농촌진흥청 개발 품종인 토종벌 신품종(질병저항성 우수계통)에 대해 전남지역에서의 형질특성(봉세발달, 마리당 수밀력, 청소력 등)을 조사하였다. 질병저항성 계통(RS)으로 육성된 토종벌의 유밀기 마리당 수밀력은 들어오는 일벌의 무게가 80.89±8.95mg, 나가는 일벌의 무게가 63.56±8.90mg으로 조사되었고, 비저항성계통(NRS)은 각각 83.22±1.39, 66.67±1.20mg으로 조사되어 RS에서 그 무게차가 0.7mg 더 높았으나 통계적 유의차는 없었다. Pin killed test에 의한 사충제거능력(청소력)은 제거하지 못한 유충잔존율이 RS에서 12시간과 24시간 경과시 14.00±10.39와 7.00±3.46으로, NRS에서는 20.33±14.29, 13.33±10.41%로 조사되었으며, 특히 RS와 NRS의 사충 비제거율이 24시간 경과하였을 때 4.67±2.08, 8.33±7.77%로 RS가 우수한 특성을 보였다. 신규여왕벌 입식 후 봉군세력발달은 NRS에 비하여 RS의 일벌수, 번데기 및 유충수의 발달율이 안정적이고 다소 빠르게 증가하였다.

기후변화, 외래병해충발생, 밀원수 감소 등 여러 요인으로 인해 우리 나라의 양봉농가는 벌꿀생산량 및 농가소득이 감소하는 추세이다. 또한 밀원이 없는 시기에 가축용 사료가 아닌 고가의 식용설탕을 꿀벌의 인공사료로 급여하고 있어 농가는 ‘생산비 상승’과 ‘밀원수 부족’을 국내양봉업이 직면한 가장 큰 문제점으로 지적하고 있다. 이에 따른 양봉농가의 생산비를 절감하고 꿀벌의 생리·생태의 개선효과를 가지는 저가형 당액사료개발을 위해 농산부산물에서 추출한 천연당을 봉군에 적용시험을 추진하였다. 양파(OS-1, OS-2), 양배추(CS-1, CS-2), 바나나(Banana)부산물에서 추출한 천연당의 봉군당 평균먹이소모량(mL)은 설탕당액(대조구) 처리구와 비교시 바나나추출당액 급여구에서 5500.00±0.00, 5133.33±404.15로 유사하였다. 그러나 꿀벌의 봉세발달은 대조구에 비해 21006.7±2137, 17403.3±2257마리로 조사되어 낮은 경향을 나타내었고 수명조사 결과는 큰 차이가 없었다. 농산부산물을 이용한 천연당은 우선 꿀벌의 기호도 향상을 우선으로 개선시켜야 할 것으로 보인다.

We demonstrated an effective way of preparing melt spinnable mesophase pitches via catalytic hydrogenation of petroleum residue (fluidized catalytic cracking-decant oil) and their subsequent thermal soaking. The mesophase pitches thus obtained were analyzed in terms of their viscosity, elemental composition, solubility, molecular weight, softening point and optical texture. We found that zeolite-induced catalytic hydrogenation under high hydrogen pressure contributed to a large variation in the properties of the pitches. As the hydrogen pressure increased, the C/H ratio decreased, and the solubility in n-hexane increased. The mesophase pitch with entirely anisotropic domains of flow texture exhibited good meltspinnability. The mesophase carbon fibers obtained from the catalytically hydrogenated petroleum residue showed moderate mechanical properties.

Despite that porcine spermatogonial stem cells (pSSCs) have been regarded as a practical tool for preserving eternally genetic backgrounds derived from pigs with high performance in the economic traits or phenotypes of specific human diseases, there were no reports about precise definition of niche conditions promoting proliferation and maintenance of pSSCs. Accordingly, we tried to determine niche conditions supporting proliferation and maintenance of undifferentiated pSSCs for short-term. For these, undifferentiated pSSCs were progressively cultured in different composition of culture medium, seeding density of pSSCs, type of feeder cells and concentration of growth factors, and then total number of and alkaline phosphatase (AP) activity of pSSCs were investigated at post-6 day culture. As the results, the culture of 4x105 pSSCs on mitotically in activated 2x105 STO cells in the mouse embryonic stem cell culture medium (mESCCM) supplemented with 30 ng/ml glial cell line-derived neurotrophic factor (GDNF) was identified as the best niche condition supporting effectively the short-term maintenance of undifferentiated pSSCs. Moreover, the optimized short-term culture system will be a basis for developing long-term culture system of pSSCs in the following researches.

Poly(vinylidene chloride) (PVDC)-derived nanoporous carbons were prepared by various activation methods: heat-treatment under an inert atmosphere, steam activation, and potassium hydroxide (KOH) activation at 873, 1073, and 1273 K. The pore structures of PVDC-derived nanoporous carbons were characterized by the N2 adsorption technique at 77 K. Heat treatment in an inert atmosphere increased the specific surface area and micropore volume with elevating temperature, while the average micropore width near 0.65 nm was not significantly changed, reflecting the characteristic pore structure of ultramicroporous carbon. Steam activation for PVDC at 873 and 1073 K also yielded ultramicroporosity. On the other hand, the steam activated sample at 1273 K had a wider average micropore width of 1.48 nm, correlating with a supermicropore. The KOH activation increased the micropore volume with elevating temperature, which is accompanied by enlargement of the average micropore width from 0.67 to 1.12 nm. The average pore widths of KOH-activated samples were strongly governed by the activation temperature. We expect that these approaches can be utilized to simply control the porosity of PVDC-derived nanoporous carbons.

전기탈이온 장치를 통한 니켈이온의 이동메커니즘이 이온교환섬유의 전기화학적 특성을 이용하여 조사되었다. 포러스 플러그 모델과 확장된 넌스트-플라크 식이 니켈이온의 이동 현상의 해석을 위해서 적용되었다. 적용된 모델을 통해 전기탈이온 시스템의 성능증가는 이온교환섬유를 통해 변화되는 이동도에 기인하는 것이 아니라, 이온교환매개체의 자체 전도도에 의해 일어나는 전류 유발 효과에 의한 것으로 나타났다. 또한, 최적의 전기탈이온 공정운전이 최소화된 전기적 재생영역하에서 일어남을 본 연구를 통해 제시되었다.

전기투석 공정에서 이온교환막 표면에 형성되는 스케일 영향을 조사하기 위해 장기간 동안 운전되었다. 탈염공정 동안, Ca2+과 SO42- 이온의 농도는 농축실에서 연속적으로 증가하였으며 양이온교환막(Neosepta CMX)표면에 침전이 발생하였다. 초기 스케일 형성동안, 공정성능과 막 특성의 변화는 농축실 염농도 증가에 기인하여 일어나는 양이온교환막의 하계전류밀도가 감소하는 것을 제외하곤 미미하였다. 공정운전이 진행됨에 따라 양이온교환막의 한계전류밀도는 물의 해리 현상이 진행되어 300;A/m2까지 감소하였다. 막 오염은 농축실에서 양이온교환막 표면에 형성된 스케일과 물의 해리현상에 의해 유발된다는 결론을 얻었으며, 이러한 스케일 형성은 CaSO4의 용해도에 의해 예측 가능한 것을 알 수 있었다.

Background : Liriope platyphylla Wang et. Tang belongs to the Liliaceae and herbal medicinal plants. It is usually grown as ground cover plants. But the farm is cultivated medicinal plants in order to harvest its tuberous root. The cultivated area is 95ha and the production is 588 ton(2014). Miryang and Cheongyang are the main producing areas. This experiment was carried out to select a cultivar that are well adapted in middle regions in Korea. Methods and Results : It were investigated the tuber characteristics in four cultivars of Liriope platyphylla Wang et. Tang. The ratios of roots and tubers a plant was ranged 18.6 - 21.6%. Maekmundong 1 have more in tubers per a plant but lower in the rate of marketable tubers and 100-tubers weight than other 3 cultivars. Cheongshim was heavier and larger in tuberous root than 3 other cultivars. The tuber’s distributions in less than 10 ㎝ soil depth at the surface was 48.6% in Cheongshim, 58.4% in Seungsu 50.6% in Maekmundong 1 and 58.1% in Cheongyang native’s line. So, Seungsu and Cheongyang native’s line are believed to be suitable for harvesting by machines. The tuber’s yield was highest in Seungsu and was 5% higher than Cheongyang native’s line. The spicatoside A extracted with 80% MeOH was analyzed by 0.01 – 1.83 ㎎/g and Maekmundong 1 have been contained much more than other cultivars. Conclusion : Considering the yield and medicinal ingredients, Maekmundong 1 have good quality than Cheongshim, Seungsu and Cheongyang natives’s lines in middle regions in Korea.

The sex ratio (F:M) in the same population of oyster, Crassostrea gigas at the commencement of the study (2007) was 1:1.0, but changed to 1:2.8 by the end of the study (2008). The sex reversal rate in two-year-old oysters was 40.2%. Specifically, female to male sex reversal rate was 66.1%, which is higher than the male to female sex reversal rate of 21.1%. The sex reversal pattern of C. gigas appears to go from male female male, and as such is determined to be rhythmical hermaphroditism.

Manganese () is a trace element that is essential for normal physiology, and is predominantly obtained from food. Several lines of evidence, however, demonstrated that overexposure to exerts serious neurotoxicity, immunotoxicity and developmental toxicity, particularly in male. The present study aimed to evaluate the effect of 0, 1.0, 3.3, and 10 mg/kg/day doses of on the reproductive organs in the immature female rats. Rats (PND 22; S.D. strain) were exposed to () dissolved in drinking water for 2 weeks. The animals were sacrificed on PND 35, then the tissues were immediately removed and weighed. Histological studies were performed using the uteri tissue samples. Serum LH and FSH levels were measured with the specific ELISA kits. Body weights of the experimental group animals were not significantly different from those of control group animals. However, ovarian tissue weights in 1 mg and 3.3 mg dose groups were significantly lower than those of control animals (p<0.05 and p<0.01, respectively). Uterine tissue weights of 3.3 mg dose groups were significantly lower than those of control animals (p<0.01), while the 1 mg dose and 10 mg dose failed to induce any change in uterine weight. Similarly, only 3.3 mg dose could induce the significant decrease in the oviduct weight compared to the control group (p<0.05). Non-reproductive tissues such as adrenal and kidney failed to respond to all doses of exposure. The uterine histology revealed that the exposure could affect the myometrial cell proliferation particularly in 3.3 mg dose and 10mg dose group. Serum FSH levels were significantly decreased in 1mg dose and 10 mg groups (p<0.05 and p<0.01, respectively). In contrast, treatment with 1 mg dose induced a significant increment of serum LH level (p<0.05). The present study demonstrated that exposure is capable of inducing abnormal development of reproductive tissues, at least to some extent, and altered gonadotropin secretions in immature female rats. Combined with the well-defined actions of this metal on GnRH and prolactin secretion, one can suggest the might be a potential environmental mediator which is involved in the female pubertal process.

Muscle strength and endurance activities of Korean ginseng (Panax ginseng C. A. Meyer; KG) were compared with those of wild simulated cultivation ginseng (WCG) in mice. Fifty male ICR mice were divided into five groups: A (vehicle); B (WCG 100 mg/kg); C (WCG 500 mg/kg); D (KG 100 mg/kg); E (KG 500 mg/kg). Subsequently, the mice were subjected to the forced swimming test (FST) and treadmill test at the 4th and 7th weeks. The glycogen content in the muscle and blood analysis (levels of glucose, triglyceride (TG), IGF-1) were also performed immediately after the last FST and treadmill test at the 7th week. Immobility times in FST were shorter in WCG- than KG-treated groups, and the results of the treadmill tests were also significant except for KG-treated at 100 mg/kg. The glycogen content was increased in both groups with a peak at 500 mg/kg of WCG groups. Serum concentrations of TG and glucose were decreased by administration of KG and WCG and all treated groups showed increase in the level of IGF-1 in serum. These results suggest that KG and WCG supplementations are effective in escalating the muscle strength and endurance.