Soft, adhesive and conductive composite for electroencephalogram signal quality improvement

Jeong E Jin,Seohyeon Kim,Hyeji Yu,Keyong Nam Lee,Young Rag Do,Seung Min Lee 대한의용생체공학회 2023 Biomedical Engineering Letters (BMEL) Vol.13 No.3

Since electroencephalogram (EEG) is a very small electrical signal from the brain, it is very vulnerable to external noise ormotion artifact, making it difficult to measure. Therefore, despite the excellent convenience of dry electrodes, wet electrodeshave been used. To solve this problem, self-adhesive and conductive composites using carbon nanotubes (CNTs) in adhesivepolydimethylsiloxane (aPDMS), which can have the advantages of both dry and wet electrodes, have been developed bymixing them uniformly with methyl group-terminated PDMS. The CNT/aPDMS composite has a low Young's modulus,penetrates the skin well, has a high contact area, and excellent adhesion and conductivity, so the signal quality is enhanced. As a result of the EEG measurement test, although it was a dry electrode, results comparable to those of a wet electrode wereobtained in terms of impedance and motion noise. It also shows excellent biocompatibility in a human fibroblast cell test anda week-long skin reaction test, so it can measure EEG with high signal quality for a long period of time.

Continuous Wave of Condensation Technique으로 근관충전시 치근면 온도상승 분석

김영주,황윤찬,김선호,황인남,최보영,정영진,정우남,오원만 전남대학교 치의학연구소 2003 구강과학 Vol.15 No.4

This study was conducted to evaluate safety to the supporting tissues of the root while the root canal is obturated using continuous wave of condensation technique. A extracted maxillary central incisor was prepared for repeated canal obturation. After conventional access opening, working length was then established to the point 1㎜ from anatomical root apex. The root canal was prepared with GT rotary Ni-Ti file (Dentsply Maillefer, Switzerland). Five thermocouples (Onega Engineering Inc., USA) were placed at 2㎜ increments on one side beginning 1㎜ from the anatomical root apex and the other five thermocouples at 2㎜ increments on the other side beginning 2㎜ from it. For obturation, a nonstandardized medium size gutta-percha cone and a ML Buchanan plugger (Analytic technologies, USA) were selected. After drying of root canal, AH 26 root canal sealer (Dentsply Detrey, Germany) was applied on the wall of the root canal. Baseline temperature was measured on the root surface. The ML size plugger was preheated for 2seconds and then the real temperature of it was recorded before insertion into the root canal. The root canal was obturated with continuous wave of condensation technique as described by Buchanan. The root surface temperature was recorded during obturation and it was performed ten times at each of the following temperature settings: 150℃, 200℃, 250℃ and 300℃. After completion of the temperature recording, the dentinal-cementum thickness at each sites where thermocouples were attached was measured. The data were analyzed using one-way ANOVA followed by Scheffe's test and linear regression test. The results were as follows. 1. When the temperature was set at 150℃, 200℃, 250℃ and 300℃ on the digital display of System B HeatSource, the real temperature of the plugger at the 1㎜ point from the tip revealed 130.82±2.96℃, 158.00±5.26℃, 215.92±6.91℃ and 249.88±3.65℃ respectively. 2. The position of 8 ㎜ from the anatomical apex showed the highest temperature increase at each temperature settings and it was significantly higher than those of other positions (p<0.01). The temperature rise was constantly increased toward coronal portion from apex of the root. 3. The maximum temperature increase on the root surface was 2.37±0.09℃ at 150℃ setting, 3.11±0.12℃ at 200℃ setting, 3.93± 0.09℃ at 250℃ setting and 5.69± 0.15℃ at 300℃ setting. These results suggest that it be relatively kind to the supporting tissues of the root that the root canal is obturated using continuous wave of condensation technique at 150℃, 200℃, 250℃ and 300℃ temperature settings on digital display of System B HeatSource.

Continuous Wave of Condensation Technique으로 근관충전시 치근면 온도상승 분석

김영주,황윤찬,김선호,황인남,최보영,정영진,정우남,오원만 大韓齒科保存學會 2003 Restorative Dentistry & Endodontics Vol.28 No.4

This study was conducted to evaluate the temperature rise on the root surface while the root canal is being obturated using continuous wave of condensation technique. Maxillary central incisor was prepared for repeated canal obturation. Ten thermocouples (Omega Engineering Inc., Stanford, USA) were placed at 1mm increment from the anatomical root apex. The real temperature of Buchanan plugger was recorded before insertion into the root canal. The root canal was obturated with continuous wave of condensation technique as described by Buchanan and the root surface temperature was recorded during obturation at 150℃, 200℃, 250℃ and 300℃ temperature settings of System B HeatSource (Model 1005, Analytic technologies, Redmond, WA, USA). After completion of the temperature recording, the dentinal-cementum thickness at each sites was measured. The data were analyzed using one-way ANOVA followed by Scheffe's test and linear regression test. The results were as follows. 1. When the temperature was set at 150℃, 200℃, 250℃ and 300℃ on the digital display of System B HeatSource, the real temperature of the plugger at the 1mm point from the tip revealed 130.82±2.96℃ 158.00±5.26℃, 215.93±6.91℃ and 249.88±3.65℃ respectively. 2. The position of 8 mm from the anatomical apex showed the highest temperature increase at each temperature settings and it was significantly higher than those of other positions (p<0.01). The temperature rise was constantly increased toward coronal portion from apex of the root. 3. The maximum temperature increase on the root surface was 2.37±0.09℃ at 150℃ setting, 3.11±0.12℃ at 200℃ setting, 3.93±0.09℃ at 250℃ setting and 5.69±0.15℃ at 300℃ setting respectively. These results suggest that it be relatively kind to the supporting tissues of the root that the root canal is obturated using continuous wave of condensation technique at 150℃, 200℃, 250℃ and 300℃ temperature settings on digital temperature display of System B HeatSource.

남성화를 보이는 여성에서 발견된 난소의 Steroid Cell Tumor 1예

조인호,정대훈,박영미,서영진,손영실,정철회,강영미,정수전,김영남,이경복,성문수,김기태 인제대학교 2006 仁濟醫學 Vol.27 No.-

Steroid cell tumor is a rare ovarian sex cord-stromal tumor which accounts for 0.1% of all ovarian tumors. Until now, only 4 cases have been reported in domestic literatures. Steroid cell tumor often secrets testosterone and presents virilization in adult women or precocious puberty in children. Treatment is often performed by surgical removal, adjuvant chemotherapy and radiation, but completely accepted treatment was not existed. We experienced a case of steroid cell tumor, which was manifested by typical virilization in a 43-year old patient, who was previously performed hysterectomy and unilateral oophorectomy. So, we present with a brief review of the literatures.

40세 이하 관상동맥 질환자에서 장기적 임상 관찰

이승욱,정명호,박종철,박형욱,조상희,김원,김계훈,이상현,강경태,조장현,김남호,김건형,안영근,조정관,박종춘,강정채 全南大醫大 2001 전남의대학술지 Vol.37 No.2

대동맥 협착증과 동반된 출혈성 위장관 동정맥 기형에서 Estrogen-Progesterone 치료 1예

김도연,김화정,김효정,남준식,박수영,박영미,신정은,주미순,황민규,정혜경,손혜영,이선영,이한주 大韓消化器內視鏡學會 1999 Clinical Endoscopy Vol.19 No.부록2

초·중·고등학교 학생·학부모·일반교사의 보건교육 영역별 요구도와 보건교육

윤순녕,김영임,최정명,조희순,김영희,박영남,오경순,이분옥,조선녀,조소영,한선희,하영미 韓國學校保健學會 2005 韓國學校保健學會誌 Vol.18 No.1

Purpose: The purpose of this study was to identify the needs of health education in students, their parents and teachers in the elementary, middle and high schools and the current situation of health education class. Method: The subjects of this study were a total of 9450 persons including students, their parents and teachers from 279 schools throughout the country. They were selected through convenient sampling. Data were analyzed through x^(2)­test and ANOVA. Result: Students, their parents and teachers replied that 18 dimensions of health education class (DHEC) are necessary. The four DHEC - healthier life style, sex education, mental health and safety education - showed high educational needs in students, their parents, and teacher. High school students had higher educational need of 'symptom management for daily living' than elementary and middle school students. Students, their parents and teachers in elementary school had higher educational needs of 17 DHEC that those in middle and high school. The percentages of schools with health education class taught by health teachers were 99.2%, 75.5% and 66.0% respectively in elementary, middle and high schools. Health education was given mainly using physical education classes at elementary schools, and creative class hours at middle and high schools. In general, health education took 1-3 hours per week at elementary schools, and less than an hour at middle and high schools. Conclusion: Therefore, based on the results, systematic health education class should begin from elementary school to meet the need of health education in students, their parents and teachers, and further study should be made on the number of hours required and the amount of contents of 18 DHEC.

초·중·고등학교 학생, 학부모, 일반교사의 보건교육 요구

윤순녕,김영임,최정명,조희순,김영희,박영남,오경순,이분옥,조선녀,조소영,한선희,하영미 韓國學校保健學會 2004 韓國學校保健學會誌 Vol.17 No.2

Purpose : The purpose of this study was to identify needs of health education of the students, parents, general teachers, and health teacher of the elementary, middle, and high schools. Method : 279 schools of elementary, middle, and high school were sampled nonproportionally during the period from June 28 to July 26, 2004 . The data were collected by the questionnaire from 1,888 students, 1,876 parents, 1,695 general teachers, 279 health teachers. A frequency, % and χ2-test were used to analysis by SAS program. Result : 1. It showed that 98.1% of elementary school students, 92.3% of middle school students, 89.6% of high school students answered that they need health education. The most of students, parents, and general teachers had high interests in health education. 2. In the case of students, main causes of needs of health education was 'to prevent diseases or accidents''. But parents answered that it was 'to build up a healthier behavior'. General teachers answered that it was 'more effective systematic and continuous health education'. 3. Over 80% of students, parents, and general teachers about the question of who qualified person is to teach health education as a regular class responded that health teacher is available. Especially 93% of elementary school students answered like that. 4. The most of students, parents, and general teachers answered that health education in the classroom is favorable 1 to 2 hours per week. Conclusion : As results of the study , the majority of students, parents, general teachers agreed needs of health education. Therefore, on the basis of this study, systematic and continuous health education is necessary. Additionally the establishment of independent health subject is required certainly.

Thermocouple을 이용한 Buchanan Plugger 표면의 온도상승 분석

조진숙,황윤찬,김선호,황인남,최보영,정영진,정우남,오원만 전남대학교 치의학연구소 2003 구강과학 Vol.15 No.4

This study was performed to confirm the actual temperature rise on the surface of Buchanan plugger by evaluating the temperature rise on the surface of it, the peak temperature of pluggers of various size using thermocouple. The heat carrier system 'System B Heatsource' (Model 1005, Analytic Technologies, USA) and the Buchanan pluggers of F, FM, M and ML sizes are used for this study. The temperature was set to 200 which Dr. Buchanan's "Continuous wave of condensation" technique recommended on digital display and the power level on it was set to 10. The touch mode was used. Five thermocouples were placed in direct contact with the surface of each size of Buchanan's pluggers at 1 ㎜ increments from the tip to the 4 ㎜ length of shank. Each thermocouple was secured with cyanoacrylate adhesive and orthodontic resin block. The two wire leads of each thermocouple were connected to the appropriate channels of Data Logger. This was configured to simultaneously record input from the five thermocouples. The heat control spring was touched for 1, 2, 3, 4 and 5 seconds, and the temperature rise on the surface of the pluggers were measured at 1 sec intervals for more than 5 seconds with an accuracy of 0.01. Ten trials was determined for each plugger. The average of temperature rise and standard deviation was calculated for each size of plugger. The data were statistically analyzed by one-way ANOVA to determine their significance. The results as follows. 1. The position at which the temperature peaked was approximately at 1∼2㎜ far from the tip of Buchanan plugger (p<0.01). 2. The peak temperature was 215.25±2.28℃ in F plugger, 185.94±2.19℃ in FM plugger, 169.51±9.12℃ in M plugger, and 160.79±1.27℃ in ML plugger and the peak temperature was highest in F type and followed by, in descending order, FM type, M type. ML type showed the lowest peak temperature (p<0.01). This results suggest that the actual temperature on the surface of the pluggers does not correlate well with the temperature set on digital display. Heat concentrates around the tip. The larger plugger reveals lower temperature rise relatively.

고령자 남녀와 20대 남녀에 있어서 다양한 등속수축중 최대 모멘트의 비교

金智源(Ji-Won Kim),金相佑(Sang-Woo Kim),文基旭(Ki-Wook Moon),嚴光文(Gwang-Moon Eom),李泳揆(Young-Gyu Lee),南貞淑(Jung-Sook Nam),朴寬龍(Kwan-Yong Park),金耀翰(Yo-Han Kim),洪廷和(Jeong-Hwa Hong),朴炳奎(Bung-Kyu Park) 대한전기학회 2008 전기학회논문지 Vol.57 No.10

In this paper, we investigated the maximum ankle joint plantarflexion moment (MPM) of young and elderly subjects during various modes of isokinetic contractions with special interest in the elderly females who were reported to have higher fall rate than the elderly males. Subjects include the young subjects (14 males: 22.7±2.5yrs, 13 females: 20.5±1.3yrs) and the elderly subjects (17 males: 65.8±10.5yrs, 26 females: 71.4±5.2yrs). The MPM was normalized by each subject's body weight. The MPM of elderly females was the weakest among the groups, particularly, at the eccentric contractions. The male-to-female ratio of MPM was greater in the elderly than in the young and the young-to-elderly ratio of MPM was greater in female than in male, both during the eccentric contractions. The result suggests that the decreased muscle force per body weight, especially at the eccentric contraction, may be one reason for the more frequent fall of the elderly female than the elderly male.