검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 187

        61.
        2010.05 구독 인증기관·개인회원 무료
        In an effort to gain a better understanding of the nature of the population genetic structure of the pest insect, Spodoptera litura (Lepidoptera: Noctuidae), tobacco cutworms were collected from six Korean and five Chinese localities and their mitochondrial A+T-rich region and nuclear internal transcribed spacer 2 (ITS2) regions were cloned and sequenced. A total of 106 A+T-rich region haplotypes and 92 ITS2 sequence types were obtained from 158 individuals. Compared to the preliminary mitochondrial COI gene sequence data that provided all identical sequence types in all samples, the A+T-rich region and nuclear ITS2 are highly variable. Overall, a low level of genetic fixation in the A+T-rich region (FST = 0 ~ 0.02965) and nuclear ITS2 (FST = 0 ~ 0.34491), and no discernable isolated population was noted to exist among most S. litura populations. The presence of a majority of within-population variations, rather than variations among populations or between China and Korea, indicates that the S. litura populations are composed of heterogeneous individuals. The fixation index at hierarchical level of among regions shows no significance, suggesting that the S. litura populations in both Korea and China are profoundly interrelated with one another. This finding is in accord with the current knowledge that S. litura has sufficient flight capacity for dispersal.
        62.
        2009.10 구독 인증기관·개인회원 무료
        Ecological changes, both man-made and natural, have changed the landscape of the Republic of Korea following the end of Japanese occupation at the end of World War II (1939-1945). During the Japanese occupation, forested hillsides were cleared and wood products shipped to Japan, leaving the hills and mountains largely covered by grasses and other shrub vegetation. Following WWII, the country of Korea was divided into North and South Koreas, with North Korea under communist powers, while South Korea was established as a democratic government. In South Korea poverty was rampant and local populations scavenged for wood for cooking and heating during the cold winters. Just as economic conditions were increasing, South Korea was attached by North Korea, beginning a long drawn-out conflict from 1950 to the summer of 1953, whereby an armistice was signed and an often uneasy peace between the two countries continues today. Again, the Republic of Korea emerged from a War as an impoverished country with treeless country sides, hills, and mountains. In the 1960’s, president Chung-Hee Park established a tree planting policy to reestablish long-ago lavish forested mountains and hillsides that make up more than 70% of the South Korean landscape. Today, mountains and hillsides are generally not used for agriculture and are completely forested, with planted groves and volunteer trees ranging in age from 10-50 years. These forested areas have led to increased protection for large and small mammals and birds, increasing the potential for zoonotic pathogens that there ectoparasites harbor to be transmitted to man during work and leisure activities. While forested areas provided an expanded habitat for some animals, agriculture expanded and modernized, resulting in short-cut grasses on banks separating much of the rice paddies, orchards, ditches, and dry-land farming that increased competition for small mammal habitat. As a result of increased surveillance of small and large animals and their ectoparasites, the increased prevalence of known pathogens and identification of new pathogens, especially those harbored by ticks, has demonstrated the presence of tick-borne encephalitis, several species of spotted fever group Rickettsia, and a host of other zoonotic diseases in wild animals, their ectoparasites, and man. As tick-borne diseases are not reportable diseases in Korea, the extent and impact on civilian and military populations is unknown as diagnoses are often likely sought for the wrong pathogen. While agriculture modernized, military training sites largely consist of unmanaged lands with tall grasses that are conducive to large and small mammal populations, which are host to a number of zoonotic diseases, e.g., hantaviruses, scrub typhus, murine typhus, leptospirosis, tick-borne encephalitis, spotted fever group rickettsial pathogens, Lyme disease, bartonellosis, etc. that impact on military populations training in those areas. The impact of training sites habitat modification has not been assessed, but for many sites is impractical. To reduce health risks of vectorborne diseases, the US Army has established better housing (tents to barracks with screened windows and air conditioning) at some field training sites, reducing the potential for the transmission of mosquito-borne pathogens (malaria and Japanese encephalitis virus). The increased use of permethrin-treated all climate uniforms (ACUs) and repellents, also reduce the potential for transmission of mosquito-, tick-, mite-, and flea-borne pathogens. However, training conditions at some field training sites remain largely unchanged, with personnel working and sleeping in tents that abut to forested areas where animals and their ectoparasites are present. While some training and maneuver sites are well planned for weapons qualifications of wheeled and tracked vehicles, others sites are in areas of unmanaged lands which are rodent infested. Increased surveillance by the 65th Medical Brigade not only provides a baseline and relative distribution for vector-borne diseases in Korea, but also provides disease trends and risk assessments that are necessary for protecting US military personnel training in Korea.
        63.
        2009.08 구독 인증기관·개인회원 무료
        This study was conducted on both Grassland & Forage Research Center, NIAS, Cheonan(Central area) and Sancheong(southem area) from 2005 through 2008, in order to evaluate the effect of various cultivation methods on productivity of organic com silage. Treatments included five cultivation methods(conventional, normal organic, strip seeding, early seeding, late seeding) using a com silage(P3156)-crimson clover(Contea) double crop system. Crimson clover was used for either cover crop or green manure in this experiment.
        64.
        2009.08 구독 인증기관·개인회원 무료
        This experiment was conducted to determine the effects of applying level of pig slurry on the characteristics of runoff and leaching water in lysimeter. Treatments were broken down into five treatments such as non-chemical fertilizer, chemical fertilizer (200㎏ N/㏊) and pig slurry (200, 400, 600㎏ N/㏊), and 3-time-repeated randomized complete block design was fulfilled. The concentrations of NO₃-N was raised(p<0.05) in proportion to the applying level of pig slurry. NO₃-N concentration of leaching water collected from soil depth 20㎝ and 40㎝ was intensified as the applying level of pig slurry was higher (p<0.05) in pig slurry 600㎏ N/㏊ application. In conclusion, pig slurry at the volcanic ash soil in Jeju area can replace the chemical fertilizer as it is tested that applying 200㎏ N/㏊ of pig slurry and chemical fertilizer show the same productivity of sorghum×sudangrass hybrid. But more than 200㎏ N/㏊ of pig slurry may not be appropriate because it may contaminate the runoff and leaching water even though it may increase for the forage productivity.
        65.
        2009.08 구독 인증기관·개인회원 무료
        The experimental work was conducted to investigate the effects of the application level of composted cattle manure (CCM) on forage productivity using whole crop barely (WCB)-whole crop rice (WCR) double cropping system for 3 years. Main plot was consisted of application level of CCM such as 150%, 200% and control plot. The total DMY of forages under WCB and WCR in treatment of CF significantly decreased as compared with that of treatment of CCM 150%. However, NDF, ADF and CP content of WCB and WCR were hardly influenced by CCM application.
        66.
        2009.08 구독 인증기관·개인회원 무료
        This experiment was carried out to find out the optimum variety of com hybrids and to find out alternative crops in the rice black-streaked dwarf virus(RBSDV) prevalent area. Productivity of 4 Korean improved and 6 introduced com hybrids and RBSDV infection rate were tested for 3 years in both Cheonan(middle part of Korea) and Gochang(southern part of Korea). Percentage of RBSDV diseased plants differed depending on the hybrid and region.
        67.
        2009.05 구독 인증기관·개인회원 무료
        We assessed the environmental risk of herbicide resistant transgenic rice (Protox) on non-target herbivore, grasshoppers (Oxya japonica japonica Thunberg). We conducted life-history experiments of grasshoppers with measuring their body weight, body length, eating amount, and feces amount between non-transgenic rice (nTR; Dongjin rice) and transgenic rice (TR; Protox rice) under laboratory conditions (Temp. 25Ð, R.H. 50-70%, Photoperiod L16:D8) in 2007. The growth of grasshoppers appeared to increase at each measuring date. We also compared the growth rate of grasshoppers between nTR and TR to examine the transgenic impact on the herbivore and we found there was no statistically signifi cant difference between the two plant types (P>0.05). We found that body weight and body length for grasshoppers were highly correlated at each of the two types of plants, nTR (0.962) and TR (0.960). The correlation of eating amount and feces amount of grasshoppers were higher nTR (0.830) than TR (0.782). The energy effi ciency of the grasshopper was not a signifi cant between nTR and TR (P> 0.05). But the molt timing of the grasshoppers for TR difference was faster than for nTR. Conclusively life-history of the grasshoppers but molt timing was not a signifi cant difference between nTR and TR. Therefore, we could conclude there was not any environment risk on herbivore from our result.
        68.
        2008.10 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        We present an optical-infrared photometric study of galaxies in six nearby clusters of galaxies at z=0.041∼0.098 (A1436, A1773, A1809, A2048, A2142, and A2152). Using BV I photometry obtained at the Bohyunsan Optical Astronomical Observatory and JHKS photometry extracted from the 2-Micron All-Sky Survey catalog, we investigate the colors of galaxies in the clusters. Using the (B − V ) versus (I −KS) color-color diagrams in comparison with the simple stellar population model, we estimate the ages and metallicities of bright early-type member galaxies. Early-type galaxies in each cluster show the color-magnitude relation. Ages and metallicities of early-type members show little dependence on their velocity dispersions. Mean ages of early-types in the clusters range from 3 Gyr to 20 Gyr, showing a large dispersion, and mean metallicities range from Z = 0.03 to 0.05 above the solar value, showing a negligible dispersion.
        4,200원
        70.
        2008.05 구독 인증기관·개인회원 무료
        We determined the complete mitogenome of the oriental mayfly, Ephemera orientalis (Ephemeroptera: Ephemeridae) and the dragonfly Davidius lunatus (Odonata: Gomphidae). The 16,463-bp long E. orientalis and the 15,912 bp long D. lunatus mitogenome contains gene arrangement and content identical to the most common type found in a diverse insect order. Most individual E. orientalis and D. lunatus mt genes were well within the size found in the respective genes of other insects. The initiation codon for the D. lunatus COI gene was typical as ATA, whereas no typical start codon was found in the start region of E. orientalis COI gene. The A+T-rich regions of both mitogenomes have a few unusual feature. The A+T-rich region of E. orientalis contains a tandem repeat composed of two identical copies of 55 bp long, whereas that of D. lunatus contains a tandem repeat composed of duplicated identical 261-bp copies and one partial copy of the repeat. Also, the A+T-rich region of E. orientalis contains a single sequence and that of D. lunatus contains nine sequences, along with the tandem triplicate sequences, that has the potential to form stem-and-loop structures, flanked by the conserved sequences, “TA(A)TA” at the 5’ end and “G(A)nT’ at the 3’ end. Furthermore, the A+T-rich region of D. lunatus contains two tRNA-like structures, tRNALeu(UUR)-like sequence and tRNATyr-like sequence that have proper anticodon TAA and clover-leaf structure that were previously found in the hymenopteran insects.
        71.
        2008.05 구독 인증기관·개인회원 무료
        A new species, Hatchiana n. sp., is confirmed by morphological and molecular data. The genus Hatchiana Fender, 1966 belonging to Podabrini LeConte, 1881 is distinguished by the shape of tarsal claws: all tarsal claws with blunt tooth in both sexes. The genus was recognized as a subgenus of Podabrus Westwood, 1838. Recently, however, Hatchiana was suggested as separated genus. The genus Hatchiana was known as 12 species in Palaeartic region including three species from Korea. In this study, we found Hatchiana n. sp. from several areas of Taean-gun, Chungcheongnam-do, Korea. This new species is different from closely relative species, Hatchiana jirisanensis (Kang & Kim, 2000) by following morphological characters: size of compound eye, length of antennae, shape of pronotum, shape of scutellum, and shape of aedeagus. Also, we compare the DNA barcoding region (the former region of CO1 gene) between these two species as molecular characters. In result, Hatchiana n. sp. is distinct from Hatchiana jirisanensis Kang & Kim by discrepancy of three percents in CO1 sequence. Therefore, the Korean Hatchiana is confirmed as four species, adding Hatchiana n. sp.
        75.
        2005.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        방사성 폐기물 핵종 재고량 평가에 필요한 핵종분석을 위하여 다양한 매질의 방사성 폐기물 시료로부터 및 의 분리에 관한 연구가 수행되고 있다. Ni은 음이온교환 수지와 Sr-Spec 추출 크로마토그래피 수지로 Re(의 대용물), Nb, Fe 및 Sr을 차례로 분리하는 과정에서 Ca, Mg, Al, Cr, Ti, Mn, Ce, Na, K 및 Cu와 함께 회수되었다. 본 연구에서는 Ni의 선택적 분리기술을 확립하기 위하여 Ni-Spec 추출 크로마토그래피 및 양이온교환수지법으로 이들의 분리거동을 비교하였다. 또한 Ni의 정제와 기체비례계수법으로 방사능을 측정하기에 적합한 계측시료 준비를 위하여 ammonium 및 tartaric 에서 dimethylglyoxime(DMG)에 의한 Ni의 침전거동을 조사하였다 원자력발전소로부터 채취한 폐이온교환수지 시료 용해용액의 화학조성을 모사하여 만든 모의 폐이온교환수지 용액을 사용하여 Re, Nb, Fe 및 Sr 분리과정을 거쳐 최종적으로 분리한 Ni의 회수율은 이었다. 또한 tartaric 에서 DMG에 의한 Ni의 회수율은 이었다.
        4,000원
        79.
        1989.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        1998년 7월부터 10월까지 약 4개월간 질병매개모기 및 뇌염다발지역인 전라남도 영암군 덕진면 소재 약 30,000M2의 자연수답을 선정, 이에 서식하는 질병매개모기인 중국얼룩날개모기(Anopheles sinensis)와 작은빨간집모기(Culex tritaeniorhynchus)를 대상으로 포식천적어송사리(Aplocheilus latipes) 및 왜몰개(Aphyocypris chinensis)방사와 미생물제제(Bacillus thuringensis H-14)를 병합처리하여 방제효과를 조사하였다. 포식천적어송사리가 0.6fish/TEXM2/TEX가 존재하는 논에서는 7월부터 8월까지 55.0~57.6%의 자연 방제가 이루어졌으며, 한 표본당 평균 10마리 이상으로 증가될 때 미생물제제(B.t. H-14)를 1Kg/ha의 농도로 처리한 결과, 24시간후 100%의 방제를 보였으며, 10월 11일 본 실험이 끝날 때까지 98%의 방제율을 유지하였다. 천적어가 존재하지 않는 논에서는 수면 1TEXM2/TEX 당 1.5마리의 비율로 포식어(Aphyocypris)를 방사한 결과 9월 21일(방사후 2주)까지 88.2~96.7%의 만족할 만한 방제율을 유지하였다. 천적어가 존재하지 않는 또 다른 논에서 미생물제제(B.t. H-14)를 1Kg/ha의 농도로 단독 처리한 결과, 24시간 후 100%의 방제율을 보였으나, 7일 후에는 개체군밀도의 회복현상을 나타내었으며 B.t.(H-14) 2차 처리후 모기유충의 개체군밀도를 억제할 수 있었다.
        4,000원
        80.
        2017.12 KCI 등재 서비스 종료(열람 제한)
        Interferon-stimulated gene 15 (ISG15) is known to interfere with viral replication and infection by limiting the viral infection of cells. Interferon-stimulated gene 15 (ISG15) interferes with viral replication and infectivity by limiting viral infection in cells. It also plays an important role in the immune response. In this study, tissue-specific expression of ISG15 in healthy rock bream samples and spatial and temporal expression analysis of rock bream ISG15 (RbISG15) were performed following rock bream iridovirus (RSIV) infection. RbISG15 expression was significantly higher in the eye, gill, intestine, kidney, liver, muscle, spleen, and stomach, but low in the brain. There were particularly high levels of expression in the liver and muscle. RbISG15 expression was also examined in several tissues and at various times following RSIV infection. ISG15 expression increased within 3 h in the whole body and decreased at 24 h after infection. In addition, temporal expression of several tissues following RSIV infection showed a similar pattern in the muscle, kidney, and spleen, increasing at 3 h and decreasing at 72 h. These results suggest that ISG15 plays an important role in the immune response of rock bream. Overall, this study characterizes the response of RbISG15 following RSIV infection.
        1 2 3 4 5