• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.7
• /
• pp.3123-3127
• /
• 2012

Objective: Experimental studies have suggested green tea to be a chemopreventive agent for colorectal cancer, and many studies have examined possible associations. However, the conclusions were inconsistent or even contradictory, so we performed a meta-analysis based on published case-control studies to explore if green tea is indeed a protective factor. Methods: PubMed was searched up to May $10^{th}$, 2012 for relevant studies, and references of included studies were manually searched. Finally 13 eligible studies, involving 12,636 cases and 38,419 controls were identified. After data extraction, a meta-analysis was performed using CMA v2 software. Results: The results indicated there may be a weak but not statistically significant reduced risk of colorectal cancer with high dose of green tea intake (OR=0.95, 95% CI:0.81-1.11, p=0.490.69-0.98). This protective effect was also found in all subgroups, except in American and European populations. Sensitivity analysis indicated the result to be robust. Publication bias was not detected by either funnel plot or Egger tests. Conclusion: The results of this meta-analysis indicate a weak lower tendency for colorectal cancer development with green tea consumption, but available epidemiologic data are insufficient to conclude that green tea may protect against colorectal cancer in humans.

• Journal of Mushroom
• /
• v.15 no.1
• /
• pp.57-60
• /
• 2017

In this study, we attempted to find alternative materials to rice bran (Japonica in Korea) such as rice bran pellet (Indica in Pakistan), corn distillers dried grains with solubles, sesame oil meal, and kapok meal for bottle cultivation of Pleurotus eryngii. Among all treatments, the total carbon content of the mixed substrate was the highest in T1 and the total nitrogen content was the highest in T4. The C/N ratio of T2 was comparable to that of the control and was higher than that of other treatments. The diameter of the pileus was the largest in T1 and T2, and the length of the stipe was the largest in T1 and T2. The yield and bio-efficiency of the fruit body were higher in T2 than in the other treatments, and were similar to that of the control plot. Therefore, the findings of our study suggest that rice bran pellet (Indica in Pakistan) could be a suitable alternative to rice bran (Japonica in Korea) for the cultivation of P. eryngii.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.12
• /
• pp.15-20
• /
• 1972

There are still many problems on the physiological role of silicon in rice plants, although, it has been reported that silicate slag is the most effective fertilizer for the improvement of Akiochi soils. This experiment is carried out to investigate the effect of silicate of the mineral nutrition uptake by rice plants, using Ca45, P32, C136, and Mn54. The obtained results are summerized as follows; 1. Contents of mineral nutrients except silicon were higher in the rice plant grown in minus Si-culture solution a than in plus Si-plot. 2. Transpiration amounts appeared to be greater in the low content plant of silicon. 3. The rate of translocation to shoot of each ion absorbed by roots depended on the rate of transpiration. 4. It seemed that only CI uptake was found small in minus Si-root. 5. Silicate fetilizer did not affect the solubility of mineral ions in soils.

• Journal of Biomedical Engineering Research
• /
• v.37 no.2
• /
• pp.61-67
• /
• 2016

This paper presented a method for random forest based the arrhythmia classification using both heart rate (HR) and heart rate variability (HRV) features. We analyzed the MIT-BIH arrhythmia database which contains half-hour ECG recorded from 48 subjects. This study included not only the linear features but also non-linear features for the improvement of classification performance. We classified abnormal ECG using mean_NN (mean of heart rate), SD1/SD2 (geometrical feature of poincare HRV plot), SE (spectral entropy), pNN100 (percentage of a heart rate longer than 100 ms) affecting accurate classification among combined of linear and nonlinear features. We compared our proposed method with Neural Networks to evaluate the accuracy of the algorithm. When we used the features extracted from the HRV as an input variable for classifier, random forest used only the most contributed variable for classification unlike the neural networks. The characteristics of random forest enable the dimensionality reduction of the input variables, increase a efficiency of classifier and can be obtained faster, 11.1% higher accuracy than the neural networks.

• Journal of Photoscience
• /
• v.4 no.3
• /
• pp.97-103
• /
• 1997

The effect of temperature on the fluorescence quenching of 2-(4-Methoxyphenyl)-5-(1-naphthyl)-1,3,4-oxadiazole (MPNO1), 2-(4-Methoxyphenyl)-5-(2-naphthyl)-1,3,4-oxadiazote(MPNO2), by aniline, and 2-Phenylindole (2-PI) by CCk, in toluene by steady state method and in benzene by time-resolved method have been carried out in the temperature range 30 - 70$\circ$C. The Stem-Volmer (S-V) plots, I$_0$/I against quencher concentration [Q] at different temperanares show positive deviations. The fluorescence lifetimes determined at different temperatures show no systematic variations and the variations being within the experimental error, the average values of lifetimes $ $\tau$ (t) are taken for further calculations. Rate constants such as Stem-Volmer quenching constants K$_sv}$, quenching rate parameters k$_q$ and k'$_q$, static quenching constant V and kinetic distance r are determined using the modified Stem-Volmer equation and sphere of action static quenching model. In order to see whether the reactions are diffusion limited, equations k$_q$ = e$^{-Eq/RT}$ and k'$_q$ = e$^{-Eq/RT}$ are used to determine the values of E$_q$ and E'$_q$, the activation energies for collisional quenching and the values of E$_q$ are 14.53. 17.28 and 16.20 kJ mole$^{-1}$ for MPNO1, MPNO2 and 2-PI respectively and the values of E'$_q$ are 14.62 and 17.73 for MPNO1 and MPNO2 respectively. From the magnitudes of various quantities it has been concluded that the reactions are diffusion limited and the observed positive deviations in the S-V plot are due to static and dynamic quenching.

• Journal of Preventive Medicine and Public Health
• /
• v.46 no.1
• /
• pp.10-18
• /
• 2013

Objectives: We investigated the association between particulate matter less than $10{\mu}m$ in aerodynamic diameter ($PM_{10}$) exposure and non-accidental mortality in Asian populations by meta-analysis, using both time-series and case-crossover analysis. Methods: Among the 819 published studies searched from PubMed and EMBASE using key words related to $PM_{10}$ exposure and non-accidental mortality in Asian countries, 8 time-series and 4 case-crossover studies were selected for meta-analysis after exclusion by selection criteria. We obtained the relative risk (RR) and 95% confidence intervals (CI) of non-accidental mortality per $10{\mu}g/m^3$ increase of daily $PM_{10}$ from each study. We used Q statistics to test the heterogeneity of the results among the different studies and evaluated for publication bias using Begg funnel plot and Egger test. Results: Testing for heterogeneity showed significance (p<0.001); thus, we applied a random-effects model. RR (95% CI) per $10{\mu}g/m^3$ increase of daily $PM_{10}$ for both the time-series and case-crossover studies combined, time-series studies relative risk only, and case-crossover studies only, were 1.0047 (1.0033 to 1.0062), 1.0057 (1.0029 to 1.0086), and 1.0027 (1.0010 to 1.0043), respectively. The non-significant Egger test suggested that this analysis was not likely to have a publication bias. Conclusions: We found a significant positive association between $PM_{10}$ exposure and non-accidental mortality among Asian populations. Continued investigations are encouraged to contribute to the health impact assessment and public health management of air pollution in Asian countries.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.16 no.2
• /
• pp.161-168
• /
• 1996

This experiment was canied out to determine the effect of cultivar, harvest date and drying method on the changes of moisture content and quality of spring harvest oat(Avena sativa L.) hay. Disign of the experiment was a spilt-split-plot arrangement with early and late cultivars as main plots, early and late harvest dates as sub-plots, and drying agent and tedding as sub-subplots in three replications. Moisture content of early harvest oat was higher than that of late harvest oat by 127.1% dry weight(DW) in 'Swan' and 39.8%DW in 'Foothill'. Moisture content difference between 'Foothill' and 'Swan' was 117.6%DW at early and 204.9%DW at late harvest dates, respectively. Cultivar effect on moisture content of cut oat was higher at late harvest date, but drying method effect was higher at early harvest. Total nitrogen content of early harvest was higher than that of late harvest by 0.70% and that of 'Foothill' was higher than that of 'Swon' by 0.86%. But no difference in total nitrogen content was found between the drying method. ADF and NDF contents were increased at late harvest by 29% and 1 I%, respectively(P<0.05). ADF and NDF contents of 'Swan' were higher than those of 'Foothill' by 2.8% and 4.5%, respectively. No difference in ADF and NDF contents was obtained by drying methods. RFV of early harvest oat hay was 95.1 and 103.8 for 'Swan' and 'Foothill' but late harvest 'Swan' and 'Foothill' showed 74.8 and 85.0, respectively.

• Archives of Pharmacal Research
• /
• v.28 no.8
• /
• pp.923-929
• /
• 2005

Methanol extracts of domestic plants of Korea were evaluated as a potential inhibitor of neutral pH optimum and membrane-associated 60 kDa sphingomyelinase (N-SMase) activity. In this study, we partially purified N-SMase from bovine brain membranes using ammonium sulfate. It was purified approximately 163-fold by the sequential use of DE52, Butyl-Toyopearl, DEAE-Cellulose, and Phenyl-5PW column chromatographies. The purified N-SMase activity was assayed in the presence of the plant extracts of three hundreds species. Based on the in vitro assay, three plant extracts significantly inhibited the N-SMase activity in a time- and concentration-dependent manner. To further examine the inhibitory pattern, a Dixon plot was constructed for each of the plant extracts. The extracts of Abies nephrolepis, Acer tegmentosum, and Ginkgo biloba revealed a competitive inhibition with the inhibition constant (Ki) of $11.9 {\mu}g/mL,\;9.4{\mu}g/mL,\;and\;12.9{\mu}g/mL$, respectively. These extracts also inhibited in a dose-dependent manner the production of ceramide induced by serum deprivation in human neuroblastoma cell line SH-SY5Y.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2011.08a
• /
• pp.333-333
• /
• 2011

We have investigated the breakdown properties in liquids by high voltage pulse system. High voltage pulse power system is consisted of the Marx-generator with two capacitors (0.5 ${\mu}F$, withstanding voltage is 40 kV), to which the charging voltage can be applied to maximum 30 kV DC, spark gap switch and charging resistor of 20 $M{\Omega}$. We have made use of tungsten pin electrodes of anode-cathode (A-K), which are immersed into the liquids. The breakdown voltage and current signals are measured by high voltage probe (Tektronix P6015A) and current monitor (IPC CM-1.S). Especially the high speed breakdown or plasma propagation characteristics in the pulsed A-K gap have been investigated by using the high speed ICCD camera. We have measured the electron temperature through the Boltzmann plot method from the breakdown spectrums. Here the A-K gap has been changed by 1 mm, 2 mm, and 3 mm. The used liquids are distilled water and solution of salt (0.9 %). The output voltage and current signals at breakdown in distilled water are shown to be bigger than those in saline solution. The breakdown voltage and current characteristics in liquids will be discussed in accordance with A-K gap distances. It is also found that the electron temperatures and plasma densities in liquids are decreased in conformity with A-K gap.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.9 no.3
• /
• pp.153-157
• /
• 1989

This experiment was carried out to investigate the effects of the first harvesting times and regrowth periods after the fist harvest on grass regrowth, dry matter (DM) yield and botanical composition in pasture mixtures during 1987 and 1988. For the test, a split plot design with 3 replications was treated with 3 different first harvesting times (vegetative, stem elongation and heading stage) and 3 different regrowth periods (20, 30 and 40 days) after first harvest. Although the total DM yield of grasses was decreased slightly with earlier cutting, the regrowth DM yield and the regrowth plant height was increased significantly with earlier cutting (p < 0.05). Also, the 30 days of regrowth periods was contributed greatly to the regrowth and the DM yield. The percentage of legumes Tmainly red clover) in botanical composition was increased with later initial harvest anrl longer regrowth period after first harvest. Based on the results, it is suggested that good grass regrowth and seasonal distribution could be achieved by the earlier harvest at fist and the regrowth period of 30 days after first harvest in spring.