The Association Between Long Working Hours and Infertility

Ahn Joonho,Lee Sang Ha,Park Min Young,Oh Soo Hyun,Lee Wanhyung 한국산업안전보건공단 산업안전보건연구원 2021 Safety and health at work Vol.12 No.4

Background: This study aimed to investigate whether working long hours was related to infertility among female Korean workers, while taking age into consideration. Methods: We used data from the 2018 National Survey on Fertility and Family Health and Welfare in Korea that is a cross-sectional, nationally representative, and population-based survey. Infertility was defined as women who were not pregnant after regular unprotected intercourse for a year. Working long hours was classified as ≥52 hours, and subgroups as per age were classified on the basis of being younger or older than 40 years of age. Differences in infertility risk between the long working hour group and none were estimated in crude and fully adjusted logistic regression models with age-group stratification. Results: Of 5,909 Korean female workers, the crude and adjusted odds ratios (95% confidence intervals) of infertility for working long hours were 1.295 (0.948-1.737) and 1.303 (0.921-1.809), respectively. In the subgroup of patients below 40 years of age, the crude and adjusted odds ratios (95% confidence interval) were 1.957 (1.216-3.039) and 1.921 (1.144-3.120), whereas those aged 40 years or older had 0.994 (0.647-1.471) and 0.939 (0.560-1.501), respectively. The weighted prevalence of infertility increased as weekly working hours increased only for the younger than 40-year subgroup. Conclusions: Infertility is associated with working long hours, especially in young-aged workers. Thus, the working schedule must be structured to better suit young female workers.

인터넷 중독 청소년들의 정신병리 및 대처 방식

안영균(Young Kyun Ahn),신영철(Young Chul Shin),고복자(Bok Ja Koh),심진현(Jin Hyun Shim),김범조(Bum Jo Kim),이승민(Seung Min Lee),이길홍(Kil Hong Lee) 한국중독정신의학회 2005 중독정신의학 Vol.9 No.1

This study was conducted to investigate the differences in psychopathology and coping strategies among internet addictors, over users and non addictors in high school students. Subjects were 273 high school students in Seoul city. Self rating questionnaires included demographic data, Young’s Internet Addiction Scale, SCL-90-R, Beck Depression Inventory, Spielberger State-Trait Anxiety Inventory, and The Way of Coping Strategy. Subjects were classified into 3 groups (addiction, over use, non addiction) by Internet Addiction Scale score. Prevalence of internet addiction was 4.3% and male adolescents were more addictive than female. Students who were mainly involved with internet chatting or game showed higher internet addiction score. The addiction group and over use group showed higher level of somatization, obsession, interpersonal sensitivity, depression, anxiety, hostility, and paranoia than non-addicted group. Addiction group and over use group used passive coping strategies more frequently in the stressful situation than nonaddicted group. Also, the regression analysis for finding out causal factors that predicts internet addiction showed that emotion relieving strategy were important variable which predict internet addiction. Interpersonal sensitivity and emotion relieving coping strategy was important to predict addiction. This study showed that problematic internet use was closely associated with psychopathology and psychiatric comorbidity. And high interpersonal sensitivity and emotion relieving coping strategy were related with internet addiction in adolescence.

적외선 체열촬영을 이용한 온천요법에 관한 임상적 연구

이정민 ( Jung Min Lee ),뱍인선 ( In Sun Park ),안택원 ( Taek Won Ahn ),홍서영 ( Seo Young Hong ) 한방재활의학과학회 2012 한방재활의학과학회지 Vol.22 No.1

Objectives :The purpose of this study was to investigate the influence of balneotherapy on the changes of DITI(digital infrared thermal imaging). Methods :This study was carried out on 27 patients. They went through balneotherapy with high pressure under water shower(15 min.) and whole body bathing in neutral or hot water between 32 to 40 ℃(15 min.). DITI was measured at before and after the treatment. And then the data was analyzed. Results :1. In cold hypersensitivity of hands group, temperature on PC8 rose and difference between LU4 and PC8 decreased(p<0.05)(Fig. 1, Table Ⅱ). 2. In cold hypersensitivity of feet group, temperature on LR3 rose and difference between ST32 and LR3 decreased(p<0.05)(Fig. 2, Table Ⅱ). 3. In shangrexiahanzheng(上熱下寒證) group, there were no significant changes on CV17, CV6 and difference between CV17 and CV6(Fig. 3, Table Ⅱ). Conclusions :These results demonstrated that balneotherapy has clinical effects on cold hypersensitivity of hands and feet. And further studies are required to apply the balneotherapy in order to cure various diseases in the future.

열처리에 의한 Morganella morganii와 Photobacterium phosphoreum 유래 Histidine Decarboxylase의 불활성화

박원민(Won-Min Pak),김꽃봉우리(Koth-Bong-Woo-Ri Kim),김민지(Min-Ji Kim),박지혜(Ji-Hye Park),배난영(Nan-Young Bae),박선희(Sun-Hee Park),안동현(Dong-Hyun Ahn) 한국식품영양과학회 2016 한국식품영양과학회지 Vol.45 No.3

Histamine을 생성하는 Morganella morganii와 Photobacterium phosphoreum으로부터 crude histidine decarboxylase(HDC)를 추출하여 65~121°C로 열처리한 다음 균의 생육 및 효소 활성 변화에 대해 살펴보았다. 그 결과 M. morganii와 P. phosphoreum은 모든 열처리 조건에서 비 가열 처리구와 비교 시 균의 생육이 저해됨을 확인하였다. M. morganii와 P. phosphoreum 유래 HDC의 효소 활성은 65°C에서 90% 이상의 효소 활성이 저해됨을 확인하였고, 온도가 증가함에 따라 유의적으로 활성이 억제되는 것으로 나타났다. SDS-PAGE 결과에서는 65~100°C 범위에서 비가열 처리구와 비교 시 조효소액의 단백질 패턴의 변화가 크지 않았으나, 121°C에서 단백질 band의 강도가 크게 약해졌다. Native-PAGE에서는 65°C 처리 조건에서부터 단백질 패턴의 변화가 크게 나타났다. 따라서 가열처리(65~121°C)는 histamine 생성균인 M. morganii와 P. phosphoreum의 생육을 억제할 뿐만 아니라 HDC의 효소 활성도가 저해됨을 확인하여, 식품산업에서 적용되고 있는 열처리 조건에서 histamine 생성 억제에 큰 효과가 있는 것으로 생각한다. This study was performed to investigate the effects of various thermal treatments on the growth of Morganella morganii and Photobacterium phosphoreum and activity of crude histidine decarboxylase (HDC) obtained from M. morganii and P. phosphoreum. Crude HDC and the two strains were treated at 65°C/30 min, 80°C/10 min, 100°C/10 min, and 121°C/10 min. Activity of crude HDC decreased with increasing temperature. Viable cells counts of M. morganii and P. phosphoreum were not detected in any heated samples. SDS-PAGE patterns of heated HDC did not show significant differences up to 100°C. However, at 121°C, protein band intensity was weakened. In native-PAGE, there was a major change in the pattern of HDC at 65°C. These results suggest that thermal treatment can help to reduce histamine production by reducing HDC activity and growth of M. morganii and P. phosphoreum.

반응표면분석법을 이용한 대추잎 항산화물질의 에탄올추출조건 최적화

민들레(Dul-Lae Min),임석원(Seokwon Lim),안준배(Jun-Bae Ahn),최영진(Young Jin Choi) 한국식품과학회 2010 한국식품과학회지 Vol.42 No.6

대추잎 항산화 물질의 고효율 추출을 위한 에탄올 용매추출조건을 반응표면분석법을 사용하여 최적화하였다. Box-Behnken design에 따라 추출공정 조작변수(온도, 시간, 에탄올 농도)를 독립변수로, 이에 따라 영향을 받는 종속변수(총 폴리페놀 함량, 총 플라보노이드 함량, 전자공여능)를 설정하여 실험하였다. 추출물의 총 폴리페놀 함량과 총 플라보노이드 함량은 시간과 온도의 영향을 거의 받지 않으며, 용매비가 높을수록 증가하다가 최고점을 보인 후 다시 감소하는 경향을 나타내었다. 전자공여능 또한 시간과 온도의 영향보다는 용매비에 영향을 많이 받는데, 에탄올 농도가 높을수록 전자공여능이 높게 측정되었다. 추출물의 특성을 모두 만족시키는 최적 추출조건 범위 내에서 임의의 조작조건(온도 45℃, 시간 15분, 에탄올 농도 45%)을 설정하였다. 최적조건에서 예측값과 실험값을 비교한 결과, 유사한 값을 보여주어 회귀식이 신뢰할 수 있음을 알 수 있었다. The leaves of Zizyphus jujuba have been used for various purposes including medicine and nutrition. In this study, the conditions for the ethanol extraction of antioxidant from Zizyphus jujuba were optimized using response surface methodology (RSM). A Box-Behnken design containing 15 experimental runs with three replicates was employed to study the effects of solvent extraction conditions such as extraction temperature (℃, X<SUB>1</SUB>), extraction time (min, X<SUB>2</SUB>), and ethanol concentration (%, X<SUB>3</SUB>) on the extraction yield of antioxidants from Zizyphus jujuba. The yields of total polyphenols and total flavonoid, and electron donating activity (EDA) were considered as response variables. The second-order polynomial model gave a satisfactory description of the experimental results showing different patterns of extraction conditions with variation in the linear, quadratic, and interaction effects of the independent variables. Based on four-dimensional RSM, one of the optimized sets of conditions was 45% ethanol, 45℃, and an extraction time of 15 min. Under the optimal conditions, the predicted values were 177.64 mg/g dry basis, 35.99 mg/g dry basis, and 86.14% Vit.C equivalents for total polyphenols, total flavonoids, and EDA, respectively. The experimental values showed good agreements with the predicted values.

직접 검화법을 이용한 조제분유의 콜레스테롤 분석법 개발

김진만,박정민,윤태형,임동길,윤창용,정자영,정인식,곽병만,안장혁,Kim, Jin-Man,Park, Jung-Min,Yoon, Tae-Hyung,Leem, Dong-Gil,Yoon, Chang-Yong,Jeong, Ja-Young,Jeong, In-Seek,Kwak, Byung-Man,Ahn, Jang-Hyuk 한국축산식품학회 2011 한국축산식품학회지 Vol.31 No.6

본 연구에서는 조제분유 중의 콜레스테롤을 신속하고 정확하게 분석하기 위해 지방 추출 과정을 거치지 않는 직접 검화 방법을 선택하여 분석법 개발을 시도하였다. 조제분유 분말시료를 직접 검화 수기에 취하여 검화 온도, 검화 시간, KOH 농도의 3가지 인자에 대해 콜레스테롤 회수율이 가장 양호하게 나타나는 최적 검화조건을 확립하고, 검화 후 수세과정에서 액액 분배가 용이한 용매 조건도 확립하였다. 또한 콜레스테롤 피크의 완전한 분리를 위한 적정 기기 조건을 확립하였다. 그 결과, 시료 약 2 g에 16 M-KOH 10 mL를 넣고 $90^{\circ}C$에서 60분 가열하여 검화한 후 diethyl ether로 3회 추출하고 hexane을 최종시험용액으로 하여 기기분석을 했을 때의 회수율이 98.80%로서 가장 양호하게 나타났다. 본 연구를 통해 개발된 조제분유의 효율적인 액액분배 및 직접가열 검화법은 일원배치 분산법에 의해 유화가공식품의 콜레스테롤 분석법으로 유효성이 검증되었으며, 아울러 개발된 전처리 방법 및 기기 분석 조건을 활용해 다양한 분석 기관에서 신속 정확하고 효율적인 콜레스테롤 분석을 수행할 수 있을 것으로 기대된다. 또한 산업체의 품질관리 및 검증기관에서 필요시 모니터링에 적극 활용 가능할 것으로 사료되며, 이를 통해 유화가공식품 류의 함량표시 및 규격관리의 정확성과 효율성 증대에 기여하여 제조업체의 정확하고도 효과적인 품질 및 안전성 확보에 기여할 수 있을 것으로 판단된다. 특히 위해 물질에 대한 정확한 함량 판단이 중요한 조제분유 등의 영 유아용 식품의 안전성 확보에 지대한 공헌을 할 수 있을 것으로 기대된다. An improved cholesterol analysis method was developed for powdered infant formula by gas chromatographic separation after liquid-liquid extraction and partition. In the official Korea Food Standard method for cholesterol analysis, the water phase and solvent phase were not well separated in the case of emulsified foods such as powdered infant formulas and baby foods. For the rapid and simple sample preparation method, an optimized direct saponification condition was established for heating temperature, heating time, and KOH concentration. From the results, the optimum conditions were as follows: heating temperature $90^{\circ}C$, heating time 60 min, and 16 M KOH 10 mL for a 2 g infant formula sample; improved separation condition for gas chromatography was as follows: the initial oven condition was $250^{\circ}C$ for 25 min, the oven temperature was increased to $290^{\circ}C$ by $10^{\circ}C$/min ratio, and finally the oven temperature remained at $290^{\circ}C$for 9 min. The developed method could be implemented for the study of cholesterol, providing the advantages of reduced inspection time and cost in emulsified foods such as infant formula.

웹문서의 텍스트 제시 유형에 따른 독해력의 비교

안영식,김영환,문창민 한국교육정보미디어학회 2003 교육정보미디어연구 Vol.9 No.3

학습의 기본적인 활동인 '읽기(Reading)'는 최근 인터넷의 확산으로 웹문서를 통해서 이루어지는 경우가 많다. 하지만 웹문서는 매우 다양하기 때문에 어떠한 웹문서가 '읽기'에 가장 적합한가를 고려해볼 필요가 있다. 따라서 본 연구는 웹문서에 따라 학습의 기본 능력인 '읽기'가 어떻게 다른가를 살펴봄으로써 '읽기'에 효과적인 웹문서 디자인의 지침을 제공하고자 한다. 먼저 다양한 웹문서를 유형화하기 위해 텍스트 위주로 운영되는 30개의 웹문서를 조사하여 웹문서 유형을 결정짓는 변인을 줄 길이와 글자 크기, 화면 밀도로 정하였고 이 변인들을 조합하여 9개의 웹문서 유형을 만들었다. 그 후 9개의 유형에 따라 독해력(Readability) 검사를 실시하여 '읽기'에 어떤 차이가 나는지 알아보았다. 연구를 통해서 웹문서(15인치 기준)에 있는 텍스트의 줄 길이와 글자 크기간에 독해력에 대한 교호작용은 일단 없는 것으로 나타났다. 텍스트의 줄 길이만을 변인으로 하였을 때, 17∼18cm, 21∼22cm, 26∼27cm 중 가장 짧은 17∼18cm에서의 독해력 점수가 가장 높았다. 텍스트의 글자 크기는 9p, 10p, 12p 중 어떤 크기를 사용하더라도 독해력에는 관계가 없었다. 화면 밀도는 기존의 분류를 바탕으로 16%이하(저밀도), 16∼32%(중), 32% 이상(고)으로 나누어 독해력을 알아본 결과 중밀도에서 가장 독해력이 높았다. This study was aimed to find the correlation between web-text presentation patterns and readability. The investigation into several variables determining web-text presentation patterns was made. Of several variables, line length and font size were major variables. Line length as the first variable could be classified into three types(17.4cm, 21.3cm, 26.4cm) and font size as the second variable could be classified into three types(9p, 10p, 12p). The 9 web-text presentation patterns were made by 3(1st variable)×3(2nd variable). CRT density was added as the third variable and was applied to the 9 web-text. How these three variables influence the readablity was found by Two-way ANOVA. Reading result test and reading process test went abreast to measure the readablity influenced by these three variables. Major findings from this study were as follows. 1. There was no interaction effect between line length and font size in web-text. It meaned that any combinations of specific line length with specific font size in web-tex could not influence improving readability. 2. Readability improved when the line length in web-text was 17∼18cm(17.4cm as average). It meaned that designing line length in web-text to be 60∼64% could enhance readablity. 3. Any font size among 9p, 10p, 12p could not influence improving readability. 4. When the level of web-text density in web-text was presented in moderate density, significant result was produced statistically. Moderate density means 16.0%∼ 32%(26.6%∼28.0% in this study) of a full web-text. A ccording to the results of this study, it is suggested that to design line length to be 60∼64% in full width of web-text and to design density to be 16.0%∼32%(26.6%∼ 28.0% in this study) can enhance readablity in web-text.

Hydrotalcite의 製造條件에 關한 硏究

안세민,신화우,최광식,이광표,장영수 원광대학교 식품약품안전성연구소 1993 食品藥品安全性硏究 Vol.6 No.-

Hydrotalcite is mainly used as a antacid and adsorbent. It is Well Known that the yield of hydrotalcite produced is greatly affected by the preparation conbition such as the reactant concetration, reaction temperature, reaction time, mole ratio of reactants and grying tepeeature, etc. the purpose of this study is to investigate the optimum preparation condition of hydrotalcite. Arandomived complete block design suggested by G.E.P.Box and K.B. Wilson was appliedfor this purpose. Hydrotalcite was prepared by reacting sodium carbonate. Magnesium oxide and Aluminum sulfate solutions in this study. The optimum preparation condition of hydrotalcite obtained from this study is as follows: 1) The reaction temperature range is 48-63℃ 2) The concentration of reactant solutions is about 20% 3) The optimum mole-ratio (MgO/Al. sulfate) is 7.35-8.1. 4) The reacting time tatge is 10-11 min.. 5) The drying temperature range is 78-82℃ The outcome of D.S.C. indicated a desolvation of hydrotalcite occured at about 98℃ The dehydration of the compound ceased at about 250℃, and the decarboxylation ceased at about 446℃ The physical and chemical properties of hydrotalcite as medicine were studied by use of chemical analysis, bulk volume test and acid consuming capacity measurements.

高周波 運續 熱處理한 PC 鐵線의 腐蝕機構

安英敏,吳應煥,黃龍吉 동아대학교 공과대학 부설 한국자원개발연구소 1989 硏究報告 Vol.13 No.1

This study has been carried out to investigated into corrosion of PC steel wires, heat-treated AISI1022 and AISI10B32 at set temperature by high frequency induction continuation heat-treatment, that was deposited in city water, seawater, 0.75% H₂SO₄ solution and NH₄SCN aqueous solution for the 20days.

환자복 디자인 개선에 관한 연구

안민영;서미아;박재옥;이연희 한양대학교 2004 韓國 生活 科學 硏究 Vol.- No.24

The purpose of this project was to find out design elements of patients' uniform which satisfied needs and wants of patients and nurses. Data were obtained via a self-administered questionnaire from 127 patients who were admitted and nurses who employed to Hanyang University Hospital. The questionnaires were composed of dissatisfaction of exiting patient's uniform, evaluation criteria, design preference, and demographic factors. For data analysis, Descriptive statistics, one-way ANOVA, and Duncan test were employed. The results of this study were as follows; 1. Patients and nurses considered important design elements of neckline, sleeve length, waistband of the pants, and number of pocket. 2. There were differences in dissatisfaction of exiting patient's uniform related to role types. Patients considered factors related to movement such as comfort, easy to dress more importantly, while nurses considered factors related to affairs such as convenient for medical treatment, classification of size, and colorfastness to the laundry more importantly. 3. There was a significant difference in evaluation criteria of patients' uniform related to role types. Nurses considered more important expressive and economic criteria, while patients considered more important functional criteria than others. 4. There was a difference in deign preference of patients' uniform related to role types. Patients preferred uniform design which composed of U-neckline, sleeve of three-quarter length, pants of ankle length, elastic-band with a drawstring, and colors of pink and light green, while nurses preferred design which composed of round neckline, long sleeve length, pants of floor length, and colors of light green and light blue.