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Sample records for isolated liquid domain

  1. Solution structure of the isolated Pelle death domain.

    Science.gov (United States)

    Moncrieffe, Martin C; Stott, Katherine M; Gay, Nicholas J

    2005-07-18

    The interaction between the death domains (DDs) of Tube and the protein kinase Pelle is an important component of the Toll pathway. Published crystallographic data suggests that the Pelle-Tube DD interface is plastic and implies that in addition to the two predominant Pelle-Tube interfaces, a third interaction is possible. We present the NMR solution structure of the isolated death domain of Pelle and a study of the interaction between the DDs of Pelle and Tube. Our data suggests the solution structure of the isolated Pelle DD is similar to that of Pelle DD in complex with Tube. Additionally, they suggest that the plasticity observed in the crystal structure may not be relevant in the functioning death domain complex.

  2. Topological Luttinger liquids from decorated domain walls

    Science.gov (United States)

    Parker, Daniel E.; Scaffidi, Thomas; Vasseur, Romain

    2018-04-01

    We introduce a systematic construction of a gapless symmetry-protected topological phase in one dimension by "decorating" the domain walls of Luttinger liquids. The resulting strongly interacting phases provide a concrete example of a gapless symmetry-protected topological (gSPT) phase with robust symmetry-protected edge modes. Using boundary conformal field theory arguments, we show that while the bulks of such gSPT phases are identical to conventional Luttinger liquids, their boundary critical behavior is controlled by a different, strongly coupled renormalization group fixed point. Our results are checked against extensive density matrix renormalization group calculations.

  3. Isolation of suberin from birch outer bark and cork using ionic liquids: A new source of macromonomers

    OpenAIRE

    Ferreira, Rui; Garcia, Helga; Sousa, Andreia F.; Freire, Carmen S. R.; Silvestre, Armando J. D.; Rebelo, Luis Paulo N.; Pereira, Cristina Silva

    2013-01-01

    Cholinium hexanoate, a biocompatible and biodegradable ionic liquid, was recently demonstrated to efficiently and selectively extract suberin domains from cork, combining high extraction efficiency with isolation of a partial depolymerised material. In the present paper, we report a comparative study of the characterisation of suberin extracted from birch outer bark and from cork using cholinium hexanoate. It became apparent that both extracted suberin samples showed still a cross-linked natu...

  4. Is the isolated ligand binding domain a good model of the domain in the native receptor?

    Science.gov (United States)

    Deming, Dustin; Cheng, Qing; Jayaraman, Vasanthi

    2003-05-16

    Numerous studies have used the atomic level structure of the isolated ligand binding domain of the glutamate receptor to elucidate the agonist-induced activation and desensitization processes in this group of proteins. However, no study has demonstrated the structural equivalence of the isolated ligand binding fragments and the protein in the native receptor. In this report, using visible absorption spectroscopy we show that the electronic environment of the antagonist 6-cyano-7-nitro-2,3-dihydroxyquinoxaline is identical for the isolated protein and the native glutamate receptors expressed in cells. Our results hence establish that the local structure of the ligand binding site is the same in the two proteins and validate the detailed structure-function relationships that have been developed based on a comparison of the structure of the isolated ligand binding domain and electrophysiological consequences in the native receptor.

  5. Structure of an isolated unglycosylated antibody CH2 domain

    International Nuclear Information System (INIS)

    Prabakaran, Ponraj; Vu, Bang K.; Gan, Jianhua; Feng, Yang; Dimitrov, Dimiter S.; Ji, Xinhua

    2008-01-01

    The crystal structure of an isolated unglycosylated antibody C H 2 domain has been determined at 1.7 Å resolution. The C H 2 (C H 3 for IgM and IgE) domain of an antibody plays an important role in mediating effector functions and preserving antibody stability. It is the only domain in human immunoglobulins (Igs) which is involved in weak interchain protein–protein interactions with another C H 2 domain solely through sugar moieties. The N-linked glycosylation at Asn297 is conserved in mammalian IgGs as well as in homologous regions of other antibody isotypes. To examine the structural details of the C H 2 domain in the absence of glycosylation and other antibody domains, the crystal structure of an isolated unglycosylated antibody γ1 C H 2 domain was determined at 1.7 Å resolution and compared with corresponding C H 2 structures from intact Fc, IgG and Fc receptor complexes. Furthermore, the oligomeric state of the protein in solution was studied using size-exclusion chromatography. The results suggested that the unglycosylated human antibody C H 2 domain is a monomer and that its structure is similar to that found in the intact Fc, IgG and Fc receptor complex structures. However, certain structural variations were observed in the Fc receptor-binding sites. Owing to its small size, stability and non-immunogenic Ig template, the C H 2-domain structure could be useful for the development by protein design of antibody domains exerting effector functions and/or antigen specificity and as a robust scaffold in protein-engineering applications

  6. Domain Structures in Nematic Liquid Crystals on a Polycarbonate Surface

    Directory of Open Access Journals (Sweden)

    Vasily F. Shabanov

    2013-08-01

    Full Text Available Alignment of nematic liquid crystals on polycarbonate films obtained with the use of solvents with different solvations is studied. Domain structures occurring during the growth on the polymer surface against the background of the initial thread-like or schlieren texture are demonstrated. It is established by optical methods that the domains are stable formations visualizing the polymer surface structures. In nematic droplets, the temperature-induced transition from the domain structure with two extinction bands to the structure with four bands is observed. This transition is shown to be caused by reorientation of the nematic director in the liquid crystal volume from the planar alignment to the homeotropic state with the pronounced radial configuration of nematic molecules on the surface. The observed textures are compared with different combinations of the volume LC orientations and the radial distribution of the director field and the disclination lines at the polycarbonate surface.

  7. Dynamics of cylindrical domain walls in smectic C liquid crystals

    International Nuclear Information System (INIS)

    Stewart, I W; Wigham, E J

    2009-01-01

    An analysis of the dynamics of cylindrical domain walls in planar aligned samples of smectic C liquid crystals is presented. A circular magnetic field, induced by an electric current, drives a time-dependent reorientation of the corresponding radially dependent director field. Nonlinear approximations to the relevant nonlinear dynamic equation, derived from smectic continuum theory, are solved in a comoving coordinated frame: exact solutions are found for a π-wall and numerical solutions are calculated for π/2-walls. Each calculation begins with an assumed initial state for the director that is a prescribed cylindrical domain wall. Such an initial wall will proceed to expand or contract as its central core propagates radially inwards or outwards, depending on the boundary conditions for the director, the elastic constants, the magnitude of the field and the sign of the magnetic anisotropy of the liquid crystal

  8. In-plane pitch control of cholesteric liquid crystals by formation of artificial domains via patterned photopolymerization.

    Science.gov (United States)

    Yoshida, Hiroyuki; Miura, Yusuke; Tokuoka, Kazuki; Suzuki, Satoshi; Fujii, Akihiko; Ozaki, Masanori

    2008-11-10

    A controlled helix pitch modulation in the in-plane direction of a planarly aligned cholesteric liquid crystal cell is demonstrated by using photopolymerizable cholesteric liquid crystals. By fabricating artificial domains with a closed volume via two-photon excitation laser-lithography, the degree of pitch modulation could be controlled by adjusting the surface area to volume ratio of the domain. A pitch modulation of over 60 nm was realized by designing the shape of the artificial domain.

  9. Stabilization and isolation of low-level liquid waste disposal sites

    International Nuclear Information System (INIS)

    Phillips, S.J.; Gilbert, T.W.

    1987-01-01

    Rockwell Hanford Operations is developing and testing equipment for stabilization and isolation of low-level radioactive liquid waste disposal sites. Stabilization and isolation are accomplished by a dynamic consolidation and particulate grout injection system. System equipment components include: a mobile grout plant for transport, mixing, and pumping of particulate grout; a vibratory hammer/extractor for consolidation of waste, backfill, and for emplacement of the injector; dynamic consolidation/injector probe for introducing grout into fill material; and an open-void surface injector that uses surface or subsurface mechanical or pneumatic packers and displacement gas filtration for introducing grout into disposal structure access piping. Treatment of a liquid-waste disposal site yields a physically stable, cementitious monolith. Additional testing and modification of this equipment for other applications to liquid waste disposal sites is in progress

  10. Bicontinuous structured liquids with sub-micrometre domains using nanoparticle surfactants

    Science.gov (United States)

    Huang, Caili; Forth, Joe; Wang, Weiyu; Hong, Kunlun; Smith, Gregory S.; Helms, Brett A.; Russell, Thomas P.

    2017-11-01

    Bicontinuous jammed emulsions (or bijels) are tortuous, interconnected structures of two immiscible liquids, kinetically trapped by colloidal particles that are irreversibly bound to the oil-water interface. A wealth of applications has been proposed for bijels in catalysis, energy storage and molecular encapsulation, but large domain sizes (on the order of 5 µm or larger) and difficulty in fabrication pose major barriers to their use. Here, we show that bijels with sub-micrometre domains can be formed via homogenization, rather than spinodal decomposition. We achieve this by using nanoparticle surfactants: polymers and nanoparticles of complementary functionality (for example, ion-pairing) that bind to one another at the oil-water interface. This allows the stabilization of the bijel far from the demixing point of the liquids, with interfacial tensions on the order of 20 mN m-1. Furthermore, our strategy is extremely versatile, as solvent, nanoparticle and ligand can all be varied.

  11. Shape of isolated domains in lithium tantalate single crystals at elevated temperatures

    International Nuclear Information System (INIS)

    Shur, V. Ya.; Akhmatkhanov, A. R.; Baturin, I. S.; Chezganov, D. S.; Lobov, A. I.; Smirnov, M. M.

    2013-01-01

    The shape of isolated domains has been investigated in congruent lithium tantalate (CLT) single crystals at elevated temperatures and analyzed in terms of kinetic approach. The obtained temperature dependence of the growing domain shape in CLT including circular shape at temperatures above 190 °C has been attributed to increase of relative input of isotropic ionic conductivity. The observed nonstop wall motion and independent domain growth after merging in CLT as opposed to stoichiometric lithium tantalate have been attributed to difference in wall orientation. The computer simulation has confirmed applicability of the kinetic approach to the domain shape explanation

  12. Domain-adaptive finite difference methods for collapsing annular liquid jets

    Science.gov (United States)

    Ramos, J. I.

    1993-01-01

    A domain-adaptive technique which maps a time-dependent, curvilinear geometry into a unit square is used to determine the steady state mass absorption rate and the collapse of annular liquid jets. A method of lines is used to solve the one-dimensional fluid dynamics equations written in weak conservation-law form, and upwind differences are employed to evaluate the axial convective fluxes. The unknown, time-dependent, axial location of the downstream boundary is determined from the solution of an ordinary differential equation which is nonlinearly coupled to the fluid dynamics and gas concentration equations. The equation for the gas concentration in the annular liquid jet is written in strong conservation-law form and solved by means of a method of lines at high Peclet numbers and a line Gauss-Seidel method at low Peclet numbers. The effects of the number of grid points along and across the annular jet, time step, and discretization of the radial convective fluxes on both the steady state mass absorption rate and the jet's collapse rate have been analyzed on staggered and non-staggered grids. The steady state mass absorption rate and the collapse of annular liquid jets are determined as a function of the Froude, Peclet and Weber numbers, annular jet's thickness-to-radius ratio at the nozzle exit, initial pressure difference across the annular jet, nozzle exit angle, temperature of the gas enclosed by the annular jet, pressure of the gas surrounding the jet, solubilities at the inner and outer interfaces of the annular jet, and gas concentration at the nozzle exit. It is shown that the steady state mass absorption rate is proportional to the inverse square root of the Peclet number except for low values of this parameter, and that the possible mathematical incompatibilities in the concentration field at the nozzle exit exert a great influence on the steady state mass absorption rate and on the jet collapse. It is also shown that the steady state mass absorption

  13. Non-linear seismic response of base-isolated liquid storage tanks to bi-directional excitation

    International Nuclear Information System (INIS)

    Shrimali, M.K.; Jangid, R.S.

    2002-01-01

    Seismic response of the liquid storage tanks isolated by lead-rubber bearings is investigated for bi-directional earthquake excitation (i.e. two horizontal components). The biaxial force-deformation behaviour of the bearings is considered as bi-linear modelled by coupled non-linear differential equations. The continuous liquid mass of the tank is modelled as lumped masses known as convective mass, impulsive mass and rigid mass. The corresponding stiffness associated with these lumped masses has been worked out depending upon the properties of the tank wall and liquid mass. Since the force-deformation behaviour of the bearings is non-linear, as a result, the seismic response is obtained by the Newmark's step-by-step method. The seismic responses of two types of the isolated tanks (i.e. slender and broad) are investigated under several recorded earthquake ground to study the effects of bi-directional interaction. Further, a parametric study is also carried out to study the effects of important system parameters on the effectiveness of seismic isolation for liquid storage tanks. The various important parameters considered are: (i) the period of isolation, (ii) the damping of isolation bearings and (iii) the yield strength level of the bearings. It has been observed that the seismic response of isolated tank is found to be insensitive to interaction effect of the bearing forces. Further, there exists an optimum value of isolation damping for which the base shear in the tank attains the minimum value. Therefore, increasing the bearing damping beyond a certain value may decrease the bearing and sloshing displacements but it may increase the base shear

  14. Electrostatic force microscopy and electrical isolation of etched few-layer graphene nano-domains

    Energy Technology Data Exchange (ETDEWEB)

    Hunley, D. Patrick; Sundararajan, Abhishek; Boland, Mathias J.; Strachan, Douglas R., E-mail: doug.strachan@uky.edu [Department of Physics and Astronomy, University of Kentucky, Lexington, Kentucky 40506 (United States)

    2014-12-15

    Nanostructured bi-layer graphene samples formed through catalytic etching are investigated with electrostatic force microscopy. The measurements and supporting computations show a variation in the microscopy signal for different nano-domains that are indicative of changes in capacitive coupling related to their small sizes. Abrupt capacitance variations detected across etch tracks indicates that the nano-domains have strong electrical isolation between them. Comparison of the measurements to a resistor-capacitor model indicates that the resistance between two bi-layer graphene regions separated by an approximately 10 nm wide etch track is greater than about 1×10{sup 12} Ω with a corresponding gap resistivity greater than about 3×10{sup 14} Ω⋅nm. This extremely large gap resistivity suggests that catalytic etch tracks within few-layer graphene samples are sufficient for providing electrical isolation between separate nano-domains that could permit their use in constructing atomically thin nanogap electrodes, interconnects, and nanoribbons.

  15. Electrostatic force microscopy and electrical isolation of etched few-layer graphene nano-domains

    International Nuclear Information System (INIS)

    Hunley, D. Patrick; Sundararajan, Abhishek; Boland, Mathias J.; Strachan, Douglas R.

    2014-01-01

    Nanostructured bi-layer graphene samples formed through catalytic etching are investigated with electrostatic force microscopy. The measurements and supporting computations show a variation in the microscopy signal for different nano-domains that are indicative of changes in capacitive coupling related to their small sizes. Abrupt capacitance variations detected across etch tracks indicates that the nano-domains have strong electrical isolation between them. Comparison of the measurements to a resistor-capacitor model indicates that the resistance between two bi-layer graphene regions separated by an approximately 10 nm wide etch track is greater than about 1×10 12  Ω with a corresponding gap resistivity greater than about 3×10 14  Ω⋅nm. This extremely large gap resistivity suggests that catalytic etch tracks within few-layer graphene samples are sufficient for providing electrical isolation between separate nano-domains that could permit their use in constructing atomically thin nanogap electrodes, interconnects, and nanoribbons

  16. Isolating silkworm genomic DNA without liquid nitrogen suitable for ...

    African Journals Online (AJOL)

    Genomic DNA was isolated from posterior silk gland of silkworms, Antheraea assama. Absolute alcohol was used as tissue fixing solution instead of grinding in liquid nitrogen, which yielded high molecular weight DNA (>40 kb). Samples yielded similar amount of DNA when fixed in absolute alcohol (400 μmg/g of silk gland ...

  17. Detection of Ionic liquid using terahertz time-domain spectroscopy

    Science.gov (United States)

    Wang, Cuicui; Zhao, Xiaojing; Liu, Shangjian; Zuo, Jian; Zhang, Cunlin

    2018-01-01

    Terahertz (THz, THz+1012Hz) spectroscopy is a far-infrared analytical technology with spectral bands locating between microware and infrared ranges. Being of excellent transmission, non-destruction and high discrimination, this technology has been applied in various fields such as physics, chemistry, nondestructive detection, communication, biomedicine public security. Terahertz spectrum is corresponding with vibration and rotation of liquid molecules, which is suitable to identify and study the liquid molecular dynamics. It is as a powerful spectral detection technology, terahertz time-domain spectroscopy is widely used in solution detection. can enable us to extract the material parameters or dielectric spectrum that show material micro-structure and dynamics by measuring amplitude and phase from coherent terahertz pulses. Ionic liquid exists in most biological tissues, and it is very important for life. It has recently been suggested that near-fired terahertz ionic contrast microscopy can be employed to image subtle changes in ionic concentrations arising from neuronal activity. In this paper, we detected Ionic liquid with different concentrations at room temperature by THz-TDS technique in the range of 0.2-1.5 THz. The liquid cell with a thickness of 0.2mm is made of quartz. The absorption coefficient, refractive index and dielectric function of solutions can be extracted based on THz-TDS. We use an expanded model for fitting the dielectric function based on a combination of a Debye relation for the anions and cations. We find A linear increase of the real and imaginary part of the dielectric function compared with pure water with increasing ion concentrations. A good agreement between the model and the experimental results is obtained. By means of dielectric relaxation process, it was found that the characteristic time of molecular movement and the information related to the liquid molecular structure and movement was obtained.

  18. Non liquid nitrogen-based-method for isolation of DNA from ...

    African Journals Online (AJOL)

    A simple, efficient, reliable and cost-effective method for isolation of total genomic DNA from fungi, suitable for polymerase chain reaction (PCR) amplification and other molecular applications was described. The main advantages of the method are: (1) does not require the use of liquid nitrogen for preparation of fungi DNA; ...

  19. Testing of seismic isolation bearings for advanced liquid metal reactor prism

    International Nuclear Information System (INIS)

    Tajirian, F.F.; Kelly, J.M.

    1988-01-01

    Seismic isolation can significantly mitigate earthquake loads on liquid metal reactors (LMR), thus reducing the impact of seismic loads on design. This improves plant safety margins for beyond-design basis seismic events and enhances adaptability of a standardized design to a variety of sites, with potential cost benefits. The PRISM (Power Reactor Inherently Safe Module) LMR incorporates a horizontal isolation system which consists of high damping steel laminated rubber bearings. The results of an experimental program to determine the mechanical properties of the rubber compound and the bearing performance under different loading conditions are presented. The test results demonstrate the excellent performance of the bearings and their suitability for isolating compact LMR plants

  20. Reverse-mode thermoresponsive light attenuators produced by optical anisotropic composites of nematic liquid crystals and reactive mesogens

    Science.gov (United States)

    Kakiuchida, Hiroshi; Ogiwara, Akifumi

    2018-04-01

    Polymer network liquid crystals (PNLCs) whose optical transmittance state switches between transparence at low temperatures and haze at high temperatures were fabricated from mixtures of nematic liquid crystals (LCs) and reactive mesogens (RMs). This PNLC structure is simple but effective, namely, consists of micro-scale domains of orientation-ordered LCs and anisotropically polymerized RMs. The domains form through photopolymerization induced phase separation with inhomogeneous irradiation projected by laser speckling techniques. This irradiation method enables you to control the size and shape of phase-separation domains, and these PNLCs can be applied to novel thermoresponsive optical devices; optical isolators, thermometric sheets, and smart windows.

  1. Fault Detection, Isolation and Recovery (FDIR) Portable Liquid Oxygen Hardware Demonstrator

    Science.gov (United States)

    Oostdyk, Rebecca L.; Perotti, Jose M.

    2011-01-01

    The Fault Detection, Isolation and Recovery (FDIR) hardware demonstration will highlight the effort being conducted by Constellation's Ground Operations (GO) to provide the Launch Control System (LCS) with system-level health management during vehicle processing and countdown activities. A proof-of-concept demonstration of the FDIR prototype established the capability of the software to provide real-time fault detection and isolation using generated Liquid Hydrogen data. The FDIR portable testbed unit (presented here) aims to enhance FDIR by providing a dynamic simulation of Constellation subsystems that feed the FDIR software live data based on Liquid Oxygen system properties. The LO2 cryogenic ground system has key properties that are analogous to the properties of an electronic circuit. The LO2 system is modeled using electrical components and an equivalent circuit is designed on a printed circuit board to simulate the live data. The portable testbed is also be equipped with data acquisition and communication hardware to relay the measurements to the FDIR application running on a PC. This portable testbed is an ideal capability to perform FDIR software testing, troubleshooting, training among others.

  2. Shapes of isolated domains and field induced evolution of regular and random 2D domain structures in LiNbO3 and LiTaO3

    International Nuclear Information System (INIS)

    Chernykh, A.; Shur, V.; Nikolaeva, E.; Shishkin, E.; Shur, A.; Terabe, K.; Kurimura, S.; Kitamura, K.; Gallo, K.

    2005-01-01

    The variety of the shapes of isolated domains, revealed in congruent and stoichiometric LiTaO 3 and LiNbO 3 by chemical etching and visualized by optical and scanning probe microscopy, was obtained by computer simulation. The kinetic nature of the domain shape was clearly demonstrated. The kinetics of domain structure with the dominance of the growth of the steps formed at the domain walls as a result of domain merging was investigated experimentally in slightly distorted artificial regular two-dimensional (2D) hexagonal domain structure and random natural one. The artificial structure has been realized in congruent LiNbO 3 by 2D electrode pattern produced by photolithography. The polarization reversal in congruent LiTaO 3 was investigated as an example of natural domain growth limited by merging. The switching process defined by domain merging was studied by computer simulation. The crucial dependence of the switching kinetics on the nuclei concentration has been revealed

  3. Electromagnetic numerical characterization of the laser-induced liquid crystal lens by finite-difference time domain method

    International Nuclear Information System (INIS)

    Morisaki, T.; Ono, H.

    2005-01-01

    A laser-induced liquid-crystal lens is formed by large optical non-linearity and anisotropic complex refractive indices in guest-host liquid crystals. We obtained light wave propagation characteristics of the laser-induced LC lens. Three analytical methods were used to obtain light wave propagation characteristics. Analysis by 3-dimensional heat conduction was applied to determine the refractive index in the liquid-crystal layer. Another method used was to determine light wave propagation characteristics in the laser-induced lens by means of the finite-difference tune domain (FDTD) method and diffraction theory. In this study, we draw a parallel between the experimental results and FDTD. Copyright (2003) AD-TECH - International Foundation for the Advancement of Technology Ltd

  4. Rescue of HIV-1 release by targeting widely divergent NEDD4-type ubiquitin ligases and isolated catalytic HECT domains to Gag.

    Directory of Open Access Journals (Sweden)

    Eric R Weiss

    2010-09-01

    Full Text Available Retroviruses engage the ESCRT pathway through late assembly (L domains in Gag to promote virus release. HIV-1 uses a PTAP motif as its primary L domain, which interacts with the ESCRT-I component Tsg101. In contrast, certain other retroviruses primarily use PPxY-type L domains, which constitute ligands for NEDD4-type ubiquitin ligases. Surprisingly, although HIV-1 Gag lacks PPxY motifs, the release of HIV-1 L domain mutants is potently enhanced by ectopic NEDD4-2s, a native isoform with a naturally truncated C2 domain that appears to account for the residual titer of L domain-defective HIV-1. The reason for the unique potency of the NEDD4-2s isoform has remained unclear. We now show that the naturally truncated C2 domain of NEDD4-2s functions as an autonomous Gag-targeting module that can be functionally replaced by the unrelated Gag-binding protein cyclophilin A (CypA. The residual C2 domain of NEDD4-2s was sufficient to transfer the ability to stimulate HIV-1 budding to other NEDD4 family members, including the yeast homologue Rsp5, and even to isolated catalytic HECT domains. The isolated catalytic domain of NEDD4-2s also efficiently promoted HIV-1 budding when targeted to Gag via CypA. We conclude that the regions typically required for substrate recognition by HECT ubiquitin ligases are all dispensable to stimulate HIV-1 release, implying that the relevant target for ubiquitination is Gag itself or can be recognized by divergent isolated HECT domains. However, the mere ability to ubiquitinate Gag was not sufficient to stimulate HIV-1 budding. Rather, our results indicate that the synthesis of K63-linked ubiquitin chains is critical for ubiquitin ligase-mediated virus release.

  5. Ionic-liquid-based ultrasound-assisted extraction of isoflavones from Belamcanda chinensis and subsequent screening and isolation of potential α-glucosidase inhibitors by ultrafiltration and semipreparative high-performance liquid chromatography.

    Science.gov (United States)

    Li, Senlin; Li, Sainan; Huang, Yu; Liu, Chunming; Chen, Lina; Zhang, Yuchi

    2017-06-01

    The separation of a compound of interest from its structurally similar homologues to produce high-purity natural products is a challenging problem. This work proposes a novel method for the separation of iristectorigenin A from its structurally similar homologues by ionic-liquid-based ultrasound-assisted extraction and the subsequent screening and isolation of potential α-glucosidase inhibitors via ultrafiltration and semipreparative high-performance liquid chromatography. Ionic-liquid-based ultrasound-assisted extraction was successfully applied to the extraction of tectorigenin, iristectorigenin A, irigenin, and irisflorentin from Belamcanda chinensis. The optimum conditions for the efficient extraction of isoflavones were determined as 1.0 M 1-ethyl-3-methylimidazolium tetrafluoroborate with extraction time of 30 min and a solvent to solid ratio of 30 mL/g. Ultrafiltration with liquid chromatography and mass spectrometry was applied to screen and identify α-glucosidase inhibitors from B. chinensis, followed by the application of semipreparative high-performance liquid chromatography to separate and isolate the active constituents. Four major compounds including tectorigenin, iristectorigenin A, irigenin, and irisflorentin were screened and identified as α-glucosidase inhibitors, and then the four active compounds abovementioned were subsequently isolated by semipreparative high-performance liquid chromatography (99.89, 88.97, 99.79, and 99.97% purity, respectively). The results demonstrate that ionic liquid extraction can be successfully applied to the extraction of isoflavones from B. chinensis. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Soy protein isolate inhibits hepatic tumor promotion in mice fed a high-fat liquid diet.

    Science.gov (United States)

    Mercer, Kelly E; Pulliam, Casey F; Pedersen, Kim B; Hennings, Leah; Ronis, Martin Jj

    2017-03-01

    Alcoholic and nonalcoholic fatty liver diseases are risk factors for development of hepatocellular carcinoma, but the underlying mechanisms are poorly understood. On the other hand, ingestion of soy-containing diets may oppose the development of certain cancers. We previously reported that replacing casein with a soy protein isolate reduced tumor promotion in the livers of mice with alcoholic liver disease after feeding a high fat ethanol liquid diet following initiation with diethylnitrosamine. Feeding soy protein isolate inhibited processes that may contribute to tumor promotion including inflammation, sphingolipid signaling, and Wnt/β-catenin signaling. We have extended these studies to characterize liver tumor promotion in a model of nonalcoholic fatty liver disease produced by chronic feeding of high-fat liquid diets in the absence of ethanol. Mice treated with diethylnitrosamine on postnatal day 14 were fed a high-fat liquid diet made with casein or SPI as the sole protein source for 16 weeks in adulthood. Relative to mice fed normal chow, a high fat/casein diet led to increased tumor promotion, hepatocyte proliferation, steatosis, and inflammation. Replacing casein with soy protein isolate counteracted these effects. The high fat diets also resulted in a general increase in transcripts for Wnt/β-catenin pathway components, which may be an important mechanism, whereby hepatic tumorigenesis is promoted. However, soy protein isolate did not block Wnt signaling in this nonalcoholic fatty liver disease model. We conclude that replacing casein with soy protein isolate blocks development of steatosis, inflammation, and tumor promotion in diethylnitrosamine-treated mice fed high fat diets. Impact statement The impact of dietary components on cancer is a topic of great interest for both the general public and the scientific community. Liver cancer is currently the second leading form of cancer deaths worldwide. Our study has addressed the effect of the protein

  7. The corkscrew instability of a Freedericksz domain wall in a nematic liquid crystal

    CERN Document Server

    Munoz, A D L; Müller, M; Schoepf, W; Rehberg, I

    2003-01-01

    A liquid crystal with slightly positive dielectric anisotropy is investigated in the planar configuration. This system allows for competition between electroconvection and the homogeneous Freedericksz transition, leading to a rather complicated bifurcation scenario. We report measurements of a novel instability leading to the 'corkscrew' pattern. This state is closely connected to the Freedericksz state as it manifests itself as a regular modulation along a Freedericksz domain wall, although its frequency dependence indicates that electroconvection must play a crucial role. It can be understood in terms of a pitchfork bifurcation from a straight domain wall. Quantitative characterization is performed in terms of amplitude, wavelength and relaxation time. Its wavelength is of the order of the probe thickness, while its ondulation amplitude is an order of magnitude smaller. The relaxation time is comparable to the one obtained for electroconvection.

  8. NMR investigation of the isolated second voltage-sensing domain of human Nav1.4 channel.

    Science.gov (United States)

    Paramonov, A S; Lyukmanova, E N; Myshkin, M Yu; Shulepko, M A; Kulbatskii, D S; Petrosian, N S; Chugunov, A O; Dolgikh, D A; Kirpichnikov, M P; Arseniev, A S; Shenkarev, Z O

    2017-03-01

    Voltage-gated Na + channels are essential for the functioning of cardiovascular, muscular, and nervous systems. The α-subunit of eukaryotic Na + channel consists of ~2000 amino acid residues and encloses 24 transmembrane (TM) helices, which form five membrane domains: four voltage-sensing (VSD) and one pore domain. The structural complexity significantly impedes recombinant production and structural studies of full-sized Na + channels. Modular organization of voltage-gated channels gives an idea for studying of the isolated second VSD of human skeletal muscle Nav1.4 channel (VSD-II). Several variants of VSD-II (~150a.a., four TM helices) with different N- and C-termini were produced by cell-free expression. Screening of membrane mimetics revealed low stability of VSD-II samples in media containing phospholipids (bicelles, nanodiscs) associated with the aggregation of electrically neutral domain molecules. The almost complete resonance assignment of 13 C, 15 N-labeled VSD-II was obtained in LPPG micelles. The secondary structure of VSD-II showed similarity with the structures of bacterial Na + channels. The fragment of S4 TM helix between the first and second conserved Arg residues probably adopts 3 10 -helical conformation. Water accessibility of S3 helix, observed by the Mn 2+ titration, pointed to the formation of water-filled crevices in the micelle embedded VSD-II. 15 N relaxation data revealed characteristic pattern of μs-ms time scale motions in the VSD-II regions sharing expected interhelical contacts. VSD-II demonstrated enhanced mobility at ps-ns time scale as compared to isolated VSDs of K + channels. These results validate structural studies of isolated VSDs of Na + channels and show possible pitfalls in application of this 'divide and conquer' approach. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Oscillation of an isolated liquid plug inside a dry capillary

    Science.gov (United States)

    Srinivasan, Vyas; Kumar, Siddhartha; Asfer, Mohammed; Khandekar, Sameer

    2017-11-01

    The present work reports an experimental study on the dynamics of partially wetting isolated liquid plug (DI water), which is made to oscillate inside a square, glass capillary tube (1 mm × 1 mm; 60 mm length). The liquid plug is made to oscillate pneumatically at two different frequencies (0.25 and 0.35 Hz), using a cam-follower mechanism. Bright field imaging is used to visualize the three-phase contact line behavior, while, micro-Particle Imaging Velocimetry (PIV) apparatus is used to discern the nature of flow inside the oscillating liquid plug. During a cycle, due to the partial wetting nature of DI water, the three-phase contact line at the menisci gets pinned at the extreme end of each stroke, where the dynamic apparent contact angle gets drastically altered before the initiation of the next stroke. The difference between the apparent contact angle of the front and rear meniscus are seen to be a function of the oscillating frequency; the difference increasing with increasing frequency. The flow inside the liquid plug reveals unique non-Poiseuille flow features near the meniscus, due to free-slip boundary condition, which leads to formation of distinct vortex pairs behind it. The vortices too change their direction during each stroke of the oscillation, eventually leading to an alternating recirculation pattern inside the plug. The results clearly indicate that improved mathematical models are required for predicting transport parameters in such flows, which are important in engineering systems such as pulsating heat pipes, lab-on-chip devices and PEM fuel cells.

  10. Chiral domain formation from the mixture of achiral rod-like liquid crystal and tri boomerang-shaped molecule

    Science.gov (United States)

    Lee, Ji-Hoon; Yoon, Tae-Hoon

    2013-08-01

    Spontaneous formation of chiral domains such as a helical filament and a bent-broom texture was observed from the mixture of a rod-like liquid crystal octylcyano-biphenyl (8CB) and a tri boomerang-shaped 2,4,6-triphenoxy-1,3,5-triazine (triphenoxy) molecule. Although the constituent molecules were achiral, their mixture showed the chiral domains with the equal fraction of the opposite handedness. No tilt of 8CB molecules in the smectic layer was observed, implying the chirality is not due to the polar packing and tilt of the molecules. In addition, the splay and bend elastic constant of 8CB was decreased after doping triphenoxy. A structural conformation of triphenoxy and an orientational coupling between 8CB and triphenoxy are considered to be related to the chiral domain formation.

  11. Seismic isolation development for the US advanced liquid-metal reactor program

    International Nuclear Information System (INIS)

    Gluekler, E.L.; Bigelow, C.C.; DeVita, V.; Kelly, J.M.; Seidensticker, R.W.; Tajirian, F.F.

    1989-01-01

    GE Nuclear Energy, in association with a US Industrial Team and support from the US National Laboratories and Universities, is developing a modular liquid-metal reactor concept for the US Department of Energy (DOE). The objective of this development is to provide, by the turn of the century, a reactor concept with optimized passive safety features that is economically competitive with other domestic energy sources, licensable, and ready for commercial deployment. One of the unique features of the concept is the seismic isolation of the reactor modules which decouples the reactor and their safety systems from potentially damaging ground motions and significantly enhances the structural resistance to high energy, as well as long duration earthquakes. Seismic isolation is accomplished with high damping natural rubber bearings. The reactors are located in individual silos below grade level and are supported by the isolator bearings at approximately their center of gravity. This application of seismic isolation is the first for a US nuclear power plant. A development program has been established to assure the full benefits from the utilization of this new approach and to provide adequate system characterization and qualification for licensing certification. The development program is described in this paper and selected results are presented. The initial testing indicated excellent performance of high damping natural rubber bearings

  12. Seismic isolation development for the US advanced liquid-metal reactor program

    International Nuclear Information System (INIS)

    Gluekler, E.L.; Bigelow, C.C.; DeVita, V.; Kelly, J.M.; Seidensticker, R.W.; Tajirian, F.F.

    1991-01-01

    GE Nuclear Energy, in association with a US Industrial Team and support from the US National Laboratories and Universities, is developing a modular liquid-metal reactor concept for the US DOE. The objective of this development is to provide, by the turn of the century, a reactor with optimized passive safety features that is economically competitive with other domestic energy sources, licensable, and ready for commercial deployment. One of the unique features of the concept is the seismic isolation of the reactor modules which decouples the reactors and their safety systems from potentially damaging ground motions and significantly enhances the structural resistance to high energy, as well as long-duration earthquakes. Seismic isolation is accomplished with high-damping natural-rubber bearings. The reactors are located in individual silos below grade level and are supported by the isolator bearings at approximately their center of gravity. This application of seismic isolation is the first for a US nuclear power plant. A development program has been established to assure the full benefits from the utilization of this new approach and to provide adequate system characterization and qualification for licensing certification. The development program, which is supported by the US DOE, ANL, Energy Technology Engineering Center (ETEC), the University of California at Berkeley (UC-Berkeley), GE, and Bechtel National, Inc. (BNI), is described and selected results are presented. The initial testing indicated excellent performance of high-damping natural-rubber bearings. The development of seismic isolation guidelines is in progress as a joint activity between ENEA of Italy and the GE Team. (orig./HP)

  13. Ultrasound-based measurement of liquid-layer thickness: A novel time-domain approach

    Science.gov (United States)

    Praher, Bernhard; Steinbichler, Georg

    2017-01-01

    Measuring the thickness of a thin liquid layer between two solid materials is important when the adequate separation of metallic parts by a lubricant film (e.g., in bearings or mechanical seals) is to be assessed. The challenge in using ultrasound-based systems for such measurements is that the signal from the liquid layer is a superposition of multiple reflections. We have developed an algorithm for reconstructing this superimposed signal in the time domain. By comparing simulated and measured signals, the time-of-flight of the ultrasonic pulse in a layer can be estimated. With the longitudinal sound velocity known, the layer thickness can then be calculated. In laboratory measurements, we validate successfully (maximum relative error 4.9%) our algorithm for layer thicknesses ranging from 30 μm to 200 μm. Furthermore, we tested our method in the high-temperature environment of polymer processing by measuring the clearance between screw and barrel in the plasticisation unit of an injection moulding machine. The results of such measurements can indicate (i) the wear status of the tribo-mechanical screw-barrel system and (ii) unsuitable process conditions.

  14. Coupling compositional liquid gas Darcy and free gas flows at porous and free-flow domains interface

    Energy Technology Data Exchange (ETDEWEB)

    Masson, R., E-mail: roland.masson@unice.fr [LJAD, University Nice Sophia Antipolis, CNRS UMR 7351 (France); Team COFFEE INRIA Sophia Antipolis Méditerranée (France); Trenty, L., E-mail: laurent.trenty@andra.fr [Andra, Chatenay Malabry (France); Zhang, Y., E-mail: yumeng.zhang@unice.fr [LJAD, University Nice Sophia Antipolis, CNRS UMR 7351 (France); Team COFFEE INRIA Sophia Antipolis Méditerranée (France)

    2016-09-15

    This paper proposes an efficient splitting algorithm to solve coupled liquid gas Darcy and free gas flows at the interface between a porous medium and a free-flow domain. This model is compared to the reduced model introduced in [6] using a 1D approximation of the gas free flow. For that purpose, the gas molar fraction diffusive flux at the interface in the free-flow domain is approximated by a two point flux approximation based on a low-frequency diagonal approximation of a Steklov–Poincaré type operator. The splitting algorithm and the reduced model are applied in particular to the modelling of the mass exchanges at the interface between the storage and the ventilation galleries in radioactive waste deposits.

  15. Blind detection of isolated astrophysical pulses in the spatial Fourier transform domain

    Science.gov (United States)

    Schmid, Natalia A.; Prestage, Richard M.

    2018-04-01

    We present a novel approach for the detection of isolated transients in pulsar surveys and fast radio transient observations. Rather than the conventional approach of performing a computationally expensive blind DM search, we take the spatial Fourier transform (SFT) of short (˜ few seconds) sections of data. A transient will have a characteristic signature in the SFT domain, and we present a blind statistic which may be used to detect this signature at an empirical zero False Alarm Rate (FAR). The method has been evaluated using simulations, and also applied to two fast radio burst observations. In addition to its use for current observations, we expect this method will be extremely beneficial for future multi-beam observations made by telescopes equipped with phased array feeds.

  16. Model-Based Fault Detection and Isolation of a Liquid-Cooled Frequency Converter on a Wind Turbine

    DEFF Research Database (Denmark)

    Li, Peng; Odgaard, Peter Fogh; Stoustrup, Jakob

    2012-01-01

    advanced fault detection and isolation schemes. In this paper, an observer-based fault detection and isolation method for the cooling system in a liquid-cooled frequency converter on a wind turbine which is built up in a scalar version in the laboratory is presented. A dynamic model of the scale cooling...... system is derived based on energy balance equation. A fault analysis is conducted to determine the severity and occurrence rate of possible component faults and their end effects in the cooling system. A method using unknown input observer is developed in order to detect and isolate the faults based...... on the developed dynamical model. The designed fault detection and isolation algorithm is applied on a set of measured experiment data in which different faults are artificially introduced to the scaled cooling system. The experimental results conclude that the different faults are successfully detected...

  17. Isolation of αL I domain mutants mediating firm cell adhesion using a novel flow-based sorting method.

    Science.gov (United States)

    Pepper, Lauren R; Parthasarathy, Ranganath; Robbins, Gregory P; Dang, Nicholas N; Hammer, Daniel A; Boder, Eric T

    2013-08-01

    The inserted (I) domain of αLβ2 integrin (LFA-1) contains the entire binding site of the molecule. It mediates both rolling and firm adhesion of leukocytes at sites of inflammation depending on the activation state of the integrin. The affinity change of the entire integrin can be mimicked by the I domain alone through mutations that affect the conformation of the molecule. High-affinity mutants of the I domain have been discovered previously using both rational design and directed evolution. We have found that binding affinity fails to dictate the behavior of I domain adhesion under shear flow. In order to better understand I domain adhesion, we have developed a novel panning method to separate yeast expressing a library of I domain variants on the surface by adhesion under flow. Using conditions analogous to those experienced by cells interacting with the post-capillary vascular endothelium, we have identified mutations supporting firm adhesion that are not found using typical directed evolution techniques that select for tight binding to soluble ligands. Mutants isolated using this method do not cluster with those found by sorting with soluble ligand. Furthermore, these mutants mediate shear-driven cell rolling dynamics decorrelated from binding affinity, as previously observed for I domains bearing engineered disulfide bridges to stabilize activated conformational states. Characterization of these mutants supports a greater understanding of the structure-function relationship of the αL I domain, and of the relationship between applied force and bioadhesion in a broader context.

  18. A new mechanism to render clinical isolates of Escherichia coli non-susceptible to imipenem: substitutions in the PBP2 penicillin-binding domain.

    Science.gov (United States)

    Aissa, Nejla; Mayer, Noémie; Bert, Fréderic; Labia, Roger; Lozniewski, Alain; Nicolas-Chanoine, Marie-Hélène

    2016-01-01

    So far, two types of mechanism are known to be involved in carbapenem non-susceptibility of Escherichia coli clinical isolates: reduced outer membrane permeability associated with production of ESBLs and/or overproduction of class C β-lactamases; and production of carbapenemases. Non-susceptibility to only imipenem observed in two clinical isolates suggested a new mechanism, described in the present study. The ST was determined for the two isolates of E. coli (strains LSNy and VSBj), and their chromosomal region encoding the penicillin-binding domain of PBP2 was amplified, sequenced and then used for recombination experiments in E. coli K12 C600. Antibiotic MICs were determined using the Etest method. Strains LSNy and VSBj, which displayed ST23 and ST345, respectively, showed amino acid substitutions in their PBP2 penicillin-binding domain. Substitution Ala388Ser located in motif 2 (SXD) was common to the two strains. Two additional substitutions (Ala488Thr and Leu573Val) located outside the two other motifs were identified in strain LSNy, whereas another one (Thr331Pro) located in motif 1 was identified in strain VSBj. Recombination experiments to reproduce non-susceptibility to imipenem in E. coli K12 C600 were not successful when only the common substitution was transferred, whereas recombination with DNA fragments including either the three substitutions (strain LSNy) or the two substitutions (strain VSBj) were successful. Substitution of amino acids in the penicillin-binding domain of PBP2 is a new mechanism by which E. coli clinical isolates specifically resist imipenem. © The Author 2015. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  19. Process for improving the separation efficiency in the isolation of radioactive isotopes in elementary or chemically bonded form from liquids and gases

    International Nuclear Information System (INIS)

    Schmidberger, R.; Kirch, R.; Kock, W.

    1986-01-01

    In the process for the improvement of the separation efficiency in the isolation of radioactive isotopes in elementary or chemically bonded form from liquids or gases by ion exchange and adsorption, non-radioactive isotopes of the element to be isolated are added to the fluid before the isolation, whereas at the same time a large surplus of the non-radioactive isotopes to the radioactive isotopes is achieved by addition of only small quantities of compounds of the non-radioactive isotopes. (orig./RB) [de

  20. Conformational analysis of isolated domains of Helicobacter pylori CagA.

    Directory of Open Access Journals (Sweden)

    Amanda P Woon

    Full Text Available The CagA protein of Helicobacter pylori is associated with increased virulence and gastric cancer risk. CagA is translocated into the host cell by a H. pylori type IV secretion system via mechanisms that are poorly understood. Translocated CagA interacts with numerous host factors, altering a variety of host signalling pathways. The recently determined crystal structure of C-terminally-truncated CagA indicated the presence of two domains: the smaller, flexible N-terminal domain and the larger, middle domain. In this study, we have investigated the conformation, oligomeric state and stability of the N-terminal, middle and glutamate-proline-isoleucine-tyrosine-alanine (EPIYA-repeats domains. All three domains are monomeric, suggesting that the multimerisation of CagA observed in infected cells is likely to be mediated not by CagA itself but by its interacting partners. The middle and the C-terminal domains, but not the N-terminal domain, are capable of refolding spontaneously upon heat denaturation, lending support to the hypothesis that unfolded CagA is threaded C-terminus first through the type IV secretion channel with its N-terminal domain, which likely requires interactions with other domains to refold, being threaded last. Our findings also revealed that the C-terminal EPIYA-repeats domain of CagA exists in an intrinsically disordered premolten globule state with regions in PPII conformation--a feature that is shared by many scaffold proteins that bind multiple protein components of signalling pathways. Taken together, these results provide a deeper understanding of the physicochemical properties of CagA that underpin its complex cellular and oncogenic functions.

  1. Analysis of spatial and temporal spectra of liquid film surface in annular gas-liquid flow

    Science.gov (United States)

    Alekseenko, Sergey; Cherdantsev, Andrey; Heinz, Oksana; Kharlamov, Sergey; Markovich, Dmitriy

    2013-09-01

    Wavy structure of liquid film in annular gas-liquid flow without liquid entrainment consists of fast long-living primary waves and slow short-living secondary waves. In present paper, results of spectral analysis of this wavy structure are presented. Application of high-speed LIF technique allowed us to perform such analysis in both spatial and temporal domains. Power spectra in both domains are characterized by one-humped shape with long exponential tail. Influence of gas velocity, liquid Reynolds number, liquid viscosity and pipe diameter on frequency of the waves is investigated. When gravity effect is much lesser than the shear stress, similarity of power spectra at different gas velocities is observed. Using combination of spectral analysis and identification of characteristic lines of primary waves, frequency of generation of secondary waves by primary waves is measured.

  2. High-throughput isolation of giant viruses in liquid medium using automated flow cytometry and fluorescence staining.

    Directory of Open Access Journals (Sweden)

    Jacques Yaacoub Bou Khalil

    2016-01-01

    Full Text Available The isolation of giant viruses using amoeba co-culture is tedious and fastidious. Recently, the procedure was successfully associated with a method that detects amoebal lysis on agar plates. However, the procedure remains time-consuming and is limited to protozoa growing on agar. We present here advances for the isolation of giant viruses. A high-throughput automated method based on flow cytometry and fluorescent staining was used to detect the presence of giant viruses in liquid medium. Development was carried out with the Acanthamoeba polyphaga strain widely used in past and current co-culture experiments. The proof of concept was validated with virus suspensions: artificially contaminated samples but also environmental samples from which viruses were previously isolated. After validating the technique, and fortuitously isolating a new Mimivirus, we automated the technique on 96-well plates and tested it on clinical and environmental samples using other protozoa. This allowed us to detect more than ten strains of previously known species of giant viruses and 7 new strains of a new virus lineage. This automated high-throughput method demonstrated significant time saving, and higher sensitivity than older techniques. It thus creates the means to isolate giant viruses at high speed.

  3. Measuring order in disordered systems and disorder in ordered systems: Random matrix theory for isotropic and nematic liquid crystals and its perspective on pseudo-nematic domains

    Science.gov (United States)

    Zhao, Yan; Stratt, Richard M.

    2018-05-01

    Surprisingly long-ranged intermolecular correlations begin to appear in isotropic (orientationally disordered) phases of liquid crystal forming molecules when the temperature or density starts to close in on the boundary with the nematic (ordered) phase. Indeed, the presence of slowly relaxing, strongly orientationally correlated, sets of molecules under putatively disordered conditions ("pseudo-nematic domains") has been apparent for some time from light-scattering and optical-Kerr experiments. Still, a fully microscopic characterization of these domains has been lacking. We illustrate in this paper how pseudo-nematic domains can be studied in even relatively small computer simulations by looking for order-parameter tensor fluctuations much larger than one would expect from random matrix theory. To develop this idea, we show that random matrix theory offers an exact description of how the probability distribution for liquid-crystal order parameter tensors converges to its macroscopic-system limit. We then illustrate how domain properties can be inferred from finite-size-induced deviations from these random matrix predictions. A straightforward generalization of time-independent random matrix theory also allows us to prove that the analogous random matrix predictions for the time dependence of the order-parameter tensor are similarly exact in the macroscopic limit, and that relaxation behavior of the domains can be seen in the breakdown of the finite-size scaling required by that random-matrix theory.

  4. Isolation and characterization of a J domain protein that interacts with ARC1 from ornamental kale (Brassica oleracea var. acephala).

    Science.gov (United States)

    Lan, Xingguo; Yang, Jia; Cao, Mingming; Wang, Yanhong; Kawabata, Saneyuki; Li, Yuhua

    2015-05-01

    A novel J domain protein, JDP1, was isolated from ornamental kale. The C-terminus of JDP1 specifically interacted with ARC1, which has a conserved role in self-incompatibility signaling. Armadillo (ARM)-repeat containing 1 (ARC1) plays a conserved role in self-incompatibility signaling across the Brassicaceae and functions downstream of the S-locus receptor kinase. Here, we identified a J domain protein 1 (JDP1) that interacts with ARC1 using a yeast two-hybrid screen against a stigma cDNA library from ornamental kale (Brassica oleracea var. acephala). JDP1, a 38.4-kDa protein with 344 amino acids, is a member of the Hsp40 family. Fragment JDP1(57-344), originally isolated from a yeast two-hybrid cDNA library, interacted specifically with ARC1 in yeast two-hybrid assays. The N-terminus of JDP1 (JDP1(1-68)) contains a J domain, and the C-terminus of JDP1 (JDP1(69-344)) contains an X domain of unknown function. However, JDP1(69-344) was required and sufficient for interaction with ARC1 in yeast two-hybrid assays and in vitro binding assays. Moreover, JDP1(69-344) regulated the trafficking of ARC1 from the cytoplasm to the plasma membrane by interacting with ARC1 in Arabidopsis mesophyll protoplasts. Finally, Tyr(8) in the JDP1 N-terminal region was identified to be the specific site for regulating the interaction between JDP1 and BoARC1 in yeast two-hybrid assays. Possible roles of JDP1 as an interactor with ARC1 in Brassica are discussed.

  5. Irradiation of Liquid Fungi Isolated Media from Contaminated Sources with Heavy Metals Additive

    International Nuclear Information System (INIS)

    Tawfiq, E.; Mohamed, A.A.; El-Kabbany, H.M.

    2012-01-01

    Occupational lead exposure is an important health issue in Egyptian workers, employees of paint factories, workers of copying centres, drivers, and tile making factories are in higher risk of lead toxicity. Wastewater, particularly from electroplating, paint, leather, metal and tanning industries, contain enormous amount of heavy metals. Microorganisms including fungi have been reported to exclude heavy metals from wastewater through bioaccumulation and bio sorption at low cost and in eco-friendly way. Low level lead exposure can significantly induce motor dis functions and cognitive impairment in children. Seventy six fungal isolates tolerant to heavy metals like Pb, Cd, Cr and Ni were isolated from sewage, sludge and industrial effluents containing heavy metals. Four fungi (Phanerochaete chrysosporium, Aspergillus awamori, Aspergillus flavus, Trichoderma viride) were included in this study. The majority of the fungal isolates were able to tolerate up to 400 ppm concentration of Pb, Cd, Cr and Ni. The most heavy metal tolerant fungi were studied for removal of heavy metals from liquid media at 50 ppm concentration. Results indicated removal of substantial amount of heavy metals by some of the fungi with respect to Pb, Cd, Cr and Ni with maximum uptake of 59.67, 16.25, 0.55 and 0.55 mg/g by fungi Pb 3 (Aspergillus terreus), Trichoderma viride, C r 8 (Trichoderma longibrachiatum), and isolate Ni 27 (A. niger), respectively. This indicated the potential of these fungi as bio sorbent for removal of heavy metals from wastewater and industrial effluents containing higher concentration of heavy metals. The F-ratio was 0.55 and gives non-significant as irradiated

  6. Liquid hydrogen and deuterium targets; Cibles a hydrogene et deuterium liquides

    Energy Technology Data Exchange (ETDEWEB)

    Bougon, M; Marquet, M; Prugne, P [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1961-07-01

    A description is given of 1) Atmospheric pressure target: liquid hydrogen, 400 mm thickness; thermal insulation: styrofoam; the hydrogen vapors are used to improve the target cooling; Mylar windows. 2) Vacuum target: 12 liter content: hydrogen or deuterium; liquid thickness 400 mm; thermal insulation is afforded by a vacuum vessel and a liquid nitrogen shield. Recovery and liquefaction of deuterium vapors are managed in the vacuum vessel which holds the target. The target emptying system is designed for operating in a few minutes. (author) [French] Description de: 1) Cible a pression atmospherique; hydrogene liquide, 400 mm d'epaisseur; l'isolement thermique: styrofoam; on utilise les vapeurs d'hydrogene pour ameliorer le refroidissement de la cible; hublots en Mylar. 2) Cible sous vide; contenance 12 litres; hydrogene ou deuterium; epaisseur du liquide 400 mm; l'isolement thermique est assure par une cuve a vide et un ecran d'azote liquide. Recuperation et liquefaction des vapeurs de deuterium sont effectuees dans la cuve a vide contenant la cible. Le systeme de vidange pour la cible est concu pour fonctionner en quelques minutes. (auteur)

  7. Tri-domain Bifunctional Inhibitor of Metallocarboxypeptidases A and Serine Proteases Isolated from Marine Annelid Sabellastarte magnifica*

    Science.gov (United States)

    Alonso-del-Rivero, Maday; Trejo, Sebastian A.; Reytor, Mey L.; Rodriguez-de-la-Vega, Monica; Delfin, Julieta; Diaz, Joaquin; González-González, Yamile; Canals, Francesc; Chavez, Maria Angeles; Aviles, Francesc X.

    2012-01-01

    This study describes a novel bifunctional metallocarboxypeptidase and serine protease inhibitor (SmCI) isolated from the tentacle crown of the annelid Sabellastarte magnifica. SmCI is a 165-residue glycoprotein with a molecular mass of 19.69 kDa (mass spectrometry) and 18 cysteine residues forming nine disulfide bonds. Its cDNA was cloned and sequenced by RT-PCR and nested PCR using degenerated oligonucleotides. Employing this information along with data derived from automatic Edman degradation of peptide fragments, the SmCI sequence was fully characterized, indicating the presence of three bovine pancreatic trypsin inhibitor/Kunitz domains and its high homology with other Kunitz serine protease inhibitors. Enzyme kinetics and structural analyses revealed SmCI to be an inhibitor of human and bovine pancreatic metallocarboxypeptidases of the A-type (but not B-type), with nanomolar Ki values. SmCI is also capable of inhibiting bovine pancreatic trypsin, chymotrypsin, and porcine pancreatic elastase in varying measures. When the inhibitor and its nonglycosylated form (SmCI N23A mutant) were overproduced recombinantly in a Pichia pastoris system, they displayed the dual inhibitory properties of the natural form. Similarly, two bi-domain forms of the inhibitor (recombinant rSmCI D1-D2 and rSmCI D2-D3) as well as its C-terminal domain (rSmCI-D3) were also overproduced. Of these fragments, only the rSmCI D1-D2 bi-domain retained inhibition of metallocarboxypeptidase A but only partially, indicating that the whole tri-domain structure is required for such capability in full. SmCI is the first proteinaceous inhibitor of metallocarboxypeptidases able to act as well on another mechanistic class of proteases (serine-type) and is the first of this kind identified in nature. PMID:22411994

  8. Isolation and selection of new biosurfactant producing bacteria from degraded palm kernel cake under liquid state fermentation.

    Science.gov (United States)

    Jamal, Parveen; Mir, Shajrat; Alam, Md Zahangir; Wan Nawawi, Wan M Fazli

    2014-01-01

    Biosurfactants are surface-active compounds produced by different microorganisms. The aim of this study was to introduce palm kernel cake (PKC) as a novel substrate for biosurfactant production using a potent bacterial strain under liquid state fermentation. This study was primarily based on the isolation and identification of biosurfactant-producing bacteria that could utilize palm kernel cake as a new major substrate. Potential bacterial strains were isolated from degraded PKC and screened for biosurfactant production with the help of the drop collapse assay and by analyzing the surface tension activity. From the screened isolates, a new strain, SM03, showed the best and most consistent results, and was therefore selected as the most potent biosurfactant-producing bacterial strain. The new strain was identified as Providencia alcalifaciens SM03 using the Gen III MicroPlate Biolog Microbial Identification System. The yield of the produced biosurfactant was 8.3 g/L.

  9. Isolation of Panels of Llama Single-Domain Antibody Fragments Binding All Nine Neuraminidase Subtypes of Influenza A Virus

    Directory of Open Access Journals (Sweden)

    Guus Koch

    2013-04-01

    Full Text Available Avian influenza A virus comprises sixteen hemagglutinin (HA and nine neuraminidase (NA subtypes (N1–N9. To isolate llama single-domain antibody fragments (VHHs against all N subtypes, four llamas were immunized with mixtures of influenza viruses. Selections using influenza virus yielded predominantly VHHs binding to the highly immunogenic HA and nucleoprotein. However, selection using enzymatically active recombinant NA (rNA protein enabled us to isolate NA binding VHHs. Some isolated VHHs cross-reacted to other N subtypes. These were subsequently used for the capture of N subtypes that could not be produced as recombinant protein (rN6 or were enzymatically inactive (rN1, rN5 in phage display selection, yielding novel VHHs. In total we isolated 188 NA binding VHHs, 64 of which were expressed in yeast. Most VHHs specifically recognize a single N subtype, but some VHHs cross-react with other N-subtypes. At least one VHH bound to all N subtypes, except N4, identifying a conserved antigenic site. Thus, this work (1 describes methods for isolating NA binding VHHs, (2 illustrates the suitability of llama immunization with multiple antigens for retrieving many binders against different antigens and (3 describes 64 novel NA binding VHHs, including a broadly reactive VHH, which can be used in various assays for influenza virus subtyping, detection or serology.

  10. Isolation of Metals from Liquid Wastes: Reactive in Turbulent Thermal Reactors

    International Nuclear Information System (INIS)

    Wendt, Jost O.L.

    2001-01-01

    A Generic Technology for treatment of DOE Metal-Bearing Liquid Waste The DOE metal-bearing liquid waste inventory is large and diverse, both with respect to the metals (heavy metals, transuranics, radionuclides) themselves, and the nature of the other species (annions, organics, etc.) present. Separation and concentration of metals is of interest from the standpoint of reducing the volume of waste that will require special treatment or isolation, as well as, potentially, from the standpoint of returning some materials to commerce by recycling. The variety of metal-bearing liquid waste in the DOE complex is so great that it is unlikely that any one process (or class of processes) will be suitable for all material. However, processes capable of dealing with a wide variety of wastes will have major advantages in terms of process development, capital, and operating costs, as well as in environmental and safety permitting. Moreover, to the extent that a process operates well with a variety of metal-bearing liquid feedwastes, its performance is likely to be relatively robust with respect to the inevitable composition variations in each waste feed. One such class of processes involves high-temperature treatment of atomized liquid waste to promote reactive capture of volatile metallic species on collectible particulate substrates injected downstream of a flame zone. Compared to low-temperature processes that remove metals from the original liquid phase by extraction, precipitation, ion exchange, etc., some of the attractive features of high-temperature reactive scavenging are: The organic constituents of some metal-bearing liquid wastes (in particular, some low-level mixed wastes) must be treated thermally in order to meet the requirements of the Resource Conservation and Recovery Act (RCRA) and Toxic Substances Control Act (TSCA), and the laws of various states. No species need be added to an already complex liquid system. This is especially important in light of the fact

  11. Fault Isolation for Shipboard Decision Support

    DEFF Research Database (Denmark)

    Lajic, Zoran; Blanke, Mogens; Nielsen, Ulrik Dam

    2010-01-01

    Fault detection and fault isolation for in-service decision support systems for marine surface vehicles will be presented in this paper. The stochastic wave elevation and the associated ship responses are modeled in the frequency domain. The paper takes as an example fault isolation of a containe......Fault detection and fault isolation for in-service decision support systems for marine surface vehicles will be presented in this paper. The stochastic wave elevation and the associated ship responses are modeled in the frequency domain. The paper takes as an example fault isolation...... to the quality of decisions given to navigators....

  12. Fluctuating hydrodynamics for ionic liquids

    Energy Technology Data Exchange (ETDEWEB)

    Lazaridis, Konstantinos [Department of Mathematics and Statistics, Washington State University, Pullman, 99163 (United States); Wickham, Logan [Department of Computer Science, Washington State University, Richland, 99354 (United States); Voulgarakis, Nikolaos, E-mail: n.voulgarakis@wsu.edu [Department of Mathematics and Statistics, Washington State University, Pullman, 99163 (United States)

    2017-04-25

    We present a mean-field fluctuating hydrodynamics (FHD) method for studying the structural and transport properties of ionic liquids in bulk and near electrified surfaces. The free energy of the system consists of two competing terms: (1) a Landau–Lifshitz functional that models the spontaneous separation of the ionic groups, and (2) the standard mean-field electrostatic interaction between the ions in the liquid. The numerical approach used to solve the resulting FHD-Poisson equations is very efficient and models thermal fluctuations with remarkable accuracy. Such density fluctuations are sufficiently strong to excite the experimentally observed spontaneous formation of liquid nano-domains. Statistical analysis of our simulations provides quantitative information about the properties of ionic liquids, such as the mixing quality, stability, and the size of the nano-domains. Our model, thus, can be adequately parameterized by directly comparing our prediction with experimental measurements and all-atom simulations. Conclusively, this work can serve as a practical mathematical tool for testing various theories and designing more efficient mixtures of ionic liquids. - Highlights: • A new fluctuating hydrodynamics method for ionic liquids. • Description of ionic liquid morphology in bulk and near electrified surfaces. • Direct comparison with experimental measurements.

  13. Liquid metal pump

    Science.gov (United States)

    Pennell, William E.

    1982-01-01

    The liquid metal pump comprises floating seal rings and attachment of the pump diffuser to the pump bowl for isolating structural deflections from the pump shaft bearings. The seal rings also eliminate precision machining on large assemblies by eliminating the need for a close tolerance fit between the mounting surfaces of the pump and the seals. The liquid metal pump also comprises a shaft support structure that is isolated from the pump housing for better preservation of alignment of shaft bearings. The shaft support structure also allows for complete removal of pump internals for inspection and repair.

  14. Liquid metal pump

    International Nuclear Information System (INIS)

    Pennell, W.E.

    1982-01-01

    The liquid metal pump comprises floating seal rings and attachment of the pump diffuser to the pump bowl for isolating structural deflections from the pump shaft bearings. The seal rings also eliminate precision machining on large assemblies by eliminating the need for a close tolerance fit between the mounting surfaces of the pump and the seals. The liquid metal pump also comprises a shaft support structure that is isolated from the pump housing for better preservation of alignment of shaft bearings. The shaft support structure also allows for complete removal of pump internals for inspection and repair

  15. Imaging lipid domains in cell membranes: the advent of super-resolution fluorescence microscopy

    Directory of Open Access Journals (Sweden)

    Dylan Myers Owen

    2013-12-01

    Full Text Available The lipid bilayer of model membranes, liposomes reconstituted from cell lipids, and plasma membrane vesicles and spheres can separate into two distinct liquid phases to yield lipid domains with liquid-ordered and liquid-disordered properties. These observations are the basis of the lipid raft hypothesis that postulates the existence of cholesterol-enriched ordered-phase lipid domains in cell membranes that could regulate protein mobility, localization and interaction. Here we review the evidence that nano-scaled lipid complexes and meso-scaled lipid domains exist in cell membranes and how new fluorescence microscopy techniques that overcome the diffraction limit provide new insights into lipid organization in cell membranes.

  16. Sloshing of coolant in a seismically isolated reactor

    International Nuclear Information System (INIS)

    Wu, T.S.; Guildys, J.; Seidensticker, R.W.

    1988-01-01

    During a seismic event, the liquid coolant inside the reactor vessel has sloshing motion which is a low-frequency phenomenon. In a reactor system incorporated with seismic isolation, the isolation frequency usually is also very low. There is concern on the potential amplification of sloshing motion of the liquid coolant. This study investigates the effects of seismic isolation on the sloshing of liquid coolant inside the reactor vessel of a liquid metal cooled reactor. Based on a synthetic ground motion whose response spectra envelop those specified by the NRC Regulator Guide 1.60, it is found that the maximum sloshing wave height increases from 18 in. to almost 30 in. when the system is seismically isolated. Since higher sloshing wave may introduce severe impact forces and thermal shocks to the reactor closure and other components within the reactor vessel, adequate design considerations should be made either to suppress the wave height or to reduce the effects caused by high waves

  17. Lipid composition of membrane rafts, isolated with and without detergent, from the spleen of a mouse model of Gaucher disease.

    Science.gov (United States)

    Hattersley, Kathryn J; Hein, Leanne K; Fuller, Maria

    2013-12-06

    Biological membranes are composed of functionally relevant liquid-ordered and liquid-disordered domains that coexist. Within the liquid-ordered domains are low-density microdomains known as rafts with a unique lipid composition that is crucial for their structure and function. Lipid raft composition is altered in sphingolipid storage disorders, and here we determined the lipid composition using a detergent and detergent-free method in spleen tissue, the primary site of pathology, in a mouse model of the sphingolipid storage disorder, Gaucher disease. The accumulating lipid, glucosylceramide, was 30- and 50-fold elevated in the rafts with the detergent and detergent-free method, respectively. Secondary accumulation of di- and trihexosylceramide resided primarily in the rafts with both methods. The phospholipids distributed differently with more than half residing in the rafts with the detergent-free method and less than 10% with the detergent method, with the exception of the fully saturated species that were primarily in the rafts. Individual isoforms of sphingomyelin correlated with detergent-free extraction and more than half resided in the raft fractions. However, this correlation was not seen with the detergent extraction method as sphingomyelin species were spread across both the raft and non-raft domains. Therefore caution must be exercised when interpreting phospholipid distribution in raft domains as it differs considerably depending on the method of isolation. Importantly, both methods revealed the same lipid alterations in the raft domains in the spleen of the Gaucher disease mouse model highlighting that either method is appropriate to determine membrane lipid changes in the diseased state. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Giant Plasma Membrane Vesicles: An Experimental Tool for Probing the Effects of Drugs and Other Conditions on Membrane Domain Stability.

    Science.gov (United States)

    Gerstle, Zoe; Desai, Rohan; Veatch, Sarah L

    2018-01-01

    Giant plasma membrane vesicles (GPMVs) are isolated directly from living cells and provide an alternative to vesicles constructed of synthetic or purified lipids as an experimental model system for use in a wide range of assays. GPMVs capture much of the compositional protein and lipid complexity of intact cell plasma membranes, are filled with cytoplasm, and are free from contamination with membranes from internal organelles. GPMVs often exhibit a miscibility transition below the growth temperature of their parent cells. GPMVs labeled with a fluorescent protein or lipid analog appear uniform on the micron-scale when imaged above the miscibility transition temperature, and separate into coexisting liquid domains with differing membrane compositions and physical properties below this temperature. The presence of this miscibility transition in isolated GPMVs suggests that a similar phase-like heterogeneity occurs in intact plasma membranes under growth conditions, albeit on smaller length scales. In this context, GPMVs provide a simple and controlled experimental system to explore how drugs and other environmental conditions alter the composition and stability of phase-like domains in intact cell membranes. This chapter describes methods to generate and isolate GPMVs from adherent mammalian cells and to interrogate their miscibility transition temperatures using fluorescence microscopy. © 2018 Elsevier Inc. All rights reserved.

  19. Isolation and screening of azo dye decolorizing bacterial isolates from dye-contaminated textile wastewater

    Directory of Open Access Journals (Sweden)

    Shahid Mahmood

    2011-04-01

    Full Text Available Azo dyes are released into wastewater streams without any pretreatment and pollute water and soilenvironments. To prevent contamination of our vulnerable resources, removal of these dye pollutants is of greatimportance. For this purpose, wastewater samples were collected from dye-contaminated sites of Faisalabad. About200 bacterial isolates were isolated through enrichment and then tested for their potential to remove RemazolBlack-B azo dye in liquid medium. Five bacterial isolates capable of degrading Remazol Black-B azo dye efficientlywere screened through experimentation on modified mineral salt medium. Isolate SS1 (collected from wastewater ofSupreme Textile Industry was able to completely remove the Remazol Black-B dye from the liquid medium in 18 h.Further, the isolate showed the best performance at the dye concentration of 100 mg L-1 medium (pH 7 and attemperature 35oC. Similarly, yeast extract proved to be the best carbon source for decolorization purpose. Theresults imply that the isolate SS1 could be used for the removal of the reactive dyes from textile effluents.

  20. The HIV-1 V3 domain on field isolates: participation in generation of escape virus in vivo and accessibility to neutralizing antibodies

    DEFF Research Database (Denmark)

    Arendrup, M; Akerblom, L; Heegaard, P M

    1995-01-01

    The V3 domain is highly variable and induces HIV neutralizing antibodies (NA). Here we addressed the issues of 1) the participation of mutations in V3 in generation of neutralization resistant escape virus in vivo and 2) the applicability of synthetic V3 peptides corresponding to field isolates...... patterns against V3 peptides corresponding to sequential primary and escape field isolates, with the strongest reactivity against late isolated escape virus. These observations suggest that the neutralization epitope was influenced by the appearance of mutations. When used as immunogen in rabbits, V3...... to induce neutralizing immune sera. Seven peptides corresponding to the V3 region of primary and escape virus from 3 HIV-1 infected patients were synthesized and used for antibody (Abs) studies and immunizations. The anti-V3 Abs titre in patient serum was generally low against peptides corresponding...

  1. Spirostaphylotrichin W, a spirocyclic γ-lactam isolated from liquid culture of Pyrenophora semeniperda, a potential mycoherbicide for cheatgrass (Bromus tectorum) biocontrol

    Science.gov (United States)

    Marco Masia; Susan Meyer; Suzette Clement; Anna Andolfi; Alessio Cimmino; Antonio. Evidente

    2014-01-01

    A novel spirocyclic γ-lactam, named spirostaphylotrichin W (1), was isolated together with the well known and closely related spirostaphylotrichins A, C, D, R and V, as well as triticone E, from the liquid cultures of Pyrenophora semeniperda (anamorph: Drechslera), a seed pathogen proposed for cheatgrass (Bromus tectorum) biocontrol. Spirostaphylotrichin W was...

  2. Soft ionization of thermally evaporated hypergolic ionic liquid aerosols

    Energy Technology Data Exchange (ETDEWEB)

    University of California; ERC, Incorporated, Edwards Air Force Base; Air Force Research Laboratory, Edwards Air Force Base; National Synchrotron Radiation Research Center (NSRRC); Institute of Chemistry, Hebrew University; Koh, Christine J.; Liu, Chen-Lin; Harmon, Christopher W.; Strasser, Daniel; Golan, Amir; Kostko, Oleg; Chambreau, Steven D.; Vaghjiani, Ghanshyam L.; Leone, Stephen R.

    2011-07-19

    Isolated ion pairs of a conventional ionic liquid, 1-Ethyl-3-Methyl-Imidazolium Bis(trifluoromethylsulfonyl)imide ([Emim+][Tf2N?]), and a reactive hypergolic ionic liquid, 1-Butyl-3-Methyl-Imidazolium Dicyanamide ([Bmim+][Dca?]), are generated by vaporizing ionic liquid submicron aerosol particles for the first time; the vaporized species are investigated by dissociative ionization with tunable vacuum ultraviolet (VUV) light, exhibiting clear intact cations, Emim+ and Bmim+, presumably originating from intact ion pairs. Mass spectra of ion pair vapor from an effusive source of the hypergolic ionic liquid show substantial reactive decomposition due to the internal energy of the molecules emanating from the source. Photoionization efficiency curves in the near threshold ionization region of isolated ion pairs of [Emim+][Tf2N?]ionic liquid vapor are compared for an aerosol source and an effusive source, revealing changes in the appearance energy due to the amount of internal energy in the ion pairs. The aerosol source has a shift to higher threshold energy (~;;0.3 eV), attributed to reduced internal energy of the isolated ion pairs. The method of ionic liquid submicron aerosol particle vaporization, for reactive ionic liquids such as hypergolic species, is a convenient, thermally ?cooler? source of isolated intact ion pairs in the gas phase compared to effusive sources.

  3. Structural analysis of zwitterionic liquids vs. homologous ionic liquids

    Science.gov (United States)

    Wu, Boning; Kuroda, Kosuke; Takahashi, Kenji; Castner, Edward W.

    2018-05-01

    Zwitterionic liquids (Zw-ILs) have been developed that are homologous to monovalent ionic liquids (ILs) and show great promise for controlled dissolution of cellulosic biomass. Using both high energy X-ray scattering and atomistic molecular simulations, this article compares the bulk liquid structural properties for novel Zw-ILs with their homologous ILs. It is shown that the significant localization of the charges on Zw-ILs leads to charge ordering similar to that observed for conventional ionic liquids with monovalent anions and cations. A low-intensity first sharp diffraction peak in the liquid structure factor S(q) is observed for both the Zw-IL and the IL. This is unexpected since both the Zw-IL and IL have a 2-(2-methoxyethoxy)ethyl (diether) functional group on the cationic imidazolium ring and ether functional groups are known to suppress this peak. Detailed analyses show that this intermediate range order in the liquid structure arises for slightly different reasons in the Zw-IL vs. the IL. For the Zw-IL, the ether tails in the liquid are shown to aggregate into nanoscale domains.

  4. Analysis of von Willebrand factor A domain-related protein (WARP polymorphism in temperate and tropical Plasmodium vivax field isolates

    Directory of Open Access Journals (Sweden)

    Zakeri Sedigheh

    2009-06-01

    Full Text Available Abstract Background The identification of key molecules is crucial for designing transmission-blocking vaccines (TBVs, among those ookinete micronemal proteins are candidate as a general class of malaria transmission-blocking targets. Here, the sequence analysis of an extra-cellular malaria protein expressed in ookinetes, named von Willebrand factor A domain-related protein (WARP, is reported in 91 Plasmodium vivax isolates circulating in different regions of Iran. Methods Clinical isolates were collected from north temperate and southern tropical regions in Iran. Primers have been designed based on P. vivax sequence (ctg_6991 which amplified a fragment of about 1044 bp with no size variation. Direct sequencing of PCR products was used to determine polymorphism and further bioinformatics analysis in P. vivax sexual stage antigen, pvwarp. Results Amplified pvwarp gene showed 886 bp in size, with no intron. BLAST analysis showed a similarity of 98–100% to P. vivax Sal-I strain; however, Iranian isolates had 2 bp mismatches in 247 and 531 positions that were non-synonymous substitution [T (ACT to A (GCT and R (AGA to S (AGT] in comparison with the Sal-I sequence. Conclusion This study presents the first large-scale survey on pvwarp polymorphism in the world, which provides baseline data for developing WARP-based TBV against both temperate and tropical P. vivax isolates.

  5. The HIV-1 V3 domain on field isolates: participation in generation of escape virus in vivo and accessibility to neutralizing antibodies

    DEFF Research Database (Denmark)

    Arendrup, M; Akerblom, L; Heegaard, P M

    1995-01-01

    The V3 domain is highly variable and induces HIV neutralizing antibodies (NA). Here we addressed the issues of 1) the participation of mutations in V3 in generation of neutralization resistant escape virus in vivo and 2) the applicability of synthetic V3 peptides corresponding to field isolates...... to induce neutralizing immune sera. Seven peptides corresponding to the V3 region of primary and escape virus from 3 HIV-1 infected patients were synthesized and used for antibody (Abs) studies and immunizations. The anti-V3 Abs titre in patient serum was generally low against peptides corresponding...... to autologous virus isolated later than the serum sample in contrast to the titre against peptides corresponding to virus isolated earlier than the serum sample. Furthermore, neutralizing anti-V3 monoclonal antibodies (MAbs) raised against V3 peptides from laboratory strains of HIV-1 showed distinct binding...

  6. Soft Ionization of Thermally Evaporated Hypergolic Ionic Liquid Aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Koh, Christine J. [Univ. of California, Berkeley, CA (United States); Liu, Chen-Lin [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Harmon, Christopher W. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Strasser, Daniel [Univ. of California, Berkeley, CA (United States); Golan, Amir [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Kostko, Oleg [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chambreau, Steven D. [Edwards Air Force Base, ERC Inc., CA (United States); Vaghjiani, Ghanshyam L. [Air Force Research Laboratory, Edwards Air Force Base, CA (United States); Leone, Stephen R. [Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2011-04-20

    Isolated ion pairs of a conventional ionic liquid, 1-Ethyl-3-Methyl-Imidazolium Bis(trifluoromethylsulfonyl)imide ([Emim+][Tf2N–]), and a reactive hypergolic ionic liquid, 1-Butyl-3-Methyl-Imidazolium Dicyanamide ([Bmim+][Dca–]), are generated by vaporizing ionic liquid submicrometer aerosol particles for the first time; the vaporized species are investigated by dissociative ionization with tunable vacuum ultraviolet (VUV) light, exhibiting clear intact cations, Emim+ and Bmim+, presumably originating from intact ion pairs. Mass spectra of ion pair vapor from an effusive source of the hypergolic ionic liquid show substantial reactive decomposition due to the internal energy of the molecules emanating from the source. Also, hotoionization efficiency curves in the near threshold ionization region of isolated ion pairs of [Emim+][Tf2N] ionic liquid vapor are compared for an aerosol source and an effusive source, revealing changes in the appearance energy due to the amount of internal energy in the ion pairs. The aerosol source has a shift to higher threshold energy (~0.3 eV), attributed to reduced internal energy of the isolated ion pairs. Lastly, the method of ionic liquid submicrometer aerosol particle vaporization, for reactive ionic liquids such as hypergolic species, is a convenient, thermally “cooler” source of isolated intact ion pairs in the gas phase compared to effusive sources.

  7. Solid and Liquid Waste Drying Bag

    Science.gov (United States)

    Litwiller, Eric (Inventor); Hogan, John A. (Inventor); Fisher, John W. (Inventor)

    2009-01-01

    Method and system for processing waste from human activities, including solids, liquids and vapors. A fluid-impermeable bag, lined with a liquid-impermeable but vapor-permeable membrane, defining an inner bag, is provided. A vacuum force is provided to extract vapors so that the waste is moved toward a selected region in the inner bag, extracted vapors, including the waste vapors and vaporized portions of the waste liquids are transported across the membrane, and most or all of the solids remain within the liner. Extracted vapors are filtered, and sanitized components thereof are isolated and optionally stored. The solids remaining within the liner are optionally dried and isolated for ultimate disposal.

  8. Dynamics of solid nanoparticles near a liquid-liquid interface

    Science.gov (United States)

    Daher, Ali; Ammar, Amine; Hijazi, Abbas

    2018-05-01

    The liquid - liquid interface can be used as a suitable medium for generating some nanostructured films of metals, or inorganic materials such as semi conducting metals. This process can be controlled well if we study the dynamics of nanoparticles (NPs) at the liquid-liquid interface which is a new field of study, and is not understood well yet. The dynamics of NPs at liquid-liquid interfaces is investigated by solving the fluid-particle and particle-particle interactions. Our work is based on the Molecular Dynamics (MD) simulation in addition to Phase Field (PF) method. We modeled the liquid-liquid interface using the diffuse interface model, where the interface is considered to have a characteristic thickness. We have shown that the concentration gradient of one fluid in the other gives rise to a hydrodynamic force that drives the NPs to agglomerate at the interface. These obtained results may introduce new applications where certain interfaces can be considered to be suitable mediums for the synthesis of nanostructured materials. In addition, some liquid interfaces can play the role of effective filters for different species of biological NPs and solid state waste NPs, which will be very important in many industrial and biomedical domains.

  9. Isolation of Raoultella planticola from refillable antimicrobial liquid soap dispensers in a dental setting.

    Science.gov (United States)

    Momeni, Stephanie S; Tomlin, Nancy; Ruby, John D

    2015-04-01

    Liquid antimicrobial soaps are commonly used in the dental health care setting for hand washing to minimize the potential spread of infectious agents to health care workers and patients. The purpose of the current study was to evaluate possible bacterial contamination of antimicrobial liquid soap dispensers located in 2 institutional comprehensive dental care clinics. Fourteen soap dispensers and 16 original stock containers were sampled. A 1-milliliter aliquot was diluted in 10 mL of phosphate buffer (Tween-80; Acros). Serial dilutions were plated in duplicate on neutralizing agar and incubated for 7 days. Molecular identification was performed using 500 base pair comparisons of 16S ribosomal ribonucleic acid sequencing. Taq polymerase chain reaction was performed with sequence-specific primers for Raoultella species. Bacterial growth was observed at 18 hours for 57% (8 of 14) of soap dispenser samples. Bacterial densities ranged from 4 × 10(2) to 6 × 10(9) colony-forming units per milliliter. Original commercial containers exhibited no growth. Isolates were identified as Raoultella (Klebsiella) planticola. This is the first study to the authors' knowledge indicating recovery of R. planticola from antimicrobial liquid soap dispensers. R. planticola is a recognized environmental opportunistic pathogen that potentially poses a health concern. These findings indicate compliance problems with infection prevention recommendations and support the US Centers for Disease Control and Prevention's recommendation that dispensers should not be topped off. High bacterial loads of R. planticola are inconsistent with infection control practices and are a concern because transmission and possible infection to the health care worker or the patient may occur. Copyright © 2015 American Dental Association. Published by Elsevier Inc. All rights reserved.

  10. Topological domain walls in helimagnets

    Science.gov (United States)

    Schoenherr, P.; Müller, J.; Köhler, L.; Rosch, A.; Kanazawa, N.; Tokura, Y.; Garst, M.; Meier, D.

    2018-05-01

    Domain walls naturally arise whenever a symmetry is spontaneously broken. They interconnect regions with different realizations of the broken symmetry, promoting structure formation from cosmological length scales to the atomic level1,2. In ferroelectric and ferromagnetic materials, domain walls with unique functionalities emerge, holding great promise for nanoelectronics and spintronics applications3-5. These walls are usually of Ising, Bloch or Néel type and separate homogeneously ordered domains. Here we demonstrate that a wide variety of new domain walls occurs in the presence of spatially modulated domain states. Using magnetic force microscopy and micromagnetic simulations, we show three fundamental classes of domain walls to arise in the near-room-temperature helimagnet iron germanium. In contrast to conventional ferroics, the domain walls exhibit a well-defined inner structure, which—analogous to cholesteric liquid crystals—consists of topological disclination and dislocation defects. Similar to the magnetic skyrmions that form in the same material6,7, the domain walls can carry a finite topological charge, permitting an efficient coupling to spin currents and contributions to a topological Hall effect. Our study establishes a new family of magnetic nano-objects with non-trivial topology, opening the door to innovative device concepts based on helimagnetic domain walls.

  11. On-line comprehensive two-dimensional normal-phase liquid chromatography × reversed-phase liquid chromatography for preparative isolation of Peucedanum praeruptorum.

    Science.gov (United States)

    Wang, Xin-Yuan; Li, Jia-Fu; Jian, Ya-Mei; Wu, Zhen; Fang, Mei-Juan; Qiu, Ying-Kun

    2015-03-27

    A new on-line comprehensive preparative two-dimensional normal-phase liquid chromatography × reversed-phase liquid chromatography (2D NPLC × RPLC) system was developed for the separation of complicated natural products. It was based on the use of a silica gel packed medium-pressure column as the first dimension and an ODS preparative HPLC column as the second dimension. The two dimensions were connected with normal-phase (NP) and reversed-phase (RP) enrichment units, involving a newly developed airflow assisted adsorption (AAA) technique. The instrument operation and the performance of this NPLC × RPLC separation method were illustrated by gram-scale isolation of ethanol extract from the roots of Peucedanum praeruptorum. In total, 19 compounds with high purity were obtained via automated multi-step preparative separation in a short period of time using this system, and their structures were comprehensively characterized by ESI-MS, (1)H NMR, and (13)C NMR. Including two new compounds, five isomers in two groups with identical HPLC and TLC retention values were also obtained and identified by 1D NMR and 2D NMR. This is the first report of an NPLC × RPLC system successfully applied in an on-line preparative process. This system not only solved the interfacing problem of mobile-phase immiscibility caused by NP and RP separation, it also exhibited apparent advantages in separation efficiency and sample treatment capacity compared with conventional methods. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Isolation and characterization of a PUF-domain of pumilio gene from ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-03-20

    Mar 20, 2009 ... study, a partial pumilio gene with complete PUF-domain in Bombyx mori has been ... Key words: Bombyx mori, pumilio, PUF-domain, RACE, germline stem cell. .... The first-strand cDNA was synthesized from 2 ug of total. RNA.

  13. Interaction of an anticancer peptide fragment of azurin with p53 and its isolated domains studied by atomic force spectroscopy.

    Science.gov (United States)

    Bizzarri, Anna Rita; Santini, Simona; Coppari, Emilia; Bucciantini, Monica; Di Agostino, Silvia; Yamada, Tohru; Beattie, Craig W; Cannistraro, Salvatore

    2011-01-01

    p28 is a 28-amino acid peptide fragment of the cupredoxin azurin derived from Pseudomonas aeruginosa that preferentially penetrates cancerous cells and arrests their proliferation in vitro and in vivo. Its antitumor activity reportedly arises from post-translational stabilization of the tumor suppressor p53 normally downregulated by the binding of several ubiquitin ligases. This would require p28 to specifically bind to p53 to inhibit specific ligases from initiating proteosome-mediated degradation. In this study, atomic force spectroscopy, a nanotechnological approach, was used to investigate the interaction of p28 with full-length p53 and its isolated domains at the single molecule level. Analysis of the unbinding forces and the dissociation rate constant suggest that p28 forms a stable complex with the DNA-binding domain of p53, inhibiting the binding of ubiquitin ligases other than Mdm2 to reduce proteasomal degradation of p53.

  14. A modified approach for isolation of essential oil from fruit of Amorpha fruticosa Linn using microwave-assisted hydrodistillation concatenated liquid-liquid extraction.

    Science.gov (United States)

    Chen, Fengli; Jia, Jia; Zhang, Qiang; Gu, Huiyan; Yang, Lei

    2017-11-17

    In this work, a modified technique was developed to separate essential oil from the fruit of Amorpha fruticosa using microwave-assisted hydrodistillation concatenated liquid-liquid extraction (MHD-LLE). The new apparatus consists of two series-wound separation columns for separating essential oil, one is the conventional oil-water separation column, and the other is the extraction column of components from hydrosol using an organic solvent. Therefore, the apparatus can simultaneously collect the essential oil separated on the top of hydrosol and the components extracted from hydrosol using an organic solvent. Based on the yield of essential oil in the first and second separation columns, the effects of parameters were investigated by single factor experiments and Box-Behnken design. Under the optimum conditions (2mL ethyl ether as the extraction solvent in the second separation column, 12mL/g liquid-solid ratio, 4.0min homogenate time, 35min microwave irradiation time and 540W microwave irradiation power), satisfactory yields for the essential oil in the first separation column (10.31±0.33g/kg) and second separation column (0.82±0.03g/kg) were obtained. Compared with traditional methods, the developed method gave a higher yield of essential oil in a shorter time. In addition, GC-MS analysis of the essential oil indicated significant differences of the relative contents of individual volatile components in the essential oils obtained in the two separation columns. Therefore, the MHD-LLE technique developed here is a good alternative for the isolation of essential oil from A. fruticosa fruit as well as other herbs. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Effect of membrane microheterogeneity and domain size on fluorescence resonance energy transfer.

    Science.gov (United States)

    Towles, Kevin B; Brown, Angela C; Wrenn, Steven P; Dan, Nily

    2007-07-15

    Studies of multicomponent membranes suggest lateral inhomogeneity in the form of membrane domains, but the size of small (nanoscale) domains in situ cannot be determined with current techniques. In this article, we present a model that enables extraction of membrane domain size from time-resolved fluorescence resonance energy transfer (FRET) data. We expand upon a classic approach to the infinite phase separation limit and formulate a model that accounts for the presence of disklike domains of finite dimensions within a two-dimensional infinite planar bilayer. The model was tested against off-lattice Monte Carlo calculations of a model membrane in the liquid-disordered (l(d)) and liquid-ordered (l(o)) coexistence regime. Simulated domain size was varied from 5 to 50 nm, and two fluorophores, preferentially partitioning into opposite phases, were randomly mixed to obtain the simulated time-resolved FRET data. The Monte Carlo data show clear differences in the efficiency of energy transfer as a function of domain size. The model fit of the data yielded good agreement for the domain size, especially in cases where the domain diameter is membrane domains using time-resolved FRET.

  16. A polysaccharide isolated from the liquid culture of Lentinus edodes (shiitake) mushroom mycelia containing black rice bran protects mice against a Salmonella lipopolysaccharide-induced endotoxemia

    Science.gov (United States)

    Endotoxemia (sepsis, septic shock) is an inflammatory, virulent disease that results mainly from bacterial infection. The present study investigates the inhibitory effect of the bio-processed polysaccharide (BPP) isolated from the edible Lentinus edodes liquid mycelial mushroom culture supplemented...

  17. Isolation of previously uncultured rumen bacteria by dilution to extinction using a new liquid culture medium.

    Science.gov (United States)

    Kenters, Nikki; Henderson, Gemma; Jeyanathan, Jeyamalar; Kittelmann, Sandra; Janssen, Peter H

    2011-01-01

    A new anaerobic medium that mimics the salts composition of rumen fluid was used in conjunction with a dilution method of liquid culture to isolate fermentative bacteria from the rumen of a grass-fed sheep. The aim was to inoculate a large number of culture tubes each with a mean of 97% sequence identity to genes of uncultured bacteria detected in various gastrointestinal environments. This strategy has therefore allowed us to cultivate many novel rumen bacteria, opening the way to overcoming the lack of cultures of many of the groups detected using cultivation-independent methods. Copyright © 2010 Elsevier B.V. All rights reserved.

  18. Static and dynamic stability of pneumatic vibration isolators and systems of isolators

    Science.gov (United States)

    Ryaboy, Vyacheslav M.

    2014-01-01

    Pneumatic vibration isolation is the most widespread effective method for creating vibration-free environments that are vital for precise experiments and manufacturing operations in optoelectronics, life sciences, microelectronics, nanotechnology and other areas. The modeling and design principles of a dual-chamber pneumatic vibration isolator, basically established a few decades ago, continue to attract attention of researchers. On the other hand, behavior of systems of such isolators was never explained in the literature in sufficient detail. This paper covers a range of questions essential for understanding the mechanics of pneumatic isolation systems from both design and application perspectives. The theory and a model of a single standalone isolator are presented in concise form necessary for subsequent analysis. Then the dynamics of a system of isolators supporting a payload is considered with main attention directed to two aspects of their behavior: first, the static stability of payloads with high positions of the center of gravity; second, dynamic stability of the feedback system formed by mechanical leveling valves. The direct method of calculating the maximum stable position of the center of gravity is presented and illustrated by three-dimensional stability domains; analytic formulas are given that delineate these domains. A numerical method for feedback stability analysis of self-leveling valve systems is given, and the results are compared with the analytical estimates for a single isolator. The relation between the static and dynamic phenomena is discussed.

  19. Psychopathology and friendship in children and adolescents: disentangling the role of co-occurring symptom domains with serial mediation models.

    Science.gov (United States)

    Manfro, Arthur Gus; Pan, Pedro M; Gadelha, Ary; Fleck, Marcelo; do Rosário, Maria C; Cogo-Moreira, Hugo; Affonseca-Bressan, Rodrigo; Mari, Jair; Miguel, Euripedes C; Rohde, Luis A; Salum, Giovanni A

    2017-11-01

    The consolidation of social friendship groups is a vital part of human development. The objective of this study is to understand the direct and indirect influences of three major symptomatic domains-emotional, hyperkinetic, and conduct-on friendship. Specifically, we aim to study if the associations of one domain with friendship may be mediated by co-occurring symptoms from another domain. A total of 2512 subjects aged 6-14 years participated in this study. Friendship was evaluated by the Development and Well-Being Assessment's friendship section. We evaluated two main constructs as outcomes: (1) social isolation and (2) friendship latent construct. Emotional, hyperkinetic, and conduct symptomatic domains were evaluated with the Strengths and Difficulties Questionnaire (SDQ). All SDQ domains were positively associated with social isolation and negatively associated with friendship latent construct in univariate analysis. However, serial mediation models showed that the association between conduct domains with social isolation was mediated by emotion and hyperkinetic domains. Moreover, the associations between emotional and hyperkinetic domains with friendship latent construct in non-isolated children were mediated by the conduct domain. Emotion and hyperkinetic domains were directly and indirectly associated with social isolation, whereas conduct was directly and indirectly associated with overall friendship in non-isolated children. Results suggest that interventions aimed to improve social life in childhood and adolescence may have stronger effects if directed towards the treatment of emotion and hyperkinetic symptoms in socially isolated children and directed towards the treatment of conduct symptoms in children with fragile social connections.

  20. Dynamical, structural and chemical heterogeneities in a binary metallic glass-forming liquid

    Science.gov (United States)

    Puosi, F.; Jakse, N.; Pasturel, A.

    2018-04-01

    As it approaches the glass transition, particle motion in liquids becomes highly heterogeneous and regions with virtually no mobility coexist with liquid-like domains. This complex dynamic is believed to be responsible for different phenomena including non-exponential relaxation and the breakdown of the Stokes-Einstein relation. Understanding the relationships between dynamical heterogeneities and local structure in metallic liquids and glasses is a major scientific challenge. Here we use classical molecular dynamics simulations to study the atomic dynamics and microscopic structure of Cu50Zr50 alloy in the supercooling regime. Dynamical heterogeneities are identified via an isoconfigurational analysis. We demonstrate the transition from isolated to clustering low mobility with decreasing temperature. These slow clusters, whose sizes grow upon cooling, are also associated with concentration fluctuations, characterized by a Zr-enriched phase, with a composition CuZr2 . In addition, a structural analysis of slow clusters based on Voronoi tessellation evidences an increase with respect of the bulk system of the fraction of Cu atoms having a local icosahedral order. These results are in agreement with the consolidated scenario of the relevant role played by icosahedral order in the dynamic slowing-down in supercooled metal alloys.

  1. Time domain reflectometry-measuring dielectric permittivity to detect soil non-acqeous phase liquids contamination-decontamination processes

    Directory of Open Access Journals (Sweden)

    A. Comegna

    2013-09-01

    Full Text Available Contamination of soils with non-aqueous phase liquids (NAPL constitutes a serious geo-environmental problem, given the toxicity level and high mobility of these organic compounds. To develop effective decontamination methods, characterisation and identification of contaminated soils are needed. The objective of this work is to explore the potential of dielectric permittivity measurements to detect the presence of NAPLs in soils. The dielectric permittivity was measured by Time Domain Reflectometry method (TDR in soil samples with either different volumetric content of water (w and NAPL (NAPL or at different stages during immiscible displacement test carried out with two different flushing solutions. A mixing model proposed by Francisca and Montoro, was calibrated to estimate the volume fraction of contaminant present in soil. Obtained results, showed that soil contamination with NAPL and the monitoring of immiscible fluid displacement, during soil remediation processes, can be clearly identified from dielectric measurements.

  2. Isolation of anti-toxin single domain antibodies from a semi-synthetic spiny dogfish shark display library

    Directory of Open Access Journals (Sweden)

    Goldman Ellen R

    2007-11-01

    Full Text Available Abstract Background Shark heavy chain antibody, also called new antigen receptor (NAR, consists of one single Variable domain (VH, containing only two complementarity-determining regions (CDRs. The antigen binding affinity and specificity are mainly determined by these two CDRs. The good solubility, excellent thermal stability and complex sequence variation of small single domain antibodies (sdAbs make them attractive alternatives to conventional antibodies. In this report, we construct and characterize a diversity enhanced semi-synthetic NAR V display library based on naturally occurring NAR V sequences. Results A semi-synthetic shark sdAb display library with a complexity close to 1e9 was constructed. This was achieved by introducing size and sequence variations in CDR3 using randomized CDR3 primers of three different lengths. Binders against three toxins, staphylococcal enterotoxin B (SEB, ricin, and botulinum toxin A (BoNT/A complex toxoid, were isolated from panning the display library. Soluble sdAbs from selected binders were purified and evaluated using direct binding and thermal stability assays on the Luminex 100. In addition, sandwich assays using sdAb as the reporter element were developed to demonstrate their utility for future sensor applications. Conclusion We demonstrated the utility of a newly created hyper diversified shark NAR displayed library to serve as a source of thermal stable sdAbs against a variety of toxins.

  3. Isolation and identification of iron ore-solubilising fungus

    Directory of Open Access Journals (Sweden)

    Damase Khasa

    2010-09-01

    Full Text Available Potential mineral-solubilising fungi were successfully isolated from the surfaces of iron ore minerals. Four isolates were obtained and identified by molecular and phylogenetic methods as close relatives of three different genera, namely Penicillium (for isolate FO, Alternaria (for isolates SFC2 and KFC1 and Epicoccum (for isolate SFC2B. The use of tricalcium phosphate (Ca3(PO42in phosphate-solubilising experiments confirmed isolate FO as the only phosphate solubiliser among the isolated fungi. The bioleaching capabilities of both the fungus and its spent liquid medium were tested and compared using two types of iron ore materials, conglomerate and shale, from the Sishen Iron Ore Mine as sources of potassium (K and phosphorus (P. The spent liquid medium removed more K (a maximum of 32.94% removal, from conglomerate, than the fungus (a maximum of 21.36% removal, from shale. However, the fungus removed more P (a maximum of 58.33% removal, from conglomerate than the spent liquid medium (a maximum of 29.25% removal, from conglomerate. The results also indicated a potential relationship between the removal of K or P and the production of organic acids by the fungus. A high production of gluconic acid could be related to the ability of the fungus to reduce K and P. Acetic, citric and maleic acids were also produced by the fungus, but in lower quantities. In addition, particle size and iron ore type were also shown to have significant effects on the removal of potassium and phosphorus from the iron ore minerals. We therefore conclude that the spent liquid medium from the fungal isolate FO can potentially be used for biobeneficiation of iron ore minerals.

  4. Violations of conservation laws in viscous liquid dynamics

    DEFF Research Database (Denmark)

    Dyre, Jeppe

    2007-01-01

    The laws expressing conservation of momentum and energy apply to any isolated system, but these laws are violated for highly viscous liquids under laboratory conditions because of the unavoidable interactions with the measuring equipment over the long times needed to study the dynamics. Moreover,......, although particle number conservation applies strictly for any liquid, the solidity of viscous liquids implies that even this conservation law is apparently violated in coarse-grained descriptions of density fluctuations.......The laws expressing conservation of momentum and energy apply to any isolated system, but these laws are violated for highly viscous liquids under laboratory conditions because of the unavoidable interactions with the measuring equipment over the long times needed to study the dynamics. Moreover...

  5. Isolation and purification of six iridoid glycosides from gardenia jasminoides fruit by medium-pressure liquid chromatography combined with macroporous resin chromatography.

    Science.gov (United States)

    Wang, Yun; Liu, Hui; Shen, Lifeng; Yao, Lan; Ma, Yinlian; Yu, Dingrong; Chen, Jianhong; Li, Puling; Chen, Ying; Zhang, Cun

    2015-12-01

    Gardeniae fructus is one of the most frequently used herbs in traditional Chinese medicine. In the present study, a process for the enrichment of six iridoid glycosides from Gardeniae fructus was developed using medium-pressure liquid chromatography combined with macroporous resin and reversed-phase chromatography. The purities of different fractions from Gardeniae fructus were assessed using quantitative high-performance liquid chromatography. After fractionation using HPD-100 column chromatography, a 30% ethanol fraction was selected based on high-performance liquid chromatography and liquid chromatography with mass spectrometry qualitative analysis to separate and purify. Based on the orientation analysis results, six compounds-deacetyl asperulosidic acid methyl ester, gardenoside, ixoroside, scandoside methyl ester, genipin-1-O-β-d-gentiobioside, and geniposide-were successfully isolated and purified in three to four combined steps from Gardeniae fructus. The purities of these compounds were found by high-performance liquid chromatography analysis to be 97.9, 98.1, 95.5, 96.3, 97.1, and 98.7%, respectively. Moreover, their structures were elucidated by NMR spectroscopy and liquid chromatography with tandem mass spectrometry. The separation process was highly efficient, rapid, and accurate, making it a potential approach for the large-scale production of iridoids in the laboratory and providing several marker compounds for quality control. This procedure may be meaningful for the purification of other natural products used in traditional Chinese medicine. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Biotransformation of chromium (VI) in liquid effluents by resistant bacteria isolated from the Matanza-Riachuelo basin, in Argentina.

    Science.gov (United States)

    González, Ana Julieta; Caimán, Carolina; Gorino, Natalia; Fortunato, María Susana; Radice, Marcela; Gómez, Carlos; Mujica, Carolina; Marquina, Lorena; Gallego, Alfredo; Korol, Sonia Edith

    2017-10-10

    The aims of this investigation were to evaluate the bacterial resistance to zinc, copper, chromium (VI) and lead in surface water streams from Buenos Aires, Argentina; to select a chromium-resistant strain able to remove the metal in batch process and to evaluate the potential of this strain to remove chromium (VI) in liquid effluents. Bacterial resistance to the metals was evaluated by determining the minimal inhibitory concentration. The kinetic of chromium (VI) removal by one of the resistant strains was studied in nutrient broth with 50 and 100 mg L -1 of the metal, as well as an effluent from an electroplating industry. High resistance to all the metals under study was observed in the bacterial communities of the Matanza-Riachuelo basin. A chromium-resistant strain was isolated and identified as Microbacterium sp. It was able to remove 50 and 100 mg L -1 of Cr (VI) in 36 and 66 h respectively, with efficiency higher than 99%. Experiments with liquid effluents showed the ability of the strain to transform 150 mg L -1 of the metal in 84 h, with efficiency higher than 99%. These results show the potential of this native strain for the treatment of liquid effluents that contain chromium (VI).

  7. Microchannel-flowed-plasma modification of octadecyltrichlorosilane self-assembled-monolayers for liquid crystal alignment

    International Nuclear Information System (INIS)

    Zheng, W.; Chiang, C.-Y.; Underwood, I.

    2013-01-01

    We report that a chemical patterning technique based on local plasma modification of self-assembled monolayers has been utilized to fabricate surfaces for domain liquid crystal alignment. Highly hydrophobic octadecyltrichlorosilane monolayers deposited on glass substrates coated with Indium-Tin-Oxide were brought into contact with elastomeric stamps comprising trenches on a micro scale, and then exposed to an oxygen plasma. In the regions exposed to the plasma the monolayer was etched away leaving a patterned surface that exhibited surface energy differences between surface domains. The surfaces that bear the micropatterns have been shown to be capable of producing patterned alignment of nematic liquid crystal. - Highlights: • Chemical surface-patterning is used to fabricate liquid crystal alignment surface. • Highly hydrophobic octadecyltrichlorosilane monolayer is deposited on substrate. • O 2 plasma flow is used to etch the monolayer to form patterned surface. • The patterned surface exhibits surface energy differences between surface domains. • The surface borne the micropatterns is capable of domain liquid crystal alignment

  8. Faraday instability in deformable domains

    International Nuclear Information System (INIS)

    Pucci, G.

    2013-01-01

    Hydrodynamical instabilities are usually studied either in bounded regions or free to grow in space. In this article we review the experimental results of an intermediate situation, in which an instability develops in deformable domains. The Faraday instability, which consists in the formation of surface waves on a liquid experiencing a vertical forcing, is triggered in floating liquid lenses playing the role of deformable domains. Faraday waves deform the lenses from the initial circular shape and the mutual adaptation of instability patterns with the lens boundary is observed. Two archetypes of behaviour have been found. In the first archetype a stable elongated shape is reached, the wave vector being parallel to the direction of elongation. In the second archetype the waves exceed the response of the lens border and no equilibrium shape is reached. The lens stretches and eventually breaks into fragments that have a complex dynamics. The difference between the two archetypes is explained by the competition between the radiation pressure the waves exert on the lens border and its response due to surface tension.

  9. Ionic liquid foam floatation coupled with ionic liquid dispersive liquid-liquid microextraction for the separation and determination of estrogens in water samples by high-performance liquid chromatography with fluorescence detection.

    Science.gov (United States)

    Zhang, Rui; Wang, Chuanliu; Yue, Qiaohong; Zhou, Tiecheng; Li, Na; Zhang, Hanqi; Hao, Xiaoke

    2014-11-01

    An ionic liquid foam floatation coupled with ionic liquid dispersive liquid-liquid microextraction method was proposed for the extraction and concentration of 17-α-estradiol, 17-β-estradiol-benzoate, and quinestrol in environmental water samples by high-performance liquid chromatography with fluorescence detection. 1-Hexyl-3-methylimidazolium tetrafluoroborate was applied as foaming agent in the foam flotation process and dispersive solvent in microextraction. The introduction of the ion-pairing and salting-out agent NH4 PF6 was beneficial to the improvement of recoveries for the hydrophobic ionic liquid phase and analytes. Parameters of the proposed method including concentration of 1-hexyl-3-methylimidazolium tetrafluoroborate, flow rate of carrier gas, floatation time, types and concentration of ionic liquids, salt concentration in samples, extraction time, and centrifugation time were evaluated. The recoveries were between 98 and 105% with relative standard deviations lower than 7% for lake water and well water samples. The isolation of the target compounds from the water was found to be efficient, and the enrichment factors ranged from 4445 to 4632. This developing method is free of volatile organic solvents compared with regular extraction. Based on the unique properties of ionic liquids, the application of foam floatation, and dispersive liquid-liquid microextraction was widened. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Isolation and Characterization of Antithrombin Peptides from the ...

    African Journals Online (AJOL)

    Purpose: To isolate and characterize the antithrombin compounds of Malaysian leeches' saliva collection (LSC) for use as anticoagulant proteins and peptides. Method: Reversed phase - high performance liquid chromatography (RP-HPLC) was used to isolate all proteins from LSC. All isolated proteins were tested for ...

  11. Isolation and Purification of Planctomycetes associated with Harbor and Lagoon Seagrasses of the Red Sea

    KAUST Repository

    Bream, Holly

    2012-07-01

    Planctomycetes are members of a unique superphylum along with Verrucomicrobia and Chlamydia, situated in the domain Bacteria. They have distinct structural and morphological features, and discoveries made through phylogenetic analysis indicate their important role in nutrient cycling. Their known relationships with marine photosynthetic organisms led to the formation of this study\\'s hypothesis, namely, that Planctomycetes can be isolated from the biofilm of seagrass species of the Red Sea using cultivation techniques adapted for these organisms. Preparation of solid and liquid media using M13 with both agar and gellan, and 2216 Difco Marine Broth full-­ strength, 1/10-­strength, and with antibiotics, resulted in the successful isolation of Planctomycetes as confirmed by morphological examination and transmission electron microscopy. The work performed in this study provides a solid foundation for further studies to elucidate the metabolic pathways and ecological significance of Planctomycetes.

  12. Charged domain-wall dynamics in doped antiferromagnets and spin fluctuations in cuprate superconductors

    International Nuclear Information System (INIS)

    Zaanen, J.; Horbach, M.L.; van Saarloos, W.

    1996-01-01

    Evidence is accumulating that the electron liquid in the cuprate superconductors is characterized by many-hole correlations of the charged magnetic domain-wall type. Here we focus on the strong-coupling limit where all holes are bound to domain walls. We assert that at high temperatures a classical domain-wall fluid is realized and show that the dynamics of such a fluid is characterized by spatial and temporal crossover scales set by temperature itself. The fundamental parameters of this fluid are such that the domain-wall motions dominate the low-frequency spin fluctuations and we derive predictions for the behavior of the dynamical magnetic susceptibility. We argue that a crossover occurs from a high-temperature classical to a low-temperature quantum regime, in direct analogy with helium. We discuss some general characteristics of the domain-wall quantum liquid, realized at low temperatures. copyright 1996 The American Physical Society

  13. Antibacterial activity of vacuum liquid chromatography (VLC) isolated fractions of chloroform extracts of seeds of achyranthes aspera

    International Nuclear Information System (INIS)

    Noor-ul-Amin; Qadir, M.I.; Khan, T.J.; Abbas, G.; Ahmad, B.; Janbaz, K.H.; Ali, M.

    2012-01-01

    Antibacterial activities of locally occurring weed Achyranthes aspera were studied. Three solvents (Hexane, Chloroform, and Ethanol) were used successively for the extraction of active principles from the seeds of this plant. The extracts were concentrated on vacuum rotary evaporator. The concentrated extracts were tested for their antibacterial activities after making their solution in gum acacia. The six bacterial strains used in the antibacterial studies were Bacillus subtilis, Micrococcus luteus, Staphylococcus aureus, Escherichia coli, Pseudomonas aeuroginosa, and Salmonella chloerasuis. Antibacterial activities of the extracts were compared with streptomycin and ampicillin in terms of zones of inhibition. Chloroform and ethanol extracts demonstrated antibacterial activity. Hexane extract did not demonstrate antibacterial activity. Chloroform extract was more potent than alcohol extract in terms of antibacterial activity. An attempt was made to identify the nature of compound by isolation through vacuum liquid chromatography (VLC). The fractions isolated by VLC were subjected to thin layer chromatography (TLC). TLC showed the presence of alkaloids and terpenoids. The active fractions were tested for their antibacterial activity. One of the fractions exhibited antibacterial activity. (author)

  14. Study of the Mechanical Properties and Vibration Isolation Performance of a Molecular Spring Isolator

    Directory of Open Access Journals (Sweden)

    Muchun Yu

    2016-01-01

    Full Text Available Molecular Spring Isolator (MSI is a novel passive vibration isolation technique, providing High-Static-Low-Dynamic (HSLD stiffness based on the use of molecular spring material. The molecular spring material is a solid-liquid mixture consisting of water and hydrophobic nanoporous materials. Under a certain level of external pressure, water molecules can intrude into the hydrophobic pores of nanoporous materials, developing an additional solid-liquid interface. Such interfaces are able to store, release, and transform mechanical energy, providing properties like mechanical spring. Having been only recently developed, the basic mechanic properties of a MSI have not been studied in depth. This paper focuses on the stiffness influence factors, the dynamic frequency response, and the vibration isolation performance of a MSI; these properties help engineers to design MSIs for different engineering applications. First, the working mechanism of a MSI is introduced from a three-dimensional general view of the water infiltration massive hydrophobic nanoporous pores. Next, a wide range of influence factors on the stiffness properties of MSI are studied. In addition, the frequency response functions (FRFs of the MSI vibration isolation system are studied utilizing the matching method based on equivalent piecewise linear (EPL system. Finally, the vibration isolation properties of MSI are evaluated by force transmissibility.

  15. Common-path Fourier domain optical coherence tomography of irradiated human skin and ventilated isolated rabbit lungs

    Science.gov (United States)

    Popp, A.; Wendel, M.; Knels, L.; Knuschke, P.; Mehner, M.; Koch, T.; Boller, D.; Koch, P.; Koch, E.

    2005-08-01

    A compact common path Fourier domain optical coherence tomography (FD-OCT) system based on a broadband superluminescence diode is used for biomedical imaging. The epidermal thickening of human skin after exposure to ultraviolet radiation is measured to proof the feasibility of FD-OCT for future substitution of invasive biopsies in a long term study on natural UV skin protection. The FD-OCT system is also used for imaging lung parenchyma. FD-OCT images of a formalin fixated lung show the same alveolar structure as scanning electron microscopy images. In the ventilated and blood-free perfused isolated rabbit lung FD-OCT is used for real-time cross-sectional image capture of alveolar mechanics throughout tidal ventilation. The alveolar mechanics changing from alternating recruitment-derecruitment at zero positive end-expiratory pressure (PEEP) to persistent recruitment after applying a PEEP of 5 cm H2O is observed in the OCT images.

  16. Strong dielectric liquid crystal polymer (Part 3)

    Energy Technology Data Exchange (ETDEWEB)

    Kurata, Hideaki; Shibasaki, Akira

    1988-11-01

    Influence of change of molecular parameters on liquid crystal condition is studied to get the correlation between molecular structure of liquid crystal and phase structure or visco-elastic properties. Eight kinds of biphenyl type liquid crystals with polyacrilate main chain and triphenyl type liquid crystals were used as samples. Followings were found by a ploarizing microscope and X-ray diffraction: Phases are transferred from isotropic phase S/sub A/ phase S/sup *//sub C/ phase S/sub 1/ phase to solid on temperature desending sequence. Degree of polymerization changes only these transfer point but spacer length affects not only transfer points and layer distance but also liquid crystal structure itself. Visco-elasticity of isotropic phase shows Newtonian viscosity and is affected by the main chain length. Macroscopic and microscopic structures influence on viscoelasticity in S/sub A/ phase and S/sup *//sub C/ phase. Two rapid rises of viscoelasticity are found in low molecular weight liquid crystal when S/sub A/ transfer and S/sub A/ to S/sup *//sub C/ transfer occur by temperature desending from the isotropic phase. Viscoelastic behavior is contributed by the properties of domain itself and interaction between domains, and the interaction is changed by polymerization. 6 references, 13 figures, 1 table.

  17. Fine-tuning of protein domain boundary by minimizing potential coiled coil regions

    International Nuclear Information System (INIS)

    Iwaya, Naoko; Goda, Natsuko; Unzai, Satoru; Fujiwara, Kenichiro; Tanaka, Toshiki; Tomii, Kentaro; Tochio, Hidehito; Shirakawa, Masahiro; Hiroaki, Hidekazu

    2007-01-01

    Structural determination of individual protein domains isolated from multidomain proteins is a common approach in the post-genomic era. Novel and thus uncharacterized domains liberated from intact proteins often self-associate due to incorrectly defined domain boundaries. Self-association results in missing signals, poor signal dispersion and a low signal-to-noise ratio in 1 H- 15 N HSQC spectra. We have found that a putative, non-canonical coiled coil region close to a domain boundary can cause transient hydrophobic self-association and monomer-dimer equilibrium in solution. Here we propose a rational method to predict putative coiled coil regions adjacent to the globular core domain using the program COILS. Except for the amino acid sequence, no preexisting knowledge concerning the domain is required. A small number of mutant proteins with a minimized coiled coil region have been rationally designed and tested. The engineered domains exhibit decreased self-association as assessed by 1 H- 15 N HSQC spectra with improved peak dispersion and sharper cross peaks. Two successful examples of isolating novel N-terminal domains from AAA-ATPases are demonstrated. Our method is useful for the experimental determination of domain boundaries suited for structural genomics studies

  18. Fine-tuning of protein domain boundary by minimizing potential coiled coil regions.

    Science.gov (United States)

    Iwaya, Naoko; Goda, Natsuko; Unzai, Satoru; Fujiwara, Kenichiro; Tanaka, Toshiki; Tomii, Kentaro; Tochio, Hidehito; Shirakawa, Masahiro; Hiroaki, Hidekazu

    2007-01-01

    Structural determination of individual protein domains isolated from multidomain proteins is a common approach in the post-genomic era. Novel and thus uncharacterized domains liberated from intact proteins often self-associate due to incorrectly defined domain boundaries. Self-association results in missing signals, poor signal dispersion and a low signal-to-noise ratio in (1)H-(15)N HSQC spectra. We have found that a putative, non-canonical coiled coil region close to a domain boundary can cause transient hydrophobic self-association and monomer-dimer equilibrium in solution. Here we propose a rational method to predict putative coiled coil regions adjacent to the globular core domain using the program COILS. Except for the amino acid sequence, no preexisting knowledge concerning the domain is required. A small number of mutant proteins with a minimized coiled coil region have been rationally designed and tested. The engineered domains exhibit decreased self-association as assessed by (1)H-(15)N HSQC spectra with improved peak dispersion and sharper cross peaks. Two successful examples of isolating novel N-terminal domains from AAA-ATPases are demonstrated. Our method is useful for the experimental determination of domain boundaries suited for structural genomics studies.

  19. Liquid Marble Coalescence and Triggered Microreaction Driven by Acoustic Levitation.

    Science.gov (United States)

    Chen, Zhen; Zang, Duyang; Zhao, Liang; Qu, Mengfei; Li, Xu; Li, Xiaoguang; Li, Lixin; Geng, Xingguo

    2017-06-27

    Liquid marbles show promising potential for application in the microreactor field. Control of the coalescence between two or among multiple liquid marbles is critical; however, the successful merging of two isolated marbles is difficult because of their mechanically robust particle shells. In this work, the coalescence of multiple liquid marbles was achieved via acoustic levitation. The dynamic behaviors of the liquid marbles were monitored by a high-speed camera. Driven by the sound field, the liquid marbles moved toward each other, collided, and eventually coalesced into a larger single marble. The underlying mechanisms of this process were probed via sound field simulation and acoustic radiation pressure calculation. The results indicated that the pressure gradient on the liquid marble surface favors the formation of a liquid bridge between the liquid marbles, resulting in their coalescence. A preliminary indicator reaction was induced by the coalescence of dual liquid marbles, which suggests that expected chemical reactions can be successfully triggered with multiple reagents contained in isolated liquid marbles via acoustic levitation.

  20. High-temperature phase transitions and domain structures of KLiSO{sub 4}. Studied by polarisation-optics, X-ray topography and liquid-crystal surface decoration

    Energy Technology Data Exchange (ETDEWEB)

    Scherf, Christian; Chung, Su Jin; Hahn, Theo; Klapper, Helmut [RWTH Aachen Univ. (Germany). Inst. fuer Kristallographie; Ivanov, Nicolay R. [Russian Academy of Sciences, Moscow (Russian Federation). Shubnikov Inst. of Crystallography

    2017-07-01

    The transitions between the room temperature phase III (space group P6{sub 3}) and the two high-temperature phases II (Pcmn) and I (P6{sub 3}/mmc) of KLiSO{sub 4} and the domain structures generated by them were investigated by high-temperature polarisation optics (birefringence) and room-temperature X-ray topography, optical activity and nematic-liquid-crystal (NLC) surface decoration. The transition from the polar hexagonal phase III into the centrosymmetric orthorhombic phase II at 708 K leads, due to the loss of the trigonal axis and the radial temperature gradient of the optical heating chamber used, to a roughly hexagonal arrangement of three sets of thin orthorhombic {110} lamelleae with angles of 60 (120 ) between them. The associated twin law ''reflection m{110}{sub orth}'' corresponds to the frequent growth twin m{10 anti 10}{sub hex} of phase III. The domains are easily ferroelastically switched. Upon further heating above 949 K into phase I (P6{sub 3}/mmc) all domains vanish. Upon cooling back into phase II the three domain states related by 60 (120 ) reflections m{110}{sub orth} re-appear, however (due to the higher thermal agitation at 949 K) with a completely different domain structure consisting of many small, irregularly arranged {110}{sub orth} domains. Particular attention is paid to the domain structure of the hexagonal room temperature phase III generated during the re-transition from the orthorhombic phase II. Curiously, from the expected three twin laws inversion anti 1, rotation 2 perpendicular to [001]{sub hex} and reflection m{10 anti 10}{sub hex} only the latter, which corresponds to the frequent growth twinning, has been found. Finally a short treatise of the structural relations of the KLiSO{sub 4} high-temperature polymorphs is given.

  1. Social isolation and cognitive function in Appalachian older adults.

    Science.gov (United States)

    DiNapoli, Elizabeth A; Wu, Bei; Scogin, Forrest

    2014-03-01

    Investigating the relation between social isolation and cognitive function will allow us to identify components to incorporate into cognitive interventions. Data were collected from 267 Appalachian older adults (M = 78.5, range 70-94 years). Overall cognitive functioning and specific cognitive domains were assessed from data of a self-assembled neuropsychological battery of frequently used tasks. Social isolation, social disconnectedness, and perceived isolation were measured from the Lubben Social Network scale-6. Results indicated a significant positive association between all predictor variables (e.g., social isolation, social disconnectedness, and perceived isolation) and outcome variables (e.g., overall cognitive function, memory, executive functioning, attention, and language abilities). Perceived isolation accounted for nearly double the amount of variance in overall cognitive functioning than social disconnectedness (10.2% vs. 5.7%). Findings suggest that social isolation is associated with poorer overall cognitive functioning and this remains true across varied cognitive domains. © The Author(s) 2012.

  2. Liquid metal pump

    International Nuclear Information System (INIS)

    Pennell, W.E.

    1981-01-01

    A liquid metal pump comprising a shaft support structure which is isolated from the pump housing for better preservation of alignment of shaft bearings. The shaft carries an impeller and the support structure carries an impeller cage which is slidably disposed in a diffuser so as to allow complete removal of pump internals for inspection and repair. The diffuser is concentrically supported in the pump housing which also takes up all reaction forces generated by the discharge of the liquid metal from the diffuser, with floating seals arranged between impeller cage and the diffuser. The space between the diffuser and the pump housing permits the incoming liquid to essentially surround the diffuser. (author)

  3. Phytochemical composition of fractions isolated from ten Salvia species by supercritical carbon dioxide and pressurized liquid extraction methods.

    Science.gov (United States)

    Šulniūtė, Vaida; Pukalskas, Audrius; Venskutonis, Petras Rimantas

    2017-06-01

    Ten Salvia species, S. amplexicaulis, S. austriaca, S. forsskaolii S. glutinosa, S. nemorosa, S. officinalis, S. pratensis, S. sclarea, S. stepposa and S. verticillata were fractionated using supercritical carbon dioxide and pressurized liquid (ethanol and water) extractions. Fifteen phytochemicals were identified using commercial standards (some other compounds were identified tentatively), 11 of them were quantified by ultra high pressure chromatography (UPLC) with quadruple and time-of-flight mass spectrometry (Q/TOF, TQ-S). Lipophilic CO 2 extracts were rich in tocopherols (2.36-10.07mg/g), while rosmarinic acid was dominating compound (up to 30mg/g) in ethanolic extracts. Apigenin-7-O-β-d-glucuronide, caffeic and carnosic acids were quantitatively important phytochemicals in the majority other Salvia spp. Antioxidatively active constituents were determined by using on-line high-performance liquid chromatography (HPLC) analysis combined with 2,2'-diphenyl-1-picrylhydrazyl (DPPH) assay (HPLC-DPPH). Development of high pressure isolation process and comprehensive characterisation of phytochemicals in Salvia spp. may serve for their wider applications in functional foods and nutraceuticals. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Determination of sulfonamides in butter samples by ionic liquid magnetic bar liquid-phase microextraction high-performance liquid chromatography.

    Science.gov (United States)

    Wu, Lijie; Song, Ying; Hu, Mingzhu; Xu, Xu; Zhang, Hanqi; Yu, Aimin; Ma, Qiang; Wang, Ziming

    2015-01-01

    A novel, simple, and environmentally friendly pretreatment method, ionic liquid magnetic bar liquid-phase microextraction, was developed for the determination of sulfonamides in butter samples by high-performance liquid chromatography. The ionic liquid magnetic bar was prepared by inserting a stainless steel wire into the hollow of a hollow fiber and immobilizing ionic liquid in the micropores of the hollow fiber. In the extraction process, the ionic liquid magnetic bars were used to stir the mixture of sample and extraction solvent and enrich the sulfonamides in the mixture. After extraction, the analyte-adsorbed ionic liquid magnetic bars were readily isolated with a magnet from the extraction system. It is notable that the present method was environmentally friendly since water and only several microliters of ionic liquid were used in the whole extraction process. Several parameters affecting the extraction efficiency were investigated and optimized, including the type of ionic liquid, sample-to-extraction solvent ratio, the number of ionic liquid magnetic bars, extraction temperature, extraction time, salt concentration, stirring speed, pH of the extraction solvent, and desorption conditions. The recoveries were in the range of 73.25-103.85 % and the relative standard deviations were lower than 6.84 %. The experiment results indicated that the present method was effective for the extraction of sulfonamides in high-fat content samples.

  5. Crystal shapes on striped surface domains

    International Nuclear Information System (INIS)

    Valencia, Antoni

    2004-01-01

    The equilibrium shapes of a simple cubic crystal in contact with a planar chemically patterned substrate are studied theoretically using an effective interface model. The substrate is primarily made of lyophobic material and is patterned with a lyophilic (easily wettable) stripe domain. Three regimes can be distinguished for the equilibrium shapes of the crystal. The transitions between these regimes as the volume of the crystal is changed are continuous or discontinuous depending on the strength of the couplings between the crystal and the lyophilic and lyophobic surface domains. If the crystal grows through a series of states close to equilibrium, the discontinuous transitions correspond to growth instabilities. These transitions are compared with similar results that have been obtained for a volume of liquid wetting a lyophilic stripe domain

  6. Alignment control of columnar liquid crystals with wavelength tunable CO2 laser irradiation

    International Nuclear Information System (INIS)

    Monobe, Hirosato; Awazu, Kunio; Shimizu, Yo

    2008-01-01

    Infrared-induced alignment change with wavelength tunable CO 2 laser irradiation for columnar liquid crystal domains was investigated for a liquid crystalline triphenylene derivative. A uniformly aligned alignment change of domains was observed when a chopped linearly polarized infrared laser light corresponding to the wavelength of the aromatic C-O-C stretching vibration band (9.65 μm) was irradiated. The results strongly imply that the infrared irradiation is a possible technique for device fabrication by use of columnar mesophase as a liquid crystalline semiconductor

  7. Evidence for several dipolar quasi-invariants in liquid crystals

    Science.gov (United States)

    Bonin, C. J.; González, C. E.; Segnorile, H. H.; Zamar, R. C.

    2013-10-01

    The quasi-equilibrium states of an observed quantum system involve as many constants of motion as the dimension of the operator basis which spans the blocks of all the degenerate eigenvalues of the Hamiltonian that drives the system dynamics, however, the possibility of observing such quasi-invariants in solid-like spin systems in Nuclear Magnetic Resonance (NMR) is not a strictly exact prediction. The aim of this work is to provide experimental evidence of several quasi-invariants, in the proton NMR of small spin clusters, like nematic liquid crystal molecules, in which the use of thermodynamic arguments is not justified. We explore the spin states prepared with the Jeener-Broekaert pulse sequence by analyzing the time-domain signals yielded by this sequence as a function of the preparation times, in a variety of dipolar networks, solids, and liquid crystals. We observe that the signals can be explained with two dipolar quasi-invariants only within a range of short preparation times, however at longer times liquid crystal signals show an echo-like behaviour whose description requires assuming more quasi-invariants. We study the multiple quantum coherence content of such signals on a basis orthogonal to the z-basis and see that such states involve a significant number of correlated spins. Therefore, we show that the NMR signals within the whole preparation time-scale can only be reconstructed by assuming the occurrence of multiple quasi-invariants which we experimentally isolate.

  8. Resistance to linezolid in Staphylococcus spp. clinical isolates associated with ribosomal binding site modifications: novel mutation in domain V of 23S rRNA.

    Science.gov (United States)

    Musumeci, Rosario; Calaresu, Enrico; Gerosa, Jolanda; Oggioni, Davide; Bramati, Simone; Morelli, Patrizia; Mura, Ida; Piana, Andrea; Are, Bianca Maria; Cocuzza, Clementina Elvezia

    2016-10-01

    Linezolid is the main representative of the oxazolidinones, introduced in 2000 in clinical practice to treat severe Gram-positive infections. This compound inhibits protein synthesis by binding to the peptidyl transferase centre of the 50S bacterial ribosomal subunit. The aim of this study was to characterize 12 clinical strains of linezolid-resistant Staphylococcus spp. isolated in Northern Italy. All isolates of Staphylococcus spp. studied showed a multi-antibiotic resistance phenotype. In particular, all isolates showed the presence of the mecA gene associated with SSCmec types IVa, V or I. Mutations in domain V of 23S rRNA were shown to be the most prevalent mechanism of linezolid resistance: among these a new C2551T mutation was found in S. aureus, whilst the G2576T mutation was shown to be the most prevalent overall. Moreover, three S. epidermidis isolates were shown to have linezolid resistance associated only with alterations in both L3 and L4 ribosomal proteins. No strain was shown to harbor the previously described cfr gene. These results have shown how the clinical use of linezolid in Northern Italy has resulted in the selection of multiple antibiotic-resistant clinical isolates of Staphylococcus spp., with linezolid resistance in these strains being associated with mutations in 23S rRNA or ribosomal proteins L3 and L4.

  9. Backflush HPLC for the isolation of polycyclic aromatic compounds - a comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Oestman, C.E.; Colmsjoe, A.L.

    1987-12-01

    Semipreparative HPLC utilizing a polar bonded phase was applied to the isolation of polycyclic aromatic compounds (PAC) from complex samples using a backflush technique. Aminopropyl- and cyanopropyl-modified silica was tested. Aminopropyl-modified silica was found to be superior in achieving rapid, selective and non discriminating isolation of PAC. This was compared with the most commonly used isolation methods, dimethylsulfoxide (DMSO), dimethylformamide (DMF) and nitromethane liquid-liquid extractions, and silica and SephadexLH-20 open column chromatography. Strong discrimination of alkylated PAC and polycyclic aromatic nitrogen heterocyclics (PANH) was found for the liquid-liquid extractions and the LH-20 column chromatography. These comparisons were made using both standard compounds and a sample of used crank-case oil, indicating the necessity of using a real sample for evaluation of extraction methods. Recoveries of 42 PACs are reported.

  10. Phase Behavior and Domain Size in Sphingomyelin-Containing Lipid Bilayers

    Science.gov (United States)

    Petruzielo, Robin S.; Heberle, Frederick A.; Drazba, Paul; Katsaras, John; Feigenson, Gerald W.

    2013-01-01

    Membrane raft size measurements are crucial to understanding the stability and functionality of rafts in cells. The challenge of accurately measuring raft size is evidenced by the disparate reports of domain sizes, which range from nanometers to microns for the ternary model membrane system sphingomyelin (SM)/1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC)/cholesterol (Chol). Using Förster resonance energy transfer (FRET) and differential scanning calorimetry (DSC), we established phase diagrams for porcine brain SM (bSM)/dioleoyl-sn-glycero-3-phosphocholine (DOPC)/Chol and bSM/POPC/Chol at 15 and 25°C. By combining two techniques with different spatial sensitivities, namely FRET and small-angle neutron scattering (SANS), we have significantly narrowed the uncertainty in domain size estimates for bSM/POPC/Chol mixtures. Compositional trends in FRET data revealed coexisting domains at 15 and 25°C for both mixtures, while SANS measurements detected no domain formation for bSM/POPC/Chol. Together these results indicate that liquid domains in bSM/POPC/Chol are between 2 and 7 nm in radius at 25°C: that is, domains must be on the order of the 2–6 nm Förster distance of the FRET probes, but smaller than the ~7 nm minimum cluster size detectable with SANS. However, for palmitoyl SM (PSM)/POPC/Chol at a similar composition, SANS detected coexisting liquid domains. This increase in domain size upon replacing the natural SM component (which consists of a mixture of chain lengths) with synthetic PSM, suggests a role for SM chain length in modulating raft size in vivo. PMID:23337475

  11. Solution processing of polymer semiconductor: Insulator blends-Tailored optical properties through liquid-liquid phase separation control

    KAUST Repository

    Hellmann, Christoph; Treat, Neil D.; Scaccabarozzi, Alberto D.; Razzell Hollis, Joseph; Fleischli, Franziska D.; Bannock, James H.; de Mello, John; Michels, Jasper J.; Kim, Ji-Seon; Stingelin, Natalie

    2014-01-01

    © 2014 Wiley Periodicals, Inc. It has been demonstrated that the 0-0 absorption transition of poly(3-hexylthiophene) (P3HT) in blends with poly(ethylene oxide) (PEO) could be rationally tuned through the control of the liquid-liquid phase separation process during solution deposition. Pronounced J-like aggregation behavior, characteristic for systems of a low exciton band width, was found for blends where the most pronounced liquid-liquid phase separation occurred in solution, leading to domains of P3HT and PEO of high phase purity. Since liquid-liquid phase separation could be readily manipulated either by the solution temperature, solute concentration, or deposition temperature, to name a few parameters, our findings promise the design from the out-set of semiconductor:insulator architectures of pre-defined properties by manipulation of the interaction parameter between the solutes as well as the respective solute:solvent system using classical polymer science principles.

  12. Solution processing of polymer semiconductor: Insulator blends-Tailored optical properties through liquid-liquid phase separation control

    KAUST Repository

    Hellmann, Christoph

    2014-12-17

    © 2014 Wiley Periodicals, Inc. It has been demonstrated that the 0-0 absorption transition of poly(3-hexylthiophene) (P3HT) in blends with poly(ethylene oxide) (PEO) could be rationally tuned through the control of the liquid-liquid phase separation process during solution deposition. Pronounced J-like aggregation behavior, characteristic for systems of a low exciton band width, was found for blends where the most pronounced liquid-liquid phase separation occurred in solution, leading to domains of P3HT and PEO of high phase purity. Since liquid-liquid phase separation could be readily manipulated either by the solution temperature, solute concentration, or deposition temperature, to name a few parameters, our findings promise the design from the out-set of semiconductor:insulator architectures of pre-defined properties by manipulation of the interaction parameter between the solutes as well as the respective solute:solvent system using classical polymer science principles.

  13. Effect of immobile isolated enzymes from rumen liquid by using alginate matrices on the bay leaf extraction

    Science.gov (United States)

    Paramita, Vita; Yulianto, Mohammad Endy; Yohana, Eflita; Arifan, Fahmi; Hanifah, Amjad, Muhammad Taqiyuddin

    2015-12-01

    This research aims to develop the enzymatically of bay leaves phytochemical extraction process. The novelty and the main innovations of this research is the development of extraction process by using enzymatic extractor and isolate the enzymes from rumen liquid to shift the equilibrium phase, increase the extraction rate and increase the extraction yield. The activity of rumen liquid enzyme was represented by the activity of cellulase and protease. The analyze of total flavonoid content was performed by using UV-Vis Spectrofometry. The activity of immobilized enzyme of cellulase (0.08±0.00 U/ml) was lower than the un-immobilized one (0.23±0.00 U/ml). However, there was no difference activity of the immobilized (0.75±0.00 U/ml) and un-immobilized (0.76±0.01 U/ml) of protease. The model of mass transfer of un-immobilized enzyme can be fitted on the experimental data, however the model of mass transfer of immobilized enzyme did not match with the experimental data. The mass transfer coefficient of enzymatic extraction flavonoids bay leaf without immobilization was 0.17167 s-1 which greater than the reported value of obtained KLa from extraction by using electric heating.

  14. Direct time-domain techniques for transient radiation and scattering

    International Nuclear Information System (INIS)

    Miller, E.K.; Landt, J.A.

    1976-01-01

    A tutorial introduction to transient electromagnetics, focusing on direct time-domain techniques, is presented. Physical, mathematical, numerical, and experimental aspects of time-domain methods, with emphasis on wire objects excited as antennas or scatters are examined. Numerous computed examples illustrate the characteristics of direct time-domain procedures, especially where they may offer advantages over procedures in the more familiar frequency domain. These advantages include greater solution efficiency for many types of problems, the ability to handle nonlinearities, improved physical insight and interpretability, availability of wide-band information from a single calculation, and the possibility of isolating interactions among various parts of an object using time-range gating

  15. A design study for the isolation of the 281-3H retention basin at the Savannah River Site using the viscous liquid barrier technology

    International Nuclear Information System (INIS)

    Moridis, G.J.; Persoff, P.; Apps, J.; James, A.; Oldenburg, C.; McGrath, A.; Myer, L.; Pellerin, L.; Pruess, K.

    1996-11-01

    This report is a description of the design study for a pilot-scale field demonstration of the Viscous Liquid Barrier (VLB) technology, a new subsurface containment technology for waste isolation using a new generation of barrier liquids. The demonstration site was Retention Basin 281-3H, a shallow catchment basin at the Savannah River Site, which is contaminated mainly by radionuclides ( 137 Cs, 90 Sr, and 238 Pu). The goals of the field demonstration were (a) to demonstrate the ability to create a continuous subsurface barrier in order to isolate the contaminants, and (b) to demonstrate the continuity, performance, and integrity of the barrier. The site was characterized, and preliminary hydraulic conductivity data were obtained from core samples. Based on the site characteristics and the functional requirements, a conceptual model was developed, the barrier specifications were defined, and lance injection was selected as the emplacement method. The injection strategy for the subsurface conditions at the site was determined using numerical simulations. An appropriate variant of Colloidal Silica (CS) was selected as the barrier liquid based on its relative insensitivity to interactions with the site soils, and the formulation for optimum site performance was determined. A barrier verification strategy, including hydraulic, pneumatic, tracer, and geophysical methods, was developed. A lance water injection test was conducted in order to obtain representative estimates of the hydraulic conductivity and its distribution for the design of the barrier emplacement. The water injection test demonstrated the lack of permeable zones for CS injection, and a decision not to proceed with the barrier emplacement was reached

  16. General and selective isolation procedure for high-performance liquid chromatographic determination of anabolic steroids in tissues.

    Science.gov (United States)

    Laganà, A; Marino, A

    1991-12-27

    A multi-residue method has been developed for the determination of anabolic steroids in animal tissue. The analytes are extracted from tissue with methanol and the extract is subjected to two solid-phase extractions, one using a non-specific adsorbing material, such as graphitized carbon black (Carbopack B), and the other Amberlite CG-400 I in the OH form. This procedure allowed the neutral anabolics (testosterone, trenbolone and progesterone) to be isolated and separated from the acidic type (phenolic group), such as diethylstilbestrol, oestradiol, zeranol/zearalenone and their respective metabolites. The determination was effected using high-performance liquid chromatography with different detectors (ultraviolet, fluorimetric and electrochemical). Several analytical parameters were studied: chromatographic conditions, recoveries, evaporation step, solvent flow-rate, cartridges reusability, interference of plastic cartridges. For all the anabolics investigated the recoveries were greater than 83.6%.

  17. Spatial heterogeneity in liquid–liquid phase transition

    International Nuclear Information System (INIS)

    Duan Yun-Rui; Li Tao; Wu Wei-Kang; Li Jie; Zhou Xu-Yan; Liu Si-Da; Li Hui

    2017-01-01

    Molecular dynamics simulations are performed to investigate the liquid–liquid phase transition (LLPT) and the spatial heterogeneity in Al–Pb monotectic alloys. The results reveal that homogeneous liquid Al–Pb alloy undergoes an LLPT, separating into Al-rich and Pb-rich domains, which is quite different from the isocompositional liquid water with a transition between low-density liquid (LDL) and high-density liquid (HDL). With spatial heterogeneity becoming large, LLPT takes place correspondingly. The relationship between the cooling rate, relaxation temperature and percentage of Al and the spatial heterogeneity is also reported. This study may throw light on the relationship between the structure heterogeneity and LLPT, which provides novel strategies to control the microstructures in the fabrication of the material with high performance. (paper)

  18. Microphase separation and the formation of ion conductivity channels in poly(ionic liquid)s: A coarse-grained molecular dynamics study

    Science.gov (United States)

    Weyman, Alexander; Bier, Markus; Holm, Christian; Smiatek, Jens

    2018-05-01

    We study generic properties of poly(ionic liquid)s (PILs) via coarse-grained molecular dynamics simulations in bulk solution and under confinement. The influence of different side chain lengths on the spatial properties of the PIL systems and on the ionic transport mechanism is investigated in detail. Our results reveal the formation of apolar and polar nanodomains with increasing side chain length in good agreement with previous results for molecular ionic liquids. The ion transport numbers are unaffected by the occurrence of these domains, and the corresponding values highlight the potential role of PILs as single-ion conductors in electrochemical devices. In contrast to bulk behavior, a pronounced formation of ion conductivity channels in confined systems is initiated in close vicinity to the boundaries. We observe higher ion conductivities in these channels for increasing PIL side chain lengths in comparison with bulk values and provide an explanation for this effect. The appearance of these domains points to an improved application of PILs in modern polymer electrolyte batteries.

  19. Time Domain View of Liquid-like Screening and Large Polaron Formation in Lead Halide Perovskites

    Science.gov (United States)

    Joshi, Prakriti Pradhan; Miyata, Kiyoshi; Trinh, M. Tuan; Zhu, Xiaoyang

    The structural softness and dynamic disorder of lead halide perovskites contributes to their remarkable optoelectronic properties through efficient charge screening and large polaron formation. Here we provide a direct time-domain view of the liquid-like structural dynamics and polaron formation in single crystal CH3NH3PbBr3 and CsPbBr3 using femtosecond optical Kerr effect spectroscopy in conjunction with transient reflectance spectroscopy. We investigate structural dynamics as function of pump energy, which enables us to examine the dynamics in the absence and presence of charge carriers. In the absence of charge carriers, structural dynamics are dominated by over-damped picosecond motions of the inorganic PbBr3- sub-lattice and these motions are strongly coupled to band-gap electronic transitions. Carrier injection from across-gap optical excitation triggers additional 0.26 ps dynamics in CH3NH3PbBr3 that can be attributed to the formation of large polarons. In comparison, large polaron formation is slower in CsPbBr3 with a time constant of 0.6 ps. We discuss how such dynamic screening protects charge carriers in lead halide perovskites. US Department of Energy, Office of Science - Basic Energy Sciences.

  20. Model and Simulation of a Tunable Birefringent Fiber Using Capillaries Filled with Liquid Ethanol for Magnetic Quasiphase Matching In-Fiber Isolator

    Directory of Open Access Journals (Sweden)

    Clint Zeringue

    2010-01-01

    Full Text Available A technique to tune a magnetic quasi-phase matching in-fiber isolator through the application of stress induced by two mutually orthogonal capillary tubes filled with liquid ethanol is investigated numerically. The results show that it is possible to “tune” the birefringence in these fibers over a limited range depending on the temperature at which the ethanol is loaded into the capillaries. Over this tuning range, the thermal sensitivity of the birefringence is an order-of-magnitude lower than conventional fibers, making this technique well suited for magnetic quasi-phase matching.

  1. The homeodomain derived peptide Penetratin induces curvature of fluid membrane domains.

    Directory of Open Access Journals (Sweden)

    Antonin Lamazière

    Full Text Available BACKGROUND: Protein membrane transduction domains that are able to cross the plasma membrane are present in several transcription factors, such as the homeodomain proteins and the viral proteins such as Tat of HIV-1. Their discovery resulted in both new concepts on the cell communication during development, and the conception of cell penetrating peptide vectors for internalisation of active molecules into cells. A promising cell penetrating peptide is Penetratin, which crosses the cell membranes by a receptor and metabolic energy-independent mechanism. Recent works have claimed that Penetratin and similar peptides are internalized by endocytosis, but other endocytosis-independent mechanisms have been proposed. Endosomes or plasma membranes crossing mechanisms are not well understood. Previously, we have shown that basic peptides induce membrane invaginations suggesting a new mechanism for uptake, "physical endocytosis". METHODOLOGY/PRINCIPAL FINDINGS: Herein, we investigate the role of membrane lipid phases on Penetratin induced membrane deformations (liquid ordered such as in "raft" microdomains versus disordered fluid "non-raft" domains in membrane models. Experimental data show that zwitterionic lipid headgroups take part in the interaction with Penetratin suggesting that the external leaflet lipids of cells plasma membrane are competent for peptide interaction in the absence of net negative charges. NMR and X-ray diffraction data show that the membrane perturbations (tubulation and vesiculation are associated with an increase in membrane negative curvature. These effects on curvature were observed in the liquid disordered but not in the liquid ordered (raft-like membrane domains. CONCLUSIONS/SIGNIFICANCE: The better understanding of the internalisation mechanisms of protein transduction domains will help both the understanding of the mechanisms of cell communication and the development of potential therapeutic molecular vectors. Here we

  2. Rapid characterisation of Klebsiella oxytoca isolates from contaminated liquid hand soap using mass spectrometry, FTIR and Raman spectroscopy.

    Science.gov (United States)

    Dieckmann, Ralf; Hammerl, Jens Andre; Hahmann, Hartmut; Wicke, Amal; Kleta, Sylvia; Dabrowski, Piotr Wojciech; Nitsche, Andreas; Stämmler, Maren; Al Dahouk, Sascha; Lasch, Peter

    2016-06-23

    Microbiological monitoring of consumer products and the efficiency of early warning systems and outbreak investigations depend on the rapid identification and strain characterisation of pathogens posing risks to the health and safety of consumers. This study evaluates the potential of three rapid analytical techniques for identification and subtyping of bacterial isolates obtained from a liquid hand soap product, which has been recalled and reported through the EU RAPEX system due to its severe bacterial contamination. Ten isolates recovered from two bottles of the product were identified as Klebsiella oxytoca and subtyped using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI TOF MS), near-infrared Fourier transform (NIR FT) Raman spectroscopy and Fourier transform infrared (FTIR) spectroscopy. Comparison of the classification results obtained by these phenotype-based techniques with outcomes of the DNA-based methods pulsed-field gel electrophoresis (PFGE), multi-locus sequence typing (MLST) and single nucleotide polymorphism (SNP) analysis of whole-genome sequencing (WGS) data revealed a high level of concordance. In conclusion, a set of analytical techniques might be useful for rapid, reliable and cost-effective microbial typing to ensure safe consumer products and allow source tracking.

  3. NMR structural and dynamical investigation of the isolated voltage-sensing domain of the potassium channel KvAP: implications for voltage gating.

    Science.gov (United States)

    Shenkarev, Zakhar O; Paramonov, Alexander S; Lyukmanova, Ekaterina N; Shingarova, Lyudmila N; Yakimov, Sergei A; Dubinnyi, Maxim A; Chupin, Vladimir V; Kirpichnikov, Mikhail P; Blommers, Marcel J J; Arseniev, Alexander S

    2010-04-28

    The structure and dynamics of the isolated voltage-sensing domain (VSD) of the archaeal potassium channel KvAP was studied by high-resolution NMR. The almost complete backbone resonance assignment and partial side-chain assignment of the (2)H,(13)C,(15)N-labeled VSD were obtained for the protein domain solubilized in DPC/LDAO (2:1) mixed micelles. Secondary and tertiary structures of the VSD were characterized using secondary chemical shifts and NOE contacts. These data indicate that the spatial structure of the VSD solubilized in micelles corresponds to the structure of the domain in an open state of the channel. NOE contacts and secondary chemical shifts of amide protons indicate the presence of tightly bound water molecule as well as hydrogen bond formation involving an interhelical salt bridge (Asp62-R133) that stabilizes the overall structure of the domain. The backbone dynamics of the VSD was studied using (15)N relaxation measurements. The loop regions S1-S2 and S2-S3 were found mobile, while the S3-S4 loop (voltage-sensor paddle) was found stable at the ps-ns time scale. The moieties of S1, S2, S3, and S4 helices sharing interhelical contacts (at the level of the Asp62-R133 salt bridge) were observed in conformational exchange on the micros-ms time scale. Similar exchange-induced broadening of characteristic resonances was observed for the VSD solubilized in the membrane of lipid-protein nanodiscs composed of DMPC, DMPG, and POPC/DOPG lipids. Apparently, the observed interhelical motions represent an inherent property of the VSD of the KvAP channel and can play an important role in the voltage gating.

  4. Revealing molecular-level surface structure of amyloid fibrils in liquid by means of frequency modulation atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Fukuma, Takeshi [Frontier Science Organization, Kanazawa University, Kakuma-machi, Kanazawa 920-1192 (Japan); Mostaert, Anika S; Jarvis, Suzanne P [Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Republic of Ireland (Ireland); Serpell, Louise C [Department of Biochemistry, University of Sussex, John Maynard Building, Falmer BN1 9QG (United Kingdom)], E-mail: fukuma@staff.kanazawa-u.ac.jp, E-mail: Anika.Mostaert@ucd.ie, E-mail: L.C.Serpell@sussex.ac.uk, E-mail: Suzi.Jarvis@ucd.ie

    2008-09-24

    We have investigated the surface structure of islet amyloid polypeptide (IAPP) fibrils and {alpha}-synuclein protofibrils in liquid by means of frequency modulation atomic force microscopy (FM-AFM). Angstroem-resolution FM-AFM imaging of isolated macromolecules in liquid is demonstrated for the first time. Individual {beta}-strands aligned perpendicular to the fibril axis with a spacing of 0.5 nm are resolved in FM-AFM images, which confirms cross-{beta} structure of IAPP fibrils in real space. FM-AFM images also reveal the existence of 4 nm periodic domains along the axis of IAPP fibrils. Stripe features with 0.5 nm spacing are also found in images of {alpha}-synuclein protofibrils. However, in contrast to the case for IAPP fibrils, the stripes are oriented 30 deg. from the axis, suggesting the possibility of {beta}-strand alignment in protofibrils different from that in mature fibrils or the regular arrangement of thioflavin T molecules present during the fibril preparation aligned at the surface of the protofibrils.

  5. Revealing molecular-level surface structure of amyloid fibrils in liquid by means of frequency modulation atomic force microscopy

    International Nuclear Information System (INIS)

    Fukuma, Takeshi; Mostaert, Anika S; Jarvis, Suzanne P; Serpell, Louise C

    2008-01-01

    We have investigated the surface structure of islet amyloid polypeptide (IAPP) fibrils and α-synuclein protofibrils in liquid by means of frequency modulation atomic force microscopy (FM-AFM). Angstroem-resolution FM-AFM imaging of isolated macromolecules in liquid is demonstrated for the first time. Individual β-strands aligned perpendicular to the fibril axis with a spacing of 0.5 nm are resolved in FM-AFM images, which confirms cross-β structure of IAPP fibrils in real space. FM-AFM images also reveal the existence of 4 nm periodic domains along the axis of IAPP fibrils. Stripe features with 0.5 nm spacing are also found in images of α-synuclein protofibrils. However, in contrast to the case for IAPP fibrils, the stripes are oriented 30 deg. from the axis, suggesting the possibility of β-strand alignment in protofibrils different from that in mature fibrils or the regular arrangement of thioflavin T molecules present during the fibril preparation aligned at the surface of the protofibrils

  6. Bile acids modulate signaling by functional perturbation of plasma membrane domains.

    Science.gov (United States)

    Zhou, Yong; Maxwell, Kelsey N; Sezgin, Erdinc; Lu, Maryia; Liang, Hong; Hancock, John F; Dial, Elizabeth J; Lichtenberger, Lenard M; Levental, Ilya

    2013-12-13

    Eukaryotic cell membranes are organized into functional lipid and protein domains, the most widely studied being membrane rafts. Although rafts have been associated with numerous plasma membrane functions, the mechanisms by which these domains themselves are regulated remain undefined. Bile acids (BAs), whose primary function is the solubilization of dietary lipids for digestion and absorption, can affect cells by interacting directly with membranes. To investigate whether these interactions affected domain organization in biological membranes, we assayed the effects of BAs on biomimetic synthetic liposomes, isolated plasma membranes, and live cells. At cytotoxic concentrations, BAs dissolved synthetic and cell-derived membranes and disrupted live cell plasma membranes, implicating plasma membrane damage as the mechanism for BA cellular toxicity. At subtoxic concentrations, BAs dramatically stabilized domain separation in Giant Plasma Membrane Vesicles without affecting protein partitioning between coexisting domains. Domain stabilization was the result of BA binding to and disordering the nonraft domain, thus promoting separation by enhancing domain immiscibility. Consistent with the physical changes observed in synthetic and isolated biological membranes, BAs reorganized intact cell membranes, as evaluated by the spatial distribution of membrane-anchored Ras isoforms. Nanoclustering of K-Ras, related to nonraft membrane domains, was enhanced in intact plasma membranes, whereas the organization of H-Ras was unaffected. BA-induced changes in Ras lateral segregation potentiated EGF-induced signaling through MAPK, confirming the ability of BAs to influence cell signal transduction by altering the physical properties of the plasma membrane. These observations suggest general, membrane-mediated mechanisms by which biological amphiphiles can produce their cellular effects.

  7. Social isolation in mental health: a conceptual and methodological review.

    Science.gov (United States)

    Wang, Jingyi; Lloyd-Evans, Brynmor; Giacco, Domenico; Forsyth, Rebecca; Nebo, Cynthia; Mann, Farhana; Johnson, Sonia

    2017-12-01

    Social isolation and related concepts have been discussed increasingly in the field of mental health. Despite this, there is a lack of conceptual clarity and consistency in the definition and operationalisation of these terms. This review aimed to provide a clear framework for social isolation and related concepts, and to identify well-established measures in the field of mental health for each conceptual domain discussed. We used an iterative strategy of expert consultation and literature searching. A multi-disciplinary group of senior academics was consulted both before and after the literature searching to identify relevant terms, conceptual papers, or recommended measures. Our conceptual framework was also validated through expert consultation. We searched the Web of Science database using terms suggested by experts and subsequently identified further relevant studies through review articles and by reading full texts and reference lists of included studies. A narrative synthesis was conducted. We developed a model with five domains incorporating all the concepts relevant to social isolation in regular use in the mental health research literature. These five domains are: social network-quantity; social network-structure; social network-quality; appraisal of relationships-emotional; and appraisal of relationships-resources. We also identified well-developed measures suitable for assessing each of the five conceptual domains or covering multi-domains. Our review proposes a conceptual model to encompass and differentiate all terms relating to social isolation. Potential uses are in allowing researchers and intervention developers to identify precisely the intended outcomes of interventions, and to choose the most appropriate measures to use in mental health settings.

  8. Full molecular dynamics simulations of liquid water and carbon tetrachloride for two-dimensional Raman spectroscopy in the frequency domain

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Ju-Yeon, E-mail: ju8879@kuchem.kyoto-u.ac.jp; Ito, Hironobu, E-mail: h.ito@kuchem.kyoto-u.ac.jp; Tanimura, Yoshitaka, E-mail: tanimura@kuchem.kyoto-u.ac.jp

    2016-12-20

    Frequency-domain two-dimensional (2D) Raman signals, which are equivalent to coherent two-dimensional Raman scattering (COTRAS) signals, for liquid water and carbon tetrachloride were calculated using an equilibrium–nonequilibrium hybrid molecular dynamics (MD) simulation algorithm. An appropriate representation of the 2D Raman spectrum obtained from MD simulations provides an easy-to-understand depiction of structural and dynamical properties. We elucidate mechanisms governing the 2D signal profiles involving anharmonic mode–mode coupling and the nonlinearities of the polarizability for the intermolecular and intramolecular vibrational modes. The predicted signal profiles and intensities can be utilized to analyze recently developed single-beam 2D spectra, whose signals are generated from a coherently controlled pulse, allowing the single-beam measurement to be carried out more efficiently. Moreover, the MD simulation results allow us to visualize the molecular structure and dynamics by comparing the accurately calculated spectrum with experimental result.

  9. Membrane Restructuring by Phospholipase A2 Is Regulated by the Presence of Lipid Domains

    DEFF Research Database (Denmark)

    Leidy, Chad; Ocampo, Jackson; Duelund, Lars

    2011-01-01

    Secretory phospholipase A2 (sPLA2) catalyzes the hydrolysis of glycerophospholipids. This enzyme is sensitive to membrane structure, and its activity has been shown to increase in the presence of liquid-crystalline/gel (Lα/Lβ) lipid domains. In this work, we explore whether lipid domains can also...... without necessarily destroying the membrane. We confirm by high-performance liquid chromatography the preferential hydrolysis of DMPC within the phase coexistence region of the DMPC/DSPC phase diagram, showing that this preferential hydrolysis is accentuated close to the solidus phase boundary...

  10. The Study of Isolated Bacteria Application for Bioremediation Agent of Uranium Radionuclide in the Environment

    International Nuclear Information System (INIS)

    Yazid, Mochd

    2007-01-01

    Application of the isolated bacteria on the Low Level Uranium Waste as uranium bioremediation agent in the environment has been studied. The objective of this research is to study the possibility of isolated bacteria to be used on uranium remediation process. The isolation of uranium resistance bacteria was carried out on the selective medium SBS containing 10 mg/l uranium, incubated at 37°C until the growth was visible. Selection of binding uranium bacteria was carried out based on their ability to grow on liquid medium containing various concentration of uranium that shacked on 120 rpm speed. The isolated bacteria with the highest specific growth rate constant (μ) were selected for biochemical characterization and identification by matching profile method. The result of this research showed that three selected isolate bacteria were able to grow well on liquid SBS medium until 100 mg/l uranium concentration. The identification results showed that two of them were suspected belong to the genus Pseudomonas and one isolates belong to the genus of Bacillus. The uranium reduction studied was performed by growing up the isolated bacteria on the SBS liquid medium that containing 40 mg/l uranium. Bacterial growth were measured by weighted of bacterial biomass and uranium concentration were measured by spectrophotometer. The research result showed that the selected isolates bacteria may applicable for bioremediation agent because of their ability to grow well on liquid SBS medium and their ability on uranium concentration reduction. The efficiency of reduction by Pseudomonas in the isolated bacteria one were 78.51 % and in the isolated bacteria three were 91.47 % , and Bacillus in the isolate bacteria six were 52.73%. (author)

  11. Archive-cup insert for liquid-metal sampling

    International Nuclear Information System (INIS)

    Nelson, P.A.; Kolba, V.M.; Filewicz, E.C.; Holmes, J.T.

    1975-01-01

    An insert for collecting liquid-metal samples within a vertical casing including an elongated housing with an upper and a lower overflow seal of annular shape is described. The lower seal includes a centrally located pedestal on which a sample cup is disposed. Liquid metal enters the annulus of the upper seal and overflows into the cup which fills and overflows into the lower seal. Liquid-metal overflow from the lower seal is discharged from the insert. On cooling, the liquid metal trapped within the seals solidifies to hermetically isolate the metal sample within the cup. The device is particularly applicable for use with sampling systems on liquid metal-cooled reactors. (U.S.)

  12. Molecular cloning of cellulase genes from indigenous bacterial isolates

    International Nuclear Information System (INIS)

    Jong Bor Chyan; Pauline Liew Woan Ying; Mat Rasol Awang

    2006-01-01

    Indigenous cellulolytic bacterial isolates having high activities in degrading carboxymethyl cellulose (CMC) were isolated from local environments. Identification of these isolates were performed by molecular techniques. By using polymerase chain reaction (PCR) techniques, PCR products encoding cellulase gene were amplified from the total genomic DNAs. Purified PCR product was successfully cloned and expressed in Escherichia coli host system. The complete nucleotide sequences of the cellulase genes determined. The analysis of amino acid sequences deduced from the genes indicated that the cloned DNA fragments show high homology to those of endoglucanase genes of family GH5. All cloned genes consist of an N-terminal signal peptide, a catalytic domain of family 5 glycosyl hydrolase and a cellulose-binding domain of family III. (Author)

  13. A polysaccharide isolated from the liquid culture of Lentinus edodes (shiitake) mushroom mycelia containing black rice bran protects mice against Salmonellosis through up-regulation of the Th1 immune reaction

    Science.gov (United States)

    The present study investigated the antibacterial effect of a bioprocessed polysaccharide (BPP) isolated from Lentinus edodes liquid mycelial culture supplemented with black rice bran against murine salmonellosis. BPP was not bactericidal in vitro, but did, however stimulate uptake of the bacteria i...

  14. Criteria: waste tank isolation and stabilization

    Energy Technology Data Exchange (ETDEWEB)

    Metz, W.P.; Ogren, W.E.

    1976-09-01

    The crystallized Hanford high-level wastes stored in single-shell underground tanks consist of sludges and salt cakes covered with supernatural liquor. Purpose of stabilization and isolation is to reduce the releases and losses as a result of a loss of tank integrity. The tanks will be modified so that no inadvertent liquid additions can be made. Criteria for the isolation and stabilization are given and discussed briefly. (DLC)

  15. Criteria: waste tank isolation and stabilization

    International Nuclear Information System (INIS)

    Metz, W.P.; Ogren, W.E.

    1976-09-01

    The crystallized Hanford high-level wastes stored in single-shell underground tanks consist of sludges and salt cakes covered with supernatural liquor. Purpose of stabilization and isolation is to reduce the releases and losses as a result of a loss of tank integrity. The tanks will be modified so that no inadvertent liquid additions can be made. Criteria for the isolation and stabilization are given and discussed briefly

  16. Coherent Vortices in Strongly Coupled Liquids

    International Nuclear Information System (INIS)

    Ashwin, J.; Ganesh, R.

    2011-01-01

    Strongly coupled liquids are ubiquitous in both nature and laboratory plasma experiments. They are unique in the sense that their average potential energy per particle dominates over the average kinetic energy. Using ''first principles'' molecular dynamics (MD) simulations, we report for the first time the emergence of isolated coherent tripolar vortices from the evolution of axisymmetric flows in a prototype two-dimensional (2D) strongly coupled liquid, namely, the Yukawa liquid. Linear growth rates directly obtained from MD simulations are compared with a generalized hydrodynamic model. Our MD simulations reveal that the tripolar vortices persist over several turn over times and hence may be observed in strongly coupled liquids such as complex plasma, liquid metals and astrophysical systems such as white dwarfs and giant planetary interiors, thereby making the phenomenon universal.

  17. Coherent Vortices in Strongly Coupled Liquids

    Science.gov (United States)

    Ashwin, J.; Ganesh, R.

    2011-04-01

    Strongly coupled liquids are ubiquitous in both nature and laboratory plasma experiments. They are unique in the sense that their average potential energy per particle dominates over the average kinetic energy. Using “first principles” molecular dynamics (MD) simulations, we report for the first time the emergence of isolated coherent tripolar vortices from the evolution of axisymmetric flows in a prototype two-dimensional (2D) strongly coupled liquid, namely, the Yukawa liquid. Linear growth rates directly obtained from MD simulations are compared with a generalized hydrodynamic model. Our MD simulations reveal that the tripolar vortices persist over several turn over times and hence may be observed in strongly coupled liquids such as complex plasma, liquid metals and astrophysical systems such as white dwarfs and giant planetary interiors, thereby making the phenomenon universal.

  18. Dislocation-like Structures in a Simulated Liquid

    DEFF Research Database (Denmark)

    Cotterill, Rodney M J

    1979-01-01

    The free-volume distribution in a simulated Lennard-Jones liquid is heterogeneous. Chains of holes, appearing as segments rather than a continuous network, have lifetimes that are brief compared with the mean vibration period of the atoms. Larger isolated holes persist for longer times. If the ch......The free-volume distribution in a simulated Lennard-Jones liquid is heterogeneous. Chains of holes, appearing as segments rather than a continuous network, have lifetimes that are brief compared with the mean vibration period of the atoms. Larger isolated holes persist for longer times....... If the chains are interpreted as dislocation cores, the observed dislocation density is 1.0×1014 cm-2, but the actual density is probably higher....

  19. Functional interchangeability of late domains, late domain cofactors and ubiquitin in viral budding.

    Directory of Open Access Journals (Sweden)

    Maria Zhadina

    2010-10-01

    Full Text Available The membrane scission event that separates nascent enveloped virions from host cell membranes often requires the ESCRT pathway, which can be engaged through the action of peptide motifs, termed late (L- domains, in viral proteins. Viral PTAP and YPDL-like L-domains bind directly to the ESCRT-I and ALIX components of the ESCRT pathway, while PPxY motifs bind Nedd4-like, HECT-domain containing, ubiquitin ligases (e.g. WWP1. It has been unclear precisely how ubiquitin ligase recruitment ultimately leads to particle release. Here, using a lysine-free viral Gag protein derived from the prototypic foamy virus (PFV, where attachment of ubiquitin to Gag can be controlled, we show that several different HECT domains can replace the WWP1 HECT domain in chimeric ubiquitin ligases and drive budding. Moreover, artificial recruitment of isolated HECT domains to Gag is sufficient to stimulate budding. Conversely, the HECT domain becomes dispensable if the other domains of WWP1 are directly fused to an ESCRT-1 protein. In each case where budding is driven by a HECT domain, its catalytic activity is essential, but Gag ubiquitination is dispensable, suggesting that ubiquitin ligation to trans-acting proteins drives budding. Paradoxically, however, we also demonstrate that direct fusion of a ubiquitin moiety to the C-terminus of PFV Gag can also promote budding, suggesting that ubiquitination of Gag can substitute for ubiquitination of trans-acting proteins. Depletion of Tsg101 and ALIX inhibits budding that is dependent on ubiquitin that is fused to Gag, or ligated to trans-acting proteins through the action of a PPxY motif. These studies underscore the flexibility in the ways that the ESCRT pathway can be engaged, and suggest a model in which the identity of the protein to which ubiquitin is attached is not critical for subsequent recruitment of ubiquitin-binding components of the ESCRT pathway and viral budding to proceed.

  20. Isolation and Purification of Unstable Iridoid Glucosides from Traditional Chinese Medicine by Preparative High Performance Liquid Chromatography Coupled with Solid-phase Extraction

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    An efficient preparative method was successfully developed for isolation and purification of unstable components from medicinal plant extracts, using a combined method of preparative high performance liquid chro-matography(HPLC) and solid-phase extraction(SPE). The aim of this study was to obtain an effective method with high preparative efficiency and importantly to avoid the transformation of unstable compounds. The preparative HPLC system was based on an LC/MS controlled four-channel autopurification system. The SPE method was performed with a C18 packing material to trap the target compounds and to remove the acidic additive derived from the mobile phase. Using this method, the unstable iridoid glucosides(IGs) as model compounds were successfully isolated and purified from the extract of Hedyotis diffusa Willd. Six IGs(including one new minor IG) and one nucleotide compound were simultaneously obtained, each with a purity of 〉91% as determined by HPLC. The structures of the isolated compounds were identified by UPLC/Q-TOF MS, UV, 1D and/or 2D NMR. It was demonstrated that the combination of preparative HPLC with SPE is a versatile tool for preparative purification of unstable compounds from complex natural products.

  1. Rapid isolation of IgNAR variable single-domain antibody fragments from a shark synthetic library.

    Science.gov (United States)

    Shao, Cui-Ying; Secombes, Chris J; Porter, Andrew J

    2007-01-01

    The immunoglobulin isotype IgNAR (Novel Antigen Receptor) was discovered in the serum of the nurse shark (Ginglymostoma cirratum) and wobbegong shark (Orectolobus maculates) as a homodimer of two protein chains, each composed of a single variable domain (V) domain and five constant domains. The IgNAR variable domain contains an intact antigen-binding site and functions as an independent domain able to react to antigen with both high specificity and affinity. Here we describe the successful construction of a synthetic phage-displayed library based upon a single anti-lysozyme clone HEL-5A7 scaffold, which was previously selected from an immune IgNAR variable domain library. The complementarity-determining region 3 (CDR3) loop of this clone was varied in both length and composition and the derived library was used to pan against two model proteins, lysozyme and leptin. A single anti-lysozyme clone (Ly-X20) and anti-leptin clone (Lep-12E1) were selected for further study. Both clones were shown to be functionally expressed in Escherichia coli, extremely thermostable and bind to corresponding antigens specifically. The results here demonstrate that a synthetic IgNAR variable domain library based on a single framework scaffold can be used as a route to generate antigen binders quickly, easily and without the need of immunization.

  2. Improved in situ saccharification of cellulose pretreated by dimethyl sulfoxide/ionic liquid using cellulase from a newly isolated Paenibacillus sp. LLZ1.

    Science.gov (United States)

    Hu, Dongxue; Ju, Xin; Li, Liangzhi; Hu, Cuiying; Yan, Lishi; Wu, Tianyun; Fu, Jiaolong; Qin, Ming

    2016-02-01

    A cellulase producing strain was newly isolated from soil samples and identified as Paenibacillus sp. LLZ1. A novel aqueous-dimethyl sulfoxide (DMSO)/1-ethyl-3-methylimidazolium diethyl phosphate ([Emin]DEP)-cellulase system was designed and optimized. In the pretreatment, DMSO was found to be a low-cost substitute of up to 70% ionic liquid to enhance the cellulose dissolution. In the enzymatic saccharification, the optimum pH and temperature of the Paenibacillus sp. LLZ1 cellulase were identified as 6.0 and 40°C, respectively. Under the optimized reaction condition, the conversion of microcrystalline cellulose and bagasse cellulose increased by 39.3% and 37.6%, compared with unpretreated cellulose. Compared to current methods of saccharification, this new approach has several advantages including lower operating temperature, milder pH, and less usage of ionic liquid, indicating a marked progress in environmental friendly hydrolysis of biomass-based materials. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. FY1995 ultrafast photonic devices using dielectric domain superlattice; 1995 nendo yudentai domain chokoshi wo mochiita chokosoku photonic device

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-31

    All optical wavelength conversion around 1550nm is of great importance for the wavelength division multiplexing optical communication system. A dielectric domain superlattice, which has a periodically domain inverted structure, has a wide potential for the various nonlinear interactions such as second harmonic generation (SHG) and difference frequency generation (DFG). The purpose of our research is to establish the theoretical bases and fabrication processes of the guided-wave wavelength converter based on the DFG by domain-inverted LiTaO{sub 3}. We have investigated basic characteristics of guided-wave DFG devices and developed the domain-inversion process by an electric field poling utilizing a liquid electrolyte consisting of LiCI in deionized water as a electrode for applying the electric field to LiTaO{sub 3} substrate. By controlling the injection current for the domain inversion precisely, we fabricated successfully uniform domain-inverted structures. 0.5mm-thick domain-inverted LiTaO{sub 3} of 7.8, 17.2 and 21.3 {mu}m periods and 0.5 duty ratio were obtained by optimizing electrode structure and the domain-inversion process. Waveguide structures can increase the conversion efficiency of DFG by several orders of magnitude over bulk interactions. We have also developed waveguide fabrication process for the domain-inverted LiTaO{sub 3} substrate. Low loss proton-exchanged waveguides were formed by annealed proton exchange technique without a degradation of the domain inversion structure. Domain-controlled nonlinear optics by designing the ferroelectric domain structure of LiTaO{sub 3} and LiNbO{sub 3} make it possible to extend all the spectral range from ultra-violet to far-infrared and THz wave region. (NEDO)

  4. Isolation and Characterization of Blue Green Algae from Egyptian ...

    African Journals Online (AJOL)

    meldemellawy

    2014-02-20

    Feb 20, 2014 ... aminotransferase (AMT) domains of the mycE and ndaF genes (Jungblut et al., 2006) allowing detection of microcystin and nodularin-producing cyanobacteria. MATERIALS AND METHODS. Isolation and cultivation of blue green algae. Blue green algae had been isolated from soil of Rice field in river.

  5. Ohcratoxin producing Aspergillus spp. Isolated from tropical soils in Sarawak, Malaysia

    Directory of Open Access Journals (Sweden)

    J.S.S. Seelan

    2010-03-01

    Full Text Available Aspergillus strains isolated from tropical soils were selected for additional characterization and for ochratoxin analysis, which was determined by ELISA method and high performance liquid chromatography (HPLC profiles. Because of its great morphological variability and mycotoxin production availability, 18 isolates of Aspergillus species were selected for this study. Only two isolates of these tropical soils, A. sulphureus and A. carbonarius, showed positive results for ohcratoxin (OA in lower concentration (0.05-0.10 µg/ml. Ochratoxin production by these species was confirmed by high performance liquid chromatography. HPLC analysis for ochratoxin producing A. sulphureus and A. carbonarius showed retention time, Rt value = 4.417 and Rt value = 4.081 respectively.

  6. Mechanism of constitution liquid film migration

    Energy Technology Data Exchange (ETDEWEB)

    Zuo, Hongjun [Univ. of Alabama, Birmingham, AL (United States)

    1999-06-01

    Liquid film migration (LFM) in liquid phase sintering classically involves a large metastable liquid volume adjacent to solid, and migration occurs at an isolated solid-liquid (S-L) interface. Constitutional liquid film migration (CLFM), discovered in alloy 718, has major characteristics similar to those of LFM, except that the metastable liquid is from the constitutional liquation of precipitates on the grain boundary. The similarity between LFM and CLFM has led to the theory that coherency lattice strain responsible for LFM is also responsible for CLFM. The coherency strain hypothesis was tested in this study by evaluating whether the Hillert model of LFM would also apply for CLFM. Experimental results of CLFM in alloy 718 showed that migration velocity followed the trend predicted by the Hillert model. This indicates that the coherency strain hypothesis of LFM also applies for CLFM and that the coherency lattice strain responsible for LFM is also the driving force for CLFM.

  7. Leveraging liquid dielectrophoresis for microfluidic applications

    International Nuclear Information System (INIS)

    Chugh, Dipankar; Kaler, Karan V I S

    2008-01-01

    Miniaturized fluidic systems have been developed in recent years and offer new and novel means of leveraging the domain of microfluidics for the development of micro-total analysis systems (μTAS). Initially, such systems employed closed microchannels in order to facilitate chip-based biochemical assays, requiring very small quantities of sample and/or reagents and furthermore providing rapid and low-cost analysis on a compact footprint. More recently, advancements in the domain of surface microfluidics have suggested that similar low volume sample handling and manipulation capabilities for bioassays can be attained by leveraging the phenomena of liquid dielectrophoresis and droplet dielectrophoresis (DEP), without the need for separate pumps or valves. Some of the key aspects of this surface microfluidic technology and its capabilities are discussed and highlighted in this paper. We, furthermore, examine the integration and utility of liquid DEP and droplet DEP in providing rapid and automated sample handling and manipulation capabilities on a compact chip-based platform

  8. Isolation and characterization of two malathiondegrading ...

    African Journals Online (AJOL)

    Pseudomonas aeruginosa and Pseudomonas mendocina degrading malathion were studied. Morphological, biochemical and 16S rRNA genes for bacterial identification were selected. Biodegradation of some organophosphorus compounds with the 2 bacterial isolates was determined by high performance liquid ...

  9. Co-evolution of affinity and stability of grafted amyloid-motif domain antibodies.

    Science.gov (United States)

    Julian, Mark C; Lee, Christine C; Tiller, Kathryn E; Rabia, Lilia A; Day, Evan K; Schick, Arthur J; Tessier, Peter M

    2015-10-01

    An attractive approach for designing lead antibody candidates is to mimic natural protein interactions by grafting peptide recognition motifs into the complementarity-determining regions (CDRs). We are using this approach to generate single-domain (VH) antibodies specific for amyloid-forming proteins such as the Alzheimer's Aβ peptide. Here, we use random mutagenesis and yeast surface display to improve the binding affinity of a lead VH domain grafted with Aβ residues 33-42 in CDR3. Interestingly, co-selection for improved Aβ binding and VH display on the surface of yeast yields antibody domains with improved affinity and reduced stability. The highest affinity VH domains were strongly destabilized on the surface of yeast as well as unfolded when isolated as autonomous domains. In contrast, stable VH domains with improved affinity were reliably identified using yeast surface display by replacing the display antibody that recognizes a linear epitope tag at the terminus of both folded and unfolded VH domains with a conformational ligand (Protein A) that recognizes a discontinuous epitope on the framework of folded VH domains. Importantly, we find that selection for improved stability using Protein A without simultaneous co-selection for improved Aβ binding leads to strong enrichment for stabilizing mutations that reduce antigen binding. Our findings highlight the importance of simultaneously optimizing affinity and stability to improve the rapid isolation of well-folded and specific antibody fragments. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  10. Stiffening solids with liquid inclusions

    Science.gov (United States)

    Style, Robert W.; Boltyanskiy, Rostislav; Allen, Benjamin; Jensen, Katharine E.; Foote, Henry P.; Wettlaufer, John S.; Dufresne, Eric R.

    2015-01-01

    From bone and wood to concrete and carbon fibre, composites are ubiquitous natural and synthetic materials. Eshelby’s inclusion theory describes how macroscopic stress fields couple to isolated microscopic inclusions, allowing prediction of a composite’s bulk mechanical properties from a knowledge of its microstructure. It has been extended to describe a wide variety of phenomena from solid fracture to cell adhesion. Here, we show experimentally and theoretically that Eshelby’s theory breaks down for small liquid inclusions in a soft solid. In this limit, an isolated droplet’s deformation is strongly size-dependent, with the smallest droplets mimicking the behaviour of solid inclusions. Furthermore, in opposition to the predictions of conventional composite theory, we find that finite concentrations of small liquid inclusions enhance the stiffness of soft solids. A straightforward extension of Eshelby’s theory, accounting for the surface tension of the solid-liquid interface, explains our experimental observations. The counterintuitive stiffening of solids by fluid inclusions is expected whenever inclusion radii are smaller than an elastocapillary length, given by the ratio of the surface tension to Young’s modulus of the solid matrix. These results suggest that surface tension can be a simple and effective mechanism to cloak the far-field elastic signature of inclusions.

  11. Seismic isolation design guidelines for KALIMER(Revision A)

    International Nuclear Information System (INIS)

    Yoo, B; Koo, Gyeong Hoi; Lee, J. H.

    2000-04-01

    The main purpose of this report is to develop the seismic isolation design guideline for KALIMER(Korea Advanced LIquid MEtal Reactor). The proposed design rules(revision A) are only applicable to the seismic isolation design with using the high damping laminated rubber bearings. When using other seismic isolation devices and applying to 3-dimensional isolation, the proposed guidelines shall be modified and added with proper research data. The rules described in this report are based on the research results performed up to now but needed to be upgraded and verified with more detail research works for the future

  12. Carbon nanotubes: are they dispersed or dissolved in liquids?

    Directory of Open Access Journals (Sweden)

    Premkumar Thathan

    2011-01-01

    Full Text Available Abstract Carbon nanotubes (CNTs constitute a novel class of nanomaterials with remarkable applications in diverse domains. However, the main intrincsic problem of CNTs is their insolubility or very poor solubility in most of the common solvents. The basic key question here is: are carbon nanotubes dissolved or dispersed in liquids, specifically in water? When analyzing the scientific research articles published in various leading journals, we found that many researchers confused between "dispersion" and "solubilization" and use the terms interchangeably, particularly when stating the interaction of CNTs with liquids. In this article, we address this fundamental issue to give basic insight specifically to the researchers who are working with CNTs as well asgenerally to scientists who deal with nano-related research domains.

  13. Design and Testing of a Thermostable Platform for Multimerization of Single Domain Antibodies

    Science.gov (United States)

    2012-08-01

    H.J. Properties , production, and applications of camelid single domain antibody fragments. Appl. Microbiol. Biot. 2007, 77, 13‒22. 2. Goldman...Conway, J.; Sherwood, L.J.; Fech, M.; Vo, B.; Liu, J.L.; Hayhurst, A. Thermostable llama single domain antibodies for detection of Botulinum A...antiparallel coiled-coil inserted. J. Mol. Bio. 2001, 306, 25‒35. 9. Liu, J.L.; Anderson, G.P.; Goldman, E.R. Isolation of anti- toxin single domain

  14. Different methods of membrane domains isolation result in similar 2-D distribution patterns of membrane domain proteins

    Czech Academy of Sciences Publication Activity Database

    Matoušek, Petr; Hodný, Zdeněk; Švandová, I.; Svoboda, Petr

    2003-01-01

    Roč. 81, č. 6 (2003), s. 365-372 ISSN 0829-8211 R&D Projects: GA MŠk LN00A026 Grant - others:Wellcome Trust(GB) xx Institutional research plan: CEZ:AV0Z5011922; CEZ:MSM 113100003; CEZ:AV0Z5039906 Keywords : membrane domain * G protein * two-dimensional electrophoresis * GPI-ancored proteins Subject RIV: CE - Biochemistry Impact factor: 2.456, year: 2003

  15. Microbial accumulation of uranium from nuclear liquid waste

    International Nuclear Information System (INIS)

    Mahmood, A.H.

    1986-01-01

    This investigation includes the isolation, identification and the fluctuations of the population densities of microorganisms in the nuclear liquid waste released by some laboratories of Iraqi Atomic Energy Commission. The efficiency of uranium accumulation on isolates (22 bacterial strains, 24 fungal strains and 6 yeast strains) was assessed in aqueous solution using fluorometric techniques. Two of the isolated microoganisms namely Bacillus sp. -15B and Mucor sp.16F showed exceptionally high attitude towards uranium accumulation. Optimal conditions required for efficient accumulation and recovery of uranium was then studied using the two selected isolates. 10 figs.; 162 refs.; 16 tabs

  16. Diffusion mediated coagulation and fragmentation based study of domain formation in lipid bilayer membrane

    Energy Technology Data Exchange (ETDEWEB)

    Rao, Laxminarsimha V., E-mail: laxman@iitk.ac.in [Mechanics and Applied Mathematics Group, Department of Mechanical Engineering, Indian Institute of Technology Kanpur, Kanpur 208016 (India); Roy, Subhradeep [Department of Biomedical Engineering and Mechanics (MC 0219), Virginia Tech, 495 Old Turner Street, Blacksburg, VA 24061 (United States); Das, Sovan Lal [Mechanics and Applied Mathematics Group, Department of Mechanical Engineering, Indian Institute of Technology Kanpur, Kanpur 208016 (India)

    2017-01-15

    We estimate the equilibrium size distribution of cholesterol rich micro-domains on a lipid bilayer by solving Smoluchowski equation for coagulation and fragmentation. Towards this aim, we first derive the coagulation kernels based on the diffusion behaviour of domains moving in a two dimensional membrane sheet, as this represents the reality better. We incorporate three different diffusion scenarios of domain diffusion into our coagulation kernel. Subsequently, we investigate the influence of the parameters in our model on the coagulation and fragmentation behaviour. The observed behaviours of the coagulation and fragmentation kernels are also manifested in the equilibrium domain size distribution and its first moment. Finally, considering the liquid domains diffusing in a supported lipid bilayer, we fit the equilibrium domain size distribution to a benchmark solution.

  17. Globular, Sponge-like to Layer-like Morphological Transition in 1-n-Alkyl-3-methylimidazolium Octylsulfate Ionic Liquid Homologous Series.

    Science.gov (United States)

    Kapoor, Utkarsh; Shah, Jindal K

    2018-01-11

    Segregation of polar and nonpolar domains in ionic liquids for which either the cation or anion is responsible for inducing nonpolar domains is well understood. On the other hand, information regarding the nanoscale heterogeneities originating due to the presence of nonpolar content on both the ions is rudimentary at this point. The present contribution is aimed at addressing this question and focuses on a molecular dynamics simulation study to probe nanoscale structural and aggregation features of the 1-n-alkyl-3-methylimidazolium [C n mim] octylsulfate [C 8 SO 4 ] ionic liquid homologous series (n = 2, 4, 6, 8, 10, and 12). The objective of this work is to determine the effect of increasing alkyl chain length in the cation on nonpolar domain formation, especially when the alkyl chain lengths from both the ions participate in defining such domains. The results indicate that all the ionic liquids form nonpolar domains, morphology of which gradually changes from globular, sponge-like to layer-like structure with increase in the cationic alkyl chain length. The length of the nonpolar domains calculated from the total structure factor for [C 10 mim][C 8 SO 4 ] is considerably higher than that reported for other imidazolium-based ionic liquid containing smaller anions. The structure factor for [C 12 mim][C 8 SO 4 ] ionic liquid contains multiple intermediate peaks separating the charge alternation peak and pre-peak, which points to nonpolar domains of varying lengths, an observation that remains to be validated. Analysis of the heterogeneous order parameters and orientational correlation functions of the alkyl chains further suggests an increase in the spatial heterogeneity and long-range order along the homologous series. The origin of rich diversity of structures obtained by introducing nonpolar content on both the ions is discussed.

  18. Proteins containing the UBA domain are able to bind to multi-ubiquitin chains

    DEFF Research Database (Denmark)

    Wilkinson, C R; Seeger, M; Hartmann-Petersen, R

    2001-01-01

    The UBA domain is a motif found in a variety of proteins, some of which are associated with the ubiquitin-proteasome system. We describe the isolation of a fission-yeast gene, mud1+, which encodes a UBA domain containing protein that is able to bind multi-ubiquitin chains. We show that the UBA do...

  19. Liquidity supply and money velocity co-movements in the Eurozone – Time-Frequency Domain Approach

    Directory of Open Access Journals (Sweden)

    Svatopluk Kapounek

    2012-01-01

    Full Text Available The authors focus on financial stability in the Eurozone and propose alternative indicator for macro-prudential policy implementation. Rapid growth of the shadow banking system biases increase in loans to identify financial instability. The velocity of money represented money demand in the economy. The empirical part of the paper applies wavelet analysis to identify cyclical co-movements in money velocity and liquidity supply. The authors provide recommendations for policymakers to stabilize global liquidity shocks and reduce procyclical effects by institutions which supply official liquidity in their domestic currency – central banks.

  20. Properties of catalase-peroxidase lacking its C-terminal domain

    International Nuclear Information System (INIS)

    Baker, Ruletha D.; Cook, Carma O.; Goodwin, Douglas C.

    2004-01-01

    Catalase-peroxidases have a two-domain structure. The N-terminal domain contains the bifunctional active site, but the function of the C-terminal domain is unknown. We produced catalase-peroxidase containing only its N-terminal domain (KatG Nterm ). Removal of the C-terminal domain did not result in unexpected changes in secondary structure as evaluated by CD, but KatG Nterm had neither catalase nor peroxidase activity. Partial recovery of both activities was achieved by incubating KatG Nterm with the separately expressed and isolated KatG C-terminal domain. Spectroscopic measurements revealed a shift in heme environment from a mixture of high-spin species (wtKatG) to exclusively hexacoordinate, low-spin (KatG Nterm ). Moreover, a >1000-fold lower k on for CN - binding was observed for KatG Nterm . EPR spectra for KatG Nterm and the results of site-specific substitution of active site histidines suggested that the distal histidine was the sixth ligand. Thus, one important role for the C-terminal domain may be to support the architecture of the active site, preventing heme ligation by this catalytically essential residue

  1. Comparison of pathogenic domains of rabies and African rabies-related lyssaviruses and pathogenicity observed in mice

    Directory of Open Access Journals (Sweden)

    Joe Kgaladi

    2013-03-01

    Full Text Available Several lyssavirus species occur in Africa (Rabies virus, Lagos bat virus, Mokola virus, Duvenhage virus, Shimoni bat virus and Ikoma lyssavirus, displaying a high sequence diversity between isolates belonging to the same species. There is limited information about comparative pathogenesis of these African lyssaviruses and this precludes authoritative opinion on the potential public and veterinary health impact. In this study, an analysis of representative African lyssaviruses attempted to correlate viral genomic sequence similarities and differences with the corresponding pathogenic profiles observed in mice. The study demonstrated that the virus isolates evaluated could be lethal to mice when introduced intramuscularly and that different isolates of the same lyssavirus species differ in their virulence. Using real-time polymerase chain reaction (PCR, viral RNA was detected in brain tissue, but no viral RNA was detected in the salivary glands or blood of mice that succumbed to infection. Comparison of known pathogenic domains indicated that pathogenicity is likely to be dependent on multiple domains. Cumulatively, our results re-emphasised the realisation that the pathogenicity of a lyssavirus species cannot be deduced based on studies of only a single isolate of the species or a single pathogenic domain.

  2. Sorption isolation of strontium from seawater

    International Nuclear Information System (INIS)

    Avramenko, V.A.; Zheleznov, V.V.; Kaplun, E.V.; Sokol'nitskaya, T.A.; Yukhkam, A.A.

    2001-01-01

    Sorption isolation of strontium from seawater is considered and prospects of use of selective adsorbents for purification of seawater or liquid radioactive wastes mixed with seawater from 90 Sr are discussed. Comparative analysis of sorptive properties of adsorbents of different nature is done. It is shown that sorption-reagent materials developed by authors can to afford effective separation of 90 Sr from seawater. Possible mechanism of strontium sorption by these adsorbents is considered. The prospect of their use for purification of liquid radioactive wastes from strontium is shown [ru

  3. Topological sound in active-liquid metamaterials

    Science.gov (United States)

    Souslov, Anton; van Zuiden, Benjamin C.; Bartolo, Denis; Vitelli, Vincenzo

    2017-11-01

    Liquids composed of self-propelled particles have been experimentally realized using molecular, colloidal or macroscopic constituents. These active liquids can flow spontaneously even in the absence of an external drive. Unlike spontaneous active flow, the propagation of density waves in confined active liquids is not well explored. Here, we exploit a mapping between density waves on top of a chiral flow and electrons in a synthetic gauge field to lay out design principles for artificial structures termed topological active metamaterials. We design metamaterials that break time-reversal symmetry using lattices composed of annular channels filled with a spontaneously flowing active liquid. Such active metamaterials support topologically protected sound modes that propagate unidirectionally, without backscattering, along either sample edges or domain walls and despite overdamped particle dynamics. Our work illustrates how parity-symmetry breaking in metamaterial structure combined with microscopic irreversibility of active matter leads to novel functionalities that cannot be achieved using only passive materials.

  4. Time-domain multiple-quantum NMR

    International Nuclear Information System (INIS)

    Weitekamp, D.P.

    1982-11-01

    The development of time-domain multiple-quantum nuclear magnetic resonance is reviewed through mid 1982 and some prospects for future development are indicated. Particular attention is given to the problem of obtaining resolved, interpretable, many-quantum spectra for anisotropic magnetically isolated systems of coupled spins. New results are presented on a number of topics including the optimization of multiple-quantum-line intensities, analysis of noise in two-dimensional spectroscopy, and the use of order-selective excitation for cross polarization between nuclear-spin species

  5. A Tiered Control Plane Model for Service Function Chaining Isolation

    Directory of Open Access Journals (Sweden)

    Håkon Gunleifsen

    2018-06-01

    Full Text Available This article presents an architecture for encryption automation in interconnected Network Function Virtualization (NFV domains. Current NFV implementations are designed for deployment within trusted domains, where overlay networks with static trusted links are utilized for enabling network security. Nevertheless, within a Service Function Chain (SFC, Virtual Network Function (VNF flows cannot be isolated and end-to-end encrypted because each VNF requires direct access to the overall SFC data-flow. This restricts both end-users and Service Providers from enabling end-to-end security, and in extended VNF isolation within the SFC data traffic. Encrypting data flows on a per-flow basis results in an extensive amount of secure tunnels, which cannot scale efficiently in manual configurations. Additionally, creating secure data plane tunnels between NFV providers requires secure exchange of key parameters, and the establishment of an east–west control plane protocol. In this article, we present an architecture focusing on these two problems, investigating how overlay networks can be created, isolated, and secured dynamically. Accordingly, we propose an architecture for automated establishment of encrypted tunnels in NFV, which introduces a novel, tiered east–west communication channel between network controllers in a multi-domain environment.

  6. Structural Characterization of Monomeric/Dimeric State of p59fyn SH2 Domain.

    Science.gov (United States)

    Huculeci, Radu; Kieken, Fabien; Garcia-Pino, Abel; Buts, Lieven; van Nuland, Nico; Lenaerts, Tom

    2017-01-01

    Src homology 2 (SH2) domains are key modulators in various signaling pathways allowing the recognition of phosphotyrosine sites of different proteins. Despite the fact that SH2 domains acquire their biological functions in a monomeric state, a multitude of reports have shown their tendency to dimerize. Here, we provide a technical description on how to isolate and characterize by gel filtration, circular dichroism (CD), and nuclear magnetic resonance (NMR) each conformational state of p59 fyn SH2 domain.

  7. The liquidation of liquid radioactive waste on nuclear medicine departments

    International Nuclear Information System (INIS)

    Fueriova, A.

    1995-01-01

    The most serious problems for Clinic of Nuclear Medicine of National Oncological Institute, Bratislava (CNM) is the localization of CNM in the downtown, inside the hospital area with the dilution water deficit. This department is the only one in Slovak Republic performing therapeutical applications. To be able to perform the necessary amount of therapies and also to introduce a new therapeutical methods, in 1992-1994 the old liquidation waste disposal station (LWDS) was reconstructed with the aim to satisfy the newest requirements of radiation hygiene. LWDS is the 5-floor object partly underground which satisfied the requirements for liquidation of radioactive liquid waste from diagnostic procedures(annually 5000 patients) and also from 200 therapeutical applications annually (15 beds, 720 GBq iodine-131). The capacity of LWDS is able to store about 90 m 3 liquid radioactive waste. Part of the underground spaces are used for the storage of solid radioactive trash. The liquid waste from CNM is collected through isolated metal sewage system to the storage with continuous observation of water specific activity. According to the activity, the liquid waste is placed to the 5 decay storages with the volume about 15 m 3 . The six one serves for the case of technical accident. When the activity declines, the liquid waste is diluted with non active medical trash to the level which is acceptable by low about radiation hygiene protection. The storage walls are made from barium-concrete 25-50 cm thick which is enough for sufficient protection of operation staff and also for walking around persons. Double-layer high quality chemical material prevents the water leak and diffusion of radionuclides into the concrete. Technology consists of cast-iron drains, powerful slush pumps, operation valves, regulation technology from dosimetric system for continuous monitoring of specific activity, for managing system with powerful industrial computer

  8. The liquidation of liquid radioactive waste on nuclear medicine departments

    Energy Technology Data Exchange (ETDEWEB)

    Fueriova, A [National Oncological Institue, Bratislava (Slovakia). Hospital St. Elis, Clinic of Nuclear Medicine

    1996-12-31

    The most serious problems for Clinic of Nuclear Medicine of National Oncological Institute, Bratislava (CNM) is the localization of CNM in the downtown, inside the hospital area with the dilution water deficit. This department is the only one in Slovak Republic performing therapeutical applications. To be able to perform the necessary amount of therapies and also to introduce a new therapeutical methods, in 1992-1994 the old liquidation waste disposal station (LWDS) was reconstructed with the aim to satisfy the newest requirements of radiation hygiene. LWDS is the 5-floor object partly underground which satisfied the requirements for liquidation of radioactive liquid waste from diagnostic procedures(annually 5000 patients) and also from 200 therapeutical applications annually (15 beds, 720 GBq iodine-131). The capacity of LWDS is able to store about 90 m{sup 3} liquid radioactive waste. Part of the underground spaces are used for the storage of solid radioactive trash. The liquid waste from CNM is collected through isolated metal sewage system to the storage with continuous observation of water specific activity. According to the activity, the liquid waste is placed to the 5 decay storages with the volume about 15 m{sup 3}. The six one serves for the case of technical accident. When the activity declines, the liquid waste is diluted with non active medical trash to the level which is acceptable by low about radiation hygiene protection. The storage walls are made from barium-concrete 25-50 cm thick which is enough for sufficient protection of operation staff and also for walking around persons. Double-layer high quality chemical material prevents the water leak and diffusion of radionuclides into the concrete. Technology consists of cast-iron drains, powerful slush pumps, operation valves, regulation technology from dosimetric system for continuous monitoring of specific activity, for managing system with powerful industrial computer.

  9. Domain growth kinetics in stratifying foam films

    Science.gov (United States)

    Zhang, Yiran; Sharma, Vivek

    2015-11-01

    Baking bread, brewing cappuccino, pouring beer, washing dishes, shaving, shampooing, whipping eggs and blowing bubbles all involve creation of aqueous foam films. Typical foam films consist of two surfactant-laden surfaces that are ~ 5 nm - 10 micron apart. Sandwiched between these interfacial layers is a fluid that drains primarily under the influence of viscous and interfacial forces, including disjoining pressure. Interestingly, a layered ordering of micelles inside the foam films (thickness characteristic scaling laws. Though several studies have focused on the expansion dynamics of isolated domains that exhibit a diffusion-like scaling, the change in expansion kinetics observed after domains contact with the Plateau border has not been reported and analyzed before.

  10. Interaction between the PH and START domains of ceramide transfer protein competes with phosphatidylinositol 4-phosphate binding by the PH domain.

    Science.gov (United States)

    Prashek, Jennifer; Bouyain, Samuel; Fu, Mingui; Li, Yong; Berkes, Dusan; Yao, Xiaolan

    2017-08-25

    De novo synthesis of the sphingolipid sphingomyelin requires non-vesicular transport of ceramide from the endoplasmic reticulum to the Golgi by the multidomain protein ceramide transfer protein (CERT). CERT's N-terminal pleckstrin homology (PH) domain targets it to the Golgi by binding to phosphatidylinositol 4-phosphate (PtdIns(4)P) in the Golgi membrane, whereas its C-terminal StAR-related lipid transfer domain (START) carries out ceramide transfer. Hyperphosphorylation of a serine-rich motif immediately after the PH domain decreases both PtdIns(4)P binding and ceramide transfer by CERT. This down-regulation requires both the PH and START domains, suggesting a possible inhibitory interaction between the two domains. In this study we show that isolated PH and START domains interact with each other. The crystal structure of a PH-START complex revealed that the START domain binds to the PH domain at the same site for PtdIns(4)P-binding, suggesting that the START domain competes with PtdIns(4)P for association with the PH domain. We further report that mutations disrupting the PH-START interaction increase both PtdIns(4)P-binding affinity and ceramide transfer activity of a CERT-serine-rich phosphorylation mimic. We also found that these mutations increase the Golgi localization of CERT inside the cell, consistent with enhanced PtdIns(4)P binding of the mutant. Collectively, our structural, biochemical, and cellular investigations provide important structural insight into the regulation of CERT function and localization. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  11. Domain configurations in dislocations embedded hexagonal manganite systems: From the view of graph theory

    Science.gov (United States)

    Cheng, Shaobo; Zhang, Dong; Deng, Shiqing; Li, Xing; Li, Jun; Tan, Guotai; Zhu, Yimei; Zhu, Jing

    2018-04-01

    Topological defects and their interactions often arouse multiple types of emerging phenomena from edge states in Skyrmions to disclination pairs in liquid crystals. In hexagonal manganites, partial edge dislocations, a prototype topological defect, are ubiquitous and they significantly alter the topologically protected domains and their behaviors. Herein, combining electron microscopy experiment and graph theory analysis, we report a systematic study of the connections and configurations of domains in this dislocation embedded system. Rules for domain arrangement are established. The dividing line between domains, which can be attributed by the strain field of dislocations, is accurately described by a genus model from a higher dimension in the graph theory. Our results open a door for the understanding of domain patterns in topologically protected multiferroic systems.

  12. Study of open systems with molecules in isotropic liquids

    Science.gov (United States)

    Kondo, Yasushi; Matsuzaki, Masayuki

    2018-05-01

    We are interested in dynamics of a system in an environment, or an open system. Such phenomena as crossover from Markovian to non-Markovian relaxation and thermal equilibration are of our interest. Open systems have experimentally been studied with ultra cold atoms, ions in traps, optics, and cold electric circuits because well-isolated systems can be prepared here and thus the effects of environments can be controlled. We point out that some molecules solved in isotropic liquid are well isolated and thus they can also be employed for studying open systems in Nuclear Magnetic Resonance (NMR) experiments. First, we provide a short review on related phenomena of open systems that helps readers to understand our motivation. We, then, present two experiments as examples of our approach with molecules in isotropic liquids. Crossover from Markovian to non-Markovian relaxation was realized in one NMR experiment, while relaxation-like phenomena were observed in approximately isolated systems in the other.

  13. Local mobility in lipid domains of supported bilayers characterized by atomic force microscopy and fluorescence correlation spectroscopy.

    Energy Technology Data Exchange (ETDEWEB)

    Frankel, Daniel J.; Buranda, T. (University of New Mexico, Albuquerque, NM); Burns, Alan Richard

    2005-01-01

    Fluorescence correlation spectroscopy (FCS) is used to examine mobility of labeled probes at specific sites in supported bilayers consisting of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) lipid domains in 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC). Those sites are mapped beforehand with simultaneous atomic force microscopy and submicron confocal fluorescence imaging, allowing characterization of probe partitioning between gel DPPC and disordered liquid DOPC domains with corresponding topography of domain structure. We thus examine the relative partitioning and mobility in gel and disordered liquid phases for headgroup- and tailgroup-labeled GM1 ganglioside probes and for headgroup- and tailgroup-labeled phospholipid probes. For the GM1 probes, large differences in mobility between fluid and gel domains are observed; whereas unexpected mobility is observed in submicron gel domains for the phospholipid probes. We attribute the latter to domain heterogeneities that could be induced by the probe. Furthermore, fits to the FCS data for the phospholipid probes in the DOPC fluid phase require two components (fast and slow). Although proximity to the glass substrate may be a factor, local distortion of the probe by the fluorophore could also be important. Overall, we observe nonideal aspects of phospholipid probe mobility and partitioning that may not be restricted to supported bilayers.

  14. Isolation of Acremonium species producing cephalosporine C (CPC ...

    African Journals Online (AJOL)

    SERVER

    2007-11-19

    Nov 19, 2007 ... selective media and Acremonium sp. were isolated. The presence of CPC antibiotic in the fermentation broths of these species was ... Penicillium sp. 28%. Alternaria sp. .... On-line high performance liquid chromatography for ...

  15. Dynamic thermal expansivity of liquids near the glass transition.

    Science.gov (United States)

    Niss, Kristine; Gundermann, Ditte; Christensen, Tage; Dyre, Jeppe C

    2012-04-01

    Based on previous works on polymers by Bauer et al. [Phys. Rev. E 61, 1755 (2000)], this paper describes a capacitative method for measuring the dynamical expansion coefficient of a viscous liquid. Data are presented for the glass-forming liquid tetramethyl tetraphenyl trisiloxane (DC704) in the ultraviscous regime. Compared to the method of Bauer et al., the dynamical range has been extended by making time-domain experiments and by making very small and fast temperature steps. The modeling of the experiment presented in this paper includes the situation in which the capacitor is not full because the liquid contracts when cooling from room temperature down to around the glass-transition temperature, which is relevant when measuring on a molecular liquid rather than a polymer.

  16. Efficient operation of the liquid nitrogen supply station for the cryogenic equipment of the pilot plant for tritium and deuterium separation

    International Nuclear Information System (INIS)

    Gherghinescu, Sorin; Popescu, Gheorghe

    2009-01-01

    Full text: At liquid nitrogen temperature the materials lose their elastic properties and become brittle. Protecting the personnel working with liquid nitrogen becomes difficult and to avoid accidents special equipment is used as helmets, gloves, goggles, special footwear, etc. The liquid nitrogen can destroy insulation of electrical cables, and so short circuits and electrocution can occur. Objects made of carbon steel (like pipes, props, containers, pillars, metal roofs, etc) when cooled by a sufficient amount of cryogenic liquid can break down to minimal mechanical stresses. Exceedingly dangerous is liquid nitrogen entered and retained into carbon steel ducts carrying pressured gas (even et low pressure values), since their cooling at extremely low temperatures can provoke their explosion. Resulting pieces and fragments are dangerous for both personnel and equipment around. The gas components of atmosphere (oxygen, nitrogen, argon) have critical parameters which allow liquefaction only at high pressure. For this reason they are called 'permanent gases'. Consequently, transformed in cryogenic liquids in closed precincts these gases will get totally vaporised when the precincts are not properly thermally isolated. The resulting raised pressure can lead to precinct destruction. For instance such event happens when an amount of liquid nitrogen is isolated into an external pipe between two closed taps while a relief valve is not in place. In such conditions isolation of liquid nitrogen ducts is absolutely necessary. This report reviews various solutions for obtaining an efficient isolation. All thermal isolations aim at reducing the heat transfer. In cryogenics the heat transfer from environment to the fluid in liquid phase is an important factor affecting the efficiency and yield of the liquefaction system. Choosing the type of isolation depends essentially on the specific application. The factors which must be considered are the cooling power, weight, the

  17. Domain size polydispersity effects on the structural and dynamical properties in lipid monolayers with phase coexistence

    Science.gov (United States)

    Rufeil-Fiori, Elena; Banchio, Adolfo J.

    Lipid monolayers with phase coexistence are a frequently used model for lipid membranes. In these systems, domains of the liquid-condensed phase always present size polydispersity. However, very few theoretical works consider size distribution effects on the monolayer properties. Because of the difference in surface densities, domains have excess dipolar density with respect to the surrounding liquid expanded phase, originating a dipolar inter-domain interaction. This interaction depends on the domain area, and hence the presence of a domain size distribution is associated with interaction polydispersity. Inter-domain interactions are fundamental to understanding the structure and dynamics of the monolayer. For this reason, it is expected that polydispersity significantly alters monolayer properties. By means of Brownian dynamics simulations, we study the radial distribution function (RDF), the average mean square displacement and the average time-dependent self-diffusion coefficient, D(t), of lipid monolayers with normal distributed size domains. It was found that polydispersity strongly affects the value of the interaction strength obtained, which is greatly underestimated if polydispersity is not considered. However, within a certain range of parameters, the RDF obtained from a polydisperse model can be well approximated by that of a monodisperse model, suitably fitting the interaction strength, even for 40% polydispersities. For small interaction strengths or small polydispersities, the polydisperse systems obtained from fitting the experimental RDF have an average mean square displacement and D(t) in good agreement with that of the monodisperse system.

  18. Prion-like domains in RNA binding proteins are essential for building subnuclear paraspeckles

    NARCIS (Netherlands)

    Hennig, Sven; Kong, Geraldine; Mannen, Taro; Sadowska, Agata; Kobelke, Simon; Blythe, Amanda; Knott, Gavin J; Iyer, K Swaminathan; Ho, Diwei; Newcombe, Estella A; Hosoki, Kana; Goshima, Naoki; Kawaguchi, Tetsuya; Hatters, Danny; Trinkle-Mulcahy, Laura; Hirose, Tetsuro; Bond, Charles S; Fox, Archa H

    2015-01-01

    Prion-like domains (PLDs) are low complexity sequences found in RNA binding proteins associated with the neurodegenerative disorder amyotrophic lateral sclerosis. Recently, PLDs have been implicated in mediating gene regulation via liquid-phase transitions that drive ribonucleoprotein granule

  19. A terahertz transmission imaging based approach for liquid alcohol wettability investigation

    Science.gov (United States)

    Huang, Hui; Zhao, Hongwei; Zhang, Bo; Su, Yunyun; Jiang, Weixiang; Cai, Bin; You, Guanjun; Ma, Yan

    2018-03-01

    By using terahertz time-domain spectroscopy (THz-TDS), the transmission spectral images of a series of aliphatic monohydric liquid alcohols were investigated in this work. The image gray value indicated the non-uniform distribution of the liquid. After noise reduction, the depth distribution was computed from the image content, which depended on the wettability of the container surface by the liquid. Then the volume of the liquid crept up to the container surface was compared quantitatively. Our result showed that the surface wettability of the PS container surface by the liquids increased with the alcohol alkyl chain increasing, which was verified by the contact angle of the liquid and the surface. The study indicated that the THz image might offer a potential technique for detecting the wettability of liquid directly without an additional contact angle experiment.

  20. Isolation, identification and characterization of Bacillus amyloliquefaciens BZ-6, a bacterial isolate for enhancing oil recovery from oily sludge.

    Science.gov (United States)

    Liu, Wuxing; Wang, Xiaobing; Wu, Longhua; Chen, Mengfang; Tu, Chen; Luo, Yongming; Christie, Peter

    2012-06-01

    Over 100 biosurfactant-producing microorganisms were isolated from oily sludge and petroleum-contaminated soil from Shengli oil field in north China. Sixteen of the bacterial isolates produced biosurfactants and reduced the surface tension of the growth medium from 71 to treat oily sludge and the recovery efficiencies of oil from oily sludge were determined. The oil recovery efficiencies of different isolates ranged from 39% to 88%. Bacterial isolate BZ-6 was found to be the most efficient strain and the three phases (oil, water and sediment) were separated automatically after the sludge was treated with the culture medium of BZ-6. Based on morphological, physiological characteristics and molecular identification, isolate BZ-6 was identified as Bacillus amyloliquefaciens. The biosurfactant produced by isolate BZ-6 was purified and analyzed by high performance liquid chromatography-electrospray ionization tandem mass spectrometry. There were four ion peaks representing four different fengycin A homologues. Copyright © 2012. Published by Elsevier Ltd.

  1. Development and evaluation of single domain antibodies for vaccinia and the L1 antigen.

    Directory of Open Access Journals (Sweden)

    Scott A Walper

    Full Text Available There is ongoing interest to develop high affinity, thermal stable recognition elements to replace conventional antibodies in biothreat detection assays. As part of this effort, single domain antibodies that target vaccinia virus were developed. Two llamas were immunized with killed viral particles followed by boosts with the recombinant membrane protein, L1, to stimulate the immune response for envelope and membrane proteins of the virus. The variable domains of the induced heavy chain antibodies were selected from M13 phage display libraries developed from isolated RNA. Selection via biopanning on the L1 antigen produced single domain antibodies that were specific and had affinities ranging from 4×10(-9 M to 7.0×10(-10 M, as determined by surface plasmon resonance. Several showed good ability to refold after heat denaturation. These L1-binding single domain antibodies, however, failed to recognize the killed vaccinia antigen. Useful vaccinia binding single domain antibodies were isolated by a second selection using the killed virus as the target. The virus binding single domain antibodies were incorporated in sandwich assays as both capture and tracer using the MAGPIX system yielding limits of detection down to 4×10(5 pfu/ml, a four-fold improvement over the limit obtained using conventional antibodies. This work demonstrates the development of anti-vaccinia single domain antibodies and their incorporation into sandwich assays for viral detection. It also highlights the properties of high affinity and thermal stability that are hallmarks of single domain antibodies.

  2. Social Isolation among Caregivers of Court-Involved Youths: A Qualitative Investigation

    Science.gov (United States)

    Forsbrey, April D.; Frabutt, James M.; Smith, Heather L.

    2005-01-01

    The authors used qualitative research methodology to examine the lives of caregivers of court-involved youths. Caregiver social isolation, including overall lack of support, lack of school support, and isolation from self, emerged as a salient theme across 7 domains. Implications for counselors are discussed, and brief descriptions of several…

  3. The human escort protein Hep binds to the ATPase domain of mitochondrial hsp70 and regulates ATP hydrolysis.

    Science.gov (United States)

    Zhai, Peng; Stanworth, Crystal; Liu, Shirley; Silberg, Jonathan J

    2008-09-19

    Hsp70 escort proteins (Hep) have been implicated as essential for maintaining the function of yeast mitochondrial hsp70 molecular chaperones (mtHsp70), but the role that escort proteins play in regulating mammalian chaperone folding and function has not been established. We present evidence that human mtHsp70 exhibits limited solubility due to aggregation mediated by its ATPase domain and show that human Hep directly enhances chaperone solubility through interactions with this domain. In the absence of Hep, mtHsp70 was insoluble when expressed in Escherichia coli, as was its isolated ATPase domain and a chimera having this domain fused to the peptide-binding domain of HscA, a soluble monomeric chaperone. In contrast, these proteins all exhibited increased solubility when expressed in the presence of Hep. In vitro studies further revealed that purified Hep regulates the interaction of mtHsp70 with nucleotides. Full-length mtHsp70 exhibited slow intrinsic ATP hydrolysis activity (6.8+/-0.2 x 10(-4) s(-1)) at 25 degrees C, which was stimulated up to 49-fold by Hep. Hep also stimulated the activity of the isolated ATPase domain, albeit to a lower maximal extent (11.5-fold). In addition, gel-filtration studies showed that formation of chaperone-escort protein complexes inhibited mtHsp70 self-association, and they revealed that Hep binding to full-length mtHsp70 and its isolated ATPase domain is strongest in the absence of nucleotides. These findings provide evidence that metazoan escort proteins regulate the catalytic activity and solubility of their cognate chaperones, and they indicate that both forms of regulation arise from interactions with the mtHsp70 ATPase domain.

  4. Accumulation of raft lipids in T-cell plasma membrane domains engaged in TCR signalling

    DEFF Research Database (Denmark)

    Zech, Tobias; Ejsing, Christer S.; Gaus, Katharina

    2009-01-01

    Activating stimuli for T lymphocytes are transmitted through plasma membrane domains that form at T-cell antigen receptor (TCR) signalling foci. Here, we determined the molecular lipid composition of immunoisolated TCR activation domains. We observed that they accumulate cholesterol, sphingomyelin...... and saturated phosphatidylcholine species as compared with control plasma membrane fragments. This provides, for the first time, direct evidence that TCR activation domains comprise a distinct molecular lipid composition reminiscent of liquid-ordered raft phases in model membranes. Interestingly, TCR activation...... domains were also enriched in plasmenyl phosphatidylethanolamine and phosphatidylserine. Modulating the T-cell lipidome with polyunsaturated fatty acids impaired the plasma membrane condensation at TCR signalling foci and resulted in a perturbed molecular lipid composition. These results correlate...

  5. Feasibility of a single-parameter description of equilibrium viscous liquid dynamics

    DEFF Research Database (Denmark)

    Pedersen, Ulf Rørbæk; Christensen, Tage Emil; Schrøder, Thomas

    2008-01-01

    Molecular dynamics results for the dynamic Prigogine-Defay ratio are presented for two glass-forming liquids, thus evaluating the experimentally relevant quantity for testing whether metastable-equilibrium liquid dynamics is described by a single parameter to a good approximation. For the Kob......-Andersen binary Lennard-Jones mixture as well as for an asymmetric dumbbell model liquid, a single-parameter description works quite well. This is confirmed by time-domain results where it is found that energy and pressure fluctuations are strongly correlated on the alpha time scale in the constant...

  6. Binding Assays Using Recombinant SH2 Domains: Far-Western, Pull-Down, and Fluorescence Polarization.

    Science.gov (United States)

    Machida, Kazuya; Liu, Bernard

    2017-01-01

    Recognition of phosphotyrosine-containing sequences by SH2 domains confers specificity in tyrosine kinase pathways. By assessing interactions between isolated SH2 domains and their binding proteins, it is possible to gain insight into otherwise inaccessible complex cellular systems. Far-Western, pull-down, and fluorescence polarization (FP) have been frequently used for characterization of phosphotyrosine signaling. Here, we outline standard protocols for these established assays using recombinant SH2 domain, emphasizing the importance of appropriate sample preparation and assay controls.

  7. Selective radiolabeling and isolation of the hydrophobic membrane-binding domain of human erythrocyte acetylcholinesterase

    International Nuclear Information System (INIS)

    Roberts, W.L.; Rosenberry, T.L.

    1986-01-01

    The hydrophobic, membrane-binding domain of purified human erythrocyte acetylcholinesterase was labeled with the photoactivated reagent 3-(trifluoromethyl)-3-(m-[ 125 I]iodophenyl)diazirine. The radiolabel was incorporated when the enzyme was prepared in detergent-free aggregates, in detergent micelles, or in phospholipid liposomes, but the highest percentage of labeling occurred in the detergent-free aggregates. Papain digestion of the enzyme released the hydrophobic domain, and polyacrylamide gel electrophoresis in sodium dodecyl sulfate or gel exclusion chromatography demonstrated that the label was localized exclusively in the cleaved hydrophobic domain fragment. This fragment was purified in a three-step procedure. Digestion was conducted with papain attached to Sepharose CL-4B, and the supernatant was adsorbed to acridinium affinity resin to remove the hydrophilic enzyme fragment. The nonretained fragment associated with Triton X-100 micelles was then chromatographed on Sepharose CL-6B, and finally detergent was removed by chromatography on Sephadex LH-60 in an ethanol-formic acid solvent. The fragment exhibited an apparent molecular weight of 3100 on the Sephadex LH-60 column when compared with peptide standards. However, amino acid analysis of the purified fragment revealed only 1 mol each of histidine and glycine per mole of fragment in contrast to the 25-30 mole of amino acids expected on the basis of the molecular weight estimate. This result suggests a novel non-amino acid structure for the hydrophobic domain of human erythrocyte acetylcholinesterase

  8. Size and mobility of lipid domains tuned by geometrical constraints.

    Science.gov (United States)

    Schütte, Ole M; Mey, Ingo; Enderlein, Jörg; Savić, Filip; Geil, Burkhard; Janshoff, Andreas; Steinem, Claudia

    2017-07-25

    In the plasma membrane of eukaryotic cells, proteins and lipids are organized in clusters, the latter ones often called lipid domains or "lipid rafts." Recent findings highlight the dynamic nature of such domains and the key role of membrane geometry and spatial boundaries. In this study, we used porous substrates with different pore radii to address precisely the extent of the geometric constraint, permitting us to modulate and investigate the size and mobility of lipid domains in phase-separated continuous pore-spanning membranes (PSMs). Fluorescence video microscopy revealed two types of liquid-ordered ( l o ) domains in the freestanding parts of the PSMs: ( i ) immobile domains that were attached to the pore rims and ( ii ) mobile, round-shaped l o domains within the center of the PSMs. Analysis of the diffusion of the mobile l o domains by video microscopy and particle tracking showed that the domains' mobility is slowed down by orders of magnitude compared with the unrestricted case. We attribute the reduced mobility to the geometric confinement of the PSM, because the drag force is increased substantially due to hydrodynamic effects generated by the presence of these boundaries. Our system can serve as an experimental test bed for diffusion of 2D objects in confined geometry. The impact of hydrodynamics on the mobility of enclosed lipid domains can have great implications for the formation and lateral transport of signaling platforms.

  9. Numerical study of liquid crystal elastomers by a mixed finite element method

    KAUST Repository

    LUO, C.

    2011-08-22

    Liquid crystal elastomers present features not found in ordinary elastic materials, such as semi-soft elasticity and the related stripe domain phenomenon. In this paper, the two-dimensional Bladon-Terentjev-Warner model and the one-constant Oseen-Frank energy expression are combined to study the liquid crystal elastomer. We also impose two material constraints, the incompressibility of the elastomer and the unit director norm of the liquid crystal. We prove existence of minimiser of the energy for the proposed model. Next we formulate the discrete model, and also prove that it possesses a minimiser of the energy. The inf-sup values of the discrete linearised system are then related to the smallest singular values of certain matrices. Next the existence and uniqueness of the Lagrange multipliers associated with the two material constraints are proved under the assumption that the inf-sup conditions hold. Finally numerical simulations of the clamped-pulling experiment are presented for elastomer samples with aspect ratio 1 or 3. The semi-soft elasticity is successfully recovered in both cases. The stripe domain phenomenon, however, is not observed, which might be due to the relative coarse mesh employed in the numerical experiment. Possible improvements are discussed that might lead to the recovery of the stripe domain phenomenon. © Copyright Cambridge University Press 2011.

  10. Isolasi, Seleksi Dan Opttmasi Produksi Protease Daribeberapaisolat Bakteri*(isolation, Selection and Optimalization of Protease Production of Some Bacterial Isolates)

    OpenAIRE

    Naiola, Elidar; Widhyastuti, Nunuk

    2002-01-01

    Thirty-seven out of sixty-one bacterial isolates from various sources of samples were screened for protease production. The isolate of ISO PL3 could produce the highest enzyme activity, and it was used as a standard bacterial strain in this observation. For any reason,we implemented ISO PL2 to study the optimum condition for producing bacterial protease. Result shows that the maximum protease activity was obtained in a medium containing 100 gram of rice brand in a liter tofu liquid waste. The...

  11. Computational split-field finite-difference time-domain evaluation of simplified tilt-angle models for parallel-aligned liquid-crystal devices

    Science.gov (United States)

    Márquez, Andrés; Francés, Jorge; Martínez, Francisco J.; Gallego, Sergi; Álvarez, Mariela L.; Calzado, Eva M.; Pascual, Inmaculada; Beléndez, Augusto

    2018-03-01

    Simplified analytical models with predictive capability enable simpler and faster optimization of the performance in applications of complex photonic devices. We recently demonstrated the most simplified analytical model still showing predictive capability for parallel-aligned liquid crystal on silicon (PA-LCoS) devices, which provides the voltage-dependent retardance for a very wide range of incidence angles and any wavelength in the visible. We further show that the proposed model is not only phenomenological but also physically meaningful, since two of its parameters provide the correct values for important internal properties of these devices related to the birefringence, cell gap, and director profile. Therefore, the proposed model can be used as a means to inspect internal physical properties of the cell. As an innovation, we also show the applicability of the split-field finite-difference time-domain (SF-FDTD) technique for phase-shift and retardance evaluation of PA-LCoS devices under oblique incidence. As a simplified model for PA-LCoS devices, we also consider the exact description of homogeneous birefringent slabs. However, we show that, despite its higher degree of simplification, the proposed model is more robust, providing unambiguous and physically meaningful solutions when fitting its parameters.

  12. Sarcocystis neurona: molecular characterization of enolase domain I region and a comparison to other protozoa.

    Science.gov (United States)

    Bolten, K E; Marsh, A E; Reed, S M; Dubey, J P; Toribio, R E; Saville, W J A

    2008-09-01

    Sarcocystis neurona causes protozoal myeloencephalitis and has the ability to infect a wide host range in contrast to other Sarcocystis species. In the current study, five S. neurona isolates from a variety of sources, three Sarcocystis falcatula, one Sarcocystis dasypi/S. neurona-like isolate, and one Besnoitia darlingi isolate were used to compare the enolase 2 gene segment containing the domain I region to previously sequenced enolase genes from Neospora caninum, Neospora hughesi, Toxoplasma gondii, Plasmodium falciparum, and Trypanosoma cruzi; enolase 2 segment containing domain I region is highly conserved amongst these parasites of veterinary and medical importance. Immunohistochemistry results indicates reactivity of T. gondii enolase 1 and 2 antibodies to S. neurona merozoites and metrocytes, but no reactivity of anti-enolase 1 to the S. neurona bradyzoite stage despite reactivity to T. gondii bradyzoites, suggesting expression differences between organisms.

  13. Aspirin locally disrupts the liquid-ordered phase

    Science.gov (United States)

    Alsop, Richard J.; Himbert, Sebastian; Dhaliwal, Alexander; Schmalzl, Karin; Rheinstädter, Maikel C.

    2018-02-01

    Local structure and dynamics of lipid membranes play an important role in membrane function. The diffusion of small molecules, the curvature of lipids around a protein and the existence of cholesterol-rich lipid domains (rafts) are examples for the membrane to serve as a functional interface. The collective fluctuations of lipid tails, in particular, are relevant for diffusion of membrane constituents and small molecules in and across membranes, and for structure and formation of membrane domains. We studied the effect of aspirin (acetylsalicylic acid, ASA) on local structure and dynamics of membranes composed of dimyristoylphosphocholine (DMPC) and cholesterol. Aspirin is a common analgesic, but is also used in the treatment of cholesterol. Using coherent inelastic neutron scattering experiments and molecular dynamics (MD) simulations, we present evidence that ASA binds to liquid-ordered, raft-like domains and disturbs domain organization and dampens collective fluctuations. By hydrogen-bonding to lipid molecules, ASA forms `superfluid' complexes with lipid molecules that can organize laterally in superlattices and suppress cholesterol's ordering effect.

  14. Effect of temperature on the morphology and electro-optical properties of liquid crystal physical gel

    International Nuclear Information System (INIS)

    Leaw, W.L.; Mamat, C.R.; Triwahyono, S.; Jalil, A.A.; Bidin, N.

    2016-01-01

    Liquid crystal physical gels were (thermally) prepared with cholesteryl stearate as a gelator in nematic liquid crystal, 4-cyano-4′-pentylbiphenyl. The electro-optical performance of liquid crystal physical gels is almost entirely dependent on the gels' inherent morphology. This study involved an empirical investigation of the relationships among all of the gelation temperature, morphology, and electro-optical properties. Besides continuous cooling at room temperature, isothermal cooling was also performed at both 18 and 0 °C, corresponding to near-solid and solid phases of 4-cyano-4′-pentylbiphenyl respectively. Nevertheless, the liquid crystal physical gel was also isothermally rapidly cooled using liquid nitrogen. Polarizing optical microscopy showed that the gel structure became thinner when isothermal cooling was carried out. These thinner gel aggregates then interconnected to form larger liquid crystal domains. Moreover, it was also revealed that the gel networks were randomized. Electron spin resonance results showed that the liquid crystal director orientation was severely randomized in the presence of gel networks. Conversely, isothermal cooling using liquid nitrogen generated a higher liquid crystal director orientation order. The 6.0 wt% cholesteryl stearate/4-cyano-4′-pentylbiphenyl physical gel that was isothermally cooled using liquid nitrogen showed the lowest response time in a twisted nematic mode optical cell. - Graphical abstract: Liquid crystal physical gel was prepared using nematic liquid crystal, 4-cyano-4′-pentylbiphenyl and cholesteryl stearate as gelator. Isothermal cooling at lower temperature produced thinner gel network and larger liquid crystal domain. - Highlights: • 5CB nematic liquid crystal was successfully gelled by cholesteryl stearate gelator. • The morphology of gel network was controlled by different cooling conditions. • Thinner gel network was formed by the rapid cooling using liquid nitrogen. • Enhanced

  15. Effect of temperature on the morphology and electro-optical properties of liquid crystal physical gel

    Energy Technology Data Exchange (ETDEWEB)

    Leaw, W.L. [Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310, UTM Johor Bahru, Johor (Malaysia); Mamat, C.R., E-mail: che@kimia.fs.utm.my [Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310, UTM Johor Bahru, Johor (Malaysia); Triwahyono, S. [Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310, UTM Johor Bahru, Johor (Malaysia); Jalil, A.A. [Department of Chemical Engineering, Faculty of Chemical and Energy Engineering, Universiti Teknologi Malaysia, 81310, UTM Johor Bahru, Johor (Malaysia); Centre of Hydrogen Energy, Institute of Future Energy, Univerisiti Teknologi Malaysia, 81310, UTM Johor Bahru, Johor (Malaysia); Bidin, N. [Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, 81310, UTM Johor Bahru, Johor (Malaysia)

    2016-12-01

    Liquid crystal physical gels were (thermally) prepared with cholesteryl stearate as a gelator in nematic liquid crystal, 4-cyano-4′-pentylbiphenyl. The electro-optical performance of liquid crystal physical gels is almost entirely dependent on the gels' inherent morphology. This study involved an empirical investigation of the relationships among all of the gelation temperature, morphology, and electro-optical properties. Besides continuous cooling at room temperature, isothermal cooling was also performed at both 18 and 0 °C, corresponding to near-solid and solid phases of 4-cyano-4′-pentylbiphenyl respectively. Nevertheless, the liquid crystal physical gel was also isothermally rapidly cooled using liquid nitrogen. Polarizing optical microscopy showed that the gel structure became thinner when isothermal cooling was carried out. These thinner gel aggregates then interconnected to form larger liquid crystal domains. Moreover, it was also revealed that the gel networks were randomized. Electron spin resonance results showed that the liquid crystal director orientation was severely randomized in the presence of gel networks. Conversely, isothermal cooling using liquid nitrogen generated a higher liquid crystal director orientation order. The 6.0 wt% cholesteryl stearate/4-cyano-4′-pentylbiphenyl physical gel that was isothermally cooled using liquid nitrogen showed the lowest response time in a twisted nematic mode optical cell. - Graphical abstract: Liquid crystal physical gel was prepared using nematic liquid crystal, 4-cyano-4′-pentylbiphenyl and cholesteryl stearate as gelator. Isothermal cooling at lower temperature produced thinner gel network and larger liquid crystal domain. - Highlights: • 5CB nematic liquid crystal was successfully gelled by cholesteryl stearate gelator. • The morphology of gel network was controlled by different cooling conditions. • Thinner gel network was formed by the rapid cooling using liquid nitrogen.

  16. Resolution of RNA using high-performance liquid chromatography

    NARCIS (Netherlands)

    Mclaughlin, L.W.; Bischoff, Rainer

    1987-01-01

    High-performance liquid chromatographic techniques can be very effective for the resolution and isolation of nucleic acids. The characteristic ionic (phosphodiesters) and hydrophobic (nucleobases) properties of RNAs can be exploited for their separation. In this respect anion-exchange and

  17. Laser-induced microscopic phase-transition on an ionic liquid

    International Nuclear Information System (INIS)

    Iguchi, Natsuki; Datta, Alokmay; Yoshikawa, Kenichi; Ma Yue

    2009-01-01

    Nematic-isotropic transition is induced in a 5 μm 'droplet' within an oriented bulk of a mixture of a liquid crystalline material with a room-temperature ionic liquid, by a laser working at 532 nm with an output power of 200 mW and a beam diameter of 1 μm. No microscopic phase transition is observed either in absence of the ionic liquid or at the other wavelength of 1064 nm, available to the Nd-YAG laser. This indicates the essential role on a resonant transfer of energy to the ionic liquid from the laser radiation, which is subsequently transferred to the liquid crystal. Spectroscopy of the pure liquid crystal and ionic liquid samples confirms this concept. Spatio-temporal image of the droplet growth shows, however, that the phase transition remains confined within the microscopic domain for the first 50 s, and then spreads out rapidly. Since resonant, quantum transitions between molecular levels takes place in less than microseconds, the about seven orders of magnitude slowing down of energy transfer observed here suggests unique hierarchical dynamics including the coupling between the intra-molecular motions in the ionic liquid and the inter-molecular forces between ionic liquid and liquid crystal.

  18. Hydrocarbon-degrading bacteria isolation and surfactant influence ...

    African Journals Online (AJOL)

    Hydrocarbons are substantially insoluble in water, often remaining partitioned in the non-aqueous phase liquid (NAPL). However, there had been little or no attempts to advance the bioavailability of hydrocarbons through the use of surfactants. This study was conducted based on the need to isolate hydrocarbon degrading ...

  19. The Human Escort Protein Hep Binds to the ATPase Domain of Mitochondrial Hsp70 and Regulates ATP Hydrolysis*

    Science.gov (United States)

    Zhai, Peng; Stanworth, Crystal; Liu, Shirley; Silberg, Jonathan J.

    2008-01-01

    Hsp70 escort proteins (Hep) have been implicated as essential for maintaining the function of yeast mitochondrial hsp70 molecular chaperones (mtHsp70), but the role that escort proteins play in regulating mammalian chaperone folding and function has not been established. We present evidence that human mtHsp70 exhibits limited solubility due to aggregation mediated by its ATPase domain and show that human Hep directly enhances chaperone solubility through interactions with this domain. In the absence of Hep, mtHsp70 was insoluble when expressed in Escherichia coli, as was its isolated ATPase domain and a chimera having this domain fused to the peptide-binding domain of HscA, a soluble monomeric chaperone. In contrast, these proteins all exhibited increased solubility when expressed in the presence of Hep. In vitro studies further revealed that purified Hep regulates the interaction of mtHsp70 with nucleotides. Full-length mtHsp70 exhibited slow intrinsic ATP hydrolysis activity (6.8 ± 0.2 × 10-4 s-1) at 25 °C, which was stimulated up to 49-fold by Hep. Hep also stimulated the activity of the isolated ATPase domain, albeit to a lower maximal extent (11.5-fold). In addition, gel-filtration studies showed that formation of chaperone-escort protein complexes inhibited mtHsp70 self-association, and they revealed that Hep binding to full-length mtHsp70 and its isolated ATPase domain is strongest in the absence of nucleotides. These findings provide evidence that metazoan escort proteins regulate the catalytic activity and solubility of their cognate chaperones, and they indicate that both forms of regulation arise from interactions with the mtHsp70 ATPase domain. PMID:18632665

  20. Isolation and Purification of Unstable Iridoid Glucosides from Traditional Chinese Medicine by Preparative High Performance Liquid Chromatography Coupled with Solid-phase Extraction

    Institute of Scientific and Technical Information of China (English)

    LI Cun-man; XIAO Yuan-sheng; XUE Xing-ya; FENG Jia-tao; ZHANG Xiu-li; LIANG Xin-miao

    2011-01-01

    An efficient preparative method was successfully developed for isolation and purification of unstable components from medicinal plant extracts, using a combined method of preparative high performance liquid chro matography(HPLC) and solid-phase extraction(SPE). The aim of this study was to obtain an effective method with high preparative efficiency and importantly to avoid the transformation of unstable compounds. The preparative HPLC system was based on an LC/MS controlled four-channel autopurification system. The SPE method was per formed with a C1s packing material to trap the target compounds and to remove the acidic additive derived from the mobile phase. Using this method, the unstable iridoid glucosides(IGs) as model compounds were successfully iso lated and purified from the extract of Hedyotis diffusa Willd. Six IGs(including one new minor IG) and one nucleo tide compound were simultaneously obtained, each with a purity of >91% as determined by HPLC. The structures of the isolated compounds were identified by UPLC/Q-TOF MS, UV, ID and/or 2D NMR. It was demonstrated that the combination of preparative HPLC with SPE is a versatile tool for preparative purification of unstable compounds from complex natural products.

  1. Properties of gases, liquids, and solutions principles and methods

    CERN Document Server

    Mason, Warren P

    2013-01-01

    Physical Acoustics: Principles and Methods, Volume ll-Part A: Properties of Gases, Liquids, and Solutions ponders on high frequency sound waves in gases, liquids, and solids that have been proven as effective tools in examining the molecular, domain wall, and other types of motions. The selection first offers information on the transmission of sound waves in gases at very low pressures and the phenomenological theory of the relaxation phenomena in gases. Topics include free molecule propagation, phenomenological thermodynamics of irreversible processes, and simultaneous multiple relaxation pro

  2. Multi-User Domain Object Oriented (MOO) as a High School Procedure for Foreign Language Acquisition.

    Science.gov (United States)

    Backer, James A.

    Foreign language students experience added difficulty when they are isolated from native speakers and from the culture of the target language. It has been posited that MOO (Multi-User Domain Object Oriented) may help overcome the geographical isolation of these students. MOOs are Internet-based virtual worlds in which people from all over the real…

  3. In vitro degradation of linamarin by microorganisms isolated from cassava wastewater treatment lagoons

    Directory of Open Access Journals (Sweden)

    S. P Vasconcellos

    2009-12-01

    Full Text Available This study aimed at isolating and characterizing of microorganisms able to use linamarin as sole carbon source. Thirty one microbial strains were isolated from manipueira, a liquid effluent of cassava processing factories. Among these strains, Bacillus licheniformis (isolate 2_2 and Rhodotorulla glutinis (isolate L1 were able to degrade 71% and 95% of added linamarin, respectively, within 7 days, showing high biodegradation activity and great potential for detoxification of cassava processing wastewaters.

  4. A Method to Identify Nucleolus-Associated Chromatin Domains (NADs).

    Science.gov (United States)

    Carpentier, Marie-Christine; Picart-Picolo, Ariadna; Pontvianne, Frédéric

    2018-01-01

    The nuclear context needs to be taken into consideration to better understand the mechanisms shaping the epigenome and its organization, and therefore its impact on gene expression. For example, in Arabidopsis, heterochromatin is preferentially localized at the nuclear and the nucleolar periphery. Although chromatin domains associating with the nuclear periphery remain to be identified in plant cells, Nucleolus Associated chromatin Domains (NADs) can be identified thanks to a protocol allowing the isolation of pure nucleoli. We describe here the protocol enabling the identification of NADs in Arabidopsis. Providing the transfer of a nucleolus marker as described here in other crop species, this protocol is broadly applicable.

  5. Microbial F-type lectin domains with affinity for blood group antigens.

    Science.gov (United States)

    Mahajan, Sonal; Khairnar, Aasawari; Bishnoi, Ritika; Ramya, T N C

    2017-09-23

    F-type lectins are fucose binding lectins with characteristic fucose binding and calcium binding motifs. Although they occur with a selective distribution in viruses, prokaryotes and eukaryotes, most biochemical studies have focused on vertebrate F-type lectins. Recently, using sensitive bioinformatics search techniques on the non-redundant database, we had identified many microbial F-type lectin domains with diverse domain organizations. We report here the biochemical characterization of F-type lectin domains from Cyanobium sp. PCC 7001, Myxococcus hansupus and Leucothrix mucor. We demonstrate that while all these three microbial F-type lectin domains bind to the blood group H antigen epitope on fucosylated glycans, there are fine differences in their glycan binding specificity. Cyanobium sp. PCC 7001 F-type lectin domain binds exclusively to extended H type-2 motif, Myxococcus hansupus F-type lectin domain binds to B, H type-1 and Lewis b motifs, and Leucothrix mucor F-type lectin domain binds to a wide range of fucosylated glycans, including A, B, H and Lewis antigens. We believe that these microbial lectins will be useful additions to the glycobiologist's toolbox for labeling, isolating and visualizing glycans. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Rational approach to solvent system selection for liquid-liquid extraction-assisted sample pretreatment in counter-current chromatography.

    Science.gov (United States)

    Wang, Jiajia; Gu, Dongyu; Wang, Miao; Guo, Xinfeng; Li, Haoquan; Dong, Yue; Guo, Hong; Wang, Yi; Fan, Mengqi; Yang, Yi

    2017-05-15

    A rational liquid-liquid extraction approach was established to pre-treat samples for high-speed counter-current chromatography (HSCCC). n-Hexane-ethyl acetate-methanol-water (4:5:4:5, v/v) and (1:5:1:5, v/v) were selected as solvent systems for liquid-liquid extraction by systematically screening K of target compounds to remove low- and high-polarity impurities in the sample, respectively. After liquid-liquid extraction was performed, 1.4g of crude sample II was obtained from 18.5g of crude sample I which was extracted from the flowers of Robinia pseudoacacia L., and then separated with HSCCC by using a solvent system composed of n-hexane-ethyl acetate-methanol-water (1:2:1:2, v/v). As a result, 31mg of robinin and 37mg of kaempferol 7-O-α-l-rhamnopyranoside were isolated from 200mg of crude sample II in a single run of HSCCC. A scale-up separation was also performed, and 160mg of robinin with 95% purity and 188mg of kaempferol 7-O-α-l-rhamnopyranoside with 97% purity were produced from 1.2g of crude sample II. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Isolation, Identification and Determination of Six Nucleosides and ...

    African Journals Online (AJOL)

    Methods: The compounds in bamboo shoots were isolated and identified by ultraviolet (UV) spectroscopy, mass spectrometry (MS), and nuclear magnetic resonance (NMR). Quantitative analysis was performed by reversed-phase high performance liquid chromatography (RP-HPLC) using a C18 column and a mixture ...

  8. FSI-based Overflow Assessment of the Seismically-Isolated SFP with Fuel Racks

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Gil Y.; Park, Hyun T.; Chang, Soo-Hyuk [Korea Maintenance Co., Seoul (Korea, Republic of); Lee, Sang-Hoon [KEPCO E-C, Yongin (Korea, Republic of)

    2014-10-15

    To date, effectiveness of the seismic isolation systems for reducing seismic force effectively has been well demonstrated. In this context, practical application of the technology in nuclear engineering fields has become an important issue more and more. This is because fluid motion can be rather amplified due to the increased relative displacement between the base and superstructures by a long-period shift. Therefore, overflow assessment and prediction of the seismically-isolated SFP have to be conducted in design phase. For performing sloshing-induced overflow of the seismically-isolated SFP, a fluid-structure interaction(FSI) approach making a two-way coupling process between structural and fluid solvers is herein employed. In this study, fuel racks inside the SFP are included in FSI modeling to investigate effect of fuel-cell assemblies on SFP overflow. Accordingly, three different assembly sets of fuel cells are assumed to be inserted in fuel racks. In addition, floor acceleration time-histories produced from three different amplitudes of peak ground acceleration (PGA) are applied to the SFP base to investigate load effect on liquid overflow. An approach for the liquid overflow assessment of the seismically-isolated nuclear SFP with fuel storage racks based on FSI analysis was addressed. From the results of the identified cases, the following conclusions are drawn: (i) FSI technique can be effectively used to assess the seismically-isolated SFP overflow, (ii) In a conservative way, the isolated SFP without fuel racks can be used to assess its sloshing-induced overflow under earthquake since effect of fuel-cell assemblies on the SFP overflow is not significant, (iii) for given same conditions (e.g., constant design free surface, same fuel-cell assembly) except seismic loading, the higher PGA is, the more liquid overflow increases.

  9. Hysteresis loop design by geometry of garnet film element with single domain wall

    International Nuclear Information System (INIS)

    Skidanov, V A; Vetoshko, P M; Stempkovskiy, A L

    2011-01-01

    Numerical modeling and experimental investigation of magnetostatic stable states of two-domain structure in Bi-substituted uniaxial garnet film elements was made. Single domain walls (DW) between two opposite normally magnetized parts in isolated rectangular strip and strip-like bridge are found to exhibit different behavior. DW inside strip (bridge) suffers increasing repulsion (attraction) from nearest edge when shifted from element center. DW position center position is stable in isolated strip but bridge is magnetized spontaneously to one of two saturated states in zero external field. Isolated strip magnetization process occurs reversibly while bridge magnetization reversal occurs by coercive manner. Strip susceptibility and bridge coercive field are entirely defined by magnetostatic barrier created by element boundary stray field in case of constant DW length during magnetization reversal. Variation of strip and bridge boundary shape along DW trajectory gives the opportunity to create additional controllable potential profile due to DW surface energy modulation by DW length. Garnet elements with high Faraday rotation and low light switching field were developed for fine magnetic sensing and optical data processing applications.

  10. A Microwave Tunable Bandpass Filter for Liquid Crystal Applications

    Science.gov (United States)

    Cao, Weiping; Jiang, Di; Liu, Yupeng; Yang, Yuanwang; Gan, Baichuan

    2017-07-01

    In this paper, a novel microwave continuously tunable band-pass filter, based on nematic liquid crystals (LCs), is proposed. It uses liquid crystal (LC) as the electro-optic material to mainly realize frequency shift at microwave band by changing the dielectric anisotropy, when applying the bias voltage. According to simulation results, it achieves 840 MHz offset. Comparing to the existing tunable filter, it has many advantages, such as continuously tunable, miniaturization, low processing costs, low tuning voltage, etc. Thus, it has shown great potentials in frequency domain and practical applications in modern communication.

  11. Isolation of Single-Domain Antibody Fragments That Preferentially Detect Intact (146S Particles of Foot-and-Mouth Disease Virus for Use in Vaccine Quality Control

    Directory of Open Access Journals (Sweden)

    Michiel M. Harmsen

    2017-08-01

    Full Text Available Intact (146S foot-and-mouth disease virus (FMDVs can dissociate into specific (12S viral capsid degradation products. FMD vaccines normally consist of inactivated virions. Vaccine quality is dependent on 146S virus particles rather than 12S particles. We earlier isolated two llama single-domain antibody fragments (VHHs that specifically recognize 146S particles of FMDV strain O1 Manisa and shown their potential use in quality control of FMD vaccines during manufacturing. These 146S-specific VHHs were specific for particular O serotype strains and did not bind strains from other FMDV serotypes. Here, we describe the isolation of 146S-specific VHHs against FMDV SAT2 and Asia 1 strains by phage display selection from llama immune libraries. VHHs that bind both 12S and 146S particles were readily isolated but VHHs that bind specifically to 146S particles could only be isolated by phage display selection using prior depletion for 12S particles. We obtained one 146S-specific VHH—M332F—that binds to strain Asia 1 Shamir and several VHHs that preferentially bind 146S particles of SAT2 strain SAU/2/00, from which we selected VHH M379F for further characterization. Both M332F and M379F did not bind FMDV strains from other serotypes. In a sandwich enzyme-linked immunosorbent assay (ELISA employing unlabeled and biotinylated versions of the same VHH M332F showed high specificity for 146S particles but M379F showed lower 146S-specificity with some cross-reaction with 12S particles. These ELISAs could detect 146S particle concentrations as low as 2.3–4.6 µg/l. They can be used for FMD vaccine quality control and research and development, for example, to identify virion stabilizing excipients.

  12. Characterization of the domains of E. coli initiation factor IF2 responsible for recognition of the ribosome

    DEFF Research Database (Denmark)

    Manuel Palacios Moreno, Juan; Andersen, Lars Dyrskjøt; Egebjerg Kristensen, Janni

    1999-01-01

    We have studied the interactions between the ribosome and the domains of Escherichia coli translation initiation factor 2, using an in vitro ribosomal binding assay with wild-type forms, N- and C-terminal truncated forms of IF2 as well as isolated structural domains. A deletion mutant of the factor...

  13. Characterization of the domains of E. coli initiation factor IF2 responsible for recognition of the ribosome

    DEFF Research Database (Denmark)

    Manuel Palacios Moreno, Juan; Andersen, Lars Dyrskjøt; Egebjerg Kristensen, Janni

    1999-01-01

    We have studied the interactions between the ribosome and the domains of Escherichia coli translation initiation factor 2, using an in vitro ribosomal binding assay with wild-type forms, N- and C-terminal truncated forms of IF2 as well as isolated structural domains. A deletion mutant of the fact...

  14. UV-guided isolation of fungal metabolites by HSCCC

    DEFF Research Database (Denmark)

    Dalsgaard, P.W.; Nielsen, K.F.; Larsen, Thomas Ostenfeld

    2005-01-01

    Analytical standardised reversed phase liquid chromatography (RPLC) data can be helpful in finding a suitable solvent combination for isolation of fungal metabolites by high-speed counter current chromatography. Analysis of the distribution coefficient (K-D) of fungal metabolites in a series...... peptides from a crude fungal extract....

  15. Selection and characterization of naturally occurring single-domain (IgNAR) antibody fragments from immunized sharks by phage display.

    Science.gov (United States)

    Dooley, Helen; Flajnik, Martin F; Porter, Andrew J

    2003-09-01

    The novel immunoglobulin isotype novel antigen receptor (IgNAR) is found in cartilaginous fish and is composed of a heavy-chain homodimer that does not associate with light chains. The variable regions of IgNAR function as independent domains similar to those found in the heavy-chain immunoglobulins of Camelids. Here, we describe the successful cloning and generation of a phage-displayed, single-domain library based upon the variable domain of IgNAR. Selection of such a library generated from nurse sharks (Ginglymostoma cirratum) immunized with the model antigen hen egg-white lysozyme (HEL) enabled the successful isolation of intact antigen-specific binders matured in vivo. The selected variable domains were shown to be functionally expressed in Escherichia coli, extremely stable, and bind to antigen specifically with an affinity in the nanomolar range. This approach can therefore be considered as an alternative route for the isolation of minimal antigen-binding fragments with favorable characteristics.

  16. Apparatus for sealing a rotatable shield plug in a liquid metal nuclear reactor

    International Nuclear Information System (INIS)

    Winkleblack, R.K.

    1980-01-01

    An apparatus for sealing a rotatable shield plug in a nuclear reactor having liquid metal coolant is described. The apparatus includes a dip -ring seal adapted to provide a fluid barrier between the liquid metal and the atmosphere and to permit rotation of the shield plug. The apparatus also includes a static seal for the rotatable shield plug located between the dip-ring seal and the liquid metal. The static seal isolates the dip-ring seal from the liquid metal vapor during operation at power and can be disengaged for rotation of the shield plug

  17. Effect of Sample Preparation on the Discrimination of Bacterial Isolates Cultured in Liquid Nutrient Media Using Laser-Induced Breakdown Spectroscopy (LIBS).

    Science.gov (United States)

    Gamble, Gary R; Park, Bosoon; Yoon, Seung-Chul; Lawrence, Kurt C

    2016-03-01

    Laser-induced breakdown spectroscopy (LIBS) is used as the basis for discrimination between two genera of gram-negative bacteria and two genera of gram-positive bacteria representing pathogenic threats commonly found in poultry processing rinse waters. Because LIBS-based discrimination relies primarily upon the relative proportions of inorganic cell components including Na, K, Mg, and Ca, this study aims to determine the effects of trace mineral content and pH found in the water source used to isolate the bacteria upon the reliability of the resulting discriminant analysis. All four genera were cultured using tryptic soy agar (TSA) as the nutrient medium, and were grown under identical environmental conditions. The only variable introduced is the source water used to isolate the cultured bacteria. Cultures of each bacterium were produced using deionized (DI) water under two atmosphere conditions, reverse osmosis (RO) water, tap water, phosphate buffered saline (PBS) water, and TRIS buffered water. After 3 days of culture growth, the bacteria were centrifuged and washed three times in the same water source. Bacteria were then freeze dried, mixed with microcrystalline cellulose, and a pellet was made for LIBS analysis. Principal component analysis (PCA) was used to extract related variations in LIBS spectral data among the four bacteria genera and six water types used to isolate the bacteria, and Mahalanobis discriminant analysis (MDA) was used for classification. Results indicate not only that the four genera can be discriminated from each other in each water type, but that each genus can be discriminated by water type used for isolation. It is concluded that in order for LIBS to be a reliable and repeatable method for discrimination of bacteria grown in liquid nutrient media, care must be taken to insure that the water source used in purification of the culture be precisely controlled regarding pH, ionic strength, and proportionate amounts of mineral cations

  18. Isolation of two tissue-specific Drosophila paired box genes, Pox meso and Pox neuro.

    OpenAIRE

    Bopp, D; Jamet, E; Baumgartner, S; Burri, M; Noll, M

    1989-01-01

    Two new paired domain genes of Drosophila, Pox meso and Pox neuro, are described. In contrast to the previously isolated paired domain genes, paired and gooseberry, which contain both a paired and a homeo-domain (PHox genes), Pox meso and Pox neuro possess no homeodomain. Evidence suggesting that the new genes encode tissue-specific transcriptional factors and belong to the same regulatory cascade as the other paired domain genes includes (i) tissue-specific expression of Pox meso in the soma...

  19. System for sampling liquids in small jugs obturated by screwed taps

    International Nuclear Information System (INIS)

    Besnier, J.

    1995-01-01

    This invention describes a machine which samples automatically liquids in small jugs obturated by screwed taps. This device can be situated in an isolated room in order to work with radioactive liquids. The machine can be divided in three main parts: a module to catch the jug, in order to take and fix it, a module to open and to close it, and a module to sample. The later takes the liquid thanks to a suction device and puts it in a container, in order to analyse the sample. (TEC)

  20. Useful halophilic, thermostable and ionic liquids tolerant cellulases

    Science.gov (United States)

    Zhang, Tao; Datta, Supratim; Simmons, Blake A.; Rubin, Edward M.

    2016-06-28

    The present invention provides for an isolated or recombinant polypeptide comprising an amino acid sequence having at least 70% identity with the amino acid sequence of a Halorhabdus utahensis cellulase, such as Hu-CBH1, wherein said amino acid sequence has a halophilic thermostable and/or thermophilic cellobiohydrolase (CBH) activity. In some embodiments, the polypeptide has a CBH activity that is resistant to up to about 20% of ionic liquids. The present invention also provides for compositions comprising and methods using the isolated or recombinant polypeptide.

  1. Vibrational relaxation in liquids: Comparisons between gas phase and liquid phase theories

    International Nuclear Information System (INIS)

    Russell, D.J.

    1990-12-01

    The vibrational relaxation of iodine in liquid xenon was studied to understand what processes are important in determining the density dependence of the vibrational relaxation. This examination will be accomplished by taking simple models and comparing the results to both experimental outcomes and the predictions of molecular dynamics simulations. The vibration relaxation of iodine is extremely sensitive to the iodine potential. The anharmonicity of iodine causes vibrational relaxation to be much faster at the top of the iodine well compared to the vibrational relaxation at the bottom. A number of models are used in order to test the ability of the Isolated Binary Collision theory's ability to predict the density dependence of the vibrational relaxation of iodine in liquid xenon. The models tested vary from the simplest incorporating only the fact that the solvent occupies volume to models that incorporate the short range structure of the liquid in the radial distribution function. None of the models tested do a good job of predicting the actual relaxation rate for a given density. This may be due to a possible error in the choice of potentials to model the system

  2. Liquid Marbles

    KAUST Repository

    Khalil, Kareem

    2012-12-01

    Granulation, the process of formation of granules from a combination of base powders and binder liquids, has been a subject of research for almost 50 years, studied extensively for its vast applications, primarily to the pharmaceutical industry sector. The principal aim of granulation is to form granules comprised of the active pharmaceutical ingredients (API’s), which have more desirable handling and flowability properties than raw powders. It is also essential to ensure an even distribution of active ingredients within a tablet with the goal of achieving time‐controlled release of drugs. Due to the product‐specific nature of the industry, however, data is largely empirical [1]. For example, the raw powders used can vary in size by two orders of magnitude with narrow or broad size distributions. The physical properties of the binder liquids can also vary significantly depending on the powder properties and required granule size. Some significant progress has been made to better our understanding of the overall granulation process [1] and it is widely accepted that the initial nucleation / wetting stage, when the binder liquid first wets the powders, is key to the whole process. As such, many experimental studies have been conducted in attempt to elucidate the physics of this first stage [1], with two main mechanisms being observed – classified by Ivenson [1] as the “Traditional description” and the “Modern Approach”. See Figure 1 for a graphical definition of these two mechanisms. Recent studies have focused on the latter approach [1] and a new, exciting development in this field is the Liquid Marble. This interesting formation occurs when a liquid droplet interacts with a hydrophobic (or superhydrophobic) powder. The droplet can become encased in the powder, which essentially provides a protective “shell” or “jacket” for the liquid inside [2]. The liquid inside is then isolated from contact with other solids or liquids and has some

  3. Characterisation of lignins isolated from sugarcane bagasse pretreated with acidified ethylene glycol and ionic liquids

    International Nuclear Information System (INIS)

    Moghaddam, Lalehvash; Zhang, Zhanying; Wellard, R. Mark; Bartley, John P.; O'Hara, Ian M.; Doherty, William O.S.

    2014-01-01

    Sugarcane bagasse pretreatment processes using acidified aqueous ethylene glycol (EG) and ionic liquids (ILs) have been reported recently. In this study, recovery of lignins from these processes was conducted, as well as determination of their physico-chemical properties. The amount of lignins recovered from 1-butyl-3-methylimidazolium chloride ([bmim]Cl) with HCl as a catalyst and [bmim][CH 3 SO 3 ] was ∼42%, and ∼35%–36% by EG with HCl or H 2 SO 4 as a catalyst, respectively. The isolated lignins were characterised using wet chemistry, spectroscopy and thermogravimetry analysis (TGA), and the results compared to soda lignin from NaOH pretreatment of bagasse. The IL and EG lignins contained no or trace amounts of carbohydrates, slightly lower hydrogen content but slightly higher oxygen contents than soda lignin. The IL and EG lignins contained more C-3 and C-5 reactive sites for Mannich reaction and had more p-hydroxypheny propane unit structures than soda lignin. Two-dimensional heteronuclear single quantum coherence (2D HSQC) nuclear magnetic resonance (NMR) identified the major substructural units in the lignins, and allowed differences among them to be studied. As EG lignins were extracted in very reactive environment, intermediate enol ethers were formed and led to cleavage reactions which were not apparent in the other lignins. 31 P NMR and infra-red spectroscopy results showed that IL and EG lignins had lower total hydroxyl content than soda lignin, probably indicating that a higher degree of self-polymerisation occurred during bagasse pretreatment, despite the use of lower temperature and shorter reaction time. On the basis of the salient features of these lignins, potential applications were proposed. - Highlights: • Lignins were recovered from ethylene glycol (EG) and ionic liquid (IL) processes. • IL and EG lignins contained no or trace amounts of carbohydrates. • IL and EG lignin had more C-3 and C-5 sites for Mannich reaction than soda

  4. Magnetic vortex state and multi-domain pattern in electrodeposited hemispherical nanogranular nickel films

    International Nuclear Information System (INIS)

    Samardak, Alexander; Sukovatitsina, Ekaterina; Ognev, Alexey; Stebliy, Maksim; Davydenko, Alexander; Chebotkevich, Ludmila; Keun Kim, Young; Nasirpouri, Forough; Janjan, Seyed-Mehdi; Nasirpouri, Farzad

    2014-01-01

    Magnetic states of nickel nanogranular films were studied in two distinct structures of individual and agglomerated granules electrodeposited on n-type Si(1 1 1) surface from a modified Watts bath at a low pH of 2. Magnetic force microscopy and micromagnetic simulations revealed three-dimensional out-of-plane magnetic vortex states in stand-alone hemispherical granules and their arrays, and multi-domain patterns in large agglomerates and integrated films. Once the granules coalesce into small chains or clusters, the coercivity values increased due to the reduction of inter-granular spacing and strengthening of the magnetostatic interaction. Further growth leads to the formation of a continuous granulated film which strongly affected the coercivity and remanence. This was characterized by the domain wall nucleation and propagation leading to a stripe domain pattern. Magnetoresistance measurements as a function of external magnetic field are indicative of anisotropic magnetoresistance (AMR) for the continuous films electrodeposited on Si substrate. - Highlights: • Magnetic states of electrodeposited nickel in isolated spherical and agglomerated nanogranules, and a continuous film. • Preferential magnetization reversal mechanism in isolated granules is vortex state. • Micromagnetic simulations confirm the three-dimensional vortex. • Transition between the vortex state and multi-domain magnetic pattern causes a significant decrease in the coercive force. • Continuous nickel films electrodeposited on silicon substrate exhibit AMR whose magnitude increases with the film thickness

  5. Degradation and depolymerization of plastic waste by local bacterial isolates and bubble column reactor

    Science.gov (United States)

    Hussein, Amal A.; Alzuhairi, Mohammed; Aljanabi, Noor H.

    2018-05-01

    Accumulation of plastics, especially Polyethylene terephthalate (PET), is an ever increasing ecological threat due to its excessive usage in everyday human life. Nowadays, there are many methods to get rid of plastic wastes including burning, recycling and burying. However, these methods are not very active since their long period, anaerobic conditions that increase the rate of toxic materials released into the environment. This work aims to study the biological degradation of PET microorganism isolated from soil sample. Thirty eight (38) bacterial isolates were isolated from ten soil and plastic waste sample collected from four different waste disposal sites in Baghdad city during different periods between December 2016 and March 2017. Isolation was performed using enrichment culture method (flasks method) by culturing the soil samples in flasks with MSM medium where there is no carbon source only PET. Results showed that Al-Za'farania sample gave a higher number of isolates (13 isolates), while other samples gave less number of isolates. Screening was performed depending on their ability to grow in liquid MSM which contains PET powder and pieces and change the color of the PET-emulsified liquid medium as well as their ability to form the clear zone on PET-MSM agar. The results showed that NH-D-1 isolate has the higher ability to degrade DPET and PET pieces. According to morphological, biochemical characterization and Vitek-2 technique, the most active isolate was identified as Acinetobacter baumannii.

  6. End States, Ladder Compounds, and Domain-Wall Fermions

    International Nuclear Information System (INIS)

    Creutz, M.

    1999-01-01

    A magnetic field applied to a cross-linked ladder compound can generate isolated electronic states bound to the ends of the chain. After exploring the interference phenomena responsible, I discuss a connection to the domain-wall approach to chiral fermions in lattice gauge theory. The robust nature of the states under small variations of the bond strengths is tied to chiral symmetry and the multiplicative renormalization of fermion masses. copyright 1999 The American Physical Society

  7. Non-dissipative energy capture of confined liquid in nanopores

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Baoxing; Chen, Xi [Columbia Nanomechanics Research Center, Department of Earth and Environmental Engineering, Columbia University, New York, New York 10027 (United States); Lu, Weiyi; Zhao, Cang [Department of Structural Engineering, University of California–San Diego, La Jolla, California 92093-0085 (United States); Qiao, Yu, E-mail: yqiao@ucsd.edu [Department of Structural Engineering, University of California–San Diego, La Jolla, California 92093-0085 (United States); Program of Materials Science and Engineering, University of California–San Diego, La Jolla, CA 92093 (United States)

    2014-05-19

    In the past, energy absorption of protection/damping materials is mainly based on energy dissipation, which causes a fundamental conflict between the requirements of safety/comfort and efficiency. In the current study, a nanofluidic “energy capture” system is reported, which is based on nanoporous materials and nonwetting liquid. Both molecular dynamics simulations and experiments show that as the liquid overcomes the capillary effect and infiltrates into the nanopores, the mechanical energy of a stress wave could be temporarily stored by the confined liquid phase and isolated from the wave energy transmission path. Such a system can work under a relatively low pressure for mitigating high-pressure stress waves, not necessarily involved in any energy dissipation processes.

  8. Non-dissipative energy capture of confined liquid in nanopores

    International Nuclear Information System (INIS)

    Xu, Baoxing; Chen, Xi; Lu, Weiyi; Zhao, Cang; Qiao, Yu

    2014-01-01

    In the past, energy absorption of protection/damping materials is mainly based on energy dissipation, which causes a fundamental conflict between the requirements of safety/comfort and efficiency. In the current study, a nanofluidic “energy capture” system is reported, which is based on nanoporous materials and nonwetting liquid. Both molecular dynamics simulations and experiments show that as the liquid overcomes the capillary effect and infiltrates into the nanopores, the mechanical energy of a stress wave could be temporarily stored by the confined liquid phase and isolated from the wave energy transmission path. Such a system can work under a relatively low pressure for mitigating high-pressure stress waves, not necessarily involved in any energy dissipation processes.

  9. Numerical modeling of ultrasonic cavitation in ionic liquids

    Science.gov (United States)

    Calvisi, Michael L.; Elder, Ross M.

    2017-11-01

    Ionic liquids have favorable properties for sonochemistry applications in which the high temperatures and pressures achieved by cavitation bubbles are important drivers of chemical processes. Two different numerical models are presented to simulate ultrasonic cavitation in ionic liquids, each with different capabilities and physical assumptions. A model based on a compressible form of the Rayleigh-Plesset equation (RPE) simulates ultrasonic cavitation of a spherical bubble with a homogeneous interior, incorporating evaporation and condensation at the bubble surface, and temperature-varying thermodynamic properties in the interior. A second, more computationally intensive model of a spherical bubble uses the finite element method (FEM) and accounts for spatial variations in pressure and temperature throughout the flow domain. This model provides insight into heat transfer across the bubble surface and throughout the bubble interior and exterior. Parametric studies are presented for sonochemistry applications involving ionic liquids as a solvent, examining a range of realistic ionic liquid properties and initial conditions to determine their effect on temperature and pressure. Results from the two models are presented for parametric variations including viscosity, thermal conductivity, water content of the ionic liquid solvent, acoustic frequency, and initial bubble pressure. An additional study performed with the FEM model examines thermal penetration into the surrounding ionic liquid during bubble oscillation. The results suggest the prospect of tuning ionic liquid properties for specific applications.

  10. Electrical detection of liquid lithium leaks from pipe joints

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, J. A., E-mail: jschwart@pppl.gov; Jaworski, M. A.; Mehl, J.; Kaita, R.; Mozulay, R. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543-0451 (United States)

    2014-11-15

    A test stand for flowing liquid lithium is under construction at Princeton Plasma Physics Laboratory. As liquid lithium reacts with atmospheric gases and water, an electrical interlock system for detecting leaks and safely shutting down the apparatus has been constructed. A defense in depth strategy is taken to minimize the risk and impact of potential leaks. Each demountable joint is diagnosed with a cylindrical copper shell electrically isolated from the loop. By monitoring the electrical resistance between the pipe and the copper shell, a leak of (conductive) liquid lithium can be detected. Any resistance of less than 2 kΩ trips a relay, shutting off power to the heaters and pump. The system has been successfully tested with liquid gallium as a surrogate liquid metal. The circuit features an extensible number of channels to allow for future expansion of the loop. To ease diagnosis of faults, the status of each channel is shown with an analog front panel LED, and monitored and logged digitally by LabVIEW.

  11. Numerical study of liquid crystal elastomers by a mixed finite element method

    KAUST Repository

    LUO, C.; CALDERER, M. C.

    2011-01-01

    Liquid crystal elastomers present features not found in ordinary elastic materials, such as semi-soft elasticity and the related stripe domain phenomenon. In this paper, the two-dimensional Bladon-Terentjev-Warner model and the one-constant Oseen

  12. Beyond cross-domain learning: Multiple-domain nonnegative matrix factorization

    KAUST Repository

    Wang, Jim Jing-Yan; Gao, Xin

    2014-01-01

    Traditional cross-domain learning methods transfer learning from a source domain to a target domain. In this paper, we propose the multiple-domain learning problem for several equally treated domains. The multiple-domain learning problem assumes that samples from different domains have different distributions, but share the same feature and class label spaces. Each domain could be a target domain, while also be a source domain for other domains. A novel multiple-domain representation method is proposed for the multiple-domain learning problem. This method is based on nonnegative matrix factorization (NMF), and tries to learn a basis matrix and coding vectors for samples, so that the domain distribution mismatch among different domains will be reduced under an extended variation of the maximum mean discrepancy (MMD) criterion. The novel algorithm - multiple-domain NMF (MDNMF) - was evaluated on two challenging multiple-domain learning problems - multiple user spam email detection and multiple-domain glioma diagnosis. The effectiveness of the proposed algorithm is experimentally verified. © 2013 Elsevier Ltd. All rights reserved.

  13. Beyond cross-domain learning: Multiple-domain nonnegative matrix factorization

    KAUST Repository

    Wang, Jim Jing-Yan

    2014-02-01

    Traditional cross-domain learning methods transfer learning from a source domain to a target domain. In this paper, we propose the multiple-domain learning problem for several equally treated domains. The multiple-domain learning problem assumes that samples from different domains have different distributions, but share the same feature and class label spaces. Each domain could be a target domain, while also be a source domain for other domains. A novel multiple-domain representation method is proposed for the multiple-domain learning problem. This method is based on nonnegative matrix factorization (NMF), and tries to learn a basis matrix and coding vectors for samples, so that the domain distribution mismatch among different domains will be reduced under an extended variation of the maximum mean discrepancy (MMD) criterion. The novel algorithm - multiple-domain NMF (MDNMF) - was evaluated on two challenging multiple-domain learning problems - multiple user spam email detection and multiple-domain glioma diagnosis. The effectiveness of the proposed algorithm is experimentally verified. © 2013 Elsevier Ltd. All rights reserved.

  14. Aggression and Moral Development: Integrating Social Information Processing and Moral Domain Models

    Science.gov (United States)

    Arsenio, William F.; Lemerise, Elizabeth A.

    2004-01-01

    Social information processing and moral domain theories have developed in relative isolation from each other despite their common focus on intentional harm and victimization, and mutual emphasis on social cognitive processes in explaining aggressive, morally relevant behaviors. This article presents a selective summary of these literatures with…

  15. Investigation of bubble flow regimes in nucleate boiling of highly-wetting liquids

    International Nuclear Information System (INIS)

    Tong, W.; Bar-Cohen, A.; Simon, T.W.

    1991-01-01

    This paper describes an investigation of the bubble flow regimes in nucleate boiling of FC-72, a highly-wetting liquid. Theoretically analysis of vapor bubble generation and departure from the heated surface reveals that the heat fluxes required for the merging of consecutive bubbles, for highly-wetting liquids, lie in the upper range of the nucleate boiling heat flux. A visual and photographic study of nucleate boiling from sputtered platinum surfaces has supported the theoretical results and shown that the isolated bubble behavior extends to at least 50-80% of the critical heat flux, considerably higher than observed by others with water. Lateral coalescence of adjacent bubbles has been found to be a more likely cause of the termination of the isolated bubble regime. These findings suggest that thermal transport models which are based on isolated bubble behavior may be applicable to nearly the entire range of nucleate boiling of electronic cooling fluids

  16. Salmonella in Liquid Eggs and Other Foods in Fukuoka Prefecture, Japan

    Directory of Open Access Journals (Sweden)

    Koichi Murakami

    2013-01-01

    Full Text Available The study aimed to evaluate the prevalence of Salmonella in retail and wholesale foods in Fukuoka Prefecture, Japan. A total of 2,021 samples collected between 1999 and 2010 were tested using a culture method. Samples consisted of liquid eggs (n=30, meat (beef and pork (n=781, offal (n=69, processed meats (n=2, seafood (n=232, processed seafood (dried fish (n=76, vegetables (n=481, processed vegetables (n=87, fruits (n=167, and herbs (n=96 from 574 outlets and wholesale agents in 15 areas (five samples were undocumented regarding outlets. Overall, liquid egg showed significantly (P<0.001 higher frequencies of Salmonella contamination (13.3% than beef (1/423, 0.2% and pork (3/235, 1.3%. Salmonella enterica subsp. enterica serovar Enteritidis, the most common serovar as a human pathogen, were isolated from two liquid egg samples. No Salmonella were isolated from seafood and vegetable-related samples including seed sprouts (n=261. In conclusion, liquid egg is a significant Salmonella vehicle, showing a need to continue the vaccination of chickens to prevent S. Enteritidis contamination in Japanese eggs. Moreover, further study is needed to evaluate Salmonella contamination in seed sprouts with more sampling from retailers there.

  17. Salmonella in liquid eggs and other foods in fukuoka prefecture, Japan.

    Science.gov (United States)

    Murakami, Koichi; Noda, Tamie; Onozuka, Daisuke; Sera, Nobuyuki

    2013-01-01

    The study aimed to evaluate the prevalence of Salmonella in retail and wholesale foods in Fukuoka Prefecture, Japan. A total of 2,021 samples collected between 1999 and 2010 were tested using a culture method. Samples consisted of liquid eggs (n = 30), meat (beef and pork) (n = 781), offal (n = 69), processed meats (n = 2), seafood (n = 232), processed seafood (dried fish) (n = 76), vegetables (n = 481), processed vegetables (n = 87), fruits (n = 167), and herbs (n = 96) from 574 outlets and wholesale agents in 15 areas (five samples were undocumented regarding outlets). Overall, liquid egg showed significantly (P < 0.001) higher frequencies of Salmonella contamination (13.3%) than beef (1/423, 0.2%) and pork (3/235, 1.3%). Salmonella enterica subsp. enterica serovar Enteritidis, the most common serovar as a human pathogen, were isolated from two liquid egg samples. No Salmonella were isolated from seafood and vegetable-related samples including seed sprouts (n = 261). In conclusion, liquid egg is a significant Salmonella vehicle, showing a need to continue the vaccination of chickens to prevent S. Enteritidis contamination in Japanese eggs. Moreover, further study is needed to evaluate Salmonella contamination in seed sprouts with more sampling from retailers there.

  18. The Epidemiology of Social Isolation: National Health & Aging Trends Study.

    Science.gov (United States)

    Cudjoe, Thomas K M; Roth, David L; Szanton, Sarah L; Wolff, Jennifer L; Boyd, Cynthia M; Thorpe, Roland J

    2018-03-26

    Social isolation among older adults is an important but under-recognized risk for poor health outcomes. Methods are needed to identify subgroups of older adults at risk for social isolation. We constructed a typology of social isolation using data from the National Health and Aging Trends Study (NHATS) and estimated the prevalence and correlates of social isolation among community-dwelling older adults. The typology was formed from four domains: living arrangement, core discussion network size, religious attendance, and social participation. In 2011, 24% of self-responding, community-dwelling older adults (65+ years), approximately 7.7 million people, were characterized as socially isolated, including 1.3 million (4%) who were characterized as severely socially isolated. Multinomial multivariable logistic regression indicated that being unmarried, male, having low education, and low income were all independently associated with social isolation. Black and Hispanic older adults had lower odds of social isolation compared to White older adults, after adjusting for covariates. Social isolation is an important and potentially modifiable risk that affects a significant proportion of the older adult population.

  19. Metrology for terahertz time-domain spectrometers

    Science.gov (United States)

    Molloy, John F.; Naftaly, Mira

    2015-12-01

    In recent years the terahertz time-domain spectrometer (THz TDS) [1] has emerged as a key measurement device for spectroscopic investigations in the frequency range of 0.1-5 THz. To date, almost every type of material has been studied using THz TDS, including semiconductors, ceramics, polymers, metal films, liquid crystals, glasses, pharmaceuticals, DNA molecules, proteins, gases, composites, foams, oils, and many others. Measurements with a TDS are made in the time domain; conversion from the time domain data to a frequency spectrum is achieved by applying the Fourier Transform, calculated numerically using the Fast Fourier Transform (FFT) algorithm. As in many other types of spectrometer, THz TDS requires that the sample data be referenced to similarly acquired data with no sample present. Unlike frequency-domain spectrometers which detect light intensity and measure absorption spectra, a TDS records both amplitude and phase information, and therefore yields both the absorption coefficient and the refractive index of the sample material. The analysis of the data from THz TDS relies on the assumptions that: a) the frequency scale is accurate; b) the measurement of THz field amplitude is linear; and c) that the presence of the sample does not affect the performance characteristics of the instrument. The frequency scale of a THz TDS is derived from the displacement of the delay line; via FFT, positioning errors may give rise to frequency errors that are difficult to quantify. The measurement of the field amplitude in a THz TDS is required to be linear with a dynamic range of the order of 10 000. And attention must be given to the sample positioning and handling in order to avoid sample-related errors.

  20. Local layer structure of smectic liquid crystals by X-ray micro-diffraction

    CERN Document Server

    Takanishi, Y

    2003-01-01

    The local layer structure of smectic liquid crystal has been measured using time-resolved synchrotron X-ray micro-diffraction. Typical layer disorders observed in surface stabilized (anti-) ferroelectric liquid crystals, i.e. a stripe texture, a needed-like defect and a zigzag defect, are directly analyzed. The detailed analysis slows that the surface anchoring force due to the interaction between the liquid crystal molecule and the alignment thin film plays an important role to realize both the static and dynamic local layer structures. The layer structure of the circular domain observed in the liquid crystal of bent-shaped molecules found to depend on the applied electric field though the optical micrograph shows little difference. The frustrated, double and single layer structures of the bent-shaped molecule liquid crystal are determined depending on the terminal alkyl chain length. (author)

  1. Directed self-assembly of liquid crystalline blue-phases into ideal single-crystals

    Science.gov (United States)

    Martínez-González, Jose A.; Li, Xiao; Sadati, Monirosadat; Zhou, Ye; Zhang, Rui; Nealey, Paul F.; de Pablo, Juan J.

    2017-06-01

    Chiral nematic liquid crystals are known to form blue phases--liquid states of matter that exhibit ordered cubic arrangements of topological defects. Blue-phase specimens, however, are generally polycrystalline, consisting of randomly oriented domains that limit their performance in applications. A strategy that relies on nano-patterned substrates is presented here for preparation of stable, macroscopic single-crystal blue-phase materials. Different template designs are conceived to exert control over different planes of the blue-phase lattice orientation with respect to the underlying substrate. Experiments are then used to demonstrate that it is indeed possible to create stable single-crystal blue-phase domains with the desired orientation over large regions. These results provide a potential avenue to fully exploit the electro-optical properties of blue phases, which have been hindered by the existence of grain boundaries.

  2. Development and assessment of closure technology for liquid-waste disposal sites

    International Nuclear Information System (INIS)

    Phillips, S.J.; Relyea, J.F.; Seitz, R.R.; Cammann, J.W.

    1990-01-01

    Discharge of low-level liquid wastes into soils was practiced previously at the Hanford Site. Technologies for long-term confinement of subsurface contaminants are needed. Additionally, methods are needed to assess the effectiveness of confinement technologies in remediating potentially diverse environmental conditions. Recently developed site remediation systems and assessment methods for in situ stabilization and isolation of radioactive and other contaminants within and below low-level liquid-waste disposal structures are summarized

  3. On the edge of habitability and the extremes of liquidity

    Science.gov (United States)

    Hansen-Goos, Hendrik; Thomson, Erik S.; Wettlaufer, J. S.

    2014-08-01

    The physical and biological mechanisms that extend the equilibrium domain of liquid water into the ice region of the bulk phase diagram are examined in view of their importance for the enhancement of planetary habitability. The physical phenomena studied are the premelting of ice, which allows for films of liquid water at temperatures well below freezing, and the wetting of hygroscopic salts with the persistence of briny films even for thermodynamic conditions remote from those of bulk liquid water. Organisms are known to produce a variety of frost-suppressing substances, one of which, the anti-freeze protein, is described here. In this article, we provide a synthesis of theoretical and experimental studies whilst extending ideas into new territory as we address the question of habitability.

  4. Systems and methods for enhancing isolation of high-temperature reactor containments

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, Per F.

    2017-09-26

    A high-temperature containment-isolation system for transferring heat from a nuclear reactor containment to a high-pressure heat exchanger is presented. The system uses a high-temperature, low-volatility liquid coolant such as a molten salt or a liquid metal, where the coolant flow path provides liquid free surfaces a short distance from the containment penetrations for the reactor hot-leg and the cold-leg, where these liquid free surfaces have a cover gas maintained at a nearly constant pressure and thus prevent high-pressures from being transmitted into the reactor containment, and where the reactor vessel is suspended within a reactor cavity with a plurality of refractory insulator blocks disposed between an actively cooled inner cavity liner and the reactor vessel.

  5. Protein sorting by lipid phase-like domains supports emergent signaling function in B lymphocyte plasma membranes.

    Science.gov (United States)

    Stone, Matthew B; Shelby, Sarah A; Núñez, Marcos F; Wisser, Kathleen; Veatch, Sarah L

    2017-02-01

    Diverse cellular signaling events, including B cell receptor (BCR) activation, are hypothesized to be facilitated by domains enriched in specific plasma membrane lipids and proteins that resemble liquid-ordered phase-separated domains in model membranes. This concept remains controversial and lacks direct experimental support in intact cells. Here, we visualize ordered and disordered domains in mouse B lymphoma cell membranes using super-resolution fluorescence localization microscopy, demonstrate that clustered BCR resides within ordered phase-like domains capable of sorting key regulators of BCR activation, and present a minimal, predictive model where clustering receptors leads to their collective activation by stabilizing an extended ordered domain. These results provide evidence for the role of membrane domains in BCR signaling and a plausible mechanism of BCR activation via receptor clustering that could be generalized to other signaling pathways. Overall, these studies demonstrate that lipid mediated forces can bias biochemical networks in ways that broadly impact signal transduction.

  6. Phosphorylation of both nucleoplasmin domains is required for activation of its chromatin decondensation activity

    DEFF Research Database (Denmark)

    Bañuelos, Sonia; Omaetxebarria, Miren J; Ramos, Isbaal

    2007-01-01

    Nucleoplasmin (NP) is a histone chaperone involved in nucleosome assembly, chromatin decondensation at fertilization, and apoptosis. To carry out these activities NP has to interact with different types of histones, an interaction that is regulated by phosphorylation. Here we have identified...... are found at the tail domain, flanking the nuclear localization signal. Phosphorylation-mimicking mutations render a recombinant protein as active in chromatin decondensation as hyperphosphorylated NP isolated from Xenopus laevis eggs. Comparison of mutants in which the core and tail domains of the protein...... were independently or simultaneously "activated" indicates that activation or phosphorylation of both protein domains is required for NP to efficiently extract linker-type histones from chromatin....

  7. Visualization of residual organic liquid trapped in aquifers

    International Nuclear Information System (INIS)

    Conrad, S.H.; Wilson, J.L.; Mason, W.R.; Peplinski, W.J.

    1992-01-01

    Organic liquids that are essentially immiscible with water migrate through the subsurface under the influence of capillary, viscous, and buoyancy forces. These liquids originate from the improper disposal of hazardous wastes, and the spills and leaks of petroleum hydrocarbons and solvents. The flow visualization experiments described in this study examined the migration of organic liquids through the saturated zone of aquifers, with a primary focus on the behavior of the residual organic liquid saturation, referring to that portion of the organic liquid that is trapped by capillary forces. Etched glass micromodels were used to visually observe dynamic multiphase displacement processes in pore networks. The resulting fluid distributions were photographed. Pore and blob casts were produced by a technique in which an organic liquid was solidified in place within a sand column at the conclusion of a displacement. The columns were sectioned and examined under optical and scanning electron microscopes. Photomicrographs of these sections show the morphology of the organic phase and its location within the sand matrix. The photographs from both experimental techniques reveal that in the saturated zone large amounts of residual organic liquid are trapped as isolated blobs of microscopic size. The size, shape, and spatial distribution of these blobs of residual organic liquid affect the dissolution of organic liquid into the water phase and the biotransformation of organic components. These processes are of concern for the prediction of pollution migration and the design of aquifer remediation schemes

  8. Production and novel quantification of haemolysins produced by coagulase-negative staphylococci isolated from subclinical mastitis in sheep.

    Science.gov (United States)

    Kanellos, T S; Burriel, A R

    2002-07-01

    Coagulase-negative staphylococci producing cell-damaging toxins were isolated from the milk of sheep with subclinical mastitis. The haemolytic activity of Coagulase-negative staphylococcal strains was assessed on solid and liquid culture media. More than 61% and 76% of the tested strains on solid media produced evidence of alpha- and delta- haemolysins and more than 78% produced synergistic haemolysis. However almost all isolates producing haemolysin in liquid culture media produced only very few units of haemolysin compared to the positive control of five Coagulase-positive strains of staphylococci. It was concluded that solid media are better for classifying Coagulase-negative staphylococci as producers or not of haemolysins, and liquid media for measuring the size of this activity within the first few hours of intramammary infection.

  9. Identifying APT Malware Domain Based on Mobile DNS Logging

    Directory of Open Access Journals (Sweden)

    Weina Niu

    2017-01-01

    Full Text Available Advanced Persistent Threat (APT is a serious threat against sensitive information. Current detection approaches are time-consuming since they detect APT attack by in-depth analysis of massive amounts of data after data breaches. Specifically, APT attackers make use of DNS to locate their command and control (C&C servers and victims’ machines. In this paper, we propose an efficient approach to detect APT malware C&C domain with high accuracy by analyzing DNS logs. We first extract 15 features from DNS logs of mobile devices. According to Alexa ranking and the VirusTotal’s judgement result, we give each domain a score. Then, we select the most normal domains by the score metric. Finally, we utilize our anomaly detection algorithm, called Global Abnormal Forest (GAF, to identify malware C&C domains. We conduct a performance analysis to demonstrate that our approach is more efficient than other existing works in terms of calculation efficiency and recognition accuracy. Compared with Local Outlier Factor (LOF, k-Nearest Neighbor (KNN, and Isolation Forest (iForest, our approach obtains more than 99% F-M and R for the detection of C&C domains. Our approach not only can reduce data volume that needs to be recorded and analyzed but also can be applicable to unsupervised learning.

  10. Comparison of alignment tensors generated for native tRNAVal using magnetic fields and liquid crystalline media

    International Nuclear Information System (INIS)

    Latham, Michael P.; Hanson, Paul; Brown, Darin J.; Pardi, Arthur

    2008-01-01

    Residual dipolar couplings (RDCs) complement standard NOE distance and J-coupling torsion angle data to improve the local and global structure of biomolecules in solution. One powerful application of RDCs is for domain orientation studies, which are especially valuable for structural studies of nucleic acids, where the local structure of a double helix is readily modeled and the orientations of the helical domains can then be determined from RDC data. However, RDCs obtained from only one alignment media generally result in degenerate solutions for the orientation of multiple domains. In protein systems, different alignment media are typically used to eliminate this orientational degeneracy, where the combination of RDCs from two (or more) independent alignment tensors can be used to overcome this degeneracy. It is demonstrated here for native E. coli tRNA Val that many of the commonly used liquid crystalline alignment media result in very similar alignment tensors, which do not eliminate the 4-fold degeneracy for orienting the two helical domains in tRNA. The intrinsic magnetic susceptibility anisotropy (MSA) of the nucleobases in tRNA Val was also used to obtain RDCs for magnetic alignment at 800 and 900 MHz. While these RDCs yield a different alignment tensor, the specific orientation of this tensor combined with the high rhombicity for the tensors in the liquid crystalline media only eliminates two of the four degenerate orientations for tRNA Val . Simulations are used to show that, in optimal cases, the combination of RDCs obtained from liquid crystalline medium and MSA-induced alignment can be used to obtain a unique orientation for the two helical domains in tRNA Val

  11. Domains and domain loss

    DEFF Research Database (Denmark)

    Haberland, Hartmut

    2005-01-01

    politicians and in the media, especially in the discussion whether some languages undergo ‘domain loss’ vis-à-vis powerful international languages like English. An objection that has been raised here is that domains, as originally conceived, are parameters of language choice and not properties of languages...

  12. Improving the performance of DomainDiscovery of protein domain boundary assignment using inter-domain linker index

    Directory of Open Access Journals (Sweden)

    Zomaya Albert Y

    2006-12-01

    Full Text Available Abstract Background Knowledge of protein domain boundaries is critical for the characterisation and understanding of protein function. The ability to identify domains without the knowledge of the structure – by using sequence information only – is an essential step in many types of protein analyses. In this present study, we demonstrate that the performance of DomainDiscovery is improved significantly by including the inter-domain linker index value for domain identification from sequence-based information. Improved DomainDiscovery uses a Support Vector Machine (SVM approach and a unique training dataset built on the principle of consensus among experts in defining domains in protein structure. The SVM was trained using a PSSM (Position Specific Scoring Matrix, secondary structure, solvent accessibility information and inter-domain linker index to detect possible domain boundaries for a target sequence. Results Improved DomainDiscovery is compared with other methods by benchmarking against a structurally non-redundant dataset and also CASP5 targets. Improved DomainDiscovery achieves 70% accuracy for domain boundary identification in multi-domains proteins. Conclusion Improved DomainDiscovery compares favourably to the performance of other methods and excels in the identification of domain boundaries for multi-domain proteins as a result of introducing support vector machine with benchmark_2 dataset.

  13. Active structuring of colloidal armour on liquid drops

    Science.gov (United States)

    Dommersnes, Paul; Rozynek, Zbigniew; Mikkelsen, Alexander; Castberg, Rene; Kjerstad, Knut; Hersvik, Kjetil; Otto Fossum, Jon

    2013-06-01

    Adsorption and assembly of colloidal particles at the surface of liquid droplets are at the base of particle-stabilized emulsions and templating. Here we report that electrohydrodynamic and electro-rheological effects in leaky-dielectric liquid drops can be used to structure and dynamically control colloidal particle assemblies at drop surfaces, including electric-field-assisted convective assembly of jammed colloidal ‘ribbons’, electro-rheological colloidal chains confined to a two-dimensional surface and spinning colloidal domains on that surface. In addition, we demonstrate the size control of ‘pupil’-like openings in colloidal shells. We anticipate that electric field manipulation of colloids in leaky dielectrics can lead to new routes of colloidosome assembly and design for ‘smart armoured’ droplets.

  14. Soft Elasticity in Main Chain Liquid Crystal Elastomers

    Directory of Open Access Journals (Sweden)

    Anselm C. Griffin

    2013-06-01

    Full Text Available Main chain liquid crystal elastomers exhibit several interesting phenomena, such as three different regimes of elastic response, unconventional stress-strain relationship in one of these regimes, and the shape memory effect. Investigations are beginning to reveal relationships between their macroscopic behavior and the nature of domain structure, microscopic smectic phase structure, relaxation mechanism, and sample history. These aspects of liquid crystal elastomers are briefly reviewed followed by a summary of the results of recent elastic and high-resolution X-ray diffraction studies of the shape memory effect and the dynamics of the formation of the smectic-C chevron-like layer structure. A possible route to realizing auxetic effect at molecular level is also discussed.

  15. Lactic acid bacteria as functional probiotic isolates for inhibiting the growth of Aspergillus flavus, A. parasiticus, A. niger and Penicillium chrysogenum.

    Science.gov (United States)

    Abbaszadeh, S; Tavakoli, R; Sharifzadeh, A; Shokri, H

    2015-12-01

    The aim of this study was to assess the potential of lactic acid bacteria (LAB) such as Lactobacillus acidophilus, L. rhamnosus, L. casei, L. paracasei and Bifidobacterium bifidum to inhibit the outgrowth of some common food-spoiling fungi including Aspergillus niger, A. flavus, A. parasiticus and Penicillium chrysogenum. Bacterial isolates were cultured on Mann Rogosa Sharpe (MRS) broth and liquid cultures and supernatants were prepared. The antifungal activity was tested using the agar well diffusion method. Both liquid culture and supernatant of L. casei isolate exhibited high antifungal activity, followed by L. acidophilus and L. paracasei isolates. The least activity was recorded for the isolates B. bifidum, while the isolate L. rhamnosus was moderately active against tested fungi. The antifungal activity of the supernatants obtained from all probiotic isolates against fungi was significantly less than that of liquid cultures (Pniger and A. parasiticus. These results suggest that probiotic bacteria strains have the ability to prevent the growth of pathogenic and mycotoxigenic fungi as antifungal agents for various biomedical applications. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  16. Isolation and biological activity of frankiamide.

    Science.gov (United States)

    Haansuu, J P; Klika, K D; Söderholm, P P; Ovcharenko, V V; Pihlaja, K; Haahtela, K K; Vuorela, P M

    2001-07-01

    An antibiotic produced by the symbiotic actinomycete Frankia strain AiPs1 was isolated from culture broth using optimized thin-layer chromatography and high-performance liquid chromatography (HPLC) methods. The novel compound that was isolated, dubbed frankiamide, displayed antimicrobial activity against all 14 Gram-positive bacterial strains and six pathogenic fungal strains tested. The pathogenic actinomycete Clavibacter michiganensis and the oomycete Phytophthora were especially susceptible. In addition to displaying antimicrobial activity, frankiamide also strongly inhibited 45Ca(2+) fluxes in clonal rat pituitary GH4C1 tumor cells and was comparable to a frequently used calcium antagonist, verapamil hydrochloride. The results of HPLC analysis, supported by both nuclear magnetic resonance and mass spectroscopy studies, showed that frankiamide has a high affinity for Na(+) ions.

  17. Liquidity Determinants of the Selected Banking Sectors and their Size Groups

    Directory of Open Access Journals (Sweden)

    Jana Laštůvková

    2016-01-01

    Full Text Available The article focuses on the factors affecting the liquidity of selected bank sectors, as well as their size groups, using panel regression analysis. For higher complexity of the results, multiple dependent variables are used: liquidity creation, outflow and net change. The values are calculated based on the specific method of liquidity risk measurement – gross liquidity flows. The results indicate both multiple effects of some factors on the given variables, as well as isolated influence of factors on a single liquidity form or size group. Thus, when looking for determinants using just one form of liquidity, such as creation, the results need not necessarily comprehensively show the influence of the given factors, and can lead to erroneous conclusions. The results also point to the differing behaviours of the size groups and their different sensitivity on the factors; smaller banks have shown higher sensitivity on macroeconomic variables. Higher flexibility in regulation could lead to higher optimization.

  18. Isolation and Characterization of Seed-Borne Pathogenic Bacteria

    African Journals Online (AJOL)

    76 L.K. Ashura et aI. Table 4: Selected morphological and biochemical characteristics of bacteria isolates from rice seed as de- tected by the Liquid Assay on mXOS. Ace. No.1. Fluorescentl. Kovac's. OIF. NR. GL. SH. LS. HR. Pstho. Diolog Identification lsolale(s). Colour of·. Oxidase. TIP g on. (Similarity). I. Pigment. Rice.

  19. Isolation of fucoxanthin and fatty acids analysis of Padina australis ...

    African Journals Online (AJOL)

    Fucoxanthin has been successfully isolated from species of Malaysian brown seaweed, namely Padina australis. The purity of the fucoxanthin is >98% as indicated by high performance liquid chromatography analysis. This seaweed also contains a considerable amount of unsaturated fatty acids. Thirteen fatty acids were ...

  20. Specificity and autoregulation of Notch binding by tandem WW domains in suppressor of Deltex.

    Science.gov (United States)

    Jennings, Martin D; Blankley, Richard T; Baron, Martin; Golovanov, Alexander P; Avis, Johanna M

    2007-09-28

    WW domains target proline-tyrosine (PY) motifs and frequently function as tandem pairs. When studied in isolation, single WW domains are notably promiscuous and regulatory mechanisms are undoubtedly required to ensure selective interactions. Here, we show that the fourth WW domain (WW4) of Suppressor of Deltex, a modular Nedd4-like protein that down-regulates the Notch receptor, is the primary mediator of a direct interaction with a Notch-PY motif. A natural Trp to Phe substitution in WW4 reduces its affinity for general PY sequences and enhances selective interaction with the Notch-PY motif via compensatory specificity-determining interactions with PY-flanking residues. When WW4 is paired with WW3, domain-domain association, impeding proper folding, competes with Notch-PY binding to WW4. This novel mode of autoinhibition is relieved by binding of another ligand to WW3. Such cooperativity may facilitate the transient regulatory interactions observed in vivo between Su(dx) and Notch in the endocytic pathway. The highly conserved tandem arrangement of WW domains in Nedd4 proteins, and similar arrangements in more diverse proteins, suggests domain-domain communication may be integral to regulation of their associated cellular activities.

  1. [Amylase production by Aureobasidium pullulans in liquid and solid media].

    Science.gov (United States)

    Lodato, P B; Forchiassin, F; Segovia de Huergo, M B

    1997-01-01

    Amylase production by a strain of Aureobasidium pullulans isolated in the laboratory was evaluated in liquid media (complex and synthetic) and in solid medium (wheat bran). There was an inhibitory effect in amylase production or amylase secretion by glucose. Asparagine was the best nitrogen source for amylase production (4-6 g/l). Only chlamidospores and melanin but not, amylase activity, were obtained with ammonium sulfate. Amylase production in solid culture was higher than the production obtained in the liquid media assayed. Optimum initial moisture content in solid culture ranged between 57 and 74%. No difference was observed in amylase production between solid media inoculated with cells grown in liquid or solid media.

  2. Phase behaviour of macromolecular liquid crystalline materials. Computational studies at the molecular level

    International Nuclear Information System (INIS)

    Stimson, Lorna M.

    2003-01-01

    Molecular simulations provide an increasingly useful insight into the static and dynamic characteristics of materials. In this thesis molecular simulations of macro-molecular liquid crystalline materials are reported. The first liquid crystalline material that has been investigated is a side chain liquid crystal polymer (SCLCP). In this study semi-atomistic molecular dynamics simulations have been conducted at a range of temperatures and an aligning potential has been applied to mimic the effect of a magnetic field. In cooling the SCLCP from an isotropic melt, microphase separation was observed yielding a domain structure. The application of a magnetic field to this structure aligns the domains producing a stable smectic mesophase. This is the first study in which mesophases have been observed using an off-lattice model of a SCLCP. The second material that has been investigated is a dendrimer with terminal mesogenic functionalization. Here, a multi-scale approach has been taken with Monte Carlo studies of a single dendrimer molecule in the gas phase at the atomistic level, semi-atomistic molecular dynamics of a single molecule in liquid crystalline solvents and a coarse-grained molecular dynamics study of the dendrimer in the bulk. The coarse-grained model has been developed and parameterized using the results of the atomistic and semi-atomistic work. The single molecule studies showed that the liquid crystalline dendrimer was able to change its structure by conformational changes in the flexible chains that link the mesogenic groups to the core. Structural change was seen under the application of a mean field ordering potential in the gas phase, and in the presence of liquid crystalline solvents. No liquid crystalline phases were observed for the bulk phase studies of the coarse-grained model. However, when the length of the mesogenic units was increased there was some evidence for microphase separation in these systems. (author)

  3. Leaf storage conditions and genomic DNA isolation efficiency in ...

    African Journals Online (AJOL)

    SERVER

    2008-03-04

    Mar 4, 2008 ... Full Length Research Paper. Leaf storage ... 2006; Chen and Yang, 2004; Nan et al., 2003; Ipek and. Madison, 2001 ... the same function of pure DNA isolation. These are .... eppendorf tube and then dropped in liquid nitrogen for 2 min. The weighed ..... the solubility of polysaccharides in ethanol, effectively.

  4. Fully-automated in-syringe dispersive liquid-liquid microextraction for the determination of caffeine in coffee beverages.

    Science.gov (United States)

    Frizzarin, Rejane M; Maya, Fernando; Estela, José M; Cerdà, Víctor

    2016-12-01

    A novel fully-automated magnetic stirring-assisted lab-in-syringe analytical procedure has been developed for the fast and efficient dispersive liquid-liquid microextraction (DLLME) of caffeine in coffee beverages. The procedure is based on the microextraction of caffeine with a minute amount of dichloromethane, isolating caffeine from the sample matrix with no further sample pretreatment. Selection of the relevant extraction parameters such as the dispersive solvent, proportion of aqueous/organic phase, pH and flow rates have been carefully evaluated. Caffeine quantification was linear from 2 to 75mgL(-1), with detection and quantification limits of 0.46mgL(-1) and 1.54mgL(-1), respectively. A coefficient of variation (n=8; 5mgL(-1)) of a 2.1% and a sampling rate of 16h(-1), were obtained. The procedure was satisfactorily applied to the determination of caffeine in brewed, instant and decaf coffee samples, being the results for the sample analysis validated using high-performance liquid chromatography. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Liquid-metal dip seal with pneumatic spring

    International Nuclear Information System (INIS)

    Poindexter, A.M.

    1977-01-01

    An improved liquid-metal dip seal for sealing the annulus between rotating plugs in the reactor vessel head of a liquid-metal fast-breeder nuclear reactor has two legs of differing widths communicating under a seal blade; the wide leg is also in communication with cover gas of the reactor and the narrow leg is also in communication with an isolated plug annulus above the seal. The annulus contains inert gas which acts as a pneumatic spring. Upon increasing cover gas pressure which depresses the level in the wide leg and greatly increases the level in the narrow leg, the pneumatic spring is compressed, and resists further level changes, thus preventing radioactive cover gas from bubbling through the seal

  6. Drop Dynamics and Speciation in Isolation of Metals from Liquid Wastes by Reactive Scavenging

    Energy Technology Data Exchange (ETDEWEB)

    Arne J. Pearlstein; Alexander Scheeline

    2002-08-30

    Computational and experimental studies of the motion and dynamics of liquid drops in gas flows were conducted with relevance to reactive scavenging of metals from atomized liquid waste. Navier-Stoke's computations of deformable drops revealed a range of conditions from which prolate drops are expected, and showed how frajectiones of deformable drops undergoing deceleration can be computed. Experimental work focused on development of emission fluorescence, and scattering diagnostics. The instrument developed was used to image drop shapes, soot, and nonaxisymmetric departures from steady flow in a 22kw combustor

  7. LIQUID-LIQUID EXTRACTION COLUMNS

    Science.gov (United States)

    Thornton, J.D.

    1957-12-31

    This patent relates to liquid-liquid extraction columns having a means for pulsing the liquid in the column to give it an oscillatory up and down movement, and consists of a packed column, an inlet pipe for the dispersed liquid phase and an outlet pipe for the continuous liquid phase located in the direct communication with the liquid in the lower part of said column, an inlet pipe for the continuous liquid phase and an outlet pipe for the dispersed liquid phase located in direct communication with the liquid in the upper part of said column, a tube having one end communicating with liquid in the lower part of said column and having its upper end located above the level of said outlet pipe for the dispersed phase, and a piston and cylinder connected to the upper end of said tube for applying a pulsating pneumatic pressure to the surface of the liquid in said tube so that said surface rises and falls in said tube.

  8. Bis-sulfonic Acid Ionic Liquids for the Conversion of Fructose to 5-Hydroxymethyl-2-furfural

    Directory of Open Access Journals (Sweden)

    Sangho Koo

    2012-10-01

    Full Text Available Homogenous bis-sulfonic acid ionic liquids (1 mol equiv. in DMSO (10 mol equiv. at 100 °C efficiently mediated the conversion of D-fructose into 5-hydroxymethyl-2-furfural in 75% isolated yield, which was roughly a 10% increment compared to the case of the mono-sulfonic acid ionic liquids.

  9. Shark Variable New Antigen Receptor (VNAR Single Domain Antibody Fragments: Stability and Diagnostic Applications

    Directory of Open Access Journals (Sweden)

    Stewart Nuttall

    2013-01-01

    Full Text Available The single variable new antigen receptor domain antibody fragments (VNARs derived from shark immunoglobulin new antigen receptor antibodies (IgNARs represent some of the smallest known immunoglobulin-based protein scaffolds. As single domains, they demonstrate favorable size and cryptic epitope recognition properties, making them attractive in diagnosis and therapy of numerous disease states. Here, we examine the stability of VNAR domains with a focus on a family of VNARs specific for apical membrane antigen 1 (AMA-1 from Plasmodium falciparum. The VNARs are compared to traditional monoclonal antibodies (mAbs in liquid, lyophilized and immobilized nitrocellulose formats. When maintained in various formats at 45 °C, VNARs have improved stability compared to mAbs for periods of up to four weeks. Using circular dichroism spectroscopy we demonstrate that VNAR domains are able to refold following heating to 80 °C. We also demonstrate that VNAR domains are stable during incubation under potential in vivo conditions such as stomach acid, but not to the protease rich environment of murine stomach scrapings. Taken together, our results demonstrate the suitability of shark VNAR domains for various diagnostic platforms and related applications.

  10. Isolation of Biosurfactant Producing Bacteria from Oil Reservoirs

    Directory of Open Access Journals (Sweden)

    A Tabatabaee, M Mazaheri Assadi, AA Noohi,VA Sajadian

    2005-01-01

    Full Text Available Biosurfactants or surface-active compounds are produced by microoaganisms. These molecules reduce surface tension both aqueous solutions and hydrocarbon mixtures. In this study, isolation and identification of biosurfactant producing bacteria were assessed. The potential application of these bacteria in petroleum industry was investigated. Samples (crude oil were collected from oil wells and 45 strains were isolated. To confirm the ability of isolates in biosurfactant production, haemolysis test, emulsification test and measurement of surface tension were conducted. We also evaluated the effect of different pH, salinity concentrations, and temperatures on biosurfactant production. Among importance features of the isolated strains, one of the strains (NO.4: Bacillus.sp showed high salt tolerance and their successful production of biosurfactant in a vast pH and temperature domain and reduced surface tension to value below 40 mN/m. This strain is potential candidate for microbial enhanced oil recovery. The strain4 biosurfactant component was mainly glycolipid in nature.

  11. Isolation and identification of phytoestrogens and flavonoids in an Ayurvedic proprietary medicine using chromatographic and Mass Spectroscopic analysis

    Institute of Scientific and Technical Information of China (English)

    Sulaiman CT; Arun A; Anandan EM; Sandhya CR; Indira Balachandran

    2015-01-01

    Objective: To develop analytical methods for the isolation and structural identification of poly phenols including phytoestrogens in Mensokot tablet, a herbal proprietary medicine. Methods:Isolation consisted of an ultrasound-assisted extraction, followed by acid hydrolysis and a final liquid-liquid extraction step in diethyl ether. Identification and structural characterisation was done by liquid chromatography coupled with Q-TOF-ESI-MS/MS analysis. Results:Phytoestrogens such as Coumestrol, Genistein and Glycitein have been identified in Mensokot tablet along with several other flavonoids. Conclusion: In the present research, a rapid HPLC-MS/MS method has been developed for the identification of phytoestrogens and other flavonoids from an Ayurvedic proprietary medicine. Phytoestrogens are considered to play an important role in the prevention of cancers, heart disease, menopausal symptoms and osteoporosis.

  12. Accelerated deflation promotes homogeneous airspace liquid distribution in the edematous lung.

    Science.gov (United States)

    Wu, You; Nguyen, Tam L; Perlman, Carrie E

    2017-04-01

    Edematous lungs contain regions with heterogeneous alveolar flooding. Liquid is trapped in flooded alveoli by a pressure barrier-higher liquid pressure at the border than in the center of flooded alveoli-that is proportional to surface tension, T Stress is concentrated between aerated and flooded alveoli, to a degree proportional to T Mechanical ventilation, by cyclically increasing T , injuriously exacerbates stress concentrations. Overcoming the pressure barrier to redistribute liquid more homogeneously between alveoli should reduce stress concentration prevalence and ventilation injury. In isolated rat lungs, we test whether accelerated deflation can overcome the pressure barrier and catapult liquid out of flooded alveoli. We generate a local edema model with normal T by microinfusing liquid into surface alveoli. We generate a global edema model with high T by establishing hydrostatic edema, which does not alter T , and then gently ventilating the edematous lungs, which increases T at 15 cmH 2 O transpulmonary pressure by 52%. Thus ventilation of globally edematous lungs increases T , which should increase stress concentrations and, with positive feedback, cause escalating ventilation injury. In the local model, when the pressure barrier is moderate, accelerated deflation causes liquid to escape from flooded alveoli and redistribute more equitably. Flooding heterogeneity tends to decrease. In the global model, accelerated deflation causes liquid escape, but-because of elevated T -the liquid jumps to nearby, aerated alveoli. Flooding heterogeneity is unaltered. In pulmonary edema with normal T , early ventilation with accelerated deflation might reduce the positive feedback mechanism through which ventilation injury increases over time. NEW & NOTEWORTHY We introduce, in the isolated rat lung, a new model of pulmonary edema with elevated surface tension. We first generate hydrostatic edema and then ventilate gently to increase surface tension. We investigate the

  13. Liquids and liquid mixtures

    CERN Document Server

    Rowlinson, J S; Baldwin, J E; Buckingham, A D; Danishefsky, S

    2013-01-01

    Liquids and Liquid Mixtures, Third Edition explores the equilibrium properties of liquids and liquid mixtures and relates them to the properties of the constituent molecules using the methods of statistical thermodynamics. Topics covered include the critical state, fluid mixtures at high pressures, and the statistical thermodynamics of fluids and mixtures. This book consists of eight chapters and begins with an overview of the liquid state and the thermodynamic properties of liquids and liquid mixtures, including vapor pressure and heat capacities. The discussion then turns to the thermodynami

  14. Passive base isolation with superelastic nitinol SMA helical springs

    International Nuclear Information System (INIS)

    Huang, Bin; Zhang, Haiyang; Wang, Han; Song, Gangbing

    2014-01-01

    Seismic isolation of structures such as multi-story buildings, nuclear reactors, bridges, and liquid storage tanks should be designed to preserve structural integrity. By implementing seismic isolation technology, the deformation of superstructures can be dramatically reduced, consequently helping to protect their safety as well. In this paper, an innovative type of passive base isolation system, which is mainly composed of superelastic nitinol SMA helical springs, is developed. In order to verify the effectiveness of the proposed system, a two-story experimental steel frame model is constructed, and two superelastic SMA helical springs are thermo-mechanically built in the laboratory. To describe the nonlinear mechanical properties of the superelastic SMA helical springs under reciprocating load, a phenomenological model is presented in terms of a series of tensile tests. Afterwards, a numerical model of the two-story frame with the suggested isolation system is set up to simulate the response of the isolated frame subjected to an earthquake. Both the experimental and the numerical simulation results indicate that the proposed base isolation system can remarkably suppress structural vibrations and has improved isolation effects when compared with a steel spring isolation system. Due to the capabilities of energy dissipation as well as fully re-centering, it is very applicable to utilize the suggested isolation system in base isolated structures to resist earthquakes. (paper)

  15. Glass and liquid phase diagram of a polyamorphic monatomic system

    Science.gov (United States)

    Reisman, Shaina; Giovambattista, Nicolas

    2013-02-01

    We perform out-of-equilibrium molecular dynamics (MD) simulations of a monatomic system with Fermi-Jagla (FJ) pair potential interactions. This model system exhibits polyamorphism both in the liquid and glass state. The two liquids, low-density (LDL) and high-density liquid (HDL), are accessible in equilibrium MD simulations and can form two glasses, low-density (LDA) and high-density amorphous (HDA) solid, upon isobaric cooling. The FJ model exhibits many of the anomalous properties observed in water and other polyamorphic liquids and thus, it is an excellent model system to explore qualitatively the thermodynamic properties of such substances. The liquid phase behavior of the FJ model system has been previously characterized. In this work, we focus on the glass behavior of the FJ system. Specifically, we perform systematic isothermal compression and decompression simulations of LDA and HDA at different temperatures and determine "phase diagrams" for the glass state; these phase diagrams varying with the compression/decompression rate used. We obtain the LDA-to-HDA and HDA-to-LDA transition pressure loci, PLDA-HDA(T) and PHDA-LDA(T), respectively. In addition, the compression-induced amorphization line, at which the low-pressure crystal (LPC) transforms to HDA, PLPC-HDA(T), is determined. As originally proposed by Poole et al. [Phys. Rev. E 48, 4605 (1993)], 10.1103/PhysRevE.48.4605 simulations suggest that the PLDA-HDA(T) and PHDA-LDA(T) loci are extensions of the LDL-to-HDL and HDL-to-LDL spinodal lines into the glass domain. Interestingly, our simulations indicate that the PLPC-HDA(T) locus is an extension, into the glass domain, of the LPC metastability limit relative to the liquid. We discuss the effects of compression/decompression rates on the behavior of the PLDA-HDA(T), PHDA-LDA(T), PLPC-HDA(T) loci. The competition between glass polyamorphism and crystallization is also addressed. At our "fast rate," crystallization can be partially suppressed and the

  16. Isolation and culture of protoplast from leaves of Lactuca sativa

    Directory of Open Access Journals (Sweden)

    Witool Chaipakdee

    2007-07-01

    Full Text Available Protoplasts were isolated from leaves of lettuce (Lactuca sativa L. seedlings after in vitro germination for 25, 30, 40 and 50 days. The leaves were stripped and incubated in various combinations of cellulase and pectinase. Protoplasts were cultured on MS medium containing various kinds and concentrations of plant growth regulators in different culture systems including liquid media, hanging, drop culture and solid media. Results revealed that the highest number of viable protoplasts, 14.1x105 cells per gram of fresh weight, was obtained from 30 day-old leaves of lettuce seedlings and isolated by using 2% cellulase in combination with 1% pectinase. Liquid MS medium supplemented with 0.5 mg/l NAA and 0.5 mg/l BA promoted the highest cell division up to 17.67%. First division of protoplasts was observed at 4 days after culture and microcolony formation occurred at the 4th week after culturing. Unfortunately, neither callus formation nor plantlet regeneration were obtained.

  17. Crystal structure of an EAL domain in complex with reaction product 5'-pGpG.

    Directory of Open Access Journals (Sweden)

    Julien Robert-Paganin

    Full Text Available FimX is a large multidomain protein containing an EAL domain and involved in twitching motility in Pseudomonas aeruginosa. We present here two crystallographic structures of the EAL domain of FimX (residues 438-686: one of the apo form and the other of a complex with 5'-pGpG, the reaction product of the hydrolysis of c-di-GMP. In both crystal forms, the EAL domains form a dimer delimiting a large cavity encompassing the catalytic pockets. The ligand is trapped in this cavity by its sugar phosphate moiety. We confirmed by NMR that the guanine bases are not involved in the interaction in solution. We solved here the first structure of an EAL domain bound to the reaction product 5'-pGpG. Though isolated FimX EAL domain has a very low catalytic activity, which would not be significant compared to other catalytic EAL domains, the structure with the product of the reaction can provides some hints in the mechanism of hydrolysis of the c-di-GMP by EAL domains.

  18. Crystal structure of an EAL domain in complex with reaction product 5'-pGpG.

    Science.gov (United States)

    Robert-Paganin, Julien; Nonin-Lecomte, Sylvie; Réty, Stéphane

    2012-01-01

    FimX is a large multidomain protein containing an EAL domain and involved in twitching motility in Pseudomonas aeruginosa. We present here two crystallographic structures of the EAL domain of FimX (residues 438-686): one of the apo form and the other of a complex with 5'-pGpG, the reaction product of the hydrolysis of c-di-GMP. In both crystal forms, the EAL domains form a dimer delimiting a large cavity encompassing the catalytic pockets. The ligand is trapped in this cavity by its sugar phosphate moiety. We confirmed by NMR that the guanine bases are not involved in the interaction in solution. We solved here the first structure of an EAL domain bound to the reaction product 5'-pGpG. Though isolated FimX EAL domain has a very low catalytic activity, which would not be significant compared to other catalytic EAL domains, the structure with the product of the reaction can provides some hints in the mechanism of hydrolysis of the c-di-GMP by EAL domains.

  19. Liquid-liquid displacement in slippery liquid-infused membranes (SLIMs)

    OpenAIRE

    Bazyar, Hanieh; Lv, Pengyu; Wood, Jeffery A.; Porada, Slawomir; Lohse, Detlef; Lammertink, Rob G. H.

    2018-01-01

    Liquid-infused membranes inspired by slippery liquid-infused porous surfaces (SLIPS) have been recently introduced to membrane technology. The gating mechanism of these membranes is expected to give rise to anti-fouling properties and multi-phase transport capabilities. However, the long-term retention of the infusion liquid has not yet been explored. To address this issue, we investigate the retention of the infusion liquid in slippery liquid-infused membranes (SLIMs) via liquid-liquid displ...

  20. Seismic Response Analysis and Design of Structure with Base Isolation

    International Nuclear Information System (INIS)

    Rosko, Peter

    2010-01-01

    The paper reports the study on seismic response and energy distribution of a multi-story civil structure. The nonlinear analysis used the 2003 Bam earthquake acceleration record as the excitation input to the structural model. The displacement response was analyzed in time domain and in frequency domain. The displacement and its derivatives result energy components. The energy distribution in each story provides useful information for the structural upgrade with help of added devices. The objective is the structural displacement response minimization. The application of the structural seismic response research is presented in base-isolation example.

  1. An Improved Quick Method for the Isolation of Total RNA from Cotton ...

    African Journals Online (AJOL)

    David PANG

    2011-11-02

    Nov 2, 2011 ... in liquid nitrogen in a mortar and pestle and stored until. RNA isolation. ... our laboratory for microarray analysis, cDNA pyro- sequencing studies and construction ..... Economic and rapid method for extracting cotton genomic ...

  2. Kinase Associated-1 Domains Drive MARK/PAR1 Kinases to Membrane Targets by Binding Acidic Phospholipids

    Energy Technology Data Exchange (ETDEWEB)

    Moravcevic, Katarina; Mendrola, Jeannine M.; Schmitz, Karl R.; Wang, Yu-Hsiu; Slochower, David; Janmey, Paul A.; Lemmon, Mark A. (UPENN-MED)

    2011-09-28

    Phospholipid-binding modules such as PH, C1, and C2 domains play crucial roles in location-dependent regulation of many protein kinases. Here, we identify the KA1 domain (kinase associated-1 domain), found at the C terminus of yeast septin-associated kinases (Kcc4p, Gin4p, and Hsl1p) and human MARK/PAR1 kinases, as a membrane association domain that binds acidic phospholipids. Membrane localization of isolated KA1 domains depends on phosphatidylserine. Using X-ray crystallography, we identified a structurally conserved binding site for anionic phospholipids in KA1 domains from Kcc4p and MARK1. Mutating this site impairs membrane association of both KA1 domains and intact proteins and reveals the importance of phosphatidylserine for bud neck localization of yeast Kcc4p. Our data suggest that KA1 domains contribute to coincidence detection, allowing kinases to bind other regulators (such as septins) only at the membrane surface. These findings have important implications for understanding MARK/PAR1 kinases, which are implicated in Alzheimer's disease, cancer, and autism.

  3. Procedure of identification of fullerenes isolated from iron-carbon alloys

    International Nuclear Information System (INIS)

    Zakirnichnaya, M.M.

    2001-01-01

    A method of fullerenes isolation from the structure of iron-carbon alloys and their identification using physical methods which provide determination of the different parameters of nanoobjects is developed. Qualitative (mass-spectrometry of positive and negative ions, small angle X-ray scattering) and quantitative (IR-spectrometry, liquid chromatography) evaluation of fullerenes in the samples obtained from iron-carbon alloys and their visual observation using scanning tunnel microscopy are performed. It is found that the method provides isolation and identification of fullerenes present in the structure of steels and irons [ru

  4. Screening of Norharmane from Seven Cyanobacteria by High-performance Liquid Chromatography.

    Science.gov (United States)

    Karan, Tunay; Erenler, Ramazan

    2017-10-01

    Cyanobacteria, including pharmaceutically and medicinally valuable compounds attract the great attention lately. Norharmane (9H-pyrido (3,4-b) indole found in some cyanobacteria revealed a great number of biological effects. Seven cyanobacteria were isolated and identified from Yesilirmak River and Gaziosmanpasa University Campus to determine the norharmane content. Cyanobacteria collected from Tokat, Turkey were isolated and identified by morphologically. Norharmane (9H-pyrido [3,4-b] indole) quantities were presented for seven cyanobacteria, Chroococcus minutus (Kütz.) Nägeli, Geitlerinema carotinosum (Geitler) Anagnostidis, Nostoc linckia Bornet ex Bornet and Flahault, Anabaena oryzae F. E. Fritsch, Oscillatoria limnetica Lemmermann, Phormidium sp . Kützing ex Gomont, and Cylindrospermum sp . Kutzing ex E. Bornet and C. Flahault by high-performance liquid chromatography. The norharmane amount indicated for cyanobacterial culture media altered in a species-dependent kind in the range of 0.81-10.87 μg/g. C. minutus produced the most norharmane among the investigated cyanobacteria as 10.87 μg/g. Cyanobacteria could be an important source of norharmane as well as pharmaceutically valuable compounds. Seven cyanobacteria were isolated and identified from Yesilirmak RiverQuantitative analysis of norharmane was executed on isolated cyanobacteriaFour cyanobecteria species included the norharmane Chroococcus minutus contained the most norharmane (10.87 μg/g). Abbreviations used: HPLC: High performance liquid chromatograph.

  5. Screening of Norharmane from Seven Cyanobacteria by High-performance Liquid Chromatography

    Science.gov (United States)

    Karan, Tunay; Erenler, Ramazan

    2017-01-01

    Background: Cyanobacteria, including pharmaceutically and medicinally valuable compounds attract the great attention lately. Norharmane (9H-pyrido (3,4-b) indole found in some cyanobacteria revealed a great number of biological effects. Objective: Seven cyanobacteria were isolated and identified from Yesilirmak River and Gaziosmanpasa University Campus to determine the norharmane content. Materials and Methods: Cyanobacteria collected from Tokat, Turkey were isolated and identified by morphologically. Norharmane (9H-pyrido [3,4-b] indole) quantities were presented for seven cyanobacteria, Chroococcus minutus (Kütz.) Nägeli, Geitlerinema carotinosum (Geitler) Anagnostidis, Nostoc linckia Bornet ex Bornet and Flahault, Anabaena oryzae F. E. Fritsch, Oscillatoria limnetica Lemmermann, Phormidium sp. Kützing ex Gomont, and Cylindrospermum sp. Kutzing ex E. Bornet and C. Flahault by high-performance liquid chromatography. Results: The norharmane amount indicated for cyanobacterial culture media altered in a species-dependent kind in the range of 0.81–10.87 μg/g. C. minutus produced the most norharmane among the investigated cyanobacteria as 10.87 μg/g. Conclusion: Cyanobacteria could be an important source of norharmane as well as pharmaceutically valuable compounds. SUMMARY Seven cyanobacteria were isolated and identified from Yesilirmak RiverQuantitative analysis of norharmane was executed on isolated cyanobacteriaFour cyanobecteria species included the norharmaneChroococcus minutus contained the most norharmane (10.87 μg/g). Abbreviations used: HPLC: High performance liquid chromatograph. PMID:29142439

  6. Topology-generating interfacial pattern formation during liquid metal dealloying.

    Science.gov (United States)

    Geslin, Pierre-Antoine; McCue, Ian; Gaskey, Bernard; Erlebacher, Jonah; Karma, Alain

    2015-11-19

    Liquid metal dealloying has emerged as a novel technique to produce topologically complex nanoporous and nanocomposite structures with ultra-high interfacial area and other unique properties relevant for diverse material applications. This process is empirically known to require the selective dissolution of one element of a multicomponent solid alloy into a liquid metal to obtain desirable structures. However, how structures form is not known. Here we demonstrate, using mesoscale phase-field modelling and experiments, that nano/microstructural pattern formation during dealloying results from the interplay of (i) interfacial spinodal decomposition, forming compositional domain structures enriched in the immiscible element, and (ii) diffusion-coupled growth of the enriched solid phase and the liquid phase into the alloy. We highlight how those two basic mechanisms interact to yield a rich variety of topologically disconnected and connected structures. Moreover, we deduce scaling laws governing microstructural length scales and dealloying kinetics.

  7. The concepts of liquid metal of IV generation

    International Nuclear Information System (INIS)

    Carbonnier, J. L.

    2005-01-01

    The concepts of liquid metals, due to their large spectrum, show important possibility of sustainable development: two concepts of liquid metal (Sodium and Lead) were engaged in the frame of the IV generation. The reactors with sodium benefit from considerable background of experience and of important work on projects to aim at the price diminution and the increase of safety (EFR, JSFR). The commitment of Japan as a leader of this concept and the support by France allow to contemplate an industrial deployment from 2015. The lead reactors offer some advantages in the domain of safety but otherwise require a highly important research and development binded to the control of the corrosion, the perspective of deployment of this concept are more hypothetical

  8. UK contribution to CEGB-EPRI-CRIEPI program on seismic isolation

    International Nuclear Information System (INIS)

    Austin, N.M.; Hattori, S.; Rodwell, E.; Womack, G.J.

    1989-01-01

    Over the last decade the concept of seismic isolation applied to nuclear power plants has generated a great deal of interest worldwide and a number of comprehensive reviews on the topic have been published. Understandably, most of the design and research and development (R and D) effort on seismic isolation has come from countries where larger magnitude earthquakes are an ever-present problem; e.g., Japan, USA, etc. In some areas of these countries seismic isolation may in fact present the only feasible design solution for potential sites of Liquid-Metal-Cooled Reactors (LMR's). This paper summarizes the test results obtained from a small scale seismic isolation system consisting of a laminated steel/natural rubber bearing and a viscodamper. Dynamic characteristics of the system; e.g., stiffness and damping, were measured for a variety of loading conditions. The results are suitable for developing a mathematical model of the isolation system and providing data for use in the design of larger scale bearings and viscodampers

  9. Treatment of radioactive liquid organic waste using bacteria community

    International Nuclear Information System (INIS)

    Rafael Vicente de Padua Ferreira; Solange Kazumi Sakata; Maria Helena Bellini; Julio Takehiro Marumo; Fernando Dutra; Patricia Busko Di Vitta; Maria Helena Tirollo Taddei

    2012-01-01

    Waste management plays an important role in radioactive waste volume reduction as well as lowering disposal costs and minimizing the environment-detrimental impact. The employment of biomass in the removal of heavy metals and radioisotopes has a significant potential in liquid waste treatment. The aim of this study is to evaluate the radioactive waste treatment by using three different bacterial communities (BL, BS, and SS) isolated from impacted areas, removing radioisotopes and organic compounds. The best results were obtained in the BS and BL community, isolated from the soil and a lake of a uranium mine, respectively. BS community was able to remove 92% of the uranium and degraded 80% of tributyl phosphate and 70% of the ethyl acetate in 20 days of experiments. BL community removed 81% of the uranium and degraded nearly 60% of the TBP and 70% of the ethyl acetate. SS community collected from the sediment of Sao Sebastiao channel removed 76% of the uranium and 80% of the TBP and 70% of the ethyl acetate. Both americium and cesium were removed by all communities. In addition, the BS community showed to be more resistant to radioactive liquid waste than the other communities. These results indicated that the BS community is the most viable for the treatment of large volumes of radioactive liquid organic waste. (author)

  10. Genetic diversity of Clavispora lusitaniae isolated from Agave fourcroydes Lem, as revealed by DNA fingerprinting.

    Science.gov (United States)

    Pérez-Brito, Daisy; Magaña-Alvarez, Anuar; Lappe-Oliveras, Patricia; Cortes-Velazquez, Alberto; Torres-Calzada, Claudia; Herrera-Suarez, Teófilo; Larqué-Saavedra, Alfonso; Tapia-Tussell, Raul

    2015-01-01

    This study characterized Clavispora lusitaniae strains isolated from different stages of the processing and early fermentation of a henequen (Agave fourcroydes) spirit produced in Yucatan, Mexico using a molecular technique. Sixteen strains identified based on morphological features, obtained from different substrates, were typed molecularly. Nine different versions of the divergent D1/D2 domain of the large-subunit ribosomal DNA sequence were identified among the C. lusitaniae strains. The greatest degree of polymorphism was found in the 90-bp structural motif of the D2 domain. The MSP-PCR technique was able to differentiate 100% of the isolates. This study provides significant insight into the genetic diversity of the mycobiota present during the henequen fermentation process, especially that of C. lusitaniae, for which only a few studies in plants have been published. The applied MSP-PCR markers were very efficient in revealing olymorphisms between isolates of this species.

  11. Mycobacterium minnesotense sp. nov., a photochromogenic bacterium isolated from sphagnum peat bogs.

    Science.gov (United States)

    Hannigan, Geoffrey D; Krivogorsky, Bogdana; Fordice, Daniel; Welch, Jacqueline B; Dahl, John L

    2013-01-01

    Several intermediate-growing, photochromogenic bacteria were isolated from sphagnum peat bogs in northern Minnesota, USA. Acid-fast staining and 16S rRNA gene sequence analysis placed these environmental isolates in the genus Mycobacterium, and colony morphologies and PCR restriction analysis patterns of the isolates were similar. Partial sequences of hsp65 and dnaJ1 from these isolates showed that Mycobacterium arupense ATCC BAA-1242(T) was the closest mycobacterial relative, and common biochemical characteristics and antibiotic susceptibilities existed between the isolates and M. arupense ATCC BAA-1242(T). However, compared to nonchromogenic M. arupense ATCC BAA-1242(T), the environmental isolates were photochromogenic, had a different mycolic acid profile and had reduced cell-surface hydrophobicity in liquid culture. The data reported here support the conclusion that the isolates are representatives of a novel mycobacterial species, for which the name Mycobacterium minnesotense sp. nov. is proposed. The type strain is DL49(T) (=DSM 45633(T) = JCM 17932(T) = NCCB 100399(T)).

  12. Degradation diagnosis of transformer insulating oils with terahertz time-domain spectroscopy

    Science.gov (United States)

    Kang, Seung Beom; Kim, Won-Seok; Chung, Dong Chul; Joung, Jong Man; Kwak, Min Hwan

    2017-12-01

    We report the frequency-dependent complex optical constants, refractive index and absorption, and complex dielectric properties over the frequency range from 0.2 to 3.0 THz for aged power transformer mineral insulating oils. These results have been obtained using terahertz time-domain spectroscopy (THz-TDS) and demonstrate the double-Debye relaxation behavior of the mineral insulating oil. The measured complex optical and dielectric characteristics can be important benchmarks for liquid molecular dynamics and theoretical studies of insulating oils. Due to clear differences in THz responses of aged mineral insulating oils, THz-TDS can be used as a novel on-site diagnostic technique to monitor the insulation condition in aged power transformers and may be valuable alternative to characterize other developing eco-friendly insulating oils and industrial liquids.

  13. CASH AND LIQUIDITY/LIQUIDITY AND LIQUIDITY RATIO

    Directory of Open Access Journals (Sweden)

    BEATRIX LIGHEZAN BREUER

    2012-12-01

    Full Text Available The present paper aims to present the correlation as well as the differences between liquidity/cash and liquidity ratio in terms of economic entities. Researches on this topic are based on the opinions of some specialists in accounting and in the economic-financial analysis, as well as on the national legal stipulations and the ones set out in the International Accounting Standards, the Financial report, respectively. The object of this paper is represented by the correlation between liquidity/cash and liquidity ratios representing the liquidity as current assets, assets implied in the determination of liquidity ratios. The end of the paper consists of the conclusions drawn from the issues presented in the paper but also our views on this research topic.

  14. Proteins with Intrinsically Disordered Domains Are Preferentially Recruited to Polyglutamine Aggregates.

    Directory of Open Access Journals (Sweden)

    Maggie P Wear

    Full Text Available Intracellular protein aggregation is the hallmark of several neurodegenerative diseases. Aggregates formed by polyglutamine (polyQ-expanded proteins, such as Huntingtin, adopt amyloid-like structures that are resistant to denaturation. We used a novel purification strategy to isolate aggregates formed by human Huntingtin N-terminal fragments with expanded polyQ tracts from both yeast and mammalian (PC-12 cells. Using mass spectrometry we identified the protein species that are trapped within these polyQ aggregates. We found that proteins with very long intrinsically-disordered (ID domains (≥ 100 amino acids and RNA-binding proteins were disproportionately recruited into aggregates. The removal of the ID domains from selected proteins was sufficient to eliminate their recruitment into polyQ aggregates. We also observed that several neurodegenerative disease-linked proteins were reproducibly trapped within the polyQ aggregates purified from mammalian cells. Many of these proteins have large ID domains and are found in neuronal inclusions in their respective diseases. Our study indicates that neurodegenerative disease-associated proteins are particularly vulnerable to recruitment into polyQ aggregates via their ID domains. Also, the high frequency of ID domains in RNA-binding proteins may explain why RNA-binding proteins are frequently found in pathological inclusions in various neurodegenerative diseases.

  15. Relaxation and transport properties of liquid n-triacontane

    International Nuclear Information System (INIS)

    Kondratyuk, N D; Lankin, A V; Norman, G E; Stegailov, V V

    2015-01-01

    Molecular modelling is used to calculate transport properties and to study relaxation of liquid n-triacontane (C 30 H 62 ). The problem is important in connection with the behavior of liquid isolators in a pre-breakdown state. Two all-atom models and a united-atom model are used. Shear viscosity is calculated using the Green-Kubo formula. The force fields are compared with each other using the following criteria: the required time for one molecular dynamics step, the compliance of the main physical and transport properties with experimental values. The problem of the system equilibration is considered. The united-atom potential is used to model the n-triacontane liquid with an initial directional orientation. The time of relaxation to the disordered state, when all molecules orientations are randomized, are obtained. The influence of the molecules orientations on the shear viscosity value and the shear viscosity relaxation are treated. (paper)

  16. Study of liquids and solutions

    International Nuclear Information System (INIS)

    Bellissent-Funel, M.C.

    1994-01-01

    A critical review of what has been achieved on the structure of liquids and solutions and the capabilities and developments of neutron scattering in this domain, are presented. A great variety of simple to complex systems has been investigated with the aim of obtaining a full microscopic description of the structure. Selected examples demonstrate the neutron scattering determination of interaction potentials, intermolecular structures and partial structure factors of complex systems. The isotopic substitution method is illustrated by the application to the study of the solvation of ions in aqueous and non aqueous solutions. (author). 9 figs., 32 refs

  17. Characterization of phosphorylation sites in the cytoplasmic domain of the 300 kDa mannose-6-phosphate receptor

    DEFF Research Database (Denmark)

    Rosorius, O; Mieskes, G; Issinger, O G

    1993-01-01

    The human 300 kDa mannose-6-phosphate receptor (MPR 300) is phosphorylated in vivo at serine residues of its cytoplasmic domain. Two-dimensional separation can resolve tryptic phosphopeptides into four major species. To identify the kinases involved in MPR 300 phosphorylation and the phosphorylat......The human 300 kDa mannose-6-phosphate receptor (MPR 300) is phosphorylated in vivo at serine residues of its cytoplasmic domain. Two-dimensional separation can resolve tryptic phosphopeptides into four major species. To identify the kinases involved in MPR 300 phosphorylation...... and the phosphorylation sites the entire coding sequence of the cytoplasmic tail was expressed in Escherichia coli. The isolated cytoplasmic domain was used as a substrate for four purified serine/threonine kinases [casein kinase II (CK II), protein kinase A (PKA), protein kinase C and Ca2+/calmodulin kinase]. All...... kinases phosphorylate the cytoplasmic tail exclusively on serine residues. Inhibition studies using synthetic peptides, partial sequencing of isolated tryptic phosphopeptides and co-migration with tryptic phosphopeptides from MPR 300 labelled in vivo showed that (i) PKA phosphorylates the cytoplasmic MPR...

  18. The CRM domain: an RNA binding module derived from an ancient ribosome-associated protein.

    Science.gov (United States)

    Barkan, Alice; Klipcan, Larik; Ostersetzer, Oren; Kawamura, Tetsuya; Asakura, Yukari; Watkins, Kenneth P

    2007-01-01

    The CRS1-YhbY domain (also called the CRM domain) is represented as a stand-alone protein in Archaea and Bacteria, and in a family of single- and multidomain proteins in plants. The function of this domain is unknown, but structural data and the presence of the domain in several proteins known to interact with RNA have led to the proposal that it binds RNA. Here we describe a phylogenetic analysis of the domain, its incorporation into diverse proteins in plants, and biochemical properties of a prokaryotic and eukaryotic representative of the domain family. We show that a bacterial member of the family, Escherichia coli YhbY, is associated with pre-50S ribosomal subunits, suggesting that YhbY functions in ribosome assembly. GFP fused to a single-domain CRM protein from maize localizes to the nucleolus, suggesting that an analogous activity may have been retained in plants. We show further that an isolated maize CRM domain has RNA binding activity in vitro, and that a small motif shared with KH RNA binding domains, a conserved "GxxG" loop, contributes to its RNA binding activity. These and other results suggest that the CRM domain evolved in the context of ribosome function prior to the divergence of Archaea and Bacteria, that this function has been maintained in extant prokaryotes, and that the domain was recruited to serve as an RNA binding module during the evolution of plant genomes.

  19. Purification of flavonoids from licorice using an off-line preparative two-dimensional normal-phase liquid chromatography/reversed-phase liquid chromatography method.

    Science.gov (United States)

    Fan, Yunpeng; Fu, Yanhui; Fu, Qing; Cai, Jianfeng; Xin, Huaxia; Dai, Mei; Jin, Yu

    2016-07-01

    An orthogonal (71.9%) off-line preparative two-dimensional normal-phase liquid chromatography/reversed-phase liquid chromatography method coupled with effective sample pretreatment was developed for separation and purification of flavonoids from licorice. Most of the nonflavonoids were firstly removed using a self-made Click TE-Cys (60 μm) solid-phase extraction. In the first dimension, an industrial grade preparative chromatography was employed to purify the crude flavonoids. Click TE-Cys (10 μm) was selected as the stationary phase that provided an excellent separation with high reproducibility. Ethyl acetate/ethanol was selected as the mobile phase owing to their excellent solubility for flavonoids. Flavonoids co-eluted in the first dimension were selected for further purification using reversed-phase liquid chromatography. Multiple compounds could be isolated from one normal-phase fraction and some compounds with bad resolution in one-dimensional liquid chromatography could be prepared in this two-dimensional system owing to the orthogonal separation. Moreover, this two-dimensional liquid chromatography method was beneficial for the preparation of relatively trace flavonoid compounds, which were enriched in the first dimension and further purified in the second dimension. Totally, 24 flavonoid compounds with high purity were obtained. The results demonstrated that the off-line two-dimensional liquid chromatography method was effective for the preparative separation and purification of flavonoids from licorice. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Identification and characterization of B-cell epitopes in the DBL4e domain of VAR2CSA

    DEFF Research Database (Denmark)

    Ditlev, Sisse B; Nielsen, Morten A; Resende, Mafalda

    2012-01-01

    and is the leading candidate for a placental malaria vaccine. Antibodies induced in rats against the recombinant DBL4e domain of VAR2CSA inhibit the binding of a number of laboratory and field parasite isolates to CSA. In this study, we used a DBL4e peptide-array to identify epitopes targeted by DBL4e...... might be involved in the induction of inhibitory antibodies induced by the recombinant DBL4e domain....

  1. Isolation of a urinary digitalis-like factor indistinguishable from digoxin

    Energy Technology Data Exchange (ETDEWEB)

    Goto, A.; Ishiguro, T.; Yamada, K.; Ishii, M.; Yoshioka, M.; Eguchi, C.; Shimora, M.; Sugimoto, T. (Univ. of Tokyo (Japan))

    1990-12-31

    A digitalis-like factor has been purified to apparent homogeneity from human urine based on the inhibitory effect on ({sup 3}H) ouabain binding to intact human erythrocytes. The purification scheme involved large scale adsorption followed by preparative, semipreparative and analytical high-performance liquid chromatography. The purified material showed a prominent digoxin-like immunoreactivity. The behaviour of the isolated substance was identical to that of authentic digoxin in three high-performance liquid chromatography and three thin-layer chromatography systems. Moreover, fast atom bombardment mass spectrum and proton nuclear magnetic resonance spectrum suggested that the purified material may be indistinguishable from digoxin.

  2. (Liquid + liquid) equilibria of perfluorocarbons with fluorinated ionic liquids

    International Nuclear Information System (INIS)

    Martinho, S.; Araújo, J.M.M.; Rebelo, L.P.N.; Pereiro, A.B.; Marrucho, I.M.

    2013-01-01

    Highlights: • (Liquid + liquid) equilibria perfluorocarbons and fluorinated ionic liquids. • Non-Random Two Liquid model was successfully applied. • Thermodynamic functions that describe the solvation process were calculated. -- Abstract: In order to evaluate the feasibility of partially replace perfluorocarbons (PFCs) with fluorinated ionic liquids (FILs) in PFCs-in-water emulsions, usually used for biomedical purposes, herein the (liquid + liquid) phase equilibria of FILs containing fluorinated chains longer than four carbons with PFCs were carried out in a wide range of temperatures. With this goal in mind, two PFCs (perfluorooctane and perfluorodecalin) were selected and the (liquid + liquid) equilibria of the binary mixtures of these PFCs and FILs were studied at atmospheric pressure in a temperature range from T (293.15 to 343.15) K. For these studies, FILs containing ammonium, pyridinium and imidazolium cations and different anions with fluorocarbon alkyl chains between 4 and 8 were included. Additionally, Non-Random Two Liquid (NRTL) thermodynamic model was successfully applied to correlate the behaviour of the PFCs + FILs binary mixtures. Moreover, thermodynamic functions that describe the solvation process were calculated from the experimental data

  3. Theoretical analysis of the vibration of axisymmetric liquid bridges of arbitrary shape

    Energy Technology Data Exchange (ETDEWEB)

    Montanero, J.M. [Departamento de Electronica e Ingenieria Electromecanica, Universidad de Extremadura, 06071 Badajoz (Spain)

    2003-01-01

    A liquid bridge consists of a mass of liquid sustained by the action of capillary forces between two parallel disks. The dynamics of these liquid columns has been extensively analysed both theoretically and experimentally over the last decades. Many of the studies have focused on the dynamical response of cylindrical liquid bridges subjected to the action of an oscillatory microgravity field due to, for instance, an in-phase vibration of the supporting disks. There have been fewer studies dealing with the vibration of axisymmetric liquid bridges of arbitrary shape. In this paper the dynamics of rotating inviscid axisymmetric liquid bridges is analysed considering the combined effect of residual gravity, the inequality of the disks and the liquid bridge volume. The results are calculated numerically by using the one-dimensional Cosserat model and the full three-dimensional description. The excitation is assumed to be of small amplitude and harmonic, so that the theoretical models are linearized and the analysis is performed in the frequency domain. The details of the numerical methods proposed are discussed. Comparison between the values of the first resonance frequency obtained from both models shows an excellent agreement for long liquid bridges, the discrepancies increasing as the value of the slenderness decreases. (orig.)

  4. Conservation patterns of HIV-1 RT connection and RNase H domains: identification of new mutations in NRTI-treated patients.

    Directory of Open Access Journals (Sweden)

    André F A Santos

    Full Text Available BACKGROUND: Although extensive HIV drug resistance information is available for the first 400 amino acids of its reverse transcriptase, the impact of antiretroviral treatment in C-terminal domains of Pol (thumb, connection and RNase H is poorly understood. METHODS AND FINDINGS: We wanted to characterize conserved regions in RT C-terminal domains among HIV-1 group M subtypes and CRF. Additionally, we wished to identify NRTI-related mutations in HIV-1 RT C-terminal domains. We sequenced 118 RNase H domains from clinical viral isolates in Brazil, and analyzed 510 thumb and connection domain and 450 RNase H domain sequences collected from public HIV sequence databases, together with their treatment status and histories. Drug-naïve and NRTI-treated datasets were compared for intra- and inter-group conservation, and differences were determined using Fisher's exact tests. One third of RT C-terminal residues were found to be conserved among group M variants. Three mutations were found exclusively in NRTI-treated isolates. Nine mutations in the connection and 6 mutations in the RNase H were associated with NRTI treatment in subtype B. Some of them lay in or close to amino acid residues which contact nucleic acid or near the RNase H active site. Several of the residues pointed out herein have been recently associated to NRTI exposure or increase drug resistance to NRTI. CONCLUSIONS: This is the first comprehensive genotypic analysis of a large sequence dataset that describes NRTI-related mutations in HIV-1 RT C-terminal domains in vivo. The findings into the conservation of RT C-terminal domains may pave the way to more rational drug design initiatives targeting those regions.

  5. [Isolation of actinobacteria with antibiotic associated with soft coral Nephthea sp].

    Science.gov (United States)

    Ma, Liang; Zhang, Wenjun; Zhu, Yiguang; Wu, Zhengchao; Saurav, Kumar; Hang, Hui; Zhang, Changsheng

    2013-10-04

    The present study aims to isolate and identify actinobacteria associated with the soft coral Nephthea sp., and to isolate natural products from these actinobacteria under the guidance of PCR screening for polyketides synthase (PKS) genes. Eleven selective media were used to isolate actinobacteria associated with the soft coral Nephthea sp. collected from Yongxin Island. The isolated actinobacteria were classified on the basis of phylogenetic tree analysis of their 16S rRNA genes. Degenerated primers targeted on conserved KS (ketoacyl-synthase) domain of type I PKS genes were used to screen for potential isolates. The positive isolates were cultured in three different media to check their producing profiles. One bioactive strain that is rich in metabolites was subjected to larger scale fermentation for isolating bioactive natural products. A total of 20 strains were isolated from Nephthea sp., and were categorized into 3 genera including Streptomyces, Dietzia and Salinospora, among which 18 strains were positive in screening with type I PKS genes. Two bioactive compounds rifamycin S and rifamycin W were isolated and identified from Salinospora arenicola SH04. This is the first report of isolating indigenous marine actinobacteria Salinospora from the soft coral Nephthea sp. It provides an example of isolating bioactive secondary metabolites from cultivable actinobacteria associated with Nephthea sp. by PCR screening.

  6. Alternaria sp. MG1, a resveratrol-producing fungus: isolation, identification, and optimal cultivation conditions for resveratrol production.

    Science.gov (United States)

    Shi, Junling; Zeng, Qin; Liu, Yanlin; Pan, Zhongli

    2012-07-01

    Due to its potential in preventing or slowing the occurrence of many diseases, resveratrol (3,5,4'-trihydroxystilbene) has attracted great research interest. The objective of this study was to identify microorganisms from selected plants that produce resveratrol and to optimize the conditions for resveratrol production. Endophytes from Merlot wine grapes (Vitis vinifera L. cv. Merlot), wild Vitis (Vitis quinquangularis Rehd.), and Japanese knotweed (Polygonum cuspidatum Siebold & Zucc.) were isolated, and their abilities to produce resveratrol were evaluated. A total of 65 isolates were obtained and 21 produced resveratrol (6-123 μg/L) in liquid culture. The resveratrol-producing isolates belonged to seven genera, Botryosphaeria, Penicillium, Cephalosporium, Aspergillus, Geotrichum, Mucor, and Alternaria. The resveratrol-producing capability decreased or was completely lost in most isolates after three rounds of subculture. It was found that only the strain Alternaria sp. MG1 (isolated from cob of Merlot using GA1 medium) had stable and high resveratrol-producing capability in all subcultures. During liquid cultivation of Alternaria sp. MG1 in potato dextrose medium, the synthesis of resveratrol began on the first day, increased to peak levels on day 7, and then decreased sharply thereafter. Cell growth increased during cultivation and reached a stable and high level of biomass after 5 days. The best fermentation conditions for resveratrol production in liquid cultures of Alternaria sp. MG1 were an inoculum size of 6 %, a medium volume of 125 mL in a 250-mL flask, a rotation speed of 101 rpm, and a temperature of 27 °C.

  7. Bistable (latching) solenoid actuated propellant isolation valve

    Science.gov (United States)

    Wichmann, H.; Deboi, H. H.

    1979-01-01

    The design, fabrication, assembly and test of a development configuration bistable (latching) solenoid actuated propellant isolation valve suitable for the control hydrazine and liquid fluorine to an 800 pound thrust rocket engine is described. The valve features a balanced poppet, utilizing metal bellows, a hard poppet/seat interface and a flexure support system for the internal moving components. This support system eliminates sliding surfaces, thereby rendering the valve free of self generated particles.

  8. Draft Genome Sequences of Klebsiella oxytoca Isolates Originating from a Highly Contaminated Liquid Hand Soap Product

    OpenAIRE

    Hammerl, J. A.; Lasch, P.; Nitsche, A.; Dabrowski, P. W.; Hahmann, H.; Wicke, A.; Kleta, S.; Dahouk, S. Al; Dieckmann, R.

    2015-01-01

    In 2013, contaminated liquid soap was detected by routine microbiological monitoring of consumer products through state health authorities. Because of its high load of Klebsiella oxytoca, the liquid soap was notified via the European Union Rapid Alert System for Dangerous Non-Food Products (EU-RAPEX) and recalled. Here, we present two draft genome sequences and a summary of their general features.

  9. Correlations and transport in vortex liquids

    International Nuclear Information System (INIS)

    Nelson, D.R.

    1991-01-01

    The theory of the vortex line liquids which arise in the copper oxide high temperature superconductors is described. The author discusses correlations in the presence of weak disorder, and the viscous electricity which results when entangled flux liquids attempt to flow past a few strong pins. He shows, using an analogy with single particle quantum mechanics, that thermal fluctuations lead to a large renormalization of the binding energy of an isolated line to planar or linear pins. A related mapping of the statistical mechanics of many flux lines onto the physics of two-dimensional boson superfluids is reviewed, with an emphasis on the physical meaning of phase coherence. He argues that boson localization provides an appropriate description of flux lines when many planar or linear ping are present. A number of experimental tests of the theory are proposed

  10. Technical specifications for the successful fabrication of laminated seismic isolation bearings

    Energy Technology Data Exchange (ETDEWEB)

    Kulak, R F [Argonne National Laboratory, Argonne, IL (United States)

    1992-07-01

    High damping steel-laminated elastomeric seismic isolation bearings are becoming a preferred device for isolating large buildings and structures. In the United States, the current reference design for the Advanced Liquid Metal Reactor uses laminated bearings for seismic isolation. These bearings are constructed from alternating layers of rubber and steel plates. They are typically designed for shear strains between 50 to 100 percent and expected to sustain two to three times these levels for beyond design basis loading considerations. The technical specifications used to procure these bearings are an important factor in assuring thatthe bearings meet the performance requirements of the design. The key aspects of the current version of the Technical Specifications are discussed in this paper. (author)

  11. Frequency-domain analysis of intrinsic neuronal properties using high-resistant electrodes

    Directory of Open Access Journals (Sweden)

    Christian Rössert

    2009-08-01

    Full Text Available Intrinsic cellular properties of neurons in culture or slices are usually studied by the whole cell clamp method using low-resistant patch pipettes. These electrodes allow detailed analyses with standard electrophysiological methods such as current- or voltage-clamp. However, in these preparations large parts of the network and dendritic structures may be removed, thus preventing an adequate study of synaptic signal processing. Therefore, intact in vivo preparations or isolated in vitro whole brains have been used in which intracellular recordings are usually made with sharp, high-resistant electrodes to optimize the impalement of neurons. The general non-linear resistance properties of these electrodes, however, severely limit accurate quantitative studies of membrane dynamics especially needed for precise modelling. Therefore, we have developed a frequency-domain analysis of membrane properties that uses a Piece-wise Non-linear Electrode Compensation (PNEC method. The technique was tested in second-order vestibular neurons and abducens motoneurons of isolated frog whole brain preparations using sharp potassium chloride- or potassium acetate-filled electrodes. All recordings were performed without online electrode compensation. The properties of each electrode were determined separately after the neuronal recordings and were used in the frequency-domain analysis of the combined measurement of electrode and cell. This allowed detailed analysis of membrane properties in the frequency-domain with high-resistant electrodes and provided quantitative data that can be further used to model channel kinetics. Thus, sharp electrodes can be used for the characterization of intrinsic properties and synaptic inputs of neurons in intact brains.

  12. Quorum Sensing Activity of Mesorhizobium sp. F7 Isolated from Potable Water

    Directory of Open Access Journals (Sweden)

    Pei-Ling Yong

    2014-01-01

    Full Text Available We isolated a bacterial isolate (F7 from potable water. The strain was identified as Mesorhizobium sp. by 16S rDNA gene phylogenetic analysis and screened for N-acyl homoserine lactone (AHL production by an AHL biosensor. The AHL profile of the isolate was further analyzed using high resolution triple quadrupole liquid chromatography mass spectrometry (LC/MS which confirmed the production of multiple AHLs, namely, N-3-oxo-octanoyl-L-homoserine lactone (3-oxo-C8-HSL and N-3-oxo-decanoyl-L-homoserine lactone (3-oxo-C10-HSL. These findings will open the perspective to study the function of these AHLs in plant-microbe interactions.

  13. Screening of Acetic Acid Bacteria from Pineapple Waste for Bacterial Cellulose Production using Sago Liquid Waste

    Directory of Open Access Journals (Sweden)

    Nur Arfa Yanti

    2017-12-01

    Full Text Available Bacterial cellulose is a biopolymer produced by fermentation process with the help of bacteria. It has numerous applications in industrial sector with its characteristic as a biodegradable and nontoxic compound in nature. The potential application of BC is limited by its production costs, because BC is produced from expensive culture media. The use of cheap carbon and nutrient sources such as sago liquid waste is an interesting strategy to overcome this limitation. The objective of this study was to obtain the AAB strain that capable to produce bacterial cellulose from sago liquid waste. Isolation of AAB strains was conducted using CARR media and the screening of BC production was performed on Hestrin-Schramm (HS media with glucose as a carbon source. The strains of AAB then were evaluated for their cellulose-producing capability using sago liquid waste as a substrate. Thirteen strains of AAB producing BC were isolated from pineapple waste (pineapple core and peel and seven of them were capable to produce BC using sago liquid waste substrate. One of the AAB strains produced a relatively high BC, i.e. isolate LKN6. The result of morphological and biochemical test was proven that the bacteria was Acetobacter xylinum. The result of this study showed that A. xylinum LKN6 can produce a high yield of BC, therefore this strain is potentially useful for its utilization as a starter in bacterial cellulose production. 

  14. Multi-PAS domain-mediated protein oligomerization of PpsR from Rhodobacter sphaeroides

    International Nuclear Information System (INIS)

    Heintz, Udo; Meinhart, Anton; Winkler, Andreas

    2014-01-01

    Crystal structures of two truncated variants of the transcription factor PpsR from R. sphaeroides are presented that enabled the phasing of a triple PAS domain construct. Together, these structures reveal the importance of α-helical PAS extensions for multi-PAS domain-mediated protein oligomerization and function. Per–ARNT–Sim (PAS) domains are essential modules of many multi-domain signalling proteins that mediate protein interaction and/or sense environmental stimuli. Frequently, multiple PAS domains are present within single polypeptide chains, where their interplay is required for protein function. Although many isolated PAS domain structures have been reported over the last decades, only a few structures of multi-PAS proteins are known. Therefore, the molecular mechanism of multi-PAS domain-mediated protein oligomerization and function is poorly understood. The transcription factor PpsR from Rhodobacter sphaeroides is such a multi-PAS domain protein that, in addition to its three PAS domains, contains a glutamine-rich linker and a C-terminal helix–turn–helix DNA-binding motif. Here, crystal structures of two N-terminally and C-terminally truncated PpsR variants that comprise a single (PpsR Q-PAS1 ) and two (PpsR N-Q-PAS1 ) PAS domains, respectively, are presented and the multi-step strategy required for the phasing of a triple PAS domain construct (PpsR ΔHTH ) is illustrated. While parts of the biologically relevant dimerization interface can already be observed in the two shorter constructs, the PpsR ΔHTH structure reveals how three PAS domains enable the formation of multiple oligomeric states (dimer, tetramer and octamer), highlighting that not only the PAS cores but also their α-helical extensions are essential for protein oligomerization. The results demonstrate that the long helical glutamine-rich linker of PpsR results from a direct fusion of the N-cap of the PAS1 domain with the C-terminal extension of the N-domain that plays an important

  15. Advances in liquid metal cooled ADS systems, and useful results for the design of IFMIF

    International Nuclear Information System (INIS)

    Massaut, V.; Debruyn, D.; Decreton, M.

    2007-01-01

    Full text of publication follows: Liquid metal cooled Accelerator Driven Systems (ADS) have a lot of design commonalities with the design of IFMIF. The use of a powerful accelerator and a liquid metal spallation source makes it similar to the main features of the IFMIF irradiator. Developments in the field of liquid metal ADS can thus be very useful for the design phase of IFMIF, and synergy between both domains should be enhanced to avoid dubbing work already done. The liquid metal ADS facilities are developed for testing materials under high fast (> 1 MeV) neutron flux, and also for studying the transmutation of actinides as foreseen in the P and T (Partitioning and Transmutation) strategy of future fission industry. The ADS are mostly constituted of a sub-critical fission fuel assembly matrix, a spallation source (situated at the centre of the fuel arrangement) and a powerful accelerator targeting the spallation source. In liquid metal ADS, the spallation source is a liquid metal (like Pb-Bi) which is actively cooled to remove the power generated by the particle beam, spallation reactions and neutrons. Based on an advanced ADS design (e.g. the MYRRHA/XT-ADS facility), the paper shows the various topics which are common for both facilities (ADS and IFMIF) and highlights their respective specificities, leading to focused R and D activities. This would certainly cover the common aspects related to high power accelerators, liquid metal targets and beam-target coupling. But problems of safety, radioprotection, source heating and cooling, neutrons shielding, etc... lead also to common features and developments. Results already obtained for the ADS development will illustrate this synergy. This paper will therefore allow to take profit of recent developments in both fission and fusion programs and enhance the collaboration among the R and D teams in both domains. (authors)

  16. Dimple coalescence and liquid droplets distributions during phase separation in a pure fluid under microgravity.

    Science.gov (United States)

    Oprisan, Ana; Oprisan, Sorinel A; Hegseth, John J; Garrabos, Yves; Lecoutre-Chabot, Carole; Beysens, Daniel

    2014-09-01

    Phase separation has important implications for the mechanical, thermal, and electrical properties of materials. Weightless conditions prevent buoyancy and sedimentation from affecting the dynamics of phase separation and the morphology of the domains. In our experiments, sulfur hexafluoride (SF6) was initially heated about 1K above its critical temperature under microgravity conditions and then repeatedly quenched using temperature steps, the last one being of 3.6 mK, until it crossed its critical temperature and phase-separated into gas and liquid domains. Both full view (macroscopic) and microscopic view images of the sample cell unit were analyzed to determine the changes in the distribution of liquid droplet diameters during phase separation. Previously, dimple coalescences were only observed in density-matched binary liquid mixture near its critical point of miscibility. Here we present experimental evidences in support of dimple coalescence between phase-separated liquid droplets in pure, supercritical, fluids under microgravity conditions. Although both liquid mixtures and pure fluids belong to the same universality class, both the mass transport mechanisms and their thermophysical properties are significantly different. In supercritical pure fluids the transport of heat and mass are strongly coupled by the enthalpy of condensation, whereas in liquid mixtures mass transport processes are purely diffusive. The viscosity is also much smaller in pure fluids than in liquid mixtures. For these reasons, there are large differences in the fluctuation relaxation time and hydrodynamics flows that prompted this experimental investigation. We found that the number of droplets increases rapidly during the intermediate stage of phase separation. We also found that above a cutoff diameter of about 100 microns the size distribution of droplets follows a power law with an exponent close to -2, as predicted from phenomenological considerations.

  17. Advances in liquid metal cooled ADS systems, and useful results for the design of IFMIF

    Energy Technology Data Exchange (ETDEWEB)

    Massaut, V.; Debruyn, D. [SCK CEN, Mol (Belgium); Decreton, M. [Ghent Univ., Dept. of Applied Physics (Belgium)

    2007-07-01

    Full text of publication follows: Liquid metal cooled Accelerator Driven Systems (ADS) have a lot of design commonalities with the design of IFMIF. The use of a powerful accelerator and a liquid metal spallation source makes it similar to the main features of the IFMIF irradiator. Developments in the field of liquid metal ADS can thus be very useful for the design phase of IFMIF, and synergy between both domains should be enhanced to avoid dubbing work already done. The liquid metal ADS facilities are developed for testing materials under high fast (> 1 MeV) neutron flux, and also for studying the transmutation of actinides as foreseen in the P and T (Partitioning and Transmutation) strategy of future fission industry. The ADS are mostly constituted of a sub-critical fission fuel assembly matrix, a spallation source (situated at the centre of the fuel arrangement) and a powerful accelerator targeting the spallation source. In liquid metal ADS, the spallation source is a liquid metal (like Pb-Bi) which is actively cooled to remove the power generated by the particle beam, spallation reactions and neutrons. Based on an advanced ADS design (e.g. the MYRRHA/XT-ADS facility), the paper shows the various topics which are common for both facilities (ADS and IFMIF) and highlights their respective specificities, leading to focused R and D activities. This would certainly cover the common aspects related to high power accelerators, liquid metal targets and beam-target coupling. But problems of safety, radioprotection, source heating and cooling, neutrons shielding, etc... lead also to common features and developments. Results already obtained for the ADS development will illustrate this synergy. This paper will therefore allow to take profit of recent developments in both fission and fusion programs and enhance the collaboration among the R and D teams in both domains. (authors)

  18. The BRCT domain is a phospho-protein binding domain.

    Science.gov (United States)

    Yu, Xiaochun; Chini, Claudia Christiano Silva; He, Miao; Mer, Georges; Chen, Junjie

    2003-10-24

    The carboxyl-terminal domain (BRCT) of the Breast Cancer Gene 1 (BRCA1) protein is an evolutionarily conserved module that exists in a large number of proteins from prokaryotes to eukaryotes. Although most BRCT domain-containing proteins participate in DNA-damage checkpoint or DNA-repair pathways, or both, the function of the BRCT domain is not fully understood. We show that the BRCA1 BRCT domain directly interacts with phosphorylated BRCA1-Associated Carboxyl-terminal Helicase (BACH1). This specific interaction between BRCA1 and phosphorylated BACH1 is cell cycle regulated and is required for DNA damage-induced checkpoint control during the transition from G2 to M phase of the cell cycle. Further, we show that two other BRCT domains interact with their respective physiological partners in a phosphorylation-dependent manner. Thirteen additional BRCT domains also preferentially bind phospho-peptides rather than nonphosphorylated control peptides. These data imply that the BRCT domain is a phospho-protein binding domain involved in cell cycle control.

  19. Preparation of Affinity Column Based on Zr4+ Ion for Phosphoproteins Isolation

    International Nuclear Information System (INIS)

    Lee, Seon Mi; Bae, In Ae; Park, Jung Hyen; Kim, Tae Dong; Choi, Seong Ho

    2009-01-01

    This paper has described about preparation of Zr 4+ affinity column based on the poly(styreneco- glycidyl methacrylate) prepared by emulsion polymerization of styrene and glycidyl methacrylate in order to isolate phosphopeptide. The Zr 4+ ions were introduced after the phophonation of an epoxy group on polymeric microspheres. The successful preparation of Zr 4+ -immobilized polymeric microsphere stationary phase was confirmed through Fourier transform infrared spectra, optical microscopy, scanning electron microscopy, X-ray photoelectron spectra and inductively coupled plasma-atomic emission spectrometer. The separation efficiency for Zr 4+ affinity column prepared by slurry packing was tested to phosphonated casein and dephosphonated casein. The resolution time (min) of the phosphonated casein was higher than that of dephosphated casein for Zr 4+ affinity polymeric microsphere by liquid chromatography. This Zr 4+ affinity column can be used for isolation of phosphonated casein from casein using liquid chromatography

  20. Glycoside Hydrolase (GH) 45 and 5 Candidate Cellulases in Aphelenchoides besseyi Isolated from Bird?s-Nest Fern

    OpenAIRE

    Wu, Guan-Long; Kuo, Tzu-Hao; Tsay, Tung-Tsuan; Tsai, Isheng J.; Chen, Peichen J.

    2016-01-01

    Five Aphelenchoides besseyi isolates collected from bird's-nest ferns or rice possess different parasitic capacities in bird's-nest fern. Two different glycoside hydrolase (GH) 45 genes were identified in the fern isolates, and only one was found in the rice isolates. A Abe GH5-1 gene containing an SCP-like family domain was found only in the fern isolates. Abe GH5-1 gene has five introns suggesting a eukaryotic origin. A maximum likelihood phylogeny revealed that Abe GH5-1 is part of the nem...

  1. Liquid crystal europium(III) β-diketonato complex with 5,5'-di(heptadecyl)-2,2'-bipyridine

    International Nuclear Information System (INIS)

    Knyazev, A.A.; Lobkov, V.S.; Galyametdinov, Yu.G.

    2004-01-01

    Liquid crystal europium(III) complex containing β-diketone and 5,5-di(heptadecyl)-2,2'-bipyridine as ligands was prepared in ethanol solution and was isolated as a yellow precipitate with 62% yield. The product was characterized by data of elementary analysis, thermography, IR spectroscopy and luminescence spectra. Temperatures of crystal-mesophase and mesophase-isotropic liquid phase transitions amount to 95 and 130 Deg C respectively [ru

  2. Draft Genome Sequences of Klebsiella oxytoca Isolates Originating from a Highly Contaminated Liquid Hand Soap Product.

    Science.gov (United States)

    Hammerl, J A; Lasch, P; Nitsche, A; Dabrowski, P W; Hahmann, H; Wicke, A; Kleta, S; Al Dahouk, S; Dieckmann, R

    2015-07-23

    In 2013, contaminated liquid soap was detected by routine microbiological monitoring of consumer products through state health authorities. Because of its high load of Klebsiella oxytoca, the liquid soap was notified via the European Union Rapid Alert System for Dangerous Non-Food Products (EU-RAPEX) and recalled. Here, we present two draft genome sequences and a summary of their general features. Copyright © 2015 Hammerl et al.

  3. Micro-dynamics in 2D dusty plasma liquids

    International Nuclear Information System (INIS)

    Lai, L.-J.; Teng, L.-W.; Tu, P.-S.; Chu, H.-Y.; I Lin

    2002-01-01

    We review the recent studies on the micro-dynamics in strongly coupled dust Coulomb liquids suspended in low pressure glow discharges. Under the interplay of stochastic thermal noise and Coulomb interaction, cooperative fast hopping strings and vortices excited from the small amplitude caged motion in the ordered lattice domains are the key cooperative excitations in the system. Their spatio-temporal statistical behaviors obey the similar generic power law scaling as sac type avalanche in coupled sub-excitable system under noise. The hopping can be further enhanced by the external stress and suppressed by the finite boundary. The liquid exhibits nonlinear viscoelastic response under high frequency AC shear drives and exhibits layering transition in a narrow gap down to a few molecular width. Travelling soliton-type micro-bubble can be formed through intense pulsed laser ablation

  4. Reorientation of single-wall carbon nanotubes in negative anisotropy liquid crystals by an electric field

    Directory of Open Access Journals (Sweden)

    Amanda García-García

    2016-06-01

    Full Text Available Single-wall carbon nanotubes (SWCNT are anisotropic nanoparticles that can cause modifications in the electrical and electro-optical properties of liquid crystals. The control of the SWCNT concentration, distribution and reorientation in such self-organized fluids allows for the possibility of tuning the liquid crystal properties. The alignment and reorientation of CNTs are studied in a system where the liquid crystal orientation effect has been isolated. Complementary studies including Raman spectroscopy, microscopic inspection and impedance studies were carried out. The results reveal an ordered reorientation of the CNTs induced by an electric field, which does not alter the orientation of the liquid crystal molecules. Moreover, impedance spectroscopy suggests a nonnegligible anchoring force between the CNTs and the liquid crystal molecules.

  5. Isolation of algae of the Neusa reservoir by means of cultivations in vitro

    International Nuclear Information System (INIS)

    Maldonado A; Moreno, E

    2000-01-01

    The cultivation of algae at world level is an occupation of old it dates, but in Colombia it is in its first development stages. The present work developed in the Laboratory of Bioassays, Department of Biology, National University of Colombia, is guided to contribute technical in the development of the cultivation of algae. In the practical part of the work; samples of water of the Reservoir of the Neusa were used for cultivation in liquid medium and solid medium. A better growth of filamentous cianoficeas was observed in solid medium and green algae in liquid medium. The clamidomonas is favored in both mediums, fact that allowed isolating a pure stump of this type of algae. The diatomeas for the fact of growing in connection with green algae generates a methodological problem for their isolation that is still without solving

  6. Hobi-like pestivirus: both biotypes isolated from a diseased animal.

    Science.gov (United States)

    Decaro, Nicola; Mari, Viviana; Pinto, Pierfrancesco; Lucente, Maria Stella; Sciarretta, Rossana; Cirone, Francesco; Colaianni, Maria Loredana; Elia, Gabriella; Thiel, Heinz-Jürgen; Buonavoglia, Canio

    2012-09-01

    A Hobi-like pestivirus pair consisting of cytopathogenic (cp) and non-cytopathogenic (noncp) strains, Italy 83/10cp and Italy 83/10ncp, was isolated from the lung of a heifer that died of respiratory disease. The noncp and cp viruses were isolated on Madin-Darby bovine kidney cells and separated by plaque purification and end point dilution. Analysis of the nearly full-length genomes revealed that the two viruses were very closely related to each other and to the noncp Hobi-like strain Italy 1/10-1, which had been isolated a few weeks earlier from the same herd. One major difference between noncp and cp viruses concerned the presence of a cellular Jiv sequence in the 3' domain of the NS2-encoding region of the cp strain. This is the first study, to our knowledge, reporting the isolation and molecular characterization of a Hobi-like virus pair.

  7. Transmission X-ray scattering as a probe for complex liquid-surface structures

    Energy Technology Data Exchange (ETDEWEB)

    Fukuto, Masafumi; Yang, Lin; Nykypanchuk, Dmytro; Kuzmenko, Ivan

    2016-01-28

    The need for functional materials calls for increasing complexity in self-assembly systems. As a result, the ability to probe both local structure and heterogeneities, such as phase-coexistence and domain morphologies, has become increasingly important to controlling self-assembly processes, including those at liquid surfaces. The traditional X-ray scattering methods for liquid surfaces, such as specular reflectivity and grazing-incidence diffraction, are not well suited to spatially resolving lateral heterogeneities due to large illuminated footprint. A possible alternative approach is to use scanning transmission X-ray scattering to simultaneously probe local intermolecular structures and heterogeneous domain morphologies on liquid surfaces. To test the feasibility of this approach, transmission small- and wide-angle X-ray scattering (TSAXS/TWAXS) studies of Langmuir films formed on water meniscus against a vertically immersed hydrophilic Si substrate were recently carried out. First-order diffraction rings were observed in TSAXS patterns from a monolayer of hexagonally packed gold nanoparticles and in TWAXS patterns from a monolayer of fluorinated fatty acids, both as a Langmuir monolayer on water meniscus and as a Langmuir–Blodgett monolayer on the substrate. The patterns taken at multiple spots have been analyzed to extract the shape of the meniscus surface and the ordered-monolayer coverage as a function of spot position. These results, together with continual improvement in the brightness and spot size of X-ray beams available at synchrotron facilities, support the possibility of using scanning-probe TSAXS/TWAXS to characterize heterogeneous structures at liquid surfaces.

  8. Liquid-liquid and solid-phase extractions of phenols from virgin olive oil and their separation by chromatographic and electrophoretic methods.

    Science.gov (United States)

    Bendini, Alessandra; Bonoli, Matteo; Cerretani, Lorenzo; Biguzzi, Barbara; Lercker, Giovanni; Toschi, Tullia Gallina

    2003-01-24

    The high oxidative stability of virgin olive oil is related to its high monounsaturated/polyunsaturated ratio and to the presence of antioxidant compounds, such as tocopherols and phenols. In this paper, the isolation of phenolic compounds from virgin olive oil, by different methods, was tested and discussed. Particularly liquid-liquid and solid-phase extraction methods were compared, assaying, for the latter, three stationary phases (C8, C18 and Diol) and several elution mixtures. Quantification of phenolic and o-diphenolic substances in the extracts was performed by the traditional Folin-Ciocalteau method and the sodium molybdate reaction, respectively. Furthermore, the quantification of phenolic compounds in the extracts and in a standard mixture was carried out both with diode array and mass spectrometric detection and capillary zone electrophoresis.

  9. Landau–De Gennes Theory of Nematic Liquid Crystals: the Oseen–Frank Limit and Beyond

    KAUST Repository

    Majumdar, Apala

    2009-07-07

    We study global minimizers of a continuum Landau-De Gennes energy functional for nematic liquid crystals, in three-dimensional domains, subject to uniaxial boundary conditions. We analyze the physically relevant limit of small elastic constant and show that global minimizers converge strongly, in W1,2, to a global minimizer predicted by the Oseen-Frank theory for uniaxial nematic liquid crystals with constant order parameter. Moreover, the convergence is uniform in the interior of the domain, away from the singularities of the limiting Oseen-Frank global minimizer. We obtain results on the rate of convergence of the eigenvalues and the regularity of the eigenvectors of the Landau-De Gennes global minimizer. We also study the interplay between biaxiality and uniaxiality in Landau-De Gennes global energy minimizers and obtain estimates for various related quantities such as the biaxiality parameter and the size of admissible strongly biaxial regions. © Springer-Verlag (2009).

  10. Landau–De Gennes Theory of Nematic Liquid Crystals: the Oseen–Frank Limit and Beyond

    KAUST Repository

    Majumdar, Apala; Zarnescu, Arghir

    2009-01-01

    We study global minimizers of a continuum Landau-De Gennes energy functional for nematic liquid crystals, in three-dimensional domains, subject to uniaxial boundary conditions. We analyze the physically relevant limit of small elastic constant and show that global minimizers converge strongly, in W1,2, to a global minimizer predicted by the Oseen-Frank theory for uniaxial nematic liquid crystals with constant order parameter. Moreover, the convergence is uniform in the interior of the domain, away from the singularities of the limiting Oseen-Frank global minimizer. We obtain results on the rate of convergence of the eigenvalues and the regularity of the eigenvectors of the Landau-De Gennes global minimizer. We also study the interplay between biaxiality and uniaxiality in Landau-De Gennes global energy minimizers and obtain estimates for various related quantities such as the biaxiality parameter and the size of admissible strongly biaxial regions. © Springer-Verlag (2009).

  11. Isolation of oxidative degradation products of atorvastatin with supercritical fluid chromatography.

    Science.gov (United States)

    Klobčar, Slavko; Prosen, Helena

    2015-12-01

    The isolation of four oxidative degradation products of atorvastatin using preparative high-performance liquid chromatography applying at least two chromatographic steps is known from the literature. In this paper it is shown that the same four impurities could be isolated from similarly prepared mixtures in only one step using supercritical fluid chromatography. The methods for separation were developed and optimized. The preparation of the mixtures was altered in such a way as to enhance the concentration of desired impurities. Appropriate solvents were applied for collection of separated impurities in order to prevent degradation. The structures of the isolated impurities were confirmed and their purity determined. The preparative supercritical fluid chromatography has proven to be superior to preparative HPLC regarding achieved purity of standards applying fewer chromatographic as well as isolation steps. Copyright © 2015 John Wiley & Sons, Ltd.

  12. Dynamical thermalization in isolated quantum dots and black holes

    Science.gov (United States)

    Kolovsky, Andrey R.; Shepelyansky, Dima L.

    2017-01-01

    We study numerically a model of quantum dot with interacting fermions. At strong interactions with small conductance the model is reduced to the Sachdev-Ye-Kitaev black-hole model while at weak interactions and large conductance it describes a Landau-Fermi liquid in a regime of quantum chaos. We show that above the Åberg threshold for interactions there is an onset of dynamical themalization with the Fermi-Dirac distribution describing the eigenstates of an isolated dot. At strong interactions in the isolated black-hole regime there is also the onset of dynamical thermalization with the entropy described by the quantum Gibbs distribution. This dynamical thermalization takes place in an isolated system without any contact with a thermostat. We discuss the possible realization of these regimes with quantum dots of 2D electrons and cold ions in optical lattices.

  13. Bacterial elongation factors EF-Tu, their mutants, chimeric forms, and domains: isolation and purification

    Czech Academy of Sciences Publication Activity Database

    Jonák, Jiří

    2007-01-01

    Roč. 849, 1-2 (2007), s. 141-153 ISSN 1570-0232 R&D Projects: GA AV ČR IAA5052206; GA AV ČR KJB500520503; GA MŠk 2B06065 Institutional research plan: CEZ:AV0Z50520514 Keywords : bacterial elongation factors EF-Tu, , G-domain * recombinant EF-Tus * preparation Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.935, year: 2007

  14. Partial liquid-penetration inside a deep trench by film flowing over it

    Science.gov (United States)

    Nguyen, Phuc-Khanh; Dimakopoulos, Yiannis; Tsamopoulos, John

    2014-11-01

    Liquid film flow along substrates featuring a deep trench may not wet the trench floor, but create a second gas-liquid interface inside the trench. The liquid penetration inside the trench depends on the location and shape of this inner interface. The penetration increases by decreasing the two three-phase contact lines between the inner interface and the two side-walls or the flow rate and depends on the liquid properties. This partial-penetration is studied by employing the Galerkin / finite element method to solve the two-dimensional steady-state Navier-Stokes equations in a physical domain that is adaptively remeshed. Multiple branches of steady solutions connected via turning points are revealed by pseudo arc-length continuation. Flow hysteresis may occur in a certain range of liquid penetration depth, when the interaction of the two interfaces changes qualitatively. This induces an abrupt jump of penetration distance and deformation amplitude of the outer interface. Work supported by the General Secretariat of Research & Technology of Greece through the program ``Excellence'' (Grant No. 1918) in the framework ``Education and Lifelong Learning'' co-funded by the ESF.

  15. Domain analysis

    DEFF Research Database (Denmark)

    Hjørland, Birger

    2017-01-01

    The domain-analytic approach to knowledge organization (KO) (and to the broader field of library and information science, LIS) is outlined. The article reviews the discussions and proposals on the definition of domains, and provides an example of a domain-analytic study in the field of art studies....... Varieties of domain analysis as well as criticism and controversies are presented and discussed....

  16. Real-space imaging of fractional quantum Hall liquids

    Science.gov (United States)

    Hayakawa, Junichiro; Muraki, Koji; Yusa, Go

    2013-01-01

    Electrons in semiconductors usually behave like a gas--as independent particles. However, when confined to two dimensions under a perpendicular magnetic field at low temperatures, they condense into an incompressible quantum liquid. This phenomenon, known as the fractional quantum Hall (FQH) effect, is a quantum-mechanical manifestation of the macroscopic behaviour of correlated electrons that arises when the Landau-level filling factor is a rational fraction. However, the diverse microscopic interactions responsible for its emergence have been hidden by its universality and macroscopic nature. Here, we report real-space imaging of FQH liquids, achieved with polarization-sensitive scanning optical microscopy using trions (charged excitons) as a local probe for electron spin polarization. When the FQH ground state is spin-polarized, the triplet/singlet intensity map exhibits a spatial pattern that mirrors the intrinsic disorder potential, which is interpreted as a mapping of compressible and incompressible electron liquids. In contrast, when FQH ground states with different spin polarization coexist, domain structures with spontaneous quasi-long-range order emerge, which can be reproduced remarkably well from the disorder patterns using a two-dimensional random-field Ising model. Our results constitute the first reported real-space observation of quantum liquids in a class of broken symmetry state known as the quantum Hall ferromagnet.

  17. Inferring domain-domain interactions from protein-protein interactions with formal concept analysis.

    Directory of Open Access Journals (Sweden)

    Susan Khor

    Full Text Available Identifying reliable domain-domain interactions will increase our ability to predict novel protein-protein interactions, to unravel interactions in protein complexes, and thus gain more information about the function and behavior of genes. One of the challenges of identifying reliable domain-domain interactions is domain promiscuity. Promiscuous domains are domains that can occur in many domain architectures and are therefore found in many proteins. This becomes a problem for a method where the score of a domain-pair is the ratio between observed and expected frequencies because the protein-protein interaction network is sparse. As such, many protein-pairs will be non-interacting and domain-pairs with promiscuous domains will be penalized. This domain promiscuity challenge to the problem of inferring reliable domain-domain interactions from protein-protein interactions has been recognized, and a number of work-arounds have been proposed. This paper reports on an application of Formal Concept Analysis to this problem. It is found that the relationship between formal concepts provides a natural way for rare domains to elevate the rank of promiscuous domain-pairs and enrich highly ranked domain-pairs with reliable domain-domain interactions. This piggybacking of promiscuous domain-pairs onto less promiscuous domain-pairs is possible only with concept lattices whose attribute-labels are not reduced and is enhanced by the presence of proteins that comprise both promiscuous and rare domains.

  18. Inferring Domain-Domain Interactions from Protein-Protein Interactions with Formal Concept Analysis

    Science.gov (United States)

    Khor, Susan

    2014-01-01

    Identifying reliable domain-domain interactions will increase our ability to predict novel protein-protein interactions, to unravel interactions in protein complexes, and thus gain more information about the function and behavior of genes. One of the challenges of identifying reliable domain-domain interactions is domain promiscuity. Promiscuous domains are domains that can occur in many domain architectures and are therefore found in many proteins. This becomes a problem for a method where the score of a domain-pair is the ratio between observed and expected frequencies because the protein-protein interaction network is sparse. As such, many protein-pairs will be non-interacting and domain-pairs with promiscuous domains will be penalized. This domain promiscuity challenge to the problem of inferring reliable domain-domain interactions from protein-protein interactions has been recognized, and a number of work-arounds have been proposed. This paper reports on an application of Formal Concept Analysis to this problem. It is found that the relationship between formal concepts provides a natural way for rare domains to elevate the rank of promiscuous domain-pairs and enrich highly ranked domain-pairs with reliable domain-domain interactions. This piggybacking of promiscuous domain-pairs onto less promiscuous domain-pairs is possible only with concept lattices whose attribute-labels are not reduced and is enhanced by the presence of proteins that comprise both promiscuous and rare domains. PMID:24586450

  19. Hydrogen bonding discotic liquid crystals: Synthesis, self-assembly, and molecular recognition

    Science.gov (United States)

    Bushey, Mark Lawrence

    The triamides shown below form discotic liquid crystalline phases with intermolecular hydrogen bonding stabilizing the columnar structure, A and B. The mesomorphic orientations of the columns are dependent on the amide side chain. Three mesophasic orientations are described: columns aligned perpendicular to the surface, columns aligned parallel to the surface in a radial pattern, and columns aligned parallel to the surface in a parallel or aligned pattern. The aggregation of the tridodecyloxy-triamides show N-H shifting in the IR at elevated temperatures, an indication that hydrogen bonding is important in the association of liquid crystalline mesophases. Powder X-ray diffraction studies indicate packing of the columns into a hexagonal lattice.* Studies on triamides with chiral side chains result in molecules stacking into columns displaying a helical pitch. In concentrated solutions of dodecane, molecules with chiral side chains display behavior consistent with chiral nematic liquid crystals; a super helical packing of the chiral columns. These superhelical packed systems show temperature dependent selective reflection of visible light and fingerprint textures. Atomic force microscopy (AFM) confirms in sub-monolayer films, that molecules preferring an edge-on orientation form long columns on highly ordered pyrolytic graphite (HOPG), those that prefer a face-on orientation form large amorphous domains. Electrostatic force microscopy (EFM) images of the domains of molecules in the edge-on orientation provides no discernible polarity, imaging of the domains of molecules in the face-on orientation indicates a negative polar orientation. Scanning probe measurements (SPM) of the tridodecynyl-triamide have shown similar edge-on orientations of other tridodecyloxy-triamides. Powder X-ray diffraction of these liquid crystalline phases shows a hexagonal packing of the columnar assembly. Electro-optic switching studies indicate a piezoelectric switching mechanism, possibly

  20. Crystal structure of glucagon-like peptide-1 in complex with the extracellular domain of the glucagon-like peptide-1 receptor.

    Science.gov (United States)

    Underwood, Christina Rye; Garibay, Patrick; Knudsen, Lotte Bjerre; Hastrup, Sven; Peters, Günther H; Rudolph, Rainer; Reedtz-Runge, Steffen

    2010-01-01

    GLP-1 (glucagon-like peptide-1) is an incretin released from intestinal L-cells in response to food intake. Activation of the GLP-1 receptor potentiates the synthesis and release of insulin from pancreatic beta-cells in a glucose-dependent manner. The GLP-1 receptor belongs to class B of the G-protein-coupled receptors, a subfamily characterized by a large N-terminal extracellular ligand binding domain. Exendin-4 and GLP-1 are 50% identical, and exendin-4 is a full agonist with similar affinity and potency for the GLP-1 receptor. We recently solved the crystal structure of the GLP-1 receptor extracellular domain in complex with the competitive antagonist exendin-4(9-39). Interestingly, the isolated extracellular domain binds exendin-4 with much higher affinity than the endogenous agonist GLP-1. Here, we have solved the crystal structure of the extracellular domain in complex with GLP-1 to 2.1 Aresolution. The structure shows that important hydrophobic ligand-receptor interactions are conserved in agonist- and antagonist-bound forms of the extracellular domain, but certain residues in the ligand-binding site adopt a GLP-1-specific conformation. GLP-1 is a kinked but continuous alpha-helix from Thr(13) to Val(33) when bound to the extracellular domain. We supplemented the crystal structure with site-directed mutagenesis to link the structural information of the isolated extracellular domain with the binding properties of the full-length receptor. The data support the existence of differences in the binding modes of GLP-1 and exendin-4 on the full-length GLP-1 receptor.

  1. Sequence and Secondary Structure of the Mitochondrial Small-Subunit rRNA V4, V6, and V9 Domains Reveal Highly Species-Specific Variations within the Genus Agrocybe

    OpenAIRE

    Gonzalez, Patrice; Labarère, Jacques

    1998-01-01

    A comparative study of variable domains V4, V6, and V9 of the mitochondrial small-subunit (SSU) rRNA was carried out with the genus Agrocybe by PCR amplification of 42 wild isolates belonging to 10 species, Agrocybe aegerita, Agrocybe dura, Agrocybe chaxingu, Agrocybe erebia, Agrocybe firma, Agrocybe praecox, Agrocybe paludosa, Agrocybe pediades, Agrocybe alnetorum, and Agrocybe vervacti. Sequencing of the PCR products showed that the three domains in the isolates belonging to the same specie...

  2. Phosphatidylinositol 3,5-Bisphosphate-Rich Membrane Domains in Endosomes and Lysosomes.

    Science.gov (United States)

    Takatori, Sho; Tatematsu, Tsuyako; Cheng, Jinglei; Matsumoto, Jun; Akano, Takuya; Fujimoto, Toyoshi

    2016-02-01

    Phosphatidylinositol 3,5-bisphosphate (PtdIns(3,5)P2 ) has critical functions in endosomes and lysosomes. We developed a method to define nanoscale distribution of PtdIns(3,5)P2 using freeze-fracture electron microscopy. GST-ATG18-4×FLAG was used to label PtdIns(3,5)P2 and its binding to phosphatidylinositol 3-phosphate (PtdIns(3)P) was blocked by an excess of the p40(phox) PX domain. In yeast exposed to hyperosmotic stress, PtdIns(3,5)P2 was concentrated in intramembrane particle (IMP)-deficient domains in the vacuolar membrane, which made close contact with adjacent membranes. The IMP-deficient domain was also enriched with PtdIns(3)P, but was deficient in Vph1p, a liquid-disordered domain marker. In yeast lacking either PtdIns(3,5)P2 or its effector, Atg18p, the IMP-deficient, PtdIns(3)P-rich membranes were folded tightly to make abnormal tubular structures, thus showing where the vacuolar fragmentation process is arrested when PtdIns(3,5)P2 metabolism is defective. In HeLa cells, PtdIns(3,5)P2 was significantly enriched in the vesicular domain of RAB5- and RAB7-positive endosome/lysosomes of the tubulo-vesicular morphology. This biased distribution of PtdIns(3,5)P2 was also observed using fluorescence microscopy, which further showed enrichment of a retromer component, VPS35, in the tubular domain. This is the first report to show segregation of PtdIns(3,5)P2 -rich and -deficient domains in endosome/lysosomes, which should be important for endosome/lysosome functionality. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Beam-splitter switches based on zenithal bistable liquid-crystal gratings.

    Science.gov (United States)

    Zografopoulos, Dimitrios C; Beccherelli, Romeo; Kriezis, Emmanouil E

    2014-10-01

    The tunable optical diffractive properties of zenithal bistable nematic liquid-crystal gratings are theoretically investigated. The liquid-crystal orientation is rigorously solved via a tensorial formulation of the Landau-de Gennes theory and the optical transmission properties of the gratings are investigated via full-wave finite-element frequency-domain simulations. It is demonstrated that by proper design the two stable states of the grating can provide nondiffracting and diffracting operation, the latter with equal power splitting among different diffraction orders. An electro-optic switching mechanism, based on dual-frequency nematic materials, and its temporal dynamics are further discussed. Such gratings provide a solution towards tunable beam-steering and beam-splitting components with extremely low power consumption.

  4. Interaction of the transactivation domain of B-Myb with the TAZ2 domain of the coactivator p300: molecular features and properties of the complex.

    Directory of Open Access Journals (Sweden)

    Ojore Oka

    Full Text Available The transcription factor B-Myb is a key regulator of the cell cycle in vertebrates, with activation of transcription involving the recognition of specific DNA target sites and the recruitment of functional partner proteins, including the coactivators p300 and CBP. Here we report the results of detailed studies of the interaction between the transactivation domain of B-Myb (B-Myb TAD and the TAZ2 domain of p300. The B-Myb TAD was characterized using circular dichroism, fluorescence and NMR spectroscopy, which revealed that the isolated domain exists as a random coil polypeptide. Pull-down and spectroscopic experiments clearly showed that the B-Myb TAD binds to p300 TAZ2 to form a moderately tight (K(d ~1.0-10 µM complex, which results in at least partial folding of the B-Myb TAD. Significant changes in NMR spectra of p300 TAZ2 suggest that the B-Myb TAD binds to a relatively large patch on the surface of the domain (~1200 Å(2. The apparent B-Myb TAD binding site on p300 TAZ2 shows striking similarity to the surface of CBP TAZ2 involved in binding to the transactivation domain of the transcription factor signal transducer and activator of transcription 1 (STAT1, which suggests that the structure of the B-Myb TAD-p300 TAZ2 complex may share many features with that reported for STAT1 TAD-p300 TAZ2.

  5. Use of scintillometric quantitation of unscheduled DNA synthesis in isolated rat hepatocytes for the screening of genotoxic agents

    International Nuclear Information System (INIS)

    Hsia, M.T.

    1987-01-01

    The induction of unscheduled DNA synthesis has been considered as a suitable endpoint for the screening of genotoxic agents. Experimentally, unscheduled DNA synthesis is most frequently measured by autoradiography. The purpose of this report was to examine the usefulness of the liquid scintillation counting technique in measuring unscheduled DNA synthesis response in isolated rat hepatocytes. The various liquid scintillation counting-based unscheduled DNA synthesis assay procedures were examined according to the following groupings: (1) procedures based on the acid precipitation of cellular macromolecules, (2) procedures based on isopycnic gradient centrifugation of solubilized cells, (3) procedures based on nuclei isolation in conjunction with other DNA purification methods, and (4) procedures based on the selective retention of hepatocellular DNA. Limited cases in which test chemicals gave positive unscheduled DNA synthesis response in liquid scintillation counting-based assays and negative unscheduled DNA synthesis response in autoradiography-based assays are presented. It is concluded that liquid scintillation counting-based unscheduled DNA synthesis assays represent an appropriate system for inclusion in carcinogenicity and mutagenicity testing programs

  6. Extended Smoluchowski models for interpreting relaxation phenomena in liquids

    International Nuclear Information System (INIS)

    Polimeno, A.; Frezzato, D.; Saielli, G.; Moro, G.J.; Nordio, P.L.

    1998-01-01

    Interpretation of the dynamical behaviour of single molecules or collective modes in liquids has been increasingly centered, in the last decade, on complex liquid systems, including ionic solutions, polymeric liquids, supercooled fluids and liquid crystals. This has been made necessary by the need of interpreting dynamical data obtained by advanced experiments, like optical Kerr effect, time dependent fluorescence shift experiments, two-dimensional Fourier-transform and high field electron spin resonance and scattering experiments like quasi-elastic neutron scattering. This communication is centered on the definition, treatment and application of several extended stochastic models, which have proved to be very effective tools for interpreting and rationalizing complex relaxation phenomena in liquids structures. First, applications of standard Fokker-Planck equations for the orientational relaxation of molecules in isotropic and ordered liquid phase are reviewed. In particular attention will be focused on the interpretation of neutron scattering in nematics. Next, an extended stochastic model is used to interpret time-domain resolved fluorescence emission experiments. A two-body stochastic model allows the theoretical interpretation of dynamical Stokes shift effects in fluorescence emission spectra, performed on probes in isotropic and ordered polar phases. Finally, for the case of isotropic fluids made of small rigid molecules, a very detailed model is considered, which includes as basic ingredients a Fokker-Planck description of the molecular vibrational motion and the slow diffusive motion of a persistent cage structure together with the decay processes related to the changing structure of the cage. (author)

  7. Detection, isolation and characterization of principle synthetic route indicative impurity in telmisartan

    Directory of Open Access Journals (Sweden)

    V. Srinivasan

    2016-11-01

    Full Text Available An unknown impurity was detected in the telmisartan bulk drug (active pharmaceutical ingredient – API using an isocratic reversed-phase high performance liquid chromatography (HPLC. This impurity was isolated by preparative HPLC. Spectral data of the isolated impurity were collected. Based on the spectral data deriving from two dimensional nuclear magnetic spectroscopy (2D-NMR and mass spectrometry (MS, the impurity was characterized as “methyl 4′,4′-dibromo methyl biphenyl-2-carboxylate”. The arrived structure was further confirmed by theoretical studies.

  8. Optical properties of quantum-dot-doped liquid scintillators

    International Nuclear Information System (INIS)

    Aberle, C; Winslow, L; Li, J J; Weiss, S

    2013-01-01

    Semiconductor nanoparticles (quantum dots) were studied in the context of liquid scintillator development for upcoming neutrino experiments. The unique optical and chemical properties of quantum dots are particularly promising for the use in neutrinoless double-beta decay experiments. Liquid scintillators for large scale neutrino detectors have to meet specific requirements which are reviewed, highlighting the peculiarities of quantum-dot-doping. In this paper, we report results on laboratory-scale measurements of the attenuation length and the fluorescence properties of three commercial quantum dot samples. The results include absorbance and emission stability measurements, improvement in transparency due to filtering of the quantum dot samples, precipitation tests to isolate the quantum dots from solution and energy transfer studies with quantum dots and the fluorophore PPO

  9. Serological characterisation of foot-and-mouth disease type 'O' field isolates from Peru: 1992-1994

    International Nuclear Information System (INIS)

    Espinoza, A.M.

    1998-01-01

    Nineteen field isolates of foot-and-mouth disease Virus (FMDV) recovered from bovine epithelial samples corresponding to outbreaks present in different regions of Peru, between 1992-1994 were studied. The relationship of the virus isolates to the O/Urubamba vaccine strain of Peru was determined by the calculation of the 'r' values obtained by the liquid-phase blocking ELISA. All the isolates showed 'r' values higher than 0.66 indicating that the vaccine strain should protect against the field strains. Characterization of the field isolates by a trapping ELISA using a panel of monoclonal antibodies against FMDV O/Switzerland and O/Caseros, showed slight differences in the profiles of the field isolates when compared with the O/Urubamba vaccine strain, but no differences were found among all the isolates. (author)

  10. Analysis of Nitro-aromatic and Nitramine Explosives by Atmospheric Pressure Chemical Ionization / High Performance Liquid Chromatography / Mass Spectrometry / Mass Spectrometry

    International Nuclear Information System (INIS)

    Hicks, B.J.; Han, W.; Robben, J.R.

    2009-01-01

    This procedure is capable of separating and quantifying twenty-nine high explosives and internal surrogates with a single injection. After the initial preparation step, the sample is introduced to the high performance liquid chromatograph for target separation, ionized by atmospheric pressure chemical ionization and the explosives of interest are isolated / quantified by mass spectrometry / mass spectrometry. Concentrations of the target explosives are measured relative to the response of both internal and external standard concentrations. A C-18 reverse phase high performance liquid chromatograph column is used for separation. Ionization is performed using both positive and negative atmospheric pressure chemical ionization resulting in a molecular ion with little fragmentation. These ions are isolated at the first quadrupole of the mass spectrometer, dissociated by collision with argon in the collision cell and the resulting daughter ions are isolated at the second quadrupole. These daughter ions then reach the detector where they are quantified. To date this procedure represents the most thorough high performance liquid chromatography / mass spectrometry / mass spectrometry explosives analysis available in the environmental chemistry market. (authors)

  11. Technical specifications for the successful fabrication of laminated seismic isolation bearings

    International Nuclear Information System (INIS)

    Kulak, R.F.

    1992-01-01

    High damping steel-laminated elastomeric seismic isolation bearings are becoming a preferred device for isolating large buildings and structures. In the United States, the current reference design for the Advanced Liquid Metal Reactor uses laminated bearings for seismic isolation. These bearings are constructed from alternating layers of rubber and steel plates. They are typically designed for shear strains between 50 to 100 percent and expected to sustain two to three times these levels for beyond design basis loading considerations. The technical specifications used to procure these bearings are an important factor in assuring that the bearings meet the performance requirements of the design. The key aspects of the current version of the Technical Specifications are discussed in this paper. (author)

  12. A model Apparatus for Isolation of Volatile Oils from Various Plant Materials

    Directory of Open Access Journals (Sweden)

    Mahdi T. AI-Kaisey

    2018-02-01

    The present paper givas a detailed description of apparatus which were sutable for isola.tion the lighter and tile heavier u.('-m water volatile oils fronl differenet plant materials. Meanwhile tbe purity of tile concentrates were ex lrined by g-aS liquid chromato graphy( GLe.

  13. Llama-Derived Single Domain Antibodies Specific for Abrus Agglutinin

    Science.gov (United States)

    Goldman, Ellen R.; Anderson, George P.; Zabetakis, Dan; Walper, Scott; Liu, Jinny L.; Bernstein, Rachael; Calm, Alena; Carney, James P.; O’Brien, Thomas W.; Walker, Jennifer L.; Garber, Eric A. E.

    2011-01-01

    Llama derived single domain antibodies (sdAb), the recombinantly expressed variable heavy domains from the unique heavy-chain only antibodies of camelids, were isolated from a library derived from llamas immunized with a commercial abrin toxoid preparation. Abrin is a potent toxin similar to ricin in structure, sequence and mechanism of action. The selected sdAb were evaluated for their ability to bind to commercial abrin as well as abrax (a recombinant abrin A-chain), purified abrin fractions, Abrus agglutinin (a protein related to abrin but with lower toxicity), ricin, and unrelated proteins. Isolated sdAb were also evaluated for their ability to refold after heat denaturation and ability to be used in sandwich assays as both capture and reporter elements. The best binders were specific for the Abrus agglutinin, showing minimal binding to purified abrin fractions or unrelated proteins. These binders had sub nM affinities and regained most of their secondary structure after heating to 95 °C. They functioned well in sandwich assays. Through gel analysis and the behavior of anti-abrin monoclonal antibodies, we determined that the commercial toxoid preparation used for the original immunizations contained a high percentage of Abrus agglutinin, explaining the selection of Abrus agglutinin binders. Used in conjunction with anti-abrin monoclonal and polyclonal antibodies, these reagents can fill a role to discriminate between the highly toxic abrin and the related, but much less toxic, Abrus agglutinin and distinguish between different crude preparations. PMID:22174977

  14. Vulnerability and floor spectra of seismically isolated structures

    International Nuclear Information System (INIS)

    Pham, K.H.

    2010-09-01

    This thesis was motivated by issues that arise regarding the use of the method of seismic isolation in the nuclear industry. Despite the research conducted during the last decades in the field of seismic isolation, many questions about the behavior of isolated structures remain. These questions concern, on the one hand, the vulnerability of these structures, due to an excursion (unexpected) in the post-linear domain, and on the other hand, phenomena that can lead to a significant excitation of none isolated modes. Furthermore, unlike previous work studying the seismic behavior of buildings, an important part of this thesis is devoted to the behavior of equipment through the study of floor spectra. Firstly, the probability of failure, in the case of nonlinear response of the superstructure, was studied with simple models, for different laws of nonlinear behavior and different types of support. Then, the effects of heavy damping were investigated and the mechanism of amplification of the response of non-isolated modes has been explained. To resolve the amplification problem of none isolated modes, the mixed isolated systems, combining passive isolation with semi-active devices, have been considered. The numerical analyses confirm the effectiveness of this approach. Finally, a series of shaking table tests on a simple model with two degrees of freedom was conducted. The model is equipped with a magneto-rheological damper which is controlled as a semi-active device. The comparison of the experimental results with those of numerical simulations shows that the models developed are able to represent satisfactorily the essential physical phenomena. (author)

  15. Distributed Fracturing Affecting the Isolated Carbonate Platforms, the Latemar Platform (Dolomites, North Italy).

    NARCIS (Netherlands)

    Boro, H.; Bertotti, G.V.; Hardebol, N.J.

    2012-01-01

    Isolated carbonate platforms are highly heterogeneous bodies and are typically composed of laterally juxtaposed first order domains with different sedimentological composition and organization, i.e. a well-stratified platform interior, a massive margin and a slope with steeply dipping and poorly

  16. Domain growth of carbon nanotubes assisted by dewetting of thin catalyst precursor films

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, Alok Kumar [Defence Materials and Stores R and D Establishment (DRDO), GT Road, Kanpur 208013 (India); Department of Chemical Engineering, Indian Institute of Technology, Kanpur 208016 (India); Sachan, Priyanka; Samanta, Chandan [Department of Chemical Engineering, Indian Institute of Technology, Kanpur 208016 (India); Mukhopadhyay, Kingsuk [Defence Materials and Stores R and D Establishment (DRDO), GT Road, Kanpur 208013 (India); Sharma, Ashutosh, E-mail: ashutos@iitk.ac.in [Department of Chemical Engineering, Indian Institute of Technology, Kanpur 208016 (India)

    2014-01-01

    We explore self-organized dewetting of ultrathin films of a novel metal complex as a one step surface patterning method to create nanoislands of iron, using which spatially separated carbon nanostructures were synthesized. Dewetting of ultrathin metal complex films was induced by two different methods: liquid solvent exposure and thermal annealing to engender surface patterning. For thermal dewetting, thin films of the iron oleate complex were dewetted at high temperature. In the case of liquid solvent assisted dewetting, the metal complex, mixed with a sacrificial polymer (polystyrene) was spin coated as thin films (<40 nm) and then dewetted under an optimal solution mixture consisting of methyl ethyl ketone, acetone and water. The carrier polymer was then selectively removed to produce the iron metal islands. These metal islands were used for selective growth of discrete patches of multiwall CNTs and CNFs by a chemical vapor deposition (CVD) process. Solvent induced dewetting showed clear advantages over thermal dewetting owing to reduced size of catalyst domains formed by dewetting, an improved control over CNT growth as well as in its ability to immobilize the seed particles. The generic solution mediated dewetting and pattern generation in thin films of various catalytic precursors can thus be a powerful method for selective domain growth of a variety of functional nanomaterials.

  17. Comparison of SH3 and SH2 domain dynamics when expressed alone or in an SH(3+2) construct: the role of protein dynamics in functional regulation.

    Science.gov (United States)

    Engen, J R; Smithgall, T E; Gmeiner, W H; Smith, D L

    1999-04-02

    Protein dynamics play an important role in protein function and regulation of enzymatic activity. To determine how additional interactions with surrounding structure affects local protein dynamics, we have used hydrogen exchange and mass spectrometry to investigate the SH2 and SH3 domains of the protein tyrosine kinase Hck. Exchange rates of isolated Hck SH3 and SH2 domains were compared with rates for the same domains when part of a larger SH(3+2) construct. Increased deuterium incorporation was observed for the SH3 domain in the joint construct, particularly near the SH2 interface and the short sequence that connects SH3 to SH2, implying greater flexibility of SH3 when it is part of SH(3+2). Slow cooperative unfolding of the SH3 domain occurred at the same rate in isolated SH3 as in the SH(3+2) construct, suggesting a functional significance for this unfolding. The SH2 domain displayed relatively smaller changes in flexibility when part of the SH(3+2) construct. These results suggest that the domains influence each other. Further, our results imply a link between functional regulation and structural dynamics of SH3 and SH2 domains. Copyright 1999 Academic Press.

  18. Quantitative Analysis of Piroxicam Using Temperature-Controlled Ionic Liquid Dispersive Liquid Phase Microextraction Followed By Stopped-Flow Injection Spectrofluorimetry

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Ganjali

    2013-07-01

    Full Text Available Background:Piroxicam (PXM belongs to the wide class of non-steroidal anti-inflammatory drugs (NSAIDs. PXM has been widely applied in the treatment of rheumatoid arthritis, gonarthrosis, osteoarthritis, backaches, neuralgia, mialgia. In the presented work, a green and benign sample pretreatment method called temperature-controlled ionic liquid dispersive liquid phase microextraction (TCIL-DLPME was followed with stopped-flow injection spectrofluorimetry (SFIS for quantitation of PXM in pharmaceutical formulations and biological samples.Methods:Temperature-controlled ionic liquid dispersive liquid phase microextraction (TCIL-DLPME was applied as an environmentally friendly sample enrichment method to extract and isolate PXM prior to quantitation. Dispersion of 1-hexyl-3-methylimidazolium hexafluorophosphate ([Hmim][PF6] ionic liquid (IL through the sample aqueous solution was performed by applying a relatively high temperature. PXM was extracted into the extractor, and after phase separation, PXM in the final solution was determined by stopped-flow injection spectrofluorimetry (SFIS.Results and Major Conclusion:Different factors affecting the designed method such as IL amount, diluting agent, pH and temperature were investigated in details and optimized. The method provided a linear dynamic range of 0.2-150 μg l-1, a limit of detection (LOD of 0.046 μg l-1 and a relative standard deviation (RSD of 3.1%. Furthermore, in order to demonstrate the analytical applicability of the recommended method, it was applied for quantitation of PXM in real samples.

  19. The Effectivity of Marine Bio-activator and Surimi Liquid Waste Addition of Characteristics Liquid Organic Fertilizer from Sargassum sp.

    Directory of Open Access Journals (Sweden)

    Putri Wening Ratrinia

    2017-02-01

    Full Text Available AbstractOrganic fertilizer is highly recommended for soil and plant because it can improve the productivity and repair physical, chemical, and biological of soil. Sargassum sp. and surimi liquid wastes contain organic matter and nutrient needed by plants and soils. The addition of marine bio-activator which contains bacterial isolates from litter mangrove serves to accelerate the composting time and increases the activity of microorganisms in the decomposition process. The purpose of this study was to determine optimum time and the best formulation of decomposition process organic fertilizer. Raw materials used a waste of seaweed Sargassum sp., marine bio-activator and surimi liquid waste from catfish (Clarias sp.. The research was conducted six treatments control, Sargassum sp. + marine bio-activator, surimi liquid waste , Sargassum sp. + marine bio-activator + surimi liquid waste 80%, 90%, 100%. All treatments were fermented for 9 days and analysed the C-organic, total N, C/N ratio, P2O5, K2O on days 0, 3, 6 and 9. The results showed the optimum fermentation period was on the 6th day. The most optimum concentration of surimi liquid waste added was at a concentration of 90%, with characteristics of the products was C-organic 0.803±0.0115%, total N 740.063±0.0862 ppm, C/N ratio 10.855±0.1562, P2O5 425.603±0.2329 ppm, K2O 2738.627±0.2836 ppm.

  20. The Effectivity of Marine Bio-activator and Surimi Liquid Waste Addition of Characteristics Liquid Organic Fertilizer from Sargassum sp.

    Directory of Open Access Journals (Sweden)

    Putri Wening Ratrinia

    2016-12-01

    Full Text Available Organic fertilizer is highly recommended for soil and plant because it can improve the productivity and repair physical, chemical, and biological of soil. Sargassum sp. and surimi liquid wastes contain organic matter and nutrient needed by plants and soils. The addition of marine bio-activator which contains bacterial isolates from litter mangrove serves to accelerate the composting time and increases the activity of microorganisms in the decomposition process. The purpose of this study was to determine optimum time and the best formulation of decomposition process organic fertilizer. Raw materials used a waste of seaweed Sargassum sp., marine bio-activator and surimi liquid waste from catfish (Clarias sp.. The research was conducted six treatments control, Sargassum sp. + marine bio-activator, surimi liquid waste , Sargassum sp. + marine bio-activator + surimi liquid waste 80%, 90%, 100%. All treatments were fermented for 9 days and analysed the C-organic, total N, C/N ratio, P2 O5 , K2 O on days 0, 3, 6 and 9. The results showed the optimum fermentation period was on the 6th day. The most optimum concentration of surimi liquid waste added was at a concentration of 90%, with characteristics of the products was C-organic 0.803 ± 0.0115 %, total N 740.063 ± 0.0862 ppm, C/N ratio 10.855 ± 0.1562, P2 O5 425.603 ± 0.2329 ppm, K2 O 2738.627 ± 0.2836 ppm.

  1. Cloud-point extraction is compatible with liquid chromatography coupled to electrospray ionization mass spectrometry for the determination of antazoline in human plasma.

    Science.gov (United States)

    Giebułtowicz, Joanna; Kojro, Grzegorz; Piotrowski, Roman; Kułakowski, Piotr; Wroczyński, Piotr

    2016-09-05

    Cloud-point extraction (CPE) is attracting increasing interest in a number of analytical fields, including bioanalysis, as it provides a simple, safe and environmentally-friendly sample preparation technique. However, there are only few reports on the application of this extraction technique in liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) analysis. In this study, CPE was used for the isolation of antazoline from human plasma. To date, only one method of antazoline isolation from plasma exists-liquid-liquid extraction (LLE). The aim of this study was to prove the compatibility of CPE and LC-ESI-MS/MS and the applicability of CPE to the determination of antazoline in spiked human plasma and clinical samples. Antazoline was isolated from human plasma using Triton X-114 as a surfactant. Xylometazoline was used as an internal standard. NaOH concentration, temperature and Triton X-114 concentration were optimized. The absolute matrix effect was carefully investigated. All validation experiments met international acceptance criteria and no significant relative matrix effect was observed. The compatibility of CPE and LC-ESI-MS/MS was confirmed using clinical plasma samples. The determination of antazoline concentration in human plasma in the range 10-2500ngmL(-1) by the CPE method led to results which are equivalent to those obtained by the widely used liquid-liquid extraction method. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Assessment of spanwise domain size effect on the transitional flow past an airfoil

    KAUST Repository

    Zhang, Wei

    2015-10-19

    In most large-eddy and direct numerical simulations of flow past an isolated airfoil, the flow is assumed periodic in the spanwise direction. The size of the spanwise domain is an important geometrical parameter determining whether the turbulent flow is fully developed, and whether the separation and transition patterns are accurately modeled. In the present study, we investigate the incompressible flow past an isolated NACA0012 airfoil at the angle of attack of 5 degrees and Reynolds number 5 × 104. The spanwise domain size Lz, represented by the aspect ratio AR=Lz/C where C is the airfoil chord length, is varied in the range 0.1−0.80.1−0.8. The effect of varying the normalized spanwise domain size AR is examined via direct numerical simulation (DNS) on several aspects of the turbulent flow quantities including the time-averaged and time-dependent behavior as well as the spanwise variation of the selected statistical quantities. DNS results reveal that different aspect ratios result in close predictions of the time-averaged aerodynamic quantities, and the velocity field except for a slight difference in the separation bubble. Smaller aspect ratios tend to underpredict the turbulent fluctuations near the separation point but overpredict them inside the separation bubble. Large differences are observed for multiple statistical quantities near the reattachment point, especially the turbulent kinetic energy budget terms. The leading edge separation is notably three-dimensional for simulation at AR=0.8, while remaining quasi-2D for smaller aspect ratios. The spanwise two-point correlation coefficient shows significant dependence on the position of the probe and the velocity component analyzed: small aspect ratios do not produce uncorrelated results for all the velocity components. The simulation results demonstrate that examining only a few statistical quantities may result in a misleading conclusion regarding the sufficiency of the spanwise domain size. Reliable

  3. Assessment of spanwise domain size effect on the transitional flow past an airfoil

    KAUST Repository

    Zhang, Wei; Samtaney, Ravi

    2015-01-01

    In most large-eddy and direct numerical simulations of flow past an isolated airfoil, the flow is assumed periodic in the spanwise direction. The size of the spanwise domain is an important geometrical parameter determining whether the turbulent flow is fully developed, and whether the separation and transition patterns are accurately modeled. In the present study, we investigate the incompressible flow past an isolated NACA0012 airfoil at the angle of attack of 5 degrees and Reynolds number 5 × 104. The spanwise domain size Lz, represented by the aspect ratio AR=Lz/C where C is the airfoil chord length, is varied in the range 0.1−0.80.1−0.8. The effect of varying the normalized spanwise domain size AR is examined via direct numerical simulation (DNS) on several aspects of the turbulent flow quantities including the time-averaged and time-dependent behavior as well as the spanwise variation of the selected statistical quantities. DNS results reveal that different aspect ratios result in close predictions of the time-averaged aerodynamic quantities, and the velocity field except for a slight difference in the separation bubble. Smaller aspect ratios tend to underpredict the turbulent fluctuations near the separation point but overpredict them inside the separation bubble. Large differences are observed for multiple statistical quantities near the reattachment point, especially the turbulent kinetic energy budget terms. The leading edge separation is notably three-dimensional for simulation at AR=0.8, while remaining quasi-2D for smaller aspect ratios. The spanwise two-point correlation coefficient shows significant dependence on the position of the probe and the velocity component analyzed: small aspect ratios do not produce uncorrelated results for all the velocity components. The simulation results demonstrate that examining only a few statistical quantities may result in a misleading conclusion regarding the sufficiency of the spanwise domain size. Reliable

  4. Preparation of Affinity Column Based on Zr{sup 4+} Ion for Phosphoproteins Isolation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seon Mi; Bae, In Ae; Park, Jung Hyen; Kim, Tae Dong; Choi, Seong Ho [Hannam University, Daejeon (Korea, Republic of)

    2009-06-15

    This paper has described about preparation of Zr{sup 4+} affinity column based on the poly(styreneco- glycidyl methacrylate) prepared by emulsion polymerization of styrene and glycidyl methacrylate in order to isolate phosphopeptide. The Zr{sup 4+} ions were introduced after the phophonation of an epoxy group on polymeric microspheres. The successful preparation of Zr{sup 4+}-immobilized polymeric microsphere stationary phase was confirmed through Fourier transform infrared spectra, optical microscopy, scanning electron microscopy, X-ray photoelectron spectra and inductively coupled plasma-atomic emission spectrometer. The separation efficiency for Zr{sup 4+} affinity column prepared by slurry packing was tested to phosphonated casein and dephosphonated casein. The resolution time (min) of the phosphonated casein was higher than that of dephosphated casein for Zr{sup 4+} affinity polymeric microsphere by liquid chromatography. This Zr{sup 4+} affinity column can be used for isolation of phosphonated casein from casein using liquid chromatography.

  5. The YARHG domain: an extracellular domain in search of a function.

    Directory of Open Access Journals (Sweden)

    Penny Coggill

    Full Text Available We have identified a new bacterial protein domain that we hypothesise binds to peptidoglycan. This domain is called the YARHG domain after the most highly conserved sequence-segment. The domain is found in the extracellular space and is likely to be composed of four alpha-helices. The domain is found associated with protein kinase domains, suggesting it is associated with signalling in some bacteria. The domain is also found associated with three different families of peptidases. The large number of different domains that are found associated with YARHG suggests that it is a useful functional module that nature has recombined multiple times.

  6. Enrichment, isolation and characterization of fungi tolerant to 1-ethyl-3-methylimidazolium acetate

    Energy Technology Data Exchange (ETDEWEB)

    Singer, S.W.; Reddy, A. P.; Gladden, J. M.; Guo, H.; Hazen, T.C.; Simmons, B. A.; VanderGheynst, J. S.

    2010-12-15

    This work aims to characterize microbial tolerance to 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]), ionic liquid that has emerged as a novel biomass pretreatment for lignocellulosic biomass. Enrichment experiments performed using inocula treated with [C2mim][OAc] under solid and liquid cultivation yielded fungal populationsdominated by Aspergilli. Ionic liquid-tolerant Aspergillus isolates from these enrichments were capable of growing in a radial plate growth assay in the presence of 10% [C2mim][OAc]. When a [C2mim][OAc]-tolerant Aspergillus fumigatus strain was grown in the presence of switchgrass, endoglucanases and xylanases were secreted that retained residual enzymatic activity in the presence of 20% [C2mim][OAc]. The results of the study suggest tolerance to ionic liquids is a general property of Aspergilli. Tolerance to an industrially important ionic liquid was discovered in a fungal genera that is widely used in biotechnology, including biomass deconstruction.

  7. Isolation of Cinnamic Acid Derivatives from the Bulbs of Allium tripedale

    Directory of Open Access Journals (Sweden)

    Zahra Chehri

    2018-01-01

    Full Text Available Background: Allium genus with 750 species is the most diverse genus in the Amaryllidaceae family. Historically, Allium species have been used as medicinal plants, especially for prevention and treatment of cardiovascular diseases and considered as valuable sources of phytonutrients. Phytochemical investigation of Allium tripedale, locally called “Anashq,” which is an edible plant of the “Zagros” region (west of Iran was conducted in the present study. Materials and Methods: Air-dried bulbs of the plant were extracted in a four-step extraction method with increasing polarity using hexane, chloroform, chloroform–methanol (9:1, and methanol. Chloroform-methanol (9:1 extract was fractionated by medium-pressure liquid chromatography on a RP-18 column using a linear gradient solvent system of H2O to MeOH. Phenolic-rich fractions were subjected to the final isolation and purification of the constituents by reversed-phase high-performance liquid chromatography method. Structure elucidation of the compounds was performed through comprehensive methods including 1D-and 2D-NMR and mass spectroscopy. Results: Two cinnamic acid derivatives were isolated from the bulbs of A. tripedale; using spectroscopic methods, their chemical structures were determined as 6,7-dimethoxy N-trans-caffeoyltyramine (1 and N-trans-feruloyltyramine (2. Conclusion: Cinnamic acid derivatives are pharmacologically active phenolic compounds, which have been isolated from different Allium species. Isolation of these compounds from A. tripedale is reported for the first time in this study and could be used as a chemical basis for explanation of the plant biological and pharmacological activities.

  8. Low-cost viscometer based on energy dissipation in viscous liquids

    Science.gov (United States)

    Hashimoto, C.; Cristobal, G.; Nicolas, A.; Panizza, P.; Rouch, J.; Ushiki, H.

    2001-04-01

    We describe a new type of low-cost easy-to-use viscometer based on the temperature elevation in a liquid under shear flow. After calibration, this instrument can be used to measure the apparent steady state viscosity for both Newtonian and non-Newtonian liquids with no yield stress. We compute the rise in temperature due to viscous dissipation in a Couette cell and compare it to experimental results for different fluids. We show that the variation of the temperature with shear rate can be used to characterize the rheological behaviour of viscous fluids and to evaluate their viscosity in a large domain, from typically a few cP up to more than 10 P, with an accuracy of about ±5%. In contrast to simple viscometers, non-Newtonian fluids can be studied with this apparatus. We give experimental results for Newtonian and non-Newtonian liquids and show that they are very similar to those given in the literature by using much more sophisticated instruments.

  9. Dynamic trafficking of wheat γ-gliadin and of its structural domains in tobacco cells, studied with fluorescent protein fusions

    Science.gov (United States)

    Francin-Allami, Mathilde; Saumonneau, Amélie; Lavenant, Laurence; Bouder, Axelle; Sparkes, Imogen; Hawes, Chris; Popineau, Yves

    2011-01-01

    Prolamins, the main storage proteins of wheat seeds, are synthesized and retained in the endoplasmic reticulum (ER) of the endosperm cells, where they accumulate in protein bodies (PBs) and are then exported to the storage vacuole. The mechanisms leading to these events are unresolved. To investigate this unconventional trafficking pathway, wheat γ-gliadin and its isolated repeated N-terminal and cysteine-rich C-terminal domains were fused to fluorescent proteins and expressed in tobacco leaf epidermal cells. The results indicated that γ-gliadin and both isolated domains were able to be retained and accumulated as protein body-like structures (PBLS) in the ER, suggesting that tandem repeats are not the only sequence involved in γ-gliadin ER retention and PBLS formation. The high actin-dependent mobility of γ-gliadin PBLS is also reported, and it is demonstrated that most of them do not co-localize with Golgi body or pre-vacuolar compartment markers. Both γ-gliadin domains are found in the same PBLS when co-expressed, which is most probably due to their ability to interact with each other, as indicated by the yeast two-hybrid and FRET-FLIM experiments. Moreover, when stably expressed in BY-2 cells, green fluorescent protein (GFP) fusions to γ-gliadin and its isolated domains were retained in the ER for several days before being exported to the vacuole in a Golgi-dependent manner, and degraded, leading to the release of the GFP ‘core’. Taken together, the results show that tobacco cells are a convenient model to study the atypical wheat prolamin trafficking with fluorescent protein fusions. PMID:21617248

  10. Saturnispora bothae sp. nov., isolated from rotting wood.

    Science.gov (United States)

    Morais, Camila G; Lara, Carla A; Borelli, Beatriz M; Cadete, Raquel M; Moreira, Juliana D; Lachance, Marc-André; Rosa, Carlos A

    2016-10-01

    Two strains representing a novel species of the genus Saturnispora were isolated from rotting wood samples collected in an Atlantic Rainforest site in Brazil. Analyses of the sequences of the D1/D2 domains of the rRNA gene showed that this novel species belongs to a subclade in the Saturnispora clade formed by Saturnispora sanitii, Saturnispora sekii, Saturnispora silvae and Saturnisporasuwanaritii. The novel species differed in D1/D2 sequences by 60 or more nucleotide substitutions from these species. The strains produced asci with one to four hemispherical ascospores. A novel species named Saturnispora bothae sp. nov. is proposed to accommodate these isolates. The type strain is UFMG-CM-Y292T (=CBS 13484T). The MycoBank number is MB 817127.

  11. Bismuth-ceramic nanocomposites through ball milling and liquid crystal synthetic methods

    Science.gov (United States)

    Dellinger, Timothy Michael

    Three methods were developed for the synthesis of bismuth-ceramic nanocomposites, which are of interest due to possible use as thermoelectric materials. In the first synthetic method, high energy ball milling of bismuth metal with either MgO or SiO2 was found to produce nanostructured bismuth dispersed on a ceramic material. The morphology of the resulting bismuth depended on its wetting behavior with respect to the ceramic: the metal wet the MgO, but did not wet on the SiO2. Differential Scanning Calorimetry measurements on these composites revealed unusual thermal stability, with nanostructure retained after multiple cycles of heating and cooling through the metal's melting point. The second synthesis methodology was based on the use of lyotropic liquid crystals. These mixtures of water and amphiphilic molecules self-assemble to form periodic structures with nanometer-scale hydrophilic and hydrophobic domains. A novel shear mixing methodology was developed for bringing together reactants which were added to the liquid crystals as dissolved salts. The liquid crystals served to mediate synthesis by acting as nanoreactors to confine chemical reactions within the nanoscale domains of the mesophase, and resulted in the production of nanoparticles. By synthesizing lead sulfide (PbS) and bismuth (Bi) particles as proof-of-concept, it was shown that nanoparticle size could be controlled by controlling the dimensionality of the nanoreactors through control of the liquid crystalline phase. Particle size was shown to decrease upon going from three-dimensionally percolating nanoreactors, to two dimensional sheet-like nanoreactors, to one dimensional rod-like nanoreactors. Additionally, particle size could be controlled by varying the precursor salt concentration. Since the nanoparticles did not agglomerate in the liquid crystal immediately after synthesis, bismuth-ceramic nanocomposites could be prepared by synthesizing Bi nanoparticles and mixing in SiO2 particles which

  12. PREFACE: Functionalized Liquid Liquid Interfaces

    Science.gov (United States)

    Girault, Hubert; Kornyshev, Alexei A.; Monroe, Charles W.; Urbakh, Michael

    2007-09-01

    Most natural processes take place at interfaces. For this reason, surface science has been a focal point of modern research. At solid-liquid interfaces one can induce various species to adsorb or react, and thus may study interactions between the substrate and adsorbates, kinetic processes, optical properties, etc. Liquid-liquid interfaces, formed by immiscible liquids such as water and oil, have a number of distinctive features. Both sides of the interface are amenable to detailed physical and chemical analysis. By chemical or electrochemical means, metal or semiconductor nanoparticles can be formed or localised at the interface. Surfactants can be used to tailor surface properties, and also to place organic molecular or supermolecular constructions at the boundary between the liquids. Electric fields can be used to drive ions from one fluid to another, or even change the shape of the interface itself. In many cases, both liquids are optically transparent, making functionalized liquid-liquid interfaces promising for various optical applications based on the transmission or reflection of light. An advantage common to most of these systems is self-assembly; because a liquid-liquid interface is not mechanically constrained like a solid-liquid interface, it can easily access its most stable state, even after it has been driven far from equilibrium. This special issue focuses on four modes of liquid-liquid interfacial functionalization: the controlled adsorption of molecules or nanoparticles, the formation of adlayers or films, electrowetting, and ion transfer or interface-localized reactions. Interfacial adsorption can be driven electrically, chemically, or mechanically. The liquid-liquid interface can be used to study how anisotropic particles orient at a surface under the influence of a field, how surfactants interact with other adsorbates, and how nanoparticles aggregate; the transparency of the interface also makes the chirality of organic adsorbates amenable to

  13. Directed evolution of the TALE N-terminal domain for recognition of all 5' bases.

    Science.gov (United States)

    Lamb, Brian M; Mercer, Andrew C; Barbas, Carlos F

    2013-11-01

    Transcription activator-like effector (TALE) proteins can be designed to bind virtually any DNA sequence. General guidelines for design of TALE DNA-binding domains suggest that the 5'-most base of the DNA sequence bound by the TALE (the N0 base) should be a thymine. We quantified the N0 requirement by analysis of the activities of TALE transcription factors (TALE-TF), TALE recombinases (TALE-R) and TALE nucleases (TALENs) with each DNA base at this position. In the absence of a 5' T, we observed decreases in TALE activity up to >1000-fold in TALE-TF activity, up to 100-fold in TALE-R activity and up to 10-fold reduction in TALEN activity compared with target sequences containing a 5' T. To develop TALE architectures that recognize all possible N0 bases, we used structure-guided library design coupled with TALE-R activity selections to evolve novel TALE N-terminal domains to accommodate any N0 base. A G-selective domain and broadly reactive domains were isolated and characterized. The engineered TALE domains selected in the TALE-R format demonstrated modularity and were active in TALE-TF and TALEN architectures. Evolved N-terminal domains provide effective and unconstrained TALE-based targeting of any DNA sequence as TALE binding proteins and designer enzymes.

  14. .Gov Domains API

    Data.gov (United States)

    General Services Administration — This dataset offers the list of all .gov domains, including state, local, and tribal .gov domains. It does not include .mil domains, or other federal domains outside...

  15. Ultrabroadband THz Time-Domain Spectroscopy of a Free-Flowing Water Film

    DEFF Research Database (Denmark)

    Wang, Tianwu; Pedersen, Pernille Klarskov; Jepsen, Peter Uhd

    2014-01-01

    of liquid water using two different THz-TDS setups. The extracted absorption coefficient and refractive index of water are in agreement with previous results reported in the literature. With this we show that the thin free-flowing liquid film is a versatile tool for windowless, ultrabroadband THz......We demonstrate quantitative ultrabroadband THz time-domain spectroscopy (THz-TDS) of water by application of a 17-$\\mu$m thick gravity-driven wire-guided flow jet of water. The thickness and stability of the water film is accurately measured by an optical intensity crosscorrelator, and the standard...... deviation of the film thickness is less than 500 nm. The cross section of the water film is found to have a biconcave cylindrical lens shape. By transmitting through such a thin film, we perform the first ultrabroadband (0.2–30 THz) THz-TDS across the strongest absorbing part of the infrared spectrum...

  16. Attosecond electron dynamics in molecules and liquids

    Science.gov (United States)

    WöRner, Hans Jakob

    The ultrafast motion of electrons and holes following light-matter interaction is fundamental to a broad range of chemical and biophysical processes. In this lecture, I will discuss some of our recent experiments that measure the atomic-scale motion of charge with attosecond temporal resolution (1 as = 10-18s). The first experiment is carried out on isolated, spatially oriented molecules in the gas phase. Using high-harmonic spectroscopy, we resolve the migration of an electron hole across the molecule with a resolution of 100 as and simultaneously demonstrate extensive control over charge migration. In the second class of experiments, we use an attosecond pulse train synchronized with a near-infrared laser pulse to temporally resolve the process of photoemission from molecules in the gas phase and from a liquid-water microjet, resolving electron transport through liquid water on the attosecond time scale.

  17. Functions and requirements document, WESF decoupling project, low-level liquid waste system

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, J.H., Fluor Daniel Hanford

    1997-02-27

    The Waste Encapsulation and Storage Facility (WESF) was constructed in 1974 to encapsulate and store cesium and strontium which were isolated at B Plant from underground storage tank waste. The WESF, Building 225-B, is attached physically to the west end of B Plant, Building 221-B, 200 East area. The WESF currently utilizes B Plant facilities for disposing liquid and solid waste streams. With the deactivation of B Plant, the WESF Decoupling Project will provide replacement systems allowing WESF to continue operations independently from B Plant. Four major systems have been identified to be replaced by the WESF Decoupling Project, including the following: Low Level Liquid Waste System, Solid Waste Handling System, Liquid Effluent Control System, and Deionized Water System.

  18. Definition and means of maintaining the process vacuum liquid detection interlock systems portion of the PFP safety envelope

    International Nuclear Information System (INIS)

    THOMAS, R.J.

    1999-01-01

    The Process Vacuum Liquid Detection interlock systems prevent intrusion of process liquids into the HEPA filters downstream of demisters No.6 and No.7 during Process Vacuum System operation. This prevents liquid intrusion into the filters, which could cause a criticality. The Safety Envelope (SE) includes the equipment, which detects the presence of liquids in the vacuum headers; isolates the filters; shuts down the vacuum pumps; and alarms the condition. This report identifies the equipment in the SE operating, maintenance, and surveillance procedures needed to maintain the SE equipment; and rationale for exclusion of some equipment and testing from the SE

  19. Analytical Stationary Acoustic Wave in a Liquid over Which a Moving Pressure Runs

    Directory of Open Access Journals (Sweden)

    André Langlet

    2010-01-01

    Full Text Available This paper presents an analytical study of the stationary response of a liquid loaded on its free surface by an ideal pressure step moving in a constant direction at a constant velocity. The acoustic pressure in the liquid is found, in four different examples, by means of the Fourier Transform. Two loading regimes are considered; subsonic and supersonic. Two configurations of liquid domains are also studied, the first one is a half infinite space while the second one is bounded by a rigid bottom at a finite depth. For the two supersonic cases, a simple reasoning based on the existence of a front of discontinuity in the liquid and on the property of reflection of waves confirms the result of the mathematical investigations. The results obtained for the steady state case are of intererest, even when the loading is not exactly stationary, such as the presure produced by an explosion occurring in the vicinity of the surface of a liquid. Two numerically resolved examples are presented, which confirm this assumption.

  20. Fiber optic liquid-level sensor using a long fiber Bragg grating

    Science.gov (United States)

    Ricchiuti, Amelia L.; Barrera, David; Nonaka, Koji; Sales, Salvador

    2013-05-01

    A technique for liquid-level sensors based on a long fiber Bragg grating (FBG) is presented and experimentally demonstrated. The measurement system is based on the measurement of the central frequency distribution of the FBG based on time-frequency domain analysis. A short optical pulse is injected into a 10-cm long FBG mounted in a container. The back-reflected pulse is scanned by means of an oscilloscope. When part of the grating is immersed in a liquid having temperature higher than the surrounding ambient, the structure of the uniform grating is distorted and its time-frequency response changes. A spatial resolution of 2 mm, given by the input pulse duration, and a 10-cm long measurement range are achieved. Liquid-temperature sensing has also been implemented by scanning the spectral response of the FBG by means of a CW laser and an OSA.

  1. Crystal Structure of Glucagon-like Peptide-1 in Complex with the Extracellular Domain of the Glucagon-like Peptide-1 Receptor*

    Science.gov (United States)

    Underwood, Christina Rye; Garibay, Patrick; Knudsen, Lotte Bjerre; Hastrup, Sven; Peters, Günther H.; Rudolph, Rainer; Reedtz-Runge, Steffen

    2010-01-01

    GLP-1 (glucagon-like peptide-1) is an incretin released from intestinal L-cells in response to food intake. Activation of the GLP-1 receptor potentiates the synthesis and release of insulin from pancreatic β-cells in a glucose-dependent manner. The GLP-1 receptor belongs to class B of the G-protein-coupled receptors, a subfamily characterized by a large N-terminal extracellular ligand binding domain. Exendin-4 and GLP-1 are 50% identical, and exendin-4 is a full agonist with similar affinity and potency for the GLP-1 receptor. We recently solved the crystal structure of the GLP-1 receptor extracellular domain in complex with the competitive antagonist exendin-4(9–39). Interestingly, the isolated extracellular domain binds exendin-4 with much higher affinity than the endogenous agonist GLP-1. Here, we have solved the crystal structure of the extracellular domain in complex with GLP-1 to 2.1 Åresolution. The structure shows that important hydrophobic ligand-receptor interactions are conserved in agonist- and antagonist-bound forms of the extracellular domain, but certain residues in the ligand-binding site adopt a GLP-1-specific conformation. GLP-1 is a kinked but continuous α-helix from Thr13 to Val33 when bound to the extracellular domain. We supplemented the crystal structure with site-directed mutagenesis to link the structural information of the isolated extracellular domain with the binding properties of the full-length receptor. The data support the existence of differences in the binding modes of GLP-1 and exendin-4 on the full-length GLP-1 receptor. PMID:19861722

  2. The effects of glutamine/asparagine content on aggregation and heterologous prion induction by yeast prion-like domains.

    Science.gov (United States)

    Shattuck, Jenifer E; Waechter, Aubrey C; Ross, Eric D

    2017-07-04

    Prion-like domains are low complexity, intrinsically disordered domains that compositionally resemble yeast prion domains. Many prion-like domains are involved in the formation of either functional or pathogenic protein aggregates. These aggregates range from highly dynamic liquid droplets to highly ordered detergent-insoluble amyloid-like aggregates. To better understand the amino acid sequence features that promote conversion to stable, detergent-insoluble aggregates, we used the prediction algorithm PAPA to identify predicted aggregation-prone prion-like domains with a range of compositions. While almost all of the predicted aggregation-prone domains formed foci when expressed in cells, the ability to form the detergent-insoluble aggregates was highly correlated with glutamine/asparagine (Q/N) content, suggesting that high Q/N content may specifically promote conversion to the amyloid state in vivo. We then used this data set to examine cross-seeding between prion-like proteins. The prion protein Sup35 requires the presence of a second prion, [PIN + ], to efficiently form prions, but this requirement can be circumvented by the expression of various Q/N-rich protein fragments. Interestingly, almost all of the Q/N-rich domains that formed SDS-insoluble aggregates were able to promote prion formation by Sup35, highlighting the highly promiscuous nature of these interactions.

  3. Comparison of seismic response of ordinary and base-isolated structures

    International Nuclear Information System (INIS)

    Kuroda, T.; Kobatake, M.; Seidensticker, R.W.; Chang, Y.W.

    1992-01-01

    Seismic isolation is growing rapidly worldwide as a cost-effective and reliable design strategy for a wide range of critical and important facilities (e.g., hospitals, computer centers, etc.) Shimizu Corporation of Japan has a test facility at Tohoku University in Sendai, Japan. The test facility was constructed in 1986 and has two buildings: one is base isolated and the other is conventionally founded. The buildings are full-size, three-story reinforced concrete structures. The dimensions and construction of the superstructures are identical. For the past several years, Shimizu Corporation has installed a number of different isolation systems in the isolated building at the test facility to study the response of base isolation systems to actual earthquake motions. Argonne National Laboratory (ANL) has been deeply involved in the development of seismic isolation for use in nuclear facilities for the past decade. Using the funding and direction of the US Department of Energy (USDOE), ANL has been developing methodology needed to evaluate the usefulness and effectiveness of seismic isolation for advanced liquid metal-cooled reactors (LMRs). This paper compares the seismic responses of ordinary and base-isolated buildings. Earthquake records of significant importance from April 1989 to September 1991, after the installation of bearings have been analyzed. Numerical simulations of the building responses have been performed and correlated with earthquake observation data. It is hoped that the results of this study will provide guidelines for the future use of isolator bearings for mitigation of earthquake damages

  4. Same but not alike: Structure, flexibility and energetics of domains in multi-domain proteins are influenced by the presence of other domains.

    Science.gov (United States)

    Vishwanath, Sneha; de Brevern, Alexandre G; Srinivasan, Narayanaswamy

    2018-02-01

    The majority of the proteins encoded in the genomes of eukaryotes contain more than one domain. Reasons for high prevalence of multi-domain proteins in various organisms have been attributed to higher stability and functional and folding advantages over single-domain proteins. Despite these advantages, many proteins are composed of only one domain while their homologous domains are part of multi-domain proteins. In the study presented here, differences in the properties of protein domains in single-domain and multi-domain systems and their influence on functions are discussed. We studied 20 pairs of identical protein domains, which were crystallized in two forms (a) tethered to other proteins domains and (b) tethered to fewer protein domains than (a) or not tethered to any protein domain. Results suggest that tethering of domains in multi-domain proteins influences the structural, dynamic and energetic properties of the constituent protein domains. 50% of the protein domain pairs show significant structural deviations while 90% of the protein domain pairs show differences in dynamics and 12% of the residues show differences in the energetics. To gain further insights on the influence of tethering on the function of the domains, 4 pairs of homologous protein domains, where one of them is a full-length single-domain protein and the other protein domain is a part of a multi-domain protein, were studied. Analyses showed that identical and structurally equivalent functional residues show differential dynamics in homologous protein domains; though comparable dynamics between in-silico generated chimera protein and multi-domain proteins were observed. From these observations, the differences observed in the functions of homologous proteins could be attributed to the presence of tethered domain. Overall, we conclude that tethered domains in multi-domain proteins not only provide stability or folding advantages but also influence pathways resulting in differences in

  5. Indentification of huperzine A-producing endophytic fungi isolated from Huperzia serrata.

    Science.gov (United States)

    Dong, Li-Hui; Fan, San-Wei; Ling, Qing-Zhi; Huang, Bei-Bei; Wei, Zhao-Jun

    2014-03-01

    This present study was designed to investigate the production of huperzine A (HupA), an acetylcholine inhibitor, which was produced by an endophytic fungi isolated from Huperzia serrata. Screening of 94 endophytic fungal isolates obtained from plant H. serrata was carried out for the production of HupA. Their morphological characteristics were studied and rDNA sequence analysis was carried out. The cultures were grown in liquid culture medium and the extracted metabolites were analyzed by thin layer chromatography and high performance liquid chromatograph for the presence of HupA. The DPPH scavenging ratio and inhibition ratio of acetylcholinesterase (AchE) of the same were determined. 3 out of 94 strains i.e. S29, L44 and S94 showed significant AchE-inhibitory activity and antioxidant activity. Strain L44 which exhibited maximum yield of HupA (37.63 μg/g on dry weight basis) was identified as Trichoderma species by ITS sequence analysis. In conclusion, endophytic fungi from H. serrata can be used as a new resource of HupA.

  6. Assembly of Oligomeric Death Domain Complexes during Toll Receptor Signaling*

    Science.gov (United States)

    Moncrieffe, Martin C.; Grossmann, J. Günter; Gay, Nicholas J.

    2008-01-01

    The Drosophila Toll receptor is activated by the endogenous protein ligand Spätzle in response to microbial stimuli in immunity and spatial cues during embryonic development. Downstream signaling is mediated by the adaptor proteins Tube, the kinase Pelle, and the Drosophila homologue of myeloid differentiation primary response protein (dMyD88). Here we have characterized heterodimeric (dMyD88-Tube) and heterotrimeric (dMyD88-Tube-Pelle) death domain complexes. We show that both the heterodimeric and heterotrimeric complexes form kidney-shaped structures and that Tube is bivalent and has separate high affinity binding sites for dMyD88 and Pelle. Additionally we found no interaction between the isolated death domains of Pelle and dMyD88. These results indicate that the mode of assembly of the heterotrimeric dMyD88-Tube-Pelle complex downstream of the activated Toll receptor is unique. The measured dissociation constants for the interaction between the death domains of dMyD88 and Tube and of Pelle and a preformed dMyD88-Tube complex are used to propose a model of the early postreceptor events in Drosophila Toll receptor signaling. PMID:18829464

  7. Assembly of oligomeric death domain complexes during Toll receptor signaling.

    Science.gov (United States)

    Moncrieffe, Martin C; Grossmann, J Günter; Gay, Nicholas J

    2008-11-28

    The Drosophila Toll receptor is activated by the endogenous protein ligand Spätzle in response to microbial stimuli in immunity and spatial cues during embryonic development. Downstream signaling is mediated by the adaptor proteins Tube, the kinase Pelle, and the Drosophila homologue of myeloid differentiation primary response protein (dMyD88). Here we have characterized heterodimeric (dMyD88-Tube) and heterotrimeric (dMyD88-Tube-Pelle) death domain complexes. We show that both the heterodimeric and heterotrimeric complexes form kidney-shaped structures and that Tube is bivalent and has separate high affinity binding sites for dMyD88 and Pelle. Additionally we found no interaction between the isolated death domains of Pelle and dMyD88. These results indicate that the mode of assembly of the heterotrimeric dMyD88-Tube-Pelle complex downstream of the activated Toll receptor is unique. The measured dissociation constants for the interaction between the death domains of dMyD88 and Tube and of Pelle and a preformed dMyD88-Tube complex are used to propose a model of the early postreceptor events in Drosophila Toll receptor signaling.

  8. Attosecond dynamics of electrons in molecules and liquids

    Science.gov (United States)

    Woerner, Hans Jakob

    2016-05-01

    The ultrafast motion of electrons and holes following light-matter interaction is fundamental to a broad range of chemical and biophysical processes. In this lecture, I will discuss two recent experiments carried out in our group that measure the atomic-scale motion of charge with attosecond temporal resolution (1 as = 10-18 s). The first experiment is carried out on isolated, spatially oriented molecules in the gas phase. We advance high-harmonic spectroscopy to resolve spatially and temporally the migration of an electron hole immediately following ionization of iodoacetylene, while simultaneously demonstrating extensive control over the process. A multidimensional approach, based on the measurement of both even and odd harmonic orders, enables us to reconstruct both quantum amplitudes and phases of the electronic states with a resolution of ~ 100 as. We separately reconstruct quasi-field-free and laser-controlled charge migration as a function of the spatial orientation of the molecule and determine the shape of the hole created by ionization. The second experiment is carried out on a free-flowing microjet of liquid water. We use an attosecond pulse train synchronized with a near-infrared laser pulse to temporally resolve the process of photoemission from liquid water using the RABBIT technique. We measure a delay on the order of 50 as between electrons emitted from the HOMO of liquid water compared to that of gas-phase water and a substantially reduced modulation contrast of the corresponding sidebands. Since our measurements on solvated water molecules are referenced to isolated ones, the measured delays reflect (i) the photoionization delays caused by electron transport through the aqueous environment and (ii) the effect of solvation on the parent molecule. The relative modulation contrast, in turn, contains information on (iii) the modification of transition amplitudes and (iv) dephasing processes. These experiments make the liquid phase and its fascinating

  9. The sedimentation of fine particles in liquid foams

    OpenAIRE

    Rouyer , Florence; Fritz , Christelle; Pitois , Olivier

    2010-01-01

    International audience; We investigate the sedimentation of fine particles in liquid channels of foams. The study combines numerical simulations with experiments performed in foams and in isolated vertical foam channels. Results show that particulate motion is controlled by the confinement parameter (l) and the mobility of the channel surfaces modelled by interfacial shear viscosity. Interestingly, whereas the position of the particle within the channel cross-section is expected to be a relev...

  10. Novel 2-Alkyl-1-Ethylpyridinium ionic liquids : synthesis, dissociation energies and volatility

    NARCIS (Netherlands)

    Vilas, M.; Alves da Rocha, M.A.; Fernandes, A.M.; Tojo, E.; Santos, L.M.N.B.F.

    2015-01-01

    This work presents the synthesis, volatility study and electrospray ionization mass spectrometry with energy-variable collision induced dissociation of the isolated [(cation)2(anion)]+ of a novel series of 2-alkyl-1-ethyl pyridinium based ionic liquids, [2CN-21C2Py][NTf2]. Compared to the

  11. Extraction and Purification of Glucoraphanin by Preparative High-Performance Liquid Chromatography (HPLC)

    Science.gov (United States)

    Lee, Iris; Boyce, Mary C.

    2011-01-01

    A student activity that focuses on the isolation of glucoraphanin from broccoli using preparative high-performance liquid chromatography (HPLC) is presented here. Glucoraphanin is a glucosinolate, whose byproducts are known to possess anticancer properties. It is present naturally at high levels in broccoli and other "Brassica" vegetables. This…

  12. Isolation and identification of acetogenic bacteria obtained from deer rumen and their potential for methanogenesis inhibitor

    Directory of Open Access Journals (Sweden)

    Amlius Thalib

    2008-10-01

    Full Text Available Methanogenesis can be inhibited by various chemicals through different mechanism reaktion. The use of acetogenic bacteria as H2 sink is assumed to be a promising approach. Isolation and identification of acetogenic bacteria obtained from deer rumen had been conducted. Two types of media used for isolation were hydrogen-carbondioxide utilizing acetogens and carbonmonoxide utilizing acetogens. Identification of species of acetogens isolates was based on descriptions of morphology, Gram type, motility, bioreaction results, and oksygen requirement. The compositions of methane and volatile fatty acids (VFA were determined on minimal media or added with sheep rumen liquid innoculated with pure isolates. The identification results showed that the isolate cultured on media of hydrogen-carbondioxide utilizing acetogens was Acetoanaerobium noterae and the ones cultured on media of carbonmonoxide utilizing acetogens was Acetobacterium woodii. Inoculumn of A. noterae and A. woodii could decreased the composition of methane resulted from substrate fermented by fresh rumen liquid of sheep (CRDF, that is culture of A. noterae added FPM and defaunator decreased methane production by 28.8% (P CH3COOH + 2H2O by which reduction of CO2 with H2 producing CH4 can be inhibited or decreased. Their function as methanogenesis inhibitor would be more significant when they are combined with microbial growth factors and defaunator.

  13. High-resolution bistable nematic liquid crystal device realized on orientational surface patterns

    International Nuclear Information System (INIS)

    Kim, Jong-Hyun; Yoneya, Makoto; Yokoyama, Hiroshi

    2003-01-01

    The four-fold symmetry of a checkerboard-like surface alignment consisted of square domains arrived at the macroscopic orientational bistability of nematic liquid crystals. Switching between the two orientations took place with an appropriate electric field. Here the threshold field of bistable switching decreased as temperature increased, and the light could heat only the selected region in the cell including a light-absorbing medium. Irradiating the laser concurrently with an electric field, we addressed a selected region in the alignment pattern without the disturbance of neighboring regions. Extending this process, we realized an extremely fine bistable device of nematic liquid crystal with a pixel size down to about 2 μm

  14. Different Binding Properties and Function of CXXC Zinc Finger Domains in Dnmt1 and Tet1

    Science.gov (United States)

    Meilinger, Daniela; Bultmann, Sebastian; Fellinger, Karin; Hasenöder, Stefan; Wang, Mengxi; Qin, Weihua; Söding, Johannes; Spada, Fabio; Leonhardt, Heinrich

    2011-01-01

    Several mammalian proteins involved in chromatin and DNA modification contain CXXC zinc finger domains. We compared the structure and function of the CXXC domains in the DNA methyltransferase Dnmt1 and the methylcytosine dioxygenase Tet1. Sequence alignment showed that both CXXC domains have a very similar framework but differ in the central tip region. Based on the known structure of a similar MLL1 domain we developed homology models and designed expression constructs for the isolated CXXC domains of Dnmt1 and Tet1 accordingly. We show that the CXXC domain of Tet1 has no DNA binding activity and is dispensable for catalytic activity in vivo. In contrast, the CXXC domain of Dnmt1 selectively binds DNA substrates containing unmethylated CpG sites. Surprisingly, a Dnmt1 mutant construct lacking the CXXC domain formed covalent complexes with cytosine bases both in vitro and in vivo and rescued DNA methylation patterns in dnmt1−/− embryonic stem cells (ESCs) just as efficiently as wild type Dnmt1. Interestingly, neither wild type nor ΔCXXC Dnmt1 re-methylated imprinted CpG sites of the H19a promoter in dnmt1−/− ESCs, arguing against a role of the CXXC domain in restraining Dnmt1 methyltransferase activity on unmethylated CpG sites. PMID:21311766

  15. Different binding properties and function of CXXC zinc finger domains in Dnmt1 and Tet1.

    Directory of Open Access Journals (Sweden)

    Carina Frauer

    2011-02-01

    Full Text Available Several mammalian proteins involved in chromatin and DNA modification contain CXXC zinc finger domains. We compared the structure and function of the CXXC domains in the DNA methyltransferase Dnmt1 and the methylcytosine dioxygenase Tet1. Sequence alignment showed that both CXXC domains have a very similar framework but differ in the central tip region. Based on the known structure of a similar MLL1 domain we developed homology models and designed expression constructs for the isolated CXXC domains of Dnmt1 and Tet1 accordingly. We show that the CXXC domain of Tet1 has no DNA binding activity and is dispensable for catalytic activity in vivo. In contrast, the CXXC domain of Dnmt1 selectively binds DNA substrates containing unmethylated CpG sites. Surprisingly, a Dnmt1 mutant construct lacking the CXXC domain formed covalent complexes with cytosine bases both in vitro and in vivo and rescued DNA methylation patterns in dnmt1⁻/⁻ embryonic stem cells (ESCs just as efficiently as wild type Dnmt1. Interestingly, neither wild type nor ΔCXXC Dnmt1 re-methylated imprinted CpG sites of the H19a promoter in dnmt1⁻/⁻ ESCs, arguing against a role of the CXXC domain in restraining Dnmt1 methyltransferase activity on unmethylated CpG sites.

  16. Molecular basis of the specific subcellular localization of the C2-like domain of 5-lipoxygenase.

    Science.gov (United States)

    Kulkarni, Shilpa; Das, Sudipto; Funk, Colin D; Murray, Diana; Cho, Wonhwa

    2002-04-12

    The activation of 5-lipoxygenase (5-LO) involves its calcium-dependent translocation to the nuclear envelope, where it catalyzes the two-step transformation of arachidonic acid into leukotriene A(4), leading to the synthesis of various leukotrienes. To understand the mechanism by which 5-LO is specifically targeted to the nuclear envelope, we studied the membrane binding properties of the amino-terminal domain of 5-LO, which has been proposed to have a C2 domain-like structure. The model building, electrostatic potential calculation, and in vitro membrane binding studies of the isolated C2-like domain of 5-LO and selected mutants show that this Ca(2+)-dependent domain selectively binds zwitterionic phosphatidylcholine, which is conferred by tryptophan residues (Trp(13), Trp(75), and Trp(102)) located in the putative Ca(2+)-binding loops. The spatiotemporal dynamics of the enhanced green fluorescence protein-tagged C2-like domain of 5-LO and mutants in living cells also show that the phosphatidylcholine selectivity of the C2-like domain accounts for the specific targeting of 5-LO to the nuclear envelope. Together, these results show that the C2-like domain of 5-LO is a genuine Ca(2+)-dependent membrane-targeting domain and that the subcellular localization of the domain is governed in large part by its membrane binding properties.

  17. Algorithm design of liquid lens inspection system

    Science.gov (United States)

    Hsieh, Lu-Lin; Wang, Chun-Chieh

    2008-08-01

    In mobile lens domain, the glass lens is often to be applied in high-resolution requirement situation; but the glass zoom lens needs to be collocated with movable machinery and voice-coil motor, which usually arises some space limits in minimum design. In high level molding component technology development, the appearance of liquid lens has become the focus of mobile phone and digital camera companies. The liquid lens sets with solid optical lens and driving circuit has replaced the original components. As a result, the volume requirement is decreased to merely 50% of the original design. Besides, with the high focus adjusting speed, low energy requirement, high durability, and low-cost manufacturing process, the liquid lens shows advantages in the competitive market. In the past, authors only need to inspect the scrape defect made by external force for the glass lens. As to the liquid lens, authors need to inspect the state of four different structural layers due to the different design and structure. In this paper, authors apply machine vision and digital image processing technology to administer inspections in the particular layer according to the needs of users. According to our experiment results, the algorithm proposed can automatically delete non-focus background, extract the region of interest, find out and analyze the defects efficiently in the particular layer. In the future, authors will combine the algorithm of the system with automatic-focus technology to implement the inside inspection based on the product inspective demands.

  18. Electrically tunable terahertz polarization converter based on overcoupled metal-isolator-metal metamaterials infiltrated with liquid crystals

    Science.gov (United States)

    Vasić, Borislav; Zografopoulos, Dimitrios C.; Isić, Goran; Beccherelli, Romeo; Gajić, Radoš

    2017-03-01

    Large birefringence and its electrical modulation by means of Fréedericksz transition makes nematic liquid crystals (LCs) a promising platform for tunable terahertz (THz) devices. The thickness of standard LC cells is in the order of the wavelength, requiring high driving voltages and allowing only a very slow modulation at THz frequencies. Here, we first present the concept of overcoupled metal-isolator-metal (MIM) cavities that allow for achieving simultaneously both very high phase difference between orthogonal electric field components and large reflectance. We then apply this concept to LC-infiltrated MIM-based metamaterials aiming at the design of electrically tunable THz polarization converters. The optimal operation in the overcoupled regime is provided by properly selecting the thickness of the LC cell. Instead of the LC natural birefringence, the polarization-dependent functionality stems from the optical anisotropy of ultrathin and deeply subwavelength MIM structures. The dynamic electro-optic control of the LC refractive index enables the spectral shift of the resonant mode and, consequently, the tuning of the phase difference between the two orthogonal field components. This tunability is further enhanced by the large confinement of the resonant electromagnetic fields within the MIM cavity. We show that for an appropriately chosen linearly polarized incident field, the polarization state of the reflected field at the target operation frequency can be continuously swept between the north and south pole of the Poincaré sphere. Using a rigorous Q-tensor model to simulate the LC electro-optic switching, we demonstrate that the enhanced light-matter interaction in the MIM resonant cavity allows the polarization converter to operate at driving voltages below 10 Volt and with millisecond switching times.

  19. Conformational landscape of an amyloid intra-cellular domain and Landau-Ginzburg-Wilson paradigm in protein dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Jin; He, Jianfeng, E-mail: Antti.Niemi@physics.uu.se, E-mail: hjf@bit.edu.cn [School of Physics, Beijing Institute of Technology, Beijing 100081 (China); Niemi, Antti J., E-mail: Antti.Niemi@physics.uu.se, E-mail: hjf@bit.edu.cn [School of Physics, Beijing Institute of Technology, Beijing 100081 (China); Department of Physics and Astronomy, Uppsala University, P.O. Box 803, S-75108 Uppsala (Sweden); Laboratoire de Mathematiques et Physique Theorique CNRS UMR 6083, Fédération Denis Poisson, Université de Tours, Parc de Grandmont, F37200 Tours (France)

    2016-07-28

    The Landau-Ginzburg-Wilson paradigm is proposed as a framework, to investigate the conformational landscape of intrinsically unstructured proteins. A universal Cα-trace Landau free energy is deduced from general symmetry considerations, with the ensuing all-atom structure modeled using publicly available reconstruction programs Pulchra and Scwrl. As an example, the conformational stability of an amyloid precursor protein intra-cellular domain (AICD) is inspected; the reference conformation is the crystallographic structure with code 3DXC in Protein Data Bank (PDB) that describes a heterodimer of AICD and a nuclear multi-domain adaptor protein Fe65. Those conformations of AICD that correspond to local or near-local minima of the Landau free energy are identified. For this, the response of the original 3DXC conformation to variations in the ambient temperature is investigated, using the Glauber algorithm. The conclusion is that in isolation the AICD conformation in 3DXC must be unstable. A family of degenerate conformations that minimise the Landau free energy is identified, and it is proposed that the native state of an isolated AICD is a superposition of these conformations. The results are fully in line with the presumed intrinsically unstructured character of isolated AICD and should provide a basis for a systematic analysis of AICD structure in future NMR experiments.

  20. Conformational landscape of an amyloid intra-cellular domain and Landau-Ginzburg-Wilson paradigm in protein dynamics

    International Nuclear Information System (INIS)

    Dai, Jin; He, Jianfeng; Niemi, Antti J.

    2016-01-01

    The Landau-Ginzburg-Wilson paradigm is proposed as a framework, to investigate the conformational landscape of intrinsically unstructured proteins. A universal Cα-trace Landau free energy is deduced from general symmetry considerations, with the ensuing all-atom structure modeled using publicly available reconstruction programs Pulchra and Scwrl. As an example, the conformational stability of an amyloid precursor protein intra-cellular domain (AICD) is inspected; the reference conformation is the crystallographic structure with code 3DXC in Protein Data Bank (PDB) that describes a heterodimer of AICD and a nuclear multi-domain adaptor protein Fe65. Those conformations of AICD that correspond to local or near-local minima of the Landau free energy are identified. For this, the response of the original 3DXC conformation to variations in the ambient temperature is investigated, using the Glauber algorithm. The conclusion is that in isolation the AICD conformation in 3DXC must be unstable. A family of degenerate conformations that minimise the Landau free energy is identified, and it is proposed that the native state of an isolated AICD is a superposition of these conformations. The results are fully in line with the presumed intrinsically unstructured character of isolated AICD and should provide a basis for a systematic analysis of AICD structure in future NMR experiments.

  1. Solid-phase glycan isolation for glycomics analysis.

    Science.gov (United States)

    Yang, Shuang; Zhang, Hui

    2012-12-01

    Glycosylation is one of the most significant protein PTMs. The biological activities of proteins are dramatically changed by the glycans associated with them. Thus, structural analysis of the glycans of glycoproteins in complex biological or clinical samples is critical in correlation with the functions of glycans with diseases. Profiling of glycans by HPLC-MS is a commonly used technique in analyzing glycan structures and quantifying their relative abundance in different biological systems. Methods relied on MS require isolation of glycans from negligible salts and other contaminant ions since salts and ions may interfere with the glycans, resulting in poor glycan ionization. To accomplish those objectives, glycan isolation and clean-up methods including SPE, liquid-phase extraction, chromatography, and electrophoresis have been developed. Traditionally, glycans are isolated from proteins or peptides using a combination of hydrophobic and hydrophilic columns: proteins and peptides remain on hydrophobic absorbent while glycans, salts, and other hydrophilic reagents are collected as flowthrough. The glycans in the flowthrough are then purified through graphite-activated carbon column by hydrophilic interaction LC. Yet, the drawback in these affinity-based approaches is nonspecific binding. As a result, chemical methods by hydrazide or oxime have been developed for solid-phase isolation of glycans with high specificity and yield. Combined with high-resolution MS, specific glycan isolation techniques provide tremendous potentials as useful tools for glycomics analysis. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. A mass conserving level set method for detailed numerical simulation of liquid atomization

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Kun; Shao, Changxiao [State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027 (China); Yang, Yue [State Key Laboratory of Turbulence and Complex Systems, Peking University, Beijing 100871 (China); Fan, Jianren, E-mail: fanjr@zju.edu.cn [State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027 (China)

    2015-10-01

    An improved mass conserving level set method for detailed numerical simulations of liquid atomization is developed to address the issue of mass loss in the existing level set method. This method introduces a mass remedy procedure based on the local curvature at the interface, and in principle, can ensure the absolute mass conservation of the liquid phase in the computational domain. Three benchmark cases, including Zalesak's disk, a drop deforming in a vortex field, and the binary drop head-on collision, are simulated to validate the present method, and the excellent agreement with exact solutions or experimental results is achieved. It is shown that the present method is able to capture the complex interface with second-order accuracy and negligible additional computational cost. The present method is then applied to study more complex flows, such as a drop impacting on a liquid film and the swirling liquid sheet atomization, which again, demonstrates the advantages of mass conservation and the capability to represent the interface accurately.

  3. Dynamics of liquid nitrogen cooling process of solid surface at wetting contact coefficient

    International Nuclear Information System (INIS)

    Smakulski, P; Pietrowicz, S

    2015-01-01

    Liquid cryogens cooling by direct contact is very often used as a method for decreasing the temperature of electronic devices or equipment i.e. HTS cables. Somehow, cooldown process conducted in that way could not be optimized, because of cryogen pool boiling characteristic and low value of the heat transfer coefficient. One of the possibilities to increase the efficiency of heat transfer, as well as the efficiency of cooling itself, it is to use a spray cooling method. The paper shows dynamics analysis of liquid nitrogen cooling solid surface process. The model of heat transfer for the single droplet of liquid nitrogen, which hits on a flat and smooth surface with respect to the different Weber numbers, is shown. Temperature profiles in calculation domains are presented, as well as the required cooling time. The numerical calculations are performed for different initial and boundary conditions, to study how the wetting contact coefficient is changing, and how it contributed to heat transfer between solid and liquid cryogen. (paper)

  4. A room-temperature liquid calorimeter prototype for the SSC

    International Nuclear Information System (INIS)

    Brandenburg, G.W.; Geer, S.H.; Oliver, J.; Sadowski, E.; Theriot, D.

    1990-01-01

    Calorimeters will be an extremely important part of SSC detectors as they have been in existing collider detectors. The main issues that need to be addressed are: (1) energy resolution of jets and electrons, (2) segmentation, (3) hermiticity, (4) response time, and (5) radiation resistance. An attractive possibility on all these counts is the use of room-temperature liquids together with uranium, as pioneered by UA1. The authors are planning a prototype calorimeter which consists of a sealed vessel containing both the radiator plates and the readout pads. This geometry has been appropriately named the swimming pool design. The general mechanical starting point is similar to the SLD liquid argon calorimeters. The points they wish to address are the following: (1) Simple and reliable modular construction techniques, (2) Satisfactory electrical connections with minimal geometric impact, (3) The necessity of isolating radiator plates and liquid to maintain purity, (4) What materials can be immersed without compromising the liquid purity. The design and construction of the swimming pool electromagnetic calorimeter prototype is being carried out at the Harvard High Energy Physics Laboratory. This is one of the first attempts to build a full-scale prototype of such a design

  5. The PH Domain of PDK1 Exhibits a Novel, Phospho-Regulated Monomer-Dimer Equilibrium With Important Implications for Kinase Domain Activation: Single Molecule and Ensemble Studies†

    Science.gov (United States)

    Ziemba, Brian P.; Pilling, Carissa; Calleja, Véronique; Larijani, Banafshé; Falke, Joseph J.

    2013-01-01

    Phosphoinositide-Dependent Kinase-1 (PDK1) is an essential master kinase recruited to the plasma membrane by the binding of its C-terminal PH domain to the signaling lipid phosphatidylinositol-3,4-5-trisphosphate (PIP3). Membrane binding leads to PDK1 phospho-activation, but despite the central role of PDK1 in signaling and cancer biology this activation mechanism remains poorly understood. PDK1 has been shown to exist as a dimer in cells, and one crystal structure of its isolated PH domain exhibits a putative dimer interface. It has been proposed that phosphorylation of PH domain residue T513 (or the phospho-mimetic T513E mutation) may regulate a novel PH domain dimer-monomer equilibrium, thereby converting an inactive PDK1 dimer to an active monomer. However, the oligomeric state(s) of the PH domain on the membrane have not yet been determined, nor whether a negative charge at position 513 is sufficient to regulate its oligomeric state. The present study investigates the binding of purified WT and T513E PDK1 PH domains to lipid bilayers containing the PIP3 target lipid, using both single molecule and ensemble measurements. Single molecule analysis of the brightness of fluorescent PH domain shows that the PIP3-bound WT PH domain on membranes is predominantly dimeric, while the PIP3-bound T513E PH domain is monomeric, demonstrating that negative charge at the T513 position is sufficient to dissociate the PH domain dimer and is thus likely to play a central role in PDK1 monomerization and activation. Single molecule analysis of 2-D diffusion of PH domain-PIP3 complexes reveals that the dimeric WT PH domain diffuses at the same rate a single lipid molecule, indicating that only one of its two PIP3 binding sites is occupied and there is little protein penetration into the bilayer as observed for other PH domains. The 2-D diffusion of T513E PH domain is slower, suggesting the negative charge disrupts local structure in a way that enables greater protein insertion into

  6. Alpha liquid scintillation counting: past, present, and future

    International Nuclear Information System (INIS)

    McDowell, W.J.

    1979-01-01

    Beta liquid scintillation counting has been used for about 30 years, and its effectiveness for alpha particles has been known for almost that long; however, the technique has not been widely applied to alpha particle detection because of poor energy resolution, high background, and variable interference from beta and gamma radiation. Beginning with the work of Horrocks in the early 1960s, improvements in energy resolution and background rejection have been made. Further developments at Oak Ridge National Laboratory over the past 10 to 12 years have resulted in improved methods of sample preparation (using liquid-liquid extraction methods to isolate the sample and introduce it into the scintillator) and better instrumentation, including electronic rejection of beta and gamma pulses. Energy resolutions of 200- to 300-keV FWHM and background counts of 0.01 cpm are now routine. Alpha liquid scintillation spectrometry is now suitable for a wide range of applications, from the accurate quantitative determination of relatively large amounts of known nuclides in laboratory-generated samples to the detection and identification of very small, subpicocurie amounts of alpha emitters in environmental-type samples. Suitable nuclide separation procedures, sample preparation methods, and instrument configurations are outlined for a variety of analyses

  7. Effect of media composition, including gelling agents, on isolation of previously uncultured rumen bacteria.

    Science.gov (United States)

    Nyonyo, T; Shinkai, T; Tajima, A; Mitsumori, M

    2013-01-01

    The aim of this study was to develop novel anaerobic media using gellan gum for the isolation of previously uncultured rumen bacteria. Four anaerobic media, a basal liquid medium (BM) with agar (A-BM), a modified BM (MBM) with agar (A-MBM), an MBM with phytagel (P-MBM) and an MBM with gelrite (G-MBM) were used for the isolation of rumen bacteria and evaluated for the growth of previously uncultured rumen bacteria. Of the 214 isolates composed of 144 OTUs, 103 isolates (83 OTUs) were previously uncultured rumen bacteria. Most of the previously uncultured strains were obtained from A-MBM, G-MBM and P-MBM, but the predominant cultural members, isolated from each medium, differed. A-MBM and G-MBM showed significantly higher numbers of different OTUs derived from isolates than A-BM (P rumen bacteria were isolated from all media used, the ratio of previously uncultured bacteria to total isolates was increased in A-MBM, P-MBM and G-MBM. © 2012 The Society for Applied Microbiology.

  8. Tunable Channel Drop Filter in a Two-Dimensional Photonic Crystal Modulated by a Nematic Liquid Crystal

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available Photonic crystals (PCs have many potential applications because of their ability to control light-wave propagation and because PC-based waveguides may be integrated into optical circuits. We propose a novel tunable PC channel drop filter based on nematic liquid crystals and investigate its properties numerically by using the finite-difference time-domain (FDTD method. The refractive indices of liquid crystals can be actively modulated after infiltrating nematic liquid crystals into the microcavity in PC waveguides with square lattices. Then we can control light propagation in a PC waveguide. We analyze the Q -factors and resonance frequencies of a tunable PC channel drop filter by considering various indices modulation of liquid crystals. The novel component can be used as wavelength division multiplexing in photonic integrated circuits.

  9. Sequence diversity and natural selection at domain I of the apical membrane antigen 1 among Indian Plasmodium falciparum populations

    Directory of Open Access Journals (Sweden)

    Kumar Ashwani

    2007-11-01

    Full Text Available Abstract Background The Plasmodium falciparum apical membrane antigen 1 (AMA1 is a leading malaria vaccine candidate antigen. The complete AMA1 protein is comprised of three domains where domain I exhibits high sequence polymorphism and is thus named as the hyper-variable region (HVR. The present study describes the extent of genetic polymorphism and natural selection at domain I of the ama1 gene among Indian P. falciparum isolates. Methods The part of the ama1 gene covering domain I was PCR amplified and sequenced from 157 P. falciparum isolates collected from five different geographical regions of India. Statistical and phylogenetic analyses of the sequences were done using DnaSP ver. 4. 10. 9 and MEGA version 3.0 packages. Results A total of 57 AMA1 haplotypes were observed among 157 isolates sequenced. Forty-six of these 57 haplotypes are being reported here for the first time. The parasites collected from the high malaria transmission areas (Assam, Orissa, and Andaman and Nicobar Islands showed more haplotypes (H and nucleotide diversity π as compared to low malaria transmission areas (Uttar Pradesh and Goa. The comparison of all five Indian P. falciparum subpopulations indicated moderate level of genetic differentiation and limited gene flow (Fixation index ranging from 0.048 to 0.13 between populations. The difference between rates of non-synonymous and synonymous mutations, Tajima's D and McDonald-Kreitman test statistics suggested that the diversity at domain I of the AMA1 antigen is due to positive natural selection. The minimum recombination events were also high indicating the possible role of recombination in generating AMA1 allelic diversity. Conclusion The level of genetic diversity and diversifying selection were higher in Assam, Orissa, and Andaman and Nicobar Islands populations as compared to Uttar Pradesh and Goa. The amounts of gene flow among these populations were moderate. The data reported here will be valuable for the

  10. Target materials for exotic ISOL beams

    CERN Document Server

    Gottberg, A

    2016-01-01

    The demand for intensity, purity, reliability and availability of short-lived isotopes far from stability is steadily high, and considerably exceeding the supply. In many cases the ISOL (Isotope Separation On-Line) method can provide beams of high intensity and purity. Limitations in terms of accessible chemical species and minimum half-life are driven mainly by chemical reactions and physical processes inside of the thick target. A wide range of materials are in use, ranging from thin metallic foils and liquids to refractory ceramics, while poly-phasic mixed uranium carbides have become the reference target material for most ISOL facilities world-wide. Target material research and development is often complex and especially important post-irradiation analyses are hindered by the high intrinsic radiotoxicity of these materials. However, recent achievements have proven that these investigations are possible if the effort of different facilities is combined, leading to the development of new material matrices t...

  11. Multistability in planar liquid crystal wells

    KAUST Repository

    Luo, Chong

    2012-06-08

    A planar bistable liquid crystal device, reported in Tsakonas, is modeled within the Landau-de Gennes theory for nematic liquid crystals. This planar device consists of an array of square micrometer-sized wells. We obtain six different classes of equilibrium profiles and these profiles are classified as diagonal or rotated solutions. In the strong anchoring case, we propose a Dirichlet boundary condition that mimics the experimentally imposed tangent boundary conditions. In the weak anchoring case, we present a suitable surface energy and study the multiplicity of solutions as a function of the anchoring strength. We find that diagonal solutions exist for all values of the anchoring strength W≥0, while rotated solutions only exist for W≥W c>0, where W c is a critical anchoring strength that has been computed numerically. We propose a dynamic model for the switching mechanisms based on only dielectric effects. For sufficiently strong external electric fields, we numerically demonstrate diagonal-to-rotated and rotated-to-diagonal switching by allowing for variable anchoring strength across the domain boundary. © 2012 American Physical Society.

  12. Multistability in planar liquid crystal wells

    KAUST Repository

    Luo, Chong; Majumdar, Apala; Erban, Radek

    2012-01-01

    A planar bistable liquid crystal device, reported in Tsakonas, is modeled within the Landau-de Gennes theory for nematic liquid crystals. This planar device consists of an array of square micrometer-sized wells. We obtain six different classes of equilibrium profiles and these profiles are classified as diagonal or rotated solutions. In the strong anchoring case, we propose a Dirichlet boundary condition that mimics the experimentally imposed tangent boundary conditions. In the weak anchoring case, we present a suitable surface energy and study the multiplicity of solutions as a function of the anchoring strength. We find that diagonal solutions exist for all values of the anchoring strength W≥0, while rotated solutions only exist for W≥W c>0, where W c is a critical anchoring strength that has been computed numerically. We propose a dynamic model for the switching mechanisms based on only dielectric effects. For sufficiently strong external electric fields, we numerically demonstrate diagonal-to-rotated and rotated-to-diagonal switching by allowing for variable anchoring strength across the domain boundary. © 2012 American Physical Society.

  13. Phase change events of volatile liquid perfluorocarbon contrast agents produce unique acoustic signatures

    International Nuclear Information System (INIS)

    Sheeran, Paul S; Dayton, Paul A; Matsunaga, Terry O

    2014-01-01

    Phase-change contrast agents (PCCAs) provide a dynamic platform to approach problems in medical ultrasound (US). Upon US-mediated activation, the liquid core vaporizes and expands to produce a gas bubble ideal for US imaging and therapy. In this study, we demonstrate through high-speed video microscopy and US interrogation that PCCAs composed of highly volatile perfluorocarbons (PFCs) exhibit unique acoustic behavior that can be detected and differentiated from standard microbubble contrast agents. Experimental results show that when activated with short pulses PCCAs will over-expand and undergo unforced radial oscillation while settling to a final bubble diameter. The size-dependent oscillation phenomenon generates a unique acoustic signal that can be passively detected in both time and frequency domain using confocal piston transducers with an ‘activate high’ (8 MHz, 2 cycles), ‘listen low’ (1 MHz) scheme. Results show that the magnitude of the acoustic ‘signature’ increases as PFC boiling point decreases. By using a band-limited spectral processing technique, the droplet signals can be isolated from controls and used to build experimental relationships between concentration and vaporization pressure. The techniques shown here may be useful for physical studies as well as development of droplet-specific imaging techniques. (paper)

  14. Methods of hydrolyzing a cellulose using halophilic, thermostable and ionic liquids tolerant cellulases

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Tao; Datta, Supratim; Simmons, Blake A.; Rubin, Edward M.

    2018-01-09

    The present invention provides for an isolated or recombinant polypeptide comprising an amino acid sequence having at least 70% identity with the amino acid sequence of a Halorhabdus utahensis cellulase, such as Hu-CBH1, wherein said amino acid sequence has a halophilic thermostable and/or thermophilic cellobiohydrolase (CBH) activity. In some embodiments, the polypeptide has a CBH activity that is resistant to up to about 20% of ionic liquids. The present invention also provides for compositions comprising and methods using the isolated or recombinant polypeptide.

  15. Synthesis of hexavalent molybdenum formo- and aceto-hydroxamates and deferoxamine via liquid-liquid metal partitioning

    Energy Technology Data Exchange (ETDEWEB)

    Breshears, Andrew T.; Brown, M. Alex; Bloom, Ira; Barnes, Charles L.; Gelis, Artem V.

    2018-03-01

    We report a new method of crystal growth and synthesis based on liquid-liquid partitioning that allows for isolation and in-depth characterization of molybdenyl bis(formohydroxamate), Mo-FHA, molybdenyl bis(acetohydroxamate), Mo-AHA, and molybdenyl deferoxamine, Mo-DFO, for the first time. This novel approach affords shorter crystal growth time (hourly timeframe) without sacrificing crystal size or integrity when other methods of crystallization were unsuccessful. All three Mo complexes are characterized in solution via FTIR, NMR, UV-vis, and EXAFS spectroscopy. Mo-AHA and Mo-FHA structures are resolved by single crystal X-ray diffraction. Using the molybdenyl hydroxamate structural information, the speciation of Mo in a siderophore complex (Mo-DFO) is determined via complimentary spectroscopic methods and confirmed by DFT calculations. ESI-MS verifies that a complex of 1:1 molybdenum to deferoxamine is present in solution. Additionally, the Mo solution speciation in the precursor organic phase, MoO2(NO3)2HEH[EHP]2 (where HEH[EHP] is 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester), is characterized by FTIR and EXAFS spectroscopy as well as DFT calculations.

  16. DNA binding and unwinding by Hel308 helicase requires dual functions of a winged helix domain.

    Science.gov (United States)

    Northall, Sarah J; Buckley, Ryan; Jones, Nathan; Penedo, J Carlos; Soultanas, Panos; Bolt, Edward L

    2017-09-01

    Hel308 helicases promote genome stability linked to DNA replication in archaea, and have homologues in metazoans. In the crystal structure of archaeal Hel308 bound to a tailed DNA duplex, core helicase domains encircle single-stranded DNA (ssDNA) in a "ratchet" for directional translocation. A winged helix domain (WHD) is also present, but its function is mysterious. We investigated the WHD in full-length Hel308, identifying that mutations in a solvent exposed α-helix resulted in reduced DNA binding and unwinding activities. When isolated from the rest of Hel308, the WHD protein alone bound to duplex DNA but not ssDNA, and DNA binding by WHD protein was abolished by the same mutations as were analyzed in full-length Hel308. Isolated WHD from a human Hel308 homologue (HelQ) also bound to duplex DNA. By disrupting the interface between the Hel308 WHD and a RecA-like domain, a topology typical of Ski2 helicases, we show that this is crucial for ATPase and helicase activities. The data suggest a model in which the WHD promotes activity of Hel308 directly, through binding to duplex DNA that is distinct from ssDNA binding by core helicase, and indirectly through interaction with the RecA-like domain. We propose how the WHD may contribute to ssDNA translocation, resulting in DNA helicase activity or in removal of other DNA bound proteins by "reeling" ssDNA. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Liquidity risk and contagion for liquid funds

    OpenAIRE

    Darolles , Serge; Dudek , Jeremy; Le Fol , Gaëlle

    2014-01-01

    Fund managers face liquidity problems but they have to distinguish the market liquidity risk implied by their assets and the funding liquidity risk. This latter is due to both the liquidity mismatch between assets and liabilities and the redemption risk due to the possible outflows from clients. The main contribution of this paper is the analysis of contagion looking at common market liquidity problems to detect funding liquidity problems. Using the CDS Bond Spread basis as a liquidity indica...

  18. A novel paradigm for high isolation in multiple antenna systems with user's influence

    DEFF Research Database (Denmark)

    Pelosi, Mauro; Pedersen, Gert Frølund; Knudsen, Mikael Bergholz

    2010-01-01

    (UMTS) bands are investigated, showing also the influence of different hand phantoms in average use trough Finite-Difference TimeDomain (FDTD) simulations. It is confirmed that the way a mobile phone is held is very important in determining the amount of absorption loss, detuning and antenna isolation...

  19. Study on three dimensional seismic isolation system

    International Nuclear Information System (INIS)

    Morishita, Masaki; Kitamura, Seiji

    2003-01-01

    Japan Nuclear Cycle Development Institute (JNC) and Japan Atomic Power Company (JAPC) launched joint research programs on structural design and three-dimensional seismic isolation technologies, as part of the supporting R and D activities for the feasibility studies on commercialized fast breeder reactor cycle systems. A research project by JAPC under the auspices of the Ministry of Economy, Trade, and Industry (METI) with technical support by JNC is included in this joint study. This report contains the results of the research on the three-dimensional seismic isolation technologies, and the results of this year's study are summarized in the following five aspects. (1) Study on Earthquake Condition for Developing 3-dimensional Base Isolation System. The case study S2 is one of the maximum ground motions, of which the records were investigated up to this time. But a few observed near the fault exceed the case study S2 in the long period domain, depending on the fault length and conditions. Generally it is appropriate that the response spectra ratio (vertical/horizontal) is 0.6. (2) Performance Requirement for 3-dimensional Base Isolation System and Devices. Although the integrity map of main equipment/piping dominate the design criteria for the 3-dimensional base isolation system, the combined integrity map is the same as those of FY 2000, which are under fv=1Hz and over hv=20%. (3) Developing Targets and Schedule for 3-dimensional Isolation Technology. The target items for 3-dimensional base isolation system were rearranged into a table, and developing items to be examined concerning the device were also adjusted. A development plan until FY 2009 was made from the viewpoint of realization and establishment of a design guideline on 3-dimensional base isolation system. (4) Study on 3-dimensional Entire Building Base Isolation System. Three ideas among six ideas that had been proposed in FY2001, i.e., '3-dimensional base isolation system incorporating hydraulic

  20. From Funding Liquidity to Market Liquidity

    DEFF Research Database (Denmark)

    Dick-Nielsen, Jens; Lund, Jesper; Gyntelberg, Jacob

    This paper shows empirically that funding liquidity drives market liquidity. As it becomes harder to secure term funding in the money markets, liquidity deteriorates in the Danish bond market. We show that the first principal component of bond market liquidity is driven by the market makers...... for other European government bonds using MTS data. The findings suggest that regulatory bond based liquidity buffers for banks will have limited effectiveness....

  1. Domain Engineering

    Science.gov (United States)

    Bjørner, Dines

    Before software can be designed we must know its requirements. Before requirements can be expressed we must understand the domain. So it follows, from our dogma, that we must first establish precise descriptions of domains; then, from such descriptions, “derive” at least domain and interface requirements; and from those and machine requirements design the software, or, more generally, the computing systems.

  2. Crystallization and preliminary crystallographic analysis of the transpeptidase domain of penicillin-binding protein 2B from Streptococcus pneumoniae

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Mototsugu, E-mail: mototsugu-yamada@meiji.co.jp; Watanabe, Takashi; Baba, Nobuyoshi; Miyara, Takako; Saito, Jun; Takeuchi, Yasuo [Pharmaceutical Research Center, Meiji Seika Kaisha Ltd, 760 Morooka-cho, Kohoku-ku, Yokohama 222-8567 (Japan)

    2008-04-01

    The selenomethionyl-substituted transpeptidase domain of penicillin-binding protein (PBP) 2B from S. pneumoniae was isolated from a limited proteolysis digest of the soluble form of recombinant PBP 2B and then crystallized. MAD data were collected to 2.4 Å resolution. Penicillin-binding protein (PBP) 2B from Streptococcus pneumoniae catalyzes the cross-linking of peptidoglycan precursors that occurs during bacterial cell-wall biosynthesis. A selenomethionyl (SeMet) substituted PBP 2B transpeptidase domain was isolated from a limited proteolysis digest of a soluble form of recombinant PBP 2B and then crystallized. The crystals belonged to space group P4{sub 3}2{sub 1}2, with unit-cell parameters a = b = 86.39, c = 143.27 Å. Diffraction data were collected to 2.4 Å resolution using the BL32B2 beamline at SPring-8. The asymmetric unit contains one protein molecule and 63.7% solvent.

  3. Crystallization and preliminary crystallographic analysis of the transpeptidase domain of penicillin-binding protein 2B from Streptococcus pneumoniae

    International Nuclear Information System (INIS)

    Yamada, Mototsugu; Watanabe, Takashi; Baba, Nobuyoshi; Miyara, Takako; Saito, Jun; Takeuchi, Yasuo

    2008-01-01

    The selenomethionyl-substituted transpeptidase domain of penicillin-binding protein (PBP) 2B from S. pneumoniae was isolated from a limited proteolysis digest of the soluble form of recombinant PBP 2B and then crystallized. MAD data were collected to 2.4 Å resolution. Penicillin-binding protein (PBP) 2B from Streptococcus pneumoniae catalyzes the cross-linking of peptidoglycan precursors that occurs during bacterial cell-wall biosynthesis. A selenomethionyl (SeMet) substituted PBP 2B transpeptidase domain was isolated from a limited proteolysis digest of a soluble form of recombinant PBP 2B and then crystallized. The crystals belonged to space group P4 3 2 1 2, with unit-cell parameters a = b = 86.39, c = 143.27 Å. Diffraction data were collected to 2.4 Å resolution using the BL32B2 beamline at SPring-8. The asymmetric unit contains one protein molecule and 63.7% solvent

  4. Isolation and identification of fungi from a meju contaminated with aflatoxins.

    Science.gov (United States)

    Jung, Yu Jung; Chung, Soo Hyun; Lee, Hyo Ku; Chun, Hyang Sook; Hong, Seung Beom

    2012-12-01

    A home-made meju sample contaminated naturally with aflatoxins was used for isolation of fungal strains. Overall, 230 fungal isolates were obtained on dichloran rosebengal chloramphenicol (DRBC) and dichloran 18% glycerol (DG18) agar plates. Morphological characteristics and molecular analysis of a partial beta-tubulin gene and the internal transcribed spacer (ITS) of rDNA were used for the identification of the isolates. The fungal isolates were divided into 7 genera: Aspergillus, Eurotium, Penicillium, Eupenicillium, Mucor, Lichtheimia, and Curvularia. Three strains from 56 isolates of the A. oryzae/flavus group were found to be aflatoxigenic A. flavus, by the presence of the aflatoxin biosynthesis genes and confirmatory aflatoxin production by high-performance liquid chromatography (HPLC). The predominant isolate from DRBC plates was A. oryzae (42 strains, 36.2%), whereas that from DG18 was A. candidus (61 strains, 53.5%). Out of the 230 isolates, the most common species was A. candidus (34.3%) followed by A. oryzae (22.2%), Mucor circinelloides (13.0%), P. polonicum (10.0%), A. tubingensis (4.8%), and L. ramosa (3.5%). A. flavus and E. chevalieri presented occurrence levels of 2.2%, respectively. The remaining isolates of A. unguis, P. oxalicum, Eupenicillium cinnamopurpureum, A. acidus, E. rubrum, P. chrysogenum, M. racemosus, and C. inaequalis had lower occurrence levels of < 2.0%.

  5. Antimicrobial susceptibility testing of Mycoplasma hyosynoviae isolated from pigs during 1968 to 1971 and during 1995 and 1996

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Friis, N. F.

    1998-01-01

    This study was conducted to compare the Minimal Inhibitory Concentrations (MICs) for enrofloxacin, lincomycin, tetracycline, tiamulin and tylosin, of Mycoplasma hyosynoviae, isolated from pigs at notably different intervals (1968-71 and 1995-96). Each group comprised 21 low passage isolates...... and a Danish reference strain (M60) and the type strain (S16). MICs were determined in liquid medium with both initial and final readings. Enrofloxacin, lincomycin, tetracycline and tiamulin were active against all isolates, and tiamulin showed the highest activity. For tylosin all the isolates from 1968......-71 were highly susceptible, whereas the isolates from 1995-96 could be divided into a highly susceptible (nine isolates) and relatively resistant (12 isolates) group. This difference between old and new strains was statistically significant (p=0.0000415). The remaining agents, enrofloxacin, lincomycin...

  6. Isolation and quantification of volatiles in fish by dynamic headspace sampling and mass spectrometry

    DEFF Research Database (Denmark)

    Refsgaard, Hanne; Haahr, Anne-Mette; Jensen, Benny

    1999-01-01

    A dynamic headspace sampling method for isolation of volatiles in fish has been developed. The sample preparation involved freezing of fish tissue in liquid nitrogen, pulverizing the tissue, and sampling of volatiles from an aqueous slurry of the fish powder. Similar volatile patterns were...

  7. Diagnostic performance of automated liquid culture and molecular line probe assay in smear-negative pulmonary tuberculosis.

    Science.gov (United States)

    Kotwal, Aarti; Biswas, Debasis; Raghuvanshi, Shailendra; Sindhwani, Girish; Kakati, Barnali; Sharma, Shweta

    2017-04-01

    The diagnosis of smear-negative pulmonary tuberculosis (PTB) is particularly challenging, and automated liquid culture and molecular line probe assays (LPA) may prove particularly useful. The objective of our study was to evaluate the diagnostic potential of automated liquid culture (ALC) technology and commercial LPA in sputum smear-negative PTB suspects. Spot sputum samples were collected from 145 chest-symptomatic smear-negative patients and subjected to ALC, direct drug susceptibility test (DST) testing and LPA, as per manufacturers' instructions. A diagnostic yield of 26.2% was observed among sputum smear-negative TB suspects with 47.4% of the culture isolates being either INH- and/or rifampicin-resistant. Complete agreement was observed between the results of ALC assay and LPA except for two isolates which demonstrated sensitivity to INH and rifampicin at direct DST but were rifampicin-resistant in LPA. Two novel mutations were also detected among the multidrug isolates by LPA. In view of the diagnostic challenges associated with the diagnosis of TB in sputum smear-negative patients, our study demonstrates the applicability of ALC and LPA in establishing diagnostic evidence of TB.

  8. ‘Tidjanibacter massiliensis’ gen. nov., sp. nov., a new bacterial species isolated from human colon

    Directory of Open Access Journals (Sweden)

    M. Mailhe

    2017-05-01

    Full Text Available We report the summary of main characteristics of Tidjanibacter massiliensis strain Marseille-P3084T, a new bacterial species isolated from the liquid sample of the colon of a patient with a history of irritable bowel syndrome.

  9. A method for producing liquid paraffin

    Energy Technology Data Exchange (ETDEWEB)

    Dorodnova, V.S.; Martynenko, A.G.; Pereverzev, A.N.

    1983-01-01

    In the known method (Sp) for producing liquid paraffins (ZhP) through processing an oil fraction by crystalline carbamide in the presence of a solvent with subsequent removal of the formed complex (Km) of KA with the liquid paraffins from the deparaffinized product, staged washing and decomposition of the complex with isolation of the liquid paraffins, in order to increase the output of liquid paraffin and to improve its quality, beta,beta'-dichlorethyl ether (khloreks) in a mixture with methylethyl ketone (MEK) or methylisobutyl ketone in a ratio of 1 is used as the solvent, the processing by the crystalline carbamide is conducted with the addition of 180 to 260 percent solvent to raw material (Sr) and the washing of the composition is conducted by a solvent in the first stage and by methylethyl ketone or methylisobutyl ketone in the second stage. The crystalline carbamide for the complex formation is taken in a conversion of 60 to 70 percent for the raw material for observing the raw material to solvent ratio of from 1 to 1.8 to 2.6 to 0.6 to 0.6. The temperature in the zone of formation of the complex is maintained at 5 to 35 degrees. The presence of beta,beta'-dichlorethyl ether, which has high selectivity relative to aromatic hydrocarbons (ArU) and to resinous compounds provides for a sharp reduction in the adsorption of the undesired components on the surface of the granules of the complex and the crystalline carbamide and to a reduction in the portion of the alkylaromatic hydrocarbons (UV) extracted into the complex, which leads to a substantial improvement in the quality of the obtained liquid paraffins.

  10. Isolation and quantitation of metallothionein isoforms using reversed-phase high-performance liquid chromatography

    International Nuclear Information System (INIS)

    Richards, M.P.; Darcey, S.E.; Steele, N.C.

    1986-01-01

    Reversed-phase HPLC (RP-HPLC) was used to isolate and quantify metallothionein (MT) isoforms from a variety of animal species and tissues. Separations were performed on C 18 radially compressed cartridge columns, eluted with a 2-step linear gradient of acetonitrile in 10 mM sodium phosphate, pH 7.0. Isoforms were detected by UV absorbance (214 nm) and by on-line interfacing with an atomic absorption spectrophotometer (HPLC-AA) to determine bound Zn, Cd and Cu. Rabbit liver and horse kidney MT's exhibited 7 distinct peaks on RP-HPLC, 2 of which were predominant (MT1 and 2). Pig liver and kidney MT2 yielded 2 subspecies on RP-HPLC, while MT1 yielded a single peak. Avian liver MT was unique from mammalian MT's in that MT2 was about tenfold more abundant than MT1. RP-HPLC and HPLC-AA were used to isolate and quantitate MT isoforms and their Zn content directly from cytosol. Quantitation was achieved by peak area integration and extrapolation from a standard curve of purified avian liver MT2. Both RP-HPLC and HPLC-AA had a lower detection limit of 1 + g of peptide and .1 μg of Zn. Recoveries (92-98%) were determined with labeled ( 35 S) MT and MT of known Zn content. Cytoplasmic MT-Zn in avian embryo hepatocytes cultured with added Zn was quantitated using HPLC-AA. In conclusion, both RP-HPLC and HPLC-AA are rapid and powerful separation techniques for the isolation, quantitation and characterization of the isoproteins comprising the MT gene family

  11. Experimental (solid + liquid) or (liquid + liquid) phase equilibria of (amine + nitrile) binary mixtures

    International Nuclear Information System (INIS)

    Domanska, Urszula; Marciniak, Malgorzata

    2007-01-01

    (Solid + liquid) phase diagrams have been determined for (hexylamine, or octylamine, or 1,3-diaminopropane + acetonitrile) mixtures. Simple eutectic systems have been observed in these mixtures. (Liquid + liquid) phase diagrams have been determined for (octylamine, or decylamine + propanenitrile, or + butanenitrile) mixtures. Mixtures with propanenitrile and butanenitrile show immiscibility in the liquid phase with an upper critical solution temperature, UCST. (Solid + liquid) phase diagrams have been correlated using NRTL, NRTL 1, Wilson and UNIQUAC equations. (Liquid + liquid) phase diagrams have been correlated using NRTL equation

  12. Pentavalent single-domain antibodies reduce Campylobacter jejuni motility and colonization in chickens.

    Directory of Open Access Journals (Sweden)

    Ali Riazi

    Full Text Available Campylobacter jejuni is the leading cause of bacterial foodborne illness in the world, with symptoms ranging from acute diarrhea to severe neurological disorders. Contaminated poultry meat is a major source of C. jejuni infection, and therefore, strategies to reduce this organism in poultry, are expected to reduce the incidence of Campylobacter-associated diseases. We have investigated whether oral administration of C. jejuni-specific single-domain antibodies would reduce bacterial colonization levels in chickens. Llama single-domain antibodies specific for C. jejuni were isolated from a phage display library generated from the heavy chain IgG variable domain repertoire of a llama immunized with C. jejuni flagella. Two flagella-specific single-domain antibodies were pentamerized to yield high avidity antibodies capable of multivalent binding to the target antigen. When administered orally to C. jejuni-infected two-day old chicks, the pentabodies significantly reduced C. jejuni colonization in the ceca. In vitro, the motility of the bacteria was also reduced in the presence of the flagella-specific pentabodies, suggesting the mechanism of action is through either direct interference with flagellar motility or antibody-mediated aggregation. Fluorescent microscopy and Western blot analyses revealed specific binding of the anti-flagella pentabodies to the C. jejuni flagellin.

  13. Requirement of Sequences outside the Conserved Kinase Domain of Fission Yeast Rad3p for Checkpoint Control

    Science.gov (United States)

    Chapman, Carolyn Riley; Evans, Sarah Tyler; Carr, Antony M.; Enoch, Tamar

    1999-01-01

    The fission yeast Rad3p checkpoint protein is a member of the phosphatidylinositol 3-kinase-related family of protein kinases, which includes human ATMp. Mutation of the ATM gene is responsible for the disease ataxia-telangiectasia. The kinase domain of Rad3p has previously been shown to be essential for function. Here, we show that although this domain is necessary, it is not sufficient, because the isolated kinase domain does not have kinase activity in vitro and cannot complement a rad3 deletion strain. Using dominant negative alleles of rad3, we have identified two sites N-terminal to the conserved kinase domain that are essential for Rad3p function. One of these sites is the putative leucine zipper, which is conserved in other phosphatidylinositol 3-kinase-related family members. The other is a novel motif, which may also mediate Rad3p protein–protein interactions. PMID:10512862

  14. Emergence of the Coherent Structure of Liquid Water

    Directory of Open Access Journals (Sweden)

    Ivan Bono

    2012-07-01

    Full Text Available We examine in some detail the interaction of water molecules with the radiative electromagnetic field and find the existence of phase transitions from the vapor phase to a condensed phase where all molecules oscillate in unison, in tune with a self-trapped electromagnetic field within extended mesoscopic space regions (Coherence Domains. The properties of such a condensed phase are examined and found to be compatible with the phenomenological properties of liquid water. In particular, the observed value of critical density is calculated with good accuracy.

  15. Isolation of saprophytic Leptospira spp. from a selected environmental water source of Argentina.

    Science.gov (United States)

    Scialfa, Exequiel; Grune, Sylvia; Brihuega, Bibiana; Aguirre, Pablo; Rivero, Marina

    2017-11-29

    Ten Leptospira spp. strains were isolated from water samples from Nievas stream, Olavarría, Buenos Aires province (Argentina). The isolates showed the typical motility and morphology of the genus Leptospira under dark field microscopy, developing in liquid EMJH medium after eight days of incubation at 13°C and 30°C. All isolates were negative by the Multiple Locus Variable Number Tandem Repeat Analysis (MLVA). Molecular identification by 16S rRNA gene sequencing identified all isolates as nonpathogenic leptospires. Four isolates showed a genetic profile identical to that of the reference strain Leptospira biflexa serovar Patoc, and six isolates revealed sequence similarities within the 97-98% range, closely related to Leptospira yanagawae and Leptospira meyeri, respectively. Strains ScialfaASA42, ScialfaASA45, ScialfaASA44, ScialfaASA47, ScialfaASA49, ScialfaASA50 and ScialfaASA51 possibly represent a novel species of the genus Leptospira. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  16. Bispecific engineered antibody domains (nanoantibodies that interact noncompetitively with an HIV-1 neutralizing epitope and FcRn.

    Directory of Open Access Journals (Sweden)

    Rui Gong

    Full Text Available Libraries based on an isolated human immunoglobulin G1 (IgG1 constant domain 2 (CH2 have been previously diversified by random mutagenesis. However, native isolated CH2 is not very stable and the generation of many mutations could lead to an increase in immunogenicity. Recently, we demonstrated that engineering an additional disulfide bond and removing seven N-terminal residues results in an engineered antibody domain (eAd (m01s with highly increased stability and enhanced binding to human neonatal Fc receptor (FcRn (Gong et al, JBC, 2009 and 2011. We and others have also previously shown that grafting of the heavy chain complementarity region 3 (CDR-H3 (H3 onto cognate positions of the variable domain leads to highly diversified libraries from which a number of binders to various antigens have been selected. However, grafting of H3s to non-cognate positions in constant domains results in additional residues at the junctions of H3s and the CH2 framework. Here we describe a new method based on multi-step PCR that allows the precise replacement of loop FG (no changes in its flanking sequences by human H3s from another library. Using this method and limited mutagenesis of loops BC and DE we generated an eAd phage-displayed library. Panning of this library against an HIV-1 gp41 MPER peptide resulted in selection of a binder, m2a1, which neutralized HIV-1 isolates from different clades with modest activity and retained the m01s capability of binding to FcRn. This result provides a proof of concept that CH2-based antigen binders that also mimic to certain extent other functions of full-size antibodies (binding to FcRn can be generated; we have previously hypothesized that such binders can be made and coined the term nanoantibodies (nAbs. Further studies in animal models and in humans will show how useful nAbs could be as therapeutics and diagnostics.

  17. Multiple functional roles of the accessory I-domain of bacteriophage P22 coat protein revealed by NMR structure and CryoEM modeling.

    Science.gov (United States)

    Rizzo, Alessandro A; Suhanovsky, Margaret M; Baker, Matthew L; Fraser, LaTasha C R; Jones, Lisa M; Rempel, Don L; Gross, Michael L; Chiu, Wah; Alexandrescu, Andrei T; Teschke, Carolyn M

    2014-06-10

    Some capsid proteins built on the ubiquitous HK97-fold have accessory domains imparting specific functions. Bacteriophage P22 coat protein has a unique insertion domain (I-domain). Two prior I-domain models from subnanometer cryoelectron microscopy (cryoEM) reconstructions differed substantially. Therefore, the I-domain's nuclear magnetic resonance structure was determined and also used to improve cryoEM models of coat protein. The I-domain has an antiparallel six-stranded β-barrel fold, not previously observed in HK97-fold accessory domains. The D-loop, which is dynamic in the isolated I-domain and intact monomeric coat protein, forms stabilizing salt bridges between adjacent capsomers in procapsids. The S-loop is important for capsid size determination, likely through intrasubunit interactions. Ten of 18 coat protein temperature-sensitive-folding substitutions are in the I-domain, indicating its importance in folding and stability. Several are found on a positively charged face of the β-barrel that anchors the I-domain to a negatively charged surface of the coat protein HK97-core. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. The Power of Poincar\\'e: Elucidating the Hidden Symmetries in Focal Conic Domains

    OpenAIRE

    Alexander, Gareth P.; Chen, Bryan Gin-ge; Matsumoto, Elisabetta A.; Kamien, Randall D.

    2010-01-01

    Focal conic domains are typically the "smoking gun" by which smectic liquid crystalline phases are identified. The geometry of the equally-spaced smectic layers is highly generic but, at the same time, difficult to work with. In this Letter we develop an approach to the study of focal sets in smectics which exploits a hidden Poincar\\'e symmetry revealed only by viewing the smectic layers as projections from one-higher dimension. We use this perspective to shed light upon several classic focal...

  19. Domain decomposition method for solving elliptic problems in unbounded domains

    International Nuclear Information System (INIS)

    Khoromskij, B.N.; Mazurkevich, G.E.; Zhidkov, E.P.

    1991-01-01

    Computational aspects of the box domain decomposition (DD) method for solving boundary value problems in an unbounded domain are discussed. A new variant of the DD-method for elliptic problems in unbounded domains is suggested. It is based on the partitioning of an unbounded domain adapted to the given asymptotic decay of an unknown function at infinity. The comparison of computational expenditures is given for boundary integral method and the suggested DD-algorithm. 29 refs.; 2 figs.; 2 tabs

  20. Isolation and molecular identification of planctomycete bacteria from postlarvae of the giant tiger prawn, Penaeus monodon.

    Science.gov (United States)

    Fuerst, J A; Gwilliam, H G; Lindsay, M; Lichanska, A; Belcher, C; Vickers, J E; Hugenholtz, P

    1997-01-01

    Bacteria phenotypically resembling members of the phylogenetically distinct planctomycete group of the domain Bacteria were isolated from postlarvae of the giant tiger prawn, Penaeus monodon. A selective medium designed in the light of planctomycete antibiotic resistance characteristics was used for this isolation. Planctomycetes were isolated from both healthy and monodon baculovirus-infected prawn postlarvae. The predominant colony type recovered from postlarvae regardless of viral infection status was nonpigmented. Other, less commonly observed types were pink or orange pigmented. A planctomycete-specific 16S rRNA-directed probe was designed and used to screen the isolates for their identity as planctomycetes prior to molecular phylogenetic characterization. 16S rRNA genes from nine prawn isolates together with two planctomycete reference strains (Planctomyces brasiliensis and Gemmata obscuriglobus) were sequenced and compared with reference sequences from the planctomycetes and other members of the domain Bacteria. Phylogenetic analyses and sequence signatures of the 16S rRNA genes demonstrated that the prawn isolates were members of the planctomycete group. Five representatives of the predominant nonpigmented colony type were members of the Pirellula group within the planctomycetes, as were three pink-pigmented colony type representatives. Homology values and tree topology indicated that representatives of the nonpigmented and pink-pigmented colony types formed two discrete clusters within the Pirellula group, not identical to any known Pirellula species. A sole representative of the orange colony type was a member of the Planctomyces group, virtually identical in 16S rDNA sequence to P. brasiliensis, and exhibited distinctive morphology. PMID:8979353

  1. The isolation, characterization and evaluation of Frankia strains

    Energy Technology Data Exchange (ETDEWEB)

    Normand, P.; Lalonde, M.; Fortin, J.A.; Chatarpaul, L.

    1984-01-01

    Osmium tetroxide (OsO/sub 4/) was used as the sterilizing agent to isolate the nitrogen-fixing endophyte Frankia from nodules of host plants. This treatment resulted in a pure culture collection of 250 Frankia isolates from several species of Alnus (crispa, rugosa, viridis, glutinosa, and serrulata) and from other actinorhizal species from Quebec. Frankia isolates from A. viridis and S. canadensis are reported in this document for the first time. Sugars from whole-cell hydrolysates of the organisms were analysed by gas liquid chromatography to identify strains previously screened on the basis of morphology and infectivity. This technique proved especially useful for those isolates whose morphology was atypical (ACN8, ArgN22, SCN9, and SCN10). It was demonstrated that sugar analysis (2-O-methy-D-mannose, in particular) can be important in resolving the taxonomy of Frankia. The nitrogen-fixing efficiency of some Frankia strains was evaluated by inoculating A. crispa. It was found that the efficiency of organisms was not influenced by the host from which they were first isolated. However, significant differences between some isolates of the same provenance occurred. It was also found that those strains of Frankia which do not sporulate were more effective in fixing nitrogen than those which do. It is proposed that the terms type P and type N be used to designate spore positive (Sp/sup +/) and spore negative (Sp/sup -/) Frankia strains, respectively. Further, it is recommended that sporulation type be used as a valid basis for species definition in the genus Frankia. 118 refs., 16 figs., 10 tabs.

  2. A LigA three-domain region protects hamsters from lethal infection by Leptospira interrogans.

    Directory of Open Access Journals (Sweden)

    Mariana L Coutinho

    2011-12-01

    Full Text Available The leptospiral LigA protein consists of 13 bacterial immunoglobulin-like (Big domains and is the only purified recombinant subunit vaccine that has been demonstrated to protect against lethal challenge by a clinical isolate of Leptospira interrogans in the hamster model of leptospirosis. We determined the minimum number and location of LigA domains required for immunoprotection. Immunization with domains 11 and 12 was found to be required but insufficient for protection. Inclusion of a third domain, either 10 or 13, was required for 100% survival after intraperitoneal challenge with Leptospira interrogans serovar Copenhageni strain Fiocruz L1-130. As in previous studies, survivors had renal colonization; here, we quantitated the leptospiral burden by qPCR to be 1.2×10(3 to 8×10(5 copies of leptospiral DNA per microgram of kidney DNA. Although renal histopathology in survivors revealed tubulointerstitial changes indicating an inflammatory response to the infection, blood chemistry analysis indicated that renal function was normal. These studies define the Big domains of LigA that account for its vaccine efficacy and highlight the need for additional strategies to achieve sterilizing immunity to protect the mammalian host from leptospiral infection and its consequences.

  3. Semi-synthesis of a HGF/SF kringle one (K1) domain scaffold generates a potent in vivo MET receptor agonist.

    Science.gov (United States)

    Simonneau, Claire; Bérénice Leclercq; Mougel, Alexandra; Adriaenssens, Eric; Paquet, Charlotte; Raibaut, Laurent; Ollivier, Nathalie; Drobecq, Hervé; Marcoux, Julien; Cianférani, Sarah; Tulasne, David; de Jonge, Hugo; Melnyk, Oleg; Vicogne, Jérôme

    2015-03-01

    The development of MET receptor agonists is an important goal in regenerative medicine, but is limited by the complexity and incomplete understanding of its interaction with HGF/SF (Hepatocyte Growth Factor/Scatter Factor). NK1 is a natural occurring agonist comprising the N-terminal (N) and the first kringle (K1) domains of HGF/SF. In the presence of heparin, NK1 can self-associate into a "head to tail" dimer which is considered as the minimal structural module able to trigger MET dimerization and activation whereas isolated K1 and N domains showed a weak or a complete lack of agonistic activity respectively. Starting from these structural and biological observations, we investigated whether it was possible to recapitulate the biological properties of NK1 using a new molecular architecture of isolated N or K1 domains. Therefore, we engineered multivalent N or K1 scaffolds by combining synthetic and homogeneous site-specifically biotinylated N and K1 domains (NB and K1B) and streptavidin (S). NB alone or in complex failed to activate MET signaling and to trigger cellular phenotypes. Importantly and to the contrary of K1B alone, the semi-synthetic K1B/S complex mimicked NK1 MET agonist activity in cell scattering, morphogenesis and survival phenotypic assays. Impressively, K1B/S complex stimulated in vivo angiogenesis and, when injected in mice, protected the liver against fulminant hepatitis in a MET dependent manner whereas NK1 and HGF were substantially less potent. These data reveal that without N domain, proper multimerization of K1 domain is a promising strategy for the rational design of powerful MET agonists.

  4. Modeling Textural Processes during Self-Assembly of Plant-Based Chiral-Nematic Liquid Crystals

    Directory of Open Access Journals (Sweden)

    Yogesh K. Murugesan

    2010-12-01

    Full Text Available Biological liquid crystalline polymers are found in cellulosic, chitin, and DNA based natural materials. Chiral nematic liquid crystalline orientational order is observed frozen-in in the solid state in plant cell walls and is known as a liquid crystal analogue characterized by a helicoidal plywood architecture. The emergence of the plywood architecture by directed chiral nematic liquid crystalline self assembly has been postulated as the mechanism that leads to optimal cellulose fibril organization. In natural systems, tissue growth and development takes place in the presence of inclusions and secondary phases leaving behind characteristic defects and textures, which provide a unique testing ground for the validity of the liquid crystal self-assembly postulate. In this work, a mathematical model, based on the Landau-de Gennes theory of liquid crystals, is used to simulate defect textures arising in the domain of self assembly, due to presence of secondary phases representing plant cells, lumens and pit canals. It is shown that the obtained defect patterns observed in some plant cell walls are those expected from a truly liquid crystalline phase. The analysis reveals the nature and magnitude of the viscoelastic material parameters that lead to observed patterns in plant-based helicoids through directed self-assembly. In addition, the results provide new guidance to develop biomimetic plywoods for structural and functional applications.

  5. Ternary (liquid + liquid) equilibria of {trifluorotris(perfluoroethyl)phosphate based ionic liquids + thiophene + heptane}

    International Nuclear Information System (INIS)

    Marciniak, Andrzej; Królikowski, Marek

    2012-01-01

    Highlights: ► Ternary (liquid + liquid) equilibria for 3 ionic liquid + thiophene + heptane systems. ► The influence of ionic liquid structure on phase diagrams is discussed. ► High selectivity for separation of heptane/thiophene is observed. - Abstract: Ternary (liquid + liquid) equilibria for three systems containing ionic liquids {(4-(2-methoxyethyl)-4-methylmorpholinium trifluorotris(perfluoroethyl)phosphate, 1-(2-methoxyethyl)-1-methylpiperidinium trifluorotris(perfluoroethyl)phosphate, 1-(2-methoxyethyl)-1-methylpyrrolidinium trifluorotris(perfluoroethyl)phosphate) + thiophene + heptane} have been determined at T = 298.15 K. All systems showed high solubility of thiophene in the ionic liquid and low solubility of heptane. The solute distribution coefficient and the selectivity were calculated for all systems. High values of selectivity were obtained. The experimental results have been correlated using NRTL model. The influence of ionic liquid structure on phase equilibria is discussed.

  6. The SHOCT domain: a widespread domain under-represented in model organisms.

    Directory of Open Access Journals (Sweden)

    Ruth Y Eberhardt

    Full Text Available We have identified a new protein domain, which we have named the SHOCT domain (Short C-terminal domain. This domain is widespread in bacteria with over a thousand examples. But we found it is missing from the most commonly studied model organisms, despite being present in closely related species. It's predominantly C-terminal location, co-occurrence with numerous other domains and short size is reminiscent of the Gram-positive anchor motif, however it is present in a much wider range of species. We suggest several hypotheses about the function of SHOCT, including oligomerisation and nucleic acid binding. Our initial experiments do not support its role as an oligomerisation domain.

  7. Liquid-Liquid Extraction in Systems Containing Butanol and Ionic Liquids – A Review

    OpenAIRE

    Kubiczek Artur; Kamiński Władysław

    2017-01-01

    Room-temperature ionic liquids (RTILs) are a moderately new class of liquid substances that are characterized by a great variety of possible anion-cation combinations giving each of them different properties. For this reason, they have been termed as designer solvents and, as such, they are particularly promising for liquid-liquid extraction, which has been quite intensely studied over the last decade. This paper concentrates on the recent liquid-liquid extraction studies involving ionic liqu...

  8. Nanomagnetic domains of chromium deposited on vertically-aligned carbon nanotubes

    International Nuclear Information System (INIS)

    Wright, Andrew C.; Faulkner, Michael K.; Harris, Robert C.; Goddard, Alex; Abbott, Andrew P.

    2012-01-01

    The drive to create ever smaller magnetic memory devices has led to the development of new nanomagnetic domains on surfaces. This paper reports the development of nano-chromium magnetic domains obtained using electrodeposition on vertically aligned carbon nanofibers arrays. Attempts to achieve this using conventional aqueous solutions were unsuccessful even after thin nickel underlayers were applied. The use of a novel electrolyte, a deep eutectic solvent, made from choline chloride: chromium (III) chloride enabled highly conformal overcoatings of chromium on individual bare carbon nanotubes to be obtained. Very high aspect ratio metal microstructures could be obtained by this novel technology. Magnetic imaging of the coated nanoarrays showed there to be clear magnetic character to the coating when the thin coatings were applied but this disappeared when the deposits were thicker and more contiguous. - Highlights: ► Nanoscale chromium deposited from non-aqueous electrolyte shows magnetic behavior. ► Vertically aligned carbon nanotubes conformally coated with chromium metal. ► Ionic liquid electrolyte superior to chromic acid for plating high aspect ratio structures.

  9. Nanomagnetic domains of chromium deposited on vertically-aligned carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Wright, Andrew C., E-mail: a.wright@glyndwr.ac.uk [Advanced Materials Research Laboratory, Materials Science Research Center, Glyndwr University, Wrexham LL11 2AW (United Kingdom); Faulkner, Michael K., E-mail: m.faulkner@manchester.ac.uk [Manchester Materials Science Centre, University of Manchester, Grosvenor Street, Manchester M13 9PL (United Kingdom); Harris, Robert C.; Goddard, Alex; Abbott, Andrew P., E-mail: apa1@le.ac.uk [Department of Chemistry, University of Leicester, Leicester LE1 7RH (United Kingdom)

    2012-12-15

    The drive to create ever smaller magnetic memory devices has led to the development of new nanomagnetic domains on surfaces. This paper reports the development of nano-chromium magnetic domains obtained using electrodeposition on vertically aligned carbon nanofibers arrays. Attempts to achieve this using conventional aqueous solutions were unsuccessful even after thin nickel underlayers were applied. The use of a novel electrolyte, a deep eutectic solvent, made from choline chloride: chromium (III) chloride enabled highly conformal overcoatings of chromium on individual bare carbon nanotubes to be obtained. Very high aspect ratio metal microstructures could be obtained by this novel technology. Magnetic imaging of the coated nanoarrays showed there to be clear magnetic character to the coating when the thin coatings were applied but this disappeared when the deposits were thicker and more contiguous. - Highlights: Black-Right-Pointing-Pointer Nanoscale chromium deposited from non-aqueous electrolyte shows magnetic behavior. Black-Right-Pointing-Pointer Vertically aligned carbon nanotubes conformally coated with chromium metal. Black-Right-Pointing-Pointer Ionic liquid electrolyte superior to chromic acid for plating high aspect ratio structures.

  10. Large scale phononic metamaterials for seismic isolation

    International Nuclear Information System (INIS)

    Aravantinos-Zafiris, N.; Sigalas, M. M.

    2015-01-01

    In this work, we numerically examine structures that could be characterized as large scale phononic metamaterials. These novel structures could have band gaps in the frequency spectrum of seismic waves when their dimensions are chosen appropriately, thus raising the belief that they could be serious candidates for seismic isolation structures. Different and easy to fabricate structures were examined made from construction materials such as concrete and steel. The well-known finite difference time domain method is used in our calculations in order to calculate the band structures of the proposed metamaterials

  11. Interaction of slow electrons with high-pressure gases ('Quasi-liquids'): synthesis of our knowledge on slow electron-molecule interactions. Progress report

    International Nuclear Information System (INIS)

    McCorkle, D.L.; Christophorou, L.G.

    1985-01-01

    A crucial step in our efforts to develop not only a coherent picture of radiation interaction with matter, but also to understand radiation effects and mechanisms, as well as the effects of chemical pollutants and toxic compounds, is to relate the often abundant knowledge on isolated molecules (low pressure gases) to that on liquids or solids. To understand the roles of the physical and chemical properties of molecules in biological reactions, we must know how these isolated-molecule properties change as molecules are embedded in gradually thicker and thicker (denser and denser) gaseous and, finally, liquid environments. The work initiated by us both at the Physics Department of The University of Tennessee and at the Oak Ridge National Laboratory addresses itself to this question. At both places, high pressure (40 to approx.8000 kPa) electron swarm experiments are currently in operation yielding information as to the effects of the density and nature of the environment on fundamental electron-molecule interaction processes at densities intermediate to those corresponding to low pressure gases and liquids, and the gradual transition from isolated molecule to condensed phase behavior

  12. Domain-to-domain coupling in voltage-sensing phosphatase.

    Science.gov (United States)

    Sakata, Souhei; Matsuda, Makoto; Kawanabe, Akira; Okamura, Yasushi

    2017-01-01

    Voltage-sensing phosphatase (VSP) consists of a transmembrane voltage sensor and a cytoplasmic enzyme region. The enzyme region contains the phosphatase and C2 domains, is structurally similar to the tumor suppressor phosphatase PTEN, and catalyzes the dephosphorylation of phosphoinositides. The transmembrane voltage sensor is connected to the phosphatase through a short linker region, and phosphatase activity is induced upon membrane depolarization. Although the detailed molecular characteristics of the voltage sensor domain and the enzyme region have been revealed, little is known how these two regions are coupled. In addition, it is important to know whether mechanism for coupling between the voltage sensor domain and downstream effector function is shared among other voltage sensor domain-containing proteins. Recent studies in which specific amino acid sites were genetically labeled using a fluorescent unnatural amino acid have enabled detection of the local structural changes in the cytoplasmic region of Ciona intestinalis VSP that occur with a change in membrane potential. The results of those studies provide novel insight into how the enzyme activity of the cytoplasmic region of VSP is regulated by the voltage sensor domain.

  13. A GENERIC PACKAGING TECHNIQUE USING FLUIDIC ISOLATION FOR LOW-DRIFT IMPLANTABLE PRESSURE SENSORS.

    Science.gov (United States)

    Kim, A; Powell, C R; Ziaie, B

    2015-06-01

    This paper reports on a generic packaging method for reducing drift in implantable pressure sensors. The described technique uses fluidic isolation by encasing the pressure sensor in a liquid-filled medical-grade polyurethane balloon; thus, isolating it from surrounding aqueous environment that is the major source of baseline drift. In-vitro tests using commercial micromachined piezoresistive pressure sensors show an average baseline drift of 0.006 cmH 2 O/day (0.13 mmHg/month) for over 100 days of saline soak test, as compared to 0.101 cmH 2 O/day (2.23 mmHg/month) for a non-fluidic-isolated one soaked for 18 days. To our knowledge, this is the lowest reported drift for an implantable pressure sensor.

  14. Isolation and life cycle characterization of lytic viruses infecting heterotrophic bacteria and cyanobacteria

    DEFF Research Database (Denmark)

    Middelboe, Mathias; Chan, Amy; Bertelsen, Sif Koldborg

    2010-01-01

    Basic knowledge on viruses infecting heterotrophic bacteria and cyanobacteria is key to future progress in understanding the role of viruses in aquatic systems and the influence of virus–host interactions on microbial mortality, biogeochemical cycles, and genetic exchange. Such studies require......, and discusses the applications and limitations of different isolation procedures. Most work on phage isolation has been carried out with aerobic heterotrophic bacteria and cyanobacteria, culturable both on agar plates and in enriched liquid cultures. The procedures presented here are limited to lytic viruses...... infecting such hosts. In addition to the isolation procedures, methods for life cycle characterization (one-step growth experiments) of bacteriophages and cyanophages are described. Finally, limitations and drawbacks of the proposed methods are assessed and discussed...

  15. Structural mechanism of voltage-dependent gating in an isolated voltage-sensing domain.

    Science.gov (United States)

    Li, Qufei; Wanderling, Sherry; Paduch, Marcin; Medovoy, David; Singharoy, Abhishek; McGreevy, Ryan; Villalba-Galea, Carlos A; Hulse, Raymond E; Roux, Benoît; Schulten, Klaus; Kossiakoff, Anthony; Perozo, Eduardo

    2014-03-01

    The transduction of transmembrane electric fields into protein motion has an essential role in the generation and propagation of cellular signals. Voltage-sensing domains (VSDs) carry out these functions through reorientations of positive charges in the S4 helix. Here, we determined crystal structures of the Ciona intestinalis VSD (Ci-VSD) in putatively active and resting conformations. S4 undergoes an ~5-Å displacement along its main axis, accompanied by an ~60° rotation. This movement is stabilized by an exchange in countercharge partners in helices S1 and S3 that generates an estimated net charge transfer of ~1 eo. Gating charges move relative to a ''hydrophobic gasket' that electrically divides intra- and extracellular compartments. EPR spectroscopy confirms the limited nature of S4 movement in a membrane environment. These results provide an explicit mechanism for voltage sensing and set the basis for electromechanical coupling in voltage-dependent enzymes and ion channels.

  16. Structure of the C-type lectin carbohydrate recognition domain of human Tetranectin

    DEFF Research Database (Denmark)

    Kastrup, Jette Sandholm Jensen; Nielsen, Bettina Bryde; Rasmussen, Hanne B.

    1998-01-01

    Tetranectin (TN) is a C-type lectin involved in fibrinolysis, being the only endogenous ligand known to bind specifically to the kringle 4 domain of plasminogen. TN was originally isolated from plasma, but shows a wide tissue distribution. Furthermore, TN has been found in the extracellular matri...... molecules. One sulfate ion has been located at the surface of TN3, forming contacts to Glu120, Lys148, Asn106 of a symmetry-related molecule, and to an ethanol molecule....

  17. Domain wall propagation tuning in magnetic nanowires through geometric modulation

    Energy Technology Data Exchange (ETDEWEB)

    Arzuza, L.C.C., E-mail: luisarzuza179@gmail.com [Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, 13083-859 Campinas (SP) (Brazil); Universidad de la Costa, Departamento de Ciencias Naturales y Exactas, Calle 58 No. 55-66, Barranquilla (Colombia); López-Ruiz, R. [Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, 13083-859 Campinas (SP) (Brazil); Salazar-Aravena, D. [Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, 13083-859 Campinas (SP) (Brazil); Departamento de Física, Facultad de Ciencias, Universidad de Tarapacá, 1000007 Arica (Chile); Knobel, M. [Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, 13083-859 Campinas (SP) (Brazil); Brazilian Nanotechnology National Laboratory, Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), 13083-970 Campinas (SP) (Brazil); Béron, F.; Pirota, K.R. [Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, 13083-859 Campinas (SP) (Brazil)

    2017-06-15

    Highlights: • The modulated nanowires dynamics occurs through two reversal modes. • Modulated nanowires show a change in the χ in contrast to homogeneous ones. • The FORC method reveals a non-uniform stray field due to shape modulation. - Abstract: The magnetic behavior of nickel modulated nanowires embedded in porous alumina membranes is investigated. Their diameters exhibit a sharp transition between below (35 nm) and above (52 nm) the theoretical limit for transverse and vortex domain walls. Magnetic hysteresis loops and first-order reversal curves (FORCs) were measured on several ordered nanowire arrays with different wide-narrow segment lengths ratio and compared with those from homogenous nanowires. The experimental magnetic response evidences a rather complex susceptibility behavior for nanowires with modulated diameter. Micromagnetic simulations on isolated and first-neighbors arrays of nanowires show that the domain wall structure, which depends on the segment diameter, suffers a transformation while crossing the diameter modulation, but without any pinning. The experimental array magnetic behavior can be ascribed to a heterogeneous stray field induced by the diameter modulation, yielding a stronger interaction field at the wide extremity than at the narrow one. The results evidence the possibility to control the domain wall propagation and morphology by modulating the lateral aspect of the magnetic entity.

  18. Chemical and colour quenching in liquid scintillation counting

    International Nuclear Information System (INIS)

    Grau Malonda, A.; Scott Guilleard, P.E.

    1986-01-01

    Chemical and colour quenching for H-3 and C-14 was studied. The method includes spectral analysis of colouring agents; methyl red (4'-dimethylamine-azobenzene 2-carboxilic acid) dimethyl yellow (4'-dimethylamine-azobenzene) and melachite green (metane, bis (4'-dimethyl aminophenyl)-(phenyl)). External standard channels ratio was applied for the liquid scintillation counting of samples. The introduction of an isolated external standard seems to be a strong tool for the correction of chemical and colour quenching curves. (author). 10 figs., 12 refs

  19. Chemical and colour quenching in liquid scintillation counting

    International Nuclear Information System (INIS)

    Scott G, P. E.; Grau M, A.

    1987-01-01

    Chemical and colour quenching for H-3 and C-14 was studied. The method includes spectral analysis of colouring agents; methyl red, (4'-dimethylamine-azobenzene 2-carboxylic acid) dimethyl yellow (4'-dimethylamine-azobenzene) and malachite green (methane, bis .(4-dimethyl aminophenyl) - (phenyl)). External standard channels ratio was applied for the liquid scintillation counting of samples. The introduction of an isolated external standard seems to be a strong tool for the correction of chemical and colour quenching curves. (Author) 12 refs

  20. MIT domain of Vps4 is a Ca2+-dependent phosphoinositide-binding domain.

    Science.gov (United States)

    Iwaya, Naoko; Takasu, Hirotoshi; Goda, Natsuko; Shirakawa, Masahiro; Tanaka, Toshiki; Hamada, Daizo; Hiroaki, Hidekazu

    2013-05-01

    The microtubule interacting and trafficking (MIT) domain is a small protein module that is conserved in proteins of diverged function, such as Vps4, spastin and sorting nexin 15 (SNX15). The molecular function of the MIT domain is protein-protein interaction, in which the domain recognizes peptides containing MIT-interacting motifs. Recently, we identified an evolutionarily related domain, 'variant' MIT domain at the N-terminal region of the microtubule severing enzyme katanin p60. We found that the domain was responsible for binding to microtubules and Ca(2+). Here, we have examined whether the authentic MIT domains also bind Ca(2+). We found that the loop between the first and second α-helices of the MIT domain binds a Ca(2+) ion. Furthermore, the MIT domains derived from Vps4b and SNX15a showed phosphoinositide-binding activities in a Ca(2+)-dependent manner. We propose that the MIT domain is a novel membrane-associating domain involved in endosomal trafficking.

  1. The PH domain of phosphoinositide-dependent kinase-1 exhibits a novel, phospho-regulated monomer-dimer equilibrium with important implications for kinase domain activation: single-molecule and ensemble studies.

    Science.gov (United States)

    Ziemba, Brian P; Pilling, Carissa; Calleja, Véronique; Larijani, Banafshé; Falke, Joseph J

    2013-07-16

    Phosphoinositide-dependent kinase-1 (PDK1) is an essential master kinase recruited to the plasma membrane by the binding of its C-terminal PH domain to the signaling lipid phosphatidylinositol-3,4,5-trisphosphate (PIP3). Membrane binding leads to PDK1 phospho-activation, but despite the central role of PDK1 in signaling and cancer biology, this activation mechanism remains poorly understood. PDK1 has been shown to exist as a dimer in cells, and one crystal structure of its isolated PH domain exhibits a putative dimer interface. It has been proposed that phosphorylation of PH domain residue T513 (or the phospho-mimetic T513E mutation) may regulate a novel PH domain dimer-monomer equilibrium, thereby converting an inactive PDK1 dimer to an active monomer. However, the oligomeric states of the PH domain on the membrane have not yet been determined, nor whether a negative charge at position 513 is sufficient to regulate its oligomeric state. This study investigates the binding of purified wild-type (WT) and T513E PDK1 PH domains to lipid bilayers containing the PIP3 target lipid, using both single-molecule and ensemble measurements. Single-molecule analysis of the brightness of the fluorescent PH domain shows that the PIP3-bound WT PH domain on membranes is predominantly dimeric while the PIP3-bound T513E PH domain is monomeric, demonstrating that negative charge at the T513 position is sufficient to dissociate the PH domain dimer and is thus likely to play a central role in PDK1 monomerization and activation. Single-molecule analysis of two-dimensional (2D) diffusion of PH domain-PIP3 complexes reveals that the dimeric WT PH domain diffuses at the same rate as a single lipid molecule, indicating that only one of its two PIP3 binding sites is occupied and there is little penetration of the protein into the bilayer as observed for other PH domains. The 2D diffusion of T513E PH domain is slower, suggesting the negative charge disrupts local structure in a way that allows

  2. Detection of radiation-induced hydrocarbons in baked sponged cake prepared with irradiated liquid egg

    Science.gov (United States)

    Schulzki, G.; Spiegelberg, A.; Bögl, K. W.; Schreiber, G. A.

    1995-02-01

    For identification of irradiated food, radiation-induced volatile hydrocarbons (HC) are determined by gas chromatography in the non-polar fraction of fat. However, in complex food matrices the detection is often disturbed by fat-associated compounds. On-line coupling of high performance liquid chromatography (LC) and gas chromatography (GC) is very efficient to remove such compounds from the HC fraction. The high sensitivity of this fast and efficient technique is demonstrated by the example of detection of radiation-induced HC in fat isolated from baked sponge cake which had been prepared with irradiated liquid egg.

  3. Dewetting of thin liquid films on chemically patterned substrates : front propatation along narrow lyophobic stripes and stripe arrays

    NARCIS (Netherlands)

    Brasjen, B.J.; Gu, H.; Darhuber, A.A.

    2013-01-01

    Using experiments and numerical simulations, we investigate the dewetting of thin liquid films on chemically patterned substrates. The patterns consist of long and narrow hydrophobic stripes, separated by larger hydrophilic domains. We characterize the morphology and dynamics of the dewetting front

  4. Cooling device upon reactor isolation

    International Nuclear Information System (INIS)

    Otsu, Tatsuya

    1995-01-01

    A vacuum breaking valve is disposed to a sucking pipeline of vacuum pumps. A sucking port of the breaking valve is connected with an exhaustion side of a relief valve of a liquid nitrogen-filled tank by way of communication pipes. When a cooling device is operated upon reactor isolation and the vacuum pumps are operated, a three directional electromagnetic valve is operated, and nitrogen discharged out of the exhaustion port of the relief valve of the liquid nitrogen-filled tank is sent to a nitrogen releasing port on the suction side of the vacuum breaking valve by way of the communication pipes and released to atmosphere. When the pressure in the vacuum tank is excessively lowered in this state and the vacuum breaking valve is opened, nitrogen flows from the nitrogen discharge port into the vacuum tank through the breaking valve, and are sent to a pressure suppression chamber by the vacuum pumps. Since a great amount of nitrogen is sent to the pressure suppression chamber, and the inflow of the air is reduced, increase of oxygen concentration in the pressure suppression chamber can be suppressed. (I.N.)

  5. Rational and Efficient Preparative Isolation of Natural Products by MPLC-UV-ELSD based on HPLC to MPLC Gradient Transfer.

    Science.gov (United States)

    Challal, Soura; Queiroz, Emerson Ferreira; Debrus, Benjamin; Kloeti, Werner; Guillarme, Davy; Gupta, Mahabir Prashad; Wolfender, Jean-Luc

    2015-11-01

    In natural product research, the isolation of biomarkers or bioactive compounds from complex natural extracts represents an essential step for de novo identification and bioactivity assessment. When pure natural products have to be obtained in milligram quantities, the chromatographic steps are generally labourious and time-consuming. In this respect, an efficient method has been developed for the reversed-phase gradient transfer from high-performance liquid chromatography to medium-performance liquid chromatography for the isolation of pure natural products at the level of tens of milligrams from complex crude natural extracts. The proposed method provides a rational way to predict retention behaviour and resolution at the analytical scale prior to medium-performance liquid chromatography, and guarantees similar performances at both analytical and preparative scales. The optimisation of the high-performance liquid chromatography separation and system characterisation allows for the prediction of the gradient at the medium-performance liquid chromatography scale by using identical stationary phase chemistries. The samples were introduced in medium-performance liquid chromatography using a pressure-resistant aluminium dry load cell especially designed for this study to allow high sample loading while maintaining a maximum achievable flow rate for the separation. The method has been validated with a mixture of eight natural product standards. Ultraviolet and evaporative light scattering detections were used in parallel for a comprehensive monitoring. In addition, post-chromatographic mass spectrometry detection was provided by high-throughput ultrahigh-performance liquid chromatography time-of-flight mass spectrometry analyses of all fractions. The processing of all liquid chromatography-mass spectrometry data in the form of an medium-performance liquid chromatography x ultra high-performance liquid chromatography time-of-flight mass spectrometry matrix enabled an

  6. Structure and lifetimes in ionic liquids and their mixtures.

    Science.gov (United States)

    Gehrke, Sascha; von Domaros, Michael; Clark, Ryan; Hollóczki, Oldamur; Brehm, Martin; Welton, Tom; Luzar, Alenka; Kirchner, Barbara

    2018-01-01

    With the aid of molecular dynamics simulations, we study the structure and dynamics of different ionic liquid systems, with focus on hydrogen bond, ion pair and ion cage formation. To do so, we report radial distribution functions, their number integrals, and various time-correlation functions, from which we extract well-defined lifetimes by means of the reactive flux formalism. We explore the influence of polarizable force fields vs. non-polarizable ones with downscaled charges (±0.8) for the example of 1-butyl-3-methylimidazolium bromide. Furthermore, we use 1-butyl-3-methylimidazolium trifluoromethanesulfonate to investigate the impact of temperature and mixing with water as well as with the chloride ionic liquid. Smaller coordination numbers, larger distances, and tremendously accelerated dynamics are observed when the polarizable force field is applied. The same trends are found with increasing temperature. Adding water decreases the ion-ion coordination numbers whereas the water-ion and water-water coordination is enhanced. A domain analysis reveals that the nonpolar parts of the ions are dispersed and when more water is added the water clusters increase in size. The dynamics accelerate in general upon addition of water. In the ionic liquid mixture, the coordination number around the cation changes between the two anions, but the number integrals of the cation around the anions remain constant and the dynamics slow down with increasing content of the chloride ionic liquid.

  7. The isolation and the separation of Sm, Gd, Dy by extraction

    International Nuclear Information System (INIS)

    Biyantoro, D.; Lahagu, F.; Basuki, K.T.; Handini, T.; Rosyidin

    1996-01-01

    The isolation of yttrium and separation of Sm, Gd, y with extraction has been investigated. The steps of the process include of this research were the production the concentrate of lanthanide, the dilution, the isolation of yttrium, and the separation of the Sm, Gd, Dy. The first step was the digestion of xenotime sand, the extraction, the dilution, the filtration, the precipitation, the baking production a lanthanide oxide. The step was the separation of yttrium, the stripping, and the calcination production of yttrium oxide. And the third process was the separation of Sm, Gd, Dy by extraction process using method liquid-liquid extraction with extractant of D 2 EHPA and a solvent of dodecane. From the result have been found concentration of yttrium oxide = 88,71 %. The optimum condition of the separation of Gd/Dy have been found : the concentration of HNO 3 = 0,5 M, time of extraction = 15 minutes, and the concentration of extractant = 30 % D 2 EHPA in dodecane. The results of this condition were the distribution coefficient of Gd = 2,226, the distribution coefficient of Dy = 3,762, and the separation factor of Gd/Dy = 0,592. (author)

  8. A Simple Procedure to Evaluate Competitiveness of Toxigenic and Atoxigenic Isolates of Aspergillus flavus in Solid and Liquid Media

    Directory of Open Access Journals (Sweden)

    Mohammad Moradi

    2017-04-01

    Full Text Available Application of atoxigenic strains of Aspergillus flavus to reduce aflatoxin levels is the most successful strategy applied in some agricultural crops. The role of ammonium hydroxide for preliminary screening of the competitiveness of atoxigenic A. flavus isolates to interfere with aflatoxin production by highly toxigenic isolates were evaluated. Out of 270 A. flavus isolates, 17 were detected as true atoxigenic using cultural methods and confirmed by analytical assays from different pistachio agro-ecological zones during 2013. For assessment competitive ability among atoxigenic isolates of A. flavus with highly toxigenic one, rice flour, coconut agar and coconut broth medium substrates were inoculated with mixtures including combinations of toxigenic and atoxigenic isolates, simultaneously. The rice flour substrate was used to quantify the content of aflatoxin in either co-inoculations or toxigenic isolate alone on thin layer chromatography plates with a scanning densitometer. While the culture media were used to determine the intensity of color change on exposing to ammonium hydroxide vapor. The reduction rates of aflatoxin B1 in co-inoculations were varied and ranged from 2%-82%. Based on the intensity of colony color changes, the competitiveness of the isolates was classified into five groups. Atoxigenic isolates with high competitiveness have shown low color changes in culture media and high aflatoxin reduction in TLC assays with a ratio of higher than 78%. The method will facilitate preliminary screening of efficient atoxigenic isolates for mitigation of aflatoxins in food and feed as a cheap, simple and quick method.

  9. Isolation of Asphaltene-Degrading Bacteria from Sludge Oil

    Directory of Open Access Journals (Sweden)

    Pingkan Aditiawati

    2015-03-01

    Full Text Available Sludge oil contains 30%–50% hydrocarbon fractions that comprise saturated fractions, aromatics, resins, and asphaltene. Asphaltene fraction is the most persistent fraction. In this research, the indigenous bacteria that can degrade asphaltene fractions from a sludge oil sample from Balikpapan that was isolated using BHMS medium (Bushnell-Hass Mineral Salt with 0.01% (w/v yeast extract, 2% (w/v asphaltene extract, and 2% (w/v sludge oil. The ability of the four isolates to degrade asphaltene fractions was conducted by the biodegradation asphaltene fractions test using liquid cultures in a BHMS medium with 0.01% (w/v yeast extract and 2% (w/v asphaltene extract as a carbon source. The parameters measured during the process of biodegradation of asphaltene fractions include the quantification of Total Petroleum Hydrocarbon (g, log total number of bacteria (CFU/ml, and pH. There are four bacteria (isolates 1, 2, 3, and 4 that have been characterized to degrade asphaltic fraction and have been identified as Bacillus sp. Lysinibacillus fusiformes, Acinetobacter sp., and Mycobacterium sp., respectively. The results showed that the highest ability to degrade asphaltene fractions is that of Bacillus sp. (isolate 1 and Lysinibacillus fusiformes (Isolate 2, with biodegradation percentages of asphaltene fractions being 50% and 55%, respectively, and growth rate at the exponential phase is 7.17x107 CFU/mL.days and 4.21x107 CFU/mL.days, respectively.

  10. Magnetic domains and frustration in metallic CePdAl

    Energy Technology Data Exchange (ETDEWEB)

    Lucas, Stefan; Huesges, Zita; Huang, Chien-Lung; Stockert, Oliver [Max Planck Institute CPfS, Dresden (Germany); Fritsch, Veronika; Sakai, Akito [EP 6, Electronic Correlations and Magnetism, University of Augsburg (Germany); Grube, Kai; Taubenheim, Christian; Loehneysen, Hilbert von [Karlsruhe Institute of Technology (Germany)

    2016-07-01

    Magnetic frustration is an exciting topic in condensed matter physics, since it can lead to new ground states of materials, e.g. a spin liquid or spin glass state. Effects of magnetic frustration have been investigated intensively for insulating materials. However, the existence of magnetic frustration in metallic systems is still under debate. CePdAl is a metallic Kondo system, where geometric magnetic frustration arises from the formation of Ce ions on a distorted Kagome lattice. Neutron scattering experiments revealed, that only two thirds of the magnetic Ce moments order antiferromagnetically below T{sub N}=2.7 K, whereas the other third remains mainly disordered. Thermodynamic as well as neutron scattering measurements are presented to verify the existence of partial magnetic frustration in CePdAl. Recently neutron diffraction experiments under magnetic fields applied along two orthogonal directions in the magnetically hard basal plane were performed. They show opposite effects on the magnetic intensity of a selected magnetic domain depending on the field direction with respect to the propagation vector. If this is only an effect of different domain population or also due to a change in magnetic frustration shall be discussed.

  11. Biodegradation of imidacloprid in liquid media by an isolated wastewater fungus Aspergillus terreus YESM3.

    Science.gov (United States)

    Mohammed, Youssef M M; Badawy, Mohammed E I

    2017-10-03

    In the present study, a new fungal strain capable of imidacloprid degradation was isolated from agricultural wastewater drain. The fungal strain of YESM3 was identified as Aspergillus terreus based on ITS1-5.8S rDNA-ITS2 gene sequence by PCR amplification of a 500 bp sequence. Screening of A. terreus YESM3 to the insecticide imidacloprid tolerance was achieved by growing fungus in Czapek Dox agar for 6 days at 28°C. High values (1.13 and 0.94 cm cm -1 ) of tolerance index (TI) were recorded at 25 and 50 mg L -1 of imidacloprid, respectively in the presence and absence of sucrose. However, at 400 mg L -1 the fungus did not grow. Effects of the imidacloprid concentration, pH, and inoculum size on the biodegradation percentage were tested using Box-Behnken statistical design and the biodegradation was monitored by HPLC analysis at different time intervals. Box-Behnken results indicated that optimal conditions for biodegradation were at pH 4 and two fungal discs (10 mm diameter) in the presence of 61.2 mg L -1 of imidacloprid. A. terreus YESM3 strain was capable of degrading 85% of imidacloprid 25 mg L -1 in Czapek Dox broth medium at pH 4 and 28°C for 6 days under static conditions. In addition, after 20 days of inoculation, biodegradation recorded 96.23% of 25 mg L -1 imidacloprid. Degradation kinetics showed that the imidacloprid followed the first order kinetics with half-life (t 50 ) of 1.532 day. Intermediate product identified as 6-chloronicotinic acid (6CNA) as one of the major metabolites during degradation of imidacloprid by using HPLC. Thus, A. terreus YESM3 showed a potential to reduce pollution by pesticides and toxicity in the effected environment. However, further studies should be conducted to understand the biodegradation mechanism of this pesticide in liquid media.

  12. Rhodotorula portillonensis sp. nov., a basidiomycetous yeast isolated from Antarctic shallow-water marine sediment.

    Science.gov (United States)

    Laich, Federico; Vaca, Inmaculada; Chávez, Renato

    2013-10-01

    During the characterization of the mycobiota associated with shallow-water marine environments from Antarctic sea, a novel pink yeast species was isolated. Sequence analysis of the D1/D2 domain of the LSU rDNA gene and 5.8S-ITS regions revealed that the isolated yeast was closely related to Rhodotorula pallida CBS 320(T) and Rhodotorula benthica CBS 9124(T). On the basis of morphological, biochemical and physiological characterization and phylogenetic analyses, a novel basidiomycetous yeast species, Rhodotorula portillonensis sp. nov., is proposed. The type strain is Pi2(T) ( = CBS 12733(T)  = CECT 13081(T)) which was isolated from shallow-water marine sediment in Fildes Bay, King George Island, Antarctica.

  13. Liquid-Liquid Extraction in Systems Containing Butanol and Ionic Liquids – A Review

    Directory of Open Access Journals (Sweden)

    Kubiczek Artur

    2017-03-01

    Full Text Available Room-temperature ionic liquids (RTILs are a moderately new class of liquid substances that are characterized by a great variety of possible anion-cation combinations giving each of them different properties. For this reason, they have been termed as designer solvents and, as such, they are particularly promising for liquid-liquid extraction, which has been quite intensely studied over the last decade. This paper concentrates on the recent liquid-liquid extraction studies involving ionic liquids, yet focusing strictly on the separation of n-butanol from model aqueous solutions. Such research is undertaken mainly with the intention of facilitating biological butanol production, which is usually carried out through the ABE fermentation process. So far, various sorts of RTILs have been tested for this purpose while mostly ternary liquid-liquid systems have been investigated. The industrial design of liquid-liquid extraction requires prior knowledge of the state of thermodynamic equilibrium and its relation to the process parameters. Such knowledge can be obtained by performing a series of extraction experiments and employing a certain mathematical model to approximate the equilibrium. There are at least a few models available but this paper concentrates primarily on the NRTL equation, which has proven to be one of the most accurate tools for correlating experimental equilibrium data. Thus, all the presented studies have been selected based on the accepted modeling method. The reader is also shown how the NRTL equation can be used to model liquid-liquid systems containing more than three components as it has been the authors’ recent area of expertise.

  14. Radiochemical aspects of liquid mercury spallation targets

    CERN Document Server

    Neuhausen, Joerg; Eichler, Bernd; Eller, Martin; Horn, Susanne; Schumann, Dorothea; Stora, Thierry

    2012-01-01

    Liquid metal spallation targets using mercury as target material are used in state-of-the-art high power pulsed neutron sources that have been constructed in the USA and Japan within the last decade. Similar target concepts were also proposed for next generation ISOL, beta-beam and neutrino facilities. A large amount of radioactivity will be induced in the liquid metal during operation caused by the interaction of the target material with the intense proton beam. This radioactivity - carried by a wide range of radioisotopes of all the elements of the periodic table from hydrogen up to thallium - must be considered for the assessment of safe operation and maintenance procedures as well as for a final disposal of the used target material and components. This report presents an overview on chemical investigations performed in our laboratory that deal with the behavior of radionuclides in proton irradiated mercury samples. The solubility of elements in mercury was calculated using thermodynamical data obtained by...

  15. Conversion of Dielectric Data from the Time Domain to the Frequency Domain

    Directory of Open Access Journals (Sweden)

    Vladimir Durman

    2005-01-01

    Full Text Available Polarisation and conduction processes in dielectric systems can be identified by the time domain or the frequency domain measurements. If the systems is a linear one, the results of the time domain measurements can be transformed into the frequency domain, and vice versa. Commonly, the time domain data of the absorption conductivity are transformed into the frequency domain data of the dielectric susceptibility. In practice, the relaxation are mainly evaluated by the frequency domain data. In the time domain, the absorption current measurement were prefered up to now. Recent methods are based on the recovery voltage measurements. In this paper a new method of the recovery data conversion from the time the frequency domain is proposed. The method is based on the analysis of the recovery voltage transient based on the Maxwell equation for the current density in a dielectric. Unlike the previous published solutions, the Laplace fransform was used to derive a formula suitable for practical purposes. the proposed procedure allows also calculating of the insulation resistance and separating the polarisation and conduction losses.

  16. Predicting detection performance with model observers: Fourier domain or spatial domain?

    Science.gov (United States)

    Chen, Baiyu; Yu, Lifeng; Leng, Shuai; Kofler, James; Favazza, Christopher; Vrieze, Thomas; McCollough, Cynthia

    2016-02-27

    The use of Fourier domain model observer is challenged by iterative reconstruction (IR), because IR algorithms are nonlinear and IR images have noise texture different from that of FBP. A modified Fourier domain model observer, which incorporates nonlinear noise and resolution properties, has been proposed for IR and needs to be validated with human detection performance. On the other hand, the spatial domain model observer is theoretically applicable to IR, but more computationally intensive than the Fourier domain method. The purpose of this study is to compare the modified Fourier domain model observer to the spatial domain model observer with both FBP and IR images, using human detection performance as the gold standard. A phantom with inserts of various low contrast levels and sizes was repeatedly scanned 100 times on a third-generation, dual-source CT scanner at 5 dose levels and reconstructed using FBP and IR algorithms. The human detection performance of the inserts was measured via a 2-alternative-forced-choice (2AFC) test. In addition, two model observer performances were calculated, including a Fourier domain non-prewhitening model observer and a spatial domain channelized Hotelling observer. The performance of these two mode observers was compared in terms of how well they correlated with human observer performance. Our results demonstrated that the spatial domain model observer correlated well with human observers across various dose levels, object contrast levels, and object sizes. The Fourier domain observer correlated well with human observers using FBP images, but overestimated the detection performance using IR images.

  17. Nucleic acid sequences encoding D1 and D1/D2 domains of human coxsackievirus and adenovirus receptor (CAR)

    Science.gov (United States)

    Freimuth, Paul I.

    2010-04-06

    The invention provides recombinant human CAR (coxsackievirus and adenovirus receptor) polypeptides which bind adenovirus. Specifically, polypeptides corresponding to adenovirus binding domain D1 and the entire extracellular domain of human CAR protein comprising D1 and D2 are provided. In another aspect, the invention provides nucleic acid sequences encoding these domains and expression vectors for producing the domains and bacterial cells containing such vectors. The invention also includes an isolated fusion protein comprised of the D1 polypeptide fused to a polypeptide which facilitates folding of D1 when expressed in bacteria. The functional D1 domain finds application in a therapeutic method for treating a patient infected with a CAR D1-binding virus, and also in a method for identifying an antiviral compound which interferes with viral attachment. The invention also provides a method for specifically targeting a cell for infection by a virus which binds to D1.

  18. Isolated velopalatine paralysis associated with parvovirus B19 infection

    Directory of Open Access Journals (Sweden)

    Soares-Fernandes João P.

    2006-01-01

    Full Text Available A case of isolated velopalatine paralysis in an 8-year-old boy is presented. The symptoms were sudden-onset of nasal speech, regurgitation of liquids into the nose and dysphagia. Brain MRI and cerebrospinal fluid examination were normal. Infectious serologies disclosed an antibody arrangement towards parvovirus B19 that was typical of recent infection. In the absence of other positive data, the possibility of a correlation between the tenth nerve palsy and parvovirus infection is discussed.

  19. Isolation and characterization of cobalt-sensitive mutant of Neurospora crassa

    Directory of Open Access Journals (Sweden)

    Krishnapuram Rashmi

    2014-12-01

    Full Text Available Objective: To isolate and demonstrate the mechanism of metal transport in cobalt-sensitive mutant (CSM of Neurospora crassa (N. crassa. Methods: Isolation of CSM of N. crassa, I50 determination, growth measurements, metal ion uptake studies and sexual crosses were performed to determine the mechanism of sensitivity and locus. Results: CSMs of N. crassa were isolated by mutagenesis with diethyl sulfate. More than 500 isolates were screened and out of these isolates, CSM-I was 5-fold and CSM-II was 10-fold sensitive to Co on liquid medium as compared to the wild type. Compositional analysis of cell wall revealed the decrease in total phosphate content. N. crassa CSM bound much less cobalt to cell wall fraction than wild type. The data indicated closer linkage between resistance and mating type locus (mat, which is, located on LG I. Conclusions: A CSM of N. crassa is 5-fold more sensitive than wild type and cross sensitive to nickel and copper and hyper-accumulates 2-4 fold more toxic metal ions over wild type. The mechanism for sensitivity is decreased in cobalt-binding to cell wall fraction and increased intracellular uptake. N. crassa-acon-3 morphologically resembles the CSM, cobalt-sensitive and maps to similar locus.

  20. Electrochemical functionalization of glassy carbon electrode by reduction of diazonium cations in protic ionic liquid

    International Nuclear Information System (INIS)

    Shul, Galyna; Ruiz, Carlos Alberto Castro; Rochefort, Dominic; Brooksby, Paula A.; Bélanger, Daniel

    2013-01-01

    Protic ionic liquid based on 2-methoxypyridine and trifluoroacetic acid was used as electrolyte for the functionalization of a glassy carbon electrode surface by electrochemical reduction of in situ generated 4-chlorobenzene diazonium and 4-nitrobenzene diazonium cations. The diazonium cations were synthesized in an electrochemical cell by reaction of the corresponding amines with NaNO 2 dissolved in protic ionic liquid. The resulting electrografted organic layers exhibit similar properties to those layers obtained by the derivatization from isolated diazonium salts dissolved in protic ionic liquid. Functionalized glassy carbon electrode surfaces were characterized by cyclic voltammetry, Fourier transform infrared and X-ray photoelectron spectroscopies. Atomic force microscopy thickness measurements revealed that, in our experimental conditions, the use of protic ionic liquid led to the formation of film with a thickness of about 1.5 nm. It is also demonstrated that the nitrobenzene chemisorbed on glassy carbon electrode or dissolved in protic ionic liquid undergoes electrochemical conversion to hydroxyaminobenzene

  1. Clinical isolates of Enterococcus faecium exhibit strain-specific collagen binding mediated by Acm, a new member of the MSCRAMM family.

    Science.gov (United States)

    Nallapareddy, Sreedhar R; Weinstock, George M; Murray, Barbara E

    2003-03-01

    A collagen-binding adhesin of Enterococcus faecium, Acm, was identified. Acm shows 62% similarity to the Staphylococcus aureus collagen adhesin Cna over the entire protein and is more similar to Cna (60% and 75% similarity with Cna A and B domains respectively) than to the Enterococcus faecalis collagen-binding adhesin, Ace, which shares homology with Acm only in the A domain. Despite the detection of acm in 32 out of 32 E. faecium isolates, only 11 of these (all clinical isolates, including four vancomycin-resistant endocarditis isolates and seven other isolates) exhibited binding to collagen type I (CI). Although acm from three CI-binding vancomycin-resistant E. faecium clinical isolates showed 100% identity, analysis of acm genes and their promoter regions from six non-CI-binding strains identified deletions or mutations that introduced stop codons and/or IS elements within the gene or the promoter region in five out of six strains, suggesting that the presence of an intact functional acm gene is necessary for binding of E. faecium strains to CI. Recombinant Acm A domain showed specific and concentration-dependent binding to collagen, and this protein competed with E. faecium binding to immobilized CI. Consistent with the adherence phenotype and sequence data, probing with Acm-specific IgGs purified from anti-recombinant Acm A polyclonal rabbit serum confirmed the surface expression of Acm in three out of three collagen-binding clinical isolates of E. faecium tested, but in none of the strains with a non-functional pseudo acm gene. Introduction of a functional acm gene into two non-CI-binding natural acm mutant strains conferred a CI-binding phenotype, further confirming that native Acm is sufficient for the binding of E. faecium to CI. These results demonstrate that acm, which encodes a potential virulence factor, is functional only in certain infection-derived clinical isolates of E. faecium, and suggest that Acm is the primary adhesin responsible for the

  2. Liquid-liquid phase transition in Stillinger-Weber silicon

    International Nuclear Information System (INIS)

    Beaucage, Philippe; Mousseau, Normand

    2005-01-01

    It was recently demonstrated that Stillinger-Weber silicon undergoes a liquid-liquid first-order phase transition deep into the supercooled region (Sastry and Angell 2003 Nat. Mater. 2 739). Here we study the effects of perturbations on this phase transition. We show that the order of the liquid-liquid transition changes with negative pressure. We also find that the liquid-liquid transition disappears when the three-body term of the potential is strengthened by as little as 5%. This implies that the details of the potential could affect strongly the nature and even the existence of the liquid-liquid phase

  3. Analytical concepts for health management systems of liquid rocket engines

    Science.gov (United States)

    Williams, Richard; Tulpule, Sharayu; Hawman, Michael

    1990-01-01

    Substantial improvement in health management systems performance can be realized by implementing advanced analytical methods of processing existing liquid rocket engine sensor data. In this paper, such techniques ranging from time series analysis to multisensor pattern recognition to expert systems to fault isolation models are examined and contrasted. The performance of several of these methods is evaluated using data from test firings of the Space Shuttle main engines.

  4. Bank liquidity risk management: A South African survey to determine future change

    Directory of Open Access Journals (Sweden)

    S. Claassen

    2012-09-01

    Full Text Available In 2008 the global financial system and, more particularly, the world banking system suffered a financial crisis worse than any earlier crises. The financial crunch brought to light that liquidity risk management in banks poses a problem, and that the world’s financial institutions will have to change their current practices as it relates to this risk. Apart from the importance of liquidity and the risk that it may cause, the integrated nature of all risks made banks more aware of the fact that none of these risks can be managed in isolation. For various reasons, South African banks were not as exposed to the problems experienced in the global context. However, SA banks may have learned new lessons from the crisis and may plan to change the way they manage liquidity risk in particular, in the future. In order to determine how SA banks perceive liquidity management and liquidity risk, a survey of all SA banks was carried out. The majority of respondents indicated that the financial crisis reminded them of the importance of liquidity risk management in the South African banking system as well as the global banking system. The majority of banks rate all the liquidity risk management tools as extremely important and rate corporate governance, strategy, policy and risk tolerance, liquidity risk measurement and intra-day liquidity as their number one priority. Basel III is generally perceived as being effective, but 30% of respondents perceived it as neither effective nor ineffective, because South African banks already have similar measures in place

  5. Human surfactant protein D: SP-D contains a C-type lectin carbohydrate recognition domain.

    Science.gov (United States)

    Rust, K; Grosso, L; Zhang, V; Chang, D; Persson, A; Longmore, W; Cai, G Z; Crouch, E

    1991-10-01

    Lung surfactant protein D (SP-D) shows calcium-dependent binding to specific saccharides, and is similar in domain structure to certain members of the calcium-dependent (C-type) lectin family. Using a degenerate oligomeric probe corresponding to a conserved peptide sequence derived from the amino-terminus of the putative carbohydrate binding domain of rat and bovine SP-D, we screened a human lung cDNA library and isolated a 1.4-kb cDNA for the human protein. The relationship of the cDNA to SP-D was established by several techniques including amino-terminal microsequencing of SP-D-derived peptides, and immunoprecipitation of translation products of transcribed mRNA with monospecific antibodies to SP-D. In addition, antibodies to a synthetic peptide derived from a predicted unique epitope within the carbohydrate recognition domain of SP-D specifically reacted with SP-D. DNA sequencing demonstrated a noncollagenous carboxy-terminal domain that is highly homologous with the carboxy-terminal globular domain of previously described C-type lectins. This domain contains all of the so-called "invariant residues," including four conserved cysteine residues, and shows high homology with the mannose-binding subfamily of C-type lectins. Sequencing also demonstrated an amino-terminal collagenous domain that contains an uninterrupted sequence of 59 Gly-X-Y triplets and that also contains the only identified consensus for asparagine-linked oligosaccharides. The studies demonstrate that SP-D is a member of the C-type lectin family, and confirm predicted structural similarities to conglutinin, SP-D, and the serum mannose binding proteins.

  6. Domain architecture of protein-disulfide isomerase facilitates its dual role as an oxidase and an isomerase in Ero1p-mediated disulfide formation

    DEFF Research Database (Denmark)

    Kulp, M. S.; Frickel, E. M.; Ellgaard, Lars

    2006-01-01

    reduction/rearrangement of non-native disulfides is poorly understood. We analyzed the role of individual PDI domains in disulfide bond formation in a reaction driven by their natural oxidant, Ero1p. We found that Ero1p oxidizes the isolated PDI catalytic thioredoxin domains, A and A' at the same rate......Native disulfide bond formation in eukaryotes is dependent on protein-disulfide isomerase (PDI) and its homologs, which contain varying combinations of catalytically active and inactive thioredoxin domains. However, the specific contribution of PDI to the formation of new disulfides versus...... catalytic (A) domain. The specific order of thioredoxin domains in PDI is important in establishing the asymmetry in the rate of oxidation of the two active sites thus allowing A and A', two thioredoxin domains that are similar in sequence and structure, to serve opposing functional roles as a disulfide...

  7. Solid-Liquid and Liquid-Liquid Equilibrium in the Formamide-Acetophenone System.

    Czech Academy of Sciences Publication Activity Database

    Malijevská, I.; Sedláková, Zuzana; Řehák, K.; Vrbka, P.

    2006-01-01

    Roč. 71, 9 (2006) , s. 1350-1358 ISSN 0010-0765 Institutional research plan: CEZ:AV0Z40720504 Keywords : solid-liquid equilibria * liquid-liquid equilibria * metastable Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 0.881, year: 2006

  8. Effect of electric and magnetic fields on current-voltage characteristics of a lyotropic liquid crystal

    International Nuclear Information System (INIS)

    Minasyants, M.Kh.; Badalyan, G. G.; Shahinian, A. A.

    1997-01-01

    The effect of electric and magnetic fields on current-voltage characteristics is studied for the lamellar phase in the lyotropic liquid-crystal sodium pentadecylsulfonate (SPDS)-water and lecithin-water systems. It has been found that the current-voltage characteristics of both systems have hysteresis. In the case of ionogenic SPDS, the hysteresis is formed due to ion current caused by the spatial reorientation of domains consisting of parallel lamellar fragments; in the case of lecithin, whose molecules contain dipoles, the hysteresis is formed due to the spatial reorientation of domains caused by the interaction of the resultant dipole moment of the domains with the electric field. It is shown that the introduction into lamellae of cetylpyridine bromide, which has an intrinsic magnetic moment, changes the resultant magnetic moment of domains and, thus, also the hysteresis loop of the current-voltage characteristic. The systems studied show the 'memory' effect with respect to both the electric and magnetic fields. Field-induced processes of domain reorientation were recorded by the method of small-angle x-ray scattering

  9. Passive immunization of pigs with bispecific llama single-domain antibody fragments against foot-and-mouth disease and porcine immunoglobulin

    NARCIS (Netherlands)

    Harmsen, M.M.; Fijten, H.P.D.; Dekker, A.; Eble, P.L.

    2008-01-01

    Foot-and-mouth disease (FMD) is a contagious viral disease of cloven-hoofed animals that occasionally causes outbreaks in Europe. We aim to develop an immunotherapy that confers rapid protection against FMD in outbreak situations. For this purpose, we previously isolated llama single-domain antibody

  10. Expression of Aspergillus hemoglobin domain activities in Aspergillus oryzae grown on solid substrates improves growth rate and enzyme production

    NARCIS (Netherlands)

    Biesebeke, te R.; Boussier, A.; Biezen van, N.; Braaksma, M.; Hondel, van den C.A.M.J.J.; Vos, de W.M.; Punt, P.J.

    2006-01-01

    DNA fragments coding for hemoglobin domains (HBD) were isolated from Aspergillus oryzae and Aspergillus niger. The HBD activities were expressed in A. oryzae by introduction of HBD gene fragments under the control of the promoter of the constitutively expressed gpdA gene. In the transformants,

  11. Directed evolution of the TALE N-terminal domain for recognition of all 5′ bases

    Science.gov (United States)

    Lamb, Brian M.; Mercer, Andrew C.; Barbas, Carlos F.

    2013-01-01

    Transcription activator-like effector (TALE) proteins can be designed to bind virtually any DNA sequence. General guidelines for design of TALE DNA-binding domains suggest that the 5′-most base of the DNA sequence bound by the TALE (the N0 base) should be a thymine. We quantified the N0 requirement by analysis of the activities of TALE transcription factors (TALE-TF), TALE recombinases (TALE-R) and TALE nucleases (TALENs) with each DNA base at this position. In the absence of a 5′ T, we observed decreases in TALE activity up to >1000-fold in TALE-TF activity, up to 100-fold in TALE-R activity and up to 10-fold reduction in TALEN activity compared with target sequences containing a 5′ T. To develop TALE architectures that recognize all possible N0 bases, we used structure-guided library design coupled with TALE-R activity selections to evolve novel TALE N-terminal domains to accommodate any N0 base. A G-selective domain and broadly reactive domains were isolated and characterized. The engineered TALE domains selected in the TALE-R format demonstrated modularity and were active in TALE-TF and TALEN architectures. Evolved N-terminal domains provide effective and unconstrained TALE-based targeting of any DNA sequence as TALE binding proteins and designer enzymes. PMID:23980031

  12. Diddensiella caesifluorescens gen. nov., sp. nov., a riboflavin-producing yeast species of the family Trichomonascaceae

    Science.gov (United States)

    Four strains of a novel heterothallic yeast species were isolated from rotten wood collected in or near the Pilis Mountains in Hungary. The strains produced riboflavin in liquid culture. Analysis of gene sequences for the D1/D2 domains of the large subunit nuclear ribosomal RNA (rRNA), as well as an...

  13. Macromolecular sensing at the liquid-liquid interface

    Energy Technology Data Exchange (ETDEWEB)

    Herzog, Gregoire; Flynn, Shane [Tyndall National Institute, Lee Maltings, University College, Cork (Ireland); Arrigan, Damien W M, E-mail: gregoire.herzog@tyndall.ie [Nanochemistry Research Institute, Department of Chemistry, Curtin University, Perth (Australia)

    2011-08-17

    We report here the electrochemical sensing of macromolecules, such as polyLysine dendrimers, at the polarised liquid | liquid interface. Electrochemistry at the liquid | liquid interface is a powerful analytical technique which allows the detection of non-redox active molecules via ion transfer reactions at a polarised water - oil interface. We demonstrate here that different parameters of the polyLysine dendrimers (charge number, molecular weight) have a strong influence on the sensitivity and limit of detection of these macromolecules. This work will help to the development of sensors based on charge transfer at the liquid | liquid interface.

  14. Macromolecular sensing at the liquid-liquid interface

    International Nuclear Information System (INIS)

    Herzog, Gregoire; Flynn, Shane; Arrigan, Damien W M

    2011-01-01

    We report here the electrochemical sensing of macromolecules, such as polyLysine dendrimers, at the polarised liquid | liquid interface. Electrochemistry at the liquid | liquid interface is a powerful analytical technique which allows the detection of non-redox active molecules via ion transfer reactions at a polarised water - oil interface. We demonstrate here that different parameters of the polyLysine dendrimers (charge number, molecular weight) have a strong influence on the sensitivity and limit of detection of these macromolecules. This work will help to the development of sensors based on charge transfer at the liquid | liquid interface.

  15. Antimicrobial activity of a novel hypervariable immunoglobulin domain-containing receptor Dscam in Cherax quadricarinatus.

    Science.gov (United States)

    Li, Dan; Yu, Ai-Qing; Li, Xue-Jie; Zhu, You-Ting; Jin, Xing-Kun; Li, Wei-Wei; Wang, Qun

    2015-12-01

    Down syndrome cell adhesion molecule (Dscam) mediates innate immunity against pathogens in arthropods. Here, a novel Dscam from red claw crayfish Cherax quadricarinatus (CqDscam) was isolated. The CqDscam protein contains one signal peptide, ten immunoglobulin domains, six fibronectin type III domains, one transmembrane domain and cytoplasmic tail. CqDscam phylogenetically clustered with other invertebrate Dscams. Variable regions of CqDscam in N-terminal halves of Ig2 and Ig3 domains, complete Ig7 domain and TM domain can be reshuffled after transcription to produce a deluge of >37,620 potential alternative splice forms. CqDscam was detected in all tissues tested and abundantly expressed in immune system and nerve system. Upon lipopolysaccharides (LPS) and b-1, 3-glucans (Glu) challenged, the expression of CqDscam was up-regulated, while no response in expression occurred after injection with peptidoglycans (PG). Membrane-bound and secreted types of CqDscam were separated on the protein level, and were both extensively induced post LPS challenge. Membrane-bound CqDscam protein was not detected in the serum, but localized to the hemocyte surface by immuno-localization assay. In the antimicrobial assays, the recombinant LPS-induced isoform of CqDscam protein displayed bacterial binding and growth inhibitory activities, especially with Escherichia coli. These results suggested that CqDscam, as one of pattern-recognition receptors (PRRs), involved in innate immune recognition and defense mechanisms in C. quadricarinatus, possibly through alternative splicing. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Molecular characterization of Mycoplasma synoviae isolates from commercial chickens in Iran

    Directory of Open Access Journals (Sweden)

    Pourbakhsh

    2014-05-01

    Full Text Available Detection of Mycoplasma synoviae (MS by culture and polymerase chain reaction (PCR has been reported from commercial chicken farms in different provinces of Iran. In some reports the phylogenetic analysis of MS isolates based on 16S rRNA and variable lipoprotein hemagglutinin (vlhA genes have been carried out. The PCR product containing partial 16S rRNA genes of Iranain isolates was sequenced, and compared with 16S rRNA gene of MS sequences which were available in GenBank. Variations, polymorphisms, and differences between nucleotides of all isolates were observed. Phylogenetic analysis of these sequences showed that all MS isolates from Iran were most closely related to sequences of MS from Brazil. Sequence analysis of the N-terminal end of the hemagglutinin encoding gene vlhA were also used as an alternative for the detection and initial typing of field strains of MS in commercial poultry. The results showed that there was a complete concordance between all Iranian isolates nucleotide sequence and the 5́-vlhA region sequence remained unchanged in all MS isolates and demonstrated differentiation between Iranian isolates and live commercial MS-H vaccine strain. More recently, the single-copy domain of the conserved region of vlhA gene in MS was sequenced, analyzed and verified to type MS field isolates in Iran and live vaccine MS-H strain. In addition, a restriction fragment length polymorphism (RFLP method was established based on single nucleotide polymorphism that existed in all field isolates of Iran to differentiate between these field isolates and MS-H. This PCR-RFLP method allowed differentiating all MS field isolates from the vaccine strain.

  17. Concrete domains

    OpenAIRE

    Kahn, G.; Plotkin, G.D.

    1993-01-01

    This paper introduces the theory of a particular kind of computation domains called concrete domains. The purpose of this theory is to find a satisfactory framework for the notions of coroutine computation and sequentiality of evaluation.

  18. A method for the isolation of root hairs from the model legume Medicago truncatula

    NARCIS (Netherlands)

    Ramos Escribano, J.; Bisseling, T.

    2003-01-01

    A new method for the isolation of root hairs from the model legume, Medicago truncatula, was developed. The procedure involves the propagation of detached roots on agar plates and the collection of root hairs by immersion in liquid nitrogen. Yields of up to 40 µg of root hair protein were obtained

  19. Domain configuration and magnetization switching in arrays of permalloy nanostripes

    International Nuclear Information System (INIS)

    Iglesias-Freire, Ó.; Jaafar, M.; Pérez, L.; Abril, O. de; Vázquez, M.; Asenjo, A.

    2014-01-01

    The proximity effect in the collective behavior of arrays of magnetic nanostripes is currently a subject of intensive research. The imperative of reducing the size and distances between elements in order to achieve higher storage capacity, faster access to the information as well as low energy consumption, brings consequences about the isolated behavior of the elements and devices. Parallel to each other permalloy nanostripes with high aspect ratio have been prepared by the nanolithography technique. The evolution of the closure domains and the magnetization direction in individual nanostructures has been imaged under applied magnetic fields using Variable Field Magnetic Force Microscopy. Moreover, the magnetostatic interactions between neighboring elements and the proximity effects in arrays of such nanostructures have been quantitatively analyzed by Magnetic Force Microscopy and micromagnetic simulations. The agreement between simulations and the experimental results allows us to conclude the relevance of those interactions depending on the geometry characteristics. In particular, results suggest that the magnetostatic coupling between adjacent nanostripes vanishes for separation distances higher than 500 nm. - Highlights: • A shape anisotropy-induced single domain remanent state is present in the stripes. Closure domains are formed under external fields. • Separation distances between neighboring stripes (500 nm) are enough to overcome the magnetostatic coupling and avoid a multi-stripe character. • Micromagnetic simulations predict critical distances of around 500 nm for the onset of magnetostatic coupling between neighboring elements. • Simulations predict stripes with a small longitudinal separation to behave as single elements, with domain walls “jumping” between them

  20. Domain configuration and magnetization switching in arrays of permalloy nanostripes

    Energy Technology Data Exchange (ETDEWEB)

    Iglesias-Freire, Ó., E-mail: aasenjo@icmm.csic.es [Instituto de Ciencia de Materiales de Madrid, CSIC, Sor Juana Inés de la Cruz 3, Madrid 28049 (Spain); Jaafar, M. [Instituto de Ciencia de Materiales de Madrid, CSIC, Sor Juana Inés de la Cruz 3, Madrid 28049 (Spain); Dpto. Física de la Materia Condensada, Universidad Autónoma de Madrid, Cantoblanco 28049 (Spain); Pérez, L. [Dpto. Física de Materiales, Universidad Complutense de Madrid, Madrid 28040 (Spain); Abril, O. de [Dpto. Física e Instalaciones Aplicadas a la Edificación, al Medio Ambiente y al Urbanismo, Universidad Politécnica de Madrid, Madrid 28040 (Spain); Vázquez, M.; Asenjo, A. [Instituto de Ciencia de Materiales de Madrid, CSIC, Sor Juana Inés de la Cruz 3, Madrid 28049 (Spain)

    2014-04-15

    The proximity effect in the collective behavior of arrays of magnetic nanostripes is currently a subject of intensive research. The imperative of reducing the size and distances between elements in order to achieve higher storage capacity, faster access to the information as well as low energy consumption, brings consequences about the isolated behavior of the elements and devices. Parallel to each other permalloy nanostripes with high aspect ratio have been prepared by the nanolithography technique. The evolution of the closure domains and the magnetization direction in individual nanostructures has been imaged under applied magnetic fields using Variable Field Magnetic Force Microscopy. Moreover, the magnetostatic interactions between neighboring elements and the proximity effects in arrays of such nanostructures have been quantitatively analyzed by Magnetic Force Microscopy and micromagnetic simulations. The agreement between simulations and the experimental results allows us to conclude the relevance of those interactions depending on the geometry characteristics. In particular, results suggest that the magnetostatic coupling between adjacent nanostripes vanishes for separation distances higher than 500 nm. - Highlights: • A shape anisotropy-induced single domain remanent state is present in the stripes. Closure domains are formed under external fields. • Separation distances between neighboring stripes (500 nm) are enough to overcome the magnetostatic coupling and avoid a multi-stripe character. • Micromagnetic simulations predict critical distances of around 500 nm for the onset of magnetostatic coupling between neighboring elements. • Simulations predict stripes with a small longitudinal separation to behave as single elements, with domain walls “jumping” between them.