• Title/Summary/Keyword: partial changes

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Animal Models of Alzheimer's Dementia (알쯔하이머 치매의 동물모형)

  • Woo, Sung-Il
    • Korean Journal of Biological Psychiatry
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    • v.6 no.2
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    • pp.149-152
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    • 1999
  • Transgenic mice models of Alzheimer's disease were produced by overexpressing APP(amyloid precursor protein) mutant and presenilin mutant genes using the promotors that induced neuronal expression. The neuropathologies, electrophysiological changes and behavioral changes that were demonstrated in these transgenic mice models were amyloid changes, gliotic changes, A-beta increases, deficit in LTP(long-term potentiation) and behavioral changes. Some or all of the above changes were found in each transgenic mice model. These models generally showed amyloid neuropathology but they usually lacked the neurofibrillary tangles. So, they can be regarded as partial models of Alzheimer's disease. The development of them is undoubtedly the great progress toward future research.

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The Effects of Partial Vibration on Tibia of Osteoporosis Induced Rat (골다공증이 유발된 쥐 정강이뼈에 적용한 부분 진동자극 효과)

  • Park, Ji-Hyung;Seo, Dong-Hyun;Jung, Young-Jin;Ko, Chang-Yong;Kim, Han-Sung
    • Journal of the Korean Society for Precision Engineering
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    • v.29 no.5
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    • pp.578-583
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    • 2012
  • The pharmacological therapies and whole body vibration as non-pharmacological therapies were known to have adverse side effects. Therefore, partial stimulation was suggested and its effects were evaluated. This study aimed to evaluate the site-specific effects of partial stimulator for treatment of osteoporosis induced by estrogen deficiency. Sixteen virginal Sprague-Dawley rats (12 weeks old) were divided into 2 groups(no stimulation, stimulation groups). All rats were ovariectomised to induce osteoporosis. After 3 weeks of operation, the right tibiae in rats of stimulation group (frequency: 10Hz, cycle: 1500, strain on bone surface: $2000{\mu}{\varepsilon}$) were stimulated perpendicularly at right tibia by using partial stimulator for 6 weeks (3days/week). The right tibiae in rats were scanned, before stimulation (0 week) and at 6 weeks after stimulation by using in-vivo micro computed tomography. For investigation of changes in morphological characteristics, structural parameters were measured and calculated. At 6 weeks the morphological characteristics (relative value) in stimulation group were significantly enhanced than those in no stimulation group (p<0.05). In this study, we find that after 6 weeks of partial stimulation, the morphological characteristics of tibia trabecular bone were enhanced. Thus, we concluded that partial stimulation could be used to treat osteoporosis.

Study on vibration energy characteristics of vehicle-track-viaduct coupling system considering partial contact loss beneath track slab

  • Liu, Linya;Zuo, Zhiyuan;Zhou, Qinyue;Qin, Jialiang;Liu, Quanmin
    • Structural Engineering and Mechanics
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    • v.75 no.4
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    • pp.497-506
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    • 2020
  • CA mortar layer disengagement will give rise to the overall structural changes of the track and variation in the vibration form of the ballastless track. By establishing a vehicle-track-viaduct coupling analysis and calculation model, it is possible to analyze the CRTS-I type track structure vibration response while the track slab is disengaging with the power flow evaluation method, to compare the two disengaging types, namely partial contact loss at one edge beneath track slab and partial contact loss at midpoint beneath track slab. It can also study how the length of disengaging influences the track structures vibration power. It is showed that when the partial contact loss beneath track slab, and the relative vibration energy level between the rail and the track slab increases significantly within [10, 200]Hz with the same disengaging length, the partial contact loss at one edge beneath track slab has more prominent influence on the vibration power than the partial contact loss at midpoint beneath track slab. With the increase of disengaging length, the relative vibration energy level of the track slab grows sharply, but it will change significantly when it reaches 1.56 m. Little effect will be caused by the relative vibration energy level of the viaduct. The partial contact loss beneath the track slab will cause more power distribution and transmission between the trail and track slab, and will then affect the service life of the rail and track slab.

AN EXPERIMENTAL STUDY ON THE MANDIBULAR GROWTH BY THE PARTIAL GLOSSECTOMY OF THE RATS (백서 부분적 설절제가 하악골 성장에 미치는 영향에 관한 실험적 연구)

  • Hyun, Sug-Hwan;Kim, Kwang-Won
    • The korean journal of orthodontics
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    • v.25 no.5 s.52
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    • pp.567-575
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    • 1995
  • The purpose of this study was to investigate the effect of the partial glossectomy on the mandibular growth of growing rats. Thirty one Sprague-Dawley rats four weeks old were divided into two groupes : the first group served as the control and the second group was partially excised in the tongue of the rats. The experimental animals were sacrificed at 4 and 8 weeks after partial glossectomy. The changes of the rat mandibular growth following partial glossectomy were observed biometrically from dry bone specimens. The findings were as follows : 1. Partial glossectomy of growing rat produced inhibitory effects on the growth of the mandible and did not change the original shape of the mandible. 2. Among the factors affecting mandibular growth, the presence of the proper tongue size was essential. 3. Partial glossectomy of the growing rats could not change general growth of the rats whole bodies.

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A Study on Partial Load Performance of Absorption Type Heat Pump for Waste Heat Recovery of Closed Cooling Water (기기냉각수 폐열회수용 흡수식 히트펌프의 부분부하 성능에 관한 연구)

  • Park, Byungchul;Kim, Taehyeong;Kim, Kwangsu
    • Journal of Energy Engineering
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    • v.28 no.2
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    • pp.47-54
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    • 2019
  • As absorption type heat pump for waste heat recovery is installed in combined cycle power plant for Energy Service Company, performance test is implemented to confirm the operation data on partial load. The operation data changes according to the heat pump operation on partial load are as follows. Total heat output increases, because waste heat of closed cooling water and a portion of LP steam from HRSG is supplied. But electric power output of steam turbine is reduced, because LP steam to steam turbine is reduced. And heat output from HP district heater and LP district heater is reduced, because HP turbine exhaust steam to HP district heater and LP district heater is reduced. On partial load operation, turbine output reduction is higher than the base load operation. Therefore, on partial load, heat pump should be operated in consideration of the heat output increase and electric power output reduction.

Partial Arytenoidectomy in a Horse

  • Seyoung Lee;Eun-bee Lee;Kyung-won Park;Hyohoon Jeong;Jong-pil Seo
    • Journal of Veterinary Clinics
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    • v.39 no.6
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    • pp.400-404
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    • 2022
  • A 3-year-old Thoroughbred gelding presented with left laryngeal hemiplegia with a history of laryngoplasty (tie-back surgery) failure. Postoperative endoscopy revealed no abduction or no inflammatory changes in the left arytenoid cartilage. The owner opted for the horse to undergo partial arytenoidectomy due to failed laryngoplasty. A tracheostomy tube was intubated through a mid-cervical tracheotomy to secure the airway under general anesthesia, and; laryngotomy was performed to access the arytenoid cartilage in dorsal recumbency. A partial arytenoidectomy was performed with endoscopic assistance through the left nostril, and the left arytenoid cartilage was removed, excluding the muscular process. Antibiotic and anti-inflammatory agents were administered postoperatively, and the incision site was cleaned using normal saline and antibiotic ointment twice daily. On the 12th postoperative day, endoscopy revealed redundant corniculate process mucosa at the surgical site, which was removed using rongeur forceps directly through the previous laryngotomy incision. The horse showed no significant complications during the hospitalization. Two months after surgery, the surgical site reportedly recovered with no evidence of granulation tissue. The horse returned to training and racing 3 and 7 months postoperatively, respectively. This is the first case report of a partial arytenoidectomy in a horse in South Korea. In this case, the horse returned to training after partial arytenoidectomy without significant complications, indicating that partial arytenoidectomy could be beneficial for failed laryngoplasty.

A Study on Behavior Pattern and Physiological Changes during Bathing and Showering (목욕 및 샤워시 행동패턴 및 생리적 변화에 대한 연구)

  • Jeong W.W.;Rhee K.;Park K.R.;Chun K.J.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.10a
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    • pp.256-259
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    • 2005
  • Analysis of behavior pattern and thermal response during bathing and showering provides important fundamental data when developing an automatic bathing/showering system. The behavior pattern and physiological changes during bathing/showering were measured und analyzed for the aged male group. We recorded the volunteers showering at front, back, left and right view using four CCTV cameras in order to study the behavior pattern during showering. The photographic data were analyzed by counting the frequencies of body contact and identifying zones where hands could reach. In order to study the thermal response, we measured the blood pressure (B.P), heart rate (H.R), body temperature (B.T.), breathing rate (B.R) for the different water temperatures and the locations of immersion for the young and old age groups. The results showed that the frequencies of body contacts were varied for different body sections. Also there were some body sections where hands could not be reached because of reduced pliability and muscular strength of the aged group. But we observed rather uniform body contact frequencies when a towel was used. In partial immersion bath experiments, we observed the changes of B.P. H.R and B.T in the case of young and old age groups, and the changes were more significant in the young age group.

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Response Force Distribution Factors of Members and Mutuality of Response Forces between Members (부재응력분포계수와 부재간 응력 상관성)

  • 김치경;이시은;홍건호
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2004.10a
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    • pp.363-370
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    • 2004
  • This Paper presents the response force distribution factor(RDF) and its application to recalculation of member forces in case of partial changes of structures. Using RDF, the mutuality of response forces between members can be estimated. The reanalysis technique recalculates directly any displacement or member force under consideration in real time without a full reanalysis in spite of local changes in member stiffness or connectivity using RDF. It is expected that RDF and the reanalysis technique can be used to develop efficient analysis techniques for tall buildings.

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MPEG-1 Video Scene Change Detection Using Horizontal and Vertical Blocks (수평과 수직 블록을 이용한 MPEG-1 비디오 장면전환 검출)

  • Lee, Min-Seop;An, Byeong-Cheol
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.2S
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    • pp.629-637
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    • 2000
  • The content-based information retrieval for a multimedia database uses feature information extracted from the compressed videos. This paper presents an effective method to detect scene changes from compressed videos. Scene changes are detected with DC values of DCT coefficients in MPEG-1 encoded video sequences. Instead of decoding full frames. partial macroblocks of each frame, horizontal and vertical macroblocks, are decoded to detect scene changes. This method detects abrupt scene changes by decoding minimal number of blocks and saves a lot of computation time. The performance of the proposed algorithm is analyzed based on the precision and the recall. The experimental results show the effectiveness in computation time and detection rate to detect scene changes of various MPEG-1 video streams.

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Effect of O2 Partial Pressure on AlOx Thin Films Prepared by Reactive Ion Beam Sputtering Deposition

  • Seong, Jin-Wook;Yoon, Ki-Hyun;Kim, Ki-Hwan;Beag, Young-Whoan;Koh, Seok-Keun
    • Journal of the Korean Ceramic Society
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    • v.41 no.5
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    • pp.364-369
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    • 2004
  • The barrier and optical properties of AlO$_{x}$ thin films on polycarbonate deposited by Reactive Ion Beam Sputtering (RIBS) were investigated at different oxygen partial pressure. We measured the deposition rate of AlO$_{x}$ thin films. As the oxygen partial pres-sure increased, the deposition rate increased then decreased. The changes of deposition rate are associated with the properties of deposited films. The properties of deposited AlO$_{x}$ thin films were studied using X-ray Photoelectron Spectroscopy (XPS), Scan-ning Electron Microscopy (SEM), and Atomic Force Microscopy (AFM). Optimum deposition parameters were found for fabricat-ing aluminum oxide thin films with high optical transparency for visible light and low Oxygen Transmission Rate (OTR). The optical transmittance of AlO$_{x}$ thin film deposited on polycarbonate (PC) showed the same value of bare PC.bare PC.