2,445 research outputs found
HIV/Aids epidemic in India and predicting the impact of the national response: mathematical modeling and analysis
After two phases of AIDS control activities in India, the third phase of the National AIDS Control Programme (NACP III) was launched in July 2007. Our focus here is to predict the number of people living with HIV/AIDS (PLHA) in India so that the results can assist the NACP III planning team to determine appropriate targets to be activated during the project period (2007-2012). We have constructed a dynamical model that captures the mixing patterns between susceptibles and infectives in both low-risk and high-risk groups in the population. Our aim is to project the HIV estimates by taking into account general interventions for susceptibles and additional interventions, such as targeted interventions among high risk groups, provision of anti-retroviral therapy, and behavior change among HIV-positive individuals. Continuing the current level of interventions in NACP II, the model estimates there will be 5.06 million PLHA by the end of 2011. If 50 percent of the targets in NACP III are achieved by the end of the above period then about 0.8 million new infections will be averted in that year. The current status of the epidemic appears to be less severe compared to the trend observed in the late 1990s. The projections based on the second phase and the third phase of the NACP indicate prevention programmes which are directed towards the general and high-risk populations, and HIV-positive individuals will determine the decline or stabilization of the epidemic. Model based results are derived separately for the revised HIV estimates released in 2007. We perform a Monte Carlo procedure for sensitivity analysis of parameters and model validation. We also predict a positive role of implementation of anti-retroviral therapy treatment of 90 percent of the eligible people in the country. We present methods for obtaining disease progression parameters using convolution approaches. We also extend our models to age-structured populations
Anti-inflammatory activity of theophylline on carrageenan-induced paw edema in male wistar rats
Background: Evaluate the anti-inflammatory property of theophylline on rat hind paw edema using carrageenan-induced acute inflammatory model.Methods: Wistar male rats (150-200 gm) were divided into 7 groups- 3 standard groups, 3 test groups and 1 control group. Each group consists of six rats. A control group was treated with 0.2ml of normal saline, 3 standard groups were treated with different doses of Diclofenac (Standard drug): 5 mg/kg, 10 mg/kg, 15 mg/kg body weight, respectively and 3 test groups were treated with different doses of Theophylline (Test drug): 5 mg/kg , 10 mg/kg and 15 mg/kg, respectively. The anti-inflammatory property was assessed by plethysmograph.Results: Theophylline demonstrated a significant anti-inflammatory property at different dose levels when compared to controls (p > 0.05). However this anti-inflammatory activity was less as compared to standard drug.Conclusions: Theophylline exhibited a dose dependent anti-inflammatory activity in a carrageenan model of inflammation
Facile preparation of agarose-chitosan hybrid materials and nanocomposite ionogels using an ionic liquid via dissolution, regeneration and sol-gel transition
We report simultaneous dissolution of agarose (AG) and chitosan (CH) in
varying proportions in an ionic liquid (IL), 1-butyl-3-methylimidazolium
chloride [C4mim][Cl]. Composite materials were constructed from AG-CH-IL
solutions using the antisolvent methanol, and IL was recovered from the
solutions. Composite materials could be uniformly decorated with silver oxide
(Ag2O) nanoparticles (Ag NPs) to form nanocomposites in a single step by in
situ synthesis of Ag NPs in AG-CH-IL sols, wherein the biopolymer moiety acted
as both reducing and stabilizing agent. Cooling of Ag NPs-AG-CH-IL sols to room
temperature resulted in high conductivity and high mechanical strength
nanocomposite ionogels. The structure, stability and physiochemical properties
of composite materials and nanocomposites were characterized by several
analytical techniques, such as Fourier transform infrared (FTIR), CD
spectroscopy, differential scanning colorimetric (DSC), thermogravimetric
analysis (TGA), gel permeation chromatography (GPC), and scanning electron
micrography (SEM). The result shows that composite materials have good thermal
and conformational stability, compatibility and strong hydrogen bonding
interactions between AG-CH complexes. Decoration of Ag NPs in composites and
ionogels was confirmed by UV-Vis spectroscopy, SEM, TEM, EDAX and XRD. The
mechanical and conducting properties of composite ionogels have been
characterized by rheology and current-voltage measurements. Since Ag NPs show
good antimicrobial activity, Ag NPs -AG-CH composite materials have the
potential to be used in biotechnology and biomedical applications whereas
nanocomposite ionogels will be suitable as precursors for applications such as
quasi-solid dye sensitized solar cells, actuators, sensors or electrochromic
displays
A frictional Cosserat model for the flow of granular materials through a vertical channel
A rigid-plastic Cosserat model has been used to study dense, fully developed
flow of granular materials through a vertical channel. Frictional models based
on the classical continuum do not predict the occurrence of shear layers, at
variance with experimental observations. This feature has been attributed to
the absence of a material length scale in their constitutive equations. The
present model incorporates such a material length scale by treating the
granular material as a Cosserat continuum. Thus localised couple stresses exist
and the stress tensor is asymmetric. The velocity profiles predicted by the
model are in close agreement with available experimental data. The predicted
dependence of the shear layer thickness on the width of the channel is in
reasonable agreement with data. In the limit of the ratio of the particle
diameter to the half-width of the channel being small, the model predicts that
the shear layer thickness scaled by the particle diameter grows.Comment: 17 pages, 12 PostScript figures, uses AmsLaTeX, psfrag and natbib.
Accepted for publication in Acta Mechanic
Image Segmentation for Animal Images using Finite Mixture of Pearson Type VI Distribution
Image Segmentation is one of the significant tool for analyzing images, the feature vector of the images are different for different types of images. In remote sensing, Environmental ecological systems, forest studies, conservation of rare animals, the animal images are more important. In this paper we developed and analyze an image segmentation algorithm using mixture of Pearson Type VI Distribution. The Pearsonian Type VI Distribution will characterize the image regions of animal images. The appropriateness Pearsonian Type VI distribution for the pixel intensities of image region in animal images is carried by fitting Pearsonian Type VI Distribution to set of animal images taken from Berkeley image data set. The image segmentation algorithm is developed using EM algorithm for estimating the parameters of the model and maximum likelihood for image component under Bayesian framework. For fast convergence of EM algorithm the initial estimates of the model parameters are obtained by dividing the whole image into K image regions using K-means and Hierarchical clustering algorithm and utilizing the moment method of estimates. The performance of proposed algorithm is studied by conducting an experiment with set of animal images and computing image quality metrics such as PRI, GCE and VOI. A comparative study of developed image segmentation by Gaussian Mixture model and found the proposed algorithm performed better for animal images due to asymmetrically distributed nature of pixel intensities in the image regions
Ecological monitoring of trawling grounds
The development of mechanized fishing in India is traced to point out the harmful effects of trawling by way of disturbing the ecological balance of the ecosystem, of which the fish stocks are a part. It may cause the disappearance of some demersal species from the catches as brought out poignantly in the case of a marine catfish namely, Arius tenuispinis. History of trawling has been the same all over the world showing that depletion of demersal fish stocks is not only due to excessive harvesting but also due to the damage done to the ecological balance of the trawling grounds. The need for ecological monitoring of the trawling grounds is pointed out
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