• YAKHAK HOEJI
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• v.48 no.3
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• pp.177-181
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• 2004

Non-invasive blood glucose measurement from mouse tail was performed by near-infrared (NIR) spectroscopy. Three groups; normal, type I diabetes (insulin dependent diabetes mellitus, IDDM), type II diabetes (non-insulin dependent diabetes mellitus, NIDDM) group, were studied over a 10 weeks period with the collection of near-infrared (NIR) spectra. Spectral variations from long-term measurement (10 weeks) from dramatic and nonlinear changes in the optical properties of the live tissue sample were compensated by chemometrics techniques such as principle component analysis (PCA) and partial least squares (PLS) regression. The effect from mouse body temperature changes on NIR spectral data was also considered. This study showed that the compensation of variations from long-term measurement and temperature changes improved calibration accuracy of non-invasive blood glucose measurement.

• Journal of Oral Medicine and Pain
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• v.49 no.2
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• pp.29-34
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• 2024

Acute malocclusion can occur in conditions related to temporomandibular joint (TMJ) disorders. This report presents two cases of acute malocclusion related to posterior disc displacement according to complete disc tearing. A 65-year-old male and an 88-yearold female presented with TMJ pain and occlusal discrepancies. Clinical examination, computed tomography, and magnetic resonance imaging revealed complete disc tearing and posterior displacement of a partial disc fragment. Dental cast analysis revealed a slight anterior and lateral deviation of the mandible toward the non-affected side; however, clinically, significant occlusal changes were not observed. This was attributed to the displacement of a small disc fragment rather than the entire disc. Including the cases presented, most instances of complete disc tearing responded well to conservative treatment such as pharmacotherapy and physical therapy, resulting in pain alleviation, and residual occlusal changes were tolerable for the patients in their daily activities. However, persistent occlusal changes or severe chewing difficulty may require surgical intervention.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.4
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• pp.349-355
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• 1990

Actomyosine prepared from Yellowtail fish(seriola quinqueradiata) were stored at $0^{\circ}C$(ice-cooling) -3.5$^{\circ}C$(partial freeaing) and -2$0^{\circ}C$(freezing) Another actomyosin samples were prepared from the fish previously stored at the temperatures for a week as the maximum .Remaining activity of {{{{ {Ca }^{2+ } }}}}-and {{{{ {Mg }^{2+ } }}}}- dependent adenosine triphosphatase(ATPase) activity was measured fronm the actomyosin preparations. Specific activity of {{{{ {Mg }^{2+ } }}}}-ATPase of actomy-osin before storagew was 0.253$\mu$ mole pi/min/mg of protein and it was 1.5 times higher than that of {{{{ {Ca }^{2+ } }}}} -ATPase. The enzyme activities were markedly decreased during early period of storage. However no significant differences in the enzyme activity were revealed among the samples stored at different temperature. The enzyme of actomyosin prepared from the fish previously stored at the temperatures for a week revealed an acitivity of 2-3 times higher than that of freezing. Apparent denaturation constant of {{{{ {Mg }^{2+ } }}}} -ATPase of actomyosin was between 0.810-1.139 per day and it was about 1.5 times hgiher than that of {{{{ {Ca }^{2+ } }}}} -ATPase. But the constant of {{{{ {Mg }^{2+ } }}}} ATPase of actomyosin extracted from the fist stored for a week at each temperature was between 0.176-0.356 per day. This constant was 4 times higher than that of {{{{ {Ca }^{2+ } }}}}- ATPase in frozen stored fish. It was presumed from these results that denaturation of ATPase is largely accorded to the structural changes of actomyosin.

• Applied Microscopy
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• v.27 no.2
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• pp.177-187
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• 1997

Hydrocephalus is induced experimentally in prenatal and suckling animals following an injection of 6-aminonicotinamide (6-AN). The most remarkable characteristic of these animals is aqueduct stenosis caused by swellings of the ependymal cells and subependymal cells in the periaqueductal gray matter and the central canal of the spinal cord. The present study was undertaken to investigate the morphological changes of the ependymal cells in the central canal of the spinal cord of 3.5 months old hamster after treatment with 6-AN. Intraperitoneal administrations of 6-AN (10 mg/kg body weight) every two days gave rise to partial central canal stenosis of the spinal cord after 27-29 days (13-l4th injection), but cilia and microvilli were located in the strictural area of the con#rat canal. The vacuolations in the ependymal cells were not observed and degenerating changes of intracellular organelles of the ependymal cells did not occur, so that the ependymal cells lining the central canal of the hamster spinal cord were not affected by 6-AN. But the present study demonstrate that 6-AN causes to create numerous vacuoles in the subependymal area of the central canal. Although the vacuoles were well developed in the neuroglial cells and the neuropils of the subependymal area, the neurons were not affected by 6-AN. These results strongly suggests that partial central canal stenosis occurred by 6-AN was due to vacuolations and swellings of the neuroglial cells and nueropils in the subependymal area.

• The Journal of Advanced Prosthodontics
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• v.13 no.5
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• pp.304-315
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• 2021

PURPOSE. Esthetic expectations have increased the use of polyetheretherketone (PEEK) clasps as alternatives to Cr-Co in removable partial dentures (RPDs). The objective of this study was to evaluate the retentive force and dimensional change of clasps with different thickness and undercut made from PEEK by the thermo-mechanical fatigue. MATERIALS AND METHODS. PEEK clasps (N = 48) with thicknesses of 1 or 1.50 mm and 48 premolar monolithic zirconia crowns with undercuts of 0.25 mm or 0.50 mm were fabricated. Samples are divided into four groups (C1-C4) and were subjected to 7200 thermal aging cycles (at 5 - 55℃). The changes in the retentive force and dimensions of the clasps were measured by micro-stress testing and micro-CT devices from five measurement points (M1 - M5). One-way ANOVA, paired t-test, two-way repeated ANOVA, and post-hoc tests were used to analyze the data (P < .05). RESULTS. The retentive forces of C1, C2, C3, and C4 groups in initial and final test were found to be 4.389-3.388 N, 4.67 - 3.396 N, 5.161 - 4.096 N, 5.459 - 4.141 N, respectively. The effects of retentive force of all PEEK clasps groups were significant decreased. Thermo-mechanical cycles caused significant dimensional changes at points with M2, M4, and M5, and abraded the clasp corners and increased the distance between the ends of the clasp, resulting in reduced retentive forces (P^* = .016, P^* = .042, P < .001, respectively). CONCLUSION. Thermo-mechanical aging decreases the retentive forces in PEEK clasps. Increasing the thickness and undercut amount of clasps decreases the amount of dimensional change. The values measured after aging are within the clinically acceptable limits.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.22 no.2
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• pp.215-219
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• 1992

The author ovserved a case of dentinogenesis imperfecta in a 8-year-old and a 9-year-old brother with complaints of abnormal morphologic changes of the teeth. 1. Clinically, yellowish brown colored teeth, fractured crown and numerous retained root tips of deciduous teeth with severe attrition were observed in the both deciduous and permanent dentitions. 2 Radiographically, small-sized teeth, partial or complete obliteration of the pulp chambers and pulp canals in the anterior teeth, partial obliteration of the pulp chambers and thin enamel in the permanent tooth germs were observed. 3. The familial history was their father has been lose his teeth early.

• Journal of the Korean Statistical Society
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• v.25 no.1
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• pp.111-122
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• 1996

A model for a system whose state changes continuously with time is introduced. It is assumed that the system is modeled by a Brownian motion with negative drift and an absorbing barrier at the origin. A repairman arrives according to a Poisson process and repairs the system according to an (s,S) policy, i.e., he increases the state of the system up to S if and only if the state is below s. A partial differential equation is derived for the distribution function of X(t), the state of the system at time t, and the Laplace-Stieltjes transform of the distribution function is obtained by solving the partial differential equation. For the stationary case the explicit expression is deduced for the distribution function of the stationary state of the system.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2002.11a
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• pp.325-328
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• 2002

The partial-discharge(PD) is accompanied by physical and chemical phenomena, such as heat, light, noise, gas, chemical transformation, electric current, and electromagnetic radiation. The PD can be detected by measuring one of these changes. Although some techniques are employed in this purpose, several obstacles interfere with an on-line measurement. Now a fiber-optic sensor for detecting ultrasonics is suggested for the on line measurement system with high accuracy. In this paper, an optical fiber sensor utilizing the principal of Mach-Zehnder interferometer was proposed to detect the discharge signal.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.729-732
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• 2001

In this study, the effect of oxygen partial pressure on the electrical properties of vanadium oxide(VO$_{x}$) thin films were investigated. The thin films were prepared by r.f. magnetron sputtering from V$_2$O$_{5}$ target in a gas mixture of argon and oxygen. The oxygen partial pressure ratio is changed from 0% to 8%. I-V characteristics were distinguished between linear and nonlinear region. In the low field region the conduction is due to Schottky emission, while at high fields it changes to Fowler-Nordheim tunneling type conduction. The conductivity measurements have shown an Arrhenius dependence of the conductivity on the temperature.ure.

• Environmental Mutagens and Carcinogens
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• v.8 no.1
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• pp.22-34
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• 1988

The biochemical changes of the hepatic tissues, induced by the carcinogen treatment such as diethylnitrosamine and acetamidofluorene in combination with the partial hepatectomy after Solt and Farber, were determined for the characterization of the induction of the proliferative capacity and the environmental adaptability of the carcinogenic tissues during the malignant transformation process. For the study of the proliferative capacity of the tissues, the activities of the enzymes, related with the nitrogen trapping mechanism, such as glutamine synthetase and gamma-glutamyltranspeptidase, were monitroed, while the cintents of cytochrome P450's and their isozymic patterns as well as the activities of the glutathione S-transferase were determined in the function of time after the hepatocarcinogenic stimuli.