• KSBB Journal
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• v.14 no.1
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• pp.58-65
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• 1999

A hydrogel, poly(N-isopropylacrylamide-co-N,N'-dimethylaminopropyl methacrylamide), sensitive to both pH and temperature was synthesized and characterized for its welling behavior, lower critical solution temperature (LCST), and its appearance. The hydrogel with 5 mol% of N,N'-diemthylaminopropyl methacrylamide (DMAPMAAm) increased its volume phenomenonally in a lower pH range (ph 1~8) even at temperature ($37^{\circ}C$ and $40^{\circ}C$) higher than LCST. This behavior was unique compared to the temperature -sensitive hydrogel which did not exhibit any swelling in the same pH range. The hydrogel with 20 mol% of DMAPMAAm was swollen significantly at a higher pH of 12. With pH decrease from 12 to 2 water content in the gel increased from 38.8 wt% and 60.6 wt%, and 90.8 wt% for 5 mol% and 20 mol% gel, respectively. The transition pH that pH effect overwhelmed temperature effect occurred at a lower pH for a higher temperature ($40^{\circ}C$) and a lower mol% (5 mol%) of DMAPMAAm. Transparency and LCST of the gel increased with higher DMAPMAAm mol%.

• Proceedings of the KIEE Conference
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• 1989.07a
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• pp.707-711
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• 1989

This system exchange half-duplex serial data at 1200 baud by FSK modulating a carrier frequency at 200KHz over the 110V A.C. power line. Transmitter output voltage to A.C. line is 4V p-p and line sensitivity is selected 2.54mV because CISPR Noise limitation is $66dB{\mu}V$ at 150 ${\sim}$ 500KHz. The designed and realized system has abtained system margin of 58 dB and probability of error, Pe = $1.78{\times}10^{-7}$ was obtained

• Applied Biological Chemistry
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• v.33 no.4
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• pp.325-329
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• 1990

This study was undertaken to determine thermodynamic characteristics of B. subtilis p-4 and B. licheniformis p-5 proteases isolated from fermented anchovy paste. $K_m$ values of two proteases for casein as a substrate were 0.38mM in p-4 protease and 0.18mM in p-5 protease, respectively. Denaturation constants($K_D$) of p-4 and p-5 proteases were $12.2{\times}10^{-5}/sec\;and\;19.0{\times}10^{-5}/sec\;at\;40^{\circ}C,\;and\;35.7{\times}10^{-5}/sec\;and\;46.3{\times}10^{-5}/sec\;at\;50^{\circ}C$, respectively. Activation energies($E_a$) of p-4 and p-S pmteases were 19.6 Kcal/mole and 15.2kcal/mole, respectively. Free energy of activation(${\Delta}G^*$), activation enthalpy(${\Delta}H^*$) and activation entropy(${\Delta}S^*$) at $40^{\circ}C$ were 23.21Kcal/mole, 18.98Kcal/mole and -13.50 eu, respectively for p-4 protease and 22.93Kcal/mo1e, 14.58Kcal/mole and -26.68 eu, respectively for p-5 protease. The major amino acids in p-4 protease(151 residues of amino acid) were Gly, Glu, Pro, Asp, Ser, Ala, Lys and Leu, while those in p-5 protease(247 residues of amino acid) were Gly, Glu, Asp, Ala and Leu. It may be concluded that heat denaturation of two proteases showed liner regression curve and p-5 protease was more sensitive to heat than p-4 protease.

• Food Science of Animal Resources
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• v.24 no.1
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• pp.97-102
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• 2004

The objective of this study was to control Kimchi fermentation using pH sensitive bacteriocin entrapping liposome(bacteriocin-liposome). The liposomes were prepared by the reverse-phase evaporation method from a mixture of DPPC(dipalmitoyl phosphatidylcholine, DPPE(dipalmitoyl phosphatidylethanolamine), DOPC(dioleoyl phosphatidylcholine) and cholesterol in a molar ration of 4:2:1:4. The bacteriocin-liposome was disruptured at pH 4 of buffer and was stable at alkaline pHs(6 and 7). Irrespective of the addition of the bacteriocin-liposomes, the pH of every Kimchi sample decreased to 5 during 5 days storage at 5$^{\circ}C$. Kimchi samples treated with bacteriocin-liposomes maintained pH 4 or higher, while Kimchi samples not treated with bacteriocin-liposomes exhibited pH 3.58 or lower. In general, the pH of Kimchi samples stored at 20$^{\circ}C$ decreased faster, compared to that of Kimchi samples stored at 5$^{\circ}C$. The pH of Kimchi samples treated with the bacteriocin-liposomes was 3.9 during 90 days storage, while that of the samples not treated with the bacteriocin-liposomes was 3.68 and 3.32 during 30 days and 90 days storages, respectively. Lactic acid bacteria in Kimchi treated with the bacteriocin-liposome grew relatively slow at 5$^{\circ}C$. The viable cell number of lactic acid bacteria increased up to 4${\times}$10$\^$7/ cells/ml and then decreased to 8${\times}$10$\^$6/ cells/ml during 90 days storage at 5$^{\circ}C$.

• Asian Journal of Turfgrass Science
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• v.12 no.1
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• pp.17-22
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• 1998

This experiment was conducted to investigate the active composting process with wastes from agricultural products. This was decomposed by active composting process for 28 days. Temperature of active airation period was maintained at 60~68C˚ for 6 days, and then 55˚C ~40˚C for 11 days. After turnover, composting temperture raised to 55~58˚C for 5 days and was maintained at air temperature condition from 6 days. Add then, compost was stabilized in the non-aerated depository for 2 months. The C/N ratios of these compests were 18.5,19.7 and 18.5 on the depths which were 5 cm, 10 cm and 20 cm, respectively. The pH of compest was changed from 6.5 to 7.2. Key words: Agricultural products, Wastes, C /N ratios.

• Elastomers and Composites
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• v.34 no.1
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• pp.3-10
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• 1999

Kinetics of solution photopolymerization of acrylonitrile(AN) with sensitizer, such as $NaSCN,\;KSCN,\;Ba(SCN)_2,\;NH_4SCN,\;ZnCl_2$ and $Na_2SeO_3$, were studied using UV crosslinker at various monomer concentrations($1.8{\sim}7.58mo1/1$), sensitizer concentrations($10{\sim}60%$), reaction temperature($10{\sim}70^{\circ}C$), energy intensities($1,000{\sim}9,900{\mu}J/cm^2$) at isothermal condition under nitrogen atmosphere. Under the irradiation of high pressure mercury lamp(${\lambda}=365nm$). High conversion and uniform molecular weight were obtained compare to thermal polymerization at reaction temperature of $50^{\circ}C$, reaction time of 3hr and 50% NaSCN without any initiator. Their kinetic model was as follows : $R_p=0.0142[M]^{0.82}[I]^{0.49}[S]^{0.52}$ exp(-1.33/RT).

• Korean Journal of Environment and Ecology
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• v.37 no.5
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• pp.347-366
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• 2023

In the present study, the vegetation was classified using the phytosociological method and canonical-correlation analysis (CCA) was implemented to analyze correlation between community structure and environmental factors in the natural habitats of forest byproducts, especially medicinal plants, such as Cudrania tricuspidata, Sorbus commixta, and Hovenia dulcis, in 2021-2022 to provide primary ecological data to establish environmental conditions for wild vegetable cultivation. A total of 11 plots in five regions, 8 plots in three regions, and 17 plots in 5 regions were selected for the natural habitats of C. tricuspidata in southern Korea, S. commixta in high mountains, and H. dulcis in valleys of central Korea, respectively. The importance value in each community was respectively analyzed as follows, in C. tricuspidata community, the importance value of C. tricuspidata (61.10) was the highest, followed by Celtis sinensis, Pinus thunbergii, Neolitsea aciculata, Styrax japonica, Carpinus coreana, Quercus serrata, and Q. acutissima. In Sorbus commixta community, Q. mongolica (57.21) was the highest, followed by, S. commixta (42.58), Betula ermani, Tilia amurensis, A. pseudosieboldianum, A. tschonoskii var. rubripes, Cornus controversa, Magnolia sieboldii, and Taxus cuspidata. In H. dulcis community, H. dulcis (64.58) was the highest, followed by Zelkova serrata, Cornus controversa, A. mono, Q. serrata, C. cordata, and Juglans mandshurica. As the result of the analysis on DBH of the major species having the high importance value, in C. tricuspidata community, C. tricuspidata, C. sinensis, Neolitsea aciculata, and C. coreana show the density of normal distribution, so the dominant status of these species is likely to continue. In S. commixta community, S. commixta show the density of reverse J-shaped curve, so the dominant status of these species is likely to be stable, and Q. mongolica, B. ermani and T. amurensis, show the density of normal distribution, so the dominant status of these species is likely to continue. In H. dulcis community, C. cordata, and J. mandshurica show the density of reverse J-shaped curve, so the dominant status of these species is likely to be stable, and H. dulcis, Z. serrata, C. controversa and A. mono had a formality distribution, suggesting a continuous domination of these species over the other species for the time being. The results of CCA ordination analysis using 11 environmental factors and 30 communities of three taxa classified by TWINSPAN analysis revealed that the altitude showed the strongest correlation with the vegetation. C. tricuspidata community was distributed on the moderate and gentle northeastern slope at low altitude with the highest pH, C.E.C, Ca²⁺, and Mg² and various P₂O₅, whereas S. commixta community was distributed on the steep slope at high altitude with the highest O.M and T-N and lower P₂O₅, Ca²⁺, Mg²⁺, C.E.C and pH, which is the opposite tendency of the environment of C. tricuspidata community. H. dulcis community was distributed on the gentle northern slope at lower altitude with an average pH, O.M, T-N, Ca²⁺, Mg²⁺, and C.E.C, except higher P₂O₅.

• The Journal of Natural Sciences
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• v.7
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• pp.53-58
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• 1995

To elucidate the effect of egg white lysozyme from Ogol fowl on the preservation of milks, fishcurd and sausage, changes of pH, volatile base nitrogen content and viable cell count were investigated during the storage periods at $20^{\circ}C$, $30^{\circ}C$ and $37^{\circ}C$ after the addition of lysozyme in each foods. Volatile base nitrogen count of raw milk as marker of spoilage was lowest(63 mg%) in 0.05% lysozyme addition lot which was stored at $20^{\circ}C$ for 2 days, and its preservation effect by lysozyme at $30^{\circ}C$ was enhanced with addition of glycine(0.1%). Preservation effect by lysozyme in commercial milk at $37^{\circ}C$ and in fishcurd at $5^{\circ}C$ and $20^{\circ}C$ were also good, and when sausage was stored at $5^{\circ}C$ after treatment of lysozyme instead of sorbic acid, its preservation effect was acceptable.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.1817-1820
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• 2015

Background: Hemoglobin A1c(HgA1c) is a marker of poor gylcemic control and elevation HgA1c is associated with increased risk of many cancers. We aimed to determine the HgA1c levels in endometrial cancer cases and any relationship with stage and grade of disease. Materials and Methods: A retrospective data review was performed between June 2011 and October 2012 at a tertiary referral center in Turkey. The study included 35 surgically staged endometrial cancer patients and 40 healthy controls. Preoperative HgA1c levels drawn within 3 months before surgery were compared. Also the relationships between HgA1c levels and stage, grade and hystologic type of cancer cases were evaluated. Results: The mean HgA1c levels were statistically significantly higher at $6.19{\pm}1.44$ in endometrial cancer cases than the $5.61{\pm}0.58$ in controls (p=0.027). With endometrial cancer cases, the mean HgA1c level was found to be $6.62{\pm}1.40$ for stage I and $6.88{\pm}1.15$ for stages II-IV (p=0.07). The figures were $6.74{\pm}1.65$ for endometrioid and $6.63{\pm}1.41$ for non-endometrioid type tumors (p=0.56). Mean HgA1c levels of $6.72{\pm}1.14$ for grade 1 and $6.62{\pm}1.42$ for grade 2-3 were observed (p=0.57). Conclusions: HgA1c levels in endometrial cancer patients were statistically higher than healthy controls. However, HgA1c did not show any significant correlation with stage, grade and histologic type in endometrial cancer cases.

• Journal of Embryo Transfer
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• v.28 no.2
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• pp.121-125
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• 2013

This study was carried out to investigate the general characteristics of semen such as semen volume, pH, sperm motility and sperm concentration of the semen collected from Shih Tzu dogs (age of 24 to 48 months, weight of 4 to 8 kg) by using the method of digital manipulation of the penis. The effect of preservation temperature and time on motility of fresh semen was also investigated in the present study. Semen was collected for 16 times from 4 male Shih Tzu dogs by multiple ejaculations (four times ejaculation per dog). The average of semen volume, semen pH, sperm motility and sperm concentration of the second fraction containing small volume of the initial third fraction per ejaculation were $2.11{\pm}0.31$ ml, $6.25{\pm}0.07$, $97.59{\pm}1.03%$ and $2.05{\pm}0.14{\times}10^8$ cells/ml, respectively. Average semen volume per ejaculate, semen pH, sperm motility and sperm concentration of the first fraction from the ejaculation were $1.12{\pm}0.15$ ml, $5.99{\pm}0.14$, $16.09{\pm}6.18%$ and $5.16{\pm}2.03{\times}10^5$ cells/ml, respectively. Those of second fraction were $2.07{\pm}0.29$ ml, $6.36{\pm}0.13$, $97.31{\pm}1.36%$ and $2.15{\pm}0.30{\times}10^8$ cells/ml, respectively. Those of third fraction were $2.60{\pm}0.29$ ml, $6.63{\pm}0.08$, $95.72{\pm}1.61%$ and $6.03{\pm}1.83{\times}10^7$ cells/ml, respectively. Sperm motility was significantly higher at $17^{\circ}C$ preservation temperature than at $5^{\circ}C$ or $36^{\circ}C$ during preservation period except 1 h preservation (P<0.05). When preservation temperature was $17^{\circ}C$, sperm motility was $96.69{\pm}1.49%$ at 1 h, $91.38{\pm}1.90%$ at 6 h, $88.38{\pm}2.34%$ at 12 h, $78.13{\pm}4.58%$ at 18 h, $58.44{\pm}8.57%$ at 24 h and $29.56{\pm}5.06%$ at 30 h, respectively.