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Development and Validation of a Predictive Model for Listeria monocytogenes Scott A as a Function of Temperature, pH, and Commercial Mixture of Potassium Lactate and Sodium Diacetate

  • Abou-Zeid, Khaled A.;Oscar, Thomas P.;Schwarz, Jurgen G.;Hashem, Fawzy M.;Whiting, Richard C.;Yoon, Kisun
    • Journal of Microbiology and Biotechnology
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    • v.19 no.7
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    • pp.718-726
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    • 2009
  • The objective of this study was to develop and validate secondary models that can predict growth parameters of L. monocytogenes Scott A as a function of concentrations (0-3%) of a commercial potassium lactate (PL) and sodium diacetate (SDA) mixture, pH (5.5-7.0), and temperature (4-37DC). A total of 120 growth curves were fitted to the Baranyi primary model that directly estimates lag time (LT) and specific growth rate (SGR). The effects of the variables on L. monocytogenes Scott A growth kinetics were modeled by response surface analysis using quadratic and cubic polynomial models of the natural logarithm transformation of both LT and SGR. Model performance was evaluated with dependent data and independent data using the prediction bias ($B_f$) and accuracy factors ($A_f$) as well as the acceptable prediction zone method [percentage of relative errors (%RE)]. Comparison of predicted versus observed values of SGR indicated that the cubic model fits better than the quadratic model, particularly at 4 and $10^{\circ}C$. The $B_f$and $A_f$for independent SGR were 1.00 and 1.08 for the cubic model and 1.08 and 1.16 for the quadratic model, respectively. For cubic and quadratic models, the %REs for the independent SGR data were 92.6 and 85.7, respectively. Both quadratic and cubic polynomial models for SGR and LT provided acceptable predictions of L. monocytogenes Scott A growth in the matrix of conditions described in the present study. Model performance can be more accurately evaluated with $B_f$and $A_f$and % RE together.

A Study of 3D Ore-Modeling by Integrated Analysis of Borehole and Geophysical Data (시추자료와 물리탐사자료의 복합해석을 통한 3차원 광체 모델링 연구)

  • Noh, Myounggun;Oh, Seokhoon;Ahn, Taegyu
    • Geophysics and Geophysical Exploration
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    • v.16 no.4
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    • pp.257-267
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    • 2013
  • 3-D ore modeling was performed to understand the configuration of ore bodies by integrated analysis of borehole and geophysical data in iron-mine area. Five representative indices of rocks were designated, which were obtained from geological survey and borehole. The five indices of rocks were geostatistically simulated by Sequential Indicator Simulation method to delineate boundary of the ore bodies. And Ordinary Kriging and Sequential Gaussian Simulation was applied to make secondary information using resistivity data from magnetotellurics and DC resistivity survey, and this information was used for simple kriging with local varying means, one of integrated kriging techniques. From the correlation analysis between each properties, it was found that high grade of ore is characterized by increased density, whereas the electrical resistivity decreases. With the integrated results of geophysical and borehole data, it was also found that the real configuration of ore body was similar to the modeled result and information about ore grade in 3-D space was obtained.

A STUDY OF THE TEMPOROMANDIBULAR JOINT IN NORMAL OCCLUSION USING T.M.J TOMOGRAM AND CEPHALOGRAM (단층 및 두부 방사선 계측사진을 이용한 정상교합자의 악관절에 관한 연구)

  • Baik, Hyoung-Seon
    • The korean journal of orthodontics
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    • v.16 no.1
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    • pp.85-106
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    • 1986
  • The purpose of this investigation was to know the means of the T.M.J. space and to compare spational differences in centric relation and centric occlusion by the T.M.J. Tomogram and to study the correlation between the articular eminence slope and the lingual surface slope of the maxillary central incisor by the Cephalogram in near normal occlusion subjects. These results could give contribution for the diagnosis of orthodontic treatment and T.M.J. dysfunction and the assessment of orthopedic treatment and orthognathic surgery. 44 young adults (28 men and 16 women, 21 to 27 years of age) were selected from the Dental students in Yonsei Univ. Criteria for selection was normal occlusion, no clinical signs and T.M.J. dysfunction, no history of orthodontic treatment, and no missing tooth. After submental vertex view analysis. each subject was given the T.M.J. Tomogram in centric relation and centric occlusion and the Cephalogram was given with Quint Sectograph. All data was recorded and statistically processed with the CYBER computer system. Results were analyzed: the following findings and conclusions were derived. 1. The mean value for the combined right and left anterior joint space was 2.549mm, the posterior space was 2.260mm, and superior space was 3.31mm in centric relation. The anterior space was 2.316mm, posterior space was 2.474mm, and superior space was 3.435mm in centric occlusion. 2. In the centric relation position, both condyles were placed more posterioly and superioly in their fossae than in the centric occlusion position by the spatial difference. 3. In the centric occlusion position, both condyles were more symmetrically placed in their fossae with equal anterior-posterioly rather than in the centric relation position. 4. The mean articular eminence angle was $48.19^{\circ}$ and the mean fossa height was 7.911mm. A strong positive correlation between the articular eminence angle and fossa height in T.M.J. Tomogram was found. 5. In Cephalometric analysis, there was a strong positive correlation between the articular eminence slope and the lingual surface slope of the upper central incisor to the FH plane, occlusal plane, and S-N plane. 6. There was moderate positive correlation between the S-E measurements and the fossa height, articular eminence angle, and DcGn < F-H.

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Low-Dose Docetaxel/Cisplatin - Leucovorin and 46 Hour Infusional Fluorouracil in Metastatic Gastric Carcinoma

  • Alici, Suleyman;Buyukberber, Suleyman;Alkis, Necati;Benekli, Mustafa;Ozkan, Metin;Bilici, Ahmet;Demirci, Umut;Karaca, Halit;Arpaci, Erkan;Gumus, Mahmut;Altunbas, Mustafa;Dane, Faysal;Turk, H. Mehmet;Anatolian Society of Medical Oncology
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.1
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    • pp.423-427
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    • 2013
  • Background: Phase II and III trials of docetaxel, cisplatin and fluorouracil (DCF) have shown superior efficacy versus cisplatin and fluorouracil alone but with high rates of hematologic toxicity in metastatic gastric cancer cases. To reduce toxicity while maintaining the efficacy of DCF, we investigated low dose docetaxel (D), cispatin (C) - leucovorin and fluorouracil (De Gramont regimen). Patient and methods: Chemotherapy-naïve patients with metastatic gastric cancer (MGC) received D 60 mg/$m^2$ on day 1 and cisplatin 30 mg/$m^2$ on day 1-2 and the De Gramont regimen (Folinic acid 400 mg/m2 on day 1 and 5-FU 2400 mg/$m^2$/46h continuous infusion) every 3 weeks. The primary endpoint was response rate. Results: One hundred twenty patients with a median age of 52.5 years (range, 32-78) received a median of 6 cycles (range, 2-12 cycles). Of the 120 evaluable patients, 4 showed complete remission and 36 achieved a partial response. The overall response rate was 56.6%. Twenty eight patients (23.3%) showed stable disease and 52 (43.3%) progression. The median time to progression was 7 months (95%CI 6-7.9). The median overall survival was 15 months (95%CI 13.7-16.2). The most frequent hematological toxicity was leucopenia, which occurred at grade 3/4 intensity in 24 patients (20%). Conclusions: Low-dose DC-De Gramont regimen is active in MGC with a tolerable toxicity profile.

Polarographic Behaviors of Copper and Cadmium Complexes with 2,2'-Bipyridine and Ethylenediamine in Acetonitrile (아세토니트릴에서 구리와 카드뮴의 2,2'-Bipyridine과 Ethylenediamine 착물에 대한 폴라로그래프적 연구)

  • Park, Du Won;Lee Heung Lark;Bae Zun Ung
    • Journal of the Korean Chemical Society
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    • v.18 no.3
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    • pp.202-209
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    • 1974
  • Polarographic behaviors of copper and cadmium complexes with 2,2'-bipyridine and ethylenediamine in acetonitrile have been investigated by the DC and AC polarography. The reduction processes are estimated as follows; $Cu(II)-bipy. \;complex\;{\longrightarrow^{e^-}_{E_{1/2}\risingdotseq+0.1V}}\;Cu(I)-bipy.\;complex\;{\longrightarrow^{e^-}_{E_{1/2}=-0.43V}}\;Cu(Hg)$$Cu(II)-en.\;complex\;{\longrightarrow^{e^-}}\;Cu(I)-en.\;complex\;{times}\;{\longrightarrow^{e^-}_{E_{1/2}=-0.56V}}\;Cu(Hg)$$Cu(II)-bipy. \;complex\;{\longrightarrow^{e^-}_{E_{1/2}=-0.57V}}\;Cu(I)-bipy.\;complex\;{\longrightarrow^{2e^-}_{E_{1/2}=-0.97V}}\;Cd(I)-bipy\;complex$$Cu(II)-en.\;complex\;{\longrightarrow^{e^-}_{E_{1/2}=+0.05V}\;Cu(I)-en.\;complex{\longrightarrow^{e^-}_{E_{1/2}=-0.92V}}\;Cu(Hg)$ The limiting currents of all steps are controlled by diffusion. The number of ligand and the dissociation constant for Cu(Ⅰ)-bipy. complex were found to be n = 2 and $K_d=(1.5{\pm}0.1){\times}10^{-7}$, respectively.

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Analysis and Mechanistic Investigation of Redox Process of 2-Amino-1-cyclopentene-1-dithiocarboxylate by Adsorptive Stripping Voltammetry on Glassy Carbon Electrode (Glassy Carbon 전극에서의 벗김 전압-전류법을 이용한 2-Amino-1-cyclopentene-1-dithiocarboxylate 의 분석과 전극 반응 메카니즘의 연구)

  • Yoon-Bo Shim;Duk-Soo Park;Sung-Nak Choi;Mi-Sook Won
    • Journal of the Korean Chemical Society
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    • v.32 no.1
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    • pp.37-47
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    • 1988
  • The electrochemical behavior of 2-Amino-1-cyclopentene-1-dithiocarboxylate (acdc) was investigated by the use of polarography, cyclic voltammetry and cathodic stripping voltammetry at glassy carbon electrode. In this study, it was found that the dimer of the acdc was deposited on the glassy carbon electrode via one-electron oxidation process at +0.25V vs. SCE. The ring formation between two dithio group occurs along with the elimination of one sulfur atom. The elimination of sulfur atom occurs via two electron oxidation process at +0.8V vs. SCE. The most sensitive cathodic stripping peak due to the formation of the dimer was observed at -0.85V vs. SCE. The peak relationship between current and concentration was fairly linear in the range of 3${\times}10^{-5}{\sim}1.0{\times}10^{-6}$M. The preconcentration procedure enhanced the sensitivity about 100 times for the analysis of acdc using diffusion current. Detection limit was found to be $2.5{\times}10^{-7}$M and relative standard deviation was ${\pm}$4.1 % at $5.0{\times}10^{-6}$M DC polarography.

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Ulcerative Colitis is Associated with Novel Polymorphisms in the Promoter Region of MIP-3${\alpha}$/CCL20 Gene

  • Choi, Suck-Chei;Lee, Eun-Kyung;Lee, Sung-Ga;Chae, Soo-Cheon;Lee, Myeung-Su;Seo, Geom-Seog;Kim, Sang-Wook;Yeom, Joo-Jin;Jun, Chang-Duk
    • IMMUNE NETWORK
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    • v.5 no.4
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    • pp.205-214
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    • 2005
  • Background: We examined global gene expression profiles of peripheral blood mononuclear cells (PBMCs) in patients with ulcerative colitis (DC), and tested whether the identified genes with the altered expression might be associated with susceptibility to UC. Methods: PBMCs from 8 UC and 8 normal healthy (NH) volunteers were collected, and total RNAs were subjected to the human 8.0K cDNA chip for the micro array analysis. Real time-PCR (RT-PCR) was performed to verify the results of micro array. One hundred forty UC patients and 300 NH controls were recruited for single nucleotide polymorphism (SNP) analysis. Results: Twenty-five immune function-related genes with over 2-fold expression were identified. Of these genes, two chemokines, namely, CXCL1 and CCL20, were selected because of their potential importance in the evocation of host innate and adaptive immunity. Four SNPs were identified in the promoter and coding regions of CXCL1, while there was no significant difference between all patients with UC and controls in their polymorphisms, except minor association at g.57A>G (rs2071425, p=0.02). On the other hand, among three novel and one known SNPs identified in the promoter region of CCL20, g. -1,706 G>A (p=0.000000055), g. -1,458 G>A (p=0.0048), and g. -962C>A (p=0.0006) were found to be significantly associated with the susceptibility of Uc. Conclusion: Altered gene expression in mononuclear cells may contribute to IBD pathogenesis. Although the findings need to be confirmed in other populations with larger numbers of patients, the current results demonstrated that polymorphisms in the promoter region of CCL20 are positively associated with the development of Uc.

Enhancement of Adenoviral Transduction and Immunogenecity of Transgenes by Soluble Coxsackie and Adenovirus Receptor-TAT Fusion Protein on Dendritic Cells

  • Kim, Hye-Sung;Park, Mi-Young;Park, Jung-Sun;Kim, Chang-Hyun;Kim, Sung-Guh;Oh, Seong-Taek;Kim, Tai-Gyu
    • IMMUNE NETWORK
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    • v.6 no.4
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    • pp.192-198
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    • 2006
  • Background: Investigating strategy to enhance efficiency of gene transfer via adenovirus is critical to sustain gene expression in targeted cells or tissues to regulate immune responses. However, the use of adenovirus as a gene delivery method has been limited by the native tropism of the virus. In this study, the critical parameter is to improve the efficient binding of viral particles to the plasma membrane prior to cellular uptake. Methods: Human immunodeficiency virus (HIV-1) trans-acting activator of transcription (TAT), a protein transduction domain, was fused to the ectodomain of the coxsackie-adenovirus receptor (CAR). The CAR-TAT protein was produced from a Drosophila Schneider 2 cells (S2) transfected with CAR-TAT genes. The function of CARTAT was analyzed the efficiency of adenoviral gene transfer by flow cytometry, and then immunizing AdVGFP with CAR-TAT was transduced on dendritic cells (DCs). Results: S2 transfectants secreting CAR-TAT fusion protein has been stable over a period of 6 months and its expression was verified by western blot. Addition of CAR-TAT induced higher transduction efficiency for AdVGFP at every MOI tested. When mice were vaccinated with DC of which adenoviral transduction was mediated by CAR-TAT, the number of IFN-${\gamma}$ secreting T-cells was increased as compared with those DCs transduced without CAR-TAT. Conclusion: Our data provide evidence that CAR-TAT fusion protein enhances adenoviral transduction and immunogenecity of transgenes on DCs and may influence on the development of adenoviral-mediated anti-tumor immunotherapy.

Moving Image Compression with Splitting Sub-blocks for Frame Difference Based on 3D-DCT (3D-DCT 기반 프레임 차분의 부블록 분할 동영상 압축)

  • Choi, Jae-Yoon;Park, Dong-Chun;Kim, Tae-Hyo
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.37 no.1
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    • pp.55-63
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    • 2000
  • This paper investigated the sub-region compression effect of the three dimensional DCT(3D-DCT) using the difference component(DC) of inter-frame in images. The proposed algorithm are the method that obtain compression effect to divide the information into subband after 3D-DCT, the data appear the type of cubic block(8${\times}$8${\times}$8) in eight difference components per unit. In the frequence domain that transform the eight differential component frames into eight DCT frames with components of both spatial and temporal frequencies of inter-frame, the image data are divided into frame component(8${\times}$8 block) of time-axis direction into 4${\times}$4 sub block in order to effectively obtain compression data because image components are concentrate in corner region with low-frequency of cubic block. Here, using the weight of sub block, we progressed compression ratio as consider to adaptive sub-region of low frequency part. In simulation, we estimated compression ratio, reconstructed image resolution(PSNR) with the simpler image and the complex image contained the higher frequency component. In the result, we could obtain the high compression effect of 30.36dB(average value in the complex-image) and 34.75dB(average value in the simple-image) in compression range of 0.04~0.05bpp.

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Fabrication and characterization of the 0.25 ${\mu}m$ T-shaped gate P-HEMT and its application for MMIC low noise amplifier (0.25 ${\mu}m$ T형 게이트 P-HEMT 제작 및 특성 평가와 MMIC 저잡음 증폭기에 응용)

  • Kim, Byung-Gyu;Kim, Young-Jin;Jeong, Yoon-Ha
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.36D no.1
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    • pp.38-46
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    • 1999
  • o.25${\mu}m$ T-shaped gate P-HEMT is fabricated and used for design of X0band three stage monolithic microwave integrated circuit(MMIC) low noise amplifier(LNA). The fabricated P-HEMT exhibits an extrinsis transconductance of 400mS/mm and a drain current of 400mA/mm. The RF and noise characteristics show that the current gain cut off frequency is 65GHz and minimum noise figure(NFmin) of 0.7dB with an associated gain of 14.8dB at 9GHz. In the design of the three stage LNA, we have used the inductive series feedback circuit topology with the short stub. The effects of series feedback to the noise figure, the gain, and the stability have been investigated to find the optimal short stub length. The designed three staage LNA showed a gain of above 33dB, a noise figure of under 1.2dB, and ainput/output return loss of under 15dB and 14dB, respectively. The results show that the fabricated P-HEMT is very suitable for a X-band LNA with high gain.

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