본 논문은 1979년과 2006년 사이 전세계 강수의 연평균 및 계절성의 시계열적 변화 양상을 색채를 체계적으로 사용하여 공간상에 가시화하는 방법론을 제시한다. 시계열 푸리에분석을 이용하여 분해된 중간 결과물에 로버스트 및 비모수 시계열 회귀분석을 적용하여, 세계 전반적으로 강수량의 연평균 및 계절성이 어떻게 변화하는지를 GIS/RS 프로그램인 이디리시를 사용하여 지도화한다. 본 논문에서 제시한 지도학적 방법론은 세계 강수 변화의 시공간적 역동성을 하나의 지도상에 함축적으로 표현할 수 있으며, 각 지역에서 관찰되는 각기 다른 변화 양상을 2차원 색채 범례를 통해 명확히 구분한다. 또한, 이 방법론은 기후변화와 관련된 연구 외에도 다른 래스터기반 시공간 자료 표현을 하는데 있어서도 유용하게 활용될 것이다.
The distribution patterns of estuarine copepods were investigated in the Seomjin River estuary of southern Korea after heavy rains in August 2006. Tidal influence extended 16 km from the estuary mouth. Each estuary zone (Oligohaline salinity< 5, mesohaline salinity 5~18, polyhaline salinity >18) changed within a range of about 5~6 km between low and high tides. A total of ten species were recorded, of which Pseudodiaptomus koreanus, Sinocalanus tenellus, and Tortanus dextrilobatus were predominant in the oligohaline zone; Acartia ohtsukai and Acartia forticrusa in the mesohaline zone; and A. erythraea, Calanus sinicus, Centropages dorsispinatus, Labidocera rotunda and Paracalanus parvus s. l. in the polyhaline zone. Their density was fastly reduced in the other zones. In particular, the oligohaline species migrated and aggregated into deeper water during ebb tides in order to retain their populations, while the same tendency was weaker for polyhaline species, suggesting that evolutionary traits primarily control population retention behaviors in estuarine environments.
The objective of this study was to determine the effect of post-activation treatment with cytoskeletal regulators in combination with or without 6-dimethylaminopurine (DMAP) on embryonic development of pig oocytes after parthenogenesis (PA) and somatic cell nuclear transfer (SCNT). PA and SCNT oocytes were produced by using in vitromatured pig oocytes and treated for 4 h after electric activation with 0.5 μM latrunculin A (LA), 10.4 μM cytochalasins B (CB), and 4.9 μM cytochalasins D (CD) together with none or 2 mM DMAP. Post-activation treatment of PA oocytes with LA, CB, and CD did not alter embryo cleavage (85.8~88.6%), blastocyst formation (30.7~ 32.4%), and mean cell number of blastocysts (33.5~33.8 cells/blastocyst). When PA oocytes were treated with LA, CB, and CD in combination with DMAP, blastocyst formation was significantly (P<0.05) improved by CB+DMAP (42.5%) compared to LA+DMAP (28.0%) and CD+DMAP (25.1%), but no significant differences were found in embryo cleavage (77.5~78.0%) and mean blastocyst cell number (33.6~35.0 cells) among the three groups. In SCNT, blastocyst formation was significantly (P<0.05) increased by post-activation treatment with LA+DMAP (32.9%) and CD+DMAP (35.0%) compared to CB+DMAP (22.0%) while embryo cleavage (85.5~85.7%) and blastocyst cell number (41.1~43.8 cells) were not influenced. All three treatments (LA, CB, and CD with DMAP) effectively inhibited pseudo-polar body extrusion in SCNT oocytes. The proportions of oocytes showing single pronucleus formation were 89.6%, 83.9%, and 93.3%, respectively with the increased tendency (P<0.1) by LA+DMAP and CD+ DMAP compared to CB+DMAP. Our results demonstrate that post-activation treatment with LA or CD in combination with DMAP improves pre-implantation development of SCNT embryos and the stimulating effect of cytoskeletal modifiers on embryonic development is differentially shown depending on the origin (PA or SCNT) of embryos in pigs.
The objective of this study was to examine the effect of in vitro maturation (IVM) medium, cytochalasin B (CB) treatment during intracytoplasmic sperm injection (ICSI), and electric activation on in vitro development ICSI-derived embryos in pigs. Immature pig oocytes were matured in vitro in medium 199 (M199) or porcine zygote medium (PZM)-3 that were supplemented with porcine follicular fluid, cysteine, pyruvate, EGF, insulin, and hormones for the first 22 h and then further cultured in hormone-free medium for an additional 21~22 h. ICSI embryos were produced by injecting single sperm directly into the cytoplasm of IVM oocytes. The oocytes matured in PZM-3 with 61.6 mM NaCl (low-NaCl PZM-3) tended to decrease (0.05<P<0.1) nuclear maturation when compared with oocytes matured in M199 (76.9% vs. 83.8%) but no significant differences were found in embryo cleavage, blastocyst formation, and mean number of cells in blastocyst (73.8% vs. 74.6%, 11.1% vs. 12.1%, and 28.4 cells vs. 30.1 cells, respectively). The oocyte degeneration was not reduced by CB treatment during ICSI (11.9%) when compared with no treatment control (11.3%) while the treatment showed detrimental effects (P<0.05) on embryonic cleavage (40.0%) and blastocyst formation (1.8%) rates when compared with control (60.0% and 11.5%, respectively). For activation of ICSI oocytes, additional electric stimulus has no positive or negative effect on in vitro development of preimplantation stage ICSI porcine embryos. Our results demonstrate that CB treatment during ICSI inhibits embryonic development of ICSI oocytes and additional electric activation after ICSI has no effect in improving ICSI embryonic development in pigs. Further studies are needed to improve ICSI efficiency by investigating factors influencing embryonic development after ICSI in pigs.
We present the relation between the genus in cosmology and the Betti numbers for excursion sets of three- and two-dimensional smooth Gaussian random fields, and numerically investigate the Betti numbers as a function of threshold level. Betti numbers are topological invariants of figures that can be used to distinguish topological spaces. In the case of the excursion sets of a three-dimensional field there are three possibly non-zero Betti numbers; β0 is the number of connected regions, β1 is the number of circular holes (i.e., complement of solid tori), and β2 is the number of three-dimensional voids (i.e., complement of three-dimensional excursion regions). Their sum with alternating signs is the genus of the surface of excursion regions. It is found that each Betti number has a dominant contribution to the genus in a specific threshold range. β0 dominates the high-threshold part of the genus curve measuring the abundance of high density regions (clusters). β1 dominates the genus near the median thresholds which measures the topology of negatively curved iso-density surfaces, and β2 corresponds to the low-threshold part measuring the void abundance. We average the Betti number curves (the Betti numbers as a function of the threshold level) over many realizations of Gaussian fields and find that both the amplitude and shape of the Betti number curves depend on the slope of the power spectrum n in such a way that their shape becomes broader and their amplitude drops less steeply than the genus as n decreases. This behaviour contrasts with the fact that the shape of the genus curve is fixed for all Gaussian fields regardless of the power spectrum. Even though the Gaussian Betti number curves should be calculated for each given power spectrum, we propose to use the Betti numbers for better specification of the topology of large scale structures in the universe.
The study focuses on the quality assessment of Black Bengal buck semen preserved at chilled condition. In this in vitro trial, collected semen from Black Bengal bucks was preserved at chilling temperature (4▲5줛) in tris-glucosecitrate yolk medium of 1:5 ratios for four days. Artificial Vagina (AV) method was utilized to collect semen from buck. General evaluation of semen includes the color, mass activity and density were measured by direct visual examination. However, computer-assisted sperm analysis (CASA) and phase contrast microscopy were used to figure out the motility (%), hyper-activated (HYP) motility (%) and number of abnormal spermatozoa (%) initially, and at every 24 h intervals. The result revealed that spermatozoa preserved at chilling temperature showed significantly (P<0.05) lower motility and HYP motility with the progression of preservation. The number of phenotypically abnormal spermatozoa significantly (P<0.05) increased following preservation. Although significant positive correlation (r=0.945; P<0.05) was existed between % motile and % HYP motile spermatozoa however, the % of morphologically abnormal spermatozoa was negatively correlated with % motile (r=긏0.997; P<0.05) and % HYP motile spermatozoa (r=긏0.946; P<0.01). Therefore, we concluded that the quality of chilled semen progressively losses its viability and doesn…t remain useable after certain period of preservation with respect to its motility and morphology.
This study investigated a developed process for producing a composite bipolar plate having excellent conductivity by using coal tar pitch and phenol resin as binders. We used a pressing method to prepare a compact of graphite powder mixed with binders. Resistivity of the impregnated compact was observed as heat treatment temperature was increased. It was observed that pore sizes of the GCTP samples increased as the heat treatment temperature increased. There was not a great difference between the flexural strengths of GCTP-IM and CPR-IM as the heat treatment temperature was increased. The resistivity of GPR700-IM, heat treated at 700℃ using phenolic resin as a binder, was 4829 μΩ·cm which was best value in this study. In addition, it is expected that with the appropriate selection of carbon powder and further optimization of process we can produce a composite bipolar plate which has excellent properties.
Apolipoprotein A1 (ApoA1) is the major protein component of high density lipoprotein (HDL) cholesterol in blood, and ApoA1 genetic polymorphisms modulate the blood lipid profiles. This study was conducted in order to investigate the association between three genetic polymorphisms (rs670, rs5069, and rs5070) of ApoA1 and blood lipid profiles in postmenopausal Korean women. A total of 130 post- menopausal women who visited a hospital in order to undergo screening tests were subjects of this study. Genetic polymporphisms and blood lipid profiles were determined using a direct sequencing and spectrophotometric assay, respectively. A significant linkage disequilibrium was observed between all tested single nucleotide polymorphisms. ApoA1 rs5070 genetic polymorphism showed a marginally significant association with HDL cholesterol levels (p=0.066). After adjusting for age, body mass index, smoking, alcohol drinking, medication, hypertension, and diabetes mellitus, we found that the ApoA1 rs5070 genetic polymorphism is a significant determinant of HDL cholesterol levels (β=4.421, p=0.037). According to the results of this study, ApoA1 rs5070 genetic polymorphism may be an important genetic marker associated with HDL cholesterol in postmenopausal Korean women.
Star clusters are superb astrophysical laboratories containing cospatial and coeval samples of stars with similar chemical composition. We initiate the Sejong Open cluster Survey (SOS) - a project dedicated to providing homogeneous photometry of a large number of open clusters in the SAAO Johnson-Cousins’ UBV I system. To achieve our main goal, we pay much attention to the observation of standard stars in order to reproduce the SAAO standard system.
Many of our targets are relatively small sparse clusters that escaped previous observations. As clusters are considered building blocks of the Galactic disk, their physical properties such as the initial mass function, the pattern of mass segregation, etc. give valuable information on the formation and evolution of the Galactic disk. The spatial distribution of young open clusters will be used to revise the local spiral arm structure of the Galaxy. In addition, the homogeneous data can also be used to test stellar evolutionary theory, especially concerning rare massive stars. In this paper we present the target selection criteria, the observational strategy for accurate photometry, and the adopted calibrations for data analysis such as color-color relations, zero-age main sequence relations, Sp - MV relations, Sp - Teff relations, Sp - color relations, and Teff - BC relations. Finally we provide some data analysis such as the determination of the reddening law, the membership selection criteria, and distance determination.
Isotropic pitch fibers were stabilized and carbonized for preparing carbon fibers. To optimize the duration and temperature during the stabilization process, a thermogravimetric analysis was conducted. Stabilized fibers were carbonized at 1000, 1500, and 2000℃ in a furnace under a nitrogen atmosphere. An elemental analysis confirmed that the carbon content increased with an increase in the carbonization temperature. Although short graphitic-like layers were observed with carbon fibers heat-treated at 1500 and 2000℃, Raman spectroscopy and X-ray diffraction revealed no significant effect of the carbonization temperature on the crystalline structure of the carbon fibers, indicating the limit of developing an ordered structure of isotropic pitch-based carbon fibers. The electrical conductivity of the carbonized fiber reached 3.9×10⁴S/m with the carbonization temperature increasing to 2000℃ using a four-point method.
Canine parvovirus (CPV2) is one of the most virulent virus causing acute hemorrhagic enteritis and myocarditis in dogs. Infection mainly caused by the ingestion of virus through the mucosal route. Therefore, induction of mucosal immunity is essential in prevention of Canine Parvovirus (CPV2) infection. For safe and effective delivery of viral antigens to the mucosal immune system, a novel surface antigen display system for lactic acid bacteria using the poly-γ-glutamic acid synthetase A protein (pgsA) of Bacillus subtilis as an anchoring matrix was applied in order to display CPV2 antigen on the surface of the recombinant L. casei. Recombinant fusion proteins comprised of pgsA and the capsid protein (VP2-S1) showed stable expression in Lactobacillus casei. Surface localization of the fusion protein was verified by cellular fractionation analyses. Oral and nasal inoculations of recombinant L. casei into mice resulted in high levels of serum immunoglobulin G (IgG) and mucosal IgA, as demonstrated by ELISA using recombinant VP2-S1 proteins. Mice receiving intranasal immunization mounted higher antibody response than those receiving oral immunization. These results indicate that mucosal immunization with recombinant L. casei expressing CPV2 VP2-S1 protein on its surface provides an effective means for elicitation of strong antibody responses against CPV 2 VP2-S1.
The recent development in genetic assisted selection (combining traditional- and genome assisted selection method) and reproduction technologies will allow multiplying elite cow in Hanwoo small farm. This review describes the new context and corresponding needs for genome assisted selection schemes and how reproductive technologies can be incorporated to get more genetic gain for cow genetic improvement in Hanwoo. New improved massive phenotypes and pedigree information are being generated from commercial farm sector and these are allowing to do genetic evaluation using BLUP to get elite cows in Korea. Moreover cattle genome information can now be incorporated into breeding program. In this context, this review will discuss about combining the reproductive techniques (Multiple Ovulation Embryo Transfer; MOET) and genome assisted selection method to get more genetic gain in Hanwoo breeding program. Finally, how these technologies can be used for multiplication of elite cow in small farm was discussed.
Haploids are plants with a gametophytic number of chromosomes in their sporophytes. Androgenesis occurs from asymmetric division of pollen grains into generative cells and vegetative cells, followed by re-entry of the vegetative cell during S-phase, which causes microspores progress into G2/M transition in culture. One of the most interesting features of haploids is the possibility to produce doubled haploid (DH) individuals. Doubled haploidy is extremely useful to plant breeders because it enables shortened breeding periods and efficiency in selection of useful recessive agronomic traits. Doubled-haploid technology is not only applicable to breeding, but also to transformation programs of desired genes. In addition to practical breeding programs, DH lines provide useful materials of fundamental genetics including exploitation of QTLs and genes conferred with various agronomic traits by establishing DH populations. This paper provides historical overviews on androgenesis and describes several mechanisms associated with pollen embryogenesis, including mode of actions in pollen embryogenesis, mechanisms of chromosome doubling and factors affecting androgenesis. We also discuss recent progress in application of haploids to breeding, genes associated with in vitro response and drawbacks to anther culture for application of doubled haploids in crop breeding.
A total of 35 phosphate solubilizing bacterial strains were isolated from waste mushroom bed of Agar-icus bisporus in Buyeo-Gun, Chungnam and screened for the production of indole acetic acid (IAA). The best IAAproducing strain was identified as Pantoea rodasii using 16S rRNA analysis. In addition to the IAA production, thisstrain could act as an efficient phosphate solubilizer (1100µg ml-1 after 5days of incubation) also. The selected strainwas cultured under different conditions in order to assess the optimum conditions for maximum IAA production. Thenutrient broth (NB) medium was recorded as the best medium, where the maximum IAA production (229µg ml-1)was recorded at the start of stationary phase (12hours after inoculation) of the bacteria growth. The performanceof the strain was found to be maximum at the temperature of 30℃ followed by 25℃. IAA production was foundto be increased with increasing tryptophan concentration (from 0.1 to 0.6%), however beyond this limit, a slight reduc-tion in IAA production was observed. The strains’ ability to produce IAA was further confirmed by extraction ofcrude IAA and subsequent TLC analysis. A specific spot from the extracted IAA preparation was found correspondingwith the standard spot of IAA with same Rf value. The results of HPLC analysis conducted in identifying and quan-tifying the IAA production more precisely, are in agreement with the results of the assessment done with colorimetricmethod. As revealed by the results of the pot experiment, the isolated strain could significantly enhance the growth(as measured by shoot and root growth) of mung bean plants compared to that of non-inoculated plants. Thereforeit can be concluded that the present strain, Pantoea rodasii has great potential to be used as bio-inoculants.