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101.
The cornerstone for an effective biomedical waste (BMW) management is appropriate waste segregation. Improper waste segregation practices can have an adverse impact on public health and increase the cost of treatment. Deficiencies in waste segregation practices can be corrected by continuous monitoring and education. Manpower for monitoring waste segregation in a large teaching hospital is scanty. We utilized the undergraduate medical students as monitors and studied the impact on waste segregation practices. A prospective observational study was carried out from August 2004 to January 2005. For monitoring waste segregation, the different areas of the hospital were divided amongst the II M.B.B.S students. They were provided with an observation sheet wherein the status of waste segregation and overall hygiene was recorded on a scale of 1-5. The impact of this programme was then analysed over the study period. The results indicated that a statistically significant improvement in waste segregation practices occurred in all areas. Thus, a large hospital with a medical college can identify students or a similar group for monitoring waste segregation or other aspects of biomedical waste management. This will improve their understanding of good practice in BMW management in future.  相似文献   
102.
103.
Accumulating data on the human fetal circulation shows the similarity to the experimental animal physiology, but with important differences. The human fetus seems to circulate less blood through the placenta, shunt less through the ductus venosus and foramen ovale, but direct more blood through the lungs than the fetal sheep. However, there are substantial individual variations and the pattern changes with gestational age. The normalised umbilical blood flow decreases with gestational age, and, at 28 to 32 weeks, a new level of development seems to be reached. At this stage, the shunting through the ductus venosus and the foramen ovale reaches a minimum, and the flow through the lungs a maximum. The ductus venosus and foramen ovale are functionally closely related and represent an important distributional unit for the venous return. The left portal branch represents a venous watershed, and, similarly, the isthmus aorta an arterial watershed. Thus, the fetal central circulation is a very flexible and adaptive circulatory system. The responses to increased afterload, hypoxaemia and acidaemia in the human fetus are equivalent to those found in animal studies: increased ductus venosus and foramen ovale shunting, increased impedance in the lungs, reduced impedance in the brain, increasingly reversed flow in the aortic isthmus and a more prominent coronary blood flow. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
104.
This paper attempts to capture the socially constructed nature of risk by analyzing the discourses embedded in community beliefs, myths and experiential narratives regarding coastal hazards and fishworkers' livelihoods. This paper draws insights from the works of James Scott on power and resistance in the everyday life of marginalized populations. Qualitative data for the study was collected using semi‐structured interview schedules, in‐depth group interviews, oral histories and storytelling across twenty marine fishing villages in Kerala. A significant finding of the study is that the communal discourse of coastal hazards or kolu is an integral part of fishworkers' resistance against formal authority and scientific knowledge systems in coastal management. The myths and beliefs of fishworkers are expressions of their concerns about present forms of development and coastal resource management.  相似文献   
105.
Trihalomethanes (THMs) the by-products of chlorination in water treatment are recognised as a threat to public health due to their carcinogenicity. The photodegradation of THMs using hydrogen peroxide has been found to give increased removal efficiency and the outcome of the study may find, its application in designing a unit process for water treatment. Batch experiments were carried out using UV lamp of 83 W and 40% w/w Hydrogen peroxide (H2O2) in test waters between 2.5–10 pH range of chloroform, bromodichloromethane, dibromochloromethane and bromoform at 50–200 μg L−1 initial concentration. 92–100% removal of chloroform, bromodichloromethane, dibromochloromethane and bromoform were found with 0.1% of H2O2 and 90 min of UV exposure.  相似文献   
106.
This short article reports on commercial composting slurry now available in India. The slurry culture containing active decomposer bacteria and enzymes is spread on the surface of the garbage and inside the heaps in windrows constructed at waste dump sites. The microbes produce hydrolysing enzymes to break down the long chain complexes of the organic substrates. About 1 kg of slurry culture in the colloidal emulsion form mixed with 20 litres of water is sprayed on about 3 m of solid waste. For one tonne of waste 200 litres of slurry water are needed. The waste heaps are turned once in 7 to 10 days for proper aeration and the inoculant slurry is sprayed at each turning to enhance decomposition and to maintain the proper moisture level which is usually 45–55 percent. The process is exothermic and the windrows reach a temperature of 70°–75°C within 24–36 hours, killing many harmful pathogens and repelling all birds, stray animals, flies and mosquitos from the dump site. The entire process is completed within 4–6 weeks and as the decomposition is completed the temperature falls to normal. About 40–45 percent of the undecomposed matter is of recyclable materials, and of the rest about 25–30 percent requires safe disposal in adjacent land-fill sites. The problem of emission from tip gases and of leachate and discharge of effluents is greatly reduced. The foul odor of the tip also disappears within 2–3 days of sanitization. The compost produced is rich in sodium, potassium and phosphorous as well as certain trace elements, and contains active nitrogen fixing and phosphate solubulising bacteria.  相似文献   
107.
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   
108.
Fingerlings of Labeo rohita subjected to sublethal unionized ammonia (0.132mg/l) for 30 days exhibited significant changes. Increase in haemoglobin, haematocrit, plasma cortisol, plasma glucose, plasma cholesterol and plasma lactic acid levels whereas, decrease in plasma chloride, liver and muscle glycogen, hepatosomatic index and DNA/RNA ratio of muscles with stable plasma protein was observed. Metabolic recovery was not observed within 30 days of exposure.  相似文献   
109.
Environment, Development and Sustainability - Watersheds in the subtropical Himalayan basins are highly prone to land degradation due to deforestation, landslides, intensive agriculture, population...  相似文献   
110.
Mutations for activity level, designated hpa and hra, in Drosophila jambulina altered properties of the pacemaker controlling eclosion rhythm. Entrainment of eclosion rhythm was studied in light-dark (LD) cycles of 12:12 h at 28°C. The wild type strain entrained to LD cycles but the hpa or hra strain did not. When these strains were released from constant light (LL) to constant darkness (DD), the wild type strain free-ran while other two strains were arrhythmic. Temperature cycles entrained the wild type and hpa strain in DD and LL, and when transferred to constant temperature following thermoperiodic entrainment, the wild type strain free-ran in DD, while the hpa strain free-ran in LL as if the input of LL was essential for its free-running state. Temperature cycles entrained the hra strain in DD but not in LL, and free-running rhythmicities were never established, suggesting that the hra mutation has altered the basic properties of its pacemaker.  相似文献   
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