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101.
Environmental Science and Pollution Research - Assessment of life history strategies of economically important small indigenous fishes (SIF) which are rich in nutritive values is essential and...  相似文献   
102.
The impacts of elevated CO(2) and temperature on microbial biomass and soil enzyme activities in four physicochemically different types of tropical rice soils (Aeric Endoaquept, Aeric Tropoaquept, Ultic Haplustalf and Udic Rhodostalf) were investigated in a laboratory incubation study. Soil samples were incubated under 400, 500 and 600 μmol mol(-1) CO(2) concentration at 25°C, 35°C and 45°C for 2 months. Elevated CO(2) significantly increased the mean microbial biomass carbon (MBC) content, across the soils, over control by 6.2%, 38.0% and 49.2% at 400, 500 and 600 μmol mol(-1) CO(2) concentration, respectively. Soil enzyme activities (fluorescein diacetate hydrolase, dehydrogenase, β-glucosidase, urease, alkaline and acid phosphatases) also increased significantly ranging from 1.3% (urease) to 53.2% (alkaline phosphatase) under high CO(2) in the soils studied. Both MBC and soil enzyme activities were further stimulated at high temperatures suggesting elevated CO(2) and high temperature interaction accelerated the general turnover of the organic C fractions of the soil and through increase in microbially mediated processes.  相似文献   
103.
Since its introduction, prenatal diagnosis of chromosomal and metabolic disorder by mid-trimester amniocentesis has relied upon the use of a mixture of fetal cells obtained from amniotic fluid. Little knowledge has been gained in the sorting of these cells for diagnosis of tissue-specific disorders. In an attempt to determine the contribution of fetal colonic mucosal cells to the overall amniocyte population, we used the colonic epithelial-specific monoclonal antibody (MC-Ab) 7E12H12, IgM isotype. Specimens of the small intestine, colon, buccal mucosa, kidney, urinary bladder, and umbilical cord were obtained from electively aborted normal fetuses of 12–28 weeks' gestation. All of these specimens were examined with 7E12H12 by the immunoperoxidase technique. The MC-Ab reacted with the colonic epithelial cells but not with any of the other tissues. In addition, 40 amniotic fluid samples obtained from women between 16 and 18 weeks of gestation, who underwent amniocentesis because of advanced maternal age, were tested using a fluorescent activated cell sorter. Among the amniotic fluid specimens examined, 18·4 ± 10·3 percent cells reacted with 7E12H12. Double immunofluorescence studies revealed that all Mc-Ab-stained cells contained secretory component, confirming that they were epithelial in origin. All fetuses whose amniotic fluid was analysed had normal karyotypes and amniotic fluid alpha-fetoprctein levels that were also normal. This study demonstrates that cell-specific Mc-Ab can be used to detect colon cells in the amniotic fluid and that colon cells contribute significant numbers in the mixture of amniotic fluid cells. This technique could be helpful in the prenatal diagnosis of disorders in which the flow of amniotic fluid through the fetal intestine is impaired, such as cystic fibrosis, imperforate anus, Hirschsprung aganglionic megacolon, and intestinal atresia.  相似文献   
104.
Environmental Fluid Mechanics - The action of wave dominated flow on river bank leads to retreatment of the bankline thereby causing intense erosion issues. The understanding of the bank erosion...  相似文献   
105.
Environmental Science and Pollution Research - Recent advancements and growing attention about free radicals (ROS) and redox signaling enable the scientific fraternity to consider their involvement...  相似文献   
106.
Environmental Science and Pollution Research - The COVID-19 pandemic has created unprecedented human health crisis in recent global history with rippling social and economic effects. The outbreak...  相似文献   
107.
Environmental Science and Pollution Research - In this study, lanthanum copper oxide was synthesized under hydrothermal techniques and characterized for doxycycline degradation. The catalyst...  相似文献   
108.
Apatani, a hill tribe of Arunachal Pradesh, India, has been practising rice fish culture traditionally for many decades. Their practice, locally termed aji ngui assonii, is free from the use of agro-chemicals and additional input of supplementary feed for fish. They basically follow the traditional agronomic practices for rice even in rice-fish combination pertaining to field preparation and maintenance. Field preparation starts in April, occasionally continues up to late May, and rice seedlings are planted in May-June. The strains of common carp are stocked at fry stage (3–5 cm), after just ten days of planting the rice and reared in the field for about 4 months in total. Sometimes they harvest fish partially from the field after an interval of 1.5 months. With multiple harvesting, only 200–300 kg ha-' offish are produced in each harvest whereas with final harvesting the production rate is 500 kg ha-'. The dykes of rice fields are utilized for growing millet in June and are harvested during August-September. The system of such integrated farming is an organic practice, as well as sustainable in the sense that it is based solely on available natural resources in the ecosystem and also preserves the agro-biodiversity, enhancing multidimensional support to the tribal livelihood.  相似文献   
109.
Pest management researchers currently reappraise the use of inert dust-based insecticides because of the growing problem of environmental pollution and increasing insect resistance associated with conventional insecticides. Diatomaceous earth, which is amorphous micron-sized silica derived from fossilized phytoplankton, has become popular as an alternative insecticidal agent in European countries. In this investigation the insecticidal efficacy of amorphous lipophilic silica nanoparticle was examined on red flour beetle (Tribolium castaneum), a stored grain insect pest. The biosafety of this silica nanoparticle formulation was studied in MRC-5 cell line with water-soluble tetrazolium and lactate dehydrogenase activity assays. Acute oral toxicity of these nanocides was studied in mice model following OECD guidelines for testing of chemicals as well as the effects of particle exposure on mouse blood parameters, serum biochemical levels, and histopathological changes in various organs.  相似文献   
110.
The rapid increase in the concentration of greenhouse gases in our atmosphere has led to significant changes in global climate. Methane is second to carbon dioxide in terms of its contribution to global warming. The wetlands serve as a major natural source of methane. Orissa State, located on the east coast of India, has a number of natural wetlands. Three representative wetlands: Chilka – the largest semi-saline lake of Asia, Anshupa – a land-locked fresh water lake and Gahirmatha – a tidal flood plain of Bhitara Kanika region that has sprawling mangrove vegetation (extension of the Sunderbans of the Gangetic delta) were chosen for intensive monitoring of water and sediment quality, along with methane flux over a period of three years during 1997–2000. The average seasonal methane fluxes were integrated to arrive at the annual flux from each wetland category. Finally, those results were extended to other natural wetlands of Orissa to arrive at the average annual methane flux of Orissa State. This is useful in calculating the total budget of greenhouse gases of India.  相似文献   
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