• The Plant Pathology Journal
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• 제38권3호
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• pp.182-193
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• 2022

Turfgrass, the most widely grown ornamental crop, is severely affected by fungal pathogens including Sclerotinia homoeocarpa, Rhizoctonia solani, and Magnaporthe poae. At present, turfgrass fungal disease management predominantly relies on synthetic fungicide treatments. However, the extensive application of fungicides to the soil increases residual detection frequency, raising concerns for the environment and human health. The bacterial volatile compound, 2,3-butanediol (BDO), was found to induce plant resistance. In this study, we evaluated the disease control efficacy of a combination of stereoisomers of 2,3-BDO and commercial fungicides against turfgrass fungal diseases in both growth room and fields. In the growth room experiment, the combination of 0.9% 2R,3R-BDO (levo) soluble liquid (SL) formulation and 9% 2R,3S-BDO (meso) SL with half concentration of fungicides significantly increased the disease control efficacy against dollar spot and summer patch disease when compared to the half concentration of fungicide alone. In field experiments, the disease control efficiency of levo 0.9% and meso 9% SL, in combination with a fungicide, was confirmed against dollar spot and large patch disease. Additionally, the induction of defense-related genes involved in the salicylic acid and jasmonic acid/ethylene signaling pathways and reactive oxygen species detoxification-related genes under Clarireedia sp. infection was confirmed with levo 0.9% and meso 9% SL treatment in creeping bentgrass. Our findings suggest that 2,3-BDO isomer formulations can be combined with chemical fungicides as a new integrated tool to control Clarireedia sp. infection in turfgrass, thereby reducing the use of chemical fungicides.

• 한국응급구조학회지
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• 제9권1호
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• pp.121-131
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• 2005

This study examined the attitude about Basic Life Support of college students, college students' perception of the efficacy and concerns regarding performing of Basic Life Support via a written survey. This study was conducted among the fresh students of college. The survey was done from March 1 to April 1, 2005. Total subjects in this study were 234. The collected data were analyzed, by SPSS. The summary of the research is as follows: The subjects who had previously heard about Basic Life Support were 94.3%. 2. The subjects who had previously learned about Basic Life Support were 11.9%. 3. The attitude of subjects to Basic Life Support education was positive. Of the respondents, 95.7% wanted to learn Basic Life Support and 56.8% would be williling to provide Basic Life Support to collapsed person. If known the method of Basic Life Support than 83.3% of subjects would be willing to provide Basic Life Support to collapsed person. 4. Over than half(56.8%) indicated, that they would attempt to provide Basic Life Support if a student collapsed. 5. Concerns regarding performing Basic Life Support on students was 'doing it correctly'. 6. The subjects who had previously heard about AED were 65.0%. This study suggests that college students high perception of the effectiveness of the Basic Life Support and that they would be willing to provide Basic Life Support in a medical emergency.

• Asian-Australasian Journal of Animal Sciences
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• 제21권5호
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• pp.754-768
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• 2008

The past decades have seen enormous advances in our understanding of how GH acts. GH is a pituitary-derived polypeptide hormone that has diverse physiological effects including the regulation of bone growth, carbohydrate and lipid metabolism. The effects of GH are mediated directly and indirectly through IGF-I. In addition, GH stimulates the hepatic production of ALS. In postnatal life, IGF-I and -II circulate as 150 kDa ternary complexes consisting of one molecule each of IGFBP-3 or IGFBP-5, IGF-I or IGF-II and ALS. It is now known that ALS increases significantly the half-lives of the IGFs, IGFBP-3 and -5, and therefore is responsible for maintaining a circulating reservoir for each of these proteins.

• 유공압시스템학회논문집
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• 제1권1호
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• pp.10-16
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• 2004

The failures such as leakage and burst stemmed from the repetitive motions of bending and stretching of the assembly of hydraulic hose in construction machines, agriculture machines, vehicles, and industrial heavy machines can induce big troubles. Therefore, the hydraulic hose itself eventually requires an estimation of life to operate the hydraulic system safely. In this research, we have qualitatively selected the efficient test items by the analysis of the life and potential failures of hydraulic hose. We have used more than seven of hydraulic hoses simultaneously for the research. We have applied impulse pressure and half omega flexing motions to the accelerated life testing Test results have been expressed by employing weibull plot.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.129-130
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• 2006

This paper presents a study on the effect of feedrate changes on the fatigue life of Al 7075-T6 specimens before and after shotpeening. For this purpose. five groups of specimens, each of which consists of eight specimens, were first machined at five different feedrates (0.05, 0.10, 0.15, 0.20 0.25 mm/rev). Half of eight specimens in each group were then peened and the others remained un-peened Finally, the fatigue life of each specimen was measured by using 4-point rotatry bending machine. Comparison of fatigue life among ten sets of specimens is presented.

• 농약과학회지
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• 제19권4호
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• pp.361-369
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• 2015

본 연구는 엇갈이배추 중 bistrifluron과 fluopicolide의 잔류특성을 조사하여 약제별 잔류량 감소추이와 생물학적 반감기를 바탕으로 생산단계 잔류허용기준(pre-harvest residue limit, PHRL) 설정을 위한 기초자료로 활용하고자 수행되었다. 온실 재배 중인 엇갈이배추에 안전사용기준 농도로 희석한 bistrifluron과 fluopicolide를 다른 두 지역의 포장에 각각 살포 후 0 (2시간), 1, 2, 4, 6, 8, 10일에 시료를 채취하여 분석하였다. 엇갈이배추 중 두 성분의 잔류농약은 acetonitrile을 이용하여 추출하고 Florisil SPE cartridge로 정제한 후 HPLC/DAD를 이용하여 분석하였다. 두 시험농약의 정량한계는 $0.03mg\;kg^{-1}$이었고, 시험분석법의 회수율은 0.1 및 $0.5mg\;kg^{-1}$ 두 수준에서 87.2%~110.6%이었으며 상대표준편차는 모두 5% 미만이었다. 두 지역의 시험포장에서 엇갈이배추 중 각 시험농약의 생물학적 반감기는 bistrifluron의 경우 3.9일과 4.2일이었으며, fluopicolide의 경우 4.9일과 4.2일로 나타났다. 잔류회귀감소식을 이용하여 엇갈이배추 중 bistrifluron과 fluopicolide의 생산단계 잔류허용기준은 수확 10일 전 $3.83mg\;kg^{-1}$과 $3.23mg\;kg^{-1}$으로 제안하였다.

• Applied Biological Chemistry
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• 제47권1호
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• pp.113-119
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• 2004

시설재배 고추중 tiazole계 살균제 bitertanol과 tebuconazole에 대하여 안전사용기준의 추천량과 배량을 포장에 살포 후 잔류농약의 감소양상을 조사하였다. 고추중 bitertanol의 반감기는 $5.2{\sim}6.1$일 이었고, tebuconazole은 $4.6{\sim}5.2$일로 나타났다. 고추잎에서의 반감기는 bitertanol은 $19.1{\sim}22.5$일 이었고, tebuconazole은 $16.7{\sim}20.8$일로 나타나 고추에 비해 반감일수가 $3{\sim}5$배 증가하였다. 고추잎에서 약제살포 24일 경과후 bitertanol과 tebuconazole의 잔류량은 10.1 mg/kg, 17.5 mg/kg으로 나타났는데, 이는 고추잎에 대한 Maximum Residue Limit(MRL) 3.0 mg/kg, 5.0 mg/kg을 크게 넘는 수치로 조사되었다. 시설재배 고추와 고추잎에서의 경시변화는 1차 회귀방정식에 부합하였으며, 고추잎에서의 엽면잔류량(Dislodgeable Foliar Residues, DFRs)은 24일 경과후 각각 36%, 48%가 소실되는 것으로 나타났다. 세척방법에 의한 잔류농약의 감소량을 조사한 결과 세제 사용시의 평균제거율을 bitertanol은 72.4%, tebuconazole은 72.2%로 나타났고, 일반 수돗물 사용시에는 bitertanol 60.3%, tebuconazole 61.5%로 나타났다.

• 한국비블리아학회지
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• 제2권1호
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• pp.266-295
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• 1974

The purpose of this study is to make a contribution to the effective management of medical literature in Korean libraries and specifically to help to select medical books and periodicals by determining the value and life of medical literature by means of citation counting and analysis. This report will present methods of calculation and data collection to measure the importance, half life of medical literature and the authority of author for Korean medical libraries. The writer conducted comparative studies based on data covering a two-year period, 1970-1971, using about 16,899 citations in 1,032 articles of the above journals. The references and citations are counted and analyzed by the number of authors, periodicals. books and publication dates. By the following ratio. calculated by the citation counting and analysis, we can decide the rates of medical periodicals to books, foreign literature to domestic literature and literature of the most numerously cited. authors, for the selecting method of Korean Medical libraries. (1) It is disclosed that 61 main authors are cited 9 times. Most of them are Western authors, they are cited 14,374 times which represents 88.6 % of the total citations. (2) The cited medical literature is classified as follows: The ratio of cited medical periodicals to the cited medical books is 82.0%. (The books at a rate of 18.0%.) Therefore, the wnter concentrated the efforts on the analysis of periodicals. (3) Classification of the periodicals by countries indicates that about 11.2% of total citations are made from Korean medical literature. The medical activities in Korea are dependent on the advanced foreign countries at ratio of 88.8%. Of the foreign medical periodicals cited, Japanese literature represents only 4.5% while literature of European countries and America constitutes 84.3%. (4) If medical journals are arranged in order of decreasing productivity of articles on a given subject, they may be revealed that it is necessary to have 98 titles of key journals to cover 60% of information in the field of medical science and 60 titles for an average of 50%. (5) For the purpose of measuring the life of medical literature in Korea, the writer has calculated the half lives of periodicals and books as follows: Kinds of Literature 1. Periodicals 2. Books 3. Whole literature Half-lives 7.75 years 4.11 years 6.37 years (6) The half lives of domestic and Japanese literature in the medical science are comparatively short.

• 한국환경농학회지
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• 제11권1호
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• pp.1-8
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• 1992

농약분해에 관여하는 monooxygenase와 esterase의 활성을 저해하는 것으로 알려진 PBO와 TPP를 첨가하여 제조한 신(新)다이아지논입제에 대하여 벼멸구에 대한 살충률을 조사하였고, 아울러 신(新)다이아지논 입제와 두효소를 저해하는 작용기작을 가지고 있는 tricyclazole, carbofuran 그리고 EPN을 혼합하여 제조한 혼합다이아지논입제에 대하여 담수토양중의 잔류경향을 조사하였다. 1. 살균토양과 비살균토양에서 신(新)다이아지논 입제(0.1% 첨가)의 반감기는 4.53일과 2.33일 이었고, 시판품에 비하여 각각 0.74일과 0.45일 주성분의 분해가 지연되었다. 2. 신(新)다이아지논입제(0.1% 첨가)의 벼멸구에 대한 살충률은 추천량에서는 12%, 추천 1/2량에서는 $30{\sim}60%$가 증가되었다. 3. 신(新)다이아지논 입제 (1%)중 PBO 첨가는 토양중 반감기가 0.44일 그리고 PBO-TPP첨가로 0.65일 지연되었다. 4. 혼합다이아지논 입제는 시판품에 비하여 tricyclazole, carbofuran 그리고 EPN첨가로 반감기가 2.61일, 1.04일 그리고 0.43일 지연되었으며, EPN+carbofuran을 첨가하여 제조한 혼합다이아지논 입제는 2.7일 연장되었다.

• Advances in environmental research
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• 제2권1호
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• pp.9-17
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• 2013

Urine is a widely used matrix in biomonitoring studies on the assessment of human exposure to environmental chemicals such as phthalate esters and bisphenol A (BPA). In addition to the need to apply valid analytical techniques, assurance of specimen integrity during collection and storage is an important prerequisite for the presentation of accurate and precise analytical data. One of the common issues encountered in the analysis of non-persistent contaminants is whether shipping and storage temperature and time since collection have an effect on sample integrity. In this study, we investigated the stability of phthalate metabolites and BPA in spiked and unspiked urine samples stored at room temperature ($20^{\circ}C$) or at $-80^{\circ}C$ for up to 8 weeks. Concentrations of phthalate metabolites declined, on average, by 3% to 15%, depending on the compounds, and BPA declined by ~30% after 4 weeks of storage of spiked urine samples at $20^{\circ}C$. In a test of 30 unspiked urine samples stored at $20^{\circ}C$ and at $-80^{\circ}C$ for 8 weeks, the concentrations of phthalate metabolites and BPA decreased by up to 15% to 44%, depending on the compound and on the samples. It was found that the small reduction in phthalate concentrations observed in urine, varied depending on the samples. In a few urine samples, concentrations of phthalate metabolites and BPA did not decline even after storage at $20^{\circ}C$ for 8 weeks. We found a significant relationship between concentrations of target analytes in urine stored at $20^{\circ}C$ and at $-80^{\circ}C$ for 8 weeks. We estimated the half-lives of phthalate metabolites and BPA in urine stored at $20^{\circ}C$. The estimated half-life of monoethyl phthalate (mEP) and mono (2-ethyl-5-carboxyphentyl) phthalate (mECPP) in urine stored at $20^{\circ}C$ was over two years, of mono (2-ethyl-5-oxohexyl) phthalate (mEOHP) and monobenzyl phthalate (mBzP) was approximately one year, and of other phthalate metabolites was approximately 6 months. The estimated half-life of BPA in urine stored at $20^{\circ}C$ was approximately 3 months, which is much longer than that reported for aquatic ecosystems.