• Research in Plant Disease
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• v.18 no.4
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• pp.331-337
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• 2012

Citrus melanose is one of important disease in citrus cultivation, reducing quality of citrus fruits and resulting in economic loss. Like other diseases in citrus, melanose was mainly protected by chemical fungicide in the field. Recently, alternative method of disease control is highly required due to the side effect of the chemicals. In this study four rhizobacterial strains TRH423-3, MRL408-3, THJ609-3, and TRH415-2 are selected by dual-culture testing its antifungal activity against Diaporthe citri causing citrus melanose. To investigate the protection efficacy of the selected rhizobacterial strains to citrus melanose, the bacteria were pre-treated on citrus leaves following inoculation with melanose pathogen. Pre-treatment with all selected rhizobacterial strains showed disease suppression in which the levels of protection rates were different by the rhizobacterial strains. Additional treatment with the rhizobacterial strains after the pathogen inoculation enhanced protection rates in all cases. The strain MRL408-3 and TRH423-3 were identified as Burkholderia gladioli, TRH415-2 as Pseudomons fluorescens and THJ609-3 as Pseudomonas pudia as a result of analyzing the internal transcript spaces of the rhizobacterial strains rDNA. The selected rhizobacterial strains may be valuable as biological control agents in the environment-friendly citrus farm in which chemical application is limited.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.1
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• pp.84-89
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• 1999

A simple cultivation method using Jew's mallow (Corchorus olitorius L.) was examined to evaluate the biological quality of 72 upland soils collected from greenhouses in Korea. Each soil was mixed with 4-fold volume of sterilized basal soil having no indigenous chemical and physical problems to lessen the chemical and physical variations among original sample soils. This study assumes that the biological characteristics of each mixture 2 weeks after treatment reflect those of individual sample soil prior to treatment. Jew's mallow (Corchorus olitorius L.) was cultivated for 4 weeks in a pot filled with 250g of each experimental soil and the biological quality of each soil was estimated by the aboveground plant growth. The results indicated that microbial floral quality was explicitly deteriorated in 18 soils having EC above or equal to $5dS\;m^{-1}$. However, in soils having EC below $5dS\;m^{-1}$, some showed a sign of deterioration, while others did not. As this simple method is a kind of bioassay, it dose not require the measurements of microbial numbers and activities.

• Journal of Environmental Health Sciences
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• v.41 no.6
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• pp.380-388
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• 2015

Objectives: Poisonous substances experts engage in policymaking regarding poisonous substances, whereas poisonous substances managers perform legal duties related to poisonous substances management systems at worksites. To understand and improve poisonous substances designation systems, it is necessary to distinguish the roles of these experts and managers. We further aimed to identify problems with poisonous substances appointment systems and provide basic data for their improvement by investigating the knowledge and recognition of the need for system improvement among managers and experts. Methods: To determine the $subjects^{\circ}{\emptyset}$ awareness of poisonous substances designation systems, a selfadministered questionnaire comprised of items on general characteristics and knowledge and recognition of the need for system improvement was issued. Data were analyzed via t-tests and ANOVA using SPSS v 16.0 Results: Regarding system comprehension, managers (n=213; mean 3.28, SD 0.63) significantly differed from experts (n=35; mean 4.08, SD 0.59) (P<0.001). No differences were found in recognition of need for improvement between managers (mean 3.11, SD 0.34) and experts (mean 3.24, SD 0.31). Significant differences in comprehension were found among managers by education level (P<0.05) and company size (P<0.05). Regarding industry type, comprehension was greater in the electrical/electronic and chemical/environmental industries compared to in other industries (P = 0.066). Comprehension was higher among those with five years or more of experience compared to those with less than five years. Regarding recognition of need for improvement, managers showed significant differences by company size (P<0.05). $Experts^{\circ}{\emptyset}$ comprehension showed no differences by general characteristics, while need for improvement differed according to work experience (P<0.001). Conclusion: The study found that the bigger the company size, the higher the level of comprehension by managers and the experts. In the case of both groups, where a higher comprehension of the poisonous substances designation system was evident, they recognized the necessity of its improvement.

• Journal of the Korean Chemical Society
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• v.45 no.2
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• pp.162-176
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• 2001

This study was covered with the analysis of five kinds of the middle school science text books(chemistry part) based on the oth curriculum. Particularly, inquiry activities part was analyzed by the three dimension framework which consists of inquiry content dimension, inquiry process dimension and inquiry context dimension and the results are as follows;1. In the analysis of the contents in the middle school science textbooks(chemistry part), the average number of total pages was 197.6. The illustration and picture were contained 0.66 in number per a page, and the average number of further readings was 5.8.2. In the analysis of the inquiry content dimension of inquiry activities, the total number of themes in five kinds of textbooks was 222. And the number of imquiry activities in five kinds of textbooks was siverse : A textbook had 51, B texbook 49, C textbook 37 and E textbook 35.3. For the analysis of inquiry process dimension. it follows in the order of 'interpreing data and formulating generalizations (42.4%)','observation and measuring (38.1%)','seeing a problem and seeking ways to solve it (7.8%)' and 'building, testing and revising the theoretical model(11.7%)'.4. As for the analysis of the inquiry context dimension, the scientific context occupied 94.2%, the individual context 0.4%, the social context 2.7% and the technical context 2.7%. It shows that the proportion of STS(Science-Technology-Society) related contents in inquiry activities was only 5.8%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.4
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• pp.340-360
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• 1982

Because of the continuing rapid increase in pesticide usage in Taiwan, much attention has been focus on pesticide contamination of food and effect of pesticides on human and environmental health. The Plant Protection Center (PPC) conducts safety evaluation of pesticides usee! in Taiwan. The pesticides are classified into different groups based on their acute toxicities. Pesticides which are classified into extremely toxic group are not allow to used on short term crops or the continuously harvest crops. The acute toxicity of pesticides to the beneficial insects are also studied, special attention has been paid to the two predators of rice brown planthopper. 60% of cultivated land in Taiwan are paddy field; therefore, acute fish toxicity was taken into consideration when a pesticide was applied for registration to be used in the paddy. Fish toxicities were evaluated by the dangerous rating value which is the amount of pesticide residue in the field water over the TLM value. Mutagenicity of pesticides was continuously evaluated by using Arne's microbial testing method. Island wide survey of residual levels of pesticides of known pollutants such as chlorinated hydrocarbon . insecticides, mercurial compounds in soil, water and biological samples were carried out constantly. The potential of a new1y Imported esticides to pollute the environment were studied by using model ecosystem. Ecological magnification (EM) of a chemical was calculated from model ecosystem. A chemical was considered as a pollutant when its EM value over 5000. In order to ensure the levels of pesticides residue of the crop within the safety limit. The 'tolerance' of pesticides on different crop groupings were established base on 1) acceptable daily intake value of individual pesticides, 2) average daily consumption of each crop groupings by Chinese person, 3) Actual residues of pesticides. on different crops obtained from supervised trials. Total about 79 pesticides for which the tolerances have been established on different crop groupings. Because the intensive agricultural system was adopted in Taiwan. The phytotoxicity of pesticides to the non-target crops was therefore become one of the important factor in the safety evaluation of pesticide usage. These will include 1) direct injury, 2) injury caused by pesticide polluted irrigation water, 3) injury caused by the pesticide polluted soil, 4) reduction of growth caused by the effect of pesticide on the soil microorganisms. This paper will reviewed all the aspects mentioned in the previous .paragraphs. Most the works have done in Taiwan by the PPC.y the PPC.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1612-1612
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• 2001

The production of grain for export and domestic use is one of Australia's most important agricultural industries, and the NIR technique has been used extensively over many years for the routine monitoring of grain quality, particularly moisture and protein content. Because most Australian grain is intended for human food production, the determinants of grain quality for livestock feed, apart from protein, have been largely ignored. However the increasing use of grain for feeding to pigs, poultry, beef cattle and dairy cows has led to an important national research project entitled “Premium Grains for Livestock”. Two of the objectives of this project are to determine the compositional and functional characteristics of grains which influence their nutritional quality for the various classes of livestock, and to adopt rapid and objective analytical tests for these quality criteria. NIR has been used in this project firstly to identify a set of grain samples from a large population of breeders' lines which showed a wide spectral variation, and hence a potentially wide variation in nutritional value. The selected samples were not only subjected to an extensive array of chemical, physical and in vitro analyses, but also were grown out to produce sufficient quantities of grain to feed to animals in vivo studies. Additional grains were also strategically selected from farms in order to include the effect of weather damage, such as rain, drought and frost. In this study to date, NIR calibrations have been derived or attempted, on both ground and whole grains, for in vivo dry matter digestibility (DMD), pepsin-cellulase dry matter disappearance, protein, fat, acid detergent fibre, neutral detergent fibre, starch, in sacco DMD and in vitro assays to simulate starch digestion in the lumen and small intestine. Results so far indicate high calibration accuracy for chemical components (SECV 0.3 to 2.6%) and very promising statistics for in vivo DMD (SECV 1.8, $R^2$ 0.93, SD 7.0, range 61.9 to 92.3, n=60). There appears to be some potential for NIR to estimate some in vitro properties, depending upon the accuracy of reference methods and appropriate sample populations. Current work is in progress to extend the range of grains with in vivo DMD values (a very laborious and expensive process) and to increase the robustness of the various NIR calibrations, with the aim of implementing uniform testing procedures for nutritional value of grains throughout Australia.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.3
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• pp.320-326
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• 2017

This study is based on the hot air welding application method of EVA sheet to test the tensile strength performance changes due to the hot air welding speed, temperature and chemical attack. For the parameters of the study, the hot air welding method that directly heats the overlap between the sheets and the adhesion surface was controlled, and the maximum temperature for application was set to $20^{\circ}C$, $0^{\circ}C$, $-5^{\circ}C$, $-10^{\circ}C$. According to the results of the testing, the tensile strength of the overlap area was the highest between the temperatures of 20 at 5~6m/min and between the low temperatures at 3~4m/min of hot air welding speed.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.4
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• pp.377-383
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• 1997

Studies were conducted on the nature of allelopathic effect of the substances in the waste of ginkgo leaves from pharmaceutic factory. In the first step, to find out whether there was any allelophatic effect, young seedlings of radish and rice were grown in the water (crude) extract of ginkgo leaf waste and in different liquid/lquid partitioned fractions of EtOAc at pH 9, EtOAc at pH 3, and BuOH. As second step, attempts were made to isolate and identify the allelophatic substance in different liquid/liquid partitioned fractions using GC/MS and NMR techniques. The water (crude) extract of ginkgo leaf waste retarded the growth of radish seedlings under 10% concentration. In case of rice seedlings, the water extract of ginkgo leaf extract showed adverse effect on the growth when combined with $3.3{\times}10^{-6}M$ gibberellin A3. All of the liquid/liquid fractions of crude extract showed strong retardation of seedling growth of radish and rice at the concentration of 1%. Allelophatic substance was isolated from the crude extract using liquid/liquid partition, column chromatography and HPLC techniques. The analytical results of isolated componet using GC/MS and NMR proved that the allelophatic substance in the ginkgo leaf wastes is catechol; one of phenol compounds. Based on the experiences current study, a practical method for the testing of allelophatic effect of crude extract of some materials was proposed. In this method, rice seeds were allowed to sprout until the length of coleoptile to reach 0.5 mm. Such seedlings were submerged in the solution containing supposedly allelophatic substance and the length of shoot and root was measured 3 days after treatment.

• Journal of the Korea Organic Resources Recycling Association
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• v.28 no.3
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• pp.37-44
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• 2020

The Project supporting organic fertilizer started in 1999 as a national policy. In farmhouse, over application of mixed organic compound fertilizer(OC) caused salt accumulation in plastic film house soil. To replace inorganic fertilizer with OC fertilizer, this study was investigated the effect of OC application on yield and soil chemical properties for lettuce cultivation in plastic film house. The OC fertilizer was applied at 50(OC50+N50), 100(OC100), and 150(OC150) % level of the basal amount of nitrogen fertilizer in soil testing recommendation. And these were compared to NPK(nitrogen, phosphat, and potash fertilizer) and PK treatment. The yield of lettuce in OC100 was similar to that of NPK treatment. In OC 50, 100 and 150 treatments, pH had a tendency to increase than that of NPK treatment. Nitrate nitrogen(NO₃-N) and electrical conductivity(EC) were similar to NPK treatment. These showed that nutrients from OC fertilizer were less likely to accumulate in soil than NPK. Also, use efficiency of nitrogen in OC100 treatment were similar to NPK treatment. These results suggest that OC application as the basal dressing at the 100% level could be best to prevent a nutrient accumulation of soil and to increase the yield and commercial quality for lettuce.

• Environmental Analysis Health and Toxicology
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• v.28
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• pp.7.1-7.9
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• 2013

Objectives We investigated the particle mass size distribution and chemical properties of air pollution particulate matter (PM) in the urban area and its capacity to induce cytotoxicity in human bronchial epithelial (BEAS-2B) cells. Methods To characterize the mass size distributions and chemical concentrations associated with urban PM, PM samples were collected by a 10-stage Micro-Orifice Uniform Deposit Impactor close to nearby traffic in an urban area from December 2007 to December 2009. PM samples for in vitro cytotoxicity testing were collected by a mini-volume air sampler with $PM_{10}$ and $PM_{2.5}$ inlets. Results The PM size distributions were bi-modal, peaking at 0.18 to 0.32 and 1.8 to $3.2{\mu}m$. The mass concentrations of the metals in fine particles (0.1 to $1.8{\mu}m$) accounted for 45.6 to 80.4% of the mass concentrations of metals in $PM_{10}$. The mass proportions of fine particles of the pollutants related to traffic emission, lead (80.4%), cadmium (69.0%), and chromium (63.8%) were higher than those of other metals. Iron was the dominant transition metal in the particles, accounting for 64.3% of the $PM_{10}$ mass in all the samples. We observed PM concentration-dependent cytotoxic effects on BEAS-2B cells. Conclusions We found that exposure to $PM_{2.5}$ and $PM_{10}$ from a nearby traffic area induced significant increases in protein expression of inflammatory cytokines (IL-6 and IL-8). The cell death rate and release of cytokines in response to the $PM_{2.5}$ treatment were higher than those with $PM_{10}$. The combined results support the hypothesis that ultrafine particles from vehicular sources can induce inflammatory responses related to environmental respiratory injury.