The feeding habits of the Pacific bluefin tuna, Thunnus orientalis were examined based on the stomach contents of 330 specimens caught by offshore large purse seine fishery in the southern sea of Korea, 2011. The size of Pacific bluefin tuna used in this study ranged from 34.1 to 67.3 cm in fork length (FL). The percentage of empty stomachs was 41.8%. The main prey items were Pisces and Cephalopoda based on percentage IRI (index of relative importance). The main fish preys were Trachurus japonicus, Bregmaceros japonicus, Engraulis japonicus, and Cephalopoda were Todarodes pacificus, Loligo edulis, Watasenia scintillans. T. orientalis showed ontogenetic change in diet composition. Although Pisces dominated the diet of all length classes the portion of Cephalopoda was relatively higher in size between 40 and 50 cm other than length classes. In terms of seasonal variation in feeding habits, Pisces was the main prey group in all seasons, but Cephalopoda was also frequently consumed during spring and autumn based on %IRI.

The objective of this study was to identify the phenotypic relationships among calving difficulty, calf birth weight and gestation length of Holstein dairy cattle under the environment of Korea. A total of 1,834 calving records collected by Dairy Science Division of National Institute of Animal Science, RDA from 2000 to 2014 was analyzed. General linear multivariate models for calving difficulty scores (CD: 1=no assistance, 2=minor assistance, 3=two to three persons assisted, 4=more than three persons assisted, 5=cesarean section), calf body weight at birth (BW), and gestation length (GL) included fixed effects of year and season (spring, summer, autumn, winter) of births (YS), sex of calves, and parity. For GL and BW, all three fixed effects (YS, sex of calves, parity) were significant (p<0.05). For CD, the effects of YS and sex of calves were significant (p<0.05). Bull calves were born with heavier BW by 3.18 kg, with greater CD by 0.18 point and with longer GL by 0.6 days than heifer calves. The least squares mean of BW was the heaviest at the third parity (44.1 kg) compared to those at the first, the second and the fourth parities or later (41.3-41.9 kg). The least squares mean CD at the first parity was 1.74 point, which was higher than CD at the second and later parities (about 1.68 points). Phenotypic correlation (partial residual correlation) between GL and BW was 0.36. But those between GL and CD and between BW and CD were -0.03 and 0.04, almost zeros. To conclude, we observed higher incidence of calving difficulty in the first calving than in the later ones. Further investigation on the relationships between calf’s birth weight and calving difficulty is needed

Quaternary amonium salts are used as anion-exchange and also easily decomposed due to their intrinsic structural instability. These drawbacks have limited the long-term utilization of the membranes. The objectives of this study are to synthesize high performance anion-exchange membranes and to investigate their electrochemical properties The new membranes were prepared via a monomer sorption method. Their morphological and electrochemical properties have been investigated through various analyses. While the accumulated water-splitting flux of the commercial membrane containing conventional quaternary ammonium groups was shown to largely increase with time, theirs of the new membrane was shown without significant change.

In this study, growth and yield characteristics of 14 potato varieties were analyzed in the uncultivated field Saemangeum reclaimed tidal land in spring season cropping and to select suitable varieties for the cultivation. The shoot emergence has been started about 20 days after planting and has been continued for 10 ~ 22 days after first emergence. All varieties showed 90% or higher emergence rate. The potato varieties yield was classified into three groups depend on the total yield. High yield varieties; Atlantic, Chuyeong, Seohong, Chubaek and medium yield varieties; Chudong, Goun, Haryung, Jopung, Dejima, Superior and low yield varieties; Hongyoung, Jayoung, Jowon, Namseo. For the marketable yield, Jowon, Altantic, Chuyeong, Jopung, Seohong, Goun, Superior and Haryung varieties showed 70% or higher while Hongyoung showed the lowest with 47%. According to the results of virus detection test after two year successive cultivation in reclaimed tidal land, very low amount of Potato virus Y (PVY) was detected only on Seohong sprouts (fitst year) and Dejima leaves (second year) while other varieties were shown no symptom of virus. From the survey with consumers, Haryung, Superior, Goun, Dejima and Chuyeong varieties were found to be relatively higher in the purchase preference for the shape, color and taste. The measurement of antioxidant activity showed Jayoung variety to be excellent with the total phenol contents and DPPH antioxidant activity. Atlantic, Chuyeong, Seohong, Goun, Haryung and Jopung varieties showing high total yield and marketability of 70% higher were considered to be suitable for cultivation in the sandy loam of Saemangeum reclaimed tidal land. According to the above results, the growing possibility of spring potatoes in he sandy loam of newly Saemangeum reclaimed tidal land.

Pacific herring Clupea pallasii eggs were attached to the gill net in Korean coastal waters off Busan. To conservation and management the eggs attached to the gill net, we followed the natural hatching in coastal waters from five days after fertilization to the hatching finished, where the temperature was 9°C. The diameter of fertilized eggs was 1.24–1.55 mm (n= 50), and had a segmented pale yellow yolk, no oil globule. Natural hatching had started by 10 days after fertilization. Mass hatching occurred around 11–12 days after fertilization, most of eggs separated from the gill net. Therefore, when the Pacific herring eggs attached in gill net, should be natural hatching–induced in coastal waters during 12–14 days.

Ti alloys are extensively used in high-technology application because of their strength, oxidation resistance at high temperature. However, Ti alloys tend to be classified very difficult to cut material. In this paper, The powder synthesis, spark plasma sintering (SPS), bulk material properties such as electrical conductivity and thermal conductivity are systematically examined on Ti2AlN and Ti2AlC materials having most light-weight and oxidation resistance among the MAX phases. The bulk samples mainly consisted of Ti2AlN and Ti2AlC materials with density close to theoretical value were synthesized by a SPS method. Machining characteristics such as machining time, surface quality are analyzed with measurement of voltage and current waveform according to machining condition of micro-electrical discharge machining with micro-channel shape.

경포호에서 수질 변수들의 장기적인 경향을 파악하기 위하여 1998년부터 2013년까지 매년 3월부터 11월까지 2개월에 1회씩 3개 지점에서 조사된 15가지 수질변수들과 강우량자료를 이용하였으며, Mann-Kendall test, Sen’s slope estimator 및 linear regression을 적용 분석하였다. 계절 변화 분석에는 Mann-Kendall test 및 Sen’s slope estimator만 이용하였다. 분석결과 염분, 투명도 및 영양염류 (총인, 용존무기인, 총질소, 질산성 질소, 암모니아성 질소)의 변수들만 통계학적으로 유의적인 경향을 보였다. 선형회귀 분석에서는 염분 (표층과 심층의 전 지점)과 투명도 (지점 1)만이 통계학적으로 유의적인 증가 경향을 나타냈으나, 비모수법에 의한 분석에서는 염분과 투명도 모두 전 지점에서 통계학적으로 유의적인 증가 경향을 보였다. 통계학적으로 유의적인 감소 경향을 보인 수질변수들은 선형회귀 분석에서는 용존산소 (표층 지점 1, 심층 지점 2와 3), 총인(지점 1과 2), 용존무기인, 총질소, 질산성 질소 및 암모니아성 질소, 비모수법에 의한 분석에서는 용존산소 (심층 전 지점), 총인, 용존무기인, 총질소, 질산성 질소 및 암모니아성 질소였다. 계절적인 경향을 분석한 결과 봄에는 염분, 탁도, 투명도 및 부유물질 (SS), 여름에는 염분, 투명도, 질산성 질소 및 부유물질, 가을에는 수온, 염분, 투명도 및 부유물질 만이 증가하는 경향을 보였으며 이들 변수들이 계절에 따라 다소 차이를 보이는 것으로 나타났다. 특히 봄과 여름에 비해서 가을철에 Mann-Kendall test 및 Sen’s Slope estimator에 의해 유의적인 경향을 나타낸 수질변수들이 많았다. 가장 강한 증가 경향을 보인 것은 염분이었으며 봄보다는 여름과 가을에 뚜렷하였다. 투명도도 염분과 유사한 특성을 보였다. 강우량은 조사기간 동안 전체적으로 감소하는 경향을 보였다. 경포호에서 영양염류의 유의적인 감소경향은 그동안 강릉시에서 추진해온 석호 복원사업 및 해수유통 (수중 보 철거) 등과 관련이 있는 것으로 판단되나 정확한 원인 규명을 위해서는 보다 면밀한 조사가 수반되어야 할 것으로 사료된다.

소나무재선충병의 확산은 매개충 분포에 의하여 좌우되는데, 지금까지 매개충별 분포지역은 북방수염하늘소(Monochamus saltuarius)는 중부지방, 솔수염하늘소(M. alternatus)는 남부지역으로 알려져 있다. 현행 방제는 매개충 우화기(4~8월)를 피해 9월에 시작하여 이듬해 4월 말까지 방제를 완료하도록 되어 있으며, 매개충 활동시기 동안은 매개충 종류별 분포지역에 따라서 약제 살포시기를 달리하여 지상 및 항공방제를 실시하고 있다. 매개충의 종류별 분포지역 및 활동시기에 따른 방제 적기에 방제가 실행되어야 방제의 효율성을 높일 수 있기에 전국 11개소에 설치한 우화상으로부터 매개충의 우화상황을 조사하고, 매개충 페로몬 유인트랩을 이용하여 매개충의 임내 활동시기를 조사하였다. 그 결과, 북방수염하늘소의 분포지역이 남부지역(밀양, 합천)까지 확대되었고 혼생지역의 범위 또한 넓어졌다. 기존 매개충의 우화ㆍ활동시기가 북방수염하늘소는 4~7월까지, 솔수염하늘소는 5~8월까지로 보고되었으나, 최근 북방수염하늘소는 8월까지, 솔수염하늘소는 10월까지 임내에서 활동하는 것이 확인되었다. 따라서, 매개충 분포 및 지역별 우화ㆍ활동시기에 따른 지역별 맞춤형 예찰ㆍ방제시기를 확정하여 방제적기에 따른 방제 방법 이행으로 방제효율성을 제고하고자 한다.

Three specimens of larvae (5.2~7.8 mm in standard length (SL)), of the family Scombridae, were collected from the southeastern waters off Jeju Island in August, 2014. These specimens were identified to Katsuwonus pelamis have melanophores distributed on the 1st dorsal-fin spines and post ventral margin on caudal peduncle. An analysis of the cytochrome oxidase submit I (COI) sequences (652 base pairs) of mitochondrial DNA showed that our specimens must be K. pelamis, because their sequences were concordant with those of the adult K. pelamis (genetic distance= 0.000~0.002), followed by Auxis rochei (genetic distance= 0.061~0.063) and Euthynnus affinis (genetic distance= 0.077~0.079). During the larval stage, K. pelamis differed from Thunnus spp. species in melanophores distribution period of 1st dorsal-fin spines, lower jaws and ventral margin on caudal peduncle. In conclusion, occurrence of K. pelamis larvae means Korean waters are potential spawning ground of K. pelamis.

Fe2O3 coated plate mica(Fe2O3/mica) for infrared reflectance red pigment was prepared under hydrothermal treatment. Fe2O3 was perfectly coated on mica via the difference of surface charge between Fe2O3 and mica particles at pH 3. Fe2O3/mica was then calcined at 800 oC to stabilize the coated layer on mica. The infrare (IR) reflectance pigments were characterized by X-ray diffraction, FE-SEM, zeta potential, and a UV-Vis-NIR spectrophotometer. In particular, the CIE color coordinate and IR reflectance properties of Fe2O3/mica pigments were investigated in relation to the thickness variation of the Fe2O3 layer coated on mica of various lateral sizes. The isolation-heat red paints containing the pigments were prepared and optimized with a thinner, settling agent, and dispersant. Then, the films were made. The thermal property of isolation-heat on these films was observed through the relationship of the IR reflectance value, which was based on the variation of the Fe2O3 layer’s thickness coated on mica and mica’s lateral size as IR reflectance pigment. With an increase in IR reflectance on these films, the thermal property of isolation-heat was effectively enhanced.

Mirizzi’s syndrome (MS) caused by the retention of a stone in the cystic duct stump after cholecystectomy is rare. Most cases of MS are treated by surgical intervention. However, developments of endoscopic accessories and techniques have resulted in the recent introduction of endoscopic treatments for MS. Furthermore, in view of the postoperative morbidity caused by post-operative scarring, the endoscopic approach should be preferred to the surgical approach. In the described case, the authors were able to remove a remnant cystic duct stone endoscopically because the cystic duct stump was wide and non-tortuous. This case shows endoscopic retrograde cholangiopancreatography with mechanical lithotripsy can be utilized in suitable cases of type I MS development after cholecystectomy.

본 연구는 옥수수 사일리지를 이용하여 TMR 제조 시 배합시간에 따른 물리적 특성(Particle size, peNDF 및 laceration)의 변화를 조사하고, 반추위 내 in situ 건물분해율 및 비유중기 착유우의 유생산성에 미치는 영향을 조사하고자 수행되었다. TMR 시험사료는 동일한 원료를 이용하여 배합시간을 30분(T1구)과 50분(T2구)으로 제조하였다. Penn State Particle Size Separator (PSPS, 19 mm와 8mm 체)로 분리하여 입자크기의 분포를 분석한 결과 배합 시간이 30분(T1)에서 50분(T2)로 증가함에 따라 하층(<8mm)의 비율이 유의적으로 증가하였고(p<0.01), peNDF>8.0는 유의적으로 감소하였으며(p<0.01), 굵은 비율(≥1mm) 이 유의적으로 감소하였다(p<0.01). 반추위 내 in situ 건물 분해율은 모든 배양시간에서 처리구간 차이가 없었지만 24시간 배양에서 T1구에서 유의적으로 높게 나타났다. (p<0.01). 산유량은 처리구간 차이가 없었지만 유지방은 T1이 유의적으로 높게 나타났다(p<0.01). 본 연구 결과에서 옥수수 사일리지 위주의 TMR 제조 시 배합시간을 단축 조절함으로서 산유량 및 유성분에 대한 부정적 영향 없이 조사료의 물리적 사료가치를 증진하는데 효과가 있을 것으로 기대된다.

배추좀나방(Plutella xylostella)이 국내에서 월동이 가능한 지 명확하지 않았다. 본 연구는 배추좀나방의 내한성에 기초한 야외 노출 실험 을 실시하여 월동 환경 조건을 결정하고, 동계 야외 지역의 배추좀나방 유충 서식지 관찰 및 성페로몬을 이용한 성충 모니터링을 통해 월동이 가 능한 지 조사하였다. 또한 이들 월동집단의 유래를 추적하기 위해 다형유전좌위를 이용한 집단 분석을 실시하였다. 배추좀나방의 체내빙결점 보 다 높은 -5℃로 처리한 결과 모든 미성숙 발육태에서 뚜렷한 생존력 저하를 보여 직접적 냉해 피해를 주었다. 여기서 유충발육태는 가장 낮은 냉 해 피해를 받았다. 그러나 5℃로 장기간(4 주) 처리한 결과 냉해 피해는 없었지만, 유충의 경우 먹이가 없는 상태에서 치사율이 증가했다. 모든 발 육태의 배추좀나방을 대상으로 겨울 기간 동안 야외조건에 노출시킨 결과 모든 발육태에서 생존력 저하를 나타냈다. 그러나 비가온 실내조건에서 저온 피해를 줄였으며 유충의 경우 먹이가 공급되면 생존력이 뚜렷하게 증가하였다. 동계 성페로몬 모니터링 결과 2014년도 최초의 성충발생일 은 유사한 시기에 서로 다른 지역(약 260 Km 거리)에서 나타났으며 월동집단의 성충은 4월 상순까지 포획되었다. 지역간 이들 월동집단의 유전 적 거리는 다형분자마커를 이용하여 분석되었으며 이들 월동집단들 사이에 뚜렷한 유전적 분화가 있는 것을 나타냈다. 본 연구는 배추좀나방의 국내 월동이 남쪽 지역 또는 기주 식물이 있는 시설재배지에서 가능한 것으로 제시하고 있다.