• KSBB Journal
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• 제13권3호
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• pp.308-311
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• 1998

A novel process was developed to simultaneously produce invertase and yeast extract from baker's yeast using ultrafiltration (UF) and microfiltration (MF) membrane processing. After the extraction of invertase under the optimal condition obtained in this study, invertase was separated from yeast cells using a hollow fiber membrane with a pore size of 0.1 $\mu\textrm{m}$. The resulting permeate containing invertase was concentrated using a hollow fiber membrane with a nominal molecular weight cut-off of 30 kDa. The yeast cell and permeate solutions, which were obtained after MF and UF membrane processing, respectively, were mixed together, and the autolysis was performed at 50$^{\circ}C$ in the presence of 5% (w/v) ethanol and 1% (w/v) NaCl. As a result, the yeast extract and invertase could be simultaneously produced from baker's yeast by this novel process.

• 한국환경과학회지
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• 제8권2호
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• pp.165-169
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• 1999

The incidence of aseptic meningitis infection is ensuing and threatening the health of children. Enteroviruses are the major agents of aseptic meningitis and identification of virus has been a clue to diagnosis and epidemiology. The outbreak of aseptic meningitis occurred in Pusan, 1998. Patients were concentrated from April through November. Children were more susceptible than adults. Among 306 cases of specimens from stool, throat swab tested, only 7.2% were positive on virus isolation, 12 cases from stool and 10 from throat, respectively. All isolated 7 serotypes of viruses represented cytopathic effect on cultured cells. Three types of echovirus 6.25, 30 and coxsackievirus B2, B3, B4, B6 were identified by neutralizing antibody test. Isolated coxsackievirus and echovirus were observed by an electron microscope with negative staining.

• 대한핵의학회:학술대회논문집
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• 대한핵의학회 2001년도 제40차 춘계학술대회 및 연수교육
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• pp.4-10
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• 2001

The radionuclide therapy is a protocol for tumor control by administering radionuclides as the cytotoxic agents. Radionuclides concentrated at the site of cancerous lesion are expected to kill the cancerous cells with minimal injury to the normal tissue. The efficacy of every radionuclide treatment can be evaluated by examining the toxicity to the lesion differentiated from that to the normal tissue. Radiation dosimetry is the procedure of quantitating the energy absorbed by target volumes of interest. Dosimetric information plays an indicator of the expected radiation damage and thus the therapeutic efficacy. This paper summarizes the dosimetric aspects in radionuclide therapy in terms of radionuclides of use, radiation dosimetry methodology and considerations for each treatment in practical use.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2005년도 국제학술대회
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• pp.359-364
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• 2005

The possible use of milk factory waste water as fermentation media for the production of citric acid by cells of Aspergillus niger ATCC 9142 has been investigated. The addition of $Mn^{2+}$, $Fe^{2+}$ and $Cu^{2+}$ to a medium promoted the citric acid production steadily, but addition of another metal ion $Mg^{2+}$decreased the citric acid production. The concentrations of citric acid were marked up to 7.2g/1 and 16.5g/l in a batch bioreactor by A. niger ATCC 9142 with 50g/1 and 100g/l of reducing sugar concentration in milk factory waste water, respectively.

• 한국임상수의학회지
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• 제3권1호
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• pp.277-298
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• 1986

This paper reviews the mechanisms effecting host defense in the mammary gland and assesses their possible in preventing of bovine mastitis. The streak canal is the first line of defense against invading mastitis pathogens, providing a physical barrier and antibacterial substances. The milk leukocytes are a second defense line by ingesting pathogens breached the streak canal by multiplication, physical passage, and propulsion during milking. Leukocytosis in milk and enhancement of the phagocytic defense machanisms of the udder were accomplished by inserting intramammary devices. Milk antibodies serum derived and synthesized in mamma tissue aggregate and opsonise bacteria, agglutinate and neutralise toxins, and inhibit. binding of bacteria to epitherial surfaces. Vaccination generally has been unsuccessful because protection is not absolute, but immunization is useful in controlling specific pathogens. Immunostimulant to enhance locally the protective nature of antibody-producing plasma cells concentrated in internal teat end tissue may be effective in reducing the occurrence of infection, but ineffective in preventing intramammary infections.

• Transactions on Electrical and Electronic Materials
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• 제8권2호
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• pp.97-102
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• 2007

The charging/discharging characteristics of electric double layer capacitors (EDLCs) for an electric power storage device application were investigated. The specific area of the carbonaceous electrode surface by the BET method was in the range of $1800{\sim}2000\;m^2/g$. The charge distributions during charging and discharging were measured by means of a pulsed-electro-acoustic (PEA) method, and the voltage characteristics of EDLCs connected to solar cells were evaluated. The results showed that the distributions of positive and negative charges were spatially uneven, which was due to the mobility of the positive and negative charges in the carbonaceous electrode surface of the EDLCs. The charge accumulation region concentrated on central part of the carbonaceous electrode and the required times for charging and discharging were almost same.

• Animal cells and systems
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• 제7권3호
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• pp.191-196
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• 2003

Taxonomic confusion has been presented within freshwater crayfishes of the genus Cambaroides since Starobogatov published morphological definition and revision of the group in 1995. He suggested that Cambaroides should be revised: the C. dauricus, contained three species C. dauricus, C. wladiwostokiensis, and C. koshewnikowi; the C. schrenckii with two. species C. schrenckii and C. sachalinensis. Also Straovogatov did not take into account the previous data. of crayfish distributions. In order to. clear up the confusion, the taxonomy of crayfish sampled from Mongolia, Russia, China, and North Korea was reassessed. Starovogatov's key could not lead to the correct identification. Also, detailed observations of apical robe of the male first pleopod did not support the taxonomy on the genus Cambaroides proposed by Starobogatov in 1995. However, some local variations of morphology exist in rostrum, pleuron, and telson of Asian crayfish. Future studies should be concentrated on whether there are geographical clines of morphology or if taxonomic subdivision is necessary.

• Molecules and Cells
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• 제20권2호
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• pp.256-262
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• 2005

The neuronal cytoskeleton is essential for establishment of neuronal polarity, but mechanisms controlling generation of polarity in the cytoskeleton are poorly understood. The nonreceptor tyrosine kinase, Fer, has been shown to bind to microtubules and to interact with several actin-regulatory proteins. Furthermore, Fer binds p120 catenin and has been shown to regulate cadherin function by modulating cadherin-${\beta}$-catenin interaction. Here we show involvement of Fer in neuronal polarization and neurite development. Fer is concentrated in growth cones together with cadherin, ${\beta}$-catenin, and cortactin in stage 2 hippocampal neurons. Inhibition of Fer-p120 catenin interaction with a cell-permeable inhibitory peptide (FerP) increases neurite branching. In addition, the peptide significantly delays conversion of one of several dendrites into an axon in early stage hippocampal neurons. FerP-treated growth cones also exhibit modified localization of the microtubule and actin cytoskeleton. Together, this indicates that the Fer-p120 interaction is required for normal neuronal polarization and neurite development.

• Journal of Power Electronics
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• 제16권6호
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• pp.2067-2075
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• 2016

Cascaded H-bridge multilevel inverters are currently used because it enables the integration of various sources, such as batteries, ultracapacitors, photovoltaic array and fuel cells in a single system. Conventional modulation schemes for multilevel inverters have concentrated mainly on the generation of a low harmonic output voltage, which results in less effective utilization of connected sources. Less effective utilization leads to a difference in the charging/discharging of sources, causing unsteady voltages over a long period of operation and a reduction in the lifetime of the sources. Hence, a charge balance control scheme has to be incorporated along with the modulation scheme to overcome these issues. In this paper, a new approach for charge balancing in symmetric cascaded H-bridge multilevel inverter that enables almost 100% charge balancing of sources is presented. The proposed method achieves charge balancing without any additional stages or complex circuit or considerable computational requirement. The validity of the proposed method is verified through simulation and experiments.

• 약학회지
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• 제27권4호
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• pp.309-314
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• 1983

Six hydantoin derivatives, 3-(2-chloroethyl) hydantoin (6a), 3-(2-chloroethyl)-5-isopropylhydantoin (6b), 3-(2-chloroethyl)-5-isobutylhydantoin (6c), 3-(2-chloroetbyl)5-(2-butyl) hydantoin (6d), 3-(2-chloroethyl)-5-benzylhydantoin (6e), 3-(2-chloroethyl)-5-(indolyl-3-methyl) hydantoin (6f), were prepared by the treatment of the corresponding salt of amino acids with 2-chloroethyl isocyanate in cold water, followed by refluxing in concentrated HCl solution. Anticancer activity of the synthesized hydantoin derivatives were examined on murine leukemia L1210 cells growing in Fischer medium. Among them, 3-(2-chloroethy)-5-isobutyl-hydantoin (6c) showed substantially low $ED_{50}$ value of $9.6{\mu}g/ml$.