• Journal of the Korea Organic Resources Recycling Association
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• v.2 no.2
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• pp.3-17
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• 1994

The inhibitory effect of sodium ion on the anaerobic degradation of food waste was studied by an anaerobic batch toxicity assay and inhibition model. The anaerobic degradation activity of food waste spiked with over $2g\;Na^+/L$ of sodium ion was severely inhibited at the initial stage of the exposure. The inhibition response of anaerobic microorganisms on the sodium ion estimated from the methane production was differed according to the concentration of sodium ion. The relative acclimation time(RAT) and methanation rate(RMR), defined as the ratios of initial lag time and maximum methane production rate of the sample spiked with sodium ion to the control. respectively, were used to evaluate the acclimation and inhibitory effects quantitatively on the anaerobic microorganisms. When sodium ion was increased from $2g\;Na^+/L$ to $20g\;Na^+/L$, the RAT was exponentially increased from 18.9 to 90. but the RMR was linearly decreased from 0.97 to 0.02. The effects of sodium ion for the maximum methanation rate, first order kinetic constant and ultimate methane production were well evaluated by a generalized nonlinear expression model. it could be described by the uncompetitive inhibition mode. The sodium ion concentration causing 50% inhibition of methanation activity was about $11g\;Na^+/L$, and the critical sodium ion beyond to compelete inhibition was 20 to $21g\;Na^+/L$. The presented results could be used to obtain the design or operation parameters of the anaerobic process treating food waste of high salt.

• Journal of Animal Science and Technology
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• v.48 no.2
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• pp.211-218
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• 2006

This experiment was conducted to study the effects of the natural deep sea water, which contained approximately 2.3% salt, and various minerals of K, Mg, Ca, Na, Fe, Mn, Zn, Cu etc, on the immune response and antioxidant activity in rats. 24 Sprague Dawley rats were randomly allotted to a control group and 3 treatment groups. Control rats were supplied with filtered tap water, and each treatment group rats were supplied with 0.5% deep sea water, 1% deep sea water and Jijangsoo, respectively, which is upper clear water separated from sediment by the clay. Feed and water were provided ad libitum throughout the experiment that lasted for 4 weeks. The results showed that 1% deep sea water group showed the highest values in weight gain, feed intake, and feed efficiency than those of other groups. The levels of water intake of 1%- and 0.5%-deep sea water, and Jijangsoo group were 49.1%, 22.8%, and 40.5% higher than that of control group, respectively. The Jijangsoo group rats showed that perirenal and epididymal adipose tissue weights were decreased by 32% and 25%(p<0.05), respectively, when compared to control group rats. There were no remarkable differences of serum glucose concentration among all experimental groups. However, insulin concentration of experimental groups were remarkably increased in order of Jijangsoo (4.54), 1% deep sea water (3.70), 0.5% deep sea water (3.25)(p<0.05). B cell and T cell stimulation were increased about 44.7% and 207%, respectively, by 0.5% deep sea water in comparison with control (p<0.05). TBARS values of 0.5 % deep sea water group were significantly lower than that of control(p<0.05). Catalase and SOD activities of 0.5 % deep sea water group were 200% and 47% higher than that of control, respectively. From the results, it can be concluded that the supply of natural deep sea water can slightly improve the physiological activity which modulates immune response and antioxidant activity in rats.

• Restorative Dentistry and Endodontics
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• v.32 no.2
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• pp.102-110
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• 2007

The purpose of this study was to obtain the basic information for the improvement of dental environment by investigating the presence of methicillin- or vancomycin-resistant Staphylococcus aureus (MRSA or VRSA) isolated from dental health care workers (DHCWs) and environment of the Chosun University Dental Hospital (CUDH) and a private dental clinic (control group). Staphylococcus aureus (S. aureus) was isolated from anterior nares of 42 DHCWS and 38 sites, unit chairss, x-ray devices, computers, etc., at 10 departments of the CUDH and 20 DHCWs and 11 sites at the private dental clinic. S. aureus was isolated on mannitol salt agar plate and confirmed by PCR with S. aureus species-specific primer. Antimicrobial susceptibility test of clinical isolates of S. aureus against several antibiotics including methicillin (oxacillin) was performed by investigating minimum inhibitory concentration (MIC) using broth microdilution assay. In addition, PCR was performed to detect the methicillin- or vancomycin-resistant gene. The data showed that one strain of S. aureus was isolated from DHCWs of the CUDH and three strains of S. aureus was isolated from 3 samples of the private dental clinic, respectively. All of the isolates from the CUDH and the private dental clinic had resistance to penicillin G, amoxicillin and vancomycin and susceptibility to oxacillin and ciprofloxacin. The S. aureus strains were already obtained the resistance to penicillin G and amoxicillin. These results suggest that two dental clinics were under relatively safe environment.

• Korean Journal of Food Science and Technology
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• v.35 no.3
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• pp.510-518
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• 2003

Protective effects of natural components including genistein (4',5,7-trihydroxyisoflavone) from Glycine max MERRILL on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. Genistein $(10{\sim}100\;{\mu}m)$ suppressed photohemolysis in a concentration-dependent manner, and was more effective than the lipid peroxidation chain blocker, ${\alpha}$-tocopherol (Vit. E). Glycoside of genistein, genistin, the water-soluble antioxidant, L-ascorbate, and the iron chelator, myo-inositol hexaphosphoric acid dodecasodium salt (sodium phytate) did not exhibit protective effect against photohemolysis. L-Ascorbate and sodium phytate stimulated photohemolysis at high concentration $(500\;{\mu}m)$. ${\alpha}$-Carotene 3,3'-diol (lutein), a singlet oxygen $(^1O_2)$ quencher, exhibited pronounced protective effect, an indication that $^1O_2$ is important in photohemolysis sensitized by rose-bengal. Reactive oxygen scavenging activities $(OSC_{50})$ of natural antioxidants including genistein on reactive oxygen species (ROS) generated in $Fe^{3+}-EDTA/H_2O_2$ system using the luminol-dependent chemiluminescence assay were in the order of sodium phytate > L-ascorbate > ${\alpha}$-tocopherol > genistein > genistin. $OSC_{50}$ value of genistein, genistin, ${\alpha}$-tocopherol, L-ascorbate, and sodium phytate were 41.0, 109.0, 9.0, 5.2, and $0.56{\mu}m$ respectively. The order of free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity $(FSC_{50})$ was L-ascorbate > ${\alpha}$-tocopherol > genistein > genistin. These results indicate that genistein can function as an antioxidant in biological systems, particularly skin exposed to solar UV radiation by scavenging $^1O_2$ and other ROS, and to protect cellular membranes against ROS.

• Journal of the Korean Society for Marine Environment & Energy
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• v.8 no.2
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• pp.60-66
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• 2005

When external pressure higher than osmosis pressure is reversely derived into solution, its solvent is moved into the solution having lower concentration, which is called 'reverse osmosis'. We investigated the desalination application of deep ocean water using reverse osmosis pressure of $40-70\;kgf/cm^2$ We observed how to operational factor j like flow rate, water temperature and pressure have effect on efficiency of reverse osmosis membrane and salts rejection. Fluxes of reverse osmosis membrane are directly proportional to water temperature and pressure. However, salts rejection rates are positively correlated with pressure and inversely proportional to water temperature. Separation efficiencies of osmosis membrane for major elements such as $Mg^{2+},\;Ca^{+2},\;Na^+\;and\;K^+$ are as follows in a strong electrolysis solution like seawater; $Ca^{2+},\;Mg^{2+}>K^+>Na^+$. Rejection rates of $Mg^{2+}\;and\;Ca^{2+}$ that have high electric charges are over 99% and show positively correlation with water temperature. Rejection rates of $Na^+$ having low electric charge is observed to be 98%-99%, which rates is much lower than those of $2^+$ charged ions like $Ca^{2+}\;and\;Mg^{2+}$. Ion rejection rates of boron, B, are much low because boron is present il free state or gas phase in seawater. Boron concentration in desalination water is over criteria of Korean drinking water, 0.3 mg/L. However, we could satisfied with the criteria of drinking water under the operation condition like temperature $5^{\circ}C$ and pressure $70kgf/cm^2$, using the relationship that rejection rates of boron is proportional to pressure and is inversely proportional to water temperature

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.7
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• pp.1006-1016
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• 2011

Saltwort (Salicornia herbacea L.), as a natural additive for regulating Mul-kimchi fermentation, was assessed for physicochemical and sensory characteristics of Yulmoo Mul-kimchi during storage. Saltwort in the form powder was directly added to the Yulmoo Mul-kimchi preparation at 0 (control), 1, 3, 5, and 7% (w/v) per weight of salt to evaluate their physicochemical, sensory, and microbiological characteristics in storage at $10^{\circ}C$ for 30 days. The pH values of all treatments were high, indicating a less acidic environment in all treatments compared to those of the control sample throughout the preservation period. Total acidity increased with storage time as is usually seen with normal kimchi fermentations, whereas the increases were more gradual in the 3 and 5% treatments. The increases in total vitamin C continued until days 6 (control) to 13 (7%), and were different according to the amount of added saltwort and then they decreased after each peak. The fluctuation in reducing sugars fol owed a similar trends of total vitamin C content by showing an initial increase, followed by a decrease based on the saltwort concentration and storage day. The 5% treatment was most effective for suppressing the increase in turbidity among all treatments. The 3 and 5% treatments showed the highest lactic acid bacteria counts during the entire preservation period. In the sensory evaluation results, adding saltwort at more than 3% concentration attained an overall higher scores of acceptability with respect to color, smell, taste, fresh taste, sour taste, crisp, and overall acceptability characteristics. In conclusion, adding saltwort, particularly at concentrations of 3 and 5% extended the preservation period of Yulmoo Mul-kimchi by retarding fermentation effectively.

• Applied Biological Chemistry
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• v.22 no.3
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• pp.135-141
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• 1979

These experiments were conducted to investigate the conditions of the acid protease production by Rhizopus oryzae and the characteristics of crude enzyme. The results obtained were as follows: 1. The optimum culture time and the optimum amount of added water to the wheat bran medium were about 48 hrs and $80{\sim}120%$, respectively. 2. The addition of $(NH_4)_6Mo_7O_{24},\;(NH_4)_2SO_4,\;NH_4NO_3$, casein, and albumin, respectively, as nitrogen sources to the wheat bran medium was effective. Of these, the optimum concentrations of addition of $(NH_4)_6Mo_7O_{24}$ and casein which were the most effective were 0.1% and 1.0%, respectively. 3. The addition of glucose, galactose, maltose, lactose, and soluble starch, respectively, as carbon sources to the wheat bran medium was effective. Of these, the optimum concentration of addition of glucose which was the most effective was 3.0%. 4. The addition of $KH_2PO_4$ as a phosphate salt to the wheat bran medium was effective. The optimum concentration of addition of $KH_2PO_4$ was 0.3%. 5. The optimum pH for the enzyme action was 2.4, the optimum temperature about $40^{\circ}C$, and the stable pH range $2.0{\sim}5.0$. The enzyme was stab1e below $40^{\circ}C$. 6. The enzyme activity increased rapidly for 10 minutes after addition, thereafter it increased slowly. 7. The enzyme activity increased rapidly to 2 ml of addition, but nearly did not increase at the amounts greater than 2ml.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.1
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• pp.8-14
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• 2006

High phosphate accumulations in greenhouse soils have been considered as a new agricultural problem in Korea. The effects of silicate on changes in phosphate fractions and on the yield of Chinese cabbage without P fertilization were investigated by pot experiment. For this experiment, P-accumulated soil was selected (Total-P; $2140mg\;kg^{-1}$). Three levels of silicate (0, 2, and $4Mg\;ha^{-1}$) without P fertilization and P fertilizer without silicate application (Si0+NPK) were applied in 1/2000a pots. The same amount of nitrogen and potassium fertilizers were applied to the all pots. The application of $4Mg\;ha^{-1}$ of silicate greatly increased the yield of Chinese cabbage by 25% compared to Si0+NPK treatment. Although there is no significant difference in plant P absorption among all the treatments, the uptake of P in the $4Mg\;ha^{-1}$ silicate application was significantly higher than Si0+NPK treatment due to increase in yield. The content of available $SiO_2$ in soil increased with increasing silicate application rates. The Si concentration of plant showed a positive correlation with available $SiO_2$ contents in soil and the yield of Chinese cabbage. Total P greatly decreased with increasing rates of silicate application, yet the change in available P content was not significant. The Si0+NPK treatment increased the content of Ca-P by 11%, however, which was decreased by 27% in the $4Mg\;ha^{-1}$ silicate application. Therefore, the effect of silicate on reducing total-P was mainly attributed to the change in concentration of Ca-P. Our results suggest that the application of silicate in P-accumulated soils not only increase the crops yield but also reduces phosphate accumulation.

• Journal of IKEEE
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• v.27 no.1
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• pp.116-121
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• 2023

In this paper, we develop a deep learning structure for a complex microbial incubator that applies deep learning prediction result information. The proposed complex microbial incubator consists of pre-processing of complex microbial data, conversion of complex microbial data structure, design of deep learning network, learning of the designed deep learning network, and GUI development applied to the prototype. In the complex microbial data preprocessing, one-hot encoding is performed on the amount of molasses, nutrients, plant extract, salt, etc. required for microbial culture, and the maximum-minimum normalization method for the pH concentration measured as a result of the culture and the number of microbial cells to preprocess the data. In the complex microbial data structure conversion, the preprocessed data is converted into a graph structure by connecting the water temperature and the number of microbial cells, and then expressed as an adjacency matrix and attribute information to be used as input data for a deep learning network. In deep learning network design, complex microbial data is learned by designing a graph convolutional network specialized for graph structures. The designed deep learning network uses a cosine loss function to proceed with learning in the direction of minimizing the error that occurs during learning. GUI development applied to the prototype shows the target pH concentration (3.8 or less) and the number of cells (10⁸ or more) of complex microorganisms in an order suitable for culturing according to the water temperature selected by the user. In order to evaluate the performance of the proposed microbial incubator, the results of experiments conducted by authorized testing institutes showed that the average pH was 3.7 and the number of cells of complex microorganisms was 1.7 × 10⁸. Therefore, the effectiveness of the deep learning structure for the complex microbial incubator applying the deep learning prediction result information proposed in this paper was proven.

• Journal of Chest Surgery
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• v.32 no.7
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• pp.603-612
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• 1999

Background : It has been documented that brief repetitive periods of ischemia and reperfusion (ischemic preconditioning, IP) enhances the recovery of post-ischemic contractile function and reduces infarct size after a longer period of ischemia. Many mechanisms have been proposed to explain this process. Recent studies have suggested that transient increase in the intracellular calcium may have triggered the activation of protein kinase C(PKC); however, there are still many controversies. Accordingly, the author performed the present study to test the hypothesis that preconditioning with high concentration of calcium before sustained subsequent ischemia(calcium preconditioning) mimics IP by PKC activation. Material and Method : The isolated hearts from the New Zealand White rabbits(1.5∼2.0 kg body weight) Method: The isolated hearts from the New Zealand White rabbits(1.5∼2.0 kg body weight) were perfused with Tyrode solution by Langendorff technique. After stabilization of baseline hemodynamics, the hearts were subjected to 45-minute global ischemia followed by a 120-minute reperfusion with IP(IP group, n=13) or without IP(ischemic control, n=10). IP was induced by single episode of 5-minute global ischemia and 10-minute reperfusion. In the Ca2+ preconditioned group, perfusate containing 10(n=10) or 20 mM(n=11) CaCl2 was perfused for 10 minutes after 5-minute ischemia followed by a 45-minute global ischemia and a 120-minute reperfusion. Baseline PKC was measured after 50-minute perfusion without any treatment(n=5). Left ventricular function including developed pressure(LVDP), dP/dt, heart rate, left ventricular end-diastolic pressure(LVEDP) and coronary flow(CF) was measured. Myo car ial cytosolic and membrane PKC activities were measured by 32P-${\gamma}$-ATP incorporation into PKC-specific pepetide. The infarct size was determined using the TTC (tetrazolium salt) staining and planimetry. Data were analyzed using one-way analysis of variance(ANOVA) variance(ANOVA) and Tukey's post-hoc test. Result: IP increased the functional recovery including LVDP, dP/dt and CF(p<0.05) and lowered the ascending range of LVEDP(p<0.05); it also reduced the infarct size from 38% to 20%(p<0.05). In both of the Ca2+ preconditioned group, functional recovery was not significantly different in comparison with the ischemic control, however, the infarct size was reduced to 19∼23%(p<0.05). In comparison with the baseline(7.31 0.31 nmol/g tissue), the activities of the cytosolic PKC tended to decrease in both the IP and Ca2+ preconditioned groups, particularly in the 10 mM Ca2+ preconditioned group(4.19 0.39 nmol/g tissue, p<0.01); the activity of membrane PKC was significantly increased in both IP and 10 mM Ca2+ preconditioned group (p<0.05; 1.84 0.21, 4.00 0.14, and 4.02 0.70 nmol/g tissue in the baseline, IP, and 10 mM Ca2+ preconditioned group, respectively). However, the activity of both PKC fractions were not significantly different between the baseline and the ischemic control. Conclusion: These results indicate that in isolated Langendorff-perfused rabbit heart model, calcium preconditioning with high concentration of calcium does not improve post-ischemic functional recovery. However, it does have an effect of limiting(reducing) the infart size by ischemic preconditioning, and this cardioprotective effect, at least in part, may have resulted from the activation of PKC by calcium which acts as a messenger(or trigger) to activate membrane PKC.