• Nuclear Engineering and Technology
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• v.38 no.3
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• pp.231-238
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• 2006

Whole-body exposure to high-dose radiation causes injury involving multiple organs that depends on their sensitivity to radiation. This acute radiation syndrome (ARS) is caused by a brief exposure of a major part of the body to radiation at a relatively high dose rate. ARS is characterized by an initial prodromal stage, a latent symptom-free period, a critical or manifestation phase that usually takes one of four forms (three forms): hematologic, gastrointestinal, or cardiovascular and neurological (neurovascular), depending upon the exposure dose, and a recovery phase or death. One of the most important factors in treating victims exposed to radiation is the estimation of the exposure dose. When high-dose exposure is considered, initial dose estimation must be performed in order to make strategy decisions for treatment as soon as possible. Dose estimation can be based on onset and severity of prodromal symptoms, decline in absolute lymphocyte count post exposure, and chromosomal analysis of peripheral blood lymphocytes. Moreover, dose assessment on the basis of calculation from reconstruction of the radiation event may be required. Experience of a criticality accident occurring in 1999 at Tokai-mura, Japan, showed that ARS led to multiple organ failure (MOF). This article will review ARS and discuss the possible mechanisms of MOF developing from ARS.

• Reproductive and Developmental Biology
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• v.30 no.4
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• pp.235-245
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• 2006

Di-n-butyl phthalate (DBP), diisononyl phthalate (DINP) and di-(2-ethylhexyl) adipate (DEHA) are ubiquitously distributed chemicals that are widely used as plasticizers and also found at low levels in foods. The aims of this study were to determine whether perinatal exposure to DBP, DINP and DEHA could alter normal patterns of neonatal development. Dams were provided with pulverized soy-free diet containing 20, 200, 2,000 and 10,000 ppm of DBP, 40, 400, 4.000 and 20,000 ppm of DINP, or 480, 2,400 and 12,000 ppm of DEHA from gestational day 15 to postnatal day 21. Exposure to the high doses of DBP, DINP and DEHA during gestational period significantly decreased food consumption and body weight gain of dams. These chemicals reduced neonatal body weight as well as that of the after maturation. Also, exposure to DINP of all the doses used and the higher doses (2,400 and 12,000 ppm) of DEHA decreased AGD at PND 1 in male neonates, though that to DBP did not affect AGD in males. In female neonates, an increase in AGD was observed in DBP- and DINP-exposed animals at the highest doses. Moreover, these chemicals affected survival rate of pups at PND 5, and delayed onset of eye opening in all chemica1-exposed groups at PND 17. These results suggest that perinatal exposure to these chemicals may affect the normal development and/or growth of offspring.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.4
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• pp.316-328
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• 2012

Objectives: This study was designed to provide the information regarding chemicals classification and health hazard by evaluating the toxicological effect through repeated inhalation exposure of methyl acrylate(MA) in Sprague-Dawley(SD) rat for 13 weeks. Methods: According to the notification with Ministry of Labor(No. 2009-68) and OECD Test Guideline 413, the rats were exposed to MA at concentration of 0, 56, 168, 280 ppm via whole body inhalation for 6 hours per day, 5 days per week, for 13 weeks. All animals were observed for mortality, morbidity and the change of body weight and food consumption were determined during the exposure period. Necropsy finding, organ weight, hematology, clinical biochemistry and histopathological examination following exposure were also performed. Results: There were no death and abnormal clinical signs relate to exposure MA. However, At 160 ppm and 280 ppm exposure groups, body weight and food consumption showed statistically significant decrease and histopathological changes in lung, trachea, nasal cavity, larynx were observed. Conclusions: MA was mainly affected respiratory tract. It is consequently provided to be classified as category 2(0.2 mg/L/6h < category 2 ${\leq}$ 1.0 mg/L/6h) for specific target organ toxicity following repeated exposure according to Standard for Classification and Labeling of Chemical Substance and Material Safety Data Sheet. The NOAEL(no observable adverse effect level) of MA was also determined to be lower than 56 ppm.

• Journal of the Korean Society of Radiology
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• v.14 no.7
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• pp.931-936
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• 2020

This study was conducted to observe the changes in radiation exposure dose and image quality of pediatric patients according to the presence and size of the gonadal shield when using the AEC system. X-ray equipment was used to measure the radiation exposure dose in the abdominal and gonads of the pediatric phantom when no shielding body was used and when three different sizes of shielding body were used, and SNR and CNR were measured through the obtained images. As a result of the study, the radiation exposure dose to the gonads decreased in proportion to the size of the radiation shield, but the radiation exposure dose to the abdomen was rather increased, and the image quality did not change. It is recommended to use a shield with a size optimized for the age, weight, and body size of the pediatric patient so as not to be overexposed by the increased radiation due to the radiation shield due to the use of the AEC System. For this purpose, information about the pediatric patient with the nurse It is believed that exchange is necessary.

• The Journal of Advanced Prosthodontics
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• v.15 no.5
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• pp.248-258
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• 2023

PURPOSE. This study aims to evaluate the effects of exposure energy on the lateral resolution and mechanical strength of dental zirconia manufactured using digital light processing (DLP). MATERIALS AND METHODS. A zirconia suspension and a custom top-down DLP printer were used for in-office manufacturing. The viscosity of the suspension and uniformity of the exposed light intensity were controlled. Based on the exposure energy dose delivered to each layer, the specimens were classified into three groups: low-energy (LE), medium-energy (ME), and high-energy (HE). For each energy group, a simplified molar cube was used to measure the widths of the outline (X_o and Y_o) and isthmus (X_i and Y_i), and a bar-shaped specimen of the sintered body was tested. A Kruskal-Wallis test for the lateral resolution and one-way analysis of variance for the mechanical strength were performed (α = .05). RESULTS. The zirconia green bodies of the ME group showed better lateral resolution than those of the LE and HE groups (both P < .001). Regarding the flexural strength of the sintered bodies, the ME group had the highest mean value, whereas the LE group had the lowest mean value (both P < .05). The ME group exhibited fewer agglomerates than the LE group, with no distinctive interlayer pores or surface defects. CONCLUSION. Based on these findings, the lateral resolution of the green body and flexural strength of the sintered body of dental zirconia could be affected by the exposure energy dose during DLP. The exposure energy should be optimized when fabricating DLP-based dental zirconia.

• Journal of radiological science and technology
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• v.40 no.1
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• pp.1-6
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• 2017

Visual evaluation of chest radiograph images is the most practical and effective method. This study compared the Body Mass Index, waist circumference, and mAs with chest radiographs of 351 women. The Bureau of Radiological Health method was used to evaluate the image quality of chest X-ray images by anatomical and physical methods. The average age of the subjects was $30.17{\pm}4.73$ and the average waist circumference was $66.91{\pm}4.67cm$. The mean Body Mass Index value was $20.21{\pm}2.23$, the mean value of mAs was $3.04{\pm}0.78$, and the mean value of Bureau of Radiological Health was $79.83{\pm}8.45$. When the Body Mass Index value increased, waist circumference and mAs mean value increased. The mean value of Body Mass Index was statistically significant(p<0.05) in Group 4 compared to Groups 1 and 2, with increasing Body Mass Index. Exposure control of the automatic exposure control system is considered to be well performed according to body thickness or Body Mass Index at the time of chest radiography. As the Body Mass Index increases, the thickness of the body increases and the breast thickness of the woman also increases. Therefore, it is considered that the exposure amount is changed by the automatic exposure control device to affect the image quality.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.15 no.12 s.105
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• pp.1327-1331
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• 2005

This Paper addresses what amount of whole-body vibration is exposed to Korean pilots of UH60 helicopters during their mission flight. To measure the expose4 whole-body vibration, the 12-axis whole-body vibration measurement system was used. It enables the direct measurement of whole-body vibration exposed from the body contact area consisting of the feet, hip and back. The measured 12-axis vibration signals were used to evaluate the vibration comfort level experienced by the pilots of UH60 helicopters. The evaluated vibration comfort level is found to be closeto 0.74-0.79m/s, which is equivalent to the semantic scale of 'fairly uncomfortable'. To assess the health effects of whole-body vibration exposed to Korean pilots of UH60 helicopters during their mission flight, the rms-based and VDV(vibration dose value)-based evaluation schemes, recommended by ISO 2631-1:1977, were exploited in this work. The evaluated results indicate that Korean pilots cannot avoid the fatigue-decreased proficiency limit after two-hour continuous flight. The whole-body vibration level exposed from the UH60 helicopters during continuous 10-hours mission flight is found to reach to the vibration exposure limit.

• The Research Journal of the Costume Culture
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• v.18 no.2
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• pp.229-244
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• 2010

This study aims to discuss the type and characteristics of primitivism in the modern fashion of the $21^{st}$ century and, as a research method, the concept of primitivism as well as the transition of the patterns of primitivism expressed in modern art have been considered and reviewed through a variety of references. In particular, an empirical analysis of the works that have been created from 2000 to 2009 has been performed using domestic and overseas fashion and collection magazines. The characteristics of primitivism in modern fashion possess the following types of expression: First, Sensuality can be cited as one of the characteristics, either by using direct or indirect exposure of the human body, a silhouette which fits tightly to the body, or creating the effect of sensual beauty using animal fur or bird feathers. Second, Incantation: Masks symbolizing primitive incantation are used to cover the human face or primitive incantation is incorporated as a theme of hair accessories or fashion trinkets, etc. In addition, such decorations as tattoos and the body colorations of ancient tribes are reproduced in modern fashion by means of body painting, printing or other accessories, emphasizing the image of occult primitiveness. Third, Naturalness can be cited as one of the characteristics. Naturalness is emphasized in modern fashion not through artificial decorations and processing, but rather through different patterns of exposure by which natural purity can be felt or through the use of non-artificial materials which recalls primitive civilization. Forth, Playfulness is expressed in the form of graffiti or abstract letters and paintings, and the character of the play is often expressed by the use of grotesque images based on various distortions and exaggerations of the human body, the utilization of symbols of primitive incantation and body and/or facial painting. Fifth, Lastly 'folkishness is emphasized. Folk-like objects, facial decorations, exposure of the body and intense color contrasts typically represent the folkish characteristics.

• Korean Journal of Environmental Biology
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• v.23 no.4
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• pp.357-361
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• 2005

The exposed strain of C. riparius treated with di (ethyl- hexyl)-phthalate (DEHP) did not result in a consistent relationship between mortality or sex ratio and chemical concentrations. And after treating with DEHP, the emergent female from the exposed strain appeared to be fatty with a large body volume comparing with the non - exposed strain. The emergent period (EP) was especially different between the exposed fourth strain and the non-exposed strain; generally the exposed strain was $7\~10$ days, and non - exposed strain was $17\~24$ days. Regarding sustainable exposed effects, the EP, the first emergent day (FED), and the body volume (BV) could be suggested as suitable bio - markers for detecting of exposure to various EDCs.

• Korean Journal of Environmental Biology
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• v.22 no.4
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• pp.532-536
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• 2004

Due to the fourth-instar larvae of C. riparius have a sensitive to ecdysteroidal molting hormones for the life cycle developments, accordingly the emerged adult affected corresponding to larval phase's environments. The emerged female from larval phase exposure to DEHP observed a fact body and clumsy fling behavior in females. The body volume of treated female groups was clearly larger than that of control fe- males. In the 2D/E gel 1108 protein spots were identified. The visualized protein spots allowed extraction of 27 protein spots differed more than 3 fold in DEHP treated animals, which was approximately 2.4％ of the total protein spots. In this view, the body volume (or morphological characters) was well observed and detected faster than physiological detection for various EDCs. In this study, the body volume as a detecting po-int for EDCs suggested a bio-marker in individual levels.