• Journal of the Korean Society for Precision Engineering
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• v.25 no.2
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• pp.148-155
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• 2008

The aim of the study is to interpret the distribution of occlusal force by 3-dimensional finite element analysis of ISP(Implant Supported Prosthesis) supported by minimum number of implant to restore the edentulous patients. For this study, the Astra Tech implant system is used. Geometric modeling for 6 and 4 fixture ISP group is performed with respect to the bone, implant and one piece superstructure, respectively. Implants are arbitrarily placed according to the anatomical limit of lower jaw and for the favorable distribution of occlusal force, which is applied at the end of cantilever extension of ISP with 30mm. Element type is tetrahedral for finite element model and the typical mechanical properties, Young's modulus and Poisson's ratio of each material, cortical, cancellous bone and implant material are utilized for the finite element analysis. From this study, we can see the distribution of equivalent stress equal to real situation and speculate the difference in the stress distribution in the whole model and at each implant fixture, From the analysis, the area of maximum stress is distributed on distal contact area between bone and fixture in the crestal bone. The maximum stress is 53MPa at the 0.2mm area from the bone-implant interface in the maximum side for 300N load condition for 4 fixture case, which is slightly less than the stress calculated from allowable strain. This stress has not been deduced to directly cause the loss of crestal bone around implant fixture, but the stress can be much reduced as the old peoples may have lower chewing force. Thus, clinical trial may be performed with this treatment protocol to use 4 fixtured ISP for old patients.

• The Journal of Korean Society for Radiation Therapy
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• v.8 no.1
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• pp.29-35
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• 1996

We are often faced with the clinical situations that is inevitably extended SSD for electron beam therapy due to anatomical restriction or applicator structure. But there are some difficulties in accurately predicting output and properties. In electron beam treatment , unlike photon beam the decrease in output for extended SSD does not follow inverse-square law accurately because of a loss of side scatter equilibrium, which is particularly significant for small cone size and low energies. The purpose of our study is to analyze the output in changing with the energy, cone size, air gap beyond the standard SSD and to compare inverse-square law factor derived from calculated effective SSD, mominal SSD with measured output factor. In addition, we have analyzed the change of PDD for several cones with different SSDs which range from 100cm to 120cm with 5cm step and with different energies(6MeV, 9MeV, 12MeV, 16MeV, 20MeV). In accordance with our study, an extended SSD produces a significant change in beam output, negligible change in depth dose which range from 100cm to 120cm SSDs. In order to deliver the more accurate dose to the neoplastic tissue, first of all we recommend inverse-square law using the table of effective SSDs with cone sizes and energies respectively or simply to create a table of extended SSD air gap correction factor. The second we need to have an insight into some change of dose distribution including PPD, penumbra caused by extended SSD for electron beam therapy.

• The Korean Journal of Pain
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• v.26 no.4
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• pp.336-346
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• 2013

Intrathecal drug delivery is an effective and safe option for the treatment of chronic pathology refractory to conventional pain therapies. Typical intrathecal administered drugs are opioids, baclofen, local anesthetics and adjuvant medications. Although knowledge about mechanisms of action of intrathecal drugs are every day more clear many doubt remain respect the correct location of intrathecal catheter in order to achieve the best therapeutic result. We analyze the factors that can affect drug distribution within the cerebrospinal fluid. Three categories of variables were identified: drug features, cerebrospinal fluid (CSF) dynamics and patients features. First category includes physicochemical properties and pharmacological features of intrathecal administered drugs with special attention to drug lipophilicity. In the second category, the variables in CSF flow, are considered that can modify the drug distribution within the CSF with special attention to the new theories of liquoral circulation. Last category try to explain inter-individual difference in baclofen response with difference that are specific for each patients such as the anatomical area to treat, patient posture or reaction to inflammatory stimulus. We conclude that a comprehensive evaluation of the patients, including imaging techniques to study the anatomy and physiology of intrathecal environment and CSF dynamics, could become essential in the future to the purpose of optimize the clinical outcome of intrathecal therapy.

• The Korean Journal of Quaternary Research
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• v.17 no.2
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• pp.117-122
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• 2003

This study is conducted to examine the woods that were excavated at Jangdo Island. The Jangdo site is located in a small island some 180 meters away from the main island of Wando, Jeollanam-do in southern Korea. This site is known as Cheong-Hea Jin fort for the marine King Jang Bogo during the early 9$^{th}$ century. Total of 101 specimens were collected in three groups； small-size piles, log fences (Mok-check) and logs from a well. The species of the group of piles consisted of Quercus spp. (43%), Pinus densiflora (29%), Pinus koraiensis (5%), Alnus japonica (3%), Fraxinus spp. (3%), Styrax obassia (3%), Juglans spp. (2%), Zelkova serrata (2%), Platycarya strobilacea (2%), Celtis spp. (2%), Torreya nucifera (2%), Quercus myrsinaefolia (2%), and Cinnamomum spp. (2%). The species of Mok-check and logs from the well were identified as all Pinus densiflora. The species composition indicated that the climate around A. D. 9th-10th century in southern Korea was similar to the present.. The wooden fences were also examined for tree-ring analysis. The ages of woods were 50∼60 years. We made two site chronologies. The chronologies indicated that southeastern and southwestern fences were repaired frequently. The results could not give the absolute dates due to lack of reference chronologies in this period.

• Journal of Korean Neurosurgical Society
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• v.29 no.10
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• pp.1303-1308
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• 2000

Objectives : It has been known that vascular endothelial growth factor(VEGF), as an endothelial cell-specific mitogen, induces angiogenesis, and possesses vascular permeability and procoagulant properties. Peritumoral brain edema(PTBE) is a common accompaniment of malignant gliomas. It results from microvascular extravasation of plasma and proteins through the interendothelial spaces. The correlation between pathological grading, PTBE, neovascularization, and the expression of VEGF were analyzed in 31 patients with astrocytic tumors. Methods : Astrocytic tumor samples(8 astrocytomas, 14 anaplastic astrocytomas, and 9 glioblastomas) from 31 patients( 21 males and 10 females : average age $37{\pm}24$ years) who underwent surgery were examined retrospectively for the expression of VEGF and CD31(microvasculature) immunohistochemically. The extent of PTBE was examined by using preoperative CT or MRI as an edema index(EI). In addition to VEGF and CD31, several causative factors including tumor size, histologic type were compared with EI. Results : Only one of 8 astrocytomas, and majority of high grade(21 of 23 anaplastic astrocytomas and glioblastomas) tumors demonstrated PTBE(p<0.05). The majority of high grade tumors showed higher expression of VEGF (p<0.01). High grade tumors showed even higher CD31 expression(p<0.05), however, there was no close correlation between expression of VEGF and CD31. The EI was increased significantly, just as VEGF(p<0.01), but CD31 expression was not correlated with high EI. Conclusion : These data suggest that VEGF expression is closely correlated with PTBE and histological grading in astrocytic tumors. Microvasculature(CD31) in tumors is highly correlated with histological grading, however, shows no correlation with the expression of VEGF and PTBE.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.5
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• pp.544-549
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• 2000

The treatment of TMJ ankylosis poses a significant challenge because of technical difficulties and high incidence of recurrence. TMJ ankylosis has been treated by excision and total joint reconstruction with alloplastic, allogeneic, autogenous materials as interpositional materials. The temporalis myofascial flap had been considered to be a successful interpositional material, due to its anatomical, topographical, and functional properties. This study evaluated the efficacy of the temporalis myofascial flap for nine TMJs (five patients) through the preauricular approach and coronoidectomy. Radiographic and physiologic long term result was investigated in this study. The result reveals that the temporalis myofascial flap is a good autogenous tissue satisfying the criteria of an ideal interpositional material, which offers a material that fulfills the physiological function of the disc. In spite of favorable functional outcome, mild postoperative openbite tendency remains another challenge.

• Journal of the Korean Wood Science and Technology
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• v.33 no.6 s.134
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• pp.17-24
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• 2005

Korean pine (Pinus koraiensis Sieb.et Zucc.) boards of 30 mm thickness were treated by steaming and four different drying methods. Small specimens were taken from the sapwoods of the treated boards and their longitudinal liquid permeability was measured according to Darcy's law. The specimens were also extracted with alcohol and aceton solutions to examine the mechanism of liquid flow in wood. It was observed that specific permeability drastically decreases with measurement time, resulting in violation of Darcy's law. It may be due to that air bubbles formed under vacuum block flow paths in resin canals. The average specific permeabilities of non-extracted and extracted specimens are different from one treatment to another. It is supposed that the properties of residual resin in resin canals change depending on the conditions of treatments. Anatomical examination was conducted with a scanning electron microscope.

• Journal of the Korea Computer Graphics Society
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• v.16 no.3
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• pp.21-30
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• 2010

We present a real-time simulation method for muscles which are actuated by skeletal structure based on anatomical properties of the muscles. Muscles are designed by their two endpoints attached to either bones or other muscles and their volume are preserved approximately during the deformation. Skin deformation animation is obtained by a simple skinning due to the muscle deformation. We present also the performance data for a human-like multi-linked character which has bones, muscles, and skin. According to our experimental result, we can get skin deformation animation with a few tens of muscles in real-time. The method proposed in this paper can be applied to obtain skin deformation animation for multi-linked characters appear frequently in real-time environments such as games.

• Korean Journal of Veterinary Research
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• v.61 no.4
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• pp.39.1-39.6
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• 2021

The classification of the bone pieces excavated from Gasan-ri archaeological site 1 in Jinju, presumed to be relics was investigated macroscopically. The remains of the animal bone were 3 classes (Mammalia, Aves, Amphibia), 5 orders (Carnivora, Artiodactyla, Galliformer, Rodentia, Salientia), and 6 species (Sus scrofa, Cervidae sp., Nyctereutes procyonides, Phasianidae, Rattus norvegicus caraco, Rana nigromaculata). The total weight of the animal bone remains was 1,002.80 g, with the identified bones comprising 975.30 g and an identification rate of 97.26%. A total of 447 animal bone fragments were identified, including 204 bone pieces of S. scrofa (468.00 g, 47.99%), 102 bone pieces of Cervidae sp. (453.79 g, 46.53%), 68 bone pieces of R. nigromaculata (4.69 g, 0.48%), 59 bone pieces of N. procyonides (47.14 g, 4.83%), 9 bone pieces of Phasianidae (0.98 g, 0.10%), and 5 bone pieces of Rattus norvegicus caraco (0.70 g, 0.07%). The bone pieces of the animal relics consisted of 81 skull (18.12%), 161 axial skeleton (36.02%), 64 forelimb (14.32%), and 141 hindlimb (31.54%) fragments. The archaeological significance of the animal bones excavated in this investigation was that wild boars and deer were presumed to have been mainly used animals in the Gasan-ri area of Jinju during the Three Kingdoms period.

• Clinical and Experimental Reproductive Medicine
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• v.50 no.3
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• pp.143-153
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• 2023

Objective: Men's sexual health plays an important role in male fertility and childbearing, as it is associated with factors such as sexual desire, healthy spermatogenesis, and erectile function. In various cultures, medicinal plants have been utilized to address male sexual issues, including infertility and erectile dysfunction. Despite recent advancements in medical science for treating male impotence, some men opt for herbal supplements as an alternative, given that numerous herbs have the potential to enhance male sexual performance. The Apiaceae family is one of the oldest plant families used for medicinal purposes. Ferula, a genus within this family, comprises approximately 170 different species worldwide. Members of this genus possess numerous therapeutic properties due to the presence of various compounds. This article aims to explore the potential impacts of Ferula plants on the male reproductive system. Methods: This review article was prepared by searching for terms including Ferula and "aphrodisiac," Ferula and "spermatogenesis," and Ferula and "male reproductive system." Relevant information was gathered through electronic databases, including ISI Web of Knowledge, PubMed, and Google Scholar. Results: The findings indicated that relatively comprehensive studies have been conducted in this area, revealing that certain Ferula species have been employed in folk medicine to boost fertility and libido. Recent research has corroborated these effects. Conclusion: It is hoped that new aphrodisiac compounds with fewer side effects can be isolated from Ferula plants in the future.