• 자원환경지질
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• 제12권4호
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• pp.207-221
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• 1979

The studied area occupies the southern part of Haenam peninsula located in the southwestern corner of Korea. The stratigraphic sequences of the area are grouped into following three units in ascending order. (1) Late Cretaceous sedimentary rocks of Uhangri Formation which consist of the alternative beds of black shales and tuffaceous sediments, Hwangsan acidic fine grained tuffs and Jindo rhyolite flows. (2) Late Cretaceous biotite granite and acidic porphyries which intruded the Late Cretaceous sedimentary rocks. (3) Tertiary(?) pitchstone. The study purposes to delineate any of geochemical aspects on the deposition of the sequences, the average amounts of organic materials and the effect to the maturation of hydrocarbonization which has been occured by the intrusives. Sixty nine black shale samples were collected from Uhangri Formation in the northern and southern coasts of the peninsula. Organic carbons, total extracted organic matters and hydrocarbons were mainly determined by the Soxhlet extraction method, together with C-H-N elemental analyses. Based on the field and laboratory studies, the following interpretations have been obtained. (1) The paleohydrostatic condition of the sedimentation which took place was relatively calm and stable to delineate a lacustrine environment. (2) The amounts of organic material were more or less constant throughout the period of the deposition of the sediments. (3) The degree of hydrocarbonization of the Uhangri Formation in the northern coast was taken place higher than that in the southern coast due to the differences of thermal effect by the biotite granite which is assumed to be as a heat source in the area. Among the northern coast, some black shales in Uhangri and Mogsam areas which had been under the most moderate temperature environment snow symptomatic oily material, whereas, those in Sinseongri area do not, which were presumably to be intensive thermal alteration by the later acidic porphyries.

• Molecular & Cellular Toxicology
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• 제4권2호
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• pp.164-169
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• 2008

Methylmercury (MeHg) is known to have devastating effects on the mammalian nervous system. In order to characterize the mechanism of MeHg-induced neurotoxicity, we investigated the analysis of transcriptional profiles on human 8k cDNA microarray by treatment of $1.4{\mu}M$ MeHg at 3, 12, 24 and 48h in human neuroblastoma SH-SY5Y cell line. Some of the identified genes by MeHg treatment were significant at early time points (3h), while that of others was at late time points (48h). The early response genes that may represent those involved directly in the MeHg response included pantothenate kinase 3, a kinase (PRKA) anchor protein (yotiao) 9, neurotrophic tyrosine kinase, receptor, type 2 gene, associated with NMDA receptor activity regulation or perturbations of central nervous system homeostasis. Also, when SH-SY5Y cells were subjected to a longer exposure (48h), a relative increase was noted in a gene, glutamine-fructose-6-phosphate transaminase 1, reported that overexpression of this gene may lead to the increased resistance to MeHg. To confirm the alteration of these genes in cultured neurons, we then applied real time-RT PCR with SYBR green. Thus, this result suggests that a neurotoxic effect of the MeHg might be ascribed that MeHg alters neuronal receptor regulation or homeostasis of neuronal cells in the early phase. However, in the late phase, it protects cells from neurotoxic effects of MeHg.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
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• pp.242-242
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• 1994

Cortex mori (Morus alba L.), the root bark of mulberry tree, has been used as an antiphlogistic, diuretic, and expectorant in herbal medicine. The purpose of this study was to determine whether Cortex mori could inhibit the ovalbumin (OA) -induced late asthmatic reaction in guinea pigs. Guinea pigs were sensitized by two exposures to an aerosol of OA(1.0%) and then challenged with aerosolized antigen(2.0%), The animals were pretreated by three inhalations of the aerosoled Cortex mori either before antigen sensitization or cahllenge. Bronchoalveolar lavage fluid(BALF) and peripheral blood were collected at 17 hours after OA challenge. The cell populations in BALF and peripheral blood were examined to determine the changes of the relative proportions of eosinophils,neutrophils and mononuclear cells etc. Beta-glucuronidase activity in BALF was measured to evaluate the alveolar macrophage activation. OA-induced histamine release from guinea pig peritoneal fluid cells was measured by radioisotope enzymatic asssay. Results were as follows. The number of eosinophils, neutriphils and lymphocytes recovered in BALF were significantly increased in the 17h following aerosol challenge with OA. Among them, eosinophil and neutriphils were decreased remarkably in group that had been preinhalated with Cortex mori. The number of lymphocytes in BALF were not decreased in group pretreated with CM before sensitization but decreased in Group pretreated with CM before challenge. After OA challenge, the number of eosinophils in peripheral blood were markedly increased, but Cortex mori inhibited significantly the OA-induced eosinophilia. Beta-glucuronidase activity in the supernatants of BALF were significantly increased in the 17h following aerosol challenge with OA, however, pretreatment of Cortex mori had no influence on Beta-glucuronidase activity, suggesting that Cortex mori had no inhibitory effect on OA-induced alveolar macrophage activation. Cortex mori inhibited the OA-induced histamine release from guinea pig peritoneal fluid cells. From the above results, it is suggested that Cortex mori contains some substances with an activity to inhibit the the OA-induced late phase reaction of the bronchial asthma in guinea pigs.

• 한국학교보건학회지
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• 제23권2호
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• pp.162-171
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• 2010

Purpose: The purpose of this study was to find out the effect of hand washing education program on knowledge, attitude and practice of handwashing in elementary school. Methods: The subjects were 484 late school-aged children in Gyeonggi-do. Data were collected from Sep. 1 to Dec. 21, 2009. Results: 1) The handwashing education group (experimental group=E) showed higher score in knowledge of handwashing than the control group (C) (t=5.20, p<.001 ) as the E group scored 29.15(${\pm}3.24$) and the C group scored 27.52(${\pm}3.69$). 2) The E group showed higher score in attitude of handwashing than the C group (t=6.58, p<.001 ) as the E group scored 39.60(${\pm}4.33$) and the C group scored 36.96(${\pm}4.47$). 3) The E group showed higher score in practice of handwashing than the C group (t=2.64, p<.001). as the E group scored 45.90(${\pm}4.79$) and the C group scored 44.67(${\pm}5.33$). Conclusion: The experimental group showed significantly higher scores in knowledge, attitude, practice and cognition of handwashing. This proves that the handwashing program was effective. It is necessary to apply more systematic and various handwashing education programs for other grade at schools.

• The Plant Pathology Journal
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• 제20권1호
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• pp.67-74
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• 2004

A complete understanding of the epidemiological factors required for optimum for disease development facilitates the design of effective and reliable screening techniques and also disease prediction models. An attempt was made to study the effects of different temperatures ($15-35^{\circ}C$) and leaf wetness periods (4-24 h) on the development of late leaf spot (LLS) in three groundnut genotypes differing in their susceptibility to LLS infection. Irrespective of the genotype, the disease progress evaluated based on different components of resistance was maximum between $15-20^{\circ}C$ and minimum between $20-25^{\circ}C$. At temperatures $\geq$$30^{\circ}C$, LLS development was insignificant. The overall severity of LLS increased with an increase in the leaf wetness period from 4 h to 12 h a day. Further increase of wetness period to 16 h resulted in a rapid increase in the severity. Thereafter, the disease severity gradually decreased with an increase in the wetness period. The effect of temperature and wetness periods on the individual component of disease quantification was not uniform compared between genotypes with different levels of susceptibility/resistance to LLS infection. The results of this study indicate that temperature and leaf wetness period are critical in late leaf spot screening programs since the expression of disease symptoms measured from disease initiation till defoliation, varied differently in the test genotypes with respect to change in these two parameters.

• 통상정보연구
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• 제18권1호
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• pp.179-208
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• 2016

본 연구는 시장의 후발주자가 선발우위를 극복하기 위한 전략적 수단으로 사용할 수 있는 요소브랜딩전략의 효과를 살펴보고자 한다. 구체적으로 브랜드성분의 원산지정보와 요소브랜딩제품의 제시된 가격수준이 소비자 평가에 미치는 영향에 관해서 연구하고자 한다. 본 연구는 실험연구로 진행되었으며, 총 400명의 피험자를 대상으로 2개의 실험을 실시하였다. 연구결과, 연구1에서는 요소브랜드의 시장지위 및 원산지정보는 소비자의 요소브랜딩 제품 평가에 유의한 영향을 미치는 것으로 나타났다. 연구2에서는 시장진입순서와 요소브랜드의 원산지정보가 소비자의 요소브랜딩 제품에 대한 평가에 미치는 영향은 제시되는 제품의 가격수준에 의해 조절되는 것으로 나타났다. 본 연구의 내용은 후발브랜드의 선발우위 극복을 위한 전략적 방안을 제안하고, 후발기업의 브랜드 운용전략에 대한 시사점도 제시하고 있다.

• 대한지리학회지
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• 제38권6호
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• pp.906-921
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• 2003

본 연구는, 미국 지방정부의 성장관리 규제가 유발시키는 지역주택시장내 가격상승효과를 이해하기 위해, 성장관리가 가질 수 있는 주택건설 억제 효과를 실증적으로 분석했다. 실증 분석은 1980년대말 캘리포니아내 지방 정부를 대상으로 했으며. 공간계량경제 모델을 활용했다. 분석을 통해. 본 연구는 성장관리의 주택가격상승효과에 관한 기존 연구의 한계를 극복하는 데 기여하고자 했다. 즉, 캘리포니아 주와 같은 비교적 광범위한 지역에 적용되는 일반화된 결과를 얻었고. 개별 성장관리 규제가 주택건설에 미치는 영향력을 고찰했으며, 아울러 공간효과, 특히 공간적 자기상관을 분석모델에 반영시킴으로써 분석의 설명력을 제고했다. 모델링 결과, 주거용도지역내 허용개발밀도를 저하시키려는 일련의 성장관리규제는 주택건설을 억제시키는 효과를 보였다. 하지만. 주택건설 및 도시성장을 지방정부가 설정한 지역내에 한정시키는 규제는, 오히려, 주택건설을 증가시키는 효과를 보였다. 연간 인구증가 및 건축허가건수를 제한하는 규제와 주택건설업자의 공공하부구조 공급을 강제하는 법규는 주택건설에 유의한 영향을 미치지 않은 것으로 나타났다.

• 한국콘텐츠학회논문지
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• 제17권5호
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• pp.100-113
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• 2017

본 연구의 목적은 노년기 활동 참여가 삶 만족과 자아통합감에 미치는 영향을 확인하고, 활동 참여와 삶 만족, 활동참여와 자아통합감의 관계에서 삶의 의미의 매개효과를 확인하는 것이다. 은퇴한 55세 이상의 성인 700명(남자 350명, 여자 350명)이 설문조사에 응답하였다. AMOS를 활용하여 구조방정식 모형을 분석한 결과, 제안된 모형이 적절한 것으로 나타났다. 분석 결과 활동 참여의 수준이 높을수록 삶 만족이 높으며, 자아통합감이 높은 것으로 나타났다. 또한 활동 참여와 삶 만족, 활동 참여와 자아통합감의 관계에서 삶의 의미가 매개효과를 가지는 것으로 확인되었다. 마지막으로 노년기 삶 만족과 자아통합감에 있어서 활동 참여와 삶의 의미가 가지는 역할과 본 연구의 한계점에 대해 논의하였고 후속 연구에 대해 제안하였다.

• Animal Bioscience
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• 제35권11호
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• pp.1744-1751
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• 2022

Objective: The present study aimed to investigate the effect of xylo-oligosaccharides (XOS) administration on egg production, reproductive hormones, serum lipids and adipokines of hens at the late cycle of reproduction. Methods: Four treatments included control (basal diet) and XOS addition at 2.0 (XOS-2), 4.0 (XOS-4), or 6.0 (XOS-6) g/kg of diet using 288 commercial Hy-Line brown hens from 73 to 84 wk of age. Egg production, body fat deposition, reproductive tract and hormones, lipid metabolism and adipokines were determined. Results: At 84 wk, compared to the control, XOS supplementation at the three doses increased (p<0.001) egg-laying rates by 13.2% averagely, which led to a higher egg mass by 131 g/hen throughout the whole trial period. Abdominal fat and skinfold of XOS treatments were decreased (p<0.001) by 26.1% and 18.6%, respectively; large follicles and ovary weight were increased (p<0.001) by 0.73 follicle/hen and 18.6%, respectively. For serum parameters, cholesterol and triglyceride were decreased (p<0.001) by 17.5% and 29.2%, respectively; luteinizing hormone, follicle-stimulating hormone, and progesterone were increased (p≤0.001) by 16%, 31%, 29%, respectively; adiponectin and visfatin were increased (p<0.001) by 34% and 44%, respectively; but chemerin and leptin were decreased (p≤0.001) by 22% and 14%, respectively. With the increased XOS doses, linear decreases (p<0.05) were found on abdominal skinfold and serum triglyceride. Conclusion: The obtained data indicate that XOS can be used as an additive to improve fecundity by beneficially modulating fat deposition, lipid metabolism, reproductive hormones, and adipokines of hens at the late cycle of reproduction.

• The Korean Journal of Pain
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• 제36권1호
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• pp.51-59
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• 2023

Background: This study investigated the effect of an excess and a deficit of spinal 5-hydroxytryptamine (5-HT) on the mechanical allodynia and neuroglia activation in a rodent pain model of carrageenan inflammation. Methods: Male Sprague-Dawley rats were implanted with an intrathecal (i.t.) catheter to administer the drug. To induce an excess or deficit of 5-HT in the spinal cord, animals were given either three i.t. 5-HT injections at 24-hour intervals or a single i.t. injection of 5,7-dihydroxytryptamine (5,7-DHT) before carrageenan inflammation. Mechanical allodynia was measured using the von Frey test for 0-4 hours (early phase) and 24-28 hours (late phase) after carrageenan injection. The changes in the activation of microglia and astrocyte were examined using immunofluorescence of the dorsal horn of the lumbar spinal cord. Results: Both an excess and a deficit of spinal 5-HT had no or a minimal effect on the intensity of mechanical allodynia during the early phase but prevented the attenuation of mechanical allodynia during the late phase, which was observed in animals not treated with i.t. 5-HT or 5,7-DHT. Animals with an excess or deficit of 5-HT showed stronger activation of microglia, but not astrocyte, during the early and late phases, than did normal animals. Conclusions: Imbalance in the descending 5-HT pathway in the spinal cord could aggravate the mechanical allodynia and enhance the activation of microglia, suggesting that the spinal 5-HT pathway plays an essential role in maintaining the nociceptive processing in balance between facilitation and inhibition in inflammatory pain caused by carrageenan inflammation.