• The Korean Journal of Pesticide Science
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• v.19 no.3
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• pp.230-240
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• 2015

An IOM sampler equipped with glass fiber filter has been recently utilized instead of solid adsorbent, which was used to measure the inhalation exposure of agricultural operator to pesticides. The aim of this study is to validate the efficacy of an IOM sampler by measuring the trapping efficiency and breakthrough using kresoxim-methyl water-dispersible granule and fenthion emulsifiable concentrate. On LC-MS/ MS, minimum detection level was 12.5 pg and method limit of detection was 5.0 ng/mL. Good linearity ($R^2$ > 0.999) for matrix matched standards was obtained. Recoveries of pesticides from glass fiber filter were 102-109% (kresoxim-methyl) and 97-104% (fenthion) while those from XAD-2 resin were 94-98% (kresoxim methyl) and 93-100% (fenthion). Trapping efficiency test was performed with personal air pumps and IOM sampler (glass fiber filter) connected with solid adsorbent (XAD-2 resin) with two types of formulation (solid and liquid) which were diluted by standard rate and sprayed to IOM sampler. Those pesticides were trapped only in glass fiber filter without any breakthrough to solid adsorbent. After spiking of pesticides to glass fiber filter, breakthrough test was carried out with IOM sampler (glass fiber filter) which was connected with solid adsorbent. As a results, 87-101% of kresoxim-methyl and 96-105% of fenthion remained in spiked glass fiber filter, however, no pesticides were detected in second glass fiber filter and solid adsorbent. In conclusion, IOM sampler which equipped with glass fiber filter can be applied widely for pesticide inhalation exposure study since it has good trapping efficiency and adsorption capacity, regardless of the solid or liquid formulation.

• Horticultural Science & Technology
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• v.30 no.1
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• pp.27-33
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• 2012

This study aimed to investigate the responses of plant growth and blossom-end rot (BER) incidence to calcium (Ca) and its three kinds of antagonistic cations (K, Mg, and $NH_4$-N) with various ratios in nutrient solution for sweet paper (Capsicum annuum L. 'RZ208'). Both Ca to each cation and Ca to a series of cation combinations, such as potassium (K), ammonium nitrate ($NH_4$), or magnesium (Mg) were more influential to the fruit growth and quality than plant growth. Especially, the BER incidence was significantly influenced by the ratio treatments. For examples, when Ca:(K + Mg) or Ca:(K + Mg + $NH_4$) ratio was 1:2 the highest incident rate of BER about 70.3 or 86.3% was observed, lowering the marketable yield to 19 or 13.7% of the total yield, respectively. The correlation coefficiencies (= r) to relationships between the BER and K as well as BER and $NH_4$ were 0.82 (P < 0.05) and 0.65 (P < 0.05), respectively. Combination only with the Mg element was not correlated with the BER incidence. However, when both of the K and Mg concentrations were 0.65 (P < 0.05). The highest correlation coefficiency, 0.92 (P < 0.05), was found to a relationship between the BER and the tree elemental combination.

• Journal of Mushroom
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• v.10 no.2
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• pp.83-92
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• 2012

To provide a basis for the variation of fruit bodies of winter mushroom (Flammulina velutipes), the organic acid composition of its fruit bodies was investigated with several varieties of winter mushroom indifferent temperature and storage period. In the fruit bodies of winter mushroom, a total of 10 organic acids including acetic acid, butyric acid, citric acid, fumaric acid, DL-isocitric acid, L(+)lactic acid, D-malic acid, propionic acid, succinic acid, and D-tartaric acid were detected. In the most of the winter mushroom, acetic acid was the main organic acid component and fumaric acid was the least included component. Acetic acid, which is a mono-carboxyl group of organic acid, is contained in different levels according to different varieties and different storage temperature. Butyric acid is extremely variable in its quantity, depending on variety and different storage temperature. In contrast, fumaric acid, which is a dicarboxyl group of organic acid, decreased in its quantity during storage with 1.5 mg/g. Especially, ASI 4149, 4166 varieties tend to differ in their quantity. Besides, malic acid is extremely variable in its quantity according to variety and storage temperature. Citric acid, a tri-carboxyl group of organic acid, increased in its quantity according to storage period, which enables us to efficiently manage storage period. Isocitric acid is also extremely variable in its quantity according to variety, storage temperature and storage period.

• Journal of Korean Society of Forest Science
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• v.90 no.4
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• pp.413-419
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• 2001

This study investigated pH values and EC changes of rainfall and stemflow were investigated for 5 tree species such as Pinus koraiensis, P. densiflora, Larix leptolepis, Quercus variabilis and Q. mongolica in the Experiment Forests, College of Forest Science, Kangwon National University. The results were as follows; 1. Mean month pH values of stemflow were much lower than those of rainfall. Among tree species, pH values of the coniferous such as P. densiflora, P. koraiensis and L. leptolepis were lower those of the deciduous such as Q. mongolica and Q. variabilis. Mean month pH values of stemflow ranged from 3.23 to 5.03 (average : 4.23) for P. koraiensis, 3.57 to 5.16 (average : 4.36) for P. densiflora, 3.41 to 6.69 (average : 4.45) for L. leptolepis, 3.86 to 6.11 (average : 4.70) for Q. variabilis and 4.39 to 6.13 (average : 5.18) for Q. mongolica. 2. Mean month EC of the coniferous species was 1.5 to 2 times higher than that of the deciduous species. Mean month EC of stemflow for P. koraiensis, P. densiflora, L. leptolepis, Q. variabilis and Q. mongolica was ranged from 29.0 to $946.5{\mu}S/cm$(average : $258.5{\mu}S/cm$), 18.6 to $907.5{\mu}S/cm$(average : $220.3{\mu}S/cm$), 27.0 to $918.0{\mu}S/cm$(average : $216.2{\mu}S/cm$), 16.5 to $301.6{\mu}S/cm$(average : $125.4{\mu}S/cm$) and $25.2{\sim}225.7{\mu}S/cm$(average : $101.5{\mu}S/cm$), respectively. 3. Average pH values and EC were highly variable according to season. Average pH values appeared lower in spring than those in summer and autumn, but EC appeared higher in spring than those lower in summer and autumn. 4. According to precipitation, there was little difference in and pH values of stemflow the coniferous and the deciduous showed low pH valuess in the case of less than 50mm precipitation. However, EC of stemflow showed a difference depending on the precipitation, and EC of the coniferous and the deciduous was high more than $100{\mu}S/cm$ at the precipitation of less than 50mm.

• Journal of dental hygiene science
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• v.8 no.2
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• pp.73-80
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• 2008

The purpose of this study was to examine the health promotion behavior of dental hygiene students in boosting a university student health. The subjects in this study were 687 dental hygiene students in four different colleges in Gyeonggi province. A survey was conducted in September and October 2007, and the collected data were analyzed with SPSS 12.0 program. The findings of the study were as follows: 1. The he freshmen scored lowest in oral health care behavior($3.11{\pm}.57$), and the gap between them and the others was statistically significant (p < .001). 2. In regard to health promotion behavior, the students who found themselves not to be in good shape scored lower in terms of nutritional care($3.63{\pm}.63$), social support($2.43{\pm}.60$), responsibility for their own health($2.40{\pm}.68$) and esteem for their own lives($2.33{\pm}.51$). There were statistically significant differences between them and the others(p < .001, p < 0.01). 3. As to the relationship of the academic background of parents to health promotion behavior, the students whose fathers stopped at middle school($3.62{\pm}.52$) lagged behind most in terms of nutritional (p < .001), and those whose mothers stopped at middle school($2.52{\pm}.52$) were given the smallest social support. The gap between these groups and the others were statistically significant(p < .05). 4. The self-boarding students($3.66{\pm}.57$) fall behind most in the aspect of nutritional care, and there was a statistically significant gap between them and the others(p < .001). 5. The students whose monthly mean household income was one million won or less($2.42{\pm}.62$) valued their own lives least, and the gap between them and the others was statistically significant(p < .05). 6. As for correlation among the variables, stronger social support led to better reverence for life, and better esteem for life was concurrent with better stress management. There was a statistically significant relationship between those variables(p < .01).

• Korean Journal of Environment and Ecology
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• v.28 no.5
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• pp.531-541
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• 2014

This research investigated the reproduction cycle, litter size, and the effects of factors of red-tongue viper snake inhabiting in Jeju Island, to delve into their life strategy. Field survey was conducted in Jeju Island from May 2006 to November 2008. Reproduction cycle was analyzed through measurements of testis and follicle sizes in laboratory from March 2009 to December 2010. According to the research results, the sizes of red-tongue viper snake's testis and follicle clearly changed seasonally. The number of eggs within the oviduct were greater on the right side ($2.6{\pm}1.0$ eggs, n=16) than on the left side ($1.8{\pm}0.5$ eggs, n=16) (t=-2,721, p<0.05). Average (${\pm}SD$) of survival litter size (SLS) was $4.4{\pm}1.7$ (1~9, range), while total litter size (TLS) was $4.7{\pm}1.5$ (3~9, range), which were not statistically significant. However, their litter sizes were similar to the number of eggs within the oviduct (t=0.039, P>0.05). Relative litter mass (RCM) was $0.42{\pm}0.13$ (0.18~0.79, n=33), and tended to increase, as maternal condition of pre-parturition (MCPPI) was getting better. The sexual ratio of delivered litters showed no significant difference between male and female red-tongue viper snakes (♂:♀ = 1.15:1, n=73 ; ${\chi}^2$=0.342, P>0.5). Average neonate mass showed a weak correlation with maternal mass of pre-parturition (MMPP1) (r=0.387, P<0.05, n=33). Average neonate Snout-vent length (SVL) also demonstrated a weak correlations with maternal SVL (r=0.399, P<0.05, n=33) and MMPP1 (r=0.344, P<0.05, n=33). Average neonate mass and maternal SVL approached significant probability (r=0.323, P=0.067, n=33). This indicates that mother snakes can bear bigger litter due to its larger size. In some cases, litter's weight decreases as mother snakes are bearing more litter; however, the red-tongued viper snake did not show such exchange relationship. From this, it can be conjectured that a red-tongued viper snake has peculiarity of its own species. The research results are predicted to be used as the basis to find a life history of red-tongued viper snake.

• Journal of Distribution Science
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• v.7 no.3
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• pp.71-100
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• 2009

The main purpose of this study is to define relevant factors that influence successful start-ups and management innovations of traditional markets from the point of market structures and relations. To do this, we devide an entrepreneurship of merchant into two factors, risk taking and managerial experience and choose product planning and its implementation to see merchandising of traditional markets. In this study we identify that several factors we chose are contributing to generating management performances through market promotional parameters. Also we confirm that image factors of traditional markets is consist of awareness and value of markets, and that these factors shows some sequential and continual patterns in the course of generating performances. In additions, it is identified that four independent factors have positive effects to star-up success; risk taking 0.29(t 2.61), managerial experience 0.04(t 1.79), merchandising implementation 0.374(t 2.61), market value 0.47(t 5.25), market awareness 0.22(t 2.30). This study can help merchants of traditional markets to make and change their market strategies, restructure their businesses and survive in the field. This also provide some ideas and guidances to relevant government agencies in formulating traditional market policies.

• The Journal of Korean Society for Radiation Therapy
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• v.29 no.2
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• pp.109-117
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• 2017

Objectives: The purpose of this study was to evaluate the change of body shape and the patient alignment state during image-guided volumetric modulated arc therapy in head and neck cancer patients, Materials and Methods: We performed a image-guided volumetric modulated arc therapy plan for 89 patients with head and neck cancer who underwent curative radiotherapy. Ten of them were evaluated for set up error. The landmarks of the ramus, chin, posterior neck, and clavicle were specified using ARIA software (Offline review), and the positional difference was analyzed. Results: The re-CT simulation therapy was performed in 60 men with $17{\pm}4$ cycles of treatment. The weight loss rate was $-6.47{\pm}3.5%$. 29 women performed re-CT simulation at $17{\pm}5$ cycles As a result, weight loss rate was $-5.73{\pm}2.7%$. The distance from skin to C1, C3, and C5 was measured, and both clavicle levels were observed to measure the skin shrinkage changes. The skin shrinkage standard deviations were C1 (${\pm}0.44cm$), C3 (${\pm}0.83cm$), and C5 (${\pm}1.35cm$), which is about 1 mm shrinkage per 0.5 kg reduction. Skin shrinkage according to the number of treatments was 1 ~ 4 fractions (no change), 5 ~ 13 fractions (-2 mm), 14 ~ 22 fractions (-4 mm) and 23 ~ 30 fractions (-6 mm). Conclusion: When the body shape changes about 5 mm, the central dose starts to differ about 3 % or more. Therefore, the CT simulation treatment for the adaptive therapy should be additionally performed. In addition, it is necessary to actively study the CT simulation therapy method and set up method of the lower neck and to examine the use of a new immobilization device.

• Korean Journal of Environment and Ecology
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• v.30 no.6
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• pp.1009-1021
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• 2016

The community structure and abundance of epilithic biofilm were bimonthly examined to know spatial and temporal patterns of biofilm biomass and taxonimical composition at the two study sites, Gosapo and Gyeokpo with different degrees of wave exposure levels from November 2010 to September 2011. Biomass was estimated by using chlorophyll a contents (Chl a), normalized difference vegetation index (NDVI), and vegetation index (VI). Cyanobacteria such as Aphanotece spp. predominated in the proportion of 57.53% at Gosapo and of 61.12% at Gyeokpo and they are abundant in mid shore and in summer at both study sites. The diatoms Navicula spp., Achnanthes spp. and Licmophora spp. were common species and they showed an increasing trend from high to low shore. NDVI, VI, and chl a contents were the greatest at mid shore for Gosapo (0.44, 3.05, $24.56{\mu}g/cm^2$) and at low shore for Gyeokpo (0.41, 2.73, $17.98{\mu}g/cm^2$). NDVI, VI, and chl a content were all maximal in January and minimal in March at the both sites. Average NDVI, VI, and chlorophyll a contents of biofilms were greater at Gosapo (0.43, 2.89, $22.84{\mu}g/cm^2$) than Gyeokpo (0.38, 2.48, $15.48{\mu}g/cm^2$).Of three shore levels(high, mid, and low) Chl a contents were positively correlated with NDVI and VI at the two study sites indicating that non-destructive NDVI and VI values can be used in stead of destructive Chl a extraction method. In conclusion, epilithic biofilm was more abundant seasonally in winter, vertically in mid and low intertidal zone, and horizontally at wave exposed shore than in summer, at high and sheltered shore in Korea.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.1
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• pp.47-56
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• 1999

$^{15}N$-Isotope concentrations of groundwater from l4 wells with different land-use types in Kyonggi Province were measured to investigate the nitrate contamination sources. Water samples were collected monthly from January to December 1997 and analyzed for pH. PC, anions (fluoride, chloride, nitrate, sulfate, inorganic phosphate, and bicarbonate), and canons (calcium, magnesium, potassium, and sodium). For the analysis of the $^{15}N/^{14}N$ ratio as ${\delta}^{15}N$, $N_2$ samples were prepared through Kjeldahl-Rittenberg method and were analyzed using an isotope ratio mass spectrometer (VG Optima IRMS). Reproducibility of the method and precision of the IRMS were below 1.0‰ and 0.1‰, respectively. The ionic composition of each groundwater sample was only slightly different according to the land-use type. The nitrate concentrations of groundwater in cropland or livestock farming areas were higher than those in the residential area. The percentages of nitrate to total anions of groundwater samples from the livestock farming area were higher than those of other areas. The ${\delta}^{15}N$ values of ammonium sulfate, urea, groundwater sample in the non-contaminated area, and water from the animal manure septic tank were -2.7, 1.4, 5.5, and 27.2‰, respectively. Based on the ${\delta}^{15}N$ values, the sources of nitrate could be classified as originated from chemical fertilizers with ${\delta}^{15}N$ values below 5% and as from animal manure or municipal waste with ${\delta}^{15}N$ values over 10‰. In most cases, contamination sources investigated from ${\delta}^{15}N$ values of groundwater samples were correlated with the specific sources according to the land-use types. However, some ${\delta}^{15}N$ values did not matched the apparent land-use types, and there were seasonal variations of ${\delta}^{15}N$ values within the same well. These results suggest that the groundwater quality was affected by two or more contamination sources and the contribution of each source to the groundwater quality varied depending on the sampling season.