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Sample records for transverse tubular membrane

  1. Effects of beta-escin and saponin on the transverse-tubular system and sarcoplasmic reticulum membranes of rat and toad skeletal muscle.

    Science.gov (United States)

    Launikonis, B S; Stephenson, D G

    1999-05-01

    Mechanically skinned skeletal muscle fibres from rat and toad were exposed to the permeabilizing agents beta-escin and saponin. The effects of these agents on the sealed transverse tubular system (t-system) and sarcoplasmic reticulum (SR) were examined by looking at changes in the magnitude of the force responses to t-system depolarization, the time course of the fluorescence of fura-2 trapped in the sealed t-system, and changes in the magnitude of caffeine-induced contractures following SR loading with Ca2+ under defined conditions. In the presence of 2 microg ml-1 beta-escin and saponin, the response to t-system depolarization was not completely abolished, decreasing to a plateau, and a large proportion of fura-2 remained in the sealed t-system. At 10 microg ml-1, both agents abolished the ability of both rat and toad preparations to respond to t-system depolarization after 3 min of exposure, but a significant amount of fura-2 remained in sealed t-tubules even after exposure to 100 microg ml-1 beta-escin and saponin for 10 min. beta-Escin took longer than saponin to reduce the t-system depolarizations and fura-2 content of the sealed t-system to a similar level. The ability of the SR to load Ca2+ was reduced to a lower level after treatment with beta-escin than saponin. This direct effect on the SR occurred at much lower concentrations for rat (2 microg ml-1 beta-escin and 10 microg ml-1 saponin) than toad (10 microg ml-1 beta-escin and 150 microg ml-1 saponin). The reverse order in sensitivities to beta-escin and saponin of t-system and SR membranes indicates that the mechanisms of action of beta-escin and saponin are different in the two types of membrane. In conclusion, this study shows that: (1) beta-escin has a milder action on the surface membrane than saponin; (2) beta-escin is a more potent modifier of SR function; (3) simple permeabilization of membranes is not sufficient to explain the effects of beta-escin and saponin on muscle membranes; and (4) the t

  2. Modelling the cardiac transverse-axial tubular system

    Czech Academy of Sciences Publication Activity Database

    Pásek, Michal; Šimurda, J.; Christé, G.; Orchard, C.

    2008-01-01

    Roč. 96, - (2008), s. 226-246 ISSN 0079-6107 Institutional research plan: CEZ:AV0Z20760514 Keywords : cardiac cell * transverse-axial tubular system * quantitative modelling Subject RIV: BO - Biophysics Impact factor: 6.388, year: 2008

  3. Tubular membrane bioreactors for biotechnological processes.

    Science.gov (United States)

    Wolff, Christoph; Beutel, Sascha; Scheper, Thomas

    2013-02-01

    This article is an overview of bioreactors using tubular membranes such as hollow fibers or ceramic capillaries for cultivation processes. This diverse group of bioreactor is described here in regard to the membrane materials used, operational modes, and configurations. The typical advantages of this kind of system such as environments with low shear stress together with high cell densities and also disadvantages like poor oxygen supply are summed up. As the usage of tubular membrane bioreactors is not restricted to a certain organism, a brief overview of various applications covering nearly all types of cells from prokaryotic to eukaryotic cells is also given here.

  4. Tubular Steel Arch Stabilized by Textile Membranes

    Directory of Open Access Journals (Sweden)

    Ondrej Svoboda

    2016-10-01

    Full Text Available Tubular steel arch supporting textile membrane roofing is investigated experimentally and numerically. The stabilization effects of the textile membrane on in-plane and out-of-plane behavior of the arch is of primary interest. First a model of a large membrane structure tested in laboratory is described. Prestressed membranes of PVC coated polyester fabric Ferrari® Précontraint 702S were used as a currently standard and excellent material. The test arrangement, loading and resulting load/deflection values are presented. The supporting structure consisted of two steel arch tubes, outer at edge of the membrane and inner supporting interior of the membrane roofing. The stability and strength behavior of the inner tube under both symmetrical and asymmetrical loading was monitored and is shown in some details. Second the SOFiSTiK software was employed to analyze the structural behavior in 3D, using geometrically nonlinear analysis with imperfections (GNIA. The numerical analysis, FE mesh sensitivity, the membrane prestressing and common boundary conditions are validated by test results. Finally a parametrical study concerning stability of mid arch with various geometries in a membrane structure with several supporting arches is presented, with recommendations for a practical design.

  5. Mechanical reliability of geometrically imperfect tubular oxygen transport membranes

    DEFF Research Database (Denmark)

    Kwok, Kawai; Frandsen, Henrik Lund; Søgaard, Martin

    2014-01-01

    operation. This paper investigates numerically the failure risk of tubular oxygen transport membranes under industrial operating conditions using finite element modeling and Weibull strength analysis. The effects of component manufacturing defects on fracture probability are elucidated by explicit modeling...... of imperfections in the tubular membrane geometry. A supported membrane made of dense and porous Zr-doped-BSCF is studied as an illustrative example. It is shown that stresses induced by oxygen stoichiometry gradients relax over time due to creep and external pressure is the dominating source of stress in the long...... quality (in terms of specification of tolerable deviation from perfect tubular shape) that allows fail-safe operation are deduced....

  6. Equilibrium shapes of tubular lipid membranes.

    Science.gov (United States)

    Jelerčič, Urška

    2017-04-19

    Tubular vesicles represent abundant structural motifs which are observed both in experiments and in nature. We analyse them within the theory of bending elasticity and determine the equilibrium solutions at fixed volume, surface area, and segment length without imposing any specific symmetry or periodicity. We identify four different non-periodic equilibrium shapes. Depending on the precise value of the constraints or the corresponding Lagrange multipliers, these four shapes include: (i) snake-like and (ii) helical structures, (iii) tubes with a spherical body, and (iv) tubes with a discoidal body. However different in the details, all of the shapes have the same general cylindrical morphology which is either globally modulated or is a superposition of an additional structural motif and the cylinder. These results point to a great significance of the circular cylindrical shape and offer a comprehensive and general analysis of the shape of tubular vesicles.

  7. Experimental extrusion of tubular multilayer materials for Oxygen Transport Membranes

    DEFF Research Database (Denmark)

    Kothanda Ramachandran, Dhavanesan

    membrane based on gadolinia doped ceria oxide, (Ce0.9Gd0.1O1.95−δ), (CGO) was developed on a tubular, porous support structure based on cost-efficient magnesium oxide (MgO). The porous support structure was prepared by thermoplastic extrusion using MgO powder, thermoplastic binders and graphite pore former....... The results revealed sufficiently high bending strength values of 60 MPa for the MgO support at an operation temperature of 850 °C, whereas the strength at room temperature was 77 MPa. The oxygen permeation flux on an asymmetric tubular CGO membrane, consisting of an MgO support (porous), catalytic layer...

  8. The influence of transverse tubular delays on the kinetics of charge movement in mammalian skeletal muscle

    OpenAIRE

    1985-01-01

    A model was developed to describe the kinetics of slow, voltage- dependent charge movement in the rat omohyoid muscle. To represent the electrically distributed nature of the transverse tubular system (t- system), we followed an approach similar to that described by Adrian and Peachey (1973 J. Physiol. [Lond.]. 235:103), and approximated the fiber with 12 concentric cylindrical shells. Incorporated into each shell were capacitative and conductive elements that represented the passive electric...

  9. Tubular phase of self-avoiding anisotropic crystalline membranes

    International Nuclear Information System (INIS)

    Bowick, M.; Travesset, A.

    1999-01-01

    We analyze the tubular phase of self-avoiding anisotropic crystalline membranes. A careful analysis using renormalization group arguments together with symmetry requirements motivates the simplest form of the large-distance free energy describing fluctuations of tubular configurations. The non-self-avoiding limit of the model is shown to be exactly solvable. For the full self-avoiding model we compute the critical exponents using an var-epsilon expansion about the upper critical embedding dimension for general internal dimension D and embedding dimension d. We then exhibit various methods for reliably extrapolating to the physical point (D=2,d=3). Our most accurate estimates are ν=0.62 for the Flory exponent and ζ=0.80 for the roughness exponent. copyright 1999 The American Physical Society

  10. The influence of transverse tubular delays on the kinetics of charge movement in mammalian skeletal muscle.

    Science.gov (United States)

    Simon, B J; Beam, K G

    1985-01-01

    A model was developed to describe the kinetics of slow, voltage-dependent charge movement in the rat omohyoid muscle. To represent the electrically distributed nature of the transverse tubular system (t-system), we followed an approach similar to that described by Adrian and Peachey (1973 J. Physiol. [Lond.]. 235:103), and approximated the fiber with 12 concentric cylindrical shells. Incorporated into each shell were capacitative and conductive elements that represented the passive electrical properties of the t-system, and an element representing the mobile charge. The charge was assumed to obey a two-state scheme, in which the redistribution of charge is governed by a first-order reaction, and the rate constants linking the two states were assumed to depend on potential according to the constant field expression. The predictions of this "distributed two-state model" were compared with charge movements experimentally measured in individual fibers. For this comparison, first, the passive electrical parameters of the model were adjusted to fit the experimental linear capacity transient. Next, the Boltzmann expression was fitted to the steady state Q vs. V data of the fiber, thereby constraining the voltage dependence of the rate constants, but not their absolute magnitude. The absolute magnitude was determined by fitting the theory to an experimental charge movement at a single test potential, which in turn constrained the fits at all other test potentials. The distributed two-state model well described the rising and falling phases of ON, OFF, and stepped OFF charge movements at temperatures ranging from 3 to 25 degrees C. We thus conclude that tubular delays are sufficient to account for the rounded rising phase of experimental charge movements, and that it is unnecessary to postulate higher-order reaction schemes for the underlying charge redistribution.

  11. Mathematical modeling of methyl ester concentration distribution in a continuous membrane tubular reactor and comparison with conventional tubular reactor

    Science.gov (United States)

    Talaghat, M. R.; Jokar, S. M.; Modarres, E.

    2017-10-01

    The reduction of fossil fuel resources and environmental issues made researchers find alternative fuels include biodiesels. One of the most widely used methods for production of biodiesel on a commercial scale is transesterification method. In this work, the biodiesel production by a transesterification method was modeled. Sodium hydroxide was considered as a catalyst to produce biodiesel from canola oil and methanol in a continuous tubular ceramic membranes reactor. As the Biodiesel production reaction from triglycerides is an equilibrium reaction, the reaction rate constants depend on temperature and related linearly to catalyst concentration. By using the mass balance for a membrane tubular reactor and considering the variation of raw materials and products concentration with time, the set of governing equations were solved by numerical methods. The results clearly show the superiority of membrane reactor than conventional tubular reactors. Afterward, the influences of molar ratio of alcohol to oil, weight percentage of the catalyst, and residence time on the performance of biodiesel production reactor were investigated.

  12. Flux recovery of ceramic tubular membranes fouled with whey proteins: Some aspects of membrane cleaning

    Directory of Open Access Journals (Sweden)

    Popović Svetlana S.

    2008-01-01

    Full Text Available Efficiency of membrane processes is greatly affected by the flux reduction due to the deposits formation at the surface and/or in the pores of the membrane. Efficiency of membrane processes is affected by cleaning procedure applied to regenerate flux. In this work, flux recovery of ceramic tubular membranes with 50 and 200 nm pore size was investigated. The membranes were fouled with reconstituted whey solution for 1 hour. After that, the membranes were rinsed with clean water and then cleaned with sodium hydroxide solutions or formulated detergents (combination of P3 Ultrasil 67 and P3 Ultrasil 69. Flux recovery after the rinsing step was not satisfactory although fouling resistance reduction was significant so that chemical cleaning was necessary. In the case of 50 nm membrane total flux recovery was achieved after cleaning with 1.0% (w/w sodium hydroxide solution. In the case of 200 nm membrane total flux recovery was not achieved irrespective of the cleaning agent choice and concentration. Cleaning with commercial detergent was less efficient than cleaning with the sodium hydroxide solution.

  13. Copper recovery in a bench-scale carrier facilitated tubular supported liquid membrane system

    Directory of Open Access Journals (Sweden)

    Makaka S.

    2010-01-01

    Full Text Available The extraction of copper ions in a tubular supported liquid membrane using LIX 984NC as a mobile carrier was studied, evaluating the effect of the feed characteristics (flowrate, density, viscosity on the feedside laminar layer of the membrane. A vertical countercurrent, double pipe perspex benchscale reactor consisting of a single hydrophobic PVDF tubular membrane mounted inside was used in all test work. The membrane was impregnated with LIX 984NC and became the support for this organic transport medium. Dilute Copper solution passed through the centre pipe and sulphuric acid as strippant passed through the shell side. Copper was successfully transported from the feedside to the stripside and from the data obtained, a relationship between Schmidt, Reynolds and Sherwood number was achieved of.

  14. Gas-permeable hydrophobic tubular membranes for ammonia recovery in bio-electrochemical systems

    NARCIS (Netherlands)

    Kuntke, P.; Zamora, P.; Saakes, M.; Buisman, C.J.N.; Hamelers, H.V.M.

    2016-01-01

    The application of a gas-permeable hydrophobic tubular membrane in bio-electrochemical systems enables efficient recovery of ammonia (NH3) from their cathode compartments. Due to a hydrogen evolution reaction at the cathode, no chemical addition was required to increase the pH for

  15. Macrophage Chemotaxis in Anti-tubular Basement Membrane-Induced Interstitial Nephritis in Guinea Pigs

    NARCIS (Netherlands)

    Kennedy, Thomas L.; Merrow, Martha; Phillips, S. Michael; Norman, Michael; Neilson, Eric G.

    1985-01-01

    Interstitial renal lesions containing T cells and macrophages develop after 14 days in guinea pigs immunized to produce anti-tubular basement membrane-induced interstitial nephritis. We serially examined the renal venous and systemic arterial sera from such animals to determine if chemotactic

  16. A quantitative model of the cardiac ventricular cell incorporating the transverse-axial tubular system

    Czech Academy of Sciences Publication Activity Database

    Pásek, Michal; Christé, G.; Šimurda, J.

    2003-01-01

    Roč. 22, č. 3 (2003), s. 355-368 ISSN 0231-5882 R&D Projects: GA ČR GP204/02/D129 Institutional research plan: CEZ:AV0Z2076919 Keywords : cardiac cell * tubular system * quantitative modelling Subject RIV: BO - Biophysics Impact factor: 0.794, year: 2003

  17. Analysis of mass transfer characteristics in a tubular membrane using CFD modeling.

    Science.gov (United States)

    Yang, Jixiang; Vedantam, Sreepriya; Spanjers, Henri; Nopens, Ingmar; van Lier, Jules B

    2012-10-01

    In contrast to the large amount of research into aerobic membrane bioreactors, little work has been reported on anaerobic membrane bioreactors (AMBRs). As to the application of membrane bioreactors, membrane fouling is a key issue. Membrane fouling generally occurs more seriously in AMBRs than in aerobic membrane bioreactors. However, membrane fouling could be managed through the application of suitable shear stress that can be introduced by the application of a two-phase flow. When the two-phase flow is applied in AMBRs, little is known about the mass transfer characteristics, which is of particular importance, in tubular membranes of AMBRs. In our present work, we have employed fluid dynamic modeling to analyze the mass transfer characteristics in the tubular membrane of a side stream AMBR in which, gas-lift two-phase flow was applied. The modeling indicated that the mass transfer capacity at the membrane surface at the noses of gas bubbles was higher than the mass transfer capacity at the tails of the bubbles, which is in contrast to the results when water instead of sludge is applied. At the given mass transfer rate, the filterability of the sludge was found to have a strong influence on the transmembrane pressure at a steady flux. In addition, the model also showed that the shear stress in the internal space of the tubular membrane was mainly around 20 Pa but could be as high as about 40 Pa due to gas bubble movements. Nonetheless, at these shear stresses a stable particle size distribution was found for sludge particles. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Distribution of IGF receptors in the plasma membrane of proximal tubular cells

    International Nuclear Information System (INIS)

    Hammerman, M.R.; Rogers, S.

    1987-01-01

    To characterize the distribution of receptors for insulin-like growth factors I and II (IGF I and II) in the plasma membrane of the renal proximal tubular cell, the authors measured binding of 125 I-labeled IGF I and 125 I-labeled IGF II to proximal tubular basolateral and brush-border membranes and characterized IGF I-stimulated phosphorylation of detergent-solubilized membranes. 125 I-IGF bound primarily to a 135,000 relative molecular weight (M r ) protein and IGF II to a 260,000 M r protein in isolated membranes. Binding of 125 I-IGF I was severalfold greater in basolateral than in brush-border membranes. IGF I-stimulated phosphorylation of the 92,000 M r β-subunit of its receptors could be demonstrated only in basolateral membranes. These findings are consistent with an asymmetrical distribution of receptors for IGF I in the plasma membrane of the renal proximal tubular cell, localization being primary on the basolateral side. In contrast, binding of 125 I-IGF II to isolated basolateral and brush-border membranes was equivalent, suggesting that receptors for this peptide are distributed more symmetrically in the plasma membrane. The findings suggest that the action of IGF I in proximal tubule are mediated via interaction of circulating peptide with specific receptors in the basolateral membrane. However, the findings established the potential for actions of IGF II to be exerted in proximal tubule via interaction with both basolateral and/or brush-border membrane receptors

  19. PROCESSING AND CHARACTERIZATION OF TUBULAR CERAMIC SUPPORT FOR MICROFILTRATION MEMBRANE PREPARED FROM PYROPHYLLITE CLAY

    Directory of Open Access Journals (Sweden)

    Abedallah Talidi

    2011-09-01

    Full Text Available Tubular macroporous support for ceramic microfiltration membranes were prepared by extrusion followed by sintering of the low cost pyrophyllite clay. Clay powders mixed with some organic additives can be extruded to form a porous tubular support. The average pore size of the membrane is observed to increase from 5 µm to 10.8 µm when sintering temperature increase from 900 °C to 1200 °C. However, with the increase in temperature from 900 °C to 1200 °C, the support porosity is reduced from 47% to 30% and flexural strength is increased from 4 MPa to 17 MPa. The fabricated macro-porous supports are expected to have potential applications in the pre-treatment and also can be used like support for membranes of ultra-filtration.

  20. FBAR syndapin 1 recognizes and stabilizes highly curved tubular membranes in a concentration dependent manner

    DEFF Research Database (Denmark)

    Ramesh, Pradeep; Baroji, Younes F.; Seyyed Reihani, Seyyed Nader

    2013-01-01

    brain lipid vesicles and show that it senses membrane curvature at low density whereas it induces and reinforces tube stiffness at higher density. FBAR strongly up-concentrates on the high curvature tubes pulled out of Giant Unilamellar lipid Vesicles (GUVs), this sorting behavior is strongly amplified...... at low protein densities. Interestingly, FBAR from syndapin 1 has a large affinity for tubular membranes with curvatures larger than its own intrinsic concave curvature. Finally, we studied the effect of FBAR on membrane relaxation kinetics with high temporal resolution and found that the protein...... increases relaxation time of the tube holding force in a density-dependent fashion....

  1. Stress analysis and fail-safe design of bilayered tubular supported ceramic membranes

    DEFF Research Database (Denmark)

    Kwok, Kawai; Frandsen, Henrik Lund; Søgaard, Martin

    2014-01-01

    Supported ceramic membranes based on mixed ionic and electronic conductors are a promising technology for oxygen separation applications. In addition to chemically induced stress under oxygen activity gradients in the materials, strain mismatch between membrane and support gives rise...... to considerable stress that may compromise mechanical reliability. This paper presents an analysis of stress generated in tubular supported membranes during operation. Closed-form analytical solutions for stresses due to external pressures, strain gradients, and mismatch in materials properties are derived....... Stress distributions in two membrane systems have been analyzed and routes to minimize stress are proposed. For a Ba0.5Sr0.5Co0.8Fe0.2O3−δBa0.5Sr0.5Co0.8Fe0.2O3−δ membrane supported on a porous substrate of the same material under pressure-vacuum operation, the optimal configuration in terms...

  2. Voltage-dependent activation in purified reconstituted sodium channels from rabbit T-tubular membranes

    Energy Technology Data Exchange (ETDEWEB)

    Furman, R.E.; Tanaka, J.C.; Mueller, P.; Barchi, R.L.

    1986-01-01

    The authors have examined the voltage-dependent gating of batrachotoxin-modified sodium channels purified from rabbit T-tubular membranes in two ways. First, purified channels were reconstituted into planar bilayers and single-channel properties were measured. Batrachotoxin-activated channels showed steep voltage-dependent activation with half-maximal opening probabilities at potentials between -95 and -116 mV. The single-channel conductance averaged 20 pS and was independent of membrane potential. A second approach was used to establish that this voltage dependence was a characteristic of the entire population of purified channels and not just those few channels observed in planar bilayers. Channels reconstituted into egg phosphophatidyl-choline vesicles were functionally oriented by inclusion of internal saxitoxin; vesicle membrane potentials were then generated by K/sup +/ gradients in the presence of valinomycin. All of the specific /sup 22/Na/sup +/ influx activated by batrachotoxin and blocked by saxitoxin was found to be voltage sensitive, activating between predicted membrane potentials of -100 and -50 mV. The single-channel properties of the purified T-tubular sodium channel correspond closely to those seen with native sodium channels from rat sarcolemma. The voltage-dependent activation of the bactrachotoxin-modified reconstituted channel is the same as that seen with native channels in situ or in bilayers after exposure this toxin.

  3. Growth hormone activates phospholipase C in proximal tubular basolateral membranes from canine kidney

    International Nuclear Information System (INIS)

    Rogers, S.A.; Hammerman, M.R.

    1989-01-01

    To delineate pathways for signal transduction by growth hormone (GH) in proximal tubule, the authors incubated basolateral membranes isolated from canine kidney with human growth hormone (hGH) or human prolactin (hPrl) and measured levels of inositol trisphosphate (InsP 3 ) in suspensions and of diacylglycerol extractable from the membranes. Incubation with hGH, but not hPrl, increased levels of InsP 3 and diacylglycerol in a concentration-dependent manner. Half-maximal effects occurred between 0.1 and 1 nM hGH. Increased levels of InsP 3 were measured after as little as 5 sec of incubation with 1 nM hGH, and increase was maximal after 15 sec. Increases were no longer detectable after 60 sec because of dephosphorylation of InsP 3 in membrane suspensions. hGH did not affect rates of dephosphorylation. hGH-stimulated increases in InsP 3 were detectable in membranes suspended in 0, 0.1, and 0.2 μM calcium but not in 0.3 or 1.0 μM calcium. 125 I-labeled hGH-receptor complexes with M r values of 66,000 and 140,000 were identified in isolated basolateral membranes. The findings establish that GH activates phospholipase C in isolated canine renal proximal tubular basolateral membranes, potentially after binding to a specific receptor. This process could mediate signal transmission by GH across the plasma membrane of the proximal tubular cell and elsewhere

  4. Performance Analysis and Modeling of a Tubular Staggered-Tooth Transverse-Flux PM Linear Machine

    Directory of Open Access Journals (Sweden)

    Shaohong Zhu

    2016-03-01

    Full Text Available This paper investigates the performance analysis and mathematical modeling of a staggered-tooth transverse-flux permanent magnet linear synchronous machine (STTF-PMLSM, which is characterized by simple structure and low flux leakage. Firstly, the structure advantages and operation principle of the STTF-PMLSM are introduced, and a simplified one phase model is established to investigate the performance of the machine in order to save the computation time. Then, the electromagnetic characteristics, including no-load flux linkage, electromotive force (EMF, inductance, detent force and thrust force, are simulated and analyzed in detail. After that, the theoretical analysis of the detent force, thrust force, and power factor are carried out. And the theoretical analysis results are validated with 3-D finite-element method (FEM. Finally, an improved mathematical model of the machine based on d-q rotating coordinate system is proposed, in which inductance harmonics and coupling between d- and q-axis inductance is considered. The results from the proposed mathematical model are in accordance with the results from 3-D FEM, which proves the validity and effectiveness of the proposed mathematical model. This provides a powerful foundation for the control of the machine.

  5. Remodeling of the transverse tubular system after myocardial infarction in rabbit correlates with local fibrosis: A potential role of biomechanics.

    Science.gov (United States)

    Seidel, T; Sankarankutty, A C; Sachse, F B

    2017-11-01

    The transverse tubular system (t-system) of ventricular cardiomyocytes is essential for efficient excitation-contraction coupling. In cardiac diseases, such as heart failure, remodeling of the t-system contributes to reduced cardiac contractility. However, mechanisms of t-system remodeling are incompletely understood. Prior studies suggested an association with altered cardiac biomechanics and gene expression in disease. Since fibrosis may alter tissue biomechanics, we investigated the local microscopic association of t-system remodeling with fibrosis in a rabbit model of myocardial infarction (MI). Biopsies were taken from the MI border zone of 6 infarcted hearts and from 6 control hearts. Using confocal microscopy and automated image analysis, we quantified t-system integrity (I TT ) and the local fraction of extracellular matrix (f ECM ). In control, f ECM was 18 ± 0.3%. I TT was high and homogeneous (0.07 ± 0.006), and did not correlate with f ECM (R 2  = 0.05 ± 0.02). The MI border zone exhibited increased f ECM within 3 mm from the infarct scar (30 ± 3.5%, p system remodeling, with dilated, sheet-like components, resulting in low I TT (0.03 ± 0.008, p system remodeling decreased with infarct distance, I TT correlated better with decreasing f ECM (R 2  = 0.44) than with infarct distance (R 2  = 0.24, p system remodeling in the rabbit MI border zone resembles a phenotype previously described in human heart failure. T-system remodeling correlated with the amount of local fibrosis, which is known to stiffen cardiac tissue, but was not found in regions without fibrosis. Thus, locally altered tissue mechanics may contribute to t-system remodeling. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Severe neonatal complication of transverse lie after preterm premature rupture of membranes

    NARCIS (Netherlands)

    D.C.M. van der Kaay (Danielle); S. Horsch (S.); J.J. Duvekot (Hans)

    2013-01-01

    textabstractBoth transverse lie and preterm premature rupture of membranes (PPROM) are associated with neonatal morbidity and mortality. We present a neonate born at 29 weeks gestation with severe birth trauma after PPROM and transverse lie. The patient had extensive swelling and areas of

  7. Assessment of Mass Transfer Coefficients in Coalescing Slug Flow in Vertical Pipes and Applications to Tubular Airlift Membrane Bioreactors

    DEFF Research Database (Denmark)

    Ratkovich, Nicolas Rios; Berube, P.R.; Nopens, I.

    2011-01-01

    One of the operational challenges associated with membrane bioreactors (MBRs) is the fouling of the membranes. In tubular side-stream MBRs, fouling reduction can be achieved through controlling the hydrodynamics of the two-phase slug flow near the membrane surface. The two-phase slug flow induces......) cannot be applied directly. As an alternative, in this work, a multidisciplinary approach was selected, by exploiting dimensionless analysis using the Sherwood number. Mass transfer coefficients were measured at various superficial velocities of gas and liquid flow in a tubular system. Due...... to the variability of the mass transfer coefficient obtained for each experimental condition, the results were compiled into, mass transfer coefficient histograms (MTH) for analysis. A bimodal MTH was observed, with one peak corresponding to the mass transfer induced by the liquid flow, and the other peak induced...

  8. Experimental Study on the Fire Performance of Tubular Steel Columns with Membrane Protections for Prefabricated and Modular Steel Construction

    Directory of Open Access Journals (Sweden)

    Xin Zhang

    2018-03-01

    Full Text Available Experimental research was conducted to study the fire resistance of steel tubular columns used in prefabricated and modular construction. In order to achieve high-efficient prefabrication and fast on-site installation, membrane protections using board products and thermal insulation blankets are adopted as the favorable protection method. Three protected tubular columns were tested in a full-scale column furnace with axial load applied. The study variables were different membranes, including fiber reinforced calcium silicate (FRCS boards, rock wool and aluminum silica (Fiberfrax insulations. The results suggest that one layer of 12 mm FRCS board with rock wool insulation has insufficient fire protection. However, steel columns protected with two layers of 12 mm FRCS boards with insulation appeared to have good fire resistances and could achieve a fire resistance rating as high as 2.5~3.0 h.

  9. Severe neonatal complication of transverse lie after preterm premature rupture of membranes

    Science.gov (United States)

    Van der Kaay, D C M; Horsch, S; Duvekot, J J

    2013-01-01

    Both transverse lie and preterm premature rupture of membranes (PPROM) are associated with neonatal morbidity and mortality. We present a neonate born at 29 weeks gestation with severe birth trauma after PPROM and transverse lie. The patient had extensive swelling and areas of desquamated and necrotic skin of the right lower limb. Neonatal compartment syndrome (NCS) was suspected. Perfusion of the limb improved after decompressing subcutaneous incisions. A fetus in transverse lie may be mechanically damaged in the case of PPROM, especially at an early gestational age. Early recognition is of great interest in the management and prognosis of NCS. PMID:23839604

  10. A Novel Non-Planar Transverse Stretching Process for Micro-Porous PTFE Membranes and Resulting Characteristics

    KAUST Repository

    Chang, Y.-H.

    2018-02-26

    Polytetrafluoroethylene (PTFE) micro-porous membranes were prepared from PTFE fine powder through extruding, rolling, and uniaxial longitudinally stretching. In contrast to conventional planar transverse stretching, a novel 3D mold design of non-planar transverse stretching process was employed in this study to produce micro-porous structure. The morphology, membrane thickness, mean pore size, and porosity of the PTFE membrane were investigated. The results show that the non-planar transverse stretched membranes exhibit more uniform average pore diameter with thinner membrane thickness. Morphological changes induced by planar and non-planar transverse stretching for pore characteristics were investigated. The stretching conditions, stretching temperature and rate, affect the stretched membrane. Increasing temperature facilitated the uniformity of pore size and uniformity of membrane thickness. Moreover, increase in stretching rate resulted in finer pore size and thinner membrane.

  11. Effect of stabilization temperature during pyrolysis process of P84 co-polyimide-based tubular carbon membrane for H2/N2 and He/N2 separations

    Science.gov (United States)

    Sazali, N.; Salleh, W. N. W.; Ismail, A. F.; Ismail, N. H.; Aziz, F.; Yusof, N.; Hasbullah, H.

    2018-04-01

    In this study, the effect of stabilization temperature on the performance of tubular carbon membrane was being investigated. P84 co-polyimide-based tubular carbon membrane will be fabricated through the dip-coating technique. The tubular carbon membrane performance can be controlled by manipulating the pyrolysis conditions which was conducted at different stabilization temperatures of 250, 300, 350, 400, and 450°C under N2 environment (200 ml/min). The prepared membranes were characterized by using scanning electron microscopy (SEM), x-ray diffraction (XRD), and pure gas permeation system. The pure gas of H2, He, and N2 were used to determine the permeation properties of the carbon membrane. The P84 co-polyimide-based tubular carbon membrane stabilized at 300°C demonstrated an excellent permeation property with H2, He, and N2 gas permeance of 1134.51±2.87, 1287.22±2.86 and 2.98±1.28GPU, respectively. The highest H2/N2 and He/N2 selectivity of 380.71±2.34 and 431.95±2.61 was obtained when the stabilization temperature of 450°C was applied. It is concluded that the stabilization temperatures have protrusive effect on the carbon membrane properties specifically their pore structure, and eventually their gas separation properties.

  12. Evaluation of clayey masses compositions starting from the residue incorporation of the red ceramic industry to obtain tubular ceramic membranes

    International Nuclear Information System (INIS)

    Silva, Adriano Lima da; Chaves, Alexsandra Cristina; Luna, Carlos Bruno Barreto; Neves, Gelmires de Araujo; Lira, Helio de Lucena

    2017-01-01

    The inappropriate residue disposal of red ceramic industry is very high. Nowadays, one of the major challenges is the investigation of processes to obtain alternative materials, enabling the use of these residues to manufacture new materials. This work's objective is to study clayey masses' compositions starting from the residue incorporation of the red ceramic industry to be used in tubular ceramic membranes. Two compositions of ceramic masses were established, composition A (50% of residue) and composition B (70% of residue). Granulometric analysis of the ceramic masses presented an average size of particles, what indicates membranes in the microfiltration scale. Another observed factor is related to the increase of residue amount, what favored a decrease in the ceramic mass' plasticity. A rise in the apparent porosity was also observed, probably because of a possible growing in the bigger pores numbers, due to the sintering high temperature and the elevation of residue quantity itself. (author)

  13. Modelling and sequential simulation of multi-tubular metallic membrane and techno-economics of a hydrogen production process employing thin-layer membrane reactor

    KAUST Repository

    Shafiee, Alireza

    2016-09-24

    A theoretical model for multi-tubular palladium-based membrane is proposed in this paper and validated against experimental data for two different sized membrane modules that operate at high temperatures. The model is used in a sequential simulation format to describe and analyse pure hydrogen and hydrogen binary mixture separations, and then extended to simulate an industrial scale membrane unit. This model is used as a sub-routine within an ASPEN Plus model to simulate a membrane reactor in a steam reforming hydrogen production plant. A techno-economic analysis is then conducted using the validated model for a plant producing 300 TPD of hydrogen. The plant utilises a thin (2.5 μm) defect-free and selective layer (Pd75Ag25 alloy) membrane reactor. The economic sensitivity analysis results show usefulness in finding the optimum operating condition that achieves minimum hydrogen production cost at break-even point. A hydrogen production cost of 1.98 $/kg is estimated while the cost of the thin-layer selective membrane is found to constitute 29% of total process capital cost. These results indicate the competiveness of this thin-layer membrane process against conventional methods of hydrogen production. © 2016 Hydrogen Energy Publications LLC

  14. Transverse and lateral distribution of phospholipids and glycolipids in the membrane of the bacterium Micrococcus luteus

    International Nuclear Information System (INIS)

    de Bony, J.; Lopez, A.; Gilleron, M.; Welby, M.; Laneelle, G.; Rousseau, B.; Beaucourt, J.P.; Tocanne, J.F.

    1989-01-01

    The photodimerization of anthracene was used to investigate the transverse and lateral distribution of lipids in the membrane of the Gram-positive bacterium Micrococcus luteus. 9-(2-Anthryl)nonanoic acid (9-AN) is incorporated at a high rate into various membrane lipids of M. luteus. On irradiation of intact bacteria at 360 nm, anthracene-labeled lipids form stable photodimers which can be extracted and separated by thin-layer chromatography. We present here the results of a study on the distribution of two major lipids, phosphatidylglycerol (PG) and dimannosyldiacylglycerol (DMDG), within each leaflet of the membrane lipid bilayer. After metabolic incorporation of a tritiated derivative of 9-AN in M. luteus, the radioactivity associated with the photodimers issued from PG and DMDG was counted. In the bacterial membrane, the ratio of PG-DMDG heterodimer with respect to PG-PG and DMDG-DMDG homodimers is around half of what should be obtained for a homogeneous mixture of the two lipids. In order to find out whether this was due to an asymmetric distribution of the two lipids between the two membrane leaflets or a heterogeneous distribution of the two lipids within the same membrane leaflet, the transverse distribution of PG and DMDG was also investigated. This was carried out by following the kinetics of oxidation of the two lipids by periodic acid in the membrane of M. luteus protoplasts. PG predominated slightly in the outer layer (60%), while DMDG was found to be symmetrically distributed between the two leaflets. By itself, this lipid asymmetry cannot account for the lipid distribution determined from the photodimerization experiments. This indicates that PG and DMDG are not homogeneously distributed in the plane of the bacterial membrane

  15. Construction and characterization of an electrospun tubular scaffold for small-diameter tissue-engineered vascular grafts: a scaffold membrane approach.

    Science.gov (United States)

    Hu, Jin-Jia; Chao, Wei-Chih; Lee, Pei-Yuan; Huang, Chih-Hao

    2012-09-01

    Based on a postulate that the microstructure of a scaffold can influence that of the resulting tissue and hence its mechanical behavior, we fabricated a small-diameter tubular scaffold (∼3 mm inner diameter) that has a microstructure similar to the arterial media using a scaffold membrane approach. Scaffold membranes that contain randomly oriented, moderately aligned, or highly aligned fibers were fabricated by collecting electrospun poly([epsilon]-caprolactone) fibers on a grounded rotating drum at three different drum rotation speeds (250, 1000, and 1500 rpm). Membranes of each type were wrapped around a small-diameter mandrel to form the tubular scaffolds. Particularly, the tubular scaffolds with three different off-axis fiber angles (30, 45, and 60 degree) were formed using membranes that contain aligned fibers. These scaffolds were subjected to biaxial mechanical testing to examine the effects of fiber directions as well as the distribution of fiber orientations on their mechanical properties. The circumferential elastic modulus of the tubular scaffold was closely related to the fiber directions; the larger the off-axis fiber angle the greater the circumferential elastic modulus. The distribution of fiber orientations, on the other hand, manifested itself in the mechanical behavior via the Poisson effect. Similar to cell sheet-based vascular tissue engineering, tubular cell-seeded constructs were prepared by wrapping cell-seeded scaffold membranes, alleviating the difficulty associated with cell seeding in electrospun scaffolds. Histology of the construct illustrated that cells were aligned to the fiber directions in the construct, demonstrating the potential to control the microstructure of tissue-engineered vascular grafts using the electrospun scaffold membrane. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. ARSENIC DETERMINATION IN SALINE WATERS UTILIZING A TUBULAR MEMBRANE AS A GAS-LIQUID SEPATRATOR FOR HYDRIDE GENERATION INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY

    Science.gov (United States)

    A tubular silicone rubber membrane is evaluated as a gas-liquid separator for the determination of arsenic in saline waters via HG-ICP-MS. The system was optimized in terms of NaBH and HCI concentrations. The intermediate gas and carrier gas were optimized in terms of sensitiity ...

  17. Sheet-Like Remodeling of the Transverse Tubular System in Human Heart Failure Impairs Excitation-Contraction Coupling and Functional Recovery by Mechanical Unloading.

    Science.gov (United States)

    Seidel, Thomas; Navankasattusas, Sutip; Ahmad, Azmi; Diakos, Nikolaos A; Xu, Weining David; Tristani-Firouzi, Martin; Bonios, Michael J; Taleb, Iosif; Li, Dean Y; Selzman, Craig H; Drakos, Stavros G; Sachse, Frank B

    2017-04-25

    Cardiac recovery in response to mechanical unloading by left ventricular assist devices (LVADs) has been demonstrated in subgroups of patients with chronic heart failure (HF). Hallmarks of HF are depletion and disorganization of the transverse tubular system (t-system) in cardiomyocytes. Here, we investigated remodeling of the t-system in human end-stage HF and its role in cardiac recovery. Left ventricular biopsies were obtained from 5 donors and 26 patients with chronic HF undergoing implantation of LVADs. Three-dimensional confocal microscopy and computational image analysis were applied to assess t-system structure, density, and distance of ryanodine receptor clusters to the sarcolemma, including the t-system. Recovery of cardiac function in response to mechanical unloading was assessed by echocardiography during turndown of the LVAD. The majority of HF myocytes showed remarkable t-system remodeling, particularly sheet-like invaginations of the sarcolemma. Circularity of t-system components was decreased in HF versus controls (0.37±0.01 versus 0.46±0.02; P 1 µm did not improve after mechanical unloading. In addition, calcium transients were recorded in field-stimulated isolated human cardiomyocytes and analyzed with respect to local t-system density. Calcium release in HF myocytes was restricted to regions proximal to the sarcolemma. Local calcium upstroke was delayed (23.9±4.9 versus 10.3±1.7 milliseconds; P human HF presents a characteristic novel phenotype consisting of sheet-like invaginations of the sarcolemma. Our results suggest that the remodeled t-system impairs excitation-contraction coupling and functional recovery during chronic LVAD unloading. An intact t-system at the time of LVAD implantation may constitute a precondition and predictor for functional cardiac recovery after mechanical unloading. © 2017 American Heart Association, Inc.

  18. Heat-And-Mass Transfer Relationship to Determine Shear Stress in Tubular Membrane Systems

    DEFF Research Database (Denmark)

    Ratkovich, Nicolas Rios; Nopens, Ingmar

    2012-01-01

    The main drawback of Membrane Bioreactors (MBRs) is the fouling of the membrane. One way to reduce this fouling is through controlling the hydrodynamics of the two-phase slug flow near the membrane surface. It has been proven in literature that the slug flow pattern has a higher scouring effect...... measurements are required. Therefore, this work proposes an alternative method that uses already existing heat transfer relationships for two phase flow and links them through a dimensionless number to the mass transfer coefficient (Sherwood number) to obtain an empirical relationship which can be used...

  19. Analysis of Shear Stress and Energy Consumption in a Tubular Airlift Membrane System

    DEFF Research Database (Denmark)

    Ratkovich, Nicolas Rios; Chan, C.C.V.; Berube, P.R.

    2011-01-01

    Application of a two-phase slug flow in side-stream membrane bioreactors (MBRs) has proven to increase the permeate flux and decrease fouling through a better control of the cake layer. Past literature has shown that the hydrodynamics near the membrane surface have an impact on the degree...... of fouling by imposing high shear stress near the surface of the membrane. Previously, shear stress histograms (SSH) have been introduced to summarize results from an experimental setup developed to investigate the shear stress imposed on the surface of a membrane under different two-phase flow conditions...... (gas and liquid) by varying the flow of each phase. Bimodal SSHs were observed, with peaks corresponding to the shear induced by the liquid and gas flow respectively. In this contribution, SSHs are modelled using simple empirical relationships. These are used to identify the two-phase flow conditions...

  20. Conceptual bases of creation of the membrane device of tubular type for studying the in bioreactors

    Directory of Open Access Journals (Sweden)

    A. I. Klyuchnikov

    2017-01-01

    Full Text Available In this study, methods for intensifying micro- and ultrafiltration processes by controlling the concentration-polarization effect are considered and studied. The negative effect of concentration polarization on the process of separation of the filtered liquid and on the membrane surface is described (due to the increase in concentration, the selectivity and specific productivity of the membrane surface decrease. The physical picture of the flowing phenomena in a flat membrane channel with known geometric dimensions is considered, four sections with different effects on the filtration process are identified. The equation of material balance is analyzed by introducing boundary conditions into the criterion equation of material balance, with the aim of finding opportunities for mass transfer. It is revealed that the mass transfer coefficient km decreases, due to the growth of the thickness of the boundary layer. The main parameters significantly influencing the process of microfiltration are the flow rates G of the initial solution, the mass transfer coefficient km, and with decreasing km decreases and G. The analysis of theoretical and experimental data is carried out showing that the decisive role in the course of the microfiltration process is played by the motion regime of the initial solution, Physical-chemical properties, geometry of the membrane channel. The prospects for using the pulsating field in bioreactors and the need for a conceptual approach for the development of promising membrane devices are grounded. The need to create membranes of complex geometric shapes with the possibility of placing turbulent devices in them and the possibility of moving them relative to each other is considered, creating channels of variable cross-section, which will lead to the appearance of a sufficient number of possibilities for creating hydrodynamic instabilities of various intensities. The article touches upon the application of pulsation regimes of

  1. Spectrophotometric flow-injection determination of sulphite in white wines involving gas diffusion through a concentric tubular membrane

    Directory of Open Access Journals (Sweden)

    Melo Denise

    2003-01-01

    Full Text Available A flow-injection system is proposed for the spectrophotometric determination of sulphite in white wines. The method involves analyte conversion to SO2, gas diffusion through a Teflon® semi-permeable membrane, collection into an alkaline stream (pH 8, reaction with Malachite green (MG and monitoring at 620 nm. With a concentric tubular membrane, the system design was simplified. Influence of reagent concentrations, pH of donor and acceptor streams, temperature, timing, surfactant addition and presence of potential interfering species of the wine matrix were investigated. A pronounced (ca. 100% enhancement in sensitivity was noted by adding cetylpyridinium chloride (CPC. The proposed system is robust and baseline drift is not observed during 4 h operating periods. Only 400 muL of sample and 0.32 mg MG are required per determination. The system handles 30 samples per hour, yielding precise results (r.s.d. < 0.015 for 1.0 - 20.0 mg L-1 SO2 in agreement with those obtained by an alternative procedure.

  2. Crossflow ultrafiltration of raw municipal wastewater : Investigations using PVDF tubular membranes

    NARCIS (Netherlands)

    Ravazzini, A.M.

    2008-01-01

    In the usual wastewater treatment schemes the application of membranes follows a biological process. However, ultrafiltration of untreated wastewater produces permeate free of particles and bacteria in one single step and could represent the starting point for new water-reuse concepts. This thesis

  3. Comparison of transverse island flap onlay and tubularized incised-plate urethroplasties for primary proximal hypospadias: a systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Dongdong Xiao

    Full Text Available PURPOSE: This meta-analysis was conducted to compare postoperative outcomes between transverse island flap (TVIF onlay and tubularized incised-plate (TIP urethroplasties for primary proximal hypospadias. MATERIALS AND METHODS: A comprehensive literature search updated to 21st May 2014 was carried out for relevant studies. After literature identification and data extraction, odds ratio (OR with 95% confidential interval (CI was calculated to compare postoperative complication rate between TVIF onlay and TIP. Meta-regression and subgroup analyses were applied to find potential affective factors. RESULTS: A total of 6 studies including 309 patients receiving TVIF onlay and 262 individuals subjected to TIP met inclusion criteria. The synthetic data suggested that TVIF onlay and TIP were comparable in terms of total complication rate (OR 0.85, 95% CI 0.56-1.30, p = 0.461, fistula (OR 0.68, 95% CI 0.38-1.21, p = 0.194, recurrent curvature (OR 1.16, 95% CI 0.43-3.12, p = 0.766, dehiscence (OR 0.95, 95% CI 0.33-2.74, p = 0.920, diverticulum (OR 1.90, 95% CI 0.53-6.78, p = 0.321, meatal stenosis (OR 0.74, 95% CI 0.20-2.77, p = 0.651 and urethral stricture (OR 1.49, 95% CI 0.41-5.50, p = 0.545, without significant heterogeneity for each comparison group. Meta-regression and subgroup analyses revealed no significant findings. One-way sensitivity analysis indicated that the results were stable. No publication bias was detected using both funnel plot and Egger's test. Also, there were no obvious differences observed in cosmetic and functional outcomes. CONCLUSIONS: This meta-analysis suggests that TVIF onlay and TIP urethroplasties are clinically equivalent. Given the inherent limitations of included studies, this conclusion should be interpreted with caution and wait to be confirmed by more well-designed randomized controlled trials with high quality in the future.

  4. Giant cell tubulitis with tubular basement membrane immune deposits: a report of two cases after cardiac valve replacement surgery.

    Science.gov (United States)

    Chang, Anthony; Peutz-Kootstra, Carine J; Kowalewska, Jolanta; Logar, Christine M; Gitomer, Jeremy J; Davis, Connie L; Shankland, Stuart J; Alpers, Charles E; Smith, Kelly D

    2006-09-01

    This paper presents two elderly patients who had normal baseline renal function and had stenotic valvular lesions secondary to rheumatic fever and underwent aortic valve replacements with mechanical valves. Both patients developed acute renal failure after cardiac valve replacement procedures. The renal biopsies revealed acute granulomatous tubulointerstitial nephritis. The unique histologic features were tubular basement membrane (TBM) immune complex deposition detected by both immunofluorescence and electron microscopy and prominent multinucleated giant cells surrounding intact TBM. The temporal relationship to the surgical procedure and the subsequent recovery of the patients' renal functions upon therapy suggested that the renal failure may have been due to an allergic drug reaction from the perioperative exposure to unknown agents, such as prophylactic antibiotics and furosemide. The literature on TBM immune complex deposition was reviewed, and the pathophysiologic mechanisms that may account for the similarities between the clinicopathologic features of these two cases were examined. These two cases expand the histopathologic spectrum of previously described cases of putative drug-induced acute tubulointerstitial nephritis.

  5. Modification of the Selectivity Properties of Tubular Ceramic Membranes after Alkaline Treatment

    Directory of Open Access Journals (Sweden)

    Patrick Dutournié

    2017-11-01

    Full Text Available This work focuses on the selectivity modification of ceramic membranes after a mild alkaline treatment. Filtration of pure salt-water solutions was carried out with commercial titania membranes before and after the treatment. After treatment, the rejection of NaF significantly decreased, while the rejection of NaCl and NaBr increased. Additionally, NaI and Na2SO4 remained close to zero. Pore size and electrical charge being almost unchanged, only significant modifications in the dielectric effects can explain this modification of selectivity. Therefore, the surface chemistry and the interaction (nature and magnitude with the solvent and with the species present in the solution appear to be modified by the alkaline treatment. This trend is also illustrated by discussing the electric and the dielectric properties that were numerically identified before and after treatment. The alkaline treatment significantly decreased the apparent dielectric constant of NaCl-water solution in the pore, highlighting the rejection of sodium chloride. Contrariwise, the modification of the surface chemistry increased the apparent dielectric constant of NaF-water solution by promoting fluoride transmission.

  6. Van der Waals interactions between planar substrate and tubular lipid membranes undergoing pearling instability

    Science.gov (United States)

    Valchev, G. S.; Djondjorov, P. A.; Vassilev, V. M.; Dantchev, D. M.

    2017-10-01

    In the current article we study the behavior of the van der Waals force between a planar substrate and an axisymmetric bilayer lipid membrane undergoing pearling instability, caused by uniform hydrostatic pressure difference. To do so, the recently suggested "surface integration approach" is used, which can be considered a generalization of the well known and widely used Derjaguin approximation. The static equilibrium shape after the occurrence of the instability is described in the framework of Helfrich's spontaneous curvature model. Some specific classes of exact analytical solutions to the corresponding shape equation are considered, and the components of the respective position vectors given in terms of elliptic integrals and Jacobi elliptic functions. The mutual orientation between the interacting objects is chosen such that the axis of revolution of the distorted cylinder be parallel to the plane bounding the substrate. Based on the discussed models and approaches we made some estimations for the studied force in real experimentally realizable systems, thus showing the possibility of pearling as an useful technique for reduction of the adhesion in variety of industrial processes using lipid membranes as carriers.

  7. Performance and mechanisms for the removal of phthalates and pharmaceuticals from aqueous solution by graphene-containing ceramic composite tubular membrane coupled with the simultaneous electrocoagulation and electrofiltration process.

    Science.gov (United States)

    Yang, Gordon C C; Chen, Ying-Chun; Yang, Hao-Xuan; Yen, Chia-Heng

    2016-07-01

    In this study, commonly detected emerging contaminants (ECs) in water, including di-n-butyl phthalate (DnBP), di(2-ethylhexyl) phthalate (DEHP), cephalexin (CLX), sulfamethoxazole (SMX) and caffeine (CAF), were selected as the target contaminants. A lab-prepared graphene-containing ceramic composite tubular membrane (TGCCM) coupled with the simultaneous electrocoagulation and electrofiltration process (EC/EF) in crossflow filtration mode was used to remove target contaminants in model solution. Meanwhile, a comparison of the removal efficiency was made among various tubular composite membranes reported, including carbon fibers/carbon/alumina composite tubular membrane (TCCACM), titania/alumina composite tubular membrane (TTACM) and alumina tubular membrane (TAM). The results of this study showed that the removal efficiencies for DnBP and DEHP were 99%, whereas 32-97% for cephalexin (CLX), sulfamethoxazole (SMX) and caffeine (CAF). In this work the mechanisms involved in removing target ECs were proposed and their roles in removing various ECs were also discussed. Further, two actual municipal wastewaters were treated to evaluate the applicability of the aforementioned treatment technology (i.e., TGCCM coupled with EC/EF) to various aqueous solutions in the real world. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Tubular combustion

    CERN Document Server

    Ishizuka, Satoru

    2014-01-01

    Tubular combustors are cylindrical tubes where flame ignition and propagation occur in a spatially confined, highly controlled environment, in a nearly flat, elongated geometry. This allows for some unique advantages where extremely even heat dispersion is required over a large surface while still maintaining fuel efficiency. Tubular combustors also allow for easy flexibility in type of fuel source, allowing for quick changeover to meet various needs and changing fuel pricing. This new addition to the MP sustainable energy series will provide the most up-to-date research on tubular combustion--some of it only now coming out of private proprietary protection. Plentiful examples of current applications along with a good explanation of background theory will offer readers an invaluable guide on this promising energy technology. Highlights include: * An introduction to the theory of tubular flames * The "how to" of maintaining stability of tubular flames through continuous combustion * Examples of both small-scal...

  9. Hydrogen-Permeable Tubular Membrane Reactor: Promoting Conversion and Product Selectivity for Non-Oxidative Activation of Methane over an Fe©SiO2Catalyst.

    Science.gov (United States)

    Sakbodin, Mann; Wu, Yiqing; Oh, Su Cheun; Wachsman, Eric D; Liu, Dongxia

    2016-12-23

    Non-oxidative methane conversion over Fe©SiO 2 catalyst was studied for the first time in a hydrogen (H 2 ) permeable tubular membrane reactor. The membrane reactor is composed of a mixed ionic-electronic SrCe 0.7 Zr 0.2 Eu 0.1 O 3-δ thin film (≈20 μm) supported on the outer surface of a one-end capped porous SrCe 0.8 Zr 0.2 O 3-δ tube. Significant improvement in CH 4 conversion was achieved upon H 2 removal from the membrane reactor compared to that in a fixed-bed reactor. The Fe©SiO 2 catalyst in the H 2 permeable membrane reactor demonstrated a stable ≈30 % C 2+ single-pass yield, with up to 30 % CH 4 conversion and 99 % selectivity to C 2 (ethylene and acetylene) and aromatic (benzene and naphthalene) products, at the tested conditions. The selectivity towards C 2 or aromatics was manipulated purposely by adding H 2 into or removing H 2 from the membrane reactor feed and permeate gas streams. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Ultrasound measurement of the transverse diameter of the fetal thymus in pregnancies complicated by the preterm prelabor rupture of membranes.

    Science.gov (United States)

    Musilova, Ivana; Hornychova, Helena; Kostal, Milan; Jacobsson, Bo; Kacerovsky, Marian

    2013-06-01

    To determine whether the measurement of the transverse diameter of the fetal thymus is of value in the identification of either histologic chorioamnionitis or funisitis in pregnancies complicated by preterm prelabor rupture of membranes (PPROM). The transverse diameter of the fetal thymus was measured in 216 fetuses from PPROM pregnancies. A small thymus was defined as a transverse thymic diameter below the fifth percentile according to a previously published nomogram. The placenta, the fetal membranes, and the umbilical cord were assessed for the presence of inflammation. A small thymus was identified in 69% (150/216) of fetuses. A small thymus was present in 80% (106/133) and 88% (36/41) of women with histologic chorioamnionitis or funisitis, respectively. The presence of a small thymus had a sensitivity of 79%, specificity of 47%, positive predictive value of 71%, negative predictive value of 59% for the identification of chorioamnionitis (p value of 24%, and negative predictive value of 92% in the identification of funisitis (p = 0.004; odds ratio 4.4). The sonographic finding of a small thymus is a sensitive indicator of histologic chorioamnionitis or funisitis; low specificity excludes it as a possible clinical implication in the management of PPROM pregnancies. Copyright © 2013 Wiley Periodicals, Inc.

  11. Experimental, kinetic and numerical modeling of hydrogen production by catalytic reforming of crude ethanol over a commercial catalyst in packed bed tubular reactor and packed bed membrane reactor

    International Nuclear Information System (INIS)

    Aboudheir, Ahmed; Akande, Abayomi; Idem, Raphael

    2006-01-01

    The demand for hydrogen energy has increased tremendously in recent years essentially because of the increase in the word energy consumption as well as recent developments in fuel cell technologies. The energy information administration has projected that world energy consumption will increase by 59% over the next two decades, from 1999 to 2020, in which the largest share is still dominated by fossil fuels (oil, natural gas and coal). Carbon dioxide (CO 2 ) emissions resulting from the combustion of these fossil fuels currently are estimated to account for three-fourth of human-caused CO 2 emissions worldwide. Greenhouse gas emission, including CO 2 , should be limited, as recommended at the Kyoto Conference, Japan, in December 1997. In this regard, hydrogen (H 2 ) has a significant future potential as an alternative fuel that can solve the problems of CO 2 emissions as well as the emissions of other air contaminants. One of the techniques to produce hydrogen is by reforming of hydrocarbons or biomass. Crude ethanol (a form of biomass, which essentially is fermentation broth) is easy to produce, is free of sulphur, has low toxicity, and is also safe to handle, transport and store. In addition, crude ethanol consists of oxygenated hydrocarbons, such as ethanol, lactic acid, glycerol, and maltose. These oxygenated hydrocarbons can be reformed completely to H 2 and CO 2 , the latter of which could be separated from H 2 by membrane technology. This provides for CO 2 capture for eventual storage or destruction. In the case of using crude ethanol, this will result in negative CO 2 , emissions. In this paper, we conducted experimental work on production of hydrogen by the catalytic reforming of crude ethanol over a commercial promoted Ni-based catalyst in a packed bed tubular reactor as well as a packed bed membrane reactor. As well, a rigorous numerical model was developed to simulate this process in both the catalytic packed bed tubular reactor and packed bed membrane

  12. Gestational Undernourishment Modifies the Composition of Skeletal Muscle Transverse Tubule Membranes and the Mechanical Properties of Muscles in Newborn Rats

    Directory of Open Access Journals (Sweden)

    Ricardo Tonathiu Ramírez-Oseguera

    2013-10-01

    Full Text Available Backgroud/Aims: Skeletal muscle (SM constitutes more than 40% of the body weight in adulthood. Transports dietary glucose mainly through the insulin-dependent glucose transporter (Glut-4 located in the Transverse tubule membrane system (TT. The TT development ends shortly after birth. The TT membrane hosts the proteins involved in excitation-contraction coupling and glucose uptake. Glycaemic regulation through movement is a key function of fully developed skeletal muscle. In this study, we aimed to characterize the effect of gestational undernourishment (GUN in rats GLUT-4 expression and on the protein/lipid content of the TT membranes. We also examined the effect of GUN on the mechanical properties of muscles as an indication of the metabolic condition of the SM at birth. Methods: Isolated TT membrane from SM of GUN rats were used to study lipid/protein content and protein stability by differential scanning calorimetry. The effect of GUN on the SM mechanical properties was determined in isolated Extensor Digitorum Longus (EDL muscle. Results: We demonstrate that compared to control, GUN in the new-born produces; i decreases body weight; ii diminution in SM mass; iii decreases the formation of TT membranes; iv expresses TT membrane proteins with higher thermal stability. The TT membrane expression of GLUT-4 in GUN offspring was twice that of controls. The isolated EDL of GUN offspring was 20% stronger as measured by contractile force and more resistant to fatigue relative to controls. Conclusion; These results provide the first evidence of adaptive changes of the SM in new-borns exposed to severe gestational food restriction. The effects of GUN on muscle at birth are the first step toward detrimental SM metabolic function, contributing to the physiopathology of metabolic diseases in adulthood.

  13. Skin Layer at the Actin-Gel Surface: Quenched Protein Membranes with Flat, Crumpled and Tubular Morphologies

    Science.gov (United States)

    Hirst, L. S.

    2004-03-01

    The actin cytoskeleton is a major component of eukaryotic cells involved in key functions including cell shape and mechanical stability. We report on the discovery of a novel hierarchically structured skin-layer formed at the surface of an isotropic gel of filamentous actin bundles at high molar ratios of alpha-actinin, an actin cross-linking protein, to globular actin. Laser scanning confocal microscopy has elucidated the full 3D structure on the micron scale. The protein skin-layer, composed of a directed network of bundles, exhibits flat, crumpled and remarkable, tube-like and pleated multi-tubular morphologies, resulting from stresses due to the underlying gel. These biologically based geometric structures, which may freely detach from the gel, demonstrate potential for the generation of scaffolds with defined shapes for applications in tissue engineering and templating. Supported by NSF DMR-0203755 and CTS 0103516 and NIH GM59288.

  14. Preparation and characterization of micro-cell membrane chromatographic column with N-hydroxysuccinimide group-modified silica-based porous layer open tubular capillary.

    Science.gov (United States)

    Xu, Liang; Xu, Bei; Zhao, Zhi-Yu; Yang, Hui-Ping; Tang, Cheng; Dong, Lin-Yi; Liu, Kun; Fu, Li; Wang, Xian-Hua

    2017-09-22

    Cell membrane chromatography (CMC) is an effective tool in screening active compounds from natural products and studying membrane protein interactions. Nevertheless, it always consumes a large amount of cells (e.g. 10 7 -10 8 ) for column preparation. To overcome this, micro-CMC (mCMC), that employs a silica capillary as membrane carrier, was developed. However, both CMC and mCMC suffer from short column life span (e.g. 3days), mainly due to the falling-off of cellular membranes (CMs). This has greatly limited further application of CMC and mCMC, especially when the cells are hard to obtain. To solve this, N-hydroxysuccinimide (NHS)-modified silica-based porous layer open tubular capillary was first prepared for mCMC. The NHS groups can easily react with amino groups on CMs to form a stable covalent bond under a mild condition. So, CMs immobilized on the NHS-modified capillary are less likely to fall off. To verify this, SKBR3/mCMC (Her2 positive) and BALL1/mCMC (CD20 positive) columns were prepared. Two monoclonal antibody drugs, trastuzumab (anti-Her2) and rituximab (anti-CD20), were selected as analytes to characterize the columns. As a result, NHS-modified column for mCMC can afford higher chromatographic retention than non-modified column. Besides, the column life span was significantly improved to more than 16days for SKBR3/mCMC and 14days for BALL1/mCMC, while the compared column showed a sharp decline in retention factor in first 3days. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Preparative fractionation of protein, RNA, and plasmid DNA using centrifugal precipitation chromatography with tubular dialysis membrane inside a convoluted tubing as separation channel.

    Science.gov (United States)

    Tomanee, Panarat; Hsu, James T; Ito, Yoichiro

    2006-01-01

    Fractionation of clarified E. coli lysate components in bench-scale and preparative-scale centrifugal precipitation chromatography (CPC), using a solution of cationic surfactant cetyltrimethylammonium bromide (CTAB) containing 0.5 M NaCl as precipitant, are compared here. Step gradient of CTAB from 0.50% to 0.16% (w/v) gave a successful fractionation in bench-scale CPC; however, a linear gradient of lower CTAB concentration, 0.20-0% (w/v), was used in the preparative scale and resulted in similar fractionation. The preparative-scale CPC has a superior sample loading capacity by the use of tubular dialysis membrane inside convoluted tubing as the separation channel. In this study, the quantity of the sample loaded into the preparative CPC was about 15 times more than that in the bench scale, and in a single run the preparative CPC could prepare approximately 3 mg of plasmid DNA with about 96% of RNA removed. The higher surface area per length of the separation channel in the preparative CPC was believed to benefit mass transfer of CTAB across the membrane, leading to less CTAB being required in the process.

  16. Modeling the Transverse Shell-side Mass Transfer in Hollow Fiber Membrane Contactors at Low Reynolds Numbers

    Science.gov (United States)

    Kirsch, V. A.; Volkov, V. V.; Bildukevich, A. V.

    A method for calculating the external mass transfer in a contactor with a transverse confined flow of a viscous incompressible liquid (gas) past hollow fibers at low Reynolds numbers is proposed. The method is based on the concept of regular arrays of parallel fibers with a well-defined flowfield. As a simplest model system, a row of parallel fibers is considered, for which dependences of a drag force and an efficiency of a solute retention on the inter-fiber distance, membrane mass transfer coefficient, Peclet and Reynolds numbers are computed. The influence of the fluid inertia on the mass transport is studied. It is shown that a linear Stokes equations can be used for as higher Re numbers, as denser is the fiber array. In this case the flow field is independent on the Re number, and analytical solutions for the flowfield and fiber sorption efficiency (fiber Sherwood number) can be used.

  17. Application of high speed imaging as a novel tool to study particle dynamics in tubular membrane systems

    NARCIS (Netherlands)

    Lindeboom, R.E.F.; Smith, G.; Jeison, D.A.; Temmink, B.G.; Lier, van J.B.

    2011-01-01

    Membrane bioreactors represent a promising technology for wastewater treatment, already applied to a wide variety of industrial effluents and sewage. Gas or air sparging is a commonly applied approach to generate surface shear to control fouling phenomena and cake formation causing flux reduction.

  18. Application of high speed imaging as a novel tool to study particle dynamics in tubular membrane systems

    NARCIS (Netherlands)

    Lindeboom, R.; Smith, G.; Jeison, D.; Temmink, H.; Van Lier, J.B.

    2010-01-01

    Membrane bioreactors represent a promising technology for wastewater treatment, already applied to a wide variety of industrial effluents and sewage. Gas or air sparging is a commonly applied approach to generate surface shear to control fouling phenomena and cake formation causing flux reduction.

  19. NHE- and diffusion-dependent proton fluxes across the tubular system membranes of fast-twitch muscle fibers of the rat.

    Science.gov (United States)

    Launikonis, Bradley S; Cully, Tanya R; Csernoch, Laszlo; Stephenson, D George

    2018-01-02

    The complex membrane structure of the tubular system (t-system) in skeletal muscle fibers is open to the extracellular environment, which prevents measurements of H + movement across its interface with the cytoplasm by conventional methods. Consequently, little is known about the t-system's role in the regulation of cytoplasmic pH, which is different from extracellular pH. Here we describe a novel approach to measure H + -flux measurements across the t-system of fast-twitch fibers under different conditions. The approach involves loading the t-system of intact rat fast-twitch fibers with a strong pH buffer (20 mM HEPES) and pH-sensitive fluorescent probe (10 mM HPTS) before the t-system is sealed off. The pH changes in the t-system are then tracked by confocal microscopy after rapid changes in cytoplasmic ionic conditions. T-system sealing is achieved by removing the sarcolemma by microdissection (mechanical skinning), which causes the tubules to pinch off and seal tight. After this procedure, the t-system repolarizes to physiological levels and can be electrically stimulated when placed in K + -based solutions of cytosolic-like ionic composition. Using this approach, we show that the t-system of fast-twitch skeletal fibers displays amiloride-sensitive Na + /H + exchange (NHE), which decreases markedly at alkaline cytosolic pH and has properties similar to that in mammalian cardiac myocytes. We observed mean values for NHE density and proton permeability coefficient of 339 pmol/m 2 of t-system membrane and 158 µm/s, respectively. We conclude that the cytosolic pH in intact resting muscle can be quantitatively explained with respect to extracellular pH by assuming that these values apply to the t-system membrane and the sarcolemma. © 2018 Launikonis et al.

  20. Modelling of a tubular membrane contactor for pre-combustion CO2 capture using ionic liquids: Influence of the membrane configuration, absorbent properties and operation parameters

    Directory of Open Access Journals (Sweden)

    Zhongde Dai

    2016-10-01

    Full Text Available A membrane contactor using ionic liquids (ILs as solvent for pre-combustion capture CO2 at elevated temperature (303–393 K and pressure (20 bar has been studied using mathematic model in the present work. A comprehensive two-dimensional (2D mass-transfer model was developed based on finite element method. The effects of liquid properties, membrane configurations, as well as operation parameters on the CO2 removal efficiency were systematically studied. The simulation results show that CO2 can be effectively removed in this process. In addition, it is found that the liquid phase mass transfer dominated the overall mass transfer. Membranes with high porosity and small thickness could apparently reduce the membrane resistance and thus increase the separation efficiency. On the other hand, the membrane diameter and membrane length have a relatively small influence on separation performance within the operation range. Keywords: CO2 capture, Pre-combustion, Membrane contactor, Ionic liquids, Modelling

  1. Cooperation of the ER-shaping proteins atlastin, lunapark, and reticulons to generate a tubular membrane network.

    Science.gov (United States)

    Wang, Songyu; Tukachinsky, Hanna; Romano, Fabian B; Rapoport, Tom A

    2016-09-13

    In higher eukaryotes, the endoplasmic reticulum (ER) contains a network of membrane tubules, which transitions into sheets during mitosis. Network formation involves curvature-stabilizing proteins, including the reticulons (Rtns), as well as the membrane-fusing GTPase atlastin (ATL) and the lunapark protein (Lnp). Here, we have analyzed how these proteins cooperate. ATL is needed to not only form, but also maintain, the ER network. Maintenance requires a balance between ATL and Rtn, as too little ATL activity or too high Rtn4a concentrations cause ER fragmentation. Lnp only affects the abundance of three-way junctions and tubules. We suggest a model in which ATL-mediated fusion counteracts the instability of free tubule ends. ATL tethers and fuses tubules stabilized by the Rtns, and transiently sits in newly formed three-way junctions. Lnp subsequently moves into the junctional sheets and forms oligomers. Lnp is inactivated by mitotic phosphorylation, which contributes to the tubule-to-sheet conversion of the ER.

  2. The influence of ultrasound on wine and wine materials acidity during clarification process in tubular membrane filters

    Directory of Open Access Journals (Sweden)

    A. A. Ponedelchenko

    2016-01-01

    Full Text Available Researches on the experimental ultrasonic installation were carried out, using industrial equipment for bottling liquids and ultrasonic apparatus "Volna-M" UZTA-1/22-OM, for clarification and filtering of table wines by tangential microfiltration using membrane ceramic filtering elements with a pore size of 0.2 micron at a pressure of 0.5-2.0 bar. Membrane ultrafiltration upon application of ultrasound of 30-40 microns amplitude and a frequency of 20 kHz ± 1.65 Hz at high filter performance and work stability changes the quantitative content of the valuable wine components slightly. But much attention to the increase of titratable acidity and pH medium due to possible degradation and esterification intensification of higher acids and alcohols was paid. At the same time more intense and rich aroma and distinct flavor with berry notes appears in wine that along with the physical- and chemical indicators helped to improve organoleptic characteristics and to increase the tasting evaluation of wines. At the same time, the content of phenolic and nitrogen compounds is reduced resulting in wines stability to protein and colloidal opacification. It became possible to refuse multiple regeneration of ceramic filter elements for the  ecovery of their performance, as well as the use of preservatives and antiseptics at a high wines bottling stability. It is shown that the filtration with the dosing of ultrasound in the wine industry allows not only reducing the cost of consumables, equipment and removing some of the traditional processes, but also providing the cold sterilization of wine materials with an increase in their quality.

  3. The Use of Fibrous, Supramolecular Membranes and Human Tubular Cells for Renal Epithelial Tissue Engineering : Towards a Suitable Membrane for a Bioartificial Kidney

    NARCIS (Netherlands)

    Dankers, Patricia Y. W.; Boomker, Jasper M.; Huizinga-van der Vlag, Ali; Smedts, Frank M. M.; Harmsen, Martin C.; van Luyn, Marja J. A.

    2010-01-01

    A bioartificial kidney, which is composed of a membrane cartridge with renal epithelial cells, can substitute important kidney functions in patients with renal failure. A particular challenge is the maintenance of monolayer integrity and specialized renal epithelial cell functions ex vivo. We

  4. Transverse relaxation dispersion of the p7 membrane channel from hepatitis C virus reveals conformational breathing

    International Nuclear Information System (INIS)

    Dev, Jyoti; Brüschweiler, Sven; Ouyang, Bo; Chou, James J.

    2015-01-01

    The p7 membrane protein encoded by hepatitis C virus (HCV) assembles into a homo-hexamer that selectively conducts cations. An earlier solution NMR structure of the hexameric complex revealed a funnel-like architecture and suggests that a ring of conserved asparagines near the narrow end of the funnel are important for cation interaction. NMR based drug-binding experiments also suggest that rimantadine can allosterically inhibit ion conduction via a molecular wedge mechanism. These results suggest the presence of dilation and contraction of the funnel tip that are important for channel activity and that the action of the drug is attenuating this motion. Here, we determined the conformational dynamics and solvent accessibility of the p7 channel. The proton exchange measurements show that the cavity-lining residues are largely water accessible, consistent with the overall funnel shape of the channel. Our relaxation dispersion data show that residues Val7 and Leu8 near the asparagine ring are subject to large chemical exchange, suggesting significant intrinsic channel breathing at the tip of the funnel. Moreover, the hinge regions connecting the narrow and wide regions of the funnel show strong relaxation dispersion and these regions are the binding sites for rimantadine. Presence of rimantadine decreases the conformational dynamics near the asparagine ring and the hinge area. Our data provide direct observation of μs–ms dynamics of the p7 channel and support the molecular wedge mechanism of rimantadine inhibition of the HCV p7 channel

  5. Transverse relaxation dispersion of the p7 membrane channel from hepatitis C virus reveals conformational breathing

    Energy Technology Data Exchange (ETDEWEB)

    Dev, Jyoti; Brüschweiler, Sven [Harvard Medical School, Department of Biological Chemistry and Molecular Pharmacology (United States); Ouyang, Bo [Chinese Academy of Sciences, State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology (China); Chou, James J., E-mail: james-chou@hms.harvard.edu [Harvard Medical School, Department of Biological Chemistry and Molecular Pharmacology (United States)

    2015-04-15

    The p7 membrane protein encoded by hepatitis C virus (HCV) assembles into a homo-hexamer that selectively conducts cations. An earlier solution NMR structure of the hexameric complex revealed a funnel-like architecture and suggests that a ring of conserved asparagines near the narrow end of the funnel are important for cation interaction. NMR based drug-binding experiments also suggest that rimantadine can allosterically inhibit ion conduction via a molecular wedge mechanism. These results suggest the presence of dilation and contraction of the funnel tip that are important for channel activity and that the action of the drug is attenuating this motion. Here, we determined the conformational dynamics and solvent accessibility of the p7 channel. The proton exchange measurements show that the cavity-lining residues are largely water accessible, consistent with the overall funnel shape of the channel. Our relaxation dispersion data show that residues Val7 and Leu8 near the asparagine ring are subject to large chemical exchange, suggesting significant intrinsic channel breathing at the tip of the funnel. Moreover, the hinge regions connecting the narrow and wide regions of the funnel show strong relaxation dispersion and these regions are the binding sites for rimantadine. Presence of rimantadine decreases the conformational dynamics near the asparagine ring and the hinge area. Our data provide direct observation of μs–ms dynamics of the p7 channel and support the molecular wedge mechanism of rimantadine inhibition of the HCV p7 channel.

  6. No midterm advantages in the middle term using small intestinal submucosa and human amniotic membrane in Achilles tendon transverse tenotomy.

    Science.gov (United States)

    Liu, Yushu; Peng, Yinbo; Fang, Yong; Yao, Min; Redmond, Robert W; Ni, Tao

    2016-11-24

    The study was aimed to compare the effects of small intestinal submucosa (SIS) and human amniotic membrane (HAM) on Achilles tendon healing. A total of 48 New Zealand white rabbits were divided into two groups. A full-thickness transverse tenotomy was made at the right leg of the rabbits. Then, the laceration site was wrapped with HAM (P/A group) or SIS (P/S group). The ultimate stress (US) and Young's modulus (E) of the tendons were detected for biomechanical analysis. Histological evaluation was performed using hematoxylin and eosin, immunohistochemical, and immunofluorescent stain. Expression of collagen I was detected by western blot analysis, and levels of inflammatory cytokines IL-1β, IL-6, and TNF-α were measured. Finally, adhesion formation was evaluated. There were no significant differences in filamentous adhesion, cross-sectional areas of the laceration sites, levels of inflammatory response, and collagen type I expression between the P/A and P/S groups (p > 0.05). Compared with the P/A group, the US and E values were significantly higher in the P/S group at day 7 (p Achilles tendon injury in the early stage of healing.

  7. A randomised cross-over comparison of the transverse and longitudinal techniques for ultrasound-guided identification of the cricothyroid membrane in morbidly obese subjects

    DEFF Research Database (Denmark)

    Kristensen, M S; Teoh, W H; Rudolph, S S

    2016-01-01

    -on training, and then applied both techniques in a randomised, cross-over sequence to obese females with body mass index 39.0 - 43.9 kg.m(-2) . The mean (SD) time to identify the cricothyroid membrane was 24.0 (12.4) s using the transverse technique compared with 37.6 (17.9) s for the longitudinal technique...

  8. Platinum-modified SiO{sub 2} with tubular morphology as efficient membrane-type microreactors for mineralization of formic acid

    Energy Technology Data Exchange (ETDEWEB)

    Anastasescu, Crina; Anastasescu, Mihai; Zaharescu, Maria; Balint, Ioan, E-mail: ibalint@icf.ro [Romanian Academy, Institute of Physical Chemistry (Romania)

    2012-10-15

    SiO{sub 2} amorphous tubes with the internal diameter ranging between 5 and 170 nm and having the aspect ratios typically >50, were prepared using DL-tartaric acid as inorganic template. The tubular SiO{sub 2} was impregnated with a platinum precursor (H{sub 2}PtCl{sub 6}), dried and then reduced with H{sub 2}. The TEM, XPS, FTIR characterization methods revealed that platinum species were located preferentially on the inner walls of tubes having diameter smaller than 100 nm. The walls of SiO{sub 2} nanotubes proved to be amorphous and highly porous, the diameter of pores covering a wide range of radii. The macroporosity of the SiO{sub 2} tubes originated from the open ends of the tubes with the diameter {>=}100 nm, whereas the pores located in the walls of tubes were responsible for the meso and microporosity. Finer Pt nanoparticles (0.9 nm average size) were obtained after the catalyst was dried in air in mild conditions compared to the catalytic material reduced with H{sub 2} (5.3 nm mean size) According to FTIR results, strong metal-support interaction was evidenced between platinum nanoparticles and inner walls of SiO{sub 2} nanotubes. In order to observe the effect of Pt nanoparticle morphology on catalytic behavior, the activity of platinum-modified SiO{sub 2} tubes (1 wt% Pt/SiO{sub 2}) for the oxidation of formic acid to CO{sub 2} was investigated in the 20-75 Degree-Sign C temperature range. The catalytic activity-morphology relationship of Pt/SiO{sub 2} nanotubes was studied and the results were explained in light of experimental results. The catalytic experiments revealed for the first time that SiO{sub 2} nanotubes with highly permeable walls behave as efficient membrane-type microreactors for the oxidation of formic acid to CO{sub 2}. This type of morphological-dependent catalysis may prove to be an efficient tool in near future for the abatement of pollutants in liquid phase.

  9. Evaluation of clayey masses compositions starting from the residue incorporation of the red ceramic industry to obtain tubular ceramic membranes; Avaliacao das composicoes de massas argilosas a partir da incorporacao de residuo da industria de ceramica vermelha na obtencao de membranas ceramicas tubulares

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Adriano Lima da; Chaves, Alexsandra Cristina; Luna, Carlos Bruno Barreto; Neves, Gelmires de Araujo; Lira, Helio de Lucena, E-mail: adrianolimadasilva@hotmail.com, E-mail: alexsandra.chaves@ifap.edu.br, E-mail: brunobarretodemaufcg@hotmail.com, E-mail: gelmires@ufcg.edu.br, E-mail: helio@ufcg.edu.br [Universidade Federal de Campina Grande (UAEMa/CCT/UFCG), PB (Brazil). Unidade Academica de Engenharia de Materiais

    2017-01-15

    The inappropriate residue disposal of red ceramic industry is very high. Nowadays, one of the major challenges is the investigation of processes to obtain alternative materials, enabling the use of these residues to manufacture new materials. This work's objective is to study clayey masses' compositions starting from the residue incorporation of the red ceramic industry to be used in tubular ceramic membranes. Two compositions of ceramic masses were established, composition A (50% of residue) and composition B (70% of residue). Granulometric analysis of the ceramic masses presented an average size of particles, what indicates membranes in the microfiltration scale. Another observed factor is related to the increase of residue amount, what favored a decrease in the ceramic mass' plasticity. A rise in the apparent porosity was also observed, probably because of a possible growing in the bigger pores numbers, due to the sintering high temperature and the elevation of residue quantity itself. (author)

  10. Tubular bioreactor and its application; Tubular bioreactor to sono tekiyo

    Energy Technology Data Exchange (ETDEWEB)

    Endo, I.; Nagamune, T. [The University of Tokyo, Tokyo (Japan). Faculty of Engineering; Yuki, K. [Nikka Whisky Distilling Co. Ltd. Tokyo (Japan); Inaba, H. [Sumitomo Heavy Industries, Ltd., Tokyo (Japan)

    1994-09-05

    The loop type tubular bioreactor (TBR) was developed where biocatalysts are trapped in the reactor by membrane module. A UF membrane or MF membrane and crossflow filtration were adopted for the membrane module, and the reactor loop was composed of four membrane modules. The reactor was operated at 2-4 m/s in membrane surface velocity and 300-400 kPa in filtration pressure. As the result of the high-density culture of lactic acid bacteria and yeast, a biomass concentration was more than 10 times that in batch culture, suggesting the remarkable enhancement of a production efficiency. As the result of the continuous fermentation of cider, the fast fermentation more than 60 times that in conventional ones was obtained together with the same quality as conventional ones. Such a fast fermentation was probably achieved by yeast suspended in the fermenter of TBR, by yeast hardly affected physico-chemically as compared with immobilized reactors, and by small effect of mass transfer on reaction systems. 4 refs., 6 figs.

  11. Stem Cell Factor Expression after Renal Ischemia Promotes Tubular Epithelial Survival

    NARCIS (Netherlands)

    Stokman, Geurt; Stroo, Ingrid; Claessen, Nike; Teske, Gwendoline J. D.; Weening, Jan J.; Leemans, Jaklien C.; Florquin, Sandrine

    2010-01-01

    Background: Renal ischemia leads to apoptosis of tubular epithelial cells and results in decreased renal function. Tissue repair involves re-epithelialization of the tubular basement membrane. Survival of the tubular epithelium following ischemia is therefore important in the successful regeneration

  12. Ultrafiltration performance of tubular membrane modules fitted with turbulent promoter. Twisted tape and static mixer; Ranryu sokushintai wo sobishita kangata gengai roka tokusei. Twist tape to static mixer

    Energy Technology Data Exchange (ETDEWEB)

    Sugimoto, T.; Kobayashi, H.; Ishikawa, T.; Kamiya, T. [Kogakuin University, Tokyo (Japan); Niitsu, T.; Inoue, H. [Soka University, Tokyo (Japan)

    1996-01-20

    The permeate flux of a membrane module fitted with a twisted tape or static mixer was 4-7.7 times higher than that of a membrane module without any turbulent promoter. Use of a twisted tape or static mixer shortened separation time. The energy consumption per unit mass of permeate due to pressure drop in the membrane module with twisted tape or static mixer was 2-3 times higher than that in the membrane module without turbulent promoter. The permeate flux solved by introducing the value of mass transfer coefficient into the osmotic pressure model coincided well with experimental results, where the mass transfer coefficient was obtained by simulating experimental formula of heat transfer in a pipe fitted with a twisted tape or static mixer into a mass transfer correlation by the heat transfer-mass transfer analogy. The mass transfer coefficient in a membrane module with twisted tape or static mixer increased to about 4 to 8 times that of a membrane module without turbulent promoter. 7 refs., 10 figs.

  13. Proximal renal tubular acidosis

    Science.gov (United States)

    ... glands that produce tears and saliva are destroyed Wilson disease , an inherited disorder in which there is too much copper in the body's tissues Vitamin D deficiency Symptoms Symptoms of proximal renal tubular acidosis include any ...

  14. Motor neuron disease-associated mutant vesicle-associated membrane protein-associated protein (VAP) B recruits wild-type VAPs into endoplasmic reticulum-derived tubular aggregates

    NARCIS (Netherlands)

    Teuling, Eva; Ahmed, Suaad; Haasdijk, Elize; Demmers, Jeroen; Steinmetz, Michel O; Akhmanova, Anna; Jaarsma, Dick; Hoogenraad, Casper C

    2007-01-01

    The vesicle-associated membrane protein-associated proteins (VAPs) VAPA and VAPB interact with lipid-binding proteins carrying a short motif containing two phenylalanines in an acidic tract (FFAT motif) and targets them to the cytosolic surface of the endoplasmic reticulum (ER). A genetic mutation

  15. Anatomical distribution of voltage-dependent membrane capacitance in frog skeletal muscle fibers.

    Science.gov (United States)

    Huang, C L; Peachey, L D

    1989-03-01

    Components of nonlinear capacitance, or charge movement, were localized in the membranes of frog skeletal muscle fibers by studying the effect of 'detubulation' resulting from sudden withdrawal of glycerol from a glycerol-hypertonic solution in which the muscles had been immersed. Linear capacitance was evaluated from the integral of the transient current elicited by imposed voltage clamp steps near the holding potential using bathing solutions that minimized tubular voltage attenuation. The dependence of linear membrane capacitance on fiber diameter in intact fibers was consistent with surface and tubular capacitances and a term attributable to the capacitance of the fiber end. A reduction in this dependence in detubulated fibers suggested that sudden glycerol withdrawal isolated between 75 and 100% of the transverse tubules from the fiber surface. Glycerol withdrawal in two stages did not cause appreciable detubulation. Such glycerol-treated but not detubulated fibers were used as controls. Detubulation reduced delayed (q gamma) charging currents to an extent not explicable simply in terms of tubular conduction delays. Nonlinear membrane capacitance measured at different voltages was expressed normalized to accessible linear fiber membrane capacitance. In control fibers it was strongly voltage dependent. Both the magnitude and steepness of the function were markedly reduced by adding tetracaine, which removed a component in agreement with earlier reports for q gamma charge. In contrast, detubulated fibers had nonlinear capacitances resembling those of q beta charge, and were not affected by adding tetracaine. These findings are discussed in terms of a preferential localization of tetracaine-sensitive (q gamma) charge in transverse tubule membrane, in contrast to a more even distribution of the tetracaine-resistant (q beta) charge in both transverse tubule and surface membranes. These results suggest that q beta and q gamma are due to different molecules and that

  16. Separation of BSA through FAU-type zeolite ceramic composite membrane formed on tubular ceramic support: Optimization of process parameters by hybrid response surface methodology and biobjective genetic algorithm.

    Science.gov (United States)

    Vinoth Kumar, R; Ganesh Moorthy, I; Pugazhenthi, G

    2017-08-09

    In this study, Faujasite (FAU) zeolite was coated on low-cost tubular ceramic support as a separating layer through hydrothermal route. The mixture of silicate and aluminate solutions was used to create a zeolitic separation layer on the support. The prepared zeolite ceramic composite membrane was characterized using X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), particle size distribution (PSD), field emission scanning electron microscopy (FESEM), and zeta potential measurements. The porosity of ceramic support (53%) was reduced by the deposition of FAU (43%) zeolite layer. The pore size and water permeability of the membrane were evaluated as 0.179 µm and 1.62 × 10 -7  m 3 /m 2  s kPa, respectively, which are lower than that of the support (pore size of 0.309 µm and water permeability of 5.93 × 10 -7  m 3 /m 2  s kPa). The permeate flux and rejection potential of the prepared membrane were evaluated by microfiltration of bovine serum albumin (BSA). To study the influences of three independent variables such as operating pressure (68.94-275.79 kPa), concentration of BSA (100-500 ppm), and solution pH (2-4) on permeate flux and percentage of rejection, the response surface methodology (RSM) was used. The predicted models for permeate flux and rejection were further subjected to biobjective genetic algorithm (GA). The hybrid RSM-GA approach resulted in a maximum permeate flux of 2.66 × 10 -5  m 3 /m 2  s and BSA rejection of 88.02%, at which the optimum conditions were attained as 100 ppm BSA concentration, 2 pH solution, and 275.79 kPa applied pressure. In addition, the separation efficiency was compared with other membranes applied for BSA separation to know the potential of the fabricated FAU zeolite ceramic composite membrane.

  17. Modeling constrained sintering of bi-layered tubular structures

    DEFF Research Database (Denmark)

    Tadesse Molla, Tesfaye; Kothanda Ramachandran, Dhavanesan; Ni, De Wei

    2015-01-01

    Constrained sintering of tubular bi-layered structures is being used in the development of various technologies. Densification mismatch between the layers making the tubular bi-layer can generate stresses, which may create processing defects. An analytical model is presented to describe...... the densification and stress developments during sintering of tubular bi-layered samples. The correspondence between linear elastic and linear viscous theories is used as a basis for derivation of the model. The developed model is first verified by finite element simulation for sintering of tubular bi-layer system....... Furthermore, the model is validated using densification results from sintering of bi-layered tubular ceramic oxygen membrane based on porous MgO and Ce0.9Gd0.1O1.95-d layers. Model input parameters, such as the shrinkage kinetics and viscous parameters are obtained experimentally using optical dilatometry...

  18. Renal tubular acidosis.

    Science.gov (United States)

    Santos, Fernando; Gil-Peña, Helena; Alvarez-Alvarez, Silvia

    2017-04-01

    To facilitate the understanding and knowledge of renal tubular acidosis by providing a summarized information on the known clinical and biochemical characteristics of this group of diseases, by updating the genetic and molecular bases of the primary forms renal tubular acidosis and by examining some issues regarding the diagnosis of distal renal tubular acidosis (RTA) in the daily clinical practice. The manuscript presents recent findings on the potential of next-generation sequencing to disclose new pathogenic variants in patients with a clinical diagnosis of primary RTA and negative Sanger sequencing of known genes. The current review emphasizes the importance of measuring urinary ammonium for a correct clinical approach to the patients with metabolic acidosis and discusses the diagnosis of incomplete distal RTA. We briefly update the current information on RTA, put forward the need of additional studies in children to validate urinary indexes used in the diagnosis of RTA and offer a perspective on diagnostic genetic tests.

  19. Método de impregnação química aplicado em tubos microporosos e membranas tubulares para a microfiltração de emulsões e suspensões de bactérias Method of chemical impregnation applied to microporous tubes and tubular membranes for the microfiltration of emulsions and bacteria suspensions

    Directory of Open Access Journals (Sweden)

    R. Del Colle

    2008-03-01

    Full Text Available Uma técnica de impregnação química via solução de precursor foi desenvolvida para formação de filmes finos em tubos microporosos e membranas tubulares. O desempenho desta técnica foi analisado no processo de microfiltração de emulsões (óleo vegetal/água e de suspensões de bactérias (Escherichia coli do soro residual do processamento de queijo. Os tubos microporosos (tamanho nominal 0,5 µm foram impregnados com solução precursora de zircônia (e calcinados a 600 e 900 ºC afim de influenciar na melhora do processo de desemulsificação e as membranas cerâmicas (tamanho nominal entre 0,8 µm e 1,2 µm foram impregnadas com precursor (e calcinadas a 600 °C para formação de prata metálica, para agir como bactericida na suspensão residuária de bactérias da indústria de queijo. O meio poroso impregnado foi caracterizado por meio de microscopia eletrônica de varredura. Os resultados da análise do permeado para valores do teor orgânico de carbono são respectivos ao tratamento de emulsões; o valor da contagem de bactérias via análise de plaqueamento é respectivo ao tratamento de suspensão de bactérias. Os resultados foram analisados e discutidos em função do desempenho e da influência da impregnação quanto à presença de zircônia ou prata para cada aplicação.A technique of chemical impregnation by precursor solution was developed for the formation of thin films in microporous tubes and tubular membranes. The performance of this technique was analyzed by the microfiltration process of emulsions (vegetable oil/water and bacteria suspensions (Escherichia coli of the whey of milk of cheese processing. The microporous tubes (nominal pore size 0.5 µm were impregnated with a precursor zirconia solution and calcined at 600 and 900 ºC to influence the improvement of the demulsification process. Ceramic membranes (nominal pore size between 0.8 µm and 1.2 µm were impregnated with a silver precursor and calcined at

  20. Distal renal tubular acidosis

    Science.gov (United States)

    ... the body's immune system mistakenly attacks healthy tissue Wilson disease , an inherited disorder in which there is too much copper in the body's tissues Use of certain medicines, such as amphotericin B, lithium, and analgesics Symptoms Symptoms of distal renal tubular acidosis include any ...

  1. Reliability of Tubular Joints

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Thoft-Christensen, Palle

    In this paper the preliminary results obtained by tests on tubular joints are presented. The joints are T-joints and the loading is static. It is the intention in continuation of these tests to perform tests on other types of joints (e.g. Y-joints) and also with dynamic loading. The purpose of th...

  2. Operational characteristics and power scaling of a transverse flow ...

    Indian Academy of Sciences (India)

    Abstract. Transverse flow transversely excited (TFTE) CO2 lasers are easily scalable to multi- kilowatt level. The laser power can be scaled up by increasing the volumetric gas flow and discharge volume. It was observed in a TFTE CW CO2 laser having single row of pins as an anode and tubular cathode that the laser ...

  3. Transversity 2005

    Science.gov (United States)

    Barone, Vincenzo; Ratcliffe, Philip G.

    Introduction. Purpose and status of the Italian Transversity Project / F. Bradamante -- Opening lecture. Transversity / M. Anselmino -- Experimental lectures. Azimuthal single-spin asymmetries from polarized and unpolarized hydrogen targets at HERMES / G. Schnell (for the HERMES Collaboration). Collins and Sivers asymmetries on the deuteron from COMPASS data / I. Horn (for the COMPASS Collaboration). First measurement of interference fragmentation on a transversely polarized hydrogen target / P. B. van der Nat (for the HERMES Collaboration). Two-hadron asymmetries at the COMPASS experiment / A. Mielech (for the COMPASS Collaboration). Measurements of chiral-odd fragmentation functions at Belle / R. Seidl ... [et al.]. Lambda asymmetries / A. Ferrero (for the COMPASS Collaboration). Transverse spin at PHENIX: results and prospects / C. Aidala (for the PHENIX Collaboration). Transverse spin and RHIC / L. Bland. Studies of transverse spin effects at JLab / H. Avakian ... [et al.] (for the CLAS Collaboration). Neutron transversity at Jefferson Lab / J. P. Chen ... [et al.] (for the Jefferson Lab Hall A Collaboration). PAX: polarized antiproton experiments / M. Contalbrigo. Single and double spin N-N interactions at GSI / M. Maggiora (for the ASSIA Collaboration). Spin filtering in storage rings / N. N. Nikolaev & F. F. Pavlov -- Theory lectures. Single-spin asymmetries and transversity in QCD / S. J. Brodsky. The relativistic hydrogen atom: a theoretical laboratory for structure functions / X. Artru & K. Benhizia. GPD's and SSA's / M. Burkardt. Time reversal odd distribution functions in chiral models / A. Drago. Soffer bound and transverse spin densities from lattice QCD / M. Diehl ... [et al.]. Single-spin asymmetries and Qiu-Sterman effect(s) / A. Bacchetta. Sivers function: SIDIS data, fits and predictions / M. Anselmino ... [et al.]. Twist-3 effects in semi-inclusive deep inelastic scattering / M. Schlegel, K. Goeke & A. Metz. Quark and gluon Sivers functions / I

  4. [Transversal problems].

    Science.gov (United States)

    Mendoza Mendoza, A; Solano Reina, E

    1990-04-01

    In this worn we introduce the alterations of the occlusion in the horizontal level or transversal problems, in which lateral crossed bites appear, either with or without a deviation of the medium line, underlying its differential diagnostic and guide lines treatment through several different clinic cases.

  5. Transverse myelitis

    International Nuclear Information System (INIS)

    Black, M.J.; Motaghedi, B.; Robitaille, Y.

    1980-01-01

    Transverse myelitis is a known complication of radiation treatment for carcinoma of the heat and neck. In a five year period, 1970 to 1975, 120 patients with head and neck cancer received radiation as part of their treatment in this hospital. A review of the records of these patients showed only two cases of myelitis, an incidence of about 2%. This paper reviews the clinical syndrome; treatment and preventive measures are discussed and a survey of the literature is presented

  6. Tubular closure mechanism

    International Nuclear Information System (INIS)

    Kalen, D.D.; Mitchem, J.W.

    1981-01-01

    An apparatus is provided for closing the bore of a tube and releasably securing articles within the tube under longitudinal load. A latching member has a cylindrical section and several circumferentially-spaced elongated latches hanging down from one end of the cylinder. An elongated actuator has integral cam and spline and is partly located within the latch with the cam radially contacting the latches and the spline projecting into the circumferential spaces between the latches. The actuator is axially movable between a position in which the latches are locked to the tube walls and a position in which the latches are secured from contact with the tube walls. Means are provided for axially moving the actuator such that the cam positions the latches; and means are also provided for engaging the articles within the tube. The closure is particularly applicable to tubular irradiation surveillance specimen assembly holders used in reactors

  7. The influence of three barrier membranes on modeling and incorporation of autologous onlay bone grafts in rats. An evaluation by transversal microradiography

    NARCIS (Netherlands)

    Gielkens, Pepijn F. M.; Hoogeveen, Eelke J.; Schortinghuis, Jurjen; Ruben, Jan L.; Huysmans, Marie-Charlotte D. N. J. M.; Stegenga, Boudewijn

    Objectives: To determine whether covering an autologous bone grafts with three different barrier membranes prevents graft resorption, and to compare these membranes to each other. Design: In 192 rats a standardised 4.0 mm diameter bone graft was harvested from the right mandibular angle and

  8. Transverse feedback

    CERN Document Server

    Cornelis, K; Sladen, Jonathan P H; CERN. Geneva. SPS and LEP Division

    1997-01-01

    The aim of these MD's was to set up the transverse feedback for damping in both planes, and to test the charge normalization and gain compensation. The latter is intended to reduce the gain of the feedback for small oscillations in order to improve compatibility with the Q loop. All work was done with 2 x 4 bunches, family A. In the first two MD's the feedback was set up for damping in both planes with charge normalization. In the third, gain compensation was commissioned in the vertical plane with Qv' set to -2. It was found either to increase the level of the m = 0 mode or to leave it unchanged. Under these conditions 6mA total current was accumulated.

  9. Transverse damper

    CERN Document Server

    Höfle, W

    2012-01-01

    Plans for the operation of the transverse damper in 2012 at bunch spacings of 50 ns and 25 ns and at increased collision energy will be reviewed. The increased energy and the experience that will be gained at 25 ns are very important to define any upgrades that may be necessary for the high luminosity operation at 7 TeV after LS1. This means that the available parameter space must be probed in 2012 which in particular includes a higher feedback gain in the ramp and with colliding beams. Limits for the feedback gain for the current system will be outlined. The potential benefits of running with higher feedback gain for a better emittance preservation will be stressed and weighed against the operational difficulties and the potential impact of noise in the damper system. A plan for re-commissiong at 50 ns and 25 ns for operation at 4 TeV will be outlined.

  10. Stem cell factor expression after renal ischemia promotes tubular epithelial survival.

    Directory of Open Access Journals (Sweden)

    Geurt Stokman

    Full Text Available BACKGROUND: Renal ischemia leads to apoptosis of tubular epithelial cells and results in decreased renal function. Tissue repair involves re-epithelialization of the tubular basement membrane. Survival of the tubular epithelium following ischemia is therefore important in the successful regeneration of renal tissue. The cytokine stem cell factor (SCF has been shown to protect the tubular epithelium against apoptosis. METHODOLOGY/PRINCIPAL FINDINGS: In a mouse model for renal ischemia/reperfusion injury, we studied how expression of c-KIT on tubular epithelium and its ligand SCF protect cells against apoptosis. Administration of SCF specific antisense oligonucleotides significantly decreased specific staining of SCF following ischemia. Reduced SCF expression resulted in impaired renal function, increased tubular damage and increased tubular epithelial apoptosis, independent of inflammation. In an in vitro hypoxia model, stimulation of tubular epithelial cells with SCF activated survival signaling and decreased apoptosis. CONCLUSIONS/SIGNIFICANCE: Our data indicate an important role for c-KIT and SCF in mediating tubular epithelial cell survival via an autocrine pathway.

  11. Mathematical rationalization for the renal tubular transport: revised concepts.

    Science.gov (United States)

    Mioni, Roberto; Marega, Alessandra; Romano, Giulio; Montanaro, Domenico

    2017-09-01

    The current emphasis on kinetics and in situ control of molecular exchanges, across the tubular membrane, has not been paralleled by corresponding improvements in our understanding of tubular behaviour at the macroscopic level of classical physiology. In this paper, we propose a mathematical rationalization of macroscopic tubular transport by means of a principal transport equation, originating from the law of mass action between substrate and carrier. The other equations, derived from the main one, demonstrate the possibility of distinguishing between transporters with low affinity and high capacity and transporters with high affinity and low capacity. Moreover, our model formalizes both tubular reabsorption and tubular secretion. Regarding the renal calcium handling, our model confirms the two-compartment system proposed by Mioni in 1971, with some important variants, which are in agreement with the fractional reabsorptions of this cation along the tubule, as verified by micro-puncture technique. To obtain the frequency distribution of saturated tubules, we have utilized the infinitesimal analysis method, starting from the equations proposed by Smith in 1943, concluding that all titration curves result from the combined effect of enzymatic approach and anatomical heterogeneity of the nephrons. The theoretical equations included in our manuscript reflect substantial and palpable physiological mechanisms able to suggest diagnosis and therapy of some electrolyte and hormonal disorders. At the end of this paper, we highlight advantages and disadvantages detectable by comparing our mathematical approach with Marshall's and Bijvoet's methods, proposed, respectively, in 1976 and 1984.

  12. Renal tubular vasopressin receptors downregulated by dehydration

    International Nuclear Information System (INIS)

    Steiner, M.; Phillips, M.I.

    1988-01-01

    Receptors for arginine vasopressin (AVP) were characterized in tubular epithelial basolateral membranes (BL membranes) prepared from the kidneys of male Spraque-Dawley rats. Association of [ 3 H]AVP was rapid, reversible, and specific. Saturation studies revealed a single class of saturable binding sites with a maximal binding (B max ) of 184 ± 15 fmol/mg protein. The V 2 receptor antagonist was more than 3,700 times as effective in displacing [ 3 H]AVP than was the V 1 antagonist. To investigate the physiological regulation of vasopressin receptors, the effects of elevated levels of circulating AVP on receptor characteristics were studied. Seventy-two-hour water deprivation significantly elevated plasma osmolality and caused an 11.5-fold increase in plasma [AVP]. Scatchard analysis revealed a 38% decreased in the number of AVP receptors on the BL membranes from dehydrated animals. The high-affinity binding sites on the BL membranes fit the pharmacological profile for adenylate cyclase-linked vasopressin receptors (V 2 ), which mediate the antidiuretic action of the hormone. The authors conclude that physiologically elevated levels of AVP can downregulate vasopressin receptors in the kidney

  13. Tubular lysosome morphology and distribution within macrophages depend on the integrity of cytoplasmic microtubules

    International Nuclear Information System (INIS)

    Swanson, J.; Bushnell, A.; Silverstein, S.C.

    1987-01-01

    Pinocytosis of the fluorescent dye lucifer yellow labels elongated, membrane-bound tubular organelles in several cell types, including cultured human monocytes, thioglycolate-elicited mouse peritoneal macrophages, and the macrophage-like cell line J774.2. These tubular structures can be identified as lysosomes by acid phosphatase histochemistry and immunofluorescence localization of cathepsin L. The abundance of tubular lysosomes is markedly increased by treatment with phorbol 12-myristate 13-acetate. When labeled by pinocytosis of microperoxidase and examined by electron microscopic histochemistry, the tubular lysosomes have an outside diameter of ≅ 75 nm and a length of several micrometers; they radiate from the cell's centrosphere in alignment with cytoplasmic microtubules and intermediate filaments. Incubation of phorbol myristate acetate-treated macrophages at 4 0 C or in medium containing 5 μM colchicine or nocodazole at 37 0 C leads to disassembly of microtubules and fragmentation of the tubular lysosomes. Return of the cultures to 37 0 C or removal of nocodazole from the medium leads to reassembly of microtubules and the reappearance of tubular lysosomes within 10-20 min. The authors conclude that microtubules are essential for the maintenance of tubular lysosome morphology and that, in macrophages, a significant proportion of the lysosomal compartment is contained within these tubular structures

  14. Template Synthesis of Tubular Nanostructures for Loading Biologically Active Molecules.

    Science.gov (United States)

    Karatas, Aysegul; Algan, Aslıhan Hilal

    2017-01-01

    The template synthesis is a low cost, simple and versatile nanofabrication method to produce cylindrical/tubular nanostructures with controllable dimensions such as length, diameter and aspect ratio. This method utilizes nanoporous membranes such as anodized aluminum oxide (AAO) or polycarbonate (PC) as templates which have nanosized specific, cylindrical and uniform inner pores to be coated with the desired material. Template synthesized nanotubular structures have been produced from variety of materials including ceramics, polymers and proteins for loading biologically active molecules. Available procedures of material deposition into the template nanopores consist of several techniques like wetting (melt or solution wetting), layer-by-layer (LbL) assembly and sol-gel chemistry. Template synthesis enables not only control of the geometry of the resulting nanostructures but also provides nanovehicles having separated inner and outer surfaces which can be variously functionalized. Tubular nanostructures fabricated by this method have numerous potential applications including delivery of biologically active molecules such as drugs, gene, enzymes and proteins. In this review we aimed to present up-to-date works on the template based synthesis which has greatly facilitated the fabrication of polymer and protein tubular nanostructures, principally. The strategies regarding the synthesis and designing of these promising tubular nanostructures together with recent approaches relevant of drug delivery was also presented. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  15. Tubular Initial Conditions and Ridge Formation

    Directory of Open Access Journals (Sweden)

    M. S. Borysova

    2013-01-01

    Full Text Available The 2D azimuth and rapidity structure of the two-particle correlations in relativistic A+A collisions is altered significantly by the presence of sharp inhomogeneities in superdense matter formed in such processes. The causality constraints enforce one to associate the long-range longitudinal correlations observed in a narrow angular interval, the so-called (soft ridge, with peculiarities of the initial conditions of collision process. This study's objective is to analyze whether multiform initial tubular structures, undergoing the subsequent hydrodynamic evolution and gradual decoupling, can form the soft ridges. Motivated by the flux-tube scenarios, the initial energy density distribution contains the different numbers of high density tube-like boost-invariant inclusions that form a bumpy structure in the transverse plane. The influence of various structures of such initial conditions in the most central A+A events on the collective evolution of matter, resulting spectra, angular particle correlations and vn-coefficients is studied in the framework of the hydrokinetic model (HKM.

  16. A Tubular Biomaterial Construct Exhibiting a Negative Poisson's Ratio.

    Directory of Open Access Journals (Sweden)

    Jin Woo Lee

    Full Text Available Developing functional small-diameter vascular grafts is an important objective in tissue engineering research. In this study, we address the problem of compliance mismatch by designing and developing a 3D tubular construct that has a negative Poisson's ratio νxy (NPR. NPR constructs have the unique ability to expand transversely when pulled axially, thereby resulting in a highly-compliant tubular construct. In this work, we used projection stereolithography to 3D-print a planar NPR sheet composed of photosensitive poly(ethylene glycol diacrylate biomaterial. We used a step-lithography exposure and a stitch process to scale up the projection printing process, and used the cut-missing rib unit design to develop a centimeter-scale NPR sheet, which was rolled up to form a tubular construct. The constructs had Poisson's ratios of -0.6 ≤ νxy ≤ -0.1. The NPR construct also supports higher cellular adhesion than does the construct that has positive νxy. Our NPR design offers a significant advance in the development of highly-compliant vascular grafts.

  17. Miopatias associadas a agregados tubulares

    Directory of Open Access Journals (Sweden)

    Mary Souza Carvalho

    1993-09-01

    Full Text Available Os autores relatam a caso de paciente de 58 anos de idade do sexo masculino, com quadro de características miastênicas tanto clínica como eletromiograficamente, no qual a biópsia muscular com histoquímica e microscopia eletrônica permitiu fazer o diagnostico de miopatia associada a agregados tubulares. É chamada a atenção para o fato de que as alterações anátomo-patológicas encontradas podem estar presentes em um grupo heterogêneo de pacientes com grande variedade de sintomas, não havendo portanto motivo para considerar-se a existência de uma miopatia com agregados tubulares, já que os achados anátomo-patológicos são inespecíficos e não configuram moléstia específica.

  18. Excitability of the T-tubular system in rat skeletal muscle

    DEFF Research Database (Denmark)

    Nielsen, O B; Ørtenblad, Niels; Lamb, G D

    2004-01-01

    (+) pumps. The exercise-induced build-up of extracellular K(+) is most likely larger in the T-tubules than in the interstitium but the significance of the cation shifts and Na(+)-K(+) pump for the excitability of the T-tubular membrane and the voltage sensors is largely unknown. Using mechanically skinned...... fibres, we here study the role of the Na(+)-K(+) pump in maintaining T-tubular function in fibres with reduced chemical K(+) gradient. The Na(+)-K(+) pump activity was manipulated by changing [Na(+)](i). The responsiveness of the T-tubules was evaluated from the excitation-induced force production...... frequency stimulation. It is concluded that a reduction in the chemical gradient for K(+), as takes place during intensive exercise, may depress T-tubular function, but that a concomitant exercise-induced increase in [Na(+)](i) protects T-tubular function by stimulating the Na(+)-K(+) pump....

  19. Tumor-promoting phorbol esters effect alkalinization of canine renal proximal tubular cells

    Energy Technology Data Exchange (ETDEWEB)

    Mellas, J.; Hammerman, M.R.

    1986-03-01

    We have demonstrated the presence of specific receptors for tumor-promoting phorbol esters in the plasma membrane of the canine renal proximal tubular cell. These compounds affect proximal tubular metabolism in vitro. For example, we have shown that they inhibit gluconeogenesis in canine renal proximal tubular segments. Tumor-promoting phorbol esters have been shown to effect alkalinization of non-renal cells, by enhancing Na/sup +/-H/sup +/ exchange across the plasma membrane. To determine whether the actions of tumor-promoting phorbol esters in proximal tubular segments might be mediated by a similar process, we incubated suspensions of segments from dog kidney with these compounds and measured changes in intracellular pH using (/sup 14/C)-5,5-dimethoxazoladine-2-4-dione (DMO) and flow dialysis. Incubation of segments with phorbol 12,13 dibutyrate, but not inactive phorbol ester, 4 ..gamma.. phorbol, effected alkalinization of cells within the segments in a concentration-dependent manner. Alkalinization was dependent upon the presence of extracellular (Na/sup +/) > intracellular (Na/sup +/), was prevented by amiloride and was demonstrable in the presence of SITS. Our findings suggest that tumor-promoting esters stimulate the Na/sup +/-H/sup +/ exchanger known to be present in the brush border membrane of the renal proximal tubular cell. It is possible that the stimulation reflects a mechanism by which phorbol esters affect metabolic processes in these cells.

  20. A model of the guinea-pig ventricular cardiac myocyte incorporating a transverse–axial tubular system

    Czech Academy of Sciences Publication Activity Database

    Pásek, Michal; Šimurda, J.; Orchard, C.; Christé, G.

    2008-01-01

    Roč. 96, 1-3 (2008), s. 258-280 ISSN 0079-6107 Institutional research plan: CEZ:AV0Z20760514 Keywords : guinea pig * cardiac cell * transverse-axial tubular system * quantitative model Subject RIV: BO - Biophysics Impact factor: 6.388, year: 2008

  1. Modified tubularized incised plate urethroplasty

    Directory of Open Access Journals (Sweden)

    Shivaji Mane

    2013-01-01

    Full Text Available Aim: To share our experience of doing tubularized incised plate urethroplasty with modifications. Materials and Methods: This is a single surgeon personal series from 2004 to 2009. One hundred patients of distal hypospadias were subjected for Snodgrass urethroplasty with preputioplasty. The age range was 1 to 5 year with mean age of 2.7 years. Selection criteria were good urethral plate, without chordee and torsion needing complete degloving. Main technical modification from original Snodgrass procedure was spongioplasty, preputioplasty, and dorsal slit when inability to retract prepuce during surgery. Results: Average follow-up period is 23 months. Seven (7% patients developed fistula and one patient had complete preputial dehiscence. Phimosis developed in three (3% patients and required circumcision. Dorsal slit was required in seven patients. One patient developed meatal stenosis in postoperative period. All other patients are passing single urinary stream and have cosmesis that is acceptable. Conclusions: Modified tubularized incised plate urethroplasty with preputioplasty effectively gives cosmetically normal looking penis with low complications.

  2. Electricity generation by a novel design tubular plant microbial fuel cell

    NARCIS (Netherlands)

    Timmers, R.A.; Strik, D.P.B.T.B.; Hamelers, H.V.M.; Buisman, C.J.N.

    2013-01-01

    The tubular plant microbial fuel cell was designed to increase the feasibility of this technology. To test the new setup two anode materials were investigated, namely a graphite felt and graphite granules. The average power output based on membrane area was 10 mW m-2 for felt, and 12 mW m-2 for

  3. Tubular lining material for pipelines having bends

    Energy Technology Data Exchange (ETDEWEB)

    Moringa, A.; Sakaguchi, Y.; Hyodo, M.; Yagi, I.

    1987-03-24

    A tubular lining material for pipelines having bends or curved portions comprises a tubular textile jacket made of warps and wefts woven in a tubular form overlaid with a coating of a flexible synthetic resin. It is applicable onto the inner surface of a pipeline having bends or curved portions in such manner that the tubular lining material with a binder onto the inner surface thereof is inserted into the pipeline and allowed to advance within the pipeline, with or without the aid of a leading rope-like elongated element, while turning the tubular lining material inside out under fluid pressure. In this manner the tubular lining material is applied onto the inner surface of the pipeline with the binder being interposed between the pipeline and the tubular lining material. The lining material is characterized in that a part of all of the warps are comprised of an elastic yarn around which, over the full length thereof, a synthetic fiber yarn or yarns have been left-and/or right-handedly coiled. This tubular lining material is particularly suitable for lining a pipeline having an inner diameter of 25-200 mm and a plurality of bends, such as gas service pipelines or house pipelines, without occurrence of wrinkles in the lining material in a bend.

  4. Solar driven membrane pervaporation for desalination processes

    NARCIS (Netherlands)

    Zwijnenberg, Harmen Jan; Koops, G.H.; Wessling, Matthias

    2005-01-01

    We describe details of a solar driven pervaporation process for the production of desalinated water from highly contaminated waters. The membrane material is a polyetheramide-based polymer film of 40 ¿m thickness. This Solar Dew® membrane is used in a tubular configuration in a direct solar membrane

  5. Tubular Unimolecular Transmembrane Channels: Construction Strategy and Transport Activities.

    Science.gov (United States)

    Si, Wen; Xin, Pengyang; Li, Zhan-Ting; Hou, Jun-Li

    2015-06-16

    Lipid bilayer membranes separate living cells from their environment. Membrane proteins are responsible for the processing of ion and molecular inputs and exports, sensing stimuli and signals across the bilayers, which may operate in a channel or carrier mechanism. Inspired by these wide-ranging functions of membrane proteins, chemists have made great efforts in constructing synthetic mimics in order to understand the transport mechanisms, create materials for separation, and develop therapeutic agents. Since the report of an alkylated cyclodextrin for transporting Cu(2+) and Co(2+) by Tabushi and co-workers in 1982, chemists have constructed a variety of artificial transmembrane channels by making use of either the multimolecular self-assembly or unimolecular strategy. In the context of the design of unimolecular channels, important advances have been made, including, among others, the tethering of natural gramicidin A or alamethicin and the modification of various macrocycles such as crown ethers, cyclodextrins, calixarenes, and cucurbiturils. Many of these unimolecular channels exhibit high transport ability for metal ions, particularly K(+) and Na(+). Concerning the development of artificial channels based on macrocyclic frameworks, one straightforward and efficient approach is to introduce discrete chains to reinforce their capability to insert into bilayers. Currently, this approach has found the widest applications in the systems of crown ethers and calixarenes. We envisioned that for macrocycle-based unimolecular channels, control of the arrangement of the appended chains in the upward and/or downward direction would favor the insertion of the molecular systems into bilayers, while the introduction of additional interactions among the chains would further stabilize a tubular conformation. Both factors should be helpful for the formation of new efficient channels. In this Account, we discuss our efforts in designing new unimolecular artificial channels from

  6. Radiologic findings of tubular adenoma of the breast

    International Nuclear Information System (INIS)

    Jeong, Mi Gyoung; Oh, Ki Keun

    1996-01-01

    Tubular adenoma (TA) is known as a rare lesion of the breast which is difficult to diagnosis preoperatively because of its rarity and similarity to fibroadenoma. Hence, our purpose is to suggest the characteristic sonographic features for its correct diagnosis. We retrospectively analyzed the clinical data and mammographic and sonographic findings. of seven patients(mean age, 23) who during the previous five years had presented at our hospital with pathologically-proven tubular adenoma. TA was misdiagnosed as fibroadenoma, since on physical examination of these young females, the lesions presented a palpable, non-tender mass. Mammographically, they showed a well defined mass similar to fibroadenoma. However, sonographic findings were characteristic of TA and compared to fibroadenoma, showed a well demarcated and smooth bordered mass with transverse long axis, posterior enhancement and homogeneous lower internal echogenecity. No case showed lateral wall refractive shadowing. In young females, the clinical and mammographic findings of TA are similar to those of fibroadenoma. However, sonographic findings of TA can, be helpful in the differential diagnosis of this entity and fibroadenoma

  7. Radiologic findings of tubular adenoma of the breast

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Mi Gyoung; Oh, Ki Keun [Yonsei Univ. College of Medicine, Seoul (Korea, Republic of)

    1996-10-01

    Tubular adenoma (TA) is known as a rare lesion of the breast which is difficult to diagnosis preoperatively because of its rarity and similarity to fibroadenoma. Hence, our purpose is to suggest the characteristic sonographic features for its correct diagnosis. We retrospectively analyzed the clinical data and mammographic and sonographic findings. of seven patients(mean age, 23) who during the previous five years had presented at our hospital with pathologically-proven tubular adenoma. TA was misdiagnosed as fibroadenoma, since on physical examination of these young females, the lesions presented a palpable, non-tender mass. Mammographically, they showed a well defined mass similar to fibroadenoma. However, sonographic findings were characteristic of TA and compared to fibroadenoma, showed a well demarcated and smooth bordered mass with transverse long axis, posterior enhancement and homogeneous lower internal echogenecity. No case showed lateral wall refractive shadowing. In young females, the clinical and mammographic findings of TA are similar to those of fibroadenoma. However, sonographic findings of TA can, be helpful in the differential diagnosis of this entity and fibroadenoma.

  8. Strength characterization of tubular ceramic materials by flexure of semi-cylindrical specimens

    DEFF Research Database (Denmark)

    Kwok, Kawai; Kiesel, Lutz; Frandsen, Henrik Lund

    2014-01-01

    Mechanical strength at elevated temperatures and operating atmospheres needs to be characterized during development of tubular ceramic components for advanced energy technologies. Typical procedures are time-consuming because a large number of tests are required for a reliable statistical strength...... characterization and every specimen has to be subjected to the process conditions individually. This paper presents an efficient strength characterization methodology for tubular ceramics. The methodology employs flexure of semi-cylindrical specimens as the strength test and implements the tests within a facility...... conducted on oxygen transport membrane materials at room temperature and 850°C....

  9. Transversely Compressed Bonded Joints

    DEFF Research Database (Denmark)

    Hansen, Christian Skodborg; Schmidt, Jacob Wittrup; Stang, Henrik

    2012-01-01

    The load capacity of bonded joints can be increased if transverse pressure is applied at the interface. The transverse pressure is assumed to introduce a Coulomb-friction contribution to the cohesive law for the interface. Response and load capacity for a bonded single-lap joint was derived using...... non-linear fracture mechanics. The results indicated a good correlation between theory and tests. Furthermore, the model is suggested as theoretical base for determining load capacity of bonded anchorages with transverse pressure, in externally reinforced concrete structures....

  10. Diagnosis and treatment of acute tubular necrosis.

    Science.gov (United States)

    Esson, Matthew L; Schrier, Robert W

    2002-11-05

    Acute tubular necrosis (ATN) is common in hospitalized patients, particularly in the intensive care unit. Over the past four decades, the mortality rate from ATN has remained at 50% to 80%. To review recent studies of diagnosis and treatment strategies for ATN. MEDLINE search for all clinical studies of therapies for ATN, supplemented by a review of the references of the identified articles. Prospective studies and major retrospective studies evaluating therapies for ATN. Data on the study sample, interventions performed, results, side effects, and duration of follow-up. Early diagnosis of ATN by exclusion of prerenal and postrenal causes of acute renal failure, examination of urinary sediment, and analysis of urine measures (for example, fractional excretion of sodium in the absence of diuretics) can allow the early involvement of nephrologists and improve survival. Enteral rather than parenteral hyperalimentation in severely malnourished patients may improve survival. Sepsis causes 30% to 70% of deaths in patients with ATN; therefore, avoidance of intravenous lines, bladder catheters, and respirators is recommended. Because septic patients are vasodilated, large volumes of administered fluid accumulate in the lung interstitium of these patients. This condition necessitates ventilatory support, which when prolonged leads to acute respiratory distress syndrome, multiorgan failure, and increased mortality. More aggressive dialysis (for example, given daily) with biocompatible membranes may improve survival in some patients with acute renal failure. New information about the importance of early diagnosis and supportive care for patients with ATN has emerged. However, randomized trials of these interventions are needed to test their effect on the morbidity and mortality of ATN.

  11. Proximal tubular hypertrophy and enlarged glomerular and proximal tubular urinary space in obese subjects with proteinuria.

    Directory of Open Access Journals (Sweden)

    Ana Tobar

    Full Text Available BACKGROUND: Obesity is associated with glomerular hyperfiltration, increased proximal tubular sodium reabsorption, glomerular enlargement and renal hypertrophy. A single experimental study reported an increased glomerular urinary space in obese dogs. Whether proximal tubular volume is increased in obese subjects and whether their glomerular and tubular urinary spaces are enlarged is unknown. OBJECTIVE: To determine whether proximal tubules and glomerular and tubular urinary space are enlarged in obese subjects with proteinuria and glomerular hyperfiltration. METHODS: Kidney biopsies from 11 non-diabetic obese with proteinuria and 14 non-diabetic lean patients with a creatinine clearance above 50 ml/min and with mild or no interstitial fibrosis were retrospectively analyzed using morphometric methods. The cross-sectional area of the proximal tubular epithelium and lumen, the volume of the glomerular tuft and of Bowman's space and the nuclei number per tubular profile were estimated. RESULTS: Creatinine clearance was higher in the obese than in the lean group (P=0.03. Proteinuria was similarly increased in both groups. Compared to the lean group, the obese group displayed a 104% higher glomerular tuft volume (P=0.001, a 94% higher Bowman's space volume (P=0.003, a 33% higher cross-sectional area of the proximal tubular epithelium (P=0.02 and a 54% higher cross-sectional area of the proximal tubular lumen (P=0.01. The nuclei number per proximal tubular profile was similar in both groups, suggesting that the increase in tubular volume is due to hypertrophy and not to hyperplasia. CONCLUSIONS: Obesity-related glomerular hyperfiltration is associated with proximal tubular epithelial hypertrophy and increased glomerular and tubular urinary space volume in subjects with proteinuria. The expanded glomerular and urinary space is probably a direct consequence of glomerular hyperfiltration. These effects may be involved in the pathogenesis of obesity

  12. Transverse beam dynamics

    CERN Document Server

    Wilson, Edmund J N

    2006-01-01

    This contribution describes the transverse dynamics of particles in a synchrotron. It builds on other contributions to the General Accelerator School for definitions of transport matrices and lattice functions. After a discussion of the conservation laws which govern emittance, the effects of closed orbit distortion and other field errors are treated. A number of practical methods of measuring the transverse behaviour of particles are outlined.

  13. Iatrogenic Digital Compromise with Tubular Dressings

    Directory of Open Access Journals (Sweden)

    Corre, Kenneth A

    2009-08-01

    Full Text Available Objective: This case report describes a digit amputation resulting from an improperly applied tubular dressing. The safe application of digital tubular dressings, and the rationale behind it, is detailed to raise emergency physician (EP awareness.Methods: We present a case report of a recent iatrogenic-induced digit ischemia caused by improperly applied tube gauze. We review the literature on the subject and the likely sources of poor outcomes presented. The proper application of tubular gauze dressings is then outlined.Conclusion: EPs and emergency department personnel must be educated on the safe application of tubular gauze dressings to avoid dire outcomes associated with improper applications.[WestJEM. 2009;10:190-192.

  14. A neglected case of Renal Tubular Acidosis

    International Nuclear Information System (INIS)

    Derakhshan, A.; Basiratnia, M.; Fallahzadeh, M.H.; Al-Hashemi, G.H.

    2007-01-01

    In this report, we present a case of a child with distal renal tubular acidosis, severe failure to thrive and profound rickets, who was only 7.8 Kg when presented at 6 years of age. His response to treatment and his follow up for four years is discussed. Although failure to thrive is a common finding in renal tubular acidosis but the physical and x-ray findings in our case were unique. (author)

  15. The transverse spin

    Energy Technology Data Exchange (ETDEWEB)

    Artru, X. [Institut de Physique Nucleaire de Lyon, IN2P3-CNRS, Universite Claude Bernard, 43 boulevard du 11 Novembre 1918, F-69622 Villeurbanne (France)

    2002-07-01

    The aim of this introduction, which is far from exhaustive, was to give an overview on the richness of transverse spin quantity and its differences in comparison with helicity. From the experimental point of view, the physics of quark transversity in deep inelastic reaction is still practically unexplored. This situation will certainly change rapidly, with planned experiments at DESY (HERMES), Brookhaven (RHIC) and CERN (COMPAS), but there is a long way before knowing the transversity distribution, {delta}q(x), as precisely as the helicity distribution, {delta}q(x), now. Unless polarized anti-proton beams become feasible, experiments probing quark transversity will rely mainly on 'quark polarimeters', like {lambda}'s or the Collins effect. These polarimeters will have to be calibrated at e{sup +}e{sup -} colliders. The Collins polarimeter will by the way allow the flavor decomposition of {delta}q(x), using mesons of various charging and strangeness. Quark polarimetry is by itself an interesting topic of non-perturbative QCD, and may teach us something about the breaking of chiral symmetry. Let us recall that, if chiral symmetry were unbroken, transversity would be undefined. The transversity physics program is not at all a 'remake' of the helicity one. Helicity and transversity probe rather different aspects of the hadron structure. Differences between {delta}q(x) and {delta}q(x) will reveal non-relativistic effects in the baryon wave function. Also {delta}q(x) does not couples to gluon distributions, thus it is free from anomaly. In that respect it is a more clean probe than {delta}q(x). In fact, the combination of helicity and transversity measurements will perhaps be the most interesting. Polarized parton densities taking only the helicity degree of freedom are almost 'classical'. Quantum aspects of spin correlations, like violation of Bell's inequality, can be found only when varying the spin quantification axis

  16. Noninterceptive transverse beam diagnostics

    International Nuclear Information System (INIS)

    Chamberlin, D.D.; Minerbo, G.N.; Teel, L.E. Jr.; Gilpatrick, J.D.

    1981-01-01

    The transverse emittance properties of a high-current linear accelerator may be measured by using TV cameras sensitive to the visible radiation emitted following beam interactions with residual gas. This paper describes the TV system being used to measure emittances for the Fusion Materials Irradiation Test (FMIT) project

  17. Transition piece for joining together tubular pieces

    International Nuclear Information System (INIS)

    Holko, K.H.

    1981-01-01

    A transition piece for joining together tubular pieces formed respectively from a low alloy or carbon steel and a high temperature alloy containing at least 16% chromium includes a plurality of tubular parts welded together and formed from materials of selected composition with a maximum chromium content difference of 5% between adjacent parts when the chromium content of each part is below 10% and a maximum chromium difference of 7% between adjacent parts when the chromium content of either part is above 10%. The transition parts are also graded as to such characteristics as thermal expansion coefficient. The transition parts at opposite ends of the transition joint have chromium percentages similar to the tubular pieces to which they are to be joined. The parts may be joined by fusion and/or friction welding and parts may be formed by fusion weld deposition. (author)

  18. Platform technologies for tubular organ regeneration.

    Science.gov (United States)

    Basu, Joydeep; Ludlow, John W

    2010-10-01

    As a result of recent successes in regenerative medicine approaches to engineering multiple disparate tubular organs, methodology commonalities are emerging. Principal themes include the importance of a biodegradable scaffold seeded with a population of smooth muscle cells. Such composites trigger a regenerative response following in vivo implantation, resulting in de novo organogenesis. In this review, we examine bladder regeneration as a foundational platform technology to highlight key principles applicable to the regeneration of any tubular organ, and illustrate how these general concepts underlie current strategies to regenerate components of gastrointestinal, vascular, pulmonary and genitourinary systems. We focus on identifying the elements of this platform that have facilitated the transition of tubular organ regeneration from academic proof-of-concept to commercial viability. Copyright © 2010 Elsevier Ltd. All rights reserved.

  19. Ranitidine has no influence on tubular creatinine secretion

    NARCIS (Netherlands)

    van den Berg, J. G.; Koopman, M. G.; Arisz, L.

    1996-01-01

    Oral cimetidine competitively inhibits tubular secretion of creatinine. We investigated the potential of oral ranitidine, a comparable H2-receptor antagonist, to block tubular creatinine secretion. In 10 healthy subjects, clearances of inulin and endogenous creatinine were simultaneously measured

  20. Large transverse momentum phenomena

    International Nuclear Information System (INIS)

    Brodsky, S.J.

    1977-09-01

    It is pointed out that it is particularly significant that the quantum numbers of the leading particles are strongly correlated with the quantum numbers of the incident hadrons indicating that the valence quarks themselves are transferred to large p/sub t/. The crucial question is how they get there. Various hadron reactions are discussed covering the structure of exclusive reactions, inclusive reactions, normalization of inclusive cross sections, charge correlations, and jet production at large transverse momentum. 46 references

  1. Transverse tomography and radiotherapy

    International Nuclear Information System (INIS)

    Leer, J.W.H.

    1982-01-01

    This study was intended to delineate the indications for radiotherapy treatment-planning with the help of computerized axial tomography (C.T.) and transverse analog tomography (T.A.T.). Radiotherapy localisation procedures with the conventional method (simulator), with the CT-scanner and with the transverse analog tomograph (T.A.T., Simtomix, Oldelft) were compared. As criterium for evaluation differences in reconstruction drawing based on these methods were used. A certain method was judged ''superior'' to another if the delineation of the target volume was more accurate, if a better impression was gained of the site of (for irradiation) organs at risk, or if the localisation could only be performed with that method. The selected group of patients consisted of 120 patients for whom a reconstruction drawing in the transverse plane was made according to the treatment philosophy. In this group CT-assisted localisation was judged on 68 occasions superior to the conventional method. In a number of cases it was found that a ''standard'' change in a standard target volume, on the base of augmented anatomical knowledge, made the conventional method sufficient. The use of CT-scanner for treatment planning was estimated. For ca. 270/1000 new patients a CT-scan is helpful (diagnostic scan), for 140 of them the scan is necessary (planning scan). The quality of the anatomical information obtained with the T.A.T. does not yet fall within acceptable limits, but progress has been made. (Auth.)

  2. DOES TUBULARIZED INCISED PLATE URETHROPLASTY FIT ...

    African Journals Online (AJOL)

    Objective To evaluate prospectively our experience using tubularized incised plate (TIP) urethroplasty in primary and repeat penile shaft hypospadias. Patients and Methods Thirty-two boys with penile shaft hypospadias were selected to undergo TIP procedure. Their age ranged from 22 months to 9 years. Twenty-two cases ...

  3. Work tool in a tubular element

    International Nuclear Information System (INIS)

    Griffaton, J.

    1991-01-01

    The stand, which is positioned in relation with the tubular element, has clutch disengagement means for a working rod in rotation, with at least two positioning regions on the rod. Application for laser welding a sleeve into PWR steam generator tubes [fr

  4. Renal Tubular Function in Systemic Lupus Erythematosus*

    African Journals Online (AJOL)

    Creatinine clearance (Ccr), tubular reabsorption of phosphate (TRP) and maximum urinary osmolality. (OSM) 8 hours after injection of pitressin. Shaded are3.§ represent mean ± 2 SD of control values. was reduced in 2 patients, neither of whom showed evidence of hyperparathyroidism. Three patients were unable to ...

  5. Central Diabetes Insipidus, Central Hypothyroidism, Renal Tubular ...

    African Journals Online (AJOL)

    diseases, primary hypothyroidism, and other disorders of the central nervous, gastrointestinal, genitourinary, and orthopedic systems. In this report, we describe a 3‑month‑old Saudi boy with the rare association of DWS with central diabetes insipidus, congenital central hypothyroidism, and type‑2 renal tubular acidosis.

  6. TUBULAR DYSFUNCTION IN PROLIFERATIVE LUPUS NEPHRITIS

    NARCIS (Netherlands)

    TERBORG, E.J.; DEJONG, P.E.; MEIJER, S.S.; Kallenberg, Cees

    1991-01-01

    We prospectively studied renal tubular function during 11 consecutive exacerbations of proliferative glomerulonephritis in 8 patients with systemic lupus erythematosus (SLE). We found a rise in the fractional excretion of beta-2-microglobulin (p less-than-or-equal-to 0.05) and dimercaptosuccinic

  7. Modelling and simulation of a pervaporation process using tubular module for production of anhydrous ethanol

    Science.gov (United States)

    Hieu, Nguyen Huu

    2017-09-01

    Pervaporation is a potential process for the final step of ethanol biofuel production. In this study, a mathematical model was developed based on the resistance-in-series model and a simulation was carried out using the specialized simulation software COMSOL Multiphysics to describe a tubular type pervaporation module with membranes for the dehydration of ethanol solution. The permeance of membranes, operating conditions, and feed conditions in the simulation were referred from experimental data reported previously in literature. Accordingly, the simulated temperature and density profiles of pure water and ethanol-water mixture were validated based on existing published data.

  8. Reliability Analysis of Tubular Joints in Offshore Structures

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Sørensen, John Dalsgaard

    1987-01-01

    Reliability analysis of single tubular joints and offshore platforms with tubular joints is" presented. The failure modes considered are yielding, punching, buckling and fatigue failure. Element reliability as well as systems reliability approaches are used and illustrated by several examples....... Finally, optimal design of tubular.joints with reliability constraints is discussed and illustrated by an example....

  9. Twisted tubular photobioreactor fluid dynamics evaluation for energy consumption minimization

    NARCIS (Netherlands)

    Gómez-Pérez, C.A.; Espinosa Oviedo, J.J.; Montenegro Ruiz, L.C.; Boxtel, van A.J.B.

    2017-01-01

    This paper discusses a new tubular PhotoBioReactor (PBR) called twisted tubular PBR. The geometry of a twisted tubular PBR induces swirl mixing to guarantee good exposure of microalgae to Light-Dark (LD) cycles and to the nutrients and dissolved CO 2 . The paper analyses the energy uptake for fluid

  10. Distal renal tubular acidosis in recurrent renal stone formers

    DEFF Research Database (Denmark)

    Osther, P J; Hansen, A B; Røhl, H F

    1989-01-01

    (1.1%) had complete distal renal tubular acidosis and 14 (15.5%) incomplete distal renal tubular acidosis. Our results confirm that distal renal tubular acidification defects are associated with a more severe form of stone disease and make distal renal tubular acidosis one of the most frequent...... metabolic disturbances in renal stone formers. Distal renal tubular acidosis (dRTA) was relatively more common in female stone formers and most often found in patients with bilateral stone disease (36%). Since prophylactic treatment in renal stone formers with renal acidification defects is available...

  11. Figures of transversality

    DEFF Research Database (Denmark)

    Gammeltoft, Tine

    2008-01-01

    In this article, I explore how prenatal screening is imbricated within state agendas, aspirations, and imaginings in contemporary Vietnam. In an effort to develop new ethnographic tropes for understanding the formation called "the state," I argue for a phenomenological take that emphasizes its...... affective and embodied aspects. Seeing the anomalous fetus as a "figure of transversality," as a critical focus for powerful imaginings and desires, I show how state–society relations in Vietnam are suffused by visceral affectivity and moral engagement. In the realm of reproduction, intense sentiments...... of anxiety, dread, desire, ambition, and hope tie together the state and its citizens, animating individual aspirations as well as national population policies....

  12. Study of hydrodynamic characteristics in tubular photobioreactors.

    Science.gov (United States)

    Zhang, Qinghua; Wu, Xia; Xue, Shengzhang; Liang, Kehong; Cong, Wei

    2013-02-01

    In this work, the hydrodynamic characteristics in tubular photobioreactors with a series of helical static mixers built-in were numerically investigated using computational fluid dynamics (CFD). The influences of height and screw pitch of the helical static mixer and fluid inlet velocity on the cell trajectories, swirl numbers and energy consumption were examined. In order to verify the actual results for cultivation of microalgae, cultivation experiments of freshwater Chlorella sp. were carried out in photobioreactor with and without helical static mixer built-in at the same time. It was shown that with built-in helical static mixer, the mixing of fluid could be intensified, and the light/dark cycle could also be achieved which is of benefit for the growth of microalgae. The biomass productivity of Chlorella sp. in tubular photobioreactor with helical static mixer built-in was 37.26 % higher than that in the photobioreactor without helical static mixer.

  13. SOFC mini-tubulares basadas en YSZ

    Directory of Open Access Journals (Sweden)

    Campana, R.

    2008-08-01

    Full Text Available Tubular SOFC have the advantage over planar SOFC of the low temperature sealing and more resistance to thermal shock. On the other hand the volumetric power density of tubular Fuel Cells goes with the inverse of the tube diameter which added to the faster warm-up kinetics makes low diameter tubular SOFC favorable for low power applications. Anode supported tubular SOFC of 3mm diameter and 150 mm length with YSZ electrolyte were fabricated and tested by V-I measurements using H2-Ar (5, 10, 100 vol% as fuel and air for the cathode. The NiO-YSZ tubes of about 400 μm thickness were produced by hydrostatic pressure and then coated with an YSZ film of 15-20 μm. The electrolyte was deposited using a manual aerograph. After sintering either Pt paste or LSF (with YSZ or SDC coatings of about 20-50 μm thickness were deposited for the cathode. The OCV of the cells were excellent, very close to the expected Nernst law prediction indicating that there were not gas leaks. The maximun electrical power of the cell was near to 500mW/cm2 at 850ºC operation temperature. Complex impedance measurements of the cells were performed in order to determine the resistance of the different cell components.

    La principal ventaja de las SOFC tubulares frente a las planares es el sellado de la cámara anódica y catódica a bajas temperaturas. Además la densidad de energía volumétrica de las pilas tubulares es inversamente proporcional al diámetro del tubo, que añadido a los tiempos cortos de encendido y apagado hacen que las mini-tubulares sean interesantes para usos de baja potencia. Se han fabricado y caracterizado SOFC tubulares soportadas en ánodo de 3mm de diámetro y de 150 mm de longitud, 400μm de espesor, con electrolito de YSZ depositado por spray de 15-20 μm. Los tubos de NiO-YSZ son producidos por prensado isostático. La caracterización eléctrica se ha realizado empleando H2-Ar como combustible an

  14. Forming of Polymeric Tubular Micro-components

    DEFF Research Database (Denmark)

    Qin, Yi; Zhao, Jie; Anyasodor, Gerald

    2015-01-01

    platform for the production of functional polymeric tubular micro-components. The chapter gives background on the current market and process development trends, followed by description of materials, process configuration, tool design and machine development for each processing technology as well...... as strategy for integration of the technologies and equipment into a common platform. Finally, potential applications of the technologies and facilities developed are highlighted....

  15. Renal Tubular Toxicity Associated With Rosuvastatin Therapy.

    Science.gov (United States)

    Ward, Frank L; John, Rohan; Bargman, Joanne M; McQuillan, Rory F

    2017-03-01

    Preapproval clinical trials examining the safety and efficacy of rosuvastatin demonstrated an increased incidence of proteinuria, hematuria, rhabdomyolysis, and other acute kidney injury of unknown cause at high doses. The latter cases manifested with urine sediment findings and in some cases, renal histology, indicating renal tubular injury in the absence of rhabdomyolysis. Despite these provocative findings, there have been very few reports in the literature regarding non-rhabdomyolysis-mediated acute kidney injury associated with high-dose rosuvastatin since its widespread introduction more than a decade ago, suggesting that it is either a rare entity or systematically underdiagnosed and under-reported. We present a case of renal tubular toxicity attributable to the initiation of rosuvastatin treatment at a dose of 40mg in a patient with no prior evidence of kidney disease. Tubular toxicity should be considered in cases of unexplained kidney injury in the setting of exposure to a potent statin such as rosuvastatin, particularly at high dose. The limited evidence suggests a good kidney prognosis following withdrawal of the agent in these cases. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  16. Hydrogen-selective membrane

    Science.gov (United States)

    Collins, J.P.; Way, J.D.

    1997-07-29

    A hydrogen-selective membrane comprises a tubular porous ceramic support having a palladium metal layer deposited on an inside surface of the ceramic support. The thickness of the palladium layer is greater than about 10 {micro}m but typically less than about 20 {micro}m. The hydrogen permeation rate of the membrane is greater than about 1.0 moles/m{sup 2} s at a temperature of greater than about 500 C and a transmembrane pressure difference of about 1,500 kPa. Moreover, the hydrogen-to-nitrogen selectivity is greater than about 600 at a temperature of greater than about 500 C and a transmembrane pressure of about 700 kPa. Hydrogen can be separated from a mixture of gases using the membrane. The method may include the step of heating the mixture of gases to a temperature of greater than about 400 C and less than about 1000 C before the step of flowing the mixture of gases past the membrane. The mixture of gases may include ammonia. The ammonia typically is decomposed to provide nitrogen and hydrogen using a catalyst such as nickel. The catalyst may be placed inside the tubular ceramic support. The mixture of gases may be supplied by an industrial process such as the mixture of exhaust gases from the IGCC process. 9 figs.

  17. The management of transverse lie in labour | Edelstein | South ...

    African Journals Online (AJOL)

    The management of 410 cases of transverse lie in labour at Baragwanath Hospical during the period 1964 - 1968 is analysed. Two conclusions may be drawn. Caesarean section should be performed in the fol/owing cases: (a) In patients in whom the membranes have been ruptured-a classical caesarean seclion is ...

  18. Transmission Characteristics in Tubular Acoustic Metamaterials Studied with Fluid Impedance Theory

    International Nuclear Information System (INIS)

    Fan Li; Zhang Shu-Yi; Zhang Hui

    2011-01-01

    Tubular acoustic metamaterials with negative densities composed of periodical membranes set up along pipes are studied with the fluid impedance theory. In addition to the conventional forbidden bands induced by the Bragg-scattering due to the periodic distributions of different acoustic impedances, the low-frequency forbidden band (LFB) with the low-frequency limit of zero Hertz is studied, in which the LFB is explained with acoustic impedance matching and the Bloch theory. Furthermore, the influences of the structural parameters of the tubular acoustic metamaterials on the transmission characteristics, such as the transmission coefficients, dispersion curves, widths of forbidden and pass bands, fluctuations in pass bands, etc., are evaluated, which can be used in the optimization of the acoustic insulation ability of the metamaterials. (fundamental areas of phenomenology (including applications))

  19. Transverse section scanning mechanism

    International Nuclear Information System (INIS)

    Doherty, E.J.

    1978-01-01

    Apparatus is described for scanning a transverse, radionuclide scan-field using an array of focussed collimators. The collimators are movable tangentially on rails, driven by a single motor via a coupled screw. The collimators are also movable in a radial direction on rails driven by a step motor via coupled screws and bevel gears. Adjacent bevel gears rotate in opposite directions so adjacent collimators move in radially opposite directions. In use, the focal point of each collimator scans at least half of the scan-field, e.g. a human head located in the central aperture, and the electrical outputs of detectors associated with each collimator are used to determine the distribution of radioactive emission intensity at a number of points in the scan-field. (author)

  20. Quantification and localization of M2 macrophages in human kidneys with acute tubular injury

    Directory of Open Access Journals (Sweden)

    Palmer MB

    2014-11-01

    Full Text Available Matthew B Palmer,1 Alfred A Vichot,2 Lloyd G Cantley,2 Gilbert W Moeckel1 1Department of Pathology, Yale University School of Medicine, New Haven, CT, USA; 2Department of Medicine, Yale University School of Medicine, New Haven, CT, USA Abstract: This study addresses for the first time the question whether there is significant macrophage population in human kidney sections from patients with acute tubular injury (ATI. We examined therefore the interstitial macrophage population in human kidney tissue with biopsy-proven diagnosis of ATI, minimal change disease (MCD, and MCD with ATI. Kidney biopsies from patients with the above diagnoses were stained with antibodies directed against CD68 (general macrophage marker, CD163 (M2 marker, and HLA-DR (M1 marker and their respective electron microscopy samples were evaluated for the presence of interstitial macrophages. Our study shows that patients with ATI have significantly increased numbers of interstitial CD68+ macrophages, with an increase in both HLA-DR+ M1 macrophages and CD163+ M2 macrophages as compared to patients with MCD alone. Approximately 75% of macrophages were M2 (CD163+ whereas only 25% were M1 (HLA-DR+. M2 macrophages, which are believed to be critical for wound healing, were found to localize close to the tubular basement membrane of injured proximal tubule cells. Ultra structural examination showed close adherence of macrophages to the basement membrane of injured tubular epithelial cells. We conclude that macrophages accumulate around injured tubules following ATI and exhibit predominantly an M2 phenotype. We further speculate that macrophage-mediated repair may involve physical contact between the M2 macrophage and the injured tubular epithelial cell. Keywords: macrophages, acute kidney injury, CD163, HLA-DR, CD68, electron microscopy

  1. Oxygen transport membrane system and method for transferring heat to catalytic/process reactors

    Science.gov (United States)

    Kelly, Sean M; Kromer, Brian R; Litwin, Michael M; Rosen, Lee J; Christie, Gervase Maxwell; Wilson, Jamie R; Kosowski, Lawrence W; Robinson, Charles

    2014-01-07

    A method and apparatus for producing heat used in a synthesis gas production is provided. The disclosed method and apparatus include a plurality of tubular oxygen transport membrane elements adapted to separate oxygen from an oxygen containing stream contacting the retentate side of the membrane elements. The permeated oxygen is combusted with a hydrogen containing synthesis gas stream contacting the permeate side of the tubular oxygen transport membrane elements thereby generating a reaction product stream and radiant heat. The present method and apparatus also includes at least one catalytic reactor containing a catalyst to promote the stream reforming reaction wherein the catalytic reactor is surrounded by the plurality of tubular oxygen transport membrane elements. The view factor between the catalytic reactor and the plurality of tubular oxygen transport membrane elements radiating heat to the catalytic reactor is greater than or equal to 0.5.

  2. Neutron diffraction investigations on residual stresses contributing to the fatigue crack growth in ferritic steel tubular bridges

    International Nuclear Information System (INIS)

    Acevedo, C.; Evans, A.; Nussbaumer, A.

    2012-01-01

    Fatigue crack growth observed in tubular K-joint specimens, typical of tubular bridge structures, always initiates at the chord crown toe locations whether the applied stress range is tensile or compressive. Even though other locations around the weld have highest hot-spot stresses, chord crown toe locations are still the most critical. This raises the question about the relevant tensile residual stress level at that location. The results of residual stress investigations, obtained using neutron diffraction measurements highlight that the direction and location of the maximum tensile residual stresses in K-joints is substantially different from those in the more usual tubular butt joints. Indeed, it is shown that the highest tensile residual stresses are oriented perpendicular to the weld direction, which is also the main orientation of the loading stresses applied in K-joints. This paper demonstrates that it is the complex geometry of the K-joint that causes the superposition of critical stresses, making these joints susceptible to fatigue cracking. Therefore, transverse residual stresses play a crucial part in the fatigue crack growth behaviour that applied stresses alone cannot explain. Highlights: ► We measure the 3D residual stresses in tubular joints using neutron diffraction. ► We identify direction and location of the maximum tensile residual stresses. ► K-joint geometry will induce a non-usual orientation of residual stresses. ► Fatigue crack propagation is affected by this critical stress orientation.

  3. Cathepsin D protects renal tubular cells from damage induced by high glucose independent of its enzymatic activity.

    Science.gov (United States)

    Du, Feng; Wang, Tian; Li, Si; Meng, Xin; Zhang, Hai-Yan; Li, De-Tian; Du, Zhen-Xian; Wang, Hua-Qin

    2017-01-01

    Although glomerular and vascular damage have been considered the main characteristics of diabetic kidney disease (DKD), accumulating data now indicate that tubular atrophy also plays a major role. Cathepsin D (CatD) is the major aspartate protease within lysosomes. The current study demonstrated that CatD expression was altered in the renal tubular epithelium in patients with diabetes mellitus (DM). In contrast to its low and uniform distribution in the tubular epithelium in normal kidney tissues, CatD demonstrated flecked and increased expression in tubules with relatively integral structures, and disappeared in disordered tubules in DM kidney tissues. In vitro studies demonstrated that CatD protected HK2 cells from the damage induced by high glucose and advanced glycation end-products (AGEs), independent of its enzymatic activity. In addition, the current study demonstrated that AGEs induced lysosome membrane permeabilization (LMP) and loss of mitochondrial membrane potential (MMP). Overexpression of CatD prevented LMP and maintained the MMP in HK2 cells exposed to AGEs. In addition, the catalytic activity of CatD was not required for its role in LMP prevention and MMP maintenance. These results indicate, for the first time that CatD may improve the viability of renal tubular cells in the presence of diabetic mediators independent of its enzymatic activity by preventing LMP and stabilizing the MMP.

  4. Distal renal tubular acidosis in recurrent renal stone formers

    DEFF Research Database (Denmark)

    Osther, P J; Hansen, A B; Røhl, H F

    1989-01-01

    Renal acidification ability was examined in 90 recurrent renal stone formers, using fasting morning urinary pH levels followed by a short ammonium chloride loading test in subjects with pH levels above 6.0. Fifteen patients (16.6%) revealed a distal renal tubular acidification defect: one patient...... (1.1%) had complete distal renal tubular acidosis and 14 (15.5%) incomplete distal renal tubular acidosis. Our results confirm that distal renal tubular acidification defects are associated with a more severe form of stone disease and make distal renal tubular acidosis one of the most frequent...... metabolic disturbances in renal stone formers. Distal renal tubular acidosis (dRTA) was relatively more common in female stone formers and most often found in patients with bilateral stone disease (36%). Since prophylactic treatment in renal stone formers with renal acidification defects is available...

  5. Luminal nucleotides are tonic inhibitors of renal tubular transport

    DEFF Research Database (Denmark)

    Leipziger, Jens Georg

    2011-01-01

    PURPOSE OF REVIEW: Extracellular ATP is an essential local signaling molecule in all organ systems. In the kidney, purinergic signaling is involved in an array of functions and this review highlights those of relevance for renal tubular transport. RECENT FINDINGS: Purinergic receptors are expressed...... in all renal tubular segments and their stimulation generally leads to transport inhibition. Recent evidence has identified the tubular lumen as a restricted space for purinergic signaling. The concentrations of ATP in the luminal fluids are sufficiently high to inflict a tonic inhibition of renal...... tubular absorption via P2 receptors. The apical P2Y2 receptor plays a crucial role in this process. ATP is released continuously into the tubular lumen. The release is augmented in response to an increase of tubular flow and after stimulation of G-protein-coupled receptors. The primary cilium appears...

  6. Classical Weyl transverse gravity

    Energy Technology Data Exchange (ETDEWEB)

    Oda, Ichiro [University of the Ryukyus, Department of Physics, Faculty of Science, Nishihara, Okinawa (Japan)

    2017-05-15

    We study various classical aspects of the Weyl transverse (WTDiff) gravity in a general space-time dimension. First of all, we clarify a classical equivalence among three kinds of gravitational theories, those are, the conformally invariant scalar tensor gravity, Einstein's general relativity and the WTDiff gravity via the gauge-fixing procedure. Secondly, we show that in the WTDiff gravity the cosmological constant is a mere integration constant as in unimodular gravity, but it does not receive any radiative corrections unlike the unimodular gravity. A key point in this proof is to construct a covariantly conserved energy-momentum tensor, which is achieved on the basis of this equivalence relation. Thirdly, we demonstrate that the Noether current for the Weyl transformation is identically vanishing, thereby implying that the Weyl symmetry existing in both the conformally invariant scalar tensor gravity and the WTDiff gravity is a ''fake'' symmetry. We find it possible to extend this proof to all matter fields, i.e. the Weyl-invariant scalar, vector and spinor fields. Fourthly, it is explicitly shown that in the WTDiff gravity the Schwarzschild black hole metric and a charged black hole one are classical solutions to the equations of motion only when they are expressed in the Cartesian coordinate system. Finally, we consider the Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmology and provide some exact solutions. (orig.)

  7. Hot Firing of a Full Scale Copper Tubular Combustion Chamber

    National Research Council Canada - National Science Library

    Cooley, C

    2002-01-01

    .... The AEC copper tubular design combines high material thermal conductivity and large effective surface area in a structurally compliant coolant channel configuration to achieve significant heat pick...

  8. Carbon Tubular Morphologies in Blast Furnace Coke

    Directory of Open Access Journals (Sweden)

    Stanislav S. Gornostayev

    2008-01-01

    Full Text Available The paper reports on the first occurrence of microscale carbon tubular morphologies (CMTs in a blast furnace (BF coke. The CMTs were probably formed as a result of the conversion of solid disordered carbon via liquid phase metal particles involving a gas phase containing a substantial amount of N2 and O2. The presence of CMTs may lie behind the generation of the smallest fraction of fines in BF exhaust dust. If the amount of CMTs present in the BF exhausts gases at any particular metallurgical site proves to be substantial, it could become a subject of environmental concern.

  9. Keyhole defect production in tubular bone.

    Science.gov (United States)

    Berryman, H E; Gunther, W M

    2000-03-01

    Fracture characteristics, reported primarily for the cranium, are valuable indicators of bullet direction. A bullet striking the vault tangentially produces an irregular opening, termed a "keyhole defect." with the circular portion of the defect being the initial point of impact. Identifying this feature in tubular bone (long bone) can also demonstrate bullet direction and the position of the bone at the time of the shooting. This case study involving a tangential shot (i.e., a keyhole fracture) to the humerus demonstrates some of the same fracture mechanics seen in the cranium.

  10. Fractal solutions of recirculation tubular chemical reactors

    International Nuclear Information System (INIS)

    Berezowski, Marek

    2003-01-01

    Three kinds of fractal solutions of model of recirculation non-adiabatic tubular chemical reactors are presented. The first kind concerns the structure of Feigenbaum's diagram on the limit of chaos. The second kind and the third one concern the effect of initial conditions on the dynamic solutions of models. In the course of computations two types of recirculation were considered, viz. the recirculation of mass (return of a part of products' stream) and recirculation of heat (heat exchange in the external heat exchanger)

  11. Analysis of efforts on a tubular chassis

    OpenAIRE

    Pérez Ripa, Diego

    2011-01-01

    The objective of this project is to design a tubular chassis of a speed car, based on a earlier design of this type of car. When it is designed, the aim is to design it with a finite element program, in this case, is going to be used the software Abaqus, for after establish a method of calculation in a manner in which can be measured all the parameters, like deformations and stresses, suffered by the chassis submited to the efforts supported by the chassis in different situatio...

  12. TUBULAR DISORDERS WITH RICKETS-LIKE SYNDROME

    Directory of Open Access Journals (Sweden)

    N.N. Kartamysheva

    2011-01-01

    Full Text Available Often under the guise of «ordinary» Rickets are more severe kidney diseases, developing as a result of inherited or acquired, primary or secondary defects in the renal tubules. Incorrect diagnosis leads to an inadequate therapy, rapid progression of disease and renal failure. The article describes the main approaches to the diagnosis and treatment of disorders of tubular rachitis similar syndrome, presents a number of clinical cases in author's practice.Key words: tubulopathy, acidosis, electrolyte disorders, rickets, rickets-like syndrome, diagnostics, treatment, children.

  13. Tubular fluoropolymer arrays with high piezoelectric response

    Science.gov (United States)

    Zhukov, Sergey; Eder-Goy, Dagmar; Biethan, Corinna; Fedosov, Sergey; Xu, Bai-Xiang; von Seggern, Heinz

    2018-01-01

    Polymers with electrically charged internal air cavities called ferroelectrets exhibit a pronounced piezoelectric effect and are regarded as soft functional materials suitable for sensor and actuator applications. In this work, a simple method for fabricating piezoelectret arrays with open-tubular channels is introduced. A set of individual fluoroethylenepropylene (FEP) tubes is compressed between two heated metal plates. The squeezed FEP tubes are melted together at +270 °C. The resulting structure is a uniform, multi-tubular, flat array that reveals a strong piezoelectric response after a poling step. The fabricated arrays have a high ratio between piezoelectrically active and non-active areas. The optimal charging voltage and stability of the piezoelectric coefficients with pressures and frequency were experimentally investigated for two specific array structures with wall thickness of 50 and 120 μm. The array fabricated from 50 μm thick FEP tubes reveals a stable and high piezoelectric coefficient of {d}33 = 120-160 pC N-1 with a flat frequency response between 0.1 Hz and 10 kHz for pressures between 1 and 100 kPa. An increase of wall thickness to 120 μm is accompanied by a more than twofold decrease in the piezoelectric coefficient as a result of a simultaneously higher effective array stiffness and lower remanent polarization. The obtained experimental results can be used to optimize the array design with regard to the electromechanical performance.

  14. A novel tubular microbial electrolysis cell for high rate hydrogen production

    Science.gov (United States)

    Guo, Kun; Prévoteau, Antonin; Rabaey, Korneel

    2017-07-01

    Practical application of microbial electrolysis cells (MECs) for hydrogen production requires scalable reactors with low internal resistance, high current density, and high hydrogen recovery. This work reports a liter scale tubular MEC approaching these requirements. The tubular cell components (a platinum-coated titanium mesh cathode, an anion exchange membrane, and a pleated stainless steel felt anode) were arranged in a concentric configuration. The reactor had a low internal resistance (0.325 Ω, 19.5 mΩ m2) due to the high conductivity of the electrodes, a compact reactor configuration, and proper mixing. With acetate as electron donor, the MEC achieved a volumetric current density of 654 ± 22 mA L-1 (projected current density, 1.09 ± 0.04 mA cm-2) and a volumetric hydrogen production rate of 7.10 ± 0.01 L L-1 d-1 at an applied voltage of 1 V. The reactor also showed high hydrogen recovery (∼100%), high hydrogen purity (>98%), and excellent operational stability during the 3 weeks of operation. These results demonstrated that high hydrogen production rate could be achieved on larger scale MEC and this tubular MEC holds great potential for scaling up.

  15. Analysis of an active tubular liquid-feed direct methanol fuel cell

    Science.gov (United States)

    Xu, Chao; Faghri, Amir

    2011-08-01

    A two-dimensional, two-phase, non-isothermal model was developed for an active, tubular, liquid-feed direct methanol fuel cell (DMFC). The liquid-gas, two-phase mass transport in the porous anode and cathode was formulated based on the multi-fluid approach in the porous media. The two-phase mass transport in the anode and cathode channels was modeled using the drift-flux and the homogeneous mist-flow models, respectively. Water and methanol crossovers through the membrane were considered due to the effects of diffusion, electro-osmotic drag, and convection. The model enabled a numerical investigation of the effects of various operating parameters, such as current density, methanol flow rate, and oxygen flow rate, on the mass and heat transport characteristics in the tubular DMFC. It was shown that by choosing a proper tube radius and distance between the adjacent cells, a tubular DMFC stack can achieve a much higher energy density compared to its planar counterpart. The results also showed that a large anode flow rate is needed in order to avoid severe blockage of liquid methanol to the anode electrode due to the gas accumulation in the channel. Besides, lowering the flow rate of either the methanol solution or air can lead to a temperature increase along the flow channel. The methanol and water crossovers are nearly independent of the methanol flow rate and the air flow rate.

  16. [Long-term efficacy of tubularized peritoneal free grafts as ureteral mucosal substitutes in dogs].

    Science.gov (United States)

    Jing, Yi-Feng; Xia, Shu-Jie; Li, Du-Jian; Guo, Wen-Huan; Xu, Yao-Ting

    2011-02-15

    To investigate the long-term efficacy of ureteral reconstruction with tubularized peritoneal free grafts for the treatment of avulsion of ureteral mucosa in animal models. The model of avulsion of ureteral mucosa was established in 12 adult dogs. Then they were divided into Group A (n = 6, length of avulsed mucosa at 4 cm) and Group B (n = 6, length of avulsed mucosa at 6 cm). And the tubularized peritoneal free grafts and ureteral stents were implanted into the injured ureters. The curative effect was observed by intravenous urethrogram (IVU) and histological examination at Week 24 post-operation. Severe stenosis was observed by IVU in 1 dogs in Groups A and B respectively. In the remaining 10 dogs, IVU showed normal size and morphology of kidneys. There was no hydronephrosis. And no obvious stricture of ureteral part was observed for mucosa substitutes made of peritoneal free grafts. In all 10 dogs without stenosis of both groups, peritoneal membrane was replaced by integrated transitional epithelium. And there was no obvious stricture. Collagen fibers were arranged parallel to mucosal surface. For avulsion of ureteral mucosa under 6 cm, reconstruction with tubularized peritoneal free grafts as mucosa substitutes is an effective method. And its long-term efficacy is satisfactory.

  17. Overendocytosis of gold nanoparticles increases autophagy and apoptosis in hypoxic human renal proximal tubular cells

    Directory of Open Access Journals (Sweden)

    Ding F

    2014-09-01

    production of reactive oxygen species, the loss of mitochondrial membrane potential (ΔΨM, and an increase in apoptosis and autophagic cell death. Conclusion/significance: Our results demonstrate that renal tubular epithelial cells presented different responses under normoxic and hypoxic environments, which provide an important basis for understanding the risks associated with GNP use–especially for the potential GNP-related therapies in chronic kidney disease patients. Keywords: gold nanoparticles (GNPs, toxicity, autophagy, apoptosis 

  18. Specific estrogen-induced cell proliferation of cultured Syrian hamster renal proximal tubular cells in serum-free chemically defined media

    International Nuclear Information System (INIS)

    Oberley, T.D.; Lauchner, L.J.; Pugh, T.D.; Gonzalez, A.; Goldfarb, S.; Li, S.A.; Li, J.J.

    1989-01-01

    It has long been recognized that the renal proximal tubular epithelium of the hamster is a bona fide estrogen target tissue. The effect of estrogens on the growth of proximal tubule cell explants and dissociated single cells derived from these explant outgrowths has been studied in culture. Renal tubular cells were grown on a PF-HR-9 basement membrane under serum-free chemically defined culture conditions. At 7-14 days in culture, cell number was enhanced 3-fold in the presence of either 17β-estradiol or diethylstilbestrol. A similar 3-fold increase in cell number was also seen at 1 nM 17β-estradiol in subcultured dissociated single tubular cells derived from hamster renal tubular explant outgrowths at 21 days in culture. Concomitant exposure of tamoxifen at 3-fold molar excess in culture completely abolished the increase in cell number seen with 17β-estradiol. The proliferation effect of estrogens on proximal tubular cell growth appears to be species specific since 17β-estradiol did not alter the growth of either rat or guinea pig proximal tubules in culture. In addition, at 7-10 days in culture in the presence of 17β-estradiol, [ 3 H]thymidine labeling of hamster tubular cells was enhanced 3-fold. These results clearly indicate that estrogens can directly induce primary epithelial cell proliferation at physiologic concentrations and provide strong additional evidence for an important hormonal role in the neoplastic transformation of the hamster kidney

  19. Cyclosporine A induces senescence in renal tubular epithelial cells

    NARCIS (Netherlands)

    Jennings, Paul; Koppelstaetter, Christian; Aydin, Sonia; Abberger, Thomas; Wolf, Anna Maria; Mayer, Gert; Pfaller, Walter

    The nephrotoxic potential of the widely used immunosuppressive agent cyclosporine A (CsA) is well recognized. However, the mechanism of renal tubular toxicity is not yet fully elucidated. Chronic CsA nephropathy and renal organ aging share some clinical features, such as renal fibrosis and tubular

  20. Intrarenal purinergic signaling in the control of renal tubular transport

    DEFF Research Database (Denmark)

    Prætorius, Helle; Leipziger, Jens Georg

    2010-01-01

    -reaching advances indicate that ATP is often used as a local transmitter for classical sensory transduction. This transmission apparently also applies to sensory functions in the kidney. Locally released ATP is involved in sensing of renal tubular flow or in detecting the distal tubular load of NaCl at the macula...

  1. Weingarten and Linear Weingarten Type Tubular Surfaces in E3

    Directory of Open Access Journals (Sweden)

    Yılmaz Tunçer

    2011-01-01

    Full Text Available We study tubular surfaces in Euclidean 3-space satisfying some equations in terms of the Gaussian curvature, the mean curvature, the second Gaussian curvature, and the second mean curvature. This paper is a completion of Weingarten and linear Weingarten tubular surfaces in Euclidean 3-space.

  2. Endothelial protein C receptor in renal tubular epithelial cells and ...

    African Journals Online (AJOL)

    This study aims to investigate EPCR expression in renal tubular epithelial cells and related influencing factors. EPCR expression was assessed by flow cytometry in renal tubular epithelial cells. The effects of some reagents (high glucose, tumor necrosis factor–α and interleukin-1β) were measured by RT-PCR. The results ...

  3. Theoretical and experimental investigations of Chinese evacuated tubular solar collectors

    DEFF Research Database (Denmark)

    Qin, Lin; Furbo, Simon

    1999-01-01

    Four different marketed Chinese evacuated tubular solar collectors have been investigated both theoretically and experimentally. The advantages of the investigated solar collectors compared to normal flat plate collectors were elucidated.......Four different marketed Chinese evacuated tubular solar collectors have been investigated both theoretically and experimentally. The advantages of the investigated solar collectors compared to normal flat plate collectors were elucidated....

  4. Apoptotic tubular cell death during acute renal allograft rejection

    NARCIS (Netherlands)

    Wever, P. C.; Aten, J.; Rentenaar, R. J.; Hack, C. E.; Koopman, G.; Weening, J. J.; ten Berge, I. J.

    1998-01-01

    Tubular cells are important targets during acute renal allograft rejection and induction of apoptosis might be a mechanism of tubular cell destruction. Susceptibility to induction of apoptosis is regulated by the homologous Bcl-2 and Bax proteins. Expression of Bcl-2 and Bax is regulated by p53,

  5. A Long Term Test of Differently Designed Evacuated Tubular Collectors

    DEFF Research Database (Denmark)

    Fan, Jianhua; Dragsted, Janne; Furbo, Simon

    2008-01-01

    During three years seven differently designed evacuated tubular collectors (ETCs) utilizing solar radiation from all directions have been investigated experimentally. The evacuated tubular solar collectors investigated include one SLL all-glass ETC from Tshinghua Solar Co. Ltd, four heat pipe ETCs...

  6. Renal Tubular Function in Systemic Lupus Erythematosus | Jessop ...

    African Journals Online (AJOL)

    Renal function is commonly assessed by measurement of glomerular filtration rate (GFR). However, defects in tubular function may still exist in the presence of a normal GFR. In 12 patients with systemic lupus erythematosus (SLE), 6 of whom had previously been shown to have renal impairment, glomerular and tubular ...

  7. Failure Modes of thin supported Membranes

    DEFF Research Database (Denmark)

    Hendriksen, Peter Vang; Høgsberg, J.R.; Kjeldsen, Ane Mette

    2007-01-01

    Four different failure modes relevant to tubular supported membranes (thin dense films on a thick porous support) were analyzed. The failure modes were: 1) Structural collapse due to external pressure 2) burst of locally unsupported areas, 3) formation of surface cracks in the membrane due to TEC......-mismatches, and finally 4) delamination between membrane and support due to expansion of the membrane on use. Design criteria to minimize risk of failure by the four different modes are discussed. The theoretical analysis of the two last failure modes is compared to failures observed on actual components....

  8. Evaluation of renal glomerular and tubular functional and structural integrity in neonates.

    Science.gov (United States)

    Awad, Hesham; el-Safty, Ibrahim; el-Barbary, Mohamed; Imam, Safaa

    2002-11-01

    Renal cells are not fully differentiated at birth, representing a major risk in preterm infants. We evaluated glomerular and tubular functional integrity as well as structural integrity of renal tubules among healthy full-term and preterm infants as well as diseased preterm infants. A total of 50 newborns (10 healthy full-term, 10 healthy preterm, and 30 diseased preterm, at 38.9 +/- 1.10, 34.2 +/- 0.92, and 32 +/- 2.47 weeks gestational age, respectively) were included in the present study. Glomerular function was assessed by measuring urinary levels of both microalbumin and immunoglobulin G as well as serum creatinine levels, whereas the proximal tubular function was investigated by measuring the urinary levels of both alpha1-microglobulin and beta2-microglobulin as well as retinol-binding protein. Also, distal tubular reabsorption capacity was investigated by assessing fractional excretion of sodium. Moreover, the structural integrity of renal proximal tubules was studied by measuring the urinary activities of both the brush-border membrane enzyme leucine-aminopeptidase (LAP) and the lysosomal enzyme N-acetyl-beta-D-glucosaminidase. The preceding investigations were done on both the first and third days of life of all 50 newborns. Glomerular and tubular function and structure was relatively impaired at birth among both healthy and diseased preterm as well as healthy full-term neonates and improved rapidly thereafter. The diseased preterm neonates showed worse renal function and structure with minimal improvement regardless of the underlying sickness. Renal insufficiency and renal immaturity could be evaluated using enzymuria and low- and high-molecular-weight proteinuria as noninvasive methods.

  9. Transverse correlations in multiphoton entanglement

    International Nuclear Information System (INIS)

    Wen Jianming; Rubin, Morton H.; Shih Yanhua

    2007-01-01

    We have analyzed the transverse correlation in multiphoton entanglement. The generalization of quantum ghost imaging is extended to the N-photon state. The Klyshko's two-photon advanced-wave picture is generalized to the N-photon case

  10. Inherited renal tubular defects with hypokalemia

    Directory of Open Access Journals (Sweden)

    Muthukrishnan J

    2009-01-01

    Full Text Available Bartter′s and Gitelman′s syndrome are two ends of a spectrum of inherited renal tubular disorders that present with hypokalemic metabolic alkalosis of varying severity. Clinical features and associated calcium and magnesium ion abnormalities are used to diagnose these cases after excluding other commoner causes. We report on two cases, the first being a young boy, born of pregnancy complicated by polyhydramnios, who had classical dysmorphic features, polyuria, hypokalemia and hypercalciuria and was diagnosed as having Bartter′s syndrome. The second patient is a lady who had recurrent tetany as the only manifestation of Gitelman′s syndrome, which is an unusual presentation. Potassium replacement with supplementation of other deficient ions led to satisfactory clinical and biochemical response.

  11. A review of stress concentration factors in tubular and non-tubular joints for design of offshore installations

    Directory of Open Access Journals (Sweden)

    Dikshant Singh Saini

    2016-09-01

    Full Text Available Tubular structures are widely used in offshore installations, trusses, high rise buildings, towers for wind turbines, ski-lift installations, lightning, road pole signals etc., owing to their excellent structural performance and attractive appearance. Stress concentration, especially in the welded joints of these structures, is an important design consideration particularly for fatigue design. In the context of tubular and non-tubular joints, this paper provides a review of the experimental and numerical studies that have been carried out so far to determine the stress concentration factor (SCF. Emphasis is also placed on the complexity of capturing different types of stresses in tubular/non-tubular joints for estimation of SCF. Present code provisions for evaluation of SCF are also discussed. Further, a few issues, which require significant research effort to advance our understanding and to improve the current design guidelines, have been identified.

  12. Detection of Acute Tubular Necrosis Using Blood Oxygenation Level-Dependent (BOLD MRI

    Directory of Open Access Journals (Sweden)

    Frederic Bauer

    2017-12-01

    Full Text Available Background/Aims: To date, there is no imaging technique to assess tubular function in vivo. Blood oxygen level-dependent magnetic resonance imaging (BOLD MRI measures tissue oxygenation based on the transverse relaxation rate (R2*. The present study investigates whether BOLD MRI can assess tubular function using a tubule-specific pharmacological maneuver. Methods: Cross sectional study with 28 participants including 9 subjects with ATN-induced acute kidney injury (AKI, 9 healthy controls, and 10 subjects with nephron sparing tumor resection (NSS with clamping of the renal artery serving as a model of ischemia/reperfusion (I/R-induced subclinical ATN (median clamping time 15 min, no significant decrease of eGFR, p=0.14. BOLD MRI was performed before and 5, 7, and 10 min after intravenous administration of 40 mg furosemide. Results: Urinary neutrophil gelatinase-associated lipocalin was significantly higher in ATN-induced AKI and NSS subjects than in healthy controls (p=0.03 and p=0.01, respectively. Before administration of furosemide, absolute medullary R2*, cortical R2*, and medullary/cortical R2* ratio did not significantly differ between ATN-induced AKI vs. healthy controls and between NSS-I/R vs. contralateral healthy kidneys (p>0.05 each. Furosemide led to a significant decrease in the medullary and cortical R2* of healthy subjects and NSS contralateral kidneys (p<0.05 each, whereas there was no significant change of R2* in ATN-induced AKI and the NSS-I/R kidneys (p>0.05 each. Conclusion: BOLD-MRI is able to detect even mild tubular injury but necessitates a tubule-specific pharmacological maneuver, e.g. blocking the Na+-K+-2Cl- transporter by furosemide.

  13. Oxygen transport properties of tubular Ce0.9Gd0.1O1.95-La0.6Sr0.4FeO3−d composite asymmetric oxygen permeation membranes supported on magnesium oxide

    DEFF Research Database (Denmark)

    Ovtar, Simona; Gurauskis, Jonas; Bjørnetun Haugen, Astri

    2017-01-01

    The oxygen permeation through dense Ce0.9Gd0.1O1.95-La0.6Sr0.4FeO3−d  dual-phase composite asymmetric membranes supported on a porous MgO tube was studied. The membranes were prepared by thermoplastic extrusion, dip coating, co-sintering and infiltration of a catalyst. Oxygen permeation measureme...

  14. Tubular adenoma of the urinary tract: a newly described entity.

    Science.gov (United States)

    Kao, Chia-Sui; Epstein, Jonathan I

    2013-09-01

    Tubular adenomas in the urinary tract with the same appearance as those in the gastrointestinal tract have not yet been described in the literature. We herein report 4 cases of tubular adenomas in the urinary tract encountered within our consult practice. This lesion was defined by the presence of a collection of small round tubular glands with intestinal-type epithelium showing moderate dysplasia, identical to the histology of tubular adenomas in the intestinal tract. Patients ranged in age from 37 to 63 years (mean, 45 years), with 3 of the 4 being male (male-to-female ratio, 3:1). The locations were urinary bladder, prostatic urethra and ureter with hematuria, polyps, and obstructive mass as their presentations, respectively. One lesion was large measuring 1.4 cm associated with pseudoinvasion as well as invasive adenocarcinoma. Immunohistochemically, the tubular adenomas stained positive for CDX2 and CK20, while negative for GATA3 and CK7. One case showed positive nuclear β-catenin staining. Tubular adenoma of the urinary tract is a rare lesion, and recognition of this entity will encourage further reports and help to better understand the relation of tubular adenoma to concurrent and subsequent urinary tract malignancies. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Transverse correlation: An efficient transverse flow estimator - initial results

    DEFF Research Database (Denmark)

    Holfort, Iben Kraglund; Henze, Lasse; Kortbek, Jacob

    2008-01-01

    Color flow mapping has become an important clinical tool, for diagnosing a wide range of vascular diseases. Only the velocity component along the ultrasonic beam is estimated, so to find the actual blood velocity, the beam to flow angle has to be known. Because of the unpredictable nature...... for estimating the transverse velocity component. The method measures the transverse velocity component by estimating the transit time of the blood between two parallel lines beamformed in receive. The method has been investigated using simulations performed with Field II. Using 15 emissions per estimate...

  16. Investigation of Transverse Oscillation Method

    DEFF Research Database (Denmark)

    Udesen, Jesper; Jensen, Jørgen Arendt

    2006-01-01

    Conventional ultrasound scanners can only display the axial component of the blood velocity vector, which is a significant limitation when vessels nearly parallel to the skin surface are scanned. The transverse oscillation method (TO) overcomes this limitation by introducing a transverse oscillat......Conventional ultrasound scanners can only display the axial component of the blood velocity vector, which is a significant limitation when vessels nearly parallel to the skin surface are scanned. The transverse oscillation method (TO) overcomes this limitation by introducing a transverse...... II. A virtual linear array transducer with center frequency 7 MHz and 128 active elements is created, and a virtual blood vessel of radius 6.4 mm is simulated. The performance of the TO method is found around an initial point in the parameter space. The parameters varied are: flow angle, transmit...... focus depth, receive apodization, pulse length, transverse wave length, number of emissions, signal to noise ratio, and type of echo canceling filter used. Using the experimental scanner RASMUS, the performance of the TO method is evaluated. An experimental flowrig is used to create laminar parabolic...

  17. Generation of induced pluripotent stem cells from renal tubular cells of a patient with Alport syndrome

    Directory of Open Access Journals (Sweden)

    Chen WB

    2015-08-01

    Full Text Available Wenbiao Chen,1,* Jianrong Huang,2,* Xiangqi Yu,1 Xiaocong Lin,1 Yong Dai11The Clinical Medical Research Center, Second Clinical Medical College of Jinan University, Shenzhen People's Hospital, 2Department of Hemodialysis, The Third People's Hospital of Shenzhen, Shenzhen, Guangdong, 3Institute of Biochemistry and Molecular Biology, Guangdong Medical College, Zhanjiang, People's Republic of China *These authors contributed equally to this workAbstract: Alport syndrome (AS is a hereditary disease that leads to kidney failure and is caused by mutations in the COL4A3, COL4A4, and COL4A5 genes that lead to the absence of collagen α3α4α5 (IV networks in the mature kidney glomerular basement membrane. Approximately 80% of AS is X-linked because of mutations in COL4A5, the gene encoding the alpha 5 chain of type IV collagen. To investigate the pathogenesis of AS at the genetic level, we generated induced pluripotent stem cells (iPSCs from renal tubular cells of a patient with AS. The successful iPSC generation laid the foundation to master the repair of the COL4A5 gene and to evaluate the differentiation of iPSC into Sertoli cells and the accompanying epigenetic changes at each stage. The generation of iPSCs from AS patients not only confirms that iPSCs could be generated from renal tubular cells, but also provides a novel type of genetic therapy for AS patients. In this study, we generated iPSCs from renal tubular cells via ectopic expression of four transcription factors (Oct4, Sox2, c-myc, and Klf4. According to the human embryonic stem cell (hESC charter, iPSC formation was confirmed by comparatively analyzing hESC markers via colony morphology, immunohistochemistry, qRT-PCR, flow cytometry, gene expression profiling of the three germ layers, and karyotyping. Our results demonstrated that iPSCs were similar to hESCs with regard to morphology, proliferation, hESC-specific surface marker expression, and differentiation into the cell types of the

  18. Single transverse mode protein laser

    Science.gov (United States)

    Dogru, Itir Bakis; Min, Kyungtaek; Umar, Muhammad; Bahmani Jalali, Houman; Begar, Efe; Conkar, Deniz; Firat Karalar, Elif Nur; Kim, Sunghwan; Nizamoglu, Sedat

    2017-12-01

    Here, we report a single transverse mode distributed feedback (DFB) protein laser. The gain medium that is composed of enhanced green fluorescent protein in a silk fibroin matrix yields a waveguiding gain layer on a DFB resonator. The thin TiO2 layer on the quartz grating improves optical feedback due to the increased effective refractive index. The protein laser shows a single transverse mode lasing at the wavelength of 520 nm with the threshold level of 92.1 μJ/ mm2.

  19. Elastic Deployable Composite Tubular Roll-Out Boom, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — DSS's innovative Elastic Deployable Composite Tubular Roll-Out Boom will provide revolutionary performance when compared to conventional state-of-the-art...

  20. Fatigue Life of High-Strength Steel Offshore Tubular Joints

    DEFF Research Database (Denmark)

    Petersen, Rasmus Ingomar; Agerskov, Henning; Lopez Martinez, Luis

    1996-01-01

    In the present investigation, the fatigue life of tubular joints in offshore steel structures is studied. Two test series on full-scale tubular joints have been carried through. One series was on joints in conventional offshore structural steel, and the other series was on joints in high......-strength steel with a yield stress of 820-830 MPa and with high weldability and toughness properties. The test specimens of both series had the same geometry. The present report concentrates on the results obtained in the investigation on the high-strength steel tubular joints.The test specimens were fabricated...... amplitude fatigue test results showed shorter fatigue lives in variable amplitude loading than should be expected from the linear fatigue damage accumulation formula. Furthermore, the fatigue tests on high-strength steel tubular joints showed slightly longer fatigue lives than those obtained...

  1. Rapidly Extending And Contracting Tubular (REACT) Boom System Development

    Data.gov (United States)

    National Aeronautics and Space Administration — This project aims to create a prototype retractable, reel stored, tubular boom system with the capability to hold a magnetically sensitive science instrument or...

  2. Solar Heating Systems with Evacuated Tubular Solar Collector

    DEFF Research Database (Denmark)

    Qin, Lin; Furbo, Simon

    1998-01-01

    Recently different designed evacuated tubular solar collectors were introduced on the market by different Chinese companies. In the present study, investigations on the performance of four different Chinese evacuated tubular collectors and of solar heating systems using these collectors were...... carried out, employing both laboratory test and theoretical calculations. The collectors were tested in a small solar domestic hot water (SDHW) system in a laboratory test facility under realistic conditions. The yearly thermal performance of solar heating systems with these evacuated tubular collectors......, as well as with normal flat-plate collectors was calculated under Danish weather conditions. It is found that, for small SDHW systems with a combi tank design, an increase of 25% -55% net utilized solar energy can be achieved by using these evacuated tubular collectors instead of normal flat...

  3. Scenario analysis of large scale algae production in tubular photobioreactors

    NARCIS (Netherlands)

    Slegers, P.M.; Beveren, van P.J.M.; Wijffels, R.H.; Straten, van G.; Boxtel, van A.J.B.

    2013-01-01

    Microalgae productivity in tubular photobioreactors depends on algae species, location, tube diameter, biomass concentration, distance between tubes and for vertically stacked systems, the number of horizontal tubes per stack. A simulation model for horizontal and vertically stacked horizontal

  4. Genetics Home Reference: renal tubular acidosis with deafness

    Science.gov (United States)

    ... Disorders and Deafness Health Topic: Hearing Problems in Children Health Topic: Kidney Diseases Genetic and Rare Diseases Information Center (1 link) Renal tubular acidosis with deafness Additional NIH Resources (2 ...

  5. Muscle MR imaging in tubular aggregate myopathy.

    Directory of Open Access Journals (Sweden)

    Valeria Beltrame

    Full Text Available PURPOSE: To evaluate with Magnetic Resonance (MR the degree of fatty replacement and edematous involvement in skeletal muscles in patients with Tubular Aggregate Myopathy (TAM. To asses the inter-observer agreement in evaluating muscle involvement and the symmetry index of fatty replacement. MATERIALS AND METHODS: 13 patients were evaluated by MR to ascertain the degree of fatty replacement (T1W sequences according to Mercuri's scale, and edema score (STIR sequences according to extent and site. RESULTS: Fatty replacement mainly affects the posterior superficial compartment of the leg; the anterior compartment is generally spared. Edema was generally poor and almost only in the superficial compartment of the leg. The inter-observer agreement is very good with a Krippendorff's coefficient >0.9. Data show a total symmetry in the muscular replacement (McNemar-Bowker test with p = 1. CONCLUSIONS: MR reveals characteristic muscular involvement, and is a reproducible technique for evaluation of TAM. There may also be a characteristic involvement of the long and short heads of the biceps femoris. It is useful for aimed biopsies, diagnostic hypotheses and evaluation of disease progression.

  6. The Fourier transform of tubular densities

    KAUST Repository

    Prior, C B

    2012-05-18

    We consider the Fourier transform of tubular volume densities, with arbitrary axial geometry and (possibly) twisted internal structure. This density can be used to represent, among others, magnetic flux or the electron density of biopolymer molecules. We consider tubes of both finite radii and unrestricted radius. When there is overlap of the tube structure the net density is calculated using the super-position principle. The Fourier transform of this density is composed of two expressions, one for which the radius of the tube is less than the curvature of the axis and one for which the radius is greater (which must have density overlap). This expression can accommodate an asymmetric density distribution and a tube structure which has non-uniform twisting. In addition we give several simpler expressions for isotropic densities, densities of finite radius, densities which decay at a rate sufficient to minimize local overlap and finally individual surfaces of the tube manifold. These simplified cases can often be expressed as arclength integrals and can be evaluated using a system of first-order ODEs. © 2012 IOP Publishing Ltd.

  7. Excimer Lasers With Capacitively Excited Tubular Discharges

    Science.gov (United States)

    Eichler, Hans J.; Herweg, Helmut; de la Rosa, Jose

    1989-04-01

    The excitation of excimer lasers in tubular discharges results in simple and compact devices needing no preionization. Optical output energies are in the millijoule range. We investigated XeF, KrF and ArF lasers for various operating conditions. The lasers consist of capillary glass tubes with two internal electrodes at the ends and an aluminium-foil wrapped around the tube as capacitive electrode. A maximum output energy of 0.3 mJ has been achieved for the XeF laser. The good quality of the discharge is indicated by the observation of spontaneous mode locking. The detailed study of the discharge for different polarities of the electrodes has shown that efficient operation with a high gas lifetime can be obtained by a purely capacitively excited discharge. A gas lifetime of about 10,000 pulses for 3 litres gas mixture has been observed. Using a two stage Marx generator to generate 100 kV excitation voltage a maximum output energy of 0.7 mJ was obtained for a gas mixture of Kr, F2 and He with an efficiency of 0.17%. The KrF laser operates also without the buffer gas. Laser action in ArF has been achieved with 15 μJ pulse energy and 10 ns duration.

  8. A tubular electrode for radiofrequency ablation therapy

    KAUST Repository

    Antunes, Carlos Lemos Lemos Lemos

    2012-07-06

    Purpose – Due to its good mechanical and biocompatibility characteristics, nitinol SEMS is a popular endoprothesis used for relieving stricture problems in hollow organs due to carcinomas. Besides its mechanical application, SEMS can be regarded as well as potential electrode for performing RF ablation therapy on the tumor. The purpose of this work is to perform numerical and experimental analyses in order to characterize the lesion volume induced in biological tissue using this kind of tubular electrode. Design/methodology/approach – Data concerning electrical conductivity and dimension of the damaged tissue after RF ablation procedure were obtained from ex vivo samples. Next, numerical models using 3D finite element method were obtained reassembling the conditions considered at experimentation setup and results were compared. Findings – Numerical and experimental results show that a regular volume of damaged tissue can be obtained considering this type of electrode. Also, results obtained from numerical simulation are close to those obtained by experimentation. Originality/value – SEMSs, commonly used as devices to minimize obstruction problems due to the growth of tumors, may still be considered as an active electrode for RF ablation procedures. A method considering this observation is presented in this paper. Also, numerical simulation can be regarded in this case as a tool for determining the lesion volume.

  9. Tubular heart valves from decellularized engineered tissue.

    Science.gov (United States)

    Syedain, Zeeshan H; Meier, Lee A; Reimer, Jay M; Tranquillo, Robert T

    2013-12-01

    A novel tissue-engineered heart valve (TEHV) was fabricated from a decellularized tissue tube mounted on a frame with three struts, which upon back-pressure cause the tube to collapse into three coapting "leaflets." The tissue was completely biological, fabricated from ovine fibroblasts dispersed within a fibrin gel, compacted into a circumferentially aligned tube on a mandrel, and matured using a bioreactor system that applied cyclic distension. Following decellularization, the resulting tissue possessed tensile mechanical properties, mechanical anisotropy, and collagen content that were comparable to native pulmonary valve leaflets. When mounted on a custom frame and tested within a pulse duplicator system, the tubular TEHV displayed excellent function under both aortic and pulmonary conditions, with minimal regurgitant fractions and transvalvular pressure gradients at peak systole, as well as well as effective orifice areas exceeding those of current commercially available valve replacements. Short-term fatigue testing of one million cycles with pulmonary pressure gradients was conducted without significant change in mechanical properties and no observable macroscopic tissue deterioration. This study presents an attractive potential alternative to current tissue valve replacements due to its avoidance of chemical fixation and utilization of a tissue conducive to recellularization by host cell infiltration.

  10. Clinical profile of distal renal tubular acidosis

    Directory of Open Access Journals (Sweden)

    Ratan Jha

    2011-01-01

    Full Text Available To determine the clinical profile and progression of renal dysfunction in distal renal tubular acidosis (dRTA, we retrospectively studied 96 consecutive cases of dRTA diagnosed at our center. Patients with unexplained metabolic bone disease, short stature, hypokalemia, re-current renal stones, chronic obstructive uropathy or any primary autoimmune condition known to cause dRTA were screened. Distal RTA was diagnosed on the basis of systemic metabolic acidosis with urine pH >5.5 and positive urine anion gap. In those patients who had fasting urine pH >5.5 with normal baseline systemic pH and bicarbonate levels (incomplete RTA, acid load test with ammonium chloride was done. A cause of dRTA could be established in 53 (54% patients. Urological defect in children (22/44 and autoimmune disease in adults (11/52 were the commonest causes. Hypokalemic paralysis, proximal muscle weakness and voiding difficulty were the common modes of presentation. Doubling of serum creatinine during the study period was noted in 13 out of 27 patients who had GFR 60 mL/min (P <0.005. In conclusion, urological disorders were the commonest cause of dRTA in children while autoimmune disorders were the commonest asso-ciation in adults. Worse baseline renal function, longer duration of disease and greater frequency of nephrolithiasis/nephrocalcinosis and urological disorders were noted in those who had wor-sening of renal dysfunction during the study period.

  11. Residual stress effects in tubular K-joints crack growth

    OpenAIRE

    Acevedo, Claire; Nussbaumer, Alain

    2010-01-01

    Seeking light and transparent bridge designs, engineers and architects have found an efficient and artistic way to fulfill their requirements: steel tubular bridges. Like any other welded structure, the joints of this kind of bridge suffer from high tensile weld residual stresses. Combined with high stress concentrations, tensile residual stress is a relevant factor in fatigue crack development. Therefore, an experimental study has been carried out on tubular joints in order to characterize ...

  12. Electrolyte composition of renal tubular cells in gentamicin nephrotoxicity

    International Nuclear Information System (INIS)

    Matsuda, O.; Beck, F.X.; Doerge, A.T.; Thurau, K.

    1988-01-01

    The effect of long-term gentamicin administration on sodium, potassium, chloride and phosphorus concentrations was studied in individual rat renal tubular cells using electron microprobe analysis. Histological damage was apparent only in proximal tubular cells. The extent of damage was only mild after 7 days of gentamicin administration (60 mg/kg body wt/day) but much more pronounced after 10 days. GFR showed a progressive decline during gentamicin treatment. In non-necrotic proximal tubular cells, sodium was increased from 14.6 +/- 0.3 (mean +/- SEM) in controls to 20.6 +/- 0.4 after 7 and 22.0 +/- 0.8 mmol/kg wet wt after 10 days of gentamicin administration. Chloride concentration was higher only after 10 days (20.6 +/- 0.6 vs. 17.3 +/- 0.2 mmol/kg wet wt). Both cell potassium and phosphorus concentrations were diminished by 6 and 15, and by 8 and 25 mmol/kg wet wt after 7 and 10 days of treatment, respectively. In contrast, no major alterations in distal tubular cell electrolyte concentrations could be observed after either 7 or 10 days of gentamicin administration. As in proximal tubular cells, distal tubular cell phosphorus concentrations were, however, lowered by gentamicin treatment. These results clearly indicate that gentamicin exerts its main effect on proximal tubular cells. Decreased potassium and increased sodium and chloride concentrations were observed in proximal tubular cells exhibiting only mild histological damage prior to the onset of advanced tissue injury. Necrotic cells, on the other hand, showed widely variable intracellular electrolyte concentration patterns

  13. Transverse permeability of woven fabrics

    NARCIS (Netherlands)

    Grouve, Wouter Johannes Bernardus; Akkerman, Remko; Loendersloot, Richard; van den Berg, S.

    2008-01-01

    The transverse permeability is an essential input in describing the consolidation process of CETEX® laminates. A two-dimensional, finite difference based, Stokes flow solver has been developed to determine the mesoscopic permeability of arbitrary fabric structures. The use of a multigrid solver

  14. OXYGEN TRANSPORT CERAMIC MEMBRANES

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

    2003-01-01

    In the present quarter, the possibility of using a more complex interfacial engineering approach to the development of reliable and stable oxygen transport perovskite ceramic membranes/metal seals is discussed. Experiments are presented and ceramic/metal interactions are characterized. Crack growth and fracture toughness of the membrane in the reducing conditions are also discussed. Future work regarding this approach is proposed are evaluated for strength and fracture in oxygen gradient conditions. Oxygen gradients are created in tubular membranes by insulating the inner surface from the reducing environment by platinum foils. Fracture in these test conditions is observed to have a gradient in trans and inter-granular fracture as opposed to pure trans-granular fracture observed in homogeneous conditions. Fracture gradients are reasoned to be due to oxygen gradient set up in the membrane, variation in stoichiometry across the thickness and due to varying decomposition of the parent perovskite. The studies are useful in predicting fracture criterion in actual reactor conditions and in understanding the initial evolution of fracture processes.

  15. Reorganization of the Endosomal System in Salmonella-Infected Cells: The Ultrastructure of Salmonella-Induced Tubular Compartments

    Science.gov (United States)

    Krieger, Viktoria; Liebl, David; Zhang, Yuying; Rajashekar, Roopa; Chlanda, Petr; Giesker, Katrin; Chikkaballi, Deepak; Hensel, Michael

    2014-01-01

    During the intracellular life of Salmonella enterica, a unique membrane-bound compartment termed Salmonella-containing vacuole, or SCV, is formed. By means of translocated effector proteins, intracellular Salmonella also induce the formation of extensive, highly dynamic membrane tubules termed Salmonella-induced filaments or SIF. Here we report the first detailed ultrastructural analyses of the SCV and SIF by electron microscopy (EM), EM tomography and live cell correlative light and electron microscopy (CLEM). We found that a subset of SIF is composed of double membranes that enclose portions of host cell cytosol and cytoskeletal filaments within its inner lumen. Despite some morphological similarities, we found that the formation of SIF double membranes is independent from autophagy and requires the function of the effector proteins SseF and SseG. The lumen of SIF network is accessible to various types of endocytosed material and our CLEM analysis of double membrane SIF demonstrated that fluid phase markers accumulate only between the inner and outer membrane of these structures, a space continual with endosomal lumen. Our work reveals how manipulation of the endosomal membrane system by an intracellular pathogen results in a unique tubular membrane compartmentalization of the host cell, generating a shielded niche permissive for intracellular proliferation of Salmonella. PMID:25254663

  16. Introduction to Transverse Beam Dynamics

    CERN Document Server

    Holzer, B.J.

    2014-01-01

    In this chapter we give an introduction to the transverse dynamics of the particles in a synchrotron or storage ring. The emphasis is more on qualitative understanding rather than on mathematical correctness, and a number of simulations are used to demonstrate the physical behaviour of the particles. Starting from the basic principles of how to design the geometry of the ring, we review the transverse motion of the particles, motivate the equation of motion, and show the solutions for typical storage ring elements. Following the usual treatment in the literature, we present a second way to describe the particle beam, using the concept of the emittance of the particle ensemble and the beta function, which reflects the overall focusing properties of the ring. The adiabatic shrinking due to Liouville's theorem is discussed as well as dispersive effects in the most simple case.

  17. Transversal Lines of the Debates

    Directory of Open Access Journals (Sweden)

    Yolanda Onghena

    1998-12-01

    Full Text Available The Transversal Lines of the Debates gathers for publication the presentations of the scholars invited to the seminar. In the papers, Yolanda Onghena observes that the evolution from the cultural to the inter-cultural travels along four axes: the relations between cultureand society; the processes of change within identity-based dynamics; the representations of the Other; and, interculturality. Throughout the presentations and subsequent debates, whenever the different participants referred to aspects of the cultural identity problematic--”angst”, “obsession”, “deficit”, manipulation”, and others, these same participants in the Transversal Lines of the Debates also showed that, in certain areas, an optimistic viewpoint is not out of the question.

  18. TRANSVERSALITY AND INTERDISCIPLINARY DISCUSSION IN ...

    African Journals Online (AJOL)

    2010-07-19

    Jul 19, 2010 ... e o lo g ic a l S tu d ie s http://www.hts.org.za. HTS. Original Research. A rtic le #. 9. 1. 0. (page number not for citation purposes). TRANSVERSALITY ... mentorship. An interview with a mentor and mentee was used as a local, real narrative in the process. In the final section, the author reflected upon his own ...

  19. Stereotactic minimally invasive tubular retractor system for deep brain lesions.

    Science.gov (United States)

    Greenfield, Jeffrey P; Cobb, William S; Tsouris, A John; Schwartz, Theodore H

    2008-10-01

    Deep-seated supratentorial intraparenchymal and intraventricular brain lesions can be difficult to access without causing significant trauma to the overlying cortex and intervening white matter tracts. Traditional brain retractors use multiple blades, which do not exert pressure in an equally distributed fashion. Tubular retractors offer an advantage. Although a commercially available frame-based tubular retractor system is on the market (COMPASS; Compass, Inc., Rochester, MN), we modified existing off-the-shelf equipment at our institution into a frameless tubular brain retractor. We used 14- to 22-mm METRx (Medtronic, Minneapolis, MN) tubular retractors in combination with a frameless stereotactic navigation system to remove 10 deep lesions. Histological findings included 6 periventricular metastases, 1 insular glioblastoma multiforme, 1 periventricular glioblastoma multiforme, 1 intraventricular meningioma, and 1 hippocampal cavernous malformation. Radiographic gross total resection was achieved in all patients. One patient experienced a transient worsening of an existing preoperative Wernicke's aphasia; otherwise, there were no intra- or postoperative complications. One patient with radiographic gross total resection of a metastatic lesion experienced a local recurrence of disease, requiring stereotactic radiosurgery. A frameless stereotactic tubular retractor system for deep brain lesions can be assembled with equipment already available at many institutions. Use of this system can decrease incision and craniotomy size, decrease retractor-induced trauma to overlying cortex, and help prevent damage to underlying white matter tracts.

  20. Proximal tubular dysfunction as an indicator of chronic graft dysfunction

    Directory of Open Access Journals (Sweden)

    N.O.S. Câmara

    2009-03-01

    Full Text Available New strategies are being devised to limit the impact of renal sclerosis on graft function. Individualization of immunosuppression, specifically the interruption of calcineurin-inhibitors has been tried in order to promote better graft survival once chronic graft dysfunction has been established. However, the long-term impact of these approaches is still not totally clear. Nevertheless, patients at higher risk for tubular atrophy and interstitial fibrosis (TA/IF development should be carefully monitored for tubular function as well as glomerular performance. Since tubular-interstitial impairment is an early event in TA/IF pathogenesis and associated with graft function, it seems reasonable that strategies directed at assessing tubular structural integrity and function would yield important functional and prognostic data. The measurement of small proteins in urine such as α-1-microglobulin, N-acetyl-beta-D-glucosaminidase, alpha/pi S-glutathione transferases, β-2 microglobulin, and retinol binding protein is associated with proximal tubular cell dysfunction. Therefore, its straightforward assessment could provide a powerful tool in patient monitoring and ongoing clinical assessment of graft function, ultimately helping to facilitate longer patient and graft survival associated with good graft function.

  1. Transversals in non-discrete groups

    Indian Academy of Sciences (India)

    Abstract. The concept of 'topological right transversal' is introduced to study right transversals in topological groups. Given any right quasigroup S with a Tychonoff topol- ogy T , it is proved that there exists a Hausdorff topological group in which S can be embedded algebraically and topologically as a right transversal of a ...

  2. Appraisal of transverse nasal groove: A study

    Directory of Open Access Journals (Sweden)

    Belagola D Sathyanarayana

    2012-01-01

    Full Text Available Background: Transverse nasal groove is a condition of cosmetic concern which awaits due recognition and has been widely described as a shallow groove that extends transversely over the dorsum of nose. However, we observed variations in the clinical presentations of this entity, hitherto undescribed in literature. Aims: We conducted a clinicoepidemiological study of transverse nasal lesions in patients attending our outpatient department. Methods: We conducted a prospective observational study. We screened all patients attending our out-patient department for presence of transverse nasal lesions, signs of any dermatosis and associated other skin conditions. Results: One hundred patients were recruited in the study. Females (80% predominated over males. Most patients were of 15-45 years age group (70%. Majority of the transverse nasal lesions were classical transverse nasal groove (39% and others included transverse nasal line (28%, strip (28%, ridge (4% and loop (1%. Seborrhoeic diathesis was the most common condition associated with transverse nasal lesion. Conclusions: Occurrence of transverse nasal line, strip, ridge and loop, in addition to classical transverse nasal groove implies that latter is actually a subset of transverse nasal lesions. Common association of this entity with seborrheic dermatitis, seborrhea and dandruff raises a possibility of whether transverse nasal lesion is a manifestation of seborrheic diathesis.

  3. Transversity of quarks in a nucleon

    Indian Academy of Sciences (India)

    The transversity distribution of quarks in a nucleon is one of the three fundamental distributions, that characterize nucleon's properties in hard scattering processes at leading twist (twist 2). It measures the distribution of quark transverse spin in a nucleon polarized transverse to its (infinite) momentum. It is a chiral-odd ...

  4. Polymyxin B Induces Apoptosis in Kidney Proximal Tubular Cells.

    Science.gov (United States)

    Azad, Mohammad A K; Finnin, Ben A; Poudyal, Anima; Davis, Kathryn; Li, Jinhua; Hill, Prue A; Nation, Roger L; Velkov, Tony; Li, Jian

    2013-09-01

    The nephrotoxicity of polymyxins is a major dose-limiting factor for treatment of infections caused by multidrug-resistant Gram-negative pathogens. The mechanism(s) of polymyxin-induced nephrotoxicity is not clear. This study aimed to investigate polymyxin B-induced apoptosis in kidney proximal tubular cells. Polymyxin B-induced apoptosis in NRK-52E cells was examined by caspase activation, DNA breakage, and translocation of membrane phosphatidylserine using Red-VAD-FMK [Val-Ala-Asp(O-Me) fluoromethyl ketone] staining, a terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL) assay, and double staining with annexin V-propidium iodide (PI). The concentration dependence (50% effective concentration [EC 50 ]) and time course for polymyxin B-induced apoptosis were measured in NRK-52E and HK-2 cells by fluorescence-activated cell sorting (FACS) with annexin V and PI. Polymyxin B-induced apoptosis in NRK-52E cells was confirmed by positive labeling from Red-VAD-FMK staining, TUNEL assay, and annexin V-PI double staining. The EC 50 (95% confidence interval [CI]) of polymyxin B for the NRK-52E cells was 1.05 (0.91 to 1.22) mM and was 0.35 (0.29 to 0.42) mM for HK-2 cells. At lower concentrations of polymyxin B, minimal apoptosis was observed, followed by a sharp rise in the apoptotic index at higher concentrations in both cell lines. After treatment of NRK-52E cells with 2.0 mM polymyxin B, the percentage of apoptotic cells (mean ± standard deviation [SD]) was 10.9% ± 4.69% at 6 h and reached plateau (>80%) at 24 h, whereas treatment with 0.5 mM polymyxin B for 24 h led to 93.6% ± 5.57% of HK-2 cells in apoptosis. Understanding the mechanism of polymyxin B-induced apoptosis will provide important information for discovering less nephrotoxic polymyxin-like lipopeptides. Copyright © 2013, American Society for Microbiology. All Rights Reserved.

  5. Construction and evaluation of PVC conventional and tubular tripelennamine-selective electrodes: their application in pharmaceutical preparations.

    Science.gov (United States)

    Lima, J L; Montenegro, M C; Sales, M G

    1996-06-01

    The construction and evaluation of tripelennamine conventionally-shaped ion-selective electrodes and tubular detectors for the determination of this compound in pharmaceutical formulations are described. Electrodes with conventional configuration have been constructed without an internal reference solution, using several types of immobilized ionic sensors in PVC. The different electrode membranes were prepared by using tripelennamine tetraphenylborate as ionic-exchanger, dissolved in 2-nitrophenyl octyl ether (type A), dibutylphthalate (type B) and bis-(2-ethylhexyl)sebacate (type C) as plasticizer solvents. The general working characteristics of the different types of conventional electrodes were evaluated in tripelennamine solutions, with adjusted ionic strength, showing a linear response in the concentration range of about 4 x 10(-5) - 1 x 10(-1) M and a slope near the theoretical value. The electrodes presented a fast response (> 20 s) and a high reproducibility (> or = 0.2 mV per day). The electrode selectivity in the presence of some interferents, such as sodium, potassium, lithium, ammonium, chlorpheniramine, diphenydramine, promethazine, meclizine and pentazocine, was good, particularly for those whose sensor membrane was prepared with tripelennamine tetraphenylborate dissolved in 2-nitrophenyl octyl ether (type A). Tubular detectors were also prepared using the same sensor membrane and were evaluated in a low-dispersion flow-injection manifold. Under these conditions the detectors presented response characteristics similar to those of the corresponding conventionally-shaped electrodes. The analysis of different pharmaceutical forms (creams, syrups and gels) gave good results with mean recoveries of 99.8-100.6% when the experiments were conducted by direct potentiometry and 99.9-100.4% where the same determinations were conducted by flow-injection analysis with tubular detectors.

  6. Alpha-enolase on apical surface of renal tubular epithelial cells serves as a calcium oxalate crystal receptor

    Science.gov (United States)

    Fong-Ngern, Kedsarin; Thongboonkerd, Visith

    2016-10-01

    To search for a strategy to prevent kidney stone formation/recurrence, this study addressed the role of α-enolase on apical membrane of renal tubular cells in mediating calcium oxalate monohydrate (COM) crystal adhesion. Its presence on apical membrane and in COM crystal-bound fraction was confirmed by Western blotting and immunofluorescence staining. Pretreating MDCK cells with anti-α-enolase antibody, not isotype-controlled IgG, dramatically reduced cell-crystal adhesion. Immunofluorescence staining also confirmed the direct binding of purified α-enolase to COM crystals at {121} > {100} > {010} crystal faces. Coating COM crystals with urinary proteins diminished the crystal binding capacity to cells and purified α-enolase. Moreover, α-enolase selectively bound to COM, not other crystals. Chemico-protein interactions analysis revealed that α-enolase interacted directly with Ca2+ and Mg2+. Incubating the cells with Mg2+ prior to cell-crystal adhesion assay significantly reduced crystal binding on the cell surface, whereas preincubation with EDTA, a divalent cation chelator, completely abolished Mg2+ effect, indicating that COM and Mg2+ competitively bind to α-enolase. Taken together, we successfully confirmed the role of α-enolase as a COM crystal receptor to mediate COM crystal adhesion at apical membrane of renal tubular cells. It may also serve as a target for stone prevention by blocking cell-crystal adhesion and stone nidus formation.

  7. A Model of Direct Contact Membrane Distillation of Black Currant Juice

    DEFF Research Database (Denmark)

    Jensen, Morten Busch; Christensen, Knud Villy; Andrésen, René

    2011-01-01

    A numerical model to describe a direct contact membrane distillation proces has been developed. Said model is based on the Dusty Gas model and shell mass and energy balances over a tubular membrane module.  "The solution is applicable to laminar, incompressible and continuous flow in shell......-side spacing of tubular-type unit."  Turtuosity and porosity are characteristics of the membrane in use and have been estimated base don eksperimental studies on destillation of pure water. The fitted model shows a good fit to experimental data obtained by destillation of black currant juice....

  8. Tailoring of porosity of yttria-stabilized zirconia tubes as supports for oxygen separation membranes

    DEFF Research Database (Denmark)

    Bjørnetun Haugen, Astri; Kothanda Ramachandran, Dhavanesan; Gurauskis, Jonas

    Pure oxygen gas supplied by ceramic oxygen transport membranes can facilitate reduced CO2 emissions through more efficient gasification processes and CO2 capture and storage. Tubular membranes have some advantages compared to planar membranes, such as better resistance to thermal gradients and more...... straightforward sealing. The active oxygen separation layer in the membrane should be as thin as possible and therefore supported on a highly porous tubular substrate. In this work tubular porous supports of yttria-stabilized zirconia have been manufactured using thermoplastic extrusion. Two types of poreformers...... exceeding 55 % and gas permeabilities close to 10-14 m2 could be produced, demonstrating that thermoplastic extrusion is suitable for fabrication of porous and permeable tubes....

  9. IgG from amyotrophic lateral sclerosis affects tubular calcium channels of skeletal muscle.

    Science.gov (United States)

    Delbono, O; García, J; Appel, S H; Stefani, E

    1991-06-01

    Amyotrophic lateral sclerosis (ALS) is a devastating human disease of upper and lower motoneurons. We studied the action of the immunoglobulin G (IgG) from ALS and disease control patients on dihydropyridine (DHP)-sensitive Ca2+ channels in single mammalian skeletal muscle fibers with the double Vaseline gap technique. The peak of the Ca2+ current (ICa) and the charge movement were reduced when the fibers were incubated in ALS IgG. These effects were lost when the IgG was boiled or adsorbed with skeletal tubular membranes. ALS IgG reduced skeletal muscle ICa in a similar fashion as nifedipine; the ICa blockade was voltage dependent, and the associated charge movement was reduced. These observations suggest that IgG from ALS patients reacts with the skeletal muscle DHP-sensitive Ca2+ channels or some associated regulatory moiety.

  10. Mathematical models for tubular structures in the family of Papovaviridae.

    Science.gov (United States)

    Twarock, R

    2005-09-01

    An important part of a virus is its protein shell, called the viral capsid, that protects the viral genome. While the viral capsids of viruses in the family of Papovaviridae are usually spherical, their protein building blocks are known to assemble also as tubular structures [Kiselev, N.A., Klug, A., 1969. J. Mol. Biol. 40, 155]. In Twarock [2004. J. Theor. Biol. 226, 477] Viral Tiling Theory has been introduced for the structural description of the protein stoichiometry of the spherical capsids in this family. This approach is extended here to the tubular case and is used to classify the surface lattices of tubular structures in the family of Papovaviridae. The predictions of the theory are compared with the experimental results in Kiselev and Klug [1969. J. Mol. Biol. 40, 155].

  11. Power generation characteristics of tubular type SOFC by wet process

    Energy Technology Data Exchange (ETDEWEB)

    Tajiri, H.; Nakayama, T. [Kyushu Electric Power Company, Inc., Fukuoka (Japan); Kuroishi, M. [TOTO Ltd., Kanagawa (Japan)] [and others

    1996-12-31

    The development of a practical solid oxide fuel cell requires improvement of a cell performance and a cell manufacturing technology suitable for the mass production. In particular tubular type SOFC is thought to be superior in its reliability because its configuration can avoid the high temperature sealing and reduce the thermal stress resulting from the contact between cells. The authors have fabricated a tubular cell with an air electrode support by a wet processing technique, which is suitable for mass production in improving a power density. To enhance the power output of the module, the Integrated Tubular-Type (ITT) cell has been developed. This paper reports the performance of the single cells with various active anode areas and the bundle with series-connected 9-ITT cells with an active anode area of 840 cm{sup 2}.

  12. Effect of corrosion on the buckling capacity of tubular members

    Science.gov (United States)

    Øyasæter, F. H.; Aeran, A.; Siriwardane, S. C.; Mikkelsen, O.

    2017-12-01

    Offshore installations are subjected to harsh marine environment and often have damages from corrosion. Several experimental and numerical studies were performed in the past to estimate buckling capacity of corroded tubular members. However, these studies were either based on limited experimental tests or numerical analyses of few cases resulting in semi-empirical relations. Also, there are no guidelines and recommendations in the currently available design standards. To fulfil this research gap, a new formula is proposed to estimate the residual strength of tubular members considering corrosion and initial geometrical imperfections. The proposed formula is verified with results from finite element analyses performed on several members and for varying corrosion patch parameters. The members are selected to represent the most relevant Eurocode buckling curve for tubular members. It is concluded that corrosion reduces the buckling capacity significantly and the proposed formula can be easily applied by practicing engineers without performing detailed numerical analyses.

  13. MODELING OF TUBULAR ELECTROCHEMICAL REACTOR FOR DYE REMOVAL

    Directory of Open Access Journals (Sweden)

    V. VIJAYAKUMAR

    2017-06-01

    Full Text Available The aim of the present investigation is to model a tubular electrochemical reactor for the treatment of synthetic dye wastewater. The tubular reactor was modeled and solved by finite difference method. For the model solution, the column was divided into 11 nodes in the axial direction and the variation in the radial direction has been neglected. An initial dye concentration of 200 mg L-1was taken in the reservoir. The reactor was operated in a batch with recirculation operation. Based on preliminary experiments all parameters have been optimized. The model simulation is compared with the experimental value and it is observed that the model fairly matches well with the experiment. The modeling of tubular electrochemical reactors for dye waste water treatment could be useful in the design and scale up of electrochemical process.

  14. Theoretical analysis of human muscle membrane behaviour in hypokalemic periodic paralysis

    NARCIS (Netherlands)

    Alberink, M.J.; Wallinga, W.; Wolters, H.; Wolters, Henk; Ypey, D.L.; Ypey, Dirk L.; Links, Thera P.; Boom, H.B.K.

    1995-01-01

    Computer simulations were performed to investigate the behavior of human muscle membrane with membrane defects supposed to be present in the muscular disease Hypokalemic Periodic Paralysis (HOPP). The model used for simulation was a Hodgkin-Huxley model. The T-tubular system was also incorporated.

  15. Membrane-associated cargo recycling by tubule-based endosomal sorting

    NARCIS (Netherlands)

    van Weering, J.R.T.; Cullen, P.J.

    2014-01-01

    The endosome system is a collection of organelles that sort membrane-associated proteins and lipids for lysosomal degradation or recycling back to their target organelle. Recycling cargo is captured in a network of membrane tubules emanating from endosomes where tubular carriers pinch off. These

  16. The origin of tubular lava stalactites and other related forms

    Directory of Open Access Journals (Sweden)

    Kevin Allred

    1998-01-01

    Full Text Available Tubular lava stalactites are often found in lava tubes. Field observations, sample analysis, and comparative studies indicate that these are segregations extruded during cooling from partially crystallized lava al about 1,070 - 1,000 °C. Retrograde boiling (gas pressure within the lava provides a mechanism to expel the interstitial liquid. In addition to tubular lava stalactites, a variety of other lava features can also result, such as lava helictites, lava coralloids, barnacle-like stretched lava, runners, runner channels, and some lava blisters and squeeze-ups.

  17. Water desalination by air-gap membrane distillation using meltblown polypropylene nanofiber membrane

    Science.gov (United States)

    Rosalam, S.; Chiam, C. K.; Widyaparamitha, S.; Chang, Y. W.; Lee, C. A.

    2016-06-01

    This paper presents a study of air gap membrane distillation (AGMD) using meltblown polypropylene (PP) nanofiber membrane to produce fresh water via desalination process. PP nanofiber membranes with the effective area 0.17 m2 are tested with NaCl solutions (0.5 - 4.0 wt.%) and seawater as the feed solutions (9400 - 64800 μS/cm) in a tubular membrane module. Results show that the flux decreases with increasing the membrane thickness from 547 to 784 μm. The flux increases with the feed flow rate and temperature difference across the membrane. The feed concentration affects the flux insignificantly. The AGMD system can reject the salts at least 96%. Water vapor permeation rate is relatively higher than solute permeation rate resulting in the conductivity value of permeate decreases when the corresponding flux increases. The AGMD system produces the fresh water (200 - 1520 μS/cm) that is suitable for drinking, fisheries or irrigation.

  18. Membrane dynamics

    DEFF Research Database (Denmark)

    Bendix, Pól Martin

    2015-01-01

    Current topics include membrane-protein interactions with regard to membrane deformation or curvature sensing by BAR domains. Also, we study the dynamics of membrane tubes of both cells and simple model membrane tubes. Finally, we study membrane phase behavior which has important implications...

  19. Noninterceptive transverse-beam measurements

    International Nuclear Information System (INIS)

    Chamberlin, D.D.; Minerbo, G.N.; Mottershead, C.T.

    1981-01-01

    Totally noninterceptive techniques for accurate measurement of transverse beam distributions are required for high-current continuous wave (cw) linacs, such as the Fusion Materials Irradiation Test (FMIT) accelerator. Sensors responding to visible radiation from beam interactions with residual gas and computer algorithms reconstructing spatial and phase space distributions have been implemented. This paper reports on early measurements of the beam from the injector of the prototype FMIT facility at Los Alamos. The first section indicates hardware setup and performance whereas the second section describes the data-processing software. The third section outlines the resultant measurements and further developments are discussed in the fourth section

  20. Entropy and transverse section reconstruction

    International Nuclear Information System (INIS)

    Gullberg, G.T.

    1976-01-01

    A new approach to the reconstruction of a transverse section using projection data from multiple views incorporates the concept of maximum entropy. The principle of maximizing information entropy embodies the assurance of minimizing bias or prejudice in the reconstruction. Using maximum entropy is a necessary condition for the reconstructed image. This entropy criterion is most appropriate for 3-D reconstruction of objects from projections where the system is underdetermined or the data are limited statistically. This is the case in nuclear medicine time limitations in patient studies do not yield sufficient projections

  1. Transverse and Longitudinal proximity effect

    Science.gov (United States)

    Jalan, Pryianka; Chand, Hum; Srianand, Raghunathan

    2018-04-01

    With close pairs (˜1.5arcmin) of quasars (QSOs), absorption in the spectra of a background quasar in the vicinity of a foreground quasar can be used to study the environment of the latter quasar at kpc-Mpc scales. For this we used a sample of 205 quasar pairs from the Sloan Digital Sky-Survey Data Release 12 (SDSS DR12) in the redshift range of 2.5 to 3.5 by studying their H I Ly-α absorption. We study the environment of QSOs both in the longitudinal as well as in the transverse direction by carrying out a statistical comparison of the Ly-α absorption lines in the quasar vicinity to that of the absorption lines caused by the inter-galactic medium (IGM). This comparison was done with IGM, matched in absorption redshift and signal-to-noise ratio (SNR) to that of the proximity region. In contrast to the measurements along the line-of-sight, the regions transverse to the quasars exhibit enhanced H I Ly-α absorption. This discrepancy can either be interpreted as due to an anisotropic emission from the quasars or as a consequence of their finite lifetime.

  2. Disturbances of the sarcoplasmic reticulum and transverse tubular system in 24-h electrostimulated fast-twitch skeletal muscle

    DEFF Research Database (Denmark)

    Frías, J A; Cadefau, J A; Prats, C

    2005-01-01

    Chronic low-frequency stimulation of rabbit tibialis anterior muscle over a 24-h period induces a conspicuous loss of isometric tension that is unrelated to muscle energy metabolism (J.A. Cadefau, J. Parra, R. Cusso, G. Heine, D. Pette, Responses of fatigable and fatigue-resistant fibres of rabbit...

  3. Graphene-coated hollow fiber membrane as the cathode in anaerobic electrochemical membrane bioreactors – Effect of configuration and applied voltage on performance and membrane fouling

    KAUST Repository

    Werner, Craig M.

    2015-12-22

    Electrically conductive, graphene-coated hollow-fiber porous membranes were used as cathodes in anaerobic electrochemical membrane bioreactors (AnEMBRs) operated at different applied voltages (0.7 V and 0.9 V) using a new rectangular reactor configuration, compared to a previous tubular design (0.7 V). The onset of biofouling was delayed and minimized in rectangular reactors operated at 0.9 V, compared to those at 0.7 V due to higher rates of hydrogen production. Maximum transmembrane pressures for the rectangular reactor were only 0.10 bar (0.7 V) or 0.05 bar (0.9 V) after 56 days of operation, compared to 0.46 bar (0.7 V) for the tubular reactor after 52 days. The thickness of the membrane biofouling layer was approximately 0.4 µm for rectangular reactors and 4 µm for the tubular reactor. Higher permeate quality (TSS = 0.05 mg/L) was achieved in the rectangular AnEMBR than the tubular AnEMBR (TSS = 17 mg/L), likely due to higher current densities that minimized the accumulation of cells in suspension. These results show that the new rectangular reactor design, which had increased rates of hydrogen production, successfully delayed the onset of cathode biofouling and improved reactor performance.

  4. Experimental investigation of transverse flow estimation using transverse oscillation

    DEFF Research Database (Denmark)

    Udesen, Jesper; Jensen, Jørgen Arendt

    2003-01-01

    Conventional ultrasound scanners can only display the blood velocity component parallel to the ultrasound beam. Introducing a laterally oscillating field gives signals from which the transverse velocity component can be estimated using 2:1 parallel receive beamformers. To yield the performance...... perpendicular to the ultrasound beam. The velocity profile of the blood is parabolic, and the speed of the blood in the center of the vessel is 1.1 m/s. An extended autocorrelation algorithm is used for velocity estimation for 310 trials, each containing 32 beamformed signals. The velocity can be estimated.......0% and the relative mean standard deviation is found to be 9.8%. With the Compuflow 1000 programmable flow pump a color flow mode image is produced of the experimental setup for a parabolic flow. Also the flow of the human femoralis is reproduced and it is found that the characteristics of the flow can be estimated....

  5. Versatility of tubularized incised plate urethroplasty in the ...

    African Journals Online (AJOL)

    Background: The outcomes of urethroplasty in the management of different types of hypospadias have continued to improve since the introduction of the tubularized incised plate (TIP) urethroplasty (Snodgrass method). The aim of this study was to evaluate the feasibility and applicability of TIP urethroplasty in the ...

  6. Tubularized Incised Plate (TIP) Urethroplasty: Extended Use in ...

    African Journals Online (AJOL)

    Objective: Recently, tubularized incised plate (TIP) urethroplasty (Snodgrass repair) has gained popularity for the primary repair of distal and proximal hypospadias. This study was carried out to evaluate TIP urethroplasty in the repair of failed and complicated hypospadias cases. Patients and Methods: This study was ...

  7. Tubularized incised plate urethroplasty repair in adult hypospadias ...

    African Journals Online (AJOL)

    Objective: Most studies published in the literature report on the results of tubularized incised plate urethroplasty (TIPU) for hypospadias repair in children. Hence, the objective of this study was to evaluate the results of TIPU repair in adults. Patients and methods: The records of 60 adult patients with primary hypospadias ...

  8. Renal pathophysiologic role of cortical tubular inclusion bodies.

    Science.gov (United States)

    Radi, Zaher A; Stewart, Zachary S; Grzemski, Felicity A; Bobrowski, Walter F

    2013-01-01

    Renal tubular inclusion bodies are rarely associated with drug administration. The authors describe the finding of renal cortical tubular intranuclear and intracytoplasmic inclusion bodies associated with the oral administration of a norepinephrine/serotonin reuptake inhibitor (NSRI) test article in Sprague-Dawley (SD) rats. Rats were given an NSRI daily for 4 weeks, and kidney histopathologic, ultrastructural pathology, and immunohistochemical examinations were performed. Round eosinophilic intranuclear inclusion bodies were observed histologically in the tubular epithelial cells of the renal cortex in male and female SD rats given the NSRI compound. No evidence of degeneration or necrosis was noted in the inclusion-containing renal cells. By ultrastructural pathology, inclusion bodies consisted of finely granular, amorphous, and uniformly stained nonmembrane-bound material. By immunohistochemistry, inclusion bodies stained positive for d-amino acid oxidase (DAO) protein. In addition, similar inclusion bodies were noted in the cytoplasmic tubular epithelial compartment by ultrastructural and immunohistochemical examination.  This is the first description of these renal inclusion bodies after an NSRI test article administration in SD rats. Such drug-induced renal inclusion bodies are rat-specific, do not represent an expression of nephrotoxicity, represent altered metabolism of d-amino acids, and are not relevant to human safety risk assessment.

  9. Tubularized incised plate technique for recurrent hypospadias: a ...

    African Journals Online (AJOL)

    Annals of Pediatric Surgery 2012, 8:80–85. Keywords: recurrent hypospadias, salvage hypospadias, tubularized incised plate. aDepartment of Surgery, Division of Pediatric and Plastic Surgery, Faculty of. Medicine, Suez Canal University, Ismailia and bDepartment of Surgery, Faculty of. Medicine, Menoufia University ...

  10. Predominant Tubular Interleukin-18 Expression in Polyomavirus-Associated Nephropathy

    NARCIS (Netherlands)

    Stokman, Geurt; Kers, Jesper; Yapici, Ünsal; Hoelbeek, Joris J.; Claessen, Nike; de Boer, Onno J.; Netea, Mihai G.; Hilbrands, Luuk; Bemelman, Fréderike J.; ten Berge, Ineke J. M.; Florquin, Sandrine

    2016-01-01

    Polyomavirus-associated nephropathy (PVAN) occurs in a significant percentage of renal transplant recipients, with BK virus reactivation as the main causative agent. PVAN leads to tubular damage and may result in allograft loss. In this study, we analyzed the antiviral immune response in PVAN.

  11. Albumin Is Recycled from the Primary Urine by Tubular Transcytosis

    Science.gov (United States)

    Tenten, Verena; Menzel, Sylvia; Kunter, Uta; Sicking, Eva-Maria; van Roeyen, Claudia R. C.; Sanden, Silja K.; Kaldenbach, Michaela; Boor, Peter; Fuss, Astrid; Uhlig, Sandra; Lanzmich, Regina; Willemsen, Brigith; Dijkman, Henry; Grepl, Martin; Wild, Klemens; Kriz, Wilhelm; Smeets, Bart; Floege, Jürgen

    2013-01-01

    Under physiologic conditions, significant amounts of plasma protein pass the renal filter and are reabsorbed by proximal tubular cells, but it is not clear whether the endocytosed protein, particularly albumin, is degraded in lysosomes or returned to the circulatory system intact. To resolve this question, a transgenic mouse with podocyte-specific expression of doxycycline-inducible tagged murine albumin was developed. To assess potential glomerular backfiltration, two types of albumin with different charges were expressed. On administration of doxycycline, podocytes expressed either of the two types of transgenic albumin, which were secreted into the primary filtrate and reabsorbed by proximal tubular cells, resulting in serum accumulation. Renal transplantation experiments confirmed that extrarenal transcription of transgenic albumin was unlikely to account for these results. Genetic deletion of the neonatal Fc receptor (FcRn), which rescues albumin and IgG from lysosomal degradation, abolished transcytosis of both types of transgenic albumin and IgG in proximal tubular cells. In summary, we provide evidence of a transcytosis within the kidney tubular system that protects albumin and IgG from lysosomal degradation, allowing these proteins to be recycled intact. PMID:23970123

  12. Distal Renal Tubular Acidosis, an Uncommonly diagnosed Cause of ...

    African Journals Online (AJOL)

    Five cases of distal renal tubular acidosis aged between 2½ weeks and 2½ months are described. The presenting features included lethargy, refusal to feed, high density of periodic respiration, vomiting and recurrent episodes of unexplained metabolic acidosis. A constant feature was failure to thrive despite caloric intakes ...

  13. Some asymptotic properties of functions holomorphic in tubular domains

    International Nuclear Information System (INIS)

    Zavialov, B.I.

    1988-10-01

    For the function holomorphic in curved tubular domain the connection between asymptotic behaviour of real part of its boundary value at a given point of base manifold and asymptotic behaviour of the whole function from the inside of this domain is studied. (author). 3 refs

  14. Hemodynamic and tubular changes induced by contrast media.

    Science.gov (United States)

    Caiazza, Antonella; Russo, Luigi; Sabbatini, Massimo; Russo, Domenico

    2014-01-01

    The incidence of acute kidney injury induced by contrast media (CI-AKI) is the third cause of AKI in hospitalized patients. Contrast media cause relevant alterations both in renal hemodynamics and in renal tubular cell function that lead to CI-AKI. The vasoconstriction of intrarenal vasculature is the main hemodynamic change induced by contrast media; the vasoconstriction is accompanied by a cascade of events leading to ischemia and reduction of glomerular filtration rate. Cytotoxicity of contrast media causes apoptosis of tubular cells with consequent formation of casts and worsening of ischemia. There is an interplay between the negative effects of contrast media on renal hemodynamics and on tubular cell function that leads to activation of renin-angiotensin system and increased production of reactive oxygen species (ROS) within the kidney. Production of ROS intensifies cellular hypoxia through endothelial dysfunction and alteration of mechanisms regulating tubular cells transport. The physiochemical characteristics of contrast media play a critical role in the incidence of CI-AKI. Guidelines suggest the use of either isoosmolar or low-osmolar contrast media rather than high-osmolar contrast media particularly in patients at increased risk of CI-AKI. Older age, presence of atherosclerosis, congestive heart failure, chronic renal disease, nephrotoxic drugs, and diuretics may multiply the risk of CI-AKI.

  15. Importance of early audiologic assessment in distal renal tubular acidosis

    Directory of Open Access Journals (Sweden)

    Elizabeth Norgett

    2010-12-01

    Full Text Available Anand P Swayamprakasam1, Elizabeth Stover1, Elizabeth Norgett1, Katherine G Blake-Palmer1, Michael J Cunningham2, Fiona E Karet11Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, UK; 2Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, MA, USAAbstract: Autosomal recessive distal renal tubular acidosis is usually a severe disease of childhood, often presenting as failure to thrive in infancy. It is often, but not always, accompanied by sensorineural hearing loss, the clinical severity and age of onset of which may be different from the other clinical features. Mutations in either ATP6V1B1 or ATP6V0A4 are the chief causes of primary distal renal tubular acidosis with or without hearing loss, although the loss is often milder in the latter. We describe a kindred with compound heterozygous alterations in ATP6V0A4, where hearing loss was formally diagnosed late in both siblings such that they missed early opportunities for hearing support. This kindred highlights the importance of routine audiologic assessments of all children with distal renal tubular acidosis, irrespective either of age at diagnosis or of which gene is mutated. In addition, when diagnostic genetic testing is undertaken, both genes should be screened irrespective of current hearing status. A strategy for this is outlined.Keywords: sensorineural hearing loss, renal tubular acidosis, recessive, genetics, mutation

  16. Finite element analysis of tubular joints in offshore structures ...

    African Journals Online (AJOL)

    ... representing a 2-D model of the joint between the brace and the chord walls. This was subsequently followed but finite element analysis of six tubular joints. A global analysis was initially undertaken, then the submodel analysis carried in the areas of stress concentration. Journal of Civil Engineering, JKUAT (2001) Vol 6, ...

  17. Start up of an industrial adiabatic tubular reactor

    NARCIS (Netherlands)

    Verwijs, J.W.; Verwijs, J.W.; van den Berg, Henderikus; Westerterp, K.R.

    1992-01-01

    The dynamic behaviour of an adiabatic tubular plant reactor during the startup is demonstrated, together with the impact of a feed-pump failure of one of the reactants. A dynamic model of the reactor system is presented, and the system response is calculated as a function of

  18. Urinary Markers of Tubular Injury in Early Diabetic Nephropathy

    Directory of Open Access Journals (Sweden)

    Temesgen Fiseha

    2016-01-01

    Full Text Available Diabetic nephropathy (DN is a common and serious complication of diabetes associated with adverse outcomes of renal failure, cardiovascular disease, and premature mortality. Early and accurate identification of DN is therefore of critical importance to improve patient outcomes. Albuminuria, a marker of glomerular involvement in early renal damage, cannot always detect early DN. Thus, more sensitive and specific markers in addition to albuminuria are needed to predict the early onset and progression of DN. Tubular injury, as shown by the detection of tubular injury markers in the urine, is a critical component of the early course of DN. These urinary tubular markers may increase in diabetic patients, even before diagnosis of microalbuminuria representing early markers of normoalbuminuric DN. In this review we summarized some new and important urinary markers of tubular injury, such as neutrophil gelatinase associated lipocalin (NGAL, kidney injury molecule-1 (KIM-1, liver-type fatty acid binding protein (L-FABP, N-acetyl-beta-glucosaminidase (NAG, alpha-1 microglobulin (A1M, beta 2-microglobulin (B2-M, and retinol binding protein (RBP associated with early DN.

  19. Characterization of Foam Catalysts as Packing for Tubular Reactors.

    Czech Academy of Sciences Publication Activity Database

    Lali, Farzad

    2016-01-01

    Roč. 105, JUL 2016 (2016), s. 1-9 ISSN 0255-2701 Institutional support: RVO:67985858 Keywords : overall mass transfer * foam catalyst * tubular reactor Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 2.234, year: 2016

  20. Phorbol esters inhibit gluconeogenesis in canine renal proximal tubular segments.

    Science.gov (United States)

    Rogers, S; Gavin, J R; Hammerman, M R

    1985-08-01

    Gluconeogenesis is a major metabolic function of the renal proximal tubular cell. To characterize the regulation of this process in proximal tubule, glucose production from gluconeogenic precursors was measured in proximal tubular segments prepared from dog kidney. Production of glucose was a linear function of time for up to 120 min of incubation at 37 degrees C under a variety of conditions. Lowering the pH of incubation media from 7.5 to 7.0 increased glucose synthesis. Production of glucose was inhibited by 3-mercaptopicolinate. Incubation of proximal tubular segments with insulin diminished synthesis of glucose. Incubation of segments with tumor-promoting phorbol esters, 12-O-tetradecanoylphorbol-13-acetate or phorbol 12,13-dibutyrate, resulted in decreased production of glucose. This effect was not observed following incubation with the inactive phorbol ester 4 alpha-phorbol. Changes in glucose synthesis could not be attributed to alterations in cell viability or in rates of glucose oxidation induced by experimental maneuvers. Our findings confirm the usefulness of proximal tubular segments for characterization of metabolic processes in this portion of the nephron. The experimental results are consistent with a role for protein kinase C in the control of gluconeogenesis in proximal tubule.

  1. Subanalytic Bundles and Tubular Neighbourhoods of Zero-Loci

    Indian Academy of Sciences (India)

    We introduce the natural and fairly general notion of a subanalytic bundle (with a finite dimensional vector space of sections) on a subanalytic subset of a real analytic manifold , and prove that when is compact, there is a Baire subset of sections in whose zero-loci in have tubular neighbourhoods, ...

  2. STEREOLOGICAL ESTIMATION OF TUBULAR LENGTH FROM THIN VERTICAL SECTIONS

    Directory of Open Access Journals (Sweden)

    Helle V Clausen

    2011-05-01

    Full Text Available In this study tubular structures are represented by stem villous arteries of the human placenta. The architecture of the vascular tree in the human placenta makes it appropriate to use vertical histological sections. Describing tubules, estimates of total length and diameter are informative. The aim of the study was to derive a new stereological estimator of the total length of circular tubules observed in thin vertical sections. Design: Dual perfusion fixed human placentas. Systematic, uniformly random sampling of vertical sections. Five-μm-sections were stained by haematoxylin and eosin (H&E and the vertical axis was identified in all sections. A test system with cycloid test lines was used. Since tubular surface area is proportional to length and diameter, S ∝ πdL, surface-weightening is equivalent to diameter×lengthweightening. As each diameter (extra weight is known, one may eliminate the diameter-weightening by computing the harmonic mean diameter, which is thus the correct, length-weighted mean tubular diameter, dL = d hS . Surface area is estimated in the ordinary way from vertical sections, and with unbiased and robust estimates of S and dL respectively, total length may be estimated L = S / πdhs Conclusion: A new stereological estimator of total length of a circular tubular structure observed in thin vertical sections is presented.

  3. Coiled sheet metal strip opens into tubular configuration

    Science.gov (United States)

    Park, J. J.

    1966-01-01

    Copper alloy is converted into a spring material that can be rolled into a compact coil which will spontaneously open to form a tube in the long direction of the strip. The copper alloy is passed through a furnace at a prescribed temperature while restraining the strip in the desired tubular configuration.

  4. Cultivation of micro-algae in closed tubular reactor

    Energy Technology Data Exchange (ETDEWEB)

    Gudin, C.; Bernard, A.; Chaumont, D.

    1983-11-01

    A description is presented of the three culture pilot utilities in activity under natural light, including glass tubular solar collector (30 mm diameter) in which the microalgae culture circulates. The utility is controled automatically (thermal regulation, gaseous transfers, continuous culture organization). The tests were conducted for the production of polysaccharides (Porphyridium cruentum, chlamydomonas mexicana) or hydrocarbons (Botriococcus braunii).

  5. An Improved Design of a Simple Tubular Reactor Experiment.

    Science.gov (United States)

    Asfour, Abdul-Fattah A.

    1985-01-01

    Background information, procedures used, and typical results obtained are provided for an experiment which: (1) examines the effect of residence time on conversion in a tubular flow reactor; and (2) compares the experimental conversions with those obtained from plug-flow and laminar-flow reactor models. (JN)

  6. Expansion of Tubular with Elastomers in Multilateral Wells

    Directory of Open Access Journals (Sweden)

    Md Velden

    2013-06-01

    Full Text Available The use of solid expandable tubular technology during the last decade has focused on solving many challenges in well drilling and delivery including zonal isolation, deep drilling, conservation of hole sizes, etc. not only as pioneered solution but also providing cost effective and long lasting solutions. Concurrently, the technology was extended for construction of multilateral in typical wells. The process of horizontal tubular expansion is similar to the vertical expansion of expandable tubular in down-hole environment with the addition of uniformly distributed force due to its weight. The expansion is targeted to increase its diameter such that post expansion characteristics remain within allowable limits. In this study a typical expandable tubular of 57.15 mm outer diameter and 6.35 mm wall thickness was used with two different elastomer seals of 5 and 7 mm thickness placed at equal spacing of 200 mm. The developed stress contours during expansion process clearly showed the high stress areas in the vicinity of expansion region which lies around the mandrel. These high stresses may result in excessive wear of the mandrel. It was also found out that the drawing force increases as the mandrel angle, expansion ratio, and friction coefficient increases. A mandrel angle of 20o  requires minimum expansion force and can be considered as an optimum geometrical parameter to lower the power required for expansion.

  7. Combined Diffusion Tensor Imaging and Transverse Relaxometry in Early-Onset Bipolar Disorder

    Science.gov (United States)

    Gonenc, Atilla; Frazier, Jean A.; Crowley, David J.; Moore, Constance M.

    2010-01-01

    Objective: Transverse relaxation time (T2) imaging provides the opportunity to examine membrane fluidity, which can affect a number of cellular functions. The objective of the present work was to examine T2 abnormalities in children with unmodified DSM-IV-TR bipolar disorder (BD) in bilateral cingulate-paracingulate (CPC) white matter. Method: A…

  8. Renal tubular function in patients treated with high-dose cisplatin

    DEFF Research Database (Denmark)

    Daugaard, G; Abildgaard, U; Holstein-Rathlou, N H

    1988-01-01

    The effect of three cycles of high-dose cisplatin (40 mg/m2 day for 5 days) on renal tubular function was evaluated in 30 patients. A significant impairment of proximal tubular salt and water reabsorption rates was observed, but also distal tubular function seemed to be affected. These changes were...... and water reabsorption during cisplatin administration....

  9. Temporal evolution of tubular initial conditions and their influence on two-particle correlations in relativistic nuclear collisions

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, R.P.G. [Instituto de Fisica, Universidade de Sao Paulo (Brazil); Grassi, F., E-mail: grassi@if.usp.br [Instituto de Fisica, Universidade de Sao Paulo (Brazil); Hama, Y. [Instituto de Fisica, Universidade de Sao Paulo (Brazil); Qian, W.-L. [Instituto de Ciencias Exatas, Universidade Federal de Ouro Preto (Brazil)

    2012-06-06

    Relativistic nuclear collisions data on two-particle correlations exhibit structures as function of relative azimuthal angle and rapidity. A unified description of these near-side and away-side structures is proposed for low to moderate transverse momentum. It is based on the combined effect of tubular initial conditions and hydrodynamical expansion. Contrary to expectations, the hydrodynamics solution shows that the high-energy density tubes (leftover from the initial particle interactions) give rise to particle emission in two directions and this is what leads to the various structures. This description is sensitive to some of the initial tube parameters and may provide a probe of the strong interaction. This explanation is compared with an alternative one where some triangularity in the initial conditions is assumed. A possible experimental test is suggested.

  10. Transverse section radionuclide scanning system

    International Nuclear Information System (INIS)

    Kuhl, D.E.; Edwards, R.Q.

    1976-01-01

    This invention provides a transverse section radionuclide scanning system for high-sensitivity quantification of brain radioactivity in cross-section picture format in order to permit accurate assessment of regional brain function localized in three dimensions. High sensitivity crucially depends on overcoming the heretofore known raster type scanning, which requires back and forth detector movement involving dead-time or partial enclosure of the scan field. Accordingly, this invention provides a detector array having no back and forth movement by interlaced detectors that enclose the scan field and rotate as an integral unit around one axis of rotation in a slip ring that continuously transmits the detector data by means of laser emitting diodes, with the advantages that increased amounts of data can be continuously collected, processed and displayed with increased sensitivity according to a suitable computer program. 5 claims, 11 figures

  11. Resolution enhancement of slam using transverse wave

    International Nuclear Information System (INIS)

    Ko, Dae Sik; Moon, Gun; Kim, Young H.

    1997-01-01

    We studied the resolution enhancement of a novel scanning laser acoustic microscope (SLAM) using transverse waves. Mode conversion of the ultrasonic wave takes place at the liquid-solid interface and some energy of the insonifying longitudinal waves in the water will convert to transverse wave energy within the solid specimen. The resolution of SLAM depends on the size of detecting laser spot and the wavelength of the insonifying ultrasonic waves. Since the wavelength of the transverse wave is shorter than that of the longitudinal wave, we are able to achieve the high resolution by using transverse waves. In order to operate SLAM in the transverse wave mode, we made wedge for changing the incident angle. Our experimental results with model 2140 SLAM and an aluminum specimen showed higher contrast of the SLAM Image In the transverse wave mode than that in the longitudinal wave mode.

  12. Serial block face SEM visualization of unusual plant nuclear tubular extensions in a carnivorous plant (Utricularia, Lentibulariaceae).

    Science.gov (United States)

    Plachno, Bartosz J; Swiatek, Piotr; Jobson, Richard W; Malota, Karol; Brutkowski, Wojciech

    2017-11-10

    In Utricularia nelumbifolia , the nuclei of placental nutritive tissue possess unusually shaped projections not known to occur in any other flowering plant. The main aim of the study was to document the morphology and ultrastructure of these unusual nuclei. In addition, the literature was searched to find examples of nuclear tubular projections in other plant groups, and the nuclei of closely related species of Utricularia (i.e. sects Iperua , Orchidioides , Foliosa and Utricularia ) were examined. To visualize the complexity of the nuclear structures, transmission electron microscopy (TEM) was used, and 3-D ultrastructural reconstructions were made using the serial block face scanning electron microscopy (SBEM) technique. The nuclei of 11 Utricularia species, i.e. U. nelumbifolia , U. reniformis , U. cornigera , U. nephrophylla (sect. Iperua ), U. asplundii , U. alpina , U. quelchii (sect. Orchidioides ), U. longifolia (sect. Foliosa ), U. intermedia , U. minor and U. gibba (sect. Utricularia ) were examined. Of the 11 Utricularia species examined, the spindle-like tubular projections (approx. 5 μm long) emanating from resident nuclei located in placental nutritive tissues were observed only in U. nelumbifolia . These tubular nuclear extensions contained chromatin distributed along hexagonally shaped tubules. The apices of the projections extended into the cell plasma membrane, and in many cases also made contact at the two opposing cellular poles, and with plasmodesmata via a short cisterna of the cortical endoplasmic reticulum. Images from the SBEM provide some evidence that the nuclear projections are making contact with those of neighbouring cells. The term chromatubules (chromatin-filled tubules) for the nuclear projections of U. nelumbifolia placental tissue was proposed here. Due to the apparent association with the plasma membrane and plasmodesmata, it was also speculated that chromatubules are involved in nucleus-cell-cell communication. However

  13. DC-SIGN reacts with TLR-4 and regulates inflammatory cytokine expression via NF-κB activation in renal tubular epithelial cells during acute renal injury.

    Science.gov (United States)

    Feng, D; Wang, Y; Liu, Y; Wu, L; Li, X; Chen, Y; Chen, Y; Chen, Y; Xu, C; Yang, K; Zhou, T

    2018-01-01

    In the pathological process of acute kidney injury (AKI), innate immune receptors are essential in inflammatory response modulation; however, the precise molecular mechanisms are still unclear. Our study sought to demonstrate the inflammatory response mechanisms in renal tubular epithelial cells via Toll-like receptor-4 (TLR-4) and dendritic cell-specific intercellular adhesion molecule 3-grabbing non-integrin 1 (DC-SIGN) signalling. We found that DC-SIGN exhibited strong expression in renal tubular epithelial cells of human acute renal injury tissues. DC-SIGN protein expression was increased significantly when renal tubular epithelial cells were exposed to lipopolysaccharide (LPS) for a short period. Furthermore, DC-SIGN was involved in the activation of p65 by TLR-4, which excluded p38 and c-Jun N-terminal kinases (JNK). Interleukin (IL)-6 and tumour necrosis factor (TNF)-α expression was decreased after DC-SIGN knock-down, and LPS induced endogenous interactions and plasma membrane co-expression between TLR-4 and DC-SIGN. These results show that DC-SIGN and TLR-4 interactions regulate inflammatory responses in renal tubular epithelial cells and participate in AKI pathogenesis. © 2017 British Society for Immunology.

  14. Longitudinal and transverse wake potentials in SLAC

    International Nuclear Information System (INIS)

    Bane, K.; Wilson, P.

    1980-01-01

    In a machine with short bunches of high peak currents, such as the SLAC collider, one needs to know the longitudinal wake potential, for the higher mode losses, and the transverse wake potential, since, for bunches passing slightly off axis, the induced transverse forces will tend to cause beam break up. The longitudinal and transverse wakes of the SLAC structure presented here, were calculated by computer using the modal method, and including an analytic extension for higher modes. (Auth.)

  15. Laparoscopic colectomy for transverse colon carcinoma.

    Science.gov (United States)

    Zmora, O; Bar-Dayan, A; Khaikin, M; Lebeydev, A; Shabtai, M; Ayalon, A; Rosin, D

    2010-03-01

    Laparoscopic resection of transverse colon carcinoma is technically demanding and was excluded from most of the large trials of laparoscopic colectomy. The aim of this study was to assess the safety, feasibility, and outcome of laparoscopic resection of carcinoma of the transverse colon. A retrospective review was performed to identify patients who underwent laparoscopic resection of transverse colon carcinoma. These patients were compared to patients who had laparoscopic resection for right and sigmoid colon carcinoma. In addition, they were compared to a historical series of patients who underwent open resection for transverse colon cancer. A total of 22 patients underwent laparoscopic resection for transverse colon carcinoma. Sixty-eight patients operated for right colon cancer and 64 operated for sigmoid colon cancer served as comparison groups. Twenty-four patients were identified for the historical open group. Intraoperative complications occurred in 4.5% of patients with transverse colon cancer compared to 5.9% (P = 1.0) and 7.8% (P = 1.0) of patients with right and sigmoid colon cancer, respectively. The early postoperative complication rate was 45, 50 (P = 1.0), and 37.5% (P = 0.22) in the three groups, respectively. Conversion was required in 1 (5%) patient in the laparoscopic transverse colon group. The conversion rate and late complications were not significantly different in the three groups. There was no significant difference in the number of lymph nodes harvested in the laparoscopic and open groups. Operative time was significantly longer in the laparoscopic transverse colectomy group when compared to all other groups (P = 0.001, 0.008, and transverse colectomy, respectively). The results of laparoscopic colon resection for transverse colon carcinoma are comparable to the results of laparoscopic resection of right or sigmoid colon cancer and open resection of transverse colon carcinoma. These results suggest that laparoscopic resection of transverse

  16. Large transverse momentum behavior of gauge theories

    International Nuclear Information System (INIS)

    Coquereaux, Robert; De Rafael, Eduardo.

    1977-05-01

    The large transverse momentum behavior of Compton scattering and Moeller scattering in Quantum Electrodynamics; and of elastic quark-quark scattering in Quantum Chromodynamics are examined in perturbation theory. The results strongly suggest that the large transverse momentum regime in gauge theories is governed by a differential equation of the Callan-Symanzik type with a suitable momentum dependent anomalous dimension term. An explicit solution for the quark-quark elastic scattering amplitude at large transverse momentum is given

  17. Deuteron transverse densities in holographic QCD

    Energy Technology Data Exchange (ETDEWEB)

    Mondal, Chandan [Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China); Indian Institute of Technology Kanpur, Department of Physics, Kanpur (India); Chakrabarti, Dipankar [Indian Institute of Technology Kanpur, Department of Physics, Kanpur (India); Zhao, Xingbo [Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China)

    2017-05-15

    We investigate the transverse charge density in the longitudinally as well as transversely polarized deuteron using the recent empirical description of the deuteron electromagnetic form factors in the framework of holographic QCD. The predictions of the holographic QCD are compared with the results of a standard phenomenological parameterization. In addition, we evaluate GPDs and the gravitational form factors for the deuteron. The longitudinal momentum densities are also investigated in the transverse plane. (orig.)

  18. Membrane fusion

    DEFF Research Database (Denmark)

    Bendix, Pól Martin

    2015-01-01

    At Stanford University, Boxer lab, I worked on membrane fusion of small unilamellar lipid vesicles to flat membranes tethered to glass surfaces. This geometry closely resembles biological systems in which liposomes fuse to plasma membranes. The fusion mechanism was studied using DNA zippering...... between complementary strands linked to the two apposing membranes closely mimicking the zippering mechanism of SNARE fusion complexes....

  19. Biobased Membrane

    NARCIS (Netherlands)

    Koenders, E.A.B.; Zlopasa, J.; Picken, S.J.

    2015-01-01

    The present invention is in the field of a composition for forming a bio-compatible membrane applicable to building material, such as concrete, cement, etc., to a meth od of applying said composition for forming a bio-compatible membrane, a biocompatible membrane, use of said membrane for various

  20. Crude biodiesel refining using membrane ultra-filtration process: An environmentally benign process

    OpenAIRE

    I.M. Atadashi; M.K. Aroua; A.R. Abdul Aziz; N.M.N. Sulaiman

    2015-01-01

    Ceramic membrane separation system was developed to simultaneously remove free glycerol and soap from crude biodiesel. Crude biodiesel produced was ultra-filtered by multi-channel tubular membrane of the pore size of 0.05 μm. The effects of process parameters: transmembrane pressure (TMP, bar), temperature (°C) and flow rate (L/min) on the membrane system were evaluated. The process parameters were then optimized using Central Composite Design (CCD) coupled with Response Surface Methodology (...

  1. Diabetes increases susceptibility of primary cultures of rat proximal tubular cells to chemically induced injury

    International Nuclear Information System (INIS)

    Zhong Qing; Terlecky, Stanley R.; Lash, Lawrence H.

    2009-01-01

    Diabetic nephropathy is characterized by increased oxidative stress and mitochondrial dysfunction. In the present study, we prepared primary cultures of proximal tubular (PT) cells from diabetic rats 30 days after an ip injection of streptozotocin and compared their susceptibility to oxidants (tert-butyl hydroperoxide, methyl vinyl ketone) and a mitochondrial toxicant (antimycin A) with that of PT cells isolated from age-matched control rats, to test the hypothesis that PT cells from diabetic rats exhibit more cellular and mitochondrial injury than those from control rats when exposed to these toxicants. PT cells from diabetic rats exhibited higher basal levels of reactive oxygen species (ROS) and higher mitochondrial membrane potential, demonstrating that the PT cells maintain the diabetic phenotype in primary culture. Incubation with either the oxidants or mitochondrial toxicant resulted in greater necrotic and apoptotic cell death, greater evidence of morphological damage, greater increases in ROS, and greater decreases in mitochondrial membrane potential in PT cells from diabetic rats than in those from control rats. Pretreatment with either the antioxidant N-acetyl-L-cysteine or a catalase mimetic provided equivalent protection of PT cells from both diabetic and control rats. Despite the greater susceptibility to oxidative and mitochondrial injury, both cytoplasmic and mitochondrial glutathione concentrations were markedly higher in PT cells from diabetic rats, suggesting an upregulation of antioxidant processes in diabetic kidney. These results support the hypothesis that primary cultures of PT cells from diabetic rats are a valid model in which to study renal cellular function in the diabetic state.

  2. Role of mitochondrial permeability transition in human renal tubular epithelial cell death induced by aristolochic acid

    International Nuclear Information System (INIS)

    Qi Xinming; Cai Yan; Gong Likun; Liu Linlin; Chen Fangping; Xiao Ying; Wu Xiongfei; Li Yan; Xue Xiang; Ren Jin

    2007-01-01

    Aristolochic acid (AA), a natural nephrotoxin and carcinogen, can induce a progressive tubulointerstitial nephropathy. However, the mechanism by which AA causes renal injury remains largely unknown. Here we reported that the mitochondrial permeability transition (MPT) plays an important role in the renal injury induced by aristolochic acid I (AAI). We found that in the presence of Ca 2+ , AAI caused mitochondrial swelling, leakage of Ca 2+ , membrane depolarization, and release of cytochrome c in isolated kidney mitochondria. These alterations were suppressed by cyclosporin A (CsA), an agent known to inhibit MPT. Culture of HK-2 cell, a human renal tubular epithelial cell line for 24 h with AAI caused a decrease in cellular ATP, mitochondrial membrane depolarization, cytochrome c release, and increase of caspase 3 activity. These toxic effects of AAI were attenuated by CsA and bongkrekic acid (BA), another specific MPT inhibitor. Furthermore, AAI greatly inhibited the activity of mitochondrial adenine nucleotide translocator (ANT) in isolated mitochondria. We suggested that ANT may mediate, at least in part, the AAI-induced MPT. Taken together, these results suggested that MPT plays a critical role in the pathogenesis of HK-2 cell injury induced by AAI and implied that MPT might contribute to human nephrotoxicity of aristolochic acid

  3. Diacylglycerol kinase α regulates tubular recycling endosome biogenesis and major histocompatibility complex class I recycling.

    Science.gov (United States)

    Xie, Shuwei; Naslavsky, Naava; Caplan, Steve

    2014-11-14

    Major histocompatibility complex class I (MHC I) presents intracellular-derived peptides to cytotoxic T lymphocytes and its subcellular itinerary is important in regulating the immune response. While a number of diacylglycerol kinase isoforms have been implicated in clathrin-dependent internalization, MHC I lacks the typical motifs known to mediate clathrin-dependent endocytosis. Here we show that depletion of diacylglycerol kinase α (DGKα), a kinase devoid of a clathrin-dependent adaptor protein complex 2 binding site, caused a delay in MHC I recycling to the plasma membrane without affecting the rate of MHC I internalization. We demonstrate that DGKα knock-down causes accumulation of intracellular and surface MHC I, resulting from decreased degradation. Furthermore, we provide evidence that DGKα is required for the generation of phosphatidic acid required for tubular recycling endosome (TRE) biogenesis. Moreover, we show that DGKα forms a complex with the TRE hub protein, MICAL-L1. Given that MICAL-L1 and the F-BAR-containing membrane-tubulating protein Syndapin2 associate selectively with phosphatidic acid, we propose a positive feedback loop in which DGKα generates phosphatidic acid to drive its own recruitment to TRE via its interaction with MICAL-L1. Our data support a novel role for the involvement of DGKα in TRE biogenesis and MHC I recycling. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  4. Evolution of the helicity and transversity Transverse-Momentum-Dependent parton distributions

    Energy Technology Data Exchange (ETDEWEB)

    Prokudin, Alexei [JLAB; Bacchetta, Alessandro [INFN-PAVIA

    2013-07-01

    We examine the QCD evolution of the helicity and transversity parton distribution functions when including also their dependence on transverse momentum. Using an appropriate definition of these polarized transverse momentum distributions (TMDs), we describe their dependence on the factorization scale and rapidity cutoff, which is essential for phenomenological applications.

  5. No generalized transverse momentum dependent factorization in the hadroproduction of high transverse momentum hadrons

    NARCIS (Netherlands)

    Rogers, T.C.; Mulders, P.J.G.

    2010-01-01

    It has by now been established that standard QCD factorization using transverse momentum dependent parton distribution functions fails in hadroproduction of nearly back-to-back hadrons with high transverse momentum. The essential problem is that gauge-invariant transverse momentum dependent parton

  6. Investigations on a new internally-heated tubular packed-bed methanol–steam reformer

    KAUST Repository

    Nehe, Prashant

    2015-05-01

    Small-scale reformers for hydrogen production through steam reforming of methanol can provide an alternative solution to the demand of continuous supply of hydrogen gas for the operation of Proton Exchange Membrane Fuel Cells (PEMFCs). A packed-bed type reformer is one of the potential designs for such purpose. An externally heated reformer has issues of adverse lower temperature in the core of the reformer and significant heat loss to the environment thus impacting its performance. Experimental and numerical studies on a new concept of internally heated tubular packed-bed methanol-steam reformer have been reported in this paper with improved performance in terms of higher methanol conversion and reduced heat losses to surroundings. CuO/ZnO/Al2O3 is used as the catalyst for the methanol-steam reforming reaction and a rod-type electric heater at the center of the reactor is used for supplying necessary heat for endothermic steam reforming reaction. The vaporizer and the reformer unit with a constant volume catalyst bed are integrated in the annular section of a tubular reformer unit. The performance of the reformer was investigated at various operating conditions like feed rate of water-methanol mixture, mass of the catalyst and reforming temperature. The experimental and numerical results show that the methanol conversion and CO concentration increase with internal heating for a wide range of operating conditions. The developed reformer unit generates 50-80W (based on lower heating value) of hydrogen gas for applications in PEMFCs. For optimized design and operating conditions, the reformer unit produced 298sccm reformed gas containing 70% H2, 27% CO2 and 3% CO at 200-240°C which can produce a power output of 25-32W assuming 60% fuel cell efficiency and 80% of hydrogen utilization in a PEMFC. © 2015 Hydrogen Energy Publications, LLC.

  7. Transverse momentum distributions of identified particles produced ...

    Indian Academy of Sciences (India)

    We assume that the transverse momentum distributions of identified particles measured in final state are contributed by a few energy sources which can be regarded as partons or quarks in the interacting system. The particle is contributed by each source with gluons which have transverse momentum distributions in an ...

  8. Transverse spin and momentum correlations in quantum ...

    Indian Academy of Sciences (India)

    These transverse momentum-dependent parton distribution functions are of significance for the analysis of azimuthal asymmetries in semi-inclusive deep inelastic scattering, as well as for the overall physical understanding of the distribution of transversely polarized quarks in unpolarized hadrons. In this context we also ...

  9. Average Transverse Momentum Quantities Approaching the Lightfront

    NARCIS (Netherlands)

    Boer, Daniel

    In this contribution to Light Cone 2014, three average transverse momentum quantities are discussed: the Sivers shift, the dijet imbalance, and the p (T) broadening. The definitions of these quantities involve integrals over all transverse momenta that are overly sensitive to the region of large

  10. Transverse spin and momentum correlations in quantum ...

    Indian Academy of Sciences (India)

    Collaboration [2] describes correlations of the intrinsic quark transverse momen- tum and the transverse nucleon ..... These results are in agreement with the large Nc predictions [41], Bag. Model results reported in [42], ..... work is supported by a grant from the US Department of Energy under contract. DE-FG02-07ER41460.

  11. Anaesthetic considerations in patients with transverse myelitis ...

    African Journals Online (AJOL)

    Transverse myelitis is an acute or subacute inflammatory disorder involving the spinal cord. Clinical signs are due to the involvement of the ascending and descending tracts in the transverse plane of the spinal cord. The most common cause is autoimmune. These patients may present with various clinical findings with ...

  12. Recovery of ammonia from swine manure using gas-permeable membranes: Effect of waste strength and pH

    Science.gov (United States)

    Nitrogen recovery of swine manure was investigated using gas-permeable membranes. The process involved a continuous recirculation of an acidic solution through a tubular gas-permeable membrane submerged in a manure filled vessel. Ammonia contained in manure was concentrated in the acidic solution ...

  13. MRI in acute transverse myelopathy

    Energy Technology Data Exchange (ETDEWEB)

    Holtaas, S. (Dept. of Diagnostic Radiology, Univ. Hospital Lund (Sweden)); Basibueyuek, N. (Dept. of Diagnostic Radiology, Univ. Hospital Lund (Sweden)); Fredriksson, K. (Dept. of Neurology, Univ. Hospital Lund (Sweden))

    1993-03-01

    The MRI examinations of seven patients with acute transverse myelopathy (ATM) were analysed. The patients were examined 2-5 times during the course of their disease with short and long TR/TE spin-echo sequences in the sagittal projection. A previous history of autoimmune disorder and/or signs of infection at the onset of ATM were present in all cases. Cerebrospinal fluid analysis showed local synthesis of immunoglobulin in the nervours system in three cases and signs of infectious myelitis in one. During the acute phase four patients had local enlargement of the cord and all had increased signal on long TR/TE sequences. The outcome was grave in the majority of patients and there seemed to be a correlation between the degree of cord enlargement, persistence of increased signal intensity and limited recovery. Atrophy and remaining high signal intensity were noted on late MRI patients with poor outcome. In one patient with probable anterior spinal artery occlusion, cavitation of the cord was seen. (orig.)

  14. Segmental tubular sodium reabsorption in type 1 diabetes

    DEFF Research Database (Denmark)

    Dieperink, H; Eshøj, O; Leyssac, P P

    1993-01-01

    Segmental tubular sodium reabsorption in Type 1 (insulin-dependent) diabetes was measured in 36 patients in a cross-sectional study including one group (n = 13) without significant albuminuria (UalbV 1), one group (n = 16) with albuminuria in the range from 30 to 300 mg 24 h-1......, and a group (n = 7) with nephropathy (UalbV > 300 mg 24 h-1). Lithium clearance was used to measure end proximal delivery. From end proximal delivery, 51Cr-EDTA clearance (GFR) and sodium clearance, segmental tubular reabsorption was calculated. For all patients, GFR was directly correlated with end proximal...... delivery (r = 0.62, p 1, the direct correlation between GFR and end proximal delivery was also significant (r = 0.77, p

  15. Luminous effectiveness of tubular light-guides in tropics

    Energy Technology Data Exchange (ETDEWEB)

    Darula, Stanislav; Kittler, Richard; Kocifaj, Miroslav [ICA, Slovak Academy of Sciences, 9, Dubravska Road, 845 03 Bratislava (Slovakia)

    2010-11-15

    Novel tubular light-guides with a transparent hemispherical cupola placed on an unobstructed flat roof collect all sunlight and skylight available at ground level year round. This advantage is heightened in the dry and sunny tropical regions where the sun rises to very high altitudes and often the hours of sunshine last throughout the whole day. Hollow light-guides with very high inner specular reflectances can transport sunbeams downward into the windowless building core very effectively. Due to the tube's diameter and length and multiple reflections, complex illuminance patterns are produced on the underside of the tube, i.e. on top of the glazed ceiling aperture that illuminates the interior space or its working plane. This paper discusses several daylight conditions in tropical interiors illuminated by tubular light-guides. The recently published HOLIGILM calculation program and the user-friendly tool HOLIGILM 4.2 have facilitated the production of this paper. (author)

  16. Tubular separate first wall for ITER-EDA

    International Nuclear Information System (INIS)

    Pizzuto, A.; Riccardi, B.; Salpietro, E.; Malavasi, G.

    1994-01-01

    The tubular solution first wall is the most suitable one to cope with the thermal stresses, the use of double wall reduces the risk of leaks inside the vacuum vessel by avoiding the growth of a crack through both walls: the soft brazing in between wall stops the growth of a crack from one tube to the other. The eddy currents induced in the tubes are low and the Halo current flowing poloidally in the tubes exert a radial pressure which is supported by the blanket box via ad hoc supporting points provided in between first wall and blanket. The tubes can be made of steel to resist a heat flux of up to 1 MW/m 2 . For higher heat loads copper or vanadium can be used. The tubular first wall can be replaced independently from the blanket. The thermo-hydraulic electro-magnetic and dynamic analysis confirm the viability of the solution proposed

  17. Acute tubular necrosis in a patient with paroxysmal nocturnal hemoglobinuria

    Directory of Open Access Journals (Sweden)

    Eranga S Wijewickrama

    2013-01-01

    Full Text Available Acute renal failure (ARF is a well-recognized complication of paroxysmal nocturnal hemoglobinuria (PNH. The predominant mechanism is intravascular hemolysis resulting in massive hemoglobinuria ARF. We report a case of acute tubular necrosis (ATN developed in the absence of overwhelming evidence of intravascular hemolysis in a 21-year-old man with anemia, who was eventually diagnosed to have PNH. The patient presented with rapidly deteriorating renal functions in the background of iron deficiency anemia, which was attributed to reflux esophagitis. There was no clinical or laboratory evidence of intravascular hemolysis. Renal biopsy revealed ATN with deposition of hemosiderin in the proximal tubular epithelial cells. Diagnosis of PNH was confirmed with a positive Ham′s test and flow cytometry. Our case emphasizes the need to consider ATN as a possible cause for ARF in patients suspected to have PNH even in the absence of overwhelming evidence of intravascular hemolysis.

  18. Kinetics of carbendazim degradation in a horizontal tubular biofilm reactor.

    Science.gov (United States)

    Alvarado-Gutiérrez, María Luisa; Ruiz-Ordaz, Nora; Galíndez-Mayer, Juvencio; Santoyo-Tepole, Fortunata; Curiel-Quesada, Everardo; García-Mena, Jaime; Ahuatzi-Chacón, Deifilia

    2017-04-01

    The fungicide carbendazim is an ecotoxic agent affecting aquatic biota. Due to its suspected hormone-disrupting effects, it is considered a "priority hazard substance" by the Water Framework Directive of the European Commission, and its degradation is of major concern. In this work, a horizontal tubular biofilm reactor (HTBR) operating in plug-flow regime was used to study the kinetics of carbendazim removal by an acclimated microbial consortium. The reactor was operated in steady state continuous culture at eight different carbendazim loading rates. The concentrations of the fungicide were determined at several distances of the HTBR. At the loading rates tested, the highest instantaneous removal rates were observed in the first section of the tubular biofilm reactor. No evidence of inhibition of the catabolic activity of the microbial community was found. Strains of the genera Flectobacillus, Klebsiella, Stenotrophomonas, and Flavobacterium were identified in the biofilm; the last three degrade carbendazim in axenic culture.

  19. Transverse spin dependent azimuthal asymmetries at COMPASS

    CERN Document Server

    Parsamyan, Bakur

    2011-01-01

    In semi-inclusive deep inelastic scattering of polarized leptons on a transversely polarized target eight target transverse spin-dependent azimuthal modulations are allowed. In the QCD parton model half of these asymmetries can be interpreted within the leading order approach and the other four are twist-three contributions. The first two leading twist asymmetries extracted by HERMES and COMPASS experiments are related: one to the transversity distribution and the Collins effect, the other to the Sivers distribution function. These results triggered a lot of interest in the past few years and allowed the first extractions of the transversity and the Sivers distribution functions of nucleon. The remaining six asymmetries were obtained by the COMPASS experiment using a 160 GeV/c longitudinally polarized muon beam and transversely polarized deuteron and proton targets. Here we review preliminary results from COMPASS proton data of 2007.

  20. [A case of carcinoma arising in a diverticulum of the transverse colon].

    Science.gov (United States)

    Nomi, Masako; Umemoto, Satoshi; Kikutake, Takashi; Hosaka, Seiji; Mase, Takahiro; Kawamoto, Shunji; Yoshida, Takahisa

    2014-11-01

    A 64 year-old woman presented with advanced, transverse colon cancer arising in the diverticulum. Tumor invasion extended beyond the serosa to the anal side of the colon. Anemia and fatigue progressed after 6 months of iron administration. The hemoglobin value was 5.3 g/dL and carcinoembryonic antigen (CEA) level was elevated to 44.2 ng/mL. A palpable and tender fist-sized mass was found in the right upper abdomen. Computed tomography (CT) revealed a low-density mass in the transverse colon invading beyond the serosa to the anal side of the colon. Right hemi-colectomy with lymph node dissection was performed. The resected specimen contained multiple diverticula including the one from which the tumor arose. Histological examination revealed a well-differentiated, tubular adenocarcinoma (UICC TNM T4bN0M0) arising in a transverse colon diverticulum. There has been no recurrence for 2 years. Colon cancer arising in a diverticulum may expand to the extra-serosa and easily invade to the adjacent organ. In such cases, malignancy should be considered.

  1. Analysis and design of offshore tubular members against ship impacts

    OpenAIRE

    Yu, Zhaolong; Amdahl, Jørgen

    2018-01-01

    Ship collisions may be critical to the operational safety of ships and offshore structures, and should be carefully designed against. This paper investigates the response of offshore tubular members subjected to vessel bow and stern impacts with the nonlinear finite element code LS-DYNA. Two 7500 tons displacement supply vessels of modern design are modeled. Force-displacement curves for bow and stern indentation by rigid tubes are compared with design curves in the DNV-GL RP C204. Next, both...

  2. Refractory rickets caused by mild distal renal tubular acidosis

    OpenAIRE

    Ji-Ho Lee; Joo Hyun Park; Tae-Sun Ha; Heon-Seok Han

    2013-01-01

    Type I (distal) renal tubular acidosis (RTA) is a disorder associated with the failure to excrete hydrogen ions from the distal renal tubule. It is characterized by hyperchloremic metabolic acidosis, an abnormal increase in urine pH, reduced urinary excretion of ammonium and bicarbonate ions, and mild deterioration in renal function. Hypercalciuria is common in distal RTA because of bone resorption, which increases as a buffer against metabolic acidosis. This can result in intractable rickets...

  3. The Temperature Response of Compact Tubular Microalgae Protobioreactors

    OpenAIRE

    Ribeiro, Robert Luis Lara; Mariano, André Bellin; Dilay, Emerson; Souza, Jeferson Avila; Ordonez, Juan Carlos; Vargas, Jose Viriato Coelho

    2009-01-01

    A mathematical and computational modeling of a photobioreactor for the determination of the transient temperature behavior in compact tubular microalgae photobioreactors is presented. The model combines theoretical concepts of thermodynamics with classical theoretical and empirical correlations of Fluid Mechanics and Heat Transfer. The physical domain is discretized with the Volume Element Model (VEM) through which the physical system (reactor pipes) is divided into lumped volumes, such...

  4. Renal tubular acidosis secondary to jejunoileal bypass for morbid obesity

    DEFF Research Database (Denmark)

    Schaffalitzky de Muckadell, O B; Ladefoged, Jens; Thorup, Jørgen Mogens

    1985-01-01

    Renal handling of acid and base was studied in patients with persistent metabolic acidosis 3-9 years after jejunoileal bypass for morbid obesity. Excretion of acid was studied before and after intravenous infusion of NH4Cl and excretion of bicarbonate after infusion of NaHCO3. Bypass patients...... groups. Fractional loss of bicarbonate in urine was higher in controls than in bypass patients. The renal impairment is classified as distal renal tubular acidosis....

  5. ELECTROLYTIC-PLASMA TREATMENT OF INNER SURFACE OF TUBULAR PRODUCTS

    Directory of Open Access Journals (Sweden)

    Yu. G. Alekseev

    2016-01-01

    Full Text Available While manufacturing a number of important tubular products stringent requirements have been imposed on quality of their inner surfaces. The well-known methods for inner surface treatment of pipes include sandblasting, chemical cleaning with acid reagents (oxalic, formic, sulfamic, orthophosphoric acids and electrochemical polishing. Disadvantages of the chemical method are cleaning-up irregularities, high metal removal, limited number of reagent application, complicated selection of reagent chemical composition and concentration, complicated and environmentally harmful recycling of waste chemicals, high cost of reagents. Low productivity at a high cost, as well as hazardous impact on personnel due to high dispersion of abrasive dust are considered as disadvantages of sandblasting. Electrochemical polishing is characterized by the following disadvantages: low processing productivity because supply of high currents is rather difficult due to electrolyte scattering capacity away from the main electrode action zone, limited length of the cavity to be treated due to heating of flexible current leads at operating current densities, application of expensive aggressive electrolytes and high costs of their recycling. A new method for polishing and cleaning of inner surfaces of tubular products based on electrolyte-plasma treatment has been developed. In comparison with the existing methods the proposed methods ensures quality processing with high intensity while applying non-toxic, environmentally friendly and cheap electrolytes. The paper presents results of investigations on technological specific features of electrolyte-plasma treatment for inner surfaces of tubular products: influence of slotted nozzle width, electrolyte flow and rate on stability of gas-vapor blanket, current density and productivity. Results of the research have made it possible to determine modes that provide stability and high productivity in the process of electrolyte

  6. Stator iron loss of tubular permanent-magnet machines \\ud

    OpenAIRE

    Amara, Y.; Wang, J.B.; Howe, D.

    2005-01-01

    While methods of determining the iron loss in rotating permanent-magnet (PM) machines have been investigated extensively, the study of iron loss in linear machines is relatively poorly documented. This paper describes a simple analytical method to predict flux density waveforms in discrete regions of the laminated stator of a tubular PM machine, and employs an established iron loss model to determine the iron loss components, on both no load and on load. Analytical predictions are compared wi...

  7. Renal tubular acidosis secondary to jejunoileal bypass for morbid obesity

    DEFF Research Database (Denmark)

    Schaffalitzky de Muckadell, O B; Ladefoged, Jens; Thorup, Jørgen Mogens

    1985-01-01

    Renal handling of acid and base was studied in patients with persistent metabolic acidosis 3-9 years after jejunoileal bypass for morbid obesity. Excretion of acid was studied before and after intravenous infusion of NH4Cl and excretion of bicarbonate after infusion of NaHCO3. Bypass patients sho...... groups. Fractional loss of bicarbonate in urine was higher in controls than in bypass patients. The renal impairment is classified as distal renal tubular acidosis....

  8. CT diagnosis of intramedulear lesions of the tubular bone

    International Nuclear Information System (INIS)

    Wagner-Manslau, C.; Feuerbach, S.; Biehl, T.

    1985-01-01

    Three cases are used to demonstrate that intramedullary masses of the tubular bones can be discovered using computered tomography even when changes in the plain film are lacking or discrete. However, it was not possible to differentiate between osteomyelitis, chondrosarcoma and enchondroma owing to the identical morphology of these three diseases. Consequently, CT does not allow any statement on type and dignity and histological clarification is indispensable. (orig./WU) [de

  9. The transverse acetabular ligament: optimizing version.

    Science.gov (United States)

    Beverland, David

    2010-09-07

    In total hip arthroplasty (THA), excessive retroversion is associated with posterior instability, anterior impingement, and resultant groin pain. Excessive anteversion can lead to anterior instability and posterior impingement. The transverse acetabular ligament straddles the inferior limit of the bony acetabulum. It is a strong load-bearing structure and, in the normal hip, in association with the labrum, provides part of the load-bearing surface for the femoral head. It is our hypothesis that the transverse acetabular ligament defines normal version for the acetabulum. In Belfast, we found that using the transverse acetabular ligament helped reduce our primary dislocation rate from 3.7% to 1%. The key is good intraoperative exposure. A grading of 1 to 4 was based on 1000 consecutive cases: (1) normal transverse acetabular ligament easily visible on exposure of the acetabulum, 49%; (2) covered by soft tissue, 35.1%--cleared by blunt dissection; (3) covered by osteophytes, 15.6%--cleared using an acetabular reamer; (4) no transverse acetabular ligament identified, 0.3%. As can be seen, the transverse acetabular ligament is only immediately visible in 49% of cases. In the other 51%, soft tissue or bone must be cleared to define the ligament. The advantages of the transverse acetabular ligament are many. It is independent of patient positioning. The cup version can be individualized by the patient. The surgeon can avoid estimating version angle of 15° to 20° intraoperatively. It is easy to teach and consistently present. It is valuable in minimally invasive surgery. Using the transverse acetabular ligament provides an acceptable dislocation rate with the posterior approach. If the cup is cradled by the transverse acetabular ligament, it helps restore acetabular joint center. However, the transverse acetabular ligament does not help with inclination. We recommend 35° of operative inclination when using the posterior approach. Copyright 2010, SLACK Incorporated.

  10. Berberine activates Nrf2 nuclear translocation and inhibits apoptosis induced by high glucose in renal tubular epithelial cells through a phosphatidylinositol 3-kinase/Akt-dependent mechanism.

    Science.gov (United States)

    Zhang, Xiuli; Liang, Dan; Lian, Xu; Jiang, Yan; He, Hui; Liang, Wei; Zhao, Yue; Chi, Zhi-Hong

    2016-06-01

    Apoptosis of tubular epithelial cells is a major feature of diabetic kidney disease, and hyperglycemia triggers the generation of free radicals and oxidant stress in tubular cells. Berberine (BBR) is identified as a potential anti-diabetic herbal medicine due to its beneficial effects on insulin sensitivity, glucose metabolism and glycolysis. In this study, the underlying mechanisms involved in the protective effects of BBR on high glucose-induced apoptosis were explored using cultured renal tubular epithelial cells (NRK-52E cells) and human kidney proximal tubular cell line (HK-2 cells). We identified the pivotal role of phosphatidylinositol 3-kinase (PI3K)/Akt in BBR cellular defense mechanisms and revealed the novel effect of BBR on nuclear factor (erythroid-derived 2)-related factor-2 (Nrf2) and heme oxygenase (HO)-1 in NRK-52E and HK-2 cells. BBR attenuated reactive oxygen species production, antioxidant defense (GSH and SOD) and oxidant-sensitive proteins (Nrf2 and HO-1), which also were blocked by LY294002 (an inhibitor of PI3K) in HG-treated NRK-52E and HK-2 cells. Furthermore, BBR improved mitochondrial function by increasing mitochondrial membrane potential. BBR-induced anti-apoptotic function was demonstrated by decreasing apoptotic proteins (cytochrome c, Bax, caspase3 and caspase9). All these findings suggest that BBR exerts the anti-apoptosis effects through activation of PI3K/Akt signal pathways and leads to activation of Nrf2 and induction of Nrf2 target genes, and consequently protecting the renal tubular epithelial cells from HG-induced apoptosis.

  11. Tubular transport and metabolism of cimetidine in chicken kidneys

    Energy Technology Data Exchange (ETDEWEB)

    Rennick, B.; Ziemniak, J.; Smith, I.; Taylor, M.; Acara, M.

    1984-02-01

    Renal tubular transport and renal metabolism of (/sup 14/C)cimetidine (CIM) were investigated by unilateral infusion into the renal portal circulation in chickens (Sperber technique). (/sup 14/C)CIM was actively transported at a rate 88% that of simultaneously infused p-aminohippuric acid, and its transport was saturable. The following organic cations competitively inhibited the tubular transport of (/sup 14/C)CIM with decreasing potency: CIM, ranitidine, thiamine, procainamide, guanidine and choline. CIM inhibited the transport of (/sup 14/C)thiamine, (/sup 14/C)amiloride and (/sup 14/C)tetraethylammonium. During CIM infusion, two renal metabolites, CIM sulfoxide and hydroxymethylcimetidine, were found in urine. When CIM sulfoxide was infused, its transport efficiency was 32% and not saturable. CIM sulfoxide did ot inhibit the simultaneous renal tubular transport of p-aminohippuric acid or tetraethylammonium. CIM is transported by the organic cation transport system and the kidney metabolizes CIM. Transport of CIM and other cationic drugs could produce a drug interaction to alter drug excretion.

  12. Plastic deformation of tubular crystals by dislocation glide.

    Science.gov (United States)

    Beller, Daniel A; Nelson, David R

    2016-09-01

    Tubular crystals, two-dimensional lattices wrapped into cylindrical topologies, arise in many contexts, including botany and biofilaments, and in physical systems such as carbon nanotubes. The geometrical principles of botanical phyllotaxis, describing the spiral packings on cylinders commonly found in nature, have found application in all these systems. Several recent studies have examined defects in tubular crystals associated with crystalline packings that must accommodate a fixed tube radius. Here we study the mechanics of tubular crystals with variable tube radius, with dislocations interposed between regions of different phyllotactic packings. Unbinding and separation of dislocation pairs with equal and opposite Burgers vectors allow the growth of one phyllotactic domain at the expense of another. In particular, glide separation of dislocations offers a low-energy mode for plastic deformations of solid tubes in response to external stresses, reconfiguring the lattice step by step. Through theory and simulation, we examine how the tube's radius and helicity affects, and is in turn altered by, the mechanics of dislocation glide. We also discuss how a sufficiently strong bending rigidity can alter or arrest the deformations of tubes with small radii.

  13. A Role for Tubular Necroptosis in Cisplatin-Induced AKI

    Science.gov (United States)

    Xu, Yanfang; Ma, Huabin; Shao, Jing; Wu, Jianfeng; Zhou, Linying; Zhang, Zhirong; Wang, Yuze; Huang, Zhe; Ren, Junming; Liu, Suhuan; Chen, Xiangmei

    2015-01-01

    Cell death and inflammation in the proximal tubules are the hallmarks of cisplatin-induced AKI, but the mechanisms underlying these effects have not been fully elucidated. Here, we investigated whether necroptosis, a type of programmed necrosis, has a role in cisplatin-induced AKI. We found that inhibition of any of the core components of the necroptotic pathway—receptor-interacting protein 1 (RIP1), RIP3, or mixed lineage kinase domain-like protein (MLKL)—by gene knockout or a chemical inhibitor diminished cisplatin-induced proximal tubule damage in mice. Similar results were obtained in cultured proximal tubular cells. Furthermore, necroptosis of cultured cells could be induced by cisplatin or by a combination of cytokines (TNF-α, TNF-related weak inducer of apoptosis, and IFN-γ) that were upregulated in proximal tubules of cisplatin-treated mice. However, cisplatin induced an increase in RIP1 and RIP3 expression in cultured tubular cells in the absence of cytokine release. Correspondingly, overexpression of RIP1 or RIP3 enhanced cisplatin-induced necroptosis in vitro. Notably, inflammatory cytokine upregulation in cisplatin-treated mice was partially diminished in RIP3- or MLKL-deficient mice, suggesting a positive feedback loop involving these genes and inflammatory cytokines that promotes necroptosis progression. Thus, our data demonstrate that necroptosis is a major mechanism of proximal tubular cell death in cisplatin-induced nephrotoxic AKI. PMID:25788533

  14. Method and apparatus for forming flues on tubular stock

    Science.gov (United States)

    Beck, D.E.; Carson, C.

    1979-12-21

    The present invention is directed to a die mechanism utilized for forming flues on long, relatively narrow tubular stock. These flues are formed by displacing a die from within the tubular stock through perforations previously drilled through the tubular stock at selected locations. The drawing of the die upsets the material to form the flue of the desired configuration. The die is provided with a lubricating system which enables the lubricant to be dispensed uniformly about the entire periphery of the die in contact with the material being upset so as to assure the formation of the flues. Further, the lubricant is dispensed from within the die onto the peripheral surface of the latter at pressures in the range of about 2000 to 10,000 psi so as to assure the adequate lubrication of the die during the drawing operation. By injecting the lubricant at such high pressures, low viscosity liquid, such as water and/or alcohol, may be efficiently used as a lubricant and also provides a mechanism by which the lubricant may be evaporated from the surface of the flues at ambient conditions so as to negate the cleansing operations previously required prior to joining the flues to other conduit mechanisms by fusion welding and the like.

  15. Thermodynamic model and parametric analysis of a tubular SOFC module

    Science.gov (United States)

    Campanari, Stefano

    Solid oxide fuel cells (SOFCs) have been considered in the last years as one of the most promising technologies for very high-efficiency electric energy generation from natural gas, both with simple fuel cell plants and with integrated gas turbine-fuel cell systems. Among the SOFC technologies, tubular SOFC stacks with internal reforming have emerged as one of the most mature technology, with a serious potential for a future commercialization. In this paper, a thermodynamic model of a tubular SOFC stack, with natural gas feeding, internal reforming of hydrocarbons and internal air preheating is proposed. In the first section of the paper, the model is discussed in detail, analyzing its calculating equations and tracing its logical steps; the model is then calibrated on the available data for a recently demonstrated tubular SOFC prototype plant. In the second section of the paper, it is carried out a detailed parametric analysis of the stack working conditions, as a function of the main operating parameters. The discussion of the results of the thermodynamic and parametric analysis yields interesting considerations about partial load SOFC operation and load regulation, and about system design and integration with gas turbine cycles.

  16. Pediatric tubular pulmonary heart valve from decellularized engineered tissue tubes.

    Science.gov (United States)

    Reimer, Jay M; Syedain, Zeeshan H; Haynie, Bee H T; Tranquillo, Robert T

    2015-09-01

    Pediatric patients account for a small portion of the heart valve replacements performed, but a pediatric pulmonary valve replacement with growth potential remains an unmet clinical need. Herein we report the first tubular heart valve made from two decellularized, engineered tissue tubes attached with absorbable sutures, which can meet this need, in principle. Engineered tissue tubes were fabricated by allowing ovine dermal fibroblasts to replace a sacrificial fibrin gel with an aligned, cell-produced collagenous matrix, which was subsequently decellularized. Previously, these engineered tubes became extensively recellularized following implantation into the sheep femoral artery. Thus, a tubular valve made from these tubes may be amenable to recellularization and, ideally, somatic growth. The suture line pattern generated three equi-spaced leaflets in the inner tube, which collapsed inward when exposed to back pressure, per tubular valve design. Valve testing was performed in a pulse duplicator system equipped with a secondary flow loop to allow for root distention. All tissue-engineered valves exhibited full leaflet opening and closing, minimal regurgitation (Valve performance was maintained under various trans-root pressure gradients and no tissue damage was evident after 2 million cycles of fatigue testing. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Intragraft Tubular Vimentin and CD44 Expression Correlate With Long-Term Renal Allograft Function and Interstitial Fibrosis and Tubular Atrophy

    NARCIS (Netherlands)

    Kers, Jesper; Xu-Dubois, Yi-Chun; Rondeau, Eric; Claessen, Nike; Idu, Mirza M.; Roelofs, Joris J. T. H.; Bemelman, Fréderike J.; ten Berge, Ineke J. M.; Florquin, Sandrine

    2010-01-01

    Background. Development of interstitial fibrosis and tubular atrophy (IF/TA) is the main histologic feature involved in renal allograft deterioration. The aim of this study was to validate whether de novo tubular expression of CD44 (transmembrane glycoprotein) and vimentin (mesenchymal cell marker),

  18. Performance Evaluations of Ion Exchanged Zeolite Membranes on Alumina Supports

    Energy Technology Data Exchange (ETDEWEB)

    Bhave, Ramesh R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jubin, Robert Thomas [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Spencer, Barry B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Nair, Sankar [Georgia Inst. of Technology, Atlanta, GA (United States)

    2017-08-27

    This report describes the synthesis and evaluation of molecular sieve zeolite membranes to separate and concentrate tritiated water (HTO) from dilute HTO-bearing aqueous streams. In the first phase of this effort, several monovalent and divalent cation-exchanged silico alumino phosphate (SAPO-34) molecular sieve zeolite membranes were synthesized on disk supports and characterized with gas and vapor permeation measurements. In the second phase, Linde Type A (LTA) zeolite membranes were synthesized in disk and tubular supports. The pervaporation process performance was evaluated for the separation and concentration of tritiated water.

  19. Membranous nephropathy

    Science.gov (United States)

    ... check for hepatitis B, hepatitis C, and syphilis Complement levels Cryoglobulin test Treatment The goal of treatment ... not as helpful for people with membranous nephropathy. Medicines used treat membranous nephropathy include: Angiotensin-converting enzyme ( ...

  20. Directional Transverse Oscillation Vector Flow Estimation

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt

    2017-01-01

    A method for estimating vector velocities using transverse oscillation (TO) combined with directional beamforming is presented. In Directional Transverse Oscillation (DTO) a normal focused field is emitted and the received signals are beamformed in the lateral direction transverse to the ultrasound...... beam to increase the amount of data for vector velocity estimation. The approach is self-calibrating as the lateral oscillation period is estimated from the directional signal through a Fourier transform to yield quantitative velocity results over a large range of depths. The approach was extensively...

  1. Ferroelectric Cathodes in Transverse Magnetic Fields

    International Nuclear Information System (INIS)

    Alexander Dunaevsky; Yevgeny Raitses; Nathaniel J. Fisch

    2002-01-01

    Experimental investigations of a planar ferroelectric cathode in a transverse magnetic field up to 3 kGs are presented. It is shown that the transverse magnetic field affects differently the operation of ferroelectric plasma cathodes in ''bright'' and ''dark'' modes in vacuum. In the ''bright'' mode, when the surface plasma is formed, the application of the transverse magnetic field leads to an increase of the surface plasma density. In the ''dark'' mode, the magnetic field inhibits the development of electron avalanches along the surface, as it does similarly in other kinds of surface discharges in the pre-breakdown mode

  2. Scaling properties of the transverse mass spectra

    International Nuclear Information System (INIS)

    Schaffner-Bielich, J.

    2002-01-01

    Motivated from the formation of an initial state of gluon-saturated matter, we discuss scaling relations for the transverse mass spectra at BNL's relativistic heavy-ion collider (RHIC). We show on linear plots, that the transverse mass spectra for various hadrons can be described by an universal function in m t . The transverse mass spectra for different centralities can be rescaled into each other. Finally, we demonstrate that m t -scaling is also present in proton-antiproton collider data and compare it to m t -scaling at RHIC. (orig.)

  3. Bioinspired coupled helical coils for soft tissue engineering of tubular structures - Improved mechanical behavior of tubular collagen type I templates.

    Science.gov (United States)

    Janke, H P; Bohlin, J; Lomme, R M L M; Mihaila, S M; Hilborn, J; Feitz, W F J; Oosterwijk, E

    2017-09-01

    The design of constructs for tubular tissue engineering is challenging. Most biomaterials need to be reinforced with supporting structures such as knittings, meshes or electrospun material to comply with the mechanical demands of native tissues. In this study, coupled helical coils (CHCs) were manufactured to mimic collagen fiber orientation as found in nature. Monofilaments of different commercially available biodegradable polymers were wound and subsequently fused, resulting in right-handed and left-handed polymer helices fused together in joints where the filaments cross. CHCs of different polymer composition were tested to determine the tensile strength, strain recovery, hysteresis, compressive strength and degradation of CHCs of different composition. Subsequently, seamless and stable hybrid constructs consisting of PDSII® USP 2-0 CHCs embedded in porous collagen type I were produced. Compared to collagen alone, this hybrid showed superior strain recovery (93.5±0.9% vs 71.1±12.6% in longitudinal direction; 87.1±6.6% vs 57.2±4.6% in circumferential direction) and hysteresis (18.9±2.7% vs 51.1±12.0% in longitudinal direction; 11.5±4.6% vs 46.3±6.3% in circumferential direction). Furthermore, this hybrid construct showed an improved Young's modulus in both longitudinal (0.5±0.1MPavs 0.2±0.1MPa; 2.5-fold) and circumferential (1.65±0.07MPavs (2.9±0.3)×10 -2 MPa; 57-fold) direction, respectively, compared to templates created from collagen alone. Moreover, hybrid template characteristics could be modified by changing the CHC composition and CHCs were produced showing a mechanical behavior similar to the native ureter. CHC-enforced templates, which are easily tunable to meet different demands may be promising for tubular tissue engineering. Most tubular constructs lack sufficient strength and tunability to comply with the mechanical demands of native tissues. Therefore, we embedded coupled helical coils (CHCs) produced from biodegradable polymers - to

  4. Membrane Biophysics

    CERN Document Server

    Ashrafuzzaman, Mohammad

    2013-01-01

    Physics, mathematics and chemistry all play a vital role in understanding the true nature and functioning of biological membranes, key elements of living processes. Besides simple spectroscopic observations and electrical measurements of membranes we address in this book the phenomena of coexistence and independent existence of different membrane components using various theoretical approaches. This treatment will be helpful for readers who want to understand biological processes by applying both simple observations and fundamental scientific analysis. It provides a deep understanding of the causes and effects of processes inside membranes, and will thus eventually open new doors for high-level pharmaceutical approaches towards fighting membrane- and cell-related diseases.

  5. Compressive membrane action in concrete decks

    NARCIS (Netherlands)

    Amir, S.

    2012-01-01

    One of the major challenges facing the designers today is to investigate if the old bridges are still safe for modern traffic. The current research deals with this question by taking into account compressive membrane action (CMA) in determining the capacity of reinforced and transversely prestressed

  6. Constituent models and large transverse momentum reactions

    International Nuclear Information System (INIS)

    Brodsky, S.J.

    1975-01-01

    The discussion of constituent models and large transverse momentum reactions includes the structure of hard scattering models, dimensional counting rules for large transverse momentum reactions, dimensional counting and exclusive processes, the deuteron form factor, applications to inclusive reactions, predictions for meson and photon beams, the charge-cubed test for the e/sup +-/p → e/sup +-/γX asymmetry, the quasi-elastic peak in inclusive hadronic reactions, correlations, and the multiplicity bump at large transverse momentum. Also covered are the partition method for bound state calculations, proofs of dimensional counting, minimal neutralization and quark--quark scattering, the development of the constituent interchange model, and the A dependence of high transverse momentum reactions

  7. Transverse steering of two-component beams

    International Nuclear Information System (INIS)

    Murin, B.P.; Bondarev, B.U.; Durkin, A.P.; Lomize, L.G.; Soloviev, L.Yu.; Fedotov, A.P.

    Coherent transverse oscillations are considered which occur during simultaneous acceleration of proton and H - beams due to arbitrary displacements in elements of the focusing channel. To suppress these oscillations, a beam adjustment station is proposed, in which each quadrupole lens of two doublets is provided with a special dipole component of the magnetic field. These steering elements, together with the beam transverse position monitors, permit steering the transverse position of beams of opposite signs in both transverse planes. The number of steering stations needed is chosen, and some algorithms for control are discussed. It is shown that some of the control algorithms will permit not only the suppression of coherent oscillations, but a decrease in the radius and emittance of the beam

  8. A young woman with recurrent kidney stones: questions on hypokalaemic tubular acidosis

    Directory of Open Access Journals (Sweden)

    Jill Vanmassenhove

    2017-04-01

    Full Text Available This paper discusses the diagnostic and therapeutic approach to the problem of a young woman presenting with recurrent kidney stones. In the clinical work-up, a hypokalaemic normal anion gap metabolic acidosis was found. The diagnostic tests to solve this common clinical problem and some therapeutic recommendations are discussed. Question on hypokalaemic tubular acidosis: 1. What is the significance of the plasma anion gap (PAG? 2. How does one appreciate the respiratory component of the acid base status? 3. How does one perform tests for tubular acidification disturbances? 4. What is the pathogenesis of distal tubular acidification ­disturbances? 5. What is the explanation of the hypokalaemia in distal ­tubular acidosis? 6. What is the pathogenesis of nephrolithiasis in distal tubular acidosis? 7. How does one treat a patient with distal tubular acidosis and recurrent nephrolithiasis?

  9. ZnO Nanorod-Induced Heteroepitaxial Growth of SOD Type Co-Based Zeolitic Imidazolate Framework Membranes for H2 Separation.

    Science.gov (United States)

    Nian, Pei; Li, Yujia; Zhang, Xiang; Cao, Yi; Liu, Haiou; Zhang, Xiongfu

    2018-01-31

    Up to now, the fabrication of well-intergrown Co-based zeolitic imidazolate framework (ZIF) membranes on porous tubular supports is still a major challenge. We report here a heteroepitaxial growth for preparing well-intergrown Co-based ZIFs (ZIF-67 and ZIF-9) tubular membranes with high performance and excellent thermal stability by employing a thin layer of ZnO nanorods acting as both nucleation centers and anchor sites for the growth of metal-organic framework membranes. The results show that well-intergrown Co-ZIF-67 and Co-ZIF-9 membranes are successfully achieved on the ZnO nanorod-modified porous ceramic tubes. This highly active heteroepitaxial growth may be attributed to the fact that the (Zn,Co) hydroxy double salt intermediate produced in situ from ZnO nanorods acts as heteroseeds and enables the uniform growth of Co-based membranes. The H 2 /CO 2 selectivity of the as-prepared Co-ZIF-9 tubular membrane could reach about 23.8 and the H 2 /CH 4 selectivity of Co-ZIF-67 tubular membrane is as high as 45.4. Moreover, the membranes demonstrate excellent stability because of the ZnO nanorods as linkers between the membrane and substrate.

  10. Elliptic flow coefficients from transverse momentum conservation

    Science.gov (United States)

    Bzdak, Adam; Ma, Guo-Liang

    2018-01-01

    We calculate the k -particle (k =2 ,4 ,6 ,8 ) azimuthal cumulants resulting from the conservation of transverse momentum. We find that c2{k } >0 and, depending on the transverse momenta, c2{k } can reach substantial values even for a relatively large number of particles. The impact of our results on the understanding of the onset of collectivity in small systems is emphasized.

  11. Parametric Transverse Patterns in Broad Aperture Lasers

    DEFF Research Database (Denmark)

    Grigorieva, E.V.; Kashchenko, S.A.; Mosekilde, Erik

    1998-01-01

    Parametrically generated optical patterns are investigated for finite and large-scale transverse aperture lasers. Standing and rotating patterns as well as periodic and chaotic pattern alternations are described in the framework of the amplitude equation formalism. Sensitive dependence on the geo......Parametrically generated optical patterns are investigated for finite and large-scale transverse aperture lasers. Standing and rotating patterns as well as periodic and chaotic pattern alternations are described in the framework of the amplitude equation formalism. Sensitive dependence...

  12. Chiral dynamics and peripheral transverse densities

    Energy Technology Data Exchange (ETDEWEB)

    Granados, Carlos G. [Uppsala University (Sweden); Weiss, Christian [JLAB, Newport News, VA (United States)

    2014-01-01

    In the partonic (or light-front) description of relativistic systems the electromagnetic form factors are expressed in terms of frame-independent charge and magnetization densities in transverse space. This formulation allows one to identify the chiral components of nucleon structure as the peripheral densities at transverse distances b = O(M{sub {pi}}{sup -1}) and compute them in a parametrically controlled manner. A dispersion relation connects the large-distance behavior of the transverse charge and magnetization densities to the spectral functions of the Dirac and Pauli form factors near the two--pion threshold at timelike t = 4 M{ sub {pi}}{sup 2}, which can be computed in relativistic chiral effective field theory. Using the leading-order approximation we (a) derive the asymptotic behavior (Yukawa tail) of the isovector transverse densities in the "chiral" region b = O(M{sub {pi}}{sup -1}) and the "molecular" region b = O(M{sub N}{sup 2}/M{sub {pi}}{sup 3}); (b) perform the heavy-baryon expansion of the transverse densities; (c) explain the relative magnitude of the peripheral charge and magnetization densities in a simple mechanical picture; (d) include Delta isobar intermediate states and study the peripheral transverse densities in the large-N{ sub c} limit of QCD; (e) quantify the region of transverse distances where the chiral components of the densities are numerically dominant; (f) calculate the chiral divergences of the b{sup 2}-weighted moments of the isovector transverse densities (charge and anomalous magnetic radii) in the limit M{sub {pi}} -> 0 and determine their spatial support. Our approach provides a concise formulation of the spatial structure of the nucleon's chiral component and offers new insights into basic properties of the chiral expansion. It relates the information extracted from low-t elastic form factors to the generalized parton distributions probed in peripheral high-energy scattering processes.

  13. Method and tool for contracting tubular members by electro-hydraulic forming before hydroforming

    Science.gov (United States)

    Golovashchenko, Sergey Fedorovich [Beverly Hills, MI

    2011-03-15

    A tubular preform is contracted in an electro-hydraulic forming operation. The tubular preform is wrapped with one or more coils of wire and placed in a chamber of an electro-hydraulic forming tool. The electro-hydraulic forming tool is discharged to form a compressed area on a portion of the tube. The tube is then placed in a hydroforming tool that expands the tubular preform to form a part.

  14. Transverse angular momentum in topological photonic crystals

    Science.gov (United States)

    Deng, Wei-Min; Chen, Xiao-Dong; Zhao, Fu-Li; Dong, Jian-Wen

    2018-01-01

    Engineering local angular momentum of structured light fields in real space enables applications in many fields, in particular, the realization of unidirectional robust transport in topological photonic crystals with a non-trivial Berry vortex in momentum space. Here, we show transverse angular momentum modes in silicon topological photonic crystals when considering transverse electric polarization. Excited by a chiral external source with either transverse spin angular momentum or transverse phase vortex, robust light flow propagating along opposite directions is observed in several kinds of sharp-turn interfaces between two topologically-distinct silicon photonic crystals. A transverse orbital angular momentum mode with alternating phase vortex exists at the boundary of two such photonic crystals. In addition, unidirectional transport is robust to the working frequency even when the ring size or location of the pseudo-spin source varies in a certain range, leading to the superiority of the broadband photonic device. These findings enable one to make use of transverse angular momentum, a kind of degree of freedom, to achieve unidirectional robust transport in the telecom region and other potential applications in integrated photonic circuits, such as on-chip robust delay lines.

  15. Transverse structure of the QCD string

    International Nuclear Information System (INIS)

    Meyer, Harvey B.

    2010-01-01

    The characterization of the transverse structure of the QCD string is discussed. We formulate a conjecture as to how the stress-energy tensor of the underlying gauge theory couples to the string degrees of freedom. A consequence of the conjecture is that the energy density and the longitudinal-stress operators measure the distribution of the transverse position of the string, to leading order in the string fluctuations, whereas the transverse-stress operator does not. We interpret recent numerical measurements of the transverse size of the confining string and show that the difference of the energy and longitudinal-stress operators is a particularly natural probe at next-to-leading order. Second, we derive the constraints imposed by open-closed string duality on the transverse structure of the string. We show that a total of three independent ''gravitational'' form factors characterize the transverse profile of the closed string, and obtain the interpretation of recent effective string theory calculations: the square radius of a closed string of length β defined from the slope of its gravitational form factor, is given by (d-1/2πσ)log(β/4r 0 ) in d space dimensions. This is to be compared with the well-known result that the width of the open string at midpoint grows as (d-1/2πσ)log(r/r 0 ). We also obtain predictions for transition form factors among closed-string states.

  16. A Study of Large Transverse Momentum Phenomena

    CERN Multimedia

    2002-01-01

    This experiment studies the structure of those p-p and @*-p collisions which are characterized by a very high transverse momentum flow in the central region. Some specific items studied are:\\\\ \\\\ \\item -~~Structure of events, where the high transverse momentum is shared by charged and neutral hadron (``jets''). Transverse momentum distribution, correlations and momentum balance for such events. \\item -~~Structure of events, where the high transverse momentum is mostly carried by one identified particle. Quantum number dependence and quantum number correlations of the high transverse momentum events. \\item -~~Structure of events containing large transverse momentum leptons or lepton pairs or direct photons. \\end{enumerate}.sk -~~Study of low momentum electrons and photons. -~~Search for gluonium states. -~~Search for new and rare particles. \\\\ \\\\ A conventional C-type magnet with a 0.5 T field in the direction of the beams together with a 42-layer cylindrical drift chamber detector is used for momentum analysi...

  17. Evaluation of the photocathode laser transverse distribution

    Energy Technology Data Exchange (ETDEWEB)

    Saisa-ard, Chaipattana [DESY, Zeuthen (Germany); Chiang Mai Univ., Chiang Mai (Thailand); Krasilnikov, Mikhail; Vashchenko, Grygorii [DESY, Zeuthen (Germany)

    2016-07-01

    Many years experience of electron source developments at the photo injector test facility at DESY in Zeuthen (PITZ) show that the photocathode laser is the one of major tools to produce high brightness electron beams. The transverse distribution of the laser on the photocathode plays a significant role in the high brightness photo injector optimization. However, the imperfections in the laser beam profile according to the deviation from a radially homogeneous profile directly result in transversely distorted charged particle distributions. This includes inhomogeneous core as well as transverse halo which is due to not sharp edges around the core. The laser transverse distribution is measured at PITZ using a virtual cathode:this is a CCD camera located at the position which is optically equivalent to the photocathode position (so called virtual cathode). An algorithm is developed for the evaluation of the experimentally obtained transverse profiles. It fits a flat-top or an inhomogeneous rotational symmetric core with exponentially decaying tails to an experimental distribution. The MATLAB script with implemented algorithm is applied to a set of measured transverse laser distributions. Results of the analysis will be presented.

  18. Competitive Inhibition of Renal Tubular Secretion of Gemifloxacin by Probenecid▿

    Science.gov (United States)

    Landersdorfer, Cornelia B.; Kirkpatrick, Carl M. J.; Kinzig, Martina; Bulitta, Jürgen B.; Holzgrabe, Ulrike; Drusano, George L.; Sörgel, Fritz

    2009-01-01

    Probenecid interacts with transport processes of drugs at several sites in the body. For most quinolones, renal clearance is reduced by concomitant administration of probenecid. The interaction between gemifloxacin and probenecid has not yet been studied. We studied the extent, time course, site(s), and mechanism of this interaction. Seventeen healthy volunteers participated in a randomized, two-way crossover study. Subjects received 320 mg gemifloxacin as an oral tablet without and with 4.5 g probenecid divided in eight oral doses. Drug concentrations in plasma and urine were analyzed by liquid chromatography-tandem mass spectrometry. WinNonlin was used for noncompartmental analysis, compartmental modeling, and statistics, and NONMEM was used for visual predictive checks. Concomitant administration of probenecid increased plasma gemifloxacin concentrations and amounts excreted in urine compared to baseline amounts. Data are average estimates (percent coefficients of variation). Modeling showed a competitive inhibition of the renal tubular secretion of gemifloxacin by probenecid as the most likely mechanism of the interaction. The estimated Km and Vmax for the saturable part of renal elimination were 9.16 mg/liter (20%) and 113 mg/h (21%), respectively. Based on the molar ratio, the affinity for the renal transporter was 10-fold higher for gemifloxacin than for probenecid. Since probenecid reached an ∼200-times-higher area under the molar concentration-time curve from 0 to 24 h than gemifloxacin, probenecid inhibited the active tubular secretion of gemifloxacin. Probenecid also reduced the nonrenal clearance of gemifloxacin from 25.2 (26%) to 21.0 (23%) liters/h. Probenecid inhibited the renal tubular secretion of gemifloxacin, most likely by a competitive mechanism, and slightly decreased nonrenal clearance of gemifloxacin. PMID:19564368

  19. Competitive inhibition of renal tubular secretion of gemifloxacin by probenecid.

    Science.gov (United States)

    Landersdorfer, Cornelia B; Kirkpatrick, Carl M J; Kinzig, Martina; Bulitta, Jürgen B; Holzgrabe, Ulrike; Drusano, George L; Sörgel, Fritz

    2009-09-01

    Probenecid interacts with transport processes of drugs at several sites in the body. For most quinolones, renal clearance is reduced by concomitant administration of probenecid. The interaction between gemifloxacin and probenecid has not yet been studied. We studied the extent, time course, site(s), and mechanism of this interaction. Seventeen healthy volunteers participated in a randomized, two-way crossover study. Subjects received 320 mg gemifloxacin as an oral tablet without and with 4.5 g probenecid divided in eight oral doses. Drug concentrations in plasma and urine were analyzed by liquid chromatography-tandem mass spectrometry. WinNonlin was used for noncompartmental analysis, compartmental modeling, and statistics, and NONMEM was used for visual predictive checks. Concomitant administration of probenecid increased plasma gemifloxacin concentrations and amounts excreted in urine compared to baseline amounts. Data are average estimates (percent coefficients of variation). Modeling showed a competitive inhibition of the renal tubular secretion of gemifloxacin by probenecid as the most likely mechanism of the interaction. The estimated K(m) and Vmax for the saturable part of renal elimination were 9.16 mg/liter (20%) and 113 mg/h (21%), respectively. Based on the molar ratio, the affinity for the renal transporter was 10-fold higher for gemifloxacin than for probenecid. Since probenecid reached an approximately 200-times-higher area under the molar concentration-time curve from 0 to 24 h than gemifloxacin, probenecid inhibited the active tubular secretion of gemifloxacin. Probenecid also reduced the nonrenal clearance of gemifloxacin from 25.2 (26%) to 21.0 (23%) liters/h. Probenecid inhibited the renal tubular secretion of gemifloxacin, most likely by a competitive mechanism, and slightly decreased nonrenal clearance of gemifloxacin.

  20. The role of duplex stainless steels for downhole tubulars

    International Nuclear Information System (INIS)

    Francis, R.

    1993-01-01

    In sour conditions there is an increasing trend to turn to corrosion resistant alloys for downhole tubulars. The most commonly used CRA tubular is 13Cr, and there are thousands of feet in service. However, there are limits to the use of 13Cr, ie., the risk of sulphide stress corrosion cracking at high H 2 S levels, and the possibility of pitting or high corrosion rates in waters with high chloride contents. Where the service conditions are felt to be too severe for 13Cr alloys it has been traditional to switch to nickel base alloys such as alloys 825 and C-276 (UNS N08825 and N10276). The alloys are much more expensive than 13Cr, and in recent years the duplex stainless steels have been selected as alloys with superior corrosion and SSCC resistance compared with 13Cr, and having lower cost than nickel alloys. Originally the 22Cr duplex alloy (UNS 31803) was used, but more recently the 25Cr super duplex alloys (UNS S32760 and S32750) have become more available. The present paper reviews the data available for 13Cr and the limits of applicability. Data is also presented for laboratory tests for both the 22Cr and 25Cr super duplex alloys. There is extensive service experience with both 22Cr and 25Cr super duplex in the North Sea, covering both downhole tubulars, manifold and post wellhead equipment. Data is presented showing some of the sour condition being experienced in the North Sea by super duplex alloys. These results show that there is a substantial gap between the limits of use for 13Cr and the 25Cr super duplex stainless steel alloys. This means that in many sour environments super duplex stainless steel provides a cost effective alternative to nickel-base alloys

  1. Tubular overexpression of gremlin induces renal damage susceptibility in mice.

    Directory of Open Access Journals (Sweden)

    Alejandra Droguett

    Full Text Available A growing number of patients are recognized worldwide to have chronic kidney disease. Glomerular and interstitial fibrosis are hallmarks of renal progression. However, fibrosis of the kidney remains an unresolved challenge, and its molecular mechanisms are still not fully understood. Gremlin is an embryogenic gene that has been shown to play a key role in nephrogenesis, and its expression is generally low in the normal adult kidney. However, gremlin expression is elevated in many human renal diseases, including diabetic nephropathy, pauci-immune glomerulonephritis and chronic allograft nephropathy. Several studies have proposed that gremlin may be involved in renal damage by acting as a downstream mediator of TGF-β. To examine the in vivo role of gremlin in kidney pathophysiology, we generated seven viable transgenic mouse lines expressing human gremlin (GREM1 specifically in renal proximal tubular epithelial cells under the control of an androgen-regulated promoter. These lines demonstrated 1.2- to 200-fold increased GREM1 expression. GREM1 transgenic mice presented a normal phenotype and were without proteinuria and renal function involvement. In response to the acute renal damage cause by folic acid nephrotoxicity, tubule-specific GREM1 transgenic mice developed increased proteinuria after 7 and 14 days compared with wild-type treated mice. At 14 days tubular lesions, such as dilatation, epithelium flattening and hyaline casts, with interstitial cell infiltration and mild fibrosis were significantly more prominent in transgenic mice than wild-type mice. Tubular GREM1 overexpression was correlated with the renal upregulation of profibrotic factors, such as TGF-β and αSMA, and with increased numbers of monocytes/macrophages and lymphocytes compared to wild-type mice. Taken together, our results suggest that GREM1-overexpressing mice have an increased susceptibility to renal damage, supporting the involvement of gremlin in renal damage

  2. High temperature helical tubular receiver for concentrating solar power system

    Science.gov (United States)

    Hossain, Nazmul

    In the field of conventional cleaner power generation technology, concentrating solar power systems have introduced remarkable opportunity. In a solar power tower, solar energy concentrated by the heliostats at a single point produces very high temperature. Falling solid particles or heat transfer fluid passing through that high temperature region absorbs heat to generate electricity. Increasing the residence time will result in more heat gain and increase efficiency. A novel design of solar receiver for both fluid and solid particle is approached in this paper which can increase residence time resulting in higher temperature gain in one cycle compared to conventional receivers. The helical tubular solar receiver placed at the focused sunlight region meets the higher outlet temperature and efficiency. A vertical tubular receiver is modeled and analyzed for single phase flow with molten salt as heat transfer fluid and alloy625 as heat transfer material. The result is compared to a journal paper of similar numerical and experimental setup for validating our modeling. New types of helical tubular solar receivers are modeled and analyzed with heat transfer fluid turbulent flow in single phase, and granular particle and air plug flow in multiphase to observe the temperature rise in one cyclic operation. The Discrete Ordinate radiation model is used for numerical analysis with simulation software Ansys Fluent 15.0. The Eulerian granular multiphase model is used for multiphase flow. Applying the same modeling parameters and boundary conditions, the results of vertical and helical receivers are compared. With a helical receiver, higher temperature gain of heat transfer fluid is achieved in one cycle for both single phase and multiphase flow compared to the vertical receiver. Performance is also observed by varying dimension of helical receiver.

  3. A CFD analysis of transport phenomena and electrochemical reactions in a tubular-shaped PEM fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Sadiq Al-Baghdadi, Maher A.R. [Fuel Cell Research Center, International Energy and Environment Foundation, Al-Najaf, P.O.Box 39 (Iraq)

    2013-07-01

    A fuel cell is most interesting new power source because it solves not only the environment problem but also natural resource exhaustion problem. CFD modeling and simulation for heat and mass transport in PEM fuel cells are being used extensively in researches and industrial applications to gain better understanding of the fundamental processes and to optimize fuel cell designs before building a prototype for engineering application. In this research, full three-dimensional, non-isothermal computational fluid dynamics model of a tubular-shaped proton exchange membrane (PEM) fuel cell has been developed. This comprehensive model accounts for the major transport phenomena such as convective and diffusive heat and mass transfer, electrode kinetics, transport and phase-change mechanism of water, and potential fields in a tubular-shaped PEM fuel cell. The model explains many interacting, complex electrochemical, and transport phenomena that cannot be studied experimentally. Three-dimensional results of the species profiles, temperature distribution, potential distribution, and local current density distribution are presented and analysed, with the focus on the physical insight and fundamental understanding.

  4. Synergy between type 1 fimbriae expression and C3 opsonisation increases internalisation of E. coli by human tubular epithelial cells.

    Science.gov (United States)

    Li, Ke; Zhou, Wuding; Hong, Yuzhi; Sacks, Steven H; Sheerin, Neil S

    2009-03-31

    Bacterial infection of the urinary tract is a common clinical problem with E. coli being the most common urinary pathogen. Bacterial uptake into epithelial cells is increasingly recognised as an important feature of infection. Bacterial virulence factors, especially fimbrial adhesins, have been conclusively shown to promote host cell invasion. Our recent study reported that C3 opsonisation markedly increases the ability of E. coli strain J96 to internalise into human proximal tubular epithelial cells via CD46, a complement regulatory protein expressed on host cell membrane. In this study, we further assessed whether C3-dependent internalisation by human tubular epithelial cells is a general feature of uropathogenic E. coli and investigated features of the bacterial phenotype that may account for any heterogeneity. In 31 clinical isolates of E. coli tested, C3-dependent internalisation was evident in 10 isolates. Type 1 fimbriae mediated-binding is essential for C3-dependent internalisation as shown by phenotypic association, type 1 fimbrial blockade with soluble ligand (mannose) and by assessment of a type 1 fimbrial mutant. we propose that efficient internalisation of uropathogenic E. coli by the human urinary tract depends on co-operation between type 1 fimbriae-mediated adhesion and C3 receptor -ligand interaction.

  5. Distal renal tubular acidosis in a child with HIV infection

    Directory of Open Access Journals (Sweden)

    Preeti Shanbag

    2012-01-01

    Full Text Available Renal tubular acidosis (RTA is not uncommon in HIV-infected children with ad-vanced disease, and has been described mainly due to nephrotoxic anti-retroviral therapy and in association with prophylaxis or treatment of Pneumocystis carinii pneumonia with co-trimoxazole. We describe an 8-year-old boy, newly diagnosed to have HIV infection, who presented with distal RTA. There were no features of chronic RTA in the form of rickets or nephrocalcinosis, making an inherited form unlikely.

  6. Refractory rickets caused by mild distal renal tubular acidosis

    Directory of Open Access Journals (Sweden)

    Ji-Ho Lee

    2013-09-01

    Full Text Available Type I (distal renal tubular acidosis (RTA is a disorder associated with the failure to excrete hydrogen ions from the distal renal tubule. It is characterized by hyperchloremic metabolic acidosis, an abnormal increase in urine pH, reduced urinary excretion of ammonium and bicarbonate ions, and mild deterioration in renal function. Hypercalciuria is common in distal RTA because of bone resorption, which increases as a buffer against metabolic acidosis. This can result in intractable rickets. We describe a case of distal RTA with nephrocalcinosis during follow-up of rickets in a patient who presented with clinical manifestations of short stature, failure to thrive, recurrent vomiting, dehydration, and irritability.

  7. Concomitant hypercalcemia and hyperammonemia associated with distal renal tubular acidosis.

    Science.gov (United States)

    Saini, Arun; Karmakar, Swati A; Kannikeswaran, Nirupama

    2012-03-01

    We describe an infant with concomitant hypercalcemia and hyperammonemia associated with nonanion gap metabolic acidosis secondary to distal renal tubular acidosis (dRTA). The levels of both serum calcium and ammonia rapidly normalized with the correction of dehydration and metabolic acidosis. To the best of our knowledge, there has been only one previous case report of concomitant hypercalcemia and hyperammonemia associated with dRTA that has been reported in the literature. We describe the causes and emergent management of hypercalcemia and review the possible mechanisms of this rare association with dRTA.

  8. Theoretical flow investigations of an all glass evacuated tubular collector

    DEFF Research Database (Denmark)

    Shah, Louise Jivan; Furbo, Simon

    2007-01-01

    Heat transfer and flow structures inside all glass evacuated tubular collectors for different operating conditions are investigated by means of computational fluid dynamics. The investigations are based on a collector design with horizontal tubes connected to a vertical 14 manifold channel. Three...... the highest efficiency, the optimal inlet flow rate was around 0.4-1 kg/min, the flow structures in the glass tubes were relatively uninfluenced by the inlet flow rate, Generally, the results showed only small variations in the efficiencies. This indicates that the collector design is well working for most...

  9. Distal renal tubular acidosis and amelogenesis imperfecta: A rare association

    Directory of Open Access Journals (Sweden)

    P Ravi

    2013-01-01

    Full Text Available Renal tubular acidosis (RTA is characterized by a normal anion gap with hyperchloremic metabolic acidosis. Primary distal RTA (type I is the most common RTA in children. Childhood presentation of distal RTA includes vomiting, failure to thrive, metabolic acidosis, and hypokalemia. Amelogenesis imperfecta (AI represents a condition where the dental enamel and oral tissues are affected in an equal manner resulting in the hypoplastic or hypopigmented teeth. We report a 10-year-old girl, previously asymptomatic presented with the hypokalemic paralysis and on work-up found out to have type I RTA. The discoloration of teeth and enamel was diagnosed as AI.

  10. Type 4 renal tubular acidosis in a kidney transplant recipient

    Directory of Open Access Journals (Sweden)

    Manjunath Kulkarni

    2016-02-01

    Full Text Available We report a case of a 66-year-old diabetic patient who presented with muscle weakness 2 weeks after kidney transplantation. Her immunosuppressive regimen included tacrolimus, mycophenolate mofetil, and steroids. She was found to have hyperkalemia and normal anion gap metabolic acidosis. Tacrolimus levels were in therapeutic range. All other drugs such as beta blockers and trimethoprim – sulfamethoxazole were stopped. She did not respond to routine antikalemic measures. Further evaluation revealed type 4 renal tubular acidosis. Serum potassium levels returned to normal after starting sodium bicarbonate and fludrocortisone therapy. Though hyperkalemia is common in kidney transplant recipients, determining exact cause can guide specific treatment.

  11. Screening renal stone formers for distal renal tubular acidosis

    DEFF Research Database (Denmark)

    Osther, P J; Hansen, A B; Røhl, H F

    1989-01-01

    A group of 110 consecutive renal stone formers were screened for distal renal tubular acidosis (RTA) using morning fasting urinary pH (mfUpH) levels followed by a short ammonium chloride loading test in patients with levels above 6.0. In 14 patients (12.7%) a renal acidification defect was noted...... RTA in renal stone formers. Regardless of whether the acidification defect is primary or secondary to stone formation, however, all renal stone formers with distal RTA can expect to benefit from prophylactic alkaline therapy and it is recommended that the screening procedure, which is easy to use...

  12. Modeling of an immobilized lipase tubular reactor for the production of glycerol and fatty acids from oils; Modelado de un reactor tubular de lipasas inmovilizadas para la produccion de glicerol y acidos grasos a partir de aceites

    Energy Technology Data Exchange (ETDEWEB)

    Oddone, S.; Grasselli, M.; Cuellas, A.

    2010-07-01

    Advances in the design of a bioreactor in the fats and oils industry have permitted the hydrolysis of triglycerides in mild conditions and improved productivity while avoiding the formation of unwanted byproducts. The present work develops a mathematical model that describes the hydrolytic activity of a tubular reactor with immobilized lipases for the production of glycerol and fatty acids from the oil trade. Runge Kuttas numerical method of high order has been applied, considering that there is no accumulation of the substratum in the surface of the membrane, where the enzyme is. At the same time, different equations based on the kinetic model of Michaelis Mentens and the Ping-Pong bi-bi mechanism were examined. Experimental data in discontinuous systems are the basis for the development of the quantitative mathematical model that was used to simulate the process computationally. The obtained results allow for optimizing both the operative variables and the economic aspects of industrial processes. (Author)

  13. Novel biocompatible transversal pneumatic artificial muscles made of PDMS/PET satin composite

    Directory of Open Access Journals (Sweden)

    Szmechtyk Tomasz

    2016-06-01

    Full Text Available In this study novel transversal pneumatic artificial muscles (TPAM, made from composite – poly(dimethylsiloxane (PDMS matrix membrane and poly(ethylene terephthalate (PET satin reinforcement, are presented. Miniature TPAM consists of a flexible internal braid (IB reinforcing the membrane and the external braid (EB. EB, with fibers arranged transversely to the IB, is placed laterally. Differently prepared TPAMs were tested for their effectiveness as actuators for robot drive and the PDMS/PET composite suitability was evaluated for applications in human gastrointestinal tract (chemical resistance, thermal characteristic. FT-IR spectra of the composite were compared for study PDMS impregnation process of PET satin and effect of immersion in selected solution. The composite shows outstanding biocompatibility and the muscles have competitive static load characteristics in comparison with other pneumatic artificial muscles (PAM. These results lead to believe, that in the near future painless examination of the gastrointestinal tract using a secure robot will be possible.

  14. Toxicological significance of renal Bcrp: Another potential transporter in the elimination of mercuric ions from proximal tubular cells

    Energy Technology Data Exchange (ETDEWEB)

    Bridges, Christy C., E-mail: bridges_cc@mercer.edu; Zalups, Rudolfs K.; Joshee, Lucy

    2015-06-01

    Secretion of inorganic mercury (Hg{sup 2+}) from proximal tubular cells into the tubular lumen has been shown to involve the multidrug resistance-associated protein 2 (Mrp2). Considering similarities in localization and substrate specificity between Mrp2 and the breast cancer resistance protein (Bcrp), we hypothesize that Bcrp may also play a role in the proximal tubular secretion of mercuric species. In order to test this hypothesis, the uptake of Hg{sup 2+} was examined initially using inside-out membrane vesicles containing Bcrp. The results of these studies suggest that Bcrp may be capable of transporting certain conjugates of Hg{sup 2+}. To further characterize the role of Bcrp in the handling of mercuric ions and in the induction of Hg{sup 2+}-induced nephropathy, Sprague–Dawley and Bcrp knockout (bcrp{sup −/−}) rats were exposed intravenously to a non-nephrotoxic (0.5 μmol·kg{sup −1}), a moderately nephrotoxic (1.5 μmol·kg{sup −1}) or a significantly nephrotoxic (2.0 μmol·kg{sup −1}) dose of HgCl{sub 2}. In general, the accumulation of Hg{sup 2+} was greater in organs of bcrp{sup −/−} rats than in Sprague–Dawley rats, suggesting that Bcrp may play a role in the export of Hg{sup 2+} from target cells. Within the kidney, cellular injury and necrosis was more severe in bcrp{sup −/−} rats than in controls. The pattern of necrosis, which was localized in the inner cortex and the outer stripe of the outer medulla, was significantly different from that observed in Mrp2-deficient animals. These findings suggest that Bcrp may be involved in the cellular export of select mercuric species and that its role in this export may differ from that of Mrp2. - Highlights: • Bcrp may mediate transport of mercury out of proximal tubular cells. • Hg-induced nephropathy was more severe in Bcrp knockout rats. • Bcrp and Mrp2 may differ in their ability to transport Hg.

  15. Transverse and longitudinal angular momenta of light

    Energy Technology Data Exchange (ETDEWEB)

    Bliokh, Konstantin Y., E-mail: k.bliokh@gmail.com [Center for Emergent Matter Science, RIKEN, Wako-shi, Saitama 351-0198 (Japan); Nonlinear Physics Centre, RSPhysE, The Australian National University, Canberra, ACT 0200 (Australia); Nori, Franco [Center for Emergent Matter Science, RIKEN, Wako-shi, Saitama 351-0198 (Japan); Physics Department, University of Michigan, Ann Arbor, MI 48109-1040 (United States)

    2015-08-26

    We review basic physics and novel types of optical angular momentum. We start with a theoretical overview of momentum and angular momentum properties of generic optical fields, and discuss methods for their experimental measurements. In particular, we describe the well-known longitudinal (i.e., aligned with the mean momentum) spin and orbital angular momenta in polarized vortex beams. Then, we focus on the transverse (i.e., orthogonal to the mean momentum) spin and orbital angular momenta, which were recently actively discussed in theory and observed in experiments. First, the recently-discovered transverse spin  angular momenta appear in various structured fields: evanescent waves, interference fields, and focused beams. We show that there are several kinds of transverse spin angular momentum, which differ strongly in their origins and physical properties. We describe extraordinary features of the transverse optical spins and overview recent experiments. In particular, the helicity-independent transverse spin inherent in edge evanescent waves offers robust spin–direction coupling at optical interfaces (the quantum spin Hall effect of light). Second, we overview the transverse orbital angular momenta of light, which can be both extrinsic and intrinsic. These two types of the transverse orbital angular momentum are produced by spatial shifts of the optical beams (e.g., in the spin Hall effect of light) and their Lorentz boosts, respectively. Our review is underpinned by a unified theory of the angular momentum of light based on the canonical momentum and spin densities, which avoids complications associated with the separation of spin and orbital angular momenta in the Poynting picture. It allows us to construct a comprehensive classification of all known optical angular momenta based on their key parameters and main physical properties.

  16. Layer Control of Tubular Graphene for Corrosion Inhibition of Nickel Wires.

    Science.gov (United States)

    Nguyen, An T; Lai, Wei-Cheng; To, Bao Dong; Nguyen, Duc Dung; Hsieh, Ya-Ping; Hofmann, Mario; Kan, Hung-Chih; Hsu, Chia-Chen

    2017-07-12

    Corrosion protection of complex surface is an active area of research due to its importance to commercial applications such as electrochemical fabrication. However, conventional coatings exhibit limited conductivity, thermal stability, and durability and are thus not suitable. Recent work has shown the potential of graphene, a two-dimensional carbon allotrope, for corrosion protection. The studies, however, limited themselves to simple planar geometries that provide limited insight in the applicability to relevant morphologies such as mesh electrodes and roughened surfaces. We here study the corrosion protection ability of tubular graphene (TG) on Ni-wires as a model system for such complex geometries. TG-covered Ni wires of approximately 50 μm diameters were produced by the annealing of cellulose acetate (CA) on Ni. The high quality of the TG coating was confirmed by Raman spectroscopy, scanning electron microscopy, and electrical measurements. We show that the graphene layer number could be controlled by adjusting the CA membrane quantity. We found a direct relation between the degree of corrosion inhibition with the variation of graphene layer number. The increase of graphene layers on a Ni surface could enhance its corrosion inhibition in acidic, basic, and marine environments, which shows the potential of our approach for future applications.

  17. Ceramide-Induced Apoptosis in Renal Tubular Cells: A Role of Mitochondria and Sphingosine-1-Phoshate

    Science.gov (United States)

    Ueda, Norishi

    2015-01-01

    Ceramide is synthesized upon stimuli, and induces apoptosis in renal tubular cells (RTCs). Sphingosine-1 phosphate (S1P) functions as a survival factor. Thus, the balance of ceramide/S1P determines ceramide-induced apoptosis. Mitochondria play a key role for ceramide-induced apoptosis by altered mitochondrial outer membrane permeability (MOMP). Ceramide enhances oligomerization of pro-apoptotic Bcl-2 family proteins, ceramide channel, and reduces anti-apoptotic Bcl-2 proteins in the MOM. This process alters MOMP, resulting in generation of reactive oxygen species (ROS), cytochrome C release into the cytosol, caspase activation, and apoptosis. Ceramide regulates apoptosis through mitogen-activated protein kinases (MAPKs)-dependent and -independent pathways. Conversely, MAPKs alter ceramide generation by regulating the enzymes involving ceramide metabolism, affecting ceramide-induced apoptosis. Crosstalk between Bcl-2 family proteins, ROS, and many signaling pathways regulates ceramide-induced apoptosis. Growth factors rescue ceramide-induced apoptosis by regulating the enzymes involving ceramide metabolism, S1P, and signaling pathways including MAPKs. This article reviews evidence supporting a role of ceramide for apoptosis and discusses a role of mitochondria, including MOMP, Bcl-2 family proteins, ROS, and signaling pathways, and crosstalk between these factors in the regulation of ceramide-induced apoptosis of RTCs. A balancing role between ceramide and S1P and the strategy for preventing ceramide-induced apoptosis by growth factors are also discussed. PMID:25751724

  18. Numerical Investigation of the FSI Characteristics in a Tubular Pump

    Directory of Open Access Journals (Sweden)

    Shuo Wang

    2017-01-01

    Full Text Available Flow condition was simulated in a shaft tubular pump by using the Shear-Stress Transport (SST k-ω turbulence model with high quality structured grids in design condition. Corresponding structural vibration characteristics were then analyzed based on two-way coupled Fluid-Structure Interaction (FSI method. Fluid results showed that flow in the outlet flow passage was a combination of the axial flow and circumferential rotation motion. Time and frequency domain analysis of pressure pulsation of typical measure points indicated that larger pulsation amplitudes appeared in the tip of the blades and the main vibration source was the pressure pulsation induced by rotation of the blades. The fluid pulsation amplitudes decreased gradually along the flow direction, which can be ascribed to the function of fixed guide vane. Structural analysis of the blades in both pressure and suction side indicated that significant stress concentration was formed at the blade and hub connection near the leading edge. Maximum effective stress of the blades varied periodically, so prevention measures of the fatigue of blades should be taken. This research can provide important reference for the design of the tubular pump.

  19. Dynamic modeling of temperature change in outdoor operated tubular photobioreactors.

    Science.gov (United States)

    Androga, Dominic Deo; Uyar, Basar; Koku, Harun; Eroglu, Inci

    2017-07-01

    In this study, a one-dimensional transient model was developed to analyze the temperature variation of tubular photobioreactors operated outdoors and the validity of the model was tested by comparing the predictions of the model with the experimental data. The model included the effects of convection and radiative heat exchange on the reactor temperature throughout the day. The temperatures in the reactors increased with increasing solar radiation and air temperatures, and the predicted reactor temperatures corresponded well to the measured experimental values. The heat transferred to the reactor was mainly through radiation: the radiative heat absorbed by the reactor medium, ground radiation, air radiation, and solar (direct and diffuse) radiation, while heat loss was mainly through the heat transfer to the cooling water and forced convection. The amount of heat transferred by reflected radiation and metabolic activities of the bacteria and pump work was negligible. Counter-current cooling was more effective in controlling reactor temperature than co-current cooling. The model developed identifies major heat transfer mechanisms in outdoor operated tubular photobioreactors, and accurately predicts temperature changes in these systems. This is useful in determining cooling duty under transient conditions and scaling up photobioreactors. The photobioreactor design and the thermal modeling were carried out and experimental results obtained for the case study of photofermentative hydrogen production by Rhodobacter capsulatus, but the approach is applicable to photobiological systems that are to be operated under outdoor conditions with significant cooling demands.

  20. Dynamic model of microalgal production in tubular photobioreactors.

    Science.gov (United States)

    Fernández, I; Acién, F G; Fernández, J M; Guzmán, J L; Magán, J J; Berenguel, M

    2012-12-01

    A dynamic model for microalgal culture is presented. The model takes into account the fluid-dynamic and mass transfer, in addition to biological phenomena, it being based on fundamental principles. The model has been calibrated and validated using data from a pilot-scale tubular photobioreactor but it can be extended to other designs. It can be used to determine, from experimental measurements, the values of characteristic parameters. The model also allows a simulation of the system's dynamic behaviour in response to solar radiation, making it a useful tool for design and operation optimization of photobioreactors. Moreover, the model permits the identification of local pH gradients, dissolved oxygen and dissolved carbon dioxide; that can damage microalgae growth. In addition, the developed model can map the different characteristic time scales of phenomena inside microalgae cultures within tubular photobioreactors, meaning it is a valuable tool in the development of advanced control strategies for microalgae cultures. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Nano-tubular cellulose for bioprocess technology development.

    Science.gov (United States)

    Koutinas, Athanasios A; Sypsas, Vasilios; Kandylis, Panagiotis; Michelis, Andreas; Bekatorou, Argyro; Kourkoutas, Yiannis; Kordulis, Christos; Lycourghiotis, Alexis; Banat, Ibrahim M; Nigam, Poonam; Marchant, Roger; Giannouli, Myrsini; Yianoulis, Panagiotis

    2012-01-01

    Delignified cellulosic material has shown a significant promotional effect on the alcoholic fermentation as yeast immobilization support. However, its potential for further biotechnological development is unexploited. This study reports the characterization of this tubular/porous cellulosic material, which was done by SEM, porosimetry and X-ray powder diffractometry. The results showed that the structure of nano-tubular cellulose (NC) justifies its suitability for use in "cold pasteurization" processes and its promoting activity in bioprocessing (fermentation). The last was explained by a glucose pump theory. Also, it was demonstrated that crystallization of viscous invert sugar solutions during freeze drying could not be otherwise achieved unless NC was present. This effect as well as the feasibility of extremely low temperature fermentation are due to reduction of the activation energy, and have facilitated the development of technologies such as wine fermentations at home scale (in a domestic refrigerator). Moreover, NC may lead to new perspectives in research such as the development of new composites, templates for cylindrical nano-particles, etc.

  2. Advances in tubular solid oxide fuel cell technology

    Energy Technology Data Exchange (ETDEWEB)

    Singhal, S.C. [Westinghouse Electric Corp., Pittsburgh, PA (United States)

    1996-12-31

    The design, materials and fabrication processes for the earlier technology Westinghouse tubular geometry cell have been described in detail previously. In that design, the active cell components were deposited in the form of thin layers on a ceramic porous support tube (PST). The tubular design of these cells and the materials used therein have been validated by successful electrical testing for over 65,000 h (>7 years). In these early technology PST cells, the support tube, although sufficiently porous, presented an inherent impedance to air flow toward air electrode. In order to reduce such impedance to air flow, the wall thickness of the PST was first decreased from the original 2 mm (the thick-wall PST) to 1.2 mm (the thin-wall PST). The calcia-stabilized zirconia support tube has now been completely eliminated and replaced by a doped lanthanum manganite tube in state-of-the-art SOFCs. This doped lanthanum manganite tube is extruded and sintered to about 30 to 35 percent porosity, and serves as the air electrode onto which the other cell components are fabricated in thin layer form. These latest technology cells are designated as air electrode supported (AES) cells.

  3. Understanding shape and morphology of unusual tubular starch nanocrystals.

    Science.gov (United States)

    Gong, Bei; Liu, Wenxia; Tan, Hua; Yu, Dehai; Song, Zhaoping; Lucia, Lucian A

    2016-10-20

    Starch nanocrystals (SNC) are aptly described as the insoluble degradation byproducts of starch granules that purportedly display morphologies that are platelet-like, round, square, and oval-like. In this work, we reported the preparation of SNC with unprecedented tubular structures through sulfuric acid hydrolysis of normal maize starch, subsequent exposure to ammonia and relaxation at 4°C. High-resolution transmission electron microscopy observation clearly proved that the SNCs possess tubular nanostructures with polygonal cross-section. After further reviewing the transformations of SNC by acid hydrolysis, ammonia treatment, and curing time at 4°C, a mechanism for T-SNC formation is suggested. It is conjectured that T-SNC gradually self-assembles by combination of smaller platelet-like/square nanocrystals likely loosely aggregated by starch molecular chains from residual amorphous regions. This work paves the way for the pursuit of new approaches for the preparation of starch-based nanomaterials possessing unique morphologies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Carbohydrates in Ankistrodesmus braunii biomass cultivated in tubular photobioreactors

    Directory of Open Access Journals (Sweden)

    Ana Lucía Morocho-Jácome

    2017-12-01

    Full Text Available The great need for microalgae biomass production in tubular photobioreactors has increased for use in biofuels, pharmaceuticals and even cosmetic applications. In order to better understand the potential applications of this material, it is imperative to know in detail its composition. Ankistrodesmus braunii was cultivated in 3.5 L tubular air-lift photobioreactors using 10 mM sodium nitrate as nitrogen source in batch mode at 60 µmol photons m-2 s-1. The maximum biomass concentration (Xm and the biomass productivity (PX reached at 6th day of cultivation was 1249 ± 72 mg L-1 and 165 ± 13 mg L-1 d-1, respectively. Carbohydrates productivity expressed in terms of glucose, galactose and glucose+galactose (1:1 were 2.57 ± 0.04, 4.12 ± 0.06 and 3.22 ± 0.05 mg L-1 d-1, respectively. Results show a statistical difference that was found between carbohydrate productivity values expressed as glucose, galactose and glucose+galactose (1:1.

  5. Nano-tubular cellulose for bioprocess technology development.

    Directory of Open Access Journals (Sweden)

    Athanasios A Koutinas

    Full Text Available Delignified cellulosic material has shown a significant promotional effect on the alcoholic fermentation as yeast immobilization support. However, its potential for further biotechnological development is unexploited. This study reports the characterization of this tubular/porous cellulosic material, which was done by SEM, porosimetry and X-ray powder diffractometry. The results showed that the structure of nano-tubular cellulose (NC justifies its suitability for use in "cold pasteurization" processes and its promoting activity in bioprocessing (fermentation. The last was explained by a glucose pump theory. Also, it was demonstrated that crystallization of viscous invert sugar solutions during freeze drying could not be otherwise achieved unless NC was present. This effect as well as the feasibility of extremely low temperature fermentation are due to reduction of the activation energy, and have facilitated the development of technologies such as wine fermentations at home scale (in a domestic refrigerator. Moreover, NC may lead to new perspectives in research such as the development of new composites, templates for cylindrical nano-particles, etc.

  6. Rhabdomyolysis with acute tubular necrosis following occupational inhalation of thinners.

    Science.gov (United States)

    Ngajilo, D; Ehrlich, R

    2017-07-01

    Thinners are mixtures of organic solvents commonly containing toluene, xylene, acetone, hexane, benzene and methyl isobutyl ketone. This report describes a case of rhabdomyolysis with acute tubular necrosis and renal failure, most likely attributable to toluene, following occupational exposure to thinners while cleaning a steel water tank. These adverse health effects have previously been reported following acute poisoning or intentional inhalation by drug abusers, but rarely in the occupational setting. Poor working conditions, lack of health and safety training and delayed treatment contributed to the onset and severity of the patient's complications. This case emphasizes the need for strict control measures, including adequate ventilation, training on working in confined spaces, appropriate personal protective equipment and emergency rescue procedures in such settings. In addition, rhabdomyolysis, acute tubular necrosis and renal failure should be added to safety data material as possible complications of excessive inhalation of thinners. © The Author 2017. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Performance of Serum Creatinine and Kidney Injury Biomarkers for Diagnosing Histologic Acute Tubular Injury.

    Science.gov (United States)

    Moledina, Dennis G; Hall, Isaac E; Thiessen-Philbrook, Heather; Reese, Peter P; Weng, Francis L; Schröppel, Bernd; Doshi, Mona D; Wilson, F Perry; Coca, Steven G; Parikh, Chirag R

    2017-12-01

    The diagnosis of acute kidney injury (AKI), which is currently defined as an increase in serum creatinine (Scr) concentration, provides little information on the condition's actual cause. To improve phenotyping of AKI, many urinary biomarkers of tubular injury are being investigated. Because AKI cases are not frequently biopsied, the diagnostic accuracy of concentrations of Scr and urinary biomarkers for histologic acute tubular injury is unknown. Cross-sectional analysis from multicenter prospective cohort. Hospitalized deceased kidney donors on whom kidney biopsies were performed at the time of organ procurement for histologic evaluation. (1) AKI diagnosed by change in Scr concentration during donor hospitalization and (2) concentrations of urinary biomarkers (neutrophil gelatinase-associated lipocalin [NGAL], liver-type fatty acid-binding protein [L-FABP], interleukin 18 [IL-18], and kidney injury molecule 1 [KIM-1]) measured at organ procurement. Histologic acute tubular injury. Of 581 donors, 98 (17%) had mild acute tubular injury and 57 (10%) had severe acute tubular injury. Overall, Scr-based AKI had poor diagnostic performance for identifying histologic acute tubular injury and 49% of donors with severe acute tubular injury did not have AKI. The area under the receiver operating characteristic curve (AUROC) of change in Scr concentration for diagnosing severe acute tubular injury was 0.58 (95% CI, 0.49-0.67) and for any acute tubular injury was 0.52 (95% CI, 0.45-0.58). Compared with Scr concentration, NGAL concentration demonstrated higher AUROC for diagnosing both severe acute tubular injury (0.67; 95% CI, 0.60-0.74; P=0.03) and any acute tubular injury (0.60; 95% CI, 0.55-0.66; P=0.005). In donors who did not have Scr-based AKI, NGAL concentrations were higher with increasing severities of acute tubular injury (subclinical AKI). However, compared with Scr concentration, AUROCs for acute tubular injury diagnosis were not significantly higher for urinary L

  8. Efficiency and temperature dependence of water removal by membrane dryers

    Science.gov (United States)

    Leckrone, K. J.; Hayes, J. M.

    1997-01-01

    The vapor pressure of water in equilibrium with sorption sites within a Nafion membrane is given by log P(WN) = -3580/T + 10.01, where P(WN) is expressed in Torr and T is the membrane temperature, in kelvin. The efficiency of dryers based on selective permeation of water through Nafion can thus be enhanced by cooling the membrane. Residual water in effluents exceeds equilibrium levels if insufficient time is allowed for water to diffuse to the membrane surface as gas passes through the dryer. For tubular configurations, this limitation can be avoided if L > or = Fc(10(3.8)/120 pi D), where L is the length of the tubular membrane, in centimeters, Fc is the gas flow rate, in mL/ min, and D is the diffusion coefficient for water in the carrier gas at the operating temperature of the dryer, in cm2/s. An efficient dryer that at room temperature dries gas to a dew point of -61 degrees C is described; the same dryer maintained at 0 degrees C yields a dew point of -80 degrees C and removes water as effectively as Mg(ClO4)2 or a dry ice/acetone slush. The use of Nafion membranes to construct devices capable of delivering gas streams with low but precisely controlled humidities is discussed.

  9. Comparison of extended hemicolectomy versus transverse colectomy in patients with cancer of the transverse colon.

    Science.gov (United States)

    van Rongen, I; Damhuis, R A M; van der Hoeven, J A B; Plaisier, P W

    2013-01-01

    Cancer of the transverse colon is rare and postoperative mortality tends to be high. Standard surgical treatment involves either extended hemicolectomy or transverse colectomy, depending on the location of the tumour. The aim of the present study was to compare postoperative mortality and five-year survival between these types of surgery. For this observational study, data on patients with a tumour of the transverse colon, treated by open resection in the Dordrecht Hospital from 1989 through 2003, were derived from the database of the regional cancer registry. Information on type of resection, tumour stage, complications, postoperative mortality (30-day) and survival was abstracted from the medical files. Patients with multi-organ surgery, (sub)total colectomy or stage IV disease were excluded from the analysis, leaving a total series of 103 patients. Transverse colectomy comprised one third of operations, predominantly involving partial resections. Postoperative mortality was 6% (2/34) after transverse colectomy and 7% (5/69) after extended hemicolectomy. Five-year survival was slightly higher for the hemicolectomy group (61% versus 50%), but this difference did not reach statistical significance (p = 0.34). Our results confirm the high postoperative risk after surgery for cancer of the transverse colon and show that this risk does not depend on the type of surgery. Considering the satisfactory results after partial transverse colectomy, segmental resections may be considered as an option for the treatment of localised tumours of the transverse colon.

  10. Proximal Renal Tubular Acidosis Mediated by Mutations in NBCe1-A: Unraveling the Transporter’s Structure-Functional Properties

    Directory of Open Access Journals (Sweden)

    Ira eKurtz

    2013-12-01

    Full Text Available NBCe1 belongs to the SLC4 family of base transporting membrane proteins that plays a significant role in renal, extrarenal, and systemic acid-base homeostasis. Recent progress has been made in characterizing the structure-function properties of NBCe1 (encoded by the SLC4A4 gene, and those factors that regulate its function. In the kidney, the NBCe1-A variant that is expressed on the basolateral membrane of proximal tubule is the key transporter responsible for overall transepithelial bicarbonate absorption in this nephron segment. NBCe1 mutations impair transepithelial bicarbonate absorption causing the syndrome of proximal renal tubular acidosis (pRTA. Studies of naturally occurring NBCe1 mutant proteins in heterologous expression systems have been very helpful in elucidation the structure-functional properties of the transporter. NBCe1 mutations are now known to cause pRTA by various mechanisms including the alteration of the transporter function (substrate ion interaction, electrogenicity, abnormal processing to the plasma membrane, and a perturbation in its structural properties. The elucidation of how NBCe1 mutations cause pRTA in addition to the recent studies which have provided further insight into the topology of the transporter have played an important role in uncovering its critically important structural-function properties.

  11. Possibilities for reduction of transverse projected emittances by partial removal of transverse to longitudinal beam correlations

    International Nuclear Information System (INIS)

    Balandin, V.; Decking, W.; Golubeva, N.

    2014-09-01

    We show that if in the particle beam there are linear correlations between energy of particles and their transverse positions and momenta (linear beam dispersions), then the transverse projected emittances always can be reduced by letting the beam to pass through magnetostatic system with specially chosen nonzero lattice dispersions. The maximum possible reduction of the transverse projected emittances occurs when all beam dispersions are zeroed, and the values of the lattice dispersions required for that are completely defined by the values of the beam dispersions and the beam rms energy spread and are independent from any other second-order central beam moments. Besides that, we prove that, alternatively, one can also use the lattice dispersions to remove linear correlations between longitudinal positions of particles and their transverse coordinates (linear beam tilts), but in this situation solution for the lattice dispersions is nonunique and the reduction of the transverse projected emittances is not guaranteed.

  12. Spin versus helicity in processes involving transversity

    CERN Document Server

    Mekhfi, Mustapha

    2011-01-01

    We construct the spin formalism in order to deal in a direct and natural way with processes involving transversity which are now of increasing popularity. The helicity formalism which is more appropriate for collision processes of definite helicity has been so far used also to manage processes with transversity, but at the price of computing numerous helicity amplitudes generally involving unnecessary kinematical variables.In a second step we work out the correspondence between both formalisms and retrieve in another way all results of the helicity formalism but in simpler forms.We then compute certain processes for comparison.A special process:the quark dipole magnetic moment is shown to be exclusively treated within the spin formalism as it is directly related to the transverse spin of the quark inside the baryon.

  13. Transversely Compressed- and Restrained Shear Joints

    DEFF Research Database (Denmark)

    Schmidt, Jacob Wittrup; Hansen, Christian Skodborg

    2013-01-01

    Anchorage of FRP strengthening systems where the deformation perpendicular to the FRP material is restrained or a compressive force is applied on the strengthening, seems to provide ductility, increased utilization of the FRP and failure modes which can be controlled through the anchorage method....... This paper presents theoretical model which can predict the response of transversely compressed and restrained single- and double lap shear joints. The interface material model is based on a cohesive law in the shear-slip plane with a descending branch and a uniform frictional stress added due...... to the friction in the crack, emanating from the transverse pressure or restraint. The theoretical model is compared with experimental results from transversely compressed single- and double shear joints. Also theoretical predictions of a mechanical integrated sleeve-wedge anchorage load capacity are carried out...

  14. Associated transverse energy in hadronic jet production

    International Nuclear Information System (INIS)

    Marchesini, G.; Webber, B.R.

    1988-01-01

    We present a theoretical study of the ''pedestal height'' in hadronic jet production, i.e., the mean transverse energy per unit of rapidity accompanying a high-transverse-energy jet. We find that perturbative QCD, supplemented by a Monte Carlo estimate of higher-order corrections and a soft underlying event structure similar to that of minimum-bias collisions, can account for the observed pedestal height and its dependence on jet transverse energy. We propose a way of separating the hard pedestal contribution from that of the underlying event by measuring the quantity , which is one-half the absolute difference of the pedestal heights on the two sides of the jet. This quantity is dominated by the hard QCD component, whereas = - is dominated by the soft underlying event. We also discuss the differential distribution of pedestal height and the charged multiplicity in the pedestal

  15. Membrane paradigm

    International Nuclear Information System (INIS)

    Price, R.H.; Thorne, K.S.

    1986-01-01

    The membrane paradigm is a modified frozen star approach to modeling black holes, with particles and fields assuming a complex, static, boundary-layer type structure (membrane) near the event horizon. The membrane has no effects on the present or future evolution of particles and fields above itself. The mathematical representation is a combination of a formalism containing terms for the shear and bulk viscosity, surface pressure, momentum, temperature, entropy, etc., of the horizon and the 3+1 formalism. The latter model considers a family of three-dimensional spacelike hypersurfaces in one-dimensional time. The membrane model considers a magnetic field threading the hole and undergoing torque from the hole rotation. The field is cleaned by the horizon and distributed over the horizon so that ohmic dissipation is minimized. The membrane paradigm is invalid inside the horizon, but is useful for theoretically probing the properties of slowly evolving black holes

  16. Membrane processes

    Science.gov (United States)

    Staszak, Katarzyna

    2017-11-01

    The membrane processes have played important role in the industrial separation process. These technologies can be found in all industrial areas such as food, beverages, metallurgy, pulp and paper, textile, pharmaceutical, automotive, biotechnology and chemical industry, as well as in water treatment for domestic and industrial application. Although these processes are known since twentieth century, there are still many studies that focus on the testing of new membranes' materials and determining of conditions for optimal selectivity, i. e. the optimum transmembrane pressure (TMP) or permeate flux to minimize fouling. Moreover the researchers proposed some calculation methods to predict the membrane processes properties. In this article, the laboratory scale experiments of membrane separation techniques, as well their validation by calculation methods are presented. Because membrane is the "heart" of the process, experimental and computational methods for its characterization are also described.

  17. Preservation of paraspinal muscle after transmuscular approach using a tubular retractor for lumbar decompression surgery

    Directory of Open Access Journals (Sweden)

    Toshiya Tachibana, MD, PhD

    2017-09-01

    Conclusion: The preservation of paraspinal muscle was greater in patients with a tubular retractor than with the subperiosteal approach. Detaching the paraspinal muscle from the lamina may cause partial denervation of the paraspinal muscle and muscle atrophy. Therefore, the transmuscular approach using a tubular retractor may be a less invasive approach for the preservation of paraspinal muscle.

  18. On Energy Balance and Production Costs in Tubular and Flat Panel Photobioreactors

    NARCIS (Netherlands)

    Norsker, N.H.; Barbosa, M.J.; Vermue, M.H.; Wijffels, R.H.

    2012-01-01

    Reducing mixing in both flat panel and tubular photobioreactors can result in a positive net energy balance with state-of-the-art technology and Dutch weather conditions. In the tubular photobioreactor, the net energy balance becomes positive at velocities <0.3 ms-1, at which point the biomass

  19. Spectrum of mutations in the renin-angiotensin system genes in autosomal recessive renal tubular dysgenesis

    DEFF Research Database (Denmark)

    Gribouval, Olivier; Morinière, Vincent; Pawtowski, Audrey

    2012-01-01

    Autosomal recessive renal tubular dysgenesis (RTD) is a severe disorder of renal tubular development characterized by early onset and persistent fetal anuria leading to oligohydramnios and the Potter sequence, associated with skull ossification defects. Early death occurs in most cases from anuri...

  20. 46 CFR 154.1320 - Sighting ports, tubular gauge glasses, and flat plate type gauge glasses.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Sighting ports, tubular gauge glasses, and flat plate type gauge glasses. 154.1320 Section 154.1320 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... LIQUEFIED GASES Design, Construction and Equipment Instrumentation § 154.1320 Sighting ports, tubular gauge...

  1. Effect of cisplatin on renal haemodynamics and tubular function in the dog kidney

    DEFF Research Database (Denmark)

    Daugaard, G; Abildgaard, U; Holstein-Rathlou, N H

    1987-01-01

    Administration of cisplatin (5 mg/kg) to dogs results in polyuric renal failure due initially to a proximal tubular functional impairment. 48-72 h after the cisplatin administration the depressed renal function can be attributed to impairment of proximal as well as distal tubular reabsorptive...

  2. SIDE-BY-SIDE TESTS OF DIFFERENTLY DESIGNED EVACUATED TUBULAR COLLECTORS

    DEFF Research Database (Denmark)

    Fan, Jianhua; Dragsted, Janne; Furbo, Simon

    2007-01-01

    Six differently designed evacuated tubular collectors, ETCs, utilizing solar radiation from all directions, have been investigated experimentally. The evacuated tubular solar collectors investigated include one SLL all-glass ETC from Tshinghua Solar Co., four heat pipe ETCs from Sunda Technolgoy Co...

  3. Endogenous versus exogenous lithium clearance for evaluation of dopamine-induced changes in renal tubular function

    DEFF Research Database (Denmark)

    Olsen, Niels Vidiendal; Fogh-Andersen, N; Strandgaard, S

    1996-01-01

    1. The present randomized, double-blind cross-over study compared endogenous and exogenous lithium clearance (CLi) for estimation of the effect of dopamine on tubular sodium reabsorption. Twelve normal, salt-repleted male subjects were investigated on three different occasions with either placebo...... that the two methods are interchangeable for estimation of dopamine-induced changes in tubular function....

  4. Behaviour of Steel Tubular Stub and Slender Columns in-filled with ...

    African Journals Online (AJOL)

    In this paper, an attempt was made with steel tubular columns in-filled with recycled aggregate concrete instead of normal conventional concrete so as to utilize the construction and demolition debris for effective recycling in construction works. The behaviour of circular and square concrete-filled steel tubular sections ...

  5. Gamma flux responsive self-powered detector with a tubular emitter

    International Nuclear Information System (INIS)

    Goldstein, N.P.; Todt, W.H.

    1982-01-01

    A gamma-sensitive flux detector comprises tubular emitter, an insulating core within the emitter and an insulating layer about the emitter, and a tubular conductive collector electrode about the insulating layer. The emitter material may be platinum, lead, bismuth, tantalum, tungsten; platinum preferred

  6. Tubular Carcinoma of the Breast: Advantages and Limitations of Breast Tomosynthesis

    Science.gov (United States)

    Rocha, Ana; Reis, Alcinda

    2016-01-01

    Tubular carcinoma of the breast is a rare variant of invasive ductal carcinoma. We report a case of 42-year-old asymptomatic female with a histopathological proven multifocal tubular carcinoma, studied by mammography, Tomosynthesis, Ultrasound, and Magnetic Resonance. Herein, we discuss the advantages and limitations of Tomosynthesis, an emerging imaging technique, in this particular case. PMID:28116205

  7. 78 FR 77420 - Certain Oil Country Tubular Goods From the Republic of Turkey: Preliminary Negative...

    Science.gov (United States)

    2013-12-23

    ... countervailable subsidies are being provided to the production or exportation of the subject merchandise in Turkey... International Trade Administration Certain Oil Country Tubular Goods From the Republic of Turkey: Preliminary... tubular goods (OCTG) from the Republic of Turkey (Turkey). The period of investigation is January 1, 2012...

  8. Operative Method for Transverse Colon Carcinoma: Transverse Colectomy Versus Extended Colectomy.

    Science.gov (United States)

    Chong, Choon Seng; Huh, Jung Wook; Oh, Bo Young; Park, Yoon Ah; Cho, Yong Beom; Yun, Seong Hyeon; Kim, Hee Cheol; Lee, Woo Yong

    2016-07-01

    The type of surgery performed for primary transverse colon cancer varies based on tumor characteristics and surgeon perspective. The optimal oncological outcome following different surgical options has not been clearly established, and transverse colectomy has shown oncological equivalence only in small cohort studies. Our aim was to compare long-term oncological outcomes after transverse colectomy versus extended resection for transverse colon cancer. This study is a retrospective review of prospectively collected data. This study was conducted at a tertiary care hospital. All patients treated for transverse colon cancer at the Samsung Medical Center between 1995 and 2013 were included. Oncological outcomes were compared between 2 groups of patients: a transverse colectomy group and an extended colectomy group (which included extended right hemicolectomy and left hemicolectomy). A total of 1066 patients were included, of whom 750 (70.4%) underwent extended right hemicolectomy, 127 (11.9%) underwent transverse colectomy, and 189 (17.7%) underwent left hemicolectomy. According to univariate analysis, surgical approach, histological type, tumor morphology, cancer T and N stage, cancer size, and lymphovascular invasion were significant factors contributing to disease-free survival (DFS). However, as seen in multivariate analysis, only node-positive disease (HR = 2.035 (1.188-3.484)), tumors with ulcerative morphology (HR = 3.643 (1.132-11.725)), and the presence of vascular invasion (HR = 2.569 (1.455-4.538)) were significant factors for DFS. Further analysis with a propensity-matched cohort between the transverse and extended colectomy groups demonstrated no significant differences in DFS and overall survival. This study was limited because it was performed at a single institution and it was retrospective in nature. In terms of perioperative and oncological outcomes, transverse colectomy and extended colectomy did not differ despite a shorter specimen length and

  9. PENGURANGAN KADAR CO2 MENGGUNAKAN SPIRULINA PLATENSIS DALAM TUBULAR BIOREACTOR

    Directory of Open Access Journals (Sweden)

    Zainal Syam Arifin

    2015-06-01

    Full Text Available Increasing the population impact on increasing energy demand. On the other hand, the energy generation industry has been blamed as one of the contributors of carbon dioxide about 25% of total CO2 emissions worldwide. Meanwhile, the production of biogas, which aims to address the increasing need of energy, produces carbon dioxide in the range of 25–50% by volume. To overcome this, a cheap method, optimum and efficient as well as environmentally friendly in reducing CO2 levels by using Spirulina platensis is needed. This research aims to created a mathematical models and found the optimum flow rate to reduced levels of CO2 by using Spirulina platensis. This study used a glass tubular bioreactor (D = 2.6 cm at a temperature of 30°C and irradiated with a fluorescent lamp Philips TL 36 Watt, color temperature: 6,200K cool daylight, light output: 2,600 lm, 72 lm/W. Tubular reactor was placed in a box lined with silver foil walls on three sides. With mathematical models of tubular reactor, the reaction rate constants could be predicted. Based on calculations of data and graphs, optimum volumetric velocity could also be predicted. Variation of flowrate to observed the reduction rate of CO2 was 0.25 mL/sec, 0.35 mL/sec, 0.5 mL/sec, 0.75 mL/sec, 1 mL/sec. Carbon source was 99.99% CO2.Observations of Spirulina growth was made on the flow rate of 0.25 mL/sec at the initial levels of dry weight 2.1208 g/L. The results of this study indicated that the low flowratewas a more effective way to reduced carbon dioxide levels using Spirulina platensis (= 2.82×10-4 sec-1. The highest conversion was obtained at a volumetric flow rate of 0.25 mL/sec and optimum speeds in the range of 0.3 to 0.4 mL/sec. The rate of incoming CO2 flux should be less than 0.047 mL/cm2.detik. Specific Growth Rate (µ of Spirulina platensis in this study was 2.56×10-2 minute-1.   Keywords: Spirulina platensis, a vertical tubular bioreactor, CO2 reduction     ABSTRAK

  10. Inclusive eta production at large transverse momenta

    International Nuclear Information System (INIS)

    Donaldson, G.J.; Gordon, H.A.; Lai, K.; Stumer, I.; Barnes, A.V.; Mellema, D.J.; Tollestrup, A.V.; Walker, R.L.; Dahl, O.; Johnson, R.; Ogawa, A.; Pripstein, M.; Shannon, S.

    1978-01-01

    We have measured the ratio of inclusive production of eta to π 0 at transverse momenta above 1.5 GeV/c. Results are presented for various meson and proton beams with momenta of 100, 200, and 300 GeV/c incident upon a hydrogen target. The eta/π 0 production ratio is found to be independent of incident beam momentum and of the transverse and longitudinal momenta of production. The ratio for pion- and proton-induced reactions is 0.44 +- 0.05; for kaons, it is 0.74 +- 0.12

  11. Transverse posterior element fractures associated with torsion

    International Nuclear Information System (INIS)

    Abel, M.S.

    1989-01-01

    Six examples of a previously undescribed class of transverse vertebral element fractures are presented. These fractures differ from Chance and Smith fractures and their variants in the following respects: (1) the etiology is torsion and not flexion; (2) there is neither distraction of posterior ring fragments nor posterior ligament tears; (3) in contrast to Chance and Smith fractures, extension of the fracture into the vertebral body is absent or minimal; (4) the transverse process of the lumbar vertebra is avulsed at its base with a vertical fracture, not split horizontally. These fractures occur in cervical, lumbar, and sacral vertebrae in normal or compromised areas of the spine. (orig.)

  12. Results on large transverse momentum phenomena

    CERN Document Server

    Büsser, F W; Blumenfeld, B; Camilleri, L L; Cool, R L; Di Lella, L; Gladding, G; Lederman, Leon Max; Litt, L; Placci, A; Pope, B G; Segler, S L; Smith, A M; Yoh, J K; Zavattini, E

    1973-01-01

    Preliminary results of an experiment on large transverse momentum phenomena performed at the CERN-ISR at centre-of-mass energies of 52.7 and 44.8 GeV are presented. The topics studied were the inclusive reaction p+p to pi /sup 0/+'anything', where the pi /sup 0/ was emitted around 90 degrees in the centre- of-mass system, ( pi /sup 0/ pi /sup 0/) correlations, and the charged multiplicity associated with large transverse momentum pi /sup 0/'s. In addition, results of a search for electrons and electron pairs are included. (4 refs).

  13. [The transversality and health promotion schools].

    Science.gov (United States)

    Gavidia Catalán, V

    2001-01-01

    The following article shows the evolution of the schools contribution to the Health Education of children and young people. Moving on from the traditional concept of health, today, Health Education has a general and global meaning, which encompasses all of the physical, psychological and social aspects of health. These aspects define the characteristics of the "Healthy School". The need to broach the "transversal subject" offers schools the possibility of developing "transversality" in the Health Education. Finally, the concept of promoting health defines, together with the other subjects, that which we understand by "the heath promotion schools", which attempts to progress the full integration of schools in the society in which they are located.

  14. Tubular oxide microcavity with high-index-contrast walls: Mie scattering theory and 3D confinement of resonant modes.

    Science.gov (United States)

    Wang, Jiao; Zhan, Tianrong; Huang, Gaoshan; Cui, Xugao; Hu, Xinhua; Mei, Yongfeng

    2012-08-13

    Tubular oxide optical microcavities with thin walls (Mie scattering theory. Novel material design and superior optical resonant properties in such self-rolled micro-tubular cavities promise many potential applications e.g. in optofluidic sensing and lasing.

  15. A quantitative description of tubular system Ca(2+) handling in fast- and slow-twitch muscle fibres.

    Science.gov (United States)

    Cully, Tanya R; Edwards, Joshua N; Murphy, Robyn M; Launikonis, Bradley S

    2016-06-01

    Current methods do not allow a quantitative description of Ca(2+) movements across the tubular (t-) system membrane without isolating the membranes from their native skeletal muscle fibre. Here we present a fluorescence-based method that allows determination of the t-system [Ca(2+) ] transients and derivation of t-system Ca(2+) fluxes in mechanically skinned skeletal muscle fibres. Differences in t-system Ca(2+) -handling properties between fast- and slow-twitch fibres from rat muscle are resolved for the first time using this new technique. The method can be used to study Ca(2+) handling of the t-system and allows direct comparisons of t-system Ca(2+) transients and Ca(2+) fluxes between groups of fibres and fibres from different strains of animals. The tubular (t-) system of skeletal muscle is an internalization of the plasma membrane that maintains a large Ca(2+) gradient and exchanges Ca(2+) between the extracellular and intracellular environments. Little is known of the Ca(2+) -handling properties of the t-system as the small Ca(2+) fluxes conducted are difficult to resolve with conventional methods. To advance knowledge in this area we calibrated t-system-trapped rhod-5N inside skinned fibres from rat and [Ca(2+) ]t-sys , allowing confocal measurements of Ca(2+) -dependent changes in rhod-5N fluorescence during rapid changes in the intracellular ionic environment to be converted to [Ca(2+) ] transients in the t-system ([Ca(2+) ]t-sys (t)). Furthermore, t-system Ca(2+) -buffering power was determined so that t-system Ca(2+) fluxes could be derived from [Ca(2+) ]t-sys (t). With this new approach, we show that rapid depletion of sarcoplasmic reticulum (SR) Ca(2+) induced a robust store-operated Ca(2+) entry (SOCE) in fast- and slow-twitch fibres, reducing [Ca(2+) ]t-sys to twitch fibres were greater than that in slow-twitch fibres. In addition, simultaneous imaging of t-system and SR Ca(2+) signals indicated that both membrane compartments accumulated Ca(2+) at

  16. A quantitative description of tubular system Ca2+ handling in fast‐ and slow‐twitch muscle fibres

    Science.gov (United States)

    Cully, Tanya R.; Edwards, Joshua N.; Murphy, Robyn M.

    2016-01-01

    Key points Current methods do not allow a quantitative description of Ca2+ movements across the tubular (t‐) system membrane without isolating the membranes from their native skeletal muscle fibre.Here we present a fluorescence‐based method that allows determination of the t‐system [Ca2+] transients and derivation of t‐system Ca2+ fluxes in mechanically skinned skeletal muscle fibres. Differences in t‐system Ca2+‐handling properties between fast‐ and slow‐twitch fibres from rat muscle are resolved for the first time using this new technique.The method can be used to study Ca2+ handling of the t‐system and allows direct comparisons of t‐system Ca2+ transients and Ca2+ fluxes between groups of fibres and fibres from different strains of animals. Abstract The tubular (t‐) system of skeletal muscle is an internalization of the plasma membrane that maintains a large Ca2+ gradient and exchanges Ca2+ between the extracellular and intracellular environments. Little is known of the Ca2+‐handling properties of the t‐system as the small Ca2+ fluxes conducted are difficult to resolve with conventional methods. To advance knowledge in this area we calibrated t‐system‐trapped rhod‐5N inside skinned fibres from rat and [Ca2+]t‐sys, allowing confocal measurements of Ca2+‐dependent changes in rhod‐5N fluorescence during rapid changes in the intracellular ionic environment to be converted to [Ca2+] transients in the t‐system ([Ca2+]t‐sys (t)). Furthermore, t‐system Ca2+‐buffering power was determined so that t‐system Ca2+ fluxes could be derived from [Ca2+]t‐sys (t). With this new approach, we show that rapid depletion of sarcoplasmic reticulum (SR) Ca2+ induced a robust store‐operated Ca2+ entry (SOCE) in fast‐ and slow‐twitch fibres, reducing [Ca2+]t‐sys to twitch fibres were greater than that in slow‐twitch fibres. In addition, simultaneous imaging of t‐system and SR Ca2+ signals indicated that both membrane

  17. Acute Tubular Necrosis and Interstitial Nephritis during Pemetrexed Therapy

    Directory of Open Access Journals (Sweden)

    Judith Michels

    2009-03-01

    Full Text Available We report a patient with unknown primary undifferentiated carcinoma who developed acute renal failure associated with interstitial fibrosis following pemetrexed therapy. Despite drug withdrawal, renal function remained altered and the patient experienced chronic renal insufficiency. Pemetrexed disodium (Alimta™ is a multitargeted antifolate agent approved by the Food and Drug Administration (FDA for patients diagnosed with mesothelioma and non-small cell lung cancer. This drug is almost exclusively cleared by renal excretion [1]. The most common side effects are hematologic dose-limiting toxicities and nonhematologic toxicities including fatigue, diarrhea, nausea, mucositis and rash. Although few cases of renal failure have been published, no study has reported on the renal pathological findings in this setting. We present a case of acute tubular necrosis associated with interstitial fibrosis after pemetrexed therapy.

  18. Amelogenesis imperfecta with distal renal tubular acidosis: A novel syndrome?

    Directory of Open Access Journals (Sweden)

    R A Misgar

    2017-01-01

    Full Text Available Amelogenesis imperfecta (AI is a heterogeneous group of inherited dental enamel defects. It has rarely been reported in association with multiorgan syndromes and metabolic disorders. The metabolic disorders that have been reported in association with AI include hypocalciuria, impaired urinary concentrating ability, and Bartter-like syndrome. In literature, only three cases of AI and distal renal tubular acidosis (dRTA have been described: two cases in adults and a solitary case in the pediatric age group. Here, we report a child with AI presenting with dRTA; to the best of our knowledge, our reported case is the only second such case in pediatric age group. Our case highlights the importance of recognizing the possibility of renal abnormalities in patients with AI as it will affect the long-term prognosis.

  19. [Diagnostic difficulties in a case of constricted tubular visual field].

    Science.gov (United States)

    Dogaru, Oana-Mihaela; Rusu, Monica; Hâncu, Dacia; Horvath, Kárin

    2013-01-01

    In the paper below we present the clinical case of a 48 year old female with various symptoms associated with functional visual disturbance -constricted tubular visual fields, wich lasts from 6 years; the extensive clinical and paraclinical ophthalmological investigations ruled out the presence of an organic disorder. In the present, we suspect a diagnosis of hysteria, still uncertain, wich represented over time a big challenge in psychology and ophthalmology. The mechanisms and reasons for hysteria are still not clear and it could represent a fascinating research theme. The tunnel, spiral or star-shaped visual fields are specific findings in hysteria for patients who present visual disturbance. The question of whether or not a patient with hysterical visual impairment can or cannot "see" is still unresolved.

  20. Tubular adenoid cystic carcinoma of palate: A rare case report

    Directory of Open Access Journals (Sweden)

    Deepanshu Garg

    2015-01-01

    Full Text Available Adenoid cystic carcinoma (ACC is a rare malignant tumor that affects the major and minor salivary glands, the lacrimal glands, the ceruminous glands and occasionally the excretory glands of the female genital tract. 30-40% of these carcinomas occur in the head and neck region. Approximately 50-70% of the cases have been reported in the minor salivary glands. The most common location is the palate, generally in the area of the greater palatine foramen. ACC is generally characterized by a slow growth rate, and it is often present for several years before the patient seeks treatment. Here we present a case of 42-year-old female who came to the department for the complaint of a swelling over the right side of palate since 2-3 months which was diagnosed as a benign tumor initially, but was confirmed as tubular ACC histologically.

  1. Primordial membranes

    DEFF Research Database (Denmark)

    Hanczyc, Martin M; Monnard, Pierre-Alain

    2017-01-01

    Cellular membranes, which are self-assembled bilayer structures mainly composed of lipids, proteins and conjugated polysaccharides, are the defining feature of cell physiology. It is likely that the complexity of contemporary cells was preceded by simpler chemical systems or protocells during...... the various evolutionary stages that led from inanimate to living matter. It is also likely that primitive membranes played a similar role in protocell 'physiology'. The composition of such ancestral membranes has been proposed as mixtures of single hydrocarbon chain amphiphiles, which are simpler versions...

  2. Design of a Compact and Versatile Bench Scale Tubular Reactor

    Directory of Open Access Journals (Sweden)

    R. Prasad

    2009-06-01

    Full Text Available A compact and versatile laboratory tubular reactor has been designed and fabricated keeping in view of reducing capital cost and minimising energy consumption for gas/vapor-phase heterogeneous catalytic reactions. The reactor is consisted of two coaxial corning glass tubes with a helical coil of glass tube in between the coaxial tubes serving as vaporiser and pre-heater, the catalyst bed is in the inner tube. A schematic diagram of the reactor with detailed dimensions and working principles are described. The attractive feature of the reactor is that the vaporiser, pre-heater and fixed bed reactor are merged in a single compact unit. Thus, the unit minimises separate vaporiser and pre-heater, also avoids separate furnaces used for them and eliminate auxiliary instrumentation such as temperature controller etc. To demonstrate the system operation and illustrate the key features, catalyst screening data and the efficient collection of complete, and accurate intrinsic kinetic data are provided for oxidation of CO over copper chromite catalyst. CO oxidation is an important reaction for auto-exhaust pollution control. The suitability of the versatile nature of the reactor has been ascertained for catalytic reactions where either volatile or vaporizable feeds can be introduced to the reaction zone, e.g. oxidation of iso-octane, reduction of nitric oxide, dehydrogenation of methanol, ethanol and iso-propanol, hydrogenation of nitrobenzene to aniline, etc. Copyright (c 2009 by BCREC. All Rights reserved.[Received: 10 February 2009, Accepted: 9 May 2009][How to Cite: R. Prasad, G. Rattan. (2009. Design of a Compact and Versatile Bench Scale Tubular Reactor. Bulletin of Chemical Reaction Engineering and Catalysis, 4(1: 5-9.  doi:10.9767/bcrec.4.1.1250.5-9][How to Link/ DOI: http://dx.doi.org/10.9767/bcrec.4.1.1250.5-9

  3. Tubular Scaffold with Shape Recovery Effect for Cell Guide Applications

    Directory of Open Access Journals (Sweden)

    Kazi M. Zakir Hossain

    2015-07-01

    Full Text Available Tubular scaffolds with aligned polylactic acid (PLA fibres were fabricated for cell guide applications by immersing rolled PLA fibre mats into a polyvinyl acetate (PVAc solution to bind the mats. The PVAc solution was also mixed with up to 30 wt % β-tricalcium phosphate (β-TCP content. Cross-sectional images of the scaffold materials obtained via scanning electron microscopy (SEM revealed the aligned fibre morphology along with a significant number of voids in between the bundles of fibres. The addition of β-TCP into the scaffolds played an important role in increasing the void content from 17.1% to 25.3% for the 30 wt % β-TCP loading, which was measured via micro-CT (µCT analysis. Furthermore, µCT analyses revealed the distribution of aggregated β-TCP particles in between the various PLA fibre layers of the scaffold. The compressive modulus properties of the scaffolds increased from 66 MPa to 83 MPa and the compressive strength properties decreased from 67 MPa to 41 MPa for the 30 wt % β-TCP content scaffold. The scaffolds produced were observed to change into a soft and flexible form which demonstrated shape recovery properties after immersion in phosphate buffered saline (PBS media at 37 °C for 24 h. The cytocompatibility studies (using MG-63 human osteosarcoma cell line revealed preferential cell proliferation along the longitudinal direction of the fibres as compared to the control tissue culture plastic. The manufacturing process highlighted above reveals a simple process for inducing controlled cell alignment and varying porosity features within tubular scaffolds for potential tissue engineering applications.

  4. Optimal Surgery for Mid-Transverse Colon Cancer: Laparoscopic Extended Right Hemicolectomy Versus Laparoscopic Transverse Colectomy.

    Science.gov (United States)

    Matsuda, Takeru; Sumi, Yasuo; Yamashita, Kimihiro; Hasegawa, Hiroshi; Yamamoto, Masashi; Matsuda, Yoshiko; Kanaji, Shingo; Oshikiri, Taro; Nakamura, Tetsu; Suzuki, Satoshi; Kakeji, Yoshihiro

    2018-04-02

    Although the feasibility and safety of laparoscopic surgery for transverse colon cancer have been shown by the recent studies, the optimal laparoscopic approach for mid-transverse colon cancer is controversial. We retrospectively analyzed the data of patients with the mid-transverse colon cancer at our institutions between January 2007 and April 2017. Thirty-eight and 34 patients who received extended right hemicolectomy and transverse colectomy, respectively, were enrolled. There were no significant differences in operating time, blood loss, and hospital stay between the two groups. Postoperative complications developed in 10 of 34 patients (29.4%; wound infection: 2 cases, anastomotic leakage: 2 cases, bowel obstruction: 1 case, incisional hernia: 2 cases, others: 3 cases) for the transverse colectomy group and in 4 of 38 patients (10.5%; wound infection: 1 case, anastomotic leakage: 0 case, bowel obstruction: 2 cases, incisional hernia: 0 case, others: 1 case) for the extended right hemicolectomy group (P = 0.014). Although the median number of harvested #221 and #222 LNs was similar between the two groups (6 vs. 8, P = 0.710, and 3 vs. 2, P = 0.256, respectively), that of #223 was significantly larger in extended right hemicolectomy than in transverse colectomy (3 vs. 1, P = 0.038). The 5-year disease-free and overall survival rates were 92.4 and 90.3% for the extended right hemicolectomy group, and 95.7 and 79.6% for the transverse colectomy group (P = 0.593 and P = 0.638, respectively). Laparoscopic extended right hemicolectomy and laparoscopic transverse colectomy offer similar oncological outcomes for mid-transverse colon cancer. Laparoscopic extended right hemicolectomy might be associated with fewer postoperative complications.

  5. Parametric Transverse Patterns in Broad Aperture Lasers

    DEFF Research Database (Denmark)

    Grigorieva, E.V.; Kashchenko, S.A.; Mosekilde, Erik

    1998-01-01

    Parametrically generated optical patterns are investigated for finite and large-scale transverse aperture lasers. Standing and rotating patterns as well as periodic and chaotic pattern alternations are described in the framework of the amplitude equation formalism. Sensitive dependence...... on the geometrical size of the system is demonstrated even in the case of large-scale systems....

  6. Longitudinal Evaluation of Foetal Transverse Lie using ...

    African Journals Online (AJOL)

    Erah

    , lower segment fibroids in 2.7%, and ectopic kidney in 0.7%. In conclusion, transverse lie detected early in pregnancy is transient, and majority would convert to a longitudinal lie at term. Potential predisposing factors highlighted above ...

  7. Rapid communication: Transverse spin with coupled plasmons

    Indian Academy of Sciences (India)

    In contrast to some of the earlier studies, calculations are performed retaining the full lossy character of the metal. In the limit of vanishing losses, we present analytical results for the extraordinary spin for both the coupled modes. The results can have direct implications for enhancing the elusive transverse spin exploiting the ...

  8. Transverse momentum distributions of identified particles produced ...

    Indian Academy of Sciences (India)

    ... sources which can be regarded as partons or quarks in the interacting system. The particle is contributed by each source with gluons which have transverse momentum distributions in an exponential form. The modelling results are compared and found to be in agreement with the experimental data at high energies.

  9. Sex Education as a Transversal Subject

    Science.gov (United States)

    Rabelo, Amanda Oliveira; Pereira, Graziela Raupp; Reis, Maria Amélia; Ferreira, António G.

    2015-01-01

    Currently, sex education is in many countries a transversal subject, in which the school becomes a privileged place for the implementation of policies that aim at promoting "public health." Its design as a cross-cutting subject envisages fostering the dissemination of these subjects in all pedagogical and curricular fields; however, we…

  10. Transverse spin and momentum correlations in quantum ...

    Indian Academy of Sciences (India)

    (SSAs) in hard scattering processes when transverse momentum scales are on the order of quarks in hadrons, ... are of particular interest as they emerge from the colour gauge invariant definition of the quark-gluon-quark ..... For n ≥ 3, there are enough powers of l+ to eliminate this divergence. f(p2) is a covariant Gaussian ...

  11. TRANSVERSE COLON POUCH: AN ALTERNATIVE TO ...

    African Journals Online (AJOL)

    Objective Urinary diversion after pelvic irradiation is challenging. The use of irradiated bowel is mostly complicated and unsuccessful. Therefore, the use of an exclusively non-irradiated bowel segment, such as the transverse colon, is a good alternative in such situation. Patients and Methods Twenty-nine female patients ...

  12. Transversals in non-discrete groups

    Indian Academy of Sciences (India)

    Home; Journals; Proceedings – Mathematical Sciences; Volume 115; Issue 4 ... Given any right quasigroup with a Tychonoff topology , it is proved that there exists a Hausdorff topological group in which can be embedded algebraically and topologically as a right transversal of a subgroup (not necessarily closeed).

  13. Rapid communication: Transverse spin with coupled plasmons

    Indian Academy of Sciences (India)

    Samyobrata Mukherjee

    2017-07-25

    Jul 25, 2017 ... spline interpolation from the data of Johnson and Christy. [31]. But first, we have to deal with normalization in order to make our comparisons of the transverse spin for different wavelengths and metal film thicknesses d meaningful. We normalize the power flow into the sys- tem at x = 0 to unity. ∫ ∞. −∞.

  14. Transverse Ising model with multi-impurity

    International Nuclear Information System (INIS)

    Huang, Xuchu; Yang, Zhihua

    2015-01-01

    We study the transverse Ising spin model with spin-1 impurities under the exact solution. We develop a universal method to deal with the multi-impurity problem by introducing a displacement quantity in the wave function and get a recursive formula to simplify the calculation of the partition function. This allows us to rigorously determine the impurity effects for a specific distribution of impurity in the thermodynamic limit. The low temperature behaviors are governed by the interplay between host and impurity excitations, and the quantum critical fluctuations around the critical point of the transverse Ising model are tuned by the transverse field and the concentration of impurity. However the impurity effects are limited, which depends on the host–impurity exchange interaction and the coupling strength of impurities. - Highlights: • A universal method is proposed to exactly resolve the transverse Ising model with many impurities. • The phase diagram of the ground state is obtained for different impurity concentrations. • The thermodynamic properties can be determined rigorously by a recursive formula in the thermodynamic limit

  15. Transversals in non-discrete groups

    Indian Academy of Sciences (India)

    1963). [7] Lal R, Transversals in groups, J. Alg. 181 (1996) 70–81. [8] Lal R and Shukla R P, Perfectly stable subgroups of finite groups, Comm. Alg. 24(2). (1996) 643–657. [9] Lal R and Shukla R P, A characterization of Tarski monsters, ...

  16. Rapid communication: Transverse spin with coupled plasmons

    Indian Academy of Sciences (India)

    Samyobrata Mukherjee

    2017-07-25

    Jul 25, 2017 ... Rapid communication: Transverse spin with coupled plasmons. SAMYOBRATA MUKHERJEE1, A V GOPAL2 and S DUTTA GUPTA1,∗. 1School of Physics, University of Hyderabad, Gachibowli, Hyderabad 500 046, India. 2Department of Condensed Matter Physics and Materials Science, Tata Institute of ...

  17. EFFECT OF CHANNEL BENDS ON TRANSVERSE MIXING

    African Journals Online (AJOL)

    user

    2017-06-05

    Jun 5, 2017 ... dy, where d is the flow depth, was found to vary laterally in all cross-sections. As the spiral motion due to the second bend develops it displaces the residual spiral motion from the first bend towards the outer bend causing it to decay completely around the middle of this bend. Transverse Tracer Distribution.

  18. Fractional excretion of magnesium (FEMg), a marker for tubular dysfunction in children with clinically recovered ischemic acute tubular necrosis.

    Science.gov (United States)

    Gheissari, Alaleh; Andalib, Alireza; Labibzadeh, Narges; Modarresi, Mohammadreza; Azhir, Afshin; Merrikhi, Alireza

    2011-05-01

    Among the different etiologies of acute renal failure (ARF), acute tubular necrosis (ATN) is one of the most common causes. There is no consensus on the duration of follow-up needed among these patients and also on choosing a reliable screening test to recognize early signs of chronic kidney injury that may ensue. The aim of this study was to evaluate the clinical and biochemical findings in children with a history of clinically recovered ischemic ATN, to detect the patients who may be at risk of ensuing chronic kidney disease. A cross-sectional study was carried out on 20 children between six months and 10 years of age, admitted at St. Al Zahra Hospital and Amin Children's Hospital, Isfahan, Iran, with a past history of ischemic ATN. Eighteen patients were evaluated between 12 and 24 months, and two patients were evaluated at 30 months. The second sample of urine while still fasting was used for assessing urinary sodium, creatinine and magnesium. The mean ages for study and control groups were 3.4 ± 1.3 years and 4.5 ± 1.1 years, respectively. Glomerular filtration rate, urinary magnesium, fractional excretion of magnesium (FEMg), urinary sodium and fractional excretion of sodium (FENa) were significantly higher in the study group compared to those in the control group. No significant differences were demonstrated in systolic and diastolic blood pressures between the two groups. Since FEMg can reflect tubular function for both the ability of tubules for reabsorption of the filtered magnesium and for retaining the intracellular magnesium, FEMg can be used as a marker to detect early stages of chronic renal injury. However, further studies with larger number of cases are needed to evaluate the sensitivity of this test.

  19. Fractional excretion of magnesium (FEMg, a marker for tubular dysfunction in children with clinically recovered ischemic acute tubular necrosis

    Directory of Open Access Journals (Sweden)

    Alaleh Gheissari

    2011-01-01

    Full Text Available Among the different etiologies of acute renal failure (ARF, acute tubular necrosis (ATN is one of the most common causes. There is no consensus on the duration of follow-up needed among these patients and also on choosing a reliable screening test to recognize early signs of chronic kidney injury that may ensue. The aim of this study was to evaluate the clinical and biochemical findings in children with a history of clinically recovered ischemic ATN, to detect the patients who may be at risk of ensuing chronic kidney disease. A cross-sectional study was carried out on 20 children between six months and 10 years of age, admitted at St. Al Zahra Hospital and Amin Children′s Hospital, Isfahan, Iran, with a past history of ischemic ATN. Eighteen patients were evaluated between 12 and 24 months, and two patients were evaluated at 30 months. The second sample of urine while still fasting was used for assessing urinary sodium, creatinine and magnesium. The mean ages for study and control groups were 3.4 ± 1.3 years and 4.5 ± 1.1 years, respectively. Glomerular filtration rate, urinary magnesium, fractional excretion of magnesium (FEMg, urinary sodium and fractional excretion of sodium (FENa were significantly higher in the study group compared to those in the control group. No significant differences were demonstrated in systolic and diastolic blood pressures between the two groups. Since FEMg can reflect tubular function for both the ability of tubules for reabsorption of the filtered magnesium and for retaining the intracellular magnesium, FEMg can be used as a marker to detect early stages of chronic renal injury. However, further studies with larger number of cases are needed to evaluate the sensitivity of this test.

  20. Mapping of moveout in tilted transversely isotropic media

    KAUST Repository

    Stovas, A.

    2013-09-09

    The computation of traveltimes in a transverse isotropic medium with a tilted symmetry axis tilted transversely isotropic is very important both for modelling and inversion. We develop a simple analytical procedure to map the traveltime function from a transverse isotropic medium with a vertical symmetry axis (vertical transversely isotropic) to a tilted transversely isotropic medium by applying point-by-point mapping of the traveltime function. This approach can be used for kinematic modelling and inversion in layered tilted transversely isotropic media. © 2013 European Association of Geoscientists & Engineers.

  1. Distal Renal Tubular Acidosis Screening by Urinary Acidification Testing in Mexican Children.

    Science.gov (United States)

    Guerra-Hernández, Norma E; Ordaz-López, Karen V; Escobar-Pérez, Laura; Gómez-Tenorio, Circe; García-Nieto, Víctor M

    2015-01-01

    Primary distal renal tubular acidosis is a clinical disorder characterized by hyperchloremic metabolic acidosis, hypercalciuria, hypocitraturia, urinary acidification impairment, hypokalemia, metabolic bone disease, and nephrocalcinosis. Urinary acidification ability may be evaluated by an acidification test or maximum urinary pCO2 assessment with alkaline urine. The maximum urinary pCO2 test using acetazolamide and sodium bicarbonate is an easy test to confirm the lack of urine acidification in distal renal tubular acidosis in children. To determine the urinary acidification ability using the maximum urinary pCO2 assessment in a group of children with a distal renal tubular acidosis diagnosis. Thirty children were evaluated (13 males and 17 females); 23 children had been diagnosed with distal renal tubular acidosis by other physicians and were under alkali treatment with potassium and sodium citrates (21) and bicarbonate (2), and five children were not under alkali treatment. Two children had been diagnosed with primary distal renal tubular acidosis by our medical group. The maximum urinary pCO2 was determined by the oral intake of acetazolamide and sodium bicarbonate. Two cases with primary distal renal tubular acidosis were found, and they had a history of dehydration episodes during infancy and showed hyperchloremic metabolic acidosis with hypokalemia. They also exhibited urine acidification impairment with furosemide and reduced urinary pCO2 (renal tubular acidosis with hyperaminoaciduria was identified. Twenty-eight children displayed normal urinary acidification and did not show signs of distal renal tubular acidosis. The urinary acidification test with furosemide and urinary pCO2 assessment are reliable tests to identify the renal excretion of hydrogen ions (H+) and allow confirmation of the lack of urine acidification in distal renal tubular acidosis.

  2. Kidney specific protein-positive cells derived from embryonic stem cells reproduce tubular structures in vitro and differentiate into renal tubular cells.

    Science.gov (United States)

    Morizane, Ryuji; Monkawa, Toshiaki; Fujii, Shizuka; Yamaguchi, Shintaro; Homma, Koichiro; Matsuzaki, Yumi; Okano, Hideyuki; Itoh, Hiroshi

    2014-01-01

    Embryonic stem cells and induced pluripotent stem cells have the ability to differentiate into various organs and tissues, and are regarded as new tools for the elucidation of disease mechanisms as well as sources for regenerative therapies. However, a method of inducing organ-specific cells from pluripotent stem cells is urgently needed. Although many scientists have been developing methods to induce various organ-specific cells from pluripotent stem cells, renal lineage cells have yet to be induced in vitro because of the complexity of kidney structures and the diversity of kidney-component cells. Here, we describe a method of inducing renal tubular cells from mouse embryonic stem cells via the cell purification of kidney specific protein (KSP)-positive cells using an anti-KSP antibody. The global gene expression profiles of KSP-positive cells derived from ES cells exhibited characteristics similar to those of cells in the developing kidney, and KSP-positive cells had the capacity to form tubular structures resembling renal tubular cells when grown in a 3D culture in Matrigel. Moreover, our results indicated that KSP-positive cells acquired the characteristics of each segment of renal tubular cells through tubular formation when stimulated with Wnt4. This method is an important step toward kidney disease research using pluripotent stem cells, and the development of kidney regeneration therapies.

  3. Membranes obtained from alumina from separation water/oil

    International Nuclear Information System (INIS)

    Rosas Neto, M.I.; Lira, H.L; Guimaraes, I.O; Franca, K.B.

    2016-01-01

    This study aims to evaluate by flow test emulsion water/oil a membrane obtained from a crude residue of the alumina industry and see if this membrane is able to filter this emulsion within the limits specified by CONAMA. In this work, tubular membranes composed of the alumina and the residue bentonite clay were produced by extrusion and were sintered at 900, 1000 and 1100 ° C. tangential flow tests were conducted with deionized water and subsequently with an emulsion of water / oil, all done with a pressure of 1.5 bar. The results showed that membranes produced from the crude residue the alumina industry were quite efficient the emulsion's oil removal, reducing the concentration of about 100 ppm in the feed, to below 5ppm and flow rates of around 30L/h.m 2 . (author)

  4. Vacuum seeding and secondary growth route to sodalite membrane

    International Nuclear Information System (INIS)

    Lee, Sung-Reol; Son, You-Hwan; Julbe, Anne; Choy, Jin-Ho

    2006-01-01

    Sodalite membrane has been successfully fabricated on tubular porous α-Al 2 O 3 supports by secondary growth method with vacuum seeding. In the seeding process, the colloidal seeding particles were agglutinated not only onto the surface of alumina support but also within the pores by vacuum sucking method. To obtain defect-free sodalite membrane, the sodalite crystals were grown directly on the alumina support in a mixture solution containing alumina and silica species under the hydrothermal reaction condition. The as-synthesized sodalite membranes were characterized by X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM). The thickness and the quality of sodalite membrane could be controlled by the hydrothermal reaction time (12∼24 h) and temperature (100∼150 deg. C) under the mother solution of 5Na 2 O : 2SiO 2 : Al 2 O 3 : 1000H 2 O

  5. Congenital myopathy with tubular aggregates: report on two siblings from India.

    Science.gov (United States)

    Narayanappa, Gayathri; Nalini, Atchayaram; Thaha, Fazil

    2009-07-01

    The clinical features and morphological findings in 2 Indian siblings with tubular aggregates are described. The siblings aged 14 and 9 years, respectively, born of consanguineous marriage presented with early onset gradually progressive lower limb proximal muscle weakness associated with seizures and mental subnormality. Muscle biopsy in both revealed characteristic tubular aggregates in type II fibers, which were confirmed electron microscopically. To the best of our knowledge, association of seizures and mental subnormality in familial tubular aggregates has not been described. Muscle biopsy helped in establishing the diagnosis of this rare familial disorder.

  6. Undulating tubular liposomes through incorporation of a synthetic skin ceramide into phospholipid bilayers.

    Science.gov (United States)

    Xu, Peng; Tan, Grace; Zhou, Jia; He, Jibao; Lawson, Louise B; McPherson, Gary L; John, Vijay T

    2009-09-15

    Nonspherical liposomes were prepared by doping L-alpha-phosphatidylcholine (PC) with ceramide VI (a skin lipid). Cryo-transmission electron microscopy shows the liposome shape changing from spherical to an undulating tubular morphology, when the amount of ceramide VI is increased. The formation of tubular liposomes is energetically favorable and is attributed to the association of ceramide VI with PC creating regions of lower curvature. Since ceramides are the major component of skin lipids in the stratum corneum, tubular liposomes containing ceramide may potentially serve as self-enhanced nanocarriers for transdermal delivery.

  7. Micro-drilling of polymer tubular ultramicroelectrode arrays for electrochemical sensors

    DEFF Research Database (Denmark)

    Kafka, Jan Robert; Skaarup, Steen; Geschke, Oliver

    2013-01-01

    We present a reproducible fast prototyping procedure based on micro-drilling to produce homogeneous tubular ultramicroelectrode arrays made from poly(3,4-ethylenedioxythiophene) (PEDOT), a conductive polymer. Arrays of Ø 100 μm tubular electrodes each having a height of 0.37 ± 0.06 μm were...... were in agreement with results from finite element modelling of the system. The tubular PEDOT ultramicroelectrode arrays were modified by prussian blue to enable the detection of hydrogen peroxide. A linear sensor response was demonstrated for hydrogen peroxide concentrations from 0.1 mM to 1 mM....

  8. High Transverse Energy Proton - Nuclear Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Rice, James Allen [Rice Univ., Houston, TX (United States)

    1983-06-01

    A study of high transverse energy events resulting from 400 GeV protons scattering from targets of hydrogen, carbon, aluminum, copper, tin, and lead has been performed with the E609 apparatus at Fermilab. Wire chambers and a highly segmented calorimeter detect secondary particles. The use of efficient jet collecting triggers and of a beam jet calorimeter have been originally applied to nuclear target studies in this thesis. $A^{\\alpha}$ scaling with hydrogen deviations is observed for $E_T$ and planarity. The data provide evidence that $A^{\\alpha}$ scaling results from multiple scattering.Evidence for hadron jets is seen with a large solid angle calorimeter for all the targets when triggers requiring two high $E_T$ single particles are employed. Jet cross-sections for nuclei are approximately determined herein. Jet event angular distributions possibly indicate that low and high transverse energy particles in jets from nuclei may result, in part, from different types of interactions.

  9. Transversals of Complex Polynomial Vector Fields

    DEFF Research Database (Denmark)

    Dias, Kealey

    Vector fields in the complex plane are defined by assigning the vector determined by the value P(z) to each point z in the complex plane, where P is a polynomial of one complex variable. We consider special families of so-called rotated vector fields that are determined by a polynomial multiplied...... by rotational constants. Transversals are a certain class of curves for such a family of vector fields that represent the bifurcation states for this family of vector fields. More specifically, transversals are curves that coincide with a homoclinic separatrix for some rotation of the vector field. Given...... a concrete polynomial, it seems to take quite a bit of work to prove that it is generic, i.e. structurally stable. This has been done for a special class of degree d polynomial vector fields having simple equilibrium points at the d roots of unity, d odd. In proving that such vector fields are generic...

  10. Borel resummation of transverse momentum distributions

    International Nuclear Information System (INIS)

    Bonvini, Marco; Forte, Stefano; Ridolfi, Giovanni

    2009-01-01

    We present a new prescription for the resummation of contributions due to soft gluon emission to the transverse momentum distribution of processes such as Drell-Yan production in hadronic collisions. We show that familiar difficulties in obtaining resummed results as a function of transverse momentum starting from impact-parameter space resummation are related to the divergence of the perturbative expansion of the momentum-space result. We construct a resummed expression by Borel resummation of this divergent series, removing the divergence in the Borel inversion through the inclusion of a suitable higher twist term. The ensuing resummation prescription is free of numerical instabilities, is stable upon the inclusion of subleading terms, and the original divergent perturbative series is asymptotic to it. We compare our results to those obtained using alternative prescriptions, and discuss the ambiguities related to the resummation procedure

  11. Transverse Instability of a Rectangular Bunch

    CERN Document Server

    Balbekov, Valeri

    2005-01-01

    Some results of theoretical investigations of transverse dipole instability of a rectangular bunch are reported in this paper. Such a form is characteristic of the bunch in a rectangular potential wall which is created by a barrier-shaped acceleration field. Similar regime is a major one for accumulating and cooling of antiproton beams in the Fermilab Recycler Ring. In this case, the known theory of transverse instability of a bunched beam is inapplicable directly both because of "unusual" form of phase trajectories and strong dependence of synchrotron frequency on energy. A series of equations, adequately describing the instability is derived in the paper. Exact analytical solution is obtained for space charge dominated impedance, and some approximate methods are proposed for arbitrary impedance. The theory is applied to the Fermilab Recycler Ring including a numerical simulation.

  12. Spectral Velocity Estimation in the Transverse Direction

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt

    2013-01-01

    A method for estimating the velocity spectrum for a fully transverse flow at a beam-to-flow angle of 90is described. The approach is based on the transverse oscillation (TO) method, where an oscillation across the ultrasound beam is made during receive processing. A fourth-order estimator based...... on the correlation of the received signal is derived. A Fourier transform of the correlation signal yields the velocity spectrum. Performing the estimation for short data segments gives the velocity spectrum as a function of time as for ordinary spectrograms, and it also works for a beam-to-flow angle of 90...... estimation scheme can reliably find the spectrum at 90, where a traditional estimator yields zero velocity. Measurements have been conducted with the SARUS experimental scanner and a BK 8820e convex array transducer (BK Medical, Herlev, Denmark). A CompuFlow 1000 (Shelley Automation, Inc, Toronto, Canada...

  13. MEASUREMENT OF TRANSVERSE ECHOES IN RHIC

    International Nuclear Information System (INIS)

    FISCHER, W.; SATOGATA, T.; TOMAS, R.

    2005-01-01

    Beam echoes are a very sensitive method to measure diffusion, and longitudinal echo measurements were performed in a number of machines. In RHIC, for the first time, a transverse beam echo was observed after applying a dipole kick followed by a quadrupole .kick. After application of the dipole kick, the dipole moment decohered completely due to lattice nonlinearities. When a quadrupole kick is applied at time τ after the dipole kick, the beam re-cohered at time 2τ thus showing an echo response. We describe the experimental setup and measurement results. In the measurements the dipole and quadrupole kick amplitudes, amplitude dependent tune shift, and the time between dipole and quadrupole kick were varied. In addition, measurements were taken with gold bunches of different intensities. These should exhibit different transverse diffusion rates due to intra-beam scattering

  14. Antiphospholipid antibody syndrome presenting as transverse myelitis

    Directory of Open Access Journals (Sweden)

    Javvid M Dandroo

    2015-01-01

    Full Text Available The antiphospholipid syndrome (APS is characterized by arterial and/or venous thrombosis and pregnancy morbidity in the presence of anticardiolipin antibodies and/or lupus anticoagulant. APS can occur either as a primary disorder or secondary to a connective tissue disease, most frequently systemic lupus erythematosus. Central nervous system involvement is one of the most prominent clinical manifestations of APS, and includes arterial and venous thrombotic events, psychiatric features, and a variety of other nonthrombotic neurological syndromes. Although the mechanism of neurological involvement in patients with APS is thought to be thrombotic in origin and endothelial dysfunction associated with antiphospholipid antibodies. APS presenting as acute transverse myelitis is very rarely seen with a prevalence rate of 1%. We are describing a foreigner female presenting as acute transverse myelitis which on evaluation proved to be APS induced. So far, very few cases have been reported in literature with APS as etiology.

  15. Nonlinear theory of transverse beam echoes

    Energy Technology Data Exchange (ETDEWEB)

    Sen, Tanaji; Li, Yuan Shen

    2017-10-04

    Transverse beam echoes can be excited with a single dipole kick followed by a single quadrupole kick. They have been used to measure diffusion in hadron beams and have other diagnostic capabilities. Here we develop theories of the transverse echo nonlinear in both the dipole and quadrupole kick strengths. The theories predict the maximum echo amplitudes and the optimum strength parameters. We find that the echo amplitude increases with smaller beam emittance and the asymptotic echo amplitude can exceed half the initial dipole kick amplitude. We show that multiple echoes can be observed provided the dipole kick is large enough. The spectrum of the echo pulse can be used to determine the nonlinear detuning parameter with small amplitude dipole kicks. Simulations are performed to check the theoretical predictions. In the useful ranges of dipole and quadrupole strengths, they are shown to be in reasonable agreement.

  16. Transverse Instabilities in the Fermilab Recycler

    Energy Technology Data Exchange (ETDEWEB)

    Prost, L.R.; Burov, A.; Shemyakin, A.; Bhat, C.M.; Crisp, J.; Eddy, N.; /Fermilab

    2011-07-01

    Transverse instabilities of the antiproton beam have been observed in the Recycler ring soon after its commissioning. After installation of transverse dampers, the threshold for the instability limit increased significantly but the instability is still found to limit the brightness of the antiprotons extracted from the Recycler for Tevatron shots. In this paper, we describe observations of the instabilities during the extraction process as well as during dedicated studies. The measured instability threshold phase density agrees with the prediction of the rigid beam model within a factor of 2. Also, we conclude that the instability threshold can be significantly lowered for a bunch contained in a narrow and shallow potential well due to effective exclusion of the longitudinal tails from Landau damping.

  17. Tubular overexpression of Gremlin in transgenic mice aggravates renal damage in diabetic nephropathy.

    Science.gov (United States)

    Marchant, Vanessa; Droguett, Alejandra; Valderrama, Graciela; Burgos, M Eugenia; Carpio, Daniel; Kerr, Bredford; Ruiz-Ortega, Marta; Egido, Jesús; Mezzano, Sergio

    2015-09-15

    Diabetic nephropathy (DN) is currently a leading cause of end-stage renal failure worldwide. Gremlin was identified as a gene differentially expressed in mesangial cells exposed to high glucose and in experimental diabetic kidneys. We have described that Gremlin is highly expressed in biopsies from patients with diabetic nephropathy, predominantly in areas of tubulointerstitial fibrosis. In streptozotocin (STZ)-induced experimental diabetes, Gremlin deletion using Grem1 heterozygous knockout mice or by gene silencing, ameliorates renal damage. To study the in vivo role of Gremlin in renal damage, we developed a diabetic model induced by STZ in transgenic (TG) mice expressing human Gremlin in proximal tubular epithelial cells. The albuminuria/creatinuria ratio, determined at week 20 after treatment, was significantly increased in diabetic mice but with no significant differences between transgenic (TG/STZ) and wild-type mice (WT/STZ). To assess the level of renal damage, kidney tissue was analyzed by light microscopy (periodic acid-Schiff and Masson staining), electron microscopy, and quantitative PCR. TG/STZ mice had significantly greater thickening of the glomerular basement membrane, increased mesangial matrix, and podocytopenia vs. WT/STZ. At the tubulointerstitial level, TG/STZ showed increased cell infiltration and mild interstitial fibrosis. In addition, we observed a decreased expression of podocin and overexpression of monocyte chemoattractant protein-1 and fibrotic-related markers, including transforming growth factor-β1, Col1a1, and α-smooth muscle actin. Together, these results show that TG mice overexpressing Gremlin in renal tubules develop greater glomerular and tubulointerstitial injury in response to diabetic-mediated damage and support the involvement of Gremlin in diabetic nephropathy. Copyright © 2015 the American Physiological Society.

  18. The LHC Transverse Damper (ADT) Performance Specification

    CERN Document Server

    Boussard, Daniel; Linnecar, Trevor Paul R; CERN. Geneva. SPS and LEP Division

    1997-01-01

    The appended document specifies the performance of the transverse damper (ADT) for the LHC. As Annex 1 of the Addendum No.1 to the Protocol of April 18, 1997; it forms part of the 1992 co-operation agreement between CERN and JINR (Dubna, Russia) concerning its participation in the LHC project. The current text is a reprint of the original version. Changes that have been agreed upon are inserted as footnotes.

  19. Sasakian manifolds with purely transversal Bach tensor

    Science.gov (United States)

    Ghosh, Amalendu; Sharma, Ramesh

    2017-10-01

    We show that a (2n + 1)-dimensional Sasakian manifold (M, g) with a purely transversal Bach tensor has constant scalar curvature ≥2 n (2 n +1 ) , equality holding if and only if (M, g) is Einstein. For dimension 3, M is locally isometric to the unit sphere S3. For dimension 5, if in addition (M, g) is complete, then it has positive Ricci curvature and is compact with finite fundamental group π1(M).

  20. Resolution of hydrodynamical equations for transverse expansions

    International Nuclear Information System (INIS)

    Hama, Y.; Pottag, F.W.

    1984-01-01

    The three-dimensional hydrodynamical expansion is treated with a method similar to that of Milekhin, but more explicit. Although in the final stage one have to appeal to numerical calculation, the partial differential equations governing the transverse expansions are treated without transforming them into ordinary equations with an introduction of averaged quantities. It is only concerned with the formalism and the numerical results will be given in the next paper. (Author) [pt

  1. Transversally Lipschitz Harmonic Functions are Lipschitz

    OpenAIRE

    Ravisankar, Sivaguru

    2012-01-01

    Let \\Omega\\subset\\mathbb{R}^n be a bounded domain with C^\\infty boundary. We show that a harmonic function in \\Omega that is Lipschitz along a family of curves transversal to b\\Omega is Lipschitz in \\Omega. The space of Lipschitz functions we consider is defined using the notion of a majorant which is a certain generalization of the power functions t^\\alpha, 0

  2. Nuclear transverse sectional brain function imager

    International Nuclear Information System (INIS)

    Stoddart, H.F.

    1982-01-01

    A transverse radionuclide scan field imaging apparatus comprises a plurality of highly focused closely laterally adjacent collimators arranged inwardly focused in an array that surrounds a scan field of interest. Each collimator is moveable relative to its adjacent collimator. Means are provided for imparting travel to the collimators such that the focal point of each uniformly samples at least one half of the scan field

  3. Transverse electron beam diagnostics at REGAE

    International Nuclear Information System (INIS)

    Bayesteh, Shima

    2014-12-01

    The use of high-intensity electron and X-ray pulsed sources allows for the direct observation of atomic motions as they occur. While the production of such high coherent, brilliant, short X-ray pulses requires large-scale and costly accelerator facilities, it is feasible to employ a high-intensity source of electrons by exploiting a more compact design. The Relativistic Electron Gun for Atomic Exploration (REGAE) facility is a small linear accelerator at DESY, Hamburg, equipped with a photocathode radio frequency (RF) gun that produces relativistic ultra-short (<100 fs), low charge (<1 pC) electron bunches of high coherence. By means of time-resolved diffraction experiments, such an electron source can probe ultrafast laser-induced atomic structural changes that occur with a temporal resolution of ∝100 fs. A comprehensive characterization of the electron beam, for every pulse, is of fundamental importance to study the atomic motions with the desired resolution and quality. This thesis reports on the transversal diagnostics of the electron beam with an emphasis on a scintillator-based beam profile monitor. The diagnostics is capable of evaluating the beam parameters such as charge, energy, energy spread and transverse profile, at very low charges and on a shot-to-shot basis. A full characterization of the scintillator's emission, the optical setup and the detector (camera) of the profile monitor is presented, from which an absolute charge calibration of the system is derived. The profile monitor is specially developed to accommodate more applications, such as dark current suppression, overlapping the electron probe and the laser pump within 1 ns accuracy, as well as charge and transverse emittance measurements. For the determination of the transverse emittance two techniques were applied. The first one introduces a new method that exploits a diffraction pattern to measure the emittance, while the second one is based on a version of the Pepper-pot technique. A

  4. The Association of Albuminuria With Tubular Reabsorption of Uric Acid : Results From a General Population Cohort

    NARCIS (Netherlands)

    Scheven, Lieneke; Joosten, Michel M.; de Jong, Paul E.; Bakker, Stephan J. L.; Gansevoort, Ron T.

    Background-Elevated albuminuria as well as an increased serum uric acid concentration is associated with poor cardiovascular outcome. We questioned whether these 2 variables (albuminuria and serum uric concentration) may be interrelated via tubular uric acid reabsorption. Methods and

  5. EVALUATION OF EVACUATED TUBULAR SOLAR COLLECTORS FOR LARGE SDHW SYSTEMS AND COMBINED SPACE HEATING SYSTEMS

    DEFF Research Database (Denmark)

    Qin, Lin; Furbo, Simon

    1999-01-01

    . Based on thesemodels, the thermal performance of large solar domestic hot water (DHW) systems and combined domestichot water and space heating systems with the four evacuated tubular collectors was determined. To make acomparison with traditional flat-plate collectors, similar simulations were also......In the present study, detailed investigations on evacuated tubular solar collectors for large solarheating systems have been carried out. Four types of evacuated tubular solar collectors were used in theinvestigation. Based on laboratory tests, simulation models for the collectors were determined...... carried out for systems with atypical flat-plate collector. The results show that the thermal advantage of evacuated tubular collectors variesgreatly from system to system, and increases with the solar fraction. Furthermore, the higher the operationtemperature of the collector in the system is...

  6. Tubular adenoma of the breast in a pregnant girl: report on a case.

    Science.gov (United States)

    Palnaes Hansen, C; Fahrenkrug, L; Hastrup, N

    1991-12-01

    A rare case of a tubular breast adenoma in a 13-year-old pregnant girl is presented. The tumor which developed during pregnancy measured 10 x 8 x 4 cm, was well demarcated and could be totally removed.

  7. Central Mound Mastopexy for the Correction of Tuberous/Tubular Breast Deformity

    Directory of Open Access Journals (Sweden)

    Olivia A. Abbate, BA

    2017-11-01

    Full Text Available Summary:. Tuberous and tubular breast deformity are well-recognized abnormalities in the plastic surgery community that incur severe physical and psychological consequences in affected patients. Current reconstructive options for the tuberous and tubular breasts favor the use of prosthetic implants and soft-tissue manipulation. We present a case of tuberous and tubular breast deformity treated with a central mound reduction technique and mastopexy with imbricating sutures without the use of prosthetic implants. The patient remained extremely pleased with her results at long-term follow-up. This represents a unique case of successful reconstruction in a patient with a tuberous and tubular breast deformity using a central mound reduction technique with mastopexy and without a prosthetic device.

  8. CT and US diagnosis of enteric duplication tubular cysts in children

    International Nuclear Information System (INIS)

    Cheng Jianmin; Chen Xiaoming; Yang Xinghui; Wang Qingyang

    2000-01-01

    Objective: To investigate the CT and ultrasonographic characteristics of enteric duplication tubular cyst. Methods: CT and ultrasonography (US) of 6 cases with enteric duplication tubular cyst were analyzed. CT scanning was performed in 5 cases, US in 6 cases and GI in 3 cases. Results: CT revealed cystic lesions with 'soft tissue rim sign', contiguous to a segment of normal bowel (n=5), in which 2 cases demonstrated gas bubbles. The appearance of US was quite similar to CT. There was an anechoic fluid -filled lumen with a double- layered surrounding wall (double wall sign) (n=6), in which 4 cases revealed peristalsis sign. In 1 case GI demonstrated barium-filled cystic tubular dilatation with 'cobblestone' pattern of mucosa. Conclusion: The characteristic CT and US manifestations were highly diagnostic of enteric duplication tubular cyst

  9. Sequential Injection Determination of D-Glucose by Chemiluminescence Using an Open Tubular Immobilised Enzyme Reactor

    DEFF Research Database (Denmark)

    Liu, Xuezhu; Hansen, Elo Harald

    1996-01-01

    A sequential injection analysis system is described that incorporates a nylon tubular reactor containing immobilised glucose oxidase, allowing determination of D-glucose by means of subsequent luminol chemiluminescence detection of the hydrogen peroxide generated in the enzymatic reaction...

  10. 78 FR 52213 - Certain Oil Country Tubular Goods From India, Korea, the Philippines, Saudi Arabia, Taiwan...

    Science.gov (United States)

    2013-08-22

    ... (Preliminary)] Certain Oil Country Tubular Goods From India, Korea, the Philippines, Saudi Arabia, Taiwan... reason of imports from India, Korea, the Philippines, Saudi Arabia, Taiwan, Thailand, Turkey, Ukraine..., Korea, the Philippines, Saudi Arabia, Taiwan, Thailand, Turkey, Ukraine, and Vietnam. Accordingly...

  11. Intrarenal hemodynamics and impaired tubular functions in patients with systemic lupus erythematosus

    Directory of Open Access Journals (Sweden)

    A N Maksudova

    2010-01-01

    Conclusion. The smaller and no RFR in patients without signs of nephropathy may suggest occult intrarenal hemodynamic disorders detected during the dopamine stress test. Tubular impairments in SLE were largely characteristic of patients with intrarenal hemodynamic disorders.

  12. Design and analysis of tubular permanent magnet linear wave generator.

    Science.gov (United States)

    Si, Jikai; Feng, Haichao; Su, Peng; Zhang, Lufeng

    2014-01-01

    Due to the lack of mature design program for the tubular permanent magnet linear wave generator (TPMLWG) and poor sinusoidal characteristics of the air gap flux density for the traditional surface-mounted TPMLWG, a design method and a new secondary structure of TPMLWG are proposed. An equivalent mathematical model of TPMLWG is established to adopt the transformation relationship between the linear velocity of permanent magnet rotary generator and the operating speed of TPMLWG, to determine the structure parameters of the TPMLWG. The new secondary structure of the TPMLWG contains surface-mounted permanent magnets and the interior permanent magnets, which form a series-parallel hybrid magnetic circuit, and their reasonable structure parameters are designed to get the optimum pole-arc coefficient. The electromagnetic field and temperature field of TPMLWG are analyzed using finite element method. It can be included that the sinusoidal characteristics of air gap flux density of the new secondary structure TPMLWG are improved, the cogging force as well as mechanical vibration is reduced in the process of operation, and the stable temperature rise of generator meets the design requirements when adopting the new secondary structure of the TPMLWG.

  13. Design and Analysis of Tubular Permanent Magnet Linear Wave Generator

    Directory of Open Access Journals (Sweden)

    Jikai Si

    2014-01-01

    Full Text Available Due to the lack of mature design program for the tubular permanent magnet linear wave generator (TPMLWG and poor sinusoidal characteristics of the air gap flux density for the traditional surface-mounted TPMLWG, a design method and a new secondary structure of TPMLWG are proposed. An equivalent mathematical model of TPMLWG is established to adopt the transformation relationship between the linear velocity of permanent magnet rotary generator and the operating speed of TPMLWG, to determine the structure parameters of the TPMLWG. The new secondary structure of the TPMLWG contains surface-mounted permanent magnets and the interior permanent magnets, which form a series-parallel hybrid magnetic circuit, and their reasonable structure parameters are designed to get the optimum pole-arc coefficient. The electromagnetic field and temperature field of TPMLWG are analyzed using finite element method. It can be included that the sinusoidal characteristics of air gap flux density of the new secondary structure TPMLWG are improved, the cogging force as well as mechanical vibration is reduced in the process of operation, and the stable temperature rise of generator meets the design requirements when adopting the new secondary structure of the TPMLWG.

  14. Design, analysis, and test of an active tubular interface

    Science.gov (United States)

    Elspass, Wilfried J.; Eerme, M.; Paradies, R.; Resch, Martin

    1997-06-01

    Space missions require higher and higher performance such as high pointing accuracy and stability, and high shape precision. Passive damping means often cannot fulfill the requirements. Besides space applications at the same time numerous applications in machine design require higher accuracy. For a lot of applications the passive measures come up against limits. Active technologies have to be considered more often. Active mechanical components are more and more used as a necessary step towards adaptive structures. Active mechanical interfaces are simpler systems having very useful applications and can be used as kind of test benches in order to master the most exacting technologies. The main advantages of such an active interface are the following: (1) state-of- the-art sensors and actuators can be used, (2) the mechanical design of the interface is conventional, (3) the passive behavior of the system is not deteriorated, (4) the design is compact and rather easy to integrate, (5) easy repair (replacement) of the active mechanical part, (6) standardization of the interfaces results in cost reductions. An important property in such intermediate step is that no major redesign of the conventionally designed mechanical structure should be needed. The design, numerical analysis, manufacturing and test of a fully integrated active tubular interface (ATI) is presented. The design of the ATI includes the optimal laminate stacking sequence with respect to maximum deformation efficiency. The results of an active damping application, an antenna support beam, including the controller layout are discussed.

  15. STUDY THE CREEP OF TUBULAR SHAPED FIBER REINFORCED COMPOSITES

    Directory of Open Access Journals (Sweden)

    Najat J. Saleh

    2013-05-01

    Full Text Available Inpresent work tubular –shaped fiber reinforced composites were manufactured byusing two types of resins ( Epoxy and unsaturated polyester and separatelyreinforced with glass, carbon and kevlar-49 fibers (filament and woven roving,hybrid reinforcement composites of these fibers were also prepared. The fiberswere wet wound on a mandrel using a purposely designed winding machine,developed by modifying an ordinary lathe, in winding angle of 55° for filament. A creep test was made of either the fulltube or specimens taken from it. Creep was found to increase upon reinforcementin accordance to the rule of mixture and mainly decided by the type of singleor hybridized fibers. The creep behavior, showed that the observed strain tendsto appear much faster at higher temperature as compared with that exhibited atroom temperate. The creep rate also found to be depending on fiber type, matrixtype, and the fiber /matrix bonding. The creep energy calculated fromexperimental observations was found to exhibit highest value for hybridizedreinforcement.

  16. The tubular separate first wall for ITER EDA

    International Nuclear Information System (INIS)

    Pizzuto, A.; Riccardi, B.; Salpietro, E.

    1994-01-01

    The first wall is one of the most loaded plasma-facing components, the heat flux is such that the thermal stresses are the most important design concern. In addition, the First Wall shall resist the eddy current induced plasma disruption, the high pressure of the coolant without leaking ( -6 Torr-lit/sec.) and it should maintain its properties under fast neutron flux (dose up to 3 MW/m 2 ). The tubular solution is the most suitable one to cope with the thermal stresses, the use of double wall reduces the risk of leaks inside the vacuum vessel by avoiding the growth of a crack through both walls: the soft brazing in between walls stops the growth of a crack from one tube to the other. The eddy currents induced in the tubes are low and the Halo current flowing poloidally in the tubes exert a radial pressure which is supported by the blanket box via ad hoc supporting points provided in between first wall and blanket. Conclusions from the thermo-hydraulic analysis and the electromagnetic analysis will be presented including dynamic analysis. Also results of preliminary technological tests on coatings will be discussed

  17. Phorbol esters inhibit ammoniagenesis and gluconeogenesis in proximal tubular segments

    Energy Technology Data Exchange (ETDEWEB)

    Chobanian, M.C.; Hammerman, M.R.

    1987-06-01

    To characterize the regulation of ammoniagenesis and gluconeogenesis in renal proximal tubule, ammonia and glucose productions were measured in suspension of canine proximal tubular segments incubated with 10 mM L-glutamine. Productions were linear functions of time for 120 min and were decreased as extracellular pH was increased from 7.0 to 7.5. To ascertain whether activation of protein kinase c affects either process, the authors incubated segments with tumor-promoting phorbol esters, 12-O-tetradecanoylphorbol-13-acetate (TPA), or phorbol 12,13-dibutyrate, or with the inactive phorbol ester 4..cap alpha..-phorbol. Ammoniagenesis and gluconeogenesis were inhibited by incubation with 10/sup /minus/6/M of the two former compounds but not the latter compound. Phorbol ester-induced inhibition was observed under conditions such that extracellular (Na/sup +/) was greater than intracellular (Na/sup +/), but not when extracellular (Na/sup +/) equaled intracellular (Na/sup +/), and was not observed in the presence of amiloride. These findings are consistent with a role for protein kinase c in the control of ammoniagenesis and gluconeogenesis in proximal tubule. Such control could be mediated via stimulation of Na/sup 1/-H/sup +/ exchange.

  18. Multimodal transport and dispersion of organelles in narrow tubular cells

    Science.gov (United States)

    Mogre, Saurabh S.; Koslover, Elena F.

    2018-04-01

    Intracellular components explore the cytoplasm via active motor-driven transport in conjunction with passive diffusion. We model the motion of organelles in narrow tubular cells using analytical techniques and numerical simulations to study the efficiency of different transport modes in achieving various cellular objectives. Our model describes length and time scales over which each transport mode dominates organelle motion, along with various metrics to quantify exploration of intracellular space. For organelles that search for a specific target, we obtain the average capture time for given transport parameters and show that diffusion and active motion contribute to target capture in the biologically relevant regime. Because many organelles have been found to tether to microtubules when not engaged in active motion, we study the interplay between immobilization due to tethering and increased probability of active transport. We derive parameter-dependent conditions under which tethering enhances long-range transport and improves the target capture time. These results shed light on the optimization of intracellular transport machinery and provide experimentally testable predictions for the effects of transport regulation mechanisms such as tethering.

  19. Design and Analysis of Tubular Permanent Magnet Linear Wave Generator

    Science.gov (United States)

    Si, Jikai; Feng, Haichao; Su, Peng; Zhang, Lufeng

    2014-01-01

    Due to the lack of mature design program for the tubular permanent magnet linear wave generator (TPMLWG) and poor sinusoidal characteristics of the air gap flux density for the traditional surface-mounted TPMLWG, a design method and a new secondary structure of TPMLWG are proposed. An equivalent mathematical model of TPMLWG is established to adopt the transformation relationship between the linear velocity of permanent magnet rotary generator and the operating speed of TPMLWG, to determine the structure parameters of the TPMLWG. The new secondary structure of the TPMLWG contains surface-mounted permanent magnets and the interior permanent magnets, which form a series-parallel hybrid magnetic circuit, and their reasonable structure parameters are designed to get the optimum pole-arc coefficient. The electromagnetic field and temperature field of TPMLWG are analyzed using finite element method. It can be included that the sinusoidal characteristics of air gap flux density of the new secondary structure TPMLWG are improved, the cogging force as well as mechanical vibration is reduced in the process of operation, and the stable temperature rise of generator meets the design requirements when adopting the new secondary structure of the TPMLWG. PMID:25050388

  20. Transport Mean Free Path for Magneto-Transverse Light Diffusion

    OpenAIRE

    Lacoste, D.; van Tiggelen, B. A.

    1998-01-01

    We derive an expression for the transport mean free path $\\ell^*_\\perp$ associated with magneto-transverse light diffusion for a random collection of Faraday-active Mie scatterers. This expression relates the magneto-transverse diffusion in multiple scattering directly to the magneto-transverse scattering of a single scatterer.

  1. Longitudinal and transverse polarizations in the deep inelastic reactions

    International Nuclear Information System (INIS)

    Bressan, A.

    1996-07-01

    This course is an introduction to the dominant effects of longitudinal and transverse spin in deep inelastic reactions. Only the effects present to the 'leading twist' are attacked. The mass and transverse impulsion of partons are neglected. We will attach to bring out the respective specificities of longitudinal and transverse polarizations. (N.C.)

  2. Evaluation of Transverse Lie at Term by Ultrasonography | Oyinloye ...

    African Journals Online (AJOL)

    Context: Transverse lie at term may have adverse consequences on both the mother and the foetus. Evaluating transverse lie at term by ultrasonography may reduce these adverse consequences and improve both the maternal and fetal outcome. Objectives: To determine predisposing factors to persistent transverse lie at ...

  3. Design and performance of tubular flat-plate solid oxide fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Matsushima, T.; Ikeda, D.; Kanagawa, H. [NTT Integrated Information & Energy Systems Labs., Tokyo (Japan)] [and others

    1996-12-31

    With the growing interest in conserving the environmental conditions, much attention is being paid to Solid Oxide Fuel Cell (SOFC), which has high energy-conversion efficiency. Many organizations have conducted studies on tubular and flat type SOFCs. Nippon Telegraph and Telephone Corporation (NTT) has studied a combined tubular flat-plate SOFC, and already presented the I-V characteristics of a single cell. Here, we report the construction of a stack of this SOFC cell and successful generation tests results.

  4. Effect of arteriography on renal tubular function measured by scintiscans with hippuran

    International Nuclear Information System (INIS)

    Collard, M.; Guey, A.; Claveyrolas, P.; Mendoza, M.; Traeger, J.; Lyonnet, D.; Pinet, A.

    1978-01-01

    The effect of renal arteriography on tubular function was studied in six subjects during scintiscans with hippuran. This compound can be extracted from, but is only slight excreted by, the tubular cells. The following parameters were studied: extraction per unit of surface area and renal volume; secretion; renal surface area. No significant differences were observed between the values obtained before and after angiography, in the small number of cases studied [fr

  5. Tubular cross talk in acute kidney injury: a story of sense and sensibility

    OpenAIRE

    El-Achkar, Tarek M.; Dagher, Pierre C.

    2015-01-01

    The mammalian kidney is an organ composed of numerous functional units or nephrons. Beyond the filtering glomerulus of each nephron, various tubular segments with distinct populations of epithelial cells sequentially span the kidney from cortex to medulla. The highly organized folding of the tubules results in a spatial distribution that allows intimate contact between various tubular subsegments. This unique arrangement can promote a newly recognized type of horizontal epithelial-to-epitheli...

  6. Renal tubular dysfunction presenting as recurrent hypokalemic periodic quadriparesis in systemic lupus erythematosus

    Directory of Open Access Journals (Sweden)

    D Prasad

    2014-01-01

    Full Text Available We report recurrent hypokalemic periodic quadriparesis in a 30-year-old woman. Patient had also symptoms of multiple large and small joint pain, recurrent oral ulceration, photosensitivity and hair loss that were persisting since last 6 months and investigations revealed systemic lupus erythematosus (SLE with distal tubular acidosis. Our patient was successfully treated with oral potassium chloride, sodium bicarbonate, hydroxychloroquine and a short course of steroids. Thus, tubular dysfunction should be carefully assessed in patients with SLE.

  7. Osteosynthesis in surgical treatment of metastatic lesions of long tubular bones

    OpenAIRE

    RADCHENKO A.I.; ZHUKOVEC A.G.; BOGDAEV Y.M.

    2017-01-01

    Objectives. This study was designed to investigate the causes and risk factors of complications requiring revision surgeries after intramedullary and plate osteosynthesis of the long tubular bones affected by metastases. Methods. Surgical treatment outcomes of patients with long tubular bones metastases (n=44) were analyzed retrospectively. Twelve patients had solitary skeletal metastasis, eleven multiple, twenty one bone metastases combined with visceral metastases. The pathological fracture...

  8. Effect of cisplatin on renal haemodynamics and tubular function in the dog kidney

    DEFF Research Database (Denmark)

    Daugaard, G; Abildgaard, U; Holstein-Rathlou, N H

    1987-01-01

    Administration of cisplatin (5 mg/kg) to dogs results in polyuric renal failure due initially to a proximal tubular functional impairment. 48-72 h after the cisplatin administration the depressed renal function can be attributed to impairment of proximal as well as distal tubular reabsorptive...... capacities associated with increased renal vascular resistance. The polyuria seems to be due to the impaired reabsorption rate in the distal nephron segments....

  9. Robotic membranes

    DEFF Research Database (Denmark)

    Ramsgaard Thomsen, Mette

    2008-01-01

    , Vivisection and Strange Metabolisms, were developed at the Centre for Information Technology and Architecture (CITA) at the Royal Danish Academy of Fine Arts in Copenhagen as a means of engaging intangible digital data with tactile physical material. As robotic membranes, they are a dual examination...

  10. Construção e avaliação de um eletrodo tubular sensível ao íon hidrogênio como detector em sistemas de análise em fluxo

    Directory of Open Access Journals (Sweden)

    Martelli Patrícia B.

    1998-01-01

    Full Text Available The construction of a tubular hydrogen ion-selective potentiometric electrode without inner reference solution, based on the tridodecylamine (TDDA ionophore, and its evaluation in a flow system are described. TDDA was dissolved in 2-nitrophenyl octyl ether, dispersed in a PVC membrane and applied directly to a conducting support which consisted of an epoxy resin and graphite mixture. The electrode was designed with a tubular geometry to effort facilities to be coupled as part of a flow injection network. The main working characteristics such as response time, linear pH range, selectivity and life time were evaluated and compared with those obtained which a conventionally shaped electrode based on the same sensor. The electrode showed a slope of 51-52 mV dec-1 within a linear pH range from 4.0 up to 12.0.

  11. Cadmium and cisplatin damage erythropoietin-producing proximal renal tubular cells

    Energy Technology Data Exchange (ETDEWEB)

    Horiguchi, Hyogo; Oguma, Etsuko; Kayama, Fujio [Jichi Medical School, Division of Environmental Medicine, Center for Community Medicine, Tochigi (Japan); Core Research for Evolutional Science and Technology, Japan Science Technology Corporation (CREST-JST), Saitama (Japan)

    2006-10-15

    The concomitant manifestations of proximal renal tubular dysfunction and anemia with erythropoietin (Epo) deficiency observed in chronic cadmium (Cd) intoxication, such as Itai-itai disease, suggest a close local correlation between the Cd-targeted tubular cells and Epo-producing cells in the kidney. Therefore, we investigated the local relationship between hypoxia-induced Epo production and renal tubular injury in rats injected with Cd at 2 mg/kg twice a week for 8 months. Anemia due to insufficient production of Epo was observed in Cd-intoxicated rats. In situ hybridization detected Epo mRNA expression in the proximal renal tubular cells of hypoxic rats without Cd intoxication, and the Cd-intoxicated rats showed atrophy of Epo-expressing renal tubules and replacement of them with fibrotic tissue. A single dose of cisplatin at 8 mg/kg, which can induce clinical manifestations similar to those of Cd including renal tubular damage along with Epo-deficient anemia, resulted in Epo-expressing renal tubule destruction on day 4. These data indicate that Cd and cisplatin would induce anemia through the direct injury of the proximal renal tubular cells that are responsible for Epo production. (orig.)

  12. Prevalence of renal tubular dysfunction in beta thalassemia minor in shiraz

    Directory of Open Access Journals (Sweden)

    Ali Moradi Nakhodcheri

    2012-02-01

    Full Text Available  Background & objective: β-Thalassemia minor is an asymptomatic hereditary disease. The first study on the relation of renal tubular dysfunction and β-thalassemia minor was performed in 2002 but those studies seem inadequate.The main goal of this study is through evaluation of renal tubular function in 100 patients with thalassemia minor. Materials & Methods: 100 patients with β- thalassemia which confirmed by hemoglobin electrophoresis and CBC as well as RBC indices were studied.14 out of 100 cases exit because of Urinary Tract Infection, diabetes mellitus or hypertension.Complete chemistry profile was performed on serum and urine of all reminder 86 patients (46 female and 40 male. Patients classified into two groups: β-thalassemia minor with anemia and without anemia. Another control group include 50 healthy individuals also considered.Then data analyzed by proper statistical methods. Results: 20 out of 86 reminder cases e.g. 24% showed at least one index of renal tubular dysfunction.58% of patients was been anemic and 42% non anemic. The most prominent tubular dysfunction was seen in a 29 years old lady with glucosuria and without anemia. conclusion: β-Thalassemia minor is common in Iran specially in Fars province. This study revealed significant renal tubular dysfunction in patient with β-thalassemia minor. So it is necessary to check out thalassemic patients for renal function tests periodically. Key words: β-thalassemia, minor,renal tubular dysfunction

  13. pH measurement of tubular vacuoles of an arbuscular mycorrhizal fungus, Gigaspora margarita.

    Science.gov (United States)

    Funamoto, Rintaro; Saito, Katsuharu; Oyaizu, Hiroshi; Aono, Toshihiro; Saito, Masanori

    2015-01-01

    Arbuscular mycorrhizal fungi play an important role in phosphate supply to the host plants. The fungal hyphae contain tubular vacuoles where phosphate compounds such as polyphosphate are accumulated. Despite their importance for the phosphate storage, little is known about the physiological properties of the tubular vacuoles in arbuscular mycorrhizal fungi. As an indicator of the physiological state in vacuoles, we measured pH of tubular vacuoles in living hyphae of arbuscular mycorrhizal fungus Gigaspora margarita using ratio image analysis with pH-dependent fluorescent probe, 6-carboxyfluorescein. Fluorescent images of the fine tubular vacuoles were obtained using a laser scanning confocal microscope, which enabled calculation of vacuolar pH with high spatial resolution. The tubular vacuoles showed mean pH of 5.6 and a pH range of 5.1-6.3. These results suggest that the tubular vacuoles of arbuscular mycorrhizal fungi have a mildly acidic pH just like vacuoles of other fungal species including yeast and ectomycorrhizal fungi.

  14. Human embryonic stem cells differentiate into functional renal proximal tubular-like cells.

    Science.gov (United States)

    Narayanan, Karthikeyan; Schumacher, Karl M; Tasnim, Farah; Kandasamy, Karthikeyan; Schumacher, Annegret; Ni, Ming; Gao, Shujun; Gopalan, Began; Zink, Daniele; Ying, Jackie Y

    2013-04-01

    Renal cells are used in basic research, disease models, tissue engineering, drug screening, and in vitro toxicology. In order to provide a reliable source of human renal cells, we developed a protocol for the differentiation of human embryonic stem cells into renal epithelial cells. The differentiated stem cells expressed markers characteristic of renal proximal tubular cells and their precursors, whereas markers of other renal cell types were not expressed or expressed at low levels. Marker expression patterns of these differentiated stem cells and in vitro cultivated primary human renal proximal tubular cells were comparable. The differentiated stem cells showed morphological and functional characteristics of renal proximal tubular cells, and generated tubular structures in vitro and in vivo. In addition, the differentiated stem cells contributed in organ cultures for the formation of simple epithelia in the kidney cortex. Bioreactor experiments showed that these cells retained their functional characteristics under conditions as applied in bioartificial kidneys. Thus, our results show that human embryonic stem cells can differentiate into renal proximal tubular-like cells. Our approach would provide a source for human renal proximal tubular cells that are not affected by problems associated with immortalized cell lines or primary cells.

  15. Hyperammonemia associated with distal renal tubular acidosis or urinary tract infection: a systematic review.

    Science.gov (United States)

    Clericetti, Caterina M; Milani, Gregorio P; Lava, Sebastiano A G; Bianchetti, Mario G; Simonetti, Giacomo D; Giannini, Olivier

    2018-03-01

    Hyperammonemia usually results from an inborn error of metabolism or from an advanced liver disease. Individual case reports suggest that both distal renal tubular acidosis and urinary tract infection may also result in hyperammonemia. A systematic review of the literature on hyperammonemia secondary to distal renal tubular acidosis and urinary tract infection was conducted. We identified 39 reports on distal renal tubular acidosis or urinary tract infections in association with hyperammonemia published between 1980 and 2017. Hyperammonemia was detected in 13 children with distal renal tubular acidosis and in one adult patient with distal renal tubular acidosis secondary to primary hyperparathyroidism. In these patients a negative relationship was observed between circulating ammonia and bicarbonate levels (P urinary tract infection was complicated by acute hyperammonemia and symptoms and signs of acute neuronal dysfunction, such as an altered level of consciousness, convulsions and asterixis, often associated with signs of brain edema, such as anorexia and vomiting. Urea-splitting bacteria were isolated in 28 of the 31 cases. The urinary tract was anatomically or functionally abnormal in 30 of these patients. This study reveals that both altered distal renal tubular acidification and urinary tract infection may be associated with relevant hyperammonemia in both children and adults.

  16. Ground Vibration Isolation of Multiple Scattering by Using Rows of Tubular Piles as Barriers

    Directory of Open Access Journals (Sweden)

    Miao-miao Sun

    2014-01-01

    Full Text Available A new formal solution for the multiple scattering of plane harmonic waves by a group of arbitrary configuration tubular piles in an elastic total space is derived. Each order of scattering satisfies prescribed boundary conditions at the interface of tubular piles, which is delivered as the sum of incident and scattering waves. The first order performs the scattering wave by each scattered pile and the subsequent orders resulted from the excitation of each pile of first order of scattering from the remaining tubular piles. Advanced scattering orders can be regarded as the same manners. Several series of scattering coefficients are figured out with the aids of addition theorem so that the exact steady-state solution for the scattered displacement and stress is obtained. Particularly, when internal diameter of tubular piles tends to be infinitely small, it degenerates to a solid pile problem. By imposing the normalized displacement amplitudes and transmissibility indices, the influences of specific parameters such as scattering orders, internal and external diameter ratio of piles, pile material rigidity, position and distances between tubular pile and pile rows, and pile numbers are discussed. Certain recommended conclusions have been drawn as the guidelines of practical engineering design for discontinuous barrier of tubular piles.

  17. Tubular kidney injury molecule-1 in protein-overload nephropathy

    NARCIS (Netherlands)

    van Timmeren, Mirjan M.; Bakker, Stephan J. L.; Vaidya, Vishal S.; Bailly, Veronique; Schuurs, Theo A.; Damman, Jeffrey; Stegeman, Coen A.; Bonventre, Joseph V.; van Goor, Harry

    Kim-1, a recently discovered membrane protein, is undetectable in normal kidneys but markedly induced in proximal tubules after ischemic and toxic injury. The function of Kim-1 is unclear, but it is implicated in damage/repair processes. The Kim-1 ectodomain is cleaved by metalloproteinases and

  18. Oxygen Transport Membranes

    Energy Technology Data Exchange (ETDEWEB)

    S. Bandopadhyay

    2008-08-30

    small polaron conduction mechanism. Scanning transmission electron microscopy (STEM) and electron energy loss spectroscopy (EELS) were used to develop strategies to detect and characterize vacancy creation, dopant segregations and defect association in the oxygen conducting membrane material. The pO{sub 2} and temperature dependence of the conductivity, non-stoichiometry and thermal-expansion behavior of compositions with increasing complexity of substitution on the perovskite A and B sites were studied. Studies with the perovskite structure show anomalous behavior at low oxygen partial pressures (<10{sup -5} atm). The anomalies are due to non-equilibrium effects and can be avoided by using very strict criteria for the attainment of equilibrium. The slowness of the oxygen equilibration kinetics arises from two different mechanisms. In the first, a two phase region occurs between an oxygen vacancy ordered phase such as brownmillerite SrFeO{sub 2.5} and perovskite SrFeO{sub 3-x}. The slow kinetics is associated with crossing the two phase region. The width of the miscibility gap decreases with increasing temperature and consequently the effect is less pronounced at higher temperature. The preferred kinetic pathway to reduction of perovskite ferrites when the vacancy concentration corresponds to the formation of significant concentrations of Fe{sup 2+} is via the formation of a Ruddlesden-Popper (RP) phases as clearly observed in the case of La{sub 0.5}Sr{sub 0.5}FeO{sub 3-x} where LaSrFeO{sub 4} is found together with Fe. In more complex compositions, such as LSFTO, iron or iron rich phases are observed locally with no evidence for the presence of discrete RP phase. Fracture strength of tubular perovskite membranes was determined in air and in reducing atmospheric conditions. The strength of the membrane decreased with temperature and severity of reducing conditions although the strength distribution (Weibull parameter, m) was relatively unaltered. Surface and volume

  19. Welding simulation and fatigue assessment of tubular K-joints in high-strength steel

    International Nuclear Information System (INIS)

    Zamiri Akhlaghi, F.

    2014-01-01

    Application of newly developed high strength steel hollow sections is increasing in construction industry – especially for bridge structures – due to their satisfactory material properties and fabrication advantages. These sections allow for longer spans, more slender structures. Savings in weight and volume of material compared to traditional steel grades increase sustainability of construction and compensate for part of higher unit cost of material. Nevertheless, use of high strength steels cannot be promoted unless potential fatigue issues are properly addressed. Two fabrication methods are currently available for the planar Warren trusses made of circular hollow sections (CHS): welding the tubes together, or using cast steel nodes and connecting truss members to them by girth welds. Previous research on tubular bridge trusses indicates that the problematic fatigue cracking sites for the first fabrication method are located at weld toes in the gap region of the truss joints. For the second method, cracking occurs at the root of CHS–cast butt welds. Fatigue performance of these two methods were investigated by constant amplitude fatigue testing of two full scale trusses made of steel grade S690QH and with a geometry similar to previous S355J2H investigation. Fatigue lives of K-joints were in agreement with current recommended code values. For CHS–cast welded connections, no visible cracking was observed up to 2£10 6 cycles. Due to the effect of residual stresses, fatigue cracking was observed in compressive joints as well as tensile joints. Indeed, tensile welding residual stresses keep the crack open during all or part of the compressive load cycle. Their distribution and impact on fatigue life of tubular joints has not been fully investigated before for a complex detail such as Tubular K-joint made of high strength steel. Experimental and numerical methods were utilized for assessment of welding residual stresses. Neutron diffraction experiments were

  20. Welding simulation and fatigue assessment of tubular K-joints in high-strength steel

    Energy Technology Data Exchange (ETDEWEB)

    Zamiri Akhlaghi, F.

    2014-07-01

    Application of newly developed high strength steel hollow sections is increasing in construction industry – especially for bridge structures – due to their satisfactory material properties and fabrication advantages. These sections allow for longer spans, more slender structures. Savings in weight and volume of material compared to traditional steel grades increase sustainability of construction and compensate for part of higher unit cost of material. Nevertheless, use of high strength steels cannot be promoted unless potential fatigue issues are properly addressed. Two fabrication methods are currently available for the planar Warren trusses made of circular hollow sections (CHS): welding the tubes together, or using cast steel nodes and connecting truss members to them by girth welds. Previous research on tubular bridge trusses indicates that the problematic fatigue cracking sites for the first fabrication method are located at weld toes in the gap region of the truss joints. For the second method, cracking occurs at the root of CHS–cast butt welds. Fatigue performance of these two methods were investigated by constant amplitude fatigue testing of two full scale trusses made of steel grade S690QH and with a geometry similar to previous S355J2H investigation. Fatigue lives of K-joints were in agreement with current recommended code values. For CHS–cast welded connections, no visible cracking was observed up to 2£10{sup 6} cycles. Due to the effect of residual stresses, fatigue cracking was observed in compressive joints as well as tensile joints. Indeed, tensile welding residual stresses keep the crack open during all or part of the compressive load cycle. Their distribution and impact on fatigue life of tubular joints has not been fully investigated before for a complex detail such as Tubular K-joint made of high strength steel. Experimental and numerical methods were utilized for assessment of welding residual stresses. Neutron diffraction experiments

  1. Catalytic Dehydrogenation of Ethane in Hydrogen Membrane Reactor

    Science.gov (United States)

    Galuszka, Jan; Giddings, Terry; Clelland, Ian

    The effect of a hydrogen permselective membrane (H-membrane) reactor on catalytic dehydrogenation of ethane was assessed using a fixed bed conventional reactor and a double tubular H-membrane reactor. A 5.0wt.% Cr2O3/γ-Al2O3 catalyst prepared by incipient wetness impregnation of a γ-Al2O3 (BET surface area = 50 m2/g) support was used at 555°C and 600°C. Although about 40% of H2 produced during dehydrogenation of ethane in the membrane reactor passed through the membrane, only moderate enhancement in ethane conversion was observed. The slow processes on the catalyst surface are thought to counterbalance the positive effect of membrane assisted hydrogen removal. Also, decreased selectivity to ethylene due to enhanced carbon formation in the membrane reactor led to faster deactivation of the catalyst. A strategy for commercialization of catalytic dehydrogenation of ethane through the development of a better hydrogen membrane might require a reevaluation.

  2. Copper deposition on Pd membranes by electroless plating

    Energy Technology Data Exchange (ETDEWEB)

    Acha, E.; Arias, P.L.; Cambra, J.F. [Chemical Engineering and Environmental Department, University of the Basque Country, UPV/EHU, 48013 Bilbao (Spain); Van Delft, Y.; Overbeek, J. [Energy Research Centre of the Netherlands ECN, Petten (Netherlands)

    2011-10-15

    PdCu membranes were prepared by the electroless plating of Pd membranes prepared on ceramic tubular supports. Different PdCu membranes were prepared with Pd content between 45 and 77 wt% and a total metal layer between 0.5 and 1.9 {mu}m thickness. The alloying step was performed in two ways to compare and establish the required alloying time for obtaining high permeance membranes. The alloying was analysed with EDX composition measurements, and full alloying was not required to obtain a stable hydrogen flux. Finally, permeance tests were performed at different pressures, including temperature cycles in hydrogen and nitrogen, to observe membrane stability. The hydrogen permeance values of the membranes were high, between 1.5x10{sup -3} and 4.5x10{sup -3} mol/(s Pa{sup 0.5} m{sup 2}) at 673 K. The membranes recorded stable permeance values even after thermal cycles in a hydrogen atmosphere. Metal layer thickness was calculated using both the weight difference method and SEM images. SEM images were also used to analyse the surface morphology of the membranes, which was generally fairly uniform and smooth.

  3. Treatment of a Recurrent Vaginal Obstruction With a Modified Mold After an Excision of a Transverse Vaginal Septum

    Directory of Open Access Journals (Sweden)

    I Wayan Megadhana

    2016-06-01

    Full Text Available Background: A vaginal obstruction often occurs as a complication in women who had previously undergone an excision of a transverse vaginal septum. The use of a mold coated with membranes in the correction surgery provides a good healing prognosis. Objective: To report a case of a treatment of a recurrent vaginal obstruction with a modified mold after undergoing an excision of a transverse vaginal septum in a 15-year-old woman. Result: A follow-up on the patient, four months after using the modified mold, showed a regular menstrual cycles without a sign of vaginal narrowing, an infection, nor a complaint. Conclusion: The treatment using a modified mold, for a recurrent vaginal obstruction after an excision of a transverse vaginal septum, is a new innovation with a satisfactory result.

  4. Generating catalogs of transverse matching solutions

    International Nuclear Information System (INIS)

    Swain, G.; Busch, P.; Burns, M.

    1989-01-01

    Programs such as TRANSPORT or TRACE can find transverse beam matching solutions one at a time when given appropriate starting conditions. In the present work, an algorithm is described which rapidly finds a catalog of approximate transverse beam matching solutions. For a given initial beam, the algorithm finds the gradients of four quadrupole magnets such as to get four Twiss parameters (alpha and beta for horizontal and vertical planes) which are close to a set of desired values at the exit of a constant-energy beam line with no horizontal-vertical cross coupling and no space charge. The beam line may contain bending elements with edge corrections and other elements for which the r matrixes are known. The algorithm transforms the entrance and exit beam specifications to waist specifications, and uses the properties of waist-to-waist transport to reduce the problem from a four dimensional search to a two dimensional search. At the Los Alamos Meson Physics Facility (LAMPF) accelerator, transverse matching is important in the low-energy transport lines (0.75 MeV), where beams from the H + , H/sup /minus//, and polarized H/sup /minus// sources must be tailored for injection into the drift-tube linac; and in the transition region (100 MeV), where the beam from the drift-tube linac is injected into the side-coupled linac. Space charge has significant effects in the low-energy transport, but it is still valuable to get no-space-charge matching solutions as a starting point for solutions with space charge. 2 refs

  5. Subacute transverse myelitis with Lyme profile dissociation

    Directory of Open Access Journals (Sweden)

    Ajjan, Mohammed

    2008-06-01

    Full Text Available Introduction: Transverse myelitis is a very rare neurologic syndrome with an incidence per year of 1-5 per million population. We are presenting an interesting case of subacute transverse myelitis with its MRI (magnetic resonance imaging and CSF (cerebrospinal fluid findings. Case: A 46-year-old African-American woman presented with decreased sensation in the lower extremities which started three weeks ago when she had a 36-hour episode of sore throat. She reported numbness up to the level just below the breasts. Lyme disease antibodies total IgG (immunoglobulin G and IgM (immunoglobulin M in the blood was positive. Antinuclear antibody profile was within normal limits. MRI of the cervical spine showed swelling in the lower cervical cord with contrast enhancement. Cerebrospinal fluid was clear with negative Borrelia Burgdorferi IgG and IgM. Herpes simplex, mycoplasma, coxiella, anaplasma, cryptococcus and hepatitis B were all negative. No oligoclonal bands were detected. Quick improvement ensued after she was given IV Ceftriaxone for 7 days. The patient was discharged on the 8th day in stable condition. She continued on doxycycline for 21 days. Conclusions: Transverse myelitis should be included in the differential diagnosis of any patient presenting with acute or subacute myelopathy in association with localized contrast enhancement in the spinal cord especially if flu-like prodromal symptoms were reported. Lyme disease serology is indicated in patients with neurological symptoms keeping in mind that dissociation in Lyme antibody titers between the blood and the CSF is possible.

  6. A Survey for Transverse Nasal Groove

    Directory of Open Access Journals (Sweden)

    K Pavithran

    1989-01-01

    Full Text Available Out of 3000 consecutive subjects surveyed for the typical lesion of transverse nasal groove, 180 were found to have the characteristic lesions. In LU patients, the floor of the groove was studded with patulous hair follicles, greasy sale and black comedones. The age of the patients varied from 16 to 45 years, the majority belonged to the 20 to 30 age group. Family occurrence of the groove was noted ′in only 7.Seboffhoeic dermatitis, pityriasis versicolor and acne vulgaris were the commonly associated diseases.

  7. Idiopathic intracranial hypertension and transverse sinus stenoses

    DEFF Research Database (Denmark)

    Skyrman, Simon; Fytagoridis, Anders; Andresen, Morten

    2013-01-01

    An 18-year-old woman was diagnosed with idiopathic intracranial hypertension (IIH) and bilateral transverse sinus stenoses (TSS), after presenting with papilledema and decreased visual acuity. Lumbar puncture revealed an opening pressure of >60 cm H2O. MRI showed bilateral TSS believed to be asso...... was inserted since the patient had improved with CSF diversion. MRI verified reopening of the venous sinuses after shunt placement, and the patient remains asymptomatic with no signs of relapse after 3 years of follow-up....

  8. Transverse entanglement migration in Hilbert space

    International Nuclear Information System (INIS)

    Chan, K. W.; Torres, J. P.; Eberly, J. H.

    2007-01-01

    We show that, although the amount of mutual entanglement of photons propagating in free space is fixed, the type of correlations between the photons that determine the entanglement can dramatically change during propagation. We show that this amounts to a migration of entanglement in Hilbert space, rather than real space. For the case of spontaneous parametric down-conversion, the migration of entanglement in transverse coordinates takes place from modulus to phase of the biphoton state and back again. We propose an experiment to observe this migration in Hilbert space and to determine the full entanglement

  9. Interacting dark sector with transversal interaction

    Energy Technology Data Exchange (ETDEWEB)

    Chimento, Luis P.; Richarte, Martín G. [Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and IFIBA, CONICET, Ciudad Universitaria, Pabellón I, Buenos Aires 1428 (Argentina)

    2015-03-26

    We investigate the interacting dark sector composed of dark matter, dark energy, and dark radiation for a spatially flat Friedmann-Robertson-Walker (FRW) background by introducing a three-dimensional internal space spanned by the interaction vector Q and solve the source equation for a linear transversal interaction. Then, we explore a realistic model with dark matter coupled to a scalar field plus a decoupled radiation term, analyze the amount of dark energy in the radiation era and find that our model is consistent with the recent measurements of cosmic microwave background anisotropy coming from Planck along with the future constraints achievable by CMBPol experiment.

  10. Splitting Functions at High Transverse Momentum

    CERN Document Server

    Moutafis, Rhea Penelope; CERN. Geneva. TH Department

    2017-01-01

    Among the production channels of the Higgs boson one contribution could become significant at high transverse momentum which is the radiation of a Higgs boson from another particle. This note focuses on the calculation of splitting functions and cross sections of such processes. The calculation is first carried out on the example $e\\rightarrow e\\gamma$ to illustrate the way splitting functions are calculated. Then the splitting function of $e\\rightarrow eh$ is calculated in similar fashion. This procedure can easily be generalized to processes such as $q\\rightarrow qh$ or $g\\rightarrow gh$.

  11. Asymmetrical transverse structures in nonlinear interferometers

    CERN Document Server

    Romanov, O G

    2003-01-01

    The work presents a novel type of optical instability, which leads to the spontaneous formation of a stationary or pulsating asymmetrical structure in the problem of interaction between two counterpropagating waves in a ring cavity with Kerr-like nonlinearity. Linear stability analysis of interferometer transmission stationary states enabled: (1) to mark out typical bifurcations for this system: self- and cross-modulational instabilities, (2) to determine the range of parameters for which the symmetry breaking of transverse structures and complex temporal behaviour of the light field could be observed. The predictions of linear stability analysis have been verified with numerical modelling of coupled-modes equations.

  12. Transversity GPD in photo- and electroproduction of two vectormesons

    Energy Technology Data Exchange (ETDEWEB)

    Enberg, Rikard; Pire, Bernard; Szymanowski, Lech

    2006-01-17

    The chiral-odd generalized parton distribution (GPD), or transversity GPD, of the nucleon can be accessed experimentally through the photo- or electroproduction of two vector mesons on a polarized nucleon target, {gamma}{sup (*)}N {yields} {rho}{sub 1}{rho}{sub 2}N', where {rho}{sub 1} is produced at large transverse momentum, {rho}{sub 2} is transversely polarized, and the mesons are separated by a large rapidity gap. We predict the cross section for this process for both transverse and longitudinal {rho}{sub 2} production. To this end we propose a model for the transversity GPDH{sub T}(x,{zeta},t), and give an estimate of the relative sizes of the transverse and longitudinal {rho}{sub 2}cross sections. We show that a dedicated experiment at high energy should be able to measure the transversity content of the proton.

  13. MR imaging of alar and transverse atlantal ligament injuries

    Energy Technology Data Exchange (ETDEWEB)

    Echigoya, Naoki; Harata, Seiko; Ueyama, Kazumasa (Hirosaki Univ., Aomori (Japan). School of Medicine); Nakano, Keisuke

    1992-06-01

    Autopsy findings of ligaments of the upper cervical spine were compared with magnetic resonance imaging (MRI) findings. Ligaments were clearly shown as hypointensity on T1-weighted images and proton density images. Transverse images were useful in diagnosing alar and transverse atlantal ligament injuries. When there is a bilateral difference in the alar ligaments, ruptured ligament is suspected. Transverse ligament rupture was shown on interrupted hypointensity and as hyperintensity. MRI was capable of diagnosing alar ligament rupture in 8 of 11 patients, and transverse ligament rupture in all 3 patients. In 2 patients having Jefferson's fracture and injuried atlanoaxial subluxation encountered in the clinical practice, transverse ligament rupture was similarly observed as that in autopsy cases on MR images. Hyperintensity in the transverse ligament rupture area was seen even one year after injury. Injured transverse ligament was seen as swollen hyperintensity on sagittal images; and the hyperintensity was gradually decreased with the process of healing. (N.K.).

  14. Perfluorooctanesulfonate Mediates Renal Tubular Cell Apoptosis through PPARgamma Inactivation.

    Directory of Open Access Journals (Sweden)

    Li-Li Wen

    Full Text Available Perfluorinated chemicals (PFCs are ubiquitously distributed in the environments including stainless pan-coating, raincoat, fire extinguisher, and semiconductor products. The PPAR family has been shown to contribute to the toxic effects of PFCs in thymus, immune and excretory systems. Herein, we demonstrated that perfluorooctanesulfonate (PFOS caused cell apoptosis through increasing ratio of Bcl-xS/xL, cytosolic cytochrome C, and caspase 3 activation in renal tubular cells (RTCs. In addition, PFOS increased transcription of inflammatory cytokines (i.e., TNFα, ICAM1, and MCP1 by NFκB activation. Conversely, PFOS reduced the mRNA levels of antioxidative enzymes, such as glutathione peroxidase, catalase, and superoxide dismutase, as a result of reduced PPARγ transactivational activity by using reporter and chromatin immuoprecipitation (ChIP assays. PFOS reduced the protein interaction between PPARγ and PPARγ coactivator-1 alpha (PGC1α by PPARγ deacetylation through Sirt1 upregulation, of which the binding of PPARγ and PGC1α to a peroxisome proliferator response element (PPRE in the promoter regions of these antioxidative enzymes was alleviated in the ChIP assay. Furthermore, Sirt1 also deacetylated p53 and then increased the binding of p53 to Bax, resulting in increased cytosolic cytochrome C. The effect of PPARγ inactivation by PFOS was validated using the PPARγ antagonist GW9662, whereas the adverse effects of PFOS were prevented by PPARγ overexpression and activators, rosiglitozone and L-carnitine, in RTCs. The in vitro finding of protective effect of L-carnitine was substantiated in vivo using Balb/c mice model subjected to PFOS challenge. Altogether, we provide in vivo and in vitro evidence for the protective mechanism of L-carnitine in eliminating PFOS-mediated renal injury, at least partially, through PPARγ activation.

  15. Glomerular and Tubular Damage Markers in Individuals with Progressive Albuminuria

    Science.gov (United States)

    Nauta, Ferdau L.; Scheven, Lieneke; Meijer, Esther; van Oeveren, Wim; de Jong, Paul E.; Bakker, Stephan J.L.

    2013-01-01

    Summary Background and objectives Albuminuria is associated with risk for renal and cardiovascular disease. It is difficult to predict which persons will progress in albuminuria. This study investigated whether assessment of urinary markers associated with damage to different parts of the nephron may help identify individuals that will progress in albuminuria. Design, setting, participants, & measurements Individuals were selected from a prospective community-based cohort study with serial follow-up and defined as “progressors” if they belonged to the quintile of participants with the most rapid annual increase in albuminuria, and reached an albuminuria ≥150 mg/d during follow-up. Patients with known renal disease or macroalbuminuria at baseline were excluded. Each progressor was matched to two control participants, based on baseline albuminuria, age, and sex. Furthermore, damage markers were measured in a separate set of healthy individuals. Results After a median follow-up of 8.6 years, 183 of 8394 participants met the criteria for progressive albuminuria. Baseline clinical characteristics were comparable between progressors and matched controls (n=366). Both had higher baseline albuminuria than the overall population. Urinary excretion of the glomerular damage marker IgG was significantly higher in progressors, whereas urinary excretion of proximal tubular damage markers and inflammatory markers was lower in these individuals compared with controls. Healthy individuals (n=109) had the lowest values for all urinary damage markers measured. Conclusions These data suggest that albuminuria associated with markers of glomerular damage is more likely to progress, whereas albuminuria associated with markers of tubulointerstitial damage is more likely to remain stable. PMID:23539232

  16. Human renal tubular epithelial cells suppress alloreactive T cell proliferation.

    Science.gov (United States)

    Demmers, M W H J; Korevaar, S S; Roemeling-van Rhijn, M; van den Bosch, T P P; Hoogduijn, M J; Betjes, M G H; Weimar, W; Baan, C C; Rowshani, A T

    2015-03-01

    Renal tubular epithelial cells (TECs) are one of the main targets of alloreactive T cells during acute rejection. We hypothesize that TECs modulate the outcome of alloimmunity by executing immunosuppressive effects in order to dampen the local inflammation. We studied whether TECs possess immunosuppressive capacities and if indoleamine 2,3-dioxygenase (IDO) might play a role in suppressing T cell alloreactivity. Next, we studied the role of programmed death ligand 1 (PD-L1) and intercellular adhesion molecule-1 (ICAM-1 with regard to TEC-related immunomodulatory effects. CD3/CD28 and alloactivated peripheral blood mononuclear cells were co-cultured with activated TECs. We analysed CD4(+) and CD8(+) T cell proliferation and apoptosis in the absence or presence of IDO inhibitor 1-methyl-L-tryptophan (1-L-MT), anti-PD-L1 and anti-ICAM-1. Further, we examined whether inhibition of T cell proliferation was cell-cell contact-dependent. We found that TECs dose-dependently inhibited CD4(+) and CD8(+) T cell proliferation (Pcell proliferation was only partially restored or failed to restore using 1-L-MT. Activated TECs increased early and late apoptosis of proliferating CD4(+) and CD8(+) T cells; only CD4(+) T cell apoptosis was statistically affected by 1-L-MT. Transwell experiments revealed that TEC-mediated immunosuppression is cell-cell contact-dependent. We found that anti-ICAM-1 affected only CD4(+) T cell apoptosis and not T cell proliferation. Our data show that TECs suppress both CD4(+) and CD8(+) T cell proliferation contact dependently. Interestingly, inhibition of proliferation and enhancement of apoptosis of T cell subsets is differentially regulated by indoleamine 2,3-dioxygenase and ICAM-1, with no evidence for the involvement of PD-L1 in our system. © 2014 British Society for Immunology.

  17. Design, construction and evaluation of solarized airlift tubular photobioreactor

    International Nuclear Information System (INIS)

    Bahadur, A; Zubair, M; Khan, M B

    2013-01-01

    An innovative photobioreactor is developed for growing algae in simulated conditions. The proposed design comprises of a continuous tubular irradiance loop and air induced liquid circulation with gas separation through air lift device. The unique features of air lift system are to ensure the shear free circulation of sensitive algal culture and induce light/dark cycles to the photosynthetic micro-organisms. The design strategy employs to model and construct a 20-liter laboratory scale unit using Boro-silicate glass tubing. The material is selected to ensure maximum photon transmission. All components of the device are designed to have flexibility to be replaced with an alternative design, providing fair chance of modification for future investigators. The principles of fluid mechanics are applied to describe geometrical attributes of the air lift system. Combination of LEDs and Florescent tube lights (Warm white) were used to illuminate the photosynthesis reaction area providing a possibility to control both illumination duration and light intensity. 200 Watt Solar PV system is designed to power up the device which included air pump (100 Watt) and illumination system (100 Watt). Algal strain Chlorella sp was inoculated in photobioreactor which was sparged with air and carbon dioxide. The growth was sustained in the batch mode with daily monitoring of temperature, pH and biomass concentration. The novel photobioreactor recorded a maximum experimental average yield of 0.65 g/l.day (11.3 g/m 2 .day) as compared to theoretical modeled yield of 0.82 g/l.day (14.26 g/m 2 .day), suggesting the device can be efficiently and cost-effectively employed in the production of algal biomass for biofuels, concomitantly mitigating CO 2 .

  18. Identification of genomic biomarkers for concurrent diagnosis of drug-induced renal tubular injury using a large-scale toxicogenomics database

    International Nuclear Information System (INIS)

    Kondo, Chiaki; Minowa, Yohsuke; Uehara, Takeki; Okuno, Yasushi; Nakatsu, Noriyuki; Ono, Atsushi; Maruyama, Toshiyuki; Kato, Ikuo; Yamate, Jyoji; Yamada, Hiroshi; Ohno, Yasuo; Urushidani, Tetsuro

    2009-01-01

    Drug-induced renal tubular injury is one of the major concerns in preclinical safety evaluations. Toxicogenomics is becoming a generally accepted approach for identifying chemicals with potential safety problems. In the present study, we analyzed 33 nephrotoxicants and 8 non-nephrotoxic hepatotoxicants to elucidate time- and dose-dependent global gene expression changes associated with proximal tubular toxicity. The compounds were administered orally or intravenously once daily to male Sprague-Dawley rats. The animals were exposed to four different doses of the compounds, and kidney tissues were collected on days 4, 8, 15, and 29. Gene expression profiles were generated from kidney RNA by using Affymetrix GeneChips and analyzed in conjunction with the histopathological changes. We used the filter-type gene selection algorithm based on t-statistics conjugated with the SVM classifier, and achieved a sensitivity of 90% with a selectivity of 90%. Then, 92 genes were extracted as the genomic biomarker candidates that were used to construct the classifier. The gene list contains well-known biomarkers, such as Kidney injury molecule 1, Ceruloplasmin, Clusterin, Tissue inhibitor of metallopeptidase 1, and also novel biomarker candidates. Most of the genes involved in tissue remodeling, the immune/inflammatory response, cell adhesion/proliferation/migration, and metabolism were predominantly up-regulated. Down-regulated genes participated in cell adhesion/proliferation/migration, membrane transport, and signal transduction. Our classifier has better prediction accuracy than any of the well-known biomarkers. Therefore, the toxicogenomics approach would be useful for concurrent diagnosis of renal tubular injury.

  19. Urinary excretion of beta 2-glycoprotein-1 (apolipoprotein H) and other markers of tubular malfunction in "non-tubular" renal disease.

    Science.gov (United States)

    Flynn, F V; Lapsley, M; Sansom, P A; Cohen, S L

    1992-07-01

    To determine whether urinary beta 2-glycoprotein-1 assays can provide improved discrimination between chronic renal diseases which are primarily of tubular or glomerular origin. Urinary beta 2-glycoprotein-1, retinol-binding protein, alpha 1-microglobulin, beta 2-microglobulin, N-acetyl-beta-D-glucosa-minidase and albumin were measured in 51 patients with primary glomerular disease, 23 with obstructive nephropathy, and 15 with polycystic kidney disease, and expressed per mmol of creatinine. Plasma beta 2-glycoprotein-1 was assayed in 52 patients and plasma creatinine in all 89. The findings were compared between the diagnostic groups and with previously published data relating to primary tubular disorders. All 31 patients with plasma creatinine greater than 200 mumol/l excreted increased amounts of beta 2-glycoprotein-1, retinol-binding protein, and alpha 1-microglobulin, and 29 had increased N-acetyl-beta-D-glucosaminidase; the quantities were generally similar to those found in comparable patients with primary tubular pathology. Among 58 with plasma creatinine concentrations under 200 mumol/l, increases in beta 2-glycoprotein-1, retinol-binding protein, and alpha 1-microglobulin excretion were less common and much smaller, especially in those with obstructive nephropathy and polycystic disease. The ratios of the excretion of albumin to the other proteins provided the clearest discrimination between the patients with glomerular or tubular malfunction, but an area of overlap was present which embraced those with obstructive nephropathy and polycystic disease. Increased excretion of beta 2-glycoprotein-1 due to a raised plasma concentration or diminution of tubular reabsorption, or both, is common in all the forms of renal disease investigated, and both plasma creatinine and urinary albumin must be taken into account when interpreting results. Ratios of urinary albumin: beta 2-glycoprotein-1 greater than 1000 are highly suggestive of primary glomerular disease and

  20. Plasmon induced modification of the transverse magneto-optical response in Fe antidot arrays

    Energy Technology Data Exchange (ETDEWEB)

    Torrado, J.F.; Armelles, G.; Garcia-Martin, A. [IMM - Instituto de Microelectronica de Madrid (CNM-CSIC), Isaac Newton 8, PTM, 28760 Tres Cantos, Madrid (Spain); Papaioannou, E.T. [Department of Physics and Astronomy, Uppsala University, 75121 Uppsala (Sweden); Ctistis, G. [Complex Photonic Systems (COPS), MESA+ Institute for Nanotechnology, University of Twente (Netherlands); Patoka, P.; Giersig, M. [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, 14109 Berlin (Germany)

    2010-10-15

    In this Letter we present the effects that the excitation of plasmon-like modes in periodically perforated Fe films have over the Transverse Magneto-Optical Kerr Effect (TMOKE). The excitation of the modes gives rise to clear signatures in the TMOKE spectra. We analyze the spectral position of the structures as a function of both the polar and azimuth angle. Schematic representation of the system, and TMOKE signal for a Fe membrane along {phi}=0 . (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  1. Single transverse spin asymmetry of forward neutrons

    International Nuclear Information System (INIS)

    Kopeliovich, B. Z.; Potashnikova, I. K.; Schmidt, Ivan; Soffer, J.

    2011-01-01

    We calculate the single transverse spin asymmetry A N (t), for inclusive neutron production in pp collisions at forward rapidities relative to the polarized proton in the energy range of RHIC. Absorptive corrections to the pion pole generate a relative phase between the spin-flip and nonflip amplitudes, leading to a transverse spin asymmetry which is found to be far too small to explain the magnitude of A N observed in the PHENIX experiment. A larger contribution, which does not vanish at high energies, comes from the interference of pion and a 1 -Reggeon exchanges. The unnatural parity of a 1 guarantees a substantial phase shift, although the magnitude is strongly suppressed by the smallness of diffractive πp→a 1 p cross section. We replace the Regge a 1 pole by the Regge cut corresponding to the πρ exchange in the 1 + S state. The production of such a state, which we treat as an effective pole a, forms a narrow peak in the 3π invariant mass distribution in diffractive πp interactions. The cross section is large, so one can assume that this state saturates the spectral function of the axial current and we can determine its coupling to nucleons via the partially conserved axial-vector-current constraint Goldberger-Treiman relation and the second Weinberg sum rule. The numerical results of the parameter-free calculation of A N are in excellent agreement with the PHENIX data.

  2. Transverse Field Effect in Fluxgate Sensors

    DEFF Research Database (Denmark)

    Brauer, Peter; Merayo, José M.G.; Nielsen, Otto V

    1997-01-01

    A model of the fluxgate magnetometer based on the field interactions in the fluxgate core has been derived. The non-linearity of the ringcore sensors due to large uncompensated fields transverse to the measuring axis are calculated and compared with measurements. Measurements of the non-linearity......A model of the fluxgate magnetometer based on the field interactions in the fluxgate core has been derived. The non-linearity of the ringcore sensors due to large uncompensated fields transverse to the measuring axis are calculated and compared with measurements. Measurements of the non......-linearity are made with a spectrum analyser, measuring the higher harmonics of an applied sinusoidal field. For a sensor with a permalloy ringcore of 1" in diameter the deviation from linearity is measured to about 15 nTp-p in the earth's field and the measurements are shown to fit well the calculations. Further......, the measurements and the calculations are also compared with a calibration model of the fluxgate sensor onboard the "MAGSAT" satellite. The later has a deviation from linearity of about 50 nTp-p but shows basically the same form of non-linearity as the measurements....

  3. Acoustic reflection log in transversely isotropic formations

    Science.gov (United States)

    Ronquillo Jarillo, G.; Markova, I.; Markov, M.

    2018-01-01

    We have calculated the waveforms of sonic reflection logging for a fluid-filled borehole located in a transversely isotropic rock. Calculations have been performed for an acoustic impulse source with the characteristic frequency of tens of kilohertz that is considerably less than the frequencies of acoustic borehole imaging tools. It is assumed that the borehole axis coincides with the axis of symmetry of the transversely isotropic rock. It was shown that the reflected wave was excited most efficiently at resonant frequencies. These frequencies are close to the frequencies of oscillations of a fluid column located in an absolutely rigid hollow cylinder. We have shown that the acoustic reverberation is controlled by the acoustic impedance of the rock Z = Vphρs for fixed parameters of the borehole fluid, where Vph is the velocity of horizontally propagating P-wave; ρs is the rock density. The methods of waveform processing to determine the parameters characterizing the reflected wave have been discussed.

  4. Importance of the hexagonal lipid phase in biological membrane organisation

    Directory of Open Access Journals (Sweden)

    Juliette eJouhet

    2013-12-01

    Full Text Available Abstract:Domains are present in every natural membrane. They are characterised by a distinctive protein and/or lipid composition. Their size is highly variable from the nano- to the micrometer scale. The domains confer specific properties to the membrane leading to original structure and function. The determinants leading to domain organisation are therefore important but remain obscure. This review presents how the ability of lipids to organize into hexagonal II or lamellar phases can promote particular local structures within membranes. Since biological membranes are composed of a mixture of lipids, each with distinctive biophysical properties, lateral and transversal sorting of lipids can promote creation of domains inside the membrane through local modulation of the lipid phase. Lipid biophysical properties have been characterized for long based on in vitro analyses using non-natural lipid molecules; their re-examinations using natural lipids might open interesting perspectives on membrane architecture occurring in vivo in various cellular and physiological contexts.

  5. Robotic transverse colectomy for mid-transverse colon cancer: surgical techniques and oncologic outcomes.

    Science.gov (United States)

    Jung, Kyung Uk; Park, Yoonah; Lee, Kang Young; Sohn, Seung-Kook

    2015-06-01

    Robot-assisted surgery for colon cancer has been reported in many studies, most of which worked on right and/or sigmoid colectomy. The aim of this study was to report our experience of robotic transverse colectomy with an intracorporeal anastomosis, provide details of the surgical technique, and present the theoretical benefits of the procedure. This is a retrospective review of prospectively collected data of robotic surgery for colorectal cancer performed by a single surgeon between May 2007 and February 2011. Out of 162 consecutive cases, we identified three robotic transverse colectomies, using a hand-sewn intracorporeal anastomosis. Two males and one female underwent transverse colectomies for malignant or premalignant disease. The mean docking time, time spent using the robot, and total operative time were 5, 268, and 307 min, respectively. There were no conversions to open or conventional laparoscopic technique. The mean length of specimen and number of lymph nodes retrieved were 14.1 cm and 6.7, respectively. One patient suffered from a wound seroma and recovered with conservative management. The mean hospital stay was 8.7 days. After a median follow-up of 72 months, there were no local or systemic recurrences. Robotic transverse colectomy seems to be a safe and feasible technique. It may minimize the necessity of mobilizing both colonic flexures, with facilitated intracorporeal hand-sewn anastomosis. However, further prospective studies with a larger number of patients are required to draw firm conclusions.

  6. Single transverse-spin asymmetry in high transverse momentum pion production in pp collisions

    DEFF Research Database (Denmark)

    Kouvaris, Christoforos; Qiu, Jian-Wei; Vogelsang, Werner

    2006-01-01

    We study the single-spin (left-right) asymmetry in single-inclusive pion production in hadronic scattering. This asymmetry is power-suppressed in the transverse momentum of the produced pion and can be analyzed in terms of twist-three parton correlation functions in the proton. We present new...

  7. Support and tool displacement device for the attachment of a tube bundle on a tubular plate of a steam generator

    International Nuclear Information System (INIS)

    Morisot, M.; Werle, R.; Michaud, J.P.

    1983-01-01

    The steam generator is being assembled, disposed with its axis horizontal and its tubular plate vertical; the device described in this patent, allows to automatize the preparation stages of the tubular plate and the attachment of the bundle, to shorten the construction of the steam generator and to remove drudgeries done by hand on the tubular plate or the tubes of the bundle. The invention can be applied to the construction of PWR steam generators [fr

  8. Cathepsin D protects renal tubular cells from damage induced by high glucose independent of its enzymatic activity

    OpenAIRE

    Du, Feng; Wang, Tian; Li, Si; Meng, Xin; Zhang, Hai-Yan; Li, De-Tian; Du, Zhen-Xian; Wang, Hua-Qin

    2017-01-01

    Although glomerular and vascular damage have been considered the main characteristics of diabetic kidney disease (DKD), accumulating data now indicate that tubular atrophy also plays a major role. Cathepsin D (CatD) is the major aspartate protease within lysosomes. The current study demonstrated that CatD expression was altered in the renal tubular epithelium in patients with diabetes mellitus (DM). In contrast to its low and uniform distribution in the tubular epithelium in normal kidney tis...

  9. Transversally enriched pipe element method (TEPEM): An effective numerical approach for blood flow modeling.

    Science.gov (United States)

    Mansilla Alvarez, Luis; Blanco, Pablo; Bulant, Carlos; Dari, Enzo; Veneziani, Alessandro; Feijóo, Raúl

    2017-04-01

    In this work, we present a novel approach tailored to approximate the Navier-Stokes equations to simulate fluid flow in three-dimensional tubular domains of arbitrary cross-sectional shape. The proposed methodology is aimed at filling the gap between (cheap) one-dimensional and (expensive) three-dimensional models, featuring descriptive capabilities comparable with the full and accurate 3D description of the problem at a low computational cost. In addition, this methodology can easily be tuned or even adapted to address local features demanding more accuracy. The numerical strategy employs finite (pipe-type) elements that take advantage of the pipe structure of the spatial domain under analysis. While low order approximation is used for the longitudinal description of the physical fields, transverse approximation is enriched using high order polynomials. Although our application of interest is computational hemodynamics and its relevance to pathological dynamics like atherosclerosis, the approach is quite general and can be applied in any internal fluid dynamics problem in pipe-like domains. Numerical examples covering academic cases as well as patient-specific coronary arterial geometries demonstrate the potentialities of the developed methodology and its performance when compared against traditional finite element methods. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  10. Mitochondrial dysfunction contributes to the cytotoxicity induced by tentacle extract from the jellyfish Cyanea capillata in rat renal tubular epithelial NRK-52E cells.

    Science.gov (United States)

    Wang, Tao; He, Qian; Xiao, Liang; Wang, Qianqian; Zhang, Bo; Wang, Beilei; Liu, Guoyan; Zheng, Jiemin; Yu, Bentong; Zhang, Liming

    2013-11-01

    Our previous studies have shown that tentacle extract (TE) from the jellyfish Cyanea capillata could induce a delayed jellyfish envenomation syndrome with severe multiple organ dysfunctions, among which renal injury with tubular necrosis seemed to be most serious. So, in this study, we aimed to explore the toxic effect of TE on rat renal tubular epithelial NRK-52E cells. Based on the previous findings that TE could cause oxidative damage in erythrocytes, the effects of TE on cell oxidative stress conditions, including ROS production and lipid peroxidation, and mitochondrial dysfunction associated with cell death were investigated in NRK-52E cells. The results showed that TE caused cell morphological change and decreased cell viability through induction of apoptosis and necrosis in NRK-52E cells. Meanwhile, ROS overproduction and mitochondrial membrane potential decrease were found before the cell death occurred. It was concluded that TE could induce cytotoxicity, especially apoptosis and necrosis, in NRK-52E cells, and mitochondrial dysfunction and ROS overproduction might play important roles in the process of cell injury and death. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Potentialities of a Membrane Reactor with Laccase Grafted Membranes for the Enzymatic Degradation of Phenolic Compounds in Water

    Directory of Open Access Journals (Sweden)

    Vorleak Chea

    2014-10-01

    Full Text Available This paper describes the degradation of phenolic compounds by laccases from Trametes versicolor in an enzymatic membrane reactor (EMR. The enzymatic membranes were prepared by grafting laccase on a gelatine layer previously deposited onto α-alumina tubular membranes. The 2,6-dimethoxyphenol (DMP was selected  from among the three different phenolic compounds tested (guaiacol, 4-chlorophenol and DMP to study the performance of the EMR in dead end configuration. At the lowest feed substrate concentration tested (100 mg·L−1, consumption increased with flux (up to 7.9 × 103 mg·h−1·m−2 at 128 L·h−1·m−2, whereas at the highest substrate concentration (500 mg·L−1, it was shown that the reaction was limited by the oxygen content.

  12. Osteomalacia complicating renal tubular acidosis in association with Sjogren's syndrome.

    Science.gov (United States)

    El Ati, Zohra; Fatma, Lilia Ben; Boulahya, Ghada; Rais, Lamia; Krid, Madiha; Smaoui, Wided; Maiz, Hedi Ben; Beji, Soumaya; Zouaghi, Karim; Moussa, Fatma Ben

    2014-09-01

    Renal involvement in Sjogren's syndrome (SS) is not uncommon and may precede other complaints. Tubulointerstitial nephritis is the most common renal disease in SS and may lead to renal tubular acidosis (RTA), which in turn may cause osteomalacia. Nevertheless, osteomalacia rarely occurs as the first manifestation of a renal tubule disorder due to SS. We herewith describe a 43-year-old woman who was admitted to our hospital for weakness, lumbago and inability to walk. X-ray of the long bones showed extensive demineralization of the bones. Laboratory investigations revealed chronic kidney disease with serum creatinine of 2.3 mg/dL and creatinine clearance of 40 mL/min, hypokalemia (3.2 mmol/L), hypophosphatemia (0.4 mmol/L), hypocalcemia (2.14 mmol/L) and hyperchloremic metabolic acidosis (chlorine: 114 mmol/L; alkaline reserve: 14 mmol/L). The serum alkaline phosphatase levels were elevated. The serum levels of 25-hydroxyvitamin D and 1,25-dihydroxy vitamin D were low and borderline low, respectively, and the parathyroid hormone level was 70 pg/L. Urinalysis showed inappropriate alkaline urine (urinary PH: 7), glycosuria with normal blood glucose, phosphaturia and uricosuria. These values indicated the presence of both distal and proximal RTA. Our patient reported dryness of the mouth and eyes and Schirmer's test showed xerophthalmia. An accessory salivary gland biopsy showed changes corresponding to stage IV of Chisholm and Masson score. Kidney biopsy showed diffuse and severe tubulo-interstitial nephritis with dense lymphoplasmocyte infiltrates. Sicca syndrome and renal interstitial infiltrates indicated SS as the underlying cause of the RTA and osteomalacia. The patient received alkalinization, vitamin D (Sterogyl ®), calcium supplements and steroids in an initial dose of 1 mg/kg/day, tapered to 10 mg daily. The prognosis was favorable and the serum creatinine level was 1.7 mg/dL, calcium was 2.2 mmol/L and serum phosphate was 0.9 mmol/L.

  13. Polydopamine-coated open tubular column for the separation of proteins by capillary electrochromatography.

    Science.gov (United States)

    Xiao, Xing; Wang, Wentao; Chen, Jia; Jia, Li

    2015-08-01

    The separation and determination of proteins in food is an important aspect in food industry. Inspired by the self-polymerization of dopamine under alkaline conditions and the natural adhesive properties of polydopamine, in this paper, a simple and economical method was developed for the preparation of polydopamine-coated open tubular column, in which ammonium persulfate was used as the source of oxygen to induce and facilitate the polymerization of dopamine to form polydopamine. In comparison with a naked fused-silica capillary, the direction and magnitude of the electro-osmotic flow of the as-prepared polydopamine-coated open tubular column could be manipulated by varying the pH values of background solutions due to the existence of amine and phenolic hydroxyl groups on polydopamine coating. The surface morphology of the polydopamine-coated open tubular column was studied by scanning electron microscopy, and the thickness of polydopamine coating was 106 nm. The performance of the polydopamine-coated open tubular column was validated by analysis of proteins. The relative standard deviations of migration times of proteins representing run-to-run, day-to-day, and column-to-column were less than 3.5%. In addition, the feasibility of the polydopamine-coated open tubular column for real samples was verified by the separation of proteins in chicken egg white and pure milk. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Transversal expansion study in the Landau hydrodynamic

    International Nuclear Information System (INIS)

    Pottag, F.W.

    1984-01-01

    The system of equations in the frame of Landau's hydrodynamical model for multiparticle production at high energies is studied. Taking as a first approximation the one-dimensional exact due to Khalatnikov, and a special set of curvilinear coordinates, the radial part is separated from the longitudinal one in the equations of motion, and a system of partial differential equations (non-linear, hyperbolic) is obtained for the radial part. These equations are solved numerically by the method of caracteristics. The hydrodynamical variables are obtained over all the three-dimensional-flow region as well as its variation with the mass of the initially expanding system. Both, the transverse rapidity distribution of the fluid and the inclusive particle distribution at 90 0 in the center of mass system, are calculated. The last one is compared with recent experimental data. (author) [pt

  15. Potentials for transverse trace-free tensors

    International Nuclear Information System (INIS)

    Conboye, Rory; Murchadha, Niall Ó

    2014-01-01

    In constructing and understanding initial conditions in the 3 + 1 formalism for numerical relativity, the transverse and trace-free (TT) part of the extrinsic curvature plays a key role. We know that TT tensors possess two degrees of freedom per space point. However, finding an expression for a TT tensor depending on only two scalar functions is a non-trivial task. Assuming either axial or translational symmetry, expressions depending on two scalar potentials alone are derived here for all TT tensors in flat 3-space. In a more general spatial slice, only one of these potentials is found, the same potential given in (Baker and Puzio 1999 Phys. Rev. D 59 044030) and (Dain 2001 Phys. Rev. D 64 124002), with the remaining equations reduced to a partial differential equation, depending on boundary conditions for a solution. As an exercise, we also derive the potentials which give the Bowen-York curvature tensor in flat space. (paper)

  16. Borel resummation of transverse momentum distributions

    CERN Document Server

    Bonvini, Marco; Ridolfi, Giovanni

    2009-01-01

    We present a new prescription for the resummation of contributions due to soft gluon emission to the trasverse momentum distribution of processes such as Drell-Yan production in hadronic collisions. We show that familiar difficulties in obtaining resummed results as a function of transverse momentum starting from impact-parameter space resummation are related to the divergence of the perturbative expansion of the momentum-space result. We construct a resummed expression by Borel resummation of this divergent series, removing the divergence in the Borel inversion through the inclusion of a suitable higher twist term. The ensuing resummation prescription is free of numerical instabilities, is stable upon the inclusion of subleading terms, and the original divergent perturbative series is asymptotic to it. We compare our results to those obtained using alternative prescriptions, and discuss the ambiguities related to the resummation procedure.

  17. PEP-II Transverse Feedback Electronics Upgrade

    International Nuclear Information System (INIS)

    Weber, J.; Chin, M.; Doolittle, L.; Akre, R.

    2005-01-01

    The PEP-II B Factory at the Stanford Linear Accelerator Center (SLAC) requires an upgrade of the transverse feedback system electronics. The new electronics require 12-bit resolution and a minimum sampling rate of 238 Msps. A Field Programmable Gate Array (FPGA) is used to implement the feedback algorithm. The FPGA also contains an embedded PowerPC 405 (PPC-405) processor to run control system interface software for data retrieval, diagnostics, and system monitoring. The design of this system is based on the Xilinx(R) ML300 Development Platform, a circuit board set containing an FPGA with an embedded processor, a large memory bank, and other peripherals. This paper discusses the design of a digital feedback system based on an FPGA with an embedded processor. Discussion will include specifications, component selection, and integration with the ML300 design

  18. The transverse damper system for RHIC

    International Nuclear Information System (INIS)

    Xu, J.; Claus, J.; Raka, E.; Ruggiero, A.G.; Shea, T.J.

    1991-01-01

    If the beam is injected with errors x c , x' c (or y c , y' c ) with respect to the closed orbit or disturbed by transverse instabilities, it will execute coherent oscillations and will be diluted in betatron phase space within a time interval of about 1/Δν turns, even if it is properly matched to the focusing characteristics of the lattice, unless there is an effective damper system to prevent this. Here Δν is the tune spread in the beam. Such a damper will not prevent dilution due to mismatches. Without such a damper the emittance of the beam will ultimately develop to a properly centered matched ellipse with an area ε in phase space that is larger than that of the injected one ε 0 which is also matched but off-centered by x c and x' c

  19. Transverse Momentum Correlations in Hadronic Z decays

    CERN Document Server

    Buskulic, Damir; Décamp, D; Ghez, P; Goy, C; Lees, J P; Lucotte, A; Minard, M N; Nief, J Y; Odier, P; Pietrzyk, B; Casado, M P; Chmeissani, M; Crespo, J M; Delfino, M C; Efthymiopoulos, I; Fernández, E; Fernández-Bosman, M; Garrido, L; Juste, A; Martínez, M; Orteu, S; Padilla, C; Park, I C; Pascual, A; Perlas, J A; Riu, I; Sánchez, F; Teubert, F; Colaleo, A; Creanza, D; De Palma, M; Gelao, G; Girone, M; Iaselli, Giuseppe; Maggi, G; Maggi, M; Marinelli, N; Nuzzo, S; Ranieri, A; Raso, G; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Tricomi, A; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Alemany, R; Bazarko, A O; Bonvicini, G; Bright-Thomas, P G; Cattaneo, M; Comas, P; Coyle, P; Drevermann, H; Forty, Roger W; Frank, M; Hagelberg, R; Harvey, J; Janot, P; Jost, B; Kneringer, E; Knobloch, J; Lehraus, Ivan; Lutters, G; Martin, E B; Mato, P; Minten, Adolf G; Miquel, R; Mir, L M; Moneta, L; Oest, T; Pacheco, A; Pusztaszeri, J F; Ranjard, F; Rensing, P E; Rizzo, G; Rolandi, Luigi; Schlatter, W D; Schmelling, M; Schmitt, M; Schneider, O; Tejessy, W; Tomalin, I R; Venturi, A; Wachsmuth, H W; Wagner, A; Ajaltouni, Ziad J; Barrès, A; Boyer, C; Falvard, A; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Perret, P; Podlyski, F; Proriol, J; Rosnet, P; Rossignol, J M; Fearnley, Tom; Hansen, J B; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Rensch, B; Wäänänen, A; Kyriakis, A; Markou, C; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Zachariadou, K; Blondel, A; Bonneaud, G R; Brient, J C; Bourdon, P; Rougé, A; Rumpf, M; Valassi, Andrea; Verderi, M; Videau, H L; Candlin, D J; Parsons, M I; Focardi, E; Parrini, G; Corden, M; Georgiopoulos, C H; Jaffe, D E; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Casper, David William; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Passalacqua, L; Pepé-Altarelli, M; Curtis, L; Dorris, S J; Halley, A W; Knowles, I G; Lynch, J G; O'Shea, V; Raine, C; Reeves, P; Scarr, J M; Smith, K; Teixeira-Dias, P; Thompson, A S; Thomson, F; Thorn, S; Turnbull, R M; Becker, U; Geweniger, C; Graefe, G; Hanke, P; Hansper, G; Hepp, V; Kluge, E E; Putzer, A; Schmidt, M; Sommer, J; Tittel, K; Werner, S; Wunsch, M; Abbaneo, D; Beuselinck, R; Binnie, David M; Cameron, W; Dornan, Peter J; Moutoussi, A; Nash, J; Sedgbeer, J K; Stacey, A M; Williams, M D; Dissertori, G; Girtler, P; Kuhn, D; Rudolph, G; Betteridge, A P; Bowdery, C K; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Sloan, Terence; Williams, M I; Galla, A; Giehl, I; Greene, A M; Hoffmann, C; Jakobs, K; Kleinknecht, K; Quast, G; Renk, B; Rohne, E; Sander, H G; Van Gemmeren, P; Zeitnitz, C; Aubert, Jean-Jacques; Bencheikh, A M; Benchouk, C; Bonissent, A; Bujosa, G; Calvet, D; Carr, J; Diaconu, C A; Etienne, F; Konstantinidis, N P; Payre, P; Rousseau, D; Talby, M; Sadouki, A; Thulasidas, M; Trabelsi, K; Aleppo, M; Ragusa, F; Bauer, C; Berlich, R; Blum, Walter; Büscher, V; Dietl, H; Dydak, Friedrich; Ganis, G; Gotzhein, C; Kroha, H; Lütjens, G; Lutz, Gerhard; Männer, W; Moser, H G; Richter, R H; Rosado-Schlosser, A; Schael, S; Settles, Ronald; Seywerd, H C J; Saint-Denis, R; Wiedenmann, W; Wolf, G; Boucrot, J; Callot, O; Choi, Y; Cordier, A; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Höcker, A; Jacholkowska, A; Jacquet, M; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Nikolic, I A; Park, H J; Schune, M H; Simion, S; Veillet, J J; Videau, I; Zerwas, D; Azzurri, P; Bagliesi, G; Batignani, G; Bettarini, S; Bozzi, C; Calderini, G; Carpinelli, M; Ciocci, M A; Ciulli, V; Dell'Orso, R; Fantechi, R; Ferrante, I; Foà, L; Forti, F; Giassi, A; Giorgi, M A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Palla, Fabrizio; Sanguinetti, G; Sciabà, A; Spagnolo, P; Steinberger, Jack; Tenchini, Roberto; Tonelli, G; Vannini, C; Verdini, P G; Walsh, J; Blair, G A; Bryant, L M; Cerutti, F; Chambers, J T; Gao, Y; Green, M G; Medcalf, T; Perrodo, P; Strong, J A; Von Wimmersperg-Töller, J H; Botterill, David R; Clifft, R W; Edgecock, T R; Haywood, S; Maley, P; Norton, P R; Thompson, J C; Wright, A E; Bloch-Devaux, B; Colas, P; Emery, S; Kozanecki, Witold; Lançon, E; Lemaire, M C; Locci, E; Marx, B; Pérez, P; Rander, J; Renardy, J F; Roussarie, A; Schuller, J P; Schwindling, J; Trabelsi, A; Vallage, B; Black, S N; Dann, J H; Johnson, R P; Kim, H Y; Litke, A M; McNeil, M A; Taylor, G; Booth, C N; Boswell, R; Brew, C A J; Cartwright, S L; Combley, F; Köksal, A; Lehto, M H; Newton, W M; Reeve, J; Thompson, L F; Böhrer, A; Brandt, S; Cowan, G D; Grupen, Claus; Minguet-Rodríguez, J A; Rivera, F; Saraiva, P; Smolik, L; Stephan, F; Apollonio, M; Bosisio, L; Della Marina, R; Giannini, G; Gobbo, B; Musolino, G; Rothberg, J E; Wasserbaech, S R; Armstrong, S R; Elmer, P; Feng, Z; Ferguson, D P S; Gao, Y S; González, S; Grahl, J; Greening, T C; Hayes, O J; Hu, H; McNamara, P A; Nachtman, J M; Orejudos, W; Pan, Y B; Saadi, Y; Scott, I J; Walsh, A M; Wu Sau Lan; Wu, X; Yamartino, J M; Zheng, M; Zobernig, G

    1997-01-01

    Using data obtained with the ALEPH detector at the Z resonance, a measure based on transverse momentum is shown to exhibit a correlation between the two halves of a hadronic event which cannot be explained by energy-momentum conservation, flavour conservation, the imposition of an event axis or imperfect event reconstruction. Two possible explanations based on Monte Carlo models are examined: a) ARIADNE, with the correlation forming early in the parton shower and with the transition from partons to hadrons playing only a minor part; b) JETSET, with the correlation forming at the fragmentation stage. A correlation technique based on a jet cluster analysis is used to make a comparison of the models with the data. It is concluded that both non-perturbative and perturbative effects make important contributions to the observed correlation.

  20. A tilted transversely isotropic slowness surface approximation

    KAUST Repository

    Stovas, A.

    2012-05-09

    The relation between vertical and horizontal slownesses, better known as the dispersion relation, for transversely isotropic media with a tilted symmetry axis (TTI) requires solving a quartic polynomial equation, which does not admit a practical explicit solution to be used, for example, in downward continuation. Using a combination of the perturbation theory with respect to the anelliptic parameter and Shanks transform to improve the accuracy of the expansion, we develop an explicit formula for the vertical slowness that is highly accurate for all practical purposes. It also reveals some insights into the anisotropy parameter dependency of the dispersion relation including the low impact that the anelliptic parameter has on the vertical placement of reflectors for a small tilt in the symmetry angle. © 2012 European Association of Geoscientists & Engineers.