• Korean Chemical Engineering Research
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• v.50 no.5
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• pp.913-922
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• 2012

Grasp of characteristics within liquid-liquid agitated vessel are very important to environment and chemical industry. Mass transfer volumetric coefficient and the Sauter mean diameter of near the droplet were measured by varying the impeller position and liquid height using the alkaline hydrolysis reaction of esters. As a result, following their good correlation was obtained. $$d_{32}=0.270\(\frac{{\sigma}^{0.6}}{{\rho}^{0.2}P^{0.4}_{Vi}}\)k_La=0.49\(\frac{6{\phi}D_A}{d^2_{32}}\)\(\frac{P_Vd^4_{32}}{{\rho}v^3}\)^{0.193}Sc^{1/3}$$.

• Journal of Microbiology and Biotechnology
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• v.16 no.9
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• pp.1434-1440
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• 2006

The stable anchorage of pyridoxal 5'-phosphate (PLP) in the active site of D-amino acid transaminase (D-AT) is crucial for the enzyme catalysis. The three-dimensional structure of D-AT revealed that Glu32 is one of the active site groups that may playa role in PLP binding. To prove the role of Glu32 in PLP stability, we firstly checked the rate of the potential rate-limiting step. The kinetic analysis showed that the rate of the ${\alpha}$-deprotonation step reduced to 26-folds in E32A mutant enzyme. Spectral analyses of the reaction of D-AT with D-serine revealed that the E32A mutant enzyme failed to stabilize the key enzyme-substrate intermediate, namely a quinonoid intermediate (E-Q). Finally, analysis of circular dichroism (CD) on the wild-type and E32A mutant enzymes showed that the optical activity of PLP in the enzyme active site was lost by the removal of the carboxylic group, proving that Glu32 is indeed involved in the cofactor anchorage. The results suggested that the electrostatic interaction network through the groups from PLP, Glu32, His47, and Arg50, which was observed from the three-dimensional structure of the enzyme, plays a crucial role in the stable anchorage of the cofactor to give necessary torsion to the plane of the cofactor-substrate complex.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.10
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• pp.4643-4646
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• 2016

The CC chemokine receptor 5 (CCR5) delta 32 allele results in a nonfunctional form of the chemokine receptor and has been implicated in a variety of immune-mediated diseases. $CCR5{\Delta}32$ may also predispose one to chronic liver disease or be linked with resistance to HBV infection. This study was undertaken to investigate any association between CCR5 polymorphism with resistance to hepatitis B or susceptibility to HBV infection. A total of 812 Iranian individuals were enrolled into two groups: HBV infected cases (n=357), who were HBsAg-positive, and healthy controls (n=455). We assessed polymorphisms in the CCR5 gene using specific CCR5 oligonucleotide primers surrounding the breakpoint deletion. Genotype distributions of the HBV infected cases and healthy controls were determined and compared. The CCR5/CCR5 (WW) and $CCR5/CCR5{\Delta}32$ (W/D) genotypes were found in (98%) and (2%) of HBV infected cases, respectively. The $CCR5{\Delta}32/{\Delta}32$genotype was not found in HBV infected cases. Genotype distributions of CCR5 in healthy controls were W/W genotype in (87.3%), W/D genotype in (11.2%) and D/D genotype in (1.5%). Heterozygosity for $CCR5/CCR5{\Delta}32$ (W/D) in healthy controls was greater than in HBV infected cases (11.2% vs 2%, p < 0.001). W/D and D/D genotypes were more prominent in healthy controls than in HBV infected cases. This study provides evidence that the $CCR5{\Delta}32$ polymorphism may have a protective effect in resistance to HBV infection at least in the Iranian population.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.34D no.4
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• pp.62-72
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• 1997

The optical power splitter/couplers based on MMI(multimode interference) in GaAs/AlGaAs are studied. We presetn a design of optical power splitter/couplers, which have deeply etched multimode waveguide. The properties and fabrication tolerance on the etching depth, multimode waveguide width are simulatedusing a FD-BPM (finite difference beam propgation method). Proposed 1*N optical of designed device is 0.7dB smaller than the optical power splitter with a shallowly etched MMI section. For 0.5dB excess loss, the predicted fabrication tolerance is 0.6.mu.m on the multimode waveguide width of the 14 optical power splitter with a deeply etched MMI section. Also excess loss and uniformity of poposed 32*32 optical power coupler are below 0.3dB. The excess loss of proposed 32*32 optical power coupler is 2dB smaller than the optical power coupler with a shallowly etched MMI section. It is shown that the optical power splitters/couplers with a deeply etched mMI section have low loss, good uniformity, and improved fabriction tolerance.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.8
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• pp.2003-2012
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• 1996

The 16- and 32-state Trellis-coded M-ary 4-dimensional (4-D) orthogonal modulation scheme with a frequency-reuse technique have been investigated. Here, 5 coded bits form a rate 4/5 convolutional encoder provide 32 possible symbols. Then the signals are mapped by a M-ary 4-D orthogonal modulator, where each signal has equal energy and is PSK modulated. In the M-ary 4-D modulator, we have employed the vectors which is derived by the optimization technique of signal waveforms in a 4-D sphere. This technique is usedin maximizing the minimum Euclidean distance between a set of signal poits on a multidimensional sphere. By combinig trellis coding with M-ary 4-D modulation and proper set-partitioning, we have obtained a considerable impeovement in the free minimum distance of the system over an AWGN channel. The 16-state scheme obtains coding gains up to 5.5 dB over the uncoded two-independent QPSK scheme and 2.5 dB over the two-independent 2-D TCM scheme. And, the 32-state scheme obtains coding gains up to 6.4 dB over the uncoded two-independent QPSK schemeand 3.4 dB over the two-independent 2-D TCM scheme.

• Journal of the Korean Chemical Society
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• v.42 no.6
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• pp.672-678
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• 1998

Chitin was extracted from crab shell of Portuns triberculatus and deacethylated to yield chitosan with various molecular weights. The absorption and the fluorescence spectra of Rhodamine 6G(Rh 6G)-sodium dodecyl sulfate(SDS) and Rh 6G-chitosan systems were obtained. From the spectra, we observed that the absorption and the fluorescence intensity of Rh 6G-SDS system decreased when S/D(the concentration of SDS to that of Rh 6G ratio) was below or at 32, while they increased when S/D was above 32. From the suspended solid(SS) removal rate and the transmittance of Rh 6G-SDS-chitosan system, we found that when S/D ratio was 32 its flocculating behaviour was much stronger than Rh 6G-SDS system. As the concentration and the molecular weight of chitosan increased, we also found that S/D range was extended from 32 to 100. With increasing the molecular weight of chitosan, the SS removal rate increased around pH 2~9 but decreased remarkably at pH>12.

• Journal of Genetic Medicine
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• v.18 no.1
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• pp.64-69
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• 2021

Primary cilium has a signal transduction function that is essential for brain development, and also determines cell polarity and acts as a mediator for important signaling systems, especially the Sonic Hedgehog (SHH) pathway. TBC1D32 is a ciliary protein, implicated in SHH signaling. Biallelic mutations in the TBC1D32 gene causes a kind of ciliopathy, heterogeneous developmental or degenerative disorders that affect multiple organs, including the brain. Here we report a boy who carried compound heterozygous variants in TBC1D32. The patient showed hypotonia, respiratory difficulty, and multiple anomalies at his birth. He was diagnosed with congenital hypopituitarism and treated with T4, hydrocortisone, and growth hormone. Despite the hormonal replacement, the patient needed long-term respiratory support with tracheostomy and nutritional support with a feeding tube. His developmental milestones were severely retarded. Hydrocephalus and strabismus developed and both required surgery, during the outpatient follow-up. Whole-exome sequencing indicated compound heterozygous variants, c.2200C>T (p.Arg734^*) and c.156-1G>T, in TBC1D32 gene. This is the first Korean case of TBC1D32-related ciliopathy and we reported detailed and sequential clinical features. This case demonstrated the utility of whole-exome sequencing and provided valuable clinical data on ultra-rare disease.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2002.10a
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• pp.32-32
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• 2002

• Proceedings of the Korea Institute of Convergence Signal Processing
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• 2003.06a
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• pp.110-113
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• 2003

In this paper, the multi-channel high speed data acquisition system is implemented. This high speed signal processing system for 3-D image display is applicable to the manipulation of a medical image processing, multimedia data and various fields of digital image processing. In order to convert the analog signal into digital one, A/D conversion circuit is designed. PCI interface method is designed and implemented, which is capable of transmission a large amount of data to computer. In order to, especially, channel extendibility of images acquisition, bus communication method is selected. By using this bus method, we can interface each module effectively. In this paper, 32-channel A/D conversion and PCI interface system for 3-dimensional and real-time display of the retina image is developed. The 32-channel image acquisition system and high speed data transmission system developed in this paper is applicable to not only medical image processing as 3-D representation of retina image but also various fields of industrial image processing in which the multi-point realtime image acquisition system is needed.

• Proceedings of the KIEE Conference
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• 1984.07a
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• pp.103-106
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• 1984