313 research outputs found
Fluid melt inclusion studies on different minerals of pegmatites intruding in Nelore Schist Belt, Andhra-Pradesh, India
Generation of Groundwater Quality Index Map: A Case Study
Reliance on groundwater has been rapidly increasing, especially in the arid and semiarid regions, resulting in its overexploitation leading to deterioration of quality. Kurmapalli Vagu basin of Andhra Pradesh, a semi-critical region with respect to the stage of groundwater development is a good example. Its monitoring and assessment is imperative for devising preventive measures against health hazards. Groundwater samples from twenty five locations were collected and analyzed for various physico-chemical parameters in terms of Water Quality Index (WQI) to determine its suitability for drinking purposes. Seven locations were found to have WQI value within the limits. High values of WQI were mostly due to high content of Fluorides. WQI Contour map was generated to study spatial distribution of quality of groundwater. Suitable remedial measures and groundwater augmenting structures are proposed in the study area to improve the quality of groundwater. Keywords: Groundwater, WQI, Fluorosis, Groundwater augmenting structures
Impact of HIV Infection on Radiographic Features in Patients with Pulmonary Tuberculosis
Background. There is insufficient data on the radiographic presentation of tuberculosis in human immunodeficiency virus
(HIV) infected patients from India.
Methods. We examined the chest radiographs of 181 patients including 82 HIV positives with newly diagnosed sputum
culture positive pulmonary tuberculosis before and after the completion of anti-tuberculosis treatment (ATT). Patients with
smear/culture positive pulmonary tuberculosis were treated with Revised National Tuberculosis Control Programme
(RNTCP) Cat-I regimen (2EHRZ3/4HR3). An independent assessor blinded to HIV and clinical status of patients read the
radiographs.
Results. At presentation, HIV seropositive patients were significantly more likely to have normal chest radiographs (14.2%
vs 0), miliary tuberculosis (10.7% vs 1%) and pleural effusion (16.6% vs 3%), and less likely to have cavitation (17.8% vs
39.4%) as compared to HIV negative patients. At the end of treatment, HIV positive patients were more likely to have normal
radiographs (42.8% vs 1.2%), and less likely to have fibrosis (17.8% vs 42.5%).
Conclusions. The radiographic presentation of pulmonary tuberculosis in HIV-infected patients is atypical with less
cavitation, and more dissemination. On completion of ATT, patients with HIV have less radiographic sequelae in the form
of fibrosis. These features may be due to the reduced inflammatory response that patients with HIV infection may be able
to mount
Safety evaluation of chromium picolinate in experimental rats
Background: Chromium, an essential trace mineral plays an important role in the metabolism of carbohydrate, fat and proteins. Chromium picolinate (Cr.Pic) is used in alternative medicine to treat chromium deficiency. Though Cr.Pic is increasingly used to treat diabetes and obesity, studies on its safety profile is limited.Methods: Acute toxicity study was conducted by oral administration of Cr.Pic (2000 mg/kg body weight). The animals were maintained another 14 days with once a day observation. For sub-chronic studies, test groups were treated with Cr.Pic 10 mg/kg/day for 90 days. Tests for hepatic and renal function were conducted. Effect of Cr.Pic on behavioural changes and motor co-ordination was done on every week. Histopathological studies were conducted on day 90 at the end of the experiment.Results: Acute toxicity study of Cr.Pic showed no signs of toxicity and mortality. Absence of any behavioural alteration or mortality during the period of 14 days indicates that Cr.Pic has no latent effect. Similar results were obtained with sub-chronic studies suggesting safety of Cr.Pic. Cr.Pic treated groups showed no changes in learning and motor co-ordination compared to the untreated group. No gross histopathological changes were seen in any group indicating safety of Cr.Pic.Conclusions: The present study conferred safety profile of Cr.Pic from normal results obtained in hepatic function, renal function, behavioural and histopathological studies, suggesting its safety
Effects of Next-Nearest-Neighbor Hopping on the Hole Motion in an Antiferromagnetic Background
In this paper we study the effect of next-nearest-neighbor hopping on the
dynamics of a single hole in an antiferromagnetic (N\'{e}el) background. In the
framework of large dimensions the Green function of a hole can be obtained
exactly. The exact density of states of a hole is thus calculated in large
dimensions and on a Bethe lattice with large coordination number. We suggest a
physically motivated generalization to finite dimensions (e.g., 2 and 3). In
we present also the momentum dependent spectral function. With varying
degree, depending on the underlying lattice involved, the discrete spectrum for
holes is replaced by a continuum background and a few resonances at the low
energy end. The latter are the remanents of the bound states of the
model. Their behavior is still largely governed by the parameters and .
The continuum excitations are more sensitive to the energy scales and
.Comment: To appear in Phys. Rev. B, Revtex, 23 pages, 10 figures available on
request from [email protected]
Air-Abrasion in Dentistry: A Short Review of the Materials and Performance Parameters
The selection of abrasive material and parameters of the Air-Abrasion device for a particular application is a crucial detail. However, there are no standard recommendations or manuals for choosing these details; the operator must depend on his experience and knowledge of the procedure to select the best possible material and set of parameters. This short review attempts to identify some of the effects that the selection of material and parameters could have on the performance of the Air-Abrasion procedure for a particular application. The material and parameter data are collected from various studies and categorized according to the most popular materials in use right now. These studies are then analyzed to arrive at some inferences on the performance of Air-Abrasion materials and parameters. This review arrives at a few conclusions on the effectiveness of a material and parameter set, and that there is potential for developments in the area of standardizing parameter selection; also, there is scope for further studies on Bio-Active Glass as an alternative to the materials currently used in Air-Abrasion
Deep Rooting In-Situ Expansion of mtDNA Haplogroup R8 in South Asia
The phylogeny of the indigenous Indian-specific mitochondrial DNA (mtDNA) haplogroups have been determined and refined in previous reports. Similar to mtDNA superhaplogroups M and N, a profusion of reports are also available for superhaplogroup R. However, there is a dearth of information on South Asian subhaplogroups in particular, including R8. Therefore, we ought to access the genealogy and pre-historic expansion of haplogroup R8 which is considered one of the autochthonous lineages of South Asia.Upon screening the mtDNA of 5,836 individuals belonging to 104 distinct ethnic populations of the Indian subcontinent, we found 54 individuals with the HVS-I motif that defines the R8 haplogroup. Complete mtDNA sequencing of these 54 individuals revealed two deep-rooted subclades: R8a and R8b. Furthermore, these subclades split into several fine subclades. An isofrequency contour map detected the highest frequency of R8 in the state of Orissa. Spearman's rank correlation analysis suggests significant correlation of R8 occurrence with geography.The coalescent age of newly-characterized subclades of R8, R8a (15.4+/-7.2 Kya) and R8b (25.7+/-10.2 Kya) indicates that the initial maternal colonization of this haplogroup occurred during the middle and upper Paleolithic period, roughly around 40 to 45 Kya. These results signify that the southern part of Orissa currently inhabited by Munda speakers is likely the origin of these autochthonous maternal deep-rooted haplogroups. Our high-resolution study on the genesis of R8 haplogroup provides ample evidence of its deep-rooted ancestry among the Orissa (Austro-Asiatic) tribes
Temperature-Dependent Infrared Reflectivity Studies of Multiferroic TbMnO_{3}: Evidence for Spin-Phonon Coupling
We have measured near normal incidence far infrared (FIR) reflectivity
spectra of a single crystal of TbMnO3 from 10K to 300K in the spectral range of
50 cm to 700 cm. Fifteen transverse optic (TO) and longitudinal
optic (LO) modes are identified in the imaginary part of the dielectric
function () and energy loss function
Im(-1/()), respectively. Some of the observed phonon modes
show anomalous softening below the magnetic transition temperature T (~
46K). We attribute this anomalous softening to the spin-phonon coupling caused
by phonon modulation of the super-exchange integral between the Mn
spins. The effective charge of oxygen (Z) calculated using the measured
LO-TO splitting increases below T.Comment: 16 pages, 6 figures, 1 tabl
Daksha: On Alert for High Energy Transients
We present Daksha, a proposed high energy transients mission for the study of
electromagnetic counterparts of gravitational wave sources, and gamma ray
bursts. Daksha will comprise of two satellites in low earth equatorial orbits,
on opposite sides of earth. Each satellite will carry three types of detectors
to cover the entire sky in an energy range from 1 keV to >1 MeV. Any transients
detected on-board will be announced publicly within minutes of discovery. All
photon data will be downloaded in ground station passes to obtain source
positions, spectra, and light curves. In addition, Daksha will address a wide
range of science cases including monitoring X-ray pulsars, studies of
magnetars, solar flares, searches for fast radio burst counterparts, routine
monitoring of bright persistent high energy sources, terrestrial gamma-ray
flashes, and probing primordial black hole abundances through lensing. In this
paper, we discuss the technical capabilities of Daksha, while the detailed
science case is discussed in a separate paper.Comment: 9 pages, 3 figures, 1 table. Additional information about the mission
is available at https://www.dakshasat.in
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