Testicular Morphology of Hanwoo bull at 7 to 17 Months of Age

Sung-Sik Kang,Sang-Rae Cho1,Ui-Hyung Kim,Kim Hyeong-Cheol,Chung Ki-Yong,Jang Sun-Sik,Si-Dong Kim 한국동물생명공학회(구 한국동물번식학회) 2016 발생공학 국제심포지엄 및 학술대회 Vol.2016 No.10

Three-Dimensional Porous Collagen/Chitosan Complex Sponge for Tissue Engineering

Kim, Sung Eun,Cho, Yong Woo,Kang, Eun Jung,Kwon, Ick Chan,Lee, Eunhee Bae,Kim, Jung Hyun,Chung, Hesson,Jeong, Seo Young The Korean Fiber Society 2001 Fibers and polymers Vol.2 No.2

A three-dimensional, porous collagen/chitosan complex sponge was prepared to closely simulate basic extracellular matrix (ECM) constitutes, collagen and glycosaminoglycan. The complex sponge was prepared by a lyophilization method and had the regular network with highly porous structure, suitable for cell adhesion and growth. The pores were well interconnected, and their distribution was fairly homogeneous. The complex sponge was crosslinked using 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS) to increase its boilogical stability and enhance its mechanical properties. The crosslinking medium has a great effect on the inner structure of the sponge. The homogeneous, porous structure of the sponge was remarkably collapsed in an aqueous crosslinking medium. However, the morphology of the sponge remained almost intact in a water/ethanol mixture crosslinking milieu. Mechanical properties of the collagen/chitosan sponge were significantly enhanced by EDC-mediated crosslinking. The potential of the sponge as a scaffold for tissue engineering was investigated using a Chinese hamster ovary cell (CHO-K1) line.

Estimating population density of Nicrophorus quadripunctatus (Coleoptera: Silphidae) in Korea

Kim Do‐Sung,Cho Young‐Bok,Han Yong‐Gu 한국곤충학회 2020 Entomological Research Vol.50 No.11

Estimating the population density of organisms is of great concern to ecologists and much effort has been put into making accurate assessment of population levels in nature. We evaluated the trapping web (TW) method for the determination of the density of species of burying beetles. We found eight and six species of burying beetles at Beopjusa and Ssanggok‐ri areas, respectively. Most of the species population comprised Nicrophorus quadripunctatus, with densities of 65 and 195 per ha for Beopjusa and Ssanggok‐ri areas, respectively. Moreover, the flight intercept trap (FIT) method from 2003 to 2007 also revealed the same trend: Beopjusa temple (2928) to Ssanggok‐ri (5835). However, the differences in number of individuals were probably due to the differences in the methods and the length of the trapping period. The populations of N. quadripunctatus exist as metapopulations, making accurate assessment of the population densities extremely difficult. We hypothesized that the TW method could accurately estimate population densities extrapolated from patch population size per area.

아파트경매에서 낙찰가율의 결정요인에 대한 연구

조상용(Cho, Sang-Yong),박승록(Park, Seung-Rok) 한국주거환경학회 2015 주거환경(한국주거환경학회논문집) Vol.13 No.4

In this paper, we study the highest bid price determination mechanism of the court auction markets for apartments that are under distraint because of the insolvency of the owner of the apartments. In addition to the typical variables used in previous literatures on the determination of highest bid price, we add the variables that represent the characteristics of the tenants categorized by the priority order of the tenants’ deposits in the distribution process of the money obtained from the auction of the apartments. Unlike our general perception, the results show that the presence of pretense tenants on the priority list of the distribution of dividend from the auction hardly affects the determination of the highest bid price. In addition, the presence of legal counter power of tenants against the landlord does not affect the highest bid price, either. The first policy implication of this paper is that to set up a fair institutional mechanism in court auction market for apartments under distraint, the auction court needs to ask the applicant of the auction to prove whether the listed tenants are true to eliminate the pretense tenants. The second policy implication is that the court needs to disapprove the seniority of the pretense tenants’ claim on the distribution of dividends from auction of the apartments.

소아에서 간질발작의 임상양상과 뇌파검사의 관계

이승현(Seung Hyeon Lee),손동우(Dong Woo Son),은병욱(Byung Wook Eun),심소연(So Yeon Sim),최덕영(Deok Young Choi),선용한(Yong Han Sun),조강호(Kang Ho Cho0, 류 일(Eell Ryoo),전인상(In Sang Jeon0, 차 한(Hann Tchah) 대한소아신경학회 2009 대한소아신경학회지 Vol.17 No.2

목적:발작의 분류는 발작의 원인, 예후를 추정하거나 항경련제를 선택하는 데 있어 매우 중요하며 뇌파검사는 발작의 종류를 구분하고 적절한 치료를 하기 위해 시행하는 중요한 검사이다. 저자들은 소아에서 임상적 발작이 확실한 경우 간질발작의 임상양상과 뇌파검사 간의 일치 정도를 알아보고자 한다. 방법:2000년 1월 1일부터 2008년 9월 30일까지 1회 이상의 간질발작을 주소로 가천의대 길병원 소아청소년과에 방문한 환자 중 본원에서 처음으로 뇌파검사를 시행한 환자를 대상으로 하였다. 발작의 임상양상은 목격자와 본인의 설명을 기록한 의무기록지를 기준으로 하여 부분발작과 전신발작으로 분류하였고 뇌파검사는 발작간간질양방전을 기준으로 정상과 비정상으로 분류하였으며 각성과 수면상태 모두에서 시행하였다. 결과:총 461명의 환자의 뇌파검사 시의 평균 연령은 6.7세였고 남자는 247명, 여자는 214명이었다. 전체 환자에서 발작의 임상양상은 부분발작이 310명, 전신발작이 187명이었다. 각성뇌파검사에서 비정상은 158명으로 부분발작파가 118명, 전신발작파가 59명, 두 가지 발작파가 한 환자에서 나온 경우가 19명이었고, 수면뇌파검사에서는 비정상이 239명으로 부분발작파가 196명, 전신발작파가 77명, 두 가지 발작파가 한 환자에서 나온 경우가 34명이었으며 전체 환자에서는 비정상이 273명으로 부분발작파가 216명, 전신발작파가 97명, 두 가지 발작파가 한 환자에서 나온 경우가 40명이었다. 간질증후군은 전체 환자 중 90명에서 관찰되었다. 146명(41.5%)의 부분발작과 44명(23.4%)의 전신발작 및 79명(87.8 %)의 간질증후군이 뇌파소견과 일치하였다. 결론:영유아 및 소아에 있어 발작을 진단할 때에는 발작양상 분 아니라 정확한 뇌파소견을 세심하게 고려하여야 한다. Purpose:Electroencephalography(EEG) is an essential method carried out for classifying seizures and taking appropriate treatment. The aim of this study is to investigate the concordance between clinical findings of epileptic seizures and EEG in children. Methods:We enrolled 461 patients from those who visited Gil hospital from January 1, 2000 to September 30, 2008 with the chief complaint of epileptic seizure more than once and checked their first EEG at the same hospital. The clinical findings of seizure were based on the charts and interictal waking and sleep EEGs were done. Results:The mean age of the patients was 6.7 years old. 497 epileptic seizures occurred and its clinical finding included 310 of partial seizures and 187 of generalized seizures. In 315 waking EEG 158 were abnormal including 118 of partial seizures, 59 of generalized seizures and 19 of both seizures, in 431 sleep EEG 239 were abnormal including 196 of partial seizures, 77 of generalized seizures and 34 of both seizures, and in waking and/or sleep EEG 273 were abnormal including 216 of partial seizures, 97 of generalized seizures and 40 of both seizures. Epileptic syndromes were observed in 90 patients. 146(41.5%) of partial seizures, 44(23.4%) of generalized seizures, and 79(87.8%) of epileptic syndromes accorded with EEG. Conclusion:When diagnosing seizures in children, we must consider not only clinical findings but also accurate EEG findings.

초등 교과교육학의 성격과 내용구조 연구

유한구(Han Ku Ryu),장성모(Sung Mo Chang),송광용(Kwang Yong Song),조주연(Joo Yun Cho),이학주(Hak Ju Lee) 한국초등교육학회 1997 초등교육연구 Vol.11 No.1

이 연구는 교과교육과 교과교육학의관계, 그리고 교과교육학과 교육학의 관계등을 분석하고, 그 결과를 토대로 하여 초등학교 교과교육과 교육대학 교과교육학 교육의 실제를 정확히 이해하고 그 발전 방향을 탐색하기 위한 것이다. 일반적으로, 교과교육학은 교육학에서 제시하고 있는 교육과정의 구성및 교육방법상의 일반 원리를 교과교육이라는 특수한 사태에 적용하는 과정에 관심을 두는 이론으로 간주되고 있다. 이 관점에 의하면, 교과교육학은 교육학의 일반적 원리에 따라 교과교육이라는 특수한 맥락에 처방을 내리기 위한 것으로 파악된다. 이 관점을 교과와 그것을 가르치는 교사의 삶을 사실상 별개의 것으로 분리하는 것이며, 그와 동일한 이유에서 교과교육학과 교과교육학자의 삶 또한 별개의 것임을 전제하는 것이다. 그러나 교과교육과 교과교육학, 그리고 교과교육학과 교육학의 관계는 이론에서 실제로 나아가는 앞의 방향과는 정반대 방향에서도 이해될 수 있다. 이 관점에 의하면, 교과교육학은 교과교육 실제에 처방을 내리기 위한 것이 아니라 그 실제를 기술하고 정당화하기 위한 것으로 파악된다. 교과교육과 교과교육학의 관련이 이렇게 파악될 때, 교과 교육학은 교사나 교과교육학자에게 자신이 지금 하는 일이 자신의 삶과 결코 무관한 것이 아니라는 믿음을 심어 주게 되며, 나아가 그들 자신이 참여하고 있는 초등학교나 교육대학의 교육실제를 기술하거나 정당화하려고 할 때 반드시 필요한 개념적 도구를 제공해 줄 수 있게 된다. 바로 여기에 교과교육학에 관한 종래의 접근과는 구분되는 새로운 접근방식이 요구되는 이유가 있다. The purpose of this study is threefold: The first is to analyse the relations between subject education and subject pedagogy, and between subject pedagogy and general pedagogy. The second is, based on the analysis result, to have the precise understanding of teaching various subjects in the elementary school, and of teaching subject pedagogy in the university of education. The third is to search for the desirable direction of developing the elementary education and the teacher education. Subject pedagogy is usually defined as a theory which is interested in the process of applying pedagogical principles regarding curriculum organization and teaching methods to specific teaching situations, that is, subject education situations. However, this definition has a limitation, because it assumes that a subject and the teacher's life who teaches the subject are separated from each other, and that subject pedagogy and the scholar who studies subject pedagogy are also separated. The relationship between subject teaching and subject pedagogy, and between subject pedagogy and general pedagogy can be understood with quite different viewpoint. This new viewpoint, which is the major discussion matter of this study, assumes that subject pedagogy is never separated from the life of subject teacher/subject pedagogist. This viewpoint will reveal the theoretical features of subject pedagogy better, and give us new meaning on the life of teachers/subject pedagogists. The subject pedagogy in the correct sense should provide teachers/pedagogists with the conceptual instrument based on the new viewpoint. This conceptual instrument will make teachers/pedagogists be able to describe, explain, and validate their own educational practice-such as the content structure of each subject-in the elementary school or the university of education.

Analysis of risk factors for post-operative ileus and prognostic factors for oncologic outcome after prostective loop ileostomy for low anterior resection

Sung Chul LEE,Jung Wook HUH,Woo Yong LEE,Seong Hyeon YUN,Hee Cheol KIM,Yong Beom CHO,Yoon Ah PARK,Jung Kyong SHIN 대한외과학회 2019 대한외과학회 학술대회 초록집 Vol.2019 No.10

Tetragonal Phase Germanium Nanocrystals in Lithium Ion Batteries

Cho, Yong Jae,Im, Hyung Soon,Kim, Han Sung,Myung, Yoon,Back, Seung Hyuk,Lim, Young Rok,Jung, Chan Su,Jang, Dong Myung,Park, Jeunghee,Cha, Eun Hee,Cho, Won Il,Shojaei, Fazel,Kang, Hong Seok American Chemical Society 2013 ACS NANO Vol.7 No.10

<P>Various germanium-based nanostructures have recently demonstrated outstanding lithium ion storage ability and are being considered as the most promising candidates to substitute current carbonaceous anodes of lithium ion batteries. However, there is limited understanding of their structure and phase evolution during discharge/charge cycles. Furthermore, the theoretical model of lithium insertion still remains a challenging issue. Herein, we performed comparative studies on the cycle-dependent lithiation/delithiation processes of germanium (Ge), germanium sulfide (GeS), and germanium oxide (GeO<SUB>2</SUB>) nanocrystals (NCs). We synthesized the NCs using a convenient gas phase laser photolysis reaction and attained an excellent reversible capacity: 1100–1220 mAh/g after 100 cycles. Remarkably, metastable tetragonal (ST12) phase Ge NCs were constantly produced upon lithiation and became the dominant phase after a few cycles, completely replacing the original phase. The crystalline ST12 phase persisted through 100 cycles. First-principles calculations on polymorphic lithium-intercalated structures proposed that the ST12 phase Ge<SUB>12</SUB>Li<SUB><I>x</I></SUB> structures at <I>x</I> ≥ 4 become more thermodynamically stable than the cubic phase Ge<SUB>8</SUB>Li<SUB><I>x</I></SUB> structures with the same stoichiometry. The production and persistence of the ST12 phase can be attributed to a stronger binding interaction of the lithium atoms compared to the cubic phase, which enhanced the cycling performance.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2013/ancac3.2013.7.issue-10/nn403674z/production/images/medium/nn-2013-03674z_0009.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn403674z'>ACS Electronic Supporting Info</A></P>

Effects of Humidity on the Friction Coefficient of Diamond-Like Carbon (DLC) Coating

Sang G. Kim,Yong K. Cho,Woo S. Jang,Sung W. Kim,Saito Nagahiro,Osamu Takai 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.54 No.3

A diamond-like Carbon (DLC) coating has been known to be a good tribological problem solver due to its low friction characteristics and high hardness. The friction coefficient values shown in the literature surveyed differ from the authors' due to different test conditions. When we plot these results and our own with the variable of humidity, the friction coefficient decreases with increasing environmental humidity. By using contact angle measurements to study the interface properties of these coatings, we conclude that this change comes from the hydrophilic and the hydrophobic properties of the surface and the eventual change of the wear mode. DLC films were deposited on SKD11 steel by using pulsed (DC PECVD) (a-C:H, hydrogenated DLC, Si-containing DLC) and amorphous carbon filtered arc DLC (a-C, non-hydrogenated DLC). Deposited DLCs were tested according to humidity by using a tribometer. We used a SUJ2 (JIS standard) steel ball bearing for the counterpart of wear test. X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and surface roughness testers were used for surface analysis of the DLC and the wear trace. The Raman spectra of the films showed that the carbon bonding structures changed according to the I(D)/I(G) intensity ratio for the wear trace at severe wear conditions. In normal humidity, 30~85 % RH, the DLC had a friction coefficient lower than it did in 5 % RH. In this case, the Si-containing hydrogenated DLC definitely had the lowest friction coefficient. Eventually, it also had the lowest contact angle, as expected. When we investigated two different kinds of DLCs in terms of hydrogen content, we observed the same effect of relative humidity on friction behavior. A diamond-like Carbon (DLC) coating has been known to be a good tribological problem solver due to its low friction characteristics and high hardness. The friction coefficient values shown in the literature surveyed differ from the authors' due to different test conditions. When we plot these results and our own with the variable of humidity, the friction coefficient decreases with increasing environmental humidity. By using contact angle measurements to study the interface properties of these coatings, we conclude that this change comes from the hydrophilic and the hydrophobic properties of the surface and the eventual change of the wear mode. DLC films were deposited on SKD11 steel by using pulsed (DC PECVD) (a-C:H, hydrogenated DLC, Si-containing DLC) and amorphous carbon filtered arc DLC (a-C, non-hydrogenated DLC). Deposited DLCs were tested according to humidity by using a tribometer. We used a SUJ2 (JIS standard) steel ball bearing for the counterpart of wear test. X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and surface roughness testers were used for surface analysis of the DLC and the wear trace. The Raman spectra of the films showed that the carbon bonding structures changed according to the I(D)/I(G) intensity ratio for the wear trace at severe wear conditions. In normal humidity, 30~85 % RH, the DLC had a friction coefficient lower than it did in 5 % RH. In this case, the Si-containing hydrogenated DLC definitely had the lowest friction coefficient. Eventually, it also had the lowest contact angle, as expected. When we investigated two different kinds of DLCs in terms of hydrogen content, we observed the same effect of relative humidity on friction behavior.

Effect of lymphadenectomy in colorectal cancer with isolated synchronous Para-Aortic Lymph node metastasis

Sung Chul LEE,Hee Cheol KIM,Woo Yong LEE,Seong Hyeon YUN,Yong Beom CHO,Jung Wook HUH,Yoon Ah PARK,Jung Kyong SHIN 대한외과학회 2019 대한외과학회 학술대회 초록집 Vol.2019 No.10