• Title/Summary/Keyword: Sources of stress

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Study on the Impacts and Countermeasures of Climate Change on Livestock Agriculture (축산부문에 미치는 기후변화의 영향 및 대응방안 연구)

  • Ji, Eun-Sook;Park, Kyu-Hyun
    • Journal of Animal Environmental Science
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    • v.21 no.2
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    • pp.47-54
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    • 2015
  • Climate change has directly impacted environmentally dependent first industry. The changes of amount and frequency of precipitation have caused unstable drinking water supply for grassland and feed crop, and have changed the variety of grassland and feed crop. Rising temperature has caused heat stress on livestock, which has impacted feed intake and livestock products, and also has threatened to the health of livestock by widening the range of sources of diseases. In order for livestock industry to confront climate change, new technology development for climate change adaptation and measures of greenhouse gas mitigation are essential. Agroforestry is the one of alternative measures to mitigate greenhouse gases and to adapt to climate change. Agroforestry is the way rearing livestock and cultivating plants in forest, which is suitable to Korea where mountain area is over 68%. Feedstock such as maize, soybean, rice, and grass grown by agroforestry would decrease feed cost. Agroforestry will decrease heat stress of livestock during hot weather and will be possible to pasture, which increases livestock welfare.

The Effects of Social Support on Depression of Older People in Local Small Cities (사회적 지지가 중소도시 노인의 우울에 미치는 영향)

  • Kim, Jung-Yoo;Choi, Youseok
    • The Journal of the Korea Contents Association
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    • v.15 no.4
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    • pp.208-219
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    • 2015
  • Using 492 older people in Chuncheon, this study examines whether social support is associated with depression of older people. Findings show that stress is positively associated with depression. Social support is negatively related to depression of older people. Analysis on the sources of social support reveals that all of the supports from families, friends, and important others are negatively associated with depression of the elderly. However, buffering effects of social support is not confirmed. Depression of older people is also associated with gender, household type, economic activity participation, and chronic diseases. Based on the findings, this study provides suggestions to prevent depression of older people and future research agenda.

Inhibition of Oxidative Stress and Enhancement of Cellular Activity by Mushroom Lectins in Arsenic Induced Carcinogenesis

  • Rana, Tanmoy;Bera, Asit Kumar;Das, Subhashree;Bhattacharya, Debasis;Pan, Diganta;Das, Subrata Kumar
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.9
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    • pp.4185-4197
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    • 2016
  • Chronic arsenicosis is a major environmental health hazard throughout the world, including India. Animals and human beings are affected due to drinking of arsenic contaminated ground water, due to natural mineral deposits, arsenical pesticides or improperly disposed arsenical chemicals. Arsenic causes cancer with production of free radicals and reactive oxygen species (ROS) that are neutralized by an elaborate antioxidant defense system consisting of enzymes and numerous non-enzymatic antioxidants. Dietary antioxidant supplements are useful to counteract the carcinogenesis effects of arsenic. Oyster mushroom lectins can be regarded as ingredients of popular foods with biopharmaceutical properties. A variety of compounds have been isolated from mushrooms, which include polysaccharides and polysaccharopeptides with immune-enhancing effects. Lectins are beneficial in reducing arsenic toxicity due to anticarcinogenetic roles and may have therapeutic application in people suffering from chronic exposure to arsenic from natural sources, a global problem that is especially relevant to millions of people on the Indian subcontinent.

Performance of cyclone separator for syngas production in downdraft gasifier

  • Kumara, Sunil;Shukla, S.K.
    • Advances in Energy Research
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    • v.4 no.3
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    • pp.223-237
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    • 2016
  • The excess use of conventional sources of energy by the industries and power sector result in acute shortage of energy produced by fossil fuel. To overcome this energy crisis, biomass feedstock is used to produce syngas or producer gas. For cleaning the dust particle present in the producer gas cyclone separators are largely used. In this paper we investigate the performance parameters of cyclone separator mainly efficiency and pressure drop for different feedstock. Cyclone performance has been evaluated based on experimentation and empirical approach using Leith and Licht model. The same has also been calculated by using turbulent RSM in Ansys Fluent for Wood and Coconut shell feedstock. Experimental results show that using feed stock with 10 % Calcium oxide (CaO) by weight, the efficiency of cyclone got reduced from 71.87% to 70.75% for wood feed stock, whereas in case of coconut shell, the cyclone efficiency got reduced from 78% to 73.44%. It is also seen that Leith and Licht model and Reynolds stress model (RMS) predicts very close to the particle collection efficiency evaluated by using experimental data.

Countermeasure on High Vibration of Branch Pipe with Pressure Pulsation Transmitted from Main Steam Header (주증기 배관 헤더의 압력맥동에 대한 분기 배관의 고진동 대책)

  • Kim, Yeon-Whan;Bae, Yong-Chae;Lee, Young-Shin
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.15 no.8 s.101
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    • pp.988-995
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    • 2005
  • Vibration has been severly increased at the branch pipe of main steam header since the commercial operation of nuclear power plant. Intense broad band disturbance flow at the discontinuous region such as elbow, valve, and header generates the acoustical pulsation which is propagated through the piping system. The pulsation becomes the source of low frequency vibration at piping system. If it coincide with natural frequency of the pipe system, excessive vibration is made. High level vibration due to the pressure pulsation related to high dynamic stress, and ultimately, to failure probability affects fatally the reliability and confidence of plant piping system. This paper discusses vibration effect for the branch pipe system due to acoustical pulsations by broad band disturbance flow at the large main steam header in 700 MW nuclear power plant. The exciting sources and response of the piping system are investigated by using on-site measurements and analytical approaches. It is identified that excessive vibration is caused by acoustical pulsations of 1.3 Hz, 4.4 Hz and 6.6 Hz transmitted from main steam balance header, which are coincided with fundamental natural frequencies of the piping structure. The energy absorbing restraints with additional stiffness and damping factor were installed to reduce excessive vibration.

Vibration Effect for Branch Pipe System due to Main Steam Header Pulsation (주증기 배관 헤더의 맥동이 분기 배관에 미치는 영향)

  • Kim, Yeon-Whan;Bae, Yong-Chae;Lee, Hyun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.05a
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    • pp.780-785
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    • 2005
  • Vibration has been severly increased at the branch pipe of main steam header since the commercial operation of a nuclear power plant. Intense broad band disturbance flow at the discontinuous region such as elbow, valve or heather generates the acoustical pulsation which is propagated through the piping system. The pulsation becomes the source of low frequency vibration at piping system. If it coincide with natural frequency of the pipe system, excessive vibration is made. High level vibration due to the pressure pulsation related to high dynamic stress, and ultimately, to failure probability affects fatally the reliability and confidence of plant piping system. This paper discusses vibration effect for the branch pipe system due to acoustical pulsations by broad band disturbance flow at the large main steam header in 7nn nuclear power plant. The exciting sources and response or the piping system are investigated by using on site measurements and analytical approaches. It is identified that excessive vibration is caused by acoustical pulsations of 1.3Hz, 4.4Hz and 6.6Hz transferred from main steam header, which are coincided with fundamental natural frequencies of the piping structure. The energy absorbing restraints with additional stiffness were installed to reduce excessive vibration.

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Halotolerant Plant Growth Promoting Bacteria Mediated Salinity Stress Amelioration in Plants

  • Shin, Wansik;Siddikee, Md. Ashaduzzaman;Joe, Manoharan Melvin;Benson, Abitha;Kim, Kiyoon;Selvakumar, Gopal;Kang, Yeongyeong;Jeon, Seonyoung;Samaddar, Sandipan;Chatterjee, Poulami;Walitang, Denver;Chanratana, Mak;Sa, Tongmin
    • Korean Journal of Soil Science and Fertilizer
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    • v.49 no.4
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    • pp.355-367
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    • 2016
  • Soil salinization refers to the buildup of salts in soil to a level toxic to plants. The major factors that contribute to soil salinity are the quality, the amount and the type of irrigation water used. The presented review discusses the different sources and causes of soil salinity. The effect of soil salinity on biological processes of plants is also discussed in detail. This is followed by a debate on the influence of salt on the nutrient uptake and growth of plants. Salinity decreases the soil osmotic potential and hinders water uptake by the plants. Soil salinity affects the plants K uptake, which plays a critical role in plant metabolism due to the high concentration of soluble sodium ($Na^+$) ions. Visual symptoms that appear in the plants as a result of salinity include stunted plant growth, marginal leaf necrosis and fruit distortions. Different strategies to ameliorate salt stress globally include breeding of salt tolerant cultivars, irrigation to leach excessive salt to improve soil physical and chemical properties. As part of an ecofriendly means to alleviate salt stress and an increasing considerable attention on this area, the review then focuses on the different plant growth promoting bacteria (PGPB) mediated mechanisms with a special emphasis on ACC deaminase producing bacteria. The various strategies adopted by PGPB to alleviate various stresses in plants include the production of different osmolytes, stress related phytohormones and production of molecules related to stress signaling such as bacterial 1-aminocyclopropane-1-carboxylate (ACC) derivatives. The use of PGPB with ACC deaminase producing trait could be effective in promoting plant growth in agricultural areas affected by different stresses including salt stress. Finally, the review ends with a discussion on the various PGPB activities and the potentiality of facultative halophilic/halotolerant PGPB in alleviating salt stress.

Ingestion of Gouda Cheese Ameliorates the Chronic Unpredictable Mild Stress in Mice

  • Yun, Bohyun;Yoo, Ja Yeon;Park, Mi Ri;Ryu, Sangdon;Lee, Woong Ji;Choi, Hye Jin;Kang, Min Kyoung;Kim, Younghoon;Oh, Sangnam
    • Food Science of Animal Resources
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    • v.40 no.1
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    • pp.145-153
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    • 2020
  • Depression is a kind of mood disorder characterized by decline in motivation, interest, attention, mental activity, and appetite. Although depression is caused by a variety of causes, including genetic, endocrine and environmental stress, mild depression has been reported to improve with diet. Therefore, various type of food sources including functional and nutritional supplement are required to treat the depressive patients. Cheese contains bioactive peptides that have beneficial effects on host health. In particular, Jersey milk has been reported to contain higher solids than does Holstein milk. This study investigated the effects of Gouda cheese from Jersey and Holstein milk on chronic, unpredictable, mildly stressed (CUMS) mice. Here, spontaneous alterations in cheese-fed stressed mice were noted to be effectively recovered with statistical significance regardless cow species. Interestingly, for the analysis of fecal microbiota, Bacteroidetes were noted to increase with a reduction in Firmicutes at the phylum level with Jersey cheese. Taken together, we suggest that cheese intake provided a beneficial effect on stressed mice in recovering recognition ability. In particular, changes in internal microbiota were observed, suggesting that the bioactive ingredients in cheese act as improvement agents with respect to mood and brain function.

Differential settlements in foundations under embankment load: Theoretical model and experimental verification

  • Wang, Changdan;Zhou, Shunhua;Wang, Binglong;Guo, Peijun;Su, Hui
    • Geomechanics and Engineering
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    • v.8 no.2
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    • pp.283-303
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    • 2015
  • To research and analyze the differential settlements of foundations specifically, site investigations of existing railways and metro were firstly carried out. Then, the centrifugal test was used to observe differential settlements in different position between foundations on the basis of investigation. The theoretical model was established according to the stress diffusion method and Fourier method to establish an analytical solution of embankment differential settlement between different foundations. Finally, theoretical values and experimental values were analyzed comparatively. The research results show that both in horizontal and vertical directions, evident differential settlement exists in a limited area on both sides of the vertical interface between different foundations. The foundation with larger elastic modulus can transfer more additional stress and cause relatively less settlement. Differential settlement value decreases as the distance to vertical interface decreases. In the vertical direction of foundation, mass differential settlement also exists on both sides of the vertical interface and foundation with larger elastic modulus can transfer more additional stress. With the increase of relative modulus of different foundations, foundation with lower elastic modulus has larger settlement. Meanwhile, differential settlement is more obvious. The main error sources in theoretical and experimental values include: (a) different load form; (b) foundation characteristics differences; (c) modulus conversion; (d) effect of soil internal friction.

Nephroprotective effect of astaxanthin against trivalent inorganic arsenic-induced renal injury in wistar rats

  • Wang, Xiaona;Zhao, Haiyuan;Shao, Yilan;Wang, Pei;Wei, Yanru;Zhang, Weiqian;Jiang, Jing;Chen, Yan;Zhang, Zhigang
    • Nutrition Research and Practice
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    • v.8 no.1
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    • pp.46-53
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    • 2014
  • Inorganic arsenic (iAs) is a toxic metalloid found ubiquitously in the environment. In humans, exposure to iAs can result in toxicity and cause toxicological manifestations. Arsenic trioxide ($As_2O_3$) has been used in the treatment for acute promyelocytic leukemia. The kidney is the critical target organ of trivalent inorganic As ($iAs^{III}$) toxicity. We examine if oral administration of astaxanthin (AST) has protective effects on nephrotoxicity and oxidative stress induced by $As_2O_3$ exposure (via intraperitoneal injection) in rats. Markers of renal function, histopathological changes, $Na^+-K^+$ ATPase, sulfydryl, oxidative stress, and As accumulation in kidneys were evaluated as indicators of $As_2O_3$ exposure. AST showed a significant protective effect against $As_2O_3$-induced nephrotoxicity. These results suggest that the mechanisms of action, by which AST reduces nephrotoxicity, may include antioxidant protection against oxidative injury and reduction of As accumulation. These findings might be of therapeutic benefit in humans or animals suffering from exposure to $iAs^{III}$ from natural sources or cancer therapy.