• Title/Summary/Keyword: heterogeneity

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The Exonuclease 1 Glu589Lys Gene Polymorphism and Cancer Susceptibility: Evidence Based on a Meta-analysis

  • Bayram, Suleyman
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.6
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    • pp.2571-2576
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    • 2014
  • Background: Published studies on the association between the exonuclease 1 (EXO1) Glu589Lys polymorphism and cancer susceptibility have yielded conflicting results. Thus, a meta-analysis of published studies was performed to assess the possible association. Materials and Methods: All eligible case-control studies published up to January 2013 on the association between the EXO1 Glu589Lys polymorphism and cancer susceptibility were identified by searching PubMed, Web of Science, Science Direct and hand search. Either fixed-effect or random-effect models were used to calculate pooled odds ratios (ORs) with 95% confidence intervals (CIs) using the Comprehensive Meta-Analysis software version 2.2. Results: A total of 4,391 cancer cases and 4,339 controls from 10 studies were included. Overall, no significant association between the EXO1 Glu589Lys polymorphism and cancer susceptibility was observed in either genetic model. However; in subgroup analyses by cancer type, a significant association between EXO1 Glu589Lys and lung cancer risk was found (Lys vs Glu: OR=1.23, 95%CI=1.07-1.41, $p_{heterogeneity}$=0.05). Further, subgroup analysis by ethnicity indicated that there was a statistically increased cancer risk in Asians (Lys vs Glu: OR=1.42, 95%CI=1.30-1.55, $p_{heterogeneity}$=0.07; Lys/Lys vs Glu/Glu: OR=1.93, 95%CI=1.20-3.12, $p_{heterogeneity}$=0.01; Lys/Lys+Glu/Lys vs Glu/Glu: OR=1.52, 95%CI=1.37-1.68, $p_{heterogeneity}$=0.42; Lys/Lys vs Glu/Lys+Glu/Glu: OR=1.68, 95%CI=1.07-2.65, $p_{heterogeneity}$=0.02). However, significant association was absent in Caucasians. Conclusions: This meta-analysis suggests, for the first time, that the EXO1 Glu589Lys polymorphism is not associated with overall cancer susceptibility, although marginal associations were found for lung cancer and Asian subgroups. Additional well-designed studies with larger sample size focusing on different ethnicities and cancer types are needed to confirm these findings.

The Interleukin-18 Promoter -607C>A Polymorphism Contributes to Nasopharyngeal Carcinoma Risk: Evidence from a Meta-analysis Including 1,886 Subjects

  • Guo, Xu-Guang;Xia, Yong
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.12
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    • pp.7577-7581
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    • 2013
  • The interleukin-18 promoter -607C>A gene polymorphism may be related to nasopharyngeal carcinoma (NPC) risk but the results of individual studies remain conflicting. A meta-analysis including 1,886 subjects from five individual studies was therefore performed to provide a more accurate estimation. Pooled odds ratios (ORs) and their corresponding 95% confidence intervals (95% CIs) were evaluated by fixed- or random-effects models. A significant relationship between interleukin-18 promoter -607C>A gene polymorphism and NPC was found in a dominant genetic model (OR: 1.351, 95% CI: 1.089-1.676, P=0.006, $P_{heterogeneity}$=0.904), a homozygote model (OR: 1.338, 95% CI: 1.023-1.751, P=0.034, $P_{heterogeneity}$=0.863), and a heterozygote model (OR: 1.357, 95% CI: 1.080-1.704, P=0.009, $P_{heterogeneity}$=0.824). No significant association was detected in either an allelic genetic model (OR: 1.077, 95% CI: 0.960-1.207, 0.207, $P_{heterogeneity}$=0.844) or a recessive genetic model (OR: 1.093, 95% CI: 0.878-1.361, P=0.425, $P_{heterogeneity}$=0.707). In conclusion, a significant association was found between interleukin-18 promoter -607C>A gene polymorphism and NPC risk. Individuals with the C allele of interleukin-18 promoter -607C>A gene polymorphism have a higher risk of NPC development.

A Study on the Heterogeneity in Multi-player VR Games : focused on (멀티플레이어 가상현실 게임에 나타난 비균질성 연구 : <더 플레이룸 VR>을 중심으로)

  • Park, Eun-Kyung;Nam, Yang-Hee
    • Journal of Korea Game Society
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    • v.16 no.6
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    • pp.151-162
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    • 2016
  • The purpose of this paper is to identify the significance of heterogeneity in multi-player VR games. Heterogeneity is a concept of multi-player mode that a game uses the immersive VR and non-immersive system at the same time. As immersive VR device has become more commercial, multi-player VR games try to use heterogeneity strategically. is the best example to explain a new phenomenon, so this paper analyses by using a revised and reinforced MDA framework. As a result, we can find heterogeneity concept not only in the separation of player's interface, but also in the division of play patterns and experiences within a game itself.

A Study on Preference Heterogeneity of Economic Valuation for the Washland of Upo Wetland - Development of Waterfront Resources - (우포늪 천변저류지의 경제적 가치평가에 대한 선호이질성 연구 - 수변관광자원의 선택적 개발 -)

  • Yoo, Byong Kook;Kim, Hung Soo;Ju, Dug
    • Journal of Wetlands Research
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    • v.15 no.3
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    • pp.357-366
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    • 2013
  • This study investigates to explain preference heterogeneity of respondents for economic valuation in washland of Upo wetland using Mixed Logit Model and Latent Class Model. Mixed Logit Model showed respondent heterogeneity in the attributes of wetland area and funds as well as some alternatives violated IIA assumption. 2-class Latent Class Model for respondents were used to explain the sources of the heterogeneity. Class 1 respondents who are located relatively close to Upo wetland had more experience and knowledge of Upo wetland and better understood the information suggested in the questionnaire than class 2 respondents in mostly metropolitan area of Seoul, Incheon.

The Design of Data Grid Wrapper for Integrated Retrieve based on XMDR (XMDR 기반의 통합 검색을 위한 데이터 그리드 Wrapper 설계)

  • Hwang, Chi-Gon;Jung, Kye-Dong;Choi, Young-Keun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.12 no.5
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    • pp.921-929
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    • 2008
  • Recently, many researches have been conducted to solve data heterogeneity as a way for data integration. The elements of the system that we suggest are an XMDR wrapper and XMDR Repository. XMDR wrapper solves the heterogeneity of the existing system by creating the interface based on the standard information of XMDR, and performing the inter-conversion between global XMDR query and local query using mapping data on standard information and local schema. XMDR Repository are composed of XMDR which manages the mapping data on standard information and local schema, and of Proxy DB which saves the accomplished results. With XMDR wrapper and XMDR Repository, users can use the same interface, and they need not conduct repeated queries since XMDR wrapper not only solves the heterogeneity of the schema using the meta-semantic ontology of XMDR, but also considers the heterogeneity accompanying the meaning of the value through instance semantic ontology. Therefore, in this paper we suggest the grid wrapper for the solution of data heterogeneity and efficient data integration.

Effect of Aflatoxin on Feed Conversion Ratio in Broilers: A Meta-analysis

  • Suganthi, R. Umaya;Suresh, K.P.;Parvatham, R.
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.12
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    • pp.1757-1762
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    • 2011
  • Aflatoxins are natural contaminants of poultry feeds and feed ingredients and cause liver damage, immunosuppression, reduction in performance and mortality in broilers. A number of studies have been carried out to study the effects of aflatoxin on feed conversion ratio in broilers. The results on feed conversion ratio of 10 research articles in broilers fed with aflatoxin from first day of age to six weeks of age were compiled and were subjected to meta-analysis. Chi-square test and $Tau^2$ (heterogeneity co-efficient) were applied to test for significance of heterogeneity of studies. To integrate results, fixed effect model by Inverse Variance method (IV method) was used when heterogeneity was insignificant and otherwise random effect model by DerSimonian and Laird Method (DL method) was used. The results of meta-analysis showed that the adverse effect of aflatoxin on feed conversion ratio at the end of first week was negligible, second week was medium and third to six weeks was very large.

Fuel Composition Heterogeneity Effect for DUPIC Core

  • Park, Hangbok;Bo W. Rhee;Park, Hyunsoo
    • Proceedings of the Korean Nuclear Society Conference
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    • 1995.10a
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    • pp.109-114
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    • 1995
  • A preliminary study of the heterogeneity effect of spent P% fuel in CANDU was made using a reduced spent PWR fuel data base. The instantaneous core simulation has shown that the refueling ripple in the CANDU reactor is large if the spent PWR fuel is directly used. But the fuel heterogeneity effect can be reduced appreciably by blending spent PWR fuel with a small amount of fresh UO$_2$. The refueling simulation has shown that the operating margins of 6.0% and 8.7% are achievable for the peak channel and bundle powers, respectively, with the blended fuel.

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Zn(II)porphyrin Helical Arrays: A Strategy to Overcome Conformational Heterogeneity by Host-Guest Chemistry

  • Yoon, Zin-Seok;Easwaramoorthi, Shanmugam;Kim, Dong-Ho
    • Bulletin of the Korean Chemical Society
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    • v.29 no.1
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    • pp.197-201
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    • 2008
  • Conformational heterogeneity of directly linked multiporphyrin arrays with larger molecular length retards their utilities in practical applications such as two-photon absorption and molecular photonic wire. In this regard, here we adopted a way to overcome the conformational heterogeneity through hydrogen bonding by selective binding of meso aryl substituents of porphyrins (host) with urea (guest) to form helical structure. Using steady-state and time-resolved spectroscopy, we observed the enhanced fluorescence quantum yield by ~1.8 to 2.4 times, enhanced anisotropy values and the disappearance of fast fluorescence decay component in the host-guest helical forms. In addition, the enhanced nonlinear optical responses of helical arrays infer the extended inter-porphyrin electronic coupling due to a significant change in dihedral angle between the neighboring porphyrin moieties. The current host-guest strategy will provide a guideline to improve the structural homogeneity of the photonic wire.

Function of Habitat Heterogeneity for the Biodiversity and Demography of Population in Small Mammal Community (소척추동물군집에서 개체군 변동과 생물다양성 유지를 위한 서식지 이질성의 기능)

  • Lee, Sang Don
    • The Korean Journal of Ecology
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    • v.18 no.4
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    • pp.512-523
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    • 1995
  • The central theme of Habital heterogeneity is to provide animals with habital complexity or structural diversity and to allow resource partitioning among individuals. In turn, the leads to population stability because prey can escape more easily with more hiding places causing less population fluctuation. Species diversity is characterized due to more potential niches both horizontally and verticall. Empirically, in homogeneous habitats population was less abundant, reproduction and survival were lower, spacing behavior, competition and dispersal were higher than in heterogeneous habitats. The results imply that diversity and conservation of species can be maintained through providing heterogeneous habitats.

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Cases of Tunnel Monitoring of Anisotropic/Heterogeneous Rock Masses (이방성/비균질 암반의 터널 계측 사례 분석)

  • Kim, Chang-Yong;Hong, Sung-Wan;Kim, Kwang-Yeom;Baek, Seung-Han
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.03a
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    • pp.1299-1306
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    • 2005
  • The introduction of geodetic methods of absolute displacement monitoring in tunnels has improved the value of the measurements significantly. By using this method, structurally controlled behavior and influences of an anisotropic rock mass can be determined and the excavation and support adjusted accordingly. In this study cases of tunnel monitoring in anisotropic/heterogeneous rock masses are analyzed, and various anisotrpic behavior of tunnel can be estimated. Because rock anisotropy and heterogeneity can have great influence on tunnel behavior, tunnel design considering rock anisotropy and heterogeneity is needed. Also under construction, feedback must be performed by using face mapping and monitoring to prevent over-deformation and tunnel collapse.

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