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Sample records for membrane compartments enriched

  1. Membrane order in the plasma membrane and endocytic recycling compartment.

    Science.gov (United States)

    Iaea, David B; Maxfield, Frederick R

    2017-01-01

    The cholesterol content of membranes plays an important role in organizing membranes for signal transduction and protein trafficking as well as in modulating the biophysical properties of membranes. While the properties of model or isolated membranes have been extensively studied, there has been little evaluation of internal membranes in living cells. Here, we use a Nile Red based probe, NR12S, and ratiometric live cell imaging, to analyze the membrane order of the plasma membrane and endocytic recycling compartment. We find that after a brief incubation to allow endocytosis, NR12S is distributed between the plasma membrane and the endocytic recycling compartment. The NR12S reports that the endocytic recycling compartment is more highly ordered than the plasma membrane. We also find that the plasma membrane and the endocytic recycling compartment are differentially affected by altering cellular cholesterol levels. The membrane order of the plasma membrane, but not the endocytic recycling compartment, is altered significantly when cellular cholesterol content is increased or decreased by 20%. These results demonstrate that changes in cellular cholesterol differentially alter membrane order within different organelles.

  2. Membrane compartment of Can1 (MCC): specialized functional microdomain of the yeast plasma membrane

    OpenAIRE

    Doudová, Lenka

    2017-01-01

    Membrane compartment of Can1 (MCC): specialized functional microdomain of the yeast plasma membrane Yeast plasma membrane is divided into several different compartments. Membrane compartment of Can1 is specific for its protein and lipid composition, furthermore it creates furrow-like invaginations on the plasma membrane. These invaginations are made by multiprotein complexes called eisosomes, which are located in the cytosolic side of MCCs. It was established that this domain plays an importa...

  3. The subapical compartment : a traffic center in membrane polarity development

    NARCIS (Netherlands)

    Hoekstra, D; Tyteca, D; van IJzendoorn, SCD

    2004-01-01

    Spatially separated apical and basolateral plasma membrane domains that have distinct functions and molecular compositions are a characteristic feature of epithelial cell polarity. The subapical compartment (SAC), also known as the common endosome (CE), where endocytic pathways from both surfaces

  4. The formation of endosymbiotic membrane compartments: membrane identity markers and the regulation of vesicle trafficking

    NARCIS (Netherlands)

    Ivanov, S.

    2012-01-01

    In symbiosis of plants and arbuscular mycorrhizal fungi as well as in rhizobium-legume symbiosis the microbes are hosted intracellularly, inside specialized membrane compartments of the host. These membrane compartments are morphologically different but similar in function, since they control

  5. Enrichment of Phosphatidylethanolamine in Viral Replication Compartments via Co-opting the Endosomal Rab5 Small GTPase by a Positive-Strand RNA Virus.

    Directory of Open Access Journals (Sweden)

    Kai Xu

    2016-10-01

    Full Text Available Positive-strand RNA viruses build extensive membranous replication compartments to support replication and protect the virus from antiviral responses by the host. These viruses require host factors and various lipids to form viral replication complexes (VRCs. The VRCs built by Tomato bushy stunt virus (TBSV are enriched with phosphatidylethanolamine (PE through a previously unknown pathway. To unravel the mechanism of PE enrichment within the TBSV replication compartment, in this paper, the authors demonstrate that TBSV co-opts the guanosine triphosphate (GTP-bound active form of the endosomal Rab5 small GTPase via direct interaction with the viral replication protein. Deletion of Rab5 orthologs in a yeast model host or expression of dominant negative mutants of plant Rab5 greatly decreases TBSV replication and prevents the redistribution of PE to the sites of viral replication. We also show that enrichment of PE in the viral replication compartment is assisted by actin filaments. Interestingly, the closely related Carnation Italian ringspot virus, which replicates on the boundary membrane of mitochondria, uses a similar strategy to the peroxisomal TBSV to hijack the Rab5-positive endosomes into the viral replication compartments. Altogether, usurping the GTP-Rab5-positive endosomes allows TBSV to build a PE-enriched viral replication compartment, which is needed to support peak-level replication. Thus, the Rab family of small GTPases includes critical host factors assisting VRC assembly and genesis of the viral replication compartment.

  6. COMPARTMENTS

    DEFF Research Database (Denmark)

    Binder, Janos X; Pletscher-Frankild, Sune; Tsafou, Kalliopi

    2014-01-01

    of the localization of a protein, it is thus necessary to consult multiple databases and prediction tools. To address this, we present the COMPARTMENTS resource, which integrates all sources listed above as well as the results of automatic text mining. The resource is automatically kept up to date with source...

  7. Novel Membranes and Processes for Oxygen Enrichment

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Haiqing

    2011-11-15

    The overall goal of this project is to develop a membrane process that produces air containing 25-35% oxygen, at a cost of $25-40/ton of equivalent pure oxygen (EPO2). Oxygen-enriched air at such a low cost will allow existing air-fueled furnaces to be converted economically to oxygen-enriched furnaces, which in turn will improve the economic and energy efficiency of combustion processes significantly, and reduce the cost of CO{sub 2} capture and sequestration from flue gases throughout the U.S. manufacturing industries. During the 12-month Concept Definition project: We identified a series of perfluoropolymers (PFPs) with promising oxygen/nitrogen separation properties, which were successfully made into thin film composite membranes. The membranes showed oxygen permeance as high as 1,200 gpu and oxygen/nitrogen selectivity of 3.0, and the permeance and selectivity were stable over the time period tested (60 days). We successfully scaled up the production of high-flux PFP-based membranes, using MTR's commercial coaters. Two bench-scale spiral-wound modules with countercurrent designs were made and parametric tests were performed to understand the effect of feed flow rate and pressure, permeate pressure and sweep flow rate on the membrane module separation properties. At various operating conditions that modeled potential industrial operating conditions, the module separation properties were similar to the pure-gas separation properties in the membrane stamps. We also identified and synthesized new polymers [including polymers of intrinsic microporosity (PIMs) and polyimides] with higher oxygen/nitrogen selectivity (3.5-5.0) than the PFPs, and made these polymers into thin film composite membranes. However, these membranes were susceptible to severe aging; pure-gas permeance decreased nearly six-fold within two weeks, making them impractical for industrial applications of oxygen enrichment. We tested the effect of oxygen-enriched air on NO{sub x} emissions

  8. GSL-enriched membrane microdomains in innate immune responses.

    Science.gov (United States)

    Nakayama, Hitoshi; Ogawa, Hideoki; Takamori, Kenji; Iwabuchi, Kazuhisa

    2013-06-01

    Many pathogens target glycosphingolipids (GSLs), which, together with cholesterol, GPI-anchored proteins, and various signaling molecules, cluster on host cell membranes to form GSL-enriched membrane microdomains (lipid rafts). These GSL-enriched membrane microdomains may therefore be involved in host-pathogen interactions. Innate immune responses are triggered by the association of pathogens with phagocytes, such as neutrophils, macrophages and dendritic cells. Phagocytes express a diverse array of pattern-recognition receptors (PRRs), which sense invading microorganisms and trigger pathogen-specific signaling. PRRs can recognize highly conserved pathogen-associated molecular patterns expressed on microorganisms. The GSL lactosylceramide (LacCer, CDw17), which binds to various microorganisms, including Candida albicans, is expressed predominantly on the plasma membranes of human mature neutrophils and forms membrane microdomains together with the Src family tyrosine kinase Lyn. These LacCer-enriched membrane microdomains can mediate superoxide generation, migration, and phagocytosis, indicating that LacCer functions as a PRR in innate immunity. Moreover, the interactions of GSL-enriched membrane microdomains with membrane proteins, such as growth factor receptors, are important in mediating the physiological properties of these proteins. Similarly, we recently found that interactions between LacCer-enriched membrane microdomains and CD11b/CD18 (Mac-1, CR3, or αMβ2-integrin) are significant for neutrophil phagocytosis of non-opsonized microorganisms. This review describes the functional role of LacCer-enriched membrane microdomains and their interactions with CD11b/CD18.

  9. Effect of heterogeneity on the characterization of cell membrane compartments: I. Uniform size and permeability.

    Science.gov (United States)

    Hall, Damien

    2010-03-15

    Observations of the motion of individual molecules in the membrane of a number of different cell types have led to the suggestion that the outer membrane of many eukaryotic cells may be effectively partitioned into microdomains. A major cause of this suggested partitioning is believed to be due to the direct/indirect association of the cytosolic face of the cell membrane with the cortical cytoskeleton. Such intimate association is thought to introduce effective hydrodynamic barriers into the membrane that are capable of frustrating molecular Brownian motion over distance scales greater than the average size of the compartment. To date, the standard analytical method for deducing compartment characteristics has relied on observing the random walk behavior of a labeled lipid or protein at various temporal frequencies and different total lengths of time. Simple theoretical arguments suggest that the presence of restrictive barriers imparts a characteristic turnover to a plot of mean squared displacement versus sampling period that can be interpreted to yield the average dimensions of the compartment expressed as the respective side lengths of a rectangle. In the following series of articles, we used computer simulation methods to investigate how well the conventional analytical strategy coped with heterogeneity in size, shape, and barrier permeability of the cell membrane compartments. We also explored questions relating to the necessary extent of sampling required (with regard to both the recorded time of a single trajectory and the number of trajectories included in the measurement bin) for faithful representation of the actual distribution of compartment sizes found using the SPT technique. In the current investigation, we turned our attention to the analytical characterization of diffusion through cell membrane compartments having both a uniform size and permeability. For this ideal case, we found that (i) an optimum sampling time interval existed for the analysis

  10. Myosin-Powered Membrane Compartment Drives Cytoplasmic Streaming, Cell Expansion and Plant Development.

    Science.gov (United States)

    Peremyslov, Valera V; Cole, Rex A; Fowler, John E; Dolja, Valerian V

    2015-01-01

    Using genetic approaches, particle image velocimetry and an inert tracer of cytoplasmic streaming, we have made a mechanistic connection between the motor proteins (myosins XI), cargo transported by these motors (distinct endomembrane compartment defined by membrane-anchored MyoB receptors) and the process of cytoplasmic streaming in plant cells. It is shown that the MyoB compartment in Nicotiana benthamiana is highly dynamic moving with the mean velocity of ~3 μm/sec. In contrast, Golgi, mitochondria, peroxisomes, carrier vesicles and a cytosol flow tracer share distinct velocity profile with mean velocities of 0.6-1.5 μm/sec. Dominant negative inhibition of the myosins XI or MyoB receptors using overexpression of the N. benthamiana myosin cargo-binding domain or MyoB myosin-binding domain, respectively, resulted in velocity reduction for not only the MyoB compartment, but also each of the tested organelles, vesicles and cytoplasmic streaming. Furthermore, the extents of this reduction were similar for each of these compartments suggesting that MyoB compartment plays primary role in cytosol dynamics. Using gene knockout analysis in Arabidopsis thaliana, it is demonstrated that inactivation of MyoB1-4 results in reduced velocity of mitochondria implying slower cytoplasmic streaming. It is also shown that myosins XI and MyoB receptors genetically interact to contribute to cell expansion, plant growth, morphogenesis and proper onset of flowering. These results support a model according to which myosin-dependent, MyoB receptor-mediated transport of a specialized membrane compartment that is conserved in all land plants drives cytoplasmic streaming that carries organelles and vesicles and facilitates cell growth and plant development.

  11. Experimental Validation of a Permeability Model for Enrichment Membranes

    International Nuclear Information System (INIS)

    Orellano, Pablo; Brasnarof, Daniel; Florido Pablo

    2003-01-01

    An experimental loop with a real scale diffuser, in a single enrichment-stage configuration, was operated with air at different process conditions, in order to characterize the membrane permeability.Using these experimental data, an analytical geometric-and-morphologic-based model was validated.It is conclude that a new set of independent measurements, i.e. enrichment, is necessary in order to fully characterize diffusers, because of its internal parameters are not univocally determinated with permeability experimental data only

  12. Recognition of GPCRs by peptide ligands and membrane compartments theory: structural studies of endogenous peptide hormones in membrane environment.

    Science.gov (United States)

    Sankararamakrishnan, Ramasubbu

    2006-04-01

    One of the largest family of cell surface proteins, G-protein coupled receptors (GPCRs) regulate virtually all known physiological processes in mammals. With seven transmembrane segments, they respond to diverse range of extracellular stimuli and represent a major class of drug targets. Peptidergic GPCRs use endogenous peptides as ligands. To understand the mechanism of GPCR activation and rational drug design, knowledge of three-dimensional structure of receptor-ligand complex is important. The endogenous peptide hormones are often short, flexible and completely disordered in aqueous solution. According to "Membrane Compartments Theory", the flexible peptide binds to the membrane in the first step before it recognizes its receptor and the membrane-induced conformation is postulated to bind to the receptor in the second step. Structures of several peptide hormones have been determined in membrane-mimetic medium. In these studies, micelles, reverse micelles and bicelles have been used to mimic the cell membrane environment. Recently, conformations of two peptide hormones have also been studied in receptor-bound form. Membrane environment induces stable secondary structures in flexible peptide ligands and membrane-induced peptide structures have been correlated with their bioactivity. Results of site-directed mutagenesis, spectroscopy and other experimental studies along with the conformations determined in membrane medium have been used to interpret the role of individual residues in the peptide ligand. Structural differences of membrane-bound peptides that belong to the same family but differ in selectivity are likely to explain the mechanism of receptor selectivity and specificity of the ligands. Knowledge of peptide 3D structures in membrane environment has potential applications in rational drug design.

  13. Review of Membrane Oxygen Enrichment for Efficient Combustion

    Science.gov (United States)

    Ariono, Danu; Kusuma Wardani, Anita

    2017-07-01

    Oxygen enrichment from air is a simple way of increasing the efficiency of combustion process, as in oxy-combustion. Oxy-combustion has become one of the most attracting combustion technologies because of its potential to address both pollutant reduction and CO2 capture. In oxy-combustion, the fuel and recycled flue gas are combusted with oxygen enriched air (OEA). By using OEA, many benefits can be obtained, such as increasing available heat, improving ignition characteristics, flue gas reduction, increasing productivity, energy efficiency, turndown ratio, and flame stability. Membrane-based gas separation for OEA production becomes an attractive technology over the conventional technology due to the some advantages, including low capital cost, low energy consumption, compact size, and modularity. A single pass through membrane usually can enrich O2 concentration in the air up to 35% and a 50% concentration can be achieved with a double pass of membrane. The use of OEA in the combustion process eliminates the presence of nitrogen in the flue gas. Hence, the flue gas is mainly composed of CO2 and condensable water that can be easily separated. This paper gives an overview of oxy-combustion with membrane technology for oxygen enrichment process. Special attention is given to OEA production and the effect of OEA to the efficiency of combustion.

  14. Morphological and biochemical characterization of the membranous hepatitis C virus replication compartment.

    Science.gov (United States)

    Paul, David; Hoppe, Simone; Saher, Gesine; Krijnse-Locker, Jacomine; Bartenschlager, Ralf

    2013-10-01

    Like all other positive-strand RNA viruses, hepatitis C virus (HCV) induces rearrangements of intracellular membranes that are thought to serve as a scaffold for the assembly of the viral replicase machinery. The most prominent membranous structures present in HCV-infected cells are double-membrane vesicles (DMVs). However, their composition and role in the HCV replication cycle are poorly understood. To gain further insights into the biochemcial properties of HCV-induced membrane alterations, we generated a functional replicon containing a hemagglutinin (HA) affinity tag in nonstructural protein 4B (NS4B), the supposed scaffold protein of the viral replication complex. By using HA-specific affinity purification we isolated NS4B-containing membranes from stable replicon cells. Complementing biochemical and electron microscopy analyses of purified membranes revealed predominantly DMVs, which contained viral proteins NS3 and NS5A as well as enzymatically active viral replicase capable of de novo synthesis of HCV RNA. In addition to viral factors, co-opted cellular proteins, such as vesicle-associated membrane protein-associated protein A (VAP-A) and VAP-B, that are crucial for viral RNA replication, as well as cholesterol, a major structural lipid of detergent-resistant membranes, are highly enriched in DMVs. Here we describe the first isolation and biochemical characterization of HCV-induced DMVs. The results obtained underline their central role in the HCV replication cycle and suggest that DMVs are sites of viral RNA replication. The experimental approach described here is a powerful tool to more precisely define the molecular composition of membranous replication factories induced by other positive-strand RNA viruses, such as picorna-, arteri- and coronaviruses.

  15. Oxygen enriched air using membrane for palm oil wastewater treatment

    Directory of Open Access Journals (Sweden)

    Ramlah Mohd Tajuddin

    2002-11-01

    Full Text Available A research aimed to explore new method of aeration using oxygen enriched air performance on BOD reduction of palm oil wastewater was conducted. The oxygen enriched air was obtained from an Oxygen Enriched System (OES developed using asymmetric polysulfone hollow fiber membrane with composition consisting of PSF: 22%, DMAc: 31.8%, THF: 31.8%, EtOH: 14.4%. Palm oil wastewater samples were taken from facultative pond effluent. These samples were tested for its initial biochemical oxygen demand (BOD, total suspended solids (TSS, pH, conductivity, turbidity, dissolved oxygen (DO, suspended solids (SS, and total dissolved solids (TDS before being subjected to two modes of aeration system, that is diffused air and oxygen enriched air. These water quality concentrations were tested for every 20 minutes for two-hour period during the aeration process. Results of BOD, TSS, pH, conductivity, DO, SS and TDS concentrations against time of samples from the two modes of aeration were then compared. It was found that DO concentration achieved in oxygen enriched air aeration was better than aeration using diffused air system. Aeration using OES improve the DO concentration in the wastewater and thus improve the BOD reduction and also influence other physical characteristics of wastewater. This phenomenon indicates the advantage of using air with higher oxygen concentration for wastewater aeration instead of diffused air system.

  16. Annexins as organizers of cholesterol- and sphingomyelin-enriched membrane microdomains in Niemann-Pick type C disease.

    Science.gov (United States)

    Domon, Magdalena; Nasir, Mehmet Nail; Matar, Gladys; Pikula, Slawomir; Besson, Françoise; Bandorowicz-Pikula, Joanna

    2012-06-01

    Growing evidence suggests that membrane microdomains enriched in cholesterol and sphingomyelin are sites for numerous cellular processes, including signaling, vesicular transport, interaction with pathogens, and viral infection, etc. Recently some members of the annexin family of conserved calcium and membrane-binding proteins have been recognized as cholesterol-interacting molecules and suggested to play a role in the formation, stabilization, and dynamics of membrane microdomains to affect membrane lateral organization and to attract other proteins and signaling molecules onto their territory. Furthermore, annexins were implicated in the interactions between cytosolic and membrane molecules, in the turnover and storage of cholesterol and in various signaling pathways. In this review, we focus on the mechanisms of interaction of annexins with lipid microdomains and the role of annexins in membrane microdomains dynamics including possible participation of the domain-associated forms of annexins in the etiology of human lysosomal storage disease called Niemann-Pick type C disease, related to the abnormal storage of cholesterol in the lysosome-like intracellular compartment. The involvement of annexins and cholesterol/sphingomyelin-enriched membrane microdomains in other pathologies including cardiac dysfunctions, neurodegenerative diseases, obesity, diabetes mellitus, and cancer is likely, but is not supported by substantial experimental observations, and therefore awaits further clarification.

  17. Primary study of ethyl cellulose nanofiber for oxygen-enrichment membrane

    Directory of Open Access Journals (Sweden)

    Shen Jing

    2016-01-01

    Full Text Available Ethyl cellulose is widely used for oxygen-enrichment membrane, however, its nanofiber membrane was rarely developed though it behaves more excellent performance. This paper gives a preliminary study to produce oxygen-enrichment membrane by bubbfil spinning.

  18. Porphyromonas gingivalis Outer Membrane Vesicles Enter Human Epithelial Cells via an Endocytic Pathway and Are Sorted to Lysosomal Compartments

    Science.gov (United States)

    Furuta, Nobumichi; Tsuda, Kayoko; Omori, Hiroko; Yoshimori, Tamotsu; Yoshimura, Fuminobu; Amano, Atsuo

    2009-01-01

    Porphyromonas gingivalis, a periodontal pathogen, secretes outer membrane vesicles (MVs) that contain major virulence factors, including major fimbriae and proteases termed gingipains, although it is not confirmed whether MVs enter host cells. In this study, we analyzed the mechanisms involved in the interactions of P. gingivalis MVs with human epithelial cells. Our results showed that MVs swiftly adhered to HeLa and immortalized human gingival epithelial cells in a fimbria-dependent manner and then entered via a lipid raft-dependent endocytic pathway. The intracellular MVs were subsequently routed to early endosome antigen 1-associated compartments and then were sorted to lysosomal compartments within 90 min, suggesting that intracellular MVs were ultimately degraded by the cellular digestive machinery. However, P. gingivalis MVs remained there for over 24 h and significantly induced acidified compartment formation after being taken up by the cellular digestive machinery. In addition, MV entry was shown to be mediated by a novel pathway for transmission of bacterial products into host cells, a Rac1-regulated pinocytic pathway that is independent of caveolin, dynamin, and clathrin. Our findings indicate that P. gingivalis MVs efficiently enter host cells via an endocytic pathway and survive within the endocyte organelles for an extended period, which provides better understanding of the role of MVs in the etiology of periodontitis. PMID:19651865

  19. Cascades for natural water enrichment in deuterium and oxygen-18 using membrane permeation

    International Nuclear Information System (INIS)

    Chmielewski, A.G.; Matuszak, A.; Zakrzewska-Trznadel, G.; Van Hook, A.

    1991-01-01

    The enrichment of water in heavy isotopes by permeation through a hydrophobic membrane is described. Simple counter - current cascades are of no practical interest because of their high energy demand. A better solution is to employ a double counter - current cascade re-utilizing part of the heat of condensation. Currently employed methods of natural water enrichment in heavy isotopes are compared to the proposed membrane process. (author). 18 refs, 14 tabs, 21 figs

  20. Free Flow Zonal Electrophoresis for Fractionation of Plant Membrane Compartments Prior to Proteomic Analysis.

    Science.gov (United States)

    Barkla, Bronwyn J

    2018-01-01

    Free flow zonal electrophoresis (FFZE) is a versatile, reproducible, and potentially high-throughput technique for the separation of plant organelles and membranes by differences in membrane surface charge. It offers considerable benefits over traditional fractionation techniques, such as density gradient centrifugation and two-phase partitioning, as it is relatively fast, sample recovery is high, and the method provides unparalleled sample purity. It has been used to successfully purify chloroplasts and mitochondria from plants but also, to obtain highly pure fractions of plasma membrane, tonoplast, ER, Golgi, and thylakoid membranes. Application of the technique can significantly improve protein coverage in large-scale proteomics studies by decreasing sample complexity. Here, we describe the method for the fractionation of plant cellular membranes from leaves by FFZE.

  1. Membrane-bound organelles versus membrane-less compartments and their control of anabolic pathways in Drosophila

    NARCIS (Netherlands)

    Aguilera-Gomez, Angelica; Rabouille, Catherine

    2017-01-01

    Classically, we think of cell compartmentalization as being achieved by membrane-bound organelles. It has nevertheless emerged that membrane-less assemblies also largely contribute to this compartmentalization. Here, we compare the characteristics of both types of compartmentalization in term of

  2. Characterization and quantitation of concanavalin A binding by plasma membrane enriched fractions from soybean root

    International Nuclear Information System (INIS)

    Berkowitz, R.L.; Travis, R.L.

    1981-01-01

    The binding of concanavalin A (Con A) to soybean root membranes in plasma membrane enriched fractions (recovered from the 34/45% interface of simplified discontinuous sucrose density gradients) was studied using a radiochemical assay employing tritated ( 3 H)-Con A. The effect of lectin concentration, time, and membrane protein concentration on the specific binding of 3 H-Con A by the membranes was evaluated. Kinetic analyses showed that Con A will react with membranes in that fraction in a characteristic and predictable manner. The parameters for an optimal and standard binding assay were established. Maximal binding occurred with Con A concentrations in the range of 8 to 16% of the total membrane protein with incubation times greater than 40 min at 22 C. Approximately 10 15 molecules of 3 H-Con A were bound per microgram of membrane protein at saturation. Binding was reversible. Greater than 92% of the total Con A bound at saturation was released by addition of α-methyl mannoside. A major peak of 3 H-Con A binding was also observed in fractions recovered from the 25/30% interface of a complex discontinuous sucrose density gradient when membranes were isolated in the absence of Mg 2+ . When high Mg 2+ was present in the isolation and gradient media, the peak was shifted to a fraction recovered from the 34/38% sucrose interface. These results suggest that Con A binding sites are also present on membranes of the endoplasmic reticulum. The amount of Con A bound by endoplasmic reticulum membranes was at least twice the amount bound by membranes in plasma membrane enriched fractions when binding was compared on a per unit membrane protein basis. In contrast, mitochondrial inner membranes, which equilibrate at the same density as plasma membranes, had little ability to bind the lectin

  3. Separation of gases through gas enrichment membrane composites

    Science.gov (United States)

    Swedo, Raymond J.; Kurek, Paul R.

    1988-01-01

    Thin film composite membranes having as a permselective layer a film of a homopolymer of certain vinyl alkyl ethers are useful in the separation of various gases. Such homopolymers have a molecular weight of greater than 30,000 and the alkyl group of the vinyl alkyl monomer has from 4 to 20 carbon atoms with branching within the alkyl moiety at least at the carbon atom bonded to the ether oxygen or at the next adjacent carbon atom. These membranes show excellent hydrolytic stability, especially in the presence of acidic or basic gaseous components.

  4. Dietary free fatty acids form alkaline phosphatase-enriched microdomains in the intestinal brush border membrane

    DEFF Research Database (Denmark)

    Hansen, Gert H; Rasmussen, Karina; Niels-Christiansen, Lise-Lotte

    2011-01-01

    this membrane passage in organ cultured intestinal mucosal explants. We found that in addition to a rapid uptake into the cytoplasm, a fraction of the fatty acid analogs were inserted directly into the brush border membrane. Furthermore, a brief exposure of microvillar membrane vesicles to a fat mixture...... mimicking a physiological solution of dietary mixed micelles, rearranged the lipid raft microdomain organization of the membranes. Thus, the fat mixture generated a low-density subpopulation of microvillar detergent resistant membranes (DRMs) highly enriched in alkaline phosphatase (AP). Since this GPI-linked...... enzyme is the membrane protein in the brush border with the highest affinity for lipid rafts, this implies that free fatty acids selectively insert stably into these membrane microdomains. We have previously shown that absorption of dietary lipids transiently induce a selective endocytosis of AP from...

  5. On the translocation of botulinum and tetanus neurotoxins across the membrane of acidic intracellular compartments.

    Science.gov (United States)

    Pirazzini, Marco; Azarnia Tehran, Domenico; Leka, Oneda; Zanetti, Giulia; Rossetto, Ornella; Montecucco, Cesare

    2016-03-01

    Tetanus and botulinum neurotoxins are produced by anaerobic bacteria of the genus Clostridium and are the most poisonous toxins known, with 50% mouse lethal dose comprised within the range of 0.1-few nanograms per Kg, depending on the individual toxin. Botulinum neurotoxins are similarly toxic to humans and can therefore be considered for potential use in bioterrorism. At the same time, their neurospecificity and reversibility of action make them excellent therapeutics for a growing and heterogeneous number of human diseases that are characterized by a hyperactivity of peripheral nerve terminals. The complete crystallographic structure is available for some botulinum toxins, and reveals that they consist of four domains functionally related to the four steps of their mechanism of neuron intoxication: 1) binding to specific receptors of the presynaptic membrane; 2) internalization via endocytic vesicles; 3) translocation across the membrane of endocytic vesicles into the neuronal cytosol; 4) catalytic activity of the enzymatic moiety directed towards the SNARE proteins. Despite the many advances in understanding the structure-mechanism relationship of tetanus and botulinum neurotoxins, the molecular events involved in the translocation step have been only partially elucidated. Here we will review recent advances that have provided relevant insights on the process and discuss possible models that can be experimentally tested. This article is part of a Special Issue entitled: Pore-Forming Toxins edited by Mauro Dalla Serra and Franco Gambale. Copyright © 2015. Published by Elsevier B.V.

  6. Tetraspanin-enriched microdomains: a functional unit in cell plasma membranes.

    Science.gov (United States)

    Yáñez-Mó, María; Barreiro, Olga; Gordon-Alonso, Mónica; Sala-Valdés, Mónica; Sánchez-Madrid, Francisco

    2009-09-01

    Membrane lipids and proteins are non-randomly distributed and are unable to diffuse freely in the plane of the membrane. This is because of multiple constraints imposed both by the cortical cytoskeleton and by the preference of lipids and proteins to cluster into diverse and specialized membrane domains, including tetraspanin-enriched microdomains, glycosylphosphatidyl inositol-linked proteins nanodomains and caveolae, among others. Recent biophysical characterization of tetraspanin-enriched microdomains suggests that they might be specially suited for the regulation of avidity of adhesion receptors and the compartmentalization of enzymatic activities. Moreover, modulation by tetraspanins of the function of adhesion receptors involved in inflammation, lymphocyte activation, cancer and pathogen infection suggests potential as therapeutic targets. This review explores this emerging picture of tetraspanin microdomains and discusses the implications for cell adhesion, proteolysis and pathogenesis.

  7. Proteomic characterization of golgi membranes enriched from Arabidopsis suspension cell cultures

    DEFF Research Database (Denmark)

    Hansen, Sara Fasmer; Ebert, Berit; Rautengarten, Carsten

    2016-01-01

    The plant Golgi apparatus has a central role in the secretory pathway and is the principal site within the cell for the assembly and processing of macromolecules. The stacked membrane structure of the Golgi apparatus along with its interactions with the cytoskeleton and endoplasmic reticulum has...... historically made the isolation and purification of this organelle difficult. Density centrifugation has typically been used to enrich Golgi membranes from plant microsomal preparations, and aside from minor adaptations, the approach is still widely employed. Here we outline the enrichment of Golgi membranes...... from an Arabidopsis cell suspension culture that can be used to investigate the proteome of this organelle. We also provide a useful workflow for the examination of proteomic data as the result of multiple analyses. Finally, we highlight a simple technique to validate the subcellular localization...

  8. Methods of staining and visualization of sphingolipid enriched and non-enriched plasma membrane regions of Arabidopsis thaliana with fluorescent dyes and lipid analogues

    Directory of Open Access Journals (Sweden)

    Blachutzik Jörg O

    2012-08-01

    Full Text Available Abstract Background Sterols and Sphingolipids form lipid clusters in the plasma membranes of cell types throughout the animal and plant kingdoms. These lipid domains provide a medium for protein signaling complexes at the plasma membrane and are also observed to be principal regions of membrane contact at the inception of infection. We visualized different specific fluorescent lipophilic stains of the both sphingolipid enriched and non-sphingolipid enriched regions in the plasma membranes of live protoplasts of Arabidopsis thaliana. Results Lipid staining protocols for several fluorescent lipid analogues in plants are presented. The most emphasis was placed on successful protocols for the single and dual staining of sphingolipid enriched regions and exclusion of sphingolipid enriched regions on the plasma membrane of Arabidopsis thaliana protoplasts. A secondary focus was placed to ensure that these staining protocols presented still maintain cell viability. Furthermore, the protocols were successfully tested with the spectrally sensitive dye Laurdan. Conclusion Almost all existing staining procedures of the plasma membrane with fluorescent lipid analogues are specified for animal cells and tissues. In order to develop lipid staining protocols for plants, procedures were established with critical steps for the plasma membrane staining of Arabidopsis leaf tissue and protoplasts. The success of the plasma membrane staining protocols was additionally verified by measurements of lipid dynamics by the fluorescence recovery after photobleaching technique and by the observation of new phenomena such as time dependent lipid polarization events in living protoplasts, for which a putative physiological relevance is suggested.

  9. The effect of ultraviolet radiation on wheat root vesicles enriched in plasma membrane

    International Nuclear Information System (INIS)

    Wright, L.A. Jr.; Murphy, T.M.; Travis, R.L.

    1981-01-01

    The irradiation of plant cells with UV radiation (254 nm) causes various solutes to leak from the cells. Vesicles enriched in plasma membranes were prepared from wheat roots. These were used to determine whether UV radiation alters membrane function by direct action on the membranes and to distinguish between the chemical effects produced by high and low fluences of UV. The plasma membrane-associated K + -stimulated ATPase was very sensitive to UV radiation (100% inhibition with 2 ). ATPase activity measured in the absence of K + and K + -stimulated ATPase activity measured in the presence of diethylstilbestrol were much less sensitive. Lipid breakdown, as measured by malondialdehyde production, occurred only at UV fluences greater than 1.8 kJ/m 2 . (author)

  10. Hydrogen enrichment and separation from synthesis gas by the use of a membrane reactor

    International Nuclear Information System (INIS)

    Sanchez, J.M.; Barreiro, M.M.; Marono, M.

    2011-01-01

    One of the objectives of the CHRISGAS project was to study innovative gas separation and gas upgrading systems that have not been developed sufficiently yet to be tested at a demonstration scale within the time frame of the project, but which show some attractive merits and features for further development. In this framework CIEMAT studied, at bench scale, hydrogen enrichment and separation from syngas by the use of membranes and membrane catalytic reactors. In this paper results about hydrogen separation from synthesis gas by means of selective membranes are presented. Studies dealt with the evaluation of permeation and selectivity to hydrogen of prepared and pre-commercial Pd-based membranes. Whereas prepared membranes turned out to be non-selective, due to discontinuities of the palladium layer, studies conducted with the pre-commercial membrane showed that by means of a membrane reactor it is possible to completely separate hydrogen from the other gas components and produce pure hydrogen as a permeate stream, even in the case of complex reaction system (H 2 /CO/CO 2 /H 2 O) under WGS conditions gas mixtures. The advantages of using a water-gas shift membrane reactor (MR) over a traditional fixed bed reactor (TR) have also been studied. The experimental device included the pre-commercial Pd-based membrane and a commercial high temperature Fe-Cr-based, WGS catalyst, which was packed in the annulus between the membrane and the reactor outer shell. Results show that in the MR concept, removal of H 2 from the reaction side has a positive effect on WGS reaction, reaching higher CO conversion than in a traditional packed bed reactor at a given temperature. On increasing pressure on the reaction side permeation is enhanced and hence carbon monoxide conversion increases. -- Highlights: → H 2 enrichment and separation using a bench-scale membrane reactor MR is studied. → Permeation and selectivity to H 2 of Pd-based membranes was determined. → Complete separation

  11. Periodic harvesting of embryonic stem cells from a hollow-fiber membrane based four-compartment bioreactor.

    Science.gov (United States)

    Knöspel, Fanny; Freyer, Nora; Stecklum, Maria; Gerlach, Jörg C; Zeilinger, Katrin

    2016-01-01

    Different types of stem cells have been investigated for applications in drug screening and toxicity testing. In order to provide sufficient numbers of cells for such in vitro applications a scale-up of stem cell culture is necessary. Bioreactors for dynamic three-dimensional (3D) culture of growing cells offer the option for culturing large amounts of stem cells at high densities in a closed system. We describe a method for periodic harvesting of pluripotent stem cells (PSC) during expansion in a perfused 3D hollow-fiber membrane bioreactor, using mouse embryonic stem cells (mESC) as a model cell line. A number of 100 × 10(6) mESC were seeded in bioreactors in the presence of mouse embryonic fibroblasts (MEF) as feeder cells. Over a cultivation interval of nine days cells were harvested by trypsin perfusion and mechanical agitation every second to third culture day. A mean of 380 × 10(6) mESC could be removed with every harvest. Subsequent to harvesting, cells continued growing in the bioreactor, as determined by increasing glucose consumption and lactate production. Immunocytochemical staining and mRNA expression analysis of markers for pluripotency and the three germ layers showed a similar expression of most markers in the harvested cells and in mESC control cultures. In conclusion, successful expansion and harvesting of viable mESC from bioreactor cultures with preservation of sterility was shown. The present study is the first one showing the feasibility of periodic harvesting of adherent cells from a continuously perfused four-compartment bioreactor including further cultivation of remaining cells. © 2015 American Institute of Chemical Engineers.

  12. Amine Enrichment of Thin-Film Composite Membranes via Low Pressure Plasma Polymerization for Antimicrobial Adhesion.

    Science.gov (United States)

    Reis, Rackel; Dumée, Ludovic F; He, Li; She, Fenghua; Orbell, John D; Winther-Jensen, Bjorn; Duke, Mikel C

    2015-07-15

    Thin-film composite membranes, primarily based on poly(amide) (PA) semipermeable materials, are nowadays the dominant technology used in pressure driven water desalination systems. Despite offering superior water permeation and salt selectivity, their surface properties, such as their charge and roughness, cannot be extensively tuned due to the intrinsic fabrication process of the membranes by interfacial polymerization. The alteration of these properties would lead to a better control of the materials surface zeta potential, which is critical to finely tune selectivity and enhance the membrane materials stability when exposed to complex industrial waste streams. Low pressure plasma was employed to introduce amine functionalities onto the PA surface of commercially available thin-film composite (TFC) membranes. Morphological changes after plasma polymerization were analyzed by SEM and AFM, and average surface roughness decreased by 29%. Amine enrichment provided isoelectric point changes from pH 3.7 to 5.2 for 5 to 15 min of plasma polymerization time. Synchrotron FTIR mappings of the amine-modified surface indicated the addition of a discrete 60 nm film to the PA layer. Furthermore, metal affinity was confirmed by the enhanced binding of silver to the modified surface, supported by an increased antimicrobial functionality with demonstrable elimination of E. coli growth. Essential salt rejection was shown minimally compromised for faster polymerization processes. Plasma polymerization is therefore a viable route to producing functional amine enriched thin-film composite PA membrane surfaces.

  13. Interpretation of the measurement of ions fluxes through a biological membrane with a cellular compartment: example of the movements of sodium through the skin of frogs

    International Nuclear Information System (INIS)

    Morel, F.

    1959-01-01

    Two-way ion fluxes which can be measured in vitro through a living epithelial membrane (such as frog skin) by the indicator method take place across the cells which behave like an intermediate ionic 'compartment'. Two membranes and four fluxes have thus to be considered. Measurements in vitro of the total sodium fluxes as a function of the sodium concentration in the medium in contact with the external face of the skin have been interpreted in this spirit. Making use of certain hypotheses, the permeability coefficients for sodium of the two cellular membranes, the four sodium fluxes, the intracellular sodium concentration and the membrane potentials have been calculated for each value of the sodium concentration in the external medium. (author) [fr

  14. Monoolein lipid phases as incorporation and enrichment materials for membrane protein crystallization.

    Directory of Open Access Journals (Sweden)

    Ellen Wallace

    Full Text Available The crystallization of membrane proteins in amphiphile-rich materials such as lipidic cubic phases is an established methodology in many structural biology laboratories. The standard procedure employed with this methodology requires the generation of a highly viscous lipidic material by mixing lipid, for instance monoolein, with a solution of the detergent solubilized membrane protein. This preparation is often carried out with specialized mixing tools that allow handling of the highly viscous materials while minimizing dead volume to save precious membrane protein sample. The processes that occur during the initial mixing of the lipid with the membrane protein are not well understood. Here we show that the formation of the lipidic phases and the incorporation of the membrane protein into such materials can be separated experimentally. Specifically, we have investigated the effect of different initial monoolein-based lipid phase states on the crystallization behavior of the colored photosynthetic reaction center from Rhodobacter sphaeroides. We find that the detergent solubilized photosynthetic reaction center spontaneously inserts into and concentrates in the lipid matrix without any mixing, and that the initial lipid material phase state is irrelevant for productive crystallization. A substantial in-situ enrichment of the membrane protein to concentration levels that are otherwise unobtainable occurs in a thin layer on the surface of the lipidic material. These results have important practical applications and hence we suggest a simplified protocol for membrane protein crystallization within amphiphile rich materials, eliminating any specialized mixing tools to prepare crystallization experiments within lipidic cubic phases. Furthermore, by virtue of sampling a membrane protein concentration gradient within a single crystallization experiment, this crystallization technique is more robust and increases the efficiency of identifying productive

  15. Cell-Free and Cell-Based Approaches to Explore the Roles of Host Membranes and Lipids in the Formation of Viral Replication Compartment Induced by Tombusviruses.

    Science.gov (United States)

    Nagy, Peter D; Pogany, Judit; Xu, Kai

    2016-03-03

    Plant positive strand RNA viruses are intracellular infectious agents that take advantage of cellular lipids and membranes to support replication and protect viral RNA from degradation by host antiviral responses. In this review, we discuss how Tomato bushy stunt virus (TBSV) co-opts lipid transfer proteins and modulates lipid metabolism and transport to facilitate the assembly of the membrane-bound viral replicase complexes within intricate replication compartments. Identification and characterization of the proviral roles of specific lipids and proteins involved in lipid metabolism based on results from yeast (Saccharomyces cerevisiae) model host and cell-free approaches are discussed. The review also highlights the advantage of using liposomes with chemically defined composition to identify specific lipids required for TBSV replication. Remarkably, all the known steps in TBSV replication are dependent on cellular lipids and co-opted membranes.

  16. Enriched glucose and dextrin mannitol-based media modulates fibroblast behavior on bacterial cellulose membranes

    International Nuclear Information System (INIS)

    Stumpf, Taisa R.; Pértile, Renata A.N.; Rambo, Carlos R.; Porto, Luismar M.

    2013-01-01

    Bacterial cellulose (BC) produced by Gluconacetobacter hansenii is a suitable biopolymer for biomedical applications. In order to modulate the properties of BC and expand its use as substrate for tissue engineering mainly in the form of biomembranes, glucose or dextrin were added into a BC fermentation mannitol-based medium (BCGl and BCDe, respectively) under static culture conditions. SEM images showed effects on fiber density and porosity on both sides of the BC membranes. Both enriched media decreased the BET surface area, water holding capacity, and rehydration rate. Fourier transform infrared (attenuated total reflectance mode) spectroscopy (FTIR-ATR) analysis revealed no change in the chemical structure of BC. L929 fibroblast cells were seeded on all BC-based membranes and evaluated in aspects of cell adhesion, proliferation and morphology. BCG1 membranes showed the highest biological performance and hold promise for the use in tissue engineering applications. - Highlights: • Glucose and dextrin were used to modify culture media for BC production. • Microarchitecture of BC was different depending on the enriching agent. • Fibroblasts adhered on the surface of BC modified microarchitectures. • Fibroblasts adhered on glucose modified BC exhibited healthy cell morphology

  17. Enriched glucose and dextrin mannitol-based media modulates fibroblast behavior on bacterial cellulose membranes

    Energy Technology Data Exchange (ETDEWEB)

    Stumpf, Taisa R.; Pértile, Renata A.N. [Integrated Technologies Laboratory, Department of Chemical and Food Engineering (Brazil); Rambo, Carlos R., E-mail: rambo@intelab.ufsc.br [Department of Electrical Engineering, Federal University of Santa Catarina, Florianópolis 88040-900 (Brazil); Porto, Luismar M. [Integrated Technologies Laboratory, Department of Chemical and Food Engineering (Brazil)

    2013-12-01

    Bacterial cellulose (BC) produced by Gluconacetobacter hansenii is a suitable biopolymer for biomedical applications. In order to modulate the properties of BC and expand its use as substrate for tissue engineering mainly in the form of biomembranes, glucose or dextrin were added into a BC fermentation mannitol-based medium (BCGl and BCDe, respectively) under static culture conditions. SEM images showed effects on fiber density and porosity on both sides of the BC membranes. Both enriched media decreased the BET surface area, water holding capacity, and rehydration rate. Fourier transform infrared (attenuated total reflectance mode) spectroscopy (FTIR-ATR) analysis revealed no change in the chemical structure of BC. L929 fibroblast cells were seeded on all BC-based membranes and evaluated in aspects of cell adhesion, proliferation and morphology. BCG1 membranes showed the highest biological performance and hold promise for the use in tissue engineering applications. - Highlights: • Glucose and dextrin were used to modify culture media for BC production. • Microarchitecture of BC was different depending on the enriching agent. • Fibroblasts adhered on the surface of BC modified microarchitectures. • Fibroblasts adhered on glucose modified BC exhibited healthy cell morphology.

  18. Venture from the Interior-Herpesvirus pUL31 Escorts Capsids from Nucleoplasmic Replication Compartments to Sites of Primary Envelopment at the Inner Nuclear Membrane.

    Science.gov (United States)

    Bailer, Susanne M.

    2017-11-25

    Herpesviral capsid assembly is initiated in the nucleoplasm of the infected cell. Size constraints require that newly formed viral nucleocapsids leave the nucleus by an evolutionarily conserved vescular transport mechanism called nuclear egress. Mature capsids released from the nucleoplasm are engaged in a membrane-mediated budding process, composed of primary envelopment at the inner nuclear membrane and de-envelopment at the outer nuclear membrane. Once in the cytoplasm, the capsids receive their secondary envelope for maturation into infectious virions. Two viral proteins conserved throughout the herpesvirus family, the integral membrane protein pUL34 and the phosphoprotein pUL31, form the nuclear egress complex required for capsid transport from the infected nucleus to the cytoplasm. Formation of the nuclear egress complex results in budding of membrane vesicles revealing its function as minimal virus-encoded membrane budding and scission machinery. The recent structural analysis unraveled details of the heterodimeric nuclear egress complex and the hexagonal coat it forms at the inside of budding vesicles to drive primary envelopment. With this review, I would like to present the capsid-escort-model where pUL31 associates with capsids in nucleoplasmic replication compartments for escort to sites of primary envelopment thereby coupling capsid maturation and nuclear egress.

  19. Purification of the Membrane Compartment for Endoplasmic Reticulum-associated Degradation of Exogenous Antigens in Cross-presentation.

    Science.gov (United States)

    Imai, Jun; Otani, Mayu; Sakai, Takahiro; Hatta, Shinichi

    2017-08-21

    Dendritic cells (DCs) are highly capable of processing and presenting internalized exogenous antigens upon major histocompatibility class (MHC) I molecules also known as cross-presentation (CP). CP plays an important role not only in the stimulation of naïve CD8 + T cells and memory CD8 + T cells for infectious and tumor immunity but also in the inactivation of self-acting naïve T cells by T cell anergy or T cell deletion. Although the critical molecular mechanism of CP remains to be elucidated, accumulating evidence indicates that exogenous antigens are processed through endoplasmic reticulum-associated degradation (ERAD) after export from non-classical endocytic compartments. Until recently, characterizations of these endocytic compartments were limited because there were no specific molecular markers other than exogenous antigens. The method described here is a new vesicle isolation protocol, which allows for the purification of these endocytic compartments. Using this purified microsome, we reconstituted the ERAD-like transport, ubiquitination, and processing of the exogenous antigen in vitro, suggesting that the ubiquitin-proteasome system processed the exogenous antigen after export from this cellular compartment. This protocol can be further applied to other cell types to clarify the molecular mechanism of CP.

  20. Tubulation of Class II MHC Compartments Is Microtubule Dependent and Involves Multiple Endolysosomal Membrane Proteins in Primary Dendritic Cells1

    Science.gov (United States)

    Vyas, Jatin M.; Kim, You-Me; Artavanis-Tsakonas, Katerina; Love, J. Christopher; Van der Veen, Annemarthe G.; Ploegh, Hidde L.

    2009-01-01

    Immature dendritic cells (DCs) capture exogenous Ags in the periphery for eventual processing in endolysosomes. Upon maturation by TLR agonists, DCs deliver peptide-loaded class II MHC molecules from these compartments to the cell surface via long tubular structures (endolysosomal tubules). The nature and rules that govern the movement of these DC compartments are unknown. In this study, we demonstrate that the tubules contain multiple proteins including the class II MHC molecules and LAMP1, a lysosomal resident protein, as well as CD63 and CD82, members of the tetraspanin family. Endolysosomal tubules can be stained with acidotropic dyes, indicating that they are extensions of lysosomes. However, the proper trafficking of class II MHC molecules themselves is not necessary for endolysosomal tubule formation. DCs lacking MyD88 can also form endolysosomal tubules, demonstrating that MyD88-dependent TLR activation is not necessary for the formation of this compartment. Endolysosomal tubules in DCs exhibit dynamic and saltatory movement, including bidirectional travel. Measured velocities are consistent with motor-based movement along microtubules. Indeed, nocodazole causes the collapse of endolysosomal tubules. In addition to its association with microtubules, endolysosomal tubules follow the plus ends of microtubules as visualized in primary DCs expressing end binding protein 1 (EB1)-enhanced GFP. PMID:17513769

  1. Tubulation of class II MHC compartments is microtubule dependent and involves multiple endolysosomal membrane proteins in primary dendritic cells.

    Science.gov (United States)

    Vyas, Jatin M; Kim, You-Me; Artavanis-Tsakonas, Katerina; Love, J Christopher; Van der Veen, Annemarthe G; Ploegh, Hidde L

    2007-06-01

    Immature dendritic cells (DCs) capture exogenous Ags in the periphery for eventual processing in endolysosomes. Upon maturation by TLR agonists, DCs deliver peptide-loaded class II MHC molecules from these compartments to the cell surface via long tubular structures (endolysosomal tubules). The nature and rules that govern the movement of these DC compartments are unknown. In this study, we demonstrate that the tubules contain multiple proteins including the class II MHC molecules and LAMP1, a lysosomal resident protein, as well as CD63 and CD82, members of the tetraspanin family. Endolysosomal tubules can be stained with acidotropic dyes, indicating that they are extensions of lysosomes. However, the proper trafficking of class II MHC molecules themselves is not necessary for endolysosomal tubule formation. DCs lacking MyD88 can also form endolysosomal tubules, demonstrating that MyD88-dependent TLR activation is not necessary for the formation of this compartment. Endolysosomal tubules in DCs exhibit dynamic and saltatory movement, including bidirectional travel. Measured velocities are consistent with motor-based movement along microtubules. Indeed, nocodazole causes the collapse of endolysosomal tubules. In addition to its association with microtubules, endolysosomal tubules follow the plus ends of microtubules as visualized in primary DCs expressing end binding protein 1 (EB1)-enhanced GFP.

  2. Enrichment and proteomic analysis of plasma membrane from rat dorsal root ganglions

    Directory of Open Access Journals (Sweden)

    Lin Yong

    2009-11-01

    Full Text Available Abstract Background Dorsal root ganglion (DRG neurons are primary sensory neurons that conduct neuronal impulses related to pain, touch and temperature senses. Plasma membrane (PM of DRG cells plays important roles in their functions. PM proteins are main performers of the functions. However, mainly due to the very low amount of DRG that leads to the difficulties in PM sample collection, few proteomic analyses on the PM have been reported and it is a subject that demands further investigation. Results By using aqueous polymer two-phase partition in combination with high salt and high pH washing, PMs were efficiently enriched, demonstrated by western blot analysis. A total of 954 non-redundant proteins were identified from the plasma membrane-enriched preparation with CapLC-MS/MS analysis subsequent to protein separation by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE or shotgun digestion. 205 (21.5% of the identified proteins were unambiguously assigned as PM proteins, including a large number of signal proteins, receptors, ion channel and transporters. Conclusion The aqueous polymer two-phase partition is a simple, rapid and relatively inexpensive method. It is well suitable for the purification of PMs from small amount of tissues. Therefore, it is reasonable for the DRG PM to be enriched by using aqueous two-phase partition as a preferred method. Proteomic analysis showed that DRG PM was rich in proteins involved in the fundamental biological processes including material exchange, energy transformation and information transmission, etc. These data would help to our further understanding of the fundamental DRG functions.

  3. Quantitative membrane proteomics reveals a role for tetraspanin enriched microdomains during entry of human cytomegalovirus.

    Directory of Open Access Journals (Sweden)

    Kasinath Viswanathan

    Full Text Available Human cytomegalovirus (HCMV depends on and modulates multiple host cell membrane proteins during each stage of the viral life cycle. To gain a global view of the impact of HCMV-infection on membrane proteins, we analyzed HCMV-induced changes in the abundance of membrane proteins in fibroblasts using stable isotope labeling with amino acids (SILAC, membrane fractionation and protein identification by two-dimensional liquid chromatography and tandem mass spectrometry. This systematic approach revealed that CD81, CD44, CD98, caveolin-1 and catenin delta-1 were down-regulated during infection whereas GRP-78 was up-regulated. Since CD81 downregulation was also observed during infection with UV-inactivated virus we hypothesized that this tetraspanin is part of the viral entry process. Interestingly, additional members of the tetraspanin family, CD9 and CD151, were also downregulated during HCMV-entry. Since tetraspanin-enriched microdomains (TEM cluster host cell membrane proteins including known CMV receptors such as integrins, we studied whether TEMs are required for viral entry. When TEMs were disrupted with the cholesterol chelator methyl-β-cylcodextrin, viral entry was inhibited and this inhibition correlated with reduced surface levels of CD81, CD9 and CD151, whereas integrin levels remained unchanged. Furthermore, simultaneous siRNA-mediated knockdown of multiple tetraspanins inhibited viral entry whereas individual knockdown had little effect suggesting essential, but redundant roles for individual tetraspanins during entry. Taken together, our data suggest that TEM act as platforms for receptors utilized by HCMV for entry into cells.

  4. Patellofemoral compartment

    International Nuclear Information System (INIS)

    Brown, T.; Quinn, S.F.; Erickson, S.J.; Cox, I.

    1990-01-01

    This paper evaluates the normal and abnormal patellofemoral compartment with axial MR imaging. Anatomic cryotome sections of the patellofemoral compartment were correlated with the corresponding MR images for identification of ligamentous structures and cartilaginous surfaces. Two hundred fifty-four patients who underwent both arthroscopy and axial MR imaging of the patellofemoral compartment underwent axial MR examinations, which included gradient-echo (TR 23, TE 14, flip angle 30 degrees), T1- weighted (TR 400, TE 20), and proton and T2-weighted (2,500/20/80) sequences. The results from the cryotome-MR correlation show that axial MR images of the patellofemoral compartment accurately depict the major ligamentous and cartilaginous components. The MR arthroscopic correlation showed that all pulse sequences were unreliable in depicting the more superficial changes of chondromalacia and the evaluation on synovial plica

  5. Compartment syndromes

    Science.gov (United States)

    Mubarak, S. J.; Pedowitz, R. A.; Hargens, A. R.

    1989-01-01

    The compartment syndrome is defined as a condition in which high pressure within a closed fascial space (muscle compartment) reduces capillary blood perfusion below the level necessary for tissue viability'. This condition occurs in acute and chronic (exertional) forms, and may be secondary to a variety of causes. The end-result of an extended period of elevated intramuscular pressure may be the development of irreversible tissue injury and Volkmann's contracture. The goal of treatment of the compartment syndrome is the reduction of intracompartmental pressure thus facilitating reperfusion of ischaemic tissue and this goal may be achieved by decompressive fasciotomy. Controversy exists regarding the critical pressure-time thresholds for surgical decompression and the optimal diagnostic methods of measuring intracompartmental pressures. This paper will update and review some current knowledge regarding the pathophysiology, aetiology, diagnosis, and treatment of the acute compartment syndrome.

  6. Developmental distribution of the plasma membrane-enriched proteome in the maize primary root growth zone

    Directory of Open Access Journals (Sweden)

    Zhe eZhang

    2013-03-01

    Full Text Available Within the growth zone of the maize primary root, there are well-defined patterns of spatial and temporal organization of cell division and elongation. However, the processes underlying this organization remain poorly understood. To gain additional insights into the differences amongst the defined regions, we performed a proteomic analysis focusing on fractions enriched for plasma membrane (PM proteins. The PM is the interface between the plant cell and the apoplast and/or extracellular space. As such, it is a key structure involved in the exchange of nutrients and other molecules as well as in the integration of signals that regulate growth and development. Despite the important functions of PM-localized proteins in mediating these processes, a full understanding of dynamic changes in PM proteomes is often impeded by low relative concentrations relative to total proteins. Using a relatively simple strategy of treating microsomal fractions with Brij-58 detergent to enrich for PM proteins, we compared the developmental distribution of proteins within the root growth zone which revealed a number of previously known as well as novel proteins with interesting patterns of abundance. For instance, the quantitative proteomic analysis detected a gradient of PM aquaporin proteins similar to that previously reported using immunoblot analyses, confirming the veracity of this strategy. Cellulose synthases increased in abundance with increasing distance from the root apex, consistent with expected locations of cell wall deposition. The similar distribution pattern for Brittle-stalk-2-like protein 3 implicate that this protein may also have cell wall related functions. These results show that the simplified PM enrichment method previously demonstrated in Arabidopsis can be successfully applied to completely unrelated plant tissues and provide insights into differences in the PM proteome throughout growth and development zones of the maize primary root.

  7. Developmental distribution of the plasma membrane-enriched proteome in the maize primary root growth zone.

    Science.gov (United States)

    Zhang, Zhe; Voothuluru, Priyamvada; Yamaguchi, Mineo; Sharp, Robert E; Peck, Scott C

    2013-01-01

    Within the growth zone of the maize primary root, there are well-defined patterns of spatial and temporal organization of cell division and elongation. However, the processes underlying this organization remain poorly understood. To gain additional insights into the differences amongst the defined regions, we performed a proteomic analysis focusing on fractions enriched for plasma membrane (PM) proteins. The PM is the interface between the plant cell and the apoplast and/or extracellular space. As such, it is a key structure involved in the exchange of nutrients and other molecules as well as in the integration of signals that regulate growth and development. Despite the important functions of PM-localized proteins in mediating these processes, a full understanding of dynamic changes in PM proteomes is often impeded by low relative concentrations relative to total proteins. Using a relatively simple strategy of treating microsomal fractions with Brij-58 detergent to enrich for PM proteins, we compared the developmental distribution of proteins within the root growth zone which revealed a number of previously known as well as novel proteins with interesting patterns of abundance. For instance, the quantitative proteomic analysis detected a gradient of PM aquaporin proteins similar to that previously reported using immunoblot analyses, confirming the veracity of this strategy. Cellulose synthases increased in abundance with increasing distance from the root apex, consistent with expected locations of cell wall deposition. The similar distribution pattern for Brittle-stalk-2-like protein implicates that this protein may also have cell wall related functions. These results show that the simplified PM enrichment method previously demonstrated in Arabidopsis can be successfully applied to completely unrelated plant tissues and provide insights into differences in the PM proteome throughout growth and development zones of the maize primary root.

  8. Arabidopsis cortical microtubules position cellulose synthase delivery to the plasma membrane and interact with cellulose synthase trafficking compartments.

    NARCIS (Netherlands)

    Gutierrez, R.; Lindeboom, J.J.; Paredez, A.R.; Emons, A.M.C.; Ehrhardt, D.W.

    2009-01-01

    Plant cell morphogenesis relies on the organization and function of two polymer arrays separated by the plasma membrane: the cortical microtubule cytoskeleton and cellulose microfibrils in the cell wall. Studies using in vivo markers confirmed that one function of the cortical microtubule array is

  9. Effect of membranes on oxygen transfer rate and consumption within a newly developed three-compartment bioartificial liver device: Advanced experimental and theoretical studies.

    Science.gov (United States)

    Hilal-Alnaqbi, Ali; Mourad, Abdel-Hamid I; Yousef, Basem F

    2014-01-01

    A mathematical model is developed to predict oxygen transfer in the fiber-in-fiber (FIF) bioartificial liver device. The model parameters are taken from the constructed and tested FIF modules. We extended the Krogh cylinder model by including one more zone for oxygen transfer. Cellular oxygen uptake was based on Michaelis-Menten kinetics. The effect of varying a number of important model parameters is investigated, including (1) oxygen partial pressure at the inlet, (2) the hydraulic permeability of compartment B (cell region), (3) the hydraulic permeability of the inner membrane, and (4) the oxygen diffusivity of the outer membrane. The mathematical model is validated by comparing its output against the experimentally acquired values of an oxygen transfer rate and the hydrostatic pressure drop. Three governing simultaneous linear differential equations are derived to predict and validate the experimental measurements, e.g., the flow rate and the hydrostatic pressure drop. The model output simulated the experimental measurements to a high degree of accuracy. The model predictions show that the cells in the annulus can be oxygenated well even at high cell density or at a low level of gas phase PG if the value of the oxygen diffusion coefficient Dm is 16 × 10(-5) . The mathematical model also shows that the performance of the FIF improves by increasing the permeability of polypropylene membrane (inner fiber). Moreover, the model predicted that 60% of plasma has access to the cells in the annulus within the first 10% of the FIF bioreactor axial length for a specific polypropylene membrane permeability and can reach 95% within the first 30% of its axial length. © 2013 International Union of Biochemistry and Molecular Biology, Inc.

  10. Simplified Enrichment of Plasma Membrane Proteins from Arabidopsis thaliana Seedlings Using Differential Centrifugation and Brij-58 Treatment.

    Science.gov (United States)

    Collins, Carina A; Leslie, Michelle E; Peck, Scott C; Heese, Antje

    2017-01-01

    The plasma membrane (PM) forms a barrier between a plant cell and its environment. Proteins at this subcellular location play diverse and complex roles, including perception of extracellular signals to coordinate cellular changes. Analyses of PM proteins, however, are often limited by the relatively low abundance of these proteins in the total cellular protein pool. Techniques traditionally used for enrichment of PM proteins are time consuming, tedious, and require extensive optimization. Here, we provide a simple and reproducible enrichment procedure for PM proteins from Arabidopsis thaliana seedlings starting from total microsomal membranes isolated by differential centrifugation. To enrich for PM proteins, total microsomes are treated with the nonionic detergent Brij-58 to decrease the abundance of contaminating organellar proteins. This protocol combined with the genetic resources available in Arabidopsis provides a powerful tool that will enhance our understanding of proteins at the PM.

  11. Development of Nanofiller-Modulated Polymeric Oxygen Enrichment Membranes for Reduction of Nitrogen Oxides in Coal Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Jianzhong Lou; Shamsuddin Ilias

    2010-12-31

    North Carolina A&T State University in Greensboro, North Carolina, has undertaken this project to develop the knowledge and the material to improve the oxygen-enrichment polymer membrane, in order to provide high-grade oxygen-enriched streams for coal combustion and gasification applications. Both experimental and theoretical approaches were used in this project. The membranes evaluated thus far include single-walled carbon nano-tube, nano-fumed silica polydimethylsiloxane (PDMS), and zeolite-modulated polyimide membranes. To document the nanofiller-modulated polymer, molecular dynamics simulations have been conducted to calculate the theoretical oxygen molecular diffusion coefficient and nitrogen molecular coefficient inside single-walled carbon nano-tube PDMS membranes, in order to predict the effect of the nano-tubes on the gas-separation permeability. The team has performed permeation and diffusion experiments using polymers with nano-silica particles, nano-tubes, and zeolites as fillers; studied the influence of nano-fillers on the self diffusion, free volume, glass transition, oxygen diffusion and solubility, and perm-selectivity of oxygen in polymer membranes; developed molecular models of single-walled carbon nano-tube and nano-fumed silica PDMS membranes, and zeolites-modulated polyimide membranes. This project partially supported three graduate students (two finished degrees and one transferred to other institution). This project has resulted in two journal publications and additional publications will be prepared in the near future.

  12. Coronavirus and influenza virus proteolytic priming takes place in tetraspanin-enriched membrane microdomains.

    Science.gov (United States)

    Earnest, James T; Hantak, Michael P; Park, Jung-Eun; Gallagher, Tom

    2015-06-01

    Coronaviruses (CoVs) and low-pathogenicity influenza A viruses (LP IAVs) depend on target cell proteases to cleave their viral glycoproteins and prime them for virus-cell membrane fusion. Several proteases cluster into tetraspanin-enriched microdomains (TEMs), suggesting that TEMs are preferred virus entry portals. Here we found that several CoV receptors and virus-priming proteases were indeed present in TEMs. Isolated TEMs, when mixed with CoV and LP IAV pseudoparticles, cleaved viral fusion proteins to fusion-primed fragments and potentiated viral transductions. That entering viruses utilize TEMs as a protease source was further confirmed using tetraspanin antibodies and tetraspanin short hairpin RNAs (shRNAs). Tetraspanin antibodies inhibited CoV and LP IAV infections, but their virus-blocking activities were overcome by expressing excess TEM-associated proteases. Similarly, cells with reduced levels of the tetraspanin CD9 resisted CoV pseudoparticle transductions but were made susceptible by overproducing TEM-associated proteases. These findings indicated that antibodies and CD9 depletions interfere with viral proteolytic priming in ways that are overcome by surplus proteases. TEMs appear to be exploited by some CoVs and LP IAVs for appropriate coengagement with cell receptors and proteases. Enveloped viruses use their surface glycoproteins to catalyze membrane fusion, an essential cell entry step. Host cell components prime these viral surface glycoproteins to catalyze membrane fusion at specific times and places during virus cell entry. Among these priming components are proteases, which cleave viral surface glycoproteins, unleashing them to refold in ways that catalyze virus-cell membrane fusions. For some enveloped viruses, these proteases are known to reside on target cell surfaces. This research focuses on coronavirus and influenza A virus cell entry and identifies TEMs as sites of viral proteolysis, thereby defining subcellular locations of virus

  13. Syndecans reside in sphingomyelin-enriched low-density fractions of the plasma membrane isolated from a parathyroid cell line.

    Directory of Open Access Journals (Sweden)

    Katarzyna A Podyma-Inoue

    Full Text Available BACKGROUND: Heparan sulfate proteoglycans (HSPGs are one of the basic constituents of plasma membranes. Specific molecular interactions between HSPGs and a number of extracellular ligands have been reported. Mechanisms involved in controlling the localization and abundance of HSPG on specific domains on the cell surface, such as membrane rafts, could play important regulatory roles in signal transduction. METHODOLOGY/PRINCIPAL FINDINGS: Using metabolic radiolabeling and sucrose-density gradient ultracentrifugation techniques, we identified [(35S]sulfate-labeled macromolecules associated with detergent-resistant membranes (DRMs isolated from a rat parathyroid cell line. DRM fractions showed high specific radioactivity ([(35S]sulfate/mg protein, implying the specific recruitment of HSPGs to the membrane rafts. Identity of DRM-associated [(35S]sulfate-labeled molecules as HSPGs was confirmed by Western blotting with antibodies that recognize heparan sulfate (HS-derived epitope. Analyses of core proteins by SDS-PAGE revealed bands with an apparent MW of syndecan-4 (30-33 kDa and syndecan-1 (70 kDa suggesting the presence of rafts with various HSPG species. DRM fractions enriched with HSPGs were characterized by high sphingomyelin content and found to only partially overlap with the fractions enriched in ganglioside GM1. HSPGs could be also detected in DRMs even after prior treatment of cells with heparitinase. CONCLUSIONS/SIGNIFICANCE: Both syndecan-1 and syndecan-4 have been found to specifically associate with membrane rafts and their association seemed independent of intact HS chains. Membrane rafts in which HSPGs reside were also enriched with sphingomyelin, suggesting their possible involvement in FGF signaling. Further studies, involving proteomic characterization of membrane domains containing HSPGs might improve our knowledge on the nature of HSPG-ligand interactions and their role in different signaling platforms.

  14. Fabrication of Novel Hydrogel with Berberine-Enriched Carboxymethylcellulose and Hyaluronic Acid as an Anti-Inflammatory Barrier Membrane

    Directory of Open Access Journals (Sweden)

    Yu-Chih Huang

    2016-01-01

    Full Text Available An antiadhesion barrier membrane is an important biomaterial for protecting tissue from postsurgical complications. However, there is room to improve these membranes. Recently, carboxymethylcellulose (CMC incorporated with hyaluronic acid (HA as an antiadhesion barrier membrane and drug delivery system has been reported to provide excellent tissue regeneration and biocompatibility. The aim of this study was to fabricate a novel hydrogel membrane composed of berberine-enriched CMC prepared from bark of the P. amurense tree and HA (PE-CMC/HA. In vitro anti-inflammatory properties were evaluated to determine possible clinical applications. The PE-CMC/HA membranes were fabricated by mixing PE-CMC and HA as a base with the addition of polyvinyl alcohol to form a film. Tensile strength and ultramorphology of the membrane were evaluated using a universal testing machine and scanning electron microscope, respectively. Berberine content of the membrane was confirmed using a UV-Vis spectrophotometer at a wavelength of 260 nm. Anti-inflammatory property of the membrane was measured using a Griess reaction assay. Our results showed that fabricated PE-CMC/HA releases berberine at a concentration of 660 μg/ml while optimal plasticity was obtained at a 30 : 70 PE-CMC/HA ratio. The berberine-enriched PE-CMC/HA had an inhibited 60% of inflammation stimulated by LPS. These results suggest that the PE-CMC/HA membrane fabricated in this study is a useful anti-inflammatory berberine release system.

  15. Applicability of a liquid membrane in enrichment and determination of nickel traces from natural waters

    Energy Technology Data Exchange (ETDEWEB)

    Dominguez-Lledo, F.C.; Diaz-Lopez, I.C. [University of Havana, Department of Analytical Chemistry, Faculty of Chemistry, Havana (Cuba); Galindo-Riano, Maria D.; Garcia-Vargas, M.; Granado-Castro, M.D. [University of Cadiz, Department of Analytical Chemistry, Faculty of Sciences, Cadiz (Spain)

    2007-09-15

    In this work, a bulk liquid membrane method has been applied for Ni enrichment and separation from natural waters. The carrier-mediated transport was accomplished by pyridine-2-acetaldehyde benzoylhydrazone dissolved in toluene as a complexing agent. The preconcentration was achieved through pH control of source and receiving solutions via a counterflow of protons. The main variables were optimized by using a modified simplex technique. High transport efficiencies (101.2 {+-} 1.8-99.7 {+-} 4.2%) were provided by the carrier for nickel ions in a receiving phase of 0.31 mol L{sup -1} nitric acid after 9-13 h depending on sample salinity. The precision of the method was 2.05% (without a saline matrix) and 4.04% (with 40 g L{sup -1} NaCl) at the 95% confidence level and the detection limit of the blank was 0.015 {mu}g L{sup -1} Ni for detection by atomic absorption spectroscopy. The applicability of the method was tested on certified reference and real water samples with successful results, even for saline samples. The relative errors were -0.60% for certified reference materials and ranged from -0.39 to 2.90% and from 0.3 to 11.05% for real samples, obtained by comparison of inductively coupled plasma mass spectrometry and adsorptive cathodic stripping voltammetry measurements, respectively. (orig.)

  16. In vitro and in vivo phosphorylation of polypeptides in plasma membrane and tonoplast-enriched fractions from barley roots

    International Nuclear Information System (INIS)

    Garbarino, J.E.; Hurkman, W.J.; Tanaka, C.K.; DuPont, F.M.

    1991-01-01

    Phosphorylation of polypeptides in membrane fractions from barley (Hordeum vulgare L. cv CM 72) roots was compared in in vitro and in vivo assays to assess the potential role of protein kinases in modification of membrane transport. Membrane fractions enriched in endoplasmic reticulum, tonoplast, and plasma membrane were isolated using sucrose gradients and the membrane polypeptides separated using sodium dodecyl sulfate polyacrylamide gel electrophoresis. When the membrane fractions were incubated with γ[p 32 P]ATP, phosphorylation occurred almost exclusively in the plasma membrane fraction. Phosphorylation of a band at 38 kilodaltons increased as the concentration of Mg 2+ was decreased from millimolar to micromolar levels. Phosphorylation of bands at 125, 86, 58, 46 and 28 kilodaltons required millimolar Mg 2+ concentrations and was greatly enhanced by Ca 2+ . When roots of intact plants were labeled with [ 32 P]orthophosphate, polypeptides at approximately 135, 166, 90, 46 to 53, 32, 28, and 19 kilodaltons were labeled in the plasma membrane fraction and polypeptides at approximately 73, 66, and 48 kilodaltons were labeled in the tonoplast fraction. Treatment of the roots of intact plants with 150 millimolar NaCl resulted in increased phosphorylation of some polypeptides while treatment with 100 mM NaCl had no effect

  17. Preterm labor and preterm premature rupture of membranes have a different pattern in the involved compartments of acute histologoic chorioamnionitis and/or funisitis: Patho-physiologic implication related to different clinical manifestations.

    Science.gov (United States)

    Park, Chan-Wook; Park, Joong Shin; Moon, Kyung Chul; Jun, Jong Kwan; Yoon, Bo Hyun

    2016-06-01

    It is unknown whether histo-topographic findings about the involved compartments (i.e., choriodecidua, amnion, chorionic-plate) of acute-histologic chorioamnionitis (acute-HCA) and/or funisitis according to the presence or absence of intra-amniotic inflammation (IAI) and/or fetal inflammatory response syndrome (FIRS) are different between preterm labor and intact membranes (PTL) and preterm premature rupture of membranes (preterm-PROM). The involved compartments of acute-HCA and/or funisitis were examined in 161 singleton preterm-births ( 0.1). However, IAI(+)/FIRS(+) group had a significantly higher rate of inflammation in each compartment than IAI(+)/FIRS(-) group in both PTL and preterm-PROM (each-for P < 0.05). We first demonstrated that PTL and preterm-PROM had a different pattern in the involved compartments of acute-HCA and/or funisitis in the IAI(-)/FIRS(--) group and in the change of involved compartments from IAI(-)/FIRS(-) to IAI(+)/FIRS(-). © 2016 Japanese Society of Pathology and John Wiley & Sons Australia, Ltd.

  18. The Inner Membrane Complex Sub-compartment Proteins Critical for Replication of the Apicomplexan Parasite Toxoplasma gondii Adopt a Pleckstrin Homology Fold*

    Science.gov (United States)

    Tonkin, Michelle L.; Beck, Josh R.; Bradley, Peter J.; Boulanger, Martin J.

    2014-01-01

    Toxoplasma gondii, an apicomplexan parasite prevalent in developed nations, infects up to one-third of the human population. The success of this parasite depends on several unique structures including an inner membrane complex (IMC) that lines the interior of the plasma membrane and contains proteins important for gliding motility and replication. Of these proteins, the IMC sub-compartment proteins (ISPs) have recently been shown to play a role in asexual T. gondii daughter cell formation, yet the mechanism is unknown. Complicating mechanistic characterization of the ISPs is a lack of sequence identity with proteins of known structure or function. In support of elucidating the function of ISPs, we first determined the crystal structures of representative members TgISP1 and TgISP3 to a resolution of 2.10 and 2.32 Å, respectively. Structural analysis revealed that both ISPs adopt a pleckstrin homology fold often associated with phospholipid binding or protein-protein interactions. Substitution of basic for hydrophobic residues in the region that overlays with phospholipid binding in related pleckstrin homology domains, however, suggests that ISPs do not retain phospholipid binding activity. Consistent with this observation, biochemical assays revealed no phospholipid binding activity. Interestingly, mapping of conserved surface residues combined with crystal packing analysis indicates that TgISPs have functionally repurposed the phospholipid-binding site likely to coordinate protein partners. Recruitment of larger protein complexes may also be aided through avidity-enhanced interactions resulting from multimerization of the ISPs. Overall, we propose a model where TgISPs recruit protein partners to the IMC to ensure correct progression of daughter cell formation. PMID:24675080

  19. Assessing the effects of iron enrichment across holobiont compartments reveals reduced microbial nitrogen fixation in the Red Sea coral Pocillopora verrucosa

    KAUST Repository

    Radecker, Nils; Pogoreutz, Claudia; Ziegler, Maren; Ashok, Ananya; Barreto, Marcelle M.; Chaidez, Veronica; Grupstra, Carsten G. B.; Ng, Yi Mei; Perna, Gabriela; Aranda, Manuel; Voolstra, Christian R.

    2017-01-01

    The productivity of coral reefs in oligotrophic tropical waters is sustained by an efficient uptake and recycling of nutrients. In reef-building corals, the engineers of these ecosystems, this nutrient recycling is facilitated by a constant exchange of nutrients between the animal host and endosymbiotic photosynthetic dinoflagellates (zooxanthellae), bacteria, and other microbes. Due to the complex interactions in this so-called coral holobiont, it has proven difficult to understand the environmental limitations of productivity in corals. Among others, the micronutrient iron has been proposed to limit primary productivity due to its essential role in photosynthesis and bacterial processes. Here, we tested the effect of iron enrichment on the physiology of the coral Pocillopora verrucosa from the central Red Sea during a 12-day experiment. Contrary to previous reports, we did not see an increase in zooxanthellae population density or gross photosynthesis. Conversely, respiration rates were significantly increased, and microbial nitrogen fixation was significantly decreased. Taken together, our data suggest that iron is not a limiting factor of primary productivity in Red Sea corals. Rather, increased metabolic demands in response to iron enrichment, as evidenced by increased respiration rates, may reduce carbon (i.e., energy) availability in the coral holobiont, resulting in reduced microbial nitrogen fixation. This decrease in nitrogen supply in turn may exacerbate the limitation of other nutrients, creating a negative feedback loop. Thereby, our results highlight that the effects of iron enrichment appear to be strongly dependent on local environmental conditions and ultimately may depend on the availability of other nutrients.

  20. Assessing the effects of iron enrichment across holobiont compartments reveals reduced microbial nitrogen fixation in the Red Sea coral Pocillopora verrucosa

    KAUST Repository

    Radecker, Nils

    2017-07-31

    The productivity of coral reefs in oligotrophic tropical waters is sustained by an efficient uptake and recycling of nutrients. In reef-building corals, the engineers of these ecosystems, this nutrient recycling is facilitated by a constant exchange of nutrients between the animal host and endosymbiotic photosynthetic dinoflagellates (zooxanthellae), bacteria, and other microbes. Due to the complex interactions in this so-called coral holobiont, it has proven difficult to understand the environmental limitations of productivity in corals. Among others, the micronutrient iron has been proposed to limit primary productivity due to its essential role in photosynthesis and bacterial processes. Here, we tested the effect of iron enrichment on the physiology of the coral Pocillopora verrucosa from the central Red Sea during a 12-day experiment. Contrary to previous reports, we did not see an increase in zooxanthellae population density or gross photosynthesis. Conversely, respiration rates were significantly increased, and microbial nitrogen fixation was significantly decreased. Taken together, our data suggest that iron is not a limiting factor of primary productivity in Red Sea corals. Rather, increased metabolic demands in response to iron enrichment, as evidenced by increased respiration rates, may reduce carbon (i.e., energy) availability in the coral holobiont, resulting in reduced microbial nitrogen fixation. This decrease in nitrogen supply in turn may exacerbate the limitation of other nutrients, creating a negative feedback loop. Thereby, our results highlight that the effects of iron enrichment appear to be strongly dependent on local environmental conditions and ultimately may depend on the availability of other nutrients.

  1. Study of biological compartments

    International Nuclear Information System (INIS)

    Rocha, A.F.G. da

    1976-01-01

    The several types of biological compartments are studied such as monocompartmental system, one-compartment balanced system irreversible fluxes, two closed compartment system, three compartment systems, catenary systems and mammilary systems [pt

  2. Applicability of a Supported Liquid Membrane in the Enrichment and Determination of Cadmium from Complex Aqueous Samples

    Directory of Open Access Journals (Sweden)

    Núria Pont

    2018-04-01

    Full Text Available A supported liquid membrane is developed for the separation of Cd from either high in salinity or acidity aqueous media. The membrane consisted of a durapore (polyvinylidene difluoride polymeric support impregnated with a 0.5 M Aliquat 336 solution in decaline. The effect of carrier concentration, organic solvent and feed and receiving solutions on the metal permeability is studied. This system allows the effective transport of trace levels of Cd through the formation of CdCl42−, which is the predominant species responsible for the extraction process, in both NaCl and HCl solutions. The supported liquid membrane system in a hollow fibre configuration allows the enrichment and separation of trace levels of Cd from spiked seawater samples, facilitating the analytical determination of this toxic metal.

  3. Accelerating the design of molecularly imprinted nanocomposite membranes modified by Au@polyaniline for selective enrichment and separation of ibuprofen

    Science.gov (United States)

    Wu, Xiuling; Wu, Yilin; Dong, Hongjun; Zhao, Juan; Wang, Chen; Zhou, Shi; Lu, Jian; Yan, Yongsheng; Li, He

    2018-01-01

    A novel system for harvesting molecularly imprinted nanocomposite membranes (MINcMs) with Au-modified polyaniline (Au@polyaniline) nanocomposite structure was developed for selective enrichment and separation of ibuprofen. This unique nanocomposite structure obviously enhanced the adsorption capacity, perm-selectivity performance, and regeneration ability of MINcMs. The as-prepared MINcMs showed outstanding adsorption capacity (22.02 mg g-1) of ibuprofen, which was four times higher than that of non-imprinted nanocomposite membranes (NINcMs). Furthermore, the selectivity factor of MINcMs for ibuprofen reached up to 4.67 and the perm-selectivity factor β was about 8.74, which indicated MINcMs had a good selective separation performance of ibuprofen. We envision that this novel synthesis method will open a new direction to manipulation of molecularly imprinted membrane materials and provide a simple yet convenient way to selective separation of ibuprofen.

  4. SCA-1 Labels a Subset of Estrogen-Responsive Bipotential Repopulating Cells within the CD24+ CD49fhi Mammary Stem Cell-Enriched Compartment

    Directory of Open Access Journals (Sweden)

    Genevieve V. Dall

    2017-02-01

    Full Text Available Estrogen stimulates breast development during puberty and mammary tumors in adulthood through estrogen receptor-α (ERα. These effects are proposed to occur via ERα+ luminal cells and not the mammary stem cells (MaSCs that are ERαneg. Since ERα+ luminal cells express stem cell antigen-1 (SCA-1, we sought to determine if SCA-1 could define an ERα+ subset of EpCAM+/CD24+/CD49fhi MaSCs. We show that the MaSC population has a distinct SCA-1+ population that is abundant in pre-pubertal mammary glands. The SCA-1+ MaSCs have less stem cell markers and less in vivo repopulating activity than their SCA-1neg counterparts. However, they express ERα and specifically enter the cell cycle at puberty. Using estrogen-deficient aromatase knockouts (ArKO, we showed that the SCA-1+ MaSC could be directly modulated by estrogen supplementation. Thus, SCA-1 enriches for an ERα+, estrogen-sensitive subpopulation within the CD24+/CD49fhi MaSC population that may be responsible for the hormonal sensitivity of the developing mammary gland.

  5. Palmitoylated claudin7 captured in glycolipid-enriched membrane microdomains promotes metastasis via associated transmembrane and cytosolic molecules

    OpenAIRE

    Thuma, Florian; Heiler, Sarah; Schn?lzer, Martina; Z?ller, Margot

    2016-01-01

    In epithelial cells claudin7 (cld7) is a major component of tight junctions, but is also recovered from glycolipid-enriched membrane microdomains (GEM). In tumor cells, too, cld7 exists in two stages. Only GEM-located cld7, which is palmitoylated, promotes metastasis. Searching for the underlying mechanism(s) revealed the following. The metastatic capacity of the rat pancreatic adenocarcinoma cell line ASML is lost by a knockdown (kd) of cld7 and is not regained by rescuing cld7 with a mutate...

  6. Graphene oxide enrichment of collagen membranes improves DPSCs differentiation and controls inflammation occurrence.

    Science.gov (United States)

    Radunovic, Milena; De Colli, Marianna; De Marco, Patrizia; Di Nisio, Chiara; Fontana, Antonella; Piattelli, Adriano; Cataldi, Amelia; Zara, Susi

    2017-08-01

    Collagen membranes are used in oral surgery for bone defects treatment acting as a barrier that does not allow the invasion of soft tissue into the growing bone. To improve biocompatibility collagen membranes were coated with graphene oxide (GO), a graphene derivative. The aim of this study was to investigate the biocompatibility of GO coated collagen membranes on human dental pulp stem cells (DPSCs) focusing on biomaterial cytotoxicity, ability to promote DPSCs differentiation process and to control inflammation event induction. DPSCs were cultured on uncoated membranes and on both 2 and 10 μg mL -1 GO coated membranes up to 28 days. Alamar blue and LDH cytotocicity assay, PGE2 ELISA assay, real time RT-PCR for RUNX2, BMP2, SP7, TNFα and COX2 genes expression were performed. Proliferation is higher on GO coated membranes at days 14 and 28. LDH assay evidences no cytotoxicity. BMP2 and RUNX2 expression is higher on coated membranes, BMP2 at early and RUNX2 and SP7 at late experimental times. PGE2 levels are lower on GO coated membranes at days 14 and 28, both TNFα and COX2 expression is significantly decreased when GO is applied. GO coated membranes are not toxic for DPSCs, induce a faster DPSCs differentiation into odontoblasts/osteoblasts and may represent good alternative to conventional membranes thus ensuring more efficient bone formation and improving the clinical performance. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2312-2320, 2017. © 2017 Wiley Periodicals, Inc.

  7. Enrichment of Thermophilic Syntrophic Anaerobic Glutamate-Degrading Consortia using a Dialysis Membrane Reactor

    NARCIS (Netherlands)

    Plugge, C.M.; Stams, A.J.M.

    2002-01-01

    A dialysis cultivation system was used to enrich slow-growing moderately thermophilic anaerobic bacteria at high cell densities. Bicarbonate buffered mineral salts medium with 5 mM glutamate as the sole carbon and energy source was used and the incubation temperature was 55 degrees C. The reactor

  8. Simultaneous enrichment of denitrifying anaerobic methane-oxidizing microorganisms and anammox bacteria in a hollow-fiber membrane biofilm reactor.

    Science.gov (United States)

    Ding, Zhao-Wei; Lu, Yong-Ze; Fu, Liang; Ding, Jing; Zeng, Raymond J

    2017-01-01

    In this study, the coculture system of denitrifying anaerobic methane oxidation (DAMO) microbes and anaerobic ammonium oxidation (anammox) bacteria was successfully enriched in a hollow-fiber membrane biofilm reactor (HfMBR) using freshwater sediment as the inoculum. The maximal removal rates of nitrate and ammonium were 78 mg N/L/day (131 mg N/m 2 /day) and 26 mg N/L/day (43 mg N/m 2 /day), respectively. Due to the high rate of methane mass transfer in HfMBR, the activity of DAMO archaea continued to increase during the enrichment period, indicating that HfMBR could be a powerful tool to enrich DAMO microorganisms. Effects of partial methane pressure, temperature, and pH on the cocultures were obvious. However, the microbial activity in HfMBR could be recovered quickly after the shock change of environmental factors. Furthermore, the result also found that DAMO bacteria likely had a stronger competitive advantage than anammox bacteria under the operating conditions in this study. High-throughput sequencing 16S rRNA genes illustrated that the dominant microbes were NC10, Euryarchaeota, Proteobacteria, Planctomycetes, and Chlorobi with relative abundance of 38.8, 26.2, 13.78, 6.2, and 3.6 %, respectively.

  9. Highly Efficient Single-Step Enrichment of Low Abundance Phosphopeptides from Plant Membrane Preparations

    Directory of Open Access Journals (Sweden)

    Xu Na Wu

    2017-09-01

    Full Text Available Mass spectrometry (MS-based large scale phosphoproteomics has facilitated the investigation of plant phosphorylation dynamics on a system-wide scale. However, generating large scale data sets for membrane phosphoproteins usually requires fractionation of samples and extended hands-on laboratory time. To overcome these limitations, we developed “ShortPhos,” an efficient and simple phosphoproteomics protocol optimized for research on plant membrane proteins. The optimized workflow allows fast and efficient identification and quantification of phosphopeptides, even from small amounts of starting plant materials. “ShortPhos” can produce label-free datasets with a high quantitative reproducibility. In addition, the “ShortPhos” protocol recovered more phosphorylation sites from membrane proteins, especially plasma membrane and vacuolar proteins, when compared to our previous workflow and other membrane-based data in the PhosPhAt 4.0 database. We applied “ShortPhos” to study kinase-substrate relationships within a nitrate-induction experiment on Arabidopsis roots. The “ShortPhos” identified significantly more known kinase-substrate relationships compared to previous phosphoproteomics workflows, producing new insights into nitrate-induced signaling pathways.

  10. The assembly of GM1 glycolipid- and cholesterol-enriched raft-like membrane microdomains is important for giardial encystation.

    Science.gov (United States)

    De Chatterjee, Atasi; Mendez, Tavis L; Roychowdhury, Sukla; Das, Siddhartha

    2015-05-01

    Although encystation (or cyst formation) is an important step of the life cycle of Giardia, the cellular events that trigger encystation are poorly understood. Because membrane microdomains are involved in inducing growth and differentiation in many eukaryotes, we wondered if these raft-like domains are assembled by this parasite and participate in the encystation process. Since the GM1 ganglioside is a major constituent of mammalian lipid rafts (LRs) and known to react with cholera toxin B (CTXB), we used Alexa Fluor-conjugated CTXB and GM1 antibodies to detect giardial LRs. Raft-like structures in trophozoites are located in the plasma membranes and on the periphery of ventral discs. In cysts, however, they are localized in the membranes beneath the cyst wall. Nystatin and filipin III, two cholesterol-binding agents, and oseltamivir (Tamiflu), a viral neuraminidase inhibitor, disassembled the microdomains, as evidenced by reduced staining of trophozoites with CTXB and GM1 antibodies. GM1- and cholesterol-enriched LRs were isolated from Giardia by density gradient centrifugation and found to be sensitive to nystatin and oseltamivir. The involvement of LRs in encystation could be supported by the observation that raft inhibitors interrupted the biogenesis of encystation-specific vesicles and cyst production. Furthermore, culturing of trophozoites in dialyzed medium containing fetal bovine serum (which is low in cholesterol) reduced raft assembly and encystation, which could be rescued by adding cholesterol from the outside. Our results suggest that Giardia is able to form GM1- and cholesterol-enriched lipid rafts and these raft domains are important for encystation. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  11. Nanoporous MoS2 monolayer as a promising membrane for purifying hydrogen and enriching methane

    Science.gov (United States)

    Zhang, Yadong; Meng, Zhaoshun; Shi, Qi; Gao, Haiqi; Liu, Yuzhen; Wang, Yunhui; Rao, Dewei; Deng, Kaiming; Lu, Ruifeng

    2017-09-01

    We present a theoretical prediction of a highly efficient membrane for hydrogen purification and natural gas upgrading, i.e. laminar MoS2 material with triangular sulfur-edged nanopores. We calculated from first principles the diffusion barriers of H2 and CO2 across monolayer MoS2 to be, respectively, 0.07 eV and 0.17 eV, which are low enough to warrant their great permeability. The permeance values for H2 and CO2 far exceed the industrially accepted standard. Meanwhile, such a porous MoS2 membrane shows excellent selectivity in terms of H2/CO, H2/N2, H2/CH4, and CO2/CH4 separation (>103, >  103, >  106, and  >  104, respectively) at room temperature. We expect that the findings in this work will expedite theoretical or experimental exploration on gas separation membranes based on transition metal dichalcogenides.

  12. Basic technology for {sup 6}Li enrichment using an ionic-liquid impregnated organic membrane

    Energy Technology Data Exchange (ETDEWEB)

    Hoshino, Tsuyoshi, E-mail: hoshino.tsuyoshi@jaea.go.jp [Blanket Irradiation and Analysis Group, Fusion Research and Development Directorate, Japan Atomic Energy Agency, 4002, Narita-cho, Oarai-machi, Higashi Ibaraki-gun, Ibaraki 311-1393 (Japan); Terai, Takayuki [The Institute of Engineering Innovation and Department of Nuclear Engineering and Management School of Engineering, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-8656 (Japan)

    2011-10-01

    The tritium needed as a fuel for fusion reactors is produced by the neutron capture reaction of lithium-6 ({sup 6}Li) in tritium breeding materials. However, natural Li contains only about 7.6 at.% {sup 6}Li. In this paper, a new lithium isotope separation technique using an ionic-liquid impregnated organic membrane is proposed. In order to separate and concentrate lithium isotopes, only lithium ions are able to move through the membrane by electrodialysis between the cathode and the anode in lithium solutions. Preliminary experiments of lithium isotope separation were conducted using this phenomenon. Organic membranes impregnated with TMPA-TFSI and PP13-TFSI as ionic liquids were prepared, and the relationship between the {sup 6}Li separation coefficient and the applied electrodialytic conditions was evaluated using them. The results showed that the {sup 6}Li isotope separation coefficient in this method (about 1.1-1.4) was larger than that in the mercury amalgam method (about 1.06).

  13. Ceramide-Enriched Membrane Domains in Red Blood Cells and the Mechanism ofSphingomyelinase-Induced Hot-Cold Hemolysis

    DEFF Research Database (Denmark)

    Montes, Ruth; Lopez, David; Sot, Jesus

    2008-01-01

    Hot-cold hemolysis is the phenomenon whereby red blood cells, preincubated at 37 °C in the presence of certain agents, undergo rapid hemolysis when transferred to 4 °C. The mechanism of this phenomenon is not understood. PlcHR2, a phospholipase C/sphingomyelinase from Pseudomonas aeruginosa......) but also in goat erythrocytes, which lack PC. However, in horse erythrocytes, with a large proportion of PC and almost no SM, hot-cold hemolysis induced by PlcHR2 is not observed. Fluorescence microscopy observations confirm the formation of ceramide-enriched domains as a result of PlcHR2 activity. After......-cold hemolysis. Differential scanning calorimetry of erytrocyte membranes treated with PlcHR2 demonstrates the presence of ceramide-rich domains that are rigid at 4 °C but fluid at 37 °C. Ceramidase treatment causes the disapperance of the calorimetric signal assigned to ceramide-rich domains. Finally...

  14. Dual-Compartment Inflatable Suitlock

    Science.gov (United States)

    Kennedy, Kriss J.; Guirgis, Peggy L.; Boyle, Robert M.

    2013-01-01

    There is a need for an improvement over current NASA Extravehicular Activity (EVA) technology. The technology must allow the capacity for quicker, more efficient egress/ingress, allow for shirtsleeve suit maintenance, be compact in transport, and be applicable to environments ranging from planetary surface (partial-g) to orbital or deep space zero-g environments. The technology must also be resistant to dust and other foreign contaminants that may be present on or around a planetary surface. The technology should be portable, and be capable of docking with a variety of habitats, ports, stations, vehicles, and other pressurized modules. The Dual-Compartment Inflatable Suitlock (DCIS) consists of three hard inline bulkheads, separating two cylindrical membrane-walled compartments. The Inner Bulkhead can be fitted with a variety of hatch types, docking flanges, and mating hardware, such as the Common Berthing Mechanism (CBM), for the purpose of mating with vehicles, habitats, and other pressurized modules. The Inner Bulkhead and Center Bulkhead function as the end walls of the Inner Compartment, which during operations, would stay pressurized, either matching the pressure of the habitat or acting as a lower-pressure transitional volume. The Inner Compartment contains donning/doffing fixtures and inner suit-port hatches. The Center Bulkhead has two integrated suit-ports along with a maintenance hatch. The Center Bulkhead and Outer Bulkhead function as the end walls of the Outer Compartment, which stays at vacuum during normal operations. This allows the crewmember to quickly don a suit, and egress the suitlock without waiting for the Outer Compartment to depressurize. The Outer Compartment can be pressurized infrequently for both nominal and off-nominal suit maintenance tasks, allowing shirtsleeve inspections and maintenance/repair of the environmental suits. The Outer Bulkhead has a pressure-assisted hatch door that stays open and stowed during EVA operations, but can

  15. Preparation of rat gastric heavy and light microsomal membranes enriched in (H+-K+)-ATPase using 2H2O and Percoll gradients

    International Nuclear Information System (INIS)

    Im, W.B.; Davis, J.P.; Blakeman, D.P.

    1985-01-01

    Gastric heavy microsomal membranes highly enriched in (H + -K + )-ATPase were obtained from cimetidine- or carbachol-treated rats through 2 H 2 O and Percoll gradient centrifugations. Both the resting (cimetidine-treated) and the stimulated (carbachol-treated) heavy membranes which presumably represent the apical membrane of gastric parietal cells were enriched with the polypeptides of 81,000 and 45,000 besides that of 93,000 representing (H + -K + )-ATPase. No apparent differences could be detected between the resting and the stimulated heavy membranes in their polypeptide profiles or their specific activity of (H + -K + )-ATPase. Nevertheless, the level of 86 RbCl uptake was greater in the stimulated than the resting heavy microsomal membrane vesicles. The light gastric microsomes which abound in intracellular tubulovesicles containing reserve (H + -K + )-ATPase as isolated from cimetidine-treated rats were similarly purified with respect to (H + -K + )-ATPase. The purified light gastric membranes were largely devoid of the polypeptides of 81,000 and 45,000 found in the heavy gastric membranes. These observations further support the current hypothesis that secretagogues bring about changes in the environment of (H + -K + )-ATPase and induce KCl permeability in the apical membrane of the parietal cells, although at present the authors have been unable to identify the polypeptide(s) responsible for the KCl pathway

  16. Undressing of Waddlia chondrophila to enrich its outer membrane proteins to develop a new species-specific ELISA

    Directory of Open Access Journals (Sweden)

    J. Lienard

    2014-01-01

    Full Text Available Waddlia chondrophila, an obligate intracellular bacterium of the Chlamydiales order, is considered as an agent of bovine abortion and a likely cause of miscarriage in humans. Its role in respiratory diseases was questioned after the detection of its DNA in clinical samples taken from patients suffering from pneumonia or bronchiolitis. To better define the role of Waddlia in both miscarriage and pneumonia, a tool allowing large-scale serological investigations of Waddlia seropositivity is needed. Therefore, enriched outer membrane proteins of W. chondrophila were used as antigens to develop a specific ELISA. After thorough analytical optimization, the ELISA was validated by comparison with micro-immunofluorescence and it showed a sensitivity above 85% with 100% specificity. The ELISA was subsequently applied to human sera to specify the role of W. chondrophila in pneumonia. Overall, 3.6% of children showed antibody reactivity against W. chondrophila but no significant difference was observed between children with and without pneumonia. Proteomic analyses were then performed using mass spectrometry, highlighting members of the outer membrane protein family as the dominant proteins. The major Waddlia putative immunogenic proteins were identified by immunoblot using positive and negative human sera. The new ELISA represents an efficient tool with high throughput applications. Although no association with pneumonia and Waddlia seropositivity was observed, this ELISA could be used to specify the role of W. chondrophila in miscarriage and in other diseases.

  17. A highly phosphorylated subpopulation of insulin-like growth factor II/mannose 6-phosphate receptors is concentrated in a clathrin-enriched plasma membrane fraction

    International Nuclear Information System (INIS)

    Corvera, S.; Folander, K.; Clairmont, K.B.; Czech, M.P.

    1988-01-01

    Insulin-like growth factor II (IGF-II)/mannose 6-phosphate (Man-6-P) receptors immunoprecipitated from purified plasma membranes of 32 P-labeled rat adipocytes are markedly heterogenous in their phosphorylation state. Approximately 80% of the plasma membrane receptors are solubilized in 1% (vol/vol) Triton X-100 and are phosphorylated on serine residues at a stoichiometry of ∼ 0.1-0.2 mol of phosphate per mol of receptor. In contrast, 15-20% of the receptors are Triton X-100-insoluble and are phosphorylated on serine and threonine residues at ∼ 4 or 5 mol of phosphate per mol of receptor. This Triton X-100-insoluble membrane subfraction contains only 5% of the total plasma membrane protein and yet contains all of the clathrin heavy chain associated with plasma membrane. Based on the relative yields of protein in the detergent-insoluble material, IGF-II/Man-6-P receptors are concentrated ∼ 3-fold in this clathrin-enriched subfraction. Taken together, these results indicate that insulin decreases the phosphorylation state of a highly phosphorylated subpopulation of IGF-II/Man-6-P receptors on the plasma membrane. In addition, insulin action may prevent the concentration of these receptors in a clathrin-enriched membrane subfraction

  18. TEMPERATURE DEPENDENT PHASE BEHAVIOR AND PROTEIN PARTITIONING IN GIANT PLASMA MEMBRANE VESICLES

    OpenAIRE

    Johnson, SA; Stinson, BM; Go, M; Carmona, LM; Reminick, JI; Fang, X; Baumgart, T

    2010-01-01

    Liquid-ordered (Lo) and liquid-disordered (Ld) phase coexistence has been suggested to partition the plasma membrane of biological cells into lateral compartments, allowing for enrichment or depletion of functionally relevant molecules. This dynamic partitioning might be involved in fine-tuning cellular signaling fidelity through coupling to the plasma membrane protein and lipid composition. In earlier work, giant plasma membrane vesicles, obtained by chemically induced blebbing from cultured...

  19. A review of reagents for fluorescence microscopy of cellular compartments and structures, Part III: reagents for actin, tubulin, cellular membranes, and whole cell and cytoplasm.

    Science.gov (United States)

    Kilgore, Jason A; Dolman, Nick J; Davidson, Michael W

    2014-01-02

    Non-antibody commercial fluorescent reagents for imaging of cytoskeletal structures have been limited primarily to tubulin and actin, with the main factor in choice based mainly on whether cells are live or fixed and permeabilized. A wider range of options exist for cell membrane dyes, and the choice of reagent primarily depends on the preferred localization in the cell (i.e., all membranes or only the plasma membrane) and usage (i.e., whether the protocol involves fixation and permeabilization). For whole-cell or cytoplasmic imaging, the choice of reagent is determined mostly by the length of time that the cells need to be visualized (hours or days) and by fixation status. Presented here is a discussion on choosing commercially available reagents for these cellular structures, with an emphasis on use for microscopic imaging, with a featured reagent for each structure, a recommended protocol, troubleshooting guide, and example image. Copyright © 2014 John Wiley & Sons, Inc.

  20. Arabidopsis dynamin-related protein 1E in sphingolipid-enriched plasma membrane domains is associated with the development of freezing tolerance.

    Science.gov (United States)

    Minami, Anzu; Tominaga, Yoko; Furuto, Akari; Kondo, Mariko; Kawamura, Yukio; Uemura, Matsuo

    2015-08-01

    The freezing tolerance of Arabidopsis thaliana is enhanced by cold acclimation, resulting in changes in the compositions and function of the plasma membrane. Here, we show that a dynamin-related protein 1E (DRP1E), which is thought to function in the vesicle trafficking pathway in cells, is related to an increase in freezing tolerance during cold acclimation. DRP1E accumulated in sphingolipid and sterol-enriched plasma membrane domains after cold acclimation. Analysis of drp1e mutants clearly showed that DRP1E is required for full development of freezing tolerance after cold acclimation. DRP1E fused with green fluorescent protein was visible as small foci that overlapped with fluorescent dye-labelled plasma membrane, providing evidence that DRP1E localizes non-uniformly in specific areas of the plasma membrane. These results suggest that DRP1E accumulates in sphingolipid and sterol-enriched plasma membrane domains and plays a role in freezing tolerance development during cold acclimation. © 2015 The Authors The Plant Journal © 2015 John Wiley & Sons Ltd.

  1. Sterol-induced Dislocation of 3-Hydroxy-3-methylglutaryl Coenzyme A Reductase from Endoplasmic Reticulum Membranes into the Cytosol through a Subcellular Compartment Resembling Lipid Droplets*

    Science.gov (United States)

    Hartman, Isamu Z.; Liu, Pingsheng; Zehmer, John K.; Luby-Phelps, Katherine; Jo, Youngah; Anderson, Richard G. W.; DeBose-Boyd, Russell A.

    2010-01-01

    Sterol-induced binding to Insigs in the endoplasmic reticulum (ER) allows for ubiquitination of 3-hydroxy-3-methylglutaryl coenzyme A reductase, the rate-limiting enzyme in cholesterol synthesis. This ubiquitination marks reductase for recognition by the ATPase VCP/p97, which mediates extraction and delivery of reductase from ER membranes to cytosolic 26 S proteasomes for degradation. Here, we report that reductase becomes dislocated from ER membranes into the cytosol of sterol-treated cells. This dislocation exhibits an absolute requirement for the actions of Insigs and VCP/p97. Reductase also appears in a buoyant fraction of sterol-treated cells that co-purifies with lipid droplets, cytosolic organelles traditionally regarded as storage depots for neutral lipids such as triglycerides and cholesteryl esters. Genetic, biochemical, and localization studies suggest a model in which reductase is dislodged into the cytosol from an ER subdomain closely associated with lipid droplets. PMID:20406816

  2. Anionic lipids and the maintenance of membrane electrostatics in eukaryotes.

    Science.gov (United States)

    Platre, Matthieu Pierre; Jaillais, Yvon

    2017-02-01

    A wide range of signaling processes occurs at the cell surface through the reversible association of proteins from the cytosol to the plasma membrane. Some low abundant lipids are enriched at the membrane of specific compartments and thereby contribute to the identity of cell organelles by acting as biochemical landmarks. Lipids also influence membrane biophysical properties, which emerge as an important feature in specifying cellular territories. Such parameters are crucial for signal transduction and include lipid packing, membrane curvature and electrostatics. In particular, membrane electrostatics specifies the identity of the plasma membrane inner leaflet. Membrane surface charges are carried by anionic phospholipids, however the exact nature of the lipid(s) that powers the plasma membrane electrostatic field varies among eukaryotes and has been hotly debated during the last decade. Herein, we discuss the role of anionic lipids in setting up plasma membrane electrostatics and we compare similarities and differences that were found in different eukaryotic cells.

  3. ACUTE COMPARTMENT SYNDROME

    African Journals Online (AJOL)

    muscle destruction, muscle fibrosis, contractures and permanent disability and at worst case scenario of amputation (3,4). As reported by Frink et al (3) on their study on acute compartment syndrome it can occur even when there is no fracture. Also general surgeons have reported acute compartment syndrome.

  4. Seawater-driven forward osmosis for enriching nitrogen and phosphorous in treated municipal wastewater: effect of membrane properties and feed solution chemistry.

    Science.gov (United States)

    Xue, Wenchao; Tobino, Tomohiro; Nakajima, Fumiyuki; Yamamoto, Kazuo

    2015-02-01

    Seawater-driven forward osmosis (FO) is considered to be a novel strategy to concentrate nutrients in treated municipal wastewater for further recovery as well as simultaneous discharge of highly purified wastewater into the sea with low cost. As a preliminary test, the performance of FO membranes in concentrating nutrients was investigated by both batch experiments and model simulation approaches. With synthetic seawater as the draw solution, the dissolved organic carbon, phosphate, and ammonia in the effluent from a membrane bioreactor (MBR) treating municipal wastewater were 2.3-fold, 2.3-fold, and 2.1-fold, respectively, concentrated by the FO process with approximately 57% of water reduction. Most of the dissolved components, including trace metals in the MBR effluent, were highly retained (>80%) in the feed side, indicating high water quality of permeate to be discharged. The effect of membrane properties on the nutrient enrichment performance was investigated by comparing three types of FO membranes. Interestingly, a polyamide membrane possessing a high negative charge demonstrated a poor capability of retaining ammonia, which was hypothesized because of an ion exchange-like mechanism across the membrane prompted by the high ionic concentration of the draw solution. A feed solution pH of 7 was demonstrated to be an optimum condition for improving the overall retention of nutrients, especially for ammonia because of the pH-dependent speciation of ammonia/ammonium forms. The modeling results showed that higher than 10-fold concentrations of ammonia and phosphate are achievable by seawater-driven FO with a draw solution to feed solution volume ratio of 2:1. The enriched municipal wastewater contains nitrogen and phosphorous concentrations comparable with typical animal wastewater and anaerobic digestion effluent, which are used for direct nutrient recovery. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Interpretation of the measurement of ions fluxes through a biological membrane with a cellular compartment: example of the movements of sodium through the skin of frogs; Interpretation de la mesure des flux d'ions a travers une membrane biologique comportant un ''compartiment'' cellulaire; exemple des mouvements de sodium a travers la peau de grenouille

    Energy Technology Data Exchange (ETDEWEB)

    Morel, F [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1959-07-01

    Two-way ion fluxes which can be measured in vitro through a living epithelial membrane (such as frog skin) by the indicator method take place across the cells which behave like an intermediate ionic 'compartment'. Two membranes and four fluxes have thus to be considered. Measurements in vitro of the total sodium fluxes as a function of the sodium concentration in the medium in contact with the external face of the skin have been interpreted in this spirit. Making use of certain hypotheses, the permeability coefficients for sodium of the two cellular membranes, the four sodium fluxes, the intracellular sodium concentration and the membrane potentials have been calculated for each value of the sodium concentration in the external medium. (author) [French] Les flux ioniques bidirectionnels que l'on peut mesurer in vitro a travers une membrane epitheliale vivante (comme la peau de grenouille) a l'aide de la methode des indicateurs, s'effectuent a travers les cellules qui se comportent comme un 'compartiment' ionique intermediaire. On doit donc considerer deux membranes et quatre flux. Des mesures in vitro des flux totaux de sodium en fonction de la concentration du sodium dans le milieu baignant la face externe de la peau ont ete interpretees dans cette perspective. Moyennant certaines hypotheses, les coefficients de permeabilite pour le sodium des deux membranes cellulaires, les quatre flux de sodium ainsi que la concentration du sodium intracellulaire et les potentiels de membrane ont pu etre calcules pour chaque valeur de la concentration du sodium dans le milieu externe. (auteur)

  6. Abdominal Compartment Syndrome

    Directory of Open Access Journals (Sweden)

    Pınar Zeyneloğlu

    2015-04-01

    Full Text Available Intraabdominal hypertension and Abdominal compartment syndrome are causes of morbidity and mortality in critical care patients. Timely diagnosis and treatment may improve organ functions. Intra-abdominal pressure monitoring is vital during evaluation of the patients and in the management algorithms. The incidence, definition and risk factors, clinical presentation, diagnosis and management of intraabdominal hypertension and Abdominal compartment syndrome were reviewed here.

  7. Gag induces the coalescence of clustered lipid rafts and tetraspanin-enriched microdomains at HIV-1 assembly sites on the plasma membrane.

    Science.gov (United States)

    Hogue, Ian B; Grover, Jonathan R; Soheilian, Ferri; Nagashima, Kunio; Ono, Akira

    2011-10-01

    The HIV-1 structural protein Gag associates with two types of plasma membrane microdomains, lipid rafts and tetraspanin-enriched microdomains (TEMs), both of which have been proposed to be platforms for HIV-1 assembly. However, a variety of studies have demonstrated that lipid rafts and TEMs are distinct microdomains in the absence of HIV-1 infection. To measure the impact of Gag on microdomain behaviors, we took advantage of two assays: an antibody-mediated copatching assay and a Förster resonance energy transfer (FRET) assay that measures the clustering of microdomain markers in live cells without antibody-mediated patching. We found that lipid rafts and TEMs copatched and clustered to a greater extent in the presence of membrane-bound Gag in both assays, suggesting that Gag induces the coalescence of lipid rafts and TEMs. Substitutions in membrane binding motifs of Gag revealed that, while Gag membrane binding is necessary to induce coalescence of lipid rafts and TEMs, either acylation of Gag or binding of phosphatidylinositol-(4,5)-bisphosphate is sufficient. Finally, a Gag derivative that is defective in inducing membrane curvature appeared less able to induce lipid raft and TEM coalescence. A higher-resolution analysis of assembly sites by correlative fluorescence and scanning electron microscopy showed that coalescence of clustered lipid rafts and TEMs occurs predominantly at completed cell surface virus-like particles, whereas a transmembrane raft marker protein appeared to associate with punctate Gag fluorescence even in the absence of cell surface particles. Together, these results suggest that different membrane microdomain components are recruited in a stepwise manner during assembly.

  8. Gag Induces the Coalescence of Clustered Lipid Rafts and Tetraspanin-Enriched Microdomains at HIV-1 Assembly Sites on the Plasma Membrane

    Science.gov (United States)

    Hogue, Ian B.; Grover, Jonathan R.; Soheilian, Ferri; Nagashima, Kunio; Ono, Akira

    2011-01-01

    The HIV-1 structural protein Gag associates with two types of plasma membrane microdomains, lipid rafts and tetraspanin-enriched microdomains (TEMs), both of which have been proposed to be platforms for HIV-1 assembly. However, a variety of studies have demonstrated that lipid rafts and TEMs are distinct microdomains in the absence of HIV-1 infection. To measure the impact of Gag on microdomain behaviors, we took advantage of two assays: an antibody-mediated copatching assay and a Förster resonance energy transfer (FRET) assay that measures the clustering of microdomain markers in live cells without antibody-mediated patching. We found that lipid rafts and TEMs copatched and clustered to a greater extent in the presence of membrane-bound Gag in both assays, suggesting that Gag induces the coalescence of lipid rafts and TEMs. Substitutions in membrane binding motifs of Gag revealed that, while Gag membrane binding is necessary to induce coalescence of lipid rafts and TEMs, either acylation of Gag or binding of phosphatidylinositol-(4,5)-bisphosphate is sufficient. Finally, a Gag derivative that is defective in inducing membrane curvature appeared less able to induce lipid raft and TEM coalescence. A higher-resolution analysis of assembly sites by correlative fluorescence and scanning electron microscopy showed that coalescence of clustered lipid rafts and TEMs occurs predominately at completed cell surface virus-like particles, whereas a transmembrane raft marker protein appeared to associate with punctate Gag fluorescence even in the absence of cell surface particles. Together, these results suggest that different membrane microdomain components are recruited in a stepwise manner during assembly. PMID:21813604

  9. Effects of n-3 and n-6 polyunsaturated fatty acid-enriched diets on lipid metabolism in periportal and pericentral compartments of female rat liver lobules and the consequences for cell proliferation after partial hepatectomy

    NARCIS (Netherlands)

    van Noorden, C. J.

    1995-01-01

    The effects of a low fat diet or diets enriched with either n-6 or n-3 polyunsaturated fatty acids (safflower or fish oil, respectively) on lipid metabolism in periportal and pericentral zones of female rat liver lobules were investigated in relation with cell proliferation after partial

  10. Isolation and characterization of the plasma membrane from the yeast Pichia pastoris.

    Science.gov (United States)

    Grillitsch, Karlheinz; Tarazona, Pablo; Klug, Lisa; Wriessnegger, Tamara; Zellnig, Günther; Leitner, Erich; Feussner, Ivo; Daum, Günther

    2014-07-01

    Despite similarities of cellular membranes in all eukaryotes, every compartment displays characteristic and often unique features which are important for the functions of the specific organelles. In the present study, we biochemically characterized the plasma membrane of the methylotrophic yeast Pichia pastoris with emphasis on the lipids which form the matrix of this compartment. Prerequisite for this effort was the design of a standardized and reliable isolation protocol of the plasma membrane at high purity. Analysis of isolated plasma membrane samples from P. pastoris revealed an increase of phosphatidylserine and a decrease of phosphatidylcholine compared to bulk membranes. The amount of saturated fatty acids in the plasma membrane was higher than in total cell extracts. Ergosterol, the final product of the yeast sterol biosynthetic pathway, was found to be enriched in plasma membrane fractions, although markedly lower than in Saccharomyces cerevisiae. A further characteristic feature of the plasma membrane from P. pastoris was the enrichment of inositol phosphorylceramides over neutral sphingolipids, which accumulated in internal membranes. The detailed analysis of the P. pastoris plasma membrane is discussed in the light of cell biological features of this microorganism especially as a microbial cell factory for heterologous protein production. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Catalytic combustion of the retentate gas from a CO2/H2 separation membrane reactor for further CO2 enrichment and energy recovery

    International Nuclear Information System (INIS)

    Hwang, Kyung-Ran; Park, Jin-Woo; Lee, Sung-Wook; Hong, Sungkook; Lee, Chun-Boo; Oh, Duck-Kyu; Jin, Min-Ho; Lee, Dong-Wook; Park, Jong-Soo

    2015-01-01

    The CCR (catalytic combustion reaction) of the retentate gas, consisting of 90% CO 2 and 10% H 2 obtained from a CO 2 /H 2 separation membrane reactor, was investigated using a porous Ni metal catalyst in order to recover energy and further enrich CO 2 . A disc-shaped porous Ni metal catalyst, namely Al[0.1]/Ni, was prepared by a simple method and a compact MCR (micro-channel reactor) equipped with a catalyst plate was designed for the CCR. CO 2 and H 2 concentrations of 98.68% and 0.46%, respectively, were achieved at an operating temperature of 400 °C, GHSV (gas-hourly space velocity) of 50,000 h −1 and a H 2 /O 2 ratio (R/O) of 2 in the unit module. In the case of the MCR, a sheet of the Ni metal catalyst was easily installed along with the other metal plates and the concentration of CO 2 in the retentate gas increased up to 96.7%. The differences in temperatures measured before and after the CCR were 31 °C at the product outlet and 19 °C at the N 2 outlet in the MCR. The disc-shaped porous metal catalyst and MCR configuration used in this study exhibit potential advantages, such as high thermal transfer resulting in improved energy recovery rate, simple catalyst preparation, and easy installation of the catalyst in the MCR. - Highlights: • The catalytic combustion of a retentate gas obtained from the H 2 /CO 2 separation membrane. • A disc-shaped porous nickel metal catalyst and a micro-channel reactor for catalytic hydrogen combustion. • CO 2 enrichment up to 98.68% at 400 °C, 50,000 h −1 and H 2 /O 2 ratio of 2.

  12. Plasma membrane associated membranes (PAM) from Jurkat cells contain STIM1 protein is PAM involved in the capacitative calcium entry?

    Science.gov (United States)

    Kozieł, Katarzyna; Lebiedzinska, Magdalena; Szabadkai, Gyorgy; Onopiuk, Marta; Brutkowski, Wojciech; Wierzbicka, Katarzyna; Wilczyński, Grzegorz; Pinton, Paolo; Duszyński, Jerzy; Zabłocki, Krzysztof; Wieckowski, Mariusz R

    2009-12-01

    A proper cooperation between the plasma membrane, the endoplasmic reticulum and the mitochondria seems to be essential for numerous cellular processes involved in Ca(2+) signalling and maintenance of Ca(2+) homeostasis. A presence of microsomal and mitochondrial proteins together with those characteristic for the plasma membrane in the fraction of the plasma membrane associated membranes (PAM) indicates a formation of stabile interactions between these three structures. We isolated the plasma membrane associated membranes from Jurkat cells and found its significant enrichment in the plasma membrane markers including plasma membrane Ca(2+)-ATPase, Na(+), K(+)-ATPase and CD3 as well as sarco/endoplasmic reticulum Ca(2+) ATPase as a marker of the endoplasmic reticulum membranes. In addition, two proteins involved in the store-operated Ca(2+) entry, Orai1 located in the plasma membrane and an endoplasmic reticulum protein STIM1 were found in this fraction. Furthermore, we observed a rearrangement of STIM1-containing protein complexes isolated from Jurkat cells undergoing stimulation by thapsigargin. We suggest that the inter-membrane compartment composed of the plasma membrane and the endoplasmic reticulum, and isolated as a stabile plasma membrane associated membranes fraction, might be involved in the store-operated Ca(2+) entry, and their formation and rebuilding have an important regulatory role in cellular Ca(2+) homeostasis.

  13. Effects of Glucomannan-Enriched, Aronia Juice-Based Supplement on Cellular Antioxidant Enzymes and Membrane Lipid Status in Subjects with Abdominal Obesity

    Directory of Open Access Journals (Sweden)

    Nevena Kardum

    2014-01-01

    Full Text Available The aim of this study was to analyze the effects of a 4-week-long consumption of glucomannan-enriched, aronia juice-based supplement on anthropometric parameters, membrane fatty acid profile, and status of antioxidant enzymes in erythrocytes obtained from postmenopausal women with abdominal obesity. Twenty women aged 45–65 with a mean body mass index (BMI of 36.1 ± 4.4 kg/m2 and waist circumference of 104.8 ± 10.1 cm were enrolled. Participants were instructed to consume 100 mL of supplement per day as part of their regular diet. A significant increase in the content of n-3 (P<0.05 polyunsaturated fatty acids in membrane phospholipids was observed, with a marked increase in the level of docosahexaenoic fatty acid (P<0.05. Accordingly, a decrease in the n-6 and n-3 fatty acids ratio was observed (P<0.05. The observed effects were accompanied with an increase in glutathione peroxidase activity (P<0.05. Values for BMI (P<0.001, waist circumference (P<0.001, and systolic blood pressure (P<0.05 were significantly lower after the intervention. The obtained results indicate a positive impact of tested supplement on cellular oxidative damage, blood pressure, and anthropometric indices of obesity.

  14. Overexpression of MicA induces production of OmpC-enriched outer membrane vesicles that protect against Salmonella challenge.

    Science.gov (United States)

    Choi, Hyun-Il; Kim, Moonjeong; Jeon, Jinseong; Han, Jin Kwan; Kim, Kwang-Sun

    2017-08-26

    Outer membrane vesicles (OMVs) derived from bacteria are promising candidates for subunit vaccines. Stresses that modulate the composition of outer membrane proteins (OMPs) are important for OMV synthesis. Small RNAs (sRNAs) expressed in response to stress regulate OMPs, although the mechanism underlying sRNA-mediated OMV biogenesis and its utility for developing vaccine platforms remains to be elucidated. Here, we characterized the role of a sRNA, MicA, which regulates OmpA, a major OMP involved in both production of OMVs and reactive immunity against Salmonella challenge. A Salmonella strain overexpressing MicA generated more OMVs than a control strain. In addition, OmpC was the major component of MicA-derived OMV proteins. MicA-derived OMVs induced Th1- and Th17-type immune responses in vitro and reduced Salmonella-mediated lethality in a mouse model. Thus, OmpA-regulatory sRNA-derived OMVs may facilitate production of Salmonella-protective vaccines. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Sensitive determination of trace mercury by UV-visible diffuse reflectance spectroscopy after complexation and membrane filtration-enrichment.

    Science.gov (United States)

    Yin, Changhai; Iqbal, Jibran; Hu, Huilian; Liu, Bingxiang; Zhang, Lei; Zhu, Bilin; Du, Yiping

    2012-09-30

    A simple, sensitive and selective solid phase reflectometry method is proposed for the determination of trace mercury in aqueous samples. The complexation reagent dithizone was firstly injected into the properly buffered solution with vigorous stirring, which started a simultaneous formation of nanoparticles suspension of dithizone and its complexation reaction with the mercury(II) ions to make Hg-dithizone nanoparticles. After a definite time, the mixture was filtered with membrane, and then quantified directly on the surface of the membrane by using integrating sphere accessory of the UV-visible spectrophotometer. The quantitative analysis was carried out at a wavelength of 485 nm since it yielded the largest difference in diffuse reflectance spectra before and after reaction with mercury(II).A good linear correlation in the range of 0.2-4.0 μg/L with a squared correlation coefficient (R(2)) of 0.9944 and a detection limit of 0.12 μg/L were obtained. The accuracy of the method was evaluated by the analysis of spiked mercury(II) concentrations determined using this method along with those determined by the atomic fluorescence mercury vapourmeter and the results obtained were in good agreement. The proposed method was applied to the determination of mercury in tap water and river water samples with the recovery in an acceptable range (95.7-105.3%). Copyright © 2012 Elsevier B.V. All rights reserved.

  16. Compartment syndrome without pain!

    LENUS (Irish Health Repository)

    O'Sullivan, M J

    2012-02-03

    We report the case of a young male patient who underwent intra-medullary nailing for a closed, displaced mid-shaft fracture of tibia and fibula. He was commenced on patient controlled analgesia post-operatively. A diagnosis of compartment syndrome in the patient\\'s leg was delayed because he did not exhibit a pain response. This ultimately resulted in a below-knee amputation of the patient\\'s leg. We caution against the use of patient controlled analgesia in any traumatised limb distal to the hip or the shoulder.

  17. [Determination of Trace Lead in Water by UV-Visible Diffuse Reflectance Spectroscopy Combined with Surfactant and Membrane Filtration-Enrichment].

    Science.gov (United States)

    Zhang, Xiao-fang; Zhu, Bi-lin; Li, Wei; Wang, Lei; Zhang, Lei; Wu, Ting; Du, Yi-ping

    2015-07-01

    In this paper, a method of determination of trace lead in water by UV-Visible diffuse reflectance spectroscopy combined with surfactant and membrane filtration enrichment was proposed. In the NH3 x H2O-NH4Cl buffer solution with pH 8.5, the lead(II) ion would react with dithizone to form the red complex under vigorous stirring, which is hydrophobic and can be enriched by the mixed cellulose ester membrane. In addition, the nonionic surfactant Polyoxyethylene lauryl ether (Brij-30) was added into the solution to improve the enrichment efficiency, then visible diffuse reflectance spectra of the membrane were measured directly after the membrane were naturally dried. We also optimized the reaction conditions which may affect the complexation reaction process, such as type of surfactants, the concentration of the surfactant, the reaction acidity, the concentration of dithizone as well as the reaction time. The research results show that under the optimum conditions, a good linear correlation between absorbance at 485 nm and concentration of lead in the range of 5.0-100.0 microg x L(-1) was obtained with a squared correlation coefficient (R2) of 0.9906, and the detection limit was estimated accordingly to be 2.88 microg x L(-1). To determine real water sample, the interference from some potential coexisting ions was also studied at the optimal conditions when the concentration of lead (II) ion standard solution was fixed to 20 microg x L(-1). The results indicate that the following ions cannot interfere in the determination of lead with the proposed method: 500 times of the K+, Na+, Ca2+, Mg2+, NH4+, NO3-, Cl-, CH3COO-, SO4(2-); 10 times of the Al3+ (using 10% NaF as a masking reagent to avoid the interference); 10 times of the Fe3+ (using 10% NaF and 10% sodium potassium tartrate as masking reagents); 10 times of Hg2+ or Zn2+ (using 10% NaSCN and 10% potassium sodium tartrate as masking reagents); the same amount of Cd2+, Cu2+. The proposed method was applied to the

  18. Chalcone inhibitors of the NorA efflux pump in Staphylococcus aureus whole cells and enriched everted membrane vesicles.

    Science.gov (United States)

    Holler, Jes Gitz; Slotved, Hans-Christian; Mølgaard, Per; Olsen, Carl Erik; Christensen, Søren Brøgger

    2012-07-15

    A library of 117 chalcones was screened for efflux pump inhibitory (EPI) activity against NorA mediated ethidium bromide efflux. Five of the chalcones (5-7, 9, and 10) were active and two chalcones (9 and 10) were equipotent to reserpine with IC(50)-values of 9.0 and 7.7 μM, respectively. Twenty chalcones were subsequently proved to be inhibitors of the NorA efflux pump in everted membrane vesicles. Compounds 5, 7, and 9 synergistically increased the effect of ciprofloxacin on Staphylococcus aureus. Our results suggest that chalcones might be developed into drugs for overcoming multidrug resistance based on efflux transporters of microorganisms. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Kinetic imaging of NPC1L1 and sterol trafficking between plasma membrane and recycling endosomes in hepatoma cells

    DEFF Research Database (Denmark)

    Hartwig Petersen, Nicole; Færgeman, Nils J; Yu, Liqing

    2008-01-01

    fluorescent protein (NPC1L1-EGFP) and cholesterol analogues in hepatoma cells. At steady state about 42% of NPC1L1 resided in the transferrin (Tf) positive, sterol enriched endocytic recycling compartment (ERC), while time-lapse microscopy demonstrated NPC1L1 traffic between plasma membrane and ERC...... the ERC to the plasma membrane. NPC1L1-EGFP facilitated transport of fluorescent sterols from the plasma membrane to the ERC. Insulin induced translocation of vesicles containing NPC1L1 and fluorescent sterol from the ERC to the cell membrane. Upon polarization of hepatoma cells NPC1L1 resided almost...... exclusively in the canalicular membrane, where the protein is highly mobile. Our study demonstrates dynamic trafficking of NPC1L1 between cell surface and intracellular compartments and suggests that this transport is involved in NPC1L1 mediated cellular sterol uptake....

  20. Modeling of compartment fire

    International Nuclear Information System (INIS)

    Sathiah, P.; Siccama, A.; Visser, D.; Komen, E.

    2011-01-01

    Fire accident in a containment is a serious threat to nuclear reactors. Fire can cause substantial loss to life and property. The risk posed by fire can also exceed the risk from internal events within a nuclear reactor. Numerous research efforts have been performed to understand and analyze the phenomenon of fire in nuclear reactor and its consequences. Modeling of fire is an important subject in the field of fire safety engineering. Two approaches which are commonly used in fire modeling are zonal modeling and field modeling. The objective of this work is to compare zonal and field modeling approach against a pool fired experiment performed in a well-confined compartment. Numerical simulations were performed against experiments, which were conducted within PRISME program under the framework of OECD. In these experiments, effects of ventilation flow rate on heat release rate in a confined and mechanically ventilated compartment is investigated. Time dependent changes in gas temperature and oxygen mass fraction were measured. The trends obtained by numerical simulation performed using zonal model and field model compares well with experiments. Further validation is needed before this code can be used for fire safety analyses. (author)

  1. Kidney compartment model

    International Nuclear Information System (INIS)

    Gullberg, G.T.

    1976-09-01

    A multiparameter kidney compartment model which quantitates the amount of iodohippurate concentration as a function of time in the blood, tissue, kidneys and bladder is developed from a system of differential equations which represent first order kinetics. The kinetic data are obtained using a gamma camera and an HP5407 computer system which allows one to delineate areas of interest for the blood and tissue, kidneys, and bladder thus separating the data into four data sets. The estimated tubular transit times have a high ratio of the signal to the variance whereas the estimates of the amount of iodohippurate in the blood, tissue and kidneys have a low ratio of the signal to the variance. Application of this model to patient data requires better statistics than available with conventional 131 I-hippurate doses; thus a true test of the efficacy awaits availability of 123 I-hippurate

  2. A novel membrane inlet mass spectrometer method to measure ¹⁵NH4₄⁺ for isotope-enrichment experiments in aquatic ecosystems.

    Science.gov (United States)

    Yin, Guoyu; Hou, Lijun; Liu, Min; Liu, Zhanfei; Gardner, Wayne S

    2014-08-19

    Nitrogen (N) pollution in aquatic ecosystems has attracted much attention over the past decades, but the dynamics of this bioreactive element are difficult to measure in aquatic oxygen-transition environments. Nitrogen-transformation experiments often require measurement of (15)N-ammonium ((15)NH4(+)) ratios in small-volume (15)N-enriched samples. Published methods to determine N isotope ratios of dissolved ammonium require large samples and/or costly equipment and effort. We present a novel ("OX/MIMS") method to determine N isotope ratios for (15)NH4(+) in experimental waters previously enriched with (15)N compounds. Dissolved reduced (15)N (dominated by (15)NH4(+)) is oxidized with hypobromite iodine to nitrogen gas ((29)N2 and/or (30)N2) and analyzed by membrane inlet mass spectrometry (MIMS) to quantify (15)NH4(+) concentrations. The N isotope ratios, obtained by comparing the (15)NH4(+) to total ammonium (via autoanalyzer) concentrations, are compared to the ratios of prepared standards. The OX/MIMS method requires only small sample volumes of water (ca. 12 mL) or sediment slurries and is rapid, convenient, accurate, and precise (R(2) = 0.9994, p < 0.0001) over a range of salinities and (15)N/(14)N ratios. It can provide data needed to quantify rates of ammonium regeneration, potential ammonium uptake, and dissimilatory nitrate reduction to ammonium (DNRA). Isotope ratio results agreed closely (R = 0.998, P = 0.001) with those determined independently by isotope ratio mass spectrometry for DNRA measurements or by ammonium isotope retention time shift liquid chromatography for water-column N-cycling experiments. Application of OX/MIMS should simplify experimental approaches and improve understanding of N-cycling rates and fate in a variety of freshwater and marine environments.

  3. Environmental enrichment choices of shelter cats.

    Science.gov (United States)

    Ellis, J J; Stryhn, H; Spears, J; Cockram, M S

    2017-08-01

    Choices made by cats between different types of environmental enrichment may help shelters to prioritize how to most effectively enrich cat housing, especially when limited by space or funds. This study investigates the environmental enrichment use of cats in a choice test. Twenty-six shelter cats were kept singularly in choice chambers for 10days. Each chamber had a central area and four centrally-linked compartments containing different types of environmental enrichment: 1) an empty control, 2) a prey-simulating toy, 3) a perching opportunity, and 4) a hiding opportunity. Cat movement between compartments was quantitatively recorded using a data-logger. Enriched compartments were visited significantly more frequently during the light period than during the dark period. Cats spent a significantly greater percentage of time in the hiding compartment (median=55%, IQR=46) than in the toy compartment (median=2%, IQR=9), or in the empty control compartment (median=4%, IQR=4). These results provide additional evidence to support the value of a hiding box to cats housed in a novel environment, in that they choose hiding relative to other types of environmental enrichment. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Uranium enrichment. Enrichment processes

    International Nuclear Information System (INIS)

    Alexandre, M.; Quaegebeur, J.P.

    2009-01-01

    Despite the remarkable progresses made in the diversity and the efficiency of the different uranium enrichment processes, only two industrial processes remain today which satisfy all of enriched uranium needs: the gaseous diffusion and the centrifugation. This article describes both processes and some others still at the demonstration or at the laboratory stage of development: 1 - general considerations; 2 - gaseous diffusion: physical principles, implementation, utilisation in the world; 3 - centrifugation: principles, elementary separation factor, flows inside a centrifuge, modeling of separation efficiencies, mechanical design, types of industrial centrifuges, realisation of cascades, main characteristics of the centrifugation process; 4 - aerodynamic processes: vortex process, nozzle process; 5 - chemical exchange separation processes: Japanese ASAHI process, French CHEMEX process; 6 - laser-based processes: SILVA process, SILMO process; 7 - electromagnetic and ionic processes: mass spectrometer and calutron, ion cyclotron resonance, rotating plasmas; 8 - thermal diffusion; 9 - conclusion. (J.S.)

  5. Double-compartment wrist arthrography

    International Nuclear Information System (INIS)

    Quinn, S.F.; Pittman, C.; Belsole, R.; Greene, T.L.; Rayhack, J.; Clark, R.A.; King, P.S.

    1987-01-01

    Seventy patients with clinical wrist problems were studied with double-compartment wrist arthrography. Midcarpal and radiocarpal compartment arthrograms were obtained in all patients. Digital subtraction technique was used to subtract out contrast from the first compartmental injection. Digital technique also allowed a dynamic record of each injection, which helped determine sites of intercompartmental communication. Postarthrography exercises recorded on videotape were performed after each injection. There were 34 normal studies. Abnormalities in the other 36 patients included: scapholunate communication (n = 9), lunatotriquetral communication (n = 6), communication with tendon sheaths (n = 4), communication with distal radioulnar compartment (n = 14), abnormal synovium process (n = 9), and communication through the radial or ulnar collateral ligament (n = 3). Double-compartment wrist arthrography may provide additional information for complex problems of the wrist

  6. Free-Flow Electrophoresis of Plasma Membrane Vesicles Enriched by Two-Phase Partitioning Enhances the Quality of the Proteome from Arabidopsis Seedlings.

    Science.gov (United States)

    de Michele, Roberto; McFarlane, Heather E; Parsons, Harriet T; Meents, Miranda J; Lao, Jeemeng; González Fernández-Niño, Susana M; Petzold, Christopher J; Frommer, Wolf B; Samuels, A Lacey; Heazlewood, Joshua L

    2016-03-04

    The plant plasma membrane is the interface between the cell and its environment undertaking a range of important functions related to transport, signaling, cell wall biosynthesis, and secretion. Multiple proteomic studies have attempted to capture the diversity of proteins in the plasma membrane using biochemical fractionation techniques. In this study, two-phase partitioning was combined with free-flow electrophoresis to produce a population of highly purified plasma membrane vesicles that were subsequently characterized by tandem mass spectroscopy. This combined high-quality plasma membrane isolation technique produced a reproducible proteomic library of over 1000 proteins with an extended dynamic range including plasma membrane-associated proteins. The approach enabled the detection of a number of putative plasma membrane proteins not previously identified by other studies, including peripheral membrane proteins. Utilizing multiple data sources, we developed a PM-confidence score to provide a value indicating association to the plasma membrane. This study highlights over 700 proteins that, while seemingly abundant at the plasma membrane, are mostly unstudied. To validate this data set, we selected 14 candidates and transiently localized 13 to the plasma membrane using a fluorescent tag. Given the importance of the plasma membrane, this data set provides a valuable tool to further investigate important proteins. The mass spectrometry data are available via ProteomeXchange, identifier PXD001795.

  7. Free-flow electrophoresis of plasma membrane vesicles enriched by two-phase partitioning enhances the quality of the proteome from Arabidopsis seedlings

    DEFF Research Database (Denmark)

    de Michele, Roberto; McFarlane, Heather E; Parsons, Harriet Tempé

    2016-01-01

    The plant plasma membrane is the interface between the cell and its environment undertaking a range of important functions related to transport, signaling, cell wall biosynthesis, and secretion. Multiple proteomic studies have attempted to capture the diversity of proteins in the plasma membrane...... using biochemical fractionation techniques. In this study, two-phase partitioning was combined with free-flow electrophoresis to produce a population of highly purified plasma membrane vesicles that were subsequently characterized by tandem mass spectroscopy. This combined high-quality plasma membrane...... isolation technique produced a reproducible proteomic library of over 1000 proteins with an extended dynamic range including plasma membrane-associated proteins. The approach enabled the detection of a number of putative plasma membrane proteins not previously identified by other studies, including...

  8. Sample clean-up, enrichment and determination of s-triazine herbicides from southern ethiopian lakes supported using liquid membrane extraction

    Directory of Open Access Journals (Sweden)

    Jan Åke Jönsson

    2000-06-01

    Full Text Available The liquid membrane extraction method has been employed for selectively extracting trace quantities of s-triazine herbicides in environmental waters collected from lakes Awassa, Chamo and Abbya, located in close proximity to the agricultural farms in Southern Ethiopia. In liquid membrane extraction, the uncharged triazine compounds from the flowing donor solution diffuse through a porous poly(tetrafluoroethylene (PTFE membrane, containing a water immiscible organic solvent. The s-triazine molecules are then irreversibly trapped in the stagnant acidic acceptor phase since they become protonated. Using both di-n-hexylether and n-undecane membrane solvents, s-traizine herbicides were extracted and low detection limits of about 1 ng/L have been obtained by extraction of three liters of sample solution spiked with 0.1 g/L of each triazine. Residues of atrazine and terbutryn ranging in concentration from 0.02 to 0.05 g/L have been successfully determined.

  9. Isotope enrichment

    International Nuclear Information System (INIS)

    Lydtin, H-J.; Wilden, R.J.; Severin, P.J.W.

    1978-01-01

    The isotope enrichment method described is based on the recognition that, owing to mass diffusion and thermal diffusion in the conversion of substances at a heated substrate while depositing an element or compound onto the substrate, enrichment of the element, or a compound of the element, with a lighter isotope will occur. The cycle is repeated for as many times as is necessary to obtain the degree of enrichment required

  10. Uranium enrichment

    International Nuclear Information System (INIS)

    1990-01-01

    This report looks at the following issues: How much Soviet uranium ore and enriched uranium are imported into the United States and what is the extent to which utilities flag swap to disguise these purchases? What are the U.S.S.R.'s enriched uranium trading practices? To what extent are utilities required to return used fuel to the Soviet Union as part of the enriched uranium sales agreement? Why have U.S. utilities ended their contracts to buy enrichment services from DOE?

  11. Imaging of iliopsoas compartment disease

    International Nuclear Information System (INIS)

    Rocher, L.; Saint Maurice, J.P.; Le Quen, O.; Bazille, A.; Miquel, A.; Frouge, C.; Blery, M.

    1997-01-01

    Infection, neoplastic involvement, and hemorrhage, are the most frequent pathologies that involve the ilio-psoas compartment. The extension from contiguous pathological structures and particularly digestive and urological organs, are often the origin of abscess formation or malignant tumours. The radiological findings including ultrasonography, CT, and magnetic resonance imaging, show a low specificity, which improves if the clinical history is known. The final diagnosis is confirmed by puncture or biopsy. (author)

  12. Numerical treatment of compartment models

    International Nuclear Information System (INIS)

    Einarsson, B.

    1984-11-01

    This report describes and interactive program RADIO (Radioactive Decay Information Online) for studying the radioactive decay process, with applications to many ecological problems, but not necessarily involving radioactive processes. Starting with the compartment coefficients and initial values of the various compartments the problem is solved as a system of linear ordinary differential equations. The method of solution is the direct use of matrix exponentials or the backward differences method. A program INVERS is also available for the solution of the inverse problem, that is parameter estimation in a system of linear ordinary differential equations when the solution is available pointwise. The output can be printed on a line printer either from a result file or from the plot file, which of course also can be used to produce graphic output. The plot file is processed by the plotting program VISION or by the auxiliary printing program RADAR. Another file can be used for a later restart from the point of time where the previous computation was aborted or from an arbitrary point of time if the relevant starting information is available. This is useful in order to avoid the manual input of a compartment matrix if it is similar to one used before. When the program RADIO is run the user answers to the question asked by the program. The programs are written in Fortran 77 for the Digital Equipment VAX 11 with graphical presentation on a Tektronix 4010, and are available from the author. (Author)

  13. Enrichment and identification of integral membrane proteins from barley aleurone layers by reversed-phase chromatography, SDS-PAGE and LC-MS/MS

    DEFF Research Database (Denmark)

    Hynek, Radovan; Svensson, Birte; Nørregaard Jensen, Ole

    2006-01-01

    was developed, comprising batch reversed-phase chromatography with stepwise elution of hydrophobic proteins by 2-propanol. Proteins in the most hydrophobic fraction were separated by SDS-PAGE and identified by LC-MS/MS and barley EST sequence database search. The method was efficient for enrichment of integral...

  14. Reticulomics: Protein-Protein Interaction Studies with Two Plasmodesmata-Localized Reticulon Family Proteins Identify Binding Partners Enriched at Plasmodesmata, Endoplasmic Reticulum, and the Plasma Membrane.

    Science.gov (United States)

    Kriechbaumer, Verena; Botchway, Stanley W; Slade, Susan E; Knox, Kirsten; Frigerio, Lorenzo; Oparka, Karl; Hawes, Chris

    2015-11-01

    The endoplasmic reticulum (ER) is a ubiquitous organelle that plays roles in secretory protein production, folding, quality control, and lipid biosynthesis. The cortical ER in plants is pleomorphic and structured as a tubular network capable of morphing into flat cisternae, mainly at three-way junctions, and back to tubules. Plant reticulon family proteins (RTNLB) tubulate the ER by dimerization and oligomerization, creating localized ER membrane tensions that result in membrane curvature. Some RTNLB ER-shaping proteins are present in the plasmodesmata (PD) proteome and may contribute to the formation of the desmotubule, the axial ER-derived structure that traverses primary PD. Here, we investigate the binding partners of two PD-resident reticulon proteins, RTNLB3 and RTNLB6, that are located in primary PD at cytokinesis in tobacco (Nicotiana tabacum). Coimmunoprecipitation of green fluorescent protein-tagged RTNLB3 and RTNLB6 followed by mass spectrometry detected a high percentage of known PD-localized proteins as well as plasma membrane proteins with putative membrane-anchoring roles. Förster resonance energy transfer by fluorescence lifetime imaging microscopy assays revealed a highly significant interaction of the detected PD proteins with the bait RTNLB proteins. Our data suggest that RTNLB proteins, in addition to a role in ER modeling, may play important roles in linking the cortical ER to the plasma membrane. © 2015 American Society of Plant Biologists. All Rights Reserved.

  15. The Fanconi anemia proteins FAA and FAC function in different cellular compartments to protect against cross-linking agent cytotoxicity.

    Science.gov (United States)

    Kruyt, F A; Youssoufian, H

    1998-10-01

    Fanconi anemia (FA) is an autosomal recessive disease characterized by chromosomal instability, bone marrow failure, and a high risk of developing malignancies. Although the disorder is genetically heterogeneous, all FA cells are defined by their sensitivity to the apoptosis-inducing effect of cross-linking agents, such as mitomycin C (MMC). The cloned FA disease genes, FAC and FAA, encode proteins with no homology to each other or to any known protein. We generated a highly specific antibody against FAA and found the protein in both the cytoplasm and nucleus of mammalian cells. By subcellular fractionation, FAA is also associated with intracellular membranes. To identify the subcellular compartment that is relevant for FAA activity, we appended nuclear export and nuclear localization signals to the carboxy terminus of FAA and enriched its localization in either the cytoplasm or the nucleus. Nuclear localization of FAA was both necessary and sufficient to correct MMC sensitivity in FA-A cells. In addition, we found no evidence for an interaction between FAA and FAC either in vivo or in vitro. Together with a previous finding that FAC is active in the cytoplasm but not in the nucleus, our results indicate that FAA and FAC function in separate subcellular compartments. Thus, FAA and FAC, if functionally linked, are more likely to be in a linear pathway rather than form a macromolecular complex to protect against cross-linker cytotoxicity.

  16. Uranium enrichment

    International Nuclear Information System (INIS)

    1989-01-01

    GAO was asked to address several questions concerning a number of proposed uranium enrichment bills introduced during the 100th Congress. The bill would have restructured the Department of Energy's uranium enrichment program as a government corporation to allow it to compete more effectively in the domestic and international markets. Some of GAO's findings discussed are: uranium market experts believe and existing market models show that the proposed DOE purchase of a $750 million of uranium from domestic producers may not significantly increase production because of large producer-held inventories; excess uranium enrichment production capacity exists throughout the world; therefore, foreign producers are expected to compete heavily in the United States throughout the 1990s as utilities' contracts with DOE expire; and according to a 1988 agreement between DOE's Offices of Nuclear Energy and Defense Programs, enrichment decommissioning costs, estimated to total $3.6 billion for planning purposes, will be shared by the commercial enrichment program and the government

  17. Forearm Compartment Syndrome Caused by Reperfusion Injury

    Directory of Open Access Journals (Sweden)

    Ufuk Sayar

    2014-01-01

    Full Text Available Compartment syndrome is commonly seen following lower extremity ischemia. However, upper extremities’ compartment syndrome, especially after any vascular surgical procedures, is infrequent. Herein we report a case of an acute forearm compartment syndrome that was developed after delayed brachial artery embolectomy.

  18. Acute compartment syndrome after medial gastrocnemius tear.

    Science.gov (United States)

    Sit, Yan Kit; Lui, Tun Hing

    2015-02-01

    Acute compartment syndrome after medial gastrocnemius tear is very rare. It can involve the superficial posterior compartment alone or progress to involve all the 4 compartments of the lower legs. Those patients with high pain tolerance and minor trauma can lead to delayed presentation. Immediate fasciotomy is the treatment of choice. Therapeutic Level IV, Case Study. © 2014 The Author(s).

  19. 14 CFR 25.787 - Stowage compartments.

    Science.gov (United States)

    2010-01-01

    ... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Personnel and Cargo Accommodations § 25.787 Stowage compartments. (a) Each compartment for the stowage of cargo, baggage, carry-on articles, and... to compartments located below, or forward, of all occupants in the airplane. If the airplane has a...

  20. Uranium enrichment

    International Nuclear Information System (INIS)

    Rae, H.K.; Melvin, J.G.

    1988-06-01

    Canada is the world's largest producer and exporter of uranium, most of which is enriched elsewhere for use as fuel in LWRs. The feasibility of a Canadian uranium-enrichment enterprise is therefore a perennial question. Recent developments in uranium-enrichment technology, and their likely impacts on separative work supply and demand, suggest an opportunity window for Canadian entry into this international market. The Canadian opportunity results from three particular impacts of the new technologies: 1) the bulk of the world's uranium-enrichment capacity is in gaseous diffusion plants which, because of their large requirements for electricity (more than 2000 kW·h per SWU), are vulnerable to competition from the new processes; 2) the decline in enrichment costs increases the economic incentive for the use of slightly-enriched uranium (SEU) fuel in CANDU reactors, thus creating a potential Canadian market; and 3) the new processes allow economic operation on a much smaller scale, which drastically reduces the investment required for market entry and is comparable with the potential Canadian SEU requirement. The opportunity is not open-ended. By the end of the century the enrichment supply industry will have adapted to the new processes and long-term customer/supplier relationships will have been established. In order to seize the opportunity, Canada must become a credible supplier during this century

  1. Development of a simplified treatment for measuring tritium concentration in the environmental water. Removal of dissolved ions by reverse osmosis membrane for electrolysis enrichment

    International Nuclear Information System (INIS)

    Koganezawa, Takayuki; Iida, Takao; Ogata, Yoshimune; Tsuji, Naruhito; Kakiuchi, Masahisa; Satake, Hiroshi; Yamanishi, Hirokuni; Sakuma, Yoichi

    2004-01-01

    An apparatus for tritium enrichment by electrolysis using solid polymer electrolyte was recently developed. The apparatus has the advantage that is to be electrolyzed without adding electrolyte to the sample water. The new treatment both being replaced the distillation process with filtration before electrolysis and being omitted the distillation process after electrolysis, was proposed. Impurities eluted by the electrolysis of ultra pure water with the device introduced no influence on tritium measurement. As alternative treatment to distillation before enrichment, micro filtration and reverse osmosis was carried out. When the sample water treated by micro filtration was electrolyzed, ions adhered both to the electrodes and the solid polymer electrolyte of the device since micro filtration cannot remove ions in the sample water. Therefore, the sample water treated by micro filtration caused some troubles in the electrolysis device. On the other hand, the sample water treated by reverse osmosis did not cause any troubles because it could remove ions. Applying the new treatment to measure some environmental waters, such as river water, resulted in an effective measurement without any influence to liquid scintillation counting. The results proved that a period of the pretreatment process of the water sample could be decreased from about 2 days to about 1.5 hours by applying the proposed treatment. A simplified treatment on the procedure of electrolysis enrichment was established for tritium measurements in the environmental water samples via liquid scintillation counting. (author)

  2. Multilayer membranes of p-sulfonato-calix[8]arene and polyvinylamine and their use for selective enrichment of rare earth metal ions

    Energy Technology Data Exchange (ETDEWEB)

    Toutianoush, Ali [Institut fuer Physikalische Chemie der Universitaet zu Koeln, Luxemburger Str. 116, D-50939 Cologne (Germany); El-Hashani, Ashraf [Institut fuer Physikalische Chemie der Universitaet zu Koeln, Luxemburger Str. 116, D-50939 Cologne (Germany); Schnepf, Judit [Institut fuer Physikalische Chemie der Universitaet zu Koeln, Luxemburger Str. 116, D-50939 Cologne (Germany); Tieke, Bernd [Institut fuer Physikalische Chemie der Universitaet zu Koeln, Luxemburger Str. 116, D-50939 Cologne (Germany)]. E-mail: Tieke@Uni-Koeln.de

    2005-06-30

    Using alternating electrostatic layer-by-layer assembly of p-octasulfonato-calix[8]arene and polyvinylamine, multilayer assemblies were built up on porous polymer supports. The resulting composite membranes with ultrathin separation layer were studied on their permeability for various metal chloride salts in aqueous solution. The membranes were permeable for sodium chloride, but much less permeable for divalent metal chlorides such as magnesium and zinc chloride, the theoretical separation factors {alpha} (NaCl/MgCl{sub 2}) and {alpha} (NaCl/ZnCl{sub 2}) being 43 and 20. Rare earth metal chlorides LnCl{sub 3} with Ln being La, Ce, Pr and Sm and the related YCl{sub 3} were strongly rejected from the membrane, the theoretical separation factors {alpha} (NaCl/LaCl{sub 3}) and {alpha} (NaCl/YCl{sub 3}) being 138 and 160, for example. Possible origins for the selective ion transport are discussed in terms of Donnan rejection of the highly charged ions and complex formation of the rare earth metal ions with the p-sulfonato-calixarene units in the membrane.

  3. Multilayer membranes of p-sulfonato-calix[8]arene and polyvinylamine and their use for selective enrichment of rare earth metal ions

    International Nuclear Information System (INIS)

    Toutianoush, Ali; El-Hashani, Ashraf; Schnepf, Judit; Tieke, Bernd

    2005-01-01

    Using alternating electrostatic layer-by-layer assembly of p-octasulfonato-calix[8]arene and polyvinylamine, multilayer assemblies were built up on porous polymer supports. The resulting composite membranes with ultrathin separation layer were studied on their permeability for various metal chloride salts in aqueous solution. The membranes were permeable for sodium chloride, but much less permeable for divalent metal chlorides such as magnesium and zinc chloride, the theoretical separation factors α (NaCl/MgCl 2 ) and α (NaCl/ZnCl 2 ) being 43 and 20. Rare earth metal chlorides LnCl 3 with Ln being La, Ce, Pr and Sm and the related YCl 3 were strongly rejected from the membrane, the theoretical separation factors α (NaCl/LaCl 3 ) and α (NaCl/YCl 3 ) being 138 and 160, for example. Possible origins for the selective ion transport are discussed in terms of Donnan rejection of the highly charged ions and complex formation of the rare earth metal ions with the p-sulfonato-calixarene units in the membrane

  4. Uranium enrichment

    International Nuclear Information System (INIS)

    Mohrhauer, H.

    1982-01-01

    The separation of uranium isotopes in order to enrich the fuel for light water reactors with the light isotope U-235 is an important part of the nuclear fuel cycle. After the basic principals of isotope separation the gaseous diffusion and the centrifuge process are explained. Both these techniques are employed on an industrial scale. In addition a short review is given on other enrichment techniques which have been demonstrated at least on a laboratory scale. After some remarks on the present situation on the enrichment market the progress in the development and the industrial exploitation of the gas centrifuge process by the trinational Urenco-Centec organisation is presented. (orig.)

  5. Liberated PKA Catalytic Subunits Associate with the Membrane via Myristoylation to Preferentially Phosphorylate Membrane Substrates.

    Science.gov (United States)

    Tillo, Shane E; Xiong, Wei-Hong; Takahashi, Maho; Miao, Sheng; Andrade, Adriana L; Fortin, Dale A; Yang, Guang; Qin, Maozhen; Smoody, Barbara F; Stork, Philip J S; Zhong, Haining

    2017-04-18

    Protein kinase A (PKA) has diverse functions in neurons. At rest, the subcellular localization of PKA is controlled by A-kinase anchoring proteins (AKAPs). However, the dynamics of PKA upon activation remain poorly understood. Here, we report that elevation of cyclic AMP (cAMP) in neuronal dendrites causes a significant percentage of the PKA catalytic subunit (PKA-C) molecules to be released from the regulatory subunit (PKA-R). Liberated PKA-C becomes associated with the membrane via N-terminal myristoylation. This membrane association does not require the interaction between PKA-R and AKAPs. It slows the mobility of PKA-C and enriches kinase activity on the membrane. Membrane-residing PKA substrates are preferentially phosphorylated compared to cytosolic substrates. Finally, the myristoylation of PKA-C is critical for normal synaptic function and plasticity. We propose that activation-dependent association of PKA-C renders the membrane a unique PKA-signaling compartment. Constrained mobility of PKA-C may synergize with AKAP anchoring to determine specific PKA function in neurons. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  6. CoMIC, the hidden dynamics of mitochondrial inner compartments.

    Science.gov (United States)

    Cho, Bongki; Sun, Woong

    2017-12-01

    Mitochondria have evolutionarily, functionally and structurally distinct outer- (OMM) and inner-membranes (IMM). Thus, mitochondrial morphology is controlled by independent but coordinated activity of fission and fusion of the OMM and IMM. Constriction and division of the OMM are mediated by endocytosis-like machineries, which include dynamin-related protein 1 with additional cytosolic vesicle scissoring machineries such as actin filament and Dynamin 2. However, structural alteration of the IMM during mitochondrial division has been poorly understood. Recently, we found that the IMM and the inner compartments undergo transient and reversible constriction prior to the OMM division, which we termed CoMIC, Constriction of Mitochondrial Inner Compartment. In this short review, we further discuss the evolutionary perspective and the regulatory mechanism of CoMIC during mitochondrial division. [BMB Reports 2017; 50(12): 597-598].

  7. Acute compartment syndrome caused by uncontrolled hypothyroidism.

    Science.gov (United States)

    Modi, Anar; Amin, Hari; Salzman, Matthew; Morgan, Farah

    2017-06-01

    Acute compartment syndrome is increased tissue pressure exceeding perfusion pressure in a closed compartment resulting in nerve and muscle ischemia. Common precipitating causes are crush injuries, burns, substance abuse, osseous or vascular limb trauma. This is a case of 42year old female with history of hypothyroidism who presented to emergency room with acute onset of severe pain and swelling in right lower extremity. Physical examination was concerning for acute compartment syndrome of right leg which was confirmed by demonstration of elevated compartmental pressures. No precipitating causes were readily identified. Further laboratory testing revealed uncontrolled hypothyroidism. Management included emergent fasciotomy and initiating thyroid hormone replacement. This case represents a rare association between acute compartment syndrome and uncontrolled hypothyroidism. We also discuss the pathogenesis of compartment syndrome in hypothyroid patients and emphasize the importance of evaluating for less common causes, particularly in setting of non-traumatic compartment syndrome. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Isotope enrichment

    International Nuclear Information System (INIS)

    Garbuny, M.

    1979-01-01

    The invention discloses a method for deriving, from a starting material including an element having a plurality of isotopes, derived material enriched in one isotope of the element. The starting material is deposited on a substrate at less than a critical submonatomic surface density, typically less than 10 16 atoms per square centimeter. The deposit is then selectively irradiated by a laser (maser or electronic oscillator) beam with monochromatic coherent radiation resonant with the one isotope causing the material including the one istope to escape from the substrate. The escaping enriched material is then collected. Where the element has two isotopes, one of which is to be collected, the deposit may be irradiated with radiation resonant with the other isotope and the residual material enriched in the one isotope may be evaporated from the substrate and collected

  9. Specific binding of (/sup 3/H)LY186126, an analogue of indolidan (LY195115), to cardiac membranes enriched in sarcoplasmic reticulum vesicles

    Energy Technology Data Exchange (ETDEWEB)

    Kauffman, R.F.; Utterback, B.G.; Robertson, D.W.

    1989-05-01

    LY186126 was found to be a potent inhibitor of type IV cyclic AMP phosphodiesterase located in the sarcoplasmic reticulum of canine cardiac muscle. This compound, a close structural analogue of indolidan (LY195115), was prepared in high specific activity, tritiated form to study the positive inotropic receptor(s) for cardiotonic phosphodiesterase inhibitors such as indolidan and milrinone. A high-affinity binding site for (/sup 3/H)LY186126 was observed (Kd = 4 nM) in purified preparations of canine cardiac sarcoplasmic reticulum vesicles. Binding was proportional to vesicle protein, was inactivated by subjecting membranes to proteolysis or boiling, and was dependent on added Mg2+. Scatchard analysis suggested the presence of a single class of binding sites in the membrane preparation. Indolidan, milrinone, and LY186126 (all at 1 microM) produced essentially complete displacement of bound (/sup 3/H)LY186126, while nifedipine, propranolol, and prazosin had little or no effect at this concentration. This represents the first reported use of a radioactive analogue to label the inotropic receptor for cardiotonic phosphodiesterase inhibitors. The results suggest that (/sup 3/H)LY186126 is a useful radioligand for examining the subcellular site(s) responsible for positive inotropic effects of these drugs.

  10. Specific binding of [3H]LY186126, an analogue of indolidan (LY195115), to cardiac membranes enriched in sarcoplasmic reticulum vesicles

    International Nuclear Information System (INIS)

    Kauffman, R.F.; Utterback, B.G.; Robertson, D.W.

    1989-01-01

    LY186126 was found to be a potent inhibitor of type IV cyclic AMP phosphodiesterase located in the sarcoplasmic reticulum of canine cardiac muscle. This compound, a close structural analogue of indolidan (LY195115), was prepared in high specific activity, tritiated form to study the positive inotropic receptor(s) for cardiotonic phosphodiesterase inhibitors such as indolidan and milrinone. A high-affinity binding site for [ 3 H]LY186126 was observed (Kd = 4 nM) in purified preparations of canine cardiac sarcoplasmic reticulum vesicles. Binding was proportional to vesicle protein, was inactivated by subjecting membranes to proteolysis or boiling, and was dependent on added Mg2+. Scatchard analysis suggested the presence of a single class of binding sites in the membrane preparation. Indolidan, milrinone, and LY186126 (all at 1 microM) produced essentially complete displacement of bound [ 3 H]LY186126, while nifedipine, propranolol, and prazosin had little or no effect at this concentration. This represents the first reported use of a radioactive analogue to label the inotropic receptor for cardiotonic phosphodiesterase inhibitors. The results suggest that [ 3 H]LY186126 is a useful radioligand for examining the subcellular site(s) responsible for positive inotropic effects of these drugs

  11. Electrokinetic migration across artificial liquid membranes. New concept for rapid sample preparation of biological fluids.

    Science.gov (United States)

    Pedersen-Bjergaard, Stig; Rasmussen, Knut Einar

    2006-03-24

    Basic drug substances were transported across a thin artificial organic liquid membrane by the application of 300 V d.c. From a 300 microl aqueous donor compartment (containing 10 mM HCl), the drugs migrated through a 200 microm artificial liquid membrane of 2-nitrophenyl octyl ether immobilized in the pores of a polypropylene hollow fiber, and into a 30 microl aqueous acceptor solution of 10 mM HCl inside the lumen of the hollow fiber. The transport was forced by an electrical potential difference sustained over the liquid membrane, resulting in electrokinetic migration of drug substances from the donor compartment to the acceptor solution. Within 5 min of operation at 300 V, pethidine, nortriptyline, methadone, haloperidol, and loperamide were extracted with recoveries in the range 70-79%, which corresponded to enrichments in the range 7.0-7.9. The chemical composition of the organic liquid membrane strongly affected the permeability, and may serve as an efficient tool for controlling the transport selectivity. Water samples, human plasma, and human urine were successfully processed, and in light of the present report, electrokinetic migration across thin artificial liquid membranes may be an interesting tool for future isolation within chemical analysis.

  12. Forearm Compartment Syndrome: Evaluation and Management.

    Science.gov (United States)

    Kistler, Justin M; Ilyas, Asif M; Thoder, Joseph J

    2018-02-01

    Compartment syndrome of the forearm is uncommon but can have devastating consequences. Compartment syndrome is a result of osseofascial swelling leading to decreased tissue perfusion and tissue necrosis. There are numerous causes of forearm compartment syndrome and high clinical suspicion must be maintained to avoid permanent disability. The most widely recognized symptoms include pain out of proportion and pain with passive stretch of the wrist and digits. Early diagnosis and decompressive fasciotomy are essential in the treatment of forearm compartment syndrome. Closure of fasciotomy wounds can often be accomplished by primary closure but many patients require additional forms of soft tissue coverage procedures. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Phosphorylation of NS5A Serine-235 is essential to hepatitis C virus RNA replication and normal replication compartment formation

    Energy Technology Data Exchange (ETDEWEB)

    Eyre, Nicholas S., E-mail: nicholas.eyre@adelaide.edu.au [School of Biological Sciences and Research Centre for Infectious Diseases, University of Adelaide, Adelaide (Australia); Centre for Cancer Biology, SA Pathology, Adelaide (Australia); Hampton-Smith, Rachel J.; Aloia, Amanda L. [School of Biological Sciences and Research Centre for Infectious Diseases, University of Adelaide, Adelaide (Australia); Centre for Cancer Biology, SA Pathology, Adelaide (Australia); Eddes, James S. [Adelaide Proteomics Centre, School of Biological Sciences, University of Adelaide, Adelaide (Australia); Simpson, Kaylene J. [Victorian Centre for Functional Genomics, Peter MacCallum Cancer Centre, East Melbourne (Australia); The Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville (Australia); Hoffmann, Peter [Adelaide Proteomics Centre, School of Biological Sciences, University of Adelaide, Adelaide (Australia); Institute for Photonics and Advanced Sensing (IPAS), University of Adelaide, Adelaide (Australia); Beard, Michael R. [School of Biological Sciences and Research Centre for Infectious Diseases, University of Adelaide, Adelaide (Australia); Centre for Cancer Biology, SA Pathology, Adelaide (Australia)

    2016-04-15

    Hepatitis C virus (HCV) NS5A protein is essential for HCV RNA replication and virus assembly. Here we report the identification of NS5A phosphorylation sites Ser-222, Ser-235 and Thr-348 during an infectious HCV replication cycle and demonstrate that Ser-235 phosphorylation is essential for HCV RNA replication. Confocal microscopy revealed that both phosphoablatant (S235A) and phosphomimetic (S235D) mutants redistribute NS5A to large juxta-nuclear foci that display altered colocalization with known replication complex components. Using electron microscopy (EM) we found that S235D alters virus-induced membrane rearrangements while EM using ‘APEX2’-tagged viruses demonstrated S235D-mediated enrichment of NS5A in irregular membranous foci. Finally, using a customized siRNA screen of candidate NS5A kinases and subsequent analysis using a phospho-specific antibody, we show that phosphatidylinositol-4 kinase III alpha (PI4KIIIα) is important for Ser-235 phosphorylation. We conclude that Ser-235 phosphorylation of NS5A is essential for HCV RNA replication and normal replication complex formation and is regulated by PI4KIIIα. - Highlights: • NS5A residues Ser-222, Ser-235 and Thr-348 are phosphorylated during HCV infection. • Phosphorylation of Ser-235 is essential to HCV RNA replication. • Mutation of Ser-235 alters replication compartment localization and morphology. • Phosphatidylinositol-4 kinase III alpha is important for Ser-235 phosphorylation.

  14. Intermolecular RNA Recombination Occurs at Different Frequencies in Alternate Forms of Brome Mosaic Virus RNA Replication Compartments

    Directory of Open Access Journals (Sweden)

    Hernan Garcia-Ruiz

    2018-03-01

    Full Text Available Positive-strand RNA viruses replicate their genomes in membrane-bound replication compartments. Brome mosaic virus (BMV replicates in vesicular invaginations of the endoplasmic reticulum membrane. BMV has served as a productive model system to study processes like virus-host interactions, RNA replication and recombination. Here we present multiple lines of evidence showing that the structure of the viral RNA replication compartments plays a fundamental role and that recruitment of parental RNAs to a common replication compartment is a limiting step in intermolecular RNA recombination. We show that a previously defined requirement for an RNA recruitment element on both parental RNAs is not to function as a preferred crossover site, but in order for individual RNAs to be recruited into the replication compartments. Moreover, modulating the form of the replication compartments from spherular vesicles (spherules to more expansive membrane layers increased intermolecular RNA recombination frequency by 200- to 1000-fold. We propose that intermolecular RNA recombination requires parental RNAs to be recruited into replication compartments as monomers, and that recruitment of multiple RNAs into a contiguous space is much more common for layers than for spherules. These results could explain differences in recombination frequencies between viruses that replicate in association with smaller spherules versus larger double-membrane vesicles and convoluted membranes.

  15. Clinical aspects of lower leg compartment syndrome

    NARCIS (Netherlands)

    Brand, Johan Gerard Henric van den

    2004-01-01

    A compartment syndrome is a condition in which increased pressure within a limited space compromises the circulation and function of tissues within that space. Although pathofysiology is roughly similar in chronic exertional and acute compartment syndrome of the lower leg, the clinical

  16. The statolith compartment in Chara rhizoids contains carbohydrate and protein

    Science.gov (United States)

    Wang-Cahill, F.; Kiss, J. Z.

    1995-01-01

    In contrast to higher plants, the alga Chara has rhizoids with single membrane-bound compartments that function as statoliths in gravity perception. Previous work has demonstrated that these statoliths contain barium sulfate crystals. In this study, we show that statoliths in Chara rhizoids react with a Coomassie Brilliant Blue cytochemical stain for proteins. While statoliths did not react with silver methenamine carbohydrate cytochemistry, the monoclonal antibody CCRC-M2, which is against a carbohydrate (sycamore-maple rhamnogalacturonan I), labeled the statolith compartment. These results demonstrate that in addition to barium sulfate, statoliths in Chara rhizoids have an organic matrix that consists of protein and carbohydrate moieties. Since the statoliths were silver methenamine negative, the carbohydrate in this compartment could be a 3-linked polysaccharide. CCRC-M2 also labeled Golgi cisternae, Golgi-associated vesicles, apical vesicles, and cell walls in the rhizoids. The specificity of CCRC-M2 immunolabeling was verified by several control experiments, including the demonstration that labeling was abolished when the antibody was preabsorbed with its antigen. Since in this and a previous study (John Z. Kiss and L. Andrew Staehelin, American Journal of Botany 80: 273-282, 1993) antibodies against higher plant carbohydrates crossreacted with cell walls of Chara in a specific manner, Characean algae may be a useful model system in biochemical and molecular studies of cell walls.

  17. Uranium enrichment

    International Nuclear Information System (INIS)

    1991-08-01

    This paper reports that in 1990 the Department of Energy began a two-year project to illustrate the technical and economic feasibility of a new uranium enrichment technology-the atomic vapor laser isotope separation (AVLIS) process. GAO believes that completing the AVLIS demonstration project will provide valuable information about the technical viability and cost of building an AVLIS plant and will keep future plant construction options open. However, Congress should be aware that DOE still needs to adequately demonstrate AVLIS with full-scale equipment and develop convincing cost projects. Program activities, such as the plant-licensing process, that must be completed before a plant is built, could take many years. Further, an updated and expanded uranium enrichment analysis will be needed before any decision is made about building an AVLIS plant. GAO, which has long supported legislation that would restructure DOE's uranium enrichment program as a government corporation, encourages DOE's goal of transferring AVLIS to the corporation. This could reduce the government's financial risk and help ensure that the decision to build an AVLIS plant is based on commercial concerns. DOE, however, has no alternative plans should the government corporation not be formed. Further, by curtailing a planned public access program, which would have given private firms an opportunity to learn about the technology during the demonstration project, DOE may limit its ability to transfer AVLIS to the private sector

  18. THE IMPACT OF THE COOKED SAUSAGE ENRICHED WITH LACTULOSE AND FOOD FIBERS ON THE MORPHOFUNCTIONAL CONDITION OF THE MUCOUS MEMBRANE OF THE LARGE INTESTINE AND MICROBIOTA (MICROBIOCENOSIS IN RATS

    Directory of Open Access Journals (Sweden)

    Leonid S. Kudryashov

    2018-01-01

    Full Text Available The researches on the development of medical and medical-preventive food products for people with violation of normal intestinal microflora are presented in the article. It was found that,  the introduction into the formulation of cooked sausage food beet  fibers based on sugar beet, hydrated in a ratio 1:5, in amount 10 %  to weight of mince and lactulose, synthesized from lactose, in  amount 640 mg/kg mince retains the traditional organoleptic  properties of the product. There were carried out comparative  morphometric, histochemical and bacterioscopic studies of boiled  sausage effect without additives and sausage enriched with food  fibers and lactulose on the morphofunctional condition of the mucous membrance of the colon (MMC of rats. Was shown a significant  height  increase of epithelial surface of epithelium, an increase of frequency mitoses in the epithelium crypts of intestinal glands (from 0.6 ± 0.08 % to 1.1 ± 0.04 %, there is a tendency of increasing  content of goblet ekzokrinnye (from 21.3 ± 5.5 % to 32.4 ± 18.7  %, while the mucosal were intensively produced allopathically  mucus, which indicates the stimulation of sausage, enriched with  lactulose on the functional status of the surface epithelium and intestinal glands of the mucous membrane of the colon. Based on the studies results of the effect of food beet fibers and lactulose,  contained in the ration of rats in large and small intestine were fixed  on order greater amount of bifido- and lactobacteries in comparison  with the animals control group. Same time, it was found that in the  large intestine the number of lactobacilli were much higher in  animals receiving experimental sausage.

  19. A Proteomics Approach to Membrane Trafficking

    NARCIS (Netherlands)

    Groen, A.J.; Vries, de S.C.; Lilley, K.S.

    2008-01-01

    Membrane trafficking, including that of integral membrane proteins as well as peripherally associated proteins, appears to be a vital process common to all eukaryotes. An important element of membrane trafficking is to determine the protein composition of the various endomembrane compartments. A

  20. The subapical compartment and its role in intracellular trafficking and cell polarity

    NARCIS (Netherlands)

    Van Ijzendoorn, Sven C. D.; Maier, Olaf; Van Der Wouden, Johanna M.; Hoekstra, Dick

    In polarized epithelial cells and hepatocytes, apical and basolateral plasma membrane surfaces are maintained, each displaying a distinct molecular composition. In recent years, it has become apparent that a subapical compartment, referred to as SAC, plays a prominent if not crucial role in the

  1. Polarized sphingolipid transport from the subapical compartment : Evidence for distinct sphingolipid domains

    NARCIS (Netherlands)

    van Ijzendoorn, SCD; Hoekstra, D

    1999-01-01

    In polarized HepG2 cells, the sphingolipids glucosylceramide and sphingomyelin (SM), transported along the reverse transcytotic pathway, are sorted in subapical compartments (SACs), and subsequently targeted to either apical or basolateral plasma membrane domains, respectively. In the present study,

  2. The longest telomeres: a general signature of adult stem cell compartments

    Science.gov (United States)

    Flores, Ignacio; Canela, Andres; Vera, Elsa; Tejera, Agueda; Cotsarelis, George; Blasco, María A.

    2008-01-01

    Identification of adult stem cells and their location (niches) is of great relevance for regenerative medicine. However, stem cell niches are still poorly defined in most adult tissues. Here, we show that the longest telomeres are a general feature of adult stem cell compartments. Using confocal telomere quantitative fluorescence in situ hybridization (telomapping), we find gradients of telomere length within tissues, with the longest telomeres mapping to the known stem cell compartments. In mouse hair follicles, we show that cells with the longest telomeres map to the known stem cell compartments, colocalize with stem cell markers, and behave as stem cells upon treatment with mitogenic stimuli. Using K15-EGFP reporter mice, which mark hair follicle stem cells, we show that GFP-positive cells have the longest telomeres. The stem cell compartments in small intestine, testis, cornea, and brain of the mouse are also enriched in cells with the longest telomeres. This constitutes the description of a novel general property of adult stem cell compartments. Finally, we make the novel finding that telomeres shorten with age in different mouse stem cell compartments, which parallels a decline in stem cell functionality, suggesting that telomere loss may contribute to stem cell dysfunction with age. PMID:18283121

  3. Abdominal compartment syndrome with acute reperfusion syndrome

    International Nuclear Information System (INIS)

    Maleeva, A.

    2017-01-01

    Abdominal compartment syndrome was recognized clinically in the 19th century when Marey and Burt observed its association with declines in respiratory function. Abdominal compartment syndrome is first used as a medical terminology from Fietsman in a case of ruptured abdominal aortic aneurysm. A condition caused by abnormally increased pressure within the abdomen. Causes of abdominal compartment syndrome include trauma, surgery, or infection. Common symptoms: abdominal distension, fast heart rate, insufficient urine production, or low blood pressure Medical procedure: nasogastric intubation Surgery: laparotomy Specialists: radiologist, primary care provider (PCP), surgeon, and emergency medicine doctor [6, 10]. Keywords: Stomach. Gastroparesis . Diabetes Mellitus [bg

  4. Abdominal Compartment Syndrome in Surgical Patients

    African Journals Online (AJOL)

    abdominal hypertension and abdominal compartment syndrome, affect ... timely surgical intervention is crucial. Key words: .... On the second postoperative day, he was noted to be restless ... Although surgery is very effective in managing ACS.

  5. Compartment syndrome in a labrador retriever

    International Nuclear Information System (INIS)

    Williams, J.; Bailey, M.Q.; Schertel, E.R.; Valentine, A.

    1994-01-01

    Compartment syndrome is an elevation of interstitial pressure in a closed osseofascial compartment that results in microvascular compromise. This report documents a clinical syndrome in the crus of a fourteen-month-old intact male Labrador Retriever which was consistent with trauma-induced compartment syndrome. A six month history of recurring trauma or complications resulted in the need for referral. Survey radiography and ultrasonography aided in the diagnosis, but the definitive answer was provided by femoral angiography. The patient was successfully treated and was discharged with normal limb function. One year later, there were no complications observed. Compartment syndrome is not uncommon in humans, and is routinely considered in certain blunt and most penetrating traumas. However, few reports of this complication in animals are found

  6. Multi-compartment microscopic diffusion imaging

    OpenAIRE

    Kaden, Enrico; Kelm, Nathaniel D.; Carson, Robert P.; Does, Mark D.; Alexander, Daniel C.

    2016-01-01

    This paper introduces a multi-compartment model for microscopic diffusion anisotropy imaging. The aim is to estimate microscopic features specific to the intra- and extra-neurite compartments in nervous tissue unconfounded by the effects of fibre crossings and orientation dispersion, which are ubiquitous in the brain. The proposed MRI method is based on the Spherical Mean Technique (SMT), which factors out the neurite orientation distribution and thus provides direct estimates of the microsco...

  7. Uranium enrichment

    International Nuclear Information System (INIS)

    1991-11-01

    This paper analyzes under four different scenarios the adequacy of a $500 million annual deposit into a fund to pay for the cost of cleaning up the Department of Energy's (DOE) three aging uranium enrichment plants. These plants are located in Oak Ridge, Tennessee; Paducah, Kentucky; and Portsmouth, Ohio. In summary the following was found: A fixed annual $500 million deposit made into a cleanup fund would not be adequate to cover total expected cleanup costs, nor would it be adequate to cover expected decontamination and decommissioning (D and D) costs. A $500 million annual deposit indexed to an inflation rate would likely be adequate to pay for all expected cleanup costs, including D and D costs, remedial action, and depleted uranium costs

  8. Plants and fungi in the era of heterogeneous plasma membranes.

    Science.gov (United States)

    Opekarová, M; Malinsky, J; Tanner, W

    2010-09-01

    Examples from yeast and plant cells are described that show that their plasma membrane is laterally compartmented. Distinct lateral domains encompassing both specific lipids and integral proteins coexist within the plane of the plasma membrane. The compartments are either spatially stable and include distinct sets of proteins, or they are transiently formed to accomplish diverse functions. They are not related to lipid rafts or their clusters, as defined for mammalian cells. This review summarises only well-documented compartments of plasma membranes from plants and fungi, which have been recognised using microscopic approaches. In several cases, physiological functions of the membrane compartmentation are revealed.

  9. Kinetic identification of an intracellular calcium compartment sensitive to phosphate and dinitrophenol in intact isolated rabbit aorta

    International Nuclear Information System (INIS)

    Hai, C.M.; Phair, R.D.

    1986-01-01

    Previous work from this laboratory revealed the presence of at least three distinct intracellular calcium compartments in intact segments of rabbit aorta. In this study one of these intracellular compartments is shown to be sensitive to dinitrophenol and to increased extracellular phosphate. Intact aortic segments were loaded with 45 Ca in bicarbonate-buffered physiologic salt solution for 1 hour, and then transferred to a flow-through chamber perfused with physiologic salt solution. Effluent from the chamber was collected for 8 hours, and 45 Ca efflux curves were analyzed using compartmental analysis. When aortic segments were loaded and washed out in dinitrophenol, the slowest component of the efflux curve was less prominent; in high phosphate it was more prominent. The rate constant changes required to account for these data were primarily in the exchange between the cytosolic and slowest intracellular calcium compartment, suggesting that the slowest calcium compartment resolved during the 8-hour washout was mitochondrial. This compartment contained 5.4 +/- 3.2 nmol calcium/g wet wt. tissue. The calcium flux across its membranes was 0.32 +/- 0.04 nmol min-1g-1. Because this flux is much smaller than the plasma-membrane calcium flux, we suggest that, in normal physiological circumstances, plasma-membrane extrusion is more important for the removal of Ca from the smooth muscle cytosol than is uptake into this slow intracellular compartment

  10. Iliopsoas compartment lesions: a radiologic evaluation

    International Nuclear Information System (INIS)

    Leao, Alberto Ribeiro de Souza; Amaral, Raquel Portugal Guimaraes; Abud, Thiago Giansante; Demarchi, Guilherme Tadeu Sauaia; Freire Filho, Edison de Oliveira; Novack, Paulo Rogerio; Campos, Flavio do Amaral; Shigueoka, David Carlos; Fernandes, Artur da Rocha Correa; Szejnfeld, Jacob; D'Ippolito, Giuseppe

    2007-01-01

    The iliopsoas compartment, a posterior boundary of the retroperitoneum, is comprised of the psoas major, psoas minor and iliac muscles. The symptoms picture in patients presenting with pathological involvement of this compartment may show a wide range of nonspecific clinical presentations that may lead to delayed diagnosis. However, in the search of an etiological diagnosis, it is already known that inflammation, tumors, and hemorrhages account for almost all the lesions affecting the iliopsoas compartment. By means of a retrospective analysis of radiological studies in patients with iliopsoas compartment lesions whose diagnosis was confirmed by anatomopathological evaluation or clinical follow-up, we have reviewed its anatomy as well as the main forms of involvement, with the purpose of identifying radiological signs that may help to narrow down the potential differential diagnoses. As each lesion is approached we will discuss the main radiological findings such as presence of gas in pyogenic abscesses, bone destruction and other bone changes of vertebral bodies in lesions secondary to tuberculosis, involvement of fascial planes in cases of neoplasms, and differences in signal density and intensity of hematomas secondary to hemoglobin degradation, among others. So, we have tried to present cases depicting the most frequent lesions involving the iliopsoas compartment, with emphasis on those signs that can lead us to a more specific etiological diagnosis. (author)

  11. Iliopsoas compartment lesions: a radiologic evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Leao, Alberto Ribeiro de Souza; Amaral, Raquel Portugal Guimaraes; Abud, Thiago Giansante; Demarchi, Guilherme Tadeu Sauaia; Freire Filho, Edison de Oliveira; Novack, Paulo Rogerio; Campos, Flavio do Amaral; Shigueoka, David Carlos; Fernandes, Artur da Rocha Correa; Szejnfeld, Jacob; D' Ippolito, Giuseppe [Universidade Federal de Sao Paulo (UNIFESP-EPM), Sao Paulo, SP (Brazil). Dept. de Diagnostico por Imagem]. E-mail: ar.leao@uol.com.br; Santos, Jose Eduardo Mourao [Universidade Federal de Sao Paulo (UNIFESP-EPM), Sao Paulo, SP (Brazil)

    2007-07-15

    The iliopsoas compartment, a posterior boundary of the retroperitoneum, is comprised of the psoas major, psoas minor and iliac muscles. The symptoms picture in patients presenting with pathological involvement of this compartment may show a wide range of nonspecific clinical presentations that may lead to delayed diagnosis. However, in the search of an etiological diagnosis, it is already known that inflammation, tumors, and hemorrhages account for almost all the lesions affecting the iliopsoas compartment. By means of a retrospective analysis of radiological studies in patients with iliopsoas compartment lesions whose diagnosis was confirmed by anatomopathological evaluation or clinical follow-up, we have reviewed its anatomy as well as the main forms of involvement, with the purpose of identifying radiological signs that may help to narrow down the potential differential diagnoses. As each lesion is approached we will discuss the main radiological findings such as presence of gas in pyogenic abscesses, bone destruction and other bone changes of vertebral bodies in lesions secondary to tuberculosis, involvement of fascial planes in cases of neoplasms, and differences in signal density and intensity of hematomas secondary to hemoglobin degradation, among others. So, we have tried to present cases depicting the most frequent lesions involving the iliopsoas compartment, with emphasis on those signs that can lead us to a more specific etiological diagnosis. (author)

  12. Shigella subverts the host recycling compartment to rupture its vacuole.

    Science.gov (United States)

    Mellouk, Nora; Weiner, Allon; Aulner, Nathalie; Schmitt, Christine; Elbaum, Michael; Shorte, Spencer L; Danckaert, Anne; Enninga, Jost

    2014-10-08

    Shigella enters epithlial cells via internalization into a vacuole. Subsequent vacuolar membrane rupture allows bacterial escape into the cytosol for replication and cell-to-cell spread. Bacterial effectors such as IpgD, a PI(4,5)P2 phosphatase that generates PI(5)P and alters host actin, facilitate this internalization. Here, we identify host proteins involved in Shigella uptake and vacuolar membrane rupture by high-content siRNA screening and subsequently focus on Rab11, a constituent of the recycling compartment. Rab11-positive vesicles are recruited to the invasion site before vacuolar rupture, and Rab11 knockdown dramatically decreases vacuolar membrane rupture. Additionally, Rab11 recruitment is absent and vacuolar rupture is delayed in the ipgD mutant that does not dephosphorylate PI(4,5)P₂ into PI(5)P. Ultrastructural analyses of Rab11-positive vesicles further reveal that ipgD mutant-containing vacuoles become confined in actin structures that likely contribute to delayed vacular rupture. These findings provide insight into the underlying molecular mechanism of vacuole progression and rupture during Shigella invasion. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Post-dialysis urea concentration: comparison between one- compartment model and two-compartment model

    International Nuclear Information System (INIS)

    Tamrin, N S Ahmad; Ibrahim, N

    2014-01-01

    The reduction of the urea concentration in blood can be numerically projected by using one-compartment model and two-compartment model with no variation in body fluid. This study aims to compare the simulated values of post-dialysis urea concentration for both models with the clinical data obtained from the hospital. The clinical assessment of adequacy of a treatment is based on the value of Kt/V. Further, direct calculation using clinical data and one-compartment model are presented in the form of ratio. It is found that the ratios of postdialysis urea concentration simulated using two-compartment model are higher compared to the ratios of post-dialysis urea concentration using one-compartment model. In addition, most values of post-dialysis urea concentration simulated using two-compartment model are much closer to the clinical data compared to values simulated using one-compartment model. Kt/V values calculated directly using clinical data are found to be higher than Kt/V values derived from one-compartment model

  14. Involvement of the mitochondrial compartment in human NCL fibroblasts

    International Nuclear Information System (INIS)

    Pezzini, Francesco; Gismondi, Floriana; Tessa, Alessandra; Tonin, Paola; Carrozzo, Rosalba; Mole, Sara E.; Santorelli, Filippo M.; Simonati, Alessandro

    2011-01-01

    Highlights: ► Mitochondrial reticulum fragmentation occurs in human CLN1 and CLN6 fibroblasts. ► Likewise mitochondrial shift-to periphery and decreased mitochondrial density are seen. ► Enhanced caspase-mediated apoptosis occurs following STS treatment in CLN1 fibroblasts. -- Abstract: Neuronal ceroid lipofuscinosis (NCL) are a group of progressive neurodegenerative disorders of childhood, characterized by the endo-lysosomal storage of autofluorescent material. Impaired mitochondrial function is often associated with neurodegeneration, possibly related to the apoptotic cascade. In this study we investigated the possible effects of lysosomal accumulation on the mitochondrial compartment in the fibroblasts of two NCL forms, CLN1 and CLN6. Fragmented mitochondrial reticulum was observed in all cells by using the intravital fluorescent marker Mitotracker, mainly in the perinuclear region. This was also associated with intense signal from the lysosomal markers Lysotracker and LAMP2. Likewise, mitochondria appeared to be reduced in number and shifted to the cell periphery by electron microscopy; moreover the mitochondrial markers VDCA and COX IV were reduced following quantitative Western blot analysis. Whilst there was no evidence of increased cell death under basal condition, we observed a significant increase in apoptotic nuclei following Staurosporine treatment in CLN1 cells only. In conclusion, the mitochondrial compartment is affected in NCL fibroblasts invitro, and CLN1 cells seem to be more vulnerable to the negative effects of stressed mitochondrial membrane than CLN6 cells.

  15. Polarized trafficking: the palmitoylation cycle distributes cytoplasmic proteins to distinct neuronal compartments.

    Science.gov (United States)

    Tortosa, Elena; Hoogenraad, Casper C

    2018-02-01

    In neurons, polarized cargo distribution occurs mainly between the soma and axonal and dendritic compartments, and requires coordinated regulation of cytoskeletal remodeling and membrane trafficking. The Golgi complex plays a critical role during neuronal polarization and secretory trafficking has been shown to differentially transport proteins to both axons and dendrites. Besides the Golgi protein sorting, recent data revealed that palmitoylation cycles are an efficient mechanism to localize cytoplasmic, non-transmembrane proteins to particular neuronal compartments, such as the newly formed axon. Palmitoylation allows substrate proteins to bind to and ride with Golgi-derived secretory vesicles to all neuronal compartments. By allowing cytoplasmic proteins to 'hitchhike' on transport carriers in a non-polarized fashion, compartmentalized depalmitoylation may act as a selective retention mechanism. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. [The perichromatin compartment of the cell nucleus].

    Science.gov (United States)

    Bogoliubov, D S

    2014-01-01

    In this review, the data on the structure and composition of the perichromatin compartment, a special border area between the condensed chromatin and the interchromatin space of the cell nucleus, are discussed in the light of the concept of nuclear functions in complex nuclear architectonics. Morphological features, molecular composition and functions of main extrachromosomal structures of the perichromatin compartment, perichromatin fibrils (PFs) and perichromatin granules (PGs) including nuclear stress-bodies (nSBs) that are derivates of the PGs under heat shock, are presented. A special attention was paid to the features of the molecular compositions of PFs and PGs in different cell types and at different physiological conditions.

  17. Effects of combustible stacking in large compartments

    DEFF Research Database (Denmark)

    Gentili, Filippo; Giuliani, Luisa; Bontempi, Franco

    2013-01-01

    This paper focuses on the modelling of fire in case of various distributions of combustible materials in a large compartment. Large compartments often represent a challenge for structural fire safety, because of lack of prescriptive rules to follow and difficulties of taking into account the effect...... of non uniform distribution of the combustible materials and fire propagation. These aspects are discussed in this paper with reference to an industrial steel building, taken as case study. Fires triggered by the burning of wooden pallets stored in the premises have been investigated with respect...

  18. The method of water enrichment in oxygen-18

    International Nuclear Information System (INIS)

    Chmielewski, A.G.; Zakrzewska-Trznadel, G.; Van Hook, A.; Milievic, N.R.

    1996-01-01

    The process of membrane distillation has been used for water enrichment in oxygen-18. The hydrophobic PTFE membranes has been used as a boundary for liquids being at different temperatures on the each side of membrane. Example of obtained results have been shown

  19. Feasibility of using sodium chloride as a tracer for the characterization of the distribution of matter in complex multi-compartment 3D bioreactors for stem cell culture.

    Science.gov (United States)

    Gerlach, Jörg C; Witaschek, Tom; Strobel, Catrin; Brayfield, Candace A; Bornemann, Reinhard; Catapano, Gerardo; Zeilinger, Katrin

    2010-06-01

    The experimental characterization of the distribution of matter in complex multi-compartment three-dimensional membrane bioreactors for human cell culture is complicated by tracer interactions with the membranes and other bioreactor constituents. This is due to the fact that membranes with a high specific surface area often feature a hydrophobic chemical backbone that may adsorb tracers often used to this purpose, such as proteins and dyes. Membrane selectivity, and its worsening caused by protein adsorption, may also hinder tracer transfer across neighboring compartments, thus preventing effective characterization of the distribution of matter in the whole bioreactor. Tracer experiments with sodium chloride (NaCl) may overcome some of these limitations and be effectively used to characterize the distribution of matter in complex 3D multi-compartments membrane bioreactors for stem cell culture. NaCl freely permeates most used membranes, it does not adsorb on uncharged membranes, and its concentration may be accurately measured in terms of solution conductivity. In this preliminary study, the feasibility of complex multi-compartment membrane bioreactors was investigated with a NaCl concentration pulse challenge to characterize how their distribution of matter changes when they are operated under different conditions. In particular, bioreactors consisting of three different membrane types stacked on top of one another to form a 3D network were characterized under different feed conditions.

  20. Membrane Compartmentalization Reducing the Mobility of Lipids and Proteins within a Model Plasma Membrane.

    Science.gov (United States)

    Koldsø, Heidi; Reddy, Tyler; Fowler, Philip W; Duncan, Anna L; Sansom, Mark S P

    2016-09-01

    The cytoskeleton underlying cell membranes may influence the dynamic organization of proteins and lipids within the bilayer by immobilizing certain transmembrane (TM) proteins and forming corrals within the membrane. Here, we present coarse-grained resolution simulations of a biologically realistic membrane model of asymmetrically organized lipids and TM proteins. We determine the effects of a model of cytoskeletal immobilization of selected membrane proteins using long time scale coarse-grained molecular dynamics simulations. By introducing compartments with varying degrees of restraints within the membrane models, we are able to reveal how compartmentalization caused by cytoskeletal immobilization leads to reduced and anomalous diffusional mobility of both proteins and lipids. This in turn results in a reduced rate of protein dimerization within the membrane and of hopping of membrane proteins between compartments. These simulations provide a molecular realization of hierarchical models often invoked to explain single-molecule imaging studies of membrane proteins.

  1. Juvenile psittacine environmental enrichment.

    Science.gov (United States)

    Simone-Freilicher, Elisabeth; Rupley, Agnes E

    2015-05-01

    Environmental enrichment is of great import to the emotional, intellectual, and physical development of the juvenile psittacine and their success in the human home environment. Five major types of enrichment include social, occupational, physical, sensory, and nutritional. Occupational enrichment includes exercise and psychological enrichment. Physical enrichment includes the cage and accessories and the external home environment. Sensory enrichment may be visual, auditory, tactile, olfactory, or taste oriented. Nutritional enrichment includes variations in appearance, type, and frequency of diet, and treats, novelty, and foraging. Two phases of the preadult period deserve special enrichment considerations: the development of autonomy and puberty. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Leg 201Tl-SPECT in chronic exertional compartment syndrome

    International Nuclear Information System (INIS)

    Elkadri, N.; Slim, I.; Blondet, C.; Choquet, Ph.; Constantinesco, A.; Lecocq, J.

    2004-01-01

    Leg 201 Tl-SPECT in chronic exertional compartment syndrome Background: The chronic exertional compartment syndrome is one of the most frequent origins regarding leg pain due to sport training. The diagnosis can be established by invasive compartment pressure measurement. The aim of this study is to evaluate the role that could have 201 Tl-SPECT for patients with suspicion of compartment syndrome. Patients and methods: 51 leg 201 Tl-SPECT exams were performed (exercise - and rest without reinjection) in 49 patients; 28 had compartment syndrome confirmed by pressure measurement. About 100 MBq of 201 Tl were injected during exercise, when pain appeared or at least after 25 minutes exercise. We studied mean percentages of level uptake for each compartment, referred to the maximal uptake of both legs. Results: 47 compartments were concerned by compartment syndrome and 361 compartments were not. Scintigraphic patterns in compartments are reversible ischaemia (45%), uptake stability (36%) or reverse redistribution (19%); these patterns are not linked to compartment syndrome. However, there is a significant difference of rest 201 Tl level uptake between compartments with and without compartment syndrome and a significant correlation between muscular pressure measurement and rest level uptake. Conclusion: 201 Tl-SPECT shows that only ischaemia does not explain compartment syndrome. Moreover, it allows to predict pressure variation during exercise but it does not offer any interest in order to select patients for muscular invasive pressure measurement. (author)

  3. Herpes simplex virus replication compartments can form by coalescence of smaller compartments

    International Nuclear Information System (INIS)

    Taylor, Travis J; McNamee, Elizabeth E.; Day, Cheryl; Knipe, David M.

    2003-01-01

    Herpes simplex virus (HSV) uses intranuclear compartmentalization to concentrate the viral and cellular factors required for the progression of the viral life cycle. Processes as varied as viral DNA replication, late gene expression, and capsid assembly take place within discrete structures within the nucleus called replication compartments. Replication compartments are hypothesized to mature from a few distinct structures, called prereplicative sites, that form adjacent to cellular nuclear matrix-associated ND10 sites. During productive infection, the HSV single-stranded DNA-binding protein ICP8 localizes to replication compartments. To further the understanding of replication compartment maturation, we have constructed and characterized a recombinant HSV-1 strain that expresses an ICP8 molecule with green fluorescent protein (GFP) fused to its C terminus. In transfected Vero cells that were infected with HSV, the ICP8-GFP protein localized to prereplicative sites in the presence of the viral DNA synthesis inhibitor phosphonoacetic acid (PAA) or to replication compartments in the absence of PAA. A recombinant HSV-1 strain expressing the ICP8-GFP virus replicated in Vero cells, but the yield was increased by 150-fold in an ICP8-complementing cell line. Using the ICP8-GFP protein as a marker for replication compartments, we show here that these structures start as punctate structures early in infection and grow into large, globular structures that eventually fill the nucleus. Large replication compartments were formed by small structures that either moved through the nucleus to merge with adjacent compartments or remained relatively stationary within the nucleus and grew by accretion and fused with neighboring structures

  4. Gas separation with membranes

    International Nuclear Information System (INIS)

    Schulz, G.; Michele, H.; Werner, U.

    1982-01-01

    Gas separation with membranes has already been tested in numerous fields of application, e.g. uranium enrichment of H 2 separation. In many of these processes the mass transfer units, so-called permeators, have to be connected in tandem in order to achieve high concentrations. A most economical operating method provides for each case an optimization of the cascades with regard to the membrane materials, construction and design of module. By utilization of the concentration gradient along the membrane a new process development has been accomplished - the continuously operating membrane rectification unit. Investment and operating costs can be reduced considerably for a number of separating processes by combining a membrane rectification unit with a conventional recycling cascade. However, the new procedure requires that the specifications for the module construction, flow design, and membrane properties be reconsidered. (orig.) [de

  5. Separating attoliter-sized compartments using fluid pore-spanning lipid bilayers.

    Science.gov (United States)

    Lazzara, Thomas D; Carnarius, Christian; Kocun, Marta; Janshoff, Andreas; Steinem, Claudia

    2011-09-27

    Anodic aluminum oxide (AAO) is a porous material having aligned cylindrical compartments with 55-60 nm diameter pores, and being several micrometers deep. A protocol was developed to generate pore-spanning fluid lipid bilayers separating the attoliter-sized compartments of the nanoporous material from the bulk solution, while preserving the optical transparency of the AAO. The AAO was selectively functionalized by silane chemistry to spread giant unilamellar vesicles (GUVs) resulting in large continuous membrane patches covering the pores. Formation of fluid single lipid bilayers through GUV rupture could be readily observed by fluorescence microscopy and further supported by conservation of membrane surface area, before and after GUV rupture. Fluorescence recovery after photobleaching gave low immobile fractions (5-15%) and lipid diffusion coefficients similar to those found for bilayers on silica. The entrapment of molecules within the porous underlying cylindrical compartments, as well as the exclusion of macromolecules from the nanopores, demonstrate the barrier function of the pore-spanning membranes and could be investigated in three-dimensions using confocal laser scanning fluorescence imaging. © 2011 American Chemical Society

  6. Arbuscules of vesicular-arbuscular mycorrhizal fungi inhabit an acidic compartment within plant roots.

    Science.gov (United States)

    Guttenberger, M

    2000-08-01

    The most widespread type of mycorrhiza is the so-called vesicular-arbuscular mycorrhiza. In this endomycorrhiza, fungal hyphae penetrate plant cell walls in the root cortex. There they form densely branched arbuscules. Fungus and plant plasma membrane are separated by a common interfacial apoplast. The pH of the compartment between the symbionts is of pivotal importance for nutrient transfer. Histochemical experiments were conducted to check for an acidic nature of the interface in the model system Glomus versiforme (Karst.) Berch-Allium porrum L. Two chemically different acidotropic dyes (neutral red and LysoSensor Green DND-189) stained the arbuscules intensely. The staining of arbuscules could be eliminated by addition of the protonophore carbonylcyanide m-chlorophenylhydrazone (CCCP) or treatments leading to membrane rupture. Therefore, the staining of the arbuscules was based on the ion-trap mechanism, which indicates acidic, membrane-bound compartments. Microscopic examination of stained arbuscules at high optical resolution revealed a peripheral accumulation of the dye. Since plasmolysis rapidly destained the arbuscules, it is concluded that the dyes accumulate in the arbuscular interface, indicating the highly acidic nature of this compartment. The findings are discussed with respect to their relevance for the nutrient transfer in mycorrhizas. In addition, evidence for a discontinuity in the arbuscular interface between the stem and the branches of the arbuscule is given.

  7. Prelysosomal Compartments in the Unconventional Secretion of Amyloidogenic Seeds

    Directory of Open Access Journals (Sweden)

    Helena Borland

    2017-01-01

    Full Text Available A mechanistic link between neuron-to-neuron transmission of secreted amyloid and propagation of protein malconformation cytopathology and disease has recently been uncovered in animal models. An enormous interest in the unconventional secretion of amyloids from neurons has followed. Amphisomes and late endosomes are the penultimate maturation products of the autophagosomal and endosomal pathways, respectively, and normally fuse with lysosomes for degradation. However, under conditions of perturbed membrane trafficking and/or lysosomal deficiency, prelysosomal compartments may instead fuse with the plasma membrane to release any contained amyloid. After a brief introduction to the endosomal and autophagosomal pathways, we discuss the evidence for autophagosomal secretion (exophagy of amyloids, with a comparative emphasis on Aβ1–42 and α-synuclein, as luminal and cytosolic amyloids, respectively. The ESCRT-mediated import of cytosolic amyloid into late endosomal exosomes, a known vehicle of transmission of macromolecules between cells, is also reviewed. Finally, mechanisms of lysosomal dysfunction, deficiency, and exocytosis are exemplified in the context of genetically identified risk factors, mainly for Parkinson’s disease. Exocytosis of prelysosomal or lysosomal organelles is a last resort for clearance of cytotoxic material and alleviates cytopathy. However, they also represent a vehicle for the concentration, posttranslational modification, and secretion of amyloid seeds.

  8. Other enrichment related contracts

    International Nuclear Information System (INIS)

    Hall, J.C.

    1978-01-01

    In addition to long-term enrichment contracts, DOE has other types of contracts: (1) short-term, fixed-commitment enrichment contract; (2) emergency sales agreement for enriched uranium; (3) feed material lease agreement; (4) enriched uranium storage agreement; and (5) feed material usage agreement

  9. Selective separation and concentration of antihypertensive peptides from rapeseed protein hydrolysate by electrodialysis with ultrafiltration membranes.

    Science.gov (United States)

    He, Rong; Girgih, Abraham T; Rozoy, Elodie; Bazinet, Laurent; Ju, Xing-Rong; Aluko, Rotimi E

    2016-04-15

    Rapeseed protein isolate was subjected to alcalase digestion to obtain a protein hydrolysate that was separated into peptide fractions using electrodialysis with ultrafiltration membrane (EDUF) technology. The EDUF process (6h duration) led to isolation of three peptide fractions: anionic (recovered in KCl-1 compartment), cationic (recovered in KCl-2 compartment), and those that remained in the feed compartment, which was labeled final rapeseed protein hydrolysate (FRPH). As expected the KCl-1 peptides were enriched in negatively-charged (43.57%) while KCl-2 contained high contents of positively-charged (28.35%) amino acids. All the samples inhibited angiotensin converting enzyme (ACE) and renin activities in dose-dependent manner with original rapeseed protein hydrolysate having the least ACE-inhibitory IC50 value of 0.0932±0.0037 mg/mL while FRPH and KCl-2 had least renin-inhibitory IC50 values of 0.47±0.05 and 0.55±0.06 mg/mL, respectively. Six hours after oral administration (100 mg/kg body weight) to spontaneously hypertensive rats, the FRPH produced the maximum systolic blood pressure reduction of -51 mmHg. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Multi-compartment Aerosol Transport Model

    Energy Technology Data Exchange (ETDEWEB)

    Hubbard, Joshua Allen; Santarpia, Joshua; Brotherton, Christopher M.; Omana, Michael Alexis; Rivera, Danielle; Lucero, Gabriel Anthony

    2017-06-01

    A simple aerosol transport model was developed for a multi-compartmented cleanroom. Each compartment was treated as a well-mixed volume with ventilating supply and return air. Gravitational settling, intercompartment transport, and leakage of exterior air into the system were included in the model. A set of first order, coupled, ordinary differential equations was derived from the conservation equations of aerosol mass and air mass. The system of ODEs was then solved in MATLAB using pre-existing numerical methods. The model was verified against cases of (1) constant inlet-duct concentration, and (2) exponentially decaying inlet-duct concentration. Numerical methods resulted in normalized error of less than 10 -9 when model solutions were compared to analytical solutions. The model was validated against experimental measurements from a single field test and showed good agreement in the shape and magnitude of the aerosol concentration profile with time.

  11. A modern definition of mediastinal compartments.

    Science.gov (United States)

    Carter, Brett W; Tomiyama, Noriyuki; Bhora, Faiz Y; Rosado de Christenson, Melissa L; Nakajima, Jun; Boiselle, Phillip M; Detterbeck, Frank C; Marom, Edith M

    2014-09-01

    Division of the mediastinum into compartments is used to help narrow the differential diagnosis of newly detected mediastinal masses, to assist in planning biopsy and surgical procedures, and to facilitate communication among clinicians of multiple disciplines. Several traditional mediastinal division schemes exist based upon arbitrary landmarks on the lateral chest radiograph. We describe a modern, computed tomography-based mediastinal division scheme, which has been accepted by the International Thymic Malignancy Interest Group as a new standard. This clinical classification defines a prevascular (anterior), a visceral (middle), and a paravertebral (posterior) compartment, with anatomic boundaries defined clearly by computed tomography. It is our intention that this definition be used in the reporting of clinical cases and the design of prospective clinical trials.

  12. Hermetic compartments leak-tightness enhancement

    International Nuclear Information System (INIS)

    Murani, J.

    2000-01-01

    In connection with the enhancement of the nuclear safety of the Jaslovske Bohunice V-1 NPP actions for the increase of the leak tightness are performed. The reconstruction has been done in the following directions: hermetic compartments leak tightness enhancement; air lock installation; installation of air lock in SP 4 vent system; integrated leakage rate test to hermetic compartments with leak detection. After 'major' leaks on the hermetic boundary components had been eliminated, since 1994 works on a higher qualitative level began. The essence of the works consists in the detection and identification of leaks in the structural component of the hermetic boundary during the planned refueling outages. The results of the Small Reconstruction and gradual enhancement of leak tightness are presented

  13. Function of plasma membrane microdomain-associated proteins during legume nodulation.

    Science.gov (United States)

    Qiao, Zhenzhen; Libault, Marc

    2017-10-03

    Plasma membrane microdomains are plasma membrane sub-compartments enriched in sphingolipids and sterols, and composed by a specific set of proteins. They are involved in recognizing signal molecules, transducing these signals, and controlling endocytosis and exocytosis processes. In a recent study, applying biochemical and microscopic methods, we characterized the soybean GmFWL1 protein, a major regulator of soybean nodulation, as a new membrane microdomain-associated protein. Interestingly, upon rhizobia inoculation of the soybean root system, GmFWL1 and one of its interacting partners, GmFLOT2/4, both translocate to the root hair cell tip, the primary site of interaction and infection between soybean and Rhizobium. The role of GmFWL1 as a plasma membrane microdomain-associated protein is also supported by immunoprecipitation assays performed on soybean nodules, which revealed 178 GmFWL1 protein partners including a large number of microdomain-associated proteins such as GmFLOT2/4. In this addendum, we provide additional information about the identity of the soybean proteins repetitively identified as GmFWL1 protein partners. Their function is discussed especially in regard to plant-microbe interactions and microbial symbiosis. This addendum will provide new insights in the role of plasma membrane microdomains in regulating legume nodulation.

  14. Monoterpene biosynthesis potential of plant subcellular compartments.

    Science.gov (United States)

    Dong, Lemeng; Jongedijk, Esmer; Bouwmeester, Harro; Van Der Krol, Alexander

    2016-01-01

    Subcellular monoterpene biosynthesis capacity based on local geranyl diphosphate (GDP) availability or locally boosted GDP production was determined for plastids, cytosol and mitochondria. A geraniol synthase (GES) was targeted to plastids, cytosol, or mitochondria. Transient expression in Nicotiana benthamiana indicated local GDP availability for each compartment but resulted in different product levels. A GDP synthase from Picea abies (PaGDPS1) was shown to boost GDP production. PaGDPS1 was also targeted to plastids, cytosol or mitochondria and PaGDPS1 and GES were coexpressed in all possible combinations. Geraniol and geraniol-derived products were analyzed by GC-MS and LC-MS, respectively. GES product levels were highest for plastid-targeted GES, followed by mitochondrial- and then cytosolic-targeted GES. For each compartment local boosting of GDP biosynthesis increased GES product levels. GDP exchange between compartments is not equal: while no GDP is exchanged from the cytosol to the plastids, 100% of GDP in mitochondria can be exchanged to plastids, while only 7% of GDP from plastids is available for mitochondria. This suggests a direct exchange mechanism for GDP between plastids and mitochondria. Cytosolic PaGDPS1 competes with plastidial GES activity, suggesting an effective drain of isopentenyl diphosphate from the plastids to the cytosol. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  15. Perfluoroalkyl acid distribution in various plant compartments ...

    Science.gov (United States)

    Crop uptake of perfluoroalkyl acids (PFAAs) from biosolids-amended soil has been identified as a potential pathway for PFAA entry into the terrestrial food chain. This study compared the uptake of PFAAs in greenhouse-grown radish (Raphanus sativus), celery (Apium graveolens var.dulce), tomato (Lycopersicon lycopersicum), and sugar snap pea (Pisum sativum var. macrocarpon) from an industrially impacted biosolids-amended soil, a municipal biosolids­ amended soil, and a control soil. Individual concentrations of PFAAs, on a dry weight basis, in mature, edible portions of crops grown in soil amended with PFAA industrially impacted biosolids were highest for perfluorooctanoate (PFOA; 67 ng/g) in radish root, perfluorobutanoate (PFBA;232 ng/g) in celery shoot, and PFBA (150 ng/g) in pea fruit. Comparatively, PFAA concentrations in edible compartments of crops grown in the municipal biosolids-amended soil and in the control soil were less than 25 ng/g. Bioaccumulation factors (BAFs) were calculated for the root, shoot, and fruit compartments (as applicable) of all crops grown in the industrially impacted soil. BAFs were highest for PFBA in the shoots of all crops, as well as in the fruit compartment of pea. Root­ soil concentration factors (RCFs) for tomato and pea were independent of PFAA chain length, while radish and celery RCFs showed a slight decrease with increasing chain length. Shoot-soil concentration factors (SCFs) for all crops showed a decrease with incre

  16. Salus: Kernel Support for Secure Process Compartments

    Directory of Open Access Journals (Sweden)

    Raoul Strackx

    2015-01-01

    Full Text Available Consumer devices are increasingly being used to perform security and privacy critical tasks. The software used to perform these tasks is often vulnerable to attacks, due to bugs in the application itself or in included software libraries. Recent work proposes the isolation of security-sensitive parts of applications into protected modules, each of which can be accessed only through a predefined public interface. But most parts of an application can be considered security-sensitive at some level, and an attacker who is able to gain inapplication level access may be able to abuse services from protected modules. We propose Salus, a Linux kernel modification that provides a novel approach for partitioning processes into isolated compartments sharing the same address space. Salus significantly reduces the impact of insecure interfaces and vulnerable compartments by enabling compartments (1 to restrict the system calls they are allowed to perform, (2 to authenticate their callers and callees and (3 to enforce that they can only be accessed via unforgeable references. We describe the design of Salus, report on a prototype implementation and evaluate it in terms of security and performance. We show that Salus provides a significant security improvement with a low performance overhead, without relying on any non-standard hardware support.

  17. Evaluation of acute compartment syndrome of extremities in ...

    African Journals Online (AJOL)

    Arun Kumar Agnihotri

    compartment syndrome in children; Acute compartment syndrome and fasciotomy. INTRODUCTIONᴪ .... these patients were manipulated under general anaesthesia ... of these children. The clinical diagnosis of increased ICP is not easy.

  18. Compartment syndrome can also be seen in the forearm

    DEFF Research Database (Denmark)

    Asmar, Ali; Broholm, Rikke; Bülow, Jens

    2014-01-01

    Chronic compartment syndrome is a challenge for the clinician and symptomatic similar to neuropathies, tenosynovitis, stress fractures and referred pain from lumbar cervicalis. Thus, chronic compartment syndrome of the upper extremities is probably an underdiagnosed condition. In patients...

  19. 14 CFR 23.853 - Passenger and crew compartment interiors.

    Science.gov (United States)

    2010-01-01

    ... Photographic Film PH1.25 (available from the American National Standards Institute, 1430 Broadway, New York, N... stowage compartments and compartments for stowing small items such as magazines and maps) must be self...

  20. Analysis of outer membrane vesicle associated proteins isolated from the plant pathogenic bacterium Xanthomonas campestris pv. campestris

    Directory of Open Access Journals (Sweden)

    Niehaus Karsten

    2008-06-01

    Full Text Available Abstract Background Outer membrane vesicles (OMVs are released from the outer membrane of many Gram-negative bacteria. These extracellular compartments are known to transport compounds involved in cell-cell signalling as well as virulence associated proteins, e.g. the cytolysine from enterotoxic E. coli. Results We have demonstrated that Xanthomonas campestris pv. campestris (Xcc releases OMVs into the culture supernatant during growth. A proteome study identified 31 different proteins that associate with the OMV fraction of which half are virulence-associated. A comparison with the most abundant outer membrane (OM proteins revealed that some proteins are enriched in the OMV fraction. This may be connected to differences in the LPS composition between the OMVs and the OM. Furthermore, a comparison of the OMV proteomes from two different culture media indicated that the culture conditions have an impact on the protein composition. Interestingly, the proteins that are common to both culture conditions are mainly involved in virulence. Conclusion Outer membrane vesicles released from the OM of Xcc contain membrane- and virulence-associated proteins. Future experiments will prove whether these structures can serve as "vehicles" for the transport of virulence factors into the host membrane.

  1. Furrow-like invaginations of the yeast plasma membrane correspond to membrane compartment of Can1

    Czech Academy of Sciences Publication Activity Database

    Strádalová, Vendula; Stahlschmidt, W.; Grossmann, Q.; Blažíková, Michaela; Rachel, R.; Tanner, W.; Malínský, Jan

    2009-01-01

    Roč. 122, č. 16 (2009), s. 2887-2894 ISSN 0021-9533 R&D Projects: GA ČR GA204/07/0133; GA ČR GC204/08/J024 Grant - others:GA AV ČR(CZ) KAN200520801 Program:IA Institutional research plan: CEZ:AV0Z50390703 Keywords : eisosome * electron microscopy * MCC Subject RIV: EA - Cell Biology Impact factor: 6.144, year: 2009

  2. Optimizing aeration rates for minimizing membrane fouling and its effect on sludge characteristics in a moving bed membrane bioreactor

    International Nuclear Information System (INIS)

    Rahimi, Yousef; Torabian, Ali; Mehrdadi, Naser; Habibi-Rezaie, Mehran; Pezeshk, Hamid; Nabi-Bidhendi, Gholam-Reza

    2011-01-01

    Research highlights: → There is an optimum aeration rate in the MBMBR process compartments. → Optimum aeration rate maximizes nutrients removal. → Optimum aeration rate minimizes membrane fouling. → Both aeration rates in MBBR and membrane compartment can affect on membrane permeability. - Abstract: In MBR processes, sufficient aeration is necessary to maintain sustainable flux and to retard membrane fouling. Membrane permeability, sludge characteristics, nutrient removal and biomass growth at various air flow rates in the membrane and moving bed biofilm reactor (MBBR) compartments were studied in a pilot plant. The highest nitrogen and phosphorous removal rates were found at MBBR aeration rates of 151 and 85 L h -1 and a specific aeration demand per membrane area (SAD m ) of 1.2 and 0.4m air 3 m -2 h -1 , respectively. A linear correlation was found between the amount of attached biofilm and the nutrient removal rate. The aeration rate in the MBBR compartment and SAD m significantly influenced the sludge characteristics and membrane permeability. The optimum combination of the aeration rate in the MBBR compartment and SAD m were 151 L h -1 and 0.8-1.2m air 3 m membrane -2 h -1 , respectively.

  3. Optimizing aeration rates for minimizing membrane fouling and its effect on sludge characteristics in a moving bed membrane bioreactor

    Energy Technology Data Exchange (ETDEWEB)

    Rahimi, Yousef, E-mail: yrahimi@ut.ac.ir [Department of Civil and Environmental Engineering, Graduate Faculty of Environment, University of Tehran, No. 25 Qods St., Enghelab Ave., Tehran (Iran, Islamic Republic of); Torabian, Ali, E-mail: atorabi@ut.ac.ir [Department of Civil and Environmental Engineering, Graduate Faculty of Environment, University of Tehran, No. 25 Qods St., Enghelab Ave., Tehran (Iran, Islamic Republic of); Mehrdadi, Naser, E-mail: mehrdadi@ut.ac.ir [Department of Civil and Environmental Engineering, Graduate Faculty of Environment, University of Tehran, No. 25 Qods St., Enghelab Ave., Tehran (Iran, Islamic Republic of); Habibi-Rezaie, Mehran, E-mail: mhabibi@khayam.ut.ac.ir [Department of Biotechnology, Faculty of Biology, College of Science, University of Tehran, No. 25 Qods St., Enghelab Ave., Tehran (Iran, Islamic Republic of); Pezeshk, Hamid, E-mail: pezeshk@khayam.ut.ac.ir [Department of Statistics, Faculty of Mathematics and Computer, College of Science, University of Tehran, No. 25 Qods St., Enghelab Ave., Tehran (Iran, Islamic Republic of); Nabi-Bidhendi, Gholam-Reza, E-mail: ghhendi@ut.ac.ir [Department of Civil and Environmental Engineering, Graduate Faculty of Environment, University of Tehran, No. 25 Qods St., Enghelab Ave., Tehran (Iran, Islamic Republic of)

    2011-02-28

    Research highlights: {yields} There is an optimum aeration rate in the MBMBR process compartments. {yields} Optimum aeration rate maximizes nutrients removal. {yields} Optimum aeration rate minimizes membrane fouling. {yields} Both aeration rates in MBBR and membrane compartment can affect on membrane permeability. - Abstract: In MBR processes, sufficient aeration is necessary to maintain sustainable flux and to retard membrane fouling. Membrane permeability, sludge characteristics, nutrient removal and biomass growth at various air flow rates in the membrane and moving bed biofilm reactor (MBBR) compartments were studied in a pilot plant. The highest nitrogen and phosphorous removal rates were found at MBBR aeration rates of 151 and 85 L h{sup -1} and a specific aeration demand per membrane area (SAD{sub m}) of 1.2 and 0.4m{sub air}{sup 3} m{sup -2} h{sup -1}, respectively. A linear correlation was found between the amount of attached biofilm and the nutrient removal rate. The aeration rate in the MBBR compartment and SAD{sub m} significantly influenced the sludge characteristics and membrane permeability. The optimum combination of the aeration rate in the MBBR compartment and SAD{sub m} were 151 L h{sup -1} and 0.8-1.2m{sub air}{sup 3}m{sub membrane}{sup -2} h{sup -1}, respectively.

  4. 46 CFR 169.627 - Compartments containing diesel fuel tanks.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Compartments containing diesel fuel tanks. 169.627... SCHOOL VESSELS Machinery and Electrical Ventilation § 169.627 Compartments containing diesel fuel tanks. Unless they are adequately ventilated, enclosed compartments or spaces containing diesel fuel tanks and...

  5. Radiation effects on bovine taste bud membranes

    International Nuclear Information System (INIS)

    Shatzman, A.R.; Mossman, K.L.

    1982-01-01

    In order to investigate the mechanisms of radiation-induced taste loss, the effects of radiation on preparations of enriched bovine taste bud membranes were studied. Taste buds containing circumvallate papilae, and surrounding control epithelial tissues devoid of taste buds, were obtained from steers and given radiation doses of 0-7000 cGy (rad). Tissue fractions were isolated into membrane-enriched and heterogeneous components using differential and sucrose gradient centrifugation of tissue homogenates. The yield of membranes, as measured by protein content in the buoyant membrane-enriched fractions, was reduced in quantity with increasing radiation dose. The relation between radiation dose and membrane quantity in membrane-enriched fractions could be fit by a simple exponential model with taste bud-derived membranes twice as radiosensitive as membranes from control epithelial tissue. Binding of sucrose, sodium, and acetate and fluoride stimulation of adenylate cyclase were nearly identical in both irradiated and nonirradiated intact membranes. Radiation had no effect on fractions of heterogeneous components. While it is not clear what changes are occurring in enriched taste cell membranes, damage to membranes may play an important role in the taste loss observed in patients following radiotherapy

  6. Enteral Feeding in Abdominal Compartment Syndrome

    Directory of Open Access Journals (Sweden)

    Ye. V Grigoryev

    2009-01-01

    Full Text Available Objective: to substantiate the choice of a gastrointestinal tract (GIT function support regimen as a mode for correction of the abdominal compartment syndrome (ACS. Subjects and methods. Forty-three patients with different causes of inadequate GIT function of various origin and ACS (disseminated peritonitis (45%, pancreatitis (24%, and severe concomitant injury (31% were examined. Group 1 (control received complete parenteral nutritional feeding (n=23; APACHE II scores, 21±4; calculated probability of fatal outcome, 33.5%. In Group II (study, complete parenteral feeding in the first 24 hours after stabilization was supplemented with GIT function support with Pepsisorb (Nutricia in doses of 500, 1000, and 1500 ml on days 1, 2, and 3, respectively (n=20; APACHE II scores, 20±6; calculated probability of fatal outcome, 37.1%. During early enteral nutritional support, the SOFA score was significantly less than that in Group 1 on days 2—3; the oxygenation index significantly increased on day 3; the value of intra-abdominal hypertension decreased to the control values. The positive effect of the GIT function support regimen on regression of the multiple organ dysfunction syndrome (MODS was confirmed by the lowered levels of biological markers (von Willebrand factor (WF and endothelin-1 as markers of endothelial damage of MODS. Correlation analysis showed a direct correlation between the markers of endothelial damage and the SOFA scores (r=0.34; p=0.05 for WF and r=0.49;p=0.03 for endothelin. Conclusion. The GIT function support regimen via early enteral alimentation with Peptisorb, which was initiated in the first 24 hours after admission, is able to level off the manifestations of the early stages of the abdominal compartment syndrome, with the acceptable values of oxygen balance and water-electrolyte and osmotic homeostasis being achieved. Key words: abdominal compartment syndrome, nutritional support, biological markers, oxygenation index

  7. Multi-compartment linear noise approximation

    International Nuclear Information System (INIS)

    Challenger, Joseph D; McKane, Alan J; Pahle, Jürgen

    2012-01-01

    The ability to quantify the stochastic fluctuations present in biochemical and other systems is becoming increasing important. Analytical descriptions of these fluctuations are attractive, as stochastic simulations are computationally expensive. Building on previous work, a linear noise approximation is developed for biochemical models with many compartments, for example cells. The procedure is then implemented in the software package COPASI. This technique is illustrated with two simple examples and is then applied to a more realistic biochemical model. Expressions for the noise, given in the form of covariance matrices, are presented. (paper)

  8. [Intraabdominal hypertension and abdominal compartment syndrome

    DEFF Research Database (Denmark)

    Sonne, M.; Hilligsø, Jens Georg

    2008-01-01

    Intraabdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are rare conditions with high mortality. IAH is an intraabdominal pressure (IAP) above 12 mmHg and ACS an IAP above 20 mmHg with evidence of organ dysfunction. IAP is measured indirectly via the bladder or stomach. Various...... medical and surgical conditions increase the intraabdominal volume. When the content exceeds the compliance of the abdominal wall, the IAP rises. Increased IAP affects the functioning of the brain, lungs, circulation, kidneys, and bowel. The treatment of ACS is a reduction of IAP Udgivelsesdato: 2008/2/11...

  9. Transcytosis of immunoglobulin A in the mouse enterocyte occurs through glycolipid raft- and rab17-containing compartments

    DEFF Research Database (Denmark)

    Hansen, Gert Helge; Niels-Christiansen, L L; Immerdal, Lissi

    1999-01-01

    BACKGROUND & AIMS: Glycolipid "rafts" have been shown to play a role in apical membrane trafficking in the enterocyte. The present study characterized the membrane compartments of the enterocyte involved in transepithelial transport of small intestinal immunoglobulin A (IgA). Methods: Immunogold...... electron microscopy and radioactive labeling of mouse small intestinal explants were performed. RESULTS: IgA and the polymeric immunoglobulin receptor/secretory component were present in a raft compartment. Raft association occurred posttranslationally within 30 minutes, preceding secretion...... and were also frequently seen associated with the same vesicular profiles of glycolipid rafts. Colocalization of IgA and rab17, a small guanosine triphosphatase involved in transcytosis, was seen mainly along the basolateral plasma membrane and over basolateral endosomes and vesicles, but also...

  10. Membrane domains and polarized trafficking of sphingolipids

    NARCIS (Netherlands)

    Maier, O; Slimane, TA; Hoekstra, D

    The plasma membrane of polarized cells consists of distinct domains, the apical and basolateral membrane that are characterized by a distinct lipid and protein content. Apical protein transport is largely mediated by (glyco)sphingolipid-cholesterol enriched membrane microdomains, so called rafts. In

  11. Derived enriched uranium market

    International Nuclear Information System (INIS)

    Rutkowski, E.

    1996-01-01

    The potential impact on the uranium market of highly enriched uranium from nuclear weapons dismantling in the Russian Federation and the USA is analyzed. Uranium supply, conversion, and enrichment factors are outlined for each country; inventories are also listed. The enrichment component and conversion components are expected to cause little disruption to uranium markets. The uranium component of Russian derived enriched uranium hexafluoride is unresolved; US legislation places constraints on its introduction into the US market

  12. Porcine reproductive and respiratory syndrome virus nonstructural protein 2 (nsp2) topology and selective isoform integration in artificial membranes

    Science.gov (United States)

    Membrane modification of host subcellular compartments is critical to the replication of many RNA viruses. Enveloped viruses additionally require the ability to requisition cellular membranes during egress for the development of infectious progeny. Porcine reproductive and respiratory syndrome virus...

  13. Uranium enrichment plans

    International Nuclear Information System (INIS)

    Thomas, D.C.; Gagne, R.W.

    1978-01-01

    The following topics are covered: the status of the Government's existing uranium enrichment services contracts, natural uranium requirements based on the latest contract information, uncertainty in predicting natural uranium requirements based on uranium enrichment contracts, and domestic and foreign demand assumed in enrichment planning

  14. Electrolytic process to produce sodium hypochlorite using sodium ion conductive ceramic membranes

    Science.gov (United States)

    Balagopal, Shekar; Malhotra, Vinod; Pendleton, Justin; Reid, Kathy Jo

    2012-09-18

    An electrochemical process for the production of sodium hypochlorite is disclosed. The process may potentially be used to produce sodium hypochlorite from seawater or low purity un-softened or NaCl-based salt solutions. The process utilizes a sodium ion conductive ceramic membrane, such as membranes based on NASICON-type materials, in an electrolytic cell. In the process, water is reduced at a cathode to form hydroxyl ions and hydrogen gas. Chloride ions from a sodium chloride solution are oxidized in the anolyte compartment to produce chlorine gas which reacts with water to produce hypochlorous and hydrochloric acid. Sodium ions are transported from the anolyte compartment to the catholyte compartment across the sodium ion conductive ceramic membrane. Sodium hydroxide is transported from the catholyte compartment to the anolyte compartment to produce sodium hypochlorite within the anolyte compartment.

  15. Phosphorous recovery from sewage sludge ash suspended in water in a two-compartment electrodialytic cell

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Jensen, Pernille Erland; Kirkelund, Gunvor Marie

    2016-01-01

    was suspended in water in the anolyte, which was separated from the catholyte by a cation exchange membrane. Electrolysis at the anode acidified the SSA suspension, and hereby P, Cu, Pb, Cd and Zn were extracted. The heavy metal ions electromigrated into the catholyte and were thus separated from the filtrate......Phosphorus (P) is indispensable for all forms of life on Earth and as P is a finite resource, it is highly important to increase recovery of P from secondary resources. This investigation is focused on P recovery from sewage sludge ash (SSA) by a two-compartment electrodialytic separation (EDS......) technique. Two SSAs are included in the investigation and they contained slightly less P than phosphate rock used in commercial fertilizer production and more heavy metals. The two-compartment electrodialytic technique enabled simultaneous recovery of P and separation of heavy metals. During EDS the SSA...

  16. Uranium Enrichment, an overview

    International Nuclear Information System (INIS)

    Coates, J.H.

    1994-01-01

    This general presentation on uranium enrichment will be followed by lectures on more specific topics including descriptions of enrichment processes and assessments of the prevailing commercial and industrial situations. I shall therefore avoid as much as possible duplications with these other lectures, and rather dwell on: some theoretical aspects of enrichment in general, underlying the differences between statistical and selective processes, a review and comparison between enrichment processes, remarks of general order regarding applications, the proliferation potential of enrichment. It is noteworthy that enrichment: may occur twice in the LWR fuel cycle: first by enriching natural uranium, second by reenriching uranium recovered from reprocessing, must meet LWR requirements, and in particular higher assays required by high burn up fuel elements, bears on the structure of the entire front part of the fuel cycle, namely in the conversion/reconversion steps only involving UF 6 for the moment. (author). tabs., figs., 4 refs

  17. 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...... for the lateral organization of membranes as wells as for physical properties like bending, permeability and elasticity...

  18. Modeling malware propagation using a carrier compartment

    Science.gov (United States)

    Hernández Guillén, J. D.; Martín del Rey, A.

    2018-03-01

    The great majority of mathematical models proposed to simulate malware spreading are based on systems of ordinary differential equations. These are compartmental models where the devices are classified according to some types: susceptible, exposed, infectious, recovered, etc. As far as we know, there is not any model considering the special class of carrier devices. This type is constituted by the devices whose operative systems is not targeted by the malware (for example, iOS devices for Android malware). In this work a novel mathematical model considering this new compartment is considered. Its qualitative study is presented and a detailed analysis of the efficient control measures is shown by studying the basic reproductive number.

  19. The upper hand on compartment syndrome.

    LENUS (Irish Health Repository)

    Dolan, Roisin T

    2012-11-01

    Metacarpal fractures are common injuries, accounting for approximately 30% to 40% of all hand fractures and with a lifetime incidence of 2.5%. Traditionally regarded as an innocuous injury, metacarpal fractures tend to be associated with successful outcomes after closed reduction and immobilization. Hand compartment syndrome (HCS) is a rare clinical entity with potential devastating consequences in terms of loss of function and quality-of-life outcomes. We discuss the case of a 44-year-old woman presenting with multiple closed metacarpal fractures as a result of low-energy trauma, complicated by acute HCS. We review the presentation, clinical assessment, and optimal surgical management of acute HCS with reference to international literature.

  20. An experimental study on crib fires in a closed compartment

    Directory of Open Access Journals (Sweden)

    Dhurandher Bhisham Kumar

    2017-01-01

    Full Text Available An experimental investigation on burning behavior of fire in closed compartments is presented. Fire experiments were performed in a closed compartment of interior dimensions 4 × 4 × 4 m (length × width × height with ply board cribs as fire source. The parameters including the gas temperature, mass loss rate, heat flux, flame temperature, and compartment pressure were measured during the experiments. Experimental results indicated that the providing sudden ventilation to the closed compartment had great influence on the behavior of fire. The mass loss rate of the burning crib increased by 150% due to sudden ventilation which results in the increase in heat release rate by 198 kW. From the perspective of total heat flux, compartment pressure, and gas temperatures closed compartment with sudden ventilation were more hazardous.

  1. NMR quantification of diffusional exchange in cell suspensions with relaxation rate differences between intra and extracellular compartments.

    Science.gov (United States)

    Eriksson, Stefanie; Elbing, Karin; Söderman, Olle; Lindkvist-Petersson, Karin; Topgaard, Daniel; Lasič, Samo

    2017-01-01

    Water transport across cell membranes can be measured non-invasively with diffusion NMR. We present a method to quantify the intracellular lifetime of water in cell suspensions with short transverse relaxation times, T2, and also circumvent the confounding effect of different T2 values in the intra- and extracellular compartments. Filter exchange spectroscopy (FEXSY) is specifically sensitive to exchange between compartments with different apparent diffusivities. Our investigation shows that FEXSY could yield significantly biased results if differences in T2 are not accounted for. To mitigate this problem, we propose combining FEXSY with diffusion-relaxation correlation experiment, which can quantify differences in T2 values in compartments with different diffusivities. Our analysis uses a joint constrained fitting of the two datasets and considers the effects of diffusion, relaxation and exchange in both experiments. The method is demonstrated on yeast cells with and without human aquaporins.

  2. A human cadaver fascial compartment pressure measurement model.

    Science.gov (United States)

    Messina, Frank C; Cooper, Dylan; Huffman, Gretchen; Bartkus, Edward; Wilbur, Lee

    2013-10-01

    Fresh human cadavers provide an effective model for procedural training. Currently, there are no realistic models to teach fascial compartment pressure measurement. We created a human cadaver fascial compartment pressure measurement model and studied its feasibility with a pre-post design. Three faculty members, following instructions from a common procedure textbook, used a standard handheld intra-compartment pressure monitor (Stryker(®), Kalamazoo, MI) to measure baseline pressures ("unembalmed") in the anterior, lateral, deep posterior, and superficial posterior compartments of the lower legs of a fresh human cadaver. The right femoral artery was then identified by superficial dissection, cannulated distally towards the lower leg, and connected to a standard embalming machine. After a 5-min infusion, the same three faculty members re-measured pressures ("embalmed") of the same compartments on the cannulated right leg. Unembalmed and embalmed readings for each compartment, and baseline readings for each leg, were compared using a two-sided paired t-test. The mean baseline compartment pressures did not differ between the right and left legs. Using the embalming machine, compartment pressure readings increased significantly over baseline for three of four fascial compartments; all in mm Hg (±SD): anterior from 40 (±9) to 143 (±44) (p = 0.08); lateral from 22 (±2.5) to 160 (±4.3) (p cadaver using a standard embalming machine. Set-up is minimal and the model can be incorporated into teaching curricula. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Advanced enrichment techniques

    International Nuclear Information System (INIS)

    Johnson, A.

    1988-01-01

    BNFL is in a unique position in that it has commercial experience of diffusion enrichment, and of centrifuge enrichment through its associate company Urenco. In addition BNFL is developing laser enrichment techniques as part of a UK development programme in this area. The paper describes the development programme which led to the introduction of competitive centrifuge enrichment technology by Urenco and discusses the areas where improvements have and will continue to be made in the centrifuge process. It also describes the laser development programme currently being undertaken in the UK. The paper concludes by discussing the relative merits of the various methods of uranium enrichment, with particular reference to the enrichment market likely to obtain over the rest of the century

  4. Advanced enrichment techniques

    International Nuclear Information System (INIS)

    Johnson, A.

    1987-01-01

    BNFL is in a unique position in that it has commercial experience of diffusion enrichment, and of centrifuge enrichment through its associate company Urenco. In addition BNFL is developing laser enrichment techniques as part of a UK development programme in this area. The paper describes the development programme which led to the introduction of competitive centrifuge enrichment technology by Urenco and discusses the areas where improvements have and will continue to be made in the centrifuge process. It also describes the laser development programme currently being undertaken in the UK. The paper concludes by discussing the relative merits of the various methods of uranium enrichment, with particular reference to the enrichment market likely to obtain over the rest of the century. (author)

  5. Uranium enrichment: an overview

    International Nuclear Information System (INIS)

    Cazalet, J.

    1995-01-01

    This paper is a general presentation of uranium enrichment processes and assessments of the prevailing commercial and industrial situations. It gives first some theoretical aspects of enrichment in general and explains the differences between statistical and selective processes in particular. Then a review of the different processes is made with a comparison between them. Finally, some general remarks concerning applications are given and the risks of proliferation related to enrichment are mentioned. (J.S.). 4 refs., 5 figs., 8 tabs

  6. The enrichment secondary market

    International Nuclear Information System (INIS)

    Einbund, D.R.

    1986-01-01

    This paper will addresses two topics: the background to the present status of the enrichment secondary market and the future outlook of the secondary market in enrichment services, and the viability of the nuclear fuel brokerage industry. These two topics are inevitably connected, as most secondary market activity, not only in enrichment but also in natural uranium, has traditionally been conducted with the participation of brokers. Therefore, the author interrelates these topics

  7. Mechanics of Lipid Bilayer Membranes

    Science.gov (United States)

    Powers, Thomas R.

    All cells have membranes. The plasma membrane encapsulates the cell's interior, acting as a barrier against the outside world. In cells with nuclei (eukaryotic cells), membranes also form internal compartments (organelles) which carry out specialized tasks, such as protein modification and sorting in the case of the Golgi apparatus, and ATP production in the case of mitochondria. The main components of membranes are lipids and proteins. The proteins can be channels, carriers, receptors, catalysts, signaling molecules, or structural elements, and typically contribute a substantial fraction of the total membrane dry weight. The equilibrium properties of pure lipid membranes are relatively well-understood, and will be the main focus of this article. The framework of elasticity theory and statistical mechanics that we will develop will serve as the foundation for understanding biological phenomena such as the nonequilibrium behavior of membranes laden with ion pumps, the role of membrane elasticity in ion channel gating, and the dynamics of vesicle fission and fusion. Understanding the mechanics of lipid membranes is also important for drug encapsulation and delivery.

  8. Simulating Isotope Enrichment by Gaseous Diffusion

    Science.gov (United States)

    Reed, Cameron

    2015-04-01

    A desktop-computer simulation of isotope enrichment by gaseous diffusion has been developed. The simulation incorporates two non-interacting point-mass species whose members pass through a cascade of cells containing porous membranes and retain constant speeds as they reflect off the walls of the cells and the spaces between holes in the membranes. A particular feature is periodic forward recycling of enriched material to cells further along the cascade along with simultaneous return of depleted material to preceding cells. The number of particles, the mass ratio, the initial fractional abundance of the lighter species, and the time between recycling operations can be chosen by the user. The simulation is simple enough to be understood on the basis of two-dimensional kinematics, and demonstrates that the fractional abundance of the lighter-isotope species increases along the cascade. The logic of the simulation will be described and results of some typical runs will be presented and discussed.

  9. Lysosomal degradation of membrane lipids.

    Science.gov (United States)

    Kolter, Thomas; Sandhoff, Konrad

    2010-05-03

    The constitutive degradation of membrane components takes place in the acidic compartments of a cell, the endosomes and lysosomes. Sites of lipid degradation are intralysosomal membranes that are formed in endosomes, where the lipid composition is adjusted for degradation. Cholesterol is sorted out of the inner membranes, their content in bis(monoacylglycero)phosphate increases, and, most likely, sphingomyelin is degraded to ceramide. Together with endosomal and lysosomal lipid-binding proteins, the Niemann-Pick disease, type C2-protein, the GM2-activator, and the saposins sap-A, -B, -C, and -D, a suitable membrane lipid composition is required for degradation of complex lipids by hydrolytic enzymes. Copyright 2009 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  10. Abdominal Compartment Syndrome Secondary to Chronic Constipation

    Directory of Open Access Journals (Sweden)

    Helene Flageole

    2011-01-01

    Full Text Available Abdominal compartment syndrome (ACS is defined as an elevated intraabdominal pressure with evidence of organ dysfunction. The majority of published reports of ACS are in neonates with abdominal wall defects and in adults following trauma or burns, but it is poorly described in children. We describe the unusual presentation of an 11-year-old boy with a long history of chronic constipation who developed acute ACS requiring resuscitative measures and emergent disimpaction. He presented with a 2-week history of increasing abdominal pain, nausea, diminished appetite and longstanding encopresis. On exam, he was emaciated with a massively distended abdomen with a palpable fecaloma. Abdominal XR confirmed these findings. Within 24 hours of presentation, he became tachycardic and oliguric with orthostatic hypotension. Following two enemas, he acutely deteriorated with severe hypotension, marked tachycardia, acute respiratory distress, and a declining mental status. Endotracheal intubation, fluid boluses, and vasopressors were commenced, followed by emergent surgical fecal disimpaction. This resulted in rapid improvement in vital signs. He has been thoroughly investigated and no other condition apart from functional constipation has been identified. Although ACS secondary to constipation is extremely unusual, this case illustrates the need to actively treat constipation and what can happen if it is not.

  11. Measuring Compartment Size and Gas Solubility in Marine Mammals

    Science.gov (United States)

    2015-09-30

    bends? Effect of diving behaviour and physiology on modelled gas exchange for three species: Ziphius cavirostris, Mesoplodon densirostris and Hyperoodon...1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Measuring Compartment Size and Gas Solubility in Marine...is to develop methods to estimate marine mamal tissue compartment sizes, and tissue gas solubility. We aim to improve the data available for the

  12. [Progress of midfacial fat compartments and related clinical applications].

    Science.gov (United States)

    Wen, Lihong; Wang, Jinhuang; Li, Yang; Liu, Dalie

    2018-02-01

    To review the research progress of midfacial fat compartments, and to thoroughly understand its current state of the anatomy and the aging morphologic characters of midfacial fat compartments, as well as the current status of clinical applications. The recent literature concerning the midfacial fat compartments and related clinical applications were extensively reviewed and analyzed. Midfacial fat layer has been considered as a fusion and a continuous layer, experiencing a global atrophy when aging. As more anatomical researches have done, recent studies have shown that midfacial fat layer is broadly divided into superficial and deep layers, which are both divided into different fat compartments by fascia, ligaments, or muscles. Midfacial fat compartments tend to atrophy with age, specifically in the deep fat compartments while hypertrophy in the superficial fat compartments. Clinical applications show that fat volumetric restoration with deep medial cheek fat and Ristow's space can restore the appearance of midface effectively. In recent years, the researches of midfacial fat compartments have achieved obvious progress, which will provide new ideas and basis for fat volumetric restoration. Corresponding treatments are selected based on different sites and different layers with different aging changes, reshaping a more youthful midface.

  13. Multi-compartment Fire Modeling for Switchgear Room using CFAST

    International Nuclear Information System (INIS)

    Han, Kiyoon; Kang, Dae Il; Lim, Ho Gon

    2015-01-01

    In this study, multi-compartment fire modeling for fire propagation scenario from SWGR A to SWGR B is performed using CFAST. New fire PSA method (NUREG/CR-6850) requires that the severity factor is to be calculated by fire modeling. If fire modeling is not performed, the severity factor should be estimated as one conservatively. Also, the possibility of the damages of components and cables located at adjacent compartments should be considered. Detailed fire modeling of multi-compartment fires refers to the evaluation of fire-generated conditions in one compartment that spread to adjacent ones. In general, the severity factor for multi-compartment fire scenario is smaller than that of single compartment scenario. Preliminary quantification of Hanul Unit 3 fire PSA was performed without fire modeling. As a result of quantification, multi-compartment scenario, fire propagation scenario from switchgear room (SWGR) A to SWGR B, is one of significant contributor to the CDF. In this study, fire modeling of multi-compartment was performed by Consolidated Fire Growth and Smoke Transport (CFAST) to identify the possibility of fire propagation. As a result of fire simulation, it is identified that fire propagation has little influences

  14. Multi-compartment Fire Modeling for Switchgear Room using CFAST

    Energy Technology Data Exchange (ETDEWEB)

    Han, Kiyoon; Kang, Dae Il; Lim, Ho Gon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    In this study, multi-compartment fire modeling for fire propagation scenario from SWGR A to SWGR B is performed using CFAST. New fire PSA method (NUREG/CR-6850) requires that the severity factor is to be calculated by fire modeling. If fire modeling is not performed, the severity factor should be estimated as one conservatively. Also, the possibility of the damages of components and cables located at adjacent compartments should be considered. Detailed fire modeling of multi-compartment fires refers to the evaluation of fire-generated conditions in one compartment that spread to adjacent ones. In general, the severity factor for multi-compartment fire scenario is smaller than that of single compartment scenario. Preliminary quantification of Hanul Unit 3 fire PSA was performed without fire modeling. As a result of quantification, multi-compartment scenario, fire propagation scenario from switchgear room (SWGR) A to SWGR B, is one of significant contributor to the CDF. In this study, fire modeling of multi-compartment was performed by Consolidated Fire Growth and Smoke Transport (CFAST) to identify the possibility of fire propagation. As a result of fire simulation, it is identified that fire propagation has little influences.

  15. Uranium enrichment plans

    International Nuclear Information System (INIS)

    Gagne, R.W.; Thomas, D.C.

    1977-01-01

    The status of existing uranium enrichment contracts in the US is reviewed and expected natural uranium requirements for existing domestic uranium enrichment contracts are evaluated. Uncertainty in natural uranium requirements associated with requirements-type and fixed-commitment type contracts is discussed along with implementation of variable tails assay

  16. Compartment in vertical flow reactor for ferruginous mine water

    Science.gov (United States)

    Hur, Won; Cheong, Young-Wook; Yim, Gil-Jae; Ji, Sang-Woo; Hong, Ji-Hye

    2014-05-01

    Mine effluents contain varying concentrations of ferrous ion along with other metal ions. Fe(II) that quickly oxidizes to form precipitates in the presence of oxygen under net alkaline or neutral conditions. Thus, passive treatment methods are designed for the mine water to reside in an open containment area so as to allow simultaneous oxidation and precipitation of Fe(II), such as in a lagoon or an oxidation pond. A vertical flow reactor (VFR) was also suggested to remediate ferruginous mine drainage passing down through an accreting bed of ochre. However, VFR has a limited operation time until the system begins to overflow. It was also demonstrated that two-compartment VFR has a longer operation time than single compartment VFR of same size. In this study, a mathematical model was developed as a part of efforts to explore the operation of VFR, showing dynamic changes in head differences, ochre depth and Fe(II)/Fe(III) concentration in the effluent flow. The analysis shows that Fe(II) oxidation and ochre formation should be balanced with permeability of ochre bed to maximize VFR operation time and minimize residual Fe(II) in the effluent. The model demonstrates that two compartment VFR can have a longer operation time than a single-compartment VFR and that an optimum compartment ratio exists that maximize VFR operation time. Accelerated Fe(II) oxidation significantly affects the optimum ratio of compartment area and reduced residual Fe(II) in the effluent. VFR operation time can be significantly prolonged by increasing the rate of ochre formation not by accelerated Fe(II) oxidation. Taken together, ochre forms largely in the first compartment while overflowed mine water with reduced iron contents is efficiently filtered in the second compartment. These results provide us a better understanding of VFR operation and optimum design criteria for maximum operation time in a two-compartment VFR. Rapid ochre accretion in the first compartment maintains constant hydraulic

  17. Organic Pollutant Penetration through Fruit Polyester Skin: A Modified Three-compartment Diffusion Model.

    Science.gov (United States)

    Li, Yungui; Li, Qingqing; Chen, Baoliang

    2016-03-24

    The surface of plants is covered by a continuous but heterogeneous cuticular membrane (CM). Serving as the first protective barrier, the uptake and transport behavior of organic pollutants at this interface continue to engage the research efforts of environmental chemist. To date, the contributions of cuticular components as a defense against the organic pollutants penetration remain unresolved. In this study, the unsteady-state penetration characteristics of phenanthrene (PHE) through isolated fruit CM was investigated. PHE penetration was differentiated by three cuticular compartments: epicuticular waxes (EW), cuticle proper (CP) and cuticular layer (CL). The driving force for PHE penetration was ascribed to the sharp concentration gradient built up endogenously by cuticular compartments with different lipophilic affinities. A modified penetration model was established and verified in terms of its general suitability for the hydrophobic chemicals and CMs of various plant species (apple, tomato and potato). The new three-compartment model demonstrates much higher accuracy in characterizing the uptake and transport behavior of semivolatile chemicals with fewer limitations in terms of environmental conditions and complexity (e.g., coexisting contaminants and temperature). This model could contribute to a more comprehensive understanding on the role of polymeric lipids in the organic pollutant sorption and transport into plants.

  18. TLR2 ligands induce NF-κB activation from endosomal compartments of human monocytes.

    Directory of Open Access Journals (Sweden)

    Karim J Brandt

    Full Text Available Localization of Toll-like receptors (TLR in subcellular organelles is a major strategy to regulate innate immune responses. While TLR4, a cell-surface receptor, signals from both the plasma membrane and endosomal compartments, less is known about the functional role of endosomal trafficking upon TLR2 signaling. Here we show that the bacterial TLR2 ligands Pam3CSK4 and LTA activate NF-κB-dependent signaling from endosomal compartments in human monocytes and in a NF-κB sensitive reporter cell line, despite the expression of TLR2 at the cell surface. Further analyses indicate that TLR2-induced NF-κB activation is controlled by a clathrin/dynamin-dependent endocytosis mechanism, in which CD14 serves as an important upstream regulator. These findings establish that internalization of cell-surface TLR2 into endosomal compartments is required for NF-κB activation. These observations further demonstrate the need of endocytosis in the activation and regulation of TLR2-dependent signaling pathways.

  19. Wrist arthrography: The value of the three compartment injection technique

    Energy Technology Data Exchange (ETDEWEB)

    Levinsohn, E.M.; Coren, A.B.; Palmer, A.K.; Zinberg, E.

    1987-10-01

    Arthrography of the wrist was performed on 50 consecutive patients with obscure post-traumatic wrist pain by injecting contrast separately into the radiocarpal joint, midcarpal compartment, and distal radioulnar joint. When distal radioulnar joint and midcarpal compartment injections were added to the standard radiocarpal injection, many significant unsuspected abnormalities were identified. Of the 25 triangular fibrocartilage complex abnormalities identified, six (24%) were found only with the distal radioulnar joint injection. Of the 29 abnormal communications between the midcarpal compartment and the radiocarpal joint, ten (35%) were found only with the midcarpal injection. Similarly, five of 29 (17%) of the abnormal radiocarpal-midcarpal communications would have been missed if a midcarpal injection alone had been performed. These findings indicate that separate injections into the radiocarpal joint, midcarpal compartment, and distal radioulnar joint are needed to identify a large number of abnormalities not seen with injections into one compartment alone.

  20. Computation of thermal comfort inside a passenger car compartment

    International Nuclear Information System (INIS)

    Mezrhab, A.; Bouzidi, M.

    2006-01-01

    This paper describes a numerical model to study the behaviour of thermal comfort inside the passenger car compartment according to climatic conditions and materials that compose the vehicle. The specifically developed numerical model is based on the nodal method and the finite difference method. Its specificities are: (i) the transient mode, (ii) the taking into account of the combined convection, conduction and radiation heat transfer, (iii) the coupling of two spectral bands (short-wave and long-wave radiation) and two solar fluxes (beam and diffuse). The compartment is subdivided in several solid nodes (materials constituting the compartment) and fluid nodes (volumes of air inside the compartment). The establishment of the heat balance for each node gives the evolution of its temperature. Effects of solar radiation, types of glazing, car colour and radiative properties of materials constituting the compartment are investigated

  1. Host ESCRT proteins are required for bromovirus RNA replication compartment assembly and function.

    Directory of Open Access Journals (Sweden)

    Arturo Diaz

    2015-03-01

    Full Text Available Positive-strand RNA viruses genome replication invariably is associated with vesicles or other rearranged cellular membranes. Brome mosaic virus (BMV RNA replication occurs on perinuclear endoplasmic reticulum (ER membranes in ~70 nm vesicular invaginations (spherules. BMV RNA replication vesicles show multiple parallels with membrane-enveloped, budding retrovirus virions, whose envelopment and release depend on the host ESCRT (endosomal sorting complexes required for transport membrane-remodeling machinery. We now find that deleting components of the ESCRT pathway results in at least two distinct BMV phenotypes. One group of genes regulate RNA replication and the frequency of viral replication complex formation, but had no effect on spherule size, while a second group of genes regulate RNA replication in a way or ways independent of spherule formation. In particular, deleting SNF7 inhibits BMV RNA replication > 25-fold and abolishes detectable BMV spherule formation, even though the BMV RNA replication proteins accumulate and localize normally on perinuclear ER membranes. Moreover, BMV ESCRT recruitment and spherule assembly depend on different sets of protein-protein interactions from those used by multivesicular body vesicles, HIV-1 virion budding, or tomato bushy stunt virus (TBSV spherule formation. These and other data demonstrate that BMV requires cellular ESCRT components for proper formation and function of its vesicular RNA replication compartments. The results highlight growing but diverse interactions of ESCRT factors with many viruses and viral processes, and potential value of the ESCRT pathway as a target for broad-spectrum antiviral resistance.

  2. HIV-1 Envelope Glycoprotein Trafficking through the Endosomal Recycling Compartment Is Required for Particle Incorporation.

    Science.gov (United States)

    Kirschman, Junghwa; Qi, Mingli; Ding, Lingmei; Hammonds, Jason; Dienger-Stambaugh, Krista; Wang, Jaang-Jiun; Lapierre, Lynne A; Goldenring, James R; Spearman, Paul

    2018-03-01

    The human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein (Env) encodes specific trafficking signals within its long cytoplasmic tail (CT) that regulate incorporation into HIV-1 particles. Rab11-family interacting protein 1C (FIP1C) and Rab14 are host trafficking factors required for Env particle incorporation, suggesting that Env undergoes sorting from the endosomal recycling compartment (ERC) to the site of particle assembly on the plasma membrane. We disrupted outward sorting from the ERC by expressing a C-terminal fragment of FIP1C (FIP1C 560-649 ) and examined the consequences on Env trafficking and incorporation into particles. FIP1C 560-649 reduced cell surface levels of Env and prevented its incorporation into HIV-1 particles. Remarkably, Env was trapped in an exaggerated perinuclear ERC in a CT-dependent manner. Mutation of either the Yxxϕ endocytic motif or the YW 795 motif in the CT prevented Env trapping in the ERC and restored incorporation into particles. In contrast, simian immunodeficiency virus SIVmac239 Env was not retained in the ERC, while substitution of the HIV-1 CT for the SIV CT resulted in SIV Env retention in this compartment. These results provide the first direct evidence that Env traffics through the ERC and support a model whereby HIV-1 Env is specifically targeted to the ERC prior to FIP1C- and CT-dependent outward sorting to the particle assembly site on the plasma membrane. IMPORTANCE The HIV envelope protein is an essential component of the viral particle. While many aspects of envelope protein structure and function have been established, the pathway it follows in the cell prior to reaching the site of particle assembly is not well understood. The envelope protein has a very long cytoplasmic tail that interacts with the host cell trafficking machinery. Here, we utilized a truncated form of the trafficking adaptor FIP1C protein to arrest the intracellular transport of the envelope protein, demonstrating that it becomes

  3. Autologous Chondrocyte Implantation for Bipolar Chondral Lesions in the Tibiofemoral Compartment.

    Science.gov (United States)

    Ogura, Takahiro; Bryant, Tim; Mosier, Brian A; Minas, Tom

    2018-05-01

    Treating bipolar chondral lesions in the tibiofemoral (TF) compartment with cartilage repair procedures is challenging, and a suitable treatment remains unclear. To evaluate clinical outcomes after autologous chondrocyte implantation (ACI) for the treatment of bipolar chondral lesions in the TF compartment. Case series; Level of evidence, 4. We evaluated 57 patients who underwent ACI for the treatment of symptomatic bipolar chondral lesions in the TF compartment by a single surgeon between October 1995 and June 2014. One patient did not return for follow-up. Thus, 56 patients (58 knees) were included with a minimum of 2 years' follow-up. A mean of 3.1 lesions per knee were treated, representing a mean total surface area of 16.1 cm 2 (range, 3.2-44.5 cm 2 ) per knee. Bipolar lesions were present in the medial compartment (32 knees) and in the lateral compartment (26 knees). Patients were evaluated with the modified Cincinnati Knee Rating Scale, visual analog scale for pain, Western Ontario and McMaster Universities Osteoarthritis Index, and Short Form-36. Patients also answered questions regarding self-rated knee function and satisfaction with the procedure. Standard radiographs were evaluated with the Kellgren-Lawrence grading system. The survival rate was 80% at 5 years and 76% at 10 years. A significantly better survival rate was found in patients with the use of a collagen membrane than periosteum (97% vs 61% at 5 years, respectively; P = .0014). Of 46 knees with retained grafts, all functional scores significantly improved postoperatively, with a very high satisfaction rate (91%) at a mean of 8.3 ± 5.1 years (range, 2-20 years) after ACI. At last follow-up, 24 of 46 successful knees were radiographically assessed (mean, 5.5 ± 4.0 years [range, 2.0-18.7 years]) and showed no significant osteoarthritis progression ( P = .3173). Outcomes for 12 patients were considered as failures at a mean of 4.1 years. Of these, 9 patients were converted to partial or total

  4. Functional outcome of tibial fracture with acute compartment syndrome and correlation to deep posterior compartment pressure.

    Science.gov (United States)

    Goyal, Saumitra; Naik, Monappa A; Tripathy, Sujit Kumar; Rao, Sharath K

    2017-05-18

    To measure single baseline deep posterior compartment pressure in tibial fracture complicated by acute compartment syndrome (ACS) and to correlate it with functional outcome. Thirty-two tibial fractures with ACS were evaluated clinically and the deep posterior compartment pressure was measured. Urgent fasciotomy was needed in 30 patients. Definite surgical fixation was performed either primarily or once fasciotomy wound was healthy. The patients were followed up at 3 mo, 6 mo and one year. At one year, the functional outcome [lower extremity functional scale (LEFS)] and complications were assessed. Three limbs were amputated. In remaining 29 patients, the average times for clinical and radiological union were 25.2 ± 10.9 wk (10 to 54 wk) and 23.8 ± 9.2 wk (12 to 52 wk) respectively. Nine patients had delayed union and 2 had nonunion who needed bone grafting to augment healing. Most common complaint at follow up was ankle stiffness (76%) that caused difficulty in walking, running and squatting. Of 21 patients who had paralysis at diagnosis, 13 (62%) did not recover and additional five patients developed paralysis at follow-up. On LEFS evaluation, there were 14 patients (48.3%) with severe disability, 10 patients (34.5%) with moderate disability and 5 patients (17.2%) with minimal disability. The mean pressures in patients with minimal disability, moderate disability and severe disability were 37.8, 48.4 and 58.79 mmHg respectively ( P fractures causes severe functional disability in majority of patients. These patients are prone for delayed union and nonunion; however, long term disability is mainly because of severe soft tissue contracture. Intra-compartmental pressure (ICP) correlates with functional disability; patients with relatively high ICP are prone for poor functional outcome.

  5. Trace elements distribution in environmental compartments

    International Nuclear Information System (INIS)

    Queiroz, Juliana C. de; Peres, Sueli da Silva; Godoy, Maria Luiza D.P.

    2017-01-01

    Trace elements term defines the presence of low concentrations metals at environment. Some of them are considered biologically essential, as Co, Cu and Mn. Others can cause detriment to environment and human health, as Pb, Cd, Hg, As, Ti and U. A large number of them have radioactive isotopes, implying the evaluation of risks for human health should be done considering the precepts of environmental radiological protection. The ecosystem pollution with trace elements generates changes at the geochemistry cycle of these elements and in environmental quality. Soils have single characteristics when compared with another components of biosphere (air, water and biota), cause they introduce themselves not only as a drain towards contaminants, but also as natural buffer that control the transport of chemical elements and other substances for atmosphere, hydrosphere and biota. The main purpose of environmental monitoring program is to evaluate the levels of contaminants in the various compartments of the environment: natural or anthropogenic, and to assess the contribution of a potential contaminant source on the environment. Elemental Composition for the collected samples was determined by inductively coupled plasma mass spectroscopy. The main objective of this work was to evaluate the map baseline of concentration of interest trace elements in environmental samples of water, sediment and soil from Environmental Monitoring Program of Instituto de Radioprotecao e Dosimetria (IRD). The samples were analyzed using an inductively coupled plasma mass spectrometer (ICP-MS) at IRD. >From the knowledge of trace elements concentrations, could be evaluated the environmental quality parameters at the studied ecosystems. The data allowed evaluating some relevant aspects of the study of trace elements in soil and aquatic systems, with emphasis at the distribution, concentration and identification of main anthropic sources of contamination at environment. (author)

  6. Trace elements distribution in environmental compartments

    Energy Technology Data Exchange (ETDEWEB)

    Queiroz, Juliana C. de; Peres, Sueli da Silva; Godoy, Maria Luiza D.P., E-mail: suelip@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2017-11-01

    Trace elements term defines the presence of low concentrations metals at environment. Some of them are considered biologically essential, as Co, Cu and Mn. Others can cause detriment to environment and human health, as Pb, Cd, Hg, As, Ti and U. A large number of them have radioactive isotopes, implying the evaluation of risks for human health should be done considering the precepts of environmental radiological protection. The ecosystem pollution with trace elements generates changes at the geochemistry cycle of these elements and in environmental quality. Soils have single characteristics when compared with another components of biosphere (air, water and biota), cause they introduce themselves not only as a drain towards contaminants, but also as natural buffer that control the transport of chemical elements and other substances for atmosphere, hydrosphere and biota. The main purpose of environmental monitoring program is to evaluate the levels of contaminants in the various compartments of the environment: natural or anthropogenic, and to assess the contribution of a potential contaminant source on the environment. Elemental Composition for the collected samples was determined by inductively coupled plasma mass spectroscopy. The main objective of this work was to evaluate the map baseline of concentration of interest trace elements in environmental samples of water, sediment and soil from Environmental Monitoring Program of Instituto de Radioprotecao e Dosimetria (IRD). The samples were analyzed using an inductively coupled plasma mass spectrometer (ICP-MS) at IRD. >From the knowledge of trace elements concentrations, could be evaluated the environmental quality parameters at the studied ecosystems. The data allowed evaluating some relevant aspects of the study of trace elements in soil and aquatic systems, with emphasis at the distribution, concentration and identification of main anthropic sources of contamination at environment. (author)

  7. Compartmented pyruvate in perfused working heart

    International Nuclear Information System (INIS)

    Buenger, R.

    1985-01-01

    Pyruvate compartmentation and lactate dehydrogenase (LDH) were studied in isolated perfused working guinea pig hearts. The mean intracellular pyruvate (Pyr) contents increased with perfusate Pyr (0-2 mM) but varied only slightly with glucose (0-10 mM) and additional insulin (0.04-5 U/l), respectively. With 5-10 mM glucose plus 5 U/l insulin, but not with Pyr or lactate (Lac) as substrates, a near equilibrium between the LDH and the glycerol-3-phosphate dehydrogenase seemed to exist. Evidence for an inhibitory effect of Pyr on the activity of the LDH system of the perfused hearts was not obtained. With [U- 14 C]glucose as sole substrate, the specific activity of coronary venous Lac was near half that of precursor glucose. 14 CO 2 production was thus in quantitative agreement with rates of pyruvate oxidation that were determined as glucose uptake minus (Pyr + Lac) release. In contrast, with 0.2 mM [1- 14 C]Pyr plus 5 mM glucose, the ratio of 14 CO 2 production to specific activity of Lac overestimated Pyr oxidation judged from myocardial substrate balances and O 2 uptake, respectively; here, at least three pools of [ 14 C]HCO-3 and [ 14 C]lac, respectively, were kinetically demonstrable during washout of trace amounts of 14 C-labeled Pyr. Evidently, the specific activity of Lac was equivalent to that of mitochondrial oxidized Pyr provided [ 14 C]glucose was the sole or major precursor of cellular pyruvate. However, exogenously applied [1- 14 C]Pyr of high specific activity seemed to induce intracellular formation of both a highly and lowly labeled Pyr; the latter Pyr compartment did not seem in ready equilibrium with the cell physiologically prevailing highly labeled Pyr pool

  8. Developments in uranium enrichment

    International Nuclear Information System (INIS)

    Mohrhauer, H.

    1995-01-01

    The enrichment services market is still characterized by overcapacities. While consumption worldwide will rise by some 15% to 39,000 t SWU/a over the next ten years, capacities amount to nearly 50,000 t SWU/a. The price for enrichment services probably has reached its all time low. Prices below U.S. $ 100/kg SWU are not likely to cover costs even of the economically most advanced enrichment processes. Urenco has prepared for the difficult enrichment business in the years to come by streamlining and cost cutting measures. The company intends to hold and increase its share of more than 10% in the world market. The uranium enrichment plant of Gronau will be expanded further. Expansion beyond 1000 t is subject to another permit being granted under the Atomic Energy Act, an application for which was filed in December 1994. Centrifuge technology is the superior enrichment technology, i.e., there is still considerable potential for further development. Construction of enrichment plants employing the centrifuge technology in the United States and in France is being pursued in various phases, from feasibility studies to licensing procedures. Before these plants could be implemented, however, considerable problems of organization would have to be solved, and the market would have to change greatly, respectively. The laser process, at the present time, does not seem to be able to develop into a major industrial competitor. (orig.) [de

  9. TRIGA low enrichment fuel

    International Nuclear Information System (INIS)

    Gietzen, A.

    1993-01-01

    Sixty TRIGA reactors have been sold and the earliest of these are now passing twenty years of operation. All of these reactors use the uranium zirconium hydride fuel (UZrH) which provides certain unique advantages arising out of its large prompt negative temperature coefficient, very low fission product release, and high temperature capability. Eleven of these Sixty reactors are conversions from plate fuel to TRIGA fuel which were made as a result of these advantages. With only a few exceptions, TRIGA reactors have always used low-enriched uranium (LEU) fuel with an enrichment of 19.9%. The exceptions have either been converted from the standard low-enriched fuel to the 70% enriched FLIP fuel in order to achieve extended lifetime, or are higher powered reactors which were designed for long life using 93%-enriched uranium during the time when the use and export of highly enriched uranium (HEU) was not restricted. The advent of international policies focusing attention on nonproliferation and safeguards made the HEU fuels obsolete. General Atomic immediately undertook a development effort (nearly two years ago) in order to be in a position to comply with these policies for all future export sales and also to provide a low-enriched alternative to fully enriched plate-type fuels. This important work was subsequently partially supported by the U.S. Department of Energy. The laboratory and production tests have shown that higher uranium densities can be achieved to compensate for reducing the enrichment to 20%, and that the fuels maintain the characteristics of the very thoroughly proven standard TRIGA fuels. In May of 1978, General Atomic announced that these fuels were available for TRIGA reactors and for plate-type reactors with power levels up to 15 MW with General Atomic's standard commercial warranty

  10. TRIGA low enrichment fuel

    International Nuclear Information System (INIS)

    Gietzen, A.

    1993-01-01

    Sixty TRIGA reactors have been sold and the earliest of these are now passing twenty years of operation. All of these reactors use the uranium-zirconium hydride fuel (UZrH) which provides certain unique advantages arising out of its large prompt negative temperature coefficient, very low fission product release, and high temperature capability. Eleven of these Sixty reactors are conversions from plate fuel to TRIGA fuel which were made as a result of these advantages. With only a few exceptions, TRIGA reactors have always used low-enriched-uranium (LEU) fuel with an enrichment of 19.9%. The exceptions have either been converted from the standard low-enriched fuel to the 70% enriched FLIP fuel in order to achieve extended lifetime, or are higher powered reactors which were designed for long life using 93%-enriched uranium during the time when the use and export of highly enriched uranium (HEU) was not restricted. The advent of international policies focusing attention on nonproliferation and safeguards made the HEU fuels obsolete. General Atomic immediately undertook a development effort (nearly two years ago) in order to be in a position to comply with these policies for all future export sales and also to provide a low-enriched alternative to fully enriched plate-type fuels. This important work was subsequently partially supported by the U.S. Department of Energy. The laboratory and production tests have shown that higher uranium densities can be achieved to compensate for reducing the enrichment to 20%, and that the fuels maintain the characteristics of the very thoroughly proven standard TRIGA fuels. In May of 1978, General Atomic announced that these fuels were available for TRIGA reactors and for plate-type reactors with power levels up to 15 MW with GA's standard commercial warranty

  11. Molecular Characterization of the Bacterial Communities in the Different Compartments of a Full-Scale Reverse-Osmosis Water Purification Plant

    NARCIS (Netherlands)

    Bereschenko, L.A.; Heilig, G.H.J.; Nederlof, M.M.; Loosdrecht, M.C.M. van; Stams, A.J.M.; Euverink, G.J.W.

    2008-01-01

    The origin, structure, and composition of biofilms in various compartments of an industrial full-scale reverse-osmosis (RO) membrane water purification plant were analyzed by molecular biological methods. Samples were taken when the RO installation suffered from a substantial pressure drop and

  12. Molecular characterization of the bacterial communities in the different compartments of a full-scale reverse-osmosis water purification plant

    NARCIS (Netherlands)

    Bereschenko, L.A.; Heilig, G.H.J.; Nederlof, M.M.; Loosdracht, van M.C.M.; Stams, A.J.M.; Euverink, G.J.W.

    2008-01-01

    The origin, structure, and composition of biofilms in various compartments of an industrial full-scale reverse-osmosis (RO) membrane water purification plant were analyzed by molecular biological methods. Samples were taken when the RO installation suffered from a substantial pressure drop and

  13. Nonlinear Effects in Osmotic Volume Flows of Electrolyte Solutions through Double-Membrane System

    NARCIS (Netherlands)

    Slezak, A.; Jasik-Slezak, J.; Grzegorczyn, S.; Slezak-Prochazka, I.

    The results of experimental study of volume osmotic flows in a double-membrane system are presented in this article. The double-membrane system consists of two membranes (M-u, M-d) oriented in horizontal planes and three identical compartments (u, m, d), containing unstirred binary or ternary ionic

  14. Hydrogen Peroxide Probes Directed to Different Cellular Compartments

    Science.gov (United States)

    Malinouski, Mikalai; Zhou, You; Belousov, Vsevolod V.; Hatfield, Dolph L.; Gladyshev, Vadim N.

    2011-01-01

    Background Controlled generation and removal of hydrogen peroxide play important roles in cellular redox homeostasis and signaling. We used a hydrogen peroxide biosensor HyPer, targeted to different compartments, to examine these processes in mammalian cells. Principal Findings Reversible responses were observed to various redox perturbations and signaling events. HyPer expressed in HEK 293 cells was found to sense low micromolar levels of hydrogen peroxide. When targeted to various cellular compartments, HyPer occurred in the reduced state in the nucleus, cytosol, peroxisomes, mitochondrial intermembrane space and mitochondrial matrix, but low levels of the oxidized form of the biosensor were also observed in each of these compartments, consistent with a low peroxide tone in mammalian cells. In contrast, HyPer was mostly oxidized in the endoplasmic reticulum. Using this system, we characterized control of hydrogen peroxide in various cell systems, such as cells deficient in thioredoxin reductase, sulfhydryl oxidases or subjected to selenium deficiency. Generation of hydrogen peroxide could also be monitored in various compartments following signaling events. Conclusions We found that HyPer can be used as a valuable tool to monitor hydrogen peroxide generated in different cellular compartments. The data also show that hydrogen peroxide generated in one compartment could translocate to other compartments. Our data provide information on compartmentalization, dynamics and homeostatic control of hydrogen peroxide in mammalian cells. PMID:21283738

  15. Hydrogen peroxide probes directed to different cellular compartments.

    Directory of Open Access Journals (Sweden)

    Mikalai Malinouski

    2011-01-01

    Full Text Available Controlled generation and removal of hydrogen peroxide play important roles in cellular redox homeostasis and signaling. We used a hydrogen peroxide biosensor HyPer, targeted to different compartments, to examine these processes in mammalian cells.Reversible responses were observed to various redox perturbations and signaling events. HyPer expressed in HEK 293 cells was found to sense low micromolar levels of hydrogen peroxide. When targeted to various cellular compartments, HyPer occurred in the reduced state in the nucleus, cytosol, peroxisomes, mitochondrial intermembrane space and mitochondrial matrix, but low levels of the oxidized form of the biosensor were also observed in each of these compartments, consistent with a low peroxide tone in mammalian cells. In contrast, HyPer was mostly oxidized in the endoplasmic reticulum. Using this system, we characterized control of hydrogen peroxide in various cell systems, such as cells deficient in thioredoxin reductase, sulfhydryl oxidases or subjected to selenium deficiency. Generation of hydrogen peroxide could also be monitored in various compartments following signaling events.We found that HyPer can be used as a valuable tool to monitor hydrogen peroxide generated in different cellular compartments. The data also show that hydrogen peroxide generated in one compartment could translocate to other compartments. Our data provide information on compartmentalization, dynamics and homeostatic control of hydrogen peroxide in mammalian cells.

  16. Lower limb compartment syndrome following laparoscopic colorectal surgery: a review.

    Science.gov (United States)

    Rao, M M; Jayne, D

    2011-05-01

      In spite of recent advances in technology and technique, laparoscopic colorectal surgery is associated with increased operating times when compared with open surgery. This increases the risk of acute lower limb compartment syndrome. The aim of this review was to gain a better understanding of postoperative lower limb compartment syndrome following laparoscopic colorectal surgery and to suggest strategies to avoid its occurrence. A MEDLINE search was performed using the keywords 'compartment syndrome', 'laparoscopic surgery' and 'Lloyd-Davies position' between 1970 and 2008. All relevant articles were retrieved and reviewed. A total of 54 articles were retrieved. Of the 30 articles in English, five were reviews, six were original articles and 19 were case reports, of which only one was following laparoscopic colorectal surgery. The remaining 24 were non-English articles. Of these, two were reviews and 22 were case reports, of which only one was following laparoscopic colorectal surgery. The incidence of acute compartment syndrome following laparoscopic colorectal surgery is unknown. The following are believed to be risk factors for acute lower limb compartment syndrome: the Lloyd-Davies operating position with exaggerated Trendelenburg tilt, prolonged operative times and improper patient positioning. Simple strategies are suggested to reduce its occurrence. Simple preventative measures have been identified which may help to reduce the incidence of acute lower limb compartment syndrome. However, if suspected, timely surgical intervention with four-compartment fasciotomy remains the standard of care. © 2011 The Authors. Colorectal Disease © 2011 The Association of Coloproctology of Great Britain and Ireland.

  17. Stochastic Turing Patterns: Analysis of Compartment-Based Approaches

    KAUST Repository

    Cao, Yang; Erban, Radek

    2014-01-01

    © 2014, Society for Mathematical Biology. Turing patterns can be observed in reaction-diffusion systems where chemical species have different diffusion constants. In recent years, several studies investigated the effects of noise on Turing patterns and showed that the parameter regimes, for which stochastic Turing patterns are observed, can be larger than the parameter regimes predicted by deterministic models, which are written in terms of partial differential equations (PDEs) for species concentrations. A common stochastic reaction-diffusion approach is written in terms of compartment-based (lattice-based) models, where the domain of interest is divided into artificial compartments and the number of molecules in each compartment is simulated. In this paper, the dependence of stochastic Turing patterns on the compartment size is investigated. It has previously been shown (for relatively simpler systems) that a modeler should not choose compartment sizes which are too small or too large, and that the optimal compartment size depends on the diffusion constant. Taking these results into account, we propose and study a compartment-based model of Turing patterns where each chemical species is described using a different set of compartments. It is shown that the parameter regions where spatial patterns form are different from the regions obtained by classical deterministic PDE-based models, but they are also different from the results obtained for the stochastic reaction-diffusion models which use a single set of compartments for all chemical species. In particular, it is argued that some previously reported results on the effect of noise on Turing patterns in biological systems need to be reinterpreted.

  18. Characteristics of patients with chronic exertional compartment syndrome.

    Science.gov (United States)

    Davis, Daniel E; Raikin, Steven; Garras, David N; Vitanzo, Peter; Labrador, Hallie; Espandar, Ramin

    2013-10-01

    Chronic exertional compartment syndrome (CECS) is a condition that causes reversible ischemia and lower extremity pain during exercise. To date there are few large studies examining the characteristics of patients with CECS. This study aimed to present these characteristics by examining the largest published series of patients with a confirmed diagnosis of the disorder. An IRB-approved, retrospective review was undertaken of patients with a suspected diagnosis of CECS undergoing pre- and postexercise compartment pressure testing between 2000 and 2012. Patients were evaluated for gender, age, duration of symptoms, pain level, specific compartments involved, compartment pressure measurements, and participation and type of athletics. Two-hundred twenty-six patients (393 legs) underwent compartment pressure testing. A diagnosis of CECS was made in 153 (67.7%) patients and 250 (63.6%) legs with elevated compartment measurements; average age of the patients was 24 years (range, 13-69 years). Female patients accounted for 92 (60.1%) of those with elevated pressures. Anterior and lateral compartment pressures were elevated most frequently, with 200 (42.5%) and 167 (35.5%) compartments, respectively. One hundred forty-one (92.2%) patients reported participation in sports, with running being the most common individual sport and soccer being the most common team sport. Duration of pain prior to diagnosis averaged 28 months. Although there is ample literature pertaining to the diagnostic criteria and treatment algorithm of the condition, few papers have described the type of patient most likely to develop CECS. This is the largest study to date to evaluate the type of patient likely to present with chronic exertional compartment syndrome. Level III, retrospective review.

  19. Stochastic Turing Patterns: Analysis of Compartment-Based Approaches

    KAUST Repository

    Cao, Yang

    2014-11-25

    © 2014, Society for Mathematical Biology. Turing patterns can be observed in reaction-diffusion systems where chemical species have different diffusion constants. In recent years, several studies investigated the effects of noise on Turing patterns and showed that the parameter regimes, for which stochastic Turing patterns are observed, can be larger than the parameter regimes predicted by deterministic models, which are written in terms of partial differential equations (PDEs) for species concentrations. A common stochastic reaction-diffusion approach is written in terms of compartment-based (lattice-based) models, where the domain of interest is divided into artificial compartments and the number of molecules in each compartment is simulated. In this paper, the dependence of stochastic Turing patterns on the compartment size is investigated. It has previously been shown (for relatively simpler systems) that a modeler should not choose compartment sizes which are too small or too large, and that the optimal compartment size depends on the diffusion constant. Taking these results into account, we propose and study a compartment-based model of Turing patterns where each chemical species is described using a different set of compartments. It is shown that the parameter regions where spatial patterns form are different from the regions obtained by classical deterministic PDE-based models, but they are also different from the results obtained for the stochastic reaction-diffusion models which use a single set of compartments for all chemical species. In particular, it is argued that some previously reported results on the effect of noise on Turing patterns in biological systems need to be reinterpreted.

  20. 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....

  1. Leishmania hijacking of the macrophage intracellular compartments.

    Science.gov (United States)

    Liévin-Le Moal, Vanessa; Loiseau, Philippe M

    2016-02-01

    Leishmania spp., transmitted to humans by the bite of the sandfly vector, are responsible for the three major forms of leishmaniasis, cutaneous, diffuse mucocutaneous and visceral. Leishmania spp. interact with membrane receptors of neutrophils and macrophages. In macrophages, the parasite is internalized within a parasitophorous vacuole and engages in a particular intracellular lifestyle in which the flagellated, motile Leishmania promastigote metacyclic form differentiates into non-motile, metacyclic amastigote form. This phenomenon is induced by Leishmania-triggered events leading to the fusion of the parasitophorous vacuole with vesicular members of the host cell endocytic pathway including recycling endosomes, late endosomes and the endoplasmic reticulum. Maturation of the parasitophorous vacuole leads to the intracellular proliferation of the Leishmania amastigote forms by acquisition of host cell nutrients while escaping host defense responses. © 2015 FEBS.

  2. 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

  3. Involvement of glycosphingolipid-enriched lipid rafts in inflammatory responses.

    Science.gov (United States)

    Iwabuchi, Kazuhisa

    2015-01-01

    Glycosphingolipids (GSLs) are membrane components consisting of hydrophobic ceramide and hydrophilic sugar moieties. GSLs cluster with cholesterol in cell membranes to form GSL-enriched lipid rafts. Biochemical analyses have demonstrated that GSL-enriched lipid rafts contain several kinds of transducer molecules, including Src family kinases. Among the GSLs, lactosylceramide (LacCer, CDw17) can bind to various microorganisms, is highly expressed on the plasma membranes of human phagocytes, and forms lipid rafts containing the Src family tyrosine kinase Lyn. LacCer-enriched lipid rafts mediate immunological and inflammatory reactions, including superoxide generation, chemotaxis, and non-opsonic phagocytosis. Therefore, LacCer-enriched membrane microdomains are thought to function as pattern recognition receptors (PRRs), which recognize pathogen-associated molecular patterns (PAMPs) expressed on microorganisms. LacCer also serves as a signal transduction molecule for functions mediated by CD11b/CD18-integrin (αM/β2-integrin, CR3, Mac-1), as well as being associated with several key cellular processes. LacCer recruits PCKα/ε and phospholipase A2 to stimulate PECAM-1 expression in human monocytes and their adhesion to endothelial cells, as well as regulating β1-integrin clustering and endocytosis on cell surfaces. This review describes the organizational and inflammation-related functions of LacCer-enriched lipid rafts.

  4. Protein-centric N-glycoproteomics analysis of membrane and plasma membrane proteins.

    Science.gov (United States)

    Sun, Bingyun; Hood, Leroy

    2014-06-06

    The advent of proteomics technology has transformed our understanding of biological membranes. The challenges for studying membrane proteins have inspired the development of many analytical and bioanalytical tools, and the techniques of glycoproteomics have emerged as an effective means to enrich and characterize membrane and plasma-membrane proteomes. This Review summarizes the development of various glycoproteomics techniques to overcome the hurdles formed by the unique structures and behaviors of membrane proteins with a focus on N-glycoproteomics. Example contributions of N-glycoproteomics to the understanding of membrane biology are provided, and the areas that require future technical breakthroughs are discussed.

  5. Membrane microdomains, rafts, and detergent-resistant membranes in plants and fungi.

    Science.gov (United States)

    Malinsky, Jan; Opekarová, Miroslava; Grossmann, Guido; Tanner, Widmar

    2013-01-01

    The existence of specialized microdomains in plasma membranes, postulated for almost 25 years, has been popularized by the concept of lipid or membrane rafts. The idea that detergent-resistant membranes are equivalent to lipid rafts, which was generally abandoned after a decade of vigorous data accumulation, contributed to intense discussions about the validity of the raft concept. The existence of membrane microdomains, meanwhile, has been verified by unequivocal independent evidence. This review summarizes the current state of research in plants and fungi with respect to common aspects of both kingdoms. In these organisms, principally immobile microdomains large enough for microscopic detection have been visualized. These microdomains are found in the context of cell-cell interactions (plant symbionts and pathogens), membrane transport, stress, and polarized growth, and the data corroborate at least three mechanisms of formation. As documented in this review, modern methods of visualization of lateral membrane compartments are also able to uncover the functional relevance of membrane microdomains.

  6. Numerical calculation on a two-step subdiffusion behavior of lateral protein movement in plasma membranes

    Science.gov (United States)

    Sumi, Tomonari; Okumoto, Atsushi; Goto, Hitoshi; Sekino, Hideo

    2017-10-01

    A two-step subdiffusion behavior of lateral movement of transmembrane proteins in plasma membranes has been observed by using single-molecule experiments. A nested double-compartment model where large compartments are divided into several smaller ones has been proposed in order to explain this observation. These compartments are considered to be delimited by membrane-skeleton "fences" and membrane-protein "pickets" bound to the fences. We perform numerical simulations of a master equation using a simple two-dimensional lattice model to investigate the heterogeneous diffusion dynamics behavior of transmembrane proteins within plasma membranes. We show that the experimentally observed two-step subdiffusion process can be described using fence and picket models combined with decreased local diffusivity of transmembrane proteins in the vicinity of the pickets. This allows us to explain the two-step subdiffusion behavior without explicitly introducing nested double compartments.

  7. EFFECT OF PHOSPHOLIPASE-A2 ON SYK-MEDIATED PHOSPHORYLATION OF HUMAN ERYTHROCYTE MEMBRANE

    Directory of Open Access Journals (Sweden)

    Lucian Bordin

    2006-08-01

    , lacking in p36 isoform, are responsible of the lower ability of kinase of catalysing band 3 Tyr-phosphorylation, probably due either to steric bulk, or to particular sequestering of the holoenzyme into membrane compartment.

  8. Salt splitting using ceramic membranes

    Energy Technology Data Exchange (ETDEWEB)

    Kurath, D.E. [Pacific Northwest National Lab., Richland, WA (United States)

    1997-10-01

    Many radioactive aqueous wastes in the DOE complex have high concentrations of sodium that can negatively affect waste treatment and disposal operations. Sodium can decrease the durability of waste forms such as glass and is the primary contributor to large disposal volumes. Waste treatment processes such as cesium ion exchange, sludge washing, and calcination are made less efficient and more expensive because of the high sodium concentrations. Pacific Northwest National Laboratory (PNNL) and Ceramatec Inc. (Salt Lake City UT) are developing an electrochemical salt splitting process based on inorganic ceramic sodium (Na), super-ionic conductor (NaSICON) membranes that shows promise for mitigating the impact of sodium. In this process, the waste is added to the anode compartment, and an electrical potential is applied to the cell. This drives sodium ions through the membrane, but the membrane rejects most other cations (e.g., Sr{sup +2}, Cs{sup +}). The charge balance in the anode compartment is maintained by generating H{sup +} from the electrolysis of water. The charge balance in the cathode is maintained by generating OH{sup {minus}}, either from the electrolysis of water or from oxygen and water using an oxygen cathode. The normal gaseous products of the electrolysis of water are oxygen at the anode and hydrogen at the cathode. Potentially flammable gas mixtures can be prevented by providing adequate volumes of a sweep gas, using an alternative reductant or destruction of the hydrogen as it is generated. As H{sup +} is generated in the anode compartment, the pH drops. The process may be operated with either an alkaline (pH>12) or an acidic anolyte (pH <1). The benefits of salt splitting using ceramic membranes are (1) waste volume reduction and reduced chemical procurement costs by recycling of NaOH; and (2) direct reduction of sodium in process streams, which enhances subsequent operations such as cesium ion exchange, calcination, and vitrification.

  9. 14 CFR 25.365 - Pressurized compartment loads.

    Science.gov (United States)

    2010-01-01

    ... flight, and stress concentrations and fatigue effects must be accounted for. (c) If landings may be made... small compartment. The size Ho must be computed by the following formula: Ho=PAs where, Ho=Maximum...

  10. Turbofan Engine Core Compartment Vent Aerodynamic Configuration Development Methodology

    Science.gov (United States)

    Hebert, Leonard J.

    2006-01-01

    This paper presents an overview of the design methodology used in the development of the aerodynamic configuration of the nacelle core compartment vent for a typical Boeing commercial airplane together with design challenges for future design efforts. Core compartment vents exhaust engine subsystem flows from the space contained between the engine case and the nacelle of an airplane propulsion system. These subsystem flows typically consist of precooler, oil cooler, turbine case cooling, compartment cooling and nacelle leakage air. The design of core compartment vents is challenging due to stringent design requirements, mass flow sensitivity of the system to small changes in vent exit pressure ratio, and the need to maximize overall exhaust system performance at cruise conditions.

  11. Environmental fate and transport analysis with compartment modeling

    National Research Council Canada - National Science Library

    Little, Keith W

    2012-01-01

    .... Discussing various modeling issues in a single volume, this text provides an introduction to a specific numerical modeling technique called the compartment approach and offers a practical user's guide to the GEM...

  12. Chronic exertional compartment syndrome in the forearm of a rower

    African Journals Online (AJOL)

    ICP) measurement (Fig. 1). Testing of the flexor compart- ments revealed a raised resting pressure of 16 ... the following values suggestive of CECS in the lower limb: A pre- ... toxin decreases muscle mass and therefore causes a reduction of.

  13. Microbial investigations of deep geological compartments

    International Nuclear Information System (INIS)

    Barsotti, V.; Sergeant, C.; Vesvres, M.H.; Joulian, C.; Coulon, S.; Le Marrec, C.; Garrido, F.

    2010-01-01

    Document available in extended abstract form only. Deep sedimentary rocks are now considered to contain a significant part of the total bacterial population, but are microbiologically unexplored. The drilling down to the base of the Triassic (1980 meters deep) in the geological formations of the eastern Paris Basin performed by ANDRA (EST433) in 2008 provides us a good opportunity to explore the deep biosphere. We conditioned and sub-sampled on the coring site, in as aseptic conditions as possible, the nine cores: two in the Callovo-Oxfordian clay, two in the Dogger, five in the Triassic compartments. In addition to storage at atmospheric pressure, a portion of the five Triassic samples was placed in a 190 bars pressurized bars chamber to investigate the influence of the conservation pressure factor on the found microflora. In parallel, in order to evaluate a potential bacterial contamination of the core by the drilling fluids, samples of mud just before each sample drilling were taken and analysed. The microbial exploration we started can be divided in two parts: - A cultural approach in different culture media for six metabolic groups to try to find microbial cells still viable. This type of experiment is difficult because of the small proportion of cultivable species, especially in these extreme environmental samples. - A molecular approach by direct extraction of genomic DNA from the geological samples to explore a larger biodiversity. Here, the limits are the difficulties to extract DNA from these low biomass containing rocks. The five Triassic samples were partly crushed in powder and inoculated in the six culture media with four NaCl concentrations, because this type of rock is known as saline or hyper-saline, and incubated at three temperatures: 30 deg. C, 55 deg. C under agitation and 70 deg. C. First results will be presented. The direct extraction of DNA needs a complete method optimisation to adapt existent procedures (using commercial kit and classical

  14. Topology Optimization of Spacecraft Transfer Compartment

    Directory of Open Access Journals (Sweden)

    A. A. Borovikov

    2016-01-01

    Full Text Available IntroductionThe subject of this research is topology optimization of the adapter of a spacecraft transfer compartment. The finite element topology optimization [1] is widely used for simple structure elements [6, 7]. It is argued that using this method in conjunction with additive technology (3D - printing it is possible to create construction designs with the best weight characteristics. However, the paper shows that when applying this method to a complex construction design the optimization results are highly sensitive to optimization algorithm parameters. The goal of this research is to study parameters of the topology optimization algorithm and the influence of their variations on results.1.      Problem formulation   A commercial software Altair HyperWorks/OptiStruct (student’s license performed numerical calculations. The paper presents a detailed description of the finite element model.The main features of the proposed model are as follows:-          Simplicity with non-complicated geometry;-          Building a finite element model in terms of computing time minimization;-          Using the lumped mass elements to simulate the impacts of the conjugates on the adapter;-          A limit of material strength, decreased by an order of magnitude, to eliminate stress concentrators;-          The gravitational load applied corresponds to the loads for the Angara-A5 launcher [8]. 2.      Method of solutionA brief description of the SIMP-method realized in the Altair HyperWorks/OptiStruct software is given.3.      ResultsPerformed numerical calculations, and shown the influence of variations of algorithm parameters (DISCRETE, MATINIT, MINDIM, MAXDIM on construction design as well as the parameters SINGLE and SPLIT used to reveal restrictions on manufacturing.Shown that, depending on variations of parameters, an adapter construction strives to «truss» or «shell» type. Described

  15. The competitive enrichment market

    International Nuclear Information System (INIS)

    Parks, J.W.; Huffman, F.C.

    1984-01-01

    With the enactment of the ''Private Ownership of Special Nuclear Materials Act'' in 1964, the U.S. Government made provisions to enter into the uranium enrichment services business. Since nuclear power was in its infancy and the Government was promoting its growth as well as trying to help U.S. industry sell reactors overseas, the initial contracts (Requirements Contracts) for enrichment services placed most of the risks associated with the supplying of the services on the Government. Projections of nuclear power additions continued to grow and in 1972 the Atomic Energy Commission (AEC) stopped contracting under Requirements Contracts in order to study which mode of contracting best suited the commercial development of the industry. In mid-1973, the AEC introduced the Long-Term Fixed Commitment (LTFC) contract which shifted the risk to the customer. By mid-1974, AEC had contracts which completely used the enrichment capacity of its complex and refused to accept requests for additional contracts. This action further convinced European nations that they should continue to develop their own enrichment capacity and resulted in the EURODIF and URENCO projects. Before this time the U.S. supplied 100% of the world market for enriching services

  16. Enrichment: Dealing with overcapacity

    International Nuclear Information System (INIS)

    Peterson, C.H.

    1989-01-01

    Today's surplus of enrichment capacity will continue until at least the end of this century. This will challenge the ingenuity of the separative work unit (SWU) suppliers as they attempt to keep market share and remain profitable in a very competitive marketplace. The utilities will be faced with attractive choices, but making the best choice will require careful analysis and increased attention to market factors. Current demand projections will probably prove too high to the extent that more reactors are canceled or delayed. The DOE has the vast majority of the unused capacity, so it will feel the most immediate impact of this large surplus in productive capacity. The DOE has responded to these market challenges by planning another reorganization of its enriching operations. Without a major agreement among the governments affected by the current surplus in enrichment capacity, the future will see lower prices, more competitive terms, and the gradual substitution of centrifuge or laser enrichment for the gaseous diffusion plants. The competition that is forcing the gaseous diffusion prices down to marginal cost will provide the long-term price basis for the enrichment industry

  17. Drought Stress Results in a Compartment-Specific Restructuring of the Rice Root-Associated Microbiomes

    Directory of Open Access Journals (Sweden)

    Christian Santos-Medellín

    2017-07-01

    Full Text Available Plant roots support complex microbial communities that can influence plant growth, nutrition, and health. While extensive characterizations of the composition and spatial compartmentalization of these communities have been performed in different plant species, there is relatively little known about the impact of abiotic stresses on the root microbiota. Here, we have used rice as a model to explore the responses of root microbiomes to drought stress. Using four distinct genotypes, grown in soils from three different fields, we tracked the drought-induced changes in microbial composition in the rhizosphere (the soil immediately surrounding the root, the endosphere (the root interior, and unplanted soils. Drought significantly altered the overall bacterial and fungal compositions of all three communities, with the endosphere and rhizosphere compartments showing the greatest divergence from well-watered controls. The overall response of the bacterial microbiota to drought stress was taxonomically consistent across soils and cultivars and was primarily driven by an enrichment of multiple Actinobacteria and Chloroflexi, as well as a depletion of several Acidobacteria and Deltaproteobacteria. While there was some overlap in the changes observed in the rhizosphere and endosphere communities, several drought-responsive taxa were compartment specific, a pattern likely arising from preexisting compositional differences, as well as plant-mediated processes affecting individual compartments. These results reveal that drought stress, in addition to its well-characterized effects on plant physiology, also results in restructuring of root microbial communities and suggest the possibility that constituents of the altered plant microbiota might contribute to plant survival under extreme environmental conditions.

  18. The role of each compartment in a two-compartment vertical flow reactor for ferruginous mine water treatment.

    Science.gov (United States)

    Yim, G J; Cheong, Y W; Hong, J H; Hur, W

    2014-10-01

    A vertical flow reactor (VFR) has been suggested for remediation of ferruginous mine drainage that passes down through an accreting bed of ochre. However, a VFR has a limited operation time until the system begins to overflow. In this study, a mathematical model was developed as a part of the effort to explore the operation of a VFR, showing dynamic changes in the head differences, ochre depths, and Fe(II)/Fe(III) concentrations in the effluent flow. The analysis showed that VFR operation time extended from 148.5 days to 163 days in an equally divided and to 168.4 days in asymmetrically (0.72:0.28) divided two-compartment VFR, suggesting that an optimum compartment ratio exists that maximizes the VFR operation time. A constant head filtration in the first compartment maximized filtration efficiency and thus prolonged VFR longevity in the two-compartment VFR. Fe(II) oxidation and ochre formation should be balanced with the permeability of the ochre bed to maximize the VFR operation time and minimize the residual Fe(II) in the effluent. Accelerated Fe(II) oxidation affected the optimum ratio of the compartment area and reduced the residual Fe(II) in the effluent. The VFR operation time can be prolonged significantly from 764 days to 3620 days by increasing the rate of ochre formation, much more than by accelerating the Fe(II) oxidation. During the prolonged VFR operation, ochre formed largely in the first compartment, while overflowing mine water with reduced iron content was effectively filtered in the second compartment. These results not only provide a better understanding of VFR operation but also suggest the direction of evolution of two-compartment VFR toward a compact and highly efficient facility integrated with an aerated cascade and with automatic coagulant feeding. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Laser and gas centrifuge enrichment

    Energy Technology Data Exchange (ETDEWEB)

    Heinonen, Olli [Senior Fellow, Belfer Center for Science and International Affairs, Harvard Kennedy School, Cambridge, Massachusetts (United States)

    2014-05-09

    Principles of uranium isotope enrichment using various laser and gas centrifuge techniques are briefly discussed. Examples on production of high enriched uranium are given. Concerns regarding the possibility of using low end technologies to produce weapons grade uranium are explained. Based on current assessments commercial enrichment services are able to cover the global needs of enriched uranium in the foreseeable future.

  20. Oxygen enrichment incineration

    International Nuclear Information System (INIS)

    Kim, Jeong Guk; Yang, Hee Chul; Park, Geun Il; Kim, Joon Hyung

    2000-10-01

    Oxygen enriched combustion technology has recently been used in waste incineration. To apply the oxygen enrichment on alpha-bearing waste incineration, which is being developed, a state-of-an-art review has been performed. The use of oxygen or oxygen-enriched air instead of air in incineration would result in increase of combustion efficiency and capacity, and reduction of off-gas product. Especially, the off-gas could be reduced below a quarter, which might reduce off-gas treatment facilities, and also increase an efficiency of off-gas treatment. However, the use of oxygen might also lead to local overheating and high nitrogen oxides (NOx) formation. To overcome these problems, an application of low NOx oxy-fuel burner and recycling of a part of off-gas to combustion chamber have been suggested

  1. Oxygen enrichment incineration

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeong Guk; Yang, Hee Chul; Park, Geun Il; Kim, Joon Hyung

    2000-10-01

    Oxygen enriched combustion technology has recently been used in waste incineration. To apply the oxygen enrichment on alpha-bearing waste incineration, which is being developed, a state-of-an-art review has been performed. The use of oxygen or oxygen-enriched air instead of air in incineration would result in increase of combustion efficiency and capacity, and reduction of off-gas product. Especially, the off-gas could be reduced below a quarter, which might reduce off-gas treatment facilities, and also increase an efficiency of off-gas treatment. However, the use of oxygen might also lead to local overheating and high nitrogen oxides (NOx) formation. To overcome these problems, an application of low NOx oxy-fuel burner and recycling of a part of off-gas to combustion chamber have been suggested.

  2. Centrifuge enrichment program

    International Nuclear Information System (INIS)

    Astley, E.R.

    1976-01-01

    Exxon Nuclear has been active in privately funded research and development of centrifuge enrichment technology since 1972. In October of 1975, Exxon Nuclear submitted a proposal to design, construct, and operate a 3000-MT SWU/yr centrifuge enrichment plant, under the provisions of the proposed Nuclear Fuel Assurance Act of 1975. The U.S. Energy Research and Development Administration (ERDA) accepted the proposal as a basis for negotiation. It was proposed to build a 1000-MT SWU/yr demonstration increment to be operational in 1982; and after successful operation for about one year, expand the facilities into a 3000-MT SWU/yr plant. As part of the overall centrifuge enrichment plant, a dedicated centrifuge manufacturing plant would be constructed; sized to support the full 3000-MT SWU/yr plant. The selection of the centrifuge process by Exxon Nuclear was based on an extremely thorough evaluation of current and projected enrichment technology; results show that the technology is mature and the process will be cost effective. The substantial savings in energy (about 93%) from utilization of the centrifuge option rather than gaseous diffusion is a compelling argument. As part of this program, Exxon Nuclear has a large hardware R and D program, plus a prototype centrifuge manufacturing capability in Malta, New York. To provide a full-scale machine and limited cascade test capability, Exxon Nuclear is constructing a $4,000,000 Centrifuge Test Facility in Richland, Washington. This facility was to initiate operations in the Fall of 1976. Exxon Nuclear is convinced that the centrifuge enrichment process is the rational selection for emergence of a commercial enrichment industry

  3. US enrichment reduction studies

    International Nuclear Information System (INIS)

    1979-06-01

    A major national program, the Reduced Enrichment Research and Test Reactor (RERTR) Program, is currently under way in the U.S., centered at the Argonne National Laboratory (ANL), to reduce the potential of research and test reactor fuels for increasing the proliferation of nuclear explosive devices. The main objective of the program is to provide the technical means by which the uranium enrichment to be used in these reactors can be reduced to less than 20% without significant economic and performance penalties. The criteria, basis and goals of the program are consistent with the results of a number of case studies which have been performed as part of the program

  4. Advanced uranium enrichment processes

    International Nuclear Information System (INIS)

    Clerc, M.; Plurien, P.

    1986-01-01

    Three advanced Uranium enrichment processes are dealt with in the report: AVLIS (Atomic Vapour LASER Isotope Separation), MLIS (Molecular LASER Isotope Separation) and PSP (Plasma Separation Process). The description of the physical and technical features of the processes constitutes a major part of the report. If further presents comparisons with existing industrially used enrichment technologies, gives information on actual development programmes and budgets and ends with a chapter on perspectives and conclusions. An extensive bibliography of the relevant open literature is added to the different subjects discussed. The report was drawn up by the nuclear research Centre (CEA) Saclay on behalf of the Commission of the European Communities

  5. Uranium Conversion & Enrichment

    Energy Technology Data Exchange (ETDEWEB)

    Karpius, Peter Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-02-06

    The isotopes of uranium that are found in nature, and hence in ‘fresh’ Yellowcake’, are not in relative proportions that are suitable for power or weapons applications. The goal of conversion then is to transform the U3O8 yellowcake into UF6. Conversion and enrichment of uranium is usually required to obtain material with enough 235U to be usable as fuel in a reactor or weapon. The cost, size, and complexity of practical conversion and enrichment facilities aid in nonproliferation by design.

  6. An Enriching Community.

    Science.gov (United States)

    Holland, Nancy A.; Burroughs, Jean

    2001-01-01

    Successful school-community partnerships in Volusia (Florida) Public Schools are the results of marketing creatively, meeting community members' needs, and bringing the right people together. The 3-year old program now offers students of all ages an expanding list of enrichment classes on many subjects for a nominal fee. (MLH)

  7. Uranium enrichment techniques

    International Nuclear Information System (INIS)

    Hamdoun, N.A.

    2007-01-01

    This article includes an introduction about the isotopes of natural uranium, their existence and the difficulty of the separation between them. Then it goes to the details of a number of methods used to enrich uranium: Gaseous Diffusion method, Electromagnetic method, Jet method, Centrifugal method, Chemical method, Laser method and Plasma method.

  8. Requirements for enrichment tools

    NARCIS (Netherlands)

    Boer, A.; Winkels, R.; Trompper, M.

    2016-01-01

    This report gives a high level overview of requirements for Enrichment tools in the Openlaws.eu project. Openlaws.eu aims to initiate a platform and develop a vision for Big Open Legal Data (BOLD): an open framework for legislation, case law, and legal literature from across Europe.

  9. Enriching the Catalog

    Science.gov (United States)

    Tennant, Roy

    2004-01-01

    After decades of costly and time-consuming effort, nearly all libraries have completed the retrospective conversion of their card catalogs to electronic form. However, bibliographic systems still are really not much more than card catalogs on wheels. Enriched content that Amazon.com takes for granted--such as digitized tables of contents, cover…

  10. Availability of enrichment services

    International Nuclear Information System (INIS)

    Svenke, E.

    1977-01-01

    The report summarizes major uncertainties which are likely to influence future demands for uranium isotopic enrichment. Since for the next decade the development of nuclear power will be largely concerned with the increment in demand the timely need for enrichment capacity will be particularly sensitive to assumptions about growth rates. Existing worldwide capacity together with capacities under construction will be sufficient well into the 1980's. However, long decision and construction leadtime, uncertainty as to future demand as well as other factors, specifically high capital need, all of which entail financial risks, create hindrances to a timely development of increment. The adequacy of current technology is well demonstrated in plant operation and new technology is under way. Technology is, however, not freely available on a purely commercial basis. Commercial willingness, which anticipates a limited degree of financial risk, is requesting both long term back-up from the utilities that would parallel their firm decisions on the acquisition of nuclear power units, and a protective government umbrella. This situation depends on the symbiotic relationship that exists between the nuclear power generating organizations, the enrichment undertakings and the governments involved. The report accordingly stresses the need for a more cooperative approach and this, moreover, at the multinational level. There is otherwise a risk that proper resources and financing means will not be allocated to the enrichment sector. Export limitations that request the highest degree of industrial processing of nuclear fuel, i.e. the compulsory enrichment of natural uranium, do not serve the interests of overall industrial efficiency

  11. Measurement of compartment elasticity using pressure related ultrasound: a method to identify patients with potential compartment syndrome.

    Science.gov (United States)

    Sellei, R M; Hingmann, S J; Kobbe, P; Weber, C; Grice, J E; Zimmerman, F; Jeromin, S; Gansslen, A; Hildebrand, F; Pape, H C

    2015-01-01

    PURPOSE OF THE STUDY Decision-making in treatment of an acute compartment syndrome is based on clinical assessment, supported by invasive monitoring. Thus, evolving compartment syndrome may require repeated pressure measurements. In suspected cases of potential compartment syndromes clinical assessment alone seems to be unreliable. The objective of this study was to investigate the feasibility of a non-invasive application estimating whole compartmental elasticity by ultrasound, which may improve accuracy of diagnostics. MATERIAL AND METHODS In an in-vitro model, using an artificial container simulating dimensions of the human anterior tibial compartment, intracompartmental pressures (p) were raised subsequently up to 80 mm Hg by infusion of saline solution. The compartmental depth (mm) in the cross-section view was measured before and after manual probe compression (100 mm Hg) upon the surface resulting in a linear compartmental displacement (Δd). This was repeated at rising compartmental pressures. The resulting displacements were related to the corresponding intra-compartmental pressures simulated in our model. A hypothesized relationship between pressures related compartmental displacement and the elasticity at elevated compartment pressures was investigated. RESULTS With rising compartmental pressures, a non-linear, reciprocal proportional relation between the displacement (mm) and the intra-compartmental pressure (mm Hg) occurred. The Pearson's coefficient showed a high correlation (r2 = -0.960). The intraobserver reliability value kappa resulted in a statistically high reliability (κ = 0.840). The inter-observer value indicated a fair reliability (κ = 0.640). CONCLUSIONS Our model reveals that a strong correlation between compartmental strain displacements assessed by ultrasound and the intra-compartmental pressure changes occurs. Further studies are required to prove whether this assessment is transferable to human muscle tissue. Determining the complete

  12. 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.

  13. Increased pressure within the abdominal compartment: intra-abdominal hypertension and the abdominal compartment syndrome.

    Science.gov (United States)

    Roberts, Derek J; Ball, Chad G; Kirkpatrick, Andrew W

    2016-04-01

    This article reviews recent developments related to intra-abdominal hypertension (IAH)/abdominal compartment syndrome (ACS) and clinical practice guidelines published in 2013. IAH/ACS often develops because of the acute intestinal distress syndrome. Although the incidence of postinjury ACS is decreasing, IAH remains common and associated with significant morbidity and mortality among critically ill/injured patients. Many risk factors for IAH include those findings suggested to be indications for use of damage control surgery in trauma patients. Medical management strategies for IAH/ACS include sedation/analgesia, neuromuscular blocking and prokinetic agents, enteral decompression tubes, interventions that decrease fluid balance, and percutaneous catheter drainage. IAH/ACS may be prevented in patients undergoing laparotomy by leaving the abdomen open where appropriate. If ACS cannot be prevented with medical or surgical management strategies or treated with percutaneous catheter drainage, guidelines recommend urgent decompressive laparotomy. Use of negative pressure peritoneal therapy for temporary closure of the open abdomen may improve the systemic inflammatory response and patient-important outcomes. In the last 15 years, investigators have better clarified the pathogenesis, epidemiology, diagnosis, and appropriate prevention of IAH/ACS. Subsequent study should be aimed at understanding which treatments effectively lower intra-abdominal pressure and whether these treatments ultimately affect patient-important outcomes.

  14. Promotion of uranium enrichment business

    International Nuclear Information System (INIS)

    Kurushima, Morihiro

    1981-01-01

    The Committee on Nuclear Power has studied on the basic nuclear power policy, establishing its five subcommittees, entrusted by the Ministry of Nternational Trade and Industry. The results of examination by the subcommittee on uranium enrichment business are given along with a report in this connection by the Committee. In order to establish the nuclear fuel cycle, the aspect of uranium enrichment is essential. The uranium enrichment by centrifugal process has proceeded steadily in Power Reactor and Nuclear Fuel Development Corporation. The following matters are described: the need for domestic uranium enrichment, the outlook for overseas enrichment services and the schedule for establishing domestic enrichment business, the current state of technology development, the position of the prototype enrichment plant, the course to be taken to establish enrichment business the main organization operating the prototype and commercial plants, the system of supplying centrifuges, the domestic conversion of natural uranium the subsidies for uranium enrichment business. (J.P.N.)

  15. United States uranium enrichment policies

    International Nuclear Information System (INIS)

    Roberts, R.W.

    1977-01-01

    ERDA's uranium enrichment program policies governing the manner in which ERDA's enrichment complex is being operated and expanded to meet customer requirements for separative work, research and development activities directed at providing technology alternatives for future enrichment capacity, and establishing the framework for additional domestic uranium enrichment capacity to meet the domestic and foreign nuclear industry's growing demand for enrichment services are considered. The ERDA enrichment complex consists of three gaseous diffusion plants located in Oak Ridge, Tennessee; Paducah, Kentucky; and Portsmouth, Ohio. Today, these plants provide uranium enrichment services for commercial nuclear power generation. These enrichment services are provided under contracts between the Government and the utility customers. ERDA's program involves a major pilot plant cascade, and pursues an advanced isotope separation technique for the late 1980's. That the United States must develop additional domestic uranium enrichment capacity is discussed

  16. [Study on essential oil separation from Forsythia suspensa oil-bearing water body based on vapor permeation membrane separation technology].

    Science.gov (United States)

    Zhang, Qian; Zhu, Hua-Xu; Tang, Zhi-Shu; Pan, Yong-Lan; Li, Bo; Fu, Ting-Ming; Yao, Wei-Wei; Liu, Hong-Bo; Pan, Lin-Mei

    2018-04-01

    To investigate the feasibility of vapor permeation membrane technology in separating essential oil from oil-water extract by taking the Forsythia suspensa as an example. The polydimethylsiloxane/polyvinylidene fluoride (PDMS/PVDF) composite flat membrane and a polyvinylidene fluoride (PVDF) flat membrane was collected as the membrane material respectively. Two kinds of membrane osmotic liquids were collected by self-made vapor permeation device. The yield of essential oil separated and enriched from two kinds of membrane materials was calculated, and the microscopic changes of membrane materials were analyzed and compared. Meanwhile, gas chromatography-mass spectrometry (GC-MS) was used to compare and analyze the differences in chemical compositions of essential oil between traditional steam distillation, PVDF membrane enriched method and PDMS/PVDF membrane enriched method. The results showed that the yield of essential oil enriched by PVDF membrane was significantly higher than that of PDMS/PVDF membrane, and the GC-MS spectrum showed that the content of main compositions was higher than that of PDMS/PVDF membrane; The GC-MS spectra showed that the components of essential oil enriched by PVDF membrane were basically the same as those obtained by traditional steam distillation. The above results showed that vapor permeation membrane separation technology shall be feasible for the separation of Forsythia essential oil-bearing water body, and PVDF membrane was more suitable for separation and enrichment of Forsythia essential oil than PDMS/PVDF membrane. Copyright© by the Chinese Pharmaceutical Association.

  17. Dynamics of HIV-containing compartments in macrophages reveal sequestration of virions and transient surface connections.

    Directory of Open Access Journals (Sweden)

    Raphaël Gaudin

    Full Text Available During HIV pathogenesis, infected macrophages behave as "viral reservoirs" that accumulate and retain virions within dedicated internal Virus-Containing Compartments (VCCs. The nature of VCCs remains ill characterized and controversial. Using wild-type HIV-1 and a replication-competent HIV-1 carrying GFP internal to the Gag precursor, we analyzed the biogenesis and evolution of VCCs in primary human macrophages. VCCs appear roughly 14 hours after viral protein synthesis is detected, initially contain few motile viral particles, and then mature to fill up with virions that become packed and immobile. The amount of intracellular Gag, the proportion of dense VCCs, and the density of viral particles in their lumen increased with time post-infection. In contrast, the secretion of virions, their infectivity and their transmission to T cells decreased overtime, suggesting that HIV-infected macrophages tend to pack and retain newly formed virions into dense compartments. A minor proportion of VCCs remains connected to the plasma membrane overtime. Surprisingly, live cell imaging combined with correlative light and electron microscopy revealed that such connections can be transient, highlighting their dynamic nature. Together, our results shed light on the late phases of the HIV-1 cycle and reveal some of its macrophage specific features.

  18. Exercise Induced Rhabdomyolysis with Compartment Syndrome and Renal Failure

    Directory of Open Access Journals (Sweden)

    Mary Colleen Bhalla

    2014-01-01

    Full Text Available Exertional rhabdomyolysis is sequela that is occasionally seen after strenuous exercise. The progression to compartment syndrome or renal failure is a rare complication that requires prompt recognition and treatment to prevent morbidity (Giannoglou et al. 2007. We present a case of a 22-year-old college football player who presented to the emergency department (ED after a typical leg workout as part of his weight conditioning. He was found to have rhabdomyolysis with evidence of renal insufficiency. His condition progressed to bilateral compartment syndrome and renal failure requiring dialysis. After bilateral fasciotomies were performed he had resolution of his compartment syndrome. He continued to be dialysis dependent and had no return of his renal function at discharge 12 days after admission.

  19. Biogenesis of plasma membrane cholesterol

    International Nuclear Information System (INIS)

    Lange, Y.

    1986-01-01

    A striking feature of the molecular organization of eukaryotic cells is the singular enrichment of their plasma membranes in sterols. The authors studies are directed at elucidating the mechanisms underlying this inhomogeneous disposition. Cholesterol oxidase catalyzes the oxidation of plasma membrane cholesterol in intact cells, leaving intracellular cholesterol pools untouched. With this technique, the plasma membrane was shown to contain 95% of the unesterified cholesterol of cultured human fibroblasts. Cholesterol synthesized from [ 3 H] acetate moved to the plasma membrane with a half-time of 1 h at 37 0 C. They used equilibrium gradient centrifugation of homogenates of biosynthetically labeled, cholesterol oxidase treated cells to examine the distribution of newly synthesized sterols among intracellular pools. Surprisingly, lanosterol, a major precursor of cholesterol, and intracellular cholesterol both peaked at much lower buoyant density than did 3-hydroxy-3-methylglutaryl-CoA reductase. This suggests that cholesterol biosynthesis is not taken to completion in the endoplasmic reticulum. The cholesterol in the buoyant fraction eventually moved to the plasma membrane. Digitonin treatment increased the density of the newly synthesized cholesterol fractions, indicating that nascent cholesterol in transit is associated with cholesterol-rich membranes. The authors are testing the hypothesis that the pathway of cholesterol biosynthesis is spatially organized in various intracellular membranes such that the sequence of biosynthetic steps both concentrates the sterol and conveys it to the plasma membrane

  20. Future of uranium enrichment

    International Nuclear Information System (INIS)

    Hosmer, C.

    1981-01-01

    The increasing amount of separative work being done in government facilities to produce low-enriched uranium fuel for nuclear utilities again raises the question: should this business-type, industrial function be burned over the private industry. The idea is being looked at by the Reagan administration, but faces problems of national security as well as from the unique nature of the business. This article suggests that a joint government-private venture combining enriching, reprocessing, and waste disposal could be the answer. Further, a separate entity using advanced laser technology to deplete existing uranium tails and lease them for fertile blankets in breeder reactors might earn substantial revenues to help reduce the national debt

  1. South Australia, uranium enrichment

    International Nuclear Information System (INIS)

    1976-02-01

    The Report sets out the salient data relating to the establishment of a uranium processing centre at Redcliff in South Australia. It is conceived as a major development project for the Commonwealth, the South Australian Government and Australian Industry comprising the refining and enrichment of uranium produced from Australian mines. Using the data currently available in respect of markets, demand, technology and possible financial return from overseas sales, the project could be initiated immediately with hexafluoride production, followed rapidly in stages by enrichment production using the centrifuge process. A conceptual development plan is presented, involving a growth pattern that would be closely synchronised with the mining and production of yellowcake. The proposed development is presented in the form of an eight-and-half-year programme. Costs in this Report are based on 1975 values, unless otherwise stated. (Author)

  2. Proteomics and the dynamic plasma membrane

    DEFF Research Database (Denmark)

    Sprenger, Richard R; Jensen, Ole Nørregaard

    2010-01-01

    plasma membrane is of particular interest, by not only serving as a barrier between the "cell interior" and the external environment, but moreover by organizing and clustering essential components to enable dynamic responses to internal and external stimuli. Defining and characterizing the dynamic plasma...... the challenges in functional proteomic studies of the plasma membrane. We review the recent progress in MS-based plasma membrane proteomics by presenting key examples from eukaryotic systems, including mammals, yeast and plants. We highlight the importance of enrichment and quantification technologies required...... for detailed functional and comparative analysis of the dynamic plasma membrane proteome....

  3. Emerging insights into the roles of membrane tethers from analysis of whole organisms: The tip of an iceberg?

    Directory of Open Access Journals (Sweden)

    Wei Hong eToh

    2016-02-01

    Full Text Available Membrane tethers have been identified throughout different compartments of the endomembrane system. It is now well established that a number of membrane tethers mediate docking of membrane carriers in anterograde and retrograde transport and in regulating the organization of membrane compartments. Much of our information on membrane tethers have been obtained from the analysis of individual membrane tethers in cultured cells. In the future it will be important to better appreciate the network of interactions mediated by tethers and the potential co-ordination of their collective functions in vivo. There are now a number of studies which have analyzed membrane tethers in tissues and organisms which are providing new insights into the role of this class of membrane protein at the physiological level. Here we review recent advances in the understanding of the function of membrane tethers from knock outs (or knock downs in whole organisms and from mutations in tethers associated with disease.

  4. Distribution of Radioisotopes between Phytoplankton, Sediment and Sea Water in a Dialysis Compartment System

    International Nuclear Information System (INIS)

    Dawson, R.; Duursma, E.K.

    1976-01-01

    The distribution of the radioisotopes 36 Cl, 54 Mn, 59 Fe, 60 Co, 65 Zn, 90 Sr, 106 Ru, 109 Cd, 110 mAg, 137 Cs, 144 Ce, 147 Pm and 204 Tl between sea water, Mediterranean sediment in suspension, and the phytoplankton species Phaeodactylum tricornutum was studied by using a competitive technique in which the various phases were separated by dialysis membranes. The radioisotopes were introduced into the sea water compartment and the radionuclide uptake by sediment and phytoplankton occurred in the adjoining compartments after the isotopes had diffused through the membranes. The diffusion through membranes is time dependent and related to the hydrated ion radii of the elements in solution. Chelation of the elements by organic matter from sewage may hamper this diffusion, although the complexing molecules themselves can pass through the membrane. The laboratory experiments showed that the uptake of radionuclides by sediments and phytoplankton in suspension did not occur independently of each other but in competition relative to the different affinities to the sediment and phytoplankton and relative to the concentrations of the particulate materials themselves. On examination of the distribution coefficients, the isotopes 90Sr, 110m Ag, 204 Ti and in particular 109 Cd, had higher affinities towards Phaeodactylum tricornutum than towards the Mediterranean sediment. The isotopes 54 Mn, 60 Co and 137 Cs had lower distribution coefficients with the phytoplankton than with sediment and in the case of 59 Fe, 65 Zn, l06 Ru, l 4 Ce and 147 Pm, the distribution coefficients were similar for both phytoplankton and sediment. Taking into account that many more factors play a role in the natural aquatic environment, the distribution pattern between water, plankton and sediment in suspension can be approximated by calculating the percentage distribution in the 3 phases. Those percentages are dependent on 2 parameters, being the distribution coefficients and the concentrations of the

  5. CO2 Acquisition Membrane (CAM)

    Science.gov (United States)

    Mason, Larry W.; Way, J. Douglas; Vlasse, Marcus

    2003-01-01

    mechanisms. The Membrane Test Facility (MTF) has been developed to measure membrane permeance over a wide range of temperature and pressure. The facility uses two volume compartments separated by the membrane that are instrumented to measure temperature, delta pressure across the membrane, and gas composition. A thermal shroud supports and encloses the membrane, and provides temperature control. Methods were developed to determine membrane permeance using the first order decay of the pressure difference between the sealed compartments, using the total pressure for pure gases, and partial pressure of each species in gas mixtures. The technique provides an end-to-end measurement of gas permeance that includes concentration polarization effects. Experiments have shown that in addition to membrane permeance properties, the geometry and design of associated structures play an important role in how membrane systems will function on Mars.

  6. Membrane Protrusion Coarsening and Nanotubulation within Giant Unilamellar Vesicles

    KAUST Repository

    Węgrzyn, Ilona

    2011-11-16

    Hydrophobic side groups on a stimuli-responsive polymer, encapsulated within a single giant unilamellar vesicle, enable membrane attachment during compartment formation at elevated temperatures. We thermally modulated the vesicle through implementation of an IR laser via an optical fiber, enabling localized directed heating. Polymer-membrane interactions were monitored using confocal imaging techniques as subsequent membrane protrusions occurred and lipid nanotubes formed in response to the polymer hydrogel contraction. These nanotubes, bridging the vesicle membrane to the contracting hydrogel, were retained on the surface of the polymer compartment, where they were transformed into smaller vesicles in a process reminiscent of cellular endocytosis. This development of a synthetic vesicle system containing a stimuli-responsive polymer could lead to a new platform for studying inter/intramembrane transport through lipid nanotubes. © 2011 American Chemical Society.

  7. Well-leg compartment syndrome after gynecological laparoscopic surgery

    DEFF Research Database (Denmark)

    Boesgaard-Kjer, Diana H; Boesgaard-Kjer, Daniel; Kjer, Jens Jørgen

    2013-01-01

    Well-leg compartment syndrome in the lower extremities after surgery in the lithotomy position is a rare but severe complication requiring early diagnosis and intervention. Several circumstances predispose to this condition as a consequence of increased intra-compartmental pressure, such as posit...

  8. Compartment specific importance of glutathione during abiotic and biotic stress

    Directory of Open Access Journals (Sweden)

    Bernd eZechmann

    2014-10-01

    Full Text Available The tripeptide thiol glutathione (γ-L-glutamyl-L-cysteinyl-glycine is the most important sulfur containing antioxidant in plants and essential for plant defense against abiotic and biotic stress conditions. It is involved in the detoxification of reactive oxygen species, redox signaling, the modulation of defense gene expression and important for the regulation of enzymatic activities. Even though changes in glutathione contents are well documented in plants and its roles in plant defense are well established, still too little is known about its compartment specific importance during abiotic and biotic stress conditions. Due to technical advances in the visualization of glutathione and the redox state of plants through microscopical methods some progress was made in the last few years in studying the importance of subcellular glutathione contents during stress conditions in plants. This review summarizes the data available on compartment specific importance of glutathione in the protection against abiotic and biotic stress conditions such as high light stress, exposure to cadmium, drought, and pathogen attack (Pseudomonas, Botrytis, Tobacco Mosaic Virus. The data will be discussed in connection with the subcellular accumulation of ROS during these conditions and glutathione synthesis which are both highly compartment specific (e.g. glutathione synthesis takes place in chloroplasts and the cytosol. Thus this review will reveal the compartment specific importance of glutathione during abiotic and biotic stress conditions.

  9. Talofibular compartment of the ankle joint after recent ankle sprain

    International Nuclear Information System (INIS)

    Lindstrand, A.; Mortensson, W.; Norman, O.

    1978-01-01

    The validity of predicting the condition of the anterior talofibular ligament from the shape of the lateral compartment of the ankle joint was investigated in patients with recent ankle sprain. The diagnostic value of the method was found to be restricted. (Auth.)

  10. Volume of the effect compartment in simulations of neuromuscular block

    NARCIS (Netherlands)

    Nigrovic, Vladimir; Proost, Johannes H.; Amann, Anton; Bhatt, Shashi B.

    2005-01-01

    Background: The study examines the role of the volume of the effect compartment in simulations of neuromuscular block (NMB) produced by nondepolarizing muscle relaxants. Methods: The molar amount of the postsynaptic receptors at the motor end plates in muscle was assumed constant; the apparent

  11. A wolf in wolf's clothing the abdominal compartment syndrome

    African Journals Online (AJOL)

    abdomen. These findings are consistent with the diagnosis of intra-abdominal compartment syndrome. In 1 case trauma was remote from the abdomen .... although they tend to develop most often in those who have undergone major vascular operations or suffered abdominal trauma. The effects of the pressure on the bowel ...

  12. "Compartment"-syndrom på underben, atypisk traumemekanisme

    DEFF Research Database (Denmark)

    Larsen, Michael H; Nielsen, Henrik Toft; Wester, Jens Ulrik

    2003-01-01

    Acute compartment syndrome (CS) is a limb threatening condition which warrants emergency treatment. We describe a case of a 37-year-old man with acute CS developed without major trauma. Early diagnosis and prompt treatment by decompressive fasciotomy is of vital importance in order to preserve limb...

  13. Surgical treatment for ~brain compartment syndrome' in children ...

    African Journals Online (AJOL)

    Objectives. Traumatic brain injury accounts for a high percentage of deaths in children. Raised intracranial pressure (ICP) due to brain swelling within the closed compartment of the skull leads to death or severe neurological disability if not effectively treated. We report our experience with 12 children who presented with ...

  14. Intraabdominal Compartment Syndrome Complicating Transurethral Resection of Bladder Tumor

    Directory of Open Access Journals (Sweden)

    Sachin Narain

    2012-01-01

    Full Text Available Abdominal compartment syndrome can result from many different causes. We present a case where this dangerous syndrome occurred in the operating room during a transurethral resection of a bladder tumor. It was initially recognized by an elevation in the peak inspiratory pressure. We report the typical physiologic changes that occur with this syndrome and its treatment options.

  15. The anammoxosome: an intracytoplasmic compartment in anammox bacteria

    NARCIS (Netherlands)

    Niftrik, L.A.M.P. van; Fuerst, J.A.; Damste, J.S.S.; Kuenen, J.G.; Jetten, M.S.M.; Strous, M.

    2004-01-01

    Anammox bacteria belong to the phylum Planctomycetes and perform anaerobic ammonium oxidation (anammox); they oxidize ammonium with nitrite as the electron acceptor to yield dinitrogen gas. The anammox reaction takes place inside the anammoxosome: an intracytoplasmic compartment bounded by a single

  16. The anammoxosome : An intracytoplasmic compartment in anammox bacteria

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Niftrik, L.A. van; Fuerst, J.A.; Kuenen, J.G.; Jetten, M.S.M.; Strous, M.

    2004-01-01

    Anammox bacteria belong to the phylum Planctomycetes and perform anaerobic ammonium oxidation (anammox); they oxidize ammonium with nitrite as the electron acceptor to yield dinitrogen gas. The anammox reaction takes place inside the anammoxosome: an intracytoplasmic compartment bounded by a single

  17. Compartment syndrome and popliteal vascular injury complicating unicompartmental knee arthroplasty

    NARCIS (Netherlands)

    Kort, Nanne Pieter; Van Raay, Jos J. J. A. M.; van Horn, Jim R.

    Popliteal vascular injury and the compartment syndrome of the leg are rare but important complications of knee arthroplasties. Early diagnosis and treatment are of paramount importance in preventing the devastating complications of these conditions. To our knowledge, these complications have not

  18. Two-Compartment Pharmacokinetic Models for Chemical Engineers

    Science.gov (United States)

    Kanneganti, Kumud; Simon, Laurent

    2011-01-01

    The transport of potassium permanganate between two continuous-stirred vessels was investigated to help chemical and biomedical engineering students understand two-compartment pharmacokinetic models. Concepts of modeling, mass balance, parameter estimation and Laplace transform were applied to the two-unit process. A good agreement was achieved…

  19. 14 CFR 121.314 - Cargo and baggage compartments.

    Science.gov (United States)

    2010-01-01

    ...: (a) Each Class C or Class D compartment, as defined in § 25.857 of this Chapter in effect on June 16, 1986 (see Appendix L to this part), that is greater than 200 cubic feet in volume must have ceiling and sidewall liner panels which are constructed of: (1) Glass fiber reinforced resin; (2) Materials which meet...

  20. Ward Round - Late Presentation of Acute Compartment Syndrome in ...

    African Journals Online (AJOL)

    following the course of ibuprofen mentioned. Twelve days after admission he started to complain of increasing pain and tightness in his left thigh. Sensation and motor function. Ward Round - Late Presentation of Acute. Compartment Syndrome in the Thigh. University of Malawi, College of Medicine, Department of Surgery,.

  1. The density of GM1-enriched lipid rafts correlates inversely with the efficiency of transfection mediated by cationic liposomes.

    Science.gov (United States)

    Kovács, Tamás; Kárász, Andrea; Szöllosi, János; Nagy, Peter

    2009-08-01

    Although cationic liposome-mediated transfection has become a standard procedure, the mechanistic details of the process are unknown. It has been suggested that endocytic uptake of lipoplexes is efficient, and transfectability is largely determined by later steps. In this article, we stained GM1-enriched membrane microdomains, a subclass of lipid rafts, with subunit B of cholera toxin and correlated transfection efficiency with their density by quantitatively evaluating microscopic images. We found a strong anticorrelation between the density of GM1-enriched membrane microdomains and the efficacy of transfection monitored by measuring the expression level of GFP in different cell lines transfected by lipofection using two different transfection agents. These findings imply that GM1-enriched membrane microdomains interfere with the process of lipofection. The blocked step must be endocytosis since the accumulation of fluorescently labeled plasmids was lower in cells with high content of GM1-enriched membrane microdomains. Such a correlation was not observed in cells transfected by electroporation. By comparing the efficiency of lipofection in several cell lines we found that those with a high density of GM1-enriched membrane microdomains were the most resistant to transfection. We conclude that the inhibition of lipofection by GM1-enriched membrane microdomains is a general rule, and that endocytosis of lipoplexes can be rate limiting in cells with high density of GM1-enriched membrane rafts. Copyright 2009 International Society for Advancement of Cytometry.

  2. Silver contamination on abiotic and biotic compartments of Nahuel Huapi National Park lakes, Patagonia, Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro Guevara, Sergio; Arribere, Maria; Bubach, Debora; Vigliano, Pablo; Rizzo, Andrea; Alonso, Marcelo; Sanchez, Ricardo

    2005-01-05

    The Ag contents of abiotic and biotic compartments of different lakes of Nahuel Huapi National Park, Patagonia, Argentina were analyzed. The water bodies studied were lakes Nahuel Huapi, Moreno, Escondido, Espejo Chico and Traful, the latter chosen as a reference lake. The Ag concentration profiles of short sediment cores, dated by {sup 210}Pb and {sup 137}Cs techniques, were analyzed, as well as suspended load collected from three sites of lake Nahuel Huapi. The biota studied were the native mussel Diplodon chilensis (digestive gland and total soft tissues pooled samples) and five species of fish, two native and three introduced (liver and muscle pooled samples). Ag contents were determined by Instrumental Neutron Activation Analysis (INAA). The upper layers of the sediment cores sampled in lake Nahuel Huapi were enriched in Ag contents compared to deep layers in accumulation periods corresponding to the second half of the 20th century, but this enrichment was neither observed in the reference lake Traful, nor in lakes Espejo Chico and Escondido. Ag was enriched over background level (0.1 {mu}g g{sup -1}) also in suspended load collected in lake Nahuel Huapi. Ag fluxes to sediments were computed for suspended load and enriched sediment core layers. Highest Ag fluxes, from 350 to 470 {mu}g m{sup -2} year{sup -1}, were measured in Nahuel Huapi near the site where the liquid effluents of the Bariloche city sewage treatment plant are released to the lake. The spatial distribution of the other Ag fluxes suggests that this is the main source of Ag to lake Nahuel Huapi and lateral transport occurs within the water body. Ag concentrations on biota samples were consistent with these conclusions. Mussels collected in lake Nahuel Huapi showed higher Ag concentrations than in the other lakes, especially when compared to lake Traful. Ag contents in mussels were strongly associated with sediment intake, but enriched probably due to sediment grain size sorting during the intake

  3. Silver contamination on abiotic and biotic compartments of Nahuel Huapi National Park lakes, Patagonia, Argentina

    International Nuclear Information System (INIS)

    Ribeiro Guevara, Sergio; Arribere, Maria; Bubach, Debora; Vigliano, Pablo; Rizzo, Andrea; Alonso, Marcelo; Sanchez, Ricardo

    2005-01-01

    The Ag contents of abiotic and biotic compartments of different lakes of Nahuel Huapi National Park, Patagonia, Argentina were analyzed. The water bodies studied were lakes Nahuel Huapi, Moreno, Escondido, Espejo Chico and Traful, the latter chosen as a reference lake. The Ag concentration profiles of short sediment cores, dated by 210 Pb and 137 Cs techniques, were analyzed, as well as suspended load collected from three sites of lake Nahuel Huapi. The biota studied were the native mussel Diplodon chilensis (digestive gland and total soft tissues pooled samples) and five species of fish, two native and three introduced (liver and muscle pooled samples). Ag contents were determined by Instrumental Neutron Activation Analysis (INAA). The upper layers of the sediment cores sampled in lake Nahuel Huapi were enriched in Ag contents compared to deep layers in accumulation periods corresponding to the second half of the 20th century, but this enrichment was neither observed in the reference lake Traful, nor in lakes Espejo Chico and Escondido. Ag was enriched over background level (0.1 μg g -1 ) also in suspended load collected in lake Nahuel Huapi. Ag fluxes to sediments were computed for suspended load and enriched sediment core layers. Highest Ag fluxes, from 350 to 470 μg m -2 year -1 , were measured in Nahuel Huapi near the site where the liquid effluents of the Bariloche city sewage treatment plant are released to the lake. The spatial distribution of the other Ag fluxes suggests that this is the main source of Ag to lake Nahuel Huapi and lateral transport occurs within the water body. Ag concentrations on biota samples were consistent with these conclusions. Mussels collected in lake Nahuel Huapi showed higher Ag concentrations than in the other lakes, especially when compared to lake Traful. Ag contents in mussels were strongly associated with sediment intake, but enriched probably due to sediment grain size sorting during the intake processes. Evidence of food

  4. Performance of integrated bioelectrochemical membrane reactor: Energy recovery, pollutant removal and membrane fouling alleviation

    Science.gov (United States)

    Dong, Yue; He, Weihua; Li, Chao; Liang, Dandan; Qu, Youpeng; Han, Xiaoyu; Feng, Yujie

    2018-04-01

    A novel hybrid bioelectrochemical membrane reactor with integrated microfiltration membrane as the separator between electrodes is developed for domestic wastewater treatment. After accumulation of biofilm, the organic pollutants are mainly degraded in anodic compartment, and microfiltration membrane blocks the adverse leakage of dissolved oxygen from aerated cathodic compartment. The maximum system power output is restricted by gas-water ratio following a Monod-like relationship. Within the tested gas-water ratios ranging from 0.6 to 42.9, the half-saturation constant (KQ) is 5.9 ± 0.9 with a theoretic maximum power density of 20.4 ± 1.0 W m-3. Energy balance analysis indicates an appropriate gas-water ratio regulation (from 2.3 to 28.6) for cathodic compartment is necessary to obtain positive energy output for the system. A maximum net electricity output is 9.09 × 10-3 kWh m-3 with gas-water ratio of 17.1. Notably, the system achieves the chemical oxygen demand removal of 98.3 ± 0.3%, ammonia nitrogen removal of 99.6 ± 0.1%, and total nitrogen removal of 80.0 ± 0.9%. This work verifies an effective integration of microfiltration membrane into bioelectrochemical system as separator for high-quality effluent and provides an insight into the operation and regulation of biocathode system for effective electrical energy output.

  5. Acute lumbar paraspinal compartment syndrome: a systematic review.

    Science.gov (United States)

    Alexander, William; Low, Nelson; Pratt, George

    2018-01-08

    While still a rare entity, acute lumbar paraspinal compartment syndrome has an increasing incidence. Similar to other compartment syndromes, acute lumbar paraspinal compartment syndrome is defined by raised pressure within a closed fibro-osseous space, limiting tissue perfusion within that space. The resultant tissue ischaemia presents as acute pain, and if left untreated, it may result in permanent tissue damage. A literature search of 'paraspinal compartment syndrome' revealed 21 articles. The details from a case encountered by the authors are also included. A common data set was extracted, focusing on demographics, aetiology, clinical features, management and outcomes. There are 23 reported cases of acute compartment syndrome. These are typically caused by weight-lifting exercises, but may also result from other exercises, direct trauma or non-spinal surgery. Pain, tenderness and paraspinal paraesthesia are key clinical findings. Serum creatine kinase, magnetic resonance imaging and intracompartment pressure measurement confirm the diagnosis. Half of the reported cases have been managed with surgical fasciotomy, and these patients have all had good outcomes relative to those managed with conservative measures with or without hyperbaric oxygen therapy. These good outcomes were despite significant delays to operative intervention. The diagnostic uncertainty and subsequent delay to fasciotomy result from the rarity of this disease entity, and a high level of suspicion is recommended in the appropriate setting. This is particularly true in light of the current popularity of extreme weight lifting in non-professional athletes. Operative intervention is strongly recommended in all cases based on the available evidence. © 2018 Royal Australasian College of Surgeons.

  6. Lift-and-fill face lift: integrating the fat compartments.

    Science.gov (United States)

    Rohrich, Rod J; Ghavami, Ashkan; Constantine, Fadi C; Unger, Jacob; Mojallal, Ali

    2014-06-01

    Recent discovery of the numerous fat compartments of the face has improved our ability to more precisely restore facial volume while rejuvenating it through differential superficial musculoaponeurotic system treatment. Incorporation of selective fat compartment volume restoration along with superficial musculoaponeurotic system manipulation allows for improved control in recontouring while addressing one of the key problems in facial aging, namely, volume deflation. This theory was evaluated by assessing the contour changes from simultaneous face "lifting" and "filling" through fat compartment-guided facial fat transfer. A review of 100 face-lift patients was performed. All patients had an individualized component face lift with fat grafting to the nasolabial fold, deep malar, and high/lateral malar fat compartment locations. Photographic analysis using a computer program was conducted on oblique facial views preoperatively and postoperatively, to obtain the most projected malar contour point. Two independent observers visually evaluated the malar prominence and nasolabial fold improvements based on standardized photographs. Nasolabial fold improved by at least one grade in 81 percent and by over one grade in 11 percent. Malar prominence average projection increase was 13.47 percent and the average amount of lift was 12.24 percent. The malar prominence score improved by at least one grade in 62 percent of the patients postoperatively, and 9 percent had a greater than one grade improvement. Twenty-eight percent of the patients had a convex malar prominence postoperatively compared with 6 percent preoperatively. Malar prominence improved by at least one grade in 63 percent and by over one grade in 10 percent. The lift-and-fill face lift merges two key concepts in facial rejuvenation: (1) effective tissue manipulation by means of lifting and tightening in differential vectors according to original facial asymmetry and shape; and (2) selective fat compartment filling

  7. Membrane shape modulates transmembrane protein distribution.

    Science.gov (United States)

    Aimon, Sophie; Callan-Jones, Andrew; Berthaud, Alice; Pinot, Mathieu; Toombes, Gilman E S; Bassereau, Patricia

    2014-01-27

    Although membrane shape varies greatly throughout the cell, the contribution of membrane curvature to transmembrane protein targeting is unknown because of the numerous sorting mechanisms that take place concurrently in cells. To isolate the effect of membrane shape, we used cell-sized giant unilamellar vesicles (GUVs) containing either the potassium channel KvAP or the water channel AQP0 to form membrane nanotubes with controlled radii. Whereas the AQP0 concentrations in flat and curved membranes were indistinguishable, KvAP was enriched in the tubes, with greater enrichment in more highly curved membranes. Fluorescence recovery after photobleaching measurements showed that both proteins could freely diffuse through the neck between the tube and GUV, and the effect of each protein on membrane shape and stiffness was characterized using a thermodynamic sorting model. This study establishes the importance of membrane shape for targeting transmembrane proteins and provides a method for determining the effective shape and flexibility of membrane proteins. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Isolation of Protein Storage Vacuoles and Their Membranes.

    Science.gov (United States)

    Shimada, Tomoo; Hara-Nishimura, Ikuko

    2017-01-01

    Protein-storage vacuoles (PSVs) are specialized vacuoles that sequester large amounts of storage proteins. During seed development, PSVs are formed de novo and/or from preexisting lytic vacuoles. Seed PSVs can be subdivided into four distinct compartments: membrane, globoid, matrix, and crystalloid. In this chapter, we introduce easy methods for isolation of PSVs and their membranes from pumpkin seeds. These methods facilitate the identification and characterization of PSV components.

  9. Localization of HCMV UL33 and US27 in endocytic compartments and viral membranes

    DEFF Research Database (Denmark)

    Fraile-Ramos, Alberto; Pelchen-Matthews, Annegret; Kledal, Thomas N

    2002-01-01

    and undergoes constitutive endocytosis and recycling. Here we studied the cellular distributions and trafficking of two other human cytomegalovirus chemokine receptor-like proteins, UL33 and US27, in transfected and human cytomegalovirus-infected cells. Immunofluorescence staining indicated that UL33 and US27......The human cytomegalovirus genome encodes four putative seven transmembrane domain chemokine receptor-like proteins. Although important in viral pathogenesis, little is known about the properties or functions of these proteins. We previously reported that US28 is located in endocytic vesicles......27 undergoes endocytosis. By immunogold labeling of cryosections and electron microscopy, UL33 was seen to localize to multivesicular bodies (MVBs or multivesicular endosomes). Electron microscopy analysis of human cytomegalovirus-infected cells showed that most virus particles wrapped individually...

  10. Cell Membrane Transport Mechanisms: Ion Channels and Electrical Properties of Cell Membranes.

    Science.gov (United States)

    Kulbacka, Julita; Choromańska, Anna; Rossowska, Joanna; Weżgowiec, Joanna; Saczko, Jolanta; Rols, Marie-Pierre

    2017-01-01

    Cellular life strongly depends on the membrane ability to precisely control exchange of solutes between the internal and external (environmental) compartments. This barrier regulates which types of solutes can enter and leave the cell. Transmembrane transport involves complex mechanisms responsible for passive and active carriage of ions and small- and medium-size molecules. Transport mechanisms existing in the biological membranes highly determine proper cellular functions and contribute to drug transport. The present chapter deals with features and electrical properties of the cell membrane and addresses the questions how the cell membrane accomplishes transport functions and how transmembrane transport can be affected. Since dysfunctions of plasma membrane transporters very often are the cause of human diseases, we also report how specific transport mechanisms can be modulated or inhibited in order to enhance the therapeutic effect.

  11. Membrane transport of anandamide through resealed human red blood cell membranes

    DEFF Research Database (Denmark)

    Bojesen, I.N.; Hansen, Harald S.

    2005-01-01

    The use of resealed red blood cell membranes (ghosts) allows the study of the transport of a compound in a nonmetabolizing system with a biological membrane. Transmembrane movements of anandamide (N-arachidonoylethanolamine, arachidonoylethanolamide) have been studied by exchange efflux experiments...... at 0°C and pH 7.3 with albumin-free and albumin-filled human red blood cell ghosts. The efflux kinetics is biexponential and is analyzed in terms of compartment models. The distribution of anandamide on the membrane inner to outer leaflet pools is determined to be 0.275 ± 0.023, and the rate constant...... of unidirectional flux from inside to outside is 0.361 ± 0.023 s. The rate constant of unidirectional flux from the membrane to BSA in the medium ([BSA]) increases with the square root of [BSA] in accordance with the theory of an unstirred layer around ghosts. Anandamide passed through the red blood cell membrane...

  12. Beta activity of enriched uranium

    International Nuclear Information System (INIS)

    Nambiar, P.P.V.J.; Ramachandran, V.

    1975-01-01

    Use of enriched uranium as reactor fuel necessitates its handling in various forms. For purposes of planning and organising radiation protection measures in enriched uranium handling facilities, it is necessary to have a basic knowledge of the radiation status of enriched uranium systems. The theoretical variations in beta activity and energy with U 235 enrichment are presented. Depletion is considered separately. Beta activity build up is also studied for two specific enrichments, in respect of which experimental values for specific alpha activity are available. (author)

  13. Evolution and development of model membranes for physicochemical and functional studies of the membrane lateral heterogeneity.

    Science.gov (United States)

    Morigaki, Kenichi; Tanimoto, Yasushi

    2018-03-14

    One of the main questions in the membrane biology is the functional roles of membrane heterogeneity and molecular localization. Although segregation and local enrichment of protein/lipid components (rafts) have been extensively studied, the presence and functions of such membrane domains still remain elusive. Along with biochemical, cell observation, and simulation studies, model membranes are emerging as an important tool for understanding the biological membrane, providing quantitative information on the physicochemical properties of membrane proteins and lipids. Segregation of fluid lipid bilayer into liquid-ordered (Lo) and liquid-disordered (Ld) phases has been studied as a simplified model of raft in model membranes, including giant unilamellar vesicles (GUVs), giant plasma membrane vesicles (GPMVs), and supported lipid bilayers (SLB). Partition coefficients of membrane proteins between Lo and Ld phases were measured to gauze their affinities to lipid rafts (raftophilicity). One important development in model membrane is patterned SLB based on the microfabrication technology. Patterned Lo/Ld phases have been applied to study the partition and function of membrane-bound molecules. Quantitative information of individual molecular species attained by model membranes is critical for elucidating the molecular functions in the complex web of molecular interactions. The present review gives a short account of the model membranes developed for studying the lateral heterogeneity, especially focusing on patterned model membranes on solid substrates. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Integrated design of SIGMA uranium enrichment plants

    International Nuclear Information System (INIS)

    Rivarola, Martin E.; Brasnarof, Daniel O.

    1999-01-01

    In the present work, we describe a preliminary analysis of the design feedbacks in a Uranium Enrichment Plant, using the SIGMA concept. Starting from the result of this analysis, a computer code has been generated, which allows finding the optimal configurations of plants, for a fixed production rate. The computer code developed includes the model of the Thermohydraulic loop of a SIGMA module. The model contains numerical calculations of the main components of the circuit. During the calculations, the main components are dimensioned, for a posterior cost compute. The program also makes an estimation of the enrichment gain of the porous membrane, for each separation stage. Once the dimensions of the main components are known, using the enrichment cascade calculation, the capital and operation costs of the plant could be determined. At this point it is simple to calculate a leveled cost of the Separative Work Unit (SWU). A numerical optimizer is also included in the program. This optimizer finds the optimal cascade configuration, for a given set of design parameters. The whole-integrated program permits to investigate in detail the feedback in the component design. Therefore, the sensibility of the more relevant parameters can be computed, with respect of the economical variables of the plant. (author)

  15. Does evaluation of the ligamentous compartment enhance diagnostic utility of sacroiliac joint MRI in axial spondyloarthritis?

    DEFF Research Database (Denmark)

    Weber, Ulrich; Maksymowych, Walter P; Chan, Stanley M

    2015-01-01

    in the ligamentous compartment and their potential diagnostic utility in axial SpA. We therefore aimed to evaluate the ligamentous compartment on sacroiliac joint MRI for lesion distribution and potential incremental value towards diagnosis of SpA over and above the traditional assessment of the cartilaginous...... and ligamentous compartment. The incremental value of evaluating the ligamentous additionally to the cartilaginous compartment alone for diagnosis of SpA was graded qualitatively. We determined the lesion distribution between the two compartments, and the impact of the ligamentous compartment evaluation...... on diagnostic utility. RESULTS: MRI bone marrow lesions solely in the ligamentous compartment in the absence of lesions in the cartilaginous compartment were reported in just 0-2.0/0-4.0 % (BME/fat metaplasia) of all subjects. Additional assessment of the ligamentous compartment was regarded as essential...

  16. Steric exclusion and protein conformation determine the localization of plasma membrane transporters

    NARCIS (Netherlands)

    Bianchi, Frans; Syga, Łukasz; Moiset, Gemma; Spakman, Dian; Schavemaker, Paul E; Punter, Christiaan M; Seinen, Anne-Bart; van Oijen, Antoine M; Robinson, Andrew; Poolman, Bert

    2018-01-01

    The plasma membrane (PM) of Saccharomyces cerevisiae contains membrane compartments, MCC/eisosomes and MCPs, named after the protein residents Can1 and Pma1, respectively. Using high-resolution fluorescence microscopy techniques we show that Can1 and the homologous transporter Lyp1 are able to

  17. Blueprint for domestic uranium enrichment

    International Nuclear Information System (INIS)

    1981-01-01

    The AEC advisory committee on domestic production of uranium enrichment has studied for more than a year how to achieve the domestic enrichment of uranium by the construction and operation of a commercial enriching plant using centrifugal separation method, and the report was submitted to the Atomic Energy Commission on August 18, 1980. Japan has depended wholly on overseas services for her uranium enrichment needs, but the development of domestic enrichment has been carried on in parallel. The AEC decided to construct a uranium enrichment pilot plant using centrifuges, and it has been forwarded as a national project. The plant is operated by the Power Reactor and Nuclear Fuel Development Corp. since 1979. The capacity of the plant will be raised to approximately 75 ton SWU a year. The centrifuges already operated have provided the first delivery of fuel of about 1 ton for the ATR ''Fugen''. The demand-supply balance of uranium enrichment service, the significance of the domestic enrichment of uranium, the evaluation of uranium enrichment technology, the target for domestic enrichment plan, the measures to promote domestic uranium enrichment, and the promotion of the construction of a demonstration plant are reported. (Kako, I.)

  18. Uranium enrichment by gas centrifuge

    International Nuclear Information System (INIS)

    Heriot, I.D.

    1988-01-01

    After recalling the physical principles and the techniques of centrifuge enrichment the report describes the centrifuge enrichment programmes of the various countries concerned and compares this technology with other enrichment technologies like gaseous diffusion, laser, aerodynamic devices and chemical processes. The centrifuge enrichment process is said to be able to replace with advantage the existing enrichment facilities in the short and medium term. Future prospects of the process are also described, like recycled uranium enrichment and economic improvements; research and development needs to achieve the economic prospects are also indicated. Finally the report takes note of the positive aspect of centrifuge enrichment as far as safeguards and nuclear safety are concerned. 27 figs, 113 refs

  19. Radiometric enrichment of nonradioactive ores

    International Nuclear Information System (INIS)

    Mokrousov, V.A.; Lileev, V.A.

    1979-01-01

    Considered are the methods of mineral enrichment based on the use of the radioation of various types. The physical essence of enrichment processes is presented, their classification is given. Described are the ore properties influencing the efficiency of radiometric enrichment, methods of the properties study and estimation of ore enrichment. New possibilities opened by radiometric enrichment in the technology of primary processing of mineral raw materials are elucidated. A considerable attention is paid to the main and auxiliary equipment for radiometric enrichment. The foundations of the safety engineering are presented in a brief form. Presented are also results of investigations and practical works in the field of enrichment of ores of non-ferrous, ferrous and non-metallic minerals with the help of radiometric methods

  20. 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

  1. 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.

  2. Atomistic simulations of anionic Au-144(SR)(60) nanoparticles interacting with asymmetric model lipid membranes

    DEFF Research Database (Denmark)

    Heikkila, E.; Martinez-Seara, H.; Gurtovenko, A. A.

    2014-01-01

    whose lipid composition and transmembrane distribution are to a large extent consistent with real plasma membranes of eukaryotic cells. To this end, we use a model system which comprises two cellular compartments, extracellular and cytosolic, divided by two asymmetric lipid bilayers. The simulations...... clearly show that AuNP- attaches to the extracellular membrane surface within a few tens of nanoseconds, while it avoids contact with the membrane on the cytosolic side. This behavior stems from several factors. In essence, when the nanoparticle interacts with lipids in the extracellular compartment...

  3. The world enrichment market

    International Nuclear Information System (INIS)

    Gunter, L.; McCants, C.; Rutkowski, E.

    1991-01-01

    The enrichment market can be divided into two periods: the near-term market (1991 to 1995) and the long-term market (1995 and beyond). The near-term market is characterized by limited unfilled requirements of 4% per year, to be supplied by national stockpiles and excess inventories. This low-cost material will be drawn down by about 1993, causing a subsequent price rise. As the price rises, primary supplier activity is expected to increase. In the near-term, two contracting activities are apparent: spot; and intermediate-term. The current spot market is expected to last until available low cost inventories are drawn down. Recently, in attempts to gain market share, suppliers have offered attractively priced intermediate-term (3 year) contracts for 1996 to 1998. While a small spot market will continue after 1995, it is anticipated that utilities will prefer a mix of medium- and long-term (5 to 10 year) contracts from primary suppliers for most of their enrichment requirements. As national stockpiles and utility inventories are consumed, low-cost supply available to the spot market is expected to diminish. Consequently, with little low-cost supply available, the only apparent source of material will be from primary suppliers, and the resulting competition over market share is expected to be intense. (author)

  4. Motif enrichment tool.

    Science.gov (United States)

    Blatti, Charles; Sinha, Saurabh

    2014-07-01

    The Motif Enrichment Tool (MET) provides an online interface that enables users to find major transcriptional regulators of their gene sets of interest. MET searches the appropriate regulatory region around each gene and identifies which transcription factor DNA-binding specificities (motifs) are statistically overrepresented. Motif enrichment analysis is currently available for many metazoan species including human, mouse, fruit fly, planaria and flowering plants. MET also leverages high-throughput experimental data such as ChIP-seq and DNase-seq from ENCODE and ModENCODE to identify the regulatory targets of a transcription factor with greater precision. The results from MET are produced in real time and are linked to a genome browser for easy follow-up analysis. Use of the web tool is free and open to all, and there is no login requirement. ADDRESS: http://veda.cs.uiuc.edu/MET/. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  5. Functionalization of a Membrane Sublayer Using Reverse Filtration of Enzymes and Dopamine Coating

    DEFF Research Database (Denmark)

    Luo, Jianquan; Meyer, Anne S.; Mateiu, Ramona Valentina

    2014-01-01

    High permeability, high enzyme loading, and strong antifouling ability are the desired features for a biocatalytic membrane to be used in an enzymatic membrane reactor (EMR). To achieve these goals, the membrane sublayer was enriched with laccase by reverse filtration in this case, and the result......High permeability, high enzyme loading, and strong antifouling ability are the desired features for a biocatalytic membrane to be used in an enzymatic membrane reactor (EMR). To achieve these goals, the membrane sublayer was enriched with laccase by reverse filtration in this case...

  6. Extracellular Tau Oligomers Induce Invasion of Endogenous Tau into the Somatodendritic Compartment and Axonal Transport Dysfunction

    Science.gov (United States)

    Swanson, Eric; Breckenridge, Leigham; McMahon, Lloyd; Som, Sreemoyee; McConnell, Ian; Bloom, George S.

    2017-01-01

    Aggregates composed of the microtubule associated protein, tau, are a hallmark of Alzheimer’s disease and non-Alzheimer’s tauopathies. Extracellular tau can induce the accumulation and aggregation of intracellular tau, and tau pathology can be transmitted along neural networks over time. There are six splice variants of central nervous system tau, and various oligomeric and fibrillar forms are associated with neurodegeneration in vivo. The particular extracellular forms of tau capable of transferring tau pathology from neuron to neuron remain ill defined, however, as do the consequences of intracellular tau aggregation on neuronal physiology. The present study was undertaken to compare the effects of extracellular tau monomers, oligomers, and filaments comprising various tau isoforms on the behavior of cultured neurons. We found that 2N4R or 2N3R tau oligomers provoked aggregation of endogenous intracellular tau much more effectively than monomers or fibrils, or of oligomers made from other tau isoforms, and that a mixture of all six isoforms most potently provoked intracellular tau accumulation. These effects were associated with invasion of tau into the somatodendritic compartment. Finally, we observed that 2N4R oligomers perturbed fast axonal transport of membranous organelles along microtubules. Intracellular tau accumulation was often accompanied by increases in the run length, run time and instantaneous velocity of membranous cargo. This work indicates that extracellular tau oligomers can disrupt normal neuronal homeostasis by triggering axonal tau accumulation and loss of the polarized distribution of tau, and by impairing fast axonal transport. PMID:28482642

  7. Biocompatible click chemistry enabled compartment-specific pH measurement inside E. coli.

    Science.gov (United States)

    Yang, Maiyun; Jalloh, Abubakar S; Wei, Wei; Zhao, Jing; Wu, Peng; Chen, Peng R

    2014-09-19

    Bioorthogonal reactions, especially the Cu(I)-catalysed azide-alkyne cycloaddition, have revolutionized our ability to label and manipulate biomolecules under living conditions. The cytotoxicity of Cu(I) ions, however, has hindered the application of this reaction in the internal space of living cells. By systematically surveying a panel of Cu(I)-stabilizing ligands in promoting protein labelling within the cytoplasm of Escherichia coli, we identify a highly efficient and biocompatible catalyst for intracellular modification of proteins by azide-alkyne cycloaddition. This reaction permits us to conjugate an environment-sensitive fluorophore site specifically onto HdeA, an acid-stress chaperone that adopts pH-dependent conformational changes, in both the periplasm and cytoplasm of E. coli. The resulting protein-fluorophore hybrid pH indicators enable compartment-specific pH measurement to determine the pH gradient across the E. coli cytoplasmic membrane. This construct also allows the measurement of E. coli transmembrane potential, and the determination of the proton motive force across its inner membrane under normal and acid-stress conditions.

  8. Enhancing Membrane Protein Identification Using a Simplified Centrifugation and Detergent-Based Membrane Extraction Approach.

    Science.gov (United States)

    Zhou, Yanting; Gao, Jing; Zhu, Hongwen; Xu, Jingjing; He, Han; Gu, Lei; Wang, Hui; Chen, Jie; Ma, Danjun; Zhou, Hu; Zheng, Jing

    2018-02-20

    Membrane proteins may act as transporters, receptors, enzymes, and adhesion-anchors, accounting for nearly 70% of pharmaceutical drug targets. Difficulties in efficient enrichment, extraction, and solubilization still exist because of their relatively low abundance and poor solubility. A simplified membrane protein extraction approach with advantages of user-friendly sample processing procedures, good repeatability and significant effectiveness was developed in the current research for enhancing enrichment and identification of membrane proteins. This approach combining centrifugation and detergent along with LC-MS/MS successfully identified higher proportion of membrane proteins, integral proteins and transmembrane proteins in membrane fraction (76.6%, 48.1%, and 40.6%) than in total cell lysate (41.6%, 16.4%, and 13.5%), respectively. Moreover, our method tended to capture membrane proteins with high degree of hydrophobicity and number of transmembrane domains as 486 out of 2106 (23.0%) had GRAVY > 0 in membrane fraction, 488 out of 2106 (23.1%) had TMs ≥ 2. It also provided for improved identification of membrane proteins as more than 60.6% of the commonly identified membrane proteins in two cell samples were better identified in membrane fraction with higher sequence coverage. Data are available via ProteomeXchange with identifier PXD008456.

  9. Modular enrichment measurement system for in-situ enrichment assay

    International Nuclear Information System (INIS)

    Stewart, J.P.

    1976-01-01

    A modular enrichment measurement system has been designed and is in operation within General Electric's Nuclear Fuel Fabrication Facility for the in-situ enrichment assay of uranium-bearing materials in process containers. This enrichment assay system, which is based on the ''enrichment meter'' concept, is an integral part of the site's enrichment control program and is used in the in-situ assay of the enrichment of uranium dioxide (UO 2 ) powder in process containers (five gallon pails). The assay system utilizes a commercially available modular counting system and a collimnator designed for compatability with process container transport lines and ease of operator access. The system has been upgraded to include a microprocessor-based controller to perform system operation functions and to provide data acquisition and processing functions. Standards have been fabricated and qualified for the enrichment assay of several types of uranium-bearing materials, including UO 2 powders. The assay system has performed in excess of 20,000 enrichment verification measurements annually and has significantly contributed to the facility's enrichment control program

  10. Air quality inside the passenger compartment of a bus.

    Science.gov (United States)

    Conceição, E Z; Silva, M C; Viegas, D X

    1997-01-01

    The indoor air quality in the passenger compartment of an intercity bus is studied. A system used for the remotion of the contaminants from the compartment, based on an extraction duct, was projected using a simple, unidimensional flow model with capability to predict the air exchange rate as a function of the vehicle velocity. Some tests using tracer gan methods were performed in a real vehicle with the contaminant remotion system mounted, in order to validate the calculation model and evaluate the performances of the system. A good agreement between the predicted and the experimental results was verified and the obtained air exchange rate was quite reasonable when compared with the former situation, without extraction duct.

  11. Bladder distension as a cause of abdominal compartment syndrome

    International Nuclear Information System (INIS)

    Yasir, M.; Hoda, M.Q.

    2018-01-01

    Abdominal compartment syndrome (ACS) is increasingly identified in critically ill patient and its harmful effects are well documented. The disparity among the pressure, volume in abdominal cavity and its contents, results in ACS. The actual incidence of ACS is not known. However, it has been observed predominantly in patients with severe blunt and penetrating abdominal trauma, ruptured abdominal aortic aneurysms, retro- and intra-peritoneal hemorrhage, pneumoperitoneum, neoplasm, pancreatitis, ascites and multiple bone fracture. We present a case of 40-year female who underwent emergency cesarean section and developed abdominal compartment syndrome due to urinary bladder distension secondary to blockade of urinary catheter with blood clots. This is a very unusual cause of ACS. (author)

  12. ROCK1-directed basement membrane positioning coordinates epithelial tissue polarity.

    Science.gov (United States)

    Daley, William P; Gervais, Elise M; Centanni, Samuel W; Gulfo, Kathryn M; Nelson, Deirdre A; Larsen, Melinda

    2012-01-01

    The basement membrane is crucial for epithelial tissue organization and function. However, the mechanisms by which basement membrane is restricted to the basal periphery of epithelial tissues and the basement membrane-mediated signals that regulate coordinated tissue organization are not well defined. Here, we report that Rho kinase (ROCK) controls coordinated tissue organization by restricting basement membrane to the epithelial basal periphery in developing mouse submandibular salivary glands, and that ROCK inhibition results in accumulation of ectopic basement membrane throughout the epithelial compartment. ROCK-regulated restriction of PAR-1b (MARK2) localization in the outer basal epithelial cell layer is required for basement membrane positioning at the tissue periphery. PAR-1b is specifically required for basement membrane deposition, as inhibition of PAR-1b kinase activity prevents basement membrane deposition and disrupts overall tissue organization, and suppression of PAR-1b together with ROCK inhibition prevents interior accumulations of basement membrane. Conversely, ectopic overexpression of wild-type PAR-1b results in ectopic interior basement membrane deposition. Significantly, culture of salivary epithelial cells on exogenous basement membrane rescues epithelial organization in the presence of ROCK1 or PAR-1b inhibition, and this basement membrane-mediated rescue requires functional integrin β1 to maintain epithelial cell-cell adhesions. Taken together, these studies indicate that ROCK1/PAR-1b-dependent regulation of basement membrane placement is required for the coordination of tissue polarity and the elaboration of tissue structure in the developing submandibular salivary gland.

  13. 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...

  14. Intelligent Membranes: Dream or Reality?

    Directory of Open Access Journals (Sweden)

    Annarosa Gugliuzza

    2013-07-01

    Full Text Available Intelligent materials are claimed to overcome current drawbacks associated with the attainment of high standards of life, health, security and defense. Membrane-based sensors represent a category of smart systems capable of providing a large number of benefits to different markets of textiles, biomedicine, environment, chemistry, agriculture, architecture, transport and energy. Intelligent membranes can be characterized by superior sensitivity, broader dynamic range and highly sophisticated mechanisms of autorecovery. These prerogatives are regarded as the result of multi-compartment arrays, where complementary functions can be accommodated and well-integrated. Based on the mechanism of “sense to act”, stimuli-responsive membranes adapt themselves to surrounding environments, producing desired effects such as smart regulation of transport, wetting, transcription, hydrodynamics, separation, and chemical or energy conversion. Hopefully, the design of new smart devices easier to manufacture and assemble can be realized through the integration of sensing membranes with wireless networks, looking at the ambitious challenge to establish long-distance communications. Thus, the transfer of signals to collecting systems could allow continuous and real-time monitoring of data, events and/or processes.

  15. Bacterial assemblages differ between compartments within the coral holobiont

    Science.gov (United States)

    Sweet, M. J.; Croquer, A.; Bythell, J. C.

    2011-03-01

    It is widely accepted that corals are associated with a diverse and host species-specific microbiota, but how they are organized within their hosts remains poorly understood. Previous sampling techniques (blasted coral tissues, coral swabs and milked mucus) may preferentially sample from different compartments such as mucus, tissue and skeleton, or amalgamate them, making comparisons and generalizations between studies difficult. This study characterized bacterial communities of corals with minimal mechanical disruption and contamination from water, air and sediments from three compartments: surface mucus layer (SML), coral tissue and coral skeleton. A novel apparatus (the `snot sucker') was used to separate the SML from tissues and skeleton, and these three compartments were compared to swab samples and milked mucus along with adjacent environmental samples (water column and sediments). Bacterial 16S rRNA gene diversity was significantly different between the various coral compartments and environmental samples (PERMANOVA, F = 6.9, df = 8, P = 0.001), the only exceptions being the complete crushed coral samples and the coral skeleton, which were similar, because the skeleton represents a proportionally large volume and supports a relatively rich microflora. Milked mucus differed significantly from the SML collected with the `snot sucker' and was contaminated with zooxanthellae, suggesting that it may originate at least partially from the gastrovascular cavity rather than the tissue surface. A common method of sampling the SML, surface swabs, produced a bacterial community profile distinct from the SML sampled using our novel apparatus and also showed contamination from coral tissues. Our results indicate that microbial communities are spatially structured within the coral holobiont, and methods used to describe these need to be standardized to allow comparisons between studies.

  16. Hydrogen peroxide probes directed to different cellular compartments.

    OpenAIRE

    Mikalai Malinouski; You Zhou; Vsevolod V Belousov; Dolph L Hatfield; Vadim N Gladyshev

    2011-01-01

    Background Controlled generation and removal of hydrogen peroxide play important roles in cellular redox homeostasis and signaling. We used a hydrogen peroxide biosensor HyPer, targeted to different compartments, to examine these processes in mammalian cells. Principal Findings Reversible responses were observed to various redox perturbations and signaling events. HyPer expressed in HEK 293 cells was found to sense low micromolar levels of hydrogen peroxide. When targeted to various cellular ...

  17. Compartment syndrome after total knee arthroplasty: regarding a clinical case

    Directory of Open Access Journals (Sweden)

    Ana Alexandra da Costa Pinheiro

    2015-08-01

    Full Text Available ABSTRACT Although compartment syndrome is a rare complication of total knee arthroplasty, it is one of the most devastating complications. It is defined as a situation of increased pressure within a closed osteofascial space that impairs the circulation and the functioning of the tissues inside this space, thereby leading to ischemia and tissue dysfunction. Here, a clinical case of a patient who was followed up in orthopedic outpatient consultations due to right gonarthrosis is presented. The patient had a history of arthroscopic meniscectomy and presented knee flexion of 10° before the operation, which consisted of total arthroplasty of the right knee. The operation seemed to be free from intercurrences, but the patient evolved with compartment syndrome of the ipsilateral leg after the operation. Since compartment syndrome is a true surgical emergency, early recognition and treatment of this condition through fasciotomy is crucial in order to avoid amputation, limb dysfunction, kidney failure and death. However, it may be difficult to make the diagnosis and cases may not be recognized if the cause of compartment syndrome is unusual or if the patient is under epidural analgesia and/or peripheral nerve block, which thus camouflages the main warning sign, i.e. disproportional pain. In addition, edema of the limb that underwent the intervention is common after total knee arthroplasty operations. This study presents a review of the literature and signals that the possible rarity of cases is probably due to failure to recognize this condition in a timely manner and to placing these patients in other diagnostic groups that are less likely, such as neuropraxia caused by using a tourniquet or peripheral nerve injury.

  18. Elimination behavior of shelter dogs housed in double compartment kennels.

    Directory of Open Access Journals (Sweden)

    Denae Wagner

    Full Text Available For animals in confinement housing the housing structure has tremendous potential to impact well being. Dogs in animal shelters are often housed in one of two types of confinement housing - single kennels and rooms or double compartment kennels and rooms most often separated by a guillotine door. This study examines the effect of housing on the location of elimination behavior in dogs housed in double compartment kennels were the majority of the dogs were walked daily. One side of the kennel contained the food, water and bed and the other side was empty and available except during cleaning time. Location of urination and defecation was observed daily for 579 dogs housed in indoor double compartment kennels for a total of 4440 days of observation. There were 1856 days (41.9% when no elimination was noted in the kennel. Feces, urine or both were observed in the kennel on 2584 days (58.1%. When elimination occurred in the kennel the probability of fecal elimination on the opposite side of the bed/food/water was 72.5% (95% CI 69.05% to 75.69%. The probability of urination on the opposite side of the bed/food/water was 77.4% (95% CI 74.33% to 80.07%. This study demonstrates the strong preference of dogs to eliminate away from the area where they eat, drink and sleep. Double compartment housing not only allows this - it allows staff the ability to provide safe, efficient, humane daily care and confers the added benefits of reducing risks for disease transmission for the individual dog as well as the population.

  19. SACHET, Dynamic Fission Products Inventory in PWR Multiple Compartment System

    International Nuclear Information System (INIS)

    Kodaira, Hideki

    1990-01-01

    1 - Description of program or function: SACHET evaluates the dynamic fission product inventories in the multiple compartment system of pressurized water reactor (PWR) plants. 2 - Method of solution: SACHET utilizes a matrix of fission product core inventory which is previously calculated by the ORIGEN code. 3 - Restrictions on the complexity of the problem: Liquid wastes such as chemical waste and detergent waste are not included

  20. The pseudo-compartment method for coupling partial differential equation and compartment-based models of diffusion.

    Science.gov (United States)

    Yates, Christian A; Flegg, Mark B

    2015-05-06

    Spatial reaction-diffusion models have been employed to describe many emergent phenomena in biological systems. The modelling technique most commonly adopted in the literature implements systems of partial differential equations (PDEs), which assumes there are sufficient densities of particles that a continuum approximation is valid. However, owing to recent advances in computational power, the simulation and therefore postulation, of computationally intensive individual-based models has become a popular way to investigate the effects of noise in reaction-diffusion systems in which regions of low copy numbers exist. The specific stochastic models with which we shall be concerned in this manuscript are referred to as 'compartment-based' or 'on-lattice'. These models are characterized by a discretization of the computational domain into a grid/lattice of 'compartments'. Within each compartment, particles are assumed to be well mixed and are permitted to react with other particles within their compartment or to transfer between neighbouring compartments. Stochastic models provide accuracy, but at the cost of significant computational resources. For models that have regions of both low and high concentrations, it is often desirable, for reasons of efficiency, to employ coupled multi-scale modelling paradigms. In this work, we develop two hybrid algorithms in which a PDE in one region of the domain is coupled to a compartment-based model in the other. Rather than attempting to balance average fluxes, our algorithms answer a more fundamental question: 'how are individual particles transported between the vastly different model descriptions?' First, we present an algorithm derived by carefully redefining the continuous PDE concentration as a probability distribution. While this first algorithm shows very strong convergence to analytical solutions of test problems, it can be cumbersome to simulate. Our second algorithm is a simplified and more efficient implementation of

  1. Enrichment of boron 10

    International Nuclear Information System (INIS)

    Coutinho, C.M.M.; Rodrigues Filho, J.S.R.; Umeda, K.; Echternacht, M.V.

    1990-01-01

    A isotopic separation pilot plant with five ion exchange columns interconnected in series were designed and built in the IEN. The columns are charged with a strong anionic resin in its alkaline form. The boric acid solution is introduced in the separation columns until it reaches a absorbing zone length which is sufficient to obtain the desired boron-10 isotopic concentration. The boric acid absorbing zone movement is provided by the injection of a diluted hydrochloric acid solution, which replace the boric acid throughout the columns. The absorbing zone equilibrium length is proportional to its total length. The enriched boron-10 and the depleted boron are located in the final boundary and in the initial position of the absorbing zones, respectively. (author)

  2. Hypothyroid-induced acute compartment syndrome in all extremities.

    Science.gov (United States)

    Musielak, Matthew C; Chae, Jung Hee

    2016-12-20

    Acute compartment syndrome (ACS) is an uncommon complication of uncontrolled hypothyroidism. If unrecognized, this can lead to ischemia, necrosis and potential limb loss. A 49-year-old female presented with the sudden onset of bilateral lower and upper extremity swelling and pain. The lower extremity anterior compartments were painful and tense. The extensor surface of the upper extremities exhibited swelling and pain. Motor function was intact, however, limited due to pain. Bilateral lower extremity fasciotomies were performed. Postoperative Day 1, upper extremity motor function decreased significantly and paresthesias occurred. She therefore underwent bilateral forearm fasciotomies. The pathogenesis of hypothyroidism-induced compartment syndrome is unclear. Thyroid-stimulating hormone-induced fibroblast activation results in increased glycosaminoglycan deposition. The primary glycosaminoglycan in hypothyroid myxedematous changes is hyaluronic acid, which binds water causing edema. This increases vascular permeability, extravasation of proteins and impaired lymphatic drainage. These contribute to increased intra-compartmental pressure and subsequent ACS. Published by Oxford University Press and JSCR Publishing Ltd. All rights reserved. © The Author 2016.

  3. Perforated peptic ulcer associated with abdominal compartment syndrome.

    Science.gov (United States)

    Lynn, Jiun-Jen; Weng, Yi-Ming; Weng, Chia-Sui

    2008-11-01

    Abdominal compartment syndrome (ACS) is defined as an increased intra-abdominal pressure with adverse physiologic consequences. Abdominal compartment syndrome caused by perforated peptic ulcer is rare owing to early diagnosis and management. Delayed recognition of perforated peptic ulcer with pneumoperitoneum, bowel distension, and decreased abdominal wall compliance can make up a vicious circle and lead to ACS. We report a case of perforated peptic ulcer associated with ACS. A 74-year-old man with old stroke and dementia history was found to have distended abdomen, edema of bilateral legs, and cyanosis. Laboratory tests revealed deterioration of liver and kidney function. Abdominal compartment syndrome was suspected, and image study was arranged to find the cause. The study showed pneumoperitoneum, contrast stasis in heart with decreased caliber of vessels below the abdominal aortic level, and diffuse lymphedema at the abdominal walls. Emergent laparotomy was performed. Perforated peptic ulcer was noted and the gastrorrhaphy was done. The symptoms, and liver and kidney function improved right after emergent operation.

  4. Digital Microscopy Assessment of Angiogenesis in Different Breast Cancer Compartments

    Directory of Open Access Journals (Sweden)

    Anca Haisan

    2013-01-01

    Full Text Available Background/Aim. Tumour angiogenesis defined by microvessel density (MVD is generally accepted as a prognostic factor in breast cancer. However, due to variability of measurement systems and cutoffs, it is questionable to date whether it contributes to predictive outline. Our study aims to grade vascular heterogeneity by comparing clear-cut compartments: tumour associated stroma (TAS, tumour parenchyma, and tumour invasive front. Material and Methods. Computerized vessel area measurement was performed using a tissue cytometry system (TissueFAXS on slides originated from 50 patients with breast cancer. Vessels were marked using immunohistochemistry with CD34. Regions of interest were manually defined for each tumour compartment. Results. Tumour invasive front vascular endothelia area was 2.15 times higher than that in tumour parenchyma and 4.61 times higher than that in TAS (P<0.002. Worth to mention that the lymph node negative subgroup of patients show a slight but constant increase of vessel index in all examined compartments of breast tumour. Conclusion. Whole slide digital examination and region of interest (ROI analysis are a valuable tool in scoring angiogenesis markers and disclosing their prognostic capacity. Our study reveals compartments’ variability of vessel density inside the tumour and highlights the propensity of invasive front to associate an active process of angiogenesis with potential implications in adjuvant therapy.

  5. Thermal breeder fuel enrichment zoning

    International Nuclear Information System (INIS)

    Capossela, H.J.; Dwyer, J.R.; Luce, R.G.; McCoy, D.F.; Merriman, F.C.

    1992-01-01

    A method and apparatus for improving the performance of a thermal breeder reactor having regions of higher than average moderator concentration are disclosed. The fuel modules of the reactor core contain at least two different types of fuel elements, a high enrichment fuel element and a low enrichment fuel element. The two types of fuel elements are arranged in the fuel module with the low enrichment fuel elements located between the high moderator regions and the high enrichment fuel elements. Preferably, shim rods made of a fertile material are provided in selective regions for controlling the reactivity of the reactor by movement of the shim rods into and out of the reactor core. The moderation of neutrons adjacent the high enrichment fuel elements is preferably minimized as by reducing the spacing of the high enrichment fuel elements and/or using a moderator having a reduced moderating effect. 1 figure

  6. Advanced Neutron Source enrichment study

    International Nuclear Information System (INIS)

    Bari, R.A.; Ludewig, H.; Weeks, J.R.

    1996-01-01

    A study has been performed of the impact on performance of using low-enriched uranium (20% 235 U) or medium-enriched uranium (35% 235 U) as an alternative fuel for the Advanced Neutron Source, which was initially designed to use uranium enriched to 93% 235 U. Higher fuel densities and larger volume cores were evaluated at the lower enrichments in terms of impact on neutron flux, safety, safeguards, technical feasibility, and cost. The feasibility of fabricating uranium silicide fuel at increasing material density was specifically addressed by a panel of international experts on research reactor fuels. The most viable alternative designs for the reactor at lower enrichments were identified and discussed. Several sensitivity analyses were performed to gain an understanding of the performance of the reactor at parametric values of power, fuel density, core volume, and enrichment that were interpolations between the boundary values imposed on the study or extrapolations from known technology

  7. Membranous nephropathy

    Science.gov (United States)

    ... skin-lightening creams Systemic lupus erythematosus , rheumatoid arthritis, Graves disease, and other autoimmune disorders The disorder occurs at ... diagnosis. The following tests can help determine the cause of membranous nephropathy: Antinuclear antibodies test Anti-double- ...

  8. 75 FR 6092 - Special Conditions: Model C-27J Airplane; Class E Cargo Compartment Lavatory

    Science.gov (United States)

    2010-02-08

    ... envision that a lavatory would be installed inside a Class E cargo compartment. Lavatories, including the... envision that a lavatory would be installed in a Class E cargo compartment. Therefore, special conditions...

  9. Endocytosis of desmosomal plaques depends on intact actin filaments and leads to a nondegradative compartment

    DEFF Research Database (Denmark)

    Holm, Pernille K.; Hansen, Steen H.; Sandvig, Kirsten

    1993-01-01

    Cellebiologi, human epithelial cell line, growth inhibition, desmosomes, clathrin-independent endocytosis, cytoskeleton, nondegradative compartment......Cellebiologi, human epithelial cell line, growth inhibition, desmosomes, clathrin-independent endocytosis, cytoskeleton, nondegradative compartment...

  10. Enrichment plants. A survey of major new uranium enriching projects

    International Nuclear Information System (INIS)

    Kovan, D.

    1976-01-01

    The work enrichment situation is reported. The development of enrichment in the U.S. and in Europe is outlined. A brief description is given of the technology of separation by diffusion and by centrifugation and the advantages and disadvantages of the two processes are compared. Finally the supply and demand situation is briefly considered. (U.K.)

  11. Iron repletion relocalizes hephaestin to a proximal basolateral compartment in polarized MDCK and Caco2 cells

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung-Min [Department of Biological Sciences, University of Columbia, NY (United States); Department of Nutritional Science and Toxicology, University of California, Berkeley, CA (United States); Attieh, Zouhair K. [Department of Laboratory Science and Technology, American University of Science and Technology, Ashrafieh (Lebanon); Department of Nutritional Science and Toxicology, University of California, Berkeley, CA (United States); Son, Hee Sook [Department of Food Science and Human Nutrition, College of Human Ecology, Chonbuk National University (Korea, Republic of); Department of Nutritional Science and Toxicology, University of California, Berkeley, CA (United States); Chen, Huijun [Medical School, Nanjing University, Nanjing 210008, Jiangsu Province (China); Department of Nutritional Science and Toxicology, University of California, Berkeley, CA (United States); Bacouri-Haidar, Mhenia [Department of Biology, Faculty of Sciences (I), Lebanese University, Hadath (Lebanon); Department of Nutritional Science and Toxicology, University of California, Berkeley, CA (United States); Vulpe, Chris D., E-mail: vulpe@berkeley.edu [Department of Nutritional Science and Toxicology, University of California, Berkeley, CA (United States)

    2012-05-11

    Highlights: Black-Right-Pointing-Pointer Hephaestin localizes in the perinuclear space in non-polarized cells. Black-Right-Pointing-Pointer Hephaestin localizes in the perinuclear space in iron deficient and polarized cells. Black-Right-Pointing-Pointer Hephaestin with apical iron moves near to basolateral membrane of polarized cells. Black-Right-Pointing-Pointer Peri-basolateral location of hephaestin is accessible to the extracellular space. Black-Right-Pointing-Pointer Hephaestin is involved in iron mobilization from the intestine to circulation. -- Abstract: While intestinal cellular iron entry in vertebrates employs multiple routes including heme and non-heme routes, iron egress from these cells is exclusively channeled through the only known transporter, ferroportin. Reduced intestinal iron export in sex-linked anemia mice implicates hephaestin, a ferroxidase, in this process. Polarized cells are exposed to two distinct environments. Enterocytes contact the gut lumen via the apical surface of the cell, and through the basolateral surface, to the body. Previous studies indicate both local and systemic control of iron uptake. We hypothesized that differences in iron availability at the apical and/or basolateral surface may modulate iron uptake via cellular localization of hephaestin. We therefore characterized the localization of hephaestin in two models of polarized epithelial cell lines, MDCK and Caco2, with varying iron availability at the apical and basolateral surfaces. Our results indicate that hephaestin is expressed in a supra-nuclear compartment in non-polarized cells regardless of the iron status of the cells and in iron deficient and polarized cells. In polarized cells, we found that both apical (as FeSO{sub 4}) and basolateral iron (as the ratio of apo-transferrin to holo-transferrin) affect mobilization of hephaestin from the supra-nuclear compartment. We find that the presence of apical iron is essential for relocalization of hephaestin to a

  12. Analysis of Membrane Protein Topology in the Plant Secretory Pathway.

    Science.gov (United States)

    Guo, Jinya; Miao, Yansong; Cai, Yi

    2017-01-01

    Topology of membrane proteins provides important information for the understanding of protein function and intermolecular associations. Integrate membrane proteins are generally transported from endoplasmic reticulum (ER) to Golgi and downstream compartments in the plant secretory pathway. Here, we describe a simple method to study membrane protein topology along the plant secretory pathway by transiently coexpressing a fluorescent protein (XFP)-tagged membrane protein and an ER export inhibitor protein, ARF1 (T31N), in tobacco BY-2 protoplast. By fractionation, microsome isolation, and trypsin digestion, membrane protein topology could be easily detected by either direct confocal microscopy imaging or western-blot analysis using specific XFP antibodies. A similar strategy in determining membrane protein topology could be widely adopted and applied to protein analysis in a broad range of eukaryotic systems, including yeast cells and mammalian cells.

  13. Transport of Carbon Dioxide through a Biomimetic Membrane

    Directory of Open Access Journals (Sweden)

    Efstathios Matsaridis

    2011-01-01

    Full Text Available Biomimetic membranes (BMM based on polymer filters impregnated with lipids or their analogues are widely applied in numerous areas of physics, biology, and medicine. In this paper we report the design and testing of an electrochemical system, which allows the investigation of CO2 transport through natural membranes such as alveoli barrier membrane system and also can be applied for solid-state measurements. The experimental setup comprises a specially designed two-compartment cell with BMM connected with an electrochemical workstation placed in a Faraday cage, two PH meters, and a nondispersive infrared gas analyzer. We prove, experimentally, that the CO2 transport through the natural membranes under different conditions depends on pH and displays a similar behavior as natural membranes. The influence of different drugs on the CO2 transport process through such membranes is discussed.

  14. Numerical Study on Hydrogen Flow Behavior in Two Compartments with Different Connecting Pipes

    Directory of Open Access Journals (Sweden)

    HanChen Liu

    2017-01-01

    Full Text Available Hydrogen accumulation in the containment compartments under severe accidents would result in high concentration, which could lead to hydrogen deflagration or detonation. Therefore, getting detailed hydrogen flow and distribution is a key issue to arrange hydrogen removal equipment in the containment compartments. In this study, hydrogen flow behavior in local compartments has been investigated in two horizontal compartments. The analysis model is built by 3-dimensional CFD code in Cartesian coordinates based on the connection structure of the Advanced Pressurized Water Reactor (PWR compartments. It consists of two cylindrical vessels, representing the Steam Generator compartment (SG and Core Makeup Tank compartment (CMT. With standard k-ε turbulence model, the effects of the connecting pipe size and location on hydrogen concentration distribution are investigated. Results show that increasing the diameter of connection pipe (IP which is located at 800 mm from 150 mm to 300 mm facilitates hydrogen flow between compartments. Decreasing the length of IP which is located at 800 mm from 1000 mm to 500 mm can also facilitate hydrogen flow between compartments. Lower IP is in favor of hydrogen mixing with air in non-source compartment. Higher IP is helpful for hydrogen flow to the non-source term compartment from source term compartment.

  15. 46 CFR 171.017 - One and two compartment standards of flooding.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false One and two compartment standards of flooding. 171.017... standards of flooding. (a) One compartment standard of flooding. A vessel is designed to a one compartment standard of flooding if the margin line is not submerged when the total buoyancy between each set of two...

  16. Acute compartment syndrome after muscle rupture in a non-athlete.

    OpenAIRE

    Thennavan, A S; Funk, L; Volans, A P

    1999-01-01

    Acute compartment syndrome after muscle rupture, although rare, is a limb threatening condition, which warrants emergency treatment. The case of acute compartment syndrome secondary to a gastrocnemius muscle tear of the right lower leg, in a non-athlete is reported. To our knowledge, this is the only description of acute compartment syndrome due to muscle rupture in a non-athlete.

  17. Industrial aspects in uranium enrichment

    International Nuclear Information System (INIS)

    Mezin, M.

    1982-05-01

    Characteristics of isotope separation processes in operation and under development are discussed. These include the number of stages in series, the number of components, the component unit capacity and enery requirements. The implementation of an enrichment process and the question of an enrichment plant in Australia are also considered

  18. City model enrichment

    Science.gov (United States)

    Smart, Philip D.; Quinn, Jonathan A.; Jones, Christopher B.

    The combination of mobile communication technology with location and orientation aware digital cameras has introduced increasing interest in the exploitation of 3D city models for applications such as augmented reality and automated image captioning. The effectiveness of such applications is, at present, severely limited by the often poor quality of semantic annotation of the 3D models. In this paper, we show how freely available sources of georeferenced Web 2.0 information can be used for automated enrichment of 3D city models. Point referenced names of prominent buildings and landmarks mined from Wikipedia articles and from the OpenStreetMaps digital map and Geonames gazetteer have been matched to the 2D ground plan geometry of a 3D city model. In order to address the ambiguities that arise in the associations between these sources and the city model, we present procedures to merge potentially related buildings and implement fuzzy matching between reference points and building polygons. An experimental evaluation demonstrates the effectiveness of the presented methods.

  19. AEC determines uranium enrichment policy

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    The Advisory Committee on Uranium Enrichment of the Atomic Energy Commission (AEC) has submitted a report to AEC chairman concerning the promotion of the introduction of advanced material, high performance centrifuges to replace conventional metallic drum centrifuges, and the development of next generation advanced centrifuges. The report also called for the postponement until around 1997 of the decision whether the development should be continued or not on atomic vapor laser isotope separation (AVLIS) and molecular laser isotope separation (MLIS) processes, as well as the virtual freezing of the construction of a chemical process demonstration plant. The report was approved by the AEC chairman in August. The uranium enrichment service market in the world will continue to be characterized by oversupply. The domestic situation of uranium enrichment supply-demand trend, progress of the expansion of Rokkasho enrichment plant, the trend in the development of gas centrifuge process and the basic philosophy of commercializing domestic uranium enrichment are reported. (K.I.)

  20. Characterization of MRP RNA-protein interactions within the perinucleolar compartment.

    Science.gov (United States)

    Pollock, Callie; Daily, Kelly; Nguyen, Van Trung; Wang, Chen; Lewandowska, Marzena Anna; Bensaude, Olivier; Huang, Sui

    2011-03-15

    The perinucleolar compartment (PNC) forms in cancer cells and is highly enriched with a subset of polymerase III RNAs and RNA-binding proteins. Here we report that PNC components mitochondrial RNA-processing (MRP) RNA, pyrimidine tract-binding protein (PTB), and CUG-binding protein (CUGBP) interact in vivo, as demonstrated by coimmunoprecipitation and RNA pull-down experiments. Glycerol gradient analyses show that this complex is large and sediments at a different fraction from known MRP RNA-containing complexes, the MRP ribonucleoprotein ribozyme and human telomerase reverse transcriptase. Tethering PNC components to a LacO locus recruits other PNC components, further confirming the in vivo interactions. These interactions are present both in PNC-containing and -lacking cells. High-resolution localization analyses demonstrate that MRP RNA, CUGBP, and PTB colocalize at the PNC as a reticulated network, intertwining with newly synthesized RNA. Furthermore, green fluorescent protein (GFP)-PTB and GFP-CUGBP show a slower rate of fluorescence recovery after photobleaching at the PNC than in the nucleoplasm, illustrating the different molecular interaction of the complexes associated with the PNC. These findings support a working model in which the MRP RNA-protein complex becomes nucleated at the PNC in cancer cells and may play a role in gene expression regulation at the DNA locus that associates with the PNC.

  1. Characterization of MRP RNA–protein interactions within the perinucleolar compartment

    Science.gov (United States)

    Pollock, Callie; Daily, Kelly; Nguyen, Van Trung; Wang, Chen; Lewandowska, Marzena Anna; Bensaude, Olivier; Huang, Sui

    2011-01-01

    The perinucleolar compartment (PNC) forms in cancer cells and is highly enriched with a subset of polymerase III RNAs and RNA-binding proteins. Here we report that PNC components mitochondrial RNA–processing (MRP) RNA, pyrimidine tract–binding protein (PTB), and CUG-binding protein (CUGBP) interact in vivo, as demonstrated by coimmunoprecipitation and RNA pull-down experiments. Glycerol gradient analyses show that this complex is large and sediments at a different fraction from known MRP RNA–containing complexes, the MRP ribonucleoprotein ribozyme and human telomerase reverse transcriptase. Tethering PNC components to a LacO locus recruits other PNC components, further confirming the in vivo interactions. These interactions are present both in PNC-containing and -lacking cells. High-resolution localization analyses demonstrate that MRP RNA, CUGBP, and PTB colocalize at the PNC as a reticulated network, intertwining with newly synthesized RNA. Furthermore, green fluorescent protein (GFP)–PTB and GFP-CUGBP show a slower rate of fluorescence recovery after photobleaching at the PNC than in the nucleoplasm, illustrating the different molecular interaction of the complexes associated with the PNC. These findings support a working model in which the MRP RNA–protein complex becomes nucleated at the PNC in cancer cells and may play a role in gene expression regulation at the DNA locus that associates with the PNC. PMID:21233287

  2. Compartment-Specific Biosensors Reveal a Complementary Subcellular Distribution of Bioactive Furin and PC7

    Directory of Open Access Journals (Sweden)

    Pierpaolo Ginefra

    2018-02-01

    Full Text Available Furin trafficking, and that of related proprotein convertases (PCs, may regulate which substrates are accessible for endoproteolysis, but tools to directly test this hypothesis have been lacking. Here, we develop targeted biosensors that indicate Furin activity in endosomes is 10-fold less inhibited by decanoyl-RVKR-chloromethylketone and enriched >3-fold in endosomes compared to the trans-Golgi network (TGN. Endogenous PC7, which resists this inhibitor, was active in distinct vesicles. Only overexpressed PC7 activity reached the cell surface, endosomes, and the TGN. A PLC motif in the cytosolic tail of PC7 was dispensable for endosomal activity, but it was specifically required for TGN recycling and to rescue proActivin-A cleavage in Furin-depleted B16F1 melanoma cells. In sharp contrast, PC7 complemented Furin in cleaving Notch1 independently of PLC-mediated TGN access. Our study provides a proof in principle that compartment-specific biosensors can be used to gain insight into the regulation of PC trafficking and to map the tropism of PC-specific inhibitors.

  3. Lead contamination and transfer in urban environmental compartments analyzed by lead levels and isotopic compositions

    International Nuclear Information System (INIS)

    Hu, Xin; Sun, Yuanyuan; Ding, Zhuhong; Zhang, Yun; Wu, Jichun; Lian, Hongzhen; Wang, Tijian

    2014-01-01

    Lead levels and isotopic compositions in atmospheric particles (TSP and PM 2.5 ), street dust and surface soil collected from Nanjing, a mega city in China, were analyzed to investigate the contamination and the transfer of lead in urban environmental compartments. The lead contents in TSP and PM 2.5 are significantly higher than them in the surface soil and street dust (p  206 Pb/ 207 Pb vs. 208 Pb/ 206 Pb and 206 Pb/ 207 Pb vs. 1/Pb imply that the street dust and atmospheric particles (TSP and PM 2.5 ) have very similar lead sources. Coal emissions and smelting activities may be the important lead sources for street dust and atmospheric particles (TSP and PM 2.5 ), while the deposition of airborne lead is an important lead source for urban surface soil. - Highlights: • Lead levels and isotope ratios in atmospheric particles, street dust and surface soil. • Significant enrichment of lead in atmospheric particles was observed. • Street dust and atmospheric particles have similar lead sources. • Endmembers of soil lead differ from street dust and atmospheric particles. • Airborne lead poses the main risks to unban environmental quality. - Transfer of airborne particle bound lead into street dust and surface soil in unban environmental based on lead levels and isotopic compositions

  4. Lead contamination and transfer in urban environmental compartments analyzed by lead levels and isotopic compositions.

    Science.gov (United States)

    Hu, Xin; Sun, Yuanyuan; Ding, Zhuhong; Zhang, Yun; Wu, Jichun; Lian, Hongzhen; Wang, Tijian

    2014-04-01

    Lead levels and isotopic compositions in atmospheric particles (TSP and PM2.5), street dust and surface soil collected from Nanjing, a mega city in China, were analyzed to investigate the contamination and the transfer of lead in urban environmental compartments. The lead contents in TSP and PM2.5 are significantly higher than them in the surface soil and street dust (p lead to the major crustal elements (Al, Sr, Ti and Fe) indicates significant lead enrichment in atmospheric particles. The plots of (206)Pb/(207)Pb vs.(208)Pb/(206)Pb and (206)Pb/(207)Pb vs. 1/Pb imply that the street dust and atmospheric particles (TSP and PM2.5) have very similar lead sources. Coal emissions and smelting activities may be the important lead sources for street dust and atmospheric particles (TSP and PM2.5), while the deposition of airborne lead is an important lead source for urban surface soil. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. New generation enrichment monitoring technology for gas centrifuge enrichment plants

    International Nuclear Information System (INIS)

    Ianakiev, Kiril D.; Alexandrov, Boian S.; Boyer, Brian D.; Hill, Thomas R.; Macarthur, Duncan W.; Marks, Thomas; Moss, Calvin E.; Sheppard, Gregory A.; Swinhoe, Martyn T.

    2008-01-01

    The continuous enrichment monitor, developed and fielded in the 1990s by the International Atomic Energy Agency, provided a go-no-go capability to distinguish between UF 6 containing low enriched (approximately 4% 235 U) and highly enriched (above 20% 235 U) uranium. This instrument used the 22-keV line from a 109 Cd source as a transmission source to achieve a high sensitivity to the UF 6 gas absorption. The 1.27-yr half-life required that the source be periodically replaced and the instrument recalibrated. The instrument's functionality and accuracy were limited by the fact that measured gas density and gas pressure were treated as confidential facility information. The modern safeguarding of a gas centrifuge enrichment plant producing low-enriched UF 6 product aims toward a more quantitative flow and enrichment monitoring concept that sets new standards for accuracy stability, and confidence. An instrument must be accurate enough to detect the diversion of a significant quantity of material, have virtually zero false alarms, and protect the operator's proprietary process information. We discuss a new concept for advanced gas enrichment assay measurement technology. This design concept eliminates the need for the periodic replacement of a radioactive source as well as the need for maintenance by experts. Some initial experimental results will be presented.

  6. Complex Dynamic Development of Poliovirus Membranous Replication Complexes

    Science.gov (United States)

    Nair, Vinod; Hansen, Bryan T.; Hoyt, Forrest H.; Fischer, Elizabeth R.; Ehrenfeld, Ellie

    2012-01-01

    Replication of all positive-strand RNA viruses is intimately associated with membranes. Here we utilize electron tomography and other methods to investigate the remodeling of membranes in poliovirus-infected cells. We found that the viral replication structures previously described as “vesicles” are in fact convoluted, branching chambers with complex and dynamic morphology. They are likely to originate from cis-Golgi membranes and are represented during the early stages of infection by single-walled connecting and branching tubular compartments. These early viral organelles gradually transform into double-membrane structures by extension of membranous walls and/or collapsing of the luminal cavity of the single-membrane structures. As the double-membrane regions develop, they enclose cytoplasmic material. At this stage, a continuous membranous structure may have double- and single-walled membrane morphology at adjacent cross-sections. In the late stages of the replication cycle, the structures are represented mostly by double-membrane vesicles. Viral replication proteins, double-stranded RNA species, and actively replicating RNA are associated with both double- and single-membrane structures. However, the exponential phase of viral RNA synthesis occurs when single-membrane formations are predominant in the cell. It has been shown previously that replication complexes of some other positive-strand RNA viruses form on membrane invaginations, which result from negative membrane curvature. Our data show that the remodeling of cellular membranes in poliovirus-infected cells produces structures with positive curvature of membranes. Thus, it is likely that there is a fundamental divergence in the requirements for the supporting cellular membrane-shaping machinery among different groups of positive-strand RNA viruses. PMID:22072780

  7. Axionic membranes

    International Nuclear Information System (INIS)

    Aurilia, A.; Spallucci, E.

    1992-01-01

    A metal ring removed from a soap-water solution encloses a film of soap which can be mathematically described as a minimal surface having the ring as its only boundary. This is known to everybody. In this letter we suggest a relativistic extension of the above fluidodynamic system where the soap film is replaced by a Kalb-Ramand gauge potential B μν (x) and the ring by a closed string. The interaction between the B μν field and the string current excites a new configuration of the system consisting of a relativistic membrane bounded by the string. We call such a classical solution of the equation of motion an axionic membrane. As a dynamical system, the axionic membrane admits a Hamilton-Jacobi formulation which is an extension of the HJ theory of electromagnetic strings. (orig.)

  8. Recent advances in the management of abdominal compartment syndrome

    International Nuclear Information System (INIS)

    Saleem, T.B.; Ahmed, I.

    2004-01-01

    Abdominal compartment syndrome is a systemic syndrome involving derangement in cardiovascular hemodynamics, respiratory and renal function as a result of sustained increase in intra-abdominal pressure. This results in multi-organ failure requiring prompt action and treatment. Presentation can be acute, chronic and acute on chronic. Initial diagnosis is clinical, confirmed by measurement of urinary bladder pressure. Treatment is abdominal decompression by laparostomy and delayed abdominal closure. Awareness among the surgeons has increased because laparoscopy has resulted in determination of intra-abdominal pressure as a readily measurable quantity. They have been able to appreciate the benefit of abdominal decompression by performing repeated planned laparotomies for trauma. (author)

  9. Pericardial effusion and pericardial compartments after open heart surgery

    International Nuclear Information System (INIS)

    Duvernoy, O.; Larsson, S.G.; Persson, K.; Thuren, J.; Wikstroem, G.; Akademiska Sjukhuset, Uppsala; Akademiska Sjukhuset, Uppsala

    1990-01-01

    Thirty-three patients with pericardial effusion after open heart surgery were investigated with computed tomography (CT). Twelve of the 33 patients also underwent echocardiography prior to pericardiocentesis. The effusions were typed according to the results of the CT investigation. Because of postoperative adhesions, typical patterns of localized pericardial effusions were found in 16 patients. The localized compartments were seen on the right and left side of the heart and around the aorta and the pulmonary artery. CT was therefore shown to be of value for selecting the approach for drainage with catheter pericardiocentesis. (orig.)

  10. Modeling fires in adjacent ship compartments with computational fluid dynamics

    International Nuclear Information System (INIS)

    Wix, S.D.; Cole, J.K.; Koski, J.A.

    1998-01-01

    This paper presents an analysis of the thermal effects on radioactive (RAM) transportation pack ages with a fire in an adjacent compartment. An assumption for this analysis is that the adjacent hold fire is some sort of engine room fire. Computational fluid dynamics (CFD) analysis tools were used to perform the analysis in order to include convective heat transfer effects. The analysis results were compared to experimental data gathered in a series of tests on the United States Coast Guard ship Mayo Lykes located at Mobile, Alabama. (authors)

  11. Containment shells of reactor compartments at foreign NPPs

    International Nuclear Information System (INIS)

    Demidov, A.P.; Savchenko, V.A.

    1989-01-01

    The modern designes of containment shells (CS) of NPP reactor compartments is described. Much attention is paid to the PCS-3 project envisaging CS inclusion in the complex of NPP passive safety system. The PCS-3 system is developed in the USA for NPP with the improved PWR type reactor. The above system permits to cool the core quickly, to reduce steam pressure in CS down to a safe level and to prevent the discharge of radioactive products in the atmosphere in the case of accidents, even very serious, caused by loss of coolant and core dryout

  12. A two-compartment exposure device for foliar uptake study

    International Nuclear Information System (INIS)

    Zuo, Q.; Lin, H.; Zhang, X.L.; Li, Q.L.; Liu, S.Z.; Tao, S.

    2006-01-01

    An airtight two-chamber exposure devise was designed for investigating foliar uptake of polycyclic aromatic hydrocarbons (PAHs) by plants. The upper and the bottom chambers of the device were air-tightly separated by an aluminum foil and the plant aerial tissues and roots were exposed in the two chambers, respectively. The device was tested using maize exposed to several PAH species. Positive correlations between air and aerial tissue concentrations of the exposed PAH species were revealed. PAHs spiking in the culture solution had no influence on the leaf concentrations. -- A two-compartment gastight exposure device was developed for investigation of foliar uptake of PAHs by plants

  13. Arthroscopic meniscectomy in medial compartment osteoarthritis of the knee

    International Nuclear Information System (INIS)

    Noguchi, Joji; Shimoyama, Gishichiro; Shinozaki, Toshiro; Nagata, Kensei

    2007-01-01

    The purpose of this research is to evaluate the results of arthroscopic meniscectomy in medial compartment osteoarthritis of the knee. The operation was performed on 25 knee joints (8 male, 17 female) with the mean age of 67 years. The mean period of follow-up was 19 months. Clinical results were more or less excellent, but radiological assessment suggested slight osteoarthritic changes. In addition, two cases progressed to subchondral bone collapse. Of 12 cases which had no bone marrow edema on MRI before surgery, six (50%) cases showed it at follow-up. These findings suggest a possible relationship between arthroscopic meniscectomy and later appearance of osteonecrosis in some cases. (author)

  14. Electrochemical synthesis of gold nanorods in track-etched polycarbonate membrane using removable mercury cathode

    International Nuclear Information System (INIS)

    Sharma, Manoj K.; Ambolikar, Arvind S.; Aggarwal, Suresh K.

    2012-01-01

    The electrochemical template synthesis of gold nanorods within the cylindrical pores of track-etched polycarbonate (PC) membrane using a removable mercury cathode is reported. The novelty of this new approach is that it eliminates the requirement of coating an approximately 500 nm–1 μm-thick metallic layer, as conducting substrate, onto one surface of the insulating template membrane by the sputter deposition technique. A two-compartment electrochemical cell was designed and used for this work. The PC membrane was placed between the two compartments separating the aqueous solution of HAuCl 4 from mercury. Mercury, filled in one of the compartments, is in contact with one surface of the membrane (similar to sputter-deposited metallic layer) and serves as the conducting substrate/cathode for the electrochemical deposition of gold in the nanopores of track-etched PC membrane. Once the electrodeposition is completed, the mercury and the HAuCl 4 solution are removed from the compartments, and a malleable track-etched PC membrane embedded with free-standing gold nanorods is obtained. The ensemble of the metal nanorods grown in the template membrane is not attached to any conducting substrate, and gold nanorods can be freed from the template membrane after the dissolution. The Au-deposited PC membrane and free-standing Au nanorods were characterized by EDXRF, XRD, UV–Visible spectroscopy, AFM, and FEG-TEM. The EDXRF and XRD studies confirmed the deposition of the face-centered cubic phase of Au in the pores of the PC membrane. The TEM studies showed the formation of a cigar-shaped gold nanorod in the cylindrical pores of the PC membrane. The diameter of gold nanorods ranges from 100 to 200 nm. The new approach is simple, cost-effective, and saves time.

  15. Metamaterial membranes

    International Nuclear Information System (INIS)

    Restrepo-Flórez, Juan Manuel; Maldovan, Martin

    2017-01-01

    We introduce a new class of metamaterial device to achieve separation of compounds by using coordinate transformations and metamaterial theory. By rationally designing the spatial anisotropy for mass diffusion, we simultaneously concentrate different compounds in different spatial locations, leading to separation of mixtures across a metamaterial membrane. The separation of mixtures into their constituent compounds is critically important in biophysics, biomedical, and chemical applications. We present a practical case where a mixture of oxygen and nitrogen diffusing through a polymeric planar matrix is separated. This work opens doors to new paradigms in membrane separations via coordinate transformations and metamaterials by introducing novel properties and unconventional mass diffusion phenomena. (paper)

  16. Hydrogen-enriched fuels

    Energy Technology Data Exchange (ETDEWEB)

    Roser, R. [NRG Technologies, Inc., Reno, NV (United States)

    1998-08-01

    NRG Technologies, Inc. is attempting to develop hardware and infrastructure that will allow mixtures of hydrogen and conventional fuels to become viable alternatives to conventional fuels alone. This commercialization can be successful if the authors are able to achieve exhaust emission levels of less than 0.03 g/kw-hr NOx and CO; and 0.15 g/kw-hr NMHC at full engine power without the use of exhaust catalysts. The major barriers to achieving these goals are that the lean burn regimes required to meet exhaust emissions goals reduce engine output substantially and tend to exhibit higher-than-normal total hydrocarbon emissions. Also, hydrogen addition to conventional fuels increases fuel cost, and reduces both vehicle range and engine output power. Maintaining low emissions during transient driving cycles has not been demonstrated. A three year test plan has been developed to perform the investigations into the issues described above. During this initial year of funding research has progressed in the following areas: (a) a cost effective single-cylinder research platform was constructed; (b) exhaust gas speciation was performed to characterize the nature of hydrocarbon emissions from hydrogen-enriched natural gas fuels; (c) three H{sub 2}/CH{sub 4} fuel compositions were analyzed using spark timing and equivalence ratio sweeping procedures and finally; (d) a full size pick-up truck platform was converted to run on HCNG fuels. The testing performed in year one of the three year plan represents a baseline from which to assess options for overcoming the stated barriers to success.

  17. Dynamic shaping of cellular membranes by phospholipids and membrane-deforming proteins.

    Science.gov (United States)

    Suetsugu, Shiro; Kurisu, Shusaku; Takenawa, Tadaomi

    2014-10-01

    All cellular compartments are separated from the external environment by a membrane, which consists of a lipid bilayer. Subcellular structures, including clathrin-coated pits, caveolae, filopodia, lamellipodia, podosomes, and other intracellular membrane systems, are molded into their specific submicron-scale shapes through various mechanisms. Cells construct their micro-structures on plasma membrane and execute vital functions for life, such as cell migration, cell division, endocytosis, exocytosis, and cytoskeletal regulation. The plasma membrane, rich in anionic phospholipids, utilizes the electrostatic nature of the lipids, specifically the phosphoinositides, to form interactions with cytosolic proteins. These cytosolic proteins have three modes of interaction: 1) electrostatic interaction through unstructured polycationic regions, 2) through structured phosphoinositide-specific binding domains, and 3) through structured domains that bind the membrane without specificity for particular phospholipid. Among the structured domains, there are several that have membrane-deforming activity, which is essential for the formation of concave or convex membrane curvature. These domains include the amphipathic helix, which deforms the membrane by hemi-insertion of the helix with both hydrophobic and electrostatic interactions, and/or the BAR domain superfamily, known to use their positively charged, curved structural surface to deform membranes. Below the membrane, actin filaments support the micro-structures through interactions with several BAR proteins as well as other scaffold proteins, resulting in outward and inward membrane micro-structure formation. Here, we describe the characteristics of phospholipids, and the mechanisms utilized by phosphoinositides to regulate cellular events. We then summarize the precise mechanisms underlying the construction of membrane micro-structures and their involvements in physiological and pathological processes. Copyright © 2014 the

  18. Long-term ongoing impact of arsenic contamination on the environmental compartments of a former mining-metallurgy area.

    Science.gov (United States)

    González-Fernández, B; Rodríguez-Valdés, E; Boente, C; Menéndez-Casares, E; Fernández-Braña, A; Gallego, J R

    2018-01-01

    Arsenic and mercury are potentially toxic elements of concern for soil, surficial and ground waters, and sediments. In this work various geochemical and hydrogeological tools were used to study a paradigmatic case of the combined effects of the abandonment of Hg- and As-rich waste on these environmental compartments. Continuous weathering of over 40years has promoted As and Hg soil pollution (thousands of ppm) in the surroundings of a former Hg mining-metallurgy site and affected the water quality of a nearby river and shallow groundwater. In particular, the high availability of As both in soils and waste was identified as one of the main determinants of contaminant distribution, whereas the impact of Hg was found to be minor, which is explained by lower mobility. Furthermore, potential additional sources of pollution (coal mining, high natural backgrounds, etc.) discharging into the study river were revealed less significant than the contaminants generated in the Hg-mining area. The transport and deposition of pollutants within the water cycle has also affected several kilometres downstream of the release areas and the chemistry of stream sediments. Overall, the environmental compartments studies held considerable concentrations of Hg and As, as remarkably revealed by the average contaminant load released in the river (several tons of As per year) and the accumulation of toxic elements in sediments (enrichment factors of As and Hg above 35). Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Delayed Presentation of Gluteal Compartment Syndrome: The Argument for Fasciotomy

    Directory of Open Access Journals (Sweden)

    John E. Lawrence

    2016-01-01

    Full Text Available A male patient in his fifties presented to his local hospital with numbness and weakness of the right leg which left him unable to mobilise. He reported injecting heroin the previous morning. Following an initial diagnosis of acute limb ischaemia the patient was transferred to a tertiary centre where Computed Tomography Angiography was reported as normal. Detailed neurological examination revealed weakness in hip flexion and extension (1/5 on the Medical Research Council scale with complete paralysis of muscle groups distal to this. Sensation to pinprick and light touch was globally reduced. Blood tests revealed acute kidney injury with raised creatinine kinase and the patient was treated for rhabdomyolysis. Orthopaedic referral was made the following day and a diagnosis of gluteal compartment syndrome (GCS was made. Emergency fasciotomy was performed 56 hours after the onset of symptoms. There was immediate neurological improvement following decompression and the patient was rehabilitated with complete nerve recovery and function at eight-week follow-up. This is the first documented case of full functional recovery following a delayed presentation of GCS with sciatic nerve palsy. We discuss the arguments for and against fasciotomy in cases of compartment syndrome with significant delay in presentation or diagnosis.

  20. Shock absorber system for nuclear reactor ice condenser compartment

    International Nuclear Information System (INIS)

    Meier, J.F.; Rudd, G.E.; Pradhan, A.V.; George, J.A.; Lippincott, H.W.; Sutherland, J.D.

    1979-01-01

    A shock absorber system was designed to absorb the energy imparted to doors in a nuclear reactor ice condenser compartment as they swing rapidly to an open position. Each shock absorber which is installed on a wall adjacent to each door is large and must absorb up to about 40,000 foot pounds of energy. The basic shock absorber component comprises foam enclosed in a synthetic fabric bag having a volume about twice the foam volume. A stainless steel knitted mesh bag of the same volume as the fabric bag, contains the fabric bag and its enclosed foam. To protect the foam and bags during construction activities at the reactor site and from the shearing action of the doors, a protective sheet metal cover is installed over the shock absorber ends and the surface to be contacted by the moving door. With the above shock absorber mounted on a wall behind each door, as the door is forcibly opened by steam pressure and air resulting from a pipe break in the reactor compartment, it swings at a high velocity into contact with the shock absorber, crushes the foam and forces it into the fabric bag excess material thus containing the foam fragmented particles, and minimizes build-up of pressure in the bag as a result of the applied compressive force

  1. Identifiability Results for Several Classes of Linear Compartment Models.

    Science.gov (United States)

    Meshkat, Nicolette; Sullivant, Seth; Eisenberg, Marisa

    2015-08-01

    Identifiability concerns finding which unknown parameters of a model can be estimated, uniquely or otherwise, from given input-output data. If some subset of the parameters of a model cannot be determined given input-output data, then we say the model is unidentifiable. In this work, we study linear compartment models, which are a class of biological models commonly used in pharmacokinetics, physiology, and ecology. In past work, we used commutative algebra and graph theory to identify a class of linear compartment models that we call identifiable cycle models, which are unidentifiable but have the simplest possible identifiable functions (so-called monomial cycles). Here we show how to modify identifiable cycle models by adding inputs, adding outputs, or removing leaks, in such a way that we obtain an identifiable model. We also prove a constructive result on how to combine identifiable models, each corresponding to strongly connected graphs, into a larger identifiable model. We apply these theoretical results to several real-world biological models from physiology, cell biology, and ecology.

  2. A multiple-compartment model for biokinetics studies in plants

    International Nuclear Information System (INIS)

    Garcia, Fermin; Pietrobron, Flavio; Fonseca, Agnes M.F.; Mol, Anderson W.; Rodriguez, Oscar; Guzman, Fernando

    2001-01-01

    In the present work is used the system of linear equations based in the general Assimakopoulos's GMCM model , for the development of a new method that will determine the flow's parameters and transfer coefficients in plants. The need of mathematical models to quantify the penetration of a trace substance in animals and plants, has often been stressed in the literature. Usually, in radiological environment studies, it is used the mean value of contaminant concentrations on whole or edible part plant body, without taking in account vegetable physiology regularities. In this work concepts and mathematical formulation of a Vegetable Multi-compartment Model (VMCM), taking into account the plant's physiology regularities is presented. The model based in general ideas of the GMCM , and statistical Square Minimum Method STATFLUX is proposed to use in inverse sense: the experimental time dependence of concentration in each compartment, should be input, and the parameters should be determined from this data in a statistical approach. The case of Uranium metabolism is discussed. (author)

  3. Compartment Syndrome as a Result of Systemic Capillary Leak Syndrome

    Directory of Open Access Journals (Sweden)

    Kwadwo Kyeremanteng

    2016-01-01

    Full Text Available Objective. To describe a single case of Systemic Capillary Leak Syndrome (SCLS with a rare complication of compartment syndrome. Patient. Our patient is a 57-year-old male, referred to our hospital due to polycythemia (hemoglobin (Hgb of 220 g/L, hypotension, acute renal failure, and bilateral calf pain. Measurements and Main Results. The patient required bilateral forearm, thigh, and calf fasciotomies during his ICU stay and continuous renal replacement therapy was instituted following onset of acute renal failure and oliguria. Ongoing hemodynamic (Norepinephrine and Milrinone infusion and respiratory (ventilator support in the ICU was provided until resolution of intravascular fluid extravasation. Conclusions. SCLS is an extremely rare disorder characterized by unexplained episodic capillary hyperpermeability, which causes shift of volume and protein from the intravascular space to the interstitial space. Patients present with significant hypotension, hemoconcentration, hypovolemia, and oliguria. Severe edema results from leakage of fluid and proteins into tissue. The most important part of treatment is maintaining stable hemodynamics, ruling out other causes of shock and diligent monitoring for complications. Awareness of the clinical syndrome with the rare complication of compartment syndrome may help guide investigations and diagnoses of these critically ill patients.

  4. Improved hydrogen combustion model for multi-compartment analysis

    International Nuclear Information System (INIS)

    Ogino, Masao; Hashimoto, Takashi

    2000-01-01

    NUPEC has been improving a hydrogen combustion model in MELCOR code for severe accident analysis. In the proposed combustion model, the flame velocity in a node was predicted using six different flame front shapes of fireball, prism, bubble, spherical jet, plane jet, and parallelepiped. A verification study of the proposed model was carried out using the NUPEC large-scale combustion test results following the previous work in which the GRS/Battelle multi-compartment combustion test results had been used. The selected test cases for the study were the premixed test and the scenario-oriented test which simulated the severe accident sequences of an actual plant. The improved MELCOR code replaced by the proposed model could predict sufficiently both results of the premixed test and the scenario-oriented test of NUPEC large-scale test. The improved MELCOR code was confirmed to simulate the combustion behavior in the multi-compartment containment vessel during a severe accident with acceptable degree of accuracy. Application of the new model to the LWR severe accident analysis will be continued. (author)

  5. Atraumatic medial collateral ligament oedema in medial compartment knee osteoarthritis

    International Nuclear Information System (INIS)

    Bergin, D.; Keogh, C.; O'Connell, M.; Zoga, A.; Rowe, D.; Shah, B.; Eustace, S.

    2002-01-01

    Objective: To describe and determine the prevalence of atraumatic medial collateral oedema identified in patients with medial compartment osteoarthritis. Design and patients: Sixty patients, 30 patients with medial compartment knee osteoarthritis (Kellgren and Lawrence grade 2 to 4) and 30 age-matched patients with atraumatic knee pain without osteoarthritis, referred for MR imaging over a 2 year period were included in the study. In each case, severity of osteoarthritis was recorded on radiographs and correlated with the presence or absence of medial collateral ligament oedema at MR imaging. Results: Medial collateral oedema was identified in 27 of the 30 patients with osteoarthritis, of whom 14 had grade 1 oedema and 13 had grade 2 oedema compared with the presence of medial collateral ligament oedema (grade 1) in only two of the 30 control patients without osteoarthritis (P<<0.0001). Conclusion: Medial collateral oedema is common in patients with osteoarthritis in the absence of trauma. When identified, medial collateral ligament oedema should be considered to be a feature of osteoarthritis and should not be incorrectly attributed to an acute traumatic injury. (orig.)

  6. High enrichment to low enrichment core's conversion. Technical securities

    International Nuclear Information System (INIS)

    Abbate, P.; Madariaga, M.R.

    1990-01-01

    This work presents the fulfillment of the technical securities subscribed by INVAP S.E. for the conversion of a high enriched uranium core. The reactor (of 5 thermal Mw), built in the 50's and 60's, is of the 'swimming pool' type, with light water and fuel elements of the curve plates MTR type, enriched at 93.15 %. These are neutronic and thermohydraulic securities. (Author) [es

  7. Chelating polymeric membranes

    KAUST Repository

    Peinemann, Klaus-Viktor; Villalobos Vazquez de la Parra, Luis Francisco; Hilke, Roland

    2015-01-01

    microporous chelating polymeric membrane. Embodiments include, but are not limited to, microporous chelating polymeric membranes, device comprising the membranes, and methods of using and making the same.

  8. Safety of uranium enrichment plant

    International Nuclear Information System (INIS)

    Yonekawa, Shigeru; Morikami, Yoshio; Morita, Minoru; Takahashi, Tsukasa; Tokuyasu, Takashi.

    1991-01-01

    With respect to safety evaluation of the gas centrifuge enrichment facility, several characteristic problems are described as follows. Criticality safety in the cascade equipments can be obtained to maintain the enrichment of UF 6 below 5 %. External radiation dose equivalent rate of the 30B cylinder is low enough, the shield is not necessary. Penetration ratio of the two-stage HEPA filters for UF 6 aerosol is estimated at 10 -9 . From the experimental investigation, vacuum tightness is not damaged by destruction of gas centrifuge rotor. Carbon steel can be used for uranium enrichment equipments under the condition below 100degC. (author)

  9. Environmental enrichment for aquatic animals.

    Science.gov (United States)

    Corcoran, Mike

    2015-05-01

    Aquatic animals are the most popular pets in the United States based on the number of owned pets. They are popular display animals and are increasingly used in research settings. Enrichment of captive animals is an important element of zoo and laboratory medicine. The importance of enrichment for aquatic animals has been slower in implementation. For a long time, there was debate over whether or not fish were able to experience pain or form long-term memories. As that debate has reduced and the consciousness of more aquatic animals is accepted, the need to discuss enrichment for these animals has increased. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. World enrichment requirements to 2005

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    The primary enrichment suppliers-Eurodif, Techsnabexport, Urenco, and the US DOE - are positioning themselves to take advantage of the post - 1995 market. Overall, unfilled requirements represent about 40 percent of world requirements in the year 2000. The USA will be the primary market, as US utilities' unfilled enrichment requirements account for over 60 percent of the world's total unfilled requirements. The enrichment market is moving toward more global competition, as each supplier tries to maintain its current regional market base and then to capture additional market share in other regions

  11. Durability of PEM Fuel Cell Membranes

    Science.gov (United States)

    Huang, Xinyu; Reifsnider, Ken

    Durability is still a critical limiting factor for the commercialization of polymer electrolyte membrane (PEM) fuel cells, a leading energy conversion technology for powering future hydrogen fueled automobiles, backup power systems (e.g., for base transceiver station of cellular networks), portable electronic devices, etc. Ionic conducting polymer (ionomer) electrolyte membranes are the critical enabling materials for the PEM fuel cells. They are also widely used as the central functional elements in hydrogen generation (e.g., electrolyzers), membrane cell for chlor-alkali production, etc. A perfluorosulfonic acid (PFSA) polymer with the trade name Nafion® developed by DuPont™ is the most widely used PEM in chlor-alkali cells and PEM fuel cells. Similar PFSA membranes have been developed by Dow Chemical, Asahi Glass, and lately Solvay Solexis. Frequently, such membranes serve the dual function of reactant separation and selective ionic conduction between two otherwise separate compartments. For some applications, the compromise of the "separation" function via the degradation and mechanical failure of the electrolyte membrane can be the life-limiting factor; this is particularly the case for PEM in hydrogen/oxygen fuel cells.

  12. Centar's gas centrifuge enrichment project

    International Nuclear Information System (INIS)

    Abajian, V.V.; Fishman, A.M.

    1976-01-01

    Plans for the building and operating of Centar Associates gas centrifuge uranium enrichment plant are described. Operating costs and machine manufacture are considered. Commitments with the utilities are summarised. (U.K.)

  13. Extraosseus enrichments in bone scintigraphy

    International Nuclear Information System (INIS)

    Jochens, R.; Schumacher, T.; Amthauer, H.; Wolter, M.; Stock, W.; Stroszczynski, C.; Moersler, J.P.; Eichstaedt, H.

    1996-01-01

    Extraosseus enrichments are common findings in bone scintigraphy. Main causes are artifacts by skin or cloth contamination, paravenous and subcutaneous injection. Physical examination, removal of cloths, skin cleaning or further images in differing projections lead to the correct diagnosis artefact or extraosseous enrichments. Further on, extraosseous enrichments are seen in physiological variants. In different diseases extraosseous enrichments are common, especially in urinary tract, liver and extremities. Further diagnostics, e.g. conventional radiologic procedures, sonography and CT scans, have to be performed. In individual cases side results in bone scintigraphy lead to formerly unknown diagnosis, further diagnostic procedure is influenced decisively. Own cases show for example a cerebral apoplectic insult, formerly unknown liver metastasis or metastasis in extraosseous Ewings's sarcoma. (orig.) [de

  14. Influence of the fuel and dosage on the performance of double-compartment microbial fuel cells.

    Science.gov (United States)

    Asensio, Y; Fernandez-Marchante, C M; Lobato, J; Cañizares, P; Rodrigo, M A

    2016-08-01

    This manuscript focuses on the evaluation of the use of different types and dosages of fuels in the performance of double-compartment microbial fuel cell equipped with carbon felt electrodes and cationic membrane. Five types of fuels (ethanol, glycerol, acetate, propionate and fructose) have been tested for the same organic load (5,000 mg L(-1) measured as COD) and for one of them (acetate), the range of dosages between 500 and 20,000 mg L(-1) of COD was also studied. Results demonstrate that production of electricity depends strongly on the fuel used. Carboxylic acids are much more efficient than alcohols or fructose for the same organic load and within the range 500-5,000 mg L(-1) of acetate the production of electricity increases linearly with the amount of acetate fed but over these concentrations a change in the population composition may explain a worse performance. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Fatty acid profiles from the plasma membrane and detergent resistant membranes of two plant species.

    Science.gov (United States)

    Carmona-Salazar, Laura; El Hafidi, Mohammed; Gutiérrez-Nájera, Nora; Noyola-Martínez, Liliana; González-Solís, Ariadna; Gavilanes-Ruíz, Marina

    2015-01-01

    It is essential to establish the composition of the plant plasma membrane in order to understand its organization and behavior under continually changing environments. Knowledge of the lipid phase, in particular the fatty acid (FA) complex repertoire, is important since FAs determine many of the physical-chemical membrane properties. FAs are constituents of the membrane glycerolipid and sphingolipid backbones and can also be linked to some sterols. In addition, FAs are components of complex lipids that can constitute membrane micro-domains, and the use of detergent-resistant membranes is a common approach to study their composition. The diversity and cellular allocation of the membrane lipids containing FAs are very diverse and the approaches to analyze them provide only general information. In this work, a detailed FA analysis was performed using highly purified plasma membranes from bean leaves and germinating maize embryos and their respective detergent-resistant membrane preparations. The analyses showed the presence of a significant amount of very long chain FAs (containing 28C, 30C and 32C), in both plasma membrane preparations from bean and maize, that have not been previously reported. Herein is demonstrated that a significant enrichment of very long chain saturated FAs and saturated FAs can occur in detergent-resistant membrane preparations, as compared to the plasma membranes from both plant species. Considering that a thorough analysis of FAs is rarely performed in purified plasma membranes and detergent-resistant membranes, this work provides qualitative and quantitative evidence on the contributions of the length and saturation of FAs to the organization of the plant plasma membrane and detergent-resistant membranes. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Uranium enrichment: an evolving market

    International Nuclear Information System (INIS)

    Longenecker, J.; Witzel, R.

    1997-01-01

    With over half of the world uranium enrichment market uncommitted to any supplier early in the next century, competition is certain to be fierce. In the meantime the outlood remains unclear, with the market dominated by a number of developments -privatisation of the United States Enrichment Corp (USEC), increasing availability of Russian and US military inventories, the deployment of advanced technology and the closure of nuclear power plants due to deregulation. (author)

  17. Unjust enrichment in business law

    OpenAIRE

    Vydrová, Zuzana

    2016-01-01

    This thesis analyses the concept of unjust enrichment under the business law. First of all the thesis explains the term of business law. Business law is a complex of legal rules concerning the contractual relationships between entrepreneurs arising from their business activities. Business law is a comprehensive field of law which extends into many other fields of law, both private and public law. Equally the regulation of unjust enrichment within the business law expands into many other laws ...

  18. Estimation of Water Footprint Compartments in National Wheat Production

    Directory of Open Access Journals (Sweden)

    B. Ababaei

    2016-09-01

    Full Text Available Introduction: Water use and pollution have raised to a critical level in many compartments of the world. If humankind is to meet the challenges over the coming fifty years, the agricultural share of water use has to be substantially reduced. In this study, a modern yet simple approach has been proposed through the introduction concept ‘Water Footprint’ (WF. This concept can be used to study the connection between each product and the water allocation to produce that product. This research estimates the green, blue and gray WF of wheat in Iran. Also a new WF compartment (white is used that is related about irrigation water loss. Materials and Methods: The national green (Effective precipitation, blue (Net irrigation requirement, gray (For diluting chemical fertilizers and white (Irrigation water losses water footprints (WF of wheat production were estimated for fifteen major wheat producing provinces of Iran. Evapotranspiration, irrigation requirement, gross irrigation requirement and effective rainfall were got using the AGWAT model. Yields of irrigated and rain-fed lands of each province were got from Iran Agricultural-Jihad Ministry. Another compartment of the wheat production WF is related about the volume of water required to assimilate the fertilizers leached in runoff (gray WF. Moreover, a new concept of white water footprint was proposed here and represents irrigation water losses, which was neglected in the original calculation framework. Finally, the national WF compartments of wheat production were estimated by taking the average of each compartment over all the provinces weighted by the share of each province in total wheat production of the selected provinces. Results and Discussion: In 2006-2012, more than 67% of the national wheat production was irrigated and 32.3% were rain-fed, on average, while 37.9% of the total wheat-cultivated lands were irrigated and 62.1% was rain-fed from more than 6,568 -ha. The total national WF of

  19. Mixing of radiolytic hydrogen generated within a containment compartment following a LOCA

    International Nuclear Information System (INIS)

    Willcutt, G.J.E. Jr.; Gido, R.G.

    1978-07-01

    The objective of this work was to determine hydrogen concentration variations with position and time in a closed containment compartment with radiolytic hydrogen generation in the water on the compartment floor following a Loss-of-Coolant-Accident (LOCA). One application is to determine the potential difference between the compartment maximum hydrogen concentration and a hydrogen detector reading, due to the detector location. Three possible mechanisms for hydrogen transport in the compartment were investigated: (1) molecular diffusion, (2) possible bubble formation and motion, and (3) natural convection flows. A base case cubic compartment with 6.55-m (21.5-ft) height was analyzed. Parameter studies were used to determine the sensitivity of results to compartment size, hydrogen generation rates, diffusion coefficients, and the temperature difference between the floor and the ceiling and walls of the compartment. Diffusion modeling indicates that if no other mixing mechanism is present for the base case, the maximum hydrogen volume percent (vol percent) concentration difference between the compartment floor and ceiling will be 4.8 percent. It will be 24.5 days before the maximum concentration difference is less than 0.5 percent. Bubbles do not appear to be a potential source of hydrogen pocketing in a containment compartment. Compartment natural convection circulation rates for a 2.8 K (5 0 F) temperature difference between the floor and the ceiling and walls are estimated to be at least the equivalent of 1 compartment volume per hour and probably in the range of 4 to 9 compartment volumes per hour. Related natural convection studies indicate there will be turbulent mixing in the compartment for a 2.8 K (5 0 F) temperature difference between the floor and the ceiling and walls

  20. Matrix metalloproteinase-9 expression in the nuclear compartment of neurons and glial cells in aging and stroke.

    Science.gov (United States)

    Pirici, Daniel; Pirici, Ionica; Mogoanta, Laurentiu; Margaritescu, Otilia; Tudorica, Valerica; Margaritescu, Claudiu; Ion, Daniela A; Simionescu, Cristiana; Coconu, Marieta

    2012-10-01

    Matrix metalloproteinases (MMPs) are well-recognized denominators for extracellular matrix remodeling in the pathology of both ischemic and hemorrhagic strokes. Recent data on non-nervous system tissue showed intracellular and even intranuclear localizations for different MMPs, and together with this, a plethora of new functions have been proposed for these intracellular active enzymes, but are mostly related to apoptosis induction and malign transformation. In neurons and glial cells, on human tissue, animal models and cell cultures, different active MMPs have been also proven to be located in the intra-cytoplasmic or intra-nuclear compartments, with no clear-cut function. In the present study we show for the first time on human tissue the nuclear expression of MMP-9, mainly in neurons and to a lesser extent in astrocytes. We have studied ischemic and hemorrhagic stroke patients, as well as aged control patients. Age and ischemic suffering seemed to be the best predictors for an elevated MMP-9 nuclear expression, and there was no evidence of a clear-cut extracellular proteolytic activity for this compartment, as revealed by intact vascular basement membranes and assessment of vascular densities. More, the majority of the cells expressing MMP-9 in the nuclear compartment also co-expressed activated-caspase 3, indicating a possible link between nuclear MMP-9 localization and apoptosis in neuronal and glial cells following an ischemic or hemorrhagic event. These results, besides showing for the first time the nuclear localization of MMP-9 on a large series of human stroke and aged brain tissues, raise new questions regarding the unknown spectrum of the functions MMPs in human CNS pathology. © 2011 Japanese Society of Neuropathology.

  1. Pediatric Nonfracture Acute Compartment Syndrome: A Review of 39 Cases.

    Science.gov (United States)

    Livingston, Kristin; Glotzbecker, Michael; Miller, Patricia E; Hresko, Michael T; Hedequist, Daniel; Shore, Benjamin J

    2016-01-01

    Compartment syndrome in the absence of fracture is rare and poorly described within the pediatric literature. The purpose of this study was to report the varying etiologies, risk factors, and treatment outcomes associated with pediatric nonfracture acute compartment syndrome (NFACS). We conducted a retrospective chart review on 37 children who suffered a NFACS and were treated at a single pediatric trauma center between 1997 and 2013. Demographic, diagnostic, treatment, and outcome characteristics were reviewed. Five causal groups were generated: trauma, exercise related (acute presentation after exercise without trauma), infectious, vascular, and postoperative (in the absence of osteotomy). Univariate and multivariate analyses were performed to identify risk factors of NFACS. P-values 39 cases of NFRCS in 37 children [6 females, 31 males, mean age of 11.7 y (SD+7.2 y)]. The leg was the most commonly involved limb (29 cases, 74%). Diagnosis of NFRCS was made either by compartment pressure monitoring [59%, 23/39 cases, mean pressure 66 mm Hg (SD+28)] or by clinical examination. According to etiology, vascular was most common (11/39, 28%), followed by trauma (10/39, 26%) and postoperative (8/39, 21%), with exertion and infection representing a small proportion (6/39, 15% and 4/39, 10%, respectively). Pain was present in 33 cases (85%), swelling in 28 cases (72%), paresthesias in 13 cases (33%), motor deficit in 12 cases (31%), and poor perfusion in 11 cases (28%). Average time from symptom onset to diagnosis was 48 hours (IQR, 9 to 96 h). At surgery, 21 patients (54%) had evidence of myonecrosis. Children required an average of 3 surgeries for wound closure. The median time to follow-up was 232 days (IQR, 73 to 608 d). A total of 54% made a full recovery, whereas 31% suffered a persistent neurological or functional deficit. NFACS in children is associated with a delay in diagnosis and a high rate of myonecrosis. Timely assessment with high clinical suspicion is

  2. Multi-compartment iodine calculations with FIPLOC/IMPAIR

    International Nuclear Information System (INIS)

    Ewig, F.; Allelein, H.J.; Schwarz, S.; Weber, G.

    1996-01-01

    The multi-compartment containment code FIPLOC for the simulation of severe accidents in LWR plants was extended by the integration of the iodine model IMPAIR-3. The iodine model which originally was only drafted for chains of compartments was changed for arbitrary compartment configurations and tightly coupled to the thermal hydraulic part. A main progress with the coupled version FIPLOC-3.0 is the sophisticated modelling of the aerosol iodine behaviour. In a PWR accident the mass of iodine is mainly released in form of CsI aerosol from the primary circuit. In IMPAIR-3 the aerosol behaviour of the species CsI, AgI and IO 3 - is modelled in a very simplified way causing large uncertainties in the calculated distributions. The behaviour of these three aerosol species is treated by the aerosol model MAEROS/MGA. Agglomeration, particle growth by condensation and all deposition processes are calculated. The solubility effect for the hygroscopic species CsI and IO 3 - are comprehended. Furthermore the impact of the iodine decay heat on the thermal hydraulic behaviour is considered. In order to test the code development a preliminary FIPLOC-3.0 calculation was done simulating a German PWR containment for the core melt scenario ND* according to the German risk study phase B. IN the calculation a contact of the core melt with the sump water was assumed and the containment vent line was opened after 70 hours. The result show that the different iodine species are distributed inhomogeneously within the containment. The CsI-aerosol concentrations differ by two orders of magnitude and the I 2 -concentration even by three orders of magnitude. Most of the iodine is assumed to be released as CsI aerosol out of the primary circuit. Since it fastly deposits its contribution to the release into the environment is minor. CsI is however dissolved in the sump, where mainly the gaseous I 2 is created which can react in the containment atmosphere to IO 3 - . (author) 11 figs., 3 tabs., 12

  3. Anxiolytic effects of environmental enrichment attenuate sex-related anxiogenic effects of scopolamine in rats.

    Science.gov (United States)

    Hughes, Robert N; Otto, Maria T

    2013-01-10

    In groups of four same-sexed animals, PVG/c hooded rats were housed for 4.5 months in standard or enriched cages containing several objects that could be explored and manipulated. On separate occasions, each rat then experienced two consecutive daily trials in an open field, a light-dark box or a Y maze with arm inserts that enabled an acquisition trial comprising one black and one white arm to be changed for a retention trial consisting of two black arms. Before their trials in the open field and light-dark box, and following each acquisition trial in the Y maze, the rats received an intraperitoneal injection of 2 mg/kg scopolamine or isotonic saline. In the open field, enrichment led to higher levels of ambulation, walking, rearing and occupancy of the center of the apparatus and shorter emergence latencies from the dark into the light compartment of the light-dark box accompanied by more entries of this compartment. Enrichment also increased entries of and time spent in the changed (or novel) Y-maze arm only for male rats treated with scopolamine. The drug decreased rearing and increased grooming in the open field as well as increasing emergence latencies and decreasing entries of and the time spent on the light compartment of the light-dark box. The main results were interpreted as enrichment having attenuated anxiogenic effects of the behavioral testing and the action of scopolamine for male (but not female) rats in their choices of the novel arm in the Y maze. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. The plasma membrane proteome of germinating barley embryos

    DEFF Research Database (Denmark)

    Hynek, Radovan; Svensson, Birte; Jensen, O.N.

    2009-01-01

    Cereal seed germination involves a complex coordination between different seed tissues. Plasma membranes must play crucial roles in coordination and execution of germination; however, very little is known about seed plasma membrane proteomes due to limited tissue amounts combined...... with amphiphilicity and low abundance of membrane proteins. A fraction enriched in plasma membranes was prepared from embryos dissected from 18 h germinated barley seeds using aqueous two-phase partitioning. Reversed-phase chromatography on C-4 resin performed in micro-spin columns with stepwise elution by 2-propanol...... was used to reduce soluble protein contamination and enrich for hydrophobic proteins. Sixty-one proteins in 14 SDS-PAGE bands were identified by LC-MS/MS and database searches. The identifications provide new insight into the plasma membrane functions in seed germination....

  5. Microbial diversity in different compartments of an aquaponics system.

    Science.gov (United States)

    Schmautz, Zala; Graber, Andreas; Jaenicke, Sebastian; Goesmann, Alexander; Junge, Ranka; Smits, Theo H M

    2017-05-01

    Aquaponics is a solution for sustainable production of fish and plants in a single semi-closed system, where nutrient-rich water from the aquaculture provides nutrients for plant growth. We examined the microbial communities within an experimental aquaponics system. Whereas the fish feces contained a separate community dominated by bacteria of the genus Cetobacterium, the samples from plant roots, biofilter, and periphyton were more similar to each other, while the communities were more diverse. Detailed examination of the data gave the first indications to functional groups of organisms in the different compartments of the aquaponic system. As other nitrifiers other than members of the genus Nitrospira were only present at low numbers, it was anticipated that Nitrospirae may perform the nitrification process in the biofilm.

  6. Cellular endocytic compartment localization of expressed canine CD1 molecules

    DEFF Research Database (Denmark)

    Schjærff, Mette; Keller, Stefan M.; Affolter, Verena K.

    2016-01-01

    CD1 molecules are glycoproteins present primarily on dendritic cells (DCs), which recognize and presenta variety of foreign- and self-lipid antigens to T-cells. Humans have five different CD1 isoforms that sur-vey distinct cellular compartments allowing for recognition of a large repertoire...... onlya diminished GFP expression. In conclusion, canine CD1 transfectants show distinct localization patternsthat are similar to human CD1 proteins with the exception of the canine CD1d isoform, which most likelyis non-functional. These findings imply that canine CD1 localization overall resembles human...... CD1 traf-ficking patterns. This knowledge is important for the understanding of lipid antigen-receptor immunityin the dog....

  7. Abdominal compartment syndrome following abdominoplasty: A case report and review

    Directory of Open Access Journals (Sweden)

    Arash Izadpanah

    2014-01-01

    Full Text Available Abdominoplasty is among the most commonly performed aesthetic procedures in plastic surgery. Despite high complication rate, abdominal contouring procedures are expected to rise in popularity with the advent of bariatric surgery. Patients with a history of gastric bypass surgery have an elevated incidence of small bowel obstruction from internal herniation, which is associated with non-specific upper abdominal pain, nausea, and a decrease in appetite. Internal hernias, when subjected to elevated intra-abdominal pressures, have a high-risk of developing ischemic bowel. We present a case report of patient with previous laparoscopic Roux-en-y gastric bypass who developed acute ischemic bowel leading to abdominal compartment syndrome following abdominoplasty. To the best of our knowledge, this is the first reported case in the literature. We herein emphasise on the subtle symptoms and signs that warrant further investigations in prospective patients for an abdominal contouring procedure with a prior history of gastric bypass surgery.

  8. Geochemical isotope compartment model of the nitrogen cycle

    International Nuclear Information System (INIS)

    Weise, G.; Wetzel, K.; Stiehl, G.

    1981-01-01

    A model of the global cycle of nitrogen and its isotopes is described. It takes into account geochemical reservoirs (nitrogen in magmatic metamorphic, and sedimentary rocks and in the atmosphere) and the nitrogen exchange between magmatic rocks and the outer mantle, the transition of nitrogen exchange between sedimentary rocks and the atmosphere. With the aid of the mathematical formalisms of the compartment theory and on the basis of all available delta 11 N values assumptions regarding the isotope effects in forming these nitrogen fluxes data have been obtained on the degree of the nitrogen exchange between the earth crust and the outer mantle and on other nitrogen fluxes characterizing the global nitrogen cycle. (author)

  9. COMPBRN III: a computer code for modeling compartment fires

    International Nuclear Information System (INIS)

    Ho, V.; Siu, N.; Apostolakis, G.; Flanagan, G.F.

    1986-07-01

    The computer code COMPBRN III deterministically models the behavior of compartment fires. This code is an improvement of the original COMPBRN codes. It employs a different air entrainment model and numerical scheme to estimate properties of the ceiling hot gas layer model. Moreover, COMPBRN III incorporates a number of improvements in shape factor calculations and error checking, which distinguish it from the COMPBRN II code. This report presents the ceiling hot gas layer model employed by COMPBRN III as well as several other modifications. Information necessary to run COMPBRN III, including descriptions of required input and resulting output, are also presented. Simulation of experiments and a sample problem are included to demonstrate the usage of the code. 37 figs., 46 refs

  10. IL4/PGE2 induction of an enlarged early endosomal compartment in mouse macrophages is Rab5-dependent

    International Nuclear Information System (INIS)

    Wainszelbaum, Marisa J.; Proctor, Brandon M.; Pontow, Suzanne E.; Stahl, Philip D.; Barbieri, M. Alejandro

    2006-01-01

    The endosomal compartment and the plasma membrane form a complex partnership that controls signal transduction and trafficking of different molecules. The specificity and functionality of the early endocytic pathway are regulated by a growing number of Rab GTPases, particularly Rab5. In this study, we demonstrate that IL4 (a Th-2 cytokine) and prostaglandin E 2 (PGE 2 ) synergistically induce Rab5 and several Rab effector proteins, including Rin1 and EEA1, and promote the formation of an enlarged early endocytic (EEE) compartment. Endosome enlargement is linked to a substantial induction of the mannose receptor (MR), a well-characterized macrophage endocytic receptor. Both MR levels and MR-mediated endocytosis are enhanced approximately 7-fold. Fluid-phase endocytosis is also elevated in treated cells. Light microscopy and fractionation studies reveal that MR colocalizes predominantly with Rab5a and partially with Rab11, an endosomal recycling pathway marker. Using retroviral expression of Rab5a:S34N, a dominant negative mutant, and siRNA Rab5a silencing, we demonstrate that Rab5a is essential for the large endosome phenotype and for localization of MR in these structures. We speculate that the EEE is maintained by activated Rab5, and that the EEE phenotype is part of some macrophage developmental program such as cell fusion, a characteristic of IL4-stimulated cells

  11. Characterising antimicrobial protein-membrane complexes

    International Nuclear Information System (INIS)

    Xun, Gloria; Dingley, Andrew; Tremouilhac, Pierre

    2009-01-01

    Full text: Antimicrobial proteins (AMPs) are host defence molecules that protect organisms from microbial infection. A number of hypotheses for AMP activity have been proposed which involve protein membrane interactions. However, there is a paucity of information describing AMP-membrane complexes in detail. The aim of this project is to characterise the interactions of amoebapore-A (APA-1) with membrane models using primarily solution-state NMR spectroscopy. APA-1 is an AMP which is regulated by a pH-dependent dimerisation event. Based on the atomic resolution solution structure of monomeric APA-1, it is proposed that this dimerisation is a prerequisite for ring-like hexameric pore formation. Due to the cytotoxicity of APA-1, we have developed a cell-free system to produce this protein. To facilitate our studies, we have adapted the cell-free system to isotope label APA-1. 13 C /15 N -enriched APA-1 sample was achieved and we have begun characterising APA-1 dimerisation and membrane interactions using NMR spectroscopy and other biochemical/biophysical methods. Neutron reflectometry is a surface-sensitive technique and therefore represents an ideal technique to probe how APA-1 interacts with membranes at the molecular level under different physiological conditions. Using Platypus, the pH-induced APA-1-membrane interactions should be detectable as an increase of the amount of protein adsorbed at the membrane surface and changes in the membrane properties. Specifically, detailed information of the structure and dimensions of the protein-membrane complex, the position and amount of the protein in the membrane, and the perturbation of the membrane phospholipids on protein incorporation can be extracted from the neutron reflectometry measurement. Such information will enable critical assessment of current proposed mechanisms of AMP activity in bacterial membranes and complement our NMR studies

  12. The intrinsic renal compartment syndrome: new perspectives in kidney transplantation.

    Science.gov (United States)

    Herrler, Tanja; Tischer, Anne; Meyer, Andreas; Feiler, Sergej; Guba, Markus; Nowak, Sebastian; Rentsch, Markus; Bartenstein, Peter; Hacker, Marcus; Jauch, Karl-Walter

    2010-01-15

    Inflammatory edema after ischemia-reperfusion may impair renal allograft function after kidney transplantation. This study examines the effect of edema-related pressure elevation on renal function and describes a simple method to relieve pressure within the renal compartment. Subcapsular pressure at 6, 12, 24, 48 hr, and 18 days after a 45 min warm ischemia was determined in a murine model of renal ischemia-reperfusion injury. Renal function was measured by Tc-MAG3 scintigraphy and laser Doppler perfusion. Structural damage was assessed by histologic analysis. As a therapeutic approach, parenchymal pressure was relieved by a standardized circular 0.3 mm incision at the lower pole of the kidney capsule. Compared with baseline (0.9+/-0.3 mm Hg), prolonged ischemia was associated with a sevenfold increase in subcapsular pressure 6 hr after ischemia (7.0+/-1.0 mm Hg; P<0.001). Pressure levels remained significantly elevated for 24 hr. Without therapy, a significant decrease in functional parameters was found with considerably reduced tubular excretion rate (33+/-3.5%, P<0.001) and renal perfusion (64.5+/-6.8%, P<0.005). Histologically, severe tissue damage was found. Surgical pressure relief was able to significantly prevent loss of tubular excretion rate (62.5+/-6.8%, P<0.05) and renal blood flow (96.2+/-4.8%; P<0.05) and preserved the integrity of renal structures. Our data support the hypothesis of the existence of a renal compartment syndrome as a consequence of ischemia-reperfusion injury. Surgical pressure relief effectively prevented functional and structural renal impairment, and we speculate that this approach might be of value for improving graft function after renal transplantation.

  13. Characterisation of open-door electrical cabinet fires in compartments

    Energy Technology Data Exchange (ETDEWEB)

    Coutin, M., E-mail: mickael.coutin@irsn.fr; Plumecocq, W.; Zavaleta, P.; Audouin, L.

    2015-05-15

    Highlights: • Heat release rate of electrical cabinet fire source in a vitiated atmosphere. • Experimental database for proper validation the combustible modelling, taking into account the oxygen depletion in an enclosure. • New model for complex fire source. - Abstract: The study of electrical fires is a major concern for fire safety in the industry and more particularly for fire safety in nuclear facilities. To investigate this topic, IRSN conducted a large number of real-scale experiments involving open-door electrical cabinets burning firstly under a calorimetric hood and then inside a mechanically-ventilated compartment. The main challenges are to determine accurately the heat release rate of such a complex fire source in a vitiated atmosphere and to provide an experimental database for validating properly the combustible modelling, taking into account the oxygen depletion in an enclosure. After providing a detailed description of the fire scenarios and of the experimental apparatus, this paper focuses on the characteristic stages of the cabinet fire development, essentially based on the heat release rate time evolution of the fire. The effects of the confinement, of the outlet branch location, of the ventilation management and of the fire barrier on the fire source were then investigated. The reproducibility of electrical cabinet fires is also studied. A new model for complex fire source (applied in this study for open-door electrical cabinet fires) was then developed. This model was introduced in the zone code SYLVIA and the major features of the compartment fire experiments, such as characteristic heat release rate with effect of oxygen depletion and over-pressure peak were then calculated with a rather good agreement for this complex fire source (i.e. electrical cabinet)

  14. RAB-10-Dependent Membrane Transport Is Required for Dendrite Arborization

    Science.gov (United States)

    Zou, Wei; Yadav, Smita; DeVault, Laura; Jan, Yuh Nung; Sherwood, David R.

    2015-01-01

    Formation of elaborately branched dendrites is necessary for the proper input and connectivity of many sensory neurons. Previous studies have revealed that dendritic growth relies heavily on ER-to-Golgi transport, Golgi outposts and endocytic recycling. How new membrane and associated cargo is delivered from the secretory and endosomal compartments to sites of active dendritic growth, however, remains unknown. Using a candidate-based genetic screen in C. elegans, we have identified the small GTPase RAB-10 as a key regulator of membrane trafficking during dendrite morphogenesis. Loss of rab-10 severely reduced proximal dendritic arborization in the multi-dendritic PVD neuron. RAB-10 acts cell-autonomously in the PVD neuron and localizes to the Golgi and early endosomes. Loss of function mutations of the exocyst complex components exoc-8 and sec-8, which regulate tethering, docking and fusion of transport vesicles at the plasma membrane, also caused proximal dendritic arborization defects and led to the accumulation of intracellular RAB-10 vesicles. In rab-10 and exoc-8 mutants, the trans-membrane proteins DMA-1 and HPO-30, which promote PVD dendrite stabilization and branching, no longer localized strongly to the proximal dendritic membranes and instead were sequestered within intracellular vesicles. Together these results suggest a crucial role for the Rab10 GTPase and the exocyst complex in controlling membrane transport from the secretory and/or endosomal compartments that is required for dendritic growth. PMID:26394140

  15. Equine arteritis virus is delivered to an acidic compartment of host cells via clathrin-dependent endocytosis

    International Nuclear Information System (INIS)

    Nitschke, Matthias; Korte, Thomas; Tielesch, Claudia; Ter-Avetisyan, Gohar; Tuennemann, Gisela; Cardoso, M. Cristina; Veit, Michael; Herrmann, Andreas

    2008-01-01

    Equine arteritis virus (EAV) is an enveloped, positive-stranded RNA virus belonging to the family Arteriviridae. Infection by EAV requires the release of the viral genome by fusion with the respective target membrane of the host cell. We have investigated the entry pathway of EAV into Baby Hamster Kindey cells (BHK). Infection of cells assessed by the plaque reduction assay was strongly inhibited by substances which interfere with clathrin-dependent endocytosis and by lysosomotropic compounds. Furthermore, infection of BHK cells was suppressed when clathrin-dependent endocytosis was inhibited by expression of antisense RNA of the clathrin-heavy chain before infection. These results strongly suggest that EAV is taken up via clathrin-dependent endocytosis and is delivered to acidic endosomal compartments

  16. Clarin-1, encoded by the Usher Syndrome III causative gene, forms a membranous microdomain: possible role of clarin-1 in organizing the actin cytoskeleton.

    Science.gov (United States)

    Tian, Guilian; Zhou, Yun; Hajkova, Dagmar; Miyagi, Masaru; Dinculescu, Astra; Hauswirth, William W; Palczewski, Krzysztof; Geng, Ruishuang; Alagramam, Kumar N; Isosomppi, Juha; Sankila, Eeva-Marja; Flannery, John G; Imanishi, Yoshikazu

    2009-07-10

    Clarin-1 is the protein product encoded by the gene mutated in Usher syndrome III. Although the molecular function of clarin-1 is unknown, its primary structure predicts four transmembrane domains similar to a large family of membrane proteins that include tetraspanins. Here we investigated the role of clarin-1 by using heterologous expression and in vivo model systems. When expressed in HEK293 cells, clarin-1 localized to the plasma membrane and concentrated in low density compartments distinct from lipid rafts. Clarin-1 reorganized actin filament structures and induced lamellipodia. This actin-reorganizing function was absent in the modified protein encoded by the most prevalent North American Usher syndrome III mutation, the N48K form of clarin-1 deficient in N-linked glycosylation. Proteomics analyses revealed a number of clarin-1-interacting proteins involved in cell-cell adhesion, focal adhesions, cell migration, tight junctions, and regulation of the actin cytoskeleton. Consistent with the hypothesized role of clarin-1 in actin organization, F-actin-enriched stereocilia of auditory hair cells evidenced structural disorganization in Clrn1(-/-) mice. These observations suggest a possible role for clarin-1 in the regulation and homeostasis of actin filaments, and link clarin-1 to the interactive network of Usher syndrome gene products.

  17. An efficient heuristic for the multi-compartment vehicle routing problem

    OpenAIRE

    Paulo Vitor Silvestrin

    2016-01-01

    We study a variant of the vehicle routing problem that allows vehicles with multiple compartments. The need for multiple compartments frequently arises in practical applications when there are several products of different quality or type, that must be kept or handled separately. The resulting problem is called the multi-compartment vehicle routing problem (MCVRP). We propose a tabu search heuristic and embed it into an iterated local search to solve the MCVRP. In several experiments we analy...

  18. Increased membrane cholesterol in lymphocytes diverts T-cells toward an inflammatory response.

    Directory of Open Access Journals (Sweden)

    Jacqueline Surls

    Full Text Available Cell signaling for T-cell growth, differentiation, and apoptosis is initiated in the cholesterol-rich microdomains of the plasma membrane known as lipid rafts. Herein, we investigated whether enrichment of membrane cholesterol in lipid rafts affects antigen-specific CD4 T-helper cell functions. Enrichment of membrane cholesterol by 40-50% following squalene administration in mice was paralleled by an increased number of resting CD4 T helper cells in periphery. We also observed sensitization of the Th1 differentiation machinery through co-localization of IL-2Rα, IL-4Rα, and IL-12Rβ2 subunits with GM1 positive lipid rafts, and increased STAT-4 and STAT-5 phosphorylation following membrane cholesterol enrichment. Antigen stimulation or CD3/CD28 polyclonal stimulation of membrane cholesterol-enriched, resting CD4 T-cells followed a path of Th1 differentiation, which was more vigorous in the presence of increased IL-12 secretion by APCs enriched in membrane cholesterol. Enrichment of membrane cholesterol in antigen-specific, autoimmune Th1 cells fostered their organ-specific reactivity, as confirmed in an autoimmune mouse model for diabetes. However, membrane cholesterol enrichment in CD4(+Foxp3(+ T-reg cells did not alter their suppressogenic function. These findings revealed a differential regulatory effect of membrane cholesterol on the function of CD4 T-cell subsets. This first suggests that membrane cholesterol could be a new therapeutic target to modulate the immune functions, and second that increased membrane cholesterol in various physiopathological conditions may bias the immune system toward an inflammatory Th1 type response.

  19. Purification and proteomics of pathogen-modified vacuoles and membranes

    Directory of Open Access Journals (Sweden)

    Jo-Ana eHerweg

    2015-06-01

    Full Text Available Certain pathogenic bacteria adopt an intracellular lifestyle and proliferate in eukaryotic host cells. The intracellular niche protects the bacteria from cellular and humoral components of the mammalian immune system, and at the same time, allows the bacteria to gain access to otherwise restricted nutrient sources. Yet, intracellular protection and access to nutrients comes with a price, i.e. the bacteria need to overcome cell-autonomous defense mechanisms, such as the bactericidal endocytic pathway. While a few bacteria rupture the early phagosome and escape into the host cytoplasm, most intracellular pathogens form a distinct, degradation-resistant and replication-permissive membranous compartment. Intracellular bacteria that form unique pathogen vacuoles include Legionella, Mycobacterium, Chlamydia, Simkania and Salmonella species. In order to understand the formation of these pathogen niches on a global scale and in a comprehensive and quantitative manner, an inventory of compartment-associated host factors is required. To this end, the intact pathogen compartments need to be isolated, purified and biochemically characterized. Here, we review recent progress on the isolation and purification of pathogen-modified vacuoles and membranes, as well as their proteomic characterization by mass spectrometry and different validation approaches. These studies provide the basis for further investigations on the specific mechanisms of pathogen-driven compartment formation.

  20. PWR fuel of high enrichment with erbia and enriched gadolinia

    International Nuclear Information System (INIS)

    Bejmer, Klaes-Håkan; Malm, Christian

    2011-01-01

    Today standard PWR fuel is licensed for operation up to 65-70 MWd/kgU, which in most cases corresponds to an enrichment of more than 5 w/o "2"3"5U. Due to criticality safety reason of storage and transportation, only fuel up to 5 w/o "2"3"5U enrichment is so far used. New fuel storage installations and transportation casks are necessary investments before the reactivity level of the fresh fuel can be significantly increased. These investments and corresponding licensing work takes time, and in the meantime a solution that requires burnable poisons in all pellets of the fresh high-enriched fuel might be used. By using very small amounts of burnable absorber in every pellet the initial reactivity can be reduced to today's levels. This study presents core calculations with fuel assemblies enriched to almost 6 w/o "2"3"5U mixed with a small amount of erbia. Some of the assemblies also contain gadolinia. The results are compared to a reference case containing assemblies with 4.95 w/o "2"3"5U without erbia, utilizing only gadolinia as burnable poison. The comparison shows that the number of fresh fuel assemblies can be reduced by 21% (which increases the batch burnup by 24%) by utilizing the erbia fuel concept. However, increased cost of uranium due to higher enrichment is not fully compensated for by the cost gain due to the reduction of the number assemblies. Hence, the fuel cycle cost becomes slightly higher for the high enrichment erbia case than for the reference case. (author)

  1. One-step isolation of plasma membrane proteins using magnetic beads with immobilized concanavalin A

    DEFF Research Database (Denmark)

    Lee, Yu-Chen; Block, Gregory; Chen, Huiwen

    2008-01-01

    We have developed a simple method for isolating and purifying plasma membrane proteins from various cell types. This one-step affinity-chromatography method uses the property of the lectin concanavalin A (ConA) and the technique of magnetic bead separation to obtain highly purified plasma membrane...... proteins from crude membrane preparations or cell lines. ConA is immobilized onto magnetic beads by binding biotinylated ConA to streptavidin magnetic beads. When these ConA magnetic beads were used to enrich plasma membranes from a crude membrane preparation, this procedure resulted in 3.7-fold enrichment...... of plasma membrane marker 5'-nucleotidase activity with 70% recovery of the activity in the crude membrane fraction of rat liver. In agreement with the results of 5'-nucleotidase activity, immunoblotting with antibodies specific for a rat liver plasma membrane protein, CEACAM1, indicated that CEACAM1...

  2. Water transport between CNS compartments: contributions of aquaporins and cotransporters

    DEFF Research Database (Denmark)

    MacAulay, N; Zeuthen, T

    2010-01-01

    or hydrocephalus. The molecular pathways by which water molecules cross the cell membranes of the brain are not well-understood, although the discovery of aquaporin 4 (AQP4) in the brain improved our understanding of some of these transport processes, particularly under pathological conditions. In the present...

  3. Polyphophoinositides components of plant nuclear membranes

    International Nuclear Information System (INIS)

    Hendrix, K.W.; Boss, W.F.

    1987-01-01

    The polyphosphoinositides, phosphatidylinositol monophosphate (PIP) and phosphatidylinositol bisphosphate (PIP 2 ), have been shown to be important components in signal transduction in many animal cells. Recently, these lipids have been found to be associated with plasma membrane but not microsomal membrane isolated from fusogenic wild carrot cells; however, in that study the lipids of the nuclear membrane were not analyzed. Since polyphosphoinositides had been shown to be associated with the nuclear membranes as well as the plasma membrane in some animal cells, it was important to determine whether they were associated with plant nuclear membranes as well. Cells were labeled for 18h with [ 3 H] inositol and the nuclei were isolated by a modification of the procedure of Saxena et al. Preliminary lipid analyses indicate lower amount of PIP and PIP 2 in nuclear membranes compared to whole protoplasts. This suggests that the nuclear membranes of carrot cells are not enriched in PIP and PIP 2 ; however, the Triton X-100 used during the nuclear isolation procedure may have affected the recovery of the lipids. Experiments are in progress to determine the effects of Triton X-100 on lipid extraction

  4. Electrochemical membrane reactor: In situ separation and recovery of chromic acid and metal ions

    International Nuclear Information System (INIS)

    Khan, Jeeshan; Tripathi, Bijay P.; Saxena, Arunima; Shahi, Vinod K.

    2007-01-01

    An electrochemical membrane reactor with three compartments (anolyte, catholyte and central compartment) based on in-house-prepared cation- and anion-exchange membrane was developed to achieve in situ separation and recovery of chromic acid and metal ions. The physicochemical and electrochemical properties of the ion-exchange membrane under standard operating conditions reveal its suitability for the proposed reactor. Experiments using synthetic solutions of chromate and dichromate of different concentrations were carried out to study the feasibility of the process. Electrochemical reactions occurring at the cathode and anode under operating conditions are proposed. It was observed that metal ion migrated through the cation-exchange membrane from central compartment to catholyte and OH - formation at the cathode leads to the formation of metal hydroxide. Simultaneously, chromate ion migrated through the anion-exchange membrane from central compartment to the anolyte and formed chromic acid by combining H + produced their by oxidative water splitting. Thus a continuous decay in the concentration of chromate and metal ion was observed in the central compartment, which was recovered separately in the anolyte and catholyte, respectively, from their mixed solution. This process was completely optimized in terms of operating conditions such as initial concentration of chromate and metal ions in the central compartment, the applied cell voltage, chromate and metal ion flux, recovery percentage, energy consumption, and current efficiency. It was concluded that chromic acid and metal ions can be recovered efficiently from their mixed solution leaving behind the uncharged organics and can be reused as their corresponding acid and base apart from the purifying water for further applications

  5. High enrichment to low enrichment core's conversion. Accidents analysis

    International Nuclear Information System (INIS)

    Abbate, P.; Rubio, R.; Doval, A.; Lovotti, O.

    1990-01-01

    This work analyzes the different accidents that may occur in the reactor's facility after the 20% high-enriched uranium core's conversion. The reactor (of 5 thermal Mw), built in the 50's and 60's, is of the 'swimming pool' type, with light water and fuel elements of the curve plates MTR type, enriched at 93.15 %. This analysis includes: a) accidents by reactivity insertion; b) accidents by coolant loss; c) analysis by flow loss and d) fission products release. (Author) [es

  6. A New Approach to Uncertainty Reduction in Launch Vehicle Compartment Venting

    Data.gov (United States)

    National Aeronautics and Space Administration — Launch vehicle compartments are vented to the external environment during ascent to minimize undesirable structural loading. Prediction of venting performance is an...

  7. Gaseous diffusion -- the enrichment workhorse

    International Nuclear Information System (INIS)

    Shoemaker, J.E. Jr.

    1984-01-01

    Construction of the first large-scale gaseous diffusion facility was started as part of the Manhattan Project in Oak Ridge, Tennessee, in 1943. This facility, code named ''K-25,'' began operation in January 1945 and was fully on stream by September 1945. Four additional process buildings were later added in Oak Ridge as the demand for enriched uranium escalated. New gaseous diffusion plants were constructed at Paducah, Kentucky, and Portsmouth, Ohio, during this period. The three gaseous diffusion plants were the ''workhorses'' which provided the entire enriched uranium demand for the United States during the 1950s and 1960s. As the demand for enriched uranium for military purposes decreased during the early 1960s, power to the diffusion plants was curtailed to reduce production. During the 1960s, as plans for the nuclear power industry were formulated, the role of the diffusion plants gradually changed from providing highly-enriched uranium for the military to providing low-enriched uranium for power reactors

  8. Uranium enrichment. Technology, economics, capacity

    International Nuclear Information System (INIS)

    Voigt, W.R. Jr.; Saire, D.E.; Gestson, D.K.; Peske, S.E.; Vanstrum, P.R.

    1983-01-01

    Large-scale enrichment of uranium has now been carried out for 40 years. While the gaseous diffusion process was the original choice of several countries and continues today to provide the major component of the world production of separative work, the last two decades have witnessed the development of a number of alternative processes for enrichment. These processes, which are being studied and deployed around the world, offer a wide range of technical and economic characteristics which will be useful in assuring adequate capacity to meet projected reactor fuel market needs through the rest of this century at competitive prices. With present uncertainties in future enriched uranium needs, it is apparent that flexibility in the deployment and operation of any enrichment process will be one of the prime considerations for the future. More economical production of separative work not only can have a beneficial impact on reactor fuel costs, but also tends to conserve natural uranium resources. This paper reviews the world scene in the enrichment component of the fuel cycle, including existing or planned commercial-scale facilities and announced R+D efforts on various processes. (author)

  9. Uranium enrichment: technology, economics, capacity

    Energy Technology Data Exchange (ETDEWEB)

    Voigt, Jr., W. R.; Vanstrum, P. R.; Saire, D. E.; Gestson, D. K.; Peske, S. E.

    1982-08-01

    Large-scale enrichment of uranium has now been carried out for 40 years. While the gaseous diffusion process was the original choice of several countries and continues today to provide the major component of the world production of separative work, the last two decades have witnessed the development of a number of alternative processes for enrichment. These processes, which are being studied and deployed around the world, offer a wide range of technical and economic characteristics which will be useful in assuring adequate capacity to meet projected reactor fuel market needs through the rest of this century at competitive prices. With present uncertainties in future enriched uranium needs, it is apparent that flexibility in the deployment and operation of any enrichment process will be one of the prime considerations for the future. More economical production of separative work not only can have a beneficial impact on reactor fuel costs, but also tends to conserve natural uranium resources. This paper reviews the world scene in the enrichment component of the fuel cycle, including existing or planned commercial-scale facilities and announced R and D efforts on various processes.

  10. Uranium enrichment: technology, economics, capacity

    International Nuclear Information System (INIS)

    Voigt, W.R. Jr.; Vanstrum, P.R.; Saire, D.E.; Gestson, D.K.; Peske, S.E.

    1982-01-01

    Large-scale enrichment of uranium has now been carried out for 40 years. While the gaseous diffusion process was the original choice of several countries and continues today to provide the major component of the world production of separative work, the last two decades have witnessed the development of a number of alternative processes for enrichment. These processes, which are being studied and deployed around the world, offer a wide range of technical and economic characteristics which will be useful in assuring adequate capacity to meet projected reactor fuel market needs through the rest of this century at competitive prices. With present uncertainties in future enriched uranium needs, it is apparent that flexibility in the deployment and operation of any enrichment process will be one of the prime considerations for the future. More economical production of separative work not only can have a beneficial impact on reactor fuel costs, but also tends to conserve natural uranium resources. This paper reviews the world scene in the enrichment component of the fuel cycle, including existing or planned commercial-scale facilities and announced R and D efforts on various processes

  11. Cellular vacuoles induced by Mycoplasma pneumoniae CARDS toxin originate from Rab9-associated compartments.

    Directory of Open Access Journals (Sweden)

    Coreen Johnson

    Full Text Available Recently, we identified an ADP-ribosylating and vacuolating cytotoxin in Mycoplasma pneumoniae designated Community Acquired Respiratory Distress Syndrome (CARDS toxin. In this study we show that vacuoles induced by recombinant CARDS (rCARDS toxin are acidic and derive from the endocytic pathway as determined by the uptake of neutral red and the fluid-phase marker, Lucifer yellow, respectively. Also, we demonstrate that the formation of rCARDS toxin-associated cytoplasmic vacuoles is inhibited by the vacuolar ATPase inhibitor, bafilomycin A1, and the ionophore, monensin. To examine the ontogeny of these vacuoles, we analyzed the distribution of endosomal and lysosomal membrane markers during vacuole formation and observed the enrichment of the late endosomal GTPase, Rab9, around rCARDS toxin-induced vacuoles. Immunogold-labeled Rab9 and overexpression of green fluorescent-tagged Rab9 further confirmed vacuolar association. The late endosomal- and lysosomal-associated membrane proteins, LAMP1 and LAMP2, also localized to the vacuolar membranes, while the late endosomal protein, Rab7, and early endosomal markers, Rab5 and EEA1, were excluded. HeLa cells expressing dominant-negative (DN Rab9 exhibited markedly reduced vacuole formation in the presence of rCARDS toxin, in contrast to cells expressing DN-Rab7, highlighting the importance of Rab9 function in rCARDS toxin-induced vacuolation. Our findings reveal the unique Rab9-association with rCARDS toxin-induced vacuoles and its possible relationship to the characteristic histopathology that accompanies M. pneumoniae infection.

  12. Nanoscale Membrane Domain Formation Driven by Cholesterol

    DEFF Research Database (Denmark)

    Javanainen, Matti; Martinez-Seara, Hector; Vattulainen, Ilpo

    2017-01-01

    Biological membranes generate specific functions through compartmentalized regions such as cholesterol-enriched membrane nanodomains that host selected proteins. Despite the biological significance of nanodomains, details on their structure remain elusive. They cannot be observed via microscopic...... dipalmitoylphosphatidylcholine and cholesterol - the "minimal standard" for nanodomain formation. The simulations reveal how cholesterol drives the formation of fluid cholesterol-rich nanodomains hosting hexagonally packed cholesterol-poor lipid nanoclusters, both of which show registration between the membrane leaflets....... The complex nanodomain substructure forms when cholesterol positions itself in the domain boundary region. Here cholesterol can also readily flip-flop across the membrane. Most importantly, replacing cholesterol with a sterol characterized by a less asymmetric ring region impairs the emergence of nanodomains...

  13. Acidocalcisomes as calcium- and polyphosphate-storage compartments during embryogenesis of the insect Rhodnius prolixus Stahl.

    Directory of Open Access Journals (Sweden)

    Isabela Ramos

    Full Text Available BACKGROUND: The yolk of insect eggs is a cellular domain specialized in the storage of reserve components for embryo development. The reserve macromolecules are stored in different organelles and their interactions with the embryo cells are mostly unknown. Acidocalcisomes are lysosome-related organelles characterized by their acidic nature, high electron density and large content of polyphosphate bound to several cations. In this work, we report the presence of acidocalcisome-like organelles in eggs of the insect vector Rhodnius prolixus. METHODOLOGY/PRINCIPAL FINDINGS: Characterization of the elemental composition of electron-dense vesicles by electron probe X-ray microanalysis revealed a composition similar to that previously described for acidocalcisomes. Following subcellular fractionation experiments, fractions enriched in acidocalcisomes were obtained and characterized. Immunofluorescence showed that polyphosphate polymers and the vacuolar proton translocating pyrophosphatase (V-H(+-PPase, considered as a marker for acidocalcisomes are found in the same vesicles and that these organelles are mainly localized in the egg cortex. Polyphosphate quantification showed that acidocalcisomes contain a significant amount of polyphosphate detected at day-0 eggs. Elemental analyses of the egg fractions showed that 24.5±0.65% of the egg calcium are also stored in such organelles. During embryogenesis, incubation of acidocalcisomes with acridine orange showed that these organelles are acidified at day-3 (coinciding with the period of yolk mobilization and polyphosphate quantification showed that the levels of polyphosphate tend to decrease during early embryogenesis, being approximately 30% lower at day-3 compared to day-0 eggs. CONCLUSIONS: We found that acidocalcisomes are present in the eggs and are the main storage compartments of polyphosphate and calcium in the egg yolk. As such components have been shown to be involved in a series of dynamic

  14. A Systematic Approach to Marital Enrichment.

    Science.gov (United States)

    Dinkmeyer, Don; Carlson, Jon

    1986-01-01

    Presents a systematic approach to enriching marital relationships. The history and current status of marital enrichment is reviewed. An Adlerian approach to marital enrichment is described. Applications of the program in enrichment groups, marriage therapy and couple groups are included. (Author)

  15. Enrichment of light hydrocarbon mixture

    Science.gov (United States)

    Yang,; Dali, [Los Alamos, NM; Devlin, David [Santa Fe, NM; Barbero, Robert S [Santa Cruz, NM; Carrera, Martin E [Naperville, IL; Colling, Craig W [Warrenville, IL

    2010-08-10

    Light hydrocarbon enrichment is accomplished using a vertically oriented distillation column having a plurality of vertically oriented, nonselective micro/mesoporous hollow fibers. Vapor having, for example, both propylene and propane is sent upward through the distillation column in between the hollow fibers. Vapor exits neat the top of the column and is condensed to form a liquid phase that is directed back downward through the lumen of the hollow fibers. As vapor continues to ascend and liquid continues to countercurrently descend, the liquid at the bottom of the column becomes enriched in a higher boiling point, light hydrocarbon (propane, for example) and the vapor at the top becomes enriched in a lower boiling point light hydrocarbon (propylene, for example). The hollow fiber becomes wetted with liquid during the process.

  16. PC based uranium enrichment analyser

    International Nuclear Information System (INIS)

    Madan, V.K.; Gopalakrishana, K.R.; Bairi, B.R.

    1991-01-01

    It is important to measure enrichment of unirradiated nuclear fuel elements during production as a quality control measure. An IBM PC based system has recently been tested for enrichment measurements for Nuclear Fuel Complex (NFC), Hyderabad. As required by NFC, the system has ease of calibration. It is easy to switch the system from measuring enrichment of fuel elements to pellets and also automatically store the data and the results. The system uses an IBM PC plug in card to acquire data. The card incorporates programmable interval timers (8253-5). The counter/timer devices are executed by I/O mapped I/O's. A novel algorithm has been incorporated to make the system more reliable. The application software has been written in BASIC. (author). 9 refs., 1 fig

  17. Advances in uranium enrichment processes

    International Nuclear Information System (INIS)

    Rae, H.K.; Melvin, J.G.; Slater, J.B.

    1986-05-01

    Advances in gas centrifuges and development of the atomic vapour laser isotope separation process promise substantial reductions in the cost of enriched uranium. The resulting reduction in LWR fuel costs could seriously erode the economic advantage of CANDU, and in combination with LWR design improvements, shortened construction times and increased operational reliability could allow the LWR to overtake CANDU. CANDU's traditional advantages of neutron economy and high reliability may no longer be sufficient - this is the challenge. The responses include: combining neutron economy and dollar economy by optimizing CANDU for slightly enriched uranium fuel; developing cost-reducing improvements in design, manufacture and construction; and reducing the cost of heavy water. Technology is a renewable resource which must be continually applied to a product for it to remain competitive in the decades to come. Such innovation is a prerequisite to Canada increasing her share of the international market for nuclear power stations. The higher burn-up achievable with enriched fuel in CANDU can reduce the fuel cycle costs by 20 to 40 percent for a likely range of costs for yellowcake and separative work. Alternatively, some of the benefits of a higher fissile content can take the form of a cheaper reactor core containing fewer fuel channels and less heavy water, and needing only a single fuelling machine. An opportunity that is linked to this need to introduce an enriched uranium fuel cycle into CANDU is to build an enrichment business in Canada. This could offer greater value added to our uranium exports, security of supply for enriched CANDUs, technological growth in Canada and new employment opportunities. AECL has a study in progress to define this opportunity

  18. Laboratory studies of 235U enrichment by chemical separation methods

    International Nuclear Information System (INIS)

    Daloisi, P.J.; Orlett, M.J.; Tracy, J.W.; Saraceno, A.J.

    1976-01-01

    Laboratory experiments on 235 U enrichment processes based on column redox ion exchange, electrodialysis, and gas exchange chromatography performed from August 1972 to September 1974 are summarized. Effluent from a 50 to 50 weight mixture of U +4 and U +6 (as UO 2 2+ ), at a total uranium concentration of 5 mg U per ml in 0.25N H 2 SO 4 -0.03N NaF solution, passing through a 100 cm length cation exchange column at 0.5 ml/min flow rates, was enriched in 235 U by 1.00090 +- .00012. The enriched fraction was mostly in the +6 valence form while the depleted fraction was U +4 retained on the resin. At flow rates of 2 ml/min, the enrichment factor decreases to 1.00033 +- .00003. In the electrodialysis experiments, the fraction of uranium diffusing through the membranes (mostly as +6 valence state) in 4.2 hours is enriched in 235 U by 1.00096 +- .00012. Gas exchange chromatography tests involved dynamic and static exposure of UF 6 over NaF. In dynamic tests, no significant change in isotopic abundance occurred in the initial one-half weight cut of UF 6 . The measured relative 235 U/ 238 U mole ratios were 1.00004 +- .00004 for these runs. In static runs, enrichment became evident. For the NaF(UF 6 )/sub x/-UF 6 system, there is 235 U depletion in the gas phase, with a single-stage factor of 1.00033 at 100 0 C and 1.00025 at 25 0 C after 10 days of equilibration. The single-stage or unit holdup time is impractically long for all three chemical processes

  19. Uranium enriched granites in Sweden

    International Nuclear Information System (INIS)

    Wilson, M.R.; Aakerblom, G.

    1980-01-01

    Granites with uranium contents higher than normal occur in a variety of geological settings in the Swedish Precambrian, and represent a variety of granite types and ages. They may have been generated by (1) the anatexis of continental crust (2) processes occurring at a much greater depth. They commonly show enrichement in F, Sn, W and/or Mo. Only in one case is an important uranium mineralization thought to be directly related to a uranium-enriched granite, while the majority of epigenetic uranium mineralizations with economic potential are related to hydrothermal processes in areas where the bedrock is regionally uranium-enhanced. (Authors)

  20. Uranium enrichment. 1980 annual report

    International Nuclear Information System (INIS)

    1981-05-01

    This report contains data and related information on the production of enriched uranium at the gaseous diffusion plants and an update on the construction and project control center for the gas centrifuge plant. Power usage at the gaseous diffusion plants is illustrated. The report contains several glossy color pictures of the plants and processes described. In addition to gaseous diffusion and the centrifuge process, three advanced isotope separation process are now being developed. The business operation of the enrichment plants is described; charts on revenue, balance sheets, and income statements are included

  1. Multi-compartment iodine calculations with FIPLOC/IMPAIR

    Energy Technology Data Exchange (ETDEWEB)

    Ewig, F; Allelein, H J [Gesellschaft fuer Anlagen- und Reaktorsicherheit mbH (GRS), Koeln (Germany); Schwarz, S; Weber, G [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) mbH, Garching (Germany)

    1996-12-01

    The multi-compartment containment code FIPLOC for the simulation of severe accidents in LWR plants was extended by the integration of the iodine model IMPAIR-3. The iodine model was changed for arbitrary compartment configurations and tightly coupled to the thermal hydraulic part. A main progress with the coupled version FIPLOC-3.0 is the sophisticated modelling of the aerosol iodine behaviour. In a PWR accident the mass of iodine is mainly released in form of CsI aerosol from the primary circuit. In IMPAIR-3 the aerosol behaviour of the species CsI, AgI and IO{sub 3}{sup -} is modelled in a very simplified way causing large uncertainties in the calculated distributions. The behaviour of these three aerosol species is treated by the aerosol model MAEROS/MGA. Agglomeration, particle growth by condensation and all deposition processes are calculated. The solubility effect for the hygroscopic species CsI and IO{sub 3}{sup -} are comprehended. Furthermore the impact of the iodine decay heat on the thermal hydraulic behaviour is considered. In order to test the code development a preliminary FIPLOC-3.0 calculation was done simulating a German PWR containment for the core melt scenario ND* according to the German risk study phase B. IN the calculation a contact of the core melt with the sump water was assumed and the containment vent line was opened after 70 hours. The result show that the different iodine species are distributed inhomogeneously within the containment. The CsI-aerosol concentrations differ by two orders of magnitude and the I{sub 2}-concentration even by three orders of magnitude. Most of the iodine is assumed to be released as CsI aerosol out of the primary circuit. Since it fastly deposits its contribution to the release into the environment is minor. CsI is however dissolved in the sump, where mainly the gaseous I{sub 2} is created which can react in the containment atmosphere to IO{sub 3}{sup -}. (author) 11 figs., 3 tabs., 12 refs.

  2. Prospects and problems of uranium enrichment

    International Nuclear Information System (INIS)

    Imai, Ryukichi

    1974-01-01

    The problem of uranium enrichment now concerns principally peaceful nuclear power generation. With the current oil crisis, energy resources assume unprecedented importance. However, the requirements for enriched uranium vary with the vicissitude of the world situation in nuclear power generation; the enterprise of uranium enrichment is related to economic aspect. The following matters are described: dimension of enrichment problem, political factors, changes in requirements, projects in each country, and strategy of enrichment in Japan. (Mori, K.)

  3. Uranium enrichment in the United States

    International Nuclear Information System (INIS)

    Hill, J.H.; Parks, J.W.

    1975-01-01

    History, improvement programs, status of electrical power availability, demands for uranium enrichment, operating plan for the U. S. enriching facilities, working inventory of enriched uranium, possible factors affecting deviations in the operating plan, status of gaseous diffusion technology, status of U. S. gas centrifuge advances, transfer of enrichment technology, gaseous diffusion--gas centrifuge comparison, new enrichment capacity, U. S. separative work pricing, and investment in nuclear energy are discussed. (LK)

  4. Influence of the fire location and the size of a compartment on the heat and smoke flow out of the compartment

    Science.gov (United States)

    Wegrzyński, Wojciech; Konecki, Marek

    2018-01-01

    This paper presents results of CFD and scale modelling of the flow of heat and smoke inside and outside of a compartment, in case of fire. Estimation of mass flow out of a compartment is critical, as it is the boundary condition in further considerations related to the exhaust of the smoke from a building - also in analysis related to the performance of natural ventilation in wind conditions. Both locations of the fire and the size of compartment were addressed as possible variables, which influence the mass and the temperature of smoke that leaves the room engulfed in fire. Results of the study show small to none influence of both size of the compartment and the location of the fire, on the mass flow of smoke exiting the room. On the same time, both of these parameters influence the temperature of the smoke - in larger compartments lower average temperatures of the smoke layer, but higher maximum values were observed. Results of this study may be useful also in the determination of the worst case scenarios for structural analysis, or in the investiga tion of the spread of fire through the compartment. Based on the results presented in this study, researchers can attribute an expert judgement choice of fire location, as a single scenario that is representative of a larger amount of probable scenarios.

  5. Challenges in the Development of Functional Assays of Membrane Proteins

    Directory of Open Access Journals (Sweden)

    Sophie Demarche

    2012-11-01

    Full Text Available Lipid bilayers are natural barriers of biological cells and cellular compartments. Membrane proteins integrated in biological membranes enable vital cell functions such as signal transduction and the transport of ions or small molecules. In order to determine the activity of a protein of interest at defined conditions, the membrane protein has to be integrated into artificial lipid bilayers immobilized on a surface. For the fabrication of such biosensors expertise is required in material science, surface and analytical chemistry, molecular biology and biotechnology. Specifically, techniques are needed for structuring surfaces in the micro- and nanometer scale, chemical modification and analysis, lipid bilayer formation, protein expression, purification and solubilization, and most importantly, protein integration into engineered lipid bilayers. Electrochemical and optical methods are suitable to detect membrane activity-related signals. The importance of structural knowledge to understand membrane protein function is obvious. Presently only a few structures of membrane proteins are solved at atomic resolution. Functional assays together with known structures of individual membrane proteins will contribute to a better understanding of vital biological processes occurring at biological membranes. Such assays will be utilized in the discovery of drugs, since membrane proteins are major drug targets.

  6. Cytoskeletal Components Define Protein Location to Membrane Microdomains*

    Science.gov (United States)

    Szymanski, Witold G.; Zauber, Henrik; Erban, Alexander; Gorka, Michal; Wu, Xu Na; Schulze, Waltraud X.

    2015-01-01

    The plasma membrane is an important compartment that undergoes dynamic changes in composition upon external or internal stimuli. The dynamic subcompartmentation of proteins in ordered low-density (DRM) and disordered high-density (DSM) membrane phases is hypothesized to require interactions with cytoskeletal components. Here, we systematically analyzed the effects of actin or tubulin disruption on the distribution of proteins between membrane density phases. We used a proteomic screen to identify candidate proteins with altered submembrane location, followed by biochemical or cell biological characterization in Arabidopsis thaliana. We found that several proteins, such as plasma membrane ATPases, receptor kinases, or remorins resulted in a differential distribution between membrane density phases upon cytoskeletal disruption. Moreover, in most cases, contrasting effects were observed: Disruption of actin filaments largely led to a redistribution of proteins from DRM to DSM membrane fractions while disruption of tubulins resulted in general depletion of proteins from the membranes. We conclude that actin filaments are necessary for dynamic movement of proteins between different membrane phases and that microtubules are not necessarily important for formation of microdomains as such, but rather they may control the protein amount present in the membrane phases. PMID:26091700

  7. Limited and selective transfer of plasma membrane glycoproteins to membrane of secondary lysosomes

    International Nuclear Information System (INIS)

    Haylett, T.; Thilo, L.

    1986-01-01

    Radioactive galactose, covalently bound to cell surface glycoconjugates on mouse macrophage cells, P388D 1 , was used as a membrane marker to study the composition, and the kinetics of exchange, of plasma membrane-derived constituents in the membrane of secondary lysosomes. Secondary lysosomes were separated from endosomes and plasma membrane by self-forming Percoll density gradients. Horseradish peroxidase, taken up by fluid-phase pinocytosis, served as a vesicle contents marker to monitor transfer of endosomal contents into secondary lysosomes. Concurrently, the fraction of plasma membrane-derived label of secondary lysosomes increased by first order kinetics from 4 PAGE, labeled molecules of M/sub r/ 160-190 kD were depleted and of the M/sub r/ 100-120 kD were enriched in lysosome membrane compared with the relative composition of label on the cell surface. No corresponding selectivity was observed for the degradation of label, with all M/sub r/ classes being affected to the same relative extent. The results indicate that endocytosis-derived transfer of plasma membrane constitutents to secondary lysosomes is a limited and selective process, and that only ∼1% of internalized membrane is recycled via a membrane pool of secondary lysosomes

  8. Role for chlamydial inclusion membrane proteins in inclusion membrane structure and biogenesis.

    Directory of Open Access Journals (Sweden)

    Jeffrey Mital

    Full Text Available The chlamydial inclusion membrane is extensively modified by the insertion of type III secreted effector proteins. These inclusion membrane proteins (Incs are exposed to the cytosol and share a common structural feature of a long, bi-lobed hydrophobic domain but little or no primary amino acid sequence similarity. Based upon secondary structural predictions, over 50 putative inclusion membrane proteins have been identified in Chlamydia trachomatis. Only a limited number of biological functions have been defined and these are not shared between chlamydial species. Here we have ectopically expressed several C. trachomatis Incs in HeLa cells and find that they induce the formation of morphologically distinct membranous vesicular compartments. Formation of these vesicles requires the bi-lobed hydrophobic domain as a minimum. No markers for various cellular organelles were observed in association with these vesicles. Lipid probes were incorporated by the Inc-induced vesicles although the lipids incorporated were dependent upon the specific Inc expressed. Co-expression of Inc pairs indicated that some colocalized in the same vesicle, others partially overlapped, and others did not associate at all. Overall, it appears that Incs may have an intrinsic ability to induce membrane formation and that individual Incs can induce membranous structures with unique properties.

  9. Plant lipid environment and membrane enzymes: the case of the plasma membrane H+-ATPase.

    Science.gov (United States)

    Morales-Cedillo, Francisco; González-Solís, Ariadna; Gutiérrez-Angoa, Lizbeth; Cano-Ramírez, Dora Luz; Gavilanes-Ruiz, Marina

    2015-04-01

    Several lipid classes constitute the universal matrix of the biological membranes. With their amphipathic nature, lipids not only build the continuous barrier that confers identity to every cell and organelle, but they are also active actors that modulate the activity of the proteins immersed in the lipid bilayer. The plasma membrane H(+)-ATPase, an enzyme from plant cells, is an excellent example of a transmembrane protein whose activity is influenced by the hydrophilic compartments at both sides of the membrane and by the hydrophobic domains of the lipid bilayer. As a result, an extensive documentation of the effect of numerous amphiphiles in the enzyme activity can be found. Detergents, membrane glycerolipids, and sterols can produce activation or inhibition of the enzyme activity. In some cases, these effects are associated with the lipids of the membrane bulk, but in others, a direct interaction of the lipid with the protein is involved. This review gives an account of reports related to the action of the membrane lipids on the H(+)-ATPase activity.

  10. Seismic analysis of reactor exhaust-air Filter Compartment

    International Nuclear Information System (INIS)

    Gong, C.; Funderburk, E.L.; Jerrel, J.W.; Vashi, K.M.

    1991-01-01

    This paper presents the results of a scoping analysis for assessment of seismic adequacy of a Filter Compartments (FC) that is part of an Airborne Activity Confinement System (AACS) in K, L, and P Reactors at the Savannah River Site (SRS). For an expeditious assessment and to increase the possibility of showing the adequacy of the FC, the finite element model incorporated certain conceptual reinforcing modifications suggested by a previous study. The model also set the vertical displacements at zero at the interface between the FC and the rail dolly, upon which the FC rests by gravity. In addition, the rail-dolly was assumed to be rigid and rigidly attached to the rails. The analysis was performed using the dynamic modal superposition response spectra capability of the ABAQUS computer code. Certain modelling approximations and linearized representation of boundary conditions were employed for utilization of the code and the selected analysis capability. The analysis results showed that the FC stresses and deformations were within the yield limit and that the structural integrity of the FC and the operability of the filters can be preserved as required for the defined seismic event consistent with the linearization assumptions, modelling simplifications, and incorporation of the conceptual reinforcing modifications. However, the rail-dolly rigidity, the FC hold-down to the rails must be ensured for this scoping analysis to be valid. 2 refs

  11. Status of the International Space Station Waste and Hygiene Compartment

    Science.gov (United States)

    Walker, Stephanie; Zahner, Christopher

    2010-01-01

    The Waste and Hygiene Compartment (WHC) serves as the primary system for removal and containment of metabolic waste and hygiene activities on board the United States segment of the International Space Station (ISS). The WHC was launched on ULF 2 and is currently in the U.S. Laboratory and is integrated into the Water Recovery System (WRS) where pretreated urine is processed by the Urine Processor Assembly (UPA). The waste collection part of the WHC system is derived from the Service Module system and was provided by RSC-Energia along with additional hardware to allow for urine delivery to the UPA. The System has been integrated in an ISS standard equipment rack structure for use on the U.S. segment of the ISS. The system has experienced several events of interest during the deployment, checkout, and operation of the system during its first year of use and these will be covered in this paper. Design and on-orbit performance will also be discussed.

  12. International Space Station USOS Waste and Hygiene Compartment Development

    Science.gov (United States)

    Link, Dwight E., Jr.; Broyan, James Lee, Jr.; Gelmis, Karen; Philistine, Cynthia; Balistreri, Steven

    2007-01-01

    The International Space Station (ISS) currently provides human waste collection and hygiene facilities in the Russian Segment Service Module (SM) which supports a three person crew. Additional hardware is planned for the United States Operational Segment (USOS) to support expansion of the crew to six person capability. The additional hardware will be integrated in an ISS standard equipment rack structure that was planned to be installed in the Node 3 element; however, the ISS Program Office recently directed implementation of the rack, or Waste and Hygiene Compartment (WHC), into the U.S. Laboratory element to provide early operational capability. In this configuration, preserved urine from the WHC waste collection system can be processed by the Urine Processor Assembly (UPA) in either the U.S. Lab or Node 3 to recover water for crew consumption or oxygen production. The human waste collection hardware is derived from the Service Module system and is provided by RSC-Energia. This paper describes the concepts, design, and integration of the WHC waste collection hardware into the USOS including integration with U.S. Lab and Node 3 systems.

  13. Connexin Communication Compartments and Wound Repair in Epithelial Tissue.

    Science.gov (United States)

    Chanson, Marc; Watanabe, Masakatsu; O'Shaughnessy, Erin M; Zoso, Alice; Martin, Patricia E

    2018-05-03

    Epithelial tissues line the lumen of tracts and ducts connecting to the external environment. They are critical in forming an interface between the internal and external environment and, following assault from environmental factors and pathogens, they must rapidly repair to maintain cellular homeostasis. These tissue networks, that range from a single cell layer, such as in airway epithelium, to highly stratified and differentiated epithelial surfaces, such as the epidermis, are held together by a junctional nexus of proteins including adherens, tight and gap junctions, often forming unique and localised communication compartments activated for localised tissue repair. This review focuses on the dynamic changes that occur in connexins, the constituent proteins of the intercellular gap junction channel, during wound-healing processes and in localised inflammation, with an emphasis on the lung and skin. Current developments in targeting connexins as corrective therapies to improve wound closure and resolve localised inflammation are also discussed. Finally, we consider the emergence of the zebrafish as a concerted whole-animal model to study, visualise and track the events of wound repair and regeneration in real-time living model systems.

  14. Mathematical properties and parameter estimation for transit compartment pharmacodynamic models.

    Science.gov (United States)

    Yates, James W T

    2008-07-03

    One feature of recent research in pharmacodynamic modelling has been the move towards more mechanistically based model structures. However, in all of these models there are common sub-systems, such as feedback loops and time-delays, whose properties and contribution to the model behaviour merit some mathematical analysis. In this paper a common pharmacodynamic model sub-structure is considered: the linear transit compartment. These models have a number of interesting properties as the length of the cascade chain is increased. In the limiting case a pure time-delay is achieved [Milsum, J.H., 1966. Biological Control Systems Analysis. McGraw-Hill Book Company, New York] and the initial behaviour becoming increasingly sensitive to parameter value perturbation. It is also shown that the modelled drug effect is attenuated, though the duration of action is longer. Through this analysis the range of behaviours that such models are capable of reproducing are characterised. The properties of these models and the experimental requirements are discussed in order to highlight how mathematical analysis prior to experimentation can enhance the utility of mathematical modelling.

  15. Connexin Communication Compartments and Wound Repair in Epithelial Tissue

    Directory of Open Access Journals (Sweden)

    Marc Chanson

    2018-05-01

    Full Text Available Epithelial tissues line the lumen of tracts and ducts connecting to the external environment. They are critical in forming an interface between the internal and external environment and, following assault from environmental factors and pathogens, they must rapidly repair to maintain cellular homeostasis. These tissue networks, that range from a single cell layer, such as in airway epithelium, to highly stratified and differentiated epithelial surfaces, such as the epidermis, are held together by a junctional nexus of proteins including adherens, tight and gap junctions, often forming unique and localised communication compartments activated for localised tissue repair. This review focuses on the dynamic changes that occur in connexins, the constituent proteins of the intercellular gap junction channel, during wound-healing processes and in localised inflammation, with an emphasis on the lung and skin. Current developments in targeting connexins as corrective therapies to improve wound closure and resolve localised inflammation are also discussed. Finally, we consider the emergence of the zebrafish as a concerted whole-animal model to study, visualise and track the events of wound repair and regeneration in real-time living model systems.

  16. Clonal dominance and transplantation dynamics in hematopoietic stem cell compartments.

    Directory of Open Access Journals (Sweden)

    Peter Ashcroft

    2017-10-01

    Full Text Available Hematopoietic stem cells in mammals are known to reside mostly in the bone marrow, but also transitively passage in small numbers in the blood. Experimental findings have suggested that they exist in a dynamic equilibrium, continuously migrating between these two compartments. Here we construct an individual-based mathematical model of this process, which is parametrised using existing empirical findings from mice. This approach allows us to quantify the amount of migration between the bone marrow niches and the peripheral blood. We use this model to investigate clonal hematopoiesis, which is a significant risk factor for hematologic cancers. We also analyse the engraftment of donor stem cells into non-conditioned and conditioned hosts, quantifying the impact of different treatment scenarios. The simplicity of the model permits a thorough mathematical analysis, providing deeper insights into the dynamics of both the model and of the real-world system. We predict the time taken for mutant clones to expand within a host, as well as chimerism levels that can be expected following transplantation therapy, and the probability that a preconditioned host is reconstituted by donor cells.

  17. Enriched uranium recovery flowsheet improvements

    International Nuclear Information System (INIS)

    Holt, D.L.

    1986-01-01

    Savannah River uses 7.5% TBP to recover and purify enriched uranium. Adequate decontamination from fission products is necessary to reduce personnel exposure and to ensure that the enriched uranium product meets specifications. Initial decontamination of the enriched uranium from the fission products is carried out in the 1A bank, 16 stages of mixer-settlers. Separation of the enriched uranium from the fission product, 95 Zr, has been adequate, but excessive solvent degradation caused by the long phase contact times in the mixer-settlers has limited the 95 Zr decontamination factor (DF). An experimental program is investigating the replacement of the current 1A bank with either centrifugal contactors or a combination of centrifugal contactors and mixer-settlers. Experimental work completed has compared laboratory-scale centrifugal contactors and mixer-settlers for 95 Zr removal efficiencies. Feed solutions spiked with actual plant solutions were used. The 95 Zr DF was significantly better in the mixer-settlers than in the centrifugal contactors. As a result of this experimental study, a hybrid equipment flowsheet has been proposed for plant use. The hybrid equipment flowsheet combines the advantages of both types of solvent extraction equipment. Centrifugal contactors would be utilized in the extraction and initial scrub sections, followed by additional scrub stages of mixer-settlers

  18. Enrichment plant management and safeguards

    International Nuclear Information System (INIS)

    Hurt, N.H.

    1978-01-01

    The next increment of enrichment at Portsmouth will be gas centrifuge. The safeguards program at Portsmouth is discussed, including the DYMCAS system, the computerization, and the detectors. Control of the material access areas is discussed. The licensee material surveillance and verification program is also described

  19. The changing face of enrichment

    International Nuclear Information System (INIS)

    Dunckel, E.

    1981-01-01

    The AIS techniques considered are atomic vapour laser isotope separation, molecular laser isotope separation and plasma separation. The future of the AIS technique and their advantages over the gas centrifuge method are discussed in terms of economics, power consideration, and possible enrichment contracts. (U.K.)

  20. Environmental Development Plan: uranium enrichment

    International Nuclear Information System (INIS)

    1979-09-01

    This Environmental Development Plan identifies and examines the environmental, health, safety, and socioeconomic concerns and corresponding requirements associated with the DOE research, development, demonstration, and operation of the Uranium Enrichment program, including the gaseous diffusion process, the centrifuge process, centrifuge rotor fabrication, and related research and development activities

  1. Are certain fractures at increased risk for compartment syndrome after civilian ballistic injury?

    Science.gov (United States)

    Meskey, Thomas; Hardcastle, John; O'Toole, Robert V

    2011-11-01

    Compartment syndrome after ballistic fracture is uncommon but potentially devastating. Few data are available to help guide clinicians regarding risk factors for developing compartment syndrome after ballistic fractures. Our primary hypothesis was that ballistic fractures of certain bones would be at higher risk for development of compartment syndrome. A retrospective review at a Level I trauma center from 2001 through 2007 yielded 650 patients with 938 fractures resulting from gunshots. We reviewed all operative notes, clinic notes, discharge summaries, and data from our prospective trauma database. Cases in which the attending orthopedic surgeon diagnosed compartment syndrome and performed fasciotomy were considered cases with compartment syndrome. We excluded all prophylactic fasciotomies. Univariate analyses were conducted to identify risk factors associated with development of compartment syndrome. Twenty-six (2.8%) of the 938 fractures were associated with compartment syndrome. Only fibular (11.6%) and tibial (11.4%) fractures had incidence significantly higher than baseline for all ballistic fractures (p Ballistic fractures of the fibula and tibia are at increased risk for development of compartment syndrome over other ballistic fractures. We recommend increased vigilance when treating these injuries, particularly if the fracture is in the proximal aspect of the bone or is associated with vascular injury.

  2. Compartment syndrome, rhabdomyolysis and risk of acute renal failure as complications of the lithotomy position.

    NARCIS (Netherlands)

    Bocca, G.; Moorselaar, R.J.A. van; Feitz, W.F.J.; Staak, F.H.J.M. van der; Monnens, L.A.H.

    2002-01-01

    Compartment syndrome, rhabdomyolysis and the risk of acute renal failure are potential complications of the lithotomy position. A six-year-old girl is described who developed a compartment syndrome with rhabdomyolysis after prolonged surgery in the lithotomy position. This complication occurred

  3. 75 FR 81 - Special Conditions: Boeing Model 787-8 Airplane; Overhead Flightcrew Rest Compartment Occupiable...

    Science.gov (United States)

    2010-01-04

    ... and protective breathing equipment (PBE). This analysis should consider the possibility of fire in any..., mechanical or structural failure, or persons standing below or against the crew rest compartment outlets. One..., volume of the compartment, and the ventilation rate. The system must have sufficient extinguishing agent...

  4. AERODYNAMIC IMPROVEMENT OF KhADI 33 RACING CAR RADIATOR COMPARTMENT

    Directory of Open Access Journals (Sweden)

    A. Avershyn

    2011-01-01

    Full Text Available Aerodynamic characteristics of radiator compartment of KhADI 33 racing car on the basis of the decision of the interfaced problem of internal and external aerodynamics are numerically investigated. The rational variant of radiator compartment which is characterized by high throughput and low level of non-uniformity of speed field at the input is offered.

  5. 46 CFR 105.25-7 - Ventilation systems for cargo tank or pumping system compartment.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Ventilation systems for cargo tank or pumping system... Requirements-When Cargo Tanks Are Installed Below Decks § 105.25-7 Ventilation systems for cargo tank or pumping system compartment. (a) Each compartment shall be provided with a mechanical exhaust system...

  6. 14 CFR 25.858 - Cargo or baggage compartment smoke or fire detection systems.

    Science.gov (United States)

    2010-01-01

    ... detection systems. 25.858 Section 25.858 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT... Construction Fire Protection § 25.858 Cargo or baggage compartment smoke or fire detection systems. If... must be met for each cargo or baggage compartment with those provisions: (a) The detection system must...

  7. 19 CFR 24.13 - Car, compartment, and package seals; kind, procurement.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Car, compartment, and package seals; kind... SECURITY; DEPARTMENT OF THE TREASURY CUSTOMS FINANCIAL AND ACCOUNTING PROCEDURE § 24.13 Car, compartment.... Customs] [Can. Transit] for use on railroad cars, and “United States-Canada Customs” for use on samples...

  8. Validation of a multiple compartment model for the transport of cesium through animals

    International Nuclear Information System (INIS)

    Assimakopoulos, P.A.; Ioannides, K.G.; Pakou, A.A.

    1991-01-01

    A general multiple compartment model, which describes the transport of trace elements through animals is presented. This model considers a system of K interconnected compartments of volume V i , i = 1,2,....,K, each containing, at a given time t, N i molecules of a trace substance. (5 figs.)

  9. Stiffness and thickness of fascia do not explain chronic exertional compartment syndrome

    DEFF Research Database (Denmark)

    Dahl, Morten; Hansen, Philip; Stål, Per

    2011-01-01

    Chronic exertional compartment syndrome is diagnosed based on symptoms and elevated intramuscular pressure and often is treated with fasciotomy. However, what contributes to the increased intramuscular pressure remains unknown.......Chronic exertional compartment syndrome is diagnosed based on symptoms and elevated intramuscular pressure and often is treated with fasciotomy. However, what contributes to the increased intramuscular pressure remains unknown....

  10. 30 CFR 57.19107 - Precautions for work in compartment affected by hoisting operation.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Precautions for work in compartment affected by hoisting operation. 57.19107 Section 57.19107 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... AND NONMETAL MINES Personnel Hoisting Shafts § 57.19107 Precautions for work in compartment affected...

  11. 30 CFR 56.19107 - Precautions for work in compartment affected by hoisting operation.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Precautions for work in compartment affected by hoisting operation. 56.19107 Section 56.19107 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... NONMETAL MINES Personnel Hoisting Shafts § 56.19107 Precautions for work in compartment affected by...

  12. 77 FR 19148 - Special Conditions: Airbus, A350-900 Series Airplane; Crew Rest Compartments

    Science.gov (United States)

    2012-03-30

    ... accommodates side-by-side placement of LD-3 containers in the cargo compartment. The basic A350-900 series... total overhead crew rest compartment length, the exit separation should not be less than 50 percent of... by curtains. Flight tests must be conducted to show compliance with this requirement. Each system or...

  13. 46 CFR 58.16-20 - Ventilation of compartments containing gas-consuming appliances.

    Science.gov (United States)

    2010-10-01

    ... appliances. 58.16-20 Section 58.16-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED... and Heating § 58.16-20 Ventilation of compartments containing gas-consuming appliances. (a) Compartments containing gas-consuming appliances which are located above the weather deck shall be fitted with...

  14. Robotic membranes

    DEFF Research Database (Denmark)

    Ramsgaard Thomsen, Mette

    2008-01-01

    The relationship between digital and analogue is often constructed as one of opposition. The perception that the world is permeated with underlying patterns of data, describing events and matter alike, suggests that information can be understood apart from the substance to which it is associated......, and that its encoded logic can be constructed and reconfigured as an isolated entity. This disembodiment of information from materiality implies that an event like a thunderstorm, or a material like a body, can be described equally by data, in other words it can be read or written. The following prototypes......, 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...

  15. Role of amphipathic helix of a herpesviral protein in membrane deformation and T cell receptor downregulation.

    Directory of Open Access Journals (Sweden)

    Chan-Ki Min

    2008-11-01

    Full Text Available Lipid rafts are membrane microdomains that function as platforms for signal transduction and membrane trafficking. Tyrosine kinase interacting protein (Tip of T lymphotropic Herpesvirus saimiri (HVS is targeted to lipid rafts in T cells and downregulates TCR and CD4 surface expression. Here, we report that the membrane-proximal amphipathic helix preceding Tip's transmembrane (TM domain mediates lipid raft localization and membrane deformation. In turn, this motif directs Tip's lysosomal trafficking and selective TCR downregulation. The amphipathic helix binds to the negatively charged lipids and induces liposome tubulation, the TM domain mediates oligomerization, and cooperation of the membrane-proximal helix with the TM domain is sufficient for localization to lipid rafts and lysosomal compartments, especially the mutivesicular bodies. These findings suggest that the membrane-proximal amphipathic helix and TM domain provide HVS Tip with the unique ability to deform the cellular membranes in lipid rafts and to downregulate TCRs potentially through MVB formation.

  16. Mechanisms underlying anomalous diffusion in the plasma membrane.

    Science.gov (United States)

    Krapf, Diego

    2015-01-01

    The plasma membrane is a complex fluid where lipids and proteins undergo diffusive motion critical to biochemical reactions. Through quantitative imaging analyses such as single-particle tracking, it is observed that diffusion in the cell membrane is usually anomalous in the sense that the mean squared displacement is not linear with time. This chapter describes the different models that are employed to describe anomalous diffusion, paying special attention to the experimental evidence that supports these models in the plasma membrane. We review models based on anticorrelated displacements, such as fractional Brownian motion and obstructed diffusion, and nonstationary models such as continuous time random walks. We also emphasize evidence for the formation of distinct compartments that transiently form on the cell surface. Finally, we overview heterogeneous diffusion processes in the plasma membrane, which have recently attracted considerable interest. Copyright © 2015. Published by Elsevier Inc.

  17. Heavy subunit of cell surface Gal/GalNAc lectin (Hgl) undergoes degradation via endo-lysosomal compartments in Entamoeba histolytica.

    Science.gov (United States)

    Verma, Kuldeep; Datta, Sunando

    2017-06-14

    The human gut parasite Entamoeba histolytica uses a multifunctional virulence factor, Hgl, a cell surface transmembrane receptor subunit of Gal/GalNAc lectin that contributes to adhesion, invasion, cytotoxicity and immune response in the host. At present, the physiologic importance of Hgl receptor is mostly known for pathogenicity of E. histolytica. However, the molecular mechanisms of Hgl trafficking events and their association with the intracellular membrane transport machinery are largely unknown. We used biochemical and microscopy-based assays to understand the Hgl trafficking in the amoebic trophozoites. Our results suggest that the Hgl is constitutively degraded through delivery into amoebic lysosome-like compartments. Further, we also observed that the Hgl was significantly colocalized with amoebic Rab GTPases such as EhRab5, EhRab7A, and EhRab11B. While, we detected association of Hgl with all these Rab GTPases in early vacuolar compartments, only EhRab7A remains associated with Hgl till its transport to amoebic lysosome-like compartments.

  18. Mouse mammary tumor virus uses mouse but not human transferrin receptor 1 to reach a low pH compartment and infect cells

    International Nuclear Information System (INIS)

    Wang Enxiu; Obeng-Adjei, Nyamekye; Ying Qihua; Meertens, Laurent; Dragic, Tanya; Davey, Robert A.; Ross, Susan R.

    2008-01-01

    Mouse mammary tumor virus (MMTV) is a pH-dependent virus that uses mouse transferrin receptor 1 (TfR1) for entry into cells. Previous studies demonstrated that MMTV could induce pH 5-dependent fusion-from-with of mouse cells. Here we show that the MMTV envelope-mediated cell-cell fusion requires both the entry receptor and low pH (pH 5). Although expression of the MMTV envelope and TfR1 was sufficient to mediate low pH-dependent syncytia formation, virus infection required trafficking to a low pH compartment; infection was independent of cathepsin-mediated proteolysis. Human TfR1 did not support virus infection, although envelope-mediated syncytia formation occurred with human cells after pH 5 treatment and this fusion depended on TfR1 expression. However, although the MMTV envelope bound human TfR1, virus was only internalized and trafficked to a low pH compartment in cells expressing mouse TfR1. Thus, while human TfR1 supported cell-cell fusion, because it was not internalized when bound to MMTV, it did not function as an entry receptor. Our data suggest that MMTV uses TfR1 for all steps of entry: cell attachment, induction of the conformational changes in Env required for membrane fusion and internalization to an appropriate acidic compartment

  19. Unrecognized anterior compartment syndrome following ankle fracture surgery: a case report.

    Science.gov (United States)

    Seyahi, Aksel; Uludag, Serkan; Akman, Senol; Demirhan, Mehmet

    2009-01-01

    A 35-year-old male sustained a lateral malleolar fracture while playing football. The fracture was treated by open reduction and internal fixation with a tourniquet. The next day, the patient returned with pain and swelling of the ankle and was admitted again to the hospital with a suspected diagnosis of cellulitis. Ten hours later, the patient developed the symptoms of anterior compartment syndrome. Emergency open fasciotomy of the anterior compartment was performed. The retrospective analysis of the patient's history was suggestive of a predisposition to an exercise-induced compartment syndrome. We think that exertional increase of the compartmental pressure before the injury and the tourniquet used during surgery contributed together to the development of compartment syndrome. Physicians should be vigilant in identifying the features of compartment syndrome when managing patients injured during a sporting activity.

  20. SMAS Fusion Zones Determine the Subfascial and Subcutaneous Anatomy of the Human Face: Fascial Spaces, Fat Compartments, and Models of Facial Aging.

    Science.gov (United States)

    Pessa, Joel E

    2016-05-01

    Fusion zones between superficial fascia and deep fascia have been recognized by surgical anatomists since 1938. Anatomical dissection performed by the author suggested that additional superficial fascia fusion zones exist. A study was performed to evaluate and define fusion zones between the superficial and the deep fascia. Dissection of fresh and minimally preserved cadavers was performed using the accepted technique for defining anatomic spaces: dye injection combined with cross-sectional anatomical dissection. This study identified bilaminar membranes traveling from deep to superficial fascia at consistent locations in all specimens. These membranes exist as fusion zones between superficial and deep fascia, and are referred to as SMAS fusion zones. Nerves, blood vessels and lymphatics transition between the deep and superficial fascia of the face by traveling along and within these membranes, a construct that provides stability and minimizes shear. Bilaminar subfascial membranes continue into the subcutaneous tissues as unilaminar septa on their way to skin. This three-dimensional lattice of interlocking horizontal, vertical, and oblique membranes defines the anatomic boundaries of the fascial spaces as well as the deep and superficial fat compartments of the face. This information facilitates accurate volume augmentation; helps to avoid facial nerve injury; and provides the conceptual basis for understanding jowls as a manifestation of enlargement of the buccal space that occurs with age. © 2016 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

  1. Cation trapping by cellular acidic compartments: Beyond the concept of lysosomotropic drugs

    Energy Technology Data Exchange (ETDEWEB)

    Marceau, François, E-mail: francois.marceau@crchul.ulaval.ca [Centre de recherche en rhumatologie et immunologie, Centre Hospitalier Universitaire de Québec, Québec QC, Canada G1V 4G2 (Canada); Bawolak, Marie-Thérèse [Centre de recherche en rhumatologie et immunologie, Centre Hospitalier Universitaire de Québec, Québec QC, Canada G1V 4G2 (Canada); Lodge, Robert [Centre de recherche en infectiologie, Centre Hospitalier Universitaire de Québec, Québec QC, Canada G1V 4G2 (Canada); Bouthillier, Johanne; Gagné-Henley, Angélique [Centre de recherche en rhumatologie et immunologie, Centre Hospitalier Universitaire de Québec, Québec QC, Canada G1V 4G2 (Canada); Gaudreault, René C. [Unité des Biotechnologies et de Bioingénierie, Centre Hospitalier Universitaire de Québec, Québec QC, Canada G1L 3L5 (Canada); Morissette, Guillaume [Centre de recherche en rhumatologie et immunologie, Centre Hospitalier Universitaire de Québec, Québec QC, Canada G1V 4G2 (Canada)

    2012-02-15

    “Lysosomotropic” cationic drugs are known to concentrate in acidic cell compartments due to low retro-diffusion of the protonated molecule (ion trapping); they draw water by an osmotic mechanism, leading to a vacuolar response. Several aspects of this phenomenon were recently reexamined. (1) The proton pump vacuolar (V)-ATPase is the driving force of cationic drug uptake and ensuing vacuolization. In quantitative transport experiments, V-ATPase inhibitors, such as bafilomycin A1, greatly reduced the uptake of cationic drugs and released them in preloaded cells. (2) Pigmented or fluorescent amines are effectively present in a concentrated form in the large vacuoles. (3) Consistent with V-ATPase expression in trans-Golgi, lysosomes and endosomes, a fraction of the vacuoles is consistently labeled with trans-Golgi markers and protein secretion and endocytosis are often inhibited in vacuolar cells. (4) Macroautophagic signaling (accumulation of lipidated and membrane-bound LC3 II) and labeling of the large vacuoles by the autophagy effector LC3 were consistently observed in cells, precisely at incubation periods and amine concentrations that cause vacuolization. Vacuoles also exhibit late endosome/lysosome markers, because they may originate from such organelles or because macroautophagosomes fuse with lysosomes. Autophagosome persistence is likely due to the lack of resolution of autophagy, rather than to nutritional deprivation. (5) Increased lipophilicity decreases the threshold concentration for the vacuolar and autophagic cytopathology, because simple diffusion into cells is limiting. (6) A still unexplained mitotic arrest is consistently observed in cells loaded with amines. An extended recognition of relevant clinical situations is proposed for local or systemic drug administration.

  2. Cation trapping by cellular acidic compartments: Beyond the concept of lysosomotropic drugs

    International Nuclear Information System (INIS)

    Marceau, François; Bawolak, Marie-Thérèse; Lodge, Robert; Bouthillier, Johanne; Gagné-Henley, Angélique; Gaudreault, René C.; Morissette, Guillaume

    2012-01-01

    “Lysosomotropic” cationic drugs are known to concentrate in acidic cell compartments due to low retro-diffusion of the protonated molecule (ion trapping); they draw water by an osmotic mechanism, leading to a vacuolar response. Several aspects of this phenomenon were recently reexamined. (1) The proton pump vacuolar (V)-ATPase is the driving force of cationic drug uptake and ensuing vacuolization. In quantitative transport experiments, V-ATPase inhibitors, such as bafilomycin A1, greatly reduced the uptake of cationic drugs and released them in preloaded cells. (2) Pigmented or fluorescent amines are effectively present in a concentrated form in the large vacuoles. (3) Consistent with V-ATPase expression in trans-Golgi, lysosomes and endosomes, a fraction of the vacuoles is consistently labeled with trans-Golgi markers and protein secretion and endocytosis are often inhibited in vacuolar cells. (4) Macroautophagic signaling (accumulation of lipidated and membrane-bound LC3 II) and labeling of the large vacuoles by the autophagy effector LC3 were consistently observed in cells, precisely at incubation periods and amine concentrations that cause vacuolization. Vacuoles also exhibit late endosome/lysosome markers, because they may originate from such organelles or because macroautophagosomes fuse with lysosomes. Autophagosome persistence is likely due to the lack of resolution of autophagy, rather than to nutritional deprivation. (5) Increased lipophilicity decreases the threshold concentration for the vacuolar and autophagic cytopathology, because simple diffusion into cells is limiting. (6) A still unexplained mitotic arrest is consistently observed in cells loaded with amines. An extended recognition of relevant clinical situations is proposed for local or systemic drug administration.

  3. 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

  4. CFD analysis of flow in engine compartment of large urban bus; Ogata bus no engine room nai nagare kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Hoshino, H; Otake, M; Iioka, K [Nissan Diesel Motor Co. Ltd., Saitama (Japan); Sato, K [Subaru Research Center Co. Ltd., Tokyo (Japan)

    1997-10-01

    A CFD simulation was performed to analyze the air flow in the engine compartment of a large urban bus. The conventional simulation technique takes a long time to perform the parameter study of a complex engine compartment shape. In this study, the use of orthogonal grids made modeling the engine compartment easy, so parameter study on modification of the engine compartment structure could be conducted in a short time. Thus this simulation enables engineers to more clearly understand the air flow patterns in the engine compartment, and to get guidlines for modifying the compartment structure to improve the cooling performance. 1 ref., 12 figs.

  5. The commercial role for centrifuge enrichment

    International Nuclear Information System (INIS)

    Readle, P.H.; Wilcox, P.

    1987-01-01

    The enrichment market is extremely competitive and capacity greatly exceeds demand. BNFL [British Nuclear Fuels Ltd.] is in a unique position in having commercial experience of the two enrichment technologies currently used industrially: diffusion, and centrifuge enrichment through its associate company Urenco. In addition, BNFL is developing laser enrichment techniques as part of a UK development programme. The paper describes the enrichment market, briefly discusses the relative merits of the various methods of uranium enrichment and concludes that the gas centrifuge will be best able to respond to market needs for at least the remainder of the century. (author)

  6. Enrichment into the 21st century

    International Nuclear Information System (INIS)

    Rutkowski, E.

    1995-01-01

    This article discusses the future of the enrichment services market into the next century. It is estimated that demand for enrichment services will reach 31 million SWU by the end of the century and remain constant for the following 10 years. The current world enrichment capacity is 44 million SWU, or some 50% ahead of the demand. This oversupply is projected to continue into the next century, but in spite of this, several suppliers are planning new enrichment facilities. HEU as a source of enriched uranium is examined. Overall, long-term prices for enrichment services are expected to decline in the coming decade

  7. Pre test parametric studies on single compartment vented enclosure

    International Nuclear Information System (INIS)

    Sharma, Pavan K.; Gera, B.; Singh, R.K.; Vaze, K.K.

    2011-01-01

    Establishing a proper design fire scenario is a challenging task and essential component for conducting fire safety design of buildings. A design fire scenario is a qualitative description of a fire with time identifying key events that characterize the fire (ignition, growth, flashover, fully-developed, and decay stages of fire). Proper fire safety design requires the appropriate selection of design fires against which the performance of the building is evaluated. The selection of the design fires directly impacts all aspects of fire safety performance, including the structural fire resistance, compartmentation against fire spread, egress systems, manual or automatic detection systems, suppression systems, and smoke control. The parameters affecting design fires include, the type, amount and arrangement of combustible materials, the ventilation conditions (air supply conditions, door/window open), and size of the compartment of fire origin. A design fire is a quantitative description of the characteristics of a fire, such as heat release rate (HRR), size of fire and its rate of spread, yield of products of combustion, and hot gas temperatures. Design fires are based on fire scenarios that replicate real fires. Six Computational Fluid Dynamics (CFD) numerical simulations were conducted in order to investigate the effect of fire load on fire dynamics in a) iso corner fire configuration b) IIT Delhi single compartment of a size of 5.0 m long, 5.0 m wide and 5.0 m high with doorway opening of 1m x 3m with centre fire of size 0.5 m x 0.5m. These types of simulation are carried out for deciding about the instrumentation scheme, safety aspect, and optimization of proposed experiments for National Fire Test Facility as pretest calculations. The simulations results are summarized in various identified applied parameter which are useful in terms of understanding the complex fire dynamics, validating the numerical tolls against experiments and using them (in form of values

  8. Neutrophil glycoprotein Mo1 is an integral membrane protein of plasma membranes and specific granules

    International Nuclear Information System (INIS)

    Stevenson, K.B.; Nauseef, W.M.; Clark, R.A.

    1987-01-01

    The glucoprotein Mo1 has previously been demonstrated to be on the cell surface and in the specific granule fraction of neutrophils and to be translocated to the cell surface during degranulation. It is not known, however, whether Mo1 is an integral membrane protein or a soluble, intragranular constituent loosely associated with the specific granule membrane. Purified neutrophils were disrupted by nitrogen cavitation and separated on Percoll density gradients into four fractions enriched for azurophilic granules, specific granules, plasma membrane, and cytosol, respectively. The glycoproteins in these fractions were labeled with 3 H-borohydride reduction, extracted with Triton X-114, and immunoprecipitated with 60.3, an anti-Mo1 monoclonal antibody. Mo1 was detected only in the specific granule and plasma membrane fractions and partitioned exclusively into the detergent-rich fraction consistent with Mo1 being an integral membrane protein. In addition, treatment of specific granule membranes with a high salt, high urea buffer to remove adsorbed or peripheral proteins failed to dissociate Mo1. These data support the hypothesis that Mo1 is an integral membrane protein of plasma and specific granule membranes in human neutrophils

  9. Improved surface property of PVDF membrane with amphiphilic zwitterionic copolymer as membrane additive

    International Nuclear Information System (INIS)

    Li Jianhua; Li Mizi; Miao Jing; Wang Jiabin; Shao Xisheng; Zhang Qiqing

    2012-01-01

    An attempt to improve hydrophilicity and anti-fouling properties of PVDF membranes, a novel amphiphilic zwitterionic copolymer poly(vinylidene fluoride)-graft-poly(sulfobetaine methacrylate) (PVDF-g-PSBMA) was firstly synthesized by atom transfer radical polymerization (ATRP) and used as amphiphilic copolymer additive in the preparation of PVDF membranes. The PVDF-g-PSBMA/PVDF blend membranes were prepared by immersion precipitation process. Fourier transform infrared attenuated reflection spectroscopy (FTIR-ATR) and X-ray photoelectronic spectroscopy (XPS) measurements confirmed that PSBMA brushes from amphiphilic additives were preferentially segregated to membrane-coagulant interface during membrane formation. The morphology of membranes was characterized by scanning electron microscopy (SEM). Water contact angle measurements showed that the surface hydrophilicity of PVDF membranes was improved significantly with the increasing of amphiphilic copolymer PVDF-g-PSBMA in cast solution. Protein static adsorption experiment and dynamic fouling resistance experiment revealed that the surface enrichment of PSBMA brush endowed PVDF blend membrane great improvement of surface anti-fouling ability.

  10. Improved surface property of PVDF membrane with amphiphilic zwitterionic copolymer as membrane additive

    Energy Technology Data Exchange (ETDEWEB)

    Li Jianhua, E-mail: jhli_2005@163.com [Institute of Biomedical and Pharmaceutical Technology and College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350001 (China); Li Mizi; Miao Jing; Wang Jiabin; Shao Xisheng [Institute of Biomedical and Pharmaceutical Technology and College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350001 (China); Zhang Qiqing, E-mail: zhangqiq@126.com [Institute of Biomedical and Pharmaceutical Technology and College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350001 (China) and Institute of Biomedical Engineering, Chinese Academy of Medical Science, Peking Union Medical College, Tianjin 300192 (China)

    2012-06-15

    An attempt to improve hydrophilicity and anti-fouling properties of PVDF membranes, a novel amphiphilic zwitterionic copolymer poly(vinylidene fluoride)-graft-poly(sulfobetaine methacrylate) (PVDF-g-PSBMA) was firstly synthesized by atom transfer radical polymerization (ATRP) and used as amphiphilic copolymer additive in the preparation of PVDF membranes. The PVDF-g-PSBMA/PVDF blend membranes were prepared by immersion precipitation process. Fourier transform infrared attenuated reflection spectroscopy (FTIR-ATR) and X-ray photoelectronic spectroscopy (XPS) measurements confirmed that PSBMA brushes from amphiphilic additives were preferentially segregated to membrane-coagulant interface during membrane formation. The morphology of membranes was characterized by scanning electron microscopy (SEM). Water contact angle measurements showed that the surface hydrophilicity of PVDF membranes was improved significantly with the increasing of amphiphilic copolymer PVDF-g-PSBMA in cast solution. Protein static adsorption experiment and dynamic fouling resistance experiment revealed that the surface enrichment of PSBMA brush endowed PVDF blend membrane great improvement of surface anti-fouling ability.

  11. Enrichment demand boosts SWU prices

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    The enrichment market is picking up significantly on very brisk demand. US utilities, which normally purchase material nine months to a year ahead of time, are already hitting the market to fill their 1996 requirements. In June, two non-US utilities, one European entity and a US utility bought SWUs, the entity in an off-market deal. But that doesn't tell the whole story. Three other US utilities entered the market during the month. Meanwhile, we count 13 more utilities getting ready to hit the market for more than 4 million SWUs. Why the surge in demand? Utilities, uncertain of the role to be played by the new US Enrichment Corp. and seeking to take advantage of low interest rates, are implementing buy and hold strategies. As a result, the upper end of NUKEM's SWU price range inched up to $78. The lower end dipped to $67 based on the European deal

  12. Enrichment techniques employed in phosphoproteomics

    Czech Academy of Sciences Publication Activity Database

    Fíla, Jan; Honys, David

    2012-01-01

    Roč. 43, č. 3 (2012), s. 1025-1047 ISSN 0939-4451 R&D Projects: GA ČR(CZ) GAP501/11/1462; GA ČR GA522/09/0858; GA ČR GA525/09/0994; GA MŠk OC08011 Institutional research plan: CEZ:AV0Z50380511 Keywords : Phosphoproteomics * Enrichment * IMAC Subject RIV: ED - Physiology Impact factor: 3.914, year: 2012

  13. Uranium enrichment plans and policies

    International Nuclear Information System (INIS)

    Schwennesen, J.L.

    1981-01-01

    Significant progress has been made in US efforts to expand its enrichment capacity. The Cascade Improvement Program (CIP) and Cascade Upgrading Program (CUP) are now complete at Oak Ridge and Paducah and almost complete at Portsmouth. Considerable progress has also been made in constructing the Gas Centrifuge Enrichment Plant (GCEP), and physical construction of the first process building is well under way. Current plans are to have two process buildings on-line by 1989 with the remaining six buildings to be added sequentially as needed to meet demand. The status of DOE enrichment services contracts is essentially unchanged from that reported at last year's seminar. The OUEA latest forecast of nuclear power growth, however, is considerably lower than reported last year, although a leveling trend is becoming apparent. The Variable Tails Assay Option (VTAO) of the AFC contract was made available for the third time for FY 1983. The DOE inventories of natural uranium still remain high. The Department of Energy will dispose of this material by using it for Government programs and for enrichment plant operations. It appears that Government inventories of uranium are adequate through at least the mid-1990s. It remains DOE policy not to dispose of its natural uranium stocks through direct sales in the marketplace, except for very small quantities or if an emergency situation would exist and all reasonable attempts had been made, without success, to obtain natural uranium from commercial sources. Finally, with regard to DOE plans on future transaction tails assays, it still appears likely that the current 0.20 percent uranium-235 reference tails assay will be maintained until well into the 1990s, at which time it might be increased up to 0.25 percent uranium-235

  14. Selenium Enrichment of Horticultural Crops.

    Science.gov (United States)

    Puccinelli, Martina; Malorgio, Fernando; Pezzarossa, Beatrice

    2017-06-04

    The ability of some crops to accumulate selenium (Se) is crucial for human nutrition and health. Selenium has been identified as a cofactor of the enzyme glutathione peroxidase, which is a catalyzer in the reduction of peroxides that can damage cells and tissues, and can act as an antioxidant. Plants are the first link in the food chain, which ends with humans. Increasing the Se quantity in plant products, including leafy and fruity vegetables, and fruit crops, without exceeding the toxic threshold, is thus a good way to increase animal and human Se intake, with positive effects on long-term health. In many Se-enriched plants, most Se is in its major organic form. Given that this form is more available to humans and more efficient in increasing the selenium content than inorganic forms, the consumption of Se-enriched plants appears to be beneficial. An antioxidant effect of Se has been detected in Se-enriched vegetables and fruit crops due to an improved antioxidative status and to a reduced biosynthesis of ethylene, which is the hormone with a primary role in plant senescence and fruit ripening. This thus highlights the possible positive effect of Se in preserving a longer shelf-life and longer-lasting quality.

  15. Selenium Enrichment of Horticultural Crops

    Directory of Open Access Journals (Sweden)

    Martina Puccinelli

    2017-06-01

    Full Text Available The ability of some crops to accumulate selenium (Se is crucial for human nutrition and health. Selenium has been identified as a cofactor of the enzyme glutathione peroxidase, which is a catalyzer in the reduction of peroxides that can damage cells and tissues, and can act as an antioxidant. Plants are the first link in the food chain, which ends with humans. Increasing the Se quantity in plant products, including leafy and fruity vegetables, and fruit crops, without exceeding the toxic threshold, is thus a good way to increase animal and human Se intake, with positive effects on long-term health. In many Se-enriched plants, most Se is in its major organic form. Given that this form is more available to humans and more efficient in increasing the selenium content than inorganic forms, the consumption of Se-enriched plants appears to be beneficial. An antioxidant effect of Se has been detected in Se-enriched vegetables and fruit crops due to an improved antioxidative status and to a reduced biosynthesis of ethylene, which is the hormone with a primary role in plant senescence and fruit ripening. This thus highlights the possible positive effect of Se in preserving a longer shelf-life and longer-lasting quality.

  16. Modeling study on nuclide transport in ocean - an ocean compartment method

    International Nuclear Information System (INIS)

    Lee, Youn Myoung; Suh, Kyung Suk; Han, Kyoung Won

    1991-01-01

    An ocean compartment model simulating transport of nuclides by advection due to ocean circulation and interaction with suspended sediments is developed, by which concentration breakthrough curves of nuclides can be calculated as a function of time. Dividing ocean into arbitrary number of characteristic compartments and performing a balance of mass of nuclides in each ocean compartment, the governing equation for the concentration in the ocean is obtained and a solution by the numerical integration is obtained. The integration method is specially useful for general stiff systems. For transfer coefficients describing advective transport between adjacent compartments by ocean circulation, the ocean turnover time is calculated by a two-dimensional numerical ocean method. To exemplify the compartment model, a reference case calculation for breakthrough curves of three nuclides in low-level radioactive wastes, Tc-99, Cs-137, and Pu-238 released from hypothetical repository under the seabed is carried out with five ocean compartments. Sensitivity analysis studies for some parameters to the concentration breakthrough curves are also made, which indicates that parameters such as ocean turnover time and ocean water volume of compartments have an important effect on the breakthrough curves. (Author)

  17. The isotopic enrichment of uranium in 1979

    International Nuclear Information System (INIS)

    Baron, M.

    1979-01-01

    The Eurodif uranium enrichment plant built on the Tricastin site is described. The uranium isotope separation plants in service abroad are presented. The main characteristics of the international enrichment market are defined [fr

  18. Uranium enrichment (a strategy analysis overview)

    International Nuclear Information System (INIS)

    Blahnik, C.

    1979-08-01

    An analysis of available information on enrichment technology, separative work supply and demand, and SWU cost is presented. Estimates of present and future enrichment costs are provided for use in strategy analyses of alternate nuclear fuel cycles and systems. (auth)

  19. Curriculum enrichment through indigenous Zulu games | Roux ...

    African Journals Online (AJOL)

    Curriculum enrichment through indigenous Zulu games. ... 1997). The aim of the study was to document and analyze indigenous Zulu games for possible curriculum enrichment of physical ... AJOL African Journals Online. HOW TO USE AJOL.

  20. [Orbital compartment syndrome. The most frequent cause of blindness following facial trauma].

    Science.gov (United States)

    Klenk, Gusztáv; Katona, József; Kenderfi, Gábor; Lestyán, János; Gombos, Katalin; Hirschberg, Andor

    2017-09-01

    Although orbital compartment syndrome is a rare condition, it is still the most common cause of blindness following simple or complicated facial fractures. Its pathomechanism is similar to the compartment syndrome in the limb. Little extra fluid (blood, oedema, brain, foreign body) in a non-space yielding space results with increasingly higher pressures within a short period of time. Unless urgent surgical intervention is performed the blocked circulation of the central retinal artery will result irreversible ophthalmic nerve damage and blindness. Aim, material and method: A retrospective analysis of ten years, 2007-2017, in our hospital among those patients referred to us with facial-head trauma combined with blindness. 571 patients had fractures involving the orbit. 23 patients become blind from different reasons. The most common cause was orbital compartment syndrome in 17 patients; all had retrobulbar haematomas as well. 6 patients with retrobulbar haematoma did not develop compartment syndrome. Compartment syndrome was found among patient with extensive and minimal fractures such as with large and minimal haematomas. Early lateral canthotomy and decompression saved 7 patients from blindness. We can not predict and do not know why some patients develop orbital compartment syndrome. Compartment syndrome seems independent from fracture mechanism, comminution, dislocation, amount of orbital bleeding. All patients are in potential risk with midface fractures. We have a high suspicion that orbital compartment syndrome has been somehow missed out in the recommended textbooks of our medical universities and in the postgraduate trainings. Thus compartment syndrome is not recognized. Teaching, training and early surgical decompression is the only solution to save the blind eye. Orv Hetil. 2017; 158(36): 1410-1420.