• Nuclear Engineering and Technology
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• v.55 no.4
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• pp.1476-1484
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• 2023

Laboratory experiments and point monitoring of reservoir sediments have proven that stable sulfate reduction (SSR) can lower the concentrations of toxic metals and sulfate in acidic groundwater for a long time. Here, we hypothesize that SSR occurred during in situ leaching after uranium mining, which can impact the fate of acid groundwater in an entire region. To test this, we applied a sulfur isotope fractionation method to analyze the mechanism for natural attenuation of contaminated groundwater produced by acid in situ leaching of uranium (Xinjiang, China). The results showed that δ³⁴S increased over time after the cessation of uranium mining, and natural attenuation caused considerable, area-scale immobilization of sulfur corresponding to retention levels of 5.3%-48.3% while simultaneously decreasing the concentration of uranium. Isotopic evidence for SSR in the area, together with evidence for changes of pollutant concentrations, suggest that area-scale SSR is most likely also important at other acid mining sites for uranium, where retention of acid groundwater may be strengthened through natural attenuation. To recapitulate, the sulfur isotope fractionation method constitutes a relatively accurate tool for quantification of spatiotemporal trends for groundwater during migration and transformation resulting from acid in situ leaching of uranium in northern China.

• Journal of Korean society of Dental Hygiene
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• v.10 no.4
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• pp.717-725
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• 2010

Objectives : This study was to determine the level of occupational exposure and quality of life and to investigate the effect of variables related occupational exposure on quality of life in dental hygienists. Methods : A survey questionnaire was mailed to dental hygienists from April 4 to May 15, 2010. The subjects were 256(56.9%), who were worked in dental hospital and clinic with mean age of $29.59{\pm}7.30$. Quality of life was measured using the WHOQOL-BREF. It consists of 26 items, each with 5-point likert scale. Self control of occupational exposure was measured using the 3-items. The data were analyzed with chi-square, t-test, one-way ANOVA, pearson correlation coefficients and multiple regression using the SPSS WIN 17.0 program. Results : Regarding quality of life, the subjects was a mean of 90.73 out of a maximum 130 points. The level of self control occupational exposure a mean of 3.20 out of a maximum 5 points. Self control of occupational exposure, frequency of panorama radiography, work experience of radiography had a significant impact on quality of life in dental hygienists. Conclusions : Based on the findings, occupational exposure is negatively associated with quality of life in dental hygienists. These results suggest that health promotion program should be considered various factors related occupational exposure in dental hygienists.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.38 no.2
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• pp.101-109
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• 2012

Objectives: The inactivation of the tumor suppressor gene $p16^{INK4a}$ plays an important role in the development of malignant tumors, including oral squamous cell carcinoma. The p16 gene is involved in the p16/cyclin-dependent kinase/retinoblastoma (Rb) gene pathway of cell cycle control. The p16 protein is considered a negative regulator of this pathway. The p16 gene encodes an inhibitor of cyclin-dependent kinases 4 and 6 which regulate the phosphorylation of the retinoblastoma gene and G1 to S phase transition in the cell cycle. However, the p16 gene can lose its functionality through point mutations, loss of heterozygosity or methylation of its promoter region. Materials and Methods: In this study, the authors analyzed the correlation between various clinicopathological findings- patient age, gender and smoking, disease recurrence, tumor size, stage, and differentiation- and p16 protein expression or p16 promoter hypermethylation in 59 cases of head and neck squamous cell carcinoma. Results: The results revealed p16 protein expression and p16 promoter hypermethylation in 28 cases (47.5%) and 21 cases (35.6%), respectively, of head and neck squamous cell carcinoma. However, neither p16 protein expression nor p16 promoter hypermethylation had any statistical influence on clinicopathological findings or survival rate. Conclusion: This data, and a review of the literature, suggest that p16 promoter hypermethylation cannot yet be used as an independent prognostic factor influencing carcinogenesis, but must be considered as an important factor along with other genetic alterations affecting the pRb pathway.

• 한국균학회소식:학술대회논문집
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• 2018.05a
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• pp.41-41
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• 2018

There has been an impetus in the development of biocontrol agents (BCAs) with the removal of a number of chemical compounds in the market, especially in the European Union. This has been a major driver in the development of Integrated Pest Management systems (IPM) for both pest and disease control. For control of mycotoxigenic fungi, there is interest in both control of colonization and more importantly toxin contamination of staple food commodities. Thus the relative inoculum potential of biocontrol agent vs the toxigenic specie sis important. The major bottlenecks in the production and development of formulations of biocontrol agents are the resilience of the strains, inoculum quality and formulation with effective field efficacy. It was recently been shown for mycotoxigenic fungi such as Aspergillus flavus, under extreme climate change conditions, growth is not affected although there may be a stimulation of aflatoxin production. Thus, the development of resilient biocontrol strains which can may have conserved control efficacy but have the necessary resilience becomes critical form a food security point of view. Indeed, under predicted climate change scenarios the diversity of pests and fungal diseases are expected to have profound impacts on food security. Thus, when examining the identification of potential biocontrol strains, production and formulation it is critical that the resilience to CC environmental factors are included and quantified. The problems in relation to the physiological competence and the relative humidity range over which efficacy can occur, especially pre-harvest may be increase under climate change conditions. We have examined the efficacy of atoxigenic strains of A. flavus and Clanostachys rosea and other candidates for control of A. flavus and aflatoxin contamination of maize, and for Fusarium verticillioides and fumonisin toxin control. We have also examined the potential use of fluidized-bed drying, nanoparticles/nanospheres and encapsulation approaches to enhance the potential for the production of resilient biocontrol formulations. The objective being the delivery of biocontrol efficacy under extreme interacting climatic conditions. The potential impact of climate change factors on the efficacy of biocontrol of fungal diseases and mycotoxins are discussed.

• Geomechanics and Engineering
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• v.36 no.1
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• pp.39-50
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• 2024

Bitumen and high-quality subangular aggregates, the two principal materials used for asphalt concrete construction, are finite and expensive materials. The general availability of crumb rubber and naturally occurring aggregates of different shapes, especially flat and elongated shapes, indicates that they are feasible alternative materials for expanding the volume of bitumen and utilizing a wider range of aggregate shapes for the development of asphalt concrete, with an associated environmental benefit. The study investigated the effect of adding up to 15% crumb rubber and aggregates sorted into different groups, i.e., rounded, elongated, flat, and their combinations, on the rheological and mechanical properties and durability of 50/70 of hot-mix asphalt pavement. The addition of crumb rubber decreased ductility and penetration but increased the softening point. For a 5.5% bitumen content, asphalt concrete briquettes consisting of 7% crumb rubber and three types of aggregate shapes, i.e., 100% rounded, a mix of 75% rounded and 25% elongated, and a mix of 75% rounded, 15% elongated and 10% flat, were associated with high Marshall stability and indirect tensile strength as well as low lateral deformation due to their high solidity and moderate angularity ratio. Also, the addition of 7% crumb rubber resulted in a significant improvement in the tensile strength ratio and rebound strain of briquettes consisting of 75% rounded and 25% elongated aggregates and those with 75% rounded, 15% elongated and 10% flat aggregates. In relation to the parameters investigated, the three groups of briquettes met some of the local (South Africa) requirements for the surface course and base course of low traffic volume roads.

• Health Policy and Management
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• v.7 no.1
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• pp.155-182
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• 1997

Objectives : This study was designed to compare North Korea and South Korea in measures of the quality of life (physical quality of life index and human development index) and to investigate the impact of selected medical and socioeconomic factors on PQL variables. Data and Methods : The World Bank, the United Nations Development Programme, and Population Reference Bureau were the principal sources of statistical data of 121 countries. Variables included infant mortality, life expectancy at birth, literacy rate, secondary school enrollment (male and female), GNP per capita, population per doctor, daily calorie supply per capita, and a composite PQL index. The Ordinary Least Square model was employed for cross-countries analysis. Findings : Both countries under quite different political and economic systems saw big improvememts in the quality of life, reducing mortality and prolonging life expectancy during the past three decades. In recent decad, however, North Korea has experienced abrupt exacerbation in the quality of life. Significant improvements in infant mortality of the population wer attributable mainly to GNP per capita and the secondary school enrollemt of female. The principal predictors of life expectancy at birth were population per doctor, infant mortality, and literacy rate. The secondary school enrollment of female and population per doctor were significantly associated with improvements in the physical quality of life index (PQLI). Conclusion : The results of this study confirmed a point illustrated by other studies : The association between quality of life as a measure of health status and socioeconomic factors was strong and positive. The important contribution of educational attainment in general, female education level in particular to improvements in the quality of life deserves good news for building an integrated health care system in the reunified Korea, taking into account the high level of education two koreas are enjoying. Meanwhile, when a sharp drop in the quality of life has been observed in North Korea under serious economic difficulties and food shortage in recent decade, the significant contribution of economic development to improvements in the quality of life poses bad nows for reunifying Korean health care in economic terms.

• Geomechanics and Engineering
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• v.36 no.5
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• pp.465-474
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• 2024

Uniaxial compressive strength (UCS) is a critical geomechanical parameter that plays a significant role in the evaluation of rocks. The practice of indirectly estimating said characteristics is widespread due to the challenges associated with obtaining high-quality core samples. The primary aim of this study is to investigate the feasibility of utilizing the gene expression programming (GEP) technique for the purpose of forecasting the UCS for various rock categories, including Schist, Granite, Claystone, Travertine, Sandstone, Slate, Limestone, Marl, and Dolomite, which were sourced from a wide range of quarry sites. The present study utilized a total of 170 datasets, comprising Schmidt hammer (SH), porosity (n), point load index (Is(50)), and P-wave velocity (Vp), as the effective parameters in the model to determine their impact on the UCS. The UCS parameter was computed through the utilization of the GEP model, resulting in the generation of an equation. Subsequently, the efficacy of the GEP model and the resultant equation were assessed using various statistical evaluation metrics to determine their predictive capabilities. The outcomes indicate the prospective capacity of the GEP model and the resultant equation in forecasting the unconfined compressive strength (UCS). The significance of this study lies in its ability to enable geotechnical engineers to make estimations of the UCS of rocks, without the requirement of conducting expensive and time-consuming experimental tests. In particular, a user-friendly program was developed based on the GEP model to enable rapid and very accurate calculation of rock's UCS, doing away with the necessity for costly and time-consuming laboratory experiments.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.16
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• pp.7189-7193
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• 2015

Background: Cancer is a leading cause of death throughout the world. Increasing life expectancy and aging population are important factors for increasing cancer incidences in developing countries. National programs are essential for prevention and control of cancer in any society. This study aimed to investigate cancer epidemiology and trends in the province of Hamadan, located in Northwest Iran. Materials and Methods: This analytical study was carried out based on cancer registry data from 2004 to 2009 in the province of Hamadan, analyzed using STATA (version 12) software for descriptive tests and Join point 4.1.1.1 software for analytical tests. Results: There were 7,767 registered cases of cancer during the 6 years studied. Of the total cases registered, 59.1% (4,592 cases) involved men and 40.9% (3,175 cases) occurred in women. Age-standardized incidence rates (ASR) increased from 72.9 to 132.0 in males and 48.2 to 115.0 in females during the 6 years of the study (p<0.001). The most common cancers were skin, stomach, breast, bladder, and leukemia. In women, teh most common were breast, skin, stomach, colorectal, and leukemia, in that order, and in men skin, stomach, bladder, leukemia, and prostate cancers. Conclusions: The cancer incidence is greater in men that women in this region but with increasing trends in both sexes. Planning regarding education in prevention of exposure to risk factors and control strategies is required to decrease the incident cases. Screening programs for common cancers in older age groups might be helpful to reduce the disease impact.

• Korean Institute of Interior Design Journal
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• v.21 no.2
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• pp.23-34
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• 2012

After the modern age, the rapid urbanizationhad a big impact on the then architecture. R. Venturi and A. Rossi are two of the leading architects, developing architecture in cities in the US and Europe respectively. This study shed light on a tangible and intangible meaning and interpretation of urban landscapes through their architectural thoughts and architectures. The followings are the physical and intangible meaning and interpretation in architectural thoughts and works of those two architects. Venturi understood that iconological landscapes at the roadside in large citiesare the nature of physical landscapes. To Venturi, the façades of buildings at the roadside are a part of signage such as traffic lights and road signs, and those façades have the meaning of symbolic systems beyond simple physical landscapes. To A. Rossi, types of buildings as physical townscapes are a key role supporting raw data of classification in architecture. And also, those types have significance of the basic data shedding light on the principles and history of cities. For intangible factors in R. Venturi's architecture, daily routine, function and use, time, a use for a building and others form complex architecture. And also, those factors describe shared values of the same period as the façades of buildings and complex symbols and formative lexicons in metaphorical terms. For A. Rossi's intangible factors, 'collective memory' is buried in inhabitants of the city, and with that, the city is a place for memory to its inhabitants. What is more, cities' monuments have intangible landscapes like 'sustainability', 'permanence' and so on. With lots of events happening throughoutcities, those monuments are the whole images of cities giving the value to the urban buildings that reside in cities. Finally, R. Venturi's all-encompassing complex architecture concept was extended on a tangible and intangible point of townscapes. It was found that A. Rossi's tangible thought was formed from the whole landscape of historic cities in then Italy as the background of time and place. Also, With types of urban buildings and 'collective memory', A. Rossi drew architectural norms and formats of unchangeable types.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.06a
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• pp.56-66
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• 2005

In response to the increasing emphasis being placed on the importance of international cooperation as part of global efforts to cope with growing non proliferation, and security, concerns in the nuclear field, the Director General of the International Atomic Energy Agency (IAEA), Mohamed ElBaradei, appointed an international group of experts to consider possible multilateral approaches to the nuclear fuel cycle. The mandate of the Expert Group was three fold: ${\bullet}$ To identify and provide an analysis of issues and options relevant to multilateral approaches to the front and back ends of the nuclear fuel cycle; ${\bullet}$ To provide an overview of the policy, legal, security, economic, institutional and technological incentives and disincentives for cooperation in multilateral arrangements for the front and back ends of the nuclear fuel cycle; and ${\bullet}$ To provide a brief review of the historical and current experiences and analyses relating to multilateral fuel cycle arrangements relevant to the work of the Expert Group. The overall purpose was to assess MNAs in the framework of a double objective: strengthening the international nuclear non proliferation regime and making the peaceful uses of nuclear energy more economical and attractive. The Group identifies options for MNAs - options in terms of policy, institutional and legal factors - for those parts of the nuclear fuel cycle of greatest sensitivity from the point of view of proliferation risk. It also reflects the Groups deliberations on the corresponding benefits and disadvantages (pros and cons) of the various options and approaches. Although the Expert Group was able to agree to forward the resulting report to the Director General, it is important to note that the report does not reflect agreement by all of the experts on any of the options, nor a consensus assessment of their respective value. It is intended only to present options for MNAs, and to reflect on the range of considerations which could impact on the desirability and feasibility of those options.