Brain Topological Correlates of Motor Performance Changes After Repetitive Transcranial Magnetic Stimulation

Park, Chang-hyun,Chang, Won Hyuk,Yoo, Woo-Kyoung,Shin, Yong-Il,Kim, Sung Tae,Kim, Yun-Hee Mary Ann Liebert 2014 Brain connectivity Vol.4 No.4

<P>Repetitive transcranial magnetic stimulation (rTMS) influences the brain temporally beyond the stimulation period and spatially beyond the stimulation site. Application of rTMS over the primary motor cortex (M1) has been shown to lead to plastic changes in interregional connectivity over the motor system as well as alterations in motor performance. With a sequential combination of rTMS over the M1 and functional magnetic resonance imaging (fMRI), we sought changes in the topology of brain networks and specifically the association of brain topological changes with motor performance changes. In a sham-controlled parallel group experimental design, real or sham rTMS was administered to each of the 15 healthy subjects without prior motor-related dysfunctions, over the right M1 at a high frequency of 10 Hz. Before and after the intervention, fMRI data were acquired during a sequential finger motor task using the left, nondominant hand. Changes in the topology of brain networks were assessed in terms of global and local efficiency, which measures the efficiency in transporting information at global and local scales, respectively, provided by graph-theoretical analysis. Greater motor performance changes toward improvements after real rTMS were shown in individuals who exhibited more increases in global efficiency and more decreases in local efficiency. The enhancement of motor performance after rTMS is supposed to be associated with brain topological changes, such that global information exchange is facilitated, while local information exchange is restricted.</P>

A neurometabolite study of chronic daily headache in patients with systemic lupus erythematosus using magnetic resonance spectroscopy: comparison with fibromyalgia patients and healthy controls

( Chang-nam Son ),( Sang-hyon Kim ),( Hyuk Won Chang ),( Ji-min Kim ) 대한내과학회 2016 The Korean Journal of Internal Medicine Vol.31 No.6

Background/Aims: Neuropsychiatric systemic lupus erythematosus (SLE) includes a broad spectrum of neurologic and psychiatric manifestations. One of the most commonly observed neuropsychiatric symptoms is headache. However, the lack of specific clinical distinctions for headache in SLE has made it diffi cult to elucidate its pathophysiology. The aim of this study is to evaluate the neurometabolic changes using Proton Magnetic Resonance Spectroscopy (1H-MRS) in patients with SLE who suffer from chronic daily headache (CDH). Methods: SLE and fibromyalgia patients with CDH and healthy controls were recruited (n = 9, n = 5, and n = 6, respectively). 1H-MRS metabolite ratios were evaluated in bilateral basal ganglia (BG) and bilateral peritrigonal white matter (PWM). Results: 1H-MRS showed a significantly decreased N-acetylaspartate (NAA)/creatine (Cr) ratio in right BG in SLE patients with CDH compared to fibromyalgia patients with CDH and normal controls (p = 0.029 and p = 0.020, respectively). Left PWM NAA/Cr and choline/Cr ratios in SLE patients with CDH were lower than those in fibromyalgia patients with CDH (p = 0.019 and p = 0.029, respectively). Conclusions: This study suggests the possibility that CDH in patients with SLE might be associated with neuronal dysfunction and neurometabolic changes.

A study on the dynamic behavior of the Korean next-generation high-speed train

Jeon, Chang-Sung,Kim, Young-Guk,Park, Joon-Hyuk,Kim, Seog-Won,Park, Tae-Won Professional Engineering Publishing Ltd 2016 Proceedings of the Institution of Mechanical Engin Vol. No.

<P>This study describes the dynamic behavior of the HEMU-430X, the Korean next-generation high-speed train. The HEMU-430X was initially analyzed using VAMPIRE, a computer program that is used to examine the dynamics of railway vehicles, based on which it was expected to sway strongly at its tail end. This hunting motion was expected to disappear when the position of the yaw damper was changed. The dynamic behavior of the HEMU-430X was assessed in an on-track test performed using the protocols in the EN14363 standard and measuring the carbody, bogie and axle accelerations; the HEMU-430X was found to satisfy the safety criterion. The hunting motion appeared at speeds of 150, 350 and 387km/h, and countermeasures such as changing the position of the yaw damper, installing carbody dampers, and increasing the damping coefficient of the yaw damper installed on the motor car containing the driver's cab were taken in order to reduce the vibrations. Ultimately, the highest test speed achieved was 421.4km/h. Subsequently, it was found that the critical speed tended to decrease with mileage. This was attributed to excessive lateral damping and a revised design was proposed to solve this problem.</P>

Vitamin E가 酸素中毒耐性에 미치는 影響에 關한 實驗的 硏究

李宇爀,車喆煥,李元暢 고려대학교 의과대학 1975 고려대 의대 잡지 Vol.12 No.3

In order to study the preventive measure of an oxygen toxicity under higher oxygen pressure, rats were given vitamin E and then exposed to at 2 atmospheres of 100% oxygen. Comparison group which was not administered with vitamin E was also exposed to at 2 atmospheres of 100% oxygen. Time required to evoke convulsion, correlation between treated dosage of vitamin E and time required to evoke convulsion, half-lethal time and its mean, correlation between treated dosage of vitamin E and fatal time, ratio of lung weight to body weight, and histo-pathological findings of the lungs were carefully examined. Some interesting results acquired through this study were thus: 1) Average time required to evoke convulsion of rats exposed to at 2 atmospheres of 100% oxygen was 103.7±2.5 min in comparison group and 179.0±9.5 min. or 202.1±2.7 min. in experimental groups administered with 25㎎ or 35㎎ of vitamin E per day respectively. Time required to evoke convulsion in experimental groups administered with vitamin E was longer than in comparison group. Higher correlation between time required to evoke convulsion and treated dosage of vitamin E was shown as r=+0.998 (p<0.01). 2) Average half-lethal times were 210 min. in comparison group and 325 min., 335 min. in groups administered with 25㎎, 35㎎ of vitamin E per day respectively. Statistically high correlation between treated dosage of vitamin E and half-lethal time was reported as r=+0.852(p<0.01). 3) Weight ratio of lung to body was significantly higher in experimental group exposed to high oxygen tension than control group not exposed to high oxygen tension, but there was no significant difference among experimental groups. 4) Lung damage was more severe in half-lethal group than in servival group during experiment. Histological changes of the lungs were that of vascular congestion, hemorrhage, pulmonary edema and emphysematous change. And the degree of changes was rather marked in experimental group than in comparison group. There was no difference in the degree of changes by the doses of vitamin E administered in experimental groups. 5) Vitamin E would be an effective agent for the prevention of oxygen poisoning under the high oxygen pressure. Effect of vitamin E administration before exposing to hyperbaric oxygen tension must be pondered to utilize in the "hyperbaric medicine".

삼출성 중이염 환자에서의 혈중 및 아데노이드 면역글로불린 E의 면역혈청학적 연구

장혁순,강성호,유창수,김성현,이병돈,박영진,윤세동,안희영,강주원 순천향의학연구소 1997 Journal of Soonchunhyang Medical Science Vol.3 No.1

Otitis media with effusion (OME) is one of the most common disease in children but its pathogenesis is not clear. In particular the role of allergy has revealed conflicting support with widely varing opinions as to its importance. Within recent years, striking biochemical and immunochemical analytic techniques have opened a new approach the study of otitis media with effusion. So we focused on distributions of IgE in adenoid tissue and serum IgE levels. Authors compared the serum IgE and the distribution of IgE in adenoid tissue between the 20 patients underwent tonsillectomy, adenoidectomy and ventilating tube insertion and control group of 11 patients underwent tonsillectomy and adenoidectomy. The results were as follows; 1. In the distribution of IgE in adenoid tissue, there was a significant increase in the group of patients with OME compared to the control group (P<0.01). 2. In the analysis of serum IgE levels, the levels of IgE in the OME patients an control group were higher than normal level, although the level of IgE in the OME patients were less than that of control group, there was no significance P>0.05).

Arthroscope 시스템 설계에 관한 연구

장민혁,김형범,김태옥,양원일,박종안 朝鮮大學校 電子情報通信硏究所 2004 電子情報通信硏究所論文集 Vol.7 No.2

본 연구에서는 관절 내시경 시스템 개발을 목표로 임상 교수들의 조언과 사용자의 편의를 우선으로 하는 PC기반 GUI 형태의 관절 내시경 시스템 설계에 초점을 맞추어 연구하였다. 관절 내시경 시스템의 성능 향상을 위한 모듈 설계하여 검증을 통한 시험 및 시뮬레이션 분석을 하였다. 또한 임상 교수의 관절 내시경 시스템 개발 참여로 사용자 중심의 편리한 시스템 구성 및 관련 H/W 및 S/W 기술 축적뿐만 아니라 PC기반 GUI 형태의 윈도우 S/W 개발로 해외 시장개척을 위한 경쟁력이 강화될 것으로 기대된다.

수열합성법에 의한 MLCC용 구형 니켈분말 제조

원창환,이종현,원형일,이혁희 대한금속ᆞ재료학회 2006 대한금속·재료학회지 Vol.44 No.3

자궁탈의 임상적 고찰

김동원,노형균,안태규,최상준,송창훈,정혁 조선대학교 부설 의학연구소 1999 The Medical Journal of Chosun University Vol.24 No.1

The purpose of this study was to evaluate clinical aspects of prolape uteri. This clinical and statistical study was attempted to analyze 369 cases of uterine prolapse(328 cases -operated, the other cases - not operated) from Jan. 1994 to Dec. 1998 at the Department of Obstetrics and Gynecology, Chosun University Hospital. The results were as follows. 1. The incidences of uterine prolapse was 0.62% of the total admitted gynecologic patients during the study period. 2. Age distribution at the time of operation showed that 184 cases(25.6%) were 60 to 65 years of age, and 62 cases(18.2%) were 56 to 60 years of age. 3. Age distribution at the time of development of prolapse uteri showed that 134 cases(36.3%) were 21 to 30 years of age, 126 cases(34.1%) were 31 to 40 years of age. 4. 228 cases(61.7%) were those who had suffered from uterine prolapse for more 11 years and the mean durations were 15.6 years. 5. The degree of prolapse uteri showed that 281 cases(76.1%) were 3rd degree and 61 cases(16.5%) were 2nd degree. 6. The parity showed that 297 cases(80.2%) were over 4 times and 2 cases(0.27%) was nullipara. 7. The delivery place was at home in 318 cases(86.1%) and in hospital in 51 cases(13.9%). 8. The main symptoms comprised prolapse in 311 cases(84.2%), urinary frequency in 259 cases(70.1%), and bearing down sensation in 242 cases (65.8%). 9. An operation in 328 cases was carried out of 369 cases of prolapse uteri, 301 cases were treated by the vaginal hysterectomy with either anterior &osterior repair or posterior repair, 23 cases were treated by anterior &osterior repair. 10. The postoperative complications were urinary tract infection in 7 cases(2.1%), urinary retention in 4 cases(1.2%), vaginal vault prolapse in 2 cases(0.6%). 11. The indwelling foley catheter was kept for 7 days in 279 cases and the average postoperative hospitalization was around 9 days. 12. The postoperative pathologic findings were chronic cervicitis in 211 cases(67.8%), squamous metaplasia of the cervical gland in 98 cases(31.5%), adenomyosis in 69 cases, leiomyoma in 47 cases, and dysplasia of cervix, cervical polyp, endometrial polyp were also resulted. In conclusion, clinical features of uterine prolapse were studied. The clinical evaluation of uterine prolapse include age, parity, degree of prolapse, delivery site, age of onset, symptomatology, type of operation, complications, the results of histopathological examinations. Further study is necessary before these aspects can be implicated in the clinical evaluation of uterine prolapse.

클로르헥시딘 바니쉬의 적용이 교정용 브라켓의 전단접착강도에 미치는 영향

임동혁,김태우,장영일,남동석,양원식,백승학 대한치과교정학회 2000 대한치과교정학회지 Vol.30 No.2

본 연구의 목적은 클로르헥시딘 처리가 교정용 브라켓의 전단접착강도와 탈락 양상에 미치는 영향을 비교하는 것이다. 실험군으로 4주간 4회의 클로르헥시딘 바니쉬를 도포한 22개의 사람 소구치를 선택하였고, 대조군으로 아무 처리도 하지 않은 22개의 사람 소구치를 선택하였다. 모든 치아는 37%의 phosphoric acid gel로 부식시키고 교정용 브라켓을 같은 조건으로 부착시켰다. 전단접착강도의 측정을 위해 Instron universal testing machine(model 4466)을 이용하였고, 법랑질과 브라켓 표면은 SEM으로 관찰하였다. 결과의 분석은 t-test를 이용하였으며 결과는 다음과 같다. 1.클로르헥시딘의 법랑질 처리는 전단접착강도에 영향을 미치지 않았다. 2.클로르헥시딘으로 법랑질을 처리한 경우와 그렇지 않는 경우에 브라켓 탈락 양상에 차이가 없었다. 따라서, 클로르헥시딘으로 법랑질을 처리하여도 브라켓 접착에 유해한 작용이 없었고, 따라서 임상사용에 적합하다고 생각된다. The purpose of this study was to determine whether the application of chlorhexidine varnish affects the shear bond strength and failure pattern of orthodontic brackets or not. The experimental group consisted of 22 human premolars which extracted after chlorhexidine vanish application(4 times for 1 week interval) in vivo, and the control group consisted of 22 human premolars which extracted without any pre-treatment. After all teeth were etched with 37% phosphoric acid gel, metal orthodontic brackets (Q-3002, RMO, USA) were bonded to each tooth using auto-polymerizing orthodontic resin (Ortho-One, Bisco, USA) with the same bonding procedure. The shear bond strength was measured with Instron universal testing machine (model 4466, Instron Ltd., England), and the failure pattern of each bracket was examined with Scanning Electron Microscope (SM 840A, JEOL, Japan). The data were analysed statistically with t-test. The results were as follows : 1.Application of chlorhexidine varnish had no significant effect on the shear bond strength of the orthodontic bracket. 2.There was no significant difference in the failure pattern of orthodontic bracket between the experimental group and the control group.

광섬유를 이용한 고감도 압력센서의 개발

김창원,권대혁,김진섭,이정희,손병기 경북대학교 센서기술연구소 1995 연차보고서 Vol.1995 No.-

KOH 수용액을 이용하여 실리콘 식각공정기술을 확립하였으며, 이를 이용하여 실리콘 기판 위에 스트레스 균형이 이루어진 150 ㎚-Si_3N_4/300 ㎚-SiO_2/150 ㎚-Si_3N_4 두께를 가지는 구조의 평탄한 3층 유전체 멤브레인을 제작하였다. 본 실험에서 사용되는 파장인 1.3 ㎛ 근방에서 다이아프레임의 광투과도는 약 50 %로 광반사막으로 사용이 불가능하였다. 따라서, 다이아프레임 뒷면에 약 1000 Å의 금을 증착하여 N/O/N/Au박막의 광투과도를 수 %정도로 감소시킴으로써, 센서의 광반사막으로 사용할 수 있었다. source fiber를 단일모드로 했을 때 다이아프레임의 크기에 따라 감도는 각각 0.52㎻/torr(3×3 ㎟), 0.65 ㎻/torr(4×4 ㎟), 0.77 ㎻/torr(5×5 ㎟)였다. 광손실을 최소화하기 위해 광전송용 다모드 광섬유를 사용하였을 때는, 2×2 ㎟의 다이아프레임의 크기에 대해 0∼800 torr의 넓은 측정범위에서 거의 선형적인 압력특성을 나타내었다. Using KOH solution, silicon etching technology has been established and stress-balanced flat 600 ㎚ thick triple dielectric membrane(150 ㎚-Si_3N_4/300 ㎚-SiO_2/150 ㎚-Si_3N_4) on silicon substrate has been fabricated. At the wavelength of the sensor light source near 1.3 ㎛, the optical transmittance of the diaphragm was about 50 %, it was impossible to be used as a reflecting film. To decrease to a few percents, the back-side of the diaphragm was deposited 1,000 Å thick gold layer, which is sufficient enough to be used as a light reflection layer of the sensor. When was used 8/126 ㎛ single-mode fiber, the respective sensitivities for diaphragm size were 0.52 ㎻/torr(3×3 ㎟), 0.65 ㎻/torr(4×4 ㎟), 0.77 ㎻/torr(5×5 ㎟). When was used 62/126 ㎛ multi-mode fiber for the light transmission to minimize optical loss, the pressure characteristics was showed almost linearly curve in a wide pressure range, 0 torr∼800 torr, for the 2×2 ㎟ diaphragm in dimensions.