• Journal of Preventive Medicine and Public Health
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• 제34권3호
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• pp.262-268
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• 2001

Objectives : To integrate the results of studies which assess an association between blood lead and blood pressure. Methods : We surveyed the existing literature using a MEDLINE search with blood lead and blood pressure as key words, including reports published from January 1980 to December 2000. The criteria for quality evaluation were as follows: 1) the study subjects must have been workers exposed to lead, and 2) both blood pressure and blood lead must have been measured and presented with sufficient details so as to estimate or calculate the size of the association as a continuous variable. Among the 129 articles retrieved, 13 studies were selected for quantitative meta-analysis. Before the integration of each regression coefficient for the association between blood pressure and blood lead, a homogeneity test was conducted. Results : As the homogeneity of studies was rejected in a fixed effect model, we used the results in a random effect model. Our quantitative meta-analysis yielded weighted regression coefficients of blood lead associated with systolic blood pressure and diastolic blood pressure results of 0.0047 (95% confidence interval [CI]: -0.0061, 0.0155) and 0.0004 (95% CI: -0.0031, 0.0039), respectively. Conclusions : The published evidence suggested that there may be a weak positive association between blood lead and blood pressure, but the association is not significant.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.4102-4102
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• 2001

In multivariate analysis, absorbance spectrum is measured over a band of wavelengths. One does not often pay attention to the size of this wavelength band. However, it is desirable that spectrum is measured at only necessary wavelengths as long as the acceptable accuracy of prediction can be met. In this paper, the method of selecting an optimal band of wavelengths based on the loading vector analysis was proposed and applied for determining total protein in human serum using near-infrared transmission spectroscopy and PLSR. Loading vectors in the full spectrum PLSR were used as reference in selecting wavelengths, but only the first loading vector was used since it explains the spectrum best. Absorbance spectra of sera from 97 outpatients were measured at 1530∼1850 nm with an interval of 2 nm. Total protein concentrations of sera were ranged from 5.1 to 7.7 g/㎗. Spectra were measured by Cary 5E spectrophotometer (Varian, Australia). Serum in the 5 mm-pathlength cuvette was put in the sample beam and air in the reference beam. Full spectrum PLSR was applied to determine total protein from sera. Next, the wavelength region of 1672∼1754 nm was selected based on the first loading vector analysis. Standard Error of Cross Validation (SECV) of full spectrum (1530∼l850 nm) PLSR and selected wavelength PLSR (1672∼1754 nm) was respectively 0.28 and 0.27 g/㎗. The prediction accuracy between the two bands was equal. Wavelength selection based on loading vector in PLSR seemed to be simple and robust in comparison to other methods based on correlation plot, regression vector and genetic algorithm. As a reference of wavelength selection for PLSR, the loading vector has the advantage over the correlation plot since the former is based on multivariate model whereas the latter, on univariate model. Wavelength selection by the first loading vector analysis requires shorter computation time than that by genetic algorithm and needs not smoothing.

• 한국습지학회지
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• 제18권2호
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• pp.148-153
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• 2016

하도 홍수추적과 관련하여 하천에서의 시 공간적 홍수파를 해석하는데 수리학적 방법과 수문학적 방법이 일반적으로 많이 이용되어 왔다. 수문학적 홍수추적 방법은 수리학적 방법에 비해 수행하기에는 비교적 간단하면서도 합리적인 정확성을 지닌다. 수문학적 홍수추적 방법 중 광범위하게 적용되어지고 있는 Muskingum 모형의 중요 변수인 저류상수는 유하시간과 매우 유사한 값을 가진다. 이러한 점에 착안하여 본 연구에서는 저류상수를 산정하기 위해 HEC-RAS를 이용한 유하시간을 산정하고, 하도거리, 하도경사, 유량 자료를 이용하여 유하시간에 대한 비선형 회귀곡선식을 개발하였다. 비선형 회귀곡선에 의해서 산정된 저류상수를 Muskingum 모형에 대입하여 구한 유출량은 HEC-RAS 1차원 부정류 모의를 적용하여 산정된 유출량과 비교하였다. 이와 함께 본 연구에서는 가중인자에 대한 영향 및 상하류 사이의 구간 분할에 대해서 검토하였는데, 그 결과 가중인자 값이 클수록 첨두홍수량이 올라가는 것으로 나타났으며, 구간 분할을 많이 할수록 RMSE가 감소하는 것으로 나타났다.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제20권1호
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• pp.22-26
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• 2017

Purpose: The diagnosis of cow's milk (CM) allergy is a challenge. The Cow's Milk-related-Symptom-Score ($CoMiSS^{TM}$) was developed to offer primary health care providers a reliable diagnostic tool for CM related symptoms. The predictive prospective value of the $CoMiSS^{TM}$ was evaluated in three clinical trials. Methods: Pooled analyses of the three studies were conducted based on regressing the results of the month-1 challenge test on the month-1 $CoMiSS^{TM}$, adjusting for baseline $CoMiSS^{TM}$ using a logistic regression model. In addition a logistic regression model was also fitted to the month-1 challenge test result with the change in $CoMiSS^{TM}$ from baseline as a predictor. Results: Results suggest that infants having a low $CoMiSS^{TM}$ (median, 5) after 1 month dietary treatment free from intact CM protein have a significant risk of having a positive challenge test (odds ratio, 0.83; 95% confidence interval, 0.75-0.93; p=0.002). Pooled data suggest that the change in $CoMiSS^{TM}$ from baseline to month-1 can predict CM related symptoms as a confirmed diagnosis according to the challenge test at month-1. However, in order to validate such a tool, infants without CM related symptoms would also need to be enrolled in a validation trial. A concern is that it may not be ethical to expose healthy infants to a therapeutic formula and a challenge test. Conclusion: Pooled data analysis emphasizes that the $CoMiSS^{TM}$ has the potential to be of interest in infants suspected to have CM-related-symptoms. A prospective validation trial is needed.

• 대한간호학회지
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• 제52권5호
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• pp.511-521
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• 2022

Purpose: This study aimed to examine the moderating effect of organizational justice on the relationship between self-efficacy and nursing performance among clinical nurses. Methods: In January 2021, a cross-sectional survey was conducted with 224 clinical nurses recruited from a university-affiliated hospital in Suwon, South Korea. Participants completed online-based, self-report structured questionnaires. Collected data were analyzed using multiple regression and a simple model of PROCESS macro with a 95% bias-corrected bootstrap confidence interval. Results: Self-efficacy and organizational justice were found to be significant predictors of nursing performance. These two predictors explained the additional 34.8% variance of nursing performance in the hierarchical regression model, after adjusting the other covariates. In addition, organizational justice moderated the relationship between self-efficacy and nursing performance among the clinical nurses. In particular, at low self-efficacy level, participants with high organizational justice had higher nursing performance compared to those with low organizational justice. Conclusion: Enhancing organizational justice can be used as an organizational strategy for improving the organizational culture in terms of distribution, procedure, and interaction. Ultimately, these efforts will contribute to the improvement of nursing performance through a synergistic effect on organizational justice beyond nurses' individual competency and self-efficacy.

• Journal of Korean Biological Nursing Science
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• 제25권3호
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• pp.160-171
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• 2023

Purpose: To identify factors influencing health-related quality of life for young single-person households, this study investigated physical and mental health status, health behavior, depression, resilience, and health-related quality of life. Methods: An online survey was administered to members of young single-person households from March 22 to 30, 2022. The data were analyzed using the chi-square test, independent t-test, one-way analysis of variance, Pearson correlation coefficients, multiple regression, and a simple mediation model applying the PROCESS macro model 4 with 95% bias-corrected bootstrapped confidence intervals. Results: The participants were 229 members of young single-person households. Health-related quality of life showed significant relationships with residence (t = 2.80, p = .006), month (F = 3.70, p = .026), mental health status (F = 20.33, p < . 001), and high-intensity exercise (F = 7.35, p = .001) among general and health-related characteristics. Health-related quality of life had significant correlations with depression (r = -.72, p < .001) and resilience (r = .58, p < .001). Multiple regression analysis showed that depression (β = -.57, p < .001) and resilience (β = .21, p < .001) influenced health-related quality of life. Moreover, resilience had a mediating effect between depression and health-related quality of life (indirect effect = -0.002, 95% bias-corrected bootstrapped confidence interval = -0.003 to -0.001). Conclusion: Members of young single-person households tended to be more vulnerable to emergency situations, such as during the coronavirus disease 2019 pandemic, when lockdowns and quarantines were frequent. To improve health-related quality of life in young single-person households, people with high levels of depression or low levels of resilience need special attention and support to promote mental health.

• Journal of Periodontal and Implant Science
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• 제53권4호
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• pp.283-294
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• 2023

Purpose: The aim of this study was to investigate the relationship between serum uric acid (SUA) levels and the risk of periodontitis in Korean adults using data from the Korean National Health and Nutrition Examination Survey (KNHANES). Methods: This cross-sectional study used data from the KNHANES 2016-2018 and analysed 12,735 Korean adults aged ≥19 years who underwent oral examinations. Hypouricemia was defined as SUA <3 mg/dL in men and <2 mg/dL in women, and hyperuricemia was defined as SUA ≥7 mg/dL in men and ≥6 mg/dL in women. Results: The weighted prevalence of hypouricemia and hyperuricemia was 0.6% and 12.9%, respectively. The overall weighted periodontitis rate was 30.5%. The frequency of periodontitis in subjects with hypouricemia, normouricemia, and hyperuricemia were 51.1%, 30.3%, and 30.6%, respectively. Study participants with hypouricemia were significantly older, had significantly fasting blood glucose levels, and had better kidney function than non-hypouricemic participants. In univariate logistic regression analyses, hypouricemia was associated with periodontitis, but hyperuricemia was not. The fully adjusted model revealed that the adjusted odds ratio of hypouricemia for periodontitis was 1.62 (95% confidence interval, 1.13-2.33), while the relationship between hyperuricemia and periodontitis in the multivariable logistic regression model was not significant. Conclusions: The results of this study suggest that hypouricemia is associated with an increased risk of periodontitis.

• Journal of Preventive Medicine and Public Health
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• 제55권3호
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• pp.297-306
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• 2022

Objectives: The incidence of cardiovascular disease (CVD) mortality is increasing in developing countries. This study aimed to decompose the socioeconomic inequality of CVD in Iran. Methods: This cross-sectional population-based study was conducted on 20 519 adults who enrolled in the Ardabil Non-Communicable Disease cohort study. Principal component analysis and multivariable logistic regression were used, respectively, to estimate socioeconomic status and to describe the relationships between CVD prevalence and the explanatory variables. The relative concentration index, concentration curve, and Blinder-Oaxaca decomposition model were used to measure and decompose the socioeconomic inequality. Results: The overall age-adjusted prevalence of CVD was 8.4% in northwest Iran. Multivariable logistic regression showed that older adults, overweight or obese adults, and people with hypertension and diabetes were more likely to have CVD. Moreover, people with low economic status were 38% more likely to have CVD than people with high economic status. The prevalence of CVD was mainly concentrated among the poor (concentration index, -0.077: 95% confidence interval, -0.103 to -0.060), and 78.66% of the gap between the poorest and richest groups was attributed to differences in the distribution of the explanatory variables included in the model. Conclusions: The most important factors affecting inequality in CVD were old age, chronic illness (hypertension and diabetes), marital status, and socioeconomic status. This study documented stark inequality in the prevalence of CVD, wherein the poor were more affected than the rich. Therefore, it is necessary to implement policies to monitor, screen, and control CVD in poor people living in northwest Iran.

• Journal of Korean Biological Nursing Science
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• 제26권3호
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• pp.228-239
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• 2024

Purpose: This retrospective study was conducted to identify factors associated with repeated suicide attempts by analyzing the electronic medical records of suicide attempters who visited emergency medical centers due to drug intoxication. Methods: Data from January 1, 2020 to December 31, 2021 were collected for this study and analyzed using SPSS/WIN 25.0. Results: In this study, the factors affecting repeated suicide attempts among individuals who visited the emergency medical center due to acute drug intoxication were the presence or absence of psychiatric diseases, the season of drug intoxication, and age. In order to identify the factors affecting repeated suicide attempts in those who presented with acute drug intoxication, logistic regression analysis was performed by inputting psychiatric diseases, season of drug intoxication, and age, all of which exhibited significant differences between those who did and did not attempt suicide again. The presence of psychiatric diseases (odds ratio [OR] = 1.99, 95% confidence interval [CI] = 1.04~3.80), intoxication occurring in the fall (vs. spring; OR = 3.35, 95% CI = 1.28~8.75), and age ≥ 65 (vs. those under the age of 18; OR = 12.96, 95% CI = 2.02~83.17). The regression model was found to be statistically significant (F = 30.01, p < .001), and the coefficient of determination of Cox and Snell, which represents the explanatory power of the model, was 12.0%. Conclusion: This study suggests that to prevent repeated suicide attempts, it is necessary to develop a tool to evaluate the risk of suicide, use it to evaluate the risk of suicide, and then manage individuals accordingly.

• 한국가축번식학회지
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• 제25권4호
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• pp.295-304
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• 2001

양적형질 유전자 좌위 (QTL)의 탐색과 이들의 발현 양상 규명을 위해 Berkshire종과 Yorkshire종 간의 교배를 통해 생산된 F$_2$ 실험집단에서 regression interval mapping이 이루어졌다. 모두 525마리의 F$_2$ 자손들에서 일당 증체량, 평균 등지방 두께, 배장근 단면적이 표현형으로 조사되어 분석에 이용되었으며 모돈의 번식능력에 관련된 QTL 존재 여부 추정을 위해 간접 형질로 인정되고 있는 생시체중과 이유 시 체중을 분석에 포함하였다. 양적형질의 분리 여부를 추론하기 위하여 돼지의 2번 염색체에서 8종의 microsatellite 표지인자가 선택되어 유전자형이 조사되었다. 각각의 유전적 모델에서 산출된 통계량으로부터 QTL 존재 여부와 특정 QTL 발현 양상에 대한 여부를 나타낼 수 있는 인정되는 수준의 type I 오차율을 제어할 수 있는 임계값 (threshold)을 permutation test에 의해 제시하였다. QTL의 존재와 그 QTL의 Imprinting 여부는 부계와 모계를 통해 원가계 1세대의 대립유전자가 전달되는 과정에서 발현되는 특성을 분리시키는 통계적 의형을 설정하여 검정 통계량을 산출하였다. 분석에 이용된 3가지 형질과 연관된 3종류의 QTL 존재 가능성을 돼지의 2번 염색체에서 확인하였으며, 이들 중 평균 등지방 두께와 배장근 단면적에 각각 영향을 미칠 것으로 추론된 2종류의 QTL 발현은 정상적인 Mendelian 유전양식을 따르지 않고 imprinting된다는 증거를 얻어냈다. 또한 이들 imprinting되는 QTL은 이미 imprinting 표현 양식을 가진다고 알려진 IGF II 유전자의 위치와 거의 동일한 염색체강의 지점에서 부계로 전달되는 QTL만이 발현되는 특징을 보이는 것으로 밝혀졌다. 한편 Mendelian 모형과 imprinting 모형 모두에서 유의적인 임계값 이상을 보이는 검정 통계량이 산출된 일당 증체량 연관 QTL은 두 모형간의 적정성 분석을 위한 검정을 퐁해 Mendelian 양식을 따른 것으로 최종 확인되었다.