• Journal of Microbiology and Biotechnology
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• v.19 no.11
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• pp.1281-1287
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• 2009

The distribution pattern of the phylum Acidobacteria, a previously uncultured bacterial group, was investigated by molecular ecological analyses of global soil samples collected from pristine ecosystems across five continents. Acidobacterial 16S rDNAs were observed in almost all soil samples, and members of acidobacterial primer group A were detected in all samples that harbored the phylum Acidobacteria. Other primer groups, Y, G, and O, showed limited distribution patterns. We further divided the primer groups into acidobacterial subdivisions (class-level). Subdivisional distribution patterns were determined by comparing the observed T-RFs with theoretical T-RFs predicted by in silico digestion of acidobacterial 16S rDNAs. Consistent with the PCR results obtained with subgroup-specific primers, T-RFLP analyses showed that acidobacterial subdivision 1 belonging to primer group A was present in the majority of the soil samples. This study revealed that the phylum Acidobacteria could be globally distributed. At the subdivisional level, acidobacterial subdivision 1 might be the most widely distributed group in this phylum, indicating that members of subdivision 1 might be adapted to various soil environments, and members belonging to other subdivisions might be restricted to certain geographic regions or habitats.

• Korean Journal of Food Science and Technology
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• v.40 no.4
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• pp.470-473
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• 2008

This study examined the enzymatic digestion, average molecular weight distribution and structural changes of Bombyx mori silk gland fibroin using gel penneation chromatography and nuclear magnetic resonance methods. The pure-separation of calcium chloride-treated fibroin hydrolysates was carried out by gel filtration chromatography. Also, the effects of fibroin's enzymatic hydrolysis were investigated using an edible enzyme. The average molecular weight of three hydrolysate samples (silk gland fibroin (SF), SF-calcium chloride (SFC), and SFC-enzyme) were measured to compare their characteristics. The molecular weights of SF, SFC, and SFC-enzyme were approximately 108,000, 65,000, and 1,000 Da, respectively. Finally, we determined the structural characteristic changes of the different enzymatically digested samples by $^{13}C$ nuclear magnetic resonance methods. For the enzymatically digested fibroin, the glycine $^{13}C^{\alpha}$ resonance indicated that the amino acid was dramatically changed and/or separated out; however, this was not shown for the normal Bombyx mori silk gland fibroin.

• Applied Chemistry for Engineering
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• v.4 no.3
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• pp.627-636
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• 1993

Anionic acrylic resin utilizing macromer(TBMA-g-MMA) copolymer was synthesized by preparing (TBMA) macromer using anionic living polymerization, followed by graft copolymerization with MMA macromer. To control the anionic site content in graft copolymer, the relative composition((TBMA) macromer/MMA ratio) of the graft copolymer was controlled at 7/3, 10/90, 15/85, 20/80, 30/70, 40/60, 50/50 in weight content. In the course of anionic living polymerization of(TBMA) macromer, broad molecular weight distribution (1.4~1.5) was obtained by using n-butyllithium-diphenyethylene initiatior system at $-78^{\circ}C$. To introduce the double bond at the end of chain in termination step, methacryloyl chloride was reacted after insertion of benzaldehyde as capping material. Moreover, TBMA parts in graft copolymer were hydrolyzed in the presence of p-toluenesulfonic acid catalyst, and neutralization of graft copolymer with triethylamine was granted acrylic resin to anionic site. Molecular weight and molecular weight distribution of(TBMA) macromer were determined by GPC, and the hydrolysis of TBMA with neutralization of acrylic resin were determined by IR and NMR. From water dispersion and stability point of view, stable dispersion state appeared at low molecular weight(TBMA) macromer with a small TBMA content as a result of scrutiny about the relation to TBMA content and branch length for(TBMA) macromer molecular weight in graft copolymer.

• Journal of Animal Environmental Science
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• v.10 no.1
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• pp.29-36
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• 2004

These experiments were conducted to analyze the characteristics of organic compounds and molecular weight distribution according to the treatment steps of purifying system for pig wastewater. The results obtained are summarized as follow. 1. Raw pig wastewater contained 31 kinds of organic compounds such as acetic acid, 2-butanone, hexane, chloroform, propionic acid, butanoic acid etc. 2. After ozone treatment, 13 kinds of organic compounds such as ethene, pentane, 2-methylopropanal, hexane, furan and so on were detected in the wastewater. 3. After $TiO_2$ treatment, 12 kinds of organic compounds such as ethene, hexane, chloroform, 1-decene, silane and so on were detected from the effluent. 4. After both ozone and $TiO_2$ treatment, portion of molecular weight smaller than 500 Daltons and molecular weight between 500 to 1,000 Daltons in the wastewater increased.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6769-6772
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• 2015

Background: High risk human papillomaviruses (HPVs) are the leading cause of cervical cancer (CC) and Pap smear screening has not been successful in preventing CC in Tunisia. HPV vaccination that targets HPV16 and 18 offers a new efficient prevention tool. Identification of HPV types in CC is thus essential to determine the impact of HPV vaccine implementation. The aim of this study is to provide specific data from Tunisia. Materials and Methods: A total of 89 histological confirmed paraffin embedded samples isolated from patients with CC diagnosed between 2001 and 2011 were collected from five medical centres from Northern and Southern Tunisia. HPV DNA was detected using a nested PCR (MY09/MY11-GP5+/GP6+) and genotyping was assessed using a reverse blot line hybridisation assay that enables the detection of 32 HPV types. Results: HPV DNA was detected in all samples. Twelve high risk types were detected; HPV16 and/or 18 were predominant, accounting together for 92.1% of all the CC cases (HPV16: 83.1%). Single infections accounted for 48.8% of the cases and were mostly linked to HPV 16 (32.6%) and less frequently to HPV 18 (2.4%). The other high risk HPV single infections were linked to HPV 35 (4.6%), 45 (4.6%), 58 (2.3%) and 59 (2.3%). Multiple infections with mixing of 2 to 4 genotypes predominately featrued HPV16 and/or 18 with HPV 35 and 45 (96.6 %) and less frequently with HPV 59, 40, 66, 73 and 58. There was no statistically significant variation in the relative distribution of HPV types with age. Conclusions: These results strongly indicate that prophylactic HPV vaccines can have a major impact in preventing CC in Tunisia.

• Journal of the Korean Chemical Society
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• v.53 no.6
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• pp.653-662
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• 2009

Developing effective tools for predicting absorption, distribution, metabolism, excretion properties and toxicity (ADME/T) of new chemical entities in the early stage of drug design is one of the most important tasks in drug discovery and development today. As one of these attempts, support vector machines (SVM) has recently been exploited for the prediction of ADME/T related properties. However, two problems in SVM modeling, i.e. feature selection and parameters setting, are still far from solved. The two problems have been shown to be crucial to the efficiency and accuracy of SVM classification. In particular, the feature selection and optimal SVM parameters setting influence each other, which indicates that they should be dealt with simultaneously. In this account, we present an integrated practical solution, in which genetic-based algorithm (GA) is used for feature selection and grid search (GS) method for parameters optimization. hERG ion-channel inhibitor classification models of ADME/T related properties has been built for assessing and testing the proposed GA-GS-SVM. We generated 6 different models that are 3 different single models and 3 different ensemble models using training set - 1891 compounds and validated with external test set - 175 compounds. We compared single model with ensemble model to solve data imbalance problems. It was able to improve accuracy of prediction to use ensemble model.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.5
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• pp.712-720
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• 2009

The goal of this study was to elucidate the expression and segmental distribution of the glomerular cationic amino acid metabolism transporter-2 (CAT-2) and thus to improve our understanding of porcine cationic amino acid transporters and amino acid absorption. Porcine CAT-2 was cloned, sequenced and characterized. The predicted amino acid sequence of porcine CAT-2 shared 86.1% and 92.1% identity with human and mouse CAT-2A, respectively. The tissue distribution patterns and ontogenic changes of CAT-2 mRNAs were determined by real-time Q-PCR. The results showed that porcine CAT-2 was highly expressed in the heart and intestinal tract (duodenum, ileum and jejunum). In addition, the mRNA of CAT-2 was found in liver, lung, kidney, brain and muscle. Within the intestinal tract, CAT-2 mRNA was most abundant in the ileum and rarely expressed in the duodenum. In the duodenum, the levels of CAT-2 mRNA reached their peak on day 7 (p<0.05) while in the jejunum, levels were low on day 1 and 7 and increased rapidly after day 26 before peaking on days 30 and 60 (p<0.05). The levels then dramatically decreased by day 90 (p<0.05). In the ileum, levels achieved their maximum on day 30 and then decreased significantly on day 60 (p<0.05).

• Journal of Environmental Science International
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• v.14 no.2
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• pp.105-119
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• 2005

The surface sediments inside Songsanpo and Seogwipo Harbors, major harbors of Jeju Island, were collected three times (June, September and December, 2001) and analyzed for 16 polycyclic aromatic hydrocarbons (PAHs) recommended by US-EPA as priority pollutants to assess their distribution levels and their biological effects on the marine organisms, and to suggest their possible origins. The concentrations of total PAHs inside Songsanpo and Seogwipo Harbors ranged from 41 to 288 ng/g on a dry weight basis with a mean value of 121 ng/g and from 14 to 268 ng/g with a mean value of 119 ng/g, respectively, and the levels were low as compared with those in other areas of the world. The sedimentary PAHs may be correlated with organic carbon and mud content to some extent. Based on comparisons of individual and total concentrations with effects-based sediment quality guidelines, the potential for the biological effects on the marine organisms were expected to be very low. From the examinations of the four PAH origin indices, such as LMW /HMW (low molecular weight 2-3 ring PAHs over high molecular weight 4-6 ring PAHs), phenanthrene/anthracene ratio, fluoranthene/pyrene ratio, chrysene/benzo[a]anthracene ratio, it can be concluded that the sediment PAH contaminations were ascribed to both of pyrolytic and petrogenic origins.

• Korea-Australia Rheology Journal
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• v.17 no.3
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• pp.125-130
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• 2005

Coalescence process of binary immiscible fluid mixtures having bimodal size distributions, prepared by mixing two pre-sheared samples at different shear rates, ${\gamma}_{pre1}\;and\;{\gamma}_{pre2}$, under shear flow at a final shear rate, ${\gamma}_f$, are examined by transient shear stress measurements and microscopic observations in comparison with the results for simply pre-sheared samples having narrow size distributions (unimodal distribution samples). Component fluids are a silicone oil (PDMS) and a hydrocarbon-formaldehyde resin (Genelite) and their viscosities are 14.1 and 21.0 $pa{\cdot}sec$ at room temperature $(ca.\;20^{\circ}C)$, respectively. The weight ratio of PDMS: Genelite was 7:3. Three cases, $({\gamma}_{pre1}=7.2sec^{-1},\;{\gamma}_{pre2}=12.0sec^{-1}\;and\;{\gamma}_f=2.4sec^{-1}),\;({\gamma}_{pre1}=0.8sec^{-1},\;{\gamma}_{pre2}=4.0sec^{-1}\;and\;{\gamma}_f=2.4sec^{-1}),\;and\;({\gamma}_{pre1}=7.2sec^{-1},\;{\gamma}_{pre2}=12.0^sec^{-1}\;and\;{\gamma}_f=7.2sec^{-1})$ the first case, transient shear stress did not show any significant difference but domains larger than the initial state are observed at short times. In the latter cases, there exist undershoot of shear stress, reflecting existence of deformed large domains, which is confirmed by the direct observation. It is concluded that coalescence between large and small domains more frequently occur than coalescence between the domains with similar size in the bimodal distribution samples.

• The Korean Journal of Ecology
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• v.11 no.1
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• pp.29-36
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• 1988

This present study has been carried out to examine the correlation between the distribution of the coliform bacterial plasmids and the viability test against heavy metals in the upper stream of Han river(Gapyung; clean water) and the its basin (Anyang Cheon; polluted water). And the distribution of plasmids were examined to be used as trophic indicator for analysis between the clean and polluted waters. 1. A total of 110 isolates were analyzed for the presence of plasmids by means of the boiling method and agarose gel techniques. Plasmids were significantly more frequent in the strains which had been isolated from the clean water (14.3%). Also, there were much higher multiplicity of plasmids at the polluted water(41.0%), compared with the clean water (33.0%). By the comparision between molecular weight of bacterial plasmids in the clean water and those of polluted water, there were no significant differences of the clean water from the polluted water, to such extent as 30.0%, 28.6%, respectively, in frequency for occurrence of high molecular weight plasmids iver 35.8% Mdal. 2. Each isolate was carried out the resistance test for mercury(10-5M), nickel(10-3M) and arsenic (0.1%). At the polluted site, the survival ability of the plasmid-carrying straings(Hg, 31.0%l Ni, 5.7%; As, 65.7%) was higher than that of the non plasmid-carrying strains(Hg, 12.1%; Ni, 3.0%; As, 54.6%). This trend was more remarkable in the clean site (plasmid-carrying strains: 16.7%,-,-). As a result it is suggested that plasmids could be used as an indicator of a certain types of water pollution. In addition, heavy metals might have inflyenced, some extent, to the distribution of plasmids in the environment which has been surveyed in the present study.