• Korean journal of applied entomology
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• v.54 no.2
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• pp.73-81
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• 2015

A Cohort based model for temperature-dependent population dynacmics of Riptortus pedestris was constructed by using a commercial software (DYMEX) and seasonal occurrence along with pesticide treatments effect was simulated and validated with pheromone trap data. Ten modules of DYMEX software were used to construct the model and Lifecycle module was consisted of seven developmental stages (egg, 1 - 5 nymphal instars, and adult) of R. pedestirs. Simulated peaks of adult populations occurred three or four times after the peak of overwintered populations which was similar to those observed from pheromone trap catch. Estimated dates for the second peak were quite similar (1-2 day difference) with those observed with pheromone trap. However, the estimated dates for the first population peak were 9-16 days later than the observed dates by pheromone trap and the estimated dates for the last peak were 17-23 days earlier than the observed dates. When insecticide treatments were included in the simulation, the biggest decrease in R. pedestris adult density occurred when insecticide was applied on July 1 for the first peak population: the estimated adult density of the second peak was 3% of untreated population density. When insecticide was assumed to be applied on August 30 for the second peak population, the estimated adult density of the following generation was about 25% of untreated population and the peak density of the following generation reached about two weeks later than untreated population. These results can be used for the efficient management strategies for the populations of R. pedestris.

• Journal of Sericultural and Entomological Science
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• v.51 no.2
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• pp.99-106
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• 2013

The purpose of this study is to investigate the effects of supplementation of mulberry powder, mulberry extract and silkworm powder during the 8 weeks of resistance exercise on Androgen receptor(AR) mRNA and Myogenic regulatory factors(MRFs) expression of rats muscle. Fifty males, Sprague-Dawley rat, were randomly divided into 5 groups: CON(control group, n = 10), REG(resistance exercise group, n = 10), MP REG(mulberry powder intake and resistance exercise group, n = 10), ME REG(mulberry extract intake and resistance exercise group, n = 10) and SP REG(silkworm powder intake and resistance exercise group, n = 10). After climbing the ladder without weights during the 1 week of adaptation period, the rats in the resistance exercise group were trained to climb a 0.98-m vertical(80 degree incline) ladder with weights in their tail during 7 weeks(10 times each day, 2 days per week). After exercise, the skeletal muscle was extracted from the flexor hallucis longus. After separating the total ribonucleic acid (RNA) of each group, quantitative polymerase chain reaction was used to analyze RNA quantitatively. AR mRNA and MRFs expression revealed that all of the treated groups had significantly difference. AR mRNA expression increased in ME REG $6.24{\pm}1.85$ and SP REG $9.68{\pm}0.28$ fold compared to CON. Myod mRNA expression increased in MP REG $6.04{\pm}0.47$, ME REG $4.31{\pm}1.58$ and SP REG $8.11{\pm}0.57$ fold compared to CON. And myogenin mRNA expression increased in MP REG $4.11{\pm}0.42$, ME REG $4.12{\pm}0.45$ and SP REG $6.50{\pm}0.61$ fold compared to CON. In conclusion, during the resistance exercise, providing mulberry and silkworm gives positive effect on AR mRNA and MRFs expression increase.

• Korean Journal of Agricultural Science
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• v.28 no.1
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• pp.33-40
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• 2001

The authors attempted to derive a comprehensive quantitative structure-toxicity relationships (QSTRs) between various physicochemical parameters of phenyl substituents in fungicidal phenylthionocarbamate derivatives and toxicity evaluated using TOPKAT calculation. On the basis of this approach we made preditions for toxicity values for not yet tested substances with respect to these systems. The results suggested that the optimal values, $(B_2)_{opt.}=1.54_{\AA}$(Ames mutagenicity), $(R)_{opt.}=0.16$ (car-cinogenicity of male rat), $(\pi)_{opt.)=0.16$ (carcinogenicity of male mouse), $({\varepsilon}LOMO)_{opt}=-0.52e.v.$ ($LD_{50}$ of rat oral), $(B_3){opt.}=1.54_{\AA}$(chronic LOAEU), $(logP)_{opt.}=4.25$ ($LC_{50}$ of Fathead minnow) and $({\sigma})_{opt}=-0.68$ ($EC_{50}$ of Daphnia magna) of phenyl substituents were strongly correlated with the acute and chronic toxicities.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.1
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• pp.29-41
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• 2019

Terrestrial Gross Primary Production (GPP) is the largest global carbon flux, and forest ecosystems are important because of the ability to store much more significant amounts of carbon than other terrestrial ecosystems. There have been several attempts to estimate GPP using mechanism-based models. However, mechanism-based models including biological, chemical, and physical processes are limited due to a lack of flexibility in predicting non-stationary ecological processes, which are caused by a local and global change. Instead mechanism-free methods are strongly recommended to estimate nonlinear dynamics that occur in nature like GPP. Therefore, we used the mechanism-free machine learning techniques to estimate the daily GPP. In this study, support vector machine (SVM), random forest (RF) and artificial neural network (ANN) were used and compared with the traditional multiple linear regression model (LM). MODIS products and meteorological parameters from eddy covariance data were employed to train the machine learning and LM models from 2006 to 2013. GPP prediction models were compared with daily GPP from eddy covariance measurement in a deciduous forest in South Korea in 2014 and 2015. Statistical analysis including correlation coefficient (R), root mean square error (RMSE) and mean squared error (MSE) were used to evaluate the performance of models. In general, the models from machine-learning algorithms (R = 0.85 - 0.93, MSE = 1.00 - 2.05, p < 0.001) showed better performance than linear regression model (R = 0.82 - 0.92, MSE = 1.24 - 2.45, p < 0.001). These results provide insight into high predictability and the possibility of expansion through the use of the mechanism-free machine-learning models and remote sensing for predicting non-stationary ecological processes such as seasonal GPP.

• Journal of Animal Environmental Science
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• v.11 no.2
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• pp.135-146
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• 2005

This study was carried out to investigate the effect of Synechocystis sp. KACC 91007 when added to a pig slurry or pig liquid fertilizer (PLF) on germination index (GI) of Chinese cabbage. The preliminary experiment involved the screening of inoculant levels which were; 0.05, 0.1, 0.2, and $0.3\%$, respectively. The $0.05\%$ level of inoculant was selected based on low phytotoxicity and high GI.. The PLF underwent a 107 day aerobic and anoxic processing conditions. The T-N, T-P, $NH_4$, and $NO_3-N$ concentrations of the untreated pig slurry were; 2,873, 753, 1,441.6, and 16.48 ppm, respectively. Using aerobic processing treatment, the fertilizer value of the PLF was 3,672, 164, 183.87, and 21.97 ppm, respectively. In contrast, the fertilizer value of the PLF processed under anoxic condition was reduced to 1,261, 68, 161, and 16.87 ppm. The GI value of the untreated PLF under aerobic and anoxic processing condition was 83 and $40.4^{*}\%$, respectively. With the addition of the $0.05\%$ microbial inoculant, the GI improved by more than 40 and $50\%$ respectively, when the PLF was processed under anoxic and aerobic conditions. The above findings proved that the aerobic processing of PLF for 107 days was better than anoxic and yielded higher T-N which is a macro-nutrient fertilizer material. Consequently, the addition of $0.05\%$ microbial inoculant resulted to a higher GI of the Chinese cabbage specifically under aerobic processing condition.

• Journal of environmental and Sanitary engineering
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• v.5 no.1
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• pp.54-62
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• 1990

The recovery of vegetatiion and soil properties in the burned fields after forest fire were studied in Chung Cheong Buk Do area, Korea, from July 23 to 28, 1981. Miscanthus sinensis var. purpurascens, Carex humilis and Lespedeza bicolor were dominant species in the burned field of the second year after forest fire as well as unburned field. Especially, Lespedeza bicolor was gradually grown to the dominant species. Lespedeza bicolor, Carex humilis and Miscanthus sinensis var. purpurascens were the dominant species in the burned field of the fifth year after forest fire. Biological spectra of the burned fields were similar to the umburned fields with $H-e-D_1-R_5$ or $Ph-e-D_1-R_5$ from the second year after forest fire. Accordingly, biological spectra were recovered to the unburned fields from the second year. Degree of successiion was DS=423 in the burned field and DS=524 in the unburned field in 1981. The DS of the burned fields was gradually increased and recovered to be similar to the unburned from the second year. In the species diversities and evenness index, H,e and $\beta$ of the burned field in 1981 were higher and $\lambda$ was lower than the unburned field, but all of the indices were recovered to the unburned field from the second or third years. Accordingly, the vegetation of the first year was the complex community in view floristic composition, but it was recovered to the simple community as unburned field fromthe second or third years. In the soil preperties, pH, total nitrogen, available phosphorus, exchangeable potassium, exchangeable calcium and exchangeable magnesium were increased and organic matter was decreased due to forest fire, and then was recovered to the unburned field from the second or third years. The vegetation and soil properties of the burned field after forest fire were similary recovered to the unburned field from the second or third years. Accordingly, there was a close relationship between the trend of vegetation recovery and the changes of soil characteristics after forest fire.

• Journal of Dairy Science and Biotechnology
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• v.24 no.1
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• pp.9-18
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• 2006

Total 150 packs of UHT milk and UHT-ESL milk, produced by different domestic milk companies, were compared at refrigerated and room temperature for 35 days in terms of microbiological qualities such as incidence date, number of incidence packs, and numbers of bacteria, and post-pasteurization contamination. Overall qualities of UHT-ESL milk were slightly better than that of UHT milk in relations to total bacteria in milk. No coliforms were detected in two groups of UHT milk samples after 35 days. Aerobic spores were more common in two brands of UHT milks stored in 20$^{\circ}$C than those in 7$^{\circ}$C, in which spores were broken out at 7 and 14 day. No incidences of thermoduric bacteria were founded until 14 days in two groups of UHT milks, but high level of counts (<300${\sim}$<3,000 CFU/ml) after 21 days at 20$^{\circ}$C and 40${\sim}$3,600 CFU/ml at 7$^{\circ}$C were detected, respectively. Psychrotrophic bacteria were higher in UHT milk than in UHT-ESL milk, in which began to detect at 28 days. No post-pasteurization contamination by salmonella spp. and staphylococcus aureus were found throughout the experimental periods. One may conclude that the shelf life of UHT milk under cold-chains system can be extended up to 21days, as long as UHT treated milk are filled in sterilized containers by aseptic packaging system.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.6
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• pp.873-882
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• 2008

Eight ileally cannulated pigs (BW $35.9{\pm}0.9kg$) were randomly allotted according to a $4{\times}3$ Latin square design to determine the effects of cellulose, pectin and starch on standardized ileal digestibility (SID) and apparent total tract digestibility (ATTD) of crude protein (CP) and amino acids (AA) as well as on the bacterial AA contribution in feces. The pigs were fed the control diet (20.2% CP, % dry matter (DM)) or one of the three experimental diets in which 25% of the control diet was substituted by cellulose, starch or pectin. Due to this substitution, dietary CP levels were lower in the cellulose (15.5% CP, % DM), pectin (15.4% CP, % DM) and starch diet (15.2% CP, % DM). Following a 15-d adaptation period, feces were collected for 5 d and ileal digesta for a total of 24 h. Starch increased SID of CP, while cellulose and pectin had no significant effect on the digestibility of CP. Overall, starch supplementation resulted in higher (p<0.05) SID values of histidine, isoleucine, threonine, alanine, aspartic acid, cysteine, glycine and serine compared with cellulose, while pectin decreased (p<0.05) SID of valine and proline compared with the starch and control diet. Both cellulose and pectin reduced (p<0.05) the ATTD of CP and AA, while starch decreased (p<0.05) ATTD of phenylalanine, alanine, proline and serine compared with the control. With regard to bacterial AA composition of the fecal mixed bacterial mass (MBM), cellulose supplementation increased (p<0.05) its content of N and almost all AA, except for valine, while pectin caused higher contents of arginine, histidine and proline compared with the control (p<0.05). The bacterial contribution of arginine in feces was higher (p<0.05) in the cellulose treatment, while pectin reduced (p<0.05) the bacterial contribution of leucine, alanine, glutamic acid and proline in feces compared with the control. In conclusion, the effects of cellulose, starch and pectin on SID were rather small. Bacterial activity in the large intestine can only explain the reduced ATTD values for arginine in the cellulose treatment, but not for the other AA in the cellulose and pectin treatments, suggesting higher endogenous losses of these AA in the large intestine.

• Journal of Biosystems Engineering
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• v.15 no.3
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• pp.244-256
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• 1990

This study was conducted to select the optimal machinery systems for the Mechanized Farming Groups (MFG) by their sizes. In order to achieve the objective, a survey and systems analysis were taken for 50 MFG of Chungnam province. Then a mathematical model was developed. Based on it, a computer program (MFSDINGP) was developed by the Iterative Nonlinear Goal Programming (INGP) and Hooke & Jeeves pattern search algorithm. Using MFSDINGP, optimal machinery systems were selected and presented with annual costs of machinery for the sizes of 5-40 ha of MFG.

• Molecules and Cells
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• v.20 no.3
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• pp.385-391
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• 2005

As a first step towards identifying genes involving in the signal transduction pathways mediating rice blast resistance, we isolated 3 mutants lines that showed enhanced susceptibility to rice blast KJ105 (91-033) from a T-DNA insertion library of the japonica rice cultivar, Hwayeong. Since none of the susceptible phenotypes co-segregated with the T-DNA insertion we adapted a map-based cloning strategy to isolate the gene(s) responsible for the enhanced susceptibility of the Hwayeong mutants. A genetic mapping population was produced by crossing the resistant wild type Hwayeong with the susceptible cultivar, Nagdong. Chi-square analysis of the $F_2$ segregating population indicated that resistance in Hwayeong was controlled by a single major gene that we tentatively named Pi-hy. Randomly selected susceptible plants in the $F_2$ population were used to build an initial map of Pi-hy. The SSLP marker RM2265 on chromosome 2 was closely linked to resistance. High resolution mapping using 105 $F_2$ plants revealed that the resistance gene was tightly linked, or identical, to Pib, a resistance gene with a nucleotide binding sequence and leucine-rich repeats (NB-LRR) previously isolated. Sequence analysis of the Pib locus amplified from three susceptible mutants revealed lesions within this gene, demonstrating that the Pi-hy gene is Pib. The Pib mutations in 1D-22-10-13, 1D-54-16-8, and 1C-143-16-1 were, respectively, a missense mutation in the conserved NB domain 3, a nonsense mutation in the 5th LRR, and a nonsense mutation in the C terminus following the LRRs that causes a small deletion of the C terminus. These findings provide evidence that NB domain 3 and the C terminus are required for full activity of the plant R gene. They also suggest that alterations of the resistance gene can cause major differences in pathogen specificity by affecting interactions with an avirulence factor.