• Journal of Nutrition and Health
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• v.20 no.6
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• pp.432-441
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• 1987

This study was undertaken to investigate effects of alcohol and fat content in a balanced diet on growth, hepatic function and some biochemical indices of blood in growing rats. Fourty eight male rats of Sprague-Dawley strain weighing about 160g were divided into 4 groups ; high fat diet group, alcohol-adminstered high fat diet group, low fat diet group and alcohol-administered low fat diet group. High and low fat diet supplied 30% and 12%, respectively, of total calorie intake from fat and alcohol-treated groups received water containing 10% ethanol. Diets contained adequate amounts of all nutrients required for rats, including lipotropic agents(choline and methionine) to minimize effects of factors other than alcohol on liver function. Growth rate was lowest in alcohol-administered low-fat diet group, despite that their energy intake was equivalent to the others. For a 3-week study period, 21.86% and 23.61% of total calorie intake were derived from alcohol in alcohol-adminitered high fat diet group and low fat diet group, respectively. There was no influenced on vitamin B$_1$ status by alcohol consumption. Concentration of triglyceride in plasma increased with alcohol comsumption, and the effect was greater after 6 weeks than after 3 weeks of alcohol consumption . Difference of dietary fat content did not affect the level of triglyceride . The levels of total cholesterol and HDL-cholesterol in plasma were not influenced by alcohol consumption. Serum glutamate pyruvate transaminase activity and hepatic mitochondrial respiration rate did not differ between groups. The results indicate that neither moderate alcohol drinking for 6 weeks nor fat content with a balanced diet caused any dramatic change of metabolism and liver function in rats. However they suggest that even moderate alcohol consumption can affect growth of animals dramatically and the effect may be lessened with relatively high fat content in diet.

• KSBB Journal
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• v.21 no.6 s.101
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• pp.474-478
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• 2006

For the economically feasible production of ethanol, utilization of SFW (saccharified food wastes) as substrate for synchronous saccharification and fermentation (SSF) process was developed in this study. When 200 g of food wastes and 40 mL of enzyme ($amylase activity,\;3.0\;U/m{\ell}$) were reacted, production rate of reducing sugar was $5.84\;g/{\ell}{\cdot}h$, and consumption rate was $-3.88\;g/{\ell}{\cdot}h\;at\;35^{\circ}C$ So suitable condition of SSF was concluded at temperature of $35^{\circ}C$. Also, optimal enzyme concentration of SSF was concluded in $2.0\;U/m{\ell}$, at this condition, the production rate of reducing sugar was $4.80\;g/{\ell}{\cdot}h$ At SSF process, when 50 g of food wastes was supplied in 12 h interval, $64\;g/{\ell}$ of ethanol and 0.45 g-ethanol/g-reducing sugar in yield were obtained in 120 h fermentation. Thus, the technology of high yield of ethanol production using food wastes was confirmed. And semi-continuos SSF system for cutting off cost of enzymatic saccharification was developed in this study.

• Korean Journal of Oriental Medicine
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• v.12 no.1
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• pp.49-57
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• 2006

Objectives : This study has attempted to establish an organized system for the microbiological quality of raw materials which are important factors in preparing the standard for microbial limits. Methods : This study has first set up microbial contamination limit test. total aerobic microbial count and total fungi count, int accordance with testing method of the Korea Pharmacopeia 8th edition in order to establish an inspection standard for microbial contamination. Results : The microbial contamination of 18 items that are highly prone to contamination by three regions(Seoul, Daejeon, Gyeongsangbuk-do), As a result, Morus alba Linne and Rehmannia glutimosa Liboschitz var. purpurea Makino showed as high contaminated by WHO's Microbial Contamination Limit standard. In case of Yukjin medicine in the Theory of Herb Medicinal Properties, total bacterial contamination rate showed as 17.7%, total fungal contamination rate showed as 41.2% and total aerobic mircobial count and total fungi count on Ephedra sinica Stapf. Pinellia ternate Breitenbach, Evodia officinalis Dode showed as high measured. The microbial conatmination rate materials which make up Yukmijihwanghwan were mostly high therefore the total aerobic microbial count was measured as high in case of Yukmijihwanghwan, the characteristics about microbial contamination strain is to be researched. Conclusions : By combining the basic data and experimental results related to microbial contamination of herb medicine, the most ideal storage standards for herb medicine has been attempted to be presented.

• Journal of the Korean Geotechnical Society
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• v.22 no.9
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• pp.45-59
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• 2006

The successful performance of any numerical geotechnical simulation depends on the accuracy and efficiency of the numerical implementation of constitutive model used to simulate the stress-strain (constitutive) response of the soil. The corner stone of the numerical implementation of constitutive models is the numerical integration of the incremental form of soil-plasticity constitutive equations over a discrete sequence of time steps. In this paper a well known two-surface soil plasticity model is implemented using a generalized implicit return mapping algorithm to arbitrary convex yield surfaces referred to as the Closest-Point-Projection method (CPPM). The two-surface model describes the nonlinear behavior of coarse-grained materials by incorporating a bounding surface concept together with isotropic and kinematic hardening as well as fabric formulation to account for the effect of fabric formation on the unloading response. In the course of investigating the performance of the CPPM integration method, it is proven that the algorithm is an accurate, robust, and efficient integration technique useful in finite element contexts. It is also shown that the algorithm produces a consistent tangent operator $\frac{d\sigma}{d\varepsilon}$ during the iterative process with quadratic convergence rate of the global iteration process.

• KSBB Journal
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• v.20 no.6
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• pp.458-463
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• 2005

[ $H_2$ ] from CO and water was continuously produced in a trickle bed reactor(TBR) using Citrobacter amalonaticus Y19. When the strain C. was cultivated in a stirred-tank reactor under a chemoheterotrophic and aerobic condition, the high final cell concentration of 13 g/L was obtained at 10 hr. When the culture was switched to an anaerobic condition with the continuous supply of gaseous CO, CO-dependent hydrogenase was fully induced and its hydrogen production activity approached 16 mmol/g cell/hr in 60 hr. The fully induced C. amalonaticus Y19 cells were circulated through a TBR packed with polyurethane foam, and the TBR was operated for more than 20 days for $H_2$ production. As gas retention time decreased or inlet CO partial pressure increased, $H_2$ production rate increased but the conversion from CO to $H_2$ decreased. The maximum $H_2$ production rate obtained was 16 mmol/L/hr at the gas retention time of 25 min and the CO inlet partial pressure of 0.4 atm. The high $H_2$ production rate was attributed to the high cell density in the liquid phase circulating the TBR as well as the high surface area of polyurethane foam used as packing material of the TBR.

• Journal of the Korea Concrete Institute
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• v.15 no.2
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• pp.280-287
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• 2003

To evaluate the practical application of oyster shells(OS) as construction materials, an experimental study was performed. More specifically, the long-term mechanical properties and durability of concrete blended with oyster shells were investigated. Test results indicate that long-term strength of concrete blended with 10% oyster shells is almost identical to that of normal concrete. However, the long-term strength of concrete blended with 20% oyster shells is appreciably lower than that of normal concrete. Thereby, concrete with higher oyster shell blend has the possibility of negatively influencing the concrete long-term strength. Elastic modulus of concrete blended with crushed oyster shells decreases as the blending mixture rate increases. Namely, the modulus is reduced to approximately 10∼15% when oyster shells are blended up to 20% as the fine aggregate. The drying shrinkage strain increases with an increasing crushed oyster shells substitution rate. In addition, the existing model code of drying shrinkage and creep do not coincide with the test results of this study. An adequate prediction equation needs to be developed. The utilization of oyster shells as the fine aggregate in concrete has an insignificant effect on fleering and thawing resistance, carbonation and chemical attack of concrete. However, water permeability is considerably improved.

• Korean Journal of Microbiology
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• v.36 no.2
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• pp.155-160
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• 2000

Pseudomnas sp. HJ-2 is capable of producing a rubber-elastic polyhydroxyalkanoate (PHA) consisting of 3- hydroxybutyrate (3HB), 3-hydroxyvalerate (3HV), and 3-hydroxyheptanoate (3HHp) from heptanoic acid as the sole carbon source. The polyester produced was a blend of poly(3HB-co-3HV) and poly(3HHp). Although the mixing of poly(3HHp) fraction to poly(3HB-co-3HV) resulted in a decrease of modulus, the sole fraction of poly(3HB-co-3HV) with a high molar fraction of 3HV was shown to be an elastomer with the maximum percent strain of 740%. The biomass yield and the PHA synthesis were relatively high when the initial heptanoic acid concentration was 40 mM, and were significantly decreased when the substrate concentration exceeded 50 mM. The accumulation of PHA was stimulated by deficiency of nitrogen and phosphorus in the medium. The PHA contents and its monomeric compositions were greatly affected by pH and oxygen transfer rate. At pH 7.5, poly(3HB-~0.38% 3HV) was produced from heptanoic acid and a mixture of 95% 3HHp and 5% 3HV was produced at pH 8.0. Increased conten1 of 3HHp in the polyesters with lhe increasing oxygen transfer rate by agitation speed a1 a fixed aeration rate was observed.

• Journal of Life Science
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• v.29 no.10
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• pp.1120-1125
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• 2019

The short-lived nematode Caenorhabditis elegans has been used as a model organism for many studies, including lifespan extension. To screen common seaweeds for natural anti-aging agents, the lifespan of C. elegans (N2 wild-type strain) was measured by its hatch rate, growth rate, survival rate, chemotaxis, brood size, and egg-laying time after exposure to nematode growth medium (NGM) containing seaweed extracts. Approximately 30 animals synchronized at the first larval stage were incubated until they reached their adult stages before laying their eggs and were transferred to fresh NGM every 3 days. We also identified the major active compound from the seaweed by gas chromatography-mass spectrometry and tested its optimal dose for longevity. Of 13 common seaweed species, an ethanol extract of the brown seaweed Hizikia fusiformis showed the greatest effect on hatching, growth, and survival rates. The lifespan of C. elegans was significantly expanded 1.54-fold and 1.23-fold in the presence of the ethanol extract (0.05 mg/ml) and the main active component, fucosterol (0.05 mg/ml), respectively. Exposure to the ethanol extract also increased chemotaxis 1.13-fold, decreased brood size 0.74-fold, and shortened egg-laying time 0.96-fold. These results suggest that the aquaculturable H. fusiformis may be a promising source of a diet supplement to support health care.

• The Korean Journal of Zoology
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• v.13 no.1
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• pp.21-25
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• 1970

The present paper deals with the results of the experiments, in which the resistibility to NaCl in whole develomental stages is examined by the emergence rate and the effects of NaCl on the SD action in Drosophila melanogaster. The four SD strains and one mutant strain(cn bw)are used and NaCl media are prepared y adding NaCl at a concentration of 1.0M, 0.7M, 0.5M, 0.3M, 0.1M, and 0.0M to the standard media for the present investigations. The results are given below. 1. The emergence rate (resistibility to NaCl) is not significantly different among strains but strikingly different among concentrations of NaCl. 2. The emergence rate decreases as the concentration of NaCl increases; the four SD strains are considerably resistible to the NaCl from a concentration of 0.0M to 0.3M but are susceptible from 0.5M or higher concentrations of NaCl. 3. No eggs are hatched from the culture media containing a concentration of 1.0M NaCl. This suggests that the SD strains are not resistible to NaCl at a concentrations of 1.0M or higher. 4. The difference in k values is not signficant among strains and also among concentrations of NaCl. Thus the SD action is not affected as far as once emerged from the culture media whether containing NaCl or not.

• Fire Science and Engineering
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• v.27 no.6
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• pp.50-56
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• 2013

The radiation effects on the auto-ignition and extinction characteristics of a non-premixed fuel-air counterflow field were numerically investigated. A detailed reaction mechanism of GRI-v3.0 was used for the calculation of chemical reactions and the optically-thin radiation model was adopted in the simulations. The flame-controlling continuation method was also used in the simulation to predict the auto-ignition point and extinction limits precisely. As a result, it was found that the maximum H radical concentration, $(Y_H)_{max}$, rather than the maximum temperature was suitable to understand the ignition and extinction behaviors. S-, C- and O-curves, which were well known from the previous theory, were identified by investigating the $(Y_H)_{max}$. The radiative heat loss fraction ($f_r$) and spatially-integrated heat release rate (IHRR) were introduced to grasp each extinction mechanism. It was also found that the $f_r$ was the highest at the radiative extinction limit. At the flame stretch extinction limit, the flame was extinguished due to the conductive heat loss which attributed to the high strain rate although the heat release rate was the highest. The radiation affected on the radiative extinction limit and auto-ignition point considerably, however the effect on the flame stretch extinction limit was negligible. A stable flame regime defined by the region between each extinction limit became wide with increasing the fuel temperature.