• 한국초등과학교육학회지:초등과학교육
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• 제39권3호
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• pp.399-411
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• 2020

This study aims to explore how elementary students perceive and approach the issue of plastic debris in marine habitats by examining students' perspectives on the ecosystem and environmental solutions. The study was conducted to 143 Grade Four elementary school students in Seoul. After implementing two class-units on plastic waste, students' constructed responses on the problem of and solutions to plastic debris in marine habitats were collected. Data were analyzed through semantic network analysis and the keywords were visualized to reflect their relationships. Furthermore, students' responses on how they perceive environmental problems were further analyzed based on the following analysis criteria: students' perspectives on the ecosystem, the level of complexity of food chain(s), and the scope of their perspective. Also, student responses on environmental solutions were classified to be either at a personal or social level. Through semantic network analysis, keywords identified for students' perceptions on the problem were the sea, plastic, debris, animals, living things, humans, extinction, while keywords extracted for the solutions were plastic, debris, recycling, disposable, and I. Based on the analysis criteria, it was found that students were well aware of the food chain concept, could perceive the ecosystem as having comprised of both biotic and abiotic factors, and could approach the problem beyond the scope of the marine environment. Also, most students mentioned the solutions only at a personal level. Based on the findings, implications on how to move forward in educating environmental issues related to the ecosystem in science education is further discussed.

• 한국독성학회:학술대회논문집
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• 한국독성학회 1997년도 국제심포지움 및 추계학술대회
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• pp.38-42
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• 1997

인간성장 호르몬은 191개의 아미노산으로 구성된 펩타이드 호르몬의 일종으로 사람의 뇌하수체에서 분비된다. 본연구의 목적은 저렴한 가격의 재조합 성장호르몬을 안정적으로 공급함은 물론 부작용을 최대한으로 줄이는데 있다. 효모에서의 성장호르몬 재조합 과정은 유전자조작과 이에따른 정제기술의 확립을 시작으로 물리 화학적 또는 생물학적 물성 연구, 다양한 전임상 시험 및 임상 시험의 단계를 수행한 후, 인허가 과정을 거쳐서 완료되었다. 다양한 실험 결과에 의하면 당소에서 재조합 기술로 생산한 고순도의 인간성장 호르몬은 안정된 물성을 보유하고 있을 뿐만아니라 전임상 시험 결과 인체 투여용량의 수십배의 고용량을 투여하여도 별다른 독성 증상을 관찰할 수 없었으며, 임상 시험에서도 대상 환아의 신장이 지속적으로 성장하는 등 만족할 만한 결과를 보여 주었다.

• Parasites, Hosts and Diseases
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• 제54권1호
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• pp.15-20
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• 2016

Toxoplasmosis is an important zoonotic disease that can cause abortion in humans and animals. The aim of this study was isolation and subsequent genotyping of Toxoplasma gondii isolates in ovine aborted fetuses. During 2012-2013, 39 ovine aborted fetuses were collected from sheep flocks in Khorasan Razavi Province, Iran. The brain samples were screened for detection of the parasite DNA by nested PCR. The positive brain samples were bioassayed in Webster Swiss mice. The serum samples of mice were examined for T. gondii antibodies by IFAT at 6 weeks post inoculation, and T. gondii cysts were searched in brain tissue samples of seropositive mice. The positive samples were genotyped by using a PCR-RLFP method. Subsequently, GRA6 sequences of isolates were analyzed using a phylogenetic method. The results revealed that T. gondii DNA was detected in 54% (20/37, 95% CI 38.4-69.0%) brain samples of ovine aborted fetuses. In bioassay of mice, only 2 samples were virulent and the mice were killed at 30 days post inoculation, while the others were non-virulent to mice. The size of cysts ranged $7-22{\mu}m$. Complete genotyping data for GRA6 locus were observed in 5 of the 20 samples. PCR-RLFP results and phylogenetic analysis revealed that all of the isolated samples were closely related to type I. For the first time, we could genotype and report T. gondii isolates from ovine aborted fetuses in Khorasan Razavi Province, Iran. The results indicate that the T. gondii isolates are genetically related to type I, although most of them were non-virulent for mice.

• 한국융합학회논문지
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• 제9권4호
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• pp.127-135
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• 2018

인간은 선과 악을 함께 가지고 있기 때문에 양면적이라 할 수 있다. 이러한 인간은 악을 더욱 구체화하기 위해 악을 형상화하여 조형적 요소로 악의 상징물을 만들었다. 이에 본 연구자는 악의 개념부터 인간이 가지고 있는 악에 본질이 상징물로 표현되었을 때 나타나는 조형성에 관하여 조사 분석해 보고자 하였다. 조형성의 분류 항목을 구축하여 설문지를 작성하여 다음과 같은 분석의 결과를 도출하였다. 구성유형에서는 문자보다는 그림 또는 기호로 표현되었으며, 표현대상에서는 신화 속 인물과 동물의 형태로 나타났다. 레이아웃에서는 방사형이 가장 많이 나타났으며 묘사방법에서는 단순성과 복잡성의 형태로 외곽형태는 원형이 가장 높게 나타났다. 이러한 구성유형의 항목들이 높은 점수를 보인 상징물은 서로간의 조형적인 상관관계로 그려지고 사용되었으며, 발전해 왔다는 것을 알 수 있었다.

• 한국축산식품학회지
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• 제38권2호
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• pp.391-402
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• 2018

The aim of the present work was to provide information about Enterococcus strains isolated from pre-packaged chicken samples in Ankara (Turkey), focusing on their prevalence, phenotypic and genotypic characteristics, and antibiotic resistance. We report the first study on the occurrence of antibiotic resistant enterococci in pre-packaged chicken samples in Ankara. A total of 97 suspicious enterococcal isolates were identified from 122 chicken samples. All isolates were identified to species level by phenotypic and molecular methods. In the 16S rDNA sequence analysis, Enterococcus faecium (61.85%) and Enterococcus faecalis (38.15%) were found to be the most frequently detected Enterococcus spp. Of the 97 isolates tested for hemolytic activity, 12.37% enterococcal strains were ${\beta}$-hemolytic. ${\beta}$-Hemolysin was most prevalent among E. faecium (58.33%) compared to E. faecalis (41.66%). Disk diffusion method was used for determining of antibiotic resistance. The analysis of the antimicrobial resistance of the 97 Enterococcus isolates revealed that the resistance to kanamycin (98.96%), rifampicin (80.41%) and ampicillin (60.82%) was most frequent. Furthermore, resistance to erythromycin (38.14%) and ciprofloxacin (34.02%) was also observed. The frequencies of resistance to tetracycline (9.27%), penicillin G (8.24%), and chloramphenicol (3.09%), gentamicin (2.06%) and streptomycin (1.03%) were low. None of the isolates was resistant to vancomycin. Multi-drug resistance was found in 97.93% of Enterococcus strains. E. faecium strains showed a more resistant phenotype than E. faecalis strains according to the antibiotic resistance levels. The results of this study indicated that chicken meat is a potential reservoir for the transmission of antibiotic resistance from animals to humans.

• 대한의용생체공학회:의공학회지
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• 제14권1호
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• pp.89-96
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• 1993

During high frequency ventilation (HFV), mean alveolar pressure has been measured to increase with mean airway opening pressure controlled at a constant level in both humans and experimental animals. Since this phenomenon could potentiate barotrauma limiting advantages of HFV, the present study theoretically predicted the difference between menu alveolar and airway opening pressures ($MP_{alv}$). In a Weibel's trumpet airway model, approximated formula for $MP_{alv}$ was derived based on momentum conservation assuming a uniform velocity profile. The prediction, equation was a func pion of gas density($\rho$), mean flow rate(Q), and diameter of the airway opening where the pressure measurement was made($D_0$) : $MP_{alv}=4{\rho}(Q/D_0^{2})^2$. This was a result of the difference in crosssectional area between the alveoli and the airway opening. A simple aireway model experiment was performed and the results well fitted to the prediction, which demonstrated the validity of the present analysis. Previously reported $MP_{alv}$ data from anesthetized dogs in supine position were comparable to the predicted values, indicating that the observed dissociation between mean alveolar and airway opening pressures during HFV can be explained by this innate geometric (or cross-sectional area) asymmetry of the airways. In lateral position, however, the prediction substantially underestimated the measurements suggesting involvement of other important physiological mechanisms.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제13권4호
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• pp.381-390
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• 1991

The purpose of this study was to select the absorbable suture material with the lowest level of foreign body reaction in the extraoral field. The absorbable sutures tested were polyglactin 910(Vicryl), polyglycolic acid(Dexon), and chromic gut. Black silk served as to control suture. Eighteen domestic rabbits served as the animal model for testing purposes. After shaving the fur, A six centimeter incision was made in the hind quarter of all eighteen animals. Each wound was then closed wit two Vicryl, two Dexon, and two chromic gut sutures. All wounds were closed in the same manner. A similar wound was made on the oppsite side and closed with black silk suture. Three rabbits were then sacrificed on postoperative day one, three, seven fourteen, twenty-one, and twenty-eight. The surgical sites were then examined histologically. 1. On days one, three, and seven all suture materials as a similar severe level of inflammatory response. On the fourteenth day the inflammatory reaction of Vicryl was minimal, chromic gut was moderate, and Dexon was severe, Black silk control groups demosnstrated the most severe levels of inflammation of all sutures tested from day fourteen to twenty-eight. 2. On the fourteenth day all absorbable suture materials demonstrated similar minimal levels of resorption. At twenty-eight days Vicryl demonstrated a greater amount of resorption than Dexon or cromic gut suture. There was no resorption noted in the black silk control groups through day twenty-eight. 3. Due to its decreased level of inflammatory response in the animal model, Vicryl might be expected to as a decreased level of response in humans. It is felt that Vicryl is preferred to Dexon or chromic gut for extraoral suturing.

• 대한미생물학회지
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• 제22권4호
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• pp.393-402
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• 1987

The halophilic bacterium Vibrio vulnificus, previously called lactose-positive(L+) Vibrio and Beneckea vulnifica, causes acute, fulminating wound infections and septicemia in humans. Septicemia is very serious infection with a fatality rate of about 50%. Most patients with primary septicemia due to V. vulnificus have preexisting liver disease. V. vulnificus also cause severe wound infections usually after trauma and exposure to marine animals or the marine environment. The mortality rate is not nearly as high as in primary septicemia caused by this organism. In most cases human disease results from ingestion of contaminated seafood or from infection of a wound, frequently of seawater or crab origin. The author made an attempt to isolation of the V vulnificus from seawater, seamud, fish, shellfish, and algae on the southern sea of Korea from January to September in 1987, using for the purpose of vaccine preparation. The author investigated for bacteriological identification, hemolysis and determination of serotypes of isolated V. vulnificus strains. Eighty-five strains(5.9%) out of 1450 specimens collected of V. vulnificus were isolated. The distribution of the 85 isolates were as follows: 21 strains from seawater, 11 strains from seamud, 28 strains from fish, 19 strains from shellfish, and 6 strains from algae, respectively. All 85 isolates were positive reaction on human blood agar. The distribution of serotypes of V. vulnificus isolates were O1 to O8: 13 strains of O1, 6 strains of O2, 11 strains of O3, 9 strains of O4, 10 strains of O5, 7 strains of O6, 15 strains of O7, and 10 strains of O8, respectively. Eighty-one strains showed agglutination with O antisera, but 4 strains failed to show agglutination. In this study, the author suspected that serotypes of V. vulnificus isolates distributed also in the seaside of Korea as well as in most seaside of the world, and new serotypes were in existence in the seaside of Korea except reported up to now.

• Clinical and Experimental Reproductive Medicine
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• 제40권4호
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• pp.155-162
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• 2013

Objective: Stress is known to be an inhibitor of the reproductive hypothalamic-pituitary-gonadal (HPG) axis. However, the neural and molecular connections between stress and reproduction are not yet understood. It is well established that in both humans and rodents, kisspeptin (encoded by the kiss1 gene) is a strong stimulator of the HPG axis. In the present study we hypothesized that endocannabinoids, an important neuromodulatory system in the brain, can act on the HPG axis at the level of kiss1 expression to inhibit reproductive function under stress. Methods: Adult male Wistar rats were unilaterally implanted with an intracerebroventricular cannula. Afterwards, the animals were exposed to immobilization stress, with or without the presence of the cannabinoid CB1 receptor antagonist AM251 (1 ${\mu}g/rat$). Blood samples were collected through a retro-orbital plexus puncture before and after stress. Five hours after the stress, brain tissue was collected for reverse transcriptase-quantitative polymerase chain reaction measurements of kiss1 mRNA. Results: Immobilization stress (1 hour) resulted in a decrease in the serum luteinizing hormone concentration. Additionally, kiss1 gene expression was decreased in key hypothalamic nuclei that regulate gonadotrophin secretion, the medial preoptic area (mPOA), and to some extent the arcuate nucleus (ARC). A single central administration of AM251 was effective in blocking these inhibitory responses. Conclusion: These findings suggest that endocannabinoids mediate, at least in part, immobilization stress-induced inhibition of the reproductive system. Our data suggest that the connection between immobilization stress and the HPG axis is kiss1 expression in the mPOA rather than the ARC.

• 디지털융복합연구
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• 제17권2호
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• pp.363-371
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• 2019

본 연구의 목적은 빅토르 위고(Victor Hugo)의 <크롬웰, Cromwell,1827> 서문의 그로테스크한 특성을 살피고, 니체의 고대 <그리스 비극>에 나타난 '사티루스(Satyros)'의 그로테스크한 현상을 빅토르 위고의 그로테스크와 차이점 및 공통점을 규명하기 위함이었다. 또한, 빅토르 위고와 니체의 공통점은 중세에 관심이 있었는데, 어떤 차이가 있는지 살펴보고자 했다. 연구의 주요결과는 빅토르 위고의 그로테스크 현상은 니체의 <그리스 비극>에서 디오니소스 극장의 '사티루스'에서 드러난다. 그것을 분류하면 첫째, 외형적인 부분에서 인간과 동물이 혼합된 형상을 한다. 둘째, '사티루스'가 익살스럽고 우스꽝스러운 분위기에서 가면을 그로테스크한 소재로 활용한 부분이다. 그로테스크에 대한 미학적, 철학적 정의가 세기마다 다양한 방법으로 있었지만, 아직도 그로테스크에 대해서 연구가 부족한 실정이다. 향후 후속연구는 시간의 흐름에 따른 사회적 현상에서 세부적인 연구가 진행되야 할 것이다.