Acute toxicity of 0.3 ppm mercuric chloride on the mucocytes of the branchial diverticulum and skin of Heteropneustes fossilis results in cyclic increases followed by decreases in the density, area occupancy and volum...Acute toxicity of 0.3 ppm mercuric chloride on the mucocytes of the branchial diverticulum and skin of Heteropneustes fossilis results in cyclic increases followed by decreases in the density, area occupancy and volume at different intervals of exposure. The alterations in the two tissues do not follow the same path perhaps due to different modes of action of the mercury salt: The skin comes under direct contact effects, while the branchial diverticulum may be affected by hormonal imbalance caused by a stress effect.展开更多
Histopathological alterations induced by the sublethal concentration of (0.03 ppm) mercuric chloride solution on the epidermis of the fresh-water catfish Heteropneuates fossilis have been studied. It induces slow but ...Histopathological alterations induced by the sublethal concentration of (0.03 ppm) mercuric chloride solution on the epidermis of the fresh-water catfish Heteropneuates fossilis have been studied. It induces slow but significant histopathological changes in the various cellular components of the epidermis. It induces vacuolization, necrosis and pycnosis of the nuclei of the epithelial cells which subsequently shed. Loosening of epithelial cells of the outermost and middle layers following degeneration of the intercellular material and widened intercellular spaces is another important alteration. Prolonged mercury treatment also causes a gradual decrease in staining intensity for sulphated glycosaminoglycans in the outer border of the most superficial layer epithelial cells. The glandular elements (club cells and mucocytes) also get affected, showing cyclic degeneration followed by regeneration.展开更多
Heavy smog shrouded China's central and eastern regions for days this past January, and experts are advising citizens to stay inside. But how much safer is our indoor air? The U.S. Environmental Protection Agency'...Heavy smog shrouded China's central and eastern regions for days this past January, and experts are advising citizens to stay inside. But how much safer is our indoor air? The U.S. Environmental Protection Agency's research shows that 24 million people in the world die every year as a result of poor indoor air quality, said Song Guangsheng, Secretary General of China's Indoor Environment Test Center (CIETC).展开更多
Ecotourism blossoms in the Qinling Mountains Mountains are everywhere, and rivers flow in almost every valley. This is the Qinling Mountains, a major eastto-west range in southern Shaanxi Province,
There are some special spaces in which there is no air conditioning or the people are in move,thus exposing people to a hot environment.In this study,portable cooling systems were proposed and their effects on thermal...There are some special spaces in which there is no air conditioning or the people are in move,thus exposing people to a hot environment.In this study,portable cooling systems were proposed and their effects on thermal comfort and work performance were investigated at an air temperature of 32°C.Four conditions were established:cool air towards breathing zone(A),chest and back cooling(B)#combined cooling(C)and no cooling(D).Twenty-eight subjects were exposed to the four conditions in a counterbalanced order.During each exposure they performed tasks and made subjective assessments,while multiple physiological parameters were measured.Compared with no cooling(D),cool air towards breathing zone(A)and chest and back cooling(B)improved work performance by 17.5%and 19.25%,respectively,while decreased the subjects'thermal sensation,skin temperature,and heart rate.When the two cooling systems were combined(C),larger improvements in thermal comfort and work performance were achieved than no cooling(D);the mean thermal sensation rating decreased from 2.4 to 0.7;work performance increased by up to 33%,and physiological parameters including skin temperature,pulse,heart rate and salivary alpha-amylase significantly decreased.The present results suggest that the proposed portable cooling systems could maintain thermal comfort and work performance in a hot environment,while potentially improve air quality for some special spaces.展开更多
文摘Acute toxicity of 0.3 ppm mercuric chloride on the mucocytes of the branchial diverticulum and skin of Heteropneustes fossilis results in cyclic increases followed by decreases in the density, area occupancy and volume at different intervals of exposure. The alterations in the two tissues do not follow the same path perhaps due to different modes of action of the mercury salt: The skin comes under direct contact effects, while the branchial diverticulum may be affected by hormonal imbalance caused by a stress effect.
基金Supported by the University Grants Commission,Govt.of India,New Delhi Project No.F.3-66/89(SR-Ⅱ).
文摘Histopathological alterations induced by the sublethal concentration of (0.03 ppm) mercuric chloride solution on the epidermis of the fresh-water catfish Heteropneuates fossilis have been studied. It induces slow but significant histopathological changes in the various cellular components of the epidermis. It induces vacuolization, necrosis and pycnosis of the nuclei of the epithelial cells which subsequently shed. Loosening of epithelial cells of the outermost and middle layers following degeneration of the intercellular material and widened intercellular spaces is another important alteration. Prolonged mercury treatment also causes a gradual decrease in staining intensity for sulphated glycosaminoglycans in the outer border of the most superficial layer epithelial cells. The glandular elements (club cells and mucocytes) also get affected, showing cyclic degeneration followed by regeneration.
文摘Heavy smog shrouded China's central and eastern regions for days this past January, and experts are advising citizens to stay inside. But how much safer is our indoor air? The U.S. Environmental Protection Agency's research shows that 24 million people in the world die every year as a result of poor indoor air quality, said Song Guangsheng, Secretary General of China's Indoor Environment Test Center (CIETC).
文摘Ecotourism blossoms in the Qinling Mountains Mountains are everywhere, and rivers flow in almost every valley. This is the Qinling Mountains, a major eastto-west range in southern Shaanxi Province,
基金This work was supported by the National Natural Science Foundation of China(No.51778359 and No.51478260)the State Key Laboratory of Air Conditioning Equipment and System Energy Conservation(No.ACSKL2018KT04)。
文摘There are some special spaces in which there is no air conditioning or the people are in move,thus exposing people to a hot environment.In this study,portable cooling systems were proposed and their effects on thermal comfort and work performance were investigated at an air temperature of 32°C.Four conditions were established:cool air towards breathing zone(A),chest and back cooling(B)#combined cooling(C)and no cooling(D).Twenty-eight subjects were exposed to the four conditions in a counterbalanced order.During each exposure they performed tasks and made subjective assessments,while multiple physiological parameters were measured.Compared with no cooling(D),cool air towards breathing zone(A)and chest and back cooling(B)improved work performance by 17.5%and 19.25%,respectively,while decreased the subjects'thermal sensation,skin temperature,and heart rate.When the two cooling systems were combined(C),larger improvements in thermal comfort and work performance were achieved than no cooling(D);the mean thermal sensation rating decreased from 2.4 to 0.7;work performance increased by up to 33%,and physiological parameters including skin temperature,pulse,heart rate and salivary alpha-amylase significantly decreased.The present results suggest that the proposed portable cooling systems could maintain thermal comfort and work performance in a hot environment,while potentially improve air quality for some special spaces.