• Molecules and Cells
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• v.40 no.12
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• pp.889-896
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• 2017

Nuclear bodies are subnuclear, spheroidal, and membraneless compartments that concentrate specific proteins and/or RNAs. They serve as sites of biogenesis, storage, and sequestration of specific RNAs, proteins, or ribonucleoprotein complexes. Recent studies reveal that a subset of nuclear bodies in various eukaryotic organisms is constructed using architectural long noncoding RNAs (arcRNAs). Here, we describe the unifying mechanistic principles of the construction and function of these bodies, especially focusing on liquid-liquid phase separation induced by architectural molecules that form multiple weakly adhesive interactions. We also discuss three possible advantages of using arcRNAs rather than architectural proteins to build the bodies: position-specificity, rapidity, and economy in sequestering nucleic acid-binding proteins. Moreover, we introduce two recently devised methods to discover novel arcRNA-constructed bodies; one that focuses on the RNase-sensitivity of these bodies, and another that focuses on "semi-extractability" of arcRNAs.

• Applied Microscopy
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• v.11 no.1
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• pp.51-57
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• 1981

The process of the formation of polyhedra occlusion bodies and occlusion of viral nucleocapsids of Autographa californica Nuclear Polyhedrosis Virus in Spodoptera frugiperda cell were photomicrographed and described. Progeny viral nucleocapsids were observed in the nuclei of the host cells, bundled and then enveloped. The nucleoapsids were mainly accumulated near the membrane-like profiles. The nuclear membrane were hypertophied up to the cytoplasmic membrane. Prepolyhedral bodies were observed and they were growing with the accumulations of thread-like materials(polypeptides) produced by viral genes. The bundled and enveloped nucleocapsids were occluded into the growing polyhedra.

• 대한핵의학회:학술대회논문집
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• 2003.11a
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• pp.24.1-24.1
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• 2003

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.346-351
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• 2005

The outlet feeder pipe thinning in a PHWR (Pressurized Heavy Water Reactor) is caused by high pressure steam flow inside the pipe, which is a well known degradation mechanism called FAC (Flow Assisted Corrosion). In order to monitor the degradation, the thickness of the outlet bends closed to the exit of the pressure tube should be measured and analyzed at every official overhaul. This paper develops a mobile feeder pipe inspection robot that can minimize the irradiation dose of human workers by automating the measurement process. The robot can move by itself on the feeder pipe by using an inch worm mechanism, which is constructed by two gripper bodies that can fix the robot body on the pipe, one extendable and contractable actuator, and a rotation actuator connected the two gripper bodies to move forward and backward, and to rotate in the circumferential direction

• International Journal of Control, Automation, and Systems
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• v.4 no.1
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• pp.87-95
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• 2006

The outlet feeder pipe thinning in a PHWR (Pressurized Heavy Water Reactor) is caused by a high pressure steam flow inside the pipe, which is a well known degradation mechanism called a FAC (Flow Assisted Corrosion). In order to monitor the degradation, the thickness of the outlet bends close to the exit of the pressure tube should be measured and analyzed at every official overhaul. This paper describes a mobile feeder pipe inspection robot that can minimize the irradiation dose to human workers by automating the measurement process. The robot can move by itself on the feeder pipe by using an inch worm mechanism, which is constructed by two gripper bodies that can fix the robot body on to the pipe, one extendable and contractible actuator, and a rotation actuator connected to the two gripper bodies to move forward and backward, and to rotate in a circumferential direction.

• Applied Microscopy
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• v.5 no.1
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• pp.21-30
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• 1975

To investigate ultrastructural characteristics of cancer cell nucleus, 29 cases of malignant tumors of 9 different types were examined. The common findings were marked irregularity of nuclear membrane with pronounced infoldings, clumping of heterochromatin along inner nuclear membrane, enlargement and disturbance of configuration and composition of nucleolus, and frequent observations of nuclear bodies and nuclear inclusions. These findings confirm what have been observed by light microscopy, and are also the signes that can be observed in hyperactive cells. Thus, ultrastructural characteristics of cancerous nucleus are the great variability of nuclear size, shape and composition, but none of them appear to be specific.

• Structural Engineering and Mechanics
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• v.18 no.3
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• pp.343-362
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• 2004

Rocking response of rigid bodies with rectangular footprint, freely standing on horizontal rigid plane is studied analytically. Bodies are subjected to simulated single component of horizontal earthquakes. The effect of baseline correction, applied to simulated excitations, on the rocking response is first examined. The sensitiveness of rocking motion to the details of earthquakes and geometric properties of rigid bodies is investigated. Due to the demonstrated sensitivity of rocking response to these factors, prediction of rocking stability must be made in the framework of probability theory. Therefore, using a large number of simulated earthquakes, the effects of duration and shape of intensity function of simulated earthquakes on overturning probability of rigid bodies are studied. In the case when a rigid body is placed on any floor of a building, the corresponding probability is compared to that of a body placed on the ground. For this purpose, several shear frames are employed. Finally, the viability of the energy balance equation, which was introduced by Housner in 1963 and widely used by nuclear power industry to estimate the rocking stability of bodies, is evaluated. It is found that the equation is robust. Examples are also given to show how this equation can be used.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.5
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• pp.469-481
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• 2016

In this paper, a mathematical methodology was theoretically studied to obtain the impact force caused by the collision between rigid bodies. This theoretical methodology was applied to compute the impact force applied on the spent nuclear fuel disposal canister that accidentally drops and collides onto the ground. From this study, the impact force required to ensure a structurally safe canister design was theoretically formulated. The main content of the theoretical study concerns the rigid body kinematics and equation of motion during collision between two rigid bodies. On the basis of this study, a general impact theory to compute the impact force caused by the collision between two bodies was developed. This general impact theory was applied to theoretically formulate the approximate mathematical solution of the impact force that affects the spent nuclear fuel disposal canister that accidentally falls to the ground. Simultaneously, a numerical analysis was performed using the computer code to compute the numerical solution of the impact force, and the numerical result was compared with the approximate mathematical solution.

• 대한핵의학회:학술대회논문집
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• 2004.11a
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• pp.395.1-395.1
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• 2004

• The Korean Journal of Nuclear Medicine
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• v.37 no.1
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• pp.13-23
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• 2003

Neurodegenerative disorders cause a variety of dementia including Alzheimer disease, frontotemporal dementia, dementia with Lewy bodies, corticobasal degeneration, progressive supranuclear palsy, and Huntington's disease. PET scan is useful for early detection and differential diagnosis of these dementing disorders. Also, it provides valuable information about clinico-anatomical correlation, allowing better understanding of function of brain. Here we discuss recent achievements PET studies regarding these dementing disorders. Future progress in PET technology, new tracers, and image analysis will play an important role in further clarifying the disease pathophysiology and brain functions.