• Toxicological Research
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• v.17 no.4
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• pp.309-316
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• 2001

Male Sprague Dawley rats were exposed to 0, 0.04, 0.2, and 0.8% Pb acetate in drinking water for 13 weeks and fed a commercial diet. Dose-related adverse effects observed at the end of the Pb acetate exposure in the drinking water were as follows: decrease in body weight gain, decrease in hemoglobin, hematocrit(HCT), mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH), increase in serum glucose, decrease in serum testosterone, increase in lead accumulation and $\delta$-ALA release in urine, and decrease in $\delta$-ALAD activities DNA content and histopathlogy (intranuclear inclusion body in kidney proximal tubule cell). Taken together, repeated exposure of lead acetate induced toxicities in hematopoietic system, especially testis and kidney.

• KSBB Journal
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• v.5 no.4
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• pp.403-410
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• 1990

Application of the Rheocatch Hotwire Monitoring System for food biotechnology process was evaluated. The growth of microogranism, E coli (JM 83 and Sigma) and Corynesccfertun glutamicum, were monitored. in the fermentor. The cell growth could not be detected the temperature differences between the hotwire and samples($\Delta$T) as indicated by the monitoring system during the fermentation processes. The cell concentration of less than 2g/dl was not sufficient to generate the measurable temperature difference in the fermentor. In order to calibrate the Rheocatch Monitoring System, the temperature difference as a function of solute concentration (microbial cells, sodium cholide, sucrose and dextran) was studied. The relationship between $\Delta$T and the concentration of microbial cells, sucrose and dextran can be expressed in a power series. Further studied with dextran indicated that viscosity and/or kinematic viscosity increase exponentially with an increase in $\Delta$T This is regardless of the concentration and molecular weight of dextran. $\Delta$T linearly increases with the logarithm of molecular weight, while the logarithm of viscosity and the logarithm of kinematic viscosity increase with the logarithm of molecular weight.

• Journal of applied mathematics & informatics
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• v.23 no.1_2
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• pp.153-165
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• 2007

This paper deals with the empirical Bayes two-action problem of testing $H_0\;:\;{\theta}{\leq}{\theta}_0$: versus $H_1\;:\;{\theta}>{\theta}_0$ using a linear error loss for some discrete nonexponential families having probability function either $$f_1(x{\mid}{\theta})=(x{\alpha}+1-{\theta}){\theta}^x\prod\limits_{j=0}^x\;(j{\alpha}+1)$$ or $$f_2(x{\mid}{\theta})=[{\theta}\prod\limits_{j=0}^{x-1}(j{\alpha}+1-{\theta})]/[\prod\limits_{j=0}^x\;(j{\alpha}+1)]$$. Two empirical Bayes tests ${\delta}_n^*\;and\;{\delta}_n^{**}$ are constructed. We have shown that both ${\delta}_n^*\;and\;{\delta}_n^{**}$ are asymptotically optimal, and their regrets converge to zero at an exponential decay rate O(exp(-cn)) for some c>0, where n is the number of historical data available when the present decision problem is considered.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.361-364
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• 2003

In this paper, a high-resolution multibit sigma-delta modulator implemented in a.0.35-um CMOS technology is introduced. This modulator consists of two switched capacitor integrators, 3-bits A/D converter, and 3-bits D/A converter For the verification of the internal function blocks, HSPICE simulator is used. This circuit is normally operated at 130 MHz clock and the total power dissapation is 70 mW.

• Korean Journal of Optics and Photonics
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• v.7 no.4
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• pp.434-439
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• 1996

To investigate influence of the incident beams which have the truncated Gaussian amplitude and of the shapes of bump on read-out signal is an optical disc, and the point spread function on bump, the scalar diffraction theory is used in this paper. We consider the truncated Gaussian amplitudes which are $\sigma$=0, 0.5, 1.5, and 2.5, the height of bump which is given by $n{\Delta}_0={\lambda}/4$, and the phase height of bump which is then given by ${\Phi}_0={\pi}$. We also consider the shapes of the bump which are a rectangular shape, a frustoconical shape, and a conical shape. It is shown that as the truncation of incident beam reduces the radius of central spot on bump decreases, the maximum value of read-out signal increases, and that the size of bump decreases. From these results, we get better read-out signal and the reduced cross-talk in optical disc when the truncation of incident beam reduces. Therefore a laser beam having less truncated Gaussian amplitude may useful for an actual optical disc.

• Reproductive and Developmental Biology
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• v.33 no.2
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• pp.77-83
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• 2009

Erythropoietin (EPO), a glycoprotein hormone produced from primarily cells of the peritubular capillary endothelium of the kidney, is responsible for the regulation of red blood cell production. We have been investigating the roles of glycosylation site added in the biosynthesis and function of recombinant protein. We constructed three EPO mutants ($\Delta$69, $\Delta$105 and $\Delta$69,105), containing an additional oligosaccharide chains. EPOWT and EPO$\Delta$69 were effectively expressed in transient and stably transfected CHO-K1 cell lines. But, it wasn't detected any protein in the culture medium of EPO$\Delta$105 and EPO$\Delta$69,105 mutants. The growth and differentiation of EPO-dependent human leukemic cell line (F36E) were used to measure the cytokine dependency and in vitro bioactivity of rec-hEPO. MTT assay values were increased by survival of F36E cells at 24h. To analysis biological activity in vivo, two groups of ICR-mice (7 weeks old) were injected subcutaneously with 10 IU per mice of rec-hEPO molecules on days 0 and 2. Red blood cell and hematocrit values were measured on 6 days after the first injection. The hematocrit values were remarkably increased in all treatment groups. The pharmacokinetic analysis was also affected in the mice injected with rec-hEPO molecules 2.5 IU by tail intravenous. Protein samples were detected by Western blotting. An EPO$\Delta$69 protein migrated as a broad band with an average apparent molecular and detected slightly high band. Enzymatic N-deglycosylation resulted in narrow band and was the same molecular size. The biological activity of EPO$\Delta$69 was enhanced to compare with wt-hEPO. The half-life was longer than wt-hEPO. The results suggest that hyperglycosyalted recombinant human erythropoietin (EPO$\Delta$69) may have important biological and therapeutic good points.

• Journal of The Korean Astronomical Society
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• v.33 no.2
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• pp.89-95
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• 2000

As an efficient method to detect blending of general gravitational microlensing events, it is proposed to measure the shift of source star image centroid caused by microlensing. The conventional method to detect blending by this method is measuring the difference between the positions of the source star image point spread function measured on the images taken before and during the event (the PSF centroid shift, ${\delta}{\theta}$c,PSF). In this paper, we investigate the difference between the centroid positions measured on the reference and the subtracted images obtained by using the difference image analysis method (DIA centroid shift, ${\delta}{\theta}$c.DIA), and evaluate its relative usefulness in detecting blending over the conventional method based on ${\delta}{\theta}$c,PSF measurements. From this investigation, we find that the DIA centroid shift of an event is always larger than the PSF centroid shift. We also find that while ${\delta}{\theta}$c,PSF becomes smaller as the event amplification decreases, ${\delta}{\theta}$c.DIA remains constant regardless of the amplification. In addition, while ${\delta}{\theta}$c,DIA linearly increases with the increasing value of the blended light fraction, ${\delta}{\theta}$c,PSF peaks at a certain value of the blended light fraction and then eventually decreases as the fraction further increases. Therefore, measurements of ${\delta}{\theta}$c,DIA instead of ${\delta}{\theta}$c,PSF will be an even more efficient method to detect the blending effect of especially of highly blended events, for which the uncertainties in the determined time scales are high, as well as of low amplification events, for which the current method is highly inefficient.

• Communications for Statistical Applications and Methods
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• v.2 no.2
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• pp.43-51
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• 1995

For the stress-strengh function, hierarchical Bayes estimations considered under squared error loss and entropy loss. In particular, the desired marginal postrior densities ate obtained via Gibbs sampler, an iterative Monte Carlo method, and Normal approximation (by Delta method). A simulation is presented.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2005.04a
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• pp.147-148
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• 2005

In this paper we study Laplace transform of the fuzzy Dirac delta function and the examples of fuzzy impulsive differential equations.

• Journal of Korean society of Dental Hygiene
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• v.19 no.3
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• pp.351-362
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• 2019

Objectives: The study aimed to analyze the factors affecting the maturity of dental biofilm, which was assessed with quantitative light-induced fluorescence-digital(QLF-D), in a sample of Korean older adults. Methods: This cross-sectional study included 67 participants, aged 65 years and older. All participants completed a questionnaire and tests to measure their manual dexterity and handgrip strength, which are parameters that indicate hand function abilities. To evaluate dental biofilm maturity, 804 surfaces of six index teeth were imaged using QLF-D and then quantified as ${\Delta}R$ values. All data were collected from May 25, 2017 to April 30, 2018. The independent t-test, one-way analysis of variance, and step-wise multiple linear regression were performed to analyze the factors associated with the maturity of dental biofilm (${\Delta}R$). Results: The multivariate linear regression analysis revealed that the factor most strongly related to dental biofilm maturity(${\Delta}R$) was manual dexterity (${\beta}=-0.326$), followed by handgrip strength (${\beta}=-0.303$) and use of interdental cleaning devices (${\beta}=-0.283$) (p<0.05). Conclusions: Manual dexterity, handgrip strength, and use of interdental cleaning devices are factors that can predict dental biofilm maturity in adults aged 65 years or older. Therefore, the hand function of a patient should be evaluated first, before assessing the oral hygiene status of the patient or providing him/her with oral health education, and the dental hygienist should provide differentiated oral hygiene care depending on the patient's hand function ability. Finally, dental hygienists should help older adults to recognize the importance of auxiliary oral hygiene devices such as interdental brushes and keep motivating them to use the devices more frequently.