• Journal of Nutrition and Health
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• 제50권5호
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• pp.437-446
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• 2017

'계피' 건조분말 및 물추출물의 혈당 개선 기능성을 평가하기 위하여 메타 분석을 실시하였다. 2017년 5월을 기준으로 DB 검색을 통해 4,688건의 자료를 수집하여, 선정/제외 기준에 따라 선별한 결과 총 14건 (n = 709)의 연구가 분석에 포함되었다. 건조분말의 경우 하루 1~6 g씩 섭취하였을 때, 공복혈당은 -1.55 mmol/L, 식후 혈당의 곡선하면적은 $-51.8mmol/L{\cdot}min$ 수준으로, 물추출물은 하루 0.1~0.5 g씩 섭취시 공복혈당이 -0.76 mmol/L 수준으로 개선시켰으며, 당화혈색소에는 영향이 없는 것으로 분석되었다.

• 한국심리학회지 : 문화 및 사회문제
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• 제30권3호
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• pp.239-265
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• 2024

본 연구는 자살 관련 행동에 대해 전통적인 예측 모형(기법)과 머신러닝 알고리즘을 활용한 연구의 예측력을 비교하기 위한 목적에서 수행되었다. 따라서 체계적 리뷰 수준에서 벗어나 메타분석을 통해 과학적으로 두 가지 기법의 예측력에 대해 살펴보고, 지역적인 수준에서 특히 국내 연구를 통해 알 수 있는 변인들을 분석하여 추후 자살 관련 행동 예측 연구에 도움을 주고자 하였다. 이를 위해 머신러닝을 사용한 연구 50개와 전통적 기법을 활용한 연구 74개로 총 124개의 문헌이 메타분석에 포함되었다. 연구 결과 전통적 기법을 활용한 연구들의 통합 AUC는 .770으로 머신러닝을 활용한 연구들의 통합 AUC값인 .853보다 낮은 것으로 나타났다. 특히 아시아권의 연구(AUC = .944)가 서양(AUC = .820)과 한국(AUC = .864)의 연구에 비해 높은 정확도를 나타내었다. 국내 연구에서의 조절효과를 추가적으로 분석한 결과 남성의 비율이 많을수록, 예측 대상이 자살 시도일수록 예측 정확도가 높았으며, 예측 대상이 자살 사망일수록, 그리고 신경망분석(Neural Network)을 활용한 연구일수록 예측 정확도가 낮았다. 본 연구는 자살 관련 행동의 예측에 대한 다양한 연구결과를 종합하고, 머신러닝을 활용한 예측의 효과성을 검증하는 한편, 국내에서 활용가능한 변인을 탐색하는 데 그 의의가 있다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권8호
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• pp.3233-3239
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• 2015

Background: Whether depression causes increased risk of the development of breast cancer has long been debated. We conducted an updated meta-analysis of cohort studies to assess the association between depression and risk of breast cancer. Materials and Methods: Relevant literature was searched from Medline, Embase, Web of Science (up to April 2014) as well as manual searches of reference lists of selected publications. Cohort studies on the association between depression and breast cancer were included. Data abstraction and quality assessment were conducted independently by two authors. Random-effect model was used to compute the pooled risk estimate. Visual inspection of a funnel plot, Begg rank correlation test and Egger linear regression test were used to evaluate the publication bias. Results: We identified eleven cohort studies (182,241 participants, 2,353 cases) with a follow-up duration ranging from 5 to 38 years. The pooled adjusted RR was 1.13(95% CI: 0.94 to 1.36; $I^2=67.2%$, p=0.001). The association between the risk of breast cancer and depression was consistent across subgroups. Visual inspection of funnel plot and Begg's and Egger's tests indicated no evidence of publication bias. Regarding limitations, a one-time assessment of depression with no measure of duration weakens the test of hypothesis. In addition, 8 different scales were used for the measurement of depression, potentially adding to the multiple conceptual problems concerned with the definition of depression. Conclusions: Available epidemiological evidence is insufficient to support a positive association between depression and breast cancer.

• 대한수학교육학회지:수학교육학연구
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• 제22권3호
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• pp.331-352
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• 2012

이 연구는 비례문제 해결에 영향을 주는 인지적 변인이 무엇인지 확인하는 것을 궁극적인 목적으로 한다. 이를 위해 비례 문제를 구조화 정도에 따라 잘-구조화된 문제, 구조화된 문제, 비-구조화된 문제로 분류하고, 이론적 고찰을 통해 비례문제 해결에 영향을 주는 인지적 변인으로 사실 알고리즘 지식, 개념적 지식, 문제유형 지식, 양의 변화 인식, 메타인지를 추출하였다. 중다회귀분석 방법을 사용해 구조화 정도가 다른 문제를 해결하는데 유의하게 영향을 주는 인지적 변인이 무엇인지를 분석하였다. 분석 결과 구조화 정도가 다른 문제를 해결하는데 서로 다른 인지적 변인이 영향을 주었다. 즉 잘-구조화된 문제 해결에는 사실 알고리즘 지식과 문제유형 지식, 그리고 구조화된 문제 해결에는 개념적 지식, 문제유형지식, 양의 변화 인식, 마지막으로 비-구조화된 문제해결에는 메타조절, 개념적 지식, 양의 변화 인식, 문제유형지식이 영향을 주었다. 이처럼 문제 유형에 따라 다른 인지적 변인이 영향을 미치기 때문에, 수학수업에서는 문제 유형에 따라 다른 교수학습 방법과 다른 평가 틀을 적용할 필요가 있으며, 더불어 학생들의 비례 문제 해결 능력을 계발하기 위해서는 수학 수업에서 구조화된 문제와 비-구조화된 문제를 적극 활용할 필요가 있다는 결론을 도출할 수 있었다.

• Journal of Animal Science and Technology
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• 제56권2호
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• pp.5.1-5.5
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• 2014

The objectives of this study were thus to identify most significant factors that determine milk component yield (MCY) using a meta-analysis and, if possible, to develop equations to predict MCY using variables that can be easily measured in the field. A literature database was constructed based on the research articles published in the Journal of Dairy Science from Oct., 2007 till May, 2010. The database consisted of a total of 442 observed means for MCY from 118 studies. The candidate factors that determine MCY were those which can be routinely measured in the field (e.g. DMI, BW, dietary forage content, chemical composition of diets). Using a simple linear regression, the best equations for predicting milk fat yield(MFY) and milk protein yield (MPY) were $MFY=0.351({\pm}0.068)+0.038({\pm}0.003)$ DMI ($R^2=0.27$), and $MPY=0.552({\pm}0.071)+0.031({\pm}0.002)DMI-0.004({\pm}0.001)$ FpDM (%, forage as a percentage of dietary DM) ($R^2=0.38$), respectively. The best equation for predicting milk fat content (%) explained only 12% of variations in milk fat content, and none of a single variable can explain more than 5% of variations in milk protein content. We concluded that among the tested variables, DMI was the only significant factor that affects MFY and both DMI and FpDM significantly affect MPY. However, predictability of linear equations was relatively low. Further studies are needed to identify other variables that can predict milk component yield more accurately.

• 대한간호학회지
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• 제49권6호
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• pp.655-676
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• 2019

Purpose: The purpose of this study was to investigate the effects of aromatherapy on sleep quality. Methods: This is a systematic review of randomized controlled trial studies (PROSPERO registration number CRD42017064519). In this study, the PICO were adults and the elderly, aromatherapy intervention, a comparative intervention with the control and placebo oil groups, and sleep. The selected articles were in English, Korean, and Chinese. Results: The results of the meta-analysis showed that the effect sizes of the experimental group were 1.03 (n=763, SMD=1.03, 95% CI 0.66 to 1.39) (Z=5.47, p<.001). In the aromatherapy intervention group, the effect size of sleep was statistically significant (Q_B=9.39, df=2, p=.009), with a difference of 0.77 for inhalation, 1.12 for oral intake and 2.05 for massage. A post-analysis showed that the effect of massage on sleep was significantly greater than the inhalation method. The regression coefficient of the intervention period, B=0.01 (Z=1.43, p=.154), also showed that the longer the intervention period, the larger the effect size; however, it was not statistically significant. Conclusion: A total of 23 literature analyses showed that aromatherapy is effective in improving quality of sleep, and the massage method is more effective in improving quality of sleep than the inhalation method. A meta-ANOVA showed that the aromatherapy intervention affected the high heterogeneity of the effect size. Thus, future research with stricter control in methods and experimental procedures is necessary.

• Smart Structures and Systems
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• 제31권2호
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• pp.113-130
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• 2023

Hybrid simulation (HS) has attracted community attention in recent years as an efficient and effective experimental technique for structural performance evaluation in size-limited laboratories. Traditional hybrid simulations usually take deterministic properties for their numerical substructures therefore could not account for inherent uncertainties within the engineering structures to provide probabilistic performance assessment. Reliable structural performance evaluation, therefore, calls for stochastic hybrid simulation (SHS) to explicitly account for substructure uncertainties. The experimental design of SHS is explored in this study to account for uncertainties within analytical substructures. Both computational simulation and laboratory experiments are conducted to evaluate the pseudo-random Sobol sequence for the experimental design of SHS. Meta-modeling through polynomial chaos expansion (PCE) is established from a computational simulation of a nonlinear single-degree-of-freedom (SDOF) structure to evaluate the influence of nonlinear behavior and ground motions uncertainties. A series of hybrid simulations are further conducted in the laboratory to validate the findings from computational analysis. It is shown that the Sobol sequence provides a good starting point for the experimental design of stochastic hybrid simulation. However, nonlinear structural behavior involving stiffness and strength degradation could significantly increase the number of hybrid simulations to acquire accurate statistical estimation for the structural response of interests. Compared with the statistical moments calculated directly from hybrid simulations in the laboratory, the meta-model through PCE gives more accurate estimation, therefore, providing a more effective way for uncertainty quantification.

• Korean Journal of Radiology
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• 제21권7호
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• pp.908-918
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• 2020

Objective: To categorize the radiological patterns of recurrence after bevacizumab treatment and to derive the pooled proportions of patients with recurrent malignant glioma showing the different radiological patterns. Materials and Methods: A systematic literature search in the Ovid-MEDLINE and EMBASE databases was performed to identify studies reporting radiological recurrence patterns in patients with recurrent malignant glioma after bevacizumab treatment failure until April 10, 2019. The pooled proportions according to radiological recurrence patterns (geographically local versus non-local recurrence) and predominant tumor portions (enhancing tumor versus non-enhancing tumor) after bevacizumab treatment were calculated. Subgroup and meta-regression analyses were also performed. Results: The systematic review and meta-analysis included 17 articles. The pooled proportions were 38.3% (95% confidence interval [CI], 30.6-46.1%) for a geographical radiologic pattern of non-local recurrence and 34.2% (95% CI, 27.3-41.5%) for a non-enhancing tumor-predominant recurrence pattern. In the subgroup analysis, the pooled proportion of non-local recurrence in the patients treated with bevacizumab only was slightly higher than that in patients treated with the combination with cytotoxic chemotherapy (34.9% [95% CI, 22.8-49.4%] versus 22.5% [95% CI, 9.5-44.6%]). Conclusion: A substantial proportion of high-grade glioma patients show non-local or non-enhancing radiologic patterns of recurrence after bevacizumab treatment, which may provide insight into surrogate endpoints for treatment failure in clinical trials of recurrent high-grade glioma.

• Korean Journal of Radiology
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• 제21권6호
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• pp.684-694
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• 2020

Objective: The purpose was to review the diagnostic performance of the length of tumor capsular contact (LCC) on magnetic resonance imaging (MRI) for detecting prostate cancer extraprostatic extension (EPE). Materials and Methods: PubMed and EMBASE databases were searched up to March 24, 2019. We included diagnostic accuracy studies that evaluated LCC on MRI for EPE detection using radical prostatectomy specimen histopathology as the reference standard. Quality of studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Sensitivity and specificity were pooled and graphically presented using hierarchical summary receiver operating characteristic (HSROC) plots. Meta-regression and subgroup analyses were conducted to explore heterogeneity. Results: Thirteen articles with 2136 patients were included. Study quality was generally good. Summary sensitivity and specificity were 0.79 (95% confidence interval [CI] 0.73-0.83) and 0.67 (95% CI 0.60-0.74), respectively. Area under the HSROC was 0.81 (95% CI 0.77-0.84). Substantial heterogeneity was present among the included studies according to Cochran's Q-test (p < 0.01) and Higgins I² (62% and 86% for sensitivity and specificity, respectively). In terms of heterogeneity, measurement method (curvilinear vs. linear), prevalence of Gleason score ≥ 7, MRI readers' experience, and endorectal coils were significant factors (p ≤ 0.01), whereas method to determine the LCC threshold, cutoff value, magnet strength, and publication year were not (p = 0.14-0.93). Diagnostic test accuracy estimates were comparable across all assessed MRI sequences. Conclusion: Greater LCC on MRI is associated with a higher probability of prostate cancer EPE. Due to heterogeneity among the studies, further investigation is needed to establish the optimal cutoff value for each clinical setting.

• Journal of Preventive Medicine and Public Health
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• 제31권1호
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• pp.91-103
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• 1998

성층권의 오존층 파괴로 수반되는 부작용에는 우주의 자외선이 차단되지 않고 지구표면에까지 도달하는 것을 들 수 있다. 이로 인하여 생태계 파괴를 비롯하여 기후이상 및 인체 건강장애 발생의 가능성이 높아진다고 알려져 있다. 특히 자외선 노출로 인한 피부암 발생에 관한 여러 연구결과가 보고 되었으며 이에 대한 종합적이고 신뢰성 있는 재평가 필요성이 대두되었으며 유사한 연구의 국내 수행이 제시되는 때이다. 이에 메타분석이라는 방법을 통하여 신뢰성있는 BAF 값을 추정하여 보고 이 지수를 국내 자료에 적용하여 국내 피부암 발생의 변화 양상을 자외선 증가와 함께 추정하여 보았다. 3개국의 자료를 일원화하여 추정된 UVB 계수는 지수함수 모델에 의해서는 $2.07\times10^{-6}$으로, 멱함수 모델에 의해서는 2.49로 산출되었으며, 이들 모두 통계적으로 유의한 것으로 나타났으며, 이 계수로부터 BAF 값을 추정한 결과, 서울 일부 지역에서의 UVB 조사량이 1% 증가되면, 피부암 발생률은 지수함수 모델에서는 1.90%, 멱함수 모델에서는 2.51%가 증가되는 것으로 산출되었으며, 이 연구에서 적용한 메타분석의 방법으로 제시된 위해도는 비교적 신뢰도가 높을 것으로 추정된다. 현재 우리나라에서의 비흑색종 피부암 발생율이 백만명당 11명이라고 가정할 때, UVB 조사량이 1% 증가됨으로 인해 국내 비흑색종 피부암 발생율은 백만명당 11.1명$\sim$11.3명으로 증가되는 것으로 예측된다. 이렇게 낮은 수준의 위해도에도 불구하고 자외선 노출이 피부암 발생의 원인적 요인이라는 것이 밝혀진 지금, 이에 대한 불필요한 노출을 가능한 삼가고 계속적인 관심을 두어야 할 것이다.