• 환경위생공학
• /
• 제7권2호
• /
• pp.95-110
• /
• 1992

Much progress has been made in understanding the subcellular events of the human lung injuries after acute exposure to environmental air pollutants. Host of those events represent oxidative damages mediated by reactive oxygen species such as superoxide, hydrogen peroxide, and the hydroxy, free radical. Recently, nitric oxide (NO) was found to be endogenously produced by endothelial cells and cells of the reticulo-endothelial system as endothelialderived relaxation factor (EDRF) which is a vasoactive and neurotransmitter substance. Together with superoxide, NO can form another strong oxidant, peroxonitrite. The relative importance of exogenous sources of $N0/N0_2$ and endogenous production of NO by the EDRF producing enzymes in the oxidative stresses to the heman lung has to be elucidated. The exact events leading to chronic irreversible damage are still yet to be known. From chronic exposure to oxidant gases, progressive epithelial and interstitial damages develop. Type I epithelial cells become thicker and cover a smaller average alveolar surface area while thee II cells proliferate instead. Under acute damages, the extent of loss of the alveolar epithelial cell lining, especially type II cells appears to be a good predictor of the ensuing irreversible damage to alveolar compartment. Interstitial matrix undergo remodeling during chronic exposure with increased collagen fibers and interstitial fibroblasts. However, Inany of these changes can be reversed after cessation of exposure. Among chronic lung injuries, genetic damages and repair responses received particular attention in view of the known increased lung cancer risks from exposure to several air pollutants. Heavy metals from foundry emission, automobile traffics, and total suspended particulate, especially polycystic aromatic hydrocarbons have been positively linked with the development of lung cancer. Asbestos in another air pollutant with known risk of lung cancer and mesothelioma, but asbestos fibers are nonauthentic in most bioassays. Studies using the electron spin resonance spin trapping method show that the presence of iron in asbestos accelerates the production of the hydroxy, radical in vitro. Interactions of these reactive oxygen species with particular cellular components and disruption of cell defense mechanisms still await further studies to elucidate the carcinogenic potential of asbestos fibers of different size and chemical composition. The distribution of inhaled pollutants and the magnitude of their eventual effects on the respiratory tract are determined by pollutant-independent physical factors such as anatomy of the respiratory tract and level and pattern of breathing, as well as by pollutant-specific phyco-chemical factors such as the reactivity, solubility, and diffusivity of the foreign gas in mucus, blood and tissue. Many of these individual factors determining dose can be quantified in vitro. However, mathematical models based on these factors should be validated for its integrity by using data from intact human lungs.

• 한국축산식품학회지
• /
• 제37권6호
• /
• pp.940-947
• /
• 2017

Goat milk has a protein composition similar to that of breast milk and contains abundant nutrients, but its use in functional foods is rather limited in comparison to milk from other sources. The aim of this study was to prepare a goat A2 ${\beta}$-casein fraction with improved digestibility and hypoallergenic properties. We investigated the optimal conditions for the separation of A2 ${\beta}$-casein fraction from goat milk by pH adjustment to pH 4.4 and treating the casein suspension with calcium chloride (0.05 M for 1 h at $25^{\circ}C$). Selective reduction of ${\beta}$- lactoglobulin and ${\alpha}_s$-casein was confirmed using sodium dodecyl sulphate-polyacrylamide gel electrophoresis and reverse-phase high-performance liquid chromatography. The hypoallergenic property of A2 ${\beta}$-casein fraction was examined by measuring the release of histamine and tumor necrosis factor alpha from HMC-1 human mast cells exposed to different proteins, including A2 ${\beta}$-casein fraction. There was no significant difference in levels of both indicators between A2 ${\beta}$-casein treatment and the control (no protein treatment). The A2 ${\beta}$-casein fraction is abundant in essential amino acids, especially, branched-chain amino acids (leucine, valine, and isoleucine). The physicochemical properties of A2 ${\beta}$-casein fraction, including protein solubility and viscosity, are similar to those of bovine whole casein which is widely used as a protein source in various foods. Therefore, the goat A2 ${\beta}$-casein fraction may be useful as a food material with good digestibility and hypoallergenic properties for infants, the elderly, and people with metabolic disorders.

• 한국입자에어로졸학회지
• /
• 제15권4호
• /
• pp.191-202
• /
• 2019

In this study, performance (particle removal efficiency and breathing resistance) of several commercially available face masks (electrostatic filter masks (KF80 certified), a nanofiber filter mask (KF80 certified), and an uncertified mask) with their filter structure and composition were evaluated. Also, effects of relative humidity (RH) of incoming air, water and alcohol exposure, and reusability on performance of face masks were examined. Monodisperse and polydisperse sodium chloride particles were used as test aerosols. Except the uncertified mask filter, PM_2.5 removal efficiency was found to be higher than 90%, and the nanofiber filter mask had the highest quality factor due to the low pressure drop and high removal efficiency (nanofibers were arranged in a densely packed pore structure and contained a significant amount of fluorine in addition to carbon and oxygen). In the case of the KF80 certified mask, the removal efficiency was little affected when the RH of incoming air increased. When the mask filters were soaked in water, the removal efficiency of mask filters was degraded. In particular, the uncertified mask filter showed the highest removal efficiency degradation (26%). When the mask was soaked in alcohol, the removal efficiency also decreased with the greater degree than the water soaking case. The nanofiber mask filter showed the strongest resistance to alcohol exposure among tested mask filters. During evaluation of reusability of masks in real life, the removal efficiency of certified mask filter was less than 4% for 5 consecutive days (2 hours per day), while the removal efficiency of uncertified mask filter significantly decreased by 30% after 5 days.

• 한국수산과학회지
• /
• 제7권4호
• /
• pp.209-214
• /
• 1974

Casein을 단백원으로 하고 조단백질과 지질의 함량을 조사한 사료로서 치무지개송어를 19일간 사육하여 다음과 같은 결과를 얻었다. 1) 무지개송어의 체중은 사료중의 단백질 함량이 많을수록 증가하며 단백질의 함량 $40\%$ 부근에서 최대치에 달하고 그 이상 단백질이 증가하여도 체중은 증가하지 않았다. 체단백질의 증가도 사료중의 단백질 함량이 $40\%$ 부근에서 최대치에 가까워지며 그 이상 단백질이 증가하여 도 변화는 적었다. 2) 단백질의 이용치는 사료중의 단백질 함양이 많을 수록 증가하였으나 체단백질의 축적률은 단백질의 함량 $40\%$ 부근에서 최대치에 달했다. 3) 이상의 결과에서 Casein을 단백원으로 하는 경우 치무지개송어의 단백질 요구량은 사료중 $40\%$라고 생각했다. 4) 사료의 단백효율(y)은 단백질의 함양(x)이 많을 수록 감소하고 그 관계는 y=4.91-0.034x의 방정식으로 표시 할 수 있었다. 5) 사료의 단백질 함량과 사료효율 및 사료계수와의 관계를 검토하였다. 끝으로 시종 실험을 지도하여 주신 동경수산대학에 야진길 교수에게 사의를 표한다.

• 대한한의학원전학회지
• /
• 제24권4호
• /
• pp.43-53
• /
• 2011

According to the result about 'San Jiao(三焦)'recorded on "Yellow Empero's Canon Internal Medicine Ling Shu(黃帝內經 靈樞)", we achieved following results. 1. As we consider the concept of 'San Jiao' recorded on "Ling Shu", in early time, it was related to bladder(膀胱) and there was no divided concept into 'Shang Jiao(上焦)', 'Zhong Jiao(中焦)' and 'Xia Jiao(下焦)'. Later, there was appearance of body metabolism concept in anatomic way and started to emphasize that stomach(胃) is the very beginning of digestion. This point then adjusted into the concept which the core theory of digestion and water metabolism begins with 'Zhong Jiao' and processes to 'Shang Jiao' and 'Xia Jiao' then it established the 'San Jiao' theory adjusted to the functional change than property change. Later as there is set theoretical structure of 'three Yin and three Yang(三陰三陽)', it included the concept of 'San Jiao' onto meridian system theory to complete as a theory. Finally, it completed the theoretical structure that 'San Jiao' runs water metabolism of circulation, body fluid and urine for body to produce blood and Qi to protect and provide nutrition to the human body. 2. From the point of each part, 'San Jiao' means all body composition factor related to the relation to the digestion and water metabolism to produce Qi and blood. Also, the details of entire function of 'San Jiao' tells that 'Zhong Jiao' intakes food and divides the clarity and turbidity of digested substances. The origin of this digestion and water metabolism lies at Xia Jiao. The clean substance including the mood and taste climbs via Shang Jiao. The vapor like substance climbed to Shang Jiao becomes 'defensive Qi(衛氣)' and controls body temperature and sweat by supporting and spreading the Qi by Shang Jiao. The liquid substance climbed to Shang Jiao becomes blood. The blood has stronger character as substance than defensive Qi so Zhong Jiao becomes the base and the way for the blood. The turbid Qi separated at Zhong Jiao passes large intestine and the solid substance is excreted and the liquid is absorbed into bladder. The Xia Jiao that controls this process controls the liquid state of water matabolism so control the urine with bladder. Therefore, 'San Jiao' can be understood as a general concept that controls entire water metabolism as a way of food, Qi and blood.

• 한국산림과학회지
• /
• 제88권2호
• /
• pp.179-184
• /
• 1999

이 연구는 강원도 평창군 내 국유림의 활엽수 천연림 지역을 대상으로 하여 산림 작업에 의해 변화된 서식지 구조에 따른 소형 포유류 개체군의 차이를 파악하고자 1996년 5월에서 11월까지의 기간 동안 조사를 실시하였다. 소형포유류를 4주 간격으로 생체포획용 덫을 사용하여 7회에 걸쳐 포획-재포획 법을 통해 포획을 실시하였다. 조사지역에서는 흰넓적다리붉은쥐(45.1%, n=64)와 대륙밭쥐(54.9%, n=78)의 2종이 포획되었는데, 흰넓적다리붉은쥐는 벌채지와 비벌채지에서, 대륙밭쥐는 간벌지와 비벌채지에서 각각 포획되었다. 월별 포획된 소형 포유류의 개체수를 비교한 결과 비벌채지에서 가장 높았으며, 벌채지에서 가장 낮은 것으로 나타났다. 또한 월별 포획된 지역별 개체군의 동태 역시 같은 경향을 나타내었다. 조사지역별로 성숙 개체들의 체중에 차이가 있는 것으로 나타났는데 흰넓적다리붉은쥐의 경우 벌채지보다 비벌채지에서, 대륙밭쥐의 경우 간벌지보다 비벌채지에서 포획된 개체들의 체중이 무거운 것으로 나타났다. 서식지 구조에 따라 소형 포유류 개체군의 차이가 있는 것으로 나타났는데 이를 통해 서식지의 산림환경구조가 소형 포유류의 종 구성 및 서식에 큰 영향을 미치는 것으로 판단된다.

• Nutrition Research and Practice
• /
• 제6권3호
• /
• pp.226-231
• /
• 2012

The purpose of the study was to assess the effects of a 12 weeks aged garlic extract (AGE) regimen with regular exercise on cardiovascular disease (CVD) risk in postmenopausal women. A total of 30 postmenopausal women ($54.4{\pm}5.4$ years) were randomly divided into the following four groups: Placebo (Placebo; n = 6), AGE intake (AGEI; n = 8), exercise and placebo (Ex + Placebo; n = 8), exercise and AGE (Ex + AGE; n = 8) groups. The AGE group consume 80 mg per day, and exercise groups performed moderate exercise (aerobic and resistance) three times per week. After 12 weeks of treatment, body composition, lipid profile, and CVD risk factors were analyzed. Body weight was significantly decreased in AGEI, Ex + Placebo, and Ex + AGE groups compared to baseline. Body fat % was significantly decreased in the AGEI and Ex + Placebo groups. Body mass index (BMI) was significantly decreased in the AGEI, Ex + Placebo, and Ex + AGE groups. Fat-free mass was significantly decreased in the AGEI group. Total cholesterol (TC) was significantly lower in the Ex + Placebo compared to the Placebo group. AGE supplementation or exercise effectively reduced low-density lipoprotein (LDL-C). Triglyceride (TG) was significantly increased in the AGEI group. Malondialdehyde (MDA) levels were significantly decreased in the AGEI, Ex + Placebo, and Ex + AGE compared to the placebo group. AGE supplementation reduced homocysteine levels regardless of whether the women also exercised. The present results suggest that AGE supplementation reduces cardiovascular risk factors independently of exercise in postmenopausal women.

• 생물정신의학
• /
• 제20권4호
• /
• pp.144-150
• /
• 2013

Objectives The number of marriage immigrant women has been increasing in the past several years in Korea and their adaptations to the new environment have been an important social issue. The aims of this study were to evaluate the psychosocial and mental health statuses of Vietnamese marriage immigrant women (VMIW). We intended to compare the mental health of VMIW with married Vietnamese women living in Vietnam and reveal the demographic or psychosocial factors affecting their mental health. Method Subjects comprised one-hundred-forty-three VMIW who enrolled in multiculture family support centers in Chungbuk Province and forty-eight women from Vinh Phuc province in Vietnam. Marital satisfaction, domestic violence and social support were evaluated as psychosocial factors, and the Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI) and General Health Questionnaire (GHQ) were used to evaluate mental health. Results VMIW had a larger age gap with their husbands but better psychosocial statuses. BDI (p = 0.20), BAI (p = 0.08), GHQ (p = 0.13) scores of VMIW were not significantly different compared to Vietnamese residents. Marriage duration of VMIW affects significantly their marital satisfaction, social support and depressive levels (p < 0.01). The level of domestic violence showed a significant difference according to the educational levels of their husbands, composition of family members and marriage process (p < 0.05). VMIW with older husbands and jobless VMIW had low levels of anxiety (p < 0.01). Conclusion The results suggest that VMIW have no difference in mental health compared to Vietnamese women living in Vietnam which is contrary to general expectations. However, various environmental factors, such as marriage duration, have an effect on the mental health of VMIW. As marriage duration is proven to be important factor on mental health of VMIW, more extended duration of care and interventions are needed to maintain good mental health. Networking system connecting mental health screenings by the multiculture family support center to the local mental healthcare center is needed to care those with poor screening outcomes.

• 한국습지학회지
• /
• 제19권2호
• /
• pp.223-229
• /
• 2017

본 연구는 동림저수지에서 지난 18년(1999~2016)동안 1월에 조사한 조류자료를 대상으로 시계열적 변화와 환경 요인과의 관계에 대해 분석하였다. 조사 자료는 '겨울철 조류 동시센서스'를 활용하였고, 연도별 개체군의 변화를 파악하기 위해 주성분 분석과 군집분석을 사용하였다. 환경 요인은 1월 평균 기온과 평균 저수율을 이용하였다. 연구 결과, 조류의 개체군 변화는 2개의 물새 그룹과 산새 그룹 1개의 증감으로 설명될 수 있다. 물새 그룹의 개체수가 증가하는 시기는 산새 그룹의 개체수가 증가하는 시기에 비해 월평균기온이 $1.4^{\circ}C$ 이상 높았다. 이에 비해 저수율의 영향은 분명하지 않았다. 기온의 영향을 받는 가창오리의 도래 여부는 나머지 하나의 물새 그룹과 산새 그룹에 모두 영향을 주는 요인이었다. 이 연구 결과는 기온 변화가 조류의 광역적인 공간 분포에 영향을 미치고, 가창오리와 같이 개체군이 큰 종 또는 무리의 이동은 조류의 지역적인 종구성과 개체수에 영향을 미친다는 것을 시사한다. 따라서 광역적인 규모에서의 환경 변화와 그에 따른 종 분포의 변화에 대한 이해는 지역적인 규모에서 조류 개체군의 시계열적 흐름을 이해하는데 도움을 준다.

• 한국재료학회지
• /
• 제30권10호
• /
• pp.566-572
• /
• 2020

In the recent years, thin film solar cells (TFSCs) have emerged as a viable replacement for crystalline silicon solar cells and offer a variety of choices, particularly in terms of synthesis processes and substrates (rigid or flexible, metal or insulator). Among the thin-film absorber materials, SnS has great potential for the manufacturing of low-cost TFSCs due to its suitable optical and electrical properties, non-toxic nature, and earth abundancy. However, the efficiency of SnS-based solar cells is found to be in the range of 1 ~ 4 % and remains far below those of CdTe-, CIGS-, and CZTSSe-based TFSCs. Aside from the improvement in the physical properties of absorber layer, enormous efforts have been focused on the development of suitable buffer layer for SnS-based solar cells. Herein, we investigate the device performance of SnS-based TFSCs by introducing double buffer layers, in which CdS is applied as first buffer layer and ZnMgO films is employed as second buffer layer. The effect of the composition ratio (Mg/(Mg+Zn)) of RF sputtered ZnMgO films on the device performance is studied. The structural and optical properties of ZnMgO films with various Mg/(Mg+Zn) ratios are also analyzed systemically. The fabricated SnS-based TFSCs with device structure of SLG/Mo/SnS/CdS/ZnMgO/AZO/Al exhibit a highest cell efficiency of 1.84 % along with open-circuit voltage of 0.302 V, short-circuit current density of 13.55 mA cm^-2, and fill factor of 0.45 with an optimum Mg/(Mg + Zn) ratio of 0.02.