Bi0.5Na0.5TiO3 (BNT) based ceramics are considered potential lead-free alternatives for Pb(Zr,Ti)O3(PZT) based ceramics in various applications such as sensors, actuators and transducers. However, BNT-based ceramics have lower electromechanical performance as compared with PZT based ceramics. Therefore, in this work, lead-free bulk 0.99[(Bi0.5Na0.5)0.935Ba0.065](1-x)LaxTiO3-0.01SrZO3 (BNBTLax-SZ, with x = 0, 0.01, 0.02) ceramics were synthesized by a conventional solid state reaction The crystal structure, dielectric response, degree of diffuseness and electric-field-induced strain properties were investigated as a function of different La concentrations. All samples were crystallized into a single phase perovskite structure. The temperature dependent dielectric response of La-modified BNBT-SZ ceramics showed lower dielectric response and improved field-induced strain response. The field induced strain increased from 0.17% for pure BNBT-SZ to 0.38 % for 1 mol.% La-modified BNBT-SZ ceramics at an applied electric field of 6 kV/mm. These results show that Lamodified BNBT-SZ ceramic system is expected to be a new candidate material for lead-free electronic devices.

The anti-proliferative efficacy of t,t-conjugated linoleic acid (t,t-CLA), c9,t11-CLA, and t10,c12-CLA was compared in several human cancer cell lines. Gastric NCI-N87, liver Hep3B, pancreas Capan-2, and lung NCI-H522 cancer cells were incubated with 50 μM CLA isomers over a period of 6 days. The t,t-CLA inhibited the growth of all cancer cell lines to different extents, but c9,t11-CLA and t10,c12-CLA inhibited or stimulated the growth of the cancer cell lines. NCI-N87 cells were the most sensitive to growth inhibition and apoptosis from all CLA isomers tested. In NCI-N87 cells, CLA isomers reduced the release of arachidonic acid (AA) via the inhibition of cytosolic phospholipase A2 (cPLA2 ) activity, consequently reducing the production of PGE2 through the inhibition of cyclooxygenase-2 (COX-2). The efficacies of CLA isomers were in the following order (from most to least effective): t,t-CLA, t10,c12-CLA and c9,t11-CLA. Overall, these results imply that the anti-proliferative efficacy of t,t-CLA on cancer cells, especially NCI-N87 cells, was greater than other CLA isomers due to its induction of apoptosis through the inhibition of cPLA2 and COX-2 activities.

We previously reported Pear Pest Forecasting Management System (PPFMS) for the Improvement of pass ratio of Korean exporting pears. It is consisted of regular field forecasting by pear farmers, meteorological data obtained by automatic weather station (AWS), an internet web page (http://pearpest.jnu.ac.kr/) as information collecting and providing ground, and information providing service. Currently, we are expanding this system to the area, Cheonan and Ansung, where pear orchards are organized into exportation-specific group. Further, the information obtained from field forecasting and AWS were up-loaded to under-constructing upgraded webpage (http://www.kpear.kr), with several pest/disease-related information. We hope this pest forecasting management system increases the pass ratio of Korean exporting pears throughout establishment of farmer-oriented forecasting, inspiring farmers’ effort for the prevention and forecasting of diseases and pests occurring at pear orchards.

The pear psylla, Cacopsylla pyricola Foerster (Homoptera: Psyllidae), is a serious insect pest of commercial pear crops. The species, which resides on pear trees throughout its life cycle, is rapidly spreading in some regions of the world. Given the life cycle, it is unclear how such a rapid spread has been facilitated. Presently, the population genetic structure of the species including genetic diversity and gene flow was studied to understand the nature of dispersal and field ecology of the species. Pear psylla was collected from several pear orchards in Korea. The 658-bp region of mitochondrial COI gene and the 716-bp long complete internal transcribed spacer 2 (ITS2) of the nuclear ribosomal DNA were sequenced. Unlikely other previously studied insect pests, the COI-based genetic diversity of the pear psylla was extremely low (maximum sequence divergence of 0.15%). This finding allowed us to conclude that the species may have been introduced in Korea relatively recently, possibly with the phenomenon of genetic bottlenecks. ITS2 sequence-based analyses of phylogeny, population differentiation, gene flow, and hierarchical population structure all concordantly suggested that the pear psylla populations in Korea are neither genetically isolated nor hampered for gene flow. These genetic data are concordant with the dispersal of an overwintering winterform morph outside the non-pear habitat in the fall and the possibility of subsequently longer distant dispersal.

In the previous study, the plant essential oils such as clove bud , thyme white and garlic oils gave potent toxicity with the range of 1.5 to 4.5×10-3 ul cm-3 of LC50 values against Bemisia tabaci. Based on the bio-assay results, three plant essential oils(clove bud, thyme white and garlic) were applied to 30% emulsion type. The 100, 200 and 400 fold dilution of these emulsions was showed mild toxicity under port scale treatment against Q biotype. At each fold dilution, clove bud showed 44, 26 and 14%, and thyme white produced 44, 39 and 27%, respectively. Of garlic emulsion, its toxicity was evaluated with 27, 26 and 11%, respectively. But, in case of clove bud and thyme white mixture, their toxicity was more good under the mixture than under the single treatment. Mixture with clove bud 200 fold dilution adding to thyme white 200 fold dilution showed potent activity with 86% mortality. And also 200 adding to 400, and 400 to 400 exhibited 61%, 76%, respectively. These essential oil mixtures showed similar strong toxicity against B biotype under port scale test. In particular, the mixture with clove bud 200 fold dilution adding to thyme white 200 fold dilution showed the highest synergistic effect. Toxicity to plants, except the 100 fold dilution of these emulsions was not observed.

Recent studies on nuclear transfer and induced pluripotent stem cells have demonstrated that differentiated somatic cells can be returned to the undifferentiated state by reversing their developmental process. These epigenetically reprogrammed somatic cells may again be differentiated into various cell types, and used for cell replacement therapies through autologous transplantation to treat many degenerative diseases. To date, however, reprogramming of somatic cells into undifferentiated cells has been extremely inefficient. Hence, reliable markers to identify the event of reprogramming would assist effective selection of reprogrammed cells. In this study, a transgene construct encoding enhanced green fluorescent protein (EGFP) under the regulation of human Oct4 promoter was developed as a reporter for the reprogramming of somatic cells. Microinjection of the transgene construct into pronuclei of fertilized mouse eggs resulted in the emission of green fluorescence, suggesting that the undifferentiated cytoplasmic environment provided by fertilized eggs induces the expression of EGFP. Next, the transgene construct was introduced into human embryonic fibroblasts, and the nuclei from these cells were transferred into enucleated porcine oocytes. Along with their in vitro development, nuclear transfer embryos emitted green fluorescence, suggesting the reprogramming of donor nuclei in nuclear transfer embryos. The results of the present study demonstrate that expression of the transgene under the regulation of human Oct4 promoter coincides with epigenetic reprogramming, and may be used as a convenient marker that non-invasively reflects reprogramming of somatic cells.

다양한 재료특성(Si/Al 몰비, 두께, 구조적 불완전성)을 갖는 Na형 faujasite 제올라이트 분리층을 다공성 α-알루미나 튜브 표면에 수열조건에서 이차성장 시키고 CO2/N2 분리거동을 CO2/N2 몰비가 1인 혼합기체에 대하여 30℃에서 평가하였다. 수열조건 중에서 수열용액 내의 SiO2 양은 형성된 제올라이트 분리층의 재료특성에 가장 큰 영향을 주는 변수임을 확인하였다. 즉, 수열용액 내의 SiO2 양이 증가함에 따라서 형성된 제올라이트 분리층의 Si/Al 몰비, 두께, 구조적 불완전성(discontinuity)은 동시에 증가하였다. 본 논문에서는 불완전한 치밀화에 의해 잔존하는 결정립간 공극(void), GIS Na-P1 상에 의해 형성된 균열(crack) 등 구조적 불완전성이 CO2/N2 분리에 가장 큰 영향을 주는 재료특성이며, 투과부에서의 CO2 탈착이 전체 CO2 투과의 율속단계(rate-determining step)임을 확인하였다.

Embryonic germ (EG) cells are undifferentiated stem cells isolated from cultured primordial germ cells (PGC). These cells share many characteristics with embryonic stem cells including morphology and pluripotency. Undifferentiated porcine EG cell lines demonstrating capacities of differentiation both in vitro and in vivo have been established. Since EG cells can be cultured indefinitely in an undifferentiated state, whereas somatic cells in primary culture are often unstable and have limited lifespan, EG cells may provide inexhaustible source of karyoplasts in nuclear transfer (NT). In this study the efficiencies of NT using porcine EG and fetal fibroblast cells were compared. Two different techniques were used to perform NT. With conventional NT procedure (Roslin method) involving fusion of donor cells with enucleated oocytes, the rates of development to the blastocyst stage in EG and somatic cell NT were 16.8% (59/351) and 14.5% (98/677), respectively. In piezo-driven microinjection (Honolulu method) of donor nuclei into enucleated oocytes, the rates of blastocyst formation in EG and somatic cell NT were 11.9% (15/126) and 9.4% (9/96), respectively. Regardless of NT methods used in this study, EG cell NT gave rise to comparable rate of blastocyst development to somatic cell NT. Overall, EG cells can be used as karyoplast donor in NT procedure, and embryos can be produced by EG cell NT that may be used as an alternative to conventional somatic cell NT.