• Toxicological Research
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• 제29권1호
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• pp.1-6
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• 2013

The process of drug discovery and development requires substantial resources and time. The drug industry has tried to reduce costs by conducting appropriate animal studies together with molecular biological and genetic analyses. Basic science research has been limited to in vitro studies of cellular processes and ex vivo tissue examination using suitable animal models of disease. However, in the past two decades new technologies have been developed that permit the imaging of live animals using radiotracer emission, X-rays, magnetic resonance signals, fluorescence, and bioluminescence. The main objective of this review is to provide an overview of small animal molecular imaging, with a focus on nuclear imaging (single photon emission computed tomography and positron emission tomography). These technologies permit visualization of toxicodynamics as well as toxicity to specific organs by directly monitoring drug accumulation and assessing physiological and/or molecular alterations. Nuclear imaging technology has great potential for improving the efficiency of the drug development process.

• Journal of Chest Surgery
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• 제27권1호
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• pp.36-42
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• 1994

Between January 1990 and June 1993, the retrospective analysis was done in 48 consecutive patients with hemoptysis. According to clinical condition of patients, managements were divided into 3 subgroups; group 1[percutaneous bronchial artery embolization, group 2[operation after percutaneous bronchial artery embolization],group 3[delayed and emergency operation]. It was characterized that recurrence of hemoptysis was very frequent and most frequent underlying cause was pulmonary tuberculosis. In 40 patients[83%] urgent examination with flexible broncoscope was done and localization of the bleeding source was possible only in 24[60%] patients. The amount of hemoptysis was variable but there are no difference between groups and 22 patients[45%] had a prior episode of hemoptysis usually within 3 months of their admission. The recurrence was limited only in group 1[3/22] and the mortality rate was 6%[3/48]. We suggest that percutaneus bronchial artery embolization may be effective in recurrent massive hemoptysis but definitive management was operation.

• 대한두경부종양학회지
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• 제19권2호
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• pp.175-178
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• 2003

Benign lymphoepithelial cysts of parotid gland were first described by Miculicz in 1888, have been presented for a long time, uncommonly. But, recently it has been reported with increasing frequency since the onset of human immunodeficiency virus (HIV) infection. Benign lymphoepithelial cysts can be diagnosed by the fine needle aspiration in conjunction with the history and physical examination. The therapeutic options of benign lymphoepithelial cysts have been limited to aspiration, surgical resection, medical therapy, radiotherapy and sclerotherapy. Recently, we experienced a case of benign lymphoepithelial cyst of right parotid gland, so we report this case with review of the literatures.

• 한국항공운항학회지
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• 제14권2호
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• pp.39-44
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• 2006

The unsteady vortex lattice method is used to model lead-lag in flapping motions of a rectangular flat plate wing. The results for plunging and pitching motions were compared with the limited experimental results available and other numerical methods. They show that the method is capable of simulating many of the features of complex flapping flight. The lift, thrust and propulsive efficiency of a rectangular flat plate wing have been calculated for various lead-lag motion and reduced frequency with an amplitude of flapping angle(20o). To describe a motion profile of wing tip such as elliptic, line and circle, the phase difference of flapping and lead-lag motion was changed. And the effects of the motion profile on the aerodynamic characteristics of the flapping wing are discussed by examination of their trends.

• Wind and Structures
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• 제7권2호
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• pp.71-88
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• 2004

In this paper the capacity of Covariance Proper Transformation (CPT) analyses to provide information about the wind loading mechanisms of bluff bodies is investigated through the application to square cylinders. CPT is applied to the fluctuating pressure distributions on a single cylinder, as well as on a pair of cylinders in the tandem and side by side arrangements, with different separations. Both smooth and turbulent flow conditions are considered. First, through the analysis of the contributions of each CPT mode to the total fluctuating aerodynamic forces, a correspondence between modes and aerodynamic components is sought, which is then verified through examination of the mode shapes. When a correspondence between modes and aerodynamic components is found, an attempt is made to separate the different frequency contributions to the aerodynamic forces, provided by each mode. From the analyses it emerges that (a) in most cases each mode is associated to one single force component, that (b) retaining a limited number of modes allows reproducing the aerodynamic forces with a rather good accuracy, and that (c) each mode is mainly associated with one frequency of excitation.

• Journal of Chest Surgery
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• 제28권1호
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• pp.85-89
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• 1995

The early esophgeal carcinoma is limited to the mucosa or submucosa without lymph node metastsis which shows good 5-years survival rate. It is nearly 85-90% nowadays,if we just find and manage it.It is really helpful to use the endoscope in management and diagnosis, in addition the biopsy under the endoscopic finding.We experienced one case of early esophageal carcinoma. The patient was 57years old female,who ingested lye 27years ago for suicidal attempt, after 10years, the dysphagia was aggravated slowly. Before admission dysphagia was severely aggravated during 2months. Confirmation of diagnosis was made by endoscopic biopsy.Operation method was substernal colon bypass and total esophagectomy through right thoracotomy. Postoperative course was smooth.We report early esophgeal carcinoma related to lye stricture that was detected by the method of endoscopic examination and biopsy. It is important to screen the patients with longstanding history of benign esophageal stricture by the endoscopic biopsy.

• 식물분류학회지
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• 제50권1호
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• pp.80-83
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• 2020

We report Fimbristylis ovata (Burm.f.) J. Kern (Cyperaceae) from the sunny grasslands along the coastline on Jejudo Island, Korea, as a new distribution in Korea. This is thought to be the third confirmed record of this rare sedge in Korea; the first was from Gapari ('Is. Quelpaert') collected by Taquet in 1908, and the second was from Marado Island, collected by Kim and Kim in 2018. We found two new populations on Jejudo Island, the first with many individuals and the second with only a few plants. Following an examination of herbarium specimens, this species is considered to be rare and endangered in Korea, limited in distribution in Korea to Jejudo and Marado Islands.

• Structural Engineering and Mechanics
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• 제40권6호
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• pp.745-762
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• 2011

Damage detection methodologies based on the direct examination of the nonlinear-nonstationary characteristics of the structure dynamic response may play an important role in online structural health monitoring applications. Different signal processing based damage detection methodologies have been proposed based on the uncovering of spikes in the high frequency component of the structural response obtained via Discrete Wavelet transforms, Hilbert-Huang transforms or high pass filtering. The performance of these approaches in systems subjected to different types of excitation is evaluated in this paper. It is found that in the case of random excitations, like earthquake accelerations, the effectiveness of such methodologies is limited. An alternative damage detection approach using the Continuous Wavelet Transform (CWT) is also evaluated to overcome this limitation. Using the CWT has the advantage that the central frequencies at which it operates can be defined by the user while the frequency bands of the detail functions obtained via DWT are predetermined by the sampling period of the signal.

• 한국수학교육학회지시리즈A:수학교육
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• 제43권2호
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• pp.199-210
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• 2004

This study investigates 55 preservice secondary mathematics teachers' situational understanding of functional relationship. Functional thinking is fundamental and useful because it develops students' quantitative thinking about the world and analytical thinking about complex situations through examination of the relations between interdependent factors. Functional thinking is indispensable for understanding natural phenomena, for investigation by science, and for the technological inventions in engineering and navigation. Therefore, it goes without saying that teachers should be able to represent and communicate about various functional situations in the course of teaching and learning functional relationships to develop students' functional thinking. The result of this study illustrates that many preservice teachers were not able to appropriately represent and communicate about various functional situations. Additionally, it shows that most preservice teachers have limited understanding of the value of teaching function.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제53권6호
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• pp.305-311
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• 2004

Charge transport phenomena of polyaniline-DBSA/High Impact Polystyrene (PAM-DBSA/HIPS) blends have been studied through an examination of electrical conduction. HIPS used host polymer in the blends and PANI-DBSA obey a space charge limited conduction mechanism and a ohmic conduction mechanism respectively. However, PANI-DBSA/HIPS blends do not obey any classical conduction mechanism. Analysis of conduction mechanism revealed that the charging current of PANI-DBSA/HIPS blends increased with the increase of PANI-DBSA content. This result migrlt be explained by the reduction in the distance between PANI-DBSA particles enabling the charge carriers to migrate from a chain to a neighboring chain via hopping or micro tunneling. It was also found that the charging current of PANI-DBSA/HIPS blends decreased as the temperature was elevated, which is of typical phenomena in metals. It is speculated that the charge transport in PANI-DBSA particle was somewhat constrained due to strong phonon scattering.