• Environmental Analysis Health and Toxicology
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• v.31
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• pp.1.1-1.13
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• 2016

Objectives To investigate the accuracy and scientific validity of the current very low risk factor for hereditary diseases in humans following exposures to ionizing radiation adopted by the United Nations Scientific Committee on the Effects of Atomic Radiation and the International Commission on Radiological Protection. The value is based on experiments on mice due to reportedly absent effects in the Japanese atomic bomb (A-bomb) survivors. Methods To review the published evidence for heritable effects after ionising radiation exposures particularly, but not restricted to, populations exposed to contamination from the Chernobyl accident and from atmospheric nuclear test fallout. To make a compilation of findings about early deaths, congenital malformations, Down's syndrome, cancer and other genetic effects observed in humans after the exposure of the parents. To also examine more closely the evidence from the Japanese A-bomb epidemiology and discuss its scientific validity. Results Nearly all types of hereditary defects were found at doses as low as one to 10 mSv. We discuss the clash between the current risk model and these observations on the basis of biological mechanism and assumptions about linear relationships between dose and effect in neonatal and foetal epidemiology. The evidence supports a dose response relationship which is non-linear and is either biphasic or supralinear (hogs-back) and largely either saturates or falls above 10 mSv. Conclusions We conclude that the current risk model for heritable effects of radiation is unsafe. The dose response relationship is non-linear with the greatest effects at the lowest doses. Using Chernobyl data we derive an excess relative risk for all malformations of 1.0 per 10 mSv cumulative dose. The safety of the Japanese A-bomb epidemiology is argued to be both scientifically and philosophically questionable owing to errors in the choice of control groups, omission of internal exposure effects and assumptions about linear dose response.

• International Journal of Aeronautical and Space Sciences
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• v.17 no.3
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• pp.409-422
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• 2016

A parametric study based on an unsteady mathematical model of a pyrotechnically actuated device was performed for design optimization. The model simulates time histories for the chamber pressure, temperature, mass transfer and pin motion. It is validated through a comparison with experimentally measured pressure and pin displacement. Parametric analyses were conducted to observe the detailed effects of the design parameters using a validated performance analysis code. The detailed effects of the design variables on the performance were evaluated using the one-at-a-time (OAT) method, while the scatter plot method was used to evaluate relative sensitivity. Finally, the design optimization was conducted by employing a genetic algorithm (GA). Six major design parameters for the GA were chosen based on the results of the sensitivity analysis. A fitness function was suggested, which included the following targets: minimum explosive mass for the uniform ignition (small deviation), light casing weight, short operational time, allowable pyrotechnic shock force and finally the designated pin kinetic energy. The propellant mass and cross-sectional area were the first and the second most sensitive parameters, which significantly affected the pin's kinetic energy. Even though the peak chamber pressure decreased, the pin kinetic energy maintained its designated value because the widened pin cross-sectional area induced enough force at low pressure.

• Membrane and Water Treatment
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• v.9 no.5
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• pp.363-371
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• 2018

In this work, it was investigated the usability of artificial bee colony (ABC) and genetic algorithm (GA) in modeling adsorption of Co(II) onto drinking water treatment sludge (DWTS). DWTS, obtained as inevitable byproduct at the end of drinking water treatment stages, was used as an adsorbent without any physical or chemical pre-treatment in the adsorption experiments. Firstly, DWTS was characterized employing various analytical procedures such as elemental, FT-IR, SEM-EDS, XRD, XRF and TGA/DTA analysis. Then, adsorption experiments were carried out in a batch system and DWTS's Co(II) removal potential was modelled via ABC and GA methods considering the effects of certain experimental parameters (initial pH, contact time, initial Co(II) concentration, DWTS dosage) called as the input parameters. The accuracy of ABC and GA method was determined and these methods were applied to four different functions: quadratic, exponential, linear and power. Some statistical indices (sum square error, root mean square error, mean absolute error, average relative error, and determination coefficient) were used to evaluate the performance of these models. The ABC and GA method with quadratic forms obtained better prediction. As a result, it was shown ABC and GA can be used optimization of the regression function coefficients in modeling adsorption experiments.

• Journal of Plant Biology
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• v.39 no.4
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• pp.273-278
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• 1996

Arabidopsis mutants deficient in flavonoid and sinapate ester (tt4 and fah1-7, respectively) were evaluated in vivo and in vitro to study the possible role of flavonoid compounds in pollen tube growth. In vivo, we investigated pollen tube growth in the pistils of the mutants and wild type(Ler). The growth of pollen tubes was significantly different among the three genotypes. In the fal1-7 pistils, the tubes grew to a greater length relative to those of the wild type or tt4. To examine in vitro pollen tube growth, a solid medium was devised for pollen germination and subsequent growth. In vitro, the identical result was obtained; fahl-7 pollens developed the longest tubes and elongated most rapidly. Therefore, the growth response of pollen tubes to phenolic compounds was examined by adding quercetin or sinapate ester in various concentrations to the media. Quercetin enhanced both germination rate and tube growth in the pollens of the mutants and the wild type, especially in tt4. In contrast, sinapate ester inhibits pollen germination and pollen tube growth in three genotypes. These results suggest that flavonoids and related phenolic compounds have physiological role in the plant reproductive system.

• Journal of Bio-Environment Control
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• v.13 no.4
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• pp.209-216
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• 2004

This study was aimed to assess the effects of microclimate factors on lettuce chlorophyll fluorescent responses and to develop an environment control system for plant growth by adopting a simple genetic algorithm. The photosynthetic responses measurements were repeated by changing one factor among six climatic factors at a time. The maximum Fv'/Fm' resulted when the ambient temperature was $21^{\circ}C,\;CO_2$ concentration range of 1,200 to 1,400 ppm, relative humidity of $68\%$, air current speed of $1.4m{\cdot}s^{-1}$, and the temperature of nutrient solution of $20^{\circ}C$. In PPF greater than $140{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, Fv'/Fm' values were decreased. To estimate the effects of combined microclimate factors on plant growth, a photosynthesis efficiency model was developed using principle component analysis for six microclimate factors. Predicted Fv'/Fm' values showed a good agreement to measured ones with an average error of $2.5\%$. In this study, a simple genetic algorithm was applied to the photosynthesis efficiency model for optimal environmental condition for lettuce growth. Air emperature of $22^{\circ}C$, root zone temperature of $19^{\circ}C,\;CO_2$ concentration of 1,400 ppm, air current speed of $1.0m{\cdot}s^{-1}$, PPF of $430{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, and relative humidity of $65\%$ were obtained. It is feasible to control plant environment optimally in response to microclimate changes by using photosynthesis efficiency model combined with genetic algorithm.

• The Korean Journal of Food And Nutrition
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• v.33 no.1
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• pp.17-26
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• 2020

This study was conducted to evaluate the functionality of fermented black garlic extracts under various conditions. Black garlic powder was prepared by aging for 0~72 hours at 80℃ depending on relative humidity (RH). It showed the highest antioxidant effects among the samples; the total antioxidant activity of black garlic powders at RH 75%, 84%, and 90% for 72 hours was increased 31.9 times, 28.2 times, and 22.6 times compared with that of the fresh garlic powder, respectively. Also, the alliin content was gradually decreased. S-ally-L-cysteine and S-ethyl-cysteine levels were increased; the highest values were 495.9 ㎍/g and 1,769.7 ㎍/g after aging for 72 hours at RH 75%. Aspartate transaminase (AST) and alanine transaminase (ALT) levels were increased following high fat diet feeding, but the rise was obviously reduced by administration of black garlic extract. The total cholesterol, LDL/VLDL-cholesterol, and triglyceride contents in serum were significantly lower in methionine and choline deficient (MCD) diet treatment groups than in the positive control group. The concentration was increased following the intake of black garlic and fermented black garlic extracts. Therefore, black garlic extracts could be an ideal material as a dietary supplement in healthy functional foods to improve the effects on fatty liver.

• Korean Journal of Biological Psychiatry
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• v.11 no.2
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• pp.146-154
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• 2004

Objective:Attention deficit hyperactivity disorder(ADHD) is the most common childhood psychiatric disorder, affecting 3-5% of school-aged children. Although the biological basis of ADHD is unknown, family studies provide strong evidence that ADHD has a genetic basis. Recent genetic studies have suggested associations between ADHD and serotonin 1B(5HT1B) receptor gene G861C polymorphism. The aim of this study is to test for the association between ADHD and 5HT1B receptor gene G861C polymorphism in Korean population. Method:We processed DNA extraction and genotyping. 106 Korean children with ADHD and their parents were analyzed using the transmission disequilibrium test(TDT) and haplotype-based haplotype relative risk (HHRR). And the ADHD children were compared with 212 age and gender matched normal controls. Results:There was no statistical difference of distributions between ADHD cases and controls. We did not observe any preferential transmission of alleles of 5HT1B receptor gene G861C polymorphism in ADHD. Conclusions:Though there is the possibility of failing to detect small genetic effects, our results show no evidence of an association between ADHD and 5HT1B receptor gene G861C polymorphism in the Korean population and indicate that it is unlikely that the 5HT1B receptor is implicated in the susceptibility to ADHD.

• Journal of Plant Biotechnology
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• v.43 no.3
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• pp.332-340
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• 2016

Seed size traits are controlled by multiple genes in crops and determine grain yield, quality and appearance. However, the molecular mechanisms controlling the size of plant seeds remain unclear. We performed functional analysis of BrPATL4 encoding Sec14-like protein to determine the genetic architecture of seed size, shape and their association analyses. We used 60 $T_3$ transgenic rice lines to evaluate seed length, seed width and seed height as seed size traits, and the ratios of these values as seed shape traits. Pleiotropic effects on general architecture included small seed size, erect panicles, decreased grain weight, reduced plant height and increased sterility, which are common to other mutants deficient in gibberellic acid (GA) biosynthesis. To test whether BrPATL4 overexpression is deleterious for GA signal transduction, we compared the relative expression of GA related gene and the growth rate of second leaf sheath supplied with exogenous $GA_3$. Overexpression of BrPATL4 did not affect GA biosynthesis or signaling pathway, with the same response shown under GA treatment compared to the wild type. However, the causal genes for the small seed phenotype (D1, SRS1, and SRS5) and the erection of panicles showed significantly decreased levels in mRNA accumulation compared to the wild type. These results suggest that the overexpression of BrPATL4 can control seed size through the suppression of those genes related to seed size regulation. Although the molecular function of BrPATL4 is not clear for small seed and erect panicles of BrPALT4 overexpression line, this study provides some clues about the genetic engineering of rice seed architecture.

• Korean Journal of Plant Resources
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• v.19 no.1
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• pp.97-104
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• 2006

This study was conducted to investigate effect of temperature and NaCl on the seed germination and water absorption of Thuja orientalis. Seeds were treated with 0, 500, 1,000, 2,000 and 4,000ppm of NaCl and placed in different chambers at 15, 20, 25 and $30^{\circ}C$, respectively. And seed properties and relative water absorptions were analyzed. Germination decreased with the increase of both temperature and NaCl concentration, and especially the difference was obvious at $30^{\circ}C$. Dormancy and mortality increased with the increase of temperature in non-NaCl treatment. Two-way analysis of variance showed significant effects of temperature, NaCl concentration and interaction between temperature and NaCl concentration (p<0.001). Mean germination time increased with the increase of NaCl concentration at 15, 20 and $25^{\circ}C$ but decreased at $30^{\circ}C$ because the seeds were mortal by NaCl high concentration, Germination speed and germination performance index decreased with the increase of NaCl concentration. Those represented decreasing tendency with NaCl concentration but high positive correlation with germination. Relative water absorption decreased with the increase of NaCl concentration and represented high values at $15^{\circ}C$, and showed high positive correlations with germination, germination speed and germination performance index. It was reported that the high temperature and salinity were inhibitive factors of seed germination of Thuja orientalis.

• Korean Journal of Plant Resources
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• v.19 no.5
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• pp.580-585
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• 2006

This experiment was conducted to study the effects of sulphuric acid, cutting, cold stratification and hot water on the germination of Sophora japonica seeds, which have difficulty to germinate because they have hard and thick seed coats. The seeds were immersed in 30, 60 and 90% sulphuric acid for 30 minutes as seed scarifications, and cut 1/8, 2/8 and 3/8 of the opposite parts of radicles. As cold stratification the seeds were wrapped in wet towel, and then stored in plastic bags in a refrigerator $(4^{\circ}C)$ for 3, 5 and 10 days. The seeds were immersed in hot water $(90{\sim}95^{\circ}C)$ for 2,5 and 10 minutes. Pretreated seeds represented different germination properties, respectively. After sulphuric acid treatment, the seeds showed an increase in germination (G) and germination index (GI). Compared to the other treatments, 90% sulphuric acid showed the highest G (31.7%) and GI (6.2). The G and GI of cut seeds decreased with the increase of seed cutting lengths. And G and GI of cold stratificated seeds were not significantly different among the days treated (p=0.258). Two minutes treatment of hot water showed lower G and Gl than control, and the seeds were not germinated in 5 and 10 minutes treatments of hot water. At the result of relative growth rate and T/R ratio of seedlings from pretreated seeds, the seedlings from seeds in 90% sulphuric acid treatment represented the highest relative growth rate and T/R ratio.