• Journal of Microbiology
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• v.38 no.4
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• pp.245-249
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• 2000

Catabolic pathways for the degradation of various aromatics by Sphingomonas yanoikuyae Bl are intertwined, joining at the level of substituted benzoates, which are further degraded vita ring cleavage reactions. The mutant strain EK497, which was constructed by deleting a large DNA region containing most of the genes for biphenyl, naphthalene, m-xylene, and m-toluate degradation, was unable to grow on all of the aromatics tested except for benzoate as the sole source of carbon and energy.S. yanoikuyae EK497 was found to possess only catechol ortho-ring cleavage activity due to deletion of the genes for the meta-cleavage pathway. Wild-type S. yanoikuyae Bl grown on benzoate has both catechol orthoand meta-cleavage activity. However, m-xylene and m-toluate, which are metabolized through methylbenzoate, and biphenyl, which is metabolized through benzoate, induce only the meta-cleavage pathway, suggesting the presence of a substrate-dependent induction mechanism.

• Elastomers and Composites
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• v.40 no.4
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• pp.242-248
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• 2005

To study the fatigue properties of three type of foams for footwear midsole, polyurethane(PU), phylon(PH) and injection phylon(IP) foams were prepared with different hardnesses. Three types of foams were repetitively compressed for 50,000 cycles at 50 rpm. Cell shapes of foams were deformed with repetitive compression. The extent of cell deformation of IP was larger than those of PH and PU. Permanent strain of foam was made by repetitively compressing the foam, and the extent of IP was larger than those of PU and PH. Maximum compression forces of three types of the foams were decreased with the repetitive compression, and IP had the largest decrease in compression load of foam with compression. Decreases in maximum compression force of three types of foams were increased with increase of the hardness of foam.

• Journal of Microbiology and Biotechnology
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• v.30 no.12
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• pp.1944-1949
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• 2020

Mutant sugar transporter ScGAL2-N376F was overexpressed in Kluyveromyces marxianus for efficient utilization of xylose, which is one of the main components of cellulosic biomass. K. marxianus ScGal2_N376F, the ScGAL2-N376F-overexpressing strain, exhibited 47.04 g/l of xylose consumption and 26.55 g/l of xylitol production, as compared to the parental strain (24.68 g/l and 7.03 g/l, respectively) when xylose was used as the sole carbon source. When a mixture of glucose and xylose was used as the carbon source, xylose consumption and xylitol production rates were improved by 195% and 360%, respectively, by K. marxianus ScGal2_N376F. Moreover, the glucose consumption rate was improved by 27% as compared to that in the parental strain. Overexpression of both wild-type ScGAL2 and mutant ScGAL2-N376F showed 48% and 52% enhanced sugar consumption and ethanol production rates, respectively, when a mixture of glucose and galactose was used as the carbon source, which is the main component of marine biomass. As shown in this study, ScGAL2-N376F overexpression can be applied for the efficient production of biofuels or biochemicals from cellulosic or marine biomass.

• Journal of Veterinary Clinics
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• v.40 no.3
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• pp.203-208
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• 2023

A 13-year-old neutered male mixed-breed dog presented with generalized lymphadenopathy and erythematous cutaneous lesions in the ear pinnae. Fine-needle aspiration cytology of the lymph nodes revealed small to intermediate lymphocytes with a "hand mirror" configuration as the predominant cell type. Histopathological analysis of the lymph node showed an infiltrate of CD3-positive small lymphocytes compressing the follicles against the capsule owing to neoplastic cell expansion. Flow cytometric analysis revealed a homogeneous population of CD3+/CD4-/CD5+/CD8-/CD21+/CD34-/CD45- cells in both the peripheral blood and aspirated lymph nodes, which supports the diagnosis of T-zone lymphoma. Laboratory tests revealed lymphocytosis (14,144 cells/µL) in the peripheral blood. However, contrary to expectations, the bone marrow examination revealed no evidence of lymphocytic infiltration. T-zone lymphoma is an indolent lymphoma with a long survival period, and knowledge of its characteristics may affect disease staging and prognosis evaluation. Therefore, peripheral blood count as a sole screening tool for bone marrow metastasis should be used with caution.

• Journal of Microbiology
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• v.44 no.6
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• pp.689-693
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• 2006

Pbh1, from the fission yeast Schizosaccharomyces pombe, is a baculoviral inhibitor of apoptosis (IAP) repeat (BIR) domain-containing protein. Its unique encoding gene was previously found to be regulated by nitric oxide and nitrogen starvation. In the current work, the Pbh1-lacZ fusion gene was used to elucidate the transcriptional regulation of the pbh1 gene under various carbon sources. When fermentable carbon sources, such as glucose (at a low concentration of 0.2 %), sucrose (2.0 %) and lactose (2.0 %), were the sole carbon source, the synthesis of $\beta$-galactosidase from the Pbh1-lacZ fusion gene was reasonably enhanced. However, the induction by these fermentable carbon sources was abolished in the Pap1-negative S. pombe cells, implying that this type of induction of the pbh1 gene is mediated by Pap1. Ethanol (2.0%), a nonfermentable carbon source, was also able to enhance the synthesis of $\beta$-galactosidase from the fusion gene in wild-type cells but not in Pap1-negative cells. The results indicate that the S. pombe pbh1 gene is up-regulated under metabolic oxidative stress in a Pap1-dependent manner.

• International Journal of Highway Engineering
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• v.18 no.6
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• pp.173-180
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• 2016

OBJECTIVES : Fixed roadside objects are a threat to drivers when their vehicles deviate from the road. Therefore, such roadside objects need to be suitably dealt with to decrease accidents. This study determines the factors affecting the severity of accidents because of fixed roadside objects. METHODS : This study analyzed the crash severity impact of fixed roadside objects by using ordered probit regression as the analysis methodology. In this research, data from 896 traffic accidents reported in the last three years were used. These accidents consisted of sole-car accidents, fixed roadside object accidents, and lane-departure accidents on the national highway of Korea. The accident severity was classified as light injury, severe injury, and death. The factors relating to the road and the driver were collected as independent variables. RESULTS : The result of the analysis showed that the variables of the crash severity impact are the collision location (left side), gender of the driver (female), alcohol use, collision facility (roadside trees, traffic signals, telephone poles), and type of road (rural segments). Additionally, the collision location (left side), gender of the driver (female), alcohol use, collision facility (street trees, traffic signals, telephone poles), and type of road (rural segments), in order of influence, were found to be the factors affecting the crash severity in accidents due to fixed roadside objects. CONCLUSIONS : An alternative solution is urgently required to reduce the crash severity in accidents due to fixed roadside objects. Such a solution can consider the appropriate places to install breakaway devices and energy-absorbing systems.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.26
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• pp.35-86
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• 2005

International distributorship contract(IDC), as well as international agency contract is a type of contract which is most frequently used in international trade. But one of the main difficulties faced by parties of IDC is the lack of uniform rules for this type of contract. This means that both parties should be careful about each clause of the contract when they draw up it. The ICC prepared model form which incorporates the prevailing practice in international trade, and which aims at protecting and balancing the legitimate interests of both parties. This author examined the several important clauses in this model contract. The purpose of this examination is to help the contracting parties for better understanding and applying them in their actual contracting practice, which based on this model contract. When the supplier and the distributor execute their contract or use ICC Model Contract, they should be careful about the following points: First, some terminologies(like, "territory", "product", "competing products" and "exclusivity") should be clearly defined in their contract. Second, regarding the supplier's functions including "supplying products" and the distributor's responsibility including "undertaking not to compete", and "attaining guaranteed minimum targets", both parties should make clear about each party's right and obligation as well as one party's remedies available when other party makes breach of its obligation. Third, both parties should examine the relationship between the "exclusivity" or "sole" and competition law which is regarded as a mandatory rule in the territory. Forth, when both parties lay down "termination clause" in the contract, they should make clear about the indemnity in case of termination. Fifth, as there is not uniform law for the distributorship contract, it is inevitable to choose any local law as an applicable law in case of litigation. So both parties should keep in mind to insert arbitration clause to avoid the application of the local law. Besides, both parties should consider their individual and specific circumstances and try to reflect them in their contract by Annex I to XI attached to the end of model contract.

• Journal of Microbiology and Biotechnology
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• v.16 no.1
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• pp.84-91
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• 2006

A Saccharomyces cerevisiae pgs1 nulI mutant, which is deficient with phosphatidyl glycerol (PG) and cardiolipin (CL) biosynthesis, grows well on most fermentable carbon sources, but fails to grow on non-fermentable carbon sources such as glycerol, ethanol, and lactate. This mutant also cannot grow on galactose medium as the sole carbon source. We found that the incorporation of $[^{14}C]-galactose$, which is the first step of the galactose metabolic pathway (Leloir pathway), into the pgs 1 null mutant cell was extremely repressed. Exogenously expressed PGS1 (YCpPGS1) under indigenous promoter could completely restore the pgs1 growth defect on non-fermentable carbon sources, and dramatically recovered $[^{14}C]-galactose$ incorporation into the pgs1 mutant cell. However, PGS1 expression under the GALl promoter $(YEpP_{GAL1}-PGS1myc)$ could not complement pgs1 mutation, and the GAL2-lacZ fusion gene $(YEpP_{GAL2}-lacZ)$ also did not exhibit its $\beta-galactosidase$ activity in the pgs1 mutant. In wild-type yeast, antimycin $A(1\;{\mu}g/ml)$, which inhibits mitochondrial complex III, severely repressed not only the expression of the GAL2-lacZ fusion gene, but also uptake of $[^{14}C]-galactose$. However, exogenously expressed PGS1 partially relieved these inhibitory effects of antimycin A in both the pgs1 mutant and wild-type yeast, although it could not basically restore the growth defect on galactose by antimycin A. These results suggest that the PGSI gene product has an important role in utilization of galactose by Gal genes, and that intact mitochondrial function with PGS1 should be required for galactose incorporation into the Leloir pathway. The PGS1 gene might provide a clue to resolve the historic issue about the incapability of galactose with deteriorated mitochondrial function.

• Microbiology and Biotechnology Letters
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• v.35 no.1
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• pp.52-57
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• 2007

A gas-circulating bioreactor was used for enrichment of autotrophic methanogens. Mixture of hydrogen and carbon dioxide (5:1) was used as a sole energy and carbon source. Anaerobic digestive sludge isolated from wastewater treatment system was inoculated into the gas-circulating bioreactor. The enrichment of two chemolithotrophic methanogens, Methanobacterium curvum and Methanobacterium oryzae was accomplished in the gas-circulating bioreactor. The enriched bacteria were cultivated in a bioreactor equipped with hollow-fiber hydrogen-supplying system (hollow-fiber bioreactor), and a hybrid-type bioreactor equipped with hollow-fiber hydrogen-supplying system and electrochemical redox control system. The methane productivity was maximally 30% (V/V) in the hollow-fiber bioreactors and 50% (V/V) in the hybrid-type bioreactor.

• Journal of Microbiology and Biotechnology
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• v.21 no.5
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• pp.483-493
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• 2011

An acid phosphatase (HppA) activated by $NH_4Cl$ was purified 192- and 34-fold from the periplasmic and membrane fractions of Helicobacter pylori, respectively. SDS-polyacrylamide gel electrophoresis revealed that HppA from the latter appears to be several kilodaltons larger in molecular mass than from the former by about 24 kDa. Under acidic conditions (pH${\leq}$4.5), the enzyme activity was entirely dependent on the presence of certain mono- and/or divalent metal cations (e.g., $K^+$,$ NH_4{^+}$, and/or $Ni^{2+}$). In particular, $Ni^{2+}$ appeared to lower the enzyme's $K_m$ for the substrates, without changing $V_{max}$. The purified enzyme showed differential specificity against nucleotide substrates with pH; for example, the enzyme hydrolyzed adenosine nucleotides more rapidly at pH 5.5 than at pH 6.0, and vice versa for CTP or TTP. Analyses of the enzyme's N-terminal sequence and of an $HppA^-$ H. pylori mutant revealed that the purified enzyme is identical to rHppA, a cloned H. pylori class C acid phosphatase, and shown to be the sole bacterial 5'-nucleotidase uniquely activated by $NH_4Cl$. In contrast to wild type, $HppA^-$ H. pylori cells grew more slowly. Strikingly, they imported $Mg^{2+}$ at a markedly lowered rate, but assimilated urea rapidly, with a subsequent increase in extracellular pH. Moreover, mutant cells were much more sensitive to extracellular potassium ions, as well as to metronidazole, omeprazole, or thiophenol, with considerably lowered MIC values, than wild-type cells. From these data, we suggest that the role of the acid phosphatase HppA in H. pylori may extend beyond 5'-nucleotidase function to include cation-flux as well as pH regulation on the cell envelope.