• 제목/요약/키워드: macroscopic

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In Vivo Non Invasive Molecular Imaging for Immune Cell Tracking in Small Animals

  • Youn, Hyewon;Hong, Kee-Jong
    • IMMUNE NETWORK
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    • 제12권6호
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    • pp.223-229
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    • 2012
  • Clinical and preclinical in vivo immune cell imaging approaches have been used to study immune cell proliferation, apoptosis and interaction at the microscopic (intra-vital imaging) and macroscopic (whole-body imaging) level by use of ex vivo or in vivo labeling method. A series of imaging techniques ranging from non-radiation based techniques such as optical imaging, MRI, and ultrasound to radiation based CT/nuclear imaging can be used for in vivo immune cell tracking. These imaging modalities highlight the intrinsic behavior of different immune cell populations in physiological context. Fluorescent, radioactive or paramagnetic probes can be used in direct labeling protocols to monitor the specific cell population. Reporter genes can also be used for genetic, indirect labeling protocols to track the fate of a given cell subpopulation in vivo. In this review, we summarized several methods dealing with dendritic cell, macrophage, and T lymphocyte specifically labeled for different macroscopic whole-body imaging techniques both for the study of their physiological function and in the context of immunotherapy to exploit imaging-derived information and immune-based treatments.

수학교육 연구영역의 확장과 통찰력 연구 (The Extension of Research Area in Mathematics Education and Getting Insight)

  • 문권배
    • 한국수학교육학회지시리즈E:수학교육논문집
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    • 제28권3호
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    • pp.423-429
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    • 2014
  • 초행길 인생인 우리들이 시행착오를 줄이려면, 인류가 이룩한 인생살이의 교훈과 노하우를 미리미리 교육을 통해 깨닫는 것이 필요하다. 교육현장에서 미시적 탐구 위주의 수학교육 연구영역을 삶에 관계되는 영역까지 확장하여, 인생살이를 효율적으로 통찰하고자 한다. 본 연구는 인생살이를 살피는 방법들을 크게 네 가지로 분류하고, 인생살이 통찰에 필요한 수학적 모델을 경험 가능한 일상영역에서 찾을 수 있도록 설계하였다. 이렇게 만들어진 모델세계로 인생살이를 통찰하는 예를 통해, 수학적 모델링으로 인생살이를 통찰하는 방법을 새롭게 소개한다.

역확산을 고려한 이원합금의 비평형 수지상응고 해석 (Analysis on the non-equilibrium dendritic solidification of a binary alloy with back diffusion)

  • 정재동;유호선;이준식
    • 대한기계학회논문집B
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    • 제20권10호
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    • pp.3361-3370
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    • 1996
  • Micro-Macro approach is conducted for the mixture solidification to handle the closely linked phenomena of microscopic solute redistribution and macroscopic solidification behavior. For this purpose, present work combines the efficiency of mixture theory for macro part and the capability of microscopic analysis of two-phase model for micro part. The micro part of present study is verified by comparison with experiment of Al-4.9 mass% Cu alloy. The effect of back diffusion on the macroscopic variables such as temperature and liquid concentration, is appreciable. The effect, however, is considerable on the mixture concentration and eutectic fraction which are indices of macro and micro segregation, respectively. According to the diffusion time, the behavior near the cooling wall where relatively rapid solidification permits short solutal diffusion time, approaches Scheil equation limit and inner part approaches lever rule limit.

가솔린 인젝터의 연료 분무 미립화 특성에 미치는 분사 압력의 영향 (Effect of Injection Pressure on Atomization Characteristics of Fuel Spray in High-Pressure Gasoline Injector)

  • 이창식;최수천;김민규;권상일
    • 대한기계학회논문집B
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    • 제24권4호
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    • pp.555-560
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    • 2000
  • This paper describes the macroscopic behavior and atomization characteristics of the high-pressure gasoline injector in direct-injection gasoline engine. The global spray behavior of fuel injector was visualized by shadowgraph technique. The atomization characteristics of gasoline spray such as mean diameter and mean velocity of droplet were measured by the phase Doppler particle analyzer system. In order to obtain the influence of fuel injection pressure, the macroscopic visualization and experiment of particle measurement on the fuel spray were investigated at 3,5 and 7 MPa of injection pressure under different surrounding pressure in the spray chamber. The results of this work show that the fuel injection pressure of gasoline injector in GDl engine has influence upon the mean droplet diameter, mean velocity of spray droplet, the spray tip penetration, and spray width under the elevated ambient pressure.

개의 태아사 및 태아침지 (Fetal Death and Maceration in dog)

  • 신창록;손창호;박인철;최한선;강병규
    • 한국임상수의학회지
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    • 제14권1호
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    • pp.112-117
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    • 1997
  • 12-month-old Buldig and 3-year-old German Shepherd, treated with corticosteroids duringthe late pregnancy, were referred to the Veterinary Teaching Hospital, Chonnam National University, with chief complaints of vaginal discharge. Radiographic, ultrasonographic and surgical findings that obtained from each cases were as follows; case I: Radiographic findings were identified 2 fetuses that were normal skeleton, however, fetal viability could not be determined. Ultrasonographic findings were identified absence of fetal heartbeat and fetal movement, abnormal echogenicity of the abdominal visera, and echogenic materials remaining within the fetal fluid. After hysterotomy, macroscopic findings of uterus were liquefied materials remaining within the uterine lumen. Fetuses were excessively autolysis (falling off the hair, depression of the eye, and necrosis of the abdormal visera and skin). case II: Radiographic findings were identified irregular fetal structures and fetal movement, loss of recognizable fetal anatomy, dislocation of fetal veterbrae and echogenic materials remaining within the uterine lumen. After ovariohysterectomy, macroscopic finding of uterus and fetus were thickened uterine wall, yellowish-brown colored administration of corticosteroids during gestation should be contraindicated because fetal death is inducced. Ultrasonography has an advantage over radiography in that it permits evaluation of fetal viability.

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Evolution of sandstone shear strength parameters and its mesoscopic mechanism

  • Shi, Hao;Zhang, Houquan;Song, Lei
    • Geomechanics and Engineering
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    • 제20권1호
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    • pp.29-41
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    • 2020
  • It is extremely important to obtain rock strength parameters for geological engineering. In this paper, the evolution of sandstone cohesion and internal friction angle with plastic shear strain was obtained by simulating the cyclic loading and unloading tests under different confining pressures using Particle Flow Code software. By which and combined with the micro-crack propagation process, the mesoscopic mechanism of parameter evolution was studied. The results show that with the increase of plastic shear strain, the sandstone cohesion decreases first and then tends to be stable, while the internal friction angle increases first, then decreases, and finally maintains unchanged. The evolution of sandstone shear strength parameters is closely related to the whole process of crack formation, propagation and coalescence. When the internal micro-cracks are less and distributed randomly and dispersedly, and the rock shear strength parameters (cohesion, internal friction angle) are considered to have not been fully mobilized. As the directional development of the internal micro-fractures as well as the gradual formation of macroscopic shear plane, the rock cohesion reduces continuously and the internal friction angle is in the rise stage. As the formation of the macroscopic shear plane, both the rock cohesion and internal friction angle continuously decrease to a certain residual level.

Modeling time-dependent behavior of hard sandstone using the DEM method

  • Guo, Wen-Bin;Hu, Bo;Cheng, Jian-Long;Wang, Bei-Fang
    • Geomechanics and Engineering
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    • 제20권6호
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    • pp.517-525
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    • 2020
  • The long-term stability of rock engineering is significantly affected by the time-dependent deformation behavior of rock, which is an important mechanical property of rock for engineering design. Although the hard rocks show small creep deformation, it cannot be ignored under high-stress condition during deep excavation. The inner mechanism of creep is complicated, therefore, it is necessary to investigate the relationship between microscopic creep mechanism and the macro creep behavior of rock. Microscopic numerical modeling of sandstone creep was performed in the investigation. A numerical sandstone sample was generated and Parallel Bond contact and Burger's contact model were assigned to the contacts between particles in DEM simulation. Sensitivity analysis of the microscopic creep parameters was conducted to explore how microscopic parameters affect the macroscopic creep deformation. The results show that the microscopic creep parameters have linear correlations with the corresponding macroscopic creep parameters, whereas the friction coefficient shows power function with peak strength and Young's modulus, respectively. Moreover, the microscopic parameters were calibrated. The creep modeling curve is in good agreement with the verification test result. Finally, the creep curves under one-step loading and multi-step loading were compared. This investigation can act as a helpful reference for modeling rock creep behavior from a microscopic mechanism perspective.

Is it Necessary to Submit Grossly Normal Looking Gall Bladder Specimens for Histopathological Examination?

  • Tayeb, Muhammad;Rauf, Fozia;Ahmad, Khurshid;Khan, Faiz Muhammad
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권4호
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    • pp.1535-1538
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    • 2015
  • Background: The objectives of the study were to: 1) determine the frequency of incidental malignancy in unsuspected/grossly normal looking gall bladders; 2) determine the frequency of malignancy in suspected/grossly abnormal looking gall bladders. Materials and Methods: This prospective, cross sectional study was carried out at a tertiary care hospital in Pakistan, during a four year period (Jan 2009-dec2012). All the cholecystectomy cases performed for gallstone diseases were examined initially by a surgeon and later on by a pathologist for macroscopic abnormalities and accordingly assigned to one of the three categories i.e. grossly normal, suspicious, abnormal/malignant. Frequency of incidental carcinoma in these categories was observed after receiving the final histopathology report. Results: A total of 426 patients underwent cholecystectomy for cholelithiasis, with a 1:4 male: female ratio. Mean age of the patients was 45 years with a range of 17-80 years. The frequency of incidental gallbladder carcinoma was found to be 0.70 %(n=3). All the cases of gallbladder carcinoma were associated with some macroscopic abnormality. Not a single case of incidental carcinoma gallbladder was diagnosed in 383 'macroscopically normal looking' gallbladders. Conclusions: Incidental finding of gall bladder cancer was not observed in any of macroscopically normal looking gall bladders and all the cases reported as carcinoma gallbladder had some gross abnormality that made them suspicious. We suggest histopathologic examination of only those gall bladders with some gross abnormality.

고압 스월분무 내부의 압력분포 및 유동특성에 대한 연구 (The Static Pressure Distribution and Flow Characteristics Inside the High-Pressure Swirl Spray)

  • 문석수;;최재준;배충식
    • 한국분무공학회지
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    • 제11권3호
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    • pp.168-175
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    • 2006
  • The static pressure distribution and flow characteristics inside the high-pressure swirl spray were investigated by measuring the static pressure inside the spray and applying the computational fluid dynamics (CFD). The static pressure difference between inner and outer part of spray was measured at different axial locations and operating conditions using a piezo-resislive pressure transducer. To obtain the qualitative value of swirl motion at different operating conditions, the spray impact-pressure at the nozzle exit was measured using a piezo-electric pressure transducer, and the flow angle was measured using a microscopic imaging system. The flow characteristics inside the high pressure swirl spray was simulated by the 1-phase 3-dimensional CFD model. The effect of pressure alternations on spray development was discussed with macroscopic spray images and a mathematical liquid film model. The results showed that the static pressure drop is observed inside the swirl spray as a result of the dragged air motion and the centrifugal force of the air. The recirculation vortex inside the spray was also observed inside the swirl spray as a result of the adverse pressure gradient along the axial locations. The results of analytical liquid film model and macroscopic spray images showed that the static pressure structure is one of the main parameters affecting the swirl spray development.

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Skin Wound Healing Effects and Action Mechanism of Acai Berry Water Extracts

  • Kang, Mi Hyun;Choi, Seunghye;Kim, Bae-Hwan
    • Toxicological Research
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    • 제33권2호
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    • pp.149-156
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    • 2017
  • The purpose of this study was to investigate the wound healing effect of acai berry water extracts (ABWE) and a possible underlying mechanism involved in its action using various in vitro and in vivo models. The wound healing effect of ABWE was evaluated by migration assay using HS68 fibroblast cells. In addition, its effect on mRNA expression of procollagen, fibronectin, and MMP-1 was determined. Moreover, the wound healing effect of ABWE was evaluated in in vivo wound models through macroscopic and microscopic observation. In addition, mRNA expression levels of wound related genes were determined. Results revealed that ABWE was not cytotoxic. It increased migration of HS68 fibroblast cells. ABWE increased mRNA expression levels of fibronectin but decreased the mRNA expression levels of MMP-1. ABWE also showed significantly potent wound healing effect in vivo based on macroscopic and histopathological observation and mRNA expression evaluation for wound related genes. Taken together, our results indicated that ABWE might have potential as a wound healing agent.