WorldWideScience

Sample records for blocking variant surface

  1. Analysis of Separated Flow over Blocked Surface

    Directory of Open Access Journals (Sweden)

    Onur YEMENİCİ

    2013-04-01

    Full Text Available In this study, the separated flow over flat and blocked surfaces was investigated experimentally. Velocity and turbulence intensity measurements were carried out by a constanttemperature hot wire anemometer and static pressure measurements by a micro-manometer. The flow separations and reattachments were occurred before the first block, on the first block, between blocks and after the last block, and the presence of the blocks significantly increased the turbulent intensity

  2. Light extraction block with curved surface

    Science.gov (United States)

    Levermore, Peter; Krall, Emory; Silvernail, Jeffrey; Rajan, Kamala; Brown, Julia J.

    2016-03-22

    Light extraction blocks, and OLED lighting panels using light extraction blocks, are described, in which the light extraction blocks include various curved shapes that provide improved light extraction properties compared to parallel emissive surface, and a thinner form factor and better light extraction than a hemisphere. Lighting systems described herein may include a light source with an OLED panel. A light extraction block with a three-dimensional light emitting surface may be optically coupled to the light source. The three-dimensional light emitting surface of the block may includes a substantially curved surface, with further characteristics related to the curvature of the surface at given points. A first radius of curvature corresponding to a maximum principal curvature k.sub.1 at a point p on the substantially curved surface may be greater than a maximum height of the light extraction block. A maximum height of the light extraction block may be less than 50% of a maximum width of the light extraction block. Surfaces with cross sections made up of line segments and inflection points may also be fit to approximated curves for calculating the radius of curvature.

  3. A block variant of the GMRES method on massively parallel processors

    Energy Technology Data Exchange (ETDEWEB)

    Li, Guangye [Cray Research, Inc., Eagan, MN (United States)

    1996-12-31

    This paper presents a block variant of the GMRES method for solving general unsymmetric linear systems. This algorithm generates a transformed Hessenberg matrix by solely using block matrix operations and block data communications. It is shown that this algorithm with block size s, denoted by BVGMRES(s,m), is theoretically equivalent to the GMRES(s*m) method. The numerical results show that this algorithm can be more efficient than the standard GMRES method on a cache based single CPU computer with optimized BLAS kernels. Furthermore, the gain in efficiency is more significant on MPPs due to both efficient block operations and efficient block data communications. Our numerical results also show that in comparison to the standard GMRES method, the more PEs that are used on an MPP, the more efficient the BVGMRES(s,m) algorithm is.

  4. Surface grafting of poly(L-glutamates). 3. Block copolymerization

    NARCIS (Netherlands)

    Wieringa, RH; Siesling, EA; Werkman, PJ; Vorenkamp, EJ; Schouten, AJ

    2001-01-01

    This paper describes for the first time the synthesis of surface-grafted AB-block copolypeptides, consisting of poly(gamma -benzyl L-glutamate) (PBLG) as the A-block and poly(gamma -methyl L-glutamate) (PMLG) as the B-block. Immobilized primary amine groups of (,gamma -aminopropyl)triethoxysilane

  5. Heat Transfer Enhancement in Turbulent Flows by Blocked Surfaces

    Directory of Open Access Journals (Sweden)

    Onur YEMENİCİ

    2013-04-01

    Full Text Available In this study, the heat transfer analyses over flat and blocked surfaces were carried out in turbulent flow under the influence of the block height. A constant-temperature hot wire anemometer was used to the velocity and turbulent intensity measurements, while temperature values were measured by copper-constantan thermocouples. The average Stanton numbers for block heights of 15 and 25 mm were higher than those of flat surface by %38 and %84, respectively. The results showed that the presence of the blocks increased the heat transfer and the enhancement rose with block heights

  6. Plasma antibodies from malaria-exposed pregnant women recognize variant surface antigens on em>Plasmodium falciparum-infected erythrocytes in a parity-dependent manner and block parasite adhesion to chondroitin sulfate A

    DEFF Research Database (Denmark)

    Ricke, C H; Staalsoe, T; Koram, K

    2000-01-01

    Abs from malaria-exposed multiparous women are able to interfere with binding of P. falciparum parasites to CSA in vitro, and acquisition of Abs interfering with CSA-specific parasite sequestration thus appears to be a critical element in acquired protection against PAM. Here we show that adults from...... an area of hyperendemic P. falciparum transmission generally possessed low levels of Abs specifically recognizing surface Ags expressed by a CSA-adhering parasite isolate, while unselected isolates were well recognized. In marked contrast, most third-trimester pregnant women from that area had very high...

  7. Numbers of center points appropriate to blocked response surface experiments

    Science.gov (United States)

    Holms, A. G.

    1979-01-01

    Tables are given for the numbers of center points to be used with blocked sequential designs of composite response surface experiments as used in empirical optimum seeking. The tables also give the star point radii for exact orthogonal blocking. The center point options vary from a lower limit of one to an upper limit equal to the numbers proposed by Box and Hunter for approximate rotatability and uniform variance, and exact orthogonal blocking. Some operating characteristics of the proposed options are described.

  8. Fibrinogen adsorption on blocked surface of albumin

    DEFF Research Database (Denmark)

    Holmberg, Maria; Hou, Xiaolin

    2011-01-01

    biological samples, including protein solutions. It is based on the assumption that proteins adsorbs as a monolayer on surfaces and that proteins do not adsorb on top of each other. By labelling albumin and fibrinogen with two different radioactive iodine isotopes that emit gamma radiation with different...

  9. A Block Copolymer for Functionalisation of Polymersome Surfaces

    NARCIS (Netherlands)

    van Dongen, Stijn; Nallani, Madhavan; Schoffelen, S.; Cornelissen, Jeroen Johannes Lambertus Maria; Nolte, Roeland; van Hest, Jan

    2008-01-01

    A block copolymer was designed to functionalise the surface of polystyrene-based polymersomes via coaggregation. An α,ω-diacetylene-functionalised poly(ethylene glycol) (PEG) was coupled to an azide-terminated polystyrene via a Cu(I)-catalysed cycloaddition to produce a PS-b-PEG polymer with an

  10. Fabrication of Bioactive Surfaces by Functionalization of Electroactive and Surface-Active Block Copolymers

    Directory of Open Access Journals (Sweden)

    Omotunde Olubi

    2014-08-01

    Full Text Available Biofunctional block copolymers are becoming increasingly attractive materials as active components in biosensors and other nanoscale electronic devices. We have described two different classes of block copolymers with biofuctional properties. Biofunctionality for block copolymers is achieved through functionalization with appropriate biospecific ligands. We have synthesized block copolymers of electroactive poly(3-decylthiophene and 2-hydroxyethyl methacrylate by atom transfer radical polymerization. The block copolymers were functionalized with the dinitrophenyl (DNP groups, which are capable of binding to Immunoglobulin E (IgE on cell surfaces. The block copolymers were shown to be redox active. Additionally, the triblock copolymer of α, ω-bi-biotin (poly(ethylene oxide-b-poly (styrene-b-poly(ethylene oxide was also synthesized to study their capacity to bind fluorescently tagged avidin. The surface-active property of the poly(ethylene oxide block improved the availability of the biotin functional groups on the polymer surfaces. Fluorescence microscopy observations confirm the specific binding of biotin with avidin.

  11. Manipulating Interfaces through Surface Confinement of Poly(glycidyl methacrylate)-block-poly(vinyldimethylazlactone), a Dually Reactive Block Copolymer

    International Nuclear Information System (INIS)

    Lokitz, Bradley S.; Wei, Jifeng; Hinestrosa Salazar, Juan P.; Ivanov, Ilia N.; Browning, James B.; Ankner, John Francis; Kilbey, S. Michael II; Messman, Jamie M.

    2012-01-01

    The assembly of dually reactive, well-defined diblock copolymers incorporating the chemoselective/functional monomer, 4,4-dimethyl-2-vinylazlactone (VDMA) and the surface-reactive monomer glycidyl methacrylate (GMA) is examined to understand how competition between surface attachment and microphase segregation influences interfacial structure. Reaction of the PGMA block with surface hydroxyl groups not only anchors the copolymer to the surface, but limits chain mobility, creating brush-like structures comprising PVDMA blocks, which contain reactive azlactone groups. The block copolymers are spin coated at various solution concentrations and annealed at elevated temperature to optimize film deposition to achieve a molecularly uniform layer. The thickness and structure of the polymer thin films are investigated by ellipsometry, infrared spectroscopy, and neutron reflectometry. The results show that deposition of PGMA-b-PVDMA provides a useful route to control film thickness while preserving azlactone groups that can be further modified with biotin-poly(ethylene glycol)amine to generate designer surfaces. The method described herein offers guidance for creating highly functional surfaces, films, or coatings through the use of dually reactive block copolymers and postpolymerization modification.

  12. The role of Plasmodium falciparum variant surface antigens in protective immunity and vaccine development

    DEFF Research Database (Denmark)

    Hviid, Lars

    2010-01-01

    There is substantial immuno-epidemiological evidence that the parasite-encoded, so-called variant surface antigens (VSAs) such as PfEMP1 on the surface of infected erythrocytes (IEs) are important-in some cases probably decisive-determinants of clinical outcome of P. falciparum malaria. The evide...

  13. Hand grip function assessed by the box and block test is affected by object surfaces.

    Science.gov (United States)

    Seo, Na Jin; Enders, Leah R

    2012-01-01

    N/A. One of the hand function assessment tools is the Box and Block Test (BBT). To examine if the BBT score is affected by grip surfaces. Thirteen adults performed the BBT with wooden, rubber-covered, and paper-covered blocks. The BBT scores and time for seven movements (finger closing, contact to lift-off, transport before barrier, transport after barrier, release, return, and reach) were compared across the three block types. The mean BBT score was 8% higher for the rubber blocks than the paper and wooden blocks (pblock until the block is lifted). Hand function assessments should be controlled for object surfaces. Therapists may vary grip difficulties by changing object surfaces. Redesigning daily objects with high-friction surfaces may increase grip function. N/A. Copyright © 2012 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

  14. Variant surface antigen-specific IgG and protection against clinical consequences of pregnancy-associated Plasmodium falciparum malaria

    DEFF Research Database (Denmark)

    Staalsoe, Trine; Shulman, Caroline E; Bulmer, Judith N

    2004-01-01

    BACKGROUND: Pregnancy-associated malaria caused by Plasmodium falciparum adherence to chondroitin sulfate A in the placental intervillous space is a major cause of low birthweight and maternal anaemia in areas of endemic P falciparum transmission. Adhesion-blocking antibodies that specifically...... recognise parasite-encoded variant surface antigens (VSA) are associated with resistance to pregnancy-associated malaria. We looked for a possible relation between VSA-specific antibody concentrations, placental infection, and protection from low birthweight and maternal anaemia. METHODS: We used flow...... cytometry to measure VSA-specific IgG concentrations in plasma samples taken during child birth from 477 Kenyan women selected from a cohort of 910 women on the basis of HIV-1 status, gravidity, and placental histology. We measured VSA expressed by one placental P falciparum isolate and two isolates...

  15. Variant surface antigen-specific IgG and protection against clinical consequences of pregnancy-associated Plasmodium falciparum malaria

    DEFF Research Database (Denmark)

    Staalsoe, Trine; Shulman, Caroline E; Bulmer, Judith N

    2004-01-01

    BACKGROUND: Pregnancy-associated malaria caused by Plasmodium falciparum adherence to chondroitin sulfate A in the placental intervillous space is a major cause of low birthweight and maternal anaemia in areas of endemic P falciparum transmission. Adhesion-blocking antibodies that specifically...... recognise parasite-encoded variant surface antigens (VSA) are associated with resistance to pregnancy-associated malaria. We looked for a possible relation between VSA-specific antibody concentrations, placental infection, and protection from low birthweight and maternal anaemia. METHODS: We used flow...... selected or not selected for chondroitin sulfate A adhesiveness in-vitro. FINDINGS: Concentrations of plasma IgG specific for VSA, expressed by chondroitin sulfate A-adhering parasites (VSA in pregnancy-associated malaria or vsa-pam), increased with gravidity and were associated with placental histological...

  16. The promoter for a variant surface glycoprotein gene expression site in Trypanosoma brucei

    NARCIS (Netherlands)

    Zomerdijk, J. C.; Ouellette, M.; ten Asbroek, A. L.; Kieft, R.; Bommer, A. M.; Clayton, C. E.; Borst, P.

    1990-01-01

    The variant-specific surface glycoprotein (VSG) gene 221 of Trypanosoma brucei is transcribed as part of a 60 kb expression site (ES). We have identified the promoter controlling this multigene transcription unit by the use of 221 chromosome-enriched DNA libraries and VSG gene 221 expression site

  17. Wrinkle surface instability of an inhomogeneous elastic block with graded stiffness

    Science.gov (United States)

    Yang, Shengyou; Chen, Yi-chao

    2017-04-01

    Surface instabilities have been studied extensively for both homogeneous materials and film/substrate structures but relatively less for materials with continuously varying properties. This paper studies wrinkle surface instability of a graded neo-Hookean block with exponentially varying modulus under plane strain by using the linear bifurcation analysis. We derive the first variation condition for minimizing the potential energy functional and solve the linearized equations of equilibrium to find the necessary conditions for surface instability. It is found that for a homogeneous block or an inhomogeneous block with increasing modulus from the surface, the critical stretch for surface instability is 0.544 (0.456 strain), which is independent of the geometry and the elastic modulus on the surface of the block. This critical stretch coincides with that reported by Biot (1963 Appl. Sci. Res. 12, 168-182. (doi:10.1007/BF03184638)) 53 years ago for the onset of wrinkle instabilities in a half-space of homogeneous neo-Hookean materials. On the other hand, for an inhomogeneous block with decreasing modulus from the surface, the critical stretch for surface instability ranges from 0.544 to 1 (0-0.456 strain), depending on the modulus gradient, and the length and height of the block. This sheds light on the effects of the material inhomogeneity and structural geometry on surface instability.

  18. Self Blocking of CO Dissociation on a Stepped Ruthenium Surface

    DEFF Research Database (Denmark)

    Vendelbo, Søren Bastholm; Johansson, Martin; Mowbray, Duncan

    2010-01-01

    reaction only occurs on the steps. Under ultra high vacuum (UHV) conditions CO dissociates on the step, the oxygen reacts with CO to form CO2 and the residual carbon blocks the step from further CO dissociation. This mechanism competes with the recombination of carbon and oxygen. At high CO pressures, we......The influence of steps on CO reactions has been studied on a Ru(0 1 (1) over bar 5 4) single crystal with a step density of 4%. Based on temperature programmed desorption (TPD) and oxygen titration experiments as well as density functional theory (DFT) calculations, we show that the CO dissociation...... find step blocking no longer dominates the CO dissociation reaction to the same extent and further carbon uptake is observed. This self-poisoning effect is discussed in relation to similar studies of Ni(14 13 13) where such effects were not observed. We find the apparent dissociation energy on the step...

  19. Toothbrushing alters the surface roughness and gloss of composite resin CAD/CAM blocks.

    Science.gov (United States)

    Kamonkhantikul, Krid; Arksornnukit, Mansuang; Lauvahutanon, Sasipin; Takahashi, Hidekazu

    2016-01-01

    This study investigated the surface roughness and gloss of composite resin CAD/CAM blocks after toothbrushing. Five composite resin blocks (Block HC, Cerasmart, Gradia Block, KZR-CAD Hybrid Resin Block, and Lava Ultimate), one hybrid ceramic (Vita Enamic), one feldspar ceramic (Vitablocs Mark II), one PMMA block (Telio CAD), and one conventional composite resin (Filtek Z350 XT) were evaluated. Surface roughness (Ra) and gloss were determined for each group of materials (n=6) after silicon carbide paper (P4000) grinding, 10k, 20k, and 40k toothbrushing cycles. One-way repeated measures ANOVA indicated significant differences in the Ra and gloss of each material except for the Ra of GRA. After 40k toothbrushing cycles, the Ra of BLO and TEL showed significant increases, while CER, KZR, ULT, and Z350 showed significant decreases. GRA, ENA, and VIT maintained their Ra. All of the materials tested, except CER, demonstrated significant decreases in gloss after 40k toothbrushing cycles.

  20. Self-consistent field theory of block copolymers on a general curved surface.

    Science.gov (United States)

    Li, Jianfeng; Zhang, Hongdong; Qiu, Feng

    2014-03-01

    In this work, we propose a theoretical framework based on the self-consistent field theory (SCFT) for the study of self-assembling block copolymers on a general curved surface. Relevant numerical algorithms are also developed. To demonstrate the power of the approach, we calculate the self-assembled patterns of diblock copolymers on three distinct curved surfaces with different genus. We specially study the geometrical effects of curved surfaces on the conformation of polymer chains as well as on the pattern formation of block copolymers. By carefully examining the diffusion equation of the propagator on curved surfaces, it is predicted that Gaussian chains are completely unaware of the extrinsic curvature but that they will respond to the intrinsic curvature of the surface. This theoretical assertion is consistent with our SCFT simulations of block copolymers on general curved surfaces.

  1. Kilohertz Electrical Stimulation Nerve Conduction Block: Effects of Electrode Surface Area.

    Science.gov (United States)

    Patel, Yogi A; Kim, Brian S; Rountree, William S; Butera, Robert J

    2017-10-01

    Kilohertz electrical stimulation (KES) induces repeatable and reversible conduction block of nerve activity and is a potential therapeutic option for various diseases and disorders resulting from pathological or undesired neurological activity. However, successful translation of KES nerve block to clinical applications is stymied by many unknowns, such as the relevance of the onset response, acceptable levels of waveform contamination, and optimal electrode characteristics. We investigated the role of electrode geometric surface area on the KES nerve block threshold using 20- and 40-kHz current-controlled sinusoidal KES. Electrodes were electrochemically characterized and used to characterize typical KES waveforms and electrode charge characteristics. KES nerve block amplitudes, onset duration, and recovery of normal conduction after delivery of the KES were evaluated along with power requirements for effective KES nerve block. Results from this investigation demonstrate that increasing electrode geometric surface area provides for a more power-efficient KES nerve block. Reductions in block threshold by increased electrode surface area were found to be KES-frequency-dependent, with block thresholds and average power consumption reduced by greater than two times with 20-kHz KES waveforms and greater than three times for 40-kHz KES waveforms.

  2. Surface properties of poly(imide-co-siloxane) block copolymers

    Czech Academy of Sciences Publication Activity Database

    Novák, I.; Sysel, P.; Chodák, I.; Špírková, Milena; Janigová, I.

    2009-01-01

    Roč. 103, č. 13 (2009), s76-s78 ISSN 0009-2770. [PMA 2009 &20th SRC . Bratislava, 21.04.2009/23.04.2009] R&D Projects: GA AV ČR IAA100100622; GA AV ČR IAA400500505 Grant - others:Slovak Scientific Agency(SK) VEGA2/7103/27 Institutional research plan: CEZ:AV0Z40500505 Keywords : Poly(imide-siloxane) * surface properties * morphology Subject RIV: CD - Macromolecular Chemistry Impact factor: 0.717, year: 2009 http://www.chemicke-listy.cz/docs/full/2009_13_s058-s081.pdf

  3. Malaria-induced acquisition of antibodies to Plasmodium falciparum variant surface antigens

    DEFF Research Database (Denmark)

    Ofori, Michael F; Dodoo, Daniel; Staalsoe, Trine

    2002-01-01

    In areas of intense Plasmodium falciparum transmission, protective immunity is acquired during childhood in parallel with acquisition of agglutinating antibodies to parasite-encoded variant surface antigens (VSA) expressed on parasitized red blood cells. In a semi-immune child in such an area......, clinical disease is caused mainly by parasites expressing VSA not recognized by preexisting VSA-specific antibodies in that child. Such malaria episodes are known to cause an increase in agglutinating antibodies specifically recognizing VSA expressed by the parasite isolate causing the illness, whereas...... antibody responses to other parasite isolates are relatively unaffected. However, the detailed kinetics of this VSA antibody acquisition are unknown and hence were the aim of this study. We show that P. falciparum malaria in Ghanaian children generally caused a rapid and sustained increase in variant...

  4. Block copolymer-templated chemistry on Si, Ge, InP, and GaAs surfaces.

    Science.gov (United States)

    Aizawa, Masato; Buriak, Jillian M

    2005-06-29

    Patterning of semiconductor surfaces is an area of intense interest, not only for technological applications, such as molecular electronics, sensing, cellular recognition, and others, but also for fundamental understanding of surface reactivity, general control over surface properties, and development of new surface reactivity. In this communication, we describe the use of self-assembling block copolymers to direct semiconductor surface chemistry in a spatially defined manner, on the nanoscale. The proof-of-principle class of reactions evaluated here is galvanic displacement, in which a metal ion, M+, is reduced to M0 by the semiconductor, including Si, Ge, InP, and GaAs. The block copolymer chosen has a polypyridine block which binds to the metal ions and brings them into close proximity with the surface, at which point they undergo reaction; the pattern of resulting surface chemistry, therefore, mirrors the nanoscale structure of the parent block copolymer. This chemistry has the added advantage of forming metal nanostructures that result in an alloy or intermetallic at the interface, leading to strongly bound metal nanoparticles that may have interesting electronic properties. This approach has been shown to be very general, functioning on a variety of semiconductor substrates for both silver and gold deposition, and is being extended to organic and inorganic reactions on a variety of conducting, semiconducting, and insulating substrates.

  5. Orienting Block Copolymer Thin Films via Entropy and Surface Plasma Treatment

    Science.gov (United States)

    Ho, Rong-Ming; Lu, Kai-Yuan; Lo, Ting-Ya; Dehghan, Ashkan; Shi, An-Chang; Prokopios, Georgopanos; Avgeropoulos, Apostolos

    Controlling the orientation of nanostructured thin films of block copolymers (BCPs) is essential for next generation lithography. In the thin-film state, how to achieve the perpendicular orientation of the nanostructured microdomains remains challenging due to the interfacial effects from the air and also the substrate, especially for the blocks with silicon containing segments which usually have different surface energies, favoring parallel microdomain orientation. Here, we show that entropic effect can be used to control the orientation of BCP thin films. Specifically, we used the architecture of star-block copolymers consisting of polystyrene (PS) and poly(dimethylsiloxane) (PDMS) blocks to regulate the entropic contribution to the self-assembled nanostructures. Moreover, we aim to achieve the formation of perpendicular orientation from the air surface via surface plasma treatment to neutralize the interfacial energy difference. By combining the architecture effect (entropy effect) on BCP self-assembly and the surface plasma treatment (enthalpy effect), well-defined perpendicular PDMS microdomains in the PS-b-PDMS thin film can be formed from the bottom of non-neutral substrate and the top of the thin film surface, giving great potential for lithographic applications.

  6. The role of Plasmodium falciparum variant surface antigens in protective immunity and vaccine development

    DEFF Research Database (Denmark)

    Hviid, Lars

    2010-01-01

    that development of PfEMP1-based vaccines to protect specifically against severe malaria syndromes-in particular PAM-is feasible. This review summarizes the evidence that VSAs are important targets of NAI, discusses why VSA-based vaccines might be feasible despite the extensive intra- and interclonal variation...... of VSAs, and how vaccines based on this type of antigens fit into the current global strategy to reduce, eliminate and eventually eradicate the burden of malaria.......There is substantial immuno-epidemiological evidence that the parasite-encoded, so-called variant surface antigens (VSAs), such as PfEMP1 on the surface of infected erythrocytes (IEs) are important-in some cases probably decisive determinants of clinical outcome of P. falciparum malaria...

  7. A robust variant of block Jacobi-Davidson for extracting a large number of eigenpairs: Application to grid-based real-space density functional theory.

    Science.gov (United States)

    Lee, M; Leiter, K; Eisner, C; Breuer, A; Wang, X

    2017-09-21

    In this work, we investigate a block Jacobi-Davidson (J-D) variant suitable for sparse symmetric eigenproblems where a substantial number of extremal eigenvalues are desired (e.g., ground-state real-space quantum chemistry). Most J-D algorithm variations tend to slow down as the number of desired eigenpairs increases due to frequent orthogonalization against a growing list of solved eigenvectors. In our specification of block J-D, all of the steps of the algorithm are performed in clusters, including the linear solves, which allows us to greatly reduce computational effort with blocked matrix-vector multiplies. In addition, we move orthogonalization against locked eigenvectors and working eigenvectors outside of the inner loop but retain the single Ritz vector projection corresponding to the index of the correction vector. Furthermore, we minimize the computational effort by constraining the working subspace to the current vectors being updated and the latest set of corresponding correction vectors. Finally, we incorporate accuracy thresholds based on the precision required by the Fermi-Dirac distribution. The net result is a significant reduction in the computational effort against most previous block J-D implementations, especially as the number of wanted eigenpairs grows. We compare our approach with another robust implementation of block J-D (JDQMR) and the state-of-the-art Chebyshev filter subspace (CheFSI) method for various real-space density functional theory systems. Versus CheFSI, for first-row elements, our method yields competitive timings for valence-only systems and 4-6× speedups for all-electron systems with up to 10× reduced matrix-vector multiplies. For all-electron calculations on larger elements (e.g., gold) where the wanted spectrum is quite narrow compared to the full spectrum, we observe 60× speedup with 200× fewer matrix-vector multiples vs. CheFSI.

  8. Role of Rock Mass Fabric and Faulting in the Development of Block Caving Induced Surface Subsidence

    Science.gov (United States)

    Vyazmensky, Alexander; Elmo, Davide; Stead, Douglas

    2010-09-01

    Extraction of a large volume of ore during block caving can lead to the formation of significant surface subsidence. Current knowledge of the mechanisms that control subsidence development is limited as are our subsidence prediction capabilities. Mining experience suggests that, among other contributing factors, geological structures play a particularly important role in subsidence development. A conceptual modeling study has been undertaken to evaluate the significance of geological structure on surface subsidence. A hybrid finite/discrete element technique incorporating a coupled elasto-plastic fracture mechanics constitutive criterion is adopted; this allows physically realistic modeling of block caving through simulation of the transition from a continuum to a discontinuum. Numerical experiments presented emphasize the importance of joint orientation and fault location on mechanisms of subsidence development and the governing role of geological structure in defining the degree of surface subsidence asymmetry.

  9. Comparison of the Fouling Release Properties of Hydrophobic Fluorinated and Hydrophilic PEGylated Block Copolymer Surfaces

    International Nuclear Information System (INIS)

    Krishnan, S.; Wang, N.; Ober, C.; Finlay, J.; Callow, M.; Callow, J.; Hexemer, A.; Sohn, K.; Kramer, E.; Fischer, D.

    2006-01-01

    To understand the role of surface wettability in adhesion of cells, the attachment of two different marine algae was studied on hydrophobic and hydrophilic polymer surfaces. Adhesion of cells of the diatom Navicula and sporelings (young plants) of the green macroalga Ulva to an underwater surface is mainly by interactions between the surface and the adhesive exopolymers, which the cells secrete upon settlement and during subsequent colonization and growth. Two types of block copolymers, one with poly(ethylene glycol) side-chains and the other with liquid crystalline, fluorinated side-chains, were used to prepare the hydrophilic and hydrophobic surfaces, respectively. The formation of a liquid crystalline smectic phase in the latter inhibited molecular reorganization at the surface, which is generally an issue when a highly hydrophobic surface is in contact with water. The adhesion strength was assessed by the fraction of settled cells (Navicula) or biomass (Ulva) that detached from the surface in a water flow channel with a wall shear stress of 53 Pa. The two species exhibited opposite adhesion behavior on the same sets of surfaces. While Navicula cells released more easily from hydrophilic surfaces, Ulva sporelings showed higher removal from hydrophobic surfaces. This highlights the importance of differences in cell-surface interactions in determining the strength of adhesion of cells to substrates

  10. Modular transformations of conformal blocks in WZW models on Riemann surfaces of higher genus

    International Nuclear Information System (INIS)

    Miao Li; Ming Yu.

    1989-05-01

    We derive the modular transformations for conformal blocks in Wess-Zumino-Witten models on Riemann surfaces of higher genus. The basic ingredient consists of using the Chern-Simons theory developed by Witten. We find that the modular transformations generated by Dehn twists are linear combinations of Wilson line operators, which can be expressed in terms of braiding matrices. It can also be shown that modular transformation matrices for g > 0 Riemann surfaces depend only on those for g ≤ 3. (author). 13 refs, 15 figs

  11. The effect of glazing and aging on the surface properties of CAD/CAM resin blocks.

    Science.gov (United States)

    Tekçe, Neslihan; Fidan, Sinan; Tuncer, Safa; Kara, Dilan; Demirci, Mustafa

    2018-02-01

    To investigate the effect of accelerated aging on surface properties of glazed CAD/CAM resin blocks using a 2D surface profilometer and a 3D non-contact optical profilometer. Three types of CAD/CAM resin restorative materials, LAVA Ultimate (3M ESPE, St Paul, MN, USA), VITA Enamic (Vita Zahnfabrik H. Rauter, Bad Säckingen, Germany), and Cerasmart (GC Corparation, Tokyo, Japan) were used for this study. CAD/CAM blocks were cut in 3-mm thickness slabs and divided into three groups; Group 1: control group (specimens polished with 600 grit SCI paper); Group 2: specimens sandblasted, silanized, and glazed with Optiglaze Color (GC); Group 3: glazed specimens subjected to 5000 thermocycles (n=15). The surface roughness (R a and R z ) was evaluated using a profilometer and a 3D scanning instrument. Data were analyzed using two-way ANOVA and Tukey's post-hoc test ( P .05). For VITA and Cerasmart, the specimens in Group 1 exhibited significantly higher R a values than Group 2 ( P .05). Glaze material Optiglaze Color makes CAD/CAM resin surfaces smooth and glazed CAD/CAM surfaces seem resistant to deterioration under 5000 thermocycles.

  12. Antibodies to variant antigens on the surfaces of infected erythrocytes are associated with protection from malaria in Ghanaian children

    DEFF Research Database (Denmark)

    Dodoo, D; Staalsoe, T; Giha, H

    2001-01-01

    Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) is a variant antigen expressed on the surface of infected erythrocytes. Each parasite genome contains about 40 PfEMP1 genes, but only 1 PfEMP1 gene is expressed at a given time. PfEMP1 serves as a parasite-sequestering ligand to endoth...

  13. A variant surface glycoprotein of Trypanosoma brucei is synthesized with a hydrophobic carboxy-terminal extension from purified glycoprotein.

    NARCIS (Netherlands)

    J.C. Boothroyd; G.A.M. Cross; J.H.J. Hoeijmakers (Jan); P. Borst (Piet)

    1980-01-01

    textabstractSequential expression of variant surface glycoproteins (VSGs) enables the parasitic protozoan Trypanosoma brucei to evade the immune response of its mammalian hosts. Studies of several VSGs, which have been isolated as soluble molecules following disruption of cells in the absence of

  14. Modification of surface wettability through adsorption of partly fluorinated statistical and block polyelectrolytes from aqueous medium.

    Science.gov (United States)

    Nurmi, Leena; Kontturi, Katri; Houbenov, Nikolay; Laine, Janne; Ruokolainen, Janne; Seppälä, Jukka

    2010-10-05

    The wetting properties of electrostatically charged hydrophilic substrates were modified through adsorption of ultrathin layer of amphiphilic block or statistical polyelectrolyte from aqueous medium. The studied polymers were copolymers of 2-(dimethylamino)ethyl methacrylate (DMAEMA) and 2,2,2-trifluoroethyl methacrylate (TFEMA). They were adsorbed on mica from varying pH conditions, either as dissolved unimers or as kinetically trapped aqueous nanoparticles. The structures (by atomic force microscopy) and wetting properties (by dynamic contact angle measurements) of the obtained surface layers were determined. The majority of the surface layers consisted of polymeric nanoparticles with varying surface coverage. Annealing at 150 °C flattened and spread the particles on the surfaces. The surface wettability was found to be significantly influenced by the morphology and chemical composition of the obtained polymeric surface layer. The surfaces with the most homogeneous and smooth polymer layers exhibited the lowest contact angle hysteresis. The advancing/receding contact angles on the most hydrophilic copolymer layer on mica were 47°/cellulose fiber substrates and annealed at 120 °C, highly hydrophobic surfaces were obtained, with advancing contact angles around 160°.

  15. Wafer-Scale Nanopillars Derived from Block Copolymer Lithography for Surface-Enhanced Raman Spectroscopy

    DEFF Research Database (Denmark)

    Li, Tao; Wu, Kaiyu; Rindzevicius, Tomas

    2016-01-01

    We report a novel nanofabrication process via block copolymer lithography using solvent vapor annealing. The nanolithography process is facile and scalable, enabling fabrication of highly ordered periodic patterns over entire wafers as substrates for surface-enhanced Raman spectroscopy (SERS......). Direct silicon etching with high aspect ratio templated by the block copolymer mask is realized without any intermediate layer or external precursors. Uniquely, an atomic layer deposition (ALD)-assisted method is introduced to allow reversing of the morphology relative to the initial pattern. As a result......, highly ordered silicon nanopillar arrays are fabricated with controlled aspect ratios. After metallization, the resulting nanopillar arrays are suitable for SERS applications. These structures readily exhibit an average SERS enhancement factor of above 108, SERS uniformities of 8.5% relative standard...

  16. Surface biofunctionalization of β-TCP blocks using aptamer 74 for bone tissue engineering.

    Science.gov (United States)

    Ardjomandi, N; Huth, J; Stamov, D R; Henrich, A; Klein, C; Wendel, H-P; Reinert, S; Alexander, D

    2016-10-01

    Successful bone regeneration following oral and maxillofacial surgeries depends on efficient functionalization strategies that allow the recruitment of osteogenic progenitor cells at the tissue/implant interface. We have previously identified aptamer 74, which exhibited a binding affinity for osteogenically induced jaw periosteal cells (JPCs). In the present study, this aptamer was used for the surface biofunctionalization of β-tricalcium phosphate (β-TCP) blocks. Atomic force microscopy (AFM) measurements showed increased binding activity of aptamer 74 towards osteogenically induced JPCs compared to untreated controls. The immobilization efficiency of aptamer 74 was analyzed using the QuantiFluor ssDNA assay for 2D surfaces and by amino acid analysis for 3D β-TCP constructs. Following the successful immobilization of aptamer 74 in 2D culture wells and on 3D constructs, in vitro assays showed no significant differences in cell proliferation compared to unmodified surfaces. Interestingly, JPC mineralization was significantly higher on the 2D surfaces and higher cell adhesion was detected on the 3D constructs with immobilized aptamer. Herein, we report an established, biocompatible β-TCP matrix with surface immobilization of aptamer 74, which enhances properties such as cell adhesion on 3D constructs and mineralization on 2D surfaces. Further studies need to be performed to improve the immobilization efficiency and to develop a suitable approach for JPC mineralization growing within 3D β-TCP constructs. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Carboranedithiols: building blocks for self-assembled monolayers on copper surfaces.

    Science.gov (United States)

    Baše, Tomáš; Bastl, Zdeněk; Havránek, Vladimír; Macháček, Jan; Langecker, Jens; Malina, Václav

    2012-08-28

    Two different positional isomers of 1,2-dicarba-closo-dodecaboranedithiols, 1,2-(HS)(2)-1,2-C(2)B(10)H(10) (1) and 9,12-(HS)(2)-1,2-C(2)B(10)H(10) (2), have been investigated as cluster building blocks for self-assembled monolayers (SAMs) on copper surfaces. These two isomers represent a convenient system in which the attachment of SH groups at different positions on the skeleton affects their acidic character and thus also determines their reactivity with a copper surface. Isomer 1 exhibited etching of polycrystalline Cu films, and a detailed investigation of the experimental conditions showed that both the acidic character of SH groups and the presence of oxygen at the copper surface play crucial roles in how the surface reaction proceeds: whether toward a self-assembled monolayer or toward copper film etching. We found that each positional isomer requires completely different conditions for the preparation of a SAM on copper surfaces. Optimized conditions for the former isomer required the exposure of a freshly prepared Cu surface to vapor of 1 in vacuum, which avoided the presence of oxygen and moisture. Adsorption from a dichloromethane solution afforded a sparsely covered Cu(0) surface; isomer 1 effectively removes the surface copper(I) oxide, forming a soluble product, but apparently binds only weakly to the clean Cu(0) surface. In contrast, adsorption of the latter, less volatile isomer proceeded better from a dichloromethane solution than from the vapor phase. Isomer 2 was even able to densely cover the copper surface cleaned up by the dichloromethane solution of 1. Both isomers exhibited high capacity to remove oxygen atoms from the surface copper(I) oxide that forms immediately after the exposure of freshly prepared copper films to ambient atmosphere. Isomer 2 showed suppression of Cu film oxidation. A number of methods including X-ray photoelectron spectroscopy (XPS), X-ray Rutherford back scattering (RBS), proton-induced X-ray emission (PIXE) analysis

  18. Microstructured block copolymer surfaces for control of microbe capture and aggregation

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Ryan R [ORNL; Shubert, Katherine R [ORNL; Morrell, Jennifer L. [University of Tennessee, Knoxville (UTK); Lokitz, Bradley S [ORNL; Doktycz, Mitchel John [ORNL; Retterer, Scott T [ORNL

    2014-01-01

    The capture and arrangement of surface-associated microbes is influenced by biochemical and physical properties of the substrate. In this report, we develop lectin-functionalized substrates containing patterned, three-dimensional polymeric structures of varied shapes and densities and use these to investigate the effects of topology and spatial confinement on lectin-mediated microbe capture. Films of poly(glycidyl methacrylate)-block-4,4-dimethyl-2-vinylazlactone (PGMA-b-PVDMA) were patterned on silicon surfaces into line or square grid patterns with 5 m wide features and varied edge spacing. The patterned films had three-dimensional geometries with 900 nm film thickness. After surface functionalization with wheat germ agglutinin, the size of Pseudomonas fluorescens aggregates captured was dependent on the pattern dimensions. Line patterns with edge spacing of 5 m or less led to the capture of individual microbes with minimal formation of aggregates, while grid patterns with the same spacing also captured individual microbes with further reduction in aggregation. Both geometries allowed for increases in aggregate size distribution with increased in edge spacing. These engineered surfaces combine spatial confinement with affinity-based microbe capture based on exopolysaccharide content to control the degree of microbe aggregation, and can also be used as a platform to investigate intercellular interactions and biofilm formation in microbial populations of controlled sizes.

  19. Surface biofunctionalization of β-TCP blocks using aptamer 74 for bone tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Ardjomandi, N.; Huth, J. [Department of Oral and Maxillofacial Surgery, University Hospital Tübingen (Germany); Stamov, D.R. [JPK Instruments AG, Berlin (Germany); Henrich, A. [Department of Oral and Maxillofacial Surgery, University Hospital Tübingen (Germany); Klein, C. [Dental Practice Zahngesundheit Waiblingen, Waiblingen (Germany); Wendel, H.-P. [Department of Thoracic, Cardiac and Vascular Surgery, University Hospital, Tübingen (Germany); Reinert, S. [Department of Oral and Maxillofacial Surgery, University Hospital Tübingen (Germany); Alexander, D., E-mail: dorothea.alexander@med.uni-tuebingen.de [Department of Oral and Maxillofacial Surgery, University Hospital Tübingen (Germany)

    2016-10-01

    Successful bone regeneration following oral and maxillofacial surgeries depends on efficient functionalization strategies that allow the recruitment of osteogenic progenitor cells at the tissue/implant interface. We have previously identified aptamer 74, which exhibited a binding affinity for osteogenically induced jaw periosteal cells (JPCs). In the present study, this aptamer was used for the surface biofunctionalization of β-tricalcium phosphate (β-TCP) blocks. Atomic force microscopy (AFM) measurements showed increased binding activity of aptamer 74 towards osteogenically induced JPCs compared to untreated controls. The immobilization efficiency of aptamer 74 was analyzed using the QuantiFluor ssDNA assay for 2D surfaces and by amino acid analysis for 3D β-TCP constructs. Following the successful immobilization of aptamer 74 in 2D culture wells and on 3D constructs, in vitro assays showed no significant differences in cell proliferation compared to unmodified surfaces. Interestingly, JPC mineralization was significantly higher on the 2D surfaces and higher cell adhesion was detected on the 3D constructs with immobilized aptamer. Herein, we report an established, biocompatible β-TCP matrix with surface immobilization of aptamer 74, which enhances properties such as cell adhesion on 3D constructs and mineralization on 2D surfaces. Further studies need to be performed to improve the immobilization efficiency and to develop a suitable approach for JPC mineralization growing within 3D β-TCP constructs. - Highlights: • Covalent binding of aptamer 74 on PLGA-coated β-tricalcium phosphate constructs. • AFM analysis of rupture forces between aptamer 74 and jaw periosteal cells. • Analysis of jaw periosteal cell functions on aptamer coated β-TCP constructs.

  20. Maxillary nerve blocks in horses: an experimental comparison of surface landmark and ultrasound-guided techniques.

    Science.gov (United States)

    Stauffer, Stephanie; Cordner, Beckie; Dixon, Jonathon; Witte, Thomas

    2017-07-01

    The aim of this preliminary proof-of-concept study was to evaluate and compare the success and complication rate of infiltration of the maxillary nerve of cadaver heads using previously described surface landmarks, standard ultrasound and a novel needle guidance positioning ultrasound system (SonixGPS). Prospective, anatomical, method-comparison study. Thirty-eight equine cadaver heads. Twenty-six veterinary students performed the three methods consecutively on cadaver heads using an 18 gauge, 8.9 cm spinal needle and 0.5 mL iodinated contrast medium. Computed tomography was used to quantify success (deposition of contrast in contact with the maxillary nerve) and complication rate (contrast identified within surrounding vasculature or periorbital structures) associated with each method. Perineural injection of the maxillary nerve was attempted 76 times, with an overall success rate of 65.8% (50/76) and complication rate of 53.9% (41/76). Success rates were 50% (13/26) with surface landmark, 65.4% (17/26) with standard ultrasound guidance and 83.3% (20/24) with SonixGPS guidance approaches (Fisher's exact test, p=0.046). No significant difference in complication rate was found between the three methods. Ultrasound-guided maxillary nerve blocks were significantly more successful than surface landmark approaches when performed by inexperienced operators, and the highest success rate was achieved with guidance positioning system (GPS) needle guidance. Local anaesthesia of the equine maxillary nerve in the fossa pterygopalatina is frequently used for diagnostic and surgical procedures in the standing sedated horse. Due to vague superficial landmarks with various approaches and the need for experience via ultrasound guidance, this block remains challenging. GPS guidance may improve reliability of maxillary and other nerve blocks, and allow a smaller volume of local anaesthetic solution to be used, thereby improving specificity and reducing the potential for side effects

  1. Xylella fastidiosa outer membrane vesicles modulate plant colonization by blocking attachment to surfaces.

    Science.gov (United States)

    Ionescu, Michael; Zaini, Paulo A; Baccari, Clelia; Tran, Sophia; da Silva, Aline M; Lindow, Steven E

    2014-09-16

    Outer membrane vesicles (OMVs) of Gram-negative bacteria have been studied intensively in recent years, primarily in their role in delivering virulence factors and antigens during pathogenesis. However, the near ubiquity of their production suggests that they may play other roles, such as responding to envelope stress or trafficking various cargoes to prevent dilution or degradation by other bacterial species. Here we show that OMVs produced by Xylella fastidiosa, a xylem-colonizing plant pathogenic bacterium, block its interaction with various surfaces such as the walls of xylem vessels in host plants. The release of OMVs was suppressed by the diffusible signal factor-dependent quorum-sensing system, and a X. fastidiosa ΔrpfF mutant in which quorum signaling was disrupted was both much more virulent to plants and less adhesive to glass and plant surfaces than the WT strain. The higher virulence of the ΔrpfF mutant was associated with fivefold higher numbers of OMVs recovered from xylem sap of infected plants. The frequency of attachment of X. fastidiosa to xylem vessels was 20-fold lower in the presence of OMVs than in their absence. OMV production thus is a strategy used by X. fastidiosa cells to adjust attachment to surfaces in its transition from adhesive cells capable of insect transmission to an "exploratory" lifestyle for systemic spread within the plant host which would be hindered by attachment. OMV production may contribute to the movement of other bacteria in porous environments by similarly reducing their contact with environmental constituents.

  2. Hepatitis B surface antigen variants in voluntary blood donors in Nanjing, China

    Directory of Open Access Journals (Sweden)

    Yong-lin Yang

    2012-04-01

    Full Text Available Abstract Background Hepatitis B virus (HBV is still one of the serious infectious risks for the blood transfusion safety in China. One plausible reason is the emergence of the variants in the major antigenic alpha determinant within the major hydrophilic region (MHR of hepatitis B surface antigen (HBsAg, which have been assumed to evade the immune surveillance and pose a challenge to the disease diagnosis. It is well documented that some commercial ELISA kits could detect the wild-type but not the mutant viruses. The high prevalence of HBV in China also impaired the application of nucleic acid testing (NAT in the improvement of blood security. Molecular epidemiological study of HBsAg variations in China is still limited. This study was designed to identify the prevalence of mutations in the HBsAg in voluntary blood donors in Nanjing, China. Methods A total of 20,326 blood units were enrolled in this study, 39 donors were positive for HBV S gene in the nested-PCR. Mutations in the major hydrophilic region (MHR; aa 99-169 were identified by direct sequencing of S region. Results Among of 20,326 blood units in the Red Cross Transfusion Center of Nanjing from October 2008 to April 2009, 296 samples (1.46%, 296/20,326 were HBsAg positive in the 2 successive rounds of the ELISA test. In these HBsAg positive units, HBV S gene could be successfully amplified from 39 donors (13.18%, 39/296 in the nested-PCR. Sequence analysis revealed that 32 strains (82.1%, 32/39 belong to genotype B, 7 strains (17.9%, 7/39 to genotype C. Besides well known G145R, widely dispersed variations in the MHR of S region, were observed in 20 samples of all the strains sequenced. Conclusions HBV/B and HBV/C are dominant in Nanjing, China. The mutations in the MHR of HBsAg associated with disease diagnosis are common.

  3. Structured nanoporous surfaces from hybrid block copolymer micelle films with metal ions.

    Science.gov (United States)

    Kim, Minsoo P; Kim, Hyeong Jun; Kim, Bumjoon J; Yi, Gi-Ra

    2015-03-06

    We present a novel method for producing structured nanoporous thin films using block copolymer (BCP) micelles loaded with metallic ions. The BCP micellar thin films containing gold (Au) ions were prepared by spin-coating poly(styrene-block-4-vinylpyridine) (PS-b-P4VP) micelle solutions in which Au precursors (AuCl4(-)) were selectively loaded onto the P4VP core. When the micellar films were exposed to cetyltrimethylammonium bromide (CTAB) solutions, the Au precursors were selectively extracted from the P4VP domains due to their strong electrostatic interaction with CTAB, leading to the formation of pores in the micelles. Consequently, regularly patterned nanoporous surfaces were formed. By controlling the molecular weight (Mn) of PS-b-P4VP and the amount of Au precursors (λ) that were loaded in the P4VP domains, the pore size and depth could be tuned precisely. In particular, when a sufficient amount of Au precursors was loaded (λ  ≥ 0.3), the porous surface nanostructure was well developed. In addition, the pore size and depth of the nanostructure increased as the λ value increased. For instance, when the λ value increased from 0.3 to 1.0, the pore size increased from 22.8 nm to 28.8 nm, and the pore depth increased from 2.1 nm to 3.2 nm. Interestingly, the transition from the nonporous structures to the porous structures in the micellar film could be reversibly controlled by adding and removing the Au precursors in the film. Moreover, our method for the preparation of nanoporous films can be extended to micellar film by incorporating other metal ions such as silver (Ag) and iron (Fe).

  4. Nanoscale silicon substrate patterns from self-assembly of cylinder forming poly(styrene)-block-poly(dimethylsiloxane) block copolymer on silane functionalized surfaces.

    Science.gov (United States)

    Borah, Dipu; Cummins, Cian; Rasappa, Sozaraj; Watson, Scott M D; Pike, Andrew R; Horrocks, Benjamin R; Fulton, David A; Houlton, Andrew; Liontos, George; Ntetsikas, Konstantinos; Avgeropoulos, Apostolos; Morris, Michael A

    2017-01-27

    Poly(styrene)-block-poly(dimethylsiloxane) (PS-b-PDMS) is an excellent block copolymer (BCP) system for self-assembly and inorganic template fabrication because of its high Flory-Huggins parameter (χ ∼ 0.26) at room temperature in comparison to other BCPs, and high selective etch contrast between PS and PDMS block for nanopatterning. In this work, self-assembly in PS-b-PDMS BCP is achieved by combining hydroxyl-terminated poly(dimethylsiloxane) (PDMS-OH) brush surfaces with solvent vapor annealing. As an alternative to standard brush chemistry, we report a simple method based on the use of surfaces functionalized with silane-based self-assembled monolayers (SAMs). A solution-based approach to SAM formation was adopted in this investigation. The influence of the SAM-modified surfaces upon BCP films was compared with polymer brush-based surfaces. The cylinder forming PS-b-PDMS BCP and PDMS-OH polymer brush were synthesized by sequential living anionic polymerization. It was observed that silane SAMs provided the appropriate surface chemistry which, when combined with solvent annealing, led to microphase segregation in the BCP. It was also demonstrated that orientation of the PDMS cylinders may be controlled by judicious choice of the appropriate silane. The PDMS patterns were successfully used as an on-chip etch mask to transfer the BCP pattern to underlying silicon substrate with sub-25 nm silicon nanoscale features. This alternative SAM/BCP approach to nanopattern formation shows promising results, pertinent in the field of nanotechnology, and with much potential for application, such as in the fabrication of nanoimprint lithography stamps, nanofluidic devices or in narrow and multilevel interconnected lines.

  5. Surface ECG interatrial block-guided treatment for stroke prevention: rationale for an attractive hypothesis.

    Science.gov (United States)

    Bayés de Luna, Antoni; Martínez-Sellés, Manuel; Bayés-Genís, Antoni; Elosua, Roberto; Baranchuk, Adrian

    2017-07-31

    Atrial fibrillation (AF) is the most common sustained arrhythmia and is associated with stroke, cognitive impairment, and cardiovascular death. Some predisposing factors - as aging, diabetes, hypertension - induce and maintain electrophysiological and ultrastructural remodeling that usually includes fibrosis. Interatrial conduction disturbances play a crucial role in the initiation of atrial fibrosis and in its associated complications. The diagnosis of interatrial blocks (IABs) is easy to perform using the surface ECG. IAB is classified as partial when the P wave duration is ≥120 ms, and advanced if the P wave also presents a biphasic pattern in II, III and aVF. IAB is very frequent in the elderly and, particularly in the case of the advanced type, is associated with AF, AF recurrences, stroke, and dementia. The anticoagulation in elderly patients at high risk of AF without documented arrhythmias is an open issue but recent data suggest that it might have a role, particularly in elderly patients with structural heart disease, high CHA 2 DS 2 VASc (Congestive heart failure/left ventricular dysfunction, Hypertension, Age ≥ 75 [doubled], Diabetes, Stroke [doubled] - Vascular disease, Age 65-74, and Sex category [female]), and advanced IAB. In this debate, we discuss the association of surface ECG IAB, a marker of atrial fibrosis, with AF and stroke. We also present the rationale that justifies further studies regarding anticoagulation in some of these patients.

  6. Ulnar Nerve Conduction Block Using Surface Kilohertz Frequency Alternating Current: A Feasibility Study.

    Science.gov (United States)

    Springer, Shmuel; Kozol, Zvi; Reznic, Zvi

    2018-03-08

    The aim of this study was to test the effects of kilohertz frequency alternating current (KHFAC) surface stimulation applied to the ulnar nerve on force and myoelectrical activity of the abductor digiti minimi (ADM) muscle. Eighteen healthy volunteers (age: 27.6 ± 7.9 years; 10 males, 8 females) were included in the study. Each subject participated in one session during which a biphasic 7 kHz rectangular pulse was delivered above the medial epicondyle of the humerus to induce ulnar nerve blocking. ADM electromyographic (EMG) activity and contraction force were measured before (Pre), immediately after, and following 5 and 10 min post stimulation (post 1, post 2). The results showed that EMG activity decreased immediately after stimulation compared to prestimulation, it returned to the level of prestimulation at 5 min (post 1), and decreased again at 10 min (post 2). Furthermore, analysis of compound adjusted z-score indicated significant decrease of force and myoelectrical activity immediately, and 10 min post stimulation. The findings, which demonstrate that KHFAC surface stimulation of the ulnar nerve may decrease the motor activity of intrinsic hand muscle, can help to develop future methods of neuromodulation to treat hand spasticity. © 2018 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  7. Antisense experiments demonstrate an exon 4 minus splice variant mRNA as the basis for expression of tNOX, a cancer-specific cell surface protein.

    Science.gov (United States)

    Tang, Xiaoyu; Morré, D James; Morré, Dorothy M

    2007-01-01

    A novel hydroquinone and NADH oxidase with protein disulfide-thiol interchange activity (designated ENOX2 or tNOX), associated exclusively with the outer leaflet of the plasma membrane at the surface of cancer cells and in sera of cancer patients, is absent from the surface of noncancer cells and from sera from healthy individuals. Transfection of HeLa (human cervical carcinoma) cells with antisense oligonucleotides and measurement of mRNA levels by real-time quantitative PCR and growth and drug response by in vitro cytotoxicity assays were combined to demonstrate encoding of a cancer-specific and growth-related cell surface protein, tNOX, via an exon 4 minus splice variant. tNOX mRNA levels of HeLa cells were determined following transfection with antisense relative to control cells transfected with Lipofectamine using the cycle threshold method normalized for GAPDH mRNA. Antisense to tNOX exon 4 mRNA blocked generation of full-length tNOX mRNA but not of exon 4 minus mRNA. Antisense to exon 5 mRNA inhibited the production of exon 4 minus mRNA and full-length tNOX mRNA. Scrambled antisense to exon 5 mRNA was without effect. Antisense to exon 5 mRNA decreased the amount of tNOX protein on the surface of cancer cells. As a control, antisense-mediated downregulation of exon 5 minus mRNA of tNOX also was demonstrated as detected using exon 4/exon 6 primers. Exon 5 antisense blocked the cell surface expression of tNOX whereas exon 4 antisense was without effect. In contrast to nontransfected HeLa cells, cells transfected with exon 5 antisense were not inhibited by the green tea catechin, (-)-epigallocatechin-3-gallate. A relationship of tNOX to unregulated growth of cancer cells was provided by data where growth of HeLa cells was inhibited by transfection with the exon 5 antisense oligonucleotides. Growth inhibition was followed by apoptosis in greater than 70% of the transfected cells.

  8. Boundary layers of aqueous surfactant and block copolymer solutions against hydrophobic and hydrophilic solid surfaces

    International Nuclear Information System (INIS)

    Steitz, Roland; Schemmel, Sebastian; Shi Hongwei; Findenegg, Gerhard H

    2005-01-01

    The boundary layer of aqueous surfactants and amphiphilic triblock copolymers against flat solid surfaces of different degrees of hydrophobicity was investigated by neutron reflectometry (NR), grazing incidence small angle neutron scattering (GISANS) and atomic force microscopy (AFM). Solid substrates of different hydrophobicities were prepared by appropriate surface treatment or by coating silicon wafers with polymer films of different chemical natures. For substrates coated with thin films (20-30 nm) of deuterated poly(styrene) (water contact angle θ w ∼ 90), neutron reflectivity measurements on the polymer/water interface revealed a water depleted liquid boundary layer of 2-3 nm thickness and a density about 90% of the bulk water density. No pronounced depletion layer was found at the interface of water against a less hydrophobic polyelectrolyte coating (θ w ∼ 63). It is believed that the observed depletion layer at the hydrophobic polymer/water interface is a precursor of the nanobubbles which have been observed by AFM at this interface. Decoration of the polymer coatings by adsorbed layers of nonionic C m E n surfactants improves their wettability by the aqueous phase at surfactant concentrations well below the critical micellar concentration (CMC) of the surfactant. Here, GISANS experiments conducted on the system SiO 2 /C 8 E 4 /D 2 O reveal that there is no preferred lateral organization of the C 8 E 4 adsorption layers. For amphiphilic triblock copolymers (PEO-PPO-PEO) it is found that under equilibrium conditions they form solvent-swollen brushes both at the air/water and the solid/water interface. In the latter case, the brushes transform to uniform, dense layers after extensive rinsing with water and subsequent solvent evaporation. The primary adsorption layers maintain properties of the precursor brushes. In particular, their thickness scales with the number of ethylene oxide units (EO) of the block copolymer. In the case of dip-coating without

  9. Preparation of ordered silver angular nanoparticles array in block copolymer film for surface-enhanced Raman spectroscopy

    International Nuclear Information System (INIS)

    Svanda, J.; Gromov, M. V.; Kalachyova, Y.; Postnikov, P. S.; Svorcik, V.; Lyutakov, O.

    2016-01-01

    We report a single-step method of preparation of ordered silver nanoparticles array through template-assisted nanoparticles synthesis in the semidried block copolymer film. Ordered nanoparticles were prepared on different substrates by the proper choice of solvents combination and preparation procedure. In particular, block copolymer and silver nitrate were dissolved in the mix of tetrahydrofuran, toluene, and n-methylpyrolidone. During short spin-coating procedure ordering of block copolymer, evaporation of toluene and preferential silver redistribution into poly(4-vinylpyridine) block occurred. Rapid heating of semidry film initiated silver reduction, removing of residual solvent and creation of ordered silver array. After polymer removing silver nanoparticles array was tested as a suitable candidate for subdiffraction plasmonic application–surface-enhanced Raman scattering. Enhancement factor was calculated and compared with the literature data.

  10. Preparation of ordered silver angular nanoparticles array in block copolymer film for surface-enhanced Raman spectroscopy

    Science.gov (United States)

    Svanda, J.; Gromov, M. V.; Kalachyova, Y.; Postnikov, P. S.; Svorcik, V.; Lyutakov, O.

    2016-10-01

    We report a single-step method of preparation of ordered silver nanoparticles array through template-assisted nanoparticles synthesis in the semidried block copolymer film. Ordered nanoparticles were prepared on different substrates by the proper choice of solvents combination and preparation procedure. In particular, block copolymer and silver nitrate were dissolved in the mix of tetrahydrofuran, toluene, and n-methylpyrolidone. During short spin-coating procedure ordering of block copolymer, evaporation of toluene and preferential silver redistribution into poly(4-vinylpyridine) block occurred. Rapid heating of semidry film initiated silver reduction, removing of residual solvent and creation of ordered silver array. After polymer removing silver nanoparticles array was tested as a suitable candidate for subdiffraction plasmonic application-surface-enhanced Raman scattering. Enhancement factor was calculated and compared with the literature data.

  11. Improvement of hand function using different surfaces and identification of difficult movement post stroke in the Box and Block Test.

    Science.gov (United States)

    Slota, Gregory P; Enders, Leah R; Seo, Na Jin

    2014-07-01

    This study determined the impact of changing block surfaces on hand function, as well as identified particularly time-consuming movement components post stroke, measured by the Box and Block Test (BBT). Eight chronic stroke survivors and eight age- and gender-matched control subjects participated in this study. The BBT score (number of blocks moved) and time for seven movement components were compared for three different block surfaces (wood, paper, and rubber). The rubber blocks improved BBT scores 8% (compared to all other conditions) not only for control subjects but also for the paretic and non-paretic hands of stroke survivors, by reducing movement time for finger closing and contact-to-lift. Modifying daily objects' surfaces with rubber could help stroke survivors' hand function. The paretic hand displayed notably slower movement for contact-to-lift, transport-release, reach before barrier, and reach after barrier suggesting that therapies may focus on goal directed reaching and object grasping/releasing. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  12. Occurrence and profiles of organic sun-blocking agents in surface waters and sediments in Japanese rivers and lakes

    Energy Technology Data Exchange (ETDEWEB)

    Kameda, Yutaka, E-mail: kameda.yutaka@pref.saitama.lg.jp [Center for Environmental Science in Saitama, Kamitanadare 914, Kazo 347-0115 (Japan); Kimura, Kumiko; Miyazaki, Motonobu [Saitama City Institute of Health Science and Research, Suzuya 7-5-12, Chuo-ku, Saitama 338-0013 (Japan)

    2011-06-15

    Sun-blocking agents including eight UV filters (UVF) and 10 UV light stabilizers (UVLS) were measured in water and sediment collected from 22 rivers, four sewage treatment plant effluents (STPE) and three lakes in Japan. Total sun blocking agents levels ranged from N.D. to 4928 ng/L and from 2.0 to 3422 {mu}g/kg dry wt in surface water and in sediment, respectively. Benzyl salicylate, benzophenone-3, 2-ethyl hexyl-4-methoxycinnamte (EHMC) and octyl salicylate were dominant in surface water receiving wastewater effluents and STPE, although UV-328, benzophenone and EHMC were dominant in other surface water except background sites. Three UVF and nine UVLS were observed from all sediment and their compositions showed similar patterns with UV-328 and UV-234 as the most prevalent compounds. Homosalate, octocrylene, UV-326, UV-327, UV-328 and UV-234 were significantly correlated with Galaxolide in sediments. Concentrations of UV-327 and UV-328 also had strong correlation between those of UV-326 in sediment. - Highlights: > Total sun-blocking agents levels ranged from N.D. to 4928 ng/L in surface water from 29 sampling sites. > The maximum concentration of total sun-blocking agents was 3422 {mu}g/kg dry wt. in sediment. > Residential wastewaters and STPE were considered to be potential sources of UVLS in river and lakes. > Most of sun-blocking agents in sediment were significantly correlated with HHCB. > UV-326 had a strong linear correlation between UV-327 as well as UV-328 in all sediment. - Occurrence of eight UV filters and 10 UV light stabilizers in surface water and sediment were investigated and characterized their compositions in water and sediment.

  13. Chitosan/polyanion surface modification of styrene–butadiene–styrene block copolymer membrane for wound dressing

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jen Ming, E-mail: jmyang@mail.cgu.edu.tw [Department of Chemical and Materials Engineering, Chang Gung University, Kwei-Shan, Tao-Yuan 333, Taiwan (China); Yang, Jhe-Hao [Department of Electronic Engineering, Chang Gung University, Kwei-Shan, Tao-Yuan 333, Taiwan (China); Huang, Huei Tsz [Department of Chemical and Materials Engineering, Chang Gung University, Kwei-Shan, Tao-Yuan 333, Taiwan (China)

    2014-01-01

    The surface of styrene–butadiene–styrene block copolymer (SBS) membrane is modified with tri-steps in this study. At first, two step modified SBS membrane (MSBS) was prepared with epoxidation and ring opening reaction with maleated ionomer. Then chitosan was used as the polycation electrolyte and sodium alginate, poly(γ-glutamic acid) (PGA) and poly(aspartic acid) (PAsp) were selected as polyanion electrolytes to deposit on the surfaces of MSBS membrane by the layer-by-layer self-assembly (LbL) deposition technique to get three [chitosan/polyanion] LbL modified SBS membranes, ([CS/Alg], [CS/PGA] and [CS/PAsp]). From the quantitative XPS analysis and water contact angle measurement, it is found that the order of wettability and the content of functional group percentages of COO{sup −} and -O=C-N- on the three [CS/polyanion] systems are [CS/Alg] > [CS/PGA] > [CS/PAsp]. Performances of water vapor transmission rates, fibronectin adsorption, antibacterial assessment and 3T3 fibroblast cell growth on [CS/Alg], [CS/PGA] and [CS/PAsp] membranes were also evaluated. With the evaluation of water vapor transmission rate, these [CS/Alg], [CS/PGA] and [CS/PAsp] membranes are sterile semipermeable with water evaporation at about 82 ± 8 g/day · m{sup 2}. It is found that the amount of fibronectin adsorption on the three [CS/polyanion] systems is significantly determined by the sum of the functional group of COO{sup −} and -O=C-N- on the surfaces of [CS/Alg], [CS/PGA] and [CS/PAsp] systems. The results are inverse with the sum of the functional group of COO{sup −} and -O=C-N- on the three [CS/polyanion]. From the cytotoxicity test and cell adhesion and proliferation assay of 3T3 fibroblasts on the three [CS/polyanion] systems, it revealed that the cells not only remained viable but they also proliferated on the surfaces of [CS/Alg], [CS/PGA] and [CS/PAsp]. The bactericidal activity was found on [CS/Alg], [CS/PGA] and [CS/PAsp]. The transport of bacterial through

  14. Identifying the nature of surface chemical modification for directed self-assembly of block copolymers

    Directory of Open Access Journals (Sweden)

    Laura Evangelio

    2017-09-01

    Full Text Available In recent years, block copolymer lithography has emerged as a viable alternative technology for advanced lithography. In chemical-epitaxy-directed self-assembly, the interfacial energy between the substrate and each block copolymer domain plays a key role on the final ordering. Here, we focus on the experimental characterization of the chemical interactions that occur at the interface built between different chemical guiding patterns and the domains of the block copolymers. We have chosen hard X-ray high kinetic energy photoelectron spectroscopy as an exploration technique because it provides information on the electronic structure of buried interfaces. The outcome of the characterization sheds light onto key aspects of directed self-assembly: grafted brush layer, chemical pattern creation and brush/block co-polymer interface.

  15. Plasmodium falciparum variant surface antigen expression varies between isolates causing severe and nonsevere malaria and is modified by acquired immunity

    DEFF Research Database (Denmark)

    Nielsen, Morten A; Staalsoe, Trine; Kurtzhals, Jørgen

    2002-01-01

    of immunity, as disease-causing parasites appear to be those not controlled by preexisting VSA-specific Abs. In this work we report that VSA expressed by parasites from young Ghanaian children with P. falciparum malaria were commonly and strongly recognized by plasma Abs from healthy children in the same area......, and that the VSA expression pattern is modulated by immunity. This opens the possibility of developing morbidity-reducing vaccines targeting a limited subset of common and particularly virulent VSA.......In areas of endemic parasite transmission, protective immunity to Plasmodium falciparum malaria is acquired over several years with numerous disease episodes. Acquisition of Abs to parasite-encoded variant surface Ags (VSA) on the infected erythrocyte membrane is important in the development...

  16. Glucocorticoid-regulated and constitutive trafficking of proteolytically processed cell surface-associated glycoproteins in wild type and variant rat hepatoma cells

    International Nuclear Information System (INIS)

    Amacher, S.L.; Goodman, L.J.; Bravo, D.A.; Wong, K.Y.; Goldfine, I.D.; Hawley, D.M.; Firestone, G.L.

    1989-01-01

    Glucocorticoids regulate the trafficking of mouse mammary tumor virus (MMTV) glycoproteins to the cell surface in the rat hepatoma cell line M1.54, but not in the immunoselected sorting variant CR4. To compare the localization of MMTV glycoproteins to another proteolytically processed glycoprotein, both wild type M1.54 cells and variant CR4 cells were transfected with a human insulin receptor (hIR) expression vector, pRSVhIR. The production of cell surface hIR was monitored in dexamethasone-treated and -untreated wild type M1.54 and variant CR4 cells by indirect immunofluorescence, direct plasma membrane immunoprecipitation, and by [125I] insulin binding. In both wild type and variant rat hepatoma cells, hIR were localized at the cell surface in the presence or in the absence of 1 microM dexamethasone. In contrast, the glucocorticoid-regulated trafficking of cell surface MMTV glycoproteins occurred only in wild type M1.54 cells. We conclude that the hIR, which undergoes posttranslational processing reactions similar to MMTV glycoproteins, does not require glucocorticoids to be transported to the plasma membrane and is representative of a subset of cell surface glycoproteins whose trafficking is constitutive in rat hepatoma cells. Thus, MMTV glycoproteins and hIR provide specific cell surface markers to characterize the glucocorticoid-regulated and constitutive sorting pathways

  17. Variants of a Leishmania surface antigen derived from a multigenic family.

    Science.gov (United States)

    Murray, P J; Spithill, T W

    1991-12-25

    The promastigote surface antigen-2 (PSA-2) complex comprises a group of immunogenic surface antigens linked to the surface of the Leishmania major promastigote with glycosylphosphatidylinositol anchors. The L. major genome contains at least 14 PSA-2 genes on a 950-kilobase chromosome and comprising approximately 20% of the length of this chromosome. The sequence of three independent, but incomplete, PSA-2 cDNAs and one genomic fragment encoding a complete PSA-2 coding sequence were compared. PSA-2 genes encode polypeptides exhibiting 22-25aa tandem repeat elements, threonine-rich segments which vary between genes, a conserved COOH-terminal cysteine-rich region, and a conserved GPI anchor signal sequence. PSA-2 genes appear to be transcribed in a complex manner with multiple RNAs. The complex genomic organization of PSA-2 genes is present in other members of the genus suggesting that PSA-2 function is important for the biology of Leishmania.

  18. Variant of a volume-of-fluid method for surface tension-dominant two ...

    Indian Academy of Sciences (India)

    2016-08-26

    Aug 26, 2016 ... The capabilities of the volume-of-fluid method for the calculation of surface tension-dominant two-phase flows are explained. The accurate calculation of the interface remains a problem for the volume-of-fluid method if the density ratios of the fluids in different phases are high. The simulations of bubble ...

  19. Modification of polylactide surfaces with lactide-ethylene oxide functional block copolymers: Accessibility of functional groups

    Czech Academy of Sciences Publication Activity Database

    Třesohlavá, Eliška; Popelka, Štěpán; Machová, Luďka; Rypáček, František

    2010-01-01

    Roč. 11, č. 1 (2010), s. 68-75 ISSN 1525-7797 R&D Projects: GA AV ČR 1QS500110564 Institutional research plan: CEZ:AV0Z40500505 Keywords : polylactide * poly(lactide)-block-poly( ethylene oxide ) * biomimetic Subject RIV: CD - Macromolecular Chemistry Impact factor: 5.327, year: 2010

  20. Functionalized surfaces of polylactide modified by Langmuir-Blodgett films of amphiphilic block copolymers

    Czech Academy of Sciences Publication Activity Database

    Kubies, Dana; Machová, Luďka; Brynda, Eduard; Lukáš, Jaromír; Rypáček, František

    2003-01-01

    Roč. 14, č. 2 (2003), s. 143-149 ISSN 0957-4530 R&D Projects: GA ČR GA203/99/0576 Institutional research plan: CEZ:AV0Z4050913 Keywords : polylactide * Langmuir - Blodgett films * amphiphilic block copolymers Subject RIV: CD - Macromolecular Chemistry Impact factor: 0.930, year: 2003

  1. Nanoparticle-cell interactions: surface chemistry effects on the cellular uptake of biocompatible block copolymer assemblies

    Czech Academy of Sciences Publication Activity Database

    de Castro, C. E.; Ribeiro, C. A. S.; Alavarse, A. C.; Albuquerque, L. J. C.; da Silva, M. C. C.; Jäger, Eliezer; Surman, František; Schmidt, V.; Giacomelli, C.; Giacomelli, F. C.

    2018-01-01

    Roč. 34, č. 5 (2018), s. 2180-2188 ISSN 0743-7463 R&D Projects: GA ČR(CZ) GA17-09998S Institutional support: RVO:61389013 Keywords : biocompatibility * block copolymers * controlled drug delivery Subject RIV: CD - Macromolecular Chemistry OBOR OECD: Polymer science Impact factor: 3.833, year: 2016

  2. Blocking protein farnesylation improves nuclear shape abnormalities in keratinocytes of mice expressing the prelamin A variant in Hutchinson-Gilford progeria syndrome

    OpenAIRE

    Wang, Yuexia; Östlund, Cecilia; Worman, Howard J

    2010-01-01

    Hutchinson-Gilford progeria syndrome (HGPS) is an accelerated aging disorder caused by mutations in LMNA leading to expression of a truncated prelamin A variant termed progerin. Whereas a farnesylated polypeptide is normally removed from the carboxyl-terminus of prelamin A during endoproteolytic processing to lamin A, progerin lacks the cleavage site and remains farnesylated. Cultured cells from human subjects with HGPS and genetically modified mice expressing progerin have nuclear morphologi...

  3. Analysis of cosmid clones of nuclear DNA from Trypanosome brucei shows that the genes for variant surface glycoproteins are clustered in the genome.

    NARCIS (Netherlands)

    D. Valerio (Dinko); T. de Lange; P. Borst (Piet); F.G. Grosveld (Frank); L.H.T. van der Ploeg

    1982-01-01

    textabstractTrypanosoma brucei contains more than a hundred genes coding for the different variant surface glycoproteins (VSGs). Activation of some of these genes involves the duplication of the gene (the basic copy or BC) and transposition of the duplicate to an expression site (yielding the

  4. Plasmodium falciparum parasites expressing pregnancy-specific variant surface antigens adhere strongly to the choriocarcinoma cell line BeWo

    DEFF Research Database (Denmark)

    Haase, Rikke N; Megnekou, Rosette; Lundquist, Maja

    2006-01-01

    Placenta-sequestering Plasmodium falciparum parasites causing pregnancy-associated malaria express pregnancy-specific variant surface antigens (VSA(PAM)). We report here that VSA(PAM)-expressing patient isolates adhere strongly to the choriocarcinoma cell line BeWo and that the BeWo line can...... be used to efficiently select for VSA(PAM) expression in vitro....

  5. Expression of variant surface antigens by Plasmodium falciparum parasites in the peripheral blood of clinically immune pregnant women indicates ongoing placental infection

    DEFF Research Database (Denmark)

    Ofori, Michael F; Staalsoe, Trine; Bam, Victoria

    2003-01-01

    Placenta-sequestered Plasmodium falciparum parasites that cause pregnancy-associated malaria (PAM) in otherwise clinically immune women express distinct variant surface antigens (VSA(PAM)) not expressed by parasites in nonpregnant individuals. We report here that parasites from the peripheral blood...

  6. Human T-cell recognition of synthetic peptides representing conserved and variant sequences from the merozoite surface protein 2 of Plasmodium falciparum

    DEFF Research Database (Denmark)

    Theander, T G; Hviid, L; Dodoo, D

    1997-01-01

    Merozoite surface protein 2 (MSP2) is a malaria vaccine candidate currently undergoing clinical trials. We analyzed the peripheral blood mononuclear cell (PBMC) response to synthetic peptides corresponding to conserved and variant regions of the FCQ-27 allelic form of MSP2 in Ghanaian individuals...

  7. Surface biology of collagen scaffold explains blocking of wound contraction and regeneration of skin and peripheral nerves.

    Science.gov (United States)

    Yannas, I V; Tzeranis, D; So, P T

    2015-12-23

    We review the details of preparation and of the recently elucidated mechanism of biological (regenerative) activity of a collagen scaffold (dermis regeneration template, DRT) that has induced regeneration of skin and peripheral nerves (PN) in a variety of animal models and in the clinic. DRT is a 3D protein network with optimized pore size in the range 20-125 µm, degradation half-life 14 ± 7 d and ligand densities that exceed 200 µM α1β1 or α2β1 ligands. The pore has been optimized to allow migration of contractile cells (myofibroblasts, MFB) into the scaffold and to provide sufficient specific surface for cell-scaffold interaction; the degradation half-life provides the required time window for satisfactory binding interaction of MFB with the scaffold surface; and the ligand density supplies the appropriate ligands for specific binding of MFB on the scaffold surface. A dramatic change in MFB phenotype takes place following MFB-scaffold binding which has been shown to result in blocking of wound contraction. In both skin wounds and PN wounds the evidence has shown clearly that contraction blocking by DRT is followed by induction of regeneration of nearly perfect organs. The biologically active structure of DRT is required for contraction blocking; well-matched collagen scaffold controls of DRT, with structures that varied from that of DRT, have failed to induce regeneration. Careful processing of collagen scaffolds is required for adequate biological activity of the scaffold surface. The newly understood mechanism provides a relatively complete paradigm of regenerative medicine that can be used to prepare scaffolds that may induce regeneration of other organs in future studies.

  8. Lectin-functionalized poly(glycidyl methacrylate)-block-poly(vinyldimethyl azlactone) surface supports for high avidity microbial capture

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Ryan R [ORNL; Hinestrosa Salazar, Juan P [ORNL; Shubert, Katherine R [ORNL; Morrell, Jennifer L. [University of Tennessee, Knoxville (UTK); Pelletier, Dale A [ORNL; Messman, Jamie M [ORNL; Kilbey, II, S Michael [ORNL; Lokitz, Bradley S [ORNL; Retterer, Scott T [ORNL

    2013-01-01

    Microbial exopolysaccharides (EPS) play a critical and dynamic role in shaping the interactions between microbial community members and their local environment. The capture of targeted microbes using surface immobilized lectins that recognize specific extracellular oligosaccharide moieties offers a non-destructive method for functional characterization based on EPS content. In this report, we evaluate the use of the block co-polymer, poly(glycidyl methacrylate)-block-4,4-dimethyl-2-vinylazlactone (PGMA-b-PVDMA), as a surface support for lectin-specific microbial capture. Arrays of circular polymer supports ten micron in diameter were generated on silicon substrates to provide discrete, covalent coupling sites for Triticum vulgare and Lens culinaris lectins. These supports promoted microbe adhesion and colony formation in a lectin-specific manner. Silicon posts with similar topography containing only physisorbed lectins showed significantly less activity. These results demonstrate that micropatterned PGMA-b-PVDMA supports provide a unique platform for microbial capture and screening based on EPS content by combining high avidity lectin surfaces with three-dimensional topography.

  9. Surface Modification for Controlling the Orientation of Block Copolymers in thin film and in Cylindrical Nanopores

    Science.gov (United States)

    Lin, Xin-Guan; Lin, Feng-Cheng; Tung, Shih-Huang

    2012-02-01

    A series of benzocyclobutene-functionalized random copolymers of styrene and 4-vinylpyridine were synthesized by nitroxide-mediated controlled radical polymerization with BPO and TEMPO. Our research was to use these random copolymers of P(S-r-BCB-r-4VP) to control the orientation of microdomains in block copolymers(BCPs) of poly(styrene-b-4-vinylpyridine)(PS-b-P4VP) thin films and in cylindrical nanopores of anodized aluminum oxide (AAO) membranes. On P(S-r-BCB-r-4VP)-modified substrate,we found that in some particular compositions of random copolymer ,the parallel orientation of the microdomains is switched to be perpendicular in PS-b-P4VP thin film. We also introduced P(S-r-BCB-r-4VP) solution into the nanopores of the AAO and nanotubes formed after solvent evaporation and pyrolysis. And then BCPs of PS-b-P4VP were drawn into the P(S-r-BCB-r-4VP)-modified nanopores in the melt via capillary action to form P(S-r-BCB-r-4VP) coated nanorods of PS-b-P4VP.Similarly,in some particular compositions of random copolymer, we observed that the interactions of the blocks with the walls are not strong or if the interactions are balanced, then the orientation of the microdomains will change from being parallel to being perpendicular to the confining walls.

  10. Evolutionary structure of Plasmodium falciparum major variant surface antigen genes in South America: Implications for epidemic transmission and surveillance.

    Science.gov (United States)

    Rougeron, Virginie; Tiedje, Kathryn E; Chen, Donald S; Rask, Thomas S; Gamboa, Dionicia; Maestre, Amanda; Musset, Lise; Legrand, Eric; Noya, Oscar; Yalcindag, Erhan; Renaud, François; Prugnolle, Franck; Day, Karen P

    2017-11-01

    Strong founder effects resulting from human migration out of Africa have led to geographic variation in single nucleotide polymorphisms (SNPs) and microsatellites (MS) of the malaria parasite, Plasmodium falciparum . This is particularly striking in South America where two major founder populations of P. falciparum have been identified that are presumed to have arisen from the transatlantic slave trade. Given the importance of the major variant surface antigen of the blood stages of P. falciparum as both a virulence factor and target of immunity, we decided to investigate the population genetics of the genes encoding " Plasmodium falciparum Erythrocyte Membrane Protein 1" ( Pf EMP1) among several countries in South America, in order to evaluate the transmission patterns of malaria in this continent. Deep sequencing of the DBLα domain of var genes from 128 P. falciparum isolates from five locations in South America was completed using a 454 high throughput sequencing protocol. Striking geographic variation in var DBLα sequences, similar to that seen for SNPs and MS markers, was observed. Colombia and French Guiana had distinct var DBLα sequences, whereas Peru and Venezuela showed an admixture. The importance of such geographic variation to herd immunity and malaria vaccination is discussed.

  11. Blocked-micropores, surface functionalized, bio-compatible and silica-coated iron oxide nanocomposites as advanced MRI contrast agent

    International Nuclear Information System (INIS)

    Darbandi, Masih; Laurent, Sophie; Busch, Martin; Li Zian; Yuan Ying; Krüger, Michael; Farle, Michael; Winterer, Markus; Vander Elst, Luce; Muller, Robert N.; Wende, Heiko

    2013-01-01

    Biocompatible magnetic nanoparticles have been found promising in several biomedical applications for tagging, imaging, sensing and separation in recent years. In this article, a systematic study of the design and development of surface-modification schemes for silica-coated iron oxide nanoparticles (IONP) via a one-pot, in situ method at room temperature is presented. Silica-coated IONP were prepared in a water-in-oil microemulsion, and subsequently the surface was modified via addition of organosilane reagents to the microemulsion system. The structure and the morphology of the as synthesized nanoparticles have been investigated by means of transmission electron microscopy (TEM) and measurement of N 2 adsorption–desorption. Electron diffraction and high-resolution transmission electron microscopic (TEM) images of the nanoparticles showed the highly crystalline nature of the IONP structures. Nitrogen adsorption indicates microporous and blocked-microporous structures for the silica-coated and amine functionalized silica-coated IONP, respectively which could prove less cytotoxicity of the functionalized final product. Besides, the colloidal stability of the final product and the presence of the modified functional groups on top of surface layer have been proven by zeta-potential measurements. Owing to the benefit from the inner IONP core and the hydrophilic silica shell, the as-synthesized nanocomposites were exploited as an MRI contrast enhancement agent. Relaxometric results prove that the surface functionalized IONP have also signal enhancement properties. These surface functionalized nanocomposites are not only potential candidates for highly efficient contrast agents for MRI, but could also be used as ultrasensitive biological-magnetic labels, because they are in nanoscale size, having magnetic properties, blocked-microporous and are well dispersible in biological environment.

  12. On-surface covalent linking of organic building blocks on a bulk insulator.

    Science.gov (United States)

    Kittelmann, Markus; Rahe, Philipp; Nimmrich, Markus; Hauke, Christopher M; Gourdon, André; Kühnle, Angelika

    2011-10-25

    On-surface synthesis in ultrahigh vacuum provides a promising strategy for creating thermally and chemically stable molecular structures at surfaces. The two-dimensional confinement of the educts, the possibility of working at higher (or lower) temperatures in the absence of solvent, and the templating effect of the surface bear the potential of preparing compounds that cannot be obtained in solution. Moreover, covalently linked conjugated molecules allow for efficient electron transport and are, thus, particularly interesting for future molecular electronics applications. When having these applications in mind, electrically insulating substrates are mandatory to provide sufficient decoupling of the molecular structure from the substrate surface. So far, however, on-surface synthesis has been achieved only on metallic substrates. Here we demonstrate the covalent linking of organic molecules on a bulk insulator, namely, calcite. We deliberately employ the strong electrostatic interaction between the carboxylate groups of halide-substituted benzoic acids and the surface calcium cations to prevent molecular desorption and to reach homolytic cleavage temperatures. This allows for the formation of aryl radicals and intermolecular coupling. By varying the number and position of the halide substitution, we rationally design the resulting structures, revealing straight lines, zigzag structures, and dimers, thus providing clear evidence for the covalent linking. Our results constitute an important step toward exploiting on-surface synthesis for molecular electronics and optics applications, which require electrically insulating rather than metallic supporting substrates.

  13. Optimisation of Surface-Initiated Photoiniferter-Mediated Polymerisation under Confinement, and the Formation of Block Copolymers in Mesoporous Films

    Directory of Open Access Journals (Sweden)

    Jessica C. Tom

    2017-10-01

    Full Text Available Nature as the ultimate inspiration can direct, gate, and selectively transport species across channels to fulfil a specific targeted function. Harnessing such precision over local structure and functionality at the nanoscale is expected to lead to indispensable developments in synthetic channels for application in catalysis, filtration and sensing, and in drug delivery. By combining mesoporous materials with localised charge-switchable poly(2-(dimethylaminoethyl methacrylate (PDMAEMA brushes, precisely controlling pore filling and exploring the possibility of incorporating two different responsive polymers, we hope to approach the precision control of natural systems in the absence of an external force. Here, we report a simple one-step approach to prepare a mesoporous silica thin film with ~8 nm pores functionalised with a photoiniferter by combining sol–gel chemistry and evaporation-induced self-assembly (EISA. We show that surface-initiated photoiniferter-mediated polymerisation (SI-PIMP allows the incorporation of a high polymer content up to geometrical pore blocking by the simple application of UV light in the presence of a monomer and solvent, proceeding in a controlled manner in pore sizes below 10 nm, with the potential to tune the material properties through the formation of surface-grafted block copolymers.

  14. NEXAFS Depth Profiling of Surface Segregation in Block Copolymer Thin Films

    Science.gov (United States)

    2010-01-01

    filtered using a 450 nm syringe filter and spin -coated on silicon wafers. A Cee model 100CB spin coater was used at a rotational speed of 2000 rpm for 30 s...at the surface is of thermodynamic origin or of kinetic origin (that is, dependent on polarity of the solvent used for spin coating, solvent

  15. Superhydrophobic surfaces of electrospun block copolymer fibers with low content of fluorosilicones

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Xiaoping [Key Laboratory of Advanced Textile Materials and Manufacturing Technology, Ministry of Education, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Engineering Research Center for Eco-Dyeing and Finishing of Textiles, Ministry of Education, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Yi, Lingmin, E-mail: lmyi@zstu.edu.cn [Key Laboratory of Advanced Textile Materials and Manufacturing Technology, Ministry of Education, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Engineering Research Center for Eco-Dyeing and Finishing of Textiles, Ministry of Education, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Department of Chemical Engineering and Materials Science, Stevens Institute of Technology, Hoboken, NJ 07030 (United States); Meng, Xiaomei; Xu, Kai [Key Laboratory of Advanced Textile Materials and Manufacturing Technology, Ministry of Education, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Engineering Research Center for Eco-Dyeing and Finishing of Textiles, Ministry of Education, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Jiang, Tengteng; Lai, Dongzhi [Key Laboratory of Advanced Textile Materials and Manufacturing Technology, Ministry of Education, Zhejiang Sci-Tech University, Hangzhou 310018 (China)

    2014-07-01

    A series of well-defined poly[methyl(3,3,3-trifluoropropyl)siloxane]-b-poly(methyl methacrylate) (PMTFPS-b-PMMA) diblock copolymers with low content of PMTFPS were synthesized by atom transfer radical polymerization (ATRP) of MMA from PMTFPS macroinitiators (PMTFPS-Br). The polymerization result reveals that the ATRP of MMA from PMTFPS-Br is fist-order with respect to MMA under different polymerization conditions, demonstrating a typical characteristic of living polymerization. The results also show that PMTFPS-b-PMMA diblock copolymers can exhibit a total surface tension (γ{sub S}) varying from 25.28 mN/m to 21.87 mN/m with the change of PMTFPS contents from 2.6 wt% to 22.2 wt%. Moreover, the water contact angles of electrospun PMTFPS-b-PMMA surfaces could be higher than 150° with water roll-off angles less than 10°, which denotes a superhydrophobic property. However, the electronspinning conditions, especially the concentration of spinning solution, would have important effect on the surface morphology, surface composition and wetting behavior of electrospun films. It was found that bead-free fibers with uniform diameter as well as good superhydrophobic property could be prepared on condition that the polymer concentration of spinning solution was as high as 32 wt% in the mixed solvent of DMF and THF.

  16. Visualization of the distribution of surface-active block copolymers in PDMS-based coatings

    DEFF Research Database (Denmark)

    Noguer, A. Camós; Latipov, R.; Madsen, F. B.

    2018-01-01

    and added to a PDMS coating for visualization purposes. The surface-activity and biofouling resistance of the synthesized copolymer was confirmed by water contact angle measurements and seawater immersion experiments. Confocal laser scanning microscopy (CLSM) images showed that the triblock copolymer...

  17. Carboranedithiols: Building Blocks for Self-Assembled Monolayers on Copper Surfaces

    Czech Academy of Sciences Publication Activity Database

    Baše, Tomáš; Bastl, Zdeněk; Havránek, Vladimír; Macháček, Jan; Langecker, Jens; Malina, Václav

    2012-01-01

    Roč. 28, č. 34 (2012), s. 12518-12526 ISSN 0743-7463 R&D Projects: GA ČR GAP205/10/0348; GA AV ČR KAN100400702 Institutional support: RVO:61388980 ; RVO:61388955 ; RVO:61389005 ; RVO:67985882 Keywords : copper surfaces * carboranethiols * cluster * chemisorption * self-assembled monolayer Subject RIV: CA - Inorganic Chemistry; CF - Physical ; Theoretical Chemistry (UFCH-W) Impact factor: 4.187, year: 2012

  18. Surface modification of polyhedral oligomeric silsesquioxane block copolymer films by 157 nm laser light

    Science.gov (United States)

    Sarantopoulou, Evangelia; Kollia, Zoe; Cefalas, Alkiviadis Constantinos; Siokou, Ageliki Elina; Argitis, Panagiotis; Bellas, Vassilios; Kobe, Spomenka

    2009-06-01

    Thin films of ethyl polyhedral oligomeric silsesquioxane (ethyl-POSS) containing polymers at different compositions were chemically modified using laser irradiation at 157 nm. The irradiation caused photodissociation of C-O and C-H bonds followed by the formation of new chemical bonds. The content of Si-O and C-O bonds increased, as did the surface hardness. Vacuum ultraviolet (VUV) absorption, mass spectrometry, x-ray photoelectron spectroscopy, and atomic force microscopy imaging and indentation were used to evaluate the effects of the 157 nm irradiation. The chemical modification was restricted to a thin surface layer. The layer depth was determined by the penetration depth of the 157 nm VUV photons inside the thin copolymer layer. With prolonged VUV irradiation, the absorbance of the polymers increased, eventually becoming saturated. The chemical changes were accompanied by surface hardening, as evidenced by the increase in the Young's modulus from 4 to 24 GPa due to glassification of the irradiated parts. The chemically modified layer acts as a shield against photodissociation and degradation of the deeper portion of the POSS polymer by VUV radiation. Applications include the protection of solar cells on low orbit satellites from solar VUV photons.

  19. Expression of variant surface antigens by Plasmodium falciparum parasites in the peripheral blood of clinically immune pregnant women indicates ongoing placental infection

    DEFF Research Database (Denmark)

    Ofori, Michael F; Staalsoe, Trine; Bam, Victoria

    2003-01-01

    Placenta-sequestered Plasmodium falciparum parasites that cause pregnancy-associated malaria (PAM) in otherwise clinically immune women express distinct variant surface antigens (VSA(PAM)) not expressed by parasites in nonpregnant individuals. We report here that parasites from the peripheral blood...... of clinically immune pregnant women also express VSA(PAM), making them a convenient source of VSA(PAM) expressors for PAM vaccine research....

  20. Immune selection and within-host competition can structure the repertoire of variant surface antigens in Plasmodium falciparum -a mathematical model

    DEFF Research Database (Denmark)

    van Noort, Sander P; Nunes, Marta C; Weedall, Gareth D

    2010-01-01

    -studied VSA family is erythrocyte membrane protein 1 (PfEMP1). Each parasite genome encodes about 60 PfEMP1 variants, which are important virulence factors and major targets of host antibody responses. Transcriptional switching is the basis of clonal PfEMP1 variation and immune evasion. A relatively conserved......BACKGROUND: The evolutionary mechanisms structuring the expression pattern of variant surface antigen (VSA) families that allow pathogens to evade immune responses and establish chronic and repeated infections pose major challenges to theoretical research. In Plasmodium falciparum, the best...... evidence regarding VSAs, in particular PfEMP1, to formulate a mathematical model of the evolutionary mechanisms shaping VSA organization and expression patterns. The model integrates the transmission dynamics between hosts and the competitive interactions within hosts, based on the hypothesis that the VSAs...

  1. Surface tectonics of nanoporous networks of melamine-capped molecular building blocks formed through interface Schiff-base reactions.

    Science.gov (United States)

    Liu, Xuan-He; Wang, Dong; Wan, Li-Jun

    2013-10-01

    Control over the assembly of molecules on a surface is of great importance for the fabrication of molecule-based miniature devices. Melamine (MA) and molecules with terminal MA units are promising candidates for supramolecular interfacial packing patterning, owing to their multiple hydrogen-bonding sites. Herein, we report the formation of self-assembled structures of MA-capped molecules through a simple on-surface synthetic route. MA terminal groups were successfully fabricated onto rigid molecular cores with 2-fold and 3-fold symmetry through interfacial Schiff-base reactions between MA and aldehyde groups. Sub-molecular scanning tunneling microscopy (STM) imaging of the resultant adlayer revealed the formation of nanoporous networks. Detailed structural analysis indicated that strong hydrogen-bonding interactions between the MA groups persistently drove the formation of nanoporous networks. Herein, we demonstrate that functional groups with strong hydrogen-bond-formation ability are promising building blocks for the guided assembly of nanoporous networks and other hierarchical 2D assemblies. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Novel Plasmodium falciparum malaria vaccines: evidence-based searching for variant surface antigens as candidates for vaccination against pregnancy-associated malaria

    DEFF Research Database (Denmark)

    Staalsoe, Trine; Jensen, Anja T R; Theander, Thor G

    2002-01-01

    Malaria vaccine development has traditionally concentrated on careful molecular, biochemical, and immunological characterisation of candidate antigens. In contrast, evidence of the importance of identified antigens in immunity to human infection and disease has generally been limited......) in particular, to provide robust evidence of a causal link between the two in order to allow efficient and evidence-based identification of candidate antigens for malaria vaccine development....... to statistically significant co-variation with protection rather than on demonstration of causal relationships. We have studied the relationship between variant surface antigen-specific antibodies and clinical protection from Plasmodium falciparum malaria in general, and from pregnancy-associated malaria (PAM...

  3. Breaking tolerance in hepatitis B surface antigen (HBsAg) transgenic mice by vaccination with cross-reactive, natural HBsAg variants

    DEFF Research Database (Denmark)

    Schirmbeck, Reinhold; Dikopoulos, Nektarios; Kwissa, Marcin

    2003-01-01

    Processing exogenous hepatitis B surface antigen (HBsAg) of the hepatitis B virus (HBV) generates the K(b)-binding S(208-215) epitope 1; processing endogenous HBsAg generates the K(b)-binding S(190-197) epitope 2. Cross-reactive CD8(+) T cell responses were primed to epitope 1 but not epitope 2...... HBs-tg mice showed reduced antigenemia. Hence, vaccination with natural HBsAg variants from different HBV sero/genotypes can prime cross-reactive, specific CD8(+) T cell immunity that breaks tolerance to HBsAg....

  4. Insecticide-treated bed nets reduce plasma antibody levels and limit the repertoire of antibodies to Plasmodium falciparum variant surface antigens

    DEFF Research Database (Denmark)

    Askjaer, N; Maxwell, C; Chambo, W

    2001-01-01

    The use of insecticide-treated bed nets (ITN) has been documented to reduce malaria morbidity and mortality in areas with endemic malaria, but concerns have been raised that ITN usage could affect the acquisition of malaria immunity. Several lines of evidence have indicated that antibodies against...... variant surface antigens (VSA) are important in the development of naturally acquired immunity to Plasmodium falciparum malaria and may thus be good indicators of immune status. We have compared the levels of VSA antibodies in plasma from children who have used ITN for 4 years to levels in plasma from...

  5. Swelling-induced morphology reconstruction in block copolymer nanorods: kinetics and impact of surface tension during solvent evaporation.

    Science.gov (United States)

    Wang, Yong; Tong, Ling; Steinhart, Martin

    2011-03-22

    Nanoscopic domain structures of BCP nanorods can be converted into well-defined mesopore systems by swelling the BCP minority component with a selective solvent at temperatures below the bulk glass transition temperature of the nonswelling matrix. The initial stage of this process involves rapid morphology reconstruction of the nonswelling majority domains to accommodate the increased volume of the swelling minority domains caused by rapid solvent uptake. Morphology reconstruction slows down once entropic restoring forces of the swelling chains impede further uptake of swelling agent. Upon evaporation of the swelling agent, mesopores form in place of the swollen domains as the swollen minority blocks undergo entropic relaxation while intermediate nonequilibrium morphologies in the BCP nanorods are fixated by the reconstructed majority component. The surface area of mesopores developing when swollen cylindrical minority domains collapse may be minimized by the growth of Rayleigh instabilities. Depending on swelling temperature, swelling agent, and BCP architecture, BCP nanorods with one or several cylindrical channels undulated or uniform in diameter running along their long axes, linear strings of spherical cavities, and continuous mesopore systems can be obtained.

  6. Modeling malaria infection and immunity against variant surface antigens in Príncipe island, West Africa

    DEFF Research Database (Denmark)

    Bandeiras, Cátia; Trovoada, Maria Jesus; Gonçalves, Lígia A

    2014-01-01

    the impact of reducing exposure to the parasite on the immune repertoire against P. falciparum erythrocyte membrane protein 1 (PfEMP1) variants. The model was parameterized with data from Príncipe Island, West Africa, and applied to simulate two alternative transmission scenarios: one where control measures...... are continued to eventually drive the system to elimination; and another where the effort is interrupted after 6 years of its initiation and the system returns to the initial transmission potential. Population dynamics of parasite prevalence predict that in a few years infection levels return to the pre...

  7. Effects of pregnancy and intensity of Plasmodium falciparum transmission on immunoglobulin G subclass responses to variant surface antigens

    DEFF Research Database (Denmark)

    Megnekou, Rosette; Staalsoe, Trine; Taylor, Diane W

    2005-01-01

    Placenta-sequestering Plasmodium falciparum involved in the pathogenesis of pregnancy-associated malaria (PAM) in otherwise clinically immune women expresses particular variant surface antigens (VSA(PAM)) on the surface of infected erythrocytes that differ from VSA found in parasitized nonpregnant...... individuals (non-PAM type VSA). We studied levels of immunoglobulin G (IgG) and IgG subclasses with specificity for VSA(PAM) and for non-PAM type VSA in pregnant and nonpregnant women from two sites with different endemicities in Cameroon. We found that VSA(PAM)-specific responses depended on the pregnancy...... status, parity, gestational age, and parasite transmission intensity, whereas only the parasite transmission intensity influenced the levels of IgG specific for non-PAM type VSA. For both types of VSA, the responses were dominated by the cytophilic subclass IgG1, followed by IgG3. In pregnant women...

  8. WAIS-IV administration errors: effects of altered response requirements on Symbol Search and violation of standard surface-variety patterns on Block Design.

    Science.gov (United States)

    Ryan, Joseph J; Swopes-Willhite, Nicole; Franklin, Cassi; Kreiner, David S

    2015-01-01

    This study utilized a sample of 50 college students to assess the possibility that responding to the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) Symbol Search subtest items with an "x" instead of a "single slash mark" would affect performance. A second sample of 50 college students was used to assess the impact on WAIS-IV Block Design performance of presenting all the items with only red surfaces facing up. The modified Symbol Search and Block Design administrations yielded mean scaled scores and raw scores that did not differ significantly from mean scores obtained with standard administrations. Findings should not be generalized beyond healthy, well-educated young adults.

  9. A tandem queue with server slow-down and blocking

    NARCIS (Netherlands)

    van Foreest, N.D.; van Ommeren, Jan C.W.; Mandjes, M.R.H.; Scheinhardt, Willem R.W.

    2005-01-01

    We consider two variants of a two-station tandem network with blocking. In both variants the first server ceases to work when the queue length at the second station hits a 'blocking threshold.' In addition, in variant 2 the first server decreases its service rate when the second queue exceeds a

  10. A tandem queue with server slow-down and blocking.

    NARCIS (Netherlands)

    van Foreest, N.; van Ommeren, J.C.; Mandjes, M.R.H.; Scheinhardt, W.

    2005-01-01

    We consider two variants of a two-station tandem network with blocking. In both variants the first server ceases to work when the queue length at the second station hits a 'blocking threshold.' In addition, in variant 2 the first server decreases its service rate when the second queue exceeds a

  11. The surface electrocardiogram predicts risk of heart block during right heart catheterization in patients with preexisting left bundle branch block: implications for the definition of complete left bundle branch block.

    Science.gov (United States)

    Padanilam, Benzy J; Morris, Kent E; Olson, Jeff A; Rippy, Janet S; Walsh, Mary Norine; Subramanian, Natrajan; Vidal, Alex; Prystowsky, Eric N; Steinberg, Leonard A

    2010-07-01

    Patients with left bundle branch block (LBBB) undergoing right heart catheterization can develop complete heart block (CHB) or right bundle branch block (RBBB) in response to right bundle branch (RBB) trauma. We hypothesized that LBBB patients with an initial r wave (>or=1 mm) in lead V1 have intact left to right ventricular septal (VS) activation suggesting persistent conduction over the left bundle branch. Trauma to the RBB should result in RBBB pattern rather than CHB in such patients. Between January 2002 and February 2007, we prospectively evaluated 27 consecutive patients with LBBB developing either CHB or RBBB during right heart catheterization. The prevalence of an r wave >or=1 mm in lead V1 was determined using 118 serial LBBB electrocardiographs (ECGs) from our hospital database. Catheter trauma to the RBB resulted in CHB in 18 patients and RBBB in 9 patients. All 6 patients with >or=1 mm r wave in V1 developed RBBB. Among these 6 patients q wave in lead I, V5, or V6 were present in 3. Four patients (3 in CHB group and 1 in RBBB group) developed spontaneous CHB during a median follow-up of 61 months. V1 q wave >or=1 mm was present in 28% of hospitalized complete LBBB patients. An initial r wave of >or=1 mm in lead V1 suggests intact left to right VS activation and identifies LBBB patients at low risk of CHB during right heart catheterization. These preliminary findings indicate that an initial r wave of >or=1 mm in lead V1, present in approximately 28% of ECGs with classically defined LBBB, may constitute a new exclusion criterion when defining complete LBBB.

  12. Differential induction of immunoglobulin G to Plasmodium falciparum variant surface antigens during the transmission season in Daraweesh, Sudan

    DEFF Research Database (Denmark)

    Nielsen, Morten A; Grevstad, Berit; A-Elgadir, Thoraya M E

    2005-01-01

    BACKGROUND: The acquisition of immunoglobulin (Ig) G to variant surface antigens (VSAs) seems important for the development of protective immunity against malaria. Unlike VSAs expressed by parasite isolates associated with uncomplicated malaria, VSAs expressed by parasite isolates associated...... with severe malaria (VSA(SM)) are frequently recognized by IgG. METHODS: We analyzed levels of anti-VSA IgG in 57 individuals in Daraweesh, Sudan, before and after the transmission season. IgG responses to 79 Plasmodium falciparum isolates from children with defined malaria syndromes and exposed to high......G. CONCLUSIONS: Anti-VSA IgG levels decrease in the absence of infection, and an episode of clinical malaria induces IgG against a range of VSAs, particularly VSAs(SM)....

  13. Human T-cell recognition of synthetic peptides representing conserved and variant sequences from the merozoite surface protein 2 of Plasmodium falciparum

    DEFF Research Database (Denmark)

    Theander, T G; Hviid, L; Dodoo, D

    1997-01-01

    Merozoite surface protein 2 (MSP2) is a malaria vaccine candidate currently undergoing clinical trials. We analyzed the peripheral blood mononuclear cell (PBMC) response to synthetic peptides corresponding to conserved and variant regions of the FCQ-27 allelic form of MSP2 in Ghanaian individuals...... from an area of hyperendemic malaria transmission and in Danes without exposure to malaria. PBMC from 20-39% of Ghanaians responded to each of the peptides by proliferation and 29-36% had PBMC which produced interferon-gamma (IFN-gamma) in response to peptide stimulation. In Danes......, there was no proliferation to two of the peptides and only PBMC from 5% of the individuals proliferated to the other three peptides. IFN-gamma production was not detected to any peptide. In both Danes and Ghanaians in only a few instances was IL-4 detected in the PBMC cultures. Overall PBMC from 79% of the Ghanaians...

  14. In Vitro Variant Surface Antigen Expression in Plasmodium falciparum Parasites from a Semi-Immune Individual Is Not Correlated with Var Gene Transcription

    Science.gov (United States)

    Tschan, Serena; Flötenmeyer, Matthias; Koch, Iris; Berger, Jürgen; Kremsner, Peter; Frank, Matthias

    2016-01-01

    Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) is considered to be the main variant surface antigen (VSA) of Plasmodium falciparum and is mainly localized on electron-dense knobs in the membrane of the infected erythrocyte. Switches in PfEMP1 expression provide the basis for antigenic variation and are thought to be critical for parasite persistence during chronic infections. Recently, strain transcending anti-PfEMP1 immunity has been shown to develop early in life, challenging the role of PfEMP1 in antigenic variation during chronic infections. In this work we investigate how P. falciparum achieves persistence during a chronic asymptomatic infection. The infected individual (MOA) was parasitemic for 42 days and multilocus var gene genotyping showed persistence of the same parasite population throughout the infection. Parasites from the beginning of the infection were adapted to tissue culture and cloned by limiting dilution. Flow cytometry using convalescent serum detected a variable surface recognition signal on isogenic clonal parasites. Quantitative real-time PCR with a field isolate specific var gene primer set showed that the surface recognition signal was not correlated with transcription of individual var genes. Strain transcending anti-PfEMP1 immunity of the convalescent serum was demonstrated with CD36 selected and PfEMP1 knock-down NF54 clones. In contrast, knock-down of PfEMP1 did not have an effect on the antibody recognition signal in MOA clones. Trypsinisation of the membrane surface proteins abolished the surface recognition signal and immune electron microscopy revealed that antibodies from the convalescent serum bound to membrane areas without knobs and with knobs. Together the data indicate that PfEMP1 is not the main variable surface antigen during a chronic infection and suggest a role for trypsin sensitive non-PfEMP1 VSAs for parasite persistence in chronic infections. PMID:27907004

  15. The fabrication of thin films with nanopores and nanogrooves from block copolymer thin films on the neutral surface of self-assembled monolayers

    Science.gov (United States)

    Park, Dae-Ho

    2007-09-01

    A simple and well-ordered fabrication procedure for polymeric thin films with nanopores and nanogrooves is described. By utilizing the neutral surface of self-assembled monolayers (SAMs) of commercially available 3-(p-methoxyphenyl)propyltrichlorosilane (MPTS), the cylindrical microdomains of PMMA of the asymmetric polystyrene-b-poly(methyl methacrylate) (PS-b-PMMA) block copolymer were oriented perpendicular to the surface due to the balanced interfacial interactions of the blocks with the surface. Thin films with perpendicularly oriented lamellae without mixed lamellae could also be fabricated by simply using a binary blend of the same asymmetric PS-b-PMMA diblock copolymer and PMMA homopolymer in the wet-brush regime up to 50% of the total PMMA weight fraction on the same neutral surface. Nanotemplates with arrays of nanopores and nanogrooves were fabricated by selective removal of PMMA domains via ultraviolet (UV) irradiation and sequential washing. SAMs of MPTS on a substrate with aluminium oxide surface were also fabricated and were used to fabricate nanoporous thin film. A thin film of PS-b-PEO with perpendicularly oriented poly(ethylene oxide) (PEO) domains on the SAMs of MPTS is also demonstrated.

  16. The fabrication of thin films with nanopores and nanogrooves from block copolymer thin films on the neutral surface of self-assembled monolayers

    Energy Technology Data Exchange (ETDEWEB)

    Park, Dae-Ho [Department of Materials Science and Engineering, Polymer Research Institute, Pohang University of Science and Technology, San 31, Hyoja-Dong, Nam-Gu, Pohang 790-784 (Korea, Republic of)

    2007-09-05

    A simple and well-ordered fabrication procedure for polymeric thin films with nanopores and nanogrooves is described. By utilizing the neutral surface of self-assembled monolayers (SAMs) of commercially available 3-(p-methoxyphenyl)propyltrichlorosilane (MPTS), the cylindrical microdomains of PMMA of the asymmetric polystyrene-b-poly(methyl methacrylate) (PS-b-PMMA) block copolymer were oriented perpendicular to the surface due to the balanced interfacial interactions of the blocks with the surface. Thin films with perpendicularly oriented lamellae without mixed lamellae could also be fabricated by simply using a binary blend of the same asymmetric PS-b-PMMA diblock copolymer and PMMA homopolymer in the wet-brush regime up to 50% of the total PMMA weight fraction on the same neutral surface. Nanotemplates with arrays of nanopores and nanogrooves were fabricated by selective removal of PMMA domains via ultraviolet (UV) irradiation and sequential washing. SAMs of MPTS on a substrate with aluminium oxide surface were also fabricated and were used to fabricate nanoporous thin film. A thin film of PS-b-PEO with perpendicularly oriented poly(ethylene oxide) (PEO) domains on the SAMs of MPTS is also demonstrated.

  17. E-Block: A Tangible Programming Tool with Graphical Blocks

    OpenAIRE

    Danli Wang; Yang Zhang; Shengyong Chen

    2013-01-01

    This paper designs a tangible programming tool, E-Block, for children aged 5 to 9 to experience the preliminary understanding of programming by building blocks. With embedded artificial intelligence, the tool defines the programming blocks with the sensors as the input and enables children to write programs to complete the tasks in the computer. The symbol on the programming block's surface is used to help children understanding the function of each block. The sequence information is transfer...

  18. Nanotextured Si surfaces derived from block-copolymer self-assembly with superhydrophobic, superhydrophilic, or superamphiphobic properties

    DEFF Research Database (Denmark)

    Telecka, Agnieszka; Li, Tao; Ndoni, Sokol

    2018-01-01

    , or high aspect ratio nano-hoodoo features (overhang profile structures) with a diameter below 100 nm. The surfaces are finally functionalized with either hydrophobic surface chemistry by self-assembly from the precursor perfluorodecyltrichlorosilane (FDTS), or hydrophilic surface chemistry obtained...

  19. Non-surface activity and micellization behavior of cationic amphiphilic block copolymer synthesized by reversible addition-fragmentation chain transfer process.

    Science.gov (United States)

    Ghosh, Arjun; Yusa, Shin-ichi; Matsuoka, Hideki; Saruwatari, Yoshiyuki

    2011-08-02

    Cationic amphiphilic diblock copolymers of poly(n-butylacrylate)-b-poly(3-(methacryloylamino)propyl)trimethylammonium chloride) (PBA-b-PMAPTAC) with various hydrophobic and hydrophilic chain lengths were synthesized by a reversible addition-fragmentation chain transfer (RAFT) process. Their molecular characteristics such as surface activity/nonactivity were investigated by surface tension measurements and foam formation observation. Their micelle formation behavior and micelle structure were investigated by fluorescence probe technique, static and dynamic light scattering (SLS and DLS), etc., as a function of hydrophilic and hydrophobic chain lengths. The block copolymers were found to be non-surface active because the surface tension of the aqueous solutions did not change with increasing polymer concentration. Critical micelle concentration (cmc) of the polymers could be determined by fluorescence and SLS measurements, which means that these polymers form micelles in bulk solution, although they were non-surface active. Above the cmc, the large blue shift of the emission maximum of N-phenyl-1-naphthylamine (NPN) probe and the low micropolarity value of the pyrene probe in polymer solution indicate the core of the micelle is nonpolar in nature. Also, the high value of the relative intensity of the NPN probe and the fluorescence anisotropy of the 1,6-diphenyl-1,3,5-hexatriene (DPH) probe indicated that the core of the micelle is highly viscous in nature. DLS was used to measure the average hydrodynamic radii and size distribution of the copolymer micelles. The copolymer with the longest PBA block had the poorest water solubility and consequently formed micelles with larger size while having a lower cmc. The "non-surface activity" was confirmed for cationic amphiphilic diblock copolymers in addition to anionic ones studied previously, indicating the universality of non-surface activity nature.

  20. Coronary anatomy characteristics in patients with isolated right bundle branch block versus subjects with normal surface electrocardiogram.

    Science.gov (United States)

    Pakbaz, Marziyeh; Kazemisaeid, Ali; Yaminisharif, Ahmad; Davoodi, Gholamreza; Tokaldany, Masoumeh Lotfi; Hakki, Elham

    2013-03-01

    Isolated right bundle branch block is a common finding in the general population. It may be associated with variations in detailed coronary anatomy characteristics. The aim of this study was to investigate the coronary anatomy in patients with isolated right bundle branch block and to compare that with normal individuals. In this case-control study we investigated the coronary anatomy by reviewing angiographic films in two groups of normal coronary artery patients: patients with right bundle branch block (RBBB) (n = 92) and those with normal electrocardiograms (n = 184). There was no significant difference between the two groups in terms of diminutive left anterior descending artery, dominancy, number of obtuse marginal artery, diagonal, acute marginal artery, the position of the first septal versus diagonal branch, presence of ramus artery, and size of left main artery. The number of septal branches was higher in the case group (p-value right circulatory system was more common in both groups but cases showed more tendency to follow this pattern (p-value = 0.021). The frequency of the normal conus branch was higher in the cases versus controls (p-value = 0.009). Coronary anatomy characteristics are somewhat different in subjects with RBBB compared to normal individuals.

  1. Population Blocks.

    Science.gov (United States)

    Smith, Martin H.

    1992-01-01

    Describes an educational game called "Population Blocks" that is designed to illustrate the concept of exponential growth of the human population and some potential effects of overpopulation. The game material consists of wooden blocks; 18 blocks are painted green (representing land), 7 are painted blue (representing water); and the remaining…

  2. Construction and expression of hepatitis B surface antigen escape variants within the "a" determinant by site directed mutagenesis.

    Science.gov (United States)

    Golsaz Shirazi, Forough; Amiri, Mohammad Mehdi; Mohammadi, Hamed; Bayat, Ali Ahmad; Roohi, Azam; Khoshnoodi, Jalal; Zarnani, Amir Hassan; Jeddi-Tehrani, Mahmood; Kardar, Gholam Ali; Shokri, Fazel

    2013-09-01

    The antibody response to hepatitis B surface antigen (HBsAg) controls hepatitis B virus infection. The "a" determinant of HBsAg is the most important target for protective antibody response, diagnosis and immunoprophylaxis. Mutations in this area may induce immune escape mutants and affect the performance of HBsAg assays. To construct clinically relevant recombinant mutant forms of HBsAg and assessment of their reactivity with anti-HBs monoclonal antibodies (MAbs). Wild type (wt) and mutant (mt) HBsAg genes were constructed by site directed mutagenesis and SEOing PCR. The amplified genes were inserted into pCMV6-neo plasmid and transfected in CHO cell line. The expression of wt- and mtHBsAg was assessed by commercial ELISA assays and stable cells were established and cloned by limiting dilution. The recombinant mutants were further characterized using a panel of anti-HBs monoclonal antibodies (MAbs) and the pattern of their reactivity was assessed by ELISA. Ten HBsAg mutants having single mutation within the "a" determinant including P120E, T123N, Q129H, M133L, K141E, P142S, D144A, G145R, N146S and C147S together with a wt form were successfully constructed and expressed in CHO cells. Reactivity of anti-HBs MAbs with mtHBsAgs displayed different patterns. The effect of mutations on antibody binding differed depending on the amino acid involved and its location within the ''a'' determinant. Mutation at amino acids 123 and 145 resulted in either complete loss or significant reduction of binding to all anti-HBs MAbs. Our panel of mtHBsAgs is a valuable tool for assessment of the antibody response to HBV escape mutants and may have substantial implications in HBV immunological diagnostics.

  3. Rapid and Highly Sensitive Detection of Variant Creutzfeldt-Jakob Disease Abnormal Prion Protein on Steel Surfaces by Protein Misfolding Cyclic Amplification: Application to Prion Decontamination Studies.

    Directory of Open Access Journals (Sweden)

    Maxime Belondrade

    Full Text Available The prevalence of variant Creutzfeldt-Jakob disease (vCJD in the population remains uncertain, although it has been estimated that 1 in 2000 people in the United Kingdom are positive for abnormal prion protein (PrPTSE by a recent survey of archived appendix tissues. The prominent lymphotropism of vCJD prions raises the possibility that some surgical procedures may be at risk of iatrogenic vCJD transmission in healthcare facilities. It is therefore vital that decontamination procedures applied to medical devices before their reprocessing are thoroughly validated. A current limitation is the lack of a rapid model permissive to human prions. Here, we developed a prion detection assay based on protein misfolding cyclic amplification (PMCA technology combined with stainless-steel wire surfaces as carriers of prions (Surf-PMCA. This assay allowed the specific detection of minute quantities (10-8 brain dilution of either human vCJD or ovine scrapie PrPTSE adsorbed onto a single steel wire, within a two week timeframe. Using Surf-PMCA we evaluated the performance of several reference and commercially available prion-specific decontamination procedures. Surprisingly, we found the efficiency of several marketed reagents to remove human vCJD PrPTSE was lower than expected. Overall, our results demonstrate that Surf-PMCA can be used as a rapid and ultrasensitive assay for the detection of human vCJD PrPTSE adsorbed onto a metallic surface, therefore facilitating the development and validation of decontamination procedures against human prions.

  4. Rapid and Highly Sensitive Detection of Variant Creutzfeldt - Jakob Disease Abnormal Prion Protein on Steel Surfaces by Protein Misfolding Cyclic Amplification: Application to Prion Decontamination Studies

    Science.gov (United States)

    Belondrade, Maxime; Nicot, Simon; Béringue, Vincent; Coste, Joliette; Lehmann, Sylvain; Bougard, Daisy

    2016-01-01

    The prevalence of variant Creutzfeldt-Jakob disease (vCJD) in the population remains uncertain, although it has been estimated that 1 in 2000 people in the United Kingdom are positive for abnormal prion protein (PrPTSE) by a recent survey of archived appendix tissues. The prominent lymphotropism of vCJD prions raises the possibility that some surgical procedures may be at risk of iatrogenic vCJD transmission in healthcare facilities. It is therefore vital that decontamination procedures applied to medical devices before their reprocessing are thoroughly validated. A current limitation is the lack of a rapid model permissive to human prions. Here, we developed a prion detection assay based on protein misfolding cyclic amplification (PMCA) technology combined with stainless-steel wire surfaces as carriers of prions (Surf-PMCA). This assay allowed the specific detection of minute quantities (10−8 brain dilution) of either human vCJD or ovine scrapie PrPTSE adsorbed onto a single steel wire, within a two week timeframe. Using Surf-PMCA we evaluated the performance of several reference and commercially available prion-specific decontamination procedures. Surprisingly, we found the efficiency of several marketed reagents to remove human vCJD PrPTSE was lower than expected. Overall, our results demonstrate that Surf-PMCA can be used as a rapid and ultrasensitive assay for the detection of human vCJD PrPTSE adsorbed onto a metallic surface, therefore facilitating the development and validation of decontamination procedures against human prions. PMID:26800081

  5. Rapid and Highly Sensitive Detection of Variant Creutzfeldt-Jakob Disease Abnormal Prion Protein on Steel Surfaces by Protein Misfolding Cyclic Amplification: Application to Prion Decontamination Studies.

    Science.gov (United States)

    Belondrade, Maxime; Nicot, Simon; Béringue, Vincent; Coste, Joliette; Lehmann, Sylvain; Bougard, Daisy

    2016-01-01

    The prevalence of variant Creutzfeldt-Jakob disease (vCJD) in the population remains uncertain, although it has been estimated that 1 in 2000 people in the United Kingdom are positive for abnormal prion protein (PrPTSE) by a recent survey of archived appendix tissues. The prominent lymphotropism of vCJD prions raises the possibility that some surgical procedures may be at risk of iatrogenic vCJD transmission in healthcare facilities. It is therefore vital that decontamination procedures applied to medical devices before their reprocessing are thoroughly validated. A current limitation is the lack of a rapid model permissive to human prions. Here, we developed a prion detection assay based on protein misfolding cyclic amplification (PMCA) technology combined with stainless-steel wire surfaces as carriers of prions (Surf-PMCA). This assay allowed the specific detection of minute quantities (10-8 brain dilution) of either human vCJD or ovine scrapie PrPTSE adsorbed onto a single steel wire, within a two week timeframe. Using Surf-PMCA we evaluated the performance of several reference and commercially available prion-specific decontamination procedures. Surprisingly, we found the efficiency of several marketed reagents to remove human vCJD PrPTSE was lower than expected. Overall, our results demonstrate that Surf-PMCA can be used as a rapid and ultrasensitive assay for the detection of human vCJD PrPTSE adsorbed onto a metallic surface, therefore facilitating the development and validation of decontamination procedures against human prions.

  6. Preparation and Structural Studies on Hybrid Core-Shell Nanoparticles Consisting of Silica Core and Conjugated Block Copolymer Shell Prepared by Surface-Initiated Polymerization

    Science.gov (United States)

    Chatterjee, Sourav; Karam, Tony; Rosu, Cornelia; Li, Xin; Do, Changwoo; Youm, Sang Gil; Haber, Louis; Russo, Paul; Nesterov, Evgueni

    Controlled Kumada catalyst-transfer polymerization occurring by chain-growth mechanism was developed for the synthesis of conjugated polymers and block copolymers from the surface of inorganic substrates such as silica nanoparticles. Although synthesis of conjugated polymers via Kumada polymerization became an established method for solution polymerization, carrying out the same reaction in heterogeneous conditions to form monodisperse polymer chains still remains a challenge. We developed and described a simple and efficient approach to the preparation of surface-immobilized layer of catalytic Ni(II) initiator, and demonstrated using it to prepare polymers and block copolymers on silica nanoparticle. The structure of the resulting hybrid nanostructures was thoroughly studied using small-angle neutron and X-ray scattering, thermal analysis, and optical spectroscopy. The photoexcitation energy transfer processes in the conjugated polymer shell were studied via steady-state and time resolved transient absorption spectroscopy. This study uncovered important details of the energy transfer, which will be discussed in this presentation.

  7. Peptide surface modification of P(HEMA-co-MMA)-b-PIB-b-P(HEMA-co-MMA) block copolymers.

    Science.gov (United States)

    Ojha, Umaprasana; Feng, Dingsong; Chandekar, Amol; Whitten, James E; Faust, Rudolf

    2009-06-02

    Peptide surface modification of poly[(methyl methacrylate-co-hydroxyethyl methacrylate)-b-isobutylene-b-(methyl methacrylate-co-hydroxyethyl methacrylate)] P(MMA-co-HEMA)-b-PIB-b-P(MMA-co-HEMA) triblock copolymers with different HEMA/MMA ratios has been accomplished using an efficient synthetic procedure. The triblock copolymers were reacted with 4-fluorobenzenesulfonyl chloride (fosyl chloride) in pyridine to obtain the activated polymers [poly{(methyl methacrylate-co-fosyloxyethyl methacrylate)-b-isobutylene-b-(methyl methacrylate-co-fosyloxyethyl methacrylate)}] P(MMA-co-FEMA)-b-PIB-b-P(MMA-co-FEMA), with an activating efficiency of 80-90%. The resulting polymers were soluble in chloroform, and their solutions were used to coat thin uniform films with a predetermined thickness on smooth steel surfaces. The presence of reactive activating groups on the film surface was confirmed by X-ray photoelectron spectroscopy (XPS), dye labeling, and confocal laser scanning microscopic studies. Activation of the triblock copolymer films was also achieved under heterogeneous conditions in polar (acetonitrile) and nonpolar (hexanes) media. The extent of activation was controlled by varying the dipping time and polarity of the medium. Peptide attachment was accomplished by immersing the coated steel strips into aqueous buffer solution of Gly-Gly or GYIGSR. XPS and solubility studies revealed successful attachment of peptides to the polymer surface. Virtually all remaining activating groups were successfully replaced in the subsequent step by a treatment with Tris(hydroxymethyl)amino methane in a buffered methanol/water mixture.

  8. Electromechanical properties of 1D ZnO nanostructures: nanopiezotronics building blocks, surface and size-scale effects.

    Science.gov (United States)

    Momeni, Kasra; Attariani, Hamed

    2014-03-14

    One-dimensional (1D) zinc oxide nanostructures are the main components of nanogenerators and central to the emerging field of nanopiezotronics. Understanding the underlying physics and quantifying the electromechanical properties of these structures, the topic of this research study, play a major role in designing next-generation nanoelectromechanical devices. Here, atomistic simulations are utilized to study surface and size-scale effects on the electromechanical response of 1D ZnO nanostructures. It is shown that the mechanical and piezoelectric properties of these structures are controlled by their size, cross-sectional geometry, and loading configuration. The study reveals enhancement of the piezoelectric and elastic modulus of ZnO nanowires (NW) with diameter d > 1 nm, followed by a sudden drop for d macron]1[combining macron]0) and (011[combining macron]0) planes in NBs. Transition from a surface-reconstructed dominant to a surface-relaxed dominant region is demonstrated for lateral dimensions <1 nm. New phase-transformation (PT) kinetics from piezoelectric wurtzite to nonpiezoelectric body-centered tetragonal (WZ → BCT) and graphite-like phase (WZ → HX) structures occurs in ZnO NWs loaded up to large strains of ∼10%.

  9. Right Bundle Branch Block-Like Pattern During Ventricular Pacing: A Surface Electrocardiographic Mapping Technique to Locate the Ventricular Lead.

    Science.gov (United States)

    Almehairi, Mohammed; Enriquez, Andres; Redfearn, Damian; Michael, Kevin; Abdollah, Hoshiar; Alfagih, Ahmed; Nolan, Robert; Baranchuk, Adrian; Simpson, Christopher S

    2015-08-01

    In patients with paced rhythm, a right bundle branch block (RBBB)-like pattern may suggest inadvertent left ventricular (LV) lead placement. However, in most cases, the lead is indeed in the right ventricle as intended. We performed a retrospective analysis of postimplantation electrocardiograms (ECGs) for the period 2000-2013 to determine the prevalence of a RBBB-like pattern. A 12-lead ECG was recorded in the standard position and with displacement of leads V1-V2 to the fifth and sixth intercostal spaces (ICSs), assessing the ability of this manoeuvre to unmask a concealed LBBB-like pattern. Patients with true LV pacing, both endocardial and epicardial, were used as controls (n = 10). A total of 943 patients were analyzed. The prevalence of RBBB-like pattern was 8.1% (n = 77), and 26 patients were included in the study. Displacement of leads V1-V2 to the fifth ICS resulted in transition to a LBBB-like pattern with a QS wave in V1 in 14 of 26 patients (sensitivity, 53%; specificity, 100%), whereas displacement to the sixth ICS resulted in a QS pattern in all patients (sensitivity and specificity, 100%). In all patients in the control group, the ECG depicted a RBBB configuration with leads V1-V2 in the standard position, as well as at the fifth and sixth ICSs. In patients with paced rhythm and a RBBB-like pattern on the 12-lead ECG, displacement of leads V1-V2 to the sixth ICS accurately identifies the presence of true right ventricular pacing. Copyright © 2015 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  10. The microRNAs in an ancient protist repress the variant-specific surface protein expression by targeting the entire coding sequence.

    Directory of Open Access Journals (Sweden)

    Ashesh A Saraiya

    2014-02-01

    Full Text Available microRNAs (miRNA have been detected in the deeply branched protist, Giardia lamblia, and shown to repress expression of the family of variant-specific surface proteins (VSPs, only one of which is expressed in Giardia trophozoite at a given time. Three next-generation sequencing libraries of Giardia Argonaute-associated small RNAs were constructed and analyzed. Analysis of the libraries identified a total of 99 new putative miRNAs with a size primarily in the 26 nt range similar to the size previously predicted by the Giardia Dicer crystal structure and identified by our own studies. Bioinformatic analysis identified multiple putative miRNA target sites in the mRNAs of all 73 VSPs. The effect of miRNA target sites within a defined 3'-region were tested on two vsp mRNAs. All the miRNAs showed partial repression of the corresponding vsp expression and were additive when the targeting sites were separately located. But the combined repression still falls short of 100%. Two other relatively short vsp mRNAs with 15 and 11 putative miRNA target sites identified throughout their ORFs were tested with their corresponding miRNAs. The results indicate that; (1 near 100% repression of vsp mRNA expression can be achieved through the combined action of multiple miRNAs on target sites located throughout the ORF; (2 the miRNA machinery could be instrumental in repressing the expression of vsp genes in Giardia; (3 this is the first time that all the miRNA target sites in the entire ORF of a mRNA have been tested and shown to be functional.

  11. Antibodies against amino acids 1-15 of tumor necrosis factor block its binding to cell-surface receptor.

    OpenAIRE

    Socher, S H; Riemen, M W; Martinez, D; Friedman, A; Tai, J; Quintero, J C; Garsky, V; Oliff, A

    1987-01-01

    Human tumor necrosis factor (hTNF) mediates a variety of biologic activities, which are dependent on the attachment of hTNF to cell-surface receptors. To identify regions of the hTNF protein involved in binding hTNF to its receptor, we prepared five synthetic peptides [hTNF-(1-15), hTNF-(1-31), hTNF-(65-79), hTNF-(98-111), and hTNF-(124-141)] and two hydroxylamine cleavage fragments [hTNF-(1-39) and hTNF-(40-157)] of hTNF. The hTNF-synthetic peptides and hTNF fragments were tested in hTNF rec...

  12. Genetic Diversity of Plasmodium falciparum Merozoite Surface Protein-1 Block 2 in Sites of Contrasting Altitudes and Malaria Endemicities in the Mount Cameroon Region

    Science.gov (United States)

    Wanji, Samuel; Kengne-Ouafo, Arnaud J.; Joan Eyong, Ebanga E.; Kimbi, Helen K.; Tendongfor, Nicholas; Ndamukong-Nyanga, Judith L.; Nana-Djeunga, Hugues C.; Bourguinat, Catherine; Sofeu-Feugaing, David D.; Charvet, Claude L.

    2012-01-01

    The present study analyzed the relationship between the genetic diversity of Plasmodium falciparum and parasitologic/entomologic indices in the Mount Cameroon region by using merozoite surface protein 1 as a genetic marker. Blood samples were collected from asymptomatic children from three altitude zones (high, intermediate, and low). Parasitologic and entomologic indices were determined by microscopy and landing catch mosquito collection/circumsporozoite protein–enzyme-linked immunosorbent assay, respectively. A total of 142 randomly selected P. falciparum-positive blood samples were genotyped by using a nested polymerase chain reaction–based technique. K-1 polymerase chain reaction products were also sequenced. As opposed to high altitude, the highest malaria prevalence (70.65%) and entomologic inoculation rate (2.43 infective/bites/night) were recorded at a low altitude site. Seven (18.91%), 22 (36.66%), and 19 (42.22%) samples from high, intermediate, and low altitudes, respectively, contained multiclonal infections. A new K-1 polymorphism was identified. This study shows a positive non-linear association between low/intermediate altitude (high malaria transmission) and an increase in P. falciparum merozoite surface protein 1 block 2 polymorphisms. PMID:22556072

  13. Surface modification of paclitaxel-loaded tri-block copolymer PLGA- b-PEG- b-PLGA nanoparticles with protamine for liver cancer therapy

    Science.gov (United States)

    Gao, Nansha; Chen, Zhihong; Xiao, Xiaojun; Ruan, Changshun; Mei, Lin; Liu, Zhigang; Zeng, Xiaowei

    2015-08-01

    In order to enhance the therapeutic effect of chemotherapy on liver cancer, a biodegradable formulation of protamine-modified paclitaxel-loaded poly(lactide- co-glycolide)- b-poly(ethylene glycol)- b-poly(lactide- co-glycolide) (PLGA- b-PEG- b-PLGA) nanoparticles (PTX-loaded/protamine NPs) was prepared. Tri-block copolymer PLGA- b-PEG- b-PLGA was synthesized by ring-opening polymerization and characterized by 1H NMR spectroscopy and gel permeation chromatography. PTX-loaded and PTX-loaded/protamine NPs were characterized in terms of size, size distribution, zeta potential, surface morphology, drug encapsulation efficiency, and drug release. Confocal laser scanning microscopy showed that coumarin 6-loaded/protamine NPs were internalized by hepatocellular carcinoma cell line HepG2. The cellular uptake efficiency of NPs was obviously elevated after protamine modification. With commercial formulation Taxol® as the reference, HepG2 cells were also used to study the cytotoxicity of the NPs. PTX-loaded/protamine NPs exhibited significantly higher cytotoxicity than PTX-loaded NPs and Taxol® did. All the results suggested that surface modification of PTX-loaded PLGA- b-PEG- b-PLGA NPs with protamine boosted the therapeutic efficacy on liver cancer.

  14. Surface modification of paclitaxel-loaded tri-block copolymer PLGA-b-PEG-b-PLGA nanoparticles with protamine for liver cancer therapy

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Nansha [Chinese Academy of Science, Research Center for Human Tissues and Organs Degeneration, Shenzhen Institute of Advanced Technology (China); Chen, Zhihong [Guangdong Medical College, Analysis Centre (China); Xiao, Xiaojun [Shenzhen University, Institute of Allergy and Immunology, School of Medicine (China); Ruan, Changshun [Chinese Academy of Science, Research Center for Human Tissues and Organs Degeneration, Shenzhen Institute of Advanced Technology (China); Mei, Lin [Tsinghua University, The Shenzhen Key Lab of Gene and Antibody Therapy, and Division of Life and Health Sciences, Graduate School at Shenzhen (China); Liu, Zhigang, E-mail: lzg@szu.edu.cn [Shenzhen University, Institute of Allergy and Immunology, School of Medicine (China); Zeng, Xiaowei, E-mail: zeng.xiaowei@sz.tsinghua.edu.cn [Tsinghua University, The Shenzhen Key Lab of Gene and Antibody Therapy, and Division of Life and Health Sciences, Graduate School at Shenzhen (China)

    2015-08-15

    In order to enhance the therapeutic effect of chemotherapy on liver cancer, a biodegradable formulation of protamine-modified paclitaxel-loaded poly(lactide-co-glycolide)-b-poly(ethylene glycol)-b-poly(lactide-co-glycolide) (PLGA-b-PEG-b-PLGA) nanoparticles (PTX-loaded/protamine NPs) was prepared. Tri-block copolymer PLGA-b-PEG-b-PLGA was synthesized by ring-opening polymerization and characterized by {sup 1}H NMR spectroscopy and gel permeation chromatography. PTX-loaded and PTX-loaded/protamine NPs were characterized in terms of size, size distribution, zeta potential, surface morphology, drug encapsulation efficiency, and drug release. Confocal laser scanning microscopy showed that coumarin 6-loaded/protamine NPs were internalized by hepatocellular carcinoma cell line HepG2. The cellular uptake efficiency of NPs was obviously elevated after protamine modification. With commercial formulation Taxol{sup ®} as the reference, HepG2 cells were also used to study the cytotoxicity of the NPs. PTX-loaded/protamine NPs exhibited significantly higher cytotoxicity than PTX-loaded NPs and Taxol{sup ®} did. All the results suggested that surface modification of PTX-loaded PLGA-b-PEG-b-PLGA NPs with protamine boosted the therapeutic efficacy on liver cancer.

  15. Differences in human antibody reactivity to Plasmodium falciparum variant surface antigens are dependent on age and malaria transmission intensity in northeastern Tanzania

    DEFF Research Database (Denmark)

    Vestergaard, Lasse S; Lusingu, John P; Nielsen, Morten A

    2008-01-01

    at population level, we conducted an immunoepidemiological study in nearby communities in northeastern Tanzania, situated at different altitudes and therefore exposed to different levels of P. falciparum transmission intensity. Samples of plasma and infected red blood cells (IRBC) were collected from 759...... and functional characteristics of the variant-specific antibody response, which is likely to be important for protection against malaria....

  16. An approach to multiobjective optimization of rotational therapy. II. Pareto optimal surfaces and linear combinations of modulated blocked arcs for a prostate geometry.

    Science.gov (United States)

    Pardo-Montero, Juan; Fenwick, John D

    2010-06-01

    comprising two regions: One where the dose to the target is close to prescription and trade-offs can be made between doses to the organs at risk and (small) changes in target dose, and one where very substantial rectal sparing is achieved at the cost of large target underdosage. Plans computed following the approach using a conformal arc and four blocked arcs generally lie close to the Pareto front, although distances of some plans from high gradient regions of the Pareto front can be greater. Only around 12% of plans lie a relative Euclidean distance of 0.15 or greater from the Pareto front. Using the alternative distance measure of Craft ["Calculating and controlling the error of discrete representations of Pareto surfaces in convex multi-criteria optimization," Phys. Medica (to be published)], around 2/5 of plans lie more than 0.05 from the front. Computation of blocked arcs is quite fast, the algorithms requiring 35%-80% of the running time per iteration needed for conventional inverse plan computation. The geometry-based arc approach to multicriteria optimization of rotational therapy allows solutions to be obtained that lie close to the Pareto front. Both the image-reconstruction type and gradient-descent algorithms produce similar modulated arcs, the latter one perhaps being preferred because it is more easily implementable in standard treatment planning systems. Moderate unblocking provides a good way of dealing with OARs which abut the PTV. Optimization of geometry-based arcs is faster than usual inverse optimization of treatment plans, making this approach more rapid than an inverse-based Pareto front reconstruction.

  17. Block-Localized Density Functional Theory (BLDFT), Diabatic Coupling, and Their Use in Valence Bond Theory for Representing Reactive Potential Energy Surfaces

    Science.gov (United States)

    Cembran, Alessandro; Song, Lingchun; Mo, Yirong; Gao, Jiali

    2010-01-01

    A multistate density functional theory in the framework of the valence bond model is described. The method is based on a block-localized density functional theory (BLDFT) for the construction of valence-bond-like diabatic electronic states and is suitable for the study of electron transfer reactions and for the representation of reactive potential energy surfaces. The method is equivalent to a valence bond theory with the treatment of the localized configurations by using density functional theory (VBDFT). In VBDFT, the electron densities and energies of the valence bond states are determined by BLDFT. A functional estimate of the off-diagonal matrix elements of the VB Hamiltonian is proposed, making use of the overlap integral between Kohn–Sham determinants and the exchange-correlation functional for the ground state substituted with the transition (exchange) density. In addition, we describe an approximate approach, in which the off-diagonal matrix element is computed by wave function theory using block-localized Kohn–Sham orbitals. The key feature is that the electron density of the adiabatic ground state is not directly computed nor used to obtain the ground-state energy; the energy is determined by diagonalization of the multistate valence bond Hamiltonian. This represents a departure from the standard single-determinant Kohn–Sham density functional theory. The multistate VBDFT method is illustrated by the bond dissociation of H2+ and a set of three nucleophilic substitution reactions in the DBH24 database. In the dissociation of H2+, the VBDFT method yields the correct asymptotic behavior as the two protons stretch to infinity, whereas approximate functionals fail badly. For the SN2 nucleophilic substitution reactions, the hybrid functional B3LYP severely underestimates the barrier heights, while the approximate two-state VBDFT method overcomes the self-interaction error, and overestimates the barrier heights. Inclusion of the ionic state in a three

  18. Development of flexible LEO-resistant PI films for space applications using a self-healing mechanism by surface-directed phase separation of block copolymers

    NARCIS (Netherlands)

    Fischer, H.R.; Tempelaars, K.; Kerpershoek, A.M.; Dingemans, T.; Iqbal, M.; Lonkhuyzen, H.; Iwanowsky, B.; Semprimoschnig, C.

    2010-01-01

    Polimide-block-polydimethylsiloxane (PI-b-PDMS) block copolymers have been synthesized from commercially available amino-terminated polysiloxanes with different molecular weights, for use as polymeric materials resistant to the low earth orbit (LEO) space environment. A structural optimization with

  19. Natural acquired inhibitory antibodies to Plasmodium vivax Duffy binding protein (PvDBP-II) equally block erythrocyte binding of homologous and heterologous expressed PvDBP-II on the surface of COS-7 cells.

    Science.gov (United States)

    Valizadeh, Vahideh; Zakeri, Sedigheh; Mehrizi, Akram A; Mirkazemi, Sedigheh; Djadid, Navid D

    2016-02-01

    The binding domain of Plasmodium vivax Duffy binding protein (PvDBP-II) is a promising blood-stage vaccine candidate for vivax malaria. For the development of a successful vivax malaria vaccine based on DBP-II, the antigenic diversity and also naturally occurring functional antibodies to different PvDBP-II variant types in the various populations must be determined. However, similar to other blood-stage antigens, allelic variation within the PvDBP-II is a fundamental challenge for the development of a broadly efficient vaccine. The present study was performed to define whether the polymorphisms in PvDBP-II influence the nature of functional inhibitory activity of naturally acquired or induced anti-DBP-II antibodies in mice. In this investigation, five genetically distinct variants of PvDBP-II were transiently expressed on the COS-7 cell surface. Erythrocyte-binding inhibition assay (EBIA) was performed using human sera infected with corresponding and non-corresponding P. vivax variants as well as by the use of mice sera immunized with different expressed recombinant PvDBP-IIs. EBIA results showed that the inhibitory percentage varied between 50 and 63 % by using sera from infected individuals, and in case of mouse antisera, inhibition was in the range of 76-86 %. Interestingly, no significant difference was detected in red blood cell binding inhibition when different PvDBP-II variants on the COS-7 cell surfaces were incubated with heterologous and homologous sera infected with PvDBP-II variants. This suggests that the detected polymorphisms in all five forms of PvDBP-II may not affect functional activity of anti-DBP-II antibodies. In conclusion, our results revealed that there are functional cross-reactive antibody responses to heterologous PvDBP-II variants that might provide a broader inhibitory response against all, or at least the majority of strains compared to single allele of this protein that should be considered in development of PvDBP-II-based vaccine.

  20. Antibodies to the N-terminal block 2 of Plasmodium falciparum merozoite surface protein 1 are associated with protection against clinical malaria

    DEFF Research Database (Denmark)

    Cavanagh, David R; Dodoo, Daniel; Hviid, Lars

    2004-01-01

    to the block 2 region of MSP-1 were measured in a cohort of 280 children before the beginning of the major malaria transmission season. The cohort was then actively monitored for malaria, clinically and parasitologically, over a period of 17 months. Evidence is presented for an association between antibody...... responses to block 2 and a significantly reduced risk of subsequent clinical malaria. Furthermore, statistical survival analysis provides new information on the duration of the effect over time. The results support a conclusion that the block 2 region of MSP-1 is a target of protective immunity against P....... falciparum and, thus, a promising new candidate for the development of a malaria vaccine....

  1. Ab initio analytical potential energy surface and quasiclassical trajectory study of the O+(4S)+H2(X 1Σg+)→OH+(X 3Σ-)+H(2S) reaction and isotopic variants

    International Nuclear Information System (INIS)

    Martinez, Rodrigo; Millan, Judith; Gonzalez, Miguel

    2004-01-01

    An analytical potential energy surface (PES) representation of the O + ( 4 S)+H 2 (X 1 Σ g + ) system was developed by fitting around 600 CCSD(T)/cc-pVQZ ab initio points. Rate constant calculations for this reaction and its isotopic variants (D 2 and HD) were performed using the quasiclassical trajectory (QCT) method, obtaining a good agreement with experimental data. Calculations conducted to determine the cross section of the title reaction, considering collision energies (E T ) below 0.3 eV, also led to good accord with experiments. This PES appears to be suitable for kinetics and dynamics studies. Moreover, the QCT results show that, although the hypotheses of a widely used capture model are not satisfied, the resulting expression for the cross section can be applied within a suitable E T interval, due to errors cancellation. This could be a general situation regarding the application of this simple model to ion-molecule processes

  2. In vitro selection of Plasmodium falciparum 3D7 for expression of variant surface antigens associated with severe malaria in African children

    DEFF Research Database (Denmark)

    Staalsoe, Trine; Nielsen, Morten A; Vestergaard, Lasse S

    2003-01-01

    P. falciparum-infected red blood cells (IRBC) can adhere to endothelial host receptors through parasite-encoded, clonally variant surface antigens (VSA). The VSA-mediated IRBC adhesion and the acquired VSA-specific antibody response have both been linked to IRBC organ tropism and disease severity....... Parasites isolated from young children with severe malaria (SM) tend to express a limited and conserved set of VSA (VSASM) that are both stronger and more commonly recognized by IgG in the plasma of malaria-exposed individuals than VSA (VSAUM) expressed by parasites causing uncomplicated malaria (UM...... identification of VSASM-encoding genes in 3D7, we report here a method of enforcing expression of VSASM-like antigens in this parasite clone by a novel selection method using plasma from semi-immune children with low VSAUM-specific, but high VSASM-specific, IgG reactivity. In addition to the resulting increase...

  3. Tailored Interfaces for Biosensors and Cell-Surface Interaction Studies via Activation and Derivatization of Polystyrene-block-poly(tert-butyl acrylate) Thin Films

    NARCIS (Netherlands)

    Feng, C.L.; Embrechts, A.; Bredebusch, Ilona; Bouma, Anita; Schnekenburger, Jürgen; Garcia Parajo, M.F.; Domschke, Wolfram; Vancso, Gyula J.; Schönherr, Holger

    2007-01-01

    Thin spin-coated films of polystyrene-block-poly(tert-butyl acrylate) (PS690-b-PtBA1210) on various substrates are introduced as versatile, robust reactive platform for the immobilization of (bio)molecules for the fabrication of tailored biointerfaces. The films are characterized by high stability

  4. An experimental study on advancement of damping performance of foundations in soft ground. Pt.2: Experiment focusing on damping and antivibration performance of side surface of foundation blocks

    International Nuclear Information System (INIS)

    Ishimaru, S.; Shimomura, Y.; Kawamuram, M.; Ikeda, Y.; Hata, I.; Miwa, S.

    2005-01-01

    To aim at progress of damping performance of foundations that will be built at soft ground, we have proposed an improved foundation work of backfilling a damping material into trenches dug along a foundation supported by improved soil medium. This damping material is a mixture of asphalt with crushed stones and rubber chips (MACSRC) and has itself high attenuation and mitigation performance. Not only to comprehend the attenuation ability of the improved foundation work quantitatively and qualitatively but also to verify the effectiveness of this work, we carried out forced vibration tests for two test blocks, which were constructed by a normal construction work and the above improved foundation work. According to the experiment results of the blocks by the normal construction work and by the improved foundation work that were excited by the vibration generator, magnitude of amplitudes of the latter became half than the former. Effectiveness in the attenuation performance of MACSRC was confirmed. When the block by the normal construction work was vibrated, the improved foundation work decreased magnitude of amplitude of the adjacent block than the normal construction work. It is expected that MACSRC would exert mitigation ability against earthquakes or other external and internal forces. (authors)

  5. [Masquerading bundle branch block].

    Science.gov (United States)

    Kukla, Piotr; Baranchuk, Adrian; Jastrzębski, Marek; Bryniarski, Leszek

    2014-01-01

    We here describe a surface 12-lead electrocardiogram (ECG) of a 72-year-old female with a prior history of breast cancer and chemotherapy-induced cardiomyopathy. An echocardiogram revealed left ventricular dysfunction, ejection fraction of 23%, with mild enlarged left ventricle. The 12-lead ECG showed atrial fibrillation with a mean heart rate of about 100 bpm, QRS duration 160 ms, QT interval 400 ms, right bundle branch block (RBBB) and left anterior fascicular block (LAFB). The combination of RBBB features in the precordial leads and LAFB features in the limb leads is known as ''masquerading bundle branch block''. In most cases of RBBB and LAFB, the QRS axis deviation is located between - 80 to -120 degrees. Rarely, when predominant left ventricular forces are present, the QRS axis deviation is near about -90 degrees, turning the pattern into an atypical form. In a situation of RBBB associated with LAFB, the S wave can be absent or very small in lead I. Such a situation is the result of not only purely LAFB but also with left ventricular hypertrophy and/or focal block due to scar (extensive anterior myocardial infarction) or fibrosis (cardiomyopathy). Sometimes, this specific ECG pattern is mistaken for LBBB. RBBB with LAFB may imitate LBBB either in the limb leads (known as 'standard masquerading' - absence of S wave in lead I), or in the precordial leads (called 'precordial masquerading' - absence of S wave in leads V₅ and V₆). Our ECG showed both these types of masquerading bundle branch block - absence of S wave in lead I and in leads V₅ and V₆.

  6. Variants of cellobiohydrolases

    Energy Technology Data Exchange (ETDEWEB)

    Bott, Richard R.; Foukaraki, Maria; Hommes, Ronaldus Wilhelmus; Kaper, Thijs; Kelemen, Bradley R.; Kralj, Slavko; Nikolaev, Igor; Sandgren, Mats; Van Lieshout, Johannes Franciscus Thomas; Van Stigt Thans, Sander

    2018-04-10

    Disclosed are a number of homologs and variants of Hypocrea jecorina Ce17A (formerly Trichoderma reesei cellobiohydrolase I or CBH1), nucleic acids encoding the same and methods for producing the same. The homologs and variant cellulases have the amino acid sequence of a glycosyl hydrolase of family 7A wherein one or more amino acid residues are substituted and/or deleted.

  7. An upper limit for slow-earthquake zones: self-oscillatory behavior through the Hopf bifurcation mechanism from a spring-block model under lubricated surfaces

    Science.gov (United States)

    Castellanos-Rodríguez, Valentina; Campos-Cantón, Eric; Barboza-Gudiño, Rafael; Femat, Ricardo

    2017-08-01

    The complex oscillatory behavior of a spring-block model is analyzed via the Hopf bifurcation mechanism. The mathematical spring-block model includes Dieterich-Ruina's friction law and Stribeck's effect. The existence of self-sustained oscillations in the transition zone - where slow earthquakes are generated within the frictionally unstable region - is determined. An upper limit for this region is proposed as a function of seismic parameters and frictional coefficients which are concerned with presence of fluids in the system. The importance of the characteristic length scale L, the implications of fluids, and the effects of external perturbations in the complex dynamic oscillatory behavior, as well as in the stationary solution, are take into consideration.

  8. The Application of Seismic Attributes and Wheeler Transformations for the Geomorphological Interpretation of Stratigraphic Surfaces: A Case Study of the F3 Block, Dutch Offshore Sector, North Sea

    OpenAIRE

    Mohammad Afifi Ishak; Md. Aminul Islam; Mohamed Ragab Shalaby; Nurul Hasan

    2018-01-01

    This study was carried out in the Pliocene interval of the southern North Sea F3 Block in the Netherlands. This research paper demonstrates how an integrated interpretation of geological information using seismic attributes, sequence stratigraphic interpretation and Wheeler transformation methods allow for the accurate interpretation of the depositional environment of a basin, as well as locating seismic geomorphological features. The methodology adopted here is to generate a 3D dip-steered H...

  9. Surface Self-Assembly and Properties of Monolayers Formed by Reverse Poly(butylene oxide)-poly(ethylene oxide)-poly(butylene oxide) Triblock Copolymers with Lengthy Hydrophilic Blocks

    DEFF Research Database (Denmark)

    Villar-Alvarez, Eva; Freire, Adriana Cambón; Blanco, Mateo

    2017-01-01

    The surface behavior and properties of several reverse poly(butylene oxide)-poly(ethylene oxide)-poly(butylene oxide) block copolymers, BO8EO90BO8, BO12EO227BO12, BO14EO378BO14, BO20EO411BO20, and BO21EO385BO21 at the air/water interface have been analyzed by drop tensiometry, Langmuir film balance......, and atomic force microscopy (AFM). The kinetic adsorption process of block copolymer chains at the air/water interface is a diffusion-controlled process, at short times. Structural rearrangements of the copolymer backbones are progressively more important as the adsorption carries on. The adsorption layers......, and the formed micelles appear to be elongated, interconnected and with larger thickness. As the transfer pressure increases, attractive micellar interactions are enhanced and then-lead to formation of a dense network of interconnected micelles, first followed by an evolvement to continent-like and dewetted...

  10. Molecular Evolution of PvMSP3α Block II in Plasmodium vivax from Diverse Geographic Origins.

    Directory of Open Access Journals (Sweden)

    Bhavna Gupta

    Full Text Available Block II of Plasmodium vivax merozoite surface protein 3α (PvMSP3α is conserved and has been proposed as a potential candidate for a malaria vaccine. The present study aimed to compare sequence diversity in PvMSP3a block II at a local microgeographic scale in a village as well as from larger geographic regions (countries and worldwide. Blood samples were collected from asymptomatic carriers of P. vivax in a village at the western border of Thailand and PvMSP3α was amplified and sequenced. For population genetic analysis, 237 PvMSP3α block II sequences from eleven P. vivax endemic countries were analyzed. PvMSP3α sequences from 20 village-level samples revealed two length variant types with one type containing a large deletion in block I. In contrast, block II was relatively conserved; especially, some non-synonymous mutations were extensively shared among 11 parasite populations. However, the majority of the low-frequency synonymous variations were population specific. The conserved pattern of nucleotide diversity in block II sequences was probably due to functional/structural constraints, which were further supported by the tests of neutrality. Notably, a small region in block II that encodes a predicted B cell epitope was highly polymorphic and showed signs of balancing selection, signifying that this region might be influenced by the immune selection and may serve as a starting point for designing multi-antigen/stage epitope based vaccines against this parasite.

  11. Down-Regulation of Complement Receptors on the Surface of Host Monocyte Even as In Vitro Complement Pathway Blocking Interferes in Dengue Infection

    Science.gov (United States)

    Marinho, Cintia Ferreira; Azeredo, Elzinandes Leal; Torrentes-Carvalho, Amanda; Marins-Dos-Santos, Alessandro; Kubelka, Claire Fernandes; de Souza, Luiz José; Cunha, Rivaldo Venâncio; de-Oliveira-Pinto, Luzia Maria

    2014-01-01

    In dengue virus (DENV) infection, complement system (CS) activation appears to have protective and pathogenic effects. In severe dengue fever (DF), the levels of DENV non-structural-1 protein and of the products of complement activation, including C3a, C5a and SC5b-9, are higher before vascular leakage occurs, supporting the hypothesis that complement activation contributes to unfavourable outcomes. The clinical manifestations of DF range from asymptomatic to severe and even fatal. Here, we aimed to characterise CS by their receptors or activation product, in vivo in DF patients and in vitro by DENV-2 stimulation on monocytes. In comparison with healthy controls, DF patients showed lower expression of CR3 (CD11b), CR4 (CD11c) and, CD59 on monocytes. The DF patients who were high producers of SC5b-9 were also those that showed more pronounced bleeding or vascular leakage. Those findings encouraged us to investigate the role of CS in vitro, using monocytes isolated from healthy subjects. Prior blocking with CR3 alone (CD11b) or CR3 (CD11b/CD18) reduced viral infection, as quantified by the levels of intracellular viral antigen expression and soluble DENV non-structural viral protein. However, we found that CR3 alone (CD11b) or CR3 (CD11b/CD18) blocking did not influence major histocompatibility complex presentation neither active caspase-1 on monocytes, thus probably ruling out inflammasome-related mechanisms. Although it did impair the secretion of tumour necrosis factor alpha and interferon alpha. Our data provide strategies of blocking CR3 (CD11b) pathways could have implications for the treatment of viral infection by antiviral-related mechanisms. PMID:25061945

  12. Down-regulation of complement receptors on the surface of host monocyte even as in vitro complement pathway blocking interferes in dengue infection.

    Directory of Open Access Journals (Sweden)

    Cintia Ferreira Marinho

    Full Text Available In dengue virus (DENV infection, complement system (CS activation appears to have protective and pathogenic effects. In severe dengue fever (DF, the levels of DENV non-structural-1 protein and of the products of complement activation, including C3a, C5a and SC5b-9, are higher before vascular leakage occurs, supporting the hypothesis that complement activation contributes to unfavourable outcomes. The clinical manifestations of DF range from asymptomatic to severe and even fatal. Here, we aimed to characterise CS by their receptors or activation product, in vivo in DF patients and in vitro by DENV-2 stimulation on monocytes. In comparison with healthy controls, DF patients showed lower expression of CR3 (CD11b, CR4 (CD11c and, CD59 on monocytes. The DF patients who were high producers of SC5b-9 were also those that showed more pronounced bleeding or vascular leakage. Those findings encouraged us to investigate the role of CS in vitro, using monocytes isolated from healthy subjects. Prior blocking with CR3 alone (CD11b or CR3 (CD11b/CD18 reduced viral infection, as quantified by the levels of intracellular viral antigen expression and soluble DENV non-structural viral protein. However, we found that CR3 alone (CD11b or CR3 (CD11b/CD18 blocking did not influence major histocompatibility complex presentation neither active caspase-1 on monocytes, thus probably ruling out inflammasome-related mechanisms. Although it did impair the secretion of tumour necrosis factor alpha and interferon alpha. Our data provide strategies of blocking CR3 (CD11b pathways could have implications for the treatment of viral infection by antiviral-related mechanisms.

  13. Ultrasound guided supraclavicular block.

    LENUS (Irish Health Repository)

    Hanumanthaiah, Deepak

    2013-09-01

    Ultrasound guided regional anaesthesia is becoming increasingly popular. The supraclavicular block has been transformed by ultrasound guidance into a potentially safe superficial block. We reviewed the techniques of performing supraclavicular block with special focus on ultrasound guidance.

  14. Maternally transmitted antibodies to pregnancy-associated variant antigens on the surface of erythrocytes infected with Plasmodium falciparum: relation to child susceptibility to malaria

    DEFF Research Database (Denmark)

    Cot, Michel; Le Hesran, Jean Yves; Staalsoe, Trine

    2003-01-01

    of antibodies in variable surface antigens (VSA) specific to chondroitin sulfate A (CSA)-binding parasites to assess the parasitologic status of the child. Flow cytometry was used to measure levels of antibodies to VSA from CSA-selected and -unselected parasite lines in the cord blood of 79 newborns in Ebolowa......, Cameroon. These newborns were subsequently followed up for 2 years to determine the date of first occurrence of blood parasites and mean parasite density during follow-up. Maternally transmitted antibodies to VSA expressed by CSA-binding parasites, but not antibodies to any other specificity, were...... negatively related to time of first appearance of Plasmodium falciparum in a child's blood and were positively related to mean parasite density during the first 2 years of life. If maternal infection is thought to be the main mechanism influencing susceptibility of the newborn to malaria, antibodies to VSA...

  15. Modeling Np and Pu transport with a surface complexation model and spatially variant sorption capacities: Implications for reactive transport modeling and performance assessments of nuclear waste disposal sites

    Science.gov (United States)

    Glynn, P.D.

    2003-01-01

    One-dimensional (1D) geochemical transport modeling is used to demonstrate the effects of speciation and sorption reactions on the ground-water transport of Np and Pu, two redox-sensitive elements. Earlier 1D simulations (Reardon, 1981) considered the kinetically limited dissolution of calcite and its effect on ion-exchange reactions (involving 90Sr, Ca, Na, Mg and K), and documented the spatial variation of a 90Sr partition coefficient under both transient and steady-state chemical conditions. In contrast, the simulations presented here assume local equilibrium for all reactions, and consider sorption on constant potential, rather than constant charge, surfaces. Reardon's (1981) seminal findings on the spatial and temporal variability of partitioning (of 90Sr) are reexamined and found partially caused by his assumption of a kinetically limited reaction. In the present work, sorption is assumed the predominant retardation process controlling Pu and Np transport, and is simulated using a diffuse-double-layer-surface-complexation (DDLSC) model. Transport simulations consider the infiltration of Np- and Pu-contaminated waters into an initially uncontaminated environment, followed by the cleanup of the resultant contamination with uncontaminated water. Simulations are conducted using different spatial distributions of sorption capacities (with the same total potential sorption capacity, but with different variances and spatial correlation structures). Results obtained differ markedly from those that would be obtained in transport simulations using constant Kd, Langmuir or Freundlich sorption models. When possible, simulation results (breakthrough curves) are fitted to a constant K d advection-dispersion transport model and compared. Functional differences often are great enough that they prevent a meaningful fit of the simulation results with a constant K d (or even a Langmuir or Freundlich) model, even in the case of Np, a weakly sorbed radionuclide under the

  16. Homogeneous bilateral block shifts

    Indian Academy of Sciences (India)

    Douglas class were classified in [3]; they are unilateral block shifts of arbitrary block size (i.e. dim H(n) can be anything). However, no examples of irreducible homogeneous bilateral block shifts of block size larger than 1 were known until now.

  17. Block copolymer investigations

    Science.gov (United States)

    Yufa, Nataliya A.

    The research presented in this thesis deals with various aspects of block copolymers on the nanoscale: their behavior at a range of temperatures, their use as scaffolds, or for creation of chemically striped surfaces, as well as the behavior of metals on block copolymers under the influence of UV light, and the healing behavior of copolymers. Invented around the time of World War II, copolymers have been used for decades due to their macroscopic properties, such as their ability to be molded without vulcanization, and the fact that, unlike rubber, they can be recycled. In recent years, block copolymers (BCPs) have been used for lithography, as scaffolds for nano-objects, to create a magnetic hard drive, as well as in photonic and other applications. In this work we used primarily atomic force microscopy (AFM) and transmission electron microscopy (TEM), described in Chapter II, to conduct our studies. In Chapter III we demonstrate a new and general method for positioning nanoparticles within nanoscale grooves. This technique is suitable for nanodots, nanocrystals, as well as DNA. We use AFM and TEM to demonstrate selective decoration. In Chapters IV and V we use AFM and TEM to study the structure of polymer surfaces coated with metals and self-assembled monolayers. We describe how the surfaces were created, exhibit their structure on the nanoscale, and prove that their macroscopic wetting properties have been altered compared to the original polymer structures. Finally, Chapters VI and VII report out in-situ AFM studies of BCP at high temperatures, made possible only recently with the invention of air-tight high-temperature AFM imaging cells. We locate the transition between disordered films and cylinders during initial ordering. Fluctuations of existing domains leading to domain coarsening are also described, and are shown to be consistent with reptation and curvature minimization. Chapter VII deals with the healing of PS-b-PMMA following AFM-tip lithography or

  18. Hemoglobin Variants in Mice

    Energy Technology Data Exchange (ETDEWEB)

    Popp, Raymond A.

    1965-04-22

    Variability among mammalian hemoglobins was observed many years ago (35). The chemical basis for differences among hemoglobins from different species of mammals has been studied by several investigators (5, 11, 18, 48). As well as interspecies differences, hemoglobin variants are frequently found within a species of mammals (2, 3, 7, 16) The inheritance of these intraspecies variants can be studied, and pedigrees indicate that the type of hemoglobin synthesized in an individual is genetically controlled (20). Several of the variant human hemoglobins are f'unctionally deficient (7, 16). Such hemoglobin anomalies are of basic interest to man because of the vital role of hemoglobin for transporting oxygen to all tissues of the body.

  19. Collisions of Slow Polyatomic Ions with Surfaces: Dissociation and Chemical Reactions of CD5+, CD4+, CD3+ and Their Isotopic Variants on Room-Temperature and Heated Carbon Surfaces

    Czech Academy of Sciences Publication Activity Database

    Roithová, Jana; Žabka, Ján; Dolejšek, Zdeněk; Herman, Zdeněk

    2002-01-01

    Roč. 106, - (2002), s. 8293-8301 ISSN 1089-5647 R&D Projects: GA ČR GA203/00/0632 Institutional research plan: CEZ:AV0Z4040901 Keywords : liquid surface * scattering * energies Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.611, year: 2002

  20. Plasma antibodies from malaria-exposed pregnant women recognize variant surface antigens on Plasmodium falciparum-infected erythrocytes in a parity-dependent manner and block parasite adhesion to chondroitin sulfate A

    DEFF Research Database (Denmark)

    Ricke, C H; Staalsoe, T; Koram, K

    2000-01-01

    -associated malaria (PAM) in endemic areas is concentrated in the first few pregnancies, indicating that protective immunity to PAM is a function of parity. The placenta is often heavily infected in PAM, and placental parasites show a striking preference for chondroitin sulfate A (CSA) as an adhesion receptor. Plasma...

  1. Kaposi's sarcoma-associated herpesvirus encodes two proteins that block cell surface display of MHC class I chains by enhancing their endocytosis

    OpenAIRE

    Coscoy, Laurent; Ganem, Don

    2000-01-01

    Down-regulation of the cell surface display of class I MHC proteins is an important mechanism of immune evasion by human and animal viruses. Herpesviruses in particular encode a variety of proteins that function to lower MHC I display by several mechanisms. These include binding and retention of MHC I chains in the endoplasmic reticulum, dislocation of class I chains from the ER, inhibition of the peptide transporter (TAP) involved in antigen presentation, and shunting of newly assembled chai...

  2. Kaposi's sarcoma-associated herpesvirus encodes two proteins that block cell surface display of MHC class I chains by enhancing their endocytosis.

    Science.gov (United States)

    Coscoy, L; Ganem, D

    2000-07-05

    Down-regulation of the cell surface display of class I MHC proteins is an important mechanism of immune evasion by human and animal viruses. Herpesviruses in particular encode a variety of proteins that function to lower MHC I display by several mechanisms. These include binding and retention of MHC I chains in the endoplasmic reticulum, dislocation of class I chains from the ER, inhibition of the peptide transporter (TAP) involved in antigen presentation, and shunting of newly assembled chains to lysosomes. Kaposi's sarcoma (KS)-associated herpesvirus (KSHV) is a human herpesvirus strongly linked to the development of KS and to certain AIDS-associated lymphoproliferative disorders. Here we show that KSHV encodes two distinctive gene products that function to dramatically reduce cell surface MHC I expression. These viral proteins are localized predominantly to the ER. However, unlike previously described MHC I inhibitors, they do not interfere with the synthesis, translocation, or assembly of class I chains, nor do they retain them in the ER. Rather, they act to enhance endocytosis of MHC I from the cell surface; internalized class I chains are delivered to endolysosomal vesicles, where they undergo degradation. These KSHV proteins define a mechanism of class I down-regulation distinct from the mechanisms of other herpesviruses and are likely to contribute importantly to immune evasion during viral infection.

  3. Plasmodium falciparum merozoite surface protein 1 block 2 gene polymorphism in field isolates along the slope of mount Cameroon: a cross - sectional study.

    Science.gov (United States)

    Apinjoh, Tobias O; Tata, Rolland B; Anchang-Kimbi, Judith K; Chi, Hanesh F; Fon, Eleanor M; Mugri, Regina N; Tangoh, Delphine A; Nyingchu, Robert V; Ghogomu, Stephen M; Nkuo-Akenji, Theresa; Achidi, Eric A

    2015-08-05

    Malaria remains a major global health burden despite the intensification of control efforts, due partly to the lack of an effective vaccine. Information on genetic diversity in natural parasite populations constitutes a major impediment to vaccine development efforts and is limited in some endemic settings. The present study characterized diversity by investigating msp1 block 2 polymorphisms and the relationship between the allele families with ethnodemographic indices and clinical phenotype. Individuals with asymptomatic parasitaemia (AP) or uncomplicated malaria (UM) were enrolled from rural, semi-rural and semi-urban localities at varying altitudes along the slope of mount Cameroon. P. falciparum malaria parasitaemic blood screened by light microscopy was depleted of leucocytes using CF11 cellulose columns and the parasite DNA genotyped by nested PCR. Length polymorphism was assessed in 151 field isolates revealing 64 (5) and 274 (22) distinct recombinant and major msp1 allelic fragments (genotypes) respectively. All family specific allelic types (K1, MAD20 and RO33) as well as MR were observed in the different locations, with K1 being most abundant. Eighty seven (60 %) of individuals harbored more than one parasite clone, with a significant proportion (p = 0.009) in rural compared to other settings. AP individuals had higher (p = 0.007) K1 allele frequencies but lower (p = 0.003) mean multiplicity of genotypes per infection (2.00 ± 0.98 vs. 2.56 ± 1.17) compared to UM patients. These results indicate enormous diversity of P. falciparum in the area and suggests that allele specificity and complexity may be relevant for the progression to symptomatic disease.

  4. Histone variants and lipid metabolism

    NARCIS (Netherlands)

    Borghesan, Michela; Mazzoccoli, Gianluigi; Sheedfar, Fareeba; Oben, Jude; Pazienza, Valerio; Vinciguerra, Manlio

    2014-01-01

    Within nucleosomes, canonical histones package the genome, but they can be opportunely replaced with histone variants. The incorporation of histone variants into the nucleosome is a chief cellular strategy to regulate transcription and cellular metabolism. In pathological terms, cellular steatosis

  5. Homogeneous bilateral block shifts

    Indian Academy of Sciences (India)

    A new 3-parameter family of homogeneous 2-by-2 block shifts is described. These are the first examples of irreducible homogeneous bilateral block shifts of block size larger than 1. Author Affiliations. Adam Korányi1. Department of Mathematics, The Graduate Center, City University of New York, New York, NY 10016, USA ...

  6. 16α-Hydroxyfriedelin and 3-Oxo-16-methylfriedel-16-ene as Building Blocks: Crystal Structure and Hirshfeld Surfaces Decoding Intermolecular Contacts

    Directory of Open Access Journals (Sweden)

    Rodrigo S. Corrêa

    2013-01-01

    Full Text Available In this paper the importance of C–H⋯O intermolecular hydrogen bonds and van der Waals forces in crystal packing stabilization of 16α-hydroxyfriedelin (1 and 3-oxo-16-methylfriedel-16-ene (2 is described. Compound 1 is a natural product isolated from the hexane extract of Salacia elliptica branches, whereas compound 2 is obtained from compound 1 after dehydration accompanied by methyl migration of C-17 to C-16. The single-crystal X-ray diffraction experiments for 1 and 2 were carried out at 150 K, and the crystallographic study demonstrated that these compounds crystallize in noncentrosymmetric space groups, with 1 showing an orthorhombic P212121 space group and 2 a monoclinic P21 one. Compounds 1 and 2 are composed of five fused six-membered rings presenting a chair conformation, except for the central ring of 2, which adopts a half-chair conformation. In addition, the intra- and intermolecular parameters were studied using CCDC MOGUL analyses and Hirshfeld surfaces.

  7. Blocking contacts for N-type cadmium zinc telluride

    Science.gov (United States)

    Stahle, Carl M. (Inventor); Parker, Bradford H. (Inventor); Babu, Sachidananda R. (Inventor)

    2012-01-01

    A process for applying blocking contacts on an n-type CdZnTe specimen includes cleaning the CdZnTe specimen; etching the CdZnTe specimen; chemically surface treating the CdZnTe specimen; and depositing blocking metal on at least one of a cathode surface and an anode surface of the CdZnTe specimen.

  8. Variants of glycoside hydrolases

    Energy Technology Data Exchange (ETDEWEB)

    Teter, Sarah; Ward, Connie; Cherry, Joel; Jones, Aubrey; Harris, Paul; Yi, Jung

    2017-07-11

    The present invention relates to variants of a parent glycoside hydrolase, comprising a substitution at one or more positions corresponding to positions 21, 94, 157, 205, 206, 247, 337, 350, 373, 383, 438, 455, 467, and 486 of amino acids 1 to 513 of SEQ ID NO: 2, and optionally further comprising a substitution at one or more positions corresponding to positions 8, 22, 41, 49, 57, 113, 193, 196, 226, 227, 246, 251, 255, 259, 301, 356, 371, 411, and 462 of amino acids 1 to 513 of SEQ ID NO: 2 a substitution at one or more positions corresponding to positions 8, 22, 41, 49, 57, 113, 193, 196, 226, 227, 246, 251, 255, 259, 301, 356, 371, 411, and 462 of amino acids 1 to 513 of SEQ ID NO: 2, wherein the variants have glycoside hydrolase activity. The present invention also relates to nucleotide sequences encoding the variant glycoside hydrolases and to nucleic acid constructs, vectors, and host cells comprising the nucleotide sequences.

  9. Variants of glycoside hydrolases

    Science.gov (United States)

    Teter, Sarah; Ward, Connie; Cherry, Joel; Jones, Aubrey; Harris, Paul; Yi, Jung

    2013-02-26

    The present invention relates to variants of a parent glycoside hydrolase, comprising a substitution at one or more positions corresponding to positions 21, 94, 157, 205, 206, 247, 337, 350, 373, 383, 438, 455, 467, and 486 of amino acids 1 to 513 of SEQ ID NO: 2, and optionally further comprising a substitution at one or more positions corresponding to positions 8, 22, 41, 49, 57, 113, 193, 196, 226, 227, 246, 251, 255, 259, 301, 356, 371, 411, and 462 of amino acids 1 to 513 of SEQ ID NO: 2 a substitution at one or more positions corresponding to positions 8, 22, 41, 49, 57, 113, 193, 196, 226, 227, 246, 251, 255, 259, 301, 356, 371, 411, and 462 of amino acids 1 to 513 of SEQ ID NO: 2, wherein the variants have glycoside hydrolase activity. The present invention also relates to nucleotide sequences encoding the variant glycoside hydrolases and to nucleic acid constructs, vectors, and host cells comprising the nucleotide sequences.

  10. [Clinico-pathogenetic variants of chronic gastritis].

    Science.gov (United States)

    Chernin, V V; Dzhulaĭ, G S

    2004-01-01

    To evaluate specific features of the course of chronic gastritis (CG), morphofunctional condition of gastric mucosa, vegetative regulation, adrenergic and cholinergic shifts, histamine metabolism and effects of exogenic and endogenic risk factors in CG patients; to study clinicopathogenetic variants of CG. A total of 311 CG patients aged from 16 to 72 years were studied. They were divided into three groups by their gastric mucosa condition. The control group consisted of 30 healthy donors. The following parameters were studied: visual and histological condition of gastric mucosa, total acidity, the levels of free hydrochloric acid, pepsin, bioelectric gastric activity, general autonomic tonicity, cholinesterase activity. Three clinicopathogenetic variants of the disease have been identified. Variant 1 was characterized by a recurrent course, subjective manifestation of the disease only in exacerbation, surface (primarily antral) mucosal affection, normal or enhanced secretory and motor functions of the stomach, adequate reaction of acid production to caffeine and histamine stimulation, parasympathicotonia, absolute hyperhistaminemia, relative hypoacetylcholinemia, subnormal urinary excretion of adrenalin. Variant 2 manifested with rare recurrences, longer and more severe exacerbations, frequent spontaneous and provoked aggravations, moderate focal atrophy of the mucosa, secretory insufficiency with adequate reaction to histamine and minor to caffeine stimuli, hypomotor gastric dyskinesia, vegetative eutonia, normohistaminemia, absolute hypoacetylcholinemia, subnormal urinary excretion of noradrenaline. Variant 3 runs without definite remissions and exacerbations, with continuous abdominal pain and dyspepsia, frequent spontaneous aggravations, marked extended mucosal atrophy with secretory insufficiency up to achlorhydria, no stimulation of acid production in response to caffeine and histamine, gastric hypomotility, sympathicotonia, absolute hypohistaminemia

  11. Blocked Randomization with Randomly Selected Block Sizes

    Directory of Open Access Journals (Sweden)

    Jimmy Efird

    2010-12-01

    Full Text Available When planning a randomized clinical trial, careful consideration must be given to how participants are selected for various arms of a study. Selection and accidental bias may occur when participants are not assigned to study groups with equal probability. A simple random allocation scheme is a process by which each participant has equal likelihood of being assigned to treatment versus referent groups. However, by chance an unequal number of individuals may be assigned to each arm of the study and thus decrease the power to detect statistically significant differences between groups. Block randomization is a commonly used technique in clinical trial design to reduce bias and achieve balance in the allocation of participants to treatment arms, especially when the sample size is small. This method increases the probability that each arm will contain an equal number of individuals by sequencing participant assignments by block. Yet still, the allocation process may be predictable, for example, when the investigator is not blind and the block size is fixed. This paper provides an overview of blocked randomization and illustrates how to avoid selection bias by using random block sizes.

  12. Blocked randomization with randomly selected block sizes.

    Science.gov (United States)

    Efird, Jimmy

    2011-01-01

    When planning a randomized clinical trial, careful consideration must be given to how participants are selected for various arms of a study. Selection and accidental bias may occur when participants are not assigned to study groups with equal probability. A simple random allocation scheme is a process by which each participant has equal likelihood of being assigned to treatment versus referent groups. However, by chance an unequal number of individuals may be assigned to each arm of the study and thus decrease the power to detect statistically significant differences between groups. Block randomization is a commonly used technique in clinical trial design to reduce bias and achieve balance in the allocation of participants to treatment arms, especially when the sample size is small. This method increases the probability that each arm will contain an equal number of individuals by sequencing participant assignments by block. Yet still, the allocation process may be predictable, for example, when the investigator is not blind and the block size is fixed. This paper provides an overview of blocked randomization and illustrates how to avoid selection bias by using random block sizes.

  13. 31 CFR 595.301 - Blocked account; blocked property.

    Science.gov (United States)

    2010-07-01

    ... (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY TERRORISM SANCTIONS REGULATIONS General Definitions § 595.301 Blocked account; blocked property. The terms blocked account and blocked...

  14. Neuromuscular Activity of Upper and Lower Limbs during two Backstroke Swimming Start Variants.

    Science.gov (United States)

    De Jesus, Karla; De Jesus, Kelly; Medeiros, Alexandre I A; Gonçalves, Pedro; Figueiredo, Pedro; Fernandes, Ricardo J; Vilas-Boas, João Paulo

    2015-09-01

    A proficient start is decisive in sprint competitive swimming events and requires swimmers' to exert maximal forces in a short period to complete the task successfully. The aim of this study was to compare the electromyographic (EMG) activity in-between the backstroke start with feet positioned parallel and partially emerged performed with the hands on the highest horizontal and on the vertical handgrip at hands-off, take-off, flight and entry start phases. EMG comparisons between starting variants were supported by upper and lower limb joint angles at starting position and 15 m start time data. Following a four-week start training to familiarize participants with each start variant, 10 male competitive backstroke swimmers performed randomly six 15 m maximal trials, being three of each start variant. Surface EMG of Biceps Brachii, Triceps Brachii, Rectus Femoris, Biceps Femoris, Gastrocnemius Medialis and Tibialis Anterior was recorded and processed using the time integral EMG (iEMG). Eight video cameras (four surface and four underwater) were used to determine backstroke start phases and joint angles at starting position. EMG, joint angles and temporal parameters have not evidenced changes due to the different handgrips. Nevertheless, clear differences were observed in both variants for upper and lower limb muscles activity among starting phases (e.g. Biceps Brachii at take-off vs. flight phase, 15.17% ± 2.76% and 22.38% ± 4.25%; 14.24% ± 7.11% and 25.90% ± 8.65%, for variant with hands horizontal and vertically positioned, respectively). It was concluded that different handgrips did not affect EMG, kinematics and temporal profile in backstroke start. Despite coaches might plan similar strength training for both start variants, further attention should be given on the selection of proper exercises to maximize the contribution of relevant muscles at different starting phases. Key pointsAn effective swim start component (from the starting signal until the

  15. A Functional Assay for Sick Sinus Syndrome Genetic Variants

    Directory of Open Access Journals (Sweden)

    Chuanchau J. Jou

    2017-08-01

    Full Text Available Background/Aims: Congenital Sick Sinus Syndrome (SSS is a disorder associated with sudden cardiac death due to severe bradycardia and prolonged pauses. Mutations in HCN4, the gene encoding inward Na+/K+ current (If, have been described as a cause of congenital SSS. The objective of this study is to develop an SSS model in embryonic zebrafish, and use zebrafish as a moderate-throughput assay to functionally characterize HCN4 variants. Methods: To determine the function of hcn4 in zebrafish, embryos were either bathed in the If -specific blocker (ZD-7288, or endogenous hcn4 expression was knocked down using splice-blocking morpholinos. To assess whether the zebrafish model discriminates benign from pathogenic variants, we tested four HCN4 mutations known to cause human SSS and four variants of unknown significance (VUS. Results: Pharmacological blockade and knockdown of hcn4 in zebrafish phenocopied human SSS, displaying bradycardia and cardiac pauses in intact embryos and explanted hearts. The zebrafish assay correctly identified all disease-causing variants. Of the VUS, the assay predicted 2 as benign and 2 as hypomorphic variants. Conclusions: We conclude that our embryonic zebrafish assay is a novel and effective tool to functionally characterize human HCN4 variants, which can be translated into important clinical prognostic information.

  16. Generalized Block Failure

    DEFF Research Database (Denmark)

    Jönsson, Jeppe

    2015-01-01

    Block tearing is considered in several codes as a pure block tension or a pure block shear failure mechanism. However in many situations the load acts eccentrically and involves the transfer of a substantial moment in combination with the shear force and perhaps a normal force. A literature study...... shows that no readily available tests with a well-defined substantial eccentricity have been performed. This paper presents theoretical and experimental work leading towards generalized block failure capacity methods. Simple combination of normal force, shear force and moment stress distributions along...

  17. A 3-Subset Meet-in-the-Middle Attack: Cryptanalysis of the Lightweight Block Cipher KTANTAN

    DEFF Research Database (Denmark)

    Bogdanov, Andrey; Rechberger, Christian

    2011-01-01

    In this paper we describe a variant of existing meet-in-the-middle attacks on block ciphers. As an application, we propose meet-in-the-middle attacks that are applicable to the KTANTAN family of block ciphers accepting a key of 80 bits. The attacks are due to sonic weaknesses in its bitwise key...

  18. Homogeneous bilateral block shifts

    Indian Academy of Sciences (India)

    Homogeneous bilateral block shifts. ADAM KORÁNYI. Department of Mathematics, The Graduate Center, City University of New York,. New York, NY 10016, USA. E-mail: Adam.Koranyi@lehman.cuny.edu. MS received 18 January 2013. Abstract. A new 3-parameter family of homogeneous 2-by-2 block shifts is described.

  19. Related Drupal Nodes Block

    NARCIS (Netherlands)

    Van der Vegt, Wim

    2010-01-01

    Related Drupal Nodes Block This module exposes a block that uses Latent Semantic Analysis (Lsa) internally to suggest three nodes that are relevant to the node a user is viewing. This module performs three tasks. 1) It periodically indexes a Drupal site and generates a Lsa Term Document Matrix.

  20. Control rod blocking monitor

    International Nuclear Information System (INIS)

    Suzuki, Shigeru.

    1993-01-01

    The number of times for setting up a control rod blocking monitor of a BWR type power plant is remarkably reduced to mitigate operator's burden. In the control rod blocking monitor, trip levels, as a judging standard upon outputting control rod blocking inhibition signals, are set up stepwise depending on the power level around control rods put to blocking control. The present invention comprises an allowance judging means capable of setting up trip levels for each of power levels corresponding to a plurality of control rods at once if the power levels are within the set up allowable range. With such a constitution, the set up allowable range is determined previously in the allowance judging means. Accordingly, when a gang blocking is conducted to control rods, if power levels around the control rods are increased at once into the set up allowable range, the trip levels for each of the control rods are set up at once. (I.S.)

  1. Ground reaction curve based upon block theory

    International Nuclear Information System (INIS)

    Yow, J.L. Jr.; Goodman, R.E.

    1985-09-01

    Discontinuities in a rock mass can intersect an excavation surface to form discrete blocks (keyblocks) which can be unstable. Once a potentially unstable block is identified, the forces affecting it can be calculated to assess its stability. The normal and shear stresses on each block face before displacement are calculated using elastic theory and are modified in a nonlinear way by discontinuity deformations as the keyblock displaces. The stresses are summed into resultant forces to evaluate block stability. Since the resultant forces change with displacement, successive increments of block movement are examined to see whether the block ultimately becomes stable or fails. Two-dimensional (2D) and three-dimensional (3D) analytic models for the stability of simple pyramidal keyblocks were evaluated. Calculated stability is greater for 3D analyses than for 2D analyses. Calculated keyblock stability increases with larger in situ stress magnitudes, larger lateral stress ratios, and larger shear strengths. Discontinuity stiffness controls blocks displacement more strongly than it does stability itself. Large keyblocks are less stable than small ones, and stability increases as blocks become more slender

  2. Predictability of blocking

    International Nuclear Information System (INIS)

    Tosi, E.; Ruti, P.; Tibaldi, S.; D'Andrea, F.

    1994-01-01

    Tibaldi and Molteni (1990, hereafter referred to as TM) had previously investigated operational blocking predictability by the ECMWF model and the possible relationships between model systematic error and blocking in the winter season of the Northern Hemisphere, using seven years of ECMWF operational archives of analyses and day 1 to 10 forecasts. They showed that fewer blocking episodes than in the real atmosphere were generally simulated by the model, and that this deficiency increased with increasing forecast time. As a consequence of this, a major contribution to the systematic error in the winter season was shown to derive from the inability of the model to properly forecast blocking. In this study, the analysis performed in TM for the first seven winter seasons of the ECMWF operational model is extended to the subsequent five winters, during which model development, reflecting both resolution increases and parametrisation modifications, continued unabated. In addition the objective blocking index developed by TM has been applied to the observed data to study the natural low frequency variability of blocking. The ability to simulate blocking of some climate models has also been tested

  3. 31 CFR 594.301 - Blocked account; blocked property.

    Science.gov (United States)

    2010-07-01

    ... (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY GLOBAL TERRORISM SANCTIONS REGULATIONS General Definitions § 594.301 Blocked account; blocked property. The terms blocked account and...

  4. Bundle Branch Block

    Science.gov (United States)

    ... 2015. Bundle branch block Symptoms & causes Diagnosis & treatment Advertisement Mayo Clinic does not endorse companies or products. ... a Job Site Map About This Site Twitter Facebook Google YouTube Pinterest Mayo Clinic is a not- ...

  5. Blocked Urethral Valves

    Science.gov (United States)

    ... the penis. Rarely, small membranes form across the urethra in boys early in pregnancy, and they can block the flow of urine out of the bladder. These membranes are called posterior urethral valves and can have life-threatening consequences ...

  6. Optoelectronics using block copolymers.

    Energy Technology Data Exchange (ETDEWEB)

    Botiz, I.; Darling, S. B.; Center for Nanoscale Materials

    2010-05-01

    Block copolymers, either as semiconductors themselves or as structure directors, are emerging as a promising class of materials for understanding and controlling processes associated with both photovoltaic energy conversion and light emitting devices.

  7. UAV PHOTOGRAMMETRY: BLOCK TRIANGULATION COMPARISONS

    Directory of Open Access Journals (Sweden)

    R. Gini

    2013-08-01

    Full Text Available UAVs systems represent a flexible technology able to collect a big amount of high resolution information, both for metric and interpretation uses. In the frame of experimental tests carried out at Dept. ICA of Politecnico di Milano to validate vector-sensor systems and to assess metric accuracies of images acquired by UAVs, a block of photos taken by a fixed wing system is triangulated with several software. The test field is a rural area included in an Italian Park ("Parco Adda Nord", useful to study flight and imagery performances on buildings, roads, cultivated and uncultivated vegetation. The UAV SenseFly, equipped with a camera Canon Ixus 220HS, flew autonomously over the area at a height of 130 m yielding a block of 49 images divided in 5 strips. Sixteen pre-signalized Ground Control Points, surveyed in the area through GPS (NRTK survey, allowed the referencing of the block and accuracy analyses. Approximate values for exterior orientation parameters (positions and attitudes were recorded by the flight control system. The block was processed with several software: Erdas-LPS, EyeDEA (Univ. of Parma, Agisoft Photoscan, Pix4UAV, in assisted or automatic way. Results comparisons are given in terms of differences among digital surface models, differences in orientation parameters and accuracies, when available. Moreover, image and ground point coordinates obtained by the various software were independently used as initial values in a comparative adjustment made by scientific in-house software, which can apply constraints to evaluate the effectiveness of different methods of point extraction and accuracies on ground check points.

  8. Variant (Swine Origin) Influenza Viruses in Humans

    Science.gov (United States)

    ... Types Seasonal Avian Swine Variant Other Variant Influenza Viruses: Background and CDC Risk Assessment and Reporting Language: ... Background CDC Assessment Reporting Background On Variant Influenza Viruses Swine flu viruses do not normally infect humans. ...

  9. Identifying rare variants with optimal depth of coverage and cost-effective overlapping pool sequencing.

    Science.gov (United States)

    Cao, Chang-Chang; Li, Cheng; Huang, Zheng; Ma, Xin; Sun, Xiao

    2013-12-01

    Genome-wide association studies have identified hundreds of genetic variants associated with complex diseases although most variants identified so far explain only a small proportion of heritability, suggesting that rare variants are responsible for missing heritability. Identification of rare variants through large-scale resequencing becomes increasing important but still prohibitively expensive despite the rapid decline in the sequencing costs. Nevertheless, group testing based overlapping pool sequencing in which pooled rather than individual samples are sequenced will greatly reduces the efforts of sample preparation as well as the costs to screen for rare variants. Here, we proposed an overlapping pool sequencing to screen rare variants with optimal sequencing depth and a corresponding cost model. We formulated a model to compute the optimal depth for sufficient observations of variants in pooled sequencing. Utilizing shifted transversal design algorithm, appropriate parameters for overlapping pool sequencing could be selected to minimize cost and guarantee accuracy. Due to the mixing constraint and high depth for pooled sequencing, results showed that it was more cost-effective to divide a large population into smaller blocks which were tested using optimized strategies independently. Finally, we conducted an experiment to screen variant carriers with frequency equaled 1%. With simulated pools and publicly available human exome sequencing data, the experiment achieved 99.93% accuracy. Utilizing overlapping pool sequencing, the cost for screening variant carriers with frequency equaled 1% in 200 diploid individuals dropped to at least 66% at which target sequencing region was set to 30 Mb. © 2013 WILEY PERIODICALS, INC.

  10. Variants of beta-glucosidases

    Science.gov (United States)

    Fidantsef, Ana; Lamsa, Michael; Gorre-Clancy, Brian

    2014-10-07

    The present invention relates to variants of a parent beta-glucosidase, comprising a substitution at one or more positions corresponding to positions 142, 183, 266, and 703 of amino acids 1 to 842 of SEQ ID NO: 2 or corresponding to positions 142, 183, 266, and 705 of amino acids 1 to 844 of SEQ ID NO: 70, wherein the variant has beta-glucosidase activity. The present invention also relates to nucleotide sequences encoding the variant beta-glucosidases and to nucleic acid constructs, vectors, and host cells comprising the nucleotide sequences.

  11. Variants of beta-glucosidase

    Science.gov (United States)

    Fidantsef, Ana [Davis, CA; Lamsa, Michael [Davis, CA; Gorre-Clancy, Brian [Elk Grove, CA

    2009-12-29

    The present invention relates to variants of a parent beta-glucosidase, comprising a substitution at one or more positions corresponding to positions 142, 183, 266, and 703 of amino acids 1 to 842 of SEQ ID NO: 2 or corresponding to positions 142, 183, 266, and 705 of amino acids 1 to 844 of SEQ ID NO: 70, wherein the variant has beta-glucosidase activity. The present invention also relates to nucleotide sequences encoding the variant beta-glucosidases and to nucleic acid constructs, vectors, and host cells comprising the nucleotide sequences.

  12. Right bundle branch block

    DEFF Research Database (Denmark)

    Bussink, Barbara E; Holst, Anders Gaarsdal; Jespersen, Lasse

    2013-01-01

    AimsTo determine the prevalence, predictors of newly acquired, and the prognostic value of right bundle branch block (RBBB) and incomplete RBBB (IRBBB) on a resting 12-lead electrocardiogram in men and women from the general population.Methods and resultsWe followed 18 441 participants included.......5%/2.3% in women, P Right bundle branch block was associated with significantly...... increased all-cause and cardiovascular mortality in both genders with age-adjusted hazard ratios (HR) of 1.31 [95% confidence interval (CI), 1.11-1.54] and 1.87 (95% CI, 1.48-2.36) in the gender pooled analysis with little attenuation after multiple adjustment. Right bundle branch block was associated...

  13. Contaminated soil concrete blocks

    NARCIS (Netherlands)

    de Korte, A.C.J.; Brouwers, Jos; Limbachiya, Mukesh C.; Kew, Hsein Y.

    2009-01-01

    According to Dutch law the contaminated soil needs to be remediated or immobilised. The main focus in this article is the design of concrete blocks, containing contaminated soil, that are suitable for large production, financial feasible and meets all technical and environmental requirements. In

  14. Making Block Grants Accountable.

    Science.gov (United States)

    Chelimsky, Eleanor

    Methods of accountability are presented in considering the Reagan administration plan to consolidate 84 federal health, education and social service grants into six block grant areas and to cut overall funding. After matching aspects of public criticism with proposal objectives, a rationale is developed for building elements of accountability into…

  15. Linoleum Block Printing Revisited.

    Science.gov (United States)

    Chetelat, Frank J.

    1980-01-01

    The author discusses practical considerations of teaching linoleum block printing in the elementary grades (tool use, materials, motivation) and outlines a sequence of design concepts in this area for the primary, intermediate and junior high grades. A short list of books and audiovisual aids is appended. (SJL)

  16. Effects of Block Scheduling

    Directory of Open Access Journals (Sweden)

    William R. Veal

    1999-09-01

    Full Text Available This study examined the effects of a tri-schedule on the academic achievement of students in a high school. The tri-schedule consists of traditional, 4x4 block, and hybrid schedules running at the same time in the same high school. Effectiveness of the schedules was determined from the state mandated test of basic skills in reading, language, and mathematics. Students who were in a particular schedule their freshman year were tested at the beginning of their sophomore year. A statistical ANCOVA test was performed using the schedule types as independent variables and cognitive skill index and GPA as covariates. For reading and language, there was no statistically significant difference in test results. There was a statistical difference mathematics-computation. Block mathematics is an ideal format for obtaining more credits in mathematics, but the block format does little for mathematics achievement and conceptual understanding. The results have content specific implications for schools, administrations, and school boards who are considering block scheduling adoption.

  17. Coding with Blockly

    CERN Document Server

    Lovett, Amber

    2017-01-01

    "Blockly is a fun, graphical programming language designed to get kids interested in creating their own computer programs. Through simple text written to foster creativity and problem solving, students will the art of innovation. Large, colorful images show students how to complete activities. Additional tools, including a glossary and an index, help students learn new vocabulary and locate information."-- Provided by publisher.

  18. Amino acid changes in disease-associated variants differ radically from variants observed in the 1000 genomes project dataset.

    Directory of Open Access Journals (Sweden)

    Tjaart A P de Beer

    Full Text Available The 1000 Genomes Project data provides a natural background dataset for amino acid germline mutations in humans. Since the direction of mutation is known, the amino acid exchange matrix generated from the observed nucleotide variants is asymmetric and the mutabilities of the different amino acids are very different. These differences predominantly reflect preferences for nucleotide mutations in the DNA (especially the high mutation rate of the CpG dinucleotide, which makes arginine mutability very much higher than other amino acids rather than selection imposed by protein structure constraints, although there is evidence for the latter as well. The variants occur predominantly on the surface of proteins (82%, with a slight preference for sites which are more exposed and less well conserved than random. Mutations to functional residues occur about half as often as expected by chance. The disease-associated amino acid variant distributions in OMIM are radically different from those expected on the basis of the 1000 Genomes dataset. The disease-associated variants preferentially occur in more conserved sites, compared to 1000 Genomes mutations. Many of the amino acid exchange profiles appear to exhibit an anti-correlation, with common exchanges in one dataset being rare in the other. Disease-associated variants exhibit more extreme differences in amino acid size and hydrophobicity. More modelling of the mutational processes at the nucleotide level is needed, but these observations should contribute to an improved prediction of the effects of specific variants in humans.

  19. Variant (Prinzmetal's) Form of Angina Pectoris Manifesting in ...

    African Journals Online (AJOL)

    1974-06-08

    , which has been termed the variant or atypical form of angina pectoris. The distribution of the pain is identical with the classic form of angina pectoris, being substernal with radiation to the jaw and down the ulnar surfaces of ...

  20. Compaction of bentonite blocks. Development of techniques for production of blocks with different shapes and sizes

    International Nuclear Information System (INIS)

    Johannesson, Lars-Erik; Boergesson, Lennart

    1998-09-01

    In this report useful techniques for producing both smaller blocks manageable by man (10-15 kg) and larger blocks which need special equipment for handling (weight up to 600 kg) are described. Tests for producing blocks with a weight of approximately 10 kg were carried out at Hoeganaes Bjuf AB in Bjuv. This industry is normally producing refractory bricks and other refractory products. The plant has facilities for handling large volumes of clay. It also has machines suitable for producing uniaxially compacted blocks. Tests performed at the plant show that it is possible to compact blocks with good quality. The best quality was reached with a coarsely ground bentonite at a water ratio of 17 %. The compaction rate was high and performed with lubricated form and stepwise loading. Tests, in order to find a technique for producing larger blocks with a diameter of the same size as a deposition hole (about 1.65 m), were also made. The technique was developed in a smaller scale (250 mm). Ring-shaped blocks with the same outer diameter and with an inner diameter of about 156 mm were also compacted. The compaction was made with vacuum in the form. The outer surface of the form was conical and most of the tests were performed with a lubricated form. Tests were performed with different water ratios of the bentonite. All the blocks had a good quality. In consequence of the good test results a form with a 1000 mm diameter was constructed and a number of compaction tests were performed. The same technique was used as for the smaller blocks. The compaction pressure in most tests was 100 MPa (maximum compaction load 80.000 kN). The tests were performed at HYDROWELD in Ystad in a press with a maximum capacity of 300.000 kN. All tests were performed with MX-80. Most of the blocks had a good quality. A small damage close to the upper surface of all blocks was observed but is considered to be of no importance for the possibility to handle the blocks and is not affecting the properties

  1. 21 CFR 177.1810 - Styrene block polymers.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Styrene block polymers. 177.1810 Section 177.1810... FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use as Basic Components of Single and Repeated Use Food Contact Surfaces § 177.1810 Styrene block polymers. The styrene...

  2. Synthesis and characterization of ferrocene containing block copolymers

    DEFF Research Database (Denmark)

    Chernyy, Sergey; Wang, Zhongli; Kirkensgaard, Jacob Judas Kain

    2017-01-01

    Narrowly dispersed diblock copolymers containing poly(methyl methacrylate) [PMMA] or poly(nonafluorohexyl methacrylate) [PF9MA] as the first block and poly(ferrocenylmethyl methacrylate) [PFMMA] as the second block, were prepared by anionic polymerization for the first time. Disordered bulk morph...... of the solvent and without the need for preliminary surface modification, for example by means of grafted brush layer....

  3. SUPERFICIAL CERVICAL PLEXUS BLOCK

    Directory of Open Access Journals (Sweden)

    Komang Mega Puspadisari

    2014-01-01

    Full Text Available Superficial cervical plexus block is one of the regional anesthesia in  neck were limited to thesuperficial fascia. Anesthesia is used to relieve pain caused either during or after the surgery iscompleted. This technique can be done by landmark or with ultrasound guiding. The midpointof posterior border of the Sternocleidomastoid was identified and the prosedure done on thatplace or on the level of cartilage cricoid.

  4. Change Around the Block?

    Science.gov (United States)

    Berlin, Joey

    2017-04-01

    Proponents of a block grant or per-capita cap trumpet them as vehicles for the federal government to give the states a capped amount of funding for Medicaid that legislatures would effectively distribute how they see fit. Questions abound as to what capped Medicaid funding would look like, and what effect it would have on the current Medicaid-eligible population, covered services, and physician payments.

  5. Managing access block.

    Science.gov (United States)

    Cameron, Peter; Scown, Paul; Campbell, Donald

    2002-01-01

    There is pessimism regarding the ability of the Acute Health Sector to manage access block for emergency and elective patients. Melbourne Health suffered an acute bed crisis in 2001 resulting in record ambulance diversions and emergency department (ED) delays. We conducted an observational study to reduce access block for emergency patients whilst maintaining elective throughput at Melbourne Health. This involved a clinician-led taskforce using previously proven principles for organisational change to implement 51 actions to improve patient access over a three-month period. The primary outcome measures were ambulance diversion, emergency patients waiting more than 12 hours for an inpatient bed, elective throughput and theatre cancellations. Despite a reduction in multi-day bed numbers all primary objectives were met, ambulance diversion decreased to minimal levels, 12-hour waits decreased by 40% and elective throughput was maintained. Theatre cancellations were also minimised. We conclude that access block can be improved by clinician-led implementation of proven process improvements over a short time frame. The ability to sustain change over the longer term requires further study.

  6. Beam manipulating by metallic nano-slits with variant widths.

    Science.gov (United States)

    Shi, Haofei; Wang, Changtao; Du, Chunlei; Luo, Xiangang; Dong, Xiaochun; Gao, Hongtao

    2005-09-05

    A novel method is proposed to manipulate beam by modulating light phase through a metallic film with arrayed nano-slits, which have constant depth but variant widths. The slits transport electro-magnetic energy in the form of surface plasmon polaritons (SPPs) in nanometric waveguides and provide desired phase retardations of beam manipulating with variant phase propagation constant. Numerical simulation of an illustrative lens design example is performed through finite-difference time-domain (FDTD) method and shows agreement with theory analysis result. In addition, extraordinary optical transmission of SPPs through sub-wavelength metallic slits is observed in the simulation and helps to improve elements' energy using factor.

  7. The crystal structure of a coxsackievirus B3-RD variant and a refined 9-angstrom cryo-electron microscopy reconstruction of the virus complexed with decay-accelerating factor (DAF) provide a new footprint of DAF on the virus surface.

    Science.gov (United States)

    Yoder, Joshua D; Cifuente, Javier O; Pan, Jieyan; Bergelson, Jeffrey M; Hafenstein, Susan

    2012-12-01

    The coxsackievirus-adenovirus receptor (CAR) and decay-accelerating factor (DAF) have been identified as cellular receptors for coxsackievirus B3 (CVB3). The first described DAF-binding isolate was obtained during passage of the prototype strain, Nancy, on rhabdomyosarcoma (RD) cells, which express DAF but very little CAR. Here, the structure of the resulting variant, CVB3-RD, has been solved by X-ray crystallography to 2.74 Å, and a cryo-electron microscopy reconstruction of CVB3-RD complexed with DAF has been refined to 9.0 Å. This new high-resolution structure permits us to correct an error in our previous view of DAF-virus interactions, providing a new footprint of DAF that bridges two adjacent protomers. The contact sites between the virus and DAF clearly encompass CVB3-RD residues recently shown to be required for binding to DAF; these residues interact with DAF short consensus repeat 2 (SCR2), which is known to be essential for virus binding. Based on the new structure, the mode of the DAF interaction with CVB3 differs significantly from the mode reported previously for DAF binding to echoviruses.

  8. Concrete blocks' adverse effects on indoor air and recommended solutions

    International Nuclear Information System (INIS)

    Ruppersberger, J.S.

    1995-01-01

    Air infiltration through highly permeable concrete blocks can allow entry of various serious indoor air pollutants including radon. An easy approach to avoiding these pollutants is to select a less-air-permeable concrete block. Tests show that air permeability of concrete blocks can vary by a factor greater than 50 (0.63--35 standard L/min/m 2 at 3 Pa). The surface texture of the blocks correlates well with air permeability; test results of smoother, closed-surface-texture blocks were usually less air-permeable. During construction, air infiltration can be minimized by capping walls and carefully sealing around openings for utilities or other penetrations. Structures with indoor air-quality problems due to soil-gas entry can be mitigated more effectively with less coating material if the blocks have a closed surface texture. All coatings evaluated--cementaceous block filler (which has the lowest applied cost and is more than 99.5% effective), surface bonding cement, water-based epoxy, polysulfide vinyl acrylic, and latex (three coats)--were highly effective (more than 98%) in reducing air permeability when adequately applied. Coating selection should be influenced by expected service life, considering surface condition and cost

  9. Data-variant kernel analysis

    CERN Document Server

    Motai, Yuichi

    2015-01-01

    Describes and discusses the variants of kernel analysis methods for data types that have been intensely studied in recent years This book covers kernel analysis topics ranging from the fundamental theory of kernel functions to its applications. The book surveys the current status, popular trends, and developments in kernel analysis studies. The author discusses multiple kernel learning algorithms and how to choose the appropriate kernels during the learning phase. Data-Variant Kernel Analysis is a new pattern analysis framework for different types of data configurations. The chapters include

  10. Nutritionally Variant Streptococci Interfere with Streptococcus mutans Adhesion Properties and Biofilm Formation.

    Science.gov (United States)

    Angius, Fabrizio; Madeddu, Maria Antonietta; Pompei, Raffaello

    2015-04-01

    The bacterial species Streptococcus mutans is known as the main cause of dental caries in humans. Therefore, much effort has focused on preventing oral colonization by this strain or clearing it from oral tissues. The oral cavity is colonized by several bacterial species that constitute the commensal oral flora, but none of these is able to interfere with the cariogenic properties of S. mutans. This paper describes the interfering ability of some nutritionally variant streptococcal strains (NVS) with S. mutans adhesion to glass surfaces and also to hydroxylapatite. In mixed cultures, NVS induce a complete inhibition of S. mutans microcolony formation on cover glass slides. NVS can also block the adherence of radiolabeled S. mutans to hydroxylapatite in the presence of both saliva and sucrose. The analysis of the action mechanism of NVS demonstrated that NVS are more hydrophobic than S. mutans and adhere tightly to hard surfaces. In addition, a cell-free culture filtrate of NVS was also able to interfere with S. mutans adhesion to hydroxylapatite. Since NVS are known to secrete some important bacteriolytic enzymes, we conclude that NVS can be a natural antagonist to the cariogenic properties of S. mutans.

  11. Development of Deflection Prediction Model for Concrete Block Pavement Considering the Block Shapes and Construction Patterns

    Directory of Open Access Journals (Sweden)

    Wuguang Lin

    2016-01-01

    Full Text Available Concrete block pavement (CBP is distinct from typical concrete or asphalt pavements. It is built by using individual blocks with unique construction patterns forming a discrete surface layer to bear traffic loadings. The surface structure of CBP varies depending on the block shapes and construction patterns, so it is hard to apply a general equivalent elastic modulus estimation method to define the surface structural strength. In this study, FEM analysis and dynamic loading test were carried out to develop a deflection prediction model for CBP considering the block shapes and construction patterns. Based on the analysis results, it was found that block shapes did not have much effect on load distribution, whereas construction patterns did. By applying the deflection prediction model to the rutting model for CBP proposed by Sun, the herringbone bond pattern showed the best performance comparing with stretcher bond or basket weave bond pattern. As the load repetition increased to 1.2 million, the rutting depth of CBP constructed by herringbone bond pattern was 2 mm smaller than those constructed by the other two patterns.

  12. Comparative Study on Different Slot Forms of Prestressed Anchor Blocks

    Science.gov (United States)

    Fan, Rong; Si, Jianhui; Jian, Zheng

    2018-03-01

    In this paper, two models of prestressed pier, rectangular cavity anchor block and arch hollow anchor block are established. The ABAQUS software was used to calculate the stress of the surface of the neck of the pier and the cavity of the anchor block, through comparative analysis. The results show that compared with the rectangular cavity anchor block, the stress of the pier and the cavity can be effectively reduced when the arch hole is used, and the amount of prestressed anchor can be reduced, so as to obtain obvious economic benefits.

  13. Turbulence Interface Simulation by Lagrangian Blocks

    Science.gov (United States)

    Chu, V. H.

    2015-12-01

    Most computational fluid-dynamics codes are developed using the Eulerian description. To find the numerical solution, fluxes are estimated on the surface of the finite volume using a truncation series. Spurious numerical oscillations and artificial numerical diffusion are consequences, particularly in regions across flow discontinuities. Diffusion often is introduced synthetically in many schemes to gain computational stability. Occasional switching to a diffusive upwind scheme, for example, is one classic strategy to manage the numerical oscillations [see e.g., Ghannadi & Chu 2015]. Lagrangian-block simulation offers an alternative that could minimize the spurious oscillations and false diffusive error. The blocks move in the direction of the flow. The squares of the block widths expand in proportion to the diffusivities. The block simulation procedure consists of (i) Lagrangian advection and diffusion, (ii) division into portions, and (iii) reassembly of the portions into new blocks. The blocks are renewed in each time increment to prevent excessive distortion. Details of the Lagrangian-block simulations method have been given in a series of papers by Tan & Chu (2012), Chu & Altai (2012, 2015}. In this paper, the exchanges across turbulence interfaces are considered for two problems. The first series of the simulations are conducted to find the mass and momentum exchanges across a shallow flow of two different depth. In the simulations, the advection and diffusion of three separated systems of blocks that contain the mass, momentum and potential vorticity are carried out using the Lagrangian-block simulation method. The simulation results are compared with data obtained from a previous laboratory investigation and related to the shear instability problem in rotating shear flow previously considered by Chu (2014). The second problem involves the turbulence generation across the interface of an internal waves. The simulation shows the development of gravitational

  14. Paving block study : final report.

    Science.gov (United States)

    1971-10-01

    The Louisiana Department of Highways has conducted field tests with an experimental revetment consisting of cellular concrete revetment blocks used in conjunction with plastic filter cloth and/or vegetation such as grass or vines. The precast blocks ...

  15. Habitat Blocks and Wildlife Corridors

    Data.gov (United States)

    Vermont Center for Geographic Information — Habitat blocks are areas of contiguous forest and other natural habitats that are unfragmented by roads, development, or agriculture. Vermonts habitat blocks are...

  16. Demographic Data - MDC_Block

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — A polygon feature class of Miami-Dade Census 2000 Blocks. Census blocks are areas bounded on all sides by visible and/or invisible features shown on a map prepared...

  17. Modeling disease risk through analysis of physical interactions between genetic variants within chromatin regulatory circuitry.

    Science.gov (United States)

    Corradin, Olivia; Cohen, Andrea J; Luppino, Jennifer M; Bayles, Ian M; Schumacher, Fredrick R; Scacheri, Peter C

    2016-11-01

    SNPs associated with disease susceptibility often reside in enhancer clusters, or super-enhancers. Constituents of these enhancer clusters cooperate to regulate target genes and often extend beyond the linkage disequilibrium (LD) blocks containing risk SNPs identified in genome-wide association studies (GWAS). We identified 'outside variants', defined as SNPs in weak LD with GWAS risk SNPs that physically interact with risk SNPs as part of a target gene's regulatory circuitry. These outside variants further explain variation in target gene expression beyond that explained by GWAS-associated SNPs. Additionally, the clinical risk associated with GWAS SNPs is considerably modified by the genotype of outside variants. Collectively, these findings suggest a potential model in which outside variants and GWAS SNPs that physically interact in 3D chromatin collude to influence target transcript levels as well as clinical risk. This model offers an additional hypothesis for the source of missing heritability for complex traits.

  18. GCPII Variants, Paralogs and Orthologs

    Czech Academy of Sciences Publication Activity Database

    Hlouchová, Klára; Navrátil, Václav; Tykvart, Jan; Šácha, Pavel; Konvalinka, Jan

    2012-01-01

    Roč. 19, č. 9 (2012), s. 1316-1322 ISSN 0929-8673 R&D Projects: GA ČR GAP304/12/0847 Institutional research plan: CEZ:AV0Z40550506 Keywords : PSMA * GCPIII * NAALADase L * splice variants * homologs * PSMAL Subject RIV: CE - Biochemistry Impact factor: 4.070, year: 2012

  19. Blocking the Hawking radiation

    DEFF Research Database (Denmark)

    Autzen, M.; Kouvaris, C.

    2014-01-01

    grows after its formation (and eventually destroys the star) instead of evaporating. The fate of the black hole is dictated by the two opposite mechanics, i.e., accretion of nuclear matter from the center of the star and Hawking radiation that tends to decrease the mass of the black hole. We study how...... the assumptions for the accretion rate can in fact affect the critical mass beyond which a black hole always grows. We also study to what extent degenerate nuclear matter can impede Hawking radiation due to the fact that emitted particles can be Pauli blocked at the core of the star....

  20. How Artists Overcome Creative Blocks.

    Science.gov (United States)

    Hirst, Barbara

    1992-01-01

    Six practicing artists were interviewed about how they overcome creative blocks. Their responses indicated that feelings of self-doubt, fear, and depression accompany blocks but that relaxing and working on new directions and playing ideas off a supportive person helped to overcome such blocks. (DB)

  1. Block Scheduling in High Schools.

    Science.gov (United States)

    Irmsher, Karen

    1996-01-01

    Block Scheduling has been considered a cure for a lengthy list of educational problems. This report reviews the literature on block schedules and describes some Oregon high schools that have integrated block scheduling. Major disadvantages included resistance to change and requirements that teachers change their teaching strategies. There is…

  2. Abdominal wall blocks in adults

    DEFF Research Database (Denmark)

    Neimann, Jens Dupont Børglum; Gögenür, Ismail; Bendtsen, Thomas F.

    2016-01-01

    Purpose of review Abdominal wall blocks in adults have evolved much during the last decade; that is, particularly with the introduction of ultrasound-guided (USG) blocks. This review highlights recent advances of block techniques within this field and proposes directions for future research.  Rec...

  3. Method of forming oriented block copolymer line patterns, block copolymer line patterns formed thereby, and their use to form patterned articles

    Energy Technology Data Exchange (ETDEWEB)

    Russell, Thomas P.; Hong, Sung Woo; Lee, Dong Hyun; Park, Soojin; Xu, Ting

    2017-08-01

    A block copolymer film having a line pattern with a high degree of long-range order is formed by a method that includes forming a block copolymer film on a substrate surface with parallel facets, and annealing the block copolymer film to form an annealed block copolymer film having linear microdomains parallel to the substrate surface and orthogonal to the parallel facets of the substrate. The line-patterned block copolymer films are useful for the fabrication of magnetic storage media, polarizing devices, and arrays of nanowires.

  4. Program structure-based blocking

    Science.gov (United States)

    Bertolli, Carlo; Eichenberger, Alexandre E.; O'Brien, John K.; Sura, Zehra N.

    2017-09-26

    Embodiments relate to program structure-based blocking. An aspect includes receiving source code corresponding to a computer program by a compiler of a computer system. Another aspect includes determining a prefetching section in the source code by a marking module of the compiler. Yet another aspect includes performing, by a blocking module of the compiler, blocking of instructions located in the prefetching section into instruction blocks, such that the instruction blocks of the prefetching section only contain instructions that are located in the prefetching section.

  5. Swine Influenza/Variant Influenza Viruses

    Science.gov (United States)

    ... Humans Key Facts about Human Infections with Variant Viruses Interim Guidance for Clinicians on Human Infections Background, Risk Assessment & Reporting Reported Infections with Variant Influenza Viruses in the United States since 2005 Past Outbreaks ...

  6. Clinical Implications of HIV-1 Minority Variants

    OpenAIRE

    Li, Jonathan Z.; Kuritzkes, Daniel R.

    2013-01-01

    Low-frequency HIV variants are increasingly recognized as a key factor that increases the risk of HIV treatment failure. This article will provide a review of HIV minority variants, including their demonstrated clinical impact and areas of controversy.

  7. From phantom blocks to denudational noise

    OpenAIRE

    Munack, Henry (Dr)

    2015-01-01

    Knowing the rates and mechanisms of geomorphic process that shape the Earth’s surface is crucial to understand landscape evolution. Modern methods for estimating denudation rates enable us to quantitatively express and compare processes of landscape downwearing that can be traced through time and space—from the seemingly intact, though intensely shattered, phantom blocks of the catastrophically fragmented basal facies of giant rockslides up to denudational noise in orogen-wide data sets avera...

  8. Antigen Loss Variants: Catching Hold of Escaping Foes.

    Science.gov (United States)

    Vyas, Maulik; Müller, Rolf; Pogge von Strandmann, Elke

    2017-01-01

    Since mid-1990s, the field of cancer immunotherapy has seen steady growth and selected immunotherapies are now a routine and preferred therapeutic option of certain malignancies. Both active and passive cancer immunotherapies exploit the fact that tumor cells express specific antigens on the cell surface, thereby mounting an immune response specifically against malignant cells. It is well established that cancer cells typically lose surface antigens following natural or therapy-induced selective pressure and these antigen-loss variants are often the population that causes therapy-resistant relapse. CD19 and CD20 antigen loss in acute lymphocytic leukemia and chronic lymphocytic leukemia, respectively, and lineage switching in leukemia associated with mixed lineage leukemia (MLL) gene rearrangements are well-documented evidences in this regard. Although increasing number of novel immunotherapies are being developed, majority of these do not address the control of antigen loss variants. Here, we review the occurrence of antigen loss variants in leukemia and discuss the therapeutic strategies to tackle the same. We also present an approach of dual-targeting immunoligand effectively retargeting NK cells against antigen loss variants in MLL-associated leukemia. Novel immunotherapies simultaneously targeting more than one tumor antigen certainly hold promise to completely eradicate tumor and prevent therapy-resistant relapses.

  9. Time-variant reliability assessment through equivalent stochastic process transformation

    International Nuclear Information System (INIS)

    Wang, Zequn; Chen, Wei

    2016-01-01

    Time-variant reliability measures the probability that an engineering system successfully performs intended functions over a certain period of time under various sources of uncertainty. In practice, it is computationally prohibitive to propagate uncertainty in time-variant reliability assessment based on expensive or complex numerical models. This paper presents an equivalent stochastic process transformation approach for cost-effective prediction of reliability deterioration over the life cycle of an engineering system. To reduce the high dimensionality, a time-independent reliability model is developed by translating random processes and time parameters into random parameters in order to equivalently cover all potential failures that may occur during the time interval of interest. With the time-independent reliability model, an instantaneous failure surface is attained by using a Kriging-based surrogate model to identify all potential failure events. To enhance the efficacy of failure surface identification, a maximum confidence enhancement method is utilized to update the Kriging model sequentially. Then, the time-variant reliability is approximated using Monte Carlo simulations of the Kriging model where system failures over a time interval are predicted by the instantaneous failure surface. The results of two case studies demonstrate that the proposed approach is able to accurately predict the time evolution of system reliability while requiring much less computational efforts compared with the existing analytical approach. - Highlights: • Developed a new approach for time-variant reliability analysis. • Proposed a novel stochastic process transformation procedure to reduce the dimensionality. • Employed Kriging models with confidence-based adaptive sampling scheme to enhance computational efficiency. • The approach is effective for handling random process in time-variant reliability analysis. • Two case studies are used to demonstrate the efficacy

  10. Variant Humicola grisea CBH1.1

    Energy Technology Data Exchange (ETDEWEB)

    Goedegebuur, Frits; Gualfetti, Peter; Mitchinson, Colin; Larenas, Edmund

    2017-05-09

    Disclosed are variants of Humicola grisea CeI7A (CBH1.1), H. jecorina CBH1 variant or S. thermophilium CBH1, nucleic acids encoding the same and methods for producing the same. The variant cellulases have the amino acid sequence of a glycosyl hydrolase of family 7A wherein one or more amino acid residues are substituted.

  11. Celiac ganglia block

    Energy Technology Data Exchange (ETDEWEB)

    Akinci, Devrim [Department of Radiology, Hacettepe University School of Medicine, Sihhiye, 06100 Ankara (Turkey); Akhan, Okan [Department of Radiology, Hacettepe University School of Medicine, Sihhiye, 06100 Ankara (Turkey)]. E-mail: oakhan@hacettepe.edu.tr

    2005-09-01

    Pain occurs frequently in patients with advanced cancers. Tumors originating from upper abdominal viscera such as pancreas, stomach, duodenum, proximal small bowel, liver and biliary tract and from compressing enlarged lymph nodes can cause severe abdominal pain, which do not respond satisfactorily to medical treatment or radiotherapy. Percutaneous celiac ganglia block (CGB) can be performed with high success and low complication rates under imaging guidance to obtain pain relief in patients with upper abdominal malignancies. A significant relationship between pain relief and degree of tumoral celiac ganglia invasion according to CT features was described in the literature. Performing the procedure in the early grades of celiac ganglia invasion on CT can increase the effectiveness of the CGB, which is contrary to World Health Organization criteria stating that CGB must be performed in patients with advanced stage cancer. CGB may also be effectively performed in patients with chronic pancreatitis for pain palliation.

  12. Photovoltaic building blocks

    DEFF Research Database (Denmark)

    Hanberg, Peter Jesper; Jørgensen, Anders Michael

    2014-01-01

    efficiency of about 15% for commercial Silicon solar cells there is still much to gain. DTU Danchip provides research facilities, equipment and expertise for the building blocks that comprises fabricating the efficient solar cell. In order to get more of the sun light into the device we provide thin film......Photovoltaics (PV), better known as solar cells, are now a common day sight on many rooftops in Denmark.The installed capacity of PV systems worldwide is growing exponentially1 and is the third most importantrenewable energy source today. The cost of PV is decreasing fast with ~10%/year but to make...... it directcompetitive with fossil energy sources a further reduction is needed. By increasing the efficiency of the solar cells one gain an advantage through the whole chain of cost. So that per produced Watt of power less material is spent, installation costs are lower, less area is used etc. With an average...

  13. Atomic Basic Blocks

    Science.gov (United States)

    Scheler, Fabian; Mitzlaff, Martin; Schröder-Preikschat, Wolfgang

    Die Entscheidung, einen zeit- bzw. ereignisgesteuerten Ansatz für ein Echtzeitsystem zu verwenden, ist schwierig und sehr weitreichend. Weitreichend vor allem deshalb, weil diese beiden Ansätze mit äußerst unterschiedlichen Kontrollflussabstraktionen verknüpft sind, die eine spätere Migration zum anderen Paradigma sehr schwer oder gar unmöglich machen. Wir schlagen daher die Verwendung einer Zwischendarstellung vor, die unabhängig von der jeweils verwendeten Kontrollflussabstraktion ist. Für diesen Zweck verwenden wir auf Basisblöcken basierende Atomic Basic Blocks (ABB) und bauen darauf ein Werkzeug, den Real-Time Systems Compiler (RTSC) auf, der die Migration zwischen zeit- und ereignisgesteuerten Systemen unterstützt.

  14. Celiac ganglia block

    International Nuclear Information System (INIS)

    Akinci, Devrim; Akhan, Okan

    2005-01-01

    Pain occurs frequently in patients with advanced cancers. Tumors originating from upper abdominal viscera such as pancreas, stomach, duodenum, proximal small bowel, liver and biliary tract and from compressing enlarged lymph nodes can cause severe abdominal pain, which do not respond satisfactorily to medical treatment or radiotherapy. Percutaneous celiac ganglia block (CGB) can be performed with high success and low complication rates under imaging guidance to obtain pain relief in patients with upper abdominal malignancies. A significant relationship between pain relief and degree of tumoral celiac ganglia invasion according to CT features was described in the literature. Performing the procedure in the early grades of celiac ganglia invasion on CT can increase the effectiveness of the CGB, which is contrary to World Health Organization criteria stating that CGB must be performed in patients with advanced stage cancer. CGB may also be effectively performed in patients with chronic pancreatitis for pain palliation

  15. Clinicopathologic Variants of Mycosis Fungoides.

    Science.gov (United States)

    Muñoz-González, H; Molina-Ruiz, A M; Requena, L

    2017-04-01

    Mycosis fungoides (MF) is the most common primary cutaneous T-cell lymphoma. The clinical course of the disease is typically characterized by progression from a nonspecific phase of erythematous macules to the appearance of plaques and ultimately, in some patients, tumors. However, numerous clinical and histopathologic variants of MF with specific therapeutic and prognostic implications have been described in recent decades. Clarification of the differential diagnosis can be frustrated by the wide range of clinical manifestations and histopathologic patterns of cutaneous infiltration, particularly in the early phases of the disease. In this paper, we review the main clinical, histopathologic, and immunohistochemical characteristics of the variants of MF described in the literature in order to facilitate early diagnosis of the disease. Copyright © 2016 AEDV. Publicado por Elsevier España, S.L.U. All rights reserved.

  16. Linear analysis of rotationally invariant, radially variant tomographic imaging systems

    International Nuclear Information System (INIS)

    Huesmann, R.H.

    1990-01-01

    This paper describes a method to analyze the linear imaging characteristics of rotationally invariant, radially variant tomographic imaging systems using singular value decomposition (SVD). When the projection measurements from such a system are assumed to be samples from independent and identically distributed multi-normal random variables, the best estimate of the emission intensity is given by the unweighted least squares estimator. The noise amplification of this estimator is inversely proportional to the singular values of the normal matrix used to model projection and backprojection. After choosing an acceptable noise amplification, the new method can determine the number of parameters and hence the number of pixels that should be estimated from data acquired from an existing system with a fixed number of angles and projection bins. Conversely, for the design of a new system, the number of angles and projection bins necessary for a given number of pixels and noise amplification can be determined. In general, computing the SVD of the projection normal matrix has cubic computational complexity. However, the projection normal matrix for this class of rotationally invariant, radially variant systems has a block circulant form. A fast parallel algorithm to compute the SVD of this block circulant matrix makes the singular value analysis practical by asymptotically reducing the computation complexity of the method by a multiplicative factor equal to the number of angles squared

  17. Chaotic Mountain Blocks in Pluto’s Sputnik Planitia

    Science.gov (United States)

    Singer, Kelsi N.; Knight, Katherine I.; Stern, S. Alan; Olkin, Catherine; Grundy, William M.; McKinnon, William B.; Moore, Jeffrey M.; Schenk, Paul M.; Spencer, John R.; Weaver, Harold A.; Young, Leslie; Ennico, Kimberly; New Horizons Geology, Geophysics and Imaging Science Theme Team, The New Horizons Surface Composition Science Theme Team

    2017-10-01

    One of the first high-resolution Pluto images returned by New Horizons displayed a collection of tall, jagged peaks rising out of the large nitrogen ice sheet informally known as Sputnik Planitia (SP). This mountain range was later revealed to be one of several along the western edge of SP. The mountains are several hundred broken-up blocks of Pluto’s primarily water ice lithosphere and some retain surface terrains similar to the nearby intact crust surrounding SP. Water ice with some fractures or porosity is likely >5% less dense than solid N2 ice at Pluto’s temperatures. Thus it is possible the blocks are, or were, floating icebergs or at least partially suspended to the point that some blocks appear to be tilted as if they have faltered (Moore et al., 2016, Science, 351, 1284-1293).We analyze four mountain ranges on the western edge of SP and compare to chaotic terrains on Europa and Mars. The blocks on Pluto have angular planforms but we characterize their size using block surface area converted to an equivalent circular diameter. Topography was used to define block extents. The blocks range in size from 3-30 km in diameter, with a mode of ~8-10 km. Blocks range from 0.2-3.8 km in height, and block height generally increases with block diameter. One or more dark layers can be identified in a few scarp faces, and are at a similar depth to each other and to layers seen in fault and crater walls elsewhere on Pluto. A large N-S trending fault system runs tangential to SP and may be the source of crustal disruption on the western side.On Europa and Mars block sizes vary greatly between different chaos regions, but Conamara Chaos has an average block size of ~5 km in diameter, smaller than that typically seen on Pluto. Also the blocks often transition into fractured terrain still connected to the surround lithosphere at the periphery of the chaos regions. The source regions for the blocks are more obvious on Europa and Mars. Additionally the block heights on

  18. Microcystic Variant of Urothelial Carcinoma

    Directory of Open Access Journals (Sweden)

    Anthony Kodzo-Grey Venyo

    2013-01-01

    Full Text Available Background. Microcystic variant of urothelial carcinoma is one of the new variants of urothelial carcinoma that was added to the WHO classification in 2004. Aims. To review the literature on microcystic variant of urothelial carcinoma. Methods. Various internet search engines were used to identify reported cases of the tumour. Results. Microscopic features of the tumour include: (i Conspicuous intracellular and intercellular lumina/microcysts encompassed by malignant urothelial or squamous cells. (ii The lumina are usually empty; may contain granular eosinophilic debris, mucin, or necrotic cells. (iii The cysts may be variable in size; round, or oval, up to 2 mm; lined by urothelium which are either flattened cells or low columnar cells however, they do not contain colonic epithelium or goblet cells; are infiltrative; invade the muscularis propria; mimic cystitis cystica and cystitis glandularis; occasionally exhibit neuroendocrine differentiation. (iv Elongated and irregular branching spaces are usually seen. About 17 cases of the tumour have been reported with only 2 patients who have survived. The tumour tends to be of high-grade and high-stage. There is no consensus opinion on the best option of treatment of the tumour. Conclusions. It would prove difficult at the moment to be dogmatic regarding its prognosis but it is a highly aggressive tumour. New cases of the tumour should be reported in order to document its biological behaviour.

  19. Patchy micelles based on coassembly of block copolymer chains and block copolymer brushes on silica particles.

    Science.gov (United States)

    Zhu, Shuzhe; Li, Zhan-Wei; Zhao, Hanying

    2015-04-14

    Patchy particles are a type of colloidal particles with one or more well-defined patches on the surfaces. The patchy particles with multiple compositions and functionalities have found wide applications from the fundamental studies to practical uses. In this research patchy micelles with thiol groups in the patches were prepared based on coassembly of free block copolymer chains and block copolymer brushes on silica particles. Thiol-terminated and cyanoisopropyl-capped polystyrene-block-poly(N-isopropylacrylamide) block copolymers (PS-b-PNIPAM-SH and PS-b-PNIPAM-CIP) were synthesized by reversible addition-fragmentation chain transfer polymerization and chemical modifications. Pyridyl disulfide-functionalized silica particles (SiO2-SS-Py) were prepared by four-step surface chemical reactions. PS-b-PNIPAM brushes on silica particles were prepared by thiol-disulfide exchange reaction between PS-b-PNIPAM-SH and SiO2-SS-Py. Surface micelles on silica particles were prepared by coassembly of PS-b-PNIPAM-CIP and block copolymer brushes. Upon cleavage of the surface micelles from silica particles, patchy micelles with thiol groups in the patches were obtained. Dynamic light scattering, transmission electron microscopy, and zeta-potential measurements demonstrate the preparation of patchy micelles. Gold nanoparticles can be anchored onto the patchy micelles through S-Au bonds, and asymmetric hybrid structures are formed. The thiol groups can be oxidized to disulfides, which results in directional assembly of the patchy micelles. The self-assembly behavior of the patchy micelles was studied experimentally and by computer simulation.

  20. CAMELOT: A machine learning approach for coarse-grained simulations of aggregation of block-copolymeric protein sequences

    Energy Technology Data Exchange (ETDEWEB)

    Ruff, Kiersten M. [Computational and Systems Biology Program and Center for Biological Systems Engineering, Washington University in St. Louis, St. Louis, Missouri 63130-4899 (United States); Harmon, Tyler S. [Department of Physics and Center for Biological Systems Engineering, Washington University in St. Louis, St. Louis, Missouri 63130-4899 (United States); Pappu, Rohit V., E-mail: pappu@wustl.edu [Department of Biomedical Engineering and Center for Biological Systems Engineering, Washington University in St. Louis, CB 1097, St. Louis, Missouri 63130-4899 (United States)

    2015-12-28

    We report the development and deployment of a coarse-graining method that is well suited for computer simulations of aggregation and phase separation of protein sequences with block-copolymeric architectures. Our algorithm, named CAMELOT for Coarse-grained simulations Aided by MachinE Learning Optimization and Training, leverages information from converged all atom simulations that is used to determine a suitable resolution and parameterize the coarse-grained model. To parameterize a system-specific coarse-grained model, we use a combination of Boltzmann inversion, non-linear regression, and a Gaussian process Bayesian optimization approach. The accuracy of the coarse-grained model is demonstrated through direct comparisons to results from all atom simulations. We demonstrate the utility of our coarse-graining approach using the block-copolymeric sequence from the exon 1 encoded sequence of the huntingtin protein. This sequence comprises of 17 residues from the N-terminal end of huntingtin (N17) followed by a polyglutamine (polyQ) tract. Simulations based on the CAMELOT approach are used to show that the adsorption and unfolding of the wild type N17 and its sequence variants on the surface of polyQ tracts engender a patchy colloid like architecture that promotes the formation of linear aggregates. These results provide a plausible explanation for experimental observations, which show that N17 accelerates the formation of linear aggregates in block-copolymeric N17-polyQ sequences. The CAMELOT approach is versatile and is generalizable for simulating the aggregation and phase behavior of a range of block-copolymeric protein sequences.

  1. Dimensional reduction for conformal blocks

    Science.gov (United States)

    Hogervorst, Matthijs

    2016-09-01

    We consider the dimensional reduction of a CFT, breaking multiplets of the d-dimensional conformal group SO( d + 1 , 1) up into multiplets of SO( d, 1). This leads to an expansion of d-dimensional conformal blocks in terms of blocks in d - 1 dimensions. In particular, we obtain a formula for 3 d conformal blocks as an infinite sum over 2 F 1 hypergeometric functions with closed-form coefficients.

  2. Learning Potentials in Number Blocks

    DEFF Research Database (Denmark)

    Majgaard, Gunver; Misfeldt, Morten; Nielsen, Jacob

    2012-01-01

    . The tool is called Number Blocks and it combines physical interaction, learning, and immediate feedback. Number Blocks supports the children's understanding of place value in the sense that it allows them to experiment with creating large numbers. We found the blocks contributed to the learning process...... in several ways. The blocks combined mathematics and play, and they included and supported children at different academic levels. The auditory representation, especially the enhanced rhythmic effects due to using speech synthesis, and the rhythm helped the children to pronounce large numbers. This creates...

  3. Common blocks for ASQS(12

    Directory of Open Access Journals (Sweden)

    Lorenzo Milazzo

    1997-05-01

    Full Text Available An ASQS(v is a particular Steiner system featuring a set of v vertices and two separate families of blocks, B and G, whose elements have a respective cardinality of 4 and 6. It has the property that any three vertices of X belong either to a B-block or to a G-block. The parameter cb is the number of common blocks in two separate ASQSs, both defined on the same set of vertices X . In this paper it is shown that cb ≤ 29 for any pair of ASQSs(12.

  4. 31 CFR 545.301 - Blocked account; blocked property.

    Science.gov (United States)

    2010-07-01

    ... (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY TALIBAN (AFGHANISTAN) SANCTIONS... name of the Taliban or persons whose property or interests in property are blocked pursuant to § 545.201, or in which the Taliban or persons whose property or interests in property are blocked pursuant...

  5. Following of erosive wash of soil in variants with different intercrops

    Directory of Open Access Journals (Sweden)

    Barbora Badalíková

    2010-01-01

    Full Text Available In a pilot experiment established in a sugar beet growing region the erosive washing away of soil was studied in the years 2006 to 2008. The area is located at an altitude of 246 m with the long-term mean precipitation of 500 mm and the mean annual temperature of 8.4 °C. The soils are classified as Chernozem, moderately heavy, loamy, with a good supply of nutrients, humus content of 2.30 % and an alkaline soil reaction. Slope gradient is 12 %, exposition is NE. To study the role of intercrops in erosion control, three variants were established after the harvest of the main crop, two variants with different intercrops and one (control with no intercrop. These were Variant 1 with Secale cereale L. var. multicaule METZG. ex ALEF., a non-freezing intercrop, Variant 2 with cluster mallow (Malva verticillata L., a freezing intercrop, and a control variant with no intercrop. In Variant 1 Secale cereale L. var. multicaule was desiccated with the herbicide Roundup in early spring. All the variants involved maize as the main crop. In variants 1 and 2, maize was sown in intercrop residues after seedbed preparation by Vario and a compactor. In Variant 3 maize was sown after conventional seedbed preparation. For assessment of soil conditions soil samples were taken to determine soil physical and chemical properties and water content in the soil. Soil loss by erosion was determined using specially-designed pockets. Erosive washing away of soil was monitored during the entire growing season of maize. The variants in which intercrops were used were found very effective in soil erosion control. In Variant 3 (control without surface crop residues, the washing away of soil was recorded with each heavy torrential rain. During the all years the total amount of soil loss by erosion in this treatment was 2.25 t . ha−1.

  6. Localized structural frustration for evaluating the impact of sequence variants.

    Science.gov (United States)

    Kumar, Sushant; Clarke, Declan; Gerstein, Mark

    2016-12-01

    Population-scale sequencing is increasingly uncovering large numbers of rare single-nucleotide variants (SNVs) in coding regions of the genome. The rarity of these variants makes it challenging to evaluate their deleteriousness with conventional phenotype-genotype associations. Protein structures provide a way of addressing this challenge. Previous efforts have focused on globally quantifying the impact of SNVs on protein stability. However, local perturbations may severely impact protein functionality without strongly disrupting global stability (e.g. in relation to catalysis or allostery). Here, we describe a workflow in which localized frustration, quantifying unfavorable local interactions, is employed as a metric to investigate such effects. Using this workflow on the Protein Databank, we find that frustration produces many immediately intuitive results: for instance, disease-related SNVs create stronger changes in localized frustration than non-disease related variants, and rare SNVs tend to disrupt local interactions to a larger extent than common variants. Less obviously, we observe that somatic SNVs associated with oncogenes and tumor suppressor genes (TSGs) induce very different changes in frustration. In particular, those associated with TSGs change the frustration more in the core than the surface (by introducing loss-of-function events), whereas those associated with oncogenes manifest the opposite pattern, creating gain-of-function events. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  7. Localized structural frustration for evaluating the impact of sequence variants

    Science.gov (United States)

    Kumar, Sushant; Clarke, Declan; Gerstein, Mark

    2016-01-01

    Population-scale sequencing is increasingly uncovering large numbers of rare single-nucleotide variants (SNVs) in coding regions of the genome. The rarity of these variants makes it challenging to evaluate their deleteriousness with conventional phenotype–genotype associations. Protein structures provide a way of addressing this challenge. Previous efforts have focused on globally quantifying the impact of SNVs on protein stability. However, local perturbations may severely impact protein functionality without strongly disrupting global stability (e.g. in relation to catalysis or allostery). Here, we describe a workflow in which localized frustration, quantifying unfavorable local interactions, is employed as a metric to investigate such effects. Using this workflow on the Protein Databank, we find that frustration produces many immediately intuitive results: for instance, disease-related SNVs create stronger changes in localized frustration than non-disease related variants, and rare SNVs tend to disrupt local interactions to a larger extent than common variants. Less obviously, we observe that somatic SNVs associated with oncogenes and tumor suppressor genes (TSGs) induce very different changes in frustration. In particular, those associated with TSGs change the frustration more in the core than the surface (by introducing loss-of-function events), whereas those associated with oncogenes manifest the opposite pattern, creating gain-of-function events. PMID:27915290

  8. A PYY Q62P variant linked to human obesity

    Energy Technology Data Exchange (ETDEWEB)

    Ahituv, Nadav; Kavaslar, Nihan; Schackwitz, Wendy; Ustaszewska,Anna; Collier, John Michael; Hebert, Sybil; Doelle, Heather; Dent,Robert; Pennacchio, Len A.; McPherson, Ruth

    2005-06-27

    Members of the pancreatic polypeptide family and the irreceptors have been implicated in the control of food intake in rodents and humans. To investigate whether nucleotide changes in these candidate genes result in abnormal weight in humans, we sequenced the coding exons and splice sites of seven family members (NPY, PYY, PPY, NPY1R, NPY2R, NPY4R, and NPY5R) in a large cohort of extremely obese (n=379) and lean (n=378) individuals. In total we found eleven rare non-synonymous variants, four of which exhibited familial segregation, NPY1R L53P and PPY P63L with leanness and NPY2R D42G and PYY Q62P with obesity. Functional analysis of the obese variants revealed NPY2R D42G to have reduced cell surface expression, while previous cell culture based studies indicated variant PYY Q62P to have altered receptor binding selectivity and we show that it fails to reduce food intake through mouse peptide injection experiments. These results support that rare non-synonymous variants within these genes can alter susceptibility to human body mass index extremes.

  9. Classical Virasoro irregular conformal block

    Science.gov (United States)

    Rim, Chaiho; Zhang, Hong

    2015-07-01

    Virasoro irregular conformal block with arbitrary rank is obtained for the classical limit or equivalently Nekrasov-Shatashvili limit using the beta-deformed irregular matrix model (Penner-type matrix model for the irregular conformal block). The same result is derived using the generalized Mathieu equation which is equivalent to the loop equation of the irregular matrix model.

  10. Classical Virasoro irregular conformal block

    Energy Technology Data Exchange (ETDEWEB)

    Rim, Chaiho; Zhang, Hong [Department of Physics and Center for Quantum Spacetime (CQUeST), Sogang University,Seoul 121-742 (Korea, Republic of)

    2015-07-30

    Virasoro irregular conformal block with arbitrary rank is obtained for the classical limit or equivalently Nekrasov-Shatashvili limit using the beta-deformed irregular matrix model (Penner-type matrix model for the irregular conformal block). The same result is derived using the generalized Mathieu equation which is equivalent to the loop equation of the irregular matrix model.

  11. Four-block beam collimator

    CERN Document Server

    CERN PhotoLab

    1977-01-01

    The photo shows a four-block collimator installed on a control table for positioning the alignment reference marks. Designed for use with the secondary beams, the collimators operated in vacuum conditions. The blocks were made of steel and had a standard length of 1 m. The maximum aperture had a square coss-section of 144 cm2. (See Annual Report 1976.)

  12. OPAL Various Lead Glass Blocks

    CERN Document Server

    These lead glass blocks were part of a CERN detector called OPAL (one of the four experiments at the LEP particle detector). OPAL uses some 12 000 blocks of glass like this to measure particle energies in the electromagnetic calorimeter. This detector measured the energy deposited when electrons and photons were slowed down and stopped.

  13. Writing Blocks and Tacit Knowledge.

    Science.gov (United States)

    Boice, Robert

    1993-01-01

    A review of the literature on writing block looks at two kinds: inability to write in a timely, fluent fashion, and reluctance by academicians to assist others in writing. Obstacles to fluent writing are outlined, four historical trends in treating blocks are discussed, and implications are examined. (MSE)

  14. Block storage subsystem performance analysis

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    You feel that your service is slow because of the storage subsystem? But there are too many abstraction layers between your software and the raw block device for you to debug all this pile... Let's dive on the platters and check out how the block storage sees your I/Os! We can even figure out what those patterns are meaning.

  15. Multi Modal Face Recognition Using Block Based Curvelet Features

    OpenAIRE

    K, Jyothi; J, Prabhakar C.

    2014-01-01

    In this paper, we present multimodal 2D +3D face recognition method using block based curvelet features. The 3D surface of face (Depth Map) is computed from the stereo face images using stereo vision technique. The statistical measures such as mean, standard deviation, variance and entropy are extracted from each block of curvelet subband for both depth and intensity images independently.In order to compute the decision score, the KNN classifier is employed independently for both intensity an...

  16. Parametric Optimization Design of Brake Block Based on Reverse Engineering

    Directory of Open Access Journals (Sweden)

    Jin Hua-wei

    2017-01-01

    Full Text Available As one of the key part of automotive brake,the performance of brake block has a direct impact on the safety and comfort of cars. Modeling the brake block of disc brake in reverse parameterization by reverse engineering software, analyzing and optimizing the reconstructed model by CAE software. Processing the scanned point cloud by Geomagic Studio and reconstructing the CAD model of the brake block with the parametric surface function of the software, then analyzing and optimizing it by Wrokbench. The example shows that it is quick to reconstruct the CAD model of parts by using reverse parameterization method and reduce part re-design development cycle significantly.

  17. Modeling and Selection of Software Service Variants

    OpenAIRE

    Wittern, John Erik

    2015-01-01

    Providers and consumers have to deal with variants, meaning alternative instances of a service?s design, implementation, deployment, or operation, when developing or delivering software services. This work presents service feature modeling to deal with associated challenges, comprising a language to represent software service variants and a set of methods for modeling and subsequent variant selection. This work?s evaluation includes a POC implementation and two real-life use cases.

  18. Criminal Justice Systems. Block I: Law Enforcement. Block II: The Courts. Block III: Corrections. Block IV: Community Relations. Block V: Proficiency Skills. Block VI: Criminalistics. Student Guide.

    Science.gov (United States)

    Florida State Dept. of Education, Tallahassee. Div. of Vocational, Adult, and Community Education.

    This student guide together with an instructor guide comprise a set of curriculum materials on the criminal justice system. The student guide contains self-contained instructional material that students can study at their own pace most of the time. Six major subject areas or blocks, which are further broken down into several units, with some units…

  19. Criminal Justice Systems. Block I: Law Enforcement. Block II: The Courts. Block III: Corrections. Block IV: Community Relations. Block V: Proficiency Skills. Block VI: Criminalistics. Instructor Guide.

    Science.gov (United States)

    Florida State Dept. of Education, Tallahassee. Div. of Vocational, Adult, and Community Education.

    This instructor guide together with a student guide comprise a set of curriculum materials on the criminal justice system. The instructor guide is a resource for planning and managing individualized, competency-based instruction in six major subject areas or blocks, which are further broken down into several units with some units having several…

  20. Block by Block: Civic Action in the Battle of Baghdad

    Science.gov (United States)

    2007-11-01

    bedding, and latrine facilities. Additionally, provide milk , baby formula, diapers, 7 Bogart: Block by Block and infant/family care items such as...viable agricultural businesses. The cattle are a cross breed of a “regular” Iraqi cow and a water buffalo. Chicken farms are mostly egg farms, and...a problem. Contractors did not want to work for fear of being shot or kid - napped. For example, four contractors were shot over the duration of

  1. Harmony of spinning conformal blocks

    Energy Technology Data Exchange (ETDEWEB)

    Schomerus, Volker [DESY Hamburg, Theory Group,Notkestraße 85, 22607 Hamburg (Germany); Sobko, Evgeny [Nordita and Stockholm University,Roslagstullsbacken 23, SE-106 91 Stockholm (Sweden); Isachenkov, Mikhail [Department of Particle Physics and Astrophysics, Weizmann Institute of Science,Rehovot 7610001 (Israel)

    2017-03-15

    Conformal blocks for correlation functions of tensor operators play an increasingly important role for the conformal bootstrap programme. We develop a universal approach to such spinning blocks through the harmonic analysis of certain bundles over a coset of the conformal group. The resulting Casimir equations are given by a matrix version of the Calogero-Sutherland Hamiltonian that describes the scattering of interacting spinning particles in a 1-dimensional external potential. The approach is illustrated in several examples including fermionic seed blocks in 3D CFT where they take a very simple form.

  2. Harmony of spinning conformal blocks

    Energy Technology Data Exchange (ETDEWEB)

    Schomerus, Volker [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Theory Group; Sobko, Evgeny [Stockholm Univ. (Sweden); Nordita, Stockholm (Sweden); Isachenkov, Mikhail [Weizmann Institute of Science, Rehovoth (Israel). Dept. of Particle Physics and Astrophysics

    2016-12-07

    Conformal blocks for correlation functions of tensor operators play an increasingly important role for the conformal bootstrap programme. We develop a universal approach to such spinning blocks through the harmonic analysis of certain bundles over a coset of the conformal group. The resulting Casimir equations are given by a matrix version of the Calogero-Sutherland Hamiltonian that describes the scattering of interacting spinning particles in a 1-dimensional external potential. The approach is illustrated in several examples including fermionic seed blocks in 3D CFT where they take a very simple form.

  3. The SKINNY Family of Block Ciphers and Its Low-Latency Variant MANTIS

    DEFF Research Database (Denmark)

    Beierle, Christof; Jean, Jérémy; Kölbl, Stefan

    2016-01-01

    all known ciphers for ASIC round-based implementations, while still reaching an extremely small area for serial implementations and a very good efficiency for software and micro-controllers implementations (SKINNY has the smallest total number of AND/OR/XOR gates used for encryption process). Secondly...

  4. Left bundle-branch block

    DEFF Research Database (Denmark)

    Risum, Niels; Strauss, David; Sogaard, Peter

    2013-01-01

    The relationship between myocardial electrical activation by electrocardiogram (ECG) and mechanical contraction by echocardiography in left bundle-branch block (LBBB) has never been clearly demonstrated. New strict criteria for LBBB based on a fundamental understanding of physiology have recently...

  5. The wild tapered block bootstrap

    DEFF Research Database (Denmark)

    Hounyo, Ulrich

    -based method in terms of asymptotic accuracy of variance estimation and distribution approximation. For stationary time series, the asymptotic validity, and the favorable bias properties of the new bootstrap method are shown in two important cases: smooth functions of means, and M-estimators. The first......-order asymptotic validity of the tapered block bootstrap as well as the wild tapered block bootstrap approximation to the actual distribution of the sample mean is also established when data are assumed to satisfy a near epoch dependent condition. The consistency of the bootstrap variance estimator for the sample......In this paper, a new resampling procedure, called the wild tapered block bootstrap, is introduced as a means of calculating standard errors of estimators and constructing confidence regions for parameters based on dependent heterogeneous data. The method consists in tapering each overlapping block...

  6. Recursion Relations for Conformal Blocks

    CERN Document Server

    Penedones, João; Yamazaki, Masahito

    2016-09-12

    In the context of conformal field theories in general space-time dimension, we find all the possible singularities of the conformal blocks as functions of the scaling dimension $\\Delta$ of the exchanged operator. In particular, we argue, using representation theory of parabolic Verma modules, that in odd spacetime dimension the singularities are only simple poles. We discuss how to use this information to write recursion relations that determine the conformal blocks. We first recover the recursion relation introduced in 1307.6856 for conformal blocks of external scalar operators. We then generalize this recursion relation for the conformal blocks associated to the four point function of three scalar and one vector operator. Finally we specialize to the case in which the vector operator is a conserved current.

  7. Defying gravity using Jenga™ blocks

    Science.gov (United States)

    Tan, Yin-Soo; Yap, Kueh-Chin

    2007-11-01

    This paper describes how Jenga™ blocks can be used to demonstrate the physics of an overhanging tower that appears to defy gravity. We also propose ideas for how this demonstration can be adapted for the A-level physics curriculum.

  8. Semantic prioritization of novel causative genomic variants.

    Directory of Open Access Journals (Sweden)

    Imane Boudellioua

    2017-04-01

    Full Text Available Discriminating the causative disease variant(s for individuals with inherited or de novo mutations presents one of the main challenges faced by the clinical genetics community today. Computational approaches for variant prioritization include machine learning methods utilizing a large number of features, including molecular information, interaction networks, or phenotypes. Here, we demonstrate the PhenomeNET Variant Predictor (PVP system that exploits semantic technologies and automated reasoning over genotype-phenotype relations to filter and prioritize variants in whole exome and whole genome sequencing datasets. We demonstrate the performance of PVP in identifying causative variants on a large number of synthetic whole exome and whole genome sequences, covering a wide range of diseases and syndromes. In a retrospective study, we further illustrate the application of PVP for the interpretation of whole exome sequencing data in patients suffering from congenital hypothyroidism. We find that PVP accurately identifies causative variants in whole exome and whole genome sequencing datasets and provides a powerful resource for the discovery of causal variants.

  9. Semantic prioritization of novel causative genomic variants.

    Science.gov (United States)

    Boudellioua, Imane; Mahamad Razali, Rozaimi B; Kulmanov, Maxat; Hashish, Yasmeen; Bajic, Vladimir B; Goncalves-Serra, Eva; Schoenmakers, Nadia; Gkoutos, Georgios V; Schofield, Paul N; Hoehndorf, Robert

    2017-04-01

    Discriminating the causative disease variant(s) for individuals with inherited or de novo mutations presents one of the main challenges faced by the clinical genetics community today. Computational approaches for variant prioritization include machine learning methods utilizing a large number of features, including molecular information, interaction networks, or phenotypes. Here, we demonstrate the PhenomeNET Variant Predictor (PVP) system that exploits semantic technologies and automated reasoning over genotype-phenotype relations to filter and prioritize variants in whole exome and whole genome sequencing datasets. We demonstrate the performance of PVP in identifying causative variants on a large number of synthetic whole exome and whole genome sequences, covering a wide range of diseases and syndromes. In a retrospective study, we further illustrate the application of PVP for the interpretation of whole exome sequencing data in patients suffering from congenital hypothyroidism. We find that PVP accurately identifies causative variants in whole exome and whole genome sequencing datasets and provides a powerful resource for the discovery of causal variants.

  10. Conditionally replicating HIV and SIV variants

    NARCIS (Netherlands)

    Das, Atze T.; Berkhout, Ben

    2016-01-01

    Conditionally replicating human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) variants that can be switched on and off at will are attractive tools for HIV and SIV research. We constructed HIV and SIV variants in which the natural transcription control mechanism was replaced

  11. Adaptive ridge regression for rare variant detection.

    Directory of Open Access Journals (Sweden)

    Haimao Zhan

    Full Text Available It is widely believed that both common and rare variants contribute to the risks of common diseases or complex traits and the cumulative effects of multiple rare variants can explain a significant proportion of trait variances. Advances in high-throughput DNA sequencing technologies allow us to genotype rare causal variants and investigate the effects of such rare variants on complex traits. We developed an adaptive ridge regression method to analyze the collective effects of multiple variants in the same gene or the same functional unit. Our model focuses on continuous trait and incorporates covariate factors to remove potential confounding effects. The proposed method estimates and tests multiple rare variants collectively but does not depend on the assumption of same direction of each rare variant effect. Compared with the Bayesian hierarchical generalized linear model approach, the state-of-the-art method of rare variant detection, the proposed new method is easy to implement, yet it has higher statistical power. Application of the new method is demonstrated using the well-known data from the Dallas Heart Study.

  12. Adaptive ridge regression for rare variant detection.

    Science.gov (United States)

    Zhan, Haimao; Xu, Shizhong

    2012-01-01

    It is widely believed that both common and rare variants contribute to the risks of common diseases or complex traits and the cumulative effects of multiple rare variants can explain a significant proportion of trait variances. Advances in high-throughput DNA sequencing technologies allow us to genotype rare causal variants and investigate the effects of such rare variants on complex traits. We developed an adaptive ridge regression method to analyze the collective effects of multiple variants in the same gene or the same functional unit. Our model focuses on continuous trait and incorporates covariate factors to remove potential confounding effects. The proposed method estimates and tests multiple rare variants collectively but does not depend on the assumption of same direction of each rare variant effect. Compared with the Bayesian hierarchical generalized linear model approach, the state-of-the-art method of rare variant detection, the proposed new method is easy to implement, yet it has higher statistical power. Application of the new method is demonstrated using the well-known data from the Dallas Heart Study.

  13. Semantic prioritization of novel causative genomic variants

    KAUST Repository

    Boudellioua, Imene

    2017-04-17

    Discriminating the causative disease variant(s) for individuals with inherited or de novo mutations presents one of the main challenges faced by the clinical genetics community today. Computational approaches for variant prioritization include machine learning methods utilizing a large number of features, including molecular information, interaction networks, or phenotypes. Here, we demonstrate the PhenomeNET Variant Predictor (PVP) system that exploits semantic technologies and automated reasoning over genotype-phenotype relations to filter and prioritize variants in whole exome and whole genome sequencing datasets. We demonstrate the performance of PVP in identifying causative variants on a large number of synthetic whole exome and whole genome sequences, covering a wide range of diseases and syndromes. In a retrospective study, we further illustrate the application of PVP for the interpretation of whole exome sequencing data in patients suffering from congenital hypothyroidism. We find that PVP accurately identifies causative variants in whole exome and whole genome sequencing datasets and provides a powerful resource for the discovery of causal variants.

  14. Local binary patterns new variants and applications

    CERN Document Server

    Jain, Lakhmi; Nanni, Loris; Lumini, Alessandra

    2014-01-01

    This book introduces Local Binary Patterns (LBP), arguably one of the most powerful texture descriptors, and LBP variants. This volume provides the latest reviews of the literature and a presentation of some of the best LBP variants by researchers at the forefront of textual analysis research and research on LBP descriptors and variants. The value of LBP variants is illustrated with reported experiments using many databases representing a diversity of computer vision applications in medicine, biometrics, and other areas. There is also a chapter that provides an excellent theoretical foundation for texture analysis and LBP in particular. A special section focuses on LBP and LBP variants in the area of face recognition, including thermal face recognition. This book will be of value to anyone already in the field as well as to those interested in learning more about this powerful family of texture descriptors.

  15. Minority Variants of Drug-Resistant HIV

    Science.gov (United States)

    Gianella, Sara; Richman, Douglas D.

    2010-01-01

    Minor drug-resistant variants exist in every HIV-infected patient. Since these minority variants are usually present at very low levels, they cannot be detected and quantified using conventional genotypic and phenotypic tests. Recently, several assays have been developed to characterize these low-abundance drug-resistant variants in the large genetically complex population present in every HIV-infected individual. The most important issue is, what results generated by these assays can predict clinical or treatment outcomes and might guide patient management in clinical practice. Cutoff-values for the detection of these low-abundance viral variants that predict increased risk of treatment failure should be determined. These thresholds may be specific for each mutation and treatment regimen. In this review we summarize the attributes and limitations of the currently available detection assays and review the existing information about both acquired and transmitted drug resistant minority variants. PMID:20649427

  16. Fundamental Characteristics of Industrial Variant Specification Systems

    DEFF Research Database (Denmark)

    Hansen, Benjamin Loer; Hvam, Lars

    2004-01-01

    This paper focuses on the operational task of creating customised variants of industrial specifications (e.g. drawings, routings and bill-of-materials). Rooted in a lack of existing literature on the subject the paper describes the nature of variant specification systems. It introduces some...... fundamental concepts related to this task, which are relevant to understand for academia and practitioners working with the subject. This is done through a description of variant specification tasks and typical aspects of system solutions. To support the description of variant specification tasks and systems...... examples. In general the paper discusses an important focus area within mass customization and build-to-order production: the nature of industrial variant specification systems....

  17. Photocatalytic pavement blocks. Air purification by pavement blocks. Final results of the research at BRRC

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    The use of materials can influence to a large extent the environmental impact of traffic and of road infrastructure. Especially in urban areas, where the risk on smog formation during hot summer days is high, the use of photocatalytic pavement blocks can reduce the air pollution significantly. A project on environmental friendly concrete pavement blocks is conducted at the Belgian Road Research Centre. The use of photocatalytic material in the surface of pavement blocks to obtain air purifying materials is investigated. In contact with light, TiO2 as photocatalyst, is able to reduce the NO and NO2 content in the air, caused by the exhaust of traffic. The efficiency is tested on pavement blocks, but the technique can as well be applied on other road elements (e.g. noise reducing walls, linear elements) or as a coating on new materials or existing structures. At the previous TRA conference in Gotenborgh, Sweden, the principle of photocatalysis was presented. In this paper, emphasis will be put on the final results of the 4-year project obtained in laboratory as well as on site at the Leien of Antwerp (10,000 m{sup 2}). The results indicate a durable efficiency towards NOx reduction, which is in favour for the diminishing of the risk on ozone formation. However, the precise translation from the laboratory towards the site is still in question. The results obtained during the project are discussed in this paper.

  18. ELECTRICAL IMAGING AT THE LARGE BLOCK TEST YUCCA MOUNTAIN, NEVADA

    International Nuclear Information System (INIS)

    Ramirez, A.

    2000-01-01

    A monolithic block of densely welded tuff was excavated from a site on Fran Ridge near Yucca Mountain, Nevada so that coupled thermohydrological processes could be studied in a controlled, in situ experiment. A series of heaters were placed in a horizontal plane about 3 m from the top of the 3 m by 3 m by 4.5 m high block. Temperatures were measured at many points within and on the block surface and a suite of other measurements were taken to define the thermal and hydrologic response. Electrical resistance tomography (ERT) was used to map 2 dimensional images of moisture content changes along four planes in the block. The ERT images clearly delineate the drying and wetting of the rockmass during the 13 months of heating and subsequent six months of cool down. The main feature is a prominent dry zone that forms around the heaters then gradually disappears as the rock cools down. Other features include linear anomalies of decreasing moisture content which are fractures dehydrating as the block heats up. There are also examples of compact anomalies of wetting. Some of these appear to be water accumulation in fractures which are draining condensate from the block. Others may be rain water entering a fracture at the top of the block. During cooldown a general rewetting is observed although this is less certain because of poor data quality during this stage of the experiment

  19. The blocking reagent optimization for the magnetoelastic biosensor

    Science.gov (United States)

    Hu, Jiajia; Chai, Yating; Horikawa, Shin; Wikle, Howard C.; Wang, Feng'en; Du, Songtao; Chin, Bryan A.; Hu, Jing

    2015-06-01

    The wireless phage-based magnetoelastic (ME) biosensor has proven to be promising for real-time detection of pathogenic bacteria on fresh produces. The ME biosensor consists of a freestanding ME resonator as the signal transducer and filamentous phage as the biomolecular-recognition element, which can specifically bind to a pathogen of interest. Due to the Joule magnetostriction effect, the biosensors can be placed into mechanical resonance when subjected to a time-varying magnetic field alternating at the sensor's resonant frequency. Upon the attachment of the target pathogen, the mass of the biosensor increases, thereby decreasing its resonant frequency. This paper presents an investigation of blocking reagents immobilization for detecting Salmonella Typhimurium on fresh food surfaces. Three different blocking reagents (BSA, SuperBlock blocking buffer, and blocker BLOTTO) were used and compared. The optical microscope was used for bacterial cells binding observation. Student t-test was used to statistically analysis the experiment results. The results shows that SuperBlock blocking buffer and blocker BLOTTO have much better blocking performance than usually used BSA.

  20. Molecular genetic and clinical characterization of myotonic dystrophy type 1 patients carrying variant repeats within DMPK expansions.

    Science.gov (United States)

    Pešović, Jovan; Perić, S; Brkušanin, M; Brajušković, G; Rakočević-Stojanović, V; Savić-Pavićević, Dušanka

    2017-12-01

    Myotonic dystrophy type 1 (DM1) is caused by a highly unstable expansion of CTG repeats in the DMPK gene. Its huge phenotypic variability cannot be explained solely by the repeat number. Recently, variant repeats within the DMPK expansions have emerged as potential disease modifiers. The frequency of variant expanded alleles was estimated in 242 DM1 patients from 174 Serbian families using repeat-primed PCR (RP-PCR). The patterns of variant repeats were determined by direct sequencing of RP-PCR or PCR products. PCR-based southern blot was performed to get insight into the intergenerational mutational dynamics of variant expanded alleles. All patients carrying variant repeats were clinically re-examined. Variant repeats were observed in eight patients from five families (2.9%). They were detected only at the 3' end of DMPK expansions. CCG variant repeats were present in seven patients, either as a part of regular runs of CCGCTG hexamer, individual repeats, or CCG blocks. Analyses of three intergenerational transmissions revealed a considerable stability or likely a contraction of variant expanded alleles. Intriguingly, a decrease in age at onset accompanied these transmissions. Overall, patients were characterized by a milder phenotype and/or some atypical symptoms that could be rather clinically suggestive of myotonic dystrophy type 2. In addition, the first case of de novo CTC variant repeat was observed. Variant repeats might explain a part of the phenotypic variability in a small percent of DM1 patients and likely display a stabilizing effect on the meiotic instability of DMPK expanded alleles.

  1. Block Copolymer Metastability: Scientific Nightmare or Engineering Dream?

    Science.gov (United States)

    Bates, Frank S.

    1997-03-01

    Most experimental studies and almost all theories that deal with block copolymers, or mixtures of block copolymers and homopolymers, have been designed from an equilibrium perspective. Yet a myriad of factors conspire to retard approach to equilibrium in these systems, including: subtle features in the free energy surface that are controlled by ordered state symmetry; a coupling between microphase separation and entanglement dynamics; complex molecular architectures such as multiblock, starblock, and miktoarm. Even unentangled low molecular weight diblock copolymers, the simplest and dynamically least encumbered materials, exhibit long-lived metastable states that confound attempts to validate equilibrium theories. However, this apparent dilemma can be exploited through clever processing strategies. This lecture will address two opposing consequences of block copolymer metastability. The first is a potential nightmare: Can we ever establish universal block copolymer phase diagrams? The second is the stuff of dreams: Self-assembled thermoset nanocomposites.

  2. Systematic comparison of variant calling pipelines using gold standard personal exome variants.

    Science.gov (United States)

    Hwang, Sohyun; Kim, Eiru; Lee, Insuk; Marcotte, Edward M

    2015-12-07

    The success of clinical genomics using next generation sequencing (NGS) requires the accurate and consistent identification of personal genome variants. Assorted variant calling methods have been developed, which show low concordance between their calls. Hence, a systematic comparison of the variant callers could give important guidance to NGS-based clinical genomics. Recently, a set of high-confident variant calls for one individual (NA12878) has been published by the Genome in a Bottle (GIAB) consortium, enabling performance benchmarking of different variant calling pipelines. Based on the gold standard reference variant calls from GIAB, we compared the performance of thirteen variant calling pipelines, testing combinations of three read aligners--BWA-MEM, Bowtie2, and Novoalign--and four variant callers--Genome Analysis Tool Kit HaplotypeCaller (GATK-HC), Samtools mpileup, Freebayes and Ion Proton Variant Caller (TVC), for twelve data sets for the NA12878 genome sequenced by different platforms including Illumina2000, Illumina2500, and Ion Proton, with various exome capture systems and exome coverage. We observed different biases toward specific types of SNP genotyping errors by the different variant callers. The results of our study provide useful guidelines for reliable variant identification from deep sequencing of personal genomes.

  3. Cloning and characterization of functional subtype A HIV-1 envelope variants transmitted through breastfeeding.

    Science.gov (United States)

    Rainwater, Stephanie M J; Wu, Xueling; Nduati, Ruth; Nedellec, Rebecca; Mosier, Donald; John-Stewart, Grace; Mbori-Ngacha, Dorothy; Overbaugh, Julie

    2007-03-01

    Previous studies of HIV-1 variants transmitted from mother-to-infant have focused primarily on computational analyses of partial envelope gene sequences, rather than analyses of functional envelope variants. There are very few examples of well-characterized functional envelope clones from mother-infant pairs, especially from envelope variants representing the most prevalent subtypes worldwide. To address this, we amplified the envelope variants present in 4 mother-infant transmission pairs, all of whom were infected with subtype A and three of whom presumably transmitted HIV-1 during the breastfeeding period. Functional envelope clones were constructed, either encoding full-length envelope sequences from the mother and baby or by making chimeric envelope clones in a common backbone sequence. The infant envelope sequences were genetically homogeneous compared to the maternal viruses, and pseudoviruses bearing these envelopes all used CCR5 as a coreceptor. The infant viruses were generally resistant to neutralization by maternal antibodies present near the time of transmission. There were no notable differences in sensitivity of the mother and infant envelope variants to neutralization by heterologous plasma or monoclonal antibodies 2G12 and b12, or to inhibition by sCD4, PSC-RANTES or TAK779. This collection of viral envelopes, which can be used for making pseudotyped viruses, may be useful for examining the efficacy of interventions to block mother-infant transmission, including sera from vaccine candidates, purified antibodies under consideration for passive immunization and viral entry inhibitors.

  4. Realizing block planning concepts in make-and-pack production using MILP modelling and SAP APO

    DEFF Research Database (Denmark)

    Günther, H.O.; Grunow, M.; Neuhaus, U.

    2006-01-01

    In the industrial application environment considered, different variants of a basic product type are produced using the same resources and following the same basic process plan. To support production planning and scheduling for this type of production system, the concept of block planning...... is introduced, which has gained considerable attention, particularly in the consumer goods industry. A block represents a pre-defined sequence of production orders of variable size. In order to demonstrate the practical applicability of the proposed block planning concept, we consider the production system...... of a major producer of hair dyes as a case study. We present two different implementations of the block planning concept. One utilizes the Production Planning/Detailed Scheduling module of the SAP APO© software. The other approach is based on a mixed-integer linear programming formulation. In contrast...

  5. Somatic cancer variant curation and harmonization through consensus minimum variant level data

    Directory of Open Access Journals (Sweden)

    Deborah I. Ritter

    2016-11-01

    Full Text Available Abstract Background To truly achieve personalized medicine in oncology, it is critical to catalog and curate cancer sequence variants for their clinical relevance. The Somatic Working Group (WG of the Clinical Genome Resource (ClinGen, in cooperation with ClinVar and multiple cancer variant curation stakeholders, has developed a consensus set of minimal variant level data (MVLD. MVLD is a framework of standardized data elements to curate cancer variants for clinical utility. With implementation of MVLD standards, and in a working partnership with ClinVar, we aim to streamline the somatic variant curation efforts in the community and reduce redundancy and time burden for the interpretation of cancer variants in clinical practice. Methods We developed MVLD through a consensus approach by i reviewing clinical actionability interpretations from institutions participating in the WG, ii conducting extensive literature search of clinical somatic interpretation schemas, and iii survey of cancer variant web portals. A forthcoming guideline on cancer variant interpretation, from the Association of Molecular Pathology (AMP, can be incorporated into MVLD. Results Along with harmonizing standardized terminology for allele interpretive and descriptive fields that are collected by many databases, the MVLD includes unique fields for cancer variants such as Biomarker Class, Therapeutic Context and Effect. In addition, MVLD includes recommendations for controlled semantics and ontologies. The Somatic WG is collaborating with ClinVar to evaluate MVLD use for somatic variant submissions. ClinVar is an open and centralized repository where sequencing laboratories can report summary-level variant data with clinical significance, and ClinVar accepts cancer variant data. Conclusions We expect the use of the MVLD to streamline clinical interpretation of cancer variants, enhance interoperability among multiple redundant curation efforts, and increase submission of

  6. Various semiclassical limits of torus conformal blocks

    Energy Technology Data Exchange (ETDEWEB)

    Alkalaev, Konstantin [I.E. Tamm Department of Theoretical Physics, P.N. Lebedev Physical Institute,Leninsky ave. 53, Moscow, 119991 (Russian Federation); Department of General and Applied Physics, Moscow Institute of Physics and Technology,Institutskiy per. 7, Dolgoprudnyi, Moscow region, 141700 (Russian Federation); Geiko, Roman [Mathematics Department, National Research University Higher School of Economics,Usacheva str. 6, Moscow, 119048 (Russian Federation); Rappoport, Vladimir [I.E. Tamm Department of Theoretical Physics, P.N. Lebedev Physical Institute,Leninsky ave. 53, Moscow, 119991 (Russian Federation); Department of Quantum Physics, Institute for Information Transmission Problems,Bolshoy Karetny per. 19, Moscow, 127994 (Russian Federation)

    2017-04-12

    We study four types of one-point torus blocks arising in the large central charge regime. There are the global block, the light block, the heavy-light block, and the linearized classical block, according to different regimes of conformal dimensions. It is shown that the blocks are not independent being connected to each other by various links. We find that the global, light, and heavy-light blocks correspond to three different contractions of the Virasoro algebra. Also, we formulate the c-recursive representation of the one-point torus blocks which is relevant in the semiclassical approximation.

  7. Congenital and childhood atrioventricular blocks: pathophysiology and contemporary management.

    Science.gov (United States)

    Baruteau, Alban-Elouen; Pass, Robert H; Thambo, Jean-Benoit; Behaghel, Albin; Le Pennec, Solène; Perdreau, Elodie; Combes, Nicolas; Liberman, Leonardo; McLeod, Christopher J

    2016-09-01

    Atrioventricular block is classified as congenital if diagnosed in utero, at birth, or within the first month of life. The pathophysiological process is believed to be due to immune-mediated injury of the conduction system, which occurs as a result of transplacental passage of maternal anti-SSA/Ro-SSB/La antibodies. Childhood atrioventricular block is therefore diagnosed between the first month and the 18th year of life. Genetic variants in multiple genes have been described to date in the pathogenesis of inherited progressive cardiac conduction disorders. Indications and techniques of cardiac pacing have also evolved to allow safe permanent cardiac pacing in almost all patients, including those with structural heart abnormalities. Early diagnosis and appropriate management are critical in many cases in order to prevent sudden death, and this review critically assesses our current understanding of the pathogenetic mechanisms, clinical course, and optimal management of congenital and childhood AV block. • Prevalence of congenital heart block of 1 per 15,000 to 20,000 live births. AV block is defined as congenital if diagnosed in utero, at birth, or within the first month of life, whereas childhood AV block is diagnosed between the first month and the 18th year of life. As a result of several different etiologies, congenital and childhood atrioventricular block may occur in an entirely structurally normal heart or in association with concomitant congenital heart disease. Cardiac pacing is indicated in symptomatic patients and has several prophylactic indications in asymptomatic patients to prevent sudden death. • Autoimmune, congenital AV block is associated with a high neonatal mortality rate and development of dilated cardiomyopathy in 5 to 30 % cases. What is New: • Several genes including SCN5A have been implicated in autosomal dominant forms of familial progressive cardiac conduction disorders. • Leadless pacemaker technology and gene therapy for

  8. Block of neuronal chloride channels by tetraethylammonium ion derivatives.

    Science.gov (United States)

    Sanchez, D Y; Blatz, A L

    1995-11-01

    The block by the symmetric tetraethylammonium (TEA) ion derivatives tetrapropylammonium (TPrA), tetrabutylammonium (TBA), and tetrapentylammonium (TPeA) ions of fast chloride channels in acutely dissociated rat cortical neurons was studied with the excised inside-out configuration of the patch-clamp technique. When applied to the intracellular membrane surface, all three of the quaternary ammonium compounds (QAs) induced the appearance of short-lived closed states in a manner consistent with a blocking mechanism where the blocker preferentially binds to the open kinetic state and completely blocks ion current through the channel. The drug must leave the channel before the channel can return to a closed state. The mechanism of block was studied using one-dimensional dwell-time analysis. Kinetic models were fit to distributions of open and closed interval durations using the Q-matrix approach. The blocking rate constants for all three of the QAs were similar with values of approximately 12-20 x 10(6) M-1s-1. The unblocking rates were dependent on the size or hydrophobicity of the QA with the smallest derivative, TPrA, inducing a blocked state with a mean lifetime of approximately 90 microseconds, while the most hydrophobic derivative, TPeA, induced a blocked state with a mean lifetime of approximately 1 ms. Thus, it appears as though quaternary ammonium ion block of these chloride channels is nearly identical to the block of many potassium channels by these compounds. This suggests that there must be structural similarities in the conduction pathway between anion and cation permeable channels.

  9. Long-term weight-loss in gastric bypass patients carrying melanocortin 4 receptor variants.

    Directory of Open Access Journals (Sweden)

    Bryn S Moore

    Full Text Available The melanocortin 4 receptor (MC4R critically regulates feeding and satiety. Rare variants in MC4R are predominantly found in obese individuals. Though some rare variants in MC4R discovered in patients have defects in localization, ligand binding and signaling to cAMP, many have no recognized defects.In our cohort of 1433 obese subjects that underwent Roux-en-Y Gastric Bypass (RYGB surgery, we found fifteen variants of MC4R. We matched rare variant carriers to patients with the MC4R reference alleles for gender, age, starting BMI and T2D to determine the variant effect on weight-loss post-RYGB. In vitro, we determined expression of mutant receptors by ELISA and western blot, and cAMP production by microscopy.While carrying a rare MC4R allele is associated with obesity, carriers of rare variants exhibited comparable weight-loss after RYGB to non-carriers. However, subjects carrying three of these variants, V95I, I137T or L250Q, lost less weight after surgery. In vitro, the R305Q mutation caused a defect in cell surface expression while only the I137T and C326R mutations showed impaired cAMP signaling. Despite these apparent differences, there was no correlation between in vitro signaling and pre- or post-surgery clinical phenotype.These data suggest that subtle differences in receptor signaling conferred by rare MC4R variants combined with additional factors predispose carriers to obesity. In the absence of complete MC4R deficiency, these differences can be overcome by the powerful weight-reducing effects of bariatric surgery. In a complex disorder such as obesity, genetic variants that cause subtle defects that have cumulative effects can be overcome after appropriate clinical intervention.

  10. Synthesis of spatially variant lattices.

    Science.gov (United States)

    Rumpf, Raymond C; Pazos, Javier

    2012-07-02

    It is often desired to functionally grade and/or spatially vary a periodic structure like a photonic crystal or metamaterial, yet no general method for doing this has been offered in the literature. A straightforward procedure is described here that allows many properties of the lattice to be spatially varied at the same time while producing a final lattice that is still smooth and continuous. Properties include unit cell orientation, lattice spacing, fill fraction, and more. This adds many degrees of freedom to a design such as spatially varying the orientation to exploit directional phenomena. The method is not a coordinate transformation technique so it can more easily produce complicated and arbitrary spatial variance. To demonstrate, the algorithm is used to synthesize a spatially variant self-collimating photonic crystal to flow a Gaussian beam around a 90° bend. The performance of the structure was confirmed through simulation and it showed virtually no scattering around the bend that would have arisen if the lattice had defects or discontinuities.

  11. Genetic variants in toll-like receptors are not associated with rheumatoid arthritis susceptibility or anti-tumour necrosis factor treatment outcome

    DEFF Research Database (Denmark)

    Coenen, Marieke J H; Enevold, Christian; Barrera, Pilar

    2010-01-01

    Several studies point to a role of Toll-like receptors (TLRs) in the development of rheumatoid arthritis (RA). We investigated if genetic variants in TLR genes are associated with RA and response to tumour necrosis factor blocking (anti-TNF) medication.......Several studies point to a role of Toll-like receptors (TLRs) in the development of rheumatoid arthritis (RA). We investigated if genetic variants in TLR genes are associated with RA and response to tumour necrosis factor blocking (anti-TNF) medication....

  12. Radial Coordinates for Conformal Blocks

    CERN Document Server

    Hogervorst, Matthijs

    2013-01-01

    We develop the theory of conformal blocks in CFT_d expressing them as power series with Gegenbauer polynomial coefficients. Such series have a clear physical meaning when the conformal block is analyzed in radial quantization: individual terms describe contributions of descendants of a given spin. Convergence of these series can be optimized by a judicious choice of the radial quantization origin. We argue that the best choice is to insert the operators symmetrically. We analyze in detail the resulting "rho-series" and show that it converges much more rapidly than for the commonly used variable z. We discuss how these conformal block representations can be used in the conformal bootstrap. In particular, we use them to derive analytically some bootstrap bounds whose existence was previously found numerically.

  13. Diversity Gain through Antenna Blocking

    Directory of Open Access Journals (Sweden)

    V. Dehghanian

    2012-01-01

    Full Text Available As part of the typical usage mode, interaction between a handheld receiver antenna and the operator's RF absorbing body and nearby objects is known to generate variability in antenna radiation characteristics through blocking and pattern changes. It is counterintuitive that random variations in blocking can result in diversity gain of practical applicability. This diversity gain is quantified from a theoretical and experimental perspective. Measurements carried out at 1947.5 MHz verify the theoretical predictions, and a diversity gain of 3.1 dB was measured through antenna blocking and based on the utilized measurement setup. The diversity gain can be exploited to enhance signal detectability of handheld receivers based on a single antenna in indoor multipath environments.

  14. Cryptanalysis of Selected Block Ciphers

    DEFF Research Database (Denmark)

    Alkhzaimi, Hoda A.

    , pseudorandom number generators, and authenticated encryption designs. For this reason a multitude of initiatives over the years has been established to provide a secure and sound designs for block ciphers as in the calls for Data Encryption Standard (DES) and Advanced Encryption Standard (AES), lightweight...... ciphers initiatives, and the Competition for Authenticated Encryption: Security, Applicability, and Robustness (CAESAR). In this thesis, we first present cryptanalytic results on different ciphers. We propose attack named the Invariant Subspace Attack. It is utilized to break the full block cipher...... on the family of lightweight block cipher SIMON that was published by the U.S National Security Agency (NSA). The ciphers are developed with optimization towards both hardware and software in mind. While the specification paper discusses design requirements and performance of the presented lightweight ciphers...

  15. Climatological features of blocking anticyclones

    International Nuclear Information System (INIS)

    Lupo, A.R.; Smith, P.J.; Oglesby, R.J.

    1994-01-01

    Several climatological studies have been previously performed using large observational data sets (i.e., 10 years or longer) in order to determine the predominant characteristics of blocking anticyclones, including favored development regions, duration, preferred seasonal occurrence, and frequency of occurrence. These studies have shown that blocking anticyclones occur most frequently from October to April over the eastern Atlantic and Pacific oceans downstream from both the North American and Asian continental regions and the storm track regions to the east of these continents. Some studies have also revealed the presence of a third region block formation in western Russia near 40 degrees E which is associated with another storm track region over the Mediterranean and western Asia

  16. Projectors, shadows, and conformal blocks

    Energy Technology Data Exchange (ETDEWEB)

    Simmons-Duffin, David [Jefferson Physical Laboratory, Harvard University,Cambridge, MA 02138 (United States)

    2014-04-24

    We introduce a method for computing conformal blocks of operators in arbitrary Lorentz representations in any spacetime dimension, making it possible to apply bootstrap techniques to operators with spin. The key idea is to implement the “shadow formalism' of Ferrara, Gatto, Grillo, and Parisi in a setting where conformal invariance is manifest. Conformal blocks in d-dimensions can be expressed as integrals over the projective null-cone in the “embedding space' ℝ{sup d+1,1}. Taking care with their analytic structure, these integrals can be evaluated in great generality, reducing the computation of conformal blocks to a bookkeeping exercise. To facilitate calculations in four-dimensional CFTs, we introduce techniques for writing down conformally-invariant correlators using auxiliary twistor variables, and demonstrate their use in some simple examples.

  17. Ultrasonographic imaging of papillary thyroid carcinoma variants

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Jung Hee [Dept. of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2017-04-15

    Ultrasonography (US) is routinely used to evaluate thyroid nodules. The US features of papillary thyroid carcinoma (PTC), the most common thyroid malignancy, include hypoechogenicity, spiculated/microlobulated margins, microcalcifications, and a nonparallel orientation. However, many PTC variants have been identified, some of which differ from the classic type of PTC in terms of biological behavior and clinical outcomes. This review describes the US features and clinical implications of the variants of PTC. With the introduction of active surveillance replacing immediate biopsy or surgical treatment of indolent, small PTCs, an understanding of the US characteristics of PTC variants will facilitate the individualized management of patients with PTC.

  18. Histological variants of cutaneous Kaposi sarcoma

    Directory of Open Access Journals (Sweden)

    Pantanowitz Liron

    2008-07-01

    Full Text Available Abstract This review provides a comprehensive overview of the broad clinicopathologic spectrum of cutaneous Kaposi sarcoma (KS lesions. Variants discussed include: usual KS lesions associated with disease progression (i.e. patch, plaque and nodular stage; morphologic subtypes alluded to in the older literature such as anaplastic and telangiectatic KS, as well as several lymphedematous variants; and numerous recently described variants including hyperkeratotic, keloidal, micronodular, pyogenic granuloma-like, ecchymotic, and intravascular KS. Involuting lesions as a result of treatment related regression are also presented.

  19. GRL-09510, a Unique P2-Crown-Tetrahydrofuranylurethane -Containing HIV-1 Protease Inhibitor, Maintains Its Favorable Antiviral Activity against Highly-Drug-Resistant HIV-1 Variants in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Amano, Masayuki; Miguel Salcedo-Gómez, Pedro; Yedidi, Ravikiran S.; Delino, Nicole S.; Nakata, Hirotomo; Venkateswara Rao, Kalapala; Ghosh, Arun K.; Mitsuya, Hiroaki

    2017-09-25

    We report that GRL-09510, a novel HIV-1 protease inhibitor (PI) containing a newly-generated P2-crown-tetrahydrofuranylurethane (Crwn-THF), a P2'-methoxybenzene, and a sulfonamide isostere, is highly active against laboratory and primary clinical HIV-1 isolates (EC50: 0.0014–0.0028 μM) with minimal cytotoxicity (CC50: 39.0 μM). Similarly, GRL-09510 efficiently blocked the replication of HIV-1NL4-3 variants, which were capable of propagating at high-concentrations of atazanavir, lopinavir, and amprenavir (APV). GRL-09510 was also potent against multi-drug-resistant clinical HIV-1 variants and HIV-2ROD. Under the selection condition, where HIV-1NL4-3 rapidly acquired significant resistance to APV, an integrase inhibitor raltegravir, and a GRL-09510 congener (GRL-09610), no variants highly resistant against GRL-09510 emerged over long-term in vitro passage of the virus. Crystallographic analysis demonstrated that the Crwn-THF moiety of GRL-09510 forms strong hydrogen-bond-interactions with HIV-1 protease (PR) active-site amino acids and is bulkier with a larger contact surface, making greater van der Waals contacts with PR than the bis-THF moiety of darunavir. The present data demonstrate that GRL-09510 has favorable features for treating patients infected with wild-type and/or multi-drug-resistant HIV-1 variants, that the newly generated P2-Crwn-THF moiety confers highly desirable anti-HIV-1 potency. The use of the novel Crwn-THF moiety sheds lights in the design of novel PIs.

  20. Effects of loading sequences and size of repeated stress block of loads on fatigue life calculated using fatigue functions

    International Nuclear Information System (INIS)

    Schott, G.

    1989-01-01

    It is well-known that collective form, stress intensity and loading sequence of individual stresses as well as size of repeated stress blocks can influence fatigue life, significantly. The basic variant of the consecutive Woehler curve concept will permit these effects to be involved into fatigue life computation. The paper presented will demonstrate that fatigue life computations using fatigue functions reflect the loading sequence effect with multilevel loading precisely and provide reliable fatigue life data. Effects of size of repeated stress block and loading sequence on fatigue life as observed with block program tests can be reproduced using the new computation method. (orig.) [de

  1. Projectors, Shadows, and Conformal Blocks

    OpenAIRE

    Simmons-Duffin, David

    2012-01-01

    We introduce a method for computing conformal blocks of operators in arbitrary Lorentz representations in any spacetime dimension, making it possible to apply bootstrap techniques to operators with spin. The key idea is to implement the “shadow formalism” of Ferrara, Gatto, Grillo, and Parisi in a setting where conformal invariance is manifest. Conformal blocks in d -dimensions can be expressed as integrals over the projective null-cone in the “embedding space” $ \\mathbb{R} $ d +1,1 . Taking ...

  2. A new approach for reliability analysis with time-variant performance characteristics

    International Nuclear Information System (INIS)

    Wang, Zequn; Wang, Pingfeng

    2013-01-01

    Reliability represents safety level in industry practice and may variant due to time-variant operation condition and components deterioration throughout a product life-cycle. Thus, the capability to perform time-variant reliability analysis is of vital importance in practical engineering applications. This paper presents a new approach, referred to as nested extreme response surface (NERS), that can efficiently tackle time dependency issue in time-variant reliability analysis and enable to solve such problem by easily integrating with advanced time-independent tools. The key of the NERS approach is to build a nested response surface of time corresponding to the extreme value of the limit state function by employing Kriging model. To obtain the data for the Kriging model, the efficient global optimization technique is integrated with the NERS to extract the extreme time responses of the limit state function for any given system input. An adaptive response prediction and model maturation mechanism is developed based on mean square error (MSE) to concurrently improve the accuracy and computational efficiency of the proposed approach. With the nested response surface of time, the time-variant reliability analysis can be converted into the time-independent reliability analysis and existing advanced reliability analysis methods can be used. Three case studies are used to demonstrate the efficiency and accuracy of NERS approach

  3. RAGE splicing variants in mammals.

    Science.gov (United States)

    Sterenczak, Katharina Anna; Nolte, Ingo; Murua Escobar, Hugo

    2013-01-01

    The receptor for advanced glycation end products (RAGE) is a multiligand receptor of environmental stressors which plays key roles in pathophysiological processes, including immune/inflammatory disorders, Alzheimer's disease, diabetic arteriosclerosis, tumorigenesis, and metastasis. Besides the full-length RAGE protein in humans nearly 20 natural occurring RAGE splicing variants were described on mRNA and protein level. These naturally occurring isoforms are characterized by either N-terminally or C-terminally truncations and are discussed as possible regulators of the full-length RAGE receptor either by competitive ligand binding or by displacing the full-length protein in the membrane. Accordingly, expression deregulations of the naturally occurring isoforms were supposed to have significant effect on RAGE-mediated disorders. Thereby the soluble C-truncated RAGE isoforms present in plasma and tissues are the mostly focused isoforms in research and clinics. Deregulations of the circulating levels of soluble RAGE forms were reported in several RAGE-associated pathological disorders including for example atherosclerosis, diabetes, renal failure, Alzheimer's disease, and several cancer types. Regarding other mammalian species, the canine RAGE gene showed high similarities to the corresponding human structures indicating RAGE to be evolutionary highly conserved between both species. Similar to humans the canine RAGE showed a complex and extensive splicing activity leading to a manifold pattern of RAGE isoforms. Due to the similarities seen in several canine and human diseases-including cancer-comparative structural and functional analyses allow the development of RAGE and ligand-specific therapeutic approaches beneficial for human and veterinary medicine.

  4. Development of industrial variant specification systems

    DEFF Research Database (Denmark)

    Hansen, Benjamin Loer

    acquisition and order fulfilment, i.e. the creation of drawings, bill-of-materials, routings, product descriptions, quote letters etc. The present thesis is rooted in the assumption that variant specification systems supporting the cross-functional processes of order acquisition and order fulfilment must...... be developed from a holistic and strategically anchored point of view. Another assumption is that this is a challenge for many industrial companies. Even though the literature presents many considerations on general issues covering new information technology, little work is found on the business perspectives...... to the four research tasks of the Ph.D. project: • Define and describe the variant specification system. • Create a procedure for the development of variant specification systems. • Create concepts, methods and tools to support the analysis and determination of the variant specification task. • Identify...

  5. Development of industrial variant specification systems

    DEFF Research Database (Denmark)

    Hansen, Benjamin Loer

    With globalisation and increased competition industrial companies must be prepared to satisfy individual customer needs and still stay competitive with regards to lead times, quality, and prices. These factors require companies to be better prepared to handle specification activities during order...... to the four research tasks of the Ph.D. project: • Define and describe the variant specification system. • Create a procedure for the development of variant specification systems. • Create concepts, methods and tools to support the analysis and determination of the variant specification task. • Identify...... are presented for analysing and determining the variant specification task. These are grouped in external and internal task variables. Additionally functional characteristics, which can be used for defining performance measures, are defined. Based in the concept of “focus” different levels of tasks...

  6. Fluorosilicone multi-block copolymers tethering quaternary ammonium salt groups for antimicrobial purpose

    International Nuclear Information System (INIS)

    Zhou, Fang; Qin, Xiaoshuai; Li, Yancai; Ren, Lixia; Zhao, Yunhui; Yuan, Xiaoyan

    2015-01-01

    Highlights: • QAS-containing fluorosilicone multi-block copolymers were synthesized. • The block length of PHFBMA in the copolymers was tailored via RAFT polymerization. • Surface roughness of the copolymers decreased with the increased PHFBMA content. • A certain length of PHFBMA block enhanced C−N + percentage on the surface. - Abstract: Symmetrically structured fluorosilicone multi-block copolymers containing poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) and poly(hexafluorobutyl methacrylate) (PHFBMA) were sequentially synthesized via reversible addition–fragmentation chain transfer polymerization, using a polydimethylsiloxane (PDMS) chain transfer agent with dithiocarbonate groups at both ends. Then, the CBABC-type block copolymers were quaternized with n-octyliodide to tether quaternary ammonium salt (QAS) groups in the PDMAEMA blocks for the antimicrobial use. The obtained fluorosilicone copolymers showed clear variations in the C-N + composition and surface morphology on their films depending on the content of the PHFBMA blocks, which were characterized by X-ray photoelectron spectroscopy and atomic force microscopy, respectively. The results indicated that the symmetrical CBABC structure favored PDMS and QAS tethered blocks migrating to the film surface. With the mass percentage of the PHFBMA increased from 0 to 32.5%, the surface roughness of the copolymer film decreased gradually with a tendency to form a smooth surface. Owing to the surface properties, fluorosilicone multi-block copolymers containing a certain amount of PHFBMA with higher C-N + content and relatively smooth morphology demonstrated obvious antimicrobial activity against Gram-positive bacteria, Bacillus subtilis and Gram-negative bacteria, Escherichia coli. The functionalized multi-block copolymers based on fluorosilicone and QAS groups would have potential applications in antimicrobial coatings

  7. Fluorosilicone multi-block copolymers tethering quaternary ammonium salt groups for antimicrobial purpose

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Fang; Qin, Xiaoshuai; Li, Yancai; Ren, Lixia; Zhao, Yunhui, E-mail: zhaoyunhui@tju.edu.cn; Yuan, Xiaoyan

    2015-08-30

    Highlights: • QAS-containing fluorosilicone multi-block copolymers were synthesized. • The block length of PHFBMA in the copolymers was tailored via RAFT polymerization. • Surface roughness of the copolymers decreased with the increased PHFBMA content. • A certain length of PHFBMA block enhanced C−N{sup +} percentage on the surface. - Abstract: Symmetrically structured fluorosilicone multi-block copolymers containing poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) and poly(hexafluorobutyl methacrylate) (PHFBMA) were sequentially synthesized via reversible addition–fragmentation chain transfer polymerization, using a polydimethylsiloxane (PDMS) chain transfer agent with dithiocarbonate groups at both ends. Then, the CBABC-type block copolymers were quaternized with n-octyliodide to tether quaternary ammonium salt (QAS) groups in the PDMAEMA blocks for the antimicrobial use. The obtained fluorosilicone copolymers showed clear variations in the C-N{sup +} composition and surface morphology on their films depending on the content of the PHFBMA blocks, which were characterized by X-ray photoelectron spectroscopy and atomic force microscopy, respectively. The results indicated that the symmetrical CBABC structure favored PDMS and QAS tethered blocks migrating to the film surface. With the mass percentage of the PHFBMA increased from 0 to 32.5%, the surface roughness of the copolymer film decreased gradually with a tendency to form a smooth surface. Owing to the surface properties, fluorosilicone multi-block copolymers containing a certain amount of PHFBMA with higher C-N{sup +} content and relatively smooth morphology demonstrated obvious antimicrobial activity against Gram-positive bacteria, Bacillus subtilis and Gram-negative bacteria, Escherichia coli. The functionalized multi-block copolymers based on fluorosilicone and QAS groups would have potential applications in antimicrobial coatings.

  8. Main-chain supramolecular block copolymers.

    Science.gov (United States)

    Yang, Si Kyung; Ambade, Ashootosh V; Weck, Marcus

    2011-01-01

    Block copolymers are key building blocks for a variety of applications ranging from electronic devices to drug delivery. The material properties of block copolymers can be tuned and potentially improved by introducing noncovalent interactions in place of covalent linkages between polymeric blocks resulting in the formation of supramolecular block copolymers. Such materials combine the microphase separation behavior inherent to block copolymers with the responsiveness of supramolecular materials thereby affording dynamic and reversible materials. This tutorial review covers recent advances in main-chain supramolecular block copolymers and describes the design principles, synthetic approaches, advantages, and potential applications.

  9. Building Blocks for Personal Brands

    Science.gov (United States)

    Thomas, Lisa Carlucci

    2011-01-01

    In this article, the author discusses the four essential building blocks for personal brands: (1) name; (2) message; (3) channels; and (4) bridges. However, outstanding building materials can only take a person so far. The author emphasizes that vision, determination, faith, a sense of humor, and humility are also required.

  10. Control rod removal blocking device

    International Nuclear Information System (INIS)

    Yoshioka, Ritsuo.

    1981-01-01

    Purpose: To prevent excess power increase resulted from erroneous control rod removal during high power operation in BWR type reactor by decreasing the continuous removal enabling distance for the control rods along with increase in the reactor power where the reactor power is greater than a predetermined level. Constitution: When control rod selection signals are supplied from a control unit to a control rod removal blocking device, the blocking device judges whether the reactor core power is greater than a predetermined value A or not, using reactor core power signals outputted from an average power monitor. Where the reactor core power exceeds the predetermined value A and if the reactor core power is relatively low, a large continuous removal enabling distance N 1 is calculated in the blocking device to allow the continuous removal as far as the notch N 1 . The continuous removal enabling distance is shortened as the reactor core power increases and the removal is blocked, for example, at notch N 2 . While on the other hand, if the reactor core power is below the predetermined value A, both of the notchwise removal and the continuous removal are enabled. (Seki, T.)

  11. First Degree Pacemaker Exit Block

    Directory of Open Access Journals (Sweden)

    Johnson Francis

    2016-10-01

    Full Text Available Usually atrial and ventricular depolarizations follow soon after the pacemaker stimulus (spike on the ECG. But there can be an exit block due to fibrosis at the electrode - tissue interface at the lead tip. This can increase the delay between the spike and atrial or ventricular depolarization.

  12. Vagal Blocking for Obesity Control

    DEFF Research Database (Denmark)

    Johannessen, Helene; Revesz, David; Kodama, Yosuke

    2017-01-01

    BACKGROUND: Recently, the US FDA has approved "vagal blocking therapy or vBLoc® therapy" as a new treatment for obesity. The aim of the present study was to study the mechanism-of-action of "VBLOC" in rat models. METHODS: Rats were implanted with VBLOC, an intra-abdominal electrical device...

  13. Thermo-responsive block copolymers

    NARCIS (Netherlands)

    Mocan Cetintas, Merve

    2017-01-01

    Block copolymers (BCPs) are remarkable materials because of their self-assembly behavior into nano-sized regular structures and high tunable properties. BCPs are in used various applications such as surfactants, nanolithography, biomedicine and nanoporous membranes. In these thesis, we aimed to

  14. Scintigraphic visualization of 'Blocking' thyroid

    International Nuclear Information System (INIS)

    Simeonova, A.; Kostadinova, I.

    2006-01-01

    Full text: An important problem in nuclear endocrinology is 'blocking' of thyroid gland, which necessitates postpone of the investigation, adverse clinical effect of stopping medications and a delay of making diagnosis. The aim of the study was to introduce and to determine the clinical value of the scintigraphy with 99mTc-MIBI in patients (Pts) with 'blocked thyroid'. In 365 Pts (aged 38-75 years), indicated for a thyroid scintigraphy after proper preparation, an investigation was performed with 74 MBq 99mTc-pertechnetate, 20 min. p.i. In 14 of them (3.8%), the thyroid was 'blocked' and additional scintigraphy was done with 370-555 MBq 99mTc-MIBI, 15 and 120 min.p.i. It was estimated that in all Pts there was a visualization of thyroid. In 1 of them, a large 'hot' nodule was visualized in the early and late image. Later on a differentiated thyroid carcinoma was proved histologically. In the rest of the patients 'cold' nodules with different size were visualized, eventually as a result of cysts. As a conclusion we consider, that a scintigraphy with 99mTc-MIBI is a useful tool in Pts with 'blocked' thyroid. In addition an evaluation of the thyroid nodule could be done and therefore- a recommendation for therapy

  15. A Bullet-Block Experiment that Explains the Chain Fountain

    Science.gov (United States)

    Pantaleone, J.; Smith, R.

    2018-05-01

    It is common in science for two phenomena to appear to be very different, but in fact follow from the same basic principles. Here we consider such a case, the connection between the chain fountain and a bullet-block collision experiment. When an upward moving bullet strikes a wooden block resting on a horizontal table, the block will rise to a higher height when the bullet strikes near the end of the block. This is because the quickly rotating block experiences an additional upward "reaction" force from its contact with the table. Such a reaction force also explains the chain fountain. When a chain falls from a pile in a container to the floor below, the chain rises up above the container. This rise occurs because the quickly rotating links in the container push off of the surface beneath them. We derive a model that accurately describes our measurements in the bullet-block experiment, and then use this same model to calculate an approximate expression for the distance the chain rises above the container. More extensive discussions of the chain fountain are available elsewhere.

  16. Block Textured a-Si:H Solar Cell

    Directory of Open Access Journals (Sweden)

    Seung Jae Moon

    2014-01-01

    Full Text Available A series of etching experiments on light trapping structure have been carried out by glass etching. The block structure provides long light traveling path and a constant distance between the cathode and anode electrodes regardless of the block height, which results in higher efficiency of the block textured solar cell. In terms of etching profile of the glass substrate, the addition of NH4F resulted in the smooth and clean etching profile, and the steep slope of the block was obtained by optimizing the composition of etching solution. For a higher HF concentration, a more graded slope was obtained and the addition of HNO3 and NH4F provided steep slope and clean etching profile. The effects of the block textured glass were verified by a comparison of the solar cell efficiency. For the textured solar cell, the surface was much rougher than that of the plain glass, which also contributes to the improvement of the efficiency. We accomplished block shaped light trapping structure for the first time by wet etching of the glass substrate, which enables the high efficiency thin film solar cell with the aid of the good step coverage deposition.

  17. TREM2 Variants in Alzheimer's Disease

    Science.gov (United States)

    Guerreiro, Rita; Wojtas, Aleksandra; Bras, Jose; Carrasquillo, Minerva; Rogaeva, Ekaterina; Majounie, Elisa; Cruchaga, Carlos; Sassi, Celeste; Kauwe, John S.K.; Younkin, Steven; Hazrati, Lilinaz; Collinge, John; Pocock, Jennifer; Lashley, Tammaryn; Williams, Julie; Lambert, Jean-Charles; Amouyel, Philippe; Goate, Alison; Rademakers, Rosa; Morgan, Kevin; Powell, John; St. George-Hyslop, Peter; Singleton, Andrew; Hardy, John

    2013-01-01

    BACKGROUND Homozygous loss-of-function mutations in TREM2, encoding the triggering receptor expressed on myeloid cells 2 protein, have previously been associated with an autosomal recessive form of early-onset dementia. METHODS We used genome, exome, and Sanger sequencing to analyze the genetic variability in TREM2 in a series of 1092 patients with Alzheimer's disease and 1107 controls (the discovery set). We then performed a meta-analysis on imputed data for the TREM2 variant rs75932628 (predicted to cause a R47H substitution) from three genomewide association studies of Alzheimer's disease and tested for the association of the variant with disease. We genotyped the R47H variant in an additional 1887 cases and 4061 controls. We then assayed the expression of TREM2 across different regions of the human brain and identified genes that are differentially expressed in a mouse model of Alzheimer's disease and in control mice. RESULTS We found significantly more variants in exon 2 of TREM2 in patients with Alzheimer's disease than in controls in the discovery set (P = 0.02). There were 22 variant alleles in 1092 patients with Alzheimer's disease and 5 variant alleles in 1107 controls (P<0.001). The most commonly associated variant, rs75932628 (encoding R47H), showed highly significant association with Alzheimer's disease (P<0.001). Meta-analysis of rs75932628 genotypes imputed from genomewide association studies confirmed this association (P = 0.002), as did direct genotyping of an additional series of 1887 patients with Alzheimer's disease and 4061 controls (P<0.001). Trem2 expression differed between control mice and a mouse model of Alzheimer's disease. CONCLUSIONS Heterozygous rare variants in TREM2 are associated with a significant increase in the risk of Alzheimer's disease. (Funded by Alzheimer's Research UK and others.) PMID:23150934

  18. Molecular Characterization of Attenuated Junin Virus Variants.

    Science.gov (United States)

    1992-07-14

    AD-A260 128 AD____ MOLECULAR CHARACTERIZATION OF ATTENUATED JUNIN VIRUS VARIANTS FINAL REPORT VICTOR ROMANOWSKI PABLO D. GHIRINGHELLI CESAR G...Virus Variants 12. PERSONAL AUTHOR(S) Victor Romanowski , Pablo D. Ghiringhelli, Cesar G. Albarino, & Mariel Piboul 13a. TYPE OF REPORT 13b. TIME... Romanowski and Bishop, 1985; Clegg and Oram, 1985; Franze-Fern ndez et al., 1987). The GPC protein (ca. 57 kDa in the unglycosylated form) is translated from a

  19. Genetic Variants Associated with Colorectal Adenoma Susceptibility.

    Directory of Open Access Journals (Sweden)

    Anna Abulí

    Full Text Available Common low-penetrance genetic variants have been consistently associated with colorectal cancer risk.To determine if these genetic variants are associated also with adenoma susceptibility and may improve selection of patients with increased risk for advanced adenomas and/or multiplicity (≥ 3 adenomas.We selected 1,326 patients with increased risk for advanced adenomas and/or multiplicity and 1,252 controls with normal colonoscopy from population-based colorectal cancer screening programs. We conducted a case-control association study analyzing 30 colorectal cancer susceptibility variants in order to investigate the contribution of these variants to the development of subsequent advanced neoplasia and/or multiplicity.We found that 14 of the analyzed genetic variants showed a statistically significant association with advanced adenomas and/or multiplicity: the probability of developing these lesions increased with the number of risk alleles reaching a 2.3-fold risk increment in individuals with ≥ 17 risk alleles.Nearly half of the genetic variants associated with colorectal cancer risk are also related to advanced adenoma and/or multiplicity predisposition. Assessing the number of risk alleles in individuals within colorectal cancer screening programs may help to identify better a subgroup with increased risk for advanced neoplasia and/or multiplicity in the general population.

  20. An equine infectious anemia virus variant superinfects cells through novel receptor interactions.

    Science.gov (United States)

    Brindley, Melinda A; Zhang, Baoshan; Montelaro, Ronald C; Maury, Wendy

    2008-10-01

    Wild-type strains of equine infectious anemia virus (EIAV) prevent superinfection of previously infected cells. A variant strain of virus that spontaneously arose during passage, EIAV(vMA-1c), can circumvent this mechanism in some cells, such as equine dermis (ED) cells, but not in others, such as equine endothelial cells. EIAV(vMA-1c) superinfection of ED cells results in a buildup of unintegrated viral DNA and rapid killing of the cell monolayer. Here, we examined the mechanism of resistance that is used by EIAV to prevent superinfection and explored the means by which EIAV(vMA-1c) overcomes this restriction. We found that the cellular receptor used by EIAV, equine lentivirus receptor 1 (ELR1), remains on the surface of cells chronically infected with EIAV, suggesting that wild-type EIAV interferes with superinfection by masking ELR1. The addition of soluble wild-type SU protein to the medium during infection blocked infection by wild-type strains of virus, implicating SU as the viral protein responsible for interfering with virion entry into previously infected cells. Additionally, interference of wild-type EIAV binding to ELR1 by the addition of either anti-ELR1 antibodies or the ELR1 ectodomain prevented entry of the wild-type strains of EIAV into two permissive cell populations. Many of these same interference treatments prevented EIAV(vMA-1c) infection of endothelial cells but only modestly affected the ability of EIAV(vMA-1c) to enter and kill previously infected ED cells. These findings indicate that EIAV(vMA-1c) retains the ability to use ELR1 for entry and suggest that this virus can interact with an additional, unidentified receptor to superinfect ED cells.

  1. Structural insight into a novel human CCR5-V130I variant associated with resistance to HIV-1 infection.

    Science.gov (United States)

    Stambouli, Nejla; Wei, Ning-Ning; Jlizi, Asma; Aissa, Samah; Abdelmalek, Rim; Kilani, Baderredine; Slim, Amine; Tiouiri, Ben Aissa Hanen; Dridi, Mahdi; Hamza, Adel; Ben Ammar Elgaied, Amel

    2014-01-01

    We report the identification of a novel CC chemokine receptor 5 (CCR5) variant that seems associated with resistance to HIV-1 infection. The V130I mutation of the CCR5 receptor is located in the intracellular loop ICL2 known as DRY box and described in the literature as a nonsynonymous mutation present in nonhuman primates group. Extensive molecular modeling and dynamics simulations were performed to elucidate the mechanism by which the V130I mutation may induce conformational change of the CCR5 folding protein and prevent the interaction with the β-arrestin protein. Our study provides new mechanistic insight into how a specific mutation in the regulatory domain of CCR5 might alter the structural folding of the DRY box and the possible ICL2 loop binding with the β-arrestin protein, as described in our previous computational study. The results from our large-scale simulations complement recent experimental results and clinical features and offer useful insights into the mechanism behind CCR5 protein folding and signal transduction. In order for HIV, the entry of the virus to the cells must fuse with the CCR5 receptor that sits on the surface of T-helper immune cells. The described V130I mutation in the gene encoding the CCR5 protein may results in a defective CCR5-Arrestin binding complex that blocks entry of the virus.

  2. Collisions of slow polyatomic ions with surfaces: Dissociation and chemical reactions of C2H2+center dot, C2H3+, C2H4+center dot C2H5+, and their deuterated variants C2D2+center dot and C2D4+center dot on room-temperature and heated carbon surfaces

    Czech Academy of Sciences Publication Activity Database

    Jašík, J.; Žabka, Ján; Feketeová, L.; Ipolyi, I.; Märk, T. D.; Herman, Zdeněk

    2005-01-01

    Roč. 109, č. 45 (2005), s. 10208-10215 ISSN 1089-5639 R&D Projects: GA AV ČR IAA4040405; GA AV ČR KSK4040110; GA MŠk LC510 Institutional research plan: CEZ:AV0Z40400503 Keywords : physical chemistry * ion-surface collisions * hydrocarbons Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.898, year: 2005

  3. 31 CFR 585.216 - Expenses of maintaining blocked property; liquidation into blocked account.

    Science.gov (United States)

    2010-07-01

    ... property; liquidation into blocked account. 585.216 Section 585.216 Money and Finance: Treasury Regulations... blocked property; liquidation into blocked account. (a) Except as otherwise authorized, and... expenses incident to the blocking and maintenance of property blocked pursuant to § 585.201 or § 585.215(a...

  4. On the Eigenvalues and Eigenvectors of Block Triangular Preconditioned Block Matrices

    KAUST Repository

    Pestana, Jennifer

    2014-01-01

    Block lower triangular matrices and block upper triangular matrices are popular preconditioners for 2×2 block matrices. In this note we show that a block lower triangular preconditioner gives the same spectrum as a block upper triangular preconditioner and that the eigenvectors of the two preconditioned matrices are related. © 2014 Society for Industrial and Applied Mathematics.

  5. Beta-glucosidase variants and polynucleotides encoding same

    Energy Technology Data Exchange (ETDEWEB)

    Wogulis, Mark; Harris, Paul; Osborn, David

    2017-06-27

    The present invention relates to beta-glucosidase variants, e.g. beta-glucosidase variants of a parent Family GH3A beta-glucosidase from Aspergillus fumigatus. The present invention also relates to polynucleotides encoding the beta-glucosidase variants; nucleic acid constructs, vectors, and host cells comprising the polynucleotides; and methods of using the beta-glucosidase variants.

  6. Rapid, Brushless Self-assembly of a PS-b-PDMS Block Copolymer for Nanolithography

    DEFF Research Database (Denmark)

    Rasappa, Sozaraj; Schulte, Lars; Borah, Dipu

    2014-01-01

    by grafting of a brush layer that renders the surface energy neutral relative to the constituent blocks. We provide here a first study on rapid, low temperature self-assembly of PS-b-PDMS (polystyrene-block-polydimethylsiloxane) on silicon substrates without a brush layer. We show that it forms line...

  7. Evaluating small-body landing hazards due to blocks

    Science.gov (United States)

    Ernst, C.; Rodgers, D.; Barnouin, O.; Murchie, S.; Chabot, N.

    2014-07-01

    Introduction: Landed missions represent a vital stage of spacecraft exploration of planetary bodies. Landed science allows for a wide variety of measurements essential to unraveling the origin and evolution of a body that are not possible remotely, including but not limited to compositional measurements, microscopic grain characterization, and the physical properties of the regolith. To date, two spacecraft have performed soft landings on the surface of a small body. In 2001, the Near Earth Asteroid Rendezvous (NEAR) mission performed a controlled descent and landing on (433) Eros following the completion of its mission [1]; in 2005, the Hayabusa spacecraft performed two touch-and-go maneuvers at (25143) Itokawa [2]. Both landings were preceded by rendezvous spacecraft reconnaissance, which enabled selection of a safe landing site. Three current missions have plans to land on small bodies (Rosetta, Hayabusa 2, and OSIRIS-REx); several other mission concepts also include small-body landings. Small-body landers need to land at sites having slopes and block abundances within spacecraft design limits. Due to the small scale of the potential hazards, it can be difficult or impossible to fully characterize a landing surface before the arrival of the spacecraft at the body. Although a rendezvous mission phase can provide global reconnaissance from which a landing site can be chosen, reasonable a priori assurance that a safe landing site exists is needed to validate the design approach for the spacecraft. Method: Many robotic spacecraft have landed safely on the Moon and Mars. Images of these landing sites, as well as more recent, extremely high-resolution orbital datasets, have enabled the comparison of orbital block observations to the smaller blocks that pose hazards to landers. Analyses of the Surveyor [3], Viking 1 and 2, Mars Pathfinder, Phoenix, Spirit, Opportunity, and Curiosity landing sites [4--8] have indicated that for a reasonable difference in size (a factor

  8. Block-Matching Based Multifocus Image Fusion

    Directory of Open Access Journals (Sweden)

    Feng Zhu

    2015-01-01

    Full Text Available A new multifocus image fusion method is proposed. Two image blocks are selected by sliding the window from the two source images at the same position, discrete cosine transform (DCT is implemented, respectively, on these two blocks, and the alternating component (AC energy of these blocks is then calculated to decide which is the well-focused one. In addition, block matching is used to determine a group of image blocks that are all similar to the well-focused reference block. Finally, all the blocks are returned to their original positions through weighted average. The weight is decided with the AC energy of the well-focused block. Experimental results demonstrate that, unlike other spatial methods, the proposed method effectively avoids block artifacts. The proposed method also significantly improves the objective evaluation results, which are obtained by some transform domain methods.

  9. Blocking incidental frustration during bargaining.

    Science.gov (United States)

    Vargas, Maria Esperanza S; Brown, Anna-Leigh; Durkee, Cassandra M; Sim, Hoeun

    2018-02-08

    The current study examined the effects of an intervention aimed at blocking the transfer of frustration from a previous experience (i.e. recall task) to a subsequent and unrelated task (i.e. ultimatum bargaining task). Participants who went through the intervention were more likely to accept unfair offers in the ultimatum bargaining task than those who did not go through the intervention. These results show that participants who were blocked from transferring their feelings of frustration from the recall task to the subsequent bargaining task (no-transfer condition) more likely accepted unfair offers than those who inadvertently transferred their feelings of frustration (transfer condition). The effect of conditions on accept-reject decisions in the ultimatum bargaining was mediated by reported feelings of frustration.

  10. Frequency of thermostability variants: estimation of total rare variant frequency in human populations

    Energy Technology Data Exchange (ETDEWEB)

    Mohrenweiser, H.W.; Neel, J.V.

    1981-09-01

    Eight erythrocyte enzymes were examine for thermostability in an unselected sample of 100 newborn infants. Three thermolabile variants, one each of lactate dehydrogenase, glucosephosphate isomerase, and glucose-6-phosphate dehydrogenase, were identified, none of which was detectable as a variant by standard electrophoretic techniques. All were inherited. This frequency of 3.8 heritable thermostability variants per 1000 determinations is to be compared with a frequency of electrophoretically detectable variants of 1.1 per 1000 determinations, a frequency of 2.4 enzyme-deficiency variants per 1000 determinations, and a frequency of individuals with rare enzyme deficiency or electrophoretic or thermostability (or both) variants at these loci is 8.4 per 1000 determinations. A similar distribution and frequency is seen when the comparison is limited to the seven loci studied by all techniques. it is clear that not all of the electrophoretic and thermostability variants present in the population are detected by the techniques used in this study. Accordingly, it is estimated that the true frequency of carriers of a rare variant for each of these enzyme-coding loci averages greater than 10/1000. Some implications of these frequencies for human disease are discussed.

  11. Physical tuning of cellulose-polymer interactions utilizing cationic block copolymers based on PCL and quaternized PDMAEMA.

    Science.gov (United States)

    Utsel, Simon; Bruce, Carl; Pettersson, Torbjörn; Fogelström, Linda; Carlmark, Anna; Malmström, Eva; Wågberg, Lars

    2012-12-01

    In this work, the objective was to synthesize and evaluate the properties of a compatibilizer based on poly(ε-caprolactone) aimed at tuning the surface properties of cellulose fibers used in fiber-reinforced biocomposites. The compatibilizer is an amphiphilic block copolymer consisting of two different blocks which have different functions. One block is cationic, quaternized poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) and can therefore electrostatically attach to anionic reinforcing materials such as cellulose-based fibers/fibrils under mild conditions in water. The other block consists of poly(ε-caprolactone) (PCL) which can decrease the surface energy of a cellulose surface and also has the ability to form physical entanglements with a PCL surface thereby improving the interfacial adhesion. Atom Transfer Radical Polymerization (ATRP) and Ring-Opening Polymerization (ROP) were used to synthesize three block copolymers with the same length of the cationic PDMAEMA block but with different lengths of the PCL blocks. The block copolymers form cationic micelles in water which can adsorb to anionic surfaces such as silicon oxide and cellulose-model surfaces. After heat treatment, the contact angles of water on the treated surfaces increased significantly, and contact angles close to those of pure PCL were obtained for the block copolymers with longer PCL blocks. AFM force measurements showed a clear entangling behavior between the block copolymers and a PCL surface at about 60 °C, which is important for the formation of an adhesive interface in the final biocomposites. This demonstrates that this type of amphiphilic block copolymer can be used to improve interactions in biocomposites between anionic reinforcing materials such as cellulose-based fibers/fibrils and less polar matrices such as PCL.

  12. [THE TECHNOLOGY "CELL BLOCK" IN CYTOLOGICAL PRACTICE].

    Science.gov (United States)

    Volchenko, N N; Borisova, O V; Baranova, I B

    2015-08-01

    The article presents summary information concerning application of "cell block" technology in cytological practice. The possibilities of implementation of various modern techniques (immune cytochemnical analysis. FISH, CISH, polymerase chain reaction) with application of "cell block" method are demonstrated. The original results of study of "cell block" technology made with gelatin, AgarCyto and Shadon Cyoblock set are presented. The diagnostic effectiveness of "cell block" technology and common cytological smear and also immune cytochemical analysis on samples of "cell block" technology and fluid cytology were compared. Actually application of "cell block" technology is necessary for ensuring preservation of cell elements for subsequent immune cytochemical and molecular genetic analysis.

  13. Word Variant Identification in Old French

    Directory of Open Access Journals (Sweden)

    Peter Willett

    1997-01-01

    Full Text Available Increasing numbers of historical texts are available in machine-readable form, which retain the original spelling, which can be very different from the modern-day equivalents due to the natural evolution of a language, and because the concept of standardisation in spelling is comparatively modern. Among medieval vernacular writers, the same word could be spelled in different ways and the same author (or scribe might even use several alternative spellings in the same passage. Thus, we do not know,a priori, how many variant forms of a particular word there are in such texts, let alone what these variants might be. Searching on the modern equivalent, or even the commonest historical variant, of a particular word may thus fail to retrieve an appreciable number of occurrences unless the searcher already has an extensive knowledge of the language of the documents. Moreover, even specialist scholars may be unaware of some idiosyncratic variants. Here, we consider the use of computer methods to retrieve variant historical spellings.

  14. Identification of sequence variants influencing immunoglobulin levels.

    Science.gov (United States)

    Jonsson, Stefan; Sveinbjornsson, Gardar; de Lapuente Portilla, Aitzkoa Lopez; Swaminathan, Bhairavi; Plomp, Rosina; Dekkers, Gillian; Ajore, Ram; Ali, Mina; Bentlage, Arthur E H; Elmér, Evelina; Eyjolfsson, Gudmundur I; Gudjonsson, Sigurjon A; Gullberg, Urban; Gylfason, Arnaldur; Halldorsson, Bjarni V; Hansson, Markus; Holm, Hilma; Johansson, Åsa; Johnsson, Ellinor; Jonasdottir, Aslaug; Ludviksson, Bjorn R; Oddsson, Asmundur; Olafsson, Isleifur; Olafsson, Sigurgeir; Sigurdardottir, Olof; Sigurdsson, Asgeir; Stefansdottir, Lilja; Masson, Gisli; Sulem, Patrick; Wuhrer, Manfred; Wihlborg, Anna-Karin; Thorleifsson, Gudmar; Gudbjartsson, Daniel F; Thorsteinsdottir, Unnur; Vidarsson, Gestur; Jonsdottir, Ingileif; Nilsson, Björn; Stefansson, Kari

    2017-08-01

    Immunoglobulins are the effector molecules of the adaptive humoral immune system. In a genome-wide association study of 19,219 individuals, we found 38 new variants and replicated 5 known variants associating with IgA, IgG or IgM levels or with composite immunoglobulin traits, accounted for by 32 loci. Variants at these loci also affect the risk of autoimmune diseases and blood malignancies and influence blood cell development. Notable associations include a rare variant at RUNX3 decreasing IgA levels by shifting isoform proportions (rs188468174[C>T]: P = 8.3 × 10 -55 , β = -0.90 s.d.), a rare in-frame deletion in FCGR2B abolishing IgG binding to the encoded receptor (p.Asn106del: P = 4.2 × 10 -8 , β = 1.03 s.d.), four IGH locus variants influencing class switching, and ten new associations with the HLA region. Our results provide new insight into the regulation of humoral immunity.

  15. Visualizing the geography of genetic variants.

    Science.gov (United States)

    Marcus, Joseph H; Novembre, John

    2017-02-15

    One of the key characteristics of any genetic variant is its geographic distribution. The geographic distribution can shed light on where an allele first arose, what populations it has spread to, and in turn on how migration, genetic drift, and natural selection have acted. The geographic distribution of a genetic variant can also be of great utility for medical/clinical geneticists and collectively many genetic variants can reveal population structure. Here we develop an interactive visualization tool for rapidly displaying the geographic distribution of genetic variants. Through a REST API and dynamic front-end, the Geography of Genetic Variants (GGV) browser ( http://popgen.uchicago.edu/ggv/ ) provides maps of allele frequencies in populations distributed across the globe. GGV is implemented as a website ( http://popgen.uchicago.edu/ggv/ ) which employs an API to access frequency data ( http://popgen.uchicago.edu/freq_api/ ). Python and javascript source code for the website and the API are available at: http://github.com/NovembreLab/ggv/ and http://github.com/NovembreLab/ggv-api/ . jnovembre@uchicago.edu. Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press.

  16. Poly(phenylene ether Based Amphiphilic Block Copolymers

    Directory of Open Access Journals (Sweden)

    Edward N. Peters

    2017-09-01

    Full Text Available Polyphenylene ether (PPE telechelic macromonomers are unique hydrophobic polyols which have been used to prepare amphiphilic block copolymers. Various polymer compositions have been synthesized with hydrophilic blocks. Their macromolecular nature affords a range of structures including random, alternating, and di- and triblock copolymers. New macromolecular architectures can offer tailored property profiles for optimum performance. Besides reducing moisture uptake and making the polymer surface more hydrophobic, the PPE hydrophobic segment has good compatibility with polystyrene (polystyrene-philic. In general, the PPE contributes to the toughness, strength, and thermal performance. Hydrophilic segments go beyond their affinity for water. Improvements in the interfacial adhesion between polymers and polar substrates via hydrogen bonding and good compatibility with polyesters (polyester-philic have been exhibited. The heterogeneity of domains in these PPE based block copolymer offers important contributions to diverse applications.

  17. Cryptanalysis of SIMON Variants with Connections

    DEFF Research Database (Denmark)

    Alizadeh, Javad; Alkhzaimi, Hoda A.; Aref, Mohammad Reza

    2014-01-01

    SIMON is a family of 10 lightweight block ciphers published by Beaulieu et al. from the United States National Security Agency (NSA). A cipher in this family with K-bit key and N-bit block is called SIMONN/K. We present several linear characteristics for reduced-round SIMON32/64 that can be used...

  18. Mechanism of titania deposition into cylindrical poly(styrene-block-4 vinyl pyridine) block copolymer templates.

    Science.gov (United States)

    Lou, Qin; Chinthamanipeta, Pavan S; Shipp, Devon A

    2011-12-20

    A simple and effective way for TiO(2) to be deposited on silicon or indium tin oxide (ITO) substrates has been achieved by using a poly(styrene-block-4-vinyl pyridine) (PS-b-P4VP) block copolymer template. In particular, a mechanism for the formation of TiO(2) within the P4VP phase was developed. Within this model, the TiO(2) deposition occurs by swelling of the protonated P4VP segments followed by transport of Ti precursor, probably protonated Ti(OH)(4) given the low pH conditions used, into the swollen P4VP followed by condensation into TiO(2) during the heating/plasma etch processes. TiO(2) nanostructure morphology is affected by pH and deposition temperatures, because these parameters affect the degree of protonation of P4VP segments and diffusion of the titanium(IV) bis(ammonium lactato)dihydroxide (TALH) precursor into the film. A pH range of 2.1-2.5 for silicon substrates and pH = 2.1 for ITO substrates gave the narrower TiO(2) nanostructures distributions, and deposition at 70 °C gave TiO(2) nanostructures with more regular arrangements and smoother surface than those deposited at room temperature. The use of 1,4-diiodobutane as a P4VP cross-linking compound is demonstrated to be a critical parameter for maintaining good cylindrical surface morphology for both the block copolymer template and the TiO(2) nanostructures. © 2011 American Chemical Society

  19. Effect of sympathetic nerve block on acute inflammatory pain and hyperalgesia

    DEFF Research Database (Denmark)

    Pedersen, J L; Rung, G W; Kehlet, H

    1997-01-01

    . The duration and quality of blocks were evaluated by the sympatogalvanic skin response and skin temperature. Bilateral heat injuries were produced on the medial surfaces of the calves with a 50 x 25 mm thermode (47 degrees C, 7 min) 45 min after the blocks. Pain intensity induced by heat, pain thresholds....... METHODS: The study was made as a randomized, single blinded investigation, in which the volunteers served as their own controls. A lumbar sympathetic nerve block and a contralateral placebo block were performed in 24 persons by injecting 10 ml bupivacaine (0.5%) and 10 ml saline, respectively...... acute inflammatory pain or hyperalgesia after a heat injury in human skin....

  20. A framework for the definition of variants of high-level Petri nets

    DEFF Research Database (Denmark)

    Kindler, Ekkart; Petrucci, Laure

    2009-01-01

    analysis algorithms for symmetric nets. During the standardisation of high-level nets and some of their variations, it turned out that defining the legal data types and the operations on them is the most difficult part. In particular, these definitions become lengthy and mix Petri net specific issues...... with data-type specific issues, which often blocks the view for the really relevant parts. Even worse, supposedly simpler versions of high-level nets often are more difficult to define than high-level nets in general. This paper introduces the concepts and the mathematical tools to ease the definition...... of new variants and versions of high-level Petri nets: a framework for defining variants of high-level nets. The main ingredient of this framework is the concept of generators, which we recently introduced for formalising modular PNML, and the newly introduced concept of constructs....

  1. Genetic variants in toll-like receptors are not associated with rheumatoid arthritis susceptibility or anti-tumour necrosis factor treatment outcome

    DEFF Research Database (Denmark)

    Coenen, Marieke J H; Enevold, Christian; Barrera, Pilar

    2010-01-01

    Several studies point to a role of Toll-like receptors (TLRs) in the development of rheumatoid arthritis (RA). We investigated if genetic variants in TLR genes are associated with RA and response to tumour necrosis factor blocking (anti-TNF) medication....

  2. Genetics in psychiatry: common variant association studies

    Directory of Open Access Journals (Sweden)

    Buxbaum Joseph D

    2010-03-01

    Full Text Available Abstract Many psychiatric conditions and traits are associated with significant heritability. Genetic risk for psychiatric conditions encompass rare variants, identified due to major effect, as well as common variants, the latter analyzed by association analyses. We review guidelines for common variant association analyses, undertaking after assessing evidence of heritability. We highlight the importance of: suitably large sample sizes; an experimental design that controls for ancestry; careful data cleaning; correction for multiple testing; small P values for positive findings; assessment of effect size for positive findings; and, inclusion of an independent replication sample. We also note the importance of a critical discussion of any prior findings, biological follow-up where possible, and a means of accessing the raw data.

  3. Splicing variants of porcine synphilin-1

    DEFF Research Database (Denmark)

    Larsen, Knud Erik; Madsen, Lone Bruhn; Farajzadeh, Leila

    2015-01-01

    %) and to mouse (84%) synphilin-1. Three shorter transcript variants of the synphilin-1 gene were identified, all lacking one or more exons. SNCAIP transcripts were detected in most examined organs and tissues and the highest expression was found in brain tissues and lung. Conserved splicing variants and a novel...... splice form of synhilin-1 were found in this study. All synphilin-1 isoforms encoded by the identified transcript variants lack functional domains important for protein degradation....... with α-synuclein in LBs. The aim of this study was to isolate and characterize porcine synphilin-1 and isoforms hereof with the future perspective to use the pig as a model for Parkinson's disease. The porcine SNCAIP cDNA was cloned by reverse transcriptase PCR. The spatial expression of SNCAIP mRNA...

  4. Hemoglobin Variants: Biochemical Properties and Clinical Correlates

    Science.gov (United States)

    Thom, Christopher S.; Dickson, Claire F.; Gell, David A.; Weiss, Mitchell J.

    2013-01-01

    Diseases affecting hemoglobin synthesis and function are extremely common worldwide. More than 1000 naturally occurring human hemoglobin variants with single amino acid substitutions throughout the molecule have been discovered, mainly through their clinical and/or laboratory manifestations. These variants alter hemoglobin structure and biochemical properties with physiological effects ranging from insignificant to severe. Studies of these mutations in patients and in the laboratory have produced a wealth of information on hemoglobin biochemistry and biology with significant implications for hematology practice. More generally, landmark studies of hemoglobin performed over the past 60 years have established important paradigms for the disciplines of structural biology, genetics, biochemistry, and medicine. Here we review the major classes of hemoglobin variants, emphasizing general concepts and illustrative examples. PMID:23388674

  5. Traces of warping subsided tectonic blocks on Miranda, Enceladus, Titan

    Science.gov (United States)

    Kochemasov, G.

    2007-08-01

    Icy satellites of the outer Solar system have very large range of sizes - from kilometers to thousands of kilometers. Bodies less than 400-500 km across have normally irregular shapes , often presenting simple Plato's polyhedrons woven by standing inertiagravity waves (see an accompanying abstract of Kochemasov). Larger bodies with enhanced gravity normally are rounded off and have globular shapes but far from ideal spheres. This is due to warping action of inertia-gravity waves of various wavelengths origin of which is related to body movements in elliptical keplerian orbits with periodically changing accelerations (alternating accelerations cause periodically changing forces acting upon a body what means oscillations of its spheres in form of standing warping waves). The fundamental wave 1 and its first overtone wave 2 produce ubiquitous tectonic dichotomy - two segmental structure and tectonic sectoring superimposed on this dichotomy. Two kinds of tectonic blocks (segments and sectors) are formed: uplifted (+) and subsided (-). Uplifting means increasing planetary radius of blocks, subsiding - decreasing radius (as a sequence subsiding blocks diminishing their surfaces must be warped, folded, wrinkled; uplifting blocks increasing their surfaces tend to be deeply cracked, fallen apart). To level changing angular momenta of blocks subsided areas are filled with denser material than uplifted ones (one of the best examples is Earth with its oceanic basins filled with dense basalts and uplifted continents built of less dense on average andesitic material). Icy satellites follow the same rule. Their warped surfaces show differing chemistries or structures of constructive materials. Uplifted blocks are normally built with light (by color and density) water ice. Subsided blocks - depressions, "seas', "lakes", coronas - by somewhat denser material differing in color from water ice (very sharply - Iapetus, moderately - Europa, slightly - many saturnian satellites). A very

  6. Morphology evolution of PS-b-PDMS block copolymer and its hierarchical directed self-assembly on block copolymer templates

    DEFF Research Database (Denmark)

    Rasappa, Sozaraj; Schulte, Lars; Borah, Dipu

    2018-01-01

    Cylinder-forming polystyrene-block-polydimethylsiloxane (PS-b-PDMS, 27.2k-b-11.7k, SD39) block copolymer having a total molecular weight of 39 kg mol−1 was exploited to achieve in-plane morphologies of lines, dots and antidots. Brush-free self-assembly of the SD39 on silicon substrates was invest...... substrates provides a simplified method for surface nanopatterning, templated growth of nanomaterials and nanofabrication....... the pattern into the underlying substrate. Directed self-assembly and hierarchical directed self-assembly on block copolymer templates for confinement of dots was successfully demonstrated. The strategy for achieving multiple morphologies using one BCP by mere choice of the annealing solvents on unmodified...

  7. Blocking device especially for circulating pumps

    International Nuclear Information System (INIS)

    Susil, J.; Vychodil, V.; Lorenc, P.

    1976-01-01

    The claim of the invention is a blocking device which blocks reverse flow occurring after the shutdown of circulating pumps, namely in the operation of nuclear power plants or in pumps with a high delivery head. (F.M.)

  8. Demographic Data - MDC_BlockGroup

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — A polygon feature class of Miami-Dade County Census 2000 Block Groups. A census Block Group is a statistical subdivision of a census Tract consisting of a cluster of...

  9. Normal variants of skin in neonates

    Directory of Open Access Journals (Sweden)

    Kulkarni M

    1996-01-01

    Full Text Available 2221 consecutive live births taking place between March 1994 and February 1995 were evaluated for a minimum period of 5 days to note for the occurrence of various normal anatomical variants specially those of skin. Birth weight, gestational age, maternal age, socio-economic status and consanguinity were carefully recorded in all the cases. Mongolian spots (72%, Epstein pearls (43.8%, Milia (26.2% and Erythema toxicum (25.2%, were the common dermatological variants noted. Maturity of the babies and possibly genetic factors (consanguinity are important factors in their causation as ordered in our study.

  10. Variant profiling of evolving prokaryotic populations

    Directory of Open Access Journals (Sweden)

    Markus Zojer

    2017-02-01

    Full Text Available Genomic heterogeneity of bacterial species is observed and studied in experimental evolution experiments and clinical diagnostics, and occurs as micro-diversity of natural habitats. The challenge for genome research is to accurately capture this heterogeneity with the currently used short sequencing reads. Recent advances in NGS technologies improved the speed and coverage and thus allowed for deep sequencing of bacterial populations. This facilitates the quantitative assessment of genomic heterogeneity, including low frequency alleles or haplotypes. However, false positive variant predictions due to sequencing errors and mapping artifacts of short reads need to be prevented. We therefore created VarCap, a workflow for the reliable prediction of different types of variants even at low frequencies. In order to predict SNPs, InDels and structural variations, we evaluated the sensitivity and accuracy of different software tools using synthetic read data. The results suggested that the best sensitivity could be reached by a union of different tools, however at the price of increased false positives. We identified possible reasons for false predictions and used this knowledge to improve the accuracy by post-filtering the predicted variants according to properties such as frequency, coverage, genomic environment/localization and co-localization with other variants. We observed that best precision was achieved by using an intersection of at least two tools per variant. This resulted in the reliable prediction of variants above a minimum relative abundance of 2%. VarCap is designed for being routinely used within experimental evolution experiments or for clinical diagnostics. The detected variants are reported as frequencies within a VCF file and as a graphical overview of the distribution of the different variant/allele/haplotype frequencies. The source code of VarCap is available at https://github.com/ma2o/VarCap. In order to provide this workflow to

  11. Variants of Modeling Dwelling Market Value

    Directory of Open Access Journals (Sweden)

    Barańska Anna

    2014-10-01

    Full Text Available The object of this paper is to determine real estate market value on the basis of a multidimensional function model in different variants: A - directly from the model estimated on the basis of a big database, B - from the same model form, but estimated on the basis of a reduced database consisting of dwellings most similar to the estimated one, and C - based on modeled prices corrected by random correction, calculated from random deviations for dwellings most similar to the assessed one. In the framework of statistical inference procedures, the resulting comparison was carried out by parametric significance tests. They were applied to draw conclusions on the analyzed variants

  12. Maternal Neutralization-Resistant Virus Variants Do Not Predict Infant HIV Infection Risk.

    Science.gov (United States)

    Milligan, Caitlin; Omenda, Maxwel M; Chohan, Vrasha; Odem-Davis, Katherine; Richardson, Barbra A; Nduati, Ruth; Overbaugh, Julie

    2016-02-02

    Mother-to-child transmission (MTCT) of HIV provides a setting for studying immune correlates of protection. Neutralizing antibodies (NAbs) are suggested to contribute to a viral bottleneck during MTCT, but their role in blocking transmission is unclear, as studies comparing the NAb sensitivities of maternal viruses have yielded disparate results. We sought to determine whether transmitting mothers differ from nontransmitting mothers in the ability to neutralize individual autologous virus variants present at transmission. Ten transmitting and 10 nontransmitting HIV-infected mothers at high risk of MTCT were included in this study. Full-length HIV envelope genes (n = 100) were cloned from peripheral blood mononuclear cells obtained near transmission from transmitting mothers and at similar time points from nontransmitting mothers. Envelope clones were tested as pseudoviruses against contemporaneous, autologous maternal plasma in neutralization assays. The association between transmission and the log2 50% inhibitory concentration (IC50) for multiple virus variants per mother was estimated by using logistic regression with clustered standard errors. t tests were used to compare proportions of neutralization-resistant viruses. Overall, transmitting mothers had a median IC50 of 317 (interquartile range [IQR], 202 to 521), and nontransmitting mothers had a median IC50 of 243 (IQR, 95 to 594). Transmission risk was not significantly associated with autologous NAb activity (odds ratio, 1.25; P = 0.3). Compared to nontransmitting mothers, transmitting mothers had similar numbers of or fewer neutralization-resistant virus variants, depending on the IC50 neutralization resistance cutoff. In conclusion, HIV-infected mothers harbor mostly neutralization-sensitive viruses, although resistant variants were detected in both transmitting and nontransmitting mothers. These results suggest that MTCT during the breastfeeding period is not driven solely by the presence of maternal

  13. Effect of concrete block weight and wall height on electromyographic activity and heart rate of masons.

    Science.gov (United States)

    Anton, D; Rosecrance, J C; Gerr, F; Merlino, L A; Cook, T M

    2005-08-15

    Work-related musculoskeletal disorders (MSDs) are common among construction workers, such as masons. Few interventions are available to reduce masons' exposure to heavy lifting, a risk factor for MSDs. The purpose of this study was to determine whether one such intervention, the use of light-weight concrete blocks (LWBs), reduces physiological loads compared to standard-weight blocks (SWBs). Using a repeated measures design, 21 masons each constructed two 32-block walls, seven courses (rows) high, entirely of either SWBs or LWBs. Surface electromyography (EMG), from arm and back muscles, and heart rate was sampled. For certain muscles, EMG amplitudes were slightly lower when masons were laying LWBs compared to SWBs. Upper back and forearm extensor EMG amplitudes were greater for the higher wall courses for both block weights. There were no significant differences in heart rate between the two blocks. Interventions that address block weight and course height may be effective for masons.

  14. Used, Blocking and Sleeping Patents

    DEFF Research Database (Denmark)

    Torrisi, Salvatore; Gambardella, Alfonso; Giuri, Paola

    2016-01-01

    patents are being utilized. A substantial share of patents is neither used internally nor for market transactions, which confirms the importance of strategic patenting and inefficiency in the management of intellectual property. We investigate different types of unused patents—unused blocking patents...... and sleeping patents. We also examine the association between used and unused patents and their characteristics such as family size, scope, generality and overlapping claims, technology area, type of applicant, and the competitive environment from where these patents originate. We discuss our results...

  15. Large block test status report

    International Nuclear Information System (INIS)

    Wilder, D.G.; Lin, W.; Blair, S.C.

    1997-01-01

    This report is intended to serve as a status report, which essentially transmits the data that have been collected to date on the Large Block Test (LBT). The analyses of data will be performed during FY98, and then a complete report will be prepared. This status report includes introductory material that is not needed merely to transmit data but is available at this time and therefore included. As such, this status report will serve as the template for the future report, and the information is thus preserved

  16. Two innovative solutions based on fibre concrete blocks designed for building substructure

    Science.gov (United States)

    Pazderka, J.; Hájek, P.

    2017-09-01

    Using of fibers in a high-strength concrete allows reduction of the dimensions of small precast concrete elements, which opens up new ways of solution for traditional construction details in buildings. The paper presents two innovative technical solutions for building substructure: The special shaped plinth block from fibre concrete and the fibre concrete elements for new technical solution of ventilated floor. The main advantages of plinth block from fibre concrete blocks (compared with standard plinth solutions) is: easier and faster assembly, higher durability and thanks to the air cavity between the vertical part of the block, the building substructure reduced moisture level of structures under the waterproofing layer and a comprehensive solution to the final surface of building plinth as well as the surface of adjacent terrain. The ventilated floor based on fibre concrete precast blocks is an attractive structural alternative for tackling the problem of increased moisture in masonry in older buildings, lacking a functional waterproof layer in the substructure.

  17. Micellization and Dynamics of a Block Copolymer

    DEFF Research Database (Denmark)

    Hvidt, Søren

    2006-01-01

    Triblock copolymers of the type EPE, where E and P denote ethylene oxide and propylene oxide blocks, respectively, are industrially important copolymers often called Pluronics or Poloxamers. EPE copolymers form micelles with a core of P blocks and different micellar shapes depending on block leng...

  18. 31 CFR 515.319 - Blocked account.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Blocked account. 515.319 Section 515... § 515.319 Blocked account. The term blocked account shall mean an account in which any designated national has an interest, with respect to which account payments, transfers or withdrawals or other...

  19. 31 CFR 500.319 - Blocked account.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Blocked account. 500.319 Section 500... § 500.319 Blocked account. The term blocked account shall mean an account in which any designated national has an interest, with respect to which account payments, transfers or withdrawals of other...

  20. Bullet-Block Science Video Puzzle

    Science.gov (United States)

    Shakur, Asif

    2015-01-01

    A science video blog, which has gone viral, shows a wooden block shot by a vertically aimed rifle. The video shows that the block hit dead center goes exactly as high as the one shot off-center. (Fig. 1). The puzzle is that the block shot off-center carries rotational kinetic energy in addition to the gravitational potential energy. This leads a…

  1. 21 CFR 882.5070 - Bite block.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Bite block. 882.5070 Section 882.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Therapeutic Devices § 882.5070 Bite block. (a) Identification. A bite block...

  2. Functional consequences of AXL sequence variants in hypogonadotropic hypogonadism.

    Science.gov (United States)

    Salian-Mehta, S; Xu, M; Knox, A J; Plummer, L; Slavov, D; Taylor, M; Bevers, S; Hodges, R S; Crowley, W F; Wierman, M E

    2014-04-01

    Prior studies showed that Axl /Tyro3 null mice have delayed first estrus and abnormal cyclicity due to developmental defects in GnRH neuron migration and survival. The objective of the study was to test whether the absence of Axl would alter reproductive function in mice and that mutations in AXL are present in patients with Kallmann syndrome (KS) or normosmic idiopathic hypogonadotropic hypogonadism (nIHH). The sexual maturation of Axl null mice was examined. The coding region of AXL was sequenced in 104 unrelated, carefully phenotyped KS or nIHH subjects. Frequency of mutations was compared with other causes of GnRH deficiency. Functional assays were performed on the detected mutations. Axl null mice demonstrated delay in first estrus and the interval between vaginal opening and first estrus. Three missense AXL mutations (p.L50F, p.S202C, and p.Q361P) and one intronic variant 6 bp upstream from the start of exon 5 (c.586-6 C>T) were identified in two KS and 2 two nIHH subjects. Comparison of the frequencies of AXL mutations with other putative causes of idiopathic hypogonadotropic hypogonadism confirmed they are rare variants. Testing of the c.586-6 C>T mutation revealed no abnormal splicing. Surface plasmon resonance analysis of the p.L50F, p.S202C, and p.Q361P mutations showed no altered Gas6 ligand binding. In contrast, GT1-7 GnRH neuronal cells expressing p.S202C or p.Q361P demonstrated defective ligand dependent receptor processing and importantly aberrant neuronal migration. In addition, the p.Q361P showed defective ligand independent chemotaxis. Functional consequences of AXL sequence variants in patients with idiopathic hypogonadotropic hypogonadism support the importance of AXL and the Tyro3, Axl, Mer (TAM) family in reproductive development.

  3. Expression of CD44 variants in human inflammatory synovitis

    Energy Technology Data Exchange (ETDEWEB)

    Hale, L.P. [Duke Univ. Medical Center, Durham, NC (United States); Haynes, B.F.; McCachren, S. [Duke Univ. Arthritis Center, Durham, NC (United States)

    1995-11-01

    The cell surface hyaluronate receptor CD44 has previously been shown to have immunomodulatory activity and to be upregulated in inflammatory synovitis. Since these findings were reported, the genomic structure of CD44 has been delineated, and multiple splice variants have been described. Therefore, we determined which CD44 variant exons are present during inflammatory synovitis by a combination of Northern blot analysis and reverse transcription followed by polymerase chain reaction amplification of synovial RNA. Immunohistochemical staining was used to define the sites of expression of individual v6 and v9 exons in synovial tissue. The standard (S) or hematopoietic isoform, CD44S, was the predominant form of CD44 expressed in synovium and was expressed by most cell types. Other isoforms, containing alternatively spliced exons in the proximal extracellular domain, were found by RT-PCR, but at lower levels than CD44S. The second most prevalent form was CD44E, which has an insertion of three exons (v8-v10) in the proximal extracellular domain. Immunohistochemical studies showed that reactivity with v9-specific antibodies was primarily in macrophages, particularly those in the synovial lining layer. CD44 exon v6, previously reported to be important in immune activation and in epithelial tumor metastasis, was also expressed in synovial lining cells and in occasional synovial interstitial cells. The presence of CD44 variants containing v9 in rheumatoid synovial macrophages may be important in the adhesion and activation of mononuclear phagocytes in the synovium and, thus, may be a target for novel antiinflammatory therapies in the future. The role of CD44 isoforms in cellular adhesion, immune activation, and joint erosion in inflammatory synovitis deserves further study. 7 figs., 2 tabs., 56 refs.

  4. Three-dimensional Reconstruction of Block Shape Irregularity and its Effects on Block Impacts Using an Energy-Based Approach

    Science.gov (United States)

    Zhang, Yulong; Liu, Zaobao; Shi, Chong; Shao, Jianfu

    2018-04-01

    This study is devoted to three-dimensional modeling of small falling rocks in block impact analysis in energy view using the particle flow method. The restitution coefficient of rockfall collision is introduced from the energy consumption mechanism to describe rockfall-impacting properties. Three-dimensional reconstruction of falling block is conducted with the help of spherical harmonic functions that have satisfactory mathematical properties such as orthogonality and rotation invariance. Numerical modeling of the block impact to the bedrock is analyzed with both the sphere-simplified model and the 3D reconstructed model. Comparisons of the obtained results suggest that the 3D reconstructed model is advantageous in considering the combination effects of rockfall velocity and rotations during colliding process. Verification of the modeling is carried out with the results obtained from other experiments. In addition, the effects of rockfall morphology, surface characteristics, velocity, and volume, colliding damping and relative angle are investigated. A three-dimensional reconstruction modulus of falling blocks is to be developed and incorporated into the rockfall simulation tools in order to extend the modeling results at block scale to slope scale.

  5. Time delay control of power converters: Mixed frame and stationary-frame variants

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Loh, P.C.; Tang, Y.

    2008-01-01

    the positive and negative-sequence fundamental currents, which are known to directly influence the flow of active and reactive power in most energy conversion systems. Moreover, for the tracking or compensation of harmonics, the controllers include a time delay control path in either the synchronous...... simple implementation using mainly delay blocks, were physically tested with a digitally controlled commercial converter system....... an unfiltered angle or by using its equivalent frequency-shifted variant, the tracking abilities of both controllers can also be shown to remain undisturbed even if a distorted grid or back-emf source is intentionally connected to the system. These described performance features, together with the controller...

  6. Prediction of Service Life for Assembly with Time-variant Deviation

    Science.gov (United States)

    Zeng, Wenhui; Rao, Yunqing; Long, Chenxi; Wang, Peng

    2017-06-01

    During operation, the time-variant deviations, such as deformation, thermal expansion, friction and wear always occur and affect the mechanical performance and service life of assembly. In this paper, a methodology for the prediction of service life for assembly with time-variant deviations is proposed. Firstly, based on the modified Unified Jacobian-Torsor model and Monte Carlo simulation, according to the distribution the geometric and dimension tolerances are randomly generated to limit the variations of surface of part. Secondly, the deformations caused by load and thermal expansion are obtained by finite element analysis, and considering the friction and wear, the prediction model of service life is constructed subject to the constraints. At last, an application is given to illustrate the prediction model, and the influences of time-variant deviations on the assembly deviation and service life are analyzed.

  7. Isostatic compression of buffer blocks. Middle scale

    International Nuclear Information System (INIS)

    Ritola, J.; Pyy, E.

    2012-01-01

    Manufacturing of buffer components using isostatic compression method has been studied in small scale in 2008 (Laaksonen 2010). These tests included manufacturing of buffer blocks using different bentonite materials and different compression pressures. Isostatic mould technology was also tested, along with different methods to fill the mould, such as vibration and partial vacuum, as well as a stepwise compression of the blocks. The development of manufacturing techniques has continued with small-scale (30 %) blocks (diameter 600 mm) in 2009. This was done in a separate project: Isostatic compression, manufacturing and testing of small scale (D = 600 mm) buffer blocks. The research on the isostatic compression method continued in 2010 in a project aimed to test and examine the isostatic manufacturing process of buffer blocks at 70 % scale (block diameter 1200 to 1300 mm), and the aim was to continue in 2011 with full-scale blocks (diameter 1700 mm). A total of nine bentonite blocks were manufactured at 70 % scale, of which four were ring-shaped and the rest were cylindrical. It is currently not possible to manufacture full-scale blocks, because there is no sufficiently large isostatic press available. However, such a compression unit is expected to be possible to use in the near future. The test results of bentonite blocks, produced with an isostatic pressing method at different presses and at different sizes, suggest that the technical characteristics, for example bulk density and strength values, are somewhat independent of the size of the block, and that the blocks have fairly homogenous characteristics. Water content and compression pressure are the two most important properties determining the characteristics of the compressed blocks. By adjusting these two properties it is fairly easy to produce blocks at a desired density. The commonly used compression pressure in the manufacturing of bentonite blocks is 100 MPa, which compresses bentonite to approximately

  8. Coastal protection using topological interlocking blocks

    Science.gov (United States)

    Pasternak, Elena; Dyskin, Arcady; Pattiaratchi, Charitha; Pelinovsky, Efim

    2013-04-01

    The coastal protection systems mainly rely on the self-weight of armour blocks to ensure its stability. We propose a system of interlocking armour blocks, which form plate-shape assemblies. The shape and the position of the blocks are chosen in such a way as to impose kinematic constraints that prevent the blocks from being removed from the assembly. The topological interlocking shapes include simple convex blocks such as platonic solids, the most practical being tetrahedra, cubes and octahedra. Another class of topological interlocking blocks is so-called osteomorphic blocks, which form plate-like assemblies tolerant to random block removal (almost 25% of blocks need to be removed for the assembly to loose integrity). Both classes require peripheral constraint, which can be provided either by the weight of the blocks or post-tensioned internal cables. The interlocking assemblies provide increased stability because lifting one block involves lifting (and bending) the whole assembly. We model the effect of interlocking by introducing an equivalent additional self-weight of the armour blocks. This additional self-weight is proportional to the critical pressure needed to cause bending of the interlocking assembly when it loses stability. Using beam approximation we find an equivalent stability coefficient for interlocking. It is found to be greater than the stability coefficient of a structure with similar blocks without interlocking. In the case when the peripheral constraint is provided by the weight of the blocks and for the slope angle of 45o, the effective stability coefficient for a structure of 100 blocks is 33% higher than the one for a similar structure without interlocking. Further increase in the stability coefficient can be reached by a specially constructed peripheral constraint system, for instance by using post-tension cables.

  9. Isostatic compression of buffer blocks. Middle scale

    Energy Technology Data Exchange (ETDEWEB)

    Ritola, J.; Pyy, E. [VTT Technical Research Centre of Finland, Espoo (Finland)

    2012-01-15

    Manufacturing of buffer components using isostatic compression method has been studied in small scale in 2008 (Laaksonen 2010). These tests included manufacturing of buffer blocks using different bentonite materials and different compression pressures. Isostatic mould technology was also tested, along with different methods to fill the mould, such as vibration and partial vacuum, as well as a stepwise compression of the blocks. The development of manufacturing techniques has continued with small-scale (30 %) blocks (diameter 600 mm) in 2009. This was done in a separate project: Isostatic compression, manufacturing and testing of small scale (D = 600 mm) buffer blocks. The research on the isostatic compression method continued in 2010 in a project aimed to test and examine the isostatic manufacturing process of buffer blocks at 70 % scale (block diameter 1200 to 1300 mm), and the aim was to continue in 2011 with full-scale blocks (diameter 1700 mm). A total of nine bentonite blocks were manufactured at 70 % scale, of which four were ring-shaped and the rest were cylindrical. It is currently not possible to manufacture full-scale blocks, because there is no sufficiently large isostatic press available. However, such a compression unit is expected to be possible to use in the near future. The test results of bentonite blocks, produced with an isostatic pressing method at different presses and at different sizes, suggest that the technical characteristics, for example bulk density and strength values, are somewhat independent of the size of the block, and that the blocks have fairly homogenous characteristics. Water content and compression pressure are the two most important properties determining the characteristics of the compressed blocks. By adjusting these two properties it is fairly easy to produce blocks at a desired density. The commonly used compression pressure in the manufacturing of bentonite blocks is 100 MPa, which compresses bentonite to approximately

  10. Functional analysis of human cytochrome P450 21A2 variants involved in congenital adrenal hyperplasia

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Chunxue; Pallan, Pradeep S.; Zhang, Wei; Lei, Li; Yoshimoto, Francis K.; Waterman, Michael R.; Egli, Martin; Guengerich, F. Peter (Vanderbilt-MED)

    2017-05-24

    Cytochrome P450 (P450, CYP) 21A2 is the major steroid 21-hydroxylase, converting progesterone to 11-deoxycorticosterone and 17α-hydroxyprogesterone (17α-OH-progesterone) to 11-deoxycortisol. More than 100 CYP21A2 variants give rise to congenital adrenal hyperplasia (CAH). We previously reported a structure of WT human P450 21A2 with bound progesterone and now present a structure bound to the other substrate (17α-OH-progesterone). We found that the 17α-OH-progesterone- and progesterone-bound complex structures are highly similar, with only some minor differences in surface loop regions. Twelve P450 21A2 variants associated with either salt-wasting or nonclassical forms of CAH were expressed, purified, and analyzed. The catalytic activities of these 12 variants ranged from 0.00009% to 30% of WT P450 21A2 and the extent of heme incorporation from 10% to 95% of the WT. Substrate dissociation constants (Ks) for four variants were 37–13,000-fold higher than for WT P450 21A2. Cytochrome b5, which augments several P450 activities, inhibited P450 21A2 activity. Similar to the WT enzyme, high noncompetitive intermolecular kinetic deuterium isotope effects (≥ 5.5) were observed for all six P450 21A2 variants examined for 21-hydroxylation of 21-d3-progesterone, indicating that C–H bond breaking is a rate-limiting step over a 104-fold range of catalytic efficiency. Using UV-visible and CD spectroscopy, we found that P450 21A2 thermal stability assessed in bacterial cells and with purified enzymes differed among salt-wasting- and nonclassical-associated variants, but these differences did not correlate with catalytic activity. Our in-depth investigation of CAH-associated P450 21A2 variants reveals critical insight into the effects of disease-causing mutations on this important enzyme.

  11. Randomized Block Cubic Newton Method

    KAUST Repository

    Doikov, Nikita

    2018-02-12

    We study the problem of minimizing the sum of three convex functions: a differentiable, twice-differentiable and a non-smooth term in a high dimensional setting. To this effect we propose and analyze a randomized block cubic Newton (RBCN) method, which in each iteration builds a model of the objective function formed as the sum of the natural models of its three components: a linear model with a quadratic regularizer for the differentiable term, a quadratic model with a cubic regularizer for the twice differentiable term, and perfect (proximal) model for the nonsmooth term. Our method in each iteration minimizes the model over a random subset of blocks of the search variable. RBCN is the first algorithm with these properties, generalizing several existing methods, matching the best known bounds in all special cases. We establish ${\\\\cal O}(1/\\\\epsilon)$, ${\\\\cal O}(1/\\\\sqrt{\\\\epsilon})$ and ${\\\\cal O}(\\\\log (1/\\\\epsilon))$ rates under different assumptions on the component functions. Lastly, we show numerically that our method outperforms the state-of-the-art on a variety of machine learning problems, including cubically regularized least-squares, logistic regression with constraints, and Poisson regression.

  12. Silver-enhanced block copolymer membranes with biocidal activity

    KAUST Repository

    Madhavan, Poornima

    2014-11-12

    Silver nanoparticles were deposited on the surface and pore walls of block copolymer membranes with highly ordered pore structure. Pyridine blocks constitute the pore surfaces, complexing silver ions and promoting a homogeneous distribution. Nanoparticles were then formed by reduction with sodium borohydride. The morphology varied with the preparation conditions (pH and silver ion concentration), as confirmed by field emission scanning and transmission electron microscopy. Silver has a strong biocide activity, which for membranes can bring the advantage of minimizing the growth of bacteria and formation of biofilm. The membranes with nanoparticles prepared under different pH values and ion concentrations were incubated with Pseudomonas aeruginosa and compared with the control. The strongest biocidal activity was achieved with membranes containing membranes prepared under pH 9. Under these conditions, the best distribution with small particle size was observed by microscopy.

  13. Novel block, graft and random copolymers for biomedical applications

    DEFF Research Database (Denmark)

    Javakhishvili, Irakli; Jankova Atanasova, Katja; Tanaka, Masaru

    Despite the simple structure, poly(2-methoxyethyl acrylate) (PMEA) shows excellent blood compatibility [1]. Both the freezing-bound water (intermediate water: preventing the biocomponents from directly contacting the polymer surface) and non-freezing water on the polymer surface play important ro...... copolymers with MMA [4] utilizing ATRP. Here we present other block, graft and random copolymers of MEA intended for biomedical applications. These macromolecular architectures have been constructed by employing controlled radical polymerization methods such as RAFT and ATRP....... roles for this [2]. An artificial lung (oxygenator), already in use, is coated with high MW PMEA prepared by radical polymerization with AIBN [2]. To broaden the possibilities for designing biomedical devices [3] and inspired from these findings we first prepared homo polymers of MEA and their block...

  14. Guidelines for investigating causality of sequence variants in human disease

    Science.gov (United States)

    MacArthur, D. G.; Manolio, T. A.; Dimmock, D. P.; Rehm, H. L.; Shendure, J.; Abecasis, G. R.; Adams, D. R.; Altman, R. B.; Antonarakis, S. E.; Ashley, E. A.; Barrett, J. C.; Biesecker, L. G.; Conrad, D. F.; Cooper, G. M.; Cox, N. J.; Daly, M. J.; Gerstein, M. B.; Goldstein, D. B.; Hirschhorn, J. N.; Leal, S. M.; Pennacchio, L. A.; Stamatoyannopoulos, J. A.; Sunyaev, S. R.; Valle, D.; Voight, B. F.; Winckler, W.; Gunter, C.

    2014-01-01

    The discovery of rare genetic variants is accelerating, and clear guidelines for distinguishing disease-causing sequence variants from the many potentially functional variants present in any human genome are urgently needed. Without rigorous standards we risk an acceleration of false-positive reports of causality, which would impede the translation of genomic research findings into the clinical diagnostic setting and hinder biological understanding of disease. Here we discuss the key challenges of assessing sequence variants in human disease, integrating both gene-level and variant-level support for causality. We propose guidelines for summarizing confidence in variant pathogenicity and highlight several areas that require further resource development. PMID:24759409

  15. The glass block site radionuclide migration study

    International Nuclear Information System (INIS)

    Killey, R.W.D.; Champ, D.R.

    1990-01-01

    In 1960 25 nepheline syenite glass blocks containing 14 TBq of mixed fission products in 50 kg of glass were placed below the water table in a shallow sand aquifer at Chalk River Laboratories. Experimental studies undertaken at the site since 1960 have included detailed mapping of the plume of 90 Sr in 1963, 1966 and 1971. Mathematical modeling studies have employed the radiostrontium plume data in determining the split between ion exchange and chemisorption of 90 Sr, and in obtaining reaction rate data for chemisorption. The distribution of 137 Cs on downgradient soils was mapped in 1963 and 1979. An extended plume of low-level 137 Cs contamination observed in the 1979 study prompted an investigation of the role of particulate materials in radionuclide transport. IN 1983, large volume groundwater sampling and separation of cationic, anionic, and neutral dissolved species, as well as particulates, detected anionic and cationic dissolved europium isotopes (154 and 155), and again encountered particulate 137 Cs. A variety of investigations of cesium and strontium sorption have provided a data base on sediment mineralogy, particle surface features, and information on sorption sites and processes. The year 1990 saw the inauguration of a three-year program to update investigations of radionuclide release, transport, and sorption at the glass block site. The first stage of the program has been a detailed definition and simulation of the hydrogeologic setting. Plume mapping and aqueous speciation studies are in progress. This paper summarizes past investigations, reviews the status of the current program, and discusses components of future studies, including investigations of sediment sorption mechanisms. (Author) (17 refs., 8 figs.)

  16. Characterization of splice variants of the genes encoding human mitochondrial HMG-CoA lyase and HMG-CoA synthase, the main enzymes of the ketogenesis pathway.

    Science.gov (United States)

    Puisac, Beatriz; Ramos, Mónica; Arnedo, María; Menao, Sebastián; Gil-Rodríguez, María Concepción; Teresa-Rodrigo, María Esperanza; Pié, Angeles; de Karam, Juan Carlos; Wesselink, Jan-Jaap; Giménez, Ignacio; Ramos, Feliciano J; Casals, Nuria; Gómez-Puertas, Paulino; Hegardt, Fausto G; Pié, Juan

    2012-04-01

    The genes HMGCS2 and HMGCL encode the two main enzymes for ketone-body synthesis, mitochondrial HMG-CoA synthase and HMG-CoA lyase. Here, we identify and describe possible splice variants of these genes in human tissues. We detected an alternative transcript of HMGCS2 carrying a deletion of exon 4, and two alternative transcripts of HMGCL with deletions of exons 5 and 6, and exons 5, 6 and 7, respectively. All splice variants maintained the reading frame. However, Western blot studies and overexpression measurements in eukaryotic or prokaryotic cell models did not reveal HL or mHS protein variants. Both genes showed a similar distribution of the inactive variants in different tissues. Surprisingly, the highest percentages were found in tissues where almost no ketone bodies are synthesized: heart, skeletal muscle and brain. Our results suggest that alternative splicing might coordinately block the two main enzymes of ketogenesis in specific human tissues.

  17. Reduced Penetrance and Variable Expression of SCN5A Mutations and the Importance of Co-inherited Genetic Variants: Case Report and Review of the Literature

    Directory of Open Access Journals (Sweden)

    T. Robyns, MD.

    2014-05-01

    Full Text Available Mutations in the SCN5A gene are responsible for multiple phenotypical presentations including Brugada syndrome, long QT syndrome, progressive familial heart block, sick sinus syndrome, dilated cardiomyopathy, lone atrial fibrillation and multiple overlap syndromes. These different phenotypic expressions of a mutation in a single gene can be explained by variable expression and reduced penetrance. One of the possible explanations of these phenomena is the co-inheritance of genetic variants. We describe a family where the individuals exhibit a compound heterozygosity in the SCN5A gene including a mutation (R1632H and a new variant (M858L. Individuals with both the mutation and new variant present with a more severe phenotype including spontaneous atrial tachyarrhythmia at young age. We give an overview of the different phenotypes of "SCN5A disease" and discuss the importance of co-inherited genetic variants in the expression of SCN5A disease.

  18. ALS insertion device block measurement and inspection

    International Nuclear Information System (INIS)

    Marks, S.; Carrieri, J.; Cook, C.; Hassenzahl, W.V.; Hoyer, E.; Plate, D.

    1991-05-01

    The performance specifications for ALS insertion devices require detailed knowledge and strict control of the Nd-Fe-B permanent magnet blocks incorporated in these devices. This paper describes the measurement and inspection apparatus and the procedures designed to qualify and characterize these blocks. A detailed description of a new, automated Helmholtz coil facility for measurement of the three components of magnetic moment is included. Physical block inspection and magnetic moment measurement procedures are described. Together they provide a basis for qualifying blocks and for specifying placement of blocks within an insertion devices' magnetic structures. 1 ref., 4 figs

  19. Adaptive motion compensation without blocking artifacts

    Science.gov (United States)

    Terriberry, Timothy B.

    2015-03-01

    The Block Matching Algorithms used in most popular video codec standards introduce blocking artifacts which must be removed via residual coding or deblocking filters. Alternative transform stages that do not cause blocking artifacts, such as lapped transforms or wavelets, require motion compensation methods that do not produce blocking artifacts, since they are expensive to remove. We design a new Overlapped Block Motion Compensation (OBMC) scheme that avoids these artifacts while allowing adaptive blending window sizes. This has the potential to show significant visual quality improvements over traditional OBMC.

  20. Probabilistic Transcriptome Assembly and Variant Graph Genotyping

    DEFF Research Database (Denmark)

    Sibbesen, Jonas Andreas

    that this approach outperforms existing state-of-the-art methods measured using sensitivity and precision on both simulated and real data. The second is a novel probabilistic method that uses exact alignment of k-mers to a set of variants graphs to provide unbiased estimates of genotypes in a population...

  1. HLogo: a parallel Haskell variant of Netlogo

    NARCIS (Netherlands)

    N. Bezirgiannis (Nikolaos); Prasetya, I.S.W.B.; Sakellariou, I.

    2016-01-01

    textabstractAgent-based Modeling (ABM) has become quite popular to the simulation community for its usability and wide area of applicability. However, speed is not usually a trait that ABM tools are characterized of attaining. This paper presents HLogo, a parallel variant of the NetLogo ABM

  2. Mining Process Variants: Goals and Issues

    NARCIS (Netherlands)

    Li, J.; Li, C.; Reichert, M.U.; Wombacher, Andreas

    Recently, Process-Aware Information Systems (PAIS) were introduced, which allow for dynamic process and service changes. This, in turn, has led to a large number of process model variants, which are difficult to maintain and expensive to configure. This paper deals with goals and issues related to

  3. XVCL: XML-based Variant Configuration Language

    DEFF Research Database (Denmark)

    Jarzabek, Stan; Basset, Paul; Zhang, Hongyu

    2003-01-01

    XVCL (XML-based Variant Configuration Language) is a meta-programming technique and tool that provides effective reuse mechanisms. XVCL is an open source software developed at the National University of Singapore. Being a modern and versatile version of Bassett's frames, a technology that has...

  4. Analysis of the energy development variants

    International Nuclear Information System (INIS)

    Tsvetanov, P.

    1990-01-01

    Analysis of the variants of energy development is made as the third stage of a procedure of energy-economy interrelations dynamics study, the other two stages being the scenarios description and the formulation of the variants. This stage includes a research on the dimensions and the dynamics of the resources demands, the general features and the trends of the national energy development. There is a presentation of a comparative analysis of the variants in terms of economic indices and energy values, computed by the model IMPACT-B. A resource evaluation of the development variants is given in terms of investments, requirements (direct, indirect and total) and limited national resources demands of the energy system. The trends of the national energy development discussed are: trends characterizing the changes in the structure of the energy consumption, resulting from changes in the economy; trends of the energy system impact on the productivity of labor; general trends of the proportionality in the industrial, the household and services sector development. 16 refs., 16 figs., 4 tabs. (R.Ts.)

  5. Report of a rare anatomic variant

    DEFF Research Database (Denmark)

    De Brucker, Y; Ilsen, B; Muylaert, C

    2015-01-01

    We report the CT findings in a case of partial anomalous pulmonary venous return (PAPVR) from the left upper lobe in an adult. PAPVR is an anatomic variant in which one to three pulmonary veins drain into the right atrium or its tributaries, rather than into the left atrium. This results in a lef...

  6. New genetic variants associated with prostate cancer

    Science.gov (United States)

    Researchers have newly identified 23 common genetic variants -- one-letter changes in DNA known as single-nucleotide polymorphisms or SNPs -- that are associated with risk of prostate cancer. These results come from an analysis of more than 10 million SNP

  7. Genetic variants influencing phenotypic variance heterogeneity.

    Science.gov (United States)

    Ek, Weronica E; Rask-Andersen, Mathias; Karlsson, Torgny; Enroth, Stefan; Gyllensten, Ulf; Johansson, Åsa

    2018-03-01

    Most genetic studies identify genetic variants associated with disease risk or with the mean value of a quantitative trait. More rarely, genetic variants associated with variance heterogeneity are considered. In this study, we have identified such variance single-nucleotide polymorphisms (vSNPs) and examined if these represent biological gene × gene or gene × environment interactions or statistical artifacts caused by multiple linked genetic variants influencing the same phenotype. We have performed a genome-wide study, to identify vSNPs associated with variance heterogeneity in DNA methylation levels. Genotype data from over 10 million single-nucleotide polymorphisms (SNPs), and DNA methylation levels at over 430 000 CpG sites, were analyzed in 729 individuals. We identified vSNPs for 7195 CpG sites (P mean DNA methylation levels. We further showed that variance heterogeneity between genotypes mainly represents additional, often rare, SNPs in linkage disequilibrium (LD) with the respective vSNP and for some vSNPs, multiple low frequency variants co-segregating with one of the vSNP alleles. Therefore, our results suggest that variance heterogeneity of DNA methylation mainly represents phenotypic effects by multiple SNPs, rather than biological interactions. Such effects may also be important for interpreting variance heterogeneity of more complex clinical phenotypes.

  8. Apolipoprotein gene variants and susceptibility to essential ...

    African Journals Online (AJOL)

    Apolipoprotein gene variants and susceptibility to essential hypertension in Cameroon. ... Results: Whereas advanced age, SBP, DBP, lack of exercise and family history constituted risk factors of EH, sex, body mass index (BMI), Fasting blood sugar (FBS), lipid profile, smoking, excessive alcohol consumption did not.

  9. Developing consistent pronunciation models for phonemic variants

    CSIR Research Space (South Africa)

    Davel, M

    2006-09-01

    Full Text Available from a lexicon containing variants. In this paper we (the authors) address both these issues by creating ‘pseudo-phonemes’ associated with sets of ‘generation restriction rules’ to model those pronunciations that are consistently realised as two or more...

  10. Extracting pronunciation rules for phonemic variants

    CSIR Research Space (South Africa)

    Davel, M

    2006-04-01

    Full Text Available that occur in the training lexicon. In this paper authors propose an approach for the incorporation of phonemic variants in a typical instance based learning algorithm, Default and Refine. Authors investigate the use of a combined ‘pseudo-phoneme’ associated...

  11. Variants of the left aortic arch branches

    African Journals Online (AJOL)

    Type C (Courtesy of Rutherford. Vascular. Surgery. 4th ed. Philadelphia: Saunders, 19954). Fig. 1. Type A. Abstract. The normal aorta has three branches from its arch, but variations in this pattern are not uncommon. Our interest was to correlate the docu- mented statistics to the variants observed in our patients. This was.

  12. DROUGHT RESISTANT SELECTION ON SOYBEAN SOMACLONAL VARIANTS

    Directory of Open Access Journals (Sweden)

    Nur Basuki

    2012-02-01

    Full Text Available This research was conducted to evaluate the yield potential of 19 somaclonal variants resulting from in vitro selection when planted under drought stress condition in the field. Field test was done by planting the variants, the parents, and checked varieties in the field during dry season, and was irrigated once a week for non-stress and once two weeks for drought stress treatment. Split-plot design arranged in a factorial (2 x 28 with three replications was used in this research. Obser-vations were done on yield and yield components. Analysis of variance was used to see the difference between treatments and then it was continued with analysis using Honestly Significant Difference test to find out the best treatments. There was no interaction between genotype and drought stress on seed yield. Different genotypes showed a significant difference on this character. It indicated that the yield potential of selected variants was not affected by drought stress treatment. This research gave 10 variants having the potential to be developed as drought resistant genotypes. However, these ten potential geno-types need to be tested further in field trial to find out the yield adaptability and stability and their resistance to drought stress.

  13. Differences in crystallization of two LinB variants from Sphingobium japonicum UT26

    International Nuclear Information System (INIS)

    Degtjarik, Oksana; Chaloupkova, Radka; Rezacova, Pavlina; Kuty, Michal; Damborsky, Jiri; Kuta Smatanova, Ivana

    2013-01-01

    To study enzyme functionality, two haloalkane dehalogenase variants LinB32 and LinB70 carrying single-point and double-point mutations were constructed and crystallized in different crystallization conditions. Both LinB variants and their complexes with halogenated substrates diffracted to resolutions ranging from 1.6 to 2.8 Å. Haloalkane dehalogenases are microbial enzymes that convert a broad range of halogenated aliphatic compounds to their corresponding alcohols by the hydrolytic mechanism. These enzymes play an important role in the biodegradation of various environmental pollutants. Haloalkane dehalogenase LinB isolated from a soil bacterium Sphingobium japonicum UT26 has a relatively broad substrate specificity and can be applied in bioremediation and biosensing of environmental pollutants. The LinB variants presented here, LinB32 and LinB70, were constructed with the goal of studying the effect of mutations on enzyme functionality. In the case of LinB32 (L117W), the introduced mutation leads to blocking of the main tunnel connecting the deeply buried active site with the surrounding solvent. The other variant, LinB70 (L44I, H107Q), has the second halide-binding site in a position analogous to that in the related haloalkane dehalogenase DbeA from Bradyrhizobium elkanii USDA94. Both LinB variants were successfully crystallized and full data sets were collected for native enzymes as well as their complexes with the substrates 1,2-dibromoethane (LinB32) and 1-bromobutane (LinB70) to resolutions ranging from 1.6 to 2.8 Å. The two mutants crystallize differently from each other, which suggests that the mutations, although deep inside the molecule, can still affect the protein crystallizability

  14. Compaction of full size blocks of bentonite for the KBS-3 concept. Initial tests for evaluating the technique

    International Nuclear Information System (INIS)

    Johanesson, Lars-Erik

    1999-12-01

    Besides the test with the compaction device several other pieces of equipment were tested for the mixing of the bentonite with water, filling of the form with bentonite and lifting of the blocks. The tests of the equipment turned out well. Furthermore the density of the compacted bentonite was in parity with the expected. The compacted blocks had grooves and flanges in order to facilitate the emplacement of the blocks. Unacceptable damages and cracks close to the flanges were observed on the blocks with low water ratio. As a consequence of these damages it is recommended that the form is modified so that blocks with plane surfaces can be made

  15. Misgivings about the Matching Familiar Figures Test: A Brief Reply to Block, Gjerde, and Block (1986).

    Science.gov (United States)

    Kagan, Jerome

    1987-01-01

    Reply by Jerome Kagan to a recent article by Block, Gjerde, and Block (1986) which questions the validity of the construct of reflection-impulsivity. Kagan alleges flaws in the logic of the authors' (Block, Gjerde, Block) position and in the inferences drawn from their data. (Author/RWB)

  16. 31 CFR 544.204 - Expenses of maintaining blocked physical property; liquidation of blocked property.

    Science.gov (United States)

    2010-07-01

    ... physical property; liquidation of blocked property. 544.204 Section 544.204 Money and Finance: Treasury... maintaining blocked physical property; liquidation of blocked property. (a) Except as otherwise authorized..., all expenses incident to the maintenance of physical property blocked pursuant to § 544.201(a) shall...

  17. 31 CFR 547.204 - Expenses of maintaining blocked physical property; liquidation of blocked property.

    Science.gov (United States)

    2010-07-01

    ... physical property; liquidation of blocked property. 547.204 Section 547.204 Money and Finance: Treasury... maintaining blocked physical property; liquidation of blocked property. (a) Except as otherwise authorized..., all expenses incident to the maintenance of physical property blocked pursuant to § 547.201(a) shall...

  18. 31 CFR 593.204 - Expenses of maintaining blocked physical property; liquidation of blocked account.

    Science.gov (United States)

    2010-07-01

    ... physical property; liquidation of blocked account. 593.204 Section 593.204 Money and Finance: Treasury... maintaining blocked physical property; liquidation of blocked account. (a) Except as otherwise authorized, and... to the maintenance of physical property blocked pursuant to § 593.201(a) shall be the responsibility...

  19. 31 CFR 587.205 - Expenses of maintaining blocked property; liquidation of blocked account.

    Science.gov (United States)

    2010-07-01

    ... property; liquidation of blocked account. 587.205 Section 587.205 Money and Finance: Treasury Regulations....205 Expenses of maintaining blocked property; liquidation of blocked account. (a) Except as otherwise... standard time, January 19, 2001, all expenses incident to the maintenance of physical property blocked...

  20. Mathematical modeling and simulation of nanopore blocking by precipitation

    KAUST Repository

    Wolfram, M-T

    2010-10-29

    High surface charges of polymer pore walls and applied electric fields can lead to the formation and subsequent dissolution of precipitates in nanopores. These precipitates block the pore, leading to current fluctuations. We present an extended Poisson-Nernst-Planck system which includes chemical reactions of precipitation and dissolution. We discuss the mathematical modeling and present 2D numerical simulations. © 2010 IOP Publishing Ltd.

  1. Neuromuscular Activity of Upper and Lower Limbs during two Backstroke Swimming Start Variants

    Directory of Open Access Journals (Sweden)

    Karla De Jesus, Kelly De Jesus, Alexandre I. A. Medeiros, Pedro Gonçalves, Pedro Figueiredo, Ricardo J. Fernandes, João Paulo Vilas-Boas

    2015-09-01

    Full Text Available A proficient start is decisive in sprint competitive swimming events and requires swimmers’ to exert maximal forces in a short period to complete the task successfully. The aim of this study was to compare the electromyographic (EMG activity in-between the backstroke start with feet positioned parallel and partially emerged performed with the hands on the highest horizontal and on the vertical handgrip at hands-off, take-off, flight and entry start phases. EMG comparisons between starting variants were supported by upper and lower limb joint angles at starting position and 15 m start time data. Following a four-week start training to familiarize participants with each start variant, 10 male competitive backstroke swimmers performed randomly six 15 m maximal trials, being three of each start variant. Surface EMG of Biceps Brachii, Triceps Brachii, Rectus Femoris, Biceps Femoris, Gastrocnemius Medialis and Tibialis Anterior was recorded and processed using the time integral EMG (iEMG. Eight video cameras (four surface and four underwater were used to determine backstroke start phases and joint angles at starting position. EMG, joint angles and temporal parameters have not evidenced changes due to the different handgrips. Nevertheless, clear differences were observed in both variants for upper and lower limb muscles activity among starting phases (e.g. Biceps Brachii at take-off vs. flight phase, 15.17% ± 2.76% and 22.38% ± 4.25%; 14.24% ± 7.11% and 25.90% ± 8.65%, for variant with hands horizontal and vertically positioned, respectively. It was concluded that different handgrips did not affect EMG, kinematics and temporal profile in backstroke start. Despite coaches might plan similar strength training for both start variants, further attention should be given on the selection of proper exercises to maximize the contribution of relevant muscles at different starting phases.

  2. Anti-Biofouling Properties of Comblike Block Copolymers with Amphiphilic Side Chains

    International Nuclear Information System (INIS)

    Krishnan, S.; Ayothi, R.; Hexemer, A.; Finlay, J.; Sohn, K.; Perry, R.; Ober, C.; Kramer, E.; Callow, M.

    2006-01-01

    Surfaces of novel block copolymers with amphiphilic side chains were studied for their ability to influence the adhesion of marine organisms. The surface-active polymer, obtained by grafting fluorinated molecules with hydrophobic and hydrophilic blocks to a block copolymer precursor, showed interesting bioadhesion properties. Two different algal species, one of which adhered strongly to hydrophobic surfaces, and the other, to hydrophilic surfaces, showed notably weak adhesion to the amphiphilic surfaces. Both organisms are known to secrete adhesive macromolecules, with apparently different wetting characteristics, to attach to underwater surfaces. The ability of the amphiphilic surface to undergo an environment-dependent transformation in surface chemistry when in contact with the extracellular polymeric substances is a possible reason for its antifouling nature. Near-edge X-ray absorption fine structure spectroscopy (NEXAFS) was used, in a new approach based on angle-resolved X-ray photoelectron spectroscopy (XPS), to determine the variation in chemical composition within the top few nanometers of the surface and also to study the surface segregation of the amphiphilic block. A mathematical model to extract depth-profile information from the normalized NEXAFS partial electron yield is developed

  3. A sharp recovery condition for block sparse signals by block orthogonal multi-matching pursuit

    OpenAIRE

    Chen, Wengu; Ge, Huanmin

    2016-01-01

    We consider the block orthogonal multi-matching pursuit (BOMMP) algorithm for the recovery of block sparse signals. A sharp bound is obtained for the exact reconstruction of block $K$-sparse signals via the BOMMP algorithm in the noiseless case, based on the block restricted isometry constant (block-RIC). Moreover, we show that the sharp bound combining with an extra condition on the minimum $\\ell_2$ norm of nonzero blocks of block $K-$sparse signals is sufficient to recover the true support ...

  4. Splicing analysis of 14 BRCA1 missense variants classifies nine variants as pathogenic

    DEFF Research Database (Denmark)

    Ahlborn, Lise B; Dandanell, Mette; Steffensen, Ane Y

    2015-01-01

    Pathogenic germline mutations in the BRCA1 gene predispose carriers to early onset breast and ovarian cancer. Clinical genetic screening of BRCA1 often reveals variants with uncertain clinical significance, complicating patient and family management. Therefore, functional examinations are urgently...

  5. New poly(dimethylsiloxane)/poly(perfluorooctylethyl acrylate) block copolymers: structure and order across multiple length scales in thin films

    KAUST Repository

    Martinelli, Elisa

    2011-01-01

    Three sets of a new class of low surface tension block copolymers were synthesized consisting of a poly(dimethylsiloxane) (PDMS) block and a poly(perfluorooctylethyl acrylate) (AF8) block. The polymers were prepared using a bromo-terminated PDMS macroinitiator, to which was attached an AF8 block grown using atom transfer radical polymerization (ATRP) in such a designed way that the molecular weight and composition of the two polymer blocks were regularly varied. The interplay of both the phase separated microstructure and the mesomorphic character of the fluorinated domains with their effect on surface structure was evaluated using a suite of analytical tools. Surfaces of spin-coated and thermally annealed films were assessed using a combination of X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure (NEXAFS) studies. Both atomic force microscopy (AFM) measurements and grazing incidence small angle X-ray scattering (GISAXS) studies were carried out to evaluate the microstructure of the thin films. Even in block copolymers in which the PDMS block was the majority component, a significant presence of the lower surface energy AF8 block was detected at the film surface. Moreover, the perfluorooctyl helices of the AF8 repeat units were highly oriented at the surface in an ordered, tilted smectic structure, which was compared with those of the bulk powder samples using wide-angle X-ray powder diffraction (WAXD) studies. © 2011 The Royal Society of Chemistry.

  6. Morphological variants of renal carcinoma in radical nephrectomy specimens

    International Nuclear Information System (INIS)

    Humera, A.; Kehar, I.

    2015-01-01

    To determine the morphological variants of Renal Cell Carcinoma (RCC) to detect the commonest histopathological type with special focus to the newly introduced entity Clear Cell Papillary Renal Cell Carcinoma (CCPRCC). Study Design: Case series. Place and Duration of Study: Department of Pathology, Basic Medical Sciences Institute, JPMC, Karachi, from January 2007 to December 2012. Methodology: Paraffin embedded blocks of 32 cases of radical nephrectomy specimens for renal mass were selected from records of Pathology Department, BMSI. Cases were excluded due to inadequate biopsies. Remaining 30 cases of renal cell carcinoma were included in study. H and E staining was done for all cases and PAS stain was employed for a few cases. All cases were reviewed under light microscope. Results: The 30 cases of renal cell carcinoma included 21 (70%) clear cell renal cell carcinoma, 03 (10%) clear cell papillary renal cell carcinoma, 02 (6.6%) papillary renal cell carcinoma and 04 (13.33%) hybrid tumors. Majority of cases (53.3%) found in age range between 40 - 60 years while 23.33% cases were found in 7th and 6.6% in 8th decade of life. While 16.66% cases were in younger age group that is between 31 - 40 years of age. Sixty percent cases of right radical nephrectomies and 40% cases of left radical nephrectomies. Conclusion: CCRCC was most common histopathologic type followed by CCPRCC, hybrid tumors and PRCC. (author)

  7. Blocking for Sequential Political Experiments.

    Science.gov (United States)

    Moore, Ryan T; Moore, Sally A

    2013-10-01

    In typical political experiments, researchers randomize a set of households, precincts, or individuals to treatments all at once, and characteristics of all units are known at the time of randomization. However, in many other experiments, subjects "trickle in" to be randomized to treatment conditions, usually via complete randomization. To take advantage of the rich background data that researchers often have (but underutilize) in these experiments, we develop methods that use continuous covariates to assign treatments sequentially. We build on biased coin and minimization procedures for discrete covariates and demonstrate that our methods outperform complete randomization, producing better covariate balance in simulated data. We then describe how we selected and deployed a sequential blocking method in a clinical trial and demonstrate the advantages of our having done so. Further, we show how that method would have performed in two larger sequential political trials. Finally, we compare causal effect estimates from differences in means, augmented inverse propensity weighted estimators, and randomization test inversion.

  8. Exercising with blocked muscle glycogenolysis

    DEFF Research Database (Denmark)

    Nielsen, Tue L; Pinós, Tomàs; Brull, Astrid

    2018-01-01

    of expression and activation of proteins involved in glycolytic flux revealed that in glycolytic, but not oxidative muscle from exercised McArdle mice, the glycolytic flux had changed compared to that in wild-type mice. Specifically, exercise triggered in glycolytic muscle a differentiated activation of insulin......BACKGROUND: McArdle disease (glycogen storage disease type V) is an inborn error of skeletal muscle metabolism, which affects glycogen phosphorylase (myophosphorylase) activity leading to an inability to break down glycogen. Patients with McArdle disease are exercise intolerant, as muscle glycogen......-derived glucose is unavailable during exercise. Metabolic adaptation to blocked muscle glycogenolysis occurs at rest in the McArdle mouse model, but only in highly glycolytic muscle. However, it is unknown what compensatory metabolic adaptations occur during exercise in McArdle disease. METHODS: In this study, 8...

  9. A Modified P1 Moiety Enhances In Vitro Antiviral Activity against Various Multidrug-Resistant HIV-1 Variants and In Vitro Central Nervous System Penetration Properties of a Novel Nonpeptidic Protease Inhibitor, GRL-10413.

    Science.gov (United States)

    Amano, Masayuki; Salcedo-Gómez, Pedro Miguel; Zhao, Rui; Yedidi, Ravikiran S; Das, Debananda; Bulut, Haydar; Delino, Nicole S; Sheri, Venkata Reddy; Ghosh, Arun K; Mitsuya, Hiroaki

    2016-12-01

    We report here that GRL-10413, a novel nonpeptidic HIV-1 protease inhibitor (PI) containing a modified P1 moiety and a hydroxyethylamine sulfonamide isostere, is highly active against laboratory HIV-1 strains and primary clinical isolates (50% effective concentration [EC 50 ] of 0.00035 to 0.0018 μM), with minimal cytotoxicity (50% cytotoxic concentration [CC 50 ] = 35.7 μM). GRL-10413 blocked the infectivity and replication of HIV-1 NL4-3 variants selected by use of atazanavir, lopinavir, or amprenavir (APV) at concentrations of up to 5 μM (EC 50 = 0.0021 to 0.0023 μM). GRL-10413 also maintained its strong antiviral activity against multidrug-resistant clinical HIV-1 variants isolated from patients who no longer responded to various antiviral regimens after long-term antiretroviral therapy. The development of resistance against GRL-10413 was significantly delayed compared to that against APV. In addition, GRL-10413 showed favorable central nervous system (CNS) penetration properties as assessed with an in vitro blood-brain barrier (BBB) reconstruction system. Analysis of the crystal structure of HIV-1 protease in complex with GRL-10413 demonstrated that the modified P1 moiety of GRL-10413 has a greater hydrophobic surface area and makes greater van der Waals contacts with active site amino acids of protease than in the case of darunavir. Moreover, the chlorine substituent in the P1 moiety interacts with protease in two distinct configurations. The present data demonstrate that GRL-10413 has desirable features for treating patients infected with wild-type and/or multidrug-resistant HIV-1 variants, with favorable CNS penetration capability, and that the newly modified P1 moiety may confer desirable features in designing novel anti-HIV-1 PIs. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  10. Influenza A (H3N2) Variant Virus

    Science.gov (United States)

    ... Swine Variant Pandemic Other Influenza A (H3N2) Variant Virus Language: English (US) Español Recommend on Facebook Tweet Share Compartir Influenza viruses that normally circulate in pigs are called “variant” ...

  11. Analyzing block placement errors in SADP patterning

    Science.gov (United States)

    Kobayashi, Shinji; Okada, Soichiro; Shimura, Satoru; Nafus, Kathleen; Fonseca, Carlos; Demand, Marc; Biesemans, Serge; Versluijs, Janko; Ercken, Monique; Foubert, Philippe; Miyazaki, Shinobu

    2016-03-01

    We discuss edge placement errors (EPE) for multi-patterning of Mx critical layers using ArF lithography. Specific focus is placed on the block formation part of the process. While plenty of literature characterization data exist on spacer formation, only limited published data is available on block processes. We analyze the accuracy of placing blocks relative to narrow spacers. Many publications calculate EPE assuming Gaussian distributions for key process variations contributing to EPE. For practical reasons, each contributor is measured on dedicated test structures. In this work, we complement such analysis and directly measure the EPE in product. We perform high density sampling of blocks using CDSEM images and analyze all feature edges of interest. We find that block placement errors can be very different depending on their local design context. Specifically we report on 2 block populations (further called block A and B) which have a 4x different standard deviation. We attribute this to differences in local topography (spacer shape) and interaction with the plasma-etch process design. Block A (on top of the `core space' S1) has excellent EPE uniformity of ~1 nm while block B (on top of `gap space' S2) has degraded EPE control of ~4 nm. Finally, we suggest that the SOC etch process is at the origin on positioning blocks accurately on slim spacers, helping the manufacturability of spacer-based patterning techniques, and helping its extension toward the 5nm node.

  12. Combined analyses of 20 common obesity susceptibility variants

    DEFF Research Database (Denmark)

    Sandholt, Camilla Helene; Sparsø, Thomas; Grarup, Niels

    2010-01-01

    Genome-wide association studies and linkage studies have identified 20 validated genetic variants associated with obesity and/or related phenotypes. The variants are common, and they individually exhibit small-to-modest effect sizes.......Genome-wide association studies and linkage studies have identified 20 validated genetic variants associated with obesity and/or related phenotypes. The variants are common, and they individually exhibit small-to-modest effect sizes....

  13. Studies on microphase-separated structures of block copolymers by neutron reflectivity measurement

    International Nuclear Information System (INIS)

    Torikai, Naoya; Noda, Ichiro; Matsushita, Yushu; Karim, A.; Satija, S.K.; Han, C.C.; Ebisawa, Toru.

    1996-01-01

    Segmental distributions of block copolymer chains in lamellar microphase-separated structure and those of homopolymers in block copolymer/homopolymer blends also with lamellar structures were studied by neutron reflectivity measurements. It was revealed that polystyrene and poly(2-vinylpyridine) lamellae were alternately stacked within the thin films of pure block copolymers spin-coated on silicon wafers, and they were preferentially oriented along the direction parallel to film surface. Polystyrene lamella appeared at air surfaces of the films, while poly(2-vinylpyridine) lamella did on silicon surfaces. Segment distribution at lamellar interface was well described by an error function, and the width of the lamellar interface, defined by a full-width half-maximum value of interfacial profile, was estimated to be about 4.5 nm. Segments of block chains adjacent to the chemical junction points connecting different block chains were strongly localized near the lamellar interfaces, while those on the free ends of block chains were distributed all over the lamellar microdomains with their distribution maxima at the centers of lamellae. On the other hand, it was clarified that homopolymers dissolved in the corresponding lamellar microdomains of block copolymers were also distributed throughout the microdomains with their concentration maxima at the centers of the lamellae. (author)

  14. GenOVa: a computer program to generate orientational variants

    OpenAIRE

    Cayron, Cyril

    2007-01-01

    A computer program called GenOVa, written in Python, calculates the orientational variants, the operators (special types of misorientations between variants) and the composition table associated with a groupoid structure. The variants can be represented by three-dimensional shapes or by pole figures.

  15. variant formula for predicting peak expiratory flow rate in pregnant ...

    African Journals Online (AJOL)

    DR. AMINU

    The graph illustrates close association of variant formula with the observed values of PEFR obtained from the study. Variant formula may be useful in clinical setting to assess people with respiratory disorders especially asthma. Key words: Variant formula, Peak expiratory flow rate, Pregnancy, Kura local government area.

  16. Peculiarities of Clutch Forming Rails and Wheel Block Construction

    Science.gov (United States)

    Shiler, V. V.; Galiev, I. I.; Shiler, A. V.

    2018-03-01

    The clutch of the wheel and rail is significantly influenced by the design features of the standard wheel pair, which are manifested in the presence of "parasitic" slipping of the wheels along the rails during its movement. The purpose of the presented work is to evaluate new design solutions for wheel sets. The research was carried out using methods of comparative simulation modelling and physical prototyping. A new design of the wheel pair (block wheel pair) is proposed, which features an independent rotation of all surfaces of the wheels in contact with the rails. The block construction of the wheel pair forms open mechanical contours with the track gauge, which completely eliminates the "parasitic" slippage. As a result, in the process of implementing traction or braking forces, the coupling coefficient of the block construction of the wheel pair is significantly higher than that of existing structures. In addition, in the run-out mode, the resistance to movement of the block wheel pair is half as much. All this will allow one to significantly reduce the energy consumption for traction of trains, wear of track elements and crew, and to increase the speed and safety of train traffic.

  17. Spinning top urethra: not a normal variant.

    Science.gov (United States)

    Saxton, H M; Borzyskowski, M; Mundy, A R; Vivian, G C

    1988-07-01

    Spinning top urethra (STU) is a term used to describe a widened posterior urethra seen mainly in girls. It is commonly regarded as a normal variant. The authors studied 30 girls with STU using videourodynamics. Twenty-eight showed bladder instability; 21, a congenital wide bladder neck anomaly; and 20, both instability and a wide bladder neck. One patient had a sensitive bladder. All patients had a urodynamic abnormality. The authors believe that the STU is nearly always an indication of bladder instability or wide bladder neck anomaly. The most common mechanism for the dilatation of the posterior urethra is that unstable contractions are resisted by a voluntary increase in distal sphincter tension so as to prevent leakage of urine. The resulting pressure rise produces distention of the posterior urethra, which will be maximal in subjects with a weak bladder neck mechanism as in the congenital wide bladder neck anomaly. The authors believe that STU is seldom if ever a normal variant.

  18. On Variant Reflected Backward SDEs, with Applications

    Directory of Open Access Journals (Sweden)

    Jin Ma

    2009-01-01

    Bank and El Karoui (2004, and is hence named the “Variant Reflected BSDEs” (VRBSDE in this paper. The special nature of the Variant Skorohod problem leads to a hidden forward-backward feature of the BSDE, and as a consequence this type of BSDE cannot be treated in a usual way. We shall prove that in a small-time duration most of the well-posedness, comparison, and stability results are still valid, although some extra conditions on the boundary process are needed. We will also provide some possible applications where the VRBSDE can be potentially useful. These applications show that the VRBSDE could become a novel tool for some problems in finance and optimal stopping problems where no existing methods can be easily applicable.

  19. Angiography of histopathologic variants of synovial sarcoma

    International Nuclear Information System (INIS)

    Lois, J.F.; Fischer, H.J.; Mirra, J.M.; Gomes, A.S.; California Univ., Los Angeles

    1986-01-01

    Synovial sarcomas are rare soft tissue tumors which histopathologically can be divided into monophasic, biphasic and mixed variants. As part of a protocol for intra-arterial chemotherapy 12 patients with biopsy proven synovial sarcoma underwent angiography. The angiograms on these patients were reviewed to determine whether synovial sarcomas and their variants demonstrated a characteristic angiographic appearance. Synovial sarcomas appeared angiographically as soft tissue masses which showed a fine network of tumor vessels with an inhomogeneous capillary blush. Their degree of vascularity varied according to their histopathology. Monophasic synovial sarcomas demonstrated in general a higher degree of neovascularity than the biphasic form. This finding was also suggested by histopathologic analysis of the vessels in the tumor. Although angiography did not show a distinctive vascular pattern it may be useful to evaluate tumor size and vascularity. (orig.)

  20. Formation of nanophases in epoxy thermosets containing amphiphilic block copolymers with linear and star-like topologies.

    Science.gov (United States)

    Wang, Lei; Zhang, Chongyin; Cong, Houluo; Li, Lei; Zheng, Sixun; Li, Xiuhong; Wang, Jie

    2013-07-11

    In this work, we investigated the effect of topological structures of block copolymers on the formation of the nanophase in epoxy thermosets containing amphiphilic block copolymers. Two block copolymers composed of poly(ε-caprolactone) (PCL) and poly(2,2,2-trifluoroethyl acrylate) (PTFEA) blocks were synthesized to possess linear and star-shaped topologies. The star-shaped block copolymer composed a polyhedral oligomeric silsesquioxane (POSS) core and eight poly(ε-caprolactone)-block-poly(2,2,2-trifluoroethyl acrylate) (PCL-b-PTFEA) diblock copolymer arms. Both block copolymers were synthesized via the combination of ring-opening polymerization and reversible addition-fragmentation chain transfer/macromolecular design via the interchange of xanthate (RAFT/MADIX) process; they were controlled to have identical compositions of copolymerization and lengths of blocks. Upon incorporating both block copolymers into epoxy thermosets, the spherical PTFEA nanophases were formed in all the cases. However, the sizes of PTFEA nanophases from the star-like block copolymer were significantly lower than those from the linear diblock copolymer. The difference in the nanostructures gave rise to the different glass transition behavior of the nanostructured thermosets. The dependence of PTFEA nanophases on the topologies of block copolymers is interpreted in terms of the conformation of the miscible subchain (viz. PCL) at the surface of PTFEA microdomains and the restriction of POSS cages on the demixing of the thermoset-philic block (viz. PCL).

  1. A block for nuclear reactor reflector covers

    International Nuclear Information System (INIS)

    Helm, H.

    1980-01-01

    The graphite block with hexagonal profile is provided with cylindrical channels passing from the corners of the upper end face towards the diagonally opposed corners of the lower end face. These channels enable gas cooling of the blocks joined together and avoid direct escape of neutrons. The blocks can also be joined together in such way that they form even-cylindrical channel for control rods for example. (GL) [de

  2. Fine-Mapping of Common Genetic Variants Associated with Colorectal Tumor Risk Identified Potential Functional Variants.

    Directory of Open Access Journals (Sweden)

    Mengmeng Du

    Full Text Available Genome-wide association studies (GWAS have identified many common single nucleotide polymorphisms (SNPs associated with colorectal cancer risk. These SNPs may tag correlated variants with biological importance. Fine-mapping around GWAS loci can facilitate detection of functional candidates and additional independent risk variants. We analyzed 11,900 cases and 14,311 controls in the Genetics and Epidemiology of Colorectal Cancer Consortium and the Colon Cancer Family Registry. To fine-map genomic regions containing all known common risk variants, we imputed high-density genetic data from the 1000 Genomes Project. We tested single-variant associations with colorectal tumor risk for all variants spanning genomic regions 250-kb upstream or downstream of 31 GWAS-identified SNPs (index SNPs. We queried the University of California, Santa Cruz Genome Browser to examine evidence for biological function. Index SNPs did not show the strongest association signals with colorectal tumor risk in their respective genomic regions. Bioinformatics analysis of SNPs showing smaller P-values in each region revealed 21 functional candidates in 12 loci (5q31.1, 8q24, 11q13.4, 11q23, 12p13.32, 12q24.21, 14q22.2, 15q13, 18q21, 19q13.1, 20p12.3, and 20q13.33. We did not observe evidence of additional independent association signals in GWAS-identified regions. Our results support the utility of integrating data from comprehensive fine-mapping with expanding publicly available genomic databases to help clarify GWAS associations and identify functional candidates that warrant more onerous laboratory follow-up. Such efforts may aid the eventual discovery of disease-causing variant(s.

  3. Building blocks for protein interaction devices.

    Science.gov (United States)

    Grünberg, Raik; Ferrar, Tony S; van der Sloot, Almer M; Constante, Marco; Serrano, Luis

    2010-05-01

    Here, we propose a framework for the design of synthetic protein networks from modular protein-protein or protein-peptide interactions and provide a starter toolkit of protein building blocks. Our proof of concept experiments outline a general work flow for part-based protein systems engineering. We streamlined the iterative BioBrick cloning protocol and assembled 25 synthetic multidomain proteins each from seven standardized DNA fragments. A systematic screen revealed two main factors controlling protein expression in Escherichia coli: obstruction of translation initiation by mRNA secondary structure or toxicity of individual domains. Eventually, 13 proteins were purified for further characterization. Starting from well-established biotechnological tools, two general-purpose interaction input and two readout devices were built and characterized in vitro. Constitutive interaction input was achieved with a pair of synthetic leucine zippers. The second interaction was drug-controlled utilizing the rapamycin-induced binding of FRB(T2098L) to FKBP12. The interaction kinetics of both devices were analyzed by surface plasmon resonance. Readout was based on Förster resonance energy transfer between fluorescent proteins and was quantified for various combinations of input and output devices. Our results demonstrate the feasibility of parts-based protein synthetic biology. Additionally, we identify future challenges and limitations of modular design along with approaches to address them.

  4. La influencia de la superficie articular y la membrana sinovial en la evolución de pacientes afectos por bloqueo crónico de la articulación temporomandibular tratados mediante artroscopia Influence of the joint surface and the synovial membrane on the evolution of patients affected by chronic temporomandibular joint block who were treated with arthroscopic surgery

    Directory of Open Access Journals (Sweden)

    R. González-García

    2010-03-01

    Full Text Available Introducción: Se ha referido la artroscopia de la articulación temporomandibular (ATM como una técnica efectiva en el tratamiento del bloqueo crónico (BC articular. El propósito del presente estudio es evaluar si el estado de la superficie articular y la membrana sinovial directamente visualizados por artroscopia pueden determinar el resultado posoperatorio de pacientes afectos por BC de la ATM. Pacientes y método: Doscientos cincuenta y siete de 500 pacientes (344 articulaciones cumplieron los criterios de inclusión para BC de la ATM. Para el presente estudio se seleccionaron 172 pacientes con afectación unilateral. Se eligieron los parámetros "sinovitis" y "condromalacia" para la evaluación de la membrana sinovial y la superficie articular, respectivamente. Se establecieron dos grupos de pacientes: a pacientes con afectación leve: sinovitis grados I/II más condromalacia I/II, y b pacientes con afectación grave: sinovitis grados III/IV más condromalacia grados III/IV. Se eligieron el dolor y la máxima apertura oral (MAO interincisal como variables dependientes. Todos los pacientes se revisaron de modo posoperatorio al mes, 3, 6, 12 y 24 meses. Se utilizó la prueba de la "t" de Student para muestras pareadas para comparar los valores medios de dolor (escala visual analógica, EVA y función (MAO, de modo preoperatorio y posoperatorio. Se utilizó la "t" de Student para muestras independientes para la comparación de los diferentes grupos establecidos. Se consideró estadísticamente significativo un valor de p Introduction: Arthroscopy of the temporomandibular joint (TMJ has been considered an effective technique to treat close lock (CL. The purpose of this study is to evaluate if the status of the joint surface and the synovial membrane directly seen via arthroscopy can determine the post operative results of patients with chronic block of the TMJ. Patients and methods: Two hundred and fifty-seven out of the 500 patients (344

  5. Amphiphilic block copolymer/poly(dimethylsiloxane) (PDMS) blends and nanocomposites for improved fouling-release.

    Science.gov (United States)

    Martinelli, Elisa; Suffredini, Marianna; Galli, Giancarlo; Glisenti, Antonella; Pettitt, Michala E; Callow, Maureen E; Callow, James A; Williams, David; Lyall, Graeme

    2011-05-01

    Amphiphilic diblock copolymers, Sz6 and Sz12, consisting of a poly(dimethylsiloxane) block (average degree of polymerisation = 132) and a PEGylated-fluoroalkyl modified polystyrene block (Sz, average degree of polymerisation = 6, 12) were prepared by atom transfer radical polymerization (ATRP). Coatings were obtained from blends of either block copolymer (1-10 wt%) with a poly(dimethylsiloxane) (PDMS) matrix. The coating surface presented a simultaneous hydrophobic and lipophobic character, owing to the strong surface segregation of the lowest surface energy fluoroalkyl chains of the block copolymer. Surface chemical composition and wettability of the films were affected by exposure to water. Block copolymer Sz6 was also blended with PDMS and a 0.1 wt% amount of multiwall carbon nanotubes (CNT). The excellent fouling-release (FR) properties of these new coatings against the macroalga Ulva linza essentially resulted from the inclusion of the amphiphilic block copolymer, while the addition of CNT did not appear to improve the FR properties.

  6. Differences in crystallization of two LinB variants from Sphingobium japonicum UT26.

    Science.gov (United States)

    Degtjarik, Oksana; Chaloupkova, Radka; Rezacova, Pavlina; Kuty, Michal; Damborsky, Jiri; Kuta Smatanova, Ivana

    2013-03-01

    Haloalkane dehalogenases are microbial enzymes that convert a broad range of halogenated aliphatic compounds to their corresponding alcohols by the hydrolytic mechanism. These enzymes play an important role in the biodegradation of various environmental pollutants. Haloalkane dehalogenase LinB isolated from a soil bacterium Sphingobium japonicum UT26 has a relatively broad substrate specificity and can be applied in bioremediation and biosensing of environmental pollutants. The LinB variants presented here, LinB32 and LinB70, were constructed with the goal of studying the effect of mutations on enzyme functionality. In the case of LinB32 (L117W), the introduced mutation leads to blocking of the main tunnel connecting the deeply buried active site with the surrounding solvent. The other variant, LinB70 (L44I, H107Q), has the second halide-binding site in a position analogous to that in the related haloalkane dehalogenase DbeA from Bradyrhizobium elkanii USDA94. Both LinB variants were successfully crystallized and full data sets were collected for native enzymes as well as their complexes with the substrates 1,2-dibromoethane (LinB32) and 1-bromobutane (LinB70) to resolutions ranging from 1.6 to 2.8 Å. The two mutants crystallize differently from each other, which suggests that the mutations, although deep inside the molecule, can still affect the protein crystallizability.

  7. Differences in crystallization of two LinB variants from Sphingobium japonicum UT26

    Science.gov (United States)

    Degtjarik, Oksana; Chaloupkova, Radka; Rezacova, Pavlina; Kuty, Michal; Damborsky, Jiri; Kuta Smatanova, Ivana

    2013-01-01

    Haloalkane dehalogenases are microbial enzymes that convert a broad range of halogenated aliphatic compounds to their corresponding alcohols by the hydrolytic mechanism. These enzymes play an important role in the biodegradation of various environmental pollutants. Haloalkane dehalogenase LinB isolated from a soil bacterium Sphingobium japonicum UT26 has a relatively broad substrate specificity and can be applied in bioremediation and biosensing of environmental pollutants. The LinB variants presented here, LinB32 and LinB70, were constructed with the goal of studying the effect of mutations on enzyme functionality. In the case of LinB32 (L117W), the introduced mutation leads to blocking of the main tunnel connecting the deeply buried active site with the surrounding solvent. The other variant, LinB70 (L44I, H107Q), has the second halide-binding site in a position analogous to that in the related haloalkane dehalogenase DbeA from Bradyrhizobium elkanii USDA94. Both LinB variants were successfully crystallized and full data sets were collected for native enzymes as well as their complexes with the substrates 1,2-dibromoethane (LinB32) and 1-bromobutane (LinB70) to resolutions ranging from 1.6 to 2.8 Å. The two mutants crystallize differently from each other, which suggests that the mutations, although deep inside the molecule, can still affect the protein crystallizability. PMID:23519805

  8. Clinical Relevance of Androgen Receptor Splice Variants in Castration-Resistant Prostate Cancer.

    Science.gov (United States)

    Maughan, Benjamin L; Antonarakis, Emmanuel S

    2015-12-01

    Metastatic castration-resistant prostate cancer (mCRPC) currently benefits from a wealth of treatment options, yet still remains lethal in the vast majority of patients. It is becoming increasingly understood that this disease entity continues to evolve over time, acquiring additional and diverse resistance mechanisms with each subsequent therapy used. This dynamic relationship between treatment pressure and disease resistance can be challenging for the managing clinician. The recent discovery of alternate splice variants of the androgen receptor (AR) is one potential mechanism of escape in mCRPC, and recognizing this resistance mechanism might be important for optimal treatment selection for our patients. AR-V7 appears to be the most relevant AR splice variant, and early clinical data suggest that it is a negative prognostic marker in mCRPC. Emerging evidence also suggests that detection of AR-V7 may be associated with resistance to novel hormonal therapy (abiraterone and enzalutamide) but may be compatible with sensitivity to taxane chemotherapy (docetaxel and cabazitaxel). Adding to this complexity is the observation that AR-V7 is a dynamic marker whose status may change across time and depending on selective pressures induced by different therapies. Finally, it is possible that AR-V7 may represent a therapeutic target in mCRPC if drugs can be designed that degrade or inhibit AR splice variants or block their transcriptional activity. Several such agents (including galeterone, EPI-506, and bromodomain/BET inhibitors) are now in clinical development.

  9. Warty Carcinoma Penis: An Uncommon Variant

    Directory of Open Access Journals (Sweden)

    Sushma Thapa

    2017-01-01

    Full Text Available Penile carcinoma frequency varies widely in different parts of the world and comprises 1–10% of all the malignancies in males. Majority of the cases of penile carcinoma are squamous cell carcinoma of penis comprising 60% to 70% of all cases. Warty carcinoma of penis is an unusual neoplasm and a variant of penile squamous cell carcinoma comprising 5%–10% of all the variants. The other histological variants include basaloid, verrucous, papillary, sarcomatous, mixed, and adenosquamous carcinoma. The various histological entities with an exophytic papillary lesions including warty carcinoma are together referred to as the “verruciform” group of neoplasms. The warty carcinoma has to be differentiated from these lesions and is typically distinguished by histological features of hyperkeratosis, arborescent papillomatosis, acanthosis, and prominent koilocytosis with nuclear pleomorphism. We present a case of 65-year-old male with growth measuring 6×4 cm in the penis who underwent total penectomy and was diagnosed as warty carcinoma penis.

  10. Spatially variant periodic structures in electromagnetics

    Science.gov (United States)

    Rumpf, Raymond C.; Pazos, Javier J.; Digaum, Jennefir L.; Kuebler, Stephen M.

    2015-01-01

    Spatial transforms are a popular technique for designing periodic structures that are macroscopically inhomogeneous. The structures are often required to be anisotropic, provide a magnetic response, and to have extreme values for the constitutive parameters in Maxwell's equations. Metamaterials and photonic crystals are capable of providing these, although sometimes only approximately. The problem still remains about how to generate the geometry of the final lattice when it is functionally graded, or spatially varied. This paper describes a simple numerical technique to spatially vary any periodic structure while minimizing deformations to the unit cells that would weaken or destroy the electromagnetic properties. New developments in this algorithm are disclosed that increase efficiency, improve the quality of the lattices and provide the ability to design aplanatic metasurfaces. The ability to spatially vary a lattice in this manner enables new design paradigms that are not possible using spatial transforms, three of which are discussed here. First, spatially variant self-collimating photonic crystals are shown to flow unguided waves around very tight bends using ordinary materials with low refractive index. Second, multi-mode waveguides in spatially variant band gap materials are shown to guide waves around bends without mixing power between the modes. Third, spatially variant anisotropic materials are shown to sculpt the near-field around electric components. This can be used to improve electromagnetic compatibility between components in close proximity. PMID:26217058

  11. [Dandy-Walker variant: Case report].

    Science.gov (United States)

    Cueva-Núñez, José E; Lozano-Bustillo, Alejandra; Irias-Álvarez, Merlyn S; Vásquez-Montes, Raúl F; Varela-González, Douglas M

    Dandy Walker variant is defined by a variable hypoplasia of the cerebellar vermix with or without posterior fossa increase and without tentorium elevation. describe the case of a rare disease and emphasise the need to clarify the aetiology of prenatal malformations, as well as its multidisciplinary management. A male patient, 8 years of age, with a history of Infantile Cerebral Palsy and epilepsy, who was admitted with a history of tonic-clonic seizures. He was admitted due to psycho-motor developmental delay. During his hospitalisation, he had multiple seizure episodes, controlled with anticonvulsants. A computerized tomography was performed, in which communication was observed between the cisterna magna and fourth ventricle (the latter increased in size). In addition, the cerebellar vermix showed a partial hypoplasia. All these findings were compatible with a variant of the Dandy Walker syndrome. Dandy Walker variant may be asymptomatic and the images found may not indicate them as the cause of developmental disorders, due to its association with multiple syndromes and chromosomal abnormalities. Clinical presentation and prognosis depends on the related disorders, and a multidisciplinary approach is important, because the treatment depends on the symptoms presented. Copyright © 2016 Sociedad Chilena de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

  12. The Learning Potentials of Number Blocks

    DEFF Research Database (Denmark)

    Majgaard, Gunver; Nielsen, Jacob; Misfeldt, Morten

    2012-01-01

    . The tool is called Number Blocks and it combines physical interaction, learning, and immediate feedback. Number Blocks supports the children's understanding of place value in the sense that it allows them to experiment with creating large numbers. We found the blocks contributed to the learning process...... in several ways. The blocks combined mathematics and play, and they included and supported children at different academic levels. The auditory representation, especially the enhanced rhythmic effects due to using speech synthesis, and the rhythm helped the children to pronounce large numbers. This creates...

  13. Modelling of multi-block data

    DEFF Research Database (Denmark)

    Høskuldsson, Agnar; Svinning, K.

    2006-01-01

    Here is presented a unified approach to modelling multi-block regression data. The starting point is a partition of the data X into L data blocks, X = (X-1, X-2,...X-L), and the data Y into M data-blocks, Y = (Y-1, Y-2,...,Y-M). The methods of linear regression, X -> Y, are extended to the case...... these methods can be extended to a network of data blocks. Examples of the optimisation procedures in a network are shown. The examples chosen are the ones that are useful to work within industrial production environments. The methods are illustrated by simulated data and data from cement production....

  14. Using Interference to Block RFID Tags

    DEFF Research Database (Denmark)

    Krigslund, Rasmus; Popovski, Petar; Pedersen, Gert Frølund

    We propose a novel method to block RFID tags from responding, using intentional interference. We focus on the experimental evaluation, where we impose interference on the download and uplink, respectively. The results are positive, where modulated CCI shows most effective to block a tag.......We propose a novel method to block RFID tags from responding, using intentional interference. We focus on the experimental evaluation, where we impose interference on the download and uplink, respectively. The results are positive, where modulated CCI shows most effective to block a tag....

  15. Recent developments in paediatric neuraxial blocks

    Directory of Open Access Journals (Sweden)

    Vrushali Chandrashekhar Ponde

    2012-01-01

    Full Text Available Paediatric anaesthesia and paediatric regional anaesthesia are intertwined. Almost all surgeries unless contradicted could be and should be supplemented with a regional block. The main objective of this review is to elaborate on the recent advances of the central neuraxial blocks, such as application of ultrasound guidance and electrical stimulation in the pursuit of safety and an objective end point. This review also takes account of the traditional technique and understand the benefits as well the risk of each as compared with the recent technique. The recent trends in choosing the most appropriate peripheral block for a given surgery thereby sparing the central neuroaxis is considered. A penile block for circumcision or a sciatic block for unilateral foot surgery, rather than caudal epidural would have a better risk benefit equation. Readers will find a special mention on the recent thoughts on continuous epidural analgesia in paediatrics, especially its rise and fall, yet its unique importance. Lastly, the issue of block placements under sedation or general anaesthesia with its implication in this special population is dealt with. We conducted searches in MEDLINE (PubMed and assessed the relevance of the abstracts of citations identified from literature searches. The search was carried out in English, for last 10 years, with the following key words: Recent advances in paediatric regional anaesthesia; ultrasound guidance for central neuraxial blocks in children; role of electrical stimulation in neuraxial blocks in children; complications in neuraxial block. Full-text articles of potentially relevant abstracts were retrieved for further review.

  16. A MAC Mode for Lightweight Block Ciphers

    DEFF Research Database (Denmark)

    Luykx, Atul; Preneel, Bart; Tischhauser, Elmar Wolfgang

    2016-01-01

    Lightweight cryptography strives to protect communication in constrained environments without sacrificing security. However, security often conflicts with efficiency, shown by the fact that many new lightweight block cipher designs have block sizes as low as 64 or 32 bits. Such low block sizes lead...... no effect on the security bound, allowing an order of magnitude more data to be processed per key. Furthermore, LightMAC is incredibly simple, has almost no overhead over the block cipher, and is parallelizable. As a result, LightMAC not only offers compact authentication for resource-constrained platforms...

  17. Role of textile substrate hydrophobicity on the adsorption of hydrosoluble nonionic block copolymers.

    Science.gov (United States)

    Song, Junlong; Salas, Carlos; Rojas, Orlando J

    2015-09-15

    The adsorption of polyalkylene glycols and co-polymers of ethylene oxide and propylene oxide on substrates relevant to textiles with varying surface energies (cellulose, polypropylene, nylon and polyester) was studied by using quartz crystal microgravimetry. Langmuirian-type isotherms were observed for the adsorption profiles of nonionic block polymers of different architectures. The affinity with the surfaces is discussed based on experimental observations, which highlights the role of hydrophobic effects. For a given type of block polymer, micellar and monomeric adsorption is governed by the balance of polymer structure (mainly, chain length of hydrophobic segments) and substrate's surface energy. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Building blocks of the universe

    International Nuclear Information System (INIS)

    Malamud, E.; O'Connor, C.; Cooper, A.

    1990-01-01

    COSI [Ohio's Center for Science and Industry], a well established science center, and SciTech, an emerging one, have formed a collaboration to develop a group of original interactive exhibits conveying to a wide audience the nature of the most fundamental features of the Universe, as revealed in the fascinating world of nuclear and particle science. These new exhibits will add to, and be supported by, the basic science exhibits which have already attracted large numbers of visitors to both centers. The new project, called Building Blocks of the Universe, aims to foster an appreciation of the way all features of the Universe arise from simple, basic rules and to lead the visitor from the perceived complexities of our surroundings, to the unperceived, but simpler features of the sub-nuclear world. It has already become apparent from individual prototypes that these simple but immensely far-reaching ideas can indeed be conveyed by hands-on exhibits. These exhibits will be linked and enhanced by an effective museum environment, using pictorial diagrams, accurate non-technical text, and artistic displays to create an atmosphere in which visitors can learn about phenomena beyond the range of direct perception. This paper describes the goals, content and organization of the exhibition. The authors also outline their experience with prototype exhibits, and thereby invite additional input into the development process

  19. Capturing Reality at Centre Block

    Science.gov (United States)

    Boulanger, C.; Ouimet, C.; Yeomans, N.

    2017-08-01

    The Centre Block of Canada's Parliament buildings, National Historic Site of Canada is set to undergo a major rehabilitation project that will take approximately 10 years to complete. In preparation for this work, Heritage Conservation Services (HCS) of Public Services and Procurement Canada has been completing heritage documentation of the entire site which includes laser scanning of all interior rooms and accessible confined spaces such as attics and other similar areas. Other documentation completed includes detailed photogrammetric documentation of rooms and areas of high heritage value. Some of these high heritage value spaces present certain challenges such as accessibility due to the height and the size of the spaces. Another challenge is the poor lighting conditions, requiring the use of flash or strobe lighting to either compliment or completely eliminate the available ambient lighting. All the spaces captured at this higher level of detail were also captured with laser scanning. This allowed the team to validate the information and conduct a quality review of the photogrammetric data. As a result of this exercise, the team realized that in most, if not all cases, the photogrammetric data was more detailed and at a higher quality then the terrestrial laser scanning data. The purpose and motivation of this paper is to present these findings, as well provide the advantages and disadvantages of the two methods and data sets.

  20. CAPTURING REALITY AT CENTRE BLOCK

    Directory of Open Access Journals (Sweden)

    C. Boulanger

    2017-08-01

    Full Text Available The Centre Block of Canada’s Parliament buildings, National Historic Site of Canada is set to undergo a major rehabilitation project that will take approximately 10 years to complete. In preparation for this work, Heritage Conservation Services (HCS of Public Services and Procurement Canada has been completing heritage documentation of the entire site which includes laser scanning of all interior rooms and accessible confined spaces such as attics and other similar areas. Other documentation completed includes detailed photogrammetric documentation of rooms and areas of high heritage value. Some of these high heritage value spaces present certain challenges such as accessibility due to the height and the size of the spaces. Another challenge is the poor lighting conditions, requiring the use of flash or strobe lighting to either compliment or completely eliminate the available ambient lighting. All the spaces captured at this higher level of detail were also captured with laser scanning. This allowed the team to validate the information and conduct a quality review of the photogrammetric data. As a result of this exercise, the team realized that in most, if not all cases, the photogrammetric data was more detailed and at a higher quality then the terrestrial laser scanning data. The purpose and motivation of this paper is to present these findings, as well provide the advantages and disadvantages of the two methods and data sets.

  1. Splice variants of the relaxin and INSL3 receptors reveal unanticipated molecular complexity.

    Science.gov (United States)

    Muda, Marco; He, Chaomei; Martini, Paolo G V; Ferraro, Tania; Layfield, Sharon; Taylor, Deanne; Chevrier, Colette; Schweickhardt, Rene; Kelton, Christie; Ryan, Peter L; Bathgate, Ross A D

    2005-08-01

    LGR7 and LGR8 are G protein-coupled receptors that belong to the leucine-rich repeat-containing G-protein coupled receptor (LGR) family, including the thyroid-stimulating hormone (TSH), LH and FSH receptors. LGR7 and LGR8 stimulate cAMP production upon binding of the cognate ligands, relaxin and insulin-like peptide 3 (INSL3), respectively. We cloned several novel splice variants of both LGR7 and LGR8 and analysed the function of four variants. LGR7.1 is a truncated receptor, including only the N-terminal region of the receptor and two leucine rich repeats. In contrast, LGR7.2, LGR7.10 and LGR 8.1 all contain an intact seven transmembrane domain and most of the extracellular region, lacking only one or two exons in the ectodomain. Our analysis demonstrates that although LGR7.10 and LGR8.1 are expressed at the cell surface, LGR7.2 is predominantly retained within cells and LGR7.1 is partially secreted. mRNA expression analysis revealed that several variants are co-expressed in various tissues. None of these variants were able to stimulate cAMP production following relaxin or INSL3 treatment. Unexpectedly, we did not detect any direct specific relaxin or INSL3 binding on any of the splice variants. The large number of receptor splice variants identified suggests an unforeseen complexity in the physiology of this novel hormone-receptor system.

  2. Modification of nanofibrillated cellulose using amphiphilic block-structured galactoglucomannans.

    Science.gov (United States)

    Lozhechnikova, Alina; Dax, Daniel; Vartiainen, Jari; Willför, Stefan; Xu, Chunlin; Österberg, Monika

    2014-09-22

    Nanofibrillated cellulose (NFC) and hemicelluloses have shown to be highly promising renewable components both as barrier materials and in novel biocomposites. However, the hydrophilic nature of these materials restricts their use in some applications. In this work, the usability of modified O-acetyl galactoglucomannan (GGM) for modification of NFC surface properties was studied. Four GGM-block-structured, amphiphilic derivatives were synthesized using either fatty acids or polydimethylsiloxane as hydrophobic tails. The adsorption of these GGM derivatives was consecutively examined in aqueous solution using a quartz crystal microbalance with dissipation monitoring (QCM-D). It was found that the hydrophobic tails did not hinder adsorption of the GGM derivatives to cellulose, which was concluded to be due to the presence of the native GGM-block with high affinity to cellulose. The layer properties of the adsorbed block-co-polymers were discussed and evaluated. Self-standing NFC films were further prepared and coated with the GGM derivatives and the effect of the surface modification on wetting properties and oxygen permeability (OP) of the modified films was assessed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Bulk Vitrification Castable Refractory Block Protection Study

    Energy Technology Data Exchange (ETDEWEB)

    Hrma, Pavel R.; Bagaasen, Larry M.; Beck, Andrew E.; Brouns, Thomas M.; Caldwell, Dustin D.; Elliott, Michael L.; Matyas, Josef; Minister, Kevin BC; Schweiger, Michael J.; Strachan, Denis M.; Tinsley, Bronnie P.; Hollenberg, Glenn W.

    2005-05-01

    Bulk vitrification (BV) was selected for a pilot-scale test and demonstration facility for supplemental treatment to accelerate the cleanup of low-activity waste (LAW) at the Hanford U.S. DOE Site. During engineering-scale (ES) tests, a small fraction of radioactive Tc (and Re, its nonradioactive surrogate) were transferred out of the LAW glass feed and molten LAW glass, and deposited on the surface and within the pores of the castable refractory block (CRB). Laboratory experiments were undertaken to understand the mechanisms of the transport Tc/Re into the CRB during vitrification and to evaluate various means of CRB protection against the deposition of leachable Tc/Re. The tests used Re as a chemical surrogate for Tc. The tests with the baseline CRB showed that the molten LAW penetrates into CRB pores before it converts to glass, leaving deposits of sulfates and chlorides when the nitrate components decompose. Na2O from the LAW reacts with the CRB to create a durable glass phase that may contain Tc/Re. Limited data from a single CRB sample taken from an ES experiment indicate that, while a fraction of Tc/Re is present in the CRB in a readily leachable form, most of the Tc/Re deposited in the refractory is retained in the form of a durable glass phase. In addition, the molten salts from the LAW, mainly sulfates, chlorides, and nitrates, begin to evaporate from BV feeds at temperatures below 800 C and condense on solid surfaces at temperatures below 530 C. Three approaches aimed at reducing or preventing the deposition of soluble Tc/Re within the CRB were proposed: metal lining, sealing the CRB surface with a glaze, and lining the CRB with ceramic tiles. Metal liners were deemed unsuitable because evaluations showed that they can cause unacceptable distortions of the electric field in the BV system. Sodium silicate and a low-alkali borosilicate glaze were selected for testing. The glazes slowed down molten salt condensate penetration, but did little to reduce the

  4. Polymorphic Ring-Shaped Molecular Clusters Made of Shape-Variable Building Blocks

    Directory of Open Access Journals (Sweden)

    Keitel Cervantes-Salguero

    2015-02-01

    Full Text Available Self-assembling molecular building blocks able to dynamically change their shapes, is a concept that would offer a route to reconfigurable systems. Although simulation studies predict novel properties useful for applications in diverse fields, such kinds of building blocks, have not been implemented thus far with molecules. Here, we report shape-variable building blocks fabricated by DNA self-assembly. Blocks are movable enough to undergo shape transitions along geometrical ranges. Blocks connect to each other and assemble into polymorphic ring-shaped clusters via the stacking of DNA blunt-ends. Reconfiguration of the polymorphic clusters is achieved by the surface diffusion on mica substrate in response to a monovalent salt concentration. This work could inspire novel reconfigurable self-assembling systems for applications in molecular robotics.

  5. Comparative study between ultrasound guided tap block and paravertebral block in upper abdominal surgeries. Randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Ruqaya M. Elsayed

    2017-01-01

    Conclusion: We concluded that ultrasound guided transversus abdominis plane block and thoracic paravertebral block were safe and effective anesthetic technique for upper abdominal surgery with longer and potent postoperative analgesia in thoracic paravertebral block than transversus abdominis block.

  6. Annotating pathogenic non-coding variants in genic regions.

    Science.gov (United States)

    Gelfman, Sahar; Wang, Quanli; McSweeney, K Melodi; Ren, Zhong; La Carpia, Francesca; Halvorsen, Matt; Schoch, Kelly; Ratzon, Fanni; Heinzen, Erin L; Boland, Michael J; Petrovski, Slavé; Goldstein, David B

    2017-08-09

    Identifying the underlying causes of disease requires accurate interpretation of genetic variants. Current methods ineffectively capture pathogenic non-coding variants in genic regions, resulting in overlooking synonymous and intronic variants when searching for disease risk. Here we present the Transcript-inferred Pathogenicity (TraP) score, which uses sequence context alterations to reliably identify non-coding variation that causes disease. High TraP scores single out extremely rare variants with lower minor allele frequencies than missense variants. TraP accurately distinguishes known pathogenic and benign variants in synonymous (AUC = 0.88) and intronic (AUC = 0.83) public datasets, dismissing benign variants with exceptionally high specificity. TraP analysis of 843 exomes from epilepsy family trios identifies synonymous variants in known epilepsy genes, thus pinpointing risk factors of disease from non-coding sequence data. TraP outperforms leading methods in identifying non-coding variants that are pathogenic and is therefore a valuable tool for use in gene discovery and the interpretation of personal genomes.While non-coding synonymous and intronic variants are often not under strong selective constraint, they can be pathogenic through affecting splicing or transcription. Here, the authors develop a score that uses sequence context alterations to predict pathogenicity of synonymous and non-coding genetic variants, and provide a web server of pre-computed scores.

  7. [Construction of haplotype and haplotype block based on tag single nucleotide polymorphisms and their applications in association studies].

    Science.gov (United States)

    Gu, Ming-liang; Chu, Jia-you

    2007-12-01

    Human genome has structures of haplotype and haplotype block which provide valuable information on human evolutionary history and may lead to the development of more efficient strategies to identify genetic variants that increase susceptibility to complex diseases. Haplotype block can be divided into discrete blocks of limited haplotype diversity. In each block, a small fraction of ptag SNPsq can be used to distinguish a large fraction of the haplotypes. These tag SNPs can be potentially useful for construction of haplotype and haplotype block, and association studies in complex diseases. There are two general classes of methods to construct haplotype and haplotype blocks based on genotypes on large pedigrees and statistical algorithms respectively. The author evaluate several construction methods to assess the power of different association tests with a variety of disease models and block-partitioning criteria. The advantages, limitations and applications of each method and the application in the association studies are discussed equitably. With the completion of the HapMap and development of statistical algorithms for addressing haplotype reconstruction, ideas of construction of haplotype based on combination of mathematics, physics, and computer science etc will have profound impacts on population genetics, location and cloning for susceptible genes in complex diseases, and related domain with life science etc.

  8. Microsatellite Instability Use in Mismatch Repair Gene Sequence Variant Classification

    Directory of Open Access Journals (Sweden)

    Bryony A. Thompson

    2015-03-01

    Full Text Available Inherited mutations in the DNA mismatch repair genes (MMR can cause MMR deficiency and increased susceptibility to colorectal and endometrial cancer. Microsatellite instability (MSI is the defining molecular signature of MMR deficiency. The clinical classification of identified MMR gene sequence variants has a direct impact on the management of patients and their families. For a significant proportion of cases sequence variants of uncertain clinical significance (also known as unclassified variants are identified, constituting a challenge for genetic counselling and clinical management of families. The effect on protein function of these variants is difficult to interpret. The presence or absence of MSI in tumours can aid in determining the pathogenicity of associated unclassified MMR gene variants. However, there are some considerations that need to be taken into account when using MSI for variant interpretation. The use of MSI and other tumour characteristics in MMR gene sequence variant classification will be explored in this review.

  9. Simulation study of the effect of differences in block energy and density on the self-assembly of block copolymers

    Science.gov (United States)

    Lawson, Richard A.; Peters, Andrew J.; Nation, Benjamin; Ludovice, Peter J.; Henderson, Clifford L.

    2014-03-01

    from ones simulated using equivalent densities and cohesive energy densities. The lowest CED block has a strong propensity to segregate to and "wet" the free interface at the top of the film because it has the lowest energy penalty for the loss of interactions with other chains at the free surface relative to the bulk. This gives rise to an effective "skinning" of the film by the lowest CED block for almost the entire potential range of underlayer compositions and film thicknesses. Such materials will be extremely difficult to successfully pattern transfer for a lithographically useful process because they will not form vertically aligned morphologies through the entire film thickness. This CED mismatch also gives rise to a large number of non-bulk morphologies and deviations from bulk behavior including changing vertical-to-horizontal morphologies through film depth, compression and expansion of domain sizes to match film thickness dimensions, and island and hole formation among others. Increasing the χN value can potentially suppress some of these non-idealities due to CED asymmetry, but the required χN to overcome these issues will differ from polymer to polymer depending on the magnitude of the CED asymmetry.

  10. Ionization of amphiphilic acidic block copolymers.

    Science.gov (United States)

    Colombani, Olivier; Lejeune, Elise; Charbonneau, Céline; Chassenieux, Christophe; Nicolai, Taco

    2012-06-28

    The ionization behavior of an amphiphilic diblock copolymer poly(n-butyl acrylate(50%)-stat-acrylic acid(50%))(100)-block-poly(acrylic acid)(100) (P(nBA(50%)-stat-AA(50%))(100)-b-PAA(100), DH50) and of its equivalent triblock copolymer P(nBA(50%)-stat-AA(50%))(100)-b-PAA(200)-b-P(nBA(50%)-stat-AA(50%))(100) (TH50) were studied by potentiometric titration either in pure water or in 0.5 M NaCl. These polymers consist of a hydrophilic acidic block (PAA) connected to a hydrophobic block, P(nBA(50%)-stat-AA(50%))(100), whose hydrophobic character has been mitigated by copolymerization with hydrophilic units. We show that all AA units, even those in the hydrophobic block could be ionized. However, the AA units within the hydrophobic block were less acidic than those in the hydrophilic block, resulting in the preferential ionization of the latter block. The preferential ionization of PAA over that of P(nBA(50%)-stat-AA(50%))(100) was stronger at higher ionic strength. Remarkably, the covalent bonds between the PAA and P(nBA(50%)-stat-AA(50%))(100) blocks in the diblock or the triblock did not affect the ionization of each block, although the self-association of the block copolymers into spherical aggregates modified the environment of the PAA blocks compared to when PAA was molecularly dispersed.

  11. Nanostructured Polysulfone-Based Block Copolymer Membranes

    KAUST Repository

    Xie, Yihui

    2016-05-01

    The aim of this work is to fabricate nanostructured membranes from polysulfone-based block copolymers through self-assembly and non-solvent induced phase separation. Block copolymers containing polysulfone are novel materials for this purpose providing better mechanical and thermal stability to membranes than polystyrene-based copolymers, which have been exclusively used now. Firstly, we synthesized a triblock copolymer, poly(tert-butyl acrylate)-b-polsulfone-b-poly(tert-butyl acrylate) through polycondensation and reversible addition-fragmentation chain-transfer polymerization. The obtained membrane has a highly porous interconnected skin layer composed of elongated micelles with a flower-like arrangement, on top of the graded finger-like macrovoids. Membrane surface hydrolysis was carried out in a combination with metal complexation to obtain metal-chelated membranes. The copper-containing membrane showed improved antibacterial capability. Secondly, a poly(acrylic acid)-b-polysulfone-b-poly(acrylic acid) triblock copolymer obtained by hydrolyzing poly(tert-butyl acrylate)-b-polsulfone-b-poly(tert-butyl acrylate) formed a thin film with cylindrical poly(acrylic acid) microdomains in polysulfone matrix through thermal annealing. A phase inversion membrane was prepared from the same polymer via self-assembly and chelation-assisted non-solvent induced phase separation. The spherical micelles pre-formed in a selective solvent mixture packed into an ordered lattice in aid of metal-poly(acrylic acid) complexation. The space between micelles was filled with poly(acrylic acid)-metal complexes acting as potential water channels. The silver0 nanoparticle-decorated membrane was obtained by surface reduction, having three distinct layers with different particle sizes. Other amphiphilic copolymers containing polysulfone and water-soluble segments such as poly(ethylene glycol) and poly(N-isopropylacrylamide) were also synthesized through coupling reaction and copper0-mediated

  12. Melanoma risk associated with MC1R gene variants in Latvia and the functional analysis of rare variants.

    Science.gov (United States)

    Ozola, Aija; Azarjana, Kristīne; Doniņa, Simona; Proboka, Guna; Mandrika, Ilona; Petrovska, Ramona; Cēma, Ingrīda; Heisele, Olita; Eņģele, Ludmila; Streinerte, Baiba; Pjanova, Dace

    2013-03-01

    To evaluate the association of melanocortin 1 receptor gene (MC1R) variants with melanoma risk in a Latvian population, the MC1R gene was sequenced in 200 melanoma patients and 200 control persons. A functional study of previously uncharacterized, rare MC1R variants was also performed. In total, 26 different MC1R variants, including two novel variants Val165Ile and Val188Ile, were detected. The highest risk of melanoma was associated with the Arg151Cys variant (odds ratio (OR) 4.47, 95% confidence interval (CI) 2.19-9.14, PLatvia. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Approximate design theory for a simple block design with random block effects

    OpenAIRE

    Christof, Karin

    1985-01-01

    Approximate design theory for a simple block design with random block effects / K. Christof ; F. Pukelsheim. - In: Linear statistical inference / ed. by T. Calinski ... - Berlin u. a. : Springer, 1985. - S. 20-28. - (Lecture notes in statistics ; 35)

  14. Micellar aggregates of amylose-block-polystyrene rod-coil block copolymers in water and THF

    NARCIS (Netherlands)

    Loos, Katja; Böker, Alexander; Zettl, Heiko; Zhang, Mingfu; Krausch, Georg; Müller, Axel H.E.; Boker, A.; Zhang, A.F.

    2005-01-01

    Amylose-block-polystyrenes with various block copolymer compositions were investigated in water and in THF solution. Fluorescence correlation spectroscopy, dynamic light, scattering (DLS), and asymmetric flow field-flow fractionation with multiangle light scattering detection indicate the presence

  15. Development of connecting method for mechanically cut reinforced concrete blocks

    International Nuclear Information System (INIS)

    Nishiuchi, Tatsuo

    2005-01-01

    The purpose of the study is to develop a practical method of disposing and recycling in dismantled reinforced concrete structures. We have devised a new method in which mechanically cut reinforced concrete blocks are connected and they are reused as a structural beam. In this method, concrete blocks are connected with several steel bars and the connected surface is wrapped with a fiber sheet. We verified that the load capacity of renewal beams was considerably large as same as that of continuous structural beams on the basis of experimental as well as numerical analysis results. As far as construction cost of reinforced concrete walls are concerned, we demonstrated that the cost of this method is slightly lower than that of the plan to use new and recycle materials. (author)

  16. Magnetic Alignment of Block Copolymer Microdomains by Intrinsic Chain Anisotropy.

    Science.gov (United States)

    Rokhlenko, Yekaterina; Gopinadhan, Manesh; Osuji, Chinedum O; Zhang, Kai; O'Hern, Corey S; Larson, Steven R; Gopalan, Padma; Majewski, Paweł W; Yager, Kevin G

    2015-12-18

    We examine the role of intrinsic chain susceptibility anisotropy in magnetic field directed self-assembly of a block copolymer using in situ x-ray scattering. Alignment of a lamellar mesophase is observed on cooling across the disorder-order transition with the resulting orientational order inversely proportional to the cooling rate. We discuss the origin of the susceptibility anisotropy, Δχ, that drives alignment and calculate its magnitude using coarse-grained molecular dynamics to sample conformations of surface-tethered chains, finding Δχ≈2×10^{-8}. From field-dependent scattering data, we estimate that grains of ≈1.2  μm are present during alignment. These results demonstrate that intrinsic anisotropy is sufficient to support strong field-induced mesophase alignment and suggest a versatile strategy for field control of orientational order in block copolymers.

  17. Conservation analysis of dengue virus T-cell epitope-based vaccine candidates using peptide block entropy

    Directory of Open Access Journals (Sweden)

    Lars Ronn Olsen

    2011-12-01

    Full Text Available Broad coverage of the pathogen population is particularly important when designing CD8+ T-cell epitope vaccines against viral pathogens. Traditional approaches to assembling broadly covering sets of peptides are commonly based on assembling highly conserved epitopes. Peptide block entropy analysis is a novel approach to assembling sets of broadly covering antigens. Since T-cell epitopes are recognized as peptides rather than individual residues, this method is based on calculating the information content of blocks of peptides from a multiple sequence alignment of homologous proteins rather than individual residues. The block entropy analysis provides broad coverage by variant inclusion, since high frequency may not be the sole determinant of the immunogenic potential of a predicted MHC class I binder. We applied block entropy analysis method to the proteomes of the four serotypes of dengue virus and found 1,551 blocks of 9-mer peptides, which covered all available sequences with five or fewer unique peptides. In contrast, the benchmark study by Khan et al. (2008, resulted in 165 9-mers being determined as conserved. Many of the blocks are located consecutively in the proteins, so connecting these blocks resulted in 78 conserved regions which can be covered with 457 subunit peptides. Of the 1551 blocks of 9-mer peptides, 110 blocks consisted of peptides all predicted to bind to MHC with similar affinity and the same HLA restriction. In total, we identified a pool of 333 peptides as T-cell epitope candidates. This set could form the basis for a broadly neutralizing dengue virus vaccine. The peptide block entropy analysis approach significantly increases the number of conserved peptide regions in comparison to traditional conservation analysis of individual residues. We determined 457 subunit peptides with the capacity to encompass the diversity of all sequenced DENV strains.

  18. Substrate tolerant direct block copolymer nanolithography

    DEFF Research Database (Denmark)

    Li, Tao; Wang, Zhongli; Schulte, Lars

    2016-01-01

    Block copolymer (BC) self-assembly constitutes a powerful platform for nanolithography. However, there is a need for a general approach to BC lithography that critically considers all the steps from substrate preparation to the final pattern transfer. We present a procedure that significantly...... plasma treatment enables formation of the oxidized PDMS hard mask, PS block removal and polymer or graphene substrate patterning....

  19. Pixel Decimation in Block Matching Techniques

    Directory of Open Access Journals (Sweden)

    D. Levicky

    2000-12-01

    Full Text Available Block motion estimation using full search algorithm is computationallyextensive. Previously proposed fast algorithms reduce the computationcost by limiting the number of locations searched. In this paper wepresent algorithms for block motion estimation that produce similarperformance to that full search algorithm. The algorithms are based onthe pixel decimation.

  20. Block Gas Sol Unit in Haderslev

    DEFF Research Database (Denmark)

    Vejen, Niels Kristian

    2000-01-01

    Investigation of a SDHW system based on a Block Gas Sol Unit from Baxi A/S installed by a consumer i Haderslev, Denmark.......Investigation of a SDHW system based on a Block Gas Sol Unit from Baxi A/S installed by a consumer i Haderslev, Denmark....

  1. CONJUGATED BLOCK-COPOLYMERS FOR ELECTROLUMINESCENT DIODES

    NARCIS (Netherlands)

    Hilberer, A; Gill, R.E; Herrema, J.K; Malliaras, G.G; Wildeman, J.; Hadziioannou, G

    In this article we review results obtained in our laboratory on the design and study of new light-emitting polymers. We are interested in the synthesis and characterisation of block copolymers with regularly alternating conjugated and non conjugated sequences. The blocks giving rise to luminescence

  2. C++ application development with Code::Blocks

    CERN Document Server

    Modak, Biplab Kumar

    2013-01-01

    This is a comprehensive tutorial with step-by-step instructions on how to develop applications with Code::Blocks.This book is for C++ developers who wish to use Code::Blocks to create applications with a consistent look and feel across multiple platforms. This book assumes that you are familiar with the basics of the C++ programming language.

  3. PEO-related block copolymer surfactants

    DEFF Research Database (Denmark)

    Mortensen, K.

    2001-01-01

    Non-ionic block copolymer systems based on hydrophilic poly(ethylene oxide) and more hydrophobic co-polymer blocks are used intensively in a variety of industrial and personal applications. A brief description on the applications is presented. The physical properties of more simple model systems ...

  4. Benchmarking Block Ciphers for Wireless Sensor Networks

    NARCIS (Netherlands)

    Law, Y.W.; Doumen, J.M.; Hartel, Pieter H.

    2004-01-01

    Choosing the most storage- and energy-efficient block cipher specifically for wireless sensor networks (WSNs) is not as straightforward as it seems. To our knowledge so far, there is no systematic evaluation framework for the purpose. We have identified the candidates of block ciphers suitable for

  5. The Cognitive Dimension of Writer's Block.

    Science.gov (United States)

    Rose, Mike

    A study investigated cognitive behaviors and processes that contribute to writer's block. Subjects were 10 college undergraduates who had scored at the extreme ends of a writer's block measurement instrument. The 10, 6 "high-blockers" and 4 "low-blockers," varied in their English experience, class standing, and majors. Each was given a writing…

  6. Programs for the calculi of blocks permeabilities

    International Nuclear Information System (INIS)

    Gomez Hernandez, J.J.; Sovero Sovero, H.F.

    1993-01-01

    This report studies the stochastic analysis of radionuclide transport. The permeability values of blocks are necessary to do a numeric model for the flux and transport problems in ground soils. The determination of block value by function on grill value is the objective of this program

  7. Micellization and Characterization of Block Copolymer Detergents

    DEFF Research Database (Denmark)

    Hvidt, Søren

    Triblock copolymers of the type EPE, where E and P denote ethylene oxide and propylene oxide blocks, respectively, are used widely in industry as emulsifiers, anti-foaming agents, and in delayed drug release. EPE copolymers form micelles with a core of P blocks and different micellar shapes depen...

  8. Blending of styrene-block-butadiene-block-styrene copolymer with sulfonated vinyl aromatic polymers

    OpenAIRE

    Ruggeri, Giacomo; Passaglia, Elisa; Giorgi, Ivan; Picchioni, Francesco; Aglietto, Mauro

    2001-01-01

    Different polymers containing sulfonic groups attached to the phenyl rings were prepared by sulfonation of polystyrene (PS) and styrene-block-(ethylene-co-1-butene)-block-styrene (SEBS). The sulfonation degree (SD) was varied between 1 and 20 mol% of the styrene units. Polyphase materials containing sulfonated units were prepared by blending styrene-block-butadiene-block-styrene (SBS), with both sulfonated PS and sulfonated SEBS in a Brabender mixer. Such a procedure was performed as an alter...

  9. Right bundle branch block pattern during right ventricular permanent pacing: Is it safe or not?

    OpenAIRE

    Erdogan, Okan; Aksu, Feyza

    2007-01-01

    The present case report describes a patient with dual chamber pacemaker whose surface ECG demonstrated paced right bundle branch block pattern suggesting a malpositioned ventricular lead in the left ventricle. However, diagnostic work-up revealed that the lead was appropriately located in the right ventricular apex. Diagnostic maneuvers and clues for differentiating safe right bundle branch block pattern during permanent pacing are thoroughly revisited and discussed within the article.

  10. Variants of the xeroderma pigmentosum variant gene (POLH) are associated with melanoma risk.

    Science.gov (United States)

    Di Lucca, Julie; Guedj, Mickael; Lacapère, Jean-Jacques; Fargnoli, Maria Concetta; Bourillon, Agnes; Dieudé, Philippe; Dupin, Nicolas; Wolkenstein, Pierre; Aegerter, Philippe; Saiag, Philippe; Descamps, Vincent; Lebbe, Celeste; Basset-Seguin, Nicole; Peris, Ketty; Grandchamp, Bernard; Soufir, Nadem

    2009-12-01

    Xeroderma pigmentosum variant (XPV) is a rare recessive autosomal genodermatosis predisposing to multiple early onset skin cancers, including melanoma. XPV results from mutations of the POLH gene that encodes a DNA translesion polymerase. In this work, we tested the hypothesis that POLH variants could be associated with melanoma risk. A common non-synonymous POLH variant, c.1783A>G p.M595V, was genotyped in 1075 melanoma patients and in 1091 ethnic-matched controls from France. In addition, we searched for rare POLH variants by sequencing the entire coding sequence in 201 patients having a familial history of melanoma (n=123), sporadic multiple melanomas (n=65) and a melanoma associated with a skin carcinoma (n=13). Overall, the c.1783G, p.595V allele was statistically associated with melanoma (respective allelic frequencies, 0.040 versus 0.022, P-value=1.17 x 10(-3), odds ratio (OR)=1.86 [1.27-2.71]), which was further confirmed by a meta-analysis including 274 patients and 174 matched controls from Italy (P-value=7.7 x 10(-4), OR=1.84 [1.29-2.63]). Interestingly, three non-synonymous POLH variants were identified in three patients (c.295G>A p.V99M, c.815T>C p.I272T and c.1745C>T p.S582L) which were absent in 352 chromosome controls from healthy subjects. Besides severe deficiencies in translesion synthesis which are major risks factors for skin carcinomas and melanomas, less deleterious POLH variants could act as low penetrance melanoma predisposing alleles. The ongoing identification of genetic markers implied in skin cancer predisposition could help to identify high-risk subjects as targets for clinical follow-up. Replication studies in other populations are awaited to assess these data.

  11. Block information and topology in memory networks

    Science.gov (United States)

    Dominguez, David

    2007-02-01

    The retrieval abilities of spatially uniform attractor networks can be measured by the average overlap between patterns and neural states. Metric networks (with local connections), like small-world graphs, modelled by the parameters: connectivity γ and randomness ω, however, display a richer distribution of memory attractors. We found that metric networks can carry information structured in blocks without any global overlap. There is a competition between global and blocks attractors. We propose a way to measure the block information, related to the fluctuations of the overlap over the blocks. The phase-diagram with the transition from local to global information, shows that the stability of blocks grows with dilution, but decreases with the storage rate and disappears for random topologies.

  12. [Establishment of delta block matching technique].

    Science.gov (United States)

    Lü, Qin-Feng; Zhang, Wei; Zhu, Fa-Ming; Yan, Li-Xing

    2006-04-01

    To establish delta block HLA-matching technique, DNA was extracted from whole blood by salting-out method, delta block was amplified by polymerase chain reaction (PCR), and PCR product was detected by GeneScan. The results showed that delta block had polymorphism in 104 samples without sibship of the Han people from Zhejiang province. The range of DNA fragment length was 81-393 bp and could be divided into 4 groups: 81-118 bp, 140-175 bp, 217-301 bp, 340-393 bp. The numbers of DNA fragments were 6-32. It is concluded that the method of delta block matching is reliable and can be applied to select donors for the patients to be transplanted. It is the first time to get delta block data of the Han people in China.

  13. The undesirable effects of neuromuscular blocking drugs

    DEFF Research Database (Denmark)

    Claudius, C; Garvey, L H; Viby-Mogensen, J

    2009-01-01

    Neuromuscular blocking drugs are designed to bind to the nicotinic receptor at the neuromuscular junction. However, they also interact with other acetylcholine receptors in the body. Binding to these receptors causes adverse effects that vary with the specificity for the cholinergic receptor...... in question. Moreover, all neuromuscular blocking drugs may cause hypersensitivity reactions. Often the symptoms are mild and self-limiting but massive histamine release can cause systematic reactions with circulatory and respiratory symptoms and signs. At the end of anaesthesia, no residual effect...... of a neuromuscular blocking drug should be present. However, the huge variability in response to neuromuscular blocking drugs makes it impossible to predict which patient will suffer postoperative residual curarization. This article discusses the undesirable effects of the currently available neuromuscular blocking...

  14. Syncope and Idiopathic (Paroxysmal) AV Block.

    Science.gov (United States)

    Brignole, Michele; Deharo, Jean-Claude; Guieu, Regis

    2015-08-01

    Syncope due to idiopathic AV block is characterized by: 1) ECG documentation (usually by means of prolonged ECG monitoring) of paroxysmal complete AV block with one or multiple consecutive pauses, without P-P cycle lengthening or PR interval prolongation, not triggered by atrial or ventricular premature beats nor by rate variations; 2) long history of recurrent syncope without prodromes; 3) absence of cardiac and ECG abnormalities; 4) absence of progression to persistent forms of AV block; 5) efficacy of cardiac pacing therapy. The patients affected by idiopathic AV block have low baseline adenosine plasma level values and show an increased susceptibility to exogenous adenosine. The APL value of the patients with idiopathic AV block is much lower than patients affected by vasovagal syncope who have high adenosine values. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Block copolymer structures in nano-pores

    Science.gov (United States)

    Pinna, Marco; Guo, Xiaohu; Zvelindovsky, Andrei

    2010-03-01

    We present results of coarse-grained computer modelling of block copolymer systems in cylindrical and spherical nanopores on Cell Dynamics Simulation. We study both cylindrical and spherical pores and systematically investigate structures formed by lamellar, cylinders and spherical block copolymer systems for various pore radii and affinity of block copolymer blocks to the pore walls. The obtained structures include: standing lamellae and cylinders, ``onions,'' cylinder ``knitting balls,'' ``golf-ball,'' layered spherical, ``virus''-like and mixed morphologies with T-junctions and U-type defects [1]. Kinetics of the structure formation and the differences with planar films are discussed. Our simulations suggest that novel porous nano-containers can be formed by confining block copolymers in pores of different geometries [1,2]. [4pt] [1] M. Pinna, X. Guo, A.V. Zvelindovsky, Polymer 49, 2797 (2008).[0pt] [2] M. Pinna, X. Guo, A.V. Zvelindovsky, J. Chem. Phys. 131, 214902 (2009).

  16. Sympathetic blocks for visceral cancer pain management

    DEFF Research Database (Denmark)

    Mercadante, Sebastiano; Klepstad, Pal; Kurita, Geana Paula

    2015-01-01

    The neurolytic blocks of sympathetic pathways, including celiac plexus block (CPB) and superior hypogastric plexus block (SHPB) , have been used for years. The aim of this review was to assess the evidence to support the performance of sympathetic blocks in cancer patients with abdominal visceral...... pain. Only comparison studies were included. All data from the eligible trials were analyzed using the GRADE system. Twenty-seven controlled studies were considered. CPB, regardless of the technique used, improved analgesia and/or decrease opioid consumption, and decreased opioid-induced adverse...... effects in comparison with a conventional analgesic treatment. In one study patients treated with superior hypogastric plexus block (SHPB) had a decrease in pain intensity and a less morphine consumption, while no statistical differences in adverse effects were found. The quality of these studies...

  17. 31 CFR 542.204 - Expenses of maintaining blocked property; liquidation of blocked property.

    Science.gov (United States)

    2010-07-01

    ... property; liquidation of blocked property. 542.204 Section 542.204 Money and Finance: Treasury Regulations... SYRIAN SANCTIONS REGULATIONS Prohibitions § 542.204 Expenses of maintaining blocked property; liquidation of blocked property. (a) Except as otherwise authorized, and notwithstanding the existence of any...

  18. 31 CFR 548.204 - Expenses of maintaining blocked physical property; liquidation of blocked property.

    Science.gov (United States)

    2010-07-01

    ... physical property; liquidation of blocked property. 548.204 Section 548.204 Money and Finance: Treasury... property; liquidation of blocked property. (a) Except as otherwise authorized, and notwithstanding the... maintenance of physical property blocked pursuant to § 548.201(a) shall be the responsibility of the owners or...

  19. 31 CFR 537.209 - Expenses of maintaining blocked property; liquidation of blocked account.

    Science.gov (United States)

    2010-07-01

    ... property; liquidation of blocked account. 537.209 Section 537.209 Money and Finance: Treasury Regulations... BURMESE SANCTIONS REGULATIONS Prohibitions § 537.209 Expenses of maintaining blocked property; liquidation... the maintenance of physical property blocked pursuant to § 537.201(a) shall be the responsibility of...

  20. 31 CFR 594.206 - Expenses of maintaining blocked property; liquidation of blocked property.

    Science.gov (United States)

    2010-07-01

    ... property; liquidation of blocked property. 594.206 Section 594.206 Money and Finance: Treasury Regulations... GLOBAL TERRORISM SANCTIONS REGULATIONS Prohibitions § 594.206 Expenses of maintaining blocked property; liquidation of blocked property. (a) Except as otherwise authorized, and notwithstanding the existence of any...

  1. 31 CFR 543.204 - Expenses of maintaining blocked physical property; liquidation of blocked property.

    Science.gov (United States)

    2010-07-01

    ... physical property; liquidation of blocked property. 543.204 Section 543.204 Money and Finance: Treasury... physical property; liquidation of blocked property. (a) Except as otherwise authorized, and notwithstanding... to the maintenance of physical property blocked pursuant to § 543.201(a) shall be the responsibility...

  2. 31 CFR 541.205 - Expenses of maintaining blocked property; liquidation of blocked account.

    Science.gov (United States)

    2010-07-01

    ... property; liquidation of blocked account. 541.205 Section 541.205 Money and Finance: Treasury Regulations... ZIMBABWE SANCTIONS REGULATIONS Prohibitions § 541.205 Expenses of maintaining blocked property; liquidation... maintenance of physical property blocked pursuant to § 541.201(a) shall be the responsibility of the owners or...

  3. 31 CFR 546.204 - Expenses of maintaining blocked physical property; liquidation of blocked property.

    Science.gov (United States)

    2010-07-01

    ... physical property; liquidation of blocked property. 546.204 Section 546.204 Money and Finance: Treasury... property; liquidation of blocked property. (a) Except as otherwise authorized, and notwithstanding the... maintenance of physical property blocked pursuant to § 546.201(a) shall be the responsibility of the owners or...

  4. 31 CFR 588.205 - Expenses of maintaining blocked property; liquidation of blocked account.

    Science.gov (United States)

    2010-07-01

    ... property; liquidation of blocked account. 588.205 Section 588.205 Money and Finance: Treasury Regulations... WESTERN BALKANS STABILIZATION REGULATIONS Prohibitions § 588.205 Expenses of maintaining blocked property; liquidation of blocked account. (a) Except as otherwise authorized, and notwithstanding the existence of any...

  5. 31 CFR 545.207 - Expenses of maintaining blocked property; liquidation of blocked account.

    Science.gov (United States)

    2010-07-01

    ... property; liquidation of blocked account. 545.207 Section 545.207 Money and Finance: Treasury Regulations... property; liquidation of blocked account. (a) Except as otherwise authorized, and notwithstanding the... expenses incident to the maintenance of physical property blocked pursuant to § 545.201 shall be the...

  6. Plume-induced dynamic instabilities near cratonic blocks: Implications for P-T-t paths and metallogeny

    NARCIS (Netherlands)

    Guillou-Frottier, L.; Burov, E.; Cloetingh, S.; Le Goff, E.; Deschamps, Y.; Huet, B.; Bouchot, V.

    2012-01-01

    Plume head - lithosphere interactions around cratonic blocks result in thermo-mechanical disturbances that lead to heating and burial phases of crustal rocks. We present results from numerical models of plume head - cratonic blocks interactions where a free upper surface condition and realistic

  7. The combined compression and shear of a rectangular rubber block

    Science.gov (United States)

    Hill, James M.; Myers, Timothy G.

    1992-09-01

    For long rectangular rubber blocks with metal plates bonded to their upper and lower surfaces, approximate force-deflection relations are obtained for the problem of combined compression (or tension) and shear. The results obtained generalise that of Klingbeil and Shield for the case of pure compression alone, as well as incorporating the well known simple shear result. However, unlike the pure compression solution, horizontal and vertical force resultants on the free surfaces cannot both be set to zero, which is a well known characteristic of simple shearing. Here the strategy is adopted of equating to zero only the horizontal force resultants on the free surfaces so that the pure compression approximation of Klingbeil and Shield emerges in the event of zero shear. The force-deflection relations so obtained are illustrated graphically.

  8. Aligned nanowires and nanodots by directed block copolymer assembly

    Science.gov (United States)

    Xiao, Shuaigang; Yang, XiaoMin; Lee, Kim Y.; ver der Veerdonk, Rene J. M.; Kuo, David; Russell, Thomas P.

    2011-07-01

    The directed self-assembly of block copolymers (BCPs) is a promising route to generate highly ordered arrays of sub-10 nm features. Ultradense arrays of a monolayer of spherical microdomains or cylindrical microdomains oriented parallel to the surface have been produced where the lateral ordering is guided by surface patterning and the lattice defined by the patterning can be commensurate or incommensurate with the natural period of the BCP. Commensurability between the two can be used to elegantly manipulate the lateral ordering and orientation of the BCP microdomains so as to form well-aligned arrays of 1D nanowires or 2D addressable nanodots. No modification of the substrate surface, aside from the patterning, was used, making the influence of lattice mismatch and pattern amplification on the size, shape and pitch of the BCP microdomains more transparent. A skew angle between incommensurate lattices, defining a stretching or compression of the BCP chains to compensate for the lattice mismatch, is presented.

  9. The rapid cooling of the Nansha Block, southern South China Sea

    Science.gov (United States)

    Dong, M.; Zhang, J.

    2017-12-01

    Since the Late Cretaceous and Cenozoic, the Nansha Block has experienced a series of tectonic process and separated from South China continent to the south. As an exotic micro-continental, Nansha Block has an obvious different lithospheric rheology property from surrounding region. The lithosphere and mantle dynamic and rheology are mainly controlled by temperature. Therefore, we calculated the 3D temperature field and geothermal gradient of Nansha Block's upper mantle by using the S-wave velocity structure from surface wave tomography. The results show that the depth where temperature of 1300° as the lithospheric thickness is in close correspondence with the top of the seismic low velocity zone. The temperature of the upper mantle in Nansha Block is significantly lower than that of surrounding. It implies that Nansha Block experienced a rapid cooling event. We propose that the rapid cooling can be partly attributed to three reasons: 1) Nansha Block is a relatively stable block with no interior geothermal activity. 2) No external heat source to provide energy. 3) Abnormal mantle convection under Nansha Block accelerated the cooling.

  10. Automation of block assignment planning using a diagram-based scenario modeling method

    Science.gov (United States)

    Hwang, In Hyuck; Kim, Youngmin; Lee, Dong Kun; Shin, Jong Gye

    2014-03-01

    Most shipbuilding scheduling research so far has focused on the load level on the dock plan. This is be¬cause the dock is the least extendable resource in shipyards, and its overloading is difficult to resolve. However, once dock scheduling is completed, making a plan that makes the best use of the rest of the resources in the shipyard to minimize any additional cost is also important. Block assignment planning is one of the midterm planning tasks; it assigns a block to the facility (factory/shop or surface plate) that will actually manufacture the block according to the block characteristics and current situation of the facility. It is one of the most heavily loaded midterm planning tasks and is carried out manu¬ally by experienced workers. In this study, a method of representing the block assignment rules using a diagram was su¬ggested through analysis of the existing manual process. A block allocation program was developed which automated the block assignment process according to the rules represented by the diagram. The planning scenario was validated through a case study that compared the manual assignment and two automated block assignment results.

  11. Genetic Variants Associated with Circulating Parathyroid Hormone.

    Science.gov (United States)

    Robinson-Cohen, Cassianne; Lutsey, Pamela L; Kleber, Marcus E; Nielson, Carrie M; Mitchell, Braxton D; Bis, Joshua C; Eny, Karen M; Portas, Laura; Eriksson, Joel; Lorentzon, Mattias; Koller, Daniel L; Milaneschi, Yuri; Teumer, Alexander; Pilz, Stefan; Nethander, Maria; Selvin, Elizabeth; Tang, Weihong; Weng, Lu-Chen; Wong, Hoi Suen; Lai, Dongbing; Peacock, Munro; Hannemann, Anke; Völker, Uwe; Homuth, Georg; Nauk, Matthias; Murgia, Federico; Pattee, Jack W; Orwoll, Eric; Zmuda, Joseph M; Riancho, Jose Antonio; Wolf, Myles; Williams, Frances; Penninx, Brenda; Econs, Michael J; Ryan, Kathleen A; Ohlsson, Claes; Paterson, Andrew D; Psaty, Bruce M; Siscovick, David S; Rotter, Jerome I; Pirastu, Mario; Streeten, Elizabeth; März, Winfried; Fox, Caroline; Coresh, Josef; Wallaschofski, Henri; Pankow, James S; de Boer, Ian H; Kestenbaum, Bryan

    2017-05-01

    Parathyroid hormone (PTH) is a primary calcium regulatory hormone. Elevated serum PTH concentrations in primary and secondary hyperparathyroidism have been associated with bone disease, hypertension, and in some studies, cardiovascular mortality. Genetic causes of variation in circulating PTH concentrations are incompletely understood. We performed a genome-wide association study of serum PTH concentrations among 29,155 participants of European ancestry from 13 cohort studies ( n =22,653 and n =6502 in discovery and replication analyses, respectively). We evaluated the association of single nucleotide polymorphisms (SNPs) with natural log-transformed PTH concentration adjusted for age, sex, season, study site, and principal components of ancestry. We discovered associations of SNPs from five independent regions with serum PTH concentration, including the strongest association with rs6127099 upstream of CYP24A1 ( P =4.2 × 10 -53 ), a gene that encodes the primary catabolic enzyme for 1,25-dihydroxyvitamin D and 25-dihydroxyvitamin D. Each additional copy of the minor allele at this SNP associated with 7% higher serum PTH concentration. The other SNPs associated with serum PTH concentration included rs4074995 within RGS14 ( P =6.6 × 10 -17 ), rs219779 adjacent to CLDN14 ( P =3.5 × 10 -16 ), rs4443100 near RTDR1 ( P =8.7 × 10 -9 ), and rs73186030 near CASR ( P =4.8 × 10 -8 ). Of these five SNPs, rs6127099, rs4074995, and rs219779 replicated. Thus, common genetic variants located near genes involved in vitamin D metabolism and calcium and renal phosphate transport associated with differences in circulating PTH concentrations. Future studies could identify the causal variants at these loci, and the clinical and functional relevance of these variants should be pursued. Copyright © 2017 by the American Society of Nephrology.

  12. RVboost: RNA-seq variants prioritization using a boosting method.

    Science.gov (United States)

    Wang, Chen; Davila, Jaime I; Baheti, Saurabh; Bhagwate, Aditya V; Wang, Xue; Kocher, Jean-Pierre A; Slager, Susan L; Feldman, Andrew L; Novak, Anne J; Cerhan, James R; Thompson, E Aubrey; Asmann, Yan W

    2014-12-01

    RNA-seq has become the method of choice to quantify genes and exons, discover novel transcripts and detect fusion genes. However, reliable variant identification from RNA-seq data remains challenging because of the complexities of the transcriptome, the challenges of accurately mapping exon boundary spanning reads and the bias introduced during the sequencing library preparation. We developed RVboost, a novel method specific for RNA variant prioritization. RVboost uses several attributes unique in the process of RNA library preparation, sequencing and RNA-seq data analyses. It uses a boosting method to train a model of 'good quality' variants using common variants from HapMap, and prioritizes and calls the RNA variants based on the trained model. We packaged RVboost in a comprehensive workflow, which integrates tools of variant calling, annotation and filtering. RVboost consistently outperforms the variant quality score recalibration from the Genome Analysis Tool Kit and the RNA-seq variant-calling pipeline SNPiR in 12 RNA-seq samples using ground-truth variants from paired exome sequencing data. Several RNA-seq-specific attributes were identified as critical to differentiate true and false variants, including the distance of the variant positions to exon boundaries, and the percent of the reads supporting the variant in the first six base pairs. The latter identifies false variants introduced by the random hexamer priming during the library construction. The RVboost package is implemented to readily run in Mac or Linux environments. The software and user manual are available at http://bioinformaticstools.mayo.edu/research/rvboost/. © The Author 2014. Published by Oxford University Press.

  13. Carcinoma-risk variant of EBNA1 deregulates Epstein-Barr Virus episomal latency.

    Science.gov (United States)

    Dheekollu, Jayaraju; Malecka, Kimberly; Wiedmer, Andreas; Delecluse, Henri-Jacques; Chiang, Alan K S; Altieri, Dario C; Messick, Troy E; Lieberman, Paul M

    2017-01-31

    Epstein-Barr Virus (EBV) latent infection is a causative co-factor for endemic Nasopharyngeal Carcinoma (NPC). NPC-associated variants have been identified in EBV-encoded nuclear antigen EBNA1. Here, we solve the X-ray crystal structure of an NPC-derived EBNA1 DNA binding domain (DBD) and show that variant amino acids are found on the surface away from the DNA binding interface. We show that NPC-derived EBNA1 is compromised for DNA replication and episome maintenance functions. Recombinant virus containing the NPC EBNA1 DBD are impaired in their ability to immortalize primary B-lymphocytes and suppress lytic transcription during early stages of B-cell infection. We identify Survivin as a host protein deficiently bound by the NPC variant of EBNA1 and show that Survivin depletion compromises EBV episome maintenance in multiple cell types. We propose that endemic variants of EBNA1 play a significant role in EBV-driven carcinogenesis by altering key regulatory interactions that destabilize latent infection.

  14. Psoriasis Patients Are Enriched for Genetic Variants That Protect against HIV-1 Disease

    Science.gov (United States)

    Chen, Haoyan; Hayashi, Genki; Lai, Olivia Y.; Dilthey, Alexander; Kuebler, Peter J.; Wong, Tami V.; Martin, Maureen P.; Fernandez Vina, Marcelo A.; McVean, Gil; Wabl, Matthias; Leslie, Kieron S.; Maurer, Toby; Martin, Jeffrey N.; Deeks, Steven G.; Carrington, Mary; Bowcock, Anne M.; Nixon, Douglas F.; Liao, Wilson

    2012-01-01

    An important paradigm in evolutionary genetics is that of a delicate balance between genetic variants that favorably boost host control of infection but which may unfavorably increase susceptibility to autoimmune disease. Here, we investigated whether patients with psoriasis, a common immune-mediated disease of the skin, are enriched for genetic variants that limit the ability of HIV-1 virus to replicate after infection. We analyzed the HLA class I and class II alleles of 1,727 Caucasian psoriasis cases and 3,581 controls and found that psoriasis patients are significantly more likely than controls to have gene variants that are protective against HIV-1 disease. This includes several HLA class I alleles associated with HIV-1 control; amino acid residues at HLA-B positions 67, 70, and 97 that mediate HIV-1 peptide binding; and the deletion polymorphism rs67384697 associated with high surface expression of HLA-C. We also found that the compound genotype KIR3DS1 plus HLA-B Bw4-80I, which respectively encode a natural killer cell activating receptor and its putative ligand, significantly increased psoriasis susceptibility. This compound genotype has also been associated with delay of progression to AIDS. Together, our results suggest that genetic variants that contribute to anti-viral immunity may predispose to the development of psoriasis. PMID:22577363

  15. Performance comparison of various time variant filters

    Energy Technology Data Exchange (ETDEWEB)

    Kuwata, M. [JEOL Engineering Co. Ltd., Akishima, Tokyo (Japan); Husimi, K.

    1996-07-01

    This paper describes the advantage of the trapezoidal filter used in semiconductor detector system comparing with the other time variant filters. The trapezoidal filter is the compose of a rectangular pre-filter and a gated integrator. We indicate that the best performance is obtained by the differential-integral summing type rectangular pre-filter. This filter is not only superior in performance, but also has the useful feature that the rising edge of the output waveform is linear. We introduce an example of this feature used in a high-energy experiment. (author)

  16. Research progress of behavioral variant frontotemporal dementia

    Directory of Open Access Journals (Sweden)

    Xiao-hua GU

    2015-07-01

    Full Text Available There is no epidemiological data of frontotemporal dementia (FTD in China. The application of updated diagnostic criteria, publishing of frontotemporal lobar degeneration (FTLD consensus in China, development of multimodal imaging and biomarkers promote the clinical understanding on behavioral variant frontotemporal dementia (bvFTD. There is still no drugs treating FTD approved by U.S. Food and Drug Administration (FDA. Multidisciplinary intervention may delay the progression of bvFTD. DOI: 10.3969/j.issn.1672-6731.2015.07.006

  17. Genetic variants associated with lung function

    DEFF Research Database (Denmark)

    Thyagarajan, Bharat; Wojczynski, Mary; Minster, Ryan L

    2014-01-01

    ) associated with FEV1/FVC, none of which were replicated in the CHARGE/SpiroMeta consortia. Using linkage analysis, we identified a novel linkage peak in chromosome 2 at 219 cM for FEV1/FVC (LOD: 3.29) and confirmed a previously reported linkage peak in chromosome 6 at 28 cM (LOD: 3.33) for FEV1. CONCLUSION......: Future studies need to identify the rare genetic variants underlying the linkage peak in chromosome 6 for FEV1....

  18. Sex steroids and variants of gender identity.

    Science.gov (United States)

    Meyer-Bahlburg, Heino F L

    2013-09-01

    This article summarizes for the practicing endocrinologist the current literature on the psychobiology of the development of gender identity and its variants in individuals with disorders of sex development (DSD) or with non-DSD transgenderism. Gender reassignment remains the treatment of choice for strong and persistent gender dysphoria in both categories, but more research is needed on the short-term and long-term effects of puberty-suppressing medications and cross-sex hormones on brain and behavior. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Oral fibrolipoma: A rare histological variant

    Directory of Open Access Journals (Sweden)

    Treville Pereira

    2014-01-01

    Full Text Available Lipomas are benign soft tissue mesenchymal neoplasms. Fibrolipoma is a histological variant of lipoma that mostly affects the buccal mucosa and causes functional and cosmetic disabilities. The diagnosis and differentiation of fibrolipoma with clinically similar lesions such as fibroma and pleomorphic adenoma is very essential for a correct treatment plan and complete follow-up. This article presents a case of a 35-year-old female with a fibrolipoma on the lingual marginal gingiva of the mandibular left third molar.

  20. Block Copolymers: Synthesis and Applications in Nanotechnology

    Science.gov (United States)

    Lou, Qin

    This study is focused on the synthesis and study of (block) copolymers using reversible deactivation radical polymerizations (RDRPs), including atom transfer radical polymerization (ATRP) and reversible addition-fragmentation chain transfer (RAFT) polymerization. In particular, two primary areas of study are undertaken: (1) a proof-of-concept application of lithographic block copolymers, and (2) the mechanistic study of the deposition of titania into block copolymer templates for the production of well-ordered titania nanostructures. Block copolymers have the ability to undergo microphase separation, with an average size of each microphase ranging from tens to hundreds of nanometers. As such, block copolymers have been widely considered for nanotechnological applications over the past two decades. The development of materials for various nanotechnologies has become an increasingly studied area as improvements in many applications, such as those found in the semiconductor and photovoltaic industries are constantly being sought. Significant growth in developments of new synthetic methods ( i.e. RDRPs) has allowed the production of block copolymers with molecular (and sometimes atomic) definition. In turn, this has greatly expanded the use of block copolymers in nanotechnology. Herein, we describe the synthesis of statistical and block copolymers of 193 nm photolithography methacrylate and acrylate resist monomers with norbornyl and adamantyl moieties using RAFT polymerization.. For these resist (block) copolymers, the phase separation behaviors were examined by atomic force microscopy (AFM). End groups were removed from the polymers to avoid complications during the photolithography since RAFT end groups absorb visible light. Poly(glycidyl methacrylate-block-polystyrene) (PGMA-b-PS) was synthesize by ATRP and demonstrated that this block copolymer acts as both a lithographic UV (365 nm) photoresist and a self-assembly material. The PGMA segments can undergo cationic

  1. The mixed block/event-related design.

    Science.gov (United States)

    Petersen, Steven E; Dubis, Joseph W

    2012-08-15

    Neuroimaging studies began using block design and event-related design experiments. While providing many insights into brain functions, these fMRI design types ignore components of the BOLD signal that can teach us additional elements. The development of the mixed block/event-related fMRI design allowed for a fuller characterization of nonlinear and time-sensitive neuronal responses: for example, the interaction between block and event related factors and the simultaneous extraction of transient activity related to trials and block transitions and sustained activity related to task-level processing. This review traces the origins of the mixed block/event-related design from conceptual precursors to a seminal paper and on to subsequent studies using the method. The review also comments on aspects of the experimental design that must be considered when attempting to use the mixed block/event-related design. When taking into account these considerations, the mixed block/event-related design allows fuller utilization of the BOLD signal allowing deeper interpretation of how regions of the brain function on multiple timescales. Copyright © 2011 Elsevier Inc. All rights reserved.

  2. Development of Alkali Activated Geopolymer Masonry Blocks

    Science.gov (United States)

    Venugopal, K.; Radhakrishna; Sasalatti, Vinod

    2016-09-01

    Cement masonry units are not considered as sustainable since their production involves consumption of fuel, cement and natural resources and therefore it is essential to find alternatives. This paper reports on making of geopolymer solid & hollow blocks and masonry prisms using non conventional materials like fly ash, ground granulated blast furnace slag (GGBFS) and manufactured sand and curing at ambient temperature. They were tested for water absorption, initial rate of water absorption, dry density, dimensionality, compressive, flexural and bond-strength which were tested for bond strength with and without lateral confinement, modulus of elasticity, alternative drying & wetting and masonry efficiency. The properties of geopolymer blocks were found superior to traditional masonry blocks and the masonry efficiency was found to increase with decrease in thickness of cement mortar joints. There was marginal difference in strength between rendered and unrendered geopolymer masonry blocks. The percentage weight gain after 7 cycles was less than 6% and the percentage reduction in strength of geopolymer solid blocks and hollow blocks were 26% and 28% respectively. Since the properties of geopolymer blocks are comparatively better than the traditional masonry they can be strongly recommended for structural masonry.

  3. Transparent superhydrophobic coating application to the interlocking clay block for the microbial growth mitigation

    Science.gov (United States)

    Nimittrakoolchai, O.; Suwan, M.; Supothina, S.

    2017-12-01

    Interlocking clay block is of widespread use in many countries due to its less labor-intensive design. The block comprises of considerable amount of pore structures; therefore water can easily penetrate into it causing deterioration by natural weathering as well as the growth of microbes on its surface. In this present work, a transparent, superhydrophobic coating was applied onto the block’s surface to prevent water absorption. The coating which is a poly(methyl hydrogensiloxane) base containing fumed SiO2 nanoparticle was designed to possess surface topographic feature similar to that of the lotus leaf. After coating the block with the superhydrophobic compound, its water absorption decreased from 11.5 to 4.8% and porosity substantially decreased from 22.5 to 9.2%, while bulk and apparent densities did not change. Accelerated weathering test revealed that the coating had good stability. The coated samples exhibited growth inhibition of algae.

  4. A revisit of transthecal digital block and traditional digital block for anesthesia of the finger

    Directory of Open Access Journals (Sweden)

    Mohammad Dehghani

    2007-12-01

    Full Text Available BACKGROUND: Finger injuries are very common and the majority can be treated under digital block anesthesia. Traditional digital block is one of the most commonly performed blocks by care providers in several medical fields. There is another less known method, transthecal (Pulley block, in which local anesthesia is injected into the flexor tendon sheath.
    METHODS: A randomized clinical trial was performed to compare the transthecal (Pulley and traditional digital block with regard to the length of anesthesia and the need for another anesthetic method (due to insufficient anesthesia as a supplement. We divided 100 patients who needed digital block due to finger injury, into two groups randomly. In each group the patients were anesthetized either by traditional or transthecal digital block. All blocks were performed by the same investigator.
    RESULTS: Mean length of anesthesia was 34.2 minutes in the transthecal digital block method versus 33.8 minutes in the traditional digital block method (P>0.05. A repeated injection or local infiltration as a supplement was necessary only in 5 instances in the traditional digital block method (P<0.05.
    CONCLUSIONS: Regarding fewer injections and reduced amounts of lidocaine, absence of neurovascular bundles damage and comparable length of anesthesia and no need to supplemental anesthesia, transthecal digital block is an appropriate alternative to traditional digital block.
    KEY WORDS: Digital block, transthecal, pulley, finger, flexor tendon sheath.

  5. Exploring Energy Efficiency of Lightweight Block Ciphers

    DEFF Research Database (Denmark)

    Banik, Subhadeep; Bogdanov, Andrey; Regazzoni, Francesco

    2016-01-01

    is the encryption of one plaintext. By studying the energy consumption model of a CMOS gate, we arrive at the conclusion that the energy consumed per cycle during the encryption operation of an r-round unrolled architecture of any block cipher is a quadratic function in r. We then apply our model to 9 well known......In the last few years, the field of lightweight cryptography has seen an influx in the number of block ciphers and hash functions being proposed. One of the metrics that define a good lightweight design is the energy consumed per unit operation of the algorithm. For block ciphers, this operation...

  6. Evaluative Conditioning is Insensitive to Blocking

    Directory of Open Access Journals (Sweden)

    Tom Beckers

    2009-01-01

    Full Text Available Evaluative conditioning has been claimed to have a number of functional characteristics that set it apart from other forms of associative learning in humans, such as insensitivity to extinction and contingency, independence of contingency awareness, and insensitivity to modulation. Despite its potential theoretical importance, until now few data are available concerning the susceptibility of evaluative conditioning to cue competition effects such as blocking. In the present study, we assessed the susceptibility of acquired preferences and evaluations to blocking in a candy game. Results suggest that evaluative conditioning is not susceptible to blocking. We discuss this observation in the light of theoretical accounts of evaluative conditioning and associative learning in humans.

  7. Blocks and families for cyclotomic Hecke algebras

    CERN Document Server

    Chlouveraki, Maria

    2009-01-01

    The definition of Rouquier for the families of characters introduced by Lusztig for Weyl groups in terms of blocks of the Hecke algebras has made possible the generalization of this notion to the case of complex reflection groups. The aim of this book is to study the blocks and to determine the families of characters for all cyclotomic Hecke algebras associated to complex reflection groups. This volume offers a thorough study of symmetric algebras, covering topics such as block theory, representation theory and Clifford theory, and can also serve as an introduction to the Hecke algebras of complex reflection groups.

  8. Measurement of soil moisture using gypsum blocks

    DEFF Research Database (Denmark)

    Friis Dela, B.

    For the past 50 years, gypsum blocks have been used to determine soil moisture content. This report describes a method for calibrating gypsum blocks for soil moisture measurements. Moisture conditions inside a building are strongly influenced by the moisture conditions in the soil surrounding...... the building. Consequently, measuring the moisture of the surrounding soil is of great importance for detecting the source of moisture in a building. Up till now, information has been needed to carry out individual calibrations for the different types of gypsum blocks available on the market and to account...

  9. Parallel block inversion of geophysical data

    Science.gov (United States)

    Pereyra, Victor L.

    1993-12-01

    We present an automatic blocking algorithm for some medium size nonlinear least squares problems that arise in the inversion of travel time data in geophysics. This blocking leads to a nonlinear Gauss-Seidel type iteration which can be distributed to a network of computers. The low dimensional blocks are also amenable to global optimization methods which leads to further parallelization. All this is necessary because the original problem is generally non- convex, ill-conditioned, with a goal functional that is very expensive to evaluate.

  10. Productivity assessment of Angola's oil blocks

    International Nuclear Information System (INIS)

    Barros, Carlos Pestana; Managi, Shunsuke

    2009-01-01

    This paper analyzes the change in productivity as a result of Angola oil policy from 2001 to 2007. Angola oil blocks are the main source of tax receipts and, therefore, strategically important for public finances. A Malmquist index with the input technological bias is applied to measure productivity change. Oil blocks on average became both more efficient and experienced technological progress. Our results indicate that the traditional growth accounting method, which assumes Hicks neutral technological change, is not appropriate for analyzing changes in productivity for Angola oil blocks. Policy implications are derived. (author)

  11. Combining writing block treatments: theory and research.

    Science.gov (United States)

    Boice, R

    1992-03-01

    Four traditional formats of treatment for writing blocks (automaticity, regimen, self-control, and social skills training) proved insufficient to maintain unblocking in professorial writers for periods of an academic year. A combined application of the four historically prominent interventions was clearly more effective in terms of stable productivity, manuscripts finished and submitted, and manuscripts accepted for publication. Because writing blocks are too often conceptualized and treated by way of lore, a theory of blocking is proposed that clarifies the fundamental steps in effecting lasting unblocking.

  12. Theory of circuit block switch-off

    Directory of Open Access Journals (Sweden)

    S. Henzler

    2004-01-01

    Full Text Available Switching-off unused circuit blocks is a promising approach to supress static leakage currents in ultra deep sub-micron CMOS digital systems. Basic performance parameters of Circuit Block Switch-Off (CBSO schemes are defined and their dependence on basic circuit parameters is estimated. Therefore the design trade-off between strong leakage suppression in idle mode and adequate dynamic performance in active mode can be supported by simple analytic investigations. Additionally, a guideline for the estimation of the minimum time for which a block deactivation is useful is derived.

  13. Seismic proof test of shielding block walls

    International Nuclear Information System (INIS)

    Ohte, Yukio; Watanabe, Takahide; Watanabe, Hiroyuki; Maruyama, Kazuhide

    1989-01-01

    Most of the shielding block walls used for building nuclear facilities are built by dry process. When a nuclear facility is designed, seismic waves specific at each site are set as input seismic motions and they are adopted in the design. Therefore, it is necessary to assure safety of the shielding block walls for earthquake by performing anti-seismic experiments under the conditions at each site. In order to establish the normal form that can be applied to various seismic conditions in various areas, Shimizu Corp. made an actual-size test samples for the shielding block wall and confirmed the safety for earthquake and validity of normalization. (author)

  14. False discovery rates for rare variants from sequenced data.

    Science.gov (United States)

    Capanu, Marinela; Seshan, Venkatraman E

    2015-02-01

    The detection of rare deleterious variants is the preeminent current technical challenge in statistical genetics. Sorting the deleterious from neutral variants at a disease locus is challenging because of the sparseness of the evidence for each individual variant. Hierarchical modeling and Bayesian model uncertainty are two techniques that have been shown to be promising in pinpointing individual rare variants that may be driving the association. Interpreting the results from these techniques from the perspective of multiple testing is a challenge and the goal of this article is to better understand their false discovery properties. Using simulations, we conclude that accurate false discovery control cannot be achieved in this framework unless the magnitude of the variants' risk is large and the hierarchical characteristics have high accuracy in distinguishing deleterious from neutral variants. © 2014 WILEY PERIODICALS, INC.

  15. Functional materials derived from block copolymer self-assembly

    DEFF Research Database (Denmark)

    Li, Tao

    surface energy, including polymers, silicon and graphene, thus bypassing the laborious and delicate substrate chemical pre-modification. To push the boundary even further for minimal lithography steps, a scalable ultra-fast block copolymer lithography procedure is developed. Using selective solvent spin....... We believe this project opens up for a number of strategies aiming at the creation of high-performance functional materials on the length scale of sub-20 nanometers that cannot be manufactured in an easy fashion by conventional top-down lithography methods....

  16. Elliptic genus derivation of 4d holomorphic blocks

    Science.gov (United States)

    Poggi, Matteo

    2018-03-01

    We study elliptic vortices on ℂ × T 2 by considering the 2d quiver gauge theory describing their moduli spaces. The elliptic genus of these moduli spaces is the elliptic version of vortex partition function of the 4d theory. We focus on two examples: the first is a N = 1, U( N ) gauge theory with fundamental and anti-fundamental matter; the second is a N = 2, U( N ) gauge theory with matter in the fundamental representation. The results are instances of 4d "holomorphic blocks" into which partition functions on more complicated surfaces factorize. They can also be interpreted as free-field representations of elliptic Virasoro algebrae.

  17. Spatial distribution of ice blocks on Enceladus and implications for their origin and emplacement

    Science.gov (United States)

    Martens, Hilary R.; Ingersoll, Andrew P.; Ewald, Shawn P.; Helfenstein, Paul; Giese, Bernd

    2015-01-01

    and condensation around surface vents, however, cannot be ruled out. Further, sublimation processes likely erode and disaggregate ice blocks from solid exposures of ice, especially near the warm tiger-stripe fractures. The relative paucity of blocks beyond the bounds of the SPT, particularly on stratigraphically old cratered terrains, may be explained in part by mantling of the surface by fine particulate ice grains that accumulate over time.

  18. Brachial Plexus Anatomy: Normal and Variant

    Directory of Open Access Journals (Sweden)

    Steven L. Orebaugh

    2009-01-01

    Full Text Available Effective brachial plexus blockade requires a thorough understanding of the anatomy of the plexus, as well as an appreciation of anatomic variations that may occur. This review summarizes relevant anatomy of the plexus, along with variations and anomalies that may affect nerve blocks conducted at these levels. The Medline, Cochrane Library, and PubMed electronic databases were searched in order to compile reports related to the anatomy of the brachial plexus using the following free terms: "brachial plexus", "median nerve", "ulnar nerve", "radial nerve", "axillary nerve", and "musculocutanous nerve". Each of these was then paired with the MESH terms "anatomy", "nerve block", "anomaly", "variation", and "ultrasound". Resulting articles were hand searched for additional relevant literature. A total of 68 searches were conducted, with a total of 377 possible articles for inclusion. Of these, 57 were found to provide substantive information for this review. The normal anatomy of the brachial plexus is briefly reviewed, with an emphasis on those features revealed by use of imaging technologies. Anomalies of the anatomy that might affect the conduct of the various brachial plexus blocks are noted. Brachial plexus blockade has been effectively utilized as a component of anesthesia for upper extremity surgery for a century. Over that period, our understanding of anatomy and its variations has improved significantly. The ability to explore anatomy at the bedside, with real-time ultrasonography, has improved our appreciation of brachial plexus anatomy as well.

  19. Signal-Conditioning Block of a 1 × 200 CMOS Detector Array for a Terahertz Real-Time Imaging System

    Directory of Open Access Journals (Sweden)

    Jong-Ryul Yang

    2016-03-01

    Full Text Available A signal conditioning block of a 1 × 200 Complementary Metal-Oxide-Semiconductor (CMOS detector array is proposed to be employed with a real-time 0.2 THz imaging system for inspecting large areas. The plasmonic CMOS detector array whose pixel size including an integrated antenna is comparable to the wavelength of the THz wave for the imaging system, inevitably carries wide pixel-to-pixel variation. To make the variant outputs from the array uniform, the proposed signal conditioning block calibrates the responsivity of each pixel by controlling the gate bias of each detector and the voltage gain of the lock-in amplifiers in the block. The gate bias of each detector is modulated to 1 MHz to improve the signal-to-noise ratio of the imaging system via the electrical modulation by the conditioning block. In addition, direct current (DC offsets of the detectors in the array are cancelled by initializing the output voltage level from the block. Real-time imaging using the proposed signal conditioning block is demonstrated by obtaining images at the rate of 19.2 frame-per-sec of an object moving on the conveyor belt with a scan width of 20 cm and a scan speed of 25 cm/s.

  20. Signal-Conditioning Block of a 1 × 200 CMOS Detector Array for a Terahertz Real-Time Imaging System.

    Science.gov (United States)

    Yang, Jong-Ryul; Lee, Woo-Jae; Han, Seong-Tae

    2016-03-02

    A signal conditioning block of a 1 × 200 Complementary Metal-Oxide-Semiconductor (CMOS) detector array is proposed to be employed with a real-time 0.2 THz imaging system for inspecting large areas. The plasmonic CMOS detector array whose pixel size including an integrated antenna is comparable to the wavelength of the THz wave for the imaging system, inevitably carries wide pixel-to-pixel variation. To make the variant outputs from the array uniform, the proposed signal conditioning block calibrates the responsivity of each pixel by controlling the gate bias of each detector and the voltage gain of the lock-in amplifiers in the block. The gate bias of each detector is modulated to 1 MHz to improve the signal-to-noise ratio of the imaging system via the electrical modulation by the conditioning block. In addition, direct current (DC) offsets of the detectors in the array are cancelled by initializing the output voltage level from the block. Real-time imaging using the proposed signal conditioning block is demonstrated by obtaining images at the rate of 19.2 frame-per-sec of an object moving on the conveyor belt with a scan width of 20 cm and a scan speed of 25 cm/s.