• 환경위생공학
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• 제6권2호
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• pp.17-31
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• 1991

The effects of environmental agents on health are great concern for all. It was recognized that each human has differential susceptibility to environmental effects. Susceptibility are changed by many factors includin gdevelopmpntal processes, genetic factors, nutritional stratus, preexisting disease conditions, life style and personal habits. Of all factors nutritional factors seem to be the area most modifiable. Consequently, It is an area that must be more thoroughly evaluated. In this paper, nutrient and environment interactions are reviewed briefly with published literatures. This paper deals with the influence of micronutrients(energy, protein and fat), Vitamins (vitamin 4, vitamin B-complex, vitamin C, vitamin D and vitamin I) and Minerals(calcium, iron, selenium, zinc and other minerls) on environmental effects. The role of arch nutrient was assessed in modifyine the expression of environmental pollutant toxicity with available litertures. In each nutrient section, the effect of environment was considered in following agents : heavy metals(lead, cadmium, mercury, silver and etc), inorganic agents(nitwits, sulfite, fluoride and etc), organic agents(benzene, carbon tatra-chloride, aflatoxin, auto dye, dialbrin etc), Irritant gas(ozone, carbon monooxide and etc), physical agents(X-irradiation, ultra violet, temperature and noise) and insectcides. The extent to which nutritional status modifies environmental effects 3nd its converse, how envirollments affects nutritional status is very complex. In deed, at the present time there are more than 50 chelnical/phycical agents that affect the nutrient metabolism and/or have their toxicity either directly diminished or enhanced by nutrients of those agents, small number of agents for each nutrients have sufficient evidence to warrant any reasonable degree of confidence in their hypothesized associtation. With these information at this present time it is hard to conclude that the recommended dietary allowance for each nutrient should be reconsidered.

• KIEAE Journal
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• 제11권3호
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• pp.31-36
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• 2011

People spend most of their time inside buildings recently, so the indoor air quality is one of the most important factors to human health. Furthermore, minimum energy use with proper ventilation systems for pleasant indoor environment is necessary because of energy shortage over the world. The concern to maintain proper indoor air quality at home has been increased, and a proper indoor air quality is continuously requested by the residents. By measuring and analyzing the density fluctuation of $CO_2$ through indoor humidity and testing personal reactions regarding comfort condition, we can obtain a way to effective ventilation. Heat and carbon dioxide emissions from resident's metabolism and construction materials could be the causes of indoor air pollution. If these materials stay indoors for a long time, it could directly influence the resident's health condition with diseases. It also leads massive energy use. Therefore, the way to save energy and to have effective control of indoor ventilation is needed. This study presented the control method of bedroom ventilation by $CO_2$ concentration change and subjective evaluation.

• KIEAE Journal
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• 제10권1호
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• pp.19-24
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• 2010

Modern people are spending most of time in interior area. Indoor air environmental problem is one of the most effective factors influenceable to human health. Furthermore, saving energy and making ventilation system for pleasant indoor environment are necessary when it is faced shortage of energy over the world. In our country's case, it is already imposed that required quantity of air ventilation in buildings is 0.7 times per hour on "The regulation on building engineering system". As on the rise of the interests about Indoor air environment, Heat and Carbon dioxide emissions from User's metabolism, activity, furniture, and construction materials etc. could be the causes of Indoor air pollution. If these materials stays in Indoor air for so long, it could directly influence the user's health condition with a disease. As of building's sterilization improved that raised more mechanical ventilation. It also leads much energy waste in a period of high price of fossil fuel. Therefore, the way that saves energy and effective control of indoor ventilation is urgently needed. So, this study places the purpose on validating volume of indoor ventilation and user's comfortable degree by comparison CO2 emission rate through changing floor temperature.

• Journal of Microbiology and Biotechnology
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• 제33권4호
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• pp.485-492
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• 2023

Methylorubrum extorquens, a facultative methylotroph, assimilates C₁ compounds and accumulates poly-β-hydroxylbutyrate (PHB) as carbon and energy sources. The ethylmalonyl pathway is central to the carbon metabolism of M. extorquens, and is linked with a serine cycle and a PHB biosynthesis pathway. Understanding the ethylmalonyl pathway is vital in utilizing methylotrophs to produce value-added chemicals. In this study, we determined the crystal structure of the mesaconyl-CoA hydratase from M. extorquens (MeMeaC) that catalyzes the reversible conversion of mesaconyl-CoA to β-methylmalyl-CoA. The crystal structure of MeMeaC revealed that the enzyme belongs to the MaoC-like dehydratase domain superfamily and functions as a trimer. In our current MeMeaC structure, malic acid occupied the substrate binding site, which reveals how MeMeaC recognizes the β-methylmalyl-moiety of its substrate. The active site of the enzyme was further speculated by comparing its structure with those of other MaoC-like hydratases.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.59-59
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• 2017

Rice (Oryza sativa L.) is the most important crop and its yield must be improved to feed the increasing global population. Recently developed high-yielding varieties with extra-large sink capacity often have a problem in unstable grain-filling. Therefore, understanding limiting factors for improving grain-filling and controlling them are essential for further improvement of rice grain yield. However, since grain-filling rate was determined by complex sink-source balance, the ability of grain-filling was very difficult to evaluate. Source ability for 'grain' was not only determined by the ability of carbon assimilation in leaves, but also that of carbon translocation from leaves to panicles. Sink strength was determined by the complex carbon metabolism from sucrose degradation to starch synthesis. Hence, to evaluate the grain-filling ability and determine its regulatory steps, the whole picture of carbon flow from photosynthesis at leaves to starch synthesis at grains must be revealed in a metabolite level. In this study, the yield and grain growth rate of three high-yielding varieties, which show high sink capacity commonly, were compared. Momiroman showed lower grain filling rate and slower grain growth rate than the other varieties, Hokuriku 193 and Tequing. To clarify the limiting point in the carbon flow of Momiroman, $CO_2$ labeled by stable isotope ($^{13}C$) was fed to three varieties during ripening period. The ratio of $^{13}C$ left in the stem was higher in Momiroman 24 hours after feeding, suggesting inefficient carbon translocation of Momiroman. More interestingly, $^{13}C$ translocation from soluble fraction to insoluble one in the grain seemed to be slower in Momiroman. To get the further insight in a metabolite level, we are now trying the $^{13}C$ labeling metabolome analysis in the developing grains.

• The Korean Journal of Physiology
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• 제3권1호
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• pp.11-18
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• 1969

Tissue homogenates of 10 kinds of human cancer tissues were incubated in medium containing either one of $C^{14}-1,\; C^{14}-2,\;or\; C^{14}-3-lactate $ as a substrate in order to observe the oxidative pathway of lactate in cancer tissues. Lactate concentration in incubation medium was maintained at 50 mg%. At the end of incubation period, gas samples and incubation media were analyzed for total $CO_2$ production rates, radioactivities of respiratory $CO_2$, lactate uptake rates and pyruvate appearance rates. The following results were obtained. 1. Lactate uptake rates in all of cancer tissues examined were less than $2.5\;{\mu}M/hr/gm$ and much lower than those in normal tissues. 2. In the 10 kind of human cancer tissues, total $CO_2$ production rates were less than $10\;{\mu}M/hr/gm$, in all cases. These lower values impressed that oxidative metabolism in tumor tissues generally inhibited as compared with that in normal tissue. On the other hand, fractions of $CO_2$ derived from lactate to total $CO_2$ production rates were less than 15% except one case These facts showed that oxidation of lactate into $CO_2$ was greatly inhibited in tumor tissues. 3. Respiratory $CO_2$ yields from C-1 carbon of lactate in various cancer tissues were mean of 77.7% of total $CO_2$ yield from lactate and $CO_2$ yields from C-2 and C-3 carbon of lactate were mean of 9.1% and 12.6% respectively. These facts showed that carboxyl carbon of lactate oxidized more easily than ${\alpha}\;and\;{\beta}$ carbon of lactate. 4. In 10 kinds of cancer tissues, fractions of disappeared lacteate from media into $CO_2$ and pyruvate, which expressed as RLD $co_2$ and RLDpy respectively, were about 5% in except 3 cases and less than 3% except one case. These fact showed that almost of disappeared lactate from media were degraded into compounds other than $CO_2$ and pyruvate. From the above date, it was suggested that in the oxidative pathway of lactate in cancer tissues $CO_2$ was easily Produced from carboxyl carbon of lactate by oxidative decarboxylation as in the normal tissue, and further oxidation of 2 carbon unit via TCA cycle was inhibited.

• 한국물환경학회지
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• 제36권4호
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• pp.284-299
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• 2020

Dam reservoirs play a particularly crucial role in processing the allochthonous and the autochthonous dissolved (DOC) and the particulate (POC) organic carbon and in the budget of global carbon cycle. However, the complex physical and biogeochemical processes make it difficult to capture the temporal and spatial dynamics of the DOC and the POC in reservoirs. The purpose of this study was to simulate the dynamics of the DOC and the POC in Daecheong Reservoir using the 3-D hydrodynamics and water quality model (AEM3D), and to quantify the mass balance through the source and sink fluxes analysis. The AEM3D model was calibrated using field data collected in 2017 and showed reasonable performance in the water temperature and the water quality simulations. The results showed that the allochthonous and autochthonous proportions of the annual total organic carbon (TOC) loads in the reservoir were 55.5% and 44.5%, respectively. In season, the allochthonous loading was the highest (72.7%) in summer, while in autumn, the autochthonous loading was the majority (77.1%) because of the basal metabolism of the phytoplankton. The amount of the DOC discharged to downstream of the dam was similar to the allochthonous load into the reservoir. However, the POC was removed by approximately 96.6% in the reservoir mainly by the sedimentation. The POC sedimentation flux was 36.21 g-C/㎡/yr. In terms of space, the contribution rate of the autochthonous organic carbon loading was high in order of the riverine zone, the transitional zone, and the lacustrine zone. The results of the study provide important information on the TOC management in the watersheds with extensive stagnant water, such as dam reservoirs and weir pools.

• Environmental Engineering Research
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• 제12권4호
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• pp.136-147
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• 2007

In an effort to identify possible microbes for seeking bioagents for remediation of herbicide-contaminated soils, seven species of phototrophic nonsulfur bacteria (Rhodobacter capsulatus and sphaeroides, Rhodospirillum rubrum, Rhodopseudomonas acidophila, blastica and viridis, Rhodomicrobium vannielii) were grown in the presence of the herbicide, butachlor, and bacterial growth rates and nitrogen fixation were measured with different carbon sources. Under general conditions, all species showed 17-53% reductions in growth rate following butachlor treatment. Under nitrogen-fixing conditions, Rb. capsulatus and Rs. rubrum showed 1-4% increases in the growth rates and 2-10% increases in nitrogen-fixing abilities, while the other 5 species showed decreases of 17-47% and 17-85%, respectively. The finding that Rp. acidophila, Rp. blastica, Rp. viridis and Rm. vannielii showed stronger inhibitions of nitrogenase activity seems to indicate that species in genera Rhodobacter and Rhodospirillum are less influenced by butachlor than those in Rhodopseudomonas and Rhodomicrobium in terms of nitrogen-fixing ability. Overall, nitrogenase activity was closely correlated with both growth rate and glutamine synthetase activity (representing nitrogen metabolism). When the carbon sources were compared, pyruvate (three carbons) was best for all species in terms of growth rate and nitrogen fixation, with malate (four carbons) showing intermediate values and ribose(five carbons) showing the lowest; these trends did not change in response to butachlor treatment. We verified that each of the 7 species had a plasmid ($12.2{\sim}23.5\;Kb$). We found that all 7 species could use butachlor as a sole carbon source and 3 species were controlled by plasmid-born genes, but it is doubtful whether plasmid-born genes were responsible to nitrogen fixation.

• 한국응용과학기술학회지
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• 제36권4호
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• pp.1420-1426
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• 2019

Dawley 계 숫컷 흰쥐(200~210g)를 정상군, CCl₄-대조군, CCl₄-실험군으로 나누어 실험군은 애엽 에탄올 추출물을 1,000mg/kg,b.w의 용량으로 1일1회7일간 경구 투여 후 사염화탄소를 0.6mg/kg,b.w의 용량으로 복강내 주사 후 다음날 개복하여 혈청내의 Alanine aminotransferase(ALT), Aspartate aminotransferase(AST),Alkaline phosphatase(ALP), Glutamyltranspeptidase(γ-GT), Lactate dehydrogenase(LDH)의 활성도와 중성지방, 콜레스테롤 함량을 측정한 결과 애엽 추출물 투여군에서 CCl₄-대조군과 비교하여 유의적인 감소를 나타내었으며, HDL-콜레스테롤은 유의적인 증가를 나타내었다. 간조직중의 지질과산화 함량은 감소를 glutathione함량은 유의적인 증가를 나타내었다 이 실험 결과 애엽 에탄올 추출물은 사염화탄소 투여에 의한 간 손상을 억제하는 보호물질을 함유하고 있음을 알 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제29권11호
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• pp.1593-1600
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• 2016

This research was conducted to investigate the physiological consequences of undernourished yak. Twelve Maiwa yak ($110.3{\pm}5.85kg$) were randomly divided into two groups (baseline and starvation group). The yak of baseline group were slaughtered at day 0, while the other group of yak were kept in shed without feed but allowed free access to water, salt and free movement for 9 days. Blood samples of the starvation group were collected on day 0, 1, 2, 3, 5, 7, 9 and the starved yak were slaughtered after the final blood sample collection. The liver and muscle glycogen of the starvation group decreased (p<0.01), and the lipid content also decreased while the content of moisture and ash increased (p<0.05) both in Longissimus dorsi and liver compared with the baseline group. The plasma insulin and glucose of the starved yak decreased at first and then kept stable but at a relatively lower level during the following days (p<0.01). On the contrary, the non-esterified fatty acids was increased (p<0.01). Beyond our expectation, the ketone bodies of ${\beta}$-hydroxybutyric acid and acetoacetic acid decreased with prolonged starvation (p<0.01). Furthermore, the mRNA expression of lipogenetic enzyme fatty acid synthase and lipoprotein lipase in subcutaneous adipose tissue of starved yak were down-regulated (p<0.01), whereas the mRNA expression of lipolytic enzyme carnitine palmitoyltransferase-1 and hormone sensitive lipase were up-regulated (p<0.01) after 9 days of starvation. The phosphoenolpyruvate carboxykinase and pyruvate carboxylase, responsible for hepatic gluconeogenesis were up-regulated (p<0.01). It was concluded that yak derive energy by gluconeogenesis promotion and fat storage mobilization during starvation but without ketone body accumulation in the plasma.