• Title/Summary/Keyword: systematic research

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Electronic Structure and Si L2,3-edge X-ray Raman Scattering Spectra for SiO2 Polymorphs: Insights from Quantum Chemical Calculations (양자화학계산을 이용한 SiO2 동질이상의 전자 구조와 Si L2,3-edge X-선 라만 산란 스펙트럼 분석)

  • Kim, Yong-Hyun;Yi, Yoo Soo;Lee, Sung Keun
    • Korean Journal of Mineralogy and Petrology
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    • v.33 no.1
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    • pp.1-10
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    • 2020
  • The atomic structures of silicate liquids at high pressure provide insights into the transport properties including thermal conductivities or elemental partitioning behavior between rocks and magmas in Earth's interior. Whereas the local electronic structure around silicon may vary with the arrangement of the nearby oxygens, the detailed nature of such relationship remains to be established. Here, we explored the atomic origin of the pressure-induced changes in the electronic structure around silicon by calculating the partial electronic density of states and L3-edge X-ray absorption spectra of SiO2 polymorphs. The result showed that the Si PDOS at the conduction band varies with the crystal structure and local atomic environments. Particularly, d-orbital showed the distinct features at 108 and 130 eV upon the changes in the coordination number of Si. Calculated Si XAS spectra showed features due to the s,d-orbitals at the conduction band and varied similarly with those observed in s,d-orbitals upon changes in the crystal structures. The calculated Si XAS spectrum for α-quartz was analogous to the experimental Si XRS spectrum for SiO2 glass, implying the overall similarities in the local atomic environments around the Si. The edge energies at the center of gravity of XAS spectra were closely related to the Si-O distance, thus showing the systematic changes upon densification. Current results suggest that the Si L2,3-edge XRS, sensitive probe of the Si-O distance, would be useful in unveiling the densification mechanism of silicate glasses and melts at high pressure.

Geochemistry and Genesis of Hydrothermal Cu Deposits in the Gyeongsang Basin, Korea : Hwacheon-ri Mineralized Area (경상분지내 열수동광상의 지화학 및 성인연구 : 화천리지역 광화대)

  • So, Chil-Sup;Choi, Sang-Hoon;Yun, Seong-Taek
    • Economic and Environmental Geology
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    • v.28 no.4
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    • pp.337-350
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    • 1995
  • The Hwacheon-ri mineralized area is located within the Cretaceous Gyeongsang Basin of the Korean peninsula. The mineralized area includes the Hwacheon, Daeweon, Kuryong and Cheongryong mines. Each of these mines occurs along copper-bearing hydrothermal quartz veins that crosscut late Cretaceous volcanic rocks, although some disseminated ores in host rocks also exist locally. Mineralization can be separated into three distinct stages (I, II, and III) which developed along preexisting fracture zones. Stage I is ore-bearing, whereas stages II and III are barren. The main phase of ore mineralization, stage I, can be classified into three substages (Ia, Ib and Ic) based on ore mineral assemblages and textures. Substage Ia is characterized by pyrite-arsenopyrite-molybdenite-pyrrhotite assemblage and is most common at the Hwacheon deposit. Substage Ib is represented by main precipitation of Cu, Zn, and Pb minerals. Substage Ic is characteristic of hematite occurrence and is shown only at the Kuryong and Cheongryong deposits. Some differences in the ore mineralization at each mine in the area suggest that the evolution of hydrothermal fluids in the area varied in space (both vertically and horizontally) with respect to igneous rocks relating the ore mineralization. Fluid inclusion data show that stage I ore mineralization mainly occurred at temperatures between ${\approx}350^{\circ}$ and ${\approx}200^{\circ}C$ from fluids with salinities between 9.2 and 0.5 wt.% eq. NaCl. In the waning period of substage Ia, the high temperature and salinity fluid gave way to progressively cooler, more dilute fluids of later substage Ib and Ic (down to $200^{\circ}C$, 0 wt.% NaCl). There is a systematic decrease in the calculated ${\delta}^{18}O_{H2O}$ values with paragenetic time in the Hwacheon-ri hydrothermal system from values of ${\approx}2.7$‰ for substage Ia, through ${\approx}-2.8$‰ for substage Ib, to ${\approx}-9.9$‰ for substage Ic. The ${\delta}D$ values of fluid inclusion water also decrease with decreasing temperature (except for the Daeweon deposit) from -62‰ (substage Ia) to -80‰ (substage Ic and stage III). These trends are interpreted to indicate the progressive cooler, more oxidizing unexchanged meteoric water inundation of an initial hydrothermal system which is composed of highly exchanged meteoric water. Equilibrium thermodynamic interpretation of the mineral assemblages with the variation in amounts of chalcopyrite through the paragenetic time, and the evolution of the Hwacheon-ri hydrothermal fluids indicate that the solubility of copper chloride complexes in the hydrothermal system was mainly controlled by the variation of temperature and $fo_2$ conditions.

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The Study on Risk Factors Analysis and Improvement of VDT Syndrome in Nuclear Medicine (핵의학과 Video Display Terminals Syndrome 유해 요인 조사 및 개선에 관한 연구)

  • Kim, Jung-Soo;Kim, Seung-Jeong;Lee, Hong-Jae;Kim, Jin-Eui;Kim, Hyun-Joo;Han, In-Im;Joo, Yung-Soo
    • The Korean Journal of Nuclear Medicine Technology
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    • v.14 no.1
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    • pp.61-66
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    • 2010
  • Purpose: Recently, Department of Nuclear Medicine have an interest in Video Display Terminals (VDT) syndrome including musculoskeletal disorders, ophthalmologic disorders, trouble of electromagnetic waves and stress disorders occur to VDT workers as the growing number of users and rapid pace of service period supply in large amount. This study research on the actual condition for VDT syndrome in Nuclear Medicine, Seoul National University Hospital (SNUH), discover the problem and draw a plan of upcoming improvement. The aim of this study establish awareness about VDT syndrome and is to prevent for it in the long run. Materials and Methods: Department of Nuclear Medicine, SNUH is composed Principle part, Pediatric part and PET center. We estimated risk factors visit in each part directly. Estimation method use "Check list for VDT work" of Wonjin working environment health laboratory and check list is condition of VDT work, condition of work tables, condition of chairs, condition of keyboards, condition of monitors, working position, character of health management and other working environment. Analysis result is verified in Department of Occupational and Environment, Hallym University Sacred Heard Hospital. Results: As a result of analysis, VDT condition of Department of Nuclear Medicine, SNUH is rule good. In case of work tables, recent of things are suitable to users upon the ergonomical planning, but 15% of existing work tables are below the standard value. In case of chairs are suitable, but 5% of theirs lost optimum capacity become superannuated. The keyboards are suitable for 98% of standard value. In case of monitors, angle control of screen is possible of all, but positioning control is impossible for 38%. In case of working position, 10% is fixed positioning for long time and some of the items researched unsuitable things for standard. At health management point, needed capable of improvement. Also, other working condition as lighting, temperature, noise and ventilation, discovered the problem, but is sufficient to advice value. Conclusion: VDT syndrome is occurrences of possibility continuously, come economical expensive about improvement, is inherent in various causes and originate without your knowledge. So, there is need systematic management system. In Nuclear Medicine, VDT syndrome make it better that constant interest and effort as improvement of ergonomical working environment, improvement of working procedure, regular exercise and steady stretching, and can be prevented fairly. This promote physical and mental condition of worker in top form in comfortable working environment, so this is judged by enlargement of operations efficiency and rising of satisfaction ratings of the inside client.

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The Ratio of Medical Aid over Health Insurance of Age Adjusted Mortality Rate of Tuberculosis and Related Factors (의료보장유형에 따른 연령표준화 결핵 사망률비와 관련 요인)

  • Na, Baeg-Ju;Kang, Moon-Young;Hong, Jee-Young;Kim, Eun-Young;Kim, Keon-Yeop;Lee, Moo-Sik;Yang, Sang Kyu
    • Journal of agricultural medicine and community health
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    • v.31 no.1
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    • pp.9-20
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    • 2006
  • Objectives: This study was aimed at investigating the ratio of medical aid over health insurance of age adjusted mortality rate of tuberculosis and related factors. And we want to compare the ratio of medical aid over health insurance of age adjusted mortality rate of tuberculosis and related factors among the provinces. Methods: In order to compare, the data was referred to National health insurance center for affirming the insurance type of the dead. And age adjusted mortality rate of tuberculosis of each insurance type was analyzed by whole country and the provinces. Related factors of the provinces were gathered from public statistic books. We analysed correlation study between the ratio of medical aid over health insurance of age adjusted mortality rate of tuberculosis and related factors among the provinces. Results: Major findings were as follows 1. The ratio of medical aid over health insurance of age adjusted mortality rate of tuberculosis was 5.6. And the ratio was relatively high at 40-60 ages. 2. The ratio of medical aid over health insurance of age adjusted mortality rate of tuberculosis by the province was varying. And the factors that were financial independence, crowdedness, percent of people on medical aid, population size served by each public health center, number of hospital by a million peoples have correlated with increment of the ratio. Conclusions: As a consequence of tuberculosis control, the ratio was high. Thus this finding suggests that medical utilization and preventive behavior, environment of tuberculosis patient are under handicapped condition. Especially large cities like metropolitan area who have high financial independence, high population density, high percentage of medical aid peoples have high ratio of medical aid over health insurance of age adjusted mortality rate of tuberculosis. There is need for additional and systematic research on the attitude or tendency toward medical services(inc1uding preventive services) utilization of medical aid tuberculosis patients.

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Analysis of a Principal's Cognition on his Job Performance in Meister High Schools (마이스터고등학교 교장의 직무수행에 대한 교장의 인식분석)

  • Hyun, Su;Kim, Jinsoo
    • 대한공업교육학회지
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    • v.38 no.2
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    • pp.27-47
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    • 2013
  • This study aims to suggest a way to improve the professional abilities of the principals of meister high schools by analysing their perception of the standards of performance of their duties. To carry out this study, we have developed the standards of performance of the duties of the principals of meister high schools through the systematic research on the realm of the duties of the principals of meister high schools, and analysed the principals' perception of their duties using the developed standards of performance of their duties. The results of this study are as followed. First, In the stage of planning the school management, the school management plan, the ways to get budget, the plan for evaluation and feedback of the accomplishment of the performance of school management plan should be included. Second, The area of the school management is subdivided into securing school budget, reviewing and arranging the budgets demanded by teachers, executing school budgets, obtaining school equipments and facilities, maintaining school equipments and facilities, managing school feeding, organizing and operating school steering committee, reflecting the opinions of school steering committee. Third, The school curriculum should be developed by a job analysis and the teaching should reflect the analysis. Fourth, The area of the career path and the management of the career for young meisters includes the analysis of the demand of students, parents, and companies, the development of meister growth route and program for managing their career, and the analysis of meister growth route and reflection of the results of the analysis. Fifth, The field of guiding students includes supporting the students counseling service, and managing a variety of school events. 6th, In the realm of cooperation with communities are included designing programs for collaborating and training students with companies, building cooperation with companies, and obtaining supports from communities and related organizations. 7th, In the area of supporting teachers to improve their professional competence, it figured out that supporting teachers' voluntary learning and studying should take a top priority. In conclusion, it is necessary for meister high school principals to have capability to deal with meister growth route and career management, supporting collaboration with other organizations, building and managing laboratories, encouraging teachers' professional improvement, and operating school curriculum and teaching activities.

Relevance of Serum Vitamin D and Indices Related To Cardiovascular Disease Among Korean Adults (한국 성인의 혈청 비타민 D 수준과 심혈관 질환 관련 지표와의 관련성)

  • Kim, Han-Soo;Ryu, So-Yeon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.6
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    • pp.365-374
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    • 2018
  • This study investigated the relationship between Vitamin D levels and indices related to cardiovascular disease in Korean adults aged ${\geq}19years$. The data for analysis were obtained from the sixth Korea National Health Nutrition Examination Survey in 2013 and 2014. The results showed that the incidence of Vitamin D deficiency was 73.1% among Korean adults and that indices related to cardiovascular disease showed an increasing trend (55.6% of Korean adults). The relationship between Vitamin D levels and indices related to cardiovascular disease with controlled physical activity status was also studied. The odds ratios (ORs) for age were 1.72 for the 4-62 years age group (95% CI, 1.53-1.93) and 2.05 for the ${\geq}65years$ age group (95% CI, 1.71-2.45). For blood pressure, the OR for pre-hypertension was 1.30 (95% CI, 1.15-1.47) and that for hypertension was 1.31 (95% CI, 1.11-1.54). For body mass index (BMI), the OR was 1.36 (95% CI, 1.11-1.66) and that for waist circumference (WC) was 1.36 (95% CI, 1.11-1.66). For fasting blood sugar (FBS), the OR for impaired fasting glucose (IFG) was 1.37 (95% CI, 1.21-1.55) and that for diabetes mellitus (DM) was 1.31 (95% CI, 1.05-1.65). The OR for total cholesterol (TC) was 1.30 (95% CI, 1.11-1.52) and that for triglycerides (TG) was 1.20 (95% CI, 1.04-1.37) in Korean adults. There was a significant relationship between Vitamin D and indices related to cardiovascular disease in Korean adults with respect to age, blood pressure, FBS, BMI, TC and TG. Confirmation of a causal relationship between Vitamin D and indices related to cardiovascular disease may require further research consisting of more systematic cohort studies.

Developing and testing the reliability of a measurement tool for an urban area food environment in Korea - Focusing on food stores - (우리나라 도시지역의 식환경 측정을 위한 조사도구 개발 및 신뢰도 검정 - 식품상점을 중심으로 -)

  • Jang, Mi Jin;Shin, Sangah;Kim, Seong-Ah;Chung, Sangwon;Paik, Hee Young;Choe, Jeong-Sook;Hong, Eun Joo;Joung, Hyojee
    • Journal of Nutrition and Health
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    • v.47 no.5
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    • pp.351-363
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    • 2014
  • Purpose: The aim of this study was to develop a reliable measurement tool to assess the urban food environment, particularly focusing on food stores in Korea. Methods: The items for the measurement tool were selected through systematic literature reviews and adjusted to the Korean food environment. A total of 25 food stores in an urban area were recruited for the pilot test to evaluate the time required for completion of the survey, ease of response, willingness to participate, difficulties in conducting the survey, and appropriateness, and 34 food stores were recruited for assessment of the reliability of the tool using percent agreement and kappa value. Results: The measurement tool is composed of questions regarding food store characteristics, accessibility, and food availability. On average, 26 minutes was required to survey a single food store, and the subjects and interviewers answered that the process was not difficult for the survey. The percent agreement for the inter-rater and test-retest reliability ranged from 93.9~98.8% and 91.9~97.9, respectively. The kappa values ranged from 0.78 to 0.97, which was very high. Percent agreement and kappa value of food with healthy option were lower than those of the general food in the inter-rater reliability (p = 0.0027, p = 0.0095 respectively) as well as in the test-retest reliability (p = 0.0081, p = 0.0290, respectively), although they were still high enough (86.4~98.0% for percent agreement, 0.64~0.96 for kappa value). Conclusion: The newly developed measurement tool for assessment of food store environment appears to be feasible and reliable; therefore, it can be applied to research on the association between food environment and dietary behaviors as well as health outcomes.

A Documentational Study on the Development of Chi-Kung-Hak (기공학(氣功學) 발달(發達)에 관한 문헌적(文獻的) 연구(硏究))

  • Kim, Woo Ho;Hong, Won Sik
    • Journal of Korean Medical classics
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    • v.4
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    • pp.19-73
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    • 1990
  • Today, many people are more interested in preventing the disease than curing it. Chi-Kung (氣功) is the way of Life-Cultivation (養生法) peculiar to the orient, it is reported in china that Chi-Kung has an excellent curative value not only in curing the disease but also in preventing it. But the full-scale study of Chi-Kung is not be made up to now in Korea, so I studied the developmental history of chinese Chi-Kung through the oriental medical books. From this study, I reached the following conclusions ; 1. Chi-Kung is naturally derived from the self-preservation instinct to adapt oneself to circumstances of the nature, but in the investigation from the documentational records, it is originated in the treatment method of the Sam-Huang-O-Jae (三皇五帝 )period to cure the abnormal circulation of the vital force and blood caused by damp (濕). 2. As the principle and the method of the Life-Cultivation of the Chun-chu-Jeon-Kook (春秋戰國) periods were recorded in Huang-Jae-Nai-Gyung (黃帝內徑) detailly and the remedy examples by ancient Chi-Kung such as Tao-Yin (導引), Haeng-Chi (行氣) were presented, we considered that theoretical basis of the development of Life-cultivation and Chi-Kung study was furnished in that period. 3. A famous doctor, Hwa-Ta (華陀) lived in Han dynasty, researched the theory and practice of Tao-Yin transmitted from the former generations, as that result, he formed a kind of medical gymnastics what is called O-Keum-Hi (五禽戱). It is considered that 'O-Keum-Hi' is a Tao-Yin method developed more practically and systemetically than the Tao-Yin appeared in the 'Jang-Ja' (莊子) or 'Hoy-Nam-Ja' (淮南子). 4. In Wui-Jin-Nambook Jo (魏晋南北朝) periods, the contents of Chi-Kung were more abundant under the influence of Buddhism (佛敎) and Taoism (道敎). Galhong (葛洪), the author of 'Po-Bak-Ja' (抱朴子) arranged the ancient Chi-Kung method systematically first of all, Tao-Goeng-Gyung (陶宏景), the author of 'Yang-Seong-Yeun-Myung-Rok' (養性延命錄) recorded the 'Yook-Ja-Geul' (六字訣) first time. 5. There is a new development of Chi-Kung therapy in Soo-Tang-Odae (隋唐五代) pefiods, especially So-Won-Bang (巢元方), the author of 'Jey-Byung-Won-Hwu-Ron' (諸病源候論) collected aimost all of the Chi-Kung method, for curing the disease formed before soo (隋) period. From that fact, we supposed that Chi-Kung was utilized more widely in curing the disease. 6. 'So-Ju-Cheon-Hwa-Hu-Peob' (小周天火候法) was adopted as the best orthodox approach under the influence of Nae-Tan-Taoist (道敎內丹學派) in Song-Keum-Won (宋金元) periods, especially in the song dynasty, 'Pal-Dan-Geum' (八段錦) was appeared and assignment of six-Chi (六氣) for bowel and viscera in the 'Yook-Ja-Geul' (六字訣) was decided firmly, that is to say Lung-Si (肺-呬), Heart-Kha (心-呵), Spleen-Hoa (脾-呼), Liver-Hoe (肝-噓), Kidneychui (賢-吹), Three-Burner-shi (三焦-嘻). 7. In Myung-Cheong (明淸) periods, The general practitioner applied the principle of 'Byun-Jeng-Ron-Chi' (辨證論治) to the Chi-Kung field, and after Myeong dynasty the style of doing 'Yook-Ja-Gyel' (六字訣) was developed to the moving style. 8. Today, in china, the study on the Chi-Kung is being progressed constantly under the positive assistance of government, Chi-Kung-Hak (氣功學) has taking its place as a branch of study step by step. It is considered that the establishment of Chi-Kung-Hak Classroom (氣功學教室) and Medical Chi-Kung Center (氣功療法室) for special and systematic research are needed, at the same time the settlement of institutional system for training the Chi-Kung technician (氣功師) is also needed.

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Classification System of Wetland Ecosystem and Its Application (습지생태계 분류체계의 검토 및 적용방안 연구)

  • Chun, Seung Hoon;Lee, Byung Hee;Lee, Sang Don;Lee, Yong Tae
    • Journal of Wetlands Research
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    • v.6 no.3
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    • pp.55-70
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    • 2004
  • The wetland ecosystem is a complex products of various erosion force, accumulation as water flows, hydrogeomorphic units, seasonal changes, the amount of rainfalls, and other essential element. There is no single, correct, ecologically sound definition for wetlands because of the diversity of wetlands and the demarcation between dry and wet environments occurs along a continuum, but wetland plays various ecosystem functions. Despite comprehensive integration through classification and impact factors there is still lacking in systematic management of wetlands. Classification system developed by the USFWS(1979) is hierarchical progresses from systems and subsystems at general levels to classes, subclasses, dominance types, and habitat modifiers. Systems and subsystems are delineated according to major physical attributes such as tidal flushing, ocean-derived salts, and the energy of flowing water or waves. Classes and subclasses describe the type of substrate and habitat or the physiognomy of the vegetation or faunal assemblage. Wetland classes are divided into physical types and biotic types. For the wise management of wetlands in Korea, this study was carried out to examine methodology of USFWS classification system and discuss its application for Korean wetland hydrogeomorphic units already known. Seven wetland types were chosen as study sites in Korea divided into some different types based on USFWS system. Three wetland types belonging to palustrine system showed no difference between Wangdungjae wetland and Mujechi wetland, but Youngnup of Mt. Daeam was different from the former two types at the level of dominant types. This fact means that setting of classification system for management of wetland is needed. Although we may never know much about the wetland resources that have been lost, there are opportunities to conserve the riches that remain. Extensive inventory of all wetland types and documentation of their ecosystem functions are vital. Unique and vulnerable examples in particular need to be identified and protected. Furthermore, a framework with which to demonstrate wetland characteristics and relationships is needed that is sufficiently detailed to achieve the identification of the integrity and salient features of an enormous range of wetland types.

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Psychosocial Characteristics and Factors Associated with Referral to Psychiatric Care in the Suicide Attempters Visiting Emergency Center (응급실에 내원한 자살 시도자들의 정신사회학적 특성과 정신건강의학과 진료 의뢰 관련 요인)

  • Kwon, Jung-Woo;Ko, Young-Hoon;Han, Chang-Su;Lee, Moon-Soo;Yoon, Ho-Kyung;Lee, Hongjae
    • Korean Journal of Psychosomatic Medicine
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    • v.21 no.2
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    • pp.106-113
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    • 2013
  • Objectives: The purpose of this study was to examine the characteristics and the psychosocial factors associated to the referral to psychiatric care in the suicide attempters visiting emergency center. Methods: We conducted a systematic chart review of 377 suicidal attempters visiting emergency center of the Korea University Ansan Hospital between January 2008 and December 2011. We gathered a data contain 20 items including psychosocial characteristics and factors related to suicide and factors related to psychiatric treatment. Multivariate logistic regression models were fitted to data to estimate the unique effects of sex, drunken status, companion, suicidal methods, place of suicide and current use of psychiatric medication on the referral to psychiatric care. Results: The female gender(OR=1.63, 95% CI=0.99-2.69), suicidal attempts at home(OR=3.40, 95% I= 1.21-9.56) and drunken state at visit(OR=2.34, 95% CI=1.10-5.01) are the factors that predict the risk of the non-referral of the patients to psychiatric intervention. Place of suicidal attempt was the most important factor do play a role in determining whether referral to psychiatric care will take place or not. Current use of psychiatric medication showed a trend toward significance(p=0.08, OR=1.67, 95% CI=0.95-2.95). Conclusions: These results suggest that when deciding whether to adapt or to refuse the referral to psychiatric care, the factors such as suicidal intent, lethality of suicide methods, familiar factors and alcohol may contribute onto the referral to psychiatric care. Additional research is required to investigate an association of these factors with referral to psychiatric care.

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