• Safety and Health at Work
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• 제10권2호
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• pp.219-223
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• 2019

Background: Ice cooling vests can cause tissue damage and have no flexibility. Therefore, these two undesirable properties of ice cooling vest were optimized, and the present study was aimed to compare the impact of the optimized ice cooling vest and a commercial paraffin cooling vest on physiological and perceptual strain under controlled conditions. Methods: For optimizing, hydrogel was used to increase the flexibility and a layer of the ethylene vinyl acetate foam was placed into the inside layer of packs to prevent tissue damage. Then, 15 men with an optimized ice cooling vest, with a commercial paraffin cooling vest, and without a cooling vest performed tests including exercise on a treadmill (speed of 2.8 km/hr and slope of %0) under hot ($40^{\circ}C$) and dry (40 %) condition for 60 min. The physiological strain index and skin temperature were measured every 5 and 15 minutes, respectively. The heat strain score index and perceptual strain index were also assessed every 15 minutes. Results: The mean values of the physiological and perceptual indices differed significantly between exercise with and without cooling vests (P < 0.05). However, the difference of the mean values of the indices except the value of the skin temperature during the exercises with the commercial paraffin cooling vest and the optimized ice cooling vest was not significant (P > 0.05). Conclusions: The optimized ice cooling vest was as effective as the commercial paraffin cooling vest to control the thermal strain. However, ice has a greater latent heat and less production cost.

• 인간식물환경학회지
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• 제24권6호
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• pp.639-649
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• 2021

Background and objective: Various images from visual display terminals (VDTs) as well as living lighting are important parts of our daily life; thus, properly controlling the lighting environment - that is, illuminance, color temperature and good images from VDTs - can have a substantial effect on improving the mental health and work efficiency in everyday life. We examined electroencephalography (EEG) and heart rate variability (HRV) responses to various lighting conditions in 25 university students as they viewed images of a green landscape or traffic congestion. Methods: EEG was performed in darkness and when the room was illuminated with 10 different light-emitting diode (LED) color temperatures, while the EEG and HRV responses to green landscape or traffic congestion image stimuli were measured in darkness and during room illumination with three different LED color temperatures. Results: We found a significant difference between darkness and high LED illumination (400 lx) at 7 (CZ, F4, FZ, O1, O2, OZ, and T6) of 30 channels, while the alpha wave activity increased during darkness. In the second experiment, the green landscape image stimuli in the 30 lx-2600 K lighting condition elicited theta wave activity on the EEG, whereas the traffic congestion image stimuli under high LED illumination elicited high beta and gamma wave activities. Moreover, the subjects exhibited better stress coping ability and heart rate stability in response to green landscape image stimuli under illuminated conditions, according to their HRV. Conclusion: These results suggest that lower color temperatures and illumination levels alleviate tension, and that viewing green landscape image stimuli at low illumination, or in darkness, is effective for reducing stress. Conversely, high illumination levels and color temperatures are likely to increase tension and stress in response to traffic congestion image stimuli.

• 전자공학회논문지SC
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• 제49권3호
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• pp.53-61
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• 2012

본 논문에서는 스테레오 적외선 카메라를 이용하여 소형 및 고온으로 날아가는 이동체의 거리를 실시간으로 측정하는 시스템을 제안한다. 이동체와 주변 환경의 온도 차이를 측정하고 고속으로 이동하는 소형 이동체의 거리를 자동으로 측정하기 위하여 적외선 스테레오 카메라 시스템을 구축하였다. 우선 적외선 카메라를 이용하여 취득한 고온의 이동체 영상으로부터 주변의 온도분포와 이동체간의 온도차를 이용하여 이동체영역을 검출하고, 이동체의 움직임 정보와 적외선 카메라 영상의 밝기정보를 결합하여 이동체를 추적한다. 좌우 적외선 카메라 영상에 대하여 각각 추출된 이동체 영역을 중심으로 스테레오 정합을 수행하여 시차정보를 추정하고, 카메라 파라미터와 시차정보를 이용하여 실시간으로 이동하는 이동체의 거리를 추정한다. 본 논문에서 제안하는 적외선 스테레오 카메라 시스템을 검증하기 위하여 고온의 이동체를 촬영할 때, 3차원 궤적(x,y,z) 측정기를 함께 가동하여 이동체가 이동하는 거리를 측정하여 이를 기준 거리(ground truth)로 설정하였다. 3차례의 비디오 데이터로부터 실험한 결과, 적외선 스테레오 카메라를 이용한 고온/소형 이동체의 거리오차 측정 결과는 평균적으로 9.68%로 추정되었다. 스테레오 적외선 카메라의 타이밍 문제(jitter)를 고려하면, 실제로 추정 오차는 줄어들 것으로 판단되기 때문에, 향후 적외선 카메라를 이용하는 다양한 이동체의 거리 및 위치를 측정하는데 응용할 수 있을 것으로 기대된다.

• The Korean Journal of Pain
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• 제13권2호
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• pp.187-190
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• 2000

Background: From our clinical experience, there were some problems in paratracheal stellate ganglion block at 6th cervical level (C 6 SGB), for example, lesser change in blood flow of the upper extremity and more occurrence of hoarseness. This study was undertaken to compare the various effectiveness of C 6 SGB and paratracheal stellate ganglion block at 7th cervical level (C 7 SGB). Methods: Forty patients were equally divided into 2 groups. In the Group I, patients were undertaken C 6 SGB with 0.25% bupivacaine 6 mL and in the Group II, patients were undertaken C 7 SGB with 0.25% bupivacaine 6mL. The skin temperature of index finger was measured before and after SGB and the warm sensation on face and upper extremity, hoarseness and upper extremity paralysis were studied. Results: The skin temperature of index finger was increased significantly from $33.95{\pm}0.89^{\circ}C$ to $34.51{\pm}0.90^{\circ}C$ in the Group I and from $33.94{\pm}0.82^{\circ}C$ to $35.38{\pm}0.66^{\circ}C$ in the Group II (P<0.05) The increase of skin temperature of index finger after procedure was $0.56{\pm}0.09^{\circ}C$ in the Group I and $1.44{\pm}0.02^{\circ}C$ in the Group II. The increase of skin temperature of index finger in the Group II was more statistically significant than Group I (P<0.05). The occurance of hoarseness in the Group II was significantly less than in the Group I. There was no significant difference in warm sensation on face and upper extremity and paralysis of upper extremity in both Groups. Conclusions: C 7 SGB showed better sympathetic block effect on upper extremity than C 6 SGB and hoarseness did not occur in C 7 SGB.

• Journal of Chest Surgery
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• 제36권4호
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• pp.219-228
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• 2003

배경: 액체질소에 의한 냉동방법은 생물학과 의학에서 세포와 조직의 장기보존으로는 성공적인 방법이다. 잘 조절된 냉동속도와 해동의 방법과 함께 글라이세롤이나 디메칠설폭사이드 같은 냉동보존제의 사용으로 얼음결정이 생기는 것을 방지하여 구조의 유지와 생존율을 모두 향상시킬 수 있으며 반영구적으로 보존할 수 있다. 여러 조직의 초저온냉동에는 조직에 맞는 냉동속도가 있다. 대상 및 방법: 가장 적합한 냉동곡선과 이를 위한 냉동챔버온도를 찾기 위해서 우리들은 조직의 열역학적 계산을 두 가지 방법으로 하였다. 하나는 직접계산방법으로 모든 냉동 대상물의 열물리학적 특성, 잠재용융열, 면적, 농도와 체적을 알아야 계산할 수 있다. 이러한 방법은 매우 복잡하고 어떠한 경우에는 실제 값을 알 수 없다. 다른 방법은 간접계산방법으로 우선 기존의 냉동곡선으로 조직을 냉동시켜 조직의 실제 냉동곡선을 얻은 다음 시간상수로 냉동곡선을 분석한 다음 온도반응을 계산하고 적합한 x차방정식을 대입시켜 냉동 시 온도상승을 막고 이것을 거꾸로 냉동챔버온도를 산출하는 방식이다. 결과: 이 냉동 프로그램을 중배엽줄기세포, 연골세포와 골아세포에 적용시켜 검사하였다. 조직의 온도는 온도상승과정 없이 이상적인 냉동곡선을 따라 감소하였다. 그러나 세포의 양과 수용액의 양이 적어 냉동곡선간의 생존력이 통계학적으로 차이가 있지는 않았다. 만약 더욱 부피가 큰 조직을 냉동시키거나 프로그램을 순차적으로 계속한다면 이상곡선에 더욱 근접하게 되어 차이가 있을 것으로 판단된다. 결론： 이 프로그램은 이상적인 냉동곡선으로 조직을 냉동시키기 위한 냉동챔버온도를 쉽게 찾을 수 있도록 도움이 될 것이다.

• Journal of Yeungnam Medical Science
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• 제35권2호
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• pp.199-204
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• 2018

Background: The authors have performed ultrasound-guided stellate ganglion block (SGB) in our clinic using a lateral paracarotid approach at the level of the 6th cervical vertebra (C6). Although SGB at C6 is a convenient and safe method, there are ongoing concerns about the weak effect of sympathetic blockade in the ipsilateral upper extremity. Therefore, ultrasound-guided SGB was attempted using a lateral paracarotid approach at the level of the 7th cervical vertebra (C7). This prospective study aimed to compare changes in skin temperature after SGB was performed at C6 and C7, and to introduce a lateral paracarotid approach for SGB. Methods: Thirty patients underwent SGB twice: once at C6 and once at C7. For every SGB, the skin temperature of the patient's hypothenar area was measured for 15 min at 1-min intervals. Skin temperatures before and after SGB and side effects were compared between C6 and C7 groups. Results: The temperature of the upper extremity increased after SGB was performed at C6 and C7. There were significant differences between mean pre-SGB and the largest increases in post-SGB temperatures ($0.50{\pm}0.38^{\circ}C$ and $1.41{\pm}0.68^{\circ}C$ at C6 and C7, respectively; p<0.05). Significantly increased post-SGB temperatures (difference > $1^{\circ}C$) were found in 5/30 (16.7%) and 24/30 (80%) cases for C6 and C7, respectively (p<0.05). There were no significant differences in side effects between SGB performed at C6 or C7 (p>0.05). Conclusion: The lateral paracarotid approach using out-of-plane needle insertion for ultrasound-guided SGB performed at C7 was feasible and more effective at elevating skin temperature in the upper extremity than SGB at C6.

• Annals of Occupational and Environmental Medicine
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• 제34권
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• pp.28.1-28.12
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• 2022

Background: Haenyeo is a woman who has the job of collecting seafood in the Jeju Sea at an average temperature of 13℃-14℃. The purpose of this study was to examine the cold acclimatization and occupational characteristics of Haenyeo through biomarkers such as orexin and irisin related to heat generation in the body. Methods: Twenty-one Haenyeo and 25 people with similar age, body type, and body mass index were selected as the control group (Control G). In the cold exposure experiment, a climate chamber was set to 5℃ and both feet were immersed in a 15℃ water tank for 30 minutes. Tympanic temperature (T_ty) and skin temperature (T_sk) were measured, and the mean body temperature (mT_b) was calculated. Blood samples were collected before and immediately after the examination. Orexin and irisin levels were analyzed. Results: Orexin levels were elevated after cold stimulation from 12.17 ± 4.44 to 12.95 ± 4.53 ng/mL (Haenyeo group [Haenyeo G], p < 0.01) and 10.37 ± 3.84 to 11.25 ± 4.02 ng/mL (Control G, p < 0.001). Irisin levels were elevated after cold stimulation from 4.83 ± 2.28 to 5.36 ± 2.23 ng/mL (Haenyeo G, p < 0.001) and 3.73 ± 1.59 to 4.18 ± 2.04 ng/mL (Control G, p < 0.001). The difference between Haenyeo G and Control G values in orexin and irisin appears not only in pre-exposure but also in post-exposure (p < 0.05). Conclusions: Our experimental results suggest that Haenyeo G were relatively superior in cold tolerance to Control G under cold exposure conditions. Haenyeo's cold acclimatization is due to the basic differences in pyrogens regarding body temperature control such as orexin and irisin. This means that Haenyeo are advantageous for cold survival.

• 핵의학기술
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• 제13권1호
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• pp.116-119
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• 2009

목적: 호르몬검사에서 채혈 후, 신속한 혈장분리의 과정은 검사결과의 신뢰성에 영향을 줄 수 있다. 혈중의 Adreno Corticotropic Hormone (ACTH)은 단백질의 분해에 의해 매우 불안정한 것으로 알려져 있다. 본 연구는 ACTH검사에서 ethylenediaminetetra-acetic acid (EDTA) tube의 온도가 환자 결과에 미치는 영향과 전혈에서 시간과 온도에 따른 ACTH의 안정성을 평가하였다. 방법: 전체 22명의 검체를 대상으로 하였으며, 냉장상태의 EDTA tube와 실온상태의 EDTA tube에 채혈한 후(n=18), 즉시 원심분리하여 두 그룹 간의 ACTH 결과를 비교하였다. 전혈상태의 EDTA 검체를 일정량을 나누어 분주하여, 실온에서 2시간(n=11), 4시간(n=11), 24시간(n=7), 냉장에서 24시간(n=7) 동안 방치한 후 원심분리하여 ACTH 농도를 측정하였다. 냉장 EDTA에 채혈 후 즉시 원심분리된 검체의 ACTH 결과와 실온에서 2시간, 4시간 방치된 검체의 ACTH결과를 비교하였고, 냉장에서 24시간 방치된 결과와 실온에서 24시간 방치된 결과를 비교하였다. 통계적인 분석은 paired t-test를 이용하였다. 결과: 실온상태의 EDTA tube에 채혈한 ACTH 결과가 냉장상태의 EDTA tube에 채혈한 결과보다 유의하게 낮게 나타났다(p=0.018). 채혈 후 즉시 원심분리된 ACTH 결과와 비교하여 실온에서 2시간 방치된 결과가 유의하게 낮았고 (p<0.001), 실온 2시간과 실온 4시간 사이에는 유의한 차가 없었다(p=0.907). 24시간 동안 방치된 결과를 보면, 실온보관과 냉장보관에서 유의한 차가 없었다(p=0.474). 결론: ACTH 검사 시에는 냉장고에 넣어둔 EDTA tube의 사용이 권장되며, 채혈 후 2시간 동안 실온에서 방치될 경우 결과가 유의하게 감소되므로, 신속한 원심분리가 요구된다.

• Journal of Acupuncture Research
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• 제27권1호
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• pp.117-127
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• 2010

Background : To demonstrate the efficacy of moxibustion therapy, randomized controled trials are required. But, clinical trials of moxibustion had limitations due to the absence of a sham moxibustion model for an appropriate placebo. Objectives : To develop a new sham moxibustion model based on the thermal characteristics of commercial indirect moxibustion, especially temperature, and to evaluate whether it could be applied in clinical trials. Methods : By applying heat insulation, we created a sham moxibustion device that was indistinguishable from a real one with the naked eye. It also stimulated heat but had inert remedial value. A clinical trial was performed on subjects to test double blinding. The subjects were randomly assigned into two groups, a treatment group and a sham group. Acupoint Zusanli($ST_{36}$) was used in each group for 3 times. A sham acupuncture credibility questionnaire was modified into a moxibustion credibility questionnaire and was filled out after treatment. Results : No major difference was detected in the subjects' baseline data. Most subjects and practitioners could not distinguish the sham moxibustion device from the real one. But, subjects who had experience of moxibustion therapy more likely to distinguish the sham moxibustion device from the real one than subjects who didn't have experience of moxibustion therapy. The treatment group showed a significant difference in the VAS(Visual Analog Scale) for intensity of sensation during treatment than that of the sham group. Conclusions : The sham moxibustion device in this study is proved sufficient and credible to be applied in investigations of the effect of moxibustion. But it is more appropriate for the people who don't have experience of moxibustion therapy.

• Journal of Ecology and Environment
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• 제42권4호
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• pp.272-277
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• 2018

Background: Studying the ecosystem carbon cycle requires analysis of interrelationships between soil respiration (Rs) and the environment to evaluate the balance. Various methods and instruments have been used to measure Rs. The closed chamber method, which is currently widely used to determine Rs, creates a closed space on the soil surface, measures $CO_2$ concentration in the inner space, and calculates Rs from the increase. Accordingly, the method is divided into automatic or manual chamber methods (ACM and MCM, respectively). However, errors of these methods and differences in instruments are unclear. Therefore, we evaluated the characteristics and difference of Rs values calculated using both methods with actual data. Results: Both methods determined seasonal variation patterns of Rs, reflecting overall changes in soil temperature (Ts). ACM clearly showed detailed changes in Rs, but MCM did not, because such small changes are unknown as Rs values are collected monthly. Additionally, Rs measured using MCM was higher than that using ACM and differed depending on measured plots, but showed similar tendencies with all measurement times and plots. Contrastingly, MCM Rs values in August for plot 4 were very high compared with ACM Rs values because of soil disturbances that easily occur during MCM measurements. Comparing Rs values calculated using monthly means with those calculated using MCM, the ACM calculated values for monthly averages were higher or lower than those of similar measurement times using the MCM. The difference between the ACM and MCM was attributed to greater or lesser differences. These Rs values estimated the carbon released into the atmosphere during measurement periods to be approximately 57% higher with MCM than with ACM, at 5.1 and $7.9C\;ton\;ha^{-1}$, respectively. Conclusion: ACM calculated average values based on various Rs values as high and low for measurement periods, but the MCM produced only specific values for measurement times as representative values. Therefore, MCM may exhibit large errors in selection differences during Rs measurements. Therefore, to reduce this error using MCM, the time and frequency of measurement should be set to obtain Rs under various environmental conditions. Contrastingly, the MCM measurement is obtained during $CO_2$ evaluation in the soil owing to soil disturbance caused by measuring equipment, so close attention should be paid to measurements. This is because the measurement process is disturbed by high $CO_2$ soil concentration, and even small soil disturbances could release high levels into the chamber, causing large Rs errors. Therefore, the MCM should be adequately mastered before using the device to measure Rs.