• Title/Summary/Keyword: Separation membrane

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Studies on Selective Separation of Highly Motile Bovine Sperm (고활력우정자(高活力牛精子)의 선택적(選擇的) 분리(分離)에 관한 연구(硏究))

  • Kim, Myung-cheol
    • Korean Journal of Veterinary Research
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    • v.24 no.2
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    • pp.245-266
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    • 1984
  • As a fundamental study to increase the reproductive efficiency in cattle, highly motile sperm were separated and collected from raw semen, extended semen and frozen semen by different methods using various concentrations of bovine serum albumin or Tyrode's solution. Various characteristics and light microscopic and electron-microscopic morphology of sperm separated by different methods were compared. The results obtained were as follows; 1. The sperm separated from raw semen using bovine serum albumin showed significantly high value in motility, motile sperm count, percent of normal sperm and progressive motility, as compared with control sperm and revealed the highest sperm recovery rate when separated with 6% bovine serum albumin. 2. The sperm motility, percent of normal sperm and progressive motility of the highly motile sperm frozen after being separated from raw semen with bovine serum albumin, showed significantly high value than those of a control sperm and especially found the highest value when separated with 20% bovine serum albumin. 3. Light-microscopic percent of abnormality was significantly low in the prefrozen and postfrozen highly motile sperm separated with bovine serum albumin, as compared with control sperm. 4. Electron-microscopic finding of the highly motile sperm separated with bovine serum albumin showed low percent of deformity in the dilatation and vesiculation of cell membrane, in dilatation and density loss of acrosome than in those of control sperm. 5. It was impossible to separate the highly motile sperm from frozen semen with bovine serum albumin, but it was possible with Tyrode's solution. 6. Recovery rate of highly motile sperm from raw semen extended semen and frozen semen was the highest when the sperm pellet stood in Tyrde's solution for 80 minutes. 7. The highly motile sperm separated from raw semen, extended semen and frozen semen with Tyrode's solution showed significantly high value in motility, progressive motility and percent of normal sperm, as compared with control sperm. 8. Highly motile sperm, when separated from raw semen, extended semen and frozen semen with Tyrode's solution, showed significantly low percent of microscopic abnormality as compared with control sperm.

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Recovery of Pd(II), Pt(IV), and Rh(III) Using Polyelectrolytes

  • Lee, You-Sean;Lee, Hoosung;Chung, Koo-Soon
    • Analytical Science and Technology
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    • v.8 no.4
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    • pp.561-568
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    • 1995
  • Two methods, precipitation and ultrafiltration, were applied in order to recover platinum group metals(PGM) by complexing them with water-soluble polyelectrolytes, e.g., polyethyleneimine [PEl], poly(2-vinylpyridine) [2-PVP], poly (4-vinylpyridine) [4-PVP], and poly (styrene sulfonic acid) [PSSA]. In the precipitation method, the PGM-polyelectrolyte complex that was formed by mixing first with polybase, e.g.,4-PVP at pH 1 was precipitated by further mixing with polyacid, e.g., PSSA. However, the recovery of PGM obtained by this method was not quantitative(less than 70%). The "sandwiching" binding between the metal anions and two polyelectrolytes was examined by X-ray photoelectron spectroscopy(XPS). The XPS studies indicated that the PGM atom was bound with the acdic and basic polyelectrolyte via its oxygen and nitrogen atom, respectively. The recovery of PGM using polyelectrolyte was further studied by ultrafiltration methods as follows : The PGM ions, eomplexed at pH 1 with polyelectrolyte, allowed the applicntion of membrane filtration by virtue of the great differences in molecular weights between PGM and other low molecular weight species. By applying this method, Pd and Pt (ca. $10^{-4}M$) were selectively separated almost quantitatively from coexisting metal ions, e.g., $Cu^{2+}$ and $Ni^{2+}$. The EPR spectra and viscosity measurements indicated that these polyelectrlytes were not bound to $Cu^{2+}$ and $Ni^{2+}$ ions at this pH, which provided the basis for selective separation of PGM(Pd, Pt and Rh) from these coexisting ions.

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Comparison of Cell Lysis Techniques via Q-TOF LC/MS

  • Kaplan, Ozan;Oncul, Selin;Ercan, Ayse;Celebier, Mustafa
    • Mass Spectrometry Letters
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    • v.11 no.2
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    • pp.36-40
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    • 2020
  • Untargeted metabolomics is a useful tool for drug development focusing on novel chemotherapeutic and chemopreventative agents against cancer cells. In recent years, quadrupole time of flight liquid chromatography-mass spectrometry (Q-TOF LC/MS)-based untargeted metabolomic approaches have gained importance to evaluate the effect of these agents at the molecular level. The researchers working on cell culture studies still do not apply standardized methodologies on sample preparation for untargeted metabolomics approaches. In this study, the rough and wet lysis techniques performed on MCF-7 breast cancer cells were compared with each other via the Q-TOF LC/MS-based metabolomic approach. The C18 and hydrophilic interaction liquid chromatography (HILIC) columns were used for the separation of the metabolites in MCF-7 cell lysates. 505 peaks were detected through the HILIC column and 551 peaks were found through the C18 column for the wet lysis technique. This situation supported by the base peak chromatograms showed that the wet lysis technique allowed us to extract higher number of non-polar metabolites. Almost equal number of metabolites was found for the C18 and HILIC columns (697 peaks for the HILIC column and 695 peaks for the C18 column) when the rough lysis technique was used. However, the intensities of polar metabolites were higher for the rough lysis technique on base peak chromatograms for both the HILIC and C18 columns. Although cell lysis technique, which is the first step in the sample preparation for cell culture studies, does not cause dramatic differences in the number of the detected metabolite peaks, it affects the polar and non-polar metabolite ratio significantly. Therefore, it must be considered carefully especially for in vitro drug development studies.

Biological Fixation of $CO_2$ by Chlorella sp. HA-1 in a Semi-Continuous and Series Reactor System

  • LEE JAE-YOUNG;KWON TAE-SOON;BAEK KITAE;YANG JI-WON
    • Journal of Microbiology and Biotechnology
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    • v.15 no.3
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    • pp.461-465
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    • 2005
  • Characteristics of biological $CO_2$ fixation by Chlorella sp. HA-1 were investigated in a semi-continuous and series reactor system using an internally illuminated photobioreactor to overcome shortcomings of physicochemical technologies such as adsorption and membrane separation. High $CO_2$ fixation rate was achieved in the semi-continuous reactor system, in which the dilution ratios of the culture medium were controlled. The average $CO_2$ fixation rate was maintained almost constantly when the dilution ratio increased by 0.1 increment from the initial value of 0.5. The total removal efficiency of $CO_2$ was enhanced by employing a series reactor system. The average $CO_2$ fixation rate increased until 4.013 g $CO_2\;day^{-1}$ in a series operation of four reactors, compared to 0.986 g $CO_2\;day^{-1}$ in a batch operation mode. The total $CO_2$ fixation rate was proportional to the number of reactors used in the series reactor system. In the series reactor system of semi-continuous operation, a large amount of $CO_2$ was removed continuously for 30 days. These results showed that the present reactor systems are efficient and economically feasible for a biological $CO_2$ fixation.

Preparation and Characterization of (La, Sr)$MnO_3$ Electrode for High Temperature Steam Electrolysis by Glycine-Nitrate Process (Glycine-Nitrate Process를 이용한 고온 수증기 전해용 (La, Sr)$MnO_3$ 전극의 합성 및 특성 연구)

  • Choi, Ho-Sang;Kim, Hyun-Jin;Ryu, Si-Ok;Hwang, Gab-Jin
    • Transactions of the Korean hydrogen and new energy society
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    • v.18 no.1
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    • pp.46-51
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    • 2007
  • LSM powder material for an oxygen-electrode(anode) of High Temperature Steam Electrolysis (RISE) was synthesized by a Modified-Glycine nitrate process(GNP). Amount of nitric acid and its concentration was varied to find out an appropriate composition for the oxygen-electrode(anode). In order to optimize the amount of Glycine used as an oxidant of self-combustion process, the ratio of Glycine to Anion was varied. $La_{0.8}Sr_{0.2}MnO_3$, $La_{0.5}Sr_{0.5}MnO_3$, and $La_{0.2}Sr_{0.8}MnO_3$ were synthesized in this study. Those LSM were dried for overnight to remove moisture from the material at $110^{\circ}C$ and were calcined 2 hours at $650^{\circ}C$ and were sintered in a furnace for 5 hours at $1400^{\circ}C$. Their structures, surface morphologies, surface areas, and weight changes were investigated with XRD, SEM, BET, and TG/DTA. The best perovskite phase for the oxygen-electrode of HTSE was obtained with $La_{0.8}Sr_{0.2}MnO_3$ formula in which 100 ml of 3M nitric acid was used in the preparation of its formula. The optimized ratio of Glycine to Anion was 2.

Protein Carboxyl Ο-Methylation in Porcine Liver and Testis (돼지 간 및 정소에서 단백질 카르복실메칠화 현상)

  • 조재열;김성수;이향우;홍성렬
    • YAKHAK HOEJI
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    • v.45 no.1
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    • pp.46-54
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    • 2001
  • Protein carboxyl Ο-methylation is a kind of enzymatic reaction producing carboxyl methylester catalyzed by protein carboxyl Ο-methyltransferases at the carboxyl group of amino acid residues in polypeptide. Since the finding of carboxyl methylesterl many studies have been focused on the under-standing of biological functions in eukaryotes but still not clear except for roles in Ras attachment to membrane and protein repair. In this study, we investigated the protein carboxyl methylation in porcine liver and testis in respect of identification and characterization of carboxyl methylesters and natural proteinous substrates using pH stability of the esters and electrophoresis under acidic and basic conditions. We detected several kinds of methyl esters, 3 kinds each in cytosolic fractions from liver and testis. Under the treatment of strong acid and base, the ratio between base-stable substrates and unstable ones in liver (4 : 6) was different from the ratio obtained in testis (6 : 4). The methyl accepting capacities were affected by enzymatic proteolysis between the range of 55 to 65% in liver and of 35 to 45% in testis. Separation of the methylated proteins by acidic electrophoresis in the presence of urea and SDS revealed distinctively natural substrates of 26, 33 and 80 kD in the cytosol from liver and of 14, 25, 32 and 86 kD from testis. Most of the labelling, however were lost following electrophoresis under moderate alkaline condition, except for molecules of newly detected 7 and 17 kD in livers and 15, 29, 40 and 80 kD in testis. From these results, it was proposed that protein carboxyl Ο-methylation in each organs may be catalyzed by different classes of protein carboxyl Ο-methyltransferases. In addition, it is suggested that the protein carboxyl methylation in liver and testis may have different patterns in respect of natural substrates.

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Effects of pH and slow mixing conditions on heavy metal hydroxide precipitation (pH와 완속교반 조건에 따른 중금속 수산화물 화학침전 특성)

  • Park, Jong-Hun;Choi, Gyu-Jin;Kim, Sang-Hyoun
    • Journal of the Korea Organic Resources Recycling Association
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    • v.22 no.2
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    • pp.50-56
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    • 2014
  • Conventional coagulation-gravity settling processes in heavy metal removal have a problem in coagulant cost and instability of the settling efficiency. The authors investigated the effects of pH and slow mixing conditions on heavy metal hydroxide precipitation and the particle size distribution of the precipitate for a precipitation-membrane separation process. The optimum pH values for the hydroxide precipitation ranged from 9 to 10. The addition of $FeCl_3$ did not enhance the heavy metal removal. 20 min of slow mixing at 70 rpm showed the maximum heavy metal removal to meet the water quality criteria for effluent discharge. More than 99.9% of the heavy metal precipitate particles were bigger than $2{\mu}m$.

The Heavy Metal Tolerant Soil Bacterium Achromobacter sp. AO22 Contains a Unique Copper Homeostasis Locus and Two mer Operons

  • Ng, Shee Ping;Palombo, Enzo A.;Bhave, Mrinal
    • Journal of Microbiology and Biotechnology
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    • v.22 no.6
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    • pp.742-753
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    • 2012
  • Copper-containing compounds are introduced into the environment through agricultural chemicals, mining, and metal industries and cause severe detrimental effects on ecosystems. Certain microorganisms exposed to these stressors exhibit molecular mechanisms to maintain intracellular copper homeostasis and avoid toxicity. We have previously reported that the soil bacterial isolate Achromobacter sp. AO22 is multi-heavy metal tolerant and exhibits a mer operon associated with a Tn21 type transposon. The present study reports that AO22 also hosts a unique cop locus encoding copper homeostasis determinants. The putative cop genes were amplified from the strain AO22 using degenerate primers based on reported cop and pco sequences, and a constructed 10,552 base pair contig (GenBank Accession No. GU929214). BLAST analyses of the sequence revealed a unique cop locus of 10 complete open reading frames, designated copSRABGOFCDK, with unusual separation of copCD from copAB. The promoter areas exhibit two putative cop boxes, and copRS appear to be transcribed divergently from other genes. The putative protein CopA may be a copper oxidase involved in export to the periplasm, CopB is likely extracytoplasmic, CopC may be periplasmic, CopD is cytoplasmic/inner membrane, CopF is a P-type ATPase, and CopG, CopO, and CopK are likely copper chaperones. CopA, B, C, and D exhibit several potential copper ligands and CopS and CopR exhibit features of two-component regulatory systems. Sequences flanking indicate the AO22 cop locus may be present within a genomic island. Achromobacter sp. strain AO22 is thus an ideal candidate for understanding copper homeostasis mechanisms and exploiting them for copper biosensor or biosorption systems.

Late-term healing in an augmented sinus with different ratios of biphasic calcium phosphate: a pilot study using a rabbit sinus model

  • Lim, Hyun-Chang;Hong, Ji-Youn;Lee, Jung-Seok;Jung, Ui-Won;Choi, Seong-Ho
    • Journal of Periodontal and Implant Science
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    • v.46 no.1
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    • pp.57-69
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    • 2016
  • Purpose: The aim of this pilot study was to determine the osteoconductivity and dimensional stability of augmented sinuses using different ratios of biphasic calcium phosphate (BCP) in a rabbit sinus model. Methods: Each sinus of New Zealand white rabbits (2.5-3.5 kg) was assigned to one of two groups: BCP with a hydroxyapatite to ${\beta}$-tricalcium phosphate (HA:${\beta}$-TCP) ratio of 70:30 (group TCP30) and BCP with an HA:${\beta}$-TCP ratio of 30:70 (group TCP70). After preparing a window in the antral wall of a sinus, the Schneiderian membrane was elevated, and the applicable material was grafted. A fluorochrome calcein green was injected five days before euthanizing the animals at four months post-surgery. The specimens were analyzed histologically, histomorphometrically, and by using micro-computed tomography (micro-CT). Results: Micro-CT analysis revealed that the total augmented volume and the new bone volume did not differ significantly between the two groups whereas the resorption of materials was greater in the TCP70 group. The trabecular thickness, number, and separation also did not differ significantly between the two groups. Histomorphometrically, the areas of total augmentation, new bone, and residual material, as well as the ratio of new-bone-material contact did not differ significantly between the groups. Histologically, the residual particles were more scattered in the TCP70 group than in the TCP30 group. The fluorescence of the calcein green did not differ notably between the two groups. Conclusions: The osteoconductivity and dimensional stability of the two BCPs with different ratios tested in this study were comparable after four months of healing. Therefore, we conclude that both BCPs show promise as a bone substitute for sinus augmentation.

Evaluation of Wind-Induced Vibration for Multiple Stacks Using Numerical Analysis (전산 해석을 이용한 다중연돌의 유체유발진동)

  • Yang, Kwangheok;Park, Chaegwan;Kim, Hyeonjoon;Baek, Songyoul;Park, Soontae
    • Plant Journal
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    • v.12 no.3
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    • pp.24-31
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    • 2016
  • Wind-induced vibration is a phenomenon that a struture is oscillated due to wind force such as buffeting, vortex shedding wake and etc., which is one of important characteristics to be considered for design in case that stack has significant slenderness ratio or low natural frequency. International design standards of stack define several criteria for evaluating the suitability of stack design, which describe the required design considerations for each range of design parameters and provide the instruction to verify the stack design against wind-induced vibration simply. However, there is a limitation that they cannot provide quantitative information in case code requirement cannot be satisfied due to constraints of plant space or economical design. In order to overcome the limiation of code, integrated numerical analysis of computational fluid dynamics, harmonic analysis and finite element analysis were proposed to investigate wind-induced vibration for multiple stacks in actual plant. Simulated results of mutual wake interference effect between adjacent stacks were evaluated and compared to the criteria in international standards.

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