• Title/Summary/Keyword: Phase transfer

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Study on Production of Cloned Animals by Recycling Nuclear Transplantation III. Production of Third Generation Cloned Embryos in Rabbits (반복핵이식에 의한 복제동물 생산에 관한 연구 III. 토끼에서 제3세대 복제수정란의 생산)

  • Lee Hyo-jong;Jeon Byeong-gyun;Yin Xi-jun;Park Choong-saeng;Choe Sang-yong;Yun Chang-hyun;Kang Dae-jin
    • Journal of Veterinary Clinics
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    • v.12 no.1
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    • pp.877-886
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    • 1995
  • The recycling nuclear transplantation(NT) technique has the powerful potential of producing a large number of genetically identical embryos and offsprings from one embryo. Multiple generational cloning by this technique utilizes the NT embryo itself as the donor for the next generation of cloning. In this experiment, we have produced the third generational cloned embryos by recycling NT. Further we examined comparatively the electrofusion rate and in vitro developmental potential in the cloned embryos of the first second and third generations. The embryos of 16-cell stage were collected from the mated does by flushing oviducts with Dulberco's phosphate buffered saline containing 10 % fetal calf serum(FCS) at 47 hours after hCG injection. In the first generation NT, the nuclear donor embryos were synchronized in the phase of Gl/S transition of 32-cell stage. The first and second generation NT embryos developed to 16-cell were used as donor nuclei for second and third generation. The recipient cytoplasms were utilized the oocytes collected at 14 hours after hCG injection, following revoming the nucleus and the first polar body by micromanipulation. The separated blastomeres were injected into the enucleated recipient oocytes by micromanipulation and were fused by electrical stimulation. The electrofusion rate was seen to be 78.0, 88.0 and 90.3 % in the first second and third generation NT rabbit embryos, respectively. The fused oocytes were co-cultured with a monolayer of rabbit oviductal epithelial cells in M-199 solution containing 10 % FCS for 120 hours at 39$^{\circ}C$ in a 5% $CO_2$ incubator. The in vitro developmental potential to blastocyst stage was significantly(P<0.05) decreased in the third(7.2 %) generation NT embryos compared to the first(53.1 %) and second(16.1 %) generation NT embryos. Following in vitro development to blastocyst stage, they were stained with Hoechst 33342 dye for counting the number of blastomeres by fluorescence microscopy. The mean blastomere numbers and cell cycle numbers of NT embryos during the culture period were significantly(p<0.05) decreased in the second(93.9 cells and 6.55 cylces) and third(81.5 cells and 1.35 cylces) generation, compared to the first(189.9 cells and 7.55 cylces) generation.

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A Study on the Development of SSB Modem (디지털 SSB 모뎀 개발에 관한 연구)

  • Kim, Jeong-Nyun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.11 no.10
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    • pp.1852-1857
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    • 2007
  • The SSB modem performs the modulation process which converts the digital voltage level to the audible frequency band signal and the demodulation process which converts reversely the audible frequency signal to the digital voltage level. The modulator and the demodulator are implemented with a single DSP chip. Because of the SSB specific character, the distortion occurs when the frequency is changed. This distortion has no effect on voice communication but it has an significant effect on data communication. In other words, it is impossible to send data stream with adjacent 2 periods. Therefore, in case of using 2-tone FSK, it is needed to send at least 3 periods to transmit 1 bit. Therefore we implemented the modem using modified phase-delay shift keying to transmit 1 tone signal for high speed transmission. In the 1200[bps] mode, it generates 0, $187{\mu}s$, delay time at 1.3kHz symbol frequency, and in the 2400[bps] mode, 0, $70{\mu}s\;130{\mu}s\;200{\mu}s$, delay time at 1.5kHz symbol frequency. Finally, in the maximum 3600[bps] mode, it generates 0, $100{\mu}s\;160{\mu}s\;250{\mu}s$ 2.0kHz symbol frequency. The measured results of the implemented SSB modem shows a good transfer functional characteristic by spectrum analyzer, almost same bandwidth in pass band and 20dB higher SNR comparing the emu FACTOR and American CLOVER and in the experimental transmitting test, we verified the transmitted data is received correctly in platform.

The Numerical Study on Effect of the Droplet Sizes on Internal Mass Transfer in the Spray Type Scrubber (분무형 스크러버에 내에서 액적크기에 따른 물질전달에 관한 전산해석적 연구)

  • Lee, Chanhyun;Chang, Hyuksang
    • Clean Technology
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    • v.25 no.1
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    • pp.19-32
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    • 2019
  • As regional air pollution gets worse by the sulfur oxides emitted from various types of vessels passing through the many countries, the International Maritime Organization establishes the emission control areas and regulates sulfur dioxide in those areas. In order to satisfy these regional regulations, the fuel selection method and the exhaust gas post-treatment device are applied to the ships. Due to the economic reasons, the post-treatment method of exhaust gas for reducing the amount of sulfur oxides discharged is mainly preferred. The scrubber which is dominantly used in the ships are the spray type system where the sprayed liquid drops used for capturing the soluble sulfur dioxides in the exhaust gas. The performance of the spray type system depends on the size distribution of the sprayed droplets. In order to evaluate this performance, we designed counterflow type scrubber and cyclone scrubber and evaluated the desulfurization efficiency and the amount of droplet evaporation according to the size of each droplet by using computational fluid dynamics. The Eulerian-Eulerian analysis method was used because the scrubber had a gas-liquid two-phase flow inside the scrubber. When the diameter of the droplet was $100{\mu}m$, $300{\mu}m$, $500{\mu}m$ and $700{\mu}m$. As a result, both of scrubbers showed high desulfurization efficiency and low evaporation amount at $500{\mu}m$ and $700{\mu}m$.

A Study on Counseling Process and Counseling Techniques Applying Analytical Psychology (분석심리학을 적용한 상담과정과 상담기법에 관한 연구)

  • Park, Won-Jin;Kim, Bo-Ki
    • Industry Promotion Research
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    • v.4 no.1
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    • pp.67-78
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    • 2019
  • This study is to study Jung's analytical psychology and to study counseling process and counseling techniques based on the counseling theory derived from it. Jung divides the counseling process into four stages based on analytical psychology. The first stage is confession, and the prototype of analysis therapy is confession. The first step in the treatment process is to share secrets and reveal suppressed emotions. The second stage is elucidation, a process that clarifies by shedding light on the contents induced by the transfer. The third stage is the level of education. Explanation makes my counselors intelligent, but leaves them still in an incompetent state. At this stage, treatment goes beyond insight to train as a responsible client. The fourth stage is transformation. In the transformation phase with inner counselors, not only the debaters, but also the therapist is in the "in-analysis." Jung's counseling technique uses six things: dream analysis, use of symbols, word link test, symptom analysis, case history and MBTI. In conclusion, analytical psychology counseling has enabled, first, a more in-depth approach and understanding of the human mind, especially the unconscious world. Second, analytical psychology counseling has enabled us to recognize that all humans are human communities with a common mental structure through the concept of unconsciousness and archetypes. Third, analytical psychology counseling has allowed you to look at the meaning and purpose of life from a new perspective. Therefore, Jung emphasized that he should not be seen as having a pathological problem with patients, but as an omnipotent human being who wants to realize its fullness on his own.

Prototyping a BIM-enabled Design Tool for the Auto-arrangement of Interior Design Panels - Based on the Pattern Extraction of Bitmap Image Pixels and its Representation - (BIM기반 설계를 지원하는 인테리어 패널 자동배치 도구 프로토타입 구현 - 비트맵 이미지 픽셀 패턴의 추출과 패널 표현을 중심으로 -)

  • Huang, JinHua;Kim, HaYan;Lee, Jin-Kook
    • Design Convergence Study
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    • v.15 no.5
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    • pp.71-83
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    • 2016
  • Interior panels are usually used in finishing of interior walls for not only decorative effects but also information transfer. According to designer's design placing interior panels may need repetitive tasks and the emphasis of this paper is to support an automation of these tasks. Considering the utilization characteristics of interior panels, we propose three method to present patterns by using bitmap image pixels and interior panels' shape changes, based on the theoretical consideration. In addition, in order to approve the possibility of the proposed methods, we have implemented the BIM based interior panels auto layout tool which applied one of the three methods to present patterns by using bitmap image pixel values and panel identification attributes. This tool also supports auto generation of quantity and panel arrangement sequence information that will be used in future construction phase. We expect that this approach will also be used in other decorative objects which require repetition of the basic units, such as floor tiles.

Strain Improvement and Bioprocess Optimization for Enhanced Production of Haluronic Acid(HA) in Bioreactor Cultures of Streptococcus zooepidemicus (히알루론산 생산성 향상을 위한 Streptococcus zooepidemicus 균주 개량 및 발효조 배양공정 최적화)

  • Kim, Soo Yeon;Chun, Gie-Taek
    • Microbiology and Biotechnology Letters
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    • v.48 no.3
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    • pp.344-357
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    • 2020
  • Strain improvement and bioprocess development were undertaken to enhance hyaluronic acid(HA) production by Streptococcus zooepidemicus cells. Using a high-yielding mutant strain, statistical medium optimization was carried out in shake flask cultures, resulting in 52% increase in HA production (5.38 g/l) at the optimal medium composition relative to the parallel control cultures. For sufficient supply of dissolved oxygen (DO), which turned out to be crucial for enhanced production of HA, agitation system and speed were intensively investigated in 5 L bioreactor cultures. Increase in oxygen mass transfer coefficient (kLa) through increment of agitation speed (rpm) and 35% expansion of diameter of the newly-designed impellers showed significantly positive effects on HA production. By installing an expanded Rushton-turbine impeller for efficient break-down of sparged air, and an extended marine impeller above the Rushton-turbine impeller for efficient mixing of the air-born viscous fermentation broth, maximum amount of HA (9.79 g/l) was obtained at 450 rpm, 1.8 times higher level than that of the corresponding flask culture. Subsequently, the possibility of bioprocess scale-up to a 50 L bioreactor was investigated. Despite almost identical maximum HA production (9.11 vs 9.25 g/l), the average HA volumetric productivity (rp) of the 50 L culture turned out only 74% compared to the corresponding 5 L culture during the exponential phase, possibly caused by shear damages imposed on the producing cells at the high stirring in the 50 L culture. The scale-up process could be successfully achieved if a scale-up criterion of constant oxygen mass transfer coefficient (kLa) is applied to the 50 L pilot-scale bioreactor system.

Structural and optical properties of Ni-substituted spinel $LiMn_2O_4$ thin films (니켈 치환된 스피넬 LiMn2O4 박막의 구조적, 광학적 성질)

  • Lee, Jung-Han;Kim, Kwang-Joo
    • Journal of the Korean Vacuum Society
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    • v.15 no.5
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    • pp.527-533
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    • 2006
  • Spinel $LiNi_xMn_{2-x}O_4$ thin films were synthesized up to x = 0.9 by a sol-gel method employing spin-coating. The Ni-substituted films were found to maintain cubic structure at low x but to exhibit tetragonal structure for $x{\geq}0.6$. Such cubic-tetragonal phase transition indicates that $Ni^{3+}(d7)$ ions with low-spin $(t_{2g}^6,e_g^1)$ state occupy the octahedral sites of the compound, thus being subject to the Jahn-Teller distortion. By x-ray photoelectron spectroscopy both $Ni^{2+}$ and $Ni^{3+}$ ions were detected. Optical properties of the $LiNi_xMn_{2-x}O_4$ films were investigated by spectroscopic ellipsometry (SE) in the visible?ultraviolet range. The measured dielectric function spectra by SE mainly consist of broad absorption structures attributed to charge-transfer (CT) transitions, $O^{2-}(2p){\rightarrow}Mn^{4+}(3d)$ for 1.9 $(t_{2g})$ and $2.8{\sim}3.0$ eV $(e_g)$ structures and $O^{2-}(2p){\rightarrow}Mn^{3+}(3d)$ for 2.3 $(t_{2g})$ and $3.4{\sim}3.6$ eV $(e_g)$ structures. Also, sharp absorption structures were observed at about 1.6, 1.7, and 1.9 eV, interpreted as due to d-d crystal-field transitions within the octahedral $Mn^{3+}$ ion. The strengths of these absorption structures are reduced by the Ni substitution. Rapid reduction of the CT transition strength involving the eg states for x = 0.6 is attributed to the reduced wavefunction overlap between the $e_g$ and the $O^{2-}(2p)$ states due to the tetragonal extension of the lattice constant by the Jahn-Teller effect.

Preparationand Characterization of Rutile-anatase Hybrid TiO2 Thin Film by Hydrothermal Synthesis

  • Kwon, Soon Jin;Song, Hoon Sub;Im, Hyo Been;Nam, Jung Eun;Kang, Jin Kyu;Hwang, Taek Sung;Yi, Kwang Bok
    • Clean Technology
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    • v.20 no.3
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    • pp.306-313
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    • 2014
  • Nanoporous $TiO_2$ films are commonly used as working electrodes in dye-sensitized solar cells (DSSCs). So far, there have been attempts to synthesize films with various $TiO_2$ nanostructures to increase the power-conversion efficiency. In this work, vertically aligned rutile $TiO_2$ nanorods were grown on fluorinated tin oxide (FTO) glass by hydrothermal synthesis, followed by deposition of an anatase $TiO_2$ film. This new method of anatase $TiO_2$ growth avoided the use of a seed layer that is usually required in hydrothermal synthesis of $TiO_2$ electrodes. The dense anatase $TiO_2$ layer was designed to behave as the electron-generating layer, while the less dense rutile nanorods acted as electron-transfer pathwaysto the FTO glass. In order to facilitate the electron transfer, the rutile phase nanorods were treated with a $TiCl_4$ solution so that the nanorods were coated with the anatase $TiO_2$ film after heat treatment. Compared to the electrode consisting of only rutile $TiO_2$, the power-conversion efficiency of the rutile-anatase hybrid $TiO_2$ electrode was found to be much higher. The total thickness of the rutile-anatase hybrid $TiO_2$ structures were around $4.5-5.0{\mu}m$, and the highest power efficiency of the cell assembled with the structured $TiO_2$ electrode was around 3.94%.

Modeling on the Sorption Kinetics of Lead and Cadmium onto Natural Sediments (퇴적물에서의 납과 카드뮴의 흡착 동력학 모델링)

  • Kwak, Mun-Yong;Ko, Seok-Oh;Park, Jae-Woo;Jeong, Yeon-Gu;Shin, Won-Sik
    • Korean Journal of Ecology and Environment
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    • v.39 no.4 s.118
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    • pp.450-461
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    • 2006
  • In this study, sorption kinetics of lead (Pb) and cadmium (Cd) onto coastal sediments were investigated at pH 5.5 using laboratory batch adsorbers. Four different models: one-site mass transfer model (OSMTM), pseudo-first-order kinetic model (PFOKM) ,pseudo-second-order kinetic model (PSOKM) and two compartment first-order kinetic model (TCFOKM) were used to analyze the sorption kinetics. As expected from the number of model parameters involved, the three-parameter TCFOKM was better than the two-parameter OSMTM, PFOKM and PSOKM in describing sorption kinetics of Pb and Cd onto sediments. Most sorption of Pb and Cd was rapidly completed within the first three hours, followed by slow sorption in the subsequent period of sorption. All models predicted that the sorbed amount at the apparent sorption ($q_{e,s}$) equilibria increased as the CEC and surface area of the sediments increased, regardless of initial spiking concentration ($C_0$) and heavy metal and the sediment type. The sorption rate constant ($k_s,\;hr^{-1}$) in OSMTM also increased as the CEC and BET surface area increased. The rate constant of pseudo-first-order sorption ($k_{p1,s},\;hr^{-1}$) in PFOKM were not correlated with sediment characteristics. The results of PSOKM analysis showed that the rate constant of pseudo-second-order sorption ($k_{p2,s},\;g\;mmol^{-1}\;hr^{-1}$) and the initial sorption rate ($v_{o,s},\;mg\;g^{-1}\;hr^{-1}$) were not correlated with sediment characteristics. The fast sorption fraction ($f_{1,s}$) in TCFOKM increased as CEC and BET surface increased regardless of initial aqueous phase concentrations. The sorption rate constant of fast fraction ($k_{1,s}=10^{0.1}-10^{1.0}\;hr^{-1}$) was much greater than that of slow sorption fraction ($k_{2,s}=10^{-2}-10^{-4}\;hr^{-1}$) respectively.

GnRH Antagonist Versus Agonist Flare-up Protocol in Ovarian Stimulation of Poor Responder Patients (저 반응군의 체외수정시술을 위한 과배란유도에 있어 GnRH Antagonist 요법과 GnRH Agonist Flare Up 요법의 효용성에 관한 연구)

  • Ahn, Young-Sun;Yeun, Myung-Jin;Cho, Yun-Jin;Kim, Min-Ji;Kang, Inn-Soo;Koong, Mi-Kyoung;Kim, Jin-Yeong;Yang, Kwang-Moon;Park, Chan-Woo;Kim, Hye-Ok;Cha, Sun-Hwa;Song, In-Ok
    • Clinical and Experimental Reproductive Medicine
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    • v.34 no.2
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    • pp.125-131
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    • 2007
  • Objective: The aim of this study was to compare GnRH antagonist and agonist flare-up treatment in the management of poor responder patients. Methods: One hundred forty-four patients from Jan. 1, 2002 to Aug. 31, 2005 undergoing IVF/ICSI treatment who responded poorly to the previous cycle (No. of oocyte retrieved$\leq$5) and had high early follicular phase follicle stimulating hormone (FSH>12 mIU/ml were selected. Seventy-five patients received agonist flare-up protocol and 71 patients received antagonist protocol. We analyzed the number of oocytes retrieved, number of good embryos (GI, GI-1), total dose of hMG administered, implantation rate, cycle cancellation rate, pregnancy rate, live birth rate. Results: The cancellation rate was high in antagonist protocol (53.5% vs. 30.1%). The number of oocyte retrieved, the number of good embyos were high in agonist flare-up group. There was no statistical difference between GnRH agonist flare up protocol and GnRH antagonist protocol in implantation rate (14.5%, 10.1%), clinical pregnancy rate per transfer (29.4%, 21.2%) and live birth rate per transfer (21.6%, 18.2%). Although the result was not statistically significant, GnRH agonist flare up group showed a nearly doubled pregnancy rate and live birth rate per initial cycle than GnRH antagonist group. Conclusions: The agonist flare-up protocol appears to be slightly more effective than the GnRH antagonist protocol in implantation rate, pregnancy rate, live birth rate but shows statistically no significance. Agonist flare-up protocol improved the ovarian response in poor responders. However, based of the result of the study, we can expect improved ovarian response in poor responders by GnRH agonist flare up protocol.