• Archives of Plastic Surgery
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• 제42권2호
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• pp.173-178
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• 2015

Background Various focal heating devices are popular in Korea under the cultural influence of the traditional ondol under-floor method of home heating. These devices can cause severe burn-like injuries resulting from device malfunction or extended with low heat contact. In addition to injuries under these high heat contact, burns can be occurred by low heat exposure with prolonged periods despite the devices are properly functioning. In order to develop strategies to reduce the duration of periods of illness due to low-temperature burns, we analyzed and compared treatment methods and therapeutic periods for this type of injury. Methods This retrospective study included 43 patients burned under low heat conditions. Patients were divided into an operative group and a conservative group. The patients in the operative group underwent at least one surgical excision, and were further subdivided into early and late visit groups. The conservative group was treated only with dressings. We compared the treatment periods between the operative group and the conservative group, and also compared the preparation periods and treatment periods between the two operative groups. Results The average treatment period was significantly shorter in the operative group (P=0.02). In the early visit operative group, both wound preparation and treatment were briefer than in the late visit group. Conclusions We recommend that early proper burn care and early surgical intervention, including appropriate excision, are feasible ways to reduce the treatment period of lowtemperature burn patients.

• Safety and Health at Work
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• 제12권1호
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• pp.74-95
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• 2021

Background: A job-exposure matrix (JEM) is an important surrogate indicator to evaluate past exposure levels. Although a Korean asbestos JEM has been constructed previously, this JEM includes only a few industrial and occupational groups. This study aimed to reconstruct the JEM by integrating the latest organized data to improve its utility. Methods: We used recent Korean standard industry and occupation codes and extracted 36 articles from a systematic literature review to initiate the reconstruction of the previous Korean asbestos JEM. The resulting data consisted of 141 combinations of industrial and occupational groups. Data from the Netherlands's JEM were also reviewed and categorized into 70 industrial and 117 occupational groups by matching with the Korean data. We also utilized Germany's data, which consisted of 10 industrial and 14 occupational groups. Results: The reconstructed Korean asbestos JEM had 141 combinations of industries and occupations. The time periods are from the 1980s to the 2000s in 10-year intervals. Most of the data were distributed between the 1990s and the 2000s. Occupations with high exposure to asbestos included knitting and weaving machine operators, automobile mechanics or assemblers, ship mechanics or assemblers, mineral ore and stone products processing mechanics, and metal casting machine operators or mold makers. Conclusions: The reconstructed Korean asbestos JEM has expanded the type and duration of the occupational groups of the previous JEM and can serve as an important reference tool for evaluating asbestos exposure and designing compensation and prevention policies in Korea.

• Journal of Radiation Protection and Research
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• 제35권2호
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• pp.57-62
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• 2010

원전 계획예방정비기간 증기발생기 수실작업, 가압기 전열관교체 또는 압력관피더 제거작업 지역 등은 높은 방사선량률을 보이는 지역으로, 짧은 시간 동안의 작업으로 작업종사자는 높은 피폭을 받을 가능성이 있다. 특히, 방사성물질과 접촉하는 손 부위는 높은 피폭이 일어날 수 있다. 이런 점을 고려하여 국내 가압경수로원전과 가압중수로원전의 계획 예방정비기간 중 증기발생기 수실 노즐댐 설치와 제거작업, 원자로 냉각재펌프 보수작업, 원자로헤드 보수 및 검사작업 등과 같은 고피폭 접촉작업에서 방사선작업종사자의 말단선량을 측정하기위한 현장시험을 실시하였다. 여기에 참여한 작업종사자는 가슴과 등 부위에 일상적인 절차에 따른 복수선량계를 패용한 것 이외에 손목에 개인선량계를 추가로 패용하였고, 손가락 부위에는 말단선량계 (Extremity dosimeter)를 패용하였다. 그 결과, 손가락이 받는 등가선량은 각각 손목이 받는 등가선량 및 가슴 또는 등 부위가 받는 등가선량과 일정한 비율로 평가됨을 확인하였다.

• 한국초지조사료학회지
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• 제14권2호
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• pp.132-141
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• 1994

본 시험은 reed canarygrass silage의 품질을 향상시키고 호기적 변패를 방지시킬 목적으로 재료를 약 1.5cm 길이로 절단하여 formic acid, caproic acid 및 두가지 산을 혼합하여 첨가한 silage를 9개의 처리구로 나누어 실험용 silo에 제조하였으며, silage의 품질분석을 위해서 두께 0.1mm, 용량 50kg의 vinyl bag을 이용하였다. 또한 호기적 상태에서의 온도변화, 질소 함량 변화 및 변패방지를 위한 silage의 안정성 시험은 지름 25cm$\times$높이 30cm의 plastic용기를 이용하여 개봉 직후와 7일간의 호기적 조건에서 실시한 결과를 요약하면 다음과 같다. 2. Silage의 화학적 조성에서 개봉 직후의 조단백질과 NFE함량은 formic acid와 caproic acid를 혼합 첨가함으로서 높았으며(P<0.01), 7일간의 호기적 상태에서는 혼합 첨가를 함으로서 조섬유와 ADF함량이 낮게 나타났다.(PM0.01). 2. Silage의 온도변화는 formic acid를 첨가함으로서 개봉 2일에 최고온도($34.4^{\circ}C$)에 도달했으며, caproic acid의 첨가와 formic acid + caproic acid의 혼합첨가를 함으로서 온도상승을 방지할 수 있었다. 3. 호기적 상태에서 silage의 pH변화는 formic acid를 첨가할 경우에는 효과가 없었으나, caproic acid를 첨가함으로서 silage의 pH는 안정되었다. 4. 총 질소에 대한 암모니아태 질소의 함량비율은 formic acid첨가구>caproic acid 첨가구>혼합첨가구 순으로 유의적으로 나타났다(P<0.01) 5. Caproic acid 1.2%첨가와 formic acid의 혼합 첨가(1.2%+1.2%)를 함으로서 mould의 성장을 억제하는 효과가 크게 나타났다.

• 한국산업보건학회지
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• 제21권1호
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• pp.11-24
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• 2011

Working in a research laboratory means exposure to a wide range of hazardous substances. Several studies indicated that laboratory workers, especially working with chemicals, might have an increased risk of certain cancers. However, exposure assessment data in laboratory settings are scarce. This study was performed to examine several approaches for quantitatively assessing the exposure levels to volatile organic compounds (VOCs) among workers in chemistry laboratories. The list of 10 target VOCs, including ethanol, acetone, 2-propanol, dichlormethane, tetrahydrofuran, benzene, toluene, n-hexane, ethyl acetate, chloroform, was determined through self-administered questionnaire for six chemistry research laboratories in a university, a government-funded research institute, or private labs. From September to December 2008, 84 air samples were collected (15 area samples, 27 personal time weighted samples, 42 personal task-basis short-term samples). Real time monitors with photo ionization detector were placed during the sampling periods. In this study, benzene was observed exceeding the action levels, although all the results were below the American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV). From the air sampling results, we concluded that (1) chemicals emitted during experiments could directly affect to neighbor office areas (2) chemical exposures in research laboratories showed a wide range of concentrations depending on research activities (3) area samples tended to underestimate the exposures relative to personal samples. Still, further investigation, is necessary for developing exposure assessment strategies specific to laboratories with unique exposure profiles.

• Asian-Australasian Journal of Animal Sciences
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• 제7권3호
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• pp.357-362
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• 1994

Five adult sheep were exposed to intermittent cold for 12 h (18:00-06:00) at an air temperature of $5{\pm}1^{\circ}C$ followed by 12 h (06:00-18:00) at $25{\pm}2^{\circ}C$ over a period of 8 days continuously. Carotid artery blood (Tc), mean skin (Ts) and mean body (Tb = 0.86 Tc + 0.14 Ts) temperatures, heat production rate (HP), respiratory evaporative heat loss, respiration rate (RR) and volume were measured before and after exposure. Tc during the 12 h cold period of intermittent cold exposure was similar to that during the corresponding period in the warm environment, while Tc in the $25^{\circ}C$ of intermittent cold was higher (p < 0.05) than that in the corresponding period in the warm environment. Ts during the cold period markedly decreased (p < 0.001) by about $9^{\circ}C$ when compared with that in the corresponding time period in the warm environment, while Ts during the $25^{\circ}C$ period of intermittent cold recovered to a similar level to that in the warm environment. Tb was lower (p < 0.001) during the cold period of intermittent cold, whereas a slight increase in Tb during the $25^{\circ}C$ period of intermittent cold was significant (p < 0.05) when compared with the value during the similar period in the warm environment. HP was greatly increased (p < 0.001) by cold exposure, followed by an immediate decrease during the first one hour of the 12 h warm period, reaching a similar level to that in the warm environment. A lower (p < 0.05) RR was observed during both the cold and $25^{\circ}C$ period of intermittent cold than during the corresponding periods in the warm environment. The results of the present investigation clearly show that the body temperature of sheep increased during a 12 h warm period following 12 h of exposure to cold. These results suggest that during a warm period of an intermittent cold exposure cycle, heat could be shored in the animal body.

• 환경생물
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• 제22권2호
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• pp.321-328
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• 2004

The effects of Di (2-ethylhexyl) phthalate (DEHP) on the fourth instar larvae of Chironomus riparius were tested in the laboratory. Employing a waterreplacement exposure setup, chironomids were subjected to various concentrations. In the most treatments mortality reached a statistically significant difference from the control conditions. As DEHP concentrations were increased, the rates of emerged adults decreased. Sex ratio was unaffected with little deviation from a 1:1 relationship (except in 1 and $30\mu{g}\;L^{-1})$. The developmental stages was delayed at low concentration (0.3 and $1\mu{g}\;L^{-1})$. Generally the emergent period was different between males and females, and the first emergent day of males was faster than females. The body shape of female adults was larger than males. Differences between males and females were found in body volume, body length and body width. In addition, the body volume showed the significant difference between controls and treatments, and those especially well observed females.

• 한국응용곤충학회지
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• 제17권1호
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• pp.71-73
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• 1978

수출 볏짚 제품내에 들어있는 월도 이화명충을 방제하기 위하여 Phostoxin $30\%$ 훈증제를 $27^{\circ}C$ 기온상태에서 $1m^3$들이 프라스틱 chamber를 사용하여 농도 및 처리시간을 달리하여 시험한 결과 다음과 같은 결과를 얻었다. 1. 월동유충은 처리 48시간, 옹은 24시간, 성충은 8시간에서 $100\%$의 살충율 얻었다. 2. 약제의 사용농도 보다는 처리시간의 장단에 따라서 살충효과의 차이가 있었다.

• 생태와환경
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• 제56권4호
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• pp.406-413
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• 2023

어류의 시각적 및 화학적 정보를 토대로 포식자를 인지하는 능력은 개체가 자연에서 생활하는 동안 학습을 통해서 확보된다. 하지만 인공증식된 멸종위기종들의 경우 자연적응력 부족으로 인한 복원효율성 저하가 지속적으로 발생하고 있다. 따라서 본 연구에서는 복원을 위해 인공증식된 멸종위기종 여울마자의 자연적응력 증진을 위해 포식자 인지 능력 증진을 수행하였다. 연구결과 포식자 인지 훈련 기간에 따라 자극원에 대한 반응성이 달라짐을 확인할 수 있었으며, 인공증식된 여울마자는 동종의 알람신호를 통해 위험을 인지하는 능력이 떨어져 있었으며, 이는 포식 위험원 노출을 통한 훈련으로 개선이 가능하였고, 포식자에 노출되었을 때 포식자와 알람신호에 동시에 노출 되었을 경우 훈련 기간이 길어짐에 따라 자극에 대한 반응성이 줄어드는 것을 확인하였다. 알람신호에 대한 반응은 시간이 지날수록 커지는 경향을, 포식자에 대한 반응은 훈련 48시간 후 가장 높은 반응을 보이고 72시간 후 반응성이 떨어지는 경향을, 알람신호와 포식자 동시 노출에 대한 반응은 훈련 이전 가장 높은 반응을 보인 뒤 반응성이 낮아진 채로 유지되는 경향을 보였다. 따라서 방류 전 인공증식 개체의 동종의 알람신호(화학적 자극)에 대한 반응성을 높이기 위한 프로그램이 필요하며, 포식자(시각적 자극)에 대한 반응성도 높게 나타난 48시간가량의 포식 위험원 노출이 적합하다고 판단된다. 본 실험을 통해 인공증식 여울마자의 동족 알람신호 자극에 대한 반응성 부족이 확인되었으며 멸종위기종 방류전 자연성 증진 프로그램의 운용의 필요성이 확인되었다.

• Preventive Nutrition and Food Science
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• 제6권1호
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• pp.1-5
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• 2001

Pigment extracts obtained from Star Ruby grapefruit pulp were stored at different temperatures (4.5$^{\circ}C$, 23$^{\circ}C$) and exposed to light. many carotenoid oxidation products were formed due to light-exposure during storage periods. They were monitored by using HPLC with photodiode array detection and tentatively identified. Including (all-E)-lycopene and trans-$\beta$-carotene as predominant carotenoids in red grapefruit, 5Z-lycopene, 9Z-lycopene, 13Z-lycopene, and 15-cis-$\beta$-carotene were formed at 4.5$^{\circ}C$, 23$^{\circ}C$. Degradation of all-tarns lycopene was more susceptible to light-exposure and temperature a than that of all-trans $\beta$-carotene. The formation of lycopene cis isomers was favored under lighted condition. Respectively, (5Z)-lycopene was formed in greater amounts than other isomers at 23$^{\circ}C$ storage. The concentration of 15-cis-$\beta$-carotene was significantly increased during storage at 23$^{\circ}C$ storage. The concentration of 15-cis-$\beta$-carotene was significantly increased during storage at 23$^{\circ}C$.