Sample records for type strain xt

  1. Physical-Mechanical Properties of a Fiber-Reinforced Composite Based on an ELUR-P Carbon Tape and XT-118 Binder

    NASA Astrophysics Data System (ADS)

    Paimushin, V. N.; Kholmogorov, S. A.

    2018-03-01

    A series of tests to identify the physical-mechanical properties of a unidirectional carbon-fiber-reinforced composite based on an ELUR-P carbon fibers and an XT-118 epoxy binder were performed. The form of the stress-strain diagrams of specimens loaded in tension in the longitudinal, transverse, and ±45° directions and in compression in the longitudinal and ±45° directions were examined. Tensile diagrams were also determined for the XT-118 binder alone. The relation between the tangential shear modulus and shear strains of the composite was highly nonlinear from the very beginning of loading and depended on the loading type. Such a nonlinear response of the carbon-fiber-reinforced composite in shear cannot be the result of plastic deformation of binder, but can be explained only by structural changes caused by the inner buckling instability of the composite at micro- and mesolevels..

  2. Testudinibacter aquarius gen. nov., sp. nov., a member of the family Pasteurellaceae isolated from the oral cavity of freshwater turtles.

    PubMed

    Hansen, Mie Johanne; Pennanen, Elin Anna Erica; Bojesen, Anders Miki; Christensen, Henrik; Bertelsen, Mads Frost

    2016-02-01

    A total of 13 Pasteurellaceae isolates from healthy freshwater turtles were characterized by genotypic and phenotypic tests. Phylogenetic analysis of partial 16S rRNA and rpoB gene sequences showed that the isolates investigated formed a monophyletic group. The closest related species based on 16S rRNA gene sequencing was Chelonobacter oris CCUG 55632T with 94.4 % similarity and the closest related species based on rpoB gene sequence comparison was [Pasteurella] testudinis CCUG 19802T with 91.5 % similarity. All the investigated isolates exhibited phenotypic characteristics of the family Pasteurellaceae. However, they could be separated from existing genera of the Pasteurellaceae by the following test results: indole, ornithine decarboxylase and Voges-Proskauer positive; and methyl red, urease and PNPG (α-glucosidase) negative. No X- or V-factor requirement was observed. A zone of β-haemolysis surrounded the colonies after 24 h of incubation on bovine blood agar at 37 °C. Acid was produced from l-arabinose, dulcitol, d-mannitol, sucrose and trehalose. Representative strain ELNT2xT had a fatty acid profile that was characteristic for members of the Pasteurellaceae. ELNT2xT expressed only one respiratory quinone, ubiquinone-8 (100 %). The DNA G+C content of strain ELNT2xT was 42.8 mol%. On the basis of both phylogenetic and phenotypic evidence, it is proposed that the strains should be classified as representatives of a novel species of a new genus, Testudinibacter aquarius gen. nov., sp. nov. The type strain of Testudinibacter aquarius is ELNT2xT ( = CCUG 65146T = DSM 28140T), which was isolated from the oral cavity of a captive eastern long-necked turtle (Chelodina longicollis) in Denmark in 2012.

  3. Thermophilic fermentation of acetoin and 2,3-butanediol by a novel Geobacillus strain

    PubMed Central

    2012-01-01

    Background Acetoin and 2,3-butanediol are two important biorefinery platform chemicals. They are currently fermented below 40°C using mesophilic strains, but the processes often suffer from bacterial contamination. Results This work reports the isolation and identification of a novel aerobic Geobacillus strain XT15 capable of producing both of these chemicals under elevated temperatures, thus reducing the risk of bacterial contamination. The optimum growth temperature was found to be between 45 and 55°C and the medium initial pH to be 8.0. In addition to glucose, galactose, mannitol, arabionose, and xylose were all acceptable substrates, enabling the potential use of cellulosic biomass as the feedstock. XT15 preferred organic nitrogen sources including corn steep liquor powder, a cheap by-product from corn wet-milling. At 55°C, 7.7 g/L of acetoin and 14.5 g/L of 2,3-butanediol could be obtained using corn steep liquor powder as a nitrogen source. Thirteen volatile products from the cultivation broth of XT15 were identified by gas chromatography–mass spectrometry. Acetoin, 2,3-butanediol, and their derivatives including a novel metabolite 2,3-dihydroxy-3-methylheptan-4-one, accounted for a total of about 96% of all the volatile products. In contrast, organic acids and other products were minor by-products. α-Acetolactate decarboxylase and acetoin:2,6-dichlorophenolindophenol oxidoreductase in XT15, the two key enzymes in acetoin metabolic pathway, were found to be both moderately thermophilic with the identical optimum temperature of 45°C. Conclusions Geobacillus sp. XT15 is the first naturally occurring thermophile excreting acetoin and/or 2,3-butanediol. This work has demonstrated the attractive prospect of developing it as an industrial strain in the thermophilic fermentation of acetoin and 2,3-butanediol with improved anti-contamination performance. The novel metabolites and enzymes identified in XT15 also indicated its strong promise as a precious biological resource. Thermophilic fermentation also offers great prospect for improving its yields and efficiencies. This remains a core aim for future work. PMID:23217110

  4. Gene expression and localization of two types of AQP5 in Xenopus tropicalis under hydration and dehydration.

    PubMed

    Shibata, Yuki; Sano, Takahiro; Tsuchiya, Nobuhito; Okada, Reiko; Mochida, Hiroshi; Tanaka, Shigeyasu; Suzuki, Masakazu

    2014-07-01

    Two types of aquaporin 5 (AQP5) genes (aqp-xt5a and aqp-xt5b) were identified in the genome of Xenopus tropicalis by synteny comparison and molecular phylogenetic analysis. When the frogs were in water, AQP-xt5a mRNA was expressed in the skin and urinary bladder. The expression of AQP-xt5a mRNA was significantly increased in dehydrated frogs. AQP-xt5b mRNA was also detected in the skin and increased in response to dehydration. Additionally, AQP-xt5b mRNA began to be slightly expressed in the lung and stomach after dehydration. For the pelvic skin of hydrated frogs, immunofluorescence staining localized AQP-xt5a and AQP-xt5b to the cytoplasm of secretory cells of the granular glands and the apical plasma membrane of secretory cells of the small granular glands, respectively. After dehydration, the locations of both AQPs in their respective glands did not change, but AQP-xt5a was visualized in the cytoplasm of secretory cells of the small granular glands. For the urinary bladder, AQP-xt5a was observed in the apical plasma membrane and cytoplasm of a number of granular cells under normal hydration. After dehydration, AQP-xt5a was found in the apical membrane and cytoplasm of most granular cells. Injection of vasotocin into hydrated frogs did not induce these changes in the localization of AQP-xt5a in the small granular glands and urinary bladder, however. The results suggest that AQP-xt5a might be involved in water reabsorption from the urinary bladder during dehydration, whereas AQP-xt5b might play a role in water secretion from the small granular gland. Copyright © 2014 the American Physiological Society.

  5. Abnormal Positioning of Diencephalic Cell Types in Neocortical Tissue in the Dorsal Telencephalon of Mice Lacking Functional Gli3

    PubMed Central

    Fotaki, Vassiliki; Yu, Tian; Zaki, Paulette A.; Mason, John O.; Price, David J.

    2008-01-01

    The transcription factor Gli3 (glioma-associated oncogene homolog) is essential for normal development of the mammalian forebrain. One extreme requirement for Gli3 is at the dorsomedial telencephalon, which does not form in Gli3Xt/Xt mutant mice lacking functional Gli3. In this study, we analyzed expression of Gli3 in the wild-type telencephalon and observed a highdorsal-to-lowventral gradient of Gli3 expression and predominance of the cleaved form of the Gli3 protein dorsally. This graded expression correlates with the severedorsal-to-mildventral telencephalic phenotype observed in Gli3Xt/Xt mice. We characterized the abnormal joining of the telencephalon to the diencephalon and defined the medial limit of the dorsal telencephalon in Gli3Xt/Xt mice early in corticogenesis. Based on this analysis, we concluded that some of the abnormal expression of ventral telencephalic markers previously described as being in the dorsal telencephalon is, in fact, expression in adjacent diencephalic tissue, which expresses many of the same genes that mark the ventral telencephalon. We observed occasional cells with diencephalic character in the Foxg1 (forkhead box)-expressing Gli3Xt/Xt telencephalon at embryonic day 10.5, a day after the anatomical subdivision of the forebrain vesicle. Large clusters of such cells appear in the Gli3Xt/Xt neocortical region at later ages, when the neocortex becomes highly disorganized, forming rosettes comprising mainly neural progenitors. We propose that Gli3 is indispensable for formation of an intact telencephalic-diencephalic boundary and for preventing the abnormal positioning of diencephalic cells in the dorsal telencephalon. PMID:16957084

  6. Ada/Xt Architecture: Design Report for the Software Technology for Adaptable, Reliable Systems (STARS)

    DTIC Science & Technology

    1990-01-25

    N Task: UR20 CDRL: 01000 N UR2O--ProcesslEnvironmentx Ada/Xt. Architecture : Design Report ~ ~ fFCp Informal Technical Data I? ,LECp Sofwar Tehoog for...S. FUNDING NUMBERS Ada/Xt Architecture : Design Report STARS Contract 6.AUTHOR(S)_ Ft9628-88-D-0031 6. AUTHOR(S) Kurt Wallnau 7. PERFORMING...of the STARS Prime contract under the Process Environment Integration task (UR20). This document "Ada Xt Architecture : Design Report", type A005

  7. Diffuse-interface polycrystal plasticity: expressing grain boundaries as geometrically necessary dislocations

    NASA Astrophysics Data System (ADS)

    Admal, Nikhil Chandra; Po, Giacomo; Marian, Jaime

    2017-12-01

    The standard way of modeling plasticity in polycrystals is by using the crystal plasticity model for single crystals in each grain, and imposing suitable traction and slip boundary conditions across grain boundaries. In this fashion, the system is modeled as a collection of boundary-value problems with matching boundary conditions. In this paper, we develop a diffuse-interface crystal plasticity model for polycrystalline materials that results in a single boundary-value problem with a single crystal as the reference configuration. Using a multiplicative decomposition of the deformation gradient into lattice and plastic parts, i.e. F( X,t)= F L( X,t) F P( X,t), an initial stress-free polycrystal is constructed by imposing F L to be a piecewise constant rotation field R 0( X), and F P= R 0( X)T, thereby having F( X,0)= I, and zero elastic strain. This model serves as a precursor to higher order crystal plasticity models with grain boundary energy and evolution.

  8. Evaluation of red blood cell and platelet antigen genotyping platforms (ID CORE XT/ID HPA XT) in routine clinical practice.

    PubMed

    Finning, Kirstin; Bhandari, Radhika; Sellers, Fiona; Revelli, Nicoletta; Villa, Maria Antonietta; Muñiz-Díaz, Eduardo; Nogués, Núria

    2016-03-01

    High-throughput genotyping platforms enable simultaneous analysis of multiple polymorphisms for blood group typing. BLOODchip® ID is a genotyping platform based on Luminex® xMAP technology for simultaneous determination of 37 red blood cell (RBC) antigens (ID CORE XT) and 18 human platelet antigens (HPA) (ID HPA XT) using the BIDS XT software. In this international multicentre study, the performance of ID CORE XT and ID HPA XT, using the centres' current genotyping methods as the reference for comparison, and the usability and practicality of these systems, were evaluated under working laboratory conditions. DNA was extracted from whole blood in EDTA with Qiagen methodologies. Ninety-six previously phenotyped/genotyped samples were processed per assay: 87 testing samples plus five positive controls and four negative controls. Results were available for 519 samples: 258 with ID CORE XT and 261 with ID HPA XT. There were three "no calls" that were either caused by human error or resolved after repeating the test. Agreement between the tests and reference methods was 99.94% for ID CORE XT (9,540/9,546 antigens determined) and 100% for ID HPA XT (all 4,698 alleles determined). There were six discrepancies in antigen results in five RBC samples, four of which (in VS, N, S and Do(a)) could not be investigated due to lack of sufficient sample to perform additional tests and two of which (in S and C) were resolved in favour of ID CORE XT (100% accuracy). The total hands-on time was 28-41 minutes for a batch of 16 samples. Compared with the reference platforms, ID CORE XT and ID HPA XT were considered simpler to use and had shorter processing times. ID CORE XT and ID HPA XT genotyping platforms for RBC and platelet systems were accurate and user-friendly in working laboratory settings.

  9. Software Technology for Adaptable, Reliable Systems (STARS) (User Manual). Ada Command Environment (ACE) Version 8.0 Sun OS Implementation

    DTIC Science & Technology

    1990-10-29

    the equivalent type names in the basic X libary . 37. Intrinsics Contains the type declarations common to all Xt toolkit routines. 38. Widget-Package...Memory-Size constant Integer 1; MinInt constant I-reger Integer’First; MaxInt const-i’ integer Integer’Last; -- Max- Digits constant Integer 1; -- MaxMan...connection between some type names used by Xt routines and the equivalent type names in the basic X libary . .package RenamedXlibTypes is P;’ge 65 29

  10. Well-posedness for a class of doubly nonlinear stochastic PDEs of divergence type

    NASA Astrophysics Data System (ADS)

    Scarpa, Luca

    2017-08-01

    We prove well-posedness for doubly nonlinear parabolic stochastic partial differential equations of the form dXt - div γ (∇Xt) dt + β (Xt) dt ∋ B (t ,Xt) dWt, where γ and β are the two nonlinearities, assumed to be multivalued maximal monotone operators everywhere defined on Rd and R respectively, and W is a cylindrical Wiener process. Using variational techniques, suitable uniform estimates (both pathwise and in expectation) and some compactness results, well-posedness is proved under the classical Leray-Lions conditions on γ and with no restrictive smoothness or growth assumptions on β. The operator B is assumed to be Hilbert-Schmidt and to satisfy some classical Lipschitz conditions in the second variable.

  11. Structure determination of the extracellular xylanase from Geobacillus stearothermophilus by selenomethionyl MAD phasing.

    PubMed

    Teplitsky, A; Mechaly, A; Stojanoff, V; Sainz, G; Golan, G; Feinberg, H; Gilboa, R; Reiland, V; Zolotnitsky, G; Shallom, D; Thompson, A; Shoham, Y; Shoham, G

    2004-05-01

    Xylanases are hemicellulases that hydrolyze the internal beta-1,4-glycoside bonds of xylan. The extracellular thermostable endo-1,4-beta-xylanase (EC 3.2.1.8; XT6) produced by the thermophilic bacterium Geobacillus stearothermophilus T-6 was shown to bleach pulp optimally at pH 9 and 338 K and was successfully used in a large-scale biobleaching mill trial. The xylanase gene was cloned and sequenced. The mature enzyme consists of 379 amino acids, with a calculated molecular weight of 43 808 Da and a pI of 9.0. Crystallographic studies of XT6 were performed in order to study the mechanism of catalysis and to provide a structural basis for the rational introduction of enhanced thermostability by site-specific mutagenesis. XT6 was crystallized in the primitive trigonal space group P3(2)21, with unit-cell parameters a = b = 112.9, c = 122.7 A. A full diffraction data set for wild-type XT6 has been measured to 2.4 A resolution on flash-frozen crystals using synchrotron radiation. A fully exchanged selenomethionyl XT6 derivative (containing eight Se atoms per XT6 molecule) was also prepared and crystallized in an isomorphous crystal form, providing full selenium MAD data at three wavelengths and enabling phase solution and structure determination. The structure of wild-type XT6 was refined at 2.4 A resolution to a final R factor of 15.6% and an R(free) of 18.6%. The structure demonstrates that XT6 is made up of an eightfold TIM-barrel containing a deep active-site groove, consistent with its 'endo' mode of action. The two essential catalytic carboxylic residues (Glu159 and Glu265) are located at the active site within 5.5 A of each other, as expected for 'retaining' glycoside hydrolases. A unique subdomain was identified in the carboxy-terminal part of the enzyme and was suggested to have a role in xylan binding. The three-dimensional structure of XT6 is of great interest since it provides a favourable starting point for the rational improvement of its already high thermal and pH stabilities, which are required for a number of biotechnological and industrial applications.

  12. Ectodermal Influx and Cell Hypertrophy Provide Early Growth for All Murine Mammary Rudiments, and Are Differentially Regulated among Them by Gli3

    PubMed Central

    Lee, May Yin; Racine, Victor; Jagadpramana, Peter; Sun, Li; Yu, Weimiao; Du, Tiehua; Spencer-Dene, Bradley; Rubin, Nicole; Le, Lendy; Ndiaye, Delphine; Bellusci, Saverio; Kratochwil, Klaus; Veltmaat, Jacqueline M.

    2011-01-01

    Mammary gland development starts in utero with one or several pairs of mammary rudiments (MRs) budding from the surface ectodermal component of the mammalian embryonic skin. Mice develop five pairs, numbered MR1 to MR5 from pectoral to inguinal position. We have previously shown that Gli3Xt-J/Xt-J mutant embryos, which lack the transcription factor Gli3, do not form MR3 and MR5. We show here that two days after the MRs emerge, Gli3Xt-J/Xt-J MR1 is 20% smaller, and Gli3Xt-J/Xt-J MR2 and MR4 are 50% smaller than their wild type (wt) counterparts. Moreover, while wt MRs sink into the underlying dermis, Gli3Xt-J/Xt-J MR4 and MR2 protrude outwardly, to different extents. To understand why each of these five pairs of functionally identical organs has its own, distinct response to the absence of Gli3, we determined which cellular mechanisms regulate growth of the individual MRs, and whether and how Gli3 regulates these mechanisms. We found a 5.5 to 10.7-fold lower cell proliferation rate in wt MRs compared to their adjacent surface ectoderm, indicating that MRs do not emerge or grow via locally enhanced cell proliferation. Cell-tracing experiments showed that surface ectodermal cells are recruited toward the positions where MRs emerge, and contribute to MR growth during at least two days. During the second day of MR development, peripheral cells within the MRs undergo hypertrophy, which also contributes to MR growth. Limited apoptotic cell death counterbalances MR growth. The relative contribution of each of these processes varies among the five MRs. Furthermore, each of these processes is impaired in the absence of Gli3, but to different extents in each MR. This differential involvement of Gli3 explains the variation in phenotype among Gli3Xt-J/Xt-J MRs, and may help to understand the variation in numbers and positions of mammary glands among mammals. PMID:22046263

  13. Optic Nerve Sheath Tethering in Adduction Occurs in Esotropia and Hypertropia, But Not in Exotropia

    PubMed Central

    Suh, Soh Youn; Clark, Robert A.; Demer, Joseph L.

    2018-01-01

    Purpose Repetitive strain to the optic nerve (ON) due to tethering in adduction has been recently proposed as an intraocular pressure-independent mechanism of optic neuropathy in primary open-angle glaucoma. Since strabismus may alter adduction, we investigated whether gaze-related ON straightening and associated globe translation differ in horizontal and vertical strabismus. Methods High-resolution orbital magnetic resonance imaging was obtained in 2-mm thick quasi-coronal planes using surface coils in 25 subjects (49 orbits) with esotropia (ET, 19 ± 3.6Δ SEM), 11 (15 orbits) with exotropia (XT, 33.7 ± 7.3Δ), 7 (12 orbits) with hypertropia (HT, 14.6 ± 3.2Δ), and 31 normal controls (62 orbits) in target-controlled central gaze, and in maximum attainable abduction and adduction. Area centroids were used to determine ON path sinuosity and globe positions. Results Adduction angles achieved in ET (30.6° ± 0.9°) and HT (27.2° ± 2.3°) did not significantly differ from normal (28.3° ± 0.7°), but significantly less adduction was achieved in XT (19.0° ± 2.5°, P = 0.005). ON sheath tethering in adduction occurred in ET and HT similarly to normal, but did not in XT. The globe translated significantly less than normal, nasally in adduction in XT and temporally in abduction in ET and HT (P < 0.02, for all). Globe retraction did not occur during abduction or adduction in any group. Conclusions Similar to normal subjects, the ON and sheath become tethered without globe retraction in ET and HT. In XT, adduction tethering does not occur, possibly due to limited adduction angle. Thus, therapeutic limitation of adduction could be considered as a possible treatment for ON sheath tethering.

  14. Global Precipitation Estimates from Cross-Track Passive Microwave Observations Using a Physically-Based Retrieval Scheme

    NASA Technical Reports Server (NTRS)

    Kidd, Chris; Matsui, Toshi; Chern, Jiundar; Mohr, Karen; Kummerow, Christian; Randel, Dave

    2015-01-01

    The estimation of precipitation across the globe from satellite sensors provides a key resource in the observation and understanding of our climate system. Estimates from all pertinent satellite observations are critical in providing the necessary temporal sampling. However, consistency in these estimates from instruments with different frequencies and resolutions is critical. This paper details the physically based retrieval scheme to estimate precipitation from cross-track (XT) passive microwave (PM) sensors on board the constellation satellites of the Global Precipitation Measurement (GPM) mission. Here the Goddard profiling algorithm (GPROF), a physically based Bayesian scheme developed for conically scanning (CS) sensors, is adapted for use with XT PM sensors. The present XT GPROF scheme utilizes a model-generated database to overcome issues encountered with an observational database as used by the CS scheme. The model database ensures greater consistency across meteorological regimes and surface types by providing a more comprehensive set of precipitation profiles. The database is corrected for bias against the CS database to ensure consistency in the final product. Statistical comparisons over western Europe and the United States show that the XT GPROF estimates are comparable with those from the CS scheme. Indeed, the XT estimates have higher correlations against surface radar data, while maintaining similar root-mean-square errors. Latitudinal profiles of precipitation show the XT estimates are generally comparable with the CS estimates, although in the southern midlatitudes the peak precipitation is shifted equatorward while over the Arctic large differences are seen between the XT and the CS retrievals.

  15. Comparative evaluation of microleakage of lingual retainer wires bonded with three different lingual retainer composites: an in vitro study.

    PubMed

    Nimbalkar-Patil, Smita; Vaz, Anna; Patil, Pravinkumar G

    2014-11-01

    To evaluate microleakage when two types of retainer wires were bonded with two light cured and a self cured lingual retainer composites. Total 120 freshly extracted human mandibular incisor teeth were collected and separated into six subgroups of 20 teeth each. Two different wires, a 0.036 inch hard round stainless steel (HRSS) wire sandblasted at the ends and 0.0175 inch multistranded wire bonded onto the lingual surfaces of the incisors with three different types of composite resins of 3M company; Concise Orthodontic (self-cure), Transbond XT (light-cure) and Transbond LR (light-cure). Specimens were further sealed with a nail varnish, stained with 0.5% basic fuchsine for 24 hours, sectioned and examined under a stereomicroscope, and scored for microleakage for the enamel-composite and wire-composite interfaces. Statistical analysis was performed by Kruskal-Wallis and Mann-Whitney U-tests. For HRSS wire, at the enamel-composite interface, the microleakage was least with Transbond LR followed by Concise Orthodontic and greatest for Transbond XT (p<0.05). At the wire composite interface too, the microleakage was in order of Transbond LR

  16. Comparison of acute elastic recoil between the SAPIEN-XT and SAPIEN valves in transfemoral-transcatheter aortic valve replacement.

    PubMed

    Garg, Aatish; Parashar, Akhil; Agarwal, Shikhar; Aksoy, Olcay; Hammadah, Muhammad; Poddar, Kanhaiya Lal; Puri, Rishi; Svensson, Lars G; Krishnaswamy, Amar; Tuzcu, E Murat; Kapadia, Samir R

    2015-02-15

    The SAPIEN-XT is a newer generation balloon-expandable valve created of cobalt chromium frame, as opposed to the stainless steel frame used in the older generation SAPIEN valve. We sought to determine if there was difference in acute recoil between the two valves. All patients who underwent transfemoral-transcatheter aortic valve replacement using the SAPIEN-XT valve at the Cleveland Clinic were included. Recoil was measured using biplane cine-angiographic image analysis of valve deployment. Acute recoil was defined as [(valve diameter at maximal balloon inflation) - (valve diameter after deflation)]/valve diameter at maximal balloon inflation (reported as percentage). Patients undergoing SAPIEN valve implantation were used as the comparison group. Among the 23 mm valves, the mean (standard deviation-SD) acute recoil was 2.77% (1.14) for the SAPIEN valve as compared to 3.75% (1.52) for the SAPIEN XT valve (P = 0.04). Among the 26 mm valves, the mean (SD) acute recoil was 2.85% (1.4) for the SAPIEN valve as compared to 4.32% (1.63) for the SAPIEN XT valve (P = 0.01). Multivariable linear regression analysis demonstrated significantly greater adjusted recoil in the SAPIEN XT valves as compared to the SAPIEN valves by 1.43% [(95% CI: 0.69-2.17), P < 0.001]. However, the residual peak gradient was less for SAPIEN XT compared to SAPIEN valves [18.86 mm Hg versus 23.53 mm Hg (P = 0.01)]. Additionally, no difference in paravalvular leak was noted between the two valve types (P = 0.78). The SAPIEN XT valves had significantly greater acute recoil after deployment compared to the SAPIEN valves. Implications of this difference in acute recoil on valve performance need to be investigated in future studies. © 2014 Wiley Periodicals, Inc.

  17. In-orbit results of Delfi-n3Xt: Lessons learned and move forward

    NASA Astrophysics Data System (ADS)

    Guo, Jian; Bouwmeester, Jasper; Gill, Eberhard

    2016-04-01

    This paper provides an update of the Delfi nanosatellite programme of the Delft University of Technology (TU Delft), with a focus on the recent in-orbit results of the second TU Delft satellite Delfi-n3Xt. In addition to the educational objective that has been reached with more than 80 students involved in the project, most of the technological objectives of Delfi-n3Xt have also been fulfilled with successful in-orbit demonstrations of payloads and platform. Among these demonstrations, four are highlighted in this paper, including a solid cool gas micropropulsion system, a new type of solar cell, a more robust Command and Data Handling Subsystem (CDHS), and a highly integrated Attitude Determination and Control Subsystem (ADCS) that performs three-axis active control using reaction wheels. Through the development of Delfi-n3Xt, significant experiences and lessons have been learned, which motivated a further step towards DelFFi, the third Delfi CubeSat mission, to demonstrate autonomous formation flying using two CubeSats named Delta and Phi. A brief update of the DelFFi mission is also provided.

  18. Soft x-ray imager (SXI) onboard the NeXT satellite

    NASA Astrophysics Data System (ADS)

    Tsuru, Takeshi Go; Takagi, Shin-Ichiro; Matsumoto, Hironori; Inui, Tatsuya; Ozawa, Midori; Koyama, Katsuji; Tsunemi, Hiroshi; Hayashida, Kiyoshi; Miyata, Emi; Ozawa, Hideki; Touhiguchi, Masakuni; Matsuura, Daisuke; Dotani, Tadayasu; Ozaki, Masanobu; Murakami, Hiroshi; Kohmura, Takayoshi; Kitamoto, Shunji; Awaki, Hisamitsu

    2006-06-01

    We give overview and the current status of the development of the Soft X-ray Imager (SXI) onboard the NeXT satellite. SXI is an X-ray CCD camera placed at the focal plane detector of the Soft X-ray Telescopes for Imaging (SXT-I) onboard NeXT. The pixel size and the format of the CCD is 24 x 24μm (IA) and 2048 x 2048 x 2 (IA+FS). Currently, we have been developing two types of CCD as candidates for SXI, in parallel. The one is front illumination type CCD with moderate thickness of the depletion layer (70 ~ 100μm) as a baseline plan. The other one is the goal plan, in which we develop back illumination type CCD with a thick depletion layer (200 ~ 300μm). For the baseline plan, we successfully developed the proto model 'CCD-NeXT1' with the pixel size of 12μm x 12μm and the CCD size of 24mm x 48mm. The depletion layer of the CCD has reached 75 ~ 85μm. The goal plan is realized by introduction of a new type of CCD 'P-channel CCD', which collects holes in stead of electrons in the common 'N-channel CCD'. By processing a test model of P-channel CCD we have confirmed high quantum efficiency above 10 keV with an equivalent depletion layer of 300μm. A back illumination type of P-channel CCD with a depletion layer of 200μm with aluminum coating for optical blocking has been also successfully developed. We have been also developing a thermo-electric cooler (TEC) with the function of the mechanically support of the CCD wafer without standoff insulators, for the purpose of the reduction of thermal input to the CCD through the standoff insulators. We have been considering the sensor housing and the onboard electronics for the CCD clocking, readout and digital processing of the frame date.

  19. Evaluation of shear bond strength of orthodontic brackets bonded with nano-filled composites.

    PubMed

    Chalipa, Javad; Akhondi, Mohammad Sadegh Ahmad; Arab, Sepideh; Kharrazifard, Mohammad Javad; Ahmadyar, Maryam

    2013-09-01

    The purpose of this study was to evaluate the shear bond strength (SBS) of orthodontic brackets bonded with two types of nano-composites in comparison to a conventional orthodontic composite. Sixty extracted human first premolars were randomly divided into 3 groups each containing 20 teeth. In group I, a conventional orthodontic composite (Transbond XT) was used to bond the brackets, while two nano-composites (Filtek TM Supreme XT and AELITE Aesthetic Enamel) were used in groups II and III respectively. The teeth were stored in distilled water at 37°C for 24 hours, thermocycled in distilled water and debonded with a universal testing machine at a crosshead speed of 1 mm/min. The adhesive remnant index (ARI) was also evaluated using a stereomicroscope. AELITE Aesthetic Enamel nano-composite revealed a SBS value of 8.44±2.09 MPa, which was higher than Transbond XT (6.91±2.13) and Filtek TM Supreme XT (6.04±2.01). Statistical analysis revealed a significant difference between groups II and III (P < 0.05). No significant difference was found between groups I and III, and between groups I and II (P > 0.05). Evaluation of ARI showed that Transbond XT left fewer adhesive remains on teeth after debonding. Results of this study indicate that the aforementioned nano-composites can be successfully used for bonding orthodontic brackets.

  20. Evaluation of Shear Bond Strength of Orthodontic Brackets Bonded with Nano-Filled Composites

    PubMed Central

    Chalipa, Javad; Akhondi, Mohammad Sadegh Ahmad; Arab, Sepideh; Kharrazifard, Mohammad Javad; Ahmadyar, Maryam

    2013-01-01

    Objectives: The purpose of this study was to evaluate the shear bond strength (SBS) of orthodontic brackets bonded with two types of nano-composites in comparison to a conventional orthodontic composite. Materials and Methods: Sixty extracted human first premolars were randomly divided into 3 groups each containing 20 teeth. In group I, a conventional orthodontic composite (Transbond XT) was used to bond the brackets, while two nano-composites (Filtek TM Supreme XT and AELITE Aesthetic Enamel) were used in groups II and III respectively. The teeth were stored in distilled water at 37°C for 24 hours, thermocycled in distilled water and debonded with a universal testing machine at a crosshead speed of 1 mm/min. The adhesive remnant index (ARI) was also evaluated using a stereomicroscope. Results: AELITE Aesthetic Enamel nano-composite revealed a SBS value of 8.44±2.09 MPa, which was higher than Transbond XT (6.91±2.13) and Filtek TM Supreme XT (6.04±2.01). Statistical analysis revealed a significant difference between groups II and III (P < 0.05). No significant difference was found between groups I and III, and between groups I and II (P > 0.05). Evaluation of ARI showed that Transbond XT left fewer adhesive remains on teeth after debonding. Conclusion: Results of this study indicate that the aforementioned nano-composites can be successfully used for bonding orthodontic brackets. PMID:24910655

  1. neXtA5: accelerating annotation of articles via automated approaches in neXtProt.

    PubMed

    Mottin, Luc; Gobeill, Julien; Pasche, Emilie; Michel, Pierre-André; Cusin, Isabelle; Gaudet, Pascale; Ruch, Patrick

    2016-01-01

    The rapid increase in the number of published articles poses a challenge for curated databases to remain up-to-date. To help the scientific community and database curators deal with this issue, we have developed an application, neXtA5, which prioritizes the literature for specific curation requirements. Our system, neXtA5, is a curation service composed of three main elements. The first component is a named-entity recognition module, which annotates MEDLINE over some predefined axes. This report focuses on three axes: Diseases, the Molecular Function and Biological Process sub-ontologies of the Gene Ontology (GO). The automatic annotations are then stored in a local database, BioMed, for each annotation axis. Additional entities such as species and chemical compounds are also identified. The second component is an existing search engine, which retrieves the most relevant MEDLINE records for any given query. The third component uses the content of BioMed to generate an axis-specific ranking, which takes into account the density of named-entities as stored in the Biomed database. The two ranked lists are ultimately merged using a linear combination, which has been specifically tuned to support the annotation of each axis. The fine-tuning of the coefficients is formally reported for each axis-driven search. Compared with PubMed, which is the system used by most curators, the improvement is the following: +231% for Diseases, +236% for Molecular Functions and +3153% for Biological Process when measuring the precision of the top-returned PMID (P0 or mean reciprocal rank). The current search methods significantly improve the search effectiveness of curators for three important curation axes. Further experiments are being performed to extend the curation types, in particular protein-protein interactions, which require specific relationship extraction capabilities. In parallel, user-friendly interfaces powered with a set of JSON web services are currently being implemented into the neXtProt annotation pipeline.Available on: http://babar.unige.ch:8082/neXtA5Database URL: http://babar.unige.ch:8082/neXtA5/fetcher.jsp. © The Author(s) 2016. Published by Oxford University Press.

  2. neXtA5: accelerating annotation of articles via automated approaches in neXtProt

    PubMed Central

    Mottin, Luc; Gobeill, Julien; Pasche, Emilie; Michel, Pierre-André; Cusin, Isabelle; Gaudet, Pascale; Ruch, Patrick

    2016-01-01

    The rapid increase in the number of published articles poses a challenge for curated databases to remain up-to-date. To help the scientific community and database curators deal with this issue, we have developed an application, neXtA5, which prioritizes the literature for specific curation requirements. Our system, neXtA5, is a curation service composed of three main elements. The first component is a named-entity recognition module, which annotates MEDLINE over some predefined axes. This report focuses on three axes: Diseases, the Molecular Function and Biological Process sub-ontologies of the Gene Ontology (GO). The automatic annotations are then stored in a local database, BioMed, for each annotation axis. Additional entities such as species and chemical compounds are also identified. The second component is an existing search engine, which retrieves the most relevant MEDLINE records for any given query. The third component uses the content of BioMed to generate an axis-specific ranking, which takes into account the density of named-entities as stored in the Biomed database. The two ranked lists are ultimately merged using a linear combination, which has been specifically tuned to support the annotation of each axis. The fine-tuning of the coefficients is formally reported for each axis-driven search. Compared with PubMed, which is the system used by most curators, the improvement is the following: +231% for Diseases, +236% for Molecular Functions and +3153% for Biological Process when measuring the precision of the top-returned PMID (P0 or mean reciprocal rank). The current search methods significantly improve the search effectiveness of curators for three important curation axes. Further experiments are being performed to extend the curation types, in particular protein–protein interactions, which require specific relationship extraction capabilities. In parallel, user-friendly interfaces powered with a set of JSON web services are currently being implemented into the neXtProt annotation pipeline. Available on: http://babar.unige.ch:8082/neXtA5 Database URL: http://babar.unige.ch:8082/neXtA5/fetcher.jsp PMID:27374119

  3. A performance evaluation of the IBM 370/XT personal computer

    NASA Technical Reports Server (NTRS)

    Dominick, Wayne D. (Editor); Triantafyllopoulos, Spiros

    1984-01-01

    An evaluation of the IBM 370/XT personal computer is given. This evaluation focuses primarily on the use of the 370/XT for scientific and technical applications and applications development. A measurement of the capabilities of the 370/XT was performed by means of test programs which are presented. Also included is a review of facilities provided by the operating system (VM/PC), along with comments on the IBM 370/XT hardware configuration.

  4. Effects of different etching methods and bonding procedures on shear bond strength of orthodontic metal brackets applied to different CAD/CAM ceramic materials.

    PubMed

    Buyuk, S Kutalmış; Kucukekenci, Ahmet Serkan

    2018-03-01

    To investigate the shear bond strength (SBS) of orthodontic metal brackets applied to different types of ceramic surfaces treated with different etching procedures and bonding agents. Monolithic CAD/CAM ceramic specimens (N = 120; n = 40 each group) of feldspathic ceramic Vita Mark II, resin nanoceramic Lava Ultimate, and hybrid ceramic Vita Enamic were fabricated (14 × 12 × 3 mm). Ceramic specimens were separated into four subgroups (n = 10) according to type of surface treatment and bonding onto the ceramic surface. Within each group, four subgroups were prepared by phosphoric acid, hydrofluoric acid, Transbond XT primer, and Clearfill Ceramic primer. Mandibular central incisor metal brackets were bonded with light-cure composite. The SBS data were analyzed using three-way analysis of variance (ANOVA) and Tukey HSD tests. The highest SBS was found in the Vita Enamic group, which is a hybrid ceramic, etched with hydrofluoric acid and applied Transbond XT Adhesive primer (7.28 ± 2.49 MPa). The lowest SBS was found in the Lava Ultimate group, which is a resin nano-ceramic etched with hydrofluoric acid and applied Clearfill ceramic primer (2.20 ± 1.21 MPa). CAD/CAM material types and bonding procedures affected bond strength ( P < .05), but the etching procedure did not ( P > .05). The use of Transbond XT as a primer bonding agent resulted in higher SBS.

  5. Streptococcus mutans forms xylitol-resistant biofilm on excess adhesive flash in novel ex-vivo orthodontic bracket model.

    PubMed

    Ho, Cindy S F; Ming, Yue; Foong, Kelvin W C; Rosa, Vinicius; Thuyen, Truong; Seneviratne, Chaminda J

    2017-04-01

    During orthodontic bonding procedures, excess adhesive is invariably left on the tooth surface at the interface between the bracket and the enamel junction; it is called excess adhesive flash (EAF). We comparatively evaluated the biofilm formation of Streptococcus mutans on EAF produced by 2 adhesives and examined the therapeutic efficacy of xylitol on S mutans formed on EAF. First, we investigated the biofilm formation of S mutans on 3 orthodontic bracket types: stainless steel preadjusted edgewise, ceramic preadjusted edgewise, and stainless steel self-ligating. Subsequently, tooth-colored Transbond XT (3M Unitek, Monrovia, Calif) and green Grengloo (Ormco, Glendora, Calif) adhesives were used for bonding ceramic brackets to extracted teeth. S mutans biofilms on EAF produced by the adhesives were studied using the crystal violet assay and scanning electron microscopy. Surface roughness and surface energy of the EAF were examined. The therapeutic efficacies of different concentrations of xylitol were tested on S mutans biofilms. Significantly higher biofilms were formed on the ceramic preadjusted edgewise brackets (P = 0.003). Transbond XT had significantly higher S mutans biofilms compared with Grengloo surfaces (P = 0.007). There was no significant difference in surface roughness between Transbond XT and Grengloo surfaces (P >0.05). Surface energy of Transbond XT had a considerably smaller contact angle than did Grengloo, suggesting that Transbond XT is a more hydrophilic material. Xylitol at low concentrations had no significant effect on the reduction of S mutans biofilms on orthodontic adhesives (P = 0.016). Transbond XT orthodontic adhesive resulted in more S mutans biofilm compared with Grengloo adhesive on ceramic brackets. Surface energy seemed to play a more important role than surface roughness for the formation of S mutans biofilm on EAF. Xylitol does not appear to have a therapeutic effect on mature S mutans biofilm. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  6. Molecular Cloning and Functional Characterization of Xenopus tropicalis Frog Transient Receptor Potential Vanilloid 1 Reveal Its Functional Evolution for Heat, Acid, and Capsaicin Sensitivities in Terrestrial Vertebrates*

    PubMed Central

    Ohkita, Masashi; Saito, Shigeru; Imagawa, Toshiaki; Takahashi, Kenji; Tominaga, Makoto; Ohta, Toshio

    2012-01-01

    The functional difference of thermosensitive transient receptor potential (TRP) channels in the evolutionary context has attracted attention, but thus far little information is available on the TRP vanilloid 1 (TRPV1) function of amphibians, which diverged earliest from terrestrial vertebrate lineages. In this study we cloned Xenopus tropicalis frog TRPV1 (xtTRPV1), and functional characterization was performed using HeLa cells heterologously expressing xtTRPV1 (xtTRPV1-HeLa) and dorsal root ganglion neurons isolated from X. tropicalis (xtDRG neurons) by measuring changes in the intracellular calcium concentration ([Ca2+]i). The channel activity was also observed in xtTRPV1-expressing Xenopus oocytes. Furthermore, we tested capsaicin- and heat-induced nocifensive behaviors of the frog X. tropicalis in vivo. At the amino acid level, xtTRPV1 displays ∼60% sequence identity to other terrestrial vertebrate TRPV1 orthologues. Capsaicin induced [Ca2+]i increases in xtTRPV1-HeLa and xtDRG neurons and evoked nocifensive behavior in X. tropicalis. However, its sensitivity was extremely low compared with mammalian orthologues. Low extracellular pH and heat activated xtTRPV1-HeLa and xtDRG neurons. Heat also evoked nocifensive behavior. In oocytes expressing xtTRPV1, inward currents were elicited by heat and low extracellular pH. Mutagenesis analysis revealed that two amino acids (tyrosine 523 and alanine 561) were responsible for the low sensitivity to capsaicin. Taken together, our results indicate that xtTRPV1 functions as a polymodal receptor similar to its mammalian orthologues. The present study demonstrates that TRPV1 functions as a heat- and acid-sensitive channel in the ancestor of terrestrial vertebrates. Because it is possible to examine vanilloid and heat sensitivities in vitro and in vivo, X. tropicalis could be the ideal experimental lower vertebrate animal for the study of TRPV1 function. PMID:22130664

  7. Effect of a low-viscosity adhesive resin on the adhesion of metal brackets to enamel etched with hydrochloric or phosphoric acid combined with conventional adhesives.

    PubMed

    Yetkiner, Enver; Ozcan, Mutlu; Wegehaupt, Florian Just; Wiegand, Annette; Eden, Ece; Attin, Thomas

    2013-12-01

    This study investigated the effect of a low-viscosity adhesive resin (Icon) applied after either hydrochloric (HCl) or phosphoric acid (H3PO4) on the adhesion of metal brackets to enamel. Failure types were analyzed. The crowns of bovine incisors (N = 20) were sectioned mesio-distally and inciso-gingivally, then randomly assigned to 4 groups according to the following protocols to receive mandibular incisor brackets: 1) H3PO4 (37%)+TransbondXT (3M UNITEK); 2) H3PO4 (37%)+Icon+TransbondXT; 3) HCl (15%)+Icon (DMG)+TransbondXT 4) HCl (15%)+Icon+Heliobond (Ivoclar Vivadent)+TransbondXT. Specimens were stored in distilled water at 37°C for 24 h and thermocycled (5000x, 5°C to 55°C). The shear bond strength (SBS) test was performed using a universal testing machine (1 mm/min). Failure types were classified according to the Adhesive Remnant Index (ARI). Contact angles of adhesive resins were measured (n = 5 per adhesive) on ceramic surfaces. No significant difference in SBS was observed, implying no difference between combinations of adhesive resins and etching agents (p = 0.712; ANOVA). The Weibull distribution presented significantly lower Weibull modulus (m) of group 3 (m = 2.97) compared to other groups (m = 5.2 to 6.6) (p < 0.05). The mean SBS results (MPa) in descending order were as follows: group 4 (46.7 ± 10.3) > group 1 (45.4 ± 7.9) > group 2 (44.2 ± 10.6) > group 3 (42.6 ± 15.5). While in groups 1, 3, and 4 exclusively an ARI score of 0 (no adhesive left on tooth) was observed, in group 2, only one specimen demonstrated score 1 (less than half of adhesive left on tooth). Contact angle measurements were as follows: Icon (25.86 ± 3.81 degrees), Heliobond (31.98 ± 3.17 degrees), TransbondXT (35 ± 2.21 degrees). Icon can be safely used with the conventional adhesives tested on surfaces etched with either HCl or H3PO4.

  8. Autosomal dominant frontonasal dysplasia (atypical Greig syndrome): Lessons from the Xt mutant mouse

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cunningham, M.L.; Nunes, M.E.

    1994-09-01

    Greig syndrome is the autosomal dominant association of mild hypertelorism, variable polysyndactyly, and normal intelligence. Several families have been found to have translocations or deletions of 7p13 interrupting the normal expression of GLI3 (a zinc finger, DNA binding, transcription repressor). Recently, a mutation in the mouse homologue of GLI3 was found in the extra-toes mutant mouse (Xt). The phenotypic features of this mouse model include mild hypertelorism, postaxial polydactyly of the forelimbs, preaxial polydactyly of the hindlimbs, and variable tibial hemimelia. The homozygous mutant Xt/Xt have severe frontonasal dysplasia (FND), polysyndactyly of fore-and hindlimbs and invariable tibial hemimelia. We havemore » recently evaluated a child with severe (type D) frontonasal dysplasia, fifth finger camptodactyly, preaxial polydactyly of one foot, and ispilateral tibial hemimelia. His father was born with a bifid nose, broad columnella, broad feet, and a two centimeter leg length discrepancy. The paternal grandmother of the proband is phenotypically normal; however, her fraternal twin died at birth with severe facial anomalies. The paternal great-grandmother of the proband is phenotypically normal however her niece was born with moderate ocular hypertelorism. This pedigree is suggestive of an autosomal dominant form of frontonasal dysplasia with variable expressivity. The phenotypic features of our case more closely resemble the Xt mouse than the previously defined features of Greig syndrome in humans. This suggests that a mutation in GLI3 may be responsible for FND in this family. We are currently using polymorphic dinucleotide repeat markers flanking GLI3 in a attempt to demonstrate linkage in this pedigree. Demonstration of a GLI3 mutation in this family would broaden our view of the spectrum of phenotypes possible in Greig syndrome and could provide insight into genotype/phenotype correlation in FND.« less

  9. An overview of the Progenika ID CORE XT: an automated genotyping platform based on a fluidic microarray system.

    PubMed

    Goldman, Mindy; Núria, Núria; Castilho, Lilian M

    2015-01-01

    Automated testing platforms facilitate the introduction of red cell genotyping of patients and blood donors. Fluidic microarray systems, such as Luminex XMAP (Austin, TX), are used in many clinical applications, including HLA and HPA typing. The Progenika ID CORE XT (Progenika Biopharma-Grifols, Bizkaia, Spain) uses this platform to analyze 29 polymorphisms determining 37 antigens in 10 blood group systems. Once DNA has been extracted, processing time is approximately 4 hours. The system is highly automated and includes integrated analysis software that produces a file and a report with genotype and predicted phenotype results.

  10. Physical Habitat Characteristics on the North and South Forks of the Shenandoah River, VA in 2002-2007

    USGS Publications Warehouse

    Krstolic, Jennifer L.; Hayes, Donald C.

    2010-01-01

    Data collected with the GeoXT Trimble GPS unit using ArcPad 6.1. (summer 2006-2007). Files were created within a geodatabase to create a data dictionary for use in ArcPad during data collection. Drop down lists for habitat type, substrate, depth, width, length, and descriptions were included. Data files produced on the GeoXT were point shapefiles that could be checked back into the geodatabase and viewable as a layer. Points were gathered while canoeing along the South Fork Shenandoah River. Each location marked a change in meso-scale habitat type. GPS points were supplemented with GIS-derived points in areas where manual measurements were made. The points were used to generate a line coverage. This coverage represents physical habitat at a meso-scale (width of stream).

  11. Complex trajectories in a classical periodic potential

    NASA Astrophysics Data System (ADS)

    Anderson, Alexander G.; Bender, Carl M.

    2012-11-01

    This paper examines the complex trajectories of a classical particle in the potential V(x) = -cos (x). Almost all the trajectories describe a particle that hops from one well to another in an erratic fashion. However, it is shown analytically that there are two special classes of trajectories x(t) determined only by the energy of the particle and not by the initial position of the particle. The first class consists of periodic trajectories; that is, trajectories that return to their initial position x(0) after some real time T. The second class consists of trajectories for which there exists a real time T such that x(t + T) = x(t) ± 2π. These two classes of classical trajectories are analogous to valence and conduction bands in quantum mechanics, where the quantum particle either remains localized or else tunnels resonantly (conducts) through a crystal lattice. These two special types of trajectories are associated with sets of energies of measure 0. For other energies, it is shown that for long times the average velocity of the particle becomes a fractal-like function of energy.

  12. Development of potent anti-infective agents from Silurana tropicalis: conformational analysis of the amphipathic, alpha-helical antimicrobial peptide XT-7 and its non-haemolytic analogue [G4K]XT-7.

    PubMed

    Subasinghage, Anusha P; Conlon, J Michael; Hewage, Chandralal M

    2010-04-01

    Peptide XT-7 (GLLGP(5)LLKIA(10)AKVGS(15)NLL.NH(2)) is a cationic, leucine-rich peptide, first isolated from skin secretions of the frog, Silurana tropicalis (Pipidae). The peptide shows potent, broad-spectrum antimicrobial activity but its therapeutic potential is limited by haemolytic activity (LC(50)=140 microM). The analogue [G4K]XT-7, however, retains potent antimicrobial activity but is non-haemolytic (LC(50)>500 microM). In order to elucidate the molecular basis for this difference in properties, the three dimensional structures of XT-7 and the analogue have been investigated by proton NMR spectroscopy and molecular modelling. In aqueous solution, both peptides lack secondary structure. In a 2,2,2-trifluoroethanol (TFE-d(3))-H(2)O mixed solvent system, XT-7 is characterised by a right handed alpha-helical conformation between residues Leu(3) and Leu(17) whereas [G4K]XT-7 adopts a more restricted alpha-helical conformation between residues Leu(6) and Leu(17). A similar conformation for XT-7 in 1,2-dihexanoyl-sn-glycero-3-phosphocholine (DHPC) micellular media was observed with a helical segment between Leu(3) and Leu(17). However, differences in side chain orientations restricting the hydrophilic residues to a smaller patch resulted in an increased hydrophobic surface relative to the conformation in TFE-H(2)O. Molecular modelling of the structures obtained in our study demonstrates the amphipathic character of the helical segments. It is proposed that the marked decrease in haemolytic activity produced by the substitution Gly(4)-->Lys in XT-7 arises from a decrease in both helicity and hydrophobicity. These studies may facilitate the development of potent but non-toxic anti-infective agents based upon the structure of XT-7. Copyright 2009 Elsevier B.V. All rights reserved.

  13. First results of cirrus clouds properties by means of a pollyxt raman lidar at two measurement sites

    NASA Astrophysics Data System (ADS)

    Voudouri, Kalliopi-Artemis; Giannakaki, Elina; Komppula, Mika; Balis, Dimitris

    2018-04-01

    Geometrical and optical characteristics of cirrus clouds using Raman lidar PollyXT measurements at different locations are presented. The PollyXT has been participated in two long-term experimental campaigns, one close to New Delhi in India and one at Elandsfontein in South Africa, providing continuous measurements and covering a wide range of cloud types. First results of cirrus cloud properties at different latitudes, as well as their temporal distributions are presented in this study. An automatic cirrus clouds detection algorithm is applied based on the wavelet covariance transform. The measurements at New Delhi performed from March 2008 to February 2009, while at Elandsfontein measurements were performed from December 2009 to January 2011.

  14. Chromosome Banding in Amphibia. XXXVI. Multimorphic Sex Chromosomes and an Enigmatic Sex Determination in Eleutherodactylus johnstonei (Anura, Eleutherodactylidae).

    PubMed

    Schmid, Michael; Steinlein, Claus

    2018-01-01

    A detailed cytogenetic study on the leaf litter frog Eleutherodactylus johnstonei from 14 different Caribbean islands and the mainlands of Venezuela and Guyana revealed the existence of multimorphic XY♂/XX♀ sex chromosomes 14. Their male sex determination and development depends either on the presence of 2 telocentric chromosomes 14 (XtYt), or on 1 submetacentric chromosome 14 (Xsm) plus 1 telocentric chromosome 14 (Yt), or on the presence of 2 submetacentric chromosomes 14 (XsmYsm). The female sex determination and development requires either the presence of 2 telocentric chromosomes 14 (XtXt) or 2 submetacentric chromosomes 14 (XsmXsm). In all individuals analyzed, the sex chromosomes 14 carry a prominent nucleolus organizer region in their long arms. An explanation is given for the origin of the (XtYt)♂, (XsmYt)♂, (XsmYsm)♂, (XtXt)♀, and (XsmXsm)♀ in the different populations of E. johnstonei. Furthermore, the present study gives detailed data on the chromosome banding patterns, in situ hybridization experiments, and the genome size of E. johnstonei. © 2018 S. Karger AG, Basel.

  15. Documentation for the “XT3D” option in the Node Property Flow (NPF) Package of MODFLOW 6

    USGS Publications Warehouse

    Provost, Alden M.; Langevin, Christian D.; Hughes, Joseph D.

    2017-08-10

    This report describes the “XT3D” option in the Node Property Flow (NPF) Package of MODFLOW 6. The XT3D option extends the capabilities of MODFLOW by enabling simulation of fully three-dimensional anisotropy on regular or irregular grids in a way that properly takes into account the full, three-dimensional conductivity tensor. It can also improve the accuracy of groundwater-flow simulations in cases in which the model grid violates certain geometric requirements. Three example problems demonstrate the use of the XT3D option to simulate groundwater flow on irregular grids and through three-dimensional porous media with anisotropic hydraulic conductivity.Conceptually, the XT3D method of estimating flow between two MODFLOW 6 model cells can be viewed in terms of three main mathematical steps: construction of head-gradient estimates by interpolation; construction of fluid-flux estimates by application of the full, three-dimensional form of Darcy’s Law, in which the conductivity tensor can be heterogeneous and anisotropic; and construction of the flow expression by enforcement of continuity of flow across the cell interface. The resulting XT3D flow expression, which relates the flow across the cell interface to the values of heads computed at neighboring nodes, is the sum of terms in which conductance-like coefficients multiply head differences, as in the conductance-based flow expression the NPF Package uses by default. However, the XT3D flow expression contains terms that involve “neighbors of neighbors” of the two cells for which the flow is being calculated. These additional terms have no analog in the conductance-based formulation. When assembled into matrix form, the XT3D formulation results in a larger stencil than the conductance-based formulation; that is, each row of the coefficient matrix generally contains more nonzero elements. The “RHS” suboption can be used to avoid expanding the stencil by placing the additional terms on the right-hand side of the matrix equation and evaluating them at the previous iteration or time step.The XT3D option can be an alternative to the Ghost-Node Correction (GNC) Package. However, the XT3D formulation is typically more computationally intensive than the conductance-based formulation the NPF Package uses by default, either with or without ghost nodes. Before deciding whether to use the GNC Package or XT3D option for production runs, the user should consider whether the conductance-based formulation alone can provide acceptable accuracy for the particular problem being solved.

  16. NeXT Application Development Workshop. [Use and Design of Instructional Applications on the NeXT Computer.

    ERIC Educational Resources Information Center

    Kiel, Don; And Others

    Instructional applications for NeXT computers were developed by nine faculty members from the biology, mathematics and computer science, fine arts, chemistry, physics and astronomy, and geology departments as part of a grant awarded to the California State University at Los Angeles. These notes provide a schedule of events and reports from a 2-day…

  17. Sedative and analgesic effects of intravenous xylazine and tramadol on horses

    PubMed Central

    Seo, Jong-pil; Son, Won-gyun; Gang, Sujin

    2011-01-01

    This study was performed to evaluate the sedative and analgesic effects of xylazine (X) and tramadol (T) intravenously (IV) administered to horses. Six thoroughbred saddle horses each received X (1.0 mg/kg), T (2.0 mg/kg), and a combination of XT (1.0 and 2.0 mg/kg, respectively) IV. Heart rate (HR), respiratory rate (RR), rectal temperature (RT), indirect arterial pressure (IAP), capillary refill time (CRT), sedation, and analgesia (using electrical stimulation and pinprick) were measured before and after drug administration. HR and RR significantly decreased from basal values with X and XT treatments, and significantly increased with T treatment (p < 0.05). RT and IAP also significantly increased with T treatment (p < 0.05). CRT did not change significantly with any treatments. The onset of sedation and analgesia were approximately 5 min after both X and XT treatments; however, the XT combination produced a longer duration of sedation and analgesia than X alone. Two horses in the XT treatment group displayed excited transient behavior within 5 min of drug administration. The results suggest that the XT combination is useful for sedation and analgesia in horses. However, careful monitoring for excited behavior shortly after administration is recommended. PMID:21897102

  18. Advanced and flexible multi-carrier receiver architecture for high-count multi-core fiber based space division multiplexed applications

    PubMed Central

    Asif, Rameez

    2016-01-01

    Space division multiplexing (SDM), incorporating multi-core fibers (MCFs), has been demonstrated for effectively maximizing the data capacity in an impending capacity crunch. To achieve high spectral-density through multi-carrier encoding while simultaneously maintaining transmission reach, benefits from inter-core crosstalk (XT) and non-linear compensation must be utilized. In this report, we propose a proof-of-concept unified receiver architecture that jointly compensates optical Kerr effects, intra- and inter-core XT in MCFs. The architecture is analysed in multi-channel 512 Gbit/s dual-carrier DP-16QAM system over 800 km 19-core MCF to validate the digital compensation of inter-core XT. Through this architecture: (a) we efficiently compensates the inter-core XT improving Q-factor by 4.82 dB and (b) achieve a momentous gain in transmission reach, increasing the maximum achievable distance from 480 km to 1208 km, via analytical analysis. Simulation results confirm that inter-core XT distortions are more relentless for cores fabricated around the central axis of cladding. Predominantly, XT induced Q-penalty can be suppressed to be less than 1 dB up-to −11.56 dB of inter-core XT over 800 km MCF, offering flexibility to fabricate dense core structures with same cladding diameter. Moreover, this report outlines the relationship between core pitch and forward-error correction (FEC). PMID:27270381

  19. Using IMSL Mathematical and Statistical Computer Subroutines in Physiological and Biomechanical Research

    DTIC Science & Technology

    1987-10-01

    NDATA). CSCOEF(4.NDATA). CSVAL. ERROR, F. kFDATA(NDATA). FLOAT, FVAL. RNUNF, SDEV. SMPAR. SQRT. a SYAL . WEIGHT(NDATA), X. XDATA(NDATA). XT INTRINSIC...BREAK.CSCOEF) FYAL - F(XT) ERROR a SVAL - FVAL WRITE (NOUT,’(4F15.4)’) XT. FYAL. SYAL , ERROR 30 CONTINUE C 99999 FORMAT (12X. ’X’. 9X. ’Function’. 7X

  20. Measurements of particle backscatter, extinction, and lidar ratio at 1064 nm with the rotational raman method in Polly-XT

    NASA Astrophysics Data System (ADS)

    Engelmann, Ronny; Haarig, Moritz; Baars, Holger; Ansmann, Albert; Kottas, Michael; Marinou, Eleni

    2018-04-01

    We replaced a 1064-nm interference filter of a Polly-XT lidar system by a 1058-nm filter to observe pure rotational Raman backscattering from atmospheric Nitrogen and Oxygen. Polly-XT is compact Raman lidar with a Nd:YAG laser (20 Hz, 200 mJ at 1064 nm) and a 30-cm telescope mirror which applies photomultipliers in photoncounting mode. We present the first measured signals at 1058 nm and the derived extinction profile from measurements aboard RV Polarstern and in Leipzig. In combination with another Polly-XT system we could also derive particle backscatter and lidar ratio profiles at 1064 nm.

  1. Buckling Modes of Structural Elements of Off-Axis Fiber-Reinforced Plastics

    NASA Astrophysics Data System (ADS)

    Paimushin, V. N.; Polyakova, N. V.; Kholmogorov, S. A.; Shishov, M. A.

    2018-05-01

    The structures of two types of unidirectional fiber-reinforced composites — with an ELUR-P carbon fiber tape, an XT-118 cold-cure binder with an HSE 180 REM prepreg, and a hot-cure binder — were investigated. The diameters of fibers and fiber bundles (threads) of both the types of composites were measured, and their mutual arrangement was examined both in the semifinished products (in the uncured state) and in the finished composites. The defects characteristic of both the types of binder and manufacturing technique were detected in the cured composites. Based on an analysis of the results obtained, linearized problems on the internal multiscale buckling modes of an individual fiber (with and without account of its interaction with the surrounding matrix) or of a fiber bundle are formulated. In the initial atate, these structural elements of the fibrous composites are in a subcritical (unperturbed) state under the action of shear stresses and tension (compression) in the transverse direction. Such an initial stress state is formed in them in tension and compression tests on flat specimens made of off-axis-reinforced composites with straight fibers. To formulate the problems, the equations derived earlier from a consistent variant of geometrically nonlinear equations of elasticity theory by reducing them to the one-dimensional equations of the theory of straight rods on the basis of a refined Timoshenko shear model with account of tensile-compressive strains in the transverse direction are used. It is shown that, in loading test specimens, a continuous rearrangement of composite structure can occur due to the realization and continuous change of internal buckling modes as the wave-formation parameter varies continuously, which apparently explain the decrease revealed in the tangential shear modulus of the fibrous composites with increasing shear strains.

  2. The JPEG XT suite of standards: status and future plans

    NASA Astrophysics Data System (ADS)

    Richter, Thomas; Bruylants, Tim; Schelkens, Peter; Ebrahimi, Touradj

    2015-09-01

    The JPEG standard has known an enormous market adoption. Daily, billions of pictures are created, stored and exchanged in this format. The JPEG committee acknowledges this success and spends continued efforts in maintaining and expanding the standard specifications. JPEG XT is a standardization effort targeting the extension of the JPEG features by enabling support for high dynamic range imaging, lossless and near-lossless coding, and alpha channel coding, while also guaranteeing backward and forward compatibility with the JPEG legacy format. This paper gives an overview of the current status of the JPEG XT standards suite. It discusses the JPEG legacy specification, and details how higher dynamic range support is facilitated both for integer and floating-point color representations. The paper shows how JPEG XT's support for lossless and near-lossless coding of low and high dynamic range images is achieved in combination with backward compatibility to JPEG legacy. In addition, the extensible boxed-based JPEG XT file format on which all following and future extensions of JPEG will be based is introduced. This paper also details how the lossy and lossless representations of alpha channels are supported to allow coding transparency information and arbitrarily shaped images. Finally, we conclude by giving prospects on upcoming JPEG standardization initiative JPEG Privacy & Security, and a number of other possible extensions in JPEG XT.

  3. Computing anticipatory systems with incursion and hyperincursion

    NASA Astrophysics Data System (ADS)

    Dubois, Daniel M.

    1998-07-01

    An anticipatory system is a system which contains a model of itself and/or of its environment in view of computing its present state as a function of the prediction of the model. With the concepts of incursion and hyperincursion, anticipatory discrete systems can be modelled, simulated and controlled. By definition an incursion, an inclusive or implicit recursion, can be written as: x(t+1)=F[…,x(t-1),x(t),x(t+1),…] where the value of a variable x(t+1) at time t+1 is a function of this variable at past, present and future times. This is an extension of recursion. Hyperincursion is an incursion with multiple solutions. For example, chaos in the Pearl-Verhulst map model: x(t+1)=a.x(t).[1-x(t)] is controlled by the following anticipatory incursive model: x(t+1)=a.x(t).[1-x(t+1)] which corresponds to the differential anticipatory equation: dx(t)/dt=a.x(t).[1-x(t+1)]-x(t). The main part of this paper deals with the discretisation of differential equation systems of linear and non-linear oscillators. The non-linear oscillator is based on the Lotka-Volterra equations model. The discretisation is made by incursion. The incursive discrete equation system gives the same stability condition than the original differential equations without numerical instabilities. The linearisation of the incursive discrete non-linear Lotka-Volterra equation system gives rise to the classical harmonic oscillator. The incursive discretisation of the linear oscillator is similar to define backward and forward discrete derivatives. A generalized complex derivative is then considered and applied to the harmonic oscillator. Non-locality seems to be a property of anticipatory systems. With some mathematical assumption, the Schrödinger quantum equation is derived for a particle in a uniform potential. Finally an hyperincursive system is given in the case of a neural stack memory.

  4. Shear Bond Strength of Three Orthodontic Bonding Systems on Enamel and Restorative Materials.

    PubMed

    Hellak, Andreas; Ebeling, Jennifer; Schauseil, Michael; Stein, Steffen; Roggendorf, Matthias; Korbmacher-Steiner, Heike

    2016-01-01

    Objective. The aim of this in vitro study was to determine the shear bond strength (SBS) and adhesive remnant index (ARI) score of two self-etching no-mix adhesives (iBond ™ and Scotchbond ™ ) on different prosthetic surfaces and enamel, in comparison with the commonly used total etch system Transbond XT ™ . Materials and Methods . A total of 270 surfaces (1 enamel and 8 restorative surfaces, n = 30) were randomly divided into three adhesive groups. In group 1 (control) brackets were bonded with Transbond XT primer. In the experimental groups iBond adhesive (group 2) and Scotchbond Universal adhesive (group 3) were used. The SBS was measured using a Zwicki 1120 ™ testing machine. The ARI and SBS were compared statistically using the Kruskal-Wallis test ( P ≤ 0.05). Results . Significant differences in SBS and ARI were found between the control group and experimental groups. Conclusions . Transbond XT showed the highest SBS on human enamel. Scotchbond Universal on average provides the best bonding on all other types of surface (metal, composite, and porcelain), with no need for additional primers. It might therefore be helpful for simplifying bonding in orthodontic procedures on restorative materials in patients. If metal brackets have to be bonded to a metal surface, the use of a dual-curing resin is recommended.

  5. Integration of CW / Radionucleotide Detection Systems to the Fido XT Explosives Detector

    DTIC Science & Technology

    2008-07-31

    explosives detected by the Fido XT. Additionally, a platform for centralized storage and processing of Fido XT data files collected in house, targeted...fused silica glass wool (obtained from Restek). The fluorescent signal was easily washed out of the flow cell by a nominal amount of buffer...detector with supporting NRE was processed . The Interceptor components were configured to operate under a Windows CE processor environment, and to

  6. Performance evaluation of the Abbott CELL-DYN Ruby and the Sysmex XT-2000i haematology analysers.

    PubMed

    Leers, M P G; Goertz, H; Feller, A; Hoffmann, J J M L

    2011-02-01

    Two mid-range haematology analysers (Abbott CELL-DYN Ruby and Sysmex XT-2000i) were evaluated to determine their analytical performance and workflow efficiency in the haematology laboratory. In total 418 samples were processed for determining equivalence of complete blood count (CBC) measurements, and 100 for reticulocyte comparison. Blood smears served for assessing the agreement of the differential counts. Inter-instrument agreement for most parameters was good although small numbers of discrepancies were observed. Systematic biases were found for mean cell volume, reticulocytes, platelets and mean platelet volume. CELL-DYN Ruby WBC differentials were obtained with all samples while the XT-2000i suppressed differentials partially or completely in 13 samples (3.1%). WBC subpopulation counts were otherwise in good agreement with no major outliers. Following first-pass CBC/differential analysis, 88 (21%) of XT-2000i samples required further analyser processing compared to 18 (4.3%) for the CELL-DYN Ruby. Smear referrals for suspected WBC/nucleated red blood cells and platelet abnormalities were indicated for 106 (25.4%) and 95 (22.7%) of the XT-2000i and CELL-DYN Ruby samples respectively. Flagging efficiencies for both analysers were found to be similar. The Sysmex XT-2000i and Abbott CELL-DYN Ruby analysers have broadly comparable analytical performance, but the CELL-DYN Ruby showed superior first-pass efficiency. © 2010 Blackwell Publishing Ltd.

  7. Linear response to nonstationary random excitation.

    NASA Technical Reports Server (NTRS)

    Hasselman, T.

    1972-01-01

    Development of a method for computing the mean-square response of linear systems to nonstationary random excitation of the form given by y(t) = f(t) x(t), in which x(t) = a stationary process and f(t) is deterministic. The method is suitable for application to multidegree-of-freedom systems when the mean-square response at a point due to excitation applied at another point is desired. Both the stationary process, x(t), and the modulating function, f(t), may be arbitrary. The method utilizes a fundamental component of transient response dependent only on x(t) and the system, and independent of f(t) to synthesize the total response. The role played by this component is analogous to that played by the Green's function or impulse response function in the convolution integral.

  8. Sparse Bayesian Information Filters for Localization and Mapping

    DTIC Science & Technology

    2008-02-01

    a set of smaller, more manageable maps [76, 51, 139, 77, 12]. These appropriately-named submap algorithms greatly reduce the effects of map size on...An intuitive way of dealing with this limitation is to divide the world into numerous sub-environments, each comprised of a more manageable number of...p (xt, M I z t , u t) = p (M I xt, zt) • p (xt zt, ut) (2.16) 6 This assumes knowledge of the mean, which is necessary for observations that are

  9. Self-expanding Portico Valve Versus Balloon-expandable SAPIEN XT Valve in Patients With Small Aortic Annuli: Comparison of Hemodynamic Performance.

    PubMed

    Del Trigo, María; Dahou, Abdellaziz; Webb, John G; Dvir, Danny; Puri, Rishi; Abdul-Jawad Altisent, Omar; Campelo-Parada, Francisco; Thompson, Chris; Leipsic, Jonathon; Stub, Dion; DeLarochellière, Robert; Paradis, Jean-Michel; Dumont, Eric; Doyle, Daniel; Mohammadi, Siamak; Pasian, Sergio; Côté, Melanie; Pibarot, Philippe; Rodés-Cabau, Josep

    2016-05-01

    The self-expanding Portico valve is a new transcatheter aortic valve system yielding promising preliminary results, yet there are no comparative data against earlier generation transcatheter aortic valve systems. The aim of this study was to compare the hemodynamic performance of the Portico and balloon-expandable SAPIEN XT valves in a case-matched study with echocardiographic core laboratory analysis. Twenty-two patients underwent transcatheter aortic valve implantation with the Portico 23-mm valve and were matched for aortic annulus area and mean diameter measured by multidetector computed tomography, left ventricular ejection fraction, body surface area, and body mass index with 40 patients treated with the 23-mm SAPIEN XT. Mean aortic annulus diameters were 19.6±1.3mm by transthoracic echocardiography and 21.4±1.2mm by computed tomography, with no significant between-group differences. Doppler echocardiographic images were collected at baseline and at 1-month of follow-up and were analyzed in a central echocardiography core laboratory. There were no significant between-group differences in residual mean transaortic gradients (SAPIEN XT: 10.4±3.7mmHg; Portico: 9.8±1.1mmHg; P=.49) and effective orifice areas (SAPIEN XT: 1.36±0.27cm(2); Portico, 1.37±.29cm(2); P=.54). Rates of severe prosthesis-patient mismatch (effective orifice area<0.65cm(2)/m(2)) were similar (SAPIEN XT: 13.5%; Portico: 10.0%; P=.56). No between-group differences were found in the occurrence of moderate-severe paravalvular leaks (5.0% vs 4.8% of SAPIEN XT and Portico respectively; P=.90). Transcatheter aortic valve implantation with the self-expanding Portico system yielded similar short-term hemodynamic performance compared with the balloon-expandable SAPIEN XT system for treating patients with severe aortic stenosis and small annuli. Further prospective studies with longer-term follow-up and in patients with larger aortic annuli are required. Copyright © 2015 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

  10. Using Noldus Observer XT for research on deaf signers learning to read: an innovative methodology.

    PubMed

    Ducharme, Daphne A; Arcand, Isabelle

    2009-08-01

    Despite years of research on the reading problems of deaf students, we still do not know how deaf signers who read well actually crack the code of print. How connections are made between sign language and written language is still an open question. In this article, we show how the Noldus Observer XT software can be used to conduct an in-depth analysis of the online behavior of deaf readers. First, we examine factors that may have an impact on reading behavior. Then, we describe how we videotaped teachers with their deaf student signers of langue des signes québécoise during a reading task, how we conducted a recall activity to better understand the students' reading behavior, and how we used this innovative software to analyze the taped footage. Finally, we discuss the contribution this type of research can have on the future reading behavior of deaf students.

  11. Effect of bleaching on color stability and roughness of composite resins aged in staining beverage.

    PubMed

    Rodrigues, Camila Silva; Mozzaquatro, Lisandra Rossato; Dala Nora, Bárbara; Jacques, Letícia Borges; Mallmann, André

    2017-01-01

    Composite resin properties can be affected by contact with gel during bleaching procedures; however, there is no consensus about the effect of this contact on resin susceptibility to color change. This study aimed to evaluate staining susceptibility and surface roughness changes in 2 composite resins (Filtek Z250 XT and Filtek Z350 XT) after application of bleaching peroxides and storage in different media. Forty-two disc-shaped specimens of each composite were made, polished, and divided into 3 groups according to treatment type (35% hydrogen peroxide, 16% carbamide peroxide, or deionized water as a control group). These groups were subdivided into 2 groups according to immersion media (n = 7): deionized water or red wine. Color and average roughness (Ra) measurements were taken 24 hours after specimen preparation (T0), immediately after bleaching procedures (T1), and immediately after aging (staining; T2). Statistical analyses were performed using 2-way analyses of variance for repeated measurements and the Tukey test (P < 0.05). Bleaching resulted in minimal color change (ΔE* < 1) in all groups. Filtek Z350 XT specimens presented greater mean values of color change. The Ra values did not increase significantly after bleaching procedures or aging (staining) in all groups. Thus, bleaching agents did not significantly change the color or roughness of the composite resins used in this study.

  12. Effect of Accelerated Artificial Aging on Translucency of Methacrylate and Silorane-Based Composite Resins.

    PubMed

    Shirinzad, Mehdi; Rezaei-Soufi, Loghman; Mirtorabi, Maryam Sadat; Vahdatinia, Farshid

    2016-03-01

    Composite restorations must have tooth-like optical properties namely color and translucency and maintain them for a long time. This study aimed to compare the effect of accelerated artificial aging (AAA) on the translucency of three methacrylate-based composites (Filtek Z250, Filtek Z250XT and Filtek Z350XT) and one silorane-based composite resin (Filtek P90). For this in vitro study, 56 composite discs were fabricated (n=14 for each group). Using scanning spectrophotometer, CIE L*a*b* parameters and translucency of each specimen were measured at 24 hours and after AAA for 384 hours. Data were analyzed using one-way ANOVA, Tukey's test and paired t-test at P=0.05 level of significance. The mean (±standard deviation) translucency parameter for Filtek Z250, Filtek Z250XT, Filtek Z350XT and Filtek P90 was 5.67±0.64, 4.59±0.77, 7.87±0.82 and 4.21±0.71 before AAA and 4.25±0.615, 3.53±0.73, 5.94±0.57 and 4.12±0.54 after AAA, respectively. After aging, the translucency of methacrylate-based composites decreased significantly (P<0.05). However, the translucency of Filtek P90 did not change significantly (P>0.05). The AAA significantly decreased the translucency of methacrylate-based composites (Filtek Z250, Filtek Z250XT and Filtek Z350XT) but no change occurred in the translucency of Filtek P90 silorane-based composite.

  13. Effect of Accelerated Artificial Aging on Translucency of Methacrylate and Silorane-Based Composite Resins

    PubMed Central

    Shirinzad, Mehdi; Rezaei-Soufi, Loghman; Mirtorabi, Maryam Sadat; Vahdatinia, Farshid

    2016-01-01

    Objectives: Composite restorations must have tooth-like optical properties namely color and translucency and maintain them for a long time. This study aimed to compare the effect of accelerated artificial aging (AAA) on the translucency of three methacrylate-based composites (Filtek Z250, Filtek Z250XT and Filtek Z350XT) and one silorane-based composite resin (Filtek P90). Materials and Methods: For this in vitro study, 56 composite discs were fabricated (n=14 for each group). Using scanning spectrophotometer, CIE L*a*b* parameters and translucency of each specimen were measured at 24 hours and after AAA for 384 hours. Data were analyzed using one-way ANOVA, Tukey's test and paired t-test at P=0.05 level of significance. Results: The mean (±standard deviation) translucency parameter for Filtek Z250, Filtek Z250XT, Filtek Z350XT and Filtek P90 was 5.67±0.64, 4.59±0.77, 7.87±0.82 and 4.21±0.71 before AAA and 4.25±0.615, 3.53±0.73, 5.94±0.57 and 4.12±0.54 after AAA, respectively. After aging, the translucency of methacrylate-based composites decreased significantly (P<0.05). However, the translucency of Filtek P90 did not change significantly (P>0.05). Conclusions: The AAA significantly decreased the translucency of methacrylate-based composites (Filtek Z250, Filtek Z250XT and Filtek Z350XT) but no change occurred in the translucency of Filtek P90 silorane-based composite. PMID:27928237

  14. Spectral assessment of new ASTER SWIR surface reflectance data products for spectroscopic mapping of rocks and minerals

    USGS Publications Warehouse

    Mars, J.C.; Rowan, L.C.

    2010-01-01

    ASTER reflectance spectra from Cuprite, Nevada, and Mountain Pass, California, were compared to spectra of field samples and to ASTER-resampled AVIRIS reflectance data to determine spectral accuracy and spectroscopic mapping potential of two new ASTER SWIR reflectance datasets: RefL1b and AST_07XT. RefL1b is a new reflectance dataset produced for this study using ASTER Level 1B data, crosstalk correction, radiance correction factors, and concurrently acquired level 2 MODIS water vapor data. The AST_07XT data product, available from EDC and ERSDAC, incorporates crosstalk correction and non-concurrently acquired MODIS water vapor data for atmospheric correction. Spectral accuracy was determined using difference values which were compiled from ASTER band 5/6 and 9/8 ratios of AST_07XT or RefL1b data subtracted from similar ratios calculated for field sample and AVIRIS reflectance data. In addition, Spectral Analyst, a statistical program that utilizes a Spectral Feature Fitting algorithm, was used to quantitatively assess spectral accuracy of AST_07XT and RefL1b data.Spectral Analyst matched more minerals correctly and had higher scores for the RefL1b data than for AST_07XT data. The radiance correction factors used in the RefL1b data corrected a low band 5 reflectance anomaly observed in the AST_07XT and AST_07 data but also produced anomalously high band 5 reflectance in RefL1b spectra with strong band 5 absorption for minerals, such as alunite. Thus, the band 5 anomaly seen in the RefL1b data cannot be corrected using additional gain adjustments. In addition, the use of concurrent MODIS water vapor data in the atmospheric correction of the RefL1b data produced datasets that had lower band 9 reflectance anomalies than the AST_07XT data. Although assessment of spectral data suggests that RefL1b data are more consistent and spectrally more correct than AST_07XT data, the Spectral Analyst results indicate that spectral discrimination between some minerals, such as alunite and kaolinite, are still not possible unless additional spectral calibration using site specific spectral data are performed. ?? 2010.

  15. Modified Y-splitting Procedure for the Treatment of Duane Retraction Syndrome.

    PubMed

    Altıntaş, Ayşe Gül; Arifoğlu, Hasan Basri; Köklü, Şükrü Gültekin

    2015-08-01

    To present the outcomes of modified lateral rectus Y-splitting combined with either unilateral or bilateral horizontal rectus recession in Duane Retraction Syndrome (DRS) with significant upshoot or downshoot. A total of 12 patients including 10 patients with Type I DRS and 2 with Type III DRS underwent modified Y-splitting surgery. Amount of additional recessions varied with the degree of preoperative deviation by intraoperative adjustable suture technique. Preoperatively 3 patients had esotropia (ET), 6 had exotropia (XT), and 3 patients had orthotropia. The mean preoperative deviation was 19.3 prism diopters (PD) (range, 18-20 PD) in ET patients and 19.2 PD (range, 16-20 PD) in XT patients. Postoperatively, all patients had significant correction in horizontal deviation and aligned within 4 PD of orthotropia, and no patients exhibited abnormal head posture. Co-contraction and globe retraction were markedly reduced and abnormal ocular vertical movement disappeared or significantly decreased in all cases. No patients experienced recurrence of ocular motility disorders in the mean 26-month (range, 13-66 months) follow-up period. Modified Y-splitting surgery combined with co-contracting horizontal muscle recession technique seems to be a safe and effective treatment in DRS.

  16. Approximating Smooth Step Functions Using Partial Fourier Series Sums

    DTIC Science & Technology

    2012-09-01

    interp1(xt(ii), smoothstepbez( t(ii), min(t(ii)), max(t(ii)), ’y’), t(ii), ’linear’, ’ extrap ’); ii = find( abs(t - tau/2) <= epi ); iii = t(ii...interp1( xt(ii), smoothstepbez( rt, min(rt), max(rt), ’y’), t(ii), ’linear’, ’ extrap ’ ); % stepm(ii) = 1 - interp1(xt(ii), smoothstepbez( t(ii...min(t(ii)), max(t(ii)), ’y’), t(ii), ’linear’, ’ extrap ’); In this case, because x is also defined as a function of the independent parameter

  17. Chlorhexidine stabilizes the adhesive interface: a 2 year in vitro study

    PubMed Central

    Breschi, Lorenzo; Mazzoni, Annalisa; Nato, Fernando; Carrilho, Marcela; Visintini, Erika; Tjäderhane, Leo; Ruggeri, Alessandra; Tay, Franklin R; De Stefano Dorigo, Elettra; Pashley, David H

    2013-01-01

    Objectives This study evaluated the role of endogenous dentin MMPs in auto-degradation of collagen fibrils within adhesive-bonded interfaces. The null hypotheses tested were that adhesive blends or chlorhexidine digluconate (CHX) application does not modify dentin MMPs activity and that CHX used as therapeutic primer does not improve the stability of adhesive interfaces over time. Methods Zymograms of protein extracts from human dentin powder incubated with Adper Scotchbond 1XT (SB1XT) on untreated or 0.2–2% CHX treated dentin were obtained to assay dentin MMPs activity. Microtensile bond strength and interfacial nanoleakage expression of SB1XT bonded interfaces (with or without CHX pre-treatment for 30s on the etched surface) were analyzed immediately and after 2 yr of storage in artificial saliva at 37°C. Results Zymograms showed that application of SB1XT to human dentin powder increases MMP-2 activity, while CHX pre-treatment inhibited all dentin gelatinolytic activity, irrespective from the tested concentration. CHX significantly lowered the loss of bond strength and nanoleakage seen in acid-etched resin-bonded dentin artificially aged for 2 yr. Significance The study demonstrates the active role of SB1XT in dentin MMP-2 activation and the efficacy of CHX inhibition of MMPs even if used at low concentration (0.2%). PMID:20045177

  18. Multi-Scale Correlative Tomography of a Li-Ion Battery Composite Cathode

    PubMed Central

    Moroni, Riko; Börner, Markus; Zielke, Lukas; Schroeder, Melanie; Nowak, Sascha; Winter, Martin; Manke, Ingo; Zengerle, Roland; Thiele, Simon

    2016-01-01

    Focused ion beam/scanning electron microscopy tomography (FIB/SEMt) and synchrotron X-ray tomography (Xt) are used to investigate the same lithium manganese oxide composite cathode at the same specific spot. This correlative approach allows the investigation of three central issues in the tomographic analysis of composite battery electrodes: (i) Validation of state-of-the-art binary active material (AM) segmentation: Although threshold segmentation by standard algorithms leads to very good segmentation results, limited Xt resolution results in an AM underestimation of 6 vol% and severe overestimation of AM connectivity. (ii) Carbon binder domain (CBD) segmentation in Xt data: While threshold segmentation cannot be applied for this purpose, a suitable classification method is introduced. Based on correlative tomography, it allows for reliable ternary segmentation of Xt data into the pore space, CBD, and AM. (iii) Pore space analysis in the micrometer regime: This segmentation technique is applied to an Xt reconstruction with several hundred microns edge length, thus validating the segmentation of pores within the micrometer regime for the first time. The analyzed cathode volume exhibits a bimodal pore size distribution in the ranges between 0–1 μm and 1–12 μm. These ranges can be attributed to different pore formation mechanisms. PMID:27456201

  19. Draft genome sequence of a KPC-2-producing Klebsiella pneumoniae ST340 carrying blaCTX-M-15 and blaCTX-M-59 genes: a rich genome of mobile genetic elements and genes encoding antibiotic resistance.

    PubMed

    Casella, Tiago; de Morais, Andressa Batista Zequini; de Paula Barcelos, Diego Diniz; Tolentino, Fernanda Modesto; Cerdeira, Louise Teixeira; Bueno, Maria Fernanda Campagnari; Francisco, Gabriela Rodrigues; de Andrade, Leonardo Neves; da Costa Darini, Ana Lucia; de Oliveira Garcia, Doroti; Lincopan, Nilton; Nogueira, Mara Corrêa Lelles

    2018-06-01

    Klebsiella pneumoniae is considered an opportunistic pathogen and an important agent of nosocomial and community infections. It presents the ability to capture and harbour several antimicrobial resistance genes and, in this context, the extensive use of carbapenems to treat serious infections has been responsible for the selection of several resistance genes. This study reports the draft genome sequence of a KPC-2-producing K. pneumoniae strain (Kp10) simultaneously harbouring bla CTX-M-15 and bla CTX-M-59 genes isolated from urine culture of a patient with Parkinson's disease. Classical microbiological methods were applied to isolate and identify the strain, and PCR and sequencing were used to identify and characterise the genes and the genetic environment. Whole-genome sequencing (WGS) was performed using a Nextera XT DNA library and a NextSeq platform. WGS analysis revealed the presence of 5915 coding genes, 46 RNA-encoding genes and 255 pseudogenes. Kp10 belonged to sequence type 340 (ST340) of clonal complex 258 (CC258) and carried 20 transferable genes associated with antimicrobial resistance, comprising seven drug classes. Although the simultaneous presence of different bla CTX-M genes in the same strain is rarely reported, the bla KPC-2 , bla CTX-M-15 and bla CTX-M-59 genes were not associated with the same genetic mobile structure in Kp10. These results confirm the capacity of K. pneumoniae to harbour several antimicrobial resistance genes. Thus, this draft genome could help in future epidemiological studies regarding the dissemination of clinically relevant resistance genes. Copyright © 2018 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.

  20. Polymerization shrinkage stresses in different restorative techniques for non-carious cervical lesions.

    PubMed

    de Oliveira Correia, Ayla Macyelle; Tribst, João Paulo Mendes; de Souza Matos, Felipe; Platt, Jeffrey A; Caneppele, Taciana Marco Ferraz; Borges, Alexandre Luiz Souto

    2018-06-20

    This study evaluated the effect of different restorative techniques for non-carious cervical lesions (NCCL) on polymerization shrinkage stress of resins using three-dimensional (3D) finite element analysis (FEA). 3D-models of a maxillary premolar with a NCCL restored with different filling techniques (bulk filling and incremental) were generated to be compared by nonlinear FEA. The bulk filling technique was used for groups B (NCCL restored with Filtek™ Bulk Fill) and C (Filtek™ Z350 XT). The incremental technique was subdivided according to mode of application: P (2 parallel increments of the Filtek™ Z350 XT), OI (2 oblique increments of the Filtek™ Z350 XT, with incisal first), OIV (2 oblique increments of the Filtek™ Z350 XT, with incisal first and increments with the same volume), OG (2 oblique increments of the Filtek™ Z350 XT, with gingival first) and OGV (2 oblique increments of the Filtek™ Z350 XT, with gingival first and increments with the same volume), resulting in 7 models. All materials were considered isotropic, elastic and linear. The results were expressed in maximum principal stress (MPS). The tension stress distribution was influenced by the restorative technique. The lowest stress concentration occurred in group B followed by OG, OGV, OI, OIV, P and C; the incisal interface was more affected than the gingival. The restoration of NCCLs with bulk fill composite resulted in lower shrinkage stress in the gingival and incisal areas, followed by incremental techniques with the initial increment placed on the gingival wall. The non-carious cervical lesions (NCCLs) restored with bulk fill composite have a more favorable biomechanical behavior. Copyright © 2018. Published by Elsevier Ltd.

  1. Perturbation theory for fractional Brownian motion in presence of absorbing boundaries.

    PubMed

    Wiese, Kay Jörg; Majumdar, Satya N; Rosso, Alberto

    2011-06-01

    Fractional Brownian motion is a Gaussian process x(t) with zero mean and two-time correlations (x(t(1))x(t(2)))=D(t(1)(2H)+t(2)(2H)-|t(1)-t(2)|(2H)), where H, with 0

  2. Finite-Size Scaling Analysis of Binary Stochastic Processes and Universality Classes of Information Cascade Phase Transition

    NASA Astrophysics Data System (ADS)

    Mori, Shintaro; Hisakado, Masato

    2015-05-01

    We propose a finite-size scaling analysis method for binary stochastic processes X(t) in { 0,1} based on the second moment correlation length ξ for the autocorrelation function C(t). The purpose is to clarify the critical properties and provide a new data analysis method for information cascades. As a simple model to represent the different behaviors of subjects in information cascade experiments, we assume that X(t) is a mixture of an independent random variable that takes 1 with probability q and a random variable that depends on the ratio z of the variables taking 1 among recent r variables. We consider two types of the probability f(z) that the latter takes 1: (i) analog [f(z) = z] and (ii) digital [f(z) = θ(z - 1/2)]. We study the universal functions of scaling for ξ and the integrated correlation time τ. For finite r, C(t) decays exponentially as a function of t, and there is only one stable renormalization group (RG) fixed point. In the limit r to ∞ , where X(t) depends on all the previous variables, C(t) in model (i) obeys a power law, and the system becomes scale invariant. In model (ii) with q ≠ 1/2, there are two stable RG fixed points, which correspond to the ordered and disordered phases of the information cascade phase transition with the critical exponents β = 1 and ν|| = 2.

  3. Near-Range Receiver Unit of Next Generation PollyXT Used with Koldeway Aerosol Raman Lidar in Arctic

    NASA Astrophysics Data System (ADS)

    Stachlewska, Iwona S.; Markowicz, Krzysztof M.; Ritter, Christoph; Neuber, Roland; Heese, Birgit; Engelmann, Ronny; Linne, Holger

    2016-06-01

    The Near-range Aerosol Raman lidar (NARLa) receiver unit, that was designed to enhance the detection range of the NeXT generation PollyXT Aerosol-Depolarization-Raman (ADR) lidar of the University of Warsaw, was employed next the Koldeway Aerosol Raman Lidar (KARL) at the AWI-IPEV German-French station in Arctic during Spring 2015. Here we introduce shortly design of both lidars, the scheme of their installation next to each other, and preliminary results of observations aiming at arctic haze investigation by the lidars and the iCAP a set of particle counter and aethalometer installed under a tethered balloon.

  4. Hard x-ray imager for the NeXT mission

    NASA Astrophysics Data System (ADS)

    Nakazawa, Kazuhiro; Fukazawa, Yasushi; Kamae, Tuneyoshi; Kataoka, Jun; Kokubun, Motohide; Makishima, Kazuo; Mizuno, Tsunefumi; Murakami, Toshio; Nomachi, Masaharu; Tajima, Hiroyasu; Takahashi, Tadayuki; Tashiro, Makoto; Tamagawa, Toru; Terada, Yukikatsu; Watanabe, Shin; Yamaoka, Kazutaka; Yonetoku, Daisuke

    2006-06-01

    The hard X-ray imager (HXI) is the primary detector of the NeXT mission, proposed to explore high-energy non-thermal phenomena in the universe. Combined with a novel hard X-ray mirror optics, the HXI is designed to provide better than arc-minutes imaging capability with 1 keV level spectroscopy, and more than 30 times higher sensitivity compared with any existing hard X-ray instruments. The base-line design of the HXI is improving to secure high sensitivity. The key is to reduce the detector background as far as possible. Based on the experience of the Suzaku satellite launched in July 2005, the current design has a well-type tight active shield and multi layered, multi material imaging detector made of Si and CdTe. Technology has been under development for a few years so that we have reached the level where a basic detector performance is satisfied. Design tuning to further improve the sensitivity and reliability is on-going.

  5. Fast Numerical Methods for Stochastic Partial Differential Equations

    DTIC Science & Technology

    2016-04-15

    analysis we first derived a system of forward and backward SDEs (BSDEs) for (Xt, Qt, Zt){ dXs = b( Xs )dt+ σsdWs, Xt = x, t < s < T, (SDE) dQs = ZsdWs...g( Xs )QsdVs, QT = Φ(XT ). (BSDE) (6) Here Wt and Vt are two independent Brownian motions. The first equation in (6) is a forward SDE while the second...first order scheme for a general coupled system of forward-backward SDEs [1]: dXs = b( Xs )ds+ σ( Xs )dWs, t ≤ s ≤ T, dYs = +f(s, Xs , Ys)ds +g(s

  6. Proton spectral editing in the inhomogeneous radiofrequency field of a surface coil using modified stimulated echoes.

    PubMed

    Lahrech, H; Briguet, A

    1990-11-01

    It is shown that the modified stimulated echo sequence, [theta](+/- x +/- y)-t1-[theta](+ x)-t2/2-[2 theta](+ x)-t2/2- [theta](+ x)-t1-Acq(+/- x +/- y), denoted as MSTE[2 theta]x according to the exciter phase of the 2 theta pulse, is able to perform proton spectral editing without difference spectra. On the other hand, this sequence appears to be suitable for spatial localization. Sensitivity and spatial selectivity of MSTE and conventional stimulated echo sequence (STE) are briefly compared. MSTE is applied to editing lactate in the rat brain using the locally restricted excitation of a surface coil.

  7. INNOVATIVE TECHNOLOGY VERIFICATION REPORT XRF TECHNOLOGIES FOR MEASURING TRACE ELEMENTS IN SOIL AND SEDIMENT XCALIBUR ELVAX XRF ANALYZER

    EPA Science Inventory

    The Innov-X XT400 Series (XT400) x-ray fluorescence (XRF) analyzer was demonstrated under the U.S. Environmental Protection Agency (EPA) Superfund Innovative Technology Evaluation (SITE) Program. The field portion of the demonstration was conducted in January 2005 at the Kenned...

  8. A College That Relied on NeXT Computers Plans To Switch to Apple.

    ERIC Educational Resources Information Center

    Wilson, David L.

    1997-01-01

    Allegheny College (Pennsylvania), which uses NeXT computers, was dismayed when the technically superior operating system was orphaned but are now delighted that the company has been bought by Apple Computer and will make the operating system standard on Apple computers. The object-oriented operating system allows relatively unsophisticated users…

  9. Effect of randomness in logistic maps

    NASA Astrophysics Data System (ADS)

    Khaleque, Abdul; Sen, Parongama

    2015-01-01

    We study a random logistic map xt+1 = atxt[1 - xt] where at are bounded (q1 ≤ at ≤ q2), random variables independently drawn from a distribution. xt does not show any regular behavior in time. We find that xt shows fully ergodic behavior when the maximum allowed value of at is 4. However , averaged over different realizations reaches a fixed point. For 1 ≤ at ≤ 4, the system shows nonchaotic behavior and the Lyapunov exponent is strongly dependent on the asymmetry of the distribution from which at is drawn. Chaotic behavior is seen to occur beyond a threshold value of q1(q2) when q2(q1) is varied. The most striking result is that the random map is chaotic even when q2 is less than the threshold value 3.5699⋯ at which chaos occurs in the nonrandom map. We also employ a different method in which a different set of random variables are used for the evolution of two initially identical x values, here the chaotic regime exists for all q1 ≠ q2 values.

  10. Crosstalk-aware virtual network embedding over inter-datacenter optical networks with few-mode fibers

    NASA Astrophysics Data System (ADS)

    Huang, Haibin; Guo, Bingli; Li, Xin; Yin, Shan; Zhou, Yu; Huang, Shanguo

    2017-12-01

    Virtualization of datacenter (DC) infrastructures enables infrastructure providers (InPs) to provide novel services like virtual networks (VNs). Furthermore, optical networks have been employed to connect the metro-scale geographically distributed DCs. The synergistic virtualization of the DC infrastructures and optical networks enables the efficient VN service over inter-DC optical networks (inter-DCONs). While the capacity of the used standard single-mode fiber (SSMF) is limited by their nonlinear characteristics. Thus, mode-division multiplexing (MDM) technology based on few-mode fibers (FMFs) could be employed to increase the capacity of optical networks. Whereas, modal crosstalk (XT) introduced by optical fibers and components deployed in the MDM optical networks impacts the performance of VN embedding (VNE) over inter-DCONs with FMFs. In this paper, we propose a XT-aware VNE mechanism over inter-DCONs with FMFs. The impact of XT is considered throughout the VNE procedures. The simulation results show that the proposed XT-aware VNE can achieves better performances of blocking probability and spectrum utilization compared to conventional VNE mechanisms.

  11. Comparison of shear bond strengths of conventional orthodontic composite and nano-ceramic restorative composite: an in vitro study.

    PubMed

    Nagar, Namit; Vaz, Anna C

    2013-01-01

    To compare the shear bond strength of a nano-ceramic restorative composite Ceram-X Mono(TM♦), a restorative resin with the traditional orthodontic composite Transbond XT(TM†) and to evaluate the site of bond failure using Adhesive Remnant Index. Sixty extracted human premolars were divided into two groups of 30 each. Stainless steel brackets were bonded using Transbond XT(TM†) (Group I) and Ceram-X Mono(TM♦) (Group II) according to manufacturer's protocol. Shear bond strength was measured on Universal testing machine at crosshead speed of 1 mm/minute. Adhesive Remnant Index scores were assigned to debonded brackets of each group. Data was analyzed using unpaired 't' test and Chi square test. The mean shear bond strength of Group I (Transbond XT(TM†)) was 12.89 MPa ± 2.19 and that of Group II (Ceram-X Mono(TM)) was 7.29 MPa ± 1.76. Unpaired 't' test revealed statistically significant differences amongst the shear bond strength of the samples measured. Chi-square test revealed statistically insignificant differences amongst the ARI scores of the samples measured. Ceram-X Mono(TM♦) had a lesser mean shear bond strength when compared to Transbond XT(TM†) which was statistically significant difference. However, the mean shear bond of Ceram X Mono was within the clinically acceptable range for bonding. Ceram-X Mono(TM†) and Transbond XT(TM†) showed cohesive fracture of adhesive in 72.6% and 66.6% of the specimens, respectively.

  12. Conduction Abnormalities and Pacemaker Implantations After SAPIEN 3 Vs SAPIEN XT Prosthesis Aortic Valve Implantation.

    PubMed

    Husser, Oliver; Kessler, Thorsten; Burgdorf, Christof; Templin, Christian; Pellegrini, Costanza; Schneider, Simon; Kasel, Albert Markus; Kastrati, Adnan; Schunkert, Heribert; Hengstenberg, Christian

    2016-02-01

    Transcatheter aortic valve implantation is increasingly used in patients with aortic stenosis. Post-procedural intraventricular conduction abnormalities and permanent pacemaker implantations remain a serious concern. Recently, the Edwards SAPIEN 3 prosthesis has replaced the SAPIEN XT. We sought to determine the incidences of new-onset intraventricular conduction abnormalities and permanent pacemaker implantations by comparing the 2 devices. We analyzed the last consecutive 103 patients undergoing transcatheter aortic valve implantation with SAPIEN XT before SAPIEN 3 was used in the next 105 patients. To analyze permanent pacemaker implantations and new-onset intraventricular conduction abnormalities, patients with these conditions at baseline were excluded. Electrocardiograms were recorded at baseline, after the procedure, and before discharge. SAPIEN 3 was associated with higher device success (100% vs 92%; P=.005) and less paravalvular leakage (0% vs 7%; P<.001). The incidence of permanent pacemaker implantations was 12.6% (23 of 183) with no difference between the 2 groups (SAPIEN 3: 12.5% [12 of 96] vs SAPIEN XT: 12.6% [11 of 87]; P=.99). SAPIEN 3 was associated with a higher rate of new-onset intraventricular conduction abnormalities (49% vs 27%; P=.007) due to a higher rate of fascicular blocks (17% vs 5%; P=.021). There was no statistically significant difference in transient (29% [20 of 69] vs persistent 19% [12 of 64]; P=.168) left bundle branch blocks (28% [19 of 69] vs 17% [11 of 64]; P=.154) when SAPIEN 3 was compared with SAPIEN XT. We found a trend toward a higher rate of new-onset intraventricular conduction abnormalities with SAPIEN 3 compared with SAPIEN XT, although this did not result in a higher permanent pacemaker implantation rate. Copyright © 2015 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

  13. Evaluation of estimation methods for organic carbon normalized sorption coefficients

    USGS Publications Warehouse

    Baker, James R.; Mihelcic, James R.; Luehrs, Dean C.; Hickey, James P.

    1997-01-01

    A critically evaluated set of 94 soil water partition coefficients normalized to soil organic carbon content (Koc) is presented for 11 classes of organic chemicals. This data set is used to develop and evaluate Koc estimation methods using three different descriptors. The three types of descriptors used in predicting Koc were octanol/water partition coefficient (Kow), molecular connectivity (mXt) and linear solvation energy relationships (LSERs). The best results were obtained estimating Koc from Kow, though a slight improvement in the correlation coefficient was obtained by using a two-parameter regression with Kow and the third order difference term from mXt. Molecular connectivity correlations seemed to be best suited for use with specific chemical classes. The LSER provided a better fit than mXt but not as good as the correlation with Koc. The correlation to predict Koc from Kow was developed for 72 chemicals; log Koc = 0.903* log Kow + 0.094. This correlation accounts for 91% of the variability in the data for chemicals with log Kow ranging from 1.7 to 7.0. The expression to determine the 95% confidence interval on the estimated Koc is provided along with an example for two chemicals of different hydrophobicity showing the confidence interval of the retardation factor determined from the estimated Koc. The data showed that Koc is not likely to be applicable for chemicals with log Kow < 1.7. Finally, the Koc correlation developed using Kow as a descriptor was compared with three nonclass-specific correlations and two 'commonly used' class-specific correlations to determine which method(s) are most suitable.

  14. 75 FR 17434 - In the Matter of Certain Personal Data and Mobile Communications Devices and Related Software...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-06

    ... Mobile Communications Devices and Related Software; Notice of Investigation AGENCY: U.S. International... Apple Computer, Inc. of Cupertino, California and NeXT Software, Inc. f/k/a NeXT Computer, Inc. of... certain personal data and mobile communications devices and related software by reason of infringement of...

  15. Accuracy Progressive Calculation of Lagrangian Trajectories from Gridded Velocity Field

    DTIC Science & Technology

    2014-01-01

    traced (Vries and Doos 2001). The two types of velocity are convertible. Routine ocean data 36 assimilation systems (Galanis et al. 2006; Lozano et...1b) 54 The position of each fluid particle, R(t) = [x(t), y(t), z(t)], is specified in the Lagrangian system . 55 The connection...coordinate 233 system at the southwest corner (Fig. 6). The x*- and y*- axes point eastward and northward, 234 respectively. Here, the superscript

  16. The Effect of a Combination of Implant Controller and Handpiece from Different Manufacturers on the Torque Value.

    PubMed

    Lee, Du-Hyeong; Kim, Yong-Gun; Lee, Jong-Ho; Hong, Sam-Pyo; Lim, Young-Jun; Lee, Kyu-Bok

    2015-01-01

    To determine the accuracy of applied torque of different implant controller and handpiece combinations by using an electronic torque gauge. Four combinations of the following devices were tested: Surgic XT controller (NSK), XIP10 controller (Saeshin), X-SG20L handpiece (NSK), CRB26LX handpiece (Saeshin). For five torque settings, 30 measurements were recorded at 30 revolutions per minute by using an electronic torque gauge fixed to jigs, and means were calculated. Applied torques were generally higher than the set torque of 10 and 20 Ncm and lower than the set values of 40 and 50 Ncm. The average torque deviations differed significantly among the combinations (P < .05). At 10 and 20 Ncm, the Surgic XT/X-SG20L combination yielded the closest value to the intended torque, followed by the XIP10/X-SG20L combination. At 30 Ncm, the XIP10/X-SG20L combination showed the nearest value. At 40 Ncm, the Surgic XT/X-SG20L, XIP10/CRB26LX, and XIP10/X-SG20L combinations showed deviations within 10%. At 50 Ncm, all the combinations showed lower applied torque than the set value. Large standard deviations were observed in the Surgic XT/CRB26LX (13.288) and Surgic XT/X-SG20L (7.858) combinations. Different combinations of implant controllers and handpieces do not generate significant variations in applied torque. The actual torque varies according to the torque setting. It is necessary to calibrate devices before use to reduce potentially problematic torque.

  17. Dietary supplementation of young broiler chickens with Capsicum and turmeric oleoresins increases resistance to necrotic enteritis.

    PubMed

    Lee, Sung Hyen; Lillehoj, Hyun S; Jang, Seung I; Lillehoj, Erik P; Min, Wongi; Bravo, David M

    2013-09-14

    The Clostridium-related poultry disease, necrotic enteritis (NE), causes substantial economic losses on a global scale. In the present study, a mixture of two plant-derived phytonutrients, Capsicum oleoresin and turmeric oleoresin (XT), was evaluated for its effects on local and systemic immune responses using a co-infection model of experimental NE in commercial broilers. Chickens were fed from hatch with a diet supplemented with XT, or with a non-supplemented control diet, and either uninfected or orally challenged with virulent Eimeria maxima oocysts at 14 d and Clostridium perfringens at 18 d of age. Parameters of protective immunity were as follows: (1) body weight; (2) gut lesions; (3) serum levels of C. perfringens α-toxin and NE B-like (NetB) toxin; (4) serum levels of antibodies to α-toxin and NetB toxin; (5) levels of gene transcripts encoding pro-inflammatory cytokines and chemokines in the intestine and spleen. Infected chickens fed the XT-supplemented diet had increased body weight and reduced gut lesion scores compared with infected birds given the non-supplemented diet. The XT-fed group also displayed decreased serum α-toxin levels and reduced intestinal IL-8, lipopolysaccharide-induced TNF-α factor (LITAF), IL-17A and IL-17F mRNA levels, while cytokine/chemokine levels in splenocytes increased in the XT-fed group, compared with the animals fed the control diet. In conclusion, the present study documents the molecular and cellular immune changes following dietary supplementation with extracts of Capsicum and turmeric that may be relevant to protective immunity against avian NE.

  18. Accuracy of the Garmin 920 XT HRM to perform HRV analysis.

    PubMed

    Cassirame, Johan; Vanhaesebrouck, Romain; Chevrolat, Simon; Mourot, Laurent

    2017-12-01

    Heart rate variability (HRV) analysis is widely used to investigate autonomous cardiac drive. This method requires periodogram measurement, which can be obtained by an electrocardiogram (ECG) or from a heart rate monitor (HRM), e.g. the Garmin 920 XT device. The purpose of this investigation was to assess the accuracy of RR time series measurements from a Garmin 920 XT HRM as compared to a standard ECG, and to verify whether the measurements thus obtained are suitable for HRV analysis. RR time series were collected simultaneously with an ECG (Powerlab system, AD Instruments, Castell Hill, Australia) and a Garmin XT 920 in 11 healthy subjects during three conditions, namely in the supine position, the standing position and during moderate exercise. In a first step, we compared RR time series obtained with both tools using the Bland and Altman method to obtain the limits of agreement in all three conditions. In a second step, we compared the results of HRV analysis between the ECG RR time series and Garmin 920 XT series. Results show that the accuracy of this system is in accordance with the literature in terms of the limits of agreement. In the supine position, bias was 0.01, - 2.24, + 2.26 ms; in the standing position, - 0.01, - 3.12, + 3.11 ms respectively, and during exercise, - 0.01, - 4.43 and + 4.40 ms. Regarding HRV analysis, we did not find any difference for HRV analysis in the supine position, but the standing and exercise conditions both showed small modifications.

  19. CLIPS on the NeXT computer

    NASA Technical Reports Server (NTRS)

    Charnock, Elizabeth; Eng, Norman

    1990-01-01

    This paper discusses the integration of CLIPS into a hybrid expert system neural network AI tool for the NeXT computer. The main discussion is devoted to the joining of these two AI paradigms in a mutually beneficial relationship. We conclude that expert systems and neural networks should not be considered as competing AI implementation methods, but rather as complimentary components of a whole.

  20. Structural transition in Mg-doped LiMn 2O 4: a comparison with other M-doped Li-Mn spinels

    NASA Astrophysics Data System (ADS)

    Capsoni, Doretta; Bini, Marcella; Chiodelli, Gaetano; Massarotti, Vincenzo; Mozzati, Maria Cristina; Azzoni, Carlo B.

    2003-01-01

    The charge distribution in the Mg-doped lithium manganese spinel Li 1.02Mg xMn 1.98- xO 4 with 0.00< x≤0.20 is discussed and compared to those pertinent to other M-doped samples (M=Ni 2+, Co 3+, Cr 3+, Al 3+ and Ga 3+). EPR spectra, low temperature X-ray diffraction and conductivity data are related to the cooperative Jahn-Teller (J-T) transition occurring at about 280 K in the undoped sample. The sensitivity of the cationic sublattice in displaying electronic and magnetic changes after substitution is remarked. The inhibition of the J-T transition is related to the ratio r=|Mn 4+|/|Mn 3+| as deduced from the charge distribution model [Li 1- xt+Mg xt2+] tetr[Li y+ xt+Mg xo2+Mn 1-3 y-2 x3+Mn 1+2 y+ x4+] octa where x= xo+ xt. For y=0.02 and x=0.02, a value r=1.177 is obtained, very close to rlim=1.18, the limit value beyond which the transition is inhibited.

  1. The neXtProt peptide uniqueness checker: a tool for the proteomics community.

    PubMed

    Schaeffer, Mathieu; Gateau, Alain; Teixeira, Daniel; Michel, Pierre-André; Zahn-Zabal, Monique; Lane, Lydie

    2017-11-01

    The neXtProt peptide uniqueness checker allows scientists to define which peptides can be used to validate the existence of human proteins, i.e. map uniquely versus multiply to human protein sequences taking into account isobaric substitutions, alternative splicing and single amino acid variants. The pepx program is available at https://github.com/calipho-sib/pepx and can be launched from the command line or through a cgi web interface. Indexing requires a sequence file in FASTA format. The peptide uniqueness checker tool is freely available on the web at https://www.nextprot.org/tools/peptide-uniqueness-checker and from the neXtProt API at https://api.nextprot.org/. lydie.lane@sib.swiss. © The Author(s) 2017. Published by Oxford University Press.

  2. Enamel shear bond strength of two orthodontic self-etching bonding systems compared to Transbond™ XT.

    PubMed

    Hellak, Andreas; Rusdea, Patrick; Schauseil, Michael; Stein, Steffen; Korbmacher-Steiner, Heike Maria

    2016-11-01

    The aim of this in vitro study was to compare the shear bond strength (SBS) and Adhesive Remnant Index (ARI) scores of two self-etching no-mix adhesives (Prompt L-Pop™ and Scotchbond™) for orthodontic appliances to the commonly used total etch system Transbond XT™ (in combination with phosphoric acid). In all, 60 human premolars were randomly divided into three groups of 20 specimens each. In group 1 (control), brackets were bonded with Transbond™ XT primer. Prompt L-Pop™ (group 2) and Scotchbond™ Universal (group 3) were used in the experimental groups. Lower premolar brackets were bonded by light curing the adhesive. After 24 h of storage, the shear bond strength (SBS) was measured using a Zwicki 1120 testing machine. The adhesive remnant index (ARI) was determined under 10× magnification. The Kruskal-Wallis test was used to statistically compare the SBS and the ARI scores. No significant differences in the SBS between any of the experimental groups were detected (group 1: 15.49 ± 3.28 MPa; group 2: 13.89 ± 4.95 MPa; group 3: 14.35 ± 3.56 MPa; p = 0.489), nor were there any significant differences in the ARI scores (p = 0.368). Using the two self-etching no-mix adhesives (Prompt L-Pop™ and Scotchbond™) for orthodontic appliances does not affect either the SBS or ARI scores in comparison with the commonly used total-etch system Transbond™ XT. In addition, Scotchbond™ Universal supports bonding on all types of surfaces (enamel, metal, composite, and porcelain) with no need for additional primers. It might therefore be helpful for simplifying bonding in orthodontic procedures.

  3. Nonlinear Filtering and Approximation Techniques

    DTIC Science & Technology

    1991-09-01

    filtering. UNIT8 Q RECERCE**No 1223 Programme 5 A utomatique, Productique, Traitement dui Signal et des Donnc~es CONSISTENT PARAMETER ESTIMATION FOR...ue’e[71 E C 2.’(Rm x [0,7]; R) is the unique solution of the Hamilton-Jacobi-Bellman equation 9u,’[7](x, t) - EAu "’[ 7](x,t) + He,’[ 7](x,t,Du,[ 7](x,t

  4. Apple founder targets healthcare as NeXT market. Interview by Carolyn Dunbar and Michael L. Laughlin.

    PubMed

    Jobs, S

    1992-12-01

    Cofounder and former chairman of the board of Apple Computer Steven Jobs looks beyond the 1980s image of a petulant, embittered young man, fighting with all who failed to share his vision, and many who did. Today, as a founder, president and chairman of NeXT, Inc., he looks to more high-minded applications of his computer genius.

  5. Impact of rheology on probabilistic forecasts of sea ice trajectories: application for search and rescue operations in the Arctic

    NASA Astrophysics Data System (ADS)

    Rabatel, Matthias; Rampal, Pierre; Carrassi, Alberto; Bertino, Laurent; Jones, Christopher K. R. T.

    2018-03-01

    We present a sensitivity analysis and discuss the probabilistic forecast capabilities of the novel sea ice model neXtSIM used in hindcast mode. The study pertains to the response of the model to the uncertainty on winds using probabilistic forecasts of ice trajectories. neXtSIM is a continuous Lagrangian numerical model that uses an elasto-brittle rheology to simulate the ice response to external forces. The sensitivity analysis is based on a Monte Carlo sampling of 12 members. The response of the model to the uncertainties is evaluated in terms of simulated ice drift distances from their initial positions, and from the mean position of the ensemble, over the mid-term forecast horizon of 10 days. The simulated ice drift is decomposed into advective and diffusive parts that are characterised separately both spatially and temporally and compared to what is obtained with a free-drift model, that is, when the ice rheology does not play any role in the modelled physics of the ice. The seasonal variability of the model sensitivity is presented and shows the role of the ice compactness and rheology in the ice drift response at both local and regional scales in the Arctic. Indeed, the ice drift simulated by neXtSIM in summer is close to the one obtained with the free-drift model, while the more compact and solid ice pack shows a significantly different mechanical and drift behaviour in winter. For the winter period analysed in this study, we also show that, in contrast to the free-drift model, neXtSIM reproduces the sea ice Lagrangian diffusion regimes as found from observed trajectories. The forecast capability of neXtSIM is also evaluated using a large set of real buoy's trajectories and compared to the capability of the free-drift model. We found that neXtSIM performs significantly better in simulating sea ice drift, both in terms of forecast error and as a tool to assist search and rescue operations, although the sources of uncertainties assumed for the present experiment are not sufficient for complete coverage of the observed IABP positions.

  6. A comparison of shear bond strength of orthodontic brackets bonded with four different orthodontic adhesives

    PubMed Central

    Sharma, Sudhir; Tandon, Pradeep; Nagar, Amit; Singh, Gyan P; Singh, Alka; Chugh, Vinay K

    2014-01-01

    Objectives: The objective of this study is to compare the shear bond strength (SBS) of stainless steel (SS) orthodontic brackets bonded with four different orthodontic adhesives. Materials and Methods: Eighty newly extracted premolars were bonded to 0.022 SS brackets (Ormco, Scafati, Italy) and equally divided into four groups based on adhesive used: (1) Rely-a-Bond (self-cure adhesive, Reliance Orthodontic Product, Inc., Illinois, USA), (2) Transbond XT (light-cure adhesive, 3M Unitek, CA, USA), (3) Transbond Plus (sixth generation self-etch primer, 3M Unitek, CA, USA) with Transbond XT (4) Xeno V (seventh generation self-etch primer, Dentsply, Konstanz, Germany) with Xeno Ortho (light-cure adhesive, Dentsply, Konstanz, Germany) adhesive. Brackets were debonded with a universal testing machine (Model No. 3382 Instron Corp., Canton, Mass, USA). The adhesive remnant index (ARI) was recordedIn addition, the conditioned enamel surfaces were observed under a scanning electron microscope (SEM). Results: Transbond XT (15.49 MPa) attained the highest bond strength. Self-etching adhesives (Xeno V, 13.51 MPa; Transbond Plus, 11.57 MPa) showed clinically acceptable SBS values and almost clean enamel surface after debonding. The analysis of variance (F = 11.85, P < 0.0001) and Chi-square (χ2 = 18.16, P < 0.05) tests revealed significant differences among groups. The ARI score of 3 (i.e., All adhesives left on the tooth) to be the most prevalent in Transbond XT (40%), followed by Rely-a-Bond (30%), Transbond Plus with Transbond XT (15%), and Xeno V with Xeno Ortho (10%). Under SEM, enamel surfaces after debonding of the brackets appeared porous when an acid-etching process was performed on the surfaces of Rely-a-Bond and Transbond XT, whereas with self-etching primers enamel presented smooth and almost clean surfaces (Transbond Plus and Xeno V group). Conclusion: All adhesives yielded SBS values higher than the recommended bond strength (5.9-7–8 MPa), Seventh generation self-etching primer Xeno V with Xeno Ortho showed clinically acceptable SBS and the least amount of residual adhesive left on the enamel surface after debonding. PMID:24987660

  7. Design Model for the Heat Transfer in a Short Straight Tube Boiler.

    DTIC Science & Technology

    1981-06-01

    Equilibrium Quality XT - True Quality XTT - Martinelli Parameter Dimensionless Groups Nu - Nusselt Number Pr - Prandtl Number Re - Reynolds Number...fill a cylinder in which a piston was mounted. When the steam was suddenly condensed by a spray of water, a partial vacuum was created, and the piston...BOILER - 1725 SFET YAL OOS _ FIGURE 6: JAMES WATTS WAGON-TYPE BOILER - 1785 25 water-inlet, a condensate return, a steam outlet, a gauge glass for

  8. Zonal Rate Model for Axial and Radial Flow Membrane Chromatography. Part I: Knowledge Transfer Across Operating Conditions and Scales

    PubMed Central

    Ghosh, Pranay; Vahedipour, Kaveh; Lin, Min; Vogel, Jens H; Haynes, Charles A; von Lieres, Eric

    2013-01-01

    The zonal rate model (ZRM) has previously been applied for analyzing the performance of axial flow membrane chromatography capsules by independently determining the impacts of flow and binding related non-idealities on measured breakthrough curves. In the present study, the ZRM is extended to radial flow configurations, which are commonly used at larger scales. The axial flow XT5 capsule and the radial flow XT140 capsule from Pall are rigorously analyzed under binding and non-binding conditions with bovine serum albumin (BSA) as test molecule. The binding data of this molecule is much better reproduced by the spreading model, which hypothesizes different binding orientations, than by the well-known Langmuir model. Moreover, a revised cleaning protocol with NaCl instead of NaOH and minimizing the storage time has been identified as most critical for quantitatively reproducing the measured breakthrough curves. The internal geometry of both capsules is visualized by magnetic resonance imaging (MRI). The flow in the external hold-up volumes of the XT140 capsule was found to be more homogeneous as in the previously studied XT5 capsule. An attempt for model-based scale-up was apparently impeded by irregular pleat structures in the used XT140 capsule, which might lead to local variations in the linear velocity through the membrane stack. However, the presented approach is universal and can be applied to different capsules. The ZRM is shown to potentially help save valuable material and time, as the experiments required for model calibration are much cheaper than the predicted large-scale experiment at binding conditions. Biotechnol. Bioeng. 2013; 110: 1129–1141. © 2012 Wiley Periodicals, Inc. PMID:23097218

  9. Evaluation and improvement of sticky traps as monitoring tools for Glossina austeni and G. brevipalpis (Diptera: Glossinidae) in north-eastern KwaZulu-Natal, South Africa.

    PubMed

    Green, K Kappmeier; Venter, G J

    2007-12-01

    The attractiveness of various colours, colour combinations and sizes of sticky traps of the 3-dimensional trap (3DT), cross-shaped target (XT), rectangular screen (RT) and monopanels were evaluated for their efficacy to capture Glossina austeni Newstead and G. brevipalpis Newstead in north-eastern KwaZulu-Natal, South Africa. The 3-dimensional shapes of the XT and 3DT in light blue (l.blue) and white were significantly (ca. 3.1-6.9 times) better than the RT for G. austeni. On bicoloured XTs, G. austeni landed preferentially on electric blue (e.blue) (58%) and black (63%) surfaces when used with white; while for G. brevipalpis, significantly more landed on e.blue (60-66%) surfaces when used with l.blue, black or white surfaces. Increased trap size increased the catches of G. brevipalpis females and both sexes of G. austeni significantly. Temoocid and polybutene sticky materials were equally effective and remained durable for 2-3 weeks. The glossy shine of trap surfaces did not have any significant effect on the attraction and landing responses of the two species. The overall trap efficiency of the e.blue/l.blue XT was 23% for G. brevipalpis and 28% for G. austeni, and that of the e.blue/black XT was 16% for G. brevipalpis and 51% for G. austeni. Larger monopanels, painted e.blue/black on both sides, increased the catches of G. austeni females significantly by up to four times compared to the standard e.blue/black XT. This monopanel would be recommended for use as a simple and cost effective survey tool for both species in South Africa.

  10. Novel nano-particles as fillers for an experimental resin-based restorative material.

    PubMed

    Rüttermann, S; Wandrey, C; Raab, W H-M; Janda, R

    2008-11-01

    The purpose of this study is to compare the properties of two experimental materials, nano-material (Nano) and Microhybrid, and two trade products, Clearfil AP-X and Filtek Supreme XT. The flexural strength and modulus after 24h water storage and 5000 thermocycles, water sorption, solubility and X-ray opacity were determined according to ISO 4049. The volumetric behavior (DeltaV) after curing and after water storage was investigated with the Archimedes principle. ANOVA was calculated with p<0.05. Clearfil AP-X showed the highest flexural strength (154+/-14 MPa) and flexural modulus (11,600+/-550 MPa) prior to and after thermocycling (117+/-14 MPa and 13,000+/-300 MPa). The flexural strength of all materials decreased after thermocycling, but the flexural modulus decreased only for Filtek Supreme XT. After thermocycling, there were no significant differences in flexural strength and modulus between Filtek Supreme XT, Microhybrid and Nano. Clearfil AP-X had the lowest water sorption (22+/-1.1 microg mm(-3)) and Nano had the highest water sorption (82+/-2.6 microg mm(-3)) and solubility (27+/-2.9 microg mm(-3)) of all the materials. No significant differences occurred between the solubility of Clearfil AP-X, Filtek Supreme XT and Microhybrid. Microhybrid and Nano provided the highest X-ray opacity. Owing to the lower filler content, Nano showed higher shrinkage than the commercial materials. Nano had the highest expansion after water storage. After thermocycling, Nano performed as well as Filtek Supreme XT for flexural strength, even better for X-ray opacity but significantly worse for flexural modulus, water sorption and solubility. The performances of microhybrids were superior to those of the nano-materials.

  11. Effect of blood and saliva contamination on bond strength of brackets bonded with a protective liquid polish and a light-cured adhesive.

    PubMed

    Sayinsu, Korkmaz; Isik, Fulya; Sezen, Serdar; Aydemir, Bulent

    2007-03-01

    The application of a polymer coating to the labial enamel tooth surface before bonding can help keep white spot lesions from forming. Previous studies evaluating the effects of blood and saliva contamination on the bond strengths of light-cured composites showed significant reductions in bond strength values. The purpose of this study was to investigate whether the bond strength of a light-cured system (Transbond XT, 3M Unitek, Puchheim, Germany) used with a liquid polish (BisCover, Bisco, Schaumburg, Ill) is affected by contamination with blood or saliva. One hundred twenty permanent human premolars were randomly divided into 6 groups of 20. Various enamel surface conditions were studied: dry, blood contaminated, and saliva contaminated. A light-cured bonding system (Transbond XT) was used in all groups. The teeth in group 1 were bonded with Transbond XT. In the second group, BisCover polymeric resin polish was applied on the etched tooth surfaces before the brackets were bonded with Transbond XT resin. Comparison of the first and second groups showed no statistically significant difference. Groups 3 through 6 were bonded without Transbond XT. For groups 3 and 5, a layer of blood or saliva, respectively, was applied to the etched enamel followed by BisCover. In groups 4 and 6, blood or saliva, respectively, was applied on the light-cured BisCover. Shear forces were applied to the samples with a universal testing machine, and bond strengths were measured in megapascals. The protective liquid polish (BisCover) layer did not affect bond strength. Blood contamination on acid-etched surfaces affects bond strength more than saliva contamination. When a protective liquid polish (BisCover) is applied to the tooth surface, the effect of contamination by blood or saliva is prevented.

  12. Genetic Analysis of Hedgehog Signaling in Ventral Body Wall Development and the Onset of Omphalocele Formation

    PubMed Central

    Matsumaru, Daisuke; Haraguchi, Ryuma; Miyagawa, Shinichi; Motoyama, Jun; Nakagata, Naomi; Meijlink, Frits; Yamada, Gen

    2011-01-01

    Background An omphalocele is one of the major ventral body wall malformations and is characterized by abnormally herniated viscera from the body trunk. It has been frequently found to be associated with other structural malformations, such as genitourinary malformations and digit abnormalities. In spite of its clinical importance, the etiology of omphalocele formation is still controversial. Hedgehog (Hh) signaling is one of the essential growth factor signaling pathways involved in the formation of the limbs and urogenital system. However, the relationship between Hh signaling and ventral body wall formation remains unclear. Methodology/Principal Findings To gain insight into the roles of Hh signaling in ventral body wall formation and its malformation, we analyzed phenotypes of mouse mutants of Sonic hedgehog (Shh), GLI-Kruppel family member 3 (Gli3) and Aristaless-like homeobox 4 (Alx4). Introduction of additional Alx4Lst mutations into the Gli3Xt/Xt background resulted in various degrees of severe omphalocele and pubic diastasis. In addition, loss of a single Shh allele restored the omphalocele and pubic symphysis of Gli3Xt/+; Alx4Lst/Lst embryos. We also observed ectopic Hh activity in the ventral body wall region of Gli3Xt/Xt embryos. Moreover, tamoxifen-inducible gain-of-function experiments to induce ectopic Hh signaling revealed Hh signal dose-dependent formation of omphaloceles. Conclusions/Significance We suggest that one of the possible causes of omphalocele and pubic diastasis is ectopically-induced Hh signaling. To our knowledge, this would be the first demonstration of the involvement of Hh signaling in ventral body wall malformation and the genetic rescue of omphalocele phenotypes. PMID:21283718

  13. Long-time behavior for suspension bridge equations with time delay

    NASA Astrophysics Data System (ADS)

    Park, Sun-Hye

    2018-04-01

    In this paper, we consider suspension bridge equations with time delay of the form u_{tt}(x,t) + Δ ^2 u (x,t) + k u^+ (x,t) + a_0 u_t (x,t) + a_1 u_t (x, t- τ ) + f(u(x,t)) = g(x). Many researchers have studied well-posedness, decay rates of energy, and existence of attractors for suspension bridge equations without delay effects. But, as far as we know, there is no work about suspension equations with time delay. In addition, there are not many studies on attractors for other delayed systems. Thus we first provide well-posedness for suspension equations with time delay. And then show the existence of global attractors and the finite dimensionality of the attractors by establishing energy functionals which are related to the norm of the phase space to our problem.

  14. INNOVATIVE TECHNOLOGY VERIFICATION REPORT XRF ...

    EPA Pesticide Factsheets

    The Innov-X XT400 Series (XT400) x-ray fluorescence (XRF) analyzer was demonstrated under the U.S. Environmental Protection Agency (EPA) Superfund Innovative Technology Evaluation (SITE) Program. The field portion of the demonstration was conducted in January 2005 at the Kennedy Athletic, Recreational and Social Park (KARS) at Kennedy Space Center on Merritt Island, Florida. The demonstration was designed to collect reliable performance and cost data for the XT400 analyzer and seven other commercially available XRF instruments for measuring trace elements in soil and sediment. The performance and cost data were evaluated to document the relative performance of each XRF instrument. This innovative technology verification report describes the objectives and the results of that evaluation and serves to verify the performance and cost of the XT400 analyzer. Separate reports have been prepared for the other XRF instruments that were evaluated as part of the demonstration. The objectives of the evaluation included determining each XRF instrument’s accuracy, precision, sample throughput, and tendency for matrix effects. To fulfill these objectives, the field demonstration incorporated the analysis of 326 prepared samples of soil and sediment that contained 13 target elements. The prepared samples included blends of environmental samples from nine different sample collection sites as well as spiked samples with certified element concentrations. Accuracy was as

  15. Biocompatibility of orthodontic adhesives in rat subcutaneous tissue

    PubMed Central

    dos SANTOS, Rogério Lacerda; PITHON, Matheus Melo; FERNANDES, Alline Birra Nolasco; CABRAL, Márcia Grillo; RUELLAS, Antônio Carlos de Oliveira

    2010-01-01

    Objective The objective of the present study was to verify the hypothesis that no difference in biocompatibility exists between different orthodontic adhesives. Material and Methods Thirty male Wistar rats were used in this study and divided into five groups (n=6): Group 1 (control, distilled water), Group 2 (Concise), Group 3 (Xeno III), Group 4 (Transbond XT), and Group 5 (Transbond plus Self-Etching Primer). Two cavities were performed in the subcutaneous dorsum of each animal to place a polyvinyl sponge soaked with 2 drops of the respective adhesive in each surgical loci. Two animals of each group were sacrificed after 7, 15, and 30 days, and their tissues were analyzed by using an optical microscope. Results At day 7, Groups 3 (Transbond XT) and 4 (Xeno III) showed intense mono- and polymorphonuclear inflammatory infiltrate with no differences between them, whereas Groups 1 (control) and 2 (Concise) showed moderate mononuclear inflammatory infiltrate. At day 15, severe inflammation was observed in Group 3 (Transbond XT) compared to other groups. At day 30, the same group showed a more expressive mononuclear inflammatory infiltrate compared to other groups. Conclusion Among the orthodontic adhesive analyzed, it may be concluded that Transbond XT exhibited the worst biocompatibility. However, one cannot interpret the specificity of the data generated in vivo animal models as a human response. PMID:21085807

  16. Statistical Analysis in Dental Research Papers.

    DTIC Science & Technology

    1983-08-08

    AD A136, 019 STATISTICAL ANALYSS IN DENTAL RESEARCH PAPERS(Ul ARMY I INS OF DENTAL NESEARCH WASHINGTON DC L LORTON 0R AUG983 UNCL ASS FED F/S 6/5 IEE...BEFORE COSTL’,..G FORM 2. GOVT ACCESSION NO 3. RECIPIENTS CATALOG NUbER d Ste S. TYPE OF REPORT A PERIOD COVERED ,cistical Analysis in Dental Research ...Papers Submission of papaer Jan- Aue 1983 X!t AUTHOR(&) ". COTACO.RATN Lewis Lorton 9. PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM ELEMENT

  17. Thermal method for cleaning polymer quenching media

    NASA Astrophysics Data System (ADS)

    Sverdlin, A. V.; Blackwood, R.; Totten, G. E.

    1996-06-01

    Aqueous solutions of polymers are used for heat treatment, mainly for quenching steels. The most popular and universally used are quenching liquids of the UCON A, E, XT types based on various polyalkylene glycols. In the course of operation these liquids are contaminated by salts retained on the surface of the parts after their heating in salt baths, by ions of heavy metals present in the solution, etc. The paper is devoted to the most popular method for cleaning polymer quenching media, namely, the method of thermal separation.

  18. Treating childhood intermittent distance exotropia: a qualitative study of decision making.

    PubMed

    Lecouturier, Jan; Clarke, Michael P; Errington, Gail; Hallowell, Nina; Murtagh, Madeleine J; Thomson, Richard

    2015-08-22

    Engaging patients (parents/families) in treatment decisions is increasingly recognised as important and beneficial. Yet where the evidence base for treatment options is limited, as with intermittent distance exotropia (X(T)), this presents a challenge for families and clinicians. The purpose of this study was to explore how decisions are made in the management and treatment of X(T) and what can be done to support decision-making for clinicians, parents and children. This was a qualitative study using face to face interviews with consultant ophthalmologists and orthoptists, and parents of children with X(T). Interview data were analysed using the constant comparative method. The drivers for clinicians in treatment decision-making for X(T) were the proportion of time the strabismus is manifest and parents' views. For parents, decisions were influenced by: fear of bullying and, to a lesser degree, concerns around the impact of the strabismus on their child's vision. Uncertainty around the effectiveness of treatment options caused difficulties for some clinicians when communicating with parents. Parental understanding of the nature of X(T) and rationale for treatment often differed from that of the clinicians, and this affected their involvement in decision-making. Though there were good examples of shared decision-making and parent and child engagement some parents said the process felt rushed and they felt excluded. Parents reported that clinicians provided sufficient information in consultations but they had difficulties in retaining verbal information to convey to other family members. Overall parents were happy with the care their child received but there is scope for better parent and (where appropriate) child engagement in decision-making. There was an expressed need for written information about X(T) to reinforce what was given verbally in consultations and to share with other family members. Access could be via the hospital website, along with videos or blogs from parents and children who have undergone the various management options. A method of assisting clinicians to explain the treatment options, together with the uncertainties, in a clear and concise way could be of particular benefit to orthoptists who have the most regular contact with parents and children, and are more likely to suggest conservative treatments such as occlusion and minus lenses.

  19. New superfield extension of Boussinesq and its (x,t) interchanged equation from odd Poisson bracket

    NASA Astrophysics Data System (ADS)

    Palit, S.; Chowdhury, A. Roy

    1995-08-01

    A new superfield extension of the Boussinesq equation and its corresponding (x,t) interchanged variant are deduced from the odd Poisson-bracket-formalism, which is similar to the antibracket of Batalin and Vilkovisky. In the former case we obtain the equation deduced by Figueroa-O'Farrill et al from a different approach. In each case we have deduced the bi-Hamiltonian structure and some basic symmetries associated with them.

  20. Effect of Nanoscale Fillers on the Local Mechanical Behavior of Polymer Nanocomposites

    DTIC Science & Technology

    2009-12-01

    the interparticle spacing can be related to the particle volume fraction, vp, and the particle diameter, d, by [2] r = d 6v„ d) I I (b) Figure...VGCNFs), namely as- fabricated (PR-24-XT PS), high temperature hear treated (PR-24-XT-HHT-LD), and high temperature hear treated and oxidatively...Therefore, hear treatment had a severe effect on the fracture toughness of composites with embedded VGCNFs. This agrees with composite level

  1. Transcatheter Heart Valve Selection and Permanent Pacemaker Implantation in Patients With Pre-Existent Right Bundle Branch Block.

    PubMed

    van Gils, Lennart; Tchetche, Didier; Lhermusier, Thibault; Abawi, Masieh; Dumonteil, Nicolas; Rodriguez Olivares, Ramón; Molina-Martin de Nicolas, Javier; Stella, Pieter R; Carrié, Didier; De Jaegere, Peter P; Van Mieghem, Nicolas M

    2017-03-03

    Right bundle branch block is an established predictor for new conduction disturbances and need for a permanent pacemaker (PPM) after transcatheter aortic valve replacement. The aim of the study was to evaluate the absolute rates of transcatheter aortic valve replacement related PPM implantations in patients with pre-existent right bundle branch block and categorize for different transcatheter heart valves. We pooled data on 306 transcatheter aortic valve replacement patients from 4 high-volume centers in Europe and selected those with right bundle branch block at baseline without a previously implanted PPM. Logistic regression was used to evaluate whether PPM rate differed among transcatheter heart valves after adjustment for confounders. Mean age was 83±7 years and 63% were male. Median Society of Thoracic Surgeons score was 6.3 (interquartile range, 4.1-10.2). The following transcatheter valve designs were used: Medtronic CoreValve (n=130; Medtronic, Minneapolis, MN); Edwards Sapien XT (ES-XT; n=124) and Edwards Sapien 3 (ES-3; n=32; Edwards Lifesciences, Irvine, CA); and Boston Scientific Lotus (n=20; Boston Scientific Corporation, Marlborough, MA). Overall permanent pacemaker implantation rate post-transcatheter aortic valve replacement was 41%, and per valve design: 75% with Lotus, 46% with CoreValve, 32% with ES-XT, and 34% with ES-3. The indication for PPM implantation was total atrioventricular block in 98% of the cases. Lotus was associated with a higher PPM rate than all other valves. PPM rate did not differ between ES-XT and ES-3. Ventricular paced rhythm at 30-day and 1-year follow-up was present in 81% at 89%, respectively. Right bundle branch block at baseline is associated with a high incidence of PPM implantation for all transcatheter heart valves. PPM rate was highest for Lotus and lowest for ES-XT and ES-3. Pacemaker dependency remained high during follow-up. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  2. Compressed sensing for high-resolution nonlipid suppressed 1 H FID MRSI of the human brain at 9.4T.

    PubMed

    Nassirpour, Sahar; Chang, Paul; Avdievitch, Nikolai; Henning, Anke

    2018-04-29

    The aim of this study was to apply compressed sensing to accelerate the acquisition of high resolution metabolite maps of the human brain using a nonlipid suppressed ultra-short TR and TE 1 H FID MRSI sequence at 9.4T. X-t sparse compressed sensing reconstruction was optimized for nonlipid suppressed 1 H FID MRSI data. Coil-by-coil x-t sparse reconstruction was compared with SENSE x-t sparse and low rank reconstruction. The effect of matrix size and spatial resolution on the achievable acceleration factor was studied. Finally, in vivo metabolite maps with different acceleration factors of 2, 4, 5, and 10 were acquired and compared. Coil-by-coil x-t sparse compressed sensing reconstruction was not able to reliably recover the nonlipid suppressed data, rather a combination of parallel and sparse reconstruction was necessary (SENSE x-t sparse). For acceleration factors of up to 5, both the low-rank and the compressed sensing methods were able to reconstruct the data comparably well (root mean squared errors [RMSEs] ≤ 10.5% for Cre). However, the reconstruction time of the low rank algorithm was drastically longer than compressed sensing. Using the optimized compressed sensing reconstruction, acceleration factors of 4 or 5 could be reached for the MRSI data with a matrix size of 64 × 64. For lower spatial resolutions, an acceleration factor of up to R∼4 was successfully achieved. By tailoring the reconstruction scheme to the nonlipid suppressed data through parameter optimization and performance evaluation, we present high resolution (97 µL voxel size) accelerated in vivo metabolite maps of the human brain acquired at 9.4T within scan times of 3 to 3.75 min. © 2018 International Society for Magnetic Resonance in Medicine.

  3. Performance Assessment of the Spare Parts for the Activation of Relocated Systems (SPARES) Forecasting Model

    DTIC Science & Technology

    1991-09-01

    constant data into the gaining base’s computer records. Among the data elements to be loaded, the 1XT434 image contains the level detail effective date...the mission support effective date, and the PBR override (19:19-203). In conjunction with the 1XT434, the Mission Change Parameter Image (Constant...the gaining base (19:19-208). The level detail effective date establishes the date the MCDDFR and MCDDR "are considered by the requirements computation

  4. Engineering PFLOTRAN for Scalable Performance on Cray XT and IBM BlueGene Architectures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mills, Richard T; Sripathi, Vamsi K; Mahinthakumar, Gnanamanika

    We describe PFLOTRAN - a code for simulation of coupled hydro-thermal-chemical processes in variably saturated, non-isothermal, porous media - and the approaches we have employed to obtain scalable performance on some of the largest scale supercomputers in the world. We present detailed analyses of I/O and solver performance on Jaguar, the Cray XT5 at Oak Ridge National Laboratory, and Intrepid, the IBM BlueGene/P at Argonne National Laboratory, that have guided our choice of algorithms.

  5. Nonzero solutions of nonlinear integral equations modeling infectious disease

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Williams, L.R.; Leggett, R.W.

    1982-01-01

    Sufficient conditions to insure the existence of periodic solutions to the nonlinear integral equation, x(t) = ..integral../sup t//sub t-tau/f(s,x(s))ds, are given in terms of simple product and product integral inequalities. The equation can be interpreted as a model for the spread of infectious diseases (e.g., gonorrhea or any of the rhinovirus viruses) if x(t) is the proportion of infectives at time t and f(t,x(t)) is the proportion of new infectives per unit time.

  6. Guidewire and microcatheter utilization patterns during antegrade wire escalation in chronic total occlusion percutaneous coronary intervention: Insights from a contemporary multicenter registry.

    PubMed

    Karatasakis, Aris; Tarar, Muhammad Nauman J; Karmpaliotis, Dimitri; Alaswad, Khaldoon; Yeh, Robert W; Jaffer, Farouc A; Wyman, R Michael; Lombardi, William L; Grantham, J Aaron; Kandzari, David E; Lembo, Nicholas J; Moses, Jeffrey W; Kirtane, Ajay J; Parikh, Manish; Garcia, Santiago; Doing, Anthony; Pershad, Ashish; Shah, Alpesh; Patel, Mitul; Bahadorani, John; Shoultz, Charles A; Danek, Barbara A; Thompson, Craig A; Banerjee, Subhash; Brilakis, Emmanouil S

    2017-03-01

    We sought to describe contemporary guidewire and microcatheter utilization for antegrade wire escalation (AWE) during chronic total occlusion (CTO) percutaneous coronary intervention (PCI). Equipment utilization for AWE has been variable and evolving over time. We examined device utilization during 694 AWE attempts in 679 patients performed at 15 experienced US centers between May 2012 and April 2015. Mean age was 65.6 ± 9.7 years, and 85% of the patients were men. Successful wiring occurred in 436 AWE attempts (63%). Final technical and procedural success was 91% and 89%, respectively. The mean number of guidewire types used for AWE was 2.2 ± 1.4. The most frequently used guidewire types were the Pilot 200 (Abbott Vascular, 56% of AWE procedures), Fielder XT (Asahi Intecc, 45%), and the Confianza Pro 12 (Asahi Intecc, 28%). The same guidewires were the ones that most commonly crossed the occlusion: Pilot 200 (36% of successful AWE crossings), Fielder XT (20%), and Confianza Pro 12 (11%). A microcatheter or over-the-wire balloon was used for 81% of AWE attempts; the Corsair microcatheter (Asahi Intecc) was the most commonly used (44%). No significant association was found between guidewire type and incidence of major adverse cardiac events (MACE). Our contemporary, multicenter CTO PCI registry demonstrates that the most commonly used wires for AWE are polymer-jacketed guidewires. "Stiff" and polymer-jacketed guidewires appear to provide high crossing rates without an increase in MACE or perforation, and may thus be considered for upfront use. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  7. Polishing and toothbrushing alters the surface roughness and gloss of composite resins.

    PubMed

    Kamonkhantikul, Krid; Arksornnukit, Mansuang; Takahashi, Hidekazu; Kanehira, Masafumi; Finger, Werner J

    2014-01-01

    This study aimed to investigate the surface roughness and gloss of composite resins after using two polishing systems and toothbrushing. Six composite resins (Durafill VS, Filtek Z250, Filtek Z350 XT, Kalore, Venus Diamond, and Venus Pearl) were evaluated after polishing with two polishing systems (Sof-Lex, Venus Supra) and after toothbrushing up to 40,000 cycles. Surface roughness (Ra) and gloss were determined for each composite resin group (n=6) after silicon carbide paper grinding, polishing, and toothbrushing. Two-way ANOVA indicated significant differences in both Ra and gloss between measuring stages for the composite resins tested, except Venus Pearl, which showed significant differences only in gloss. After polishing, the Filtek Z350 XT, Kalore, and Venus Diamond showed significant increases in Ra, while all composite resin groups except the Filtek Z350 XT and Durafill VS with Sof-Lex showed increases in gloss. After toothbrushing, all composite resin demonstrated increases in Ra and decreases in gloss.

  8. Vector fields and nilpotent Lie algebras

    NASA Technical Reports Server (NTRS)

    Grayson, Matthew; Grossman, Robert

    1987-01-01

    An infinite-dimensional family of flows E is described with the property that the associated dynamical system: x(t) = E(x(t)), where x(0) is a member of the set R to the Nth power, is explicitly integrable in closed form. These flows E are of the form E = E1 + E2, where E1 and E2 are the generators of a nilpotent Lie algebra, which is either free, or satisfies some relations at a point. These flows can then be used to approximate the flows of more general types of dynamical systems.

  9. Some ethical issues regarding xenotransfusion.

    PubMed

    Roux, Françoise A; Saï, Pierre; Deschamps, Jack-Yves

    2007-05-01

    The use of porcine red blood cells has recently been proposed as a possible solution to the shortage of blood for human transfusion. The purpose of this paper is to compare some ethical issues regarding xenotransfusion (XTF) with those relating to xenotransplantation (XT) of organs, tissues and cells. Various ethical concerns and viewpoints relating to XTF are discussed. The main ethical obstacles to XT do not apply to XTF. It is much more ethically acceptable to raise pigs for regular blood collection as it doesn't damage the health of the animal. Porcine endogenous retrovirus infection, the major concern associated with XT, does not apply to XTF, since red blood cells have no DNA and have a very short lifespan. Clinical trials will be possible in humans once XTF has been demonstrated to be effective and harmless in non-human primates. Transgenesis is acceptable for pig blood donors because only a limited number of genes are involved, and these animals will never enter into the livestock gene pool or the food chain. Because the need for blood is less pressing than that for organs, tissues or cells, the use of animal blood for human transfusion is not an absolute necessity. However, it represents a real opportunity. The ability to gain access to an unlimited quantity of blood is a reasonable justification for XTF. Because its technical and ethical hurdles are less stringent, XTF could be the first large-scale clinical application of XT.

  10. Role of TiF4 in Microleakage of Silorane and Methacrylate-based Composite Resins in Class V Cavities.

    PubMed

    Koohpeima, Fatemeh; Sharafeddin, Farahnaz; Jowkar, Zahra; Ahmadzadeh, Samaneh; Mokhtari, Mohammad Javad; Azarian, Babak

    2016-03-01

    This study investigated the effect of TiF4 solution pretreat-ment on microleakage of silorane and nanofilled methacrylate-based composites in class V cavities. Forty-eight intact premolar teeth were randomly allocated to four groups of 12 teeth. Restorative techniques after standard class V tooth preparations were as follows: Group 1, Filtek P90 composite; group 2, Filtek Z350 XT; group 3, TiF4 solution pretreatment and Filtek P90 composite; group 4, TiF4 solution pretreatment and Filtek Z350 XT. After storing the specimens in distilled water at 37°C for 24 hours and followed by immersion of the specimens in a 0.5% basic-fuchsin solution for 24 hours, they were sectioned buccolingually to obtain four surfaces for each specimen for analysis of microleakage using a stereomicroscope. Data analysis was performed using Kruskal-Wallis test to compare the four groups and the Mann-Whitney test for paired comparisons with Statistical Package for the Social Sciences (SPSS) version 17 software. At the enamel margins, microleakage score of the Filtek Z350 XT group was lower than those of the Filtek P90 with and without the application of the TiF4 (p = 0.009 and p = 0.031 respectively). At the dentin margins, groups 3 and 4 (TiF4+Filtek P90 and TiF4+Filtek z350 XT respectively) showed significantly lower microleakage than group 1 (Filtek P90). However, there was no significant difference between other groups (p > 0.05). At the enamel margins, microleakage score of the silorane-based composite was more than that of the nanofilled composite. No significant differences were observed between the other groups. At the dentin margins, for the silorane-based composite restorations, TiF4 solution pretreatment resulted in significantly lower microleakage. However, the similar result was not observed for Filtek Z350 XT. Also, no significant difference was observed between microleakage scores of Filtek P90 and Filtek Z350 XT with or without TiF4 pretreatment. In spite of better mechanical and physical properties of modern composites than earlier methacrylate-based composites, polymerization shrinkage has been remaining as one of the main shortcomings of them. Different methods, such as using new low shrinkage resin composites and different dentin pretreatments, have been suggested to overcome this problem. This study evaluated the effect of TiF4 as pretreatment on microleakage of class V tooth preparations restored with a nanocomposite and a silorane-based resin composite.

  11. On Wave and Entropic Amplitudes in Maxwellian Materials.

    DTIC Science & Technology

    1982-09-01

    drawbacks. Finally, in the last of a major series of papers on the propagation and growth "" behavior of waves in materials with memory, Coleman, Greenberg ...equations to calculate xa T 1C. As in Coleman, Greenberg , and Gurtin [5], we may then replace [at a xT 1 by [ at T]. Now, at all points (X,t) (Y(t),t...behavior of the amplitude, a(t), is based on this fact and the continuity of I(t). Following Coleman, Greenberg , and Gurtin [5] we set (5.8) (t ) -1/I(t ) 0

  12. Accuracy Assessment for the Auxillary Tracking System

    DTIC Science & Technology

    1991-09-01

    Auxiliary Tracking System (ATS), paper prepared for evaluation of ATS design review, 28 June, 1990. Anton , H., and Rorres, C., Elementary Linear Algebra with...are linearized around the trial value (XT6, YT,, Zro), shown in Equation 3.16, where 10 means evaluated at point "o". The OR1aI * YaT- I T.) ZR (ZT...3.16) partial derivatives are listed in Equations 3.17 through 3.19. 8XR.[ o 7.-OR1 [ .XT-XL (3.17) aOR., ZTo-Z 1 (3.19) aZTIo R. The linearized

  13. Military Off-the-Shelf: A Discussion on Combat Ship Acquisition

    DTIC Science & Technology

    2014-08-01

    Layton ...S+ + ‘C le an S he et ’ In te rio r/ e xt er io r d es ig n id en tic al N ea r- id en tic al d es ig n / m in or m od s Si m...ila rit y in d es ig n bu t w ith U ni qu e de si gn a nd to le ad sh ip a to e xt er na l s tru ct ur e , in te rn al sy

  14. Functional Itô versus Banach space stochastic calculus and strict solutions of semilinear path-dependent equations

    NASA Astrophysics Data System (ADS)

    Cosso, Andrea; Russo, Francesco

    2016-11-01

    Functional Itô calculus was introduced in order to expand a functional F(t,Xṡ+t,Xt) depending on time t, past and present values of the process X. Another possibility to expand F(t,Xṡ+t,Xt) consists in considering the path Xṡ+t = {Xx+t,x ∈ [-T, 0]} as an element of the Banach space of continuous functions on C([-T, 0]) and to use Banach space stochastic calculus. The aim of this paper is threefold. (1) To reformulate functional Itô calculus, separating time and past, making use of the regularization procedures which match more naturally the notion of horizontal derivative which is one of the tools of that calculus. (2) To exploit this reformulation in order to discuss the (not obvious) relation between the functional and the Banach space approaches. (3) To study existence and uniqueness of smooth solutions to path-dependent partial differential equations which naturally arise in the study of functional Itô calculus. More precisely, we study a path-dependent equation of Kolmogorov type which is related to the window process of the solution to an Itô stochastic differential equation with path-dependent coefficients. We also study a semilinear version of that equation.

  15. Shear Bond Strength of Three Orthodontic Bonding Systems on Enamel and Restorative Materials

    PubMed Central

    Ebeling, Jennifer; Schauseil, Michael; Stein, Steffen; Roggendorf, Matthias; Korbmacher-Steiner, Heike

    2016-01-01

    Objective. The aim of this in vitro study was to determine the shear bond strength (SBS) and adhesive remnant index (ARI) score of two self-etching no-mix adhesives (iBond™ and Scotchbond™) on different prosthetic surfaces and enamel, in comparison with the commonly used total etch system Transbond XT™. Materials and Methods. A total of 270 surfaces (1 enamel and 8 restorative surfaces, n = 30) were randomly divided into three adhesive groups. In group 1 (control) brackets were bonded with Transbond XT primer. In the experimental groups iBond adhesive (group 2) and Scotchbond Universal adhesive (group 3) were used. The SBS was measured using a Zwicki 1120™ testing machine. The ARI and SBS were compared statistically using the Kruskal–Wallis test (P ≤ 0.05). Results. Significant differences in SBS and ARI were found between the control group and experimental groups. Conclusions. Transbond XT showed the highest SBS on human enamel. Scotchbond Universal on average provides the best bonding on all other types of surface (metal, composite, and porcelain), with no need for additional primers. It might therefore be helpful for simplifying bonding in orthodontic procedures on restorative materials in patients. If metal brackets have to be bonded to a metal surface, the use of a dual-curing resin is recommended. PMID:27738633

  16. Evaluation of the antibacterial activity of a conventional orthodontic composite containing silver/hydroxyapatite nanoparticles.

    PubMed

    Sodagar, Ahmad; Akhavan, Azam; Hashemi, Ehsan; Arab, Sepideh; Pourhajibagher, Maryam; Sodagar, Kosar; Kharrazifard, Mohammad Javad; Bahador, Abbas

    2016-12-01

    One of the most important complications of fixed orthodontic treatment is the formation of white spots which are initial carious lesions. Addition of antimicrobial agents into orthodontic adhesives might be a wise solution for prevention of white spot formation. The aim of this study was to evaluate the antibacterial properties of a conventional orthodontic adhesive containing three different concentrations of silver/hydroxyapatite nanoparticles. One hundred and sixty-two Transbond XT composite discs containing 0, 1, 5, and 10 % silver/hydroxyapatite nanoparticles were prepared and sterilized. Antibacterial properties of these composite groups against Streptococcus mutans, Lactobacillus acidophilus, and Streptococcus sanguinis were investigated using three different antimicrobial tests. Disk agar diffusion test was performed to assess the diffusion of antibacterial agent on brain heart infusion agar plate by measuring bacterial growth inhibition zones. Biofilm inhibition test showed the antibacterial capacity of composite discs against resistant bacterial biofilms. Antimicrobial activity of eluted components from composite discs was investigated by comparing the viable counts of bacteria after 3, 15, and 30 days. Composite discs containing 5 and 10 % silver/hydroxyapatite nanoparticles were capable of producing growth inhibition zones for all bacterial types. Results of biofilm inhibition test showed that all of the study groups reduced viable bacterial count in comparison to the control group. Antimicrobial activity of eluted components from composite discs was immensely diverse based on the bacterial type and the concentration of nanoparticles. Transbond XT composite discs containing 5 and 10 % silver/hydroxyapatite nanoparticles produce bacterial growth inhibition zones and show antibacterial properties against biofilms.

  17. Application of Strep-Tactin XT for affinity purification of Twin-Strep-tagged CB2, a G protein-coupled cannabinoid receptor

    PubMed Central

    Yeliseev, Alexei; Zoubak, Lioudmila; Schmidt, Thomas G.M.

    2017-01-01

    Human cannabinoid receptor CB2 belongs to the class A of G protein-coupled receptor (GPCR). High resolution structural studies of CB2 require milligram quantities of purified, structurally intact protein. Here we describe an efficient protocol for purification of this protein using the Twin-Strep-tag/Strep-Tactin XT system. To improve the affinity of interaction of the recombinant CB2 with the resin, the double repeat of the Strep-tag was attached either to the N- or C-terminus of CB2 via a short linker. The CB2 was isolated at high purity from dilute solutions containing high concentrations of detergents, glycerol and salts, by capturing onto the Strep-Tactin XT resin, and was eluted from the resin under mild conditions upon addition of biotin. Surface plasmon resonance studies performed demonstrate the high affinity of interaction between the Twin-Strep-tag fused to the CB2 and Strep-Tactin XT with an estimated Kd in the low nanomolar range. The affinity of binding did not vary significantly in response to the position of the tag at either N- or C-termini of the fusion. The variation in the length of the linker between the double repeats of the Strep-tag from 6 to 12 amino acid residues did not significantly affect the binding. The novel purification protocol reported here enables efficient isolation of a recombinant GPCR expressed at low titers in host cells. This procedure is suitable for preparation of milligram quantities of stable isotope-labelled receptor for high-resolution NMR studies. PMID:27867058

  18. Xenon ventilation computed tomography and the management of asthma in the elderly.

    PubMed

    Park, Heung-Woo; Jung, Jae-Woo; Kim, Kyung-Mook; Kim, Tae-Wan; Lee, So-Hee; Lee, Chang Hyun; Goo, Jin Mo; Min, Kyung-Up; Cho, Sang-Heon

    2014-04-01

    Xenon ventilation computed tomography (CT) has shown potential in assessing the regional ventilation status in subjects with asthma. The purpose of this study was to evaluate the usefulness of xenon ventilation CT in the management of asthma in the elderly. Treatment-naïve asthmatics aged 65 years or older were recruited. Before initiation of medication, spirometry with bronchodilator (BD) reversibility, questionnaires to assess the severity of symptoms including a visual analogue scale (VAS), tests to evaluate cognitive function and mood, and xenon ventilation CT were performed. Xenon gas trapping (XT) on xenon ventilation CT represents an area where inhaled xenon gas was not expired and was trapped. Symptoms and lung functions were measured again after the 12-week treatment. A total of 30 elderly asthmatics were enrolled. The severity of dyspnoea measured by the VAS showed a significant correlation with the total number of areas of XT on the xenon ventilation CT taken in the pre-BD wash-out phase (r = -0.723, P < 0.001). The total number of areas of XT significantly decreased after BD inhalation, and differences in the total number of areas of XT (between the pre- and post-BD wash-out phases) at baseline showed significant correlations with the per cent increases in forced expiratory volume in 1 s after subsequent anti-asthma treatment (r = -0.775, P < 0.001). Xenon ventilation CT may be an objective and promising tool in the measurement of dyspnoea and prediction of the treatment response in elderly asthmatics. © 2014 The Authors. Respirology © 2014 Asian Pacific Society of Respirology.

  19. Polishing mechanism of light-initiated dental composite: Geometric optics approach.

    PubMed

    Chiang, Yu-Chih; Lai, Eddie Hsiang-Hua; Kunzelmann, Karl-Heinz

    2016-12-01

    For light-initiated dental hybrid composites, reinforcing particles are much stiffer than the matrix, which makes the surface rugged after inadequate polish and favors bacterial adhesion and biofilm redevelopment. The aim of the study was to investigate the polishing mechanism via the geometric optics approach. We defined the polishing abilities of six instruments using the obtained gloss values through the geometric optics approach (micro-Tri-gloss with 20°, 60°, and 85° measurement angles). The surface texture was validated using a field emission scanning electron microscope (FE-SEM). Based on the gloss values, we sorted polishing tools into three abrasive levels, and proposed polishing sequences to test the hypothesis that similar abrasive levels would leave equivalent gloss levels on dental composites. The three proposed, tested polishing sequences included: S1, Sof-Lex XT coarse disc, Sof-Lex XT fine disc, and OccluBrush; S2, Sof-Lex XT coarse disc, Prisma Gloss polishing paste, and OccluBrush; and S3, Sof-Lex XT coarse disc, Enhance finishing cups, and OccluBrush. S1 demonstrated significantly higher surface gloss than the other procedures (p < 0.05). The surface textures (FE-SEM micrographs) correlated well with the obtained gloss values. Nominally similar abrasive abilities did not result in equivalent polish levels, indicating that the polishing tools must be evaluated and cannot be judged based on their compositions or abrasive sizes. The geometric optic approach is an efficient and nondestructive method to characterize the polished surface of dental composites. Copyright © 2015. Published by Elsevier B.V.

  20. Equivalence of interest rate models and lattice gases.

    PubMed

    Pirjol, Dan

    2012-04-01

    We consider the class of short rate interest rate models for which the short rate is proportional to the exponential of a Gaussian Markov process x(t) in the terminal measure r(t)=a(t)exp[x(t)]. These models include the Black-Derman-Toy and Black-Karasinski models in the terminal measure. We show that such interest rate models are equivalent to lattice gases with attractive two-body interaction, V(t(1),t(2))=-Cov[x(t(1)),x(t(2))]. We consider in some detail the Black-Karasinski model with x(t) as an Ornstein-Uhlenbeck process, and show that it is similar to a lattice gas model considered by Kac and Helfand, with attractive long-range two-body interactions, V(x,y)=-α(e(-γ|x-y|)-e(-γ(x+y))). An explicit solution for the model is given as a sum over the states of the lattice gas, which is used to show that the model has a phase transition similar to that found previously in the Black-Derman-Toy model in the terminal measure.

  1. Effect of the Polishing Procedures on Color Stability and Surface Roughness of Composite Resins

    PubMed Central

    Schmitt, Vera Lucia; Puppin-Rontani, Regina Maria; Naufel, Fabiana Scarparo; Nahsan, Flávia Pardo Salata; Alexandre Coelho Sinhoreti, Mário; Baseggio, Wagner

    2011-01-01

    Objectives. To evaluate the polishing procedures effect on color stability and surface roughness of composite resins. Methods. Specimens were distributed into 6 groups: G1: Filtek Supreme XT + PoGo; G2: Filtek Supreme XT + Sof-Lex; G3: Filtek Supreme XT + no polishing; G4: Amelogen + PoGo; G5: Amelogen + Sof-Lex.; G6: Amelogen + no polishing. Initial color values were evaluated using the CIELab scale. After polishing, surface roughness was evaluated and the specimens were stored in coffee solution at 37°C for 7 days. The final color measurement and roughness were determined. Results. Sof-Lex resulted in lower staining. Amelogen showed the highest roughness values than Filtek Supreme on baseline and final evaluations regardless of the polishing technique. Filtek Supreme polished with PoGo showed the lowest roughness values. All groups presented discoloration after storage in coffee solution, regardless of the polishing technique. Conclusion. Multiple-step polishing technique provided lower degree of discoloration for both composite resins. The final surface texture is material and technique dependent. PMID:21991483

  2. Equivalence of interest rate models and lattice gases

    NASA Astrophysics Data System (ADS)

    Pirjol, Dan

    2012-04-01

    We consider the class of short rate interest rate models for which the short rate is proportional to the exponential of a Gaussian Markov process x(t) in the terminal measure r(t)=a(t)exp[x(t)]. These models include the Black-Derman-Toy and Black-Karasinski models in the terminal measure. We show that such interest rate models are equivalent to lattice gases with attractive two-body interaction, V(t1,t2)=-Cov[x(t1),x(t2)]. We consider in some detail the Black-Karasinski model with x(t) as an Ornstein-Uhlenbeck process, and show that it is similar to a lattice gas model considered by Kac and Helfand, with attractive long-range two-body interactions, V(x,y)=-α(e-γ|x-y|-e-γ(x+y)). An explicit solution for the model is given as a sum over the states of the lattice gas, which is used to show that the model has a phase transition similar to that found previously in the Black-Derman-Toy model in the terminal measure.

  3. Effects of cold light bleaching on the color stability of composite resins

    PubMed Central

    Cao, Liqun; Huang, Lijuan; Wu, Meisheng; Wei, Hua; Zhao, Shouliang

    2015-01-01

    To evaluate the effects of cold light bleaching on the color stability of four restorations using a thermocycling stain challenge. 160 specimens (10 mm in diameter and 2 mm thick) were fabricated from 4 composite resins (Gradia Direct-A, Z350XT, Premisa, and Précis) and divided into 4 subgroups. Color was assessed according to the CIEL*a*b* color scale at baseline, after the first cycle of bleaching, after thermocycling stain challenges, and after the second cycle of bleaching. Mean values were compared using three-way analysis of variance, and multiple comparisons of the mean values were performed using the Tukey-Kramer test. All groups showed significant color changes after stain challenge, the color change was more significant in Gradia Direct and Z350XT than in Premisa and Précis. After the second cycle of bleaching, color mostly recovered to its original values. The color stability of Gradia Direct and Z350XT was inferior to that of Premisa and Précis. The discoloration of composite resin materials can be partly removed after cold light bleaching. PMID:26309549

  4. Comparison of the BD MAX MRSA XT to the Cepheid™ Xpert® MRSA assay for the molecular detection of methicillin-resistant Staphylococcus aureus from nasal swabs.

    PubMed

    Mehta, Sanjay R; Estrada, Jasmine; Ybarra, Juan; Fierer, Joshua

    2017-04-01

    Variation in MRSA genotypes may affect the sensitivity of molecular assays to detect this organism. We compared 2 commonly used screening assays, the Cepheid™ Xpert® MRSA and the BD MAX™ MRSA XT on consecutively obtained nasal swabs from 479 subjects. Specimens giving discordant results were subjected to additional microbiologic and molecular testing. Six hundred forty-two (97.6%) of the 658 test results were concordant. Of the 16 discordant results from 12 subjects, additional results suggested that 9 (60%) of the 15 MRSA XT assays were likely correct, and 6 (40%) of the 15 Xpert® assays were likely correct. One discordant result could not be resolved. A mecA dropout and novel mec right-extremity junction (MREJ) sites led to false-positive and negative results by Xpert®. While both assays performed well, continued vigilance is needed to monitor for Staphylococcus aureus with novel MREJ sites, mecA dropouts, and mecC, leading to inaccurate results in screening assays. Published by Elsevier Inc.

  5. On diagrammatic technique for nonlinear dynamical systems

    NASA Astrophysics Data System (ADS)

    Semenyakin, Mykola

    2014-11-01

    In this paper, we investigate phase flows over ℂn and ℝn generated by vector fields V = ∑ Pi∂i where Pi are finite degree polynomials. With the convenient diagrammatic technique, we get expressions for evolution operators ev{V|t} : x(0) ↦ x(t) through the series in powers of x(0) and t, represented as sum over all trees of a particular type. Estimates are made for the radius of convergence in some particular cases. The phase flows behavior in the neighborhood of vector field fixed points are examined. Resonance cases are considered separately.

  6. Valve-in-valve using an Edwards Sapien XT into a JenaValve in a patient with a low originating left coronary artery and a heavily calcified aorta.

    PubMed

    Fujita, Buntaro; Scholtz, Smita; Ensminger, Stephan

    2016-04-01

    Coronary obstruction during transcatheter aortic valve implantation is a potentially life-threatening complication. Most of the widely used transcatheter heart valves require a certain distance between the basal aortic annular plane and the origins of the coronary arteries. We report the case of a successful valve-in-valve procedure with an Edwards SAPIEN XT valve into a JenaValve as a bail-out procedure in a patient with a low originating left coronary artery and a heavily calcified aorta. © 2015 Wiley Periodicals, Inc.

  7. Comparing dynamic hyperinflation and associated dyspnea induced by metronome-paced tachypnea versus incremental exercise.

    PubMed

    Calligaro, Gregory L; Raine, Richard I; Bateman, Mary E; Bateman, Eric D; Cooper, Christopher B

    2014-02-01

    Dynamic hyperinflation (DH) during exercise is associated with both dyspnea and exercise limitation in COPD. Metronome-paced tachypnoea (MPT) is a simple alternative for studying DH. We compared MPT with exercise testing (XT) as methods of provoking DH, and assessed their relationship with dyspnea. We studied 24 patients with moderate COPD (FEV1 59 ± 9% predicted) after inhalation of ipratropium/salbutamol combination or placebo in a double-blind, crossover design. Inspiratory capacity (IC) was measured at baseline and after 30 seconds of MPT with breathing frequencies (fR) of 20, 30 and 40 breaths/min and metronome-defined I:E ratios of 1:1 and 1:2, in random sequence, followed by incremental cycle ergometry with interval determinations of IC. DH was defined as a decline in IC from baseline (∆IC) for both methods. Dyspnea was assessed using a Borg CR-10 scale. ∆IC during MPT was greater with higher fR and I:E ratio of 1:1 versus 1:2, and less when patients were treated with bronchodilator rather than placebo (P = 0.032). DH occurred during 19 (40%) XTs, and during 35 (73%) tests using MPT. Eleven of 18 (61%) non-congruent XTs (where DH occurred on MPT but not XT) terminated before fR of 40 breaths/min was reached. Although greater during XT, the intensity of dyspnea bore no relationship to DH during either MPT and XT. MPT at 40 breaths/min and I:E of 1:1 elicits the greatest ∆IC, and is a more sensitive method for demonstrating DH. The relationship between DH and dyspnea is complex and not determined by DH alone.

  8. Effect of changes to the manufacturer application techniques 
on the shear bond strength of simplified dental adhesives.

    PubMed

    Chasqueira, Ana Filipa; Arantes-Oliveira, Sofia; Portugal, Jaime

    2013-09-13

    The aim of this work was to assess the shear bond strength (SBS) between a composite resin and dentin, promoted by two dental adhesive systems (one-step self-etching adhesive Easy Bond [3M ESPE], and two-step etch-and-rinse adhesive Scotchbond 1XT [3M ESPE]) with different application protocols (per manufacturer's instruction (control group); with one to four additional adhesive layers; or with an extra hydrophobic adhesive layer). Proximal enamel was removed from ninety caries-free human molars to obtain two dentin discs per tooth, which were randomly assigned to twelve experimental groups (n=15). After adhesion protocol, the composite resin (Filtek Z250 [3M ESPE]) was applied. Specimens were mounted in the Watanabe test device and shear bond test was performed in a universal testing machine with a crosshead speed of 5 mm/min. Data were analyzed with ANOVA followed by Student-Newman-Keuls tests (P<0.05). The highest SBS mean value was attained with the Easy Bond three layers group (41.23±2.71 MPa) and the lowest with Scotchbond 1XT per manufacturer's instructions (27.15±2.99 MPa). Easy Bond yielded higher SBS values than Scotchbond 1XT. There were no statistically significant differences (P>0.05) between the application protocols tested, except for the three and four layers groups, that presented higher SBS results compared to manufacturer's instruction groups (P<0.05). No statistically significant differences were detected between the three and four layers groups (P≥0.05). It is recommendable to apply three adhesive layers when using Easy Bond and Scotchbond 1XT adhesives, since it improves SBS values without consuming much time.

  9. Activity-dependent branching ratios in stocks, solar x-ray flux, and the Bak-Tang-Wiesenfeld sandpile model

    NASA Astrophysics Data System (ADS)

    Martin, Elliot; Shreim, Amer; Paczuski, Maya

    2010-01-01

    We define an activity-dependent branching ratio that allows comparison of different time series Xt . The branching ratio bx is defined as bx=E[ξx/x] . The random variable ξx is the value of the next signal given that the previous one is equal to x , so ξx={Xt+1∣Xt=x} . If bx>1 , the process is on average supercritical when the signal is equal to x , while if bx<1 , it is subcritical. For stock prices we find bx=1 within statistical uncertainty, for all x , consistent with an “efficient market hypothesis.” For stock volumes, solar x-ray flux intensities, and the Bak-Tang-Wiesenfeld (BTW) sandpile model, bx is supercritical for small values of activity and subcritical for the largest ones, indicating a tendency to return to a typical value. For stock volumes this tendency has an approximate power-law behavior. For solar x-ray flux and the BTW model, there is a broad regime of activity where bx≃1 , which we interpret as an indicator of critical behavior. This is true despite different underlying probability distributions for Xt and for ξx . For the BTW model the distribution of ξx is Gaussian, for x sufficiently larger than 1, and its variance grows linearly with x . Hence, the activity in the BTW model obeys a central limit theorem when sampling over past histories. The broad region of activity where bx is close to one disappears once bulk dissipation is introduced in the BTW model—supporting our hypothesis that it is an indicator of criticality.

  10. Corrosion behavior of aluminum-alumina composites in aerated 3.5 percent chloride solution

    NASA Astrophysics Data System (ADS)

    Acevedo Hurtado, Paul Omar

    Aluminum based metal matrix composites are finding many applications in engineering. Of these Al-Al2O3 composites appear to have promise in a number of defense applications because of their mechanical properties. However, their corrosion behavior remains suspect, especially in marine environments. While efforts are being made to improve the corrosion resistance of Al-Al2O3 composites, the mechanism of corrosion is not well known. In this study, the corrosion behavior of powder metallurgy processed Al-Cu alloy reinforced with 10, 15, 20 and 25 vol. % Al2O3 particles (XT 1129, XT 2009, XT 2048, XT 2031) was evaluated in aerated 3.5% NaCl solution using microstructural and electrochemical measurements. AA1100-O and AA2024T4 monolithic alloys were also studied for comparison purposes. The composites and unreinforced alloys were subjected to potentiodynamic polarization and Electrochemical Impedance Spectroscopy (EIS) testing. Addition of 25 vol. % Al2O 3 to the base alloys was found to increase its corrosion resistance considerably. Microstructural studies revealed the presence of intermetallic Al2Cu particles in these composites that appeared to play an important role in the observations. Pitting potential for these composites was near corrosion potential values, and repassivation potential was below the corresponding corrosion potential, indicating that these materials begin to corrode spontaneously as soon as they come in contact with the 3.5 % NaCl solution. EIS measurements indicate the occurrence of adsorption/diffusion phenomena at the interface of the composites which ultimately initiate localized or pitting corrosion. Polarization resistance values were extracted from the EIS data for all the materials tested. Electrically equivalent circuits are proposed to describe and substantiate the corrosive processes occurring in these Al-Al2O 3 composite materials.

  11. Gli3-mediated somitic Fgf10 expression gradients are required for the induction and patterning of mammary epithelium along the embryonic axes.

    PubMed

    Veltmaat, Jacqueline M; Relaix, Frédéric; Le, Lendy T; Kratochwil, Klaus; Sala, Frédéric G; van Veelen, Wendy; Rice, Ritva; Spencer-Dene, Bradley; Mailleux, Arnaud A; Rice, David P; Thiery, Jean Paul; Bellusci, Saverio

    2006-06-01

    Little is known about the regulation of cell fate decisions that lead to the formation of five pairs of mammary placodes in the surface ectoderm of the mouse embryo. We have previously shown that fibroblast growth factor 10 (FGF10) is required for the formation of mammary placodes 1, 2, 3 and 5. Here, we have found that Fgf10 is expressed only in the somites underlying placodes 2 and 3, in gradients across and within these somites. To test whether somitic FGF10 is required for the formation of these two placodes, we analyzed a number of mutants with different perturbations of somitic Fgf10 gradients for the presence of WNT signals and ectodermal multilayering, markers for mammary line and placode formation. The mammary line is displaced dorsally, and formation of placode 3 is impaired in Pax3ILZ/ILZ mutants, which do not form ventral somitic buds. Mammary line formation is impaired and placode 3 is absent in Gli3Xt-J/Xt-J and hypomorphic Fgf10 mutants, in which the somitic Fgf10 gradient is shortened dorsally and less overall Fgf10 is expressed, respectively. Recombinant FGF10 rescued mammogenesis in Fgf10(-/-) and Gli3Xt-J/Xt-J flanks. We correlate increasing levels of somitic FGF10 with progressive maturation of the surface ectoderm, and show that full expression of somitic Fgf10, co-regulated by GLI3, is required for the anteroposterior pattern in which the flank ectoderm acquires a mammary epithelial identity. We propose that the intra-somitic Fgf10 gradient, together with ventral elongation of the somites, determines the correct dorsoventral position of mammary epithelium along the flank.

  12. a Study of High Transition Temperature Superconductors: Mercury-Copper Oxide Systems

    NASA Astrophysics Data System (ADS)

    Kirven, Paul Douglas

    1995-01-01

    The Hg-based copper-oxides viz., HgBa _2Ca_{n-1}Cu_ nO _{2n+2+delta}, were discovered in 1993. A system consisting of many different, but related, compounds can be synthesized by including or substituting one or more elements in the original compound (e.g. Hg _{1-x}Pb_ x). In this thesis, the superconducting and normal state properties of several of these compounds were investigated. In the normal state electrical resistivity rho(T) is a linear function of temperature (T) and the magnetic susceptibility, X(T), is weakly paramagnetic. Many were observed to superconduct at very high temperatures. At 5 K up to 80% perfect diamagnetic X(T) was measured. The onset transition temperature (T_ c), where a specimen starts to superconduct, is observed to be as high as 135 K. Although T_ c is about 10 K higher than that of any previously known material, in many respects the properties of this new system are similar to that of other type II superconductors. Flux flow behavior and the nature of these type II superconductors was investigated via SQUID measurements and high field longitudinal magneto-resistance R(T,H) as a function of field and temperature. The study of flux motion allows one to observe Anderson-Kim type logarithimic flux creep at low temperature and field (T < 80K and B < 2T) and giant -flux flow at high temperature and field (80 < T < 130; B < 17T). Key parameters were determined. Some of which include reversibility temperature T*(H), critical field Hc, and pinning potential, Uo. Normal state properties which were also measured include the following: Curie constant, Curie-Weiss temperature (15-25 K), temperature independent susceptibility, and Sommerfeld constant (10-25 mJ/mol.Cu K^2). The values of these parameters of the Hg-based superconductors were compared to those of other superconductors. The results of this investigation are expected to yield a better understanding of this newest family of high temperature superconductors.

  13. Antioxidative properties of milk protein preparations fermented by Polish strains of Lactobacillus helveticus.

    PubMed

    Skrzypczak, Katarzyna W; Gustaw, Waldemar Z; Jabłońska-Ryś, Ewa D; Michalak-Majewska, Monika; Sławińska, Aneta; Radzki, Wojciech P; Gustaw, Klaudia M; Waśko, Adam D

    2017-01-01

    The increasing significance of food products containing substances with antioxidative activi- ties is currently being observed. This is mainly due to the fact that pathogenic changes underlying some diseases are related to the carcinogenic effects of free radicals. Antioxidative compounds play an important role in supporting and enhancing the body’s defense mechanisms, which is useful in preventing some civili- zation diseases. Unfortunately, it has been already proved that some synthetic antioxidants pose a potential risk in vivo. Therefore, antioxidant compounds derived from a natural source are extremely valuable. Milk is a source of biologically active precursors, which when enclosed in structural protein sequences are inactive. The hydrolysis process, involving bacterial proteolytic enzymes, might release biopeptides that act in various ways, including having antioxidant properties. The objective of this study was to determine the antioxidant properties of milk protein preparations fermented by Polish strains of L. helveticus. The research also focused on evaluating the dynamics of milk acidification by these strains and analyzing the textural properties of the skim milk fermented products obtained. The research studied Polish strains of L. helveticus: B734, 141, T80 and T105, which have not yet been used industrially. The antioxidant properties of 1% (w/v) solutions of milk protein preparations (skim milk powder, caseinoglycomacropeptide and α-lactoalbumin) fermented by these strains were determined by neutralizing the free radicals with 2,2-diphenyl-1-picrylhydrazyl (DPPH˙). Moreover, solutions of skim milk powder (SMP) fermented by the microorganisms being tested were analyzed on gel electrophoresis (SDS-PAGE). The dynamics of milk acidification by these microorganisms was also analyzed L. helveticus strains were used to prepare fermented regenerated skim milk products that were subjected to texture profile analysis (TPA) performed using a TA-XT2i (Stable Micro Systems, Godalming, UK). The results suggest that the antioxidant activity of fermented milk protein preparations depended on the type of milk protein preparation and was also related to the strain that conducted the fermentation process. The process of caseinoglycomacropeptide (CGMP) fermentation by DSMZ 20075, T105 and 141 signifi- cantly (p < 0.05) influenced the increase in the antioxidant activities of the protein preparation, the highest values of parameter were obtained in samples fermented by L. helveticus T105 (64.82 ±0.013%), while in the case of α-lactoalbumin (α-la), the strongest free radical scavenging activity (66.67 ±0.020%) was noted for unfermented samples (control). The greatest increase in DPPH scavenging activity (% of inhibition) was noted for fermented SMP solutions. The highest values of the parameter measured were recorded for SMP fermented by the reference strain (85.98 ±0.009%) and T80 (81.66 ±0.013%). Strain T105 demonstrated the most desirable properties with respect to milk acidifying dynamic and texture properties of fermented skim milk products, while the reference strain (L. helveticus DSMZ 20075) and L. helveticus T80 seem to be more desirable in terms of the possibility of obtaining fermented protein preparations with the best antioxidant properties. The Polish strains analyzed here might find application in dairy products and also in developing functional food products. Furthermore, the preparations of milk protein that were fermented by the strains being tested may be a natural source dietary antioxidants.

  14. Identifiability and Problems of Model Selection for Time-Series Analysis in Econometrics.

    DTIC Science & Technology

    1980-01-01

    Z is defined by (2.1) Fx + ( y( If x(t), T c R;dt for discrete-time, that is, with the time set T = Z = integers, a system F is given by * The...O1/14/81 cb (2.2) x(t + 1) Fx (t) + Gu(t), y(t) = Hx(t), t c Z. In (2.1-2.2), the real (or complex) vectors x, u, and y are called state, inpuI, and...compulsory. Astro - loryi has been tried. No optimist would quarrel with the declaration of one of von NE!MAfrIiI’s direct successors that "exposure to the

  15. Adaptive Metropolis Sampling with Product Distributions

    NASA Technical Reports Server (NTRS)

    Wolpert, David H.; Lee, Chiu Fan

    2005-01-01

    The Metropolis-Hastings (MH) algorithm is a way to sample a provided target distribution pi(z). It works by repeatedly sampling a separate proposal distribution T(x,x') to generate a random walk {x(t)}. We consider a modification of the MH algorithm in which T is dynamically updated during the walk. The update at time t uses the {x(t' less than t)} to estimate the product distribution that has the least Kullback-Leibler distance to pi. That estimate is the information-theoretically optimal mean-field approximation to pi. We demonstrate through computer experiments that our algorithm produces samples that are superior to those of the conventional MH algorithm.

  16. Bonding brackets on white spot lesions pretreated by means of two methods.

    PubMed

    Vianna, Julia Sotero; Marquezan, Mariana; Lau, Thiago Chon Leon; Sant'Anna, Eduardo Franzotti

    2016-01-01

    The aim of this study was to evaluate the shear bond strength (SBS) of brackets bonded to demineralized enamel pretreated with low viscosity Icon Infiltrant resin (DMG) and glass ionomer cement (Clinpro XT Varnish, 3M Unitek) with and without aging. A total of 75 bovine enamel specimens were allocated into five groups (n = 15). Group 1 was the control group in which the enamel surface was not demineralized. In the other four groups, the surfaces were submitted to cariogenic challenge and white spot lesions were treated. Groups 2 and 3 were treated with Icon Infiltrant resin; Groups 4 and 5, with Clinpro XT Varnish. After treatment, Groups 3 and 5 were artificially aged. Brackets were bonded with Transbond XT adhesive system and SBS was evaluated by means of a universal testing machine. Statistical analysis was performed by one-way analysis of variance followed by Tukey post-hoc test. All groups tested presented shear bond strengths similar to or higher than the control group. Specimens of Group 4 had significantly higher shear bond strength values (p < 0.05) than the others. Pretreatment of white spot lesions, with or without aging, did not decrease the SBS of brackets.

  17. Evaluation of a new nano-filled restorative material for bonding orthodontic brackets.

    PubMed

    Bishara, Samir E; Ajlouni, Raed; Soliman, Manal M; Oonsombat, Charuphan; Laffoon, John F; Warren, John

    2007-01-01

    To compare the shear bond strength of a nano-hybrid restorative material, Grandio (Voco, Cuxhaven, Germany), to that of a traditional adhesive material (Transbond XT; 3M Unitek, Monrovia, CA, USA) when bonding orthodontic brackets. Forty teeth were randomly divided into 2 groups: 20 teeth were bonded with the Transbond adhesive system and the other 20 teeth with the Grandio restorative system, following manufacturer's instructions. Student t test was used to compare the shear bond strength of the 2 systems. Significance was predetermined at P 5 .05. The t test comparisons (t = 0.55) of the shear bond strength between the 2 adhesives indicated the absence of a significant (P = .585) difference. The mean shear bond strength for Grandio was 4.1 +/- 2.6 MPa and that for Transbond XT was 4.6 +/- 3.2 MPa. During debonding, 3 of 20 brackets (15%) bonded with Grandio failed without registering any force on the Zwick recording. None of the brackets bonded with Transbond XT had a similar failure mode. The newly introduced nano-filled composite materials can potentially be used to bond orthodontic brackets to teeth if its consistency can be more flowable to readily adhere to the bracket base.

  18. Electronic structures and population dynamics of excited states of xanthione and its derivatives

    NASA Astrophysics Data System (ADS)

    Fedunov, Roman G.; Rogozina, Marina V.; Khokhlova, Svetlana S.; Ivanov, Anatoly I.; Tikhomirov, Sergei A.; Bondarev, Stanislav L.; Raichenok, Tamara F.; Buganov, Oleg V.; Olkhovik, Vyacheslav K.; Vasilevskii, Dmitrii A.

    2017-09-01

    A new compound, 1,3-dimethoxy xanthione (DXT), has been synthesized and its absorption (stationary and transient) and luminescence spectra have been measured in n-hexane and compared with xanthione (XT) spectra. The pronounced broadening of xanthione vibronic absorption band related to the electronic transition to the second singlet excited state has been observed. Distinctions between the spectra of xanthione and its methoxy derivatives are discussed. Quantum chemical calculations of these compounds in the ground and excited electronic states have been accomplished to clarify the nature of electronic spectra changes due to modification of xanthione by methoxy groups. Appearance of a new absorption band of DXT caused by symmetry changes has been discussed. Calculations of the second excited state structure of xanthione and its methoxy derivatives confirm noticeable charge transfer (about 0.1 of the charge of an electron) from the methoxy group to thiocarbonyl group. Fitting of the transient spectra of XT and DXT has been fulfilled and the time constants of internal conversion S2 →S1 and intersystem crossing S1 →T1 have been determined. A considerable difference between the time constants of internal conversion S2 →S1 in XT and DXT is uncovered.

  19. The extent of aortic annulus calcification is a predictor of postprocedural eccentricity and paravalvular regurgitation: a pre- and postinterventional cardiac computed tomography angiography study.

    PubMed

    Bekeredjian, Raffi; Bodingbauer, Dorothea; Hofmann, Nina P; Greiner, Sebastian; Schuetz, Moritz; Geis, Nicolas A; Kauczor, Hans U; Bryant, Mark; Chorianopoulos, Emmanuel; Pleger, Sven T; Mereles, Derliz; Katus, Hugo A; Korosoglou, Grigorios

    2015-03-01

    To investigate if the extent of aortic valve calcification is associated with postprocedural prosthesis eccentricity and paravalvular regurgitation (PAR) in patients undergoing transcatheter aortic valve implantation (TAVI). Cardiac computed tomography angiography (CCTA) was performed before and 3 months after TAVI in 46 patients who received the self-expanding CoreValve and in 22 patients who underwent balloon-expandable Edwards Sapien XT implantation. Aortic annulus calcification was measured with CCTA prior to TAVI and prosthesis eccentricity was assessed with post-TAVI CCTA. Standard echocardiography was also performed in all patients at 3-month follow-up exam. Annulus eccentricity was reduced during TAVI using both implantation systems (from 0.23 ± 0.06 to 0.18 ± 0.07 using CoreValve and from 0.20 ± 0.07 to 0.05 ± 0.03 using Edwards Sapien XT; P<.001 for both). With Edwards Sapien XT, eccentricity reduction at the level of the aortic annulus was significantly higher compared with CoreValve (P<.001). Annulus eccentricity after CoreValve use was significantly related to absolute valve calcification and to valve calcification indexed to body surface area (BSA) (r = 0.48 and 0.50, respectively; P<.001 for both). Furthermore, a significant association was observed between aortic valve calcification and PAR (P<.01 by ANOVA) in patients who received CoreValve. Using ROC analysis, a cut-off value over 913 mm² aortic valve calcification predicted the occurrence of moderate or severe PAR with a sensitivity of 92% and a specificity of 63% (area under the curve = 0.75). Furthermore, multivariable analysis showed that aortic valve calcification was a robust predictor of postprocedural eccentricity and PAR, independent of the aortic annulus size and native valve eccentricity and of CoreValve prosthesis size (adjusted r = 0.46 and 0.50, respectively; P<.01 for both). Such associations were not present with the Edwards Sapien XT system. The extent of native aortic annulus calcification is predictive for postprocedural prosthesis eccentricity and PAR, which is an important marker for long-term mortality in patients undergoing TAVI. This observation applies for the CoreValve, but not for the Edwards Sapien XT valve.

  20. Deployment of an Advanced Electrocardiographic Analysis (A-ECG) to Detect Cardiovascular Risk in Career Firefighters

    NASA Technical Reports Server (NTRS)

    Dolezal, B. A.; Storer, T. W.; Abrazado, M.; Watne, R.; Schlegel, T. T.; Batalin, M.; Kaiser, W.; Smith, D. L.; Cooper, C. B.

    2011-01-01

    INTRODUCTION Sudden cardiac death is the leading cause of line of duty death among firefighters, accounting for approximately 45% of fatalities annually. Firefighters perform strenuous muscular work while wearing heavy, encapsulating personal protective equipment in high ambient temperatures, under chaotic and emotionally stressful conditions. These factors can precipitate sudden cardiac events like myocardial infarction, serious dysrhythmias, or cerebrovascular accidents in firefighters with underlying cardiovascular disease. Screening for cardiovascular risk factors is recommended but not always followed in this population. PHASER is a project charged with identifying and prioritizing risk factors in emergency responders. We have deployed an advanced ECG (A-ECG) system developed at NASA for improved sensitivity and specificity in the detection of cardiac risk. METHODS Forty-four professional firefighters were recruited to perform comprehensive baseline assessments including tests of aerobic performance and laboratory tests for fasting lipid profiles and glucose. Heart rate and conventional 12-lead ECG were obtained at rest and during incremental treadmill exercise testing (XT). In addition, a 5-min resting 12-lead A-ECG was obtained in a subset of firefighters (n=18) and transmitted over a secure networked system to a physician collaborator at NASA for advanced-ECG analysis. This A-ECG system has been proven, using myocardial perfusion and other imaging, to accurately identify a number of cardiac pathologies including coronary artery disease (CAD), left ventricular hypertrophy, hypertrophic cardiomyopathy, non-ischemic cardiomyopathy, and ischemic cardiomyopathy. RESULTS Subjects mean (SD) age was 43 (8) years, weight 91 (13) kg, and BMI of 28 (3) kg/square meter. Maximum oxygen uptake (VO2max) was 39 (9) ml/kg/min. This compares with the 45th %ile in healthy reference values and a recommended standard of 42 ml/kg/min for firefighters. The metabolic threshold (VO2Theta) above which lactate accumulates was 23 (8) ml/kg/min. The chronotropic index, a measure of cardiovascular strain during XT was 35 (8) /L compared with reference values for men of 40 /L. Total cholesterol, LDL-C and HDL-C were 202 (34),126 (29), and 55 (15) mg/dl, respectively. Fifty-one percent of subjects had .3 cardiovascular risk factors, 2 subjects had resting hypertension (BP.140/90), and 23 had pre-hypertension (.120/80 but <140/90). Seven had exaggerated exercise induced hypertension but only one had ST depression on XT ECG, at least one positive A-ECG score for CAD, and documented CAD based on cardiology referral. While all other subjects, including those with fewer risk factors, higher aerobic fitness, and normal exercise ECGs, were classified as healthy by A-ECG, there was no trend for association between risk factors and any of 20 A-ECG parameters in the grouped data. CONCLUSIONS A-ECG screening correctly identified the individual with CAD although there was no trend for A-ECG parameters to distinguish those with elevated BP or multiple risk factors but normal XT ECG. We have demonstrated that a new technology, advanced-ECG, can be introduced for remote firefighter risk assessment. This simple, time and cost-effective approach to risk identification that can be acquired remotely and transmitted securely can detect individuals potentially at risk for line-of-duty death. Additional research is needed to further document its value.

  1. Vibration measurement with nonlinear converter in the presence of noise

    NASA Astrophysics Data System (ADS)

    Mozuras, Almantas

    2017-10-01

    Conventional vibration measurement methods use the linear properties of physical converters. These methods are strongly influenced by nonlinear distortions, because ideal linear converters are not available. Practically, any converter can be considered as a linear one, when an output signal is very small. However, the influence of noise increases significantly and signal-to-noise ratio decreases at lower signals. When the output signal is increasing, the nonlinear distortions are also augmenting. If the wide spectrum vibration is measured, conventional methods face a harmonic distortion as well as intermodulation effects. Purpose of this research is to develop a measurement method of wide spectrum vibration by using a converter described by a nonlinear function of type f(x), where x =x(t) denotes the dependence of coordinate x on time t due to the vibration. Parameter x(t) describing the vibration is expressed as Fourier series. The spectral components of the converter output f(x(t)) are determined by using Fourier transform. The obtained system of nonlinear equations is solved using the least squares technique that permits to find x(t) in the presence of noise. This method allows one to carry out the absolute or relative vibration measurements. High resistance to noise is typical for the absolute vibration measurement, but it is necessary to know the Taylor expansion coefficients of the function f(x). If the Taylor expansion is not known, the relative measurement of vibration parameters is also possible, but with lower resistance to noise. This method allows one to eliminate the influence of nonlinear distortions to the measurement results, and consequently to eliminate harmonic distortion and intermodulation effects. The use of nonlinear properties of the converter for measurement gives some advantages related to an increased frequency range of the output signal (consequently increasing the number of equations) that allows one to decrease the noise influence on the measurement results. The greater is the nonlinearity the lower is noise. This method enables the use of the converters that are normally not suitable due to the high nonlinearity.

  2. OPAL: An Open-Source MPI-IO Library over Cray XT

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yu, Weikuan; Vetter, Jeffrey S; Canon, Richard Shane

    Parallel IO over Cray XT is supported by a vendor-supplied MPI-IO package. This package contains a proprietary ADIO implementation built on top of the sysio library. While it is reasonable to maintain a stable code base for application scientists' convenience, it is also very important to the system developers and researchers to analyze and assess the effectiveness of parallel IO software, and accordingly, tune and optimize the MPI-IO implementation. A proprietary parallel IO code base relinquishes such flexibilities. On the other hand, a generic UFS-based MPI-IO implementation is typically used on many Linux-based platforms. We have developed an open-source MPI-IOmore » package over Lustre, referred to as OPAL (OPportunistic and Adaptive MPI-IO Library over Lustre). OPAL provides a single source-code base for MPI-IO over Lustre on Cray XT and Linux platforms. Compared to Cray implementation, OPAL provides a number of good features, including arbitrary specification of striping patterns and Lustre-stripe aligned file domain partitioning. This paper presents the performance comparisons between OPAL and Cray's proprietary implementation. Our evaluation demonstrates that OPAL achieves the performance comparable to the Cray implementation. We also exemplify the benefits of an open source package in revealing the underpinning of the parallel IO performance.« less

  3. How Is the Enamel Affected by Different Orthodontic Bonding Agents and Polishing Techniques?

    PubMed

    Heravi, Farzin; Shafaee, Hooman; Abdollahi, Mojtaba; Rashed, Roozbeh

    2015-03-01

    The objective of this study was to assess the effect of new bonding techniques on enamel surface. Sixty upper central incisors were randomly divided into two equal groups. In the first group, metal brackets were bonded using TransbondXT and, in the second group, the same brackets were bonded with Maxcem Elite. The shear bond strength (SBS) of both agents to enamel was measured and the number and length of enamel cracks before bonding, after debonding and after polishing were compared. The number of visible cracks and the adhesive remnant index (ARI) scores in each group were also measured. There were significantly more enamel cracks in the Transbond XT group after debonding and polishing compared to the Maxcem Elite group. There was no significant difference in the length of enamel cracks between the two groups; but, in each group, a significant increase in the length of enamel cracks was noticeable after debonding. Polishing did not cause any statistically significant change in crack length. The SBS of Maxcem Elite was significantly lower than that of Transbond XT (95% confidence interval). Maxcem Elite offers clinically acceptable bond strength and can thus be used as a routine adhesive for orthodontic purposes since it is less likely to damage the enamel.

  4. Evaluation of dentin tubule occlusion after laser irradiation and desensitizing agent application.

    PubMed

    Kim, Min-Ho; Kim, Ryan Jin-Young; Lee, Woo-Cheol; Lee, In-Bog

    2015-10-01

    To evaluate the effects of lasers (Nd:YAG and Er:YAG) and of topical desensitizing agents on dentin tubule occlusion by measuring real-time dentin fluid flow (DFF). 32 molars were prepared with V-shape cavity at the cervical area, acid-etched, water rinsed, blotted dry, and treated with (1) Nd:YAG laser; (2) Er:YAG laser; (3) SuperSeal, a desensitizing agent; (4) ClinproXT, a resin-modified glass-ionomer (RMGI) varnish (n = 8 each). A real-time fluid flow measuring instrument (nano-Flow) was used to measure the DFF throughout the procedures. The DFF rates before and after the treatment were compared. Moreover, the surface topography of dentin tubules after each desensitizing method was examined using SEM. DFF varied among the groups. The DFF rate was significantly reduced after laser irradiation/application of the desensitizing agents (P < 0.05). ClinproXT showed the greatest reduction of DFF rate (71.9%), followed by the SuperSeal (34.8%) and laser groups (P< 0.05). However, there was no significant difference between the Nd:YAG (24.1%) and Er:YAG (20.6%) groups (P > 0.05). In SEM images, narrowed dentin tubules were observed in both lased groups and SuperSeal group. In the ClinproXT group, the occluded dentin tubules by the RMGI covering were observed.

  5. Kinetics and mechanism for platination of thione-containing nucleotides and oligonucleotides: evaluation of the salt dependence.

    PubMed

    Kjellström, Johan; Elmroth, Sofi K C

    2003-01-01

    Reactions of cis-[PtCl(NH(3))(CyNH(2))(OH(2))](+) (Cy=cyclohexyl) with thione-containing single-stranded oligonucleotides d(T(8)XT(8)) and d(XT(16)) (X=(s6)I or (s4)U) and the mononucleotides 4-thiouridine ((s4)UMP) and 6-mercaptoinosine ((s6)IMP) have been studied in aqueous solution at pH 4.1. The reaction kinetics was followed using HPLC methodology as a function of ionic strength in the interval 5.0 mM

  6. System Accuracy Evaluation of Four Systems for Self-Monitoring of Blood Glucose Following ISO 15197 Using a Glucose Oxidase and a Hexokinase-Based Comparison Method.

    PubMed

    Link, Manuela; Schmid, Christina; Pleus, Stefan; Baumstark, Annette; Rittmeyer, Delia; Haug, Cornelia; Freckmann, Guido

    2015-04-14

    The standard ISO (International Organization for Standardization) 15197 is widely accepted for the accuracy evaluation of systems for self-monitoring of blood glucose (SMBG). Accuracy evaluation was performed for 4 SMBG systems (Accu-Chek Aviva, ContourXT, GlucoCheck XL, GlucoMen LX PLUS) with 3 test strip lots each. To investigate a possible impact of the comparison method on system accuracy data, 2 different established methods were used. The evaluation was performed in a standardized manner following test procedures described in ISO 15197:2003 (section 7.3). System accuracy was assessed by applying ISO 15197:2003 and in addition ISO 15197:2013 criteria (section 6.3.3). For each system, comparison measurements were performed with a glucose oxidase (YSI 2300 STAT Plus glucose analyzer) and a hexokinase (cobas c111) method. All 4 systems fulfilled the accuracy requirements of ISO 15197:2003 with the tested lots. More stringent accuracy criteria of ISO 15197:2013 were fulfilled by 3 systems (Accu-Chek Aviva, ContourXT, GlucoMen LX PLUS) when compared to the manufacturer's comparison method and by 2 systems (Accu-Chek Aviva, ContourXT) when compared to the alternative comparison method. All systems showed lot-to-lot variability to a certain degree; 2 systems (Accu-Chek Aviva, ContourXT), however, showed only minimal differences in relative bias between the 3 evaluated lots. In this study, all 4 systems complied with the evaluated test strip lots with accuracy criteria of ISO 15197:2003. Applying ISO 15197:2013 accuracy limits, differences in the accuracy of the tested systems were observed, also demonstrating that the applied comparison method/system and the lot-to-lot variability can have a decisive influence on accuracy data obtained for a SMBG system. © 2015 Diabetes Technology Society.

  7. Information-based models for finance and insurance

    NASA Astrophysics Data System (ADS)

    Hoyle, Edward

    2010-10-01

    In financial markets, the information that traders have about an asset is reflected in its price. The arrival of new information then leads to price changes. The `information-based framework' of Brody, Hughston and Macrina (BHM) isolates the emergence of information, and examines its role as a driver of price dynamics. This approach has led to the development of new models that capture a broad range of price behaviour. This thesis extends the work of BHM by introducing a wider class of processes for the generation of the market filtration. In the BHM framework, each asset is associated with a collection of random cash flows. The asset price is the sum of the discounted expectations of the cash flows. Expectations are taken with respect (i) an appropriate measure, and (ii) the filtration generated by a set of so-called information processes that carry noisy or imperfect market information about the cash flows. To model the flow of information, we introduce a class of processes termed Lévy random bridges (LRBs), generalising the Brownian and gamma information processes of BHM. Conditioned on its terminal value, an LRB is identical in law to a Lévy bridge. We consider in detail the case where the asset generates a single cash flow X_T at a fixed date T. The flow of information about X_T is modelled by an LRB with random terminal value X_T. An explicit expression for the price process is found by working out the discounted conditional expectation of X_T with respect to the natural filtration of the LRB. New models are constructed using information processes related to the Poisson process, the Cauchy process, the stable-1/2 subordinator, the variance-gamma process, and the normal inverse-Gaussian process. These are applied to the valuation of credit-risky bonds, vanilla and exotic options, and non-life insurance liabilities.

  8. Investigation of Performance of Axial-Flow Compressor of XT-46 Turbine-Propeller Engine. I - Preliminary Investigation at 50-,70-, and 100-Percent Design Equivalent Speed

    NASA Technical Reports Server (NTRS)

    Creagh, John W.R.; Sandercrock, Donald M.

    1950-01-01

    An investigation is being conducted to determine the performance of the 12-stage axial-flow compressor of the XT-46 turbine-propeller engine. This compressor was designed to produce a pressure ratio of 9 at an adiabatic efficiency of 0.86. The design pressure ratios per stage were considerably greater than any employed in current aircraft gas-turbine engines using this type of compressor. The compressor performance was evaluated at two stations. The station near the entrance section of the combustors indicated a peak pressure ratio of 6.3 at an adiabatic efficiency of 0.63 for a corrected weight flow of 23.1 pounds per second. The other, located one blade-chord downstream of the last stator row, indicated a peak pressure ratio of 6.97 at an adiabatic efficiency of 0.81 for a corrected weight flow of 30.4 pounds per second. The difference in performance obtained at the two stations is attributed to shock waves in the vicinity of the last stator row. These shock waves and the accompanying flow choking, together with interstage circulatory flows, shift the compressor operating curves into the region where surge would normally occur. The inability of the compressor to meet design pressure ratio is probably due to boundary-layer buildup in the last stages, which cause axial velocities greater than design values that, in turn, adversely affect the angles of attack and turning angles in these blade rows.

  9. Nonequilibrium Probabilistic Dynamics of the Logistic Map at the Edge of Chaos

    NASA Astrophysics Data System (ADS)

    Borges, Ernesto P.; Tsallis, Constantino; Añaños, Garín F.; de Oliveira, Paulo Murilo

    2002-12-01

    We consider nonequilibrium probabilistic dynamics in logisticlike maps xt+1=1-a|xt|z, (z>1) at their chaos threshold: We first introduce many initial conditions within one among W>>1 intervals partitioning the phase space and focus on the unique value qsen<1 for which the entropic form Sq≡(1- ∑i=1Wpqi)/(q-1) linearly increases with time. We then verify that Sqsen(t)-Sqsen(∞) vanishes like t-1/[qrel(W)-1] [qrel(W)>1]. We finally exhibit a new finite-size scaling, qrel(∞)-qrel(W)~W- |qsen|. This establishes quantitatively, for the first time, a long pursued relation between sensitivity to the initial conditions and relaxation, concepts which play central roles in nonextensive statistical mechanics.

  10. Adhoc Wireless Network Control: Energy Efficiency and Hidden Terminal Considerations

    DTIC Science & Technology

    2009-12-01

    Pnl (t) +Bn(t), Emax ) , (57) Ynl(t+ 1) = [Ynl(t)−Rnl,in(t)] + + γnl(t), (58) Dn(t+ 1) = [Dn(t...1− δ)Bn(t)] + + ∑ l∈On Pnl (t), (59) subject to constraints Rnl,in(t) ≤ Vnl(t) +Anl(t) ∀n, l, t, P (t) ∈ PS(t), ∑ l∈On Pnl (t) ≤ min ( En(t), P̂ ) ∀n...γnl(t)] ∣ ∣ ∣ ∣ ∣ ∣ X(t)   − 2E   ∑ n,l [Unl(t)µnl (S(t),P (t))−Dn(t) Pnl (t)] ∣ ∣ ∣ ∣ ∣ ∣ X(t)  − 2E   ∑ n,l [ηYnl(t)−

  11. A comparative study of shear bond strength of orthodontic bracket after acid-etched and Er:YAG treatment on enamel surface

    NASA Astrophysics Data System (ADS)

    Leão, Juliana C.; Mota, Cláudia C. B. O.; Cassimiro-silva, Patricia F.; Gomes, Anderson S. L.

    2016-02-01

    This study aimed to evaluate the shear bond strength (SBS) of teeth prepared for orthodontic bracket bonding with 37% phosphoric acid and Er:YAG laser. Forty bovine incisors were divided into two groups. In Group I, the teeth were conditioned with 37% phosphoric acid and brackets were bonded with Transbond XT; in Group II, the teeth were irradiated with Er:YAG and bonding with Transbond XT. After SBS test, the adhesive remnant index was determined. Adhesion to dental hard tissues after Er:YAG laser etching was inferior to that obtained after acid etching but exceeded what is believed to be clinically sufficient strength, and therefore can be used in patients.

  12. Integrating Grid Services into the Cray XT4 Environment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NERSC; Cholia, Shreyas; Lin, Hwa-Chun Wendy

    2009-05-01

    The 38640 core Cray XT4"Franklin" system at the National Energy Research Scientific Computing Center (NERSC) is a massively parallel resource available to Department of Energy researchers that also provides on-demand grid computing to the Open Science Grid. The integration of grid services on Franklin presented various challenges, including fundamental differences between the interactive and compute nodes, a stripped down compute-node operating system without dynamic library support, a shared-root environment and idiosyncratic application launching. Inour work, we describe how we resolved these challenges on a running, general-purpose production system to provide on-demand compute, storage, accounting and monitoring services through generic gridmore » interfaces that mask the underlying system-specific details for the end user.« less

  13. neXtProt: organizing protein knowledge in the context of human proteome projects.

    PubMed

    Gaudet, Pascale; Argoud-Puy, Ghislaine; Cusin, Isabelle; Duek, Paula; Evalet, Olivier; Gateau, Alain; Gleizes, Anne; Pereira, Mario; Zahn-Zabal, Monique; Zwahlen, Catherine; Bairoch, Amos; Lane, Lydie

    2013-01-04

    About 5000 (25%) of the ~20400 human protein-coding genes currently lack any experimental evidence at the protein level. For many others, there is only little information relative to their abundance, distribution, subcellular localization, interactions, or cellular functions. The aim of the HUPO Human Proteome Project (HPP, www.thehpp.org ) is to collect this information for every human protein. HPP is based on three major pillars: mass spectrometry (MS), antibody/affinity capture reagents (Ab), and bioinformatics-driven knowledge base (KB). To meet this objective, the Chromosome-Centric Human Proteome Project (C-HPP) proposes to build this catalog chromosome-by-chromosome ( www.c-hpp.org ) by focusing primarily on proteins that currently lack MS evidence or Ab detection. These are termed "missing proteins" by the HPP consortium. The lack of observation of a protein can be due to various factors including incorrect and incomplete gene annotation, low or restricted expression, or instability. neXtProt ( www.nextprot.org ) is a new web-based knowledge platform specific for human proteins that aims to complement UniProtKB/Swiss-Prot ( www.uniprot.org ) with detailed information obtained from carefully selected high-throughput experiments on genomic variation, post-translational modifications, as well as protein expression in tissues and cells. This article describes how neXtProt contributes to prioritize C-HPP efforts and integrates C-HPP results with other research efforts to create a complete human proteome catalog.

  14. Performance evaluation of the Abbott CELL-DYN Emerald for use as a bench-top analyzer in a research setting.

    PubMed

    Khoo, T-L; Xiros, N; Guan, F; Orellana, D; Holst, J; Joshua, D E; Rasko, J E J

    2013-08-01

    The CELL-DYN Emerald is a compact bench-top hematology analyzer that can be used for a three-part white cell differential analysis. To determine its utility for analysis of human and mouse samples, we evaluated this machine against the larger CELL-DYN Sapphire and Sysmex XT2000iV hematology analyzers. 120 human (normal and abnormal) and 30 mouse (normal and abnormal) samples were analyzed on both the CELL-DYN Emerald and CELL-DYN Sapphire or Sysmex XT2000iV analyzers. For mouse samples, the CELL-DYN Emerald analyzer required manual recalibration based on the histogram populations. Analysis of the CELL-DYN Emerald showed excellent precision, within accepted ranges (white cell count CV% = 2.09%; hemoglobin CV% = 1.68%; platelets CV% = 4.13%). Linearity was excellent (R² ≥ 0.99), carryover was minimal (<1%), and overall interinstrument agreement was acceptable for both human and mouse samples. Comparison between the CELL-DYN Emerald and Sapphire analyzers for human samples or Sysmex XT2000iV analyzer for mouse samples showed excellent correlation for all parameters. The CELL-DYN Emerald was generally comparable to the larger reference analyzer for both human and mouse samples. It would be suitable for use in satellite research laboratories or as a backup system in larger laboratories. © 2012 John Wiley & Sons Ltd.

  15. Influence of Adhesives and Methods of Enamel Pretreatment on the Shear Bond Strength of Orthodontic Brackets.

    PubMed

    Jurišić, Sanja; Jurišić, Gordan; Jurić, Hrvoje

    2015-12-01

    The objective of present study was to examine influence of adhesives and methods of enamel pretreatment on the shear bond strength (SBS) of orthodontic brackets. The adhesives used were resin-reinforced glass ionomer cements-GIC (Fuji Ortho LC) and composite resin (Transbond XT). The experimental sample consisted of 80 extracted human first premolars. The sample was divided into four equal groups, and the metal brackets were bonded with different enamel pretreatments by using two adhesives: group A-10% polyacrylic acid; Fuji Ortho LC, group B-37% phosphoric acid; Fuji Ortho LC, group C-self etching primer; Transbond XT, group D-37% phosphoric acid, primer; Transbond XT. SBS of brackets was measured. After debonding of brackets, the adhesive remnant index (ARI) was evaluated. After the statistical analysis of the collected data was performed (ANOVA; Sheffe post-hoc test), the results showed that significantly lower SBS of the group B was found in relation to the groups C (p=0.031) and D (p=0.026). The results of ARI were similar in all testing groups and it was not possible to determine any statistically significant difference of the ARI (Chi- square test) between all four experimental groups. The conclusion is that the use of composite resins material with appropriate enamel pretreatment according to manufacturer's recommendation is the "gold standard" for brackets bonding for fixed orthodontic appliances.

  16. Structure-Specificity Relationships of an Intracellular Xylanase from Geobacillus stearothermophilus

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Solomon,V.; Teplitsky, A.; Shulami, S.

    2007-01-01

    Geobacillus stearothermophilus T-6 is a thermophilic Gram-positive bacterium that produces two selective family 10 xylanases which both take part in the complete degradation and utilization of the xylan polymer. The two xylanases exhibit significantly different substrate specificities. While the extracellular xylanase (XT6; MW 43.8 kDa) hydrolyzes the long and branched native xylan polymer, the intracellular xylanase (IXT6; MW 38.6 kDa) preferentially hydrolyzes only short xylo-oligosaccharides. In this study, the detailed three-dimensional structure of IXT6 is reported, as determined by X-ray crystallography. It was initially solved by molecular replacement and then refined at 1.45 {angstrom} resolution to a final R factormore » of 15.0% and an R{sub free} of 19.0%. As expected, the structure forms the classical ({alpha}/{beta}){sub 8} fold, in which the two catalytic residues (Glu134 and Glu241) are located on the inner surface of the central cavity. The structure of IXT6 was compared with the highly homologous extracellular xylanase XT6, revealing a number of structural differences between the active sites of the two enzymes. In particular, structural differences derived from the unique subdomain in the carboxy-terminal region of XT6, which is completely absent in IXT6. These structural modifications may account for the significant differences in the substrate specificities of these otherwise very similar enzymes.« less

  17. Strain-specific reverse transcriptase PCR assay: means to distinguish candidate vaccine from wild-type strains of respiratory syncytial virus.

    PubMed Central

    Zheng, H; Peret, T C; Randolph, V B; Crowley, J C; Anderson, L J

    1996-01-01

    Candidate live-virus vaccines for respiratory syncytial virus are being developed and are beginning to be evaluated in clinical trials. To distinguish candidate vaccine strains from wild-type strains isolated during these trials, we developed PCR assays specific to two sets of candidate vaccine strains. The two sets were a group A strain (3A), its three attenuated, temperature-sensitive variant strains, a group B strain (2B), and its four attenuated, temperature-sensitive variant strains. The PCR assays were evaluated by testing 18 group A wild-type strains, the 3A strains, 9 group B wild-type strains, and the 2B strains. PCR specific to group A wild-type strains amplified only group A wild-type strains, and 3A-specific PCR amplified only 3A strains. PCR specific to group B wild-type strains amplified all group A and group B strains but gave a 688-bp product for group B wild-type strains, a 279-bp product for 2B strains, a 547-bp product for all group A strains, and an additional 688-bp product for some group A strains, including 3A strains. These types of PCR assays can, in conjunction with other methods, be used to efficiently distinguish candidate vaccine strains from other respiratory syncytial virus strains. PMID:8789010

  18. Transapical tricuspid valve-in-ring implantation: An alternative approach to a challenging clinical scenario.

    PubMed

    Girdauskas, Evaldas; Lauer, Bernward; Kuntze, Thomas

    2018-04-01

    We report on a transapical tricuspid valve-in-ring implantation performed via right ventricular apex using the Sapien-XT-prosthesis. A 57-year-old woman with recurrent episodes of right heart failure and three previous sternotomies, including tricuspid valve repair with a 32 mm Carpentier-Edwards-Classic annuloplasty ring was admitted due to recurrent severe tricuspid regurgitation. Given the excessive surgical risk, a 29 mm Sapien-XT-prosthesis was selected for valve-in-ring implantation. Transapical valve-in-ring implantation procedure was uneventful. Predischarge echocardiography showed only trace paravalvular tricuspid regurgitation in the septal region. Transapical approach via right ventricular apex is a viable alternative for tricuspid valve-in-ring implantation in selected high-risk patients. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  19. Theoretical information measurement in nonrelativistic time-dependent approach

    NASA Astrophysics Data System (ADS)

    Najafizade, S. A.; Hassanabadi, H.; Zarrinkamar, S.

    2018-02-01

    The information-theoretic measures of time-dependent Schrödinger equation are investigated via the Shannon information entropy, variance and local Fisher quantities. In our calculations, we consider the two first states n = 0,1 and obtain the position Sx (t) and momentum Sp (t) Shannon entropies as well as Fisher information Ix (t) in position and momentum Ip (t) spaces. Using the Fourier transformed wave function, we obtain the results in momentum space. Some interesting features of the information entropy densities ρs (x,t) and γs (p,t), as well as the probability densities ρ (x,t) and γ (p,t) for time-dependent states are demonstrated. We establish a general relation between variance and Fisher's information. The Bialynicki-Birula-Mycielski inequality is tested and verified for the states n = 0,1.

  20. Vehicle Technologies Program Educational Activities

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    2011-12-13

    Description of educational activities including: EcoCAR2: Plugging In to the Future, EcoCAR: The NeXt Challenge, Green Racing, Automotive X Prize, Graduate Technology Automotive Education (GATE), and Hydrogen Education.

  1. Identification, Classification, and Phylogeny of the Pathogenic Species Exophiala jeanselmei and Related Species by Mitochondrial Cytochrome b Gene Analysis

    PubMed Central

    Wang, Li; Yokoyama, Koji; Miyaji, Makoto; Nishimura, Kazuko

    2001-01-01

    We analyzed a 402-bp sequence of the mitochondrial cytochrome b gene of 34 strains of Exophiala jeanselmei and 16 strains representing 12 related species. The strains of E. jeanselmei were classified into 20 DNA types and 17 amino acid types. The differences between these strains were found in 1 to 60 nucleotides and 1 to 17 amino acids. On the basis of the identities and similarities of nucleotide and amino acid sequences, some strains were reidentified: i.e., two strains of E. jeanselmei var. hetermorpha and one strain of E. castellanii as E. dermatitidis (including the type strain), three strains of E. jeanselmei as E. jeanselmei var. lecanii-corni (including the type strain), three strains of E. jeanselmei as E. bergeri (including the type strain), seven strains of E. jeanselmei as E. pisciphila (including the type strain), seven strains of E. jeanselmei as E. jeanselmei var. jeanselmei (including the type strain), one strain of E. jeanselmei as Fonsecaea pedrosoi (including the type strain), and one strain of E. jeanselmei as E. spinifera (including the type strain). Some E. jeanselmei strains showed distinct nucleotide and amino acid sequences. The amino-acid-based UPGMA (unweighted pair group method with the arithmetic mean) tree exhibited nearly the same topology as those of the DNA-based trees obtained by neighbor joining, maximum parsimony, and maximum likelihood methods. PMID:11724862

  2. Effect of bleaching on microhardness of esthetic restorative materials.

    PubMed

    Malkondu, Özlem; Yurdagüven, Haktan; Say, Esra Can; Kazazoğlu, Ender; Soyman, Mübin

    2011-01-01

    This study evaluated the effect of a high-concentration carbamide peroxide–containing home bleaching system (Opalescence PF) and a hydrogen peroxide–containing over-the-counter bleaching system (Treswhite Supreme) on the microhardness of two nanocomposites (Filtek Supreme XT and Premise) and leucite-reinforced glass ceramic (Empress Esthetic), glass ceramic (Empress 2 layering), and feldspathic porcelain (Matchmaker MC). A total of 100 specimens, 20 of each kind of the restorative materials, 2 mm in thickness and 10 mm in diameter, were fabricated. Then the specimens were polished with SiC paper and 1 μm alumina polishing paste. After polishing, porcelain specimens were glazed in accordance with the manufacturer's instructions. Each type of restorative material was then randomly divided into two groups (n=10), and the specimens were treated with either Opalescence PF or Treswhite Supreme. The microhardness of the specimens before bleaching (baseline) and after bleaching was determined using a digital microhardness tester. Data were analyzed using the Mann-Whitney U-test and the Wilcoxon test. Opalescence PF significantly influenced the hardness of all the restorative materials. Statistically significant decreases with respect to before bleaching were found for Premise (p=0.005), Empress Esthetic (p=0.003), Empress 2 layering (p=0.005), and Matchmaker-MC (p=0.003), whereas a statistically significant increase was observed in Filtek Supreme XT (p=0.028). The difference in the microhardness values between before and after bleaching using Treswhite Supreme was statistically significant only for Premise (p=0.022). High-concentration carbamide peroxide–containing home bleaching may affect the microhardness of restorative materials.

  3. System and method for constructing filters for detecting signals whose frequency content varies with time

    DOEpatents

    Qian, Shie; Dunham, Mark E.

    1996-01-01

    A system and method for constructing a bank of filters which detect the presence of signals whose frequency content varies with time. The present invention includes a novel system and method for developing one or more time templates designed to match the received signals of interest and the bank of matched filters use the one or more time templates to detect the received signals. Each matched filter compares the received signal x(t) with a respective, unique time template that has been designed to approximate a form of the signals of interest. The robust time domain template is assumed to be of the order of w(t)=A(t)cos{2.pi..phi.(t)} and the present invention uses the trajectory of a joint time-frequency representation of x(t) as an approximation of the instantaneous frequency function {.phi.'(t). First, numerous data samples of the received signal x(t) are collected. A joint time frequency representation is then applied to represent the signal, preferably using the time frequency distribution series (also known as the Gabor spectrogram). The joint time-frequency transformation represents the analyzed signal energy at time t and frequency .function., P(t,f), which is a three-dimensional plot of time vs. frequency vs. signal energy. Then P(t,f) is reduced to a multivalued function f(t), a two dimensional plot of time vs. frequency, using a thresholding process. Curve fitting steps are then performed on the time/frequency plot, preferably using Levenberg-Marquardt curve fitting techniques, to derive a general instantaneous frequency function .phi.'(t) which best fits the multivalued function f(t), a trajectory of the joint time-frequency domain representation of x(t). Integrating .phi.'(t) along t yields .phi.(t), which is then inserted into the form of the time template equation. A suitable amplitude A(t) is also preferably determined. Once the time template has been determined, one or more filters are developed which each use a version or form of the time template.

  4. Does Undersizing of Transcatheter Aortic Valve Bioprostheses during Valve-in-Valve Implantation Avoid Coronary Obstruction? An In Vitro Study.

    PubMed

    Stock, Sina; Scharfschwerdt, Michael; Meyer-Saraei, Roza; Richardt, Doreen; Charitos, Efstratios I; Sievers, Hans-Hinrich; Hanke, Thorsten

    2017-04-01

    Background  The transcatheter aortic valve-in-valve implantation (TAViVI) is an evolving treatment strategy for degenerated surgical aortic valve bioprostheses (SAVBs) in patients with high operative risk. Although hemodynamics is excellent, there is some concern regarding coronary obstruction, especially in SAVB with externally mounted leaflet tissue, such as the Trifecta (St. Jude Medical Inc., St. Paul, Minnesota, United States). We investigated coronary flow and hydrodynamics before and after TAViVI in a SAVB with externally mounted leaflet tissue (St. Jude Medical, Trifecta) with an undersized transcatheter aortic valve bioprosthesis (Edwards Sapien XT; Edwards Lifesciences LLC, Irvine, California, United States) in an in vitro study. Materials and Methods  An aortic root model was constructed incorporating geometric dimensions known as risk factors for coronary obstruction. Investigating the validity of this model, we primarily performed recommended TAViVI with the Sapien XT (size 26 mm) in a Trifecta (size 25 mm) in a mock circulation. Thereafter, hydrodynamic performance and coronary flow (left/right coronary diastolic flow [lCF/rCF]) after TAViVI with an undersized Sapien XT (size 23 mm) in a Trifecta (size 25 mm) were investigated at two different coronary ostia heights (COHs, 8 and 10 mm). Results  Validation of the model led to significant coronary obstruction ( p  < 0.001). Undersized TAViVI showed no significant reduction with respect to coronary flow (lCF: COH 8 mm, 0.90-0.87 mL/stroke; COH 10 mm, 0.89-0.82 mL/stroke and rCF: COH 8 mm, 0.64-0.60 mL/stroke; COH 10 mm, 0.62-0.58 mL/stroke). Mean transvalvular gradients (4-5 mm Hg, p  < 0.001) increased significantly after TAViVI. Conclusions  In our in vitro model, undersized TAViVI with the balloon-expandable Sapien XT into a modern generation SAVB (Trifecta) successfully avoided coronary flow obstruction. Georg Thieme Verlag KG Stuttgart · New York.

  5. Effects of Different Combinations of Er:YAG Laser-Adhesives on Enamel Demineralization and Bracket Bond Strength

    PubMed Central

    Nalçacı, Ruhi; Üşümez, Serdar; Malkoç, Sıddık

    2016-01-01

    Abstract Objective: The purpose of this study was to investigate the demineralization around brackets and shear bond strength (SBS) of brackets bonded to Er:YAG laser-irradiated enamel at different power settings with various adhesive systems combinations. Methods: A total of 108 premolar teeth were used in this study. Teeth were assigned into three groups according to the etching procedure, then each group divided into three subgroups based on the application of different adhesive systems. There were a total of nine groups as follows. Group 1: Acid + Transbond XT Primer; group 2: Er:YAG (100 mJ, 10 Hz) etching + Transbond XT Primer; group 3: Er:YAG (200 mJ, 10 Hz) etching + Transbond XT Primer; group 4: Transbond Plus self-etching primer (SEP); group 5: Er:YAG (100 mJ, 10 Hz) etching + Transbond Plus SEP; group 6: Er:YAG (200 mJ, 10 Hz) etching + Transbond Plus SEP; group 7: Clearfil Protect Bond; group 8: Er:YAG (100 mJ, 10 Hz) etching + Clearfil Protect Bond; group 9: Er:YAG (200 mJ, 10 Hz) etching + Clearfil Protect Bond. Brackets were bonded with Transbond XT Adhesive Paste in all groups. Teeth to be evaluated for demineralization and SBS were exposed to pH and thermal cyclings, respectively. Then, demineralization samples were scanned with micro-CT to determine lesion depth values. For SBS test, a universal testing machine was used and adhesive remnant was index scored after debonding. Data were analyzed statistically. Results: No significant differences were found among the lesion depth values of the various groups, except for G7 and G8, in which the lowest values were recorded. The lowest SBS values were in G7, whereas the highest were in G9. The differences between the other groups were not significant. Conclusions: Er:YAG laser did not have a positive effect on prevention of enamel demineralization. When two step self-etch adhesive is preferred for bonding brackets, laser etching at 1 W (100 mJ, 10 Hz) is suggested to improve SBS of brackets. PMID:26987047

  6. Effects of Different Combinations of Er:YAG Laser-Adhesives on Enamel Demineralization and Bracket Bond Strength.

    PubMed

    Çokakoğlu, Serpil; Nalçacı, Ruhi; Üşümez, Serdar; Malkoç, Sıddık

    2016-04-01

    The purpose of this study was to investigate the demineralization around brackets and shear bond strength (SBS) of brackets bonded to Er:YAG laser-irradiated enamel at different power settings with various adhesive systems combinations. A total of 108 premolar teeth were used in this study. Teeth were assigned into three groups according to the etching procedure, then each group divided into three subgroups based on the application of different adhesive systems. There were a total of nine groups as follows. Group 1: Acid + Transbond XT Primer; group 2: Er:YAG (100 mJ, 10 Hz) etching + Transbond XT Primer; group 3: Er:YAG (200 mJ, 10 Hz) etching + Transbond XT Primer; group 4: Transbond Plus self-etching primer (SEP); group 5: Er:YAG (100 mJ, 10 Hz) etching + Transbond Plus SEP; group 6: Er:YAG (200 mJ, 10 Hz) etching + Transbond Plus SEP; group 7: Clearfil Protect Bond; group 8: Er:YAG (100 mJ, 10 Hz) etching + Clearfil Protect Bond; group 9: Er:YAG (200 mJ, 10 Hz) etching + Clearfil Protect Bond. Brackets were bonded with Transbond XT Adhesive Paste in all groups. Teeth to be evaluated for demineralization and SBS were exposed to pH and thermal cyclings, respectively. Then, demineralization samples were scanned with micro-CT to determine lesion depth values. For SBS test, a universal testing machine was used and adhesive remnant was index scored after debonding. Data were analyzed statistically. No significant differences were found among the lesion depth values of the various groups, except for G7 and G8, in which the lowest values were recorded. The lowest SBS values were in G7, whereas the highest were in G9. The differences between the other groups were not significant. Er:YAG laser did not have a positive effect on prevention of enamel demineralization. When two step self-etch adhesive is preferred for bonding brackets, laser etching at 1 W (100 mJ, 10 Hz) is suggested to improve SBS of brackets.

  7. Effect of Instrument Lubricants on the Surface Degree of Conversion and Crosslinking Density of Nanocomposites.

    PubMed

    de Paula, Felipe Costa; Valentin, Regis de Souza; Borges, Boniek Castillo Dutra; Medeiros, Maria Cristina Dos Santos; de Oliveira, Raiza Freitas; da Silva, Ademir Oliveira

    2016-01-01

    The surface degree of conversion and crosslink density of composites should not be affected by the use of instrument lubricants in order to provide long-lasting tooth restorations. This study aimed to analyze the effect of instrument lubricants on the degree of conversion and crosslink density of nanocomposites. Samples (N = 10) were fabricated according to the composites (Filtek Z350 XT, 3M ESPE, St. Paul, MN, USA; and IPS Empress Direct, Ivoclar Vivadent AG, Schaan, Liechtenstein and lubricants used (Adper Single Bond 2 and Scotchbond Multi-Purpose bonding agent adhesive systems, 3M ESPE; 70% ethanol, absolute ethanol, and no lubricant). Single composite increments were inserted into a Teflon mold using the same dental instrument. The composite surface was then modeled using a brush wiped with each adhesive system and a spatula wiped with each ethanol. The control group was fabricated with no additional modeling. The surface degree of conversion and crosslink density were measured by Fourier transform infrared spectroscopy and the hardness decrease test, respectively. Data were analyzed using two-way analysis of variance and the Tukey's test (p < 0.05). Filtek Z350 XT showed statistically similar degree of conversion regardless of the lubricant used, whereas the use of adhesive systems and 70% ethanol decreased the degree of conversion for IPS Empress Direct. Only Scotchbond Multi-Purpose bonding agent decreased crosslink density for Filtek Z350 XT, whereas both adhesive systems decreased crosslink density for IPS Empress Direct. Filtek Z350 XT appeared to be less sensitive to the effects of lubricants, and absolute ethanol did not affect the degree of conversion and crosslink density of the nanocomposites tested. Although the use of lubricants may be recommended to minimize the stickiness of dental instruments and composite resin, dentists should choose materials that do not have a negative effect on the surface properties of composites. Only the use of absolute ethanol safely maintains the surface integrity of nanocomposites in comparison with adhesive system and 70% ethanol. © 2015 Wiley Periodicals, Inc.

  8. Stability of Nonstationary Cooling of Pure Hydrogen Gas with Respect to the Number of Discrete Levels Taken into Account

    NASA Astrophysics Data System (ADS)

    Belova, O. M.; Bychkov, K. V.

    2018-03-01

    The effect of the number K of atomic hydrogen levels taken into account on the cooling of the gas behind a shock front is studied. The calculations are done for the conditions in the atmospheres of long-period Mira Ceti type variables. K ranges from 2 to 25. The electron temperature Te(t; K) and ionization state x(r,K) asymptotically approach limiting functions Te(t) and x(t) that are independent of K. After the maximum electron temperature is reached, a partial equilibrium phase sets in, during which the populations of the highly excited discrete levels with principal quantum numbers ≥ 8 obey the Saha equation for the instantaneous electron temperature and density.

  9. Phage Types and Genotypes of Shiga Toxin-Producing Escherichia coli O157:H7 Isolates from Humans and Animals in Spain: Identification and Characterization of Two Predominating Phage Types (PT2 and PT8)

    PubMed Central

    Mora, Azucena; Blanco, Miguel; Blanco, Jesús E.; Alonso, M. Pilar; Dhabi, Ghizlane; Thomson-Carter, Fiona; Usera, Miguel A.; Bartolomé, Rosa; Prats, Guillermo; Blanco, Jorge

    2004-01-01

    Phage typing and DNA macrorestriction fragment analysis by pulsed-field electrophoresis (PFGE) were used for the epidemiological subtyping of a collection of Shiga toxin-producing Escherichia coli (STEC) O157:H7 strains isolated in Spain between 1980 and 1999. Phage typing distinguished a total of 18 phage types among 171 strains isolated from different sources (67 humans, 82 bovines, 12 ovines, and 10 beef products). However, five phage types, phage type 2 (PT2; 42 strains), PT8 (33 strains), PT14 (14 strains), PT21/28 (11 strains), and PT54 (16 strains), accounted for 68% of the study isolates. PT2 and PT8 were the most frequently found among strains from both humans (51%) and bovines (46%). Interestingly, we detected a significant association between PT2 and PT14 and the presence of acute pathologies. A group of 108 of the 171 strains were analyzed by PFGE, and 53 distinct XbaI macrorestriction patterns were identified, with 38 strains exhibiting unique PFGE patterns. In contrast, phage typing identified 15 different phage types. A total of 66 phage type-PFGE subtype combinations were identified among the 108 strains. PFGE subtyping differentiated between unrelated strains that exhibited the same phage type. The most common phage type-PFGE pattern combinations were PT2-PFGE type 1 (1 human and 11 bovine strains), PT8-PFGE type 8 (2 human, 6 bovine, and 1 beef product strains), PT2-PFGE subtype 4A (1 human, 3 bovine, and 1 beef product strains). Nine (29%) of 31 human strains showed phage type-PFGE pattern combinations that were detected among the bovine strains included in this study, and 26 (38%) of 68 bovine strains produced phage type-PFGE pattern combinations observed among human strains included in this study, confirming that cattle are a major reservoir of strains pathogenic for humans. PT2 and PT8 strains formed two groups which differed from each other in their motilities, stx genotypes, PFGE patterns, and the severity of the illnesses that they caused. PMID:15364983

  10. Comparative studies on the internal defense system of schistosome-resistant and -susceptible amphibious snail Oncomelania nosophora 1. Comparative morphological and functional studies on hemocytes from both snails.

    PubMed

    Sasaki, Yuri; Furuta, Emiko; Kirinoki, Masashi; Seo, Naomi; Matsuda, Hajime

    2003-10-01

    Two morphologically distinct blood cell types (hemocytes), Type I and Type II were found coexisting in hemolymph from two kinds of snails, Oncomelania nosophora strain, viz. from the Nirasaki strain (schistosome-resistant snail) and the Kisarazu strain (schistosome-susceptible snail). Ten min after inoculation of SRBC, the majority of Type I cells from Nirasaki strain flattened and spread over the surface of the glass plate by extending pseudopodia. In the Kisarazu strain, Type I cells adhered to the surface of substrate with spike-like filopodia, but did not form spreading lamellipodia. Type I cell from the Nirasaki strain phagocytosed SRBC but that from the Kisarazu strain did not. The starting time of recognition of foreign materials was slightly different in the Type I hemocytes from the two strains. Type II cells from both strains were round and lymphocyte-like. Ten or sixty min after incubation, Type II cells from neither strain adhered to the surface of substrate or SRBC, and did not phagocytose SRBC. Type II cells from the Nirasaki strain were quite similar to those from the Kisarazu strain. We concluded that Type I cells from the schistosome-resistant snail, Nirasaki strain, possessed higher phagocytic activity than those from the susceptible snail, Kisarazu strain, despite the morphological similarities of the hemocytes from both strains.

  11. Definition of propulsion system for V/STOL research and technology aircraft

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Wind tunnel test support, aircraft contractor support, a propulsion system computer card deck, preliminary design studies, and propulsion system development plan are reported. The Propulsion system consists of two lift/cruise turbofan engines, one turboshaft engine and one lift fan connected together with shafting into a combiner gearbox. Distortion parameter levels from 40 x 80 test data were within the established XT701-AD-700 limits. The three engine-three fan system card deck calculates either vertical or conventional flight performance, installed or uninstalled. Design study results for XT701 engine modifications, bevel gear cross shaft location, fixed and tilt fan frames and propulsion system controls are described. Optional water-alcohol injection increased total net thrust 10.3% on a 90 F day. Engines have sufficient turbine life for 500 hours of the RTA duty cycle.

  12. Dynamic Stability of Structures: Application to Frames, Cylindrical Shells and Other Systems.

    DTIC Science & Technology

    1982-02-01

    L0G XNX= XNXX 102. XNI:XNXX 102 GO TU 7-* 103 72 wRIkL(6,52)YFr4Xv XPKE.SONXvACCUR 104. XNXZXPRE. LOS XN11=XFRES 106 GO To 74. 107 73 WRITLC,5.3)Xt4X...YFviq~~ T19MAXvI,£LPRIN4TwwXNPvLP) 146 IF (iNxxF.xE.4)xPt~s=xWI IF (1NXXPX.tJE.4.) XNXX =XtAP 444 IDcz.T=IOT 147 IF (IsSF.tjE. )GO TO Z14 DC 213 :i1...T.IN& i-3T3(POT,PCrMq Sr TR TA qi~ IP Sv. ISA, XNXX 1263 C POT - F)TEN1TLAL EOi)RGY 1264. C STRY - U;JI TEND SHORTENIN.G FOR~ Yz0 * 1265 C STRA - .V-k-Gc

  13. Influence of Adhesives and Methods of Enamel Pretreatment on the Shear Bond Strength of Orthodontic Brackets

    PubMed Central

    Jurišić, Sanja; Jurišić, Gordan

    2015-01-01

    Aim The objective of present study was to examine influence of adhesives and methods of enamel pretreatment on the shear bond strength (SBS) of orthodontic brackets. The adhesives used were resin-reinforced glass ionomer cements-GIC (Fuji Ortho LC) and composite resin (Transbond XT). Material and Methods The experimental sample consisted of 80 extracted human first premolars. The sample was divided into four equal groups, and the metal brackets were bonded with different enamel pretreatments by using two adhesives: group A-10% polyacrylic acid; Fuji Ortho LC, group B–37% phosphoric acid; Fuji Ortho LC, group C–self etching primer; Transbond XT, group D–37% phosphoric acid, primer; Transbond XT. SBS of brackets was measured. After debonding of brackets, the adhesive remnant index (ARI) was evaluated. Results After the statistical analysis of the collected data was performed (ANOVA; Sheffe post-hoc test), the results showed that significantly lower SBS of the group B was found in relation to the groups C (p=0.031) and D (p=0.026). The results of ARI were similar in all testing groups and it was not possible to determine any statistically significant difference of the ARI (Chi- square test) between all four experimental groups. Conclusion The conclusion is that the use of composite resins material with appropriate enamel pretreatment according to manufacturer’s recommendation is the “gold standard” for brackets bonding for fixed orthodontic appliances. PMID:27688410

  14. Post retention and post/core shear bond strength of four post systems.

    PubMed

    Stockton, L W; Williams, P T; Clarke, C T

    2000-01-01

    As clinicians we continue to search for a post system which will give us maximum retention while maximizing resistance to root fracture. The introduction of several new post systems, with claims of high retentive and resistance to root fracture values, require that independent studies be performed to evaluate these claims. This study tested the tensile and shear dislodgment forces of four post designs that were luted into roots 10 mm apical of the CEJ. The Para Post Plus (P1) is a parallel-sided, passive design; the Para Post XT (P2) is a combination active/passive design; the Flexi-Post (F1) and the Flexi-Flange (F2) are active post designs. All systems tested were stainless steel. This study compared the test results of the four post designs for tensile and shear dislodgment. All mounted samples were loaded in tension until failure occurred. The tensile load was applied parallel to the long axis of the root, while the shear load was applied at 450 to the long axis of the root. The Flexi-Post (F1) was significantly different from the other three in the tensile test, however, the Para Post XT (P2) was significantly different to the other three in the shear test and had a better probability for survival in the Kaplan-Meier survival function test. Based on the results of this study, our recommendation is for the Para Post XT (P2).

  15. Anxa4 Genes are Expressed in Distinct Organ Systems in Xenopus laevis and tropicalis But are Functionally Conserved

    PubMed Central

    Massé, Karine L; Collins, Robert J; Bhamra, Surinder; Seville, Rachel A

    2007-01-01

    Anxa4 belongs to the multigenic annexin family of proteins which are characterized by their ability to interact with membranes in a calcium-dependent manner. Defined as a marker for polarized epithelial cells, Anxa4 is believed to be involved in many cellular processes but its functions in vivo are still poorly understood. Previously, we cloned Xanx4 in Xenopus laevis (now referred to as anxa4a) and demonstrated its role during organogenesis of the pronephros, providing the first evidence of a specific function for this protein during the development of a vertebrate. Here, we describe the strict conservation of protein sequence and functional domains of anxa4 during vertebrate evolution. We also identify the paralog of anxa4a, anxa4b and show its specific temporal and spatial expression pattern is different from anxa4a. We show that anxa4 orthologs in X. laevis and tropicalis display expression domains in different organ systems. Whilst the anxa4a gene is mainly expressed in the kidney, Xt anxa4 is expressed in the liver. Finally, we demonstrate Xt anxa4 and anxa4a can display conserved function during kidney organogenesis, despite the fact that Xt anxa4 transcripts are not expressed in this domain. This study highlights the divergence of expression of homologous genes during Xenopus evolution and raises the potential problems of using X. tropicalis promoters in X. laevis. PMID:19279706

  16. Shear bond strength of different adhesives tested in accordance with DIN 13990-1/-2 and using various methods of enamel conditioning.

    PubMed

    Richter, C; Jost-Brinkmann, P-G

    2015-03-01

    The purpose of this work was to analyze the shear bond strength (SBS) of different adhesives for orthodontic brackets in accordance with DIN 13990-1/-2, also taking into consideration potential effects arising from different scenarios of enamel conditioning and specimen storage. A total of 390 experiments were performed, with groups of 10 specimens subjected to identical treatments. Three adhesives were tested: Transbond™ XT (3M Unitek, Monrovia, USA), Beauty Ortho Bond (Shofu, Kyoto, Japan), and Fuji Ortho LC (GC Europe, Leuven, Belgium). SBS was evaluated separately at the bracket-adhesive and adhesive-enamel interfaces, as well as the total (enamel-adhesive-bracket) interface. The brackets were metal brackets for upper right central incisors (Discovery® from Dentaurum, Ispringen, Germany). A universal testing machine (Zwick Z010, Ulm, Germany) was used for testing the SBS after 15 min, or after storage in distilled water at 37 °C for 24 h, or after 24 h followed by 500 thermocycles alternating between 5 and 55 °C. Transbond™ XT produced the highest levels of SBS. The least favorable performance was observed with Fuji Ortho LC after enamel conditioning with 10 % polyacrylic acid. Thermocycling did not have a significant influence. Transbond™ XT and Beauty Ortho Bond (but not Fuji Ortho LC) yielded levels of SBS adequate for clinical application (≥ 7 MPa).

  17. Survival of prototype strains of somatic coliphage families in environmental waters and when exposed to UV low-pressure monochromatic radiation or heat.

    PubMed

    Lee, Hee Suk; Sobsey, Mark D

    2011-06-01

    The potential use of specific somatic coliphage taxonomic groups as viral indicators based on their persistence and prevalence in water was investigated. Representative type strains of the 4 major somatic coliphage taxonomic groups were seeded into reagent water and an ambient surface water source of drinking water and the survival of the added phages was measured over 90 days at temperatures of 23-25 and 4 °C. Microviridae (type strain PhiX174), Siphoviridae (type strain Lambda), and Myoviridae (type strain T4) viruses were the most persistent in water at the temperatures tested. The Microviridae (type strain PhiX174) and the Siphoviridae (type strain Lambda) were the most resistant viruses to UV radiation and the Myoviridae (type strain T4) and the Microviridae (type strain PhiX174) were the most resistant viruses to heat. Based on their greater persistence in water over time and their relative resistance to heat and/or UV radiation, the Myoviridae (type strain T4), the Microviridae (type strain PhiX174), and the Siphoviridae (type strain Lambda) were the preferred candidate somatic coliphages as fecal indicator viruses in water, with the Microviridae (type strain PhiX174) the most resistant to these conditions overall. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. [Study on the molecular epidemiology of Streptococcus suis type 2 from healthy pigs in Guangxi].

    PubMed

    Xiong, Yi; Liu, Qi; Qin, Fang-yun; Bai, Yun; Zhu, Wei; Li, Hua-ming; Guo, Jian-gang; Qin, Lun; Pan, Jie; Long, Jian-ming; Chen, Lei

    2007-06-01

    In order to investigate the positive rate of streptococcus suis type 2 and the genes of their suilysin (sly), extracellular protein (epf) and muramidasa-released protein ( mrp) and to understand the antibiotic susceptibility of S. suis type 2. S. suis type 2, isolated from slaughtered healthy pig's tonsil in 10 county area of Guangxi, were identified by Multiplex PCR, and the genes of their sly, epf, mrp and the antimicrobial sensitivity analysis were performed. 1105 strains of Streptococcus including 667 strains of S. suis and 33 strains of S. suis type 2 were detected from 1179 samples. In these S. suis type 2 strains, there were 22 strains of sly + mrp + epf+ type,1 strain of sly + mrp + epf - type, 2 strains of sly - mrp + epf + type, 7 strains of sly - mrp + epf - type and 1 strain of sly - mrp - epf- type. When these strains were subjected to be tested with penicillin, eritrocina, vacocin, gentamycin, specti-nomysin, enraxacin, ciprofloxaxin, cephalothin VI, sulfadiazine sodium, cyantin, mycifradin, amikacin and achromcin, some were found to be resistant to but most strains were susceptible to cephalothin VI, penicillin and enraxacin. There were 31, 29 and 27 strains over medium sensitivity, respectively, but 28 and 27 resistant strains to amikacin and achromcin were found. The positive rate of S. suis type 2 in clinical healthy pigs was low (2.8%) and did not show obvious difference between the counties with or without a history of S. suis infection. All the isolated strains were susceptible to cephalothin VI, but most strains were virulent.

  19. Comparison of microleakage in Class II cavities restored with silorane-based and methacrylate-based composite resins using different restorative techniques over time.

    PubMed

    Khosravi, Kazem; Mousavinasab, Seyed-Mostafa; Samani, Mahsa Sahraneshin

    2015-01-01

    Despite the growing tendency toward tooth-colored restorations in dentistry, polymerization shrinkage and subsequent marginal microleakage remains a problem. The aim of this in vitro study was to compare microleakage between silorane-based and methacrylate-based composite resins at different time intervals and with different restorative techniques. In this in vitro study, 108 sound extracted human molar teeth were used. Mesial and distal proximal class II boxes with dimensions of 1.5 mm depth and 4 mm width were prepared. The gingival margins of all cavities were 1 mm below the cement enamel junction. The teeth were randomly divided into three groups based on test materials. In the first group, the teeth were restored by a nanocomposite (Filtek Z350XT, 3MESPE) and SE Bond adhesive (Kuraray, Japan), in the second group, the teeth were restored with a silorane-based (Filtek P90, 3MESPE) and Filtek P90 Adhesive (3M ESPE, USA) and in the third group, the teeth were restored with a microhybrid posterior composite resin (Filtek P60, 3MESPE) and SE Bond adhesive (Kuraray, Japan). Half of the proximal cavities in each of these three groups were restored in two horizontal layers and the other half in four horizontal layers. After a period of aging (24-h, 3-month and 6-month) in water and then application of 500 thermal cycles, the teeth were immersed for 24-h in 0.5% fuchsin and evaluated under a stereomicroscope at ×36 magnification to evaluate leakage in gingival margin. Data was statistically analyzed using Kruskal-Wallis and Mann-Whitney U-tests. P ≤ 0.05 was considered as significant. In Z350XT statistically significant differences were observed in microleakage in comparison of 24-h and 6-month intervals (P = 0.01) that was higher in 6-month. Comparison of microleakage in P90 and P60 composite resins was also statistically significant and was less in P90. Microleakage was not significantly different between P90 and Z350XT at 24-h. However, this difference was significant at 3-month and 6-month intervals. Differences in microleakage of P60 and Z-350XT composite resins were not statistically significant in all intervals (P = 0.38). P90 showed the lowest microleakage during storage in water. Z350XT had microleakage similar to P90 within 24-h, but after 6-month of storage in water, it showed the highest microleakage among all the groups. The number of layers (2 layers vs. 4 layers) did not result in any differences in microleakage scores of the composite resins (P = 0.42). Water storage times did not result in any significant effect on microleakage of P90 and P60.

  20. Understanding Aprun Use Patterns

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lin, Hwa-Chun Wendy

    2009-05-06

    On the Cray XT, aprun is the command to launch an application to a set of compute nodes reserved through the Application Level Placement Scheduler (ALPS). At the National Energy Research Scientific Computing Center (NERSC), interactive aprun is disabled. That is, invocations of aprun have to go through the batch system. Batch scripts can and often do contain several apruns which either use subsets of the reserved nodes in parallel, or use all reserved nodes in consecutive apruns. In order to better understand how NERSC users run on the XT, it is necessary to associate aprun information with jobs. Itmore » is surprisingly more challenging than it sounds. In this paper, we describe those challenges and how we solved them to produce daily per-job reports for completed apruns. We also describe additional uses of the data, e.g. adjusting charging policy accordingly or associating node failures with jobs/users, and plans for enhancements.« less

  1. [Effects of surface treatment and adhesive application on shear bond strength between zirconia and enamel].

    PubMed

    Li, Yinghui; Wu, Buling; Sun, Fengyang

    2013-03-01

    To evaluate the effects of sandblasting and different orthodontic adhesives on shear bond strength between zirconia and enamel. Zirconia ceramic samples were designed and manufactured for 40 extracted human maxillary first premolars with CAD/CAM system. The samples were randomized into 4 groups for surface treatment with sandblasting and non-treated with adhesives of 3M Transbond XT or Jingjin dental enamel bonding resin. After 24 h of bonded fixation, the shear bond strengths were measured by universal mechanical testing machine and analyzed with factorial variance analysis. The shear bond strength was significantly higher in sandblasting group than in untreated group (P<0.05) and comparable between the two groups with the adhesives of Transbond XT and dental enamel bonding resin (P>0.05). The shear bond strength between zirconia and enamel is sufficient after sandblasting regardless of the application of either adhesive.

  2. Magnon modes and magnon-vortex scattering in two-dimensional easy-plane ferromagnets

    NASA Astrophysics Data System (ADS)

    Ivanov, B. A.; Schnitzer, H. J.; Mertens, F. G.; Wysin, G. M.

    1998-10-01

    We calculate the magnon modes in the presence of a vortex on a circular system, combining analytical calculations in the continuum limit with a numerical diagonalization of the discrete system. The magnon modes are expressed by the S matrix for magnon-vortex scattering, as a function of the parameters and the size of the system and for different boundary conditions. Certain quasilocal translational modes are identified with the frequencies which appear in the trajectory X-->(t) of the vortex center in recent molecular dynamics simulations of the full many-spin model. Using these quasilocal modes we calculate the two parameters of a third-order equation of motion for X-->(t). This equation was recently derived by a collective variable theory and describes very well the trajectories observed in the simulations. Both parameters, the vortex mass and the factor in front of X-->⃛, depend strongly on the boundary conditions.

  3. In vitro cytotoxicity of orthodontic primers.

    PubMed

    D'Antò, Vincenzo; Spagnuolo, Gianrico; Polito, Ilaria; Paduano, Sergio; Ambrosio, Luigi; Valletta, Rosa

    2009-01-01

    The aim of this study was to evaluate the cytotoxicity of four orthodontic primers: Transbond XT and Transbond MIP (3M, USA), Eagle Fluorsure (American Orthodontics, USA) and Ortho Solo (Ormco, USA). Balb 3T3 cells were exposed to different concentrations of primers (0-0.25 mg/ml). Mitochondrial dehydrogenase activity was evaluated by MTT assay and cell necrosis was measured by flow cytometry (propidium iodide staining). All the materials decreased cell viability in a dose related manner. Cytotoxicity of orthodontic primers based on concentrations which caused a 50% decrease of mitochondrial activity was ranked as follows: Transbond XT (45.57 mg/ml) > Eagle Fluorsure (49.27 mg/ml) > Transbond MIP (64.35 mg/ml) > Ortho solo (70.09 mg/ml). Our results suggest that the cytotoxic potencies demonstrated by orthodontic primers might be of clinical relevance since they disturbed cell metabolism and induced cell death in monolayer cultures.

  4. Mitogenic effect contributes to increased virulence of Streptococcus suis sequence type 7 to cause streptococcal toxic shock-like syndrome.

    PubMed

    Zheng, H; Ye, C; Segura, M; Gottschalk, M; Xu, J

    2008-09-01

    Streptococcus suis serotype 2 sequence type 7 strains emerged in 1996 and caused a streptococcal toxic shock-like syndrome in 1998 and 2005 in China. Evidence indicated that the virulence of S. suis sequence type 7 had increased, but the mechanism was unknown. The sequence type 7 strain SC84, isolated from a patient with streptococcal toxic shock-like syndrome during the Sichuan outbreak, and the sequence type 1 strain 31533, a typical highly pathogenic strain isolated from a diseased pig, were used in comparative studies. In this study we show the mechanisms underlying cytokine production differed between the two types of strains. The S. suis sequence type 7 strain SC84 possesses a stronger capacity to stimulate T cells, naive T cells and peripheral blood mononuclear cell proliferation than does S. suis sequence type 1 strain 31533. The T cell response to both strains was dependent upon the presence of antigen-presenting cells. Histo-incompatible antigen-presenting cells were sufficient to provide the accessory signals to naive T cell stimulated by the two strains, indicating that both sequence type 7 and 1 strains possess mitogens; however, the mitogenic effect was different. Therefore, we propose that the difference in the mitogenic effect of sequence type 7 strain SC84 compared with the sequence type 1 strain 31533 of S. suis may be associated with the clinical, epidemiological and microbiological difference, where the ST 7 strains have a larger mitogenic effect.

  5. Mitogenic effect contributes to increased virulence of Streptococcus suis sequence type 7 to cause streptococcal toxic shock-like syndrome

    PubMed Central

    Zheng, H; Ye, C; Segura, M; Gottschalk, M; Xu, J

    2008-01-01

    Streptococcus suis serotype 2 sequence type 7 strains emerged in 1996 and caused a streptococcal toxic shock-like syndrome in 1998 and 2005 in China. Evidence indicated that the virulence of S. suis sequence type 7 had increased, but the mechanism was unknown. The sequence type 7 strain SC84, isolated from a patient with streptococcal toxic shock-like syndrome during the Sichuan outbreak, and the sequence type 1 strain 31533, a typical highly pathogenic strain isolated from a diseased pig, were used in comparative studies. In this study we show the mechanisms underlying cytokine production differed between the two types of strains. The S. suis sequence type 7 strain SC84 possesses a stronger capacity to stimulate T cells, naive T cells and peripheral blood mononuclear cell proliferation than does S. suis sequence type 1 strain 31533. The T cell response to both strains was dependent upon the presence of antigen-presenting cells. Histo-incompatible antigen-presenting cells were sufficient to provide the accessory signals to naive T cell stimulated by the two strains, indicating that both sequence type 7 and 1 strains possess mitogens; however, the mitogenic effect was different. Therefore, we propose that the difference in the mitogenic effect of sequence type 7 strain SC84 compared with the sequence type 1 strain 31533 of S. suis may be associated with the clinical, epidemiological and microbiological difference, where the ST 7 strains have a larger mitogenic effect. PMID:18803762

  6. Differentiation of Salmonella enteritidis phage type 8 strains: evaluation of three additional phage typing systems, plasmid profiles, antibiotic susceptibility patterns, and biotyping.

    PubMed Central

    Stubbs, A D; Hickman-Brenner, F W; Cameron, D N; Farmer, J J

    1994-01-01

    Three additional phage typing systems for Salmonella enteritidis, plasmid analysis, biochemical tests, and antimicrobial susceptibility tests, were used in an attempt to subdivide 30 phage type 8 (phage typing system used by the WHO International Center for Enteric Phage Typing, London, England) isolates. These isolates represented 18 different egg-related outbreaks (21 strains) and 9 reference strains or strains that were not egg-associated. Only 7 of the 30 strains (28%) were subdivided by one or more of the methods used; this included 3 of the 21 strains from egg-related outbreaks. Twenty-seven strains contained a 55-kb plasmid that is associated with S. enteritidis. Of 65 additional phages tested, 2 from the phage typing system obtained from the Pasteur Institute, Paris, France, were useful in differentiating the three strains that lacked the 55-kb plasmid. Although the results obtained for the 21 strains from egg-related outbreaks showed that the strains had minor phenotypic differences, the overall results suggested that the strains may represent a single clone. Studies are planned to test additional phages and other typing methods to see whether strains of phage type 8 can be further differentiated. PMID:8126179

  7. Kimpo-iap K-14, Seoul, Korea. Revised Uniform Summary of Surface Weather Observations (RUSSWO). Parts A-F

    DTIC Science & Technology

    1973-10-30

    10 101 7C 50 34/ 33 1j~ .j . 1111 .11 123 78 ( 32/ 31 2. 5. 2e . 203 20 161 128 30/ 29 4 --- ----- ---- 7- 171 20- 10 28/ 27 1 . 6. 1. c 209 209 182...55ill1.1.11 . l 111111,.f, 5141, 1 ,s , I o 1asS1, ., .1, !11s a,, 1ei 1,I,~ Iit li, [1l s 1 4111 -~ 1111 1ss 1 il mi s~ sIs i, iist aS . asls i II 10 9 8 1 6 5...u o tugfe XT T IT 3 in E 1 i, 77 4K. 10 STATION LOCATION AND INSTRUMENTATION HISTORY UNFR TYPE AT TA:S LOCATION ELEVATION OS 3* OF ,FOCRAPHICAL

  8. Developmental validation of a Nextera XT mitogenome Illumina MiSeq sequencing method for high-quality samples.

    PubMed

    Peck, Michelle A; Sturk-Andreaggi, Kimberly; Thomas, Jacqueline T; Oliver, Robert S; Barritt-Ross, Suzanne; Marshall, Charla

    2018-05-01

    Generating mitochondrial genome (mitogenome) data from reference samples in a rapid and efficient manner is critical to harnessing the greater power of discrimination of the entire mitochondrial DNA (mtDNA) marker. The method of long-range target enrichment, Nextera XT library preparation, and Illumina sequencing on the MiSeq is a well-established technique for generating mitogenome data from high-quality samples. To this end, a validation was conducted for this mitogenome method processing up to 24 samples simultaneously along with analysis in the CLC Genomics Workbench and utilizing the AQME (AFDIL-QIAGEN mtDNA Expert) tool to generate forensic profiles. This validation followed the Federal Bureau of Investigation's Quality Assurance Standards (QAS) for forensic DNA testing laboratories and the Scientific Working Group on DNA Analysis Methods (SWGDAM) validation guidelines. The evaluation of control DNA, non-probative samples, blank controls, mixtures, and nonhuman samples demonstrated the validity of this method. Specifically, the sensitivity was established at ≥25 pg of nuclear DNA input for accurate mitogenome profile generation. Unreproducible low-level variants were observed in samples with low amplicon yields. Further, variant quality was shown to be a useful metric for identifying sequencing error and crosstalk. Success of this method was demonstrated with a variety of reference sample substrates and extract types. These studies further demonstrate the advantages of using NGS techniques by highlighting the quantitative nature of heteroplasmy detection. The results presented herein from more than 175 samples processed in ten sequencing runs, show this mitogenome sequencing method and analysis strategy to be valid for the generation of reference data. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Effect of Energy Drinks on Discoloration of Silorane and Dimethacrylate-Based Composite Resins.

    PubMed

    Ahmadizenouz, Ghazaleh; Esmaeili, Behnaz; Ahangari, Zohreh; Khafri, Soraya; Rahmani, Aghil

    2016-08-01

    This study aimed to assess the effects of two energy drinks on color change (ΔE) of two methacrylate-based and a silorane-based composite resin after one week and one month. Thirty cubic samples were fabricated from Filtek P90, Filtek Z250 and Filtek Z350XT composite resins. All the specimens were stored in distilled water at 37°C for 24 hours. Baseline color values (L*a*b*) of each specimen were measured using a spectrophotometer according to the CIEL*a*b* color system. Ten randomly selected specimens from each composite were then immersed in the two energy drinks (Hype, Red Bull) and artificial saliva (control) for one week and one month. Color was re-assessed after each storage period and ΔE values were calculated. The data were analyzed using the Kruskal Wallis and Mann-Whitney U tests. Filtek Z250 composite showed the highest ΔE irrespective of the solutions at both time points. After seven days and one month, the lowest ΔE values were observed in Filtek Z350XT and Filtek P90 composites immersed in artificial saliva, respectively. The ΔE values of Filtek Z250 and Z350XT composites induced by Red Bull and Hype energy drinks were not significantly different. Discoloration of Filtek P90 was higher in Red Bull energy drink at both time points. Prolonged immersion time in all three solutions increased ΔE values of all composites. However, the ΔE values were within the clinically acceptable range (<3.3) at both time points.

  10. Standardized methodology for transfemoral transcatheter aortic valve replacement with the Edwards Sapien XT valve under fluoroscopy guidance.

    PubMed

    Kasel, Albert M; Shivaraju, Anupama; Schneider, Stephan; Krapf, Stephan; Oertel, Frank; Burgdorf, Christof; Ott, Ilka; Sumer, Christian; Kastrati, Adnan; von Scheidt, Wolfgang; Thilo, Christian

    2014-09-01

    To provide a simplified, standardized methodology for a successful transfemoral transcatheter aortic valve replacement (TAVR) procedure with the Sapien XT valve in patients with severe aortic stenosis (AS). TAVR is currently reserved for patients with severe, symptomatic AS who are inoperable or at high operative risk. In many institutions, TAVR is performed under general anesthesia with intubation or with conscious sedation. In addition, many institutions still use transesophageal echo (TEE) during the procedure for aortic root angulations and positioning of the valve prior to implantation. Methods. We enrolled 100 consecutive patients (mean age, 80 ± 7 years; range, 50-94 years; female n=59) with severe symptomatic AS. Annulus measurements were based on computed tomography angiograms. All patients underwent fluoroscopy-guided transfemoral TAVR with little to no sedation and without simultaneous TEE. TAVR was predominantly performed with the use of local and central analgesics; only 36% of our cohort received conscious sedation. Procedural success of TAVR was 99%. Transthoracic echocardiography before discharge excluded aortic regurgitation (AR) >2 in all patients (AR >1; n=6). In-hospital stroke rate was 6%. The vessel closure system was successfully employed in 96%. Major vascular complication rate was 1%. The 30-day mortality was 2%. Fluoroscopy-guided TAVR with the use of just analgesics with or without conscious sedation is safe and effective, and this potentially enables a more time-effective and cost-effective procedure. This paper provides simplified, stepwise guidance on how to perform transfemoral TAVR with the Sapien XT valve.

  11. Early outcomes of percutaneous pulmonary valve implantation using the Edwards SAPIEN XT transcatheter heart valve system.

    PubMed

    Haas, Nikolaus A; Carere, Ronald Giacomo; Kretschmar, Oliver; Horlick, Eric; Rodés-Cabau, Josep; de Wolf, Daniël; Gewillig, Marc; Mullen, Michael; Lehner, Anja; Deutsch, Cornelia; Bramlage, Peter; Ewert, Peter

    2018-01-01

    Patients with congenital or acquired heart defects affecting the pulmonary valve and right ventricular outflow tract (RVOT) commonly require multiple surgical interventions, resulting in significant morbidity. A less invasive alternative is percutaneous pulmonary valve implantation (PPVI). Though studies have previously reported the safety and efficacy of the early generation transcatheter heart valves (THVs), data on more recent devices are severely lacking. We performed a multinational, multicentre, retrospective, observational registry analysis of patients who underwent PPVI using the Edwards SAPIEN XT THV. Of the 46 patients that were enrolled, the majority had tetralogy of Fallot as the underlying diagnosis (58.7%), and stentless xenograft as the most common RVOT anatomy (34.8%). Procedural success rate was high (93.5%), with a low frequency of periprocedural complications and adverse events (6.5% and 10.9%, respectively). At 30days post-procedure, NYHA class had improved significantly (90.6% were at NYHA I or II). The rate of moderate/severe pulmonary regurgitation had decreased from 76.1% at baseline to 5.0% at 30days, and the calculated peak systolic gradient had decreased from 45.2 (SD±21.3) mmHg to 16.4 (SD±8.0) mmHg, with these values remaining low up to 2years. The data suggest the efficacy and safety of the SAPIEN XT THV in PPVI in common anatomies in patients with conduits, as well as those with native pulmonary valves or transannular patches. Continued data collection is necessary to verify long-term findings. CLINICALTRIALS. NCT02302131. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Ada To X-Window Bindings

    NASA Technical Reports Server (NTRS)

    Souleles, Dean

    1993-01-01

    Ada to X-Window Bindings computer program developed to provide Ada programmers with complete interfaces to Xt Intrinsics and OSF Motif toolkits. Provides "Ada view" of some mostly C-language programming libraries. Package of software written in Ada and C languages.

  13. The molecular phylogenic tree of the genus Trichinella constructed from isozyme patterns.

    PubMed

    Fukumoto, S; Nagai, D; Yazaki, S; Kamo, H; Yamaguchi, T

    1988-01-01

    Six zymograms were compared for extracts of muscle-stage larvae of the seven Trichinella isolates, using isoelectric focusing in polyacrylamide gels. The isozyme patterns of acid phosphatase among them fell into four types. T. pseudospiralis from a raccoon and the Polar strain from a polar bear formed type 1 and type 2, respectively. The Iwasaki strain from a Japanese black bear and the Yamagata strain from a raccoon dog, both from Japan, were type 3. Type 4 consisted of three remaining strains, viz. the Polish strain from a wild pig, the USA strain from a pig, and the Thai strain from a human case, all of which have similar infectivity to pigs. The isozyme patterns of esterase 1, beta-N-acetylglucosaminidase, and peptidase were similar in types 2 and 3. Those of esterase D were common to types 2-4 but not to type 1. In the zymogram of mannosephosphate isomerase, types 2-4 but not type 1 had one common band, whereas in the other bands type 2 was markedly distinguished from types 3 and 4. In the present study, the molecular phylogenic tree was constructed for the first time on the basis of our present and previous electrophoretic data by the use of cluster analysis, and the evolutionary process was considered as follows: T. pseudospiralis (type 1) and T. spiralis (the common ancestor of types 2-4) were initially separated. Next, the common ancestor of the strains from wild carnivores (types 2 and 3) and type 4 were separated. Finally, the Polar strain (type 2) and the Japanese strain (type 3) were separated.

  14. Metrics for the Human Proteome Project 2016: Progress on Identifying and Characterizing the Human Proteome, Including Post-Translational Modifications.

    PubMed

    Omenn, Gilbert S; Lane, Lydie; Lundberg, Emma K; Beavis, Ronald C; Overall, Christopher M; Deutsch, Eric W

    2016-11-04

    The HUPO Human Proteome Project (HPP) has two overall goals: (1) stepwise completion of the protein parts list-the draft human proteome including confidently identifying and characterizing at least one protein product from each protein-coding gene, with increasing emphasis on sequence variants, post-translational modifications (PTMs), and splice isoforms of those proteins; and (2) making proteomics an integrated counterpart to genomics throughout the biomedical and life sciences community. PeptideAtlas and GPMDB reanalyze all major human mass spectrometry data sets available through ProteomeXchange with standardized protocols and stringent quality filters; neXtProt curates and integrates mass spectrometry and other findings to present the most up to date authorative compendium of the human proteome. The HPP Guidelines for Mass Spectrometry Data Interpretation version 2.1 were applied to manuscripts submitted for this 2016 C-HPP-led special issue [ www.thehpp.org/guidelines ]. The Human Proteome presented as neXtProt version 2016-02 has 16,518 confident protein identifications (Protein Existence [PE] Level 1), up from 13,664 at 2012-12, 15,646 at 2013-09, and 16,491 at 2014-10. There are 485 proteins that would have been PE1 under the Guidelines v1.0 from 2012 but now have insufficient evidence due to the agreed-upon more stringent Guidelines v2.0 to reduce false positives. neXtProt and PeptideAtlas now both require two non-nested, uniquely mapping (proteotypic) peptides of at least 9 aa in length. There are 2,949 missing proteins (PE2+3+4) as the baseline for submissions for this fourth annual C-HPP special issue of Journal of Proteome Research. PeptideAtlas has 14,629 canonical (plus 1187 uncertain and 1755 redundant) entries. GPMDB has 16,190 EC4 entries, and the Human Protein Atlas has 10,475 entries with supportive evidence. neXtProt, PeptideAtlas, and GPMDB are rich resources of information about post-translational modifications (PTMs), single amino acid variants (SAAVSs), and splice isoforms. Meanwhile, the Biology- and Disease-driven (B/D)-HPP has created comprehensive SRM resources, generated popular protein lists to guide targeted proteomics assays for specific diseases, and launched an Early Career Researchers initiative.

  15. Application of Strep-Tactin XT for affinity purification of Twin-Strep-tagged CB2, a G protein-coupled cannabinoid receptor.

    PubMed

    Yeliseev, Alexei; Zoubak, Lioudmila; Schmidt, Thomas G M

    2017-03-01

    Human cannabinoid receptor CB 2 belongs to the class A of G protein-coupled receptor (GPCR). CB 2 is predominantly expressed in membranes of cells of immune origin and is implicated in regulation of metabolic pathways of inflammation, neurodegenerative disorders and pain sensing. High resolution structural studies of CB 2 require milligram quantities of purified, structurally intact protein. While we previously reported on the methodology for expression of the recombinant CB 2 and its stabilization in a functional state, here we describe an efficient protocol for purification of this protein using the Twin-Strep-tag/Strep-Tactin XT system. To improve the affinity of interaction of the recombinant CB 2 with the resin, the double repeat of the Strep-tag (a sequence of eight amino acids WSHPQFEK), named the Twin-Strep-tag was attached either to the N- or C-terminus of CB 2 via a short linker, and the recombinant protein was expressed in cytoplasmic membranes of E. coli as a fusion with the N-terminal maltose binding protein (MBP). The CB 2 was isolated at high purity from dilute solutions containing high concentrations of detergents, glycerol and salts, by capturing onto the Strep-Tactin XT resin, and was eluted from the resin under mild conditions upon addition of biotin. Surface plasmon resonance studies performed on the purified protein demonstrate the high affinity of interaction between the Twin-Strep-tag fused to the CB 2 and Strep-Tactin XT with an estimated Kd in the low nanomolar range. The affinity of binding did not vary significantly in response to the position of the tag at either N- or C-termini of the fusion. The binding capacity of the resin was several-fold higher for the tag located at the N-terminus of the protein as opposed to the C-terminus- or middle of the fusion. The variation in the length of the linker between the double repeats of the Strep-tag from 6 to 12 amino acid residues did not significantly affect the binding. The novel purification protocol reported here enables efficient isolation of a recombinant GPCR expressed at low titers in host cells. This procedure is suitable for preparation of milligram quantities of stable isotope-labelled receptor for high-resolution NMR studies. Published by Elsevier Inc.

  16. Prevalent genotypes of Toxoplasma gondii in pregnant women and patients from Crete and Cyprus.

    PubMed

    Messaritakis, Ippokratis; Detsika, Maria; Koliou, Maria; Sifakis, Stavros; Antoniou, Maria

    2008-08-01

    Molecular genotyping has been used to characterize Toxoplasma gondii strains into the three clonal lineages known as types I, II, and III. To characterize T. gondii strains from Greece and Cyprus, polymerase chain reaction-restriction fragment length polymorphism analysis on the GRA6 gene was performed directly on 20 clinical samples from 18 humans (11 pregnant women, six patients with lymphadenopathy, and one patient positive for human immunodeficiency virus) and two rats. Characterization of T. gondii types was performed after digestion of amplified products with Mse I. The 20 strains were characterized as type II (20%) and type III (80%). Of these strains, 19 originated from the island of Crete (4 strains type II and 15 strains type III), and 1 from the island of Cyprus (type III). Although both type II and type III strains were found, type III was the most prevalent in Crete.

  17. Combined use of ribotyping, PFGE typing and IS431 typing in the discrimination of nosocomial strains of methicillin-resistant Staphylococcus aureus.

    PubMed

    Yoshida, T; Kondo, N; Hanifah, Y A; Hiramatsu, K

    1997-01-01

    We have previously reported the phenotypic characterization of methicillin-resistant Staphylococcus aureus (MRSA) clinical strains isolated in Malaya University Hospital in the period 1987 to 1989 using antibiogram, coagulase typing, plasmid profiles, and phage typing. Here, we report the analysis of the same strains with three genotyping methods; ribotyping, pulsed-field gel electrophoresis (PFGE) typing, and IS431 typing (a restriction enzyme fragment length polymorphism analysis using an IS431 probe). Ribotyping could discriminate 46 clinical MRSA strains into 5 ribotypes, PFGE typing into 22 types, and IS431 typing into 15 types. Since the differences of the three genotyping patterns from strain to strain were quite independent from one another, the combined use of the three genotyping methods could discriminate 46 strains into 39 genotypes. Thus, the powerful discriminatory ability of the combination was demonstrated.

  18. Genetic Characterization and Comparison of Clostridium botulinum Isolates from Botulism Cases in Japan between 2006 and 2011

    PubMed Central

    Sekizuka, Tsuyoshi; Yamamoto, Akihiko; Iwaki, Masaaki; Komiya, Takako; Hatakeyama, Takashi; Nakajima, Hiroshi; Takahashi, Motohide; Kuroda, Makoto; Shibayama, Keigo

    2014-01-01

    Genetic characterization was performed for 10 group I Clostridium botulinum strains isolated from botulism cases in Japan between 2006 and 2011. Of these, 1 was type A, 2 were type B, and 7 were type A(B) {carrying a silent bont/B [bont/(B)] gene} serotype strains, based on botulinum neurotoxin (BoNT) production. The type A strain harbored the subtype A1 BoNT gene (bont/A1), which is associated with the ha gene cluster. The type B strains carried bont/B5 or bont/B6 subtype genes. The type A(B) strains carried bont/A1 identical to that of type A(B) strain NCTC2916. However, bont/(B) genes in these strains showed single-nucleotide polymorphisms (SNPs) among strains. SNPs at 2 nucleotide positions of bont/(B) enabled classification of the type A(B) strains into 3 groups. Pulsed-field gel electrophoresis (PFGE) and multiple-locus variable-number tandem-repeat analysis (MLVA) also provided consistent separation results. In addition, the type A(B) strains were separated into 2 lineages based on their plasmid profiles. One lineage carried a small plasmid (5.9 kb), and another harbored 21-kb plasmids. To obtain more detailed genetic information about the 10 strains, we sequenced their genomes and compared them with 13 group I C. botulinum genomes in a database using whole-genome SNP analysis. This analysis provided high-resolution strain discrimination and enabled us to generate a refined phylogenetic tree that provides effective traceability of botulism cases, as well as bioterrorism materials. In the phylogenetic tree, the subtype B6 strains, Okayama2011 and Osaka05, were distantly separated from the other strains, indicating genomic divergence of subtype B6 strains among group I strains. PMID:25192986

  19. Comparative studies on soluble protein profiles and isozyme patterns of seven Trichinella isolates.

    PubMed

    Fukumoto, S; Takechi, M; Kamo, H; Yamaguchi, T

    1987-01-01

    Soluble protein profiles and isozyme patterns of eight enzymes were compared for extracts of muscle stage larvae of the seven Trichinella isolates, using isoelectric focusing in polyacrylamide gel. Soluble protein profiles and isozyme patterns of four enzymes: malic enzyme, glucosephosphate isomerase, phosphoglucomutase, superoxide dismutase of them were clearly divided into four types. T. pseudospiralis from a racoon and the Polar strain from a polar bear formed type 1 and type 2. The Iwasaki strain from a Japanese black bear and the Yamagata strain from a racoon dog, both from Japan, were type 3. Type 4 consisted of three remaining strains, the Polish strain from a wild pig, the USA strain from a pig and the Thai strain from a human case, which have similar infectivities to pigs. The Thai strain varied a bit electrophoretically from other members of type 4. Zymograms of adenylate kinase and malate dehydrogenase were similar in types 2 and 3. The 6-phosphogluconate dehydrogenase zymogram of type 3, similar to that of type 4, was different from that of type 2. It is assumed from the data that type 3 (Japanese strain) was genetically intermediate to types 2 and 4. T. pseudospiralis and the Polar strain had a common main isozyme of 6-phosphogluconate dehydrogenase. The zymogram of lactate dehydrogenase was common except for T. pseudospiralis.

  20. Live Streptococcus suis type 5 strain XS045 provides cross-protection against infection by strains of types 2 and 9.

    PubMed

    Jiang, Xiaowu; Yang, Yunkai; Zhu, Lexin; Gu, Yuanxing; Shen, Hongxia; Shan, Ying; Li, Xiaoliang; Wu, Jiusheng; Fang, Weihuan

    2016-12-12

    Streptococcus suis is one of the common pathogens causing diseases in pigs and covers 35 serotypes with the type 2 strains being more pathogenic and zoonotic. Existing inactivated or subunit vaccines, in clinical use or under trial, could not provide cross protection against other serotypes. We identified a natural low-virulence S. suis type 5 strain XS045 as a live vaccine candidate because it is highly adhesive to the cultured HEp-2 cells, but with no apparent pathogenicity in mice and piglets. We further demonstrate that subcutaneous administration of the live XS045 strain to mice induced high antibody responses and was able to provide cross protection against challenges by a type 2 strain HA9801 (100% protection) and a type 9 strain JX13 (85% protection). Induction of high-titer antibodies with opsonizing activity as well as their cross-reactivity to surface proteins of the types 2 and 9 strains and anti-adhesion effect could be the mechanisms of cross protection. This is the first report that a live vaccine candidate S. suis type 5 strain could induce cross-protection against strains of types 2 and 9. This candidate strain is to be further examined for safety in pigs of different ages and breeds as well as for its protection against other serotypes or other strains of the type 2, a serotype of particular importance from public health concern. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Colony Dimorphism in Bradyrhizobium Strains

    PubMed Central

    Sylvester-Bradley, Rosemary; Thornton, Philip; Jones, Peter

    1988-01-01

    Ten isolates of Bradyrhizobium spp. which form two colony types were studied; the isolates originated from a range of legume species. The two colony types differed in the amount of gum formed or size or both, depending on the strain. Whole 7-day-old colonies of each type were subcultured to determine the proportion of cells which had changed to the other type. An iterative computerized procedure was used to determine the rate of switching per generation between the two types and to predict proportions reached at equilibrium for each strain. The predicted proportions of the wetter (more gummy) or larger colony type at equilibrium differed significantly between strains, ranging from 0.9999 (strain CIAT 2383) to 0.0216 (strain CIAT 2469), because some strains switched faster from dry to wet (or small to large) and others switched faster from wet to dry (or large to small). Predicted equilibrium was reached after about 140 generations in strain USDA 76. In all but one strain (CIAT 3030) the growth rate of the wetter colony type was greater than or similar to that of the drier type. The mean difference in generation time between the two colony types was 0.37 h. Doubling times calculated for either colony type after 7 days of growth on the agar surface ranged from 6.0 to 7.3 h. The formation of two persistent colony types by one strain (clonal or colony dimorphism) may be a common phenomenon among Bradyrhizobium strains. Images PMID:16347599

  2. Types of strain among family members of individuals with autism spectrum disorder across the lifespan.

    PubMed

    Shivers, Carolyn M; Krizova, Katarina; Lee, Gloria K

    2017-09-01

    Although increased caregiver strain is often found among family caregivers of individuals with autism spectrum disorder, it is still unclear as to how different types of strain relate to amount and types of caregiving across the lifespan. The present study examined different types of strain (i.e. subjective internalized strain, subjective externalized strain, and objective strain) and how such strain relates to the amount of caregiving responsibilities. Data was collected via online survey from a sample of 193 family caregivers of individuals with ASD from the United States, Canada, and the Republic of Ireland. Participants completed measures of strain and caregiving responsibilities, as well as coping, demographics, and services needed and received by the individual with ASD. Caregivers reported higher levels of objective strain than subjective, and caregiving responsibility was related to objective and subjective internalized strain. Coping style was strongly correlated with all types of strain, and unmet service needs were significantly related to objective and subjective internalized strain. Caregiving behaviors were only related to objective strain. The present results indicate that, although caregiving responsibility is related to objective and subjective internalized strain, the relationship is perhaps not as strong as the relationship between coping mechanisms and strain. Future research is needed to understand different types of strain and develop strategies to help caregivers. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. [Use of ITS and ISSR markers in the molecular characterisation of Pleurotus djamor hybrid strains].

    PubMed

    Aguilar Doroteo, Leticia; Zárate Segura, Paola Berenice; Villanueva Arce, Ramón; Yáñez Fernández, Jorge; Garín Aguilar, María Eugenia; Guadarrama Mendoza, Paula Cecilia; Valencia Del Toro, Gustavo

    Molecular characterisation of wild type Pleurotus species is important for germplasm conservation and its further use for genetic improvement. No molecular studies have been performed with monokaryons used for producing hybrid strains, either with the reconstituted strains obtained by pairing those monokaryons. The molecular characterisation of parental dikaryons, hybrid, and reconstituted strains as well as monokaryotic strains, is therefore of utmost importance. To carry out the molecular identification of Pleurotus djamor strains, i.e. dikaryotic wild type strains, hybrid strains, and the monokaryotic strains used for the hybrid formation. Five wild type strains of P. djamor from different states in Mexico were collected and molecularly identified by sequencing the ITS1-5.8-ITS2 region using ITS1 and ITS4 universal oligonucleotides. Four hybrid strains were obtained by pairing neohaplonts of two wild type strains selected. Six ISSR markers were used for the molecular characterisation of monokaryotic and dikaryotic strains. Using the ITS markers, an amplified product of 700bp was obtained in five wild type strains, with a 99-100% similarity with P. djamor. A total of 95 fragments were obtained using the ISSR markers, with 99% of polymorphism. Wild type strains were identified as P. djamor, and were clearly grouped with Mexican strains from other states of Mexico. ISSR markers allowed the generation of polymorphic bands in monokaryotic and dikaryotic strains, splitting both types of strains. The high degree of polymorphism indicates the genetic diversity of P. djamor, an advantage in mushroom production and in the improving of the species. Copyright © 2017 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.

  4. On the nonlinear feedback loop and energy cycle of the non-dissipative Lorenz model

    NASA Astrophysics Data System (ADS)

    Shen, B.-W.

    2014-04-01

    In this study, we discuss the role of the nonlinear terms and linear (heating) term in the energy cycle of the three-dimensional (X-Y-Z) non-dissipative Lorenz model (3D-NLM). (X, Y, Z) represent the solutions in the phase space. We first present the closed-form solution to the nonlinear equation d2 X/dτ2+ (X2/2)X = 0, τ is a non-dimensional time, which was never documented in the literature. As the solution is oscillatory (wave-like) and the nonlinear term (X2) is associated with the nonlinear feedback loop, it is suggested that the nonlinear feedback loop may act as a restoring force. We then show that the competing impact of nonlinear restoring force and linear (heating) force determines the partitions of the averaged available potential energy from Y and Z modes, respectively, denoted as APEY and APEZ. Based on the energy analysis, an energy cycle with four different regimes is identified with the following four points: A(X, Y) = (0,0), B = (Xt, Yt), C = (Xm, Ym), and D = (Xt, -Yt). Point A is a saddle point. The initial perturbation (X, Y, Z) = (0, 1, 0) gives (Xt, Yt) = ( 2σr , r) and (Xm, Ym) = (2 σr , 0). σ is the Prandtl number, and r is the normalized Rayleigh number. The energy cycle starts at (near) point A, A+ = (0, 0+) to be specific, goes through B, C, and D, and returns back to A, i.e., A- = (0,0-). From point A to point B, denoted as Leg A-B, where the linear (heating) force dominates, the solution X grows gradually with { KE↑, APEY↓, APEZ↓}. KE is the averaged kinetic energy. We use the upper arrow (↑) and down arrow (↓) to indicate an increase and decrease, respectively. In Leg B-C (or C-D) where nonlinear restoring force becomes dominant, the solution X increases (or decreases) rapidly with KE↑, APEY↑, APEZ↓ (or KE↓, APEY↓, APEZ↑). In Leg D-A, the solution X decreases slowly with {KE↓, APEY↑, APEZ↑ }. As point A is a saddle point, the aforementioned cycle may be only half of a "big" cycle, displaying the wing pattern of a glasswinged butterfly, and the other half cycle is antisymmetric with respect to the origin, namely B = (-Xt, -Yt), C = (-Xm, 0), and D = (-Xt, Yt).

  5. Phylogenomic Study of Burkholderia glathei-like Organisms, Proposal of 13 Novel Burkholderia Species and Emended Descriptions of Burkholderia sordidicola, Burkholderia zhejiangensis, and Burkholderia grimmiae

    PubMed Central

    Peeters, Charlotte; Meier-Kolthoff, Jan P.; Verheyde, Bart; De Brandt, Evie; Cooper, Vaughn S.; Vandamme, Peter

    2016-01-01

    Partial gyrB gene sequence analysis of 17 isolates from human and environmental sources revealed 13 clusters of strains and identified them as Burkholderia glathei clade (BGC) bacteria. The taxonomic status of these clusters was examined by whole-genome sequence analysis, determination of the G+C content, whole-cell fatty acid analysis and biochemical characterization. The whole-genome sequence-based phylogeny was assessed using the Genome Blast Distance Phylogeny (GBDP) method and an extended multilocus sequence analysis (MLSA) approach. The results demonstrated that these 17 BGC isolates represented 13 novel Burkholderia species that could be distinguished by both genotypic and phenotypic characteristics. BGC strains exhibited a broad metabolic versatility and developed beneficial, symbiotic, and pathogenic interactions with different hosts. Our data also confirmed that there is no phylogenetic subdivision in the genus Burkholderia that distinguishes beneficial from pathogenic strains. We therefore propose to formally classify the 13 novel BGC Burkholderia species as Burkholderia arvi sp. nov. (type strain LMG 29317T = CCUG 68412T), Burkholderia hypogeia sp. nov. (type strain LMG 29322T = CCUG 68407T), Burkholderia ptereochthonis sp. nov. (type strain LMG 29326T = CCUG 68403T), Burkholderia glebae sp. nov. (type strain LMG 29325T = CCUG 68404T), Burkholderia pedi sp. nov. (type strain LMG 29323T = CCUG 68406T), Burkholderia arationis sp. nov. (type strain LMG 29324T = CCUG 68405T), Burkholderia fortuita sp. nov. (type strain LMG 29320T = CCUG 68409T), Burkholderia temeraria sp. nov. (type strain LMG 29319T = CCUG 68410T), Burkholderia calidae sp. nov. (type strain LMG 29321T = CCUG 68408T), Burkholderia concitans sp. nov. (type strain LMG 29315T = CCUG 68414T), Burkholderia turbans sp. nov. (type strain LMG 29316T = CCUG 68413T), Burkholderia catudaia sp. nov. (type strain LMG 29318T = CCUG 68411T) and Burkholderia peredens sp. nov. (type strain LMG 29314T = CCUG 68415T). Furthermore, we present emended descriptions of the species Burkholderia sordidicola, Burkholderia zhejiangensis and Burkholderia grimmiae. The GenBank/EMBL/DDBJ accession numbers for the 16S rRNA and gyrB gene sequences determined in this study are LT158612-LT158624 and LT158625-LT158641, respectively. PMID:27375597

  6. Proteome profiling of virus-host interactions of wild type and attenuated measles virus strains.

    PubMed

    Billing, Anja M; Kessler, Julia R; Revets, Dominique; Sausy, Aurélie; Schmitz, Stephanie; Barra, Claire; Muller, Claude P

    2014-08-28

    Quantitative gel-based proteomics (2D DIGE coupled to MALDI-TOF/TOF MS) has been used to investigate the effects of different measles virus (MV) strains on the host cell proteome. A549/hSLAM cells were infected either with wild type MV strains, an attenuated vaccine or a multiple passaged Vero cell adapted strain. By including interferon beta treatment as a control it was possible to distinguish between the classical antiviral response and changes induced specifically by the different strains. Of 38 differentially expressed proteins in total (p-value ≤0.05, fold change ≥2), 18 proteins were uniquely modulated following MV infection with up to 9 proteins specific per individual strain. Interestingly, wt strains displayed distinct protein patterns particularly during the late phase of infection. Proteins were grouped into cytoskeleton, metabolism, transcription/translation, immune response and mitochondrial proteins. Bioinformatics analysis revealed mostly changes in proteins regulating cell death and apoptosis. Surprisingly, wt strains affected the cytokeratin system much stronger than the vaccine strain. To our knowledge, this is the first study on the MV-host proteome addressing interstrain differences. In the present study we investigated the host cell proteome upon measles virus (MV) infection. The novelty about this study is the side-by side comparison of different strains from the same virus, which has not been done at the proteome level for any other virus including MV. We used different virus strains including a vaccine strain, wild type isolates derived from MV-infected patients as well as a Vero cell adapted strain, which serves as an intermediate between vaccine and wild type strain. We observed differences between vaccine and wild type strains as well as common features between different wild type strains. Perhaps one of the most surprising findings was that differences did not only occur between wild type and vaccine or Vero cell adapted strains but also between different wild type strains. In fact our study suggests that besides the cytokeratin and the IFN system wild type viruses seem to differ as much among each other than from vaccine strains. Thus our results are suggestive of complex and diverse virus-host interactions which differ considerably between different wild type strains. Our data indicate that interstrain differences are prominent and have so far been neglected by proteomics studies. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Heliport noise model (HNM) version 1 user's guide

    DOT National Transportation Integrated Search

    1988-02-01

    This document contains the instructions to execute the Heliport Noise Model (HNM), Version 1. HNM Version 1 is a computer tool for determining the total impact of helicopter noise at and around heliports. The model runs on IBM PC/XT/AT personal compu...

  8. UNCERTAINTY IN SCALING NUTRIENT EXPORT COEFFICIENTS

    EPA Science Inventory

    The Innov-X XT400 portable XRF analyzer features a miniature, rugged x-ray tube excitation source for analyzing a wide variety of elements and sample materials, including alloys, environmental solids, and other analytical samples. The x-ray tube source and Light Element Analysis...

  9. Inter- and Intra-subtype genotypic differences that differentiate Mycobacterium avium subspecies paratuberculosis strains

    PubMed Central

    2012-01-01

    Background Mycobacterium avium subspecies paratuberculosis (Map) is the aetiological agent of Johne’s disease or paratuberculosis and is included within the Mycobacterium avium complex (MAC). Map strains are of two major types often referred to as ‘Sheep’ or ‘S-type’ and ‘Cattle’ or ‘C-type’. With the advent of more discriminatory typing techniques it has been possible to further classify the S-type strains into two groups referred to as Type I and Type III. This study was undertaken to genotype a large panel of S-type small ruminant isolates from different hosts and geographical origins and to compare them with a large panel of well documented C-type isolates to assess the genetic diversity of these strain types. Methods used included Mycobacterial Interspersed Repetitive Units - Variable-Number Tandem Repeat analysis (MIRU-VNTR), analysis of Large Sequence Polymorphisms by PCR (LSP analysis), Single Nucleotide Polymorphism (SNP) analysis of gyr genes, Pulsed-Field Gel Electrophoresis (PFGE) and Restriction Fragment Length Polymorphism analysis coupled with hybridization to IS900 (IS900-RFLP) analysis. Results The presence of LSPA4 and absence of LSPA20 was confirmed in all 24 Map S-type strains analysed. SNPs within the gyr genes divided the S-type strains into types I and III. Twenty four PFGE multiplex profiles and eleven different IS900-RFLP profiles were identified among the S-type isolates, some of them not previously published. Both PFGE and IS900-RFLP segregated the S-type strains into types I and III and the results concurred with those of the gyr SNP analysis. Nine MIRU-VNTR genotypes were identified in these isolates. MIRU-VNTR analysis differentiated Map strains from other members of Mycobacterium avium Complex, and Map S-type from C-type but not type I from III. Pigmented Map isolates were found of type I or III. Conclusion This is the largest panel of S-type strains investigated to date. The S-type strains could be further divided into two subtypes, I and III by some of the typing techniques (IS900-RFLP, PFGE and SNP analysis of the gyr genes). MIRU-VNTR did not divide the strains into the subtypes I and III but did detect genetic differences between isolates within each of the subtypes. Pigmentation is not exclusively associated with type I strains. PMID:23164429

  10. Ogataea pignaliae sp. nov., the teleomorph of Candida pignaliae.

    PubMed

    Péter, Gábor; Tornai-Lehoczki, Judit; Dlauchy, Dénes

    2010-10-01

    Six ascosporulating Candida pignaliae strains were isolated from epigeal plant parts in Hungary. They share identical D1/D2 LSU rRNA gene sequences with the type strain of C. pignaliae, and the physiological characteristics investigated are also very similar to that of the type strain. The only substantial difference compared to the type strain of C. pignaliae is their ability to assimilate β-glucosides (cellobiose, salicin and arbutin). The majority of the isolation sources of the strains reported in this study have the common feature of containing tannic acid, while the type strain of C. pignaliae was recovered from tanning fluid. We were able to induce ascosporulation also in the type strain of C. pignaliae. Therefore, Ogataea pignaliae Péter, Tornai-Lehoczki & Dlauchy sp. nov. is proposed as the teleomorph of C. pignaliae (F. H. Jacob) S. A. Meyer & Yarrow. The type strain is CBS 6071(T).

  11. Sample-to-sample fluctuations of power spectrum of a random motion in a periodic Sinai model.

    PubMed

    Dean, David S; Iorio, Antonio; Marinari, Enzo; Oshanin, Gleb

    2016-09-01

    The Sinai model of a tracer diffusing in a quenched Brownian potential is a much-studied problem exhibiting a logarithmically slow anomalous diffusion due to the growth of energy barriers with the system size. However, if the potential is random but periodic, the regime of anomalous diffusion crosses over to one of normal diffusion once a tracer has diffused over a few periods of the system. Here we consider a system in which the potential is given by a Brownian bridge on a finite interval (0,L) and then periodically repeated over the whole real line and study the power spectrum S(f) of the diffusive process x(t) in such a potential. We show that for most of realizations of x(t) in a given realization of the potential, the low-frequency behavior is S(f)∼A/f^{2}, i.e., the same as for standard Brownian motion, and the amplitude A is a disorder-dependent random variable with a finite support. Focusing on the statistical properties of this random variable, we determine the moments of A of arbitrary, negative, or positive order k and demonstrate that they exhibit a multifractal dependence on k and a rather unusual dependence on the temperature and on the periodicity L, which are supported by atypical realizations of the periodic disorder. We finally show that the distribution of A has a log-normal left tail and exhibits an essential singularity close to the right edge of the support, which is related to the Lifshitz singularity. Our findings are based both on analytic results and on extensive numerical simulations of the process x(t).

  12. The open quantum Brownian motions

    NASA Astrophysics Data System (ADS)

    Bauer, Michel; Bernard, Denis; Tilloy, Antoine

    2014-09-01

    Using quantum parallelism on random walks as the original seed, we introduce new quantum stochastic processes, the open quantum Brownian motions. They describe the behaviors of quantum walkers—with internal degrees of freedom which serve as random gyroscopes—interacting with a series of probes which serve as quantum coins. These processes may also be viewed as the scaling limit of open quantum random walks and we develop this approach along three different lines: the quantum trajectory, the quantum dynamical map and the quantum stochastic differential equation. We also present a study of the simplest case, with a two level system as an internal gyroscope, illustrating the interplay between the ballistic and diffusive behaviors at work in these processes. Notation H_z : orbital (walker) Hilbert space, {C}^{{Z}} in the discrete, L^2({R}) in the continuum H_c : internal spin (or gyroscope) Hilbert space H_sys=H_z\\otimesH_c : system Hilbert space H_p : probe (or quantum coin) Hilbert space, H_p={C}^2 \\rho^tot_t : density matrix for the total system (walker + internal spin + quantum coins) \\bar \\rho_t : reduced density matrix on H_sys : \\bar\\rho_t=\\int dxdy\\, \\bar\\rho_t(x,y)\\otimes | x \\rangle _z\\langle y | \\hat \\rho_t : system density matrix in a quantum trajectory: \\hat\\rho_t=\\int dxdy\\, \\hat\\rho_t(x,y)\\otimes | x \\rangle _z\\langle y | . If diagonal and localized in position: \\hat \\rho_t=\\rho_t\\otimes| X_t \\rangle _z\\langle X_t | ρt: internal density matrix in a simple quantum trajectory Xt: walker position in a simple quantum trajectory Bt: normalized Brownian motion ξt, \\xi_t^\\dagger : quantum noises

  13. Effect of Energy Drinks on Discoloration of Silorane and Dimethacrylate-Based Composite Resins

    PubMed Central

    Ahmadizenouz, Ghazaleh; Esmaeili, Behnaz; Ahangari, Zohreh; Khafri, Soraya; Rahmani, Aghil

    2016-01-01

    Objectives: This study aimed to assess the effects of two energy drinks on color change (ΔE) of two methacrylate-based and a silorane-based composite resin after one week and one month. Materials and Methods: Thirty cubic samples were fabricated from Filtek P90, Filtek Z250 and Filtek Z350XT composite resins. All the specimens were stored in distilled water at 37°C for 24 hours. Baseline color values (L*a*b*) of each specimen were measured using a spectrophotometer according to the CIEL*a*b* color system. Ten randomly selected specimens from each composite were then immersed in the two energy drinks (Hype, Red Bull) and artificial saliva (control) for one week and one month. Color was re-assessed after each storage period and ΔE values were calculated. The data were analyzed using the Kruskal Wallis and Mann–Whitney U tests. Results: Filtek Z250 composite showed the highest ΔE irrespective of the solutions at both time points. After seven days and one month, the lowest ΔE values were observed in Filtek Z350XT and Filtek P90 composites immersed in artificial saliva, respectively. The ΔE values of Filtek Z250 and Z350XT composites induced by Red Bull and Hype energy drinks were not significantly different. Discoloration of Filtek P90 was higher in Red Bull energy drink at both time points. Conclusions: Prolonged immersion time in all three solutions increased ΔE values of all composites. However, the ΔE values were within the clinically acceptable range (<3.3) at both time points. PMID:28127318

  14. The influence of cyclic shear fatigue on the bracket-adhesive-enamel complex: an in vitro study.

    PubMed

    Daratsianos, Nikolaos; Musabegovic, Ena; Reimann, Susanne; Grüner, Manfred; Jäger, Andreas; Bourauel, Christoph

    2013-05-01

    To describe the effect of fatigue on the strength of the bracket-adhesive-enamel complex and characterize the fatigue behavior of the materials tested. Upper central incisor brackets (Discovery(®), Dentaurum) were bonded with a light-curing (Transbond XT™, 3M Unitek) and a chemically-curing adhesive (Concise™, 3M Unitek) on bovine teeth embedded in cylindrical resign bases and stored in water at 37(±2)°C for 24 (±2)h. The first 15 specimens were tested with a universal testing machine ZMART.PRO(®) (Zwick GmbH & Co. KG, Ulm, Germany) for ultimate shear bond strength according to the DIN-13990-2-standard. The remaining three groups of 20 specimens underwent fatigue staircase testing of 100, 1000 and 3000 cycles at 1Hz with a self-made testing machine. The survived specimens were subjected to shear strength testing. The fatigued specimens showed decreased shear strength with both adhesives at all cycle levels. The shear strength after fatigue for 100, 1000 and 3000 cycles was in the Concise™-groups 34.8%, 59.0%, 47.3% and in the Transbond™ XT-groups 33.6%, 23.1%, 27.3% relative to the ultimate shear strength. The fatigue life of the Concise™-groups decreased with increasing stress and Transbond™ XT showed lower fatigue ratio with no obvious trend. The specimens bonded with Transbond™ XT showed typically favorable fracture modes in contrary to Concise™. Fatigue of the bracket-adhesive-enamel complex decreased its shear strength. The staircase method can provide a standardized experimental protocol for fatigue studies, however testing at various cycle numbers is recommended. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  15. Effect of thermal aging on the tensile bond strength at reduced areas of seven current adhesives.

    PubMed

    Baracco, Bruno; Fuentes, M Victoria; Garrido, Miguel A; González-López, Santiago; Ceballos, Laura

    2013-07-01

    The purpose of this study was to determine the micro-tensile bond strength (MTBS) to dentin of seven adhesive systems (total and self-etch adhesives) after 24 h and 5,000 thermocycles. Dentin surfaces of human third molars were exposed and bonded with two total-etch adhesives (Adper Scotchbond 1 XT and XP Bond), two two-step self-etch adhesives (Adper Scotchbond SE and Filtek Silorane Adhesive System) and three one-step self-etch adhesives (G-Bond, Xeno V and Bond Force). All adhesive systems were applied following manufacturers' instructions. Composite buildups were constructed and the bonded teeth were then stored in water (24 h, 37 °C) or thermocycled (5,000 cycles) before being sectioned and submitted to MTBS test. Two-way ANOVA and subsequent comparison tests were applied at α = 0.05. Characteristic de-bonded specimens were analyzed using scanning electron microscopy (SEM). After 24 h water storage, MTBS values were highest with XP Bond, Adper Scotchbond 1 XT, Filtek Silorane Adhesive System and Adper Scotchbond SE and lowest with the one-step self-etch adhesives Bond Force, Xeno V and G-Bond. After thermocycling, MTBS values were highest with XP Bond, followed by Filtek Silorane Adhesive System, Adper Scotchbond SE and Adper Scotchbond 1 XT and lowest with the one-step self-etch adhesives Bond Force, Xeno V and G-Bond. Thermal aging induced a significant decrease in MTBS values with all adhesives tested. The resistance of resin-dentin bonds to thermal-aging degradation was material dependent. One-step self-etch adhesives obtained the lowest MTBS results after both aging treatments, and their adhesive capacity was significantly reduced after thermocycling.

  16. Estimating the frequency interval of a regularly spaced multicomponent harmonic line signal in colored noise

    NASA Astrophysics Data System (ADS)

    Frazer, Gordon J.; Anderson, Stuart J.

    1997-10-01

    The radar returns from some classes of time-varying point targets can be represented by the discrete-time signal plus noise model: xt equals st plus [vt plus (eta) t] equals (summation)i equals o P minus 1 Aiej2(pi f(i)/f(s)t) plus vt plus (eta) t, t (epsilon) 0, . . ., N minus 1, fi equals kfI plus fo where the received signal xt corresponds to the radar return from the target of interest from one azimuth-range cell. The signal has an unknown number of components, P, unknown complex amplitudes Ai and frequencies fi. The frequency parameters fo and fI are unknown, although constrained such that fo less than fI/2 and parameter k (epsilon) {minus u, . . ., minus 2, minus 1, 0, 1, 2, . . ., v} is constrained such that the component frequencies fi are bound by (minus fs/2, fs/2). The noise term vt, is typically colored, and represents clutter, interference and various noise sources. It is unknown, except that (summation)tvt2 less than infinity; in general, vt is not well modelled as an auto-regressive process of known order. The additional noise term (eta) t represents time-invariant point targets in the same azimuth-range cell. An important characteristic of the target is the unknown parameter, fI, representing the frequency interval between harmonic lines. It is desired to determine an estimate of fI from N samples of xt. We propose an algorithm to estimate fI based on Thomson's harmonic line F-Test, which is part of the multi-window spectrum estimation method and demonstrate the proposed estimator applied to target echo time series collected using an experimental HF skywave radar.

  17. On the role of adhesion in single-file dynamics

    NASA Astrophysics Data System (ADS)

    Fouad, Ahmed M.; Noel, John A.

    2017-08-01

    For a one-dimensional interacting system of Brownian particles with hard-core interactions (a single-file model), we study the effect of adhesion on both the collective diffusion (diffusion of the entire system with respect to its center of mass) and the tracer diffusion (diffusion of the individual tagged particles). For the case with no adhesion, all properties of these particle systems that are independent of particle labeling (symmetric in all particle coordinates and velocities) are identical to those of non-interacting particles (Lebowitz and Percus, 1967). We clarify this last fact twice. First, we derive our analytical predictions that show that the probability-density functions of single-file (ρsf) and ordinary (ρord) diffusion are identical, ρsf =ρord, predicting a nonanomalous (ordinary) behavior for the collective single-file diffusion, where the average second moment with respect to the center of mass, < x(t) 2 > , is calculated from ρ for both diffusion processes. Second, for single-file diffusion, we show, both analytically and through large-scale simulations, that < x(t) 2 > grows linearly with time, confirming the nonanomalous behavior. This nonanomalous collective behavior comes in contrast to the well-known anomalous sub-diffusion behavior of the individual tagged particles (Harris, 1965). We introduce adhesion to single-file dynamics as a second inter-particle interaction rule and, interestingly, we show that adding adhesion does reduce the magnitudes of both < x(t) 2 > and the mean square displacement per particle Δx2; but the diffusion behavior remains intact independent of adhesion in both cases. Moreover, we study the dependence of both the collective diffusion constant D and the tracer diffusion constant DT on the adhesion coefficient α.

  18. Effects of SofZia-preserved travoprost and benzalkonium chloride-preserved latanoprost on the ocular surface -- a multicentre randomized single-masked study.

    PubMed

    Aihara, Makoto; Oshima, Hiromi; Araie, Makoto

    2013-02-01

    To assess the effect of SofZia-preserved travoprost on ocular surface conditions in comparison with benzalkonium chloride (BAK)-preserved latanoprost. A prospective randomized multicentre single-masked comparative study. Patients with open-angle glaucoma or ocular hypertension who had been treated with BAK-preserved latanoprost 0.005% (Xalatan(®) ) monotherapy for at least 3 months. Patients were enrolled at 23 facilities. Patients were randomly divided into the X-X group, continuous use of Xalatan(®) , or the X-T group, switching from Xalatan(®) to SofZia-preserved travoprost 0.004% (TravatanZ(®) ), and followed for 3 months. The superficial punctate keratopathy (SPK), conjunctival epitheliopathy, hyperaemia, tear break-up time (TBUT) and intraocular pressure (IOP) were examined for each patient in a masked manner. Changes in the frequency of keratoconjunctival epitheliopathy were evaluated 3 months after study initiation. Intra- and intergroup comparisons of changes in SPK, conjunctival epitheliopathy, hyperaemia, TBUT and IOP were also carried out. Two hundred twenty patients participated and 215 completed the 3-month study. The frequency of keratoconjunctival epitheliopathy significantly decreased in the X-T group (p = 0.036) and the intergroup difference was also significant (p = 0.001). SPK scores and TBUT were significantly improved in the X-T group (p = 0.034, 0.049), also with significant intergroup differences in the cornea excluding the inferior area and TBUT. There were no significant intergroup differences in changes of the hyperaemia scores and the IOP reduction. Switching to SofZia-preserved travoprost after BAK-preserved latanoprost resulted in a lower incidence of keratoconjunctival epitheliopathy, especially in the cornea, with no clinically relevant changes in hyperaemia and IOP. © 2012 The Authors. Acta Ophthalmologica © 2012 Acta Ophthalmologica Scandinavica Foundation.

  19. Rapid identification of drug-type strains in Cannabis sativa using loop-mediated isothermal amplification assay.

    PubMed

    Kitamura, Masashi; Aragane, Masako; Nakamura, Kou; Watanabe, Kazuhito; Sasaki, Yohei

    2017-01-01

    In Cannabis sativa L., tetrahydrocannabinol (THC) is the primary psychoactive compound and exists as the carboxylated form, tetrahydrocannabinolic acid (THCA). C. sativa is divided into two strains based on THCA content-THCA-rich (drug-type) strains and THCA-poor (fiber-type) strains. Both strains are prohibited by law in many countries including Japan, whereas the drug-type strains are regulated in Canada and some European countries. As the two strains cannot be discriminated by morphological analysis, a simple method for identifying the drug-type strains is required for quality control in legal cultivation and forensic investigation. We have developed a novel loop-mediated isothermal amplification (LAMP) assay for identifying the drug-type strains of C. sativa. We designed two selective LAMP primer sets for on-site or laboratory use, which target the drug-type THCA synthase gene. The LAMP assay was accomplished within approximately 40 min. The assay showed high specificity for the drug-type strains and its sensitivity was the same as or higher than that of conventional polymerase chain reaction. We also showed the effectiveness of melting curve analysis that was conducted after the LAMP assay. The melting temperature values of the drug-type strains corresponded to those of the cloned drug-type THCA synthase gene, and were clearly different from those of the cloned fiber-type THCA synthase gene. Moreover, the LAMP assay with simple sample preparation could be accomplished within 1 h from sample treatment to identification without the need for special devices or techniques. Our rapid, sensitive, specific, and simple assay is expected to be applicable to laboratory and on-site detection.

  20. 75 FR 14425 - Marine Mammals; File No. 14486

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-25

    ... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration RIN 0648-XT56 Marine Mammals; File No. 14486 AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric..., Responsible Party) has been issued a permit to receive, import, and export marine mammal parts for purposes of...

  1. 77 FR 2040 - Marine Mammals; File No. 14676

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-13

    ... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration RIN 0648-XT82 Marine Mammals; File No. 14676 AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric... Division, Office of Protected Resources, National Marine Fisheries Service. [FR Doc. 2012-502 Filed 1-12-12...

  2. 75 FR 1029 - Marine Mammals; File No. 14486

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-08

    ... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration RIN 0648-XT56 Marine Mammals; File No. 14486 AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric... Division, Office of Protected Resources, National Marine Fisheries Service. [FR Doc. 2010-139 Filed 1-7-10...

  3. Franklin: User Experiences

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    National Energy Research Supercomputing Center; He, Yun; Kramer, William T.C.

    2008-05-07

    The newest workhorse of the National Energy Research Scientific Computing Center is a Cray XT4 with 9,736 dual core nodes. This paper summarizes Franklin user experiences from friendly early user period to production period. Selected successful user stories along with top issues affecting user experiences are presented.

  4. Collective Framework and Performance Optimizations to Open MPI for Cray XT Platforms

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ladd, Joshua S; Gorentla Venkata, Manjunath; Shamis, Pavel

    2011-01-01

    The performance and scalability of collective operations plays a key role in the performance and scalability of many scientific applications. Within the Open MPI code base we have developed a general purpose hierarchical collective operations framework called Cheetah, and applied it at large scale on the Oak Ridge Leadership Computing Facility's Jaguar (OLCF) platform, obtaining better performance and scalability than the native MPI implementation. This paper discuss Cheetah's design and implementation, and optimizations to the framework for Cray XT 5 platforms. Our results show that the Cheetah's Broadcast and Barrier perform better than the native MPI implementation. For medium data,more » the Cheetah's Broadcast outperforms the native MPI implementation by 93% for 49,152 processes problem size. For small and large data, it out performs the native MPI implementation by 10% and 9%, respectively, at 24,576 processes problem size. The Cheetah's Barrier performs 10% better than the native MPI implementation for 12,288 processes problem size.« less

  5. Resource-Efficient, Hierarchical Auto-Tuning of a Hybrid Lattice Boltzmann Computation on the Cray XT4

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Computational Research Division, Lawrence Berkeley National Laboratory; NERSC, Lawrence Berkeley National Laboratory; Computer Science Department, University of California, Berkeley

    2009-05-04

    We apply auto-tuning to a hybrid MPI-pthreads lattice Boltzmann computation running on the Cray XT4 at National Energy Research Scientific Computing Center (NERSC). Previous work showed that multicore-specific auto-tuning can improve the performance of lattice Boltzmann magnetohydrodynamics (LBMHD) by a factor of 4x when running on dual- and quad-core Opteron dual-socket SMPs. We extend these studies to the distributed memory arena via a hybrid MPI/pthreads implementation. In addition to conventional auto-tuning at the local SMP node, we tune at the message-passing level to determine the optimal aspect ratio as well as the correct balance between MPI tasks and threads permore » MPI task. Our study presents a detailed performance analysis when moving along an isocurve of constant hardware usage: fixed total memory, total cores, and total nodes. Overall, our work points to approaches for improving intra- and inter-node efficiency on large-scale multicore systems for demanding scientific applications.« less

  6. Novel orthodontic cement containing dimethylaminohexadecyl methacrylate with strong antibacterial capability.

    PubMed

    Feng, Xiaodong; Zhang, Ning; Xu, Hockin H K; Weir, Michael D; Melo, Mary Anne S; Bai, Yuxing; Zhang, Ke

    2017-09-26

    Orthodontic treatments increase the incidence of white spot lesions. The objectives of this study were to develop an antibacterial orthodontic cement to inhibit demineralization, and to evaluate its enamel shear bond strength and anti-biofilm properties. Novel antibacterial monomer dimethylaminohexadecyl methacrylate (DMAHDM) was synthesized and incorporated into Transbond XT at 0, 1.5 and 3% by mass. Anti-biofilm activity was assessed using a human dental plaque microcosm biofilm model. Shear bond strength and adhesive remnant index were also tested. Biofilm activity precipitously dropped when contacting orthodontic cement with DMAHDM. Orthodontic cement containing 3% DMAHDM significantly reduced biofilm metabolic activity and lactic acid production (p<0.05), and decreased biofilm colony-forming unit (CFU) by two log. Water-aging for 90 days had no adverse influence on enamel shear bond strength (p>0.1). By incorporating DMAHDM into Transbond XT for the first time, the modified orthodontic cement obtained a strong antibacterial capability without compromising the enamel bond strength.

  7. The Equilibrium and Pre-equilibrium Triton Emission Spectra of Some Target Nuclei for ( n, xt) Reactions up to 45 MeV Energy

    NASA Astrophysics Data System (ADS)

    Tel, E.; Kaplan, A.; Aydın, A.; Özkorucuklu, S.; Büyükuslu, H.; Yıldırım, G.

    2010-08-01

    Although there have been significant research and development studies on the inertial and magnetic fusion reactor technology, there is still a long way to go to penetrate commercial fusion reactors to the energy market. Tritium self-sufficiency must be maintained for a commercial power plant. For self-sustaining (D-T) fusion driver tritium breeding ratio should be greater than 1.05. So, working out the systematics of ( n,t) reaction cross sections and triton emission differential data are important for the given reaction taking place on various nuclei at different energies. In this study, ( n,xt) reactions for some target nuclei as 16O, 27Al, 59Co and 209Bi have been investigated up to 45 MeV incident neutron energy. In the calculations of the triton emission spectra, the pre-equilibrium and equilibrium effects have been used. The calculated results have been compared with the experimental data taken from the literature.

  8. Diffusion in random networks

    DOE PAGES

    Zhang, Duan Z.; Padrino, Juan C.

    2017-06-01

    The ensemble averaging technique is applied to model mass transport by diffusion in random networks. The system consists of an ensemble of random networks, where each network is made of pockets connected by tortuous channels. Inside a channel, fluid transport is assumed to be governed by the one-dimensional diffusion equation. Mass balance leads to an integro-differential equation for the pocket mass density. The so-called dual-porosity model is found to be equivalent to the leading order approximation of the integration kernel when the diffusion time scale inside the channels is small compared to the macroscopic time scale. As a test problem,more » we consider the one-dimensional mass diffusion in a semi-infinite domain. Because of the required time to establish the linear concentration profile inside a channel, for early times the similarity variable is xt $-$1/4 rather than xt $-$1/2 as in the traditional theory. We found this early time similarity can be explained by random walk theory through the network.« less

  9. Parallel implementation of a Lagrangian-based model on an adaptive mesh in C++: Application to sea-ice

    NASA Astrophysics Data System (ADS)

    Samaké, Abdoulaye; Rampal, Pierre; Bouillon, Sylvain; Ólason, Einar

    2017-12-01

    We present a parallel implementation framework for a new dynamic/thermodynamic sea-ice model, called neXtSIM, based on the Elasto-Brittle rheology and using an adaptive mesh. The spatial discretisation of the model is done using the finite-element method. The temporal discretisation is semi-implicit and the advection is achieved using either a pure Lagrangian scheme or an Arbitrary Lagrangian Eulerian scheme (ALE). The parallel implementation presented here focuses on the distributed-memory approach using the message-passing library MPI. The efficiency and the scalability of the parallel algorithms are illustrated by the numerical experiments performed using up to 500 processor cores of a cluster computing system. The performance obtained by the proposed parallel implementation of the neXtSIM code is shown being sufficient to perform simulations for state-of-the-art sea ice forecasting and geophysical process studies over geographical domain of several millions squared kilometers like the Arctic region.

  10. Transcatheter aortic valve implantation transapical: step by step.

    PubMed

    Walther, Thomas; Möllmann, Helge; van Linden, Arnaud; Kempfert, Jörg

    2011-01-01

    Transcatheter aortic valve implantation (T-AVI) has been introduced into clinical practice to treat high-risk elderly patients with aortic stenosis. T-AVI can be performed by using a retrograde transfemoral (TF), transsubclavian, transaortic, and/or antegrade transapical (TA) approach. For TA-AVI, CE mark approval was granted in 2008 for the Edwards SAPIEN (Edwards Lifesciences, Irvine, CA) prosthesis with the Ascendra delivery system and in 2010 for the second-generation Edwards SAPIEN XT prosthesis and the Ascendra II delivery system, with 23-mm and 26-mm valves. In 2011, CE mark approval has been granted for TA-AVI by using the SAPIEN XT 29-mm prosthesis. Several other devices from different companies (Jenavalve, Jena Valve Inc, Munich, Germany; Embracer, Medtronic Inc, Guilford, CT; Accurate, Symetis Inc, Geneva, Switzerland) have passed "first in man trials" successfully and are being evaluated within multicenter pivotal studies. In this article we will focus on specific aspects of the TA technique for AVI. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Onboard data-processing architecture of the soft X-ray imager (SXI) on NeXT satellite

    NASA Astrophysics Data System (ADS)

    Ozaki, Masanobu; Dotani, Tadayasu; Tsunemi, Hiroshi; Hayashida, Kiyoshi; Tsuru, Takeshi G.

    2004-09-01

    NeXT is the X-ray satellite proposed for the next Japanese space science mission. While the satellite total mass and the launching vehicle are similar to the prior satellite Astro-E2, the sensitivity is much improved; it requires all the components to be lighter and faster than previous architecture. This paper shows the data processing architecture of the X-ray CCD camera system SXI (Soft X-ray Imager), which is the top half of the WXI (Wide-band X-ray Imager) of the sensitivity in 0.2-80keV. The system is basically a variation of Astro-E2 XIS, but event extraction speed is much faster than it to fulfill the requirements coming from the large effective area and fast exposure period. At the same time, data transfer lines between components are redesigned in order to reduce the number and mass of the wire harnesses that limit the flexibility of the component distribution.

  12. Epidemiological typing of Enterobacter aerogenes.

    PubMed Central

    Gaston, M A; Strickland, M A; Ayling-Smith, B A; Pitt, T L

    1989-01-01

    The applicability of Enterobacter cloacae and Klebsiella typing reagents for classifying clinical strains of Enterobacter aerogenes was evaluated. Of 75 strains, none were agglutinated by E. cloacae O antisera or were sensitive to E. cloacae bacteriophages. In contrast, 70 strains reacted with Klebsiella capsular antisera. Two-thirds of the strains were lysed by Klebsiella typing phages. A set of five E. aerogenes bacteriocin producers classified 92% of strains into 15 sensitivity types. In conclusion, E. aerogenes may be typed with Klebsiella reagents, and the simple bacteriocin test provides further discrimination between strains. The limited number of capsular antigens in the species and their apparent similarity to Klebsiella capsular antigens warrant further investigation. PMID:2715326

  13. Revision of the taxonomic status of type strains of Mesorhizobium loti and reclassification of strain USDA 3471T as the type strain of Mesorhizobiumerdmanii sp. nov. and ATCC 33669T as the type strain of Mesorhizobiumjarvisii sp. nov.

    PubMed

    Martínez-Hidalgo, Pilar; Ramírez-Bahena, Martha Helena; Flores-Félix, José David; Rivas, Raúl; Igual, José M; Mateos, Pedro F; Martínez-Molina, Eustoquio; León-Barrios, Milagros; Peix, Álvaro; Velázquez, Encarna

    2015-06-01

    The species Mesorhizobim loti was isolated from nodules of Lotus corniculatus and its type strain deposited in several collections. Some of these type strains, such as those deposited in the USDA and ATCC collections before 1990, are not coincident with the original strain, NZP 2213T, deposited in the NZP culture collection. The analysis of the 16S rRNA gene showed that strains USDA 3471T and ATCC 33669T formed independent branches from that occupied by Mesorhizobium loti NZP 2213T and related to those occupied by Mesorhizobium opportunistum WSM2075T and Mesorhizobium huakuii IFO 15243T, respectively, with 99.9 % similarity in both cases. However, the analysis of concatenated recA, atpD and glnII genes with similarities lower than 96, 98 and 94 %, respectively, between strains USDA 3471T and M. opportunistum WSM2075T and between strains ATCC 33669T and M. huakuii IFO 15243T, indicated that the strains USDA 3471T and ATCC 33669T represent different species of the genus Mesorhizobium. These results were confirmed by DNA-DNA hybridization experiments and phenotypic characterization. Therefore, the two strains were reclassified as representatives of the two species Mesorhizobium erdmanii sp. nov. (type strain USDA 3471T = CECT 8631T = LMG 17826t2T) and Mesorhizobium jarvisii sp. nov. (type strain ATCC 33669T = CECT 8632T = LMG 28313T).

  14. Discriminatory Indices of Typing Methods for Epidemiologic Analysis of Contemporary Staphylococcus aureus Strains.

    PubMed

    Rodriguez, Marcela; Hogan, Patrick G; Satola, Sarah W; Crispell, Emily; Wylie, Todd; Gao, Hongyu; Sodergren, Erica; Weinstock, George M; Burnham, Carey-Ann D; Fritz, Stephanie A

    2015-09-01

    Historically, a number of typing methods have been evaluated for Staphylococcus aureus strain characterization. The emergence of contemporary strains of community-associated S. aureus, and the ensuing epidemic with a predominant strain type (USA300), necessitates re-evaluation of the discriminatory power of these typing methods for discerning molecular epidemiology and transmission dynamics, essential to investigations of hospital and community outbreaks. We compared the discriminatory index of 5 typing methods for contemporary S. aureus strain characterization. Children presenting to St. Louis Children's Hospital and community pediatric practices in St. Louis, Missouri (MO), with community-associated S. aureus infections were enrolled. Repetitive sequence-based PCR (repPCR), pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), staphylococcal protein A (spa), and staphylococcal cassette chromosome (SCC) mec typing were performed on 200 S. aureus isolates. The discriminatory index of each method was calculated using the standard formula for this metric, where a value of 1 is highly discriminatory and a value of 0 is not discriminatory. Overall, we identified 26 distinct strain types by repPCR, 17 strain types by PFGE, 30 strain types by MLST, 68 strain types by spa typing, and 5 strain types by SCCmec typing. RepPCR had the highest discriminatory index (D) of all methods (D = 0.88), followed by spa typing (D = 0.87), MLST (D = 0.84), PFGE (D = 0.76), and SCCmec typing (D = 0.60). The method with the highest D among MRSA isolates was repPCR (D = 0.64) followed by spa typing (D = 0.45) and MLST (D = 0.44). The method with the highest D among MSSA isolates was spa typing (D = 0.98), followed by MLST (D = 0.93), repPCR (D = 0.92), and PFGE (D = 0.89). Among isolates designated USA300 by PFGE, repPCR was most discriminatory, with 10 distinct strain types identified (D = 0.63). We identified 45 MRSA isolates which were classified as identical by PFGE, MLST, spa typing, and SCCmec typing (USA300, ST8, t008, SCCmec IV, respectively); within this collection, there were 5 distinct strain types identified by repPCR. The typing methods yielded comparable discriminatory power for S. aureus characterization overall; when discriminating among USA300 isolates, repPCR retained the highest discriminatory power. This property is advantageous for investigations conducted in the era of contemporary S. aureus infections.

  15. Discriminatory Indices of Typing Methods for Epidemiologic Analysis of Contemporary Staphylococcus aureus Strains

    PubMed Central

    Rodriguez, Marcela; Hogan, Patrick G.; Satola, Sarah W.; Crispell, Emily; Wylie, Todd; Gao, Hongyu; Sodergren, Erica; Weinstock, George M.; Burnham, Carey-Ann D.; Fritz, Stephanie A.

    2015-01-01

    Abstract Historically, a number of typing methods have been evaluated for Staphylococcus aureus strain characterization. The emergence of contemporary strains of community-associated S. aureus, and the ensuing epidemic with a predominant strain type (USA300), necessitates re-evaluation of the discriminatory power of these typing methods for discerning molecular epidemiology and transmission dynamics, essential to investigations of hospital and community outbreaks. We compared the discriminatory index of 5 typing methods for contemporary S. aureus strain characterization. Children presenting to St. Louis Children's Hospital and community pediatric practices in St. Louis, Missouri (MO), with community-associated S. aureus infections were enrolled. Repetitive sequence-based PCR (repPCR), pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), staphylococcal protein A (spa), and staphylococcal cassette chromosome (SCC) mec typing were performed on 200 S. aureus isolates. The discriminatory index of each method was calculated using the standard formula for this metric, where a value of 1 is highly discriminatory and a value of 0 is not discriminatory. Overall, we identified 26 distinct strain types by repPCR, 17 strain types by PFGE, 30 strain types by MLST, 68 strain types by spa typing, and 5 strain types by SCCmec typing. RepPCR had the highest discriminatory index (D) of all methods (D = 0.88), followed by spa typing (D = 0.87), MLST (D = 0.84), PFGE (D = 0.76), and SCCmec typing (D = 0.60). The method with the highest D among MRSA isolates was repPCR (D = 0.64) followed by spa typing (D = 0.45) and MLST (D = 0.44). The method with the highest D among MSSA isolates was spa typing (D = 0.98), followed by MLST (D = 0.93), repPCR (D = 0.92), and PFGE (D = 0.89). Among isolates designated USA300 by PFGE, repPCR was most discriminatory, with 10 distinct strain types identified (D = 0.63). We identified 45 MRSA isolates which were classified as identical by PFGE, MLST, spa typing, and SCCmec typing (USA300, ST8, t008, SCCmec IV, respectively); within this collection, there were 5 distinct strain types identified by repPCR. The typing methods yielded comparable discriminatory power for S. aureus characterization overall; when discriminating among USA300 isolates, repPCR retained the highest discriminatory power. This property is advantageous for investigations conducted in the era of contemporary S. aureus infections. PMID:26376402

  16. Characteristics of Extrinsic Fabry-Perot Interferometric (EFPI) Fiber-Optic Strain Gages

    NASA Technical Reports Server (NTRS)

    Hare, David A.; Moore, Thomas C., Sr.

    2000-01-01

    The focus of this paper is a comparison of the strain-measuring characteristics of one type of commercially available fiber-optic strain sensor with the performance of conventional resistance strain gages. Fabry-Perot type fiber-optic strain sensors were selected for this testing program. Comparative testing is emphasized and includes load testing at room temperature with apparent strain characterization cryogenically and at elevated temperatures. The absolute accuracy of either of these types of strain gages is not addressed.

  17. Specificity of monoclonal antibodies to strains of Dickeya sp. that cause bacterial heart rot of pineapple.

    PubMed

    Peckham, Gabriel D; Kaneshiro, Wendy S; Luu, Van; Berestecky, John M; Alvarez, Anne M

    2010-10-01

    During a severe outbreak of bacterial heart rot that occurred in pineapple plantations on Oahu, Hawaii, in 2003 and years following, 43 bacterial strains were isolated from diseased plants or irrigation water and identified as Erwinia chrysanthemi (now Dickeya sp.) by phenotypic, molecular, and pathogenicity assays. Rep-PCR fingerprint patterns grouped strains from pineapple plants and irrigation water into five genotypes (A-E) that differed from representatives of other Dickeya species, Pectobacterium carotovorum and other enteric saprophytes isolated from pineapple. Monoclonal antibodies produced following immunization of mice with virulent type C Dickeya sp. showed only two specificities. MAb Pine-1 (2D11G1, IgG1 with kappa light chain) reacted to all 43 pineapple/water strains and some reference strains (D. dianthicola, D. chrysanthemi, D. paradisiaca, some D. dadantii, and uncharacterized Dickeya sp.) but did not react to reference strains of D. dieffenbachiae, D. zeae, or one of the two Malaysian pineapple strains. MAb Pine-2 (2A7F2, IgG3 with kappa light chain) reacted to all type B, C, and D strains but not to any A or E strains or any reference strains except Dickeya sp. isolated from Malaysian pineapple. Pathogenicity tests showed that type C strains were more aggressive than type A strains when inoculated during cool months. Therefore, MAb Pine-2 distinguishes the more virulent type C strains from less virulent type A pineapple strains and type E water strains. MAbs with these two specificities enable development of rapid diagnostic tests that will distinguish the systemic heart rot pathogen from opportunistic bacteria associated with rotted tissues. Use of the two MAbs in field assays also permits the monitoring of a known subpopulation and provides additional decision tools for disease containment and management practices.

  18. Comparative c-type cytochrome expression analysis in Shewanella oneidensis strain MR-1 and Anaeromyxobacter dehalogenans strain 2CP-C grown with soluble and insoluble oxidised metal electron acceptors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nissen, Silke; Liu, Xiaoxin; Chourey, Karuna

    2012-01-01

    The genomes of Shewanella oneidensis strain MR-1 and Anaeromyxobacter dehalogenans strain 2CP-C encode 40 and 69 putative c-type cytochrome genes, respectively. Deletion mutant and biochemical studies have assigned specific functions to a few c-type cytochromes involved in electron transfer to oxidised metals in Shewanella oneidensis strain MR-1. Although promising, the genetic approach is limited to gene deletions that produce a distinct phenotype, and organism for which a genetic system is available. To more comprehensively investigate and compare c-type cytochrome expression in Shewanella oneidensis strain MR-1 and Anaeromyxobacter dehalogenans strain 2CP-C, proteomic measurements were used to characterise lysates of cells grownmore » with soluble Fe(III) (as ferric citrate) and insoluble Mn(IV) (as MnO2) as electron acceptors. Strain MR-1 expressed 19 and 20, and strain 2CP-C expressed 27 and 25 c-type cytochromes when grown with Fe(III) and Mn(IV), respectively. The majority of c-type cytochromes (77% for strain MR-1 and 63% for strain 2CP-C) were expressed under both growth conditions; however, the analysis also revealed unique c-type cytochromes that were specifically expressed in cells grown with soluble Fe(III) or insoluble Mn(IV). Proteomic characterisation proved to be a promising approach for determining the c-type cytochrome complement expressed under different growth conditions, and will help elucidating the specific functions of more c-type cytochromes that are the basis for Shewanella and Anaeromyxobacter respiratory versatility.« less

  19. An automated method to assay locomotor activity in third instar Drosophila melanogaster larvae.

    PubMed

    Graham, Stephanie; Rogers, Ryan P; Alper, Richard H

    2016-01-01

    The purpose of these studies was to describe a novel application of an automated data acquisition/data reduction system, DanioVision™ by Noldus. DanioVision™ has the ability to detect changes in locomotor activity in third instar Drosophila melanogaster larvae. The noncompetitive GABAA receptor antagonist picrotoxin (PTX), was used as a pharmacologic agent to decrease locomotor activity. Two strains of Drosophila were used in these studies; wild-type flies and flies with a mutation in the Rdl gene (Rdl(MD-RR)). Rdl(MD-RR)Drosophila are naturally occurring mutants that express an aberrant form of the GABAA receptor, which has a lower affinity for PTX, but not GABA itself. Larvae, extracted from food in 20% sucrose, were randomly placed into vials containing vehicle or PTX (0.03-3mM). After incubation of 2-24h, individual larvae were put in each well of a 6-well culture plate previously coated with 2% agar, the plate was then placed in the DanioVision™ apparatus. The activity of individual larva was recorded for 5 min, digitized and analyzed using Ethovision® XT software. Incubation of third instar wild-type larvae in 1mM PTX for 4 or 24h decreased activity; whereas, a 2h incubation in PTX was without effect. PTX caused a concentration-dependent decrease in activity as demonstrated by consistently reduced locomotor activity with 1.0 and 3.0mM: 0.3mM resulted in variable decreases in locomotor activity and 0.03 mM yielded no effect. By contrast, PTX did not affect activity in Rdl(MD-RR) larvae even at the highest concentration, 3.0mM. Using an automated data acquisition system, it was found that PTX decreases activity in third instar Drosophila larvae due to a selective blockade of the GABAA receptor. The method will reduce the likelihood of human error and bias, as well as increase the speed and ease of data collection and analysis. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Wild type measles virus attenuation independent of type I IFN.

    PubMed

    Druelle, Johan; Sellin, Caroline I; Waku-Kouomou, Diane; Horvat, Branka; Wild, Fabian T

    2008-02-03

    Measles virus attenuation has been historically performed by adaptation to cell culture. The current dogma is that attenuated virus strains induce more type I IFN and are more resistant to IFN-induced protection than wild type (wt). The adaptation of a measles virus isolate (G954-PBL) by 13 passages in Vero cells induced a strong attenuation of this strain in vivo. The adapted virus (G954-V13) differs from its parental strain by only 5 amino acids (4 in P/V/C and 1 in the M gene). While a vaccine strain, Edmonston Zagreb, could replicate equally well in various primate cells, both G954 strains exhibited restriction to the specific cell type used initially for their propagation. Surprisingly, we observed that both G954 strains induced type I IFN, the wt strain inducing even more than the attenuated ones, particularly in human plasmacytoid Dendritic Cells. Type I IFN-induced protection from the infection of both G954 strains depended on the cell type analyzed, being less efficient in the cells used to grow the viral strain. Thus, mutations in M and P/V/C proteins can critically affect MV pathogenicity, cellular tropism and lead to virus attenuation without interfering with the alpha/beta IFN system.

  1. Wild type measles virus attenuation independent of type I IFN

    PubMed Central

    Druelle, Johan; Sellin, Caroline I; Waku-Kouomou, Diane; Horvat, Branka; Wild, Fabian T

    2008-01-01

    Background Measles virus attenuation has been historically performed by adaptation to cell culture. The current dogma is that attenuated virus strains induce more type I IFN and are more resistant to IFN-induced protection than wild type (wt). Results The adaptation of a measles virus isolate (G954-PBL) by 13 passages in Vero cells induced a strong attenuation of this strain in vivo. The adapted virus (G954-V13) differs from its parental strain by only 5 amino acids (4 in P/V/C and 1 in the M gene). While a vaccine strain, Edmonston Zagreb, could replicate equally well in various primate cells, both G954 strains exhibited restriction to the specific cell type used initially for their propagation. Surprisingly, we observed that both G954 strains induced type I IFN, the wt strain inducing even more than the attenuated ones, particularly in human plasmacytoid Dendritic Cells. Type I IFN-induced protection from the infection of both G954 strains depended on the cell type analyzed, being less efficient in the cells used to grow the viral strain. Conclusion Thus, mutations in M and P/V/C proteins can critically affect MV pathogenicity, cellular tropism and lead to virus attenuation without interfering with the α/β IFN system. PMID:18241351

  2. Effect of condensed tannin profile on wheat flour dough rheology

    USDA-ARS?s Scientific Manuscript database

    Proanthocyanidins (PA) crosslink proteins and could expand wheat gluten functionality. Effect PA MW profile (sorghum versus grape seed PA) on rheology of flours with different gluten composition (high versus low insoluble polymeric protein, IPP) was evaluated using mixograph, large (TA.XT2i) and sm...

  3. Diphtheria in the Republic of Georgia: Use of Molecular Typing Techniques for Characterization of Corynebacterium diphtheriae Strains

    PubMed Central

    Sulakvelidze, Alexander; Kekelidze, Merab; Gomelauri, Tsaro; Deng, Yingkang; Khetsuriani, Nino; Kobaidze, Ketino; De Zoysa, Aruni; Efstratiou, Androulla; Morris, J. Glenn; Imnadze, Paata

    1999-01-01

    Sixty-six Corynebacterium diphtheriae strains (62 of the gravis biotype and 4 of the mitis biotype) isolated during the Georgian diphtheria epidemic of 1993 to 1998 and 13 non-Georgian C. diphtheriae strains (10 Russian and 3 reference isolates) were characterized by (i) biotyping, (ii) toxigenicity testing with the Elek assay and PCR, (iii) the randomly amplified polymorphic DNA (RAPD) technique, and (iv) pulsed-field gel electrophoresis (PFGE). Fifteen selected strains were ribotyped. Six RAPD types and 15 PFGE patterns were identified among all strains examined, and 12 ribotypes were found among the 15 strains that were ribotyped. The Georgian epidemic apparently was caused by one major clonal group of C. diphtheriae (PFGE type A, ribotype R1), which was identical to the predominant epidemic strain(s) isolated during the concurrent diphtheria epidemic in Russia. A dendrogram based on the PFGE patterns revealed profound differences between the minor (nonpredominant) epidemic strains found in Georgia and Russia. The methodologies for RAPD typing, ribotyping, and PFGE typing of C. diphtheriae strains were improved to enable rapid and convenient molecular typing of the strains. The RAPD technique was adequate for biotype differentiation; however, PFGE and ribotyping were better (and equal to each other) at discriminating between epidemiologically related and unrelated isolates. PMID:10488190

  4. Serological Typing of 31 Achromogenic and 40 Melanogenic Pseudomonas aeruginosa Strains

    PubMed Central

    Yabuuchi, Eiko; Miyajima, Noriko; Hotta, Hisako; Furu, Youichi

    1971-01-01

    Thirty-one achromogenic and 40 melanogenic Pseudomonas aeruginosa strains were studied with 10 monovalent typing sera (3). Twenty-one of the achromogenic (67.7%) and seven of the melanogenic (17.5%) strains were agglutinated by one of the 10 typing sera. Ten achromogenic and 33 melanogenic strains were not agglutinated by any of the 10 typing sera. As far as this set of antisera is concerned, the typability of achromogenic and melanogenic P. aeruginosa strains appears to be much lower than that of the chromogenic, nonmelanogenic strains of the species reported previously. PMID:5002137

  5. Surface antigens from Escherichia coli O2 and O78 strains of avian origin.

    PubMed Central

    Dho-Moulin, M; van den Bosch, J F; Girardeau, J P; Brée, A; Barat, T; Lafont, J P

    1990-01-01

    Fimbriae from O2 and O78 virulent strains of avian Escherichia coli were compared with type 1A fimbriae with regard to the apparent molecular weights of their subunits and their antigenic relationships. Under static broth culture conditions, most O78 strains expressed fimbriae closely related to those of type 1A. Under the same culture conditions, another type of fimbriae, sharing some common properties with type 1A fimbriae, was observed only on O2 strains; however, these fimbriae differed from type 1A fimbriae in the apparent molecular weights of their subunits and in the expression of specific epitopes. They were called type 1-like fimbriae. Homologies in lipopolysaccharide and outer membrane protein profiles were also demonstrated among the strains expressing type 1-like fimbriae, which suggests the existence of a clonal relationship among O2:K1 avian E. coli strains. The O78 strains studied did not appear to be clonally related. Images PMID:1968434

  6. [Multilocus sequence-typing for characterization of Moscow strains of Haemophilus influenzae type b].

    PubMed

    Platonov, A E; Mironov, K O; Iatsyshina, S B; Koroleva, I S; Platonova, O V; Gushchin, A E; Shipulin, G A

    2003-01-01

    Haemophilius influenzae, type b (Hib) bacteria, were genotyped by multilocus sequence typing (MLST) using 5 loci (adk, fucK, mdh, pgi, recA). 42 Moscow Hib strains (including 38 isolates form cerebrospinal fluid of children, who had purulent meningitis in 1999-2001, and 4 strains isolated from healthy carriers of Hib), as well as 2 strains from Yekaterinburg were studied. In MLST a strain is characterized, by alleles and their combinations (an allele profile) referred to also as sequence-type (ST). 9 Sts were identified within the Russian Hib bacteria: ST-1 was found in 25 strains (57%), ST-12 was found in 8 strains (18%), ST-11 was found in 4 strains (9%) and ST-15 was found in 2 strains (4.5%); all other STs strains (13, 14, 16, 17, 51) were found in isolated cases (2.3%). A comparison of allelic profiles and of nucleotide sequences showed that 93% of Russian isolates, i.e. strain with ST-1, 11, 12, 13, 15 and 17, belong to one and the same clonal complex. 2 isolates from Norway and Sweden from among 7 foreign Hib strains studied up to now can be described as belonging to the same clonal complex; 5 Hib strains were different from the Russian ones.

  7. Diagnostic tools based on minor groove binder probe technology for rapid identification of vaccinal and field strains of canine parvovirus type 2b.

    PubMed

    Decaro, Nicola; Martella, Vito; Elia, Gabriella; Desario, Costantina; Campolo, Marco; Buonavoglia, Domenico; Bellacicco, Anna Lucia; Tempesta, Maria; Buonavoglia, Canio

    2006-12-01

    TaqMan-based diagnostic tests have been developed for the identification of canine parvovirus type 2 (CPV-2) strains in the faeces of dogs with diarrhoea, including a minor groove binder (MGB) probe assay for identification of type 2-based vaccines and field strains (types 2a, 2b and 2c). Since type 2b vaccines have been licensed recently in Europe, two novel MGB assays were developed for discrimination between type 2b vaccines and field strains of CPV. Such assays have been found to be highly sensitive, specific and reproducible, allowing for simultaneous detection of type 2b vaccinal and field strains present in the same specimens. These new assays will help resolution of the diagnostic problems related to the detection of a type 2b strain in the faeces of dogs shortly after the administration of a type 2b vaccine.

  8. Comparison of Ribotyping, Randomly Amplified Polymorphic DNA Analysis, and Pulsed-Field Gel Electrophoresis in Typing of Lactobacillus rhamnosus and L. casei Strains

    PubMed Central

    Tynkkynen, Soile; Satokari, Reetta; Saarela, Maria; Mattila-Sandholm, Tiina; Saxelin, Maija

    1999-01-01

    A total of 24 strains, biochemically identified as members of the Lactobacillus casei group, were identified by PCR with species-specific primers. The same set of strains was typed by randomly amplified polymorphic DNA (RAPD) analysis, ribotyping, and pulsed-field gel electrophoresis (PFGE) in order to compare the discriminatory power of the methods. Species-specific primers for L. rhamnosus and L. casei identified the type strain L. rhamnosus ATCC 7469 and the neotype strain L. casei ATCC 334, respectively, but did not give any signal with the recently revived species L. zeae, which contains the type strain ATCC 15820 and the strain ATCC 393, which was previously classified as L. casei. Our results are in accordance with the suggested new classification of the L. casei group. Altogether, 21 of the 24 strains studied were identified with the species-specific primers. In strain typing, PFGE was the most discriminatory method, revealing 17 genotypes for the 24 strains studied. Ribotyping and RAPD analysis yielded 15 and 12 genotypes, respectively. PMID:10473394

  9. Comparison of ribotyping, randomly amplified polymorphic DNA analysis, and pulsed-field gel electrophoresis in typing of Lactobacillus rhamnosus and L. casei strains.

    PubMed

    Tynkkynen, S; Satokari, R; Saarela, M; Mattila-Sandholm, T; Saxelin, M

    1999-09-01

    A total of 24 strains, biochemically identified as members of the Lactobacillus casei group, were identified by PCR with species-specific primers. The same set of strains was typed by randomly amplified polymorphic DNA (RAPD) analysis, ribotyping, and pulsed-field gel electrophoresis (PFGE) in order to compare the discriminatory power of the methods. Species-specific primers for L. rhamnosus and L. casei identified the type strain L. rhamnosus ATCC 7469 and the neotype strain L. casei ATCC 334, respectively, but did not give any signal with the recently revived species L. zeae, which contains the type strain ATCC 15820 and the strain ATCC 393, which was previously classified as L. casei. Our results are in accordance with the suggested new classification of the L. casei group. Altogether, 21 of the 24 strains studied were identified with the species-specific primers. In strain typing, PFGE was the most discriminatory method, revealing 17 genotypes for the 24 strains studied. Ribotyping and RAPD analysis yielded 15 and 12 genotypes, respectively.

  10. Biochemical Characterization of Prion Strains in Bank Voles

    PubMed Central

    Pirisinu, Laura; Marcon, Stefano; Di Bari, Michele Angelo; D’Agostino, Claudia; Agrimi, Umberto; Nonno, Romolo

    2013-01-01

    Prions exist as different strains exhibiting distinct disease phenotypes. Currently, the identification of prion strains is still based on biological strain typing in rodents. However, it has been shown that prion strains may be associated with distinct PrPSc biochemical types. Taking advantage of the availability of several prion strains adapted to a novel rodent model, the bank vole, we investigated if any prion strain was actually associated with distinctive PrPSc biochemical characteristics and if it was possible to univocally identify strains through PrPSc biochemical phenotypes. We selected six different vole-adapted strains (three human-derived and three animal-derived) and analyzed PrPSc from individual voles by epitope mapping of protease resistant core of PrPSc (PrPres) and by conformational stability and solubility assay. Overall, we discriminated five out of six prion strains, while two different scrapie strains showed identical PrPSc types. Our results suggest that the biochemical strain typing approach here proposed was highly discriminative, although by itself it did not allow us to identify all prion strains analyzed. PMID:25437201

  11. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mijnheer, J.

    Let (X(t): O{le}t{le}{infinity} be a stable subordinator with {alpha} {element_of}). For increasing sequences t{sub k} we give normalizing constants a{sub k} such that lim inf{sub k{le}{infinity}} a {sup {minus}1}{sub k} X(t{sub k}) is a.s. constant. We also derive a.s. upper bounds.

  12. Dietary supplementation of young broiler chickens with Capsicum and turmeric oleoresins increases resistance to necrotic enteritis

    USDA-ARS?s Scientific Manuscript database

    The Clostridium-related poultry disease, necrotic enteritis (NE), causes substantial economic losses on a global scale. In this study, a mixture of two plant-derived phytonutrients, Capsicum oleoresin and turmeric oleoresin (XT), was evaluated for its effects on local and systemic immune responses ...

  13. Dietary supplementation of young broiler chickens with capsicum and turmeric oleoresin increases resistance to necrotic enteris

    USDA-ARS?s Scientific Manuscript database

    The Clostridium-related poultry disease, necrotic enteritis (NE), causes substantial economic losses on a global scale. In this study, a mixture of two plant-derived phytonutrients, Capsicum oleoresin and turmeric oleoresin (XT), was evaluated for its effects on local and systemic immune responses ...

  14. Implementation of the Automated Numerical Model Performance Metrics System

    DTIC Science & Technology

    2011-09-26

    question. As of this writing, the DSRC IBM AIX machines DaVinci and Pascal, and the Cray XT Einstein all use the PBS batch queuing system for...3.3). 12 Appendix A – General Automation System This system provides general purpose tools and a general way to automatically run

  15. 76 FR 80402 - Certain Personal Data and Mobile Communications Devices and Related Software; Final Determination...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-23

    ... Communications Devices and Related Software; Final Determination Finding Violation of Section 337; Issuance of a... importation of infringing personal data and mobile communications devices and related software. The Commission... subsidiary NeXT Software, Inc., both of Cupertino, California (collectively, ``Apple''), alleging a violation...

  16. ORPC RivGen Acoustic Measurements

    DOE Data Explorer

    Brian Polagye

    2016-06-06

    Drifting hydrophone measurements obtained around the Ocean Renewable Power Company RivGen turbine near the village of Igiugig, Alaska in August, 2014. Each data set contains hydrophone voltage (as well as gain and sensitivity), position on the river (LAT, LONG, and proximity to turbine [xt, yt]), drift velocity, and contextual meteorological data.

  17. Draft Genome Sequences for Two Metal-Reducing Pelosinus fermentans Strains Isolated from a Cr(VI)-Contaminated Site and for Type Strain R7

    PubMed Central

    Brown, Steven D.; Podar, Mircea; Klingeman, Dawn M.; Johnson, Courtney M.; Yang, Zamin K.; Utturkar, Sagar M.; Land, Miriam L.; Mosher, Jennifer J.; Hurt, Richard A.; Phelps, Tommy J.; Palumbo, Anthony V.; Arkin, Adam P.; Hazen, Terry C.

    2012-01-01

    Pelosinus fermentans 16S rRNA gene sequences have been reported from diverse geographical sites since the recent isolation of the type strain. We present the genome sequence of the P. fermentans type strain R7 (DSM 17108) and genome sequences for two new strains with different abilities to reduce iron, chromate, and uranium. PMID:22933770

  18. Impact of Air Temperature and SST Variability on Cholera Incidence in Southeastern Africa, 1971-2006

    NASA Astrophysics Data System (ADS)

    Paz, Shlomit

    2010-05-01

    The most important climatic parameter related to cholera outbreaks is the temperature, especially of the water bodies and the aquatic environment. This factor governs the survival and growth of V. cholerae, since it has a direct influence on its abundance in the environment, or alternatively, through its indirect influence on other aquatic organisms to which the pathogen is found to attach. Thus, the potential for cholera outbreaks may rise, parallel to the increase in ocean surface temperature. Indeed, recent studies indicate that global warming might create a favorable environment for V. cholerae and increase its incidence in vulnerable areas. Africa is vulnerable to climate variability. According to the recent IPCC report on Africa, the air temperature has indicated a significant warming trend since the 1960s. In recent years, most of the research into disease vectors in Africa related to climate variability has focused on malaria. The IPCC indicated that the need exists to examine the vulnerabilities and impacts of climatic factors on cholera in Africa. In light of this, the study uses a Poisson Regression Model to analyze the possible association between the cholera rates in southeastern Africa and the annual variability of air temperature and sea surface temperature (SST) at regional and hemispheric scales, for the period 1971-2006. Data description is as follows: Number of cholera cases per year in Uganda, Kenya, Rwanda, Burundi, Tanzania, Malawi, Zambia and Mozambique. Source: WHO Global Health Atlas - cholera. Seasonal and annual temperature time series: Regional scale: a) Air temperature for southeastern Africa (30° E-36° E, 5° S-17° S), source: NOAA NCEP-NCAR; b) Sea surface temperature, for the western Indian Ocean (0-20° S, 40° E-45° E), source: NOAA, Kaplan SST dataset. Hemispheric scale (for the whole Southern Hemisphere): a) Air temperature anomaly; b) Sea surface temperature anomaly. Source: CRU, University of East Anglia. The following Poisson regression model is suggested: log{E(CHOLt)} = b0+b1×Xt+b2×Xt-1 where: CHOLt = the number of new cases of cholera in year t Xt / Xt-1 = the climate covariate measured in year t/t-1. (b0,b1) = the coefficients. A first order autocorrelation, AR1 = cor(Yt, Yt-1) is taken into account in the estimation using Generalized Estimating Equations. b1 and b2 quantify the association of CHOL and X, i.e. if Xt or Xt-1 increase by one unit, the mean of Yt is expected to increase in exp{b1} or exp{b2} times, respectively (multiplicative model). The results showed a significant exponential increase of cholera rates in humans during the study period, with an estimate of exp(b1)=1.08 (p-value = 0.02). Associations have been found between the annual increase of the air temperature in southeastern Africa and the cholera incidence in the same area. Linkages were found also for a wider scale, with the air temperature anomaly of the Southern Hemisphere, with an estimate of exp(b1)=1.18 (p-value = 0.04) and exp(b1)=1.26 (p-value = 0.006) for the previous year. Significant linkages were detected between the annual cholera rate and the annual western Indian Ocean' SST , with exp(b1) = 1.31 (p-value = 0.01) for the current year and exp(b1) = 1.23 (p-value = 0.05) for the previous year. Linkages were found also for the hemispheric scale, with the SST anomaly. The increase of global temperature may influence the temporal fluctuations of cholera, as well as potentially increasing the frequency and duration of its outbreaks. Despite future uncertainty, the climate variability has to be considered in predicting further cholera outbreaks in Africa. This may help to promote better, more efficient preparedness. For more details: Paz, S. 2010. Impact of Temperature Variability on Cholera Incidence in Southeastern Africa, 1971-2006. EcoHealth, in press.

  19. Fluid-flow measurements in low permeability media with high pressure gradients using neutron imaging: Application to concrete

    NASA Astrophysics Data System (ADS)

    Yehya, Mohamad; Andò, Edward; Dufour, Frédéric; Tengattini, Alessandro

    2018-05-01

    This article focuses on a new experimental apparatus for investigating fluid flow under high pressure gradients within low-permeability porous media by means of neutron imaging. A titanium Hassler cell which optimises neutron transparency while allowing high pressure confinement (up to 50 MPa) and injection is designed for this purpose and presented here. This contribution focuses on the development of the proposed methodology thanks to some preliminary results obtained using a new neutron imaging facility named NeXT on the D50 beamline at the Institute Laue Langevin (Grenoble). The preliminary test was conducted by injecting normal water into concrete sample prepared and saturated with heavy water to take advantage of the isotope sensitivity of neutrons. The front between these two types of water is tracked in space and time with a combination of neutron radiography and tomography.

  20. Computer-Aided Methodology for Syndromic Strabismus Diagnosis.

    PubMed

    Sousa de Almeida, João Dallyson; Silva, Aristófanes Corrêa; Teixeira, Jorge Antonio Meireles; Paiva, Anselmo Cardoso; Gattass, Marcelo

    2015-08-01

    Strabismus is a pathology that affects approximately 4 % of the population, causing aesthetic problems reversible at any age and irreversible sensory alterations that modify the vision mechanism. The Hirschberg test is one type of examination for detecting this pathology. Computer-aided detection/diagnosis is being used with relative success to aid health professionals. Nevertheless, the routine use of high-tech devices for aiding ophthalmological diagnosis and therapy is not a reality within the subspecialty of strabismus. Thus, this work presents a methodology to aid in diagnosis of syndromic strabismus through digital imaging. Two hundred images belonging to 40 patients previously diagnosed by an specialist were tested. The method was demonstrated to be 88 % accurate in esotropias identification (ET), 100 % for exotropias (XT), 80.33 % for hypertropias (HT), and 83.33 % for hypotropias (HoT). The overall average error was 5.6Δ and 3.83Δ for horizontal and vertical deviations, respectively, against the measures presented by the specialist.

  1. Microcomputer pollution model for civilian airports and Air Force bases. Model description

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Segal, H.M.; Hamilton, P.L.

    1988-08-01

    This is one of three reports describing the Emissions and Dispersion Modeling System (EDMS). EDMS is a complex source emissions/dispersion model for use at civilian airports and Air Force bases. It operates in both a refined and a screening mode and is programmed for an IBM-XT (or compatible) computer. This report--MODEL DESCRIPTION--provides the technical description of the model. It first identifies the key design features of both the emissions (EMISSMOD) and dispersion (GIMM) portions of EDMS. It then describes the type of meteorological information the dispersion model can accept and identifies the manner in which it preprocesses National Climatic Centermore » (NCC) data prior to a refined-model run. The report presents the results of running EDMS on a number of different microcomputers and compares EDMS results with those of comparable models. The appendices elaborate on the information noted above and list the source code.« less

  2. CRISPR/cas Loci of Type II Propionibacterium acnes Confer Immunity against Acquisition of Mobile Elements Present in Type I P. acnes

    PubMed Central

    Brüggemann, Holger; Lomholt, Hans B.; Tettelin, Hervé; Kilian, Mogens

    2012-01-01

    Propionibacterium acnes is a skin commensal that occasionally acts as an opportunistic pathogen. The population structure of this species shows three main lineages (I–III). While type I strains are mainly associated with sebaceous follicles of human skin and inflammatory acne, types II and III strains are more often associated with deep tissue infections. We investigated the occurrence and distribution of the clustered regularly interspaced short palindromic repeats (CRISPR) in P. acnes, assessed their immunological memory, and addressed the question if such a system could account for type-specific properties of the species. A collection of 108 clinical isolates covering all known phylotypes of P. acnes was screened for the existence of CRISPR/cas loci. We found that CRISPR loci are restricted to type II P. acnes strains. Sequence analyses of the CRISPR spacers revealed that the system confers immunity to P. acnes-specific phages and to two mobile genetic elements. These elements are found almost exclusively in type I P. acnes strains. Genome sequencing of a type I P. acnes isolate revealed that one element, 54 kb in size, encodes a putative secretion/tight adherence (TAD) system. Thus, CRISPR/cas loci in P. acnes recorded the exposure of type II strains to mobile genetic elements of type I strains. The CRISPR/cas locus is deleted in type I strains, which conceivably accounts for their ability to horizontally acquire fitness or virulence traits and might indicate that type I strains constitute a younger subpopulation of P. acnes. PMID:22479553

  3. High mortality among patients infected with hypervirulent antimicrobial-resistant capsular type K1 Klebsiella pneumoniae strains in Taiwan.

    PubMed

    Lin, Yi-Tsung; Cheng, Yi-Hsiang; Juan, Chih-Han; Wu, Ping-Feng; Huang, Yi-Wei; Chou, Sheng-Hua; Yang, Tsuey-Ching; Wang, Fu-Der

    2018-06-12

    Capsular type K1 Klebsiella pneumoniae, highly virulent strains which are common in Asian countries, can cause pyogenic infections. These hypervirulent strains are usually susceptible to most antimicrobials, except for ampicillin. Little is known regarding the clinical and molecular characteristics of antimicrobial-resistant K1 K. pneumoniae strains. This retrospective study evaluated patients infected with capsular type K1 K. pneumoniae strains in a Taiwanese medical centre between April 2013 and March 2016. Antimicrobial-resistant strains were defined based on non-susceptibility to antimicrobial agents except ampicillin. We compared the clinical outcome of patients infected with and without antimicrobial-resistant strains. The in vivo virulence, genetic relatedness, and resistance mechanisms of these hypervirulent antimicrobial-resistant strains were also investigated. A total of 182 capsular type K1 K. pneumoniae strains were identified, including 18 antimicrobial-resistant strains. The 28-day mortality rate among the 18 cases caused by antimicrobial-resistant strains was significantly higher than that among 164 cases caused by antimicrobial-sensitive strains (50% vs. 10.4%, p < 0.001). Infection with antimicrobial-resistant strain independently increased the 28-day mortality risk. Most antimicrobial -resistant strains were not clonally related, and they exhibited high in vivo virulence in a mouse lethality experiment. The major resistance mechanisms involved the presence of β-lactamases and the overexpression of efflux pumps. In conclusion, hypervirulent antimicrobial-resistant capsular type K1 K. pneumoniae strains can predispose to a fatal outcome. These strains may represent an emerging threat to public health in Taiwan. Copyright © 2018. Published by Elsevier B.V.

  4. Molecular epidemiology of methicillin-resistant Staphylococcus aureus isolated in serial cultures from the respiratory tract of children with cystic fibrosis.

    PubMed

    Al-Zubeidi, Duha; Hogan, Patrick G; Boyle, Mary; Burnham, Carey-Ann D; Fritz, Stephanie A

    2014-06-01

    Little is known about strain relatedness of methicillin-resistant Staphyloccocus aureus (MRSA) isolated at serial time points from the respiratory tract of patients with cystic fibrosis (CF). The objectives are to interrogate the genetic diversity of MRSA recovered in serial cultures from children with CF and to correlate strain relatedness with clinical characteristics. We performed a retrospective analysis of children with CF from whom MRSA was isolated from serial respiratory cultures from 2005 to 2011. Within individual patients, relatedness of isolated strains was determined by repetitive-sequence polymerase chain reaction, and the staphylococcal cassette chromosome mec type of each isolate was characterized. Medical records corresponding to the MRSA cultures were reviewed. We identified 54 CF patients with serial MRSA cultures (145 distinct cultures). Over time, 45 (83%) patients maintained the same strain type and 9 (17%) possessed at least 2 distinct strain types. A total of 91 pairs of isolates were analyzed for strain relatedness. Of these, 81 (89%) were identical and 10 (11%) were distinct strain types. About 117 (83%) isolates were staphylococcal cassette chromosome mec type II, 24 (17%) were staphylococcal cassette chromosome mec type IV and 4 were other types not resolvable with our assay. Clinical factors, including time interval and prescription of antibiotics effective against MRSA between positive cultures, did not correlate with acquisition of a distinct MRSA strain by individual patients. Our data suggest that sustained presence of MRSA in CF patients is most commonly attributable to identical strain types. Acquisition of distinct MRSA strains in the airway is infrequent.

  5. Dual Toxin-Producing Strain of Clostridium botulinum Type Bf Isolated from a California Patient with Infant Botulism

    PubMed Central

    Barash, Jason R.; Arnon, Stephen S.

    2004-01-01

    A retrospective study of Clostridium botulinum strains isolated from patients from California with infant botulism identified the fourth known C. botulinum strain that produces both type B and type F botulinum toxins. This unique strain represented 0.12% of the California infant botulism case isolates from 1976 to 2003. The relative concentrations of type B and F toxins produced were temperature dependent. PMID:15071029

  6. OpnS, an outer membrane porin of Xenorhabdus nematophila, confers a competitive advantage for growth in the insect host.

    PubMed

    van der Hoeven, Ransome; Forst, Steven

    2009-09-01

    The gammaproteobacterium Xenorhabdus nematophila engages in a mutualistic association with an entomopathogenic nematode and also functions as a pathogen toward different insect hosts. We studied the role of the growth-phase-regulated outer membrane protein OpnS in host interactions. OpnS was shown to be a 16-stranded beta-barrel porin. opnS was expressed during growth in insect hemolymph and expression was elevated as the cell density increased. When wild-type and opnS deletion strains were coinjected into insects, the wild-type strain was predominantly recovered from the insect cadaver. Similarly, an opnS-complemented strain outcompeted the DeltaopnS strain. Coinjection of the wild-type and DeltaopnS strains together with uncolonized nematodes into insects resulted in nematode progeny that were almost exclusively colonized with the wild-type strain. Likewise, nematode progeny recovered after coinjection of a mixture of nematodes carrying either the wild-type or DeltaopnS strain were colonized by the wild-type strain. In addition, the DeltaopnS strain displayed a competitive growth defect when grown together with the wild-type strain in insect hemolymph but not in defined culture medium. The DeltaopnS strain displayed increased sensitivity to antimicrobial compounds, suggesting that deletion of OpnS affected the integrity of the outer membrane. These findings show that the OpnS porin confers a competitive advantage for the growth and/or the survival of X. nematophila in the insect host and provides a new model for studying the biological relevance of differential regulation of porins in a natural host environment.

  7. Draft Genome Sequences of Mycobacterium setense Type Strain DSM-45070 and the Nonpathogenic Strain Manresensis, Isolated from the Bank of the Cardener River in Manresa, Catalonia, Spain

    PubMed Central

    Vilaplana, Cristina; Velasco, Juan; Pluvinet, Raquel; Santín, Sheila; Prat, Cristina; Julián, Esther; Alcaide, Fernando; Comas, Iñaki; Sumoy, Lauro; Cardona, Pere-Joan

    2015-01-01

    We present here the draft genome sequences of two Mycobacterium setense strains. One of them corresponds to the M. setense type strain DSM-45070, originally isolated from a patient with a posttraumatic chronic skin abscess. The other one corresponds to the nonpathogenic M. setense strain Manresensis, isolated from the Cardener River crossing Manresa, Catalonia, Spain. A comparative genomic analysis shows a smaller genome size and fewer genes in M. setense strain Manresensis relative to those of the type strain, and it shows the genome segments unique to each strain. PMID:25657273

  8. Emendation of Propionibacterium acnes subsp. acnes (Deiko et al. 2015) and proposal of Propionibacterium acnes type II as Propionibacterium acnes subsp. defendens subsp. nov.

    PubMed

    McDowell, Andrew; Barnard, Emma; Liu, Jared; Li, Huiying; Patrick, Sheila

    2016-12-01

    Recently, it has been proposed that strains of Propionibacterium acnes from the type III genetic division should be classified as P. acnessubsp. elongatum subsp. nov., with strains from the type I and II divisions collectively classified as P. acnessubsp. acnes subsp. nov. Under such a taxonomic re-appraisal, we believe that types I and II should also have their own separate rank of subspecies. In support of this, we describe a polyphasic taxonomic study based on the analysis of publicly available multilocus and whole-genome sequence datasets, alongside a systematic review of previously published phylogenetic, genomic, phenotypic and clinical data. Strains of types I and II form highly distinct clades on the basis of multilocus sequence analysis (MLSA) and whole-genome phylogenetic reconstructions. In silico or digital DNA-DNA similarity values also fall within the 70-80 % boundary recommended for bacterial subspecies. Furthermore, we see important differences in genome content, including the presence of an active CRISPR/Cas system in type II strains, but not type I, and evidence for increasing linkage equilibrium within the separate divisions. Key biochemical differences include positive test results for β-haemolytic, neuraminidase and sorbitol fermentation activities with type I strains, but not type II. We now propose that type I strains should be classified as P. acnessubsp. acnes subsp. nov., and type II as P. acnessubsp. defendens subsp. nov. The type strain of P. acnessubsp. acnes subsp. nov. is NCTC 737T (=ATCC 6919T=JCM 6425T=DSM 1897T=CCUG 1794T), while the type strain of P. acnessubsp. defendens subsp. nov. is ATCC 11828 (=JCM 6473=CCUG 6369).

  9. Mycobacterium leprae genomes from a British medieval leprosy hospital: towards understanding an ancient epidemic.

    PubMed

    Mendum, Tom A; Schuenemann, Verena J; Roffey, Simon; Taylor, G Michael; Wu, Huihai; Singh, Pushpendra; Tucker, Katie; Hinds, Jason; Cole, Stewart T; Kierzek, Andrzej M; Nieselt, Kay; Krause, Johannes; Stewart, Graham R

    2014-04-08

    Leprosy has afflicted humankind throughout history leaving evidence in both early texts and the archaeological record. In Britain, leprosy was widespread throughout the Middle Ages until its gradual and unexplained decline between the 14th and 16th centuries. The nature of this ancient endemic leprosy and its relationship to modern strains is only partly understood. Modern leprosy strains are currently divided into 5 phylogenetic groups, types 0 to 4, each with strong geographical links. Until recently, European strains, both ancient and modern, were thought to be exclusively type 3 strains. However, evidence for type 2 strains, a group normally associated with Central Asia and the Middle East, has recently been found in archaeological samples in Scandinavia and from two skeletons from the medieval leprosy hospital (or leprosarium) of St Mary Magdalen, near Winchester, England. Here we report the genotypic analysis and whole genome sequencing of two further ancient M. leprae genomes extracted from the remains of two individuals, Sk14 and Sk27, that were excavated from 10th-12th century burials at the leprosarium of St Mary Magdalen. DNA was extracted from the surfaces of bones showing osteological signs of leprosy. Known M. leprae polymorphisms were PCR amplified and Sanger sequenced, while draft genomes were generated by enriching for M. leprae DNA, and Illumina sequencing. SNP-typing and phylogenetic analysis of the draft genomes placed both of these ancient strains in the conserved type 2 group, with very few novel SNPs compared to other ancient or modern strains. The genomes of the two newly sequenced M. leprae strains group firmly with other type 2F strains. Moreover, the M. leprae strain most closely related to one of the strains, Sk14, in the worldwide phylogeny is a contemporaneous ancient St Magdalen skeleton, vividly illustrating the epidemic and clonal nature of leprosy at this site. The prevalence of these type 2 strains indicates that type 2F strains, in contrast to later European and associated North American type 3 isolates, may have been the co-dominant or even the predominant genotype at this location during the 11th century.

  10. Staphylococcus aureus strains associated with food poisoning outbreaks in France: comparison of different molecular typing methods, including MLVA

    PubMed Central

    Roussel, Sophie; Felix, Benjamin; Vingadassalon, Noémie; Grout, Joël; Hennekinne, Jacques-Antoine; Guillier, Laurent; Brisabois, Anne; Auvray, Fréderic

    2015-01-01

    Staphylococcal food poisoning outbreaks (SFPOs) are frequently reported in France. However, most of them remain unconfirmed, highlighting a need for a better characterization of isolated strains. Here we analyzed the genetic diversity of 112 Staphylococcus aureus strains isolated from 76 distinct SFPOs that occurred in France over the last 30 years. We used a recently developed multiple-locus variable-number tandem-repeat analysis (MLVA) protocol and compared this method with pulsed field gel electrophoresis (PFGE), spa-typing and carriage of genes (se genes) coding for 11 staphylococcal enterotoxins (i.e., SEA, SEB, SEC, SED, SEE, SEG, SEH, SEI, SEJ, SEP, SER). The strains known to have an epidemiological association with one another had identical MLVA types, PFGE profiles, spa-types or se gene carriage. MLVA, PFGE and spa-typing divided 103 epidemiologically unrelated strains into 84, 80, and 50 types respectively demonstrating the high genetic diversity of S. aureus strains involved in SFPOs. Each MLVA type shared by more than one strain corresponded to a single spa-type except for one MLVA type represented by four strains that showed two different-but closely related-spa-types. The 87 enterotoxigenic strains were distributed across 68 distinct MLVA types that correlated all with se gene carriage except for four MLVA types. The most frequent se gene detected was sea, followed by seg and sei and the most frequently associated se genes were sea-seh and sea-sed-sej-ser. The discriminatory ability of MLVA was similar to that of PFGE and higher than that of spa-typing. This MLVA protocol was found to be compatible with high throughput analysis, and was also faster and less labor-intensive than PFGE. MLVA holds promise as a suitable method for investigating SFPOs and tracking the source of contamination in food processing facilities in real time. PMID:26441849

  11. Major Change in the Predominant Type of “Norwalk-Like Viruses” in Outbreaks of Acute Nonbacterial Gastroenteritis in Osaka City, Japan, between April 1996 and March 1999

    PubMed Central

    Iritani, Nobuhiro; Seto, Yoshiyuki; Haruki, Kosuke; Kimura, Masatsugu; Ayata, Minoru; Ogura, Hisashi

    2000-01-01

    In Osaka City, Japan, between April 1996 and March 1999, a total of 350 fecal specimens from 64 outbreaks of acute nonbacterial gastroenteritis were examined to investigate infection by “Norwalk-like viruses” (NLVs). By reverse transcription (RT)-PCR, 182 samples (52.0%) from 47 outbreaks (73.4%) were NLV positive. During those three years, the incidence of NLV-associated outbreaks showed seasonality, being higher during January to March (winter to early spring). The ingestion of contaminated oysters was the most common transmission mode (42.6%). The amplicons of the 47 outbreak strains that were NLV positive by RT-PCR were tested using Southern hybridization with four probe sets (Ando et al., J. Clin. Microbiol. 33:64–71, 1995). Forty of the outbreak strains were classified as 4 probe 1-A (P1-A) strains, 6 P1-B strains, 10 P2-A strains, 17 P2-B strains, and 3 untypeable strains, and the other 7 outbreaks were determined to be mixed-probe-type strains. Probe typing and partial sequence analysis of the outbreak strains indicated that a predominant probe type of NLVs in Osaka City had drastically changed; P2-B strains (77.8%) with multiple genetic clusters were observed during the 1996–97 season, the P2-A common strain (81.3%) related to the Toronto virus cluster was observed during the 1997–98 season, and P1-B strains (75.0%) with a genetic similarity were observed during the 1998–99 season. For the three untypeable outbreak strains (96065, 97024, and 98026), the 98026 outbreak strain had Southampton virus (SOV)-like sequences, and each of the other outbreak strains had a unique 81-nucleotide sequence. Newly designed probes (SOV probe for the 98026 outbreak strain and the 96065 probe for the 96065 and 97024 outbreak strains) were hybridized with relative strains and without other probe type strains. The prevalent NLV probe types in Osaka City during those three years were classified in six phylogenetic groups: P1-A, P1-B, P2-A, P2-B, SOV, and 96065 probe types. PMID:10878058

  12. Genetic homogeneity of Clostridium botulinum type A1 strains with unique toxin gene clusters.

    PubMed

    Raphael, Brian H; Luquez, Carolina; McCroskey, Loretta M; Joseph, Lavin A; Jacobson, Mark J; Johnson, Eric A; Maslanka, Susan E; Andreadis, Joanne D

    2008-07-01

    A group of five clonally related Clostridium botulinum type A strains isolated from different sources over a period of nearly 40 years harbored several conserved genetic properties. These strains contained a variant bont/A1 with five nucleotide polymorphisms compared to the gene in C. botulinum strain ATCC 3502. The strains also had a common toxin gene cluster composition (ha-/orfX+) similar to that associated with bont/A in type A strains containing an unexpressed bont/B [termed A(B) strains]. However, bont/B was not identified in the strains examined. Comparative genomic hybridization demonstrated identical genomic content among the strains relative to C. botulinum strain ATCC 3502. In addition, microarray data demonstrated the absence of several genes flanking the toxin gene cluster among the ha-/orfX+ A1 strains, suggesting the presence of genomic rearrangements with respect to this region compared to the C. botulinum ATCC 3502 strain. All five strains were shown to have identical flaA variable region nucleotide sequences. The pulsed-field gel electrophoresis patterns of the strains were indistinguishable when digested with SmaI, and a shift in the size of at least one band was observed in a single strain when digested with XhoI. These results demonstrate surprising genomic homogeneity among a cluster of unique C. botulinum type A strains of diverse origin.

  13. Effects of enamel sealing on shear bond strength and the adhesive remnant index : Study of three fluoride-releasing adhesives in combination with metal and ceramic brackets.

    PubMed

    Hofmann, Elisabeth; Elsner, Laura; Hirschfelder, Ursula; Ebert, Thomas; Hanke, Sebastian

    2017-01-01

    Selected combinations of materials were used to create tooth-adhesive-bracket complexes to evaluate shear bond strength (SBS) and the adhesive remnant index (ARI) with regard to enamel sealing. Four adhesive systems also appropriate for use as enamel sealants were combined with four bracket types, resulting in 16 adhesive-bracket combinations, each of which was tested on 15 permanent bovine incisors. Sealant-adhesives included two recently introduced fluoride-releasing systems (Riva bond LC ® and go! ® ), one established primer (Opal ® Seal™), and one commonly used adhesive as control (Transbond™ XT). Brackets included two metal (discovery ® by Dentaurum and Sprint ® ) and two ceramic (discovery ® pearl and GLAM ® ) systems. After embedding the bovine teeth, bonding the brackets to their surface, and storing the resultant samples as per DIN 13990-2 with modifications, an SBS test was performed by applying the shear force directly at the bracket base in an incisocervical direction. Then the ARI scores were determined. Discovery ®  + Transbond™ XT yielded the highest (47.2 MPa) and GLAM ®  + go! ® the lowest (17.0 MPa) mean SBS values. Significant differences (p < 0.0001) were found between metal and ceramic brackets of the same manufacturers (Dentaurum and Forestadent). Our ratings of the failure modes upon debonding predominantly yielded ARI 0 or 1. The high SBS values and low ARI scores observed with discovery ®  + Transbond XT™ were reflected in a high rate of enamel fracture, which occurred on 11 of the 15 tooth specimens in this group. All sealant-bracket combinations were found to yield levels of SBS adequate for clinical application. SBS values and ARI scores varied significantly depending on which sealant-brackets were used.

  14. Increased riboflavin production from activated bleaching earth by a mutant strain of Ashbya gossypii.

    PubMed

    Tajima, Satoshi; Itoh, Yoko; Sugimoto, Takashi; Kato, Tatsuya; Park, Enoch Y

    2009-10-01

    The production of riboflavin from vegetable oil was increased using a mutant strain of Ashbya gossypii. This mutant was generated by treating the wild-type strain with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Riboflavin production was 10-fold higher in the mutant compared to the wild-type strain. The specific intracellular catalase activity after 3 d of culture was 6-fold higher in the mutant than in the wild-type strain. For the mutant, riboflavin production in the presence of 40 mM hydrogen peroxide was 16% less than that in the absence of hydrogen peroxide, whereas it was 56% less for the wild-type strain. The isocitrate lyase (ICL) activity of the mutant was 0.26 mU/mg of protein during the active riboflavin production phase, which was 2.6-fold higher than the wild-type strain. These data indicate that the mutant utilizes the carbon flux from the TCA cycle to the glyoxylate cycle more efficiently than the wild-type strain, resulting in enhanced riboflavin production. This novel mutant has the potential to be of use for industrial-scale riboflavin production from waste-activated bleaching earth (ABE), thereby transforming a useless material into a valuable bioproduct.

  15. Molecular epidemiology of tetM genes in Neisseria gonorrhoeae

    PubMed Central

    Turner, A.; Gough, K. R.; Leeming, J. P.

    1999-01-01

    OBJECTIVE: To examine the epidemiology of the tetM gene in Neisseria gonorrhoeae strains with high level resistance to tetracycline (TRNG) using a polymerase chain reaction (PCR) assay. METHODS: A single tube PCR was developed which distinguishes between the American and Dutch variants of the tetM gene. Between 1988 and 1995, 518 strains of TRNG (tetracycline MIC > 8.mg/l) were referred to the Gonococcus Reference Unit by other laboratories or isolated from routine swabs taken at local clinics. The strains were analysed for plasmid content, auxotype, serovar, and the tetM gene type. Travel details of the patients were determined by a questionnaire. RESULTS: A PCR product was obtained from all TRNG examined. 387 TRNG strains produced a 778 bp PCR product (American type tetM) and 131 produced a 443 by PCR product (Dutch type tetM). Infections acquired in the United Kingdom contributed 57% of the TRNG strains included in this study; 82% of these carried the American type of tetM. The number of UK acquired TRNG received by the GRU increased each year except 1993--from four strains received in 1990 to 92 in 1995. After the United Kingdom, Caribbean and African countries contributed most strains, with 56 and 60 TRNG acquired in each area respectively. All strains originating in Africa, except one from South Africa, contained the American type tetM. Infections caught in Nigeria and Kenya contributed most strains (15 and 14 respectively). The TRNG originating from Caribbean countries comprised 36% Dutch tetM type. Infections caught in Jamaica accounted for 82% of the Caribbean strains. All 35 TRNG strains originating in the Far East contained the Dutch type tetM. 25 of the Far East strains were also penicillinase producing (PPNG). Infections originating in Indonesia accounted for 49% of the Far East strains but these belonged to 12 different auxotype/serovar combinations. A geographical variation in the type of penicillinase coding plasmids found in PPNG/TRNG was also detected. CONCLUSIONS: These data suggest that the Dutch type tetM may have originated in the Far East and the American type in the African continent. Subsequent spread has resulted in a heterogeneous distribution of TRNG types in other parts of the world. At completion of the survey the numbers of TRNG imported each year from the major overseas sources had reached a plateau while UK contracted TRNG continued to rise providing evidence for the establishment of endemic TRNG strains in the United Kingdom. 


 PMID:10448346

  16. Differentiation between probiotic and wild-type Bacillus cereus isolates by antibiotic susceptibility test and Fourier transform infrared spectroscopy (FT-IR).

    PubMed

    Mietke, Henriette; Beer, W; Schleif, Julia; Schabert, G; Reissbrodt, R

    2010-05-30

    Animal feed often contains probiotic Bacillus strains used as feed additives. Spores of the non-pathogenic B. cereus var. toyoi (product name Toyocerin) are used. Distinguishing between toxic wild-type Bacillus cereus strains and this probiotic strain is essential for evaluating the quality and risk of feed. Bacillus cereus CIP 5832 (product name Paciflor was used as probiotic strain until 2001. The properties of the two probiotic strains are quite similar. Differentiating between probiotic strains and wild-type B. cereus strains is not easy. ss-lactam antibiotics such as penicillin and cefamandole exhibit an inhibition zone in the agar diffusion test of probiotic B. cereus strains which are not seen for wild-type strains. Therefore, performing the agar diffusion test first may make sense before FT-IR testing. When randomly checking these strains by Fourier transform infrared spectroscopy (FT-IR), the probiotic B. cereus strains were separated from wild-type B. cereus/B. thuringiensis/B. mycoides/B. weihenstephanensis strains by means of hierarchical cluster analysis. The discriminatory information was contained in the spectral windows 3000-2800 cm(-1) ("fatty acid region"), 1200-900 cm(-1) ("carbohydrate region") and 900-700 cm(-1) ("fingerprint region"). It is concluded that FT-IR spectroscopy can be used for the rapid quality control and risk analysis of animal feed containing probiotic B. cereus strains. (c) 2010 Elsevier B.V. All rights reserved.

  17. Association between Helicobacter pylori Virulence Factors and Gastroduodenal Diseases in Okinawa, Japan

    PubMed Central

    Matsunari, Osamu; Shiota, Seiji; Suzuki, Rumiko; Watada, Masahide; Kinjo, Nagisa; Murakami, Kazunari; Fujioka, Toshio; Kinjo, Fukunori

    2012-01-01

    The incidence of gastric cancer in Okinawa is lowest in Japan. Some previous reports using small number of strains suggested that the high prevalence of Helicobacter pylori with Western-type cagA in Okinawa compared to other areas in Japan might contribute to the low incidence of gastric cancer. It has still not been confirmed why the prevalence of Western-type cagA strains is high in Okinawa. We examined the association between the virulence factors of H. pylori and gastroduodenal diseases in Okinawa. The genotypes of cagA and vacA of 337 H. pylori strains were determined by PCR and gene sequencing. The genealogy of these Western-type cagA strains in Okinawa was analyzed by multilocus sequence typing (MLST). Overall, 86.4% of the strains possessed cagA: 70.3% were East-Asian type and 16.0% were Western type. After adjustment by age and sex, the presence of East-Asian-type cagA/vacA s1m1 genotypes was significantly associated with gastric cancer compared to gastritis (odds ratio = 6.68, 95% confidence interval = 1.73 to 25.8). The structure of Western-type CagA in Okinawa was different from that of typical Western-type CagA found in Western countries. Intriguingly, MLST analysis revealed that the majority of Western-type cagA strains formed individual clusters but not hpEurope. Overall, low prevalence of gastric cancer in Okinawa may result from the high prevalence of non-East-Asian-type cagA strains. The origin of Western-type cagA strains in Okinawa may be different from those of Western countries. PMID:22189111

  18. 75 FR 5039 - Notice of Intent to Prepare a Programmatic Environmental Impact Statement and Conduct Restoration...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-01

    ... scheduled as follows: Wednesday, March 3, 2010, 6-8 p.m., City of Portland's Water Pollution Control... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration RIN 0648-XT38 Notice of... Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce. ACTION: Notice of intent...

  19. Interfacing Optical Document Scanners: Principles and Practical Considerations.

    ERIC Educational Resources Information Center

    Krus, David J.; Kodimer, Dennis

    1987-01-01

    Handlers for interfacing the ScanTron and 2700 Optical Mark Readers with the IBM AT/XT/PC and Tandy 2000/1000/3000 iAPX 88/186/286 based computers were described. Differences between programing an RS232C serial port using BIOS interrupts and directly addressing the Motorola 8550 ART microprocessor were discussed. (Author/LMO)

  20. 75 FR 59154 - Fisheries of the Northeastern United States; Black Sea Bass Fishery; 2010 Black Sea Bass...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-27

    .... 100120036-0360-02] RIN 0648-XT99 Fisheries of the Northeastern United States; Black Sea Bass Fishery; 2010 Black Sea Bass Specifications; Emergency Rule Extension; Correction AGENCY: National Marine Fisheries... emergency action to increase the 2010 black sea bass specifications. The preamble text of that rule...

  1. 75 FR 38935 - Fisheries of the Northeastern United States; Black Sea Bass Fishery; 2010 Black Sea Bass...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-07

    ...--XT99 [Docket No. 100120036-0038-01] Fisheries of the Northeastern United States; Black Sea Bass Fishery; 2010 Black Sea Bass Specifications; Emergency Rule Extension AGENCY: National Marine Fisheries Service...; emergency action extension. SUMMARY: NMFS is extending the emergency action to increase the 2010 black sea...

  2. 75 FR 6586 - Fisheries of the Northeastern United; Black Sea Bass Fishery; 2010 Black Sea Bass Specifications...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-10

    ...-XT99 [Docket No. 100120036-0038-01] Fisheries of the Northeastern United; Black Sea Bass Fishery; 2010 Black Sea Bass Specifications; Emergency Rule AGENCY: National Marine Fisheries Service (NMFS), National... sea bass specifications (i.e., commercial fishing quota, recreational harvest limit (RHL), and...

  3. 77 FR 14517 - Southern Star Central Gas Pipeline, Inc.; Notice of Request Under Blanket Authorization

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-12

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. CP12-73-000] Southern Star..., 2012 Southern Star Central Gas Pipeline, Inc. (Southern Star), 4700 State Highway 56, Owensboro... Star proposes to replace 3 miles of 12-inch diameter XT pipeline by constructing approximately 3 miles...

  4. 75 FR 8053 - Southern Star Central Gas Pipeline, Inc.; Notice of Request Under Blanket Authorization

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-23

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. CP10-48-000] Southern Star... that on January 29, 2010, Southern Star Central Gas Pipeline, Inc. (Southern Star), 4700 State Highway... TTY, (202) 502-8659. Specifically, Southern Star proposes to replace two miles of 12- inch diameter XT...

  5. Portable Powerhouses.

    ERIC Educational Resources Information Center

    Myslewski, Rik; Garcia, Nathan

    1998-01-01

    Reviews and compares the following nine laptop computers, focusing on their capabilities for multimedia presentations: Apple Macintosh PowerBook G3, Chem USA ChemBook 9780, Compaq Armada 7792DMT, Dell Inspiron 3000 mZ66xT, Hewlett-Packard OmniBook 3000CTX, IBM ThinkPad 770, Micro Express NP8233MMX, NEC Versa 6260, and Panasonic CF-63. Evaluation…

  6. 77 FR 40083 - Certain Personal Data and Mobile Communications Devices and Related Software; Institution of a...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-06

    ... Communications Devices and Related Software; Institution of a Formal Enforcement Proceeding; Denial of Request... subsidiary NeXT Software, Inc., both of Cupertino, California (collectively, ``Apple''), alleging a violation... importation of certain personal data and mobile communications devices and related software. 75 FR 17434 (Apr...

  7. 75 FR 2820 - Fisheries of the Northeastern United States; Summer Flounder Fishery; Quota Transfer

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-19

    .... 0809251266-81485-02] RIN 0648-XT61 Fisheries of the Northeastern United States; Summer Flounder Fishery... of North Carolina is transferring a portion of its 2009 commercial summer flounder quota to the...: Regulations governing the summer flounder fishery are found at 50 CFR part 648. The regulations require annual...

  8. ERDC MSRC (Major Shared Resource Center) Resource. Spring 2008

    DTIC Science & Technology

    2008-01-01

    obtained from ADCIRC results. The alpha test was performed on the Cray XT3 machine (Sapphire) at ERDC and the IBM P575+ system ( Babbage ) at the...2008 20 Scotty Swillie (center) and Charles Ray (far right) were part of the team that constructed the DoD HPCMP booth for the Conference (From

  9. Shock Waves in a Bose-Einstein Condensate

    NASA Technical Reports Server (NTRS)

    Kulikov, Igor; Zak, Michail

    2005-01-01

    A paper presents a theoretical study of shock waves in a trapped Bose-Einstein condensate (BEC). The mathematical model of the BEC in this study is a nonlinear Schroedinger equation (NLSE) in which (1) the role of the wave function of a single particle in the traditional Schroedinger equation is played by a space- and time-dependent complex order parameter (x,t) proportional to the square root of the density of atoms and (2) the atoms engage in a repulsive interaction characterized by a potential proportional to | (x,t)|2. Equations that describe macroscopic perturbations of the BEC at zero temperature are derived from the NLSE and simplifying assumptions are made, leading to equations for the propagation of sound waves and the transformation of sound waves into shock waves. Equations for the speeds of shock waves and the relationships between jumps of velocity and density across shock fronts are derived. Similarities and differences between this theory and the classical theory of sound waves and shocks in ordinary gases are noted. The present theory is illustrated by solving the equations for the example of a shock wave propagating in a cigar-shaped BEC.

  10. Quantifying phase synchronization using instances of Hilbert phase slips

    NASA Astrophysics Data System (ADS)

    Govindan, R. B.

    2018-07-01

    We propose to quantify phase synchronization between two signals, x(t) and y(t), by calculating variance in the Hilbert phase of y(t) at instances of phase slips exhibited by x(t). The proposed approach is tested on numerically simulated coupled chaotic Roessler systems and second order autoregressive processes. Furthermore we compare the performance of the proposed and original approaches using uterine electromyogram signals and show that both approaches yield consistent results A standard phase synchronization approach, which involves unwrapping the Hilbert phases (ϕ1(t) and ϕ2(t)) of the two signals and analyzing the variance in the | n ṡϕ1(t) - m ṡϕ2(t) | , mod 2 π, (n and m are integers), was used for comparison. The synchronization indexes obtained from the proposed approach and the standard approach agree reasonably well in all of the systems studied in this work. Our results indicate that the proposed approach, unlike the traditional approach, does not require the non-invertible transformations - unwrapping of the phases and calculation of mod 2 π and it can be used to reliably to quantify phase synchrony between two signals.

  11. Improving Forecasts Through Realistic Uncertainty Estimates: A Novel Data Driven Method for Model Uncertainty Quantification in Data Assimilation

    NASA Astrophysics Data System (ADS)

    Pathiraja, S. D.; Moradkhani, H.; Marshall, L. A.; Sharma, A.; Geenens, G.

    2016-12-01

    Effective combination of model simulations and observations through Data Assimilation (DA) depends heavily on uncertainty characterisation. Many traditional methods for quantifying model uncertainty in DA require some level of subjectivity (by way of tuning parameters or by assuming Gaussian statistics). Furthermore, the focus is typically on only estimating the first and second moments. We propose a data-driven methodology to estimate the full distributional form of model uncertainty, i.e. the transition density p(xt|xt-1). All sources of uncertainty associated with the model simulations are considered collectively, without needing to devise stochastic perturbations for individual components (such as model input, parameter and structural uncertainty). A training period is used to derive the distribution of errors in observed variables conditioned on hidden states. Errors in hidden states are estimated from the conditional distribution of observed variables using non-linear optimization. The theory behind the framework and case study applications are discussed in detail. Results demonstrate improved predictions and more realistic uncertainty bounds compared to a standard perturbation approach.

  12. Controlled release of Lactobacillus rhamnosus biofilm probiotics from alginate-locust bean gum microcapsules.

    PubMed

    Cheow, Wean Sin; Kiew, Tie Yi; Hadinoto, Kunn

    2014-03-15

    Chitosan-coated alginate microcapsules containing high-density biofilm Lactobacillus rhamnosus have been previously shown to exhibit higher freeze drying- and thermal-tolerance than their planktonic counterparts. However, their cell release profile remains poor due to the capsules' susceptibility to the gastric environment. Herein the effects of adding locust bean (LB) and xanthan (XT) gums to alginate (AGN) capsules on the stress tolerance and cell release profiles in simulated gastrointestinal fluids are investigated. Compared to the AGN-only capsules, the AGN-LB capsules exhibit improved stress tolerance (i.e. ≈ 6x for freeze drying, 100x for thermotolerance, 10x for acid), whereas the AGN-XT capsules only improve the acid tolerance. Importantly, the AGN-LB capsules possess the optimal cell release profile with a majority of cells released in the simulated intestinal juice than in the gastric juice. The AGN-LB capsules' superiority is attributed to their stronger interaction with the chitosan coating and high swelling capacity, thus delaying their bulk dissolution. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. The Spider Center Wide File System; From Concept to Reality

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shipman, Galen M; Dillow, David A; Oral, H Sarp

    2009-01-01

    The Leadership Computing Facility (LCF) at Oak Ridge National Laboratory (ORNL) has a diverse portfolio of computational resources ranging from a petascale XT4/XT5 simulation system (Jaguar) to numerous other systems supporting development, visualization, and data analytics. In order to support vastly different I/O needs of these systems Spider, a Lustre-based center wide file system was designed and deployed to provide over 240 GB/s of aggregate throughput with over 10 Petabytes of formatted capacity. A multi-stage InfiniBand network, dubbed as Scalable I/O Network (SION), with over 889 GB/s of bisectional bandwidth was deployed as part of Spider to provide connectivity tomore » our simulation, development, visualization, and other platforms. To our knowledge, while writing this paper, Spider is the largest and fastest POSIX-compliant parallel file system in production. This paper will detail the overall architecture of the Spider system, challenges in deploying and initial testings of a file system of this scale, and novel solutions to these challenges which offer key insights into file system design in the future.« less

  14. Size-expanded DNA bases: An ab-initio study of their structural and electronic properties

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fuentes-Cabrera, Miguel A; Sumpter, Bobby G; Wells, Jack C

    2005-01-01

    The size-expanded DNA bases, xA, xC, xG, and xT, are benzo-homologue forms of the natural DNA bases; i.e., their structure can be seen as the fusion of a natural base and a benzene ring. Recently, a variety of DNAs, known as xDNAs, have been synthesized in which size-expanded and natural bases are paired. In this paper we use second-order Moeller-Plesset perturbation theory and density functional theory to investigate the structural and electronic properties of xA, xC, xG, and xT and their natural counterparts. We find that whereas natural and size-expanded bases have both nonplanar amino groups the latter have alsomore » nonplanar aromatic rings. When density functional theory is used to investigate the electronic properties of size-expanded and natural bases, it is found that the HOMO-LUMO gap of the size-expanded bases is smaller than that of the natural bases. Also, xG should be easier to oxidize than G.« less

  15. Separation of components from a scale mixture of Gaussian white noises

    NASA Astrophysics Data System (ADS)

    Vamoş, Călin; Crăciun, Maria

    2010-05-01

    The time evolution of a physical quantity associated with a thermodynamic system whose equilibrium fluctuations are modulated in amplitude by a slowly varying phenomenon can be modeled as the product of a Gaussian white noise {Zt} and a stochastic process with strictly positive values {Vt} referred to as volatility. The probability density function (pdf) of the process Xt=VtZt is a scale mixture of Gaussian white noises expressed as a time average of Gaussian distributions weighted by the pdf of the volatility. The separation of the two components of {Xt} can be achieved by imposing the condition that the absolute values of the estimated white noise be uncorrelated. We apply this method to the time series of the returns of the daily S&P500 index, which has also been analyzed by means of the superstatistics method that imposes the condition that the estimated white noise be Gaussian. The advantage of our method is that this financial time series is processed without partitioning or removal of the extreme events and the estimated white noise becomes almost Gaussian only as result of the uncorrelation condition.

  16. Genetic differentiation of methicillin-resistant Staphylococcus aureus strains from Korea and Japan.

    PubMed

    Soo Ko, Kwan; Peck, Kyong Ran; Sup Oh, Won; Lee, Nam Yong; Hiramatsu, Keiichi; Song, Jae-Hoon

    2005-01-01

    In this study, we evaluated genetic differentiation between methicillin-resistant Staphylococcus aureus (MRSA) strains from Korea and Japan. Seventy-five MRSA strains, including 25 h VISA strains, were analyzed by molecular typing methods, including multilocus sequence typing (MLST), SCC mec typing, and spa typing. The most prevalent genotype of MRSA strains, in both Korea and Japan, was ST 5-MRSA-II with the DMGMK spa motif, characteristic of the New York/Japan MRSA clone. In spite of these common features in MRSA strains from Korea and Japan, we also observed some genotypic divergence in MRSA from the two countries. Several spa types might be differentiated from a prevalent prototype (TJMBMDMGMK) that is shared by the two countries, revealing a unique geographic distribution. SCC mec type II lacking pUB110, designated type IIA, was found more frequently in Korea than in Japan. The rate of gentamicin resistance was also dramatically different between the two countries: 87.2% (Korea) vs. 28.6% (Japan). These preliminary findings suggested that MRSA strains from Korea and Japan might have originated from a common ancestor, but then clearly differentiated according to locality. A further comprehensive study should be performed to document the hypotheses from this study.

  17. OpnS, an Outer Membrane Porin of Xenorhabdus nematophila, Confers a Competitive Advantage for Growth in the Insect Host▿ †

    PubMed Central

    van der Hoeven, Ransome; Forst, Steven

    2009-01-01

    The gammaproteobacterium Xenorhabdus nematophila engages in a mutualistic association with an entomopathogenic nematode and also functions as a pathogen toward different insect hosts. We studied the role of the growth-phase-regulated outer membrane protein OpnS in host interactions. OpnS was shown to be a 16-stranded β-barrel porin. opnS was expressed during growth in insect hemolymph and expression was elevated as the cell density increased. When wild-type and opnS deletion strains were coinjected into insects, the wild-type strain was predominantly recovered from the insect cadaver. Similarly, an opnS-complemented strain outcompeted the ΔopnS strain. Coinjection of the wild-type and ΔopnS strains together with uncolonized nematodes into insects resulted in nematode progeny that were almost exclusively colonized with the wild-type strain. Likewise, nematode progeny recovered after coinjection of a mixture of nematodes carrying either the wild-type or ΔopnS strain were colonized by the wild-type strain. In addition, the ΔopnS strain displayed a competitive growth defect when grown together with the wild-type strain in insect hemolymph but not in defined culture medium. The ΔopnS strain displayed increased sensitivity to antimicrobial compounds, suggesting that deletion of OpnS affected the integrity of the outer membrane. These findings show that the OpnS porin confers a competitive advantage for the growth and/or the survival of X. nematophila in the insect host and provides a new model for studying the biological relevance of differential regulation of porins in a natural host environment. PMID:19465651

  18. Prevalence and Characterization of Oxacillin Susceptible mecA-Positive Clinical Isolates of Staphylococcus aureus Causing Bovine Mastitis in India.

    PubMed

    Mistry, Hiral; Sharma, Paresh; Mahato, Sudipta; Saravanan, R; Kumar, P Anand; Bhandari, Vasundhra

    2016-01-01

    Bovine mastitis caused by multidrug resistant Staphylococcus aureus is a huge problem reported worldwide, resulting in prolonged antibiotic treatment and death of livestock. The current study is focused on surveillance of antibiotic susceptibility along with genotypic and phenotypic characterization of the pathogenic S. aureus strains causing mastitis in India. One hundred and sixty seven milk samples were collected from mastitis-affected cows from different farms in India resulting in thirty nine isolated S. aureus strains. Antibiotic sensitivity profiling revealed the majority of the strains (n = 24) to be multidrug resistant and eleven strains showed reduced susceptibility to vancomycin (MICs = 2μg/ml). All strains were oxacillin sensitive, but 19 strains were positive for the mecA gene, which revealed the occurrence of oxacillin susceptible mecA positive strains (OS-MRSA) for the first time from India. Additionally, 32 strains were positive for the pvl gene, a virulence determinant; of these 17 were also OS-MRSA strains. Molecular characterization based on multilocus sequence typing (MLST), spa typing, agr typing and SCCmec classification revealed strains belonging to different groups. Moreover, strains showed spa types (t2526, t9602) and MLST sequence types, ST-72, ST-88 and ST-239 which have been earlier reported in human infections. The prevalence of OS-MRSA strains indicates the importance of including both the genetic and phenotypic tests in characterizing S. aureus strains. Increased genotypic variability with strain related to human infections and pvl positive isolates indicates a worrisome situation with the possibility of bilateral transfer.

  19. Pyocine typing as an epidemiological marker in Pseudomonas aeruginosa mastitis in cattle

    PubMed Central

    Ziv, G.; Mushin, Rose; Tagg, J. R.

    1971-01-01

    Pyocine typing was used for the characterization of 134 Pseudomonas aeruginosa strains isolated from bovine mastitis. The scheme of Gillies & Govan (1966) was adopted with some modifications, and the procedure gave 89·6% typability. Pyocine type 1 strains were most commonly encountered and were followed in frequency by types 10 and 3. The introduction of two additional indicator strains allowed for division of these types into subtypes. In spite of some limitations, discussed in the paper, the pyocine typing scheme proved to be useful in `marking' P. aeruginosa strains and in following their association with bovine mastitis in various herds. PMID:4996924

  20. Comparison of Genomic Methods for Differentiating Strains of Enterococcus faecium: Assessment Using Clinical Epidemiologic Data

    PubMed Central

    Savor, Connie; Pfaller, Michael A.; Kruszynski, Julie A.; Hollis, Richard J.; Noskin, Gary A.; Peterson, Lance R.

    1998-01-01

    Genomic DNA extracted from 45 vancomycin-resistant Enterococcus faecium (VRE) isolates was cleaved with HindIII and HaeIII and subjected to agarose gel electrophoresis. The ability of this method (restriction endonuclease analysis [REA]) to distinguish strains at the subspecies level was compared with results previously determined by pulsed-field gel electrophoresis (PFGE). Chart reviews were performed to provide a clinical correlation of possible epidemiologic relatedness. A likely clinical association was found for 29 patients as part of two outbreaks. REA found 21 of 21 isolates were the same type in the first outbreak, with PFGE calling 19 strains the same type. In the second outbreak with eight patient isolates, HindIII found six were the same type and two were unique types. HaeIII found three strains were the same type, two strains were a separate type, and three more strains were unique types, while PFGE found three were the same type and five were unique types. No single “ideal” method can be used without clinical epidemiologic investigation, but any of these techniques is helpful in providing focus to infection control practitioners assessing possible outbreaks of nosocomial infection. PMID:9774587

  1. Susceptibility of ocean- and stream-type Chinook salmon to isolates of the L, U, and M genogroups of infectious hematopoietic necrosis virus (IHNV)

    USGS Publications Warehouse

    Hernandez, Daniel; Purcell, Maureen K.; Friedman, Carolyn S.; Kurath, Gael

    2016-01-01

    This study examined the susceptibility of Chinook salmon Oncorhynchus tshawytscha to viral strains from the L, U, and M genogroups of infectious hematopoietic necrosis virus (IHNV) present in western North America. The goal of this investigation was to establish a baseline understanding of the susceptibility of ocean- and stream-type Chinook salmon to infection and mortality caused by exposure to commonly detected strains of L, U, and M IHNV. The L IHNV strain tested here was highly infectious and virulent in both Chinook salmon populations, following patterns previously reported for Chinook salmon. Furthermore, ocean- and stream-type Chinook salmon fry at 1 g can also become subclinically infected with U and M strains of IHNV without experiencing significant mortality. The stream-type life history phenotype was generally more susceptible to infection and suffered greater mortality than the ocean-type phenotype. Between the U and M genogroup strains tested, the U group strains were generally more infectious than the M group strains in both Chinook salmon types. Substantial viral clearance occurred by 30 d post exposure, but persistent viral infection was observed with L, U, and M strains in both host populations. While mortality decreased with increased host size in stream-type Chinook salmon, infection prevalence was not lower for all strains at a greater size. These results suggest that Chinook salmon may serve as reservoirs and/or vectors of U and M genogroup IHNV.

  2. Susceptibility of ocean- and stream-type Chinook salmon to isolates of the L, U, and M genogroups of infectious hematopoietic necrosis virus (IHNV).

    PubMed

    Hernandez, Daniel G; Purcell, Maureen K; Friedman, Carolyn S; Kurath, Gael

    2016-08-31

    This study examined the susceptibility of Chinook salmon Oncorhynchus tshawytscha to viral strains from the L, U, and M genogroups of infectious hematopoietic necrosis virus (IHNV) present in western North America. The goal of this investigation was to establish a baseline understanding of the susceptibility of ocean- and stream-type Chinook salmon to infection and mortality caused by exposure to commonly detected strains of L, U, and M IHNV. The L IHNV strain tested here was highly infectious and virulent in both Chinook salmon populations, following patterns previously reported for Chinook salmon. Furthermore, ocean- and stream-type Chinook salmon fry at 1 g can also become subclinically infected with U and M strains of IHNV without experiencing significant mortality. The stream-type life history phenotype was generally more susceptible to infection and suffered greater mortality than the ocean-type phenotype. Between the U and M genogroup strains tested, the U group strains were generally more infectious than the M group strains in both Chinook salmon types. Substantial viral clearance occurred by 30 d post exposure, but persistent viral infection was observed with L, U, and M strains in both host populations. While mortality decreased with increased host size in stream-type Chinook salmon, infection prevalence was not lower for all strains at a greater size. These results suggest that Chinook salmon may serve as reservoirs and/or vectors of U and M genogroup IHNV.

  3. The combined effect of food-simulating solutions, brushing and staining on color stability of composite resins

    PubMed Central

    Silva, Tânia Mara Da; Sales, Ana Luísa Leme Simões; Pucci, Cesar Rogerio; Borges, Alessandra Bühler; Torres, Carlos Rocha Gomes

    2017-01-01

    Abstract Objective: This study evaluated the effect of food-simulating media associated with brushing and coffee staining on color stability of different composite resins. Materials and methods: Eighty specimens were prepared for each composite: Grandio SO (Voco), Amaris (Voco), Filtek Z350XT (3M/ESPE), Filtek P90 (3M/ESPE). They were divided into four groups according to food-simulating media for 7 days: artificial saliva (control), heptane, citric acid and ethanol. The composite surface was submitted to 10,950 brushing cycles (200 g load) in an automatic toothbrushing machine. The specimens were darkened with coffee solution at 37 °C for 24 h. After each treatment, color measurements were assessed by spectrophotometry, using CIE L*a*b* system. The overall color change (ΔE) was determined for each specimen at baseline (C1) and after the treatments (food-simulating media immersion/C2, brushing/C3 and dye solution/C4). Data were analyzed by two-way repeated measures ANOVA and Tukey’s tests (p < .05). Results: The results of RM-ANOVA showed significant differences for composites (p = .001), time (p = .001) and chemical degradation (p = .002). The mean of ΔE for composites were: Z350XT (5.39)a, Amaris (3.89)b, Grandio (3.75)bc, P90 (3.36)c. According to food-simulating media: heptane (4.41)a, citric acid (4.24)a, ethanol (4.02)ab, artificial saliva (3.76)b. For the treatments: dye solution (4.53)a, brushing (4.26)a, after food-simulating media (3.52)b. Conclusions: The composite resin Filtek Z350XT showed significantly higher staining than all other composite resin tested. The immersion in heptane and citric acid produced the highest color alteration than other food-simulating media. The exposure of samples to brushing protocols and darkening in coffee solution resulted in significant color alteration of the composite resins. PMID:28642926

  4. Influence of Er:YAG and Ti:sapphire laser irradiation on the microtensile bond strength of several adhesives to dentin.

    PubMed

    Portillo, M; Lorenzo, M C; Moreno, P; García, A; Montero, J; Ceballos, L; Fuentes, M V; Albaladejo, A

    2015-02-01

    The aim of the present study was to evaluate the influence of erbium:yttrium-aluminum-garnet (Er:YAG) and Ti:sapphire laser irradiation on the microtensile bond strength (MTBS) of three different adhesive systems to dentin. Flat dentin surfaces from 27 molars were divided into three groups according to laser irradiation: control, Er:YAG (2,940 nm, 100 μs, 2.7 W, 9 Hz) and Ti:sapphire laser (795 nm, 120 fs, 1 W, 1 kHz). Each group was divided into three subgroups according to the adhesive system used: two-step total-etching adhesive (Adper Scotchbond 1 XT, from now on XT), two-step self-etching adhesive (Clearfil SE Bond, from now on CSE), and all-in-one self-etching adhesive (Optibond All-in-One, from now on OAO). After 24 h of water storage, beams of section at 1 mm(2) were longitudinally cut from the samples. Each beam underwent traction test in an Instron machine. Fifteen polished dentin specimens were used for the surface morphology analysis by scanning electron microscopy (SEM). Failure modes of representative debonded microbars were SEM-assessed. Data were analyzed by ANOVA, chi-square test, and multiple linear regression (p < 0.05). In the control group, XT obtained higher MTBS than that of laser groups that performed equally. CSE showed higher MTBS without laser than that with laser groups, where Er:YAG attained higher MTBS than ultrashort laser. When OAO was used, MTBS values were equal in the three treatments. CSE obtained the highest MTBS regardless of the surface treatment applied. The Er:YAG and ultrashort laser irradiation reduce the bonding effectiveness when a two-step total-etching adhesive or a two-step self-etching adhesive are used and do not affect their effectiveness when an all-in-one self-etching adhesive is applied.

  5. London penetration depth measurements in Ba (Fe 1-xT x) 2As 2(T=Co,Ni,Ru,Rh,Pd,Pt,Co+Cu) superconductors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gordon, Ryan T.

    2011-01-01

    The London penetration depth has been measured in various doping levels of single crystals of Ba(Fe 1-xT x) 2As 2 (T=Co,Ni,Ru,Rh,Pd,Pt,Co+Cu) superconductors by utilizing a tunnel diode resonator (TDR) apparatus. All in-plane penetration depth measurements exhibit a power law temperature dependence of the form Δλ ab(T) = CT n, indicating the existence of low-temperature, normal state quasiparticles all the way down to the lowest measured temperature, which was typically 500 mK. Several different doping concentrations from the Ba(Fe 1-xT x) 2As 2 (T=Co,Ni) systems have been measured and the doping dependence of the power law exponent, n, is compared tomore » results from measurements of thermal conductivity and specific heat. In addition, a novel method has been developed to allow for the measurement of the zero temperature value of the in-plane penetration depth, λ ab(0), by using TDR frequency shifts. By using this technique, the doping dependence of λ ab(0) has been measured in the Ba(Fe 1-xCo x) 2As 2 series, which has allowed also for the construction of the doping-dependent superfluid phase stiffness, ρ s(T) = [λ(0)/λ(T)] 2. By studying the effects of disorder on these superconductors using heavy ion irradiation, it has been determined that the observed power law temperature dependence likely arises from pair-breaking impurity scattering contributions, which is consistent with the proposed s±-wave symmetry of the superconducting gap in the dirty scattering limit. This hypothesis is supported by the measurement of an exponential temperature dependence of the penetration depth in the intrinsically clean LiFeAs, indicative of a nodeless superconducting gap.« less

  6. A 4-year clinical evaluation of direct composite build-ups for space closure after orthodontic treatment.

    PubMed

    Demirci, Mustafa; Tuncer, Safa; Öztaş, Evren; Tekçe, Neslihan; Uysal, Ömer

    2015-12-01

    To evaluate the medium-term clinical performance of direct composite build-ups for diastema closures and teeth recontouring using a nano and a nanohybrid composite in combination with three- or two-step etch-and-rinse adhesives following treatment with fixed orthodontic appliances. A total of 30 patients (mean age, 19.5 years) received 147 direct composite additions for teeth recontouring and diastema closures. A nano and a nanohybrid composite (Filtek Supreme XT and CeramX Duo) were bonded to tooth structure by using a three-step (Scotchbond Multipurpose) or a two-step (XP Bond) etch and rinse adhesive. Ten out of 147 composite build-ups (composite addition) constituted tooth recontouring cases, and the remaining 137 constituted diastema closure cases. The restorations were evaluated by two experienced, calibrated examiners according to modified Ryge criteria at the following time intervals: baseline, 1, 2, 3, and 4 years. The 4-year survival rates were 92.8 % for Filtek Supreme XT/Scotchbond Multi-Purpose Plus and 93 % for CeramX Duo/XP Bond. Only ten restorations failed (5 Filtek Supreme XT and 5 CeramX Duo). Statistical analysis revealed no significant differences between the two composite-adhesive combinations with respect to color match, marginal discoloration, wear/loss of anatomical form, caries formation, marginal adaptation, and surface texture on comparing the five time periods (baseline, 1, 2, 3, and 4 years) The 4-year survival rates in the present study were favorable. The restorations exhibited excellent scores with regard to color match, marginal adaptation, surface texture, marginal discoloration, wear/loss of anatomical form, and caries formation, after 4 years of clinical evaluation. Clinical relevance An alternative clinical approach for correcting discrepancies in tooth size and form, such as performing direct composite restorations following fixed orthodontic treatment, may be an excellent and minimally invasive treatment.

  7. System and method for constructing filters for detecting signals whose frequency content varies with time

    DOEpatents

    Qian, S.; Dunham, M.E.

    1996-11-12

    A system and method are disclosed for constructing a bank of filters which detect the presence of signals whose frequency content varies with time. The present invention includes a novel system and method for developing one or more time templates designed to match the received signals of interest and the bank of matched filters use the one or more time templates to detect the received signals. Each matched filter compares the received signal x(t) with a respective, unique time template that has been designed to approximate a form of the signals of interest. The robust time domain template is assumed to be of the order of w(t)=A(t)cos(2{pi}{phi}(t)) and the present invention uses the trajectory of a joint time-frequency representation of x(t) as an approximation of the instantaneous frequency function {phi}{prime}(t). First, numerous data samples of the received signal x(t) are collected. A joint time frequency representation is then applied to represent the signal, preferably using the time frequency distribution series. The joint time-frequency transformation represents the analyzed signal energy at time t and frequency f, P(t,f), which is a three-dimensional plot of time vs. frequency vs. signal energy. Then P(t,f) is reduced to a multivalued function f(t), a two dimensional plot of time vs. frequency, using a thresholding process. Curve fitting steps are then performed on the time/frequency plot, preferably using Levenberg-Marquardt curve fitting techniques, to derive a general instantaneous frequency function {phi}{prime}(t) which best fits the multivalued function f(t). Integrating {phi}{prime}(t) along t yields {phi}{prime}(t), which is then inserted into the form of the time template equation. A suitable amplitude A(t) is also preferably determined. Once the time template has been determined, one or more filters are developed which each use a version or form of the time template. 7 figs.

  8. Subcompartment localization of the side chain xyloglucan-synthesizing enzymes within Golgi stacks of tobacco suspension-cultured cells.

    PubMed

    Chevalier, Laurence; Bernard, Sophie; Ramdani, Yasmina; Lamour, Romain; Bardor, Muriel; Lerouge, Patrice; Follet-Gueye, Marie-Laure; Driouich, Azeddine

    2010-12-01

    Xyloglucan is the dominant hemicellulosic polysaccharide of the primary cell wall of dicotyledonous plants that plays a key role in plant development. It is well established that xyloglucan is assembled within Golgi stacks and transported in Golgi-derived vesicles to the cell wall. It is also known that the biosynthesis of xyloglucan requires the action of glycosyltransferases including α-1,6-xylosyltransferase, β-1,2-galactosyltransferase and α-1,2-fucosyltransferase activities responsible for the addition of xylose, galactose and fucose residues to the side chains. There is, however, a lack of knowledge on how these enzymes are distributed within subcompartments of Golgi stacks. We have undertaken a study aiming at mapping these glycosyltransferases within Golgi stacks using immunogold-electron microscopy. To this end, we generated transgenic lines of tobacco (Nicotiana tabacum) BY-2 suspension-cultured cells expressing either the α-1,6-xylosyltransferase, AtXT1, the β-1,2-galactosyltransferase, AtMUR3, or the α-1,2-fucosyltransferase AtFUT1 of Arabidopsis thaliana fused to green-fluorescent protein (GFP). Localization of the fusion proteins within the endomembrane system was assessed using confocal microscopy. Additionally, tobacco cells were high pressure-frozen/freeze-substituted and subjected to quantitative immunogold labelling using anti-GFP antibodies to determine the localization patterns of the enzymes within subtypes of Golgi cisternae. The data demonstrate that: (i) all fusion proteins, AtXT1-GFP, AtMUR3-GFP and AtFUT1-GFP are specifically targeted to the Golgi apparatus; and (ii) AtXT1-GFP is mainly located in the cis and medial cisternae, AtMUR3-GFP is predominantly associated with medial cisternae and AtFUT1-GFP mostly detected over trans cisternae suggesting that initiation of xyloglucan side chains occurs in early Golgi compartments in tobacco cells. The Plant Journal © 2010 Blackwell Publishing Ltd. No claim to original US government works.

  9. Effect of light-curable fluoride varnish on enamel demineralization adjacent to orthodontic brackets: an in-vivo study.

    PubMed

    Mehta, Anurag; Paramshivam, Ganesh; Chugh, Vinay Kumar; Singh, Surjit; Halkai, Sudha; Kumar, Santosh

    2015-11-01

    The purpose of this in-vivo study was to evaluate the effect of a single application of Clinpro XT (3M ESPE, Pymble, New South Wales, Australia), a light-curable fluoride varnish, on enamel demineralization adjacent to orthodontic brackets. Thirty-eight patients (152 teeth) whose orthodontic treatment involved extraction of 4 first premolars were recruited. Two premolars each were assigned to the control group (no treatment) and the experimental group (received fluoride varnish application). The study was designed as a nonrandomized split-mouth study in which diagonally opposite quadrants received the same treatment. After the bonding procedures, a sectional T-loop was ligated into each bracket to serve as a site for plaque retention for enhanced demineralization. Clinpro XT was applied on the buccal surfaces adjacent to the brackets on all teeth in the experimental group only. Teeth in both groups were extracted after 15 days (n = 30), 30 days (n = 30), 45 days (n = 30), 90 days (n = 18), and 120 days (n = 18). Buccolingual sections were then evaluated under polarized light microscopy. After we excluded the dropouts, the mean depth of the demineralized enamel lesions was measured in final sample of 126 teeth. The Mann-Whitney test was used for comparison of the groups. In the control group, the depths of the demineralized enamel lesions increased from 30 to 120 days, whereas in the experimental group no sign of demineralization was noted throughout the observation period except for 3 teeth. Significant differences in the depths of demineralized lesions were found between the study groups. Clinpro XT light-curable fluoride varnish may be a reasonable alternative in the reduction of enamel demineralization around orthodontic brackets, especially in noncompliant and high-risk patients. Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  10. An ab initio/Rice-Ramsperger-Kassel-Marcus study of the hydrogen-abstraction reactions of methyl ethers, H(3)COCH(3-x)(CH(3))(x), x = 0-2, by OH; mechanism and kinetics.

    PubMed

    Zhou, Chong-Wen; Simmie, John M; Curran, Henry J

    2010-07-14

    A theoretical study of the mechanism and kinetics of the H-abstraction reaction from dimethyl (DME), ethylmethyl (EME) and iso-propylmethyl (IPME) ethers by the OH radical has been carried out using the high-level methods CCSD(T)/CBS, G3 and G3MP2BH&H. The computationally less-expensive methods of G3 and G3MP2BH&H yield results for DME within 0.2-0.6 and 0.7-0.9 kcal mol(-1), respectively, of the coupled cluster, CCSD(T), values extrapolated to the basis set limit. So the G3 and G3MP2BH&H methods can be confidently used for the reactions of the higher ethers. A distinction is made between the two different kinds of H-atoms, classified as in/out-of the symmetry plane, and it is found that abstraction from the out-of-plane H-atoms proceeds through a stepwise mechanism involving the formation of a reactant complex in the entrance channel and product complex in the exit channel. The in-plane H-atom abstractions take place through a more direct mechanism and are less competitive. Rate constants of the three reactions have been calculated in the temperature range of 500-3000 K using the Variflex code, based on the weak collision, master equation/microcanonical variational RRKM theory including tunneling corrections. The computed total rate constants (cm(3) mol(-1) s(-1)) have been fitted as follows: k(DME) = 2.74 xT(3.94) exp (1534.2/T), k(EME) = 20.93 xT(3.61) exp (2060.1/T) and k(IPME) = 0.55 xT(3.93) exp (2826.1/T). Expressions of the group rate constants for the three different carbon sites are also provided.

  11. Baseline Demographics, Safety, and Patient Acceptance of an Insertable Cardiac Monitor for Atrial Fibrillation Screening: The REVEAL-AF Study.

    PubMed

    Conti, Sergio; Reiffel, James A; Gersh, Bernard J; Kowey, Peter R; Wachter, Rolf; Halperin, Jonathan L; Kaplon, Rachelle E; Pouliot, Erika; Verma, Atul

    2017-01-01

    Given the high prevalence and risk of stroke associated with atrial fibrillation (AF), detection strategies have important public health implications. The ongoing prospective, single-arm, open-label, multicenter REVEAL AF trial is evaluating the incidence of previously undetected AF using an insertable cardiac monitor (ICM) in patients without prior AF or device implantation, but who could be at risk for AF due to their demographic characteristics, +/- non-specific but compatible symptoms. Enrollment required an elevated AF risk profile defined as CHADS2≥3 or CHADS 2 =2 plus one or more of the following: coronary artery disease, renal impairment, sleep apnea or chronic obstructive pulmonary disease. Exclusions included stroke or transient ischemic attack occurring in the previous year. Of 450 subjects screened, 399 underwent a device insertion attempt, and 395 were included in the final analysis (Reveal XT: n=122; Reveal LINQ: n=273; excluded: n=4). Participants were primarily identified by demographic characteristics and the presence of nonspecific symptoms, but without prior documentation of "overt" AF. The most common symptoms were palpitations (51%), dizziness/lightheadedness/pre-syncope (36%), and shortness of breath (36%). Over 100 subjects were enrolled in each pre-defined CHADS2 subgroup (2, 3 and ≥4). AF risk factors not included in the CHADS2 score were well represented (prevalence≥15%). Procedure and/or device related serious adverse events were low, with the miniaturized Reveal LINQ ICM having a more favorable safety profile than the predicate Reveal XT (all: n=13 [3.3%]; LINQ: n=6 [2.2%]; XT: n=7 [5.7%]). These data demonstrate that REVEAL AF was successful in enrolling its target population, high risk patients were willing to undergo ICM monitoring for AF screening, and ICM use in this group is becoming increasingly safe with advancements in technology. A clinically meaningful incidence of device detected AF in this study will inform clinical decisions regarding ICM use for AF screening in patients at risk.

  12. Neurovirulence of Type 1 Polioviruses Isolated from Sewage in Japan

    PubMed Central

    Horie, Hitoshi; Yoshida, Hiromu; Matsuura, Kumiko; Miyazawa, Miwako; Ota, Yoshihiro; Nakayama, Takashi; Doi, Yutaka; Hashizume, So

    2002-01-01

    Sixteen type 1 poliovirus strains were isolated from a sewage disposal plant located downstream of the Oyabe River in Japan between October 1993 and September 1995. The isolates were intratypically differentiated as vaccine-derived strains. Neutralizing antigenicity analysis with monoclonal antibodies and estimation of neurovirulence by mutant analysis by PCR and restriction enzyme cleavage (MAPREC) were performed for 13 type 1 strains of these isolates. The isolates were classified into three groups. Group I (five strains) had a variant type of antigenicity and neurovirulent phenotype. Group II (four strains) had the vaccine type of antigenicity and neurovirulent phenotype. Group III (four strains) had the vaccine type of antigenicity and an attenuated phenotype. Furthermore, it was demonstrated that the virulent isolates were neutralized by human sera obtained after oral poliomyelitis vaccine (OPV) administration, and the sera of rats immunized with inactivated poliovirus vaccine. Although vaccination was effective against virulent polioviruses, virulent viruses will continue to exist in the environment as long as OPV is in use. PMID:11772619

  13. Microbacterium agarici sp. nov., Microbacterium humi sp. nov. and Microbacterium pseudoresistens sp. nov., isolated from the base of the mushroom Agaricus blazei.

    PubMed

    Young, C-C; Busse, H-J; Langer, S; Chu, Jiunn-Nan; Schumann, P; Arun, A B; Shen, Fo-Ting; Rekha, P D; Kämpfer, P

    2010-04-01

    Three Gram-positive, rod-shaped bacteria (strains CC-SBCK-209( T), CC-12309(T) and CC-5209(T)) were isolated from the stalk of the edible mushroom Agaricus blazei grown in the laboratory. 16S rRNA gene sequence analysis indicated that all three isolates clearly belonged to the genus Microbacterium. Strains CC-SBCK-209( T) and CC-12309(T) were most related closely to the type strain of Microbacterium halotolerans (95.9 and 96.1 % 16S rRNA gene sequence similarity, respectively). These two novel strains shared 97.9 % 16S rRNA gene sequence similarity. Levels of similarity to the type strains of all other recognized Microbacterium species were lower than 95.5 %. The third strain (CC-5209( T)) showed the highest 16S rRNA gene sequence similarity to the type strain of Microbacterium resistens (97.6 %); levels of similarity to the type strains of all other recognized Microbacterium species were lower than 96 %. The quinone systems of strains CC-SBCK-209(T), CC-12309(T) and CC-5209(T) consisted of MK-11/MK-12, MK-11/MK-10 and MK-13 as major compounds, respectively. All three strains contained ornithine in their peptidoglycan. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and an unknown glycolipid. The polyamine pattern consisted of spermidine and spermine as predominant components. Fatty acid profiles (anteiso-C(15 : 0), iso-C(16 : 0) and anteiso-C(17 : 0 ) as major components) supported the affiliation of all three strains to the genus Microbacterium. The results of physiological and biochemical tests and DNA-DNA hybridization experiments allowed the clear phenotypic and genotypic differentiation of strains CC-SBCK-209(T) and CC-12309( T) from M. halotolerans and other closely related Microbacterium species. Strain CC-5209(T) could be differentiated clearly from M. resistens both genotypically and phenotypically. Based on these data, the novel strains are considered to represent three novel species of the genus Microbacterium. The names proposed for these organisms are Microbacterium agarici sp. nov. [type strain CC-SBCK-209( T) (=DSM 21798(T)=CCM 7686(T))], Microbacterium humi sp. nov. [type strain CC-12309(T) (=DSM 21799(T)=CCM 7687(T))] and Microbacterium pseudoresistens sp. nov. [type strain CC-5209(T) (=DSM 22185(T)=CCM 7688(T))].

  14. Identification of Novel Linear Megaplasmids Carrying a ß-Lactamase Gene in Neurotoxigenic Clostridium butyricum Type E Strains

    PubMed Central

    Franciosa, Giovanna; Scalfaro, Concetta; Di Bonito, Paola; Vitale, Marco; Aureli, Paolo

    2011-01-01

    Since the first isolation of type E botulinum toxin-producing Clostridium butyricum from two infant botulism cases in Italy in 1984, this peculiar microorganism has been implicated in different forms of botulism worldwide. By applying particular pulsed-field gel electrophoresis run conditions, we were able to show for the first time that ten neurotoxigenic C. butyricum type E strains originated from Italy and China have linear megaplasmids in their genomes. At least four different megaplasmid sizes were identified among the ten neurotoxigenic C. butyricum type E strains. Each isolate displayed a single sized megaplasmid that was shown to possess a linear structure by ATP-dependent exonuclease digestion. Some of the neurotoxigenic C. butyricum type E strains possessed additional smaller circular plasmids. In order to investigate the genetic content of the newly identified megaplasmids, selected gene probes were designed and used in Southern hybridization experiments. Our results revealed that the type E botulinum neurotoxin gene was chromosome-located in all neurotoxigenic C. butyricum type E strains. Similar results were obtained with the 16S rRNA, the tetracycline tet(P) and the lincomycin resistance protein lmrB gene probes. A specific mobA gene probe only hybridized to the smaller plasmids of the Italian C. butyricum type E strains. Of note, a ß-lactamase gene probe hybridized to the megaplasmids of eight neurotoxigenic C. butyricum type E strains, of which seven from clinical sources and the remaining one from a food implicated in foodborne botulism, whereas this ß-lactam antibiotic resistance gene was absent form the megaplasmids of the two soil strains examined. The widespread occurrence among C. butyricum type E strains associated to human disease of linear megaplasmids harboring an antibiotic resistance gene strongly suggests that the megaplasmids could have played an important role in the emergence of C. butyricum type E as a human pathogen. PMID:21738770

  15. Development of a combined canine distemper virus specific RT-PCR protocol for the differentiation of infected and vaccinated animals (DIVA) and genetic characterization of the hemagglutinin gene of seven Chinese strains demonstrated in dogs.

    PubMed

    Yi, Li; Cheng, Shipeng; Xu, Hongli; Wang, Jianke; Cheng, Yuening; Yang, Shen; Luo, Bin

    2012-01-01

    A combined reverse-transcription polymerase chain reaction (RT-PCR) method was developed for the detection and differentiation of wild-type and vaccine strains of the canine distemper virus (CDV). A pair of primers (P1/P2) was used to detect both CDV wild-type strains and vaccines. Another pair (P3/P4) was used to detect only CDV wild-type strains. A 335bp fragment was amplified from the genomic RNA of the vaccine and wild-type strains. A 555bp fragment was amplified specifically from the genomic RNA of the wild-type strains. No amplification was achieved for the uninfected cells, cells infected with canine parvovirus, canine coronavirus, or canine adenovirus. The combined RT-PCR method detected effectively and differentiated the CDV wild-type and vaccine strains by two separate RT-PCRs. The method can be used for clinical detection and epidemiological surveillance. The phylogenetic analysis of the hemagglutinin gene of the local wild-type CDV strains revealed that the seven local isolates all belonged to the Asia-1 lineage, and were clustered closely with one another at the same location. These results suggested that the CDV genotype Asia-1 is circulating currently in domestic dogs in China. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. A new scheme for strain typing of methicillin-resistant Staphylococcus aureus on the basis of matrix-assisted laser desorption ionization time-of-flight mass spectrometry by using machine learning approach.

    PubMed

    Wang, Hsin-Yao; Lee, Tzong-Yi; Tseng, Yi-Ju; Liu, Tsui-Ping; Huang, Kai-Yao; Chang, Yung-Ta; Chen, Chun-Hsien; Lu, Jang-Jih

    2018-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA), one of the most important clinical pathogens, conducts an increasing number of morbidity and mortality in the world. Rapid and accurate strain typing of bacteria would facilitate epidemiological investigation and infection control in near real time. Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry is a rapid and cost-effective tool for presumptive strain typing. To develop robust method for strain typing based on MALDI-TOF spectrum, machine learning (ML) is a promising algorithm for the construction of predictive model. In this study, a strategy of building templates of specific types was used to facilitate generating predictive models of methicillin-resistant Staphylococcus aureus (MRSA) strain typing through various ML methods. The strain types of the isolates were determined through multilocus sequence typing (MLST). The area under the receiver operating characteristic curve (AUC) and the predictive accuracy of the models were compared. ST5, ST59, and ST239 were the major MLST types, and ST45 was the minor type. For binary classification, the AUC values of various ML methods ranged from 0.76 to 0.99 for ST5, ST59, and ST239 types. In multiclass classification, the predictive accuracy of all generated models was more than 0.83. This study has demonstrated that ML methods can serve as a cost-effective and promising tool that provides preliminary strain typing information about major MRSA lineages on the basis of MALDI-TOF spectra.

  17. Strain driven sequential magnetic transitions in strained GdTiO3 on compressive substrates: a first-principles study.

    PubMed

    Yang, Li-Juan; Weng, Ya-Kui; Zhang, Hui-Min; Dong, Shuai

    2014-11-26

    The compressive strain effect on the magnetic ground state and electronic structure of strained GdTiO3 has been studied using the first-principles method. Unlike the cases of congeneric YTiO3 and LaTiO3, both of which become the A-type antiferromagnetism on the (0 0 1) LaAlO3 substrate despite their contrastive magnetism, the ground state of strained GdTiO3 on the LaAlO3 substrate changes from the original ferromagnetism to a G-type antiferromagnetim, instead of the A-type one although Gd(3+) is between Y(3+) and La(3+). It is only when the in-plane compressive strain is large enough, e.g. on the (0 0 1) YAlO3 substrate, that the ground state finally becomes the A-type. The band structure calculation shows that the compressive strained GdTiO3 remains insulating, although the band gap changes a little in the strained GdTiO3.

  18. Development of a Spoke Type Torque Sensor Using Painting Carbon Nanotube Strain Sensors.

    PubMed

    Kim, Sung Yong; Park, Se Hoon; Choi, Baek Gyu; Kang, In Hyuk; Park, Sang Wook; Shin, Jeong Woo; Kim, Jin Ho; Baek, Woon Kyung; Lim, Kwon Taek; Kim, Young-Ju; Song, Jae-Bok; Kang, Inpil

    2018-03-01

    This study reports a hub-spoke type joint torque sensor involving strain gauges made of multiwalled carbon nanotubes (MWCNT). We developed the novel joint torque sensor for robots by means of MWCNT/epoxy strain sensors (0.8 wt%, gauge factor 2) to overcome the limits of conventional foil strain gauges. Solution mixing process was hired to fabricate a liquid strain sensor that can easily be installed on any complicated surfaces. We painted the MWCNT/epoxy mixing liquid on the hub-spoke type joint torque sensor to form the piezoresistive strain gauges. The painted sensor converted its strain into torque by mean of the installed hub-spoke structure after signal processing. We acquired sufficient torque voltage responses from the painted MWCNT/epoxy strain sensor.

  19. A comparative study of extracellular glucanhydrolase and glucosyltransferase enzyme activities of five different serotypes of oral Streptococcus mutans.

    PubMed

    Felgenhauer, B; Trautner, K

    1982-01-01

    The activities of glucanhydrolase (EC 3.2.1.11) and glucosyltransferase (EC 2.4.1.5) in crude enzyme preparations of 44 strains of Streptococcus mutans of five serotypes were investigated. The strains were grown in a laboratory fermentor for 16 h and the enzymes were isolated by adding solid ammonium sulphate to the culture supernatant, resulting in a 12-fold enrichment of the enzymes. For glucanhydrolase, strains of serotype a showed the lowest total activity (0.768 U, approx. 120 ml), whereas strains of serotype d had an activity 39 times higher (29.9 U). The total activities of strains of serotypes b, c and e were 5.56, 6.30 and 7.06 U, respectively. For glucosyltransferase, strains of type e showed the highest total activity (293 U), whereas differences between strains of the other four types were insignificant (type a: 158 U; type b: 175 U; type c: 191 U; type d: 225 U; approx. 120 ml). A strong correlation was found between the glucanhydrolase activity and the percentage of insoluble glucan synthesized in vitro by the respective strains. This correlation was not substantially changed if the enzyme activities were expressed as specific activities, or as total activities against bacterial weight.

  20. Use of the VNTR typing technique to determine the origin of Mycobacterium tuberculosis strains isolated from Filipino patients in Korea.

    PubMed

    Lee, Jihye; Tupasi, Thelma E; Park, Young Kil

    2014-05-01

    With increasing international interchange of personnel, international monitoring is necessary to decrease tuberculosis incidence in the world. This study aims to develop a new tool to determine origin of Mycobacterium tuberculosis strains isolated from Filipino patients living in Korea. Thirty-two variable number tandem repeat (VNTR) loci were used for discrimination of 50 Filipino M. tuberculosis strains isolated in the Philippines, 317 Korean strains isolated in Korea, and 8 Filipino strains isolated in Korea. We found that the VNTR loci 0580, 0960, 2531, 2687, 2996, 0802, 2461, 2163a, 4052, 0424, 1955, 2074, 2347, 2401, 3171, 3690, 2372, 3232, and 4156 had different mode among copy numbers or exclusively distinct copy number in VNTR typing between Filipino and Korean M. tuberculosis strains. When these differences of the VNTR loci were applied to 8 Filipino M. tuberculosis strains isolated in Korea, 6 of them revealed Filipino type while 2 of them had Korean type. Using the differences of mode or repeated number of VNTR loci were very useful in distinguishing the Filipino strain from Korean strain.

  1. Genotypic and phenotypic characterization of Clostridium perfringens isolates from Darmbrand cases in post-World War II Germany.

    PubMed

    Ma, Menglin; Li, Jihong; McClane, Bruce A

    2012-12-01

    Clostridium perfringens type C strains are the only non-type-A isolates that cause human disease. They are responsible for enteritis necroticans, which was termed Darmbrand when occurring in post-World War II Germany. Darmbrand strains were initially classified as type F because of their exceptional heat resistance but later identified as type C strains. Since only limited information exists regarding Darmbrand strains, this study genetically and phenotypically characterized seven 1940s era Darmbrand-associated strains. Results obtained indicated the following. (i) Five of these Darmbrand isolates belong to type C, carry beta-toxin (cpb) and enterotoxin (cpe) genes on large plasmids, and express both beta-toxin and enterotoxin. The other two isolates are cpe-negative type A. (ii) All seven isolates produce highly heat-resistant spores with D(100) values (the time that a culture must be kept at 100°C to reduce its viability by 90%) of 7 to 40 min. (iii) All of the isolates surveyed produce the same variant small acid-soluble protein 4 (Ssp4) made by type A food poisoning isolates with a chromosomal cpe gene that also produce extremely heat-resistant spores. (iv) The Darmbrand isolates share a genetic background with type A chromosomal-cpe-bearing isolates. Finally, it was shown that both the cpe and cpb genes can be mobilized in Darmbrand isolates. These results suggest that C. perfringens type A and C strains that cause human food-borne illness share a spore heat resistance mechanism that likely favors their survival in temperature-abused food. They also suggest possible evolutionary relationships between Darmbrand strains and type A strains carrying a chromosomal cpe gene.

  2. Comparing in vitro and in vivo virulence phenotypes of Burkholderia pseudomallei type G strains.

    PubMed

    Lewis, Eric R G; Kilgore, Paul B; Mott, Tiffany M; Pradenas, Gonzalo A; Torres, Alfredo G

    2017-01-01

    Burkholderia pseudomallei (Bpm) is a saprophytic rod-shaped gram-negative bacterium and the causative agent of melioidosis. This disease has previously been described as endemic in areas such as northern Australia and Southeast Asia, but, more recently, a better understanding of the epidemiology of melioidosis indicated that the disease is distributed worldwide, including regions of the Americas and Africa. A 16S-23S rDNA internal transcribed spacer (ITS) typing system has been developed for Bpm and has revealed that ITS types C, E, and hybrid CE are mainly associated with Australia and Southeast Asia while type G strains are more associated with cases of melioidosis in the Western Hemisphere. The purpose of the current study was to determine the in vitro and in vivo virulence profiles of the understudied Bpm type G strains Ca2009, Ca2013a, Mx2013, and 724644 and compared such phenotypes to the commonly studied Bpm type C strain K96243. We evaluated virulence by measuring invasion/uptake and survival of these Bpm strains in murine respiratory epithelial LA-4 cells and alveolar macrophage MH-S cells using different multiplicity of infections (MOIs of 1 and 10). We also calculated the lethal dose 50 values (LD50) in BALB/c mice that were inoculated intranasally with either Ca2009, Ca2013a, or Mx2013. Overall, the virulence and lethality phenotypes of Bpm type G strains were similar to the Bpm type C strain K96243. Additional comparative analyses between the Bpm ITS types may lead to a better understanding of the contribution of the ITS type to the epidemiology and ecology of Bpm strains.

  3. Comparing in vitro and in vivo virulence phenotypes of Burkholderia pseudomallei type G strains

    PubMed Central

    Mott, Tiffany M.; Pradenas, Gonzalo A.

    2017-01-01

    Burkholderia pseudomallei (Bpm) is a saprophytic rod-shaped gram-negative bacterium and the causative agent of melioidosis. This disease has previously been described as endemic in areas such as northern Australia and Southeast Asia, but, more recently, a better understanding of the epidemiology of melioidosis indicated that the disease is distributed worldwide, including regions of the Americas and Africa. A 16S-23S rDNA internal transcribed spacer (ITS) typing system has been developed for Bpm and has revealed that ITS types C, E, and hybrid CE are mainly associated with Australia and Southeast Asia while type G strains are more associated with cases of melioidosis in the Western Hemisphere. The purpose of the current study was to determine the in vitro and in vivo virulence profiles of the understudied Bpm type G strains Ca2009, Ca2013a, Mx2013, and 724644 and compared such phenotypes to the commonly studied Bpm type C strain K96243. We evaluated virulence by measuring invasion/uptake and survival of these Bpm strains in murine respiratory epithelial LA-4 cells and alveolar macrophage MH-S cells using different multiplicity of infections (MOIs of 1 and 10). We also calculated the lethal dose 50 values (LD50) in BALB/c mice that were inoculated intranasally with either Ca2009, Ca2013a, or Mx2013. Overall, the virulence and lethality phenotypes of Bpm type G strains were similar to the Bpm type C strain K96243. Additional comparative analyses between the Bpm ITS types may lead to a better understanding of the contribution of the ITS type to the epidemiology and ecology of Bpm strains. PMID:28414823

  4. Effect of strain on electronic and thermoelectric properties of few layers to bulk MoS₂.

    PubMed

    Bhattacharyya, Swastibrata; Pandey, Tribhuwan; Singh, Abhishek K

    2014-11-21

    The sensitive dependence of the electronic and thermoelectric properties of MoS₂ on applied strain opens up a variety of applications in the emerging area of straintronics. Using first-principles-based density functional theory calculations, we show that the band gap of a few layers of MoS₂ can be tuned by applying normal compressive (NC) strain, biaxial compressive (BC) strain, and biaxial tensile (BT) strain. A reversible semiconductor-to-metal transition (S-M transition) is observed under all three types of strain. In the case of NC strain, the threshold strain at which the S-M transition occurs increases when the number of layers increase and becomes maximum for the bulk. On the other hand, the threshold strain for the S-M transition in both BC and BT strains decreases when the number of layers increase. The difference in the mechanisms for the S-M transition is explained for different types of applied strain. Furthermore, the effect of both strain type and the number of layers on the transport properties are also studied using Botzmann transport theory. We optimize the transport properties as a function of the number of layers and the applied strain. 3L- and 2L-MoS₂ emerge as the most efficient thermoelectric materials under NC and BT strain, respectively. The calculated thermopower is large and comparable to some of the best thermoelectric materials. A comparison among the feasibility of these three types of strain is also discussed.

  5. Diversity of Group I and II Clostridium botulinum Strains from France Including Recently Identified Subtypes

    PubMed Central

    Mazuet, Christelle; Legeay, Christine; Sautereau, Jean; Ma, Laurence; Bouchier, Christiane; Bouvet, Philippe; Popoff, Michel R.

    2016-01-01

    In France, human botulism is mainly food-borne intoxication, whereas infant botulism is rare. A total of 99 group I and II Clostridium botulinum strains including 59 type A (12 historical isolates [1947–1961], 43 from France [1986–2013], 3 from other countries, and 1 collection strain), 31 type B (3 historical, 23 recent isolates, 4 from other countries, and 1 collection strain), and 9 type E (5 historical, 3 isolates, and 1 collection strain) were investigated by botulinum locus gene sequencing and multilocus sequence typing analysis. Historical C. botulinum A strains mainly belonged to subtype A1 and sequence type (ST) 1, whereas recent strains exhibited a wide genetic diversity: subtype A1 in orfX or ha locus, A1(B), A1(F), A2, A2b2, A5(B2′) A5(B3′), as well as the recently identified A7 and A8 subtypes, and were distributed into 25 STs. Clostridium botulinum A1(B) was the most frequent subtype from food-borne botulism and food. Group I C. botulinum type B in France were mainly subtype B2 (14 out of 20 historical and recent strains) and were divided into 19 STs. Food-borne botulism resulting from ham consumption during the recent period was due to group II C. botulinum B4. Type E botulism is rare in France, 5 historical and 1 recent strains were subtype E3. A subtype E12 was recently identified from an unusual ham contamination. Clostridium botulinum strains from human botulism in France showed a wide genetic diversity and seems to result not from a single evolutionary lineage but from multiple and independent genetic rearrangements. PMID:27189984

  6. ELECTROPHORETIC MOBILITIES OF ESCHERICHIA COLI 0157:H7 AND WILD-TYPE ESCHERICHIA COLI STRAINS

    EPA Science Inventory

    The electrophoretic mobility (EPM) of a number of human-virulent and "wild-type" Escherichia coli strains in phosphate buffered water was measured. The impact of pH, ionic strength, cation type (valence) and concentration, and bacterial strain on the EPM was investigated. Resul...

  7. Diversity of staphylococcal cassette chromosome mec structures in methicillin-resistant Staphylococcus epidermidis and Staphylococcus haemolyticus strains among outpatients from four countries.

    PubMed

    Ruppé, Etienne; Barbier, François; Mesli, Yasmine; Maiga, Aminata; Cojocaru, Radu; Benkhalfat, Mokhtar; Benchouk, Samia; Hassaine, Hafida; Maiga, Ibrahim; Diallo, Amadou; Koumaré, Abdel Karim; Ouattara, Kalilou; Soumaré, Sambou; Dufourcq, Jean-Baptiste; Nareth, Chhor; Sarthou, Jean-Louis; Andremont, Antoine; Ruimy, Raymond

    2009-02-01

    In staphylococci, methicillin (meticillin) resistance (MR) is mediated by the acquisition of the mecA gene, which is carried on the size and composition variable staphylococcal cassette chromosome mec (SCCmec). MR has been extensively studied in Staphylococcus aureus, but little is known about MR coagulase-negative staphylococci (MR-CoNS). Here, we describe the diversity of SCCmec structures in MR-CoNS from outpatients living in countries with contrasting environments: Algeria, Mali, Moldova, and Cambodia. Their MR-CoNS nasal carriage rates were 29, 17, 11, and 31%, respectively. Ninety-six MR-CoNS strains, comprising 75 (78%) Staphylococcus epidermidis strains, 19 (20%) Staphylococcus haemolyticus strains, 1 (1%) Staphylococcus hominis strain, and 1 (1%) Staphylococcus cohnii strain, were analyzed. Eighteen different SCCmec types were observed, with 28 identified as type IV (29%), 25 as type V (26%), and 1 as type III (1%). Fifteen strains (44%) were untypeable for their SCCmec. Thirty-four percent of MR-CoNS strains contained multiple ccr copies. Type IV and V SCCmec were preferentially associated with S. epidermidis and S. haemolyticus, respectively. MR-CoNS constitute a widespread and highly diversified MR reservoir in the community.

  8. Use of AFLP, plasmid typing and phenotyping in a comparative study to assess genetic diversity of Shigella flexneri strains.

    PubMed Central

    Herrera, S.; Cabrera, R.; Ramirez, M. M.; Usera, M. A.; Echeita, M. A.

    2002-01-01

    Shigella flexneri infections are one of the main causes of acute diarrhoea in Cuba. Twenty strains isolated from sporadic cases in nine different Cuban provinces were characterized. Serotyping, antibiotic-resistance typing, plasmid-typing and AFLP-typing were used to determine their suitability for use in epidemiological studies of S. flexneri. The predominant serotypes were serotype 6 (35%) and serotype 2 (35%). Eleven different plasmid profiles were detected (Diversity Index = 0.92). AFLP-typing discriminated 12 different patterns (DI = 0.95), these patterns were not coincident with plasmid-typing patterns. Both techniques combined distinguished 14 patterns among the 20 studied strains (DI = 0.99). There was no consistent relationship between plasmid-typing and AFLP-typing patterns or antibiotic-resistance typing patterns. Ninety-five percent of S. flexneri strains were multiresistant. PMID:12558326

  9. Effect of strain on thermoelectric properties of SrTiO3: First-principles calculations

    NASA Astrophysics Data System (ADS)

    Zou, Daifeng; Liu, Yunya; Xie, Shuhong; Lin, Jianguo; Li, Jiangyu

    2013-10-01

    The electronic structures of strained SrTiO3 were investigated by using first-principles calculations, and the anisotropic thermoelectric properties of n-type SrTiO3 under biaxial strain were calculated on the base of the semi-classical Boltzmann transport theory. It was theoretically found that the in-plane and out-of-plane power factors of n-type SrTiO3 can be increased under compressive and tensile strains, respectively, and such dependence can be explained by the strain-induced redistribution of electrons. To further optimize the thermoelectric performance of n-type SrTiO3, the maximum power factors and the corresponding optimal n-type doping levels were evaluated.

  10. Typing Discrepancy Between Phenotypic and Molecular Characterization Revealing an Emerging Biovar 9 Variant of Smooth Phage-Resistant B. abortus Strain 8416 in China.

    PubMed

    Kang, Yao-Xia; Li, Xu-Ming; Piao, Dong-Ri; Tian, Guo-Zhong; Jiang, Hai; Jia, En-Hou; Lin, Liang; Cui, Bu-Yun; Chang, Yung-Fu; Guo, Xiao-Kui; Zhu, Yong-Zhang

    2015-01-01

    A newly isolated smooth colony morphology phage-resistant strain 8416 isolated from a 45-year-old cattle farm cleaner with clinical features of brucellosis in China was reported. The most unusual phenotype was its resistance to two Brucella phages Tbilisi and Weybridge, but sensitive to Berkeley 2, a pattern similar to that of Brucella melitensis biovar 1. VITEK 2 biochemical identification system found that both strain 8416 and B. melitensis strains shared positive ILATk, but negative in other B. abortus strains. However, routine biochemical and phenotypic characteristics of strain 8416 were most similar to that of B. abortus biovar 9 except CO2 requirement. In addition, multiple PCR molecular typing assays including AMOS-PCR, B. abortus special PCR (B-ab PCR) and a novel sub-biovar typing PCR, indicated that strain 8416 may belong to either biovar 3b or 9 of B. abortus. Surprisingly, further MLVA typing results showed that strain 8416 was most closely related to B. abortus biovar 3 in the Brucella MLVA database, primarily differing in 4 out of 16 screened loci. Therefore, due to the unusual discrepancy between phenotypic (biochemical reactions and particular phage lysis profile) and molecular typing characteristics, strain 8416 could not be exactly classified to any of the existing B. abortus biovars and might be a new variant of B. abortus biovar 9. The present study also indicates that the present phage typing scheme for Brucella sp. is subject to variation and the routine Brucella biovar typing needs further studies.

  11. Role of Mrx Fimbriae of Xenorhabdus nematophila in Competitive Colonization of the Nematode Host ▿

    PubMed Central

    Snyder, Holly; He, Hongjun; Owen, Heather; Hanna, Chris; Forst, Steven

    2011-01-01

    Xenorhabdus nematophila engages in mutualistic associations with the infective juvenile (IJ) stage of specific entomopathogenic nematodes. Mannose-resistant (Mrx) chaperone-usher-type fimbriae are produced when the bacteria are grown on nutrient broth agar (NB agar). The role of Mrx fimbriae in the colonization of the nematode host has remained unresolved. We show that X. nematophila grown on LB agar produced flagella rather than fimbriae. IJs propagated on X. nematophila grown on LB agar were colonized to the same extent as those propagated on NB agar. Further, progeny IJs were normally colonized by mrx mutant strains that lacked fimbriae both when bacteria were grown on NB agar and when coinjected into the insect host with aposymbiotic nematodes. The mrx strains were not competitively defective for colonization when grown in the presence of wild-type cells on NB agar. In addition, a phenotypic variant strain that lacked fimbriae colonized as well as the wild-type strain. In contrast, the mrx strains displayed a competitive colonization defect in vivo. IJ progeny obtained from insects injected with comixtures of nematodes carrying either the wild-type or the mrx strain were colonized almost exclusively with the wild-type strain. Likewise, when insects were coinjected with aposymbiotic IJs together with a comixture of the wild-type and mrx strains, the resulting IJ progeny were predominantly colonized with the wild-type strain. These results revealed that Mrx fimbriae confer a competitive advantage during colonization in vivo and provide new insights into the role of chaperone-usher fimbriae in the life cycle of X. nematophila. PMID:21856828

  12. 78 FR 12702 - Endangered and Threatened Species; Proposed Rule To List 66 Reef-Building Coral Species; Proposed...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-25

    ... Endangered Species Act (ESA); Extension of Public Comment Period and Notice of Public Hearing AGENCY... RIN 0648-XT12 Endangered and Threatened Species; Proposed Rule To List 66 Reef- Building Coral Species... species as threatened or endangered under the ESA. We concluded that 12 of the petitioned coral species...

  13. History of Canaveral District: 1950 - 1971

    DTIC Science & Technology

    1971-07-01

    world, the Canaveral sites had from the beginning required special precautions to alienate corrosion of exposed items. Special finishes were required...SHA’d rtr,. 111 E.xt 240 PAGE 5 UlI!IIIISTRATIVE Sl/PP(I!T NASA r-- __ .... J___ -. OfF I CZ Ufo ’ ,W,.:m. ’:;ERVI C:.s J. H. DAVl.:l Rrn 109

  14. System Engineering Concept Demonstration, Interface Standards Studies. Volume 4

    DTIC Science & Technology

    1992-12-01

    Xerox’s Palo Alto Research Center (PARC) 25 begat the Xerox Star; Steve Jobs visited PARC, saw the Star, went back to Apple, and begat the Mac. But...Author of Adobe Systems, PostScript Language Program Design, has left Adobe to join Steve Jobs ’ NeXT, Inc. Reid worked for Adobe Systems for four and a

  15. LP1846 Liquid Gun Propellant Dermal Toxicity Study in Male Miniature Hanford Swine.

    DTIC Science & Technology

    1991-11-19

    I Witt et al-- 44 LABORATORY ANIMAL CARE AND USE PORN National Center for Toxicological Research Experiment Number L4&o Title: D e ,mo T ,Xt-? ? Z, F...food/water intake, drug addiction , and stress and shock research that would result in pain approaching the pain tolerance threshold, i.e.. point at

  16. Microcomputer-Based Genetics Office Database System

    PubMed Central

    Cutts, James H.; Mitchell, Joyce A.

    1985-01-01

    A database management system (Genetics Office Automation System, GOAS) has been developed for the Medical Genetics Unit of the University of Missouri. The system, which records patients' visits to the Unit's genetic and prenatal clinics, has been implemented on an IBM PC/XT microcomputer. A description of the system, the reasons for implementation, its databases, and uses are presented.

  17. 75 FR 1723 - Fisheries of the Exclusive Economic Zone Off Alaska; Chiniak Gully Research Area for Vessels...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-13

    ... and Atmospheric Administration (NOAA), Commerce. ACTION: Temporary rule. SUMMARY: NMFS is rescinding the trawl closure in the Chiniak Gully Research Area. This action is necessary to allow vessels using....0910091344-9056-02] RIN 0648-XT71 Fisheries of the Exclusive Economic Zone Off Alaska; Chiniak Gully Research...

  18. Extreme-Teaching-2 (XT [superscript]2): Evaluation of an Innovative Semester-Long Intensive GTA Training Program Based on Microteaching

    ERIC Educational Resources Information Center

    Santandreu Calonge, David; Mark, Kai-Pan; Chiu, P. H. Patrio; Thadani, Dimple R.; Pun, Cecilia F. K.

    2013-01-01

    Microteaching techniques have been used for teacher training since the mid 1960s. Despite its usefulness, as affirmed by pre-service teachers, in-service teachers, and graduate teaching assistants (GTAs), there are numerous criticisms on the shortcomings of microteaching activities. Specifically, it (a) oversimplifies the classroom learning and…

  19. 19 CFR Appendix to Part 102 - Textile and Apparel Manufacturer Identification

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...)—XW NORTHWEST TERRITORIES—XT NOVA SCOTIA—XN NUNAVUT—XV ONTARIO—XO PRINCE EDWARD ISLAND—XP QUEBEC—XQ SASKATCHEWAN—XS YUKON TERRITORY—XY 3. The next group of characters in the MID consists of the first three... name, then only the first three characters from the name are to be used. For example, “Amalgamated...

  20. 19 CFR Appendix to Part 102 - Textile and Apparel Manufacturer Identification

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...)—XW NORTHWEST TERRITORIES—XT NOVA SCOTIA—XN NUNAVUT—XV ONTARIO—XO PRINCE EDWARD ISLAND—XP QUEBEC—XQ SASKATCHEWAN—XS YUKON TERRITORY—XY 3. The next group of characters in the MID consists of the first three... name, then only the first three characters from the name are to be used. For example, “Amalgamated...

  1. 19 CFR Appendix to Part 102 - Textile and Apparel Manufacturer Identification

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...)—XW NORTHWEST TERRITORIES—XT NOVA SCOTIA—XN NUNAVUT—XV ONTARIO—XO PRINCE EDWARD ISLAND—XP QUEBEC—XQ SASKATCHEWAN—XS YUKON TERRITORY—XV 3. The next group of characters in the MID consists of the first three... name, then only the first three characters from the name are to be used. For example, “Amalgamated...

  2. Complete genome sequence of the hippuricase-positive Campylobacter avium type strain LMG 24591

    USDA-ARS?s Scientific Manuscript database

    Campylobacter avium is a hippurate-positive, thermotolerant campylobacter that has been isolated from poultry. Here we present the genome sequences of two C. avium strains isolated from broiler chickens: strains LMG 24591T (complete genome) and LMG 24592 (draft genome). The C. avium type strain geno...

  3. Kribbella albertanoniae sp. nov., isolated from a Roman catacomb, and emended description of the genus Kribbella.

    PubMed

    Everest, Gareth J; Curtis, Sarah M; De Leo, Filomena; Urzì, Clara; Meyers, Paul R

    2013-10-01

    A novel actinobacterium, strain BC640(T), was isolated from a biofilm sample collected in 2009 in the Saint Callistus Roman catacombs. Analysis of the 16S rRNA gene sequence showed that the strain belonged to the genus Kribbella. Phylogenetic analysis using the 16S rRNA gene and concatenated gyrB, rpoB, relA, recA and atpD gene sequences showed that strain BC640(T) was most closely related to the type strains of Kribbella yunnanensis and Kribbella sandramycini. Based on gyrB genetic distance analysis, strain BC640(T) was shown to be distinct from all Kribbella type strains. DNA-DNA hybridization experiments confirmed that strain BC640(T) represents a genomic species distinct from its closest phylogenetic relatives, K. yunnanensis DSM 15499(T) (53.5±7.8 % DNA relatedness) and K. sandramycini DSM 15626(T) (33.5±5.0 %). Physiological comparisons further showed that strain BC640(T) is phenotypically distinct from the type strains of K. yunnanensis and K. sandramycini. Strain BC640(T) ( = DSM 26744(T) = NRRL B-24917(T)) is thus presented as the type strain of a novel species, for which the name Kribbella albertanoniae sp. nov. is proposed.

  4. Multilocus sequence typing of Chlamydia trachomatis among men who have sex with men reveals cocirculating strains not associated with specific subpopulations.

    PubMed

    Bom, Reinier J M; Matser, Amy; Bruisten, Sylvia M; van Rooijen, Martijn S; Heijman, Titia; Morré, Servaas A; de Vries, Henry J C; Schim van der Loeff, Maarten F

    2013-09-01

    Previous studies identified specific Chlamydia trachomatis strains circulating among men who have sex with men (MSM). This study investigates whether distinct C. trachomatis strains circulate among subpopulations within the MSM community. Participants were recruited at the sexually transmitted infection clinic of the Public Health Service of Amsterdam from 2008 to 2009. C. trachomatis samples were typed using multilocus sequence typing. Epidemiological and clinical data were derived from questionnaires and patient records. Typing of 277 samples from 260 MSM identified distinct C. trachomatis strains circulating concurrently over time. Men with lymphogranuloma venereum (LGV)-inducing strains were more likely to be infected with human immunodeficiency virus, more often had a history of STI, and had a higher frequency of risky sexual behavior. No such associations were found for non-LGV-inducing strains. MSM infected with heterosexual-associated strains were often younger (P = .04) and more often reported sex with women (P = .03), compared with men infected with MSM-associated strains. With the exception of LGV-inducing strains, no evidence was found that different C. trachomatis strains circulated in distinct subpopulations of MSM. This indicates that no separate transmission networks for C. trachomatis among MSM existed. However, younger MSM and bisexuals were more often infected with heterosexual-associated C. trachomatis strains.

  5. Molybdenum cofactor in chlorate-resistant and nitrate reductase-deficient insertion mutants of Escherichia coli.

    PubMed Central

    Miller, J B; Amy, N K

    1983-01-01

    We examined molybdenum cofactor activity in chlorate-resistant (chl) and nitrate reductase-deficient (nar) insertion mutants and wild-type strains of Escherichia coli K-12. The bacterial molybdenum cofactor was assayed by its ability to restore activity to the cofactor-deficient nitrate reductase found in the nit-1 strain of Neurospora crassa. In the wild-type E. coli strains, molybdenum cofactor was synthesized constitutively and found in both cytoplasmic and membrane fractions. Cofactor was found in two forms: the demolybdo form required additional molybdate in the assay mix for detection, whereas the molybdenum-containing form was active without additional molybdate. The chlA and chlE mutants had no detectable cofactor. The chlB and the narG, narI, narK, and narL (previously designated chlC) strains had cofactor levels similar to those of the wild-type strains, except the chlB strains had two to threefold more membrane-bound cofactor. Cofactor levels in the chlD and chlG strains were sensitive to molybdate. When grown in 1 microM molybdate, the chlD strains had only 15 to 20% of the wild-type levels of the demolybdo and molybdenum-containing forms of the cofactor. In contrast, the chlG strains had near wild-type levels of demolybdo cofactor when grown in 1 microM molybdate, but none of the molybdenum-containing form of the cofactor. Near wild-type levels of both forms of the cofactor were restored to the chlD and chlG strains by growth in 1 mM molybdate. PMID:6307982

  6. ITS1/5.8S/ITS2, a Good Marker for Initial Classification of Shiitake Culinary-Medicinal Lentinus edodes (Agaricomycetes) Strains in China.

    PubMed

    Song, Xiao-Xia; Zhao, Yan; Song, Chun-Yan; Li, Chuan-Hua; Song, Ying; Chen, Ming-Jie; Bao, Da-Peng; Tan, Qi

    2018-01-01

    China is home to rich wild and cultivated strains of Lentinus edodes, an important edible and medicinal mushroom. Artificial selection of L. edodes has a long history, and the widely cultivated strains belong to populations different from those of most wild strains. Internal transcribed spacer (ITS) regions have been used as good markers to identify L. edodes populations. But because ITS regions exhibit incomplete concerted evolution, the use of an ITS to identify L. edodes populations has been questioned. The objective of this study was to determine whether the ITS region is suitable for identifying L. edodes populations and which populations the widely cultivated strains and the most wild strains belong to by investigating intraindividual and differential ITS polymorphisms between 44 cultivars and 44 wild strains of L. edodes in China. Intraindividual ITS polymorphism is common in L. edodes strains, and most strains possessed 2 different ITS sequences, which came from their heterokaryons. The genetic polymorphisms of ITS1, 5.8S, and ITS2 in L. edodes strains are distinct. All strains were divided into one 5.8S type (5.8S-A), 2 ITS1 types (ITS1-A and ITS1-B), and 2 ITS2 types (ITS2-A and ITS2-B), which were subdivided into 2 branches (ITS2-A1 and ITS2-A2; ITS2-B1 and ITS2-B2). ITS1/5.8S/ITS2 could be used as a good marker in preliminary classification of L. edodes strains in China. It not only exhibited classified information of ITS1, 5.8S, and ITS2 for each strain at the same time, it also indicated whether the strain was heterozygous. The 44 cultivated strains were mainly the A/A/A1 type, and the 44 wild strains were mainly the A/A/A2 and other mixed types.

  7. Acinetobacter lactucae sp. nov., isolated from iceberg lettuce (Asteraceae: Lactuca sativa).

    PubMed

    Rooney, Alejandro P; Dunlap, Christopher A; Flor-Weiler, Lina B

    2016-09-01

    Strain NRRL B-41902T and three closely related strains were isolated from iceberg lettuce. The strain was found to consist of strictly aerobic, Gram-stain-negative rods that formed cocci in late stationary phase. 16S rRNA gene sequence analysis showed that strain NRRL B-41902T was most closely related to species within the genera Acinetobacter, and that a grouping of it and the three other closely related strains was most closely related to the type strain of Acinetobacter pittii, which was also confirmed through a phylogenomic analysis. Moreover, in silico DNA-DNA hybridization analysis revealed a substantial amount of genomic divergence (39.1 %) between strain NRRL B-41902T and the type strain of A. pittii, which is expected if the strains represent distinct species. Further phenotypic analysis revealed that strain NRRL B-41902T was able to utilize a combination of l-serine, citraconic acid and citramalic acid, which differentiated it from other, closely related Acinetobacter species. Therefore, strain NRRL B-41902T (=CCUG 68785T) is proposed as the type strain of a novel species, Acinetobacter lactucae sp. nov.

  8. CodY Promotes Sporulation and Enterotoxin Production by Clostridium perfringens Type A Strain SM101.

    PubMed

    Li, Jihong; Freedman, John C; Evans, Daniel R; McClane, Bruce A

    2017-03-01

    Clostridium perfringens type D strains cause enterotoxemia and enteritis in livestock via epsilon toxin production. In type D strain CN3718, CodY was previously shown to increase the level of epsilon toxin production and repress sporulation. C. perfringens type A strains producing C. perfringens enterotoxin (CPE) cause human food poisoning and antibiotic-associated diarrhea. Sporulation is critical for C. perfringens type A food poisoning since spores contribute to transmission and resistance in the harsh food environment and sporulation is essential for CPE production. Therefore, the current study asked whether CodY also regulates sporulation and CPE production in SM101, a derivative of C. perfringens type A food-poisoning strain NCTC8798. An isogenic codY -null mutant of SM101 showed decreased levels of spore formation, along with lower levels of CPE production. A complemented strain recovered wild-type levels of both sporulation and CPE production. When this result was coupled with the earlier results obtained with CN3718, it became apparent that CodY regulation of sporulation varies among different C. perfringens strains. Results from quantitative reverse transcriptase PCR analysis clearly demonstrated that, during sporulation, codY transcript levels remained high in SM101 but rapidly declined in CN3718. In addition, abrB gene expression patterns varied significantly between codY -null mutants of SM101 and CN3718. Compared to the levels in their wild-type parents, the level of abrB gene expression decreased in the CN3718 codY -null mutant strain but significantly increased in the SM101 codY -null mutant strain, demonstrating CodY-dependent regulation differences in abrB expression between these two strains. This difference appears to be important since overexpression of the abrB gene in SM101 reduced the levels of sporulation and enterotoxin production, supporting the involvement of AbrB repression in regulating C. perfringens sporulation. Copyright © 2017 American Society for Microbiology.

  9. CodY Promotes Sporulation and Enterotoxin Production by Clostridium perfringens Type A Strain SM101

    PubMed Central

    Li, Jihong; Freedman, John C.; Evans, Daniel R.

    2017-01-01

    ABSTRACT Clostridium perfringens type D strains cause enterotoxemia and enteritis in livestock via epsilon toxin production. In type D strain CN3718, CodY was previously shown to increase the level of epsilon toxin production and repress sporulation. C. perfringens type A strains producing C. perfringens enterotoxin (CPE) cause human food poisoning and antibiotic-associated diarrhea. Sporulation is critical for C. perfringens type A food poisoning since spores contribute to transmission and resistance in the harsh food environment and sporulation is essential for CPE production. Therefore, the current study asked whether CodY also regulates sporulation and CPE production in SM101, a derivative of C. perfringens type A food-poisoning strain NCTC8798. An isogenic codY-null mutant of SM101 showed decreased levels of spore formation, along with lower levels of CPE production. A complemented strain recovered wild-type levels of both sporulation and CPE production. When this result was coupled with the earlier results obtained with CN3718, it became apparent that CodY regulation of sporulation varies among different C. perfringens strains. Results from quantitative reverse transcriptase PCR analysis clearly demonstrated that, during sporulation, codY transcript levels remained high in SM101 but rapidly declined in CN3718. In addition, abrB gene expression patterns varied significantly between codY-null mutants of SM101 and CN3718. Compared to the levels in their wild-type parents, the level of abrB gene expression decreased in the CN3718 codY-null mutant strain but significantly increased in the SM101 codY-null mutant strain, demonstrating CodY-dependent regulation differences in abrB expression between these two strains. This difference appears to be important since overexpression of the abrB gene in SM101 reduced the levels of sporulation and enterotoxin production, supporting the involvement of AbrB repression in regulating C. perfringens sporulation. PMID:28052992

  10. Yamadazyma kitorensis f.a., sp. nov. and Zygoascus biomembranicola f.a., sp. nov., novel yeasts from the stone chamber interior of the Kitora tumulus, and five novel combinations in Yamadazyma and Zygoascus for species of Candida.

    PubMed

    Nagatsuka, Yuka; Ninomiya, Shinya; Kiyuna, Tomohiko; Kigawa, Rika; Sano, Chie; Sugiyama, Junta

    2016-04-01

    Analysis of D1/D2 large-subunit (LSU) rRNA gene sequences predicted that 17 yeast isolates, mainly from viscous gels (biofilms) taken from the stone chamber interior of the Kitora tumulus in Nara, Japan, were placed in the Yamadazyma and Zygoascus clades. Polyphasic characterization, including morphological, physiological and chemotaxonomic characteristics, multigene sequence divergence and DNA-DNA hybridization, strongly suggested the assignment of one novel species to each of the clades; these are Yamadazyma kitorensis f.a., sp. nov., with the type strain JCM 31005T (ex-type CBS 14158T=isolate K8617-6-8T), and Zygoascus biomembranicola f.a., sp. nov., with the type strain JCM 31007T (ex-type CBS 14157T=isolate K61208-2-11T). Furthermore, the transfer of five known species of the genus Candida as novel combinations to the genera Yamadazyma and Zygoascus is proposed; these are Yamadazyma olivae f.a., comb. nov. (type strain CBS 11171T=ATCC MYA-4568T), Yamadazyma tumulicola f.a., comb. nov. (type strain JCM 15403T=ex-type CBS 10917T=isolate T6517-9-5T), Yamadazyma takamatsuzukensis f.a., comb. nov. (type strain JCM 15410T=CBS 10916T = isolate T4922-1-1T), Zygoascus polysorbophila f.a., comb. nov. (type strain NRRL Y-27161T=CBS 7317T) and Zygoascus bituminiphila f.a., comb. nov. (type strain CBS 8813T=MUCL 41424T).

  11. Application of physico-chemical typing methods for the epidemiological analysis of Salmonella enteritidis strains of phage type 25/17.

    PubMed Central

    Seltmann, G.; Voigt, W.; Beer, W.

    1994-01-01

    Eighty-nine Salmonella enteritidis phage type 25/17 strains isolated from a localized outbreak in the German state Nordrhein-Westfalen (outbreak NWI) could not be further differentiated by biochemotyping and plasmid pattern analysis. They were submitted to a complex typing system consisting of modern physico-chemical analytical procedures. In lipopolysaccharide pattern analysis the strains proved to be homogeneous. In multilocus enzyme electrophoresis, outer membrane and whole cell protein pattern (WCPP) analysis, and Fourier-transform infrared (FT-IR) spectroscopy (increasing extent of differentiation in the given order) strains deviating from each basal pattern were found. The extent of correspondence in these deviations was satisfactory. Forty-six strains of the same sero- and phage type, however, obtained from different outbreaks, were additionally typed. The results obtained with them indicate that the data of the first group were not restricted to strains from outbreak NWI, but of general validity. It was found that both WCPP and FT-IR represent valuable methods for the sub-grouping of bacteria. Images Fig. 1 Fig. 2 Fig. 3 PMID:7995351

  12. Phenotypic, Genotypic, and Antimicrobial Characteristics of Streptococcus halichoeri Isolates from Humans, Proposal To Rename Streptococcus halichoeri as Streptococcus halichoeri subsp. halichoeri, and Description of Streptococcus halichoeri subsp. hominis subsp. nov., a Bacterium Associated with Human Clinical Infections.

    PubMed

    Shewmaker, P L; Whitney, A M; Humrighouse, B W

    2016-03-01

    Phenotypic, genotypic, and antimicrobial characteristics of six phenotypically distinct human clinical isolates that most closely resembled the type strain of Streptococcus halichoeri isolated from a seal are presented. Sequencing of the 16S rRNA, rpoB, sodA, and recN genes; comparative whole-genome analysis; conventional biochemical and Rapid ID 32 Strep identification methods; and antimicrobial susceptibility testing were performed on the human isolates, the type strain of S. halichoeri, and type strains of closely related species. The six human clinical isolates were biochemically indistinguishable from each other and showed 100% 16S rRNA, rpoB, sodA, and recN gene sequence similarity. Comparative 16S rRNA gene sequencing analysis revealed 98.6% similarity to S. halichoeri CCUG 48324(T), 97.9% similarity to S. canis ATCC 43496(T), and 97.8% similarity to S. ictaluri ATCC BAA-1300(T). A 3,530-bp fragment of the rpoB gene was 98.8% similar to the S. halichoeri type strain, 84.6% to the S. canis type strain, and 83.8% to the S. ictaluri type strain. The S. halichoeri type strain and the human clinical isolates were susceptible to the antimicrobials tested based on CLSI guidelines for Streptococcus species viridans group with the exception of tetracycline and erythromycin. The human isolates were phenotypically distinct from the type strain isolated from a seal; comparative whole-genome sequence analysis confirmed that the human isolates were S. halichoeri. On the basis of these results, a novel subspecies, Streptococcus halichoeri subsp. hominis, is proposed for the human isolates and Streptococcus halichoeri subsp. halichoeri is proposed for the gray seal isolates. The type strain of the novel subspecies is SS1844(T) = CCUG 67100(T) = LMG 28801(T). Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  13. Classification of avian haemolytic Actinobacillus-like organisms (Bisgaard taxon 26) associated with anseriforme birds as Actinobacillus anseriformium sp. nov.

    PubMed

    Bisgaard, M; Christensen, H

    2012-02-01

    Avian haemolytic Actinobacillus-like organisms have tentatively been named Bisgaard taxon 26. Phenotypic information has been published on 65 strains of this taxon. In the current study, 31 isolates were selected for genotypic characterization. Thirty strains had the same rpoB sequence and only one strain diverged in 1 nt. The highest rpoB similarity to members of other taxa was 89.7 % to the type strain of Actinobacillus equuli subsp. haemolyticus and the similarity to the type strain of the type species, Actinobacillus lignieresii, was 88.2 %. The lowest 16S rRNA gene sequence similarity between strains of the group was determined in previous investigations to be 99.6 % and the highest similarities of 96.4 and 96.2 % outside the group were obtained to the reference strain of Actinobacillus genomospecies 2 and to the type strain of A. equuli subsp. equuli, respectively; 95.8-95.3 % similarity was obtained with the type strain of A. lignieresii. recN gene sequence similarities within the group were from 99.5 % (strains F66(T) and F64) to 99.8 % (strains F66(T) and F67) corresponding to genome similarities of 93.9-94.6 %, which are near the upper limit for species compared with other members of the Pasteurellaceae. The highest recN similarity outside the group (83.4 %) was observed to the type strain of Actinobacillus capsulatus, whereas the similarity to the type strain of A. lignieresii was 80.9 %, corresponding to genome similarities of 57.7 and 52.0 %, respectively. All isolates meet the phenotypic characters outlined for Actinobacillus (urease-, phosphatase- and porphyrin-positive, indole-negative, acid production from fructose, sucrose, maltose and dextrin). β-Haemolysis of bovine blood is observed and isolates may demonstrate in vitro satellitic growth, referred to as V-factor or NAD requirement. Isolates have been obtained from the upper respiratory tract of web-footed birds in which they may cause sinusitis, conjunctivitis and septicaemia. Based on the characterization reported, it is proposed that the isolates belong to a novel species, Actinobacillus anseriformium sp. nov., which includes taxon 26 and a V-factor-dependent strain. The major fatty acids of the type strain are C(16 : 1)ω7c, C(14 : 0), C(16 : 0) and C(14 : 0) 3-OH and/or iso-C(16 : 1) I, corresponding to the profile observed for the type strain of A. lignieresii. Five to 12 characters separate A. anseriformium from other taxa of Actinobacillus, with Actinobacillus ureae being most closely related; A. anseriformium can be differentiated from A. ureae based on haemolysis, β-glucosidase, and production of acid from (-)-D-sorbitol, trehalose and glycosides. The type strain of A. anseriformium is F66(T) ( = CCUG 60324(T) = CCM 7846(T)), which was isolated from conjunctivitis in a White Pekin duck.

  14. Strain driven sequential magnetic transitions in strained GdTiO3 on compressive substrates: a first-principles study

    NASA Astrophysics Data System (ADS)

    Yang, Li-Juan; Weng, Ya-Kui; Zhang, Hui-Min; Dong, Shuai

    2014-11-01

    The compressive strain effect on the magnetic ground state and electronic structure of strained GdTiO3 has been studied using the first-principles method. Unlike the cases of congeneric YTiO3 and LaTiO3, both of which become the A-type antiferromagnetism on the (0 0 1) LaAlO3 substrate despite their contrastive magnetism, the ground state of strained GdTiO3 on the LaAlO3 substrate changes from the original ferromagnetism to a G-type antiferromagnetim, instead of the A-type one although Gd3+ is between Y3+ and La3+. It is only when the in-plane compressive strain is large enough, e.g. on the (0 0 1) YAlO3 substrate, that the ground state finally becomes the A-type. The band structure calculation shows that the compressive strained GdTiO3 remains insulating, although the band gap changes a little in the strained GdTiO3.

  15. Genomic diversity among Corynebacterium jeikeium strains and comparison with biochemical characteristics and antimicrobial susceptibilities.

    PubMed Central

    Riegel, P; de Briel, D; Prévost, G; Jehl, F; Monteil, H

    1994-01-01

    Levels of DNA relatedness were determined by performing DNA-DNA hybridization experiments (S1 nuclease procedure) with 13 human isolates exhibiting various antimicrobial susceptibility patterns which had been identified as Corynebacterium jeikeium by classical tests and the API Coryne system and with reference strains of C. jeikeium and related taxa. Twelve of 13 isolates which formed three genomic groups showed between 22 and 75% relatedness with the type strain of C. jeikeium. One of these genomic groups included all the strains resistant to penicillin and gentamicin and is genomically related to the C. jeikeium type strain at the species level. In addition, the reference strain of "Corynebacterium genitalium" biotype II was found to belong to this genospecies and therefore can be considered as a synonym of C. jeikeium. In contrast, one isolate and the reference strains of "Corynebacterium pseudogenitalium" biotypes C-3 and C-4 which were assigned to C. jeikeium by the API Coryne system were less than 10% related to the C. jeikeium type strain. These nongenomically related strains can be differentiated from the jeikeium-related strains on the basis of positive acidification from fructose and growth under anaerobic conditions. Furthermore, these strains exhibited full susceptibility to penicillin whereas the strains related to the C. jeikeium type strain are resistant to or only moderately susceptible to penicillin. No genomic relationship was found between C. jeikeium-related strains and other lipophilic coryneforms, identified as Corynebacterium accolens or Corynebacterium group G or F. Our study demonstrates the necessity to perform the fructose fermentation test or respiratory-type test for the correct identification of lipophilic coryneforms as C. jeikeium. Although these strains show genomic diversity at the species level, in a practical aspect, biochemical properties as well as antimicrobial susceptibility may allow the classification of such isolates in this single taxon. PMID:7989533

  16. Genomic diversity among Corynebacterium jeikeium strains and comparison with biochemical characteristics and antimicrobial susceptibilities.

    PubMed

    Riegel, P; de Briel, D; Prévost, G; Jehl, F; Monteil, H

    1994-08-01

    Levels of DNA relatedness were determined by performing DNA-DNA hybridization experiments (S1 nuclease procedure) with 13 human isolates exhibiting various antimicrobial susceptibility patterns which had been identified as Corynebacterium jeikeium by classical tests and the API Coryne system and with reference strains of C. jeikeium and related taxa. Twelve of 13 isolates which formed three genomic groups showed between 22 and 75% relatedness with the type strain of C. jeikeium. One of these genomic groups included all the strains resistant to penicillin and gentamicin and is genomically related to the C. jeikeium type strain at the species level. In addition, the reference strain of "Corynebacterium genitalium" biotype II was found to belong to this genospecies and therefore can be considered as a synonym of C. jeikeium. In contrast, one isolate and the reference strains of "Corynebacterium pseudogenitalium" biotypes C-3 and C-4 which were assigned to C. jeikeium by the API Coryne system were less than 10% related to the C. jeikeium type strain. These nongenomically related strains can be differentiated from the jeikeium-related strains on the basis of positive acidification from fructose and growth under anaerobic conditions. Furthermore, these strains exhibited full susceptibility to penicillin whereas the strains related to the C. jeikeium type strain are resistant to or only moderately susceptible to penicillin. No genomic relationship was found between C. jeikeium-related strains and other lipophilic coryneforms, identified as Corynebacterium accolens or Corynebacterium group G or F. Our study demonstrates the necessity to perform the fructose fermentation test or respiratory-type test for the correct identification of lipophilic coryneforms as C. jeikeium. Although these strains show genomic diversity at the species level, in a practical aspect, biochemical properties as well as antimicrobial susceptibility may allow the classification of such isolates in this single taxon.

  17. Peri-Implant Strain in an In Vitro Model.

    PubMed

    Hussaini, Souheil; Vaidyanathan, Tritala K; Wadkar, Abhinav P; Quran, Firas A Al; Ehrenberg, David; Weiner, Saul

    2015-10-01

    An in vitro experimental model was designed and tested to determine the influence that peri-implant strain may have on the overall crestal bone. Strain gages were attached to polymethylmethacrylate (PMMA) models containing a screw-type root form implant at sites 1 mm from the resin-implant interface. Three different types of crown superstructures (cemented, 1-screw [UCLA] and 2-screw abutment types) were tested. Loading (1 Hz, 200 N load) was performed using a MTS Mechanical Test System. The strain gage data were stored and organized in a computer for statistical treatment. Strains for all abutment types did not exceed the physiological range for modeling and remodeling of cancellous bone, 200-2500 με (microstrain). For approximately one-quarter of the trials, the strain values were less than 200 με the zone for bone atrophy. The mean microstrain obtained was 517.7 με. In conclusion, the peri-implant strain in this in vitro model did not exceed the physiologic range of bone remodeling under axial occlusal loading.

  18. Difference in Degradation Patterns on Inulin-type Fructans among Strains of Lactobacillus delbrueckii and Lactobacillus paracasei.

    PubMed

    Tsujikawa, Yuji; Nomoto, Ryohei; Osawa, Ro

    2013-01-01

    Lactobacillus delbrueckii strains were assessed for their degradation patterns of various carbohydrates with specific reference to inulin-type fructans in comparison with those of Lactobacillus paracasei strains. Firstly, growth curves on glucose, fructose, sucrose and inulin-type fructans with increasing degrees of fructose polymerization (i.e., 1-kestose, fructo-oligosaccharides and inulin) of the strains were compared. L. paracasei DSM 20020 grew well on all these sugars, while the growth rates of the 4 L. delbrueckii strains were markedly higher on the fructans with a greater degree of polymerization than on fructose and sucrose. Secondly, sugar compositions of spent cultures of the strains of L. delbrueckii and L. paracasei grown in mMRS containing either the fructans or inulin were determined by thin layer chromatography, in which the spent cultures of L. paracasei DSM 20020 showed spots of short fructose and sucrose fractions, whereas those of the L. delbrueckii strains did not show such spots at all. These results suggest that, unlike the L. paracasei strains, the L. delbrueckii strains do not degrade the inulin-type fructans extracellularly, but transport the fructans capable of greater polymerization preferentially into their cells to be degraded intracellularly for their growth.

  19. Molecular characterization of enteroviruses including a new type EV-C99 isolated from Xinjiang students in Shandong, China in 2011.

    PubMed

    Tao, Zexin; Yuan, Qun; Lin, Xiaojuan; Wang, Suting; Liu, Yao; Ji, Feng; Xiong, Ping; Cui, Ning; Song, Lizhi; Wang, Mei; Xu, Aiqiang

    2014-10-09

    The last case of infection with wild-type poliovirus indigenous to China was reported in 1994. In 2011, a poliomyelitis outbreak caused by imported wide-type poliovirus occurred in Xinjiang Uighur Autonomous Region. Here, we report the results of enterovirus (EV) isolation from Xinjiang students that returned to school in Shandong after summer vacation during this outbreak. Stool specimens from 376 students were collected and 10 EV strains were isolated including 4 polioviruses (All Sabin strains), 1 coxsackievirus (CV) A13, 3 CVA17 and 2 EV-C99. VP1 sequence analysis revealed these CVA13, CVA17 and EV-C99 strains had 71.3-81.8%, 76.5-84.6% and 74.2-82.9% nucleotide similarity with strains from other countries within a serotype, respectively. EV-C99 strains had 82.7-92.8% VP1 similarity with two previously reported Xinjiang strains. Complete genome analysis on EV-C99 strains revealed intra-serotypic genetic recombination events. These findings reflect great genetic divergence between Chinese strains and strains from other countries of the three types, and provide valuable information on monitoring EV transmission over long distance.

  20. Difference in Degradation Patterns on Inulin-type Fructans among Strains of Lactobacillus delbrueckii and Lactobacillus paracasei

    PubMed Central

    TSUJIKAWA, Yuji; NOMOTO, Ryohei; OSAWA, Ro

    2013-01-01

    Lactobacillus delbrueckii strains were assessed for their degradation patterns of various carbohydrates with specific reference to inulin-type fructans in comparison with those of Lactobacillus paracasei strains. Firstly, growth curves on glucose, fructose, sucrose and inulin-type fructans with increasing degrees of fructose polymerization (i.e., 1-kestose, fructo-oligosaccharides and inulin) of the strains were compared. L. paracasei DSM 20020 grew well on all these sugars, while the growth rates of the 4 L. delbrueckii strains were markedly higher on the fructans with a greater degree of polymerization than on fructose and sucrose. Secondly, sugar compositions of spent cultures of the strains of L. delbrueckii and L. paracasei grown in mMRS containing either the fructans or inulin were determined by thin layer chromatography, in which the spent cultures of L. paracasei DSM 20020 showed spots of short fructose and sucrose fractions, whereas those of the L. delbrueckii strains did not show such spots at all. These results suggest that, unlike the L. paracasei strains, the L. delbrueckii strains do not degrade the inulin-type fructans extracellularly, but transport the fructans capable of greater polymerization preferentially into their cells to be degraded intracellularly for their growth. PMID:24936375

  1. Comparison and Evaluation of the Molecular Typing Methods for Toxigenic Vibrio cholerae in Southwest China.

    PubMed

    Liao, Feng; Mo, Zhishuo; Chen, Meiling; Pang, Bo; Fu, Xiaoqing; Xu, Wen; Jing, Huaiqi; Kan, Biao; Gu, Wenpeng

    2018-01-01

    Vibrio cholerae O1 strains taken from the repository of Yunnan province, southwest China, were abundant and special. We selected 70 typical toxigenic V. cholerae (69 O1 and one O139 serogroup strains) isolated from Yunnan province, performed the pulsed field gel electrophoresis (PFGE), multilocus sequence typing (MLST), and MLST of virulence gene (V-MLST) methods, and evaluated the resolution abilities for typing methods. The ctxB subunit sequence analysis for all strains have shown that cholera between 1986 and 1995 was associated with mixed infections with El Tor and El Tor variants, while infections after 1996 were all caused by El Tor variant strains. Seventy V. cholerae obtained 50 PFGE patterns, with a high resolution. The strains could be divided into three groups with predominance of strains isolated during 1980s, 1990s, and 2000s, respectively, showing a good consistency with the epidemiological investigation. We also evaluated two MLST method for V. cholerae , one was used seven housekeeping genes ( adk , gyrB , metE , pntA , mdh , purM , and pyrC ), and all the isolates belonged to ST69; another was used nine housekeeping genes ( cat , chi , dnaE , gyrB , lap , pgm , recA , rstA , and gmd ). A total of seven sequence types (STs) were found by using this method for all the strains; among them, rstA gene had five alleles, recA and gmd have two alleles, and others had only one allele. The virulence gene sequence typing method ( ctxAB , tcpA , and toxR ) showed that 70 strains were divided into nine STs; among them, tcpA gene had six alleles, toxR had five alleles, while ctxAB was identical for all the strains. The latter two sequences based typing methods also had consistency with epidemiology of the strains. PFGE had a higher resolution ability compared with the sequence based typing method, and MLST used seven housekeeping genes showed the lower resolution power than nine housekeeping genes and virulence genes methods. These two sequence typing methods could distinguish some epidemiological special strains in local area.

  2. Three novel species of d-xylose-assimilating yeasts, Barnettozyma xylosiphila sp. nov., Barnettozyma xylosica sp. nov. and Wickerhamomyces xylosivorus f.a., sp. nov.

    PubMed

    Kobayashi, Ryuichi; Kanti, Atit; Kawasaki, Hiroko

    2017-10-01

    This study describes three novel xylose-assimilating yeasts, which were isolated from decayed wood collected from Bung Hatta Botanical Garden in West Sumatra and Cibodas Botanic Garden in West Java, or from litter from Eka Karya Bali Botanic Garden in Bali, Indonesia. Phylogenetic analysis was performed based on the sequences of the D1/D2 domains of the large ribosomal subunit (LSU), the small ribosomal subunit (SSU), the internal transcribed spacer (ITS) and elongation factor-1α (EF-1α), and the three strains were found to represent three novel species belonging to genera Barnettozyma or Wickerhamomyces. The morphological, biochemical and physiological characteristics indicated that the strains were distinct from other closely related species. Strains 13Y206 T and 14Y196 T belonging to the Barnettozyma clade are described as the type strains of Barnettozyma xylosiphila sp. nov. (type strain 13Y206 T =NBRC 110202 T =InaCC Y726 T ; MycoBank MB808598) and Barnettozyma xylosica sp. nov. (type strain 14Y196 T =NBRC 111558 T =InaCC Y1030 T ; MycoBank MB819485). Strain 14Y125 T belonging to the Wickerhamomyces clade is described as the type strain of Wickerhamomyces xylosivorus f.a., sp. nov. (type strain 14Y125 T =NBRC 111553 T =InaCC Y1026 T ; MycoBank MB819484).

  3. Molecular characterization of the probiotic strain Bacillus cereus var. toyoi NCIMB 40112 and differentiation from food poisoning strains.

    PubMed

    Klein, Günter

    2011-07-01

    Bacillus cereus var. toyoi strain NCIMB 40112 (Toyocerin), a probiotic authorized in the European Union as feed additive for swine, bovines, poultry, and rabbits, was characterized by DNA fingerprinting applying pulsed-field gel electrophoresis and multilocus sequence typing and was compared with reference strains (of clinical and environmental origins). The probiotic strain was clearly characterized by pulsed-field gel electrophoresis using the restriction enzymes Apa I and Sma I resulting in unique DNA patterns. The comparison to the clinical reference strain B. cereus DSM 4312 was done with the same restriction enzymes, and again a clear differentiation of the two strains was possible by the resulting DNA patterns. The use of the restriction enzymes Apa I and Sma I is recommended for further studies. Furthermore, multilocus sequence typing analysis revealed a sequence type (ST 111) that was different from all known STs of B. cereus strains from food poisoning incidents. Thus, a strain characterization and differentiation from food poisoning strains for the probiotic strain was possible. Copyright ©, International Association for Food Protection

  4. Rapid genotyping of Legionella pneumophila serogroup 1 strains by a novel DNA microarray-based assay during the outbreak investigation in Warstein, Germany 2013.

    PubMed

    Petzold, Markus; Ehricht, Ralf; Slickers, Peter; Pleischl, Stefan; Brockmann, Ansgar; Exner, Martin; Monecke, Stefan; Lück, Christian

    2017-06-01

    Between 1 August and 6 September 2013, an outbreak of Legionnaires' disease (LD) with 78 cases confirmed by positive urinary antigen tests occurred in Warstein, North Rhine-Westphalia, Germany. Legionella (L.) pneumophila, serogroup (Sg) 1, monoclonal antibody (mAb) subgroup Knoxville, sequence type (ST) 345, was identified as the epidemic strain. This strain was isolated from seven patients. To detect the source of the infection, epidemiological typing of clinical and environmental strains was performed in two consecutive steps. First, strains were typed by monoclonal antibodies. Indistinguishable strains were further subtyped by sequence-based typing (SBT) which is the internationally recognized standard method for epidemiological genotyping of L. pneumophila. In an early stage of the outbreak investigation, many environmental isolates were found to belong to the mAb subgroup Knoxville, but to two different STs, namely to ST 345, the epidemic strain, and to ST 600. A majority of environmental isolates belonged to ST 600 whereas the epidemic ST 345 strain was less common in environmental samples. To rapidly distinguish both Knoxville strains, we applied a novel typing method based on DNA-hybridization on glass chips. The new assay can easily and rapidly discriminate L. pneumophila Sg 1 strains. Thus, we were able to quickly identify the sources harboring the epidemic strain, i.e., two cooling towers of different companies, the waste water treatment plants (WWTP) of the city and one company as well as water samples of the river Wester and its branches. Copyright © 2016 Elsevier GmbH. All rights reserved.

  5. Prevalence and characterization of multidrug-resistant (type ACSSuT) Salmonella enterica serovar Typhimurium strains in isolates from four gosling farms and a hatchery farm.

    PubMed

    Yu, Chang-You; Chou, Shih-Jen; Yeh, Chia-Ming; Chao, Maw-Rong; Huang, Kwo-Ching; Chang, Yung-Fu; Chiou, Chien-Shun; Weill, Francois-Xavier; Chiu, Cheng-Hsun; Chu, Chi-Hong; Chu, Chishih

    2008-02-01

    Salmonella enterica serovar Typhimurium strains of phage types DT104 and U302 are often resistant to ampicillin, chloramphenicol, streptomycin, sulfonamides, and tetracycline (the ACSSuT resistance type) and are major zoonotic pathogens. Increased consumption of goose meat may enhance the risk of transferring S. enterica serovar Typhimurium and other enteric pathogens from geese to human due to the consumption of meats from infected geese or improper preparation of meats. Therefore, we characterized S. enterica serovar Typhimurium strains isolated from four goose farms (farms A, B, C, and D) and one hatchery farm (farm E) to determine the epidemic and genetic differences among them. Antibiotic susceptibility tests and multiplex PCR confirmed that 77.6% (52/67) of strains were ACSSuT strains isolated from farms A, C, and E. Antibiotic-susceptible strains were isolated mostly from farm B, and no strain was observed in farm D. All ACSSuT strains harbored a 94.7-kb virulence plasmid and contained one 1.1-kb conserved segment identical to that of Salmonella genomic island 1. Four genotypes were determined among these S. enterica serovar Typhimurium isolates by pulsed-field gel electrophoresis analysis of XbaI-digested DNA fragments. Most isolates (85.29%; 29/34) of major genotype Ib were ACSSuT strains isolated mainly from goslings of farm C and egg membranes of farm E, a hatchery farm, suggesting that S. enterica serovar Typhimurium strains in isolates from goslings might originate from its hatchery, from the egg membranes to the gosling fluff after hatching. Multiple phage types, types 8, 12, U283, DT104, and U302, were identified. In conclusion, geese were a reservoir of diverse multidrug-resistant (type ACSSuT) S. enterica serovar Typhimurium strains, and each farm was colonized with genetically closely related S. enterica serovar Typhimurium strains.

  6. Transfer of Bacillus halodenitrificans Denariaz et al. 1989 to the genus Virgibacillus as Virgibacillus halodenitrificans comb. nov.

    PubMed

    Yoon, Jung-Hoon; Oh, Tae-Kwang; Park, Yong-Ha

    2004-11-01

    A Gram-variable, endospore-forming moderately halophilic rod, strain SF-121, was isolated from a marine solar saltern of the Yellow Sea in Korea. The result of 16S rRNA gene sequence analysis showed that strain SF-121 has highest sequence similarity (99.7 %) with the type strain of Bacillus halodenitrificans. Phylogenetic analyses based on 16S rRNA gene sequences revealed that B. halodenitrificans DSM 10037(T) and strain SF-121 are more closely related to the genus Virgibacillus than to the genus Bacillus. Strain SF-121 and B. halodenitrificans DSM 10037(T) exhibited 16S rRNA gene similarity levels of 95.3-97.5 % with the type strains of Virgibacillus species and 94.0 % with the type strain of Bacillus subtilis. DNA-DNA relatedness and phenotypic data indicated that B. halodenitrificans DSM 10037(T) and strain SF-121 are members of the same species. B. halodenitrificans DSM 10037(T) and strain SF-121 exhibited DNA-DNA relatedness values of 9-11 % with the type strains of Virgibacillus carmonensis and Virgibacillus marismortui. On the basis of the phenotypic, chemotaxonomic, phylogenetic and genetic data, B. halodenitrificans should be reclassified in the genus Virgibacillus as Virgibacillus halodenitrificans comb. nov.

  7. Avian-pathogenic Escherichia coli strains are similar to neonatal meningitis E. coli strains and are able to cause meningitis in the rat model of human disease.

    PubMed

    Tivendale, Kelly A; Logue, Catherine M; Kariyawasam, Subhashinie; Jordan, Dianna; Hussein, Ashraf; Li, Ganwu; Wannemuehler, Yvonne; Nolan, Lisa K

    2010-08-01

    Escherichia coli strains causing avian colibacillosis and human neonatal meningitis, urinary tract infections, and septicemia are collectively known as extraintestinal pathogenic E. coli (ExPEC). Characterization of ExPEC strains using various typing techniques has shown that they harbor many similarities, despite their isolation from different host species, leading to the hypothesis that ExPEC may have zoonotic potential. The present study examined a subset of ExPEC strains: neonatal meningitis E. coli (NMEC) strains and avian-pathogenic E. coli (APEC) strains belonging to the O18 serogroup. The study found that they were not easily differentiated on the basis of multilocus sequence typing, phylogenetic typing, or carriage of large virulence plasmids. Among the APEC strains examined, one strain was found to be an outlier, based on the results of these typing methods, and demonstrated reduced virulence in murine and avian pathogenicity models. Some of the APEC strains tested in a rat model of human neonatal meningitis were able to cause meningitis, demonstrating APEC's ability to cause disease in mammals, lending support to the hypothesis that APEC strains have zoonotic potential. In addition, some NMEC strains were able to cause avian colisepticemia, providing further support for this hypothesis. However, not all of the NMEC and APEC strains tested were able to cause disease in avian and murine hosts, despite the apparent similarities in their known virulence attributes. Thus, it appears that a subset of NMEC and APEC strains harbors zoonotic potential, while other strains do not, suggesting that unknown mechanisms underlie host specificity in some ExPEC strains.

  8. Effects of Age, Hemoglobin Type and Parasite Strain on IgG Recognition of Plasmodium falciparum–Infected Erythrocytes in Malian Children

    PubMed Central

    Zeituni, Amir E.; Miura, Kazutoyo; Diakite, Mahamadou; Doumbia, Saibou; Moretz, Samuel E.; Diouf, Ababacar; Tullo, Gregory; Lopera-Mesa, Tatiana M.; Bess, Cameron D.; Mita-Mendoza, Neida K.; Anderson, Jennifer M.; Fairhurst, Rick M.; Long, Carole A.

    2013-01-01

    Background Naturally-acquired antibody responses to antigens on the surface of Plasmodium falciparum-infected red blood cells (iRBCs) have been implicated in antimalarial immunity. To profile the development of this immunity, we have been studying a cohort of Malian children living in an area with intense seasonal malaria transmission. Methodology/Principal Findings We collected plasma from a sub-cohort of 176 Malian children aged 3-11 years, before (May) and after (December) the 2009 transmission season. To measure the effect of hemoglobin (Hb) type on antibody responses, we enrolled age-matched HbAA, HbAS and HbAC children. To quantify antibody recognition of iRBCs, we designed a high-throughput flow cytometry assay to rapidly test numerous plasma samples against multiple parasite strains. We evaluated antibody reactivity of each plasma sample to 3 laboratory-adapted parasite lines (FCR3, D10, PC26) and 4 short-term-cultured parasite isolates (2 Malian and 2 Cambodian). 97% of children recognized ≥1 parasite strain and the proportion of IgG responders increased significantly during the transmission season for most parasite strains. Both strain-specific and strain-transcending IgG responses were detected, and varied by age, Hb type and parasite strain. In addition, the breadth of IgG responses to parasite strains increased with age in HbAA, but not in HbAS or HbAC, children. Conclusions/Significance Our assay detects both strain-specific and strain-transcending IgG responses to iRBCs. The magnitude and breadth of these responses varied not only by age, but also by Hb type and parasite strain used. These findings indicate that studies of acquired humoral immunity should account for Hb type and test large numbers of diverse parasite strains. PMID:24124591

  9. Aestuariispira insulae gen. nov., sp. nov., a lipolytic bacterium isolated from a tidal flat.

    PubMed

    Park, Sooyeon; Park, Ji-Min; Kang, Chul-Hyung; Yoon, Jung-Hoon

    2014-06-01

    A Gram-stain-negative, non-motile, aerobic, curved-to-spiral-rod-shaped bacterium, designated AH-MY2(T), was isolated from a tidal flat on Aphae island in the sea to the south-west of South Korea, and its taxonomic position was investigated using a polyphasic taxonomic approach. Strain AH-MY2(T) grew optimally at 30 °C, at pH 7.0-8.0 and in the presence of 2.0% (w/v) NaCl. Neighbour-joining, maximum-likelihood and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences showed that strain AH-MY2(T) clustered with the type strain of Terasakiella pusilla and that this cluster joined the clade comprising the type strains of species of the genus Thalassospira. Strain AH-MY2(T) exhibited 16S rRNA gene sequence similarity values of 90.6% to the type strain of Terasakiella pusilla and of less than 91.0% to the type strains of other species with validly published names. Strain AH-MY2(T) contained Q-10 as the predominant ubiquinone and C(18 : 1)ω7c as the major fatty acid. The major polar lipids detected in strain AH-MY2(T) were phosphatidylglycerol, phosphatidylethanolamine, two unidentified aminolipids and one unidentified glycolipid. The DNA G+C content of strain AH-MY2(T) was 56.0 mol%. The phylogenetic data and differential chemotaxonomic and other phenotypic properties revealed that strain AH-MY2(T) represented a novel genus and species within the family Rhodospirillaceae of the class Alphaproteobacteria, for which the name Aestuariispira insulae gen. nov., sp. nov. is proposed. The type strain of Aestuariispira insulae is AH-MY2(T) ( = KCTC 32577(T) = CECT 8488(T)). © 2014 IUMS.

  10. Comparative pathogenomics of Clostridium tetani.

    PubMed

    Cohen, Jonathan E; Wang, Rong; Shen, Rong-Fong; Wu, Wells W; Keller, James E

    2017-01-01

    Clostridium tetani and Clostridium botulinum produce two of the most potent neurotoxins known, tetanus neurotoxin and botulinum neurotoxin, respectively. Extensive biochemical and genetic investigation has been devoted to identifying and characterizing various C. botulinum strains. Less effort has been focused on studying C. tetani likely because recently sequenced strains of C. tetani show much less genetic diversity than C. botulinum strains and because widespread vaccination efforts have reduced the public health threat from tetanus. Our aim was to acquire genomic data on the U.S. vaccine strain of C. tetani to better understand its genetic relationship to previously published genomic data from European vaccine strains. We performed high throughput genomic sequence analysis on two wild-type and two vaccine C. tetani strains. Comparative genomic analysis was performed using these and previously published genomic data for seven other C. tetani strains. Our analysis focused on single nucleotide polymorphisms (SNP) and four distinct constituents of the mobile genome (mobilome): a hypervariable flagellar glycosylation island region, five conserved bacteriophage insertion regions, variations in three CRISPR (clustered regularly interspaced short palindromic repeats)-Cas (CRISPR-associated) systems, and a single plasmid. Intact type IA and IB CRISPR/Cas systems were within 10 of 11 strains. A type IIIA CRISPR/Cas system was present in two strains. Phage infection histories derived from CRISPR-Cas sequences indicate C. tetani encounters phages common among commensal gut bacteria and soil-borne organisms consistent with C. tetani distribution in nature. All vaccine strains form a clade distinct from currently sequenced wild type strains when considering variations in these mobile elements. SNP, flagellar glycosylation island, prophage content and CRISPR/Cas phylogenic histories provide tentative evidence suggesting vaccine and wild type strains share a common ancestor.

  11. Magnetic orders of LaTiO3 under epitaxial strain: A first-principles study

    NASA Astrophysics Data System (ADS)

    Weng, Yakui; Huang, Xin; Tang, Yankun; Dong, Shuai

    2014-05-01

    Perovskite LaTiO3 bulk is a typical Mott-insulator with G-type antiferromagnetic order. In this work, the biaxial strain effects on the ground magnetic order of LaTiO3 films grown on various substrates have been studied. For the compressive strain, LaTiO3 films grown on LaAlO3, LaGaO3, and SrTiO3 substrates undergo a phase transition from the original G-type antiferromagnet to A-type antiferromagnet. The underlying physical mechanisms are the lattice distortions tunned by strain. While for the tensile strain, the BaTiO3 and LaScO3 substrates have been tested, which show a tendency to transit the LaTiO3 to the C-type antiferromagnet. Furthermore, our calculations find that the magnetic transitions under epitaxial strain do not change the insulating fact of LaTiO3.

  12. The properties given at the time of publication for the designated type strain of Leifsonia rubra Reddy et al. 2003, CMS 76r, do not correspond with those of MTCC 4210, DSM 15304, CIP 107783 and JCM 12471 that are deposited as representing the type strain: Opinion 96. Judicial Commission of the International Committee on Systematics of Prokaryotes.

    PubMed

    Tindall, B J

    2014-10-01

    The Judicial Commission affirms that, according to information presented to it, the type strain of Leifsonia rubra Reddy et al. 2003 designated in the original publication as strain CMS 76r and deposited as MTCC 4210, DSM 15304, CIP 107783 and JCM 12471 does not have properties corresponding with those of the strains held in those collections under those accession numbers. The species Leifsonia rubra Reddy et al. 2003 was not represented by an authentic deposit of a type strain at the time of effective publication in the pages of the International Journal of Systematic and Evolutionary Microbiology. IUMS.

  13. Development of a molecular method for the typing of Brettanomyces bruxellensis (Dekkera bruxellensis) at the strain level.

    PubMed

    Miot-Sertier, C; Lonvaud-Funel, A

    2007-02-01

    In recent years, Brettanomyces/Dekkera bruxellensis has caused increasingly severe quality problems in the wine industry. A typing method at the strain level is needed for a better knowledge of the dispersion and the dynamics of these yeasts from grape to wine. Three molecular tools, namely random-amplified polymorphic DNA, PCR fingerprinting with microsatellite oligonucleotide primers and SAU-PCR, were explored for their relevance to typing strains of Brettanomyces bruxellensis. The results indicated that discrimination of each individual strain was not possible with a single PCR typing technique. We described a typing method for B. bruxellensis based on restriction enzyme analysis and pulse field gel electrophoresis (REA-PFGE). Results showed that electrophoretic profiles were reproducible and specific for each strain under study. Consequently, REA-PFGE should be considered for the discrimination of B. bruxellensis strains. This technique allowed a fine discrimination of B. bruxellensis, as strains were identified by a particular profile. This study constitutes a prerequisite for accurate and appropriate investigations on the diversity of strains throughout the winemaking and ageing process. Such studies will probably give clearer and more up-to-date information on the origin of the presence of Brettanomyces in wine after vinification when they are latent spoilage agents.

  14. Multilocus sequence typing analyses of Clostridium perfringens type A strains harboring tpeL and netB genes.

    PubMed

    Nakano, V; Ignacio, A; Llanco, L; Bueris, V; Sircili, M P; Avila-Campos, M J

    2017-04-01

    Clostridium perfringens is an anaerobic bacterium ubiquitous in various environments, especially in soil and the gastrointestinal tract of healthy humans and animals. In this study, multilocus sequence typing protocol was used to investigate genotypic relationships among 40 C. perfringens strains isolated from humans and broiler chicken with necrotic enteritis [NE]. The results indicated a few clonal populations, mainly observed in human strains, with 32.5% of all strains associated with one of three clonal complexes and 30 sequences types. The CC-1 cluster showed an interesting and unexpected result because it contained seven strains [six from animals and one of human origin]. Detection assays for toxin genes tpeL and netB were also performed. The netB gene was only observed in 7.5% of the strains from healthy human. The toxin gene tpeL was detected in 22.5% of the C. perfringens strains isolated from three individuals and in six broilers with NE. Our study describes the role of some C. perfringens strains of human origin acting as reservoirs of virulence genes and sources of infection. In addition, the strains of human and animal origin were found to be genetically distinct but phylogenetically close, and the human strains showed more diversity than the animal strains. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Antigenic and molecular characterization of Vibrio ordalii strains isolated from Atlantic salmon Salmo salar in Chile.

    PubMed

    Silva-Rubio, Andrés; Acevedo, Claudia; Magariños, Beatriz; Jaureguiberry, Beltrán; Toranzo, Alicia E; Avendaño-Herrera, Ruben

    2008-03-03

    Biochemical, serological and molecular properties of a group of 14 Vibrio ordalii strains isolated from cultured Atlantic salmon Salmo salar in Chile in recent years were studied. The characteristics of isolates were compared with the type strain V. ordalii ATCC 33509T. The Chilean V. ordalii represented a biochemically homogenous group; however, some minor differences with the type strain were observed. The serological relationships among isolates, as well as the study of their antigenic determinant (LPS) revealed a strong reaction with antisera raised against Atlantic salmon strains and the antiserum raised against Listonella anguillarum serotype O2. However, LPS electrophoretic patterns were completely different from the V. ordalii type strain, regardless of the serum employed, suggesting the possibility that the Chilean strains constitute a new serological subgroup within this bacterial species. Genetic analyses by PFGE, RAPD, REP-PCR and ERIC-PCR demonstrated that all V. ordalii strains were genetically homogenous, displaying similar DNA patterns, regardless of the techniques used. Moreover, the analysis of DNA banding patterns generated by ERIC-PCR and REP-PCR also clearly separated the type strain from the Chilean strains. This is the first report of characterization of V. ordalii strains from the Southeastern Pacific area, the results of which should facilitate the development of vaccines for protecting cultured Atlantic salmon against vibriosis in this area.

  16. VARIATION AND TYPE SPECIFICITY IN THE BACTERIAL SPECIES HEMOPHILUS INFLUENZAE

    PubMed Central

    Pittman, Margaret

    1931-01-01

    During the course of a study of different strains of influenza bacilli, fifteen strains have been found to form colonies of a different appearance from that usually considered typical of influenza bacilli. These colonies are smooth, more opaque, and are iridescent in oblique transmitted light. Most of these strains were isolated from patients in whom these organisms seemed to play a pathogenic rô1e. When these strains were grown repeatedly on blood agar, other colonies appeared which were smaller, less smooth, less opaque, and not iridescent, and when subcultures were made from these rough colonies, all of the colonies were of this character. Further study of the cultures obtained from these smooth and rough colonies have shown that one is a variant of the other. The strain from the smooth colony has been called an S strain, that from the rough colony an R strain. Certain differences in the morphology of the organisms in the R and S strains have been observed. Of special importance is the fact that the bacteria of the S strains are possessed of capsules. It has also been found that the S strains are somewhat more virulent for laboratory animals than are the R strains. In the supernatant fluid of broth cultures of S strains, and in the washing fluid of S bacteria grown on agar, there is present a soluble substance which, in the presence of homologous immune serum, gives rise to a precipitate. No reaction of this kind, however, occurs with the cultures of the R strains. By means of cross precipitin reactions, employing antisera against the different S strains, it has been found that the fifteen strains studied may be divided into two distinct immunological groups. Three of these strains belong in one group, Type a, and the remaining twelve in another group, Type b. Seven of the strains studied were isolated from the spinal fluid in cases of meningitis, and all of these strains are of Type b. Agglutination tests performed at 37°C. with these fifteen S strains have revealed the same specific type relationships among the organisms as did the precipitin tests. The R strains on the other hand, exhibit no similar type agglutinations. If the agglutination tests are made at a higher temperature, 47°C., the S strains also fail to show the specific type reactions which occur at 37°C. Certain differences between other biochemical reactions exhibited by the two types of strains have been noted, but it is not believed that they are sufficiently constant to be of great significance. When S strains are grown on artificial media outside the animal body, they tend to be converted into the R form. The rapidity and the readiness with which this conversion occurs depend on certain conditions, such as the kind of media employed, the temperature at which the cultures are kept, and the atmospheric conditions under which they are cultivated. The rate of conversion is increased when the S strains are grown in media containing anti-S immune serum of the homologous type. On the other hand, conversion of R strains into the S form occurs with much less readiness, and then only if very particular conditions are present. On one occasion conversion occurred when an R strain was grown in a medium containing anti-R immune serum. On two other occasions this same strain changed from the R to the S form during passage through animals. With other R strains it has so far been impossible to bring about this transformation. These studies indicate that the bacteria belonging in the group Hemophilus influenzae exhibit changes in pathogenicity and immunological specificity, which are analogous to those shown by the bacteria of the pneumococcus group. It is important to continue this study, with the technique which has been developed, to include a much larger number of strains. On account of the readiness with which the S strains of influenza bacilli lose their type specificity when grown on artificial culture media, it is important that the organisms be studied as soon as possible after removal from their pathological sources. It is not impossible that many strains lose their specificity immediately after removal from the host, and that the specific immunological differentiation of many strains may, for that reason, be very difficult, if not impossible. PMID:19869858

  17. Genomic Encyclopedia of Bacterial and Archaeal Type Strains, Phase III: the genomes of soil and plant-associated and newly described type strains

    DOE PAGES

    Whitman, William B.; Woyke, Tanja; Klenk, Hans-Peter; ...

    2015-05-17

    The Genomic Encyclopedia of Bacteria and Archaea (GEBA) project was launched by the JGI in 2007 as a pilot project to sequence about 250 bacterial and archaeal genomes of elevated phylogenetic diversity. Here in this paper, we propose to extend this approach to type strains of prokaryotes associated with soil or plants and their close relatives as well as type strains from newly described species. Understanding the microbiology of soil and plants is critical to many DOE mission areas, such as biofuel production from biomass, biogeochemistry, and carbon cycling. We are also targeting type strains of novel species while theymore » are being described. Since 2006, about 630 new species have been described per year, many of which are closely aligned to DOE areas of interest in soil, agriculture, degradation of pollutants, biofuel production, biogeochemical transformation, and biodiversity« less

  18. Genomic Encyclopedia of Bacterial and Archaeal Type Strains, Phase III: the genomes of soil and plant-associated and newly described type strains

    PubMed Central

    2015-01-01

    The Genomic Encyclopedia of Bacteria and Archaea (GEBA) project was launched by the JGI in 2007 as a pilot project to sequence about 250 bacterial and archaeal genomes of elevated phylogenetic diversity. Herein, we propose to extend this approach to type strains of prokaryotes associated with soil or plants and their close relatives as well as type strains from newly described species. Understanding the microbiology of soil and plants is critical to many DOE mission areas, such as biofuel production from biomass, biogeochemistry, and carbon cycling. We are also targeting type strains of novel species while they are being described. Since 2006, about 630 new species have been described per year, many of which are closely aligned to DOE areas of interest in soil, agriculture, degradation of pollutants, biofuel production, biogeochemical transformation, and biodiversity. PMID:26203337

  19. Genomic Encyclopedia of Bacterial and Archaeal Type Strains, Phase III: the genomes of soil and plant-associated and newly described type strains

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Whitman, William B.; Woyke, Tanja; Klenk, Hans-Peter

    The Genomic Encyclopedia of Bacteria and Archaea (GEBA) project was launched by the JGI in 2007 as a pilot project to sequence about 250 bacterial and archaeal genomes of elevated phylogenetic diversity. Here in this paper, we propose to extend this approach to type strains of prokaryotes associated with soil or plants and their close relatives as well as type strains from newly described species. Understanding the microbiology of soil and plants is critical to many DOE mission areas, such as biofuel production from biomass, biogeochemistry, and carbon cycling. We are also targeting type strains of novel species while theymore » are being described. Since 2006, about 630 new species have been described per year, many of which are closely aligned to DOE areas of interest in soil, agriculture, degradation of pollutants, biofuel production, biogeochemical transformation, and biodiversity« less

  20. Rotavirus A genotype G1P[8]: a novel method to distinguish wild-type strains from the Rotarix vaccine strain.

    PubMed

    Rose, Tatiana L; Miagostovich, Marize P; Leite, José Paulo G

    2010-12-01

    Rotaviruses are important enteric pathogens for humans and animals. Group A rotaviruses (RV-A) are the most common agents of severe gastroenteritis in infants and young children and vaccination is the most effective method to reduce RV-A-associated diseases. G1P[8], the most prevalent RV-A genotype worldwide, is included in the RV-A vaccine Rotarix®. The discrimination between wild-type G1P[8] and vaccine G1P[8] strains is an important topic in the study of RV-A epidemiology to manage outbreaks and to define control measures for vaccinated children. In this study, we developed a novel method to segregate the wild-type and vaccine strains using restriction endonucleases. The dsRNA from the Rotarix® vaccine was sequenced and the NSP3 gene was selected as the target gene. The vaccine strain has a restriction pattern that is different than that of wild-type RV-A G1P[8] isolates after digestion with the restriction endonuclease BspHI. This pattern could be used as a marker for the differentiation of wild-type G1P[8] strains from the vaccine strain.

  1. Comparison of arbitrarily primed PCR and macrorestriction (pulsed-field gel electrophoresis) typing of Pseudomonas aeruginosa strains from cystic fibrosis patients.

    PubMed Central

    Kersulyte, D; Struelens, M J; Deplano, A; Berg, D E

    1995-01-01

    Arbitrarily primed PCR fingerprinting was carried out on 43 Pseudomonas aeruginosa isolates from cystic fibrosis (CF) patients. Seventeen major groups of strains that coincided with groups also distinguished by macrorestriction (pulsed-field gel electrophoresis) typing were identified. Our results illustrated that a CF patient can carry more than one strain and can carry a given strain for long periods of time and that strains can evolve by changes in drug resistance or other phenotypic traits during long-term colonization. The arbitrarily primed PCR method is recommended for first-pass screening of P. aeruginosa isolates from CF patients, especially when many strains are to be typed, because of its sensitivity and efficiency. PMID:7559985

  2. Application of Pulsed-Field Gel Electrophoresis and Binary Typing as Tools in Veterinary Clinical Microbiology and Molecular Epidemiologic Analysis of Bovine and Human Staphylococcus aureus Isolates

    PubMed Central

    Zadoks, Ruth; van Leeuwen, Willem; Barkema, Herman; Sampimon, Otlis; Verbrugh, Henri; Schukken, Ynte Hein; van Belkum, Alex

    2000-01-01

    Thirty-eight bovine mammary Staphylococcus aureus isolates from diverse clinical, temporal, and geographical origins were genotyped by pulsed-field gel electrophoresis (PFGE) after SmaI digestion of prokaryotic DNA and by means of binary typing using 15 strain-specific DNA probes. Seven pulsed-field types and four subtypes were identified, as were 16 binary types. Concordant delineation of genetic relatedness was documented by both techniques, yet based on practical and epidemiological considerations, binary typing was the preferable method. Genotypes of bovine isolates were compared to 55 previously characterized human S. aureus isolates through cluster analysis of binary types. Genetic clusters containing strains of both human and bovine origin were found, but bacterial genotypes were predominantly associated with a single host species. Binary typing proved an excellent tool for comparison of S. aureus strains, including methicillin-resistant S. aureus, derived from different host species and from different databases. For 28 bovine S. aureus isolates, detailed clinical observations in vivo were compared to strain typing results in vitro. Associations were found between distinct genotypes and severity of disease, suggesting strain-specific bacterial virulence. Circumstantial evidence furthermore supports strain-specific routes of bacterial dissemination. We conclude that PFGE and binary typing can be successfully applied for genetic analysis of S. aureus isolates from bovine mammary secretions. Binary typing in particular is a robust and simple method and promises to become a powerful tool for strain characterization, for resolution of clonal relationships of bacteria within and between host species, and for identification of sources and transmission routes of bovine S. aureus. PMID:10790124

  3. SNP-Based Typing: A Useful Tool to Study Bordetella pertussis Populations

    PubMed Central

    van der Heide, Han G. J.; Heuvelman, Kees J.; Kallonen, Teemu; He, Qiushui; Mertsola, Jussi; Advani, Abdolreza; Hallander, Hans O.; Janssens, Koen; Hermans, Peter W.; Mooi, Frits R.

    2011-01-01

    To monitor changes in Bordetella pertussis populations, mainly two typing methods are used; Pulsed-Field Gel Electrophoresis (PFGE) and Multiple-Locus Variable-Number Tandem Repeat Analysis (MLVA). In this study, a single nucleotide polymorphism (SNP) typing method, based on 87 SNPs, was developed and compared with PFGE and MLVA. The discriminatory indices of SNP typing, PFGE and MLVA were found to be 0.85, 0.95 and 0.83, respectively. Phylogenetic analysis, using SNP typing as Gold Standard, revealed false homoplasies in the PFGE and MLVA trees. Further, in contrast to the SNP-based tree, the PFGE- and MLVA-based trees did not reveal a positive correlation between root-to-tip distance and the isolation year of strains. Thus PFGE and MLVA do not allow an estimation of the relative age of the selected strains. In conclusion, SNP typing was found to be phylogenetically more informative than PFGE and more discriminative than MLVA. Further, in contrast to PFGE, it is readily standardized allowing interlaboratory comparisons. We applied SNP typing to study strains with a novel allele for the pertussis toxin promoter, ptxP3, which have a worldwide distribution and which have replaced the resident ptxP1 strains in the last 20 years. Previously, we showed that ptxP3 strains showed increased pertussis toxin expression and that their emergence was associated with increased notification in the Netherlands. SNP typing showed that the ptxP3 strains isolated in the Americas, Asia, Australia and Europe formed a monophyletic branch which recently diverged from ptxP1 strains. Two predominant ptxP3 SNP types were identified which spread worldwide. The widespread use of SNP typing will enhance our understanding of the evolution and global epidemiology of B. pertussis. PMID:21647370

  4. Nonparametric Statistics Test Software Package.

    DTIC Science & Technology

    1983-09-01

    statis- tics because of their acceptance in the academic world, the availability of computer support, and flexibility in model builling. Nonparametric...25 I1l,lCELL WRITE(NCF,12 ) IvE (I ,RCCT(I) 122 FORMAT(IlXt 3(H5 9 1) IF( IeLT *NCELL) WRITE (NOF1123 J PARTV(I1J 123 FORMAT( Xll----’,FIo.3J 25 CONT

  5. 75 FR 3874 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Participating in the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-25

    .... 0810141351-9087-02] RIN 0648-XT95 Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Participating in the Amendment 80 Limited Access Fishery in Bering Sea and Aleutian Islands Management Area... management area (BSAI). This action is necessary to prevent exceeding the 2010 Pacific cod total allowable...

  6. 75 FR 3873 - Fisheries of the Exclusive Economic Zone Off Alaska; Atka Mackerel in the Bering Sea and Aleutian...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-25

    .... 0810141351-9087-02] RIN 0648-XT97 Fisheries of the Exclusive Economic Zone Off Alaska; Atka Mackerel in the Bering Sea and Aleutian Islands Management Area AGENCY: National Marine Fisheries Service (NMFS... and the Bering Sea subarea of the Bering Sea and Aleutian Islands management area (BSAI) for vessels...

  7. Relating Time-Dependent Acceleration and Height Using an Elevator

    ERIC Educational Resources Information Center

    Kinser, Jason M.

    2015-01-01

    A simple experiment in relating a time-dependent linear acceleration function to height is explored through the use of a smartphone and an elevator. Given acceleration as a function of time, a(t), the velocity function and position functions are determined through integration as in v(t)=? a(t) dt (1) and x(t)=? v(t) dt. Mobile devices such as…

  8. 37 CFR 1.824 - Form and format for nucleotide and/or amino acid sequence submissions in computer readable form.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... which the data were recorded on the computer readable form, the operating system used, a reference... in a self-extracting format that will decompress on one of the systems described in paragraph (b) of... these format requirements: (1) Computer Compatibility: IBM PC/XT/AT or Apple Macintosh; (2) Operating...

  9. The USL NASA PC R and D project: General specifications of objectives

    NASA Technical Reports Server (NTRS)

    Dominick, Wayne D. (Editor)

    1984-01-01

    Given here are the general specifications of the objectives of the University of Southwestern Louisiana Data Base Management System (USL/DBMS) NASA PC R and D Project, a project initiated to address future R and D issues related to PC-based processing environments acquired pursuant to the NASA contract work; namely, the IBM PC/XT systems.

  10. Sustained Effects of Ecstasy on the Human Brain: A Prospective Neuroimaging Study in Novel Users

    ERIC Educational Resources Information Center

    de Win, Maartje M. L.; Jager, Gerry; Booij, Jan; Reneman, Liesbeth; Schilt, Thelma; Lavini, Christina; Olabarriaga, Silvia D.; den Heeten, Gerard J.; van den Brink, Wim

    2008-01-01

    Previous studies have suggested toxic effects of recreational ecstasy use on the serotonin system of the brain. However, it cannot be excluded that observed differences between users and non-users are the cause rather than the consequence of ecstasy use. As part of the Netherlands XTC Toxicity (NeXT) study, we prospectively assessed sustained…

  11. The USL NASA PC R and D development environment standards

    NASA Technical Reports Server (NTRS)

    Dominick, Wayne D. (Editor); Moreau, Dennis R.

    1984-01-01

    The development environment standards which have been established in order to control usage of the IBM PC/XT development systems and to prevent interference between projects being currently developed on the PC's are discussed. The standards address the following areas: scheduling PC resources; login/logout procedures; training; file naming conventions; hard disk organization; diskette care; backup procedures; and copying policies.

  12. Modeling of Hurricane Impacts

    DTIC Science & Technology

    2007-09-01

    terms on the RHS). The wave number k is obtained from the eikonal equations (e.g. Dingemans, 1993): ⎟⎟ ⎠ ⎞ ⎜⎜ ⎝ ⎛ ∂ ∂ − ∂ ∂ −= ∂ ∂ + ∂ ∂ y k x k c xt...components and ω represents the absolute radial frequency. The RHS of the eikonal equations ensures the irrotationality of wave number vector field (pers

  13. Identification of vaccine-derived rotavirus strains in children with acute gastroenteritis in Japan, 2012-2015.

    PubMed

    Kaneko, Mei; Takanashi, Sayaka; Thongprachum, Aksara; Hanaoka, Nozomu; Fujimoto, Tsuguto; Nagasawa, Koo; Kimura, Hirokazu; Okitsu, Shoko; Mizuguchi, Masashi; Ushijima, Hiroshi

    2017-01-01

    Two live attenuated oral rotavirus vaccines, Rotarix and RotaTeq, have been introduced as voluntary vaccination in Japan since 2011 and 2012, respectively. Effectiveness of the vaccines has been confirmed, whereas concerns such as shedding of the vaccine strains and gastroenteritis cases caused by vaccine strains are not well assessed. We aimed to identify the vaccine strains in children with acute gastroenteritis (AGE) to investigate the prevalence of AGE caused by vaccination or horizontal transmission of vaccine strains. A total of 1,824 stool samples were collected from children with AGE at six outpatient clinics in 2012-2015. Among all, 372 group A rotavirus (RVA) positive samples were screened for vaccine components by real-time RT-PCR which were designed to differentiate vaccine strains from rotavirus wild-type strains with high specificity. For samples possessing both vaccine and wild-type strains, analyses by next-generation sequencing (NGS) were conducted to characterize viruses existed in the intestine. As a result, Rotarix-derived strains were identified in 6 of 372 (1.6%) RVA positive samples whereas no RotaTeq strain was detected. Among six samples, four possessed Rotarix-derived strains while two possessed both Rotarix-derived strains and wild-type strains. In addition, other pathogens such as norovirus, enterovirus and E.coli were detected in four samples. The contribution of these vaccine strains to each patient's symptoms was unclear as all of the cases were vaccinated 2-14 days before sample collection. Proportion of average coverage for each segmented gene by NGS strongly suggested the concurrent infection of the vaccine-derived strain and the wild-type strain rather than reassortment of these two strains in one sample. This is the first study to report the prevalence of vaccine-derived strains in patients with RVA AGE in Japan as 1.6% without evidence of horizontal transmission. The results emphasized the importance of continuous monitoring on vaccine strains and their clinical impacts on children.

  14. Identification of vaccine-derived rotavirus strains in children with acute gastroenteritis in Japan, 2012-2015

    PubMed Central

    Kaneko, Mei; Thongprachum, Aksara; Hanaoka, Nozomu; Fujimoto, Tsuguto; Nagasawa, Koo; Kimura, Hirokazu; Okitsu, Shoko; Mizuguchi, Masashi; Ushijima, Hiroshi

    2017-01-01

    Two live attenuated oral rotavirus vaccines, Rotarix and RotaTeq, have been introduced as voluntary vaccination in Japan since 2011 and 2012, respectively. Effectiveness of the vaccines has been confirmed, whereas concerns such as shedding of the vaccine strains and gastroenteritis cases caused by vaccine strains are not well assessed. We aimed to identify the vaccine strains in children with acute gastroenteritis (AGE) to investigate the prevalence of AGE caused by vaccination or horizontal transmission of vaccine strains. A total of 1,824 stool samples were collected from children with AGE at six outpatient clinics in 2012–2015. Among all, 372 group A rotavirus (RVA) positive samples were screened for vaccine components by real-time RT-PCR which were designed to differentiate vaccine strains from rotavirus wild-type strains with high specificity. For samples possessing both vaccine and wild-type strains, analyses by next-generation sequencing (NGS) were conducted to characterize viruses existed in the intestine. As a result, Rotarix-derived strains were identified in 6 of 372 (1.6%) RVA positive samples whereas no RotaTeq strain was detected. Among six samples, four possessed Rotarix-derived strains while two possessed both Rotarix-derived strains and wild-type strains. In addition, other pathogens such as norovirus, enterovirus and E.coli were detected in four samples. The contribution of these vaccine strains to each patient’s symptoms was unclear as all of the cases were vaccinated 2–14 days before sample collection. Proportion of average coverage for each segmented gene by NGS strongly suggested the concurrent infection of the vaccine-derived strain and the wild-type strain rather than reassortment of these two strains in one sample. This is the first study to report the prevalence of vaccine-derived strains in patients with RVA AGE in Japan as 1.6% without evidence of horizontal transmission. The results emphasized the importance of continuous monitoring on vaccine strains and their clinical impacts on children. PMID:28902863

  15. A study of Salmonella typhi isolated in Suez Canal area. Biotyping, phage typing and colicinogenic property.

    PubMed

    Shoeb, S; Khalifa, I; el Daly, O; Heiba, A; Farmer, J; Brenner, F; el Batawi, Y

    1989-01-01

    In this work a total of 82 strains of Salmonella typhi were isolated from Egyptian patients diagnosed as quiry enteric fever. These cases were from Ismalia, Suez and port Said Areas. The strains fell in 16 phage types. Phage types N, 40, E1, and degraded Vi were the commonest phage type in Ismailia, while phage types degraded Vi and C1 were the commonest in Port Said. Phage types Di-N, degraded Vi, A and C1 were the commonest in Suez. Chemotyping of Salmonella typhi showed that the majority of the strains belonged to chemotype I (82%), and the rest belonged to chemotype II (18%). Colicin production was negative and all the strains were susceptible to the currently used antibiotics.

  16. Effect of moisture on dental enamel in the interaction of two orthodontic bonding systems.

    PubMed

    Bertoz, André Pinheiro de Magalhães; de Oliveira, Derly Tescaro Narcizo; Gimenez, Carla Maria Melleiro; Briso, André Luiz Fraga; Bertoz, Francisco Antonio; Santos, Eduardo César Almada

    2013-01-01

    The purpose of this study was to assess by means of scanning electron microscopy (SEM) the remaining adhesive interface after debonding orthodontic attachments bonded to bovine teeth with the use of hydrophilic and hydrophobic primers under different dental substrate moisture conditions. Twenty mandibular incisors were divided into four groups (n = 5). In Group I, bracket bonding was performed with Transbond MIP hydrophilic primer and Transbond XT adhesive paste applied to moist substrate, and in Group II a bonding system comprising Transbond XT hydrophobic primer and adhesive paste was applied to moist substrate. Brackets were bonded to the specimens in Groups III and IV using the same adhesive systems, but on dry dental enamel. The images were qualitatively assessed by SEM. The absence of moisture in etched enamel enabled better interaction between bonding materials and the adamantine structure. The hydrophobic primer achieved the worst micromechanical interlocking results when applied to a moist dental structure, whereas the hydrophilic system proved versatile, yielding acceptable results in moist conditions and excellent interaction in the absence of contamination. The authors assert that the best condition for the application of primers to dental enamel occurs in the absence of moisture.

  17. Evaluation of Vickers hardness and depth of cure of six composite resins photo-activated with different polymerization modes.

    PubMed

    Poggio, C; Lombardini, M; Gaviati, S; Chiesa, M

    2012-07-01

    The current in vitro study evaluated Vickers hardness (VK) and depth of cure (hardness ratio) of six resin composites, polymerized with a light-emitting diode (LED) curing unit by different polymerization modes: Standard 20 s, Standard 40 s, Soft-start 40 s. SIX RESIN COMPOSITES WERE SELECTED FOR THE PRESENT STUDY: three microhybrid (Esthet.X HD, Amaris, Filtek Silorane), two nanohybrid (Grandio, Ceram.X mono) and one nanofilled (Filtek Supreme XT). The VK of the surface was determined with a microhardness tester using a Vickers diamond indenter and a 200 g load applied for 15 seconds. The mean VK and hardness ratio of the specimens were calculated using the formula: hardness ratio = VK of bottom surface / VK of top surface. For all the materials tested and with all the polymerization modes, hardness ratio was higher than the minimum value indicated in literature in order to consider the bottom surface as adequately cured (0.80). Curing time did not affect hardness ratio values for Filtek Silorane, Grandio and Filtek Supreme XT. The effectiveness of cure at the top and bottom surface was not affected by Soft-start polymerization mode.

  18. Experimental Investigation of Reynolds Number Effects on Test Quality in a Hypersonic Expansion Tube

    NASA Astrophysics Data System (ADS)

    Rossmann, Tobias; Devin, Alyssa; Shi, Wen; Verhoog, Charles

    2017-11-01

    Reynolds number effects on test time and the temporal and spatial flow quality in a hypersonic expansion tube are explored using high-speed pressure, infrared optical, and Schlieren imaging measurements. Boundary layer models for shock tube flows are fairly well established to assist in the determination of test time and flow dimensions at typical high enthalpy test conditions. However, the application of these models needs to be more fully explored due to the unsteady expansion of turbulent boundary layers and contact regions separating dissimilar gasses present in expansion tube flows. Additionally, expansion tubes rely on the development of a steady jet with a large enough core-flow region at the exit of the acceleration tube to create a constant velocity region inside of the test section. High-speed measurements of pressure and Mach number at several locations within the expansion tube allow for the determination of an experimental x-t diagram. The comparison of the experimentally determined x-t diagram to theoretical highlights the Reynolds number dependent effects on expansion tube. Additionally, spatially resolved measurements of the Reynolds number dependent, steady core-flow in the expansion tube viewing section are shown. NSF MRI CBET #1531475, Lafayette College, McCutcheon Foundation.

  19. Effect of Children's Drinks on Color Stability of Different Dental Composites: An in vitro Study.

    PubMed

    Habib, Ahmed Nour El-Din Ahmed; Abdelmoniem, Soad Abdelmoniem; Mahmoud, Sara Ahmed

    To assess the effect of four different children's drinks on color stability of resin dental composites. A total of one hundred and twenty specimens were prepared from Grandio SO, Filtek Z350 XT and Filtek Z250 XT (forty specimens each). Specimens were thermocycled, then each group was further subdivided into four subgroups (n=10) according to the immersion media which were chocolate milk, mango juice, orange fizzy drink, and water (control). The initial color parameters of each specimen were recorded before immersion (baseline) and color change values were recorded three and seven days after immersion in each solution using a digital spectrophotometer. Atomic force microscope was used to measure the surface roughness in randomly selected samples after one week immersion in children's drinks. All the children's drinks produced color changes in the examined resin dental composites, yet there was no statistical significant difference between the effects of tested drinks on the color changes (mean ΔE) of the three different dental composites (P>0.05). All tested children's drinks caused clinically unacceptable color changes of the tested resin dental composites. Immersion in chocolate milk and orange fizzy led to the highest color changes in the tested resin dental composites.

  20. Effect of Quaternary Ammonium Salt on Shear Bond Strength of Orthodontic Brackets to Enamel

    PubMed Central

    Ghadirian, Hannaneh; Geramy, Allahyar; Najafi, Farhood; Heidari, Soolmaz

    2017-01-01

    Objectives: This study sought to assess the effect of quaternary ammonium salt (QAS) on shear bond strength of orthodontic brackets to enamel. Materials and Methods: In this in vitro experimental study, 0, 10, 20 and 30% concentrations of QAS were added to Transbond XT primer. Brackets were bonded to 60 premolar teeth using the afore-mentioned adhesive mixtures, and the shear bond strength of the four groups (n=15) was measured using a universal testing machine. After debonding, the adhesive remnant index (ARI) score was determined under a stereomicroscope. Data were analyzed using one-way ANOVA. Results: The mean and standard deviation of shear bond strength of the control and 10%, 20% and 30% groups were 23.54±6.31, 21.81±2.82, 20.83±8.35 and 22.91±5.66 MPa, respectively. No significant difference was noted in shear bond strength of the groups (P=0.83). Study groups were not different in terms of ARI scores (P=0.80). Conclusions: The results showed that addition of QAS to Transbond XT primer had no adverse effect on shear bond strength of orthodontic brackets. PMID:29167688

  1. Influence of transport and time on blood variables commonly measured for the athlete biological passport.

    PubMed

    Robinson, Neil; Giraud, Sylvain; Schumacher, Yorck Olaf; Saugy, Martial

    2016-02-01

    Some recent studies have characterized the stability of blood variables commonly measured for the Athlete Biological Passport. The aim of this study was to characterize the impact of different shipments conditions and the quality of the results returned by the haematological analyzer. Twenty-two healthy male subjects provided five EDTA tubes each. Four shipment conditions (24, 36, 48, 72 h) under refrigerated conditions were tested and compared to a set of samples left in the laboratory also under refrigerated conditions (group control). All measurements were conducted using two Sysmex XT-2000i analyzers. Haemoglobin concentration, reticulocytes percentage, and OFF-score numerical data were the same for samples analyzed just after collection and after a shipment under refrigerated conditions up to 72 h. Detailed information reported especially by the differential (DIFF) channel scatterplot of the Sysmex XT-2000i indicated that there were signs of blood deterioration, but were not of relevance for the variables used in the Athlete Biological Passport. As long as the cold chain is guaranteed, the time delay between the collection and the analyses of blood variables can be extended. Copyright © 2015 John Wiley & Sons, Ltd.

  2. Investigation of Performance of Axial-Flow Compressor of XT-46 Turbine-Propeller Engine. II - Performance of Revised Compressor at Design Equivalent Speed. II; Performance of Revised Compressor at Design Equivalent Speed

    NASA Technical Reports Server (NTRS)

    Creagh, John W. R.

    1950-01-01

    The compressor from the XT-46 turbine-propeller engine was revised by removing the last two rows of stator blades and by eliminating the interstage leakage paths described in a previous report. With the revised compressor, the flow choking point shifted upstream into the last rotor-blade row but the maximum weight flow was not increased over that of the original compressor. The flow range of the revised compressor was reduced to about two-thirds that obtained with the original compressor. The later stages of the compressor did not produce the design static-pressure increase probably because of excessive boundary-layer build-up in this region. Measurements obtained in the ninth-stage stator showed that the performance up to this station was promising but that the last three stages of the compressor were limiting the useful operating range of the preceding stages. Some modifications in flow-passage geometry and blade settings are believed to be necessary, however, before any major improvements in over-all compressor performance can be obtained.

  3. Efficacy of diode laser (810 and 940 nm) for facial skin tightening.

    PubMed

    Voravutinon, Nataya; Seawthaweesin, Kanikar; Bureethan, Apron; Srivipatana, Anchisa; Vejanurug, Patnapa

    2015-12-01

    Laser treatment has been introduced for facial skin tightening. However, no prior study has used a diode laser to treat facial skin laxity. To evaluate the efficacy and safety of a 810- and 940-nm diode laser (MeDioStarNeXT) for treating facial skin laxity. Thirty patients, with facial skin laxity grading scale II-IV, were enrolled in this study. Each patient underwent four sessions with a 810- and 940-nm diode laser (MeDioStarNeXT) treatment over 3-week intervals. Improvement in the laxity of facial skin was evaluated using a Cutometer MPA 580, spectrophotometer, and a grading scale. Significant improvement was observed with the Cutometer F3 and R7 parameters at 1 and 3 months after complete treatment, respectively. Physician assessment showed significant improvement in the laxity scale at 1 and 6 months after treatment. Approximately 10% of the patients reported mild pain or minor adverse events. Ninety-eight percent of the patients were satisfied with the treatments. Treatment with a diode laser (810 and 940 nm) is safe and may be effective for facial skin tightening. Maintenance treatment is necessary to sustain the effect of treatment. © 2015 Wiley Periodicals, Inc.

  4. Electron stimulated desorption of anions from native and brominated single stranded oligonucleotide trimers

    PubMed Central

    Polska, Katarzyna; Rak, Janusz; Bass, Andrew D.; Cloutier, Pierre; Sanche, Léon

    2013-01-01

    We measured the low energy electron stimulated desorption (ESD) of anions from thin films of native (TXT) and bromine monosubstituted (TBrXT) oligonucleotide trimers deposited on a gold surface (T = thymidine, X = T, deoxycytidine (C), deoxyadenosine (A) or deoxyguanosine (G), Br = bromine). The desorption of H−, CH3−/NH−, O−/NH2−, OH−, CN−, and Br− was induced by 0 to 20 eV electrons. Dissociative electron attachment, below 12 eV, and dipolar dissociation, above 12 eV, are responsible for the formation of these anions. The comparison of the results obtained for the native and brominated trimers suggests that the main pathways of TBrXT degradation correspond to the release of the hydride and bromide anions. Significantly, the presence of bromine in oligonucleotide trimers blocks the electron-induced degradation of nuclobases as evidenced by a dramatic decrease in CN− desorption. An increase in the yields of OH− is also observed. The debromination yield of particular oligonucleotides diminishes in the following order: BrdU > BrdA > BrdG > BrdC. Based on these results, 5-bromo-2′-deoxyuridine appears to be the best radiosensitizer among the studied bromonucleosides. PMID:22360262

  5. Electron stimulated desorption of anions from native and brominated single stranded oligonucleotide trimers.

    PubMed

    Polska, Katarzyna; Rak, Janusz; Bass, Andrew D; Cloutier, Pierre; Sanche, Léon

    2012-02-21

    We measured the low energy electron stimulated desorption (ESD) of anions from thin films of native (TXT) and bromine monosubstituted (TBrXT) oligonucleotide trimers deposited on a gold surface (T = thymidine, X = T, deoxycytidine (C), deoxyadenosine (A) or deoxyguanosine (G), Br = bromine). The desorption of H(-), CH(3)(-)/NH(-), O(-)/NH(2)(-), OH(-), CN(-), and Br(-) was induced by 0 to 20 eV electrons. Dissociative electron attachment, below 12 eV, and dipolar dissociation, above 12 eV, are responsible for the formation of these anions. The comparison of the results obtained for the native and brominated trimers suggests that the main pathways of TBrXT degradation correspond to the release of the hydride and bromide anions. Significantly, the presence of bromine in oligonucleotide trimers blocks the electron-induced degradation of nuclobases as evidenced by a dramatic decrease in CN(-) desorption. An increase in the yields of OH(-) is also observed. The debromination yield of particular oligonucleotides diminishes in the following order: BrdU > BrdA > BrdG > BrdC. Based on these results, 5-bromo-2(')-deoxyuridine appears to be the best radiosensitizer among the studied bromonucleosides. © 2012 American Institute of Physics

  6. Electron stimulated desorption of anions from native and brominated single stranded oligonucleotide trimers

    NASA Astrophysics Data System (ADS)

    Polska, Katarzyna; Rak, Janusz; Bass, Andrew D.; Cloutier, Pierre; Sanche, Léon

    2012-02-01

    We measured the low energy electron stimulated desorption (ESD) of anions from thin films of native (TXT) and bromine monosubstituted (TBrXT) oligonucleotide trimers deposited on a gold surface (T = thymidine, X = T, deoxycytidine (C), deoxyadenosine (A) or deoxyguanosine (G), Br = bromine). The desorption of H-, CH3-/NH-, O-/NH2-, OH-, CN-, and Br- was induced by 0 to 20 eV electrons. Dissociative electron attachment, below 12 eV, and dipolar dissociation, above 12 eV, are responsible for the formation of these anions. The comparison of the results obtained for the native and brominated trimers suggests that the main pathways of TBrXT degradation correspond to the release of the hydride and bromide anions. Significantly, the presence of bromine in oligonucleotide trimers blocks the electron-induced degradation of nuclobases as evidenced by a dramatic decrease in CN- desorption. An increase in the yields of OH- is also observed. The debromination yield of particular oligonucleotides diminishes in the following order: BrdU > BrdA > BrdG > BrdC. Based on these results, 5-bromo-2'-deoxyuridine appears to be the best radiosensitizer among the studied bromonucleosides.

  7. Diversity of Group I and II Clostridium botulinum Strains from France Including Recently Identified Subtypes.

    PubMed

    Mazuet, Christelle; Legeay, Christine; Sautereau, Jean; Ma, Laurence; Bouchier, Christiane; Bouvet, Philippe; Popoff, Michel R

    2016-06-13

    In France, human botulism is mainly food-borne intoxication, whereas infant botulism is rare. A total of 99 group I and II Clostridium botulinum strains including 59 type A (12 historical isolates [1947-1961], 43 from France [1986-2013], 3 from other countries, and 1 collection strain), 31 type B (3 historical, 23 recent isolates, 4 from other countries, and 1 collection strain), and 9 type E (5 historical, 3 isolates, and 1 collection strain) were investigated by botulinum locus gene sequencing and multilocus sequence typing analysis. Historical C. botulinum A strains mainly belonged to subtype A1 and sequence type (ST) 1, whereas recent strains exhibited a wide genetic diversity: subtype A1 in orfX or ha locus, A1(B), A1(F), A2, A2b2, A5(B2') A5(B3'), as well as the recently identified A7 and A8 subtypes, and were distributed into 25 STs. Clostridium botulinum A1(B) was the most frequent subtype from food-borne botulism and food. Group I C. botulinum type B in France were mainly subtype B2 (14 out of 20 historical and recent strains) and were divided into 19 STs. Food-borne botulism resulting from ham consumption during the recent period was due to group II C. botulinum B4. Type E botulism is rare in France, 5 historical and 1 recent strains were subtype E3. A subtype E12 was recently identified from an unusual ham contamination. Clostridium botulinum strains from human botulism in France showed a wide genetic diversity and seems to result not from a single evolutionary lineage but from multiple and independent genetic rearrangements. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  8. A multiplex reverse transcription-nested polymerase chain reaction for detection and differentiation of wild-type and vaccine strains of canine distemper virus

    PubMed Central

    2010-01-01

    A multiplex reverse transcription-nested polymerase chain reaction (RT-nPCR) method was developed for the detection and differentiation of wild-type and vaccine strains of canine distemper virus (CDV). A pair of primers (P1 and P4) specific for CDV corresponding to the highly conserved region of the CDV genome were used as a common primer pair in the first-round PCR of the nested PCR. Primers P2 specific for CDV wild-type strains, were used as the forward primer together with the common reverse primer P4 in the second round of nested PCR. Primers P3, P5 specific for CDV wild-type strain or vaccine strain, were used as the forward primer together with the common reverse primer P4+P6 in the second round of nested PCR. A fragment of 177 bp was amplified from vaccine strain genomic RNA, and a fragment of 247 bp from wild-type strain genomic RNA in the RT-nPCR, and two fragments of 247 bp and 177 bp were amplified from the mixed samples of vaccine and wild-type strains. No amplification was achieved for uninfected cells, or cells infected with Newcastle disease virus (NDV), canine parvovirus (CPV), canine coronavirus (CCV), rabies virus (RV), or canine adenovirus (CAV). The RT-nPCR method was used to detect 30 field samples suspected of canine distemper from Heilongjiang and Jilin Provinces, and 51 samples in Shandong province. As a result of 30 samples, were found to be wild-type-like, and 5 to be vaccine-strain-like. The RT-nPCR method can be used to effectively detect and differentiate wild-type CDV-infected dogs from dogs vaccinated with CDV vaccine, and thus can be used in clinical detection and epidemiological surveillance. PMID:20433759

  9. Genotyping of Yersinia enterocolitica biotype 1A strains from clinical and nonclinical origins by pulsed-field gel electrophoresis.

    PubMed

    Campioni, Fábio; Falcão, Juliana P

    2014-06-01

    Yersinia enterocolitica biotype 1A (B1A) strains are considered mainly nonpathogenic. However, some studies considered strains of this biotype to be the causal agents of infections in humans and animals. In South America, there are no studies that have compared clinical and nonclinical strains of B1A typed by pulsed-field gel electrophoresis (PFGE) and none that have compared the capability of different enzymes on typing these strains. This study typed 51 Y. enterocolitica B1A strains isolated in Brazil and Chile by PFGE, testing the enzymes XbaI, NotI, and XhoI. The resulting dendrograms discriminated the strains in 47, 40, and 49 pulsotypes generated by the cleavage with the enzymes XbaI, NotI, and XhoI, respectively. The majority of the strains were grouped independently of their clinical or nonclinical origins. The high discriminatory power of PFGE confirmed the heterogeneity of B1A strains but could not divide the strains studied into clusters that differed in the frequency of some virulence genes as observed in studies using other methodologies.

  10. A critical re-evaluation of multilocus sequence typing (MLST) efforts in Wolbachia.

    PubMed

    Bleidorn, Christoph; Gerth, Michael

    2018-01-01

    Wolbachia (Alphaproteobacteria, Rickettsiales) is the most common, and arguably one of the most important inherited symbionts. Molecular differentiation of Wolbachia strains is routinely performed with a set of five multilocus sequence typing (MLST) markers. However, since its inception in 2006, the performance of MLST in Wolbachia strain typing has not been assessed objectively. Here, we evaluate the properties of Wolbachia MLST markers and compare it to 252 other single copy loci present in the genome of most Wolbachia strains. Specifically, we investigated how well MLST performs at strain differentiation, at reflecting genetic diversity of strains, and as phylogenetic marker. We find that MLST loci are outperformed by other loci at all tasks they are currently employed for, and thus that they do not reflect the properties of a Wolbachia strain very well. We argue that whole genome typing approaches should be used for Wolbachia typing in the future. Alternatively, if few loci approaches are necessary, we provide a characterisation of 252 single copy loci for a number a criteria, which may assist in designing specific typing systems or phylogenetic studies. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. High genotypic and phenotypic similarity among Shiga toxin-producing Escherichia coli O111 environmental and outbreak strains.

    PubMed

    Diodati, Michelle E; Bates, Anne H; Cooley, Michael B; Walker, Samarpita; Mandrell, Robert E; Brandl, Maria T

    2015-03-01

    Escherichia coli serogroup O111 is among the six most commonly reported non-O157:H7 Shiga toxin-producing E. coli (STEC), which are emerging as important foodborne pathogens. We have assembled a collection of environmental and clinical strains of E. coli O111 from diverse sources and investigated various genotypic and phenotypic characteristics of these strains to gain a better understanding of the epidemiology and biology of this serogroup. Sixty-three percent of the strains (24/38) were of H-type 8, which dominated the environmental- and outbreak-strains group, whereas the sporadic-case strains were more heterogeneous in H-type. All of the environmental and outbreak strains harbored the Shiga toxin 1 gene (stx1), eae, and ehx, and a subset of these also carried the Shiga toxin 2 gene (stx2). Only 9 of 16 sporadic-case strains produced stx1 and/or stx2, and these were mostly of H-type 8 and 10. Pulsed-field gel electrophoresis analysis revealed a cluster of environmental, outbreak, and sporadic illness strains with high phylogenetic similarity. Strains in this pulsogroup were all of the H8 type and STEC pathotype, and carried eae and ehx. Smaller clusters of highly similar STEC O111 strains included outbreak and sporadic illness strains isolated during different time periods or from different geographical locations. A distinct aggregative behavior was observed in the cultures of all environmental and outbreak STEC O111 strains, but not in those of sporadic-case strains. Among environmental and outbreaks strains, aggregation was positively correlated with production of curli fimbriae and RpoS function, and negatively with cellulose synthesis, while the nonaggregative behavior of sporadic-case strains correlated (positively) only with cellulose production. Our results indicate that STEC O111 strains sharing high genotypic similarity and important phenotypic traits with STEC O111 outbreak strains are present in the agricultural environment and may contribute to the burden of foodborne disease.

  12. Comparison of hemagglutinating, receptor-destroying, and acetylesterase activities of avirulent and virulent bovine coronavirus strains.

    PubMed

    Storz, J; Zhang, X M; Rott, R

    1992-01-01

    Hemagglutinating and acetylesterase functions as well as the 124 kDa glycoprotein were present in the highly cell-culture adapted, avirulent bovine coronavirus strain BCV-L9, in the Norden vaccine strain derived from it, and in 5 wild-type, virulent strains that multiplied in HRT-18 cells but were restricted in several types of cultured bovine cells. The BCV-L9 and the wild-type strain BCV-LY-138 agglutinated chicken and mouse erythrocytes. The acetylesterase facilitated break-down of the BCV-erythrocyte complex with chicken but only to a minimal extent with mouse erythrocytes in the receptor-destroying enzyme test. Purified preparations of the vaccine and the wild-type strains agglutinated chicken erythrocytes at low titers and mouse erythrocytes at 128 to 256 times higher titers whereas receptor destroying enzyme activity was detectable only with chicken erythrocytes. When wild-type strains were propagated in HRT cells at low passage levels, they produced 5 x 10(5) to 4.5 x 10(6) plaque forming units per 50 microliters which agglutinated erythrocytes from mice but not from chickens. Diisopropylfluoro-phosphate moderately increased the hemagglutination titers, but completely inhibited the receptor destroying enzyme of purified virus of all strains. It had virtually no influence on the plaque-forming infectivity of the different BCV strains. The acetylesterase of strain BCV-L9 reacting in the receptor-destroying enzyme test was stable for 3 h at 37 and 42 degrees C. It was inactivated within 30 min at 56 degrees C while the hemagglutinin function of this strain was stable for 3 h at 37, 42, and 56 degrees C, but it was inactivated at 65 degrees C within 1 h.

  13. Genetics of Ustilago violacea. XXXII. Genetic evidence for transposable elements.

    PubMed

    Garber, E D; Ruddat, M

    1994-12-01

    Crosses between Ustilago violacea mutant strains with different color phenotypes that were derived from the 1.A1 and 2.A2 laboratory strains yielded, as expected, bisectored teliospore colonies with the parental colors as well as the a-1 and the a-2 mating-types. Generally, wild teliospore collections usually produced sporidia of both mating-types, providing two-mating-type (TMT) strains. Occasionally, however, sporidia with only one mating-type allele, a-1 or a-2, were obtained from teliospores, providing one-mating-type (OMT) strains. Crosses between OMT and laboratory strains with different color phenotypes gave (1) bisectored teliospore colonies with the parental colors or colonies with a parental color and a nonparental color and (2) nonsectored colonies with the nonparental color or with the parental color. The frequencies for the occurrence of non-parental color ranged from 41% to 93%, depending on the strain. The yield of teliospore colonies was usually reduced for these crosses. In many of these teliospore colonies, morphologically-altered sporidia (MAS phenotype) were observed. The morphology and the size of the sporidia with the MAS phenotype differed from those of teliospore colonies of the crosses between the laboratory strains. In addition, these sporidia did not form conjugants. A cross involving the TMT strains C449 yielded the MAS phenotype as well as a high incidence of tetrad colonies with a nonparental color. The high degree of instability of the parental color phenotypes, and the high frequency of the appearance of nonparental color phenotypes as well as the appearance of the MAS phenotype, are in accord with the presence of active and inactive transposable elements in the OMT strains, TMT strains, and laboratory strains.

  14. Application of protein typing in molecular epidemiological investigation of nosocomial infection outbreak of aminoglycoside-resistant Pseudomonas aeruginosa.

    PubMed

    Song, Min; Tang, Min; Ding, Yinghuan; Wu, Zecai; Xiang, Chengyu; Yang, Kui; Zhang, Zhang; Li, Baolin; Deng, Zhenghua; Liu, Jinbo

    2017-12-16

    Pseudomonas aeruginosan has emerged as an important pathogen elated to serious infections and nosocomial outbreaks worldwide. This study was conducted to understand the prevalence of aminoglycoside (AMG)-resistant P. aeruginosa in our hospital and to provide a scientific basis for control measures against nosocomial infections. Eighty-two strains of P. aeruginosa were isolated from clinical departments and divided into AMG-resistant strains and AMG-sensitive strains based on susceptibility test results. AMG-resistant strains were typed by drug resistance gene typing (DRGT) and protein typing. Five kinds of aminoglycoside-modifying enzyme (AME) genes were detected in the AMG-resistant group. AMG-resistant P. aeruginosa strains were classified into three types and six subtypes by DRGT. Four protein peaks, namely, 9900.02, 7600.04, 9101.25 and 10,372.87 Da, were significantly and differentially expressed between the two groups. AMG-resistant P. aeruginosa strains were also categorised into three types and six subtypes at the distance level of 10 by protein typing. AMG-resistant P. aeruginosa was cloned spread in our hospital; the timely implementation of nosocomial infection prevention and control strategies were needed in preventing outbreaks and epidemic of AMG-resistant P. aeruginosa. SELDI-TOF MS technology can be used for bacterial typing, which provides a new method of clinical epidemiological survey and nosocomial infection control.

  15. Escherichia coli H-Genotyping PCR: a Complete and Practical Platform for Molecular H Typing.

    PubMed

    Banjo, Masaya; Iguchi, Atsushi; Seto, Kazuko; Kikuchi, Taisei; Harada, Tetsuya; Scheutz, Flemming; Iyoda, Sunao

    2018-06-01

    In Escherichia coli , more than 180 O groups and 53 H types have been recognized. The O:H serotyping of E. coli strains is an effective method for identifying strains with pathogenic potential and classifying them into clonal groups. In particular, the serotyping of Shiga toxin-producing E. coli (STEC) strains provides valuable information to evaluate the routes, sources, and prevalence of agents in outbreak investigations and surveillance. Here, we present a complete and practical PCR-based H-typing system, E. coli H-genotyping PCR, consisting of 10 multiplex PCR kits with 51 single PCR primer pairs. Primers were designed based on a detailed comparative analysis of sequences from all H-antigen (flagellin)-encoding genes, fliC and its homologs. The specificity of this system was confirmed by using all H type reference strains. Additionally, 362 serotyped wild strains were also used to evaluate its practicality. All 277 H-type-identified isolates gave PCR products that corresponded to the results of serological H typing. Moreover, 76 nonmotile and nine untypeable strains could be successfully subtyped into any H type by the PCR system. The E. coli H-genotyping PCR developed here allows broader, rapid, and low-cost subtyping of H types and will assist epidemiological studies as well as surveillance of pathogenic E. coli . Copyright © 2018 American Society for Microbiology.

  16. Genome Sequence of the Thermophile Bacillus coagulans Hammer, the Type Strain of the Species

    PubMed Central

    Su, Fei; Tao, Fei; Tang, Hongzhi

    2012-01-01

    Here we announce a 3.0-Mb assembly of the Bacillus coagulans Hammer strain, which is the type strain of the species within the genus Bacillus. Genomic analyses based on the sequence may provide insights into the phylogeny of the species and help to elucidate characteristics of the poorly studied strains of Bacillus coagulans. PMID:23105047

  17. Genome sequence of the thermophile Bacillus coagulans Hammer, the type strain of the species.

    PubMed

    Su, Fei; Tao, Fei; Tang, Hongzhi; Xu, Ping

    2012-11-01

    Here we announce a 3.0-Mb assembly of the Bacillus coagulans Hammer strain, which is the type strain of the species within the genus Bacillus. Genomic analyses based on the sequence may provide insights into the phylogeny of the species and help to elucidate characteristics of the poorly studied strains of Bacillus coagulans.

  18. Virulence type and tissue tropism of Staphylococcus strains originating from Hungarian rabbit farms.

    PubMed

    Német, Zoltán; Albert, Ervin; Nagy, Krisztina; Csuka, Edit; Dán, Ádám; Szenci, Ottó; Hermans, Katleen; Balka, Gyula; Biksi, Imre

    2016-09-25

    Staphylococcosis has a major economic impact on rabbit farming worldwide. Previous studies described a highly virulent variant, which is disseminated across Europe. Such strains are reported to be capable of inducing uncontrollable outbreaks. The authors describe a survey conducted on 374 Staphylococcus strains isolated from rabbit farms, mostly from Hungary, between 2009 and 2014, from a variety of pathological processes. The virulence type of the strains was determined using a multiplex PCR system. 84.2% of the strains belonged to a previously rarely isolated atypical highly virulent type. Only 6.1% belonged to the typical highly virulent genotype. Even low virulent strains were present at a higher percentage (6.4%). For a small group of strains (3.2%) the detection of the femA gene failed, indicating that these strains probably do not belong to the Staphylococcus aureus species. The results reveal the possibility of the asymptomatic presence of highly virulent strains on rabbit farms. "Non-aureus" Staphylococcus sp. can also have a notable role in the etiology of rabbit staphylococcosis. An association with the lesions and the virulence type was demonstrated. Statistical analysis of data on organotropism showed a significant correlation between septicaemia and the highly virulent genotype. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Genetic diversity analysis of Leuconostoc mesenteroides from Korean vegetables and food products by multilocus sequence typing.

    PubMed

    Sharma, Anshul; Kaur, Jasmine; Lee, Sulhee; Park, Young-Seo

    2018-06-01

    In the present study, 35 Leuconostoc mesenteroides strains isolated from vegetables and food products from South Korea were studied by multilocus sequence typing (MLST) of seven housekeeping genes (atpA, groEL, gyrB, pheS, pyrG, rpoA, and uvrC). The fragment sizes of the seven amplified housekeeping genes ranged in length from 366 to 1414 bp. Sequence analysis indicated 27 different sequence types (STs) with 25 of them being represented by a single strain indicating high genetic diversity, whereas the remaining 2 were characterized by five strains each. In total, 220 polymorphic nucleotide sites were detected among seven housekeeping genes. The phylogenetic analysis based on the STs of the seven loci indicated that the 35 strains belonged to two major groups, A (28 strains) and B (7 strains). Split decomposition analysis showed that intraspecies recombination played a role in generating diversity among strains. The minimum spanning tree showed that the evolution of the STs was not correlated with food source. This study signifies that the multilocus sequence typing is a valuable tool to access the genetic diversity among L. mesenteroides strains from South Korea and can be used further to monitor the evolutionary changes.

  20. Strain hypothesis of Toxoplasma gondii infection on the outcome of human diseases

    PubMed Central

    Xiao, Jianchun; Yolken, Robert H.

    2015-01-01

    The intracellular protozoan Toxoplasma gondii is an exceptionally successful food- and waterborne parasite that infects approximately 1 billion people worldwide. Genotyping of T. gondii isolates from all continents revealed a complex population structure. Recent research supports the notion that T. gondii genotype may be associated with disease severity. Here, we (1) discuss molecular and serological approaches for designation of T. gondii strain type, (2) overview the literatures on the association of T. gondii strain type and the outcome of human disease, and (3) explore possible mechanisms underlying these strain specific pathology and severity of human toxoplasmosis. Although no final conclusions can be drawn, it is clear that virulent strains (e. g. strains containing type I or atypical alleles) are significantly more often associated with increased frequency and severity of human toxoplasmosis. The significance of highly virulent strains can cause severe diseases in immunocompetent patients and might implicated in brain disorders such as schizophrenia should led to reconsideration of toxoplasmosis. Further studies that combine parasite strain typing and human factor analysis (e.g. immune status and genetic background) are required for better understanding of human susceptibility or resistance to toxoplasmosis. PMID:25600911

  1. Comparative characteristics of the VP7 and VP4 antigenic epitopes of the rotaviruses circulating in Russia (Nizhny Novgorod) and the Rotarix and RotaTeq vaccines.

    PubMed

    Morozova, O V; Sashina, T A; Fomina, S G; Novikova, N A

    2015-07-01

    Two live, attenuated rotavirus A (RVA) vaccines, Rotarix and RotaTeq, have been successfully introduced into national immunization programs worldwide. The parent strains of both vaccines were obtained more than 30 years ago. Nonetheless, only very limited data are available on the molecular similarity of the vaccine strains and their genetic relationships to the wild-type strains circulating within the territory of Russian Federation. In this study, we have determined the nucleotide sequences of the genes encoding the viral proteins VP7 and VP4 (the globular domain VP8*) of vaccine strains and natural isolates of rotaviruses in Nizhny Novgorod, Russia. The VP7 and VP4 proteins contain antigenic sites that are the main targets of neutralizing antibodies. Phylogenetic analysis based on VP4 and VP7 showed that the majority of the natural RVA isolates from Nizhny Novgorod and the vaccine strains belong to different clusters. Four amino acids within the VP7 antigenic sites were common in both the wild-type and vaccine strains. The largest number of amino acid differences was found between the vaccine strain Rotarix and the Nizhny Novgorod G2 strains (19 residues out of 29). From 3 to 5 amino acid differences per strain were identified in the antigenic sites of VP4 (domain VP8*) between wild-type strains and the vaccine RotaTeq, and 6-8 substitutions were found when they were compared with the vaccine strain Rotarix. For the first time, immunodominant T-cell epitopes of VP7 were analyzed, and differences in the sequences between the vaccine and the wild-type strains were found. The accumulation of amino acid substitutions in the VP7 and VP4 antigenic sites may potentially reduce the immune protection of vaccinated children from wild-type strains of rotavirus.

  2. Prevalence of toxoplasmosis and genetic characterization of Toxoplasma gondii strains isolated in wild birds of prey and their relation with previously isolated strains from Turkey.

    PubMed

    Karakavuk, Muhammet; Aldemir, Duygu; Mercier, Aurélien; Atalay Şahar, Esra; Can, Hüseyin; Murat, Jean-Benjamin; Döndüren, Ömer; Can, Şengül; Özdemir, Hüseyin Gökhan; Değirmenci Döşkaya, Aysu; Pektaş, Bayram; Dardé, Marie-Laure; Gürüz, Adnan Yüksel; Döşkaya, Mert

    2018-01-01

    Toxoplasma gondii is a protozoon parasite that causes congenital toxoplasmosis, as well as other serious clinical presentations, in immune compromised humans. Analyses of the prevalence and genotyping of strains from the definitive host and intermediate hosts will help to understanding the circulation of the different strains and elucidating the role of the genotype(s) in human toxoplasmosis. Turkey has a specific geographic location bridging Africa, Europe, and Asia. We hypothesized that T. gondii strains may have been transferred to Turkey from these continents via migratory birds or vice versa. The present study aimed to assess the prevalence of toxoplasmosis in wild birds of prey of İzmir and Manisa provinces as well as genetically characterize T. gondii strains from these wild birds to show the relation between bird strains and neighboring stray cats as well as human strains previously isolated in Turkey. Tissues obtained from 48 wild birds were investigated for the presence of T. gondii DNA and then bioassayed in mouse. Isolated strains were genotyped using 15 microsatellite markers. The prevalence of T. gondii DNA was found to be 89.6% (n: 43/48) in wild birds. Out of 43 positive samples, a total of 14 strains were genotyped by 15 microsatellite markers. Among them, eight were type II, three were type III and three were mixture of genotypes (two type II/II and one was II/III). These are the first data that showed the presence of T. gondii and types II and III genotypes in wild birds of Turkey. Moreover, Africa 1 was not detected. In addition, cluster analysis showed that T. gondii strains within type II and III lineage have close relation with strains previously isolated from stray cats in İzmir. Further studies are required to isolate more strains from human cases, other intermediate hosts, and water sources to reveal this relation.

  3. Prevalence of toxoplasmosis and genetic characterization of Toxoplasma gondii strains isolated in wild birds of prey and their relation with previously isolated strains from Turkey

    PubMed Central

    Karakavuk, Muhammet; Aldemir, Duygu; Mercier, Aurélien; Atalay Şahar, Esra; Can, Hüseyin; Murat, Jean-Benjamin; Döndüren, Ömer; Can, Şengül; Özdemir, Hüseyin Gökhan; Değirmenci Döşkaya, Aysu; Pektaş, Bayram; Dardé, Marie-Laure; Gürüz, Adnan Yüksel

    2018-01-01

    Toxoplasma gondii is a protozoon parasite that causes congenital toxoplasmosis, as well as other serious clinical presentations, in immune compromised humans. Analyses of the prevalence and genotyping of strains from the definitive host and intermediate hosts will help to understanding the circulation of the different strains and elucidating the role of the genotype(s) in human toxoplasmosis. Turkey has a specific geographic location bridging Africa, Europe, and Asia. We hypothesized that T. gondii strains may have been transferred to Turkey from these continents via migratory birds or vice versa. The present study aimed to assess the prevalence of toxoplasmosis in wild birds of prey of İzmir and Manisa provinces as well as genetically characterize T. gondii strains from these wild birds to show the relation between bird strains and neighboring stray cats as well as human strains previously isolated in Turkey. Tissues obtained from 48 wild birds were investigated for the presence of T. gondii DNA and then bioassayed in mouse. Isolated strains were genotyped using 15 microsatellite markers. The prevalence of T. gondii DNA was found to be 89.6% (n: 43/48) in wild birds. Out of 43 positive samples, a total of 14 strains were genotyped by 15 microsatellite markers. Among them, eight were type II, three were type III and three were mixture of genotypes (two type II/II and one was II/III). These are the first data that showed the presence of T. gondii and types II and III genotypes in wild birds of Turkey. Moreover, Africa 1 was not detected. In addition, cluster analysis showed that T. gondii strains within type II and III lineage have close relation with strains previously isolated from stray cats in İzmir. Further studies are required to isolate more strains from human cases, other intermediate hosts, and water sources to reveal this relation. PMID:29668747

  4. Full-length genome sequence analysis of four subgroup J avian leukosis virus strains isolated from chickens with clinical hemangioma.

    PubMed

    Lin, Lulu; Wang, Peikun; Yang, Yongli; Li, Haijuan; Huang, Teng; Wei, Ping

    2017-12-01

    Since 2014, cases of hemangioma associated with avian leukosis virus subgroup J (ALV-J) have been emerging in commercial chickens in Guangxi. In this study, four strains of the subgroup J avian leukosis virus (ALV-J), named GX14HG01, GX14HG04, GX14LT07, and GX14ZS14, were isolated from chickens with clinical hemangioma in 2014 by DF-1 cell culture and then identified with ELISA detection of ALV group specific antigen p27, the detection of subtype specific PCR and indirect immunofluorescence assay (IFA) with ALV-J specific monoclonal antibody. The complete genomes of the isolates were sequenced and it was found that the gag and pol were relatively conservative, while env was variable especially the gp85 gene. Homology analysis of the env gene sequences showed that the env gene of all the four isolates had higher similarities with the hemangioma (HE)-type reference strains than that of the myeloid leukosis (ML)-type strains, and moreover, the HE-type strains' specific deletion of 205-bp sequence covering the rTM and DR1 in 3'UTR fragment was also found in the four isolates. Further analysis on the sequences of subunits of env gene revealed an interesting finding: the gp85 of isolates GX14ZS14 and GX14HG04 had a higher similarity with HPRS-103 and much lower similarity with the HE-type reference strains resulting in GX14ZS14, GX14HG04, and HPRS-103 being clustered in the same branch, while gp37 had higher similarities with the HE-type reference strains when compared to that of HPRS-103, resulted in GX14ZS14, GX14HG04, and HE-type reference strains being clustered in the same branch. The results suggested that isolates GX14ZS14 and GX14HG04 may be the recombinant strains of the foreign strain HPRS-103 with the local epidemic HE-type strains of ALV-J.

  5. How to find future ecstasy-users: targeted and snowball sampling in an ethically sensitive context.

    PubMed

    Vervaeke, Hylke K E; Korf, Dirk J; Benschop, Annemieke; van den Brink, Wim

    2007-08-01

    This article documents the design and the sampling procedures of a prospective longitudinal multidisciplinary study on the neurotoxicity of ecstasy (MDMA): the Netherlands XTC Toxicity Study (NeXT). Targeted and snowball sampling was used to recruit 188 respondents who were ecstasy-naive at baseline. All respondents completed baseline questionnaires and underwent medical and neuropsychological examinations. At the end of a 11- to 26- month follow-up period in which they completed four additional questionnaires, 160 respondents remained (85.1%). A total of 65 participants (40.6%) took ecstasy for the first time during the follow-up period. This paper discusses the ethical dilemmas inherent in a study of this type and the specific problems and solutions that emerged in the sampling. The sampling was tightly constrained by our need to locate respondents who were potential future ecstasy users while also meeting strict medical and technical criteria. The 'intention to use' criterion proved to be a clear-cut inclusion rule that was practical to apply in the fieldwork.

  6. Molecular Markers to Detect the Formation of Heterokaryon and Homokaryon from Asexual Spores of the Caterpillar Medicinal Mushroom, Cordyceps militaris (Ascomycetes).

    PubMed

    Wang, Hong; Cai, Tao; Wei, Jing; Feng, Aiping; Lin, Nan; Bao, Dapeng

    2015-01-01

    Cordyceps militaris is widely cultivated on artificial media in China; however, the cultures often are afflicted with the degeneration of nonfruiting strains. To understand the mechanism of degeneration of C. militaris, from the heterokaryotic strain into the homokaryotic strain, we examined the mating-type genes present in individual asexual spores. Further, we determined the distribution ratio of the different mating-type genes among a sample of asexual spores and the growth rate of heterokaryotic and homokaryotic strains of C. militaris. The distribution ratio of 3 groups of asexual spores from C. militaris heterokaryotic strains was determined as 1:1:1 by statistical analysis, whereas that of the two types of nuclei among asexual spores was 1:1. Nearly two-thirds of the asexual spore isolates were homokaryon, which showed a growth speed similar to the heterokaryon. However, the homokaryon (bearing mating-type MAT-HMG) grew significantly faster at times compared with the heterokaryon. Therefore, the purity of the spawn was difficult to establish. C. militaris heterokaryotic strains can transform into a homokaryotic strain following continued subculture.

  7. Clonal Relatedness of Enterotoxigenic Escherichia coli (ETEC) Strains Expressing LT and CS17 Isolated from Children with Diarrhoea in La Paz, Bolivia

    PubMed Central

    Rodas, Claudia; Klena, John D.; Nicklasson, Matilda; Iniguez, Volga; Sjöling, Åsa

    2011-01-01

    Background Enterotoxigenic Escherichia coli (ETEC) is a major cause of traveller's and infantile diarrhoea in the developing world. ETEC produces two toxins, a heat-stable toxin (known as ST) and a heat-labile toxin (LT) and colonization factors that help the bacteria to attach to epithelial cells. Methodology/Principal Findings In this study, we characterized a subset of ETEC clinical isolates recovered from Bolivian children under 5 years of age using a combination of multilocus sequence typing (MLST) analysis, virulence typing, serotyping and antimicrobial resistance test patterns in order to determine the genetic background of ETEC strains circulating in Bolivia. We found that strains expressing the heat-labile (LT) enterotoxin and colonization factor CS17 were common and belonged to several MLST sequence types but mainly to sequence type-423 and sequence type-443 (Achtman scheme). To further study the LT/CS17 strains we analysed the nucleotide sequence of the CS17 operon and compared the structure to LT/CS17 ETEC isolates from Bangladesh. Sequence analysis confirmed that all sequence type-423 strains from Bolivia had a single nucleotide polymorphism; SNPbol in the CS17 operon that was also found in some other MLST sequence types from Bolivia but not in strains recovered from Bangladeshi children. The dominant ETEC clone in Bolivia (sequence type-423/SNPbol) was found to persist over multiple years and was associated with severe diarrhoea but these strains were variable with respect to antimicrobial resistance patterns. Conclusion/Significance The results showed that although the LT/CS17 phenotype is common among ETEC strains in Bolivia, multiple clones, as determined by unique MLST sequence types, populate this phenotype. Our data also appear to suggest that acquisition and loss of antimicrobial resistance in LT-expressing CS17 ETEC clones is more dynamic than acquisition or loss of virulence factors. PMID:22140423

  8. Clonal relatedness of enterotoxigenic Escherichia coli (ETEC) strains expressing LT and CS17 isolated from children with diarrhoea in La Paz, Bolivia.

    PubMed

    Rodas, Claudia; Klena, John D; Nicklasson, Matilda; Iniguez, Volga; Sjöling, Asa

    2011-01-01

    Enterotoxigenic Escherichia coli (ETEC) is a major cause of traveller's and infantile diarrhoea in the developing world. ETEC produces two toxins, a heat-stable toxin (known as ST) and a heat-labile toxin (LT) and colonization factors that help the bacteria to attach to epithelial cells. In this study, we characterized a subset of ETEC clinical isolates recovered from Bolivian children under 5 years of age using a combination of multilocus sequence typing (MLST) analysis, virulence typing, serotyping and antimicrobial resistance test patterns in order to determine the genetic background of ETEC strains circulating in Bolivia. We found that strains expressing the heat-labile (LT) enterotoxin and colonization factor CS17 were common and belonged to several MLST sequence types but mainly to sequence type-423 and sequence type-443 (Achtman scheme). To further study the LT/CS17 strains we analysed the nucleotide sequence of the CS17 operon and compared the structure to LT/CS17 ETEC isolates from Bangladesh. Sequence analysis confirmed that all sequence type-423 strains from Bolivia had a single nucleotide polymorphism; SNP(bol) in the CS17 operon that was also found in some other MLST sequence types from Bolivia but not in strains recovered from Bangladeshi children. The dominant ETEC clone in Bolivia (sequence type-423/SNP(bol)) was found to persist over multiple years and was associated with severe diarrhoea but these strains were variable with respect to antimicrobial resistance patterns. The results showed that although the LT/CS17 phenotype is common among ETEC strains in Bolivia, multiple clones, as determined by unique MLST sequence types, populate this phenotype. Our data also appear to suggest that acquisition and loss of antimicrobial resistance in LT-expressing CS17 ETEC clones is more dynamic than acquisition or loss of virulence factors.

  9. Molecular and phenotypic analyses reveal the non-identity of the Phaeobacter gallaeciensis type strain deposits CIP 105210T and DSM 17395.

    PubMed

    Buddruhs, Nora; Pradella, Silke; Göker, Markus; Päuker, Orsola; Pukall, Rüdiger; Spröer, Cathrin; Schumann, Peter; Petersen, Jörn; Brinkhoff, Thorsten

    2013-11-01

    The marine genus Phaeobacter currently comprises six species, some of which were intensively studied mainly due to their ability to produce secondary metabolites. The type strain of the type species, Phaeobacter gallaeciensis BS107(T), has been deposited at several public culture collections worldwide. Based on differences in plasmid profiles, we detected that the alleged P. gallaeciensis type strains deposited at the Collection Institute Pasteur (CIP; Paris, France) as CIP 105210 and at the German Collection of Microorganisms and Cell Cultures (DSMZ; Braunschweig, Germany) as DSM 17395 are not identical. To determine the identity of these strains, we conducted DNA-DNA hybridization, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF), 16S rRNA gene and internal transcribed spacer (ITS) sequence analyses, as well as physiological experiments. Based on the detailed 16S rRNA gene reanalysis we showed that strain CIP 105210 most likely corresponds to the original P. gallaeciensis type strain BS107(T). In contrast, the Phaeobacter strain DSM 17395 exhibits a much closer affiliation to Phaeobacter inhibens DSM 16374(T) ( = T5(T)) and should thus be allocated to this species. The detection of the dissimilarity of strains CIP 105210(T) and DSM 17395 will influence future comparative studies within the genus Phaeobacter.

  10. Comparison of four molecular methods to type Salmonella Enteritidis strains.

    PubMed

    Campioni, Fábio; Pitondo-Silva, André; Bergamini, Alzira M M; Falcão, Juliana P

    2015-05-01

    This study compared the pulsed-field gel electrophoresis (PFGE), enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR), multilocus variable-number of tanden-repeat analysis (MLVA), and multilocus sequence typing (MLST) methods for typing 188 Salmonella Enteritidis strains from different sources isolated over a 24-year period in Brazil. PFGE and ERIC-PCR were more efficient than MLVA for subtyping the strains. However, MLVA provided additional epidemiological information for those strains. In addition, MLST showed the Brazilian strains as belonging to the main clonal complex of S. Enteritidis, CC11, and provided the first report of two new STs in the S. enterica database but could not properly subtype the strains. Our results showed that the use of PFGE or ERIC-PCR together with MLVA is suitable to efficiently subtype S. Enteritidis strains and provide important epidemiological information. © 2015 APMIS. Published by John Wiley & Sons Ltd.

  11. Nonalcoholic Fatty Liver Is Associated With Further Left Ventricular Abnormalities in Patients With Type 2 Diabetes Mellitus: A 3-Dimensional Speckle-Tracking Study.

    PubMed

    Wang, Qingqing; Ma, Wenyan; Xia, Jizhu

    2018-01-24

    The aim of this study was to detect left ventricular (LV) structure and function abnormalities in patients with type 2 diabetes mellitus with or without nonalcoholic fatty liver (NAFL) using 3-dimensional speckle-tracking echocardiography. Eighty patients with type 2 diabetes and a normal LV ejection fraction (≥55%), including 40 with coexistent NAFL, and 40 age- and sex-matched control participants were recruited. Conventional echocardiography and 3-dimensional speckle-tracking echocardiography were performed, and global longitudinal strain, global circumferential strain, global area strain, and global radial strain values were measured. Significant differences in 2-dimensional LV functional patterns were found among the 3 groups (P = .031), and LV hypertrophy was the most prevalent in patients with diabetes and NAFL. The patients with diabetes only had significantly lower global longitudinal strain, global circumferential strain, and global radial strain than the controls (all P < .05). The patients with diabetes and NAFL had severely lower global longitudinal strain, global circumferential strain, global area strain, and global radial strain than the controls (all P < .001), and they also had severely lower global longitudinal strain, global area strain, and global radial strain than the patients with diabetes only (all P < 0.001). The hemoglobin A 1c level and NAFL were independently associated with strain values in all patients with diabetes. The strain values in multiple directions (≥2 of global longitudinal, global circumferential, global area, and global radial strain) decreased significantly in the patients with diabetes and moderate and severe NAFL compared to those with mild NAFL (all P < .05). Nonalcoholic fatty liver could aggravate LV hypertrophy and dysfunction in patients with type 2 diabetes. The combined application of conventional and 3-dimensional speckle-tracking echocardiography could detect these asymptomatic preclinical abnormalities. © 2018 by the American Institute of Ultrasound in Medicine.

  12. Different Type 1 Fimbrial Genes and Tropisms of Commensal and Potentially Pathogenic Actinomyces spp. with Different Salivary Acidic Proline-Rich Protein and Statherin Ligand Specificities

    PubMed Central

    Li, Tong; Khah, Massoud Kheir; Slavnic, Snjezana; Johansson, Ingegerd; Strömberg, Nicklas

    2001-01-01

    Actinomyces spp. exhibit type 1 fimbria-mediated adhesion to salivary acidic proline-rich proteins (PRPs) and statherin ligands. Actinomyces spp. with different animal and tissue origins belong to three major adhesion types as relates to ligand specificity and type 1 fimbria genes. (i) In preferential acidic-PRP binding, strains of Actinomyces naeslundii genospecies 1 and 2 from human and monkey mouths displayed at least three ligand specificities characterized by preferential acidic-PRP binding. Slot blot DNA hybridization showed seven highly conserved type 1 fimbria genes (orf1- to -6 and fimP) in genospecies 1 and 2 strains, except that orf5 and orf3 were divergent in genospecies 1. (ii) In preferential statherin binding, oral Actinomyces viscosus strains of rat and hamster origin (and strain 19246 from a human case of actinomycosis) bound statherin preferentially. DNA hybridization and characterization of the type 1 fimbria genes from strain 19246 revealed a homologous gene cluster of four open reading frames (orfA to -C and fimP). Bioinformatics suggested sortase (orfB, orf4, and part of orf5), prepilin peptidase (orfC and orf6), fimbria subunit (fimP), and usher- and autotransporter-like (orfA and orf1 to -3) functions. Those gene regions corresponding to orf3 and orf5 were divergent, those corresponding to orf2, orf1, and fimP were moderately conserved, and those corresponding to orf4 and orf6 were highly conserved. Restriction fragment length polymorphism analyses using a fimP probe separated human and monkey and rat and hamster strains into phylogenetically different groups. (iii) In statherin-specific binding, strains of A. naeslundii genospecies 1 from septic and other human infections displayed a low-avidity binding to statherin. Only the orf4 and orf6 gene regions were highly conserved. Finally, rat saliva devoid of statherin bound bacterial strains avidly irrespective of ligand specificity, and specific antisera detected either type 1, type 2, or both types of fimbria on the investigated Actinomyces strains. PMID:11705891

  13. Differential growth of Mycobacterium leprae strains (SNP genotypes) in armadillos.

    PubMed

    Sharma, Rahul; Singh, Pushpendra; Pena, Maria; Subramanian, Ramesh; Chouljenko, Vladmir; Kim, Joohyun; Kim, Nayong; Caskey, John; Baudena, Marie A; Adams, Linda B; Truman, Richard W

    2018-04-14

    Leprosy (Hansen's Disease) has occurred throughout human history, and persists today at a low prevalence in most populations. Caused by Mycobacterium leprae, the infection primarily involves the skin, mucosa and peripheral nerves. The susceptible host range for Mycobacterium leprae is quite narrow. Besides humans, nine banded armadillos (Dasypus novemcinctus) and red squirrels (Sciurus vulgaris) are the only other natural hosts for M. leprae, but only armadillos recapitulate the disease as seen in humans. Armadillos across the Southern United States harbor a single predominant genotypic strain (SNP Type-3I) of M. leprae, which is also implicated in the zoonotic transmission of leprosy. We investigated, whether the zoonotic strain (3I) has any notable growth advantages in armadillos over another genetically distant strain-type (SNP Type-4P) of M. leprae, and if M. leprae strains manifest any notably different pathology among armadillos. We co-infected armadillos (n = 6) with 2 × 10 9 highly viable M. leprae of both strains and assessed the relative growth and dissemination of each strain in the animals. We also analyzed 12 additional armadillos, 6 each individually infected with the same quantity of either strain. The infections were allowed to fulminate and the clinical manifestations of the disease were noted. Animals were humanely sacrificed at the terminal stage of infection and the number of bacilli per gram of liver, spleen and lymph node tissue were enumerated by Q-PCR assay. The growth of M. leprae strain 4P was significantly higher (P < 0.05) than 3I when each strain was propagated individually in armadillos. Significantly (P < 0.0001) higher growth of the 4P strain also was confirmed among animals co-infected with both 3I and 4P strain types using whole genome sequencing. Interestingly, the zoonotic strain does not exhibit any growth advantage in these non-human hosts, but the varied proliferation of the two M. leprae strains within armadillos suggest there are notable pathological variations between M. leprae strain-types. Copyright © 2018. Published by Elsevier B.V.

  14. Effect of Attachment Type on Denture Strain in Maxillary Implant Overdentures: Part 1. Overdenture with Palate.

    PubMed

    Takahashi, Toshihito; Gonda, Tomoya; Maeda, Yoshinobu

    This study examined the effects of attachments on strain in maxillary implant overdentures supported by two or four implants. A maxillary edentulous model with implants inserted into anterior, premolar, and molar areas was fabricated, and three types of unsplinted attachments-ball, locator, and magnet-were set on the implants distributed under various conditions. Maxillary experimental dentures were fabricated, and two strain gauges were attached at the anterior midline on the labial and palatal sides. A vertical occlusal load of 98 N was applied and shear strain of the dentures was measured. On both sides, magnet attachments resulted in the lowest shear strain, while ball attachments resulted in the highest shear strain under most conditions. However, differences in shear strain among the three attachment types were not significant when supported by four implants, especially molar implants. Shear strain of the maxillary implant overdenture was lowest when using magnet attachments. Magnet attachments mounted on four implants are recommended to prevent denture complications when using maxillary implant overdentures.

  15. Excretion of Wild-Type and Vaccine-Derived Poliovirus in the Feces of Poliovirus Receptor-Transgenic Mice

    PubMed Central

    Boot, Hein J.; Kasteel, Daniella T. J.; Buisman, Anne-Marie; Kimman, Tjeerd G.

    2003-01-01

    The emergence of circulating vaccine-derived poliovirus (cVDPV) strains in suboptimally vaccinated populations is a serious threat to the global poliovirus eradication. The genetic determinants for the transmissibility phenotype of polioviruses, and in particularly of cVDPV strains, are currently unknown. Here we describe the fecal excretion of wild-type poliovirus, oral polio vaccine, and cVDPV (Hispaniola) strains after intraperitoneal injection in poliovirus receptor-transgenic mice. Both the pattern and the level of fecal excretion of the cVDPV strains resemble those of wild-type poliovirus type 1. In contrast, very little poliovirus was present in the feces after oral polio vaccine administration. This mouse model will be helpful in elucidating the genetic determinants for the high fecal-oral transmission phenotype of cVDPV strains. PMID:12743311

  16. Simultaneous isolation of emm89-type Streptococcus pyogenes strains with a wild-type or mutated covS gene from a single streptococcal toxic shock syndrome patient.

    PubMed

    Masuno, Katsuaki; Okada, Ryo; Zhang, Yan; Isaka, Masanori; Tatsuno, Ichiro; Shibata, Shinichiro; Hasegawa, Tadao

    2014-04-01

    Streptococcal toxic shock syndrome (STSS) is a re-emerging infectious disease in many developed countries. Recent studies have suggested that mutations in CovRS, a two-component regulatory system in Streptococcus pyogenes, play important roles in the pathogenesis of STSS. However, in vivo evidence of the significance of CovRS in human infections has not been fully demonstrated. We investigated five S. pyogenes strains isolated simultaneously from the pharynx, sputum, knee joint, cerebrospinal fluid and blood of a single STSS patient. All were emm89-type strains, and multilocus sequence typing (MLST) analysis revealed that the strains of pharynx and blood were isogenic. The growth rates of the strains from pharynx and sputum were faster than those of the other strains. Protein profiles of the culture supernatants of strains from the pharynx and sputum were also different from those of the other strains. Sequence analyses revealed that strains from the knee joint, cerebrospinal fluid and blood contained a single nucleotide difference in the covS coding region, resulting in one amino acid change, compared with the other strains. Introduction of a plasmid containing the covS gene from the pharynx strain to the blood strain increased the production of SpeB protein. This suggests that the one amino acid alteration in CovS was relevant to pathogenesis. This report supports the idea that mutated CovS plays important roles in vivo in the dissemination of S. pyogenes from the upper respiratory tract of human to aseptic tissues such as blood and cerebrospinal fluid.

  17. Investigation of lactic acid bacterial strains for meat fermentation and the product's antioxidant and angiotensin-I-converting-enzyme inhibitory activities.

    PubMed

    Takeda, Shiro; Matsufuji, Hisashi; Nakade, Koji; Takenoyama, Shin-Ichi; Ahhmed, Abdulatef; Sakata, Ryoichi; Kawahara, Satoshi; Muguruma, Michio

    2017-03-01

    In the lactic acid bacteria (LAB) strains screened from our LAB collection, Lactobacillus (L.) sakei strain no. 23 and L. curvatus strain no. 28 degraded meat protein and tolerated salt and nitrite in vitro. Fermented sausages inoculated strains no. 23 and no. 28 showed not only favorable increases in viable LAB counts and reduced pH, but also the degradation of meat protein. The sausages fermented with these strains showed significantly higher antioxidant activity than those without LAB or fermented by each LAB type strain. Angiotensin-I-converting-enzyme (ACE) inhibitory activity was also significantly higher in the sausages fermented with strain no. 23 than in those fermented with the type strain. Higher ACE inhibitory activity was also observed in the sausages fermented with strain no. 28, but did not differ significantly from those with the type strain. An analysis of the proteolysis and degradation products formed by each LAB in sausages suggested that those bioactivities yielded fermentation products such as peptides. Therefore, LAB starters that can adequately ferment meat, such as strains no. 23 and no. 28, should contribute to the production of bioactive compounds in meat products. © 2016 Japanese Society of Animal Science.

  18. Mannose-specific interaction of Lactobacillus plantarum with porcine jejunal epithelium.

    PubMed

    Gross, Gabriele; van der Meulen, Jan; Snel, Johannes; van der Meer, Roelof; Kleerebezem, Michiel; Niewold, Theo A; Hulst, Marcel M; Smits, Mari A

    2008-11-01

    Host-microorganism interactions in the intestinal tract are complex, and little is known about specific nonpathogenic microbial factors triggering host responses in the gut. In this study, mannose-specific interactions of Lactobacillus plantarum 299v with jejunal epithelium were investigated using an in situ pig Small Intestinal Segment Perfusion model. The effects of L. plantarum 299v wild-type strain were compared with those of two corresponding mutant strains either lacking the gene encoding for the mannose-specific adhesin (msa) or sortase (srtA; responsible for anchoring of cell surface proteins like Msa to the cell wall). A slight enrichment of the wild-type strain associated with the intestinal surface could be observed after 8 h of perfusion when a mixture of wild-type and msa-mutant strain had been applied. In contrast to the mutant strains, the L. plantarum wild-type strain tended to induce a decrease in jejunal net fluid absorption compared with control conditions. Furthermore, after 8 h of perfusion expression of the host gene encoding pancreatitis-associated protein, a protein with proposed bactericidal properties, was found to be upregulated by the wild-type strain only. These observations suggest a role of Msa in the induction of host responses in the pig intestine.

  19. Description of Kribbella italica sp. nov., isolated from a Roman catacomb.

    PubMed

    Everest, Gareth J; Curtis, Sarah M; De Leo, Filomena; Urzì, Clara; Meyers, Paul R

    2015-02-01

    A novel actinobacterium, strain BC637(T), was isolated from a biodeteriogenic biofilm sample collected in 2009 in the Saint Callixstus Roman catacomb. The strain was found to belong to the genus Kribbella by analysis of the 16S rRNA gene. Phylogenetic analysis using the 16S rRNA gene and the gyrB, rpoB, relA, recA and atpD concatenated gene sequences showed that strain BC637(T) was most closely related to the type strains of Kribbella lupini and Kribbella endophytica. DNA-DNA hybridization experiments confirmed that strain BC637(T) is a genomic species that is distinct from its closest phylogenetic relatives, K. endophytica DSM 23718(T) (63 % DNA relatedness) and K. lupini LU14(T) (63 % DNA relatedness). Physiological comparisons showed that strain BC637(T) is phenotypically distinct from the type strains of K. endophytica and K. lupini. Thus, strain BC637(T) represents the type strain of a novel species, for which the name Kribella italica sp. nov. is proposed ( = DSM 28967(T) = NRRL B-59155(T)). © 2015 IUMS.

  20. Strain typing of acetic acid bacteria responsible for vinegar production by the submerged elaboration method.

    PubMed

    Fernández-Pérez, Rocío; Torres, Carmen; Sanz, Susana; Ruiz-Larrea, Fernanda

    2010-12-01

    Strain typing of 103 acetic acid bacteria isolates from vinegars elaborated by the submerged method from ciders, wines and spirit ethanol, was carried on in this study. Two different molecular methods were utilised: pulsed field gel electrophoresis (PFGE) of total DNA digests with a number of restriction enzymes, and enterobacterial repetitive intergenic consensus (ERIC) - PCR analysis. The comparative study of both methods showed that restriction fragment PFGE of SpeI digests of total DNA was a suitable method for strain typing and for determining which strains were present in vinegar fermentations. Results showed that strains of the species Gluconacetobacter europaeus were the most frequent leader strains of fermentations by the submerged method in the studied vinegars, and among them strain R1 was the predominant one. Results showed as well that mixed populations (at least two different strains) occurred in vinegars from cider and wine, whereas unique strains were found in spirit vinegars, which offered the most stressing conditions for bacterial growth. Copyright © 2010 Elsevier Ltd. All rights reserved.

  1. Phylogeny of 54 representative strains of species in the family Pasteurellaceae as determined by comparison of 16S rRNA sequences.

    PubMed Central

    Dewhirst, F E; Paster, B J; Olsen, I; Fraser, G J

    1992-01-01

    Virtually complete 16S rRNA sequences were determined for 54 representative strains of species in the family Pasteurellaceae. Of these strains, 15 were Pasteurella, 16 were Actinobacillus, and 23 were Haemophilus. A phylogenetic tree was constructed based on sequence similarity, using the Neighbor-Joining method. Fifty-three of the strains fell within four large clusters. The first cluster included the type strains of Haemophilus influenzae, H. aegyptius, H. aphrophilus, H. haemolyticus, H. paraphrophilus, H. segnis, and Actinobacillus actinomycetemcomitans. This cluster also contained A. actinomycetemcomitans FDC Y4, ATCC 29522, ATCC 29523, and ATCC 29524 and H. aphrophilus NCTC 7901. The second cluster included the type strains of A. seminis and Pasteurella aerogenes and H. somnus OVCG 43826. The third cluster was composed of the type strains of Pasteurella multocida, P. anatis, P. avium, P. canis, P. dagmatis, P. gallinarum, P. langaa, P. stomatis, P. volantium, H. haemoglobinophilus, H. parasuis, H. paracuniculus, H. paragallinarum, and A. capsulatus. This cluster also contained Pasteurella species A CCUG 18782, Pasteurella species B CCUG 19974, Haemophilus taxon C CAPM 5111, H. parasuis type 5 Nagasaki, P. volantium (H. parainfluenzae) NCTC 4101, and P. trehalosi NCTC 10624. The fourth cluster included the type strains of Actinobacillus lignieresii, A. equuli, A. pleuropneumoniae, A. suis, A. ureae, H. parahaemolyticus, H. parainfluenzae, H. paraphrohaemolyticus, H. ducreyi, and P. haemolytica. This cluster also contained Actinobacillus species strain CCUG 19799 (Bisgaard taxon 11), A. suis ATCC 15557, H. ducreyi ATCC 27722 and HD 35000, Haemophilus minor group strain 202, and H. parainfluenzae ATCC 29242. The type strain of P. pneumotropica branched alone to form a fifth group. The branching of the Pasteurellaceae family tree was quite complex. The four major clusters contained multiple subclusters. The clusters contained both rapidly and slowly evolving strains (indicated by differing numbers of base changes incorporated into the 16S rRNA sequence relative to outgroup organisms). While the results presented a clear picture of the phylogenetic relationships, the complexity of the branching will make division of the family into genera a difficult and somewhat subjective task. We do not suggest any taxonomic changes at this time. PMID:1548238

  2. A Video-Tracking Analysis-Based Behavioral Assay for Larvae of Anopheles pseudopunctipennis and Aedes aegypti (Diptera: Culicidae).

    PubMed

    Gonzalez, Paula V; Alvarez Costa, Agustín; Masuh, Héctor M

    2017-05-01

    Aedes aegypti (L.) is the primary vector of dengue, yellow fever, Zika, and chikungunya viruses, whereas Anopheles pseudopunctipennis (Theobald) is the principal vector for malaria in Latin America. The larval stage of these mosquitoes occurs in very different development habitats, and the study of their respective behaviors could give us valuable information to improve larval control. The aim of this study was to set up a bioassay to study basic larval behaviors using a video-tracking software. Larvae of An. pseudopunctipennis came from two localities in Salta Province, Argentina, while Ae. aegypti larvae were of the Rockefeller laboratory strain. Behaviors of individual fourth-instar larvae were documented in an experimental petri dish arena using EthoVision XT10.1 video-tracking software. The overall level of movement of larval An. pseudopunctipennis was lower than that for Ae. aegypti, and, while moving, larval An. pseudopunctipennis spent significantly more time swimming near the wall of the arena (thigmotaxis). This is the first study that analyzes the behavior of An. pseudopunctipennis larvae. The experimental system described here may be useful for future studies on the effect of physiological, toxicological, and chemosensory stimuli on larval behaviors. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. High sequence variations in the region containing genes encoding a cellular morphogenesis protein and the repressor of sexual development help to reveal origins of Aspergillus oryzae.

    PubMed

    Chang, Perng-Kuang; Scharfenstein, Leslie L; Solorzano, Cesar D; Abbas, Hamed K; Hua, Sui-Sheng T; Jones, Walker A; Zablotowicz, Robert M

    2015-05-04

    Aspergillus oryzae and Aspergillus flavus are closely related fungal species. The A. flavus morphotype that produces numerous small sclerotia (S strain) and aflatoxin has a unique 1.5 kb deletion in the norB-cypA region of the aflatoxin gene cluster (i.e. the S genotype). Phylogenetic studies have indicated that an isolate of the nonaflatoxigenic A. flavus with the S genotype is the ancestor of A. oryzae. Genome sequence comparison between A. flavus NRRL3357, which produces large sclerotia (L strain), and S-strain A. flavus 70S identified a region (samA-rosA) that was highly variable in the two morphotypes. A third type of samA-rosA region was found in A. oryzae RIB40. The three samA-rosA types were later revealed to be commonly present in A. flavus L-strain populations. Of the 182 L-strain A. flavus field isolates examined, 46%, 15% and 39% had the samA-rosA type of NRRL3357, 70S and RIB40, respectively. The three types also were found in 18 S-strain A. flavus isolates with different proportions. For A. oryzae, however, the majority (80%) of the 16 strains examined had the RIB40 type and none had the NRRL3357 type. The results suggested that A. oryzae strains in the current culture collections were mostly derived from the samA-rosA/RIB40 lineage of the nonaflatoxigenic A. flavus with the S genotype. Published by Elsevier B.V.

  4. Differentiation of Shewanella putrefaciens and Shewanella alga on the basis of whole-cell protein profiles, ribotyping, phenotypic characterization, and 16S rRNA gene sequence analysis.

    PubMed Central

    Vogel, B F; Jørgensen, K; Christensen, H; Olsen, J E; Gram, L

    1997-01-01

    Seventy-six presumed Shewanella putrefaciens isolates from fish, oil drillings, and clinical specimens, the type strain of Shewanella putrefaciens (ATCC 8071), the type strain of Shewanella alga (IAM 14159), and the type strain of Shewanella hanedai (ATCC 33224) were compared by several typing methods. Numerical analysis of sodium dodecyl sulfate-polyacrylamide gel electrophoresis of whole-cell protein and ribotyping patterns showed that the strains were separated into two distinct clusters with 56% +/- 10% and 40% +/- 14% similarity for whole-cell protein profiling and ribotyping, respectively. One cluster consisted of 26 isolates with 52 to 55 mol% G + C and included 15 human isolates, mostly clinical specimens, 8 isolates from marine waters, and the type strain of S. alga. This homogeneous cluster of mesophilic, halotolerant strains was by all analyses identical to the recently defined species S. alga (U. Simidu et al., Int. J. Syst. Bacteriol, 40:331-336, 1990). Fifty-two typically psychrotolerant strains formed the other, more heterogeneous major cluster, with 43 to 47 mol% G + C. The type strain of S. putrefaciens was included in this group. The two groups were confirmed by 16S rRNA gene sequence analysis. It is concluded that the isolates must be considered two different species, S. alga and S. putrefaciens, and that most mesophilic isolates formerly identified as S. putrefaciens belong to S. alga. The ecological role and potential pathogenicity of S. alga can be evaluated only if the organism is correctly identified. PMID:9172338

  5. Genotyping of Indian antigenic, vaccine, and field Brucella spp. using multilocus sequence typing.

    PubMed

    Shome, Rajeswari; Krithiga, Natesan; Shankaranarayana, Padmashree B; Jegadesan, Sankarasubramanian; Udayakumar S, Vishnu; Shome, Bibek Ranjan; Saikia, Girin Kumar; Sharma, Narendra Kumar; Chauhan, Harshad; Chandel, Bharat Singh; Jeyaprakash, Rajendhran; Rahman, Habibur

    2016-03-31

    Brucellosis is one of the most important zoonotic diseases that affects multiple livestock species and causes great economic losses. The highly conserved genomes of Brucella, with > 90% homology among species, makes it important to study the genetic diversity circulating in the country. A total of 26 Brucella spp. (4 reference strains and 22 field isolates) and 1 B. melitensis draft genome sequence from India (B. melitensis Bm IND1) were included for sequence typing. The field isolates were identified by biochemical tests and confirmed by both conventional and quantitative polymerase chain reaction (qPCR) targeting bcsp 31Brucella genus-specific marker. Brucella speciation and biotyping was done by Bruce ladder, probe qPCR, and AMOS PCRs, respectively, and genotyping was done by multilocus sequence typing (MLST). The MLST typing of 27 Brucella spp. revealed five distinct sequence types (STs); the B. abortus S99 reference strain and 21 B. abortus field isolates belonged to ST1. On the other hand, the vaccine strain B. abortus S19 was genotyped as ST5. Similarly, B. melitensis 16M reference strain and one B. melitensis field isolate were grouped into ST7. Another B. melitensis field isolate belonged to ST8 (draft genome sequence from India), and only B. suis 1330 reference strain was found to be ST14. The sequences revealed genetic similarity of the Indian strains to the global reference and field strains. The study highlights the usefulness of MLST for typing of field isolates and validation of reference strains used for diagnosis and vaccination against brucellosis.

  6. Aliisedimentitalea scapharcae gen. nov., sp. nov., isolated from ark shell Scapharca broughtonii.

    PubMed

    Kim, Young-Ok; Park, Sooyeon; Nam, Bo-Hye; Kim, Dong-Gyun; Won, Sung-Min; Park, Ji-Min; Yoon, Jung-Hoon

    2015-08-01

    A Gram-negative, aerobic, non-spore-forming, motile and ovoid or rod-shaped bacterial strain, designated MA2-16(T), was isolated from ark shell (Scapharca broughtonii) collected from the South Sea, South Korea. Strain MA2-16(T) was found to grow optimally at 30°C, at pH 7.0-8.0 and in the presence of 2.0% (w/v) NaCl. Neighbour-joining, maximum-likelihood and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences revealed that strain MA2-16(T) clustered with the type strain of Sedimentitalea nanhaiensis. The novel strain exhibited a 16S rRNA gene sequence similarity value of 97.1% to the type strain of S. nanhaiensis. In the neighbour-joining phylogenetic tree based on gyrB sequences, strain MA2-16(T) formed an evolutionary lineage independent of those of other taxa. Strain MA2-16(T) contained Q-10 as the predominant ubiquinone and C18:1 ω7c and 11-methyl C18:1 ω7c as the major fatty acids. The major polar lipids of strain MA2-16(T) were phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, an unidentified aminolipid and an unidentified lipid. The DNA G+C content of strain MA2-16(T) was 57.7 mol% and its DNA-DNA relatedness values with the type strains of S. nanhaiensis and some phylogenetically related species of the genera Leisingera and Phaeobacter were 13-24%. On the basis of the data presented, strain MA2-16(T) is considered to represent a novel genus and novel species within the family Rhodobacteraceae, for which the name Aliisedimentitalea scapharcae gen. nov., sp. nov. is proposed. The type strain is MA2-16(T) (=KCTC 42119(T) =CECT 8598(T)).

  7. Differential expression of type X collagen in a mechanically active 3-D chondrocyte culture system: a quantitative study

    PubMed Central

    Yang, Xu; Vezeridis, Peter S; Nicholas, Brian; Crisco, Joseph J; Moore, Douglas C; Chen, Qian

    2006-01-01

    Objective Mechanical loading of cartilage influences chondrocyte metabolism and gene expression. The gene encoding type X collagen is expressed specifically by hypertrophic chondrocytes and up regulated during osteoarthritis. In this study we tested the hypothesis that the mechanical microenvironment resulting from higher levels of local strain in a three dimensional cell culture construct would lead to an increase in the expression of type X collagen mRNA by chondrocytes in those areas. Methods Hypertrophic chondrocytes were isolated from embryonic chick sterna and seeded onto rectangular Gelfoam sponges. Seeded sponges were subjected to various levels of cyclic uniaxial tensile strains at 1 Hz with the computer-controlled Bio-Stretch system. Strain distribution across the sponge was quantified by digital image analysis. After mechanical loading, sponges were cut and the end and center regions were separated according to construct strain distribution. Total RNA was extracted from the cells harvested from these regions, and real-time quantitative RT-PCR was performed to quantify mRNA levels for type X collagen and a housing-keeping gene 18S RNA. Results Chondrocytes distributed in high (9%) local strain areas produced more than two times type X collagen mRNA compared to the those under no load conditions, while chondrocytes located in low (2.5%) local strain areas had no appreciable difference in type X collagen mRNA production in comparison to non-loaded samples. Increasing local strains above 2.5%, either in the center or end regions of the sponge, resulted in increased expression of Col X mRNA by chondrocytes in that region. Conclusion These findings suggest that the threshold of chondrocyte sensitivity to inducing type X collagen mRNA production is more than 2.5% local strain, and that increased local strains above the threshold results in an increase of Col X mRNA expression. Such quantitative analysis has important implications for our understanding of mechanosensitivity of cartilage and mechanical regulation of chondrocyte gene expression. PMID:17150098

  8. Fear, Rationality and Opportunity: Reasons and Motives for Not Trying Ecstasy

    ERIC Educational Resources Information Center

    Vervaeke, Hylke Karen Eva; Benschop, Annemieke; Korf, Dirk Jan

    2008-01-01

    Aim: To gain more insight into the reasons and motives why people do not start taking ecstasy. Method: As part of the NeXT Study, we prospectively monitored 188 subjects who were ecstasy-naive at baseline but seemed likely to take ecstasy (MDMA) of their own accord during the course of the study. After an 11- to 26-month follow-up period, 160…

  9. Existence and uniqueness of solutions to a class of nonlinear-operator-differential equations arising in automated spaceship navigation

    NASA Technical Reports Server (NTRS)

    Bogdan, V. M.

    1981-01-01

    A proof is given of the existence and uniqueness of the solution to the automatic control problem with a nonlinear state equation of the form y' = f(t,y,u) and nonlinear operator controls u = U(y) acting onto the state function y which satisfies the initial condition y(t) = x(t) for t or = 0.

  10. Stellar Inertial Navigation Workstation

    NASA Technical Reports Server (NTRS)

    Johnson, W.; Johnson, B.; Swaminathan, N.

    1989-01-01

    Software and hardware assembled to support specific engineering activities. Stellar Inertial Navigation Workstation (SINW) is integrated computer workstation providing systems and engineering support functions for Space Shuttle guidance and navigation-system logistics, repair, and procurement activities. Consists of personal-computer hardware, packaged software, and custom software integrated together into user-friendly, menu-driven system. Designed to operate on IBM PC XT. Applied in business and industry to develop similar workstations.

  11. U.S. EPA, Pesticide Product Label, PYRE-MIST 3610, 05/21/1982

    EPA Pesticide Factsheets

    2011-04-14

    ... "fO~ 1'lf Cf.t C.I'; tt d~l;f.td .rth !,t,"fd "t~~t!tS _"",tI tr.td f~· ~ J ... _ .... CII.1$ ~.1'f Gf ff'flO'.t fl~R4 food ~f14 bxlr..aa..;;,& s.,;rt,f:{H C::.r !xt:I .rlJ stl"t lift .11111 ...

  12. Adaptive Filtering in the Wavelet Transform Domain via Genetic Algorithms

    DTIC Science & Technology

    2004-08-06

    wavelet transforms. Whereas the term “evolved” pertains only to the altered wavelet coefficients used during the inverse transform process. 2...words, the inverse transform produces the original signal x(t) from the wavelet and scaling coefficients. )()( ,, tdtx nk n nk k ψ...reconstruct the original signal as accurately as possible. The inverse transform reconstructs an approximation of the original signal (Burrus

  13. Proceedings of Colloquium on Stable Solutions of Some Ill-Posed Problems, October 9, 1979.

    DTIC Science & Technology

    1980-06-30

    4. In (24] iterative process (9) was applied for calculation of the magnetization of thin magnetic films . This problem is of interest for computer...equation fl I (x-t) -f(t) = g(x), x > 1. (i) Its multidimensional analogue fmX-tK-if(t)dt = g(x), xEA, AnD (2) can be intepreted as the problem of

  14. Analysis of Ejection Seat Stability Using Easy Program. Volume I.

    DTIC Science & Technology

    1980-09-01

    BODY AXiS FURCE COMPONENT. L ACTING ON THE AiRPLANc FROM THE CATAPULT (Ld) C ILA1(3) - PORT ONE X,Y,L AIRPLANE BODY AXIS TORQUE COMPONENTS C ACrINu...THE AIRPLANE (FT) C EAPI3) - EARTH TO AIRPLANc . EULER ANGLES (DEG) C SKPt3) - XtYZ EARTh POSITIGN VECTOR OF THE SEAT REFERENCE L POINT (FT) f- LST(3

  15. Finding Rational Parametric Curves of Relative Degree One or Two

    ERIC Educational Resources Information Center

    Boyles, Dave

    2010-01-01

    A plane algebraic curve, the complete set of solutions to a polynomial equation: f(x, y) = 0, can in many cases be drawn using parametric equations: x = x(t), y = y(t). Using algebra, attempting to parametrize by means of rational functions of t, one discovers quickly that it is not the degree of f but the "relative degree," that describes how…

  16. Differential growth of U and M type infectious haematopoietic necrosis virus in a rainbow trout–derived cell line, RTG-2

    USGS Publications Warehouse

    Kurath, Gael; Purcell, Maureen K.; Wargo, Andrew; Park, Jeong Woo; Moon, Chang Hoon

    2010-01-01

    Infectious haematopoietic necrosis virus (IHNV) is one of the most important viral pathogens of salmonids. In rainbow trout, IHNV isolates in the M genogroup are highly pathogenic, while U genogroup isolates are significantly less pathogenic. We show here that, at a multiplicity of infection (MOI) of 1, a representative U type strain yielded 42-fold less infectious virus than an M type strain in the rainbow trout–derived RTG-2 cell line at 24 h post-infection (p.i.). However, at an MOI of 10, there was only fivefold difference in the yield of infectious virus between the U and M strains. Quantification of extracellular viral genomic RNA suggested that the number of virus particles released from cells infected with the U strain at a MOI of 1 was 47-fold lower than from M-infected cells, but U and M virions were equally infectious by particle to infectivity ratios. At an MOI of 1, U strain intracellular viral genome accumulation and transcription were 37- and 12-fold lower, respectively, than those of the M strain at 24 h p.i. Viral nucleocapsid (N) protein accumulation in U strain infections was fivefold lower than in M strain infections. These results suggest that the block in U type strain growth in RTG-2 cells was because of the effects of reduced genome replication and transcription. The reduced growth of the U strain does not seem to be caused by defective genes, because the U and M strains grew equally well in the permissive epithelioma papulosum cyprini cell line at an MOI of 1. This suggests that host-specific factors in RTG-2 cells control the growth of the IHNV U and M strains differently, leading to growth restriction of the U type virus during the RNA synthesis step.

  17. Application of the fractional Levy motion to precipitation data

    NASA Astrophysics Data System (ADS)

    Kuzuha, Y.; Tachinami, S.; Gomi, C.

    2012-12-01

    We applied the fractional Lévy motion model to precipitation data, referring to Lavallée (2004) and Lavallée (2008). The data we used were from the Global Preciptiation Climatology Centre (GPCC) monthly precipitation dataset. These data consist of 360 (longitude) × 180 (latitude) × 1336 (monthly, 1901-2012). First, we constructed four datasets: time series of average monthly precipitation of the top (maximum) 1000 precipitation observation stations, top 10, top 100, and top 500. Next, according to Lavallée (2004) and Lavallée (2008), using Fourier transformation, convolution (filtering) and inverse Fourier transformation, we obtained random variables Xt (Lavallée, 2004) from Yt (precipitation). We transformed from Yt to Xt. Finally, we fitted the Lévy law to Xt. As a preliminary result, we present examples of the values of the Lévy law parameters: alpha, beta, gamma, and delta for the "top 100" dataset. Parameters obtained were (1.17, 0.0, 257.6, 0.28; maximum likelihood), (1.10, 0.0, 250.0, -0.99; quantile algorithm), and (1.20, 0.0, 265.1, 0.57; empirical characteristic function algorithm). We used J. P. Nolan's algorithm. The values are quite sensitive to the algorithm that is used. At the Fall meeting, we will present considerations and results obtained using precipitation data other than those of the GPCC. J. P. Nolan, http://academic2.american.edu/~jpnolan/stable/stable.html Lavallée (2004), Stochastic modeling of climatic variability in dendrochronology, GRL, 31, L15202. Lavallée (2008), On the random nature of earthquake sources and ground motions; a unified theory, Advances in Geophysics, 50, chapter 16. Acknowledgement: We thank Dr. D. Lavallee for his comments and suggestions.; An example of results which we obtained. On a log-log plot, PDF of the Lévy law (red line) is more appropriate than the Gaussian law (blue line) in terms of heavy tail or extreme values. This is consistent with Lavallée (2004) and Lavallée (2008) who used slip distribution and climate (dendrochronology) data.

  18. Application of Deep Learning Architectures for Accurate and Rapid Detection of Internal Mechanical Damage of Blueberry Using Hyperspectral Transmittance Data.

    PubMed

    Wang, Zhaodi; Hu, Menghan; Zhai, Guangtao

    2018-04-07

    Deep learning has become a widely used powerful tool in many research fields, although not much so yet in agriculture technologies. In this work, two deep convolutional neural networks (CNN), viz. Residual Network (ResNet) and its improved version named ResNeXt, are used to detect internal mechanical damage of blueberries using hyperspectral transmittance data. The original structure and size of hypercubes are adapted for the deep CNN training. To ensure that the models are applicable to hypercube, we adjust the number of filters in the convolutional layers. Moreover, a total of 5 traditional machine learning algorithms, viz. Sequential Minimal Optimization (SMO), Linear Regression (LR), Random Forest (RF), Bagging and Multilayer Perceptron (MLP), are performed as the comparison experiments. In terms of model assessment, k-fold cross validation is used to indicate that the model performance does not vary with the different combination of dataset. In real-world application, selling damaged berries will lead to greater interest loss than discarding the sound ones. Thus, precision, recall, and F1-score are also used as the evaluation indicators alongside accuracy to quantify the false positive rate. The first three indicators are seldom used by investigators in the agricultural engineering domain. Furthermore, ROC curves and Precision-Recall curves are plotted to visualize the performance of classifiers. The fine-tuned ResNet/ResNeXt achieve average accuracy and F1-score of 0.8844/0.8784 and 0.8952/0.8905, respectively. Classifiers SMO/ LR/RF/Bagging/MLP obtain average accuracy and F1-score of 0.8082/0.7606/0.7314/0.7113/0.7827 and 0.8268/0.7796/0.7529/0.7339/0.7971, respectively. Two deep learning models achieve better classification performance than the traditional machine learning methods. Classification for each testing sample only takes 5.2 ms and 6.5 ms respectively for ResNet and ResNeXt, indicating that the deep learning framework has great potential for online fruit sorting. The results of this study demonstrate the potential of deep CNN application on analyzing the internal mechanical damage of fruit.

  19. Application of Deep Learning Architectures for Accurate and Rapid Detection of Internal Mechanical Damage of Blueberry Using Hyperspectral Transmittance Data

    PubMed Central

    Hu, Menghan; Zhai, Guangtao

    2018-01-01

    Deep learning has become a widely used powerful tool in many research fields, although not much so yet in agriculture technologies. In this work, two deep convolutional neural networks (CNN), viz. Residual Network (ResNet) and its improved version named ResNeXt, are used to detect internal mechanical damage of blueberries using hyperspectral transmittance data. The original structure and size of hypercubes are adapted for the deep CNN training. To ensure that the models are applicable to hypercube, we adjust the number of filters in the convolutional layers. Moreover, a total of 5 traditional machine learning algorithms, viz. Sequential Minimal Optimization (SMO), Linear Regression (LR), Random Forest (RF), Bagging and Multilayer Perceptron (MLP), are performed as the comparison experiments. In terms of model assessment, k-fold cross validation is used to indicate that the model performance does not vary with the different combination of dataset. In real-world application, selling damaged berries will lead to greater interest loss than discarding the sound ones. Thus, precision, recall, and F1-score are also used as the evaluation indicators alongside accuracy to quantify the false positive rate. The first three indicators are seldom used by investigators in the agricultural engineering domain. Furthermore, ROC curves and Precision-Recall curves are plotted to visualize the performance of classifiers. The fine-tuned ResNet/ResNeXt achieve average accuracy and F1-score of 0.8844/0.8784 and 0.8952/0.8905, respectively. Classifiers SMO/ LR/RF/Bagging/MLP obtain average accuracy and F1-score of 0.8082/0.7606/0.7314/0.7113/0.7827 and 0.8268/0.7796/0.7529/0.7339/0.7971, respectively. Two deep learning models achieve better classification performance than the traditional machine learning methods. Classification for each testing sample only takes 5.2 ms and 6.5 ms respectively for ResNet and ResNeXt, indicating that the deep learning framework has great potential for online fruit sorting. The results of this study demonstrate the potential of deep CNN application on analyzing the internal mechanical damage of fruit. PMID:29642454

  20. Bacterial colonization of the implant-abutment interface of conical connection with an internal octagon: an in vitro study using real-time PCR.

    PubMed

    Baj, A; Beltramini, G A; Bolzoni, A; Cura, F; Palmieri, A; Scarano, A; Ottria, L; Giannì, A B

    2017-01-01

    Bacterial leakage at the implant-abutment connection of a two-piece implant system is considered the main cause of peri-implantitis. Prevention of bacterial leakage at the implant-abutment connection is mandatory for reducing inflammation process around implant neck and achieving bone stability. Micro-cavities at implant-abutment connection level can favour bacterial leakage, even in modern two-piece implant systems. The conical connection with an internal octagon (CCIO) is considered to be more stable mechanically and allows a more tight link between implant and abutment. As P. gingivalis and T. forsythia penetration might have clinical relevance, it was the purpose of this investigation to evaluate molecular leakage of these two bacteria in a new two-implant system with an internal conical implant-abutment connection with internal octagon (Shiner XT, FMD Falappa Medical Devices S.p.A. Rome, Italy). To verify the ability of the implant in protecting the internal space from the external environment, the passage of genetically modified Escherichia c oli across implant-abutment interface was evaluated. Four Shiner XT implants (FMD, Falappa Medical Devices®, Rome, Italy) were immerged in a bacterial culture for 24 h and bacteria amount was measured inside implant-abutment interface with Real-time PCR. Bacteria were detected inside all studied implants, with a median percentage of 6% for P. gingivalis and 5% for T. forsythia. Other comparable studies about the tightness of the tested implant system reported similar results. The gap size at the implant-abutment connection of CCIOs was measured by other authors discovering a gap size of 1–2μm of the AstraTech system and of 4μm for the Ankylos system. Bacterial leakage along implant-abutment connection of cylindrical and tapered implants, Shiner XT, (FMD Falappa Medical Devices S.p.A. Rome, Italy) showed better results compared to other implants. Additional studies are needed to explore the relationship in terms of microbiota of the CCIO. In addition, the dynamics of internal colonization needs to be thoroughly documented in longitudinal in vivo studies.

  1. Phylogenetic analysis of Mycobacterium massiliense strains having recombinant rpoB gene laterally transferred from Mycobacterium abscessus.

    PubMed

    Kim, Byoung-Jun; Kim, Ga-Na; Kim, Bo-Ram; Shim, Tae-Sun; Kook, Yoon-Hoh; Kim, Bum-Joon

    2017-01-01

    Recent multi locus sequence typing (MLST) and genome based studies indicate that lateral gene transfer (LGT) events in the rpoB gene are prevalent between Mycobacterium abscessus complex strains. To check the prevalence of the M. massiliense strains subject to rpoB LGT (Rec-mas), we applied rpoB typing (711 bp) to 106 Korean strains of M. massiliense infection that had already been identified by hsp65 sequence analysis (603 bp). The analysis indicated 6 smooth strains in M. massiliense Type I (10.0%, 6/60) genotypes but no strains in M. massiliense Type II genotypes (0%, 0/46), showing a discrepancy between the 2 typing methods. Further MLST analysis based on the partial sequencing of seven housekeeping genes, argH, cya, glpK, gnd, murC, pta and purH, as well as erm(41) PCR proved that these 6 Rec-mas strains consisted of two distinct genotypes belonging to M. massiliense and not M. abscessus. The complete rpoB sequencing analysis showed that these 6 Rec-mas strains have an identical hybrid rpoB gene, of which a 478 bp partial rpoB fragment may be laterally transferred from M. abscessus. Notably, five of the 6 Rec-mas strains showed complete identical sequences in a total of nine genes, including the seven MLST genes, hsp65, and rpoB, suggesting their clonal propagation in South Korea. In conclusion, we identified 6 M. massiliense smooth strains of 2 phylogenetically distinct genotypes with a specific hybrid rpoB gene laterally transferred from M. abscessus from Korean patients. Their clinical relevance and bacteriological traits remain to be elucidated.

  2. Phylogenetic analysis of Mycobacterium massiliense strains having recombinant rpoB gene laterally transferred from Mycobacterium abscessus

    PubMed Central

    Kim, Byoung-Jun; Kim, Ga-Na; Kim, Bo-Ram; Shim, Tae-Sun; Kook, Yoon-Hoh

    2017-01-01

    Recent multi locus sequence typing (MLST) and genome based studies indicate that lateral gene transfer (LGT) events in the rpoB gene are prevalent between Mycobacterium abscessus complex strains. To check the prevalence of the M. massiliense strains subject to rpoB LGT (Rec-mas), we applied rpoB typing (711 bp) to 106 Korean strains of M. massiliense infection that had already been identified by hsp65 sequence analysis (603 bp). The analysis indicated 6 smooth strains in M. massiliense Type I (10.0%, 6/60) genotypes but no strains in M. massiliense Type II genotypes (0%, 0/46), showing a discrepancy between the 2 typing methods. Further MLST analysis based on the partial sequencing of seven housekeeping genes, argH, cya, glpK, gnd, murC, pta and purH, as well as erm(41) PCR proved that these 6 Rec-mas strains consisted of two distinct genotypes belonging to M. massiliense and not M. abscessus. The complete rpoB sequencing analysis showed that these 6 Rec-mas strains have an identical hybrid rpoB gene, of which a 478 bp partial rpoB fragment may be laterally transferred from M. abscessus. Notably, five of the 6 Rec-mas strains showed complete identical sequences in a total of nine genes, including the seven MLST genes, hsp65, and rpoB, suggesting their clonal propagation in South Korea. In conclusion, we identified 6 M. massiliense smooth strains of 2 phylogenetically distinct genotypes with a specific hybrid rpoB gene laterally transferred from M. abscessus from Korean patients. Their clinical relevance and bacteriological traits remain to be elucidated. PMID:28604829

  3. The change of macrolide resistance rates in group A Streptococcus isolates from children between 2002 and 2013 in Asahikawa city.

    PubMed

    Sakata, Hiroshi

    2015-05-01

    This study targeted patients in the Department of Pediatrics, Asahikawa Kosei Hospital, between January 2002 and December 2013. In patients suspected of having hemolytic streptococcal infection, Group A Streptococcus (GAS) strains isolated from a throat swab were examined for antimicrobial susceptibility testing. The MICs were measured by the broth microdilution method. The annual number of GAS strains examined for antimicrobial susceptibility testing ranged from 28 to 65 strains, for a total of 574 strains. Some of the isolates obtained from 2006 to 2009 and from 2011 to 2013 were analyzed to determine their emm types. An erythromycin (EM) resistant strain was not detected until 2004, but one EM-resistant strain appeared in 2005. Subsequently, EM-resistant strains rapidly increased, and 48 of 65 strains (73.8%) examined in 2009 were resistant. In 2010, the number of EM-resistant strains decreased to 12 of 36 strains (33.3%). However, it gradually increased afterwards, and 37 of 60 strains (61.7%) were resistant in 2013. Out of 574 strains examined, 184 exhibited EM-resistance, and the overall resistance rate was 31.9%. Partitioning the 124 strains examined between 2006 and 2008 according to emm types, only emm28 strains, which exhibited a high resistance rate, and emm12 strains demonstrated resistance. For the 142 strains examined between 2011 and 2013, the resistance rate of emm28 strains was similarly high; the resistance of emm12 strains significantly increased, and emm1 strains exhibited a high resistance rate. The number of emm types associated with the resistant strains increased. Copyright © 2015 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  4. Relationship between axenic growth of Dictyostelium discoideum strains and their track morphology on substrates coated with gold particles

    PubMed Central

    1983-01-01

    Amoebae of Dictyostelium discoideum produce tracks with two distinct morphologies on gold-coated coverslips. The wild-type strain and other strains that feed only by phagocytosis produced indistinct, fuzzy tracks, whereas mutants capable of axenic growth produced clear, sharp tracks. The sharp track morphology was found to be a recessive phenotype that segregates with axenicity and probably requires a previously unidentified axenic mutation. Axenic and nonaxenic strains also differed in their ability to pinocytose. When the two types of cells were shifted from bacterial growth plates to nutrient media, within 24 h the axenic strain established a rapid rate of pinocytosis, approximately 100-fold higher than the low rate detectable for the nonaxenic strain. However, track formation did not appear to be directly related to endocytosis. Electron microscopic examination of cells during track formation showed that both axenic and nonaxenic strains accumulated gold particles on their surfaces, but neither strain internalized the gold to any significant degree. Observation of living cells revealed that axenic strains collected all particles that they contacted, whereas wild-type strains left many particles undisturbed. The size of the gold particle clusters discarded by the cells also contributed to track morphology. PMID:6619183

  5. The use of (GTG)5 oligonucleotide as an RAPD primer to type Campylobacter concisus.

    PubMed

    Matsheka, M I; Lastovica, A J; Zappe, H; Elisha, B G

    2006-06-01

    DNA fingerprinting using (GTG)(5) oligonucleotide as a primer in a random amplified polymorphic DNA (RAPD) assay was assessed by typing isolates of Campylobacter concisus strains, collected over a period of 8 years. RAPD analysis using the (GTG)(5) oligonucleotide as a primer was used to type 100 isolates of C. concisus comprising mostly isolates from children with diarrhoea. Using this method, 86% of the isolates were found to be genotypically diverse. Of these heterogeneous isolates, 25 of the strains were also shown to be genetically distinct in a previous study using pulsed field gel electrophoresis. The remaining isolates (14) could be classified into five profile groups based on the DNA fingerprinting patterns. The assay successfully identified epidemiologically linked strains from the unrelated genetically diverse pool of strains. Laboratory RADP typing using the (GTG)(5) primer proved to be useful in distinguishing related strains of C. concisus from a large pool of unrelated strains of this organism. RAPD typing using (GTG)(5) is a simple method that could be used to investigate the epidemiology of C. concisus. The results suggest that homologous lineages of C. concisus may exist within an otherwise heterogeneous species complex. However, these data need to be confirmed using a more robust typing method.

  6. The proportion of non-aflatoxigenic strains of the Aspergillus flavus/oryzae complex from meju by analyses of the aflatoxin biosynthetic genes.

    PubMed

    Hong, Seung-Beom; Lee, Mina; Kim, Dae-Ho; Chung, Soo-Hyun; Shin, Hyeon-Dong; Samson, Robert A

    2013-12-01

    Strains of the Aspergillus flavus/oryzae complex are frequently isolated from meju, a fermented soybean product, that is used as the starting material for ganjang (soy sauce) and doenjang (soybean paste) production. In this study, we examined the aflatoxin producing capacity of A. flavus/oryzae strains isolated from meju. 192 strains of A. flavus/oryzae were isolated from more than 100 meju samples collected from diverse regions of Korea from 2008 to 2011, and the norB-cypA, omtA, and aflR genes in the aflatoxin biosynthesis gene cluster were analyzed. We found that 178 strains (92.7%) belonged to non-aflatoxigenic group (Type I of norB-cypA, IB-L-B-, IC-AO, or IA-L-B- of omtA, and AO type of aflR), and 14 strains (7.3%) belonged to aflatoxin-producible group (Type II of norB-cypA, IC-L-B+/B- or IC-L-B+ of omtA, and AF type of aflR). Only 7 strains (3.6%) in the aflatoxin-producible group produced aflatoxins on Czapek yeast-extract medium. The aflatoxin-producing capability of A. flavus/oryzae strains from other sources in Korea were also investigated, and 92.9% (52/56) strains from air, 93.9% (31/33) strains from rice straw, 91.7% (11/12) strains from soybean, 81.3% (13/16) strains from corn, 82% (41/50) strains from peanut, and 73.2% (41/56) strains from arable soil were included in the non-aflatoxigenic group. The proportion of non-aflatoxigenicity of meju strains was similar to that of strains from soybean, air and rice straw, all of which have an effect on the fermentation of meju. The data suggest that meju does not have a preference for non-aflatoxigenic or aflatoxin-producible strains of A. flavus/oryzae from the environment of meju. The non-aflatoxigenic meju strains are proposed to be named A. oryzae, while the meju strains that can produce aflatoxins should be referred to A. flavus in this study.

  7. Description of Lutimonas halocynthiae sp. nov., isolated from a golden sea squirt (Halocynthia aurantium), reclassification of Aestuariicola saemankumensis as Lutimonas saemankumensis comb. nov. and emended description of the genus Lutimonas.

    PubMed

    Kim, Young-Ok; Park, Sooyeon; Nam, Bo-Hye; Jung, Yong-Taek; Kim, Dong-Gyun; Bae, Kyung Sook; Yoon, Jung-Hoon

    2014-06-01

    A Gram-stain-negative, non-motile, coccoid, ovoid or rod-shaped bacterial strain, designated RSS3-C1(T), was isolated from a golden sea squirt (Halocynthia aurantium) collected from the East Sea, South Korea. Strain RSS3-C1(T) was found to grow optimally at 20-25 °C, at pH 7.0-8.0 and in the presence of 2.0% (w/v) NaCl. Phylogenetic trees based on 16S rRNA gene sequences revealed that strain RSS3-C1(T) clustered with the type strains of Lutimonas vermicola and Aestuariicola saemankumensis. Strain RSS3-C1(T) exhibited 98.8% 16S rRNA gene sequence similarity to each type strain. Strain RSS3-C1(T) contained MK-6 as the predominant menaquinone and iso-C(15 : 0), iso-C(17 : 0) 3-OH and anteiso-C(15 : 0) as the major fatty acids. The major polar lipids of strain RSS3-C1(T) were phosphatidylethanolamine and two unidentified lipids. The DNA G+C content of strain RSS3-C1(T) was 39.2 mol%, and DNA-DNA relatedness to the type strains of and was 21±5.3 and 26±7.5 %, respectively. The differential phenotypic properties, together with its phylogenetic and genetic distinctiveness, revealed that strain RSS3-C1(T) is separated from and . On the basis of the data presented, strain RSS3-C1(T) is considered to represent a novel species of the genus Lutimonas, for which the name Lutimonas halocynthiae sp. nov. is proposed. The type strain is RSS3-C1(T) ( = KCTC 32537(T) = CECT 8444(T)). In this study, it is also proposed that Aestuariicola saemankumensis should be reclassified as a member of the genus Lutimonas, as Lutimonas saemankumensis comb. nov. (type strain SMK-142(T) = KCTC 22171(T) = CCUG 55329(T)), and the description of the genus Lutimonas is emended. © 2014 IUMS.

  8. Evaluation of antimicrobial susceptibilities and virulence factors of Staphylococcus aureus strains isolated from community-acquired and health-care associated pediatric infections.

    PubMed

    Karbuz, Adem; Karahan, Zeynep Ceren; Aldemir-Kocabaş, Bilge; Tekeli, Alper; Özdemir, Halil; Güriz, Haluk; Gökdemir, Refik; İnce, Erdal; Çiftçi, Ergin

    2017-01-01

    Karbuz A, Karahan ZC, Aldemir-Kocabaş B, Tekeli A, Özdemir H, Güriz H, Gökdemir R, İnce E, Çiftçi E. Evaluation of antimicrobial susceptibilities and virulence factors of Staphylococcus aureus strains isolated from community-acquired and health-care associated pediatric infections. Turk J Pediatr 2017; 59: 395-403. The aim of this study was to investigate the enterotoxins and Panton-Valentine leukocidin (PVL) gene as virulence factor, identification if antimicrobial sensitivity patterns, agr (accessory gene regulator) types and sequence types and in resistant cases to obtain SCCmec (staphylococcal cassette chromosome mec) gene types which will be helpful to decide empirical therapy and future health politics for S. aureus species. Total of 150 isolates of S. aureus were isolated from the cultures of the child patients in January 2011 and December 2012. In this study, the penicillin resistance was observed as 93.8%. PVL and mecA was detected positive in 8.7% and in 6% of all S. aureus strains, respectively. Two MRSA (methicillin resistant S.aureus) strains were detected as SCCmec type III and SCCmec type V and five MRSA strains were detected as SCCmec type IV. SET-I and SET-G were the most common detected enterotoxins. In both community-associated and healthcare-associated MRSA strains, agr type 1 was detected most commonly. The most common sequence types were ST737 in 13 patients than ST22 in eight patients and ST121 in six patients. This study highlights a necessity to review the cause of small changes in the structural genes in order to determine whether it is a cause or outcome; community-acquired and healthcare associated strains overlap.

  9. Diversity of 16S rRNA genes of new Ehrlichia strains isolated from horses with clinical signs of Potomac horse fever.

    PubMed

    Wen, B; Rikihisa, Y; Fuerst, P A; Chaichanasiriwithaya, W

    1995-04-01

    Ehrlichia risticii is the causative agent of Potomac horse fever. Variations among the major antigens of different local E. risticii strains have been detected previously. To further assess genetic variability in this species or species complex, the sequences of the 16S rRNA genes of several isolates obtained from sick horses diagnosed as having Potomac horse fever were determined. The sequences of six isolates obtained from Ohio and three isolates obtained from Kentucky were amplified by PCR. Three groups of sequences were identified. The sequences of five of the Ohio isolates were identical to the sequence of the type strain of E. risticii, the Illinois strain. The sequence of one Ohio isolate, isolate 081, was unique; this sequence differed in 10 nucleotides from the sequence of the type strain (level of similarity, 99.3%). The sequences of the three Kentucky isolates were identical to each other, but differed by five bases from the sequence of the type strain (level of similarity, 99.6%). The levels of sequence similarity of isolate 081, the Kentucky isolates, and the type strain to the next most closely related Ehrlichia sp., Ehrlichia sennetsu, were 99.3, 99.2, and 99.2%, respectively. On the basis of the distinct antigenic profiles and the levels of 16S rRNA sequence divergence, isolate 081 is as divergent from the type strain of E. risticii as E. sennetsu is. Therefore, we suggest that strain 081 and the Kentucky isolates may represent two new distinct Ehrlichia species.

  10. Evaluation of Fourier transform infrared (FT-IR) spectroscopy and chemometrics as a rapid approach for sub-typing Escherichia coli O157:H7 isolates.

    PubMed

    Davis, R; Paoli, G; Mauer, L J

    2012-09-01

    The importance of tracking outbreaks of foodborne illness and the emergence of new virulent subtypes of foodborne pathogens have created the need for rapid and reliable sub-typing methods for Escherichia coli O157:H7. Fourier transform infrared (FT-IR) spectroscopy coupled with multivariate statistical analyses was used for sub-typing 30 strains of E. coli O157:H7 that had previously been typed by multilocus variable number tandem repeat analysis (MLVA) and pulsed field gel electrophoresis (PFGE). Hierarchical cluster analysis (HCA) and canonical variate analysis (CVA) of the FT-IR spectra resulted in the clustering of the same or similar MLVA types and separation of different MLVA types of E. coli O157:H7. The developed FT-IR method showed better discriminatory power than PFGE in sub-typing E. coli O157:H7. Results also indicated the spectral relatedness between different outbreak strains. However, the grouping of some strains was not in complete agreement with the clustering based on PFGE and MLVA. Additionally, HCA of the spectra differentiated the strains into 30 sub-clusters, indicating the high specificity and suitability of the method for strain level identification. Strains were also classified (97% correct) based on the type of Shiga toxin present using CVA of the spectra. This study demonstrated that FT-IR spectroscopy is suitable for rapid (≤16 h) and economical sub-typing of E. coli O157:H7 with comparable accuracy to MLVA typing. This is the first report of using an FT-IR-based method for sub-typing E. coli O157:H7. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Effect of Restorative Configurations and Occlusal Schemes on Strain Levels in Bone Surrounding Implants.

    PubMed

    Block, Jonathan; Matalon, Shlomo; Tanase, Gabriela; Ormianer, Zeev

    2017-08-01

    This study investigated strain levels during and after implant insertion, and during and after simulated mastication, in splinted and nonsplinted restorations with different occlusal schemes. Fresh bovine bone resembling type I jawbone was collected. Strain gauges were placed at each implant's neck, one horizontally and one vertically. Strains at and after implant insertion were recorded. The restoration was loaded with cyclic load simulating mastication. Loading and residual strains were recorded for 6 experimental loading types. At and after implant insertion, high horizontal strains were measured. Full splint loading presented higher vertical compared with horizontal strains (P < 0.05). Segmented cross-arch splint showed higher horizontal strains (P < 0.05). Premolar loading guidance presented the most favorable loading and residual strain results (P < 0.05). Splinting implant restorations may reduce strain levels at implant neck area and provide preferable strain distribution during cyclic loading.

  12. Genetic Diversity among Clostridium botulinum Strains Harboring bont/A2 and bont/A3 Genes

    PubMed Central

    Raphael, Brian H.; Joseph, Lavin A.; Meno, Sarah R.; Fernández, Rafael A.; Maslanka, Susan E.

    2012-01-01

    Clostridium botulinum type A strains are known to be genetically diverse and widespread throughout the world. Genetic diversity studies have focused mainly on strains harboring one type A botulinum toxin gene, bont/A1, although all reported bont/A gene variants have been associated with botulism cases. Our study provides insight into the genetic diversity of C. botulinum type A strains, which contain bont/A2 (n = 42) and bont/A3 (n = 4) genes, isolated from diverse samples and geographic origins. Genetic diversity was assessed by using bont nucleotide sequencing, content analysis of the bont gene clusters, multilocus sequence typing (MLST), and pulsed-field gel electrophoresis (PFGE). Sequences of bont genes obtained in this study showed 99.9 to 100% identity with other bont/A2 or bont/A3 gene sequences available in public databases. The neurotoxin gene clusters of the subtype A2 and A3 strains analyzed in this study were similar in gene content. C. botulinum strains harboring bont/A2 and bont/A3 genes were divided into six and two MLST profiles, respectively. Four groups of strains shared a similarity of at least 95% by PFGE; the largest group included 21 out of 46 strains. The strains analyzed in this study showed relatively limited genetic diversity using either MLST or PFGE. PMID:23042179

  13. Deciphering the biodiversity of Listeria monocytogenes lineage III strains by polyphasic approaches.

    PubMed

    Zhao, Hanxin; Chen, Jianshun; Fang, Chun; Xia, Ye; Cheng, Changyong; Jiang, Lingli; Fang, Weihuan

    2011-10-01

    Listeria monocytogenes is a foodborne pathogen of humans and animals. The majority of human listeriosis cases are caused by strains of lineages I and II, while lineage III strains are rare and seldom implicated in human listeriosis. We revealed by 16S rRNA sequencing the special evolutionary status of L. monocytogenes lineage III, which falls between lineages I and II strains of L. monocytogenes and the non-pathogenic species L. innocua and L. marthii in the dendrogram. Thirteen lineage III strains were then characterized by polyphasic approaches. Biochemical reactions demonstrated 8 biotypes, internalin profiling identified 10 internal-in types clustered in 4 groups, and multilocus sequence typing differentiated 12 sequence types. These typing schemes show that lineage III strains represent the most diverse population of L. monocytogenes, and comprise at least four subpopulations IIIA-1, IIIA-2, HIB, and IIIC. The in vitro and in vivo virulence assessments showed that two lineage IIIA-2 strains had reduced pathogenicity, while the other lineage III strains had comparable virulence to lineages I and II. The HIB strains are phylogenetically distinct from other sub-populations, providing additional evidence that this sublineage represents a novel lineage. The two biochemical reactions L-rhamnose and L-lactate alkalinization, and 10 internalins were identified as potential markers for lineage III subpopulations. This study provides new insights into the biodiversity and population structure of lineage III strains, which are important for understanding the evolution of the L. mono-cytogenes-L. innocua clade.

  14. Lacinutrix chionocetis sp. nov., isolated from gut of a red snow crab.

    PubMed

    Kim, Hyangmi; Yoon, Sang-Chul; Choi, Kwang-Ho; Kim, Sung-Tae; Lee, Jae-Bong; Kim, Dong-Sun; Le Han, Ho; Bae, Kyung Sook; Park, Doo-Sang

    2017-05-01

    A Gram-negative, aerobic, non-motile, rod-shaped bacterial strain, designated MAB-07 T , was isolated from the gut of a red snow crab. The novel strain grew optimally at 20 °C, pH 7.0-8.0, and in the presence of 3% (w/v) NaCl. A phylogenetic analysis based on the 16S rRNA gene sequence indicated that the strain MAB-07 T belongs to the type strains of species of the genus Lacinutrix. Strain MAB-07 T exhibited 16S rRNA gene sequence similarity values of 95.5-97.8% with the type strains of species of the genus Lacinutrix. The predominant cellular fatty acids of strain MAB-07 T were iso-C 15:1 G (27.5%) and iso-C 15:0 (21.7%). The major respiratory quinine was identified as MK-6. The polar lipids consisted of phosphatidylethanolamine, four unidentified aminolipids, and two unidentified lipids. The genomic DNA G + C content was determined to be 33.3%, and its DNA-DNA relatedness values with the type strains of L. venerupis, L. mariniflava, L. jangbogonensis, L. algicola, and Olleya aquimaris were 28-32%. Based on the data from this polyphasic taxonomic study, strain MAB-07 T is considered to represent a novel species of the genus Lacinutrix, for which the name L. chionocetis sp. nov. is proposed. The type strain is MAB-07 T (=KCTC 42767 T  = JCM 30988 T ).

  15. Immunity status of adults and children against poliomyelitis virus type 1 strains CHAT and Sabin (LSc-2ab) in Germany.

    PubMed

    Eggers, Maren; Terletskaia-Ladwig, Elena; Rabenau, Holger F; Doerr, Hans W; Diedrich, Sabine; Enders, Gisela; Enders, Martin

    2010-12-09

    In October 2007, the working group CEN/TC 216 of the European Committee for standardisation suggested that the Sabin oral poliovirus vaccine type 1 strain (LSc-2ab) presently used for virucidal tests should be replaced by another attenuated vaccine poliovirus type 1 strain, CHAT. Both strains were historically used as oral vaccines, but the Sabin type 1 strain was acknowledged to be more attenuated. In Germany, vaccination against poliomyelitis was introduced in 1962 using the oral polio vaccine (OPV) containing Sabin strain LSc-2ab. The vaccination schedule was changed from OPV to an inactivated polio vaccine (IPV) containing wild polio virus type 1 strain Mahoney in 1998. In the present study, we assessed potential differences in neutralising antibody titres to Sabin and CHAT in persons with a history of either OPV, IPV, or OPV with IPV booster. Neutralisation poliovirus antibodies against CHAT and Sabin 1 were measured in sera of 41 adults vaccinated with OPV. Additionally, sera from 28 children less than 10 years of age and immunised with IPV only were analysed. The neutralisation assay against poliovirus was performed according to WHO guidelines. The neutralisation activity against CHAT in adults with OPV vaccination history was significantly lower than against Sabin poliovirus type 1 strains (Wilcoxon signed-rank test P < 0.025). In eight sera, the antibody titres measured against CHAT were less than 8, although the titre against Sabin 1 varied between 8 and 64. Following IPV booster, anti-CHAT antibodies increased rapidly in sera of CHAT-negative adults with OPV history. Sera from children with IPV history neutralised CHAT and Sabin 1 strains equally. The lack of neutralising antibodies against the CHAT strain in persons vaccinated with OPV might be associated with an increased risk of reinfection with the CHAT polio virus type 1, and this implies a putative risk of transmission of the virus to polio-free communities. We strongly suggest that laboratory workers who were immunised with OPV receive a booster vaccination with IPV before handling CHAT in the laboratory.

  16. Volcanic Soils as Sources of Novel CO-Oxidizing Paraburkholderia and Burkholderia: Paraburkholderia hiiakae sp. nov., Paraburkholderia metrosideri sp. nov., Paraburkholderia paradisi sp. nov., Paraburkholderia peleae sp. nov., and Burkholderia alpina sp. nov. a Member of the Burkholderia cepacia Complex

    PubMed Central

    Weber, Carolyn F.; King, Gary M.

    2017-01-01

    Previous studies showed that members of the Burkholderiales were important in the succession of aerobic, molybdenum-dependent CO oxidizing-bacteria on volcanic soils. During these studies, four isolates were obtained from Kilauea Volcano (Hawai‘i, USA); one strain was isolated from Pico de Orizaba (Mexico) during a separate study. Based on 16S rRNA gene sequence similarities, the Pico de Orizaba isolate and the isolates from Kilauea Volcano were provisionally assigned to the genera Burkholderia and Paraburkholderia, respectively. Each of the isolates possessed a form I coxL gene that encoded the catalytic subunit of carbon monoxide dehydrogenase (CODH); none of the most closely related type strains possessed coxL or oxidized CO. Genome sequences for Paraburkholderia type strains facilitated an analysis of 16S rRNA gene sequence similarities and average nucleotide identities (ANI). ANI did not exceed 95% (the recommended cutoff for species differentiation) for any of the pairwise comparisons among 27 reference strains related to the new isolates. However, since the highest 16S rRNA gene sequence similarity among this set of reference strains was 98.93%, DNA-DNA hybridizations (DDH) were performed for two isolates whose 16S rRNA gene sequence similarities with their nearest phylogenetic neighbors were 98.96 and 99.11%. In both cases DDH values were <16%. Based on multiple variables, four of the isolates represent novel species within the Paraburkholderia: Paraburkholderia hiiakae sp. nov. (type strain I2T = DSM 28029T = LMG 27952T); Paraburkholderia paradisi sp. nov. (type strain WAT = DSM 28027T = LMG 27949T); Paraburkholderia peleae sp. nov. (type strain PP52-1T = DSM 28028T = LMG 27950T); and Paraburkholderia metrosideri sp. nov. (type strain DNBP6-1T = DSM 28030T = LMG 28140T). The remaining isolate represents the first CO-oxidizing member of the Burkholderia cepacia complex: Burkholderia alpina sp. nov. (type strain PO-04-17-38T = DSM 28031T = LMG 28138T). PMID:28270796

  17. Volcanic Soils as Sources of Novel CO-Oxidizing Paraburkholderia and Burkholderia: Paraburkholderia hiiakae sp. nov., Paraburkholderia metrosideri sp. nov., Paraburkholderia paradisi sp. nov., Paraburkholderia peleae sp. nov., and Burkholderia alpina sp. nov. a Member of the Burkholderia cepacia Complex.

    PubMed

    Weber, Carolyn F; King, Gary M

    2017-01-01

    Previous studies showed that members of the Burkholderiales were important in the succession of aerobic, molybdenum-dependent CO oxidizing-bacteria on volcanic soils. During these studies, four isolates were obtained from Kilauea Volcano (Hawai'i, USA); one strain was isolated from Pico de Orizaba (Mexico) during a separate study. Based on 16S rRNA gene sequence similarities, the Pico de Orizaba isolate and the isolates from Kilauea Volcano were provisionally assigned to the genera Burkholderia and Paraburkholderia , respectively. Each of the isolates possessed a form I coxL gene that encoded the catalytic subunit of carbon monoxide dehydrogenase (CODH); none of the most closely related type strains possessed coxL or oxidized CO. Genome sequences for Paraburkholderia type strains facilitated an analysis of 16S rRNA gene sequence similarities and average nucleotide identities (ANI). ANI did not exceed 95% (the recommended cutoff for species differentiation) for any of the pairwise comparisons among 27 reference strains related to the new isolates. However, since the highest 16S rRNA gene sequence similarity among this set of reference strains was 98.93%, DNA-DNA hybridizations (DDH) were performed for two isolates whose 16S rRNA gene sequence similarities with their nearest phylogenetic neighbors were 98.96 and 99.11%. In both cases DDH values were <16%. Based on multiple variables, four of the isolates represent novel species within the Paraburkholderia : Paraburkholderia hiiakae sp. nov. (type strain I2 T = DSM 28029 T = LMG 27952 T ); Paraburkholderia paradisi sp. nov. (type strain WA T = DSM 28027 T = LMG 27949 T ); Paraburkholderia peleae sp. nov. (type strain PP52-1 T = DSM 28028 T = LMG 27950 T ); and Paraburkholderia metrosideri sp. nov. (type strain DNBP6-1 T = DSM 28030 T = LMG 28140 T ). The remaining isolate represents the first CO-oxidizing member of the Burkholderia cepacia complex: Burkholderia alpina sp. nov. (type strain PO-04-17-38 T = DSM 28031 T = LMG 28138 T ).

  18. Flow stress equations for type 304 stainless and AISI 1055 steels

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dadras, P.

    A model for stress-strain behavior under hot working conditions has been proposed. Based on experimental data, equations for the dependence of flow stress on strain, strain rate, and temperature have been developed. Application to type 304 stainless steel and AISI 1055 steel has been demonstrated.

  19. Surface changes and polymyxin interactions with a resistant strain of Klebsiella pneumoniae.

    PubMed

    Velkov, Tony; Deris, Zakuan Z; Huang, Johnny X; Azad, Mohammad A K; Butler, Mark; Sivanesan, Sivashangarie; Kaminskas, Lisa M; Dong, Yao-Da; Boyd, Ben; Baker, Mark A; Cooper, Matthew A; Nation, Roger L; Li, Jian

    2014-05-01

    This study examines the interaction of polymyxin B and colistin with the surface and outer membrane components of a susceptible and resistant strain of Klebsiella pneumoniae. The interaction between polymyxins and bacterial membrane and isolated LPS from paired wild type and polymyxin-resistant strains of K. pneumoniae were examined with N-phenyl-1-naphthylamine (NPN) uptake, fluorometric binding and thermal shift assays, lysozyme and deoxycholate sensitivity assays, and by (1)H NMR. LPS from the polymyxin-resistant strain displayed a reduced binding affinity for polymyxins B and colistin in comparison with the wild type LPS. The outer membrane NPN permeability of the resistant strain was greater compared with the susceptible strain. Polymyxin exposure enhanced the permeability of the outer membrane of the wild type strain to lysozyme and deoxycholate, whereas polymyxin concentrations up to 32 mg/ml failed to permeabilize the outer membrane of the resistant strain. Zeta potential measurements revealed that mid-logarithmic phase wild type cells exhibited a greater negative charge than the mid-logarithmic phase-resistant cells. Taken together, our findings suggest that the resistant derivative of K. pneumoniae can block the electrostatically driven first stage of polymyxin action, which thereby renders the hydrophobically driven second tier of polymyxin action on the outer membrane inconsequential.

  20. Multilocus Microsatellite Typing (MLMT) of Strains from Turkey and Cyprus Reveals a Novel Monophyletic L. donovani Sensu Lato Group

    PubMed Central

    Amro, Ahmad; Mentis, Andreas; Pratlong, Francine; Dedet, Jean-Pierre; Votypka, Jan; Volf, Petr; Ozensoy Toz, Seray; Kuhls, Katrin; Schönian, Gabriele; Soteriadou, Ketty

    2012-01-01

    Background New foci of human CL caused by strains of the Leishmania donovani (L. donovani) complex have been recently described in Cyprus and the Çukurova region in Turkey (L. infantum) situated 150 km north of Cyprus. Cypriot strains were typed by Multilocus Enzyme Electrophoresis (MLEE) using the Montpellier (MON) system as L. donovani zymodeme MON-37. However, multilocus microsatellite typing (MLMT) has shown that this zymodeme is paraphyletic; composed of distantly related genetic subgroups of different geographical origin. Consequently the origin of the Cypriot strains remained enigmatic. Methodology/Principal Findings The Cypriot strains were compared with a set of Turkish isolates obtained from a CL patient and sand fly vectors in south-east Turkey (Çukurova region; CUK strains) and from a VL patient in the south-west (Kuşadasi; EP59 strain). These Turkish strains were initially analyzed using the K26-PCR assay that discriminates MON-1 strains by their amplicon size. In line with previous DNA-based data, the strains were inferred to the L. donovani complex and characterized as non MON-1. For these strains MLEE typing revealed two novel zymodemes; L. donovani MON-309 (CUK strains) and MON-308 (EP59). A population genetic analysis of the Turkish isolates was performed using 14 hyper-variable microsatellite loci. The genotypic profiles of 68 previously analyzed L. donovani complex strains from major endemic regions were included for comparison. Population structures were inferred by combination of Bayesian model-based and distance-based approaches. MLMT placed the Turkish and Cypriot strains in a subclade of a newly discovered, genetically distinct L. infantum monophyletic group, suggesting that the Cypriot strains may originate from Turkey. Conclusion The discovery of a genetically distinct L. infantum monophyletic group in the south-eastern Mediterranean stresses the importance of species genetic characterization towards better understanding, monitoring and controlling the spread of leishmaniasis in this region. PMID:22348162

  1. Molecular typing of environmental and clinical strains of Vibrio vulnificus isolated in the northeastern USA.

    PubMed

    Reynaud, Yann; Pitchford, Steven; De Decker, Sophie; Wikfors, Gary H; Brown, Christopher L

    2013-01-01

    Vibrio vulnificus is a ubiquitous marine bacterium that is responsible for infections and some seafood-related illnesses and deaths in the United States, mainly in individuals with compromised health status in the Gulf of Mexico region. Most phylogenetic studies focus on V. vulnificus strains isolated in the southern United States, but almost no genetic data are available on northeastern bacterial isolates of clinical or environmental origin. Our goal in this study was to examine the genetic diversity of environmental strains isolated from commercially-produced oysters and in clinical strains of known pathogenicity in northeastern United States. We conducted analyses of a total of eighty-three strains of V. vulnificus, including 18 clinical strains known to be pathogenic. A polyphasic, molecular-typing approach was carried out, based upon established biotypes, vcg, CPS, 16S rRNA types and three other genes possibly associated with virulence (arylsulfatase A, mtlABC, and nanA). An established Multi Locus Sequence Typing (MLST) method was also performed. Phylogenetic analyses of these markers and MLST results produced similar patterns of clustering of strains into two main lineages (we categorized as 'LI' and 'LII'), with clinical and environmental strains clustering together in both lineages. Lineage LII was comprised primarily but not entirely of clinical bacterial isolates. Putative virulence markers were present in both clinical and environmental strains. These results suggest that some northeastern environmental strains of V. vulnificus are phylogenetically close to clinical strains and probably are capable of virulence. Further studies are necessary to assess the risk of human illness from consuming raw oysters harvested in the northeastern US.

  2. Cross-neutralization between three mumps viruses & mapping of haemagglutinin-neuraminidase (HN) epitopes.

    PubMed

    Vaidya, Sunil R; Dvivedi, Garima M; Jadhav, Santoshkumar M

    2016-01-01

    The reports from the countries where mumps vaccine is given as routine immunization suggest differences in mumps virus neutralizing antibody titres when tested with vaccine and wild type viruses. Such reports are unavailable from countries like India where mumps vaccine is not included in routine immunization. We, therefore, undertook this study to understand the cross-neutralization activity of Indian mumps viruses. By using commercial mumps IgG enzyme immunoassay (EIA) and a rapid focus reduction neutralization test (FRNT), a panel of serum samples was tested. The panel consisted of 14 acute and 14 convalescent serum samples collected during a mumps outbreak and 18 archived serum samples. Two wild types (genotypes C and G) and Leningrad-Zagreb vaccine strain (genotype N) were used for the challenge experiments and FRNT titres were determined and further compared. The HN protein sequence of three mumps viruses was analyzed for the presence of key epitopes. All serum samples effectively neutralized mumps virus wild types and a vaccine strain. However, significantly lower FRNT titres were noted to wild types than to vaccine strain (P<0.05). The comparison between EIA and FRNT results revealed 95.6 per cent agreement. No amino acid changes were seen in the epitopes in the Indian wild type strains. All potential N-linked glycosylation sites were observed in Indian strains. Good cross-neutralization activity was observed for three mumps virus strains, however, higher level of FRNT titres was detected for mumps virus vaccine strain compared to Indian wild type isolates.

  3. A Wide Variety of Clostridium perfringens Type A Food-Borne Isolates That Carry a Chromosomal cpe Gene Belong to One Multilocus Sequence Typing Cluster

    PubMed Central

    Xiao, Yinghua; Wagendorp, Arjen; Moezelaar, Roy; Abee, Tjakko

    2012-01-01

    Of 98 suspected food-borne Clostridium perfringens isolates obtained from a nationwide survey by the Food and Consumer Product Safety Authority in The Netherlands, 59 strains were identified as C. perfringens type A. Using PCR-based techniques, the cpe gene encoding enterotoxin was detected in eight isolates, showing a chromosomal location for seven isolates and a plasmid location for one isolate. Further characterization of these strains by using (GTG)5 fingerprint repetitive sequence-based PCR analysis distinguished C. perfringens from other sulfite-reducing clostridia but did not allow for differentiation between various types of C. perfringens strains. To characterize the C. perfringens strains further, multilocus sequence typing (MLST) analysis was performed on eight housekeeping genes of both enterotoxic and non-cpe isolates, and the data were combined with a previous global survey covering strains associated with food poisoning, gas gangrene, and isolates from food or healthy individuals. This revealed that the chromosomal cpe strains (food strains and isolates from food poisoning cases) belong to a distinct cluster that is significantly distant from all the other cpe plasmid-carrying and cpe-negative strains. These results suggest that different groups of C. perfringens have undergone niche specialization and that a distinct group of food isolates has specific core genome sequences. Such findings have epidemiological and evolutionary significance. Better understanding of the origin and reservoir of enterotoxic C. perfringens may allow for improved control of this organism in foods. PMID:22865060

  4. Molecular Characteristics of Erythromycin-Resistant Streptococcus pyogenes Strains Isolated from Children Patients in Tunis, Tunisia.

    PubMed

    Ksia, Sonia; Smaoui, Hanen; Hraoui, Manel; Bouafsoun, Aida; Boutiba-Ben Boubaker, Ihem; Kechrid, Amel

    2017-07-01

    The aims of our study were to characterize phenotypically and genotypically erythromycin-resistant Streptococcus pyogenes or group A streptococci (ERGAS) isolates, to evaluate macrolide resistance and to analyze the association between emm types and virulence factors. Included in this study were all ERGAS strains isolated from 2000 to 2013 at the Children's hospital of Tunis. Antimicrobial susceptibility was performed according to the CA-SFM guidelines. Macrolide resistance genes were revealed by polymerase chain reaction (PCR) method. Virulence factor genes (pyrogenic exotoxin genes and superantigen gene) were detected by PCR, and the emm types were defined by the sequencing of the variable 5' end of the emm gene. Among the 289 GAS isolates collected, 15 (5.2%) were resistant to erythromycin; 7 of the strains were assigned to the cMLS B phenotype (46.6%); 5 harbored ermB gene alone (33.3%); and 2 strains coharbored ermB and mefA (13.3%). The remaining (53.4%) were assigned to the M phenotype and harbored the mefA gene. The frequency of detection of each toxin gene among ERGAS was 13.4% for speA (2 strains), 53.4% for speC (8 strains), and 13.4% for ssa (2 strains). Emm types 1, 58, 11, and 78 were the most frequent among ERGAS strains. The distribution of the cMLS B and M phenotypes changed over the period of investigation with a decrement of cMLS B phenotype and ermB gene that predominated between 2000 and 2006 and an increase of M phenotype and mefA gene between 2007 and 2013, but this difference was nonstatistically significant because of the low number of resistant strains. Emm types 1, 58, and 4 were only present among strains assigned to the M phenotype. However strains assigned to the cMLS B phenotype were associated to emm11, emm22, emm28, emm78, or emm76. There was diversity in emm distribution in ERGAS between the two study periods. There was diversity in emm distribution among ERGAS particularly in 2000-2006. Indeed, from 2000 to 2006, the 6 ERGAS belonged to 5 different emm types (22, 28, 76, 11, and 4), while between 2007 and 2013, seven among the nine ERGAS belonged to only 2 emm types 58 and 1. The speA gene was present only among emm1 isolates, and the ssa gene was associated with emm4 and emm78 types. All emm78, emm28, and emm11 strains harbored speC gene. Our study revealed a low frequency of ERGAS and few emm types were associated with these strains.

  5. Low cycle fatigue properties of type 316 stainless steel in vacuum

    NASA Astrophysics Data System (ADS)

    Furuya, Kazuo; Nagata, Norio; Watanabe, Ryoji

    1980-04-01

    Low cycle fatigue tests in vacuum were carried out on Type 316 stainless steel under the push-pull type, strain-controlled, continuous cycling mode in the temperature range from room temperature to 1073 K and strain rate from 5 × 10 -3 to 5 × 10 -5/s . Little temperature dependence of the fatigue life at a given plastic strain range is observed. The fatigue life decreases with decreasing strain rate at room temperature and 823 K, but shows little change at 973 and 1073 K. The fracture mode is transgranular in most cases, but an indication of intergranular cracking is observed in the specimens tested at 1073 K and at the lowest strain rate. The results are treated by the general adsorption model.

  6. Genetic relatedness of ciprofloxacin-resistant Shigella dysenteriae type 1 strains isolated in south Asia.

    PubMed

    Talukder, Kaisar A; Khajanchi, Bijay K; Islam, M Aminul; Dutta, Dilip K; Islam, Zhahirul; Safa, Ashrafus; Khan, G Y; Alam, Khorshed; Hossain, M A; Malla, Sarala; Niyogi, S K; Rahman, Mustafizur; Watanabe, Haruo; Nair, G Balakrish; Sack, David A

    2004-10-01

    The aim of the present study was to determine the clonal relationships of ciprofloxacin-resistant Shigella dysenteriae type 1 strains isolated from south Asia, and S. dysenteriae 1 strains associated with epidemics in 1978, 1984 and 1994. The antimicrobial susceptibilities were examined by NCCLS methods. Molecular epidemiological characterization was performed by plasmid profiling, pulsed-field gel electrophoresis (PFGE) and mutation analysis of the quinolone resistance-determining region (QRDR) of gyrA by sequencing. Plasmid patterns of the current ciprofloxacin-resistant strains from India, Nepal and Bangladesh were very similar to those of the 1978, 1984 and 1994 epidemic isolates of S. dysenteriae 1, except for the presence of a new plasmid of approximately 2.6 MDa, which was found in one recent ciprofloxacin-resistant strain isolated in Bangladesh. PFGE analysis showed that the ciprofloxacin-resistant strains isolated in Bangladesh, India and Nepal belonged to a PFGE type (type A), which was possibly related to that of the 1984 and 1994 clone of S. dysenteriae 1, but different from 1978 epidemic strains. The current ciprofloxacin-resistant strains belong to five subtypes (A3-A7), all of which were found in India, but in Bangladesh and Nepal, only A3 existed. Mutation analysis of the QRDR of gyrA revealed that amino acid substitutions at positions 83 and 87 of ciprofloxacin-resistant strains isolated in Bangladesh were similar to those of the strains isolated in Nepal, but different (at position 87) from ciprofloxacin-resistant strains isolated in India. PFGE and mutation analysis of gyrA showed differences between the current ciprofloxacin-resistant S. dysenteriae 1 strains isolated in south Asia and those associated with epidemics in 1978, 1984 and 1994.

  7. The role of hydrodynamic stress on the phenotypic characteristics of single and binary biofilms of Pseudomonas fluorescens.

    PubMed

    Simões, M; Pereira, M O; Vieira, M J

    2007-01-01

    This study investigates the phenotype of turbulent (Re = 5,200) and laminar (Re = 2,000) flow-generated Pseudomonas fluorescens biofilms. Three P. fluorescens strains, the type strain ATCC 13525 and two strains isolated from an industrial processing plant, D3-348 and D3-350, were used throughout this study. The isolated strains were used to form single and binary biofilms. The biofilm physiology (metabolic activity, cellular density, mass, extracellular polymeric substances, structural characteristics and outer membrane proteins [OMP] expression) was compared. The results indicate that, for every situation, turbulent flow-generated biofilms were more active (p < 0.05), had more mass per cm(2) (p < 0.05), a higher cellular density (p < 0.05), distinct morphology, similar matrix proteins (p > 0.1) and identical (isolated strains -single and binary biofilms) and higher (type strain) matrix polysaccharides contents (p < 0.05) than laminar flow-generated biofilms. Flow-generated biofilms formed by the type strain revealed a considerably higher cellular density and amount of matrix polysaccharides than single and binary biofilms formed by the isolated strains (p < 0.05). Similar OMP expression was detected for the several single strains and for the binary situation, not dependent on the hydrodynamic conditions. Binary biofilms revealed an equal coexistence of the isolated strains with apparent neutral interactions. In summary, the biofilms formed by the type strain represent, apparently, the worst situation in a context of control. The results obtained clearly illustrate the importance of considering strain variation and hydrodynamics in biofilm development, and complement previous studies which have focused on physical aspects of structural and density differences.

  8. Method for enhancing the solubility of dopants in silicon

    DOEpatents

    Sadigh, Babak; Lenosky, Thomas J.; De La Rubia, Tomas Diaz

    2003-09-30

    A method for enhancing the equilibrium solid solubility of dopants in silicon, germanium and silicon-germanium alloys. The method involves subjecting silicon-based substrate to biaxial or compression strain. It has been determined that boron solubility was largely enhanced (more than 100%) by a compressive bi-axial strain, based on a size-mismatch theory since the boron atoms are smaller than the silicon atoms. It has been found that the large enhancement or mixing properties of dopants in silicon and germanium substrates is primarily governed by their, and to second order by their size-mismatch with the substrate. Further, it has been determined that the dopant solubility enhancement with strain is most effective when the charge and the size-mismatch of the impurity favor the same type of strain. Thus, the solid solubility of small p-type (e.g., boron) as well as large n-type (e.g., arsenic) dopants can be raised most dramatically by appropriate bi-axial (compressive) strain, and that solubility of a large p-type dopant (e.g, indium) in silicon will be raised due to size-mismatch with silicon, which favors tensile strain, while its negative charge prefers compressive strain, and thus the two effects counteract each other.

  9. Genotypic and Phenotypic Characteristics of Corynebacterium diphtheriae Strains Isolated from Patients in Belarus during an Epidemic Period

    PubMed Central

    Titov, Leonid; Kolodkina, Valentina; Dronina, Alina; Grimont, Francine; Grimont, Patrick A. D.; Lejay-Collin, Monique; de Zoysa, Aruni; Andronescu, Constantin; Diaconescu, Angela; Marin, Byanca; Efstratiou, Androulla

    2003-01-01

    One hundred two Corynebacterium diphtheriae strains (93 of the gravis biotype and nine of the mitis biotype) isolated from clinical cases during the Belarus diphtheria epidemic were characterized by biotyping, toxigenicity testing by the Elek test and an indirect hemagglutination assay, phage typing, and ribotyping. The gravis biotype strains were characterized as high and medium toxin producers, and strains of biotype mitis were characterized as low and medium toxin producers. Most strains (82 of 102) were distributed among five phage types. Seventy-two strains (64 of the gravis biotype and 8 of the mitis biotype) belonged to phage type VI ls5,34add. Hybridization of genomic DNA digested with BstEII and PvuII revealed five ribotype patterns, namely, D1, D4, D6, D7, and D13. The majority of gravis biotype strains belonged to ribotypes D1 (49 of 93) and D4 (33 of 93) and included one clonal group of C. diphtheriae. This clone predominated in all regions in Belarus. There was a statistical association between ribotypes and phage types but not between ribotypes and levels of toxin production. PMID:12624069

  10. Pseudomonas caspiana sp. nov., a citrus pathogen in the Pseudomonas syringae phylogenetic group.

    PubMed

    Busquets, Antonio; Gomila, Margarita; Beiki, Farid; Mulet, Magdalena; Rahimian, Heshmat; García-Valdés, Elena; Lalucat, Jorge

    2017-07-01

    In a screening by multilocus sequence analysis of Pseudomonas strains isolated from diverse origins, 4 phylogenetically closely related strains (FBF58, FBF102 T , FBF103, and FBF122) formed a well-defined cluster in the Pseudomonas syringae phylogenetic group. The strains were isolated from citrus orchards in northern Iran with disease symptoms in the leaves and stems and its pathogenicity against citrus plants was demonstrated. The whole genome of the type strain of the proposed new species (FBF102 T =CECT 9164 T =CCUG 69273 T ) was sequenced and characterized. Comparative genomics with the 14 known Pseudomonas species type strains of the P. syringae phylogenetic group demonstrated that this strain belonged to a new genomic species, different from the species described thus far. Genome analysis detected genes predicted to be involved in pathogenesis, such as an atypical type 3 secretion system and two type 6 secretion systems, together with effectors and virulence factors. A polyphasic taxonomic characterization demonstrated that the 4 plant pathogenic strains represented a new species, for which the name Pseudomonas caspiana sp. nov. is proposed. Copyright © 2017 Elsevier GmbH. All rights reserved.

  11. Histamine production by Klebsiella pneumoniae and an incident of scombroid fish poisoning.

    PubMed Central

    Taylor, S L; Guthertz, L S; Leatherwood, M; Lieber, E R

    1979-01-01

    A histamine-producing strain of Klebsiella pneumoniae was isolated from a sample of tuna sashimi implicated in an outbreak of scombroid fish poisoning. None of the other nine gram-negative bacterial strains isolated from the tuna sashimi was capable of equivalent histamine production. Bacterial histamine production was monitored in a tuna fish infusion broth (TFIB), and the implicated K. pneumoniae was capable of producing 442 mg of histamine per 100 g of tuna in TFIB in 7 h under controlled incubation conditions. Only 12 of 50 other K. pneumoniae strains, representing 5 distinct biochemical types, which had been originally isolated from foods, were able to produce such levels of histamine in TFIB. No correlation was found between histamine production and other biochemical characteristics or antibiotic resistance. Of the 12 histamine-producing strains, 11 belonged to type 2, which is characterized as indole negative with positive reactions in the urea and Voges-Proskauer tests. However, only 50% of the type 2 strains examined produced high levels of histamine in TFIB. Additionally, the implicated K. pneumoniae strain and one other strain belonged to type 1, which is characterized by positive reactions in the indole, urea, and Voges-Proskauer tests. PMID:373626

  12. Production of broad-spectrum bacteriocin-like activity by group A streptococci of particular M-types.

    PubMed

    Hynes, W L; Tagg, J R

    1985-04-01

    Application of a bacteriocin production (P)-typing scheme to group A streptococci has shown that approximately 10% of the tested strains inhibit the growth of all 9 indicator bacteria, an activity referred to as P-type 777. Production of such activity was found to be restricted to 14 M-serotypes and within these M-types the incidence of P-type 777 activity was very high. There was no evidence of any correlation with the T-antigenic composition of the bacteria. Investigations of the conditions for production of P-type 777 activity and of its spectrum of activity indicate that the same inhibitory substance(s) are responsible for this inhibition in the various M-types of streptococci. Group C streptococcus strain T277 produces an inhibitor which has a similar activity spectrum to that of the P-type 777 group A streptococci, but there were considerable differences in the production conditions. Whereas the group C inhibitor was particularly dependent on conditions of incubation (37 degrees C, anaerobic) the group A activity was more dependent on the composition of the test medium (source of blood agar base and blood requirement). All of the tested P-type 777 group A streptococci had identical inhibitory spectra. This was principally directed against gram-positive bacteria, including the producer strains themselves. Of interest was the occurrence of some insensitive strains in otherwise susceptible species of bacteria and the discovery of one sensitive gram-negative strain, Bacteroides intermedius. Production of P-type 777 activity does not appear to correlate with production of various streptococcal enzymes, including protease, hemolysin, DNase and amylase. Many P-type 777 strains are producers of opacity factor, another M-type-associated product of group A streptococci. It is suggested that by the combined testing of group A streptococci for P-type 777 activity and for opacity factor it would be possible to narrow the choice of M-antisera to be used for typing purposes.

  13. Amplicon Sequencing of the slpH Locus Permits Culture-Independent Strain Typing of Lactobacillus helveticus in Dairy Products

    PubMed Central

    Moser, Aline; Wüthrich, Daniel; Bruggmann, Rémy; Eugster-Meier, Elisabeth; Meile, Leo; Irmler, Stefan

    2017-01-01

    The advent of massive parallel sequencing technologies has opened up possibilities for the study of the bacterial diversity of ecosystems without the need for enrichment or single strain isolation. By exploiting 78 genome data-sets from Lactobacillus helveticus strains, we found that the slpH locus that encodes a putative surface layer protein displays sufficient genetic heterogeneity to be a suitable target for strain typing. Based on high-throughput slpH gene sequencing and the detection of single-base DNA sequence variations, we established a culture-independent method to assess the biodiversity of the L. helveticus strains present in fermented dairy food. When we applied the method to study the L. helveticus strain composition in 15 natural whey cultures (NWCs) that were collected at different Gruyère, a protected designation of origin (PDO) production facilities, we detected a total of 10 sequence types (STs). In addition, we monitored the development of a three-strain mix in raclette cheese for 17 weeks. PMID:28775722

  14. Administration of a Salmonella Enteritidis ΔhilAssrAfliG strain by coarse spray to newly hatched broilers reduces colonization and shedding of a Salmonella Enteritidis challenge strain.

    PubMed

    De Cort, W; Haesebrouck, F; Ducatelle, R; van Immerseel, F

    2015-01-01

    Consumption of contaminated poultry meat is still an important cause of Salmonella infections in humans. Colonization inhibition (CI) occurs when a live Salmonella strain is administered to chickens and subsequently protects against challenge with another Salmonella strain belonging to the same serotype. A Salmonella Enteritidis hilAssrAfliG deletion mutant has previously been proven to reduce colonization and shedding of a wild-type Salmonella Enteritidis strain in newly hatched broilers after experimental infection. In this study, we compared two administration routes for this strain. Administering the Salmonella Enteritidis ΔhilAssrAfliG strain through drinking water on the first day of life resulted in decreased fecal shedding and cecal colonization of a wild-type Salmonella Enteritidis challenge strain administered 24 h later using a seeder-bird model. When administering the CI strain by coarse spray on newly hatched broiler chicks, an even more pronounced reduction of cecal colonization was observed, and fecal shedding of the Salmonella Enteritidis challenge strain ceased during the course of the experiment. These data suggest that administering a Salmonella Enteritidis ΔhilAssrAfliG strain to newly hatched chicks using a coarse spray is a useful and effective method that reduces colonization and shedding of a wild-type Salmonella Enteritidis strain after early challenge. © 2014 Poultry Science Association Inc.

  15. Streptobacillus notomytis sp. nov., isolated from a spinifex hopping mouse (Notomys alexis Thomas, 1922), and emended description of Streptobacillus Levaditi et al. 1925, Eisenberg et al. 2015 emend.

    PubMed

    Eisenberg, Tobias; Glaeser, Stefanie P; Ewers, Christa; Semmler, Torsten; Nicklas, Werner; Rau, Jörg; Mauder, Norman; Hofmann, Nicola; Imaoka, Koichi; Kimura, Masanobu; Kämpfer, Peter

    2015-12-01

    A pleomorphic, Gram-negative, rod-shaped, indole-, oxidase- and catalase-negative, non-spore-forming, non-motile bacterium was isolated in 1979 from the heart of a spinifex hopping mouse (Notomys alexis Thomas, 1922) with septicaemia and stored as Streptobacillus moniliformis in the strain collection of the Animal Health Laboratory, South Perth, Western Australia (AHL 370-1), as well as under CCUG 12425. On the basis of 16SrRNA gene sequence analyses, the strain was assigned to the genus Streptobacillus, with 99.4 % sequence similarity to the type strain of Streptobacillus moniliformis, 95.6 %sequence similarity to the type strain of Streptobacillus hongkongensis and 99.0 %sequence similarity to the type strain of Streptobacillus felis. The clear differentiation of strain AHL 370-1T from Streptobacillus moniliformis, Streptobacillus hongkongensis and Streptobacillus felis was also supported by rpoB, groEL and recA nucleotide and amino acid sequence analysis. Average nucleotide identity was 87.16 % between strain AHL 370-1T and Streptobacillus moniliformis DSM 12112T. Physiological data confirmed the allocation of strain AHL 370-1T to the family Leptotrichiaceae, considering the very similar profiles of enzyme activities and fatty acids compared to closely related species. Within the genus Streptobacillus,isolate AHL 370-1T could also be separated unambiguously from the type strains of Streptobacillus moniliformis, Streptobacillus hongkongensis and Streptobacillus felis by MALDI-TOF mass spectrometry. Two further strains (KWG2 and KWG24) isolated from asymptomatic black rats in Japan were highly similar to AHL 370-1T. On the basis of these data, we propose the novel species Streptobacillus notomytis sp. nov., with the type strain AHL370-1T (=CCUG 12425T=DSM 100026T=CCM 8593T=EF 12425T).

  16. Analysis of infant isolates of Bifidobacterium breve by comparative genome hybridization indicates the existence of new subspecies with marked infant specificity.

    PubMed

    Boesten, Rolf; Schuren, Frank; Wind, Richèle D; Knol, Jan; de Vos, Willem M

    2011-09-01

    A total of 20 Bifidobacterium strains were isolated from fecal samples of 4 breast- and bottle-fed infants and all were characterized as Bifidobacterium breve based on 16S rRNA gene sequence and metabolic analysis. These isolates were further characterized and compared to the type strains of B. breve and 7 other Bifidobacterium spp. by comparative genome hybridization. For this purpose, we constructed and used a DNA-based microarray containing over 2000 randomly cloned DNA fragments from B. breve type strain LMG13208. This molecular analysis revealed a high degree of genomic variation between the isolated strains and allowed the vast majority to be grouped into 4 clusters. One cluster contained a single isolate that was virtually indistinguishable from the B. breve type strain. The 3 other clusters included 19 B. breve strains that differed considerably from all type strains. Remarkably, each of the 4 clusters included strains that were isolated from a single infant, indicating that a niche adaptation may contribute to variation within the B. breve species. Based on genomic hybridization data, the new B. breve isolates were estimated to contain approximately 60-90% of the genes of the B. breve type strain, attesting to the existence of various subspecies within the species B. breve. Further bioinformatic analysis identified several hundred diagnostic clones specific to the genomic clustering of the B. breve isolates. Molecular analysis of representatives of these revealed that annotated genes from the conserved B. breve core encoded mainly housekeeping functions, while the strain-specific genes were predicted to code for functions related to life style, such as carbohydrate metabolism and transport. This is compatible with genetic adaptation of the strains to their niche, a combination of infants and diet. Copyright © 2011 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  17. TEM Derivative-Producing Enterobacter aerogenes Strains: Dissemination of a Prevalent Clone

    PubMed Central

    Dumarche, P.; De Champs, C.; Sirot, D.; Chanal, C.; Bonnet, R.; Sirot, J.

    2002-01-01

    TEM-24 (CAZ-6) extended-spectrum β-lactamase (ESBL) was detected in 1988 in Clermont-Ferrand, France, in Klebsiella pneumoniae (blaTEM-24) and Enterobacter aerogenes (blaTEM-24b), and since 1994, a TEM-24-producing E. aerogenes clonal strain has been observed elsewhere in the country. To determine if the spread of this clonal strain was restricted to TEM-24-producing E. aerogenes strains, 84 E. aerogenes strains (non-TEM/SHV-producing strains, TEM-1- or -2-producing strains, and different ESBL-producing strains), isolated from 1988 to 1999 in Clermont-Ferrand (n = 59) and in 11 other French hospitals in 1998 (n = 25), were studied. A clonal strain was found for TEM-24- but also for TEM-3- and TEM-1- or 2-producing isolates. This study shows that there is a clonal strain dependent on acquisition of the TEM-type enzyme (TEM-24 and other TEM types). PMID:11897606

  18. Multiple Epstein-Barr virus strains in patients with infectious mononucleosis: comparison of ex vivo samples with in vitro isolates by use of heteroduplex tracking assays.

    PubMed

    Tierney, Rosemary J; Edwards, Rachel Hood; Sitki-Green, Diane; Croom-Carter, Deborah; Roy, Sushmita; Yao, Qing-Yun; Raab-Traub, Nancy; Rickinson, Alan B

    2006-01-15

    Recent work using a heteroduplex tracking assay (HTA) to identify resident viral sequences has suggested that patients with infectious mononucleosis (IM) who are undergoing primary Epstein-Barr virus (EBV) infection frequently harbor different EBV strains. Here, we examine samples from patients with IM by use of a new Epstein-Barr nuclear antigen 2 HTA alongside the established latent membrane protein 1 HTA. Coresident allelic sequences were detected in ex vivo blood and throat wash samples from 13 of 14 patients with IM; most patients carried 2 or more type 1 strains, 1 patient carried 2 type 2 strains, and 1 patient carried both virus types. In contrast, coresident strains were detected in only 2 of 14 patients by in vitro B cell transformation, despite screening >20 isolates/patient. We infer that coacquisition of multiple strains is common in patients with IM, although only 1 strain tends to be rescued in vitro; whether nonrescued strains are present in low abundance or are transformation defective remains to be determined.

  19. Characterization of thermotolerant phototrophic bacteria, Rhodoplanes tepidicaeni sp. nov. and Rhodoplanes azumiensis sp. nov., isolated from a geothermal spring.

    PubMed

    Hiraishi, Akira

    2017-12-01

    Two strains of thermotolerant phototrophic alphaproteobacteria, designated strains TUT3542 T and TUT3581 T , were isolated from sediment mud and cyanobacterial mats in a geothermal spring in Japan, respectively, and taxonomically characterized. Both the strains were budding motile rods and were able to grow at 45 °C. Phototrophically grown cells of strains TUT3542 T and TUT3581 T produced pink and brownish red cultures, respectively, and showed in vivo absorption maxima at 800, 858-859 and 892-895 nm in the near infrared region, indicating the presence of a core reaction centre and peripheral pigment complexes with bacteriochlorophyll a. The intracytoplasmic membrane system was of the lamellar type parallel to the cytoplasmic membrane. 16S rRNA gene sequence comparisons showed that strains TUT3542 T and TUT3581 T had the highest similarity level to Rhodoplanes oryazae NBRC 109406 T (99.6 %) and Rhodoplaneselegans AS130 T (99.3 %), respectively. Genomic DNA-DNA reassociation studies revealed that strains TUT3542 T and TUT3581 T had hybridization levels of less than 62 and 56 % to the type strains of all established species of the genus Rhodoplanes, respectively. The G+C contents of genomic DNA were 67.7 mol% for strain TUT3542 T and 70.4 mol% for strain TUT3581 T . Results of phenotypic studies showed that the two novel strains could be differentiated from any of the previously described Rhodoplanes species. Thus, the author proposes the names Rhodoplanes tepidicaeni sp. nov. for strain TUT3542 T and Rhodoplanes azumiensis sp. nov. for strain TUT3581 T . The type strain of Rhodoplanes tepidicaeni is TUT3542 T (=KCTC 15602 T =NBRC 112815 T ) and the type strain of Rhodoplanes azumiensis is TUT3581 T (=KCTC 15603 T =NBRC 112816 T ).

  20. The multilocus sequence typing network: mlst.net.

    PubMed

    Aanensen, David M; Spratt, Brian G

    2005-07-01

    The unambiguous characterization of strains of a pathogen is crucial for addressing questions relating to its epidemiology, population and evolutionary biology. Multilocus sequence typing (MLST), which defines strains from the sequences at seven house-keeping loci, has become the method of choice for molecular typing of many bacterial and fungal pathogens (and non-pathogens), and MLST schemes and strain databases are available for a growing number of prokaryotic and eukaryotic organisms. Sequence data are ideal for strain characterization as they are unambiguous, meaning strains can readily be compared between laboratories via the Internet. Laboratories undertaking MLST can quickly progress from sequencing the seven gene fragments to characterizing their strains and relating them to those submitted by others and to the population as a whole. We provide the gateway to a number of MLST schemes, each of which contain a set of tools for the initial characterization of strains, and methods for relating query strains to other strains of the species, including clustering based on differences in allelic profiles, phylogenetic trees based on concatenated sequences, and a recently developed method (eBURST) for identifying clonal complexes within a species and displaying the overall structure of the population. This network of MLST websites is available at http://www.mlst.net.

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