초고속 HMC 주축계의 열특성 해석

김석일,김기상,김기태,나승표 한국공작기계학회 2001 한국공작기계학회 춘계학술대회논문집 Vol.2001 No.-

This paper presents the thermal characteristics analysis of a high-speed HMC spindle system with angular contact ball bearings, built-in motor, oil-jet lubrication method, oil jacket cooling method, and so on. The spindle system is composed of the main spindle and sub-spindle which are mechanically connected by a flexible coupling. The spindles are supported by two front and rear bearings, and the built-in motor is located between the front and rear bearings of the sub-spindle. The thermal analysis model of spindle system is constructed by the finite element method, and the thermal characteristics in the design stage are estimated based on temperature distribution and heat flow under the various testing conditions related to material of bearing ball, spindle speed and coolant temperature.

제2형 당뇨병 남성 환자에서 유리 테스토스테론과 성호르몬 결합 글로블린 농도

남기덕,김영설,박철영,오승준,김덕윤,우정택,김성운,양인명,김진우,최영길 대한당뇨병학회 2002 Diabetes and Metabolism Journal Vol.24 No.6

연구배경:인슐린저항성은 제2형 당뇨병과 심혈관질환의 주요한 위험 인자로 성호르몬과 상호 관계가 있다고 알려져 있다. 그러나 여성과는 달리 남성에서는 연령과 인슐린저항성에 따른 유리 테스토스테론과 성호르몬 결합 글로블린 농도의 변화에 대한 연구가 부족한 실정이다. 그러므로, 본 저자등은 제2형 당뇨병 남성 환자에서 정산인과 비교해서 유리 테스토스테론과 성호르몬 결합 글로블린 농도를 측정하고 연령에 따른 변화 정도를 알아보고자 하였다. 방법:대상 환자 모두에서 연령과 체질량지수, 총 콜레스테롤, 중성지방, 공복혈당과 인슐린 농도를 측정하였다. 혈중 유리 테스토스테론 농도는 방사면역측정법(radioimmunoassay)을 이용해서 측정하였고, 혈중 성호르몬 결합글로불린은 면역방사계측측정법(immunoradiometric assay)을 이용해서 측정하였다(Diagnostic System Laoratories, Wbster, TX, USA). 결과:1)제2형 당뇨병 남성 환자에서 정상 대조군 남성에 비해 성호르몬 결합글로불린은 104.1±35.0 vs 25.7±3.5 mole×10??로 의미 있게 높았으나(p<0.001), 유리 테스토스테론은 13.7±9.5 vs 13.6±6.5 ng/dL로 차이가 없었다. 2)연령과 성호르몬 결합 글로블린 사이의 상관 계수는 제2형 당뇨병 남성 환자에서 0.40로 중등고의 양의 상관 관계를 보였고(p<0.001), 정상 대조군 남성에서 0.11로 유의한 상관 관계를 보이지 않았다. 연령과 유리 테스토스테론 사이의 상관 계수는 제2형 당뇨병 남성 환자에서 0.08, 정상 대조군 남성에서-0.17로 모두에서 유의한 상관 관계를 보이지 않았다. 3)연령과 체질량지수를 보정한 후에 제2형 당뇨병 남성 환자와 정상 대조군 남성에서 혈중 인슐린 농도, 유리 테스토스테론과 성호르몬 결합 글로블린 사이에는 상관 관계가 없었다. 결론:제2형 당뇨병 남성 환자에서 정상 남성에 비해 성호르몬 결합 글로블린 농도가 증가되어 있었으며, 유리 테스토스테론은 차이가 없었다. 연령이 증가함에 따라 성호르몬 결합 글로블린이 제2형 당뇨병 남성 환자에서 정상 남성에 비해 증가 폭이 의미있게 컸으며, 유리 테스토스테론은 변화가 없었다. Background: Insulin resistance is a risk factor for cardiovascular disease and type 2 diabetes mellitus. There are many previous studies indicating that insulin lowers serum sex hormone-binding globulin levels, and there is inverse correlation between insulin resistance and serum sex hormone-binding globulin levels in women. However, in men, a limited number of studies are available to explain the effect of sex hormone on age and insulin. Therefore, the present study was undertaken to investigate the relationship among free testosterone, hormone-binding globulin and age in type 2 diabetic men and control subjects. Method: Age, body mass index, total cholesterol, triglyceride, fasting blood sugar, and insulin concentrations were examined on 89 type 2 diabetic men and 47 control subjects. The free testosterone level was measured by commercially available double-antibody system (Radioimmunoassay). The sex hormone-binding globulin level was also measured by commercially available double-antibody system(Immunoradiometric assay). Results: 1) Sex hormone-binding globulin level was significantly increased in patients with type 2 diabetes. However, there was no significantly difference in free testosterone level between the two groups. 2) Sex hormone-binding globulin was positively correlated with age (r=0.4, p <0.001) in patients with type 2 diabetes. Sex hormone-binding globulin and free testosterone were not correlated with age in control sujects. 3) Free testosterone and sex hormone-binding globulin concentrations were not significantly related to serum insulin concentration after adjusting for age and body mass index. Conclusions: We observed increased sex hormone-binding globulin concentration in diabetes man, and was a positively related to age. Further studies are needed to understand the relationships between age, insulin resistance, testosterone, and sex hormone-binding globulin concentrations(J Kor Diabetes Asso 24:699~707,2000).

Charge Coupled Device를 이용한 화상 분석 시스템에 대한 연구

김기준,성기천,이후설 대진대학교 2002 大眞論叢 Vol.10 No.-

It is very important to use the Charge Coupled Devices(CCDs) in spectrometric Analysis because we can study the molecular structures, molecular energy level, Intermolecular reaction, absorption or emission, photochemistry, weakly bound Molecular Energy, Fluorescence and Photo dynamic Therapy(PDT). CCD is very essential to study the molecular structures and medical engineering combining laser spectroscopy in the modem physical and chemistry. Thus, this study has manufactured and designed the electromagnetic spectrometric with CCD and then analyzed the phenomenon of foot. A video imaging system was studied for direct observation of the separated parts of bores during photons aborted and scattered. Data aquisition in addition with the possibility of further image processing, made it possible to clear and real image of the separated part of medical engineering. In the yesterday, CCD was thought to be used in only broadcasting system. But nowadays. it is thought to be used the industrial demand in observations, instrumentations and robotics as the industry develops.

마취제 혼합에 따른 Purple Membrane의 광순환반응에 부피 변화에 관한 연구

김기준,이후설 대진대학교 첨단소재연구소 1999 첨단소재연구소논문집 Vol.2 No.-

The excess volumes of mixing of benzyl alcohol, ethyl, alcohol, halothane, and procainein vesicle and in suspensions of several lipids have been etermined at 25℃ using a excess volume dilatometer. the potency of general aneathetics has long been known to correlate with lipid solubility Halobacteriun Halobium, were studied by absorption changes at280nm and fiuorescence ehanges at 330nm. The excess volumes of mixing in egg lecithin were all found to enegative, whereas they were positive in procaine and halothane. This result was confirmed as Miller's supposition.

한국대학생의 도덕사태 개념화 및 그 변화과정에 관한 연구(II)

송명자,조용하,설기문,김상윤 東亞大學校 學生生活硏究所 1992 學生硏究 Vol.20 No.-

This study aims to analyze the moral judgmental levels and the conceptions of transgressions of Korean college students in a series of multifacted events and the aspects of change in terms of moral judgmental level and conceptualizastion after with two years' college experience. The study was based on the Kohlberg's cognitive moral development theory and on the domain-distinction model in which children's intuitive abilities are stressed. This study was consisted of two sub-studies done in 1989 and 1991 respectively. The subjects of the 1st year study were 416 college students in four major cities(Seoul, Taegu, Kwangjoo, and Pusan). The subjects of the longitudinal analysis of second year study were 199 college students who could be followed up among the subjects of the 1st year study after two years. The instruments used in this study were Test of Moral Judgmental Development and Test of Conceptualization on Mulifaceted Events developed by the authors on the basis of Kohlberg's and Turiel's theories respectively. The following conclusions were obtained through the basis of the results and discussions of this study. First, Korean college students' false responses to moral issues decrease but the radical and anti-social responses increase after two years, and ther these responses are replaced by the level Ⅲmoral judgmental responses. Second, college students who are on the higher moral judgmental level conceptualize the transgression in social conventional and personal domains less permissible than those on the lower levels do. The students who are on the lower judgmental level reveal the decrese of nonpermissibility in social conventional domain with two years' college experience than those on the higher level do.

The Inhibitory Effect of Opioid on the Hyperpolarization-Activated Cation Currents in Rat Substantia Gelatinosa Neurons

Seol, Geun-Hee,Kim, Jun,Cho, Sun-Hee,Kim, Won-Ki,Kim, Jong-Whan,Kim, Sang-Jeong The Korean Society of Pharmacology 2001 The Korean Journal of Physiology & Pharmacology Vol.5 No.5

The action of opioid on the hyperpolarization-activated cation current $(I_h)$ in substantia gelatinosa neurons were investigated by using whole-cell voltage-clamp recording in rat spinal brain slices. Hyperpolarizing voltage steps revealed slowly activating currents in a subgroup of neurons. The half-maximal activation and the reversal potential of the current were compatible to neuronal $I_h.$ DAMGO $(1\;{\mu}M),$ a selective- opioid agonist, reduced the amplitude of $I_h$ reversibly. This reduction was dose-dependent and was blocked by CTOP $(2\;{\mu}M),$ a selective ${\mu}-opioid$ antagonist. DAMGO shifted the voltage dependence of activation to more hyperpolarized potential. Cesium (1 mM) or ZD 7288 $(100\;{\mu}M)$ blocked $I_h$ and the currents inhibited by cesium, ZD 7288 and DAMGO shared a similar time and voltage dependence. These results suggest that activation of ${\mu}-opioid$ receptor by DAMGO can inhibit $I_h$ in a subgroup of rat substantia gelatinosa neurons.

Prenatal exposure of ethanol induces increased glutamatergic neuronal differentiation of neural progenitor cells

Kim, Ki Chan,Go, Hyo Sang,Bak, Hae Rang,Choi, Chang Soon,Choi, Inha,Kim, Pitna,Han, Seol-Heui,Han, So Min,Shin, Chan Young,Ko, Kwang Ho BioMed Central 2010 JOURNAL OF BIOMEDICAL SCIENCE -BASEL- Vol.17 No.1

<P><B>Background</B></P><P>Prenatal ethanol exposure during pregnancy induces a spectrum of mental and physical disorders called fetal alcohol spectrum disorder (FASD). The central nervous system is the main organ influenced by FASD, and neurological symptoms include mental retardation, learning abnormalities, hyperactivity and seizure susceptibility in childhood along with the microcephaly. In this study, we examined whether ethanol exposure adversely affects the proliferation of NPC and de-regulates the normal ratio between glutamatergic and GABAergic neuronal differentiation using primary neural progenitor culture (NPC) and <I>in vivo </I>FASD models.</P><P><B>Methods</B></P><P>Neural progenitor cells were cultured from E14 embryo brain of Sprague-Dawley rat. Pregnant mice and rats were treated with ethanol (2 or 4 g/kg/day) diluted with normal saline from E7 to E16 for <I>in vivo </I>FASD animal models. Expression level of proteins was investigated by western blot analysis and immunocytochemical assays. MTT was used for cell viability. Proliferative activity of NPCs was identified by BrdU incorporation, immunocytochemistry and FACS analysis.</P><P><B>Results</B></P><P>Reduced proliferation of NPCs by ethanol was demonstrated using BrdU incorporation, immunocytochemistry and FACS analysis. In addition, ethanol induced the imbalance between glutamatergic and GABAergic neuronal differentiation <I>via </I>transient increase in the expression of Pax6, Ngn2 and NeuroD with concomitant decrease in the expression of Mash1. Similar pattern of expression of those transcription factors was observed using an <I>in vivo </I>model of FASD as well as the increased expression of PSD-95 and decreased expression of GAD67.</P><P><B>Conclusions</B></P><P>These results suggest that ethanol induces hyper-differentiation of glutamatergic neuron through Pax6 pathway, which may underlie the hyper-excitability phenotype such as hyperactivity or seizure susceptibility in FASD patients.</P>

Comparison of marginal bone loss between internal- and external-connection dental implants in posterior areas without periodontal or peri-implant disease

Kim, Dae-Hyun,Kim, Hyun Ju,Kim, Sungtae,Koo, Ki-Tae,Kim, Tae-Il,Seol, Yang-Jo,Lee, Yong-Moo,Ku, Young,Rhyu, In-Chul Korean Academy of Periodontology 2018 Journal of Periodontal & Implant Science Vol.48 No.2

Purpose: The purpose of this retrospective study with 4-12 years of follow-up was to compare the marginal bone loss (MBL) between external-connection (EC) and internal-connection (IC) dental implants in posterior areas without periodontal or peri-implant disease on the adjacent teeth or implants. Additional factors influencing MBL were also evaluated. Methods: This retrospective study was performed using dental records and radiographic data obtained from patients who had undergone dental implant treatment in the posterior area from March 2006 to March 2007. All the implants that were included had follow-up periods of more than 4 years after loading and satisfied the implant success criteria, without any peri-implant or periodontal disease on the adjacent implants or teeth. They were divided into 2 groups: EC and IC. Subgroup comparisons were conducted according to splinting and the use of cement in the restorations. A statistical analysis was performed using the Mann-Whitney U test for comparisons between 2 groups and the Kruskal-Wallis test for comparisons among more than 2 groups. Results: A total of 355 implants in 170 patients (206 EC and 149 IC) fulfilled the inclusion criteria and were analyzed in this study. The mean MBL was 0.47 mm and 0.15 mm in the EC and IC implants, respectively, which was a statistically significant difference (P<0.001). Comparisons according to splinting (MBL of single implants: 0.34 mm, MBL of splinted implants: 0.31 mm, P=0.676) and cement use (MBL of cemented implants: 0.27 mm, MBL of non-cemented implants: 0.35 mm, P=0.178) showed no statistically significant differences in MBL, regardless of the implant connection type. Conclusions: IC implants showed a more favorable bone response regarding MBL in posterior areas without peri-implantitis or periodontal disease.

Effect of luteal phase support with vaginal progesterone on pregnancy outcomes in natural frozen embryo transfer cycles: A meta-analysis

Seol, Aeran,Shim, Yoo Jin,Kim, Sung Woo,Kim, Seul Ki,Lee, Jung Ryeol,Jee, Byung Chul,Suh, Chang Suk,Kim, Seok Hyun The Korean Society for Reproductive Medicine 2020 Clinical and Experimental Reproductive Medicine Vol.47 No.2

Objective: The purpose of this study was to determine the effect of vaginal progesterone for luteal phase support (LPS) on the clinical pregnancy rate (CPR) in natural frozen embryo transfer (FET) cycles via a meta-analysis. Methods: We performed a meta-analysis of randomized controlled trials (RCTs) and retrospective studies that met our selection criteria. Four online databases (PubMed, Embase, Medline, and the Cochrane Library) were searched between January 2017 and May 2017. Studies were selected according to predefined inclusion criteria and meta-analyzed using R software version 2.14.2. The main outcome measure was CPR. Results: A total of 18 studies were reviewed and assessed for eligibility. One RCT (n = 435) and three retrospective studies (n = 3,033) met the selection criteria. In a meta-analysis of the selected studies, we found no significant difference in the CPR (odds ratio [OR], 0.96; 95% confidence interval [CI], 0.60-1.55) between the vaginal progesterone and control groups. An analysis of the two retrospective cohort studies that reported the live birth rate (LBR) following FET showed a significantly higher LBR in the vaginal progesterone group (OR, 1.72; 95% CI, 1.21-2.46). A subgroup meta-analysis of FET conducted 5 days after injection of human chorionic gonadotropin showed no significant differences between the two groups with regard to the CPR (OR, 1.18; 95% CI, 0.90-1.55) or miscarriage rate (OR, 0.73; 95% CI, 0.36-1.47). Conclusion: The results of this meta-analysis of the currently available literature suggest that LPS with vaginal progesterone in natural FET cycles does not improve the CPR.

A randomized controlled clinical study of periodontal tissue regeneration using an extracellular matrix-based resorbable membrane in combination with a collagenated bovine bone graft in intrabony defects

Kim, Sulhee,Chang, Hyeyoon,Hwang, Jin wook,Kim, Sungtae,Koo, Ki-Tae,Kim, Tae-Il,Seol, Yang-Jo,Lee, Yong-Moo,Ku, Young,Lee, Jong-Ho,Rhyu, In-Chul Korean Academy of Periodontology 2017 Journal of Periodontal & Implant Science Vol.47 No.6

Purpose: The purpose of this study was to investigate the feasibility of regenerative therapy with a collagenated bone graft and resorbable membrane in intrabony defects, and to evaluate the effects of the novel extracellular matrix (ECM)-based membrane clinically and radiologically. Methods: Periodontal tissue regeneration procedure was performed using an ECM-based resorbable membrane in combination with a collagenated bovine bone graft in intrabony defects around the teeth and implants. A novel extracellular matrix membrane (NEM) and a widely-used membrane (WEM) were randomly applied to the test group and the control group, respectively. Cone-beam computed tomography images were obtained on the day of surgery and 6 months after the procedure. Alginate impressions were taken and plaster models were made 1 week and 6 months postoperatively. Results: The quantity of bone tissue, the dimensional changes of the surgically treated intrabony defects, and the changes in width and height below the grafted bone substitutes showed no significant difference between the test and control groups at the 6-month examination. Conclusions: The use of NEM for periodontal regeneration with a collagenated bovine bone graft showed similar clinical and radiologic results to those obtained using WEM.