• Title/Summary/Keyword: Micro-cell

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In-situ Phase Transition Study of Minerals using Micro-focusing Rotating-anode X-ray and 2-Dimensional Area Detector (집속 회전형 X-선원과 이차원 검출기를 이용한 광물의 실시간 상전이 연구)

  • Seoung, Dong-Hoon;Lee, Yong-Moon;Lee, Yong-Jae
    • Economic and Environmental Geology
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    • v.45 no.2
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    • pp.79-88
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    • 2012
  • The increased brightness and focused X-ray beams now available from laboratory X-ray sources facilitates a variety of powder diffraction experiments not practical using conventional in-house sources. Furthermore, the increased availability of 2-dimensional area detectors, along with implementation of improved software and customized sample environmental cells, makes possible new classes of in-situ and time-resolved diffraction experiments. These include phase transitions under variable pressure- and temperature conditions and ion-exchange reactions. Examples of in-situ and time-resolved studies which are presented here include: (1) time-resolved data to evaluate the kinetics and mechanism of ion exchange in mineral natrolite; (2) in-situ dehydration and thermal expansion behaviors of ion-exchanged natrolite; and (3) observations of the phases forming under controlled hydrostatic pressure conditions in ion-exchanged natrolite. Both the quantity and quality of the in-situ diffraction data are such to allow evaluation of the reaction pathway and Rietveld analysis on selected dataset. These laboratory-based in-situ studies will increase the predictability of the follow-up experiments at more specialized beamlines at the synchrotron.

Electrochemical Characteristics of Zn and Si Ion-doped HA Films on Ti-6Al-4V by PEO Treatment

  • Lim, Sang-Gyu;Hwang, In-Jo;Choe, Han-Cheol
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2016.11a
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    • pp.199-199
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    • 2016
  • Commercially pure titanium (cp-Ti) and Ti alloys (typically Ti-6Al-4V) display excellent corrosion resistance and biocompatibility. Although the chemical composition and topography are considered important, the mechanical properties of the material and the loading conditions in the host have, conventionally. Ti and its alloys are not bioactive. Therefore, they do not chemically bond to the bone, whereas they physically bond with bone tissue. The electrochemical deposition process provides an effective surface for biocompatibility because large surface area can be served to cell proliferation. Electrochemical deposition method is an attractive technique for the deposition of hydroxyapatite (HAp). However, the adhesions of these coatings to the Ti surface needs to be improved for clinical used. Plasma electrolyte oxidation (PEO) enables control in the chemical com position, porous structure, and thickness of the $TiO_2$ layer on Ti surface. In addition, previous studies h ave concluded that the presence of $Ca^{+2}$ and ${PO_4}^{3-}$ ion coating on porous $TiO_2$ surface induced adhesion strength between HAp and Ti surface during electrochemical deposition. Silicon (Si) in particular has been found to be essential for normal bone and cartilage growth and development. Zinc (Zn) plays very important roles in bone formation and immune system regulation, and is also the most abundant trace element in bone. The objective of this work was to study electrochemical characteristcs of Zn and Si coating on Ti-6Al-4V by PEO treatment. The coating process involves two steps: 1) formation of porous $TiO_2$ on Ti-6Al-4V at high potential. A pulsed DC power supply was employed. 2) Electrochemical tests were carried out using potentiodynamic and AC impedance methoeds. The morphology, the chemical composition, and the micro-structure an alysis of the sample were examined using FE-SEM, EDS, and XRD. The enhancements of the HAp forming ability arise from $Si/Zn-TiO_2$ surface, which has formed the reduction of the Si/Zn ions. The promising results successfully demonstrate the immense potential of $Si/Zn-TiO_2$ coatings in dental and biomaterials applications.

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Versatility of Radial Forearm Free Flap on Head and Neck Cancer in Old-Aged Patient and its Donor Site Morbidity (노인 두경부 종양환자에서 노쪽아래팔유리피판술의 유용성 및 공여부 결과의 비교)

  • Lee, Ki-Eung;Koh, Sung-Hoon;Eo, Su-Rak
    • Archives of Reconstructive Microsurgery
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    • v.15 no.2
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    • pp.92-100
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    • 2006
  • Radial forearm free flap (RFFF) has been established itself as a versatile and widely used method for reconstruction of the head and neck, although it is still criticized for high mortality of donor site. Delayed wound healing, cosmetic deformity, vascular compromise and potentially reduced wrist function have many plastic surgeons hesitate to adapt it as a first choice in micro-reconstruction. To overcome these drawbacks, some techniques for donor-site repair such as V-Y advancement with full thickness skin graft (FTSG), application of artificial dermis ($Terudermis^{(R)}$) or acellular dermal matrix ($AlloDerm^{(R)}$), and double-opposing rhomboid transposition flap have been reported. Authors performed 4 cases of RFFF in old-aged patients of the head and neck cancer from April 2005 to February 2006. We compared the outcomes of donor site of RFFF which were resurfaced with split thickness skin graft (STSG) only and STSG overlying an $AlloDerm^{(R)}$. Patients were all males ranging from 59 to 74 years old (mean, 67.5). Three of them had tongue cancers, and the other showed hypopharyngeal cancer. All cases were pathologically confirmed as squamous cell carcinomas. We included the deep fascia into the flap, so called subfascially elevated RFFF in three cases, and in the other one, we dissected the RFFF suprafascially leaving the fascia intact. The donor site of the suprafascially elevated RFFF was resurfaced with STSG only. Among three of subfascially elevated RFFFs, donor-sites were covered with thin STSG only in one case, and STSG overlying $AlloDerm^{(R)}$ in two cases. All RFFFs were survived completely without any complication. The donor site of the suprafascially elevated RFFF was taken well with STSG only. But, the partial graft loss exposing brachioradialis and flexor carpi radialis muscle was unavoidable in all the subfascially elevated RFFFs irregardless of $AlloDerm^{(R)}$ application. Considering that many patients of the head and neck cancer are in old ages, we believe the RFFF is still a useful and versatile choice for resurfacing the head and neck region after cancer ablation. Its reliability and functional characteristics could override its criticism for donor site in old-aged cancer patients.

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Expression of Hepatitis B Virus S Gene in Pichia pastoris and Application of the Product for Detection of Anti-HBs Antibody

  • Hu, Bo;Liang, Minjian;Hong, Guoqiang;Li, Zhaoxia;Zhu, Zhenyu;Li, Lin
    • BMB Reports
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    • v.38 no.6
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    • pp.683-689
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    • 2005
  • Antibody to hepatitis B surface antigen (HBsAb) is the important serological marker of the hepatitis B virus (HBV) infection. Conventionally, the hepatitis B surface antigen (HBsAg) obtained from the plasma of HBV carriers is used as the diagnostic antigen for detection of HBsAb. This blood-origin antigen has some disadvantages involved in high cost, over-elaborate preparation, risk of infection, et al. In an attempt to explore the suitable recombinant HBsAg for the diagnostic purpose, the HBV S gene was expressed in Pichia pastoris and the product was applied for detection of HBsAb. Hepatitis B virus S gene was inserted into the yeast vector and the expressed product was analyzed by sodium dodecyl sulphate polyacrolamide gel electrophoresis (SDS-PAGE), immunoblot, electronic microscope and enzyme linked immunosorbent assay (ELISA). The preparations of synthesized S protein were applied to detect HBsAb by sandwich ELISA. The S gene encoding the 226 amino acid of HBsAg carrying ahexa-histidine tag at C terminus was successfully expressed in Pichia pastoris. The His-Tagged S protein in this strain was expressed at a level of about 14.5% of total cell protein. Immunoblot showed the recombinant HBsAg recognized by monoclonal HBsAb and there was no cross reaction between all proteins from the host and normal sera. HBsAb detection indicated that the sensitivity reached 10 mIu (micro international unit)/ml and the specificity was 100% with HBsAb standard of National Center for Clinical Laboratories. A total of 293 random sera were assayed using recombinant S protein and a commercial HBsAb ELISA kit (produced by blood-origin HBsAg), 35 HBsAb positive sera and 258 HBsAb negative sera were examined. The same results were obtained with two different reagents and there was no significant difference in the value of S/CO between the two reagents. The recombinant HBV S protein with good immunoreactivity and specificity was successfully expressed in Pichia pastoris. The reagent for HBsAb detection prepared by Pichia pastoris-derived S protein showed high sensitivity and specificity for detection of HBsAb standard. And a good correlation was obtained between the reagent produced by recombinant S protein and commercial kit produced by blood-origin HBsAg in random samples.

Regeneration of symmetric protoplast fusion between cabbage (Brassica oleracea L.) and radish (Raphanus sativus L.) (양배추와 무의 동형 원형질체 융합을 이용한 식물체의 재분화)

  • In, Dong-Su;Song, Min-Jung;Jang, In-Chang;Min, Byung-Whan;Nahm, Seok-Hyeon;Shin, Jong-Sub;Lee, See-Woo;Harn, Chee-Hark
    • Journal of Plant Biotechnology
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    • v.35 no.2
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    • pp.121-126
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    • 2008
  • Protoplasts from cabbage and radish were isolated and fused symmetrically by PEG treatment. The PEG treated mixture of high concentrated protoplasts produced lots of micro-calli after $2{\sim}3$ weeks. The microcalli developed to normal calli and shoots were regenerated from the calli. A total of 218 shoots were regenerated, but none of them contained the NWB-CMS specific DNA marker, indicating that the transfer of the radish NWB-CMS character into cabbage did not occur. However, ISSR analysis revealed that the cell fusion between protoplasts from radish and cabbage was occurred (3 out of 208 plantlet). The fused regenerants possessed the characteristics of source plants used for protoplast fusion. After vernalization, three regenerants were flowered with white petal color as seen in radish. Only three seeds were able to obtain from one regenerant by backcrossing with the cabbage pollen.

Serum Mineral and Haematobiochemical Profile of Microfilariae Infected Cattle in India: Its Effects on Production and Therapy

  • Sharma, M.C.;Joshi, Chinmay
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.3
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    • pp.357-365
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    • 2002
  • A survey was under taken of six district of Northern India viz. Bareilly, Pilibhit, Udham Singh Nagar, Nainital, Almora and Rampur. The age, breed, sex and physiological status recorded. A total number of 854 cattle examined out of which lactating (274 cases), non lactating (302 cases) heifers (128 cases), calves (82 cases) and adult male (68 cases) were examined. An incidence of 4.92 percent (42) of microfilarisis was recorded. The highest prevalence was observed in Rudrapur District of Udham Singh Nagar (33.33%, 4/12), followed by Lalkaun in Nanital District (21.74%, 10/46), Rampur (12.50%, 2/16), Bareilly (8.16%, 8/98) and Pilibhit (1.22%, 1/82). No infection was observed in Almora region. Amongst 854 cattle of different group incidence was highest in adult male (12.20%, 10/82), followed by non lactating (3.82%, 12/314) and lactating (2.70%, 2/74), (7.64%, 12/157) was found in Heifers. For haemeto-biochemical, serum minerals estimations and therapeutic study 32 animals suffering from filariasis and 18 healthy animals were taken. 16 animals were treated with ivermectin $@200{\mu}g/kg $ body weight. Effect of this disease on production has also been estimated for which body weight and milk production was observed. The main clinical manifestations observed were anaemia, loss of appetite, debility, oedematous swelling especially in the abdominal region, increased heart rate, and respiration rate. Haematological changes indicated decrease in hemoglobin, total erythrocyte count, packed cell volume, erthrocyte fragility and neutrophil, whereas there was significant increase in erythrocytes sedimentation rate (ESR), total leukocyte count (TLC), lymphocyte and eosinophils. Biochemical changes showed significant reduction in the values of serum albumin, A : G ratio, where as there was significant increase in blood glucose, blood urea nitrogen (BUN), globulin, total lipid, total cholesterol, phospholipids, serum bilirubin. Serum mineral profile also altered markedly, which indicate a significant decrease in Ca, Cu, Fe, Zn, and Mn with increase value of Na and Cl. There was no significant change in P and K values. Enzyme pattern in micro filaria infected animal indicated increased level of AST, ALT, alkaline phosphatase, ornithine carbamyl transferase, sorbitol dehydrogenase, glutamate dehydrogenase, isocitric dehydrogenase and lactate dehydrogenase. In blood gas values and acid/base balance, there was an increase in $PVCo_2$ and $PVo_2$. It has been observed that microfilaria infected cattle showed decrease in body weight and milk production. Animal treated with ivermectin showed the return of these above values toward normalcy.

Different Sources and Levels of Copper Supplementation on Performance and Nutrient Utilization of Castrated Black Bengal (Capra hircus) Kids Diet

  • Mondal, M.K.;Biswas, P.
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.7
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    • pp.1067-1075
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    • 2007
  • Twenty eight 3-4 month old castrated Black Bengal kids (Capra hircus) were used to determine the effects of source and level of dietary copper (Cu) concentration on their performance and nutrient utilization. Cu was supplemented (0, 10, 20 and 30 mg/kg diet DM) as copper sulfate ($CuSO_4$, $5H_2O$) or copper proteinate (Cu-P). Kids were fed a basal diet containing maize (19.5%), soybean (17.0%), deoiled rice bran (56.5%), molasses (4.0%), di-calcium phosphate and salt (1.0% each) and mineral and vitamin mixture (0.5% each) supplements at 3.5% of body weight to meet NRC (1981) requirements for protein, energy, macro minerals and micro minerals, excluding Cu. The basal diet contained 5.7 mg Cu/kg, 122.5 mg Fe/kg, 110 mg Zn/kg, 0.26 mg Mo/kg and 0.32% S. $CuSO_4$ or Cu-P was added to the basal diet at the rate of 10, 20 and 30 mg/kg. Kids were housed in a well ventilated shed with facilities for individual feeding in aluminum plated metabolic cages. Blood samples were collected from the jugular vein on d 0, 30, 60 and 90 to determine hemoglobin (Hb), packed cell volume (PCV), total erythrocyte count (TEC), total leukocyte count (TLC) and serum enzymes (alkaline phosphatase, alanine transferase and aspertate transferase). A metabolism trial of 6 days duration was conducted after 90 days of experimental feeding. Statistical analysis revealed that source and level of Cu supplementation improved live weight gain (p<0.04) and average daily gain (p<0.01). No significant contribution of source and level of Cu to alter serum serum enzymes was evident. Goats fed Cu-P tended to have higher Hb, PCV and TEC than with $CuSO_4$ supplementation. Cu-P increased digestibility of ether extract (EE, p<0.02) and crude fiber (p<0.05) and showed an increasing trend (p<0.09) for digested crude protein (CP) and crude fiber (CF). Supplemental dose of Cu linearly improved (p<0.02) digestibilities of dry matter (DM), organic matter (OM), EE and nitrogen free extract (NFE). Though the absorption of nitrogen (N) was not affected (p>0.10) by both source and dose of Cu, N retention was affected (p<0.04) and there was a significant $Source{\times}Dose$ interaction (p<0.05). Final body weight (BW) was not influenced (p>0.10) by the source of Cu but increasing dose of Cu increased (p<0.04) the BW of kids. TDN intake (g/kg $W^{0.75}$) was higher (p<0.05) with the increased dose of Cu and there was a significant $Source{\times}Dose$ interaction. It was concluded that supplementation of Cu from different sources and varying dose level in a concentrate based diet may improve performance, nutrient utilization and plane of nutrition in castrated Black Bengal kids. The effects on performance and nutrient utilization are more pronounced with Cu-P than $CuSO_4$ supplementation. Higher dose of Cu showed better result than lower dose.

A Study on the Fluorescence Characteristics of Dye-doped Silica Nanoparticles for Integrated Bio Imaging (융합 바이오 이미징을 위한 염료 도핑 된 실리카 나노입자의 형광 특성에 관한 연구)

  • Kim, Ki-Chul
    • Journal of Convergence for Information Technology
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    • v.8 no.5
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    • pp.45-50
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    • 2018
  • The functional nanomaterials of fluorescent dye-doped silica nanoparticles(NPs) are applied to bio applications such as bio-labeling of DNA micro-array, and bio-imaging. Organic dye-doped fluorescent silica NPs exhibit excellent bio-compatibility, non-toxic, and highly hydrophilic properties. In this study, organic fluorescent dyes were dissolved in ethanol, and deionized(DI) water. Organic fluorescent dyes were physically adsorbed to silica NPs and chemically doped to silica NPs. The fluorescence characteristics(FLC) was investigated by UV lamp irradiation of 365 nm wavelength. As results, the FLC of dye-doped silica NPs exhibits better than dye-adsorbed silica NPs and the FLC was improved with the increase of concentration of doped-dyes. The fluorescent organic dyes were well dissolved in ethanol than DI water. The photostability of dye-doped silica NPs was superior than pure fluorescent organic dye. The FLC of optimized dye-doped silica NPs would be applied to agent of non-invasive fluorescence bio-imaging in live cell and in vivo.

고등식물에 미치는 항생물질의 영향 (제4보) - 대두 Aminoacid metabolism에 미치는 항생물질의 영향에 대하여

  • 이민재;이영록
    • YAKHAK HOEJI
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    • v.3 no.1
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    • pp.4-9
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    • 1957
  • Effects of antibioties on micro-organism have been reported by many scientists, such as Krampitz and Werkman, Fisher, Gale and Rodwell, Klimick Cavalito and Bailey, Umbreit, etc. On the mechanism by which penicillin act, Fisher(1947), Platt(1947), and Cavallito, considered that penicillin might act on bacteria by inhibiting with the normal function of SH-group of glutathione in the metabolism of the cell. Resenbrance of penicillin to gultathione in structure and the inactivation of penicillin by cysteine make us approve of the above inhibiting theory of SH-group. Galland (1947) and Schmidt (1947) reported that penicillin inhibited the activity of ribonuclease, Phosphatase, and mononucleotidase. Gale (1948) discovered that the gram positive bacteria had lost the power to uptake glutamic acid by ribonucleic acid in the medium contained penicillin: growth of gram positive organism was inhibited by the results that penicillin inhibited the uptake of amino acid byribonucleic acid, acting on ribonucleic acid of gram positive bacteria. Hotchkiss (1950) cultured S. aureus in the medium contained glucose and amino acids, and studied the effect of penicillin on protein synthesis. Peptide formation in living cells was inhibited by penicillin, while amono acid was utilized as before the addition of penicillin. On the otherhand, Binkley (1951) found penicillin interfered hydrolase of glutath one, and Hans (1950) reported penicillin inhibited the transpeptidation. On the machanism by which streptomycin acts. Cohen (1947) reported steptomycin made a irreversible complex with desoxyribonucleic acid, by the fact that desoxyribonucleic acid formed the precipitates with diguanide group of steptomycin. Zeller (1951) reported, on the other hand, streptomycin inhibited diamine oxidease. Geiger (1947) and Umbreit (1949) reported that steptomycin inhibited condensation of oxaloacetate and pyruvate in E. Coli and Oginsky et al (1949) reported steptomycin inhibited oxaloacetate-pyruvate reaction in Kreb's cycle. On the mechanism by which terramycin acts, Hahn & Wisseman (1951) reported that the formation of adaptive enzyme was inhibited by terramycin in E. Coli cultivated in the medium contained loctose, and that the protein synthesis was inhibited by terramycin. However, effects of antibiotics on amino acid metabolism have not been discussed much in spite of its important role in living cells. Especislly, effects of anitibiotics on higher plants have scarcely been reported. Here, to prove the effect of antibiotics on higher plants, and the mechanism by which, through amino acid metabolism, they promote or inhibit growth of plants, amino acids in bean plants treated with penicillin, streptomycin, and terramycin were analyzed by paper chromatography. And to clarify the antagonis of cysteine (as SH-group) against penicillin, through amino acid metabolism, amino acids in bean plants treated with cystene and penicillin, at the same time, were also analyzed.

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Development of a Commercial Process for Micro-Encapsulation of Lactic Acid Bacteria Using Sodium Alginate (알긴산 나트륨을 이용한 유산균 캡슐화의 상업화 공정 개발)

  • Kim, Jiyeon;You, Seong-sik
    • Korean Chemical Engineering Research
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    • v.55 no.3
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    • pp.313-321
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    • 2017
  • We aimed to develop commercialization process of encapsulation which is superior in productivity compared to existing methods by using sodium alginate. Also, in the same process, sodium alginate with chitosan was used to encapsulate lactic acid bacteria with the same process and then the viable cell counts of the two encapsulated lactic acid bacteria were compared. As a test result of the fluidized drying process developed by the present researchers, it was found that the drying time was shortened by 15 to 20 hours compared to the freeze drying method, but the number of viable lactic acid bacteria was about 75% as compared with freeze drying. However, considering the cost and time of drying, it can be confirmed that the commercialization process is possible by the fluidized bed drying method. When the number of viable cells of Ca-alginate capsule and Chitosan-alginate capsule were compared, it was confirmed that there were about $1{\times}10^9$ or more bacteria in the former and about $1{\times}10^3$ in the latter. The lactic acid bacterium capsules prepared by the present technique were stable for 96 hours or more at pH 4.65 and 6.01, but disappeared within 1 hour at pH 7.07 and 8.35. This suggests that the disintegration of lactic acid bacteria can be easily occurred in small and large intestine.