• Journal of Food Hygiene and Safety
• /
• v.13 no.3
• /
• pp.274-277
• /
• 1998

The study was focused to investigate the effect of nitrosodimethylamine (NDMA) formation due to nitrosamine (NA) precursor and/or inhibitor addition to Kimchi during the fermentation of Kimchi at room temperature ($16{\pm}2^{\circ}C$). The addition of nitrite and dimethylamine (DMA) to Kimchi showed the average 32-fold ($21.3{\sim}113.9\;\mu\textrm{g}/kg$) and 9-fold ($1.3{\sim}40.3\;\mu\textrm{g}/kg$) higher NDMA formation than control ($O{\sim}5.6\;\mu\textrm{g}/kg$), respectively. Also, the addition of both nitrite and DMA resulted in the increase of NDMA formation to average 42-fold ($39.4{\sim}155.7\;\mu\textrm{g}/kg$) higher than control. On the other hand, the addition of 4 ruM ascorbic acid to Kimchi with nitrite and DMA inhibited the formation of NDMA down to 71.3% of control. However, the addition of cysteine and erythorbic acid affected no inhibition to NDMA formation during the test. The addition of sodium sulfite increased NDMA formation. Accordingly, this showed that the amount of ascorbic acid generated during Kimchi fermentation played an important inhibition role for NA formation.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.24 no.6
• /
• pp.829-836
• /
• 1995

This study was performed to evaluate the relationship between dietary, blood and urinary levels of lead and blood pressure and serum lipids in 30 healthy adult living in rural area of Korea. Analysis for the nutritional status of subjects were performed by 3-day dietary intake record, duplicated diet collection, 24-hour urine collection, and venous blood sampling before anthropometry. The mean daily intakes of lead estimated for 3 days was $120.1{\pm}22.0\mu\textrm{g}$. The blood levels and 24-hour urinary excretion of lead were $10.8{\pm}3.6\mu\textrm{g}/dl\;and\;36.5{\pm}9.5\mu\textrm{g}$, respectively. The systolic and diastolic blood pressure were $113.0{\pm}16.9mmHg\;and\;76.7{\pm}12.1\;mmHg$. The serum levels of total cholesterol, triglyceride, HDL-cholesterol, LDL-cholesterol and ${\beta}-lipoprotein$ were $158.8{\pm}32.9mg/dl,\;104.6{\pm}48.8mg/dl,\;45.7{\pm}9.9mg/dl,\;92.2{\pm}28.5mg/dl\;and\;426.4{\pm}141.5mg/dl$, respectively. There was no significance in the relation between lead and blood pressure. In the relation between lead and serum lipids, it showed negative correlation with lead intake and HDL-choleterol at the level of significance of p<0.01. But there was no significance in the relation between lead and serum levels of otehr lipids.

• Journal of Korean Society for Atmospheric Environment
• /
• v.10 no.2
• /
• pp.130-136
• /
• 1994

Concentration of volatile particulate nitrate(NH$_4$NO$_3$) in TSP in ambient air was determined from Feb. to Oct 1993. Sampling was carried out using a two-stage Andersen air sampler at the top of a five-story building located at Kon- Kuk University in Seoul Concentration of NH$_4$NO$_3$ in TSP was measured by Pyrolysis of sample filters at 16$0^{\circ}C$ for 1hr. Concentration of NH$_4$NO$_3$ was higher in winter time compared with that in summer time. Also, concentration of NH$_4$NO$_3$ was higher in fine particles compared with that in coarse particle. The range of NH$_4$NO$_3$concentration was between 2.99 and 9.86 $\mu\textrm{g}$/㎥. Weight fraction of NH$_4$NO$_3$ in total particulate nitrate was 31.1~59.5%, and weight fraction of NH$_4$NO$_3$ in YSP was 2.1~11.2%.

• Biomolecules & Therapeutics
• /
• v.2 no.3
• /
• pp.260-269
• /
• 1994

This study was performed to determine the toxic effect of DA-3030(granulocyte-colony stimulating factor, G-CSF) in beagle dogs. DA-3030(G-CSF) was injected intravenously at doses of 115 $\mu\textrm{g}$/kg/day, 11.5 $\mu\textrm{g}$/kg/day and 1.15 $\mu\textrm{g}$/kg/day seven days per week for 28 days. After completion of the treatments, the dog were necropsied. The number of dead animal was zero in all groups. No specific clinical sign was found, either. In hematological results, WBC was significantly increased dose-dependently in treated groups. In histopathological findings, megakaryocyte and rubricyte were found in the liver and spleen at the dose of 115 $\mu\textrm{g}$/kg/day. Therefore, we could find the extramedullary hematopoiesis was increased. Megaka yocyte and rubricyte were increased in bone marrow, too. In conclusion, those signs were estimated the pharmacological effect of DA-3030(G-CSF). According to the results, non toxic dose of DA-3030(G-CSF) was higher than 115 $\mu\textrm{g}$/kg/day.

• Journal of the Korean Society for Precision Engineering
• /
• v.10 no.1
• /
• pp.42-51
• /
• 1993

Recently, WC-Co have some excellent properities as the material for the mechanical component such as metallic moulding parts, ball dies parts, and punch parts. This paper describes the surface roughness and grinding force caused by experimental study on the surface grinding of WC-Co with ultra-precision like a mirror shape using diamond wheel. Also, some investigations are carried out using WA grinding wheel to increase improved ground surface roughness such as polishing, lapping effect. Some important results obtained here are summarized as follow. 1) Within this experimental grinding condition, we can be obtained $R_{max}.\;2\mu\textrm{m}\;R_a\;0.3\mu\textrm{m}$ whichare the most favourable ground surface roughness using #140 diamond wheel, and improved surface roughness values about 20 .approx. 25% throughout 5 times sparkout grinding 2) The value of surface roughness is Rmax. $0.49\mu\textrm{m},\;R_a\;0.06\mu\textrm{m}$ using #600 diamond wheel. 3) The area of no rack zone is less than $F_{n}$ 0.27N/mm, Ft 0.009N/mm

• Proceedings of the Korean Radioactive Waste Society Conference
• /
• 2003.11a
• /
• pp.60-70
• /
• 2003

The stability of various waste forms to meet waste acceptance criteria was evaluated by using standard test methods of U.S.A and France. Compressive strength of waste forms were above 176.03 kgf/$\textrm{cm}^2$(cement), 15 kgf/$\textrm{cm}^2$(paraffin). In the thermal cycling test, there were no any change in their feature and volume, the loss of weight was 6.15% on the average. In the immersion test for 120 days, the loss of weight of paraffin waste form was 8.85-5.14% pH=3.83. The G-Value of $H_2$ and $CH_4$ in paraffin wax at $10^8rads$ rads of exposure dose were 2.65, 0.016.

• YAKHAK HOEJI
• /
• v.37 no.4
• /
• pp.341-349
• /
• 1993

To determine the reason of individual variation of the effect of caffeine, the absorption and the disposition of caffeine were studied in caffeine sensitive and caffeine nonsensitive volunteers. And also to study the effect of obesity on caffeine pharmacokinetics, the caffeine disposition in the obese rat and in the lean rat were investigated respectively. In result the caffeine sensitive group showed a longer terminal half-life of caffeine(7.35$\pm$0.71 hr : 5.49$\pm$0.73 hr) and a larger AUC (55.42$\pm$9.09 $\mu\textrm{g}$.$ml^{-1}$.hr:44.0$\pm$7.81$\mu\textrm{g}$.$ml^{-1}$.hr) than that of caffeine non-sensitive group without statistical significance. The obese rat showed a longer terminal half-life (3.47 hr : 2.31 hr) and a larger AUC(35.3 $\mu\textrm{g}$.$ml^{-1}$.hr:26.97$\mu\textrm{g}$.$ml^{-1}$.hr) than that of the lean rat. But there was no correlation in the amount of daily caffeine consumption and obesity. In conclusion, we suggest that the individual variation of the effect of caffeine are being caused from the individual differences of caffeine susceptibility or tolerance rather than the differences of the genetic metabolic capacity or metabolic tolerance.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.22 no.1
• /
• pp.52-60
• /
• 1977

The affect of annual weeds to rice yield with morphological characteristics was evaluated. Rice heading date was shortened 1～5 days and rice culm length was shortened 5～10cm in heavy weed growing condition. No. of grains per panicle and no. of panicle per hill were the major yield components in yield reduction.

• Korean Journal of Materials Research
• /
• v.11 no.10
• /
• pp.869-878
• /
• 2001

Alumina $(Al_2O_3)$ green bodies were fabricated by gel-casting using three kinds of alumina with different particle size (mean particle size: 4.6 $\mu\textrm{m}$, 0.32 $\mu\textrm{m}$, 10nm). The effects of particle size on gel-casting process and green microstructure were investigated. The optimum dispersion conditions using ammonium salt (D-3019) as dispersant were 0.2 wt% (4.63 $\mu\textrm{m}$), 0.5 wt% (0.32 $\mu\textrm{m}$), and 5.0 wt% (10 nm), in high solid loading. The optimum solid loading of each starting material for gel-casting was obtained as 59 vol% (4.63 $\mu\textrm{m}$), 57 vol% (0.32 $\mu\textrm{m}$), 15 vol% (10 nm), depending on particle size, indicating that nano-size particle (10 nm) represent lower solid loading as high specific surface area than those of other two starting materials. The drying at ambient conditions (humidity; $\thickapprox$90%) was performed more than 48hrs to enable ejection of the part from the mold and then at $120^{\circ}C$ for 2hrs in an air oven, showing no crack and flaw in the dried green bodies. The pore size and distribution of the gelcast green bodies showed the significant decrease with decreasing particle size. Green microstructure was dependent on the pore size and distribution due to the particle size, and on the deairing step. The green density maximum obtained was 58.9% (4.63 $\mu\textrm{m}$), 60% (0.32 $\mu\textrm{m}$), 47% (10 nm) theoretical density (TD), and the deairing step applied before gel-casting did not affect green density.

• Preventive Nutrition and Food Science
• /
• v.6 no.2
• /
• pp.126-132
• /
• 2001

Methanol extracts form four kinds of kimchi, which were differently prepared in kinds and levels of sub-ingredients, were given to Balb/c mice for 3 weeks (0.5 mg/kg/day). Peritoneal macrophages isolated from mice treated with kimchi extracts and saline were stimulated by lipopolysaccharide (LPS). K3 and K4 kimchis, containing more red pepper powder, garlic, Chinese pepper powder, mustard leaf and organically cultivated Korean cabbage, significantly increased NO production by the activated macrophages (p<0.05). K1, K2, K3 and K4 kimchi extracts (0.01, 0.1, 1.0 $\mu\textrm{g}$) significantly reduced the increased TGF-$\beta$1 production of H.pylori lysate (0.01 $\mu\textrm{g}$)-activated human epithelial RPMI 2650 cells (5$\times$10$^{4}$ cells/mL) at 24 and 48 hrs of treatment (p<0.01). However, the decreased TGF-$\beta$1 $\alpha$ production of RPMI 2650 cells by H. pylori lysate increased by treatment with kimchi extract for 72 hrs. Especially, K4 kimchi (containing organically cultivated Korean cabbage and more ingredients, modulated TGF-$\beta$1 production of H. pylori lysate-activated RPMI 2650 cells to the normal level (control) by treatment for 48 hrs. The treatment of K1 and K4 kimchi enhanced the LPS (0.01 $\mu\textrm{g}$/mL)-induced IL-6 production of splenocytes. The results suggest that kimchi might have an beneficial effect on cancer prevention due in part to the function enhancing NO production of activated macrophages. Our data suggest that kimchi could modulate TGF-$\beta$1 production by cancer cells and IL-6 production of splenocytes, thereby possibly contributing to control carcinogenesis and the immune system.