강원도 치악산 계류에서 하루살이과에 속하는 가는무늬하루살이와 무늬하루살이의 온도와 연관된 생활사 적응에 대하여 연구하였다. 하루살이 개체군의 고도분포에 따라 3개의 조사지점(상류와 중류지점: 가는무늬하루살이; 하류지점: 무늬하루살이)을 선정하였다. 채집은 1997. 2~1998. 1 동안 월 1회 실시하였고, 우화기에는 월 2회 실시하였다. 수온은 1997. 5~1998. 1 동안 시간대로 모니터링 하였다. 결과로서, 3개의 조사지점은 서로 다른 온도역(평균온도 상류: 9.39°C; 중류: 10.38°C; 하류: 12.70°C)을 나타냈다. 체장과 유충단계의 분석 결과 두 종 모두 명백히 연 1세대였고, 각 개체군은 2개의 무리(cohort)를 포함하였다. 우화는 늦은 5월부터 늦은 6월까지 일어났지만 하류로 갈수록 일렀다. 유충의 충원은 우화기(여름형)와 그 5~6개월 이후(겨울형)에 시작되었다. 이처럼 2회에 걸친 유충의 충원에 대하여 알의 휴면 또는 무성생식이 원인으로 작용하는 것으로 가정되었다. 상류와 중류에서 가는무늬하루살이의 총 적산온도는 각각 2380DD와 2668DD였고, 하류에서 무늬하루살이는 3220DD였다. 가는무늬하루살이의 경우 연평균수온이 1°C 내려감에 따라 알의 부화는 약 22일, 평균 유충성장은 약 15일 지연되는 것으로 추정되었다. 가는무늬하루살이는 냉온에 적응된 생활사 양상을 나타냈고, 다른 한국산 및 일본산 근연종과 비교하여 종내 및 종간 생활사 적응에 대하여 추가로 논하였다.

사과원에서 사용되는 살비제 5종, 살충제 4종, 살균제 6종올 추천농도로 희석하여 점박이응애와 긴털이리응애에 대한 상대독성을 엽침지법으로 실험실에서 조사하였다. Dicofol은 점박이응애와 긴털이리응애에 대해 독성이 매우 강하였으며, 이들의 난에 대해서도 각각 46%와 40%의 致死效果가 있었다. Abamectin 용액에 침지된 긴털이리응애 암컷성충의 사망율은 무처리와 차이가 없었으나 점박이응애의 암컷성충은 24시간 이내에 모두 사망하였다. Tetradifon, Clofentezine, Hexythiazox등 3종의 살란성 살비제는 점박이 응애의 난에 대해서는 90%이상의 살란효과를 나타내었으나 긴털이리응애 난의 부화에는 아무런 영향이 없었다. Teflubenzuron, Triflumuron, Diflubenzuron, lmidacloprid 등 4종의 살충제와 Propineb, Fenarimol, Polyoxin-B.captan 등 3종의 살균제는 긴털이리응애 암컷성충에 대해 살비효과가 없었으며, Chlorothalonil, Nuarimol . Mancozeb, Folpet 등 3종의 살균제도 23% 이하의 낮은 살비효과를 나타내었다. 이상과 같이 긴털이리응애 난이나 암컷성충에 저독성을 나타내는 4종의 살충제와 4종의 살비제 및 6종의 살균제는 사과원 병해충 종합관리체계에서 긴털이리응애와 함께 이용될 수 있을 것으로 생각된다.

The premiums on closed-end country funds tend to move in tandem, but do not move together with premiums on domestic closed-end funds. After controlling for foreign maket fundamentals, changes in the stock price of country funds co-move with U.S. market returns, but changes in their net asset values do not. An index of changes in country fund premiums explains cross-sectional stock returns in the U.S. market, particularly for small firms. Collectively, these findings suggest U.S. stock prices are affected by market-wide sentiments which are reflected in closed-end country fund premiums.

변색미(變色米) 발생(發生)에 관여(關與)하는 병원균(病原菌)과 해충을 분류동정(分類同定)한 결과(結果) 해충으로는 허리노린재과(科)에 속하는 Leptocorisa oratorius가 우점종(優占種)이었고 노린재과(科)인 Menida varipennis. Stollia ventralis 및 Nezara viridula 등이 관여(關與)하였으며 병원균(病原菌)으로는 Drechslera oryzae. Curvularia lunata, Trichoniella padwickii, Sarocladium oryzae, Alternaria tenuis 및 Fusarium solani 등이 관여(關與)하였다. 병원균(病原菌)과 해충의 복합발생시(複合發生時)에 변색미발생(變色米發生)이 더 심하였고 병원균(病原菌)만의 발생시(發生時)는 변색미(變色米) 발생(發生)에 주로 영향(影響)을 미쳤으며 노린재류만의 발생시(發生時)는 수량감수(收量減收)에 더 큰 영향(影響)을 주었다. 그리고 노린재류에 의한 벼 유숙기간(乳熟期間)의 흡즙(吸汁)은 병원균침입(病原菌侵入)을 조장(助長)하여 벼의 질적(質的) 변화(變化)와 양적(量的) 감소(滅少)에 크게 영향(影響)하였다.

In crop breeding program, information about genetic dissimilarity on breeding resources is very important to corroborate genealogical relationships and to predict the most heterozygotic hybrid combinations and inbred breeding. This study aimed to evaluate the genetic variation in Kenyan sunflower breeding lines based on simple sequence repeat (SSR). A total of 83 alleles were detected at 32 SSR loci. The allele number per locus ranged from 2 to 7 with an average of 2.7 alleles per locus detected from the 24 sunflower accessions and the average value of polymorphic information contents (PIC) were 0.384. A cluster analysis based on the genetic similarity coefficients was conducted and the 24 sunflower breeding resources were classified into three groups. The principal coordinates (PCoA) revealed 34% and 13.38% respectively, and 47.38% of total variation. It was found that the genetic diversity within the Kenyan sunflower breeding resources was narrower than that in other sunflower germplasm resources, suggesting the importance and feasibility of introducing elite genotypes from different origins for selection of breeding lines with broader genetic base in Kenyan sunflower breeding program.

Clogging of the filter media which is brought by physical, chemical, and biological factors tend to reduce the lifespan of filters and remains a challenge. In this study, a laboratory column test method was used to investigate the evolution of physical and biological clogging in a non-vegetated filter media system with layers of sand, gravel, and woodchip. Blank column tests using either sand or gravel were conducted and investigated. Several column setups with varying arrangements and particle sizes of sand and gravel were also prepared to identify the best filter media combination that is least susceptible to clogging without compromising the treatment capacity. Artificial stormwater runoff was introduced in the system at a specific hydraulic loading rate (HLR) and influent characteristics. The degree of clogging was quantified by monitoring the variations in the hydraulic head at different levels of the columns. Water samples were also collected, tested, and analyzed at the end of each test run in order to measure the treatment efficiency of the filter. The insights and results of this study can justify the physical and biological clogging formation in filter media and therefore be used to suggest some filter media particle size modifications that can help to improve the sediment removal and treatment performance. Moreover, it can also aid to reduce the maintenance frequency and costs of a stormwater filter system.

Controllable transgenic expression systems in transgenic animal model are valuable to the development of therapeutic approaches in human medical fields. The aim of this study was to 1) produce a transgenic cloned dog using inducible tetracycline vector system, and 2) investigate whether the transgenic cloned dog could be induced the transgene expression using doxycycline (Doxy). Canine fetal fibroblasts were infected with retroviral vectors designed to express the enhanced green fluorescent protein (eGFP) gene under the control of tetracycline-inducible promoter. For somatic cell nuclear transfer (SCNT), nucleus of an in vivo matured oocyte was removed and an eGFP expressed cell cultured with 1 ㎍/㎖ of Doxy was injected. After electrical fusion and chemical activation, the reconstructed embryos were transferred to a recipient and pregnancy diagnosis was performed by ultrasonography. Experiment I evaluated the mean fluorescence intensity (MFI) of infected cells while the cells were cultured in the presence of 1 ㎍/㎖ of Doxy for 5 days, and then in the absence of Doxy for 7 days using fluorescence-activated cell sorter. Experiment II was designed to produce an eGFP controllable transgenic cloned dog via SCNT. For verification of transgenic dog, experiment III was performed Southern Blot analysis and observation in vivo regulation of eGFP expression in the cloned dog treated with 100 ㎎/㎏ of Doxy every 2 days for 2 weeks under ultraviolet light. In experiment IV, western blot was used to detect eGFP increase and decrease in skin tissues of transgenic dog under the presence or absence of Doxy. In the results of experiment I, the MFI for infected cells was rapidly increased to approximately 42.3 times after 3 day-treatment compared to pre-treatment and quickly decreased 3 days after ceasing the treatment. In experiment II, a total of 203 embryos were transferred to nine recipients and three pregnant delivered three pups (Tet-on eGFP 0, Tet-on eGFP 1, and Tet-on eGFP 2) by C-sec and Tet-on eGFP 2 among them is still alive. All cloned pups were genetically identical to the donor cell. Tet-on eGFP 2 showed an apparent in vivo eGFP expression on her body after Doxy administration in experiment III. The result of Sothern blotting showed that the transgene insertion was detected from the three cloned dogs and all organs of Tet-on eGFP 1. Experiment IV indicated that a robust eGFP expression in skin tissue of Tet-on eGFP 2 rapidly increased after Doxy treatment and gradually decreased to basal level on 9 weeks after ceasing the treatment. In conclusion, we report here for the first time an inducible transgenic system in canine species and it can stably induce the transgene expression at intended time. This study has demonstrated the capacity to generate transgenic model dog which could regulate the transgene and it would contribute to human medical research fields.

"Early Valley", is an early maturing potato cultivar with high yield potential. "Early Valley" is a clonal selection resulting from the cross between 'Suncrisp' and 'A87109-10'. It has medium plant height and light green foliage. "Early Valley" has medium flowering habit and white flowers. Tubers are smooth, yellow skin, light yellow flesh, round tuber shape, medium eye depth, and medium dormancy and good keeping quality. It has stable yield under wide range of climatic conditions. "Early Valley" is resistance to late blight, but moderately susceptible to common scab and hollow heart. This cultivar is also resistant to potato rotting at harvesting during the raining season. "Early Valley" has high level of antioxidant activity (about three times higher) and vitamin C (higher by 40%) than the 'Superior'. This cultivar has high level of tuber uniformity and capable of yielding 36.56 t/ha which is 17.07% higher than the control potato cultivar 'Superior' under optimum agronomical practices.

Bovine embryos produced by in vitro maturation, feretilization and development was examined for presevation and transfer. The fertilization medium used BO medium with 5 mM/ caffeine and 10/ heparin and adjusted to a pH of 7.2 to 7.4. The final concentration of spermatozoa was adjusted to 1 cells/ motile sperm during fertilization in vitro. At 8~10 hrs after insemination, the oocytes were transferred into CR1aa medium and cultured for 7 days. Embryos were preserved by vitrification method for transfer. When the embryos of early, blastocyst and expanded blastocyst stages were frozen-thawed, the proportions of embryos with normal morphology 83.6, 88.1 and 85.2%. (중략)

The purpose of this is to investigate the effects of vitrification in open pulled straws (OPS) on in vitro survival of porcine embryos. Blastocysts were produced by in vitro fertilization of slaughterhouse-derived, in vitro matured oocytes with frozen-thawed boar semen, and subsequent culture on granulosa cell monolayer. After frozen-thawing, embryos were culture in NCSU-23 medium with 5 mM hypotaurine, 4 mg/ BSA and 10 ng/ for 48 hrs to survival tests. When blastocysts were frozen-thawed by OPS methods, the embryos with normal morphology were 32.1, 34.5 and 38.9 % in early blastocyst, blastocyst and expanded blastocyat stages. The rates of partial damaged embryos were significantly (P<0.05) higher in early biastocysts than expanded blastocysts. In another experiment, the embryos frozen by OPS methods were cultured for 48 hrs for survival and developmental rates in vitro. The proportions of embryos hatched were 11.8, 20.2 and 33.3% in embryos frozen-thawed at stages of early blastocyst, blastocyst and expanded embryos. On the other hand, The proportions of embryo with normal morphology after culture were 23.5, 25.0 and 33.3% in embryos frozen-thawed at stages of early blastocyst, blastocyst and expanded embryos. These finding indicate the possible broader application for OPS methods that this procedure described is relatively harmless, that it can be used for blastocysts of different developmental stages.