• Advances in Computational Design
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• v.2 no.2
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• pp.147-168
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• 2017

Over the past couple decades, externally bonded fiber reinforced polymer (FRP) composites have emerged as a repair and strengthening material for many concrete infrastructure applications. This paper presents an analytical investigation of the use of carbon FRP (CFRP) for a specific problem that occurs in concrete bridge girders wherein the girder ends are damaged by excessive exposure to deicing salts and numerous freezing/thawing cycles. A 3D finite element (FE) model of a full scale prestressed concrete (PC) I-girder is used to investigate the effect of damage to the cover concrete and stirrups in the end region of the girder. Parametric studies are performed using externally bonded CFRP shear laminates to determine the most effective repair schemes for the damaged end region under a short shear span-to-depth ratio. Experimental results on shear pull off tests of CFRP laminates that have undergone accelerated aging are used to calibrate a bond stress-slip model for the interface between the FRP and concrete substrate and approximate the reduced bond stress-slip properties associated with exposure to the environment that causes this type of end region damage. The results of these analyses indicate that this particular application of this material can be effective in recovering the original strength of PC bridge girders with damaged end regions, even after environmental aging.

• Journal of Environmental Health Sciences
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• v.36 no.2
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• pp.163-169
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• 2010

All forms of asbestos are proven human carcinogens. All forms of asbestos cause malignant mesothelioma, lung, laryngeal, and ovarian cancers, and may cause gastrointestinal and other cancers. No exposure to asbestos is without risk, and there is no safe threshold of exposure to asbestos. Asbestos cancer victims die painful lingering deaths. These deaths are almost entirely preventable. When evidence of the carcinogenicity of asbestos became incontrovertible, concerned parties, including the Collegium Ramazzini, called for a universal ban on the mining, manufacture and use of asbestos in all countries around the world. Asbestos is now banned in 52 countries, and safer products have replaced many materials that once were made with asbestos. Nonetheless, a large number of countries still use, import, and export asbestos and asbestos-containing products. And still today in many countries that have banned other forms of asbestos, the so-called "controlled use" of chrysotile asbestos continues to be permitted, an exemption that has no basis in medical science but rather reflects the political and economic influence of the asbestos mining and manufacturing industry. To protect the health of all people in the world, industrial workers, construction workers, women and children, now and in future generations - the Collegium Ramazzini calls again today on all countries of the world, as we have repeatedly in the past, to join in the international endeavor to ban all forms of asbestos. An international ban on asbestos is urgently needed.

• Journal of Environmental Health Sciences
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• v.36 no.6
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• pp.518-526
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• 2010

There are millions of deaths from cancer worldwide every year. Among them, 4~10% are considered to be attributable to occupational factors and 0.6 million workers die annually from work-related cancers. Occupational cancers are relatively preventable compared with the cancers associated with other factors. In the developed countries, especially in Europe, there have been hundreds of occupational cancers reported annually in the respective nation-states. However, there were only 35 cases reported in Korea in the 1990s which were accepted as being work-related cancers. This difference might be related to a low level of recognition, detection, and acceptance of occupational cancer and carcinogens in Korea. To prevent the risk of exposure to carcinogens a comprehensive list of carcinogens must be prepared. This should be followed by timely dissemination of information which will enable fundamental controls to be implemented, such as the imposition of ban, substitution, and engineering controls. This will require setting up procedures to record the past use and exposure data and carrying out robust statistical analyses of that data on occupational cancers and carcinogens.

• Communications for Statistical Applications and Methods
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• v.23 no.1
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• pp.1-20
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• 2016

Causal inference methodologies have been developed for the past decade to estimate the unconfounded effect of an exposure under several key assumptions. These assumptions include, but are not limited to, the stable unit treatment value assumption, the strong ignorability of treatment assignment assumption, and the assumption that propensity scores be bounded away from zero and one (the positivity assumption). Of these assumptions, the first two have received much attention in the literature. Yet the positivity assumption has been recently discussed in only a few papers. Propensity scores of zero or one are indicative of deterministic exposure so that causal effects cannot be defined for these subjects. Therefore, these subjects need to be removed because no comparable comparison groups can be found for such subjects. In this paper, using currently available causal inference methods, we evaluate the effect of arbitrary cutoffs in the distribution of propensity scores and the impact of those decisions on bias and efficiency. We propose a tree-based method that performs well in terms of bias reduction when the definition of positivity is based on a single confounder. This tree-based method can be easily implemented using the statistical software program, R. R code for the studies is available online.

• The Research Journal of the Costume Culture
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• v.13 no.3 s.56
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• pp.425-438
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• 2005

This study is to examine the types of expression and aesthetic characteristics of on-line game characters by analyzing those game characters' body and their costume that appear in various domestic on-line game sites. It is shown in this study that types of the human bodies and costume expressed through the game characters are grouped into five categories such as exposure and tightness, enlargement and exaggeration, curtailment and simplification, gender stereotype and unification. Furthermore, there are four typical aesthetic characteristics resulting from those types of expressions; First, 'grotesque' is expressed in the form of extreme enlargement and exaggeration, extreme exposure and concealment, combined images among human, animal or machine, or monstrous devilish images. Second, in an effort to express 'eroticism', bodies are directly exposed, see-through costumes are used in order to emphasize the body lines or very tight designs are used. Third, 'futuristic' characteristics are shown through geometrical shape and silhouette, machine-like details, strong artificial colors or glossy hi-tech material. Lastly, 'pastiche' is expressed with reconciliation of variety of costumes of game characters. Various opposite or heterogeneous styles are combined or harmonized each other to show pastiche, of which examples are male and female, superior culture and inferior one, rich and poor, oriental and western, human and machine, human and nature or past and future, etc.

• Journal of Korean Academy of Nursing
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• v.44 no.2
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• pp.159-169
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• 2014

Purpose: The purpose of this study was to test and validate a model to predict contraception behavior in unmarried men and women. Methods: Data were collected from a questionnaire survey of 180 unmarried men and 186 unmarried women 20 years of age or over who had sexual relationships in the past 6 months. Participants were from Seoul, Kyunggi, Daegu, and Busan and data collection was done from February 19 to April 16, 2013. Results: Model fit indices for the hypotheoretical model fitted to the recommended levels. Out of 15 paths, 11 were statistically significant in both. Predictors of contraception behavior in unmarried men and women were intention to use contraception and self-efficacy for contraception. Exposure to sexual content was directly significant to the intention in men only. Self-efficacy for contraception was affected by perceived threat of pregnancy and gender role attitude. In women, the two predictors were also significant except for the effect of exposure to sexual contents. Conclusion: Results indicate that an intervention program which increases self-efficacy in unmarried men and women contributes to effective contraception behavior. In addition, proper sexual education programs using positive aspect of mass media can help develop active participation for contraception behavior.

• Archives of Plastic Surgery
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• v.43 no.4
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• pp.311-315
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• 2016

In Korea, lateral canthoplasty, along with medial epicanthoplasty, has become popular over the past years to widen the horizontal length of the palpebral fissure. However, the effect of the surgery differs greatly depending on the shape and structure of the eyes. If over-widened, complications such as eversion, scarring, and conjunctival exposure may occur. Thus, the author of this study suggests a more effective and safe method for lateral canthal lengthening that causes minimal complications. A total of 236 patients underwent lateral canthoplasty between July 2007 and December 2015. For each patient, a triangular flap 4-5 mm away from the lateral canthus was elevated and rotated 45 degrees laterally while the continuity of the lower eyelid gray line was maintained. A new lateral canthus was created by fixating the rotation flap to the lateral orbital rim with minimal skin trimming and tension-free sutures, preventing relapse and maintaining a triangular shape. In more than 95% of cases, effective and satisfactory extension was achieved. On average, a 3 mm extension of the lateral canthus was achieved. There were minor complications such as wound dehiscence, webbing, and scarring, which were easily corrected. The author not only extended the lateral canthus 3-4 mm laterally but also maintained the continuity of the gray line on the lower lid as a more natural-looking triangular shape, while minimizing complications such as webbing and conjunctival exposure.

• Journal of the Korean Medical Association
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• v.61 no.11
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• pp.655-661
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• 2018

Incidence of basal and squamous cell carcinoma is increasing among Korean. With increasing this incidence we need to attend the management and prevention of these cutaneous malignancies. Basal cell carcinoma (BCC) is the most common skin malignancy. Sun exposure is the most important environmental cause of BCC. Daily sun protection especially avoiding sun exposure between 10 a.m. and 4 p.m. provides most effective prevention against chronic ultraviolet-induced skin damage. Hedgehog pathway inhibitors are used locally advanced and metastatic BCC lesions in Korea. Until recently, there are no reports whether it developed resistance of Hedgehog pathway inhibitors with advanced BCC in Korean patients. Among malignant skin tumors, 19.1% were squamous cell carcinoma (SCC). The incidence of SCC was rapidly increased over the past years. However, the incidence rate of SCC in Japan has not been changed from the period 1976-1980 to 1986-1990. Sentinel lymph node biopsy for SCC did not provide diagnostic value. Bowen's disease and Erythroplasia of Queyrat are considered as carcinoma in situ of the skin. Erythroplasia of Queyrat have worse prognosis with a higher rate of malignant degeneration. Dermoscopy may helpful tool in assisting the noninvasive diagnosis of carcinoma in situ of the skin.

• Journal of Radiation Protection and Research
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• v.49 no.1
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• pp.1-18
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• 2024

Exponential growth has been observed in nuclear medicine procedures worldwide in the past decades. The considerable increase is attributed to the advance of positron emission tomography and single photon emission computed tomography, as well as the introduction of new radiopharmaceuticals. Although nuclear medicine procedures provide undisputable diagnostic and therapeutic benefits to patients, the substantial increase in radiation exposure to nuclear medicine patients raises concerns about potential adverse health effects and calls for the urgent need to monitor exposure levels. In the current article, model-based internal dosimetry methods were reviewed, focusing on Medical Internal Radiation Dose (MIRD) formalism, biokinetic data, human anatomy models (stylized, voxel, and hybrid computational human phantoms), and energy spectrum data of radionuclides. Key results from many articles on nuclear medicine dosimetry and comparisons of dosimetry quantities based on different types of human anatomy models were summarized. Key characteristics of seven model-based dose calculation tools were tabulated and discussed, including dose quantities, computational human phantoms used for dose calculations, decay data for radionuclides, biokinetic data, and user interface. Lastly, future research needs in nuclear medicine dosimetry were discussed. Model-based internal dosimetry methods were reviewed focusing on MIRD formalism, biokinetic data, human anatomy models, and energy spectrum data of radionuclides. Future research should focus on updating biokinetic data, revising energy transfer quantities for alimentary and gastrointestinal tracts, accounting for body size in nuclear medicine dosimetry, and recalculating dose coefficients based on the latest biokinetic and energy transfer data.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.sup1
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• pp.49-53
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• 2016

Evidence shows that tobacco advertising and promotion activities may increase tobacco consumption and usage, especially in youth. Despite the regulation on prohibiting advertisement of any tobacco product, tobacco advertisement and promotion activities are still common in Vietnam. This article presents current exposure to tobacco advertising and promotion (TAP) among school children aged 13 to 15 years in Vietnam in 2014 and potential influencing factors. Data from the Global Youth Tobacco Survey 2014 in Vietnam covering 3,430 school aged children were used. Both descriptive and analytical statistics were carried out with Stata 13 statistical software. Binary logistic regression was applied to explain the exposure to TAP among youth and examine relationships with individual factors. A significance level of p<0.05 and sampling weights were used in all of the computations. In the past 30 days, 48.6% of the students experienced exposure to at least 1 type of tobacco advertising or promotion. Wearing or otherwise using products related to tobacco was the most exposure TAP type reported by students (22.3%). The internet (22.1), points of sales (19.2) and social events (11.5) were three places that students aged 13-15 frequently were exposed to TAP. Binary logistic results showed that gender (female vs male) (OR = 0.61, 95%CI: 0.52 - 0.71), susceptibility to smoking (OR = 2.12, 95%CI: 1.53 - 2.92), closest friends' smoked (OR = 1.43, 95%CI: 1.2 - 1.7) and parents smoking status (OR = 2.83, 95%CI: 1.6 - 5.01) were significantly associated with TAP exposure among school-aged children. The research findings should contribute to effective implementation of measures for preventing and controlling tobacco use among students aged 13-15 in Viet Nam.