Accuracy of cardiac output measurements during off-pump coronary artery bypass grafting: according to the vessel anastomosis sites

Sung Yong Park,Dae Hee Kim,Han Bum Joe,Ji Young Yoo,Jin Soo Kim,Min Kang,Yong Woo Hong 대한마취통증의학회 2012 Korean Journal of Anesthesiology Vol.62 No.5

Background: During beating heart surgery, the accuracy of cardiac output (CO) measurement techniques may be influenced by several factors. This study was conducted to analyze the clinical agreement among stat CO mode (SCO), continuous CO mode (CCO), arterial pressure waveform-based CO estimation (APCO), and transesophageal Doppler ultrasound technique (UCCO) according to the vessel anastomosis sites. Methods: This study was prospectively performed in 25 patients who would be undergoing elective OPCAB. Hemodynamic variables were recorded at the following time points: during left anterior descending (LAD) anastomosis at 1 min and 5 min; during obtuse marginal (OM) anastomosis at 1 min and 5 min: and during right coronary artery (RCA) anastomosis at 1 min and 5 min. The variables measured including the SCO, CCO, APCO, and UCCO. Results: CO measurement techniques showed different correlations according to vessel anastomosis site. However, the percent error observed was higher than the value of 30% postulated by the criteria of Critchley and Critchley during all study periods for all CO measurement techniques. Conclusions: In the beating heart procedure, SCO, CCO and APCO showed different correlations according to the vessel anastomosis sites and did not agree with UCCO. CO values from the various measurement techniques should be interpreted with caution during OPCAB. Background: During beating heart surgery, the accuracy of cardiac output (CO) measurement techniques may be influenced by several factors. This study was conducted to analyze the clinical agreement among stat CO mode (SCO), continuous CO mode (CCO), arterial pressure waveform-based CO estimation (APCO), and transesophageal Doppler ultrasound technique (UCCO) according to the vessel anastomosis sites. Methods: This study was prospectively performed in 25 patients who would be undergoing elective OPCAB. Hemodynamic variables were recorded at the following time points: during left anterior descending (LAD) anastomosis at 1 min and 5 min; during obtuse marginal (OM) anastomosis at 1 min and 5 min: and during right coronary artery (RCA) anastomosis at 1 min and 5 min. The variables measured including the SCO, CCO, APCO, and UCCO. Results: CO measurement techniques showed different correlations according to vessel anastomosis site. However, the percent error observed was higher than the value of 30% postulated by the criteria of Critchley and Critchley during all study periods for all CO measurement techniques. Conclusions: In the beating heart procedure, SCO, CCO and APCO showed different correlations according to the vessel anastomosis sites and did not agree with UCCO. CO values from the various measurement techniques should be interpreted with caution during OPCAB.

쿠싱증후군 환자에서 당 대사 이상 정도에 따른 인슐린 감수성과 인슐린 저항성의 변화

정인경,김성훈,정재훈,민용기,이명식,이문규,유형준,안규정,노정현,김동준,김광원 대한내분비학회 2003 Endocrinology and metabolism Vol.18 No.4

연구배경 당질 코르티코이드는 당 대사에 매우 중요한 호르몬으로 내인성 당질 코르티코이드 과다상태인 쿠싱증후군에서는 말초조직에서 인슐린 저항이 증가하고 이를 보상하고자 인슐린 분비의 증가로 고인슐린혈증이 동반된다고 보고되고 있다. 하지만 생체 내에서와 달리 시험관내에서는 췌도세포에 당질 코르티코이드를 장시간 처리하면, 인슐린 분비 및 생합성이직접적으로 억제됨이 확인된 바 있어 쿠싱증후군 환자에서 당뇨병의 원인으로는 아마도 말초조직에서 증가된 인슐린 저항성 뿐 아니라 이를 충분히 보상하지 못하는 췌장에서의 인슐린 분비 저하가 같이 동반되어있지 않을까 하는 가설을 세우게 되었고, 아직까지 당질코르티코이드가 당대사 이상을 일으키는 기전에 대해 쿠싱증후군을 당대사 정도에 따라 인슐린 감수성과 분비능을 분석한 연구는 없었기에 이를 알아보고자 하였다. 방법: 삼성서울병원에서 쿠싱증후군으로 진단 받은 환자 15명을 대상으로 하였다. 이에 대한 대조군으로는 쿠싱증후군 환자와 같은 성별 그리고 체질량지수를 갖은 15명의 건강한 성인을 대상으로 비교 하였다 쿠싱증후군 환자를 대상으로 경구당부하 검사를 통해 당대사 정도를 정상군, 내당능장애군, 그리고 당뇨병군으로 나눈 후 정맥 당부하 검사를 시행하여 각군의 인슐린 저항성과 인슐린 분비능의 지표를 비교하고, 수술 후 쿠싱증후군이 완치된 상태에서 수술 전후의 당대사 지표의 변화를 조사하였다. 결과: 1) 쿠싱증후군 환자 중 정상인은 20%, 내당능 장애는 27%, 그리고 당뇨병은 53%였다. 체질량지수, 나이, 그리고 발병 기간은 세 군간에 의미 있는 차이가 없었으나, 24시간 소변검사의 코르티솔 농도는 당뇨병군에서 의미있게 높았다. 2) 정맥당부하 검사 결과, 인슐린 감수성 지표인 Sl는쿠싱증추린」서 1.58±0.10[×10^(-4)(min^(-1)(μU/mL)^(-1)]로 정상 대조군의 3.37±0.49[×10^(-4)(min^(-1)(μU/mL)^(-1)]에 비해 의미있게 낮았으나(P=0.024), 쿠싱증후군 환자 중 NGT, IGT, DM 군간에 서로 통계적인 차이는 없었다. 3) SG는 정상 대조군과 쿠싱증후군 환자간에는 의미있는 차이가 없었고, 쿠싱 증후군에 있어서 당대사가 악화될수록 감소하는 경향을 보였으나 의미있는 차이는 없었다. 4) 인슐린 분비능의 지표인 AIRg는 정상인에 비해 전체 쿠싱증후군 환자의 경우 증가하는 경향을 보였으나 의미있는 차이는 없었다. 하지만 쿠싱증후군 환자중에서 당대사 상태에 따라 NGT군은 1299 (1297∼1310)(mu/g/min ×10^(-2))로 정상 대조군(368.9±98.6[mu/g/min ×10^(-2)]) 보다도 의미있게 높았고, DM군{202.2 (91.1~371.4) [mu/g/min ×10^(-2)}은 NGT군에 비해 의미있게 낮았다(P=0.0031). 5) 15명중 현재 완치 상태에 있는 6명에 대해 수술전과 후로 비교하였다. 수술 전 당대사 상태가 1명은정상, 1명은 내당능 장애, 그리고 4명은 당뇨병이었으나 수술 후 시행한 경구 당부하 검사상 모두 정상 당대사 상태를 보였다. 6) 수술 후 완치된 환자 6명에 있어 인슐린 감수성지표인 Sl는 수술전에 중앙값이 1.22[×10^(-4)(min^(-1)(μU/mL)^(-1)]로 대조군에 비해 의미있게 감고』어 있었으나(p.0.05), 수술후 10.95 [×10^(-4)(min^(-1)(μU/mL)^(-1)]로 정상 수준으로 회복되었고(P=0.0022), 인슐린 분비능을 나타내는 AIRg [mu/g/min ×10^(-2)] 값도 정상수준으로 회복되었다. 특히 인슐린 분비능의 회복양상은 혈당농도에 따라 판이하게 나타나서, 정상과 내당능장애 상태에 있던 2명은 수술전에 1201 [mu/g/min ×10^(-2)]로 증가되어 있던 AIRg 값이 수술 후 정상 수준으로 감소하였고, 수술 전에 당뇨병 상태에 있던 4명의 경우 245.9 [mu/g/min ×10^(-2)]로 인슐린 분비능이 감고il어 있었는데 이들은 수술 후 모두 정상 수준으로 증가되었다 (P=0.0286). 결론: 쿠싱증후군 환자에서 당대사 이상은 80%로 높은 유병률을 보였다. 모든 쿠싱증후군환자에서 인슐린 감수성은 정상인에 비해 저하되어 있어 말초조직의 인슐린 저항이 선행됨을 시사하며, 인슐린 분비능은 당대사의 정도에 따라 다르게 나타났는데, 정상 당대사군에서는 인슐린의 저항성을 극복할 만큼 정상 대조군보다 더 많은 양의 인슐린 분비를 하다가 고코르티솔혈증이 심할수록 인슐린 분비능의 감소로 당뇨병으로 진행됨을 확인할 수 있었고, 이런 인슐린 저항성과 인슐린 분비장애는 수술 후 다시 회복되는 가역적인변화를 보였다. Background: Glucocorticoid plays an important role in the control of carbohydrate metabolism. Patients with Cushing's syndrome have been reported to have an increased incidence of carbohydrate intolerance due to peripheral insulin resistance and hyperinsulinemia, although the exact incidence and nature of this disorder have remained unclear. Few results have been published about insulin resistance and insulin secretion according to the level of glucose concentration, or about the reversibility of such defects in patients with Cushing's syndrome. Methods: To assess the effect of glucocorticoid on the insulin sensitivity and insulin secretion in Cushing's syndrome, 15 patients with Cushing's syndrome were classified into 3 groups (normal glucose tolerance: NGT, impaired glucose tolerance: IGT, diabetes: DM) according to the degree of glucose tolerance based on the oral glucose tolerance test (OGTT). Insulin modified, frequently sampled, intravenous glucose tolerance test (FSIGT) was performed before and after curative surgery on these patients and on 15 healthy control subjects. Data were evaluated by non-parametric statistical analysis. Results: 1) Among the 15 patients with Cushing's syndrome, 3 (20%) were NGT, 4 (27%) IGT, and 8 (53%) DM, based on OGTT. Twenty-four hour urinary free cortisol (UFC) was significantly higher in the DM group. 2) Insulin sensitivity index (SI) of Cushing's syndrome was significantly lower than that of the control group p=0.0024), but was not significantly different among the three Cushing's syndrome groups of NGT, IGT and DM. 3) Glucose mediated glucose disposal (SG) (Ed- confirm this abbreviation; it does not seem to match the definition) of Cushing's syndrome was not significantly different from that of the control group. 4) Insulin secretion (AIRg) of Cushing's syndrome tended to be high, but it was not significantly different from that of control. However, according to the level of glucose concentration there was significant difference in AlRg among the three Cushing's syndrome groups p=0.0031); AIRg of DM was significantly lower than that of NGT. 5) After surgical treatment, parameters of insulin sensitivity and insulin secretion were normalized in 6 cured patients; 1 with NGT, 1 with IGT, and 4 with DM, preoperatively. Median SI of all 6 patients was significantly improved up to the normal range postoperatively p=0.0022). Median AIRg of these 6 patients was balanced around that of normal control postoperatively p=0.0286). Conclusion: Eighty percent of patients with Cushing's syndrome had abnormality of carbohydrate metabolism. Insulin sensitivity was significantly decreased in Cushing's syndrome. Insulin secretion was significantly higher only in the NGT and IGT groups of Cushing's syndrome. As the hypercortisolemia is exacerbated, insulin secretion is significantly decreased and causes DM, suggesting that glucocorticoid has a direct or indirect toxic effect on the pancreatic beta cell (J Kor SOC Endocrinol 18:392-403, 2003).

가열 조건을 달리한 단호박 페이스트와 검 종류별 단호박 라떼의 품질특성

박보람,김나정,유선미,한귀정,김하윤,한혜민,신동선,신말식,Park, Bo-ram,Kim, Na-Jung,Yoo, Seon-Mi,Han, Gwi Jung,Kim, Ha Yoon,Han, Hye-min,Shin, Dong-Sun,Shin, Malshick 한국식품조리과학회 2015 한국식품조리과학회지 Vol.31 No.3

가열 조건에 따른 단호박 페이스트를 제조하기 위해, 단호박을 15분 간 초벌 증숙한 뒤, 고압가열 처리 0분(A), 10분(B), 20분(C), 40분(D) 실시하여 실험군의 품질특성 을 조사하였다. 그 결과 일반성분의 경우, 대체적으로 고 압가열 처리 유무에 따른 유의적 차이가 관찰되었으며, 고압가열 처리한 B, C, D 실험군의 수분함량, 조단백질, 조섬유가 고압가열 무처리군 A에 비해 감소하였고, 가용성 무질소물은 증가하는 것으로 나타났다. 가열 조건별 단호박 페이스트의 수용성식이섬유는 고압가열 20분 처리군인 C의 측정치가 2.02로 가장 높았으며 무처리군인 A의 1.60 보다 증가하였고, 고압가열 처리 40분의 경우 오히려 감소하는 것으로 나타났다. 색도의 L 값은 고압가열 무처리군인 A가 52.20에서 고압가열 처리 10분, 20분, 40분으로 시간이 증가함에 따라 각각 50.33, 49.46, 48.06으로 감소하였고, a 값과 b 값 또한 유의적인 차이를 보이며 감소하였다. 현미경을 통한 단호박 페이스트의 현탁액 입자를 관찰한 결과 카로티노이드를 포함하는 유세포가 관찰되었으며 고압가열 처리와 그 시간이 증가함에 따라 단호박 유세포의 변형이 뚜렷하게 관찰되었으나, 부유안정성 실험 결과 실험군 A, B, C, D 간 차이가 없었다. 이때, 가열조건의 선택은 수용성 식이섬유의 증가, 환원당 증가, 단맛의 관능특성이 유의적으로 높고, 전반적 기호도가 가장 우수한 것으로 나타난 고압가열 처리 20분인 C 실험군으로 결정하였다. 선택된 조건의 단호박 페이스트에 식품가공 시 널리 사용되는 검류인 xanthan gum, locust bean gum, guar gum을 단호박 페이스트에 종류별로 첨가하여 부유안정성을 확인하였는데, 이 결과 guar gum, locust bean gum, xanthan gum 순으로 부유안정성 효과를 나타냈으며 locust bean gum과 xanathan gum은 비슷한 정도의 효과를 보였다. 또한 관능검사를 통한 기호도 확인 결과 텍스쳐와, 전반적인 기호도가 가장 우수했으므로 locust bean gum(0.2%) 첨가 단호박 라떼의 품질이 가장 적절할 것으로 판단된다. For the production of pumpkin paste with respect to heating conditions, we steamed the pumpkin for roughly 15 min, heated it with high pressure treatment for 0 min (A), 10 min (B), 20 min (C), 40 min (D), and subsequently investigated the quality characteristics. Generally a significant difference was observed between the pumpkin paste treated with and without high-pressure heat. The values of water content, crude protein and crude fiber of the high-pressure heat-treated groups B, C, D were decreased compared with untreated group A. The soluble fiber in experimental group B sweet-pumpkin paste treated with high-pressure heat for 20 min was higher than the control, and the highest value at 2.02. Experimental group D sweet-pumpkin paste treated with high-pressure heat for 40 min was found to have a decreased soluble fiber content relative to the control. The L value for the color of the group A untreated control sweet-pumpkin paste (no high-pressure heating) decreased as the time increased from 10 min to 40 min, with L values of 50.33, 49.46, and 48.06, respectively. The b value for the color of the sweet-pumpkin paste also decreased, showing a significant difference. Taking into account all the results, we chose experimental group B in order to prepare sweet-pumpkin latte. We used 0.2% gum (xanthan gum, locust bean gum, guar gum) as a stabilizer. Sweet-pumpkin latte with xanthan and locust bean gum has a suspension stability effect that lasts 90 min. The L and b values of sweet-pumpkin latte with gums increase and a value decrease compared with the control. In terms of the overall acceptance of the sweet-pumpkin latte, the experimental group with xanthan gum scored the best.

Preparation and Evaluation of Gelatin - Acacia Microcapsules of Sulfamethoxazole

Lee, Min Hwa,Yoo, Bong Gyu 한국약제학회 1982 Journal of Pharmaceutical Investigation Vol.12 No.4

Sulfamethoxazole particles were microencapsulated using the gelatin-acacia complex coacervation method. Micromeritic properties and dissolution characteristics of the microcapsules were studied. The particle size distribution followed log-normal form. As the hardening time increased, the particle size and wall thickness increased (45.3-52.0 ㎛, 2.02-5.12 ㎛, respectively). This is considered to be due to the cross-linked wall structure of formalized microcapsules which prevents shrinking of gelatin during the dehydration and drying processes. An increase of hardening time clearly delayed the release rate. The in vitro 50% dissolution time (t_(50)) for unencapsulated sulfamethoxazole powder was less than 3 min. ; for microcapsules hardened for 30 min, the t_(50) was 20.1 min. ; for those hardened for 60 min. the t_(50) was 25.0 min. ; for those hardened for 120 min., the t_(50) was 35.8 min. The surface of the unhardened microcapsules was smooth and had no cracking or pore penetration. However, the surface of the hardened microcapsules was folded and invaginated.

Development of electrochemical biosensor for detection of pathogenic microorganism in Asian dust events

Yoo, Min-Sang,Shin, Minguk,Kim, Younghun,Jang, Min,Choi, Yoon-E,Park, Si Jae,Choi, Jonghoon,Lee, Jinyoung,Park, Chulhwan Elsevier 2017 CHEMOSPHERE - Vol.175 No.-

<P><B>Abstract</B></P> <P>We developed a single-walled carbon nanotubes (SWCNTs)-based electrochemical biosensor for the detection of <I>Bacillus subtilis,</I> one of the microorganisms observed in Asian dust events, which causes respiratory diseases such as asthma and pneumonia. SWCNTs plays the role of a transducer in biological antigen/antibody reaction for the electrical signal while 1-pyrenebutanoic acid succinimidyl ester (1-PBSE) and ant-<I>B. subtilis</I> were performed as a chemical linker and an acceptor, respectively, for the adhesion of target microorganism in the developed biosensor. The detection range (10<SUP>2</SUP>–10<SUP>10</SUP> CFU/mL) and the detection limit (10<SUP>2</SUP> CFU/mL) of the developed biosensor were identified while the response time was 10 min. The amount of target <I>B. subtilis</I> was the highest in the specificity test of the developed biosensor, compared with the other tested microorganisms (<I>Staphylococcus aureus</I>, <I>Flavobacterium psychrolimnae</I>, and <I>Aquabacterium commune</I>). In addition, target <I>B. subtilis</I> detected by the developed biosensor was observed by scanning electron microscope (SEM) analysis.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A SWCNTs-based biosensor was developed for the detection of <I>Bacillus subtilis.</I> </LI> <LI> The biosensor was composed of SWCNTs, 1-PBSE, and anti-<I>B. subtilis</I> antibody. </LI> <LI> The performance of the biosensor was assessed using a sensor sensitivity and specificity tests. </LI> <LI> The detection limit and detection range were 10<SUP>2</SUP> and 10<SUP>2</SUP>–10<SUP>10</SUP> CFU/mL, respectively. </LI> <LI> The detection time of the biosensor was identified as 10 min. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

중학생들의 인터넷 중독 위험수준에 따른 신체활동량과 비만도의 관련성

정민기(Jeong, Min-Ki),김권민(Kim, Gwon-Min),권유찬(Kwon, Yoo-Chan) 한국체육과학회 2015 한국체육과학회지 Vol.24 No.4

The purpose of this study was to examine the association perceived physical activity pattern and body mass index according to habitual internet usage among middle school student. Data were analyzed for 969 students who responded to self-reported base cross-sectional survey relating to socio-demographic variables, internet usage status, and a short version of the international physical activity questionnaire. Prevalence rate of physical activity status showed that 53.5% at 150 min/week under, 46.5% at 150min/week over. Prevalence rate of internet usage showed that 95.6% at normal group, 2.6% at potential group, 1,9% at addiction group. Prevalence rate of body mass index status of over weight according to internet usage status shoed that 83.1% at normal, 5.1% at potential, 11.9% at addiction. Prevalence rate of physical activity levels of 150 min/week under according to internet usage status showed that 93.8% at normal, 3.5% at potential, 2.7% at addiction. In comparison with the physical activity levels was significantly more likely potential internet usage (OR, 2.62; 95% confidence interval [95%CI], 1.09-6.47; p〈.05) and addiction usage (OR, 3.82; 95% confidence interval [95%CI], 1.24-11.75; p〈.05). The results revealed that physical activity levels and body mass index correlates of internet usage status. This finding suggest the necessity of developing specific strategies for physical activity intervention by internet addiction among middle school students.

D-Amphetamine이 니코틴성 흥분작용에 의한 카테콜아민 분비작용에 미치는 영향

임건한,서유석,민선영,임지연,김용직,나광문,임동윤 朝鮮大學校 附設 醫學硏究所 2005 The Medical Journal of Chosun University Vol.30 No.1

본 연구의 목적은 d-arphetamine이 흰쥐의 적출부신 관류모델에서 니코틴 수용체 흥분에 의한 카테콜아민(CA) 유리작용에 미치는 영향을 검색하여 그 작용기전을 규명하고자 하였다. D-amphetamine은 흰쥐 부신정맥내로 60분간 관류시 d-amphetamine자체는 약한 CA 분비작용을 나타내었으나, d-amphetamine (30 μM)을 비롯한 강력한 neuronal nicotine 수용체 작용제인 cytisine (50 μM) 및 epibatidine (30 μM)에 의한 CA 유리작용을 처음 4-10분 동안만 유의하게 증강시켰다. 또한, d-amphetamine (30 μM)은 60분간 부신정맥 내로 관류한 상태에서 dihydropyridine L-형 칼슘통로 개방약물인 Bay-K-8644 (10 μM)과 세포질내 칼슘저장고에서 Ca^(2+) ATPase 억제제인 cyclopiazonic acid (10 μM)의 CA 유리작용을 처음 4분간만 유의하게 증강시켰다. 그러나, 고농도의 d-amphetamine (500 μM)은 상기한 모든 분비촉진제의 CA분비작용을 오히려 억제하였다. 이와 같은 연구결과로 보면, 흰쥐 관류 부신수질에서 d-amphetamine은 낮은 농도에서는 콜린성 니코틴 수용체 흥분에 의한 카테콜아민 분비반응을 증강시키지만, 고농도에서는 오히려 억제적으로 작용함을 시사한다. 따라서, d-amphetamine은 용량에 따라서 흰쥐 적출 관류부신수질의 니코틴 수용체의 작용제 및 길항제로 이중 작용(dual action)을 나타내는 것으로 생각된다. 이러한 d-amphetamine의 작용은 흰쥐 부신수질 크롬친화세포의 dihydropyridine계 L-형 칼슘통로의 활성화 및 세포 내 칼슘저장고로부터 칼슘유리작용과 관련성이 있는 것으로 사료된다. The purpose of the present study was to examine the effect of d-amphetamine on CA release evoked by nocotinic receptor stimulation from the isolated perfused model of the rat adrenal gland, and to establish its mechanism of action. D-amphetamine(30 μM), when perfused into an adrenal vein of the rat adrenal gland for 60 min, enhanced the CA secretory responses evoked by ACh (5.32 mM), nicotine (30 μM), cytisine (50 μM, a selective neuronal nicotinic Nn-receptor agonist) and epibatidine (30 nM, a selective neuronal nicotinic Nn receptor agonist) only for the first period (4~10 min), although it alone has weak effect on CA secretion. Moreover, d-amphetamine (30 μM) in to an adrenal vein for 60 min also augmented the CA release evoked by BAY-K-8644, an activator of the dihydropyridine L-type Ca^(2+) channels, and cyclopiazonic acid, an inhibitor of cytoplasmic Ca^(2+) ATPase only for the first peroid (4 min). However, in the presence rather inhibited the CA secretory responses evoked by the above all of secretagogues. Taken together, these experimental results suggest that d-amphetamine at a low concentration enhances the CA secretion from the rat adrenal medulla evoked by stimulation of cholinergic nicotininc receptors, but at a high concentration it rather inhibits them. It semms that d-amphetamine has dual action acting as both agonist and antagonist at nicotinic receptors of the isolated perfused rat adrenal medulla, which are might be dependent on the concentration. It is also thought that these actions of d-amphetamine are probably relevant to the activation of the dihydropyridine L-type Ca^(2+) channels located on the rat adrenomedullary chromaffin cell membrane and release of Ca^(2+) from the cytoplasmic store.

습식텍스쳐를 이용한 단결정 실리콘 광학적 · 전기적 특성 연구

한규민(Han Kyu-min),유진수(Yoo Jin-su),유권종(Yoo Kwon-jong),이희덕(Lee Hi-deok),최성진(Choi Sung-jin),권준영(Kwon Jun-young),이준신(Yi Jun-sin) 한국태양에너지학회 2010 한국태양에너지학회 학술대회논문집 Vol.2010 No.4

The presence of ultrasonic wave in caustic cleaning process enhances the remove pollutants, and more homogeneous, textured structure. The silicon wafers, cleaning in Deconex OF 145 solution (0.5~2wt %) with DIW under ultrasonic environment for 5 min. The presence of uniform thin layer of SiO2 on c-Si surface enhances etching rate in the caustic etching mixture solution of NaOH (1.5 wt %), DI water and IPA (6 wt %) at 90℃ for 20 min and results in a fine, more homogeneous and small textured structure.

대학생들의 인터넷 사용정도에 따른 신체활동량과 신체구성의 관련성

김권민(Kim, Gwon-Min),박상갑(Park, Sang-Kab),권유찬(Kwon, Yoo-Chan) 한국체육과학회 2015 한국체육과학회지 Vol.24 No.3

The purpose of this study was to examine the association perceived physical activity patten and body composition according to habitual internet usage among university students. Data were analyzed for 500 students who responded to an self-reported based cross-sectional survey relating to socio-demographic variables, internet usage status, and a long version of the international physical activity questionnaire. Prevalence rate of physical activity status showed that 40.2% at 150 min/week over, 59.8% at 150 min/week under. Prevalence rate of internet usage showed that 94.6% at normal group, 3.0% at potential, 2.4% at addiction. Prevalence rate of physical activity levels of 150 min/week under according to internet usage status showed that 92.0% at normal, 4.3% at potential, 3.7% at addiction. In comparison with the physical activity levels was significantly more likely potential internet usage (OR, 4.82; 95% confidence Interval [95%CI], 1.07, 21.86; p〈.05) and addiction usage (OR, 8.00; 95% confidence interval [95%CI], 1.02, 62.56; p〈.05) The results revealed that physical activity levels correlates of internet usage status. This findings suggests the necessity of developing specific strategies for physical activity intervention by internet addiction among university students.

스마트폰 사용정도가 수면의 질과 좌식행동에 미치는 영향

김권민(Kim, Gwon-Min),정민기(Jeong, Min-Ki),권유찬(Kwon, Yoo-Chan) 한국체육과학회 2016 한국체육과학회지 Vol.25 No.1

The purpose of this study was to examine the association perceived physical activity pattern and body mass index according to habitual internet usage among middle school student. Data were analyzed for 969 students who responded to self-reported base cross-sectional survey relating to socio-demographic variables, internet usage status, and a short version of the international physical activity questionnaire. Prevalence rate of physical activity status showed that 53.5% at 150 min/week under, 46.5% at 150min/week over. Prevalence rate of internet usage showed that 95.6% at normal group, 2.6% at potential group, 1.9% at addiction group. Prevalence rate of body mass index status of over weight according to internet usage status showed that 83.1% at normal, 5.1% at potential, 11.9% at addiction. Prevalence rate of physical activity levels of 150 min/week under according to internet usage status showed that 93.8% at normal, 3.5% at potential, 2.7% at addiction. In comparison with the physical activity levels was significantly more likely potential internet usage (OR, 2.62; 95% confidence interval [95%CI], 1.09-6.47; p<.05) and addiction usage (OR, 3.82; 95% confidence interval [95%CI], 1.24-11.75; p<.05). The results revealed that physical activity levels and body mass index correlates of internet usage status. This finding suggest the necessity of developing specific strategies for physical activity intervention by internet addiction among middle school students.