equally cause disorders in the acid-basal status of the organism. Metabolic acidosis is the most frequent of the four types of basic disorders in the acid-basal balance in ruminants. It appears as a consequence of rumen acidosis, ketosis, or diarrhea. Acute disorders in the acid-basal balance are far more dangerous than chronic ones. Therapy of the basic diseases is generally sufficient compensation for the effects of the acid-basal disorders, but in certain cases it is necessary to perform alkalization, that is, acidification of the rumen content using the necessary preparations
A process-based analysis of the suitability of copula types for peak-volume flood relationships
The work aims at analyzing the bivariate relationship between flood peaks
and flood volumes, with a particular focus on the type and seasonality of
flood generation processes. Instead of the usual approach that deals with an
analysis of the annual maxima of flood events, the current analysis includes
all independent flood events in a catchment. Flood events are considered
independent when they originate from distinguishably different
synoptic/meteorological situations. The target region is located in the
northern part of Austria, and consists of 72 small and mid-sized catchments.
On the basis of the discharge measurements with a time resolution of 1 h
from the period 1976–2007, independent flood events were identified and were
assigned to one of the three following flood generation type categories:
synoptic floods, flash floods and snowmelt floods. These were subsequently
divided into two seasons, thereby separating predominantly rainfall-fed and
snowmelt-fed floods. Nine frequently-used copula types were locally fitted
to the samples of the flood type and seasonal data. Their goodness-of-fit
was examined locally as well as analyzed in a regional scope. It was
concluded that (i) treating flood processes separately is beneficial for the
statistical analysis; (ii) suitability patterns of acceptable copula types
are distinguishably different for the seasons/flood types considered, (iii)
the Clayton and Joe copulas shows an unacceptable performance for all the
seasons/flood types in the region; (iv) the rejection rate of the other
copula types depends on the season/flood type and also on the sample size;
(v) given that usually more than one statistically suitable dependence model
exists, an uncertainty analysis of the design values in the engineering
studies resulting from the choice of model seems unavoidable; (vi) reducing
uncertainty in the choice of model could be attempted by a deeper
hydrological analysis of the dependence structure between flood peaks and
volumes in order to give hydrological support to the decision on model's
suitability in specific regions and for typical flood generation mechanisms
Rate of lipid peroxidation in brain and liver tissues and the total antioxidant status of blood plasma in developing chicks
Age-related changes of tissue lipid peroxidation (LPO) of liver and brain, as well as plasma antioxidant capacity of broiler chicken cockerels were investigated. Tissue LPO was characterised by the spectrophotometric assessment of thiobarbituric acid reactive substances (TBARS). Plasma antioxidant power was evaluated by the measurement of total antioxidant status (TAS). Newly hatched broiler chicks had similar TAS value (1.19 mmol/l) as newborns of mammalian species. Significant changes (p < 0.05) were observed in the time course of all parameters. Tissue TBARS concentration was higher in the brain than in the liver at hatching, while the latter organ was found to have more effective antioxidant defence during embryonic life. The concentration of TBARS increased up to the 10th day in the liver but only up to the 21st day in the brain, and the former was accompanied by an approximately 50% decrease of plasma antioxidant capacity. This suggests that the liver plays an important role in forming the antioxidant defence mechanisms of the blood plasma in broiler chicks
Lateral Separation of Macromolecules and Polyelectrolytes in Microlithographic Arrays
A new approach to separation of a variety of microscopic and mesoscopic
objects in dilute solution is presented. The approach takes advantage of unique
properties of a specially designed separation device (sieve), which can be
readily built using already developed microlithographic techniques. Due to the
broken reflection symmetry in its design, the direction of motion of an object
in the sieve varies as a function of its self-diffusion constant, causing
separation transverse to its direction of motion. This gives the device some
significant and unique advantages over existing fractionation methods based on
centrifugation and electrophoresis.Comment: 4 pages with 3 eps figures, needs RevTeX 3.0 and epsf, also available
in postscript form http://cmtw.harvard.edu/~deniz
Pressure Induced Quantum Critical Point and Non-Fermi-Liquid Behavior in BaVS3
The phase diagram of BaVS3 is studied under pressure using resistivity
measurements. The temperature of the metal to nonmagnetic Mott insulator
transition decreases under pressure, and vanishes at the quantum critical point
p_cr=20kbar. We find two kinds of anomalous conducting states. The
high-pressure metallic phase is a non-Fermi liquid described by Delta rho = T^n
where n=1.2-1.3 at 1K < T < 60K. At p<p_cr, the transition is preceded by a
wide precursor region with critically increasing resistivity which we ascribe
to the opening of a soft Coulomb gap.Comment: 4 pages, 5 eps figures, problem with figure correcte
Deviations in Circulating TNF α
Objectives. Tumor necrosis factor alpha (TNFα) plays a pivotal role in the inflammatory host response. The serum-level of TNFα and the production of TNFα by lympho/monocytes, however, seem to show high individual variations. The goal of the present study was to investigate the variations and inducibility of TNFα-activity in two age-groups of healthy volunteers. Methods. Sixty elderly, healthy volunteers were studied. These persons were free of malignant diseases, and within three months, they did not have any trauma or inflammatory disease and were not taking any steroids or nonsteroid anti-inflammatory drugs. Thirty young volunteers were also included. Blood samples were taken; lympho/monocytes were separated and cultured with or without endotoxin (LPS) stimulation. Serum and culture supernatant TNFα levels were determined by bioassay using WEHI 164 cells. Results. The results indicated significant individual variations in TNFα levels of healthy volunteers irrespective of age. Subgroups with low, middle, and high serum TNF-levels were distinguished. In about 50% of volunteers with low serum-TNFα activity, LPS stimulation failed to increase the TNFα production by isolated lympho/monocytes. Conclusion. Our data suggest a chance to select individuals with enhanced sensitivity for septic complications
30 years of collaboration
We highlight some of the most important cornerstones of the long standing and very fruitful collaboration of the Austrian Diophantine Number Theory research group and the Number Theory and Cryptography School of Debrecen. However, we do not plan to be complete in any sense but give some interesting data and selected results that we find particularly nice. At the end we focus on two topics in more details, namely a problem that origins from a conjecture of Rényi and Erdős (on the number of terms of the square of a polynomial) and another one that origins from a question of Zelinsky (on the unit sum number problem). This paper evolved from a plenary invited talk that the authors gaveat the Joint Austrian-Hungarian Mathematical Conference 2015, August 25-27, 2015 in Győr (Hungary)
Phonons and related properties of extended systems from density-functional perturbation theory
This article reviews the current status of lattice-dynamical calculations in
crystals, using density-functional perturbation theory, with emphasis on the
plane-wave pseudo-potential method. Several specialized topics are treated,
including the implementation for metals, the calculation of the response to
macroscopic electric fields and their relevance to long wave-length vibrations
in polar materials, the response to strain deformations, and higher-order
responses. The success of this methodology is demonstrated with a number of
applications existing in the literature.Comment: 52 pages, 14 figures, submitted to Review of Modern Physic
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