• The Korean Journal of Mycology
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• 제14권3호
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• pp.225-229
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• 1986

Cellulosic substance which plays an important role in carbon cycle is most abundant in the nature world. Some higher fungi are able to digest cellulose directly to satisfy their carbohydrate requirement. Then, in order to investigate the enzymatic components of Lenzites betulina (Fr.) being wood rot, that fungus was collected in Kwangneung area. The carpophore of the fungus was smashed with cool distilled water, extracted and salted out by ammonium sulfate. And then the precipitate was purified by dialysing with visking tube and dissolved with pH 7.8 ammonia water, and the extract was filtrated. The fraction of filtrate was obtained as light brown powder after lyophilization, and determined cellulolytic activity. Cellulolytic potency of Lenzites betulina (Fr.) was 1. 65 unit/ml. The cellulase of Lenzites betulina (Fr.) was stable at below $45^{\circ}C$ and range of pH $4.5{\sim}6.0$ and is completely inactivated at $60^{\circ}C$ for 15 minutes. The optimum condition for the enzymatic reaction was $40^{\circ}C$ and pH 4.0. The enzyme activity was not influenced by the presence of $Ca^{2+}$ and $Fe^{2+}$.

• The Korean Journal of Community Living Science
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• 제20권3호
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• pp.449-460
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• 2009

This study was performed to investigate gruel intake, preference and opinions about gruel development to produce new products for breakfast. The subjects of this study were 307 adults in Chungju city. People who favored gruels were 212(69.5%) and 50.2% of the subjects liked the gruel because of good digestion and absorption. They liked midium thick or thin gruel and also liked grain granules with some stuff as contents. The gruels often taken were abalone gruel(45.9%), pumpkin gruel(41.7%), chicken gruel(34.9%), vegetable gruel(33.6%), beef and mushroom gruel(30.3%) etc. in order. The frequency of gruel intake was 1-2 times/year and 59.6% of subjects got gruels from the special gruel restaurant. People who need gruels most were patients, indigestible person, the elderly, weaning babies, workers and students missing breakfast in order. Sesame taste obtained the highest score of all, that of bitter taste was significantly higher in over fifty year old people (p<0.05), and hot taste score was significantly higher in 30-40 year old people (p<0.01). The gruels preferred most were abalone gruel, pumpkin gruel, chicken gruel, beef and mushroom gruel, vegetable gruel, red bean gruel, pine nut gruel, egg gruel, sesame gruel, plain grain gruel etc. in order. Fifty seven percent of subjects wanted to develope new gruels fortified nutrients. In conclusion, when the substitute gruel for breakfast is developed, it is better to use food materials to be easy to digest, to have grain granules with some stuff inside and to be sesame taste.

• The Korean Journal of Mycology
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• 제15권3호
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• pp.169-174
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• 1987

The studies on the screening and properties of Raw Starch Saccharifying Microorganism were as follows;Apotent mold strain was selected and screened to digest raw starch, which was classified as a strain of Aspergillus sp. SN-871. The crude enzyme production was maximized when grown on wheat bran media for 5 days at $30^{\circ}C$ and pH 4.0. The stable range of pH was 2 to 5.

• Journal of Microbiology and Biotechnology
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• 제15권2호
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• pp.239-246
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• 2005

Some characteristics of two forms of glucoamylase (glucan 1 A-$\alpha$-glucosidase, EC 3. 2. I. 3) purified from Aspergillus coreanus NR 15-1 were investigated. The enzymes were produced on a solid, uncooked wheat bran medium of A. coreanus NR 15-1 isolated from traditional Korean Nuruk. Two forms of glucoamylase, GA-I and GA-II, were purified to homogenity after 5.8-fold and 9.6-fold purification, respectively, judged by disc- and SDS-polyacrylamide gel electrophoresis. The molecular mass of GA-I and GA-II were estimated to be 62 kDa and 90 kDa by Sephadex G-1OO gel filtration, and 64 kDa and 91 kDa by SDS-polyacrylarnide gel electrophoresis, respectively. The optimum temperatures of GA-I and GA-II were 60$^circ$C and 65$^circ$C, respectively, and the optimum pH was 4.0. The activation energy (Ea value) of GA-I and GA-II was 11.66 kcal/mol and 12.09 kcal/mol, respectively, and the apparent Michaelis constants (K_{m}) of GA-I and GA-II for soluble starch were found to be 3.57 mg/ml and 6.25 mg/ml, respectively. Both enzymes were activated by 1 mM Mn^{2+} and Cu^{2+}, but were completely inhibited by 1 mM N­bromosuccinimide. The GA-II was weakly inhibited by 1 mM p-CMB, dithiothreitol, EDTA, and pyridoxal 5-phosphate, but GA-I was not inhibited by those compounds. Both enzymes had significant ability to digest raw wheat starch and raw rice starch, and hydrolysis rates of raw wheat starch by GA-I and GA-II were 7.8- and 7.3-fold higher than with soluble starch, respectively.

• Development and Reproduction
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• 제3권1호
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• pp.69-74
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• 1999

Insulin-like growth factors (IGF-1 and IGF-2) play an important regulatory role in premplantation embryonic development. To study the role of IGF-1 during premplantation embryonic development in mouse, the presence of mRNA transcripts for IGF-1 and IGF-lR in the oocytes and preimplantation embryos was examined. In this study, the transcripts of IGF-1 was detected in oocytes using primers for IGF-1. The PCR products were identified by Msp I restriction enzyme digest. We revealed that the transcripts of IGF-1 and IGF-1R were presented in the oocytes and preimplantation embryos. The highest mRNA levels in GV stage oocytes were decreased at 4- or 8-cell stage and then reincreased upto blastocyst. The presence of IGF-1 and IGF-lR in GV-oocytes suggests that the transcripts in the early stage embryos were derived from maternal genome. Additionally, the presence of IGF-1 and IGF-lR in the oocytes and preimplantation embryos suggests that IGF-1 plays an autocrine role during preimplantation embryonic development through IGF-lR as a signalling pathway.

• Korean Journal of Animal Reproduction
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• 제27권2호
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• pp.97-102
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• 2003

This study was carried out to find out PSS(Porcine Stress Syndrome) with the PSE(Pale, Soft, Exudative) in different piglets. These experiments were accomplished with the aid of PCR-RFLP(Polymerase Chain Reaction-Restriction Fragment Length Polymorphism). The samples were collected and examined from umbilical cord blood of piglets of Yorkshire, Landrace and Crossbred. And then, the PCR products were digested by restriction enzyme, Hha I. The results obtained were as follows; The PCR products of the blood genomic DNA of ryanodine receptor gene were length of 1 .8kb in umbilical cord blood. Normal type(NN), heterozygous type(Nn) and recessively homozygous type(nn, PSS) as a result of digestion of restriction enzyme, Hha 1, were 90.0%, 10.0% and 0.0% in Yorkshire piglets, 76.2%, 19.0% and 4.8% in Landrace, 69.1%, 23.8% and 7.1% in crossbred, respectively. As already showing the above results, the blood from piglets umbilical cord can be availably used for the determination of genotypes of PSS because of easiness of blood collection without stress in live piglets.

• Journal of Internet Computing and Services
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• 제7권6호
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• pp.157-174
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• 2006

Ajax interaction model changes the posture of web application to become a stateful over HTTP. Ajax applications are long-lived inthe browser. XMLHTTPRequest (XHR) is used to facilitate the data exchange. Using HTTPS over this interaction is not viable because of the frequency of data exchange. Moreover, switching of protocols form HTTP to HTTPS for sensitive information is prohibited because of server-of-origin policy. The longevity, constraint, and asynchronous features of Ajax application need to hove a different authentication and session fondling mechanism that invoke re-authentication. This paper presents an authentication and session management scheme using Ajax. The scheme is design lo invoke periodic and event based re-authentication in the background using digest authentication with auto-generated password similar to OTP (One Time Password). The authentication and session management are wrapped into a framework called AWASec (Ajax Web Application Security) for coupling to avoid broken authentication and session management.

• The Journal of the Korea Contents Association
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• 제12권2호
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• pp.69-77
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• 2012

In the case of the password-based PKI technology, because it protects by using the password which is easy that user memorizes the private key, he has the problem about the password exposure. In addition, in the system of electronic bidding, the illegal use using the authentic certificate of the others increases. Recently, in order to solve this problem, the research about the PKI technology using the biometrics is actively progressed. If the bio information which the user inputs for the bio authentication is converted to the template, the digest access authentication in which the security is strengthened than the existing authentication technology can be built. Therefore, in this paper, we had designed and developed the system of electronic bidding which it uses the most widely used fingerprint information in the biometrics, it stores the user fingerprint information and certificate in the fingerprint security token and can authenticate the user. In case of using the system of electronic bidding of the public key infrastructure using the fingerprint information proposed in this paper the agent bid problem that it uses the certificate of the others in not only user authentication intensification but also system of electronic bidding can be concluded.

• Journal of the Korea Organic Resources Recycling Association
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• 제22권2호
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• pp.57-66
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• 2014

The leachate recirculation anaerobic digestion system has the advantage of stable methane gas generation compared with existing one phase systems. In this study, an anaerobic digestion system fed with source separated food waste from school cafeteria was studied with different food waste/inoculum anaerobic sludge volume ratios (8:2, 3:7, 2:8). From this study, leachate recirculation anaerobic reactor with food waste/inoculum anaerobic sludge volume ratio of 2:8 that is 9 gVS/L of OLR(Organic Loading Rate) had the highest gas production. Also this anaerobic reactor showed daily decrease of H2S and NH3 contents in produced gas. Average biogas yield was 1.395 m3 Biogas/kg VS added. Other anaerobic reactors with food waste/inoculum anaerobic sludge volume ratio of 8:2 and 3:7 stopped methane gas production.

• Journal of Korean Society for Atmospheric Environment
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• 제21권4호
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• pp.423-430
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• 2005

This study was investigated with sample digestion techniques and a reliability of the analytical results for a quantitative analysis of a standard reference material ('urban particulate matter', SRM 1648). The metallic elements were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) with closed vessel microwave acid digestion method and atomic absorption spectroscopy (AAS). Quality control of the overall analytical procedures for metallic element determinations of standard reference material were estimated by analysis of a SRM 1648. Three digestion solutions $(type\;1:\;HNO_3,\;type\;2:\;HNO_3\;and\;H2O_2(4'1)\;mixture,\;type\;3:5.55\%\; HNO_3\;and\;16.75\%\;HCI\;mixture)$ were applied to SRM 1648. As a result, three digestion solutions used in this study are completely unable to digest Cr of SRM 1648. Reliability of Cr and As showed some errors in the digestion with digestion solution type (3) due to the influence of chlorides. Type (3) digestion solutions are sufficient to fulfill the digestion of As as well as Se in SRM 1648. ICP-MS results showed the improvement in accurate and precise determination of some trace elements like Cd, V and Pb in SRM 1648. It is important to use the proper digestion solution for each element to qualify analytical precision.