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Sample records for high-purity factor ix

  1. Inactivation and clearance of viruses during the manufacture of high purity factor IX.

    PubMed

    Johnston, A; Macgregor, A; Borovec, S; Hattarki, M; Stuckly, K; Anderson, D; Goss, N H; Oates, A; Uren, E

    2000-09-01

    Haemophilia is a bleeding disorder characterised by a deficiency in Factor IX. Replacement therapy in the form of a Factor IX concentrate is a widely accepted practice. In this paper we describe a double virus inactivated chromatographic process for producing a high purity Factor IX product, MonoFIX((R))-VF. The process involves separation of the prothrombin complex by cryoprecipitation, fraction I precipitation and DEAE-cellulose adsorption, further ion-exchange chromatography of crude Factor IX, followed by solvent/detergent treatment. Heparin affinity chromatography is then used to further purify Factor IX. Final nanofiltration is sequential through 35 nm then 15 nm membrane filters. The principal virus inactivation/removal steps are solvent/detergent treatment and nanofiltration and the partitioning of relevant and model viruses provides further reduction in virus load through the production process.Solvent/detergent treatment was shown to achieve log reduction factors of 4.5 for HIV-1, 5.1 for Sindbis virus, 6.1 for vesicular stomatitis virus (VSV), 5.1 for bovine viral diarrhoea virus (BVDV) and 5.3 for pseudorabies virus (PRV). BVDV is a model for hepatitis C virus (HCV), and pseudorabies virus (PRV), like hepatitis B virus (HBV) is an enveloped DNA virus. Using scaled down models of the production process, we have also demonstrated the neutralization/partitioning of at least 6 logs of hepatitis A virus (HAV) during cryoprecipitation, Fraction I precipitation, and the DEAE adsorption and elution step, and a further 1.6 log reduction in HAV load as a result of heparin affinity chromatography. The log reduction factors for HAV as a result of the second ion-exchange chromatography step and as a result of enhanced neutralisation associated with solvent/detergent treatment were not significant. Nanofiltration was shown to contribute a further log reduction factor of 6.7 for HAV and 5.8 for BVDV indicating that log reduction factors of this order would be obtained

  2. Activation of human factor IX (Christmas factor).

    PubMed Central

    Di Scipio, R G; Kurachi, K; Davie, E W

    1978-01-01

    Human Factor IX (Christmas factor) is a single-chain plasma glycoprotein (mol wt 57,000) that participates in the middle phase of the intrinsic pathway of blood coagulation. It is present in plasma as a zymogen and is converted to a serine protease, Factor IXabeta, by Factor XIa (activated plasma thromboplastin antecedent) in the presence of calcium ions. In the activation reaction, two internal peptide bonds are hydrolyzed in Factor IX. These cleavages occur at a specific arginyl-alanine peptide bond and a specific arginyl-valine peptide bond. This results in the release of an activation peptide (mol wt approximately equal to 11,000) from the internal region of the precursor molecule and the generation of Factor IXabeta (mol wt approximately equal to 46,000). Factor IXabeta is composed of a light chain (mol wt approximately equal to 18,000) and a heavy chain (mol wt approximately equal to 28,000), and these chains are held together by a disulfide bond(s). The light chain originates from the amino terminal portion of the precursor molecule and has an amino terminal sequence of Tyr-Asn-Ser-Gly-Lys. The heavy chain originates from the carboxyl terminal region of the precursor molecule and contains an amino terminal sequence of Val-Val-Gly-Gly-Glu. The heavy chain of Factor IXabeta also contains the active site sequence of Phe-Cys-Ala-Gly-Phe-His-Glu-Gly-Arg-Asp-Ser-Cys-Gln-Gly-Asp-SER-Gly-Gly-Pro. The active site serine residue is shown in capital letters. Factor IX is also converted to Factor IXaalpha by a protease from Russell's viper venom. This activation reaction, however, occurs in a single step and involves only the cleavage of the internal arginyl-valine peptide bond. Human Factor IXabeta was inhibited by human antithrombin III by the formation of a one-to-one complex of enzyme and inhibitor. In this reaction, the inhibitor was tightly bound to the heavy chain of the enzyme. These data indicate that the mechanism of activation of human Factor IX and its

  3. High purity tungsten targets

    NASA Technical Reports Server (NTRS)

    1975-01-01

    High purity tungsten, which is used for targets in X-ray tubes was considered for space processing. The demand for X-ray tubes was calculated using the growth rates for dental and medical X-ray machines. It is concluded that the cost benefits are uncertain.

  4. In vitro and in vivo characterization of a high-purity, solvent/detergent-treated factor VIII concentrate: evidence for its therapeutic efficacy in von Willebrand's disease.

    PubMed

    Mazurier, C; De Romeuf, C; Parquet-Gernez, A; Goudemand, M

    1989-07-01

    A factor VIII (FVIII) concentrate, virus-inactivated by the solvent/detergent procedure, was studied in vitro. In contrast with most high-purity, virus-inactivated FVIII concentrates, it contains not only high levels of von Willebrand factor (vWF) antigen and ristocetin cofactor activity but also high molecular weight forms of von Willebrand factor. Furthermore, it is able to promote platelet adhesion on collagen in a perfusion system. In vivo studies performed in patients with different types of von Willebrand's disease provided evidence that this concentrate corrects Duke's bleeding time and prevents or stops haemorrhages. Thus, the particular advantages of this FVIII/vWF preparation are safety, low content of contamination proteins, and efficacy in von Willebrand's disease.

  5. Evaluation of factor IX deficiency by interdigitated electrode (IDE)

    NASA Astrophysics Data System (ADS)

    Gopinath, Subash C. B.; Hashim, Uda; Uda, M. N. A.

    2017-03-01

    Factor IX deficiency is the main cause of hemophilia A and B. This a severe excessive bleeding disorder that can even kill the patient if not treated with the right prescription of Factor IX hormone to stop the bleeding. The bleeding can be caused by an injury or even a sudden bleeding in some very rare cases. To find the Factor IX effectiveness and to understand the deficiency more carefully for the future of medicine, experiments are conducted to test the Factor IX using the Interdigitated Electrode (IDE) and gold Nanoparticle with the help of Nanoelectrical technology.

  6. Cleavage and activation of human factor IX by serine proteases

    SciTech Connect

    Enfield, D.L.; Thompson, A.R.

    1984-10-01

    Human factor IX circulates as a single-chain glycoprotein. Upon activation in vitro, it is cleaved into disulfide-linked light and heavy chains and an activation peptide. After reduction of activated /sup 125/I-factor IX, the heavy and light chains are readily identified by gel electrophoresis. A direct, immunoradiometric assay for factor IXa was developed to assess activation of factor IX for proteases that cleaved it. The assay utilized radiolabeled antithrombin III with heparin to identify the active site and antibodies to distinguish factor IX. After cleavage of factor IX by factor XIa, factor VIIa-tissue thromboplastin complex, or the factor X-activating enzyme from Russell's viper venom, antithrombin III bound readily to factor IXa. Cleavage of /sup 125/I-factor IX by trypsin, chymotrypsin, and granulocyte elastase in the presence of calcium yielded major polypeptide fragments of the sizes of the factor XIa-generated light and heavy chains. When the immunoradiometric assay was used to assess trypsin-cleaved factor IX, the product bound antithrombin III, but not maximally. After digesting with insolubilized trypsin, clotting activity confirmed activation. In evaluating activation of factor IX, physical evidence of activation cleavages does not necessarily correlate with generation of an active site.

  7. Labeled factor IX kinetics in patients with hemophilia-B

    SciTech Connect

    Smith, K.J.; Thompson, A.R.

    1981-09-01

    Labeled factor IX was infused five time into four patients with hemophilia-B. Ten-minute plasma recovery average 35% (SD +/- 2) and the mean T 1/2 beta-phase elimination was 23 hr (+/- 5). No alteration in the postinfusion 125I-factor-IX could be detected by radioautography of plasma samples run on polyacrylamide gels or on crossed-immunoelectrophoresis. Label was excreted into the urine as free 125I-iodide. Kinetics were similar when the labeled preparation was infused alone or with a commercial concentrate containing unlabeled factor IX. Infusion of factor IX in man is best described by a two-compartment open pharmacokinetic model where factor IX is distributed in a space larger than the plasma volume.

  8. Production of high purity radiothallium

    DOEpatents

    Lebowitz, Elliot; Greene, Margaret W.

    1976-11-23

    The method of producing high purity thallium-201 for use as a myocardial scanning agent comprising the steps of irradiating a thallium target with protons to give the reaction .sup.203 Tl(p,3n) .sup.201.sub.Pb, separating in ion exchange columns the lead from the thallium isotopes, permitting the lead to decay, and then purifying the thallium solution and converting the thallium present to thallous form in which it can be used.

  9. Preparation of high purity phosphorus

    DOEpatents

    Rupp, Arthur F.; Woo, David V.

    1981-01-01

    High purity phosphorus and phosphorus compounds are prepared by first reacting H.sub.3 PO.sub.4 with a lead compound such as PbO to form Pb.sub.3 (PO.sub.4).sub.2. The Pb.sub.3 (PO.sub.4).sub.2 is reduced with H.sub.2 at a temperature sufficient to form gaseous phosphorus which can be recovered as a high purity phosphorus product. Phosphorus compounds can be easily prepared by reacting the phosphorus product with gaseous reactants. For example, the phosphorus product is reacted with gaseous Cl.sub.2 to form PCl.sub.5. PCl.sub.5 is reduced to PCl.sub.3 by contacting it in the gaseous phase with solid elemental phosphorus. POCl.sub.3 can be prepared by contacting PCl.sub.5 in the gaseous phase with solid P.sub.2 O.sub.5. The general process is particularly suitable for the preparation of radiophosphorus compounds.

  10. Muscle as a target for supplementary factor IX gene transfer.

    PubMed

    Hoffman, Brad E; Dobrzynski, Eric; Wang, Lixin; Hirao, Lauren; Mingozzi, Federico; Cao, Ou; Herzog, Roland W

    2007-07-01

    Immune responses to the factor IX (F.IX) transgene product are a concern in gene therapy for the X-linked bleeding disorder hemophilia B. The risk for such responses is determined by several factors, including the vector, target tissue, and others. Previously, we have demonstrated that hepatic gene transfer with adeno-associated viral (AAV) vectors can induce F.IX-specific immune tolerance. Muscle-derived F.IX expression, however, is limited by a local immune response. Here, skeletal muscle was investigated as a target for supplemental gene transfer. Given the low invasiveness of intramuscular injections, this route would be ideal for secondary gene transfer, thereby boosting levels of transgene expression. However, this is feasible only if immune tolerance established by compartmentalization of expression to the liver extends to other sites. Immune tolerance to human F.IX established by prior hepatic AAV-2 gene transfer was maintained after subsequent injection of AAV-1 or adenoviral vector into skeletal muscle, and tolerized mice failed to form antibodies or an interferon (IFN)-gamma(+) T cell response to human F.IX. A sustained increase in systemic transgene expression was obtained for AAV-1, whereas an increase after adenoviral gene transfer was transient. A CD8(+) T cell response specifically against adenovirus-transduced fibers was observed, suggesting that cytotoxic T cell responses against viral antigens were sufficient to eliminate expression in muscle. In summary, the data demonstrate that supplemental F.IX gene transfer to skeletal muscle does not break tolerance achieved by liver-derived expression. The approach is efficacious, if the vector for muscle gene transfer does not express immunogenic viral proteins.

  11. High purity silica reflective heat shield development

    NASA Technical Reports Server (NTRS)

    Nachtscheim, P. R.; Blome, J. C.

    1976-01-01

    A hyperpure vitreous silica material is being developed for use as a reflective and ablative heat shield for planetary entry. Various purity grades and forms of raw materials were evaluated along with various processing methods. Slip casting of high purity grain was selected as the best processing method, resulting in a highly reflective material in the wavelength bands of interest (the visible and ultraviolet regions). The selected material was characterized with respect to optical, mechanical and physical properties using a limited number of specimens. The process has been scaled up to produce a one-half scale heat shield (18 in. dia.) (45.72 cm) for a Jupiter entry vehicle. This work is now being extended to improve the structural safety factor of the heat shield by making hyperpure silica material tougher through the addition of silica fibers.

  12. Kinetics of the Factor XIa catalyzed activation of human blood coagulation Factor IX

    SciTech Connect

    Walsh, P.N.; Bradford, H.; Sinha, D.; Piperno, J.R.; Tuszynski, G.P.

    1984-05-01

    The kinetics of activation of human Factor IX by human Factor XIa was studied by measuring the release of a trichloroacetic acid-soluble tritium-labeled activation peptide from Factor IX. Initial rates of trichloroacetic acid-soluble /sup 3/H-release were linear over 10-30 min of incubation of Factor IX (88 nM) with CaCl/sub 2/ (5 mM) and with pure (greater than 98%) Factor XIa (0.06-1.3 nM), which was prepared by incubating human Factor XI with bovine Factor XIIa. Release of /sup 3/H preceded the appearance of Factor IXa activity, and the percentage of /sup 3/H released remained constant when the mole fraction of /sup 3/H-labeled and unlabeled Factor IX was varied and the total Factor IX concentration remained constant. A linear correlation (r greater than 0.98, P less than 0.001) was observed between initial rates of /sup 3/H-release and the concentration of Factor XIa, measured by chromogenic assay and by radioimmunoassay and added at a Factor IX:Factor XIa molar ratio of 70-5,600. Kinetic parameters, determined by Lineweaver-Burk analysis, include K/sub m/ (0.49 microM) of about five- to sixfold higher than the plasma Factor IX concentration, which could therefore regulate the reaction. The catalytic constant (k/sub cat/) (7.7/s) is approximately 20-50 times higher than that reported by Zur and Nemerson for Factor IX activation by Factor VIIa plus tissue factor. Therefore, depending on the relative amounts of Factor XIa and Factor VIIa generated in vivo and other factors which may influence reaction rates, these kinetic parameters provide part of the information required for assessing the relative contributions of the intrinsic and extrinsic pathways to Factor IX activation, and suggest that the Factor XIa catalyzed reaction is physiologically significant.

  13. New polymorphic variants of human blood clotting factor IX

    SciTech Connect

    Surin, V.L.; Luk`yanenko, A.V.; Tagiev, A.F.; Smirnova, O.V.; Plutalov, O.V.; Berlin, Yu.A.

    1995-04-01

    The polymorphism of Alu-repeats, which are located in the introns of the human factor IX gene (copies 1-3), was studied. To identify polymorphic variants, direct sequencing of PCR products that contained appropriate repeats was used. In each case, 20 unrelated X chromosomes were studied. A polymorphic Dra I site was found near the 3{prime}-end of Alu copy 3 within the region of the polyA tract. A PCR-based testing system with internal control of restriction hydrolysis was suggested. Testing 81 unrelated X chromosomes revealed that the frequency of the polymorphic Dra I site is 0.23. Taq I polymorphism, which was revealed in Alu copy 4 of factor IX gene in our previous work, was found to be closely linked to Dra I polymorphism. Studies in linkage between different types of polymorphisms of the factor IX gene revealed the presence of a rare polymorphism in intron a that was located within the same minisatellite region as the known polymorphic insertion 50 bp/Dde I. However, the size of the insertion in our case was 26 bp. Only one polymorphic variant was found among over 150 unrelated X chromosomes derived from humans from Moscow and its vicinity. 10 refs., 4 figs., 1 tab.

  14. APPARATUS FOR HIGH PURITY METAL RECOVERY

    DOEpatents

    Magel, T.T.

    1959-02-10

    An apparatus is described for preparing high purity metal such as uranium, plutonium and the like from an impure mass of the same metal. The apparatus is arranged so that the impure metal is heated and swept by a stream of hydrogen gas bearing a halogen such as iodine. The volatiie metal halide formed is carried on to a hot filament where the metal halide is decomposed and the molten high purity metal is collected in a rceeiver below

  15. Protein sieving characteristics of sub-20-nm pore size filters at varying ionic strength during nanofiltration of Coagulation Factor IX.

    PubMed

    Winkler, Clint J; Jorba, Nuria; Shitanishi, Kenneth T; Herring, Steven W

    2013-05-01

    Nanofiltration assures that protein therapeutics are free of adventitious agents such as viruses. Nanofilter pores must allow passage of protein drugs but be small enough to retain viruses. Five nanofilters have been evaluated to identify those that can be used interchangeably to yield a high purity Coagulation Factor IX product. When product preparations prior to nanofiltration were analyzed using electrophoresis, Western blot, liquid chromatography - tandem mass spectrometry and size exclusion HPLC, factor IX, inter - α - trypsin inhibitor and C4b binding protein (C4BP) were observed. C4BP was removed from product by all five nanofilters when nanofiltration was performed at physiological ionic strength. However, at high ionic strength, C4BP was removed by only two nanofilters. HPLC indicated that the Stokes radius of C4BP was larger at low ionic strength than at high ionic strength. The results suggest that C4BP exists in an open conformation at physiological ionic strength and is removed by nanofiltration whereas, at high ionic strength, the protein collapses to an extent that allows passage through some nanofilters. Manufacturers should be aware that protein contaminants in other nanofiltered protein drugs could behave similarly and conditions of nanofiltration must be evaluated to ensure consistent product purity.

  16. Long-Acting Recombinant Fusion Protein Linking Coagulation Factor IX with Albumin (rIX-FP) in Children

    PubMed Central

    Chambost, Hervé; Male, Christoph; Lambert, Thierry; Halimeh, Susan; Chernova, Tatiana; Mancuso, Maria Elisa; Curtin, Julie; Voigt, Christine; Li, Yanyan; Jacobs, Iris; Santagostino, Elena

    2016-01-01

    Summary A global phase 3 study evaluated the pharmacokinetics, efficacy and safety of a recombinant fusion protein linking coagulation factor IX with albumin (rIX-FP) in 27 previously treated male children (1–11 years) with severe and moderately severe haemophilia B (factor IX [FIX] activity ≤2 IU/dl). All patients received routine prophylaxis once every seven days for up to 77 weeks, and treated any bleeding episodes on-demand. The mean terminal half-life of rIX-FP was 91.4 hours (h), 4.3-fold longer than previous FIX treatment and clearance was 1.11 ml/h/kg, 6.4-fold slower than previous FIX treatment. The median (Q1, Q3) annualised spontaneous bleeding rate was 0.00 (0.00, 0.91) and was similar between the <6 years and ≥6 years age groups, with a weekly median prophylactic dose of 46 IU/kg. In addition, patients maintained a median trough level of 13.4 IU/dl FIX activity on weekly prophylaxis. Overall, 97.2% of bleeding episodes were successfully treated with one or two injections of rIX-FP (95% CI: 92% to 99%), 88.7% with one injection, and 96% of the treatments were rated effective (excellent or good) by the Investigator. No patient developed FIX inhibitors and no safety concerns were identified. These results indicate that rIX-FP is safe and effective for preventing and treating bleeding episodes in children with haemophilia B with weekly prophylaxis. Routine prophylaxis with rIX-FP at treatment intervals of up to 14 days are currently being investigated in children with severe and moderately severe haemophilia B. Clinicaltrials.gov (NCT01662531) PMID:27583313

  17. High purity silane and silicon production

    NASA Technical Reports Server (NTRS)

    Breneman, William C. (Inventor)

    1987-01-01

    Silicon tetrachloride, hydrogen and metallurgical silicon are reacted at about 400.degree.-600.degree. C. and at pressures in excess of 100 psi, and specifically from about 300 up to about 600 psi to form di- and trichlorosilane that is subjected to disproportionation in the presence of an anion exchange resin to form high purity silane. By-product and unreacted materials are recycled, with metallurgical silicon and hydrogen being essentially the only consumed feed materials. The silane product may be further purified, as by means of activated carbon or cryogenic distillation, and decomposed in a fluid bed or free space reactor to form high purity polycrystalline silicon and by-product hydrogen which can be recycled for further use. The process results in simplified waste disposal operations and enhances the overall conversion of metallurgical grade silicon to silane and high purity silicon for solar cell and semiconductor silicon applications.

  18. The endothelial cell binding determinant of human factor IX resides in the. gamma. -carboxyglutamic acid domain

    SciTech Connect

    Toomey, J.R.; Roberts, H.R.; Stafford, D.W. ); Smith, K.J. United Blood Services, Albuquerque, NM )

    1992-02-18

    The blood coagulation factor IX(a) binds specifically to a site on endothelial cells with a K{sub d} of 2.0-3.0 nM. A number of previous studies have attempted to define the region(s) of factor IX(a) that mediate this interaction. These studies suggested that there are two regions of factor IX(a), the {gamma}-carboxyglutamic acid (Gla) domain and the epidermal growth factor like (EGF-like) domains, that mediate high-affinity binding to endothelial cells. Recently, however, the participation of the EGF1 domain has been excluded from the interaction. This indicated that if there was an EGF component of factor IX contributing to the binding affinity, then it must be in the second EGF-like domain. In order to further evaluate this relationship, the authors performed competitive binding experiments between {sup 125}I plasma factor IX and a set of six chimeric proteins composed of portions of factor VII and factor IX. The data suggest that the high-affinity interaction between factor IX and the endothelial cell binding site is mediated by the factor IX Gla domain and that the factor IX EGF domains are not involved in binding specificity.

  19. Major role of local immune responses in antibody formation to factor IX in AAV gene transfer.

    PubMed

    Wang, L; Cao, O; Swalm, B; Dobrzynski, E; Mingozzi, F; Herzog, R W

    2005-10-01

    The risk of an immune response to the coagulation factor IX (F.IX) transgene product is a concern in gene therapy for the X-linked bleeding disorder hemophilia B. In order to investigate the mechanism of F.IX-specific lymphocyte activation in the context of adeno-associated viral (AAV) gene transfer to skeletal muscle, we injected AAV-2 vector expressing human F.IX (hF.IX) into outbred immune-competent mice. Systemic hF.IX levels were transiently detected in the circulation, but diminished concomitant with activation of CD4+ T and B cells. ELISPOT assays documented robust responses to hF.IX in the draining lymph nodes of injected muscle by day 14. Formation of inhibitory antibodies to hF.IX was observed over a wide range of vector doses, with increased doses causing stronger immune responses. A prolonged inflammatory reaction in muscle started at 1.5-2 months, but ultimately failed to eliminate transgene expression. By 1.5 months, hF.IX antigen re-emerged in circulation in approximately 70% of animals injected with high vector dose. Hepatic gene transfer elicited only infrequent and weaker immune responses, with higher vector doses causing a reduction in T-cell responses to hF.IX. In summary, the data document substantial influence of target tissue, local antigen presentation, and antigen levels on lymphocyte responses to F.IX.

  20. Characterization of the clotting activities of structurally different forms of activated factor IX. Enzymatic properties of normal human factor IXa alpha, factor IXa beta, and activated factor IX Chapel Hill.

    PubMed Central

    Griffith, M J; Breitkreutz, L; Trapp, H; Briet, E; Noyes, C M; Lundblad, R L; Roberts, H R

    1985-01-01

    Two structurally different forms of activated human Factor IX (Factor IXa alpha and IXa beta) have been previously reported to have essentially identical clotting activity in vitro. Although it has been shown that activated Factor IX Chapel Hill, an abnormal Factor IX isolated from the plasma of a patient with mild hemophilia B, and normal Factor IXa alpha are structurally very similar, the clotting activity of activated Factor IX Chapel Hill is much lower (approximately fivefold) than that of normal Factor IXa beta. In the present study we have prepared activated Factor IX by incubating human Factor IX with calcium and Russell's viper venom covalently bound to agarose. Fractionation of the activated Factor IX by high-performance liquid chromatography demonstrated the presence of both Factors IXa alpha and IXa beta. On the basis of active site concentration, determined by titration with antithrombin III, the clotting activities of activated Factor IX Chapel Hill and IXa alpha were similar, but both activities were less than 20% of the clotting activity of Factor IXa beta. Activated Factor IX activity was also measured in the absence of calcium, phospholipid, and Factor VIII, by determination of the rate of Factor X activation in the presence of polylysine. In the presence of polylysine, the rates of Factor X activation by activated Factor IX Chapel Hill, Factor IXa alpha, and Factor IXa beta were essentially identical. We conclude that the clotting activity of activated Factor IX Chapel Hill is reduced when compared with that of Factor IXa beta but essentially normal when compared with that of Factor IXa alpha. PMID:3871202

  1. Method of high purity silane preparation

    DOEpatents

    Tsuo, Y. Simon; Belov, Eugene P.; Gerlivanov, Vadim G.; Zadde, Vitali V.; Kleschevnikova, Solomonida I.; Korneev, Nikolai N.; Lebedev, Eugene N.; Pinov, Akhsarbek B.; Ryabenko, Eugene A.; Strebkov, Dmitry S.; Chernyshev, Eugene A.

    2000-01-01

    A process for the preparation of high purity silane, suitable for forming thin layer silicon structures in various semiconductor devices and high purity poly- and single crystal silicon for a variety of applications, is provided. Synthesis of high-purity silane starts with a temperature assisted reaction of metallurgical silicon with alcohol in the presence of a catalyst. Alcoxysilanes formed in the silicon-alcohol reaction are separated from other products and purified. Simultaneous reduction and oxidation of alcoxysilanes produces gaseous silane and liquid secondary products, including, active part of a catalyst, tetra-alcoxysilanes, and impurity compounds having silicon-hydrogen bonds. Silane is purified by an impurity adsorption technique. Unreacted alcohol is extracted and returned to the reaction with silicon. Concentrated mixture of alcoxysilanes undergoes simultaneous oxidation and reduction in the presence of a catalyst at the temperature -20.degree. C. to +40.degree. C. during 1 to 50 hours. Tetra-alcoxysilane extracted from liquid products of simultaneous oxidation and reduction reaction is directed to a complete hydrolysis. Complete hydrolysis of tetra-alcoxysilane results in formation of industrial silica sol and alcohol. Alcohol is dehydrated by tetra-alcoxysilane and returned to the reaction with silicon.

  2. Evidence for a prevalent dimorphism in the activation peptide of human coagulation factor IX.

    PubMed Central

    McGraw, R A; Davis, L M; Noyes, C M; Lundblad, R L; Roberts, H R; Graham, J B; Stafford, D W

    1985-01-01

    We have independently isolated and characterized cDNA and genomic clones for the human coagulation factor IX. Sequence analysis in both cases indicates that threonine is encoded by the triplet ACT as the third residue of the activation peptide. This is in agreement with some earlier reports but in disagreement with others that show the alanine triplet GCT at this position. The discrepancy can thus be accounted for by natural variation of a single nucleotide in the normal population. Amino acid sequence analyses of activated factor IX from plasma samples of four individuals yielded two cases of alanine and two cases of threonine at the third position of the activation peptide. In factor IX from pooled plasma and in factor IX from a heterozygous individual, however, both alanine and threonine were found. Taken together, the findings show that a prevalent nondeleterious dimorphism exists in the activation peptide of human coagulation factor IX. PMID:3857619

  3. Method for preparing high purity vanadium

    DOEpatents

    Schmidt, F.; Carlson, O.N.

    1984-05-16

    A method for preparing high purity vanadium having a low silicon content has been developed. Vanadium pentoxide is reduced with a stoichiometric, or slightly deficient amount of aluminum to produce a vanadium-aluminum alloy containing an excess of oxygen. Silicon is removed by electron-beam melting the alloy under oxidizing conditions to promote the formation of SiO which is volatile at elevated temperatures. Excess oxygen is removed by heating the alloy in the presence of calcium metal to form calcium oxide.

  4. Method for preparing high purity vanadium

    DOEpatents

    Schmidt, Frederick; Carlson, O. Norman

    1986-09-09

    A method for preparing high purity vanadium having a low silicon content has been developed. Vanadium pentoxide is reduced with a stoichiometric, or slightly deficient amount of aluminum to produce a vanadium-aluminum alloy containing an excess of oxygen. Silicon is removed by electron-beam melting the alloy under oxidizing conditions to promote the formation of SiO which is volatile at elevated temperatures. Excess oxygen is removed by heating the alloy in the presence of calcium metal to form calcium oxide.

  5. Identification of the molecular defect in factor IX Chapel Hill: substitution of histidine for arginine at position 145.

    PubMed Central

    Noyes, C M; Griffith, M J; Roberts, H R; Lundblad, R L

    1983-01-01

    Hemophilia B Chapel Hill is a mild hereditary hemorrhagic disorder in which the factor IX antigen is present in normal amounts but factor IX biological activity is markedly reduced. Previous studies have demonstrated that purified factor IX Chapel Hill has 8% of the activity of normal human factor IX and that the activation of factor IX Chapel Hill is defective in that only one of the two peptide bonds hydrolyzed during activation of normal factor IX is cleaved. The tryptic peptides from normal human factor IX and factor IX Chapel Hill were subjected to analysis by high-performance liquid chromatography. Comparison of the elution profile of the peptides obtained from factor IX Chapel Hill and normal factor IX demonstrated that the tripeptide Leu-Thr-Arg, which is derived from the normal molecule (positions 143-145) immediately amino-terminal from the Arg-Ala peptide bond at 145-146 that is cleaved during the activation of factor IX with factor XIa, was absent in the digest obtained from factor factor IX Chapel Hill. The elongated "activation peptide" from factor factor IX Chapel Hill was obtained by further high-performance liquid chromatographic fractionation and subjected to primary structure analysis. The following sequence, corresponding to positions 143-147, was obtained: Leu-Thr-His-Ala-Glu. Thus, the primary molecular defect in factor factor IX Chapel Hill is the substitution of histidine for arginine at position 145. This substitution precludes cleavage by factor XIa at this peptide bond, and the activation peptide region remains associated with the light chain of factor IXa Chapel Hill. PMID:6603618

  6. Recombinant Human Factor IX Produced from Transgenic Porcine Milk

    PubMed Central

    Lee, Meng-Hwan; Lin, Yin-Shen; Tu, Ching-Fu; Yen, Chon-Ho

    2014-01-01

    Production of biopharmaceuticals from transgenic animal milk is a cost-effective method for highly complex proteins that cannot be efficiently produced using conventional systems such as microorganisms or animal cells. Yields of recombinant human factor IX (rhFIX) produced from transgenic porcine milk under the control of the bovine α-lactalbumin promoter reached 0.25 mg/mL. The rhFIX protein was purified from transgenic porcine milk using a three-column purification scheme after a precipitation step to remove casein. The purified protein had high specific activity and a low ratio of the active form (FIXa). The purified rhFIX had 11.9 γ-carboxyglutamic acid (Gla) residues/mol protein, which approached full occupancy of the 12 potential sites in the Gla domain. The rhFIX was shown to have a higher isoelectric point and lower sialic acid content than plasma-derived FIX (pdFIX). The rhFIX had the same N-glycosylation sites and phosphorylation sites as pdFIX, but had a higher specific activity. These results suggest that rhFIX produced from porcine milk is physiologically active and they support the use of transgenic animals as bioreactors for industrial scale production in milk. PMID:24955355

  7. Process for producing high purity aromatic compounds

    SciTech Connect

    Mayes, W.W.

    1980-05-20

    High-purity C7 and/or C8 aromatic hydrocarbons are produced by reforming a C7 or C8 full boiling carbon number naphtha feed fraction or combinations thereof under reforming conditions of sufficient severity to convert essentially all of the nonaromatic portion of the naphtha feed boiling in the C7 to C8 aromatic boiling range to C7 and/or C8 aromatics, and then separating the reformate by fractional distillation into highpurity fractions of C7 and/or C8 aromatic hydrocarbons. Preferably, the C7 and/or C8 full boiling carbon number naphtha feed fraction is reformed in a plurality of reformer reaction stages with increasingly more severe conditions in order to maximize the yield of the C7 and C8 aromatics.

  8. High purity silica reflective heat shield development

    NASA Technical Reports Server (NTRS)

    Blome, J.

    1974-01-01

    Progress is reported on the development of a high purity reflective heat shield material. Silicon dioxide was selected as the material because it is highly reflective in the correct wavelength band, has good ablation characteristics, is thermal shock resistant, and is readily fabricated to full size at reasonable cost. Conclusions indicate that: reflectance is affected by purity and morphology; the pure material is readily available; required purity and morphology can be maintained with reasonable care; high reflectances are determined (0.99 from 0.4 to 1.2 microns); major processing steps are defined; and the material appears to be cost effective. It is indicated that the materials are developed to the point of readiness for full scale fabrication and characterization.

  9. Workshop on Preserving High Purity Uranium-233

    SciTech Connect

    Krichinsky, Alan M; Giaquinto, Joseph; Canaan, R Douglas {Doug}

    2016-01-01

    A workshop was held on at the MARC X conference to provide a forum for the scientific community to communicate needs for high-purity 233U and its by-products in order to preserve critical items otherwise slated for downblending and disposal. Currently, only a small portion of the U.S. holdings of separated 233U is being preserved. However, many additional kilograms of 233U (>97% pure) still are destined to be downblended which will permanently destroy their potential value for many other applications. It is not likely that this material will ever be replaced due to a lack of operating production capability. Summaries of information conveyed at the workshop and feedback obtained from the scientific community are presented herein.

  10. Factor IX gene analysis in 70 unrelated patients with haemophilia B: description of 13 new mutations.

    PubMed

    Attali, O; Vinciguerra, C; Trzeciak, M C; Durin, A; Pernod, G; Gay, V; Ménart, C; Sobas, F; Dechavanne, M; Négrier, C

    1999-11-01

    Seventy unrelated patients suffering from haemophilia B have been screened for determining the molecular defect and for evaluating the spectrum of factor IX mutations in the Rhône Alpes region in France. Most patients were characterized with respect to factor IX antigen and factor IX coagulant activity. We have used denaturing gradient gel electrophoresis to obtain a full scanning of the whole coding, promoter, and exon flanking sequences of the factor IX gene. This technique enabled us to determine the molecular defect in 68 out of 70 families (97%), and the mutation was further identified in the two last patients with a direct sequencing of the gene. A total of 2 complete gene deletions in patients with antifactor IX inhibitor, 6 small insertions/deletions and 62 point mutations were found. Two of these nucleotide substitutions (Arg145His and Ala233Thr) were detected in 21 patients (30%) suggesting the existence of a local founder effect. Thirteen mutations were previously undescribed, including 7 missense mutations. The detection of mutations in patients affected with haemophilia B may shed some light in the structure-function relationship of factor IX molecule within the coagulation system.

  11. Biaxial deformation in high purity aluminum

    DOE PAGES

    Livescu, V.; Bingert, J. F.; Liu, C.; ...

    2015-09-25

    The convergence of multiple characterization tools has been applied to investigate the relationship of microstructure on damage evolution in high purity aluminum. The extremely coarse grain size of the disc-shaped sample provided a quasi-two dimensional structure from which the location of surface-measured features could be inferred. In particular, the role of pre-existing defects on damage growth was accessible due to the presence of casting porosity in the aluminum. Micro tomography, electron backscatter diffraction, and digital image correlation were applied to interrogate the sample in three dimensions. Recently micro-bulge testing apparatus was used to deform the pre-characterized disc of aluminum inmore » biaxial tension, and related analysis techniques were applied to map local strain fields. Subsequent post-mortem characterization of the failed sample was performed to correlate structure to damaged regions. We determined that strain localization and associated damage was most strongly correlated with grain boundary intersections and plastic anisotropy gradients between grains. Pre-existing voids played less of an apparent role than was perhaps initially expected. Finally, these combined techniques provide insight to the mechanism of damage initiation, propagation, and failure, along with a test bed for predictive damage models incorporating anisotropic microstructural effects.« less

  12. High-purity germanium crystal growing

    SciTech Connect

    Hansen, W.L.; Haller, E.E.

    1982-10-01

    The germanium crystals used for the fabrication of nuclear radiation detectors are required to have a purity and crystalline perfection which is unsurpassed by any other solid material. These crystals should not have a net electrically active impurity concentration greater than 10/sup 10/cm/sup -3/ and be essentially free of charge trapping defects. Such perfect crystals of germanium can be grown only because of the highly favorable chemical and physical properties of this element. However, ten years of laboratory scale and commercial experience has still not made the production of such crystals routine. The origin and control of many impurities and electrically active defect complexes is now fairly well understood but regular production is often interrupted for long periods due to the difficulty of achieving the required high purity or to charge trapping in detectors made from crystals seemingly grown under the required conditions. The compromises involved in the selection of zone refining and crystal grower parts and ambients is discussed and the difficulty in controlling the purity of key elements in the process is emphasized. The consequences of growing in a hydrogen ambient are discussed in detail and it is shown how complexes of neutral defects produce electrically active centers.

  13. Dynamic shear deformation in high purity Fe

    SciTech Connect

    Cerreta, Ellen K; Bingert, John F; Trujillo, Carl P; Lopez, Mike F; Gray, George T

    2009-01-01

    The forced shear test specimen, first developed by Meyer et al. [Meyer L. et al., Critical Adiabatic Shear Strength of Low Alloyed Steel Under Compressive Loading, Metallurgical Applications of Shock Wave and High Strain Rate Phenomena (Marcel Decker, 1986), 657; Hartmann K. et al., Metallurgical Effects on Impact Loaded Materials, Shock Waves and High Strain rate Phenomena in Metals (Plenum, 1981), 325-337.], has been utilized in a number of studies. While the geometry of this specimen does not allow for the microstructure to exactly define the location of shear band formation and the overall mechanical response of a specimen is highly sensitive to the geometry utilized, the forced shear specimen is useful for characterizing the influence of parameters such as strain rate, temperature, strain, and load on the microstructural evolution within a shear band. Additionally, many studies have utilized this geometry to advance the understanding of shear band development. In this study, by varying the geometry, specifically the ratio of the inner hole to the outer hat diameter, the dynamic shear localization response of high purity Fe was examined. Post mortem characterization was performed to quantify the width of the localizations and examine the microstructural and textural evolution of shear deformation in a bcc metal. Increased instability in mechanical response is strongly linked with development of enhanced intergranular misorientations, high angle boundaries, and classical shear textures characterized through orientation distribution functions.

  14. Biaxial deformation in high purity aluminum

    SciTech Connect

    Livescu, V.; Bingert, J. F.; Liu, C.; Lovato, M. L.; Patterson, B. M.

    2015-09-25

    The convergence of multiple characterization tools has been applied to investigate the relationship of microstructure on damage evolution in high purity aluminum. The extremely coarse grain size of the disc-shaped sample provided a quasi-two dimensional structure from which the location of surface-measured features could be inferred. In particular, the role of pre-existing defects on damage growth was accessible due to the presence of casting porosity in the aluminum. Micro tomography, electron backscatter diffraction, and digital image correlation were applied to interrogate the sample in three dimensions. Recently micro-bulge testing apparatus was used to deform the pre-characterized disc of aluminum in biaxial tension, and related analysis techniques were applied to map local strain fields. Subsequent post-mortem characterization of the failed sample was performed to correlate structure to damaged regions. We determined that strain localization and associated damage was most strongly correlated with grain boundary intersections and plastic anisotropy gradients between grains. Pre-existing voids played less of an apparent role than was perhaps initially expected. Finally, these combined techniques provide insight to the mechanism of damage initiation, propagation, and failure, along with a test bed for predictive damage models incorporating anisotropic microstructural effects.

  15. Validation of the manufacturing process used to produce long-acting recombinant factor IX Fc fusion protein.

    PubMed

    McCue, J; Osborne, D; Dumont, J; Peters, R; Mei, B; Pierce, G F; Kobayashi, K; Euwart, D

    2014-07-01

    Recombinant factor IX Fc (rFIXFc) fusion protein is the first of a new class of bioengineered long-acting factors approved for the treatment and prevention of bleeding episodes in haemophilia B. The aim of this work was to describe the manufacturing process for rFIXFc, to assess product quality and to evaluate the capacity of the process to remove impurities and viruses. This manufacturing process utilized a transferable and scalable platform approach established for therapeutic antibody manufacturing and adapted for production of the rFIXFc molecule. rFIXFc was produced using a process free of human- and animal-derived raw materials and a host cell line derived from human embryonic kidney (HEK) 293H cells. The process employed multi-step purification and viral clearance processing, including use of a protein A affinity capture chromatography step, which binds to the Fc portion of the rFIXFc molecule with high affinity and specificity, and a 15 nm pore size virus removal nanofilter. Process validation studies were performed to evaluate identity, purity, activity and safety. The manufacturing process produced rFIXFc with consistent product quality and high purity. Impurity clearance validation studies demonstrated robust and reproducible removal of process-related impurities and adventitious viruses. The rFIXFc manufacturing process produces a highly pure product, free of non-human glycan structures. Validation studies demonstrate that this product is produced with consistent quality and purity. In addition, the scalability and transferability of this process are key attributes to ensure consistent and continuous supply of rFIXFc.

  16. Characteristics of GRIFFIN high-purity germanium clover detectors

    NASA Astrophysics Data System (ADS)

    Rizwan, U.; Garnsworthy, A. B.; Andreoiu, C.; Ball, G. C.; Chester, A.; Domingo, T.; Dunlop, R.; Hackman, G.; Rand, E. T.; Smith, J. K.; Starosta, K.; Svensson, C. E.; Voss, P.; Williams, J.

    2016-06-01

    The Gamma-Ray Infrastructure For Fundamental Investigations of Nuclei, GRIFFIN, is a new experimental facility for radioactive decay studies at the TRIUMF-ISAC laboratory. The performance of the 16 high-purity germanium (HPGe) clover detectors that will make up the GRIFFIN spectrometer is reported. The energy resolution, efficiency, timing resolution, crosstalk and preamplifier properties of each crystal were measured using a combination of analog and digital data acquisition techniques. The absolute efficiency and add-back factors are determined for the energy range of 80-3450 keV. The detectors show excellent performance with an average over all 64 crystals of a FWHM energy resolution of 1.89(6) keV and relative efficiency with respect to a 3 in . × 3 in . NaI detector of 41(1)% at 1.3 MeV.

  17. High-purity silicon for solar cell applications

    NASA Technical Reports Server (NTRS)

    Dosaj, V. D.; Hunt, L. P.; Schei, A.

    1978-01-01

    The article discusses the production of solar cells from high-purity silicon. The process consists of reducing the level of impurities in the raw materials, preventing material contamination before and after entering the furnace, and performing orders-of-magnitude reduction of metal impurity concentrations. The high-purity raw materials are considered with reference to carbon reductants, silica, and graphite electrodes. Attention is also given to smelting experiments used to demonstrate, in an experimental-scale furnace, the production of high-purity SoG-Si. It is found that high-purity silicon may be produced from high-purity quartz and chemically purified charcoal in a 50-kVA arc furnace. The major contamination source is shown to be impurities from the carbon reducing materials.

  18. Collaborative study for the establishment of replacement batches for human coagulation factor IX concentrate reference standards.

    PubMed

    Gray, E; Pickering, W; Hockley, J; Rigsby, P; Weinstein, M; Terao, E; Buchheit, K-H

    2008-12-01

    The European Pharmacopoeia (Ph. Eur.) Biological Reference Preparation (BRP) batch 1, the World Health Organisation (WHO) 3rd International Standard, Human (IS, 96/854) and the FDA Standard for human blood coagulation Factor IX concentrate have been available since 1996, following their establishment by a common collaborative study. Due to dwindling stocks of all three standards, a new WHO-EDQM-FDA tri-partite collaborative study was launched to establish replacement batches. Thirty laboratories from fourteen countries took part in the collaborative study to assign potency values to candidate preparations. Three candidates, one of recombinant and two of human plasma-derived origins, were assayed against the 3rd IS for Blood Coagulation Factor IX, Concentrate, Human (96/854). The 3rd IS for Blood Coagulation Factors II, VII, IX and X, Plasma, Human (99/826) was also included to evaluate the relationship between the factor IX plasma and concentrate unitage. Thirty-two sets of clotting assay results and two sets of chromogenic assay data were analysed. There was a significant difference in potency estimates by these two methods for the recombinant candidate (sample B) and the plasma IS (sample P). Similar potency values were obtained for the plasma derived products (monoclonal antibody- and chromatography-purified factor IX, samples C and D) by clotting and chromogenic assays. For the clotting assays, intra-laboratory variability (GCV) was found to range from 0.5 - 21.7%, with the GCV for the majority of laboratories being less than 10%. Good inter-laboratory agreement, with the majority of the GCV being less than 10% (GCV range = 4.7 - 10.6 %) was also obtained. The mean potency values estimated by the clotting assay using plasma as pre-diluent (as directed by the Ph. Eur. general chapter method) did not differ from values obtained using buffer. Taking into account the preliminary stability data, the intra- and inter-laboratory variability, and the differences

  19. Long-acting recombinant coagulation factor IX albumin fusion protein (rIX-FP) in hemophilia B: results of a phase 3 trial.

    PubMed

    Santagostino, Elena; Martinowitz, Uri; Lissitchkov, Toshko; Pan-Petesch, Brigitte; Hanabusa, Hideji; Oldenburg, Johannes; Boggio, Lisa; Negrier, Claude; Pabinger, Ingrid; von Depka Prondzinski, Mario; Altisent, Carmen; Castaman, Giancarlo; Yamamoto, Koji; Álvarez-Roman, Maria-Teresa; Voigt, Christine; Blackman, Nicole; Jacobs, Iris

    2016-04-07

    A global phase 3 study evaluated the pharmacokinetics, efficacy, and safety of recombinant fusion protein linking coagulation factor IX with albumin (rIX-FP) in 63 previously treated male patients (12-61 years) with severe hemophilia B (factor IX [FIX] activity ≤2%). The study included 2 groups: group 1 patients received routine prophylaxis once every 7 days for 26 weeks, followed by either 7-, 10-, or 14-day prophylaxis regimen for a mean of 50, 38, or 51 weeks, respectively; group 2 patients received on-demand treatment of bleeding episodes for 26 weeks and then switched to a 7-day prophylaxis regimen for a mean of 45 weeks. The mean terminal half-life of rIX-FP was 102 hours, 4.3-fold longer than previous FIX treatment. Patients maintained a mean trough of 20 and 12 IU/dL FIX activity on prophylaxis with rIX-FP 40 IU/kg weekly and 75 IU/kg every 2 weeks, respectively. There was 100% reduction in median annualized spontaneous bleeding rate (AsBR) and 100% resolution of target joints when subjects switched from on-demand to prophylaxis treatment with rIX-FP (P< .0001). The median AsBR was 0.00 for all prophylaxis regimens. Overall, 98.6% of bleeding episodes were treated successfully, including 93.6% that were treated with a single injection. No patient developed an inhibitor, and no safety concerns were identified. These results indicate rIX-FP is safe and effective for preventing and treating bleeding episodes in patients with hemophilia B at dosing regimens of 40 IU/kg weekly and 75 IU/kg every 2 weeks. This trial was registered at www.clinicaltrials.gov as #NCT0101496274.

  20. Long-acting recombinant coagulation factor IX albumin fusion protein (rIX-FP) in hemophilia B: results of a phase 3 trial

    PubMed Central

    Martinowitz, Uri; Lissitchkov, Toshko; Pan-Petesch, Brigitte; Hanabusa, Hideji; Oldenburg, Johannes; Boggio, Lisa; Negrier, Claude; Pabinger, Ingrid; von Depka Prondzinski, Mario; Altisent, Carmen; Castaman, Giancarlo; Yamamoto, Koji; Álvarez-Roman, Maria-Teresa; Voigt, Christine; Blackman, Nicole; Jacobs, Iris

    2016-01-01

    A global phase 3 study evaluated the pharmacokinetics, efficacy, and safety of recombinant fusion protein linking coagulation factor IX with albumin (rIX-FP) in 63 previously treated male patients (12-61 years) with severe hemophilia B (factor IX [FIX] activity ≤2%). The study included 2 groups: group 1 patients received routine prophylaxis once every 7 days for 26 weeks, followed by either 7-, 10-, or 14-day prophylaxis regimen for a mean of 50, 38, or 51 weeks, respectively; group 2 patients received on-demand treatment of bleeding episodes for 26 weeks and then switched to a 7-day prophylaxis regimen for a mean of 45 weeks. The mean terminal half-life of rIX-FP was 102 hours, 4.3-fold longer than previous FIX treatment. Patients maintained a mean trough of 20 and 12 IU/dL FIX activity on prophylaxis with rIX-FP 40 IU/kg weekly and 75 IU/kg every 2 weeks, respectively. There was 100% reduction in median annualized spontaneous bleeding rate (AsBR) and 100% resolution of target joints when subjects switched from on-demand to prophylaxis treatment with rIX-FP (P < .0001). The median AsBR was 0.00 for all prophylaxis regimens. Overall, 98.6% of bleeding episodes were treated successfully, including 93.6% that were treated with a single injection. No patient developed an inhibitor, and no safety concerns were identified. These results indicate rIX-FP is safe and effective for preventing and treating bleeding episodes in patients with hemophilia B at dosing regimens of 40 IU/kg weekly and 75 IU/kg every 2 weeks. This trial was registered at www.clinicaltrials.gov as #NCT0101496274. PMID:26755710

  1. Somatic mosaicism and female-to-female transmission in a kindred with hemophilia B (factor IX deficiency)

    SciTech Connect

    Taylor, S.A.M.; Deugau, K.V.; Lillicrap, D.P. )

    1991-01-01

    Studies have shown that hemophilia B (Christmas disease; factor IX deficiency) results from many different mutations in the factor IX gene, of which {gt}95% are single nulceotide substitutions. This study has identified a previously unreported form of hemophilia B in a patient who was a somatic mosaic for a guanine-to-cytosine transversion at nucleotide 31,170 in the factor IX gene. This point mutation changes the codon for residue 350 in the catalytic domain of factor IX from a cysteine to a serine. The authors used differential termination of primer extension to confirm and measure the degree of mosaicism. The study shows that a varying proportion of cells from hepatic, renal, smooth muscle, and hematopoietic populations possessed normal as well as mutant factor IX sequences. These results indicate that the mutation in this patient occurred either as an uncorrected half-chromatid mutation in the female gamete or as a replication or postreplication error in the initial mitotic divisions of the zygote preceding implantation. In addition, this kindred also contains two females in successive generations who have moderately severe factor IX deficiency. The molecular pathogenesis of this latter phenomenon has been studied and seems to relate to the unaccompanied expression of the mutant factor IX gene consequent upon a second, as yet undefined, genetic event that has prevented inactivation of sequences including the mutant factor IX gene on the X chromosome inherited from the affected male.

  2. Safety and pharmacokinetics of a novel recombinant fusion protein linking coagulation factor IX with albumin (rIX-FP) in hemophilia B patients

    PubMed Central

    Negrier, Claude; Klamroth, Robert; Tiede, Andreas; Pabinger-Fasching, Ingrid; Voigt, Christine; Jacobs, Iris; Morfini, Massimo

    2012-01-01

    A recombinant fusion protein linking coagulation factor IX (FIX) with human albumin (rIX-FP) has been developed to facilitate hemophilia B treatment by less frequent FIX dosing. This first-in-human dose-escalation trial in 25 previously treated subjects with hemophilia B (FIX ≤ 2 IU/dL) examined the safety and pharmacokinetics of 25, 50, and 75 IU/kg rIX-FP. Patients in the 50-IU/kg cohort underwent a comparative pharmacokinetics assessment with their previous FIX product (plasma-derived or recombinant). No allergic reactions or inhibitors were observed. Four mild, possibly treatment-related adverse events were reported. In the 50-IU/kg cohort (13 subjects), the mean half-life of rIX-FP was 92 hours, more than 5 times longer than the subjects' previous FIX product. After 25 or 50 IU/kg rIX-FP administration, the baseline-corrected mean FIX activity remained elevated at day 7 (7.4 IU/dL and 13.4 IU/dL, respectively) and day 14 (2.5 IU/dL and 5.5 IU/dL, respectively). The incremental recovery of rIX-FP was higher than both recombinant and plasma-derived FIX (1.4 vs 0.95 and 1.1 IU/dL per IU/kg, respectively). These results demonstrated both the safety and improved pharmacokinetics of rIX-FP, thus indicating this new product with extended half-life as possibly able to control and prevent bleeding with less frequent injection. The trial was registered at www.clinicaltrials.gov as no. NCT01233440. PMID:22859609

  3. Production of High Purity Niobium Ingots at CBMM

    NASA Astrophysics Data System (ADS)

    de Moura, Lourenço; de Faria Sousa, Clovis Antonio; Cruz, Edmundo Burgos

    2011-03-01

    CBMM is a fully integrated company, from the mine to the end line of the production chain, supplying different niobium products to the world market: ferroniobium, nickelniobium, niobium pentoxide and high purity metallic niobium. This high purity metallic niobium has long been known to exhibit superconductivity below 9.25 Kelvin. This characteristic has the potential to bring technological benefits for many different areas such as medicine, computing and environment. This paper presents the raw material requirements as well as CBMM experience on producing high purity niobium ingots. The results prove that CBMM material can be the best solution for special applications such as low cost superconductive radiofrequency cavities.

  4. Production of High Purity Niobium Ingots at CBMM

    SciTech Connect

    Moura, Lourenco de; Faria Sousa, Clovis Antonio de; Burgos Cruz, Edmundo

    2011-03-31

    CBMM is a fully integrated company, from the mine to the end line of the production chain, supplying different niobium products to the world market: ferroniobium, nickelniobium, niobium pentoxide and high purity metallic niobium. This high purity metallic niobium has long been known to exhibit superconductivity below 9.25 Kelvin. This characteristic has the potential to bring technological benefits for many different areas such as medicine, computing and environment. This paper presents the raw material requirements as well as CBMM experience on producing high purity niobium ingots. The results prove that CBMM material can be the best solution for special applications such as low cost superconductive radiofrequency cavities.

  5. Analysis of trace halocarbon contaminants in ultra high purity helium

    NASA Technical Reports Server (NTRS)

    Fewell, Larry L.

    1994-01-01

    This study describes the analysis of ultra high purity helium. Purification studies were conducted and containment removal was effected by the utilization of solid adsorbent purge-trap systems at cryogenic temperatures. Volatile organic compounds in ultra high purity helium were adsorbed on a solid adsorbent-cryogenic trap, and thermally desorbed trace halocarbon and other contaminants were analyzed by combined gas chromatography-mass spectrometry.

  6. Delta Doping High Purity CCDs and CMOS for LSST

    NASA Technical Reports Server (NTRS)

    Blacksberg, Jordana; Nikzad, Shouleh; Hoenk, Michael; Elliott, S. Tom; Bebek, Chris; Holland, Steve; Kolbe, Bill

    2006-01-01

    A viewgraph presentation describing delta doping high purity CCD's and CMOS for LSST is shown. The topics include: 1) Overview of JPL s versatile back-surface process for CCDs and CMOS; 2) Application to SNAP and ORION missions; 3) Delta doping as a back-surface electrode for fully depleted LBNL CCDs; 4) Delta doping high purity CCDs for SNAP and ORION; 5) JPL CMP thinning process development; and 6) Antireflection coating process development.

  7. Expression of human factor IX in rat capillary endothelial cells: Toward somatic gene therapy for hemophilia B

    SciTech Connect

    Shounan Yao; Wilson, J.M.; Nabel, E.G.; Kurachi, Sumiko; Hachiya, H.L.; Kurachi, Kotoku )

    1991-09-15

    In aiming to develop a gene therapy approach for hemophilia B, the authors expressed and characterized human factor IX in rat capillary endothelial cells (CECs). Moloney murine leukemia virus-derived retrovirus vectors that contain human factor IX cDNA linked to heterologous promoters and the neomycin-resistant gene were constructed and employed to prepare recombinant retroviruses. Rat CECs and NIH 3T3 cells infected with these viruses were selected with the neomycin analogue, G418 sulfate, and tested for expression of factor IX. A construct with the factor IX cDNA under direct control by long terminal repeat gave the highest level of expression as quantitated by immunoassays as well as clotting activity assays. A single RNA transcript of 4.4 kilobases predicted by the construct and a recombinant factor IX were found. The recombinant human factor IX produced showed full clotting activity, demonstrating that CECs have an efficient mechanism for posttranslational modifications, including {gamma}-carboxylation, essential for its biological activity. These results, in addition to other properties of the endothelium, including large number of cells, accessibility, and direct contact with the circulating blood, suggest that CECs can serve as an efficient drug delivery vehicle producing factor IX in a somatic gene therapy for hemophilia B.

  8. Use of proteomics for validation of the isolation process of clotting factor IX from human plasma.

    PubMed

    Clifton, James; Huang, Feilei; Gaso-Sokac, Dajana; Brilliant, Kate; Hixson, Douglas; Josic, Djuro

    2010-01-03

    The use of proteomic techniques in the monitoring of different production steps of plasma-derived clotting factor IX (pd F IX) was demonstrated. The first step, solid-phase extraction with a weak anion-exchange resin, fractionates the bulk of human serum albumin (HSA), immunoglobulin G, and other non-binding proteins from F IX. The proteins that strongly bind to the anion-exchange resin are eluted by higher salt concentrations. In the second step, anion-exchange chromatography, residual HSA, some proteases and other contaminating proteins are separated. In the last chromatographic step, affinity chromatography with immobilized heparin, the majority of the residual impurities are removed. However, some contaminating proteins still remain in the eluate from the affinity column. The next step in the production process, virus filtration, is also an efficient step for the removal of residual impurities, mainly high molecular weight proteins, such as vitronectin and inter-alpha inhibitor proteins. In each production step, the active component, pd F IX and contaminating proteins are monitored by biochemical and immunochemical methods and by LC-MS/MS and their removal documented. Our methodology is very helpful for further process optimization, rapid identification of target proteins with relatively low abundance, and for the design of subsequent steps for their removal or purification.

  9. Factor IX Amagasaki: A new mutation in the catalytic domain resulting in the loss of both coagulant and esterase activities

    SciTech Connect

    Miyata, Toshiyuki; Iwanaga, Sadaaki ); Sakai, Toshiyuki; Sugimoto, Mitsuhiko; Naka, Hiroyuki; Yamamoto, Kazukuni; Yoshioka, Akira; Fukui, Hiromu ); Mitsui, Kotoko; Kamiya, Kensyu; Umeyama, Hideaki )

    1991-11-26

    Factor IX Amagasaki (AMG) is a naturally occurring mutant of factor IX having essentially no coagulant activity, even though normal levels of antigen are detected in plasma. Factor IX AMG was purified from the patient's plasma by immunoaffinity chromatography with an anti-factor IX monoclonal antibody column. Factor IX AMG was cleaved normally by factor VIIa-tissue factor complex, yielding a two-chain factor IXa. Amino acid composition and sequence analysis of one of the tryptic peptides isolated from factor IX AMG revealed that Gly-311 had been replaced by Glu. The authors identified a one-base substitution of guanine to adenine in exon VIII by amplifying exon VIII using the polymerase chain reaction method and sequencing the product. This base mutation also supported the replacement of Gly-311 by Glu. In the purified system, factor IXa AMG did not activate for factor X in the presence of factor VIII, phospholipids, and Ca{sup 2+}, and no esterase activity toward Z-Arg-p-nitrobenzyl ester was observed. The model building of the serine protease domain of factor IXa suggests that the Gly-311 {yields} Glu exchange would disrupt the specific conformational state in the active site environment, resulting in the substrate binding site not forming properly. This is the first report to show the experimental evidence for importance of a highly conserved Gly-142 (chymotrypsinogen numbering) located in the catalytic site of mammalian serine proteases so far known.

  10. In Vivo Gene Therapy of Hemophilia B: Sustained Partial Correction in Factor IX-Deficient Dogs

    NASA Astrophysics Data System (ADS)

    Kay, Mark A.; Rothenberg, Steven; Landen, Charles N.; Bellinger, Dwight A.; Leland, Frances; Toman, Carol; Finegold, Milton; Thompson, Arthur R.; Read, M. S.; Brinkhous, Kenneth M.; Woo, Savio L. C.

    1993-10-01

    The liver represents a model organ for gene therapy. A method has been developed for hepatic gene transfer in vivo by the direct infusion of recombinant retroviral vectors into the portal vasculature, which results in the persistent expression of exogenous genes. To determine if these technologies are applicable for the treatment of hemophilia B patients, preclinical efficacy studies were done in a hemophilia B dog model. When the canine factor IX complementary DNA was transduced directly into the hepatocytes of affected dogs in vivo, the animals constitutively expressed low levels of canine factor IX for more than 5 months. Persistent expression of the clotting. factor resulted in reductions of whole blood clotting and partial thromboplastin times of the treated animals. Thus, long-term treatment of hemophilia B patients may be feasible by direct hepatic gene therapy in vivo.

  11. Molecular Analysis of Factor VIII and Factor IX Genes in Hemophilia Patients: Identification of Novel Mutations and Molecular Dynamics Studies

    PubMed Central

    Al-Allaf, Faisal A.; Taher, Mohiuddin M.; Abduljaleel, Zainularifeen; Bouazzaoui, Abdellatif; Athar, Mohammed; Bogari, Neda M.; Abalkhail, Halah A.; Owaidah, Tarek MA.

    2017-01-01

    Background Hemophilias A and B are X-linked bleeding disorders caused by mutations in the factor VIII and factor IX genes, respectively. Our objective was to identify the spectrum of mutations of the factor VIII and factor IX genes in Saudi Arabian population and determine the genotype and phenotype correlations by molecular dynamics (MD) simulation. Methods For genotyping, blood samples from Saudi Arabian patients were collected, and the genomic DNA was amplified, and then sequenced by Sanger method. For molecular simulations, we have used softwares such as CHARMM (Chemistry at Harvard Macromolecular Mechanics; http://www.charmm-gui.org) and GROMACS. In addition, the secondary structure was determined based on the solvent accessibility for the confirmation of the protein stability at the site of mutation. Results Six mutations (three novel and three known) were identified in factor VIII gene, and six mutations (one novel and five known) were identified in factor IX gene. The factor VIII novel mutations identified were c.99G>T, p. (W33C) in exon 1, c.2138 DelA, p. (N713Tfs*9) in eon14, also a novel mutation at splicing acceptor site of exon 23 c.6430 - 1G>A. In factor IX, we found a novel mutation c.855G>C, p. (E285D) in exon 8. These novel mutations were not reported in any factor VIII or factor IX databases previously. The deleterious effects of these novel mutations were confirmed by PolyPhen2 and SIFT programs. Conclusion The protein functional and structural studies and the models built in this work would be appropriate for predicting the effects of deleterious amino acid substitutions causing these genetic disorders. These findings are useful for genetic counseling in the case of consanguineous marriages which is more common in the Saudi Arabia. PMID:28270892

  12. Ares I-X Flight Test Development Challenges and Success Factors

    NASA Technical Reports Server (NTRS)

    Askins, Bruce; Davis, Steve; Olsen, Ronald; Taylor, James

    2010-01-01

    The NASA Constellation Program's Ares I-X rocket launched successfully on October 28, 2009 collecting valuable data and providing risk reduction for the Ares I project. The Ares I-X mission was formulated and implemented in less than four years commencing with the Exploration Systems Architecture Study in 2005. The test configuration was founded upon assets and processes from other rocket programs including Space Shuttle, Atlas, and Peacekeeper. For example, the test vehicle's propulsion element was a Shuttle Solid Rocket Motor. The Ares I-X rocket comprised a motor assembly, mass and outer mold line simulators of the Ares I Upper Stage, Orion Spacecraft and Launch Abort System, a roll control system, avionics, and other miscellaneous components. The vehicle was 327 feet tall and weighed approximately 1,800,000 pounds. During flight the rocket reached a maximum speed of Mach 4.8 and an altitude of 150,000 feet. The vehicle demonstrated staging at 130,000 feet, tested parachutes for recovery of the motor, and utilized approximately 900 sensors for data collection. Developing a new launch system and preparing for a safe flight presented many challenges. Specific challenges included designing a system to withstand the environments, manufacturing large structures, and re-qualifying heritage hardware. These and other challenges, if not mitigated, may have resulted in test cancellation. Ares I-X succeeded because the mission was founded on carefully derived objectives, led by decisive and flexible management, implemented by an exceptionally talented and dedicated workforce, and supported by a thorough independent review team. Other major success factors include the use of proven heritage hardware, a robust System Integration Laboratory, multi-NASA center and contractor team, concurrent operations, efficient vehicle assembly, effective risk management, and decentralized element development with a centralized control board. Ares I-X was a technically complex test that

  13. Recent developments in high purity niobium metal production at CBMM

    SciTech Connect

    Abdo, Gustavo Giovanni Ribeiro Sousa, Clovis Antonio de Faria Guimarães, Rogério Contato Ribas, Rogério Marques Vieira, Alaércio Salvador Martins Menezes, Andréia Duarte Fridman, Daniel Pallos Cruz, Edmundo Burgos

    2015-12-04

    CBMM is a global supplier of high quality niobium products including pure niobium, the focus of this paper. CBMM’s position has been consolidated over three decades of producing high purity niobium metal ingots. The company supplies, among other products, commercial and reactor grade niobium ingots. One of the main uses of CBMM’s ingots is for the manufacture of particle accelerators (superconducting radio frequency – SRF – cavities), where the purity and homogeneity of niobium metal is essentially important for good performance. CBMM constantly strives to improve process controls and product quality, and is currently implementing innovations in production, research and development to further improve ingot quality. The main aim is to reduce the content of interstitial elements, such as nitrogen (N), oxygen (O), carbon (C), and hydrogen (H), starting with the raw materials through the final step of ingot production. CBMM held the first trial to produce the world’s largest-diameter niobium ingot (as cast 535 mm). The results of this initial trial presented very low levels of interstitial impurities (N, O, C, H), allowing the achievement of residual resistivity ratio (RRR) values very close to 300 in a six-melt process in an electron beam furnace. These values were reached with 850 ppm of tantalum. SRF cavities will be produced with this material in order to study the effect of low impurities and high RRR on the Q factor and accelerating gradient.

  14. Recent developments in high purity niobium metal production at CBMM

    NASA Astrophysics Data System (ADS)

    Abdo, Gustavo Giovanni Ribeiro; Sousa, Clovis Antonio de Faria; Guimarães, Rogério Contato; Ribas, Rogério Marques; Vieira, Alaércio Salvador Martins; Menezes, Andréia Duarte; Fridman, Daniel Pallos; Cruz, Edmundo Burgos

    2015-12-01

    CBMM is a global supplier of high quality niobium products including pure niobium, the focus of this paper. CBMM's position has been consolidated over three decades of producing high purity niobium metal ingots. The company supplies, among other products, commercial and reactor grade niobium ingots. One of the main uses of CBMM's ingots is for the manufacture of particle accelerators (superconducting radio frequency - SRF - cavities), where the purity and homogeneity of niobium metal is essentially important for good performance. CBMM constantly strives to improve process controls and product quality, and is currently implementing innovations in production, research and development to further improve ingot quality. The main aim is to reduce the content of interstitial elements, such as nitrogen (N), oxygen (O), carbon (C), and hydrogen (H), starting with the raw materials through the final step of ingot production. CBMM held the first trial to produce the world's largest-diameter niobium ingot (as cast 535 mm). The results of this initial trial presented very low levels of interstitial impurities (N, O, C, H), allowing the achievement of residual resistivity ratio (RRR) values very close to 300 in a six-melt process in an electron beam furnace. These values were reached with 850 ppm of tantalum. SRF cavities will be produced with this material in order to study the effect of low impurities and high RRR on the Q factor and accelerating gradient.

  15. High-purity silica reflecting heat shield development

    NASA Technical Reports Server (NTRS)

    Congdon, W. M.

    1974-01-01

    A high-purity, fused-silica reflecting heat shield for the thermal protection of outer-planet probes was developed. Factors that strongly influence the performance of a silica heat shield were studied. Silica-bonded silica configurations, each prepared by a different technique, were investigated and rated according to its relative merits. Slip-casting was selected as the preferred fabrication method because it produced good reflectivity and good strength, and is relatively easy to scale up for a full-size outer-planet probe. The slips were cast using a variety of different particle sizes: continuous particle-size slips; monodisperse particle-size slips; and blends of monodisperse particle-size slips were studied. In general, smaller particles gave the highest reflectance. The monodisperse slips as well as the blend slips gave a higher reflectance than the continuous particle-size slips. An upgraded and fused natural quartz was used to study the effects of microstructure on reflectance and as the baseline to ascertain the increase in reflectance obtained from using a higher-purity synthetic material.

  16. Relation of factor VIII and IX inhibitors with ABO blood groups in 150 patients with haemophilia A and B.

    PubMed

    Torghabeh, Hassan Mansouri; Pourfathollah, Aliakbar; Shooshtari, Mahmood Mahmoodian; Yazdi, Zahra Rezaie

    2006-03-01

    Many investigations have proved relations between ABO blood groups with some diseases and factor VIII and von willebrand level in plasma. In this study we investigated a relation between ABO blood groups and factor VIII and IX inhibitors in 102 patients with haemophilia A and 48 patients with haemophilia B. The assay of inhibitor was done by Bethesda method. There were no relation between ABO blood groups and factor VIII and IX inhibitors.

  17. Pharmacokinetics, thrombogenicity and safety of a double viral inactivated factor IX concentrate compared with a prothrombin complex concentrate.

    PubMed

    Ruiz-Sáez, A; Hong, A; Arguello, A; Echenagucia, M; Boadas, A; Fabbrizzi, F; Minichilli, F; Bosch, N B

    2005-11-01

    Therapeutic options for developing countries have to assure an optimum safety and efficacy and low-cost antihaemophilic concentrates. A single blind randomized crossover study was carried out in 12 previously treated HB patients, comparing the pharmacokinetics (PK), thrombogenicity (TG) and safety of two plasma-derived double-inactivated (solvent/detergent heating at 100 degrees C, 30 min) factor IX (FIX) concentrates, UMAN COMPLEX DI (product A) [plasma-derived prothrombin concentrates (PCC)] and a high purity FIX concentrate AIMAFIX DI (product B, HPFIX). In a non-bleeding state, they received one single intravenous dose 50 IU FIX kg(-1) of PCC or HPFIX, and after a wash-out period of 14 days, the other product. We evaluated acute tolerance and determined PK parameters based on FIX levels measured over a 50 h postinfusion period. We studied fibrinogen, platelets, antithrombin, F1 + 2, TAT, D-dimer, over a 360 min postinfusion period. Ten cases remained in on-demand treatment for 6 months, five with PCC and five with HPFIX. PK and anti-FIX inhibitors were repeated at 3 and 6 months. No inhibitors were detected. PK values (PCC vs. HPFIX): clearence (CL; mL h(-1) kg(-1)) 5.2 +/- 1.4 vs. 6.5 +/- 1.4; the volume of distribution at steady state (mL kg(-1)) 154.9 +/- 54.9 vs. 197.5 +/- 72.5; mean residence time (h) 29.7 +/- 8.1 vs. 30.7 +/- 9.2; T(1/2) (h) 22.3 +/- 7 vs. 23.5 +/- 12.3; incremental recovery (IR; U dL(-1) U(-1) kg(-1)) 0.96 +/- 0.17 vs. 0.76 +/- 0.13. HPFIX showed significant lower IR and higher CL. There were no differences in PK at 3 and 6 months. In TG, significant increments in TAT and F1 + 2 at 30 min and 6 h were found with PCC. Product B PK results agrees with reported results for other HPFIX preparations. Use of PCC product A has to consider its thrombogenic activity.

  18. Factor Activity Assays for Monitoring Extended Half-Life FVIII and Factor IX Replacement Therapies.

    PubMed

    Kitchen, Steve; Tiefenbacher, Stefan; Gosselin, Robert

    2017-04-01

    The advent of modified factor VIII (FVIII) and factor IX (FIX) molecules with extended half-lives (EHLs) compared with native FVIII and FIX represents a major advance in the field of hemophilia care, with the potential to reduce the frequency of prophylactic injections and/or to increase the trough level prior to subsequent injections. Monitoring treatment through laboratory assays will be an important part of ensuring patient safety, including any tailoring of prophylaxis. Several approaches have been used to extend half-lives, including PEGylation, and fusion to albumin or immunoglobulin. Some of these modifications affect factor assays as routinely performed in hemophilia centers; so, laboratories will need to use FVIII and FIX assays which have been shown to be suitable on a product-by-product basis. For some products, there are marked differences between results obtained using one-stage or chromogenic assays and results obtained using different reagents in the one-stage assay. The laboratory should use an assay in which the recovery of the product closely aligns with the assay used by the pharmaceutical company to assign potency to the product, so that the units reported by the laboratory agree with those used to demonstrate efficacy of the product during clinical trials. Reported assay differences in relation to several of the EHL FVIII and FIX molecules will be reviewed in this article.

  19. Luminescence and photoconductivity of high-purity cadmium selenide

    SciTech Connect

    Martynov, V.N.

    1995-10-01

    Slightly off-stoichlometric high-purity cadmium and zinc chalcogenides are used as high-efficiency sensors in various optoelectronic devices. The procedure for preparing high-purity chalcogenides was described elsewhere. Such materials (wurtzite-type structure, sp. gr. C{sup 4}{sub 6v}) exhibit exciton luminescence and the photoconductivity associated with the A-, B-, and C-excitonic series over a wide temperature range. In this work, we studied the luminescence and photoconductivity (PC) of cadmium selenide prepared as described.

  20. The prevalence of factor VIII and IX inhibitors among Saudi patients with hemophilia

    PubMed Central

    Owaidah, Tarek; Momen, Abdulkareem Al; Alzahrani, Hazzaa; Almusa, Abdulrahman; Alkasim, Fawaz; Tarawah, Ahmed; Nouno, Randa Al; Batniji, Fatima Al; Alothman, Fahad; Alomari, Ali; Abu-Herbish, Saud; Abu-Riash, Mahmoud; Siddiqui, Khawar; Ahmed, Mansor; Mohamed, SY; Saleh, Mahasen

    2017-01-01

    Abstract Hemophilia A and B are X-linked diseases that predominantly affect male patients. Patients can develop coagulation factor inhibitors, which exponentially increases the treatment cost. However, the prevalence of factor VIII and IX inhibitors in Saudi Arabia is unclear. This study aimed to determine the Saudi prevalence of factor VIII and IX inhibitors. This 4-year, 7-center, cross-sectional study evaluated the Saudi prevalences of hemophilia A and B. We collected the patients’ clinical data, evaluated their disease, and tested for factor inhibitors. We included 202 patients with hemophilia (median age at diagnosis: 0.13 years, range: birth–34.8 years). The patients included 198 male patients (98%), 148 patients with hemophilia A (73.3%), and 54 patients with hemophilia B (26.7%). The patients exhibited severe factor VIII activity (<1%; 121 patients; 5.2%), moderate activity (1–5%; 7 patients; 4.9%), and mild activity (14 patients; 9.9%). Among the patients with care-related data, most patients were treated for episodic bleeding (76.8%) or received prophylaxis (22.6%); 1 patient received both treatments. Among the patients with source-related data, the factor replacements were derived from plasma (48.4%), recombinant concentrates (22.9%), both sources (14.6%), or fresh frozen plasma (14.1%). Factor VIII inhibitors were observed in 43 (29.3%) of the 147 patients, and only 1 of the 54 patients developed factor IX inhibitors. Most patients who developed inhibitors had severe hemophilia (40/44; 90.9%), and inhibitors were also common among patients who received recombinant products (14/43; 32.6%). The Saudi prevalence of factor inhibitors was similar to those among other ethnic populations. PMID:28079788

  1. Preparation of high purity copper fluoride by fluorinating copper hydroxyfluoride

    NASA Technical Reports Server (NTRS)

    King, R. B.; Lundquist, J. R.

    1969-01-01

    Copper fluoride containing no more than 50 ppm of any contaminating element was prepared by the fluorination of copper hydroxyfluoride. The impurity content was obtained by spark source mass spectrometry. High purity copper fluoride is needed as a cathode material for high energy density batteries.

  2. Electrochemical study of aluminum corrosion in boiling high purity water

    NASA Technical Reports Server (NTRS)

    Draley, J. E.; Legault, R. A.

    1969-01-01

    Electrochemical study of aluminum corrosion in boiling high-purity water includes an equation relating current and electrochemical potential derived on the basis of a physical model of the corrosion process. The work involved an examination of the cathodic polarization behavior of 1100 aluminum during aqueous oxidation.

  3. Low cost routes to high purity silicon and derivatives thereof

    DOEpatents

    Laine, Richard M; Krug, David James; Marchal, Julien Claudius; Mccolm, Andrew Stewart

    2013-07-02

    The present invention is directed to a method for providing an agricultural waste product having amorphous silica, carbon, and impurities; extracting from the agricultural waste product an amount of the impurities; changing the ratio of carbon to silica; and reducing the silica to a high purity silicon (e.g., to photovoltaic silicon).

  4. Hemophilia as a defect of the tissue factor pathway of blood coagulation: Effect of factors VIII and IX on factor X activation in a continuous-flow reactor

    SciTech Connect

    Repke, D.; Gemmell, C.H.; Guha, A.; Turitto, V.T.; Nemerson, Y. ); Broze, G.J. Jr. )

    1990-10-01

    The effect of factors VIII and IX on the ability of the tissue factor-factor VIIa complex to activate factor X was studied in a continuous-flow tubular enzyme reactor. Tissue factor immobilized in a phospholipid bilayer on the inner surface of the tube was exposed to a perfusate containing factors VIIa, VIII, IX, and X flowing at a wall shear rate of 57, 300, or 1130 sec{sup {minus}1}. The addition of factors VIII and IX at their respective plasma concentrations resulted in a further 2{endash}-to 3{endash}fold increase. The direct activation of factor X by tissue factor-factor VIIa could be virtually eliminated by the lipoprotein-associated coagulation inhibitor. These results suggest that the tissue factor pathway, mediated through factors VIII and IX, produces significant levels of factor Xa even in the presence of an inhibitor of the tissue factor-factor VIIa complex; moreover, the activation is dependent on local shear conditions. These findings are consistent both with a model of blood coagulation in which initiation of the system results from tissue factor and with the bleeding observed in hemophilia.

  5. The rates and patterns of deletions in the human factor IX gene

    SciTech Connect

    Ketterling, R.P.; Vielhaber, E.L.; Lind, T.J.; Thorland, E.C.; Sommer S.S. )

    1994-02-01

    Deletions are commonly observed in genes with either segments of highly homologous sequences or excessive gene length. However, in the factor IX gene and in most genes, deletions (of [ge]21 bp) are uncommon. The authors have analyzed DNA from 290 families with hemophilia B (203 independent mutations) and have found 12 deletions >20 bp. Eleven of these are >2 kb (range >3-163 kb), and one is 1.1 kb. The junctions of the four deletions that are completely contained within the factor IX gene have been determined. A novel mutation occurred in patient HB128: the data suggest that a 26.8-kb deletion occurred between two segments of alternating purines and pyrimidines and that a 2.3-kb sense strand segment derived from the deleted region was inserted. For a sample of 203 independent mutations, the authors estimate the [open quotes]baseline[close quotes] rates of deletional mutation per base pair per generation as a function of size. The rate for large (>2 kb)I deletions is exceedingly low. For every mutational event in which a given base is at the junction of a large deletion, there are an estimated 58 microdeletions (<20 bp) and 985 single-base substitutions at that base. Analysis of the nine reported deletion junctions in the factor IX gene literature reveals that (i) five are associated with inversion, orphan sequences, or sense strand insertions; (ii) four are simple deletions that display an excess of short direct repeats at their junctions; (iii) there is no dramatic clustering of junctions within the gene; and (iv) with the exception of alternating purines and pyrimidines, deletion junctions are not preferentially associated with repetitive DNA. 58 refs., 5 figs., 5 tabs.

  6. Systemic delivery of factor IX messenger RNA for protein replacement therapy.

    PubMed

    Ramaswamy, Suvasini; Tonnu, Nina; Tachikawa, Kiyoshi; Limphong, Pattraranee; Vega, Jerel B; Karmali, Priya P; Chivukula, Pad; Verma, Inder M

    2017-03-07

    Safe and efficient delivery of messenger RNAs for protein replacement therapies offers great promise but remains challenging. In this report, we demonstrate systemic, in vivo, nonviral mRNA delivery through lipid nanoparticles (LNPs) to treat a Factor IX (FIX)-deficient mouse model of hemophilia B. Delivery of human FIX (hFIX) mRNA encapsulated in our LUNAR LNPs results in a rapid pulse of FIX protein (within 4-6 h) that remains stable for up to 4-6 d and is therapeutically effective, like the recombinant human factor IX protein (rhFIX) that is the current standard of care. Extensive cytokine and liver enzyme profiling showed that repeated administration of the mRNA-LUNAR complex does not cause any adverse innate or adaptive immune responses in immune-competent, hemophilic mice. The levels of hFIX protein that were produced also remained consistent during repeated administrations. These results suggest that delivery of long mRNAs is a viable therapeutic alternative for many clotting disorders and for other hepatic diseases where recombinant proteins may be unaffordable or unsuitable.

  7. Systemic delivery of factor IX messenger RNA for protein replacement therapy

    PubMed Central

    Ramaswamy, Suvasini; Tonnu, Nina; Tachikawa, Kiyoshi; Limphong, Pattraranee; Vega, Jerel B.; Karmali, Priya P.; Chivukula, Pad; Verma, Inder M.

    2017-01-01

    Safe and efficient delivery of messenger RNAs for protein replacement therapies offers great promise but remains challenging. In this report, we demonstrate systemic, in vivo, nonviral mRNA delivery through lipid nanoparticles (LNPs) to treat a Factor IX (FIX)-deficient mouse model of hemophilia B. Delivery of human FIX (hFIX) mRNA encapsulated in our LUNAR LNPs results in a rapid pulse of FIX protein (within 4–6 h) that remains stable for up to 4–6 d and is therapeutically effective, like the recombinant human factor IX protein (rhFIX) that is the current standard of care. Extensive cytokine and liver enzyme profiling showed that repeated administration of the mRNA–LUNAR complex does not cause any adverse innate or adaptive immune responses in immune-competent, hemophilic mice. The levels of hFIX protein that were produced also remained consistent during repeated administrations. These results suggest that delivery of long mRNAs is a viable therapeutic alternative for many clotting disorders and for other hepatic diseases where recombinant proteins may be unaffordable or unsuitable. PMID:28202722

  8. A novel method to synthesize high purity, nanostructured copper

    SciTech Connect

    Hodge, A M; Wang, Y M; Barbee, T W

    2005-08-30

    Nanostructured high purity (99.999%) copper foils, 10 cm in diameter and 22-25 microns thick were produced using nanoscale multilayer technology. The foils were produced using five different layer thicknesses ranging from 1.25 to 43.6 nm (18,000 to 520 layers). This process delivers the ability to produce multiple large-scale samples during a single deposition run with very small residual stresses. Tensile and indentation tests demonstrate that the material produced is a high strength copper ({sigma}{sub y} {approx} 540-690 MPa).

  9. Neutron energy determination with a high-purity germanium detector

    NASA Technical Reports Server (NTRS)

    Beck, Gene A.

    1992-01-01

    Two areas that are related to planetary gamma-ray spectrometry are investigated. The first task was the investigation of gamma rays produced by high-energy charged particles and their secondaries in planetary surfaces by means of thick target bombardments. The second task was the investigation of the effects of high-energy neutrons on gamma-ray spectral features obtained with high-purity Ge-detectors. For both tasks, as a function of the funding level, the experimental work was predominantly tied to that of other researchers, whenever there was an opportunity to participate in bombardment experiments at large or small accelerators for charged particles.

  10. The GALATEA test-facility for high purity germanium detectors

    NASA Astrophysics Data System (ADS)

    Abt, I.; Caldwell, A.; Dönmez, B.; Garbini, L.; Irlbeck, S.; Majorovits, B.; Palermo, M.; Schulz, O.; Seitz, H.; Stelzer, F.

    2015-05-01

    GALATEA is a test facility designed to investigate bulk and surface effects in high purity germanium detectors. A vacuum tank houses a cold volume with the detector inside. A system of three precision motorized stages allows an almost complete scan of the detector. The main feature of GALATEA is that there is no material between source and detector. This allows the usage of alpha and beta sources to study surface effects. A 19-fold segmented true-coaxial germanium detector was used for commissioning. A first analysis of data obtained with an alpha source is presented here.

  11. Bulk and surface effects in segmented high purity germanium detectors

    NASA Astrophysics Data System (ADS)

    Abt, I.; Caldwell, A.; Dönmez, B.; Irlbeck, S.; Majorovits, B.; Volynets, O.

    2013-08-01

    Segmented high-purity germanium detectors have been developed for a variety of experiments. The segmentation is used to augment the excellent energy resolution of such a device with spatial information to disentangle event topologies. Several performance aspects of true-coaxial segmented detectors are presented, especially the effects due to the crystallographic axes and the problem of events close to the surfaces of the detector. A test stand and Monte Carlo tools developed to study such effects are introduced. The simulation tools can also be used to design novel detectors, such as segmented point-contact detectors. A particular design is presented and discussed.

  12. Oral delivery of bioencapsulated coagulation factor IX prevents inhibitor formation and fatal anaphylaxis in hemophilia B mice

    PubMed Central

    Verma, Dheeraj; Moghimi, Babak; LoDuca, Paul A.; Singh, Harminder D.; Hoffman, Brad E.; Herzog, Roland W.; Daniell, Henry

    2010-01-01

    To address complications of pathogenic antibody or life-threatening anaphylactic reactions in protein replacement therapy for patients with hemophilia or other inherited protein deficiencies, we have developed a prophylactic protocol using a murine hemophilia B model. Oral delivery of coagulation factor IX fused with cholera toxin β-subunit (with or without a furin cleavage site; CTB-FFIX or CTB-FIX), expressed in chloroplasts (up to 3.8% soluble protein or 0.4 mg/g leaf tissue), bioencapsulated in plant cells, effectively blocked formation of inhibitory antibodies (undetectable or up to 100-fold less than controls). Moreover, this treatment eliminated fatal anaphylactic reactions that occurred after four to six exposures to intravenous F.IX. Whereas only 20–25% of control animals survived after six to eight F.IX doses, 90–93% of F.IX-fed mice survived 12 injections without signs of allergy or anaphylaxis. Immunostaining confirmed delivery of F.IX to Peyer's patches in the ileum. Within 2–5 h, feeding of CTB-FFIX additionally resulted in systemic delivery of F.IX antigen. This high-responder strain of hemophilia B mice represents a new animal model to study anaphylactic reactions. The protocol was effective over a range of oral antigen doses (equivalent to 5–80 μg recombinant F.IX/kg), and controlled inhibitor formation and anaphylaxis long-term, up to 7 months (∼40% life span of this mouse strain). Oral antigen administration caused a deviant immune response that suppressed formation of IgE and inhibitory antibodies. This cost-effective and efficient approach of antigen delivery to the gut should be applicable to several genetic diseases that are prone to pathogenic antibody responses during treatment. PMID:20351275

  13. Physiological levels of blood coagulation factors IX and X control coagulation kinetics in an in vitro model of circulating tissue factor

    NASA Astrophysics Data System (ADS)

    Tormoen, Garth W.; Khader, Ayesha; Gruber, András; McCarty, Owen J. T.

    2013-06-01

    Thrombosis significantly contributes to cancer morbidity and mortality. The mechanism behind thrombosis in cancer may be circulating tissue factor (TF), as levels of circulating TF are associated with thrombosis. However, circulating TF antigen level alone has failed to predict thrombosis in patients with cancer. We hypothesize that coagulation factor levels regulate the kinetics of circulating TF-induced thrombosis. Coagulation kinetics were measured as a function of individual coagulation factor levels and TF particle concentration. Clotting times increased when pooled plasma was mixed at or above a ratio of 4:6 with PBS. Clotting times increased when pooled plasma was mixed at or above a ratio of 8:2 with factor VII-depleted plasma, 7:3 with factor IX- or factor X-depleted plasmas, or 2:8 with factor II-, V- or VIII-depleted plasmas. Addition of coagulation factors VII, X, IX, V and II to depleted plasmas shortened clotting and enzyme initiation times, and increased enzyme generation rates in a concentration-dependent manner. Only additions of factors IX and X from low-normal to high-normal levels shortened clotting times and increased enzyme generation rates. Our results demonstrate that coagulation kinetics for TF particles are controlled by factor IX and X levels within the normal physiological range. We hypothesize that individual patient factor IX and X levels may be prognostic for susceptibility to circulating TF-induced thrombosis.

  14. Survey of the anti-factor IX immunoglobulin profiles in patients with hemophilia B using a fluorescence-based immunoassay.

    PubMed

    Boylan, B; Rice, A S; Neff, A T; Manco-Johnson, M J; Kempton, C L; Miller, C H

    2016-10-01

    Essentials Studies characterizing neutralizing antibodies (inhibitors) in hemophilia B (HB) are lacking. The current study describes anti-factor (F) IX antibody profiles in 37 patients who have HB. Anti-FIX IgG4 levels exhibited a strong positive correlation with Nijmegen-Bethesda results. These data will help to more clearly define, predict, and treat alloantibody formation in HB.

  15. Springback in Deep Drawn High Purity Niobium for Superconductor Cavities

    SciTech Connect

    Ganapati Rao Myneni; Peter Kneisel

    2005-09-01

    Superconducting radio frequency (SRF) cavities made from deep drawn high-purity niobium have become a popular approach for the design of particle accelerators. A number of current accelerators use this technology and it is a leading candidate for future designs. The development of this technology has required significant advances in many scientific fields including metallurgy, high vacuum physics, surface science, and forming. Recently proposed modifications to the current process for fabrication of these cavities has resulted in increased concern about the distribution of deformation, residual stress patterns, and springback. This presentation will report on the findings of a recently initiated program to study plastic flow and springback in the fabrication of these cavities and the influence of metallurgical variables including grain size and impurity content.

  16. Study on the Properties of High Purity Germanium Crystals

    NASA Astrophysics Data System (ADS)

    Yang, G.; Mei, H.; Guan, Y. T.; Wang, G. J.; Mei, D. M.; Irmscher, K.

    2015-05-01

    In the crystal growth lab of South Dakota University, we are growing high purity germanium (HPGe) crystals and using the grown crystals to make radiation detectors. As the detector grade HPGe crystals, they have to meet two critical requirements: an impurity level of ∼109 to 10 atoms /cm3 and a dislocation density in the range of ∼102 to 104 / cm3. In the present work, we have used the following four characterization techniques to investigate the properties of the grown crystals. First of all, an x-ray diffraction method was used to determine crystal orientation. Secondly, the van der Pauw Hall effect measurement was used to measure the electrical properties. Thirdly, a photo-thermal ionization spectroscopy (PTIS) was used to identify what the impurity atoms are in the crystal. Lastly, an optical microscope observation was used to measure dislocation density in the crystal. All of these characterization techniques have provided great helps to our crystal activities.

  17. Secondary emission conductivity of high purity silica fabric

    NASA Technical Reports Server (NTRS)

    Belanger, V. J.; Eagles, A. E.

    1977-01-01

    High purity silica fabrics were proposed for use as a material to control the effects of electrostatic charging of satellites at synchronous altitudes. These materials exhibited very quiet behavior when placed in simulated charging environments as opposed to other dielectrics used for passive thermal control which exhibit varying degrees of electrical arcing. Secondary emission conductivity is proposed as a mechanism for this superior behavior. Design of experiments to measure this phenomena and data taken on silica fabrics are discussed as they relate to electrostatic discharge (ESD) control on geosynchronous orbit spacecraft. Studies include the apparent change in resistivity of the material as a function of the electron beam energy, flux intensity, and the effect of varying electric fields impressed across the material under test.

  18. Precipitation of hydrides in high purity niobium after different treatments

    SciTech Connect

    Barkov, F.; Romanenko, A.; Trenikhina, Y.; Grassellino, A.

    2013-01-01

    Precipitation of lossy non-superconducting niobium hydrides represents a known problem for high purity niobium in superconducting applications. Using cryogenic optical and laser confocal scanning microscopy we have directly observed surface precipitation and evolution of niobium hydrides in samples after different treatments used for superconducting RF cavities for particle acceleration. Precipitation is shown to occur throughout the sample volume, and the growth of hydrides is well described by the fast diffusion-controlled process in which almost all hydrogen is precipitated at $T=140$~K within $\\sim30$~min. 120$^{\\circ}$C baking and mechanical deformation are found to affect hydride precipitation through their influence on the number of nucleation and trapping centers.

  19. Effective gene therapy for haemophilic mice with pathogenic factor IX antibodies.

    PubMed

    Markusic, David M; Hoffman, Brad E; Perrin, George Q; Nayak, Sushrusha; Wang, Xiaomei; LoDuca, Paul A; High, Katherine A; Herzog, Roland W

    2013-11-01

    Formation of pathogenic antibodies is a major problem in replacement therapies for inherited protein deficiencies. For example, antibodies to coagulation factors ('inhibitors') seriously complicate treatment of haemophilia. While immune tolerance induction (ITI) protocols have been developed, inhibitors against factor IX (FIX) are difficult to eradicate due to anaphylactic reactions and nephrotic syndrome and thus substantially elevate risks for morbidity and mortality. However, hepatic gene transfer with an adeno-associated virus (AAV) serotype 8 vector expressing FIX (at levels of ≥4% of normal) rapidly reversed pre-existing high-titre inhibitors in haemophilia B mice, eliminated antibody production by B cells, desensitized from anaphylaxis (even if protein therapy was resumed) and provided long-term correction. High levels of FIX protein suppressed memory B cells and increased Treg induction, indicating direct and indirect mechanisms of suppression of inhibitor formation. Persistent presence of Treg was required to prevent relapse of antibodies. Together, these data suggest that hepatic gene transfer-based ITI provides a safe and effective alternative to eradicate inhibitors. This strategy may be broadly applicable to reversal of antibodies in different genetic diseases.

  20. Automation of the Characterization of High Purity Germanium Detectors

    NASA Astrophysics Data System (ADS)

    Dugger, Charles ``Chip''

    2014-09-01

    Neutrinoless double beta decay is a rare hypothesized process that may yield valuable insight into the fundamental properties of the neutrino. Currently there are several experiments trying to observe this process, including the Majorana DEMONSTRAOR experiment, which uses high purity germanium (HPGe) detectors to generate and search for these events. Because the event happens internally, it is essential to have the lowest background possible. This is done through passive detector shielding, as well as event discrimination techniques that distinguish between multi-site events characteristic of gamma-radiation, and single-site events characteristic of neutrinoless double beta decay. Before fielding such an experiment, the radiation response of the detectors must be characterized. A robotic arm is being tested for future calibration of HPGe detectors. The arm will hold a source at locations relative to the crystal while data is acquired. Several radioactive sources of varying energy levels will be used to determine the characteristics of the crystal. In this poster, I will present our work with the robot, as well as the characterization of data we took with an underground HPGe detector at the WIPP facility in Carlsbad, NM (2013). Neutrinoless double beta decay is a rare hypothesized process that may yield valuable insight into the fundamental properties of the neutrino. Currently there are several experiments trying to observe this process, including the Majorana DEMONSTRAOR experiment, which uses high purity germanium (HPGe) detectors to generate and search for these events. Because the event happens internally, it is essential to have the lowest background possible. This is done through passive detector shielding, as well as event discrimination techniques that distinguish between multi-site events characteristic of gamma-radiation, and single-site events characteristic of neutrinoless double beta decay. Before fielding such an experiment, the radiation response of

  1. Factor IXMadrid 2: a deletion/insertion in factor IX gene which abolishes the sequence of the donor junction at the exon IV-intron d splice site.

    PubMed Central

    Solera, J; Magallón, M; Martin-Villar, J; Coloma, A

    1992-01-01

    DNA from a patient with severe hemophilia B was evaluated by RFLP analysis, producing results which suggested the existence of a partial deletion within the factor IX gene. The deletion was further localized and characterized by PCR amplification and sequencing. The altered allele has a 4,442-bp deletion which removes both the donor splice site located at the 5' end of intron d and the two last coding nucleotides located at the 3' end of exon IV in the normal factor IX gene; this fragment has been replaced by a 47-bp sequence from the normal factor IX gene, although this fragment has been inserted in inverted orientation. Two homologous sequences have been discovered at the ends of the deleted DNA fragment. Images Figure 1 PMID:1346483

  2. Factor IXMadrid 2: a deletion/insertion in factor IX gene which abolishes the sequence of the donor junction at the exon IV-intron d splice site.

    PubMed

    Solera, J; Magallón, M; Martin-Villar, J; Coloma, A

    1992-02-01

    DNA from a patient with severe hemophilia B was evaluated by RFLP analysis, producing results which suggested the existence of a partial deletion within the factor IX gene. The deletion was further localized and characterized by PCR amplification and sequencing. The altered allele has a 4,442-bp deletion which removes both the donor splice site located at the 5' end of intron d and the two last coding nucleotides located at the 3' end of exon IV in the normal factor IX gene; this fragment has been replaced by a 47-bp sequence from the normal factor IX gene, although this fragment has been inserted in inverted orientation. Two homologous sequences have been discovered at the ends of the deleted DNA fragment.

  3. Factor IX[sub Madrid 2]: A deletion/insertion in Facotr IX gene which abolishes the sequence of the donor junction at the exon IV-intron d splice site

    SciTech Connect

    Solera, J. ); Magallon, M.; Martin-Villar, J. ); Coloma, A. )

    1992-02-01

    DNA from a patient with severe hemophilia B was evaluated by RFLP analysis, producing results which suggested the existence of a partial deletion within the factor IX gene. The deletion was further localized and characterized by PCR amplification and sequencing. The altered allele has a 4,442-bp deletion which removes both the donor splice site located at the 5[prime] end of intron d and the two last coding nucleotides located at the 3[prime] end of exon IV in the normal factor IX gene; this fragment has been inserted in inverted orientation. Two homologous sequences have been discovered at the ends of the deleted DNA fragment.

  4. Permeation of oxygen through high purity, large grain silver

    NASA Technical Reports Server (NTRS)

    Outlaw, R. A.; Peregoy, W. K.; Hoflund, Gar B.

    1987-01-01

    The permeation of high purity, large grain Ag membranes by oxygen has been studied over the temperature range 400 to 800 C. The permeability was found to be quite linear and repeatable, but the magnitude was 3.2 times smaller than that determined by past research. Since previous investigators studied substantially less pure Ag and conducted experiments within much poorer vacuum environments (which indicates that their grain boundary density was much greater), the data presented here suggest oxygen transport through the membrane is primarily by grain boundary diffusion. The diffusivity measurements were found to exhibit two distinct linear regions, one above and one below a critical temperature of 630 C. The high-temperature data have an activation energy (11.1 kcal/mole) similar to that reported by others, but the low-temperature data have a higher activation energy (15.3 kcal/mole), which can be explained by impurity trapping in the grain boundaries. Vacuum desorption of the oxygen-saturated Ag was found to occur at a threshold of 630 C, which is consistent with the onset of increased mobility within the grain boundaries.

  5. PERFORMANCES OF HIGH PURITY NIOBIUM CAVITIES WITH DIFFERENT GRAIN SIZES

    SciTech Connect

    Gianluigi Ciovati; Peter Kneisel; Ganapati Myneni; Swapan Chattopadhyay

    2006-08-21

    Grain boundaries have for some time been suspected of influencing the performance of RF cavities made from high purity niobium by limiting the temperature dependent BCS surface resistance to a residual resistance because of impurity segregation and by causing field limitations due to flux penetration. We have carried out a comparative study of the RF behavior of 2.2 GHz TM{sub 010} cavities of identical shape, fabricated from single crystal niobium, niobium of grain sizes of the order of several cm{sup 2} and standard poly-crystalline material. All the cavities were treated with buffered chemical polishing (BCP), post-purified at 1250 ?C and ?in-situ? baked at 120 C. This contribution reports about the results of the measurements of the temperature dependence of the surface resistance Rs(T) and the Q0 vs. Eacc behavior at 2 K. From the analysis of the Rs(T) data at low RF fields material parameters such as gap value, mean free path and residual resistance could be extracted. The dependence of the Q-value on RF field was analyzed with respect to the medium field Q-slope, Q-drop at high fields and the quench fields. The best performance resulted in a breakdown field of {approx}165 mT, corresponding to an accelerating gradient of E{sub acc} {approx} 38 MV/m.

  6. PERFORMANCES OF HIGH PURITY NIOBIUM CAVITIES WITH DIFFERENT GRAIN SIZES

    SciTech Connect

    Gianluigi Ciovati; Peter Kneisel; Ganapati Myneni; Ganapati Rao Myneni; Ganapati Rao Myneni; Swapan Chattopadhyay

    2006-08-04

    Grain boundaries have for some time been suspected of influencing the performance of RF cavities made from high purity niobium by limiting the temperature dependent BCS surface resistance to a residual resistance because of impurity segregation and by causing field limitations due to flux penetration. We have carried out a comparative study of the RF behavior of 2.2 GHz TM010 cavities of identical shape, fabricated from single crystal niobium, niobium of grain sizes of the order of several cm2 and standard poly-crystalline material. All the cavities were treated with buffered chemical polishing (BCP), post-purified at 1250 C and ''in-situ'' baked at 120 C. This contribution reports about the results of the measurements of the temperature dependence of the surface resistance Rs(T) and the Q0 vs. Eacc behavior at 2 K. From the analysis of the Rs(T) data at low RF fields material parameters such as gap value, mean free path and residual resistance could be extracted. The dependence of the Q-value on RF field was analyzed with respect to the medium field Q-slope, ''Q-drop'' at high fields and the ''quench'' fields. The best performance resulted in a breakdown field of {approx} 165 mT, corresponding to an accelerating gradient of Eacc {approx} 38 MV/m.

  7. Modified matrix volatilization setup for characterization of high purity germanium.

    PubMed

    Meruva, Adisesha Reddy; Raparthi, Shekhar; Kumar, Sunil Jai

    2016-01-01

    Modified matrix volatilization (MV) method has been described to characterize high purity germanium material of 7 N (99.99999%) purity. Transport of both, the chlorine gas generated in-situ in this method and the argon gas (carrier) is fine controlled by means of a mass flow controller. This enabled both uniform reaction of chlorine gas with the germanium matrix and smooth removal of germanium matrix as its chloride. This resulted in improvement in the reproducibility of the analytical results. The use of quartz reaction vessel has lead to the reduction in the process blank levels. The combined effect of these modifications in the MV setup has resulted in very consistent and low process blanks and hence improved detection limits of this method. Applicability of the method has been expanded to rare earth elements and other elements after examining their recoveries. The quantification is done by using inductively coupled plasma quadrupole mass spectrometer (ICP-QMS) and continuum source graphite furnace atomic absorption spectrometry (CS-GFAAS). In the absence of certified reference materials for high pure germanium, the accuracy of the method is established by spike recovery tests. The precision of the method has been found to vary from 1 to 30% for concentrations between 1 and 30 ng g(-1). The limits of detection (LOD) for the target analytes are found to be between 18 and 0.033 ng g(-1).

  8. Observing bulk diamond spin coherence in high-purity nanodiamonds

    NASA Astrophysics Data System (ADS)

    Knowles, Helena S.; Kara, Dhiren M.; Atatüre, Mete

    2014-01-01

    Nitrogen-vacancy (NV) centres in diamond are attractive for research straddling quantum information science, nanoscale magnetometry and thermometry. Whereas ultrapure bulk diamond NVs sustain the longest spin coherence times among optically accessible spins, nanodiamond NVs exhibit persistently poor spin coherence. Here we introduce high-purity nanodiamonds accommodating record-long NV coherence times, >60 μs, observed through universal dynamical decoupling. We show that the main contribution to decoherence comes from nearby nitrogen impurities rather than surface states. We protect the NV spin free precession, essential to d.c. magnetometry, by driving solely these impurities into the motional narrowing regime. This extends the NV free induction decay time from 440 ns, longer than that in type Ib bulk diamond, to 1.27 μs, which is comparable to that in type IIa (impurity-free) diamond. These properties allow the simultaneous exploitation of both high sensitivity and nanometre resolution in diamond-based emergent quantum technologies.

  9. SVA retrotransposition in exon 6 of the coagulation factor IX gene causing severe hemophilia B.

    PubMed

    Nakamura, Yuki; Murata, Moe; Takagi, Yuki; Kozuka, Toshihiro; Nakata, Yukiko; Hasebe, Ryo; Takagi, Akira; Kitazawa, Jun-ichi; Shima, Midori; Kojima, Tetsuhito

    2015-07-01

    Hemophilia B is an X-linked recessive bleeding disorder caused by abnormalities of the coagulation factor IX gene (F9). Insertion mutations in F9 ranging from a few to more than 100 base pairs account for only a few percent of all hemophilia B cases. We investigated F9 to elucidate genetic abnormalities causing severe hemophilia B in a Japanese subject. We performed PCR-mediated analysis of F9 and identified a large insertion in exon 6. Next, we carried out direct sequencing of a PCR clone of the whole insert using nested deletion by exonuclease III and S1 nuclease. We identified an approximately 2.5-kb SINE-VNTR-Alu (SVA)-F element flanked by 15-bp duplications in the antisense orientation in exon 6. Additionally, we carried out exontrap analysis to assess the effect of this retrotransposition on mRNA splicing. We observed that regular splicing at exons 5 and 6 of F9 was disturbed by the SVA retrotransposition, suggesting that abnormal FIX mRNA may be reduced by nonsense-mediated mRNA decay. In conclusion, this is the first report of SVA retrotransposition causing severe hemophilia B; only five cases of LINE-1 or Alu retrotranspositions in F9 have been reported previously.

  10. Expression of human coagulation Factor IX in transgenic tomato (Lycopersicon esculentum).

    PubMed

    Zhang, Hui; Zhao, Lingxia; Chen, Yuhui; Cui, Lijie; Ren, Weiwei; Tang, Kexuan

    2007-10-01

    In the present study, a plant binary expression vector PG-pRD12-hFIX (where PG is polygalacturonase) harbouring the hFIX (human coagulation Factor IX) gene was constructed and introduced into tomato (Lycopersicon esculentum) via Agrobacterium tumefaciens-mediated transformation. After kanamycin selection, 32 putative independent transgenic tomato plants were regenerated. PCR and Southern-blot analyses confirmed the transgenic status of some plants. RT (reverse transcription)-PCR analysis for the expression of the introduced gene (hFIX) demonstrated that the hFIX gene was expressed specifically in fruits of the tomato. Western-blot analysis confirmed the presence of a 56 kDa band specific to hFIX in the transformed tomatoes. ELISA results showed that the expression of hFIX protein reached a maximum of 15.84 ng/g fresh weight in mature fruit. A blood-clotting assay demonstrated the clotting activity of the expressed hFIX protein in transgenic tomato fruits. This is the first report on the expression of hFIX in plants, and our research provides potentially valuable knowledge for further development of the plant-derived therapeutic proteins.

  11. Once-weekly prophylactic dosing of recombinant factor IX improves adherence in hemophilia B

    PubMed Central

    Djambas Khayat, Claudia

    2016-01-01

    Regular prophylactic treatment in severe hemophilia should be considered an optimal treatment. There is no general agreement on the optimal prophylaxis regimen, and adherence to prophylaxis is a main challenge due to medical, psychosocial, and cost controversies. Improved approaches in prophylaxis regimen of hemophilia B are needed to make patients’ lives easier. There is some evidence to support the efficacy of once-weekly prophylaxis. Longer sampling schedules are required for the determination of pharmacokinetic (PK) properties of factor IX (FIX). The half-life of FIX seems to be longer than previously described and is expected to be 34 hours. The clinical significance of maintaining a 1% trough level is widely debated in hemophilia B. The overall relationship between factor concentrate levels and incidence of joint bleeding was found to be very weak. Data also indicate that the distribution of FIX into an extravascular FIX compartment may contribute to hemostasis independently of circulating plasma FIX levels. Clinical assessment of the frequency and severity of bleeds remain an important measure of the efficacy of treatment. Role of PK-guided therapy remains to be established. Two prospective randomized studies had evaluated the efficacy and safety of 100 IU/kg once-weekly prophylaxis with nonacog alfa, and this prophylaxis regimen was found to be associated with lower annual bleeding rate compared with on-demand treatment in adolescents and adults with moderately severe-to-severe hemophilia B. Secondary prophylaxis therapy with 100 IU/kg nonacog alfa once weekly reduced annual bleeding rate by 89.4% relative to on-demand treatment. Residual FIX may be supportive of effectiveness. Once-weekly prophylaxis was well tolerated in the two studies, with a safety profile similar to that reported during the on-demand treatment period. To individually tailor treatment to clinical response and to minimize costs of factor concentrate, it would be of interest to

  12. Anion-exchange purification of recombinant factor IX from cell culture supernatant using different chromatography supports.

    PubMed

    Ribeiro, Daniel A; Passos, Douglas F; Ferraz, Helen C; Castilho, Leda R

    2013-11-01

    Both recombinant and plasma-derived factor IX concentrates are used in replacement therapies for the treatment of haemophilia B. In the present work, the capture step for a recombinant FIX (rFIX) purification process was investigated. Different strong anion-exchange chromatography media (the resins Q Sepharose(®) FF and Fractogel(®) TMAE, the monolith CIM(®) QA and the membrane adsorber Sartobind(®) Q) were tested for their rFIX binding capacity under dynamic conditions. In these experiments, crude supernatant from CHO cells was used, thus in the presence of supernatant contaminants and mimicking process conditions. The highest dynamic binding capacity was obtained for the monolith, which was then further investigated. To study pseudoaffinity elution of functional rFIX with Ca(2+) ions, a design of experiments to evaluate the effects of pH, NaCl and CaCl2 on yield and purification factor was carried out. The effect of pH was not statistically significant, and a combination of no NaCl and 45mM CaCl2 yielded a good purification factor combined with a high yield of active rFIX. Under these conditions, activity yield of rFIX was higher than the mass yield, confirming selective elution of functional, γ-carboxylated rFIX. Scaling-up of this process 8 fold resulted in very similar process performance. Monitoring of the undesired activated FIX (FIXa) revealed that the FIXa/FIX ratio (1.94%) was higher in the eluate than in the loaded sample, but was still within an acceptable range. HCP and DNA clearances were high (1256 and 7182 fold, respectively), indicating that the proposed process is adequate for the intended rFIX capture step.

  13. High-purity Cu nanocrystal synthesis by a dynamic decomposition method

    NASA Astrophysics Data System (ADS)

    Jian, Xian; Cao, Yu; Chen, Guozhang; Wang, Chao; Tang, Hui; Yin, Liangjun; Luan, Chunhong; Liang, Yinglin; Jiang, Jing; Wu, Sixin; Zeng, Qing; Wang, Fei; Zhang, Chengui

    2014-12-01

    Cu nanocrystals are applied extensively in several fields, particularly in the microelectron, sensor, and catalysis. The catalytic behavior of Cu nanocrystals depends mainly on the structure and particle size. In this work, formation of high-purity Cu nanocrystals is studied using a common chemical vapor deposition precursor of cupric tartrate. This process is investigated through a combined experimental and computational approach. The decomposition kinetics is researched via differential scanning calorimetry and thermogravimetric analysis using Flynn-Wall-Ozawa, Kissinger, and Starink methods. The growth was found to be influenced by the factors of reaction temperature, protective gas, and time. And microstructural and thermal characterizations were performed by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and differential scanning calorimetry. Decomposition of cupric tartrate at different temperatures was simulated by density functional theory calculations under the generalized gradient approximation. High crystalline Cu nanocrystals without floccules were obtained from thermal decomposition of cupric tartrate at 271°C for 8 h under Ar. This general approach paves a way to controllable synthesis of Cu nanocrystals with high purity.

  14. The first EGF domain of coagulation factor IX attenuates cell adhesion and induces apoptosis.

    PubMed

    Ishikawa, Tomomi; Kitano, Hisataka; Mamiya, Atsushi; Kokubun, Shinichiro; Hidai, Chiaki

    2016-07-01

    Coagulation factor IX (FIX) is an essential plasma protein for blood coagulation. The first epidermal growth factor (EGF) motif of FIX (EGF-F9) has been reported to attenuate cell adhesion to the extracellular matrix (ECM). The purpose of the present study was to determine the effects of this motif on cell adhesion and apoptosis. Treatment with a recombinant EGF-F9 attenuated cell adhesion to the ECM within 10 min. De-adhesion assays with native FIX recombinant FIX deletion mutant proteins suggested that the de-adhesion activity of EGF-F9 requires the same process of FIX activation as that which occurs for coagulation activity. The recombinant EGF-F9 increased lactate dehydrogenase (LDH) activity release into the medium and increased the number of cells stained with annexin V and activated caspase-3, by 8.8- and 2.7-fold respectively, indicating that EGF-F9 induced apoptosis. Activated caspase-3 increased very rapidly after only 5 min of administration of recombinant EGF-F9. Treatment with EGF-F9 increased the level of phosphorylated p38 mitogen-activated protein kinase (MAPK), but not that of phosphorylated MAPK 44/42 or c-Jun N-terminal kinase (JNK). Inhibitors of caspase-3 suppressed the release of LDH. Caspase-3 inhibitors also suppressed the attenuation of cell adhesion and phosphorylation of p38 MAPK by EGF-F9. Our data indicated that EGF-F9 activated signals for apoptosis and induced de-adhesion in a caspase-3 dependent manner.

  15. Expression of active human blood clotting factor IX in transgenic mice: use of a cDNA with complete mRNA sequence.

    PubMed Central

    Choo, K H; Raphael, K; McAdam, W; Peterson, M G

    1987-01-01

    Haemophilia B is a bleeding disorder caused by a functional deficiency of the clotting factor IX. A full length human factor IX complementary DNA clone containing all the natural mRNA sequences plus some flanking intron sequences was constructed with a metallothionein promoter and introduced into transgenic mice by microinjection into the pronuclei of fertilised eggs. The transgenic mice expressed high levels of messenger RNA, gamma-carboxylated and glycosylated protein, and biological clotting activity that are indistinguishable from normal human plasma factor IX. This study demonstrates the feasibility of expressing highly complex heterologous proteins in transgenic mice. It also provides the groundwork for the production of large amounts of human factor IX in larger transgenic livestock for therapeutic use, and the investigation of alternative genetic therapies for haemophilia B. Images PMID:3029708

  16. Replacement therapy with recombinant factor IX. A multicentre evaluation of current dosing practices in Italy

    PubMed Central

    Rocca, Alessandra; Pizzinelli, Simona; Oliovecchio, Emily; Santagostino, Elena; Rocino, Angiola; Iorio, Alfonso

    2011-01-01

    Background The in vivo recovery of recombinant factor IX (rFIX) is reported to be lower than that of plasma-derived products, with potential clinical implications for dosing. In clinical practice, a conversion (augmentation) factor is suggested to calculate the necessary doses of rFIX. The aim of this study was to assess the range of values for the conversion factor in usual clinical practice in Italy. Materials and methods The study was questionnaire-based and proposed to all Italian Haemophilia centres treating patients with haemophilia B. Age, weight, dosage used in the last effective infusion, treatment regimen (prophylaxis versus on-demand), human immunodeficiency virus (HIV) and hepatitis C virus (HCV) status, and years of previous therapy with rFIX were recorded for patients with severe haemophilia B treated with rFIX. Mean, standard deviation, median and range were calculated for demographic and treatment data for the overall population and for subgroups. The conversion factor for the theoretical dosage of 40 IU/Kg was calculated. Results Among 207 patients with severe haemophilia B being followed in 24 centres, 138 (66.7%) were being treated with rFIX. The sample of 207 patients represents 83.1% of the population of Italian patients with severe haemophilia B. The age range of the studied patients was 0–72 years (mean, 24 years) and the weight range was 3–108 kg (mean, 60 kg). Nineteen patients (14.4%) were positive for HIV and 51 (42.9%) were positive for HCV. The mean dosage of rFIX was 44 IU/Kg, with no significant difference between those receiving the product as prophylaxis or on-demand. A reduction in dosage was observed with increasing age (0.23 IU/kg/year). The mean value for the conversion factor was 1.10 ± 0.36 (median 1.00, range 0.51–2.08), when estimated for the whole population. No effect of HIV and HCV status was found on the dose prescribed. No evident correlation was found with the underlying genetic mutation. Discussion We found

  17. EGF domain of coagulation factor IX is conducive to exposure of phosphatidylserine.

    PubMed

    Hidai, Chiaki; Fujiwara, Yusuke; Kokubun, Shinichiro; Kitano, Hisataka

    2017-04-01

    Lipid rafts are an initiation site for many different signals. Recently, we reported that an EGF domain in activated coagulation factor IX (EGF-F9) increases lipid raft formation and accelerates cell migration. However, the detailed mechanism is not well understood. This study aimed to evaluate the effects of EGF-F9 on the cell membrane. A431 cells (derived from human squamous cell carcinoma) were treated with recombinant EGF-F9. Cells were immunocytochemically stained with probes for lipid rafts or phosphatidylserine (PS). After 3 min of treatment with EGF-F9, cholera toxin subunit B (CTxB) binding domains emerged at the adhesive tips of filopodia. Subsequently, CTxB staining was observed on the filopodial shaft. Finally, large clusters of CTxB domains were observed at the edge of cell bodies. Markers for lipid rafts, such as caveolin-1 and a GPI anchored protein, co-localized with CTxB. Staining with annexin V and XII revealed that PS was exposed at the tips of filopodia, translocated on filopodial shafts, and co-localized with CTxB at the rafts. Immunocytochemistry showed that scramblase-1 protein was present at the filopodial tips. Our data indicates that EGF-F9 accelerates PS exposure around the filopodial adhesion complex and induces clustering of lipid rafts in the cell body. PS exposure is thought to occur on cells undergoing apoptosis. Further study of the function of the EGF-F9 motif in mediating signal transduction is necessary because it is shared by a number of proteins.

  18. Pilot production of recombinant human clotting factor IX from transgenic sow milk.

    PubMed

    Sun, Yu-ling; Chang, Yuo-sheng; Lin, Yin-shen; Yen, Chon-ho

    2012-06-01

    Valuable pharmaceutical proteins produced from the mammary glands of transgenic livestock have potential use in the biomedical industry. In this study, recombinant human clotting factor IX (rhFIX) produced from transgenic sow milk for preclinical animal studies have been established. The transgenic sow milk was skimmed and treated with sodium phosphate buffer to remove abundant casein protein. Then, the γ-carboxylated rhFIX fraction was segregated through the Q Sepharose chromatography from uncarboxylated one. For safety issue, the process included virus inactivation by solvent/detergent (S/D) treatment. Subsequently, the S/D treated sample was loaded into the Heparin Sepharose column to recover the rhFIX fraction, which was then reapplied to the Heparin Sepharose column to enhance rhFIX purity and lower the ratio of activated form rhFIX (rhFIXa) easily. This was possible due to the higher affinity of the Heparin affinity sorbent for rhFIXa than for the rhFIX zymogen. Furthermore, an IgA removal column was used to eliminate porcine IgA in purified rhFIX. Finally, nanofiltration was performed for viral clearance. Consequently, a high-quality rhFIX product was produced (approximately 700 mg per batch). Other values for final rhFIX preparation were as follows: purity, >99%; average specific activity, 415.6±57.7 IU/mL and total milk impurity, <0.5 ng/mg. This is the first report that described the whole process and stable production of bioactive rhFIX from transgenic sow milk. The overall manufacturing process presented here has the potential for industrial production of rhFIX for treatment of hemophilia B patients.

  19. A light hydrocarbon fuel processor producing high-purity hydrogen

    NASA Astrophysics Data System (ADS)

    Löffler, Daniel G.; Taylor, Kyle; Mason, Dylan

    This paper discusses the design process and presents performance data for a dual fuel (natural gas and LPG) fuel processor for PEM fuel cells delivering between 2 and 8 kW electric power in stationary applications. The fuel processor resulted from a series of design compromises made to address different design constraints. First, the product quality was selected; then, the unit operations needed to achieve that product quality were chosen from the pool of available technologies. Next, the specific equipment needed for each unit operation was selected. Finally, the unit operations were thermally integrated to achieve high thermal efficiency. Early in the design process, it was decided that the fuel processor would deliver high-purity hydrogen. Hydrogen can be separated from other gases by pressure-driven processes based on either selective adsorption or permeation. The pressure requirement made steam reforming (SR) the preferred reforming technology because it does not require compression of combustion air; therefore, steam reforming is more efficient in a high-pressure fuel processor than alternative technologies like autothermal reforming (ATR) or partial oxidation (POX), where the combustion occurs at the pressure of the process stream. A low-temperature pre-reformer reactor is needed upstream of a steam reformer to suppress coke formation; yet, low temperatures facilitate the formation of metal sulfides that deactivate the catalyst. For this reason, a desulfurization unit is needed upstream of the pre-reformer. Hydrogen separation was implemented using a palladium alloy membrane. Packed beds were chosen for the pre-reformer and reformer reactors primarily because of their low cost, relatively simple operation and low maintenance. Commercial, off-the-shelf balance of plant (BOP) components (pumps, valves, and heat exchangers) were used to integrate the unit operations. The fuel processor delivers up to 100 slm hydrogen >99.9% pure with <1 ppm CO, <3 ppm CO 2. The

  20. The Hydrometallurgical Extraction and Recovery of High-Purity Silver

    NASA Astrophysics Data System (ADS)

    Hoffmann, James E.

    2012-06-01

    -bearing inputs, will be described in detail to demonstrate how typical chemical engineering unit process and unit operations have supplanted classic smelting and fire refining techniques. The Kennecott Copper Company, which has operated a hydrometallurgical circuit successfully for the recovery of high-purity silver from the slimes wet chlorination residue, has permitted me to provide some operation information and results using the technology. Both Phelps Dodge and Kennecott should be recognized for their forward-looking attitude in undertaking the conversion of conceptual chemistry into successful, full-scale plants. The process as employed at Phelps Dodge is discussed at length in reference (J.E. Hoffmann and B. Wesstrom: Hydrometallurgy, 1994, vol. 94, pp. 69-105).

  1. Influence of formulation factors on methyl-ALA-induced protoporphyrin IX accumulation in vivo.

    PubMed

    Donnelly, Ryan F; Juzenas, Petras; McCarron, Paul A; Ma, Li-Wei; Woolfson, A David; Moan, Johan

    2006-09-01

    Photodynamic therapy (PDT) is a medical treatment by which a combination of a photosensitising drug and visible light cause the destruction of selected cells. Thick lesions, such as nodular basal cell carcinomas (BCCs), or lesions with overlying keratinous debris, are reported as being difficult to eradicate using 5-aminolevulinic acid-based photodynamic therapy (ALA-PDT). Such treatment failures have been attributed to the shallow penetration of water-soluble drugs like ALA. In addition, the current scarcity of sophisticated drug delivery research centered on PDT applications has meant that accurate comparison of similar clinical studies is difficult. This paper investigates, for the first time, novel drug delivery systems for controlled drug delivery of methyl-ALA (M-ALA). Pressure sensitive adhesive (PSA) and bioadhesive patches containing defined M-ALA loadings and a standard cream containing equivalent amounts of drug were applied to the skin of mice for defined periods of time and the fluorescence of the protoporphyrin IX (PpIX) induced measured over 24h. Of major importance, the PSA patches containing low drug loadings induced high PpIX levels, which were limited to the site of application, after only 1h applications. Such systems have the potential to improve selectivity of PpIX accumulation, increase simplicity of treatment and, due to the low drug loadings required, reduce costs of clinical PDT. PSA patches would be most suitable for application to areas of dry skin, while bioadhesive patches would be suitable for moist areas, such as the mouth or lower female reproductive tract and have been shown here to induce significant PpIX production at the site of application after 4h applications of patches containing high drug loadings.

  2. Preparation of high purity lanthanum compounds for use in fluoride optical fibers

    SciTech Connect

    Ewing, K.J.; Buckner, L.; Jaganathan, J.; Ginther, R.; Aggarwal, I.D. . Optical Sciences Div.)

    1989-02-01

    The preparation of ultra-pure lanthanum nitrate by co-precipitation is described. Preparation of high purity lanthanum carbonate from the pure nitrate is also described. Hydrofluorination of pure lanthanum carbonate produces high purity lanthanum fluoride used in the preparation of heavy metal fluoride glasses.

  3. SIMULTANEOUS PRODUCTION OF HIGH-PURITY HYDROGEN AND SEQUESTRATION-READY CO2 FROM SYNGAS

    SciTech Connect

    Linda Denton; Hana Lorethova; Tomasz Wiltowski; Court Moorefield; Parag Kulkarni; Vladimir Zamansky; Ravi Kumar

    2003-12-01

    This final report summarizes the progress made on the program ''Simultaneous Production of High-Purity Hydrogen and Sequestration-Ready CO{sub 2} from Syngas (contract number DE-FG26-99FT40682)'', during October 2000 through September of 2003. GE Energy and Environmental Research (GE-EER) and Southern Illinois University (SIU) at Carbondale conducted the research work for this program. This program addresses improved methods to efficiently produce simultaneous streams of high-purity hydrogen and separated carbon dioxide from synthesis gas (syngas). The syngas may be produced through either gasification of coal or reforming of natural gas. The process of production of H{sub 2} and separated CO{sub 2} utilizes a dual-bed reactor and regenerator system. The reactor produces hydrogen and the regenerator produces separated CO{sub 2}. The dual-bed system can be operated under either a circulating fluidized-bed configuration or a cyclic fixed-bed configuration. Both configurations were evaluated in this project. The experimental effort was divided into lab-scale work at SIU and bench-scale work at GE-EER. Tests in a lab-scale fluidized bed system demonstrated the process for the conversion of syngas to high purity H{sub 2} and separated CO{sub 2}. The lab-scale system generated up to 95% H{sub 2} (on a dry basis). Extensive thermodynamic analysis of chemical reactions between the syngas and the fluidized solids determined an optimum range of temperature and pressure operation, where the extent of the undesirable reactions is minimum. The cycling of the process between hydrogen generation and oxygen regeneration has been demonstrated. The fluidized solids did not regenerate completely and the hydrogen purity in the reuse cycle dropped to 70% from 95% (on a dry basis). Changes in morphology and particle size may be the most dominant factor affecting the efficiency of the repeated cycling between hydrogen production and oxygen regeneration. The concept of simultaneous

  4. Characterization of IXINITY® (Trenonacog Alfa), a Recombinant Factor IX with Primary Sequence Corresponding to the Threonine-148 Polymorph

    PubMed Central

    Monroe, Dougald M.; Jenny, Richard J.; Van Cott, Kevin E.; Saward, Laura L.

    2016-01-01

    The goal of these studies was to extensively characterize the first recombinant FIX therapeutic corresponding to the threonine-148 (Thr-148) polymorph, IXINITY (trenonacog alfa [coagulation factor IX (recombinant)]). Gel electrophoresis, circular dichroism, and gel filtration were used to determine purity and confirm structure. Chromatographic and mass spectrometry techniques were used to identify and quantify posttranslational modifications. Activity was assessed as the ability to activate factor X (FX) both with and without factor VIIIa (FVIIIa) and in a standard clotting assay. All results were consistent across multiple lots. Trenonacog alfa migrated as a single band on Coomassie-stained gels; activity assays were normal and showed <0.002 IU of activated factor IX (FIXa) per IU of FIX. The molecule has >97%  γ-carboxylation and underwent the appropriate structural change upon binding calcium ions. Trenonacog alfa was activated normally with factor XIa (FXIa); once activated it bound to FVIIIa and FXa. When activated to FIXa, it was inhibited efficiently by antithrombin. Glycosylation patterns were similar to plasma-derived FIX with sialic acid content consistent with the literature reports of good pharmacokinetic performance. These studies have shown that trenonacog alfa is a highly pure product with a primary sequence and posttranslational modifications consistent with the common Thr-148 polymorphism of plasma-derived FIX. PMID:26997955

  5. A method for systematic purification from bovine plasma of six vitamin K-dependent coagulation factors: prothrombin, factor X, factor IX, protein S, protein C, and protein Z.

    PubMed

    Hashimoto, N; Morita, T; Iwanaga, S

    1985-05-01

    A systematic purification scheme is presented for the isolation of six vitamin K-dependent coagulation factors from bovine plasma in a functionally and biochemically pure state. The vitamin K-dependent proteins concentrated by the ordinary barium citrate adsorption were first separated into four fractions, fractions A, B, C, and D, by DEAE-Sephadex A-50 chromatography. From the pooled fraction A, protein S, factor IX, and prothrombin were purified by column chromatography on Blue-Sepharose CL-6B. Heparin-Sepharose chromatography of the pooled fraction B provided mainly pure factor IX, in addition to homogeneous prothrombin. A high degree of resolution of protein C and prothrombin from the pooled fraction C was obtained with a Blue-Sepharose column. This dye-ligand chromatographic procedure was also very effective for the separation of protein Z and factor X contained in the pooled fraction D. Thus, these preparative procedures allowed high recovery of milligram and gram quantities of six vitamin K-dependent proteins from 15 liters of plasma in only two chromatographic steps, except for protein S, which required three (the third step was rechromatography on Blue-Sepharose CL-6B).

  6. Magneto-Optical Study High-Purity Niobium for Superconducting RF Application

    NASA Astrophysics Data System (ADS)

    Polyanskii, A. A.; Lee, P. J.; Gurevich, A.; Sung, Zu-Hawn; Larbalestier, D. C.

    2011-03-01

    In this review we present a summary of our recent Magneto-Optical (MO) imaging of high-purity Nb for SRF cavity application. Superconducting RF cavities have been chosen as the accelerating technology for the International Linear Collider, and it is of vital importance to understand the limiting factors to the performance of these devices. We have been using a combination of MO, imaging, magnetization measurements and a variety of non-contact surface topology measurement techniques to characterize samples of high purity Nb supplied by Fermi National Accelerator Laboratory (FNAL) and Thomas Jefferson National Accelerator Facility (TJNAF). Localized non-uniformities in the superconducting properties were revealed on samples which were cut from rolled polycrystalline sheets (FNAL) and subjected to buffered chemical polishing (BCP) and heat treatments (HT) steps designed to simulate typical SRF cavity production. MO examination of the polycrystalline Nb sheets in perpendicular and in-plane fields reveals the perturbations in the critical currents caused by topological defects such as the steps between adjacent grains produced by BCP. MO examination of bi-crystals prepared from a disc cut directly from a very large grain size ingot (manufactured for TJNAF by CBMM) showed preferential flux penetration at grain boundaries for bi-crystal samples in which the GB interface was almost parallel to the externally applied field. This result was the first direct evidence of depressed superconductivity at GBs. By developing an understanding of how and why such behavior occurs, we hope to be able to improve the properties of cavity accelerators.

  7. Characterization of three abnormal factor IX variants (Bm Lake Elsinore, Long Beach, and Los Angeles) of hemophilia-B. Evidence for defects affecting the latent catalytic site.

    PubMed Central

    Usharani, P; Warn-Cramer, B J; Kasper, C K; Bajaj, S P

    1985-01-01

    Abnormal factor IX variant proteins were isolated from the plasmas of three unrelated severe hemophilia-B families that had been previously shown to contain functionally impaired molecules immunologically similar to normal factor IX. The families studied were: (1) a patient with markedly prolonged ox brain prothrombin time, designated factor IX Bm Lake Elsinore (IXBmLE); (b) three patients (brothers) with moderately prolonged ox brain prothrombin time, designated factor IX Long Beach (IXLB); and (c) a patient with normal ox brain prothrombin time designated factor IX Los Angeles (IXLA). Each variant molecule comigrates with normal factor IX (IXN) both in the sodium dodecyl sulfate and in the nondenaturing alkaline gel electrophoresis. All three variant proteins are indistinguishable from IXN in their amino acid compositions, isoelectric points, carbohydrate distributions and number of gamma-carboxyglutamic acid residues. Each variant protein undergoes a similar pattern of cleavage by factor XIa/Ca2+ and by factor VIIa/Ca2+/tissue factor, and is activated at a rate similar to that observed for IXN. All of the three variant proteins also react with an anti-IXN monoclonal antibody that interferes with the binding of activated IXN(IXaN) to thrombin-treated factor VIIIC. However, in contrast to IXaN, the cleaved IXBmLE has negligible activity (approximately 0.2%), and cleaved forms of IXLA and IXLB have significantly reduced activity (approximately 5-6%) in binding to antithrombin-III/heparin, and in activating factor VII (plus Ca2+ and phospholipid) or factor X (plus Ca2+ and phospholipid) +/- factor VIII. These data, taken together, strongly indicate that the defect in these three variant proteins resides near or within the latent catalytic site. This results in virtually a complete loss of catalytic activity of the cleaved IXBmLE molecule and approximately 95% loss of catalytic activity of the cleaved IXLA and IXLB molecules. Images PMID:3965513

  8. Characterization of three abnormal factor IX variants (Bm Lake Elsinore, Long Beach, and Los Angeles) of hemophilia-B. Evidence for defects affecting the latent catalytic site.

    PubMed

    Usharani, P; Warn-Cramer, B J; Kasper, C K; Bajaj, S P

    1985-01-01

    Abnormal factor IX variant proteins were isolated from the plasmas of three unrelated severe hemophilia-B families that had been previously shown to contain functionally impaired molecules immunologically similar to normal factor IX. The families studied were: (1) a patient with markedly prolonged ox brain prothrombin time, designated factor IX Bm Lake Elsinore (IXBmLE); (b) three patients (brothers) with moderately prolonged ox brain prothrombin time, designated factor IX Long Beach (IXLB); and (c) a patient with normal ox brain prothrombin time designated factor IX Los Angeles (IXLA). Each variant molecule comigrates with normal factor IX (IXN) both in the sodium dodecyl sulfate and in the nondenaturing alkaline gel electrophoresis. All three variant proteins are indistinguishable from IXN in their amino acid compositions, isoelectric points, carbohydrate distributions and number of gamma-carboxyglutamic acid residues. Each variant protein undergoes a similar pattern of cleavage by factor XIa/Ca2+ and by factor VIIa/Ca2+/tissue factor, and is activated at a rate similar to that observed for IXN. All of the three variant proteins also react with an anti-IXN monoclonal antibody that interferes with the binding of activated IXN(IXaN) to thrombin-treated factor VIIIC. However, in contrast to IXaN, the cleaved IXBmLE has negligible activity (approximately 0.2%), and cleaved forms of IXLA and IXLB have significantly reduced activity (approximately 5-6%) in binding to antithrombin-III/heparin, and in activating factor VII (plus Ca2+ and phospholipid) or factor X (plus Ca2+ and phospholipid) +/- factor VIII. These data, taken together, strongly indicate that the defect in these three variant proteins resides near or within the latent catalytic site. This results in virtually a complete loss of catalytic activity of the cleaved IXBmLE molecule and approximately 95% loss of catalytic activity of the cleaved IXLA and IXLB molecules.

  9. Expression of human factor IX in rabbit hepatocytes by retrovirus-mediated gene transfer: Potential for gene therapy of hemophilia B

    SciTech Connect

    Thompson, A.R. Puget Sound Blood Center, Seattle, WA ); Darlington, G. ); Armentano, D.; Woo, S.L.C.

    1990-08-01

    Hemophilia B (Christmas disease) is a chromosome X-linked blood clotting disorder which results when factor IX is deficient or functionally defective. The enzyme is synthesized in the liver, and the existence of animal models for this genetic disease will permit the development of somatic gene therapy protocols aimed at transfer of the functional gene into the liver. The authors report the construction of an N2-based recombinant retroviral vector, NCMVFIX, for efficient transfer and expression of human factor IX cDNA in primary rabbit hepatocytes. In this construct the human cytomegalovirus immediate early promoter directs the expression of factor IX. Hepatocytes were isolated from 3-week-old New Zealand White rabbits, infected with the recombinant virus, and analyzed for secretion of active factor IX. The infected rabbit hepatocytes produced human factor IX that is indistinguishable from enzyme derived from normal human plasma. The recombinant protein is sufficiently {gamma}-carboxylated and is functionally active in clotting assays. These results establish the feasibility of using infected hepatocytes for the expression of this protein and are a step toward the goal of correcting hemophilia B by hepatic gene transfer.

  10. Persistent expression of human clotting factor IX from mouse liver after intravenous injection of adeno-associated virus vectors

    PubMed Central

    Koeberl, Dwight D.; Alexander, Ian E.; Halbert, Christine L.; Russell, David W.; Miller, A. Dusty

    1997-01-01

    We previously found that gene transduction by adeno-associated virus (AAV) vectors in cell culture can be stimulated over 100-fold by treatment of the target cells with agents that affect DNA metabolism, such as irradiation or topoisomerase inhibitors. Here we show that previous γ-irradiation increased the transduction rate in mouse liver by up to 900-fold, and the topoisomerase inhibitor etoposide increased transduction by about 20-fold. Similar rates of hepatic transduction were obtained by direct injection of the liver or by systemic delivery via tail vein injection. Hepatocytes were much more efficiently transduced than other cells after systemic delivery, and up to 3% of all hepatocytes could be transduced after one vector injection. The presence of wild-type AAV, which contaminates many AAV vector preparations, was required to observe a full response to γ-irradiation. Injection of mice with AAV vectors encoding human clotting factor IX after γ-irradiation resulted in synthesis of low levels of human clotting factor IX for the 5-month period of observation. These studies show the potential of targeted gene transduction of the liver by AAV vectors for treatment of various hematological or metabolic diseases. PMID:9037069

  11. Breeding of transgenic cattle for human coagulation factor IX by a combination of lentiviral system and cloning.

    PubMed

    Monzani, P S; Sangalli, J R; De Bem, T H C; Bressan, F F; Fantinato-Neto, P; Pimentel, J R V; Birgel-Junior, E H; Fontes, A M; Covas, D T; Meirelles, F V

    2013-02-28

    Recombinant coagulation factor IX must be produced in mammalian cells because FIX synthesis involves translational modifications. Human cell culture-based expression of human coagulation factor IX (hFIX) is expensive, and large-scale production capacity is limited. Transgenic animals may greatly increase the yield of therapeutic proteins and reduce costs. In this study, we used a lentiviral system to obtain transgenic cells and somatic cell nuclear transfer (SCNT) to produce transgenic animals. Lentiviral vectors carrying hFIX driven by 3 bovine β-casein promoters were constructed. Bovine epithelial mammary cells were transduced by lentivirus, selected with blasticidin, plated on extracellular matrix, and induced by lactogenic hormones; promoter activity was evaluated by quantitative PCR. Transcriptional activity of the 5.335-kb promoter was 6-fold higher than the 3.392- and 4.279-kb promoters, which did not significantly differ. Transgenic bovine fibroblasts were transduced with lentivirus carrying the 5.335-kb promoter and used as donor cells for SCNT. Cloned transgenic embryo production yielded development rates of 28.4%, similar to previous reports on cloned non-transgenic embryos. The embryos were transferred to recipient cows (N = 21) and 2 births of cloned transgenic cattle were obtained. These results suggest combination of the lentiviral system and cloning may be a good strategy for production of transgenic cattle.

  12. Targeting of the epidermal growth factor receptor with mesoporphyrin IX-peptide conjugates.

    PubMed

    Fontenot, Krystal R; Ongarora, Benson G; LeBlanc, Logan E; Zhou, Zehua; Jois, Seetharama D; Vicente, M Graça H

    2016-01-01

    The synthesis and in vitro evaluation of four mesoporphyrin IX-peptide conjugates designed to target EGFR, over-expressed in colorectal and other cancers, are reported. Two peptides with known affinity for EGFR, LARLLT (1) and GYHWYGYTPQNVI (2), were conjugated to mesoporphyrin IX (MPIX, 3) via one or both the propionic side chains, directly (4, 5) or with a triethylene glycol spacer (7, 8). The conjugates were characterized using NMR, MS, CD, SPR, UV-vis and fluorescence spectroscopies. Energy minimization and molecular dynamics suggest different conformations for the conjugates. SPR studies show that conjugate 4, bearing two LARLLT with no PEG spacers, has the greatest affinity for binding to EGFR, followed by conjugate 7 with two PEG and two LARLLT sequences. Molecular modeling and docking studies suggest that both conjugates 4 and 7 can bind to monomer and dimer EGFR in open and closed conformations. The cytotoxicity and cellular targeting ability of the conjugates were investigated in human HEp2 cells over-expressing EGFR. All conjugates showed low dark- and photo-toxicities. The cellular uptake was highest for conjugates 4 and 8 and lowest for 7 bearing two LARLLT linked via PEG groups, likely due to decreased hydrophobicity. Among the conjugates investigated 4 is the most efficient EGFR-targeting agent, and therefore the most promising for the detection of cancers that over-express EGFR.

  13. Targeting of the epidermal growth factor receptor with mesoporphyrin IX-peptide conjugates

    PubMed Central

    Fontenot, Krystal R.; Ongarora, Benson G.; LeBlanc, Logan E.; Zhou, Zehua; Jois, Seetharama D.; Vicente, M. Graça H.

    2016-01-01

    The synthesis and in vitro evaluation of four mesoporphyrin IX-peptide conjugates designed to target EGFR, over-expressed in colorectal and other cancers, are reported. Two peptides with known affinity for EGFR, LARLLT (1) and GYHWYGYTPQNVI (2), were conjugated to mesoporphyrin IX (MPIX, 3) via one or both the propionic side chains, directly (4, 5) or with a triethylene glycol spacer (7, 8). The conjugates were characterized using NMR, MS, CD, SPR, UV-vis and fluorescence spectroscopies. Energy minimization and molecular dynamics suggest different conformations for the conjugates. SPR studies show that conjugate 4, bearing two LARLLT with no PEG spacers, has the greatest affinity for binding to EGFR, followed by conjugate 7 with two PEG and two LARLLT sequences. Molecular modeling and docking studies suggest that both conjugates 4 and 7 can bind to monomer and dimer EGFR in open and closed conformations. The cytotoxicity and cellular targeting ability of the conjugates were investigated in human HEp2 cells over-expressing EGFR. All conjugates showed low dark- and photo-toxicities. The cellular uptake was highest for conjugates 4 and 8 and lowest for 7 bearing two LARLLT linked via PEG groups, likely due to decreased hydrophobicity. Among the conjugates investigated 4 is the most efficient EGFR-targeting agent, and therefore the most promising for the detection of cancers that over-express EGFR. PMID:27738394

  14. Visualizing the von Willebrand factor/glycoprotein Ib-IX axis with a platelet-type von Willebrand disease mutation.

    PubMed

    Guerrero, Jose A; Kyei, Mark; Russell, Susan; Liu, Junling; Gartner, T Kent; Storrie, Brian; Ware, Jerry

    2009-12-24

    Platelet-type von Willebrand disease (PT-VWD) is a bleeding disorder of the platelet glycoprotein Ib-IX/von Willebrand factor (VWF) axis caused by mutations in the glycoprotein Ib-IX receptor that lead to an increased affinity with VWF. In this report, platelets from a mouse expressing a mutation associated with PT-VWD have been visualized using state-of-the art image collection and processing. Confocal analysis revealed that VWF bound to the surface of single platelets and bridging micro-aggregates of platelets. Surface-bound VWF appears as a large, linear structure on the surface of 50% of the PT-VWD platelets. In vivo thrombus formation after chemical injury to the carotid artery revealed a severe impairment to occlusion as a consequence of the PT-VWD mutation. In vitro stimulation of PT-VWD platelets with adenosine diphosphate or thrombin demonstrates a significant block in their ability to bind fibrinogen. The impairment of in vivo thrombus formation and in vitro fibrinogen binding are more significant than might be expected from the observed platelet binding to VWF polymers over a small portion of the plasma membrane. Visualization of the receptor/ligand interaction and characterization of a severe antithrombotic phenotype provide a new understanding on the molecular basis of bleeding associated with the PT-VWD phenotype.

  15. Synthesis of High Purity Silicon from Rice Husks

    NASA Astrophysics Data System (ADS)

    Larbi, Kingsley Kweku

    Impurity optimized silicon is needed for the advancement of terrestrial photovoltaic power generation. In this study the possibility of producing solar grade silicon from rice husks has been pursued. An integrated process flowsheet was developed and practiced that included initial leaching, reduction of Rice husk ash (RHA) and post-reduction purification of silicon. Metallothermic reduction of purified RHA with magnesium was investigated within the temperature range of 500-950 °C. The reduction product was purified by two stage acid leaching sequence. Analysis of the final silicon powder product by XRD and ICP-OES showed crystalline silicon with boron content to be less than 3ppm- corresponding to reduction by a factor greater than 10, whilst the phosphorus content was reduced by a factor of over 20 and reaching less than 73ppm. The effects of temperature, magnesium amount and leaching agents optimized in this study. A one step test melting was also carried out to convert the silicon powder into silicon chunks.

  16. Blood Oxygenation Level-dependent Magnetic Resonance Imaging of Breast Cancer: Correlation with Carbonic Anhydrase IX and Vascular Endothelial Growth Factor

    PubMed Central

    Wang, Ying; Liu, Min; Jin, Mu-Lan

    2017-01-01

    Background: Blood oxygenation level-dependent magnetic resonance imaging (BOLD-MRI) is a functional MRI technique which involves using the paramagnetic properties of deoxyhemoglobin to image the local tissue oxygen concentration. The purpose of this study was to investigate whether BOLD-MRI could evaluate hypoxia and angiogenesis of breast invasive ductal carcinoma (IDC). Methods: Ninety-eight female patients with IDC were retrospectively included in this research. All patients underwent breast BOLD-MRI at 3.0 T before surgery. R2* values of BOLD-MRI were measured. The expression of carbonic anhydrase IX (CA IX) and vascular endothelial growth factor (VEGF) was analyzed by immunohistochemistry. Spearman's correlation analysis was used to correlate R2* value with CA IX and VEGF levels. Results: Heterogeneous intensity on BOLD-MRI images was the main finding of IDCs. The mean R2* value was 52.8 ± 18.6 Hz. The R2* values in patients with axillary lymph node metastasis were significantly higher than the R2* values in patients without axillary lymph node metastasis (t = 2.882, P = 0.005). R2* values increased with CA IX level and positively correlated with the level of CA IX (r = 0.616, P < 0.001); however, R2* value had no significantly correlation with the level of VEGF (r = 0.110, P = 0.281). Conclusion: BOLD-MRI could noninvasively evaluate chronic hypoxia of IDC, but not angiogenesis. PMID:28051026

  17. The pattern of factor IX germ-line mutation in Asians is similar to that of Caucasians.

    PubMed Central

    Bottema, C D; Ketterling, R P; Yoon, H S; Sommer, S S

    1990-01-01

    To begin documenting the pattern of germ-line mutations in different human races, we have delineated the mutation in nine Korean families with hemophilia B by direct genomic sequencing of the regions of likely functional significance in the factor IX gene. An evaluation of these mutations in combination with previously described point mutations in the factor IX gene of Asians indicates that transitions predominate followed by transversions and microdeletions/insertions. Transitions at the dinucleotide CpG are a dramatic hot spot of mutation. This pattern of mutation is very similar to that observed in Caucasians with hemophilia B, despite the many differences between Asians (mostly Koreans) and Caucasians in diet, environment and cultural life-styles. The similarity may reflect the predominance of endogenous processes or ubiquitous mutagens rather than specific mutagens in the environment. The following additional conclusions emerge: (1) The missense mutations in Asians occur at evolutionarily conserved amino acids. When combined with the previous data this makes it likely that more than two-thirds of the missense mutations which could possibly occur at nonconserved amino acids do not cause hemophilia B. (2) Surprisingly, a change in the sixth base of the intron 2 donor splice-junction sequence is associated with severe disease in HB 74/77. (3) Direct carrier testing of nine Korean families demonstrates that the stability of DNA at ambient temperature in blood with the anticoagulant ACD solution B makes it feasible for a diagnostic laboratory to perform such testing at a distance of 7,000 miles. Carrier testing revealed that the mutation in HB78 arose in his mother's germ-line.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2220823

  18. Development, fabrication and test of a high purity silica heat shield

    NASA Technical Reports Server (NTRS)

    Rusert, E. L.; Drennan, D. N.; Biggs, M. S.

    1978-01-01

    A highly reflective hyperpure ( 25 ppm ion impurities) slip cast fused silica heat shield material developed for planetary entry probes was successfully scaled up. Process development activities for slip casting large parts included green strength improvements, casting slip preparation, aggregate casting, strength, reflectance, and subscale fabrication. Successful fabrication of a one-half scale Saturn probe (shape and size) heat shield was accomplished while maintaining the silica high purity and reflectance through the scale-up process. However, stress analysis of this original aggregate slip cast material indicated a small margin of safety (MS. = +4%) using a factor of safety of 1.25. An alternate hyperpure material formulation to increase the strength and toughness for a greater safety margin was evaluated. The alternate material incorporates short hyperpure silica fibers into the casting slip. The best formulation evaluated has a 50% by weight fiber addition resulting in an 80% increase in flexural strength and a 170% increase in toughness over the original aggregate slip cast materials with comparable reflectance.

  19. Electron spin resonance spectroscopy of high purity crystals at millikelvin temperatures

    NASA Astrophysics Data System (ADS)

    Farr, Warrick G.; Creedon, Daniel L.; Goryachev, Maxim; Benmessai, Karim; Tobar, Michael E.

    2013-12-01

    Progress in the emerging field of engineered quantum systems requires the development of devices that can act as quantum memories. The realisation of such devices by doping solid state cavities with paramagnetic ions imposes a trade-off between ion concentration and cavity coherence time. Here, we investigate an alternative approach involving interactions between photons and naturally occurring impurity ions in ultra-pure crystalline microwave cavities exhibiting exceptionally high quality factors. We implement a hybrid Whispering Gallery/Electron Spin Resonance method to perform rigorous spectroscopy of an undoped single-crystal sapphire resonator over the frequency range 8{19 GHz, and at external applied DC magnetic fields up to 0.9 T. Measurements of a high purity sapphire cooled close to 100 mK reveal the presence of Fe3+, Cr3+, and V2+ impurities. A host of electron transitions are measured and identified, including the two-photon classically forbidden quadrupole transition (Δms = 2) for Fe3+, as well as hyperfine transitions of V2+.

  20. Mechanical Properties of High Purity Niobium - Novel Measurements

    SciTech Connect

    Ganapati Myneni

    2003-09-01

    One of the procedures to improve the performance of superconducting niobium cavities is a heat treatment for several hours in an ultrahigh vacuum at temperatures between 800C and 1400C for hydrogen degassing or post-purification, respectively. However, it was recently observed with Spallation Neutron Source Project (SNS) prototype cavities, that a heat treatment at 800 C for even 1 hour degraded the mechanical properties of RRR niobium, in particular the yield strength. This lower strength resulted in cavity deformations during handling thus affecting both their resonant frequency and field profile. In addition to lowering the yield strength, it was observed in some lots of material that the Young's modulus was also apparently reduced by a factor of 2 as a result of the hydrogen outgassing at 800 C. Surprisingly, material received at other national laboratories exhibited similar anomalous behavior even without any heat treatments in vacuum. Based on these observations a multi-institutional collaborative basic research activity on high RRR niobium (determination of Nb yield strength as a function of grain size, work hardening, chemical composition, and heat treatment temperature) has been initiated by JLAB to gain a better understanding of the material properties affecting the mechanical behavior In this contribution, a brief review of the measurements at JLAB, at the Materials Science and Engineering Department of the University of Virginia, at the Analytical Chemistry and Metallurgy Divisions of the National Institute of Standard and Technology, Gaithersburg and in the Department of Physics, SUNY, Albany are presented. The measurements include yield strength, hardness, ultrasonic velocity, crystallographic structure, microstructure, determination of interstitial contents using internal friction; particular emphasis is placed on determining the hydrogen concentration in the niobium via Cold Neutron Prompt Gamma-Ray Activation Analysis and Neutron Incoherent

  1. The Next Generation Safeguards Initiative s High-Purity Uranium-233 Preservation Effort

    SciTech Connect

    Krichinsky, Alan M; Bostick, Debra A; Giaquinto, Joseph; Bayne, Charles; Goldberg, Dr. Steven A.; Humphrey, Dr. Marc; Hutcheon, Dr. Ian D.; Sobolev, Taissa

    2012-01-01

    High-purity 233U serves as a crucial reference material for accurately quantifying and characterizing uranium. The most accurate analytical results which can be obtained only with high-purity 233U certified reference material (CRM) are required when used to confirm compliance with international safeguards obligations and international nonproliferation agreements. The U.S. supply of 233U CRM is almost depleted, and existing domestic stocks of this synthetic isotope are scheduled to be down-blended for disposition with depleted uranium beginning in 2015. Down blending batches of high-purity 233U will permanently eliminate the value of this material as a CRM. Furthermore, no replacement 233U stocks are expected to be produced in the future due to a lack of operating production capability and the high cost of replacing such capability. Therefore, preserving select batches of high-purity 233U is of great value and will assist in retaining current analytical capabilities for uranium-bearing samples. Any organization placing a priority on accurate results of uranium analyses, or on the confirmation of trace uranium in environmental samples, has a vested interest in preserving this material. This paper describes the need for high-purity 233U, the consequences organizations and agencies face if this material is not preserved, and the progress and future plans for preserving select batches of the purest 233U materials from disposition. This work is supported by the Next Generation Safeguards Initiative, Office of Nonproliferation and International Security, National Nuclear Security Administration.

  2. Population genetics of coagulant factor IX: frequencies of two DNA polymorphisms in five ethnic groups.

    PubMed Central

    Lubahn, D B; Lord, S T; Bosco, J; Kirshtein, J; Jeffries, O J; Parker, N; Levtzow, C; Silverman, L M; Graham, J B

    1987-01-01

    Two frequently used restriction-enzyme polymorphisms (RFLPs) of coagulant F.IX, TaqI and XmnI, have been examined in five ethnic groups: white Americans, black Americans, East Indians, Chinese, and Malays. There is a distinct "cline" in the frequencies of both polymorphisms, from white Americans to Malays. The rarer type 2 alleles of both polymorphisms, in which middle recognition sites are present--and which in our sample reach their highest frequencies in white Americans--are marginally higher in four groups of Europeans previously reported by others. The frequencies of the rarer alleles are significantly higher in Europeans than in black Americans and East Indians, and these alleles are essentially absent in Chinese and Malays. The frequency of heterozygosity diminishes in the same order, being zero in Malays for both polymorphisms. The polymorphisms are in strong linkage disequilibrium, and in all groups the type 1 allele for TaqI is disproportionately accompanied by the type 1 allele for XmnI. The paucity of type 2 alleles and the low rate of heterozygosity in four non-European groups suggest that the polymorphisms will be of little diagnostic value south of Gibraltar and east of Suez. This prediction is confirmed by the observed haplotype frequencies in the black American and the Oriental groups. PMID:2884869

  3. Impurity distribution in high purity germanium crystal and its impact on the detector performance

    NASA Astrophysics Data System (ADS)

    Wang, Guojian; Amman, Mark; Mei, Hao; Mei, Dongming; Irmscher, Klaus; Guan, Yutong; Yang, Gang

    High-purity germanium crystals were grown in a hydrogen atmosphere using the Czochralski method. The axial and radial distributions of impurities in the crystals were measured by Hall effect and Photo-thermal ionization spectroscopy (PTIS). Amorphous semiconductor contacts were deposited on the germanium crystals to make detectors. Three planar detectors were fabricated from three crystals with different net carrier concentrations (1.7, 7.9 and 10x1010 cm-3). We evaluated the electrical and spectral performance of three detectors. Measurements of gamma-ray spectra from 137Cs, 241Am and 60Co sources demonstrate that the detectors have excellent energy resolution. The relationship between the impurities and detector's energy resolution was analyzed. Keywords: High-purity germanium crystal, High-purity germanium detector This work is supported by DOE grant DE-FG02-10ER46709 and the state of South Dakota..

  4. Determination of uranium, thorium, and 18 other elements in high-purity molybdenum by radiochemical neutron activation analysis

    SciTech Connect

    Theimer, K.H.; Krivan, V. )

    1990-12-15

    A radiochemical neutron activation analysis technique for the determination of uranium and thorium in high-purity molybdenum via the indicator radionuclides {sup 239}Np for U and {sup 233}Pa for Th has been developed. Simultaneously, the elements Ag, Co, Cr, Cs, Cu, Fe, Ga, In, Ir, K, Mn, Na, Ni, Rb, Ru, Sc, Se, and Zn can be determined, too. The elements Hf, Sb, Ta, Sn, and W were determined by instrumental neutron activation analysis. The radiochemical separation is performed by anion exchange on a Dowex 1 {times} 8 column from a 20 M HF/3% H{sub 2}O{sub 2} medium. A limit of detection of 4 ng/g for uranium and 40 pg/g for thorium can be achieved. For the other elements, the limits of detection are between 1 pg/g and 100 ng/g. A modified more selective separation of the indicator radionuclide of Th, {sup 233}Pa, allows improvement of the limit of detection for Th by a factor up to 5. This technique was applied to the analysis of high-purity molybdenum, and the results of a number of elements were compared with those of other techniques.

  5. Production of High-purity Radium-223 from Legacy Actinium-Beryllium Neutron Sources

    SciTech Connect

    Z. Soderquist, Chuck; K. McNamara, Bruce; R. Fisher, Darrell

    2012-06-01

    Radium-223 is a short-lived alpha-particle-emitting radionuclides with potential applications in cancer treatment. Research to develop new radiopharmaceuticals employing 223Ra has been hindered by poor availability due to the small quantities of parent actinium-227 available world-wide. The purpose of this study was to develop innovative and cost-effective methods to obtain high-purity 223Ra from 227Ac. We obtained 227Ac from two surplus actinium-beryllium neutron generators. We retrieved the actinium/beryllium buttons from the sources and dissolved them in a sulfuric-nitric acid solution. A crude actinium solid was recovered from the solution by coprecipitation with thorium fluoride, leaving beryllium in solution. The crude actinium was purified to provide about 40 milligrams of actinium nitrate using anion exchange in methanol-water-nitric acid solution. The purified actinium was then used to generate high-purity 223Ra. We extracted 223Ra using anion exchange in a methanol-water-nitric acid solution. After the radium was separated, actinium and thorium were then eluted from the column and dried for interim storage. This single-pass separation produces high purity, carrier-free 223Ra product, and does not disturb the 227Ac/227Th equilibrium. A high purity, carrier-free 227Th was also obtained from the actinium using a similar anion exchange in nitric acid. These methods enable efficient production of 223Ra for research and new alpha-emitter radiopharmaceutical development.

  6. Low temperature recombination and trapping analysis in high purity gallium arsenide by microwave photodielectric techniques

    NASA Technical Reports Server (NTRS)

    Khambaty, M. B.; Hartwig, W. H.

    1972-01-01

    Some physical theories pertinent to the measurement properties of gallium arsenide are presented and experimental data are analyzed. A model for explaining recombination and trapping high purity gallium arsenide, valid below 77 K is assembled from points made at various places and an appraisal is given of photodielectric techniques for material property studies.

  7. Production of high-purity radium-223 from legacy actinium-beryllium neutron sources.

    PubMed

    Soderquist, Chuck Z; McNamara, Bruce K; Fisher, Darrell R

    2012-07-01

    Radium-223 is a short-lived alpha-particle-emitting radionuclide with potential applications in cancer treatment. Research to develop new radiopharmaceuticals employing (223)Ra has been hindered by poor availability due to the small quantities of parent actinium-227 available world-wide. The purpose of this study was to develop innovative and cost-effective methods to obtain high-purity (223)Ra from (227)Ac. We obtained (227)Ac from two surplus actinium-beryllium neutron generators. We retrieved the actinium/beryllium buttons from the sources and dissolved them in a sulfuric-nitric acid solution. A crude actinium solid was recovered from the solution by coprecipitation with thorium fluoride, leaving beryllium in solution. The crude actinium was purified to provide about 40 milligrams of actinium nitrate using anion exchange in methanol-water-nitric acid solution. The purified actinium was then used to generate high-purity (223)Ra. We extracted (223)Ra using anion exchange in a methanol-water-nitric acid solution. After the radium was separated, actinium and thorium were then eluted from the column and dried for interim storage. This single-pass separation produces high purity, carrier-free (223)Ra product, and does not disturb the (227)Ac/(227)Th equilibrium. A high purity, carrier-free (227)Th was also obtained from the actinium using a similar anion exchange in nitric acid. These methods enable efficient production of (223)Ra for research and new alpha-emitter radiopharmaceutical development.

  8. Variations among Japanese of the factor IX gene (F9) detected by PCR-denaturing gradient gel electrophoresis

    SciTech Connect

    Satoh, Chiyoko; Takahashi, Norio; Asakawa, Junichi; Hiyama, Keiko; Kodaira, Meiko )

    1993-01-01

    In the course of feasibility studies to examine the efficiencies and practicalities of various techniques for screening for genetic variations, the human coagulation factor IX (F9) genes of 63 Japanese families were examined by PCR-denaturing gradient gel electrophoresis (PCR-DGGE). Four target sequences with lengths of 983-2,891 bp from the F9 genes of 126 unrelated individuals from Hiroshima and their 100 children were amplified by PCR, digested with restriction enzymes to approximately 500-bp fragments, and examined by DGGE - a total of 6,724 bp being examined per individual. GC-rich sequences (GC-clamps) of 40 bp were attached to both ends of the target sequences, as far as was feasible. Eleven types of new nucleotide substitutions were detected in the population, none of which produced RFLPs or caused hemophilia B. By examining two target sequences in a single lane, approximately 8,000 bp in a diploid individual could be examined. This approach is very effective for the detection of variations in DNA and is applicable to large-scale population studies. 46 refs., 3 figs., 1 tab.

  9. Low cost industrial production of coagulation factor IX bioencapsulated in lettuce cells for oral tolerance induction in hemophilia B.

    PubMed

    Su, Jin; Zhu, Liqing; Sherman, Alexandra; Wang, Xiaomei; Lin, Shina; Kamesh, Aditya; Norikane, Joey H; Streatfield, Stephen J; Herzog, Roland W; Daniell, Henry

    2015-11-01

    Antibodies (inhibitors) developed by hemophilia B patients against coagulation factor IX (FIX) are challenging to eliminate because of anaphylaxis or nephrotic syndrome after continued infusion. To address this urgent unmet medical need, FIX fused with a transmucosal carrier (CTB) was produced in a commercial lettuce (Simpson Elite) cultivar using species specific chloroplast vectors regulated by endogenous psbA sequences. CTB-FIX (∼1 mg/g) in lyophilized cells was stable with proper folding, disulfide bonds and pentamer assembly when stored ∼2 years at ambient temperature. Feeding lettuce cells to hemophilia B mice delivered CTB-FIX efficiently to the gut immune system, induced LAP(+) regulatory T cells and suppressed inhibitor/IgE formation and anaphylaxis against FIX. Lyophilized cells enabled 10-fold dose escalation studies and successful induction of oral tolerance was observed in all tested doses. Induction of tolerance in such a broad dose range should enable oral delivery to patients of different age groups and diverse genetic background. Using Fraunhofer cGMP hydroponic system, ∼870 kg fresh or 43.5 kg dry weight can be harvested per 1000 ft(2) per annum yielding 24,000-36,000 doses for 20-kg pediatric patients, enabling first commercial development of an oral drug, addressing prohibitively expensive purification, cold storage/transportation and short shelf life of current protein drugs.

  10. Low cost industrial production of coagulation factor IX bioencapsulated in lettuce cells for oral tolerance induction in hemophilia B

    PubMed Central

    Su, Jin; Zhu, Liqing; Sherman, Alexandra; Wang, Xiaomei; Lin, Shina; Kamesh, Aditya; Norikane, Joey H.; Streatfield, Stephen J.; Herzog, Roland W.; Daniell, Henry

    2015-01-01

    Antibodies (inhibitors) developed by hemophilia B patients against coagulation factor IX (FIX) are challenging to eliminate because of anaphylaxis or nephrotic syndrome after continued infusion. To address this urgent unmet medical need, FIX fused with a transmucosal carrier (CTB) was produced in a commercial lettuce (Simpson Elite) cultivar using species specific chloroplast vectors regulated by endogenous psbA sequences. CTB-FIX (~1mg/g) in lyophilized cells was stable with proper folding, disulfide bonds and pentamer assembly when stored ~2 years at ambient temperature. Feeding lettuce cells to hemophilia B mice delivered CTB-FIX efficiently to the gut immune system, induced LAP+ regulatory T cells and suppressed inhibitor/IgE formation and anaphylaxis against FIX. Lyophilized cells enabled 10-fold dose escalation studies and successful induction of oral tolerance was observed in all tested doses. Induction of tolerance in such a broad dose range should enable oral delivery to patients of different age groups and diverse genetic background. Using Fraunhofer cGMP hydroponic system, ~870 kg fresh or 43.5 kg dry weight can be harvested per 1000 ft2 per annum yielding 24,000–36,000 doses for 20-kg pediatric patients, enabling first commercial development of an oral drug, addressing prohibitively expensive purification, cold storage/transportation and short shelf life of current protein drugs. PMID:26302233

  11. Performance of A Compact Multi-crystal High-purity Germanium Detector Array for Measuring Coincident Gamma-ray Emissions

    SciTech Connect

    Howard, Chris; Daigle, Stephen; Buckner, Matt; Erikson, Luke E.; Runkle, Robert C.; Stave, Sean C.; Champagne, Art; Cooper, Andrew; Downen, Lori; Glasgow, Brian D.; Kelly, Keegan; Sallaska, Anne

    2015-02-18

    The Multi-sensor Airborne Radiation Survey (MARS) detector is a 14-crystal array of high-purity germanium (HPGe) detectors housed in a single cryostat. The array was used to measure the astrophysical S-factor for the 14N(p,γ)15O* reaction for several transition energies at an effective center of mass energy of 163 keV. Owing to the segmented nature of the MARS detector, the effect of gamma-ray summing was greatly reduced in comparison to past experiments which utilized large, single-crystal detectors. The new S-factor values agree within the uncertainties with the past measurements. Details of the analysis and detector performance will be presented.

  12. [Construction of nonsense-mutated eukaryotic expression vector of factor IX gene and its expression in COS-7 cells].

    PubMed

    Nie, Xin; Yang, Lin-Hua; Chai, Bao-Feng; Shen, Quan; Zhang, Yuan; Zhang, Yao-Fang; Chen, Jian-Fang

    2010-06-01

    The purpose of this study was to construct 4 types of nonsense-mutated eukaryotic expression plasmids of fIX gene, using pcDNA3.1 plasmid containing fIX cDNA as template, and to identify, then to perform their expression in COS-7 cells. These stop mutants constructed by site-directed mutagenesis based on PCR, and further confirmed by DNA sequencing. COS-7 cells were transfected with either the wild-type or mutated fIX expression constructs, then the relative expression levels of fIX mRNA were detected by real time fluorescent quantitative PCR. The result showed that except the designed sites, there were no other nucleotide mutation in the sequences of four nonsense mutants. The results of real time PCR proved that the nonsense-mutated vectors can be effectively expressed in COS-7 cells. It is concluded that the nonsense-mutated eukaryotic expression vectors of fIX gene have been successfully constructed and can express in COS-7 cells, which provides the material basis for further researches on mechanism and treatment of FIX deficiency and the function defects caused by nonsense mutation.

  13. Comparison of Deformation in High-Purity Single/Large Grain and Polycrystalline Niobium Superconducting Cavities

    SciTech Connect

    Ganapati Rao Myneni; Peter Kneisel

    2005-07-10

    The current approach for the fabrication of superconducting radio frequency (SRF) cavities is to roll and deep draw sheets of polycrystalline high-purity niobium. Recently, a new technique was developed at Jefferson Laboratory that enables the fabrication of single-crystal high-purity Nb SRF cavities. To better understand the differences between SRF cavities fabricated out of fine-grained polycrystalline sheet in the standard manner and single crystal cavities fabricated by the new technique, two half-cells were produced according to the two different procedures and compared using a variety of analytical techniques including optical microscopy, scanning laser confocal microscopy, profilometry, and X-ray diffraction. Crystallographic orientations, texture, and residual stresses were determined in the samples before and after forming and this poster presents the results of this ongoing study.

  14. Radiotracer study of the preparation of high-purity lanthanum fluoride

    SciTech Connect

    Ewing, K.J.; Jaganathan, J.; Peitersen, L.; Aggarwal, I.D. ); Sommers, J.A.; Fahey, J.V. )

    1992-06-01

    This paper reports that the behavior of the impurities iron, cobalt, yttrium, and cerium is determined via radiotracer techniques for the preparation of high-purity lanthanum fluoride. The behavior of nickel and copper during the coprecipitation of a lanthanum nitrate solution is determined by graphite furnace atomic absorption spectrometric (GFAAS) analysis. There is no commercially available radiotracer for neodymium, a key impurity associated with absorption losses in fluoride glasses. However, the chemical behavior of neodymium and that of yttrium are very similar and, therefore, it is reasonable to assume that the behavior of yttrium throughout the processing is indicative of the behavior of neodymium. The concentrations of impurities in lanthanum nitrate, carbonate, and fluoride are estimated using the radiotracer and GFAAS data for each processing step. Results indicate that while high-purity lanthanum carbonate can be prepared, any impurities present in the lanthanum carbonate will be carried quantitatively into lanthanum fluoride upon hydrofluorination.

  15. Characterization of a high-purity germanium detector for small-animal SPECT.

    PubMed

    Johnson, Lindsay C; Campbell, Desmond L; Hull, Ethan L; Peterson, Todd E

    2011-09-21

    We present an initial evaluation of a mechanically cooled, high-purity germanium double-sided strip detector as a potential gamma camera for small-animal SPECT. It is 90 mm in diameter and 10 mm thick with two sets of 16 orthogonal strips that have a 4.5 mm width with a 5 mm pitch. We found an energy resolution of 0.96% at 140 keV, an intrinsic efficiency of 43.3% at 122 keV and a FWHM spatial resolution of approximately 1.5 mm. We demonstrated depth-of-interaction estimation capability through comparison of pinhole acquisitions with a point source on and off axes. Finally, a flood-corrected flood image exhibited a strip-level uniformity of less than 1%. This high-purity germanium offers many desirable properties for small-animal SPECT.

  16. Fabrication of novel cryomill for synthesis of high purity metallic nanoparticles

    NASA Astrophysics Data System (ADS)

    Kumar, Nirmal; Biswas, Krishanu

    2015-08-01

    The successful preparation of free standing metal nanoparticles with high purity in bulk quantity is the pre-requisite for any potential application. This is possible by using ball milling at cryogenic temperature. However, the most of ball mills available in the market do not allow preparing high purity metal nanoparticles by this route. In addition, it is not possible to carry out in situ measurements of process parameters as well as diagnostic of the process. In the present investigation, we present a detailed study on the fabrication of a cryomill, which is capable of avoiding contaminations in the product. It also provides in situ measurements and diagnostic of the low temperature milling process. Online monitoring of the milling temperature and observation of ball motion are the important aspects in the newly designed mill. The nanoparticles prepared using this fabricated mill have been found to be free standing and also free from contaminations.

  17. [Simultaneously preparation of grams of high purity tyrosol, crenulatin and salidroside from Rhodiola crenulata].

    PubMed

    Luo, Xin; Wang, Xue-jing; Li, Shi-ping; Zhang, Qiao; Zhao, Yi-wu; Huang Wen-zhe; Wang, Zhen-zhong; Xiao, Wei

    2015-04-01

    Tyrosol, crenulatin and salidroside are the main active constituents of Rhodiola crenulata, with extensive pharmacological activities. In the study, grams of high purity tyrosol, crenulatin and salidroside were simultaneously separated from R. crenulata by the first time. Firstly, R. crenulata was extracted by 70% alcohol. Then, with the yields of three compounds as the index, the macroporous resin was optimized. At last, grams of high purity tyrosol, crenulatin and salidroside were isolated by D-101 macroporousresin, purified by column chromatography. Detected by HPLC, the purity of three compounds were higher than 98%. This method has the advantages of simple process and operation, less dosage of organic solvent, highly yield and reproducibility, suitable for the simultaneously preparation of tyrosol, crenulatin and salidroside.

  18. Characterization of a high-purity germanium detector for small-animal SPECT

    PubMed Central

    Johnson, Lindsay C; Campbell, Desmond L; Hull, Ethan L; Peterson, Todd E

    2011-01-01

    We present an initial evaluation of a mechanically-cooled, high-purity germanium double-sided strip detector as a potential gamma camera for small-animal SPECT. It is 90 mm in diameter and 10 mm thick with two sets of 16 orthogonal strips that have a 4.5 mm width with a 5 mm pitch. We found an energy resolution of 0.96% at 140 keV, an intrinsic efficiency of 43.3% at 122 keV and a FWHM spatial resolution of approximately 1.5 mm. We demonstrated depth-of-interaction estimation capability through comparison of pinhole acquisitions with a point source on and off axis. Finally, a flood-corrected-flood image exhibited a strip-level uniformity of less than 1%. This high-purity germanium offers many desirable properties for small-animal SPECT. PMID:21852723

  19. A two-component system regulates gene expression of the type IX secretion component proteins via an ECF sigma factor

    PubMed Central

    Kadowaki, Tomoko; Yukitake, Hideharu; Naito, Mariko; Sato, Keiko; Kikuchi, Yuichiro; Kondo, Yoshio; Shoji, Mikio; Nakayama, Koji

    2016-01-01

    The periodontopathogen Porphyromonas gingivalis secretes potent pathogenic proteases, gingipains, via the type IX secretion system (T9SS). This system comprises at least 11 components; however, the regulatory mechanism of their expression has not yet been elucidated. Here, we found that the PorY (PGN_2001)-PorX (PGN_1019)-SigP (PGN_0274) cascade is involved in the regulation of T9SS. Surface plasmon resonance (SPR) analysis revealed a direct interaction between a recombinant PorY (rPorY) and a recombinant PorX (rPorX). rPorY autophosphorylated and transferred a phosphoryl group to rPorX in the presence of Mn2+. These results demonstrate that PorX and PorY act as a response regulator and a histidine kinase, respectively, of a two component system (TCS), although they are separately encoded on the chromosome. T9SS component-encoding genes were down-regulated in a mutant deficient in a putative extracytoplasmic function (ECF) sigma factor, PGN_0274 (SigP), similar to the porX mutant. Electrophoretic gel shift assays showed that rSigP bound to the putative promoter regions of T9SS component-encoding genes. The SigP protein was lacking in the porX mutant. Co-immunoprecipitation and SPR analysis revealed the direct interaction between SigP and PorX. Together, these results indicate that the PorXY TCS regulates T9SS-mediated protein secretion via the SigP ECF sigma factor. PMID:26996145

  20. Aluminium. II - A review of deformation properties of high purity aluminium and dilute aluminium alloys.

    NASA Technical Reports Server (NTRS)

    Reed, R. P.

    1972-01-01

    The elastic and plastic deformation behavior of high-purity aluminum and of dilute aluminum alloys is reviewed. Reliable property data, including elastic moduli, elastic coefficients, tensile, creep, fatigue, hardness, and impact are presented. Single crystal tensile results are discussed. Rather comprehensive reference lists, containing publications of the past 20 years, are included for each of the above categories. Defect structures and mechanisms responsible for mechanical behavior are presented. Strengthening techniques (alloys, cold work, irradiation, quenching, composites) and recovery are briefly reviewed.

  1. Diels-Alder reactions as an efficient route to high purity cyclic polymers.

    PubMed

    Glassner, Mathias; Blinco, James P; Barner-Kowollik, Christopher

    2011-05-18

    A simple and efficient route for the synthesis of cyclic polymer systems is presented. Linear furan protected α-maleimide-ω-cyclopentadienyl functionalized precursors (poly(methyl methacrylate) and poly(tert-butyl acrylate)) were synthesized via atom transfer radical polymerization (ATRP) and subsequent substitution of the bromine end-group with cyclopentadiene. Upon heating at high dilution, deprotection of the dieneophile occurs followed by an intramolecular Diels-Alder reaction yielding a high purity cyclic product.

  2. Synthesis and Characterization of High-Purity Tellurium Nanowires via Self-seed-Assisted Growth Approach

    NASA Astrophysics Data System (ADS)

    Li, Ying; Zhao, Wen-yu; Mu, Xin; Liu, Xing; He, Dan-qi; Zhu, Wan-ting; Zhang, Qing-jie

    2016-03-01

    Nanowires have attracted intense attention in recent years due to their novel physical properties. In this work, we prepare high-purity tellurium nanowires through the self-seed-assisted growth method previously developed by us. The tellurium seeds were firstly synthesized by reducing Na2TeO3 in the ice water with NaBH4. The high-purity tellurium nanowires with a diameter of 40-50 nm and a length of several tens of micrometers were then grown on tellurium seeds by reducing Na2TeO3 with hydrazine hydrate. X-ray diffraction, scanning electron microscopy and transmission electron microscopy were employed to characterize the crystal structure, microstructure, and growth direction of tellurium seeds and nanowires. The effects of temperature, time, surfactant and tellurium seeds on microstructures of tellurium nanowires has also been investigated. The synthesis conditions of tellurium seeds and nanowires was optimized. The selected area electron diffraction pattern confirms that the growth direction of tellurium nanowires is parallel to [0001] direction. It was discovered that high-purity tellurium nanowires with high aspect ratio can be synthesized by precisely controlling the temperature to adjust the nucleation rate of the tellurium nuclei, selecting the appropriate surfactant to induce the coordination along the macromolecular chain, and using tellurium seeds as the templates of the epitaxial growth of tellurium nuclei.

  3. Simple HPLC method for detection of trace ephedrine and pseudoephedrine in high-purity methamphetamine.

    PubMed

    Makino, Yukiko

    2012-03-01

    A simple and sensitive HPLC technique was developed for the qualitative determination of ephedrine and pseudoephedrine (ephedrines), used as precursors of clandestine d-methamphetamine hydrochloride of high purity. Good separation of ephedrines from bulk d-methamphetamine was achieved, without any extraction or derivatization procedure on a CAPCELLPACK C18 MGII (250 × 4.6 mm) column. The mobile phase consisted of 50 mM KH2 PO4-acetonitrile (94:6 v/v %) using an isocratic pump system within 20 min for detecting two analytes. One run took about 50 min as it was necessary to wash out overloaded methamphetamine for column conditioning. The analytes were detected by UV absorbance measurement at 210 nm. A sample (20 mg) was simply dissolved in 1 mL of water, and a 50 μL aliquot of the solution was injected into the HPLC. The detection limits for ephedrine and pseudoephedrine in bulk d-methamphetamine were as low as 3 ppm each. This analytical separation technique made it possible to detect ephedrine and/or pseudoephedrine in seven samples of high-purity d-methamphetamine hydrochloride seized in Japan. The presence of trace ephedrines in illicit methamphetamine may strongly indicate a synthetic route via ephedrine in methamphetamine profiling. This method is simple and sensitive, requiring only commonly available equipment, and should be useful for high-purity methamphetamine profiling.

  4. The prevalence of factor VIII and IX inhibitors among Saudi patients with hemophilia: Results from the Saudi national hemophilia screening program.

    PubMed

    Owaidah, Tarek; Momen, Abdulkareem Al; Alzahrani, Hazzaa; Almusa, Abdulrahman; Alkasim, Fawaz; Tarawah, Ahmed; Nouno, Randa Al; Batniji, Fatima Al; Alothman, Fahad; Alomari, Ali; Abu-Herbish, Saud; Abu-Riash, Mahmoud; Siddiqui, Khawar; Ahmed, Mansor; Mohamed, S Y; Saleh, Mahasen

    2017-01-01

    Hemophilia A and B are X-linked diseases that predominantly affect male patients. Patients can develop coagulation factor inhibitors, which exponentially increases the treatment cost. However, the prevalence of factor VIII and IX inhibitors in Saudi Arabia is unclear.This study aimed to determine the Saudi prevalence of factor VIII and IX inhibitors.This 4-year, 7-center, cross-sectional study evaluated the Saudi prevalences of hemophilia A and B. We collected the patients' clinical data, evaluated their disease, and tested for factor inhibitors.We included 202 patients with hemophilia (median age at diagnosis: 0.13 years, range: birth-34.8 years). The patients included 198 male patients (98%), 148 patients with hemophilia A (73.3%), and 54 patients with hemophilia B (26.7%). The patients exhibited severe factor VIII activity (<1%; 121 patients; 5.2%), moderate activity (1-5%; 7 patients; 4.9%), and mild activity (14 patients; 9.9%). Among the patients with care-related data, most patients were treated for episodic bleeding (76.8%) or received prophylaxis (22.6%); 1 patient received both treatments. Among the patients with source-related data, the factor replacements were derived from plasma (48.4%), recombinant concentrates (22.9%), both sources (14.6%), or fresh frozen plasma (14.1%). Factor VIII inhibitors were observed in 43 (29.3%) of the 147 patients, and only 1 of the 54 patients developed factor IX inhibitors. Most patients who developed inhibitors had severe hemophilia (40/44; 90.9%), and inhibitors were also common among patients who received recombinant products (14/43; 32.6%).The Saudi prevalence of factor inhibitors was similar to those among other ethnic populations.

  5. Recombinant factor IX (BAX326) in previously treated paediatric patients with haemophilia B: a prospective clinical trial.

    PubMed

    Urasinski, T; Stasyshyn, O; Andreeva, T; Rusen, L; Perina, F G; Oh, M S; Chapman, M; Pavlova, B G; Valenta-Singer, B; Abbuehl, B E

    2015-03-01

    A newly developed recombinant factor IX (BAX326(1) ) was investigated for prophylactic use in paediatric patients aged <12 years with severe (FIX level <1%) or moderately severe (FIX level 1-2%) haemophilia B. The aim of this prospective clinical trial was to assess the safety, haemostatic efficacy and pharmacokinetic profile of BAX326 in previously treated paediatric patients. BAX326 was administered as prophylaxis twice a week for a period of 6 months, and on demand for treatment of bleeds. Safety was assessed by the occurrence of related AEs, thrombotic events and immunologic assessments. Efficacy was evaluated by annualized bleeding rate (ABR), and by treatment response rating (excellent, good, fair, none). PK was assessed over 72 h. None of the 23 treated paediatric subjects had treatment-related SAEs or AEs. There were no thrombotic events, inhibitory or specific binding antibodies against FIX, rFurin or CHO protein. Twenty-six bleeds (19 non-joint vs. 7 joint bleeds) occurred (mean ABR 2.7 ± 3.14, median 2.0), of which 23 were injury-related. Twenty subjects (87%) did not experience any bleeds of spontaneous aetiology. Haemostatic efficacy of BAX326 was excellent or good for >96% of bleeds (100% of minor, 88.9% of moderate and 100% of major bleeds); the majority (88.5%) resolved after 1-2 infusions. Longer T1/2 and lower IR were observed in younger children (<6 years) compared to those aged 6 to 12 years. BAX326 administered as prophylactic treatment as well as for controlling bleeds is efficacious and safe in paediatric patients aged <12 years with haemophilia B.

  6. Thromboembolic complications associated with the use of prothrombin complex and factor IX concentrates.

    PubMed

    Köhler, M; Hellstern, P; Lechler, E; Uberfuhr, P; Müller-Berghaus, G

    1998-09-01

    In 1994, shortly after a heat-treated prothrombin complex concentrate (PCC) had been withdrawn from the German market due to transmission of hepatitis B, the license of another brand was withdrawn, due to 3 acute fatalities associated with the use of this product. We report on the clinical data of altogether 5 patients, who died during a 3 month period in Germany after having received this brand of PCC. All patients had surgery, acquired deficiencies of coagulation factors, and underlying diseases predisposing for thrombosis or disseminated intravascular coagulation. PCC was administered for the prevention of bleeding. In three patients, a drug interaction of PCC with aprotinin may also have played a role. Several points, however, are suspicious of a major causative effect of the respective product, (a) the close temporal correlation between administration of the drug and the subsequent clinical as well as laboratory deterioration, (b) the accumulation of these adverse events in a short period of time, when the use and market share of this brand increased due to the shortage of other products, and (c) laboratory abnormalities of this brand which have been consistently observed in several in vitro studies.

  7. Migration of grain boundaries and triple junctions in high-purity aluminum during annealing after slight cold rolling

    SciTech Connect

    Yin, Wenhong; Wang, Weiguo; Fang, Xiaoying; Qin, Congxiang; Xing, Xiaoguang

    2015-09-15

    Grain orientations and grain boundary migrations near triple junctions in a high purity aluminum were analyzed by electron back scattered diffraction. The results indicate that there are good correlations between the Schmid factors or Taylor factors and the misorientation values of point to original point in grains near the triple junctions in a slightly deformed sample. Grains with higher Schmid factors or lower Taylor factors typically correspond to higher misorientation values near the triple junctions. In a subsequent annealing at 400 °C, both grain boundaries and triple junctions migrate, but the former leave ghost lines. During such migration, a grain boundary grows from the grain with lower Schmid factor (higher Taylor factor) into the grain with higher Schmid factor (lower Taylor factor). Usually, the amount of migration of a grain boundary is considerably greater than that of a triple junction, and the grain boundary becomes more curved after migration. These observations indicate that the triple junctions have drag effects on grain boundary migration. - Highlights: • Polycrystalline aluminum with fine grains about 30 μm were used. • Off-line in situ EBSD was used to identify TJs before and after annealing. • Grains with higher SFs have higher misorientation values near TJs after deformation. • Grain boundaries grow from hard grains into soft grains during annealing. • Triple junctions have drag effects on grain boundaries migration.

  8. Dielectric Performance of a High Purity HTCC Alumina at High Temperatures - a Comparison Study with Other Polycrystalline Alumina

    NASA Technical Reports Server (NTRS)

    Chen, Liangyu

    2014-01-01

    A very high purity (99.99+%) high temperature co-fired ceramic (HTCC) alumina has recently become commercially available. The raw material of this HTCC alumina is very different from conventional HTCC alumina, and more importantly there is no glass additive in this alumina material for co-firing processing. Previously, selected HTCC and LTCC (low temperature co-fired ceramic) alumina materials were evaluated at high temperatures as dielectric and compared to a regularly sintered 96% polycrystalline alumina (96% Al2O3), where 96% alumina was used as the benchmark. A prototype packaging system based on regular 96% alumina with Au thickfilm metallization successfully facilitated long term testing of high temperature silicon carbide (SiC) electronic devices for over 10,000 hours at 500 C. In order to evaluate this new high purity HTCC alumina for possible high temperature packaging applications, the dielectric properties of this HTCC alumina substrate were measured and compared with those of 96% alumina and a previously tested LTCC alumina from room temperature to 550 C at frequencies of 120 Hz, 1 KHz, 10 KHz, 100 KHz, and 1 MHz. A parallel-plate capacitive device with dielectric of the HTCC alumina and precious metal electrodes were used for measurements of the dielectric constant and dielectric loss of the co-fired alumina material in the temperature and frequency ranges. The capacitance and AC parallel conductance of the capacitive device were directly measured by an AC impedance meter, and the dielectric constant and parallel AC conductivity of the dielectric were calculated from the capacitance and conductance measurement results. The temperature and frequency dependent dielectric constant, AC conductivity, and dissipation factor of the HTCC alumina substrate are presented and compared to those of 96% alumina and a selected LTCC alumina. Other technical advantages of this new co-fired material for possible high packaging applications are also discussed.

  9. Title IX Resource Guide

    ERIC Educational Resources Information Center

    Office for Civil Rights, US Department of Education, 2015

    2015-01-01

    Title IX of the Education Amendments of 1972 (Title IX) prohibits discrimination based on sex in education programs and activities in federally funded schools at all levels. If any part of a school district or college receives any Federal funds for any purpose, all of the operations of the district or college are covered by Title IX. The essence…

  10. Factor IX assay

    MedlinePlus

    ... P, Lillicrap D. Hemophilia A and B. In: Hoffman R, Benz EJ Jr, Silberstein LE, Heslop HE, ... Laboratory evaluation of hemostatic and thrombotic disorders. In: Hoffman R, Benz EJ Jr, Silberstein LE, Heslop HE, ...

  11. Understanding Friction and Wear Mechanisms of High-Purity Titanium against Steel in Liquid Nitrogen Temperature

    NASA Astrophysics Data System (ADS)

    Basu, Bikramjit; Sarkar, J.; Mishra, Ravi

    2009-02-01

    Although the friction and wear properties of several metallic alloys in unlubricated conditions are widely investigated, such understanding for high-purity metals in cryogenic environment is rather limited. This article reports the tribological properties of high-purity α-titanium ( α-Ti), prepared by cold rolling and recrystallization annealing, under liquid nitrogen (LN2) and room temperature (RT) environments against steel (bearing grade: SAE 52100) at varying loads (up to 15 N) and sliding speeds (0.6 to 4.19 m/s). It has been found that the steady-state coefficient of friction (COF) of titanium under LN2 environment (˜0.27 to 0.33) is lower than that at RT COF (˜0.33 to 0.58) irrespective of sliding speed. For cryogenic sliding conditions, the COF decreased steadily with sliding speed to a mean value of about 0.28 and no appreciable variation in COF is noticed for sliding speed of more than 1.5 m/s. The wear rate under both environment conditions was of the order of 10-3 mm3 N-1 m-1 irrespective of variation in operating parameters, but the RT wear rate was found to be higher compared to the LN2 case. Overall, the experimental results demonstrate improved tribological properties of high-purity titanium at LN2 temperature compared to the RT. Flow localization at tribological interfaces because of the large strain rate and subsequent damage accumulation at the titanium test piece are some of the attributes of the wear of Ti at LN2 temperature. In addition, the galling of titanium was also observed to occur under large contact stress and sliding speed conditions.

  12. High Purity Americium-241 for Fuel Cycle R&D Program

    SciTech Connect

    Dr. Paul A. Lessing

    2011-07-01

    Previously the U.S. Department of Energy released Am-241 for various applications such as smoke detectors and Am-Be neutron sources for oil wells. At this date there is a shortage of usable, higher purity Am-241 in metal and oxide form available in the United States. Recently, the limited source of Am-241 has been from Russia with production being contracted to existing customers. The shortage has resulted in the price per gram rising dramatically over the last few years. DOE-NE currently has need for high purity Am-241 metal and oxide to fabricate fuel pellets for reactor testing in the Fuel Cycle R&D program. All the available high purity americium has been gathered from within the DOE system of laboratories. However, this is only a fraction of the projected needs of FCRD over the next 10 years. Therefore, FCR&D has proposed extraction and purification concepts to extract Am-241 from a mixed AmO2-PuO2 feedstock stored at the Savannah River Site. The most simple extraction system is based upon high temperature reduction using lanthanum metal with concurrent evaporation and condensation to produce high purity Am metal. Metallic americium has over a four order of magnitude higher vapor pressure than plutonium. Results from small-scale reduction experiments are presented. These results confirm thermodynamic predictions that at 1000 deg C metallic lanthanum reduces both PuO2 and AmO2. Faster kinetics are expected for temperatures up to about 1500 deg C.

  13. Compensation Mechanism in High Purity Semi-Insulating 4H-SiC

    DTIC Science & Technology

    2007-01-01

    online 15 March 2007 A study of deep levels in high purity semi-insulating 4H-SiC has been made using temperature dependent Hall effect TDH , thermal and...optical admittance spectroscopies, and secondary ion mass spectrometry SIMS. Thermal activation energies from TDH varied from a low of 0.55 eV to a...high of 1.65 eV. All samples studied showed n-type conduction with the Fermi level in the upper half of the band gap. Fits of the TDH data to

  14. Formation of High-Purity Indium Oxide Nanoparticles and Their Application to Sensitive Detection of Ammonia

    PubMed Central

    Bhardwaj, Sanjeev K.; Bhardwaj, Neha; Kukkar, Manil; Sharma, Amit L.; Kim, Ki-Hyun; Deep, Akash

    2015-01-01

    High-purity In2O3 nanoparticles were recovered from scrap indium tin oxide substrates in a stepwise process involving acidic leaching, liquid-liquid extraction with a phosphine oxide extractant, and combustion of the organic phase. The morphological and structural parameters of the recovered nanoparticles were investigated to support the formation of the desired products. These In2O3 nanoparticles were used for sensitive sensing of ammonia gas using a four-probe electrode device. The proposed sensor offered very quick response time (around 10 s) and highly sensitive detection of ammonia (at a detection limit of 1 ppm). PMID:26694415

  15. High-precision efficiency calibration of a high-purity co-axial germanium detector

    NASA Astrophysics Data System (ADS)

    Blank, B.; Souin, J.; Ascher, P.; Audirac, L.; Canchel, G.; Gerbaux, M.; Grévy, S.; Giovinazzo, J.; Guérin, H.; Nieto, T. Kurtukian; Matea, I.; Bouzomita, H.; Delahaye, P.; Grinyer, G. F.; Thomas, J. C.

    2015-03-01

    A high-purity co-axial germanium detector has been calibrated in efficiency to a precision of about 0.15% over a wide energy range. High-precision scans of the detector crystal and γ-ray source measurements have been compared to Monte-Carlo simulations to adjust the dimensions of a detector model. For this purpose, standard calibration sources and short-lived online sources have been used. The resulting efficiency calibration reaches the precision needed e.g. for branching ratio measurements of super-allowed β decays for tests of the weak-interaction standard model.

  16. High-purity cobalt thin films with perpendicular magnetic anisotropy prepared by chemical vapor deposition

    NASA Astrophysics Data System (ADS)

    Ootera, Yasuaki; Shimada, Takuya; Kado, Masaki; Quinsat, Michael; Morise, Hirofumi; Nakamura, Shiho; Kondo, Tsuyoshi

    2015-11-01

    A study of the chemical vapor deposition (CVD) of high-purity cobalt thin films is described. The Co layer prepared by a thermal CVD technique with a Pt/Ta underlayer and a Pt cap layer shows a saturation magnetization (Ms) of ∼1.8 T and perpendicular magnetic anisotropy (PMA) with an anisotropy energy (Ku) of ∼105 J/m3. The cobalt thickness dependence of Ku reveals that the interfacial anisotropy at the Pt/Co interface is most likely the origin of the obtained PMA.

  17. Formation and evolution of tweed structures on high-purity aluminum polycrystalline foils under cyclic tension

    SciTech Connect

    Kuznetsov, P. V.; Vlasov, I. V.; Sklyarova, E. A.; Smekalina, T. V.

    2015-10-27

    Peculiarities of formation and evolution of tweed structures on the surface of high-purity aluminum polycrystalline foils under cyclic tension were studied using an atom force microscope and a white light interferometer. Tweed structures of micron and submicron sizes were found on the foils at different number of cycles. In the range of 42,000 < N < 95,000 cycles destruction of tweed patterns is observed, which leads to their disappearance from the surface of the foils. Formation of tweed structures of various scales is discussed in terms of the Grinfeld instability.

  18. Corrosion behavior of surface films on boron-implanted high purity iron and stainless steels

    NASA Technical Reports Server (NTRS)

    Kim, H. J.; Carter, W. B.; Hochman, R. F.; Meletis, E. I.

    1985-01-01

    Boron (dose, 2 x 10 to the 17th ions/sq cm) was implanted into high purity iron, AISI 316 austenitic stainless steel, and AISI 440C martensitic stainless steel, at 40 keV. The film structure of implanted samples was examined and characterized by contrast and diffraction analyses utilizing transmission electron microscopy. The effect of B(+) ion implantation on the corrosion behavior was studied using the potentiodynamic polarization technique. Tests were performed in deaerated 1 N H2SO4 and 0.1 M NaCl solutions. Scanning electron microscopy was used to examine the morphology of the corroded surfaces after testing.

  19. Preliminary study on non-viral transfection of F9 (factor IX) gene by nucleofection in human adipose-derived mesenchymal stem cells

    PubMed Central

    Olmedillas López, Susana; Garcia-Arranz, Mariano; Garcia-Olmo, Damian

    2016-01-01

    Background. Hemophilia is a rare recessive X-linked disease characterized by a deficiency of coagulation factor VIII or factor IX. Its current treatment is merely palliative. Advanced therapies are likely to become the treatment of choice for the disease as they could provide a curative treatment. Methods. The present study looks into the use of a safe non-viral transfection method based on nucleofection to express and secrete human clotting factor IX (hFIX) where human adipose tissue derived mesenchymal stem cells were used as target cells in vitro studies and NOD. Cg-Prkdcscid Il2rgtm1Wjl/SzJ mice were used to analyze factor IX expression in vivo studies. Previously, acute liver injury was induced by an injected intraperitoneal dose of 500 mg/kg body weight of acetaminophen. Results. Nucleofection showed a percentage of positive cells ranging between 30.7% and 41.9% and a cell viability rate of 29.8%, and cells were shown to secrete amounts of hFIX between 36.8 and 71.9 ng/mL. hFIX levels in the blood of NSG mice injected with ASCs transfected with this vector, were 2.7 ng/mL 48 h after injection. Expression and secretion of hFIX were achieved both in vitro cell culture media and in vivo in the plasma of mice treated with the transfected ASCs. Such cells are capable of eventually migrating to a previously damaged target tissue (the liver) where they secrete hFIX, releasing it to the bloodstream over a period of at least five days from administration. Conclusions. The results obtained in the present study may form a preliminary basis for the establishment of a future ex vivo non-viral gene/cellular safe therapy protocol that may eventually contribute to advancing the treatment of hemophilia. PMID:27114871

  20. Protein modification during anti-viral heat-treatment bioprocessing of factor VIII concentrates, factor IX concentrates, and model proteins in the presence of sucrose.

    PubMed

    Smales, C Mark; Pepper, Duncan S; James, David C

    2002-01-05

    To ensure the optimal safety of plasma derived and new generation recombinant proteins, heat treatment is customarily applied in the manufacturing of such biopharmaceuticals as a means of viral inactivation. In subjecting proteins to anti-viral heat-treatment it is necessary to use high concentrations of thermostabilizing excipients to prevent protein damage, and it is therefore imperative that the correct balance between bioprocessing conditions, maintenance of protein integrity and virus kill is found. In this study we have utilized model proteins (lysozyme, fetuin, and human serum albumin) and plasma-derived therapeutic proteins (factor VIII and factor IX) to investigate the protein modifications that occur during anti-viral heat treatment. Specifically, we investigated the relationship between bioprocessing conditions and the type and extent of protein modification under a variety of industrially relevant wet and lyophilized heat treatments using sucrose as a thermostabilizing agent. Heat treatment led to the formation of disulfide crosslinks and aggregates in proteins containing free cysteine residues. Terminal oligosaccharide sialic acid residues were hydrolyzed from the glycan moieties of glycoproteins during anti-viral heat treatment. Heat treatment promoted sucrose hydrolysis to yield glucose and fructose, leading, in turn, to the glycation of lysine amino groups in those proteins containing di-lysine motifs. During extended hear treatments, 1,2-dicarbonyl type advanced glycation end-products were also formed. Glycation-type modifications were more prevalent in wet heat-treated protein formulations.

  1. Confirmation of warfarin resistance of naturally occurring VKORC1 variants by coexpression with coagulation factor IX and in silico protein modelling

    PubMed Central

    2014-01-01

    Background VKORC1 has been identified some years ago as the gene encoding vitamin K epoxide reductase (VKOR) – the target protein for coumarin derivates like warfarin or phenprocoumon. Resistance against warfarin and other coumarin-type anticoagulants has been frequently reported over the last 50 years in rodents due to problems in pest control as well as in thrombophilic patients showing variable response to anticoagulant treatment. Many different mutations have already been detected in the VKORC1 gene leading to warfarin resistance in rats, mice and in humans. Since the conventional in vitro dithiothreitol (DTT)-driven VKOR enzymatic assay often did not reflect the in vivo status concerning warfarin resistance, we recently developed a cell culture-based method for coexpression of VKORC1 with coagulation factor IX and subsequent measurement of secreted FIX in order to test warfarin inhibition in wild-type and mutated VKORC1. Results In the present study, we coexpressed wild-type factor IX with 12 different VKORC1 variants which were previously detected in warfarin resistant rats and mice. The results show that amino acid substitutions in VKORC1 maintain VKOR activity and are associated with warfarin resistance. When we projected in silico the amino acid substitutions onto the published three-dimensional model of the bacterial VKOR enzyme, the predicted effects matched well the catalytic mechanism proposed for the bacterial enzyme. Conclusions The established cell-based system for coexpression of VKORC1 and factor IX uses FIX activity as an indicator of carboxylation efficiency. This system reflects the warfarin resistance status of VKORC1 mutations from anticoagulant resistant rodents more closely than the traditional DTT-driven enzyme assay. All mutations studied were also predicted to be involved in the reaction mechanism. PMID:24491178

  2. Secondary electron emission characteristics of ion-textured copper and high-purity isotropic graphite surfaces

    NASA Technical Reports Server (NTRS)

    Curren, A. N.; Jensen, K. A.

    1984-01-01

    Experimentally determined values of true secondary electron emission and relative values of reflected primary electron yield for untreated and ion textured oxygen free high conductivity copper and untreated and ion textured high purity isotropic graphite surfaces are presented for a range of primary electron beam energies and beam impingement angles. This investigation was conducted to provide information that would improve the efficiency of multistage depressed collectors (MDC's) for microwave amplifier traveling wave tubes in space communications and aircraft applications. For high efficiency, MDC electrode surfaces must have low secondary electron emission characteristics. Although copper is a commonly used material for MDC electrodes, it exhibits relatively high levels of secondary electron emission if its surface is not treated for emission control. Recent studies demonstrated that high purity isotropic graphite is a promising material for MDC electrodes, particularly with ion textured surfaces. The materials were tested at primary electron beam energies of 200 to 2000 eV and at direct (0 deg) to near grazing (85 deg) beam impingement angles. True secondary electron emission and relative reflected primary electron yield characteristics of the ion textured surfaces were compared with each other and with those of untreated surfaces of the same materials. Both the untreated and ion textured graphite surfaces and the ion treated copper surface exhibited sharply reduced secondary electron emission characteristics relative to those of untreated copper. The ion treated graphite surface yielded the lowest emission levels.

  3. Surface preparation for high purity alumina ceramics enabling direct brazing in hydrogen atmospheres

    DOEpatents

    Cadden, Charles H.; Yang, Nancy Yuan Chi; Hosking, Floyd M.

    2001-01-01

    The present invention relates to a method for preparing the surface of a high purity alumina ceramic or sapphire specimen that enables direct brazing in a hydrogen atmosphere using an active braze alloy. The present invention also relates to a method for directly brazing a high purity alumina ceramic or sapphire specimen to a ceramic or metal member using this method of surface preparation, and to articles produced by this brazing method. The presence of silicon, in the form of a SiO.sub.2 -containing surface layer, can more than double the tensile bond strength in alumina ceramic joints brazed in a hydrogen atmosphere using an active Au-16Ni-0.75 Mo-1.75V filler metal. A thin silicon coating applied by PVD processing can, after air firing, produce a semi-continuous coverage of the alumina surface with a SiO.sub.2 film. Room temperature tensile strength was found to be proportional to the fraction of air fired surface covered by silicon-containing films. Similarly, the ratio of substrate fracture versus interface separation was also related to the amount of surface silicon present prior to brazing. This process can replace the need to perform a "moly-manganese" metallization step.

  4. Streamer knotwilg branching: sudden transition in morphology of positive streamers in high-purity nitrogen

    NASA Astrophysics Data System (ADS)

    Heijmans, L. C. J.; Clevis, T. T. J.; Nijdam, S.; van Veldhuizen, E. M.; Ebert, U.

    2015-09-01

    We describe a peculiar branching phenomenon in positive repetitive streamer discharges in high purity nitrogen. We name it knotwilg branching after the Dutch word for a pollard willow tree. In a knotwilg branching a thick streamer suddenly splits into many thin streamers. Under some conditions this happens for all streamers in a discharge at about the same distance from the high-voltage electrode tip. At this distance, the thick streamers suddenly bend sharply and appear to propagate over a virtual surface surrounding the high-voltage electrode, rather than following the background electric field lines. From these bent thick streamers many, much thinner, streamers emerge that roughly follow the background electric field lines, creating the characteristic knotwilg branching. We have only found this particular morphology in high purity nitrogen at pressures in the range 50 to 200 mbar and for pulse repetition rates above 1 Hz; the experiments were performed for an electrode distance of 16 cm and for fast voltage pulses of 20 or 30 kV. These observations clearly disagree with common knowledge on streamer propagation. We have analyzed the data of several tens of thousands of discharges to clarify the phenomena. We also present some thoughts on how the ionization of the previous discharges could concentrate into some pre-ionization region near the needle electrode and create the knotwilg morphology, but we present no final explanation.

  5. Recovery of high purity sulfuric acid from the waste acid in toluene nitration process by rectification.

    PubMed

    Song, Kai; Meng, Qingqiang; Shu, Fan; Ye, Zhengfang

    2013-01-01

    Waste sulfuric acid is a byproduct generated from numerous industrial chemical processes. It is essential to remove the impurities and recover the sulfuric acid from the waste acid. In this study the rectification method was introduced to recover high purity sulfuric acid from the waste acid generated in toluene nitration process by using rectification column. The waste acid quality before and after rectification were evaluated using UV-Vis spectroscopy, GC/MS, HPLC and other physical and chemical analysis. It was shown that five nitro aromatic compounds in the waste acid were substantially removed and high purity sulfuric acid was also recovered in the rectification process at the same time. The COD was removed by 94% and the chrominance was reduced from 1000° to 1°. The recovered sulfuric acid with the concentration reaching 98.2 wt% had a comparable quality with commercial sulfuric acid and could be recycled back into the toluene nitration process, which could avoid waste of resources and reduce the environmental impact and pollution.

  6. Preparation and Evaluation of High-Purity La2O3

    NASA Astrophysics Data System (ADS)

    Lee, Gwang Seop; Uchikoshi, Masahito; Mimura, Kouji; Isshiki, Minoru

    2010-06-01

    A separation procedure based on extraction chromatography using the di(2-ethylhexyl) phosphoric acid (D2EHPA) impregnated resin, anion exchange with DIAION SA 10 resin, and oxalate precipitation has been developed for the preparation of high-purity La2O3 in hydrochloric acid media at a high La concentration. The metallic impurities Ce, Pr, Nd, Sm, K, Mg, Ca, Zn, Cu, Co, Mn, Pb, Al, In, and Fe, but not Bi, were removed efficiently from La by extraction chromatography using a D2EHPA impregnated resin. The Bi was separated from the La by anion exchange (DIAION SA 10) separation. Thus, a high-purity LaCl3 solution was obtained by anion exchange separation and extraction chromatography. La2O3 was prepared from the purified LaCl3 solution by oxalate precipitation. Glow discharge mass spectrometry was applied for purity evaluation of the prepared La2O3. The purity of the prepared La2O3 was more than 99.9998 pct total rare earth oxide.

  7. Photoconductive response of compensating impurities in photothermal ionization spectroscopy of high-purity silicon and germanium

    SciTech Connect

    Darken, L.S.; Hyder, S.A.

    1983-04-15

    In photothermal ionization spectroscopy both positive and negative photoconductivity responses have been reported from compensating centers neutralized by minority carriers generated by band-edge light. Here, the response of compensating impurities in both n-type and p-type high-purity (Vertical BarN/sub A/-N/sub D/Vertical Bar roughly-equal10/sup 10/--10/sup 12/ cm/sup -3/) nuclear-detector-grade silicon and germanium is reported. Negative photoconductive responses from compensating impurities were observed only when the distance the photothermally generated majority carriers traveled before recapture by shallow levels was longer than the sample length (contact to contact). We propose that in high-purity semiconductors, such as used in this study, it is the contact configuration that is responsible for the apparent rapid recombination of minority carriers which causes negative minority-carrier photoconductivity. n/sup +/nn/sup +/ or p/sup +/pp/sup +/ structures allow multiple traversals through the sample by only majority carriers. The dependence of the band-edge light generated excess carrier density on applied electric field supports this mechanism.

  8. Process for producing high purity isoolefins and dimers thereof by dissociation of ethers

    DOEpatents

    Smith, Jr., Lawrence A.; Jones, Jr., Edward M.; Hearn, Dennis

    1984-01-01

    Alkyl tertiary butyl ether or alkyl tertiary amyl ether is dissociated by vapor phase contact with a cation acidic exchange resin at temperatures in the range of 150.degree. to 250.degree. F. at LHSV of 0.1 to 20 to produce a stream consisting of unreacted ether, isobutene or isoamylene and an alcohol corresponding to the alkyl radical. After the alcohol is removed, the ether/isoolefin stream may be fractionated to obtain a high purity isoolefin (99+%) or the ether/isoolefin stream can be contacted in liquid phase with a cation acidic exchange resin to selectively dimerize the isoolefin in a highly exothermic reaction, followed by fractionation of the dimerization product to produce high purity diisoolefin (97+%). In the case where the alkyl is C.sub.3 to C.sub.6 and the corresponding alcohol is produced on dissociation of the ether, combined dissociation-distillation may be carried out such that isoolefin is the overhead product and alcohol the bottom.

  9. Process for producing high purity isoolefins and dimers thereof by dissociation of ethers

    DOEpatents

    Smith, L.A. Jr.; Jones, E.M. Jr.; Hearn, D.

    1984-05-08

    Alkyl tertiary butyl ether or alkyl tertiary amyl ether is dissociated by vapor phase contact with a cation acidic exchange resin at temperatures in the range of 150 to 250 F at LHSV of 0.1 to 20 to produce a stream consisting of unreacted ether, isobutene or isoamylene and an alcohol corresponding to the alkyl radical. After the alcohol is removed, the ether/isoolefin stream may be fractionated to obtain a high purity isoolefin (99+%) or the ether/isoolefin stream can be contacted in liquid phase with a cation acidic exchange resin to selectively dimerize the isoolefin in a highly exothermic reaction, followed by fractionation of the dimerization product to produce high purity diisoolefin (97+%). In the case where the alkyl is C[sub 3] to C[sub 6] and the corresponding alcohol is produced on dissociation of the ether, combined dissociation-distillation may be carried out such that isoolefin is the overhead product and alcohol the bottom. 2 figs.

  10. Recycling of high purity selenium from CIGS solar cell waste materials.

    PubMed

    Gustafsson, Anna M K; Foreman, Mark R StJ; Ekberg, Christian

    2014-10-01

    Copper indium gallium diselenide (CIGS) is a promising material in thin film solar cell production. To make CIGS solar cells more competitive, both economically and environmentally, in comparison to other energy sources, methods for recycling are needed. In addition to the generally high price of the material, significant amounts of the metals are lost in the manufacturing process. The feasibility of recycling selenium from CIGS through oxidation at elevated temperatures was therefore examined. During oxidation gaseous selenium dioxide was formed and could be separated from the other elements, which remained in solid state. Upon cooling, the selenium dioxide sublimes and can be collected as crystals. After oxidation for 1h at 800°C all of the selenium was separated from the CIGS material. Two different reduction methods for reduction of the selenium dioxide to selenium were tested. In the first reduction method an organic molecule was used as the reducing agent in a Riley reaction. In the second reduction method sulphur dioxide gas was used. Both methods resulted in high purity selenium. This proves that the studied selenium separation method could be the first step in a recycling process aimed at the complete separation and recovery of high purity elements from CIGS.

  11. Solution and slurry sampling electrothermal atomic absorption spectrometry for the analysis of high purity quartz

    NASA Astrophysics Data System (ADS)

    Hauptkorn, Susanne; Krivan, Viliam

    1996-07-01

    A slurry sampling electrothermal atomic absorption spectrometry (ETAAS) method for the determination of Al, Cr, Cu, Fe, K, Li, Mg, Mn and Na at trace and ultratrace level in high purity quartz samples has been developed. The influence of atomization temperature, internal gas flow during atomization and carbide modification of the graphite tube on the background absorption has been studied. Simple quantification via calibration curves, recorded with aqueous standards, is possible for all elements except Al. The performance and the accuracy of the slurry sampling technique are compared to those of the analysis of hydrofluoric acid digests. With both methods, the blanks could be substantially reduced by minimization of sample handling. Because of essentially higher applicable sample portions, the solution technique provides lower limits of detection for all elements excluding Al, Na and K. For the slurry sampling technique, the achievable limits of detection are in the range of 2 (Mg) to 500 (Fe) ng g -1 and for the solution technique, they are between 0.4 (Mg) and 500 (Al) ng g -1. Thus, both developed methods are well suited for ultratrace analysis of high purity quartz for microelectronic applications. The results obtained by these two ETAAS techniques are compared with those of independent methods including neutron activation analysis.

  12. Process for producing high purity silicon nitride by the direct reaction between elemental silicon and nitrogen-hydrogen liquid reactants

    DOEpatents

    Pugar, Eloise A.; Morgan, Peter E. D.

    1990-01-01

    A process is disclosed for producing, at a low temperature, a high purity reaction product consisting essentially of silicon, nitrogen, and hydrogen which can then be heated to produce a high purity alpha silicon nitride. The process comprises: reacting together a particulate elemental high purity silicon with a high purity nitrogen-hydrogen reactant in its liquid state (such as ammonia or hydrazine) having the formula: N.sub.n H.sub.(n+m) wherein: n=1-4 and m=2 when the nitrogen-hydrogen reactant is straight chain, and 0 when the nitrogen-hydrogen reactant is cyclic. High purity silicon nitride can be formed from this intermediate product by heating the intermediate product at a temperature of from about 1200.degree.-1700.degree. C. for a period from about 15 minutes up to about 2 hours to form a high purity alpha silicon nitride product. The discovery of the existence of a soluble Si-N-H intermediate enables chemical pathways to be explored previously unavailable in conventional solid state approaches to silicon-nitrogen ceramics.

  13. Process for producing high purity silicon nitride by the direct reaction between elemental silicon and nitrogen-hydrogen liquid reactants

    DOEpatents

    Pugar, E.A.; Morgan, P.E.D.

    1987-09-15

    A process is disclosed for producing, at a low temperature, a high purity reaction product consisting essentially of silicon, nitrogen, and hydrogen which can then be heated to produce a high purity alpha silicon nitride. The process comprises: reacting together a particulate elemental high purity silicon with a high purity nitrogen-hydrogen reactant in its liquid state (such as ammonia or hydrazine) having the formula: N/sub n/H/sub (n+m)/ wherein: n = 1--4 and m = 2 when the nitrogen-hydrogen reactant is straight chain, and 0 when the nitrogen-hydrogen reactant is cyclic. High purity silicon nitride can be formed from this intermediate product by heating the intermediate product at a temperature of from about 1200--1700/degree/C for a period from about 15 minutes up to about 2 hours to form a high purity alpha silicon nitride product. The discovery of the existence of a soluble Si/endash/N/endash/H intermediate enables chemical pathways to be explored previously unavailable in conventional solid-state approaches to silicon-nitrogen ceramics

  14. Efficient purification of high-purity compounds from the stem of Lonicera japonica Thunb using two-dimensional preparative chromatography.

    PubMed

    Jin, Hongli; Liu, Yanfang; Feng, Jiatao; Guo, Zhimou; Wang, Chaoran; Zhong, Zhengsheng; Peng, Xiaojun; Dang, Jun; Tao, Yanduo; Liang, Xinmiao

    2013-08-01

    Purification of high-purity compounds from traditional Chinese medicines (TCMs) plays an important role in investigating their bioactivity. Nevertheless, it is often quite difficult to isolate compounds with high purity because of the complexity of TCMs in chemical composition. In this work, a two-dimensional preparation method was successfully developed for the preparation of high-purity compounds from the stem of Lonicera japonica Thunb, based on two novel polar copolymerized RP stationary phases, XAqua C3 and XAqua C18. An XAqua C3 prep column was used to separate the sample in the first-dimensional preparation, and 14 g of sample was fractionated into eight fractions with a recovery of 82%. An XAqua C18 prep column was selected to prepare high-purity compounds in the second-dimensional preparation for its good orthogonality with the XAqua C3 stationary phase. As a result, major compounds in the sample were isolated with more than 99% purity. This method is a potent method to realize the efficient purification of compounds with high purity from the stem of L. japonica Thunb and it shows great potential in the separation of high-purity compounds from complex samples.

  15. Evolutionary pattern of mutation in the factor IX genes of great apes: How does it compare to the pattern of recent germline mutation in patients with hemophilia B?

    SciTech Connect

    Grouse, L.H.; Ketterling, R.P.; Sommer, S.S.

    1994-09-01

    Most mutations causing hemophilia B have arisen within the past 150 years. By correcting for multiple biases, the underlying rates of spontaneous germline mutation have been estimated in the factor IX gene. From these rates, an underlying pattern of mutation has emerged. To determine if this pattern compares to a underlying pattern found in the great apes, sequence changes were determined in intronic regions of the factor IX gene. The following species were studied: Gorilla gorilla, Pan troglodytes (chimpanzee), Pongo pygmacus (orangutan) and Homo sapiens. Intronic sequences at least 200 bp from a splice junction were randomly chosen, amplified by cross-species PCR, and sequenced. These regions are expected to be subject to little if any selective pressure. Early diverged species of Old World monkeys were also studied to help determine the direction of mutational changes. A total of 62 sequence changes were observed. Initial data suggest that the average pattern since evolution of the great apes has a paucity of transitions at CpG dinucleotides and an excess of microinsertions to microdeletions when compared to the pattern observed in humans during the past 150 years (p<.05). A larger study is in progress to confirm these results.

  16. Production of carbon monoxide-free hydrogen and helium from a high-purity source

    DOEpatents

    Golden, Timothy Christopher; Farris, Thomas Stephen

    2008-11-18

    The invention provides vacuum swing adsorption processes that produce an essentially carbon monoxide-free hydrogen or helium gas stream from, respectively, a high-purity (e.g., pipeline grade) hydrogen or helium gas stream using one or two adsorber beds. By using physical adsorbents with high heats of nitrogen adsorption, intermediate heats of carbon monoxide adsorption, and low heats of hydrogen and helium adsorption, and by using vacuum purging and high feed stream pressures (e.g., pressures of as high as around 1,000 bar), pipeline grade hydrogen or helium can purified to produce essentially carbon monoxide -free hydrogen and helium, or carbon monoxide, nitrogen, and methane-free hydrogen and helium.

  17. Effect of Sintering Temperature on the Synthesis of High Purity Cordierite

    NASA Astrophysics Data System (ADS)

    Choo, Y. P.; Chow, T. Y.; Mohamad, H.

    2008-03-01

    Cordierite is silicate material widely used in ceramic industry. The effect of sintering temperature to the properties of cordierite by sol gel method was studied with utilizing magnesium nitrate, aluminum nitrate, ethanol, and tetraethyl orthosilicate (TEOS) as starting materials. Gels are dried and sintered at different temperature (1000 °C, 1200 °C, 1300 °C and 1350 °C) then characterized by varies analysis techniques. XRD analysis shows that spinel, μ-cordierite and cristobalite are formed at 1000 °C which spinel as predominant phase. At 1200 °C, μ-cordierite occured as predominant phase, spinel, sapphirine and cristobalite are formed as minor phases. It also confirmed that high purity α-cordierite formed at 1300 °C and clearly observed at 1350 °C. Result of EDX analysis proved that magnesium, aluminum, silicon and oxygen was existed in the cordierite.

  18. Annealing Behavior at Triple Junctions in High-Purity Aluminum After Slight Cold Rolling

    NASA Astrophysics Data System (ADS)

    Yin, Wenhong; Wang, Weiguo; Fang, Xiaoying; Qin, Congxiang

    2017-02-01

    High-purity polycrystalline aluminum samples with a typical grain size of approximately 30 μm were slightly cold-rolled with a thickness reduction of 15%, and then, off-line in situ electron backscatter diffraction was used to identify the annealing behavior at triple junctions during annealing at 400 °C. The results show that recrystallization nuclei are developed at some triple junctions during annealing. High-angle grain boundaries migrate from harder grains to softer grains at the triple junctions leading to the formation of nuclei. All such nuclei show Σ3 orientation relationships with the parent grains, and the bounded Σ3 boundaries are found to be incoherent. During further annealing, these nuclei are consumed by other growing grains, indicating that their presence is just a release of the strain concentration at the triple junctions.

  19. In-growth of an electrically active defect in high-purity silicon after proton irradiation

    SciTech Connect

    Nylandsted Larsen, A.; Juul Pedersen, H.; Christian Petersen, M.; Privitera, V.; Gurimskaya, Y.; Mesli, A.

    2013-12-14

    Defect-related energy levels in the lower half of the band gap of silicon have been studied with transient-capacitance techniques in high-purity, carbon and oxygen lean, plasma-enhanced chemical-vapor deposition grown, n-and p-type silicon layers after 2-MeV proton irradiations at temperatures at or just below room temperature. The in-growth of a distinct line in deep-level transient spectroscopy spectra, corresponding to a level in the band gap at E{sub V} + 0.357 eV where E{sub V} is the energy of the valence band edge, takes place for anneal temperatures at around room temperature with an activation energy of 0.95 ± 0.08 eV. The line disappears at an anneal temperature of around 450 K. The corresponding defect is demonstrated not to contain boron, carbon, oxygen, or phosphorus. Possible defect candidates are discussed.

  20. Application of Thermodynamic Calculations to the Pyro-refining Process for Production of High Purity Bismuth

    NASA Astrophysics Data System (ADS)

    Mezbahul-Islam, Mohammad; Belanger, Frederic; Chartrand, Patrice; Jung, In-Ho; Coursol, Pascal

    2017-02-01

    The present work has been performed with the aim to optimize the existing process for the production of high purity bismuth (99.999 pct). A thermo-chemical database including most of the probable impurities of bismuth (Bi-X, X = Ag, Au, Al, Ca, Cu, Fe, Mg, Mn, Na, Ni, Pb, S, Sb, Sn, Si, Te, Zn) has been constructed to perform different thermodynamic calculations required for the refining process. Thermodynamic description for eight of the selected binaries, Bi-Ca, Cu, Mn, Ni, Pb, S, Sb, and Sn, has been given in the current paper. Using the current database, different thermodynamic calculations have been performed to explain the steps involved in the bismuth refining process.

  1. Efficient single photon emission from a high-purity hexagonal boron nitride crystal

    NASA Astrophysics Data System (ADS)

    Martínez, L. J.; Pelini, T.; Waselowski, V.; Maze, J. R.; Gil, B.; Cassabois, G.; Jacques, V.

    2016-09-01

    Among a variety of layered materials used as building blocks in van der Waals heterostructures, hexagonal boron nitride (hBN) appears as an ideal platform for hosting optically active defects owing to its large band gap (˜6 eV ). Here we study the optical response of a high-purity hBN crystal under green laser illumination. By means of photon correlation measurements, we identify individual defects emitting a highly photostable fluorescence under ambient conditions. A detailed analysis of the photophysical properties reveals a high quantum efficiency of the radiative transition, leading to a single photon source with very high brightness (˜4 ×106 counts s-1). These results illustrate how the wide range of applications offered by hBN could be further extended to photonic-based quantum information science and metrology.

  2. Nodular graphite formation in vacuum melted high purity Fe-C-Si alloys

    NASA Astrophysics Data System (ADS)

    Dhindaw, B.; Verhoeven, J. D.

    1980-06-01

    This paper describes a study of the cast structure of vacuum melted high purity Fe-C-Si alloys with emphasis on hypoeutectic and eutectic compositions. Nodular graphite was observed to form at high cooling rates and coral graphite at low cooling rates. This result was also confirmed by a limited study on directional solidification of alloys prepared from the same starting materials. The formation of nodular graphite at the high cooling rates was suppressed to near zero by changing the starting iron from 99.94 pct electrolytic iron to an ultra-pure zone refined iron, or by holding the melt at a low super-heat prior to cooling. Chemical analysis showed only that the impurity responsible for nodular formation was present at the low ppm level. An attempt is made to explain the appearance of the various microstructures in terms of the nucleation and growth of nodular graphite, coral graphite and the carbide structure of white iron.

  3. The importance of Soret transport in the production of high purity silicon for solar cells

    NASA Technical Reports Server (NTRS)

    Srivastava, R.

    1985-01-01

    Temperature-gradient-driven diffusion, or Soret transport, of silicon vapor and liquid droplets is analyzed under conditions typical of current production reactors for obtaining high purity silicon for solar cells. Contrary to the common belief that Soret transport is negligible, it is concluded that some 15-20 percent of the silicon vapor mass flux to the reactor walls is caused by the high temperature gradients that prevail inside such reactors. Moreover, since collection of silicon is also achieved via deposition of silicon droplets onto the walls, the Soret transport mechanism becomes even more crucial due to size differences between diffusing species. It is shown that for droplets in the 0.01 to 1 micron diameter range, collection by Soret transport dominates both Brownian and turbulent mechanisms.

  4. Map showing high-purity silica sand of Middle Ordovician age in the Midwestern states

    USGS Publications Warehouse

    Ketner, Keith B.

    1979-01-01

    Certain quartz sands of Middle Ordovician age in the Midwestern States are well known for their purity and are exploited for a wide variety of industrial uses. The principal Middle Ordovician formations containing high-purity sands are the St. Peter Sandstone which crops out extensively from Minnesota to Arkansas; the Everton Formation principally of Arkansas; and the Oil Creek, McLish, and Tulip Creek Formations (all of the Simpson Group) of Oklahoma. The St. Peter and sandy beds in the other formations are commonly called "sandstones," but a more appropriate term is "sands" for in most fresh exposures they are completely uncemented or very weakly cemented. On exposure to air, uncemented sands usually become "case hardened" where evaporating ground water precipitates mineral matter at the surface; but this is a surficial effect. This report summarizes the available information on the extent of exposures, range of grain size, and chemical composition of the Middle Ordovician sands.

  5. High-purity InAs1-xSbx epilayer grown by a LPE technique

    NASA Astrophysics Data System (ADS)

    Lv, Y. F.; Hu, S. H.; Xu, Y. G.; Zhou, W.; Wang, Y.; Wang, R.; Yu, G. L.; Dai, N.

    2015-04-01

    High-purity InAs1-xSbx films with x=0.06 were successfully grown on InAs (100) substrates by liquid phase epitaxy (LPE). Procedures were applied to purify InAs1-xSbx precursor material, which included prolonging baking time in hydrogen and adding rare-earth element gadolinium (Gd) to the growth melt. Electrical transport properties of InAs1-xSbx film were investigated by Hall measurements in the condition of the conductive InAs substrate being removed completely by chemical mechanical polishing (CMP) to eliminate its influence on the measurements. Hall measurement results show carrier concentration and mobility of our InAs1-xSbx samples are superior to the other reported values when a combinational purification procedure is applied.

  6. Detection of moisture content in high-purity ammonia by means of diode-laser spectroscopy

    NASA Astrophysics Data System (ADS)

    Berezin, A. G.; Nadezhdinskii, A. I.; Ponurovskii, Y. Y.; Stavrovskii, D. B.; Vyazov, I. E.; Kotkov, A. P.; Ivanov, V. A.; Grishnova, N. D.; Polezhaev, D. M.; Sidorov, V. A.; Kotkov, D. A.

    2008-02-01

    The aim of this work was the development of an as-simple-as-possible instrument for trace moisture concentration measurements in high-purity ammonia. A near-infrared diode-laser-based instrument has been applied to measure the humidity in a process of on-line detection of water in ammonia during industrial purification. The results of water concentration measurements were compared with alternative techniques (primarily dew-point detection) and good agreement was achieved. The long-term sensitivity of such a diode-laser-based instrument was estimated to be 5 ppm. The calculation of the water concentration from measurements of the integrated volume of water contained in the heavy fraction, extracted during the purification process, yields an even lower detection limit of less than 0.1 ppm, depending on the initial ammonia purity.

  7. Statistics of high purity nickel microstructure from high energy x-ray diffraction microscopy.

    SciTech Connect

    Hefferan, C. M.; Li, S. F.; Lind, J. F.; Lienert, U.; Rollett, A. D.; Winblatt, P.; Suter, R. M.; X-Ray Science Division; Univ. of Pittsburgh; Carnegie Mellon Univ.

    2009-01-01

    We have measured and reconstructed via forward modeling a small volume of microstructure of high purity, well annealed nickel using high energy xray diffraction microscopy (HEDM). Statistical distributions characterizing grain orientations, intra-granular misorientations, and nearest neighbor grain misorientations are extracted. Results are consistent with recent electron backscatter diffraction measurements. Peaks in the grain neighbor misorientation angle distribution at 60 degrees (S3) and 39 degrees (S9) have resolution limited widths of {approx}0:14 degree FWHM. The analysis demonstrates that HEDM can recover grain and grain boundary statistics comparable to OIM volume measurements; more extensive data sets will lead to full, five parameter grain boundary character distributions. Due to its non-destructive nature, HEDM can then watch, both statistically and through tracking of individual grains and boundaries, the evolution of such distributions with processing of the sample.

  8. High Strain-Rate Response of High Purity Aluminum at Temperatures Approaching Melt

    SciTech Connect

    Grunschel, S E; Clifton, R J; Jiao, T

    2010-01-28

    High-temperature, pressure-shear plate impact experiments were conducted to investigate the rate-controlling mechanisms of the plastic response of high-purity aluminum at high strain rates (10{sup 6} s{sup -1}) and at temperatures approaching melt. Since the melting temperature of aluminum is pressure dependent, and a typical pressure-shear plate impact experiment subjects the sample to large pressures (2 GPa-7 GPa), a pressure-release type experiment was used to reduce the pressure in order to measure the shearing resistance at temperatures up to 95% of the current melting temperature. The measured shearing resistance was remarkably large (50 MPa at a shear strain of 2.5) for temperatures this near melt. Numerical simulations conducted using a version of the Nemat-Nasser/Isaacs constitutive equation, modified to model the mechanism of geometric softening, appear to capture adequately the hardening/softening behavior observed experimentally.

  9. Role of deformation twins in static recrystallization kinetics of high-purity alpha titanium

    NASA Astrophysics Data System (ADS)

    Won, Jong Woo; Lee, Taekyung; Hong, Seong-Gu; Lee, Yongmoon; Lee, Jeong Hun; Lee, Chong Soo

    2016-11-01

    The importance of deformation twins in static recrystallization kinetics of high-purity alpha titanium was investigated by carrying out thermal annealing tests of deformed materials in combination with electron-backscatterdiffraction- based microstructural analysis. Prior to thermal annealing, the material was compressed to a true strain of 0.22 along three directions to introduce different twinning characteristics. Our results showed that deformation twins substantially promoted the static recrystallization process by deepening the microstructural inhomogeneity induced by the formation of twin boundaries and twinning-induced crystallographic lattice reorientation. Twin morphology was also observed to be important because it influenced the extent of microstructural inhomogeneity. Intersecting twin morphology, caused by the activation of multiple twin variants, was more effective than parallel twin morphology, caused by the activation of a single twin variant (or a twin variant pair), because it gave rise to more twin boundaries, more twin boundary junctions (intersections, triple junctions, etc.), and greater in-grain crystallographic orientation spread.

  10. A Rapid and Cost-Effective Laser Based Synthesis of High Purity Cadmium Selenide Quantum Dots.

    PubMed

    Gondall, M A; Qahtan, Talal F; Dastageer, M A; Yamani, Z H; Anjum, D H

    2016-01-01

    A rapid and cost effective method is developed to synthesize high purity cadmium Selenide (CdSe) quantum dots in acetone medium using second harmonic of Nd:YAG nanosecond pulsed laser of 532 nm wavelength. The thermal agglomeration due the nanosecond pulse duration of the laser was successfully eliminated by using unfocussed laser beam and thereby providing a favorable conditions for the synthesis of quantum dots having the grain size of 3 nm. The morphological and optical characterizations like XRD, HRTEM, optical absorption of the synthesized CdSe quantum dots, reveal that the material possesses the similar characteristics of the one synthesized through cumbersome wet chemical methods. Relative to the CdSe bulk material, the synthesized CdSe quantum dots showed a blue shift in the measured band gap energy from near infrared spectral region to visible region, making this material very attractive for many solar energy harvesting applications like photo-catalysis and solar cells.

  11. Hot working of high purity Fe-C alloys in the α-range

    NASA Astrophysics Data System (ADS)

    Montheillet, F.; Le Coze, J.

    2010-07-01

    The influence of carbon in solid solution on the stress-strain curves of α-iron was investigated using model alloys prepared from high purity iron. Uniaxial compression tests were carried out within the ferritic domain at temperatures between 700 and 880 °C. Oscillating stress-strain curves observed at high temperatures and low strain rates indicate that discontinuous dynamic recrystallization takes place. The macroscopic strain rate sensitivities m and apparent activation energies Q associated with the flow stress are not significantly modified by carbon additions. By contrast, the "mesoscopic" parameters h and r associated with strain hardening and dynamic recovery, respectively, are strongly dependent on the carbon content. Finally, an estimation of the grain boundary mobilities during dynamic recrystallization was carried out from the above rheological data.

  12. Defects interaction processes in deformed high purity polycrystalline molybdenum at elevated temperatures

    NASA Astrophysics Data System (ADS)

    Lambri, O. A.; Bonifacich, F. G.; Bozzano, P. B.; Zelada, G. I.; Plazaola, F.; García, J. A.

    2014-10-01

    Mechanical spectroscopy (damping and elastic modulus as a function of temperature) and transmission electron microscopy studies have been performed in high purity polycrystalline molybdenum plastically deformed to different values of tensile and torsion strain. Mechanical spectroscopy measurements were performed from room temperature up to 1285 K. A relaxation peak in polycrystalline molybdenum related to the movement of dislocations into lower energy configurations near grain boundaries has been discovered to appear around 1170 K. The activation energy of the peak is 4.2 eV ± 0.5 eV. This relaxation phenomenon involves the interaction between vacancies and mobile dislocations near the grain boundaries. It should be highlighted that this relaxation process is controlled by the arrangement of vacancies and dislocations which occur at temperature below 1070 K.

  13. Scalable fabrication of high purity diamond nanocrystals with long-spin-coherence nitrogen vacancy centers.

    PubMed

    Trusheim, Matthew E; Li, Luozhou; Laraoui, Abdelghani; Chen, Edward H; Bakhru, Hassaram; Schröder, Tim; Gaathon, Ophir; Meriles, Carlos A; Englund, Dirk

    2014-01-08

    The combination of long spin coherence time and nanoscale size has made nitrogen vacancy (NV) centers in nanodiamonds the subject of much interest for quantum information and sensing applications. However, currently available high-pressure high-temperature (HPHT) nanodiamonds have a high concentration of paramagnetic impurities that limit their spin coherence time to the order of microseconds, less than 1% of that observed in bulk diamond. In this work, we use a porous metal mask and a reactive ion etching process to fabricate nanocrystals from high-purity chemical vapor deposition (CVD) diamond. We show that NV centers in these CVD nanodiamonds exhibit record-long spin coherence times in excess of 200 μs, enabling magnetic field sensitivities of 290 nT Hz(-1/2) with the spatial resolution characteristic of a 50 nm diameter probe.

  14. Experimental research of phase transition's kinetics in a liquid melt of high-purity aluminum

    NASA Astrophysics Data System (ADS)

    Vorontsov, V. B.; Zhuravlev, D. V.; Cherepanov, A. S.

    2015-08-01

    This scientific work is devoted to the studying of the genetic connection structures of solid and liquid phases. Fourier analysis of signals of acoustic emission (AE) accompanying melting high purity aluminum from the melting point up to t = 860°C was performed. Based on the results of previous studies cluster formations in the melt - the micro-regions, those retain crystallinity (areas with short-range order of symmetry) were considered as the source of AE. The experimental data allowed to follow the dynamics of disorder zones range order in the melt with increasing melt temperature up to their complete destruction. The presented results of spectral analysis of the signals were analyzed from the standpoint of the theory of cluster melting metals.

  15. Re-examination of creep behaviour of high purity aluminium at low temperature

    NASA Astrophysics Data System (ADS)

    Ueda, S.; Kameyama, T.; Matsunaga, T.; Kitazono, K.; Sato, E.

    2010-07-01

    The deformation behaviour of high-purity aluminium at low temperatures was investigated in order to re-examine Ashby-type deformation mechanism map. All specimens with different purities showed significant creep below room temperature. Under the same stress and temperature, the steady-state creep rate increased with increasing purity of the material. They showed stress exponents around 5.0 and apparent activation energies around 20 kJ/mol at temperatures below about 400 K, and 4.0 and 70-80 kJ/mol at temperatures above that temperature. The grain size had no effect in the low temperature region. From the microstructural observation, secondary slip system was observed. These features imply that pure aluminium deforms in the different mode from the ambient temperature creep of h.c.p. metals which has similar activation energy.

  16. URANIUM RECOVERY AND PURIFICATION PROCESS AND PRODUCTION OF HIGH PURITY URANIUM TETRAFLUORIDE

    DOEpatents

    Bailes, R.H.; Long, R.S.; Grinstead, R.R.

    1957-09-17

    A process is described wherein an anionic exchange technique is employed to separate uramium from a large variety of impurities. Very efficient and economical purification of contamimated uranium can be achieved by treatment of the contaminated uranium to produce a solution containing a high concentration of chloride. Under these conditions the uranium exists as an aniomic chloride complex. Then the uranium chloride complex is adsorbed from the solution on an aniomic exchange resin, whereby a portion of the impurities remain in the solution and others are retained with the uramium by the resin. The adsorbed impurities are then removed by washing the resin with pure concentrated hydrochloric acid, after which operation the uranium is eluted with pure water yielding an acidic uranyl chloride solution of high purity.

  17. The relationship between induction time for pitting and pitting potential for high purity aluminum.

    SciTech Connect

    Wall, Frederick Douglas; Vandenavyle, Justin J.; Martinez, Michael A.

    2003-08-01

    The objective of this study was to determine if a distribution of pit induction times (from potentiostatic experiments) could be used to predict a distribution of pitting potentials (from potentiodynamic experiments) for high-purity aluminum. Pit induction times were measured for 99.99 Al in 50 mM NaCl at potentials of -0.35, -0.3, -0.25, and -0.2 V vs. saturated calomel electrode. Analysis of the data showed that the pit germination rate generally was an exponential function of the applied potential; however, a subset of the germination rate data appeared to be mostly potential insensitive. The germination rate behavior was used as an input into a mathematical relationship that provided a prediction of pitting potential distribution. Good general agreement was found between the predicted distribution and an experimentally determined pitting potential distribution, suggesting that the relationships presented here provide a suitable means for quantitatively describing pit germination rate.

  18. Preparation and characterization of (10)B boric acid with high purity for nuclear industry.

    PubMed

    Zhang, Weijiang; Liu, Tianyu; Xu, Jiao

    2016-01-01

    Boric acid is often added into coolant as neutron capture agent for pressurized water reactor, whose amount is influenced by its abundance and purity. Therefore, the preparation of enriched (10)B boric acid with high purity is beneficial to nuclear industry. (10)B is also used in developing tumor-specific boronated drugs in boron neutron capture therapy. The boronated drug can be administered to patient intravenously, intratumorally, or deposited at tumor site in surgical excision. Thus, enriched (10)B boric acid is of practical significance in the field of medicine. Self-made boron trifluoride-methanol-complex solution was selected as one of the experimental reagents, and the preparation of (10)B acid was realized by one-step reaction for the complexes with water and calcium chloride. The determination of electrical conductivity in reaction process proves that the optimum reaction time was 16-20 h. Furthermore, the effect of reaction time, ratio of calcium chloride to complex as well as the amount of water on the purity and yield of boric acid was investigated. Finally, the optimum reaction time was 20 h, the optimal solid-liquid ratio (molar ratio) was 3:1, and the amount of water was 1 L of deionized water for each mol of the complex. H2O2 was added in the reaction process to remove Fe(2+). After recrystallization, IR spectra of (10)B boric acid was measured and compared with standard to verify the product of boric acid. The feasibility of the preparation method was determined by the detection of XRD of boric acid. To observe the morphology by polarizing microscope, crystal structure was obtained. The purity of the final product is 99.95 %, and the yield is 96.47 %. The ion concentration of boric acid accords with the national standard of high purity, which was determined by ICP.

  19. Recycling of high purity selenium from CIGS solar cell waste materials

    SciTech Connect

    Gustafsson, Anna M.K. Foreman, Mark R.StJ.; Ekberg, Christian

    2014-10-15

    Highlights: • A new method for recycling of selenium from CIGS solar cell materials is presented. • Separation of selenium as selenium dioxide after heating in oxygen atmosphere. • Complete selenium separation after oxidation of <63 μm particles at 800 °C for 1 h. • After reduction of selenium dioxide the selenium purity was higher than 99.999 wt%. - Abstract: Copper indium gallium diselenide (CIGS) is a promising material in thin film solar cell production. To make CIGS solar cells more competitive, both economically and environmentally, in comparison to other energy sources, methods for recycling are needed. In addition to the generally high price of the material, significant amounts of the metals are lost in the manufacturing process. The feasibility of recycling selenium from CIGS through oxidation at elevated temperatures was therefore examined. During oxidation gaseous selenium dioxide was formed and could be separated from the other elements, which remained in solid state. Upon cooling, the selenium dioxide sublimes and can be collected as crystals. After oxidation for 1 h at 800 °C all of the selenium was separated from the CIGS material. Two different reduction methods for reduction of the selenium dioxide to selenium were tested. In the first reduction method an organic molecule was used as the reducing agent in a Riley reaction. In the second reduction method sulphur dioxide gas was used. Both methods resulted in high purity selenium. This proves that the studied selenium separation method could be the first step in a recycling process aimed at the complete separation and recovery of high purity elements from CIGS.

  20. High purity polyimide analysis by solid sampling graphite furnace atomic absorption spectrometry

    NASA Astrophysics Data System (ADS)

    Santos, Rafael F.; Carvalho, Gabriel S.; Duarte, Fabio A.; Bolzan, Rodrigo C.; Flores, Erico M. M.

    2017-03-01

    In this work, Cr, Cu, Mn, Na and Ni were determined in high purity polyimides (99.5%) by solid sampling graphite furnace atomic absorption spectrometry (SS-GFAAS) using Zeeman effect background correction system with variable magnetic field, making possible the simultaneous measurement at high or low sensitivity. The following analytical parameters were evaluated: pyrolysis and atomization temperatures, feasibility of calibration with aqueous solution, linear calibration range, sample mass range and the use of chemical modifier. Calibration with aqueous standard solutions was feasible for all analytes. No under or overestimated results were observed and up to 10 mg sample could be introduced on the platform for the determination of Cr, Cu, Mn, Na and Ni. The relative standard deviation ranged from 3 to 20%. The limits of detection (LODs) achieved using the high sensitivity mode were as low as 7.0, 2.5, 1.7, 17 and 0.12 ng g- 1 for Cr, Cu, Mn, Na and Ni, respectively. No addition of chemical modifier was necessary, except for Mn determination where Pd was required. The accuracy was evaluated by analyte spike and by comparison of the results with those obtained by inductively coupled plasma optical emission spectrometry and inductively coupled plasma mass spectrometry after microwave-assisted digestion in a single reaction chamber system and also by neutron activation analysis. No difference among the results obtained by SS-GFAAS and those obtained by alternative analytical methods using independent techniques. SS-GFAAS method showed some advantages, such as the determination of metallic contaminants in high purity polyimides with practically no sample preparation, very low LODs, calibration with aqueous standards and determination in a wide range of concentration.

  1. Sequence-specific sup 1 H NMR assignments, secondary structure, and location of the calcium binding site in the first epidermal growth factor like domain of blood coagulation factor IX

    SciTech Connect

    Huang, L.H.; Cheng, H.; Sweeney, W.V. ); Pardi, A. ); Tam, J.P. )

    1991-07-30

    Factor IX is a blood clotting protein that contains three regions, including a {gamma}-carboxyglutamic acid (Gla) domain, two tandemly connected epidermal growth factor like (EGF-like) domains, and a serine protease region. The protein exhibits a high-affinity calcium binding site in the first EGF0like domain, in addition to calcium binding in the Gla domain. The first EGF-like domain, factor IX (45-87), has been synthesized. Sequence-specific resonance assignment of the peptide has been made by using 2D NMR techniques, and its secondary structure has been determined. The protein is found to have two antiparallel {beta}-sheets, and preliminary distance geometry calculations indicate that the protein has two domains, separated by Trp{sup 28}, with the overall structure being similar to that of EGF. An NMR investigation of the calcium-bound first EGF-like domain indicates the presence and location of a calcium binding site involving residues on both strands of one of the {beta}-sheets as well as the N-terminal region of the peptide. These results suggest that calcium binding in the first EGF-like domain could induce long-range (possibly interdomain) conformational changes in factor IX, rather than causing structural alterations in the EGF-like domain itself.

  2. Influence of strain rate and temperature on the structure/property behavior of high-purity titanium

    SciTech Connect

    Gray, G.T. III

    1997-05-01

    The effect of strain rate, temperature, grain size, and texture on the substructure and mechanical response of high-purity polycrystalline titanium is presented. The compressive stress-strain response of 20 and 240 {mu}m grain size high-purity Ti was found to depend on both the applied strain rate; 0.001 {le} {epsilon} {le} 7500 s{sup -1}, and the test temperature; 77 {le} T {le} 873 K. The rate of strain hardening in Ti is seen to increase with increasing strain rate. The substructure of high-purity Ti deformed at high-strain-rate or quasi-statically at 77K displayed a higher incidence of deformation twinning than during quasi-static deformation at 298K.

  3. Preparation & characterization of high purity Cu2 ZnSn(SxSe1-x)4 nanoparticles

    NASA Astrophysics Data System (ADS)

    Negash, Bethlehem G.

    Research in thin film solar cells applies novel techniques to synthesize cost effective and highly efficient absorber materials in order to generate electricity directly from solar energy. Of these materials, copper zinc tin sulfoselenide (Cu2ZnSn(SxSe1-x) 4) nanoparticles have shown great promise in solar cell applications due to optimal material properties as well as low cost & relative abundance of materials.1,2 Sulfoselenide nanoparticles have also a broader impact in other industries including electronics3, LED 4, and biomedical research5. Of the many routes of manufacturing these class of semiconductors, colloidal synthesis of Cu 2ZnSn(SxSe1-x)4 offers a scalable, low cost and high-throughput route for manufacturing high efficiency thin-film solar cells. Hydrazine processed Cu2ZnSn(SxSe1-x )4 devices have reached a record power conversion efficiency (PCE) of 12.6%, much higher than the 9.6% reported for physical vapor deposition (PVD) systems.6,7. Despite high efficiencies, wet synthesis of nanoparticles, however, is made more complicated in multi-element, quaternary and quinary systems such as copper zinc tin sulfoselenide (CZTSSe) and copper indium gallium diselenide (CIGSe). One major disadvantage in these systems is growth of the desired quaternary or quinary phase in competition with unwanted binary and ternary phases with low energy of formation.8,9 Moreover, various reaction parameters such as reaction time, temperature, and choice of ligand also affect, chemical as well as physical properties of resulting nanoparticles. Understanding of the formation mechanisms of the particles is necessary in order to address some of these challenges in wet synthesis of CZTSSe nanoparticles. In this study, we investigate synthesis conditions & reaction parameters which yield high purity Cu2ZnSn(SxSe1-x) 4 nanoparticles as well as attempt to understand the growth mechanism of these nanoparticles. This was achieved by manipulating anion precursor preparation routes as

  4. Platelet Glycoprotein Ib-IX and Malignancy

    DTIC Science & Technology

    2010-09-01

    cancer to metastatic disease . During the next year we propose to examine the relevance of platelet receptors in models of spontaneous metastasis. A...the prognosis for recovery from breast cancer cannot be under emphasized. Indeed, the spread of metastatic disease represents a fundamental change in...IX have been identified, including von Willebrand factor (vWF) and thrombin, illustrating platelet GP Ib-IX as a major initiator of platelet thrombus

  5. The rates of G:C-->T:A and G:C-->C:G transversions at CpG dinucleotides in the human factor IX gene.

    PubMed

    Ketterling, R P; Vielhaber, E; Sommer, S S

    1994-05-01

    We have identified eight independent transversions at CpG in 290 consecutive families with hemophilia B. These eight transversions account for 16.3% of all independent transversions in our sample, yet the expected frequency of CpG transversions at random in the factor IX gene is only 2.6% (P < .01). The aggregate data suggest that the two types of CpG transversions (G:C-->T:A and G:C-->C:G) possess similar mutation rates (24.8 x 10(-10) and 20.6 x 10(-10), respectively), which are about fivefold greater than the comparable rates for transversions at non-CpG dinucleotides. The enhancement of transversions at CpG suggests that the model by which mutations occur at CpG may need to be reevaluated. The relationship, if any, between deamination of 5-methyl cytosine and enhancement of transversions at CpG remains to be defined.

  6. Multidimensional Study on Spall Behavior of High-Purity Copper Under Sliding Detonation

    NASA Astrophysics Data System (ADS)

    Yang, Yang; Peng, Zhiqiang; Guo, Zhaoliang; Luo, Shuhong; Tang, Tiegang; Hu, Haibo; Zhang, Qingming

    2015-09-01

    The spall behaviors of high-purity copper samples with different heat treatment histories were investigated using optical microscopy and X-ray computer tomography (XRCT). The spall samples were obtained by sliding detonation experiments at low pressures (2 to 4 GPa). It was found that the spall planes created by sliding detonation in this experiment are similar to the spall planes created by plate impact test, except for more secondary damage residual around the main spall plane. The results of damage degree, the shape, and the distributions of voids obtained by the means of metallography (2D) and XRCT (3D) statistics were consistent. For similar microstructure, the maximum damage degree and damage zone width increase with increasing shock stress. Whereas the ranges of voids distribution parallel to the shock stress direction decreases with the increasing of shock stress. For the shock stress is similar, the shape of voids in annealed samples are closed to spheres, their mean flatness is 0.51. The voids in samples with thermo-mechanical treatment histories are sheet like with mean flatness 0.16. The difference in grain size (40 and 9 μm) may be the main reason of such difference.

  7. Microstructure and helium irradiation performance of high purity tungsten processed by cold rolling

    NASA Astrophysics Data System (ADS)

    Chen, Zhe; Han, Wenjia; Yu, Jiangang; Kecskes, Laszlo; Zhu, Kaigui; Wei, Qiuming

    2016-10-01

    This work aims to investigate the effects of confined cold rolling on the evolution of microstructure, hardness, and helium irradiation performance of high purity tungsten (W). Using a final rolling temperature of 450 °C, W samples were severely deformed by confined cold rolling up to equivalent strains (εeq) of 1.6 and 3.3. Experimental results indicate that the average grain size of W specimens processed by confined cold rolling has been greatly reduced, and the rolled W samples with εeq ∼3.3 do not show an "ideal texture" of (001)[110] which is the expected texture of bcc metals processed by conventional cold rolling. The irradiation resistance against 60 keV He+ ions with up to a dose of 1.5 × 1022 ions·m-2 of the rolled W is compared to that of the as-received W. Results show that, due to an improvement of the metal's ductility, blister bursting with a partially opened lid forms on the surface of the rolled W, whereas blister bursting with a fully opened lid forms on the surface of the as-received W.

  8. Determination of halogens and sulfur in high-purity polyimide by IC after digestion by MIC.

    PubMed

    Krzyzaniak, Sindy R; Santos, Rafael F; Dalla Nora, Flavia M; Cruz, Sandra M; Flores, Erico M M; Mello, Paola A

    2016-09-01

    In this work, a method for sample preparation of high-purity polyimide was proposed for halogens and sulfur determination by ion chromatography (IC) with conductivity detection and, alternatively, by inductively coupled plasma mass spectrometry (ICP-MS). A relatively high polyimide mass (600mg) was completely digested by microwave-induced combustion (MIC) using 20bar of O2 and 50mmolL(-1) NH4OH as absorbing solution. These conditions allowed final solutions with low carbon content (<10mgL(-1)) and suitable pH for analysis by both IC and ICP-MS. The accuracy was evaluated using a certified reference material of polymer for Cl, Br and S and spike recovery experiments for all analytes. No statistical difference (t-test, 95% of confidence level) was observed between the results obtained for Cl, Br and S by IC after MIC and the certified values. In addition, spike recoveries obtained for F, Cl, Br, I and S ranged from 94% to 101%. The proposed method was suitable for polyimide decomposition for further determination of halogens and sulfur by IC and by ICP-MS (Br and I only). Taking into account the lack of methods and the difficulty of bringing this material into solution, MIC can be considered as a suitable alternative for the decomposition of polyimide for routine quality control of halogens and sulfur using IC or ICP-MS.

  9. Influence of Ta content in high purity niobium on cavity performance: preliminary results

    SciTech Connect

    Carneiro, Tadeu; Klinkenberg, Christian; Kneisel, Peter; Myneni, Ganapati; Singer, Waldemar; Singer, Xenia; Proch, Dieter

    2004-08-01

    In a previous paper [1] a program for reducing the costs of high purity niobium was outlined. This program was based on the fact that niobium prices could be reduced, if a higher content of Ta, which does not significantly affect the RRR-value, could be tolerated for high performance cavities. This contribution reports on the execution of this program and its present status. Four ingots with different Ta contents have been melted and transformed into sheets. In each manufacturing step material quality has been monitored, using chemical analysis, thermal conductivity measurements and evaluation of mechanical properties. The niobium sheets have been scanned for defects by an eddy current device. Two single cell cavities (CEBAF geometry) have been fabricated from each of three ingots, with Ta concentrations of 150, 600 and 1300 wtppm. A series of tests have been performed on each cavity with increasing amount of material removal. This contribution reports on the test results and gives an analysis of the data.

  10. Microwave photoconductivity decay characterization of high-purity 4H-SiC substrates

    NASA Astrophysics Data System (ADS)

    Kumar, R. J.; Borrego, J. M.; Gutmann, R. J.; Jenny, J. R.; Malta, D. P.; Hobgood, H. McD.; Carter, C. H.

    2007-07-01

    A microwave photoconductivity decay (MPCD) technique, which probes conductivity change in wafers in response to either an above-band-gap or below-band-gap laser pulse, has been used to characterize recombination lifetime in high-purity 4H-SiC substrates produced with three different anneal processes. The above-band-gap (266nm) decay times vary from ˜10ns to tens of microseconds in the 4H-SiC substrates depending on the wafer growth parameters. Wafers produced using the three processes A (as-grown), B (annealed at 2000°C), and C (annealed at 2600°C) have decay times of 10-20ns, 50-500ns, and tens of microseconds, respectively. The differences in decay times are attributed to low, medium, and high densities of recombination centers in process C, B, and A wafers, respectively. The MPCD results correlate with other characterization results such as deep level transient spectroscopy, which also showed that the 2600°C anneal process significantly reduces defect densities, resulting in the enhanced recombination lifetimes. Modeling and one-dimensional simulations indicate a trapping center closer to the conduction band results in a longer MPCD decay transient, but such a trapping based model for the enhanced lifetimes is not compatible with the wide range of experimental characterization results described in this work, which indicate an annealing out of recombination centers at 2600°C.

  11. Influence of Ta content in high purity niobium on cavity performance

    SciTech Connect

    P. Kneisel; G. Ciovati; G. R. Myneni; W. Singer; X. Singer; D. Proch; T. Carneiro

    2005-05-01

    In a previous paper [1] we have reported about initial tests of single cell 1500 MHz cavities made from high purity niobium with three different Ta contents of 160 ppm , {approx}600 ppm and {approx}1400 ppm. These cavities had been treated by buffered chemical polishing several times and 100 {micro}m, 200 {micro}m and 300 {micro}m of material had been removed from the surfaces. This contribution reports about subsequent tests following post purification heat treatments with Ti and ''in situ'' baking. As a result, all cavities exhibited increased quench fields due to the improved thermal conductivity after the heat treatment. After the ''in situ'' baking at 120 C for {approx} 40 hrs the always present Q-drop at high fields disappeared and further improvements in accelerating gradient could be realized. Gradients as high as E{sub acc} = 35 MV/m were achieved and there were no clear indications that the cavity performance was influenced by the Ta content in the material. A multi-cell cavity from the high Ta content material has been fabricated and initial results are reported.

  12. Determination of nitrogen monoxide in high purity nitrogen gas with an atmospheric pressure ionization mass spectrometer

    NASA Technical Reports Server (NTRS)

    Kato, K.

    1985-01-01

    An atmospheric pressure ionization mass spectrometric (API-MS) method was studied for the determination of residual NO in high purity N2 gas. The API-MS is very sensitive to NO, but the presence of O2 interferes with the NO measurement. Nitrogen gas in cylinders as sample gas was mixed with NO standard gas and/or O2 standard gas, and then introduced into the API-MS. The calibration curves of NO and O2 has linearity in the region of 0 - 2 ppm, but the slopes changed with every cylinder. The effect of O2 on NO+ peak was additive and proportional to O2 concentration in the range of 0 - 0.5 ppm. The increase in NO+ intensity due to O2 was (0.07 - 0.13)%/O2, 1 ppm. Determination of NO and O2 was carried out by the standard addition method to eliminate the influence of variation of slopes. The interference due to O2 was estimated from the product of the O2 concentration and the ratio of slope A to Slope B. Slope A is the change in the NO+ intensity with the O2 concentration. Slope B is the intensity with O2 concentration.

  13. Preparation of the high purity gingerols from ginger by dummy molecularly imprinted polymers.

    PubMed

    Ji, Wenhua; Ma, Xiuli; Zhang, Jinghua; Xie, Hongkai; Liu, Feng; Wang, Xiao

    2015-03-27

    In this work, a dummy molecularly imprinted polymers (MIPs) were developed as the selective sorbents for preparation of the high purity gingerols from ginger for the first time. The dummy template molecule with similar structural skeleton to gingerols, N-vanillylnonanamide, has been designed and synthesized. The performance of the MIPs and non-imprinted polymers (NIPs) were evaluated including selective recognition capacity, adsorption isotherm, and adsorption kinetics. Optimization of various parameters affecting dummy molecular imprinted solid phase extraction (MISPE), such as the type and flow rate of the loading solvent, the composition and volume of the eluting solvent, and the composition and volume of the washing solvent were investigated. Gingerols with the percent recovery of 80 and the percent purity of 99.1 were obtained from the extracts of ginger by MISPE. Besides, gingerols obtained by MISPE had more powerful activity of eliminating free radical compared with extracts before extraction with the MISPE column. Application of MIPs with a high affinity toward three gingerols provides a novel method for obtaining a group of compounds which have likely active groups from natural products.

  14. Simulation study comparing high-purity germanium and cadmium zinc telluride detectors for breast imaging

    NASA Astrophysics Data System (ADS)

    Campbell, D. L.; Peterson, T. E.

    2014-11-01

    We conducted simulations to compare the potential imaging performance for breast cancer detection with High-Purity Germanium (HPGe) and Cadmium Zinc Telluride (CZT) systems with 1% and 3.8% energy resolution at 140 keV, respectively. Using the Monte Carlo N-Particle (MCNP5) simulation package, we modelled both 5 mm-thick CZT and 10 mm-thick HPGe detectors with the same parallel-hole collimator for the imaging of a breast/torso phantom. Simulated energy spectra were generated, and planar images were created for various energy windows around the 140 keV photopeak. Relative sensitivity and scatter and the torso fractions were calculated along with tumour contrast and signal-to-noise ratios (SNR). Simulations showed that utilizing a ±1.25% energy window with an HPGe system better suppressed torso background and small-angle scattered photons than a comparable CZT system using a -5%/+10% energy window. Both systems provided statistically similar contrast and SNR, with HPGe providing higher relative sensitivity. Lowering the counts of HPGe images to match CZT count density still yielded equivalent contrast between HPGe and CZT. Thus, an HPGe system may provide equivalent breast imaging capability at lower injected radioactivity levels when acquiring for equal imaging time.

  15. In vivo recovery with products of very high purity--assay discrepancies.

    PubMed

    Lusher, J M; Hillman-Wiseman, C; Hurst, D

    1998-07-01

    In view of reports of FVIII assay discrepancies in post-infusion plasma samples depending on methods used, we compared FVIII results run by each of four different methods following infusion of rFVIII (Kogenate). Nine persons with haemophilia A were infused with each of two lots of product. Plasma samples were obtained at baseline, and at 10 min, 30 min, 1, 2, 4, 8, 12, 14, 30 and 48 h post-infusion for measurement of FVIII. FVIII assay methods were chromogenic, and one-stage APTT using three different types of activators: micronized, silica, ellagic acid, and kaolin. The same reference plasma standard was used throughout. Results demonstrated a consistent difference in FVIII values, with chromogenic assays being considerably higher than those run by one-stage assays. The discrepancy was greatest when kaolin was the activator. These results point out the problems in attempting to determine the "correct" FVIII level in patient plasma samples following infusion of high purity FVIII preparations. Potential "pitfalls" include the standard used for defining product potency, the methods, reagents, instrumentation and standards used in assaying plasma samples and, in some instances, the characteristics of the product itself. This situation has considerable cost implications, potential impact on patient care, and makes it difficult to compare results between laboratories.

  16. Evaluation of Electric Load Following Capability on Fuel Cell System Fueled by High-Purity Hydrogen

    NASA Astrophysics Data System (ADS)

    Doi, Yusuke; Park, Deaheum; Ishida, Masayoshi; Fujisawa, Akitoshi; Miura, Shinichi

    This paper describes the electrical response in load change concerning a fuel cell system fueled by high-purity hydrogen. The purpose of this study is that the fuel cell system is applied to make up for unstable electrical output of a photovoltaic system as a renewable energy. As an alternative method of secondary battery, the fuel cell system, which is able to continuously generate power as long as fuel is supplied, is expected to provide power with high reliability and stability. To evaluate the load-following capability of a polymer electrolyte fuel cell (PEFC) system, an experimental equipment was constructed with a 200W PEFC stack (number of cells: 20, cell area: 200cm2) which was supplied with hydrogen from a compressed hydrogen cylinder and a metal hydride canister. We measured the transient phenomenon of current and cell voltage when the PEFC stack was inputted step-up current loads that changed in the range of 0∼300mA/cm2. As a result, we have found that the PEFC system with both hydrogen supply sources is able to response at a time constant of 6.6∼11.6μsec under enough oxygen supply and a load below the PEFC rated power.

  17. Simulation study comparing high-purity germanium and cadmium zinc telluride detectors for breast imaging.

    PubMed

    Campbell, D L; Peterson, T E

    2014-11-21

    We conducted simulations to compare the potential imaging performance for breast cancer detection with High-Purity Germanium (HPGe) and Cadmium Zinc Telluride (CZT) systems with 1% and 3.8% energy resolution at 140 keV, respectively. Using the Monte Carlo N-Particle (MCNP5) simulation package, we modelled both 5 mm-thick CZT and 10 mm-thick HPGe detectors with the same parallel-hole collimator for the imaging of a breast/torso phantom. Simulated energy spectra were generated, and planar images were created for various energy windows around the 140 keV photopeak. Relative sensitivity and scatter and the torso fractions were calculated along with tumour contrast and signal-to-noise ratios (SNR). Simulations showed that utilizing a ±1.25% energy window with an HPGe system better suppressed torso background and small-angle scattered photons than a comparable CZT system using a -5%/+10% energy window. Both systems provided statistically similar contrast and SNR, with HPGe providing higher relative sensitivity. Lowering the counts of HPGe images to match CZT count density still yielded equivalent contrast between HPGe and CZT. Thus, an HPGe system may provide equivalent breast imaging capability at lower injected radioactivity levels when acquiring for equal imaging time.

  18. Compensation mechanism in high purity semi-insulating 4H-SiC

    NASA Astrophysics Data System (ADS)

    Mitchel, W. C.; Mitchell, William D.; Smith, H. E.; Landis, G.; Smith, S. R.; Glaser, E. R.

    2007-03-01

    A study of deep levels in high purity semi-insulating 4H-SiC has been made using temperature dependent Hall effect (TDH), thermal and optical admittance spectroscopies, and secondary ion mass spectrometry (SIMS). Thermal activation energies from TDH varied from a low of 0.55eV to a high of 1.65eV. All samples studied showed n-type conduction with the Fermi level in the upper half of the band gap. Fits of the TDH data to different charge balance equations and comparison of the fitting results with SIMS measurements indicated that the deep levels are acceptorlike even though they are in the upper half of the band gap. Carrier concentration measurements indicated that the deep levels are present in concentrations in the low 1015cm-3 range, while SIMS results demonstrate nitrogen and boron concentrations in the low to mid-1015-cm-3 range. The results suggest that compensation in this material is a complex process involving multiple deep levels.

  19. Optimization of extraction of high purity all-trans-lycopene from tomato pulp waste.

    PubMed

    Poojary, Mahesha M; Passamonti, Paolo

    2015-12-01

    The aim of this work was to optimize the extraction of pure all-trans-lycopene from the pulp fractions of tomato processing waste. A full factorial design (FFD) consisting of four independent variables including extraction temperature (30-50 °C), time (1-60 min), percentage of acetone in n-hexane (25-75%, v/v) and solvent volume (10-30 ml) was used to investigate the effects of process variables on the extraction. The absolute amount of lycopene present in the pulp waste was found to be 0.038 mg/g. The optimal conditions for extraction were as follows: extraction temperature 20 °C, time 40 min, a solvent composition of 25% acetone in n-hexane (v/v) and solvent volume 40 ml. Under these conditions, the maximal recovery of lycopene was 94.7%. The HPLC-DAD analysis demonstrated that, lycopene was obtained in the all-trans-configuration at a very high purity grade of 98.3% while the amount of cis-isomers and other carotenoids were limited.

  20. Interaction between a high purity magnesium surface and PCL and PLA coatings during dynamic degradation.

    PubMed

    Chen, Ying; Song, Yang; Zhang, Shaoxiang; Li, Jianan; Zhao, Changli; Zhang, Xiaonong

    2011-04-01

    In this study, polycaprolactone (PCL) and polylactic acid (PLA) coatings were prepared on the surface of high purity magnesium (HPMs), respectively, and electrochemical and dynamic degradation tests were used to investigate the degradation behaviors of these polymer-coated HPMs. The experimental results indicated that two uniform and smooth polymer films with thicknesses between 15 and 20 µm were successfully prepared on the HPMs. Electrochemical tests showed that both PCL-coated and PLA-coated HPMs had higher free corrosion potentials (E(corr)) and smaller corrosion currents (I(corr)) in the modified simulated body fluid (m-SBF) at 37 °C, compared to those of the uncoated HPMs. Dynamic degradation tests simulating the flow conditions in coronary arteries were carried out on a specific test platform. The weight of the specimens and the pH over the tests were recorded to characterize the corrosion performance of those samples. The surfaces of the specimens after the dynamic degradation tests were also examined. The data implied that there was a special interaction between HPM and its polymer coatings during the dynamic degradation tests, which undermined the corrosion resistance of the coated HPMs. A model was proposed to illustrate the interaction between the polymer coatings and HPM. This study also suggested that this reciprocity may also exist on the implanted magnesium stents coated with biodegradable polymers, which is a potential obstacle for the further development of drug-eluting magnesium stents.

  1. Improving axion detection sensitivity in high purity germanium detector based experiments

    NASA Astrophysics Data System (ADS)

    Xu, Wenqin; Elliott, Steven

    2015-04-01

    Thanks to their excellent energy resolution and low energy threshold, high purity germanium (HPGe) crystals are widely used in low background experiments searching for neutrinoless double beta decay, e.g. the MAJORANA DEMONSTRATOR and the GERDA experiments, and low mass dark matter, e.g. the CDMS and the EDELWEISS experiments. A particularly interesting candidate for low mass dark matter is the axion, which arises from the Peccei-Quinn solution to the strong CP problem and has been searched for in many experiments. Due to axion-photon coupling, the postulated solar axions could coherently convert to photons via the Primakeoff effect in periodic crystal lattices, such as those found in HPGe crystals. The conversion rate depends on the angle between axions and crystal lattices, so the knowledge of HPGe crystal axis is important. In this talk, we will present our efforts to improve the HPGe experimental sensitivity to axions by considering the axis orientations in multiple HPGe crystals simultaneously. We acknowledge the support of the U.S. Department of Energy through the LANL/LDRD Program.

  2. A solvent-extraction module for cyclotron production of high-purity technetium-99m.

    PubMed

    Martini, Petra; Boschi, Alessandra; Cicoria, Gianfranco; Uccelli, Licia; Pasquali, Micòl; Duatti, Adriano; Pupillo, Gaia; Marengo, Mario; Loriggiola, Massimo; Esposito, Juan

    2016-12-01

    The design and fabrication of a fully-automated, remotely controlled module for the extraction and purification of technetium-99m (Tc-99m), produced by proton bombardment of enriched Mo-100 molybdenum metallic targets in a low-energy medical cyclotron, is here described. After dissolution of the irradiated solid target in hydrogen peroxide, Tc-99m was obtained under the chemical form of (99m)TcO4(-), in high radionuclidic and radiochemical purity, by solvent extraction with methyl ethyl ketone (MEK). The extraction process was accomplished inside a glass column-shaped vial especially designed to allow for an easy automation of the whole procedure. Recovery yields were always >90% of the loaded activity. The final pertechnetate saline solution Na(99m)TcO4, purified using the automated module here described, is within the Pharmacopoeia quality control parameters and is therefore a valid alternative to generator-produced (99m)Tc. The resulting automated module is cost-effective and easily replicable for in-house production of high-purity Tc-99m by cyclotrons.

  3. Production of Ultrafine, High-purity Ceramic Powders Using the US Bureau of Mines Developed Turbomill

    NASA Technical Reports Server (NTRS)

    Hoyer, Jesse L.

    1993-01-01

    Turbomilling, an innovative grinding technology developed by the U.S. Bureau of Mines in the early 1960's for delaminating filler-grade kaolinitic clays, has been expanded into the areas of particle size reduction, material mixing, and process reaction kinetics. The turbomill, originally called an attrition grinder, has been used for particle size reduction of many minerals, including natural and synthetic mica, pyrophyllite, talc, and marble. In recent years, an all-polymer version of the turbomill has been used to produce ultrafine, high-purity, advanced ceramic powders such as SiC, Si3N4, TiB2, and ZrO2. In addition to particle size reduction, the turbomill has been used to produce intimate mixtures of high surface area powders and whiskers. Raw materials, TiN, AlN, and Al2O3, used to produce a titanium nitride/aluminum oxynitride (TiN/AlON) composite, were mixed in the turbomill, resulting in strength increases over samples prepared by dry ball milling. Using the turbomill as a leach vessel, it was found that 90.4 pct of the copper was extracted from the chalcopyrite during a 4-hour leach test in ferric sulfate versus conventional processing which involves either roasting of the ore for Cu recovery or leaching of the ore for several days.

  4. High-purity propionate production from glycerol in mixed culture fermentation.

    PubMed

    Chen, Yun; Wang, Ting; Shen, Nan; Zhang, Fang; Zeng, Raymond J

    2016-11-01

    High-purity propionate production from glycerol in mixed culture fermentation (MCF) induced by high ammonium concentration was investigated. Fed-batch experiments revealed that higher ammonium concentration (>2.9g/L) had simultaneous negative effects on acetate and propionate degradation. Propionate production and yield was up to 22.6g/L and 0.45g COD/g COD glycerol, respectively, with a purity of 96%. Sequential batch experiments demonstrated that the yields of propionate were 0.3±0.05, 0.32±0.01, and 0.34±0.03g COD/g COD at a glycerol concentration of 2.78, 4.38, and 5.56g/L, respectively, and the purity of propionate was 91-100%. Microbial community analysis showed that the phylum Firmicutes dominated the bacterial community at different glycerol concentrations. However, the Methanosaeta population decreased from 46% to 6% when glycerol concentration increased from 2.78 to 5.56g/L, resulting in lower acetate degradation rate. Thus, the present study might provide an alternative option for the production of propionate from glycerol via MCF.

  5. Water-Assisted Preparation of High-Purity Semiconducting (14,4) Carbon Nanotubes.

    PubMed

    Yang, Feng; Wang, Xiao; Si, Jia; Zhao, Xiulan; Qi, Kuo; Jin, Chuanhong; Zhang, Zeyao; Li, Meihui; Zhang, Daqi; Yang, Juan; Zhang, Zhiyong; Xu, Zhi; Peng, Lian-Mao; Bai, Xuedong; Li, Yan

    2017-01-24

    Semiconducting single-walled carbon nanotubes (s-SWNTs) with diameters of 1.0-1.5 nm (with similar bandgap to crystalline silicon) are highly desired for nanoelectronics. Up to date, the highest reported content of s-SWNTs as-grown is ∼97%, which is still far below the daunting requirements of high-end applications. Herein, we report a feasible and green pathway to use H2O vapor to modulate the structure of the intermetallic W6Co7 nanocrystals. By using the resultant W6Co7 nanocatalysts with a high percentage of (1 0 10) planes as structural templates, we realized the direct growth of s-SWNT with the purity of ∼99%, in which ∼97% is (14,4) tubes (diameter 1.29 nm). H2O can also act as an environmentally friendly and facile etchant for eliminating metallic SWNTs, and the content of s-SWNTs was further improved to 99.8% and (14,4) tubes to 98.6%. High purity s-SWNTs with even bandgap determined by their uniform structure can be used for the exquisite applications in different fields.

  6. Simulation study comparing high-purity germanium and cadmium zinc telluride detectors for breast imaging

    PubMed Central

    Campbell, DL; Peterson, TE

    2014-01-01

    We conducted simulations to compare the potential imaging performance for breast cancer detection with High-Purity Germanium (HPGe) and Cadmium Zinc Telluride (CZT) systems with 1% and 3.8% energy resolution at 140 keV, respectively. Using the Monte Carlo N-Particle (MCNP5) simulation package, we modelled both 5 mm-thick CZT and 10 mm-thick HPGe detectors with the same parallel-hole collimator for the imaging of a breast/torso phantom. Simulated energy spectra were generated, and planar images were created for various energy windows around the 140-keV photopeak. Relative sensitivity and scatter and the torso fractions were calculated along with tumour contrast and signal-to-noise ratios (SNR). Simulations showed that utilizing a ±1.25% energy window with an HPGe system better suppressed torso background and small-angle scattered photons than a comparable CZT system using a −5%/+10% energy window. Both systems provided statistically similar contrast and SNR, with HPGe providing higher relative sensitivity. Lowering the counts of HPGe images to match CZT count density still yielded equivalent contrast between HPGe and CZT. Thus, an HPGe system may provide equivalent breast imaging capability at lower injected radioactivity levels when acquiring for equal imaging time. PMID:25360792

  7. High-energy proton radiation damage of high-purity germanium detectors

    NASA Technical Reports Server (NTRS)

    Pehl, R. H.; Varnell, L. S.; Metzger, A. E.

    1978-01-01

    Quantitative studies of radiation damage in high-purity germanium gamma-ray detectors due to high-energy charged particles have been carried out; two 1.0 cm thick planar detectors were irradiated by 6 GeV/c protons. Under proton bombardment, degradation in the energy resolution was found to begin below 7 x 10 to the 7th protons/sq cm and increased proportionately in both detectors until the experiment was terminated at a total flux of 5.7 x 10 to the 8th protons/sq cm, equivalent to about a six year exposure to cosmic-ray protons in space. At the end of the irradiation, the FWHM resolution measured at 1332 keV stood at 8.5 and 13.6 keV, with both detectors of only marginal utility as a spectrometer due to the severe tailing caused by charge trapping. Annealing these detectors after proton damage was found to be much easier than after neutron damage.

  8. High-purity semi-insulating 4H-SiC for microwave device applications

    NASA Astrophysics Data System (ADS)

    Jenny, J. R.; Malta, D. P.; Müller, St G.; Powell, A. R.; Tsvetkov, V. F.; Hobgood, H. Mcd; Glass, R. C.; Carter, C. H., Jr.

    2003-05-01

    High-purity, semi-insulating (HPSI) 4H-SiC crystals with diameters up to 75 mm have been grown by the seeded sublimation technique without the intentional introduction of elemental deep-level dopants, such as vanadium. Wafers cut from these crystals exhibit homogeneous activation energies near mid gap and thermally stable semi-insulating (SI) behavior (>109 ohm-cm) throughout device processing. Secondary ion mass spectroscopy, deep-level transient spectroscopy, optical admittance spectroscopy, and electron paramagnetic resonance data suggest that the SI behavior originates from several deep levels associated with intrinsic point defects. Micropipe densities in HPSI substrates have been demonstrated to be as low as 10 cm-2 in 2-in. substrates, and the room-temperature thermal conductivity of this material is near the theoretical maximum of 5 W/cm·K for 4H-SiC. Devices fabricated on these HPSI wafers do not exhibit any substrate related back-gating effects and have power densities as high as 5.2 W/mm with 63% power added efficiency.

  9. Characterization of high purity lycopene from tomato wastes using a new pressurized extraction approach.

    PubMed

    Naviglio, Daniele; Caruso, Tonino; Iannece, Patrizia; Aragòn, Alejandro; Santini, Antonello

    2008-08-13

    In this paper, a method for the extraction of high purity lycopene from tomato wastes is presented. The method is based on a pressurized extraction that uses the Extractor Naviglio, and it is performed in the 0.7-0.9 MPa range. Tomato skin, the byproduct deriving from manufacturing of tomato, in a water dispersion, are used as starting material. Lycopene is transferred, for the effect of the high pressure used, in the form of molecular aggregates into the water as a dispersion, while apolar compounds remain in the matrix. The aggregates are easily purified in a single subsequent step by using methanol, thus, obtaining lycopene at 98% chromatographic purity or higher. A new stationary phase, phenyl-hexyl silicone, and a simple water/acetonitrile gradient were used for HPLC analysis of lycopene. The extract was characterized by UV-Vis spectrophotometry, (1)H NMR, (13)C NMR, and electrospray ionization mass spectrometry. An average recovery of 2.8 mg lycopene/kg tomato waste can be obtained after 4 hours of extraction and using tap water as the extracting liquid. The recovery percentage was of about 10%. The exhausted tomato byproduct can be easily dried and used in agriculture or as feeding for animals.

  10. Development and validation of a reversed-phase high-performance liquid chromatography method for routine identification and purity assessment of high-purity steviol glycoside sweeteners.

    PubMed

    Bililign, Tsion; Moore, Jeffrey C; Tan, Shane; Leeks, Allan T

    2014-02-12

    The widespread application of stevia-based sweeteners in food products has resulted in the need for reliable analytical methods for measuring the purity and identity of high-purity steviol glycoside ingredients. The objective of this research was to develop and validate a new reversed-phase separation method capable of separating and quantifying nine steviol glycosides present in typical high-purity stevia extract ingredients. Results of the study established the linearity of the method at a correlation factor of 1.000 for the two major components and other minor components of this food ingredient. Method accuracy values were in the range of 99.1-100.9%. The percent relative standard deviation for six independent assay determinations was 1.0%. The method was determined to be robust for minor changes in column temperature, initial acetonitrile content, flow rate, and wavelength. The validated high-performance liquid chromatography method was found to be suitable to be included by USP as a Food Chemicals Codex compendial standard for steviol glycosides.

  11. Dielectric Performance of High Purity HTCC Alumina at High Temperatures - A Comparison Study with Other Polycrystalline Alumina

    NASA Technical Reports Server (NTRS)

    Chen, Liang-Yu

    2012-01-01

    A very high purity (99.99+) high temperature co-fired ceramic (HTCC) alumina has recently become commercially available. The raw material of this HTCC alumina is very different from conventional HTCC alumina, and more importantly there is no glass additive in this co-fired material. Previously, selected HTCC and LTCC (low temperature co-fired ceramic) alumina materials were evaluated at high temperatures as dielectric and compared to a regularly sintered 96 polycrystalline alumina (96 Al2O3), where 96 alumina was used as the benchmark. A prototype packaging system based on regular 96 alumina with Au thick-film metallization successfully facilitated long term testing of high temperature silicon carbide (SiC) electronic devices for over 10,000 hours at 500C. In order to evaluate this new HTCC alumina for possible high temperature packaging applications, the dielectric properties of this HTCC alumina substrate were measured and compared with those of 96 alumina and a LTCC alumina from room temperature to 550C at frequencies of 120 Hz, 1 KHz, 10 KHz, 100 KHz, and 1 MHz. A parallel-plate capacitive device with dielectric of the HTCC alumina and precious metal electrodes were used for measurements of the dielectric constant and dielectric loss of the co-fired alumina material in the temperature and frequency ranges. The capacitance and AC parallel conductance of the capacitive device were directly measured by an AC impedance meter, and the dielectric constant and parallel AC conductivity of the dielectric were calculated from the capacitance and conductance measurement results. The temperature and frequency dependent dielectric constant, AC conductivity, and dissipation factor of the HTCC alumina substrate are presented and compared to those of 96 alumina. Other technical advantages of this new co-fired material for possible high packaging applications are also discussed.

  12. N-Type delta Doping of High-Purity Silicon Imaging Arrays

    NASA Technical Reports Server (NTRS)

    Blacksberg, Jordana; Hoenk, Michael; Nikzad, Shouleh

    2005-01-01

    A process for n-type (electron-donor) delta doping has shown promise as a means of modifying back-illuminated image detectors made from n-doped high-purity silicon to enable them to detect high-energy photons (ultraviolet and x-rays) and low-energy charged particles (electrons and ions). This process is applicable to imaging detectors of several types, including charge-coupled devices, hybrid devices, and complementary metal oxide/semiconductor detector arrays. Delta doping is so named because its density-vs.-depth characteristic is reminiscent of the Dirac delta function (impulse function): the dopant is highly concentrated in a very thin layer. Preferably, the dopant is concentrated in one or at most two atomic layers in a crystal plane and, therefore, delta doping is also known as atomic-plane doping. The use of doping to enable detection of high-energy photons and low-energy particles was reported in several prior NASA Tech Briefs articles. As described in more detail in those articles, the main benefit afforded by delta doping of a back-illuminated silicon detector is to eliminate a "dead" layer at the back surface of the silicon wherein high-energy photons and low-energy particles are absorbed without detection. An additional benefit is that the delta-doped layer can serve as a back-side electrical contact. Delta doping of p-type silicon detectors is well established. The development of the present process addresses concerns specific to the delta doping of high-purity silicon detectors, which are typically n-type. The present process involves relatively low temperatures, is fully compatible with other processes used to fabricate the detectors, and does not entail interruption of those processes. Indeed, this process can be the last stage in the fabrication of an imaging detector that has, in all other respects, already been fully processed, including metallized. This process includes molecular-beam epitaxy (MBE) for deposition of three layers, including

  13. High-Purity Nickel Prepared by Electron Beam Melting: Purification Mechanism

    NASA Astrophysics Data System (ADS)

    Zhang, Tao; Shang, Zaiyan; Chen, Ming; He, Jinjiang; Lv, Baoguo; Wang, Xingquan; Xiong, Xiaodong

    2013-12-01

    A bulk cylindrical high-purity nickel ingot, with purity of more than 99.999 pct (5N) in mass, was obtained from the raw nickel with 99.95 pct (3N5) initial purity by virtue of double electron beam melting (EBM). A chemical analysis was performed by using glow discharge mass spectrometry (GDMS) analysis for all elements in the periodic table except carbon, nitrogen, and oxygen, which were tested by the high-performance combustion and fusion method. The major impurities B, Na, Al, Si, P, S, Ca, Ti, Cr, Fe, Cu, Co, Zn, As, Ag, Sb, and Pb showed an excellent removal effect with removal efficiency of more than 85 pct following the double EBMs. Li, Mg, Cl, K, V, Mn, Ga, Ge, Cd, Se, In, Sn, Tl, Au, and Pt were below the detection limit. No significant change in concentration was found for the refractory elements W, Mo, Ta, Nb, and Ir. Be, F, Sc, Se, Br, Rb, Sr, Zr, Y, Ru, Rh, Pd, Te, I, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Re, Os, Hg, Bi, Th, and U were not detectable following the purification as compared to the raw nickel. Gaseous impurities, C, N, O, especially for N, was removed sufficiently. Theoretical calculations for removal efficiency of impurity Fe based on the calculated vapor pressure, activity coefficient, and melt temperature were in good agreement with measured results, and the purification mechanism was ascribed to the evaporation of major impurities and subsequently evacuation by repetitive EBM.

  14. Evaluation of Prebiotic Effects of High-Purity Galactooligosaccharides in vitro and in vivo

    PubMed Central

    Hong, Ki Bae; Kim, Jae Hwan; Kwon, Hyuk Kon; Han, Sung Hee

    2016-01-01

    Summary Galactooligosaccharides (GOS) are an important class of dietary prebiotics that exert beneficial effects on intestinal microbiota and gut barrier function. In this study, high-purity GOS (HP-GOS) were investigated in vitro and in vivo and confirmed as prebiotic ingredients in rat diet. HP-GOS were successfully produced using a two-step process, enzymatic hydrolysis and fermentation by yeast. They were found to serve as a good substrate and carbon source for supporting the growth of probiotic bacteria more effectively than other commercial GOS. Following administration of 1% (by mass) of HP-GOS to rats, the growth of Bifidobacterium bifidum and B. longum in the gut increased most rapidly up to 12 h, and thereafter the increase was slow. Therefore, 1% HP-GOS was found to be acceptable for the growth of probiotic bacteria. Groups of animals that were orally administered HP-GOS and bifidobacteria during the study, and the group administered HP-GOS during the 2nd (days 13–15) and 4th (days 28–30) period of the study had significantly (p<0.05) higher numbers of bifidobacteria in faeces than groups receiving a single dose of bifidobacteria. HP-GOS affected the expression of genes encoding glucagon-like peptide-1 (GLP-1) and peptide YY (PYY). There was a significant upregulation of GLP-1 and PYY mRNA with HP-GOS and bifidobacteria intake. We propose that the prebiotic properties of HP-GOS are potentially valuable for the production of functional foods for human consumption. PMID:27904405

  15. Raman and photoelectron spectroscopic investigation of high-purity niobium materials: Oxides, hydrides, and hydrocarbons

    NASA Astrophysics Data System (ADS)

    Singh, Nageshwar; Deo, M. N.; Nand, Mangla; Jha, S. N.; Roy, S. B.

    2016-09-01

    We present investigations of the presence of oxides, hydrides, and hydrocarbons in high-purity (residual resistivity ratio, ˜300) niobium (Nb) materials used in fabrication of superconducting radio frequency (SRF) cavities for particle accelerators. Raman spectroscopy of Nb materials (as-received from the vendor as well as after surface chemical- and thermal processing) revealed numerous peaks, which evidently show the presence of oxides (550 cm-1), hydrides (1277 and 1385 cm-1: ˜80 K temperature), and groups of hydrocarbons (1096, 2330, 2710, 2830, 2868, and 3080 cm-1). The present work provides direct spectroscopic evidence of hydrides in the electropolished Nb materials typically used in SRF cavities. Raman spectroscopy thus can provide vital information about the near-surface chemical species in niobium materials and will help in identifying the cause for the performance degradation of SRF cavities. Furthermore, photoelectron spectroscopy was performed on the Nb samples to complement the Raman spectroscopy study. This study reveals the presence of C and O in the Nb samples. Core level spectra of Nb (doublet 3d5/2 and 3d3/2) show peaks near 206.6 and 209.4 eV, which can be attributed to the Nb5+ oxidation state. The core level spectra of C 1 s of the samples are dominated by graphitic carbon (binding energy, 284.6 eV), while the spectra of O 1 s are asymmetrically peaked near binding energy of ˜529 eV, and that indicates the presence of metal-oxide Nb2O5. The valence-band spectra of the Nb samples are dominated by a broad peak similar to O 2p states, but after sputtering (for 10 min) a peak appears at ˜1 eV, which is a feature of the elemental Nb atom.

  16. High-purity 3D nano-objects grown by focused-electron-beam induced deposition

    NASA Astrophysics Data System (ADS)

    Córdoba, Rosa; Sharma, Nidhi; Kölling, Sebastian; Koenraad, Paul M.; Koopmans, Bert

    2016-09-01

    To increase the efficiency of current electronics, a specific challenge for the next generation of memory, sensing and logic devices is to find suitable strategies to move from two- to three-dimensional (3D) architectures. However, the creation of real 3D nano-objects is not trivial. Emerging non-conventional nanofabrication tools are required for this purpose. One attractive method is focused-electron-beam induced deposition (FEBID), a direct-write process of 3D nano-objects. Here, we grow 3D iron and cobalt nanopillars by FEBID using diiron nonacarbonyl Fe2(CO)9, and dicobalt octacarbonyl Co2(CO)8, respectively, as starting materials. In addition, we systematically study the composition of these nanopillars at the sub-nanometer scale by atom probe tomography, explicitly mapping the homogeneity of the radial and longitudinal composition distributions. We show a way of fabricating high-purity 3D vertical nanostructures of ˜50 nm in diameter and a few micrometers in length. Our results suggest that the purity of such 3D nanoelements (above 90 at% Fe and above 95 at% Co) is directly linked to their growth regime, in which the selected deposition conditions are crucial for the final quality of the nanostructure. Moreover, we demonstrate that FEBID and the proposed characterization technique not only allow for growth and chemical analysis of single-element structures, but also offers a new way to directly study 3D core-shell architectures. This straightforward concept could establish a promising route to the design of 3D elements for future nano-electronic devices.

  17. Crystallization and preliminary X-ray analysis of coagulation factor IX-binding protein from habu snake venom at pH 6.5 and 4.6

    SciTech Connect

    Suzuki, Nobuhiro; Shikamoto, Yasuo; Fujimoto, Zui; Morita, Takashi; Mizuno, Hiroshi

    2005-01-01

    Crystals of habu coagulation factor IX-binding protein have been obtained at pH 6.5 and 4.6 and characterized by X-ray diffraction. Coagulation factor IX-binding protein isolated from Trimeresurus flavoviridis (IX-bp) is a C-type lectin-like protein. It is an anticoagulant protein consisting of homologous subunits A and B. The subunits both contain a Ca{sup 2+}-binding site with differing affinity (K{sub d} values of 14 and 130 µM at pH 7.5). These binding characteristics are pH-dependent; under acidic conditions, the affinity of the low-affinity site was reduced considerably. In order to identify which site has high affinity and also to investigate the Ca{sup 2+}-releasing mechanism, IX-bp was crystallized at pH 6.5 and 4.6. The crystals at pH 6.5 and 4.6 diffracted to 1.72 and 2.29 Å resolution, respectively; the former crystals belong to the monoclinic space group P2{sub 1}, with unit-cell parameters a = 60.7, b = 63.5, c = 66.9 Å, β = 117.0°, while the latter belong to the monoclinic space group C2, with a = 134.1, b = 37.8, c = 55.8 Å, β = 110.4°.

  18. The three-dimensional structure of the first EGF-like module of human factor IX: comparison with EGF and TGF-alpha.

    PubMed

    Baron, M; Norman, D G; Harvey, T S; Handford, P A; Mayhew, M; Tse, A G; Brownlee, G G; Campbell, I D

    1992-01-01

    The three-dimensional structure of the first epidermal growth factor (EGF)-like module from human factor IX has been determined in solution using two-dimensional nuclear magnetic resonance (in the absence of calcium and at pH 4.5). The structure was found to resemble closely that of EGF and the homologous transforming growth factor-alpha (TGF-alpha). Residues 60-65 form an antiparallel beta-sheet with residues 68-73. In the C-terminal subdomain a type II beta-turn is found between residues 74 and 77 and a five-residue turn is found between residues 79 and 83. Glu 78 and Leu 84 pair in an antiparallel beta-sheet conformation. In the N-terminal region a loop is found between residues 50 and 55 such that the side chains of both are positioned above the face of the beta-sheet. Residues 56-60 form a turn that leads into the first strand of the beta-sheet. Whereas the global fold closely resembles that of EGF, the N-terminal residues of the module (46-49) do not form a beta-strand but are ill-defined in the structure, probably due to the local flexibility of this region. The structure is discussed with reference to recent site-directed mutagenesis data, which have identified certain conserved residues as ligands for calcium.

  19. Diffusion bonding and brazing of high purity copper for linear collider accelerator structures

    NASA Astrophysics Data System (ADS)

    Elmer, J. W.; Klingmann, J.; van Bibber, K.

    2001-05-01

    Diffusion bonding and brazing of high purity copper were investigated to develop procedures for joining precision machined copper components for the Next Linear Collider (NLC). Diffusion bonds were made over a range of temperatures from 400 °C to 1000 °C, under two different loading conditions [3.45 kPa (0.5 psi) and 3.45 MPa (500 psi)], and on two different diamond machined surface finishes. Brazes were made using pure silver, pure gold, and gold-nickel alloys, and different heating rates produced by both radiation and induction heating. Braze materials were applied by both physical vapor deposition (PVD) and conventional braze alloy shims. Results of the diffusion bonding experiments showed that bond strengths very near that of the copper base metal could be made at bonding temperatures of 700 °C or higher at 3.45 MPa bonding pressure. At lower temperatures, only partial strength diffusion bonds could be made. At low bonding pressures (3.45 kPa), full strength bonds were made at temperatures of 800 °C and higher, while no bonding (zero strength) was observed at temperatures of 700 °C and lower. Observations of the fracture surfaces of the diffusion bonded samples showed the effects of surface finish on the bonding mechanism. These observations clearly indicate that bonding began by point asperity contact, and flatter surfaces resulted in a higher percentage of bonded area under similar bonding conditions. Results of the brazing experiments indicated that pure silver worked very well for brazing under both conventional and high heating rate scenarios. Similarly, pure silver brazed well for both the PVD layers and the braze alloy shims. The gold and gold-containing brazes had problems, mainly due to the high diffusivity of gold in copper. These problems led to the necessity of overdriving the temperature to ensure melting, the presence of porosity in the joint, and very wide braze joints. Based on the overall findings of this study, a two-step joining method

  20. High-Purity Aluminum Magnet Technology for Advanced Space Transportation Systems

    NASA Technical Reports Server (NTRS)

    Goodrich, R. G.; Pullam, B.; Rickle, D.; Litchford, R. J.; Robertson, G. A.; Schmidt, D. D.; Cole, John (Technical Monitor)

    2001-01-01

    Basic research on advanced plasma-based propulsion systems is routinely focused on plasmadynamics, performance, and efficiency aspects while relegating the development of critical enabling technologies, such as flight-weight magnets, to follow-on development work. Unfortunately, the low technology readiness levels (TRLs) associated with critical enabling technologies tend to be perceived as an indicator of high technical risk, and this, in turn, hampers the acceptance of advanced system architectures for flight development. Consequently, there is growing recognition that applied research on the critical enabling technologies needs to be conducted hand in hand with basic research activities. The development of flight-weight magnet technology, for example, is one area of applied research having broad crosscutting applications to a number of advanced propulsion system architectures. Therefore, NASA Marshall Space Flight Center, Louisiana State University (LSU), and the National High Magnetic Field Laboratory (NHMFL) have initiated an applied research project aimed at advancing the TRL of flight-weight magnets. This Technical Publication reports on the group's initial effort to demonstrate the feasibility of cryogenic high-purity aluminum magnet technology and describes the design, construction, and testing of a 6-in-diameter by 12-in-long aluminum solenoid magnet. The coil was constructed in the machine shop of the Department of Physics and Astronomy at LSU and testing was conducted in NHMFL facilities at Florida State University and at Los Alamos National Laboratory. The solenoid magnet was first wound, reinforced, potted in high thermal conductivity epoxy, and bench tested in the LSU laboratories. A cryogenic container for operation at 77 K was also constructed and mated to the solenoid. The coil was then taken to NHMFL facilities in Tallahassee, FL. where its magnetoresistance was measured in a 77 K environment under steady magnetic fields as high as 10 T. In

  1. Desensitization and immune tolerance induction in children with severe factor IX deficiency; inhibitors and adverse reactions to replacement therapy: a case-report and literature review.

    PubMed

    Bon, Andrea; Morfini, Massimo; Dini, Alessandro; Mori, Francesca; Barni, Simona; Gianluca, Sottilotta; de Martino, Maurizio; Novembre, Elio

    2015-02-19

    Hemophilia B is a rare X-linked recessive disorder with plasma factor IX (FIX) deficiency. 1-3% of patients treated with exogenous FIX-containing products develop inhibitors (i.e. polyclonal high affinity immunoglobulins) that neutralize the procoagulant activity of a specific coagulation factor. Although the incidence of inhibitors in hemophilia B patients is low, most are "high titer" and frequently associated with the development of severe allergic or anaphylactic reactions. Immune tolerance induction as a strategy for inhibitor eradication was first described in 1984. Unfortunately, the overall reported success of immune tolerance induction in FIX deficiency with inhibitors is approximately 25-40%.We report the case of a 2-year-old boy with hemophilia B severe FIX deficiency (<1%), inhibitor antibodies to FIX development, and a history of adverse reactions to FIX infusions, who underwent a successful desensitization and immune tolerance induction with a daily FIX infusion. With this regimen the inhibitor titer decreased with effective bleeding prevention.

  2. Characterization of high-purity niobium structures fabricated using the electron beam melting process

    NASA Astrophysics Data System (ADS)

    Terrazas Najera, Cesar Adrian

    Additive Manufacturing (AM) refers to the varied set of technologies utilized for the fabrication of complex 3D components from digital data in a layer-by-layer fashion. The use of these technologies promises to revolutionize the manufacturing industry. The electron beam melting (EBM) process has been utilized for the fabrication of fully dense near-net-shape components from various metallic materials. This process, catalogued as a powder bed fusion technology, consists of the deposition of thin layers (50 - 120microm) of metallic powder particles which are fused by the use of a high energy electron beam and has been commercialized by Swedish company Arcam AB. Superconducting radio frequency (SRF) cavities are key components that are used in linear accelerators and other light sources for studies of elemental physics. Currently, cavity fabrication is done by employing different forming processes including deep-drawing and spinning. In both of the latter techniques, a feedstock high-purity niobium sheet with a thickness ranging from 3-4 mm is mechanically deformed and shaped into the desired geometry. In this manner, half cavities are formed that are later joined by electron beam welding (EBW). The welding step causes variability in the shape of the cavity and can also introduce impurities at the surface of the weld interface. The processing route and the purity of niobium are also of utmost importance since the presence of impurities such as inclusions or defects can be detrimental for the SRF properties of cavities. The focus of this research was the use of the EBM process in the manufacture of high purity niobium parts with potential SRF applications. Reactor grade niobium was plasma atomized and used as the precursor material for fabrication using EBM. An Arcam A2 system was utilized for the fabrication. The system had all internal components of the fabrication chamber replaced and was cleaned to prevent contamination of niobium powder. A mini-vat, developed at

  3. Matrix elimination ion chromatography method for the determination of trace levels of anionic impurities in high purity cesium iodide.

    PubMed

    Ayushi; Kumar, Sangita D; Reddy, A V R

    2012-01-01

    In the present study an ion chromatographic method based on matrix elimination has been developed for the determination of anionic impurities in high purity cesium iodide crystals. The presence of impurities has a detrimental effect on the characteristics of detectors based on cesium iodide crystals. In particular, oxygen-containing anions inhibit the resolving power of scintillators and decrease the optical absorption. The quantitative determination of anions (fluoride, chloride, bromide, nitrate, phosphate, and sulphate) simultaneously in the high-purity cesium iodide crystals has not been carried out before. The large concentration of iodide poses a challenge in the determination of anions (especially phosphate and sulphate); hence, matrix elimination is accomplished by adopting a sample pretreatment technique. The method is validated for linearity, accuracy, and precision. The limit of detection for different anions is in the range of 0.3-3 µg/g, and the relative standard deviation is in the range of 4-6% for the overall method.

  4. A facile route to preparation of high purity nanoporous silica from acid-leached residue of serpentine.

    PubMed

    Bai, Penn; Sharratt, Paul; Yeo, Tze Yuen; Bu, Jie

    2014-09-01

    As the current cost of mineral carbonation is too high for an economically viable industrial process, it is desirable to produce value-added products from CO2 mineralization process. In this work, a facile and cost-effective process was developed for the production of high purity SiO2 from acid-leached serpentine residue. The Si extraction rate is fast even under ambient conditions due to the highly defective structure of the residue. The reaction kinetics were studied and it was found that the Si extraction rate was under a combination of chemical reaction control and film diffusion control. The SiO2 sample prepared has high purity with a nanoporous structure, which renders it a potential candidate for applications such as an adsorbent and a catalyst support.

  5. Intra- and inter-tube exciton relaxation dynamics in high purity semiconducting and metallic single-walled carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Ichida, Masao; Saito, Shingo; Miyata, Yasumitsu; Yanagi, Kazuhiro; Kataura, Hiromichi; Ando, Hiroaki

    2013-02-01

    We have measured the exciton and carrier dynamics in the high purity semiconducting (S-) and metallic (M-) single-walled carbon nanotubes (SWNTs) in the isolated and aggregated (bundled) forms. The exciton relaxation decay times are measured by using the pump-probe spectroscopy. For bundled samples, the relaxation time becomes shorter than that for isolated SWNTs sample, because of the existence of inter-tube relaxation. We estimate the relaxation rates from S-SWNT to S-SWNT and S-SWNT to M-SWNT using the decay times for isolated SWNTs, high purity S-SWNTs bundle, and doped S-SWNTs in high purity M-SWNTs bundle. For S-SWNTs, inter-tube relaxation plays an important role in the relaxation dynamics. However, for M-SWNTs, the inter-tube relaxation is not so important, and the transition energy and intensity of exciton in M-SWNTs is strongly affected by the photoexcited carriers which plays like as photo doping.

  6. Fabrication process development for high-purity germanium radiation detectors with amorphous semiconductor contacts

    NASA Astrophysics Data System (ADS)

    Looker, Quinn

    High-purity germanium (HPGe) radiation detectors are well established as a valuable tool in nuclear science, astrophysics, and nuclear security applications. HPGe detectors excel in gamma-ray spectroscopy, offering excellent energy resolution with large detector sizes for high radiation detection efficiency. Although a robust fabrication process has been developed, improvement is needed, especially in developing electrical contact and surface passivation technology for position-sensitive detectors. A systematic study is needed to understand how the detector fabrication process impacts detector performance and reliability. In order to provide position sensitivity, the electrical contacts are segmented to form multiple electrodes. This segmentation creates new challenges in the fabrication process and warrants consideration of additional detector effects related to the segmentation. A key area of development is the creation of the electrical contacts in a way that enables reliable operation, provides low electronic noise, and allows fine segmentation of electrodes, giving position sensitivity for radiation interactions in the detector. Amorphous semiconductor contacts have great potential to facilitate new HPGe detector designs by providing a thin, high-resistivity surface coating that is the basis for electrical contacts that block both electrons and holes and can easily be finely segmented. Additionally, amorphous semiconductor coatings form a suitable passivation layer to protect the HPGe crystal surface from contamination. This versatility allows a simple fabrication process for fully passivated, finely segmented detectors. However, the fabrication process for detectors with amorphous semiconductors is not as highly developed as for conventional technologies. The amorphous semiconductor layer properties can vary widely based on how they are created and these can translate into varying performance of HPGe detectors with these contacts. Some key challenges include

  7. Intercollegiate Athletics and Title IX

    ERIC Educational Resources Information Center

    Cox, Thomas A.

    1977-01-01

    The application of Title IX and the HEW regulation to intercollegiate sports is described, and the relationships among Title IX, the equal protection doctrine, and the proposed equal rights amendment to the Constitution are assessed. (LBH)

  8. 40 CFR Appendix Ix to Part 86 - Experimentally Determining the R-Factor for Bench Aging Durability Procedures

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... the R-Factor for Bench Aging Durability Procedures The R-Factor is the catalyst thermal reactivity... several catalysts (minimum of 3 of the same catalyst design) at different control temperatures between the normal operating temperature and the damage limit temperature. Measure emissions (or...

  9. 40 CFR Appendix Ix to Part 86 - Experimentally Determining the R-Factor for Bench Aging Durability Procedures

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... the R-Factor for Bench Aging Durability Procedures The R-Factor is the catalyst thermal reactivity... several catalysts (minimum of 3 of the same catalyst design) at different control temperatures between the normal operating temperature and the damage limit temperature. Measure emissions (or...

  10. 40 CFR Appendix Ix to Part 86 - Experimentally Determining the R-Factor for Bench Aging Durability Procedures

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-Factor for Bench Aging Durability Procedures The R-Factor is the catalyst thermal reactivity coefficient... several catalysts (minimum of 3 of the same catalyst design) at different control temperatures between the normal operating temperature and the damage limit temperature. Measure emissions (or...

  11. Functionally important regions of the factor IX gene have a low rate of polymorphism and a high rate of mutation in the dinucleotide CpG.

    PubMed Central

    Koeberl, D D; Bottema, C D; Buerstedde, J M; Sommer, S S

    1989-01-01

    We have recently described genomic amplification with transcript sequencing (GAWTS), a three-step procedure that allows direct genomic sequencing. By GAWTS more than 100,000 bp of sequence have been generated from eight regions of the factor IX gene, which include the putative promoter region, the coding region, and the splice junctions. All eight regions were examined in 20 unrelated normal individuals of defined ethnicity and subsequently in 22 hemophiliacs in different families. The following three major conclusions emerge: (1) The rate of polymorphism in these eight regions of functional significance has been measured in an X-linked gene, and it is about one-third of the average rate observed for intronic and intergenic sequences on the X chromosome. The rate is low enough that the causative mutation should be the only sequence change seen in the overwhelming majority of hemophiliacs. (2) Transitions of CpG account for 31% (5/16) of the distinct mutations and for 38% (5/13) of the single-base changes. The rate of transitions at CpG is elevated by an estimated 77-fold, presumably owing to lack of repair of thymidine generated by the spontaneous deamination of 5-methylcytidine. (3) High-quality, reproducible sequence data can be obtained on a time scale that makes direct carrier testing and prenatal diagnosis feasible. Images Figure 3 PMID:2773937

  12. The rates of G:C[yields]T:A and G:C[yields]C:G transversions at CpG dinucleotides in the human factor IX gene

    SciTech Connect

    Ketterling, R.P.; Vielhaber, E.; Sommer, S.S. )

    1994-05-01

    The authors have identified eight independent transversions at CpG in 290 consecutive families with hemophilia B. These eight transversions account for 16.3% of all independent transversions in the sample, yet the expected frequency of CpG transversions at random in the factor IX gene is only 2.6% (P<0.1). The aggregate data suggest that the two types of CpG transversions (G:C[yields]T:A and G:C[yields]C:G) possess similar mutation rates (24.8 [times] 10[sup [minus]10] and 20.6 [times] 10[sup [minus]10], respectively), which are about fivefold greater than the comparable rates for transversions at non-CpG dinucleotides. The enhancement of transversions at CpG suggest that the model by which mutations occur at CpG may need to be reevaluated. The relationship, if any, between deamination of 5-methyl cytosine and enhancement of transversions at CpG remains to be defined. 28 refs., 2 tabs.

  13. Novel electric power-driven hydrodynamic injection system for gene delivery: safety and efficacy of human factor IX delivery in rats.

    PubMed

    Yokoo, T; Kamimura, K; Suda, T; Kanefuji, T; Oda, M; Zhang, G; Liu, D; Aoyagi, Y

    2013-08-01

    The development of a safe and reproducible gene delivery system is an essential step toward the clinical application of the hydrodynamic gene delivery (HGD) method. For this purpose, we have developed a novel electric power-driven injection system called the HydroJector-EM, which can replicate various time-pressure curves preloaded into the computer program before injection. The assessment of the reproducibility and safety of gene delivery system in vitro and in vivo demonstrated the precise replication of intravascular time-pressure curves and the reproducibility of gene delivery efficiency. The highest level of luciferase expression (272 pg luciferase per mg of proteins) was achieved safely using the time-pressure curve, which reaches 30 mm Hg in 10 s among various curves tested. Using this curve, the sustained expression of a therapeutic level of human factor IX protein (>500 ng ml(-1)) was maintained for 2 months after the HGD of the pBS-HCRHP-FIXIA plasmid. Other than a transient increase in liver enzymes that recovered in a few days, no adverse events were seen in rats. These results confirm the effectiveness of the HydroJector-EM for reproducible gene delivery and demonstrate that long-term therapeutic gene expression can be achieved by automatic computer-controlled hydrodynamic injection that can be performed by anyone.

  14. Roles of Carbonic Anhydrase IX in Development of Pancreatic Cancer.

    PubMed

    Li, Yuji; Dong, Ming; Sheng, Weiwei; Huang, Longping

    2016-04-01

    The aim of this study was to study the effects of carbonic anhydrase IX (CA IX) towards the invasion and metastasis of pancreatic cancer. The expressions of CA IX in 58 cases of pancreatic cancer and paired paracancerous normal tissues, obtained from 2005 to 2012 in the first Affiliated Hospital of China Medical University, were detected, as well as its expressions in different pancreatic cancer cell lines, aiming to detect the impacts of CA IX silencing towards the invasion and metastasis of pancreatic cancer cells. The CA IX expressions in 58 pancreatic cancer cases were higher than those in the paired paracancerous normal tissues (P < 0.01), and positively correlated with the tumor size and the UICC staging UICC (P < 0.05), the multivariate analysis showed that the high expression of CA IX was the independent risk factor towards the prognosis of pancreatic cancer (P < 0.05). The CA IX was highly expressed in AxPC-1 and Miapaca-2, and the interference effects were significant. CA IX silencing could significantly inhibit the invasion and metastasis of AxPC-1 and Miapaca. We support a pro-tumor role of CA IX in the development and progression of pancreatic cancer.

  15. High Purity Hydrogen Production with In-Situ Carbon Dioxide and Sulfur Capture in a Single Stage Reactor

    SciTech Connect

    Nihar Phalak; Shwetha Ramkumar; Daniel Connell; Zhenchao Sun; Fu-Chen Yu; Niranjani Deshpande; Robert Statnick; Liang-Shih Fan

    2011-07-31

    Enhancement in the production of high purity hydrogen (H{sub 2}) from fuel gas, obtained from coal gasification, is limited by thermodynamics of the water gas shift (WGS) reaction. However, this constraint can be overcome by conducting the WGS in the presence of a CO{sub 2}-acceptor. The continuous removal of CO{sub 2} from the reaction mixture helps to drive the equilibrium-limited WGS reaction forward. Since calcium oxide (CaO) exhibits high CO{sub 2} capture capacity as compared to other sorbents, it is an ideal candidate for such a technique. The Calcium Looping Process (CLP) developed at The Ohio State University (OSU) utilizes the above concept to enable high purity H{sub 2} production from synthesis gas (syngas) derived from coal gasification. The CLP integrates the WGS reaction with insitu CO{sub 2}, sulfur and halide removal at high temperatures while eliminating the need for a WGS catalyst, thus reducing the overall footprint of the hydrogen production process. The CLP comprises three reactors - the carbonator, where the thermodynamic constraint of the WGS reaction is overcome by the constant removal of CO{sub 2} product and high purity H{sub 2} is produced with contaminant removal; the calciner, where the calcium sorbent is regenerated and a sequestration-ready CO{sub 2} stream is produced; and the hydrator, where the calcined sorbent is reactivated to improve its recyclability. As a part of this project, the CLP was extensively investigated by performing experiments at lab-, bench- and subpilot-scale setups. A comprehensive techno-economic analysis was also conducted to determine the feasibility of the CLP at commercial scale. This report provides a detailed account of all the results obtained during the project period.

  16. Using standard calibrated geometries to characterize a coaxial high purity germanium gamma detector for Monte Carlo simulations

    NASA Astrophysics Data System (ADS)

    van der Graaf, E. R.; Dendooven, P.; Brandenburg, S.

    2014-06-01

    A detector model optimization procedure based on matching Monte Carlo simulations with measurements for two experimentally calibrated sample geometries which are frequently used in radioactivity measurement laboratories results in relative agreement within 5% between simulated and measured efficiencies for a high purity germanium detector. The optimization procedure indicated that the increase in dead layer thickness is largely responsible for a detector efficiency decrease in time. The optimized detector model allows Monte Carlo efficiency calibration for all other samples of which the geometry and bulk composition is known. The presented method is a competitive and economic alternative to more elaborate detector scanning methods and results in a comparable accuracy.

  17. Using standard calibrated geometries to characterize a coaxial high purity germanium gamma detector for Monte Carlo simulations.

    PubMed

    van der Graaf, E R; Dendooven, P; Brandenburg, S

    2014-06-01

    A detector model optimization procedure based on matching Monte Carlo simulations with measurements for two experimentally calibrated sample geometries which are frequently used in radioactivity measurement laboratories results in relative agreement within 5% between simulated and measured efficiencies for a high purity germanium detector. The optimization procedure indicated that the increase in dead layer thickness is largely responsible for a detector efficiency decrease in time. The optimized detector model allows Monte Carlo efficiency calibration for all other samples of which the geometry and bulk composition is known. The presented method is a competitive and economic alternative to more elaborate detector scanning methods and results in a comparable accuracy.

  18. Magnetic and magnetothermal properties and the magnetic phase diagram of high purity single crystalline terbium along the easy magnetization direction

    SciTech Connect

    Zverev, V. I.; Tishin, A. M.; Chernyshov, A. S.; Mudryk, Ya; Gschneidner Jr., Karl A.; Pecharsky, Vitalij K.

    2014-01-21

    The magnetic and magnetothermal properties of a high purity terbium single crystal have been re-investigated from 1.5 to 350 K in magnetic fields ranging from 0 to 75 kOe using magnetization, ac magnetic susceptibility and heat capacity measurements. The magnetic phase diagram has been refined by establishing a region of the fan-like phase broader than reported in the past, by locating a tricritical point at 226 K, and by a more accurate definition of the critical fields and temperatures associated with the magnetic phases observed in Tb.

  19. Using standard calibrated geometries to characterize a coaxial high purity germanium gamma detector for Monte Carlo simulations

    SciTech Connect

    Graaf, E. R. van der Dendooven, P.; Brandenburg, S.

    2014-06-15

    A detector model optimization procedure based on matching Monte Carlo simulations with measurements for two experimentally calibrated sample geometries which are frequently used in radioactivity measurement laboratories results in relative agreement within 5% between simulated and measured efficiencies for a high purity germanium detector. The optimization procedure indicated that the increase in dead layer thickness is largely responsible for a detector efficiency decrease in time. The optimized detector model allows Monte Carlo efficiency calibration for all other samples of which the geometry and bulk composition is known. The presented method is a competitive and economic alternative to more elaborate detector scanning methods and results in a comparable accuracy.

  20. Gas chromatographic separation of nitrogen, oxygen, argon, and carbon monoxide using custom-made porous polymers from high purity divinylbenzene

    NASA Technical Reports Server (NTRS)

    Pollock, G. E.; Ohara, D.; Hollis, O. L.

    1984-01-01

    Existing porous polymers were surveyed for their ability to separate the subject gases. Certain products that showed more promise than others were synthesized and the existing synthetic procedures studied and modified to produce new polymers with enhanced ability to separate the subject gases. Evaluation of the porous polymers was carried out practically by gas chromatography at ambient temperature. The modified synthetic procedures were somewhat simpler than the originals. The new porous polymers made with high purity divinylbenzene enabled use of shorter columns to obtain the separations desired.

  1. High-purity hydrogen generation by ultraviolet illumination with the membrane composed of titanium dioxide nanotube array and Pd layer

    NASA Astrophysics Data System (ADS)

    Hattori, Masashi; Noda, Kei; Matsushige, Kazumi

    2011-09-01

    High-purity hydrogen generation was observed by using a membrane composed of a bilayer of an anodized titanium dioxide nanotube array (TNA) and a hydrogen permeable metal. This membrane was fabricated by transferring a TNA embedded in a titanium foil onto a sputtered 10-μm-thick palladium film. Alcohols are reformed photocatalytically and concurrently generated hydrogen is purified through the Pd layer. H2 with a purity of more than 99% was obtained from liquid alcohols under ultraviolet illumination onto the membrane. Thus, we demonstrated the integration of photocatalytic hydrogen production and purification within a single membrane.

  2. Rapid Single-Stage Separation of Micrometer-Long and High-Purity Semiconducting Carbon Nanotubes by Gel Filtration

    NASA Astrophysics Data System (ADS)

    Thendie, Boanerges; Miyata, Yasumitsu; Kitaura, Ryo; Miyauchi, Yuhei; Matsuda, Kazunari; Shinohara, Hisanori

    2013-06-01

    We demonstrate the separation of high-purity, long semiconducting single-wall carbon nanotubes (s-SWCNTs) by single-stage gel filtration. Semiconducting SWCNTs are preferentially adsorbed on an allyl dextran-based gel column and then eluted with surfactant solution at a rate that depends on nanotube length as well as electronic type of nanotubes. These differences allow the separation of length-sorted and purity-enhanced s-SWCNTs by fractionated collection of the eluate, which provides the desired nanotubes for electronic device applications.

  3. Processing and properties of high-purity, fine-grain-size depleted-uranium, deep-drawn shapes

    SciTech Connect

    Jackson, R J; Lundberg, M R; Bruchey, W L

    1980-10-01

    Unalloyed uranium is a candidate material for shaped charge liners used in conventional ordinance applications. For test purposes, it was decided that a high-grade uranium material with good toughness should be used. This report describes a process for producing a high-purity (less than 500 ppM total impurities) wrought material consisting of a recrystallized, equiaxed grain structure with a 10 micron (ASTM-8) average grain size. The fabrication process is discussed in detail. In all, six material conditions having a wide range of mechanical and structural properties were investigated. The tensile, hardness, and microstructural properties of these six material conditions are reported in detail.

  4. Preparation of uniform nanoparticles of ultra-high purity metal oxides, mixed metal oxides, metals, and metal alloys

    DOEpatents

    Woodfield, Brian F.; Liu, Shengfeng; Boerio-Goates, Juliana; Liu, Qingyuan; Smith, Stacey Janel

    2012-07-03

    In preferred embodiments, metal nanoparticles, mixed-metal (alloy) nanoparticles, metal oxide nanoparticles and mixed-metal oxide nanoparticles are provided. According to embodiments, the nanoparticles may possess narrow size distributions and high purities. In certain preferred embodiments, methods of preparing metal nanoparticles, mixed-metal nanoparticles, metal oxide nanoparticles and mixed-metal nanoparticles are provided. These methods may provide tight control of particle size, size distribution, and oxidation state. Other preferred embodiments relate to a precursor material that may be used to form nanoparticles. In addition, products prepared from such nanoparticles are disclosed.

  5. Recombinant factor IX-Fc fusion protein (rFIXFc) demonstrates safety and prolonged activity in a phase 1/2a study in hemophilia B patients

    PubMed Central

    Ragni, Margaret V.; Valentino, Leonard A.; Key, Nigel S.; Josephson, Neil C.; Powell, Jerry S.; Cheng, Gregory; Thompson, Arthur R.; Goyal, Jaya; Tubridy, Karen L.; Peters, Robert T.; Dumont, Jennifer A.; Euwart, Donald; Li, Lian; Hallén, Bengt; Gozzi, Peter; Bitonti, Alan J.; Jiang, Haiyan; Luk, Alvin

    2012-01-01

    Current factor IX (FIX) products display a half-life (t1/2) of ∼ 18 hours, requiring frequent intravenous infusions for prophylaxis and treatment in patients with hemophilia B. This open-label, dose-escalation trial in previously treated adult subjects with hemophilia B examined the safety and pharmacokinetics of rFIXFc. rFIXFc is a recombinant fusion protein composed of FIX and the Fc domain of human IgG1, to extend circulating time. Fourteen subjects received a single dose of rFIXFc; 1 subject each received 1, 5, 12.5, or 25 IU/kg, and 5 subjects each received 50 or 100 IU/kg. rFIXFc was well tolerated, and most adverse events were mild or moderate in intensity. No inhibitors were detected in any subject. Dose-proportional increases in rFIXFc activity and Ag exposure were observed. With baseline subtraction, mean activity terminal t1/2 and mean residence time for rFIXFc were 56.7 and 71.8 hours, respectively. This is ∼ 3-fold longer than that reported for current rFIX products. The incremental recovery of rFIXFc was 0.93 IU/dL per IU/kg, similar to plasma-derived FIX. These results show that rFIXFc may offer a viable therapeutic approach to achieve prolonged hemostatic protection and less frequent dosing in patients with hemophilia B. The trial was registered at www.clinicaltrials.gov as NCT00716716. PMID:22110246

  6. Multicentre, randomized, open-label study of on-demand treatment with two prophylaxis regimens of recombinant coagulation factor IX in haemophilia B subjects.

    PubMed

    Valentino, L A; Rusen, L; Elezovic, I; Smith, L M; Korth-Bradley, J M; Rendo, P

    2014-05-01

    Few randomized studies have reported on the use of factor IX (FIX) for secondary prophylaxis in haemophilia B patients. This study aimed to evaluate the efficacy and safety of two secondary prophylaxis regimens of recombinant coagulation FIX, nonacog alfa, compared with on-demand therapy. Male subjects aged 6-65 years with severe or moderately severe haemophilia B (FIX:C ≤ 2, n = 50) and ≥12 bleeding episodes (including ≥6 haemarthroses episodes) within 12 months of study participation were enrolled in this multicentre, randomized, open-label, four-period crossover trial. The primary measure was the annualized bleeding rate (ABR) of two prophylactic regimens vs. on-demand therapy. In the intent-to-treat group, mean ABR values were 35.1, 2.6 and 4.6 for the first on-demand period, the 50 IU kg(-1) twice-weekly period, and the 100 IU kg(-1) once-weekly period respectively. Differences in ABR between the first on-demand period and both prophylaxis regimens were significant (P < 0.0001); no significant differences were observed between prophylaxis regimens (P = 0.22). Seven serious adverse events occurred in five subjects, none related to study drug. Results demonstrated that secondary prophylaxis therapy with nonacog alfa 50 IU kg(-1) twice weekly or 100 IU kg(-1) once weekly reduced ABR by 89.4% relative to on-demand treatment. Both prophylaxis regimens demonstrated favourable safety profiles in subjects with haemophilia B.

  7. [Determination of trace impurities in high purity titanium dioxide by high resolution inductively coupled plasma mass spectrometry].

    PubMed

    He, Xiao-Mei; Xie, Hua-Lin; Nie, Xi-Du; Tang, You-Gen

    2007-06-01

    An analytical method using high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) for the rapid simultaneous determination of twenty six elements (Be, Na, Mg, Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Mo, Cd, Sn, Sb, Ba, Ce, Nd, Sm, Pt, Pb and Bi) in high purity titanium dioxide was described. Samples were decomposed by (NH4)2SO4 and H2SO4. Most of the spectral interferences could be avoided by measuring in the high-resolution mode. The matrix effects due to the presence of excess sulfuric acid and Ti were evaluated. The optimum conditions for the determination were tested and discussed. The standard addition method was employed for quantitative analysis. The detection limits are 0.004-0.63 microg x g(-1), the recovery ratio is 87.6%-106.4%, and the RSD is less than 3.5%. The method is accurate, quick and convenient. It has been applied to the determination of trace impurities in high purity titanium dioxide with satisfactory results.

  8. High purity recombinant human Growth Hormone (rhGH) expression in Escherichia coli under phoA promoter.

    PubMed

    Song, Hao; Jiang, Jingxin; Wang, Xuedong; Zhang, Jianguo

    2016-07-26

    ABSTACT Recombinant human Growth Hormone (rhGH) is an important protein for human growth and is in high demand in clinics. Hence, it is necessary to develop an efficient fermentation process to produce highly pure rhGH. In this study, rhGH was expressed in Escherichia coli under alkaline phosphatase (phoA) promoter. The cultivation conditions for high expression level and purity of rhGH were investigated. The best initial phosphate concentration for rhGH expression, out of the 4 levels of initial phosphate concentration tests performed, was 12.6 mmol/L. Subsequently, 2 fed-batch cultivations under low dissolved oxygen (DO) (0% - 10%) and high DO (20% - 30%) conditions were carried out. High purity rhGH (92%) was obtained from 20% - 30% DO-stat cultivation, although the biomass did not show any significant difference. In summary, this research provided an efficient fermentation process for high purity rhGH production from E. coli under phoA promoter, which can lower the production and purification costs for large-scale production of rhGH.

  9. Determination of trace elements in high purity alumina powder by helium enhanced direct current glow discharge mass spectrometry

    NASA Astrophysics Data System (ADS)

    Jung, Sehoon; Kim, Sunhye; Hinrichs, Joachim

    2016-08-01

    Trace impurities in high purity alumina powder were determined by fast flow direct current glow discharge mass spectrometry (GD-MS). The non-conductive samples were prepared with high purity graphite powder and used as a sample binder and as a secondary cathode. To improve the sensitivity of the GD-MS analysis, helium was introduced as an additional glow discharge gas to argon plasma. The quantification results of the GD-MS measurement were calculated by external calibration with matrix matched certified reference materials. The GD-MS results for the determination of Na, Mg, Si, Ca, Ti, V, Cr, Fe, Cu, Zn and Ga in the alumina samples agreed well with the certified values of a reference material and the results of chemical analysis using wet sample digestion with inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS). The GD-MS analysis is a rapid analysis technique to determine trace elements in non-conductive alumina to below mg·kg- 1 levels.

  10. Qualification and initial characterization of a high-purity 233U spike for use in uranium analyses

    SciTech Connect

    Mathew, K. J.; Canaan, R. D.; Hexel, C.; Giaquinto, J.; Krichinsky, A. M.

    2015-08-20

    Several high-purity 233U items potentially useful as isotope dilution mass spectrometry standards for safeguards, non-proliferation, and nuclear forensics measurements are identified and rescued from downblending. By preserving the supply of 233U materials of different pedigree for use as source materials for certified reference materials (CRMs), it is ensured that the safeguards community has high quality uranium isotopic standards required for calibration of the analytical instruments. One of the items identified as a source material for a high-purity CRM is characterized for the uranium isotope-amount ratios using thermal ionization mass spectrometry (TIMS). Additional verification measurements on this material using quadrupole inductively coupled plasma mass spectrometry (ICPMS) are also performed. As a result, the comparison of the ICPMS uranium isotope-amount ratios with the TIMS data, with much smaller uncertainties, validated the ICPMS measurement practices. ICPMS is proposed for the initial screening of the purity of items in the rescue campaign.

  11. Tensile properties and interfacial bonding of multi-layered, high-purity titanium strips fabricated by ARB process.

    PubMed

    Ghafari-Gousheh, Soroush; Nedjad, Syamak Hossein; Khalil-Allafi, Jafar

    2015-11-01

    Severe plastic deformation (SPD) processing has shown very effective in promotion of mechanical properties of metals and alloys. In this study, the results of investigating mechanical properties and also inter-layer bond performance of accumulative roll bonded high purity titanium (HP-Ti) strips are presented. High purity titanium plates were severely deformed by use of a combination of cold rolling (CR) to a thickness reduction of approximately 87% and then accumulative roll bonding (ARB) for three cycles (N=3) at ambient temperature. Optical and scanning electron microscopy, tensile testing, and hardness measurements were conducted. The ARB strips exhibited lower tensile strength and ductility in comparison to cold rolled one which can basically be attributed to the poor function of the latest bonds established in the centerlines of the strips. Fractographic examinations revealed the interfacial de-bonding along the centerline between the layers having undergone roll bonding for just one cycle. It was while the interfaces having experienced roll bonding for more cycles showed much higher resistance against delaminating.

  12. Qualification and initial characterization of a high-purity 233U spike for use in uranium analyses

    DOE PAGES

    Mathew, K. J.; Canaan, R. D.; Hexel, C.; ...

    2015-08-20

    Several high-purity 233U items potentially useful as isotope dilution mass spectrometry standards for safeguards, non-proliferation, and nuclear forensics measurements are identified and rescued from downblending. By preserving the supply of 233U materials of different pedigree for use as source materials for certified reference materials (CRMs), it is ensured that the safeguards community has high quality uranium isotopic standards required for calibration of the analytical instruments. One of the items identified as a source material for a high-purity CRM is characterized for the uranium isotope-amount ratios using thermal ionization mass spectrometry (TIMS). Additional verification measurements on this material using quadrupole inductivelymore » coupled plasma mass spectrometry (ICPMS) are also performed. As a result, the comparison of the ICPMS uranium isotope-amount ratios with the TIMS data, with much smaller uncertainties, validated the ICPMS measurement practices. ICPMS is proposed for the initial screening of the purity of items in the rescue campaign.« less

  13. Matrix Elimination Ion Chromatography Method for the Determination of Trace Levels of Anionic Impurities in High Purity Cesium Iodide

    PubMed Central

    Ayushi; Kumar, Sangita D.; Reddy, A.V.R.

    2012-01-01

    In the present study an ion chromatographic method based on matrix elimination has been developed for the determination of anionic impurities in high purity cesium iodide crystals. The presence of impurities has a detrimental effect on the characteristics of detectors based on cesium iodide crystals. In particular, oxygen-containing anions inhibit the resolving power of scintillators and decrease the optical absorption. The quantitative determination of anions (fluoride, chloride, bromide, nitrate, phosphate, and sulphate) simultaneously in the high-purity cesium iodide crystals has not been carried out before. The large concentration of iodide poses a challenge in the determination of anions (especially phosphate and sulphate); hence, matrix elimination is accomplished by adopting a sample pretreatment technique. The method is validated for linearity, accuracy, and precision. The limit of detection for different anions is in the range of 0.3–3 µg/g, and the relative standard deviation is in the range of 4–6% for the overall method. PMID:22291061

  14. Comparative field study: impact of laboratory assay variability on the assessment of recombinant factor IX Fc fusion protein (rFIXFc) activity.

    PubMed

    Sommer, Jurg M; Buyue, Yang; Bardan, Sara; Peters, Robert T; Jiang, Haiyan; Kamphaus, George D; Gray, Elaine; Pierce, Glenn F

    2014-11-01

    Due to variability in the one-stage clotting assay, the performance of new factor IX (FIX) products should be assessed in this assay. The objective of this field study was to evaluate the accuracy of measuring recombinant FIX Fc fusion protein (rFIXFc) activity in clinical haemostasis laboratories using the one-stage clotting assay. Human haemophilic donor plasma was spiked with rFIXFc or BeneFIX® at 0.80, 0.20, or 0.05 IU/ml based on label potency. Laboratories tested blinded samples using their routine one-stage assay and in-house FIX plasma standard. The mean spike recoveries for BeneFIX (n=30 laboratories) were 121 %, 144 %, and 168 % of expected at nominal 0.80, 0.20, and 0.05 IU/ml concentrations, respectively. Corresponding rFIXFc spike recoveries were 88 %, 107 %, and 132 % of expected, respectively. All BeneFIX concentrations were consistently overestimated by most laboratories. rFIXFc activity was reagent-dependent; ellagic acid and silica gave higher values than kaolin, which underestimated rFIXFc. BeneFIX demonstrated significantly reduced chromogenic assay activity relative to one-stage assay results and nominal activity, while rFIXFc activity was close to nominal activity at three concentrations with better dilution linearity than the typical one-stage assay. In conclusion, laboratory- and reagent-specific assay variabilities were revealed, with progressively higher variability at lower FIX concentrations. Non-parallelism against the FIX plasma standard was observed in all one-stage assays with rFIXFc and BeneFIX, leading to significant overestimation of FIX activity at lower levels and generally high inter-laboratory variability. Compared to the accuracy currently achieved in clinical laboratories when measuring other rFIX products, most laboratories measured rFIXFc activity with acceptable accuracy and reliability using routine one-stage assay methods and commercially available plasma standards.

  15. An Exon-Specific U1snRNA Induces a Robust Factor IX Activity in Mice Expressing Multiple Human FIX Splicing Mutants

    PubMed Central

    Balestra, Dario; Scalet, Daniela; Pagani, Franco; Rogalska, Malgorzata Ewa; Mari, Rosella; Bernardi, Francesco; Pinotti, Mirko

    2016-01-01

    In cellular models we have demonstrated that a unique U1snRNA targeting an intronic region downstream of a defective exon (Exon-specific U1snRNA, ExSpeU1) can rescue multiple exon-skipping mutations, a relevant cause of genetic disease. Here, we explored in mice the ExSpeU1 U1fix9 toward two model Hemophilia B-causing mutations at the 5′ (c.519A > G) or 3′ (c.392-8T > G) splice sites of F9 exon 5. Hydrodynamic injection of wt-BALB/C mice with plasmids expressing the wt and mutant (hFIX-2G5′ss and hFIX-8G3′ss) splicing-competent human factor IX (hFIX) cassettes resulted in the expression of hFIX transcripts lacking exon 5 in liver, and in low plasma levels of inactive hFIX. Coinjection of U1fix9, but not of U1wt, restored exon inclusion of variants and in the intrinsically weak FIXwt context. This resulted in appreciable circulating hFIX levels (mean ± SD; hFIX-2G5′ss, 1.0 ± 0.5 µg/ml; hFIX-8G3′ss, 1.2 ± 0.3 µg/ml; and hFIXwt, 1.9 ± 0.6 µg/ml), leading to a striking shortening (from ~100 seconds of untreated mice to ~80 seconds) of FIX-dependent coagulation times, indicating a hFIX with normal specific activity. This is the first proof-of-concept in vivo that a unique ExSpeU1 can efficiently rescue gene expression impaired by distinct exon-skipping variants, which extends the applicability of ExSpeU1s to panels of mutations and thus cohort of patients. PMID:27701399

  16. Role of Chemical Driving Force in Martensitic Transformations of High-Purity Fe-Cr-Ni Alloys

    NASA Astrophysics Data System (ADS)

    Behjati, P.; Najafizadeh, A.

    2011-12-01

    The main objective of the present work is to point out the respective roles of chemical driving force and stacking fault energy (SFE) in the occurrence of martensitic transformations in high-purity Fe-Cr-Ni alloys. For this purpose, the transmission electron microscope (TEM), X-ray diffractometer, thermal differential microanalyzer (TDA), and tension test were employed to report M s temperatures, austenite stacking fault energies, and driving forces for the concerned alloys. It was observed that the martensitic transformations in the studied alloys occur through the γ → ɛ → α' steps. As a remarkable result, it was shown that a low SFE, if necessary to ɛ-phase nucleation, is not a sufficient condition for nucleation of α' phase. In fact, the formation of stable α' nuclei from α' embryos occur if the required chemical driving force is provided. Also, an equation was proposed for the kinetics of spontaneous martensitic transformation as a function of driving force.

  17. Large-scale fabrication of boron nitride nanotubes with high purity via solid-state reaction method

    PubMed Central

    2014-01-01

    An effective solid-state reaction method is reported for synthesizing boron nitride nanotubes (BNNTs) in large scale and with high purity by annealing amorphous boron powder and ferric chloride (FeCl3) catalyst in ammonia atmosphere at elevated temperatures. FeCl3 that has rarely been utilized before is introduced not only as a catalyst but also as an efficient transforming agent which converts boron powder into boron chloride (BCl3) vapor in situ. The nanotubes are bamboo in shape and have an average diameter of about 90 nm. The effect of synthetic temperatures on nanotube morphology and yield is investigated. The photoluminescence (PL) measurement shows emission bands of the nanotubes at 354, 423, 467, and 666 nm. A combined growth mechanism of vapor–liquid-solid (VLS) and solid–liquid-solid (SLS) model is proposed for the formation of the BNNTs. PMID:25313303

  18. Engineering of high purity ultra-long optical needle field through reversing the electric dipole array radiation.

    PubMed

    Wang, Jiming; Chen, Weibin; Zhan, Qiwen

    2010-10-11

    We report a new method to create high purity longitudinally polarized field with extremely long depth of focus in the focal volume of a high numerical aperture (NA) objective lens. Through reversing the radiated field from an electric dipole array situated near the focus of the high-NA lens, the required incident field distribution in the pupil plane for the creation of an ultra-long optical needle field can be found. Numerical examples demonstrate that an optical needle field with a depth of focus up to 8λ is obtainable. Throughout the depth of focus, this engineered focal field maintains a diffraction limited transverse spot size (<0.43λ) with high longitudinal polarization purity. From the calculated pupil plane distribution, a simplified discrete complex pupil filter can be designed and significant improvements over the previously reported complex filters are clearly demonstrated.

  19. Industrial-scale separation of high-purity single-chirality single-wall carbon nanotubes for biological imaging.

    PubMed

    Yomogida, Yohei; Tanaka, Takeshi; Zhang, Minfang; Yudasaka, Masako; Wei, Xiaojun; Kataura, Hiromichi

    2016-06-28

    Single-chirality, single-wall carbon nanotubes are desired due to their inherent physical properties and performance characteristics. Here, we demonstrate a chromatographic separation method based on a newly discovered chirality-selective affinity between carbon nanotubes and a gel containing a mixture of the surfactants. In this system, two different selectivities are found: chiral-angle selectivity and diameter selectivity. Since the chirality of nanotubes is determined by the chiral angle and diameter, combining these independent selectivities leads to high-resolution single-chirality separation with milligram-scale throughput and high purity. Furthermore, we present efficient vascular imaging of mice using separated single-chirality (9,4) nanotubes. Due to efficient absorption and emission, blood vessels can be recognized even with the use of ∼100-fold lower injected dose than the reported value for pristine nanotubes. Thus, 1 day of separation provides material for up to 15,000 imaging experiments, which is acceptable for industrial use.

  20. Purification of Al(OH)3 synthesized by Bayer process for preparation of high purity alumina as sapphire raw material

    NASA Astrophysics Data System (ADS)

    Park, No-Kuk; Choi, Hee-Young; Kim, Do-Hyeong; Lee, Tae Jin; Kang, Misook; Lee, Won Gun; Kim, Heun Duk; Park, Joon Woo

    2013-06-01

    To produce high purity alumina as the raw material for sapphire growth, gibbsite, which is the precursor for the synthesis of alumina, was synthesized by the Bayer process, and treated with an acid solution to remove the sodium component. In this study, the digestion process was carried out under the following conditions: an Al/Na ratio of 0.9 with a 5 N NaOH solution and a temperature of 140 °C. Bauxite containing 75 wt% alumina was converted to a sodium aluminate solution, and 60 wt% of the dissolved aluminate was crystallized to gibbsite. The sodium content in the gibbsite, which was measured by inductively coupled plasma/optical emission spectroscopy, was reduced by approximately 5700 ppm and below 2900 ppm after the water washing and acid treatments, respectively. The sodium content decreased with increasing acid concentration in the solution, temperature and acid treatment time.

  1. Delta-Doped High Purity Silicon UV-NIR CCDs with High QE and Low Dark Current

    NASA Technical Reports Server (NTRS)

    Hoenk, Michael; Blacksberg, Jordana; Nikzad, Shouleh; Elliott, S. Tom; Holland, Steve; Bebek, Chris; Scowen, Paul; Veach, Todd

    2006-01-01

    Delta doping process was developed on p-channel CCDs for MIDEX-Orion and JDEM/SNAP and was applied to large format (2k x4k) CCDs. Delta doping is applied to fully-fabricated CCDs (complete with Al metallization). High QE and low dark current is demonstrated with delta doped p-channel CCDs. In-house AR coating is demonstrated. Advantages include: Delta doping enables high QE and stability across the entire spectral range attainable with silicon. Delta doping is a low temperature process and is compatible with fully-fabricated detector arrays. Same base device for Orion two channels. High radiation tolerance and no thinning requirements of high purity p-channel. CCDs are additional advantages.

  2. The use of a high-purity germanium detector for routine measurements of {sup 125}I in radiation workers

    SciTech Connect

    Kopp, P.; Bergmann, H.; Havlik, E.; Aiginger, H.; Unfried, E.; Riedlmayer, L.

    1994-12-01

    A high-purity germanium detector was calibrated for the assessment of {sup 125}I uptake in the thyroid gland of radiation workers. A cylindrical water phantom (perspex walls) with high flexibility for position and size of the thyroid was constructed. Within a massive shielding chamber built for a whole-body counter, an activity of 2.2 Bq was detectable (MDA). This is well below the very restrictive limiting value of 20 Bq for inhalation specified by Austrian law. An activity of 128 Bq was measured with a statistical uncertainty of 5% in a counting period of 10 min. Various parameters influencing the result are investigated as well as the performance of two other measurement geometries outside the shielding chamber. 13 refs., 4 figs., 2 tabs.

  3. Microfluidic Pipette Tip for High-Purity and High-Throughput Blood Plasma Separation from Whole Blood.

    PubMed

    Kim, Byeongyeon; Oh, Sein; You, Dongwon; Choi, Sungyoung

    2017-02-07

    Blood plasma separation from whole blood is often limited by numerous blood cells which can compromise separation processes and thus deteriorate separation performance such as purity and throughput. To address this challenge, we present a microfluidic pipet tip composed of slant array ridges that enable autonomous blood cell focusing without significant deviation as well as facilitating a high degree of parallelization without compromising separation purity. With these advantages, we achieved high-purity (99.88%) and high-throughput (904.3 μL min(-1)) plasma separation from whole blood. In combination with a smart pipet, we successfully demonstrated rapid, inexpensive, and equipment-free blood plasma preparation for pretransfusion testing.

  4. Industrial-scale separation of high-purity single-chirality single-wall carbon nanotubes for biological imaging

    NASA Astrophysics Data System (ADS)

    Yomogida, Yohei; Tanaka, Takeshi; Zhang, Minfang; Yudasaka, Masako; Wei, Xiaojun; Kataura, Hiromichi

    2016-06-01

    Single-chirality, single-wall carbon nanotubes are desired due to their inherent physical properties and performance characteristics. Here, we demonstrate a chromatographic separation method based on a newly discovered chirality-selective affinity between carbon nanotubes and a gel containing a mixture of the surfactants. In this system, two different selectivities are found: chiral-angle selectivity and diameter selectivity. Since the chirality of nanotubes is determined by the chiral angle and diameter, combining these independent selectivities leads to high-resolution single-chirality separation with milligram-scale throughput and high purity. Furthermore, we present efficient vascular imaging of mice using separated single-chirality (9,4) nanotubes. Due to efficient absorption and emission, blood vessels can be recognized even with the use of ~100-fold lower injected dose than the reported value for pristine nanotubes. Thus, 1 day of separation provides material for up to 15,000 imaging experiments, which is acceptable for industrial use.

  5. Formation and annihilation of intrinsic defects induced by electronic excitation in high-purity crystalline SiO{sub 2}

    SciTech Connect

    Kajihara, Koichi; Skuja, Linards; Hosono, Hideo

    2013-04-14

    Formation and thermal annihilation of intrinsic defects in {alpha}-quartz were examined using high-purity samples, while minimizing the contributions of reactions involving metallic impurities. Electronic excitation with {sup 60}Co {gamma}-rays was employed to avoid radiation-induced amorphization. The results clearly show that formation of oxygen vacancies (Si-Si bonds) as a result of decomposition of regular Si-O-Si bonds (Frenkel process) is the dominant intrinsic defect process. Compared with amorphous SiO{sub 2}, in {alpha}-quartz, the formation yield of Si-Si bonds is an order of magnitude smaller, the 7.6 eV optical absorption band is less broadened, and their thermal annihilation is complete at a lower temperature, around the {alpha}-{beta} quartz transition. In contrast, radiation-induced interstitial oxygen atoms practically do not form interstitial oxygen molecules.

  6. Enhanced quantum efficiency of high-purity silicon imaging detectors by ultralow temperature surface modification using Sb doping

    NASA Technical Reports Server (NTRS)

    Blacksberg, Jordana; Hoenk, Michael E.; Elliott, S. Tom; Holland, Stephen E.; Nikzad, Shouleh

    2005-01-01

    A low temperature process for Sb doping of silicon has been developed as a backsurface treatment for high-purity n-type imaging detectors. Molecular beam epitaxy (MBE) is used to achieve very high dopant incorporation in a thin, surface-confined layer. The growth temperature is kept below 450 (deg)C for compatibility with Al-metallized devices. Imaging with MBE-modified 1kx1k charge coupled devices (CCDs) operated in full depletion has been demonstrated. Dark current is comparable to the state-of-the-art process, which requires a high temperature step. Quantum efficiency is improved, especially in the UV, for thin doped layers placed closer to the backsurface. Near 100% internal quantum efficiency has been demonstrated in the ultraviolet for a CCD with a 1.5 nm silicon cap layer.

  7. A facile approach for synthesizing Fe-based layered double hydroxides with high purity and its exfoliation.

    PubMed

    Wang, Yinling; Li, Fajun; Dong, Shengye; Liu, Xiaowang; Li, Maoguo

    2016-04-01

    Transition metal (e.g., Fe, Co, Ni)-based layered double hydroxides (LDHs) and their exfoliated nanosheets have great potential applications due to their redox and magnetic properties. Here we report a facile approach for the preparation of Co-Fe LDHs with good crystallinity and high purity. The proposed approach includes two steps: (1) The mixed divalent metal (e.g., Co(2+), Fe(2+)) hydroxides were first synthesized using a homogeneous precipitation without piping N2 into the system; hexamethylenetetramine (HMT) was the hydrolysis agent providing OH(-), and hydroxylamine hydrochloride (HAH) was used as both a reducing and a complexing reagent. (2) Then the as-prepared hydroxides were slowly oxidated by air and simultaneously intercalated by CO3(2-) to form CO3-intercalated LDHs. The Co-Fe LDHs were roundly characterized by XRD, SEM, EDX and FT-IR. The effect of HAH on the morphology and structure of the Co-Fe LDHs was also studied. The magnetism of Co-Fe LDHs at room temperature was investigated and the results showed that the LDHs displayed a low saturation magnetization value of 6.3emug(-1), suggesting that the purity of the products was very high. In addition, the intercalated CO3(2-) in the Co-Fe LDHs could be successfully exchanged with other anions such as Cl(-) and ClO4(-). Furthermore, the exchanged-LDHs could be exfoliated in formamide. This work establishes a new method for the synthesis of Fe-based LDHs with good crystallinity and high purity under mild conditions, and can accelerate the development of applications using these layered materials.

  8. Measurement of the high-field Q-drop in a high-purity large-grain niobium cavity for different oxidation processes

    SciTech Connect

    Ciovati, Gianluigi; Kneisel, Peter; gurevich, alex

    2007-06-01

    The most challenging issue for understanding the performance of superconducting radio-frequency (rf) cavities made of high-purity (residual resistivity ratio > 200) niobium is due to a sharp degradation (“Q-drop”) of the cavity quality factor Q0(Bp) as the peak surface magnetic field (Bp) exceeds about 90 mT, in the absence of field emission. In addition, a low-temperature (100 – 140 C) “in-situ” baking of the cavity was found to be beneficial in reducing the Q-drop. In this contribution, we present the results from a series of rf tests at 1.7 K and 2.0 K on a single-cell cavity made of high-purity large (with area of the order of few cm2) grain niobium which underwent various oxidation processes, after initial buffered chemical polishing, such as anodization, baking in pure oxygen atmosphere and baking in air up to 180 °C, with the objective of clearly identifying the role of oxygen and the oxide layer on the Q-drop. During each rf test a temperature mapping system allows measuring the local temperature rise of the cavity outer surface due to rf losses, which gives information about the losses location, their field dependence and space distribution. The results confirmed that the depth affected by baking is about 20 – 30 nm from the surface and showed that the Q-drop did not re-appear in a previously baked cavity by further baking at 120 °C in pure oxygen atmosphere or in air up to 180 °C. These treatments increased the oxide thickness and oxygen concentration, measured on niobium samples which were processed with the cavity and were analyzed with Transmission Electron Microscope (TEM) and Secondary Ion Mass Spectroscopy (SIMS). Nevertheless, the performance of the cavity after air baking at 180 °C degraded significantly and the temperature maps showed high losses, uniformly distributed on the surface, which could be completely recovered only by a post-purification treatment at 1250 °C. A statistic of the position of the “hot-spots” on the

  9. Title IX: Boom or Bust?

    ERIC Educational Resources Information Center

    Mather, Marilyn J.

    2003-01-01

    Athletics has been significantly impacted by Title IX through an increase the number of female athletes, the number of teams available, and indirectly, the development of women's professional leagues. However, women in leadership positions in athletics have declined significantly since Title IX was signed into law. A concern about the…

  10. Purification of high-purity glycyrrhizin from licorice using hydrophilic interaction solid phase extraction coupled with preparative reversed-phase liquid chromatography.

    PubMed

    Yu, Wenyi; Jin, Hongli; Shen, Aijin; Deng, Liang; Shi, Jianlian; Xue, Xingya; Guo, Yadong; Liu, Yanfang; Liang, Xinmiao

    2017-01-01

    Glycyrrhizin (GA), a major bioactive compound in licorice, has been extensively used throughout the world as a medicine to treat chronic viral hepatitis and allergic dermatitis. In this study, a new method based on hydrophilic interaction solid phase extraction (HILIC-SPE) and preparative reversed-phase liquid chromatography (prep-RPLC) was developed to purify GA with high purity from the complex licorice extract. Via evaluation of retention behavior of GA and flavonoids in different commercially available columns, a hydrophilic column--Click XIon was finally chosen for the purification due to its excellent resolution toward GA and flavonoids under HILIC mode. To optimize the SPE elution conditions, relative factors including water content, pH and ionic strength had been investigated in chromatographic condition. The result indicated that the most appropriate water content was 30% and pH at 4.00, as well as salt concentration should be controlled at 5mM. In addition, the optimization revealed that GA experiences both hydrophilic interaction and ion-exchange interaction on the Click XIon material. According to the chromatographic evaluation, the optimized conditions were applied to HILIC-SPE to enrich GA from licorice, which leads to an increased content of GA from 13.67% to 64.22%. Finally, prep-RPLC was performed to obtain GA with purity higher than 99.00%,which demonstrating great prospect in large-scale preparation of GA.

  11. Characterization of carbonic anhydrase IX (CA IX) as an endogenous marker of chronic hypoxia in live human tumor cells

    SciTech Connect

    Vordermark, Dirk . E-mail: vordermark_d@klinik.uni-wuerzburg.de; Kaffer, Anja; Riedl, Susanne; Katzer, Astrid; Flentje, Michael

    2005-03-15

    Purpose: Published clinical studies provide conflicting data regarding the prognostic significance of carbonic anhydrase IX (CA IX) overexpression as an endogenous marker of tumor hypoxia and its comparability with other methods of hypoxia detection. We performed a systematic analysis of CA IX protein levels under various in vitro conditions of tumor hypoxia in HT 1080 human fibrosarcoma and FaDu human pharyngeal carcinoma cells. Because sorting of live CA IX positive cells from tumors provides a tool to study the radiosensitivity of chronically hypoxic cells, we modified and tested a CA IX flow cytometry protocol on mixed hypoxic/aerobic suspensions of HT 1080 and FaDu cells. Methods and materials: HT 1080 and FaDu cells were treated with up to 24 h of in vitro hypoxia and up to 96 h of reoxygenation. To test the effect of nonhypoxic stimuli, glucose and serum availability, pH and cell density were modified. CA IX protein was quantified in Western blots of whole-cell lysates. Mixed suspensions with known percentages of hypoxic cells were prepared for CA IX flow cytometry. The same mixtures were assayed for clonogenic survival after 10 Gy. Results: Hypoxia-induced CA IX protein expression was seen after >6 h at {<=}5% O{sub 2}, and protein was stable over 96 h of reoxygenation in both cell lines. Glucose deprivation abolished the hypoxic CA IX response, and high cell density caused CA IX induction under aerobic conditions. Measured percentages of CA IX-positive cells in mixtures closely reflected known percentages of hypoxic cells in HT 1080 and were associated with radioresistance of mixtures after 10 Gy. Conclusion: CA IX is a stable marker of current or previous chronic hypoxia but influenced by nonhypoxic stimuli. Except the time course of accumulation, all properties of this marker resembled our previous findings for hypoxia-inducible factor-1{alpha}. A modified flow cytometry protocol provided good separability of CA IX-negative and -positive cells in vitro

  12. Physical activity in individuals with haemophilia and experience with recombinant factor VIII Fc fusion protein and recombinant factor IX Fc fusion protein for the treatment of active patients: a literature review and case reports

    PubMed Central

    Wang, Michael; Álvarez-Román, María Teresa; Chowdary, Pratima; Quon, Doris V.; Schafer, Kim

    2016-01-01

    The World Federation of Hemophilia and the National Hemophilia Foundation encourage people with haemophilia (PWH) to participate in routine physical activity. The benefits of physical activity for PWH include improvements in joint, bone, and muscle health. Accordingly, a number of studies suggest that levels of physical activity among PWH are similar to those of their healthy peers, especially among individuals who began prophylaxis at an early age (≤3 years). Importantly, several studies found either no increased risk or only a transient increase in risk of bleeding with more intensive physical activity compared with less intensive physical activity. Data on optimal prophylaxis regimens for PWH who participate in physical/sporting activities; however, remain sparse. Long-acting recombinant factor VIII Fc fusion protein (rFVIIIFc) and recombinant factor IX Fc fusion protein (rFIXFc) demonstrated efficacy for the prevention and treatment of bleeding episodes in Phase 3 clinical trials of participants with haemophilia A and B, respectively, with most individuals able to maintain or increase their physical activities. This manuscript reviews the current literature that describes physical activity in PWH. Additionally, case studies are presented to provide supplemental information to clinicians illustrating the use of rFVIIIFc and rFIXFc in physically active patients with haemophilia A and B, respectively. These case reports demonstrate that it is possible for patients to be physically active and maintain good control of their haemophilia with extended interval prophylactic dosing using rFVIIIFc or rFIXFc. PMID:27116081

  13. Preparation of high purity crystalline silicon by electro-catalytic reduction of sodium hexafluorosilicate with sodium below 180 °C.

    PubMed

    Chen, Yuan; Liu, Yang; Wang, Xin; Li, Kai; Chen, Pu

    2014-01-01

    The growing field of silicon solar cells requires a substantial reduction in the cost of semiconductor grade silicon, which has been mainly produced by the rod-based Siemens method. Because silicon can react with almost all of the elements and form a number of alloys at high temperatures, it is highly desired to obtain high purity crystalline silicon at relatively low temperatures through low cost process. Here we report a fast, complete and inexpensive reduction method for converting sodium hexafluorosilicate into silicon at a relatively low reaction temperature (∼ 200 °C). This temperature could be further decreased to less than 180 °C in combination with an electrochemical approach. The residue sodium fluoride is dissolved away by pure water and hydrochloric acid solution in later purifying processes below 15 °C. High purity silicon in particle form can be obtained. The relative simplicity of this method might lead to a low cost process in producing high purity silicon.

  14. Effect of low-temperature (77 K) quasihydrostatic extrusion on the properties of high-purity titanium: The role of initial structural state

    NASA Astrophysics Data System (ADS)

    Tikhonovsky, M. A.; Khaimovich, P. A.; Kutniy, K. V.; Kislyak, I. F.; Okovit, V. S.; Rudycheva, T. Yu.

    2013-11-01

    This is a study of the effect of quasihydrostatic extrusion at liquid nitrogen and room temperatures on the evolution of the structure and mechanical properties of high-purity titanium produced by severe plastic deformation in a swaging-extrusion-drawing regime and with subsequent annealing at temperatures of 350-550 °C. It is shown that a combination of severe plastic deformation and cryogenic quasihydrostatic extrusion makes it possible to create high-purity nanocrystalline titanium with high strength and plasticity.

  15. The formation of high-purity isocyanurate through proazaphosphatrane-catalysed isocyanate cyclo-trimerisation: computational insights.

    PubMed

    Gibb, Jack N; Goodman, Jonathan M

    2013-01-07

    Polyurethane foams are widely used materials and control of their physical properties is a significant challenge. Management of cyclo-trimerisation during the polymerisation process is vital when tailoring the mechanical properties of the foam. Proazaphosphatranes are known to efficiently catalyse the cyclo-trimerisation of organic isocyanates, giving high purity isocyanurate with little uretdione by-product. The mechanism of this catalysis was previously unknown, although some zwitterionic intermediates have been identified spectroscopically. We have investigated a nucleophilic-catalysis reaction pathway involving sequential addition of methyl isocyanate to activated zwitterionic intermediates using density functional theory calculations. Evidence for significant transannulation by the proazaphosphatrane nitrogen was found for all intermediates, offering stabilisation of the phosphonium cation. Steric crowding at the proazaphosphatrane nucleophilic phosphorus gives rise to a preference for direct isocyanurate formation rather than via the uretdione, in sharp contrast to the uncatalysed system which has been found to preferentially proceed via the kinetic uretdione product. The investigations suggest the mechanism of proazaphosphatrane catalysed cyclo-oligomerisation does not proceed via the uretdione product, and hence why little of this impurity is observed experimentally.

  16. Influence of Grain Boundaries and their Composition on the Deformation Strength of High-purity, Synthetic Forsterite

    NASA Astrophysics Data System (ADS)

    Dillman, Amanda Marie

    Grain boundaries are an important feature of the mantle. With recent studies suggesting the majority of the upper mantle deforms by grain boundary sliding (Hirth and Kohlstedt, 2003; Hansen et al., 2013), understanding the role grain boundaries play is key. As grain boundary sliding always requires an accommodation mechanism, directly determining the contribution of grain boundary sliding to total strain on a sample is important for modeling deformation in the mantle. Altering grain boundary composition can change the structure and viscosity of the boundary. Understanding the effects of grain boundary composition is necessary for comparing data sets of different olivine as well as for accurately extrapolating experimental data to represent the mantle. In Chapter 2, uniaxial deformation experiments on high-purity synthetic forsterite at high temperature and ambient pressure are used to characterize the contribution of grain boundary sliding to strain in diffusion creep. Experiments were conducted in a one-atmosphere deformation rig, which allowed the polished surfaces of the samples to be analyzed with atomic force microscopy. The high temperature necessary for deformation enabled a great deal of thermal grooving, which can dramatically alter the topography of an initially polished surface. A methodology was developed to correct for the effect of thermal grooving and determine the amount of grain boundary sliding as a function of grain size and stress. A comparison is also made between two popular methods for determining grain size: the line intercept method and the equivalent area circle method. The line intercept method consistently produces larger grain sizes than the equivalent area circle method. In Chapter 3, triaxial compression experiments on forsterite are used to determine the effect of grain boundary chemistry on deformation strength. High-purity synthetic forsterite was doped with either Ca or Pr and then deformed at high temperature and a confining

  17. CO{sub 2} looping cycle performance of a high-purity limestone after thermal activation/doping

    SciTech Connect

    Vasilije Manovic; Edward J. Anthony; Gemma Grasa; J. Carlos Abanades

    2008-09-15

    The influence of thermal pretreatment on the performance of a high-purity limestone (La Blanca) during CO{sub 2} capture cycles is investigated in this paper. This limestone was chosen for more detailed investigation because, in earlier research, it failed to show any favorable effect as a result of thermal pretreatment. Here, the original sample, with a particle size of 0.4-0.6 mm, and ground samples were thermally pretreated at 1000-1200{sup o}C, for 6-24 h, and then subjected to several carbonation/calcination cycles in a thermogravimetric analyzer (TGA). This work shows that thermal pretreatment failed to produce a significant self-reactivation effect during CO{sub 2} cycles, despite the use of a wide range of conditions during pretreatment (grinding, temperature, and pretreatment duration) as well as during cycling (CO{sub 2} concentration and duration of the carbonation stage). Additional doping experiments showed that both high Na content and lack of Al in La Blanca limestone cause poor self-reactivation performance after thermal pretreatment. Scanning electron microscope-energy-dispersive X-ray (SEM-EDX) analyses also confirmed more pronounced sintering and loss of activity, which we believe are caused by the relatively high Na content. However, stabilization of sorbent particle morphology by Al can allow this limestone to show self-reactivation performance and higher conversions over a longer series of CO{sub 2} cycles. 35 refs., 12 figs., 2 tabs.

  18. A simple dissolved metals mixing method to produce high-purity MgTiO{sub 3} nanocrystals

    SciTech Connect

    Pratapa, Suminar E-mail: suminar-pratapa@physics.its.ac.id; Baqiya, Malik A. E-mail: suminar-pratapa@physics.its.ac.id; Istianah, E-mail: suminar-pratapa@physics.its.ac.id; Lestari, Rina E-mail: suminar-pratapa@physics.its.ac.id; Angela, Riyan E-mail: suminar-pratapa@physics.its.ac.id

    2014-02-24

    A simple dissolved metals mixing method has been effectively used to produce high-purity MgTiO{sub 3} (MT) nanocrystals. The method involves the mixing of independently dissolved magnesium and titanium metal powders in hydrochloric acid followed by calcination. The phase purity and nanocrystallinity were determined by making use of laboratory x-ray diffraction data, to which Rietveld-based analyses were performed. Results showed that the method yielded only one type magnesium titanate powders, i.e. MgTiO{sub 3}, with no Mg{sub 2}TiO{sub 4} or MgTi{sub 2}O{sub 5} phases. The presence of residual rutile or periclase was controlled by adding excessive Mg up to 5% (mol) in the stoichiometric mixing. The method also resulted in MT nanocrystals with estimated average crystallite size of 76±2 nm after calcination at 600°C and 150±4 nm (at 800°C). A transmission electron micrograph confirmed the formation of the nanocrystallites.

  19. Purity analyses of high-purity organic compounds with nitroxyl radicals based on the Curie–Weiss law

    SciTech Connect

    Matsumoto, Nobuhiro Shimosaka, Takuya

    2015-05-07

    This work reports an attempt to quantify the purities of powders of high-purity organic compounds with stable nitroxyl radicals (namely, 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO), 1-oxyl-2,2,6,6-tetramethyl-4-hydroxypiperidine (TEMPOL), and 4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl benzoate (4-hydroxy-TEMPO benzoate)) in terms of mass fractions by using our “effective magnetic moment method,” which is based on both the Curie–Weiss law and a fundamental equation of electron paramagnetic resonance (ESR). The temperature dependence of the magnetic moment resulting from the radicals was measured with a superconducting quantum interference device magnetometer. The g value for each compound was measured with an X-band ESR spectrometer. The results of the purities were (0.998 ± 0.064) kg kg{sup −1} for TEMPO, (1.019 ± 0.040) kg kg{sup −1} for TEMPOL, and (1.001 ± 0.048) kg kg{sup −1} for 4-hydroxy-TEMPO benzoate. These results demonstrate that this analytical method as a future candidate of potential primary direct method can measure the purities with expanded uncertainties of approximately 5%.

  20. Plastic deformation of high-purity a-titanium: model development and validation using the Taylor cylinder impact test

    NASA Astrophysics Data System (ADS)

    Chandola, Nitin; Revil-Baudard, Benoit; Cazacu, Oana

    2016-08-01

    Results of an experimental study on the quasi-static and high-rate plastic deformation due to impact of a high-purity, polycrystalline, a-titanium material are presented. To quantify the plastic anisotropy and tension-compression asymmetry of the material, first monotonic uniaxial compression and tension tests were carried out at room temperature under quasi-static conditions. It was found that the material is transversely isotropic and displays strong strength differential effects. To characterize the material's strain rate sensitivity, Split Hopkinson Pressure Bar tests in tension and compression were also conducted. Taylor impact tests were performed for impact velocity of 196 m/s. Plastic deformation extended to 64% of the length of the deformed specimen, with little radial spreading. To model simultaneously the observed anisotropy, strain-rate sensitivity, and tension-compression asymmetry of the material, a three-dimensional constitutive model was developed. Key in the formulation is a macroscopic yield function [1] that incorporates the specificities of the plastic flow, namely the combined effects of anisotropy and tension-compression asymmetry. Comparison between model predictions and data show the capabilities of the model to describe with accuracy the plastic behavior of the a-Ti material for both quasi-static and dynamic loadings, in particular, a very good agreement was obtained between the simulated and experimental post-test Taylor specimen geometries.

  1. Industrial-scale separation of high-purity single-chirality single-wall carbon nanotubes for biological imaging

    PubMed Central

    Yomogida, Yohei; Tanaka, Takeshi; Zhang, Minfang; Yudasaka, Masako; Wei, Xiaojun; Kataura, Hiromichi

    2016-01-01

    Single-chirality, single-wall carbon nanotubes are desired due to their inherent physical properties and performance characteristics. Here, we demonstrate a chromatographic separation method based on a newly discovered chirality-selective affinity between carbon nanotubes and a gel containing a mixture of the surfactants. In this system, two different selectivities are found: chiral-angle selectivity and diameter selectivity. Since the chirality of nanotubes is determined by the chiral angle and diameter, combining these independent selectivities leads to high-resolution single-chirality separation with milligram-scale throughput and high purity. Furthermore, we present efficient vascular imaging of mice using separated single-chirality (9,4) nanotubes. Due to efficient absorption and emission, blood vessels can be recognized even with the use of ∼100-fold lower injected dose than the reported value for pristine nanotubes. Thus, 1 day of separation provides material for up to 15,000 imaging experiments, which is acceptable for industrial use. PMID:27350127

  2. Determination of indium in high purity antimony by electrothermal atomic absorption spectrometry (ETAAS) using boric acid as a modifier.

    PubMed

    Dash, K; Thangavel, S; Chaurasia, S C; Arunachalam, J

    2006-10-15

    The use of boric acid as a modifier for the determination of trace amount of indium in high purity antimony by electrothermal atomic absorption is described. It was found that the negative influence of the hydrofluoric acid, used for the digestion could not be eliminated by using stabilized temperature platform furnace (STPF) alone. Due to the high dissociation energy (D(0)=506kJmol(-1)) of indium fluoride, it is difficult to dissociate in the gas phase and hence is lost. In presence of HF (used for the dissolution of antimony), the universal Pd-Mg modifier does not work satisfactorily. Additionally, rising corrosion and reduced tube lifetime were observed when the acid digested (HF-HNO(3)) antimony solution was injected in to the platform. Improvement in platform life and elimination of interferences were achieved by the addition of boric acid as a chemical modifier together with ruthenium coating of the platform. Corrosive changes of the transversely heated graphite atomizer (THGA) platform surface were examined by scanning electron microscopy. The standard addition method was applied. A characteristic mass of 36pg was obtained. The detection limit of the proposed method is around 0.04mugg(-1). The developed method was applied to the determination of indium in real samples. The data obtained by this method were in good agreement with those obtained by ICP-MS.

  3. Towards a single step process to create high purity gold structures by electron beam induced deposition at room temperature

    NASA Astrophysics Data System (ADS)

    Mansilla, C.; Mehendale, S.; Mulders, J. J. L.; Trompenaars, P. H. F.

    2016-10-01

    Highly pure metallic structures can be deposited by electron beam induced deposition and they have many important applications in different fields. The organo-metallic precursor is decomposed and deposited under the electron beam, and typically it is purified with post-irradiation in presence of O2. However, this approach limits the purification to the surface of the deposit. Therefore, ‘in situ’ purification during deposition using simultaneous flows of both O2 and precursor in parallel with two gas injector needles has been tested and verified. To simplify the practical arrangements, a special concentric nozzle has been designed allowing deposition and purification performed together in a single step. With this new device metallic structures with high purity can be obtained more easily, while there is no limit on the height of the structures within a practical time frame. In this work, we summarize the first results obtained for ‘in situ’ Au purification using this concentric nozzle, which is described in more detail, including flow simulations. The operational parameter space is explored in order to optimize the shape as well as the purity of the deposits, which are evaluated through scanning electron microscope and energy dispersive x-ray spectroscopy measurements, respectively. The observed variations are interpreted in relation to other variables, such as the deposition yield. The resistivity of purified lines is also measured, and the influence of additional post treatments as a last purification step is studied.

  4. Development of High-purity Certified Reference Materials for 17 Proteinogenic Amino Acids by Traceable Titration Methods.

    PubMed

    Kato, Megumi; Yamazaki, Taichi; Kato, Hisashi; Eyama, Sakae; Goto, Mari; Yoshioka, Mariko; Takatsu, Akiko

    2015-01-01

    To ensure the reliability of amino acid analyses, the National Metrology Institute of Japan of the National Institute of Advanced Industrial Science and Technology (NMIJ/AIST) has developed high-purity certified reference materials (CRMs) for 17 proteinogenic amino acids. These CRMs are intended for use as primary reference materials to enable the traceable quantification of amino acids. The purity of the present CRMs was determined based on two traceable methods: nonaqueous acidimetric titration and nitrogen determination by the Kjeldahl method. Since neither method could distinguish compounds with similar structures, such as amino acid-related impurities, impurities were thoroughly quantified by combining several HPLC methods, and subtracted from the obtained purity of each method. The property value of each amino acid was calculated as a weighted mean of the corrected purities by the two methods. The uncertainty of the property value was obtained by combining measurement uncertainties of the two methods, a difference between the two methods, the uncertainty from the contribution of impurities, and the uncertainty derived from inhomogeneity. The uncertainty derived from instability was considered to be negligible based on stability monitoring of some CRMs. The certified value of each amino acid, property value with uncertainty, was given for both with or without enantiomeric separation.

  5. Evaluation of a new contact technology for a planar high-purity germanium double-sided strip detector

    NASA Astrophysics Data System (ADS)

    Jackson, Emily

    This thesis is an evaluation of a new electrode technology for segmented germanium gamma-ray detectors. The detector assessed herein is a planar high-purity germanium wafer (a LEPS or low-energy photon spectrometer) with 16 photolithographic-deposited, amorphous-germanium contacts on either side. This new contact material is shown to be an improvement over the current standard, lithium and boron electrodes, in both ease-of-manufacture and in performance. The symmetry gained with the use of one material for all the contacts is shown to greatly reduce the difference in energy collected by strips on either side. The stability of the amorphous germanium allows for finer electrode segmentation, reducing the gap between each strip. This smaller gap leads to a more uniform electric field in the active volume and ultimately less charge loss between strips. These improvements are quantified with the analysis of the energy difference and distribution of one- and two-hit interactions in the crystal by mono-energetic gamma rays from a 137Cs source. The detector is shown to be a major step forward in the development of contact technologies necessary for the application of position-sensitive gamma-detection outside of fundamental research, such as in nuclear medicine, astrophysics, and homeland security.

  6. Thermoluminescence (TL) properties and x-ray diffraction (XRD) analysis of high purity CaSO4:Dy TL material

    NASA Astrophysics Data System (ADS)

    Kamarudin, Nadira; Abdullah, Wan Saffiey Wan; Hamid, Muhammad Azmi Abdul; Dollah, Mohd Taufik

    2014-09-01

    This paper presents the characterization and TL properties of dysprosium (Dy) doped calcium sulfate (CaSO4) TL material produced by co-precipitation technique with 0.5mol% concentration of dopant. The morphology of the produced TL material was studied using scanning electron microscope (SEM) and the micrograph shows that rectangular parallelepiped shaped crystal with the average of 150 μm in length were produced. The crystallinity of the produced powder was studied using x-ray powder diffraction (XRD). The XRD spectra show that the TL material produced is high purity anhydrite CaSO4 with average crystallite size of 74 nm with orthorhombic crystal system. The TL behavior of produced CaSO4:Dy was studied using a TLD reader after exposure to gamma ray by Co60 source with the doses of 1,5 and 10 Gy. The glow curve shows linear response with glow peak around 230°C which is desired development in the field of radiation dosimetry.

  7. Recovery of silicon from sewage sludge for production of high-purity nano-SiO(2).

    PubMed

    Zou, Jinlong; Dai, Ying; Pan, Kai; Jiang, Baojiang; Tian, Chungui; Tian, Guohui; Zhou, Wei; Wang, Lei; Wang, Xue; Fu, Honggang

    2013-02-01

    Generation of excess sewage sludge has already caused many environmental problems. A novel investigation for recovery of Si from the carbonized raw sewage sludge (RS) has been conducted in this study. Results show that early rupture (by OH(-)) of Si-O-Si bond in the networks of SiO(4)(4-) tetrahedron is the key step for formation of RS-derived sodium silicate (Na(2)O·(SiO(2))(x)·(H(2)O)(y)). SiO(2) gel is formed through the silica colloidal-particles cohesion, which is partly affected by the bridging role of the hydrated Na(+) (1070.7eV). O1s peaks of the SiO(2) can be decomposed into two components, i.e. Si-O bridging oxygen atoms (532.4 eV) and hydroxyl groups (O-H, 533.0 eV). Intensity of the O-H stretching vibration bands around 3450 cm(-1) (residual Si-OH), which is inversely related to the condensation degree, decreases as sol pH increases. Properties of this high purity RS-SiO(2) enable it to have the potential for numerous technological (environmental and biotechnology) applications. Reutilization of RS for production of SiO(2) may provide an environmental benefits to communities by protecting water, soil and air.

  8. Refinement of Eutectic Si in High Purity Al-5Si Alloys with Combined Ca and P Additions

    NASA Astrophysics Data System (ADS)

    Ludwig, Thomas Hartmut; Li, Jiehua; Schaffer, Paul Louis; Schumacher, Peter; Arnberg, Lars

    2015-01-01

    The effects of combined additions of Ca and P on the eutectic Si in a series of high purity Al-5 wt pct Si alloys have been investigated with the entrained droplet technique and complementary sets of conventional castings. Differential scanning calorimetry (DSC) and thermal analysis were used to investigate the eutectic droplet undercooling and the recalescence undercooling, respectively. Optical microscopy, SEM, EPMA, and TEM were employed to characterize the resultant microstructures. It was found that 250 ppm Ca addition to Al-5Si wt pct alloys with higher P contents leads to a significant increase of the eutectic droplet undercooling. For low or moderate cooling rates, the TEM results underline that Ca additions do not promote Si twinning. Thus, a higher twin density cannot be expected in Ca containing Al-Si alloys after, e.g., sand casting. Consequently, a refinement of the eutectic Si from coarse flake-like to fine plate-like structure, rather than a modification of the eutectic Si to a fibrous morphology, was achieved. This strongly indicates that the main purpose of Ca additions is to counteract the coarsening effect of the eutectic Si imposed by higher P concentrations. Significant multiple Si twinning was observed in melt-spun condition; however, this can be attributed to the higher cooling rate. After DSC heating (slow cooling), most of Si twins disappeared. Thus, the well-accepted impurity-induced twinning mechanism may be not valid in the case of Ca addition. The possible refinement mechanisms were discussed in terms of nucleation and growth of eutectic Si. We propose that the pre-eutectic Al2Si2Ca phase and preferential formation of Ca3P2 deactivate impurity particles, most likely AlP, poisoning the nucleation sites for eutectic Si.

  9. In-vivo fluorescence dosimetry of aminolevulinate-based protoporphyrin IX (PpIX) accumulation in human nonmelanoma skin cancers and precancers

    NASA Astrophysics Data System (ADS)

    Warren, Christine B.; Lohser, Sara; Chang, Sung; Bailin, Philip A.; Maytin, Edward V.

    2009-06-01

    PDT is clinically useful for precancers (actinic keratoses; AK) of the skin, but the optimal duration for 5-ALA application is still controversial. For basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), cure rates remain inferior to surgical excision. Lack of knowledge about regional levels of PpIX levels within target tissues clearly contribute to these suboptimal results. To investigate PpIX levels achievable in human skin neoplasias in-vivo, a clinical study to monitor PpIX accumulation in vivo was performed. PpIX-fluorescence in patients undergoing ALA-PDT for facial AK was monitored via real-time in-vivo fluorescence dosimetry, with measurements q20 min following application of 5-ALA (Levulan Kerastick). PpIX accumulation followed linear kinetics in nearly all cases. The slopes varied widely, and did not correlate with clinical outcome in all patients. Some patients with a low accumulation of PpIX fluorescence had a good response to therapy, whereas others with high PpIX accumulation required repeat treatment (although not necessarily of the same lesion). PpIX accumulation rates did correlate to a certain degree with the overall amount of erythema. We conclude that unknown factors besides PpIX levels must be critical for the response to treatment. To assess the relationship between PpIX levels in various skin cancers, patients undergoing routine Mohs surgery for BCC or SCC were measured by in-vivo dosimetry at 2 h after 5-ALA application. Overall, a progressive increase in PpIX signal during malignant progression was observed, in the following rank order: Normal skin < AK < SCC ~ BCC.

  10. Unique low-molecular-weight lignin with high purity extracted from wood by deep eutectic solvents (DES): a source of lignin for valorization

    SciTech Connect

    Alvarez-Vasco, Carlos; Ma, Ruoshui; Quintero, Melissa; Guo, Mond; Geleynse, Scott; Ramasamy, Karthikeyan K.; Wolcott, Michael; Zhang, Xiao

    2016-01-01

    This paper reports a new method of applying Deep Eutectic Solvents (DES) for extracting lignin from woody biomass with high yield and high purity. DES mixtures prepared from Choline Chloride (ChCl) and four hydrogen-bond donors–acetic acid, lactic acid, levulinic acid and glycerol–were evaluated for treatment of hardwood (poplar) and softwood (D. fir). It was found that these DES treatments can selectively extract a significant amount of lignin from wood with high yields: 78% from poplar and 58% from D. fir. The extracted lignin has high purity (95%) with unique structural properties. We discover that DES can selectively cleave ether linkages in wood lignin and facilitate lignin removal from wood. The mechanism of DES cleavage of ether bonds between phenylpropane units was investigated. The results from this study demonstrate that DES is a promising solvent for wood delignification and the production of a new source of lignin with promising potential applications.

  11. Zn protoporphyrin IX is formed not from heme but from protoporphyrin IX.

    PubMed

    Wakamatsu, Jun-Ichi; Okui, Jun; Hayashi, Nobutaka; Nishimura, Takanori; Hattori, Akihito

    2007-12-01

    We examined the effects of exogenous myoglobin, a bivalent chelator, and nitrite on Zn protoporphyrin IX (ZPP) formation by using model systems. ZPP was formed in a model solution without addition of exogenous myoglobin. After incubation, the amount of ZPP in a model solution was increased but that of heme was not decreased compared with the amounts before incubation. Protoporphyrin IX (PPIX) instead of ZPP also accumulated in a model solution with addition of EDTA, but the amount of heme was not reduced. These results suggested that ZPP was not formed by the Fe-Zn substitution in heme but was formed by the insertion of Zn into PPIX, which was formed independently. The fact that the effects of various factors in model systems with/without addition of a bivalent chelator were similar suggested that ZPP formation was strongly affected by PPIX formation. Inhibition of PPIX formation by nitrite might be the reason for the low levels of ZPP in cured meats.

  12. Effect of small additions of silicon, iron, and aluminum on the room-temperature tensile properties of high-purity uranium

    SciTech Connect

    Ludwig, R.L.

    1983-11-14

    Eleven binary and ternary alloys of uranium and very low concentrations of iron, silicon, and aluminum were prepared and tested for room-temperature tensile properties after various heat treatments. A yield strength approximately double that of high-purity derby uranium was obtained from a U-400 ppM Si-200 ppM Fe alloy after beta solution treatment and alpha aging. Higher silicon plus iron alloy contents resulted in increased yield strength, but showed an unacceptable loss of ductility.

  13. Reconsidering the Status of Title IX.

    ERIC Educational Resources Information Center

    Hammer, Ben

    2003-01-01

    Discusses the controversy over Title IX and women's participation in college athletics. Critics say the mandate shortchanges men's teams, while proponents say that women's sports programs remain underfunded in spite of Title IX. Describes some proposed modifications to Title IX and their potential effects. (SLD)

  14. Ionic liquid-based extraction followed by graphite-furnace atomic absorption spectrometry for the determination of trace heavy metals in high-purity iron metal.

    PubMed

    Matsumiya, Hiroaki; Kato, Tatsuya; Hiraide, Masataka

    2014-02-01

    The analysis of high-purity materials for trace impurities is an important and challenging task. The present paper describes a facile and sensitive method for the determination of trace heavy metals in high-purity iron metal. Trace heavy metals in an iron sample solution were rapidly and selectively preconcentrated by the extraction into a tiny volume of an ionic liquid [1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide] for the determination by graphite-furnace atomic absorption spectrometry (GFAAS). A nitrogen-donating neutral ligand, 2,4,6-tris(2-pyridyl)-1,3,5-triazine (TPTZ), was found to be effective in the ionic liquid-based selective extraction, allowing the nearly complete (~99.8%) elimination of the iron matrix. The combination with the optimized GFAAS was successful. The detectability reached sub-μg g(-1) levels in iron metal. The novel use of TPTZ in ionic liquid-based extraction followed by GFAAS was successfully applied to the determination of traces of Co, Ni, Cu, Cd, and Pb in certified reference materials for high-purity iron metal.

  15. Preparation of High Purity Crystalline Silicon by Electro-Catalytic Reduction of Sodium Hexafluorosilicate with Sodium below 180°C

    PubMed Central

    Chen, Yuan; Liu, Yang; Wang, Xin; Li, Kai; Chen, Pu

    2014-01-01

    The growing field of silicon solar cells requires a substantial reduction in the cost of semiconductor grade silicon, which has been mainly produced by the rod-based Siemens method. Because silicon can react with almost all of the elements and form a number of alloys at high temperatures, it is highly desired to obtain high purity crystalline silicon at relatively low temperatures through low cost process. Here we report a fast, complete and inexpensive reduction method for converting sodium hexafluorosilicate into silicon at a relatively low reaction temperature (∼200°C). This temperature could be further decreased to less than 180°C in combination with an electrochemical approach. The residue sodium fluoride is dissolved away by pure water and hydrochloric acid solution in later purifying processes below 15°C. High purity silicon in particle form can be obtained. The relative simplicity of this method might lead to a low cost process in producing high purity silicon. PMID:25153509

  16. [Title IX and Intercollegiate Athletics.

    ERIC Educational Resources Information Center

    Department of Health , Education, and Welfare, Washington., DC. Office of the Secretary.

    Title IX of the 1972 Education Amendments is the topic of these Department of Health, Education, and Welfare (DHEW) notices, which include both a proposed policy interpretation regarding intercollegiate athletic programs and a proposed amendment regarding federal regulation of school dress codes. The purpose of the first action is to ensure that…

  17. Sub-band gap photo-enhanced secondary electron emission from high-purity single-crystal chemical-vapor-deposited diamond

    NASA Astrophysics Data System (ADS)

    Yater, J. E.; Shaw, J. L.; Pate, B. B.; Feygelson, T. I.

    2016-02-01

    Secondary-electron-emission (SEE) current measured from high-purity, single-crystal (100) chemical-vapor-deposited diamond is found to increase when sub-band gap (3.06 eV) photons are incident on the hydrogenated surface. Although the light does not produce photoemission directly, the SEE current increases by more than a factor of 2 before saturating with increasing laser power. In energy distribution curves (EDCs), the emission peak shows a corresponding increase in intensity with increasing laser power. However, the emission-onset energy in the EDCs remains constant, indicating that the bands are pinned at the surface. On the other hand, changes are observed on the high-energy side of the distribution as the laser power increases, with a well-defined shoulder becoming more pronounced. From an analysis of this feature in the EDCs, it is deduced that upward band bending is present in the near-surface region during the SEE measurements and this band bending suppresses the SEE yield. However, sub-band gap photon illumination reduces the band bending and thereby increases the SEE current. Because the bands are pinned at the surface, we conclude that the changes in the band levels occur below the surface in the electron transport region. Sample heating produces similar effects as observed with sub-band gap photon illumination, namely, an increase in SEE current and a reduction in band bending. However, the upward band bending is not fully removed by either increasing laser power or temperature, and a minimum band bending of ˜0.8 eV is established in both cases. The sub-band gap photo-excitation mechanism is under further investigation, although it appears likely at present that defect or gap states play a role in the photo-enhanced SEE process. In the meantime, the study demonstrates the ability of visible light to modify the electronic properties of diamond and enhance the emission capabilities, which may have potential impact for diamond-based vacuum electron

  18. Sub-band gap photo-enhanced secondary electron emission from high-purity single-crystal chemical-vapor-deposited diamond

    SciTech Connect

    Yater, J. E. Shaw, J. L.; Pate, B. B.; Feygelson, T. I.

    2016-02-07

    Secondary-electron-emission (SEE) current measured from high-purity, single-crystal (100) chemical-vapor-deposited diamond is found to increase when sub-band gap (3.06 eV) photons are incident on the hydrogenated surface. Although the light does not produce photoemission directly, the SEE current increases by more than a factor of 2 before saturating with increasing laser power. In energy distribution curves (EDCs), the emission peak shows a corresponding increase in intensity with increasing laser power. However, the emission-onset energy in the EDCs remains constant, indicating that the bands are pinned at the surface. On the other hand, changes are observed on the high-energy side of the distribution as the laser power increases, with a well-defined shoulder becoming more pronounced. From an analysis of this feature in the EDCs, it is deduced that upward band bending is present in the near-surface region during the SEE measurements and this band bending suppresses the SEE yield. However, sub-band gap photon illumination reduces the band bending and thereby increases the SEE current. Because the bands are pinned at the surface, we conclude that the changes in the band levels occur below the surface in the electron transport region. Sample heating produces similar effects as observed with sub-band gap photon illumination, namely, an increase in SEE current and a reduction in band bending. However, the upward band bending is not fully removed by either increasing laser power or temperature, and a minimum band bending of ∼0.8 eV is established in both cases. The sub-band gap photo-excitation mechanism is under further investigation, although it appears likely at present that defect or gap states play a role in the photo-enhanced SEE process. In the meantime, the study demonstrates the ability of visible light to modify the electronic properties of diamond and enhance the emission capabilities, which may have potential impact for diamond-based vacuum electron

  19. Ongoing advances in quantitative PpIX fluorescence guided intracranial tumor resection (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Olson, Jonathan D.; Kanick, Stephen C.; Bravo, Jaime J.; Roberts, David W.; Paulsen, Keith D.

    2016-03-01

    Aminolevulinc-acid induced protoporphyrin IX (ALA-PpIX) is being investigated as a biomarker to guide neurosurgical resection of brain tumors. ALA-PpIX fluorescence can be observed visually in the surgical field; however, raw fluorescence emissions can be distorted by factors other than the fluorophore concentration. Specifically, fluorescence emissions are mixed with autofluorescence and attenuated by background absorption and scattering properties of the tissue. Recent work at Dartmouth has developed advanced fluorescence detection approaches that return quantitative assessments of PpIX concentration, which are independent of background optical properties. The quantitative fluorescence imaging (qFI) approach has increased sensitivity to residual disease within the resection cavity at the end of surgery that was not visible to the naked eye through the operating microscope. This presentation outlines clinical observations made during an ongoing investigation of ALA-PpIX based guidance of tumor resection. PpIX fluorescence measurements made in a wide-field hyperspectral imaging approach are co-registered with point-assessment using a fiber optic probe. Data show variations in the measured PpIX accumulation among different clinical tumor grades (i.e. high grade glioma, low grade glioma), types (i.e. primary tumors. metastases) and normal structures of interest (e.g. normal cortex, hippocampus). These results highlight the contrast enhancement and underscore the potential clinical benefit offered from quantitative measurements of PpIX concentration during resection of intracranial tumors.

  20. Effect of low-energy alpha-particles irradiation on surface structure and physical-mechanical properties of high-purity tungsten

    NASA Astrophysics Data System (ADS)

    Aldabergenova, T. M.; Kislitsin, S. B.; Larionov, A. S.; Yar-Mukhamedova, G. S.

    2016-11-01

    Effect of radiation by low-energy alpha-particles on the surface structure and physical-mechanical properties of high-purity tungsten was studied. Samples of tungsten were irradiated by 4He+2 ions with the energy of 45 keV at low-energy channel of accelerator DC-60 in Astana branch of Institute Nuclear Physics. Irradiation fluence was 1.5 × 1018 cm-2, irradiation temperature was 150°C. Experimentally found that irradiation with low-energy alpha particles results in formation of helium filled bubbles in the straggling region.

  1. Influence of the chloride ion concentration on the corrosion of high-purity Mg, ZE41 and AZ91 in buffered Hank's solution.

    PubMed

    Taltavull, C; Shi, Z; Torres, B; Rams, J; Atrens, A

    2014-02-01

    This research studied the influence of the chloride ion concentration on the corrosion behaviour of high-purity magnesium (Mg) and two Mg alloys in Hank's solution, using hydrogen evolution and weight loss. A buffer based on CO2 and NaHCO3 was used to maintain the pH constant. The corrosion behaviour was governed by a partially protective surface film, and film breakdown by the chloride ions. The carbonated calcium phosphate layer that formed in Hank's solution was important in determining the protective properties of the surface film.

  2. Breakpoint of a balanced translocation (X:14) (q27.1;q32.3) in a girl with severe hemophilia B maps proximal to the factor IX gene.

    PubMed

    Di Paola, J; Goldman, T; Qian, Q; Patil, S R; Schutte, B C; Schute, B C

    2004-03-01

    Hemophilia B is an X-linked bleeding disorder caused by the deficiency of coagulation factor (F)IX, with an estimated prevalence of 1 in 30 000 male births. It is almost exclusively seen in males with rare exceptions. We report a girl who was diagnosed with severe (<1%) FIX deficiency at 4 months of age. Cytogenetic studies in the patient showed a balanced translocation between one of the X-chromosomes and chromosome 14, with breakpoints at bands Xq27.1 and 14q32.3. Both parents were found to have normal chromosomes. Late replication studies by incorporation of 5-bromodeoxyuridine showed non-random inactivation of the normal X-chromosome, a phenomenon frequently seen in balanced X/autosome translocations. To map the breakpoint, fluorescent in-situ hybridization was performed. A PAC DNA probe, RP6-88D7 (which contains the FIX gene) hybridized only on the normal chromosome X as well as onto the derivative 14. Using a PAC DNA probe, RP11-963P9 that is located proximal to the FIX gene, we obtained signals on the normal and derivative X and also on the derivative 14. We conclude that the breakpoint is located within the DNA sequence of this clone mapping proximal to the FIX gene. Since the FIX gene seems to be intact in the derivative 14, the breakpoint may affect an upstream regulatory sequence that subjects the gene to position effect variegation (PEV).

  3. Mechanisms of Vesicular Stomatitis Virus Inactivation by Protoporphyrin IX, Zinc-protoporphyrin IX and Mesoporphyrin IX.

    PubMed

    Cruz-Oliveira, Christine; Almeida, Andreza F; Freire, João M; Caruso, Marjolly B; Morando, Maria A; Ferreira, Vivian N S; Assunção-Miranda, Iranaia; Gomes, Andre M O; Castanho, Miguel A R B; Da Poian, Andrea T

    2017-03-27

    Virus resistance to antiviral therapies is an increasing concern that makes urgent the development of broad spectrum antiviral drugs. Targeting viral envelope, a component shared by a large number of viruses, emerges as a promising strategy to overcome this problem. Natural and synthetic porphyrins, due to their relative hydrophobicity and pro-oxidant character, are good candidates for antivirals' development. In the present work, we characterized the antiviral activity of protoprophyrin IX (PPIX), Zn-protoporphyrin IX (ZnPPIX) and mesoporphyrin IX (MPIX) against vesicular stomatitis virus (VSV), and evaluated the mechanisms involved in this activity. VSV treatment with PPIX, ZnPPIX and MPIX promoted a dose-dependent virus inactivation, which was potentiated by porphyrin photoactivation. All three porphyrins inserted into lipid vesicles and disturbed viral membrane organization. In addition, the porphyrins also affected viral proteins, inducing VSV glycoprotein cross-linking, which was enhanced by porphyrin photoactivation. Virus incubation with sodium azide and α-tocopherol partially protected VSV inactivation by porphyrins, suggesting that singlet oxygen ((1)O2) was the main reactive oxygen species produced by photoactivation of these molecules. Furthermore, (1)O2 was detected by DMA oxidation in photoactivated porphyrin samples, reinforcing this hypothesis. These results reveal the potential therapeutic application of PPIX, ZnPPIX and MPIX as good models for broad antiviral drug design.

  4. Determination of rare earth elements in high purity rare earth oxides by liquid chromatography, thermionic mass spectrometry and combined liquid chromatography/thermionic mass spectrometry

    NASA Astrophysics Data System (ADS)

    Stijfhoorn, D. E.; Stray, H.; Hjelmseth, H.

    1993-03-01

    A high-performance liquid Chromatographie (HPLC) method for the determination of rare earth elements in rocks has been modified and used for the determination of rare earth elements (REE) in high purity rare earth oxides. The detection limit was 1-1.5 ng or 2-3 mg/kg when a solution corresponding to 0.5 mg of the rare earth oxide was injected. The REE determination was also carried out by adding a mixture of selected REE isotopes to the sample and analysing the collected HPLC-fractions by mass spectrometry (MS) using a thermionic source. Since the matrix element was not collected, interference from this element during the mass spectrometric analysis was avoided. Detection limits as low as 0.5 mg/kg could then be obtained. Detection limits as low as 0.05 mg/kg were possible by MS without HPLC-pre-separation, but this approach could only be used for those elements that were not affected by the matrix. Commercial samples of high purity Nd 2O 3, Gd 2O 3 and Dy 2O 3 were analysed in this study, and a comparison of results obtained by HPLC, combined HPLC/MS and direct MS are presented.

  5. Determination of traces of rubidium in high purity cesium chloride by electrothermal atomic absorption spectrometry (ETAAS) using boric acid as a modifier.

    PubMed

    Dash, K; Thangavel, S; Chaurasia, S C; Arunachalam, J

    2007-02-12

    The use of boric acid as a modifier for the determination of trace amount of rubidium in high purity cesium chloride matrix by electrothermal atomic absorption is described. It was found that the negative influence of the chloride matrix could not be eliminated using stabilized temperature platform (STPF) alone. Due to the high dissociation energy (D(0)=427 kJ mol(-1)) of rubidium chloride, it was difficult to dissociate in the gas phase and hence is lost. Elimination of interferences was achieved by the addition of boric acid as a chemical modifier. Diluted cesium chloride samples (5%, m/v) were analyzed applying the standard addition method. The characteristic mass of 24 pg was obtained. The detection limit of the proposed method is around 26 ng g(-1). The developed method was applied to the determination of traces of rubidium in high purity cesium chloride samples. The data obtained by this method were in good agreement with those obtained by other independent method like FAAS.

  6. Pre-degenerated peripheral nerves co-cultured with bone marrow-derived cells: a new technique for harvesting high-purity Schwann cells

    PubMed Central

    Wang, Xiao-pan; Wu, Min; Guan, Jian-zhong; Wang, Zhao-dong; Gao, Xu-bin; Liu, Yang-yang

    2016-01-01

    Schwann cells play an important role in the peripheral nervous system, especially in nerve repair following injury, so artificial nerve regeneration requires an effective technique for obtaining purified Schwann cells. In vivo and in vitro pre-degeneration of peripheral nerves have been shown to obtain high-purity Schwann cells. We believed that in vitro pre-degeneration was simple and controllable, and available for the clinic. Thus, we co-cultured the crushed sciatic nerves with bone marrow-derived cells in vitro. Results demonstrated that, 3 hours after injury, a large number of mononuclear cells moved to the crushed nerves and a large number of bone marrow-derived cells infiltrated the nerve segments. These changes promoted the degradation of the nerve segments, and the dedifferentiation and proliferation of Schwann cells. Neural cell adhesion molecule and glial fibrillary acidic protein expression were detected in the crushed nerves. Schwann cell yield was 9.08 ± 2.01 × 104/mg. The purity of primary cultured Schwann cells was 88.4 ± 5.79%. These indicate a successful new method for obtaining Schwann cells of high purity and yield from adult crushed sciatic nerve using bone marrow-derived cells. PMID:27904498

  7. 34 CFR Subject Index to Title IX... - Subject Index to Title IX Preamble and Regulation 1

    Code of Federal Regulations, 2010 CFR

    2016-07-01

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    Code of Federal Regulations, 2010 CFR

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    Code of Federal Regulations, 2010 CFR

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    Code of Federal Regulations, 2010 CFR

    2002-07-01

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  4. 45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

    Code of Federal Regulations, 2010 CFR

    2001-10-01

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    Code of Federal Regulations, 2010 CFR

    2006-07-01

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  6. 45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

    Code of Federal Regulations, 2010 CFR

    2007-10-01

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  7. 45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

    Code of Federal Regulations, 2010 CFR

    2005-10-01

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    Code of Federal Regulations, 2010 CFR

    1999-10-01

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  9. 45 CFR Subject Index to Title IX... - Subject Index to Title IX Preamble and Regulation 1

    Code of Federal Regulations, 2010 CFR

    2015-10-01

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  10. 45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

    Code of Federal Regulations, 2010 CFR

    2004-10-01

    ... 45 Public Welfare 1 2004-10-01 2004-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare DEPARTMENT OF HEALTHAND..., Index Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers are in...

  11. 34 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

    Code of Federal Regulations, 2010 CFR

    2003-07-01

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  12. 45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

    Code of Federal Regulations, 2010 CFR

    2009-10-01

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  13. [Separation with ion exchange fiber column and determination of La, Nd, Eu and Gd in high purity ytterbium oxide by ICP-AES].

    PubMed

    Gong, Qi; Chen, Jie; Ji, Ri-Wen; Pan, Xue-Zhen; Wu, Juan

    2010-02-01

    In the present paper, trace La, Nd, Eu and Gd were separated and enriched with strong acid ion exchange fiber column from high purity Yb2 O3, and then determined by Optima 5 300 DV ICP-AES. The ion exchange fiber's breakthrough capacity for Yb was 134 mg x g(-1). The separation condition using 4.0 g fiber column was that after the test solution (pH = 3.0) was fed into the ion exchange fiber column at 1.0 mL x min(-1), the column was pre--leached by dilute nitric acid (pH = 3.00) of 80 mL at 1.5 mL x min(-1) at first, and then was eluted by 0.01 mol x L(-1) ammonium EDTA (pH = 5.00) at the same flow rate. The results showed that 10 mg Yb could reach the baseline separation with 0.100 microg of the four rare earth impurities, and after 100 mg Yb in feed solution had been separated, only 0.017 1 microg x mL(-1) Yb remained in the impurities enriched effluent. When the concentration of Yb2 O3 is less than 100 microg x mL(-1) (87.8 microg x mL(-1) Yb), the matrix interference from Yb on with determination of La, Nd, Eu and Gd can be neglected. The enrichment factors were 3.68 x 10(5) for La2 O3, 4.20 x 10(5) for Nds O3, 3.82 x 10(5) for Eu2 O3, and 4.01 x 10(5) for Gd2 O3, and the detection limits of the method were 0.005 0, 0.014, 0.001 8 and 0.008 2 pg x mL(-1) for La2 O3, Nd2 O3, Eu2 O3 and Gd2 O3 respectively. The proposed method was applied to the analysis of 99.99% Yb2 O3 with RSD (%, n = 5) of 6.2, 5.9, 7.3 and 2.5 for La2 O3, Nd2 O3, Eu2 O3 and Gd2 O3 respectively, and the average recoveries of standard addition were 94.2%, 107%, 97.8% and 102% for La2 O3, Nd2 O3, Eu2 O3 and Gd2 O3 respectively. The calibration curve did not need matrix matching with Yb, and the analysis period was within 4 hour.

  14. Exonuclease IX of Escherichia coli.

    PubMed Central

    Shafritz, K M; Sandigursky, M; Franklin, W A

    1998-01-01

    The bacteria Escherichia coli contains several exonucleases acting on both double- and single-stranded DNA and in both a 5'-->3' and 3'-->5' direction. These enzymes are involved in replicative, repair and recombination functions. We have identified a new exonuclease found in E.coli, termed exonuclease IX, that acts preferentially on single-stranded DNA as a 3'-->5' exonuclease and also functions as a 3'-phosphodiesterase on DNA containing 3'-incised apurinic/apyrimidinic (AP) sites to remove the product trans -4-hydroxy-2-pentenal 5-phosphate. The enzyme showed essentially no activity as a deoxyribophosphodiesterase acting on 5'-incised AP sites. The activity was isolated as a glutathione S-transferase fusion protein from a sequence of the E.coli genome that was 60% identical to a 260 bp region of the small fragment of the DNA polymerase I gene. The protein has a molecular weight of 28 kDa and is free of AP endonuclease and phosphatase activities. Exonuclease IX is expressed in E.coli , as demonstrated by reverse transcription-PCR, and it may function in the DNA base excision repair and other pathways. PMID:9592142

  15. Title IX and Sex Discrimination. Revised.

    ERIC Educational Resources Information Center

    Office for Civil Rights (ED), Washington, DC.

    Title IX of the Education Amendments of 1972 protects people from discrimination based on sex in education programs or activities that receive Federal financial assistance. This brochure outlines the responsibilities of education programs and activities covered by Title IX, the responsibilities of the Office for Civil Rights (OCR) in enforcing…

  16. Title IX and Home Economics Instruction

    ERIC Educational Resources Information Center

    Thurston, Paul W.

    1977-01-01

    The following are discussed with reference to title IX of the Education Amendments of 1972, which prohibit sex discrimination in federally-supported educational programs: What is title IX? The letter of the law--can the school limit home economics to girls? Is a school in noncompliance if over 75 percent of the students in a home economics class…

  17. Statistical Evidence and Compliance with Title IX

    ERIC Educational Resources Information Center

    Cheslock, John J.; Eckes, Suzanne E.

    2008-01-01

    The scope of Title IX clearly includes all aspects of education, but the legislation's application to college athletics receives the most attention. Athletics programs, unlike most academic activities, are sex segregated, so the proper interpretation of the intercollegiate athletics provisions of Title IX is less clear-cut. This article examines…

  18. Efficacy and safety of a recombinant factor IX (Bax326) in previously treated patients with severe or moderately severe haemophilia B undergoing surgical or other invasive procedures: a prospective, open-label, uncontrolled, multicentre, phase III study.

    PubMed

    Windyga, J; Lissitchkov, T; Stasyshyn, O; Mamonov, V; Ghandehari, H; Chapman, M; Fritsch, S; Wong, W-Y; Pavlova, B G; Abbuehl, B E

    2014-09-01

    Haemostatic management of haemophilia B patients undergoing surgery is critical to patient safety. The aim of this ongoing prospective trial was to investigate the haemostatic efficacy and safety of a recombinant factor IX (rFIX) (Bax326) in previously treated subjects (12-65 years, without history of FIX inhibitors) with severe or moderately severe haemophilia B, undergoing surgical, dental or other invasive procedures. Haemostatic efficacy was assessed according to a predefined scale. Blood loss was compared to the average and maximum blood loss predicted preoperatively. Haemostatic FIX levels were achieved peri- and postoperatively in 100% of subjects (n = 14). Haemostasis was 'excellent' intraoperatively in all patients and postoperatively in those without a drain, and 'excellent' or 'good' at the time of drain removal and day of discharge in those with a drain employed. Following the initial dose, the mean FIX activity level rose from 6.55% to 107.58% for major surgeries and from 3.60% to 81.4% for minor surgeries. Actual vs. predicted blood loss matched predicted intraoperative blood loss but was equal to or higher than (but less than 150%) the maximum predicted postoperative blood loss reflecting the severity of procedure and FIX requirements. There were no related adverse events, severe allergic reactions or thrombotic events. There was no evidence that BAX326 increased the risk of inhibitor or binding antibody development to FIX. BAX326 was safe and effective for peri-operative management of 14 subjects with severe and moderately severe haemophilia B.

  19. Pharmacokinetics, efficacy and safety of BAX326, a novel recombinant factor IX: a prospective, controlled, multicentre phase I/III study in previously treated patients with severe (FIX level <1%) or moderately severe (FIX level ≤2%) haemophilia B.

    PubMed

    Windyga, J; Lissitchkov, T; Stasyshyn, O; Mamonov, V; Rusen, L; Lamas, J L; Oh, M-S; Chapman, M; Fritsch, S; Pavlova, B G; Wong, W-Y; Abbuehl, B E

    2014-01-01

    BAX326 is a recombinant factor IX (rFIX; nonacog gamma) manufactured without the addition of any materials of human or animal origin, and with two viral inactivation steps (solvent/detergent treatment and 15 nm nanofiltration). The aim of this prospective trial was to investigate the pharmacokinetics, haemostatic efficacy and safety of BAX326 in previously treated patients aged 12-65 years with severe or moderately severe haemophilia B. BAX326 was safe and well tolerated in all 73 treated subjects; adverse events considered related to treatment (2.7% incidence, all non-serious) were transient and mild, and no hypersensitivity reactions, inhibitor formation or thrombotic events were observed. Pharmacokinetic (PK) equivalence (n = 28) between BAX326 and a licensed rFIX was confirmed in terms of the ratio of geometric mean AUC(0-72) h per dose. Twice-weekly prophylaxis [mean duration 6.2 (±0.7) months; 1.8 (±0.1) infusions per week, 49.5 (±4.8) IU kg(-1) per infusion] was effective in preventing bleeding episodes, with a significantly lower (79%, P < 0.001) annualized bleed rate (4.2) compared to an on-demand treatment in a historical control group (20.0); 24 of 56 subjects on prophylaxis (43%) did not bleed throughout the study observation period. Of 249 total acute bleeds, 211 (84.7%) were controlled with one to two infusions of BAX326. Haemostatic efficacy at resolution of bleed was rated excellent or good in 96.0% of all treated bleeding episodes. The results of this study indicate that BAX326 is safe and efficacious in treating bleeds and routine prophylaxis in patients aged 12 years and older with haemophilia B.

  20. Surgical experience with rFVIIa (NovoSeven) in congenital haemophilia A and B patients with inhibitors to factors VIII or IX.

    PubMed

    Valentino, L A; Cooper, D L; Goldstein, B

    2011-07-01

    Patients with congenital haemophilia with inhibitors are at risk of peri-operative bleeding complications, since replacement of the missing coagulation factor is ineffective, presenting a therapeutic challenge in elective or emergency surgery. Therefore, the management of peri-operative bleeding requires the use of bypassing agents, such as recombinant activated FVII (rFVIIa, NovoSeven(®) ). This article presents an updated evaluation of the safety and effectiveness of rFVIIa in the treatment of peri-operative bleeding in this patient population. Surgical and other medical procedures managed with rFVIIa from two randomized clinical trials, the Hemophilia Research Society/Hemophilia and Thrombosis Research Society (HRS/HTRS) registry databases and the medical literature were analysed. There were 395 rFVIIa-treated procedures (261 surgical, 89 dental and 45 other medical procedures) reported for 263 congenital haemophilia patients with inhibitors. In trials, initial rFVIIa dosing was 35-90 mcg kg(-1) bolus injection or 50 mcg kg(-1) h(-1) continuous infusion. Dosing in the registries and literature was more variable. Recombinant FVIIa effectiveness was comparable across data sources, with an overall rate of 84% (333/395). The incidence of thrombotic events was very low (0.4% of patients and 0.025% of procedures). Prior to the US approval of rFVIIa in 1999, surgical procedures in congenital haemophilia patients with inhibitors were often considered too risky. Recombinant FVIIa has consistently demonstrated effectiveness in treatment of bleeding in these patients during such procedures. Thrombotic events were rare. This analysis confirms the value of corroborating clinical trial results with post-marketing surveillance registries to assess small patient populations with clinically challenging management decisions.

  1. Possible influence of surface oxides on the optical response of high-purity niobium material used in the fabrication of superconducting radio frequency cavity

    NASA Astrophysics Data System (ADS)

    Singh, Nageshwar; Deo, M. N.; Roy, S. B.

    2016-09-01

    We have investigated the possible influence of surface oxides on the optical properties of a high-purity niobium (Nb) material for fabrication of superconducting radio frequency (SCRF) cavities. Various peaks in the infrared region were identified using Fourier transform infrared and Raman spectroscopy. Optical response functions such as complex refractive index, dielectric and conductivity of niobium were compared with the existing results on oxides free Nb and Cu. It was observed that the presence of a mixture of niobium-oxides, and probably near other surface impurities, appreciably influence the conducting properties of the material causing deviation from the typical metallic characteristics. In this way, the key result of this work is the observation, identification of vibrational modes of some of surface complexes and study of its influences on the optical responses of materials. This method of spectroscopic investigation will help in understanding the origin of degradation of performance of SCRF cavities.

  2. Characteristics of signals originating near the lithium-diffused N+ contact of high purity germanium p-type point contact detectors

    DOE PAGES

    Aguayo, E.; Amman, M.; Avignone, F. T.; ...

    2012-11-09

    A study of signals originating near the lithium-diffused n+ contact of p-type point contact (PPC) high purity germanium detectors (HPGe) is presented. The transition region between the active germanium and the fully dead layer of the n+ contact is examined. Energy depositions in this transition region are shown to result in partial charge collection. This provides a mechanism for events with a well defined energy to contribute to the continuum of the energy spectrum at lower energies. A novel technique to quantify the contribution from this source of background is introduced. Furthermore, experiments that operate germanium detectors with a verymore » low energy threshold may benefit from the methods presented herein.« less

  3. RADIOCHEMICAL PURITY OF MO AND TC SOLUTION OBTAINED AFTER IRRADIATION AND DISSOLUTION OF MO-100-ENRICHED AND ULTRA-HIGH-PURITY NATURAL MO DISKS

    SciTech Connect

    Tkac, Peter; Gromov, Roman; Chemerisov, Sergey D.; Rotsch, David A.; Vandegrift, George F.

    2016-09-01

    Four irradiations of ultra-high-purity natural Mo targets and one irradiation using 97.4% Mo-100-enriched material were performed. The purpose of these irradiations was to determine whether the presence of Sn stabilizer in the H2O2 used for the dissolution of sintered Mo disks can affect the radiochemical purity of the final K2MoO4 in 5M KOH solution. Results from radiochemical purity tests performed using thin-layer paper chromatography show that even 2– 3× excess of Sn-stabilized H2O2 typically used for dissolution of sintered Mo disks did not affect the radiochemical purity of the final product.

  4. An improved back-flush-to-vent gas chromatographic method for determination of trace permanent gases and carbon dioxide in ultra-high purity ammonia.

    PubMed

    Trubyanov, Maxim M; Mochalov, Georgy M; Vorotyntsev, Ilya V; Vorotyntsev, Andrey V; Suvorov, Sergey S; Smirnov, Konstantin Y; Vorotyntsev, Vladimir M

    2016-05-20

    A novel method for rapid, quantitative determination of trace permanent gases and carbon dioxide in ultra-high purity ammonia by dual-channel two-dimensional GC-PDHID is presented. An improved matrix back-flush-to-vent approach combining back-flush column switching technique with auxiliary NaHSO4 ammonia trap is described. The NaHSO4 trap prevents traces of ammonia from entering the analytical column and is shown not to affect the impurity content of the sample. The approach allows shortening the analysis time and increasing the amount of measurements without extensive maintenance of the GC-system. The performance of the configuration has been evaluated utilizing ammonia- and helium-based calibration standards. The method has been applied for the analysis of 99.9999+% ammonia purified by high-pressure distillation at the production site.

  5. Thermal evolution of high-purity and boron-doped sub-microcrystalline Ni{sub 3}Al produced by severe plastic deformation

    SciTech Connect

    Korznikov, A.V.; Korznikova, G.F.; Idrisova, S.R.; Dimitrov, O.; Dallas, J.P.; Faudot, F.; Valiev, R.Z.

    1999-09-08

    The influence of boron on the structural stability of sub-microcrystalline Ni{sub 3}Al intermetallic compounds was investigated by comparing a high-purity material with a boron-doped (0.1 wt%) compound. The nanocrystalline structure was obtained by severe shear deformation under quasi-hydrostatic pressure. Residual electrical resistivity, Vickers microhardness, X-ray diffraction and transmission electron microscopy were used to characterize the material evolution during thermal treatments in the temperature range 293--1,313 K. After severe deformation the materials were disordered, with a small crystallite size of about 20 nm, similar in both materials. During isochronal anneals, the evolution of the microstructure, the long-range ordering and the recovery of the investigated properties took place at higher temperatures in the boron-doped compound, i.e. the thermal stability of the cold-worked structure was higher.

  6. Integrated Approach To Producing High-Purity Trehalose from Maltose by the Yeast Yarrowia lipolytica Displaying Trehalose Synthase (TreS) on the Cell Surface.

    PubMed

    Li, Ning; Wang, Hengwei; Li, Lijuan; Cheng, Huiling; Liu, Dawen; Cheng, Hairong; Deng, Zixin

    2016-08-10

    An alternative strategy that integrated enzyme production, trehalose biotransformation, and bioremoval in one bioreactor was developed in this study, thus simplifying the traditional procedures used for trehalose production. The trehalose synthase gene from a thermophilic archaea, Picrophilus torridus, was first fused to the YlPir1 anchor gene and then inserted into the genome of Yarrowia lipolytica, thus yielding an engineered yeast strain. The trehalose yield reached 73% under optimal conditions. The thermal and pH stabilities of the displayed enzyme were improved compared to those of its free form purified from recombinant Escherichia coli. After biotransformation, the glucose byproduct and residual maltose were directly fermented to ethanol by a Saccharomyces cerevisiae strain. Ethanol can be separated by distillation, and high-purity trehalose can easily be obtained from the fermentation broth. The results show that this one-pot procedure is an efficient approach to the economical production of trehalose from maltose.

  7. Characteristics of signals originating near the lithium-diffused N+ contact of high purity germanium p-type point contact detectors

    SciTech Connect

    Aguayo, E.; Amman, M.; Avignone, F. T.; Barabash, A. S.; Barton, P. J.; Beene, J. R.; Bertrand, F. E.; Boswell, M.; Brudanin, V.; Busch, M.; Chan, Y. -D.; Christofferson, C. D.; Collar, J. I.; Combs, D. C.; Cooper, R. J.; Detwiler, J. A.; Doe, P. J.; Efremenko, Yu.; Egorov, V.; Ejiri, H.; Elliott, S. R.; Esterline, J.; Fast, J. E.; Fields, N.; Finnerty, P.; Fraenkle, F. M.; Galindo-Uribarri, A.; Gehman, V. M.; Giovanetti, G. K.; Green, M. P.; Guiseppe, V. E.; Gusey, K.; Hallin, A. L.; Hazama, R.; Henning, R.; Hoppe, E. W.; Horton, M.; Howard, S.; Howe, M. A.; Johnson, R. A.; Keeter, K. J.; Kidd, M. F.; Knecht, A.; Kochetov, O.; Konovalov, S. I.; Kouzes, R. T.; LaFerriere, B. D.; Leon, J.; Leviner, L. E.; Loach, J. C.; Looker, Q.; Luke, P. N.; MacMullin, S.; Marino, M. G.; Martin, R. D.; Merriman, J. H.; Miller, M. L.; Mizouni, L.; Nomachi, M.; Orrell, J. L.; Overman, N. R.; Perumpilly, G.; Phillips, D. G.; Poon, A. W. P.; Radford, D. C.; Rielage, K.; Robertson, R. G. H.; Ronquest, M. C.; Schubert, A. G.; Shima, T.; Shirchenko, M.; Snavely, K. J.; Steele, D.; Strain, J.; Timkin, V.; Tornow, W.; Varner, R. L.; Vetter, K.; Vorren, K.; Wilkerson, J. F.; Yakushev, E.; Yaver, H.; Young, A. R.; Yu, C. -H.; Yumatov, V.

    2012-11-09

    A study of signals originating near the lithium-diffused n+ contact of p-type point contact (PPC) high purity germanium detectors (HPGe) is presented. The transition region between the active germanium and the fully dead layer of the n+ contact is examined. Energy depositions in this transition region are shown to result in partial charge collection. This provides a mechanism for events with a well defined energy to contribute to the continuum of the energy spectrum at lower energies. A novel technique to quantify the contribution from this source of background is introduced. Furthermore, experiments that operate germanium detectors with a very low energy threshold may benefit from the methods presented herein.

  8. Monte Carlo simulation of gamma-ray interactions in an over-square high-purity germanium detector for in-vivo measurements

    NASA Astrophysics Data System (ADS)

    Saizu, Mirela Angela

    2016-09-01

    The developments of high-purity germanium detectors match very well the requirements of the in-vivo human body measurements regarding the gamma energy ranges of the radionuclides intended to be measured, the shape of the extended radioactive sources, and the measurement geometries. The Whole Body Counter (WBC) from IFIN-HH is based on an “over-square” high-purity germanium detector (HPGe) to perform accurate measurements of the incorporated radionuclides emitting X and gamma rays in the energy range of 10 keV-1500 keV, under conditions of good shielding, suitable collimation, and calibration. As an alternative to the experimental efficiency calibration method consisting of using reference calibration sources with gamma energy lines that cover all the considered energy range, it is proposed to use the Monte Carlo method for the efficiency calibration of the WBC using the radiation transport code MCNP5. The HPGe detector was modelled and the gamma energy lines of 241Am, 57Co, 133Ba, 137Cs, 60Co, and 152Eu were simulated in order to obtain the virtual efficiency calibration curve of the WBC. The Monte Carlo method was validated by comparing the simulated results with the experimental measurements using point-like sources. For their optimum matching, the impact of the variation of the front dead layer thickness and of the detector photon absorbing layers materials on the HPGe detector efficiency was studied, and the detector’s model was refined. In order to perform the WBC efficiency calibration for realistic people monitoring, more numerical calculations were generated simulating extended sources of specific shape according to the standard man characteristics.

  9. A combined arc-melting and tilt-casting furnace for the manufacture of high-purity bulk metallic glass materials.

    PubMed

    Soinila, E; Pihlajamäki, T; Bossuyt, S; Hänninen, H

    2011-07-01

    An arc-melting furnace which includes a tilt-casting facility was designed and built, for the purpose of producing bulk metallic glass specimens. Tilt-casting was chosen because reportedly, in combination with high-purity processing, it produces the best fatigue endurance in Zr-based bulk metallic glasses. Incorporating the alloying and casting facilities in a single piece of equipment reduces the amount of laboratory space and capital investment needed. Eliminating the sample transfer step from the production process also saves time and reduces sample contamination. This is important because the glass forming ability in many alloy systems, such as Zr-based glass-forming alloys, deteriorates rapidly with increasing oxygen content of the specimen. The challenge was to create a versatile instrument, in which high purity conditions can be maintained throughout the process, even when melting alloys with high affinity for oxygen. Therefore, the design provides a high-vacuum chamber to be filled with a low-oxygen inert atmosphere, and takes special care to keep the system hermetically sealed throughout the process. In particular, movements of the arc-melting electrode and sample manipulator arm are accommodated by deformable metal bellows, rather than sliding O-ring seals, and the whole furnace is tilted for tilt-casting. This performance of the furnace is demonstrated by alloying and casting Zr(55)Cu(30)Al(10)Ni(5) directly into rods up to ø 10 mm which are verified to be amorphous by x-ray diffraction and differential scanning calorimetry, and to exhibit locally ductile fracture at liquid nitrogen temperature.

  10. A hybrid enrichment process combining conjugated polymer extraction and silica gel adsorption for high purity semiconducting single-walled carbon nanotubes (SWCNT)

    NASA Astrophysics Data System (ADS)

    Ding, Jianfu; Li, Zhao; Lefebvre, Jacques; Cheng, Fuyong; Dunford, Jeffrey L.; Malenfant, Patrick R. L.; Humes, Jefford; Kroeger, Jens

    2015-09-01

    A novel purification process for the enrichment of sc-SWCNTs that combines selective conjugated polymer extraction (CPE) with selective adsorption using silica gel, termed hybrid-CPE (h-CPE), has been developed, providing a high purity sc-SWCNT material with a significant improvement in process efficiency and yield. Using the h-CPE protocol, a greater than 5 fold improvement in yield can be obtained compared to traditional CPE while obtaining sc-SWCNT with a purity >99.9% as assessed by absorption spectroscopy and Raman mapping. Thin film transistor devices using the h-CPE derived sc-SWCNTs as the semiconductor possess mobility values ranging from 10-30 cm2 V-1 s-1 and current ON/OFF ratio of 104-105 for channel lengths between 2.5 and 20 μm.A novel purification process for the enrichment of sc-SWCNTs that combines selective conjugated polymer extraction (CPE) with selective adsorption using silica gel, termed hybrid-CPE (h-CPE), has been developed, providing a high purity sc-SWCNT material with a significant improvement in process efficiency and yield. Using the h-CPE protocol, a greater than 5 fold improvement in yield can be obtained compared to traditional CPE while obtaining sc-SWCNT with a purity >99.9% as assessed by absorption spectroscopy and Raman mapping. Thin film transistor devices using the h-CPE derived sc-SWCNTs as the semiconductor possess mobility values ranging from 10-30 cm2 V-1 s-1 and current ON/OFF ratio of 104-105 for channel lengths between 2.5 and 20 μm. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr04851f

  11. Design, fabrication, performance and reliability of Pt- and RuO2-coated microrelays tested in ultra-high purity gas environments

    NASA Astrophysics Data System (ADS)

    de Boer, M. P.; Czaplewski, D. A.; Baker, M. S.; Wolfley, S. L.; Ohlhausen, J. A.

    2012-10-01

    We have fabricated, tested and analyzed the reliability of Pt- and RuO2-coated ohmic microrelays in ultra-high purity gas environments. RuO2-coated relays could survive 3 × 108 contact cycles without electrical degradation, while Pt-coated devices degraded after 105 cycles. Thermally actuated microrelays were fabricated using a process that employed a polysilicon surface-micromachined substructure. After releasing the devices, just a few blanket metal depositions were required to create the different coatings. This method allowed direct comparisons between different coating materials, and was enabled by a self-aligned shadow mask that provides electrical isolation between different traces. Testing was performed in a clean environment achieved through in situ ultra-high vacuum bakeouts, chamber cooling to <5 × 10-9 Torr and chamber refill with ultra-high purity gases. The RuO2 coatings were formed by two avenues—reactive sputtering and thermal oxidation. No significant difference in contact resistance or reliability was detected for these two deposition methods. For all coatings, post-test analysis by scanning electron microscopy and Auger electron spectroscopy indicated no difference in carbon concentration on real contact versus non-contacting areas, implying that carbon did not play a role in limiting the switches’ reliability. The Pt-coated switch reliability limit was attributed to surface wear rather than to the growth of a contaminating film. For the RuO2 switches, trace resistance was reduced by ten times using an Al underlayer, so that the total device resistance was compatible with commercial device requirements. Because RuO2 is expected to be resistant to hydrocarbon contamination, this work shows that the RuO2 coating provides a promising path toward achieving ultra-high reliability ohmic microswitches.

  12. Foundations for quantitative microstructural models to track evolution of the metallurgical state during high purity Nb cavity fabrication

    SciTech Connect

    Bieler, Thomas R; Wright, Neil T; Compton, Chris C

    2014-03-15

    The goal of the Materials Science SRF Cavity Group of Michigan State University and the National Superconducting Cyclotron has been (and continues to be) to understand quantitatively the effects of process history on functional properties. These relationships were assessed via studies on Nb samples and cavity parts, which had various combinations of forming processes, welding, heat treatments, and surface preparation. A primary focus was on large-grain cavity building strategies. Effects of processing operations and exposure to hydrogen on the thermal conductivity has been identified in single and bi-crystal samples, showing that the thermal conductivity can be altered by a factor of 5 depending on process history. Characterization of single crystal tensile samples show a strong effect of crystal orientation on deformation resistance and shape changes. Large grain half cells were examined to characterize defect content and surface damage effects, which provided quantitative information about the depth damage layers from forming.

  13. Clearance of protoporphyrin IX induced by 5-aminolevulinic acid from WiDr human colon carcinoma cells

    NASA Astrophysics Data System (ADS)

    Juzeniene, Asta; Kaliszewski, Miron; Bugaj, Andrzej; Moan, Johan

    2009-06-01

    5-aminolevulinic acid-mediated photodynamic therapy (ALA-PDT) is the most widely practiced form of PDT in dermatology. One of the advantages of ALA-PDT is that undesirable photosensitization lasts only for 24-48 h. In order to optimize ALA-PDT it is necessary to understand the mechanisms controlling intracellular PpIX clearance (efflux and transformation into heme) in order to decrease protoporphyrin IX (PpIX) clearance rates in the early stages of its production. The aim of this study was to investigate the factors controlling the clearance of intracellular PpIX. Fluorescence spectroscopy was used to study PpIX kinetics in WiDr cells initially treated with ALA. The clearance rate of PpIX in WiDr cells was faster after application of a low concentration of ALA (0.1 mM) than after application of high concentration of ALA (1 mM). PpIX was cleared faster from cells which initially were seeded at low densities than cells seeded at higher densities. The presence of the iron chelator deferoxamine reduced the clearance rate of PpIX, while the presence of ferrous sulfate acted oppositely. The decay rate of PpIX in WiDr cells was faster at higher temperature than at lower. The ferrochelatase activity at pH 7.2 was significantly greater than that at pH 6.7. ALA concentration, application time, cell density, temperature, pH, intracellular iron content, intracellular amount and localization of PpIX are factors controlling PpIX clearance.

  14. Induction by hypoxia combined with low glucose or low bicarbonate and high posttranslational stability upon reoxygenation contribute to carbonic anhydrase IX expression in cancer cells.

    PubMed

    Rafajová, Monika; Zatovicová, Miriam; Kettmann, Richard; Pastorek, Jaromír; Pastoreková, Silvia

    2004-04-01

    Hypoxia is an important factor of tumor microenvironment that significantly influences behaviour of tumor cells via activation of genes whose products are involved in adaptation to hypoxic stress, such as vascular endothelial growth factor (VEGF) and glucose transporter (GLUT-1). Carbonic anhydrase IX (CA IX) is one of the most strongly hypoxia-inducible proteins with potential value as an intrinsic marker of hypoxia. However, intratumoral distribution of CA IX only partially overlaps with distribution of VEGF and GLUT-1 indicating that regulation of CA IX differs from the regulation of other hypoxic markers. Therefore, we analysed CA IX expression in response to hypoxia combined with other stresses, and determined the stability of CA IX protein upon reoxygenation using HeLa cells as a model. We found that both hypoxia-induced transcription and CA IX protein level are further increased by reduced glucose or bicarbonate concentrations. Post-translational stability of CA IX was assessed by monitoring the quantity of biotinylated protein extracted at different time points from the cells labelled immediately after shift to reoxygenation. CA IX protein half-life in reoxygenated cells was 38 h and was independent of the duration of the foregoing hypoxia. This finding has potential implications for interpretation of clinical data as it suggests that CA IX expression may detect not only actually hypoxic tumor regions, but also the regions affected by hypoxia and adverse microenvironmental stresses before biopsy or tumor removal.

  15. Employing a Gain-of-Function Factor IX Variant R338L to Advance the Efficacy and Safety of Hemophilia B Human Gene Therapy: Preclinical Evaluation Supporting an Ongoing Adeno-Associated Virus Clinical Trial

    PubMed Central

    Sun, Junjiang; Gui, Tong; Hu, Genlin; Hannah, William B.; Wichlan, David G.; Wu, Zhijian; Grieger, Joshua C.; Li, Chengwen; Suwanmanee, Thipparat; Stafford, Darrel W.; Booth, Carmen J.; Samulski, Jade J.; Kafri, Tal; McPhee, Scott W.J.

    2015-01-01

    Abstract Vector capsid dose-dependent inflammation of transduced liver has limited the ability of adeno-associated virus (AAV) factor IX (FIX) gene therapy vectors to reliably convert severe to mild hemophilia B in human clinical trials. These trials also identified the need to understand AAV neutralizing antibodies and empty AAV capsids regarding their impact on clinical success. To address these safety concerns, we have used a scalable manufacturing process to produce GMP-grade AAV8 expressing the FIXR338L gain-of-function variant with minimal (<10%) empty capsid and have performed comprehensive dose–response, biodistribution, and safety evaluations in clinically relevant hemophilia models. The scAAV8.FIXR338L vector produced greater than 6-fold increased FIX specific activity compared with wild-type FIX and demonstrated linear dose responses from doses that produced 2–500% FIX activity, associated with dose-dependent hemostasis in a tail transection bleeding challenge. More importantly, using a bleeding model that closely mimics the clinical morbidity of hemophilic arthropathy, mice that received the scAAV8.FIXR338L vector developed minimal histopathological findings of synovitis after hemarthrosis, when compared with mice that received identical doses of wild-type FIX vector. Hemostatically normal mice (n=20) and hemophilic mice (n=88) developed no FIX antibodies after peripheral intravenous vector delivery. No CD8+ T cell liver infiltrates were observed, despite the marked tropism of scAAV8.FIXR338L for the liver in a comprehensive biodistribution evaluation (n=60 animals). With respect to the role of empty capsids, we demonstrated that in vivo FIXR338L expression was not influenced by the presence of empty AAV particles, either in the presence or absence of various titers of AAV8-neutralizing antibodies. Necropsy of FIX–/– mice 8–10 months after vector delivery revealed no microvascular or macrovascular thrombosis in mice expressing FIXR338L (plasma

  16. Employing a gain-of-function factor IX variant R338L to advance the efficacy and safety of hemophilia B human gene therapy: preclinical evaluation supporting an ongoing adeno-associated virus clinical trial.

    PubMed

    Monahan, Paul E; Sun, Junjiang; Gui, Tong; Hu, Genlin; Hannah, William B; Wichlan, David G; Wu, Zhijian; Grieger, Joshua C; Li, Chengwen; Suwanmanee, Thipparat; Stafford, Darrel W; Booth, Carmen J; Samulski, Jade J; Kafri, Tal; McPhee, Scott W J; Samulski, R Jude

    2015-02-01

    Vector capsid dose-dependent inflammation of transduced liver has limited the ability of adeno-associated virus (AAV) factor IX (FIX) gene therapy vectors to reliably convert severe to mild hemophilia B in human clinical trials. These trials also identified the need to understand AAV neutralizing antibodies and empty AAV capsids regarding their impact on clinical success. To address these safety concerns, we have used a scalable manufacturing process to produce GMP-grade AAV8 expressing the FIXR338L gain-of-function variant with minimal (<10%) empty capsid and have performed comprehensive dose-response, biodistribution, and safety evaluations in clinically relevant hemophilia models. The scAAV8.FIXR338L vector produced greater than 6-fold increased FIX specific activity compared with wild-type FIX and demonstrated linear dose responses from doses that produced 2-500% FIX activity, associated with dose-dependent hemostasis in a tail transection bleeding challenge. More importantly, using a bleeding model that closely mimics the clinical morbidity of hemophilic arthropathy, mice that received the scAAV8.FIXR338L vector developed minimal histopathological findings of synovitis after hemarthrosis, when compared with mice that received identical doses of wild-type FIX vector. Hemostatically normal mice (n=20) and hemophilic mice (n=88) developed no FIX antibodies after peripheral intravenous vector delivery. No CD8(+) T cell liver infiltrates were observed, despite the marked tropism of scAAV8.FIXR338L for the liver in a comprehensive biodistribution evaluation (n=60 animals). With respect to the role of empty capsids, we demonstrated that in vivo FIXR338L expression was not influenced by the presence of empty AAV particles, either in the presence or absence of various titers of AAV8-neutralizing antibodies. Necropsy of FIX(-/-) mice 8-10 months after vector delivery revealed no microvascular or macrovascular thrombosis in mice expressing FIXR338L (plasma FIX activity

  17. Comparative effectiveness of clinically used light sources for cutaneous protoporphyrin IX-based photodynamic therapy.

    PubMed

    Sayre, Robert M; Dowdy, John C; Gottschalk, Ronald W

    2011-04-01

    This report documents the optical characteristics of a number of photodynamic therapy (PDT) light sources of varied types, measured and indexed relative to estimated effectiveness for activation of the PDT chromaphore protoporphyrin IX (PpIX). PDT sources in use at several clinics, including intense pulsed light (IPL) sources, lasers, and continuous wave (CW) light sources, were spectroradiometrically measured and indexed relative to their overlap to an absorption spectrum of PpIX. The sources were highly disparate, varying in power from irradiance in the mW/cm(2) range for the CW sources up to ∼30 J/cm(2) per flash for the IPL sources. Our PpIX Index ranged by a factor of nearly 100 (0.008-0.630) in estimated PpIX PDT effectiveness following the distinct spectral characteristics of the light sources surveyed. Application of this PpIX Index, tempered with an understanding of the biology of the lesion being treated and effective spectrum of the light source reaching the lesion requiring therapy, provides a rational algorithm to approximate equivalent light doses prior to clinical protocols to establish equivalent patient outcomes employing alternative PDT light sources.

  18. Identification of a juxtamembrane mechanosensitive domain in the platelet mechanosensor glycoprotein Ib-IX complex

    PubMed Central

    Zhang, Wei; Deng, Wei; Zhou, Liang; Xu, Yan; Yang, Wenjun; Liang, Xin; Wang, Yizhen; Kulman, John D.; Zhang, X. Frank

    2015-01-01

    How glycoprotein (GP)Ib-IX complex on the platelet surface senses the blood flow through its binding to the plasma protein von Willebrand factor (VWF) and transmits a signal into the platelet remains unclear. Here we show that optical tweezer-controlled pulling of the A1 domain of VWF (VWF-A1) on GPIb-IX captured by its cytoplasmic domain induced unfolding of a hitherto unidentified structural domain before the dissociation of VWF-A1 from GPIb-IX. Additional studies using recombinant proteins and mutant complexes confirmed its existence in GPIb-IX and enabled localization of this quasi-stable mechanosensitive domain of ∼60 residues between the macroglycopeptide region and the transmembrane helix of the GPIbα subunit. These results suggest that VWF-mediated pulling under fluid shear induces unfolding of the mechanosensitive domain in GPIb-IX, which may possibly contribute to platelet mechanosensing and/or shear resistance of VWF-platelet interaction. The identification of the mechanosensitive domain in GPIb-IX has significant implications for the pathogenesis and treatment of related blood diseases. PMID:25359992

  19. Spectral action for Bianchi type-IX cosmological models

    NASA Astrophysics Data System (ADS)

    Fan, Wentao; Fathizadeh, Farzad; Marcolli, Matilde

    2015-10-01

    A rationality result previously proved for Robertson-Walker metrics is extended to a homogeneous anisotropic cosmological model, namely the Bianchi type-IX minisuperspace. It is shown that the Seeley-de Witt coefficients appearing in the expansion of the spectral action for the Bianchi type-IX geometry are expressed in terms of polynomials with rational coefficients in the cosmic evolution factors w 1( t) , w 2( t) , w 3( t) , and their higher derivates with respect to time. We begin with the computation of the Dirac operator of this geometry and calculate the coefficients a 0 ,a 2 ,a 4 of the spectral action by using heat kernel methods and parametric pseudodifferential calculus. An efficient method is devised for computing the Seeley-de Witt coefficients of a geometry by making use of Wodzicki's noncommutative residue, and it is confirmed that the method checks out for the cosmological model studied in this article. The advantages of the new method are discussed, which combined with symmetries of the Bianchi type-IX metric, yield an elegant proof of the rationality result.

  20. A method for high purity intestinal epithelial cell culture from adult human and murine tissues for the investigation of innate immune function.

    PubMed

    Graves, Christina L; Harden, Scott W; LaPato, Melissa; Nelson, Michael; Amador, Byron; Sorenson, Heather; Frazier, Charles J; Wallet, Shannon M

    2014-12-01

    Intestinal epithelial cells (IECs) serve as an important physiologic barrier between environmental antigens and the host intestinal immune system. Thus, IECs serve as a first line of defense and may act as sentinel cells during inflammatory insults. Despite recent renewed interest in IEC contributions to host immune function, the study of primary IEC has been hindered by lack of a robust culture technique, particularly for small intestinal and adult tissues. Here, a novel adaptation for culture of primary IEC is described for human duodenal organ donor tissue as well as duodenum and colon of adult mice. These epithelial cell cultures display characteristic phenotypes and are of high purity. In addition, the innate immune function of human primary IEC, specifically with regard to Toll-like receptor (TLR) expression and microbial ligand responsiveness, is contrasted with a commonly used intestinal epithelial cell line (HT-29). Specifically, TLR expression at the mRNA level and production of cytokine (IFNγ and TNFα) in response to TLR agonist stimulation is assessed. Differential expression of TLRs as well as innate immune responses to ligand stimulation is observed in human-derived cultures compared to that of HT-29. Thus, use of this adapted method to culture primary epithelial cells from adult human donors and from adult mice will allow for more appropriate studies of IECs as innate immune effectors.

  1. Microfluidic device with integrated microfilter of conical-shaped holes for high efficiency and high purity capture of circulating tumor cells.

    PubMed

    Tang, Yadong; Shi, Jian; Li, Sisi; Wang, Li; Cayre, Yvon E; Chen, Yong

    2014-08-13

    Capture of circulating tumor cells (CTCs) from peripheral blood of cancer patients has major implications for metastatic detection and therapy analyses. Here we demonstrated a microfluidic device for high efficiency and high purity capture of CTCs. The key novelty of this approach lies on the integration of a microfilter with conical-shaped holes and a micro-injector with cross-flow components for size dependent capture of tumor cells without significant retention of non-tumor cells. Under conditions of constant flow rate, tumor cells spiked into phosphate buffered saline could be recovered and then cultured for further analyses. When tumor cells were spiked in blood of healthy donors, they could also be recovered at high efficiency and high clearance efficiency of white blood cells. When the same device was used for clinical validation, CTCs could be detected in blood samples of cancer patients but not in that of healthy donors. Finally, the capture efficiency of tumor cells is cell-type dependent but the hole size of the filter should be more closely correlated to the nuclei size of the tumor cells. Together with the advantage of easy operation, low-cost and high potential of integration, this approach offers unprecedented opportunities for metastatic detection and cancer treatment monitoring.

  2. In vitro and in vivo studies on the degradation of high-purity Mg (99.99wt.%) screw with femoral intracondylar fractured rabbit model.

    PubMed

    Han, Pei; Cheng, Pengfei; Zhang, Shaoxiang; Zhao, Changli; Ni, Jiahua; Zhang, Yuanzhuang; Zhong, Wanrun; Hou, Peng; Zhang, Xiaonong; Zheng, Yufeng; Chai, Yimin

    2015-09-01

    High-purity magnesium (HP Mg) takes advantage in no alloying toxic elements and slower degradation rate in lack of second phases and micro-galvanic corrosion. In this study, as rolled HP Mg was fabricated into screws and went through in vitro immersion tests, cytotoxicity test and bioactive analysis. The HP Mg screws performed uniform corrosion behavior in vitro, and its extraction promoted cell viability, bone alkaline phosphatase (ALP) activity, and mRNA expression of osteogenic differentiation related gene, i.e. ALP, osteopontin (OPN) and RUNX2 of human bone marrow mesenchymal stem cells (hBMSCs). Then HP Mg screws were implanted in vivo as load-bearing implant to fix bone fracture and subsequently gross observation, range of motion (ROM), X-ray scanning, qualitative micro-computed tomography (μCT) analysis, histological analysis, bending-force test and SEM morphology of retrieved screws were performed respectively at 4, 8, 16 and 24 weeks. As a result, the retrieved HP Mg screws in fixation of rabbit femoral intracondylar fracture showed uniform degradation morphology and enough bending force. However, part of PLLA screws was broken in bolt, although its screw thread was still intact. Good osseointegration was revealed surrounding HP Mg screws and increased bone volume and bone mineral density were detected at fracture gap, indicating the rigid fixation and enhanced fracture healing process provided by HP Mg screws. Consequently, the HP Mg showed great potential as internal fixation devices in intra-articular fracture operation.

  3. Influence of impurity elements on the nucleation and growth of Si in high purity melt-spun Al-Si-based alloys

    NASA Astrophysics Data System (ADS)

    Li, J. H.; Zarif, M. Z.; Dehm, G.; Schumacher, P.

    2012-11-01

    The nucleation and growth of Si has been investigated by TEM in a series of high purity melt spun Al-5Si (wt%)-based alloys with a trace addition of Fe and Sr. In the as-melt-spun condition, some twinned Si particles were found to form directly from the liquid along the grain boundary. The addition of Sr into Al-5Si-based alloys promotes the twinning of Si particles on the grain boundary and the formation of Si precipitates in the α-Al matrix. The majority of plate-shaped and truncated pyramid-shaped Si precipitates were also found to nucleate and grow along {111}α-Al planes from supersaturated solid solution in the α-Al matrix. In contrast, controlled slow cooling decreased the amount of Si precipitates, while the size of the Si precipitates increased. The orientation relationship between these Si precipitates and the α-Al matrix still remained cube to cube. The β-Al5FeSi intermetallic was also observed, depending on subsequent controlled cooling.

  4. Robust Low-Cost Water-Gas Shift Membrane Reactor for High-Purity Hydrogen Production form Coal-Derived Syngas

    SciTech Connect

    James Torkelson; Neng Ye; Zhijiang Li; Decio Coutinho; Mark Fokema

    2008-05-31

    This report details work performed in an effort to develop a low-cost, robust water gas shift membrane reactor to convert coal-derived syngas into high purity hydrogen. A sulfur- and halide-tolerant water gas shift catalyst and a sulfur-tolerant dense metallic hydrogen-permeable membrane were developed. The materials were integrated into a water gas shift membrane reactor in order to demonstrate the production of >99.97% pure hydrogen from a simulated coal-derived syngas stream containing 2000 ppm hydrogen sulfide. The objectives of the program were to (1) develop a contaminant-tolerant water gas shift catalyst that is able to achieve equilibrium carbon monoxide conversion at high space velocity and low steam to carbon monoxide ratio, (2) develop a contaminant-tolerant hydrogen-permeable membrane with a higher permeability than palladium, (3) demonstrate 1 L/h purified hydrogen production from coal-derived syngas in an integrated catalytic membrane reactor, and (4) conduct a cost analysis of the developed technology.

  5. Microfluidic device with integrated microfilter of conical-shaped holes for high efficiency and high purity capture of circulating tumor cells

    NASA Astrophysics Data System (ADS)

    Tang, Yadong; Shi, Jian; Li, Sisi; Wang, Li; Cayre, Yvon E.; Chen, Yong

    2014-08-01

    Capture of circulating tumor cells (CTCs) from peripheral blood of cancer patients has major implications for metastatic detection and therapy analyses. Here we demonstrated a microfluidic device for high efficiency and high purity capture of CTCs. The key novelty of this approach lies on the integration of a microfilter with conical-shaped holes and a micro-injector with cross-flow components for size dependent capture of tumor cells without significant retention of non-tumor cells. Under conditions of constant flow rate, tumor cells spiked into phosphate buffered saline could be recovered and then cultured for further analyses. When tumor cells were spiked in blood of healthy donors, they could also be recovered at high efficiency and high clearance efficiency of white blood cells. When the same device was used for clinical validation, CTCs could be detected in blood samples of cancer patients but not in that of healthy donors. Finally, the capture efficiency of tumor cells is cell-type dependent but the hole size of the filter should be more closely correlated to the nuclei size of the tumor cells. Together with the advantage of easy operation, low-cost and high potential of integration, this approach offers unprecedented opportunities for metastatic detection and cancer treatment monitoring.

  6. Separation of high-purity syringol and acetosyringone from rice straw-derived bio-oil by combining the basification-acidification process and column chromatography.

    PubMed

    Hao, Shilai; Chen, Kaifei; Cao, Leichang; Zhu, Xiangdong; Luo, Gang; Zhang, Shicheng; Chen, Jianmin

    2016-10-01

    Numerous technologies have been used to reclaim valuable chemicals from bio-oil. In this study, a combination of the basification-acidification process and column chromatography was employed for the separation of high-purity syringol and acetosyringone from rice straw-derived bio-oil. The optimal conditions for the basification-acidification process and the possible precipitation mechanism of the basification were explored. The results showed the following as the optimal conditions for the basification process: mass ratio of calcium hydroxide (Ca(OH)2 ) to bio-oil, 2.0; reaction temperature, 70°C; and reaction time, 30 min. The results also showed that 1.6 mol of hydrochloric acid (HCl) per gram of bio-oil was optimal for the acidification. The precipitation was found to proceed via a possible mechanism involving the reaction of the phenolic compounds in the bio-oil with Ca(OH)2 to produce a precipitate. After further separation by column chromatography, purities of 91.4 and 96.2% (from gas chromatography-mass spectrometry) were obtained for syringol and acetosyringone, respectively. Their recoveries for the whole process were 73.0 and 39.3%, respectively.

  7. Thermoluminescence (TL) properties and x-ray diffraction (XRD) analysis of high purity CaSO{sub 4}:Dy TL material

    SciTech Connect

    Kamarudin, Nadira; Abdullah, Wan Saffiey Wan; Dollah, Mohd Taufik; Hamid, Muhammad Azmi Abdul

    2014-09-03

    This paper presents the characterization and TL properties of dysprosium (Dy) doped calcium sulfate (CaSO{sub 4}) TL material produced by co-precipitation technique with 0.5mol% concentration of dopant. The morphology of the produced TL material was studied using scanning electron microscope (SEM) and the micrograph shows that rectangular parallelepiped shaped crystal with the average of 150 μm in length were produced. The crystallinity of the produced powder was studied using x-ray powder diffraction (XRD). The XRD spectra show that the TL material produced is high purity anhydrite CaSO{sub 4} with average crystallite size of 74 nm with orthorhombic crystal system. The TL behavior of produced CaSO{sub 4}:Dy was studied using a TLD reader after exposure to gamma ray by Co{sup 60} source with the doses of 1,5 and 10 Gy. The glow curve shows linear response with glow peak around 230°C which is desired development in the field of radiation dosimetry.

  8. El Titulo IX y La Discriminacion por Sexo (Title IX and Sex Discrimination).

    ERIC Educational Resources Information Center

    Office for Civil Rights (ED), Washington, DC.

    Title IX of the Education Amendments of 1972 protects people from discrimination based on sex in education programs or activities that receive Federal financial assistance. This brochure outlines the responsibilities of education programs and activities covered by Title IX, the responsibilities of the Office for Civil Rights (OCR) in enforcing…

  9. 45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... policy, ; 86.9 Distribution, 86.9(c) Notification of policy, ; 86.9(a) Publications, 86.9(b) Dress codes... 45 Public Welfare 1 2010-10-01 2010-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare DEPARTMENT OF HEALTH...

  10. 34 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Distribution, 106.9(c) Notification of policy, ; 106.9(a) Publications, 106.9(b) Dress codes 106.31(b) (4) E... 34 Education 1 2010-07-01 2010-07-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Education Regulations of the Offices of...

  11. Microstructures and superconducting properties of high performance MgB2 thin films deposited from a high-purity, dense Mg-B target

    PubMed Central

    Li, G.Z.; Susner, M.A.; Bohnenstiehl, S.D.; Sumption, M.D.; Collings, E.W.

    2015-01-01

    High quality, c-axis oriented, MgB2 thin films were successfully grown on 6H-SiC substrates using pulsed laser deposition (PLD) with subsequent in situ annealing. To obtain high purity films free from oxygen contamination, a dense Mg-B target was specially made from a high temperature, high pressure reaction of Mg and B to form large-grained (10~50 µm) MgB2. Microstructural analysis via electron microscopy found that the resulting grains of the film were composed of ultrafine columnar grains of 19–30 nm. XRD analysis showed the MgB2 films to be c-axis oriented; the a-axis and c-axis lattice parameters were determined to be 3.073 ± 0.005 Å and 3.528 ± 0.010 Å, respectively. The superconducting critical temperature, Tc,onset, increased monotonically as the annealing temperature was increased, varying from 25.2 K to 33.7 K. The superconducting critical current density as determined from magnetic measurements, Jcm, at 5 K, was 105 A/cm2 at 7.8 T; at 20 K, 105 A/cm2 was reached at 3.1 T. The transport and pinning properties of these films were compared to “powder-in-tube” (PIT) and “internal-infiltration” (AIMI) processed wires. Additionally, examination of the pinning mechanism showed that when scaled to the peak in the pinning curve, the films follow the grain boundary, or surface, pinning mechanism quite well, and are similar to the response seen for C doped PIT and AIMI strands, in contrast to the behavior seen in undoped PIT wires, in which deviations are seen at high b (b = B/Bc2). On the other hand, the magnitude of the pinning force was similar for the thin films and AIMI conductors, unlike the values from connectivity-suppressed PIT strands. PMID:26417117

  12. Neutron Damage in Mechanically-Cooled High-Purity Germanium Detectors for Field-Portable Prompt Gamma Neutron Activation Analysis (PGNAA) Systems

    SciTech Connect

    E.H. Seabury; C.J. Wharton; A.J. Caffrey; J.B. McCabe; C. DeW. Van Siclen

    2013-10-01

    Prompt Gamma Neutron Activation (PGNAA) systems require the use of a gamma-ray spectrometer to record the gamma-ray spectrum of an object under test and allow the determination of the object’s composition. Field-portable systems, such as Idaho National Laboratory’s PINS system, have used standard liquid-nitrogen-cooled high-purity germanium (HPGe) detectors to perform this function. These detectors have performed very well in the past, but the requirement of liquid-nitrogen cooling limits their use to areas where liquid nitrogen is readily available or produced on-site. Also, having a relatively large volume of liquid nitrogen close to the detector can impact some assessments, possibly leading to a false detection of explosives or other nitrogen-containing chemical. Use of a mechanically-cooled HPGe detector is therefore very attractive for PGNAA applications where nitrogen detection is critical or where liquid-nitrogen logistics are problematic. Mechanically-cooled HPGe detectors constructed from p-type germanium, such as Ortec’s trans-SPEC, have been commercially available for several years. In order to assess whether these detectors would be suitable for use in a fielded PGNAA system, Idaho National Laboratory (INL) has been performing a number of tests of the resistance of mechanically-cooled HPGe detectors to neutron damage. These detectors have been standard commercially-available p-type HPGe detectors as well as prototype n-type HPGe detectors. These tests compare the performance of these different detector types as a function of crystal temperature and incident neutron fluence on the crystal.

  13. High temperature annealing effects on deep-level defects in a high purity semi-insulating 4H-SiC substrate

    NASA Astrophysics Data System (ADS)

    Iwamoto, Naoya; Azarov, Alexander; Ohshima, Takeshi; Moe, Anne Marie M.; Svensson, Bengt G.

    2015-07-01

    Effects of high-temperature annealing on deep-level defects in a high-purity semi-insulating 4H silicon carbide substrate have been studied by employing current-voltage, capacitance-voltage, junction spectroscopy, and chemical impurity analysis measurements. Secondary ion mass spectrometry data reveal that the substrate contains boron with concentration in the mid 1015 cm-3 range, while other impurities including nitrogen, aluminum, titanium, vanadium and chromium are below their detection limits (typically ˜1014 cm-3). Schottky barrier diodes fabricated on substrates annealed at 1400-1700 °C exhibit metal/p-type semiconductor behavior with a current rectification of up to 8 orders of magnitude at bias voltages of ±3 V. With increasing annealing temperature, the series resistance of the Schottky barrier diodes decreases, and the net acceptor concentration in the substrates increases approaching the chemical boron content. Admittance spectroscopy results unveil the presence of shallow boron acceptors and deep-level defects with levels in lower half of the bandgap. After the 1400 °C annealing, the boron acceptor still remains strongly compensated at room temperature by deep donor-like levels located close to mid-gap. However, the latter decrease in concentration with increasing annealing temperature and after 1700 °C, the boron acceptor is essentially uncompensated. Hence, the deep donors are decisive for the semi-insulating properties of the substrates, and their thermal evolution limits the thermal budget for device processing. The origin of the deep donors is not well-established, but substantial evidence supporting an assignment to carbon vacancies is presented.

  14. High temperature annealing effects on deep-level defects in a high purity semi-insulating 4H-SiC substrate

    SciTech Connect

    Iwamoto, Naoya Azarov, Alexander; Svensson, Bengt G.; Ohshima, Takeshi; Moe, Anne Marie M.

    2015-07-28

    Effects of high-temperature annealing on deep-level defects in a high-purity semi-insulating 4H silicon carbide substrate have been studied by employing current-voltage, capacitance-voltage, junction spectroscopy, and chemical impurity analysis measurements. Secondary ion mass spectrometry data reveal that the substrate contains boron with concentration in the mid 10{sup 15 }cm{sup −3} range, while other impurities including nitrogen, aluminum, titanium, vanadium and chromium are below their detection limits (typically ∼10{sup 14 }cm{sup −3}). Schottky barrier diodes fabricated on substrates annealed at 1400–1700 °C exhibit metal/p-type semiconductor behavior with a current rectification of up to 8 orders of magnitude at bias voltages of ±3 V. With increasing annealing temperature, the series resistance of the Schottky barrier diodes decreases, and the net acceptor concentration in the substrates increases approaching the chemical boron content. Admittance spectroscopy results unveil the presence of shallow boron acceptors and deep-level defects with levels in lower half of the bandgap. After the 1400 °C annealing, the boron acceptor still remains strongly compensated at room temperature by deep donor-like levels located close to mid-gap. However, the latter decrease in concentration with increasing annealing temperature and after 1700 °C, the boron acceptor is essentially uncompensated. Hence, the deep donors are decisive for the semi-insulating properties of the substrates, and their thermal evolution limits the thermal budget for device processing. The origin of the deep donors is not well-established, but substantial evidence supporting an assignment to carbon vacancies is presented.

  15. Preparation of High Purity, High Molecular-Weight Chitin from Ionic Liquids for Use as an Adsorbate for the Extraction of Uranium from Seawater

    SciTech Connect

    Rogers, Robin

    2013-12-21

    Ensuring a domestic supply of uranium is a key issue facing the wider implementation of nuclear power. Uranium is mostly mined in Kazakhstan, Australia, and Canada, and there are few high-grade uranium reserves left worldwide. Therefore, one of the most appealing potential sources of uranium is the vast quantity dissolved in the oceans (estimated to be 4.4 billion tons worldwide). There have been research efforts centered on finding a means to extract uranium from seawater for decades, but so far none have resulted in an economically viable product, due in part to the fact that the materials that have been successfully demonstrated to date are too costly (in terms of money and energy) to produce on the necessary scale. Ionic Liquids (salts which melt below 100{degrees}C) can completely dissolve raw crustacean shells, leading to recovery of a high purity, high molecular weight chitin powder and to fibers and films which can be spun directly from the extract solution suggesting that continuous processing might be feasible. The work proposed here will utilize the unprecedented control this makes possible over the chitin fiber a) to prepare electrospun nanofibers of very high surface area and in specific architectures, b) to modify the fiber surfaces chemically with selective extractant capacity, and c) to demonstrate their utility in the direct extraction and recovery of uranium from seawater. This approach will 1) provide direct extraction of chitin from shellfish waste thus saving energy over the current industrial process for obtaining chitin; 2) allow continuous processing of nanofibers for very high surface area fibers in an economical operation; 3) provide a unique high molecular weight chitin not available from the current industrial process, leading to stronger, more durable fibers; and 4) allow easy chemical modification of the large surface areas of the fibers for appending uranyl selective functionality providing selectivity and ease of stripping. The

  16. Diagnostics method for the rapid quantitative detection and identification of low-level contamination of high-purity water with pathogenic bacteria.

    PubMed

    Minogue, Elizabeth; Reddington, Kate; Dorai-Raj, Siobhan; Tuite, Nina; Clancy, Eoin; Barry, Thomas

    2013-09-01

    High-purity water (HPW) can be contaminated with pathogenic microorganisms, which may result in human infection. Current culture-based techniques for the detection of microorganisms from HPW can be slow and laborious. The aim of this study was to develop a rapid method for the quantitative detection and identification of pathogenic bacteria causing low-level contamination of HPW. A novel internally controlled multiplex real-time PCR diagnostics assay was designed and optimized to specifically detect and identify Pseudomonas aeruginosa and the Burkholderia genus. Sterile HPW, spiked with a bacterial load ranging from 10 to 10(3) cfu/100 ml, was filtered and the bacterial cells were removed from the filters by sonication. Total genomic DNA was then purified from these bacteria and subjected to testing with the developed novel multiplex real-time PCR diagnostics assay. The specific P. aeruginosa and Burkholderia genus assays have an analytical sensitivity of 3.5 genome equivalents (GE) and 3.7 GE, respectively. This analysis demonstrated that it was possible to detect a spiked bacterial load of 1.06 × 10(2) cfu/100 ml for P. aeruginosa and 2.66 × 10(2) cfu/100 ml for B. cepacia from a 200-ml filtered HPW sample. The rapid diagnostics method described can reliably detect, identify, and quantify low-level contamination of HPW with P. aeruginosa and the Burkholderia genus in <4 h. We propose that this rapid diagnostics method could be applied to the pharmaceutical and clinical sectors to assure the safety and quality of HPW, medical devices, and patient-care equipment.

  17. Microstructures and superconducting properties of high performance MgB2 thin films deposited from a high-purity, dense Mg-B target.

    PubMed

    Li, G Z; Susner, M A; Bohnenstiehl, S D; Sumption, M D; Collings, E W

    2015-12-01

    High quality, c-axis oriented, MgB2 thin films were successfully grown on 6H-SiC substrates using pulsed laser deposition (PLD) with subsequent in situ annealing. To obtain high purity films free from oxygen contamination, a dense Mg-B target was specially made from a high temperature, high pressure reaction of Mg and B to form large-grained (10~50 µm) MgB2. Microstructural analysis via electron microscopy found that the resulting grains of the film were composed of ultrafine columnar grains of 19-30 nm. XRD analysis showed the MgB2 films to be c-axis oriented; the a-axis and c-axis lattice parameters were determined to be 3.073 ± 0.005 Å and 3.528 ± 0.010 Å, respectively. The superconducting critical temperature, Tc,onset , increased monotonically as the annealing temperature was increased, varying from 25.2 K to 33.7 K. The superconducting critical current density as determined from magnetic measurements, Jcm , at 5 K, was 10(5) A/cm(2) at 7.8 T; at 20 K, 10(5) A/cm(2) was reached at 3.1 T. The transport and pinning properties of these films were compared to "powder-in-tube" (PIT) and "internal-infiltration" (AIMI) processed wires. Additionally, examination of the pinning mechanism showed that when scaled to the peak in the pinning curve, the films follow the grain boundary, or surface, pinning mechanism quite well, and are similar to the response seen for C doped PIT and AIMI strands, in contrast to the behavior seen in undoped PIT wires, in which deviations are seen at high b (b = B/Bc2 ). On the other hand, the magnitude of the pinning force was similar for the thin films and AIMI conductors, unlike the values from connectivity-suppressed PIT strands.

  18. Quantum supersymmetric Bianchi IX cosmology

    NASA Astrophysics Data System (ADS)

    Damour, Thibault; Spindel, Philippe

    2014-11-01

    We study the quantum dynamics of a supersymmetric squashed three-sphere by dimensionally reducing (to one timelike dimension) the action of D =4 simple supergravity for a S U (2 ) -homogeneous (Bianchi IX) cosmological model. The quantization of the homogeneous gravitino field leads to a 64-dimensional fermionic Hilbert space. After imposition of the diffeomorphism constraints, the wave function of the Universe becomes a 64-component spinor of spin(8,4) depending on the three squashing parameters, which satisfies Dirac-like, and Klein-Gordon-like, wave equations describing the propagation of a "quantum spinning particle" reflecting off spin-dependent potential walls. The algebra of the supersymmetry constraints and of the Hamiltonian one is found to close. One finds that the quantum Hamiltonian is built from operators that generate a 64-dimensional representation of the (infinite-dimensional) maximally compact subalgebra of the rank-3 hyperbolic Kac-Moody algebra A E3 . The (quartic-in-fermions) squared-mass term μ^ 2 entering the Klein-Gordon-like equation has several remarkable properties: (i) it commutes with all the other (Kac-Moody-related) building blocks of the Hamiltonian; (ii) it is a quadratic function of the fermion number NF; and (iii) it is negative in most of the Hilbert space. The latter property leads to a possible quantum avoidance of the singularity ("cosmological bounce"), and suggests imposing the boundary condition that the wave function of the Universe vanish when the volume of space tends to zero (a type of boundary condition which looks like a final-state condition when considering the big crunch inside a black hole). The space of solutions is a mixture of "discrete-spectrum states" (parametrized by a few constant parameters, and known in explicit form) and of continuous-spectrum states (parametrized by arbitrary functions entering some initial-value problem). The predominantly negative values of the squared-mass term lead to a "bottle

  19. 77 FR 64401 - Order of Succession for HUD Region IX

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-19

    ... URBAN DEVELOPMENT Order of Succession for HUD Region IX AGENCY: Office of Field Policy and Management... Succession for the San Francisco Regional Office and its Field Offices (Region IX). This Order of Succession supersedes all previous Orders of Succession for HUD Region IX. DATES: Effective Date: October 9, 2012....

  20. The Restoration of Title IX: Implications for Higher Education.

    ERIC Educational Resources Information Center

    Sandler, Bernice R.

    This booklet helps institutions understand the restoration of Title IX of the Education Amendments of 1972 and changes resulting from the Civil Rights Restoration Act. Title IX prohibits sex discrimination in federally assisted education programs. A 1984 ruling held that Title IX covers only programs or activities funded with federal money. In…

  1. Title IX: With New Opportunities, Girls' Interest Rises

    ERIC Educational Resources Information Center

    Toporek, Bryan

    2012-01-01

    On June 23, 1972, President Richard M. Nixon signed into law Title IX of the Education Amendments of 1972, which prohibits gender discrimination in any federally financed education program or activity. Title IX is far-reaching, but the law is most often associated with school and college athletics. Title IX allows schools to prove their athletic…

  2. Couples Magnetic and Structural Transitions in High-Purity Dy and Gd5SbxGe4-x

    SciTech Connect

    Chernyshov, Alexander S.

    2006-01-01

    Magnetic materials exhibiting magnetic phase transitions simultaneously with structural rearrangements of their crystal lattices hold a promise for numerous applications including magnetic refrigeration, magnetomechanical devices and sensors. We undertook a detailed study of a single crystal of dysprosium metal, which is a classical example of a system where magnetic and crystallographic sublattices can be either coupled or decoupled from one another. Magnetocaloric effect, magnetization, ac magnetic susceptibility, and heat capacity of high purity single crystals of dysprosium have been investigated over broad temperature and magnetic field intervals with the magnetic field vector parallel to either the a- or c-axes of the crystal. Notable differences in the behavior of the physical properties when compared to Dy samples studied in the past have been observed between 110 K and 125 K, and between 178 K and ~210 K. A plausible mechanism based on the formation of antiferromagnetic clusters in the impure Dy has been suggested in order to explain the reduction of the magnetocaloric effect in the vicinity of the Neel point. Experimental and theoretical investigations of the influence of commensurability effects on the magnetic phase diagram and the value of the magnetocaloric effect have been conducted. The presence of newly found anomalies in the physical properties has been considered as evidence of previously unreported states of Dy. The refined magnetic phase diagram of dysprosium with the magnetic field vector parallel to the a-axis of a crystal has been constructed and discussed. The magnetic and crystallographic properties of Gd5SbxGe4-x pseudo-binary system were studied by x-ray diffraction (at room temperature), heat capacity, ac-magnetic susceptibility, and magnetization in the temperature interval 5-320 K in magnetic fields up to 100 kOe. The magnetic properties of three composition (x = 0.5, 1,2) were examined in detail. The

  3. The effect of environment on the creep deformation of ultra-high purity nickel-chromium-iron alloys at 360 degrees Celcius

    NASA Astrophysics Data System (ADS)

    Paraventi, Denise Jean

    2000-10-01

    Steam generators in pressurized water nuclear power plants have experienced significant problems with intergranular stress corrosion cracking (IGSCC) on the inner diameter of steam generator tubing for over 25 years. In the course of research to understand IGSCC, it has been shown that creep deformation may play a significant role in the cracking of commercial Alloy 600 (Ni-16Cr-9Fe-0.03C). The primary water environment can cause decreases in creep resistance (i.e., faster creep rates, shorter time to failure, and higher creep strains). During corrosion under the conditions of interest, both hydrogen reduction and metal dissolution occur. One or both may contribute to the enhancement of creep. The purpose of this work was to isolate the mechanism by which the water environment causes the creep deformation to increase. Activation area and activation enthalpy for glide were measured in argon and primary water on high purity Ni-16Cr-9Fe alloys. The results indicated that the activation area was reduced by primary water, consistent with a hydrogen enhanced plasticity mechanism for enhanced creep. The stress dependence of creep was also examined in argon and primary water. The results indicated that the internal stress of the alloy is reduced by the primary water environment. Lower internal stress is consistent with both a hydrogen model as well as a vacancy-aided climb model for enhanced creep. To isolate the effect of hydrogen on the creep of the alloy, experiments were conducted in a dissociated hydrogen environment. The results indicated that hydrogen would only increase the steady state creep rate if present before loading of the samples. However, if the sample was already in steady state creep and hydrogen introduced, a transient in the creep strain was observed. The creep rate returned to the original steady state rate in a short time. The results indicate that while hydrogen does affect the steady state creep to an extent, hydrogen cannot completely account for

  4. Open to All: Title IX at 30.

    ERIC Educational Resources Information Center

    Department of Education, Washington, DC. Office of the Secretary.

    This document is a report to the secretary of education on the findings of the Secretary's Commission on Opportunities in Athletics. The Commission was charged with examining Title IX. Starting in June 2002, the 15-member commission collected information, analyzed issues, and obtained broad public input directed at improving the application of…

  5. Title IX Enforcement Called 'Deeply Troubling'

    ERIC Educational Resources Information Center

    Lipka, Sara; Wolverton, Brad

    2007-01-01

    The government agency responsible for enforcing gender equity in college sports is falling down on the job, according to a report released by the National Women's Law Center. Over the past five years, the U.S. Education Department's Office for Civil Rights -- the administrative guardian of Title IX of the Education Amendments of 1972, the law that…

  6. Feminizing Science: The Alchemy of Title IX

    ERIC Educational Resources Information Center

    Hausman, Patricia

    2008-01-01

    The author scrutinizes the National Academy of Sciences report "Beyond Bias and Barriers: Fulfilling the Potential of Women in Academic Science and Engineering" and its dangerous call to place the sciences under the sledgehammer of Title IX. Her findings: A one-sided, inaccurate, and internally contradictory report prepared by a…

  7. Ares I-X Vibroacoustic Environments

    NASA Technical Reports Server (NTRS)

    Larsen, Curtis E.; Schuster, David M.; Kaufman, Daniel S.

    2009-01-01

    This paper provides a summary of the NASA Engineering and Safety Center (NESC) team recommendations and observations following participation with the Ares I-X Vibroacoustic (VA) Environments Panel in meetings at the Kennedy Space Center (KSC) and the Marshall Space Flight Center (MSFC) in March and April 2008, respectively.

  8. White light-informed optical properties improve ultrasound-guided fluorescence tomography of photoactive protoporphyrin IX

    PubMed Central

    DSouza, Alisha V.; Kanick, Stephen C.; Davis, Scott C.; Pogue, Brian W.

    2013-01-01

    Abstract. Subsurface fluorescence imaging is desirable for medical applications, including protoporphyrin-IX (PpIX)-based skin tumor diagnosis, surgical guidance, and dosimetry in photodynamic therapy. While tissue optical properties and heterogeneities make true subsurface fluorescence mapping an ill-posed problem, ultrasound-guided fluorescence-tomography (USFT) provides regional fluorescence mapping. Here USFT is implemented with spectroscopic decoupling of fluorescence signals (auto-fluorescence, PpIX, photoproducts), and white light spectroscopy-determined bulk optical properties. Segmented US images provide a priori spatial information for fluorescence reconstruction using region-based, diffuse FT. The method was tested in simulations, tissue homogeneous and inclusion phantoms, and an injected-inclusion animal model. Reconstructed fluorescence yield was linear with PpIX concentration, including the lowest concentration used, 0.025  μg/ml. White light spectroscopy informed optical properties, which improved fluorescence reconstruction accuracy compared to the use of fixed, literature-based optical properties, reduced reconstruction error and reconstructed fluorescence standard deviation by factors of 8.9 and 2.0, respectively. Recovered contrast-to-background error was 25% and 74% for inclusion phantoms without and with a 2-mm skin-like layer, respectively. Preliminary mouse-model imaging demonstrated system feasibility for subsurface fluorescence measurement in vivo. These data suggest that this implementation of USFT is capable of regional PpIX mapping in human skin tumors during photodynamic therapy, to be used in dosimetric evaluations. PMID:23584445

  9. [Fluorescence spectrum analysis system for protoporphyrin IX in serum based on wavelet transform].

    PubMed

    Zhu, Dian-ming; Yang, Hong-peng; Luo, Xiao-sen; Liu, Ying; Shen, Zhong-hua; Lu, Jian; Ni, Xiao-wu

    2007-12-01

    Protoporphyrin IX is an important kind of organic compound for vital movement, and can be used as the sign of tumour blood. Human protoporphyrin IX content in serum is very low, and affected by various factors. The serum fluorescence spectrum analysis system based on wavelet transform was used to discriminated the protoporphyrin IX weak signals. The protoporphyrin IX fluorescence spectrum was obtained by a multi-function spectrum measuring system, and decomposed several times by wavelet transform to distinguish the noise and spectrum signals. The fluorescence spectrum can be divided into corresponding discrete approximations signals (a1-a6) and discrete details signals (d1-d6) by six times of decomposition, showing the signal frequency decreasing with decomposition times increasing and the protoporphyrin IX fluorescence character peak appears here. The weak signals were discriminated and the exactly component and quantity can be acquired for further analysis. So it can be analysed quantitatively. The researches in the present paper provide the potential application in the diagnosis of incipient tumous using the serum fluorescence spectrum

  10. White light-informed optical properties improve ultrasound-guided fluorescence tomography of photoactive protoporphyrin IX

    NASA Astrophysics Data System (ADS)

    Flynn, Brendan P.; DSouza, Alisha V.; Kanick, Stephen C.; Davis, Scott C.; Pogue, Brian W.

    2013-04-01

    Subsurface fluorescence imaging is desirable for medical applications, including protoporphyrin-IX (PpIX)-based skin tumor diagnosis, surgical guidance, and dosimetry in photodynamic therapy. While tissue optical properties and heterogeneities make true subsurface fluorescence mapping an ill-posed problem, ultrasound-guided fluorescence-tomography (USFT) provides regional fluorescence mapping. Here USFT is implemented with spectroscopic decoupling of fluorescence signals (auto-fluorescence, PpIX, photoproducts), and white light spectroscopy-determined bulk optical properties. Segmented US images provide a priori spatial information for fluorescence reconstruction using region-based, diffuse FT. The method was tested in simulations, tissue homogeneous and inclusion phantoms, and an injected-inclusion animal model. Reconstructed fluorescence yield was linear with PpIX concentration, including the lowest concentration used, 0.025 μg/ml. White light spectroscopy informed optical properties, which improved fluorescence reconstruction accuracy compared to the use of fixed, literature-based optical properties, reduced reconstruction error and reconstructed fluorescence standard deviation by factors of 8.9 and 2.0, respectively. Recovered contrast-to-background error was 25% and 74% for inclusion phantoms without and with a 2-mm skin-like layer, respectively. Preliminary mouse-model imaging demonstrated system feasibility for subsurface fluorescence measurement in vivo. These data suggest that this implementation of USFT is capable of regional PpIX mapping in human skin tumors during photodynamic therapy, to be used in dosimetric evaluations.

  11. Title IX Indian Education Toolkit. A Step-by-Step Guide to the Title IX Indian Education Formula Grant.

    ERIC Educational Resources Information Center

    Beller, Floyd

    Title IX is a federal Indian Education Formula Grant Program approved in 1972 and reauthorized five times, most recently in 1994. Title IX formula grants assist groups in providing sound educational programs and opportunities for American Indian and Alaska Native students. A 1997-98 survey of Title IX grantees revealed their need for help in…

  12. Carbonic anhydrase IX, a hypoxia-induced catalytic component of the pH regulating machinery in tumors.

    PubMed

    Sedlakova, Olga; Svastova, Eliska; Takacova, Martina; Kopacek, Juraj; Pastorek, Jaromir; Pastorekova, Silvia

    2014-01-08

    Acidic tissue microenvironment contributes to tumor progression via multiple effects including the activation of angiogenic factors and proteases, reduced cell-cell adhesion, increased migration and invasion, etc. In addition, intratumoral acidosis can influence the uptake of anticancer drugs and modulate the response of tumors to conventional therapy. Acidification of the tumor microenvironment often develops due to hypoxia-triggered oncogenic metabolism, which leads to the extensive production of lactate, protons, and carbon dioxide. In order to avoid intracellular accumulation of the acidic metabolic products, which is incompatible with the survival and proliferation, tumor cells activate molecular machinery that regulates pH by driving transmembrane inside-out and outside-in ion fluxes. Carbonic anhydrase IX (CA IX) is a hypoxia-induced catalytic component of the bicarbonate import arm of this machinery. Through its catalytic activity, CA IX directly participates in many acidosis-induced features of tumor phenotype as demonstrated by manipulating its expression and/or by in vitro mutagenesis. CA IX can function as a survival factor protecting tumor cells from hypoxia and acidosis, as a pro-migratory factor facilitating cell movement and invasion, as a signaling molecule transducing extracellular signals to intracellular pathways (including major signaling and metabolic cascades) and converting intracellular signals to extracellular effects on adhesion, proteolysis, and other processes. These functional implications of CA IX in cancer are supported by numerous clinical studies demonstrating the association of CA IX with various clinical correlates and markers of aggressive tumor behavior. Although our understanding of the many faces of CA IX is still incomplete, existing knowledge supports the view that CA IX is a biologically and clinically relevant molecule, exploitable in anticancer strategies aimed at targeting adaptive responses to hypoxia and/or acidosis.

  13. Analysis of Rare Earth Elements (REE) in vein quartz and quartz-sandstone host rock in the Zhelannoe high purity quartz deposit, Russia

    NASA Astrophysics Data System (ADS)

    Zemskova, Marina; Prokofiev, Vsevolod; Bychkov, Andrey

    2015-04-01

    The Zhelannoe high purity quartz deposit is located on the western slope of the Polar Urals. It is one of the largest deposits of vein quartz and rock crystal in Russia. Most of the mineralization is hosted within a single horizon of very firm quartz-sandstone, where plastic deformation did not occur almost entirely. All tectonic stress was released by the development of numerous thrust faults of different scales. Cavities formed during this process were later filled with quartz and rock crystal. In order to obtain more details on conditions under which mineralization took place, analysis of trace element contents in vein quartz and host rocks, and the micro-thermometric study of fluid inclusions in quartz have been carried out. The trace element composition of vein quartz and of the host rock has been determined by ICP-MS. The results have shown that concentrations of most of the 46 studied elements in quartz are two orders of magnitude lower than in chondrite, and more than three orders of magnitude lower than in the upper crust. Even though Pb and Li have the highest concentrations in quartz samples, levels are only nearly comparable in chondrite, and substantially lower in the upper crust. At the same time, negative anomalies of Pb and Li concentrations in the host rock may indicate the removal of these elements during vein quartz formation. Contents of most REEs are two orders of magnitude lower than in chondrite, and three orders of magnitude lower than in the host rock. Generally, the patterns of REE distribution in vein quartz and the host rock express a clear correlation; confirming the genetic link between vein quartz and quartz-sandstone host rock. However, the process of quartz recrystallization led to an intense decrease of REEs content, and of all other impurities, which consequently influenced industrial value of the Zhelannoe deposit. As a result of the micro-thermometric study of fluid inclusions in quartz, the following physical

  14. Determination of trace impurities in high-purity zirconium dioxide by inductively coupled plasma atomic emission spectrometry using microwave-assisted digestion and wavelet transform-based correction procedure.

    PubMed

    Ma, Xiaoguo; Li, Yibing

    2006-10-02

    This paper describes a rapid, accurate and precise method for the determination of trace Fe, Hf, Mn, Na, Si and Ti in high-purity zirconium dioxide (ZrO2) powders by inductively coupled plasma atomic emission spectrometry (ICP-AES). The samples were dissolved by a microwave-assisted digestion system. Four different digestion programs with various reagents were tested. It was found that using a mixture of sulfuric acid (H2SO4) and ammonium sulfate ((NH4)2SO4), the total sample dissolution time was 30 min, much shorter than that required for conventional digestion in an opening system. The determination of almost all of the target analytes suffered from spectral interferences, since Zr shows a line-rich atomic emission spectrometry. The wavelet transform (WT), a recently developed mathematical technique was applied to the correction of spectral interference, and more accurate and precise results were obtained, compared with traditional off-peak background correction procedure. Experimental work revealed that a high Zr concentration would result in a significant decrease in peak height of the analyte lines, which was corrected by standard addition method. The performance of the developed method was evaluated by using synthetic samples. The recoveries were in the range of 87-112% and relative standard deviation was within 1.1-3.4%. The detection limits (3sigma) for Fe, Hf, Mn, Na, Si and Ti were found to be 1.2, 13.3, 1.0, 4.5, 5.8 and 2.0 microg g(-1), respectively. The results showed that with the microwave-assisted digestion and the WT correction, the detection limits have improved by a factor of about 5 for Fe, 4 for Mn and Ti, 3 for Si, and 2 for Hf and Na, respectively, in comparison with conventional open-system digestion and off-peak correction. The proposed technique was applied to the analysis of trace elements above-mentioned in three types of ZrO2 powders.

  15. Ares I-X 30 Day Report

    NASA Technical Reports Server (NTRS)

    Ess, Bob; Smith, Marshall

    2009-01-01

    This slide presentation represents the 30 day report on the Ares I-X test flight. Included in the review is information on the following areas: (1) Ground Systems, (2) Guidance, Navigation and Control, (3) Roll Response, (4) Vehicle Response, (5) Control System Performance, (6) Structural Damping, (7) Thrust Oscillation, (8) Stage Separation, (9) Connector Assessment, (10) USS Splashdown, (11) Data Recorder and (12) FS Hardware Assessment.

  16. Glycoprotein Ib-IX-V Complex Transmits Cytoskeletal Forces That Enhance Platelet Adhesion.

    PubMed

    Feghhi, Shirin; Munday, Adam D; Tooley, Wes W; Rajsekar, Shreya; Fura, Adriane M; Kulman, John D; López, Jose A; Sniadecki, Nathan J

    2016-08-09

    Platelets bind to exposed vascular matrix at a wound site through a highly specialized surface receptor, glycoprotein (GP) Ib-IX-V complex, which recognizes von Willebrand factor (VWF) in the matrix. GPIb-IX-V is a catch bond for it becomes more stable as force is applied to it. After attaching to the wound site, platelets generate cytoskeletal forces to compact and reinforce the hemostatic plug. Here, we evaluated the role of the GPIb-IX-V complex in the transmission of cytoskeletal forces. We used arrays of flexible, silicone nanoposts to measure the contractility of individual platelets on VWF. We found that a significant proportion of cytoskeletal forces were transmitted to VWF through GPIb-IX-V, an unexpected finding given the widely held notion that platelet forces are transmitted exclusively through its integrins. In particular, we found that the interaction between GPIbα and the A1 domain of VWF mediates this force transmission. We also demonstrate that the binding interaction between GPIbα and filamin A is involved in force transmission. Furthermore, our studies suggest that cytoskeletal forces acting through GPIbα are involved in maintaining platelet adhesion when external forces are absent. Thus, the GPIb-IX-V/VWF bond is able to transmit force, and uses this force to strengthen the bond through a catch-bond mechanism. This finding expands our understanding of how platelets attach to sites of vascular injury, describing a new, to the best of our knowledge, mechanism in which the catch bonds of GPIb-IX-V/VWF can be supported by internal forces produced by cytoskeletal tension.

  17. DISCLOSING THE INTERACTION OF CARBONIC ANHYDRASE IX WITH CULLIN-ASSOCIATED NEDD8-DISSOCIATED PROTEIN 1 BY MOLECULAR MODELING AND INTEGRATED BINDING MEASUREMENTS.

    PubMed

    Buonanno, Martina; Langella, Emma; Zambrano, Nicola; Succoio, Mariangela; Sasso, Emanuele; Alterio, Vincenzo; Di Fiore, Anna; Sandomenico, Annamaria; Supuran, Claudiu T; Scaloni, Andrea; Monti, Simona Maria; De Simone, Giuseppina

    2017-04-07

    Human Carbonic Anhydrase (hCA) IX is a membrane-associated member of the CA enzyme family, involved in solid tumor acidification. This enzyme is a marker of tumor hypoxia and a prognostic factor for several human cancers. In a recent paper we showed that CA IX interacts with cullin-associated NEDD8-dissociated protein 1 (CAND1), a nuclear protein involved in gene transcription and assembly of SCF ubiquitin ligase complexes. A functional role for this interaction was also identified, since lower CA IX levels were observed in cells with decreased CAND1 expression via shRNA-mediated interference. In this paper, we describe the identification of the structural determinants responsible of the CA IX/CAND1 interaction by means of a multidisciplinary approach, consisting of binding assay measurements, molecular docking and site-directed mutagenesis. These data open a novel scenario in the design of anticancer drugs targeting CA IX. Indeed, the knowledge of the structural determinants responsible for the CAND1/CA IX interaction provides the molecular basis to design molecules able to destabilize it. Due to the proposed function of CAND1 in stabilizing CA IX, these molecules could represent an efficient tool to lower the amount of CA IX in hypoxic cancer cells, thus limiting its action in survival and metastatic spread of tumors.

  18. eEF1A1 binds and enriches protoporphyrin IX in cancer cells in 5-aminolevulinic acid based photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Fan, Zhichao; Cui, Xiaojun; Wei, Dan; Liu, Wei; Li, Buhong; He, Hao; Ye, Huamao; Zhu, Naishuo; Wei, Xunbin

    2016-05-01

    Photodynamic therapy (PDT) with protoporphyrin IX (PpIX), which is endogenously derived from 5-aminolevulinic acid (5-ALA) or its derivatives, is a promising modality for the treatment of both pre-malignant and malignant lesions. However, the mechanisms of how ALA-induced PpIX selectively accumulated in the tumors are not fully elucidated. Here we discovered that eukaryotic translation elongation factor 1 alpha 1 (eEF1A1) interacted with PpIX (with an affinity constant of 2.96 × 106 M‑1). Microscopy imaging showed that ALA-induced PpIX was co-localized with eEF1A1 in cancer cells. eEF1A1 was found to enrich ALA-induced PpIX in cells by competitively blocking the downstream bioavailability of PpIX. Taken together, our study discovered eEF1A1 as a novel photosensitizer binding protein, which may play an essential role in the enrichment of ALA-induced PpIX in cancer cells during PDT. These suggested eEF1A1 as a molecular marker to predict the selectivity and efficiency of 5-ALA based PDT in cancer therapy.

  19. Toxoplasma gondii AP2IX-4 Regulates Gene Expression during Bradyzoite Development.

    PubMed

    Huang, Sherri; Holmes, Michael J; Radke, Joshua B; Hong, Dong-Pyo; Liu, Ting-Kai; White, Michael W; Sullivan, William J

    2017-01-01

    Toxoplasma gondii is a protozoan parasite of great importance to human and animal health. In the host, this obligate intracellular parasite persists as a tissue cyst that is imperceptible to the immune response and unaffected by current therapies. The tissue cysts facilitate transmission through predation and give rise to chronic cycles of toxoplasmosis in immunocompromised patients. Transcriptional changes accompany conversion of the rapidly replicating tachyzoites into the encysted bradyzoites, and yet the mechanisms underlying these alterations in gene expression are not well defined. Here we show that AP2IX-4 is a nuclear protein exclusively expressed in tachyzoites and bradyzoites undergoing division. Knockout of AP2IX-4 had no discernible effect on tachyzoite replication but resulted in a reduced frequency of tissue cyst formation following alkaline stress induction-a defect that is reversible by complementation. AP2IX-4 has a complex role in regulating bradyzoite gene expression, as the levels of many bradyzoite mRNAs dramatically increased beyond those seen under conditions of normal stress induction in AP2IX-4 knockout parasites exposed to alkaline media. The loss of AP2IX-4 also resulted in a modest virulence defect and reduced cyst burden in chronically infected mice, which was reversed by complementation. These findings illustrate that the transcriptional mechanisms responsible for tissue cyst development operate across the intermediate life cycle from the dividing tachyzoite to the dormant bradyzoite. IMPORTANCEToxoplasma gondii is a single-celled parasite that persists in its host as a transmissible tissue cyst. How the parasite converts from its replicative form to the bradyzoites housed in tissue cysts is not well understood, but the process clearly involves changes in gene expression. Here we report that parasites lacking a cell cycle-regulated transcription factor called AP2IX-4 display reduced frequencies of tissue cyst formation in culture and

  20. Toxoplasma gondii AP2IX-4 Regulates Gene Expression during Bradyzoite Development

    PubMed Central

    Huang, Sherri; Holmes, Michael J.; Radke, Joshua B.; Hong, Dong-Pyo; Liu, Ting-Kai; White, Michael W.

    2017-01-01

    ABSTRACT Toxoplasma gondii is a protozoan parasite of great importance to human and animal health. In the host, this obligate intracellular parasite persists as a tissue cyst that is imperceptible to the immune response and unaffected by current therapies. The tissue cysts facilitate transmission through predation and give rise to chronic cycles of toxoplasmosis in immunocompromised patients. Transcriptional changes accompany conversion of the rapidly replicating tachyzoites into the encysted bradyzoites, and yet the mechanisms underlying these alterations in gene expression are not well defined. Here we show that AP2IX-4 is a nuclear protein exclusively expressed in tachyzoites and bradyzoites undergoing division. Knockout of AP2IX-4 had no discernible effect on tachyzoite replication but resulted in a reduced frequency of tissue cyst formation following alkaline stress induction—a defect that is reversible by complementation. AP2IX-4 has a complex role in regulating bradyzoite gene expression, as the levels of many bradyzoite mRNAs dramatically increased beyond those seen under conditions of normal stress induction in AP2IX-4 knockout parasites exposed to alkaline media. The loss of AP2IX-4 also resulted in a modest virulence defect and reduced cyst burden in chronically infected mice, which was reversed by complementation. These findings illustrate that the transcriptional mechanisms responsible for tissue cyst development operate across the intermediate life cycle from the dividing tachyzoite to the dormant bradyzoite. IMPORTANCE Toxoplasma gondii is a single-celled parasite that persists in its host as a transmissible tissue cyst. How the parasite converts from its replicative form to the bradyzoites housed in tissue cysts is not well understood, but the process clearly involves changes in gene expression. Here we report that parasites lacking a cell cycle-regulated transcription factor called AP2IX-4 display reduced frequencies of tissue cyst formation in

  1. Constitutive episomal expression of polypeptide IX (pIX) in a 293-based cell line complements the deficiency of pIX mutant adenovirus type 5.

    PubMed Central

    Caravokyri, C; Leppard, K N

    1995-01-01

    The human adenovirus type 5 capsid is composed of a number of distinct polypeptides. It has been shown previously that one of these, polypeptide IX (pIX), is not absolutely required for the production of viable virus. However, viruses lacking this polypeptide have a significantly reduced packaging limit and, in the one case studied, also show a thermolabile virion phenotype. This report describes the use of eukaryotic episomal vectors based on the Epstein-Barr virus replicon to generate cells which stably express pIX. These cells provide pIX that is efficiently incorporated into virions that are genetically pIX-; such enhanced thermostability. These cells have also been used to isolate a genetically pIX- virus having a genome of length some 2.3 kbp in excess of the previously defined packaging limit for pIX- virus; the resulting virions have wild-type thermostability. These cells expand the theoretical capacity of adenovirus vectors for foreign DNA to around 9.2 kbp and may therefore be useful in gene therapy applications in which vector capacity is limiting. PMID:7474071

  2. Enhancing protoporphyrin IX-induced PDT

    NASA Astrophysics Data System (ADS)

    Curnow, Alison; Pye, Andrew; Campbell, Sandra

    2009-06-01

    Photodynamic therapy (PDT) using porphyrin precursors is commonly used in dermatology. Evidence indicates that good clinical outcomes (associated with excellent cosmesis) can be achieved in superficial precancers and basal cell carcinoma (BCC), however, efficacy appears less favorable for thicker nodular BCC (nBCC) unless multiple PDT treatment cycles are performed. Enhancement is therefore required if nBCC lesions are to be treated effectively with a single PDT treatment. The most common technique currently being routinely employed clinically is the use of aminolevulinic acid (ALA) esters (usually methyl (MAL) or hexyl (HAL)). Standard dermatological PDT employing these porphyrin precursors already manipulates the normal heme biosynthesis pathway resulting in a temporary accumulation of the natural photosensitizer, protoporphyrin IX (PpIX). Further manipulation using iron chelating agents is possible however. In normal and malignant human cells in vitro, the novel iron chelating agent CP94 produced greater PPIX fluorescence when administered with ALA or MAL than either congener produced alone. CP94 was also significantly more effective than the clinically established iron chelating agent desferrioxamine (DFO). Topical application of ALA+CP94 to clinical nBCC lesions was a simple and safe treatment modification which produced a significant increase in clinical clearance when CP94 was included in the cream.

  3. Ares I-X Ascent Base Environments

    NASA Technical Reports Server (NTRS)

    Mobley, B. L.; Bender, R. L.; Canabal, F.; Smith, Sheldon D.

    2011-01-01

    Plume induced base heating environments were measured during the flight of the NASA Constellation Ares I-X developmental launch vehicle, successfully flown on October 28, 2009. The Ares IX first stage is a four segment Space Shuttle derived booster with base consisting of a flared aft skirt, deceleration and tumble motors, and a thermal curtain surrounding the first stage 7.2 area ratio nozzle. Developmental Flight Instrumentation (DFI) consisted of radiometers, calorimeters, pressure transducers and gas temperature probes installed on the aft skirt and nozzle to measure the base environments. In addition, thermocouples were also installed between the layers of the flexible thermal curtain to provide insight into the curtain response to the base environments and to assist in understanding curtain failure during reentry. Plume radiation environment predictions were generated by the Reverse Monte Carlo (RMC) code and the convective base heating predictions utilized heritage MSFC empirical methods. These predictions were compared to the DFI data and results from the flight videography. Radiation predictions agreed with the flight measured data early in flight but gauge failures prevented high altitude comparisons. The convective environment comparisons demonstrated the need to improve the prediction methodology; particularly for low altitude, local plume recirculation. The convective comparisons showed relatively good agreement at altitudes greater than 50,000 feet.

  4. Electron Impact Exciation of Fe IX

    NASA Astrophysics Data System (ADS)

    Tayal, Swaraj; Zatsarinny, Oleg

    2015-05-01

    Transition probabilities and electron impact excitation collision strengths and rates for astrophysically important extreme ultraviolet lines of Fe IX are calculated. The 322 fine-structure levels of the 3s2 3p6 , 3s2 3p5 3 d , 3 s 3p6 3 d , 3s2 3p5 4 s , and 3s2 3p4 3d2 configurations are included in our calculations. The collision strengths have been calculated using the B-spline Breit-Pauli R-matrix method for all fine-structure transitions among the 322 levels. The mass, Darwin, and spin-orbit relativistic effects are included in the Breit-Pauli Hamiltonian in the scattering calculation. The one-body and two-body relativistic operators are included in the multi-configuration Hartree-Fock calculations of transition probabilities. Several sets of non-orthogonal spectroscopic and correlation radial orbitals are used to obtain accurate description of Fe IX levels and to represent the scattering functions. The calculated excitation energies are in very good agreement with experiment and represents an improvement over the previous calculations. The present collision strengths show reasonable agreement with the previously available R-matrix and distorted-wave calculations. This research is supported by NASA grant from the Solar and Heliophysics Program.

  5. Ares I-X Ground Diagnostic Prototype

    NASA Technical Reports Server (NTRS)

    Schwabacher, Mark A.; Martin, Rodney Alexander; Waterman, Robert D.; Oostdyk, Rebecca Lynn; Ossenfort, John P.; Matthews, Bryan

    2010-01-01

    The automation of pre-launch diagnostics for launch vehicles offers three potential benefits: improving safety, reducing cost, and reducing launch delays. The Ares I-X Ground Diagnostic Prototype demonstrated anomaly detection, fault detection, fault isolation, and diagnostics for the Ares I-X first-stage Thrust Vector Control and for the associated ground hydraulics while the vehicle was in the Vehicle Assembly Building at Kennedy Space Center (KSC) and while it was on the launch pad. The prototype combines three existing tools. The first tool, TEAMS (Testability Engineering and Maintenance System), is a model-based tool from Qualtech Systems Inc. for fault isolation and diagnostics. The second tool, SHINE (Spacecraft Health Inference Engine), is a rule-based expert system that was developed at the NASA Jet Propulsion Laboratory. We developed SHINE rules for fault detection and mode identification, and used the outputs of SHINE as inputs to TEAMS. The third tool, IMS (Inductive Monitoring System), is an anomaly detection tool that was developed at NASA Ames Research Center. The three tools were integrated and deployed to KSC, where they were interfaced with live data. This paper describes how the prototype performed during the period of time before the launch, including accuracy and computer resource usage. The paper concludes with some of the lessons that we learned from the experience of developing and deploying the prototype.

  6. Dexamethasone downregulates expression of carbonic anhydrase IX via HIF-1α and NF-κB-dependent mechanisms

    PubMed Central

    Simko, Veronika; Takacova, Martina; Debreova, Michaela; Laposova, Katarina; Ondriskova-Panisova, Elena; Pastorekova, Silvia; Csaderova, Lucia; Pastorek, Jaromir

    2016-01-01

    Dexamethasone is a synthetic glucocorticoid frequently used to suppress side-effects of anticancer chemotherapy. In the present study, we showed that dexamethasone treatment leads to concentration-dependent downregulation of cancer-associated marker, carbonic anhydrase IX (CA IX), at the level of promoter activity, mRNA and protein expression in 2D and 3D cancer cell models. The effect of dexamethasone on CA IX expression under hypoxic conditions is predominantly mediated by impaired transcriptional activity and decreased protein level of the main hypoxic transcription factor HIF-1α. In addition, CA9 downregulation can be caused by protein-protein interactions between activated glucocorticoid receptors, major effectors of glucocorticoid action, and transcription factors that trigger CA9 transcription (e.g. AP-1). Moreover, we identified a potential NF-κB binding site in the CA9 promoter and propose the involvement of NF-κB in the dexamethasone-mediated inhibition of CA9 transcription. As high level of CA IX is often linked to aggressive tumor behavior, poor prognosis and chemo- and radiotherapy resistance, uncovering its reduction after dexa-methasone treatment and implication of additional regulatory mechanisms can be relevant for the CA IX-related clinical applications. PMID:27431580

  7. Tilting the Playing Field: Schools, Sports, Sex and Title IX.

    ERIC Educational Resources Information Center

    Gavora, Jessica

    This book suggests that Title IX of the Education Amendments is not creating more female athletes but instead eliminating some of the most prestigious men's sports programs in the name of gender equity. It shows how Title IX has affected every aspect of education, from kindergarten through graduate school, making profound changes in areas as…

  8. Beyond Title IX: Gender Equity Issues in Schools.

    ERIC Educational Resources Information Center

    NETWORK, Inc., Andover, MA.

    This document is one of a two-part set of publications. Both deal with equal education and provide a concise overview of Title IX and gender equity issues in education and steps to take to ensure nondiscrimination and equal education opportunity for all. Title IX of the Education Amendments of 1972 mandates that schools not deny any student…

  9. School Environment and Academic Achievement of Standard IX Students

    ERIC Educational Resources Information Center

    Lawrence, A. S. Arul; Vimala, A.

    2012-01-01

    The present study School Environment and Academic Achievement of standard IX students was probed to find the relationship between School Environment and Academic Achievement of standard IX students. Data for the study were collected using self-made School Environment Scale (SES). The investigator used stratified random sampling technique for…

  10. A License for Bias: Sex Discrimination, Schools, and Title IX.

    ERIC Educational Resources Information Center

    Morse, Susan Ed.

    This report discusses non-sports-related Title IX complaints filed with the Department of Education's Office for Civil Rights (OCR) from 1993-1997. Its purpose is to dispel the popular belief that Title IX is a sports-equity law and to determine the effectiveness of the legislation. The document examines the kinds of complaints filed, the status…

  11. The History, Uses, and Abuses of Title IX. 2016 Bulletin

    ERIC Educational Resources Information Center

    American Association of University Professors, 2016

    2016-01-01

    This report, an evaluation of the history and current uses of Title IX, is the result of a joint effort by a subcommittee that included members of the AAUP's Committee A on Academic Freedom and Tenure and the Committee on Women in the Academic Profession. The report identifies tensions between current interpretations of Title IX and the academic…

  12. A Model Community College Grievance Procedure for Title IX.

    ERIC Educational Resources Information Center

    Noonan, Roberta L.

    Through a review of the literature, analysis of eleven Title IX grievance plans, and interviews with four compliance officers, twelve criteria essential to an effective grievance procedure for use by students were identified and incorporated into a model Title IX grievance procedure for Moraine Valley Community College (Illinois). The twelve…

  13. ARES I-X USS Fracture Analysis Loads Spectra Development

    NASA Technical Reports Server (NTRS)

    Larsen, Curtis; Mackey, Alden

    2008-01-01

    This report describes the development of a set of bounding load spectra for the ARES I-X launch vehicle. These load spectra are used in the determination of the critical initial flaw size (CIFS) of the welds in the ARES I-X upper stage simulator (USS).

  14. Ares I-X Ground Diagnostic Prototype

    NASA Technical Reports Server (NTRS)

    Schwabacher, Mark; Martin, Rodney; Waterman, Robert; Oostdyk, Rebecca; Ossenfort, John; Matthews, Bryan

    2010-01-01

    Automating prelaunch diagnostics for launch vehicles offers three potential benefits. First, it potentially improves safety by detecting faults that might otherwise have been missed so that they can be corrected before launch. Second, it potentially reduces launch delays by more quickly diagnosing the cause of anomalies that occur during prelaunch processing. Reducing launch delays will be critical to the success of NASA's planned future missions that require in-orbit rendezvous. Third, it potentially reduces costs by reducing both launch delays and the number of people needed to monitor the prelaunch process. NASA is currently developing the Ares I launch vehicle to bring the Orion capsule and its crew of four astronauts to low-earth orbit on their way to the moon. Ares I-X will be the first unmanned test flight of Ares I. It is scheduled to launch on October 27, 2009. The Ares I-X Ground Diagnostic Prototype is a prototype ground diagnostic system that will provide anomaly detection, fault detection, fault isolation, and diagnostics for the Ares I-X first-stage thrust vector control (TVC) and for the associated ground hydraulics while it is in the Vehicle Assembly Building (VAB) at John F. Kennedy Space Center (KSC) and on the launch pad. It will serve as a prototype for a future operational ground diagnostic system for Ares I. The prototype combines three existing diagnostic tools. The first tool, TEAMS (Testability Engineering and Maintenance System), is a model-based tool that is commercially produced by Qualtech Systems, Inc. It uses a qualitative model of failure propagation to perform fault isolation and diagnostics. We adapted an existing TEAMS model of the TVC to use for diagnostics and developed a TEAMS model of the ground hydraulics. The second tool, Spacecraft Health Inference Engine (SHINE), is a rule-based expert system developed at the NASA Jet Propulsion Laboratory. We developed SHINE rules for fault detection and mode identification. The prototype

  15. Crystal structure of the catalytic domain of the tumor-associated human carbonic anhydrase IX.

    PubMed

    Alterio, Vincenzo; Hilvo, Mika; Di Fiore, Anna; Supuran, Claudiu T; Pan, Peiwen; Parkkila, Seppo; Scaloni, Andrea; Pastorek, Jaromir; Pastorekova, Silvia; Pedone, Carlo; Scozzafava, Andrea; Monti, Simona Maria; De Simone, Giuseppina

    2009-09-22

    Carbonic anhydrase (CA) IX is a plasma membrane-associated member of the alpha-CA enzyme family, which is involved in solid tumor acidification. It is a marker of tumor hypoxia and a prognostic factor in several human cancers. An aberrant increase in CA IX expression in chronic hypoxia and during development of various carcinomas contributes to tumorigenesis through at least two mechanisms: pH regulation and cell adhesion control. Here we report the X-ray structure of the catalytic domain of CA IX in complex with a classical, clinically used sulfonamide inhibitor, acetazolamide. The structure reveals a typical alpha-CA fold, which significantly differs from the other CA isozymes when the protein quaternary structure is considered. Thus, two catalytic domains of CA IX associate to form a dimer, which is stabilized by the formation of an intermolecular disulfide bond. The active site clefts and the PG domains are located on one face of the dimer, while the C-termini are located on the opposite face to facilitate protein anchoring to the cell membrane. A correlation between the three-dimensional structure and the physiological role of the enzyme is here suggested, based on the measurement of the pH profile of the catalytic activity for the physiological reaction, CO(2) hydration to bicarbonate and protons. On the basis of the structural differences observed between CA IX and the other membrane-associated alpha-CAs, further prospects for the rational drug design of isozyme-specific CA inhibitors are proposed, given that inhibition of this enzyme shows antitumor activity both in vitro and in vivo.

  16. Nitric oxide inhibits the formation of zinc protoporphyrin IX and protoporphyrin IX.

    PubMed

    Wakamatsu, Jun-ichi; Hayashi, Nobutaka; Nishimura, Takanori; Hattori, Akihito

    2010-01-01

    The aim of this study was to elucidate the mechanism by which curing agents, especially nitrite, inhibit the formation of zinc protoporphyrin IX (ZPP) in dry-cured hams such as Parma ham. The oxidation-reduction potential of model solutions was increased by the addition of nitrite, but it was not clear whether the formation of ZPP is inhibited by the oxidizing property of nitrite. The effect of nitric oxide (NO) produced from nitrite on the formation of ZPP was examined. The amount of ZPP formed was decreased by the addition of NO donors. The amount of protoporphyrin IX (PPIX), which is the precursor of ZPP, was also decreased by the addition of NO donors. It is concluded that NO produced from nitrite inhibited the formation of PPIX and ZPP was therefore not formed in cured meat products with the addition of nitrite or nitrate.

  17. Quantitative determination of Zn protoporphyrin IX, heme and protoporphyrin IX in Parma ham by HPLC.

    PubMed

    Wakamatsu, Jun-Ichi; Odagiri, Hiroko; Nishimura, Takanori; Hattori, Akihito

    2009-05-01

    We measured the contents of Zn protoporphyrin IX (ZPP), heme and protoporphyrin IX (PPIX) in Parma ham by simultaneous analysis using high-performance liquid chromatography (HPLC). Extraction with ethyl acetate-acetic acid (4:1) was suitable for the quantitative analysis of ZPP. The contents of heme, ZPP and PPIX in Parma ham were 15.0-29.9, 27.7-47.0 and 0.4-1.1μg/g, respectively, and total content of porphyrin was 43.7-76.6μg/g. The amount of ZPP in Parma ham was larger than that of heme, and ZPP accounted for 60-70% of all porphyrins.

  18. Ares I-X USS Material Testing

    NASA Technical Reports Server (NTRS)

    Dawicke, David S.; Smith, Stephen W.; Raju, Ivatury S.

    2008-01-01

    An independent assessment was conducted to determine the critical initial flaw size (CIFS) for the flange-to-skin weld in the Ares I-X Upper Stage Simulator (USS). Material characterization tests were conducted to quantify the material behavior for use in the CIFS analyses. Fatigue crack growth rate, Charpy impact, and fracture tests were conducted on the parent and welded A516 Grade 70 steel. The crack growth rate tests confirmed that the material behaved in agreement with literature data and that a salt water environment would not significantly degrade the fatigue resistance. The Charpy impact tests confirmed that the fracture resistance of the material did not have a significant reduction for the expected operational temperatures of the vehicle.

  19. Ares I-X Flight Test Philosophy

    NASA Technical Reports Server (NTRS)

    Davis, S. R.; Tuma, M. L.; Heitzman, K.

    2007-01-01

    In response to the Vision for Space Exploration, the National Aeronautics and Space Administration (NASA) has defined a new space exploration architecture to return humans to the Moon and prepare for human exploration of Mars. One of the first new developments will be the Ares I Crew Launch Vehicle (CLV), which will carry the Orion Crew Exploration Vehicle (CEV), into Low Earth Orbit (LEO) to support International Space Station (ISS) missions and, later, support lunar missions. As part of Ares I development, NASA will perform a series of Ares I flight tests. The tests will provide data that will inform the engineering and design process and verify the flight hardware and software. The data gained from the flight tests will be used to certify the new Ares/Orion vehicle for human space flight. The primary objectives of this first flight test (Ares I-X) are the following: Demonstrate control of a dynamically similar integrated Ares CLV/Orion CEV using Ares CLV ascent control algorithms; Perform an in-flight separation/staging event between an Ares I-similar First Stage and a representative Upper Stage; Demonstrate assembly and recovery of a new Ares CLV-like First Stage element at Kennedy Space Center (KSC); Demonstrate First Stage separation sequencing, and quantify First Stage atmospheric entry dynamics and parachute performance; and Characterize the magnitude of the integrated vehicle roll torque throughout the First Stage (powered) flight. This paper will provide an overview of the Ares I-X flight test process and details of the individual flight tests.

  20. Comparison of expression systems for human fucosyltransferase IX.

    PubMed

    Stacke, Christina; Ziegelmüller, Patrick; Hahn, Ulrich

    2010-01-01

    Human fucosyltransferase IX (hFucT-IX) is a highly conserved alpha1,3 fucosyltransferase with a distinct acceptor and site specificity. hFucT-IX catalyses the transfer of activated fucose to a sugar acceptor, thereby forming the Lewis x epitope. This epitope is responsible for recognition phenomena throughout the body e.g. in tumour growth. Detailed characterisation of hFucT-IX structure-function relationships by kinetic and X-ray structure analysis is prerequisite to the development of enzyme inhibitors for clinical applications such as the suppression of tumour metastasis. For these analyses substantial amounts of hFucT-IX are desirable. Since hFucT-IX is not present in considerable amounts in common cells an overproduction of recombinant hFucT-IX is appropriate. To evaluate the best system for this overproduction we compared different strategies employing prokaryotes (Escherichia coli), mammalian cells and insect cells. Insect cells were tested using stable and baculoviral expression strategies. Current results favour the use of the baculoviral expression system for further experiments.

  1. ALA-induced PpIX fluorescence in epileptogenic tissue

    NASA Astrophysics Data System (ADS)

    Kleen, Jonathan K.; Valdes, Pablo A.; Harris, Brent T.; Holmes, Gregory L.; Paulsen, Keith D.; Roberts, David W.

    2011-03-01

    Astrogliotic tissue displays markedly increased levels of ALA-induced PpIX fluorescence, making it useful for fluorescence-guided resection in glioma surgery. In patients with temporal lobe epilepsy (TLE) and corresponding animal models, there are areas of astrogliosis that often co-localize with the epileptic focus, which can be resected to eliminate seizures in the majority of treated patients. If this epileptogenic tissue can exhibit PpIX fluorescence that is sufficiently localized, it could potentially help identify margins in epilepsy surgery. We tested the hypothesis that ALA-induced PpIX fluorescence could visually accentuate epileptogenic tissue, using an established animal model of chronic TLE. An acute dose of pilocarpine was used to induce chronic seizure activity in a rat. This rat and a normal control were given ALA, euthanized, and brains examined post-mortem for PpIX fluorescence and neuropathology. Preliminary evidence indicates increased PpIX fluorescence in areas associated with chronic epileptic changes and seizure generation in TLE, including the hippocampus and parahippocampal areas. In addition, strong PpIX fluorescence was clearly observed in layer II of the piriform cortex, a region known for epileptic reorganization and involvement in the generation of seizures in animal studies. We are further investigating whether ALA-induced PpIX fluorescence can consistently identify epileptogenic zones, which could warrant the extension of this technique to clinical studies for use as an adjuvant guidance technology in the resection of epileptic tissue.

  2. IBM PC/IX operating system evaluation plan

    NASA Technical Reports Server (NTRS)

    Dominick, Wayne D. (Editor); Granier, Martin; Hall, Philip P.; Triantafyllopoulos, Spiros

    1984-01-01

    An evaluation plan for the IBM PC/IX Operating System designed for IBM PC/XT computers is discussed. The evaluation plan covers the areas of performance measurement and evaluation, software facilities available, man-machine interface considerations, networking, and the suitability of PC/IX as a development environment within the University of Southwestern Louisiana NASA PC Research and Development project. In order to compare and evaluate the PC/IX system, comparisons with other available UNIX-based systems are also included.

  3. Measurements of gamma (γ)-emitting radionuclides with a high-purity germanium detector: the methods and reliability of our environmental assessments on the Fukushima 1 Nuclear Power Plant accident.

    PubMed

    Mimura, Tetsuro; Mimura, Mari; Komiyama, Chiyo; Miyamoto, Masaaki; Kitamura, Akira

    2014-01-01

    The severe accident of Fukushima 1 Nuclear Power Plant due to the Tohoku Region Pacific Coast Earthquake in 11 March 2011 caused wide contamination and pollution by radionuclides in Fukushima and surrounding prefectures. In the current JPR symposium, a group of plant scientists attempted to examine the impact of the radioactive contamination on wild and cultivated plants. Measurements of gamma (γ) radiation from radionuclides in "Fukushima samples", which we called and collected from natural and agricultural areas in Fukushima prefecture were mostly done with a high-purity Ge detector in the Graduate School of Maritime Sciences, Kobe University. In this technical note, we describe the methods of sample preparation and measurements of radioactivity of the samples and discuss the reliability of our data in regards to the International Atomic Energy Agency (IAEA) Interlaboratory comparisons and proficiency test (IAEA proficiency test).

  4. Separation of analyte and matrix for the direct analysis of high-purity molybdenum-based materials by electrothermal atomic spectrometry methods—I. Radiotracer investigation of thermal extraction of impurities in a graphite cup

    NASA Astrophysics Data System (ADS)

    Dočekal, Bohumil; Krivan, Viliam; Franek, Martin

    1994-06-01

    By means of radiotracers, thermal vaporization of a number of detrimental trace elements (alkali, alkali earth and heavy metals) from metallic molybdenum powder has been studied. For this purpose, molybdenum samples labelled with appropriate radiotracers of the trace elements were prepared from a slurry of molybdenum oxide, ammonium molybdate solution and a radiotracer solution. Vaporization yields were measured after electrothermal treatment of the samples at temperatures between 1900 and 3000°C. Alkali and alkali earth elements, copper and zinc were vaporized with yields higher than 98%. Possible application of the electrothermal vaporization technique to the direct analysis of high-purity molybdenumbased materials by atomic absorption and atomic emission spectrometry is discussed.

  5. 1,1-dimethylhydrazine as a high purity nitrogen source for MOVPE-water reduction and quantification using nuclear magnetic resonance, gas chromatography-atomic emission detection spectroscopy and cryogenic-mass spectroscopy analytical techniques

    SciTech Connect

    Odedra, R.; Smith, L.M.; Rushworth, S.A.

    2000-01-01

    Hydrazine derivatives are attractive low temperature nitrogen sources for use in MOVPE due to their low thermal stability. However their purification and subsequent analysis has not previously been investigated in depth for this application. A detailed study on 1,1-dimethylhydrazine {l{underscore}brace}(CH{sub 3}){sub 2}N-NH{sub 2}{r{underscore}brace} purified by eight different methods and the subsequent quantitative measurements of water present in the samples obtained is reported here. A correlation between {sup 1}H nuclear magnetic resonance spectroscopy (NMR), gas chromatography-atomic emission detection (GC-AED) and cryogenic mass spectroscopy (Cryogenic-MS) has been performed. All three analysis techniques can be used to measure water in the samples and with the best purification the water content can be lowered well below 100 ppm. The high purity of this material has been demonstrated by growth results and the state-of-the-art performance of laser diodes.

  6. Title IX and Intercollegiate Athletics in the Federal Appellate Courts: Myth vs. Reality.

    ERIC Educational Resources Information Center

    Pieronek, Catherine

    2000-01-01

    Focuses on the enforcement of the nondiscrimination provisions of Title IX in higher education, and shows how the courts have wrestled with the application of Title IX to college athletic programs over the past decade. Provides a history of Title IX enforcement and describes current approaches to evaluating Title IX compliance. (SLD)

  7. Enhanced effects of local moment-carrier couplings in the high-purity alloys CuxM1-x(phthalocyanine)I (M=H2 or Ni)

    NASA Astrophysics Data System (ADS)

    Thompson, Julia A.; Murata, Kazuhiko; Durcharne, Rejean; Poirier, Mario; Hoffman, Brian M.

    1999-07-01

    Utilizing techniques for synthesizing very pure M(pc), (pc=phthalocyanine), we prepared alloys of the type CuxM1-x(pc)I, M=H2 or Ni to examine the interaction between the conduction electrons and the local moments associated with the S=12 CuII metal ions embedded in the macrocycle center. The effects of the local moments, which include large decreases in conductivity and large positive magnetoconductivities, are greatly enhanced in these purer materials. Introduction of 5% Cu(pc) reduces the conductivity by a factor of 3. This same alloy shows a positive magnetoconductivity with a relative increase in conductivity of tenfold; this effect is four times greater than that observed in Cu0.05Ni0.95(pc)I made from commercially available material. Magnetic studies including susceptibility and electron paramagnetic resonance confirm that the two spin systems are strongly coupled. A magnetic susceptibility fit to a Curie-Weiss expression yields a Weiss constant, \\|θ\\|, that increases linearly with x, the Cu content. The slope of \\|θ\\| is explained in the companion paper by Martin and Phillips [Phys. Rev. B 60, 530 (1999)].

  8. 29. Photocopy of 1921 photograph. Glass Negative Box IX, Tower ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    29. Photocopy of 1921 photograph. Glass Negative Box IX, Tower Grove, Missouri Botanical Garden. ITALIAN GARDEN AND NEW PALM HOUSE (DEMOLISHED), LOOKING NORTHEAST - Missouri Botanical Garden, 2345 Tower Grove Avenue, Saint Louis, Independent City, MO

  9. 26. Photocopy of August 1918 photograph. Glass Negative Box IX, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. Photocopy of August 1918 photograph. Glass Negative Box IX, Tower Grove, Missouri Botanical Garden. ITALIAN GARDEN, LOOKING SOUTHWEST - Missouri Botanical Garden, 2345 Tower Grove Avenue, Saint Louis, Independent City, MO

  10. Photosensitizing effect of protoporphyrin IX in pigmented melanoma of mice.

    PubMed

    Juzenas, Petras; Juzeniene, Asta; Stakland, Silje; Iani, Vladimir; Moan, Johan

    2002-09-27

    No fluorescence of protoporphyrin IX (PpIX) was measured using a fiber optic probe in pigmented B16F10 melanoma in mice after topical application of 5-aminolevulinic acid methylester (ALA-Me). However, chemical extraction of tissues excised from mice after intratumoral administration of ALA-Me or its parent compound ALA revealed that this tumor had the capability to produce PpIX. Small amounts of endogenous porphyrins, mainly PpIX, were found in the melanoma not treated with these drugs. Topical application of ALA-Me followed by exposure with laser light (633nm) delayed the growth of the tumors slightly. Light alone also had a significant effect on the tumor growth.

  11. Anisotropic Bianchi types VIII and IX locally rotationally symmetric cosmologies

    SciTech Connect

    Assad, M.J.D.; Soares, I.D.

    1983-10-15

    We present a class of exact cosmological solutions of Einstein-Maxwell equations, which are anisotropic and spatially homogeneous of Bianchi types VIII and IX, and class IIIb in the Stewart-Ellis classification of locally rotationally symmetric models. If we take the electromagnetic field equal to zero, a class of Bianchi types VIII/IX spatially homogeneous anisotropic cosmological solutions with perfect fluid is obtained.

  12. The effects of CA IX catalysis products within tumor microenvironment.

    PubMed

    Santi, Alice; Caselli, Anna; Paoli, Paolo; Corti, Denise; Camici, Guido; Pieraccini, Giuseppe; Taddei, Maria Letizia; Serni, Sergio; Chiarugi, Paola; Cirri, Paolo

    2013-10-29

    Solid tumors are composed of both cancer cells and various types of accessory cells, mainly fibroblasts, that collectively compose the so called tumor-microenvironment. Cancer-associated fibroblasts have been described to actively participate in cancer progression by establishing a cytokine-mediated as well as metabolic crosstalk with cancer cells. In the present paper we show that activated human fibroblasts are able to boost tumor cells proliferation and that this effect is greatly dependent on stromal carbonic anhydrase IX (CA IX) activity. In fact fibroblasts show a strong upregulation of CA IX expression upon activation by cancer cells, while CA IX products, protons and bicarbonate, exert differential effects on cancer cells proliferation. While acidification of extracellular pH, a typical condition of rapidly growing solid tumors, is detrimental for tumor cells proliferation, bicarbonate, through its organication, supplies cancer cells with intermediates useful to sustain their high proliferation rate. Here we propose a new kind of fibroblasts/tumor cells crosstalk within tumor microenvironment, mediated by stromal CA IX products, aimed to favor cancer cells growth, opening new perspectives on CA IX role in tumor microenvironment.

  13. Cloning and functional analysis of spliced isoforms of human nuclear factor I-X: interference with transcriptional activation by NFI/CTF in a cell-type specific manner.

    PubMed Central

    Apt, D; Liu, Y; Bernard, H U

    1994-01-01

    Previous studies of the epithelial specificity of the human papillomavirus type 16 (HPV-16) enhancer pointed out an important role of nuclear factor I (NFI). In epithelial cells, NFI proteins are derived from the NFI-C gene and referred to as NFI/CTF. In contrast, fibroblasts, where the enhancer is inactive, express high levels of NFI from the NFI-X gene. To compare NFI-C and NFI-X derived transcription factors, we cloned and functionally investigated two differentially spliced forms of NFI-X from human fibroblasts. NFI-X1 has 95% homology with a transcript previously identified in hamster liver cells. NFI-X2, a spliced variant, misses 41 amino acids of the proline-rich activation domain. NFI-X expression, examined by Northern blots, shows strong cell-type specific variation in comparison with NFI/CTF. While the transcriptional activation domain of NFI-X2, functionally tested as GAL4-fusion protein in epithelial and fibroblast cells, activates transcription from promoter as well as enhancer position similar to NFI/CTF-1, the activation domain of NFI-X1 fails to activate transcription from enhancer position. In Drosophila cells, void of endogenous NFI proteins, full length NFI/CTF-1 and NFI-X2 activate a reporter construct containing only NFI sites as well as the NFI dependent HPV-16 enhancer. In contrast, NFI-X1 fails to activate the HPV-16 enhancer. Furthermore, overexpression of NFI-X1 in epithelial cells down-regulates the HPV-16 enhancer. Our findings suggest that the family of NFI transcription factors should not be viewed as constitutive activators, but rather, that NFI-C and NFI-X have divergent functions after binding in promoter or enhancer position. This property, combined with the differential expression of NFI-X, can achieve cell-type specificity of NFI dependent promoters and enhancers. Images PMID:7937100

  14. Oxygen Availability for Porphyrin Biosynthesis Enzymes Determines the Production of Protoporphyrin IX (PpIX) during Hypoxia

    PubMed Central

    Otsuka, Shimpei; Matsumoto, Kentaro; Nakajima, Motowo; Tanaka, Tohru; Ogura, Shun-ichiro

    2015-01-01

    5-Aminolevulinic acid (ALA), a precursor of porphyrin, is specifically converted to the fluorescent substance protoporphyrin IX (PpIX) in tumors to be used as a prodrug for photodynamic therapy and diagnosis. Hypoxia, a common feature of solid tumors, decreases the efficacy of ALA-based photodynamic therapy and diagnosis. This decrease results from the excretion of porphyrin precursor coproporphyrinogen III (CPgenIII), an intermediate in the biosynthesis of PpIX. However, the mechanism of CPgenIII excretion during hypoxia remains unclear. In this study, we revealed the importance of mitochondrial respiration for the production of PpIX during hypoxia. Porphyrin concentrations were estimated in human gastric cancer cell lines by HPLC. Expression levels of porphyrin biosynthesis genes were measured by qRT-PCR and immunoblotting. Blockage of porphyrin biosynthesis was an oxygen-dependent phenomenon resulting from decreased PpIX production in mitochondria under hypoxic conditions. PpIX production was increased by the inhibition of mitochondrial respiration complexes, which indicates that the enzymes of porphyrin biosynthesis compete with respiration complexes for molecular oxygen. Our results indicate that targeting the respiration complexes is a rationale for enhancing the effect of ALA-mediated treatment and diagnosis. PMID:26717566

  15. The maintenance of tolerance after successful immune tolerance induction in hemophilia A and B: the North American Registry. Factor VIII/IX Subcommittee of the International Society for Thrombosis and Hemostasis.

    PubMed

    DiMichele, D; Kroner, B

    2000-10-01

    The North American Immune Tolerance Registry (NAITR) was initiated with the goal of determining, by questionnaire, immune tolerance (ITT) practices in hemophilia treatment centers in Canada and the United States. Sixty-eight centers (40%) responded. Of the 130 registry subjects with hemophilia A who completed ITT, 93 (72%) achieved tolerance. Of the 11 completed ITT courses in patients with hemophilia B, 4 (36%) were successful. Maintenance therapy was defined as any dotting factor regimen administered subsequent to the patient achieving the treating physician's criteria for successful immune tolerance. Seventy-five (81%) of 93 individuals in the hemophilia A cohort who successfully achieved tolerance were maintained on a regular (prophylactic factor VIII (FVIII) regimen for a variable time period post-ITT. The median dose used was 150 units/kg/week (range: 17-700). Forty-eight (64%) subjects remained tolerant while receiving regular doses of FVIII for a median observation period of 13 months (range 0-129 months). Of 27 patients whose maintenance therapy had been stopped, 17 (68%) remained tolerant over a median period of 19 months (range 1-54 months) and 9 relapsed. Among the relapses, 3 occurred after maintenance therapy was stopped; 6 were noted on prophylactic FVIII at a median time of 11 months (range 2-61 months). The definition of tolerance was reviewed for the 9 subjects who relapsed and was defined by a normal recovery and survival in only 1/9 patients. Among the 11 hemophilia B subjects in the cohort who completed tolerance, 4 had a successful outcome. Four individuals were placed on maintenance regimens of 25-100 units FIX/kg/day and all remained tolerant.

  16. Liquid biopsy of atherosclerosis using protoporphyrin IX as a biomarker.

    PubMed

    Nascimento da Silva, Monica; Sicchieri, Letícia Bonfante; de Oliveira Silva, Flávia Rodrigues; Andrade, Maira Franco; Courrol, Lilia Coronato

    2014-03-21

    Protoporphyrin IX (PPIX), a derivative of hematoporphyrin, can accumulate in rapidly growing tissues, including tumors and atherosclerotic plaques. The objective of this study is to employ PPIX fluorescence to detect the changes in blood caused by the formation of atheromatous plaques in arteries; this measurement can function as a liquid biopsy. For this purpose twenty four rabbits were randomly divided into groups: control group (CG)--fed with a normal diet, and an experimental group (EG)--fed with a hypercholesterolemic diet (1% cholesterol). Blood samples were collected before (0 time) and after 22, 43, 64 days to measure biochemical factors. The aortas were removed after 22, 43 and 64 days to assess the atherosclerotic plaques. PPIX was extracted from the blood and fluorescence was measured in the 550-750 nm range from samples that were excited at 405 nm. Aminolevulinic acid (ALA) was administered intravenously to increase the PPIX fluorescence intensity in the arteries and consequently in the liquid biopsy of the atherosclerotic plaques. The results have shown that the PPIX fluorescence increased as the atheromatous plaques grew. The aorta fluorescence and the PPIX fluorescence increased in the animals in the experimental group that received ALA. PPIX that accumulates in atheromatous plaques transfers to the blood and can be analyzed by extracting porphyrin from total blood. Therefore, this method can aid in the early diagnosis of atherosclerosis with high sensitivity.

  17. Manufacture of high purity metal fluorides

    SciTech Connect

    Vance, J.M.

    1984-01-01

    The Oak Ridge Gaseous Diffusion Plant has been developing technologies of many kinds since the early forties. The primary purpose of this R and D was to reduce the amount of electrical power and capital expense associated with the enrichment of uranium in the 235 isotope. One area that has received a lot of attention is the chemistry of fluorine and metal fluorides. The producing facility at ORGDP is a chemical pilot plant which has been used through the years to demonstrate new processes. Presently existing in this facility are: absorption columns which have been used to remove trace quantities of krypton and oxides of nitrogen and sulfur from gas streams; a flame reactor that is being used to reduce isotopically altered sulfur hexafluoride for conversion to SO/sub 2/ which will be used in acid rain studies; an environmental hold system in which methods were developed to remove or neutralize environmental insulting compounds; a fluid bed reactor, and of course the tungsten hexafluoride process. A rhenium hexafluoride facility is also located in the pilot plant. It is basically the same as the tungsten line with three small muffles being used in place of the large WF6 reactor. The product from each process is heated and transferred to approved 5-inch shipping cylinders and transported to the analytical chemistry laboratory for sampling and analysis. These cylinders must be used for shipment and may require modification of the customer facility to accommodate them. Liquid samples are obtained from the product cylinders and a visual examination of the samples for color and melting temperature provides a good indication of the conversion. X-ray fluorescence is utilized to determine the amount of tungsten and the percent conversion to the hexafluoride is calculated from the weighed sample. Infrared in addition to mass spectrometer analyses are performed to verify the findings. The material is then analyzed by spectrographic methods for contaminants.

  18. Microwave joining of high-purity alumina

    SciTech Connect

    Cozzi, A.D.; Clark, D.E.; Ferber, M.K.

    1996-12-31

    Microwave hybrid heating (MHH) was used to join 99.5% pure alumina pieces 25 mm diameter and 25 mm long using 94% pure alumina as the interlayer material. The interlayer material was cut from a rod into discs approximately 2 mm thick. Joining was performed in a home model microwave oven. Temperatures for joining ranged from 1450{degrees}C to 1550{degrees}C and pressures from 1-3 MPa. For comparison, similar joints were made in a conventional furnace. Joined specimens were tested using four-point bend at room temperature. Statistical analysis was utilized to determine the relative effect of the different processing parameters on the strength of the joint.

  19. High purity silica reflective heat shield development

    NASA Technical Reports Server (NTRS)

    Blome, J. C.; Drennan, D. N.; Schmitt, R. J.

    1974-01-01

    Measurements were made of reflectance in the vacuum ultraviolet down to 0.15 micron. Scattering coefficients (S) and absorption coefficients (K) were also measured. These coefficients express the optical properties and are used directly in a thermodynamic analysis for sizing a heat shield. The effect of the thin silica melt layer formed during entry was also studied from the standpoint of trapped radiant energy.

  20. PREPARATION AND EVALUATION OF HIGH PURITY BERYLLIUM.

    DTIC Science & Technology

    this work has been devoted recently to the hot swaging of zone refined beryllium. Considerable progress has been made toward the development of hot... swaging schedules capable of producing sound, fine-grained structures in this high pruity laterial. The recovery, recrystallization and grain growth...characteristics of the hot swaged , zone refined beryllium as well as those of hot swaged SR grade Pechiney and commercial grade Berylco beryllium have

  1. Targets for producing high purity I-123

    NASA Technical Reports Server (NTRS)

    Blue, J. W. (Inventor)

    1978-01-01

    Tellurium powder in improved targets is bombarded with a cyclotron beam to produce Xe-123. Flowing gas streams carry the Xe-123 through one cold trap which removes Xe-123 that subsequently decays to I-123. During this bombardment energy is deposited in the target material causing its temperature to rise. Some of the tellurium vaporizes and subsequently condenses on surfaces that are cooler than the vaporization temperature. Provision is made for the repeated bombardment of this condensed tellurium.

  2. High-purity, isotopically enriched bulk silicon

    SciTech Connect

    Ager III, J.W.; Beeman, J.W.; Hansen, W.L.; Haller, E.E.; Sharp, I.D.; Liao, C.; Yang, A.; Thewalt, M.L.W.; Riemann, H.

    2004-11-17

    The synthesis and characterization of dislocation-free, undoped, single crystals of Si enriched in all 3 stable isotopes is reported: {sup 28}Si (99.92%), {sup 29}Si (91.37%), and {sup 30}Si (89.8%). A silane-based process compatible with the relatively small amounts of isotopically enriched precursors that are practically available was used. The silane is decomposed to silicon on a graphite starter rod heated to 700-750 C in a recirculating flow reactor. A typical run produces 35 gm of polycrystalline Si at a growth rates of 5 {micro}m/min and conversion efficiency >95%. Single crystals are grown by the floating zone method and characterized by electrical and optical measurements. Concentrations of shallow dopants (P and B) are as low as mid-10{sup 13} cm{sup -3}. Concentrations of C and O lie below 10{sup 16} and 10{sup 15} cm{sup -3}, respectively.

  3. Ultra high purity, dimensionally stable INVAR 36

    NASA Technical Reports Server (NTRS)

    Sokolowski, Witold M. (Inventor); Lane, Marc S. (Inventor); Odonnell, Timothy P. (Inventor); Hsieh, Cheng H. (Inventor)

    1994-01-01

    An INVAR 36 material having long-term dimensional stability is produced by sintering a blend of powders of nickel and iron under pressure in an inert atmosphere to form an alloy containing less than 0.01 parts of carbon and less than 0.1 part aggregate and preferably 0.01 part individually of Mn, Si, P, S and Al impurities. The sintered alloy is heat treated and slowly and uniformly cooled to form a material having a coefficient of thermal expansion of less than 1 ppm/C and a temporal stability of less than 1 ppm/year.

  4. Ultra high purity, dimensionally stable INVAR 36

    NASA Technical Reports Server (NTRS)

    Sokolowski, Witold M. (Inventor); Lane, Marc S. (Inventor); Hsieh, Cheng H. (Inventor); Odonnell, Timothy P. (Inventor)

    1995-01-01

    An INVAR 36 material having long-term dimensional stability is produced by sintering a blend of powders of nickel and iron under pressure in an inert atmosphere to form an alloy containing less than 0.01 parts of carbon and less than 0.1 part aggregate and preferably 0.01 part individually of Mn, Si, P, S and Al impurities. The sintered alloy is heat treated and slowly and uniformly cooled to form a material having a coefficient of thermal expansion of less than 1 ppm/C and a temporal stability of less than 1 ppm/year.

  5. Ares I-X Flight Test - The Future Begins Here

    NASA Technical Reports Server (NTRS)

    Davis, Stephan R.

    2008-01-01

    In less than two years, the National Aeronautics and Space Administration (NASA) will launch the Ares I-X mission. This will be the first flight of the Ares I crew launch vehicle, which, together with the Ares V cargo launch vehicle, will eventually send humans to the Moon, Mars, and beyond. As the countdown to this first Ares mission continues, personnel from across the Ares I-X Mission Management Office (MMO) are finalizing designs and fabricating vehicle hardware for an April 2009 launch. This paper will discuss the hardware and programmatic progress of the Ares I-X mission. Like the Apollo program, the Ares launch vehicles will rely upon extensive ground, flight, and orbital testing before sending the Orion crew exploration vehicle into space with humans on board. The first flight of Ares I, designated Ares I-X, will be a suborbital development flight test. Ares I-X gives NASA its first opportunity to gather critical data about the flight dynamics of the integrated launch vehicle stack; understand how to control its roll during flight; better characterize the severe stage separation environments that the upper stage engine will experience during future operational flights; and demonstrate the first stage recovery system. NASA also will begin modifying the launch infrastructure and fine-tuning ground and mission operations, as the agency makes the transition from the Space Shuttle to the Ares/Orion system.

  6. Speciation, liquid-liquid extraction, sequential separation, preconcentration, transport and ICP-AES determination of Cr(III), Mo(VI) and W(VI) with calix-crown hydroxamic acid in high purity grade materials and environmental samples.

    PubMed

    Agrawal, Y K; Sharma, K R

    2005-07-15

    A new functionalized calix[6]crown hydroxamic acid is reported for the speciation, liquid-liquid extraction, sequential separation and trace determination of Cr(III), Mo(VI) and W(VI). Chromium(III), molybdenum(VI) and tungsten(VI) are extracted at pH 4.5, 1.5M HCl and 6.0M HCl, respectively with calixcrown hydroxamic acid (37,38,39,40,41,42-hexahydroxy7,25,31-calix[6]crown hydroxamic acid) in chloroform in presence of large number of cations and anions. The extraction mechanism is investigated. The various extraction parameters, appropriate pH/M HCl, choice of solvent, effect of the reagent concentration, temperature and distribution constant have been studied. The speciation, preconcentration and kinetic of transport has been investigated. The maximum transport is observed 35, 45 and 30min for chromium(III), molybdenum(VI) and tungsten(IV), respectively. For trace determination the extracts were directly inserted into the plasma for inductively coupled plasma atomic emission spectrometry, ICP-AES, measurements of chromium, molybdenum and tungsten which increase the sensitivity by 30-fold, with detection limits of 3ngml(-1). The method is applied for the determination of chromium, molybdenum and tungsten in high purity grade ores, biological and environmental samples. The chromium was recovered from the effluent of electroplating industries.

  7. Improved murine glioma detection following modified diet and photobleaching of skin PpIX fluorescence

    NASA Astrophysics Data System (ADS)

    Gibbs, Summer L.; O'Hara, Julia A.; Hoopes, P. Jack; Pogue, Brian W.

    2007-02-01

    The Aminolevulinic Acid (ALA) - Protoporphyrin IX (PpIX) system is unique in the world of photosensitizers in that the prodrug ALA is enzymatically transformed via the tissue of interest into fluorescently detectable levels of PpIX. This system can be used to monitor cellular metabolism of tumor tissue for applications such as therapy monitoring. Detecting PpIX fluorescence noninvasively has proven difficult due to the high levels of PpIX produced in the skin compared to other tissue both with and without ALA administration. In the current study, methods to decrease skin PpIX autofluorescence and skin PpIX fluorescence following ALA administration have been examined. Use of a purified diet is found to decrease both skin PpIX autofluorescence and skin PpIX fluorescence following ALA administration, while addition of a broad spectrum antibiotic to the water shows little effect. Following ALA administration, improved brain tumor detection is seen when skin PpIX fluorescence is photobleached via blue light prior to transmission spectroscopic measurements of tumor bearing and control animals. Both of these methods to decrease skin PpIX autofluorescence and skin PpIX fluorescence following ALA administration are shown to have a large effect on the ability to detect tumor tissue PpIX fluorescence noninvasively in vivo.

  8. Ares I-X: First Flight of a New Era

    NASA Technical Reports Server (NTRS)

    Davis, Stephen R.; Askins, Bruce R.

    2010-01-01

    Since 2005, NASA s Constellation Program has been designing, building, and testing the next generation of launch and space vehicles to carry humans beyond low-Earth orbit (LEO). The Ares Projects at Marshall Space Flight Center (MSFC) are developing the Ares I crew launch vehicle and Ares V cargo launch vehicle. On October 28, 2009, the first development flight test of the Ares I crew launch vehicle, Ares I-X, lifted off from a launch pad at Kennedy Space Center (KSC) on successful suborbital flight. Basing exploration launch vehicle designs on Ares I-X information puts NASA one step closer to full-up "test as you fly," a best practice in vehicle design. Although the final Constellation Program architecture is under review, the Ares I-X data and experience in vehicle design and operations can be applied to any launch vehicle. This paper presents the mission background as well as results and lessons learned from the flight.

  9. Ares I-X: First Flight of a New Generation

    NASA Technical Reports Server (NTRS)

    Davis, Stephan R.; Askins, Bruce R.

    2010-01-01

    The Ares I-X suborbital development flight test demonstrated NASA s ability to design, develop, launch and control a new human-rated launch vehicle (Figure 14). This hands-on missions experience will provide the agency with necessary skills and insights regardless of the future direction of space exploration. The Ares I-X team, having executed a successful launch, will now focus on analyzing the flight data and extracting lessons learned that will be used to support the development of future vehicles.

  10. 75 FR 18245 - Public Federal Regulatory Enforcement Fairness Hearing Region IX Regulatory Fairness Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-09

    ... From the Federal Register Online via the Government Publishing Office SMALL BUSINESS ADMINISTRATION Public Federal Regulatory Enforcement Fairness Hearing Region IX Regulatory Fairness Board.... Small Business Administration (SBA) Region IX Regulatory Fairness Board and the SBA Office of...

  11. Wear behaviour and microstructural characterization of worn surfaces and wear debris of a high purity aluminum and an aluminum-silicon alloy and an aluminum-silicon/silicon carbide composite sliding against an M2 steel

    NASA Astrophysics Data System (ADS)

    Li, Xianyao

    1999-11-01

    The present dissertation discusses wear behavior and microstructural characterization of the wear surface and wear debris of an Al-Si alloy (A356) and an Al-Si (A356) based composite reinforced with 20 vol.% SiC particulate as well as a high purity (99.99%) Al sliding against an M2 steel under unlubricated conditions using a block-on-ring sliding wear tester. It was observed that the wear resistance of the Al-Si/SiCp composite material was superior to that of the Al-Si alloy by one order of magnitude at a low sliding load. It was also observed that the wear resistance of the Al-Si/SiC composite could slightly be increased by approximately 10% due to the T6 beat treatment of the composite. The increase in the wear resistance, however, was not significant when compared to the increase in the hardness of the matrix due to the beat treatment. This can be partially attributed to the fact that in-situ precipitation occurred in the subsurface during the sliding wear of the as-cast Al composites. Microstructural characterization of the worn surfaces and weer debris was carried out by using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) equipped with Energy Dispersive Spectroscopy (EDS), X-ray mapping and X-ray Diffraction (XRD). In particular, longitudinal cross-section TEM analyses of the worn surfaces and wear debris were successfully conducted in the present work. The results showed that the deformed structures in the worn surfaces of the Al-Si alloy and the composite contained a large number of cells and elongated subgrains with an aspect ratio of 5 to 10. It was also observed that mechanically mixed layers (MMLs) were formed during the sliding wear of the Al-Si/SiC composite and Al-Si alloy as well as the high purity (BP) Al against the steel. Characterization of the wear debris by means of the above mentioned techniques and Mossbauer spectroscopy revealed that the wear debris had features similar to those of the MMLs in the worn surfaces

  12. Engineering Streptavidin and a Streptavidin-Binding Peptide with Infinite Binding Affinity and Reversible Binding Capability: Purification of a Tagged Recombinant Protein to High Purity via Affinity-Driven Thiol Coupling

    PubMed Central

    Fogen, Dawson; Wu, Sau-Ching; Ng, Kenneth Kai-Sing; Wong, Sui-Lam

    2015-01-01

    To extend and improve the utility of the streptavidin-binding peptide tag (SBP-tag) in applications ranging from affinity purification to the reversible immobilization of recombinant proteins, a cysteine residue was introduced to the streptavidin mutein SAVSBPM18 and the SBP-tag to generate SAVSBPM32 and SBP(A18C), respectively. This pair of derivatives is capable of forming a disulfide bond through the newly introduced cysteine residues. SAVSBPM32 binds SBP-tag and biotin with binding affinities (Kd ~ 10-8M) that are similar to SAVSBPM18. Although SBP(A18C) binds to SAVSBPM32 more weakly than SBP-tag, the binding affinity is sufficient to bring the two binding partners together efficiently before they are locked together via disulfide bond formation–a phenomenon we have named affinity-driven thiol coupling. Under the condition with SBP(A18C) tags in excess, two SBP(A18C) tags can be captured by a tetrameric SAVSBPM32. The stoichiometry of the disulfide-bonded SAVSBPM32-SBP(A18C) complex was determined using a novel two-dimensional electrophoresis method which has general applications for analyzing the composition of disulfide-bonded protein complexes. To illustrate the application of this reversible immobilization technology, optimized conditions were established to use the SAVSBPM32-affinity matrix for the purification of a SBP(A18C)-tagged reporter protein to high purity. Furthermore, we show that the SAVSBPM32-affinity matrix can also be applied to purify a biotinylated protein and a reporter protein tagged with the unmodified SBP-tag. The dual (covalent and non-covalent) binding modes possible in this system offer great flexibility to many different applications which need reversible immobilization capability. PMID:26406477

  13. 45 CFR 83.5 - Effect of title IX of the Education Amendments of 1972.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 1 2011-10-01 2011-10-01 false Effect of title IX of the Education Amendments of... Purposes; Definitions; Coverage § 83.5 Effect of title IX of the Education Amendments of 1972. The obligations imposed by this part are independent of obligations imposed by or pursuant to title IX of...

  14. 45 CFR 83.5 - Effect of title IX of the Education Amendments of 1972.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 45 Public Welfare 1 2012-10-01 2012-10-01 false Effect of title IX of the Education Amendments of... Purposes; Definitions; Coverage § 83.5 Effect of title IX of the Education Amendments of 1972. The obligations imposed by this part are independent of obligations imposed by or pursuant to title IX of...

  15. 45 CFR 83.5 - Effect of title IX of the Education Amendments of 1972.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 45 Public Welfare 1 2014-10-01 2014-10-01 false Effect of title IX of the Education Amendments of... Purposes; Definitions; Coverage § 83.5 Effect of title IX of the Education Amendments of 1972. The obligations imposed by this part are independent of obligations imposed by or pursuant to title IX of...

  16. 45 CFR 83.5 - Effect of title IX of the Education Amendments of 1972.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 45 Public Welfare 1 2013-10-01 2013-10-01 false Effect of title IX of the Education Amendments of... Purposes; Definitions; Coverage § 83.5 Effect of title IX of the Education Amendments of 1972. The obligations imposed by this part are independent of obligations imposed by or pursuant to title IX of...

  17. Political and Programmatic Impact of Affirmative Action Policy: The Case of Title IX.

    ERIC Educational Resources Information Center

    Bird, Patrick J.

    Title IX legislation has had a widespread impact on institutions of higher education. Similar laws and regulations preceding Title IX include Executive Order 11246, the Comprehensive Health Manpower and Nurse Training Act, and the Equal Employment Opportunity Act. The pervasive influence of Title IX is indicated in its provisions concerning…

  18. 40 CFR Appendix Ix to Part 264 - Ground-Water Monitoring List

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Ground-Water Monitoring List IX... Pt. 264, App. IX Appendix IX to Part 264—Ground-Water Monitoring List Ground-Water Monitoring List... species in the ground water that contain this element are included. 3 CAS index names are those used...

  19. 40 CFR Appendix Ix to Part 264 - Ground-Water Monitoring List

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Ground-Water Monitoring List IX... Pt. 264, App. IX Appendix IX to Part 264—Ground-Water Monitoring List Ground-Water Monitoring List... species in the ground water that contain this element are included. 3 CAS index names are those used...

  20. 40 CFR Appendix Ix to Part 264 - Ground-Water Monitoring List

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 26 2014-07-01 2014-07-01 false Ground-Water Monitoring List IX... Pt. 264, App. IX Appendix IX to Part 264—Ground-Water Monitoring List Ground-Water Monitoring List... species in the ground water that contain this element are included. 3 CAS index names are those used...

  1. 40 CFR Appendix Ix to Part 264 - Ground-Water Monitoring List

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Ground-Water Monitoring List IX... Pt. 264, App. IX Appendix IX to Part 264—Ground-Water Monitoring List Ground-Water Monitoring List... species in the ground water that contain this element are included. 3 CAS index names are those used...

  2. Secondary Athletic Administrators' Perceptions of Title IX Policy Changes

    ERIC Educational Resources Information Center

    Dahl, Gabriel Grawe

    2012-01-01

    The purpose of this study was to investigate North Dakota's Normal Competitive Region (NDNCR) high school athletic administrators' perceptions of 2010 Title IX policy changes respective to their athletic programs. Quantitative and qualitative data were collected to investigate the perceptions. Quantitatively, perception data were gathered from a…

  3. Ares I-X Flight Test Vehicle Modal Test

    NASA Technical Reports Server (NTRS)

    Buehrle, Ralph D.; Templeton, Justin D.; Reaves, Mercedes C.; Horta, Lucas G.; Gaspar, James L.; Bartolotta, Paul A.; Parks, Russel A.; Lazor, Daniel R.

    2010-01-01

    The first test flight of NASA's Ares I crew launch vehicle, called Ares I-X, was launched on October 28, 2009. Ares I-X used a 4-segment reusable solid rocket booster from the Space Shuttle heritage with mass simulators for the 5th segment, upper stage, crew module and launch abort system. Flight test data will provide important information on ascent loads, vehicle control, separation, and first stage reentry dynamics. As part of hardware verification, a series of modal tests were designed to verify the dynamic finite element model (FEM) used in loads assessments and flight control evaluations. Based on flight control system studies, the critical modes were the first three free-free bending mode pairs. Since a test of the free-free vehicle was not practical within project constraints, modal tests for several configurations during vehicle stacking were defined to calibrate the FEM. Test configurations included two partial stacks and the full Ares I-X flight test vehicle on the Mobile Launcher Platform. This report describes the test requirements, constraints, pre-test analysis, test execution and results for the Ares I-X flight test vehicle modal test on the Mobile Launcher Platform. Initial comparisons between pre-test predictions and test data are also presented.

  4. Twenty Years after Title IX: Women in Sports Media.

    ERIC Educational Resources Information Center

    Rubarth, Lisa

    1992-01-01

    Though things are better for women in sports media today, Title IX has barely affected their ability to successfully enter into men's sports reporting. The biggest issue is equal access to locker rooms. Women in sports media face less respect, double standards, lack of support, and salary discrepancy. (SM)

  5. National Environmental/Energy Workforce Assessment for Region IX.

    ERIC Educational Resources Information Center

    National Field Research Center Inc., Iowa City, IA.

    This report represents a detailed summation of existing workforce levels, training programs, career potential, and staffing level projections through 1981 for EPA Region IX. This region serves the states of Arizona, California, Hawaii, and Nevada. The specific pollution programs considered include air, noise, pesticides, potable water, radiation…

  6. Implementing Title IX: Concerns of Undergraduate Physical Education Majors.

    ERIC Educational Resources Information Center

    Bain, Linda L.

    A survey of an equal number of male and female students in the University of Houston's secondary school physical education course articulates prospective teacher concerns regarding the implementation of the nondiscriminatory principles set forth in the Title IX ruling. In general, male students evidence greater overall concern about the ruling's…

  7. Ares I-X Malfunction Turn Range Safety Analysis

    NASA Technical Reports Server (NTRS)

    Beaty, J. R.

    2011-01-01

    Ares I-X was the designation given to the flight test version of the Ares I rocket which was developed by NASA (also known as the Crew Launch Vehicle (CLV) component of the Constellation Program). The Ares I-X flight test vehicle achieved a successful flight test on October 28, 2009, from Pad LC-39B at Kennedy Space Center, Florida (KSC). As part of the flight plan approval for the test vehicle, a range safety malfunction turn analysis was performed to support the risk assessment and vehicle destruct criteria development processes. Several vehicle failure scenarios were identified which could have caused the vehicle trajectory to deviate from its normal flight path. The effects of these failures were evaluated with an Ares I-X 6 degrees-of-freedom (6-DOF) digital simulation, using the Program to Optimize Simulated Trajectories Version II (POST2) simulation tool. The Ares I-X simulation analysis provided output files containing vehicle trajectory state information. These were used by other risk assessment and vehicle debris trajectory simulation tools to determine the risk to personnel and facilities in the vicinity of the launch area at KSC, and to develop the vehicle destruct criteria used by the flight test range safety officer in the event of a flight test anomaly of the vehicle. The simulation analysis approach used for this study is described, including descriptions of the failure modes which were considered and the underlying assumptions and ground rules of the study.

  8. Ares I-X Launch Vehicle Modal Test Overview

    NASA Technical Reports Server (NTRS)

    Buehrle, Ralph D.; Bartolotta, Paul A.; Templeton, Justin D.; Reaves, Mercedes C.; Horta, Lucas G.; Gaspar, James L.; Parks, Russell A.; Lazor, Daniel R.

    2010-01-01

    The first test flight of NASA's Ares I crew launch vehicle, called Ares I-X, is scheduled for launch in 2009. Ares IX will use a 4-segment reusable solid rocket booster from the Space Shuttle heritage with mass simulators for the 5th segment, upper stage, crew module and launch abort system. Flight test data will provide important information on ascent loads, vehicle control, separation, and first stage reentry dynamics. As part of hardware verification, a series of modal tests were designed to verify the dynamic finite element model (FEM) used in loads assessments and flight control evaluations. Based on flight control system studies, the critical modes were the first three free-free bending mode pairs. Since a test of the free-free vehicle is not practical within project constraints, modal tests for several configurations in the nominal integration flow were defined to calibrate the FEM. A traceability study by Aerospace Corporation was used to identify the critical modes for the tested configurations. Test configurations included two partial stacks and the full Ares I-X launch vehicle on the Mobile Launcher Platform. This paper provides an overview for companion papers in the Ares I-X Modal Test Session. The requirements flow down, pre-test analysis, constraints and overall test planning are described.

  9. Methods of producing protoporphyrin IX and bacterial mutants therefor

    SciTech Connect

    Zhou, Jizhong; Qiu, Dongru; He, Zhili; Xie, Ming

    2016-03-01

    The presently disclosed inventive concepts are directed in certain embodiments to a method of producing protoporphyrin IX by (1) cultivating a strain of Shewanella bacteria in a culture medium under conditions suitable for growth thereof, and (2) recovering the protoporphyrin IX from the culture medium. The strain of Shewanella bacteria comprises at least one mutant hemH gene which is incapable of normal expression, thereby causing an accumulation of protoporphyrin IX. In certain embodiments of the method, the strain of Shewanella bacteria is a strain of S. loihica, and more specifically may be S. loihica PV-4. In certain embodiments, the mutant hemH gene of the strain of Shewanella bacteria may be a mutant of shew_2229 and/or of shew_1140. In other embodiments, the presently disclosed inventive concepts are directed to mutant strains of Shewanella bacteria having at least one mutant hemH gene which is incapable of normal expression, thereby causing an accumulation of protoporphyrin IX during cultivation of the bacteria. In certain embodiments the strain of Shewanella bacteria is a strain of S. loihica, and more specifically may be S. loihica PV-4. In certain embodiments, the mutant hemH gene of the strain of Shewanella bacteria may be a mutant of shew_2229 and/or shew_1140.

  10. Gender Equity in Intercollegiate Athletics: Determinants of Title IX Compliance

    ERIC Educational Resources Information Center

    Anderson, Deborah J.; Cheslock, John Jesse; Ehrenberg, Ronald G.

    2006-01-01

    Using new data on intercollegiate athletes, this article shows that recent improvement in Title IX compliance among NCAA Division I institutions was previously overestimated, and provides the first estimates of compliance in Divisions II and III. In addition, regression analyses investigate how institutional characteristics relate to the extent of…

  11. Ares I-X Flight Data Evaluation: Executive Overview

    NASA Technical Reports Server (NTRS)

    Huebner, Lawrence D.; Waits, David A.; Lewis, Donny L.; Richards, James S.; Coates, R. H., Jr.; Cruit, Wendy D.; Bolte, Elizabeth J.; Bangham, Michal E.; Askins, Bruce R.; Trausch, Ann N.

    2011-01-01

    NASA's Constellation Program (CxP) successfully launched the Ares I-X flight test vehicle on October 28, 2009. The Ares I-X flight was a developmental flight test to demonstrate that this very large, long, and slender vehicle could be controlled successfully. The flight offered a unique opportunity for early engineering data to influence the design and development of the Ares I crew launch vehicle. As the primary customer for flight data from the Ares I-X mission, the Ares Projects Office (APO) established a set of 33 flight evaluation tasks to correlate flight results with prospective design assumptions and models. The flight evaluation tasks used Ares I-X data to partially validate tools and methodologies in technical disciplines that will ultimately influence the design and development of Ares I and future launch vehicles. Included within these tasks were direct comparisons of flight data with preflight predictions and post-flight assessments utilizing models and processes being applied to design and develop Ares I. The benefits of early development flight testing were made evident by results from these flight evaluation tasks. This overview provides summary information from assessment of the Ares I-X flight test data and represents a small subset of the detailed technical results. The Ares Projects Office published a 1,600-plus-page detailed technical report that documents the full set of results. This detailed report is subject to the International Traffic in Arms Regulations (ITAR) and is available in the Ares Projects Office archives files.

  12. 40 CFR Appendix Ix to Part 268 - Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B)

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 26 2010-07-01 2010-07-01 false Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B) IX Appendix IX to Part 268 Protection of.... 268, App. IX Appendix IX to Part 268—Extraction Procedure (EP) Toxicity Test Method and...

  13. 40 CFR Appendix Ix to Part 268 - Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B)

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 27 2011-07-01 2011-07-01 false Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B) IX Appendix IX to Part 268 Protection of.... 268, App. IX Appendix IX to Part 268—Extraction Procedure (EP) Toxicity Test Method and...

  14. Enhanced Detection of Low-Abundance Host Cell Protein Impurities in High-Purity Monoclonal Antibodies Down to 1 ppm Using Ion Mobility Mass Spectrometry Coupled with Multidimensional Liquid Chromatography.

    PubMed

    Doneanu, Catalin E; Anderson, Malcolm; Williams, Brad J; Lauber, Matthew A; Chakraborty, Asish; Chen, Weibin

    2015-10-20

    The enormous dynamic range of proteinaceous species present in protein biotherapeutics poses a significant challenge for current mass spectrometry (MS)-based methods to detect low-abundance HCP impurities. Previously, an HCP assay based on two-dimensional chromatographic separation (high pH/low pH) coupled to high-resolution quadrupole time-of-flight (QTOF) mass spectrometry and developed in the author's laboratory has been shown to achieve a detection limit of about 50 ppm (parts per milion) for the identification and quantification of HCPs present in monoclonal antibodies following Protein A purification.1 To improve the HCP detection limit we have explored the utility of several new analytical techniques for HCP analysis and thereby developed an improved liquid chromatography-mass spectrometry (LC-MS) methodology for enhanced detection of HCPs. The new method includes (1) the use of a new charge-surface-modified (CSH) C18 stationary phase to mitigate the challenges of column saturation, peak tailing, and distortion that are commonly observed in the HCP analysis; (2) the incorporation of traveling-wave ion mobility (TWIM) separation of coeluting peptide precursors, and (3) the improvement of fragmentation efficiency of low-abundance HCP peptides by correlating the collision energy used for precursor fragmentation with their mobility drift time. As a result of these improvements, the detection limit of the new methodology was greatly improved, and HCPs present at a concentration as low as 1 ppm (1 ng HCP/mg mAb) were successfully identified and quantified. The newly developed method was applied to analyze two high-purity mAbs (NIST mAb and Infliximab) expressed in a murine cell line. For both samples, low-abundance HCPs (down to 1 ppm) were confidently identified, and the identities of the HCPs were further confirmed by targeted MS/MS experiments. In addition, the performance of the assay was evaluated by an interlaboratory study in which three independent

  15. The Development of the Ares I-X Flight Test

    NASA Technical Reports Server (NTRS)

    Ess, Robert H.

    2008-01-01

    The National Aeronautics and Space Administration (NASA) Constellation Program (CxP) has identified a series of tests to provide insight into the design and development of the Ares I Crew Launch Vehicle (CLV) and the Orion Crew Exploration Vehicle (CEV). Ares I-X was created as the first suborbital development flight test to help meet CxP objectives. The Ares I-X flight vehicle is an early operational model of Ares, with specific emphasis on Ares I and ground operation characteristics necessary to meet Ares I-X flight test objectives. Ares I-X will encompass the design and construction of an entire system that includes the Flight Test Vehicle (FTV) and associated operations. The FTV will be a test model based on the Ares I design. Select design features will be incorporated in the FTV design to emulate the operation of the CLV in order to meet the flight test objectives. The operations infrastructure and processes will be customized for Ares I-X, while still providing data to inform the developers of the launch processing system for Ares/Orion. The FTV is comprised of multiple elements and components that will be developed at different locations. The components will be delivered to the launch/assembly site, Kennedy Space Center (KSC), for assembly of the elements and components into an integrated, flight-ready, launch vehicle. The FTV will fly a prescribed trajectory in order to obtain the necessary data to meet the objectives. Ares I-X will not be commanded or controlled from the ground during flight, but the FTV will be equipped with telemetry systems, a data recording capability and a flight termination system (FTS). The in-flight part of the test includes a trajectory to simulate maximum dynamic pressure during flight and perform a stage separation representative of the CLV. The in-flight test also includes separation of the Upper Stage Simulator (USS) from the First Stage and recovery of the First Stage. The data retrieved from the flight test will be analyzed

  16. Aggressive therapy improves cirrhosis in glycogen storage disease type IX.

    PubMed

    Tsilianidis, Laurie A; Fiske, Laurie M; Siegel, Sara; Lumpkin, Chris; Hoyt, Kate; Wasserstein, Melissa; Weinstein, David A

    2013-06-01

    Glycogen storage disease type IX (GSD IX) is described as a benign condition that often does not require treatment. Most patients with the disease are thought to outgrow the childhood manifestations, which include hepatomegaly, poor growth, and ketosis with or without hypoglycemia. Long term complications including fibrosis and cirrhosis have seldom been reported in the most common subtype, GSD IXα. We present two cases of children with GSD IXα who had fibrosis at the time of diagnosis in addition to the commonly reported disease manifestations. Structured therapy with frequent doses of uncooked cornstarch and protein supplementation was initiated, and both children responded with improved growth velocity, increased energy, decreased hepatomegaly and improved well-being. Additionally, radiographic features of fibrosis improved. We propose that GSD IXα is not a benign condition. Even in patients with a less severe presentation, consideration of a structured treatment regimen to improve quality of life appears warranted.

  17. Bianchi-IX, Darboux-Halphen and Chazy-Ramanujan

    NASA Astrophysics Data System (ADS)

    Chanda, Sumanto; Guha, Partha; Roychowdhury, Raju

    2016-02-01

    Bianchi-IX four metrics are SU(2) invariant solutions of vacuum Einstein equation, for which the connection-wise self-dual case describes the Euler top, while the curvature-wise self-dual case yields the Ricci flat classical Darboux-Halphen system. It is possible to see such a solution exhibiting Ricci flow. The classical Darboux-Halphen system is a special case of the generalized one that arises from a reduction of the self-dual Yang-Mills equation and the solutions to the related homogeneous quadratic differential equations provide the desired metric. A few integrable and near-integrable dynamical systems related to the Darboux-Halphen system and occurring in the study of Bianchi-IX gravitational instanton have been listed as well. We explore in details whether self-duality implies integrability.

  18. Ares I-X Best Estimated Trajectory Analysis and Results

    NASA Technical Reports Server (NTRS)

    Karlgaard, Christopher D.; Beck, Roger E.; Starr, Brett R.; Derry, Stephen D.; Brandon, Jay; Olds, Aaron D.

    2011-01-01

    The Ares I-X trajectory reconstruction produced best estimated trajectories of the flight test vehicle ascent through stage separation, and of the first and upper stage entries after separation. The trajectory reconstruction process combines on-board, ground-based, and atmospheric measurements to produce the trajectory estimates. The Ares I-X vehicle had a number of on-board and ground based sensors that were available, including inertial measurement units, radar, air-data, and weather balloons. However, due to problems with calibrations and/or data, not all of the sensor data were used. The trajectory estimate was generated using an Iterative Extended Kalman Filter algorithm, which is an industry standard processing algorithm for filtering and estimation applications. This paper describes the methodology and results of the trajectory reconstruction process, including flight data preprocessing and input uncertainties, trajectory estimation algorithms, output transformations, and comparisons with preflight predictions.

  19. Ares I-X Thermal Model Correlation and Lessons Learned

    NASA Technical Reports Server (NTRS)

    Amundsen, Ruth M.

    2010-01-01

    The Ares I-X vehicle launched and flew successfully on October 28, 2009. This paper will describe the correlation of the vehicle thermal model to both ground testing and flight data. A main purpose of the vehicle model and ground testing was to ensure that the avionics within the vehicle were held within their thermal limits prior to launch and during flight. The correlation of the avionics box temperatures will be shown. Also, the lessons learned in the thermal discipline during the modeling, test, correlation to test, and flight of the Ares I-X flight test vehicle will be described. Lessons learned will cover thermal modeling, as well as management of the thermal discipline, thermal team, and thermal-related actions in design, testing, and flight.

  20. Hantavirus Prevalence in the IX Region of Chile

    PubMed Central

    Vial, Pablo C.; Castillo, Constanza H.; Godoy, Paula M.; Hjelle, Brian; Ferrés, Marcela G.

    2003-01-01

    An epidemiologic and seroprevalence survey was conducted (n=830) to assess proportion of persons exposed to hantavirus in IX Region Chile, which accounts for 25% of reported cases of hantavirus cardiopulmonary syndrome. This region has three geographic areas with different disease incidences and a high proportion of aboriginals. Serum samples were tested for immunoglobulin (Ig) G antibodies by enzyme-linked immunosorbent assay against Sin Nombre virus N antigen by strip immunoblot assay against Sin Nombre, Puumala, Río Mamoré, and Seoul N antigens. Samples from six patients were positive for IgG antibodies reactive with Andes virus; all patients lived in the Andes Mountains. Foresting was also associated with seropositivity; but not sex, age, race, rodent exposure, or farming activities. Exposure to hantavirus varies in different communities of IX Region. Absence of history of pneumonia or hospital admission in persons with specific IgG antibodies suggests that infection is clinically inapparent. PMID:12890323