• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.4
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• pp.271-282
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• 1982

The browning development, mainly through the Maillard reaction, occurring in the dried fish meat products during storage causes reduction of the nutritional value due to the loss of the essential amino acid such as available lysine as well as off -flavor resulting in the deterioration of the food quality thus shortening the shelflife. In the work, the changes in the amount of available lysine, extractable nitrogenous compounds (nonprotein-N, amino-N, trimethylamine oxide, trimethylamine, and free lysine) and development of browning were measured to assess the relationship between the shelflife and the quality loss in dried filefish under the steady state conditions (35,45, and $55^{\circ}C;a_{w}'s$ of 0.44 0.52, 0.65 and 0.75 at each temperature) and fluctuating temperature condition of $35/55^{\circ}C$ will. alternating 7 day periods at each water activity. The results indicated that the amount of available lysine and extractable nitrogenous compounds except TMA decreased rapidly with increasing temperatures and water activities while the rate of available lysine and extractable nitrogenous compounds must be involved in the initial stage of brown pigment formation. The available lysine loss of the dried filefish products stored under the fluctuating temperature conditions was greater than that stored under its fixed mean temperature, $45^{\circ}C$. The activation energies for lysine loss obtained from the Arrhenius plot ranged 6.9 to 4.4 Kcal/mol and $Q_{10}$ values at $40^{\circ}C$ were 1.4 to 1.2. The values for browning were 15.7 to 14.4 Kcal/mol and 2.2 to 2.0 respectively. Shelf-life, defined as the time to reach 0.15 O. D./g solid or the limit of off-color deterioration by browning reaction, was extented longer than the halflife of Iysine loss, actually corresponding $75\%$ loss of available lysine. This suggested that the halflife of lysine loss might not be adequate to assess the shelf-life of the food system with high potential of protein, nonproteinous nitrogen compounds, and lipids.

• Korean Journal of Environment and Ecology
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• v.29 no.1
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• pp.29-45
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• 2015

Water chemistry and fish community, based on fish compositions and ecological characteristics(trophic/tolerance guilds and condition factor), were compared in Gucheon Reservoir($G_cR$) and Yeoncho Reservoir($Y_cR$). Chemical parameters of water quality such as BOD, COD, nutrient(N, P) and suspended solids indicated that water quality was better in the $Y_cR$ than $G_cR$, and the temporal variability in seasonal and interannual patterns were greater in the $Y_cR$. The greater variability was mainly attributed to intense dilutions of reservoir water by Asian monsoon rain during July-August. Fish guild analysis indicated that species diversity was higher in the $G_cR$ than the $Y_cR$, and that the proportion of tolerant and omnivore species were greater in the $Y_cR$. Regression analysis of body weight-total length showed that the regression coefficient(b value) was lower in the $G_cR$(2.15 ~ 2.40) than the $Y_cR$(2.59 ~ 3.14). Condition factor(K) of fish against the total length showed negative slope of Zacco temminckii, Carassius auratus, Pseudorasbora parva and Rhinogobius brunneus population in the $G_cR$, and a positive slope of Carassius auratus and Rhinogobius brunneus population in $Y_cR$. Overall, our data suggest that the growth of the fish populations, based on the length-weight relations and condition factor, reflected the trophic regime of nutrients and organic matter.

• Journal of the Korean Ceramic Society
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• v.41 no.8
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• pp.599-604
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• 2004

The LTCCs (Low-Temperature Co-fired Ceramics) are very important for electronic industry to build smaller RF modules and to fulfill the necessity for miniaturization of devices in wireless communication industry. The dielectric materials with sintering temperature $T_{sint}$＜90$0^{\circ}C$ are required. In this study, BaO-N $d_2$ $O_3$-Ti $O_2$ (BNT ： 20∼40 wt％) for ceramic materials and L $a_2$ $O_3$- $B_2$ $O_3$-Ti $O_2$ (LBT ： 80∼60 wt％) for crystallizable glasses were used. The glass/ceramic composites were investigated for sintering behavior, phase evaluation, densities, interface reaction and microwave dielectric properties. It was found that the addition LBT glass frist significantly lowered the sintering temperature to below 90$0^{\circ}C$ and the densification with increasing addition LBT glass frist developed rapidly which was meant to be namely 90％ of relative density. The sintered bodies ekhibited applicable dielectric properties, namely 15 for $\varepsilon$$_{r}$,, 10000 GHz for Q＊ $f_{0}$. The results suggest that the composites have good potential as a new candidate for LTCC materials.

• Animal cells and systems
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• v.14 no.2
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• pp.129-136
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• 2010

The introduced spider crab Pyromaia tuberculata was collected from Korea in 2005 and it was ovigerous. After hatching, larvae were reared in the laboratory at $20^{\circ}C$. The larval stage of the species consists of two zoeal and one megalopal stages. The larvae of the Korean species differ somewhat from those from New Zealand described by Webber and Wear (1981; N Z J Mar Freshwat Res. 15:331-383) and from Brazil described by Fransozo and Negreiros-Fransozo (1997; Crustaceana. 70:304-323.) in the setal presence of the antennule, the maxillule, the maxilla and the maxillipeds, and the abdomen. It is found that Fransozo and Negreiros-Fransozo have overlooked some setae on the basis of the zoeal maxillipeds and that re-examination of their larvae is needed. Also, it is found that the Inachoididae is heterogeneous based on the zoeal morphology because two distinct groups exist in the family.

• Journal of Biosystems Engineering
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• v.31 no.3 s.116
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• pp.168-174
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• 2006

The purpose of this study is to develop the cold chain system by developing optimal phase change materials (PCM). There are some benefits from developing this system such as keeping freshness of agriculture products, saving energy, etc. The major results are as follows. To decide a latent heat material, the characteristics of water, sodium, polyacrylate, ethanol and N-tetradecane are analysed. Also, an insulating material is made by mixing water, nucleating agent and latent heat material, using cementing method. In addition, the sensitivity analysis for developed latent heat material($K_l,\;K_2,\;K_3$) is conducted. For $K_l,\;K_2,\;K_3$ which cans keep latent heat temperature, ranging from $0\;to\;5^{\circ}C,\;5\;to\;10^{\circ}C,\;10\;to\;15^{\circ}C$. it can keeps latent heat temperature at radiant heat (5, 12, $17^{\circ}C$) and transportation latent heat container both melting temperature and amount of latent heat of Kl are $-1.6{\pm}1.0^{\circ}C$, 326.51 J/g, respectively and freezing temperature and latent heat are $-7.98{\pm}1.5^{\circ}C$ and 174.18 J/g. and $K_2$ are $7.41{\pm}1.5^{\circ}C$, 89.80 J/g, respectively and freezing temperature and latent heat are $-2.14{\pm}1.5^{\circ}C$ and 83.90 J/g. and $K_3$ are $9.54{\pm}1.0^{\circ}C$, 145.42 J/g, respectively and freezing temperature and latent heat are $0.21{\pm}1.0^{\circ}C$ and 152.48 J/g.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6721-6726
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• 2013

Background: Changes in DNA methylation patterns are believed to be early events in hepatocarcinogenesis. A better understanding of methylation states and how they correlate with disease progression will aid in finding potential strategies for early detection of HCC. The aim of our study was to analyze the methylation frequency of tumor suppressor genes, P14, P15, and P73, and a mismatch repair gene (O6MGMT) in HCV related chronic liver disease and HCC to identify candidate epigenetic biomarkers for HCC prediction. Materials and Methods: 516 Egyptian patients with HCV-related liver disease were recruited from Kasr Alaini multidisciplinary HCC clinic from April 2010 to January 2012. Subjects were divided into 4 different clinically defined groups - HCC group (n=208), liver cirrhosis group (n=108), chronic hepatitis C group (n=100), and control group (n=100) - to analyze the methylation status of the target genes in patient plasma using EpiTect Methyl qPCR Array technology. Methylation was considered to be hypermethylated if >10% and/or intermediately methylated if >60%. Results: In our series, a significant difference in the hypermethylation status of all studied genes was noted within the different stages of chronic liver disease and ultimately HCC. Hypermethylation of the P14 gene was detected in 100/208 (48.1%), 52/108 (48.1%), 16/100 (16%) and 8/100 (8%) among HCC, liver cirrhosis, chronic hepatitis and control groups, respectively, with a statistically significant difference between the studied groups (p-value 0.008). We also detected P15 hypermethylation in 92/208 (44.2%), 36/108 (33.3%), 20/100 (20%) and 4/100 (4%), respectively (p-value 0.006). In addition, hypermethylation of P73 was detected in 136/208 (65.4%), 72/108 (66.7%), 32/100 (32%) and 4/100 (4%) (p-value <0.001). Also, we detected O6MGMT hypermethylation in 84/208 (40.4%), 60/108 (55.3%), 20/100 (20%) and 4/100 (4%), respectively (p value <0.001. Conclusions: The epigenetic changes observed in this study indicate that HCC tumors exhibit specific DNA methylation signatures with potential clinical applications in diagnosis and prognosis. In addition, methylation frequency could be used to monitor whether a patient with chronic hepatitis C is likely to progress to liver cirrhosis or even HCC. We can conclude that methylation processes are not just early events in hepatocarcinogenesis but accumulate with progression to cancer.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.1
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• pp.47-53
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• 1997

Appropriation of partial substitution of concentrate mixture by urea-molasses-mineral block (UMMB) lick supplements for 20 lactating crossbred cows in 2nd and 3nd lactation was studied. Animals fed on wheat straw ad lib. and Berseem (Trifolium alaxandrium) fodder @ 1.5 kg/d on dry matter basis. Animals of control group were given concentrate supplement, while in treatment groups 10% of the concentrate requirement was substituted with 3 different types of UMMB lick type A ($T_1$), type B ($T_2$) and type C ($T_3$). CP content of the ration was 15%. Total dry matter intake (DMI) was about 1.0 kg/kg of fat corrected milk (FCM) yield and was not significantly different between control and treatment groups. Digestibility of neither proximate principles nor cell wall constituents were deviated on UMMB licks partial supplementation. FCM yield was increased by 140, 410 and 460 g/d, in $T_1$, $T_2$ and $T_3$, respectively, in comparison to control group but differences were statistically invalid. Though fat per cent was reduced, fat yields were remain constant among treatments. Milk composition was unaltered except significant difference (p < 0.01) in non-protein nitrogen (NPN) content. Gross-N and digestible-N conversion was significantly higher (p < 0.01) with $T_1$, $T_2$ and $T_3$ than control group. Energy utilization efficiency for milk production was only 36%. Result demonstrated that UMMB licks could be partial supplemented up to 10% of the concentrate requirement of crossbred cows yielding on an average 14kg/d without any adverse effect on feed intake, nutrient utilization and mild production. Comparatively, UMMB lick type B and C was proved better than type A and also economically viable.

• Korean journal of food and cookery science
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• v.14 no.3
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• pp.207-212
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• 1998

The changes in physicochemical properties of potato were investigated while steeping in water for 7 days at 30${\pm}$1$^{\circ}C$. The shape of raw starch granules was round or oval, the starch granule showed birefringence distinctly under polarized light and it was kept clearly even after steeping. X-ray diffraction pattern of the starch was B-type and there was no change in the pattern after steeping. However, crystallinity was increased up to the 4th day and then decreased. Amylose contents of raw starch and the starch steeped for 7 days were 19.3% and 13.1%, respectively. When the potato starch was gelatinized in 0.15 N sodium hydroxide solution, the viscosity was decreased until the 3rd day, but increased thereafter. Gel volume of the starch in KSCN solution was decreased during steeping.

• Korean Journal of Environmental Agriculture
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• v.15 no.3
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• pp.362-371
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• 1996

This study was conducted to investigate the biochemical properties of isolated bacteria, low temperature tolerant methanogens which were selected for use as inoculum for anaerobic fermentation of agricultural and livestock wasted at low temperature. The results, obtained were summarized as follows: Low temperature tolerant methanogens were isolated from the samples which showed the high methanogenesis rate by enrichment culture at low temperature in methanol medium. These methanogens, Methanobacterium M-251 and Methanobacterium M-253 were isolated from swampy sediment at latitude $56.9^{\circ}$, Methanosarcina mazei M-372 from lake sediment IV at latitude $55.0^{\circ}$ N, and Methanobacterium formicicum M-375 from tidal land soil at latitude $37.0^{\circ}N$, respectively. The isolated anaerobic bacteria could not use sugars as carbon sources. The optimum pH value for the growth of M-251 and M-375 was 6.8, but those for M-253 and M-372 6.5 and 7.0, respectively. The minimum growth temperature of isolated, M-251 and M-253 were $8^{\circ}C$ and the optimum temperature $30^{\circ}C$, while the minimum of M-392 and M-395 were $13^{\circ}C$ and the optimum $37^{\circ}C$. The growth rate of isolates at $17.5^{\circ}C$ were lower by 32-50% than that of $30^{\circ}C$. The isolated Methanobacterium strains such as M-251, M-253, and M-375 have lower cell yield, 0.38-1.21g/1M $CH_4$ than 1.14-1.51g/1M $CH_4$ of Methanosarcina mazei M-372.

• Journal of Trauma and Injury
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• v.33 no.2
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• pp.81-87
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• 2020

Purpose: Chronic subdural hematoma (CSDH) is a common disease in elderly patients and is usually treated by burr-hole drainage. However, the optimal surgical technique for treating CSDH has not been determined. In this study, we analyzed outcomes and recurrence rates after burr-hole drainage with or without irrigation in patients with CSDH. Methods: Eighty-two CSDH patients treated with burr-hole drainage at Wonju Severance Christian Hospital from March 2015 to June 2016 were enrolled in this study. The subjects were divided into three groups based on the surgical technique performed as follows: single burr-hole drainage without irrigation (group A, n=47), single burr-hole drainage with irrigation (group B, n=14), or double burr-hole drainage with irrigation (group C, n=21). These three groups were compared with respect to clinical and radiological factors and the recurrence rate, and independent factors predicting recurrence were sought. Results: After burr-hole drainage, CSDH recurred in 15 (18.3%) of the 82 patients, and six patients (7.3%) required reoperation. More specifically, recurrence was observed in 12 patients (25.5%) in group A, one (7.1%) in group B, and two (9.5%) in group C. The number of burr-holes did not significantly affect recurrence (odds ratio [OR]=0.38; 95% confidence interval [CI]: 0.60-2.38), but irrigation had a significant effect (OR=0.20; 95% CI: 0.04-0.97). Conclusions: This study shows that irrigation during burr-hole surgery in CSDH patients significantly reduced the risk of recurrence, regardless of the number of burr-holes used. We therefore recommend the use of active irrigation during burr-hole drainage surgery in CSDH patients.