• 한국산업보건학회지
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• 제19권4호
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• pp.403-411
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• 2009

This study was performed to propose appropriate conditions suited to the analysis of naphthalene by comparing desorption efficiencies under various conditions. 1. As to influence by adsorbing media and desorbing solvent on desorption efficiency of naphthalene, when adsorbed by CCT, o-xylene gave the highest desorption efficiency of $73.96{\pm}0.53%$ while the lowest of $1.14{\pm}0.03%$ desorbed by ether. Both XAD-2 and Chromosorb 106 showed around 90% of desorption efficiencies for each solvent, especially desorption efficiencies more than 95% were achieved when adsorbed by Chromosorb 106 and desorbed by $CS_2$ or o-xylene. 2. Desorption efficiencies descended over the storage period in any condition(p<0.05). For all three adsorbing media, while desorption efficiencies showed no significant difference(p>0.05) between room temperature and refrigeration a day of loading, samples kept in room temperature had higher desorption efficiencies than refrigerated ones in 7 and 14 days with significant difference(p<0.05).Also, desorption efficiencies dropped drastically in 7 days, from that point the decreasing tendency went mild. 3. When respective 1 TLV and 0.1 TLV of naphthalene were spiked on CCT and desorbed by CS2($46.45{\pm}0.59%$ vs. $30.15{\pm}0.81%$), o-xylene($73.96{\pm}0.53%$ vs. $67.51{\pm}1.34%$), and ether($1.14{\pm}0.03%$ vs. N.D.) desorption efficiencies increased as the amount of loading increased(p<0.05).On the other hand, naphthalene spiked on XAD-2 and Chromosorb 106 indicated no significant difference(p>0.05) in desorption efficiencies between 1 TLV and 0.1 TLV. In conclusion, in order for favorable desorption efficiencies of naphthalene it is important to select appropriate adsorbing media and desorbing solvent accordingly. The result revealed that adsorbing media of XAD-2 and Chromosorb 106 outperformed CCT and desorbing solvents of $CS_2$ and o-xylene achieved over 90% of desorption efficiencies when adsorbed on XAD-2 and Chromosorb 106. Also, considering the tendency that desorption efficiencies of naphthalene decrease with time, the samples should be analyzed as soon as possible.

• 수면정신생리
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• 제1권2호
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• pp.163-171
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• 1994

연구목적 : 수면 무호흡의 증상은 크게 불면증, 낮의 과다한 졸리움, 기억력과 집중력 등의 인지기능장애, 우울 등의 감정장애 등이 주 증상을 이루고 있다. 그런데 이러한 증상들이 수면 및 수면 무호홉의 여러 변수들과 어떤 상관관계를 가지며 어떤 과정을 통해서 구체적으로 발생되는 지에 대한 연구는 그렇게 많지 않다. 연구방법 : 본 연구는 수면 무호흡증 환자 60 명을 대상으로 수면다원검사를 실시함과 동시에 낮 졸리움 척도, 불면증 척도, 인지기능 척도 및 감정장애 척도를 통해 수면 무호홉의 증상을 평가하였다. 그리고 수면다원 검사상의 여러 수면변수, 무호흡의 횟수, $O_2$ desaturation, 코골기 정도 등과 무호흡 증상의 4 가지 척도와 상관관계를 조사하였다. 연구결과 : 유의한 상관관계를 보인 결과는 다음과 같다. 무호흡 환자 중 불면증호소가 적고 비교적 잠을 잘 자는 경우는 호흡장애가 많은 경우와 중심성 무호흡이 많은 경우였다. 그리고 제 3 단계 서파수면에서 코골기가 많거나 경등도의 산소저하가 많은 경우였다. 대신 낮에 졸리움증이 많은 경우는 제 1 단계에서 코골기가 많은 경우였다. 그러나 무호흡의 정도나 산소와는 직접 상관관계가 나타나지는 않았다. 우울 등의 감정장애는 수면 중 산소저하가 중등도이상으로 심한 경우 많이 나타났으며 제 4 단계 서파수면이 적은 경우 이러한 우울 감정이 더 심하게 나타났다. 집중과 기억 등의 인지기능은 REM 수면이 많고 호흡장애의 횟수가 적을수록 더욱 감소되는 현상을 보였다. 결론 : 무호흡의 증상은 서로 다른 원인과 기전을 통해 발생될 수 있으며 이러한 증상을 좀 더 객관적 평가할 수 있다면 환자의 수면 및 무호흡의 정도와 상태를 예측하는데 더욱 많은 도움을 줄 수 있을 것으로 기대된다.

• Asian-Australasian Journal of Animal Sciences
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• 제15권9호
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• pp.1348-1353
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• 2002

The purpose of this study was to evaluate the changes and readjustment capacity in the hematological characteristics of the horse during and after a prolonged training program. One pony and two hot-blooded horses were used in this study. Resting or basal blood parameters were assessed by collecting blood samples of the animals for 1 to 2 months prior to start of the training program. Each animal was subjected to arbitrary exercise for 30 min by an automatic hot trotter and was bled at 0, 15, 30, 45 (15 min of recovery), 60 (30 min of recovery), and 75 min (45 min of recovery) after onset of exercise. All animals were exercised 3 times a week over a fivemonth period. Hematological parameters including average white blood cell counts (WBC, ${\times}$$10^3$/$\mu$l), erythrocyte concentrations (RBC, ${\times}$$10^6$/$\mu$l), hematocrit (HCT, %), mean corpuscular volume (MCV, fl), number of platelets (PLT, ${\times}$$10^4$/$\mu$l), hemoglobin concentration (Hb, g/dl), mean corpuscular hemoglobin (MCH, pg), and mean corpuscular hemoglobin concentration (MCHC, g/dl) were analyzed using an automatic cell counter. All animals showed that RBC, WBC, and HCT were significantly (p<0.05) increasing from 7.09, 8.55, and 43.5 to 8.11, 9.67, and 49.5, respectively, during the 30 min of exercise and were back to or lower than the initial basis (resting and 0 min) 30 min after exercise. However, no significant differences were detected in MCV (50.3-51.3 fl), MCH (17.2-17.4 pg), and MCHC (33.7-34.4 g/dl) values (p>0.05) regardless of the training periods. Similar trends were observed after 1, 3, 4, and 5 months of training when compared to the resting state. When these parameters were analyzed by the effect of training periods (month), mean WBC concentrations significantly reduced in the fourth and fifth month after onset of training compared to that in resting condition or the first month of training program (p<0.05). The RBC values elevated at the second month (9.40) and reaching a significantly low level (p<0.001) at the fifth month (8.62) after training compared to the first month of training (7.89). In conclusion, a mild training program enhances blood parameters gradually in both the horse and the pony. Therefore, an optimized training program is beneficial in promoting the endurance performance of the horse.

• 유기물자원화
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• 제8권4호
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• pp.129-137
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• 2000

본 연구에서는 도시고함수율 유기성폐기물(MWWT)의 처리를 위하여, 음식물 쓰레기의 처리에 사용되었던 컨테이너 호기성 퇴비화 시스템과, 계분 및 축분처리에 사용되었던 직립 상향 기계식 교반기를 조합하여 개발하였다. 호기성 처리 공정은 운전이 쉽다는 점과 운전비용이 저렴하다는 점, 자연에서 이용하기 가장 편리한 안정된 부산물을 만들 수 있다는 장점에도 불구하고, 염분의 농축, 과도한 부형제의 사용에 의한 경제적 부담의 증가 및 설비의 대형화 등의 장애물을 가지고 있다. 개발된 공정은 이러한 문제점을 보완하고자 하수슬러지는 초기의 수분조절 및 고속발효를 위해 직립 밀폐형 반응조에서 5일간, 음식물쓰레기는 탈염과 수분조절을 위해 밀폐형 무교반 필터에서, 침출수는 폐수처리 장치에서 처리하였다. 실험결과 국내 퇴비에 품질규격을 만족하면서 부자재의 사용량을 3% 이내로 조절할 수 있어 기존공정의 문제점을 해결할 수 있는 가능성을 확인하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제31권11호
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• pp.1807-1817
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• 2018

Objective: This study aimed at investigating white striping (WS) and wooden breast (WB) cases in breast meat collected from commercial broilers. Methods: A total of 183 breast samples were collected from male Ross 308 broilers slaughtered at the age of 6 weeks (n = 100) and 7 weeks (n = 83). The breasts were subjected to meat defect inspection, meat quality determination and histology evaluation. Results: Of 183, 4 breasts from 6-week-old broilers were classified as non-defective while the others exhibited the WS lesion. Among the 6-week-old birds, the defective samples from the medium size birds (carcass weight ${\leq}2.5kg$) showed mild to moderate WS degree with no altered meat quality. Some of the breasts from the 6-week-old birds with carcass weight above 2.5 kg exhibited WB in accompanied with the WS condition. Besides of a reduction of protein content, increases in collagen matter and pH values in the defective samples (p<0.05), no other impaired quality indices were detected within this group. All 7-week-old broilers yielded carcasses weighing above 2.5 kg and showed abnormal characteristics with progressive severity. The breasts affected with severe WS and WB showed the greatest cook loss, hardness, springiness and chewiness (p<0.05). Development of WB induced significantly increased drip loss in the samples (p<0.05). Histology indicated necrotic events in the defective myofibers. Based on logistic regression, increasing percent breast weight by one unit enhanced the chance of WS and WB development with advanced severity by 50.9% and 61.0%, respectively. Delayed slaughter age from 6 to 7 weeks increased the likelihood of obtaining increased WS severity by 56.3%. Conclusion: Cases of WS and WB defects in Southeast Asia have been revealed. Despite few cases of the severe WS and WB, such abnormal conditions significantly impaired technological properties and nutritional quality of broiler breasts.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제20권4호
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• pp.341-354
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• 1998

GMI (Fibrel${(R)}$) is one of the dermal filling substances which have been successfully used for the treatment of depressed cutaneous scar and wrinkles. It's major components are; Gelatin powder, which provides a framework for the clot to form and remains stable under the scar, and ${\varepsilon}$-aminocaproic acid, which inhibits the production of fibrinolysin, and Plasma, which provides the necessary ingredients for collagen synthesis. GMI has advantages of low immunogenicity and increased longevity. It has been known to induce fibroblast activity and promote new collagen synthesis. We used 34 Sprague-Dawley rats which were bred under the same condition and duration. 18 of experimental animals were undergone cardiac puncture, and their blood were collected, centrifugated, and stored in freezer. Out of 16 animals, control group were injected with 2ml plasma into the subcutaneous tissue of Lt. scapular, while experimental group were implanted of 2 ml GMI into the Rt. same area. Experimental animals were sacrificed at the 3rd day, 5th day, 1st week and 2nd week respectively after implantation of GMI. To observe the histopathologic change of GMI and surrounding tissue reaction of GMI, we had examined with H&E staining, immunohistochemical staining with vimentin, ${\alpha}$-SMA, S-100 under LM and SEM. The obtained results were as follows ; 1. In LM study, the inflammatory cell infiltrations and granulation tissue formation were observed, and muscle tissues were well attached with adipose tissues in the control group. In the experimental group, inflammatory cell infiltrations had been observed by the 2nd week and irregular adipiose tissues and well differentiated mesenchymal tissues were examined. 2. In immunohistochemical study, the experimental group of ${\alpha}$-SMA study, there were a prominent positive response on endothelial development of granulation tissues and mesenchymal tissues compare with the control group. In vimentin study, positive response on mescenchymal fibroblast continued to 2nd week, but negative in the control group. In S-100 study, both groups were positively responded on irregular adipose tissues. 3. In SEM study, collagen fibers were embedded by the plasma by the 5th day in the control group, and in the 3rd day experiment GMI were resorved but communited with collagen fiber till the 1st week. Collagen fibers were infilt-rated into GMI at the 2nd week and the infilltrated GMI were conglomerated with the mature adipose cells and the collagen fibers. From the above results, GMI implantation in the subcutaneous tissue of Sprague-Dawley rat, the mild infiltration of inflammatory cells were showed till 2nd week and the granulation tissues were observed. GMI were nearly resorbed till 2nd week, but well attached with adipose tissue and collagen fibers. The endothelium and fibroblasts were actively proliferated. Adipose tissues and mesenchymal tissue cells were observed. As already expressed, GMI showed resorptive change in course of time without any early immune reaction, and seemed to induce fibroblast activity and promote new collagen synthesis.

• 한국수자원학회논문집
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• 제41권8호
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• pp.773-784
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• 2008

본 연구는 노면배수시설에 이용될 수로 양단에 유출구를 가지며 유량이 연속적으로 증가하는 선형 배수로의 부등류 흐름의 해석 방법을 정립하기 위하여 수행되었다. 지배 방정식으로서 유한 차분 형태의 대수방정식을 사용하여 지배단면에서의 수심 값을 경계조건으로 Newton-Raphson 방법에 의하여 수면곡선을 계산하였다. 하류단에 유출구를 갖는 수로와 수로 양단에 유출구를 갖는 수로를 고려하고, 다양한 종단경사에 대하여 흐름 해석을 수행하였다. 단, 양단에 유출구를 갖는 수로의 경우 양단을 지배단면으로 만드는 임계 종단경사를 조사하여 이보다 작은 종단경사에 대한 흐름 해석을 수행하였으며, 임계경사는 지배단면의 위치와 종단경사의 관계로부터 결정하였다. 하류단에 하나의 유출구를 갖는 수로의 경우 수로 상에 존재하는 지배단면의 위치를 조사하여 그 지점을 기준으로 상류 및 하류 방향으로 수심을 계산한다. 반면 양단에 유출구를 갖는 수로의 경우 지배단면이 수로 양단이라면 분수계를 가정하여 분수계를 기점으로 구분되어지는 상류측 및 하류측 수로에 대한 흐름 해석을 수행하고, 상류단에서 분수계 방향으로 그리고 하류단에서 분수계 방향으로 계산된 분수계 지점의 두 수심이 동일할 때까지 흐름 계산을 반복한다. 흐름 계산 결과 양단에 유출구를 갖는 수로가 임계경사보다 큰 경사로 설치된 경우에는 하류단에 유출구를 갖는 수로의 흐름 거동과 유사지는 것으로 판단되었다. 노면배수시설 설계의 중요한 요소인 최대수심은 종단경사가 작을 때 등류 해석으로 계산된 값이 부등류 해석보다 크게 산정되었으며, 이는 종단경사가 작을 때 등류 해석을 기반으로 한설계가 과대설계가 되기 쉽다는 것을 의미한다.

• Korean Chemical Engineering Research
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• 제54권4호
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• pp.443-447
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• 2016

미세조류 세포벽은 셀룰로오스가 주요 구성성분으로 리그닌을 포함하지 않아 낮은 온도의 전처리 조건에서도 효과적으로 셀룰로오스와 헤미셀룰로오스 분해가 가능하다. 차세대 바이오매스로 주목 받는 미세조류(Tetraselmis KCTC 12236BP)로부터 $120^{\circ}C$ 이하의 낮은 온도 조건에서 열수전처리를 이용한 발효당 생산 증대를 위해 공정조건을 최적화하였다. 주요 공정조건인 추출온도, 황산농도와 추출시간에 따른 당화율 변화를 확인하였을 때, 온도와 황산농도가 글루코오스 생산에 큰 영향을 컸으며 당화율이 비례하여 증가하는 경향을 보였다. 경제성을 고려한 열수전처리 최적조건은 $120^{\circ}C$, 2 mol 황산, 40분으로 95.9%의 당화율을 얻을 수 있었다. 탈지미세조류의 황산 열수전처리와 효소당화를 비교했을 때, 황산 열수전처리의 당화율이 2.1배 이상 높고 전처리 시간이 짧아 황산 열수전처리가 효소당화에 비해 효과적인 공정임을 확인하였다.

• 한국융합학회논문지
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• 제6권5호
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• pp.295-302
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• 2015

본 연구는 노인의 여가력, 가족상태의 융 복합적 접근을 통한 노인의 우울성향을 심층적으로 비교 분석하였다. 본 연구는 65세 이상(평균 73.5세)의 여성노인 20명이 참여하였으며, 대상자의 여가력 분석은 심층면접법으로 총 10문항으로 구성된 구조화된 질문을 통해 여가력을 파악하였으며 가족상태 설문은 가족의 형태, 동거여부 등 총 7문항으로 구성된 설문지를 사용하였다. 우울증 측정은 Geriatric Depression Scrennng; GDS)를 이용하였다. GDS결과에 따라 우울집단과 정상집단을 구분하였으며, 여가력, 가족상태를 통해서 파악한 노인의 우울성향을 비교한 결과는 다음과 같다. 여가력에서 여가의 만족도가 우울만족도에 긍정적 영향을 미쳤으며(F(2,17)=3.989, p<.05), 반면 여가력이 낮거나, 여가동반자가 없는 경우 높은 퇴행적 우울증상을 보였다. 가족상태 중에 본인의 질환 종류에 따라 우울성향에 유의한 영향을 미치는 것으로 분석되었으며(F(3,16)=4.534, p<.05), 그 외 동거유무, 동거인의 건강상태가 우울성향의 평균값의 차이는 높게 나타났다. 결과 노인의 우울 증상은 표현력이 부족하여 우울성향을 쉽게 파악할 수 없으나 오랜 과거력과 주변의 영향을 많이 받는 것으로 나타나 가족의 범주에서 확대하여 지역사회 네트워크와의 관계와 우울에 관한 연구도 필요할 것으로 보인다. 또한, 여가에 있어서도 신체적, 정서적, 사회적 활동의 형태, 활동의 방법, 활동의 정도를 중심으로 한 일회적인 연구가 아니라 종단적 연구를 통해 향후 노인의 여가참여의 질을 높일 수 있는 융복합적 후속연구가 필요할 것으로 사료된다.

• Journal of Periodontal and Implant Science
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• 제30권2호
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• pp.359-374
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• 2000

Cyclosporine A(CsA) is a widely used immunosuppressant for transplant patients and is also used for the treatment of a wide variety of systemic diseases with immunologic disorders. However, its use is frequently limited because of complications such as nephrotoxicity or gingival hyperplasia. Although several hypotheses have been postulated for CsA-induced gingival hyperplasia, i.e. various cytokine effects of inflammatory cells, existence of plaque or CsA itself, but its pathogenesis is still unclear. For experimental chronic CsA toxicity, salt depletion has been shown to increased susceptibility of rodents to the effects of CsA, and this maneuver facilitates production of arteriolopathy and interstitial fibrosis in kidney that mimic the changes found in human. The purpose of this study was to evaluate pathogenesis of CsA-induced gingival hyperplasia by comparing changes between CsA administration groups of normal standard diet and those of low salt diet group. Specific pathogen-free, 20 to 25 days old(120 to 150 g), male Fisher-344 rats(KIST, Korea), 120 to 150g of body weight, were assigned to four groups of six animals each after one week of adaptation period for powder food. Group 1 received olive oil($300{\mu}l/g\;of\;diet$) with normal standard diet(0.4% of sodium)(NSD). Group 2 received CsA(Cypol-N, Jonggundang, Korea; $300{\mu}g/g\;of\;diet$) with normal standard diet(NSD+CsA). Group 3 received same amount of olive oil with low salt diet(0.05 % of sodium, Teklad Premier, U.S.A.)(LSD). Group 4 received same dose of CsA with low salt diet(LSD+CsA). Rats were pair fed and were sacrificed after six weeks. Renal histologic lesions associated with CsA, consisted of cortical interstitial fibrosis, tubular atrophy and hyalinization of arterioles and the impairment of renal function including increase of serum creatinine and decrease of glomerular filtration rate was more severe in low salt diet group. These were proved as the results of activated of renin-angiotensin system in the kidney by low salt condition. Meanwhile the degree of gingival hyperplasia at incisor and molar tooth was less severe in low salt diet group compared with normal sodium diet group. Hyperplastic gingiva showed mild epithelial hyperplasia and expanded underlyng stroma which consisted of matrix increasement, capillary proliferation and dilatation. While the number and the activation of fibroblasts were increased, inflammatory cells were rare in the stroma. The immunohistochemistry for TGF-${\beta}_1$ in the kidney and gingiva revealed stronger positive in LSD+CsA in kidney but in gingiva of NSD+CsA. These results suggested followings; Gingival hyperplasia can be developed without inflammatory cells infiltration and seemed not induced by CsA by itself. The major role for gingival hyperplasia by CsA would be the secondary effect of TGF-${\beta}$, which maybe upregulated by CsA administration. Low salt diet can attenuate this hyperplasia perhaps by decreasing the activation of $TGF-{\beta}$.