831 research outputs found
Modeling charge transport in Swept Charge Devices for X-ray spectroscopy
We present the formulation of an analytical model which simulates charge
transport in Swept Charge Devices (SCDs) to understand the nature of the
spectral redistribution function (SRF). We attempt to construct the
energy-dependent and position dependent SRF by modeling the photon interaction,
charge cloud generation and various loss mechanisms viz., recombination,
partial charge collection and split events. The model will help in optimizing
event selection, maximize event recovery and improve spectral modeling for
Chandrayaan-2 (slated for launch in 2014). A proto-type physical model is
developed and the algorithm along with its results are discussed in this paper.Comment: 9 pages, 7 figures, Proc. SPIE 8453, High Energy, Optical, and
Infrared Detectors for Astronomy
An improved method for the synthesis of cyclopropyl ketoesters
A simple and versatile method for the synthesis of cyclopropyl ketoesters starting from chalcones and ethyl cyanoacetate in benzene using sodium powder as base is described
Fibre optic sensor to detect heavy metal pollutants in water environments.
Heavy metal ion pollution emerges as a potential threat to humankind and the ecosystem due to their increased spreading into the environment. Detection of highly toxic heavy metal ions requires rapid, simple, sensitive and selective detection methods in water environments. Optical fibre sensors facilitate the remote, continuous and in-situ detection due to their inherent properties. Herein, we report a fibre optic sensor based on evanescent wave absorption to detect heavy metal ions in water environments. Fibre optic sensor has been developed by coating dithizone on the surface of an optical fibre. Selectivity of the mercury, copper and chromium ions using dithizone has been illustrated using spectroscopy based detection approach. Effect of pH on the sensor has been investigated. The possibility of simultaneous multi-ion detection has been investigated. Copper ions concentrations in water has been detected using the developed fibre optic sensor
Value of dual testing for identifying tuberculous infection
Setting: A rural community in Chingleput district in Tamil Nadu state in south India.
Objective: To determine the value of dual testing with PPD-S and PPD-B for
identifying subjects with a tuberculous infection.
Design: About 240,000 subjects in rural south India, all of whom were tested
initially with PPD-S and PPD-B, were followed up for 15 years, mainly by total
population survey once in every 212
years. The incidence of culture-positive
tuberculosis was estimated using life-table technique.
Results: Among 17,530 subjects with an intermediate reaction (8–11 mm) to PPD-S
at intake, 285 with an induration to PPD-S exceeding the induration to PPD-B by at
least 2 mm, had a significantly higher incidence of culture-positive tuberculosis than
the remaining (154 and 93 per 100,000), and similarly 481 who had an induration of
o10mm to PPD-B compared to those with X10mm (131 and 93 per 100,000). These
subjects may be regarded as having a tuberculous infection.
Infection with non-tuberculous mycobacteria conferred protection of about 30%
against the development of tuberculosis over a 15-year period.
Conclusion: In subjects with an intermediate reaction (8–11 mm) to PPD-S, dual
testing with PPD-B enabled identification of those with a tuberculous infection. Most
of the reactions were due to non-tuberculous mycobacteria
Establishment of High-Efficiency Agrobacterium-Mediated Transformation of Callus Derived from \u3cem\u3eSehima nervosum\u3c/em\u3e, an Important Range Grass Species
Sehima nervosum is one of the important rangeland grass in India, It is commonly known as Saen grass in India, white grass in Australia, and has also been reported from the Central East Africa and Sudan. It is a good forage grass and maybe utilized for grazing as well as for hay preparation. It is a perennial grass, prefers hot and dry climate and survive even in limited rainfalls. As this natural grass is found inherently rich in precursors for several industrially important biomolecules, fractionation of these precursors seems to be a promising endeavour. Production of nutraceuticals (prebiotic xylo-oligosaccharides) from the lignocellulosic biomass of this grass is promising, as this grass does not compete with food crops, and is comparatively less expensive than conventional agricultural food-stocks. However, germplasm of this grass has narrow genetic variability. Being largely apomictic in reproduction, generation of variability through hybridization approaches have been limited. Utilization of biotechnological tools is one of the potential ways for introducing variability and transfer of desirable traits. The development of an efficient genetic transformation procedure for Sehima could facilitate physiological and molecular biology studies as well as the production of transgenic cultivars for higher productivity and quality.
To the best of our knowledge there are no reports on in vitro callus induction, regeneration and transformation in Sehima. Herein, for the first time, efficient in vitro callus induction from mature seed explant and transformation efficiency in Sehima is reported. Here we standardized a reproducible, rapid and efficient Agrobacterium mediated transformation using Agrobacterium strain EHA105 harbouring binary vector pCAMBIA 1305
The Role of Diet in the Treatment of Pulmonary Tuberculosis: An Evaluation in a Controlled Chemotherapy Study in Home and Sanatorium Patients in South India
Before the advent of antituberculosis chemotherapy, a diet rich in calories, proteins,
fats, minerals and vitamins was generally considered to be an important, if not essential,
factor in the treatment of tuberculosis. The introduction of specific antituberculosis drugs,
however, has so radically altered the management of the disease that the role of diet has to
be reconsidered in the light of the recent advances in treatment. An evaluation of the influence
of diet in the treatment of pulmonary tuberculosis with isoniazid plus p-aminosalicylic acid
was recently undertaken by the Tuberculosis Chemotherapy Centre, Madras, in the course
of a controlled comparison of home and sanatorium chemotherapy for tuberculous patients
from a poverty-stricken community in Madras City. Despite the fact that during the year of
treatment the home patients subsisted on a markedly poorer diet, were physically more active
and, on the average, gained less weight than the sanatorium patients, the overall response to
treatment in the home series closely approached that in the sanatorium series, although
there was a tendency for tubercle bacilli to disappear earlier in the latter. Direct evidence
has been presented that none of the dietary factors studied (calories, carbohydrates, total
and animal proteins, fats, minerals and vitamins) appears to influence the attainment of
quiescent disease among tuberculous patients treated for one year with an effective
combination of antimicrobial drugs, and that initial chemotherapy of patients at home can
be successful even if the dietary intake is low throughout the period of treatment
Trends and the pole tide in Indian tidegauge records
This paper studies tidegauge records of stations on the Indian coastline. An analysis of trends did not reveal a monotonie trend. Trends were seen for limited periods at only five of the eight stations on the Indian coast. A spectral analysis of annual records produced evidence of long period cycles with shorter cycles riding on them. The shorter cycles had a period of 5.0 years. The spectra of monthly records revealed evidence of a pole tide and an annual cycle. The amplitude of the pole tide was estimated to be around 7.5 mm. This was larger than the equilibrium tide. A spectral analysis of monthly rainfall at Bombay, a station on the Indian west coast, also showed a 13.9 month cycle and a (3,1,0) autoregressive model. But the coherence between monthly rainfall and relative sealevel fluctuations was low
A novel system to obtain addresses of out-patients-assessent in routine clinic practice in Madras
A novel method of obtaining accurate home addresses from out-patients was
introduced as a routine procedure in 6 chest clinics of Madras City, following highly
satisfactory results under study conditions. In this method, the patient is given
a card (the address card), and asked to get his exact address entered on it by any
knowledgeable person of his choice such as a landlord or neighbour. An assessment
of the system was undertaken after it had been in operation for about 8 months.
A complete and legible address was available for 82 % of 3956 patients, the range in
the 6 clinics being 74 % to 91 %. The main causes for failure were : not giving address
card to patient (7 %), patient not reattending the clinic (6 %), and patient reattending
but not returning the address card (3%). Corrective measures have now been
introduced, and a re-assessment will be undertaken in due course
- …