• Title/Summary/Keyword: gels

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A study on the Preparation Methods of the Immobilized Encapsulation PVA-media for Wastewater Treatment (포괄고정화 PVA-gel의 물리적 특성 연구)

  • Lee, Eun-Woo;Chang, In-Soung;Chung, Son-Young;Nam, Byeong-Uk
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.6 no.2
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    • pp.116-121
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    • 2005
  • Immobilization technique by PVA encapsulation is an effective alternative for wastewater treatment. However little information is available about the effect of PVA characteristics on physical properties as an encapsulation media. This study aims at investigating the effect of the preparation methods of PVA and filler addition to media on the solubility of PVA. The solubility decreased as the freezing temperature decreased and the vacuum-drying was applied. Addition of the PAC (Powered Activated Carbon) and organoclay decreased the solubility of the PVA gels. Organoclay was more effective for lowering the solubility about 25% than the PAC. Nitrification with the PVA-coating media was less sufficient than with the polyurethane media due to the mass transfer restriction for oxygen and nutrients.

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Evaluation of Genetic Variability in Kenkatha Cattle by Microsatellite Markers

  • Pandey, A.K.;Sharma, Rekha;Singh, Yatender;Prakash, B.;Ahlawat, S.P.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.19 no.12
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    • pp.1685-1690
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    • 2006
  • Kenkatha cattle, a draft purpose breed, which can survive in a harsh environment on low quality forage, was explored genetically exploiting FAO-suggested microsatellite markers. The microsatellite genotypes were derived by means of the polymerase chain reaction (PCR) followed by electrophoretic separation in agarose gels. The PCR amplicons were visualized by silver staining. The allelic as well as genotypic frequencies, heterozygosities and gene diversity were estimated using standard techniques. A total of 125 alleles was distinguished by the 21 microsatellite markers investigated. All the microsatellites were highly polymorphic with mean allelic number of 5.95${\pm}$1.9 (ranging from 3-10 per locus). The observed heterozygosity in the population ranged between 0.250 and 0.826 with a mean of 0.540${\pm}$0.171, signifying considerable genetic variation. Bottleneck was examined assuming all three mutation models which showed that the population has not experienced bottleneck in recent past. The population displayed a heterozygote deficit of 21.4%. The study suggests that the breed needs to be conserved by providing purebred animals in the breeding tract.

A Quick Novel Method to Detect the Adulteration of Cow Milk in Goat Milk

  • Lee, Chi-Chei;Chang, His-Shan;Sheen, Hua-Shan
    • Asian-Australasian Journal of Animal Sciences
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    • v.17 no.3
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    • pp.420-422
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    • 2004
  • This study was to demonstrate a rapid novel method for detection of adulterated cow milk in goat milk using modified staining protocol after native polyacrylamide gel electrophoresis (PAGE). Samples of cow milk and goat milk containing 0, 0.5, 1.0 and 2.0% (v/v) of cow milk were analyzed. Low levels of cow milk mixed in goat milk were identified by the presence of higher mobility of $\beta$-lactoglobulin A ($\beta$-Lg A) in cow milk. By mini-gel electrophoresis, a distinguishable protein profile was visualized in 25 min using the modified Coomassie blue staining solution, in which methanol (50%) was replaced with ethanol (20%) and the concentrations of Coomassie blue and acetic acid were reduced from 2 to 0.13% and 10 to 5%, respectively. To visualize the milk proteins, gels in the staining solution were water-bathed in boiling water for 5 min and then cooled down immediately for 3-5 min. The sensitivity of this method is relatively high, allowing examination of 1% cow milk in goat milk. The procedure presented here is also very cost-effective due to less reagents needed. This simplified method would be useful and applicable to dairy industry for routine examination of goat milk.

Determination of Optimum Aggregates of Porcine Hepatocytes As a Cell Source of a Bioartificial Liver

  • Lee, Doo-Hoon;Lee, Ji-Hyun;Choi, Jeong-Eun;Kim, Young-Jin;Kim, Sung-Koo;Park, Jung-Keug
    • Journal of Microbiology and Biotechnology
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    • v.12 no.5
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    • pp.735-739
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    • 2002
  • Large quantities of porcine hepatocyte aggregates with various degrees of aggregation (DA) could be obtained by controlling the suspension periods (0,9,24, and 48 h), and by entrapping the hepatocyte aggregates in model materials of encapsulation such as Ca-alginate and type-I collagen gels. The effects of DA on liver-specific functions of hepatocytes were evaluated in order to obtain optimum DA for the cell source of bioartificial liver (BAL) systems. Irregular rugged aggregates (size $75 \pm 28$ $\mu\textrm{m}$) farmed by 24 h of suspension culturing showed peak viability and hepatic functions such as ammonia removal and albumin secretion in the two types of entrapment systems, thus offering themselves as a stable cell source of a BAL system for hepatic functions and scale-up.

Synthesis and Physical Properties of Hydrophilic Biomedical Polymers -Poly (N-substituted Acrylamide) and its Copolymer- (친수성 생의용 고분자의 합성 및 물성에 관한 연구)

  • 성용길;고대유
    • Journal of Biomedical Engineering Research
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    • v.9 no.1
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    • pp.47-60
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    • 1988
  • N-n-Propylacrylamide has been synthesized from acrylamide and n-propyl bromide. N -n Propylacrylamide was copolymerized with acrylamide at $60^{\circ}C$ in tetrahydrofuran using ${\alpha},{\alpha}'$-azobisisbutyronitrile as initiator. The synthesized monomer and copolymers have been identified by NMR and FT-lR spectrophotometer. The swelling properties of the crosslinked homopolymers were investigated at different temperatures. Three types of hydration layer around the back-bone structure of gels were determined. The thermal properties of copolymers were also measured by differential scanning calorimeter and thermogravimetry. As the amounts of N-n-propylacrylamide are increased, the enthalpic changes associated with endothermic transition and glass transition of the copolymers are decreased. As the amount of N-n-propylacrylamide is increased, the thermal stability is increased. The activation energies of thermal decomposition and dehydration for the poly (acrylamide-co-N -n-propylacrylamide) have been evaluated by Freeman and Carroll's method. As the amounts of N-n- propylacrylamide are increased, the activation energies of thermal decomposition and dehydration are increased.

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Hydrogel microrheology near the liquid-solid transition

  • Larsen, Travis;Schultz, Kelly;Furst, Eric M.
    • Korea-Australia Rheology Journal
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    • v.20 no.3
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    • pp.165-173
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    • 2008
  • Multiple particle tracking microrheology is used to characterize the viscoelastic properties of biomaterial and synthetic polymer gels near the liquid-solid transition. Probe particles are dispersed in the gel precursors, and their dynamics are measured as a function of the extent of reaction during gel formation. We interpret the dynamics using the generalized Stokes-Einstein relationship (GSER), using a form of the GSER that emphasizes the relationship between the probe particle mean-squared displacement and the material creep compliance. We show that long-standing concepts in gel bulk rheology are applicable to microrheological data, including time-cure superposition to identify the gel point and critical scaling exponents, and the power-law behavior of incipient network's viscoelastic response. These experiments provide valuable insight into the rheology, structure, and kinetics of gelling materials, and are especially powerful for studying the weak incipient networks of dilute gelators, as well as scarce materials, due to the small sample size requirements and rapid data acquisition.

Bacterial Multiplications and Electrophoretic Patterns of Soluble Proteins in Compatible and Incompatible Interactions of Pepper Leaves with Xanthomonas campestirs pv. vesicatoria (Xanthomonas campestris pv. vesicatoria에 감염된 고추잎의 친화적, 불친화적 반응에서 세균증식과 수용성 단백질의 전기영동 패턴)

  • 이연경;김영진;황병국
    • Korean Journal Plant Pathology
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    • v.10 no.4
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    • pp.305-313
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    • 1994
  • Typically susceptible lesions were developed on pepper (cv. Hanbyul) leaves inoculated with the compatible strains Ds 1 of Xanthomonas campestris pv. vesicatoria. The lesions appeared first water-soaked and then turned yellow with a chlorotic area. In contrast, the leaves inoculated with the incompatible strain 81-23 initially turned yellow and then developed local necrosis. Multiplication of x. c. pv. vesicatoria in pepper leaves also were distinctly different between the two strains. The strain Ds 1 multiplied more greatly than did the strain 81-23 in the infected leaves. X. c. pv. vesicatoria infection of pepper leaves induced the synthesis of soluble proteins, especially more greatly in the compatible than in the incompatible interactions. Some pathogenesis-related (PR) proteins were detected in the intercellular washing fluid (IWF) and extracts of the infected pepper leaves. In particular, the 32 kDa protein on SDS-PAGE gels appeared intensely in the incompatible interaction. In contrast, some proteins with moluecular masses of 65, 71, and 75 kDa disappeared in the infected pepper leaves. Isoelectric focusing could identify the pIs of soluble proteins in infected pepper leaves. The accumulation of the IWF from infected leaves was more conspicuous in the incompatible than the compatible interaction. These results suggest that some extremely acidic and basic proteins were induced and accumulated in the intercellular spaces of infected pepper leaves.

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Electrochemical Impedance Analysis of the Spin Coated V2O5 Xerogel (Spin Coated V2O5 Xerogel 박막 전극의 임피던스 특성 연구)

  • Park, Heai-Ku
    • Applied Chemistry for Engineering
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    • v.10 no.3
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    • pp.382-387
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    • 1999
  • The processes and the kinetics of the lithium intercalation into the spin coated $V_2O_5$ xerogel prepared by the sol-gel processing have been studied employing impedance analyzer. Homogeneous and quasi-isotropic thin films of the xerogel can be obtained as a result of random distribution of the $V_2O_5$ gels on the substrate by the use of the spin coating. Effective diffusion coefficient and charge transfer resistance vary more than one order of magnitude at high and low lithium composition in $V_2O_5$ xerogel, respectively.

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Two-Dimensional Electrophoretic Analysis of Rice Seed Proteins (쌀 종자 단백질의 2차원 전기영동적 분석)

  • Yoon, Hye-Hyun;Kim, Seung-Ho
    • Applied Biological Chemistry
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    • v.32 no.2
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    • pp.85-90
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    • 1989
  • High resolution two-dimensional (2-D) electrophoresis with isoelectrofocusing in the first dimension and electrophoresis in sodium dodecyl sulfate in acrylamide gradient gels in the second dimension has been used to produce maps of proteins, extracted from rice seeds with 2% sodium dodecyl sulfate/5% 2-mercaptoethanol. Six rice cultivars-three Japonica types and three Tongil(high-yielding) types-at six maturities were studied. Composite map was constructed and more than 300 polypeptide spots were counted in the pH range of $5.2{\sim}8.3$ and molecular range of $20,000{\sim}100,000$. Vast differences were observed between varieties and between maturities in the maps.

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The Clinical Implications of Poly Implant Proth$\grave{e}$se Breast Implants: An Overview

  • Wazir, Umar;Kasem, Abdul;Mokbel, Kefah
    • Archives of Plastic Surgery
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    • v.42 no.1
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    • pp.4-10
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    • 2015
  • Mammary implants marketed by Poly Implant Proth$\grave{e}$se (PIP) were found to contain industrial grade silicone and this caused heightened anxiety and extensive publicity regarding their safety in humans. These implants were used in a large number of patients worldwide for augmentation or breast reconstruction. We reviewed articles identified by searches of Medline, PubMed, Embase, and Google Scholar databases up to May 2014 using the terms: "PIP", "Poly Implant Proth$\grave{e}$se", "breast implants" and "augmentation mammoplasty" "siloxanes" or "silicone". In addition the websites of regulating bodies in Europe, USA, and Australia were searched for reports related to PIP mammary implants. PIP mammary implants are more likely to rupture than other implants and can cause adverse effects in the short to the medium term related to the symptoms of rupture such as pain, lumps in the breast and axilla and anxiety. Based on peer-reviewed published studies we have calculated an overall rupture rate of 14.5% (383/2,635) for PIP implants. However, there is no evidence that PIP implant rupture causes long-term adverse health effects in humans so far. Silicone lymphadenopathy represents a foreign body reaction and should be treated conservatively. The long-term adverse effects usually arise from inappropriate extensive surgery, such as axillary lymph node dissection or extensive resection of breast tissue due to silicone leakage.