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101.
Aluminum and its salts widely used in our daily life have been reported nephrotoxic to humans and animals following prolonged exposure. Therefore, the present study was made to examine the renoprotective role of Spirulina platensis against Al3+ and AlF3 in male Swiss albino mice. Exposure to these chemicals decreased feed and water intake, and body and kidney weights. Histology of kidney and their biochemistry were also markedly altered along with that of serum biochemistry. Spirulina not only minimize toxic effects of test chemicals but also favored faster recovery of treated mice after their withdrawal.  相似文献   
102.
Selenium status in food grains of northern districts of India   总被引:2,自引:0,他引:2  
The selenium status in the food grains of the agricultural lands of northern parts of India was estimated by using the HG-AAS technique. The areas where lesser rains were received or less irrigation water was available in northern Indian states viz. Rajasthan and southern parts of the Haryana had higher selenium levels in food grains. Punjab, Himachal Pradesh and northern parts of the Haryana states had normal levels of selenium in their food grains, except for slightly lower selenium levels in a few areas that were affected by floods along the river Yamuna.  相似文献   
103.
This paper reports a regional contamination of the environment in central-east India that does not share geology or boundary with the Bengal Delta Plain. About 30,000 people residing in 30 villages and towns are directly exposed to arsenic and more than 200,000 people are "at risk." Complete geographical extent of this contamination is being established, and this newly reported contaminated area could be quite large. This paper further reports that the mechanisms involved in arsenic mobilisation are complex and the two theories of arsenic mobilisation, i.e., pyrite oxidation and oxyhydroxides reduction, do not fully explain the high levels of arsenic contamination. This paper also proposes the "oxidation-reduction theory" for arsenic mobilisation where the arsenic originates from the arsenopyrite oxidation and the arsenic thus mobilised forms the minerals and gets reduced underground in favourable Eh conditions. The stoppage of water withdrawal from the contaminated sources did not result in lowering of arsenic levels as expected according to the heavy groundwater extraction theory (pyrite oxidation theory). Cases of arsenicosis in the region are on the rise and the switchover to less contaminated water has not reversed the arsenicosis progression in the affected persons even after 2 years. Surface water of the rivers is also being contaminated because of the probable dislocation of contaminated groundwater due to the heavy rains in monsoon season, which indicates that the river water could be a major carrier of arsenic in dissolved or adsorbed forms that may be a cause of contamination of the delta plains.  相似文献   
104.
Singh SK  Yadav RP  Tiwari S  Singh A 《Chemosphere》2005,59(2):263-270
The aqueous stem bark and leaf extracts of plant Euphorbia hirta (family-Euphorbiaceae) have potent molluscicidal activity. Sub-lethal doses (40% and 80% of LC50) of aqueous stem bark and leaf extracts of this plant also significantly (P<0.05) alter the levels of total protein, total free amino acid, nucleic acids (DNA and RNA) and the activity of enzyme protease and acid and alkaline phosphatase in various tissues of the vector snail Lymnaea acuminata in time and dose dependent manner. Euphorbia hirta (family-Euphorbiaceae) commonly known as Dudhi, is a common medicinal plant of India, which is used in variety of diseases i.e. cough, asthma, colic, dysentery, genito urinary diseases.  相似文献   
105.
A time series approach using autoregressive integrated moving average (ARIMA) modeling has been used in this study to obtain maximum daily surface ozone (O3) concentration forecasts. The order of the fitted ARIMA model is found to be (1,0,1) for the surface O3 data collected at the airport in Brunei Darussalam during the period July 1998-March 1999. The model forecasts of one-day-ahead maximum O3 concentrations have been found to be reasonably close to the observed concentrations. The model performance has been evaluated on the basis of certain commonly used statistical measures. The overall model performance is found to be quite satisfactory as indicated by the values of Fractional Bias, Normalized Mean Square Error, and Mean Absolute Percentage Error as 0.025, 0.02, and 13.14% respectively.  相似文献   
106.
Measurements of temperature, salinity, dissolved oxygen, nitrogen as ammonia, nitrate and nitrite, and phosphate along with chlorophyll were carried out at three stations on the coastal waters of Cochin, south west India, at two-levels of the water column over a period of five years. The data set has been factorised using principal component analysis (PCA) for extracting linear relationships existing among a set of variables. A graphical display of the scores generated from the PCA was done by means of boxplots and biplots, which helped in the interpretation of the data. The major factors conditioning the system are related to the input of fresh water from the estuary of the Periyar river and the high organic load of the bottom sediment in the coastal area which results in a reducing environment, as reflected in the parameters of dissolved oxygen, ammoniacal-nitrogen and nitrite-nitrogen. Another factor which contributes to the variation in the system is related to the unloading activity in the port area. The present approach presents a logical way to interpret the complex data of the physico-chemical measurements.  相似文献   
107.
Thirty-six polyurethane foam disk passive air samplers (PUF-PAS) were deployed over a year during January to December, 2009 at three locations, i.e., Imphal (urban site), Thoubal (rural site) and Waithou (alpine site) of Manipur, to assess the seasonal local atmospheric emission of selected organochlorine pesticides (OCPs). The average concentration of HCHs monitored at mountain site during hot season (Mar, Apr, and May) and rainy seasons (Jun, Jul, Aug, and Sep) were 403 and 349 pg/m3, respectively. DDTs had a high concentration with 384 pg/m3 at rural site and 379 pg/m3 at urban site during hot seasons. Endosulfans and chlordane were found high in concentration during hot seasons (260 pg/m3) and low during retreating monsoon seasons (44 pg/m3) at rural site. Most of the OCPs concentrations were high during cultivation period. The OCP concentrations of rainy season were highly correlated (p < 0.01) with OCPs of hot seasons. Further, positive correlation (p < 0.05) was also obtained between cold seasons and retreating monsoon. Principal component analysis showed a significant correlation among the four seasons and distribution pattern of OCPs in air. Back trajectory analysis by using HYPSLIT model showed a long range air transport of OCPs to the present study area. Present OCP levels at Manipur is an outcome of both local emission and also movement of air mass by long range atmospheric transport.  相似文献   
108.
ABSTRACT

This case study was conducted in Himalayan watershed to understand traditional farming and socio-economic status of the people in Kumaon Himalaya, Uttarakhand, India. In spite of high literacy rate in this area, their livelihood security is reliant on traditional farming practices that include agroforestry beside forest produce. More than 85% farming is rainfed and managed in a traditional way. Land holding size owned by farmers in the area extended from 0.57 to 2.57 ha but majority of farmers (51–80%) had farms of size less than 0.50 ha. The study revealed that forests provided 73–79% of required energy from fuelwood and more than 81% fodder. Agroforestry, livestock (dairy and poultry/goat rearing) and labour employment are the major sources of income to the people in the watershed. The income of people was positively correlated with livestock rearing and traditional farming.  相似文献   
109.
110.
In the present study, depending upon the availability and cheaper cost, different carbon source were tested for the production of PHAs (Polyhydroxyalkonoates) by soil bacterium Pseudomonas aeruginosa and it was found that sugar refinery waste (cane molasses) produced the maximum PHA (biodegradable polymer) which is precursor for bio-plastic development. Urea served as potent nitrogen source over other inorganic nitrogen sources in bio-plastic synthesis. Effect of different physical parameters viz; pH, temperature and agitation speed were also studied on PHA production. Batch cultivation kinetics under optimized cultural and physical condition showed maximum cell mass and PHA concentration of 7.32?±?0.2 and 5.60?±?0.3?g/L, respectively after 54.0?h of cultivation. Sugar refinery waste (Total sugar 4%) and urea (0.8%) improved the economics of the process which exhibited a yield (YP/X) of 0.70 with productivity of 0.11?g/L/h. PHA was further characterized as PHB by using Fourier Transform Infra-red Spectroscopy (FT-IR).  相似文献   
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