Recent epidemiological status of malaria in Calcutta Municipal Corporation area, West Bengal

In Calcutta, Plasmodium falciparum cases and death due to malaria show remarkably increasing trend since 1990. The incidence of P. falciparum malaria has increased more than eleven folds in 1996 in comparison to 1990, with 0, 0, 0, 3, 7, 52 and 17 deaths in 1990, 1991, 1992, 1993, 1994, 1995 and 1996 respectively. Situation is more serious than what it is projected in official records as annual blood examination rate (ABER) in Calcutta Municipal area is poor, varying from 1.5 to 3.9 in 1993 and 1996 respectively. This is further evident from the fact that in a study area in 19 months (January 1995 to July 1996) the slide positivity rate (SPR) was 47.94% on an average 28.72% suffer from P. falciparum infection (as low as 0.5% in June 1996 and as high as 71.5% in November 1996). For the first time resistance of P. falciparum to chloroquine has been noted at RII and RIII level. The response of the same parasite strain to sulfa-pyrimethamine combination drug is very much promising. Fresh infection is occurring in all the months of the year and the favourable period is from July to November 1995 that is corroborating with Container index and Breteau index related to the vector mosquito Anopheles. Susceptibility status of An. stephensi indicates that the mosquito species has acquired resistance to DDT, BHC, propoxure and malathion but is still susceptible to fenthion and deltamethrin.     

High spectral purity microwave oscillator: design using conventional air-dielectric cavity

We report exceptionally low PM noise levels from a microwave oscillator that uses a conventional air-dielectric cavity resonator as a frequency discriminator. Our approach is to increase the discriminator's intrinsic signal-to-noise ratio by use of a high-power carrier signal to interrogate an optimally coupled cavity, while the high-level of the carrier is suppressed before the phase detector. We developed and tested an accurate model of the expected PM noise that indicates, among other things, that a conventional air-dielectric resonator of moderate Q will exhibit less discriminator noise in this approach than do more esoteric and expensive dielectric resonators tuned to a high-order, high-Q mode and driven at the dielectric's optimum     

Biomass yield and energy analysis of soybean production in relation to fertilizer-NPK and organic manure

The study attempts to quantify the root biomass and density, nodulation, crop biomass and grain yield of soybean, to analyze crop growth and energy (renewable and non-renewable) inputs in relation to fertilizer-NPK and organic manure. Observations were recorded from soybean grown with no fertilizer, NPK and NPK + FYM (farmyard manure). The root biomass (BM_root) increased significantly with NPK + FYM compared to NPK and control. The trend of BM_root was best fitted with a third order polynomial. Root length density was higher in NPK + FYM. Biomass of stem, petiole and leaf were significantly greater in NPK + FYM than other treatments, relative contribution to total biomass at physiological maturity were stem 29%, petiole 9%, leaf 17% and pod 46%; quadratic regression models best represented the stem, petiole and leaf biomass data. A maximum LAI of 4.88, total biomass of 633 g m^?2 at maturity, CGR of 18.4 g m^?2 d^?1 were recorded in NPK + FYM. Grain yields increased by 72.5 and 98.5%, and stover yields by 56.0 and 94.8% in NPK and NPK + FYM, respectively over control. Though the total energy input in NPK + FYM was greater than those in NPK and control, the share of renewable energy was much higher with greater net energy output and non-renewable energy productivity in NPK + FYM than NPK. The use efficiency of non-renewable energy was also higher in NPF + FYM. Thus, a combination of NPK-fertilizer and organic manure (FYM) could be the viable nutrient management option for soybean production.     

Pump current modulated charge pump PLL

The performance of a charge pump PLL (CP-PLL) is strongly influenced by the pump current magnitude in the pump ON interval. An examination is presented of the effect of linearly increasing pump current on the transient response of a CP-PLL. It has been observed that the process of pump current `modulation' may be used to enhance the transient behaviour of the CP-PLL     

Optimal Natural Convection Heat Transfer Improvement by Combining Periodic Heating Temperature,Cavity Inclination,and Nanofluid

Natural convection within a square inclined cavity filled with Al₂O₃–water nanofluid is investigated numerically. The temperature of the cooled surface is maintained constant, while that of the opposite surface (heating temperature) is varied sinusoidally in time. The remaining walls are considered adiabatic. The parameters governing the problem are the amplitude and the period of the variable temperature, the Rayleigh number, the inclination of the cavity, and the solid volume fraction. A substantial enhancement of heat transfer is obtained by combining the beneficial effects of the variable heating temperature (via its period and amplitude), the inclination of the cavity, and the nanoparticles fraction. In comparison with the constant heating conditions, it is found that both the variable heating temperature and the inclination of the cavity may lead to drastic changes in the flow structure and the corresponding heat transfer. The resonance phenomenon, observed for critical periods of the exciting temperature, is amplified by adding Al₂O₃ nanoparticles to the base fluid.     

滴定法测定饲料添加剂中硫酸亚铁含量的不确定度探讨

依据HG2935—2000饲料级一硫酸亚铁标准规定,对重铬酸钾滴定法测定硫酸亚铁含量的不确定进行了评定,建立了测量过程中各个分量的数学模型,并估算了各不确定度分量对总不确定度的影响。结果表明,在置信概率水平为95％时,硫酸亚铁含量测量结果报告为x=（80．34±0．48）％,k=2。该方法适用于硫酸亚铁含量的不确定评定,其中影响硫酸亚铁含量的不确定度主要来源是滴定体积所引入。