• 한국전산구조공학회논문집
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• 제27권1호
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• pp.9-16
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• 2014

레벨셋 기법과 위상민감도를 이용하여 선형 탄성 구조물에 대하여, 초기 설계형상에 의존성이 없는 위상 및 형상 최적설계 기법을 개발하였다. 레벨셋 기법에서는 복잡한 위상 형상변화를 쉽게 다루기 위해 초기 영역은 고정한 채 레벨셋 함수로 표현되는 암시적 이동경계로 경계를 표현한다. 해밀턴-자코비(H-J) 방정식과 수치적으로 강건한 기법인 'up-wind scheme'은 컴플라이언스 목적함수를 최소화시키고 허용체적 제약조건을 만족시키면서, 초기 암시적 경계를 법선 속도장에 따라 최적의 형상으로 이끌어 낸다. 점근적인 정규화 개념에 근거하여, 구멍의 반지름을 0으로 접근시켜 형상 미분의 극한을 취한 위상민감도를 고려하였다. 최적조건으로부터 유도된 라그란지안의 감소 방향을 이용하여 H-J 방정식을 갱신하기 위한 속도장을 결정하였다. 개발한 방법에서는 위상민감도로부터 얻어지는 지표를 이용하여 구멍을 언제든지 어디에서나 생성가능하기 때문에 초기 구멍이 최적 형상을 얻기 위해 요구되지 않는다는 사실을 확인하였다. 또한 효율적인 최적화 과정을 위해서는 구멍 생성을 위한 조정변수의 적절한 선택이 중요함을 확인하였다.

• 생명과학회지
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• 제31권9호
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• pp.796-805
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• 2021

간 소포체(ER) 스트레스는 비알콜성지방간과 인슐린 저항성의 발달에 기여하고, unfolded protein response(UPR)의 구성요소는 지질 대사를 조절한다. 최근 연구에 따르면 ER 스트레스와 비정상적인 세포 지질 대사 사이의 연관성이 보고되었으며, 이 과정에서 지질 대사의 중심 조절자인 sterol regulatory element binding proteins(SREBPs)의 관련성이 확인되었다. 그러나 ER 스트레스 동안 지질 대사를 조절하는 SREBP의 정확한 역할과 비알콜성지방간에 대한 기여는 아직 밝혀지지 않았다. 본 연구에서 SREBP-1c 결핍은 UPR, 염증 및 지방산 산화 조절을 통해 ER 스트레스에 의해 유도된 비알콜성지방간으로부터 생쥐를 보호한다는 것을 보여준다. SREBP-1c는 inositol requiring kinase 1α (IRE1α) 발현을 직접적으로 조절하고 ER 스트레스에 의해 유도된 tumor necrosis factor-α의 활성화를 매개하여 peroxisome proliferator-activated receptor γ coactivator 1-α (PGC1α)의 감소와 그에 따른 지방산 산화의 장애를 유발한다. 그러나, SREBP-1c의 유전적 결핍은 이러한 현상을 보호하여 간 염증과 지방 축적을 완화시킨다. SREBP-1c 결핍이 ER 스트레스에 의해 유도된 염증 신호를 방지하는 메커니즘은 아직 밝혀지지 않았지만, SREBP-1c가 결핍된 Kupffer 세포에서 IRE1α 신호의 변화가 염증 신호에 관여할 수 있을 것으로 생각된다. 본 연구결과는 SREBP-1c가 ER 스트레스에 의해 유도된 비알콜성지방간에서 UPR 및 염증의 조절에 중요한 역할을 함을 시사한다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권9호
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• pp.3639-3644
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• 2015

Oral, cervical and breast cancers, which are either preventable and/or amenable to early detection and treatment, are the leading causes of cancer-related morbidity and mortality in India. In this paper, we describe implementation science research priorities to catalyze the prevention and control of these cancers in India. Research priorities were organized using a framework based on the implementation science literature and the World Health Organization's definition of health systems. They addressed both community-level as well as health systems-level issues. Community-level or "pull" priorities included the need to identify effective strategies to raise public awareness and understanding of cancer prevention, monitor knowledge levels, and address fear and stigma. Health systems-level or "push" and "infrastructure" priorities included dissemination of evidence-based practices, testing of point-of-care technologies for screening and diagnosis, identification of appropriate service delivery and financing models, and assessment of strategies to enhance the health workforce. Given the extent of available evidence, it is critical that cancer prevention and treatment efforts in India are accelerated. Implementation science research can generate critical insights and evidence to inform this acceleration.

• 천문학회보
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• 제39권1호
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• pp.68.1-68.1
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• 2014

We present the results of far-ultraviolet (FUV) observations of comet C/2001 Q4 (NEAT) obtained with Far-ultraviolet Imaging Spectrograph (FIMS) on board the Korean microsatellite STSAT-1, which operated at an altitude of 700 km in a sun-synchronous orbit. FIMS is a dual channel imaging spectrograph (S-channel 900-1150 ${\AA}$, L-channel 1350-1710 ${\AA}$, and ${\lambda}/{\Delta}{\lambda}$ ~ 550 for both channels) with large image fields of view (S-channel $4.0^{\circ}{\times}4.6^{\prime}$, L-channel $7.5^{\circ}{\times}4.3^{\prime}$, and angular resolution ~ $5-10^{\prime}$) optimized for the observation of diffuse emission of astrophysical radiation. Comet C/2001 Q4 (NEAT) were made in two campaigns during its perihelion approach between May 8 and 15, 2004. Based on the scanning mode observations in the wavelength band of 1400-1700 ${\AA}$, we have constructed an image of the comet with an angular size of $5^{\circ}{\times}5^{\circ}$, which corresponds to the central coma region. Several important fluorescence emission lines were detected including S I multiplets at 1429 and 1479 ${\AA}$, C I multiplets at 1561 and 1657 ${\AA}$, and the CO $A^1{\Pi}-X^1{\Sigma}^+$ Fourth Positive system; we have estimated the production rates of the corresponding species from the fluxes of these emission lines. The estimated production rate of CO was $Q_{CO}=(2.65{\pm}0.63){\times}10^{28}s^{-1}$, which is 6.2-7.4% of the water production rate and is consistent with earlier predictions. The average carbon production rate was estimated to be $Q_C={\sim}1.59{\times}10^{28}s^{-1}$, which is ~60% of the CO production rate. However, the observed carbon profile was steeper than that predicted using the two-component Haser model in the inner coma region, while it was consistent with the model in the outer region. The average sulfur production rate was $Q_S=(4.03{\pm}1.03){\times}10^{27}s^{-1}$, which corresponds to ~1% of the water production rate.

• Journal of Astronomy and Space Sciences
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• 제31권1호
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• pp.15-23
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• 2014

We present preliminary observations of the field-aligned-irregularities (FAIs) in the E and F regions during the solar minimum (2009 - 2010) using the 40.8 MHz coherent backscatter radar at Daejeon ($36.18^{\circ}N$, $127.14^{\circ}E$, $26.7^{\circ}N$ dip latitude) in South Korea. The radar, which consists of 24 Yagi antennas, observes the FAIs using a single beam with a peak power of 24 kW. The radar has been continuously operated since December 2009. Depending on the manner of occurrence of the backscatter echoes, the E-region echoes are largely divided into two types: quasi-periodic (QP) and continuous echoes. Our observations show that the QP echoes occur frequently above an altitude of 105 km in the post-sunset period and continuous echoes occur preferentially around an altitude of 105 km in the post-sunrise period. QP echoes appear as striated discrete echoes for a period of about 10 - 20 min. The QP-type echoes occur more frequently than the continuous-type echoes do and the echo intensity of the QP type is stronger than that of the continuous type. In the F region, the FAIs occur at night at an altitude interval of 250 - 450 km. As time proceeds, the occurrence height of the FAIs gradually increases until early in the morning and then decreases. The duration of the F-region FAIs is typically a few hours at night, although, in rare cases, FAIs persist throughout the night or appear even after sunrise. We discuss the similarities and differences of the FAIs observed by the Daejeon radar in comparison with other radar observations.

• Asian Pacific Journal of Cancer Prevention
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• 제14권12호
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• pp.7725-7730
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• 2013

Objective: The purpose of this study was to evaluate secondhand smoke (SHS) exposure inside selected public places to provide basic data for the development and promotion of smoke-free policies. Methods: Between March and May 2009, an SHS exposure survey was conducted. $PM_{2.5}$ levels and air nicotine concentrations were measured in hospitals (n=5), government buildings (4), restaurants (10) and entertainment venues (10) in Seoul, Republic of Korea, using a common protocol. Field researchers completed an observational questionnaire to document evidence of active smoking (the smell of cigarette smoke, presence of cigarette butts and witnessing people smoking) and administered a questionnaire regarding building characteristics and smoking policy. Results: Indoor $PM_{2.5}$ levels and air nicotine concentrations were relatively higher in monitoring sites where smoking is not prohibited by law. Entertainment venues had the highest values of $PM_{2.5}$(${\mu}g/m^3$) and air nicotine concentration(${\mu}g/m^3$), which were 7.6 and 67.9 fold higher than those of hospitals, respectively, where the values were the lowest. When evidence of active smoking was present, the mean $PM_{2.5}$ level was 104.9 ${\mu}g/m^3$, i.e., more than 4-fold the level determined by the World Health Organization for 24-hr exposure (25 ${\mu}g/m^3$). Mean indoor air nicotine concentration at monitoring sites with evidence of active smoking was 59-fold higher than at sites without this evidence (2.94 ${\mu}g/m^3$ vs. 0.05 ${\mu}g/m^3$). The results were similar at all specific monitoring sites except restaurants, where mean indoor $PM_{2.5}$ levels did not differ at sites with and without active smoking evidence and indoor air nicotine concentrations were higher in sites without evidence of smoking. Conclusion: Nicotine was detected in most of our monitoring sites, including those where smoking is prohibited by law, such as hospitals, demonstrating that enforcement and compliance with current smoke-free policies in Korea is not adequate to protect against SHS exposure.

• 한국간호교육학회지
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• 제4권1호
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• pp.66-80
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• 1998

With the opening of healthcare market, the health care environment in Korea is anticipating a drastic change. In this Internationally open market environment, it is necessary to introduce a systematic health care plan and DRG system which offer qualitative medical services as well as reduced cost. Purpose of this study is to develop and test the critical pathway for Cesarean section patient in the way to be possible the integrated inpatient management. It was adopted the process of six phases to develop the critical pathway as the theoretical framework implemented by Johns Hopkins Hospital, Maryland, U.S.A. In the first phase, make a selection of diagnosis/procedures to develop. In the second phase, organize a development team consisted of eight expertises working in maternity nursing area. In the third phase, analyze the overall medical service offered to patient through review medical records and decided the service content and the implementation period for the Cesarean section patient. In the forth phase, make out a preliminary critical pathway after verification of expert group on content validity. In the fifth phase, validity operate to ten Cesarean section patients to test implementation in practice by using the preliminary critical pathway, In the sixth phase, defined the final critical pathway. The result of this study was as follows. 1. There were classified 8 categories as monitoring/assesment, treatment, medication, activity, diet, test, consult, education/discharge plan for vertical axis and showed hospital stayed from admission to discharge for horizontal axis of critical pathway through analysis 68 Cesarean section patients medical records. 2. After critical review 68 medical records to make out a preliminary critical pathway, hospital stays for horizontal axis were showed 6 days, mean hospital stays were 7.5 days, 2.1 days were to be taken operation after admission and 4.2 days were stayed until discharge after operation. 3. After making out a questionare in 90 items of a medical service content of eight categories and verifying the content validity of expertises, the 85 items of the preliminary critical pathway were selected by expertises agreement over 88% and modified or deleted 5 items showing agreement below 75%. 4. After verifying a validity to 10 patients for 4 weeks, hospital stays were 5.9 days. There were deleted 1 item and modified or supplemented the 9 items of the 10 items.

• 한국응용과학기술학회지
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• 제25권4호
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• pp.539-555
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• 2008

It is well understood that developing new drugs is one of the highest value-added businesses in a country; however, the current governments' spending in pharmaceutical research and development(R&D) is minimal in Korea. This paper suggests that different governmental bodies should take in charge of different stages of the R&D process in order to maximize the use of limited government research funding. First, during the initial phase of the drug development, including clinical trials, the Ministry of Education, Science and Technology is the most appropriate governmental organization to support the research. For later procedures such as supporting the industries for exporting developed drugs, legislative approvals, and building infrastructure for future clinical trials should be supported by the Ministry of Knowledge and Economy and the Ministry of Health and Welfare along with the Korea Food and Drug Administration(KFDA). The KFDA, which is the main governmental agency approving newly developed drugs in the market, will need to take a crucial responsibility in the initial phase of the pharmaceutical R&D by guiding the industries with timely and proper information. As a first step, it is recommended to set up and operate a center for supporting new drugs, so that the industries can facilitate the development of marketable drugs which meet customers' needs. Later, in order to expedite the process of exporting and getting approvals of the newly developed drugs from foreign countries, it is necessary to develop new approval system, which includes introduction of the Good Manufacturing Practice (GMP), mandatory validation system, and education program for supporting expertise. Lastly, the KFDA needs to take an active role in developing Korean pharmaceutical industries by communicating with other foreign governments with regards to the globalization of the Korean pharmaceutical industries. For example, as a follow up after the Free Trade Agreement(FTA), active discussion on GLP of Mutual Recognition Agreement(MRA) with the United States of America, should be seriously considered.

• Asian Pacific Journal of Cancer Prevention
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• 제15권20호
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• pp.8607-8612
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• 2014

Background: Breast cancer patients experience a variety of altered appearance - such as loss or disfigurement of breasts, discolored skin, and hair loss - which result in psychological distress that affect their quality of life. This study aims to evaluate the impact of socioeconomic status on the altered appearance distress, body image, and quality of life among Korean breast cancer patients. Materials and Methods: A cross-sectional survey was conducted at advocacy events held at 16 different hospitals in Korea. Subjects were eligible to participate if they were 18 years of age or older, had a histologically confirmed diagnosis of breast cancer, had no evidence of recurrence or metastasis, and had no psychological problems at the time of the survey. Employment status, marital status, education, and income were assessed for patient socioeconomic status. Altered appearance distress was measured using the NCI's cancer treatment side effects scale; body image and quality of life were measured by the EORTC QLC-C30 and BR23. Means and standard deviations of each outcome were compared by socioeconomic status and multivariate linear regression models for evaluating the association between socioeconomic status and altered appearance distress, body image, and quality of life. Results: A total of 126 breast cancer patients participated in the study; the mean age of participants was 47.7 (SD=8.4). Of the total, 83.2% were married, 85.6% received more than high school education, 35.2% were employed, and 41% had more than $3000 in monthly household income. About 46% had mastectomy, and over 30% were receiving either chemotherapy or radiation therapy at the time of the survey. With fully adjusted models, the employed patients had significantly higher altered appearance distress (1.80 vs 1.48; p<0.05) and poorer body image (36.63 vs 51.69; p<0.05) compared to the patients who were unemployed. Higher education (10.58, standard error (SE)=7.63) and family income (12.88, SE=5.08) was positively associated with better body image after adjusting for age, disease stage at diagnosis, current treatment status, and breast surgery type. Similarly, patients who were married and who had higher education had better quality of life were statistically significant in the multivariate models. Conclusions: Socioeconomic status is significantly associated with altered appearance distress, body image, and quality of life in Korean women with breast cancer. Patients who suffer from altered appearance distress or lower body image are much more likely to experience psychosocial, physical, and functional problems than women who do not, therefore health care providers should be aware of the changes and distresses that these breast cancer patients go through and provide specific information and psychosocial support to socioeconomically more vulnerable patients.

• Journal of Preventive Medicine and Public Health
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• 제30권1호
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• pp.45-59
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• 1997

소아에서부터 청소년기까지 혈청 지질의 지속성(tracking)은 서구에서 행해진 연구들에 의해서 이미 잘 알려져 있으나 국내에서는 이에 관한 연구가 거의 이루어지지 않았다. 본 연구는 우리나라 청소년의 혈청 지질치의 변화를 조사하고 지속성이 있는지를 분석하였다. 연구대상은 경기도 강화군에서 진행하고 있는 강화 아동 혈압 코호트(719명)의 청소년들로 12세, 14세, 16세 세 번에 걸쳐서 공복 후 혈액검사(혈청 총 콜레스테롤, 중성지방, LDL 콜레스테롤, HDL 콜레스테롤을 포함)와 신체계측을 시행하였다. 이 중 3번의 혈액 검사에서 10시간 이상의 공복이 확인된 청소년 309명 (남자 162명, 여자 147명)을 최종 연구대상으로 선정하였다. 연구대상이 된 청소년들과 연구대상에서 제외한 청소년들의 12세때 초기 검사치들을 t 검정을 이용하여 서로 비교한 결과 통계학적으로 유의한 차이는 없었다. 연구방법은 우선 혈청 지질치의 변화양상을 보기 위하여 각 검사 년도간에 반복 측정된 분산분석을 시행하였다. 각 혈청지질의 지속성을 보기 위해서는 첫께, 초기값을 바탕으로 사분위 집단으로 나누어 각 사분위 집단의 혈청지질치가 매 검사 연도마다 어떻게 변하는 지를 그림으로 나타내었다. 둘째, 혈청지질치의 검사 시기사이의 스피어맨 상관계수를 구하였다. 그리고 마지막으로 각 검사 년도의 혈청지질치를 사분위 집단으로 구분하여 초기검사에서 가장 위험도가 큰 집단에 속한 사람들이 지속적으로 위험도가 큰 집단에 속하는 백분율을 계산하였다. 연구결과 남녀 모두 4년간 세 번의 검사에서 혈청 총 콜레스테롤은 남자가 초기검사에서 $160.7{\pm}25.3mg/dl$, 최종 추적검사에서 $150.0{\pm}27.8mg/dl$, 여자가 초기검사에서 $168.8{\pm}29.7mg/dl$, 최종 추적검사에서 $168.8{\pm}29.7mg/dl$, 중성지방은 남자가 $98.0{\pm}45.7mg/dl$에서, $114.1{\pm}67.9/mg/dl$로, 여자가 $109.9\geq37.1mg/dl$에서, $104.9{\pm}47.6mg/dl$로, LDL 콜레스테롤은 남자가 $93.6{\pm}21.2mg/dl$에서, $83.0{\pm}25.0mg/dl$로 여자가 $83.0{\pm}25.0mg/dl$에서, $94.7{\pm}24.4mg/dl$로, HDL 콜레스테롤은 남자가 $47.6{\pm}9.1mg/dl$에서, $44.2{\pm}9.4mg/dl$로, 여자가 $48.8{\pm}10.0mg/dl$에서, $47.8{\pm}11.3mg/dl$ 변화하였다. 반복 측정한 분산분석 결과 남녀 모두 4년 동안 혈청 총 콜레스테롤, LDL 콜레스테롤, HDL콜레스테롤이 통계적으로 유의하게 감소하였다. 특히 남자 LDL 콜레스테롤은 두 번의 추적검사에서 모두 감소한 것으로 나타났다. 중성지방은 남자에서는 지속적으로 증가하였고 여자에서는 변화가 없었다. 같은 연령에서 남녀간의 각 혈청지질치를 비교해보면 중성지방을 제외하고는 모두 여자가 남자보다 더 컸다. 혈청 지질의 초기 검사와 최종 검사간의 스피어맨 상관분석과 각 혈청 지질치의 위험도가 가장 큰 사분위집단에 잔류하는 백분율을 보면 지속성이 존재하였다. 혈청 총 콜레스테롤과 HDL 콜레스테롤에서 각 시기의 검사치들의 상관계수는 남자가 0.6 이상, 여자가 약 0.7 이상이었으며 통계적으로 유의하였다. 첫 번께 검사에서 위험도가 가장 큰 사분위 집단에 속한 사람 중 두 번째 검사에서도 위험도가 가장 큰 사분위 집단에 속한 백분율은 여자의 중성지방(42.9%)을 제외하고는 모두 50%이상이었다. 이들이 세 번째 검사에서도 같은 사분위 집단에 잔류한 백분율은 여자의 중성지방(25.7%)을 제외하고 모두 35%이상이었다. 결론적으로 청소년기의 혈청 지질치는 지속성이 있음을 알 수 있었다. 그러나 본 연구는 4년 동안의 변화이고 성인까지의 변화를 보기 위해서는 좀 더 장기적인 연구가 필요하다.