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Growth Pattern of Red-tongued Viper Snake (Gloydius ussuriensis) Inhabiting Gapado, Jeju Island (가파도에 서식하는 쇠살모사의 성장 패턴)

  • Kim, Byoung Soo;Chang, Min-Ho;Oh, Hong Shik
    • Journal of Environmental Impact Assessment
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    • 제25권6호
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    • pp.477-486
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    • 2016
  • We investigated the growth pattern of Red-tongued viper snakes (Gloydius ussuriensis), which were captured from the islet of the Jeju Island, Gapado between April, 2006 and November, 2009. The results indicated that there were some snakes that grew relatively fast, but most snakes either almost did not grow or grew around 10mm in snout-vent length during one year period. High growth rates was April and June. Since the growth rate of snakes is highly correlated with their foods, these results implied that the feeding activity of Red-tongued viper snakes is high during this period compared to other months. In female, difference in body condition between good-conditioned and bad-conditioned snakes became large as time elapsed from April to June. The body condition of the male Red-tongued viper snakes improved with the progression of time from April till June. Many of the Red-tongued viper snakes were captured between April and June, while they were rarely captured between July and September. Some of the Red-tongued viper snakes were captured during the autumn season. This tendency was because snakes were rarely active during hibernation and peak summer seasons. Thus, Red-tongued viper snakes are active between April and June and between September and November. They then go into hibernation as the temperature dropped in November. Furthermore, the limitation of the movement period of the Red-tongued viper snakes restricted their feeding activities while foods became scarce, which ultimately restricted their overall growth rate. The growth rate of the snakes decreased with age. The snout-vent length of the Red-tongued viper snakes and growth rate showed a negative correlation (r = -0.591), however, it was not statistically significant due to small sample size. The findings from this study could provide meaningful information in the further study of the life cycle of Red-tongued viper snakes.

Evaluation of Scattered Dose to the Contralateral Breast by Separating Effect of Medial Tangential Field and Lateral Tangential Field: A Comparison of Common Primary Breast Irradiation Techniques (유방암 접선조사 치료 방법에 대한 반대쪽 유방에서의 산란선량 평가)

  • Ban, Tae-Joon;Jeon, Soo-Dong;Kwak, Jung-Won;Baek, Geum-Mun
    • The Journal of Korean Society for Radiation Therapy
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    • 제24권2호
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    • pp.183-188
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    • 2012
  • Purpose: The concern of improving the quality of life and reducing side effects related to cancer treatment has been a subject of interest in recent years with advances in cancer treatment techniques and increasing survival time. This study is an analysis of differing scattered dose to the contralateral breast using common different treatment techniques. Materials and Methods: Eclipse 10.0 (Varian, USA) based $30^{\circ}$ EDW (Enhanced dynamic wedge) plan, $15^{\circ}$ wedge plan, $30^{\circ}$ wedge plan, Open beam plan, FiF (field in field) plan were established using CT image of breast phantom which in our hospital. Each treatment plan were designed to exposure 400 cGy using CL-6EX (VARIAN, USA) and we measured scattered dose at 1 cm, 3 cm, 5 cm, 9 cm away from medial side of the phantom at 1 cm depth using ionization chamber (FC 65G, IBA). We carried out measurement by separating effect of medial tangential field and lateral tangential field and analyze. Results: The evaluation of scattered dose to contralateral breast, $30^{\circ}$ EDW plan, $15^{\circ}$ wedge plan, $30^{\circ}$ wedge plan, Open beam plan, FIF plan showed 6.55%, 4.72%, 2.79%, 2.33%, 1.87% about prescription dose of each treatment plan. The result of scattered dose measurement by separating effect of medial tangential field and lateral tangential field results were 4.94%, 3.33%, 1.55%, 1.17%, 0.77% about prescription dose at medial tangential field and 1.61%, 1.40%, 1.24%, 1.16%, 1.10% at lateral tangential field along with measured distance. Conclusion: In our experiment, FiF treatment technique generates minimum of scattered dose to contralateral breast which come from mainly phantom scatter factor. Whereas $30^{\circ}$ wedge plan generates maximum of scattered doses to contralateral breast and 3.3% of them was scattered from gantry head. The description of treatment planning system showed a loss of precision for a relatively low scatter dose region. Scattered dose out of Treatment radiation field is relatively lower than prescription dose but, in decision of radiation therapy, it cannot be ignored that doses to contralateral breast are related with probability of secondary cancer.

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Evaluation on the Radiation Exposure of Radiation Workers in Proton Therapy (양성자 치료 시 방사선 작업 종사자에게 미치는 방사선 피폭에 대한 평가)

  • Lee, Seung-Hyun;Jang, Yo-Jong;Kim, Tae-Yoon;Jeong, Do-Hyung;Choi, Gye-Suk
    • The Journal of Korean Society for Radiation Therapy
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    • 제24권2호
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    • pp.107-114
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    • 2012
  • Purpose: Unlike the existing linear accelerator with photon, proton therapy produces a number of second radiation due to the kinds of nuclide including neutron that is produced from the interaction with matter, and more attention must be paid on the exposure level of radiation workers for this reason. Therefore, thermoluminescence dosimeter (TLD) that is being widely used to measure radiation was utilized to analyze the exposure level of the radiation workers and propose a basic data about the radiation exposure level during the proton therapy. Materials and Methods: The subjects were radiation workers who worked at the proton therapy center of National Cancer Center and TLD Badge was used to compare the measured data of exposure level. In order to check the dispersion of exposure dose on body parts from the second radiation coming out surrounding the beam line of proton, TLD (width and length: 3 mm each) was attached to on the body spots (lateral canthi, neck, nipples, umbilicus, back, wrists) and retained them for 8 working hours, and the average data was obtained after measuring them for 80 hours. Moreover, in order to look into the dispersion of spatial exposure in the treatment room, TLD was attached on the snout, PPS (Patient Positioning System), Pendant, block closet, DIPS (Digital Image Positioning System), Console, doors and measured its exposure dose level during the working hours per day. Results: As a result of measuring exposure level of TLD Badge of radiation workers, quarterly average was 0.174 mSv, yearly average was 0.543 mSv, and after measuring the exposure level of body spots, it showed that the highest exposed body spot was neck and the lowest exposed body spot was back (the middle point of a line connecting both scapula superior angles). Investigation into the spatial exposure according to the workers' movement revealed that the exposure level was highest near the snout and as the distance becomes distant, it went lower. Conclusion: Even a small amount of exposure will eventually increase cumulative dose and exposure dose on a specific body part can bring health risks if one works in a same location for a long period. Therefore, radiation workers must thoroughly manage exposure dose and try their best to minimize it according to ALARA (As Low As Reasonably Achievable) as the International Commission on Radiological Protection (ICRP) recommends.

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Attitudes to Safety of Genetically Modified Foods in Korea -Focus on Consumers- (유전자재조합 식품의 안전성에 대한 기본인식 조사 -일반 소비자를 중심으로 _)

  • 김영찬;박경진;김성조;강은영;김동연
    • Journal of Food Hygiene and Safety
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    • 제16권1호
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    • pp.66-75
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    • 2001
  • A survey was conducted to investigate consumers'attitudes toward the foods developed by gene recombination techniques from December, 1999 to April, 2000. The questionnaires were mailed to 1,500 people, and the 1,101 people responded. The consumers were asked about knowledge, acceptance, intention of purchasing, and labeling information. Although the portion of the consumers (88.8%) knowing the genetically modified floods (GMF) was lower than that of the flood expert group (98.7%), many consumers had some knowledge on the GMF, which may be influenced by news released from mass media. Seventy-nine percent of the consumers responded that gene recombination technology is necessary in food production, which is similar to the findings on the survey of the expert group. The portion of the consumers responding that these foods are potentially hazard was 88.1%, which is a little higher than the data (80.9%) from the expert group. The consumers having greater knowledge less worried about a potential hazard of the gene recombinant foods (p<0.01). Although 62.9% of the consumers responded to be willing to purchase those foods, only 16.2% of them responded to purchase the foods with no conditions, which is lower to that from the expert group (23.5%). There was no statistically significant relationship between the knowledge and the intention of purchasing. The ninety point three percent of the consumers wanted the information on gene recombination to be labeled on the foods. The data from this survey suggest that knowledge of the consumers on the GMF are not accurate, so proper strategy for consumer education may need to be developed. In addition, it is necessary to improve safety assessment system and analytical techniques for genetically modified foods (GMF) and to build pre- and post-market surveillance system fur efficient implementation of the GMF labeling.

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Inhibitory Effects on the Enzymes Involved in the Inflammation by the Ethanol Extracts of Plant Foodstuffs (식물성 일반식품 자원의 에탄올 추출물이 염증 효소계에 미치는 영향)

  • Kwon, Eun-Sook;Kim, Il-Rang;Kwon, Hoon-Jeong
    • Korean Journal of Food Science and Technology
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    • 제39권3호
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    • pp.348-352
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    • 2007
  • Inflammation is a complex process resulting from a variety of mechanisms. Combined inhibition of the activities of enzymes involved in the process may therefore be considered more important in anti-inflammatory property of plant extracts than any single contribution. In this study, the inhibitory effects of the ethanol extracts of thirty plant foods on the activities of secretory phospholipase $A_{2}$ ($sPLA_{2}$), cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2), and 12-lipoxygenase (12-LOX) were examined. Several legumes, mungbean sprout and some leaf vegetables inhibited the activity of $sPLA_2$, upstream enzyme of inflammation pathway. Only soybean sprout and mungbean sprout significantly inhibited 12-LOX activity. Although most of extracts inhibited the activities of both COX-1 and COX-2, water dropwort and amaranth showed selectivity for the inhibition of COX-2 over COX-1. Especially, mungbean showed anti-inflammatory property at both upstream and downstream of inflammation pathway with relatively low $IC_{50}$ values for $sPLA_{2}$ and COX-2 enzymes. Mungbean sprout exhibited inhibitory effects on all enzymes related to early and late inflammation and soybean sprout suppressed 12-LOX and COX-2 simultaneously, although the activities of these plants were showed at relatively high concentration. Therefore, mungbean, mungbean sprout, and soybean sprout appear to exhibit anti-inflammatory effects by combined inhibition of inflammatory enzymes.

Association of Leukotriene C4 Synthase Gene Polymorphism with Clinical Response to Montelukast in Childhood Asthma (소아 천식환자에서 Leukotriene C4 Synthase 유전자 다형태와 Montelukast의 임상적 효과와의 연관성)

  • Shin, Kyung Sue;Kim, Youn Woo
    • Clinical and Experimental Pediatrics
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    • 제48권7호
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    • pp.766-771
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    • 2005
  • Purpose : Cysteinyl leukotrienes are important inflammatory mediators in the pathogenesis of asthma; therefore interruption of cysteinyl leukotrienes by leukotriene receptor antagonists improves clinical symptoms in the management of patients with mild to moderate asthma. We evaluated whether clinical response to montelukast, a leukotriene receptor antagonist, in childhood asthma was predicted by genotypes of leukotriene $C_4$ synthase($LTC_4S$) promoter gene polymorphism. Methods : An 8-week prospective, open trial of montelukast was carried out in 161 children with mild to moderate asthma. Genotyping of $LTC_4S$ gene polymorphism was determined by restriction fragment length polymorphism. Results : The distribution of the $LTC_4S$ genotypes AA, AC, and CC was 70.8 percent, 23.6 percent, and 5.6 percent, respectively in asthma group and 74.0 percent, 22.6 percent, and 3.4 percent, respectively in control group. A statistically significant difference in the distribution of $LTC_4S$ genotype was not observed between the asthma and the control groups, and there was no significant difference between the $LTC_4S$ genotype and asthma severity. The responders to montelukast were significantly prevalent in the mild asthma group(P<0.05). There was no significant difference in the distribution of the responders compared to non-responders within genotype in the total asthma group or the moderate asthma group. However, the responsiveness for montelukast was significant difference within genotype for both AA and AC/CC in the mild asthma group : The AA genotype was more included in the responder group(P<0.05). Conclusion : In the mild persistent asthma group, the A allele of $LTC_4S$ polymorphism may be regarded as a predictable factor for clinical response to montelukast. However, LTC4S polymorphism was not significantly associated with the clinical response to montelukast in asthmatic children.

Toll-like receptor 9 expression and interferon-α secretion upon CpG-ODN stimulation in allergic subjects (알레르기 환자에서 TLR9 ligand인 CpG-ODN 자극에 의한 IFN-α 분비와 TLR9 발현)

  • Han, Man Yong;Jee, Hye Mi;Kim, Hyeong Yoon;Lee, Cho Ae;Cho, Hyo-Jin;Hwang, Seong-Gyu;Kim, Kyu-Earn
    • Clinical and Experimental Pediatrics
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    • 제52권9호
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    • pp.1015-1020
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    • 2009
  • Purpose:The aim of this study is to explore the effect of the Toll-like receptor 9 (TLR9) expressed in plasmacytoid dendritic cells (pDCs) that respond to antigen to Th2 immune deviation in allergic patients. Methods:Subjects consisted of 19 allergic patients and 17 healthy volunteers. Skin prick tests and nasal provocation tests were performed for the two groups. Peripheral blood mononuclear cells (PBMCs) were collected from subjects and analyzed for the Lineage Cocktail (CD3, CD14, CD16, CD19, CD20, CD56) (-), HLA-DR (+), and CD123 (+) using flow cytometry. In addition, we analyzed TLR9 mRNA by reverse transcriptase-polymerase chain reaction. The level of $interferon-{\alpha}$ ($IFN-{\alpha}$) of the PBMCs following stimulation with the TLR9 ligand CpG-ODN 2216 was also evaluated. Results:Analyses of CD123 (+) revealed a nearly similar distribution for the classical pDC markers in the allergic group ($0.1%{\pm}0.04%$) and in the controls ($0.25%{\pm}0.23%$). The mRNA levels of TLR9 on PBMCs were not different between the allergic group and the controls ($1.29{\pm}0.41$ vs. $1.25{\pm}0.23$, respectively). Additionally, the level of $IFN-{\alpha}$ in PBMCs exposed to stimuli of the TLR9 ligand CpG-ODN 2216 was not significantly different between the two groups ($911{\pm}829$ vs. $1,095{\pm}888pg/mL$, respectively). Conclusion:We found no evidence that TLR9-dependent immune responses in human pDCs are associated with allergic status.

A Experimental Study on Nitrous Oxide Formation in Direct Injection Diesel Engine (직접분사식 디젤엔진에서 아산화질소의 생성에 관한 실험적 연구)

  • Yoo, Dong-Hoon
    • Journal of the Korean Society of Marine Environment & Safety
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    • 제21권2호
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    • pp.188-193
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    • 2015
  • It has been generally recognized that $N_2O$(Nitrous Oxide) emission from marine diesel engines has a close correlation with $SO_2$(Sulfur Dioxide) emission, and diversity of fuel elements using ships affects characteristics of the $N_2O$ emission. According to recent reports, in case of existence of an enough large NO(Nitric Oxide) generated as fuel combustion, effect of the $SO_2$ emission in exhaust gas on the $N_2O$ formation is more vast than effect of the NO. Therefore, $N_2O$ formation due to the $SO_2$ element operates on a important factor in EGR(Exhaust Gas Recirculation) systems for NOx reduction. An aim of this experimental study is to investigate that intake gas of the diesel engine with increasing of $SO_2$ flow rate affects $N_2O$ emission in exhaust gas. A test engine using this experiment was a 4-stroke direct injection diesel engine with maximum output of 12 kW at 2600rpm, and operating condition was set up at a 75% load. A standard $SO_2$ gas with 0.499%($m^3/m^3$) was used for changing of $SO_2$ concentration in intake gas. In conclusion, the diesel fuel included out sulfur elements did mot emit the $SO_2$ emission, and the $SO_2$ emission in exhaust gas according as increment of the $SO_2$ standard gas had almost the same ratio compared with $SO_2$ rate in mixture inlet gas. Furthermore, the $N_2O$ element in exhaust gas was formed as $SO_2$ mixture in intake gas because increment of $SO_2$ flow rate in intake gas increased $N_2O$ emission. Hence, diesel fuels included sulfur compounds were combined into $SO_2$ in combustion, and $N_2O$ in exhaust gas should be generated to react with NO and $SO_2$ which exist in a combustion chamber.

Study on the structure of the articulation jack and skin plate of the sharp curve section shield TBM in numerical analysis (수치해석을 통한 급곡선 구간 Shield TBM의 중절잭 및 스킨플레이트 구조에 관한 연구)

  • Kang, Sin-Hyun;Kim, Dong-Ho;Kim, Hun-Tae;Song, Seung-Woo
    • Journal of Korean Tunnelling and Underground Space Association
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    • 제19권3호
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    • pp.421-435
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    • 2017
  • Recently, due to the saturation of ground structures and the overpopulation of pipeline facilities requires to development of underground structures as an alternative to ground structures. Thus, mechanized tunnel construction of the shield TBM method has been increasing in order to prevent vibration and noise problems in construction of the NATM tunnel for the urban infrastructure construction. Tunnel construction plan for the tunnel line should be formed in a sharp curve to avoid building foundation and underground structures and it is inevitable to develop a shield TBM technology that suits the sharp curve tunnel construction. Therefore, this study is about the structural stability technology of the articulation jack, shield jack and skin plate for the shield TBM thrust in case of the mechanized tunnel construction that is a straight and sharp curve line. The construction case study and shield TBM operation principle are examined and analyzed by the theoretical approach. The torque of the cutter head, the thrust of the articulation jack and the shield jack, the amount of over cutting for curve is important respectively in shield TBM construction of straight and sharp curve line. In addition, it is very important to secure the stability of the skin plate structure to ensure the safety of the inside worker. This study examines the general structure and construction of the equipment, experimental simulation was carried out through numerical analysis to examine the main factors and structural stability of the skin plate structure. The structural stability of the skin plate was evaluated and optimizes the shape by comparing the loads of the articulation jack by selecting the virtual soil to be applied in a straight and sharp curve line construction. Since the present structure and operation method of the shield TBM type in domestic constructions are very similar, this study will help to develop the localized shield TBM technology for the new equipment and the vulnerability and stability review.

Sex Steroid Hormone and Ophthalmic Disease (성호르몬과 안질환)

  • Kim, Jin-Ju;Yu, Hyeong-Gon;Ku, Seung-Yup
    • Clinical and Experimental Reproductive Medicine
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    • 제37권2호
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    • pp.89-98
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    • 2010
  • Sex and its tropic hormones influence the lacrimal system, corneal anatomy and disease, aqueous humor dynamics and glaucoma, crystalline lens and cataract, and retinal disease. Dry eye occurs especially frequently during pregnancy, oral contraceptive use, and after menopause, during which androgen levels decrease. Androgen control development, differentiation, and lipid production of sebaceous glands throughout the body, and androgen deficiency also leads to meibomian gland dysfunction and evaporative dry eye. On the other hand, estrogen causes a reduction in size, activity, and lipid production of sebaceous glands. Sex and its tropic hormones also influence the corneal anatomy and disease, and corneal thickening occurred on the second day of the menstrual cycle and around the time of ovulation and appeared to be related to estrogen levels. Fuchs' dystrophy is more commonly seen in postmenopausal women than men and may be linked to hormonal changes that occur with aging. In addition, overexpression of estrogen and progesterone receptors in the conjunctiva of vernal keratoconjunctivitis patients. Serum progesterone levels also may be associated with intraocular pressure especially in pregnant women, and for the women. For women with cataracts, hormone levels were typical of menopause, and there was a significant negative correlation between estradiol and follicular stimulating hormone levels. In addition, serum testosterone levels are associated with the development of diabetic retinopathy. Although the role of sex hormones on the eye is largely unknown, and the results should be interpreted with caution until replicated, the functions of sex hormones in ocular disease remains to be investigated, because they may be involved in structure and function of the ocular components, which are important in the pathogenesis of ocular disease.