• 제목/요약/키워드: RapidArc

검색결과 142건 처리시간 0.037초

Mechanisms for Hfq-Independent Activation of rpoS by DsrA, a Small RNA, in Escherichia coli

  • Kim, Wonkyong;Choi, Jee Soo;Kim, Daun;Shin, Doohang;Suk, Shinae;Lee, Younghoon
    • Molecules and Cells
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    • 제42권5호
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    • pp.426-439
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    • 2019
  • Many small RNAs (sRNAs) regulate gene expression by base pairing to their target messenger RNAs (mRNAs) with the help of Hfq in Escherichia coli. The sRNA DsrA activates translation of the rpoS mRNA in an Hfq-dependent manner, but this activation ability was found to partially bypass Hfq when DsrA is overproduced. The precise mechanism by which DsrA bypasses Hfq is unknown. In this study, we constructed strains lacking all three rpoS-activating sRNAs (i.e., ArcZ, DsrA, and RprA) in $hfq^+$ and $Hfq^-$ backgrounds, and then artificially regulated the cellular DsrA concentration in these strains by controlling its ectopic expression. We then examined how the expression level of rpoS was altered by a change in the concentration of DsrA. We found that the translation and stability of the rpoS mRNA are both enhanced by physiological concentrations of DsrA regardless of Hfq, but that depletion of Hfq causes a rapid degradation of DsrA and thereby decreases rpoS mRNA stability. These results suggest that the observed Hfq dependency of DsrA-mediated rpoS activation mainly results from the destabilization of DsrA in the absence of Hfq, and that DsrA itself contributes to the translational activation and stability of the rpoS mRNA in an Hfq-independent manner.

Dosimetric Analysis of Lung Stereotactic Body Radiotherapy Using Halcyon Linear Accelerator

  • Shinhaeng Cho;Ick Joon Cho;Yong Hyub Kim;Jea-Uk Jeong;Mee Sun Yoon;Taek-Keun Nam;Sung-Ja Ahn;Ju-Young Song
    • Progress in Medical Physics
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    • 제34권4호
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    • pp.48-54
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    • 2023
  • Purpose: In this study, the dosimetric characteristics of lung stereotactic body radiotherapy (SBRT) plans using the new Halcyon system were analyzed to assess its suitability. Methods: We compared the key dosimetric parameters calculated for the Halcyon SBRT plans with those of a conventional C-arm linear accelerator (LINAC) equipped with a high-definition multileaf collimator (HD-MLC)-Trilogy Tx. A total of 10 patients with non-small-cell lung cancer were selected, and all SBRT plans were generated using the RapidArc technique. Results: Trilogy Tx exhibited significant superiority over Halcyon in terms of target dose coverage (conformity index, homogeneity index, D0.1 cc, and D95%) and dose spillage (gradient). Trilogy Tx was more efficient than Halcyon in the lung SBRT beam delivery process in terms of the total number of monitor units, modulation factor, and beam-on time. However, it was feasible to achieve a dose distribution that met SBRT plan requirements using Halcyon, with no significant differences in satisfying organs at risk dose constraints between both plans. Conclusions: Results confirm that Halcyon is a viable alternative for performing lung SBRT in the absence of a LINAC equipped with HD-MLC. However, extra consideration should be taken in determining whether to use Halcyon when the planning target volume setting is enormous, as in the case of significant tumor motions.

A Bibliographic Study on the Types of Differential Diagnosis of Amnesia (건망(健忘)의 변증분형(辨證分型)에 대(對)한 연구(硏究))

  • Choi, Yong-Jun;Seong, Gang-Gyoung;Mun, Byoung-Sun
    • The Journal of Korean Medicine
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    • 제17권1호
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    • pp.374-406
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    • 1996
  • This study has been carried out to investigate the types of differential diagnosis of amnesia. The results are as follows; 1. Amnesia has various types of differential diagnosis(辨證分型) ; deficiency of both the heart and spleen(心脾兩虛型), deficiency of the heart(心虛型), deficiency of the kidney(腎虛型), breakdown of the coordination between the heart and the kidney(心腎不交型), mental confusion due to phlegm(痰迷心竅型), accumulation of stagnant blood(蓄血型), internal injury by seven emotion (七情所傷型). 2. The type of deficiency of both the heart and spleen(心脾兩虛型) occurs when the heart and spleen is injured by overthinking(思慮過度), The symptoms are heart palpitation(心悸), continuous palpitation(??), insomnia(少寐), hypochondric discomfort(心煩), dream disturbed sleep(多夢), being easy to be scared(易驚), dizziness(眩暈), these are caused by blood deficiency of the heart(心血不足), poor appetite(飮食不振), loss of appetite(納?), short breath(氣短), sense of turgid abdormen(腹部膨滿感), loose stool(泥狀便), these are caused by deficiency of the spleen(脾虛), lassitude and weakness (身倦乏力), lassitude of the extremities (四肢無力), dim complexion (面色少華), pale lips(舌質淡), thready and feeble(脈細弱無力), these are caused by deficiency of both qi and the blood(氣血虛損). The remedy is nourishing the heart-blood(養心血) and regulating the spleen(理脾土). I can prescribe the recipes such as Guibitang(歸脾湯), Gagambosimtang(加減補心湯), Seongbitang(醒脾湯), Insin-guisadan(引神歸舍丹), Insamyangyoungtang(人蔘養榮湯), Sojungjihwan(小定志丸), Yungjigo(寧志膏), Palmijungjihwan(八味定志丸), etc., 3. The type of deficiency of the heart(心虛型) occurs when the heart-blood is injured by the mental tiredness(神勞) and so blood cannot nourish the heart. The symptoms are amnesia(健忘), short breath(氣短), heart palpitation(心悸), perspire spontaneously(自汗), facial pallidness(顔面蒼白), pale lips (舌質淡白), feeble pulse and lassitude(脈虛無力), intermittent pulse(結代脈). The remedy is nourishing the hart and blood and allaying restlessness(補心益血安神). I can prescribe the recipes such as Chenwangbosimdan(天王補心丹), Jeongji-hwan(定志丸), Gaesimhwan(開心丸), Youngjigo(寧志膏), Chilseonghwan(七聖丸), Baegseogyoungtang(白石英湯), Oseohwan(烏犀丸), Yangsinhwan(養神丸), Guisindan(歸神丹), Bogsinsan(茯神散), Jinsamyohyangsan(辰砂妙香散), Cheongeumboksinsan(千金茯神散), Samjotang(蔘棗湯), jangwonhwan(壯元丸), Sa gunjatang(四君子湯) minus rhizoma atractylodis macrocephalae(白朮) plus rhizoma acori graminei(石菖蒲), radix polygalae(遠志), cinnabaris(朱砂), etc. 4. The type of deficiency of the kidney(腎虛型) occurs when the kidney-qi and kidney-essence is deficient(腎氣腎精不足) and so it cannot nourish the brain. The symptoms arc amnesia(健忘), ache at the waist and lassitude in the lower extremities(腰산腿軟), dizziness and tinnitus(頭暈耳嗚), emmission and premature ejaculation(遺精早泄), burning sensation of the five centres(五心煩熱), flushed tongue(舌紅), rapid and small palse(脈細數). The remedy is nourishing the kidney and strengthen the essence(補腎益精). I can prescribe the recipes such as Gagamgobonhwan(加減固本丸), Jeongjihwan(定志丸), Gongseongchlmjungdan(孔聖枕中丹), Yugmigihwanghwan(六味地黃丸) plus ra-dix polygalae(遠志), fructus schizandrae(五味子), Yugmigihwanghwan(六味地黃丸) plus radix polygalae(遠志), fructus schizandrae(五味子), rhizoma acori graminei(石菖蒲), semen zizyphi spinosae(酸棗仁), Palmihwan(八味丸) plus fructus schizandrae(五味子), semen zizyphi spinosae(酸棗仁). etc., 5. The type of breakdown of the coordination between the heart and the kidney (心腎不交型) occurs when the heart-fire(心火) and kidney-fluid(腎水) are imbalanced. The symptoms are amnesia(健忘), hypochondric discomfort(心煩), insomnia(失眠), dizziness and tinnitus(頭最耳嗚), feverish sensation m the palms and soles(手足心熱), emmision(遺精), ache at the waist and lassitude in the lower extremities(腰?腿軟), flushed tongue(舌紅), rapid pulse(脈數). The remedy is coordinating each other(交通心腎). I can prescribe the recipes such as Gangsimdan(降心丹), Jujaghwan(朱雀丸), Singyotang(神交湯), Simsinyang- gyotang(心腎兩交湯), Yugmihwan(六味丸) plus fructus schizandrae(五味子), radix polygalae(遠志), Yugmihwan(六味丸) plus fructus schizandrae(五味子), radix polygalae(遠志), rhizoma acari graminei(石菖蒲), semen zizyphi spinosae(酸棗仁), etc., 6. The type of mental confusion due to phlegm(痰迷心竅型) occurs when the depressed vital energy(氣鬱) create phlegm retention(痰飮) and phlegm stagnancy(痰濁) put the heart and sprit(心神) out of order. The symptoms arc amnesia(健忘), dizziness(頭暈), chest distress(胸悶), nausea(惡心), dull(神思欠敏), dull and slow facial expression(表情遲鈍), tongue with yellow and greasy fur(舌苔黃?), sliperry pulse(脈滑). The remedy is removing heat from the heart to restore consciousness and dispersing phlegm(淸心化痰開竅) I can prescribe the recipes such as Gamibogryeongtang(加味茯?湯), Goa-rujisiltang(瓜蔞枳實湯), Jusaansinhwan(朱砂安神丸), Dodamtang(導痰湯) plus radix saussurea(木香), Yijintang(二陳湯) plus succus phyllostachyos(竹瀝), rhizoma zingiberis(生薑) Ondamtang(溫膽湯) plus rhizoma acori graminei(石菖蒲), rhizoma curcumae aromaticae(鬱金), etc., 7. The type of accumulation of stagnant blood(蓄血型) occurs when the blood is accumulated in the lower part of body. The symptoms are amnesia(健忘), chest distress(胸悶), icteric skin(身黃), rinsing the mouth but don't wanting eat(漱水不欲燕), madness(發狂), black stool(屎黑), pain in the lower abdomen(小腹硬痛). The remedy is dispersing phlegm and absorb clots (化痰化瘀), I can prescribe the recipes such as Jeodangtang(抵當湯), Daejeodanghwan(代抵當丸), Hyeolbuchugeotang (血府逐瘀湯) plus rhizoma acori graminei (石菖蒲), rhizoma curcumae aromaticae(鬱金), Jusaansinhwan(朱砂安神丸) plus rhizoma curcumae aromaticae(鬱金), radix polygalae(遠志), semen persicae(桃仁), cortex moutan radicis(收丹皮), etc., 8. The type of internal injury by seven emotion(七情所傷型) occurs when the anger injures the will stored in the kidney(腎志). The symptoms are amnesia(健忘), heart palpitation(心悸). hot temper(易怒), being easy to be scared(善驚), panic(易恐). The remedy is relieving the depressed liver and regulating the circulation of qi(疏肝解鬱). I can prescribe the recipes such as Tongultang(通鬱湯), Sihosogantang(柴胡疏肝湯) plus rhizoma acari graminei(石菖蒲), rhizoma curcumae aromaticae(鬱金), etc.

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Site Selection of Wildlife Passage for Leopard Cat in Urban Area using Space Syntax (공간구문론을 이용한 도시 내 삵 이동통로 적지선정)

  • Park, Jong-Jun;Woo, Dong-Geol;Oh, Dae-Hyun;Park, Chong-Hwa
    • Journal of the Korean Institute of Landscape Architecture
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    • 제40권1호
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    • pp.92-99
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    • 2012
  • Many wildlife habitats have been destroyed and fragmented during the rapid industrialization and urbanization process in Korea. It is essential to connect these fragmented habitats to reduce road-kill of many types of endangered urban wildlife. The site selection for wildlife passages must take into account the behavior of the wildlife species for safe crossing utilizing many artificial barriers in urban areas. This study attempted to identify potential wildlife passage sites for the endangered and protected leopard cats of Gangseo Ecological Park in Seoul, Korea. A space syntax analysis, an analytical technique to objectively evaluate the spatial configurations related to passage selection, found that the integration value represents the accessibility and connectivity of spaces. In this paper, this means that the bigger the integration value, the more frequently the leopard cat passes through. The leopard cats were captured and radio-tracked for 72 hours once a month from March to June of 2009. The ArcGIS and Animal Movement of Hawth Tools were used to analyze the home range and movement paths, and Axwoman 4.0 was used to analyze space syntax. The daily average movement distance was $2.099{\pm}1.08km$. During the survey period, the leopard cats crossed over an urban expressway more than 20 times, running the risk of road-kill. The range of global integration values was 0.458~1.834, while that of the local integration was 0.210~6.061. Five sites that met across the leopard cats' movement routes and roads were selected to measure the local and global integrate values. Among these sites, the higher the integration value, the higher the road-kill possibility. Thus, two of five sites with high global and local integration values were suggested as potential wildlife passage sites for the leopard cats. Now, three tunnel passages are under construction at the suggested sites for which local integration value was highest (LI=4.369). Further studies are scheduled to verify these potential sites as suitable wildlife passages.

A Study of a Correlation Between Groundwater Level and Precipitation Using Statistical Time Series Analysis by Land Cover Types in Urban Areas (시계열 분석법을 이용한 도시지역 토지피복형태에 따른 지하수위와 강수량의 상관관계 분석)

  • Heo, Junyong;Kim, Taeyong;Park, Hyemin;Ha, Taejung;Kang, Hyungbin;Yang, Minjune
    • Korean Journal of Remote Sensing
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    • 제37권6_2호
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    • pp.1819-1827
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    • 2021
  • Land-use/cover change caused by rapid urbanization in South Korea is one of the concerns in flood risk management because groundwater recharge by precipitation hardly occurs due to an increase in impermeable surfaces in urban areas. This study investigated the hydrologic effects of land-use/cover on groundwater recharge in the Yeonje-gu district of Busan, South Korea. A statistical time series analysis was conducted with temporal variations of precipitation and groundwater level to estimate lag-time based on correlation coefficients calculated from auto-correlation function (ACF), cross-correlation function (CCF), and moving average (MA) at five sites. Landform and land-use/cover within 250 m radius of the monitoring wells(GW01, GW02, GW03, GW04, and GW05) at five sites were identified by land cover and digital map using Arc-GIS software. Long lag-times (CCF: 42-71 days and MA: 148-161 days) were calculated at the sites covered by mainly impermeable surfaces(GW01, GW03, and GW05) while short lag-times(CCF: 4 days and MA: 67 days) were calculated at GW04 consisting of mainly permeable surfaces. The results suggest that lag-time would be one of the good indicators to evaluate the effects of land-use/cover on estimating groundwater recharge. The results of this study also provide guidance on the application of statistical time series analysis to environmentally important issues on creating an urban green space for natural groundwater recharge from precipitation in the city and developing a management plan for hydrological disaster prevention.

An Analysis of Accessibility to Hydrogen Charging Stations in Seoul Based on Location-Allocation Models (입지배분모형 기반의 서울시 수소충전소 접근성 분석)

  • Sang-Gyoon Kim;Jong-Seok Won;Yong-Beom Pyeon;Min-Kyung Cho
    • Journal of the Society of Disaster Information
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    • 제20권2호
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    • pp.339-350
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    • 2024
  • Purpose: This study analyzes accessibility of 10 hydrogen charging stations in Seoul and identifies areas that were difficult to access. The purpose is to re-analyze accessibility by adding a new location in terms of equity and safety of location placement, and then draw implications by comparing the improvement effects. Method: By applying the location-allocation model and the service area model based on network analysis of the ArcGIS program, areas with weak access were identified. The location selection method applied the 'Minimize Facilities' method in consideration of the need for rapid arrival to insufficient hydrogen charging stations. The limit distance for arrival within a specific time was analyzed by applying the average vehicle traffic speed(23.1km/h, Seoul Open Data Square) in 2022 to three categories: 3,850m(10minutes), 5,775m(15minutes), 7,700m(20minutes). In order to minimize conflicts over the installation of hydrogen charging stations, special standards of the Ministry of Trade, Industry and Energy applied to derive candidate sites for additional installation of hydrogen charging stations among existing gas stations and LPG/CNG charging stations. Result: As a result of the analysis, it was confirmed that accessibility was significantly improved by installing 5 new hydrogen charging stations at relatively safe gas stations and LPG/CNG charging stations in areas where access to the existing 10 hydrogen charging stations is weak within 20 minutes. Nevertheless, it was found that there are still areas where access remains difficult. Conclusion: The location allocation model is used to identify areas where access to hydrogen charging stations is difficult and prioritize installation, decision-making to select locations for hydrogen charging stations based on scientific evidence can be supported.

Signal Analysis of Optical Biosensor to Detect Peroxide Using Electrically Controlled Release System (전기적 방출 조절 시스템을 이용한 광 페록사이드센서의 개발)

  • Min, Jun-Hong;Lim, In-Hee;Kim, Hyo-Han;Lee, Sang-Beak;Choi, Jeong-Woo;Lee, Won-Hong
    • Journal of Sensor Science and Technology
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    • 제6권1호
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    • pp.35-42
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    • 1997
  • The optical biosensor using the electrically controlled release of reactive reagent is developed for the detection of peroxide. Rapid degradation of polymer complex of PEOx and PMAA occurs as the applied current increases and thus released amount of HPA increases. The degradation velocity of polymer and the amount of HPA released are linearly proportional to the applied current. Peroxide is reacted with the released reagent by peroxidase and then the product, a fluorescent dimer DBDA, is formed. The monochromic light from light source (150W Xe arc ramp) excites the DBDA and the excited light is transmitted through an optical fiber to be detected by a photodiode array. The change of fluorescence intensity is related to the change of peroxide concentration. The peroxidase is entrapped in Ca-alginate get on the inner surface. The biosensor has the linear signal range of 0.025mM-10.mM peroxide. By applying the step function of peroxide, reproducibility of biosensor has been investigated. The mathematical model is constructed by the combination of enzyme kinetics with reactor flow model. Good agreement is obtained between the experimental result and model prediction in the sensor signal.

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Effects of Microstructures on the Toughness of High Heat Input EG Welded Joint of EH36-TM Steel (EH36-TM강의 대입열 EGW 용접부 저온 인성에 미치는 미세 조직의 영향)

  • Choi, Woo-Hyuk;Cho, Sung-Kyu;Choi, Won-Kyu;Ko, Sang-Gi;Han, Jong-Man
    • Journal of Welding and Joining
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    • 제30권1호
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    • pp.64-71
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    • 2012
  • The characteristics of high heat input (342kJ/cm) EG (Electro Gas Arc) welded joint of EH36-TM steel has been investigated. The weld metal microstructure consisted of fine acicular ferrite (AF), a little volume of polygonal ferrite (PF) and grain boundary ferrite (GBF). Charpy impact test results of the weld metal and heat affected zone (HAZ) met the requirement of classification rule (Min. 34J at $-20^{\circ}C$). In order to evaluate the relationship between the impact toughness property and the grain size of HAZ, the austenite grain size of HAZ was measured. The prior austenite grain size in Fusion line (F.L+0.1 mm) was about $350{\mu}m$. The grain size in F.L+1.5 mm was measured to be less than $30{\mu}m$ and this region was identified as being included in FGHAZ(Fine Grain HAZ). It is seen that as the austenite grain size decreases, the size of GBF, FSP (Ferrite Side Plate) become smaller and the impact toughness of HAZ increases. Therefore, the CGHAZ was considered to be area up to 1.3mm away from the fusion line. Results of TEM replica analysis for a welded joint implied that very small size ($0.8\sim1.2{\mu}m$) oxygen inclusions played a role of forming fine acicular ferrite in the weld metal. A large amount of (Ti, Mn, Al)xOy oxygen inclusions dispersed, and oxides density was measured to be 4,600-5,300 (ea/mm2). During the welding thermal cycle, the area near a fusion line was reheated to temperature exceeding $1400^{\circ}C$. However, the nitrides and carbides were not completely dissolved near the fusion line because of rapid heating and cooling rate. Instead, they might grow during the cooling process. TiC precipitates of about 50 ~ 100nm size dispersed near the fusion line.

A Study on the Characteristics and Distribution of the Time-Spatial Occurrence of Offensive Odors -Gangwon Province - (악취의 시공간적 발생 특성 및 분포도 분석 - 강원지역을 대상으로 -)

  • Kim, Byoung-Ug;Hyun, Geun-Woo;Bae, Sun-Hak;Hong, Young-Kyun;Lee, Yeong-Seob;Yi, Geon-Ho;Huh, In-Ryang;Choi, Seung-Bong
    • Journal of Environmental Health Sciences
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    • 제46권4호
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    • pp.376-387
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    • 2020
  • Objectives: This study is aimed at offering basic data for making plans for offensive odor management after researching offensive odor occurrence and characteristics in Gangwon Province. Methods: The data used in the study is based on offensive odor data analyzed by the Gangwon Institute of Health and Environment from 2012 to 2019. The data were reclassified by year, month, facility, and region to identify characteristics of occurrence. Finally, a distribution map of offensive odors was created using ArcGIS. Results: The highest monthly frequency of offensive odor occurrence falls in June, August, and July, and the summer season and third quarter are the highest. According to the latest eight-year data for Gangwon Province, complaints about offensive odors in county areas are more frequent than those in city areas. There are many offensive odor complaints in Wonju, Cheorwon, and Heongsung. The main offensive odor emission facilities are livestock and waste treatment (recycling) facilities. Complaints about offensive odors are relatively lower the Yeongdong area than Yeongseo area, which is considered to be the result of characteristics of land-sea breezes and geographical factors. Offensive odors from livestock facilities count for an average of 53.9% of the total, and the inadequacy rate of livestock facilities averages 36.9%. Conclusions: To maintain a clean environment in Gangwon Province, it is strongly recommended that an offensive odor reduction plan for livestock facilities be established. Areas with a high density of offensive odor occurrence should be identified and systematically managed with short- and mid-term measures. If offensive odors is managed using GIS, it is possible to identify the characteristics of occurrence by time and space and also by facility. In addition, since systematic data management is possible, it is believed that a rapid response to offensive odors, prediction of their spread, and efficient management are possible.

Insect Pest Resistance to Insecticides and Future Researches (해충의 살충제저항성과 금후대책)

  • Choi Seung Yoon
    • Korean journal of applied entomology
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    • 제22권2호
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    • pp.98-105
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    • 1983
  • The rapid increase in cases of insect resistance to insecticides indicates that the contribution of present chemical control practices inevitably leads to exhaustion of available insecticide resources against key insect species. Now the problem of insecticide resistance exists worldwide among insects and mites affecting field crops and animals including human beings, ranging from minimal or absent in some developing countries, where use of insecticides has been low, to extremely severe in many developed countries. Since the occurrence of insect resistance to insecticides was firstly recognized in 1908, the increase in recent decades has been almost linear and now the number of species of insects and acarines in which resistant strains have evolved have been increased to a total of 432. Of these, $261(60\%)$ are agricultural importance and $171(40\%)$ of medical/veterinary importance. The phenomenon of insecticide resistance is asserting itself as the greatest challenge to effective chemical control of many important insect pests. Resistance of insects to insecticides has a history of nearly 80 years, but its greatest increase and its strongest impact have occurred during the last 40 years following the discovery and extensive use of synthetic organic insecticides and acaricides. The impact of resistance should be considered not only in terms of greater cost of pest control due to increased dosages and number of applications but also in terms of the ecological disruption of pest-beneficial species density relationships, the loss of investment in the development of the insecticides concerned, and socio-economic disruption in agricultural communities. Despite its grave economic consequences, the phenomenon of insecticide resistance has received surprisingly little attention in Korea. Since the study of insecticides started firstly in 1963, many entomologists have been concerned with this study. According to their results, some of the rice pests and some of the mites on orchard trees, for example, have developed worrisome level of resistance in several areas of this peninsula. With many arthropods, considerable advances in the developed countries have been made in the study of the biochemical and physiological mechanisms of resistance. Progress involves the biochemical characteristics of specific defense mechanisms, their genetics, interactions, and their quantitative and qualitative contribution to resistance. But their studies arc still inadequately known and relatively little have been contributed in terms of unique schemes of population management in achieving satisfactory pest control. It is apparent that there is no easy solution to resistance as a general phenomenon. For future challenging to effective control of insect pests which are resistant to the insecticides concerned, new insecticide groups with distinctly novel mode of action are urgently needed. It is clear, however, that a great understanding of the factors which govern the intensity of selection of field population for resistance could lead to far more permanently successive use of chemicals within the framework of integrated pest management than heretofore practiced.

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