Comparison of trophic factors changes in the hippocampal CA1 region between the young and adult gerbil induced by transient cerebral ischemia.

Yan, Bing Chun,Park, Joon Ha,Kim, Sung Koo,Choi, Jung Hoon,Lee, Choong Hyun,Yoo, Ki-Yeon,Kwon, Young-Geun,Kim, Young-Myeong,Kim, Jong-Dai,Won, Moo-Ho Kluwer Academic/Plenum Publishers 2012 Cellular and molecular neurobiology Vol.32 No.8

<P>In the present study, we investigated neuronal death/damage in the gerbil hippocampal CA1 region (CA1) and compared changes in some trophic factors, such as brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF) and vascular endothelial growth factor (VEGF), in the CA1 between the adult and young gerbils after 5 min of transient cerebral ischemia. Most of pyramidal neurons (89%) were damaged 4 days after ischemia-reperfusion (I-R) in the adult; however, in the young, about 59% of pyramidal neurons were damaged 7 days after I-R. The immunoreactivity and levels of BDNF and VEGF, not GDNF, in the CA1 of the normal young were lower than those in the normal adult. Four days after I-R in the adult group, the immunoreactivity and levels of BDNF and VEGF were distinctively decreased, and the immunoreactivity and level of GDNF were increased. However, in the young group, all of their immunoreactivities and levels were much higher than those in the normal young group. From 7 days after I-R, all the immunoreactivities and levels were apparently decreased compared to those of the normal adult and young. In brief, we confirmed our recent finding: more delayed and less neuronal death occurred in the young following I-R, and we newly found that the immunoreactivities of trophic factors, such as BDNF, GDNF, and VEGF, in the stratum pyramidale of the CA1 in the young gerbil were much higher than those in the adult gerbil 4 days after transient cerebral ischemia.</P>

Relationship between Meteorological Elements and Yield of Hot Pepper in Yeosu Area of Korea

Kwon,Byung-Sun,Choi,Seong-Kyu,Shin,Jeong-Sik,Shin,Jong-Sup,Shin,Dong-Young,Hwan,Kyu-Hyun,Kim,Hak-Jin,Kuk,Yong-In,Choi,Kyong-Ju 한국자원식물학회 2003 Plant Resources Vol.6 No.1

This study was conducted to investigate the relationships between yearly variations of meteorological elements and yearly variations of productivity in hot pepper. In addition, correlation coefficients among the yields and yield components were used to find out the relationships between meteorological elements and productivity. Yearly variation of the mean air temperature in May and July showed large with coefficients of variation(C.V.) of 25.0,8.9%, respectively, but the variation of the duration of sunshine in May were relative small. Yield and plant height was greatly with C.V. of 7.14,11.6%, respectively, diameter of fruit showed more or less C.V. of 2.28% and length of fruit showed less variation. Correlation coefficients between maximum temperature in period of cultivation from May and yield are positively significant at the level of 1 %. Correlation Coefficients between precipitation in period of cultivation from May to August and yield are negative significant at the level of 5 and 1 %, respectively. Correlation coefficients amount the plant height, length of fruit, diameter of fruit per plant, and seed yield were positively significant at the level of 1 %, respectively.

AN IN-SITU YOUNG'S MODULUS MEASUREMENT TECHNIQUE FOR NUCLEAR POWER PLANTS USING TIME-FREQUENCY ANALYSIS

Choi, Young-Chul,Yoon, Doo-Byung,Park, Jin-Ho,Kwon, Hyun-Sang Korean Nuclear Society 2009 Nuclear Engineering and Technology Vol.41 No.3

Elastic wave is one of the most useful tools for non-destructive tests in nuclear power plants. Since the elastic properties are indispensable for analyzing the behaviors of elastic waves, they should be predetermined within an acceptable accuracy. Nuclear power plants are exposed to harsh environmental conditions and hence the structures are degraded. It means that the Young's modulus becomes unreliable and in-situ measurement of Young's modulus is required from an engineering point of view. Young's modulus is estimated from the group velocity of propagating waves. Because the flexural wave of a plate is inherently dispersive, the group velocity is not clearly evaluated in temporal signal analysis. In order to overcome such ambiguity in estimation of group velocity, Wigner-Ville distribution as the time-frequency analysis technique was proposed and utilized. To verify the proposed method, experiments for steel and acryl plates were performed with accelerometers. The results show good estimation of the Young's modulus of two plates.

전경대원에서 발생한 결핵의 임상 양상

문창기,박상준,조민구,김영중,김소연,김윤권,정준오,안석진,김은실,서승오,김지훈,최원제,이윤영,박형기,최규영,김현근 대한감염학회 2006 감염과 화학요법 Vol.38 No.6

Background: The purpose of this study was to document the incidence and clinical characteristics of patients with tuberculosis (TB) in combat and auxiliary police, living in a group, in Korea where the incidence rate of active TB in a general population is higher than in Western countries. Materials and Methods:We retrospectively reviewed the medical records of all tuberculosis patients diagnosed at National Police Hospital from January 2002 through December 2004. Results:In 2002-2004, a total of 156 cases of tuberculosis were identified with the mean (Standard deviation) age of 20.6 (±1.0) years. Of these, 134 (85.9%) patients were registered as new cases, 11 (7.1%) as relapse, 2 (1.3%) as failure, 5 (3.1%) as treatment-after-default cases whereas 4 (2.6 %) patients were not included in any categories. Average annual new TB rate and smear-positive TB rate were 86.5/10^(5) and 17.4/10^(5) person-years, respectively. In 12 of 31 smear-positive cases, time from onset of symptoms to diagnosis was more than 30 days. Two multidrug-resistance TB cases were identified and two suspected outbreak episodes of TB had occurred during 3 years. Conclusion:There was no statistically significant difference in the incidence rate of new cases of TB between the general population aged 20 to 29 years and combat and auxiliary police in Korea. 배경 : 국내 결핵의 발생은 감소 추세에 있으나 여전히 후진국형 발생양상을 보이고 있다. 특히 집단생활을 하는 젊은이들에서 발생하는 결핵의 유행이 간헐적으로 알려지고 있어 우려를 낳고 있다. 이에 저자들은 최근 전경대원의 결핵 발병 양상에 대해 알아보고자 본 연구를 시행하였다. 재료 및 방법 : 2002년 1월부터 2004년 12월까지 3년간 경찰병원에서 결핵 진료를 받은 전경대원의 의무기록을 후향적으로 분석하여 연도별 결핵 신환발생률, 도말양성결핵 신환율, 진단 지연, 집단발병, 다제내성결핵을 조사하였다. 결과 : 연도별 결핵 신환자 수(10만명당 발생추정치)는 2002년 50명(83.6명), 2003년 42명(83.7명), 2004년 42명(93.5명)이었고 도말양성 폐결핵 신환자 수는 2002년 10명(16.7명), 2003년 11명(21.9명), 2004년 6명(13.4명)이었다. 3년간 도말양성 폐결핵 환자는 31명이 있었고 그 중 12명은 호흡기 증상 발생 30일이 지나서 진단을 받았다. 다제내성 결핵은 2명이 있었으며 결핵의 집단발병이 의심되는 사례는 2차례 있었다. 결론 : 전경대원과 20-29세 연령군 일반인의 결핵 신환발생률, 도말양성 폐결핵 발생률의 통계적으로 유의한 차이는 없었다.

Direct effectiveness of pneumococcal polysaccharide vaccine against invasive pneumococcal disease and non-bacteremic pneumococcal pneumonia in elderly population in the era of pneumococcal conjugate vaccine: A case-control study

Kim, Jong Hun,Chun, Byung Chul,Song, Joon Young,Kim, Hyo Youl,Bae, In-Gyu,Kim, Dong-Min,Choi, Young Hwa,Jun, Yoon Hee,Choi, Won Suk,Kang, Seong Hee,Kwon, Hyun Hee,Jeong, Hye Won,Kee, Sae Yoon,Hur, Jia Elsevier Ltd. 2019 Vaccine Vol. No.

<P><B>Abstract</B></P> <P><B>Background</B></P> <P>While herd effects and serotype replacement by childhood pneumococcal protein conjugated vaccines (PCVs) continues to accumulate worldwide, direct effectiveness of 23-valent pneumococcal polysaccharide vaccine (PPV23) against pneumococcal diseases in the elderly has been challenged. We estimated the direct effectiveness of PPV23 in the elderly population.</P> <P><B>Methods</B></P> <P>For a hospital-based case-control study, cases of invasive pneumococcal disease (IPD) and non-bacteremic pneumococcal pneumonia (NBPP) (adults ≥ 65 years) were identified in 14 hospitals participated in the pneumococcal surveillance program from March 2013 to October 2015, following implementation of PPV23 national immunization program (NIP) for the elderly in the Republic of Korea. Controls matched by age, sex, and hospital were selected at ratios of 1:2 (IPD) or 1:1 (NBPP). Clinical data and vaccination records were collected. Vaccine effectiveness was calculated as (1-adjusted odds ratio) × 100.</P> <P><B>Results</B></P> <P>We enrolled 148 IPD and 557 NBPP cases, and 295 IPD and 557 NBPP controls for analyses. Overall effectiveness of PPV23 against IPD was 28.5% [95% confidence interval (CI) −5.8%–51.6%] and against NBPP was 10.2% (-15.1-30.6) in all patients ≥ 65 years. However, in subgroup analysis of patients aged 65–74 years, PPV23 was protective against IPD [effectiveness 57.4% (19.4–77.5)] and against NBPP [effectiveness 35.0% (2.3–56.7)]. Furthermore, serotype-specific effectiveness of PPV23 against IPD was 90.6% (27.6–98.8) for PPV23-unique serotypes and 81.3% (38.6–94.3) for PPV23 serotypes excluding serotype 3.</P> <P><B>Conclusions</B></P> <P>This study indicates that PPV23 with broad serotype coverage might be beneficial in preventing IPD and NBPP due to non-PCV13 serotypes in the young-elderly, with potentially increasing effectiveness in the setting of childhood PCV NIP.</P> <P><B>Highlights</B></P> <P> <UL> <LI> National immunization program for PPV23 for the elderly was implemented in Korea. </LI> <LI> PPV23 was effective against IPD and NBPP for young elderly patients aged 65–74. </LI> <LI> Effectiveness of PPV23 against IPD was higher for PPV23 unique serotypes. </LI> <LI> PPV23 was non-protective against IPD caused by PCV13 serotypes. </LI> </UL> </P>

1회선 분기점을 갖는 병행 2회선 송전선로 고장점 표정 알고리즘

權寧珍,美想熙,李承宰,崔勉松 明知大學校 産業技術硏究所 2002 産業技術硏究所論文集 Vol.21 No.-

This paper presents a fault location algorithm of a single phase-to-ground fault on a parallel transmission line which contains a teed circuit. The method uses only the local end voltage and current signals. Zero sequence currents of other lines are calculated by distribution factors. Instead of zero sequence current, negative sequence current is used to remove the effect of load current and to calculate the voltage of a fault resistance. There are three distance equations in this algorithm. One of them is to calculate inner part fault location without teed circuit and another equation is for outer part fault location without teed circuit and the other is to calculate inner part fault location with teed circuit. Correct fault distance is selected by the condition of each solution. Extensive simulation studies using EMTP have verified that the proposed algorithm can calculate an accurate fault distance in spite of effects of various error sources.

치주질환 심도에 따른 치아동요도와 교합력의 상관관계에 관한 연구

최조우,이만섭,권영혁 慶熙大學校 齒科大學 1993 慶熙齒大論文集 Vol.15 No.1

The purpose of this study was to investigate the change of tooth mobility and bite force according to periodontal disease severity. Tooth mobility and biting force due to change of viscoelastic property of periodontium were influenced by inflammation of periodontal tissue. 30 patients participated in this study, the periodontal disease severity is evaluated with SBI and attachment loss. SBI and attachment loss were examined by periodontal probe. Tooth mobility was tested two times to each tooth using periotest (Siemens Co, Germany) and bite force was evaluated with MPM-3000 (Nihon Kohden Co, Japan Statistical analysis was applied to correlation (r2) and regression analysis. The obtained results were as follows 1. As the attachment loss increased, tooth mobility increased with significance, and they had highly positive correlation (r-2=0.68) on entire dentition. 2. As the SBI increased, tooth mobility increased with significance, and they had positive correlation (r2=0.37) on entire dentition. 3. As the attachment loss increased, bite force decreased with significance, and they had highly negative correlation (r2=0.42) on maxillary anterior dentition but low negative correlation (r2=0.20) on the other portion of dentition. 4. As the SBI increased, bite force decreased with significance, and they had highly negative correlation (r-2=0.31) on maxillary anterior dentition but low negative correlation (rz=0.16) on the other portion of dentition. 5. As tooth mobility increased, bite force decreased with significance, and they had highly negative correlation (r2=0.32) on maxillary anterior dentition but low negative correlation (r2=0.16) on the other portion of dentition.

PZT께 압전 세라믹스의 제조 및 기계적 특성에 관한 연구

崔永根,權鍾完 慶一大學校 1993 論文集 Vol.9 No.1

Densification behavior, microstructural evolution and mechanical properties of hot-pressed specimens using PZT ceramics with PbO additive were studied, and bulk density, microstructure, mechanical properties were investigated for sintering time. Fracture toughness of the spections containing 1mol% PbO was increased as the hot-pressing temperature up to 1080℃ and maximum value was 1.60MN/m??, while fracture toughness of the specimens containing 2mol% PbO was decreased. The enhanced fracture toughness by PbO is probably due to the crack deflection along the boundaries of the elongated grains. Vicker's hardness of the specimens was in the range of 270-320Kgf/mm² and was decreased due to the incrasing of pore according to PbO addition. As the sintering time becomes longer, fracture toughness was gradually decreased for the the increasing of grain size and vicker's hardness was shown the linear increasing lue to increase of density.

소형환편기 자동화기술개발에 관한 연구

최세환,장승호,허유,박준희,권영하 경희대학교 산학협력기술연구원 1995 산학협력기술연구논문집 Vol.1 No.-

소형환편기의 자동화기술을 위해 편환을 이동시킬 수 있는 편침과 cam을 편환이송용 장치를 고안하였다. 위편기의 편환이송 mechanism을 해석하고 소형환편기의 물리적 모사를 통해 편침과 cam의 형상을 최적화하였다. 편환이송장치를 사용하여 편물에 다양한 조직을 편성할 수 있는 편기의 개발이 가능하도록 하였다. The latch needle and cam are newly designed and manufactured to transfer the loop for automation of small circular knitting machine. The loop transfer mechanism is analized by the simulation of needle motion on the V-bed flat knitting machine to which optimum designed cam is attached. This loop transfer mechanism can be applied to small circular knitting machine for automation and variable knitted structure.

황산이온의 토양 흡착에 관한 연구

권영식,최찬섭 연세대학교 보건과학연구소 1997 보건과학논집 Vol.7 No.-