• Title/Summary/Keyword: 피로특성

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Application of Ultrasonic Nano Crystal Surface Modification into Nitinol Stent Wire to Improve Mechanical Characteristics (나이티놀 스텐트 와이어의 기계적 특성 향상을 위한 초음파 나노표면 개질 처리에 대한 연구)

  • Kim, Sang-Ho;Suh, Tae-Suk;Lee, Chang-Soon;Park, In-Gyu;Cho, In-Sik;Pyoun, Young-Shik;Kim, Seong-Hyeon
    • Progress in Medical Physics
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    • v.20 no.2
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    • pp.80-87
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    • 2009
  • Phase transformation, superelastic characteristics and variation of surface residual stress were studied for Nitinol shape memory alloy through application of UNSM technology, and life extension methods of stent were also studied by using elastic resilience and corrosion resistance. Nitinol wire of ${\phi}1.778$ mm showed similar surface roughness before and after UNSM treatment, but drawing traces and micro defects were all removed by UNSM treatment. It also changed the surface residual stress from tensile to compressive values, and XRD result showed less intensive austenite peak and clear martensite and additional R-phase peaks after UNSM treatment. Fatigue resistance could be greatly improved through removal of surface defects and rearrangement of surface residual stress from tensile to compressive state, and development of surface modification system to improve not only bio-compatability but also resistance to corrosion and wear will make it possible to develop vascular stent which can be used for circulating system diseases which run first cause of death of recent Koreans.

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A Study on the Dental Hygienists' Reactions to Noise When Occurred in Dental Clinic (치과병원에서 발생하는 소음에 대한 치과위생사의 반응)

  • Choi, Mi-Suk;Ji, Dong-Ha
    • Journal of dental hygiene science
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    • v.9 no.4
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    • pp.453-459
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    • 2009
  • The purposes of this research were to evaluate the relationships of between characteristics of noise and annoyance of dental hygienist by noise in dental clinic. To investigate the dental clinic workers' reactions to noise when occurred in dental clinic, the noise level test in dental clinic and questionnaire were taken. As a result of noise evaluation, It shows that the range of noise level was 67.7~78.3dB(A) and frequency was very high (more than 4KHz). It's seem to be begins occurrence of stamina-loss, contraction of peripheral blood vessel, decrease of adrenocortical hormones. Most of respondents were affected by noise: 67% of respondents were nervous about noise and the rest of respondents were bearable. Analysis by NR-curve showed that it was exceed the noise permit level in working space. As a result of correlation - test, the more exposed dental hygienist to noise, the more felt the unpleasantness and fatigue. It's hard to sufficient explanation to patients about the dental treatment. So it's thoughts that insufficient explanation will negative impact on the patients' satisfaction and increase competitiveness in dental clinics. To remedy a unpleasantness and fatigue of noise in dental hygienist, it's considered that making an offer the ear protection and choosing the low noise-vib. equipment and using the masking effect. Therefore, It can be provide a pleasant working environment with dental hygienist and It will have a great advantage to dental clinics to improve their competitiveness.

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Physicochemical Properties, Free Sugar and Volatile Compounds of Korean Citrons Cultivated in Different Areas (산지별 유자의 이화학적 특성, 유리당 및 향기성분)

  • Lee, Soo-Jung;Shin, Jung-Hye;Kang, Min-Jung;Jeong, Chang-Ho;Ju, Jong-Chan;Sung, Nak-Ju
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.1
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    • pp.92-98
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    • 2010
  • Physicochemical properties, free sugar and volatile flavor compounds of citrons harvested in different cultivation areas, such as Geoje, Goseong, Goheung, and Namhae, were analyzed and compared. Total weight of citron, ranging from 107.97 g to 154.86 g, was significantly different according to producing area. Weight ratio of flesh to whole citron was higher than one of peel in citron produced from Geoje, Goheung-improved, or Namhae-native. Citron size was the highest in Namhae-native citron, but the color of peel was significantly the higher in Goheung-native and its improved citron. In the peel of citron, hardness of citron produced from Geoje was the strongest (2337.13 $cm/kg^2$) whereas citron produced from Goseong (1592.38 $cm/kg^2$) showed the softest hardness. Moisture content was 85.35~87.81 g/100 g and ash was contained below 0.8 g/100 g in flesh of all samples. Although crude fiber content in Geoje ctiron was significantly the lowest in the peel, peel was 1.88~2.60 times higher than flesh. The order of sugar content seemed to be fructose> glucose> sucrose in all citrons, and content of fructose or glucose was higher in peel than flesh. Content of total sugar was 8.44~12.19 g/100 g in citron, and contents of improved citrons from Goheung and Namhae were significantly higher than those of native citrons. In addition, major volatile compounds were dl-limonene (59.52~74.30%) and $\gamma$-terpinene (5.60~7.88%) among 15 kinds of volatile compounds identified from citron peel. These results suggested that physicochemical properties and volatile flavor compounds of citrons showed some differences with regard to producing areas.

Characteristics of Premenstrual Changes in Patients with Affective Disorder (정서장애 환자의 월경전기변화 특성)

  • Ko, Young-Hoon;Joe, Sook-Haeng;Suh, Kwang-Yun
    • Korean Journal of Psychosomatic Medicine
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    • v.7 no.1
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    • pp.103-115
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    • 1999
  • Objectives : A large of studies have found an association between premenstrual syndrome and affective disorder, in particular, depression. Some studies have reported that women with depressive disorders may experience menstrual cycle-associated changes in the severity of their symptoms. This study was designed to compare the characteristics of premenstrual changes between control group and affective patient group, and to assess possible risk factors for premenstrual changes in patients. Methods : Eighty normal controls and eighty outpatients given maintenance therapy with fixed dose for at least more than four weeks were asked to complete questionnaires on menstrual history, obstetric-gynecological history, and functional impairment. In addition, to compare the characteristics of premenstrual changes, 16 items based on DSM-IV criteria A for premenstrual dysphoric disorder were rated on the following scale : 0(no change), 1(mild), 2(moderate), 3(severe). Moderate or severe change in each item was considered as premenstrual change and the subjects who reported more than one premenstrual change were defined as premenstrual change group. Results : The results were as follows : 1) The percentage of premenstrual change group was 32.6% in patient group and 50% in control group. 2) Frequently reported premenstrual changes were as follows in control group : breast tenderness; anger ; affective liability ; lethargy, easy fatigability, or marked lack of energy ; abdominal pain or discomfort. In patients, the mood or behavioral changes were frequently reported. The changes were as follows : lethargy, easy fatigability, or marked lack of energy ; change in appetite; affective liability ; sense of difficulty in concentrating : hypersomnia or insomnia. 3) In the premenstrual change group, the patients with only mood or behavioral changes were significantly more than those with only physical changes or both changes. 4) The severity of functional impairment was significantly correlated with the frequency of mood or behavioral changes in patients. 5) There were no significant differences in menstrual characteristics between patients with premenstrual changes and patients without them except the severity of dysmenorrhea. And the severity of dysmenorrhea was correlated with the frequency of premenstrual change. Conclusion : The proportion of patients with affective disorder, who reported moderate-to-severe premenstrual changes, experiencing mood or behavioral changes larger than those experiencing physical changes during premenstrual period. It is possible that some patients with affective disorder, who reported premenstrual mood or behavioral changes, suffer from coexisting premenstrual syndrome with affective disorder or premenstrual exacerbation of affective disorder. Since the more premenstrual changes, the severer functional impairment, the patients reporting mood or behavioral disturbance in premenstrual period should be carefully evaluated, and appropriate therapeutic stategies might be considered.

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Quality Characteristics of Takju Fermentation by Addition of Chestnut Peel Powder (율피가루를 첨가한 탁주의 품질 특성)

  • Jeong Jin-Woong;Park Kee-Jai;Kim Myung-Ho;Kim Dong-Soo
    • Food Science and Preservation
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    • v.13 no.3
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    • pp.329-336
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    • 2006
  • The characteristics of mash qualities of takju prepared by addition of chestnut peel powder(5%, 10%, 20% and 30% per steamed rice) were investigated during fermentation. That is, in all fermentation periods, changes of pit total acid, organic acids, solids, amino nitrogen, total sugar and reducing sugar, microorganisms, alcohol and color were determined and analyzed. There was significant differences in characteristics of mash qualities by addition of chestnut peel powder. In general, contents of total acid, organic acids, amino nitrogen, total sugar, reducing sugar and ethanol of takju added with chestnut peel powder were lower than those of steamed rice only, whereas solid contents was higher. But ethanol content of takju added with 5% of chestnut peel powder after 8 days of fermentation was 9.6% which was similar to that of takju prepared by addition of steamed lice only. Also, microbial populations such as total viable cells, yeast and lactic acid bacteria of the treatments were increased to about $10^8CFU/mL$ after 2 days of fermentation and then decreased gradually. In the beginning stage of fermentation color differences value of the treatments were $1.99{\sim}10.27$, and the differentials reduced gradually during fermentation.

A Study on the Health Status and Dietary Intake of Rural Elderly Women in Kyeonggi Province (경기도 농촌 지역 여성노인의 건강 및 식생활 실태조사)

  • 이종현;김민선;이연숙;박양자
    • Korean Journal of Rural Living Science
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    • v.5 no.2
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    • pp.135-144
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    • 1994
  • This study was carried out to investigate health status and nutritional status based on dietary intake and food habit of elderly women in rural area of Keyonggi Province. The subject of this study were 133 elderly women aged 60 and over and interviewed with a questionaire. Main result was as follows : 1) Health score based on modified Cornell Medical Index, CMI(45 out of 195 items) was the average $29.1\pm6.8$ and was not significantly different with family size educational level and farmwork participation. In age, 44.0% of the subject in 60~65 years old was low score of CMI(11~25), but 50% of the subject in older than 80 years old was high score(33~44). The subject with disease was 82% and disease of musculoskeletal system was main type. 2) Dietary intake data obtained by a semiquantitative food frequency questionaire showed the average daily intake of energy, protein, Ca, retinol and riboflavin was lower than RDA Daily energy, protein and Ca intake was individually 84%, 67% and 55.1%. It was retinol that was the least sufficient as 49.1% of RDA. 3) The relation between CMI score(divided into three level : low, middle and high) showed low level was significantly different with others according to daily intake of energy, protein, retinol, thiamin, riboflavin and ascorbic acid. The correlation between CMI score and all nutrient intake were highly significant (p<0.001), thus we knew that health status was affected importantly by nutrient intake. 4) Family size, educational level and age showed not significant correlation with all nutrient intake. 5) In food habit, 84.8% of the subject had regular mealtime and 14.4% were skip meal sometimes. The main reason of skip meal was a poor appetite. Preference for salty taste of subject was insufficiently salty of somewhat salty. Preference for fishes and meats showed the subject consumed fishes more than meats, but 23.5% of the subject didn't consume both. The subject eaten supplement was 38.3%.

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Change in Health Behaviors of Patients Before and After Stroke (뇌졸중 환자의 발병전후 건강행위의 변화)

  • Jang, Sang-Hyeon;Kang, Pock-Soo;Lee, Kyeong-Soo;Kim, Seok-Beom;Yun, Sung-Ho
    • Journal of agricultural medicine and community health
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    • v.27 no.1
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    • pp.9-19
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    • 2002
  • This study was conducted to compare the health behaviors of patient s before and after a stroke and propose health education program to reduce risk factors related to stroke recurrence. Data were collected from eighty- eight stroke patients registered at the Gyeongju-si Health Center between July 1, to August 30, 1999, by interviewing patients from a prepared structured questionnaire, which included questions on that patients ' general characteristics, health- related behaviors, family-related characteristics, and pre- and post - stroke health status. Smoking rate of 51.1% before stroke reduced to 25.0% after stroke; drinking rate of 52.3% before stroke reduced to 17.0% after stroke; daily smoking amount of 20.1 packs per day before stroke significantly reduced to 14.9 packs per day after stroke; and daily drinking amount of 92.4ml before stroke significantly reduced to 23.7ml after stroke. Smoking rate according to sex showed a marked decrease in the male subjects, but 31.6% still smoked even after their stroke. Among the female subjects, smoking rate of 16.1% before stroke reduced to 12.9% after stroke. Observation of the change in health- related behaviors of stroke patient s showed significant change in smoking rate, drinking rate and intake of regular meals etc. of patient s with a spouse and patients who received preventive health education. Health education on quitting smoking, temperance, low fat diet, exercise and regular meals for stroke patient s are needed, and public and private organizations can do their part in development and providing continuing health education programs and health education.

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Unmet Medical Service Needs in Family Caregivers of Terminal Cancer Patients (말기암환자 가족간병인의 미충족 의료 분석)

  • Shin, Woong Jae;Hwang, Sun Wook;Hwang, In Cheol;Choi, Youn Seon;Lee, Yong Joo;Kim, Young Sung;Shin, Ji Sung;Choi, Young Ho;Rim, Da Won;Kim, Han Sook
    • Journal of Hospice and Palliative Care
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    • v.19 no.2
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    • pp.163-169
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    • 2016
  • Purpose: The unmet medical service needs of caregivers critically influence their caring for terminal cancer patients, but not much research has been done in this regard. Thus, the purpose of this study is to investigate the association between caregivers' characteristics and their unmet medical service needs. Methods: The survey was conducted with 109 family caregivers of terminal cancer patients admitted to four hospice units. The data were collected from March 2014 through December 2014 using a structured questionnaire. The unmet medical service needs were measured using 14 items which were adopted and modified by authors. Results: Seven areas of unmet medical service needs were shown to be significant. A well-educated group showed stronger needs for counsel about cancer screening and complementary-alternative medicine and health supplement food. A never-smoked group was identified with less need for sexual dysfunction counsel. Counsel about family and personal relations was more necessary for current drinkers and current workers, and less necessary for the married. Insurance counsel was more needed for a no-religion group. Occupation counsel was less necessary for healthy patients. Financial support was less necessary for the married group. Conclusion: Based on the results, it is highly recommended to further investigate the unmet medical service needs of family caregivers for terminal cancer patients and causes of the unmet needs.

Health Assessment of Shift Workers in a Automobile Manufacturing Plant (자동차공장 교대작업 근로자들의 건강상태평가)

  • Lee, Jung-Jeung;Chung, Jong-Hak
    • Journal of Preventive Medicine and Public Health
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    • v.28 no.1 s.49
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    • pp.103-121
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    • 1995
  • An investigation on psychophysiological health and social well-being of shift workers been carried out on workers of a automobile manufacturing plant in Ulsan, for 1 month from April, 1993. This cross-sectional survey compared shift workers(n=544) with day workers(n=115). Each subject completed a questionnaire about his personal habit, background, shift schedule, sleep and eating patterns, subjective digestive symptom and psychological well-being and distress using the General Well-Being Schedule(GWB) by self administrated questionnaire that was developed for the U.S. Health and Nutrition Examination Surveys (HANES I). Chi-square analysis was used for discontinuous data and the t-test was used for continous data to determine whether differences noted between the two groups. In terms of sleep quality, a greater percentage of shift workers frequently had trouble getting back to sleep once awakend(p<0.01), and a greater percentage of shift workers awakend tired or sleepy frequently more often than day workers(p<0.05). In rating the quality of their sleep, more shift workers rated their sleep fair to poor than day workers, and greater percentage of shift workers felt tired or sleepy at work two or more times per week(p<0.01) and a much higher percentage of shift workers felt tired or sleepy after work every days(p<0.01). In terms of sleep patterns, a much higher percentage of day workers reported uninterrupted sleep per 24hours than shift workers. The shift workers reported different eating patterns from day workers but there were no statistically significant and rate of their appetite. Thirteen percent of day workers reported the best appetite but only 6.6% of shift workers had the best appetite. The gastric complaints is more frequent in shift workers than day workers(p<0.01). Among subscores in General Well-Being Schedule, anxiety, depression, positive well-being and vitality subscale of shift workers were lower than those of day workers(p<0.05) and general health and self control subscale of shift workers were lower than .those of day workers but there were no statistical significant difference. Based on these study result, it could be concluded that the shift work has significant effects on some psychophysiological conditions of the workers.

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Characteristic Properties of Fucoidan Sulfate Purified from Gompi, Ecklonia stolonifera (곰피에서 정제한 Fucoidan Sulfate의 특성)

  • Lee, Hong-Soo;Jin, Sung-Hyun;Kim, Hee-Sook;Ryu, Byung-Ho
    • Korean Journal of Food Science and Technology
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    • v.27 no.5
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    • pp.716-723
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    • 1995
  • The fucoidan purified from Korean brown seaweed, Ecklonia stolonifera was characterized on molecular structure and blood anticoagulant activities. Extraction was conducted at $100^{\circ}C$ with water and repeated twice. The crude fucodian was 151.1g out of 20.0 kg of Ecklonia stolonifera. The Fucoidan-1, which was purified from crude fucoidan using calcium chloride and cetyl pyridium chloride (CPC), was 35.2% against crude fucoidan. Fucoidan-5 was obtained approximately 28.1% from Fucoidan-1 through DEAE-Toyopearl 650 M ion-exchange column chromatography and showed one band by cellulose acetate electrophoresis. The molecular weight of Fucoidan-5 was estimated to be about 21,000∼23,000 dalton by Sephacryl S-300 gel filtration chromatography. Fucoidan-5 consists of 35.7% of fucose and 4.3% of galactose and the molar ratio of fucose and sulfate was about one to one. IR spectrum of Fucoidan-5 showed absorption at $1240\;cm^{-1}\;and\;850\;cm^{-1}$ and specific rotation value, $[\alpha]$, was $[\alpha]$. These results suggests that the sulfate maybe bind at $C_{4}$ carbon on ${\alpha}-L-fucose$. Gas chromatograph of methyl alditol acetate revealed that Fucoidan-5 is a fucose containing sulfated polysaccharide with $({\alpha}l-2)\;or\;({\alpha}l-2)$ glycosidic linkage. Anti-thrombin activity of the Fucoidan-5 was estimated as 1.4 time stronger than heparin. From above results, the purification methods using CPC and ion exchange chromatography is effective tools for obtaining highly purified fucoidan from Gompi, Ecklonia stolonifera.

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