노인의 팔 굽힘/폄 저항 운동 시 하중 증가에 따른 근육의 활성도 및 기여도 분석

김현동(Hyun Dong Kim),황성재(Sungjae Hwang),손종상(Jongsang Son),김한성(Han Sung Kim),김영호(Young Ho Kim) 대한인간공학회 2009 大韓人間工學會誌 Vol.28 No.4

The purpose of this study was to assess activation and contribution of muscles of the elderly according to increased loading during the arm flexion extension resistance exercise. Surface electromyographic signals were acquired from biceps brachii, triceps brachii, deltoid posterior, pectoralis major and latissimmus dorsi to determine the difference of the activation of specific muscles between the elderly and young. Five elderly and five young males with no musculoskeletal disease volunteered for the study. Electromyographic activities in the muscles were measured during resistance exercise and normalized to the maximum EMG activity recorded in the maximal voluntary static contraction (MVC). Against the increased loading during arm flexion/extension resistance exercises, the young uses muscles evenly but the elderly uses one specific muscle frequently. Contribution of triceps brachii during extension and deltoid posterior during flexion was principal in the elderly.

데스크탑 밀링머신의 고속 스핀들 설계 해석

장성현,황현영,정우영,홍정표,최영휴 한국공작기계학회 2009 한국공작기계학회 춘계학술대회논문집 Vol.2009 No.-

During a decade, there are many researches on microfactory which is the miniature, flexible, and efficient manufacturing system for the micro/meso scale machining device. Moreover many micro machine tool has developed in Japan, U.S., Europe, and Korea. Already we are developing a desktop milling machine with 380×450×450 ㎣ machine size for microfactory or BT (Bio technology) factory. In this study, we carried out the design analysis of a high speed spindle system for our desktop milling machine by using ADROS, which is our own developed S/W for dynamic design analysis of rotor systems. As the result, we obtained some analyzed dynamic characteristics of a spindle system, such as natural frequency, whirl frequency, critical speed, and harmonic response.

Increased 11β-hydroxysteroid dehydrogenase type 1 contributes to barrier dysfunction in aged skin

( Beom Jun Kim ),( Noo Ri Lee ),( Chung Hyeok Lee ),( Young Bin Lee ),( Solam Lee ),( Hyun Jee Hwang ),( Eunjung Kim ),( Eung Ho Choi ) 대한피부과학회 2019 대한피부과학회 학술발표대회집 Vol.71 No.2

Background: 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) converts inactive cortisone into cortisol, an active form, and is expressed by several tissues including the skin. Excessive active glucocorticoid (GC) deteriorates skin barrier function. Objectives: To find out if 11β-HSD1 affects on the barrier function in aged skin. Methods: We have performed human and in vivo studies. We measured cortisol in stratum corneum (SC) and oral epithelium of the elderly and young. Hairless mice were used for 11β-HSD1 immunohistochemistry staining of skin and measuring skin barrier function and serum cytokines. 11β-HSD1 knock-out (KO) mice and its wild-type were used for measuring lipid synthesis related enzyme. Results: Cortisol levels were elevated in SC and oral epithelium of the elderly rather than young. The 11β -HSD1 expression was increased in immunohistochemistry stain of aged mice skin. Aged mice showed decreased transepidermal water loss (TEWL) and SC hydration, and increased SC integrity than young. Serum inflammatory cytokines including interleukin-1α, -4, -10, -31 and tumor necrosis factor-α were increased in aged mice than young. The expressions of lipid synthesis related enzymes in epidermis were elevated in KO mice and topical 11β -HSD1 inhibitor applied mice. Conclusion: 11β-HSD1 expression is elevated in aged skin. It increases active GC and then deteriorates skin barrier function.

부산시 사회지역특성에 관한 연구

황영우,윤철현 동아대학교 건설기술연구소 1997 硏究報告 Vol.21 No.2

Social Area Analysis is valuable method to understand urban land use pattern by there residents. The result of this study using factor and cluster analyses is similar to the our common understanding on Pusan situations. Puasn can be divided 9 homogeneous regions through this study. The types of Pusan land use pattern cannot be fitted to Concentric Zone Theory, Sector Theory and Multiple Nuclei Theory like western cities. But the social determinants - invasion and succession, concentration and deconcentration, centralized decentralization system- were discovered partly in Pusan. The economic and public determinants have to be considered with complexity for the much deeper understanding on Pusan land use pattern.

녹차분말을 첨가한 국수의 조리 특성에 관한 연구

현영희,황윤경,이윤신 동아시아식생활학회 2001 동아시아식생활학회지 Vol.11 No.4

This study was conducted to investigate the cooking properties of noodles made from composite flour blended with green tea powder. As the ratio of green tea powder increased, development time was longer than that of the control. The stability of dough showed higher value than the control except 2% addition group. The highest viscosity was at the 4% addition group, but 2% addition group showed the lowest viscosity. As the additional ratio of green tea powder was increased, the volume expansion ratio was increased, but water soluble solid matters contents in all addition groups had a lower level than that of the control. Also, the yellowness level of noodle was increased, but the brightness, redness and color and flavor acceptability was decreased, as the additional ratio was increased. However, 2~4% addition group of green tea powder had a similar acceptability profile to that of the control group.

GIS을 이용한 釜山市 公共的 土地利用패턴 分析

황영우,윤철현 東亞大學校 建設技術硏究所 1999 硏究論文集 Vol.22 No.2

This study tries to analyze land use pattern by zoning through urban spatial structure. Land uses in Pusan are mixed using in spite of zoning operation. New residential area is made like a frog leaping to the outer of the City. The efficiency of existing residential area is very low to compare with newly developed area cause of delayed regeneration. Especially the existing built-up area of Pusan in insufficient in adaptability and preparation going with the change of urban spatial structure, particularly with the zoning system. Therefore, detailed and scientific feasible plan should be established to have reasonable residential environment.

Ethyoene Oxide 폭로 근로자의 말초 임파구 자매염색분체 교환에 관한 연구

황천현,박종태,장성훈,김대성,이원진,김청식,김영환 大韓産業醫學會 1998 대한직업환경의학회지 Vol.10 No.4

Operators of hospital sterilizers who use ethylene oxide(EtO) were studied to determine the exposure of EtO level and the frequency of sister chromatid exchanges(SCEs) from June 12 to July 20, 1997. To evaluate SCEs in the peripheral blood cells, we selected 22 workers at the central supply room of 4 university hospitals and 22 unexposed workers at the same hospitals according to match sex, age, and smoking habit and also did questionnaires. The mean air concentrations(8-hr TWA) of EtO at 4 university hospitals were less than 1 ppm. The SCE frequencies in exposed workers to EtO and controls were normally distributed. The SCE frequencies in exposed workers to EtO and controls were 6.42±0.63, 5.86±0.69, respectively and their differences were statistically significant(p=0.0093). But there were no statistically significant differences in smoking, alcohol intake, coffee drinking. Especially smokers who exposed to EtO were increased SCE statistically significant than the exposed group who did not smoke.

두가지 혈류 유발방법에 의한 새로운 심폐소생술(이중 혈류 유발 심폐소생술)장치의 개발

황성오,김현,조준휘,오범진,임종천,최경훈,윤정한,이승환,김영식,이강현,이윤선 大韓應急醫學會 1999 대한응급의학회지 Vol.10 No.2

Background: There have been many efforts to augment blood flow during cardiopulmonary resuscitation. These efforts have focused on maximizing the effect of cardiac pump or thoracic pump alone. However, considering that the heart is the biggest blood reservoir and increase of intrathoracic pressure can generate blood flow, simultaneous exploitation of both mechanisms may have synergistic effect. We hypothesized that simultaneous chest constriction in addition to sternal compression by standard CPR may have additive hemodynamic effects by preventing deformation of the chest and increase of intrathoracic pressure. Methods and results: we built a new mechanical device to perform compression and thoracic constriction simultaneously. The device consists of two main elements. Piston in the center is to depress the sternum. Strap is to constrict the thorax circumferentially. Strap is attached to both sides of the piston. When the piston is pushed down, it depresses the sternum and pulls on the thoracic strap. To determine strap width to produce optimal hemodynamic effect, we measured hemodynamic parameters with variable widths of strap in two dogs after induction of ventricular fibrillation. Result of the experiment showed that 10cm wide strap was determined to be most effective. We also determined optimal depth of compression to produce maximal hemodynamic effect with animal experiments using two dogs. Animal experiments showed that the highest aortic pressure could be generated when the stemum was depressed to 5 cm. Cardiopulmonary resusciation using a new device could generate higher systolic aortic pressure, coronary perfusion pressure and end-tidal carbon dioxide tension in comparison with standard cardiopulmonary resuscitation in a pilot animal study using two dogs. Conclusion: New cardiopulmonary resuscitation method using a mechanical device designed by us could perform sternal compression and simultaneous thoracic constriction, and generate better hemodynamic effects than standard cardiopulmonary resuscitation in pilot animal experiments.

색상 측정 기기를 이용한 복합레진 적층 수복과 단일 수복의 색상 비교 분석

송영상,김자현,이빈나,장지현,장훈상,황윤찬,오원만,황인남 大韓齒科保存學會 2012 Restorative Dentistry & Endodontics Vol.37 No.2

Objectives: This study analyzed the difference in color caused by different thickness in enamel layer of composite resins when applied with single and layering placement technique, and evaluated if the results agreed with the shade guide from the manufacturers to verify reliability of the color matching process of the manufacturers. Materials and Methods: For single composite resin samples, 6 mm diameter and 4 mm thickness cylindrical samples were fabricated using Ceram-X mono (DENTSPLY DeTrey) and CIE L*a*b* values were measured with spectrophotometer. Same process was done for layering compositie resin samples, making 3 dentinal shade samples, 4 mm thickness, for each shade using Ceram-X duo (DENTSPLY DeTrey) and enamel shade resins were layered in 2 mm thickness and CIE L*a*b* values were measured. These samples were ground to 0.2 mm thickness each time, and CIE L*a*b* values were measured to 1 mm thickness of enamel shade resin. Results: Color difference (△E*) between single and layering composite resin was 1.37 minimum and 10.53 maximum when layering thicknesses were between 1 mm and 2 mm and 6 out of 10 same shade groups suggested by manufacturer showed remarkable color difference at anythickness (△E* > 3.3). Conclusion: When using Ceram-X mono and duo for composite resin restoration, following the manufacturer's instructions for chossing the shade is not appropriate, and more accurate information for Ceram-X duo is needed on the variation and expression of the shades depending on the thickness of the enamel. (Restor Dent Endod 2012;37(2):84-89)

The expression patterns of RANKL and OPG in murine tooth eruption

Hwang, Kyung-Mun,Kim, Eun-Jung,Kim, Hyun-Jung,,Kim, Young-Jin,Nam, Soon-Hyeun 大韓小兒齒科學會 2006 大韓小兒齒科學會誌 Vol.33 No.2

치아의 맹출은 치아기 (dental organ)와 치조골의 세포와 연관된 매우 복잡한 과정이다. 우선 치아 맹출이 일어나기 전에 파골세포가 치낭으로 집결하게 된다. 이러한 치낭의 역할은 파골세포와 조골세포의 상호작용으로 이루어 지는 골개조와 밀접한 관련이 있는데, 이는 치아 맹출과 연관된 많은 유전자들이 치낭에서 발현되기 때문이다. RANKL는 TNF ligand family로써 조골세포에 존재하며 파골세포의 형성 및 전구세포로 부터의 활성화를 유도한다. 이러한 RANKL은 OPG에 의해 그 작용이 억제되며 RANKL와 OPG의 상대적인 비율이 파골세포의 형성에 영향을 미친다. 또한 Runx2유전자의 변이는 조골세포의 분화와 활성에 차질을 가져오고 결국 RANKL/OPG pathway를 통해 파골세포 형성에 영향을 줄 수 있다. 치아의 발육 및 맹출에 미치는 RANKL 및 OPG의 영향을 알아보고 Runx2와의 연관성을 알아보기 위해 in situ hybridization 방법으로 태생 1, 3, 5, 7, 9, 11일된 쥐의 하악 및 제1대구치를 사용하여 실험을 실시한 결과 RANKL, OPG, Runx2의 mRNA가 태생 1일부터 11일까지 치낭 및 치아주위조직에 특성있게 나타났다. 이중 태생 5일에서 9일 사이에 RANKL 및 Runx2는 치아의 교합면측과 하방 치조골 부위의 발현이 강하게 나타난 반면 OPG는 약한 발현을 보였다. 이는 또한 파골세포의 활성부위를 알아보기 위해 TRAP염색을 실시하여 태생 5일에서 9일 사이에 최대의 활성화를 나타낸 결과와 연광성 있게 나타났다. RANKL, OPG, Runx2의 특성있는 발현양상들을 종합해 볼 때, 치아 맹출은 치낭, 치아기, 치조골 사이의 상호 작용을 통해 이루어 지며, 이는 치낭이 치아 맹출에 있어서 매우 중요하다는 것을 의미한다. 또한, 이러한 유전자들 (RANKL, OPG, Runx2) 이 치아의 맹출에 중요한 역할을 하는 것으로 사료된다. Tooth eruption is a complex and tightly regulated process that involves cells of the tooth organ and the surrounding alveolus. Osteoclast precursors must be recruited into the dental follicle prior to the onset of eruption. This function of dental follicle may be regarded as the ability of bone remodeling characterized by the interaction of osteoclasts and osteoblasts. This is because tooth eruption is a localized event in which many of the genes required for eruption are expressed in the dental follicle. RANKL is a membrane-bound protein that is a member of the TNF ligand family, which is present on bone marrow stromal cells and osteoblasts, and induces osteoclast formation and activation from precursor cell. The biologic effect of RANKL is inhibited by OPG and, in bone, the relative ratio of RANKL and OPG modulates osteoclastogenesis. To evaluate the roles of RANKL and OPG in tooth eruption and the relations with the expression pattern of Runx2, in situ hybridization was performed with mandibles of mice at postnatal stage 1, 3, 5, 7, 9 and 11. mRNA of RANKL, OPG, and Runx2 are expressed in dental follicle and surrounding tissue from P1 to 11. To determine the sites of osteoclastic activity duing tooth eruption, mandibles were dissected. Peak osteoclastic activity in alveolar bone along the occlusal and basal regions was observed from P5 to 9, with osteoclasts in these regions being large and strongly TRAP-positive. The specific spatic-temporal expression patterns of RANKL, OPG and Runx2 in our study suggest that tooth eruption could be progressed through the interactions of molecular signaling among dental follicle, dental organ and alveolar bone, furthermore it means that dental follicle is quite important in tooth eruption. In addition, it indicates that these genes (RANKL, OPG, and Runx2) play critical roles in tooth eruption.