우리나라 사과 재배에 가장 널리 이용되는 수형은 세장방추형으로 수령이 증가함에 따라 수관 내부의 광환경이 불량해진다. 전정을 통한 부분적인 수관 변경은 이러한 문제점 개선의 효율적인 대안이라고 할 수 있다. 본 연구는 이와 관련하여 나무 중간의 수관 변경에 따른 수관 내 광환경의 변화를 살펴보고, 과실 품질 향상을 위한 적절한 측지 관리 방법을 모색하고자 4.0 × 1.5m로 재식된 ‘감홍’/M.9을 대상으로 2년간 시험을 수행하였다. 처리 1은 측지를 짧게 단축하여 수관 폭을 좁게 만드는 것이었고, 처리 2는 측지를 유인하는 것이었으며, 처리 3은 대조구로 기존 세장방 추형의 수관을 유지했다. 1. 처리 1은 수관 하부로의 광투과율이 가장 높았고 기존 세장방추형에 비해 과중과 착색도가 높은 과실의 생산이 가능 했으며 높은 꽃눈 분화를 나타냈다. 2. 처리 2는 유인에 따라 가지의 중첩에 의한 음영 발생 증 가로 광투과율이 오히려 감소하였고 이에 따라 과실 착색의 저하를 초래하였다. 3. 따라서 광환경 개선과 하부의 과실 품질 향상을 위한 가 장 효율적인 측지 관리 방법은 중간에 위치한 측지를 길이 50 cm 내로 단축 전정하여 수관 폭을 좁게 유지하는 것으로 판단되었다.
Forged part made of Cold heading quality wire materials are used for automotive brake systems. The cost reduction of forged products is a major issue because of the strict shape change. A series of studies were conducted to minimize the cost of EPB spindle process among brake parts. In order to reduce the material cost, heat treatment-abbreviated material was applied and the formability on the processes was verified by the ductile fracture theory. In addition, the causes of shape fixation and die life degradation were analyzed using the numerical simulation. The process cost has been minimized by re-designing process, changing the product shape, and the die material.
Unlike somatic cells mitosis, germ cell meiosis consists of two consecutive rounds of divisions that segregate homologous chromosomes and sister chromatids, respectively. The meiotic oocyte is characterized by an absence of centrioles and asymmetric divisions. Centriolin is a relatively novel centriolar protein that functions in mitotic cell cycle progression and cytokinesis. Here, we explored the function of centriolin in meiosis and showed that it was localized to meiotic spindles, and concentrated at the spindle poles and midbody during oocyte meiotic maturation. Unexpectedly, knockdown of centriolin in oocytes with either siRNA or Morpholino micro-injection, did not affect meiotic spindle organization, cell cycle progression, or cytokinesis (as indicated by polar body emission), but led to a failure of peripheral meiotic spindle migration; and symmetric division or large polar body emission. These data suggest that, unlike in mitotic cells, the centriolar protein centriolin does not regulate cytokinesis, but plays an important role in regulating asymmetric division of meiotic oocytes.
Mitotic spindle formation is regulated by centrosomes, composed of a centriole pair surrounded by pericentriolar materials(PCM) proteins. However, mammalian oocytes rely on acentriolar MTOCs for the function of meiotic spindle. The composition of acentriolar MTOCs and the molecular precesses that regulate the localization and accumulation in mammalian oocyte are not well understood. In this study, we analyzed the mechanisms of spindle microtubule nucleation and stability from MTOCs in mouse oocyte, and indentified Centrosomal protein192(CEP192) as a key regulator for acentriolar MTOC formation. CEP192 specifically colocalized with pericentrin (PCNT) during the oocyte maturaion. CEP192 proteins are localized throughout cytoplasm and around nucleus at GV stage, and then after BD stage, CEP192 proteins were further fragmented into smaller MTOCs around chromosomes. At metaphase, CEP192 proteins were concentrated in spindle pole. Knockdown of CEP192 using siRNAs resulted in metaphase I arrest. The arrested oocytes were characterized by reduced microtubule intensity and misalignment chromosome. Also at BD and ProMI stage, the oocytes reduced microtubule density and PCNT intensity. To confirm the mechanism of CEP192 regulation, we confirmed that PLK1 and AuroraA kinase were involved in CEP192 activation. The investigations for detailed molecular mechanisms of CEP192 and RanGTP for microtubule nucleation in oocytes are underway using various techniques including siRNA, mRNA, and positive or negative dominant injection and inhibitors.
Carbon nanofiber (CNF) composites coated with spindle-shaped Fe2O3 nanoparticles (NPs) are fabricated by a combination of an electrospinning method and a hydrothermal method, and their morphological, structural, and chemical properties are measured by field-emission scanning electron microscopy, transmission electron microscopy, Xray diffraction, and X-ray photoelectron spectroscopy. For comparison, CNFs and spindle-shaped Fe2O3 NPs are prepared by either an electrospinning method or a hydrothermal method, respectively. Dye-sensitized solar cells (DSSCs) fabricated with the composites exhibit enhanced open circuit voltage (0.70 V), short-circuit current density (12.82 mA/cm2), fill factor (61.30%), and power conversion efficiency (5.52%) compared to those of the CNFs (0.66 V, 11.61 mA/cm2, 51.96%, and 3.97%) and spindle-shaped Fe2O3 NPs (0.67 V, 11.45 mA/cm2, 50.17%, and 3.86%). This performance improvement can be attributed to a synergistic effect of a superb catalytic reaction of spindle-shaped Fe2O3 NPs and efficient charge transfer relative to the one-dimensional nanostructure of the CNFs. Therefore, spindle-shaped Fe2O3-NPcoated CNF composites may be proposed as a potential alternative material for low-cost counter electrodes in DSSCs.
This study is to develop a core part Spindle and Nut Spindle of the electronic parking brake system. This demand is the development and launch notification referral order also commissioned state. Domestic competitors company developed and applied to workpiece of Spindle and Nut Spindle. In this study, the market advertisement is aimed over its competitors by developing cost competitiveness and quality stability through parts and components of precision forging engineering. Thus, axle measuring device system is needed to verify the reliability(fastening state of brake system) at the same time the development of Spindle and Nut Spindle. This study is performed to the following four aims. The first is the development of forging process technology for Spindle and Nut Spindle. The second is the development of mold design technology for Spindle and Nut Spindle. The third is the reliability secured technology for axle force(brake system force) of electronic brake system. The last is the development of forging and shape design simulation of Spindle and Nut Spindle.
고등식물은 고정된 장소에 서식하기 때문에 주변 환경의 오염에 따른 부정적 영향을 회피할 수 없다. 대기 오염 지역과 청정지역에 서식하는 가로수의 이온화 방사선에 대한 효소활성 변화를 이용하여 대기오염 정도를 진단하는 방법을 개발하고자 본 연구를 수행하였다. 오염된 대기 속에 서식하며 대기에 포함된 오염물질로부터 지속적으로 산화스트레스를 받아온 식물체의 경우 이를 극복하기 위한 수단으로 생화학적 저항성을 발달시키게 된다. 항산화 효소와 자유라디칼 제거능,
목 적: 본 연구에서는 CA(Cellulose Acetate; CA)안경테 전용 가공장비의 40,000 rpm급 고속 주축시스템에 대하여 구조설계 단계에서 안정성을 검토하였다. 방 법: 안경테 전용 주축시스템의 베어링 윤활과 예압구조 선정 및 주축계의 정/동/열적 특성 분석을 통하여 고유진동수, 최대변형, 열변위를 예측하였다. 결 과: 안경테 가공장비 주축의 윤활시스템은 최소미량급유방식인 오일-에어 방식을 채택하였으며 정동적분석 결과 안정성이 확보되었으나, 열변위량은 최대 0.135 mm로 고속 회전 시 주축 발란싱과 성능에 문제가 발생 할 것으로 예측되었다. 결 론: CA안경테 전용 가공장비의 40,000 rpm급 고속 주축시스템을 설계 단계에서부터 윤활 및 예압구조를 선정하였으며, 정동적분석을 통하여 구조안정성이 우수함을 예측하였다. 그러나 회전에 따른 열상승 및 열적변형에 취약하여 이에 대한 대책이 필요할 것으로 나타났다.
In the present study, effects of concentration and time of culture in presence of roscovitine on nuclear maturation and meiotic spindle configuration, chromosomal alignment were examined in porcine oocytes. In experiment 1, porcine cumulus oocyte complexes (COCs) were cultured at in a 5% atmosphere in North Carolina State University 23 (NCSU-23) supplemented with 25, 50, 75 or roscovitine for 22 h and then were cultured for additional 22 h after removal of roscovitine. Nuclear maturation and morphology of the meiotic spindle and chromosomal alignment were examined to determine the optimal concentration of roscovitine in oocyte maturation. In experiment 2, COCs were cultured in NCSU-23 supplemented with roscovitine for 17, 20, 27 or 42 h and then an additional 22 h without roscovitine was followed to determine the optimal time of culture. The optimal concentration of roscovitine to arrest and resume meiosis of porcine oocyte was by examining nuclear status (p<0.05) and normal spindle and chromosome configuration. The optimal time of culture in presence of roscovitine to arrest meiosis of porcine oocyte was 17 h (p<0.05), although MII rates and normal morphology of the meiotic spindle and chromosomal alignment were not significantly different among various times of culture. In conclusion, the optimal concentration and time of culture in presence of roscovitine to arrest porcine oocytes are and 17 h, respectively.
재식거리 3.2×1.2m로 심어 수고 2.5m의 세장방추형으로 관리해 오던 '후지'/M.9 사과나무를 재식 6년차부터 2년 동안 수고 4.0m로 관리하였다. 이후 재식 8년차에 수고를 2.5m(대조구), 3.0m, 3.5m, 4.0m로 조절하고 수고에 따른 2년간의 생산성 및 노동력을 비교하였다. 대조구인 수고 2.5m를 기준으로 하여 처리에 따른 10a당 생산량을 비교해 보면 첫해에는 수고 4.0m, 3.5m, 3.0m에서 각각 46%, 25%, 4%, 2년차에는 17%, 12%, 10% 증가하였다. 수고에 따른 과실 품질에 있어서는 가용성 고형물 함량은 2개년 모두 수고 2.5m가 가장 높았으나, 착색정도는 수고에 따른 뚜렷한 차이가 없었다. 노동력은 수고가 높아질수록 증가하였으나, 노동력에 따른 과실생산량은 수고가 낮을수록 증가하였다. 조수입과 순수입은 2005년의 경우 수고가 높아질수록 증가하였으나, 2006년은 수고 2.5m가 가장 높았지만 통계적 유의차는 없었다. 따라서 수고에 따른 생산성, 노동력, 경제성을 고려해 볼때 적정수고는 3.0~3.5m인 것으로 판단되었다.
The purpose of this study was to determine the effects of Taxol pre-treatment to in vitro matured bovine oocytes, and sucrose and trehalose added to vitrification solution on spindle morphology and embryonic development following cryopreservation. Bovine oocytes were collected from ovaries and matured in tissue culture medium 199 (TCM 199) supplemented with 10% Fetal Bovine Serum (FBS), 0.05ng/ml epidermal growth factor, 0.01 IU/ml luteinizing hormone and estradiol for 22h in , 5% , TCM 199-HEPES containing 20% FBS was used as basic medium (BM) to prepare vitrification solution. Oocytes were pre-treated with Taxol in maturation medium for 15 min prior to vitrification. Oocytes were exposed to 1.6 M ethylene glycol (EG) and 1.3M dimethyl sulfoxide (DMSO) in BM and then were exposed to 3.2 M EG, 2.6 M DMSO and 0.5 M sucrose in BM or 3.2 M EG, 2.6 M DMSO and 0.5 M trehalose in BM. Oocytes with cumulus cells and oocytes without cumulus cells were considered as control 1 and control 2, respectively and held in TCM 199-HEPES at . Oocytes were frozen using modified solid surface vitrification and were stored in cryotubes in liquid nitrogen for more than 1 week. Frozen oocytes were thawed in TCM 199-HEPES containing 0.5 M, 0.25 M and 0.1 M sucrose in BM for 2 min, respectively or 0.5 M, 0.25 M and 0.1 M trehalose in BM for 2 min, respectively. Immunoflurorescence staining of oocytes was performed to assess spindle morphology and chromosome configuration of oocytes. The rates of cleavage and blastocyst were examined following in vitro fertilization. Normal spindle morphology rate of oocytes pre-treated with Taxol prior to vitrification was not higher than that of other vitrified groups. Taxol pre-treatment did not increase cleavage and blastocyst formation rates, although control groups showed significantly higher rates (p<0.05). Percentages of normal spindle and embryonic development were not significantly different among vitrified groups regardless of type of sugar. In conclusion, Taxol pre-treatment of oocytes before cryopreservation did not reduce the damage induced by vitrification and subsequently did not improve embryonic development following vitrification. Trehalose may be used as an alternative non-permeating cryoprotectant in vitrification solution.
'후지'/M.9에 대한 세장방추형에 적합한 하단측지수 구성을 위하여 하단측지수를 달리하여 수체생육, 광환경, 수량 및 과실품질을 조사하였다. 하단측지수준별 생육은 하단측지수를 5개로 유지했을 때 수폭은 넓었고, 신초장 및 정단신초장은 증가하였다. 수관위치별 수광률은 하단측지수가 5개인 처리구에서 수관상부(지상 150cm)와 수관중부(지상 100cm)에서는 높은 경향을 보였다. 총 단과지 화아수는 측지수에 따라 차이가 없었으나, 수관위치별로 보면 수관하부(지상 120cm 이하)에서 하단측지수가 5개 처리에서 가장 많았으며, 화아의 횡경도 커지는 경향이었다. 과실수량은 하단측지수가 5개에서 가장 많았고, 과중은 하단측지수가 5개와 8개에서 증가하는 경향이었다. 과실특성은 과형지수, 경도, 산함량, Hunter L, b값은 수관위치와 측지수준에 따라 차이가 없었으나, 가용성고형물 함량은 하단측지수가 5개일 때 높았다. 과실의 착색도를 나타내는 Hunter a값은 수광률이 가장 높은 하단측지수를 5개로 유지한 처리구에서 가장 높게 나타났다.
동결 과정 중 필수적인 단계중 하나인 냉각(cooling)과 냉각 후 배양시간이 생쥐 난자의 방추체의 형태와 염색체의 배열에 미치는 영향을 알아봄으로서 냉각 후 손상되었던 난자의 방추체와 염색체가 정상적으로 회복하는데 필요한 최적의 배양시간을 알아보기 위해 본 실험을 실시하였다. 생후 4-6주령의 암컷 B6C3Fl 생쥐를 과배란 처리하여 metaphase II상태의 난자를 회수하여 다음과 같이 처리하였다. 대조군은 난자를 냉각처리하지 않았으며 실험군은