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121.
Kyung Seob Lim Jun-Kyu Park Myung Ho Jeong Jae-Woon Nah Dae Sung Park Jong Min Kim Jung Ha Kim So Youn Lee Eun Jae Jang Suyoung Jang Hyun Kuk Kim Doo Sun Sim Keun-Ho Park Young Joon Hong Youngkeun Ahn Jung Chaee Kang 《Journal of materials science. Materials in medicine》2016,27(4):66
The aim of this study was to evaluate antiproliferative sirolimus- and antioxidative alpha-lipoic acid (ALA)-eluting stents using biodegradable polymer [poly-l-lactic acid (PLA)] in a porcine coronary overstretch restenosis model. Forty coronary arteries of 20 pigs were randomized into four groups in which the coronary arteries had a bare metal stent (BMS, n = 10), ALA-eluting stent with PLA (AES, n = 10), sirolimus-eluting stent with PLA (SES, n = 10), or sirolimus- and ALA-eluting stent with PLA (SAS, n = 10). A histopathological analysis was performed 28 days after the stenting. The ALA and sirolimus released slowly over 30 days. There were no significant differences between groups in the injury or inflammation score; however, there were significant differences in the percent area of stenosis (56.2 ± 11.78 % in BMS vs. 51.5 ± 12.20 % in AES vs. 34.7 ± 7.23 % in SES vs. 28.7 ± 7.30 % in SAS, P < 0.0001) and fibrin score [1.0 (range 1.0–1.0) in BMS vs. 1.0 (range 1.0–1.0) in AES vs. 2.0 (range 2.0–2.0) in SES vs. 2.0 (range 2.0–2.0) in SAS, P < 0.0001] between the four groups. The percent area of stenosis based on micro-computed tomography corresponded with the restenosis rates based on histopathological stenosis in different proportions in the four groups (54.8 ± 7.88 % in BMS vs. 50.4 ± 14.87 % in AES vs. 34.5 ± 7.22 % in SES vs. 28.9 ± 7.22 % in SAS, P < 0.05). SAS showed a better neointimal inhibitory effect than BMS, AES, and SES at 1 month after stenting in a porcine coronary restenosis model. Therefore, SAS with PLA can be a useful drug combination for coronary stent coating to suppress neointimal hyperplasia. 相似文献
122.
Kwang-Jun Oh Young-Bong Ko Sagar Jaiswal In-Cheul Whang 《Journal of materials science. Materials in medicine》2016,27(12):179
The purpose of this study was to compare the osteoconductivity, and absorbability of hydroxyapatite or beta-tricalcium phosphate in clinical scenario of opening wedge high tibial osteotomy Total 41 knees of 40 patients with follow up period of more than 1 year were enrolled. These patients were divided into two groups, Group I (22 knees, 21 patients) used hydroxyapatite and Group II (19 knees, 19 patients) used beta-tricalcium phosphate as a substitute in the opening gap. According to proven method, the osteoconductivity was assessed radiographically by the extent of new bone formation at osteotomy space and absorbability was evaluated by measuring the area occupied by substitute at immediate postoperative, postoperative 6 months and 1 year. Regarding preoperative demographic data, no significant differences were found between two groups. No statistically significant differences were found between two groups regarding lower limb alignment (mechanical femorotibial angle, weight-bearing line%) and posterior tibial slope at postoperative and final follow up radiographs. Concerning the osteoconductivity, there were no significant differences between two groups in any zone. However, the absorption rate was significantly greater in the Group II than in Group I at 6 months (Group I: 13.7?±?6.8, group II: 35.3?±?15.8, P?=?0.001) and 1 year (Group I: 24.2?±?6.3, Group II: 49.6?±?14.3, P?<?0.0001). The complications related to bone substitutes were not observed. Both hydroxyapatite and beta-tricalcium phosphate showed satisfactory gap healing without complications and can be successfully used as alternative healing materials in opening wedge high tibial osteotomy. Our study showed that beta-tricalcium phosphate has superior absorbability than hydroxyapatite. But osteoconductivity showed no significant difference. 相似文献
123.
Raman Scattering Mapping: Sensitive and Reproducible Immunoassay of Multiple Mycotoxins Using Surface‐Enhanced Raman Scattering Mapping on 3D Plasmonic Nanopillar Arrays (Small 39/2018) 下载免费PDF全文
124.
CY Ko EE Whang R Karamanoukian WP Longmire DW McFadden 《Canadian Metallurgical Quarterly》1998,133(8):900-905
OBJECTIVES: To characterize the career choices and developments made by leading senior surgeons in this country and to examine hypothetically whether application of a short tracking program would have hindered their career decisions. DESIGN: A survey pertaining to each surgeon's career, decisions, and opinions concerning surgical training. SETTING AND PARTICIPANTS: Senior surgeons of regional and national surgical societies. MAIN OUTCOME MEASURE: Survey responses. RESULTS: A total of 352 surveys (41.4%) were received. Respondents answered that the most common reasons for choosing a specialty were role models or mentors (56%), research (51%), and available patient population (23%). The 2 most common stages in a career at which the respondents became interested in a specialty, or an area of expertise, were at the junior residency level (when the specialty was chosen) and at the assistant professor level (when a more specific topic within the specialty was chosen). The most common stage at which the group believed they acquired their expertise was also at the assistant professor level. Seventy-one percent of respondents believed broad training was superior to a short tracking system, although none had participated in shortened surgical training. CONCLUSIONS: Most leading senior surgeons in this country still believe that broad surgical training is superior and should be maintained. Because career specialties in this surveyed group were generally chosen in early residency, a hypothetical application of the short tracking system would have still allowed for these important decisions to be made. Also, it seems likely that specialty and career development would not have been hindered because "expertization" mostly occurred after training was completed. Regardless of training method, a role model or mentor seems most important in career choices and developments. 相似文献
125.
Gregory Gutin Eun Jung Kim Matthias Mnich Anders Yeo 《Journal of Computer and System Sciences》2010,76(8):872-878
We study ordinal embedding relaxations in the realm of parameterized complexity. We prove the existence of a quadratic kernel for the Betweenness problem parameterized above its tight lower bound, which is stated as follows. For a set V of variables and set C of constraints “vi is between vj and vk”, decide whether there is a bijection from V to the set {1,…,|V|} satisfying at least |C|/3+κ of the constraints in C. Our result solves an open problem attributed to Benny Chor in Niedermeier's monograph “Invitation to Fixed-Parameter Algorithms”. The betweenness problem is of interest in molecular biology. An approach developed in this paper can be used to determine parameterized complexity of a number of other optimization problems on permutations parameterized above or below tight bounds. 相似文献
126.
This paper proposes a dispatching rule that guarantees a predetermined minimum quality level for non-identical parallel machines with multiple product types. Manufacturers are focusing on improving the overall quality of their products, as the demand for top quality products is increasing. Such changes increase the possibility of neglecting another crucial factor in manufacturing schedules, namely due date. Traditionally, jobs are dispatched with the focus on meeting due dates. That is, jobs are assigned to machines without consideration of product quality. This approach opens the possibility of manufacturing poor quality products. Realizing the shortcomings of the existing dispatching rules, manufacturers are tempted to dispatch jobs with the objective of maximizing product quality. With such an attempt, jobs are likely to be assigned to high performance machines only. In turn, waiting times will increase and job delays are inevitable. This research proposes a dispatching rule that satisfies both criteria, reducing due date delays, while ensuring a predefined product quality level. A quality index is introduced to standardize various product qualities. The index is used to ensure a predetermined quality level, whilst minimizing product delays. Simulations compare various dispatch methods, evaluating them based on mean tardiness and product quality. 相似文献
127.
Urban environments possess many regularities which can be efficiently exploited for 3D dense reconstruction from multiple
widely separated views. We present an approach utilizing properties of piecewise planarity and restricted number of plane
orientations to suppress reconstruction and matching ambiguities causing failures of standard dense stereo methods. We formulate
the problem of the 3D reconstruction in MRF framework built on an image pre-segmented into superpixels. Using this representation,
we propose novel photometric and superpixel boundary consistency terms explicitly derived from superpixels and show that they
overcome many difficulties of standard pixel-based formulations and handle favorably problematic scenarios containing many
repetitive structures and no or low textured regions. We demonstrate our approach on several wide-baseline scenes demonstrating
superior performance compared to previously proposed methods. 相似文献
128.
Sang‐Hee Ko Park Min‐Ki Ryu Sung‐Min Yoon Shinhyuk Yang Chi‐Sun Hwang Jae‐Hong Jeon 《Journal of the Society for Information Display》2010,18(10):779-788
Abstract— The stability of oxide TFTs has been the main focus of this research and is probably the most crucial requirement for the successful application to flat‐panel displays. Although the high Fermi level of oxide semiconductors makes TFTs basically stable under electrical stress, the device reliability under diverse variations of electrical stress is affected by materials such as active semiconductors and gate insulators, processes for the formation of back/front channels and passivation layers, and device configurations among other things. How these factors affect the device reliability have been investigated and a review of the stability is presented. In addition, several categories of the light instability of oxide TFTs is presented and the origin is discussed. 相似文献
129.
Jong Myoung Ko Choonjong Kwak Youngho Cho Chang Ouk Kim 《Expert systems with applications》2011,38(3):1583-1590
The Radio Frequency Identification (RFID) technology is gradually being adopted and deployed for product flow management in the supply chain. In order to track RFID-tagged products efficiently in the RFID-enabled, large-scale supply chain, this paper first presents the design of a product tracking system that can collaborate with the EPC Network, a suite of network services for RFID data management in the supply chain. Next, we explain a product monitoring procedure that is performed by comparing the actual path of a product with its planned path. Finally, we develop an adaptive product search algorithm based on a reinforcement learning technique to efficiently locate a product deviated from its planned path. Experiment results are provided to show the performance of the search algorithm. 相似文献
130.
Hyo-Heon Ko Jun-Seok Kim Jihyun Kim Jun-Geol Baek Sung-Shick Kim 《Expert systems with applications》2011,38(6):6759-6767
This paper proposes an efficient control method to minimize process error and to reduce process variance in semiconductor manufacturing. The photolithography (photo) process forms a complex semiconductor circuit and is important for quality. Obstacles to the process include the facility itself, vibration, wear and tear, product/process changes and environmental influences. Control methodologies being currently used to address these issues often amplify the variation of the process by failing to perform adequate process control. Therefore, this paper proposes an effective process control method to reduce process variance by quickly detecting and identifying process disturbances and accurately reflecting the degree of change to process control. This study proposes dynamic deadband control that uses a region (band) to detect the status of a process change. It adjusts the process control based on the changes detected. In this research, the semiconductor manufacturing company is supported to perform control that is more precise and reduces fluctuations by producing products of uniform quality. In addition, it can contribute to yield due to the quality incentive and increased process control of semiconductor manufacturing. 相似文献