• Title/Summary/Keyword: Size heterogeneity

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Pro Variant of TP53 Arg72Pro Contributes to Gastric Cancer Risk in Asians: Evidence from a Meta-analysis

  • Su, Xiu-Li;Jin, Jian-Jun
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.3
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    • pp.915-921
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    • 2012
  • Background: Previous studies investigating the association between TP53 Arg72Pro polymorphism and gastric cancer (GC) risk in Asian population have reported controversial results. Thus, a meta-analysis was performed. Methods: A comprehensive literature search was conducted and 17 case-control studies were finally included, involving a total of 5,990 GC cases and 6,812 controls. Subgroup analyses were performed by the sample size. Results: Meta-analysis of all 17 studies showed variant genotypes of TP53 Arg72Pro to be associated with an elevated GC risk in three genetic comparison models ($OR_{Pro\;vs.\;Arg}$=1.13, 95%CI 1.03-1.25, $P_{OR}$=0.01; $OR_{Homozygote\;comparison\;model}$=1.33, 95%CI 1.07-1.64, $P_{OR}$=0.009; $OR_{Dominant\;genetic\;model}$=1.13, 95%CI 1.05-1.22, $P_{OR}$=0.002). Besides, a more obvious association was observed after the heterogeneity was decreased (all P values less than 0.001). This association was further identified by both subgroup and sensitivity analyses. Conclusions: This meta-analysis suggests the Pro variant of TP53 Arg72Pro contributes to gastric cancer risk in Asians.

A Consumer-Oriented Study of Price Increases and Downsizing : Focused on Roles of Competitor's Pricing Strategy and Risk-Aversion (가격인상과 용량감소에 관한 소비자 관점의 비교 연구 : 경쟁사 가격전략과 위험회피성향을 중심으로)

  • Kim, Hye Young;Kang, Yeong Seon
    • Korean Management Science Review
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    • v.32 no.3
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    • pp.55-70
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    • 2015
  • The main objective of this study is to investigate the moderating roles of the competitor's pricing strategy and the degree of consumer's risk-aversion on perceived risk and perceived benefit in responding to price increases and package downsizing. Based on Prospect Theory, several prior researches find that consumers perceive increased price as more loss than package downsizing and perceive package downsizing as more benefit than increased price. We extend these behavioral economics approach using the reference effect of competitor's pricing strategy. We focus on consumer heterogeneity on risk-aversion, measure the degree of consumer's risk-aversion, and divide the consumers into two groups of high levels of risk-aversion vs. low levels of risk-aversion. We find that the firm's pricing strategies of both price increases and package downsizing do not significantly influence the perceived benefit for relatively low risk-aversion consumers. We find that when the firm reduce the package size, relatively high risk-aversion consumers perceived more benefit and had higher purchase intention compared to price increases. We also find that the competitor's pricing strategies do not significantly influence the consumer's response for relatively low risk-aversion consumers. For relatively high risk-aversion consumers, they perceived more loss when the firm has different pricing strategy from the competitor's.

Evaluation Method of Rock Characteristics using X-ray CT images (X-ray CT 이미지를 이용한 암석의 특성 평가 방안)

  • Kim, Kwang Yeom;Yun, Tae Sup
    • Tunnel and Underground Space
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    • v.29 no.6
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    • pp.542-557
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    • 2019
  • The behavior of rock mass is influenced by its microscopic feature of internal structure generating from forming and metamorphic process. This study investigated a new methodology for characterization of rock based on the X-ray CT (computed tomography) images reflecting the spatial distribution characteristics of internal constituent materials. The X-ray image based analysis is capable of quantification of heterogeneity and anisotropy of rock fabric, size distribution and shape parameter analysis of rock mineral grains, fluid flow simulation based on pore geometry image and roughness evaluation of unexposed joint surface which are hardly acquired by conventional rock testing methods.

Development of a Hybrid Watershed Model STREAM: Model Structures and Theories (복합형 유역모델 STREAM의 개발(I): 모델 구조 및 이론)

  • Cho, Hong-Lae;Jeong, Euisang;Koo, Bhon Kyoung
    • Journal of Korean Society on Water Environment
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    • v.31 no.5
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    • pp.491-506
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    • 2015
  • Distributed models represent watersheds using a network of numerous, uniform calculation units to provide spatially detailed and consistent evaluations across the watershed. However, these models have a disadvantage in general requiring a high computing cost. Semi-distributed models, on the other hand, delineate watersheds using a simplified network of non-uniform calculation units requiring a much lower computing cost than distributed models. Employing a simplified network of non-uniform units, however, semi-distributed models cannot but have limitations in spatially-consistent simulations of hydrogeochemical processes and are often not favoured for such a task as identifying critical source areas within a watershed. Aiming to overcome these shortcomings of both groups of models, a hybrid watershed model STREAM (Spatio-Temporal River-basin Ecohydrology Analysis Model) was developed in this study. Like a distributed model, STREAM divides a watershed into square grid cells of a same size each of which may have a different set of hydrogeochemical parameters reflecting the spatial heterogeneity. Like many semi-distributed models, STREAM groups individual cells of similar hydrogeochemical properties into representative cells for which real computations of the model are carried out. With this hybrid structure, STREAM requires a relatively small computational cost although it still keeps the critical advantage of distributed models.

Association between neonatal jaundice and autism spectrum disorders among children: a meta-analysis

  • Jenabi, Ensiyeh;Bashirian, Saeid;Khazaei, Salman
    • Clinical and Experimental Pediatrics
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    • v.63 no.1
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    • pp.8-13
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    • 2020
  • Autism spectrum disorder is a common neurodevelopmental disorder with an unknown etiology. The correlation between neonatal jaundice and the risk of developing autism spectrum disorder was investigated previously. Some studies showed significant associations, whereas others demonstrated no association. In this meta-analysis, we pooled the results of observational studies to examine the association between neonatal jaundice and the risk of autism spectrum disorder among children. We identified all studies published through April 2018 by conducting a literature search using Web of Science, PubMed, and Scopus databases as well as the reference lists of the retrieved studies. The pooled odds ratios (ORs), rate ratio (RR), and their 95% confidence intervals (CIs) were calculated as random effect estimates of association among studies. We conducted a subgroup analysis to explore any potential sources of intergroup heterogeneity. The pooled estimates of OR and RR showed a considerable correlation between neonatal jaundice and ASD among children (OR, 1.35; 95% CI, 1.02-1.68) and (RR, 1.39; 95% CI, 1.05-1.74). A larger effect size was shown in the pooled estimated crude OR than in the adjusted OR (1.75 [0.96-2.54] vs. 1.19 [1.07-1.30]). This study showed that neonatal jaundice may be associated with ASD and may increase the risk of ASD among children.

Modified GSS Algorithm for Heterogeneous Cluster (이기종 클러스터를 위한 수정된 GSS 알고리즘)

  • 구본근
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2002.11a
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    • pp.405-408
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    • 2002
  • Cluster is the cost-effective parallel processing environment, and consists of the off-the-shelf computers connected by the computer networks. The characteristics of cluster are the node heterogeneity, the variety of node load, and the variety of network load. Because these characteristics influence the performance of parallel program executions, the load sharing for cluster is important, and by using the proper load sharing strategy, we can reduce the execution time of parallel programs. In this paper, we propose modified GSS algorithm, aGSS. In the proposed load sharing algorithms aGSS, the size of tasks are decided using the BogoMTPS of node. From the result of out experiments, we conclude that the proposed aGSS algorithm is effective in the heterogeneous cluster.

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Effectiveness of the Intervention Programs for Pressure Ulcer Prevention in Intensive Care Units : A Meta-analysis (중환자실의 욕창 예방 중재 프로그램의 효과 : 메타 분석)

  • Kang, Hyunwook;Ko, Ji Woon
    • Journal of Korean Critical Care Nursing
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    • v.11 no.1
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    • pp.67-78
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    • 2018
  • Purpose : A meta-analysis was conducted to identify the effectiveness of strategies designed to prevent the incidence and prevalence of pressure ulcers in intensive care units (ICUs). Method : The search strategy was designed to retrieve studies both published and unpublished between 2007 and 2017 including studies in English across PubMed and CINAHL, as well as in Korean across RISS, DBPia, NDSL, KISS, and NAL. All adult ICU participants were 18 years or over. Inclusion criteria were randomized controlled trials, quasi-experimental and comparative studies. Two independent reviewers conducted quality assessments of the included studies by Scottish Intercollegiate Guidelines Network. A Review Manager 5 was used to analyze effect sizes and to identify possible sources of heterogeneity among the studies. Results : The odds ratio (OR) effect sizes were all statistically significant. The OR of total effect size was 0.30(95% CI: 0.19, 0.47), care bundle was 0.37(95% CI: 0.24, 0.57), position change was 0.45(95% CI: 0.10, 2.08), and a silicone border foam dressing was 0.14 (95% CI: 0.07, 0.29). Conclusion : The preventive interventions for patients in the ICUs have positive impacts on reducing the incidence of pressure ulcers.

Free vibrations analysis of arbitrary three-dimensionally FGM nanoplates

  • Dehshahri, Kasra;Nejad, Mohammad Zamani;Ziaee, Sima;Niknejad, Abbas;Hadi, Amin
    • Advances in nano research
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    • v.8 no.2
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    • pp.115-134
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    • 2020
  • In this paper, the free vibrations analysis of the nanoplates made of three-directional functionally graded material (TDFGM) with small scale effects is presented. To study the small-scale effects on natural frequency, modified strain gradient theory (MSGT) has been used. Material properties of the nanoplate follow an arbitrary function that changes in three directions along the length, width and thickness of the plate. The equilibrium equations and boundary conditions of nanoplate are obtained using the Hamilton's principle. The generalized differential quadrature method (GDQM) is used to solve the governing equations and different boundary conditions for obtaining the natural frequency of nanoplate made of three-directional functionally graded material. The present model can be transformed into a couple stress plate model or a classic plate model if two or all parameters of the length scales set to zero. Finally, numerical results are presented to study the small-scale effect and heterogeneity constants and the aspect ratio with different boundary conditions on the free vibrations of nanoplates. To the best of the researchers' knowledge, in the literature, there is no study carried out into MSGT for free vibration analysis of FGM nanoplate with arbitrary functions.

A Meta-Analysis of the meets of Aromatherapy on Psychological Variables in Nursing (아로마테라피 간호중재의 정신심리적 효과 메타분석)

  • Roh, Kook-He;Park, Hyeoun-Ae
    • Research in Community and Public Health Nursing
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    • v.20 no.2
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    • pp.113-122
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    • 2009
  • Purpose: The purpose of this study is to explore the effect of aromatherapy on anxiety, depression, and stress. Methods:Medical and nursing literature databases were searched to identify studies comparing aromatherapy with a control group. Results: Thirty-one studies published till September 2008 were included in the analysis. Twenty-two studies showed that aromatherapy generally had positive effects on the anxiety level (ES: 0.61). Thirteen studies showed that aromatherapy has significantly decreased the depression level (ES: 0.91). Seven studies showed that aromatherapy had positive effect on the stress level (ES: 0.78). Further analysis found that aromatherapy was more effective for normal population than for patients group with anxiety and stress. On the contrary, aromatherapy was more effective for patients group than for general population with depression. Conclusion: Aromatherapy had positive effect on anxiety, depression and stress level. But there was no sufficient evidence to show the two different aromatherapy methods and two different period of aromatherapy had different effects due to small sample size and heterogeneity of sample. And it was needed to perform follow-up and further comparative studies.

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Effect of confining stress on representative elementary volume of jointed rock masses

  • Wu, Na;Liang, Zhengzhao;Li, Yingchun;Qian, Xikun;Gong, Bin
    • Geomechanics and Engineering
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    • v.18 no.6
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    • pp.627-638
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    • 2019
  • Estimation of representative elementary volume (REV) of jointed rock masses is critical to predict the mechanical behavior of field-scale rock masses. The REV of jointed rock masses at site is strongly influenced by stress state. The paper proposed a method to systematically studied the influence of confining stress on the REV of jointed rock masses with various strengths (weak, medium and strong), which were sourced from the water inlet slope of Xiaowan Hydropower Station, China. A finite element method considering material heterogeneity was employed, a series of two-dimensional (2D) models was established based on the Monte-Carlo method and a lot of biaxial compressive tests were conducted. Numerical results showed that the REV of jointed rock masses presented a step-like reduction as the normalized confining stress increased. Confining stress weakened the size effect of jointed rock masses, indicating that the REV determined under uniaxial compression test can be reasonably taken as the REV of jointed rock masses under complexed in-situ stress environment.