• 제목/요약/키워드: $V_S$-profile

검색결과 243건 처리시간 0.031초

Increased Activity of Large Conductance $Ca^{2+}-Activated$ $K^+$ Channels in Negatively-Charged Lipid Membranes

  • Park, Jin-Bong;Ryu, Pan-Dong
    • The Korean Journal of Physiology and Pharmacology
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    • 제2권4호
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    • pp.529-539
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    • 1998
  • The effects of membrane surface charge originated from lipid head groups on ion channels were tested by analyzing the activity of single large conductance $Ca^{2+}-activated\;K^+$ (maxi K) channel from rat skeletal muscle. The conductances and open-state probability ($P_o$) of single maxi K channels were compared in three types of planar lipid bilayers formed from a neutral phosphatidylethanolamine (PE) or two negatively-charged phospholipids, phosphatidylserine (PS) and phosphatidylinositol (PI). Under symmetrical KCl concentrations $(3{\sim}1,000\;mM)$, single channel conductances of maxi K channels in charged membranes were $1.1{\sim}1.7$ times larger than those in PE membranes, and the differences were more pronounced at the lower ionic strength. The average slope conductances at 100 mM KCl were $251{\pm}9.9$, $360{\pm}8.7$ and $356{\pm}12.4$ $(mean{\pm}SEM)$ pS in PE, PS and PI membranes respectively. The potentials at which $P_o$ was 1/2, appeared to have shifted left by 40 mV along voltage axis in the membranes formed with PS or PI. Such shift was consistently seen at pCa 5, 4.5, 4 and 3.5. Estimation of the effect of surface charge from these data indicated that maxi K channels sensed the surface potentials at a distance of $8{\sim}9\;{\AA}$ from the membrane surface. In addition, similar insulation distance ($7{\sim}9\;{\AA}$) of channel mouth from the bilayer surface charge was predicted by a 3-barrier-2-site model of energy profile for the permeation of $K^+$ ions. In conclusion, despite the differences in structure and fluidity of phospholipids in bilayers, the activities of maxi K channels in two charged membranes composed of PS or PI were strikingly similar and larger than those in bilayers of PE. These results suggest that the enhancement of conductance and $P_o$ of maxi channels is mostly due to negative charges in the phospholipid head groups.

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헬륨 대기압 유전체 격벽 방전기의 타운젠트-글로우 방전 모드 전이 연구 (Observation of Discharge Mode Transient from Townsend to Glow at Breakdown of Helium Atmospheric Pressure Dielectric Barrier Discharge)

  • 배병준;김남균;윤성영;신준섭;김곤호
    • 반도체디스플레이기술학회지
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    • 제15권2호
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    • pp.26-31
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    • 2016
  • The Townsend to glow discharge mode transition was investigated in the dielectric barrier discharge (DBD) helium plasma source which was powered by 20 kHz / $4.5 kV_{rms}$ high voltage at atmospheric pressure. The spatial profile of the electric field strength at each modes was measured by using the intensity ratio method of two helium emission lines (667.8 nm ($3^1D{\rightarrow}2^1P$) and 728.1 nm ($3^1S{\rightarrow}2^1P$)) and the Stark effect. ICCD images were analyzed with consideration for the electric field property. The Townsend discharge (TD) mode at the initial stage of breakdown has the light emission region located in the vicinity of the anode. The electric field of the light emitting region is close to the applied field in the system. Immediately, the light emitting region moves to the cathode and the discharge transits to the glow discharge (GD) mode. This mode transition can be understood with the ionization wave propagation. The electric field of the emitting region of GD near cathode is higher than that of TD near anode because of the cathode fall formation. This observation may apply to designing a DBD process system and to analysis of the process treatment results.

Population diversity, admixture, and demographic trend of the Sumba Ongole cattle based on genomic data

  • Pita Sudrajad;Hartati Hartati;Bayu Dewantoro Putro Soewandi;Saiful Anwar;Angga Ardhati Rani Hapsari;Tri Satya Mastuti Widi;Sigit Bintara;Dyah Maharani
    • Animal Bioscience
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    • 제37권4호
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    • pp.591-599
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    • 2024
  • Objective: Sumba Ongole (SO) cattle are valuable breed due to their important role in the development of Indonesian cattle. Despite rapid advances in molecular technology, no genomic studies on SO cattle have been conducted to date. The aim of this study is to provide genomic profile related to the population diversity, admixture, and demographic trends of SO cattle. Methods: Genomic information was gathered from 79 SO cattle using the Illumina Bovine SNP50 v3 Beadchip, and for comparative purposes, additional genotypes from 209 cattle populations worldwide were included. The expected and observed heterozygosity, inbreeding coefficient, pairwise fixation indices between-population, and Nei's genetic distance were examined. Multidimensional scaling, admixture, and treemix analyses were used to investigate the population structure. Based on linkage disequilibrium and effective population size calculations, the demographic trend was observed. Results: The findings indicated that the genetic diversity of SO cattle was similar to that of other indicine breeds. SO cattle were genetically related to indicines but not to taurines or Bali cattle. The study further confirmed the close relationship between SO, Ongole, and Nellore cattle. Additionally, a small portion of the Ongole mixture were identified dominant in the SO population at the moment. The study also discovered that SO and Bali cattle (Bos javanicus) could have been ancestors in the development of Ongole Grade cattle, which corresponds to the documented history of Ongolization. Our finding indicate that SO cattle have maintained stability and possess unique traits separate from their ancestors. Conclusion: In conclusion, the genetic diversity of the SO cattle has been conserved as a result of the growing significance of the present demographic trend. Consistent endeavors are necessary to uphold the fitness of the breed.

Dynamic Contrast Enhanced MRI and Intravoxel Incoherent Motion to Identify Molecular Subtypes of Breast Cancer with Different Vascular Normalization Gene Expression

  • Wan-Chen Tsai;Kai-Ming Chang;Kuo-Jang Kao
    • Korean Journal of Radiology
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    • 제22권7호
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    • pp.1021-1033
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    • 2021
  • Objective: To assess the expression of vascular normalization genes in different molecular subtypes of breast cancer and to determine whether molecular subtypes with a higher vascular normalization gene expression can be identified using dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) and intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI). Materials and Methods: This prospective study evaluated 306 female (mean age ± standard deviation, 50 ± 10 years), recruited between January 2014 and August 2017, who had de novo breast cancer larger than 1 cm in diameter (308 tumors). DCE MRI followed by IVIM DWI studies using 11 different b-values (0 to 1200 s/mm2) were performed on a 1.5T MRI system. The Tofts model and segmented biexponential IVIM analysis were used. For each tumor, the molecular subtype (according to six [I-VI] subtypes and PAM50 subtypes), expression profile of genes for vascular normalization, pericytes, and normal vascular signatures were determined using freshly frozen tissue. Statistical associations between imaging parameters and molecular subtypes were examined using logistic regression or linear regression with a significance level of p = 0.05. Results: Breast cancer subtypes III and VI and PAM50 subtypes luminal A and normal-like exhibited a higher expression of genes for vascular normalization, pericyte markers, and normal vessel function signature (p < 0.001 for all) compared to other subtypes. Subtypes III and VI and PAM50 subtypes luminal A and normal-like, versus the remaining subtypes, showed significant associations with Ktrans, kep, vp, and IAUGCBN90 on DEC MRI, with relatively smaller values in the former. The subtype grouping was significantly associated with D, with relatively less restricted diffusion in subtypes III and VI and PAM50 subtypes luminal A and normal-like. Conclusion: DCE MRI and IVIM parameters may identify molecular subtypes of breast cancers with a different vascular normalization gene expression.

대한해협 횡단면 상의 수온-염분과 해류의 구조 및 변동 (Structures and Variability of the T-S field and the Current across the Korea Strait)

  • 노영재;박문진;이상룡;이재철
    • 한국해양학회지
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    • 제30권4호
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    • pp.237-249
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    • 1995
  • 대한 해협 횡단면 상의 수온, 염분 및 해류의 구조를 이해하기 위하여 1994년 5월 2일부터 20일 까지 현장 조사를 수행하였다. 연구선 탐양호를 이용하여 상세한 CTD 수 직 profile과 ADCP 측정 기록을 얻었으며 두 개의 시간차(15일과 25시간)에 대한 평균 장과 변동장을 분석하였다. 대한 해협 중앙부에는 서로 다른 두 개의 수기 즉 동측의 고온 고염수와 서측의 저온저염수가 서로 인접하면서 대단히 뚜렷한 연안 전선을 형성 하고 있다. 이 고운 고염 수괴가 약 보름에 걸쳐서 서진하면서 수온 염분장을 크게 변 화 시키고 있음을 관찰할 수 있었다. 또한 중층에서는 수시간대의 짧은 주기로서도 수 온과 염분이 변화하고 있었으며, 이 현상은 EOF분석에서 제 1고유 모드로 나타나며 그 것은 50%이상의 전체 분산을 점하고 있다. 대한 해협에서의 흐름은 조류에 의하면 심 하게 영향을 받고 있으며 해협 중앙부에서 사리와 조금 때 각각 최대 80-90 및 60-70 cm/s의 크기를 보여 준다. 강한 남향의 조류에 의해 때에 따라서는 북향하는 대마 난 류의 존재가 완전히 가려 보이지 않기도 하였다. 25시간 연속 해류 관측 결과의 조화 분석 결과사리와 조금 때 평균, 단일주조류 및 일일주조류의 크기가 서로 비슷함을 알 수 있었다. 대한 해협 서수도를 통과하는 용접수송량은 조금 때 2.1 사리 때에 3.4 Sv 으로 추정되었다.

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Utilization of Graded Levels of Finger Millet (Eleusine coracana) in Place of Yellow Maize in Commercial Broiler Chicken Diets

  • Rama Rao, S.V.;Raju, M.V.L.N.;Reddy, M.R.;Panda, A.K.
    • Asian-Australasian Journal of Animal Sciences
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    • 제18권1호
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    • pp.80-84
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    • 2005
  • An experiment was conducted to study the performance, carcass traits, serum lipid profile and immune competence in commercial broilers (2 to 42 d of age) fed graded levels (25, 50, 75 and 100%) of finger millet (FM) (Elusine coracana) in place (w/w) of yellow maize (YM). Each diet was fed to eight replicates (five female Vencobb broilers/replicate) housed in stainless steel battery brooders. The estimated metabolizable energy content of FM was about 540 kcal less than the YM. FM contained more protein (10.42 vs. 9.05%) and fibre (9.52 vs. 2.24%) compared to YM. Body weight gain, ready to cook yield, relative weights of giblet, liver, intestine and length of intestine at 42 d of age was not affected due to replacing YM with FM. But, the feed efficiency decreased in broilers fed diets containing 75 and 100% FM in place of YM at both 21 and 42 d of age. The amount of fat deposited in abdominal area decreased and the relative weight of gizzard increased with increase in level of FM in the diet. The serum HDL cholesterol at 21 and 42 d of age and serum triglycerides at 42 d of age decreased with increase in level of FM in diet. The relative weight of spleen and antibody titers against sheep red blood cells (SRBC) at 5 d post inoculation (PI) decreased in broilers fed FM at 100% of YM. However, the relative weight of bursa, SRBC titers at 10 d PI, antibody titers against ND virus and mortality were not affected due to incorporation of FM in place of YM in diet. The fat content in thigh muscle and liver decreased, while the protein content in these tissues increased with increase in the level of FM in broiler diet. Based on the results, it may be concluded that YM can be replaced with FM up to 25% on weight basis without affecting weight gain, carcass yields and immunity in commercial broiler diet (up to 42 d of age). Further, inclusion of finger millet reduced the fat deposition in thigh muscle, liver and in abdominal area compared to those fed maize as the principal source of energy.

교통사고 환자의 MMPI 및 통증, 영상평가에 대한 임상연구 (Clinical Study on Pain Index, Radiological Evaluation and MMPI of Traffic Accident Patient)

  • 김성태;송민영;김대훈;이은지;권민구;설재욱;김선종;배길준;최진봉
    • 한방재활의학과학회지
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    • 제25권1호
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    • pp.77-85
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    • 2015
  • This study analyzed the MMPI (Minnesota Multiphashic Personality Inventory), VAS (Visual Analogue Scale), cervical and lumbar curvature (Cervical angle, Ishihara Index, Lumbar angle, Ferguson angle) and satisfaction score of patient of traffic accident. About 59 cases of patients admitted to the Korean Medicine hospital, MMPI and pain levels (VAS) cervical and lumbar curvature (Cervical angle, Ishihara Index, lumbar angle, Ferguson angle) and satisfaction score were measured and statistically analyzed. Depending on the type of accident divided into two groups of In car TA and Out car TA. After hospitalization, patient's pain index was improved as a whole. Pain index and evaluation of the cervical and lumbar curvature, according to the accident types, the difference was not statistically significant. In the analysis of the MMPI validity scales, In car TA group was analyzed by 'V-shaped', Out car TA group was analyzed by umbrella- shaped, 'inverted V-shaped'. Clinical scales of out car TA group were analyzed by 3-1 profile compared to the In car TA group. Results of multiple regression analysis showed no association between factors and MMPI scales. In the case of a traffic accident patients, damage to the body, as well as emotional and psychological factors are thought to affect the condition or prognosis of patients. In the future, for the management and treatment of these parts will be needed to complement the academic or institutional.

휘어진 경계에서의 좁은 영역에 대한 Radiochromic 필름 도시메트리 평가 (Evaluation of the Radiochromic Film Dosimetry for a Small Curved Interface)

  • 강세권;박소아;황태진;정광호;한태진;김해영;이미연;김경주;배훈식
    • 한국의학물리학회지:의학물리
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    • 제23권4호
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    • pp.234-238
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    • 2012
  • 눈꺼풀에 발생한 종양의 치료를 위해서는 종종 고에너지 전자선이 이용되며, 이 경우 환자의 시력 보호를 위해 금속차폐체를 눈꺼풀과 안구 사이에 삽입하고 방사선 치료를 시행한다. 차폐체에 접한 눈꺼풀 안쪽의 방사선량 확인을 위해서는 매우 작은 측정도구가 필요하며, 굽은 경계면의 특성상 유연한 측정도구가 바람직한데, radiochromic 필름 도시메트리는 이 목적에 매우 적합하다. 작으면서도 휘어진 경계면을 따라서 선량을 측정하기 위해, 눈꺼풀 팬텀과 차폐체 사이에 3-mm 폭의 EBT2 필름 띠를 삽입하고, 6MeV의 전자선을 조사 후, 선량분포를 얻었다. 금속차폐체와 동일한 크기로 아크릴 재질의 차폐체를 제작하여, 금속인공영상물이 없는 CT 영상을 얻은 후, 이를 이용하여 몬테칼로 전산모사를 수행하였다. 전산모사에서는 실제 안구차폐체의 재질을 따라 텅스텐, 알루미늄 및 스테인레스 스틸 등의 물질 정보를 이용하였다. 이렇게 얻은 전산모사 결과는 필름 측정과 2.1% 내에서 일치하였다. 밀리미터 크기 정도로 작고 또한 휘어진 영역에서 radiochromic 필름 도시메트리는 취급도 용이할 뿐만 아니라 만족스런 정확도를 보여주고 있다.

A Review and Analysis of the Thermal Exposure in Large Compartment Fire Experiments

  • Gupta, Vinny;Hidalgo, Juan P.;Lange, David;Cowlard, Adam;Abecassis-Empis, Cecilia;Torero, Jose L.
    • 국제초고층학회논문집
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    • 제10권4호
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    • pp.345-364
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    • 2021
  • Developments in the understanding of fire behaviour for large open-plan spaces typical of tall buildings have been greatly outpaced by the rate at which these buildings are being constructed and their characteristics changed. Numerous high-profile fire-induced failures have highlighted the inadequacy of existing tools and standards for fire engineering when applied to highly-optimised modern tall buildings. With the continued increase in height and complexity of tall buildings, the risk to the occupants from fire-induced structural collapse increases, thus understanding the performance of complex structural systems under fire exposure is imperative. Therefore, an accurate representation of the design fire for open-plan compartments is required for the purposes of design. This will allow for knowledge-driven, quantifiable factors of safety to be used in the design of highly optimised modern tall buildings. In this paper, we review the state-of-the-art experimental research on large open-plan compartment fires from the past three decades. We have assimilated results collected from 37 large-scale compartment fire experiments of the open-plan type conducted from 1993 to 2019, covering a range of compartment and fuel characteristics. Spatial and temporal distributions of the heat fluxes imposed on compartment ceilings are estimated from the data. The complexity of the compartment fire dynamics is highlighted by the large differences in the data collected, which currently complicates the development of engineering tools based on physical models. Despite the large variability, this analysis shows that the orders of magnitude of the thermal exposure are defined by the ratio of flame spread and burnout front velocities (VS / VBO), which enables the grouping of open-plan compartment fires into three distinct modes of fire spread. Each mode is found to exhibit a characteristic order of magnitude and temporal distribution of thermal exposure. The results show that the magnitude of the thermal exposure for each mode are not consistent with existing performance-based design models, nevertheless, our analysis offers a new pathway for defining thermal exposure from realistic fire scenarios in large open-plan compartments.

전달함수합성법에 의한 차체-엔진계의 실험적 진동해석 (Experimental Vibration Analysis of Vehicle Body-Engine Systems by Transfer Function Synthesis Method)

  • 정의봉;안세진;김원영
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 1995년도 추계학술대회논문집; 한국종합전시장, 24 Nov. 1995
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    • pp.289-295
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    • 1995
  • 구조물의 동적부하에 대한 동적변형 응답을 정확히 예측하고, Over Design이나 Under Design이 아닌 합리적인 설계방안의 개발은 중요한 과제이다. 동적강도해석이나 소음 승차감과 같은 진동 및 충격에 기인하는 제반 문제를 복잡한 구조물을 대상으로 합리적으로 처리하기 위한 Dynamic Design Analysis는 높은 신뢰성의 추구와 더불어 필요불가결한 기술이 되고 있다. 동적해석 방법으로는 현재 유한요소법이 널리 사용되고 있으며 여러 종류의 범용 프로그램들이 보급되어 있는 실정이다. 그러나 특히 동적문제에 있어서는 형상이나 거동이 복잡한 구조물의 경우, 또는 차량의 차체와 같이 많은 장착물이 부착된 경우에는 유한요소법의 적용이 곤란하여, 지금까지 대처할 수 있는 유용한 방법이 없었다. 따라서 비교적 용이하고 간단하게 적용가능한 진동실험을 기초로 한 구조물의 동적 응답해석 및 설계 방안의 개발이 필요하다. 본 연구에서는 진동시험으로 얻어진 부분구조물의 응답특성과 결합특성으로부터 결합 후의 응답특성을 예측할 수 있는 방법을 전달함수합성이론을 기초로하여 프로그래밍 package화 한다. 그리고 평판구조물에 대하여 진동시험과 컴퓨터 시뮬레이션을 통하여 개발된 방법의 타당성을 검증한다. 또한 실제 차량에서 차체만의 진동시험과 엔진의 자유진동시험에 의한 시험데이터로부터 차체와 엔진이 마운트 결합된 후의 진동특성을 예측한다. 진동시험시에 입력과 출력에 노이즈가 필연적으로 혼입되어 주파수응답함수의 크기(magnitude)와 위상(phase)을 왜곡시킨다. 특히 위상의 왜곡은 복소수연산을 하는 전달함수합성법의 결과에 중요한 영향을 미치게 된다. 본 연구에서는 데이타 획득시 입력과 출력의 시간지연으로 생기는 위상왜곡을 보정하는 방법을 제시하고, 그 개선 정도를 조사한다.는 소견의 확실도로서 가능성을 표현한 것이다. 예를 들면, 진동진폭 스펙트럼상에 2X 성분이 상당히 크게 나타나 정렬불량의 가능성이 0.7 정도라고 판정하는 것 등은 이러한 수치적진리치를 이용하는 방법이다. 그러나 상기의 수치적 표현만으로는 확실도를 한개의 수치로서 대표하게 하는 것은 진단의 정밀도에 문제가 있을 것으로 생각된다. 따라서 언어적진리치가 도입되어 [상당히 확실], [확실], [약간 확실] 등의 언어적인 표현을 이용하여 애매성을 표현하게 되었다. 본 논문에서는 간이진단 결과로부터 추출된 애매한 진단결과중에서 가장 가능성이 높은 이상원인을 복수로 선정하고, 여러 종류의 수치화할 수 없는 언어적(linguistic)인 정보ㄷㄹ을 if-then 형식의 퍼지추론으로 종합하는 회전기계의 이상진단을 위한 정밀진단 알고리즘을 제안하고 그 유용성을 검토한다. 존재하여도 모우드 변수들을 항상 정확하게 구할 수 있으며, 또한 알고리즘의 안정성이 보장된 것이다.. 여기서는 실험실 수준의 평 판모델을 제작하고 실제 현장에서 이루어질 수 있는 진동제어 구조물에 대 한 동적실험 및 FRS를 수행하는 과정과 동일하게 따름으로써 실제 발생할 수 있는 오차나 error를 실험실내의 차원에서 파악하여 진동원을 있는 구조 물에 대한 진동제어기술을 보유하고자 한다. 이용한 해마의 부피측정은 해마경화증 환자의 진단에 있어 육안적인 MR 진단이 어려운 제한된 경우에만 실제적 도움을 줄 수 있는 보조적인 방법으로 생각된다.ofile whereas relaxivity at high field is not affected by τS. On the other hand, the change in τV does not affect low field profile but strongly in fluences on bot

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