• Animal Bioscience
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• 제35권9호
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• pp.1340-1350
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• 2022

Objective: Luxi Black Head sheep (LBH) is the first crossbreed specialized for meat production and was developed by crossbreeding Black Head Dorper sheep (DP) and Small Tailed Han sheep (STH) in the farming areas of northern China. Research on the genomic variations and selection signatures of LBH caused by continuous artificial selection is of great significance for identifying the genetic mechanisms of important traits of sheep and for the continuous breeding of LBH. Methods: We explored the genetic relationships of LBH, DP, and several Mongolian sheep breeds by constructing phylogenetic tree, principal component analysis and linkage disequilibrium analysis. In addition, we analysed 29 whole genomes of sheep. The genome-wide selection signatures have been scanned with four methods: heterozygosity (H_P), fixation index (F_ST), cross-population extended haplotype homozygosity (XP-EHH) and the nucleotide diversity (𝜃_π) ratio. Results: The genetic relationships analysis showed that LBH appeared to be an independent cluster closer to DP. The candidate signatures of positive selection in sheep genome revealed candidate genes for developmental process (HoxA gene cluster, BCL2L11, TSHR), immunity (CXCL6, CXCL1, SKAP2, PTK6, MST1R), growth (PDGFD, FGF18, SRF, SOCS2), and reproduction (BCAS3, TRIM24, ASTL, FNDC3A). Moreover, two signalling pathways closely related to reproduction, the thyroid hormone signalling pathway and the oxytocin signalling pathway, were detected. Conclusion: The selective sweep analysis of LBH genome revealed candidate genes and signalling pathways associated with developmental process, immunity, growth, and reproduction. Our findings provide a valuable resource for sheep breeding and insight into the mechanisms of artificial selection.

• 생명과학회지
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• 제8권5호
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• pp.582-588
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• 1998

징거미 새우의 정소는 한 쌍의 관으로 되어 있고, 정소의 중앙 후반부에서 기원된 수정관은 제 5보각의 기부에 위치한 생식공까지 연결되어 있다. 수정관은 기부, 나선부, 말단부, 사정관으로 구분되었다. 수정관은 simple columnar ephithelium, high columnar ephithelium, 종주근과 환상근으로 이루어져 있다. AG는 수정관의 말단부에서 사정관에 걸쳐 위치하고 있다. AG의 형태는 불규칙한 세포 덩어리로 되어져 있고, hematoxyline에 약하게 염색되는 염색질과 둥글고 커다란 핵을 가진다. 핵질과 세포질은 염기성 핵막을 경계로 쉽게 구분되나, 세포질과 세포질사이의 경계는 그 구별이 어렵다. 암컷의 복판에 부착된 정포는 호산성기질, 호염기성기질 그리고 호염기성기질에 싸여있는 한 쌍의 정자덩어리로 구성되어 있다. 성숙정자는 압정형태이고, 두부는 가운데 부분이 약간 오목한 원반형이고, 미부는 두부 중앙부 하단의 약간 볼록한 부분에서 연장된 하나의 spike를 이루고 있다. 정자의 크기는 두부의 직경이 약 8 $\mu$m, 미부의 길이가 약 10 $\mu$m였다.

• 통상정보연구
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• 제6권3호
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• pp.63-79
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• 2004

Peer-to-peer(P2P) has potential strength and possible factors which enable it to develop toward a new business by supplementing the limitation of the existing central server-type network. In various business sectors, various attempts have already been made to apply P2P. The computing power which was possible to be formed through peer-to-peer networking will become a powerful tools for expanding toward new business area depending the utilization methods by sector. Although the technology-centric P2P concept is a major interest now, its development direction will head toward service-centric P2P concept for satisfying desires of end-users(individual peers) for reliable contents and improving their purchasing convenience. But the solution requisites should be solved for the efficient application of P2P to business such as the establishment of and supplement for the industrial standard and legal system for P2P, the enhancement of peers recognition of P2P. Presently e-commerce using P2P is being implemented by a few enterprises locally by means of B2C. But if many enterprises enter this type of e-commerce, and the standardization of peer programmes, goods and documents is made, it will be able to be extended to B2B. Also it seems that it can be utilized in international transactions as well as in domestic transactions. So there is much room for the application of P2P to be extended further. Also there has been presented the necessity for related industries to support their work with theories and for academic studies to be made actively to set the direction of its development. It is hoped that multi-angled and in-depth studies on the utilization of P2P and various attempts to application of it to business be made on the basis of this study. For the development of P2P, continuous study and attempts are needed. The field of P2Ps application is very large and it will become a powerful tool, depending upon its application methods.

• 한국환경과학회지
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• 제24권12호
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• pp.1551-1558
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• 2015

In Korea, many drinking water treatment plants (DWTPs) have introduced and are going to introduce biological activated carbon (BAC) process to treated dissolved organic matter (DOM) in water which are difficult to control by conventional water treatment processes. Even though more decade have passed since introduced BAC in Korea, most of BAC operating method was followed to the modified sand filter operating manuals. In case of BAC backwashing, many DWTPs set the periods of backwashing about 3~5 days. In this study, we have collected data to set the proper BAC backwashing periods from both pilot-plant and real DWTPs. We had measured heterotrophic plate count (HPC), turbidity, water temperature, dissolved organic carbon (DOC) and headloss from just after backwashing to the next backwashing time for two years. Considering water quality factors, the BAC run time from backwashing to the next backwashing could extend more 30 days without water quality deterioration if the head loss do not reach the limited level which depends on each BAC facilities' condition. It means the BAC treated water could be saved in the proportion of extended the backwashing period to the existing backwashing period.

• Steel and Composite Structures
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• 제18권6호
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• pp.1423-1450
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• 2015

The paper presents the details and results of an experimental study on bolted end-plate joints of industrial type steel building frames. The investigated joints are commonly used in Lindab-Astron industrial buildings and are optimized for manufacturing, erection and durability. The aim of the research was to provide an experimental background for the design model development by studying load-bearing capacity of joints, bolt force distribution, and end-plate deformations. Because of the special joint details, (i.e., joints with four bolts in one bolt-row and HammerHead arrangements), the Eurocode 3 standardized component model had to be improved and extended. The experimental programme included six different end-plate and bolt arrangements and covered sixteen specimens. The steel grade of test specimens was S355, the bolt diameter M20, whereas the bolt grade was 8.8 and 10.9 for the two series. The end-plate thickness varied between 12 mm and 24 mm. The specimens were investigated under pure bending conditions using a four-point-bending test arrangement. In all tests the typical displacements and the bolt force distribution were measured. The end-plate plastic deformations were measured after the tests by an automatic measuring device. The measured data were presented and evaluated by the moment-bolt-row force and moment-distance from centre of compression diagrams and by the deformed end-plate surfaces. From the results the typical failure modes and the joint behaviour were specified and presented. Furthermore the influence of the end-plate thickness and the pretension of the bolts on the behaviour of bolted joints were analysed.

• 한국유체기계학회 논문집
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• 제19권5호
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• pp.50-60
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• 2016

A design methodology of the modeled test facility to conserve an injection performance of a passive safety injection system is proposed. This safety injection system is composed of a core makeup tank and a safety injection tank. Individual tanks are connected with pressure balance line on the top side and injection line on the bottom side. It is important to conserve the scaled initial injection flow rate and total injection time since this system can be operated by small gravity head without any active pumps. Differential pressure distribution of the injection line induced by the gravity head is determined by the vertical length and elevation of each tank. However, the total injection time is adjustable by the flow resistance coefficient of the injection line. The scaling methodology for the tank and flow resistance coefficient is suggested. A key point of this test facility design is a scaling analysis for the flow resistance coefficient. The scaling analysis proposed on this paper is based on the volume scaling law with the same vertical length to the prototype and can be extended to a model with a reduced vertical length. A set of passive injection test were performed for the tanks with the same volume and the different length. The test results on the initial flow rate and total injection time showed the almost same injection characteristics and they were in good agreement with the design values.

• Applied Microscopy
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• 제35권4호
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• pp.42-54
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• 2005

본 연구는 무당개구리과 (Discoglossidae)의 무당개구리(Bombina orientalis) 정자의 형태적 특징을 광학현미경과 주사 및 투과 전자현미경으로 관찰하였다. 정자두부는 전 후방의 끝이 뾰족하고 다소 유연성을 갖는 초생달 혹은 버들 잎 모양의 특이한 구조를 취하고 있었다. 핵은 전 후방이 가늘고, 중앙 부분은 굵은 원뿔형이었다. 염색질은 완전하게 농축되어 있지 않고, 마치 널빤지를 겹쳐 놓은 듯한 지붕모양과 같은 형태로 불규칙하게 배열되어져 있었다. 핵 내에는 불규칙한 형태의 nuclear lacunae들이 흩어져 있었다. 정자경부와 중편부는 발달 되어 있지 않았다. 편모는 9+2 구조의 axoneme, axial rod 그리고 undulating membrane을 가지고 있었다. 미토콘드리아들은 핵의 상단부를 둘러싸고 있는 protoplasmic bead내에만 국한되어 존재하고 있었다. 특히, 본 연구에서 핵의 전방부에서 중앙 부위로 주행하는 nuclear rod는 섬유성 다발로 구성되었으며, 마치 사람의 속눈썹 모양과 같은 형태를 취하며, 핵의 2/3까지 뻗쳐져 있었다.

• Clinics in Shoulder and Elbow
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• 제1권2호
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• pp.154-159
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• 1998

Medial dislocation of the long head of the biceps brachii is a rare condition that usually occurs in association with tears of the subscapularis, chronic impingement, capsular defects or a fracture of the lesser tuberosity. Less commonly, a biceps tendon dislocation may occur after an acute traumatic event. Following a dislocation, the biceps tendon will assume either an intra- or extra-articular position depending on whether or not the subscapularis tendon detaches from its humeral insertion. Magnetic resonance imaging has been found to provide valuable information concerning the location of the biceps tendon and the integrity of the subscapularis tendon. We present a patient with a traumatic dislocation of the biceps brachii tendon in which the diagnosis remained elusive for an extended period of time. In this case, he was evaluated using MRI and reconstruction was performed by restoring the tendon to its anatomical position.

• 대한두경부종양학회지
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• 제15권1호
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• pp.40-45
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• 1999

Objectives: Maxillary cancer is notorious for its poor prognosis because it is usually detected lately and the majority of patients have advanced disease. Especially when the cancer extended to infratemporal fossa or pterygopalatine fossa it is very difficult to remove all the involved structure by conventional maxillectomy. In these cases we have used radical maxillectomy through lateral approach. We tried to figure out the clinical significance of this procedure. Material and Methods: This study retrospectively analyzed 23 patients with squamous cell carcinoma of the maxillary sinus who underwent surgical treatment for cure. Among them 17 patients(group A) were treated with initial surgery and 6 patients(group B) underwent salvage surgery after radiotherpy. Radical maxillectomy was performed in 12 patients and conventional total maxillectomy in 11 patients. Results: In group A, 3 out of 9 total maxillectomy case and none of 8 radical maxillectomy case were recurred. In group B one patient died of postoperative complication and among the other 5 patients only one out of 3 radical maxillectomy was salvaged and 2 total maxillectomy cases were died of intercurrent disease. Conclusion: Wide surgical dissection of pterygopalatine fossa and infratemporal fossa may improve the survival rate in patients with posterior wall invasion of maxillary sinus.

• 대한두경부종양학회지
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• 제2권1호
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• pp.13-22
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• 1986

Nasal fossae 의 암이란 비강과 부비동들에서 발생하는 것으로서 환자를 가장 괴롭히며 또한 가장 믿을수 없는 악성종양들중의 하나이다. 비록 본 예수병원 암환자 등록부에 의하면 전 암환자의 2.2% 발생빈도로서 주요한 발생빈도를 보이지는 않지만, 이 부위의 암을 치유하는데는 세심하고 철저한 모든 진단적 검사와 과감한 외과 및 치료방사선의 병합치료가 요구된다. 저자들은 지난 22 년간 비강 및 부비동 (Nasal fossae) 에서 발생한 원발성 악성종양중 치유목적의 근치수술을 시행한 68 예를 임상고찰 하였다. 근치수술을 시행했던 68 예중 91% 에서 제 3 병기 또는 4 병기의 진행된 경우 이었다. 외과적 수술은 한예의 사골동 (篩骨洞) 종양적출술 및 부분상악동(上顎洞)절제술 한 예를 제외한 66 예 모두에서 전상악동(全上顎洞)절제술 (total maxillectomy) 또는 확장 전상악동(全上顎洞)절제술 (extended total maxillectomy) 을 시 하였다. 저자들은 역학적(疫學的), 병리학적(病理學的), 병기(病期) 및 치료, 재발율과 생존율들을 분석 고찰하였으며 3가지 치료형태를 서로 비교하였다. 즉 수술만 시행한 군, 수술전 방사선 치료 및 수술병합군, 수술과 수술후 방사선치료 병합 군으로 나눴다. 저자들의 예비적 (preliminary) 관찰 결과는 2 년간 무병생존율 (disease-free 2-year survival) 만을 볼때, 수술만 시행한 군에서 40%로써 통계학적으로는 가장 좋았으나 실제는 수술만 시행한 군에서는 단지 40%만이 제 4 병기(病期)의 진행된 경우였으나 수술전 방사선치료 또는 수술후 방사선치료등의 병합치료에서는 제 4 병기(病期)의 진행된 상태가 무려 60 %나 되었다. 전체적인 재발율 (Overall recurrence rate) 은 68.2%로써 무서울 정도로 높았으며 전체적인 2 년 무병율은 23.7%였다. 저자들은 이 분야에서 실패의 원인분석과 치료방법의 선택등에 대한 지침을 제시하고저 한다.