The present study investigated the effects of different seeding rates on growth characteristics and seed productivity of the “Kowinearly” cultivar of Italian ryegrass (Lolium multiflorum Lam.) in paddy fields. Sowing Kowinearly in paddy fields under growing rice at the rates of 20, 30, 40, and 50 kg/ha resulted in seed yields of 1.57, 1.92, 2.06, and 2.09 ton/ha, respectively. Seed yield of Kowinearly was the highest at a seeding rate of 50 kg/ha (p<0.05), at which the cultivar was able to survive in winter and the weed ratio was low. Under these conditions, most growth characteristics such as winter survival (85%), weed ratio (10%), stems per square meter (1,006) were superior than those sown at other seeding rates (p<0.05). In addition, it has been reported that the economic efficiency of the 50 kg/ha seeding rate was higher than that of the other seeding rates.

This study was conducted to determine the relationship between stand and soil environmentalfactors, and soil respiration rates at various levels of basal area in a 40-year-old natural redpine(Pinus densiflora S. et Z.) stand in southern Korea. Soil respiration rates were measuredmonthly using an infrared gas analyzer system from six basal area treatments between 21.4 m2ha-1 and 46.7 m2 ha-1 for one year. Soil respiration at various levels of basal area showed aclear monthly variation, which had a similar pattern to soil temperature. The mean annualsoil respiration rates were positively correlated with increasing basal area(r=0.86, p<0.05),aboveground tree carbon (C) storage(r=0.85, p<0.05) and needle litter C fluxes(r=0.88, p<0.05),but the rates were not correlated by the soil environmental factors(p>0.05) such as the meanannual soil temperature, soil water content, soil pH, and soil organic C content during the studyperiod. The results indicate that it is important to understand the role of stand attributes in themean annual soil respiration rates in a stand level.

Effect of heavy metals (Cd, Cu, Zn) on the survival and population growth rates (PGR) of marine rotifer, Brachionus plicatilis were examined. B. plicatilis were exposed to Cd, Cu and Zn for 24 h to determine their survival and 72 h to determine their PGR. Survival rates in the control groups were greater than 90%. They were decreased with increasing concentrations of Cd, Cu and Zn. Survival rates were reduced in a concentration-dependent manner. Significant reduction in survival rates after exposure to Cd, Cu and Zn at concentration greater than 40.00, 0.13 and 10.00 mg L-1, respectively. PGR in the control groups were greater than 0.50. They were decreased with increasing concentrations of heavy metals. PGR were reduced in a concentrationdependent manner. Significant reduction in PGR after exposure to Cd, Cu and Zn occurred at concentration greater than 12.5, 0.06 and 1.00 mg L-1, respectively. The order of heavy metal toxicity based on PGR was Cu>Zn>Cd, with EC50 (50% Effective Concentration) values of 0.12, 6.15 and 21.41 mg L-1, respectively. The lowest-observed-effective-concentrations (LOEC) of PGR after exposure to Cd, Cu and Zn were 12.50, 0.06 and 1.00 mg L-1, respectively. The No-observedeffective- concentrations (NOEC) of PGR after exposure to Cd, Cu and Zn were 6.25, 0.03 and 0.01 mg L-1, respectively, in marine ecosystems have toxic effects on PGR of B. plicatilis. These results suggest that the PGR of B. plicatilis are useful tool to assess the effect of heavy metals on primary consumers in marine natural ecosystems.

본 연구는 뿌리부추를 시설하우스에서 재배할 경우 여름철 고온기 하고현상(Summer depression)을 방지하기 위하여 차광막을 하우스 내부 또는 외부에 설치하여 차광정도를 달리하면서 생육 및 수량에 미치는 영향을 조사하기 위하여 수행되었다. 2015년 하우스 내부에 무차광, 35, 55, 75, 95% 차광막을 설치하여 정식 후 20일 째 되는 날에 최종 출현 정도를 조사한 결과, 무처리, 35 및 75% 차광에서 98% 출현하였고, 55 및 95% 차광에서 100% 출현하였다. 차광 정도와는 상관없이 모든 처리에서 최종 출현은 양호하였다. 하우스 내외부에 차광막을 설치했을 경우, 2년간 평균 생중량(Fresh weight) 은 75% 차광에서 6,323kg/10a으로, 무차광, 35%, 55%, 95% 차광보다 각각 5.0배, 1.8배, 1.1배, 1.7배 높았다. 하우스 외부에 차광막을 설치할 경우 생중량은 75% 차 광에서 684g으로, 55%, 95% 차광보다 1.1배, 1.8배 높았다. 건중량(Dry weight), 건물율(Percentage of dry matter), 엽수(No. of leaves), 분얼수(No. of branches), 초장(Plant height), 근장(Root length) 등 분석결과 75% 차광이 다른 차광 보다 통계적으로 유의하게 높거나 절대적 수치가 높게 측정되어 중부지역에서 뿌리부추를 재배 할 경우에는 75% 차광이 가장 적합한 것으로 판단 되었다.

This study aimed to evaluate the quality characteristics of wheat-Makgeolli (WM), a traditional Korean cereal alcoholic drink, using three varieties of wheat, namely Jokyoung (JK), Baegjoong (BJ) and Keumkang (KK). Samples of WM brewed from 100%, 85% and 70% milling rates of the three Korean wheat cultivars were analyzed for alcohol, pH, coloring degree, total acids, soluble solid, free sugars, and organic acids. As the milling rates in wheat decreased, total sugar content in WM increased while the pH of all samples decreased. The WM exhibited 0.95~1.27% in acidity, 10.2~12.5 °Brix in total sugar, and 14~16% in alcohol content. The most organic acids in WM was lactic acid, ranging in all the samples from 85.3~650.3 mg%. The results showed that BJ under a 70% milling rate had the highest reducing sugar contents and 15.97% in alcohol content. The carbohydrate content increased with the milling rate of wheat. Resulting in a positive correlation between carbohydrate content of wheat and total acids, reducing sugars (p<0.001), and alcohol content (p<0.05) in WM. Total sugar content is positively correlated with alcohol and reducing sugar content (p<0.001). Considering the yield, the milling rates will be adjusted to raw material prices.

The present study deals with the effects of micro-alloying elements such as Ni, V, and Ti on the recrystallization behavior of carbon steels at different strain rates. Eight steel specimens were fabricated by varying the chemical composition and reheating temperature; then, a high-temperature compressive deformation test was conducted in order to investigate the relationship of the microstructure and the recrystallization behavior. The specimens containing micro-alloying elements had smaller prior austenite grain sizes than those of the other specimens, presumably due to the pinning effect of the formation of carbonitrides and AlN precipitates at the austenite grain boundaries. The high-temperature compressive deformation test results indicate that dynamic recrystallization behavior was suppressed in the specimens with micro-alloying elements, particularly at increased strain rate, because of the pinning effect of precipitates, grain boundary dragging and lattice misfit effects of solute atoms, although the strength increased with increasing strain rate.

In pig, more than half of the recovered cumulus cell-oocyte complexes (COCs) have one or two layers of cumulus cells and are considered morphologically poor. If we could take full advantage of these poor quality COCs, we could potentially improve the efficiency of in vitro embryo production. During in vitro maturation, although some maturation factors are transmitted bidirectionally between the oocyte and cumulus cells of the same COC, transmission also occurs between different COCs. We hypothesized that morphologically poor COCs fail to undergo complete oocyte maturation due to their insufficient secretion of maturation factors. Here, we investigated whether co-culture with morphologically good COCs (having three or more layers of cumulus cells) could improve the maturation and utilization rates of morphologically poor COCs. Our results revealed that the oocyte maturation rate, glutathione level, embryo development capacity, blastocyst quality, and cumulus cell gene expression levels of BCL-2 and PCNA were similar in the co-culture and good quality-groups, and that these levels were all significantly higher than those in the poor quality-group. Our results strongly suggest that the co-culture strategy greatly improved the utilization rate of morphologically poor COCs without reducing their capacity for maturation and subsequent development.

This study was performed to recognize species composition of Anopheline mosquitoes and infection rates of Plasmodium vivax in the northern part of South Korea. Adult mosquitoes were collected at 9 Republic of Korea (ROK) army installations in northern part of Geyonggi Province near the demilitarized zone (DMZ) using black light traps. Polymerase chain reaction (PCR) was used to identify collected Anopheline specimens and detect P. vivax from them. During June to August 2016, total 481 anopheline mosquitoes were collected and identified. Anopheles kleini was the most frequently collected (56.1%), and followed by An. pullus (16.6%), An. sinensis (16.2%), An. belenrae (7.5%) and An. lesteri (1.5%). 6 pools (4.0%) were positive for P. vivax among 150 pools. The minimum infection rates (MIR) was 1.24. Our ongoing study will provide a meaningful data for the effective malaria elimination strategy.

The study was conducted to determine proper seeding rate and nitrogen fertilizer level for the effective seed production of Winter Rye (Secale cereale L.) with randomized block design with three replicates by combining both seeding rates (3, 5, and 7 kg/10a) and different nitrogen fertilizer application levels (0, 3, 6, and 9 kg/10a) in northern area of Gyeongbuk province from Oct. 7, 2013 to Jun. 15, 2014. Emergence and overwintering rates were not influenced but lodging degree was influenced by seeding rate and nitrogen fertilizer level. High lodging were observed at the seeding rates and nitrogen fertilizer levels of more than 5 kg/10a and 6 kg/10a, respectively (p < 0.01). Lodging less than 20% were observed at the seeding rate of 3 kg/10a regardless of the increase of nitrogen fertilizer level, furthermore, no lodging was shown though seeding rate was increased up to 7 kg/10a under the condition without nitrogen fertilizer. No. of leaves per plant, plant height and culm length were increased as affected by the increase of nitrogen fertilizer level rather than the increase of seeding rate. Spike length was shortened as affected by the increase of seeding rate while it was lengthened by the increase of nitrogen fertilizer level with no interaction effect between the two factors. No. of stems and spikes per m2 were influenced by the increase of nitrogen fertilizer level rather than by seeding rate with no interaction effect between the two factors. Grain yield was significantly increased as influenced by the increases of seeding rate (A) and nitrogen fertilizer level (B) with interaction effect (A × B), which resulted in the highest grain yield (310 kg/10a) at the seeding rate of 5 kg/10a and the nitrogen fertilizer level of 3 kg/ 10a. In conclusion, the proper seeding rate and fertilizer application level would be 5 kg/10a and 3 kg/ 10a, respectively to effectively produce the winter rye seeds in northern Gyeongbuk province.

The aim of this study is to evaluate the effects of vitamin or mineral supplements on the conception rates of dairy heifers when replacing the last injection of GnRH with hCG in ovsynch protocol (experiment 1) and also to investigate whether the estrus synchronization treatment in the heifer stage affects the conception rates after 1st parturition (experiment 2). In experiment 1, 50 heifers were randomly assigned into 3 groups: 20 heifers each in groups 1 and 2, and 10 in group 3. All three groups were treated with an intramuscular injection of GnRH on day 0 (day 0 = the day of program start), PGF2α on day 7 and hCG on day 9, and were inseminated on day 10, 12~16h after hCG injection. In group 1 (vitamin group), the heifers were treated with an intramuscular injection of 5 ml of vitamin-ADE 500Ⓡ, and group 2 (mineral group) was treated twice with an intramuscular injection of 30 ml of mineral supplement-LAPTOVETⓇ on a one-week interval beginning on the day of hormone treatment (day 0 and day 7 respectively). Group 3 (control) was treated only with hormones. Pregnancy diagnosis was performed by ultrasonography through a rectal probe. First service conception rates (FSCR) and average services per conception (ASPC) were recorded for all subjects. Of the total 50 heifers, 6 (2 in group 1, 3 in group 2, and 1 in group 3) heifers were eliminated due to accidents during experiment 1. FSCRs were 58.8% (10/17), 66.7% (12/18) and 44.4% (4/9) in groups 1, 2 and 3, respectively. ASPCs were 1.53±0.72, 1.27±0.59 and 1.63±0.74 in groups 1, 2 and 3, respectively. Although there were no significant difference between the groups, relatively good results (higher FSCR and lower ASPC) were obtained in both group 1 and 2. In experiment 2, 11 primiparous cows from group 2 of experiment 1 in heifer stage which had been treated both with the hormones for estrus synchronizing and mineral supplements (ES group), and 12 primiparous cows treated only with minerals (non-ES group) were compared to examine the effects of estrus synchronization program on conception rates after 1st parturition. Following the examination, postpartum ASPCs were 1.55±0.82 and 2.17±1.47 in ES group and non-ES group, respectively. The postpartum average days open (ADO) were 116±56 and 197±93 in ES group and non-ES group, respectively. Although there were no significant difference between the two groups, desirable results (lower ASPC and shorter ADO) were found in ES group after 1st parturiton. In conclusion, experiment 1 indicates that vitamin or mineral supplement with ovsynch protocol may have some positive effect on FSCR and ASPC of dairy heifers, and in experiment 2, ES program in heifer stage had a positive effect on ASPC and ADO following 1st parturition.

Toxicity assessment of heavy metals (As, Cr and Pb) has been investigated by using the rate of survival and population growth(r) of marine rotifer, Brachionus plicatilis. The survival rate was determined after 24 hours of exposure to As, Cr and Pb. As and Cr reduced survival rate in dose-dependent manner and a significant reduction were occurred at concentration of greater than 30 and 150 mg L-1, but Pb had no effect on survival rate. The r was determined after 72 hours of exposure to As, Cr and Pb. As, Cr and Pb reduced r in dose-dependent manner and a significant reduction were occurred at concentration of greater than 5, 25 and 50 mg L-1. The toxicity of heavy metals were ranked As>Cr>Pb, with EC50 values of 12.98, 82.34 and 110.14 mg L-1, respectively. The no-observed-effect-concentration (NOEC) of r in As, Cr and Pb exposure were 1, 12.5 and 50 mg L-1, respectively. The lowest-observed-effect-concentration (LOEC) of r in As, Cr and Pb exposure were 5, 25, and 50 mg L-1, respectively. From the results, the concentration of As, Cr and Pb (greater than 5, 25 and 50 mg L-1, respectively) have toxic effect on the r of B. plicatilis in natural ecosystems. These results (including NOEC and EC50) might be useful for the mixing toxicity assessment and toxic guide line of heavy metals in marine ecosystems.

본 연구는 두 나라로 구성된 개방 경제를 가정한 DSGE 모형을 통해 환율과 거시경제변수간의 단절현상(exchange rate disconnect)에 대한 분석과 이론적 근거를 제시하고자 한다. 기존의 DSGE 모형에 금융중개기관(financial intermediation sector)을 추가하여 환율결정과정에서 의 은행의 역할을 강조하였다. 2007년 국제금융위기이후로 최근의 자산가격연구(asset pricing theory)의 중요한 흐름은 자산가격형성에 있어서 은행이 가지는 자금조달제약(financial constraint) 의 영향을 강조하는 것이다. 본 연구에서도 은행은 1. 자국의 가계로부터의 예금조달만 가능하며 (segmented global deposit market), 2. 예금조달은 순자산 규모에 제약을 받는다(balancesheet constraint)는 두 가지 자금조달제약을 가정하였다. 이 두 가지 제약으로 인해 국가 간 소 비의 차이가 환율과 연결되지 않는다는 것을 이론적으로 분석함으로써, 환율과 거시경제변수간의 단절현상 중 하나인 배커스-스미스 퍼즐(Backus-Smith puzzle)에 대한 하나의 근거를 제공하였 다. 모형을 미국과 캐나다의 주요 거시 경제 변수 moment 들에 맞춘 실증 분석 결과, 두 나라의 소비 차이와 환율의 상관계수는 -0.25로 나타나 일반적으로 두 변수간 음(-)의 상관계수를 보이는 배커스-스미스 퍼즐과 부합하였다.

1. 두 차례의 오일쇼크(1973년, 1979년)와 세계곡물위기 (2008년)는 상대적으로 천연자원이 풍부하지 못한 국가들에게 위협이 되었다. 우리나라의 경우, 식량의 약 70% 이상을 수입 에 의존하고 원유의 100%를 수입에 의존하기 때문에 식량 및 석유의 가격변동으로 인한 위험에 노출된 정도가 심하였다. 2. 하지만, 위험정도는 국가 간의 부존자원, 이를 대체할 수 있는 기술력 수준, 경제변동률 등에 따라 다르게 분석되었다. 3. 본 논문의 연구목적은 이러한 개별 국가가 처한 위험 정 도를 알아보기 위해, 2개 구간(1971-1990년, 1991-2011년)으로 나누어 국가 유형화를 시도함. 유형화를 위해 요인분석, 군집분 석을 실시하였으며 아래와 같은 몇 가지 시사점을 도출하였다. 4. 본 논문에서는 (1) 시간이 흐름에 따라 식량 자원보다 에 너지 자원의 활용이 많아져 경제변동률이 높은 유형에는 에너 지 자급률이 높은 국가들이 다수 포함되어 있음을 알 수 있고, (2) 국가별 식량 안보수준의 변화는 에너지 안보수준의 변화 에 비해 부정적인 방향으로 흘러가고 있다는 것을알 수 있으 며, (3) 생산력 수준이 낮은 국가들의 식량자급률은 하락하는 방향으로 이행되고 있는 것으로 나타났다. 이러한 분석결과는 식량자급률 하락에 따른 식량 자원 분포의 비대칭성 문제와 아울러식량 자원 생산에 있어서의 불균등도 심화 문제를 야기 시킬수 있다는 측면에서 시사하는 바가 크다.

본 연구는 잎새버섯 병 재배시 적합한 배지조성비율을 구명하고자 수행되었다. 배지조성은 참나무톱밥: 옥수수피: 건비지를 건물중량 비 율로 T1처리(67:11:22), T2처리(68:15:17), T3처리(74:14:12)의 3처리를 두고 시험한 결과, 발이율은 T1처리에서 72.6%, T2처리에서 72.1%로 두 처리 간 유의적 차이가 없었으나 T3처리에서는 65.8%로서 다른 두 처리에 비하여 낮았다. 이병률은 T2처리에서 4.1%, T3처리에서 3.7%인데 비하 여 T1처리에서는 9.8%로 가장 높았다. 수확률은 T1처리 에서 64.1%, T3처리에서 63.6%인데 비하여 T2처리에서 는 70.5%로 가장 높았다. 병당 자실체 중량은 T1처리에 서 85.5 g, T2처리에서 83.3 g으로 두 처리 간 유의적 차 이가 없었으나 T3처리에서는 72.4 g으로 다른 두 처리에 비하여 낮았다. 입병 수 10,000병 기준으로 재배 시 수량은 T2처리에서 587 kg으로 T1처리 및 T3처리에 비하여 각각 7% 및 28%가 높았다. 따라서 잎새버섯 병재배 시 적합한 배지조 성비율은 건조중량비율로 참나무톱밥: 옥수수피: 건비지 가 68:15:17인 것으로 나타났다.

애멸구(Laodelphax striatellus)는 rice stripe virus (RSV)의 매개충으로 벼에 큰 피해를 주는 해충이다. 본 연구에서는 애멸구의 장·단시형, 암·수, 약·성충에 대한 RSV 보독률과 이병률을 비교하였다. 애멸구의 장·단시형의 RSV 보독률은 각각 60.7%, 63.1%로 크게 차이는 없었다. 암·수에 대한 RSV 보독률은 각각 61.9%, 52.2%로 암컷의 보독률이 더 높았으나 유의성은 없었다. 약·성충의 보독률을 비교한 결과 각각 51.2%, 58.7%로 역시 크게 차이가 나지는 않았다. RSV에 감염된 애멸구에 노출된 건전한 벼의 이병률은 장시형은 53.3%, 단시형은 48.2%를 보였으며, 약·성충의 이병률은 각각 38.2%, 42.6%를 보여 유의성은 없었다. 반면 암컷은 50.5%의 이병률을 보이고 수컷은 22.3%의 이병률을 보여 암컷이 수컷에 비해 22.3% 이병률이 높아 유의성이 있었다. 또한 벼와 애멸구의 RSV 감염여부에 의한 애멸구의 발육기간은 건전한 벼에 RSV 감염 애멸구를 접종 했을 때 가장 긴 것으로 나타났으며, 건전한 벼에 건전한 애멸구를 접종 했을 때 발육기간이 가장 짧은 것으로 나타났다.