8,271 research outputs found
Distribution function for seasonal and annual rainfall over India
Distribution functions for seasonal (southwest monsoon) and annual rainfall at 53 long-record stations in India have been obtained. It was found that the frequency distributions are right skewed. Tests for normality show that while normal distribution gives a good fit to seasonal and annual rainfall at stations in some parts of India it does not give a good fit to seasonal and annual rainfall at stations over the major portion of the country. Tests of goodness of fit of the Gamma distribution, however, clearly indicate that this distribution provides a good fit to seasonal and annual rainfall at stations in different parts of the country
Therapeutic implications of recombinant human erythropoietin in anaemic related clinical manifestations
The introduction of recombinant human erythropoietin (RHUEPO) has revolutionised the treatment strategies for patients suffering with anaemia of chronic renal disease and chronic heart failure. Clinicalstudies and several observational evidences have demonstrated that RHUEPO is also useful in various non-uraemic conditions including haematological and oncological disorders, prematurity, HIV infectionand preoperative therapies. The successful treatment of all the anaemic related malfunctions with recombinant human erythropoietin (RHUEPO) has become a standard treatment tool for dialysis patients and as an interesting therapeutic option for several forms of non-renal anaemia. As a conesquence of both, RHUEPO has achieved the highest annual sales worldwide and the potential of it increases its scope in the future prospective also
Global regularity properties of steady shear thinning flows
In this paper we study the regularity of weak solutions to systems of
p-Stokes type, describing the motion of some shear thinning fluids in certain
steady regimes. In particular we address the problem of regularity up to the
boundary improving previous results especially in terms of the allowed range
for the parameter p
Metabolic and transcriptomic analysis of Huntington's disease model reveal changes in intracellular glucose levels and related genes.
Huntington's Disease (HD) is a neurodegenerative disorder caused by an expansion in a CAG-tri-nucleotide repeat that introduces a poly-glutamine stretch into the huntingtin protein (mHTT). Mutant huntingtin (mHTT) has been associated with several phenotypes including mood disorders and depression. Additionally, HD patients are known to be more susceptible to type II diabetes mellitus (T2DM), and HD mice model develops diabetes. However, the mechanism and pathways that link Huntington's disease and diabetes have not been well established. Understanding the underlying mechanisms can reveal potential targets for drug development in HD. In this study, we investigated the transcriptome of mHTT cell populations alongside intracellular glucose measurements using a functionalized nanopipette. Several genes related to glucose uptake and glucose homeostasis are affected. We observed changes in intracellular glucose concentrations and identified altered transcript levels of certain genes including Sorcs1, Hh-II and Vldlr. Our data suggest that these can be used as markers for HD progression. Sorcs1 may not only have a role in glucose metabolism and trafficking but also in glutamatergic pathways affecting trafficking of synaptic components
Autoimmune lymphoproliferative syndrome in pregnancy: a case of favorable mother - fetal outcome in a well-controlled disease
The autoimmune lymphoproliferative syndrome(ALPS)is a disorder of abnormal lymphocyte survival caused by the dysregulation of theFasapoptotic pathway. The Fas geneis expressed at the maternal–fetal interface and is involved in the regulation of immune response and implantation. Altered Fas expression may result in altered apoptosis and, ultimately, affect both the immune response and implantation; it is in fact associated with recurrent pregnancy loss, preterm premature rupture of membranes and pre-eclampsia. Currently, there are over 500 cases of ALPS reported worldwide from various racial and ethnic backgrounds. Up to date, the published work contains no specific reports on pregnancy outcome in women affected by ALPS. We present a case of full-term uneventful pregnancy in a patient affected by ALPS. A specific clinical follow-up in a pregnant woman with primary immunologic disease is suggested
Influence of temperature on the dynamic and steady-shear rheology of pectin dispersions
The influence of temperature on the dynamic and steady-shear rheology of ionic polysaccharides, high-methoxyl and low-methoxyl pectins, has been studied and compared with the behaviour of locust bean gum, a virtually neutral biopolymer. Using the time-temperature superposition principle, the rheological parameters were reduced to an arbitrary reference temperature. Activation energies were calculated and their dependence on temperature and shear rate analysed. Concerning the viscosity dependence on temperature, two approaches have been considered: one associated with the theory of absolute reaction rates leading to an Arrhenius type equation, and the other associated with the free volume theory, expressed by the Williams-Landel-Ferry equation. The difficulties encountered in the superposition of the dynamic properties of the pectin dispersions, the high activation energies, yield values and elastic plateau at low oscillatory frequency, are consistent with a macromolecular organization of these polymers dominated by important aggregation phenomena, which could be attributed to important intermolecular interactions like hydrogen bonding and hydrophobic interactions, especially in conditions of low degree of ionization of the carboxylic groups
High-resolution spectroscopy of the R Coronae Borealis and Other Hydrogen Deficient Stars
High-resolution spectroscopy is a very important tool for studying stellar
physics, perhaps, particularly so for such enigmatic objects like the R Coronae
Borealis and related Hydrogen deficient stars that produce carbon dust in
addition to their peculiar abundances.
Examples of how high-resolution spectroscopy is used in the study of these
stars to address the two major puzzles are presented: (i) How are such rare
H-deficient stars created? and (ii) How and where are the obscuring soot clouds
produced around the R Coronae Borealis stars?Comment: 16 pages, 9 figures, Astrophysics and Space Science Proceedings,
Springer-Verlag, Berlin, 201
Kinetics and thermal behaviour of the structure formation process in HMP/sucrose gelation
The concentration and temperature dependence of the gelation kinetics of high-methoxyl pectin (HMP; 60% sucrose, pH 3) was investigated using measurements of small-amplitude oscillatory shear. The rate of gelation close to the gel point can be described as a second-order rate process using the kinetic model of Ross-Murphy (Carbohydr. Polym. 1991, 14, 281) and a critical exponent close to that predicted by the percolation approach. The modulus after a long ageing time showed a power concentration dependence with an exponent around 3.1, higher than the classical square of concentration dependence, which was probably either due to the non-equilibrium state of the HMP gels even after long ageing times, or due to the proximity of the concentration range studied to the critical gelling concentration. The gelation rate of HMP/sucrose systems is strongly dependent on the temperature. An Arrhenius relationship was applied to describe this dependence. Two different processes are proposed to explain the discontinuity observed, each one having rates with different temperature dependence. The applicable kinetics at longer times are quite different, with a lower dependence on polymer concentration and ageing temperature. A non-isothermal kinetic model was used to describe the gelation process of the HMP/sucrose system during cooling
On the well-posedness of the stochastic Allen-Cahn equation in two dimensions
White noise-driven nonlinear stochastic partial differential equations
(SPDEs) of parabolic type are frequently used to model physical and biological
systems in space dimensions d = 1,2,3. Whereas existence and uniqueness of weak
solutions to these equations are well established in one dimension, the
situation is different for d \geq 2. Despite their popularity in the applied
sciences, higher dimensional versions of these SPDE models are generally
assumed to be ill-posed by the mathematics community. We study this discrepancy
on the specific example of the two dimensional Allen-Cahn equation driven by
additive white noise. Since it is unclear how to define the notion of a weak
solution to this equation, we regularize the noise and introduce a family of
approximations. Based on heuristic arguments and numerical experiments, we
conjecture that these approximations exhibit divergent behavior in the
continuum limit. The results strongly suggest that a series of published
numerical studies are problematic: shrinking the mesh size in these simulations
does not lead to the recovery of a physically meaningful limit.Comment: 21 pages, 4 figures; accepted by Journal of Computational Physics
(Dec 2011
Role of the reversible electrochemical deprotonation of phosphate species in anaerobic biocorrosion of steels
Sulphate reducing bacteria are known to play a major role in anaerobic microbiological influenced
corrosion of steels, but mechanisms behind their influence are still source of debates as certain
phenomena remain unexplained. Some experiments have shown that hydrogen consumption by SRB
or hydrogenase increased the corrosion rate of mild steel. This was observed only in the presence of
phosphate species. Here the cathodic behaviour of phosphate species on steel was studied to elucidate
the role of phosphate in anaerobic corrosion of steel. Results showed: a linear correlation
between reduction waves in linear voltammetry and phosphate concentration at a constant pH value;
that phosphate ions induced considerable anaerobic corrosion of mild steel, which was sensitive to
hydrogen concentration in the solution; and that the corrosion potential of stainless steel in presence
of phosphate was shifted to more negative values as molecular hydrogen was added to the atmosphere
in the reaction vessel. Phosphate species, and possibly other weak acids present in biofilms,
are suggested to play an important role in the anaerobic corrosion of steels via a reversible mechanism
of electrochemical deprotonation that may be accelerated by hydrogen removal
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