• Elastomers and Composites
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• v.34 no.4
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• pp.332-340
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• 1999

Hydrogenations of BR and NR performed by a noncatalytic method using p-toluenesulphonylhydrazide were carried out by reactive processing. The experimental procedures for carrying out the reaction were established. Two steps comprising premixing of the rubber with TSH followed by hydrogenation in compression mould were proved to be suitable. The percentages of hydrogenation attained by reactive processing were higher than those of the reaction carried out in solution at the same [TSH]/[C=C] ratio, reaction temperature and time. In-creasing the reaction temperature and reaction time resulted in increases of the percentage of hydrogenation. For BR, the maximum percentage of hydrogenation obtained was 36% at [TSH]/[C=C]=1/1.5. For NR, the highest percentage of hydrogenation was 34% at [TSH]/[C=C]=1/1.5. Cis-trans isomerisation was also observed to occur during hydrogenation of both BR and NR. Thermal stabilities of the hydrogenated BR and NR were shown to improve over those or the unhydrogenated counterparts.

• Applied Biological Chemistry
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• v.33 no.4
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• pp.343-348
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• 1990

E. coli LE392, transformed with CDDP-treated pBR322 DNA, was plated on ampicillin containing media. The number of colonies formed on ampicillin containing agar plate was reduced to undetectable level after treat the DNA with 13.3 ${\mu}M$ CDDP. The CDDP-treated pBR322 DNA was susceptible to sing1e strand DNA specific S1 nuclease and it's migration Pattern in agarose gel electrophoresis was changed. These results suggest that CDDP adduction to pBR322 DNA resulted in denaturation of the double helix and changes in it's conformation which ultimately leads In the inactivation of the ampicillin resistant sere.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.332-332
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• 2006

Well difined sulfonated styrene and n-butyl acrylate (nBA) block copolymers were synthesized by CuBr catalyzed living radical polymerization followed by acification by thermolysis. Neopentyl styrene sulfonate (NSS) was polymerized with PnBA macroinitator precursor ($M_{n}=19,500,\;PDI\;<\;1.09$) and CuBr catalyst with N,N,N',N' -pentamethylethyleneamine (PMDETA) to give nBA-NSS block copolymer with narrow polydispersity ($M_{n}=29,900,\;PDI\;<\;1.15$). PNSS segments in the block copolymer were then acidified by thermolysis at $150^{\circ}C$ resulting in polystyrene segments with 100 % sulfonic acid groups.

• Journal of Microbiology and Biotechnology
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• v.20 no.12
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• pp.1689-1695
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• 2010

Pantothenate kinase (PanK) catalyzes the first step in the biosynthesis of the essential and ubiquitous cofactor coenzyme A (CoA) in all organisms. Here, we report the identification, cloning, and characterization of panK-sp from Streptomyces peucetius ATCC 27952. The gene encoded a protein of 332 amino acids with a calculated molecular mass of 36.8 kDa and high homology with PanK from S. avermitilis and S. coelicolor A3(2). To elucidate the putative function of PanK-sp, it was cloned into pET32a(+) to construct pPKSP32, and the PanK-sp was then expressed in E. coli BL21(DE3) as a His-tag fusion protein and purified by immobilized metal affinity chromatography. The enzyme assay of PanK-sp was carried out as a coupling assay. The gradual decrease in NADH concentration with time clearly indicated the phosphorylating activity of PanK-sp. Furthermore, the ca. 1.4-fold increase of DXR and the ca. 1.5-fold increase of actinorhodin by in vivo overexpression of panK-sp, constructed in pIBR25 under the control of a strong $ermE^*$ promoter, established its positive role in secondary metabolite production from S. peucetius and S. coelicolor, respectively.

• Korean Journal of Microbiology
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• v.23 no.2
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• pp.138-146
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• 1985

A Bacillus licheniformis ATCC31667 gene coding for a glucose isomerase has been cloned and expressed in glucose isomerase negative mutant of Escherichia coli. A recombinant plasmid, constructed by ligation of a EcoRI fragment of B.licheniformis chromosomal DNA to vector plasmid pBR322, was expressed glucose isomerase positive in E.coli LE392-6 with growth on minimal medium containing xylose as a sole carbon source. This recombinant plasmid, designated pBGI6, had the insery of 4.1Kb of Bacillus gene in EcoRI site, and restriction map of the plasmid was established. The plasmid pBG16 was very stable after 10days of serial transfer to a fresh medium. The activity of glucose isomerase from the transformed cell containing pBGI6 was increased about 20 fold than its wild type of host.

• Journal of Veterinary Clinics
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• v.16 no.2
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• pp.332-338
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• 1999

This study was carried out to investigate weight gain and prevention of diarrhea in suckling calves which were injected with recombinant bovine somatopropin (rBST). A total of 101 breeding cows were assigned to the six groups according to the administered dosage and injected time, respectively. Groups T-1, T-3, T-4 and T-6 were injected starting 1 week before calving and groups T-2 and T-5 were injected on the calving day. The six groups were injected five times at two week intervals. Groups T-1 and T-2 were injected with 250mg composite rBST, Group T-3 was injected with 375 mg composite rBST. Groups T-4 and T-5 were injected with 500mg composite rBST, And group T-6 was injected with 500mg rBST-S. The control group was not injected with BST. The groups injected with 500 mg BrST had a lower rate of morbidity from diarrhea than the control group or the groups injected with 250 mg rBST (T-1 and T-2). Weight gain was higher in group T-4 than in the control group or groups T-1 and T-2. In Korean Native Cattle, the total weight gain was greater in group T-4 than in the control group (p<0.05). In crossbred cows, total weight gain was the highest in group T-4, and the total weight gain rate was greater than in group T-4 and the control group (p<0.05). The results of the hematological values showed that injections of rBST did not affect the level of the RBC, TP and BUN in the breeding cows at 9 weeks after postpartum or the neonatal calves. The results of this study indicate that injecting breeding cows with 500 mg rBST before calving would be effective in the preventing of diarrhea and in increasing weight gain of calves from birth to weaning.

• The Journal of Korean Academy of Prosthodontics
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• v.44 no.3
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• pp.325-332
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• 2006

Statement of problem. Primary implant stability has long been identified as a prerequisite to achieve osseointegration. So the application of a simple, clinically applicable noninvasive test to assess implant stability and osseiointegratation are considered highly desirable. Purpose. The purpose of this study was to evaluate the ISQ value and the insertion torque of the 3 different implant system, then to evaluate whether there was a correlation between ISQ value and insertion torque; and to determine whether implant design has an influence on either insertion torque or ISQ value. Material and method. The experiment was composed of 3 groups: depending on the implant fixture design. Group1 was Branemark type parallel implant in $3.75{\times}7mm$. Group2 was Oneplant type straight implant in $4.3{\times}8.5mm$. Group3 was Oneplant type tapered implant in $4.3{\times}8.5mm$. Depending on the density of the bone, 2 types of bone were used in this experiment. Type I bone represented for cortical bone, type II bone represented for cancellous bone. With the insertion of the implant in type I and type II bone, the insertion torque was measured, then the ISQ value was evaluated, and then the correlation between insertion torque and ISQ value was analyzed Result and conclusion. Within the limitations of this study, the following conclusions were drawn. 1. Within the 3 different implants, the insertion torque value and ISQ value were higher in type I bone, when compared with type II bone.(p<0.05) 2. In type I and type II bone, Oneplant type tapered implant has the highest value in insertion torque.(p<0.05) 3. In type I and type II bone, there was no difference in ISQ values among the 3 types of implant. (p>0.05) 4. Significant linear correlation was found in $Br{\aa}nemark$ type parallel implant: $3.75{\times}7mm$ in type II bone.