1,452 research outputs found
Epidemiological and entomological aspects of malaria in forestfringed villages of Sonitpur district, Assam
Background & objectives : Detailed epidemiological and entomological studies were undertaken inforest-fringed villages and a Tea Estate in Sonitpur, Assam to assess the malaria situation.Methods : Door-to-door active surveillance was carried out to collect blood samples. Thick and thinblood smears stained with Giemsa were used for malaria parasite detection. Mosquito collectionswere made using CDC miniature light-traps and hand catch methods from dusk-to-dawn.Results : 48% SPR, 49.1 Pf % was recorded from the study villages. Children between 10 and 14 yearswere most sufferers. Per trap night density of mosquitoes in human dwellings was 204.3 and incattlesheds — 908.7, An. minimus accounted for 20.7% of total malaria vectors.Interpretation & conclusion : The results showed high malaria risk in the study villages. High vectordensity with high parity rate, poor socio-economic conditions, lack of awareness, poor sanitation andcongenial atmosphere for mosquito proliferation are aggravating the malaria situation more complex inthe study area
A simple method for Bachmann's bundle pacing with indigenous modification of J-stylet
AbstractBackgroundPacing in the Bachmann's bundle (BB) area (upper atrial septum) appears superior to right atrial appendage or free wall stimulation for the prevention of paroxysmal atrial fibrillation in patients with atrial conduction delay. However, insertion of active fixation lead in the upper atrial septal position is difficult and time consuming with conventional stylet, inhibiting application of this pacing method in routine practice.MethodsThe technique of positioning the atrial lead in BB with hand-made stylet is presented with emphasis on electrocardiographic P-wave pattern and fluoroscopic landmarks.ResultsThe results demonstrate an acute implantation and short-term success of BB pacing of 14 patients out of 15 patients without major complications. Pacing parameters at implantation and 3 months postprocedure were noted which were within normal limits.ConclusionThese favorable initial results indicate that the positioning of active fixation atrial lead in BB with fluoroscopic landmarks is feasible and reproducible with a simple technique
Photon sensitivity of superheated drop at room temperature
It has been reported so far that superheated drop detector made of R-12 at
room temperature are sensitive to neutrons yet insensitive to photons. This
property makes its use as one of the most useful neutron dosimeter. The photon
sensitivity of R12 at room temperature when exposed to 59.54kev photons
obtained from radioactive Am has been noted for the first time in our
laboratory. This discovery is important nt only from the point of view of basic
science but more important to the users of R12 in neutron dosimetry to take
note of this in assessing the neutron dose correctly.Comment: 3pages, 1 fig. Nuclear Instruments and Method A, 2000, (accepted
Spin symmetry breaking in bilayer quantum Hall systems
Based on the construction of generalized Halperin wave functions, we predict
the possible existence of a large class of broken spin symmetry states in
bilayer quantum Hall structures, generalizing the recently suggested canted
antiferromgnetic phase to many fractional fillings. We develop the appropriate
Chern-Simons theory, and establish explicitly that the low-lying neutral
excitation is a Goldstone mode and that the charged excitations are bimerons
with continuously tunable (through the canted antiferromagnetic order
parameter) electric charge on the individual merons.Comment: 4 page
Energetics of resting metabolism in an Indian major carp (Catla catla Ham.)
Resting metabolism in Indian major carp, Catla catla Ham. fingerlings were investigated. For this purpose a water recirculatory system in the laboratory was used. The metabolic energy losses were determined by the indirect method of oxygen consumption by the fish and were then multiplied by an oxycalorific coefficient (Q-ox). Five metabolism chambers in the experimental system were used where there were two same treatment runs in quadruplicate of mean total weight of fish fingerlings of 109.5, 110.4, 112.8 and 111.6g/chamber. The water temperature in the system was 28±0.5°C. The mean metabolic rate in the replicates showed no significant variation (p>0.05) and was found to be 151.66, 153.91, 150.25, 152.74 mgO-2/kg/h respectively. This showed an equivalent energy loss 5.40, 5.52, 5.51 and 5.56 KJ/chamber/day (35.60, 35.92, 36.67 and 36.40 KJ/kg/day) respectively. Energetics of resting metabolism in an Indian major carp (Catla catla Ham.
Superheated drop as a neutron spectrometer
Superheated drops are known to vaporise when exposed to energetic nuclear
radiation since the discovery of bubble chamber. As the degree of superheat
increases in a given liquid, less and less energetic neutrons are required to
cause nucleation. This property of superheated liquids are being utilised to
develope the neutron spectromer. A new principle of neutron spectrometry using
Superheated liquid are developed and the developed principle has been tested by
Am-Be neutron source.Comment: 9 pages, 8 figures. accepted in Nucl.Instru.MethA,200
Photoelectron Spectra Of Amorphous Sixhy Alloy Films: The Effect Of Microstructure On The Si-2p Level Shift
Depending on the deposition conditions, amorphous SixH y alloy films prepared by planar rf reactive magnetron sputtering exhibit one of three types of microstructure: (i) type A with no discernible microstructural features down to the 20-Ă… level and with a smooth uniform density; (ii) type B consisting of high-density regions of 50-200-Ă… lateral dimensions separated by a low-density network; and (iii) a two-level (type C) microstructure consisting of 300-500-Ă… dimensions columns separated by a pronounced low-density network. The columns, in turn, are composed of 50-200-Ă… dimension high-density regions interspersed with low-density network. The Si-2p level in these alloy films, determined by x-ray photoelectron spectroscopy, is observed to be strongly influenced by the microstructure of the film. A shift in the Si-2p level, systematically varying with the hydrogen concentration, is observed in alloy films with type B and type C microstructures. No shift is observed, irrespective of the hydrogen concentration, in alloy films with type A microstructure. The photoelectron spectra are examined in the light of the vibrational spectra of the films as measured by Fourier transform infrared techniques. The dependence of the Si-2p level shift on the microstructure and the variation with hydrogen concentration are explained qualitatively in terms of the differences in the silicon-hydrogen bonding in amorphous SixHy films with dissimilar microstructures.6072530253
A one-dimensional model for the growth of CdTe quantum dots on Si substrates
Recent experiments involving CdTe films grown on Si(111) substrates by hot
wall epitaxy revealed features not previously observed [S. O. Ferreira
\textit{et al.}, J. Appl. Phys. \textbf{93}, 1195 (2003)]. This system, which
follows the Volmer-Weber growth mode with nucleation of isolated 3D islands for
less than one monolayer of evaporated material, was described by a peculiar
behavior of the quantum dot (QD) size distributions. In this work, we proposed
a kinetic deposition model to reproduce these new features. The model, which
includes thermally activated diffusion and evaporation of CdTe, qualitatively
reproduced the experimental QD size distributions. Moreover, the model predicts
a transition from Stranski-Krastanow growth mode at lower temperatures to
Volmer-Weber growth mode at higher ones characterized through the QD width
distributions.Comment: to appear in Physics Letters
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