• Title/Summary/Keyword: Nanos

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A Study on the Development of an Early Embryonic Gene of the Silkworm, Bombyx mori (누에 배형성기 초기 발현 유전자 개발 연구)

  • Choi, Kwang-Ho;Goo, Tae-Won;Kim, Seong-Ryul;Park, Seung-Won;Kim, Sung-Wan;Kang, Seok-Woo
    • Journal of Sericultural and Entomological Science
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    • v.50 no.2
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    • pp.122-125
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    • 2012
  • This study was aimed for a development of a useful gene promoter which has a transcript expressional specificity in the early embryonic period of the silkworm, Bombyx mori. To select a useful gene expressed in the early embryonic stage, we constructed and analyzed a PCR-base subtraction cDNA library. In subtractive hybridization analysis, we confirmed four clones as differently expressed genes(BmNanos-like, BmNanos-P, BmNanos-O, BmVasa mRNAs). Northern hybridization and real time PCR results reveled that the BmNanos-like gene promoter is suitable for the silkworm transgenic vector system. Further defined studies on molecular functions and biological roles of their promoters will give us well-fined information and its application.

Proteins as the molecular markers of male fertility

  • Beeram, Eswari
    • The Korean Journal of Food & Health Convergence
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    • v.4 no.4
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    • pp.18-25
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    • 2018
  • Proteins play a key role in many functions such as metabolic activity, differentiation, as cargos and cell fate regulators. It is necessary to know about the markers involved in male fertility in order to develop remedies for the treatment of male infertility. But, the role of the proteins is not limited to particular function in the biological systems. Some of the proteins act as ion channels such as catsper and proteins like Nanos acts as a translational repressor in germ cells and expressed in prenatal period whose role in male fertility is uncertain. Rbm5 is a pre mRNA splicing factor necessary for sperm differentiation whose loss of function results deficit in sperm production. DEFB114 is a beta defensin family protein necessary for sperm motility in LPS challenged mice where as TEX 101 is a plasma membrane specific germ cell protein whose function is not clearly known u to now. Gpr56 is another adhesion protein whose null mutation leads to arrest of production of pups in rats. Amyloid precursor protein role in Alzheimer's disease is already known but it plays an important role in male fertility also but its function is uncertain and has to be considered while targeting APP during the treatment of Alzheimer's disease. The study on amyloid precursor protein in male fertility is a novel thing but requires further study in correlation to alzheimer's disease.

Ceramic Coating by Electron Beam PVD for Nanos-Tructure Control (나노구조 제어를 위한 EB-PVD법에 의반 세라믹스 코팅)

  • Matsbara, Hideaki
    • Ceramist
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    • v.9 no.6
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    • pp.24-29
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    • 2006
  • Electron beam physical vapor deposition (EB-PVD) process has currently been applied to thermal barrier coatings (TBCs) for aircraft engines. Due to unique columnar structure, EB-PVD TBCs have advantages in resistances to thermal shock and thermal cycle for their applications, compared to films prepared by plasma spray By the EB-PVD equipment, we successfully obtained yttria-stabilized zirconia (YSZ) layer which has columnar and feather like structure including a large amount of nano size pores and gaps. The EB-PVD technique has been developed for coating functional perovskite type oxides such as (La, Sr)MnO3. Electrode properties have been improved by interface and structural control.

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Effect of CuO on the Optical and Structural Properties of Phosphate Glass for Near-Infrard Filter (근적외선 필터용 인산계 유리의 광학적 특성 및 구조적 특성에 미치는 CuO 의 영향)

  • Kim, Seong-Il;Hwang, Jong-Hee;Lim, Tae-Young;Kim, Jin-Ho;Kim, Young-Ho;Lee, Jong-Hwa;Choi, Deuk-Kyun
    • Korean Journal of Materials Research
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    • v.19 no.12
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    • pp.657-660
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    • 2009
  • Optical characteristics and structural changes depending on CuO content in phosphate glasses that are used in near-infrared (near-IR) filters were investigated. With phosphate glasses that contain 1-9 mol% CuO, changes in optical transmittance, optical absorption, and color coordinate were measured with a UV-VIS spectrophotometer. An XPS (X-ray photoelectron spectroscopy) analysis was performed to determine valence of copper ion that influences optical characteristics in near-IR filter glasses. Structural changes in glasses depending on CuO content were also analyzed by FT-IR (Fourier transform infrared) and Raman spectrophotometers. From the UV-VIS spectrophotometer results, strong absorption peaks at 220 & 900 nm were found and transmittance was decreased. The color coordinates of the glasses were shifted to the green color direction with CuO addition for increasing absorption of long wavelength range spectra, in spite of the amount of $Cu^{2+}$, which gives a blue color to glasses, and which was increased in XPS results. Also, structural de-polymerization of glasses with CuO addition were found by FT-IR and Raman results.

A Study on Plastic Injection Molding of NanosStructured Surface with a Local Mold Heating System (국부 가열 금형을 이용한 플라스틱 나노 구조표면 사출성형 연구)

  • La, Moon Woo;Park, Jang Min;Kim, Dong Earn
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.14 no.4
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    • pp.8-13
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    • 2015
  • In this study, we fabricated and characterized a nanostructured surface based on a plastic injection molding with a local mold heating (LMH) system. A metal mold core with a closed packed nano convex array (CVA) was achieved by integrated engineering procedures: (1) master template fabrication by anodic aluminum oxidation (AAO), (2) nickel electroforming (NE) process, and (3) post-processing by precision machining. The nickel mold core was utilized to replicate a surface with a closed packed nano concave-array (CCA) based on injection molding using cyclic olefin copolymer (COC) as a plastic material. In particular, an LMH system was introduced to enhance transcription quality of the nano structures by delaying solidification of molten polymer near the surface of the mold core.

Assessment of infill wall topology contribution in the overall response of frame structures under seismic excitation

  • Nanos, N.;Elenas, A.
    • Structural Engineering and Mechanics
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    • v.53 no.2
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    • pp.355-372
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    • 2015
  • This paper identifies the effects of infill wall existence and arrangement in the seismic response of steel frame structures. The methodology followed was based on the utilisation of overall seismic response indicators that distil the complexity of structural response in a single value hence enabling their straightforward comparative and statistical post process. The overall structure damage index after Park/Ang ($OSDI_{PA}$) and the maximum inter-story drift ratio (MISDR) have been selected as widely utilized structural seismic response parameters in contemporary state of art. In this respect a set of 225 Greek antiseismic code (EAK) spectrum compatible artificial accelerograms have been created and a series of non-linear dynamic analyses have been executed. Data were obtained through nonlinear dynamic analyses carried on an indicative steel frame structure with 5 different infill wall topologies. Results indicated the significant overall contribution of infill walls with a reduction that ranged 35-47% of the maximum and 74-81% of the average recorded $OSDI_{PA}$ values followed by an overall reduction of 64-67% and 58-61% for the respective maximum and average recorded MISDR values demonstrating the relative benefits of infill walls presence overall as well as localised with similar reductions observed in 1st level damage indicators.

Application of Ultrafast Laser for Micro-packaging and Germanium Surface Processing (초고속레이저 기반 마이크로 패키징 및 게르마늄 표면 공정 기술 개발)

  • Jeoung, S.C.;Yahng, J.S.
    • Journal of the Korean Vacuum Society
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    • v.16 no.1
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    • pp.74-78
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    • 2007
  • Much interests has been drawn for noble micro-engineering processes for the continuous size reduction on bulk materials from the field of micro-electronics with much downsized IC chips. A traditional microprocessing based on mechanical blade as well as a relatively long pulsed laser usually influence the physico-chemical properties of intact materials when the techniques are applied to process materials with a spatial resolution less than 10 microns. Meanwhile, ultrafast laser pulses are known to exhibit a very small heat-affect zone(HAE) compared to the traditional laser processing and to be applicable for the new functional materials with high performance in optical and electrical properties. In this report, we will review in brief the recent research works on the enhancement of micro-cutting speed of thin silicon wafer as well as the formation of Ge nanostructures based on ultrafast laser pulses.

Effects of different culture systems on the culture of prepuberal buffalo (Bubalus bubalis) spermatogonial stem cell-like cells in vitro

  • Li, Ting-Ting;Geng, Shuang-Shuang;Xu, Hui-Yan;Luo, Ao-Lin;Zhao, Peng-Wei;Yang, Huan;Liang, Xing-Wei;Lu, Yang-Qing;Yang, Xiao-Gan;Lu, Ke-Huan
    • Journal of Veterinary Science
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    • v.21 no.1
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    • pp.13.1-13.14
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    • 2020
  • Currently, the systems for culturing buffalo spermatogonial stem cells (SSCs) in vitro are varied, and their effects are still inconclusive. In this study, we compared the effects of culture systems with undefined (foetal bovine serum) and defined (KnockOut Serum Replacement) materials on the in vitro culture of buffalo SSC-like cells. Significantly more DDX4- and UCHL1-positive cells (cultured for 2 days at passage 2) were observed in the defined materials culture system than in the undefined materials system (p < 0.01), and these cells were maintained for a longer period than those in the culture system with undefined materials (10 days vs. 6 days). Furthermore, NANOS2 (p < 0.05), DDX4 (p < 0.01) and UCHL1 (p < 0.05) were expressed at significantly higher levels in the culture system with defined materials than in that with undefined materials. Induction with retinoic acid was used to verify that the cultured cells maintained SSC characteristics, revealing an SCP3+ subset in the cells cultured in the defined materials system. The expression levels of Stra8 (p < 0.05) and Rec8 (p < 0.01) were significantly increased, and the expression levels of ZBTB16 (p < 0.01) and DDX4 (p < 0.05) were significantly decreased. These findings provided a clearer research platform for exploring the mechanism of buffalo SSCs in vitro.