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1.
Hydroxyprogesterone caproate is one of the most effective and widely used drugs for the treatment of uterine bleeding and threatened miscarriage in women. Hydroxyprogesterone caproate was administered to pregnant rats in order to assess the effect of intraperitoneal exposure to supranormal levels of hydroxyprogesterone caproate on the male reproductive potential in the first generation. The cauda epididymal sperm count and motility decreased significantly in rats exposed to hydroxyprogesterone caproate during embryonic development, when compared with control rats. The levels of serum testosterone decreased with an increase in follicle stimulating hormone and luteinizing hormone in adult rats exposed to hydroxyprogesterone caproate during the embryonic stage. It was suggested that the impairment of male reproductive performance could be mediated through the inhibition of testosterone production. 相似文献
2.
P. Noorunnisa Khanam H. P. S. Abdul Khalil M. Jawaid G. Ramachandra Reddy C. Surya Narayana S. Venkata Naidu 《Journal of Polymers and the Environment》2010,18(4):727-733
The variation of mechanical properties such as tensile and flexural properties of randomly oriented unsaturated polyester
based sisal/carbon fibre reinforced hybrid composites with different fibre weight ratios have been studied. The chemical resistance
test of these hybrid composites to various solvents, acids and alkalies were studied. The effect of NaOH treatment of sisal
fibres on the tensile, flexural and chemical resistance properties of these sisal/carbon hybrid composites has also been studied.
The hybrid composites showed an increase in tensile and flexural properties with increase in the carbon fibre loading. The
tensile properties and flexural properties of these hybrid composites have been found to be higher than that of the matrix.
Significant improvement in tensile properties and flexural properties of the sisal/carbon hybrid composites has been observed
by alkali treatment. The chemical resistance test results showed that these untreated and alkali treated hybrid composites
are résistance to all chemicals except carbon tetra chloride. Hand lay-up technique was used for making the composites and
tests are carried out by using ASTM methods. 相似文献
3.
N. Mithil Kumar K. Varaprasad G. Ramachandra Reddy G. Siva Mohan Reddy Y. Sivabharathi G. Venkata Subba Reddy S. Venkata Naidu 《Journal of Polymers and the Environment》2011,19(1):225-229
Synthesis and characterization of novel biodegradable, water soluble and optically active DL-malic acid (DMA) and citric acid
(CA) copolymers were studied for possible use as antibacterial agents. The copolymers were synthesized by direct bulk melt
condensation in the absence of a catalyst above 150 °C. Characterization of obtained copolymers was carried out with the help
of infrared absorption spectra, differential scanning calorimetry and thermo gravimetric analysis. The antibacterial activity
of copolymers against bacteria was investigated. The results obtained shows the above copolymers possess a broad wound dressing
activity against different types of bacteria and may be useful as antibacterial agents. 相似文献
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Pregnant Wistar strain albino rats were administered hydroxyprogesterone and the steroidogenic potential of the testis was analysed in the next generation adult male rats. In utero exposure to supranormal levels (10 mg/kg body weight or 25 mg/kg body weight) of hydroxyprogesterone decreased the activity levels of marker steroidogenic enzymes (3beta-hydroxysteroid dehydrogenase and 17beta-hydroxysteroid dehydrogenase) of adult (mature) rat testis. Hydroxyprogesterone mediation in the suppression of rat testicular steroidogenesis is suggested, which can be correlated to the observed decrease in male reproductive potential in mammals exposed to female hormones during embryonic development. 相似文献
6.
P. Noorunnisa Khanam H. P. S. Abdul Khalil G. Ramachandra Reddy S. Venkata Naidu 《Journal of Polymers and the Environment》2011,19(1):115-119
In this study, effect of fibre surface treatment on tensile, flexural and chemical resistance properties were studied for
sisal fibre reinforced composites. Natural ligno cellulosic sisal fibre reinforced composites were prepared by different surface
treatments by hand lay-up method. Fibre surface treatments were carried out to produce good interface between the fibre and
the matrix to improve the mechanical properties. Fibre surface treatments were done by boiled the sisal fibres in different
% of NaOH and treated the fibres in different % of NaOH, treated in acetic acid and methanol. Unsaturated polyester resin
was used as the matrix for preparing the composites. For comparison, these properties for untreated sisal fibre reinforced
composites were also studied. From the results it was observed that 18% aqueous NaOH boiled sisal fibre reinforced composites
have higher tensile, flexural properties than other composites. Untreated sisal fibre composites show lower properties than
treated composites. Chemical resistance properties indicate that all sisal fibre reinforced composites are resistance to all
chemicals except carbon tetra chloride. The tests are carried out as per the ASTM standards. 相似文献
7.
Ramachandra Jayashree Tenkila Veerappa Subba Reddy Nandanavana Udupi Dinesh Acharya 《Environmental science and pollution research international》2022,29(28):41953-41970
Environmental Science and Pollution Research - Accurate estimation of reference evapotranspiration (ET0) is an essential requirement for water resource management and scheduling agricultural... 相似文献
8.
T.V. Ramachandra 《Atmospheric environment (Oxford, England : 1994)》2009,43(34):5510-5517
A decentralized emission inventories are prepared for road transport sector of India in order to design and implement suitable technologies and policies for appropriate mitigation measures. Globalization and liberalization policies of the government in 90's have increased the number of road vehicles nearly 92.6% from 1980–1981 to 2003–2004. These vehicles mainly consume non-renewable fossil fuels, and are a major contributor of green house gases, particularly CO2 emission. This paper focuses on the statewise road transport emissions (CO2, CH4, CO, NOx, N2O, SO2, PM and HC), using region specific mass emission factors for each type of vehicles. The country level emissions (CO2, CH4, CO, NOx, N2O, SO2 and NMVOC) are calculated for railways, shipping and airway, based on fuel types. In India, transport sector emits an estimated 258.10 Tg of CO2, of which 94.5% was contributed by road transport (2003–2004). Among all the states and Union Territories, Maharashtra's contribution is the largest, 28.85 Tg (11.8%) of CO2, followed by Tamil Nadu 26.41 Tg (10.8%), Gujarat 23.31 Tg (9.6%), Uttar Pradesh 17.42 Tg (7.1%), Rajasthan 15.17 Tg (6.22%) and, Karnataka 15.09 Tg (6.19%). These six states account for 51.8% of the CO2 emissions from road transport. 相似文献
9.
Yuanqing Wang Liu Yang Sunsheng Han Chao Li T. V. Ramachandra 《Mitigation and Adaptation Strategies for Global Change》2017,22(7):993-1019
China and India together have more than one third of the world population and are two emerging economic giants of the developing world now experiencing rapid economic growth, urbanization, and motorization. The urban transportation sector is a major source of carbon dioxide (CO2) emissions in China and India. The goal of this study is to analyze the characteristics and factors of CO2 emissions produced by commuters in Chinese and Indian cities and thus to identify strategies for reducing transportation CO2 emissions and mitigating global climate change. Xi’an in China and Bangalore in India were chosen as two case study cities for their representativeness of major cities in China and India. The trends of CO2 emissions produced by major traffic modes (electric motors, buses, and cars) in major cities of China and India were predicted and analyzed. The spatial distributions of CO2 emissions produced by commuters in both cities were assessed using spatial analysis module in ArcGIS (Geographic Information System) software. Tobit models were then developed to investigate the impact factors of the emissions. The study has several findings. Firstly, in both cities, the increase of vehicle occupancy could reduce commuting CO2 emissions by 20 to 50 % or conversely, if vehicle occupancy reduces, an increase by 33.33 to 66.67 %. It is estimated that, with the current increasing speed of CO2 emissions in Xi’an, the total CO2 emissions from electric motors, buses, and cars in major cities of China and India will be increased from 135?×?106 t in 2012 to 961?×?106 t in 2030, accounting for 0.37 to 2.67 % of the total global CO2 emissions of 2013, which is significant for global climate change. Secondly, households and individuals in the outer areas of both cities produce higher emissions than those in the inner areas. Thirdly, the lower emissions in Xi’an are due to the higher density and more compact urban pattern, shorter commuting distances, higher transit shares, and more clean energy vehicles. The more dispersed and extensive urban sprawl and the prevalence of two-wheeler motorbikes (two-wheeler motorbike is abbreviated as “two-wheeler” in the following sections) fueled by gasoline cause higher emissions in Bangalore. Fourthly, car availability, higher household income, living outside the 2nd or Outer Ring Road, distance from the bus stop, and working in the foreign companies in Bangalore are significant and positive factors of commuting CO2 emissions. Fifthly, “70-20” and “50-20” (this means that generally, 20 % of commuters and households produce 70 % of total emissions in Xi’an and 20 % of commuters and households produce 50 % of total emissions in Bangalore) emission patterns exist in Xi’an and Bangalore, respectively. Several strategies have been proposed to reduce urban CO2 emissions produced by commuters and further to mitigate global climate change. Firstly, in the early stage of fast urbanization, enough monetary and land investment should be ensured to develop rail transit or rapid bus routes from outer areas to inner areas in the cities to avoid high dependency on cars, thus to implement the transit-oriented development (TOD), which is the key for Chinese and Indian cities to mitigate the impact on global climate change caused by CO2 emissions. Secondly, in Bangalore, it is necessary to improve public transit service and increase the bus stop coverage combined with car demand controls along the ring roads, in the outer areas, and in the industry areas where Indian foreign companies and the governments are located. Thirdly, Indian should put more efforts to provide alternative cleaner transport modes while China should put more efforts to reduce CO2 emissions from high emitters. 相似文献
10.
A. Ramachandra Rao Srinivasa G. Rao R. L. Kashyap 《Journal of the American Water Resources Association》1985,21(5):757-770
Stochastic models fitted to hydrologic data of different time scales are interrelated because the higher time scale data (aggregated data) are derived from those of lower time scale. Relationships between the statistical properties and parameters of models of aggregated data and of original data are examined in this paper. It is also shown that the aggregated data can be more accurately predicted by using a valid model of the original data than by using a valid model of the aggregated data. This property is particularly important in forecasting annual values because only a few annual values are usually available and the resulting forecasts are relatively inaccurate if models based only on annual data are used. The relationships and forecasting equations are developed for general aggregation time and can be used for hourly and daily, daily and monthly or monthly and yearly data. The method is illustrated by using monthly and yearly streamflow data. The results indicate that various statistical characteristics and parameters of the model of annual data can be accurately estimated by using the monthly data and forecasts of annual data by using monthly models have smaller one step ahead mean square error than those obtained by using annual data models. 相似文献