미세각막절개도 헤드의 선택을 통한 맞춤식각막절개방식의 라식

강민호,송유미,강성민,박영숙,최철영,이윤정,이병로.Min Ho Kang. M.D.. Yoo Mi Song. M.D.. Sung Min Kang. M.D.. Young Sook Park. M.D.. Chul Young Choi. M.D.. Yoon Jung Lee. M.D.. Byung Ro Lee. M.D. 대한안과학회 2006 대한안과학회지 Vol.47 No.2

Purpose: To compare the intraoperative and postoperative complication rates and visual outcomes with M2 130 head (thick flap group) and M2 110 head (thin flap group). Methods: One-hundred-ninety-five eyes of 104 patients who underwent LASIK with the Moria M2 microkeratome and Allegretto-wave laser were reviewed retrospectively. Selection of M2 heads was based on preoperative pachymetry and estimated ablation depth. Intraoperative and postoperative flap-related complications, mean postoperative uncorrected visual acuity (UCVA), and mean spherical equivalent (MSE) were evaluated and compared. Results: Mean follow-up was 8.1 months. The number of eyes, preoperative MSE and mean corneal thickness of M2 130 were 115, -4.04±1.63diopter (D) and 549.40±39.16??m, and 85, -6.61±3.43D and 525.16±24.53 ?m, respectively, in the 110 head group. Mean UCVA and MSE at postoperative 1 week, 3 months and 6 months were 1.00±0.18, -0.26±0.49D; 1.07±0.68, -0.40±0.51D; and 1.01±0.22, -0.51±0.50D, respectively, in the 130 head group, and 0.90±0.23, -0.46±1.02D; 0.91±0.23, -0.67±0.79D; 0.85±0.46, -0.75±0.88D, respectively, in the 110 head group. There were no significant differences in intraoperative and postoperative flap-related complication rates between the two groups (p=0.316). There were no statistically significant differences in postoperative mean UCVA or MSE between the two groups (p>0.05), except for MSE at the third and sixth postoperative months (p=0.005, 0.013). Conclusions: Proper selection of M2 heads by preoperative pachymetry allowed for an adequate residual stroma bed with good visual outcome. Utilizing one single microkeratome and switching between two heads was advantageous and cost-effective.

RF 스위치 적용을 위한 박막 PZT 엑추에이터의 d<SUB>31</SUB> 구동과 d<SUB>33</SUB> 구동 특성 비교

신민재(M. J. Shin),서영호(Y. H. Seo),최두선(D-S. Choi),황경현(K-H. Hwang) 한국정밀공학회 2006 한국정밀공학회 학술발표대회 논문집 Vol.2006 No.5월

In this work, we present the comparison between d<SUB>31</SUB> and d<SUB>33</SUB> mode characterization using the PZT micro-actuator for large displacement. The PZT micro-actuator consisted of Si, PZT, and Pt layer on SOI wafer. The electrode shapes were laminated and interdigitated for d<SUB>31</SUB> and d<SUB>33</SUB> mode, respectively. In order to characterize the actuation mode, we measured the displacement using laser interferometer. The maximum displacement of d<SUB>31</SUB> mode was 12.2㎛ at 10V, the actuation characterization of d<SUB>31</SUB> was better than that of d<SUB>33</SUB> mode. We estimated that displacement of d<SUB>33</SUB> mode would be larger than that of d<SUB>31</SUB> above 30V.

세관 양광주 방전에서 플라즈마 확산의 완전 해

김동준,정종문,김정현,황하청,정재윤,조윤희,임현교,구제환,최은하,조광섭,Jin, D.J.,Jeong, J.M.,Kim, J.H.,Hwang, H.C.,Chung, J.Y.,Cho, Y.H.,Lim, H.K.,Koo, J.H.,Choi, E.H.,Cho, G.S. 한국진공학회 2010 Applied Science and Convergence Technology Vol.19 No.1

관경이 수 mm인 세관 램프 내부에서 플라즈마의 확산을 조사하기 위하여 이극성(ambipolar) 확산방정식을 해하였다. 반경 방향의 확산에 의한 유리관 벽에서의 플라즈마 소멸 특성시간은 $\tau_r\;=\;(r_0/2.4)^2/D_a$로 주어진다. 반경 $r_0{\sim}1\;mm$이고 이극성 확산계수 $D_a{\sim}0.01\;m^2/s$ 이면, $\tau_r{\sim}17\;{\mu}s$이다. 이는 램프의 교류전원 구동에서 플라즈마를 유지하기 위한 구동 최소 주파수 ~30 kHz에 해당한다. 고전압이 인가되는 전극부에 발생한 고밀도의 플라즈마가 양광주로 확산되는 특성시간은 $\tau_z{\sim}0.1\;s$이다. 고밀도 플라즈마 경계에서의 시간에 대한 확산속도는 $t{\sim}10^{-6}\;s$일 때 $u_D{\sim}10^2\;m/s$이고, $t{\sim}10^{-3}\;s$이면 그 속도는 $u_D{\sim}1\;m/s$로 느려진다. 따라서 램프 길이 ~1 m에 대하여 전극부에서 생성된 고밀도 플라즈마가 양광주 전체로 확산되는 시간은 수 초가 걸린다. The ambipolar diffusion equation has been solved in a fine-tube lamp of a few mm in diameter. In the diffusion of radial direction, the plasma diffuses and vanishes away at the glass wall by recombination with the characteristic time of plasma loss is given by $\tau_r\;=\;(r_0/2.4)^2/D_a$. With the radius $r_0{\sim}1\;mm$ and the ambipolar diffusion coefficient $D_a{\sim}0.01\;m^2/s$, the vanishing time is calculated $\tau_r{\sim}10\;{\mu}s$ which corresponds to the least value of frequency 30 kHz for the sustaining the plasma in the operation of high voltage AC-power. In the diffusion of longitudinal z-direction, a high density plasma generated at the area of a high voltage electrode, diffuses into the positive column with the characteristic time $\tau_z{\sim}0.1\;s$. The plasma diffusion velocity at the boundary of high density plasma is $u_D{\sim}10^2\;m/s$ at the time $t{\sim}10^{-6}$ s and the diffusion velocity becomes slow as $u_D{\sim}1\;m/s$ at $t{\sim}10^{-3}\;s$. Therefore, for the long lamp of 1 m, it takes about several seconds for the high density plasma at the area of electrode to diffuse through the whole positive column space.

d-pinitol regulates Th1/Th2 balance via suppressing Th2 immune response in ovalbumin-induced asthma

Lee, J.S.,Lee, C.M.,Jeong, Y.I.,Jung, I.D.,Kim, B.H.,Seong, E.Y.,Kim, J.I.,Choi, I.W.,Chung, H.Y.,Park, Y.M. North-Holland Pub ; Elsevier Science Ltd 2007 FEBS letters Vol.581 No.1

d-pinitol has been demonstrated to exert insulin-like and anti-inflammatory activities. However, its anti-allergic effect in the Th1/Th2 immune response is poorly understood. Recently, it was shown that T-bet and GATA-3 are master Th1 and Th2 regulatory transcription factors. In this study, we have attempted to determine whether d-pinitol regulates Th1/Th2 cytokine production, T-bet and GATA-3 gene expression in OVA-induced asthma model mice. We also examined to ascertain whether d-pinitol could influence eosinophil peroxidase (EPO) activity. After being sensitized and challenged with ovalbumin (OVA) showed typical asthmatic reactions. These reactions included an increase in the number of eosinophils in bronchoalveolar lavage (BAL) fluid, an increase in inflammatory cell infiltration into the lung tissue around blood vessels and airways, airway luminal narrowing, and the development of airway hyper-responsiveness (AHR). The administration of d-pinitol before the last airway OVA challenge resulted in a significant inhibition of all asthmatic reactions. Accordingly, this study may provide evidence that d-pinitol plays a critical role in the amelioration of the pathogenetic process of asthma in mice. These findings provide new insight into the immunopharmacological role of d-pinitol in terms of its effects in a murine model of asthma, and also broaden current perspectives in our understanding of the immunopharmacological functions of d-pinitol.

성인의 급성 심장사에서 정상 심장례의 분석

강신몽,이원태,이한영,서중석,최영식,권일훈,정낙은 大韓法醫學會 2000 대한법의학회지 Vol.24 No.2

The authors analysed 53 cases of sudden cardiac death(SCD) without prominent structural abnormalies of heart out of witnessed 300 cases. Thirty four cases were associated with sleep and 19 with activity or rest. Twenty one cases were classified as having normal hearts, and the rest as structurally mild abnormal ones. Male was predominant, and almost of the victims were suffered in their twenties or thirties. All cases collapsed instantaneously or in very short time with various and not specific terminal symptoms. Inducing or trigger factors are not clarified in almost of the cases. Mechanisms or causes of death could not be defined clearly. We concluded that careful heart examination with detailed clinical history under the appropriate postmortem investigation system is only effective approach for the true mechanism and cause of death.

Valeriana officinalis extract and its main component, valerenic acid, ameliorate d-galactose-induced reductions in memory, cell proliferation, and neuroblast differentiation by reducing corticosterone levels and lipid peroxidation

Nam, S.M.,Choi, J.H.,Yoo, D.Y.,Kim, W.,Jung, H.Y.,Kim, J.W.,Kang, S.Y.,Park, J.,Kim, D.W.,Kim, W.J.,Yoon, Y.S.,Hwang, I.K. Pergamon Press ; Elsevier Science Ltd 2013 Experimental Gerontology Vol.48 No.11

Valeriana officinalis is used in herbal medicine of many cultures as mild sedatives and tranquilizers. In this study, we investigated the effects of extract from valerian root extracts and its major component, valerenic acid on memory function, cell proliferation, neuroblast differentiation, serum corticosterone, and lipid peroxidation in adult and aged mice. For the aging model, d-galactose (100mg/kg) was administered subcutaneously to 6-week-old male mice for 10weeks. At 13weeks of age, valerian root extracts (100mg/kg) or valerenic acid (340μg/kg) was administered orally to control and d-galactose-treated mice for 3weeks. The dosage of valerenic acid (340μg/kg), which is the active ingredient of valerian root extract, was determined by the content of valerenic acid in valerian root extract (3.401+/-0.066mg/g) measured by HPLC. The administration of valerian root extract and valerenic acid significantly improved the preferential exploration of new objects in novel object recognition test and the escape latency, swimming speeds, platform crossings, and spatial preference for the target quadrant in Morris water maze test compared to the d-galactose-treated mice. Cell proliferation and neuroblast differentiation were significantly decreased, while serum corticosterone level and lipid peroxidation in hippocampus were significantly increased in the d-galactose-treated group compared to that in the control group. The administration of valerian root extract significantly ameliorated these changes in the dentate gyrus of both control and d-galactose-treated groups. In addition, valerenic acid also mitigated the d-galactose-induced reduction of these changes. These results indicate that valerian root extract and valerenic acid enhance cognitive function, promote cell proliferation and neuroblast differentiation, and reduce serum corticosterone and lipid peroxidation in aged mice.

MOA-2010-BLG-073L: AN M-DWARF WITH A SUBSTELLAR COMPANION AT THE PLANET/BROWN DWARF BOUNDARY

Street, R. A.,Choi, J.-Y.,Tsapras, Y.,Han, C.,Furusawa, K.,Hundertmark, M.,Gould, A.,Sumi, T.,Bond, I. A.,Wouters, D.,Zellem, R.,Udalski, A.,Snodgrass, C.,Horne, K.,Dominik, M.,Browne, P.,Kains, N.,Br IOP Publishing 2013 The Astrophysical journal Vol.763 No.1

<P>We present an analysis of the anomalous microlensing event, MOA-2010-BLG-073, announced by the Microlensing Observations in Astrophysics survey on 2010 March 18. This event was remarkable because the source was previously known to be photometrically variable. Analyzing the pre-event source light curve, we demonstrate that it is an irregular variable over timescales >200 days. Its dereddened color, (V - I)(S),(0), is 1.221 +/- 0.051 mag, and from our lens model we derive a source radius of 14.7 +/- 1.3 R-circle dot, suggesting that it is a red giant star. We initially explored a number of purely microlensing models for the event but found a residual gradient in the data taken prior to and after the event. This is likely to be due to the variability of the source rather than part of the lensing event, so we incorporated a slope parameter in our model in order to derive the true parameters of the lensing system. We find that the lensing system has a mass ratio of q = 0.0654 +/- 0.0006. The Einstein crossing time of the event, t(E) = 44.3 +/- 0.1 days, was sufficiently long that the light curve exhibited parallax effects. In addition, the source trajectory relative to the large caustic structure allowed the orbital motion of the lens system to be detected. Combining the parallax with the Einstein radius, we were able to derive the distance to the lens, D-L = 2.8 +/- 0.4 kpc, and the masses of the lensing objects. The primary of the lens is an M-dwarf with M-L,M-1 = 0.16 +/- 0.03 M-circle dot, while the companion has M-L,M-2 = 11.0 +/- 2.0 M-J, putting it in the boundary zone between planets and brown dwarfs.</P>

Supplementation of oil-based inactivated H9N2 vaccine with M2e antigen enhances resistance against heterologous H9N2 avian influenza virus infection

Park, J.K.,Lee, D.H.,Cho, C.H.,Yuk, S.S.,To, E.O.,Kwon, J.H.,Noh, J.Y.,Kim, B.Y.,Choi, S.W.,Shim, B.S.,Song, M.K.,Lee, J.B.,Park, S.Y.,Choi, I.S.,Song, C.S. Elsevier Scientific Pub. Co 2014 Veterinary microbiology Vol.169 No.3

Avian influenza virus (AIV) subtype H9N2 has been evolving rapidly and vaccine escape variants have been reported to cause circulation of infections and economic losses. In the present study, we developed and evaluated ectodomain of the AIV matrix 2 (M2e) protein as a supplementing antigen for oil-based inactivated H9N2 vaccine to increase resistance against vaccine escape variants. AIV H9N2 M2e antigen was expressed in Escherichia coli and supplemented to inactivated H9N2 oil emulsion vaccine. Specific pathogen-free chickens received a single injection of inactivated H9N2 oil emulsion vaccines with or without M2e supplementation. At three weeks post vaccination, hemagglutination inhibition tests and enzyme-linked immunosorbent assays were performed to determine serological immune responses. Challenge study using a vaccine escape H9N2 variant was performed to evaluate the efficacy of M2e supplementation. M2e antigen supplemented in oil emulsion vaccine was highly immunogenic, and a single M2e-supplemented vaccination reduced challenge virus replication and shedding more effectively than non-supplemented vaccination.

펨토초 레이저와 미세각막절삭기를 이용한 근시교정수술에서 임상성적 비교

최은수,정희진,이경헌,Yun Su Choi,M,D,Hee Jin Jung,M,D,Kyung Hun Lee,M,D 대한안과학회 2007 대한안과학회지 Vol.48 No.8

Purpose: To compare results between in femtosecond laser and microkeratome LASIK correction of myopia Methods: We retrospectively analyzed the result of 94 eyes of 47 patients in the femtosecond group (F) and 103 eyes of 52 patients in the microkeratome group (M). All patients had undergone LASIK using either a femtosecond laser or a microkeratome for making of flap. Patients were divided into groups I (6D≤) and II (≥6D) according to preoperative myopia. Each patient was followed up for over 6 months with measurements of uncorrected visual acuity and manifest refraction at 1 week and 1, 3, and 6 months after operation. Complications during and after the operation were reviewed retrospectively in two groups 6month after the operation. Results: In groups F-I, F-II, M-I, and M-II, postoperative 6-month uncorrected visual acuity was 0.98±0.08, 0.96±0.09, 0.97±0.03, 0.98±0.09. At the 6-month follow-up, there were no significant differences between the two groups in uncorrected visual acuity and mean spherical equivalent. Corneal opacity was found in 3 eyes in group M and complication related with flap was found 1 eye in group F and 4 eyes in group M. Conclusions: During a 6-month follow up, LASIK using either a femtosecond laser or a microkeratome has an similar effect in uncorrected visual acuity and mean spherical equivalent. Thus LASIK for using femtosecond laser can be used as an alternative procedure to correct myopia.

Fully subthreshold current-based characterization of interface traps and surface potential in III-V-on-insulator MOSFETs

Kim, S.K.,Lee, J.,Geum, D.M.,Park, M.S.,Choi, W.J.,Choi, S.J.,Kim, D.H.,Kim, S.,Kim, D.M. Pergamon Press ; Elsevier Science Ltd 2016 Solid-state electronics Vol.122 No.-

We report characterization of the interface trap distribution (D<SUB>it</SUB>(E)) over the bandgap in III-V metal-oxide-semiconductor field-effect transistors (MOSFETs) on insulator. Based only on the experimental subthreshold current data and differential coupling factor, we simultaneously obtained D<SUB>it</SUB>(E) and a nonlinear mapping of the gate bias (V<SUB>GS</SUB>) to the trap level (E<SUB>t</SUB>) via the effective surface potential (ψ<SUB>S,eff</SUB>). The proposed technique allows direct extraction of the interface traps at the In<SUB>0.53</SUB>Ga<SUB>0.47</SUB>As-on insulator (-OI) MOSFETs only from the experimental subthreshold current data. Applying the technique to the In<SUB>0.53</SUB>Ga<SUB>0.47</SUB>As channel III-V-OI MOSFETs with the gate width/length W/L=100/50, 100/25, and 100/10μm/μm, we obtained D<SUB>it</SUB>(E)@?10<SUP>11</SUP>-10<SUP>12</SUP>eV<SUP>-1</SUP>cm<SUP>-2</SUP> over the bandgap without the dimension dependence.