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Sample records for vi population ii

  1. II-VI semiconductor compounds

    CERN Document Server

    1993-01-01

    For condensed matter physicists and electronic engineers, this volume deals with aspects of II-VI semiconductor compounds. Areas covered include devices and applications of II-VI compounds; Co-based II-IV semi-magnetic semiconductors; and electronic structure of strained II-VI superlattices.

  2. Prevalence of Mucopolysaccharidosis Types I, II, and VI in the Pediatric and Adult Population with Carpal Tunnel Syndrome (CTS). Retrospective and Prospective Analysis of Patients Treated for CTS

    DEFF Research Database (Denmark)

    Nørmark, Mette Borch; Kjaer, Nanna; Lund, Allan Meldgaard

    2017-01-01

    BACKGROUND: We wanted to investigate whether the prevalence of mucopolysaccharidoses (MPS) I, II, and VI was higher than expected in a selected cohort of patients with carpal tunnel syndrome (CTS). CTS is a common finding in patients with MPS, and therefore we screened patients who had undergone...... surgery for CTS for undiagnosed MPS. PATIENTS AND METHODS: Patients who had been operated for CTS were found in databases from two hospitals. Furthermore, patients who had undergone surgery for CTS when under the age of 18 were retrieved from the National Patient Registry. All included patients had...... a filter paper blood spot sample taken that was subsequently analyzed enzymatically for MPS I, II, and VI. RESULTS: 425 patients were included. 402 patients tested negative in the first test. 23 had inconclusive result whereof 18 was negative in a second test. The remaining five patients had two...

  3. Role of metal d states in II-VI semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Wei, S.; Zunger, A.

    1988-05-15

    All-electron band-structure calculations and photoemission experiments on II-VI semiconductors both exhibit a metal d subband inside the main valence band. It has nevertheless been customary in pseudopotential and tight-binding approaches to neglect the metal d band by choosing Hamiltonian parameters which place this band inside the chemically inert atomic cores. Using all-electron self-consistent electronic-structure techniques (which treat the outermost d electrons on the same footing as other valence electrons) and comparing the results to those obtained by methods which remove the d band from the valence spectrum, we study their effects on valence properties. For II-VI semiconductors we find that p-d repulsion and hybridization (i) lower the band gaps, (ii) reduce the cohesive energy, (iii) increase the equilibrium lattice parameters, (iv) reduce the spin-orbit splitting, (v) alter the sign of the crystal-field splitting, (vi) increase the valence-band offset between common-anion II-VI semiconductors, and (vii) modify the charge distributions of various II-VI systems and their alloys. p-d repulsion is also shown to be responsible for the occurrence of deep Cu acceptor levels in II-VI semiconductors (compared with shallow acceptors of Zn in III-V), for the anomalously small band gaps in chalcopyrites, and for the negative exchange splitting in ferromagnetic MnTe.

  4. Chemistry of the Colloidal Group II-VI Nanocrystal Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Haitao [Univ. of California, Berkeley, CA (United States)

    2007-05-17

    In the last two decades, the field of nanoscience andnanotechnology has witnessed tremendous advancement in the synthesis andapplication of group II-VI colloidal nanocrystals. The synthesis based onhigh temperature decomposition of organometallic precursors has becomeone of the most successful methods of making group II-VI colloidalnanocrystals. This methodis first demonstrated by Bawendi and coworkersin 1993 to prepare cadmium chalcogenide colloidal quantum dots and laterextended by others to prepare other group II-VI quantum dots as well asanisotropic shaped colloidal nanocrystals, such as nanorod and tetrapod.This dissertation focuses on the chemistry of this type of nanocrystalsynthesis. The synthesis of group II-VI nanocrystals was studied bycharacterizing the molecular structures of the precursors and productsand following their time evolution in the synthesis. Based on theseresults, a mechanism was proposed to account for the 2 reaction betweenthe precursors that presumably produces monomer for the growth ofnanocrystals. Theoretical study based on density functional theorycalculations revealed the detailed free energy landscape of the precursordecomposition and monomerformation pathway. Based on the proposedreaction mechanism, a new synthetic method was designed that uses wateras a novel reagent to control the diameter and the aspect ratio of CdSeand CdS nanorods.

  5. Charge separation sensitized by advanced II-VI semiconductor nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Kelley, David F. [Univ.of California, Merced, CA (United States)

    2017-04-11

    This proposal focuses on how the composition and morphology of pure and alloyed II-VI semiconductor heterostructures control their spectroscopic and dynamical properties. The proposed research will use a combination of synthesis development, electron microscopy, time-resolved electronic spectroscopy and modeling calculations to study these nanostructures. The proposed research will examine the extent to which morphology, compression due to lattice mismatch and alloy effects can be used to tune the electron and hole energies and the spectroscopic properties of II-VI heterojunctions. It will also use synthesis, optical spectroscopy and HRTEM to examine the role of lattice mismatch and hence lattice strain in producing interfacial defects, and the extent to which defect formation can be prevented by controlling the composition profile through the particles and across the interfaces. Finally, we will study the magnitude of the surface roughness in core/shell nanostructures and the role of shell thickness variability on the inhomogeneity of interfacial charge transfer rates.

  6. Optimum pHs for Cr(VI) co-removal with nucleated Cu(II ...

    African Journals Online (AJOL)

    A compact nucleated precipitation technology using two fluidised sand columns in series was developed to pretreat model metal-plating wastewater containing high concentrations of Cu(II) and Cr(VI). Since either Cu(II) precipitation or Cr(VI) co-removal with Cu(II) precipitation was found to be highly pH dependent in batch ...

  7. High efficiency green LEDs using II-VI color converters

    Science.gov (United States)

    Miller, Thomas J.; Haase, Michael A.; Sun, Xiaoguang; Hao, Bing; Zhang, Junying; Smith, Terry L.; Ballen, Todd; Xie, Junqing; Barnes, Amy S.; Kecman, Fedja; Yang, Joseph; Thielen, James; Leatherdale, Catherine A.; Wirth, Ralph; Biebersdorf, Andreas; Engl, Karl; Groetsch, Stefan

    2010-02-01

    II-VI semiconductors can exhibit strong photoluminescence throughout the visible spectrum and are excellent candidates for filling the so-called "green gap". We report on the performance of green color-converted LEDs fabricated by bonding CdMgZnSe multiple quantum well structures to high-efficiency blue-emitting GaInN LEDs. A device efficacy of 181 lm/W at 537 nm (dominant) is measured under room temperature, 350 mA/mm2 quasi-cw conditions, more than twice as efficient as typical commercial green LEDs today. The thermal roll-off is shown to be comparable to that of typical green GaInN LEDs. Finally, the implications of the availability of high-efficiency, narrow-band, green and yellow emitters in display applications will be discussed.

  8. 77 FR 27081 - II-VI, Incorporated, Infrared Optics-Saxonburg Division, Saxonburg, Pennsylvania; Notice of...

    Science.gov (United States)

    2012-05-08

    ... Employment and Training Administration II-VI, Incorporated, Infrared Optics--Saxonburg Division, Saxonburg... former workers of II-VI, Incorporated, Infrared Optics--Saxonburg Division, Saxonburg, Pennsylvania... employment related to the production of infrared and CO 2 laser optics, and related materials. The initial...

  9. Kinetics and Products of Chromium(VI) Reduction by Iron(II/III)-Bearing Clay Minerals.

    Science.gov (United States)

    Joe-Wong, Claresta; Brown, Gordon E; Maher, Kate

    2017-09-05

    Hexavalent chromium is a water-soluble pollutant, the mobility of which can be controlled by reduction of Cr(VI) to less soluble, environmentally benign Cr(III). Iron(II/III)-bearing clay minerals are widespread potential reductants of Cr(VI), but the kinetics and pathways of Cr(VI) reduction by such clay minerals are poorly understood. We reacted aqueous Cr(VI) with two abiotically reduced clay minerals: an Fe-poor montmorillonite and an Fe-rich nontronite. The effects of ionic strength, pH, total Fe content, and the fraction of reduced structural Fe(II) [Fe(II)/Fe(total)] were examined. The last variable had the largest effect on Cr(VI) reduction kinetics: for both clay minerals, the rate constant of Cr(VI) reduction varies by more than 3 orders of magnitude with Fe(II)/Fe(total) and is described by a linear free energy relationship. Under all conditions examined, Cr and Fe K-edge X-ray absorption near-edge structure spectra show that the main Cr-bearing product is a Cr(III)-hydroxide and that Fe remains in the clay structure after reacting with Cr(VI). This study helps to quantify our understanding of the kinetics of Cr(VI) reduction by Fe(II/III)-bearing clay minerals and may improve predictions of Cr(VI) behavior in subsurface environments.

  10. Radiation effects on II-VI compound-based detectors

    CERN Document Server

    Cavallini, A; Dusi, W; Auricchio, N; Chirco, P; Zanarini, M; Siffert, P; Fougeres, P

    2002-01-01

    The performance of room temperature CdTe and CdZnTe detectors exposed to a radiation source can be strongly altered by the interaction of the ionizing particles and the material. Up to now, few experimental data are available on the response of II-VI compound detectors to different types of radiation sources. We have carried out a thorough investigation on the effects of gamma-rays, neutrons and electron irradiation both on CdTe : Cl and Cd sub 0 sub . sub 9 Zn sub 0 sub . sub 1 Te detectors. We have studied the detector response after radiation exposure by means of dark current measurements and of quantitative spectroscopic analyses at low and medium energies. The deep traps present in the material have been characterized by means of PICTS (photo-induced current transient spectroscopy) analyses, which allow to determine the trap apparent activation energy and capture cross-section. The evolution of the trap parameters with increasing irradiation doses has been monitored for all the different types of radiati...

  11. Multi-crystalline II-VI based multijunction solar cells and modules

    Energy Technology Data Exchange (ETDEWEB)

    Hardin, Brian E.; Connor, Stephen T.; Groves, James R.; Peters, Craig H.

    2015-06-30

    Multi-crystalline group II-VI solar cells and methods for fabrication of same are disclosed herein. A multi-crystalline group II-VI solar cell includes a first photovoltaic sub-cell comprising silicon, a tunnel junction, and a multi-crystalline second photovoltaic sub-cell. A plurality of the multi-crystalline group II-VI solar cells can be interconnected to form low cost, high throughput flat panel, low light concentration, and/or medium light concentration photovoltaic modules or devices.

  12. Biosorption of Cr(VI), Ni(II) and Fe(II) by maize ( zea mays ) cob ...

    African Journals Online (AJOL)

    The experimental results for the biosorption of Cr(VI), Ni(II) and Fe(II) onto maize cob were reported. The adsorbents efficiency on the bioremediation of these metals was estimated from the change in the percent adsorbate removal with (i) adsorbent dosage (ii) adsorbate initial concentration, (iii) variation in pH of the ...

  13. Social Set Visualizer (SoSeVi) II

    DEFF Research Database (Denmark)

    Flesch, Benjamin; Vatrapu, Ravi

    2016-01-01

    This paper reports the second iteration of the Social Set Visualizer (SoSeVi), a set theoretical visual analytics dashboard of big social data. In order to further demonstrate its usefulness in large-scale visual analytics tasks of individual and collective behavior of actors in social networks...

  14. Competitive Adsorption of Cd(II), Cr(VI), and Pb(II) onto Nanomaghemite: A Spectroscopic and Modeling Approach.

    Science.gov (United States)

    Komárek, Michael; Koretsky, Carla M; Stephen, Krishna J; Alessi, Daniel S; Chrastný, Vladislav

    2015-11-03

    A combined modeling and spectroscopic approach is used to describe Cd(II), Cr(VI), and Pb(II) adsorption onto nanomaghemite and nanomaghemite coated quartz. A pseudo-second order kinetic model fitted the adsorption data well. The sorption capacity of nanomaghemite was evaluated using a Langmuir isotherm model, and a diffuse double layer surface complexation model (DLM) was developed to describe metal adsorption. Adsorption mechanisms were assessed using X-ray photoelectron spectroscopy and X-ray absorption spectroscopy. Pb(II) adsorption occurs mainly via formation of inner-sphere complexes, whereas Cr(VI) likely adsorbs mainly as outer-sphere complexes and Cd(II) as a mixture of inner- and outer-sphere complexes. The simple DLM describes well the pH-dependence of single adsorption edges. However, it fails to adequately capture metal adsorption behavior over broad ranges of ionic strength or metal-loading on the sorbents. For systems with equimolar concentrations of Pb(II), Cd(II), and Cr(VI). Pb(II) adsorption was reasonably well predicted by the DLM, but predictions were poorer for Cr(VI) and Cd(II). This study demonstrates that a simple DLM can describe well the adsorption of the studied metals in mixed sorbate-sorbent systems, but only under narrow ranges of ionic strength or metal loading. The results also highlight the sorption potential of nanomaghemite for metals in complex systems.

  15. Heterojunctions Based on II-VI Compound Semiconductor One-Dimensional Nanostructures and Their Optoelectronic Applications

    Directory of Open Access Journals (Sweden)

    Xiwei Zhang

    2017-10-01

    Full Text Available Wide band gap II-VI semiconductor nanostructures have been extensively studied according to their great potentials for optoelectronic applications, while heterojunctions are fundamental elements for modern electronic and optoelectronic devices. Subsequently, a great deal of achievements in construction and optoelectronic applications of heterojunctions based on II-VI compound semiconductor one-dimensional nanostructures have been obtained in the past decade. Herein, we present a review of a series of progress in this field. First, construction strategies towards different types of heterojunctions are reviewed, including core-shell heterojunctions, one-dimensional axial heterojunctions, crossed nanowires heterojunctions, and one-dimensional nanostructure/thin film or Si substrate heterojunctions. Secondly, optoelectronic applications of these constructed heterojunctions, such as photodetectors, solar cells, light emitting diodes, junction field effect transistors, etc., are discussed briefly. This review shows that heterojunctions based on II-VI compound semiconductor 1-D nanostructures have great potential for future optoelectronic applications.

  16. Influence of nickel (II) and chromium (VI) on the laboratory scale rotating biological contactor.

    Science.gov (United States)

    Taşeli, B K; Gökçay, C F; Gürol, A

    2008-09-01

    High concentration of heavy metals is toxic for most microorganisms and cause strict damage in wastewater treatment operations and often a physico-chemical pretreatment prior to biological treatment is considered necessary. However, in this study it has been shown that biological systems can adapt to Ni (II) and Cr (VI) when their concentration is below 10 and 20 mg/L, respectively. The aim of this study was to evaluate the effect of Ni (II) and Cr (VI) on the lab-scale rotating biological contactor process. It was found that, addition of Ni (II) up to 10 mg/L did not reduce the chemical oxygen demand removal efficiency and on the contrary concentrations below 10 mg/L improved the performance. The influent Ni (II) concentration of 1 mg/L was the concentration where the treatment efficiency produced a maximum COD removal of 86.5%. Moreover, Ni (II) concentration above 10 mg/L was relatively toxic to the system and produced lower treatment efficiencies than the baseline study without Ni (II). Turbidity and suspended solids removals were not stimulated to a great extent with nickel. Addition of Ni (II) did not seem to affect the pH of the system during treatment. The dissolved oxygen concentration did not drop below 4 mg/L at all concentrations of Ni (II) indicating aerobic conditions prevailed in the system. Experiments conducted with Cr (VI) revealed that addition of Cr (VI) up to 20 mg/L did not reduce the COD removal efficiency and on the contrary concentrations below 20 mg/L improved the performance. The influent Cr (VI) concentration of 1 mg/L was the concentration where the treatment efficiency produced a maximum COD removal of 88%. Turbidity and SS removals were more efficient at 5 mg/L Cr (VI) concentration, rather than 1 mg/L, which lead to the conclusion that 5 mg/L Cr (VI) concentration is the optimum concentration, in terms of COD, turbidity and SS removals. Similar with Ni (II) experiments, addition of Cr (VI) did not significantly affect the pH value of

  17. Reduction process of Cr(VI) by Fe(II) and humic acid analyzed using high time resolution XAFS analysis.

    Science.gov (United States)

    Hori, Mayumi; Shozugawa, Katsumi; Matsuo, Motoyuki

    2015-03-21

    The initial reduction behavior of Cr(VI) to Cr(III) has not been clearly understood due to its rapid reduction reaction. In order to study the reduction process of Cr(VI) in detail, we applied quick X-ray absorption fine structure (QXAFS) analysis to observe how Cr(VI) was reduced to Cr(III) by Fe(II) and humic acid (HA) with time. The Cr(VI) concentration was analyzed every 60s, and the plots of ln(Cr(VI)/Cr(VI)0) versus time were used to evaluate the reduction process based on their linearity. Reduction by Fe(II) showed a linear relation, whereas reduction by HA showed a nonlinear relation. With combined Fe(II) and HA, the linearity was unlike those of Fe(II) and HA individually. The reduction rate was not constant. The structure of Fe(II) produced by HA during the Cr(VI) reduction was investigated by using Mössbauer spectroscopy, which showed that Fe(II) produced by HA reduction of Fe(III) had the same structure as the initial Fe(II). HA can reduce Fe(III) back to Fe(II), and reproduced Fe(II) reduces Cr(VI). For Cr(VI) reduction by combined Fe(II) and HA, each reductant contribute differently: Fe(II) directly contributes to the Cr(VI) reaction, whereas HA reduces both Cr(VI) and Fe(III). Copyright © 2014 Elsevier B.V. All rights reserved.

  18. 77 FR 21586 - II-VI, Incorporated, Infrared Optics-Saxonburg Division, Saxonburg, PA; Notice of Affirmative...

    Science.gov (United States)

    2012-04-10

    ... Employment and Training Administration II-VI, Incorporated, Infrared Optics--Saxonburg Division, Saxonburg... former workers of II-VI, Incorporated, Infrared Optics--Saxonburg Division, Saxonburg, Pennsylvania... employment related to the production of infrared and CO 2 laser optics, and related materials. The initial...

  19. 77 FR 36579 - II-VI, Inc., Infrared Optics-Saxonburg Division, Saxonburg, PA; Leased Workers From Adecco, Carol...

    Science.gov (United States)

    2012-06-19

    ... Employment and Training Administration II-VI, Inc., Infrared Optics-Saxonburg Division, Saxonburg, PA; Leased...., Infrared Optics-Saxonburg Division, Saxonburg, PA; Notice of Revised Determination on Reconsideration The... period. The determination was applicable to workers and former workers of II-VI, Inc., Infrared Optics...

  20. The Reaction between Iron(II) Iodide and Potassium Dichromate(VI) in Acidified Aqueous Solution

    Science.gov (United States)

    Talbot, Christopher

    2013-01-01

    This "Science note" teaching lesson explores the possible reaction between the ions in a reaction mixture consisting of iron(II) iodide and potassium dichromate(VI) in acidified aqueous solution. The electrode potentials will be used to deduce any spontaneous reactions under standard thermodynamic conditions (298 K, 1 bar (approximately…

  1. Adsorption of Cu(II) and Cr(VI) ions by chitosan: Kinetics and ...

    African Journals Online (AJOL)

    drinie

    2001-01-01

    Jan 1, 2001 ... Current treatment for the removal of Cr. (VI) involves acid catalysed chemical reduction to Cr3+. The Cr3+ is then precipitated as hydroxide at alkaline conditions using either caustic or lime (Udaybhaskar et al., 1990). The presence of Cu (II) in wastewater is also a problem. Copper is used extensively by.

  2. Correlation of Thermodynamic Properties with Structure , Bonding & Physical of Groups II-VI Compounds

    OpenAIRE

    Nasar, A; Shamsuddin, M

    2000-01-01

    Thermodynamic properties of groups II-VI compounds have been  discussed in the light of their structure, bonding, ionicity, energy gap, bond length, molecular weight, etc. An attempt has also been made to correlate various thermodynamic and physical properties of the compounds. The interrelationship between thermodynamic and physical properties have been discussed, wherever possible, with realistic justification.

  3. High-field Faraday rotation in II-VI-based semimagnetic semiconductors

    NARCIS (Netherlands)

    Savchuk, AI; Fediv, [No Value; Nikitin, PI; Perrone, A; Tatzenko, OM; Platonov, VV

    The effects of d-d exchange interaction have been studied by measuring high-field Faraday rotation in II-VI-based semimagnetic semiconductors. For Cd1-xMnxTe crystals with x = 0.43 and at room temperature a saturation in magnetic field dependence of the Faraday rotation has been observed. In the

  4. Adsorption Process and Mechanism of Cd(Ii and Cr(Vi Removal from Aqueous Solution by Waste Marigold Flowers

    Directory of Open Access Journals (Sweden)

    Monoj Kumar Mondal

    2015-12-01

    Full Text Available In this work, waste marigold flowers from Temple were used as adsorbent to remove cadmium (II and chromium (VI ions from aqueous solutions. Influences of initial heavy metal concentrations, contact time, adsorbent dose, temperature and initial pH on removal of cadmium (II and chromium (VI ions were studied under batch mode of operation. Both the adsorption process of cadmium (II and chromium (VI followed pseudo-second order kinetics. Adsorption isotherm parameters of cadmium (II and chromium (VI on dried marigold flower were determined using Langmuir and Freundlich models. Thermodynamic parameters depicted that the process was spontaneous and exothermic under experimental conditions. The maximum removal efficiency of cadmium (II was obtained as 83% at contact time 75 min and pH 5. The maximum removal efficiency of chromium (VI was found as 96% at contact time 105 min and pH 3. Dried marigold flower showed active reusability characteristics upto three consecutive adsorption-desorption cycles.

  5. Atomic models for anionic ligand passivation of cation-rich surfaces of IV-VI, II-VI, and III-V colloidal quantum dots.

    Science.gov (United States)

    Ko, Jae-Hyeon; Yoo, Dongsuk; Kim, Yong-Hyun

    2016-12-22

    We formulated atomic models of cation-rich surfaces passivated with anionic ligands for IV-VI, II-VI, and III-V colloidal quantum dots, employing electron counting models and quantum mechanical calculations. We found that the fractional dangling bonds of cation-rich (100) and (111) surfaces could be greatly stabilized by dimerization-anion passivation and amine-anion co-passivation.

  6. Military Aerospace. Aerospace Education II. Instructional Unit VI.

    Science.gov (United States)

    Hall, Arthur D.

    This curriculum guide is prepared for the Aerospace Education II series publication entitled "Military Aerospace." Sections in the guide include objectives (traditional and behavioral), suggested outline, orientation, suggested key points, suggestions for teaching, instructional aids, projects, and further reading. A separate sheet is…

  7. Multinary I-III-VI2 and I2-II-IV-VI4 Semiconductor Nanostructures for Photocatalytic Applications.

    Science.gov (United States)

    Regulacio, Michelle D; Han, Ming-Yong

    2016-03-15

    are the multinary chalcogenide semiconductors (MCSs), which include the ternary I-III-VI2 semiconductors (e.g., AgGaS2, CuInS2, and CuInSe2) and the quaternary I2-II-IV-VI4 semiconductors (e.g., Cu2ZnGeS4, Cu2ZnSnS4, and Ag2ZnSnS4). These inorganic compounds consist of environmentally benign elemental components, exhibit excellent light-harvesting properties, and possess band gap energies that are well-suited for solar photon absorption. Moreover, the band structures of these materials can be conveniently modified through alloying to boost their ability to harvest visible photons. In this Account, we provide a summary of recent research on the use of ternary I-III-VI2 and quaternary I2-II-IV-VI4 semiconductor nanostructures for light-induced photocatalytic applications, with focus on hydrogen production and organic dye degradation. We include a review of the solution-based methods that have been employed to prepare multinary chalcogenide semiconductor nanostructures of varying compositions, sizes, shapes, and crystal structures, which are factors that are known to have significant influence on the photocatalytic activity of semiconductor photocatalysts. The enhancement of photocatalytic performance through creation of hybrid nanoscale architectures is also presented. Lastly, views on the current challenges and future directions are discussed in the concluding section.

  8. In vitro evaluation of bioremediation capacity of a commercial probiotic, Bacillus coagulans, for chromium (VI and lead (II toxicity

    Directory of Open Access Journals (Sweden)

    Pranoti Belapurkar

    2016-01-01

    Full Text Available Introduction: The bioaccumulation of heavy metals including chromium (VI (Cr (VI and lead (II (Pb (II causes fatal toxicity in humans. Some naturally occurring bacterial genera such as Bacillus and Pseudomonas help in bioremediation of these heavy metals and some of the species of Bacillus are proven probiotics. However, no study has been conducted on Bacillus coagulans, which is a proven probiotic species of genus Bacillus. Objectives: The primary objective of the present study was to assess the potential of a proven probiotic, B. coagulans, marketed as “Sporlac-DS,” to survive in the presence of Cr (VI and Pb (II and its ability to reduce its concentration in vitro. Materials and Methods: The Minimum inhibitory concentration (MIC of the organism for Cr (VI and Pb (II was determined followed by its biochemical and morphological characterization. Its antibiotic sensitivity and probiotic efficacy were assessed. Further, its bioremediation capacity was observed in vitro by determining the residual Cr (VI and Pb (II concentration after 72 h. Results: B. coagulans could tolerate up to 512 ppm concentration of Cr (VI and had an MIC of 128 ppm for Pb (II. After 72 h, the organism reduced 32 ppm Cr (VI and 64 ppm Pb (II by 93% and 89%, respectively. When B. coagulans was studied before and after growing on Cr (VI and Pb (II for 24 h, an increase was seen in sensitivity toward the tested antibiotics whereas no change was observed in morphological and biochemical characters. It also showed no change in their bile and acid tolerance, indicating that it retains its probiotic efficacy. Conclusion: The tested probiotic B. coagulans may have a potential role in bioremediation of Cr (VI and Pb (II, in vivo.

  9. Biosorption of copper(II and chromium(VI by modified tea fungus

    Directory of Open Access Journals (Sweden)

    Šćiban Marina B.

    2012-01-01

    Full Text Available The tea fungus was found to have good adsorption capacities for heavy metal ions. In this work it was treated with HCl or NaOH at 20°C or 100°C, with the aim to improve its adsorption ability. The sorption of Cu(II and Cr(VI ions from aqueous solutions by raw and treated tea fungus was investigated in the batch mode. The largest quantity of adsorbed Cu(II, of about 55 mg/g, was achieved by tea fungus modified with NaOH at 100°C. For Cr(VI, the largest quantity of adsorbed anions, of about 58 mg/g, was achieved by the adsorbent modified with NaOH at 20°C. It was shown that acid modification of tea fungus biomass was not effective. [Projekat Ministarstva nauke Republike Srbije, br. III 43005 i br. TR 31002

  10. Isothermal close space sublimation for II-VI semiconductor filling of porous matrices

    Science.gov (United States)

    2012-01-01

    Isothermal close space sublimation, a simple and low-cost physical vapour transport technique, was used to infiltrate ZnTe and CdSe semiconductors in porous silicon. The structure of the embedded materials was determined by X-ray diffraction analysis while Rutherford backscattering spectra allowed determining the composition profiles of the samples. In both cases, a constant composition of the II-VI semiconductors throughout the porous layer down to the substrate was found. Resonance Raman scattering of the ZnTe samples indicates that this semiconductor grows in nanostructured form inside the pores. Results presented in this paper suggest that isothermal close space sublimation is a promising technique for the conformal growth of II-VI semiconductors in porous silicon. PMID:22823959

  11. Donor impurity incorporation during layer growth of Zn II-VI semiconductors

    Science.gov (United States)

    Barlow, D. A.

    2017-12-01

    The maximum halogen donor concentration in Zn II-VI semiconductors during layer growth is studied using a standard model from statistical mechanics. Here the driving force for incorporation is an increase in entropy upon mixing of the donor impurity into the available anion lattice sites in the host binary. A formation energy opposes this increase and thus equilibrium is attained at some maximum concentration. Considering the halogen donor impurities within the Zn II-VI binary semiconductors ZnO, ZnS, ZnSe and ZnTe, a heat of reaction obtained from reported diatomic bond strengths is shown to be directly proportional to the log of maximum donor concentration. The formation energy can then be estimated and an expression for maximum donor concentration derived. Values for the maximum donor concentration with each of the halogen impurities, within the Zn II-VI compounds, are computed. This model predicts that the halogens will serve as electron donors in these compounds in order of increasing effectiveness as: F, Br, I, Cl. Finally, this result is taken to be equivalent to an alternative model where donor concentration depends upon impurity diffusion and the conduction band energy shift due to a depletion region at the growing crystal's surface. From this, we are able to estimate the diffusion activation energy for each of the impurities mentioned above. Comparisons are made with reported values and relevant conclusions presented.

  12. Synthesis, characterization and biological activities of Cu(II), Co(II), Mn(II), Fe(II), and UO2(VI) complexes with a new Schiff Base hydrazone: O-hydroxyacetophenone-7-chloro-4-quinoline hydrazone

    National Research Council Canada - National Science Library

    Al-Shaalan, Nora H

    2011-01-01

    .... This was accounted for be the presence in the ligand of a phenolic azomethine and imine groups. It reacts with Cu(II), Ni(II), Co(II), Mn(II), UO(2) (VI) and Fe(II) to form either mono- or binuclear complexes...

  13. Genetic studies in the radioresistant RoeVI population of Drosophilia melanogaster. Genetische Untersuchung an der strahlenresistenten Population RoeVI von Drosophila melanogaster

    Energy Technology Data Exchange (ETDEWEB)

    Graetschel, G.

    1982-10-05

    The study described here was carried out in the RoeVI population of Drosophilia melanogaster, a captivity-bred group of animals raised to produce radioresistant offspring, as well as in the original Berlin-wild +S population and a further few radioresistant populations (RoeI{sub 2}, RoeI{sub 40}, RoeI{sub 41}, RoeI{sub 42}). A relative resistance to radiation of the RoeVI population could first be detected after some 50 generations had been raised. This resistance is owing to one particular factor in the distal part of the left branch of chromosome no. 3. This factor is of a dominant nature and acts to reduce the number of induced lethal factors that are also dominant. It influences the radiosensitivity of immature oocytes, although any such effects in males can definitely by ruled out. Experiments carried out to determine the extent of enzyme polymorphism in radioresistant populations subjected to different methods of irradiation did not point to any notable variability here. The latter was lower than that observed for natural populations not subjected to irradiation. One enzyme was associated with markedly pronounced frequency changes to the favour of one specific allele, which was the almost genuine allele of {alpha}-glycerophosphate dehydrogenase ({alpha}-GPDH). It remains to be investigated whether this may be of any value for further selection processes. Studies into the extent of eye colour polymorphism pointed to an increased variability in the RoeVI population as compared to the wild +S population. The higher frequency of mutants with white eyes is thought to be attributable to the heterosis brought about by the induced white-allele. The specific problems associated with relative radio-resistance are discussed for the Rer-3 factor investigated here and the related genetic changes regarding phenotype and population characteristics. (orig./MG).

  14. Optical investigations and control of spindynamics in Mn doped II-VI quantum dots; Optische Untersuchung und Kontrolle der Spindynamik in Mn dotierten II-VI Quantenpunkten

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Thomas

    2009-05-13

    The present thesis deals with the spin of charge carriers confined in CdSe/ZnSe quantum dots (QDs) closely linked to the polarization of emitted photons. II-VI material systems can be adequately mixed with the B-group element manganese. Such semimagnetic nanostructures offer a number of characteristic optical and electronic features. This is caused by an exchange interaction between the spin of optically excited carriers and the 3d electrons of the Mn ions. Within the framework of this thesis addressing of well defined spin states was realized by optical excitation of charge carriers. The occupation of different spin states was detected by the degree of polarization of the emitted photoluminescence (PL) light. For that purpose different optical methods of time-resolved and time-integrated spectroscopy as well as investigations in magnetic fields were applied. (orig.)

  15. Adsorption of Cu (II), Pb (II) and Cr (VI) from aqueous solutions using black wattle tannin-immobilized nanocellulose.

    Science.gov (United States)

    Xu, Qinghua; Wang, Yulu; Jin, Liqiang; Wang, Yu; Qin, Menghua

    2017-10-05

    A novel nanocomposite based on black wattle (BW) tannin and nanocellulose was prepared and applied in heavy metal ions adsorptive removal from aqueous solutions. Firstly, nanocrystalline cellulose was oxidized by sodium periodate to get dialdehyde nanocellulose (DANC). BW tannin was then covalently immobilized onto DANC, which was used as both the matrix and crosslinker, to obtain tannin-nanocellulose (TNCC) composite. The resulting nanocomposite was characterized using FTIR, AFM, and TG. The successful immobilization was confirmed by the chromogenic reaction between FeCl3 and TNCC and FT-IR analysis. AFM images revealed that TNCC was ellipsoidal particles with lengths ranging from 100-400nm. Zeta potential measurement showed that TNCC was negative charged at a pH range from 1-12. Compared to the original tannin, the thermal stability of TNCC was slightly increased by the addition of nanocellulose. TNCC demonstrated the maximum adsorption efficiency at pH2 for Cr(VI) and pH 6 for Cu(II) and Pb(II), respectively. The adsorption for these three metal ions followed pseudo second-order kinetics, indicating the chemisorption nature. The adsorption isotherms all fitted well with the Sips model, and the calculated maximum adsorption capacities were 51.846mgg(-1), 53.371mgg(-1) and 104.592mgg(-1) for Cu(II), Pb(II) and Cr (VI), respectively. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Comparative and competitive adsorption of Cr(VI), As(III), and Ni(II) onto coconut charcoal.

    Science.gov (United States)

    Wu, Yunhai; Wen, Yajun; Zhou, Jianxin; Cao, Julin; Jin, Yanping; Wu, Yunying

    2013-04-01

    This study evaluates the behavior of coconut charcoal (AC) to adsorb Cr(VI), As(III), and Ni(II) in mono- and multicomponent (binary and ternary) systems. Batch experiments were carried out for mono- and multicomponent systems with varying metal ion concentrations to investigate the competitive adsorption characteristics. The adsorption kinetics followed the mechanism of the pseudo-second-order equation in both single and binary systems, indicating chemical sorption as the rate-limiting step of adsorption mechanism. Equilibrium studies showed that the adsorption of Cr(VI), As(III), and Ni(II) followed the Langmuir model and maximum adsorption capacities were found to be 5.257, 0.042, and 1.748 mg/g, respectively. In multicomponent system, As(III) and Ni(II) adsorption competed intensely, while Cr(VI) adsorption was much less affected by competition than As(III) and Ni(II). With the presence of Cr(VI), the adsorption capacities of As(III) and Ni(II) on AC were higher than those in single system and the metal sorption followed the order of Ni(II) > As(III) > Cr(VI). The results from the sequential adsorption-desorption cycles showed that AC adsorbent held good desorption and reusability.

  17. Redox polymer as an adsorbent for the removal of chromium (VI and lead (II from the tannery effluents

    Directory of Open Access Journals (Sweden)

    V. Vetriselvi

    2015-06-01

    Full Text Available Polymer-based hybrid was widely fabricated and applied in heavy metal removal and other inorganic pollutants. The present study deals with the sorption efficiency of metal adsorption through the chemically modified PAA with dihydroxybenzenes into the polymeric matrix present in the tannery effluents and a parallel investigation of chromium (VI ions in aqueous solution was carried out. From the Langmuir model the removal of chromium (VI has the maximum adsorption capacity with 181.4 mg g−1. Batch sorption to remove chromium (VI and lead (II from the tannery effluents was investigated by using different parameters. The sorption efficiency was found to be 75% and 99% for chromium (VI and lead (II, respectively, present in the tannery effluents. The chemical and structural characteristics of the adsorbents were determined by UV, FT-IR, TGA, DSC, XRD and SEM-EDS analyses.

  18. Biosorption of Cr(III), Cr(VI), Cu(II) ions by intact cells of Spirulina platensis

    OpenAIRE

    Gelagutashvili, E.; Bagdavadze, N.; Rcheulishvili, A.

    2017-01-01

    The absorption characteristics of Cr(III), Cr(VI), Cu(II) ions on intact living cells Spirulina platensis (pH9.6) were studied by using a UV-VIS spectrophotometer. Also biosorption of these ions with cyanobacteria Spirulina platensis were studied using equilibrium dialysis and atomic absorption analysis.It was shown, that the absorption intensity of Spirulina platensis decreases, when Cr(III), Cr(VI), Cu(II) ions are added. Significant difference between the absorption intensity for Cu(II) Sp...

  19. The band gap of II-Vi ternary alloys in a tight-binding description

    Energy Technology Data Exchange (ETDEWEB)

    Olguin, Daniel; Blanquero, Rafael [Instituto Politecnico Nacional, Mexico, D.F (Mexico); De Coss, Romeo [Instituto Politecnico Nacional, Yucatan (Mexico)

    2001-02-01

    We present tight-binding calculations for the band gap of II-Vi pseudobinary ternary alloys. We use an sp{sup 3} s* tight-binding Hamiltonian which include spin-orbit coupling. The band gap composition dependence is calculated using a extended version of the virtual crystal approximation, which introduce an empirical correction factor that takes into account the non-linear dependence of the band gap with the composition. The results compare quite well with the experimental data, both for the ternary alloys with wide band gap and for the narrow band gap ones. [Spanish] Presentamos el calculo de la banda de energia prohibida de aleaciones ternarias de compuestos II-VI. El calculo, que incluye interaccion espin-orbita, se hace con el metodo de enlace fuerte, utilizando una base ortogonal de cinco orbitales atomicos por atomo (sp{sup 3} s*), en conjunto con la aproximacion del cristal virtual. En la aproximacion del cristal virtual, incluimos un factor de correccion que toma en cuenta la no linealidad de la banda de energia prohibida como funcion de la concentracion. Con esta correccion nuestros resultados reproducen aceptablemente los datos experimentales hallados en la literatura.

  20. Growth of Wide Band Gap II-VI Compound Semiconductors by Physical Vapor Transport

    Science.gov (United States)

    Su, Ching-Hua; Sha, Yi-Gao

    1995-01-01

    The studies on the crystal growth and characterization of II-VI wide band gap compound semiconductors, such as ZnTe, CdS, ZnSe and ZnS, have been conducted over the past three decades. The research was not quite as extensive as that on Si, III-V, or even narrow band gap II-VI semiconductors because of the high melting temperatures as well as the specialized applications associated with these wide band gap semiconductors. In the past several years, major advances in the thin film technology such as Molecular Beam Epitaxy (MBE) and Metal Organic Chemical Vapor Deposition (MOCVD) have demonstrated the applications of these materials for the important devices such as light-emitting diode, laser and ultraviolet detectors and the tunability of energy band gap by employing ternary or even quaternary systems of these compounds. At the same time, the development in the crystal growth of bulk materials has not advanced far enough to provide low price, high quality substrates needed for the thin film growth technology.

  1. Bulk Growth of Wide Band Gap II-VI Compound Semiconductors by Physical Vapor Transport

    Science.gov (United States)

    Su, Ching-Hua

    1997-01-01

    The mechanism of physical vapor transport of II-VI semiconducting compounds was studied both theoretically, using a one-dimensional diffusion model, as well as experimentally. It was found that the vapor phase stoichiometry is critical in determining the vapor transport rate. The experimental heat treatment methods to control the vapor composition over the starting materials were investigated and the effectiveness of the heat treatments was confirmed by partial pressure measurements using an optical absorption technique. The effect of residual (foreign) gas on the transport rate was also studies theoretically by the diffusion model and confirmed experimentally by the measurements of total pressure and compositions of the residual gas. An in-situ dynamic technique for the transport rate measurements and a further extension of the technique that simultaneously measured the partial pressures and transport rates were performed and, for the first time, the experimentally determined mass fluxes were compared with those calculated, without any adjustable parameters, from the diffusion model. Using the information obtained from the experimental transport rate measurements as guideline high quality bulk crystal of wide band gap II-VI semiconductor were grown from the source materials which undergone the same heat treatment methods. The grown crystals were then extensively characterized with emphasis on the analysis of the crystalline structural defects.

  2. Emission Channeling Investigation of Implantation Defects and Impurities in II-VI-Semiconductors

    CERN Multimedia

    Trojahn, I; Malamud, G; Straver, J; Ronnqvist, C; Jahn, S-G; Restle, M

    2002-01-01

    Detailed knowledge on the behaviour of implantation damage and its influence on the lattice position and environment of implanted dopants in II-VI-compound semiconductors is necessary for a clear interpretation of results from other investigation methods and finally for technical utilization. Besides, a precise localization of impurities could help to clarify the discussion about the instability of the electrical properties of some dopants, called " aging ".\\\\ \\\\We intend to use the emission channeling method to investigate: \\\\ \\\\i) The behaviour of implantation damage which shall be probed by the lattice location of isoelectronic isotopes (Zn,Cd,Hg,Se,Te) directly after implantation at different temperatures, doses and vacancy densities and after annealing treatments, and ii) the precise lattice sites of the acceptor Ag and donor In under different conditions by implanting precursors Cd and In isotopes. \\\\ \\\\Further on we would like to test the application of a two-dimensional position and energy sensitive e...

  3. Reduction of U(VI) by Fe(II) in the presence of hydrous ferric oxide and hematite: effects of solid transformation, surface coverage, and humic acid.

    Science.gov (United States)

    Jang, Je-Hun; Dempsey, Brian A; Burgos, William D

    2008-04-01

    Fe(II) was added to U(VI)-spiked suspensions of hydrous ferric oxide (HFO) or hematite to compare the redox behaviors of uranium in the presence of two different Fe(III) (oxyhydr)oxides. Experiments were conducted with low or high initial sorption density of U(VI) and in the presence or absence of humic acid (HA). About 80% of U(VI) was reduced within 3 days for low sorbed U(VI) conditions, with either hematite or HFO. The {Fe(3+)} in the low U(VI) experiments at 3 days, based on measured Fe(II) and U(VI) and the assumed presence of amorphous UO(2(s)), was consistent with control by HFO for either initial Fe(III) (oxyhydr)oxide. After about 1 day, partial re-oxidation to U(VI) was observed in the low sorbed U(VI) experiments in the absence of HA, without equivalent increase of dissolved U(VI). No reduction of U(VI) was observed in the high sorbed U(VI) experiments; it was hypothesized that the reduction required sorption proximity of U(VI) and Fe(II). Addition of 5mg/L HA slowed the reduction with HFO and had less effect with hematite. Mössbauer spectroscopy (MBS) of (57)Fe(II)-enriched samples identified the formation of goethite, hematite, and non-stoichiometric magnetite from HFO, and the formation of HFO, hydrated hematite, and non-stoichiometric magnetite from hematite.

  4. Mechanistic insight into chromium(VI) reduction by oxalic acid in the presence of manganese(II)

    Energy Technology Data Exchange (ETDEWEB)

    Wrobel, Katarzyna; Corrales Escobosa, Alma Rosa; Gonzalez Ibarra, Alan Alexander; Mendez Garcia, Manuel; Yanez Barrientos, Eunice; Wrobel, Kazimierz, E-mail: kazimier@ugto.mx

    2015-12-30

    Over the past few decades, reduction of hexavalent chromium (Cr(VI)) has been studied in many physicochemical contexts. In this research, we reveal the mechanism underlying the favorable effect of Mn(II) observed during Cr(VI) reduction by oxalic acid using liquid chromatography with spectrophotometric diode array detector (HPLC–DAD), nitrogen microwave plasma atomic emission spectrometry (HPLC–MP-AES), and high resolution mass spectrometry (ESI–QTOFMS). Both reaction mixtures contained potassium dichromate (0.67 mM Cr(VI)) and oxalic acid (13.3 mM), pH 3, one reaction mixture contained manganese sulfate (0.33 mM Mn(II)). In the absence of Mn(II) only trace amounts of reaction intermediates were generated, most likely in the following pathways: (1) Cr(VI) → Cr(IV) and (2) Cr(VI) + Cr(IV) → 2Cr(V). In the presence of Mn(II), the active reducing species appeared to be Mn(II) bis-oxalato complex (J); the proposed reaction mechanism involves a one-electron transfer from J to any chromium compound containing Cr=O bond, which is reduced to Cr−OH, and the generation of Mn(III) bis-oxalato complex (K). Conversion of K to J was observed, confirming the catalytic role of Mn(II). Since no additional acidification was required, the results obtained in this study may be helpful in designing a new, environmentally friendly strategy for the remediation of environments contaminated with Cr(VI).

  5. Enhancement strategies for Cu(II), Cr(III) and Cr(VI) remediation by a variety of seaweed species.

    Science.gov (United States)

    Murphy, V; Hughes, H; McLoughlin, P

    2009-07-15

    Various chemical treatments have been applied to six brown, red and green seaweed species with a view to enhancing their metal removal for Cu(II), Cr(III) and Cr(VI). Treatment with acetone resulted in the greatest enhancement for both cationic and anionic species with relatively low mass losses (15-35%), indicating its low risk to biomass operational stability. Cation binding was increased by 69%, while the total Cr removal was augmented by 15%. Cr(VI) binding was shown to be an adsorption-coupled reduction, whereby Cr(VI) was bound to the biomass surface at pH 2 and subsequently reduced to Cr(III). Acetone treatment also resulted in biomasses that were capable of converting up to 83% of Cr(VI) in solution to Cr(III). Blocking of carboxyl and amino functionalities had significant negative effects both on total Cr removal as well as percentage conversion of Cr(VI) to Cr(III). Results therefore indicated the significant role played by these moieties in metal binding to these seaweeds. Potentiometric titrations displayed agreement between the degree of esterification and the decrease in Cu(II) removal for Ulva spp. and Polysiphonia lanosa. FTIR analysis identified changes in biomass functionality and availability after chemical modification, the results of which were in agreement with metal removal studies. In conclusion, these biosorbents represent suitable candidates to replace conventional removal technologies for metal bearing wastewaters, in particular for the detoxification of hazardous Cr(VI) waste streams.

  6. Conserved water-mediated hydrogen bond network between TM-I, -II, -VI, and -VII in 7TM receptor activation

    DEFF Research Database (Denmark)

    Nygaard, Rie; Hansen, Louise Valentin; Mokrosinski, Jacek

    2010-01-01

    Five highly conserved polar residues connected by a number of structural water molecules together with two rotamer micro-switches, TrpVI:13 and TyrVII:20, constitute an extended hydrogen bond network between the intracellular segments of TM-I, -II, -VI, and -VII of 7TM receptors. Molecular dynamics...... simulations showed that, although the fewer water molecules in rhodopsin were relatively movable, the hydrogen bond network of the beta2-adrenergic receptor was fully loaded with water molecules that were surprisingly immobilized between the two rotamer switches, both apparently being in their closed...... conformation. Manipulations of the rotamer state of TyrVII:20 and TrpVI:13 demonstrated that these residues served as gates for the water molecules at the intracellular and extracellular ends of the hydrogen bond network, respectively. TrpVI:13 at the bottom of the main ligand-binding pocket was shown...

  7. Recent Progress in Photocatalysis Mediated by Colloidal II-VI Nanocrystals

    Science.gov (United States)

    Wilker, Molly B; Schnitzenbaumer, Kyle J; Dukovic, Gordana

    2012-01-01

    The use of photoexcited electrons and holes in semiconductor nanocrystals as reduction and oxidation reagents is an intriguing way of harvesting photon energy to drive chemical reactions. This review focuses on recent research efforts to understand and control the photocatalytic processes mediated by colloidal II-VI nanocrystalline materials, such as cadmium and zinc chalcogenides. First, we highlight how nanocrystal properties govern the rates and efficiencies of charge-transfer processes relevant to photocatalysis. We then describe the use of nanocrystal catalyst heterostructures for fuel-forming reactions, most commonly H2 generation. Finally, we review the use of nanocrystal photocatalysis as a synthetic tool for metal–semiconductor nano-heterostructures. PMID:24115781

  8. Optical studies of charged excitons in II-VI semiconductor quantum wells

    CERN Document Server

    Kossacki, P

    2003-01-01

    A brief review is given of optical studies of doped II-VI quantum wells. The properties of exciton states, neutral as well as positively and negatively charged, are discussed. A wide range of optical measurements is presented: CW as well as picosecond and femtosecond time-resolved absorption, photoluminescence (PL) and PL excitation. The experiments were performed at various carrier concentrations (> 10 sup 1 sup 1 cm sup - sup 2) and temperatures (up to a few tens of kelvins). This review is limited to zero or low magnetic fields, used only to polarize spins of carriers. We discuss the obtained values of various fundamental parameters of the excitonic states: energies, optical transition probabilities and characteristic times of their formation, thermalization and decay. (topical review)

  9. Combined Electrical, Optical and Nuclear Investigations of Impurities and Defects in II-VI Semiconductors

    CERN Multimedia

    2002-01-01

    % IS325 \\\\ \\\\ To achieve well controlled bipolar conductivity in II-VI semiconductors represents a fundamental problem in semiconductor physics. The doping problems are controversely discussed, either in terms of self compensation or of compensation and passivation by unintentionally introduced impurities. \\\\ \\\\It is the goal of our experiments at the new ISOLDE facility, to shed new light on these problems and to look for ways to circumvent it. For this aim the investigation of impurities and native defects and the interaction between each other shall be investigated. The use of radioactive ion beams opens the access to controlled site selective doping of only one sublattice via nuclear transmutation. The compensating and passivating mechanisms will be studied by combining nuclear, electrical and optical methods like Perturbed Angular Correlation~(PAC), Hall Effect~(HE), Deep Level Transient Spectroscopy~(DLTS), Photoluminescence Spectroscopy~(PL) and electron paramagnetic resonance (EPR). \\\\ \\\\We intend to ...

  10. Natural Intermediate Band in I 2 -II-IV-VI4 Quaternary Chalcogenide Semiconductors.

    Science.gov (United States)

    Liu, Qiheng; Cai, Zenghua; Han, Dan; Chen, Shiyou

    2018-01-25

    An intermediate band in the band gap of semiconductors is fundamental to the development of the intermediate band solar cells, but it is usually produced artificially, which imposes technical challenges on the experimental realization. Here we found that there are natural intermediate bands in the band gaps of the I2-II-IV-VI4 quaternary chalcogenide semiconductors such as Cu2ZnSnS4 and Ag2ZnSnSe4, which had been proposed as promising light-absorber semiconductors in thin film solar cells. By first-principles calculations, we found the lowest conduction band of these I2-II-IV-VI4 semiconductors in the kesterite structure is isolated (a lone band, resulting from the energy separation between Sn 5s and 5p states), which can be viewed as a natural intermediate band. The gap between the intermediate band and higher-energy conduction band can be increased through changing the crystal structure from the zincblende-derived kesterite structure to the wurtzite-derived wurtzite-kesterite structure. In contrast, the intermediate-conduction band gap shrinks when the component element Sn is replaced by Ge (Cu2ZnGeS4), and the gap even disappears (intermediate band disappear) when Sn is replaced by Si (Cu2ZnSiS4). Through tuning the intermediate-conduction and intermediate-valence band gaps, we show that the wurtzite-kesterite structured Ag2ZnSnSe4 may be a potential light-absorber semiconductor in intermediate band solar cells.

  11. Single and combined removal of Cr(VI) and Cd(II) by nanoscale zero-valent iron in the absence and presence of EDDS.

    Science.gov (United States)

    Dong, Haoran; Zeng, Yalan; Xie, Yankai; He, Qi; Zhao, Feng; Wang, Yang; Zeng, Guangming

    2017-09-01

    This study examined the feasibility of nanoscale zero-valent iron (nZVI) for the single and combined removal of Cr(VI) and Cd(II) with or without ethylene diamine disuccinic acid (EDDS). The effects of pH and dissolved oxygen (DO) on the removal process were investigated. Results show that the single removal of either Cr(VI) or Cd(II) by nZVI was pH dependent, where the higher Cr(VI) removal was achieved under acidic conditions, whereas the higher Cd(II) removal was achieved under alkaline conditions. The presence of DO enhanced Cd(II) removal but inhibited Cr(VI) removal under alkaline conditions. In the co-existence of Cr(VI) and Cd(II), it was found that Cd(II) exerted insignificant effect on Cr(VI) removal, while the presence of Cr(VI) remarkably enhanced the Cd(II) removal. The addition of EDDS exhibited different influences on Cr(VI) and Cd(II) removal, which were associated with pH and DO. The EDDS enhanced Cr(VI) removal at pH 5.6-9.0 in the absence of DO, but decreased Cr(VI) removal at pH 9.0 in the presence of DO. For the removal of Cd(II) at pH 5.6-7.0, either facilitation or inhibition effect of EDDS was observed, depending on EDDS concentration and the co-existence of Cr(VI). However, Cd(II) removal was always significantly inhibited by EDDS at pH 9.0.

  12. Determination of Pb(II), Zn(II), Cd(II), and Co(II) ions by flame atomic absorption spectrometry in food and water samples after preconcentration by coprecipitation with Mo(VI)-diethyldithiocarbamate.

    Science.gov (United States)

    Tufekci, Mehmet; Bulut, Volkan Numan; Elvan, Hamide; Ozdes, Duygu; Soylak, Mustafa; Duran, Celal

    2013-02-01

    A new, simple, and rapid separation and preconcentration procedure, for determination of Pb(II), Cd(II), Zn(II), and Co(II) ions in environmental real samples, has been developed. The method is based on the combination of coprecipitation of analyte ions by the aid of the Mo(VI)-diethyldithiocarbamate-(Mo(VI)-DDTC) precipitate and flame atomic absorption spectrometric determinations. The effects of experimental conditions like pH of the aqueous solution, amounts of DDTC and Mo(VI), standing time, centrifugation rate and time, sample volume, etc. and also the influences of some foreign ions were investigated in detail on the quantitative recoveries of the analyte ions. The preconcentration factors were found to be 150 for Pb(II), Zn(II) and Co(II), and 200 for Cd(II) ions. The detection limits were in the range of 0.1-2.2 μg L(-1) while the relative standard deviations were found to be lower than 5 % for the studied analyte ions. The accuracy of the method was checked by spiked/recovery tests and the analysis of certified reference material (CRM TMDW-500 Drinking Water). The procedure was successfully applied to seawater and stream water as liquid samples and baby food and dried eggplant as solid samples in order to determine the levels of Pb(II), Cd(II), Zn(II), and Co(II) ions.

  13. Influence of Arsenic (III, Cadmium (II, Chromium (VI, Mercury (II, and Lead (II Ions on Human Triple Negative Breast Cancer (HCC1806 Cell Cytotoxicity and Cell Viability

    Directory of Open Access Journals (Sweden)

    Tsdale F. Mehari

    2017-01-01

    Full Text Available The hazardous consequences of heavy metal ions (HMIs on human health necessitate the immediate need to probe fundamentally the interactions and cytotoxic effects of HMIs on humans. This study investigated the influence of five toxic HMIs (arsenic (As (III, cadmium (Cd (II, chromium (Cr (VI, mercury (Hg (II, and lead (Pb (II on human TNBC (HCC 1806 cell viability using optical microscopy, trypan blue dye-exclusion assays, and flow cytometry. The TNBC cells were exposed to varying concentrations of HMIs for 24 and 48 hours. We evaluated the influence of the concentrations and duration of HMIs exposure on TNBC cell viability. Light microscopy, cell viability assays, revealed that after 48-hour treatment of TNBC cells with 1 x 10-5 M of As (III, Cd (II, Hg (II, Cr (IV, and Pb (II resulted in cell viabilities of 23%, 34%, 35%, 56%, 91% respectively, suggesting that As (III has the greatest cytotoxicity (77% cell death while Pb (II showed the least (9% cell death. Furthermore, flow cytometry revealed that while Pb (II, As (III and Cr (IV had significant increases in cell death, Hg (II caused a G1 arrest. Together, this study revealed that HMIs cause a differential cytotoxic effect on TNBC cells and suggest that they may have very different genotoxic targets and implications in their mutagenic potential.

  14. Optical properties of II-VI semiconductor nanoclusters for use as phosphors

    Science.gov (United States)

    Wilcoxon, Jess P.; Newcomer, Paula

    2002-11-01

    The optical properties of both II-VI (direct gap) and type IV (indirect gap) nanosize semiconductors are significantly affected not only by their size, but by the nature of the chemical interface of the cluster with the embedding medium. This affects the light conversion efficiency and can alter the shape and position (i.e. the color) of the photoluminescence (PL). As the goal of our work is to embed nanoclusters into either organic or inorganic matrices for use as near UV, LED-excited phosphor thin films, understanding and controlling this interface is very important for preserving the high Q.E. of nanoclusters known for dilute solution conditions. We describe a room temperature synthesis of semiconductor nanoclusters which employs inexpensive, less toxic ionic precursors (metal salts), and simple coordinating solvents (e.g. tetrahydrofuran). This allows us to add passivating agents, ions, metal or semiconductor coatings to identical, highly dispersed bare clusters, post-synthesis. We can also increase the cluster size by heterogeneous growth on the seed nanoclusters. One of the most interesting observations for our II-VI nanomaterials is that both the absorbance excitonic features and the photoluminescence (PL) energy and intensity depend on the nature of the surface as well as the average size. In CdS, for example, the presence of electron traps (i.e Cd(II) sites) decreases the exciton absorbance peak amplitude but increases the PL nearly two-fold. Hole traps (i.e. S(II)) have the opposite effect. In the coordinating solvents used for the synthesis, the PL yield for d~2 nm, blue emitting CdSe clusters increases dramatically with sample age as the multiple absorbance features sharpen. Liquid chromatographic (LC) separation of the nanoclusters from other chemicals and different sized clusters is used to investigate the intrinsic optical properties of the purified clusters and identify which clusters are contributing most strongly to the PL. Both LC and dynamic

  15. Single, simultaneous and consecutive biosorption of Cr(VI) and Orange II onto chemically modified masau stones.

    Science.gov (United States)

    Albadarin, Ahmad B; Solomon, Samuel; Kurniawan, Tonni Agustiono; Mangwandi, Chirangano; Walker, Gavin

    2017-12-15

    Novel and low cost chemically modified masau stone (CMMS) was investigated for its biosorption of an anionic azo dye, Orange II (OII), and toxic hexavalent chromium (Cr(VI)) from aqueous systems: individually, simultaneously and consecutively. XPS and FTIR analyses indicated the introduction of quaternary-Nitrogen to the CMMS surface after activation with epichlorohydrin (etherifying agent) and diethylenetriamine (crosslinking agent). The effects of pH, contact time and initial concentration (Co), and loading order on mechanisms of biosorption/reduction of OII and Cr(VI) onto CMMS were examined in detail. Several analytical techniques were employed to characterise the physio-chemical properties of the CMMS and determine the biosorption mechanisms. The pseudo second order and redox models were able to adequately predict the kinetics of biosorption. The Langmuir maximum OII biosorption capacity (qmax) was calculated as 136.8 mg/g for the dye onto the Cr(VI)-loaded CMMS consecutive system at Co = 100 mg/dm3. The qmax for the Cr(VI) system was found to be 87.32 mg/g at the same Co max. This reveals that the biosorption of OII and Cr(VI) mainly takes place via two different mechanisms i.e. hydrogen bonding and electrostatic attraction for the dye, and biosorption-coupled reduction for Cr(VI). Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. All-vapor processing of P-type tellurium-containing II-VI semiconductor and ohmic contacts thereof

    Energy Technology Data Exchange (ETDEWEB)

    McCandless, Brian E.

    2000-03-01

    An all dry method for producing solar cells is provided comprising first heat-annealing a II-VI semiconductor; enhancing the conductivity and grain size of the annealed layer; modifying the surface and depositing a tellurium layer onto the enhanced layer; and then depositing copper onto the tellurium layer so as to produce a copper tellurium compound on the layer.

  17. Manipulation of spin states in single II-VI-semiconductor quantum dots; Manipulation von Spinzustaenden in einzelnen II-VI-Halbleiter-Quantenpunkten

    Energy Technology Data Exchange (ETDEWEB)

    Hundt, Andreas

    2007-10-09

    Semiconductor quantum dots (QD) are objects on the nanometer scale, where charge carriers are confined in all three dimensions. This leads to a reduced interaction with the semiconductor lattice and to a discrete density of states. The spin state of a particle defines the polarisation of the emitted light when relaxating to an energetically lower state. Spin exchange and optical transition selection rules (conservation law for spin) define the optical control of spin states. In the examined QD in II-VI seminconductor systems the large polar character of the bindings enables to observe particle interactions by spectroscopy of the photo-luminescence (PL), making QD attractive for basic research. This work subjects in its first part single negatively charged non-magnetic QD. The odd number of carriers allows to study the latter in an unpaired state. By using polarization-resolved micro-PL spectroscopy, the spin-states of single, isolated QD can be studied reproducibly. Of special interest are exchange interactions in this few-particle system named trion. By excitation spectroscopy energetically higher states can be identified and characterized. The exchange interactions appearing here lead to state mixing and fine structure patterns in the spectra. Couplings in excited hole states show the way to the optical orientation of the resident electron spin. The spin configuration of the trion triplet state can be used to optically control the resident electron spin. Semimagnetic QD are focused in the second part of this work. The interaction with a paramagnetic environment of manganese spins leads to new magneto-optical properties of the QD. They reveal on a single dot level by line broadening due to spin fluctuations and by the giant Zeeman effect of the dot ensemble. Of special interest in this context is the influence of the reduced system dimension and the relatively larger surface of the system on the exchange mechanisms. The strong temperature dependence of the spin

  18. Karakterisasi Adsorben dari Kulit Manggis dan Kinerjanya pada Adsorpsi Logam Pb(II dan Cr(VI - (Adsorbent Characterization from Mangosteen Peel and Its Adsorption Performance on Pb(II and Cr(VI

    Directory of Open Access Journals (Sweden)

    Ulfa Haura

    2017-06-01

    Full Text Available The usage of biomass waste-based adsorbent for the adsorption of hazardous metal in wastewater is not only reducing waste but also lowering adsorbent price. This research aims to study the characteristics of adsorbent from mangosteen peel (Garcinia Mangostana L. and activated charcoal from mangosteen peel, also to compare the adsorption performance on metal ion Pb(II and Cr(VI. Synthetic wastewater used from a solution of Pb(NO32 and K2Cr2O7 with variations in initial concentration of 20, 40, 80, 100 and 200 mg/L. Adsorption performed at pH 5, ratio of adsorbent and waste solution 1/200 (w/v, 60 rpm, 0.5 gs nano-sized adsorbent. Characterization using SEM, FTIR and SEM-EDS showed that both adsorbents characteristics met the requirements of SNI 06-3730-1995. The highest adsorption capacity of activated carbon to adsorb Pb(II and Cr(VI were 38.543 mg/g and 36.838 mg/g while biosorbent adsorb Pb(II and Cr(VI respectively 3.98 mg/g and 36.12 mg/g.Keywords: adsorption, biosorbent, Cr(VI, mangosteen peel, Pb(IIABSTRAKPenggunaan adsorben berbasis limbah biomassa untuk adsorpsi kandungan logam berbahaya dari limbah cair industri selain dapat mengurangi limbah juga dapat menekan harga jual adsorben. Penelitian ini bertujuan untuk mempelajari karakteristik adsorben yang terbuat dari limbah kulit manggis (Garcinia mangostana L. dan arang aktif dari limbah kulit manggis serta membandingkan kinerja kedua jenis adsorben tersebut pada proses adsorpsi ion logam Pb(II dan Cr(VI. Limbah sintetis yang digunakan berupa ion dari Pb(II dan Cr(VI dari larutan Pb(NO32 dan K2Cr2O7 dengan variasi konsentrasi awal 20, 40, 80, 100 dan 200 mg/L. Proses adsorpsi dilakukan pada pH 5, rasio perbandingan berat adsorben dan volume larutan limbah 1:200, kecepatan pengadukan 60 rpm, adsorben berukuran nano dengan berat adsorben 0,5 g. Masing-masing adsorben dikarakterisasi menggunakan SEM untuk mengetahui sturktur morfologi, FTIR untuk mengetahui gugus fungsi dan SEM-EDS untuk

  19. Catalytic role of Cu(II) in the reduction of Cr(VI) by citric acid under an irradiation of simulated solar light.

    Science.gov (United States)

    Li, Ying; Chen, Cheng; Zhang, Jing; Lan, Yeqing

    2015-05-01

    The catalytic role of Cu(II) in the reduction of Cr(VI) by citric acid with simulated solar light was investigated. The results demonstrated that Cu(II) could significantly accelerate Cr(VI) reduction and the reaction obeyed to pseudo zero-order kinetics with respect to Cr(VI). The removal of Cr(VI) was related to the initial concentrations of Cu(II), citric acid, and the types of organic acids. The optimal removal of Cr(VI) was achieved at pH 4, and the rates of Cu(II) photocatalytic reduction of Cr(VI) by organic acids were in the order: tartaric acid (two α-OH groups, two -COOH groups)>citric acid (one α-OH group, three -COOH groups)>malic acid (one α-OH group, two -COOH groups)>lactic acid (one α-OH group, one -COOH group)≫succinic acid (two -COOH groups), suggesting that the number of α-OH was the key factor for the reaction, followed by the number of -COOH. The formation of Cu(II)-citric acid complex could generate Cu(I) and radicals through a pathway of metal-ligand-electron transfer, promoting the reduction of Cr(VI). This study is helpful to fully understanding the conversion of Cr(VI) in the existence of both organic acids and Cu(II) with solar light in aquatic environments. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Batatinosides II-VI, acylated lipooligosaccharides from the resin glycosides of sweet potato.

    Science.gov (United States)

    Escalante-Sánchez, Edgar; Rosas-Ramírez, Daniel; Linares, Edelmira; Bye, Robert; Pereda-Miranda, Rogelio

    2008-10-22

    Sweet potato ( Ipomoea batatas) belongs to the Convolvulaceae (morning glory family) and is native to Mexico and Central America. Its edible tuberous roots have been much appreciated since pre-Hispanic times in Mesoamerica and now play an important role as a basic diet staple and a medicinal plant worldwide. The hexane-soluble extract from roots, through preparative-scale recycling HPLC, yielded five new lipophilic oligosaccharides of jalapinolic acid, batatinosides II-VI ( 1- 5), as well as the known pescapreins I ( 6) and VII ( 7) and murucoidin I ( 8), which are part of the purgative resin glycoside mixture. NMR spectroscopy and FAB mass spectrometry were used to characterize their structures. Compounds 1 and 2 are tetraglycosidic lactones of operculinic acid C. The pentasaccharide structures for compounds 3 and 4 were confirmed to be macrolactones of simonic acid B, and that characterized for 5 was derived from operculinic acid A. The lactonization site of the aglycone was placed at C-3 of the second saccharide unit in all compounds except 4, where it was placed at C-2. All compounds contain an esterifying residue that is composed of a long-chain fatty acid, n-decanoic acid (capric) or n-dodecanoic acid (lauric). In compound 3, an additional short-chain fatty acid, (2 S)-methylbutyric acid, was also identified.

  1. Mucopolysaccharidosis I, II, and VI: brief review and guidelines for treatment

    Directory of Open Access Journals (Sweden)

    Roberto Giugliani

    2010-01-01

    Full Text Available Mucopolysaccharidoses (MPS are rare genetic diseases caused by the deficiency of one of the lysosomal enzymes involved in the glycosaminoglycan (GAG breakdown pathway. This metabolic block leads to the accumulation of GAG in various organs and tissues of the affected patients, resulting in a multisystemic clinical picture, sometimes including cognitive impairment. Until the beginning of the XXI century, treatment was mainly supportive. Bone marrow transplantation improved the natural course of the disease in some types of MPS, but the morbidity and mortality restricted its use to selected cases. The identification of the genes involved, the new molecular biology tools and the availability of animal models made it possible to develop specific enzyme replacement therapies (ERT for these diseases. At present, a great number of Brazilian medical centers from all regions of the country have experience with ERT for MPS I, II, and VI, acquired not only through patient treatment but also in clinical trials. Taking the three types of MPS together, over 200 patients have been treated with ERT in our country. This document summarizes the experience of the professionals involved, along with the data available in the international literature, bringing together and harmonizing the information available on the management of these severe and progressive diseases, thus disclosing new prospects for Brazilian patients affected by these conditions.

  2. Crystallization of II-VI semiconductor compounds forming long microcrystalline linear assemblies

    Directory of Open Access Journals (Sweden)

    Marcelino Becerril

    2013-04-01

    Full Text Available In this work we report the formation of long microcrystalline linear self-assemblies observed during the thin film growth of several II-VI compounds. Polycrystalline CdTe, CdS, CdCO3, and nanocrystalline CdTe:Al thin films were prepared on glass substrates by different deposition techniques. In order to observe these crystalline formations in the polycrystalline materials, the thin film growth was suspended before the grains reached to form a continuous layer. The chains of semiconductor crystals were observed among many isolated and randomly distributed grains. Since CdTe, CdTe:Al, CdS and CdCO3 are not ferroelectric and/or ferromagnetic materials, the relevant problem would be to explain what is the mechanism through which the grains are held together to form linear chains. It is well known that some nanocrystalline materials form rods and wires by means of electrostatic forces. This occurs in polar semiconductors, where it is assumed that the attraction forces between surface polar faces of the small crystals are the responsible for the chains formation. Since there are not too many mechanisms responsible for the attraction we assume that a dipolar interaction is the force that originates the formation of chain-like grain clusters. The study of this property can be useful for the understanding of nucleation processes in the growth of semiconductor thin films.

  3. Oral-facial-digital syndrome with mesoaxial polysyndactyly, common AV canal, hirschsprung disease and sacral dysgenesis: Probably a transitional type between II, VI, variant of type VI or a new type

    Directory of Open Access Journals (Sweden)

    Rabah M. Shawky

    2014-07-01

    Full Text Available We report a 4 month old male infant, the first in order of birth of healthy first cousin consanguineous parents who has many typical features of oral-facial-digital syndrome type VI (OFDS VI including hypertelorism, bilateral convergent squint, depressed nasal bridge, and wide upturned nares, low set posteriorly rotated ears, long philtrum, gum hyperplasia with notches of the alveolar borders, high arched palate, and hyperplastic oral frenula. He has mesoaxial and postaxial, polysyndactyly which is the specific feature of OFDS VI, however the cerebellum is normal on MRI brain. He has also some rare congenital anomalies including common atrioventricular canal, hirschsprung disease, and sacral dysgenesis. This patient may have a transitional type between II and VI, a variant of type VI or a new type.

  4. Performance of TcI/TcVI/TcII Chagas-Flow ATE-IgG2a for universal and genotype-specific serodiagnosis of Trypanosoma cruzi infection

    Science.gov (United States)

    Alessio, Glaucia Diniz; de Araújo, Fernanda Fortes; Côrtes, Denise Fonseca; Sales Júnior, Policarpo Ademar; Lima, Daniela Cristina; Gomes, Matheus de Souza; do Amaral, Laurence Rodrigues; Xavier, Marcelo Antônio Pascoal; Teixeira-Carvalho, Andréa; Martins-Filho, Olindo Assis; de Lana, Marta

    2017-01-01

    Distinct Trypanosoma cruzi genotypes have been considered relevant for patient management and therapeutic response of Chagas disease. However, typing strategies for genotype-specific serodiagnosis of Chagas disease are still unavailable and requires standardization for practical application. In this study, an innovative TcI/TcVI/TcII Chagas Flow ATE-IgG2a technique was developed with applicability for universal and genotype-specific diagnosis of T. cruzi infection. For this purpose, the reactivity of serum samples (percentage of positive fluorescent parasites-PPFP) obtained from mice chronically infected with TcI/Colombiana, TcVI/CL or TcII/Y strain as well as non-infected controls were determined using amastigote-AMA, trypomastigote-TRYPO and epimastigote-EPI in parallel batches of TcI, TcVI and TcII target antigens. Data demonstrated that “α-TcII-TRYPO/1:500, cut-off/PPFP = 20%” presented an excellent performance for universal diagnosis of T. cruzi infection (AUC = 1.0, Se and Sp = 100%). The combined set of attributes “α-TcI-TRYPO/1:4,000, cut-off/PPFP = 50%”, “α-TcII-AMA/1:1,000, cut-off/PPFP = 40%” and “α-TcVI-EPI/1:1,000, cut-off/PPFP = 45%” showed good performance to segregate infections with TcI/Colombiana, TcVI/CL or TcII/Y strain. Overall, hosts infected with TcI/Colombiana and TcII/Y strains displayed opposite patterns of reactivity with “α-TcI TRYPO” and “α-TcII AMA”. Hosts infected with TcVI/CL strain showed a typical interweaved distribution pattern. The method presented a good performance for genotype-specific diagnosis, with global accuracy of 69% when the population/prototype scenario include TcI, TcVI and TcII infections and 94% when comprise only TcI and TcII infections. This study also proposes a receiver operating reactivity panel, providing a feasible tool to classify serum samples from hosts infected with distinct T. cruzi genotypes, supporting the potential of this method for universal and genotype

  5. Interface control of electronic and optical properties in IV-VI and II-VI core/shell colloidal quantum dots: a review.

    Science.gov (United States)

    Jang, Youngjin; Shapiro, Arthur; Isarov, Maya; Rubin-Brusilovski, Anna; Safran, Aron; Budniak, Adam K; Horani, Faris; Dehnel, Joanna; Sashchiuk, Aldona; Lifshitz, Efrat

    2017-01-17

    Semiconductor colloidal quantum dots (CQDs) have attracted vast scientific and technological interest throughout the past three decades, due to the unique tuneability of their optoelectronic properties by variation of size and composition. However, the nanoscale size brings about a large surface-to-bulk volume ratio, where exterior surfaces have a pronounced influence on the chemical stability and on the physical properties of the semiconductor. Therefore, numerous approaches have been developed to gain efficient surface passivation, including a coverage by organic or inorganic molecular surfactants as well as the formation of core/shell heterostructures (a semiconductor core epitaxially covered by another semiconductor shell). This review focuses on special designs of core/shell heterostructures from the IV-VI and II-VI semiconductor compounds, and on synthetic approaches and characterization of the optical properties. Experimental observations revealed the formation of core/shell structures with type-I or quasi-type-II band alignment between the core and shell constituents. Theoretical calculations of the electronic band structures, which were also confirmed by experimental work, exposed surplus electronic tuning (beyond the radial diameter) with adaptation of the composition and control of the interface properties. The studies also considered strain effects that are created between two different semiconductors. It was disclosed experimentally and theoretically that the strain can be released via the formation of alloys at the core-shell interface. Overall, the core/shell and core/alloyed-shell heterostructures showed enhancement in luminescence quantum efficiency with respect to that of pure cores, extended lifetime, uniformity in size and in many cases good chemical sustainability under ambient conditions.

  6. Synthesis, Characterization and Biological Activities of Cu(II, Co(II, Mn(II, Fe(II, and UO2(VI Complexes with a New Schiff Base Hydrazone: O-Hydroxyacetophenone-7-chloro-4-quinoline Hydrazone

    Directory of Open Access Journals (Sweden)

    Nora H. Al-Shaalan

    2011-10-01

    Full Text Available The Schiff base hydrazone ligand HL was prepared by the condensation reaction of 7-chloro-4-quinoline with o-hydroxyacetophenone. The ligand behaves either as monobasic bidentate or dibasic tridentate and contain ONN coordination sites. This was accounted for be the presence in the ligand of a phenolic azomethine and imine groups. It reacts with Cu(II, Ni(II, Co(II, Mn(II, UO2 (VI and Fe(II to form either mono- or binuclear complexes. The ligand and its metal complexes were characterized by elemental analyses, IR, NMR, Mass, and UV-Visible spectra. The magnetic moments and electrical conductance of the complexes were also determined. The Co(II, Ni(II and UO2 (VI complexes are mononuclear and coordinated to NO sites of two ligand molecules. The Cu(II complex has a square-planar geometry distorted towards tetrahedral, the Ni(II complex is octahedral while the UO2 (VI complex has its favoured heptacoordination. The Co(II, Mn(II complexes and also other Ni(II and Fe(III complexes, which were obtained in the presence of Li(OH as deprotonating agent, are binuclear and coordinated via the NNNO sites of two ligand molecules. All the binuclear complexes have octahedral geometries and their magnetic moments are quite low compared to the calculated value for two metal ions complexes and thus antiferromagnetic interactions between the two adjacent metal ions. The ligand HL and metal complexes were tested against a strain of Gram +ve bacteria (Staphylococcus aureus, Gram −ve bacteria (Escherichia coli, and fungi (Candida albicans. The tested compounds exhibited high antibacterial activities.

  7. Conserved Water-mediated Hydrogen Bond Network between TM-I, -II, -VI, and -VII in 7TM Receptor Activation*

    Science.gov (United States)

    Nygaard, Rie; Valentin-Hansen, Louise; Mokrosinski, Jacek; Frimurer, Thomas M.; Schwartz, Thue W.

    2010-01-01

    Five highly conserved polar residues connected by a number of structural water molecules together with two rotamer micro-switches, TrpVI:13 and TyrVII:20, constitute an extended hydrogen bond network between the intracellular segments of TM-I, -II, -VI, and -VII of 7TM receptors. Molecular dynamics simulations showed that, although the fewer water molecules in rhodopsin were relatively movable, the hydrogen bond network of the β2-adrenergic receptor was fully loaded with water molecules that were surprisingly immobilized between the two rotamer switches, both apparently being in their closed conformation. Manipulations of the rotamer state of TyrVII:20 and TrpVI:13 demonstrated that these residues served as gates for the water molecules at the intracellular and extracellular ends of the hydrogen bond network, respectively. TrpVI:13 at the bottom of the main ligand-binding pocket was shown to apparently function as a catching trap for water molecules. Mutational analysis of the β2-adrenergic receptor demonstrated that the highly conserved polar residues of the hydrogen bond network were all important for receptor signaling but served different functions, some dampening constitutive activity (AsnI:18, AspII:10, and AsnVII:13), whereas others (AsnVII:12 and AsnVII:16) located one helical turn apart and sharing a water molecule were shown to be essential for agonist-induced signaling. It is concluded that the conserved water hydrogen bond network of 7TM receptors constitutes an extended allosteric interface between the transmembrane segments being of crucial importance for receptor signaling and that part of the function of the rotamer micro-switches, TyrVII:20 and TrpVI:13, is to gate or trap the water molecules. PMID:20395291

  8. Packed-bed column biosorption of chromium(VI) and nickel(II) onto Fenton modified Hydrilla verticillata dried biomass.

    Science.gov (United States)

    Mishra, Ashutosh; Tripathi, Brahma Dutt; Rai, Ashwani Kumar

    2016-10-01

    The present study represents the first attempt to investigate the biosorption potential of Fenton modified Hydrilla verticillata dried biomass (FMB) in removing chromium(VI) and nickel(II) ions from wastewater using up-flow packed-bed column reactor. Effects of different packed-bed column parameters such as bed height, flow rate, influent metal ion concentration and particle size were examined. The outcome of the column experiments illustrated that highest bed height (25cm); lowest flow rate (10mLmin(-1)), lowest influent metal concentration (5mgL(-1)) and smallest particle size range (0.25-0.50mm) are favourable for biosorption. The maximum biosorption capacity of FMB for chromium(VI) and nickel(II) removal were estimated to be 89.32 and 87.18mgg(-1) respectively. The breakthrough curves were analyzed using Bed Depth Service Time (BDST) and Thomas models. The experimental results obtained agree to both the models. Column regeneration experiments were also carried out using 0.1M HNO3. Results revealed good reusability of FMB during ten cycles of sorption and desorption. Performance of FMB-packed column in treating secondary effluent was also tested under identical experimental conditions. Results demonstrated significant reduction in chromium(VI) and nickel(II) ions concentration after the biosorption process. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Uranium(VI) reduction by nanoscale zero-valent iron in anoxic batch systems: The role of Fe(II) and Fe(III)

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Sen; Chen, Yongheng; Xiang, Wu; Bao, Zhengyu; Liu, Chongxuan; Deng, Baolin

    2014-12-01

    The role of Fe(II) and Fe(III) on U(VI) reduction by nanoscale zerovalent iron (nanoFe0) was investigated using two iron chelators 1,10-phenanthroline and triethanolamine (TEA) under a CO2-free anoxic condition. The results showed U(VI) reduction was strongly inhibited by 1,10-phenanthroline and TEA in a pH range from 6.92 to 9.03. For instance, at pH 6.92 the observed U(VI) reduction rates decreased by 80.7% and 82.3% in the presence of 1,10-phenanthroline and TEA, respectively. The inhibition was attributed to the formation of stable complexes between 1,10-phenanthroline and Fe(II) or TEA and Fe(III). In the absence of iron chelators, U(VI) reduction can be enhanced by surface-bound Fe(II) on nanoFe0. Our results suggested that Fe(III) and Fe(II) probably acted as an electron shuttle to mediate the transfer of electrons from nanoFe0 to U(VI), therefore a combined system with Fe(II), Fe(III) and nanoFe0 can facilitate the U(VI) reductive immobilization in the contaminated groundwater.

  10. Study on the Low Temperature Photoluminescence Spectra of II-VI Group Telluride Bulk Crystals.

    Science.gov (United States)

    Xu, Ya-dong; Liu, Hang; He, Yi-hui; Zhou, Yan; Jie, Wan-qi

    2015-03-01

    The dominant point defects in II-VI group telluride bulk crystals grown from melt usually varied due to different growth conditions and cooling history, in turn affect the electrical and optical behaviors of corresponding single crystals and devices. Low temperature photoluminescence (PL) spectra acts as a contact-less and non-destructive technique, can be used to evaluate the behaviors of point defects and impurities in the as-grown telluride bulk crystals. With the purpose of comparing the defect structures in un-doped ZnTe and CdTe crystals grown under Te-rich condition, 8. 6 K PL spectra were obtained. The conductivity type and resistivity were investigated by Hall-effect measurements at room temperature (RT). For p-type low resistivity ZnTe crystal, the intensity of. free electron to neutral acceptor (e, A(0)) transition is higher than the donor-acceptor pair (DAP) transition, which predominates in the PL spectra. However, in the contrary, DAP peak dominates the PL emissions for n-type high resistivity CdTe. This difference is mainly attributed to the distinct properties of the grown-in point defects due to different growth. velocities and cooling processes. In terms of the un-doped CdZnTe crystal grown under stoichiometry, neutral donor bound exciton (D(0), X) emission is predominated in the 9.2 K PL spectra, with the intensity of (e, A(0)) peak is higher than DAP peak, which then overlaps to each other when the temperature higher then 15 K. In the case of In-doped CdZnTe crystal grown by Te-rich situation, A-center emission is clearly observed, which introduces an energy level approximately of 0.15 eV, with the intensity proportional to the concentration of indium dopant. This defect is seemingly related to the complex of [In(Cd)+V(Cd)2-]- formed by a shallow donor In(Cd) and Cd vacancy.

  11. "Weathering" HOPE VI: the importance of evaluating the population health impact of public housing demolition and displacement.

    Science.gov (United States)

    Keene, Danya E; Geronimus, Arline T

    2011-06-01

    HOPE VI has funded the demolition of public housing developments across the United States and created in their place mixed-income communities that are often inaccessible to the majority of former tenants. This recent uprooting of low-income, urban, and predominantly African American communities raises concern about the health impacts of the HOPE VI program for a population that already shoulders an enormous burden of excess morbidity and mortality. In this paper, we rely on existing literature about HOPE VI relocation to evaluate the program from the perspective of weathering-a biosocial process hypothesized by Geronimus to underlie early health deterioration and excess mortality observed among African Americans. Relying on the weathering framework, we consider the effects of HOPE VI relocation on the material context of urban poverty, autonomous institutions that are health protective, and on the broader discourse surrounding urban poverty. We conclude that relocated HOPE VI residents have experienced few improvements to the living conditions and economic realities that are likely sources of stress and illness among this population. Additionally, we find that relocated residents must contend with these material realities, without the health-protective, community-based social resources that they often rely on in public housing. Finally, we conclude that by disregarding the significance of health-protective autonomous institutions and by obscuring the structural context that gave rise to racially segregated public housing projects, the discourse surrounding HOPE VI is likely to reinforce health-demoting stereotypes of low-income urban African American communities. Given the potential for urban and housing policies to negatively affect the health of an already vulnerable population, we argue that a health-equity perspective is a critical component of future policy conversations.

  12. Efeito da toxicidade de Cr (VI e Zn (II no crescimento do fungo filamentoso Aspergillus niger isolado de efluente industrial Toxicity effect of Cr (VI and Zn (II on growth of filamentous fungi Aspergillus niger isolated from industrial effluent

    Directory of Open Access Journals (Sweden)

    Maria do Socorro Vale

    2011-09-01

    Full Text Available Processos convencionais de tratamento de efluentes utilizam microrganismos vivos, o que sugere limitações relativas À toxicidade de metais para os microrganismos. O experimento consistiu em adicionar soluções monoelementares de Cr (VI e Zn(II em diferentes concentrações (0, 20, 50, 100, 200, 300, 400, 500 mg.L-1 ao meio de crescimento e observar a influência dos metais no crescimento micelial e germinativo do fungo Aspergillus Níger por verificação visual da expansão radial do micélio e da germinação de esporos, seguida de registro fotográfico. Os resultados mostraram que o metabolismo do fungo foi completamente inibido em concentrações acima de 500 mg Zn (II.L-1 e 150 mg Cr (VI.L-1. O ED50 (concentração de ingrediente ativo capaz de inibir 50% do crescimento micelial do fungo para os dois íons metálicos, nas condições estudadas, está na faixa entre 100 e 150 mg.L-1. Palavras-chave: metais pesados; inibição; crescimento micelial; Aspergillus niger; ED50.Many standard processes of wastewater treatment use live microorganisms, which suggests limitations on a metal toxicity to the microorganism. The experiment consisted in adding mono elementary solutions of Cr (VI and Zn (II at different concentrations (0, 20, 50, 100, 200, 300, 400, 500 mg.L-1 to the growth mean, and to observe the influence of metals on mycelial and germinative growth of the Aspergillus niger fungus, by means of visual observation of the radial expansion of the mycelius and the germination of spores, followed by photograph registration. The results showed that the metabolism of the fungus was completely inhibited at concentrations above 500 mg Zn (II.L-1 and 150 mg Cr (VI.L-1. The ED50 (concentration of active ingredient capable of inhibiting 50% of mycelial growth of the fungus for both metal ions, under the studied conditions, is in the range between 100 and 150 mg.L-1.

  13. The type VI secretion system impacts bacterial invasion and population dynamics in a model intestinal microbiota

    Science.gov (United States)

    Logan, Savannah L.; Shields, Drew S.; Hammer, Brian K.; Xavier, Joao B.; Parthasarathy, Raghuveer

    Animal gastrointestinal tracts are home to a diverse community of microbes. The mechanisms by which microbial species interact and compete in this dense, physically dynamic space are poorly understood, limiting our understanding of how natural communities are assembled and how different communities could be engineered. Here, we focus on a physical mechanism for competition: the type VI secretion system (T6SS). The T6SS is a syringe-like organelle used by certain bacteria to translocate effector proteins across the cell membranes of target bacterial cells, killing them. Here, we use T6SS+ and T6SS- strains of V. cholerae, the pathogen that causes cholera in humans, and light sheet fluorescence microscopy for in vivo imaging to show that the T6SS provides an advantage to strains colonizing the larval zebrafish gut. Furthermore, we show that T6SS+ bacteria can invade and alter an existing population of a different species in the zebrafish gut, reducing its abundance and changing the form of its population dynamics. This work both demonstrates a mechanism for altering the gut microbiota with an invasive species and explores the processes controlling the stability and dynamics of the gut ecosystem. Research Corporation, Gordon and Betty Moore Foundation, and the Simons Foundation.

  14. Carbonic Anhydrase I, II, and VI, Blood Plasma, Erythrocyte and Saliva Zinc and Copper Increase After Repetitive Transcranial Magnetic Stimulation

    Science.gov (United States)

    Henkin, Robert I.; Potolicchio, Samuel J.; Levy, Lucien M.; Moharram, Ramy; Velicu, Irina; Martin, Brian M.

    2010-01-01

    Introduction Repetitive transcranial magnetic stimulation (rTMS) has been used to treat symptoms from many disorders; biochemical changes occurred with this treatment. Preliminary studies with rTMS in patients with taste and smell dysfunction improved sensory function and increased salivary carbonic anhydrase (CA) VI and erythrocyte CA I, II. To obtain more information about these changes after rTMS, we measured changes in several CA enzymes, proteins, and trace metals in their blood plasma, erythrocytes, and saliva. Methods Ninety-three patients with taste and smell dysfunction were studied before and after rTMS in an open clinical trial. Before and after rTMS, we measured erythrocyte CA I, II and salivary CA VI, zinc and copper in parotid saliva, blood plasma, and erythrocytes, and appearance of novel salivary proteins by using mass spectrometry. Results After rTMS, CA I, II and CA VI activity and zinc and copper in saliva, plasma, and erythrocytes increased with significant sensory benefit. Novel salivary proteins were induced at an m/z value of 21.5K with a repetitive pattern at intervals of 5K m/z. Conclusions rTMS induced biochemical changes in specific enzymatic activities, trace metal concentrations, and induction of novel salivary proteins, with sensory improvement in patients with taste and smell dysfunction. Because patients with several neurologic disorders exhibit taste and smell dysfunction, including Parkinson disease, Alzheimer disease, and multiple sclerosis, and because rTMS improved their clinical symptoms, the biochemical changes we observed may be relevant not only in our patients with taste and smell dysfunction but also in patients with neurologic disorders with these sensory abnormalities. PMID:20090508

  15. Cyclopentadienyl molybdenum(II/VI) N-heterocyclic carbene complexes: Synthesis, structure, and reactivity under oxidative conditions

    KAUST Repository

    Li, Shenyu

    2010-04-26

    A series of N-heterocyclic carbene (NHC) complexes CpMo(CO) 2(NHC)X (NHC = IMe = 1,3-dimethylimidazol-2-ylidene, X = Br, 1; NHC = 1,3-dipropylimidazol-2-ylidene, X = Br, 2; NHC = IMes = 1,3-bis(2,4,6- trimethylphenyl)imidazol-2-ylidene, X = Br, 3; NHC = IBz = 1,3-dibenzylimidazol- 2-ylidene, X = Br, 4a, and X = Cl, 4b; NHC = 1-methyl-3-propylimidazol-2- ylidene, X = Br, 5) and [CpMo(CO)2(IMes)(CH3CN)][BF 4] (6) have been synthesized and fully characterized. The stability of metal-NHC ligand bonds in these compounds under oxidative conditions has been investigated. The thermally stable Mo(VI) dioxo NHC complex [CpMoO 2(IMes)][BF4] (9) has been isolated by the oxidation of the ionic complex 6 by TBHP (tert-butyl hydrogen peroxide). Complex 6 can be applied as a very active (TOFs up to 3400 h-1) and selective olefin epoxidation catalyst. While under oxidative conditions (in the presence of TBHP), compounds 1-5 decompose into imidazolium bromide and imidazolium polyoxomolybdate. The formation of polyoxomolybdate as oxidation products had not been observed in a similar epoxidation catalyzed by Mo(II) and Mo(VI) complexes. DFT studies suggest that the presence of Br- destabilizes the CpMo(VI) oxo NHC carbene species, consistent with the experimental observations. © 2010 American Chemical Society.

  16. Sí­ntesis one-pot y propiedades fotoluminiscentes de nanocristales semiconductores II-VI dopados con europio (III)

    OpenAIRE

    Planelles Aragó, José

    2012-01-01

    Esta tesis doctoral, que lleva por título: “Síntesis one-pot y propiedades fotoluminiscentes de nanocristales semiconductores II-VI dopados con europio (III)", se enmarca dentro del campo de la nanofotónica, al centrarse en la preparación y caracterización de materiales nanoestructurados cuyas propiedades físicas, especialmente las ópticas, han sido modificadas químicamente. Tal y como el propio título indica, en ella se recopilan los resultados obtenidos en el estudio de nanocristales de CdS...

  17. Pengaruh Penggunaan Media Atlas Taktual Terhadap Minat Dan Prestasi Belajar IPS Siswa Kelas IV, V, VI Semester II Slb a Negeri Denpasar Tahun Pelajaran 2014/2015

    OpenAIRE

    SITI INSIYAH; PROF. DR. A.A.ISTRI NGR.MARHAENI,M.A; PROF.DR.I NYOMAN NATAJAYA, M.Pd

    2015-01-01

    Penelitian ini bertujuan untuk mengetahui pengaruh penggunaan media atlas taktual terhadap minat dan prestasi belajar IPS pada siswa kelas IV, V, VI SLB A Negeri Denpasar. Pengumpulan data minat belajar menggunakan metode inventori minat dan pengumpulan data prestasi belajar IPS menggunakan metode tes. Subyek penelitian ini adalah siswa kelas IV, V, VI semester II SLB A Negeri Denpasar tahun pelajaran 2014/2015. Variabel bebas yang di gunakan untuk penelitian ini adalah media atlas tak...

  18. Efficient removal of Cr(VI) from wastewater under sunlight by Fe(II)-doped TiO{sub 2} spherical shell

    Energy Technology Data Exchange (ETDEWEB)

    Xu, S.C., E-mail: scxu@issp.ac.cn [Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China); Pan, S.S.; Xu, Y.; Luo, Y.Y.; Zhang, Y.X. [Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China); Li, G.H., E-mail: ghli@issp.ac.cn [Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China); University of Science and Technology of China, Hefei 230026 (China)

    2015-02-11

    Graphical abstract: - Highlights: • Fe(II)/TiO{sub 2} spherical shell catalyst was synthesized by hydrothermal method. • Cr(VI) removal effectiveness reaches to 99.99% with 102.3 ppm initial content. • TiO{sub 2}, Fe(II) and Fe{sup 0} atom synergistically contribute to Cr(VI) reduction. • Bulk Fe(II) doping enhance electron transference between TiO{sub 2} and Fe(II) ions. • Special spherical shell structure enhances the utilization of sunlight. - Abstract: Fe(II)-doped TiO{sub 2} spherical shell catalyst was synthesized by one-pot hydrothermal method. The photocatalytic removal of Cr(VI) from plating wastewater under sunlight of the catalyst was demonstrated. It was found that the removal effectiveness of about 99.99% for initial Cr(VI) concentration of 102.3 ppm and 99.01% for 153.4 ppm under 3 h sunlight irradiation is realized. The Fe(II) ions serve not only as reducing agents for reducing the Cr(VI) to Cr(III) but also as an intermedium of a two-step reduction, in which the TiO{sub 2} photoreduces the Fe(II) ions to Fe atoms firstly, and then the Fe atoms reduce the Cr(VI) to Cr(III). The improved photocatalytic activity of the catalyst is considered due to the synergistic effect of a multi reducing process by Fe(II) doping. The extended optical response and effectively utilization of sunlight of the special spherical-shell-like morphology also contribute to the enhanced photocatalytic activity.

  19. Elastico-mechanoluminescence and crystal-structure relationships in persistent luminescent materials and II-VI semiconductor phosphors

    Science.gov (United States)

    Chandra, B. P.; Chandra, V. K.; Jha, Piyush

    2015-04-01

    Elastico-mechanoluminescence (EML) has recently attracted the attention of a large number of researchers because of its potential in different types of mechano-optical devices. For understanding the mechanism of EML the relationships between elastico-mechanoluminescence (EML) and crystal-structure of a large number of persistent luminescent materials and II-VI semiconductor phosphors known to date are investigated. It is found that, although most of the non-centrosymmetric crystals exhibit EML, certain non-centrosymmetric crystals do not show EML. Whereas, many centrosymmetric crystals do not exhibit EML, certain centrosymmetric crystals exhibit EML. Piezoelectric ZnS:Cu,Cl single crystals do not show EML, but piezoelectric ZnS:Cu,Cl microcrystalline phosphors show very intense EML. Piezoelectric single crystals of undoped ZnS do not show EML. It seems that EML is related to local piezoelectrification near the impurities in crystals where piezoelectric constant is high. Suitable piezoelectric field near the local piezoelectric region and stable charge carriers in traps are required for appearance of EML. The EML of persistent luminescent materials and II-VI semiconductor phosphors can be understood on the basis of piezoelectrically-induced trap-depth reduction model of EML. Using suitable dopants both in non-centrosymmetric and centrosymmetric crystals intense elastico-mechanoluminescent materials emitting desired colours can be tailored, which may find applications in several mechano-optical devices.

  20. Adenylyl cyclase types I and VI but not II and V are selectively inhibited by nitric oxide

    Directory of Open Access Journals (Sweden)

    J. Goldstein

    2002-02-01

    Full Text Available Adenylyl cyclase (AC isoforms catalyze the synthesis of 3',5'-cyclic AMP from ATP. These isoforms are critically involved in the regulation of gene transcription, metabolism, and ion channel activity among others. Nitric oxide (NO is a gaseous product whose synthesis from L-arginine is catalyzed by the enzyme NO synthase. It has been well established that NO activates the enzyme guanylyl cyclase, but little has been reported on the effects of NO on other important second messengers, such as AC. In the present study, the effects of sodium nitroprusside (SNP, a nitric oxide-releasing compound, on COS-7 cells transfected with plasmids containing AC types I, II, V and VI were evaluated. Total inhibition (~98.5% of cAMP production was observed in COS-7 cells transfected with the AC I isoform and previously treated with SNP (10 mM for 30 min, when stimulated with ionomycin. A high inhibition (~76% of cAMP production was also observed in COS-7 cells transfected with the AC VI isoform and previously treated with SNP (10 mM for 30 min, when stimulated with forskolin. No effect on cAMP production was observed in cells transfected with AC isoforms II and V.

  1. Strain effects in the common-cation II-VI heterostructures: case of ZnS/ZnSe superlattices

    CERN Document Server

    Tit, N

    2003-01-01

    The electronic band-structures of the strained-layer ZnS/ZnSe (001) superlattices (SLs) have been investigated using the sp sup 3 s* tight-binding method, which includes the strain and spin-orbit effects. The SL band-structures are studied versus the biaxial strain, layer thickness, and band offsets. The results suggest that the common-cation II-VI heterojunction exhibit a vanishingly small conduction-band offset (CBO). It is shown that the SL valence-band top state is always a heavy-hole localized within ZnSe slabs; whereas the conduction-band edge state (electron) is sensitive to the biaxial strain (or VBO). To assess the strain effects, we considered three differently strained SLs corresponding to the three substrates: (i) ZnSe; (ii) ZnS sub 0 sub . sub 5 Se sub 0 sub . sub 5; and (iii) ZnS. The results show that all the studied SLs are of type-I except those strained to ZnS (case iii), that may exhibit type-I to type-II transition. One striking result obtained here is the existence of a critical VBO (V su...

  2. Electrical Activation of Dopant Atoms in the II-VI Materials M-X (M = Zn, Cd and X = S, Se, Te)

    CERN Multimedia

    Ostheimer, V; Lauer, S

    2002-01-01

    % IS328 \\\\ \\\\ Little is known about the properties and behaviour of intrinsic point defects and impurities in II-VI semiconductors, mainly because their identification and their mutual interactions still pose a major puzzle. Intrinsic point defects and impurities are blamed for the failure of making working p-n junction devices out of wide-band-gap semiconductors. Using the perturbed $\\gamma$

  3. Evaluation of adsorption efficiency of activated carbon/chitosan composite for removal of Cr (VI and Cd (II from single and bi-solute dilute solution

    Directory of Open Access Journals (Sweden)

    Hakimeh Sharififard

    2017-06-01

    Full Text Available The aim of this study was to evaluate the adsorption capacity of the novel coated activated carbon by chitosan for removal of Cr (VI and Cd (II ions from single and bi-solute dilute aqueous solutions. In addition, the adsorption abilities of activated carbon (AC, chitosan (CH and chitosan / activated carbon composite (CHAC have been compared. Adsorption studies were performed in a batch system, and the effects of various operating parameters such as solution pH, particle size and the dose of adsorbent were considered for removal of Cr (VI and Cd (II by Taguchi method. Equilibrium experimental data were well fitted to Langmuir isotherm for single and bi-solute solutions. The adsorption capacities of AC and CH adsorbents have improved by synthesis CHAC composite. As it was expected, competitive adsorption of metal ions on the CHAC surface led to reducing the adsorption capacity from 90.9 mg g-1 to 41.94 mg g-1 for Cr (VI and 52.63 mg g-1 to 30.21 mg g-1 for Cd (II ions, respectively. The adsorption capacities for the metal solution–adsorbent systems are in the order Cr (VI > Cd (II. The kinetic studies indicated that the adsorption process was best described by the pseudo-second-order kinetics for single and bi-solute solutions.

  4. 25 years after Vi typhoid vaccine efficacy study, typhoid affects significant number of population in Nepal.

    Science.gov (United States)

    Bajracharya, Deepak; Khan, M Imran; Pach, Alfred; Shrestha, Parisha; Joshi, Nilesh; Upreti, Shyam R; Wierzba, Thomas; Puri, Mahesh; Sahastrabuddhe, Sushant; Ochiai, R Leon

    2014-01-01

    Salmonella Typhi, first isolated in 1884, results in infection of the intestines and can end in death and disability. Due to serious adverse events post vaccination, whole cell killed vaccines have been replaced with new generation vaccines. The efficacy of Vi polysaccharide (ViPS) vaccine, a new generation, single-dose intramuscular typhoid vaccine was assessed in Nepal in 1987. However, despite the availability of ViPS vaccine for more than 25 years, Nepal has one of the highest incidence of typhoid fever. Therefore we collected information from hospitals in the Kathmandu Valley from over the past five years. There were 9901 enteric fever cases between January 2008 and July 2012. 1,881 of these were confirmed typhoid cases from five hospitals in the Kathmandu district. Approximately 70% of the cases involved children under 15 years old. 1281 cases were confirmed as S. Paratyphi. Vaccines should be prioritized for control of typhoid in conjunction with improved water and sanitation conditions in Nepal and in endemic countries of Asia and Africa.

  5. [The knowledge of the population of Viçosa, MG, about the ways of AIDS transmission].

    Science.gov (United States)

    Lima, Marcela Miranda; Carlos, Jaqueline; Areal, Rômulo Braga; Souza, Rodrigo José Silva; Lima, Swiany Silveira; Campos, Lucio Antonio de Oliveira; Eisenlohr, Pedro Vasconcellos; Filardi, Michelle Picinin

    2008-01-01

    AIDS is a major public health problem reaching all social strata. Knowing about the ways of transmission is a way of preventing the disease. For evaluating the level of knowledge of the population of the city of Viçosa about AIDS transmission, a questionnaire about the ways of transmission of the disease based on studies made in Europe was applied to 376 individuals. The questionnaire consisted of eleven multiple-choice questions about the ways of AIDS transmission, sex, age and educational level of the interviewees. The results showed that the ways of transmission emphasized in health campaigns are well assimilated, while the questions about everyday situations that offer no risk received a high number of incorrect answers. The differences were not significant when data were stratified by sex. The same data stratified by age or educational level showed significant differences for some questions; people aged over 55 and with a lower educational level had a significantly higher number of incorrect answers. It can be concluded that the population of Viçosa knows the main ways of AIDS transmission, but a part of the population does not know that some everyday situations do not pose risk of transmission. These data can be useful for the preparation of elucidative campaigns for reducing prejudice.

  6. Synthesis, spectroscopic, antimicrobial, XRD, fluorescence of new Ni(II), Cd(II), Hg(II) and U(VI) complexes with 1-(2-furylmethylene)-N-(3-phenylallylidene)methanamine Schiff base

    Science.gov (United States)

    El-Wahab, Zeinab H. Abd; Ali, Omyma A. M.; Ismail, Basma A.

    2017-09-01

    The 1:1 condensation of 2-furfurylamine and cinnamaldehyde under template condition gives the Schiff base ligand 1-(2-furylmethylene)-N-(3-phenylallylidene)methanamine (L). The reaction of the ligand with Ni(II), Cd(II), Hg(II) and U(VI) ions gives a series of novel complexes formulated as [NiLCl(H2O)]Cl·1½H2O, [CdL2(H2O)2]·2NO3·½H2O, [HgL2Cl2] and [UO2L3]·2NO3·H2O. The stoichiometry of the complexes was 1:1 for Ni(II), 1:2 for both Cd(II) and Hg(II) and 1:3 (M:L) for U(VI) complexes. The molar conductance of the complexes lies in the range of 135-250 Ω-1mol-1cm2 indicating their electrolytic behavior except Hg(II) complex. Electronic spectra and magnetic moments suggested varieties of geometries around the central metal atoms. The emission spectra of these complexes indicate the luminescence characteristics of the complexes. The X-ray diffraction (XRD) patterns of Schiff base and its complexes were investigated in powder forms. Thermodynamic parameters were computed from the thermal data using Coats and Redfern method. Structural optimization of the ligand and its Ni(II), Cd(II) and Hg(II) complexes was computed using the density functional theory (DFT), where the B3LYP functional was employed. The synthesized complexes exhibited higher antimicrobial activity than its free Schiff base ligand.

  7. Adsorption of Cr(VI) on cerium immobilized cross-linked chitosan composite in single system and coexisted with Orange II in binary system.

    Science.gov (United States)

    Zhu, Tianyi; Huang, Wei; Zhang, Lingfan; Gao, Jie; Zhang, Wenqing

    2017-10-01

    In this work, cerium immobilized cross-linked chitosan (CTS-Ce) composite, employed as an efficient adsorbent for Cr(VI) in single system and coexisted with Orange II (OII) in binary system, was prepared by co-precipitation method. The as-obtained adsorbent was characterized by FTIR, SEM, EDS and XPS before and after adsorption. The adsorption behaviors of Cr(VI) in single and binary system were systematically studied. The maximum adsorption capacity of Cr(VI) on CTS-Ce (202.8mg/g) was calculated by Langmuir equation in single metal system, but it decreased to 112.9mg/g with initial concentration of 100mg/L OII in binary system at pH 2 and 293K. The adsorption data for Cr(VI) followed the Langmuir model in single system, while fitted Temkin model well in binary system. In both single and binary system, the kinetics of adsorption exhibited pseudo-second order behavior and adsorption capacity increased with increasing temperature. Moreover, the data of thermodynamic parameters (ΔG°0) indicated that the adsorption was a spontaneous and endothermic process. Besides, |ΔGCr|>|ΔGCr-OII| at the same temperature further suggested that Cr(VI) was adsorbed on the CTS-Ce composite faster in binary system than in single system. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. ISLSCP II Global Population of the World

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Population of the World (GPW) translates census population data to a latitude-longitude grid so that population data may be used in cross-disciplinary...

  9. Functionalization of Magnetic Chitosan Particles for the Sorption of U(VI), Cu(II) and Zn(II)-Hydrazide Derivative of Glycine-Grafted Chitosan.

    Science.gov (United States)

    Hamza, Mohammed F; Aly, Mohsen M; Abdel-Rahman, Adel A-H; Ramadan, Samar; Raslan, Heba; Wang, Shengye; Vincent, Thierry; Guibal, Eric

    2017-05-16

    A new magnetic functionalized derivative of chitosan is synthesized and characterized for the sorption of metal ions (environmental applications and metal valorization). The chemical modification of the glycine derivative of chitosan consists of: activation of the magnetic support with epichlorohydrin, followed by reaction with either glycine to produce the reference material (i.e., Gly sorbent) or glycine ester hydrochloride, followed by hydrazinolysis to synthesize the hydrazide functionalized sorbent (i.e., HGly sorbent). The materials are characterized by titration, elemental analysis, FTIR analysis (Fourrier-transform infrared spectrometry), TGA analysis (thermogravimetric analysis) and with SEM-EDX (scanning electron microscopy coupled to energy dispersive X-ray analysis). The sorption performances for U(VI), Cu(II), and Zn(II) are tested in batch systems. The sorption performances are compared for Gly and HGly taking into account the effect of pH, the uptake kinetics (fitted by the pseudo-second order rate equation), and the sorption isotherms (described by the Langmuir and the Sips equations). The sorption capacities of the modified sorbent reach up to 1.14 mmol U g-1, 1.69 mmol Cu g-1, and 0.85 mmol Zn g-1. In multi-metal solutions of equimolar concentration, the chemical modification changes the preferences for given metal ions. Metal ions are desorbed using 0.2 M HCl solutions and the sorbents are re-used for five cycles of sorption/desorption without significant loss in performances.

  10. Batch sorption dynamics, kinetics and equilibrium studies of Cr(VI), Ni(II) and Cu(II) from aqueous phase using agricultural residues

    Science.gov (United States)

    Kaur, Rajvinder; Singh, Joginder; Khare, Rajshree; Cameotra, Swaranjit Singh; Ali, Amjad

    2013-03-01

    In the present study, the agricultural residues viz., Syzygium cumini and Populus deltoides leaves powder have been used for the biosorption of Cu(II), Ni(II), and Cr(VI) from aqueous solutions. FTIR and SEM analysis of the biosorbents were performed to explore the type of functional groups available for metal binding and to study the surface morphology. Various physico-chemical parameters such as pH, adsorbent dosage, initial metal ion concentration, and equilibrium contact time were studied. Thermodynamic studies were carried out and the results demonstrated the spontaneous and endothermic nature of the biosorption process. The equilibrium data were tested using four isotherm models—Langmuir, Freundlich, Temkin and Dubinin-Radushkevich and the maximum biosorption capacities were evaluated. The Pseudo-first-order, pseudo-second-order, Elovich and intraparticle diffusion models were applied to study the reaction kinetics with pseudo-second order model giving the best fit ( R 2 = 0.99) to the experimental data.

  11. Precursors for use in vapour and solution phase thermolysis routes to II-VI thin films and nanodispersed oxide materials

    CERN Document Server

    Chunggaze, M

    1999-01-01

    Monothiocarbamates M(OSCNEt sub 2) sub 2 M = Cd (1) Zn (2) analogous to the dithiocarbamates (Et sub 2 NCS sub 2) sub 2 M which have been extensively studied for metal-organic chemical vapour deposition (MOCVD), have been prepared as alternative single-source precursors for depositing II-VI semiconducting materials. Structural analysis of (1) revealed a new, O-binucleating, bonding mode for the monothiocarbamato ligand resulting in polymeric chains which are co-aligned to give a distorted close-packed hexagonal array. The mixed alkyl zinc derivative [Et sub 4 Zn sub 4 (OSCNEt sub 2) sub 2 (NEt sub 2) sub 2] is formed as the only isolable product from the reaction of EtZnNEt sub 2 with carbonyl sulfide and also exhibits a second new bonding mode for the monothiocarbamato ligand in which both the oxygen and sulfur atoms are binucleating. Uniform adherent films of CdS films with various morphologies were grown on GaAs(100) and glass at substrate temperatures between 350-450 deg C. No oxygen incorporation within ...

  12. Transforming common III-V/II-VI insulating building blocks into topological heterostructure via the intrinsic electric polarization

    Science.gov (United States)

    Zunger, Alex; Zhang, Xiuwen; Abdalla, Leonardo; Liu, Qihang

    Currently known topological insulators (TIs) are limited to narrow gap compounds incorporating heavy elements, thus severely limiting the material pool available for such applications. We show how a heterovalent superlattice made of common semiconductor building blocks can transform its non-TI components into a topological heterostructure. The heterovalent nature of such interfaces sets up, in the absence of interfacial atomic exchange, a natural internal electric field that along with the quantum confinement leads to band inversion, transforming these semiconductors into a topological phase while also forming a giant Rashba spin splitting. We demonstrate this paradigm of designing TIs from ordinary semiconductors via first-principle calculations on III-V/II-VI superlattice InSb/CdTe. We illustrate the relationship between the interfacial stability and the topological transition, finding a ``window of opportunity'' where both conditions can be optimized. This work illustrates the general principles of co-evaluation of TI functionality with thermodynamic stability as a route of identifying realistic combination of common insulators that could produce topological heterostructures. This work was supported by Basic Energy Science, MSE division (Grant DE-FG02-13ER46959).

  13. Magnetism in the p-type Monolayer II-VI semiconductors SrS and SrSe

    Science.gov (United States)

    Lin, Heng-Fu; Lau, Woon-Ming; Zhao, Jijun

    2017-01-01

    Using density functional theory calculations, we study the electronic and magnetic properties of the p-type monolayer II-VI semiconductors SrX (X = S,Se). The pristine SrS and SrSe monolayers are large band gap semiconductor with a very flat band in the top valence band. Upon injecting hole uniformly, ferromagnetism emerges in those system in a large range of hole density. By varying hole density, the systems also show complicated phases transition among nonmagnetic semiconductor, half metal, magnetic semiconductor, and nonmagnetic metal. Furthermore, after introducing p-type dopants in SrS and SrSe via substitutionary inserting P (or As) dopants at the S (or Se) sites, local magnetic moments are formed around the substitutional sites. The local magnetic moments are stable with the ferromagnetic order with appreciable Curie temperature. The ferromagnetism originates from the instability of the electronic states in SrS and SrSe with the large density of states at the valence band edge, which demonstrates a useful strategy for realizing the ferromagnetism in the two dimensional semiconductors. PMID:28378761

  14. Bioengineered II-VI semiconductor quantum dot-carboxymethylcellulose nanoconjugates as multifunctional fluorescent nanoprobes for bioimaging live cells

    Science.gov (United States)

    Mansur, Alexandra A. P.; Mansur, Herman S.; Mansur, Rafael L.; de Carvalho, Fernanda G.; Carvalho, Sandhra M.

    2018-01-01

    Colloidal semiconductor quantum dots (QDs) are light-emitting ultra-small nanoparticles, which have emerged as a new class of nanoprobes with unique optical properties for bioimaging and biomedical diagnostic. However, to be used for most biomedical applications the biocompatibility and water-solubility are mandatory that can achieved through surface modification forming QD-nanoconjugates. In this study, semiconductor II-VI quantum dots of type MX (M = Cd, Pb, Zn, X = S) were directly synthesized in aqueous media and at room temperature using carboxymethylcellulose sodium salt (CMC) behaving simultaneously as stabilizing and surface biofunctional ligand. These nanoconjugates were extensively characterized using UV-visible spectroscopy, photoluminescence spectroscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy, dynamic light scattering and zeta potential. The results demonstrated that the biopolymer was effective on nucleating and stabilizing the colloidal nanocrystals of CdS, ZnS, and PbS with the average diameter ranging from 2.0 to 5.0 nm depending on the composition of the semiconductor core, which showed quantum-size confinement effect. These QD/polysaccharide conjugates showed luminescent activity from UV-visible to near-infrared range of the spectra under violet laser excitation. Moreover, the bioassays performed proved that these novel nanoconjugates were biocompatible and behaved as composition-dependent fluorescent nanoprobes for in vitro live cell bioimaging with very promising perspectives to be used in numerous biomedical applications and nanomedicine.

  15. Normal and reverse defect annealing in ion implanted II-VI oxide semiconductors

    Science.gov (United States)

    Azarov, Alexander; Galeckas, Augustinas; Wendler, Elke; Ellingsen, Josef; Monakhov, Edouard; Svensson, Bengt G.

    2017-09-01

    Post-implantation annealing is typically used to remove structural defects and electrically activate implanted dopants in semiconductors. However, ion-induced defects and their interaction with dopants in group II oxide semiconductors are not fully understood. Here, we study defect evolution in the course of annealing in CdO and ZnO materials implanted with nitrogen which is one of the most promising candidates for p-type doping. The results of photoluminescence and ion channeling measurements revealed a striking difference in defect behavior between CdO and ZnO. In particular, the defect annealing in CdO exhibits a two stage behavior, the first stage accounting for efficient removal of point defects and small defect clusters, while the second one involves gradual disappearance of extended defects where the sample decomposition can play a role. In contrast, a strong reverse annealing occurs for ZnO with a maximum defect concentration around 900 °C. This effect occurs exclusively for nitrogen ions and is attributed to efficient growth of extended defects promoted by the presence of nitrogen.

  16. Time-resolved ultrafast spectroscopy of wide-gap II-VI semiconductor quantum wells

    CERN Document Server

    Brown, G

    2001-01-01

    proposal is supported through the development of a phenomenological model describing the dynamic evolution of exciton spin populations. The inclusion of higher order Coulomb interaction terms within current many-body theory is limited by the analytical complexity This work provides valuable experimental observations, which invite further theoretical endeavour within this field. Ultrafast spectroscopic techniques have been used out to investigate both coherent and incoherent exciton dynamics within zinc selenide-based multiple quantum wells. Time-integrated four-wave-mixing experiments were carried out to investigate exciton dephasing due to exciton-phonon scattering. In particular experiments on multiple quantum well structures with a range of well widths demonstrated that exciton-acoustic phonon scattering was found to reach a maximum when the quantum confinement within the well was also maximised. The technique of pump-continuum probe spectroscopy has been enhanced giving improved resolution of absorption d...

  17. The reactivity of Fe(II) associated with goethite formed during short redox cycles toward Cr(VI) reduction under oxic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Tomaszewski, Elizabeth J.; Lee, Seungyeol; Rudolph, Jared; Xu, Huifang; Ginder-Vogel, Matthew (UW)

    2017-08-01

    Chromium (Cr) is a toxic metal that causes a myriad of health problems and enters the environment as a result of anthropogenic activities and/or natural processes. The toxicity and solubility of chromium is linked to its oxidation state; Cr(III) is poorly soluble and relatively nontoxic, while Cr(VI) is soluble and a known carcinogen. Solid Fe(II) in iron-bearing minerals, such as pyrite, magnetite, and green rusts, reduce the oxidation state of chromium, reducing its toxicity and mobility. However, these minerals are not the only potential sources of solid-associated Fe(II) available for Cr(VI) reduction. For example, ferric (Fe(III)) (hydr)oxides, such as goethite or hematite, can have Fe(II) in the solid without phase transformation; however, the reactivity of Fe(II) within Fe(III) (hydr)oxides with contaminants, has not been previously investigated. Here, we cyclically react goethite with dissolved Fe(II) followed by dissolved O2, leading to the formation of reactive Fe(II) associated with goethite. In separate reactors, the reactivity of this Fe(II) is probed under oxic conditions, by exposure to chromate (CrO42 -) after either one, two, three or four redox cycles. Cr is not present during redox cycling; rather, it is introduced to a subset of the solid after each oxidation half-cycle. Analysis of X-ray absorption near edge structure (XANES) spectra reveals that the extent of Cr(VI) reduction to Cr(III) depends not only on solid Fe(II) content but also surface area and mean size of ordered crystalline domains, determined by BET surface area analysis and X-ray diffraction (XRD), respectively. Shell-by-shell fitting of the extended X-ray absorption fine structure (EXAFS) spectra demonstrates chromium forms both single and double corner sharing complexes on the surface of goethite, in addition to sorbed Cr(III) species. Finally, transmission electron microscope (TEM) imaging and X-ray energy-dispersive spectroscopy (EDS) illustrate that Cr preferentially

  18. Bioengineered II-VI semiconductor quantum dot-carboxymethylcellulose nanoconjugates as multifunctional fluorescent nanoprobes for bioimaging live cells.

    Science.gov (United States)

    Mansur, Alexandra A P; Mansur, Herman S; Mansur, Rafael L; de Carvalho, Fernanda G; Carvalho, Sandhra M

    2018-01-15

    Colloidal semiconductor quantum dots (QDs) are light-emitting ultra-small nanoparticles, which have emerged as a new class of nanoprobes with unique optical properties for bioimaging and biomedical diagnostic. However, to be used for most biomedical applications the biocompatibility and water-solubility are mandatory that can achieved through surface modification forming QD-nanoconjugates. In this study, semiconductor II-VI quantum dots of type MX (M=Cd, Pb, Zn, X=S) were directly synthesized in aqueous media and at room temperature using carboxymethylcellulose sodium salt (CMC) behaving simultaneously as stabilizing and surface biofunctional ligand. These nanoconjugates were extensively characterized using UV-visible spectroscopy, photoluminescence spectroscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy, dynamic light scattering and zeta potential. The results demonstrated that the biopolymer was effective on nucleating and stabilizing the colloidal nanocrystals of CdS, ZnS, and PbS with the average diameter ranging from 2.0 to 5.0nm depending on the composition of the semiconductor core, which showed quantum-size confinement effect. These QD/polysaccharide conjugates showed luminescent activity from UV-visible to near-infrared range of the spectra under violet laser excitation. Moreover, the bioassays performed proved that these novel nanoconjugates were biocompatible and behaved as composition-dependent fluorescent nanoprobes for in vitro live cell bioimaging with very promising perspectives to be used in numerous biomedical applications and nanomedicine. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Photoinduced electron donor/acceptor processes in colloidal II-VI semiconductor quantum dots and nitroxide free radicals

    Science.gov (United States)

    Dutta, Poulami

    Electron transfer (ET) processes are one of the most researched topics for applications ranging from energy conversion to catalysis. An exciting variation is utilizing colloidal semiconductor nanostructures to explore such processes. Semiconductor quantum dots (QDs) are emerging as a novel class of light harvesting, emitting and charge-separation materials for applications such as solar energy conversion. Detailed knowledge of the quantitative dissociation of the photogenerated excitons and the interfacial charge- (electron/hole) transfer is essential for optimization of the overall efficiency of many such applications. Organic free radicals are the attractive counterparts for studying ET to/from QDs because these undergo single-electron transfer steps in reversible fashion. Nitroxides are an exciting class of stable organic free radicals, which have recently been demonstrated to be efficient as redox mediators in dye-sensitized solar cells, making them even more interesting for the aforementioned studies. This dissertation investigates the interaction between nitroxide free radicals TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl), 4-amino-TEMPO (4-amino- 2,2,6,6-tetramethylpiperidine-1-oxyl) and II-VI semiconductor (CdSe and CdTe) QDs. The nature of interaction in these hybrids has been examined through ground-state UV-Vis absorbance, steady state and time-resolved photoluminescence (PL) spectroscopy, transient absorbance, upconversion photoluminescence spectroscopy and electron paramagnetic resonance (EPR). The detailed analysis of the PL quenching indicates that the intrinsic charge transfer is ultrafast however, the overall quenching is still limited by the lower binding capacities and slower diffusion related kinetics. Careful analysis of the time resolved PL decay kinetics reveal that the decay rate constants are distributed and that the trap states are involved in the overall quenching process. The ultrafast hole transfer from CdSe QDs to 4-Amino TEMPO observed

  20. Analysis of MBE-grown II-VI hetero-interfaces and quantum-dots by Raman spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Bass, Utz

    2012-10-16

    The material system of interest in this thesis are II-VI-semiconductors. The first part of this thesis focuses on the formation of self-assembled CdSe-based quantum dots (QD) on ZnSe. The lattice constants of ZnSe and CdSe differ as much as about 7% and therefore a CdSe layer grown on top of ZnSe experiences a huge strain. The aspired strain relief constitutes in the self-assembly of QDs (i.e. a roughened layer structure). Additionally, this QD layer is intermixed with Zn as this is also a possibility to decrease the strain in the layer. For CdSe on ZnSe, in Molecular Beam Epitaxy (MBE), various QD growth procedures were analysed with respect to the resulting Cd-content of the non-stoichiometric ternary (Zn,Cd)Se. The evaluation was performed by Raman Spectroscopy as the phonon frequency depends on the Cd-content. The second part of the thesis emphasis on the interface properties of n-ZnSe on n-GaAs. Different growth start procedures of the ZnSe epilayer may lead to different interface configurations with characteristic band-offsets and carrier depletion layer widths. The analysis is mainly focused on the individual depletion layer widths in the GaAs and ZnSe. This non-destructive analysis is performed by evaluating the Raman signal which comprises of phonon scattering from the depleted regions and coupled plasmon-phonon scattering from regions with free carriers.

  1. Sn(II) oxy-hydroxides as potential adsorbents for Cr(VI)-uptake from drinking water: An X-ray absorption study.

    Science.gov (United States)

    Pinakidou, Fani; Kaprara, Efthimia; Katsikini, Maria; Paloura, Eleni C; Simeonidis, Konstantinos; Mitrakas, Manassis

    2016-05-01

    The feasibility of implementing a Sn(II) oxy-hydroxide (Sn6O4(OH)4) for the reduction and adsorption of Cr(VI) in drinking water treatment was investigated using XAFS spectroscopies at the Cr-K-edge. The analysis of the Cr-K-edge XANES and EXAFS spectra verified the effective use of Sn6O4(OH)4 for successful Cr(VI) removal. Adsorption isotherms, as well as dynamic Rapid Small Scale Test (RSSCT) in NSF water matrix showed that Sn6O4(OH)4 can decrease Cr(VI) concentration below the upcoming regulation limit of 10μg/L for drinking water. Moreover, an uptake capacity of 7.2μg/mg at breakthrough concentration of 10μg/L was estimated from the RSSCT, while the residual Cr(VI) concentration ranged at sub-ppb level for a significant period of the experiment. Furthermore, no evidence for the formation of Cr(OH)3 precipitates was found. On the contrary, Cr(III)-oxyanions were chemisorbed onto SnO2, which was formed after Sn(II)-oxidation during Cr(VI)-reduction. Nevertheless, changes in the type of Cr(III)-inner sphere complexes were observed after increasing surface coverage: Cr(III)-oxyanions preferentially sorb in a geometry which combines both bidentate binuclear ((2)C) and monodentate ((1)V) geometries, at the expense of the present bidentate mononuclear ((2)E) contributions. On the other hand, the pH during sorption does not affect the adsorption mechanism of Cr(III)-species. The implementation of Sn6O4(OH)4 in water treatment technology combines the advantage of rapidly reducing a large amount of Cr(VI) due to donation of two electrons by Sn(II) and also the strong chemisorption of Cr(III) in a combination of the (2)C and (1)V configurations, which enhances the safe disposal of spent adsorbents. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Redox polymer as an adsorbent for the removal of chromium (VI) and lead (II) from the tannery effluents

    OpenAIRE

    V. Vetriselvi; Jaya Santhi, R.

    2015-01-01

    Polymer-based hybrid was widely fabricated and applied in heavy metal removal and other inorganic pollutants. The present study deals with the sorption efficiency of metal adsorption through the chemically modified PAA with dihydroxybenzenes into the polymeric matrix present in the tannery effluents and a parallel investigation of chromium (VI) ions in aqueous solution was carried out. From the Langmuir model the removal of chromium (VI) has the maximum adsorption capacity with 181.4 mg g−1. ...

  3. Determinación de trazas de Molibdeno (VI, Níquel (II y Vanadio (V en cementos por polarografía diferencial de impulsos

    Directory of Open Access Journals (Sweden)

    Gaspar-Tebar, Demetrio

    1985-09-01

    Full Text Available In this work an account is given of the results obtained when the differential pulse polarography (differential pulse anodic stripping voltametry is applied to the determination of the contents of the compounds by molybdenum (VI, nickel (II and vanadium (V in a common portland cement which are in quantities of the order of p.p.m. Those studies show that it is not possible to determine simultaneaously the content of the three mentioned ions in the cement, but if working in acid medium (hydrochloridric and sulphuric, in ammoniacal or cyanided medium and in basic medium (produced by NaHCO3 polagrogrammes are obtained which allow to complete those mentioned determinations of Mo (VI in the first medium, of Ni (II in the second and of V(V in the third. Because of the high sensibility of the polarography it is possible to determine the Ni (II which is found in quantities from 2.9 to 3.4 p.p.m. (0.0002g to 0.00034 %, in mass.

    En el presente trabajo se da cuenta de los resultados obtenidos cuando se aplica la polarografía diferencial de impulsos a la determinación de los contenidos de compuestos a base de molibdeno (VI, níquel (II y vanadio (V en un cemento portland industrial; dichos contenidos se encuentran en cantidades del orden de p.p.m. En los estudios realizados se ha puesto de manifiesto que no es posible determinar simultáneamente el contenido de los tres iones mencionados en el cemento, pero que trabajando en medio ácido (clorhídrico o sulfúrico, en medio amoniacal o cianurado y en medio básico (producido por NaHCO3 se obtienen polarogramas que permiten realizar las mencionadas determinaciones cuantitativas de Mo (VI en el primer medio, de Ni (II en el segundo y de V (V en el tercero. Gracias a la alta sensibilidad de la polarografía ha sido posible determinar la concentración de Ni (II en el cemento estudiado, que se encuentra en cantidades comprendidas entre 2,9 y 3,4 p.p.m. (0

  4. Tracking correlated, simultaneously evolving target populations, II

    Science.gov (United States)

    Mahler, Ronald

    2017-05-01

    This paper is the sixth in a series aimed at weakening the independence assumptions that are typically presumed in multitarget tracking. Earlier papers investigated Bayes …lters that propagate the correlations between two evolving multitarget systems. Last year at this conference we attempted to derive PHD …lter-type approximations that account for both spatial correlation and cardinality correlation (i.e., correlation between the target numbers of the two systems). Unfortunately, this approach required heuristic models of both clutter and target appearance in order to incorporate both spatial and cardinality correlation. This paper describes a fully rigorous approach- provided, however, that spatial correlation between the two populations is ignored and only their cardinality correlations are taken into account. We derive the time-update and measurement-update equations for a CPHD …lter describing the evolution of such correlated multitarget populations.

  5. Biomedical Social Science, Unit VI: Population Growth and Genetic Engineering. Student Text. Revised Version, 1977.

    Science.gov (United States)

    Biomedical Interdisciplinary Curriculum Project, Berkeley, CA.

    This collection of lessons and class activities covers two major concepts: (1) population growth and (2) genetic engineering. Lessons consist of readings, questions and answers, and problems of projects where appropriate. Issues are posed in as much as possible in a manner intended to cause the student to reach conclusions and values without being…

  6. Sn(II) oxy-hydroxides as potential adsorbents for Cr(VI)-uptake from drinking water: An X-ray absorption study

    Energy Technology Data Exchange (ETDEWEB)

    Pinakidou, Fani; Kaprara, Efthimia [Aristotle University of Thessaloniki, School of Chemical Engineering, Analytical Chemistry Laboratory, 54124 Thessaloniki (Greece); Katsikini, Maria; Paloura, Eleni C.; Simeonidis, Konstantinos [Aristotle University of Thessaloniki, School of Physics, Department of Solid State Physics, 54124 Thessaloniki (Greece); Mitrakas, Manassis, E-mail: manasis@eng.auth.gr [Aristotle University of Thessaloniki, School of Chemical Engineering, Analytical Chemistry Laboratory, 54124 Thessaloniki (Greece)

    2016-05-01

    The feasibility of implementing a Sn(II) oxy-hydroxide (Sn{sub 6}O{sub 4}(OH){sub 4}) for the reduction and adsorption of Cr(VI) in drinking water treatment was investigated using XAFS spectroscopies at the Cr-K-edge. The analysis of the Cr-K-edge XANES and EXAFS spectra verified the effective use of Sn{sub 6}O{sub 4}(OH){sub 4} for successful Cr(VI) removal. Adsorption isotherms, as well as dynamic Rapid Small Scale Test (RSSCT) in NSF water matrix showed that Sn{sub 6}O{sub 4}(OH){sub 4} can decrease Cr(VI) concentration below the upcoming regulation limit of 10 μg/L for drinking water. Moreover, an uptake capacity of 7.2 μg/mg at breakthrough concentration of 10 μg/L was estimated from the RSSCT, while the residual Cr(VI) concentration ranged at sub-ppb level for a significant period of the experiment. Furthermore, no evidence for the formation of Cr(OH){sub 3} precipitates was found. On the contrary, Cr(III)-oxyanions were chemisorbed onto SnO{sub 2}, which was formed after Sn(II)-oxidation during Cr(VI)-reduction. Nevertheless, changes in the type of Cr(III)-inner sphere complexes were observed after increasing surface coverage: Cr(III)-oxyanions preferentially sorb in a geometry which combines both bidentate binuclear ({sup 2}C) and monodentate ({sup 1}V) geometries, at the expense of the present bidentate mononuclear ({sup 2}E) contributions. On the other hand, the pH during sorption does not affect the adsorption mechanism of Cr(III)-species. The implementation of Sn{sub 6}O{sub 4}(OH){sub 4} in water treatment technology combines the advantage of rapidly reducing a large amount of Cr(VI) due to donation of two electrons by Sn(II) and also the strong chemisorption of Cr(III) in a combination of the {sup 2}C and {sup 1}V configurations, which enhances the safe disposal of spent adsorbents. - Highlights: • Effective Cr(VI) removal from drinking water by Sn{sub 6}O{sub 4}(OH){sub 4} • Sn{sub 6}O{sub 4}(OH){sub 4} transformation to SnO{sub 2} after Cr(VI

  7. Metal-Dimer Atomic Reconstruction Leading to Deep Donor States of the Anion Vacancy in II-VI and Chalcopyrite Semiconductors

    Science.gov (United States)

    Lany, Stephan; Zunger, Alex

    2004-10-01

    First-principles total-energy calculations reveal a novel local atomic reconstruction mode around anion vacancies in II-VI and chalcopyrite compounds resulting from the formation of metal dimers. As a consequence, the neutral Se vacancy has an unexpected low symmetry in ZnSe and becomes a deep donor in both ZnSe and CuGaSe2, contrary to the common belief regarding chalcopyrites. The calculated optical transition energies explain the hitherto puzzling absorption bands observed in the classic experiments of the color center in ZnS.

  8. Multicolor (UV-IR) Photodetectors Based on Lattice-Matched 6.1 A II/VI and III/V Semiconductors

    Science.gov (United States)

    2015-08-27

    infrared multi-color photodetector based on II-VI and III-V semiconductors. This photodetector consists of a newly-proposed CdTe /ZnTe/ CdTe nBn sub...perfectly conductive n- CdTe /p-InSb tunnel junction. 15. SUBJECT TERMS optical biasing; multi-junction photodetectors; triple-junction solar cell...Figure from Ref. [7].  Large-signal characteristics are measured with a single 780 nm laser diode at 100% modulation factor and 50% duty cycle [7

  9. Investigation of electrochemical synthesis of ferrate - Part II: Optimization of the process parameters of ferrate(VI electrochemical synthesis

    Directory of Open Access Journals (Sweden)

    Čekerevac Milan I.

    2010-01-01

    Full Text Available In part I [1] of the investigation the behavior of iron and selected low carbon steels in concentrated (10M - 15 M water solution of NaOH and KOH in wide range of electrode potentials, between hydrogen evolution reaction and oxygen evolution reaction, is investigated and discussed. On the base of experimental data obtained by LSV and galvanostatic pulse methods, it is concluded [1] that efficient synthesis of ferrate (VI can be expected in the region of anodic potentials between + 0,55 V and + 0,75 V against Hg|HgO reference electrode. In this paper optimization of electrolysis parameters of the electrochemical synthesis of ferrate(VI is elaborated. The most important parameters chosen for optimization process were: anode material, alkaline electrolyte concentration, regime of electrical potential control, current density and electrolyte temperature. The best current efficiency and yield of ferrate(VI synthesis of the explored anode materials (electrical steel, low carbon cold rolled steel plate, and structural steel is obtained when electrical steel with 3 wt% of silicon is applied. The worst current efficiency is obtained with anodes made of structural steel with higher concentration of manganese, chromium and nickel. The influence of alloying elements on the process of electrochemical synthesis of ferrate(VI is discussed in terms of their influence on formation and stability of anodic passive layer and oxygen evolution reaction. The increase of electrolyte concentration from 10M to 15M NaOH and KOH provided the increase of current efficiency with maximum obtained for 14M NaOH. The yield of ferrate(VI synthesis increases with temperature raise, having maximal value at about +50°C, and after that, at higher temperatures, instability of ferrate(VI increases and the yield of synthesis lessens. Considering the influence of electrical regime control it is concluded that the biggest yield of ferrate(VI can be expected with constant anodic potential

  10. The Populations of Carina. II. Chemical Enrichment

    Energy Technology Data Exchange (ETDEWEB)

    Norris, John E.; Yong, David; Casagrande, Luca; Dotter, Aaron [Research School of Astronomy and Astrophysics, The Australian National University, Canberra, ACT 2611 (Australia); Venn, Kim A. [Department of Physics and Astronomy, University of Victoria, 3800 Finnerty Road, Victoria, BC V8P 1A1 (Canada); Gilmore, Gerard, E-mail: jen@mso.anu.edu.au, E-mail: yong@mso.anu.edu.au, E-mail: luca@mso.anu.edu.au, E-mail: aaron.dotter@gmail.com, E-mail: kvenn@uvic.ca, E-mail: gil@ast.cam.ac.uk [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom)

    2017-06-01

    Chemical abundances are presented for 19 elements in a sample of 63 red giants in the Carina dwarf spheroidal galaxy (dSph), based on homogeneous 1D/LTE model atmosphere analyses of our own observations (32 stars) and data available in the literature (a further 31 independent stars). The (Fe) metallicity and [ α /Fe] distribution functions have mean values and dispersions of −1.59 and 0.33 dex ([Fe/H] range: −2.68 to −0.64) and 0.07 and 0.13 dex ([ α /Fe] range: −0.27 to 0.25), respectively. We confirm the finding of Venn et al. that a small percentage (some 10% in the present investigation) of the sample shows clear evidence for significant enrichment by Type Ia supernova (SN Ia) ejecta. Calcium, with the most accurately determined abundance of the α -elements, shows an asymmetric distribution toward smaller values of [Ca/Fe] at all [Fe/H], most significantly over −2.0 < [Fe/H] < −1.0, suggestive of incomplete mixing of the ejecta of SNe Ia with the ambient medium of each of Carina’s generations. Approximate color–magnitude diagram age estimates are presented for the sample, and together with our chemical abundances, compared with the results of our previous synthetic color–magnitude diagram analysis, which reported the details of Carina’s four well-defined populations. We searched for the Na–O anticorrelation universally reported in the Galaxy’s globular clusters and confirm that this phenomenon does not exist in Carina. We also found that one of the 32 stars in our sample has an extremely enhanced lithium abundance— A (Li){sub NLTE} = +3.36, consistent with membership of the ∼1% group of Li-rich stars in dSph described by Kirby et al.

  11. Kinetics and Mechanism of Paracetamol Oxidation by Chromium(VI in Absence and Presence of Manganese(II and Sodiumdodecyl Sulphate

    Directory of Open Access Journals (Sweden)

    Maqsood Ahmad Malik

    2007-11-01

    Full Text Available The kinetics of paracetamol oxidation are first order each in [paracetamol] and [HClO4]. The kinetic study shows that the oxidation proceeds in two steps. The effects of anionic micelles of sodiumdodecyl sulphate (SDS and complexing agents (ethylenediammine tetraacetic acid (EDTA and 2,2′-bipyridyl (bpy were also studied. Fast kinetic spectrophotometric method has been described for the determination of paracetamol. The method is based on the catalytic effect of manganese(II on the oxidation of paracetamol by chromium(VI in the presence of HClO4 (= 0.23 mol dm−3. Optimum reaction time is 4 to 6 minutes at a temperature of 30∘C. The addition of manganese(II ions largely decreased the absorbance of chromium(VI at 350 nm. This reaction can be utilized for the determination of paracetamol in drugs.

  12. Empirical Study of the Disparity in Radiation Tolerance of the Minority-Carrier Lifetime Between II-VI and III-V MWIR Detector Technologies for Space Applications

    Science.gov (United States)

    Jenkins, Geoffrey D.; Morath, Christian P.; Cowan, Vincent M.

    2017-09-01

    The degradation of the minority-carrier recombination lifetime of various III-V nB n and II-VI HgCdTe midwave-infrared space detector materials under stepwise 63-MeV proton irradiation up to fluence of 7.5 × 1011 cm-2 and above has been measured using time-resolved photoluminescence while samples were held at 120 K to limit thermal annealing. As expected, the recombination rate of each sample was found to increase with proton fluence at a nearly constant rate, implying a near-linear increase in defect concentration. The rate of change of the carrier recombination rate, herein called the minority-carrier lifetime damage factor, was then plotted as a function of the initial recombination rate for each sample. Juxtaposing the III-V and II-VI results revealed a distinct disparity, with the incumbent detector material HgCdTe being roughly an order of magnitude more radiation tolerant to displacement damage from proton irradiation than any of the nB n materials. The results for the latter also suggest some degree of interrelation between the damage factor and initial lifetime. The behavior of the lifetime of each material under annealing revealed that HgCdTe exhibited nearly 100% recovery at 295 K whereas III-V materials recovered to only about 50% under the same conditions.

  13. Immunogold fine structural localization of extracellular matrix components in aged human cornea. II. Collagen types V and VI.

    Science.gov (United States)

    Marshall, G E; Konstas, A G; Lee, W R

    1991-01-01

    Using immunogold immunocytochemical techniques we studied the distribution of collagen types V and VI in corneal tissue from seven enucleated human eyes (age range, 63-78 years). Results obtained by cryoultramicrotomy were marginally more intense than those obtained using London Resin white (LR white) embedding. Type V collagen was present in the striated collagen fibrils in Bowman's layer, in the stroma and in a thin, non-banded anterior zone of Descemet's membrane. Our results suggest that types I, III and V collagen co-distribute in striated collagen fibrils. By contrast, type VI collagen was located in fine filaments in the interfibrillar matrix of the stroma, in Bowman's layer and in the anchoring plaques of the sub-epithelial basement-membrane complex. This implies an importance in epithelial adhesion which was previously unsuspected. Keratocyte bodies were electron-dense, amorphous extracellular deposits of matrix-like material, and these were labelled with types III, V and VI collagen antibodies. Long-spacing collagen was observed in the corneal stroma, and this deposit did not contain any of the collagen types studied.

  14. VI Nukitsa konkurss

    Index Scriptorium Estoniae

    2002-01-01

    VI Nukitsa konkursi auhinnad: Kirjanikud: I - Henno Käo ("Kusagil mujal"); II - Aidi Vallik ("Kuidas elad, Ann?"); III - Artur Jurin ("Piletijaht: uued segadused Kilulibeda teel"). Kunstnikud: I - Karel Korp (Leelo Tungla ja Karel Korbi "Tema amet"); II - Edgar Valter ("Kuidas õppida vaatama?"); III - Artur Jurin - ("Piletijaht: uued segadused Kilulibeda teel"). Täiskasvanute küsitluse võitis nii teksti kui piltidega Ene-Maris Tali ja Tarmo Tali "Tähtraamat. Aastaring Maarjamaal"

  15. Growth and characterization of ZnCdMgSe-based green light emitters and distributed Bragg reflectors towards II-VI based semiconductor disk lasers

    Energy Technology Data Exchange (ETDEWEB)

    De Jesus, Joel; Gayen, Swapan K. [The Graduate Center, City University of New York (CUNY), New York, NY (United States); Department of Physics, The City College of New York, New York, NY (United States); Garcia, Thor A.; Tamargo, Maria C. [The Graduate Center, City University of New York (CUNY), New York, NY (United States); Department of Chemistry, The City College of New York, New York, NY (United States); Kartazaev, Vladimir [Department of Physics, The City College of New York, New York, NY (United States); Jones, Brynmor E.; Schlosser, Peter J.; Hastie, Jennifer E. [Institute of Photonics, University of Strathclyde, Glasgow (United Kingdom)

    2015-02-01

    We report the structural and optical properties of molecular beam epitaxy grown II-VI semiconductor multiple quantum well (MQW) structures and distributed Bragg reflector (DBR) on InP substrates for application in developing optically-pumped semiconductor disk lasers (SDLs) operating in the green spectral range. One sample was grown directly on an InP substrate with an InGaAs buffer layer, while another had a 5-period ZnCdMgSe-based DBR grown on the InGaAs/InP substrate. X-ray diffraction and scanning electron microscopy measurements revealed sharp superlattice peaks and abrupt layer interfaces, while steady-state photoluminescence measurements demonstrated surface emission between 540-570 nm. Under pulsed excitation both samples exhibited features of amplified spontaneous emission (ASE) or stimulated emission, accompanied by luminescence lifetime shortening. The sample with the DBR showed higher surface luminescence and the onset of ASE at lower pump power. To further explore the design and performance of a ZnCdMgSe-based DBR, a 20-period DBR was grown and a reflectivity of 83% was obtained at ∝560 nm. We estimate that a DBR with ∝40 periods would be needed for optimal performance in a SDL using these materials. These results show the potential of II-VI MQW structures on InP substrates for the development of SDLs operational in the green-yellow wavelength range. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  16. Geometry VI

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 8. Geometry VI - Space-the Final Frontier. Kapil H Paranjape. Series Article Volume 1 Issue 8 August 1996 pp 28-33. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/001/08/0028-0033 ...

  17. VI KA’

    DEFF Research Database (Denmark)

    Sprogøe, Jonas

    2012-01-01

    Artiklen handler om hvordan man kan bruge et spil til at udvikle og måle kompetencer. Artiklen diskuterer forskellige forståelser kompetencebegrebet og diskuterer hvordan Vi Ka'-spillet bidrager til at indfange den mere aktive forståelse af kompetence, som noget du gør i en bestemt kontekst....

  18. Raman spectra of Cu{sub 2}B{sup II}C{sup IV}X{sub 4}{sup VI} magnetic quaternary semiconductor compounds with tetragonal stannite type structure

    Energy Technology Data Exchange (ETDEWEB)

    Rincón, C., E-mail: crincon@ula.ve; Quintero, M.; Power, Ch.; Moreno, E.; Quintero, E.; Morocoima, M. [Centro de Estudios de Semiconductores, Departamento de Física, Facultad de Ciencias, Universidad de Los Andes, Mérida (Venezuela, Bolivarian Republic of); Henao, J. A.; Macías, M. A. [Grupo de Investigación en Química Estructural, Facultad de Ciencias, Escuela de Química, Universidad Industrial de Santander, Apartado Aéreo 678, Bucaramanga (Colombia)

    2015-05-28

    A comparative study of the Raman spectra of Cu{sub 2}B{sup II}C{sup IV}S{sub 4}{sup VI} and Cu{sub 2}B{sup II}C{sup IV}Se{sub 4}{sup VI}(where B = Mn or Fe) magnetic quaternary semiconductor compounds with stannite-type structure (I4{sup ¯}2m) has been done. Most of the fourteen Raman lines expected for these materials were observed in the spectra. The two strongest lines observed have been assigned to the IR inactive A{sub 1}{sup 1} and A{sub 1}{sup 2} stannite modes that originated from the motion of the S or Se anion around the Cu and C{sup IV} cations remaining at rest. The shift in the frequency of these two lines of about 150 cm{sup −1} to lower energies observed in Cu{sub 2}B{sup II}C{sup IV}Se{sub 4}{sup VI} compounds as compared to those in Cu{sub 2}B{sup II}C{sup IV}S{sub 4}{sup VI} ones, can then be explained as due to the anion mass effect. Based on the fact that values of these frequencies depend mainly on anion mass and bond-stretching forces between nearest-neighbor atoms, the vibrational frequencies v{sup ¯}(A{sub 1}{sup 2}) and v{sup ¯}(A{sub 1}{sup 2}) of both modes for several Cu{sub 2}B{sup II}C{sup IV}X{sub 4}{sup VI} stannite compounds (where X = S, Se, or Te) very close to the experimental data reported for these materials were calculated from a simple model that relates these stretching forces to the anion-cation bond-distances.

  19. Functionalization of Magnetic Chitosan Particles for the Sorption of U(VI, Cu(II and Zn(II—Hydrazide Derivative of Glycine-Grafted Chitosan

    Directory of Open Access Journals (Sweden)

    Mohammed F. Hamza

    2017-05-01

    Full Text Available A new magnetic functionalized derivative of chitosan is synthesized and characterized for the sorption of metal ions (environmental applications and metal valorization. The chemical modification of the glycine derivative of chitosan consists of: activation of the magnetic support with epichlorohydrin, followed by reaction with either glycine to produce the reference material (i.e., Gly sorbent or glycine ester hydrochloride, followed by hydrazinolysis to synthesize the hydrazide functionalized sorbent (i.e., HGly sorbent. The materials are characterized by titration, elemental analysis, FTIR analysis (Fourrier-transform infrared spectrometry, TGA analysis (thermogravimetric analysis and with SEM-EDX (scanning electron microscopy coupled to energy dispersive X-ray analysis. The sorption performances for U(VI, Cu(II, and Zn(II are tested in batch systems. The sorption performances are compared for Gly and HGly taking into account the effect of pH, the uptake kinetics (fitted by the pseudo-second order rate equation, and the sorption isotherms (described by the Langmuir and the Sips equations. The sorption capacities of the modified sorbent reach up to 1.14 mmol U g−1, 1.69 mmol Cu g−1, and 0.85 mmol Zn g−1. In multi-metal solutions of equimolar concentration, the chemical modification changes the preferences for given metal ions. Metal ions are desorbed using 0.2 M HCl solutions and the sorbents are re-used for five cycles of sorption/desorption without significant loss in performances.

  20. Existence or absence of bandgap bowing in II-VI ternary alloys: Comparison between common-anion and common-cation cases

    Science.gov (United States)

    Tit, Nacir; Obaidat, I. M.; Reshak, A. H.; Alawadhi, H.

    2010-02-01

    The common-anion and common-cation II-VI ternary alloys of the family Cd(Zn)Se(Te) are theoretically investigated based on two different methods. Within the virtual-crystal approximation (VCA), both the sp3s*-tight-binding method, with the inclusion of spin-orbit coupling, and the first-principle full-potential linear augmented plane waves (FP-LAPW) technique are employed to determine the alloy constituents' charge states (ionicities) and degree of bond polarity. The results show that: (i) in the common-cation ternary alloys (i.e., CdSexTe1-x and ZnSexTe1-x), the anions alter a strong competition in trapping more charge. Such a competition builds up a compromised effect yielding the bowing behaviour. Whereas, (ii) in the common-anion ternary alloys (i.e., CdyZn1-yTe and CdyZn1-ySe), the absence of such competition would cause the complete absence of bandgap bowing behaviour. The variation of the bandgap is found to be rather close to linear. The obtained good agreement between our theoretical results and the recently available photoluminescence data does further corroborate our claims.

  1. Burkholderia cenocepacia type VI secretion system mediates escape of type II secreted proteins into the cytoplasm of infected macrophages.

    Directory of Open Access Journals (Sweden)

    Roberto Rosales-Reyes

    Full Text Available Burkholderia cenocepacia is an opportunistic pathogen that survives intracellularly in macrophages and causes serious respiratory infections in patients with cystic fibrosis. We have previously shown that bacterial survival occurs in bacteria-containing membrane vacuoles (BcCVs resembling arrested autophagosomes. Intracellular bacteria stimulate IL-1β secretion in a caspase-1-dependent manner and induce dramatic changes to the actin cytoskeleton and the assembly of the NADPH oxidase complex onto the BcCV membrane. A Type 6 secretion system (T6SS is required for these phenotypes but surprisingly it is not required for the maturation arrest of the BcCV. Here, we show that macrophages infected with B. cenocepacia employ the NLRP3 inflammasome to induce IL-1β secretion and pyroptosis. Moreover, IL-1β secretion by B. cenocepacia-infected macrophages is suppressed in deletion mutants unable to produce functional Type VI, Type IV, and Type 2 secretion systems (SS. We provide evidence that the T6SS mediates the disruption of the BcCV membrane, which allows the escape of proteins secreted by the T2SS into the macrophage cytoplasm. This was demonstrated by the activity of fusion derivatives of the T2SS-secreted metalloproteases ZmpA and ZmpB with adenylcyclase. Supporting this notion, ZmpA and ZmpB are required for efficient IL-1β secretion in a T6SS dependent manner. ZmpA and ZmpB are also required for the maturation arrest of the BcCVs and bacterial intra-macrophage survival in a T6SS-independent fashion. Our results uncover a novel mechanism for inflammasome activation that involves cooperation between two bacterial secretory pathways, and an unanticipated role for T2SS-secreted proteins in intracellular bacterial survival.

  2. An Examination of the Validity of the Family Affluence Scale II (FAS II) in a General Adolescent Population of Canada

    Science.gov (United States)

    Boudreau, Brock; Poulin, Christiane

    2009-01-01

    This study examined the performance of the FAS II in a general population of 17,545 students in grades 7, 9, 10 and 12 in the Atlantic provinces of Canada. The FAS II was assessed against two other measures of socioeconomic status: mother's highest level of education and family structure. Our study found that the FAS II reduces the likelihood of…

  3. Estimated dietary intake and major food sources of polyphenols in elderly of Viçosa, Brazil: a population-based study.

    Science.gov (United States)

    Nascimento-Souza, Mary Anne; de Paiva, Pedro Gontijo; Pérez-Jiménez, Jara; do Carmo Castro Franceschini, Sylvia; Ribeiro, Andréia Queiroz

    2016-11-21

    Epidemiological studies have remarked the beneficial role that polyphenols may have in the elderly population such as cancer and cardiovascular disease prevention. This is particularly relevant considering the global tendency of population aging. Data on polyphenol intake in the elderly population are scarce and usually provide partial information-only for some polyphenol classes. The aim of this study was to estimate the intake of polyphenols and its major dietary contributors in the population of Viçosa. A cross-sectional population-based survey including 620 elderly was conducted in Viçosa, Brazil. Food intake was estimated by recall of habitual consumption (RHC). Polyphenol intake was calculated by matching food consumption data from the RHC with the polyphenol content in foods listed in the Phenol-Explorer database. The average total polyphenol intake was 1198.6 mg/day (533.7 mg/day as aglycone). The main polyphenol classes were phenolic acids (729.5 mg/day) and flavonoids (444.7 mg/day). The main dietary contributors for total polyphenols were coffee (45.8%), beans (32.8%) and polenta (1.3%). A total of 292 polyphenols divided in 14 classes and 23 subclasses were found. The individual compounds with the highest intake were isomers of chlorogenic acid (i.e., 5-caffeoylquinic acid, 4-caffeoylquinic acid and 3-caffeoylquinic acid) among hydroxycinnamic acids that largely originated from coffee. The data reported here can be used to evaluate the association between the amount and type of ingested polyphenols and health outcomes in epidemiological studies in order to eventually establish nutritional recommendations.

  4. María Zambrano: Obras completas, vol. I, II, III y VI, Galaxia Gutenberg, 2011-2016

    OpenAIRE

    Trapanese, Elena

    2017-01-01

    Reseñas de: I (Libros 1930-1939), edición dirigida por Jesús Moreno Sanz con la colaboración de Pedro Chacón Fuertes, Mercedes Gómez Blesa, Mariano Rodríguez González y Antolín Sánchez Cuervo, Barcelona, Galaxia Gutenberg, 2015 [Reúne los libros: Horizonte del liberalismo, Los intelectuales en el drama de España, Pensamiento y poesía en la vida española, Filosofía y poesía.]. Obras Completas. II (Libros 1939-1950), edición dirigida por Jesús Moreno Sanz con la colaboración d...

  5. Removal of As(V, Cr(VI and Pb(II from aqueous solution using surfactant-modified Sabzevar nanozeolite

    Directory of Open Access Journals (Sweden)

    Kourosh Razmgar

    2016-04-01

    Full Text Available The pollution of water environments is a challenging issue especially in developing countries. Contamination of drinking water with heavy metals has been reported in many parts of the world. Arsenic, chromium and lead are dangerous heavy metals and also common contaminants of drinking water. In this study, the capacity and performance of the surfactant-modified Sabzevar natural nanozeolite (SMSNZ on the removal of heavy metals from an aqueous solution was investigated. Initially, the appropriate concentration of hexadecyltrimethylammonium bromide HDTMA-Br solution for modification was investigated; it was found that it must be higher than the critical concentration micelle (CMC. Then, the removal of As (V, Cr (VI, and Pb(II from an aqueous solution was studied using SMSNZ. The results indicated that the removal efficiency was very high in different initial concentrations of heavy metals. The Linear, Langmuir and Freundlich isotherm models were used to investigate the adsorption equilibrium of the surfactant-modified natural zeolite for heavy metals adsorption. The results showed that the Linear isotherm is a better fit for the three studied heavy metals.

  6. Synthesis, structural characterization and antioxidant activity of some vanadium(IV), Mo(VI)/(IV) and Ru(II) complexes of pyridoxal Schiff base derivatives

    Science.gov (United States)

    Elsayed, Shadia A.; Noufal, Aya M.; El-Hendawy, Ahmed M.

    2017-09-01

    New complexes containing vanadium(IV), Mo(VI)/(IV) and Ru(II) derived from Schiff base of pyridoxal and S-benzyldithiocarbazate (H2pysb) or p-toluidine (Hpytol) have been prepared. The structures of the described compounds were elucidated by elemental analyses, spectroscopic techniques (IR, 1H NMR, UV-Vis and EPR) magnetism, molar conductivity and thermal analysis measurements. Their redox behaviors were also studied by cyclic voltammetry. The ligand H2pysb showed coordination to the metal ions in a dibasic tridenate manner through deprotonated phenolate oxygen, azomethine nitrogen and thiolate sulfur, while Hpytol behaved as monobasic bidentate through phenolate oxygen and azomethine nitrogen. The complexes were tested for their antioxidant activity by 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and the data obtained revealed that the scavenging activity of the complexes towards DPPH is high for the oxovanadium(IV) complexes with lower IC50 values which are comparable to ascorbic acid as a standard antioxidant. The EC50 concentration ratio together with other antioxidant parameters are also reported.

  7. Estudio del equilibrio y cinética de adsorción de Cd(II, Ni(II y Cr(VI usando Quitosano y Quitosano modificado con cobre

    Directory of Open Access Journals (Sweden)

    M. Benavente

    2013-04-01

    Full Text Available En este trabajo, se estudió el equilibrio y la cinética de adsorción de Cd(II, Ni(II en quitosano y Cr(VI en quitosano modificado con cobre. Para ello, soluciones de iones metálicos a diferentes concentraciones, fueron puestas en contacto con el adsorbente y se agitaron por un período de 3 – 4 h. Al final del proceso, las muestras fueron analizadas en un espectrómetro de absorción atómica. Los datos experimentales del equilibrio de adsorción de los iones metálicos fueron evaluados aplicando las isotermas de Langmuir y Freundlich; mientras los datos cinéticos fueron evaluados utilizando los modelos cinéticos de pseudo-primer orden y pseudo-segundo orden. Los resultados del proceso demostraron que los iones fueron eficazmente adsorbidos por el quitosano (Cd y Ni y por el Cu-quitosano (Cr. Además, se comprobó que los datos experimentales del equilibrio de adsorción de Cr(VI y Ni(II se ajustan al modelo de Langmuir; mientras que los datos experimentales del Cd(II fueron mejor ajustados por el modelo de Freundlich. Mediante el uso de la isoterma de Langmuir se determinó la capacidad máxima de adsorción de cromo (29.7 mg/g Cu-quitosano, cadmio (102.0 mg/g quitosano y níquel (83.31 mg/g quitosano. Los resultados de la cinética de adsorción de los iones metálicos mostraron que los datos experimentales fueron mejor ajustados por el modelo de pseudo-segundo orden; es decir, el paso limitante en la velocidad es la reacción de adsorción y no la transferencia de masa.

  8. Validating the Beck Depression Inventory-II in Indonesia's general population and coronary heart disease patients

    NARCIS (Netherlands)

    Ginting, H.; Näring, G.W.B.; Veld, W.M. van der; Srisayekti, W.; Becker, E.S.

    2013-01-01

    This study assesses the validity and determines the cut-off point for the Beck Depression Inventory-II (the BDI-II) among Indonesians. The Indonesian version of the BDI-II (the Indo BDI-II) was administered to 720 healthy individuals from the general population, 215 Coronary Heart Disease (CHD)

  9. Mucopolysaccharidosis VI

    Science.gov (United States)

    2010-01-01

    Mucopolysaccharidosis VI (MPS VI) is a lysosomal storage disease with progressive multisystem involvement, associated with a deficiency of arylsulfatase B leading to the accumulation of dermatan sulfate. Birth prevalence is between 1 in 43,261 and 1 in 1,505,160 live births. The disorder shows a wide spectrum of symptoms from slowly to rapidly progressing forms. The characteristic skeletal dysplasia includes short stature, dysostosis multiplex and degenerative joint disease. Rapidly progressing forms may have onset from birth, elevated urinary glycosaminoglycans (generally >100 μg/mg creatinine), severe dysostosis multiplex, short stature, and death before the 2nd or 3rd decades. A more slowly progressing form has been described as having later onset, mildly elevated glycosaminoglycans (generally sialidosis and mucolipidosis. Before enzyme replacement therapy (ERT) with galsulfase (Naglazyme®), clinical management was limited to supportive care and hematopoietic stem cell transplantation. Galsulfase is now widely available and is a specific therapy providing improved endurance with an acceptable safety profile. Prognosis is variable depending on the age of onset, rate of disease progression, age at initiation of ERT and on the quality of the medical care provided. PMID:20385007

  10. Mucopolysaccharidosis VI

    Directory of Open Access Journals (Sweden)

    Harmatz Paul

    2010-04-01

    Full Text Available Abstract Mucopolysaccharidosis VI (MPS VI is a lysosomal storage disease with progressive multisystem involvement, associated with a deficiency of arylsulfatase B leading to the accumulation of dermatan sulfate. Birth prevalence is between 1 in 43,261 and 1 in 1,505,160 live births. The disorder shows a wide spectrum of symptoms from slowly to rapidly progressing forms. The characteristic skeletal dysplasia includes short stature, dysostosis multiplex and degenerative joint disease. Rapidly progressing forms may have onset from birth, elevated urinary glycosaminoglycans (generally >100 μg/mg creatinine, severe dysostosis multiplex, short stature, and death before the 2nd or 3rd decades. A more slowly progressing form has been described as having later onset, mildly elevated glycosaminoglycans (generally ARSB gene, located in chromosome 5 (5q13-5q14. Over 130 ARSB mutations have been reported, causing absent or reduced arylsulfatase B (N-acetylgalactosamine 4-sulfatase activity and interrupted dermatan sulfate and chondroitin sulfate degradation. Diagnosis generally requires evidence of clinical phenotype, arylsulfatase B enzyme activity ®, clinical management was limited to supportive care and hematopoietic stem cell transplantation. Galsulfase is now widely available and is a specific therapy providing improved endurance with an acceptable safety profile. Prognosis is variable depending on the age of onset, rate of disease progression, age at initiation of ERT and on the quality of the medical care provided.

  11. Galactic bulge population II Cepheids in the VVV survey: period-luminosity relations and a distance to the Galactic centre

    Science.gov (United States)

    Bhardwaj, A.; Rejkuba, M.; Minniti, D.; Surot, F.; Valenti, E.; Zoccali, M.; Gonzalez, O. A.; Romaniello, M.; Kanbur, S. M.; Singh, H. P.

    2017-09-01

    Context. Multiple stellar populations of different ages and metallicities reside in the Galactic bulge that trace its structure and provide clues to its formation and evolution. Aims: We present the near-infrared observations of population II Cepheids in the Galactic bulge from VISTA Variables in the Vía Láctea (VVV) survey. The JHKs photometry together with optical data from Optical Gravitational Lensing Experiment (OGLE) survey provide an independent estimate of the distance to the Galactic centre. The old, metal-poor and low-mass population II Cepheids are also investigated as useful tracers for the structure of the Galactic bulge. Methods: We identify 340 population II Cepheids in the VVV survey Galactic bulge catalogue based on their match with the OGLE-III Catalogue. The single-epoch JH and multi-epoch Ks observations complement the accurate periods and optical (VI) mean-magnitudes from OGLE. The sample consisting of BL Herculis and W Virginis subtypes is used to derive period-luminosity relations after correcting mean-magnitudes for the extinction. Our Ks-band period-luminosity relation, Ks = -2.189(0.056) [log (P)-1] + 11.187(0.032), is consistent with published work for BL Herculis and W Virginis variables in the Large Magellanic Cloud. Results: We present a combined OGLE-III and VVV catalogue with periods, classification, mean magnitudes, and extinction for 264 Galactic bulge population II Cepheids that have good-quality Ks-band light curves. The absolute magnitudes for population II Cepheids and RR Lyraes calibrated using Gaia and Hubble Space Telescope parallaxes, together with calibrated magnitudes for Large Magellanic Cloud population II Cepheids, are used to obtain a distance to the Galactic centre, R0 = 8.34 ± 0.03(stat.) ± 0.41(syst.), which changes by with different extinction laws. While noting the limitation of small number statistics, we find that the present sample of population II Cepheids in the Galactic bulge shows a nearly spheroidal

  12. Mécanismes de formation des boîtes quantiques semiconductrices, application aux nanostructures II-VI et étude de leurs propriétés optiques

    OpenAIRE

    TINJOD, Frank

    2003-01-01

    Président : Philippe LAVALLARD Rapporteurs : Catherine PRIESTER Olivier THOMAS Examinateur : Jacek K. FURDYNA Codirecteur de thèse : Kuntheak KHENG Directeur de thèse : Henri MARIETTE; Semiconductor quantum dot formation mechanisms, application to II-VI nanostructures(quantum wells and dots) and study of their optical properties This work presents a model for heteroepitaxial growth at equilibrium which shows the main parameters that govern strain relaxation in thin films. The effective growth...

  13. Influence of both the composition of impregnation solution and impregnation method on copper(II, chromium(VI and silver(I deposition on activated carbon

    Directory of Open Access Journals (Sweden)

    Ivanović Slavica

    2003-01-01

    Full Text Available The composition of a solution for impregnating activated carbon (AC for use in a gas filter was investigated. The solution components were tetraaminocop-per(II complex, chromium(VI, silver(l and carbonate ions. Two methods of impregnation were investigated: ion adsorption from aqueous solution in excess and the incipient wetness method. Copper, chromium and silver con-tents on AC Were determined by atomic absorption spectrometry. The largest copper contents (4.38 and 5.00 % (w/w for two AC samples were achieved at: c([Cu(NH34]2+ = 1.0 mol/L; M(Cu i M(Cr = 3.75: 1; M(Cu i M(Ag = 62: 1 and M(Cu: M(CO3 = 2: 1, using two fold impregnation by the incipient wetness method with 2.4 mL of solution per 3 g AC. The contents of chromium and silver on the same AC samples Were 1.06 and 0.0098 % for the first and 1.14 and 0.009 % for the second AC. A larger Cr content (1.57 % was achieved from an impregnation solution in excess (c([Cu(NH34]2+ = 1.25 mol/L; M(Cu i M(Cr = 3: 1; without Ag. The largest Ag content (0.17 % was obtained using two fold impregnation by the incipient wetness method (c([Cu(NH34]2+ = 0.8 mol/L; M(Cu: M(Cr = 3.75: 1<; M(Cu i M(Ag ( 80: 1 and M(Cu i M(CO3 = 1 i 1.32. Larger metal contents were obtained using two fold impregnation by the incipient wetness method. Further work is needed on the determination of the influence of carbonate ions both on the solution stability and metal deposition on AC.

  14. Terapia de reposição enzimática para as mucopolissacaridoses I, II e VI: recomendações de um grupo de especialistas brasileiros Enzyme replacement therapy for mucopolysaccharidoses I, II and VI: recommendations from a group of Brazilian F experts

    Directory of Open Access Journals (Sweden)

    Roberto Giugliani

    2010-01-01

    Full Text Available As mucopolissacaridoses (MPS são doenças genéticas raras causadas pela deficiência de enzimas lisossômicas específicas que afetam o catabolismo de glicosaminoglicanos (GAG. O acúmulo de GAG em vários órgãos e tecidos nos pacientes afetados pelas MPS resulta em uma série de sinais e sintomas, integrantes de um quadro clínico multissistêmico que compromete ossos e articulações, vias respiratórias, sistema cardiovascular e muitos outros órgãos e tecidos, incluindo, em alguns casos, as funções cognitivas. Já foram identificados 11 defeitos enzimáticos que causam sete tipos diferentes de MPS. Antes do advento de terapias dirigidas para a restauração da atividade da enzima deficiente, o tratamento das MPS tinha como principal foco a prevenção e o cuidado das complicações, aspecto ainda bastante importante no manejo desses pacientes. Na década de 80 foi proposto o tratamento das MPS com transplante de medula óssea/transplante de células tronco hematopoiéticas (TMO/TCTH e na década de 90 começou o desenvolvimento da Terapia de Reposição Enzimática (TRE, que se tornou uma realidade aprovada para uso clínico nas MPS I, II e VI na primeira década do século 21. Os autores deste trabalho têm a convicção de que um melhor futuro para os pacientes afetados pelas MPS depende da identificação, compreensão e manejo adequado das manifestações multissistêmicas dessas doenças, incluindo medidas de suporte (que devem fazer parte da assistência multidisciplinar regular destes pacientes e terapias específicas. Embora a inibição da síntese de GAG e o resgate da atividade enzimática com moléculas pequenas também possam vir a ter um papel no manejo das MPS, o grande avanço disponível no momento é a TRE intravenosa. A TRE permitiu modificar radicalmente o panorama do tratamento das mucopolissacaridoses I, II e VI na última década, sendo que ainda pode estender seus benefícios em breve para a MPS IV A (cuja TRE

  15. National Aggregates of Geospatial Data Collection: Population, Landscape, And Climate Estimates, Version 2 (PLACE II)

    Data.gov (United States)

    National Aeronautics and Space Administration — The Population, Landscape, And Climate Estimates, Version 2 (PLACE II) dataset contains estimates of national-level aggregations of territorial extent and population...

  16. Trypanosoma cruzi Discret Typing Units (TcII and TcVI) in samples of patients from two municipalities of the Jequitinhonha Valley, MG, Brazil, using two molecular typing strategies.

    Science.gov (United States)

    de Oliveira, Maykon Tavares; de Assis, Girley Francisco Machado; Oliveira e Silva, Jaquelline Carla Valamiel; Machado, Evandro Marques Menezes; da Silva, Glenda Nicioli; Veloso, Vanja Maria; Macedo, Andrea Mara; Martins, Helen Rodrigues; de Lana, Marta

    2015-10-31

    Trypanosoma cruzi is classified into six discrete taxonomic units (DTUs). For this classification, different biological markers and classification criteria have been used. The objective was to identify the genetic profile of T. cruzi samples isolated from patients of two municipalities of Jequitinhonha Valley, MG, Brazil. Molecular characterization was performed using two different criteria for T. cruzi typing to characterize 63 T. cruzi samples isolated from chronic Chagas disease patients. The characterizations followed two distinct methodologies. Additionally, the RAPD technique was used to evaluate the existence of genetic intragroup variability. The first methodology identified 89% of the samples as TcII, but it was not possible to define the genetic identity of seven isolates. The results obtained with the second methodology corroborated the classification as TcII of the same samples and defined the classification of the other seven as TcVI. RAPD analysis showed lower intra-group variability in TcII. The results confirmed the preliminary data obtained in other municipalities of the Jequitinhonha Valley, showing a predominance of TcII, similar to that verified in northeast/south axis of Brazil and the first detection of TcVI in the study region. The second protocol was more simple and reliable to identify samples of hybrid character.

  17. TcI, TcII and TcVI Trypanosoma cruzi samples from Chagas disease patients with distinct clinical forms and critical analysis of in vitro and in vivo behavior, response to treatment and infection evolution in murine model.

    Science.gov (United States)

    Oliveira, Maykon Tavares de; Branquinho, Renata Tupinambá; Alessio, Gláucia Diniz; Mello, Carlos Geraldo Campos; Nogueira-de-Paiva, Nívia Carolina; Carneiro, Cláudia Martins; Toledo, Max Jean de Ornelas; Reis, Alexandre Barbosa; Martins-Filho, Olindo Assis Martins; Lana, Marta de

    2017-03-01

    The clonal evolution of Trypanosoma cruzi sustains scientifically the hypothesis of association between parasite's genetic, biological behavior and possibly the clinical aspects of Chagas disease in patients from whom they were isolated. This study intended to characterize a range of biological properties of TcI, TcII and TcVI T. cruzi samples in order to verify the existence of these associations. Several biological features were evaluated, including in vitro epimastigote-growth, "Vero"cells infectivity and growth, along with in vivo studies of parasitemia, polymorphism of trypomastigotes, cardiac inflammation, fibrosis and response to treatment by nifurtimox during the acute and chronic murine infection. The global results showed that the in vitro essays (acellular and cellular cultures) TcII parasites showed higher values for all parameters (growth and infectivity) than TcVI, followed by TcI. In vivo TcII parasites were more virulent and originated from patients with severe disease. Two TcII isolates from patients with severe pathology were virulent in mice, while the isolate from a patient with the indeterminate form of the disease caused mild infection. The only TcVI sample, which displayed low values in all parameters evaluated, was also originated of an indeterminate case of Chagas disease. Response to nifurtimox was not associated to parasite genetic and biology, as well as to clinical aspects of human disease. Although few number of T. cruzi samples have been analyzed, a discreet correlation between parasite genetics, biological behavior in vitro and in vivo (murine model) and the clinical form of human disease from whom the samples were isolated was verified. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Knowledge attitudes and practice toward epilepsy among adults in BaVi, Vietnam: first report from the population-based EPIBAVI study.

    Science.gov (United States)

    Tuan, Nguyen Anh; Cuong, Le Quang; Allebeck, Peter; Chuc, Nguyen Thi Kim; Tomson, Torbjorn

    2007-10-01

    We conducted a survey to assess knowledge, attitudes, and practice toward epilepsy in a population-based study in a rural district of Vietnam. We utilized an established knowledge-attitudes-practice questionnaire. This was applied by trained surveyors in face-to-face interviews of 2005 randomly selected adult residents (19-71 years of age) of the BaVi district, 60 km west of Hanoi. Of the respondents, 67.0% had heard about epilepsy, 52.1% had known someone with seizures, and 49.3% had witnessed seizures. In total, 36.3% would object to their children playing with someone with seizures and 82.0% to their children marrying someone with epilepsy. Only 32.6% thought that epilepsy patients should be employed in a job as other people, while 10% thought that epilepsy was a form of insanity. Familiarity with epilepsy, having heard of epilepsy, known someone with epilepsy, or having seen seizures was associated with less negative attitudes. About half of the respondents (50.4%) thought epilepsy was caused by a brain disease and 80.1% would suggest consultation of a medical doctor for epilepsy. Knowledge of epilepsy among Vietnamese people is still limited compared to some Western countries and the attitudes more negative. Our findings indicated more negative attitudes than in another recent survey from Vietnam. This may be due to differences in sociodemographic characteristics and educational level of the study populations. The discrepancies demonstrate the importance of selection of study population and the need for caution in generalizing from results of surveys.

  19. Immunohistochemical localization of collagenous components in healthy periodontal tissues of the rat and marmoset (Callithrix jacchus). II. Distribution of collagen types IV, V and VI.

    Science.gov (United States)

    Romanos, G E; Schröter-Kermani, C; Hinz, N; Wachtel, H C; Bernimoulin, J P

    1991-07-01

    The immunohistochemical distribution of collagen types IV, V and VI has been demonstrated in healthy periodontal tissues of rats and marmosets following decalcification of the maxillae and mandibulae in 0.2 N HCl. An intense fluorescence with anti-collagen type IV antibodies was demonstrated in the basement membranes of the epithelium and of the blood vessels and nerves. In the alveolar bone stroma and in the periodontal ligament (PL) collagen type IV was present only in the basal membranes of the blood vessels and nerves. In comparison, collagen type V was observed in a fibrillar pattern in the gingival connective tissue, as well as the PL. In the PL, type V collagenous fibers demonstrated a parallel distribution with stronger fluorescence near the cementum surface. Collagen type VI could be demonstrated in fine fibers present in the gingival connective tissue and the PL. Blood vessels and nerves were not stained in the marmoset, but were in the rat, where a localization of collagen type VI was demonstrated in these areas. Alveolar bone and cementum, as well as the Sharpey's fibers embedded in these tissues, were not stained with antibodies against collagen type V and type VI, but a pericellular localization of these collagenous components could be observed. Collectively, these results provide basic information on the relative distribution of different collagen types in normal tissues of rats and marmosets that will be required for future studies on the effects of pathological, reparative and regenerative processes.

  20. Structural, spectral analysis and DNA studies of heterocyclic thiosemicarbazone ligand and its Cr(III), Fe(III), Co(II) Hg(II), and U(VI) complexes

    Science.gov (United States)

    Yousef, T. A.; Abu El-Reash, G. M.; El Morshedy, R. M.

    2013-08-01

    The paper presents a combined experimental and computational study of novel Cr(III), Fe(III), Co(II), Hg(II) and U(VI) complexes of (E)-2-((3-hydroxynaphthalen-2-yl)methylene)-N-(pyridin-2-yl)hydrazinecarbothioamide (H2L). The ligand and its complexes have been characterized by elemental analyses, spectral (IR, UV-vis, 1H NMR and 13C NMR), magnetic and thermal studies. IR spectra show that H2L is coordinated to the metal ions in a mononegative bi or tri manner. The structures are suggested to be octahedral for all complexes except Hg(II) complex is tetrahedral. Theoretical calculations have been performed to obtain IR spectra of ligand and its complexes using AM1, MM, Zindo/1, MM+ and PM3, methods. Satisfactory theoretical-experimental agreements were achieved by MM method for the ligand and PM3 for its complexes. DOS calculations carried out by MM (ADF) method for ligand Hg complex from which we concluded that the thiol form of the ligand is more active than thione form and this explains that the most complexation take place in that form. The calculated IR vibrations of the metal complexes, using the PM3 method was the nearest method for the experimental data, and it could be used for all complexes. Also, valuable information are obtained from calculation of molecular parameters for all compounds carried out by the previous methods of calculation (electronegativity of the coordination sites, net dipole moment of the metal complexes, values of heat of formation and binding energy) which approved that the complexes are more stable than ligand. The low value of ΔE could be expected to indicate H2L molecule has high inclination to bind with the metal ions. Furthermore, the kinetic and thermodynamic parameters for the different decomposition steps were calculated using the Coats-Redfern and Horowitz-Metzger methods. Finally, the biochemical studies showed that, complex 2, 4 have powerful and complete degradation effect on DNA. For the foremost majority of cases the

  1. Cranial mononeuropathy VI

    Science.gov (United States)

    ... Abducens palsy; Lateral rectus palsy; VIth nerve palsy; Cranial nerve VI palsy; Sixth nerve palsy; Neuropathy - sixth nerve ... Cranial mononeuropathy VI is damage to the sixth cranial nerve. This nerve is also called the abducens nerve. ...

  2. Bis(tetraphenylphosphonium) (hexasulfido-2kappa2S1,S6)di-mu-sulfido-disulfido-1kappa2S-tungsten(VI)zinc(II) acetone solvate.

    Science.gov (United States)

    Beheshti, Azizolla; Clegg, William; Dale, Sophie H; Hyvadi, Reza

    2009-09-01

    The title complex, (C(24)H(20)P)(2)[WZnS(4)(S(6))].C(3)H(6)O or (Ph(4)P)(2)[WS(2)(mu-S)(2){Zn(S(6))}].Me(2)CO, was unexpectedly obtained on attempted recrystallization of a mixed tungten-zinc complex of a tris(pyrazolato)borate ligand. The two metal centres of the anion have distorted tetrahedral coordination and the two tetrahedra share one S...S edge; tungsten is additionally coordinated by two terminal sulfide ligands and zinc by a chelating S(6)(2-) ligand, which has one central S-S bond significantly longer than the other four, a pattern found to be consistent for this ligand. This is the first reported example of a tetrahedral zinc centre bridging an edge of a single tetrathiotungstate(VI) or tetrathiomolybdate(VI) anion, although there are many previous examples with other metals.

  3. X-ray diffraction study of epitaxial heterostructures of II-VI CdTe and ZnTe semiconductors; Etude par diffraction de rayons X d`heterostructures epitaxiees a base des semi-conducteurs II-VI CdTe et ZnTe

    Energy Technology Data Exchange (ETDEWEB)

    Bouchet-Boudet, N.

    1996-10-07

    This work deals with the structural study of II-VI semiconductor (CdTe and ZnTe) heterostructures by X-ray diffraction and reflectivity. These heterostructures have a high lattice parameter misfit and are grown by Molecular Beam Epitaxy. Two main subjects are developed: the characterization of ZnTe wires, grown by step propagation on a CdTe (001) vicinal surface, and the study of the vertical correlations in Cd{sub 0.8}Zn{sub 0.2}Te / CdTe superlattices and superlattices made of ZnTe fractional layers spaced by CdTe. The growth of organised system is up to date; its aim is to realize quantum boxes (or wires) superlattices which are laterally and vertically ordered. The deformation along the growth axis induced by a ZnTe fractional layer inserted in a CdTe matrix is modelled, in the kinematical approximation, to reproduce the reflectivity measured around the substrate (004) Bragg peak. The lateral periodicity of the wires, deposited on a vicinal surface is a new and difficult subject. Some results are obtained on a vertical superlattice grown on a 1 deg. mis-cut surface. The in-plane and out-of-plane correlation lengths of a Cd{sub 0.8}Zn{sub 0.2}Te / CdTe superlattice are deduced from the diffused scattered intensity measured at grazing incidence. The calculations are made within the `distorted Wave Born Approximation`. The vertical correlation in ZnTe boxes (or wines) superlattices can be measured around Bragg peaks. It is twice bigger in a superlattice grown on a 2 deg. mis-cut substrate than a nominal one. (author). 74 refs.

  4. Population Changes in a Community of Alkaliphilic Iron-Reducing Bacteria Due to Changes in the Electron Acceptor: Implications for Bioremediation at Alkaline Cr(VI)-Contaminated Sites.

    Science.gov (United States)

    Fuller, Samuel J; Burke, Ian T; McMillan, Duncan G G; Ding, Weixuan; Stewart, Douglas I

    A serial enrichment culture has been grown in an alkaline Fe(III)-citrate-containing medium from an initial inoculum from a soil layer beneath a chromium ore processing residue (COPR) disposal site where Cr(III) is accumulating from Cr(VI) containing leachate. This culture is dominated by two bacterial genera in the order Clostridiales, Tissierella, and an unnamed Clostridium XI subgroup. This paper investigates the growth characteristics of the culture when Cr(VI) is added to the growth medium and when aquifer sand is substituted for Fe(III)-citrate. The aim is to determine how the availability and chemical form of Fe(III) affects the growth of the bacterial consortium, to determine the impact of Cr(VI) on growth, and thus attempt to understand the factors that are controlling Cr(III) accumulation beneath the COPR site. The culture can grow fermentatively at pH 9.2, but growth is stronger when it is associated with Fe(III) reduction. It can withstand Cr(VI) in the medium, but growth only occurs once Cr(VI) is removed from solution. Cr(VI) reduced the abundance of Tissierella sp. in the culture, whereas the Clostridium XI sp. was Cr(VI) tolerant. In contrast, growth with solid phase Fe(III)-oxyhydroxides (present as coatings on aquifer sand) favoured the Tissierella C sp., possibly because it produces riboflavin as an extracellular electron shuttling compound allowing more efficient electron transfer to solid Fe(III) phases. Thus, it is suggested that bacterially mediated Cr(III) reduction in the soil beneath the COPR site is dependent on Fe(III) reduction to sustain the bacterial community.

  5. Prognostic importance of VEGF-A haplotype combinations in a stage II colon cancer population

    DEFF Research Database (Denmark)

    Kjaer-Frifeldt, Sanne; Fredslund, Rikke; Lindebjerg, Jan

    2012-01-01

    To investigate the prognostic effect of three VEGF-A SNPs, -2578, -460 and 405, as well as the corresponding haplotype combinations, in a unique population of stage II colon cancer patients.......To investigate the prognostic effect of three VEGF-A SNPs, -2578, -460 and 405, as well as the corresponding haplotype combinations, in a unique population of stage II colon cancer patients....

  6. Derfor elsker og hader vi positiv psykologi

    DEFF Research Database (Denmark)

    Mehlsen, Camilla

    2010-01-01

    Hvorfor er positiv psykologi så populært? Er positiv psykologi ved at blive en religion? Asterisk har mødt tre fremtrædende forskere, der forklarer, hvorfor vi elsker og hader positiv psykolog.......Hvorfor er positiv psykologi så populært? Er positiv psykologi ved at blive en religion? Asterisk har mødt tre fremtrædende forskere, der forklarer, hvorfor vi elsker og hader positiv psykolog....

  7. 94 STUDIES ON DOG POPULATION IN MAKURDI, NIGERIA (II): A ...

    African Journals Online (AJOL)

    This study investigated the current status of dog infestation by ectoparasites, compared infestation between stray and restricted dogs and ... Key words: Ectoparasites infestation, Dogs, Zoonotic implications, Prevalence, Makurdi. INTRODUCTION ..... human association with large pig population that roamed freely in the area.

  8. Griffonia simplicifolia II lectin labels a population of radial glial cells in the embryonic rat brain.

    Science.gov (United States)

    Hurley, S D; Streit, W J

    1995-01-01

    Staining with the Griffonia simplicifolia II lectin (GSL II), a marker for adult rat oligodendrocytes, was studied in rat brain at embryonic (E) days E14, E16, E18, and E20. At E14, only two regions of the CNS showed labeling--the hippocampal primordium and the ventromedial floor of the mesencephalic aqueduct and fourth ventricle. Labeling in these areas was confined to cells with bipolar processes which spanned from the ventricular lumen to the pial surface. At E16, GSL II+ radial glia were present in the hippocampus, septal area, cerebral peduncle, thalamus, tegmentum, and throughout much of the midbrain. At E16, E18, and E20, GSL II strongly labeled two midline radial glial raphes--dorsal to the mesencephalic aqueduct and ventral to the mesencephalic aqueduct and fourth ventricle. Comparison of GSL II lectin labeling with nestin immunostaining, using Rat-401, showed that GSL II labeled a distinct population of radial cells different from nestin-positive radial glia. GSL II also labeled a group of neurons at E16 and E18 in the hypothalamus and basal striatum. We suggest that GSL II+ radial glia represent a population of oligodendroglial precursors present in the embryonic brain, and that GSL II reactivity could serve as a differentiation marker for cells committed to the oligodendroglial lineage. This work supports the possibility that some oligodendroglia, like astrocytes, are derived from radial glial precursors.

  9. Linkage and association of HLA class II genes with vitiligo in a Dutch population

    NARCIS (Netherlands)

    Zamani, M.; Spaepen, M.; Sghar, S. S.; Huang, C.; Westerhof, W.; Nieuweboer-Krobotova, L.; Cassiman, J. J.

    2001-01-01

    Serological typing of HLA has shown discrepancies in HLA associations with vitiligo in different ethnic populations. To perform genotyping of HLA class II genes on a Dutch vitiligo population in order clearly to identify susceptible and protective HLA alleles in vitiligo. HLA typing was carried out

  10. Parameter estimation for multiple weibull populations under joint type-II censoring

    OpenAIRE

    Samir Ashour; Osama Eraki

    2014-01-01

    In this paper, we introduce the maximum likelihood estimation for k Weibull populations under joint type II censored scheme and different special cases have been obtained.  The asymptotic variance covariance matrix and approximate confidence region based on the asymptotic normality of the maximum likelihood estimators have been obtained. A numerical example is considered to illustrate the proposed estimators. Keywords: Approximate Inference; Coverage Probabilities; Joint Type II Censored Sche...

  11. Bipolar I and II disorders in a random and representative Australian population.

    Science.gov (United States)

    Goldney, Robert D; Fisher, Laura J; Grande, Eleonora Dal; Taylor, Anne W; Hawthorne, Graeme

    2005-08-01

    To assess the prevalence of bipolar I and II disorders in an Australian population. The Mood Disorder Questionnaire (MDQ) was administered to 3015 respondents in a random and representative sample in South Australia. Health status, quality of life and demographic data were also collected. There was a 2.5% lifetime prevalence of bipolar I and II disorders delineated by the MDQ. Those people had a significantly greater use of services and a poorer health status and quality of life than those who were MDQ-negative. These results in an Australian population are consistent with other international studies showing a greater prevalence of bipolar disorders than hitherto appreciated.

  12. Non alcoholic fatty liver disease in a Nigerian population with type II ...

    African Journals Online (AJOL)

    Introduction: Worldwide, Non-alcoholic fatty liver disease (NAFLD) has become an important cause of chronic liver disease and cardiovascular morbidity, even more so in subjects with Type II Diabetes Mellitus (T2DM). The aim of this study was to determine the prevalence and risk factors of NAFLD in an African population ...

  13. An Overview on Production and Applications of Ferrate(VI

    Directory of Open Access Journals (Sweden)

    Talaiekhozani

    2016-03-01

    Full Text Available Context Coagulation, chemical oxidation and disinfection are essential processes in water and waste treatment. A chemical that can be applied for all the above mentioned purposes is ferrate(VI. Although there are many studies about ferrate(VI, no comprehensive review paper can be found about ferrate(VI from production to applications. The aim of this study was to review ferrate(VI production, measurement, stability and utilization in water and wastewater treatment. Evidence Acquisition In acidic conditions, the oxidation and reduction capacity of ferrate(VI is superior to all currently utilized oxidizers and disinfectants in water and wastewater treatment. New researches have provided the technology of using ferrate(VI for coagulation, chemical oxidation and disinfection of water and wastewater in a reactor simultaneously, which can reduce the size of water and wastewater treatment plants and increase the treatment efficiency. Results Despite the existence of these technologies, there is no full-scale application of ferrate(VI in the water and wastewater industry which it is due to difficulties associated with I, the lack of adequate researches that have demonstrated its capabilities and advantages over the existing water and wastewater treatment methods; ii, the instability of ferrate(VI depending on its method of preparation, and iii, the relatively low yield of ferrate(VI. Conclusions To solve the above mentioned difficulties, fundamental study most be carried out to discover the novel methods of ferrate(VI production, focusing on increasing the product stability and the production yield.

  14. Vi, de civiliserede

    DEFF Research Database (Denmark)

    Nyemann, Dorthe

    2016-01-01

    Vi har i årtier troet på, at mennesker under de rette omstændigheder kan lykkes med at leve i fred og fordragelighed med hinanden. Skal vi til at erkende, at også vores samfundsstrukturer kun er en tynd fernis ovenpå et utæmmeligt voldspotentiale og egoisme?......Vi har i årtier troet på, at mennesker under de rette omstændigheder kan lykkes med at leve i fred og fordragelighed med hinanden. Skal vi til at erkende, at også vores samfundsstrukturer kun er en tynd fernis ovenpå et utæmmeligt voldspotentiale og egoisme?...

  15. Mechanisms and Rates of U(VI) Reduction by Fe(II) in Homogeneous Aqueous Solution and the Role of U(V) Disproportionation

    Energy Technology Data Exchange (ETDEWEB)

    Collins, Richard N. [UNSW; Rosso, Kevin M. [UNSW; Physical

    2017-08-25

    Molecular-level pathways in the aqueous redox transformation of uranium by iron remain unclear, despite the importance of this knowledge for predicting uranium transport and distribution in natural and engineered environments. As the relative importance of homogeneous versus heterogeneous pathways is difficult to probe experimentally, here we apply computational molecular simulation to isolate rates of key one electron transfer reactions in the homogeneous pathway. By comparison to experimental observations the role of the heterogeneous pathway also becomes clear. Density functional theory (DFT) and Marcus theory calculations for all primary monomeric species at pH values ≤7 show for UO22+ and its hydrolysis species UO2OH+ and UO2(OH)20 that reduction by Fe2+ is thermodynamically favorable, though kinetically limited for UO22+. An inner-sphere encounter complex between UO2OH+ and Fe2+ was the most stable for the first hydrolysis species and displayed an electron transfer rate constant ket = 4.3 × 103 s-1. Three stable inner- and outer-sphere encounter complexes between UO2(OH)20 and Fe2+ were found, with electron transfer rate constants ranging from ket = 7.6 × 102 to 7.2 × 104 s-1. Homogeneous reduction of these U(VI) hydrolysis species to U(V) is, therefore, predicted to be facile. In contrast, homogeneous reduction of UO2+ by Fe2+ was found to be thermodynamically unfavorable, suggesting the possible importance of U(V)-U(V) disproportionation as a route to U(IV). Calculations on homogeneous disproportionation, however, while yielding a stable outer-sphere U(V)-U(V) encounter complex, indicate that this electron transfer reaction is not feasible at circumneutral pH. Protonation of both axial O atoms of acceptor U(V) (i.e., by H3O+) was found to be a prerequisite to stabilize U(IV), consistent with the experimental observation that the rate of this reaction is inversely correlated with pH. Thus, despite prevailing notions that U(V) is rapidly eliminated by

  16. MHC class II diversity of koala (Phascolarctos cinereus) populations across their range.

    Science.gov (United States)

    Lau, Q; Jaratlerdsiri, W; Griffith, J E; Gongora, J; Higgins, D P

    2014-10-01

    Major histocompatibility complex class II (MHCII) genes code for proteins that bind and present antigenic peptides and trigger the adaptive immune response. We present a broad geographical study of MHCII DA β1 (DAB) and DB β1 (DBB) variants of the koala (Phascolarctos cinereus; n=191) from 12 populations across eastern Australia, with a total of 13 DAB and 7 DBB variants found. We identified greater MHCII variation and, possibly, additional gene copies in koala populations in the north (Queensland and New South Wales) relative to the south (Victoria), confirmed by STRUCTURE analyses and genetic differentiation using analysis of molecular variance. The higher MHCII diversity in the north relative to south could potentially be attributed to (i) significant founder effect in Victorian populations linked to historical translocation of bottlenecked koala populations and (ii) increased pathogen-driven balancing selection and/or local genetic drift in the north. Low MHCII genetic diversity in koalas from the south could reduce their potential response to disease, although the three DAB variants found in the south had substantial sequence divergence between variants. This study assessing MHCII diversity in the koala with historical translocations in some populations contributes to understanding the effects of population translocations on functional genetic diversity.

  17. The same ELA class II risk factors confer equine insect bite hypersensitivity in two distinct populations.

    Science.gov (United States)

    Andersson, Lisa S; Swinburne, June E; Meadows, Jennifer R S; Broström, Hans; Eriksson, Susanne; Fikse, W Freddy; Frey, Rebecka; Sundquist, Marie; Tseng, Chia T; Mikko, Sofia; Lindgren, Gabriella

    2012-03-01

    Insect bite hypersensitivity (IBH) is a chronic allergic dermatitis common in horses. Affected horses mainly react against antigens present in the saliva from the biting midges, Culicoides ssp, and occasionally black flies, Simulium ssp. Because of this insect dependency, the disease is clearly seasonal and prevalence varies between geographical locations. For two distinct horse breeds, we genotyped four microsatellite markers positioned within the MHC class II region and sequenced the highly polymorphic exons two from DRA and DRB3, respectively. Initially, 94 IBH-affected and 93 unaffected Swedish born Icelandic horses were tested for genetic association. These horses had previously been genotyped on the Illumina Equine SNP50 BeadChip, which made it possible to ensure that our study did not suffer from the effects of stratification. The second population consisted of 106 unaffected and 80 IBH-affected Exmoor ponies. We show that variants in the MHC class II region are associated with disease susceptibility (p (raw) = 2.34 × 10(-5)), with the same allele (COR112:274) associated in two separate populations. In addition, we combined microsatellite and sequencing data in order to investigate the pattern of homozygosity and show that homozygosity across the entire MHC class II region is associated with a higher risk of developing IBH (p = 0.0013). To our knowledge this is the first time in any atopic dermatitis suffering species, including man, where the same risk allele has been identified in two distinct populations.

  18. Synthesis, characterization, spectroscopic and catalytic oxidation studies of Fe(III), Ni(II), Co(III), V(IV) and U(VI) Schiff base complexes with N, O donor ligands derived from 2,3-diaminopyridine

    Energy Technology Data Exchange (ETDEWEB)

    Zabardasti, Abedien; Shangaie, Sayed Asad [Lorestan Univ., Khorramabad (Iran, Islamic Republic of). Dept. of Chemistry

    2016-10-15

    Fifteen new complexes of transition metals were designed using three Schiff base ligands and aldol condensation of 2,3-diaminopyridine with 5-R-2-hydroxybenzaldehyde (R = F, Cl, Br) in the 1:2 molar ratio. The tetradentate ligands N,N{sup '}-bis(5-R-2-hydroxybenzaldehyde) pyridine were acquired with the common formula H{sub 2}[(5-R-sal){sub 2}py] and characterized by IR, UV-Vis spectra, {sup 1}H-NMR and elemental analysis. These ligands produce 1:1 complexes M[(5-R-sal){sub 2}py] with Fe(III), Ni(II), Co(III), V(IV) and U(VI) metal ions. The electronic property and nature of complexes were identified by IR, UV-Vis spectra, elemental analysis, X-ray crystallography and cyclic voltammetric methods. The catalytic activity of complexes for epoxidation of styrene with UHP as primary oxidant at minimal temperature (10 C) has been planned. The spectral data of the ligands and their complexes are deliberate in connection with the structural changes which happen due to complex preparation. The electrochemical outcome has good conformability with what suggested for electronic interaction among metal center and ligand by the UV-Vis and IR measurements.

  19. FUSE Cycle 3 Program CO22: Chromospheric Activity in Population II Giants

    Science.gov (United States)

    Harper, Graham M.

    2004-01-01

    One of the mysteries of Population II giants is that they still show chromospheric emission despite their great age. The global dynamo which was active during their main-sequence lifetimes is expected to become extremely weak through magnetic rotational braking. The nature of the observed emission is not understood; although acoustic shock waves might provide the heating, acoustic waves are not predicted to drive the observed mass loss - which in turn requires the dissipation of magneto-hydrodynamic waves. This program was designed to search for the faint stellar H Ly(beta) emission wings and the fluorescent Fe II and H2 emission from one of the brightest, metal poor, Population II stars. These FUSE diagnostics, when combined with existing UV and optical spectra, help determine the major radiative cooling channels for the chromosphere. This observation was to complement that previously planned for the mildly metal deficient giant alpha Boo (K2 III). However, a Boo has yet to be observed with FUSE.

  20. and dioxouranium(vi)

    African Journals Online (AJOL)

    a

    Thorium(IV) and uranium(VI) with atomic radii of 1.65 and .... to ν(NH) vibrations. Practically no effect on these frequencies after complexation precludes the possibility of metal-coordination at this group. The absorptions at 1600 ... observation suggests involvement of unsaturated nitrogen atoms of the two azomethine groups.

  1. First light - II. Emission line extinction, population III stars, and X-ray binaries

    Science.gov (United States)

    Barrow, Kirk S. S.; Wise, John H.; Aykutalp, Aycin; O'Shea, Brian W.; Norman, Michael L.; Xu, Hao

    2018-02-01

    We produce synthetic spectra and observations for metal-free stellar populations and high-mass X-ray binaries in the Renaissance Simulations at a redshift of 15. We extend our methodology from the first paper in the series by modelling the production and extinction of emission lines throughout a dusty and metal-enriched interstellar and circum-galactic media extracted from the simulation, using a Monte Carlo calculation. To capture the impact of high-energy photons, we include all frequencies from hard X-ray to far-infrared with enough frequency resolution to discern line emission and absorption profiles. The most common lines in our sample in order of their rate of occurrence are Ly α, the C IV λλ1548, 1551 doublet, H α, and the Ca II λλλ8498, 8542, 8662 triplet. The best scenario for a direct observation of a metal-free stellar population is a merger between two Population III Galaxies. In mergers between metal-enriched and metal-free stellar populations, some characteristics may be inferred indirectly. Single Population III galaxies are too dim to be observed photometrically at z = 15. Ly α emission is discernible by JWST as an increase in J200w - J277w colour off the intrinsic stellar tracks. Observations of metal-free stars will be difficult, though not impossible, with the next generation of space telescopes.

  2. Expression and distribution of type VI collagen in gynecomastia.

    Science.gov (United States)

    Lanzafame, S; Magro, G; Colombatti, A

    1994-06-01

    We investigated the distribution of type VI collagen in 36 cases of routinely fixed and paraffin-embedded gynecomastia using an immunoperoxidase method for light microscopic visualization. Four samples of normal male mammary gland tissue were also included as controls. A protease predigestion was essential for the visualization of this extracellular matrix (ECM) glycoprotein. In normal male breast, no immunoreaction for type VI collagen was detected in the stroma surrounding the ducts. Gynecomastia was classified into three histological types: florid (type I), fibrous (type II), and intermediate (type III). Type VI collagen was differentially expressed in the periductal stroma of all types. This collagen was markedly expressed at the early disease stage (type I) when the periductal stroma is highly cellular and vascular. Its expression decreased when periductal stroma undergoing fibrotic transformation (type III) and completely disappeared from the dense periductal stroma of fibrous stage (type II). These findings suggest that type VI collagen is involved in the ECM remodelling occurring in gynecomastia.

  3. Contribution of extracellular polymeric substances from Shewanella sp. HRCR-1 biofilms to U(VI) immobilization.

    Science.gov (United States)

    Cao, Bin; Ahmed, Bulbul; Kennedy, David W; Wang, Zheming; Shi, Liang; Marshall, Matthew J; Fredrickson, Jim K; Isern, Nancy G; Majors, Paul D; Beyenal, Haluk

    2011-07-01

    The goal of this study was to quantify the contribution of extracellular polymeric substances (EPS) to U(VI) immobilization by Shewanella sp. HRCR-1. Through comparison of U(VI) immobilization using cells with bound EPS (bEPS) and cells with minimal EPS, we show that (i) bEPS from Shewanella sp. HRCR-1 biofilms contribute significantly to U(VI) immobilization, especially at low initial U(VI) concentrations, through both sorption and reduction; (ii) bEPS can be considered a functional extension of the cells for U(VI) immobilization and they likely play more important roles at lower initial U(VI) concentrations; and (iii) the U(VI) reduction efficiency is dependent upon the initial U(VI) concentration and decreases at lower concentrations. To quantify the relative contributions of sorption and reduction to U(VI) immobilization by EPS fractions, we isolated loosely associated EPS (laEPS) and bEPS from Shewanella sp. HRCR-1 biofilms grown in a hollow fiber membrane biofilm reactor and tested their reactivity with U(VI). We found that, when reduced, the isolated cell-free EPS fractions could reduce U(VI). Polysaccharides in the EPS likely contributed to U(VI) sorption and dominated the reactivity of laEPS, while redox active components (e.g., outer membrane c-type cytochromes), especially in bEPS, possibly facilitated U(VI) reduction.

  4. Moderate selenium dosing inhibited chromium (VI) toxicity in chicken liver.

    Science.gov (United States)

    Wang, Yang; Liu, Yongxia; Wan, Huiyu; Zhu, Yiran; Chen, Peng; Hao, Pan; Cheng, Ziqiang; Liu, Jianzhu

    2017-08-01

    This study aimed to clarify the effect of selenium (Se) on chromium (VI) [Cr(VI)]-induced damage in chicken liver. A total of 105 chickens were randomly divided into seven groups of 15. Group I received deionized water; group II received Cr(VI) (7.83 mg/kg/d) alone; and other groups orally received both Cr(VI) (7.83 mg/kg/d) and Se of different doses (0.14, 0.29, 0.57, 1.14, and 2.28 mg/kg/d). The levels of superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA), Ca2+ -ATPase, and mitochondrial membrane potential (MMP) were measured. Results showed that Cr(VI) increased MDA content and decreased GSH content, T-SOD activity, Ca2+ -ATPase activity, and MMP level. Meanwhile, Se co-treatment (0.14, 0.29, and 0.57 mg/kg/d) increased the viability of the above indicators compared with Cr(VI)-treatment alone. In addition, histopathologic examination revealed that Cr(VI) can cause liver damage, whereas Se supplementation of moderate dose inhibited this damage. This study confirmed that Se exerted protective effect against Cr(VI)-induced liver damage. © 2017 Wiley Periodicals, Inc.

  5. The Relation Between Inflation in Type-I and Type-II Error Rate and Population Divergence in Genome-Wide Association Analysis of Multi-Ethnic Populations.

    Science.gov (United States)

    Derks, E M; Zwinderman, A H; Gamazon, E R

    2017-05-01

    Population divergence impacts the degree of population stratification in Genome Wide Association Studies. We aim to: (i) investigate type-I error rate as a function of population divergence (F ST ) in multi-ethnic (admixed) populations; (ii) evaluate the statistical power and effect size estimates; and (iii) investigate the impact of population stratification on the results of gene-based analyses. Quantitative phenotypes were simulated. Type-I error rate was investigated for Single Nucleotide Polymorphisms (SNPs) with varying levels of F ST between the ancestral European and African populations. Type-II error rate was investigated for a SNP characterized by a high value of F ST . In all tests, genomic MDS components were included to correct for population stratification. Type-I and type-II error rate was adequately controlled in a population that included two distinct ethnic populations but not in admixed samples. Statistical power was reduced in the admixed samples. Gene-based tests showed no residual inflation in type-I error rate.

  6. Contribution of Extracellular Polymeric Substances from Shewanella sp. HRCR-1 Biofilms to U(VI) Immobilization

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Bin; Ahmed, B.; Kennedy, David W.; Wang, Zheming; Shi, Liang; Marshall, Matthew J.; Fredrickson, Jim K.; Isern, Nancy G.; Majors, Paul D.; Beyenal, Haluk

    2011-06-05

    The goal of this study was to quantify the contribution of extracellular polymeric substances (EPS) in U(VI) immobilization by Shewanella sp. HRCR-1. Through comparison of U(VI) immobilization using cells with bound EPS (bEPS) and cells without EPS, we showed that i) bEPS from Shewanella sp. HRCR-1 biofilms contributed significantly to U(VI) immobilization, especially at low initial U(VI) concentrations, through both sorption and reduction; ii) bEPS could be considered as a functional extension of the cells for U(VI) immobilization and they likely play more important roles at initial U(VI) concentrations; and iii) U(VI) reduction efficiency was found to be dependent upon initial U(VI) concentration and the efficiency decreased at lower concentrations. To quantify relative contribution of sorption and reduction in U(VI) immobilization by EPS fractions, we isolated loosely associated EPS (laEPS) and bEPS from Shewanella sp. HRCR-1 biofilms grown in a hollow fiber membrane biofilm reactor and tested their reactivity with U(V). We found that, when in reduced form, the isolated cell-free EPS fractions could reduce U(VI). Polysaccharides in the EPS likely contributed to U(VI) sorption and dominated reactivity of laEPS while redox active components (e.g., outer membrane c-type cytochromes), especially in bEPS, might facilitate U(VI) reduction.

  7. HLA class I and class II associations with ESRD in Saudi Arabian population.

    Directory of Open Access Journals (Sweden)

    Nuha Mahmoud Hamdi

    Full Text Available Chronic renal failure (CRF leads in the majority of instances to end stage renal disease (ESRD requiring renal replacement therapy. Our interest was to evaluate the possible associations of HLA class I and class II antigens with ESRD independent of other factors, in Saudi Arabia population.A retrospective study to determine the HLA class I and class II polymorphisms and their association with ESRD, was performed on 350 patients with ESRD, and 105 healthy unrelated control. Patients and control groups were typed by SSOP lumenix techniques. The alleles positively associated to the ESRD were: HLA-B*15, B*18, B*49 - DRB1*03, negatively associated alleles were A*26, HLA-B*39, B*50. The haplotypes positively associated with ESRD were: HLA-A*01-DRB1*13 and HLA-A*30-DRBI*03. The negatively associated haplotypes were: HLA-A*02-B*39, A*02-B*50, A*24-B*35, A*24-B*58, A*24-DRB1*16, A*68-DRB1*04, A*02-DQB1*03, A*29-DQB1*02, A*29-DOB1*05 and B*27-DRB1*07 and the last one is the most significant protective haplotypes.The high Relative Risk (RR observed and its statistical correlation reflect the strength of the described association between HLA antigens and ESRD.

  8. HLA Class I and Class II Associations with ESRD in Saudi Arabian Population

    Science.gov (United States)

    Hamdi, Nuha Mahmoud; Al-Hababi, Fadel Hassan; Eid, Amr Ekhlas

    2014-01-01

    Background Chronic renal failure (CRF) leads in the majority of instances to end stage renal disease (ESRD) requiring renal replacement therapy. Our interest was to evaluate the possible associations of HLA class I and class II antigens with ESRD independent of other factors, in Saudi Arabia population. Methodology A retrospective study to determine the HLA class I and class II polymorphisms and their association with ESRD, was performed on 350 patients with ESRD, and 105 healthy unrelated control. Patients and control groups were typed by SSOP lumenix techniques. The alleles positively associated to the ESRD were: HLA-B*15, B*18, B*49 - DRB1*03, negatively associated alleles were A*26, HLA-B*39, B*50. The haplotypes positively associated with ESRD were: HLA-A*01-DRB1*13 and HLA-A*30-DRBI*03. The negatively associated haplotypes were: HLA-A*02-B*39, A*02-B*50, A*24-B*35, A*24-B*58, A*24-DRB1*16, A*68-DRB1*04, A*02-DQB1*03, A*29-DQB1*02, A*29-DOB1*05 and B*27-DRB1*07 and the last one is the most significant protective haplotypes. Conclusion The high Relative Risk (RR) observed and its statistical correlation reflect the strength of the described association between HLA antigens and ESRD. PMID:25380295

  9. New approach in modeling Cr(VI) sorption onto biomass from metal binary mixtures solutions

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Chang [College of Environmental Science and Engineering, Anhui Normal University, South Jiuhua Road, 189, 241002 Wuhu (China); Chemical Engineering Department, Escola Politècnica Superior, Universitat de Girona, Ma Aurèlia Capmany, 61, 17071 Girona (Spain); Fiol, Núria [Chemical Engineering Department, Escola Politècnica Superior, Universitat de Girona, Ma Aurèlia Capmany, 61, 17071 Girona (Spain); Villaescusa, Isabel, E-mail: Isabel.Villaescusa@udg.edu [Chemical Engineering Department, Escola Politècnica Superior, Universitat de Girona, Ma Aurèlia Capmany, 61, 17071 Girona (Spain); Poch, Jordi [Applied Mathematics Department, Escola Politècnica Superior, Universitat de Girona, Ma Aurèlia Capmany, 61, 17071 Girona (Spain)

    2016-01-15

    In the last decades Cr(VI) sorption equilibrium and kinetic studies have been carried out using several types of biomasses. However there are few researchers that consider all the simultaneous processes that take place during Cr(VI) sorption (i.e., sorption/reduction of Cr(VI) and simultaneous formation and binding of reduced Cr(III)) when formulating a model that describes the overall sorption process. On the other hand Cr(VI) scarcely exists alone in wastewaters, it is usually found in mixtures with divalent metals. Therefore, the simultaneous removal of Cr(VI) and divalent metals in binary mixtures and the interactive mechanism governing Cr(VI) elimination have gained more and more attention. In the present work, kinetics of Cr(VI) sorption onto exhausted coffee from Cr(VI)–Cu(II) binary mixtures has been studied in a stirred batch reactor. A model including Cr(VI) sorption and reduction, Cr(III) sorption and the effect of the presence of Cu(II) in these processes has been developed and validated. This study constitutes an important advance in modeling Cr(VI) sorption kinetics especially when chromium sorption is in part based on the sorbent capacity of reducing hexavalent chromium and a metal cation is present in the binary mixture. - Highlights: • A kinetic model including Cr(VI) reduction, Cr(VI) and Cr(III) sorption/desorption • Synergistic effect of Cu(II) on Cr(VI) elimination included in the model • Model validation by checking it against independent sets of data.

  10. Angiotensin II type 1 receptor (A1166C gene polymorphism and essential hypertension in Egyptian population

    Directory of Open Access Journals (Sweden)

    Marium M. Shamaa

    2016-09-01

    Full Text Available The pathogenesis of essential hypertension (EH is affected by genetic and environmental factors. Mutations in hypertension-related genes can affect blood pressure (BP via alteration of salt and water reabsorption by the nephron. The genes of the renin-angiotensin system (RAS have been extensively studied because of the well documented role of this system in the control of BP. It has been previously shown that Angiotensin II type 1 receptor (ATR1 gene polymorphism could be associated with increased risk of EH. So, in the current study, we evaluated the frequency of ATR1 (A1166C polymorphism in relation to EH in a group of Egyptian population. The study population included 83 hypertensive patients and 60 age and sex matched healthy control subjects. Restriction fragment length polymorphism – Polymerase chain reaction (RFLP – PCR was used for the analysis of A1166C polymorphism of ATR1 genes in peripheral blood samples of all patients and controls. The results revealed that there was a positive risk of developing EH when having the T allele whether in homozygous or heterozygous state. From this work, it was concluded that there was an association between ATR1 (A1166C gene polymorphism and the risk of developing EH.

  11. HLA-class II genes in Mexican Amerindian Mayas: relatedness with Guatemalan Mayans and other populations.

    Science.gov (United States)

    Vargas-Alarcón, Gilberto; Granados, Julio; Pérez-Hernández, Nonanzit; Rodríguez-Pérez, José Manuel; Canto-Cetina, Thelma; Coral-Vázquez, Ramón Mauricio; Areces, Cristina; Gómez-Prieto, Pablo; Arnaiz-Villena, Antonio

    2011-01-01

    We analyzed the HLA class II allele frequencies in 50 healthy unrelated Mayan individuals. The relationship with other worldwide populations was studied by using HLA data from 71 different populations. The most frequent alleles were HLA-DRB1*04, HLA-DRB1*01, HLA-DQB1*0302 and HLA-DQB1*0501. When comparisons with other Mexican Amerindian groups were made, some differences were observed. Mayans showed an increased frequency of HLA-DRB1*01 when compared to Nahuas, Mayos, Teenek and Mazatecans (p Nahuas (p Nahuas and Mazatecans (p Nahuas, Mayos, Teenek and Mazatecans (p Nahuas was found. Neighbour Joining dendrogram shows that Mexican Mayans are genetically close to some of the most ancient groups living in Mexico and some South American Amerindians. However, Guatemalan Mayans do not cluster together with Mexican Mayas showing that languages do not correlate with genes, particularly in Amerindians. The data corroborate the restricted polymorphism of HLA-DRB1 and DQB1 alleles and the high frequency of HLA-DRB1*04 and HLA-DQB1*0302 in Mayans from Mexico.

  12. Protostars and Planets VI

    Science.gov (United States)

    Beuther, Henrik; Klessen, Ralf S.; Dullemond, Cornelis P.; Henning, Thomas

    The Protostars and Planets book and conference series has been a long-standing tradition that commenced with the first meeting led by Tom Gehrels and held in Tucson, Arizona, in 1978. The goal then, as it still is today, was to bridge the gap between the fields of star and planet formation as well as the investigation of planetary systems and planets. As Tom Gehrels stated in the preface to the first Protostars and Planets book, "Cross-fertilization of information and understanding is bound to occur when investigators who are familiar with the stellar and interstellar phases meet with those who study the early phases of solar system formation." The central goal remained the same for the subsequent editions of the books and conferences Protostars and Planets II in 1984, Protostars and Planets III in 1990, Protostars and Planets IV in 1998, and Protostars and Planets V in 2005, but has now been greatly expanded by the flood of new discoveries in the field of exoplanet science. The original concept of the Protostars and Planets series also formed the basis for the sixth conference in the series, which took place on July 15-20, 2013. It was held for the first time outside of the United States in the bustling university town of Heidelberg, Germany. The meeting attracted 852 participants from 32 countries, and was centered around 38 review talks and more than 600 posters. The review talks were expanded to form the 38 chapters of this book, written by a total of 250 contributing authors. This Protostars and Planets volume reflects the current state-of-the-art in star and planet formation, and tightly connects the fields with each other. It is structured into four sections covering key aspects of molecular cloud and star formation, disk formation and evolution, planetary systems, and astrophysical conditions for life. All poster presentations from the conference can be found at www.ppvi.org. In the eight years that have passed since the fifth conference and book in the

  13. Method for making graded I-III-VI.sub.2 semiconductors and solar cell obtained thereby

    Science.gov (United States)

    Devaney, Walter E.

    1987-08-04

    Improved cell photovoltaic conversion efficiencies are obtained by the simultaneous elemental reactive evaporation process of Mickelsen and Chen for making semiconductors by closer control of the evaporation rates and substrate temperature during formation of the near contact, bulk, and near junction regions of a graded I-III-VI.sub.2, thin film, semiconductor, such as CuInSe.sub.2 /(Zn,Cd)S or another I-III-VI.sub.2 /II-VI heterojunction.

  14. Vi tror, vi forstår hinanden, men det gør vi ikke

    DEFF Research Database (Denmark)

    Boysen, Mikkel Snorre Wilms

    2016-01-01

    Vores verdensbillede er baseret på en tro på, at vi forstår hinanden. Men meget tyder på, at denne tro snarere er en illusion. Derfor må vi indstille os på, at der skal en særlig indsats til, hvis vi skal kunne forstå vores omverden og menneskene i den......Vores verdensbillede er baseret på en tro på, at vi forstår hinanden. Men meget tyder på, at denne tro snarere er en illusion. Derfor må vi indstille os på, at der skal en særlig indsats til, hvis vi skal kunne forstå vores omverden og menneskene i den...

  15. and Cr(VI) ions by chitosan: kinetics and equilibrium studies

    African Journals Online (AJOL)

    The ability of chitosan as an adsorbent for Cu (II) and Cr (VI) ions in aqueous solution was studied. The experiments were done as batch processes. Equilibrium studies were done on both cross-linked and non-cross-linked chitosan for both metals. Cr (VI) adsorption behaviour could be described using the Langmuir ...

  16. The Rome II and Rome III criteria identify the same subtype-populations in irritable bowel syndrome

    DEFF Research Database (Denmark)

    Engsbro, A L; Simrén, M; Bytzer, P

    2012-01-01

    For comparing trials using different classifications for irritable bowel syndrome (IBS) subtypes, it is important to know whether these identify the same sub-populations. Our aim was to determine the agreement between Rome II and Rome III subtypes, and to explore whether agreement depends...

  17. Reference Values for the Revised Anti-Müllerian Hormone Generation II Assay: Infertile Population-based Study.

    Science.gov (United States)

    Lee, Joong Yeup; Ahn, Soyeon; Lee, Jung Ryeol; Jee, Byung Chul; Kim, Chung Hyon; Seo, Soyeon; Suh, Chang Suk; Kim, Seok Hyun

    2017-05-01

    Anti-Müllerian hormone (AMH) is now accepted as an important clinical marker of ovarian reserve and is increasingly measured as an initial evaluation at infertility clinics. The aim of this study was to establish reference values for the revised second generation (Gen II) assay using population-based data. In this population-based cohort study, AMH data from unselected infertile women aged 25-45 years from June 2013 to June 2014 (n = 15,801) were collected. The AMH values were measured using the revised Gen II assay. We established and validated 5 AMH-age regression models. Based on the optimal AMH-age model, reference values and centile charts were obtained. The quadratic model (log AMH = 0.410 × age -0.008 × age² -3.791) was the most appropriate for describing the age-dependent decrease in AMH measured using the revised Gen II assay. This is the largest population-based study to establish age-specific reference values of AMH using the revised Gen II assay. These reference values may provide more specific information regarding the ovarian reserve estimation of infertile women. © 2017 The Korean Academy of Medical Sciences.

  18. The prognostic importance of miR-21 in stage II colon cancer: a population-based study

    DEFF Research Database (Denmark)

    Kjaer-Frifeldt, S.; Hansen, T. F.; Nielsen, B. S.

    2012-01-01

    BACKGROUND: Despite several years of research and attempts to develop prognostic models a considerable fraction of stage II colon cancer patients will experience relapse within few years from their operation. The aim of the present study was to investigate the prognostic importance of miRNA-21 (mi......R-21), quantified by in situ hybridisation, in a unique, large population-based cohort. PATIENTS AND METHODS: The study included 764 patients diagnosed with stage II colon cancer in Denmark in the year 2003. One section from a representative paraffin-embedded tumour tissue specimen from each patient...

  19. Applicability of a submersible microbial fuel cell for Cr(VI) detection in water.

    Science.gov (United States)

    Chung, Hyeonyong; Ju, Won Jung; Jho, Eun Hea; Nam, Kyoungphile

    2016-11-01

    Two-chamber microbial fuel cells (MFCs) were used to study the applicability of MFCs for hexavalent chromium (Cr(VI)) detection in water. The microbial acetate oxidation in the anode and the Cr(VI) reduction in the cathode together generated voltages, which were used to indicate the change in Cr(VI) concentrations of the cathode under varying conditions of pH, ionic strength, co-existing Fe(II) concentration, and organic matter concentration. The MFC-based Cr(VI) detector showed a significant change in voltage with increasing Cr(VI) concentration at pH 1 and 2, but not at higher pH conditions. The detector also successfully measured the changes in Cr(VI) concentration at a range of ionic strength (i.e., 10-300 mM), and in the presence of different concentrations of fulvic acid (0-50 mg/L), which was used as a surrogate of organic matters, without interference. The Cr(VI) detection was not interfered by the presence of Fe(II) at the Cr(VI)/Fe(II) ratio of 1:1 and 1:15, but it was interfered at higher ratios (i.e., 1:164 and 1:848). The detector could measure the Cr(VI) concentration from 0.1 to 15 mg/L at pH 2. Overall, the MFC-based Cr(VI) detector may be applied to meet the growing need of real-time Cr(VI) monitoring in water.

  20. ViFiLite Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ViFiLite is a wireless infrastructure that utilizes the advantages of a V-band technology in supporting data gathering for structural health monitoring as well as...

  1. Skal vi have flere krondyr?

    DEFF Research Database (Denmark)

    Pedersen, Jens Christian

    2008-01-01

    Vi kunne have væsentligt flere krondyr i den danske natur end vi har i øjeblikket. Den primære årsag er jagt. Det viser en ny undersøgelse fra Danmarks Miljøundersøgelser ved Aarhus Universitet. Bestanden af krondyr er ganske vist steget meget siden 1970, men der er både plads og føde til mange...

  2. Discharge from total populations of Ia and II afferent fibers in the cat's deefferented medial gastrocnemius muscle during static stretch.

    Science.gov (United States)

    Botterman, B R; Eldred, E

    1983-04-01

    Estimates were made of the changing volumes of discharge arising from the total populations of Ia and II spindle afferent fibers in the cat's deefferented medial gastrocnemius as the muscle was extended stepwise over its excursion range. The estimates were based on values reported elsewhere for (i) the incidence of active units and (ii) their rates of discharge at static muscle lengths normalized against the excursion range of the particular muscle, together with (iii) the numbers of Ia and II afferent fibers in the medial gastrocnemius as derived from a critical review of published information. Curves representing the total discharge of the two afferent types are similar and show three phases: an initial level of spontaneous activity, a somewhat curvilinear rise associated with early recruitment of units during stretch, and rectilinear increase after full recruitment. There was no appearance of saturation. Completion of recruitment of both types of units occurred about halfway in the extension range of the passive muscle. Over most of the excursion range, inflow from the group II population was about one-third greater than that from the Ia units.

  3. Evidences for balancing selection from PAH-BglII and PAH-EcoRI polymorphisms in Isfahan population

    Directory of Open Access Journals (Sweden)

    Zahra Fazeli Attar

    2010-01-01

    Full Text Available Two polymorphic markers including BglII and EcoRI, were identified at intron 1 and intron 5 of PAH gene. In order to test whether these polymorphisms are behaving as neutral alleles or are being subjected to selective pressures in Isfahan population, 110 individuals were genotyped by PCR-RFLP. The Arlequin input file was prepared by use of phase-known haplotype data and Neutrality tests (Tajima D test and Fu’s Fs test were done using Arlequin program. 42 individuals were found heterozygous for both polymorphisms whose haplotype phase remained unknown. The BglII-EcoRI haplotype phase was known only at 68 individuals who were used for preparation of input file. Tajima's D value and Fs value at Isfahan population were 1.7 and 1.02, respectively. Positive values of Fs and D>0 indicated that these polymorphisms are under selection pressure at Isfahan population. Although these polymorphisms were in the non-coding region of PAH gene, but these were not neutral alleles and positive values of these tests provided evidence for balancing selection of these polymorphisms at Isfahan population. The results of this study could improve our understanding of evolutionary history and structure of Isfahan population.

  4. Beck Depression Inventory II: evaluation of the psychometric properties and cut-off points in a Turkish adult population.

    Science.gov (United States)

    Kapci, Emine Gul; Uslu, R; Turkcapar, H; Karaoglan, A

    2008-01-01

    Numerous studies have been previously conducted to assess the Beck Depression Inventory-II's [BDI II; Beck et al., 1996] psychometric properties. However, none of these studies has examined whether the original cut-off scores were applicable to other cultures. Thus, in addition to evaluating its psychometric properties, we also determined the cut-off scores of the BDI II for the Turkish population. Data from nonclinical (n = 362) and clinical psychiatric outpatients diagnosed as depressive disorder according to DSM-IV criteria (n = 176) were gathered. Analyses for internal consistency and test-retest reliabilities and for convergent and discriminant validities were computed. Two confirmatory factor analyses, one derived from the present exploratory factor analyses and the other proposed in the original study were conducted for both groups. A receiver operating characteristics curve was utilized to determine the cut-off scores for the Turkish population revealing 0-12 for minimal, 13-18 for mild, 19-28 for moderate and 29-63 for severe depression. The internal consistency for the nonclinical and clinical groups were .90 and .89, respectively; test-retest stability was also high (r = .94). Convergent and discriminant validity results were satisfactory. Findings confirmed the present model for the clinical group and equally confirmed both models for the nonclinical group. Furthermore, the cut-off scores to classify minimal, mild, moderate, and severe depression were quite akin to the cut-off points previously suggested for the American population. Taken as a whole our findings revealed that BDI II has sound psychometric properties and comparable cut-off scores for the Turkish population. Depression and Anxiety, 2008. (c) 2007 Wiley-Liss, Inc.

  5. A massive, quiescent, population II galaxy at a redshift of 2.1.

    Science.gov (United States)

    Kriek, Mariska; Conroy, Charlie; van Dokkum, Pieter G; Shapley, Alice E; Choi, Jieun; Reddy, Naveen A; Siana, Brian; van de Voort, Freeke; Coil, Alison L; Mobasher, Bahram

    2016-12-07

    Unlike spiral galaxies such as the Milky Way, the majority of the stars in massive elliptical galaxies were formed in a short period early in the history of the Universe. The duration of this formation period can be measured using the ratio of magnesium to iron abundance ([Mg/Fe]) in spectra, which reflects the relative enrichment by core-collapse and type Ia supernovae. For local galaxies, [Mg/Fe] probes the combined formation history of all stars currently in the galaxy, including younger and metal-poor stars that were added during late-time mergers. Therefore, to directly constrain the initial star-formation period, we must study galaxies at earlier epochs. The most distant galaxy for which [Mg/Fe] had previously been measured is at a redshift of z ≈ 1.4, with [Mg/Fe] = . A slightly earlier epoch (z ≈ 1.6) was probed by combining the spectra of 24 massive quiescent galaxies, yielding an average [Mg/Fe] = 0.31 ± 0.12 (ref. 7). However, the relatively low signal-to-noise ratio of the data and the use of index analysis techniques for both of these studies resulted in measurement errors that are too large to allow us to form strong conclusions. Deeper spectra at even earlier epochs in combination with analysis techniques based on full spectral fitting are required to precisely measure the abundance pattern shortly after the major star-forming phase (z > 2). Here we report a measurement of [Mg/Fe] for a massive quiescent galaxy at a redshift of z = 2.1, when the Universe was three billion years old. With [Mg/Fe] = 0.59 ± 0.11, this galaxy is the most Mg-enhanced massive galaxy found so far, having twice the Mg enhancement of similar-mass galaxies today. The abundance pattern of the galaxy is consistent with enrichment exclusively by core-collapse supernovae and with a star-formation timescale of 0.1 to 0.5 billion years-characteristics that are similar to population II stars in the Milky Way. With an average past star

  6. Characterization of Citrobacter sp. line 328 as a source of Vi for a Vi-CRM(197) glycoconjugate vaccine against Salmonella Typhi.

    Science.gov (United States)

    Rondini, Simona; Micoli, Francesca; Lanzilao, Luisa; Pisoni, Ivan; Di Cioccio, Vito; Saul, Allan J; Martin, Laura B

    2012-11-26

    Salmonella enterica serovar Typhi is the causative agent of typhoid fever with over 22 million cases and over 200,000 deaths reported annually. A vaccine is much needed for use in young children and the Novartis Vaccines Institute for Global Health (NVGH) is developing a conjugate vaccine which targets S. Typhi Vi capsular polysaccharide. Here we describe a method suitable for industrial scale production of the Vi antigen based on expression by a Citrobacter line. We optimized the production of Vi by selecting a suitable Citrobacter strain (Citrobacter 328) that yields high and stable expression of Vi in chemically defined medium under industrial-scale fermentation conditions. Vi-CRM197 made using Vi from Citrobacter 328 elicited high anti-Vi antibody levels in mice and rabbits. Citrobacter 328 is a suitable strain for production of Vi for conjugate anti-Typhi vaccines. Being a BSL-1 organism, which grows in defined medium and stably produces high yields of Vi, it offers excellent potential for safe production of inexpensive vaccines for populations at risk of typhoid fever.

  7. Type II antithrombin deficiency caused by a founder mutation Pro73Leu in the Finnish population: clinical picture.

    Science.gov (United States)

    Puurunen, M; Salo, P; Engelbarth, S; Javela, K; Perola, M

    2013-10-01

    It has been shown that some antithrombin (AT) activity assays do not correctly detect inherited type II AT deficiency, but erroneously classify these patients as normal. Our aim was to investigate the mutations causing type II AT deficiency and to correlate the AT activity results with the genetic findings. A large population (n = 104; 42 families) of Finnish patients with known AT type II deficiency were interviewed for clinical data. Their AT activity was measured with five commercially available methods, and the SERPINC1 gene was genotyped. The mutations detected in type II AT-deficient patients were as follows: p.Pro73Leu (AT Basel) in 37 of 42 (88.1%) families; and p.Val30Glu, p.Arg425Cys and p.Pro439Ala in one family each. In two families, no mutation was detected. In the carriers of AT Basel two AT activity assays correctly identified most of the patients as AT-deficient, whereas three assays misclassified almost all of these patients as normal. Carriers of the founder mutation had, in addition to an elevated risk of venous thrombosis, a high risk of arterial thrombosis at young age, especially stroke. In Finland, a population with a strong founder effect, AT type II deficiency is caused predominantly by a single point mutation, p.Pro73Leu. The mutation is associated with a significant thrombotic risk. Reduced AT activity caused by this mutation cannot be detected by all available screening methods. This must be taken into account in the choice of laboratory method used for screening. © 2013 International Society on Thrombosis and Haemostasis.

  8. Chemical evolution of the Galactic bulge as traced by microlensed dwarf and subgiant stars. VI. Age and abundance structure of the stellar populations in the central sub-kpc of the Milky Way

    Science.gov (United States)

    Bensby, T.; Feltzing, S.; Gould, A.; Yee, J. C.; Johnson, J. A.; Asplund, M.; Meléndez, J.; Lucatello, S.; Howes, L. M.; McWilliam, A.; Udalski, A.; Szymański, M. K.; Soszyński, I.; Poleski, R.; Wyrzykowski, Ł.; Ulaczyk, K.; Kozłowski, S.; Pietrukowicz, P.; Skowron, J.; Mróz, P.; Pawlak, M.; Abe, F.; Asakura, Y.; Bhattacharya, A.; Bond, I. A.; Bennett, D. P.; Hirao, Y.; Nagakane, M.; Koshimoto, N.; Sumi, T.; Suzuki, D.; Tristram, P. J.

    2017-09-01

    We present a detailed elemental abundance study of 90 F and G dwarf, turn-off, and subgiant stars in the Galactic bulge. Based on high-resolution spectra acquired during gravitational microlensing events, stellar ages and abundances for 11 elements (Na, Mg, Al, Si, Ca, Ti, Cr, Fe, Zn, Y and Ba) have been determined. Four main findings are presented: (1) a wide metallicity distribution with distinct peaks at [Fe/H] = -1.09, -0.63, -0.20, + 0.12, + 0.41; (2) ahigh fraction of intermediate-age to young stars where at [Fe/H] > 0 more than 35% are younger than 8 Gyr, and for [Fe/H] ≲ -0.5 most stars are 10 Gyr or older; (3) several episodes of significant star formation in the bulge has been identified: 3, 6, 8, and 11 Gyr ago; (4) tentatively the "knee" in the α-element abundance trends of the sub-solar metallicity bulge is located at a slightly higher [Fe/H] than in the local thick disk. These findings show that the Galactic bulge has complex age and abundance properties that appear to be tightly connected to the main Galactic stellar populations. In particular, the peaks in the metallicity distribution, the star formation episodes, and the abundance trends, show similarities with the properties of the Galactic thin and thick disks. At the same time, the star formation rate appears to have been slightly faster in the bulge than in the local thick disk, which most likely is an indication of the denser stellar environment closer to the Galactic centre. There are also additional components not seen outside the bulge region, and that most likely can be associated with the Galactic bar. Our results strengthen the observational evidence that support the idea of a secular origin for the Galactic bulge, formed out of the other main Galactic stellar populations present in the central regions of our Galaxy. Additionally, our analysis of this enlarged sample suggests that the (V-I)0 colour of the bulge red clump should be revised to 1.09. Based on data obtained with the

  9. CHROMIUM(VI REDUCTION BY A MIXED CULTURE OF SULFATE REDUCING BACTERIA DEVELOPED IN COLUMN REACTOR

    Directory of Open Access Journals (Sweden)

    Cynthia Henny

    2008-03-01

    Full Text Available A lactate enriched mixed sulfate reducing bacteria (SRB culture was examined for the reduction of Cr(VI in a continuous flow system. The influent was mineral salts media added with lactate and sulfate with amounts of 8 and 6 mM respectively as electron donor and electron acceptor. The SRB culture was allowed to stabilize in the column before adding the Cr(VI to the influent. Chromium and sulfate reduction and lactate oxidation were examined by measuring the concentrations of Cr(Vl, sulfate and lactate in the influent and the effluent over time. The experiment was discontinued when Cr(VI concentration in the effiuent was breakthrough. In the absence of Cr(VI, sulfate was not completely reduced in the column, although lactate was completely oxidized and acetate as an intermediate product was not often detected. Almost all of Cr(VI loaded was reduced in the column seeded with the SRB culture at influent Cr(VI concentrations of 192,385 and769 mM. There was no significant Cr(VI loss in the control column, indicating that Cr(VI removal was due to the reduction of Cr(VI to Cr (lll by the SRB culture. The instantaneous Cr(VI removal decreased to a minimum of 32%, 24 days after the influent Cr(VI concentration was increased to 1540 mM, ancl sulfate removal efficiency decreased to a minimum of 17%. The SRB population in the column decreased 100 days after C(VI was added to the column. The total mass of Cr(VI reduced was approximately 878 mmol out of 881 mmol of Cr(Vl loaded in 116 days. The results clearly show that our developed SRB culture could reduced Cr(Vl considerably.

  10. Situação da arborização viária e proposta de espécies para os bairros Antônio Zanaga I e II, da cidade de Americana/SP

    OpenAIRE

    Luzia Ferreira da Silva

    2005-01-01

    Os objetivos deste trabalho foram avaliar a situação da arborização viária em dois bairros de Americana/SP, apresentar dados que possam servir de base para seu plano diretor de arborização urbana, escolher espécies para plantio nas calçadas, junto à população local, e colaborar no envolvimento dos moradores na solução dos freqüentes problemas relacionados à educação ambiental. Na primeira fase, foi feito um inventário das árvores existentes, analisando as espécies mais freqüentes, suas condiç...

  11. Managed care's clinical and economic impact on patients with type II diabetes in France: a controlled population-based study.

    Science.gov (United States)

    Boyer, Laurent; François, Patrice; Fourny, Magali; Ohrond, Céline; Chanut, Charles; Labarère, José; Auquier, Pascal

    2008-01-01

    The purpose of this paper is to assess the impact of five type II diabetes managed care programmes (MCPs) in clinical and economic terms at the community level in which these programmes function in the Provence-Alpes-Côte d'Azur region of France. A prospective, controlled, before-and-after study (2001-2004) compared diabetic patients who lived in departments (localities) with (the experimental group) and without a MCP (the control group). Quality of care was estimated by the conformity of health care professionals' practices when following-up type II diabetes. Costs are compared from a health service perspective. The study finds that of 626 patients enrolled, 529 lived in departments with an MCP and 97 patients in departments without. Type II diabetes follow-up globally improved between the two study periods (2001 and 2004), but the study did not show significant differences between the two groups, except for the proportion of creatinine and ophthalmologic examinations, which were higher for the control group. The study did not find significant differences in the increase of costs between the two groups from 2001 to 2004. This type of study could constitute a methodological model to assess the MCPs population impact. MCPs probably did not reach a critical size in terms of patient recruitment and healthcare professional adhesion to have a significant impact at a population level. The study highlights a number of points to consider for future MCPs in France.

  12. BEHA VI OUR OF TOPI IN A SHADELESS ENVIRONMENT ...

    African Journals Online (AJOL)

    BEHA VI OUR OF TOPI IN A SHADELESS ENVIRONMENT. P. J. JARMAN-. Department of ... them for much of the year medium-length, fairly green, leafy swards of grass. The vegetation types containing ... one population for signs of behavioural adaptiveness in the species' environmental relation- ships. -Present address: ...

  13. German population of Ukraine during the world war ii in the context of modern Ukrainian historiography

    Directory of Open Access Journals (Sweden)

    Людмила Алексеевна Радченко

    2017-01-01

    Full Text Available This article touched previously taboo in Soviet historical science topic related to the fate of ethnic Germans who lived during the WW II in the territory of Ukraine occupied by the Wehrmacht. It was emphasized that the first researchers insisted on the need for a balanced analysis of this issue

  14. He II emitters in the VIMOS VLT Deep Survey: Population III star formation or peculiar stellar populations in galaxies at 2 < z < 4.6?

    Science.gov (United States)

    Cassata, P.; Le Fèvre, O.; Charlot, S.; Contini, T.; Cucciati, O.; Garilli, B.; Zamorani, G.; Adami, C.; Bardelli, S.; Le Brun, V.; Lemaux, B.; Maccagni, D.; Pollo, A.; Pozzetti, L.; Tresse, L.; Vergani, D.; Zanichelli, A.; Zucca, E.

    2013-08-01

    Aims: The aim of this work is to identify He II emitters at 2 1200 km s-1), 3 active galactic nuclei (AGN), and an additional 12 possible He II emitters. The properties of the individual broad emitters are in agreement with expectations from a Wolf-Rayet (W-R) model. Instead, the properties of the narrow emitters are not compatible with this model, nor with predictions of gravitational cooling radiation produced by gas accretion, unless this is severely underestimated by current models by more than two orders of magnitude. Rather, we find that the EW of the narrow He II line emitters are in agreement with expectations for a Population III (PopIII) star formation, if the episode of star formation is continuous, and we calculate that a PopIII star formation rate (SFR) of 0.1-10 M⊙ yr-1 alone is enough to sustain the observed He II flux. Conclusions: We conclude that narrow He II emitters are powered either by the ionizing flux from a stellar population rare at z ~ 0 but much more common at z ~ 3, or by PopIII star formation. As proposed by Tornatore and collaborators, incomplete interstellar medium mixing may leave some small pockets of pristine gas at the periphery of galaxies from which PopIII may form, even down to z ~ 2 or lower. If this interpretation is correct, we measure at z ~ 3 a star formation rate density in PopIII stars of 10-6 M⊙ yr-1 Mpc-3, higher than, but qualitatively comparable to the value predicted by Tornatore and collaborators. Figures 2-8, and 12 are available in electronic form at http://www.aanda.orgBased on data obtained with the European Southern Observatory Very Large Telescope, Paranal, Chile, under Large Programs 070.A-9007 and 177.A-0837. Based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT) which is operated by the National Research Council (NRC) of Canada, the Institut National des Sciences de l'Univers of the Centre National de la Recherche

  15. Six-fold Coordinated Carbon Dioxide VI

    Energy Technology Data Exchange (ETDEWEB)

    Iota, V; Yoo, C; Klepeis, J; Jenei, Z

    2006-03-01

    Under standard conditions, carbon dioxide (CO{sub 2}) is a simple molecular gas and an important atmospheric constituent while silicon dioxide (SiO{sub 2}) is a covalent solid, and represents one of the fundamental minerals of the planet. The remarkable dissimilarity between these two group IV oxides is diminished at higher pressures and temperatures as CO{sub 2} transforms to a series of solid phases, from simple molecular to a fully covalent extended-solid V, structurally analogous to SiO{sub 2} tridymite. Here, we present the discovery of a new extended-solid phase of carbon dioxide (CO{sub 2}): a six-fold coordinated stishovite-like phase VI, obtained by isothermal compression of associated CO{sub 2}-II above 50GPa at 530-650K. Together with the previously reported CO{sub 2}-V and a-carbonia, this new extended phase indicates a fundamental similarity between CO{sub 2}--a prototypical molecular solid, and SiO{sub 2}--one of Earth's fundamental building blocks. The phase diagram suggests a limited stability domain for molecular CO{sub 2}-I, and proposes that the conversion to extended-network solids above 40-50 GPa occurs via intermediate phases II, III, and IV. The crystal structure of phase VI suggests strong disorder along the caxis in stishovite-like P4{sub 2}/mnm, with carbon atoms manifesting an average six-fold coordination within the framework of sp{sup 3} hybridization.

  16. Risk factors for Type II diabetes and diabetic retinopathy in a mexican-american population: Proyecto VER.

    Science.gov (United States)

    West, Sheila K; Munoz, Beatriz; Klein, Ronald; Broman, Aimee T; Sanchez, Rosario; Rodriguez, Jorge; Snyder, Robert

    2002-09-01

    Risk factors for type II diabetes and diabetic retinopathy were determined in a population-based study of Mexican-Americans. Proyecto VER (Vision, Evaluation, and Research) is a cross-sectional study in a random sample of the self-described Hispanic populations in Tucson and Nogales, Arizona, age 40 and older. Of 6,659 eligible subjects, 4,774 (72%) participated in the home questionnaire and clinic visit. Diabetes was defined as self-report of a physician diagnosis or hemoglobin A(1c) value of > or = 7.0%. Only type II diabetes was included. Diabetic retinopathy was assessed on stereo fundus photographs of all persons with diabetes. Questions were asked about demographic, personal, socioeconomic, and diabetes related variables. 1023 (21.4%) of the sample had type II diabetes, and 68% were in the low-income group (annual income less than $20,000). Diabetes was associated with Native-American ancestry, higher acculturation, low income, less education, and increasing body mass index after age and gender adjustment. Persons with previously undiscovered diabetes were more likely to have no regular source of care, no insurance, and currently smoke compared with persons with known diabetes. Only low income was related to proliferative retinopathy, once adjusted for other factors (odds ratio [OR] = 3.93, 95%, confidence limitations [CL] = 1.31-11.80). Several socioeconomic and other factors were associated with diabetes, but few were related to diabetic retinopathy. Persons in the low-income group appeared to be at greater risk of diabetes and the ocular complications of diabetes compared with those with more income. Further longitudinal studies in this population are needed to confirm the associations.

  17. Selection Component Analysis of Natural Polymorphisms using Population Samples Including Mother-Offspring Combinations, II

    DEFF Research Database (Denmark)

    Jarmer, Hanne Østergaard; Christiansen, Freddy Bugge

    1981-01-01

    Population samples including mother-offspring combinations provide information on the selection components: zygotic selection, sexual selection, gametic seletion and fecundity selection, on the mating pattern, and on the deviation from linkage equilibrium among the loci studied. The theory...

  18. The role of iron chelators and oxygen in the reduced nicotinamide adenine dinucleotide phosphate-cytochrome P450 oxidoreductase-dependent chromium(VI) reduction.

    Science.gov (United States)

    Mikalsen, A; Capellmann, M; Alexander, J

    1995-03-01

    Chromium(VI) reduction was studied in a system composed of reduced nicotinamide adenine dinucleotide phosphate-cytochrome P450 oxidoreductase (NADPH-P450 reductase) and different iron chelators and iron sources. In an aerobic phosphate buffer containing iron(II), chromium(VI) was not reduced by the Fe2+ probably because of spontaneous autoxidation of Fe2+, but freshly made Fe2+, added directly to a CrVI-containing buffer, reduced CrVI. Under anaerobic conditions, iron(II) reduced chromium(VI) stoichiometrically. A systemic containing ethylenediaminetetraacetic acid (EDTA)-Fe3+, NADPH-P450 reductase and NADPH effectively reduced chromium(VI) anaerobically. Under aerobic conditions this reaction was inhibited by about 45%. Adenosine diphosphate (ADP)-Fe3+, which is a poor acceptor of electrons from NADPH-P450 reductase, reduced chromium(VI) only marginally, Mannitol slightly increased the aerobic CrVI reduction. Addition of superoxide dismutase and catalase, which both regenerate some O2, led to inhibition of CrVI reduction. Ferritin, NADPH-P450 reductase and the iron chelators, EDTA and citrate, reduced CrVI, indicating mobilization of Fe2+ from ferritin. Low levels of EDTA (55 mumol l-1) and citrate (100 mumol l-1) in contrast to high levels (5 mmol l-1) did not increase CrVI reduction in microsomes. Using 4-(2-hydroxyethyl)-1-piperazineethane sulfonic acid buffer instead of phosphate buffer, the CrVI-reducing activity was increased.

  19. Bayesian and Non–Bayesian Estimation for Two Generalized Exponential Populations Under Joint Type II Censored Scheme

    Directory of Open Access Journals (Sweden)

    Samir Kamel Ashour

    2014-05-01

    Full Text Available In this paper, Bayesian and non-Bayesian estimators have been obtained for two generalized exponential populations under joint type II censored scheme, which generalize results of Balakrishnan and Rasouli (2008 and Shafay et al. (2013. The maximum likelihood estimators (MLEs of the parameters and Bayes estimators have been developed under squared error loss function as well as under LINEX loss function. Moreover, approximate confidence region are also discussed and compared with two Bootstrap confidence regions. Also the MLE and three confidence intervals for the stress–strength parameter  are explored. A numerical illustration for these new results is given. 

  20. VI Tallinna arhitektuuritriennaal / Leonhard Lapin

    Index Scriptorium Estoniae

    Lapin, Leonhard, 1947-

    2005-01-01

    15.-17. IX Tallinnas Niguliste kirikus toimuval VI Tallinna arhitektuuritriennaalil esinevad inglise arhitektuurikriitik Peter Davey, šveitsi arhitekt Peter Zumthor, soome arhitekt Juha Leviskä, eesti arhitekt Vilen Künnapu, eesti kunstiajaloolane Juhan Maiste jt. Külastatakse KUMU, tutvutab autor Pekka Vapaavuori

  1. (VI) oxide in acetic acid

    African Journals Online (AJOL)

    The oxidation of cyclohexene by chromium (VI) oxide in aqueous and acetic media was studied. The reaction products were analysed using infra red (IR) and gas chromatography coupled with mass (GC/MS) spectroscopy. The major products of the oxidation reaction in acetic acid medium were cyclohexanol, ...

  2. HLA Class I and Class II Alleles and Haplotypes Confirm the Berber Origin of the Present Day Tunisian Population.

    Directory of Open Access Journals (Sweden)

    Abdelhafidh Hajjej

    Full Text Available In view of its distinct geographical location and relatively small area, Tunisia witnessed the presence of many civilizations and ethnic groups throughout history, thereby questioning the origin of present-day Tunisian population. We investigated HLA class I and class II gene profiles in Tunisians, and compared this profile with those of Mediterranean and Sub-Sahara African populations. A total of 376 unrelated Tunisian individuals of both genders were genotyped for HLA class I (A, B and class II (DRB1, DQB1, using reverse dot-blot hybridization (PCR-SSO method. Statistical analysis was performed using Arlequin software. Phylogenetic trees were constructed by DISPAN software, and correspondence analysis was carried out by VISTA software. One hundred fifty-three HLA alleles were identified in the studied sample, which comprised 41, 50, 40 and 22 alleles at HLA-A,-B,-DRB1 and -DQB1 loci, respectively. The most frequent alleles were HLA-A*02:01 (16.76%, HLA-B*44:02/03 (17.82%, HLA-DRB1*07:01 (19.02%, and HLA-DQB1*03:01 (17.95%. Four-locus haplotype analysis identified HLA-A*02:01-B*50:01-DRB1*07:01-DQB1*02:02 (2.2% as the common haplotype in Tunisians. Compared to other nearby populations, Tunisians appear to be genetically related to Western Mediterranean population, in particular North Africans and Berbers. In conclusion, HLA genotype results indicate that Tunisians are related to present-day North Africans, Berbers and to Iberians, but not to Eastern Arabs (Palestinians, Jordanians and Lebanese. This suggests that the genetic contribution of Arab invasion of 7th-11th century A.D. had little impact of the North African gene pool.

  3. 29 CFR 1926.1126 - Chromium (VI).

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Chromium (VI). 1926.1126 Section 1926.1126 Labor... Chromium (VI). (a) Scope. (1) This standard applies to occupational exposures to chromium (VI) in all forms... objective data demonstrating that a material containing chromium or a specific process, operation, or...

  4. 29 CFR 1915.1026 - Chromium (VI).

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Chromium (VI). 1915.1026 Section 1915.1026 Labor... § 1915.1026 Chromium (VI). (a) Scope. (1) This standard applies to occupational exposures to chromium (VI... cement; or (4) Where the employer has objective data demonstrating that a material containing chromium or...

  5. Modelling Cr(VI) removal by a combined carbon-activated sludge system

    Energy Technology Data Exchange (ETDEWEB)

    Orozco, A. Micaela Ferro [Centro de Investigacion y Desarrollo en Criotecnologia de Alimentos (CIDCA), CONICET, Fac. de Cs. Exactas, UNLP. 47 y 116 (B1900AJJ), La Plata (Argentina); Contreras, Edgardo M. [Centro de Investigacion y Desarrollo en Criotecnologia de Alimentos (CIDCA), CONICET, Fac. de Cs. Exactas, UNLP. 47 y 116 (B1900AJJ), La Plata (Argentina)], E-mail: econtrer@quimica.unlp.edu.ar; Zaritzky, Noemi E. [Centro de Investigacion y Desarrollo en Criotecnologia de Alimentos (CIDCA), CONICET, Fac. de Cs. Exactas, UNLP. 47 y 116 (B1900AJJ), La Plata (Argentina); Fac. de Ingenieria, UNLP. 47 y 1 (B1900AJJ), La Plata (Argentina)

    2008-01-15

    The combined carbon-activated sludge process has been proposed as an alternative to protect the biomass against toxic substances in wastewaters; however, the information about the effect of powdered-activated carbon (PAC) addition in activated sludge reactors for the treatment of wastewaters containing Cr(VI) is limited. The objectives of the present study were: (a) to evaluate the removal of hexavalent chromium by (i) activated sludge microorganisms in aerobic batch reactors, (ii) powdered-activated carbon, and (iii) the combined action of powdered-activated carbon and biomass; (b) to propose mathematical models that interpret the experimental results. Different Cr(VI) removal systems were tested: (S1) biomass (activated sludge), (S2) PAC, and (S3) the combined activated carbon-biomass system. A Monod-based mathematical model was used to describe the kinetics of Cr(VI) removal in the system S1. A first-order kinetics with respect to Cr(VI) and PAC respectively, was proposed to model the removal of Cr(VI) in the system S2. Cr(VI) removal in the combined carbon-biomass system (S3) was faster than both Cr(VI) removal using PAC or activated sludge individually. Results showed that the removal of Cr(VI) using the activated carbon-biomass system (S3) was adequately described by combining the kinetic equations proposed for the systems S1 and S2.

  6. Therapeutic songwriting in music therapy, Part II: Comparing the literature with practice across diverse clinical populations

    DEFF Research Database (Denmark)

    Baker, Felicity; Wigram, Tony; Stott, Dave

    2009-01-01

    . Responses to a 21-question on-line survey were obtained from 419 professional music therapists practicing in 29 countries which focused on approaches to songwriting within their practice with a single clinical population. Results suggest that in general, the literature provides good representation for what......  A growing body of literature on therapeutic songwriting with diverse clinical populations indicates that clinicians employ a wide range of approaches. The purpose of this research was to establish trends in the clinical practice of songwriting as implemented across a range of clinical populations......, and the types of allied health professionals involved in the songwriting interventions. There is a distinct absence of songwriting literature as applied in developmental disability, autism spectrum disorder, and aged care contexts so the resulting practice trends offered here contribute to the increasing body...

  7. Status report on the National Research Council`s BEIR VI study

    Energy Technology Data Exchange (ETDEWEB)

    Douple, E.

    1995-10-01

    The objectives of the committee on Biological Radiation Effects of Ionizing Radiation VI (BEIR) are to : assist the EPA in phase I by collecting and evaluating information on ongoing studies and results of studies published since the BEIR VI report of 1988 on the health effects of exposure to radon progeny; to perform a full scale reassessment of the health effects if a phase II study is warranted on the basis of phase I results. The BEIR VI working groups consists of miner data sets and analysis; residential studies; smoking and nonsmoking interactions; exposure and dosimetry; cellular and molecular studies; risk models and uncertainties; and animal studies.

  8. Human Leukocyte Antigen Class II Alleles Are Associated with Hepatitis C Virus Natural Susceptibility in the Chinese Population

    Directory of Open Access Journals (Sweden)

    Ming Yue

    2015-07-01

    Full Text Available Human leukocyte antigen (HLA class II molecule influences host antigen presentation and anti-viral immune response. The aim of this study was to investigate whether single nucleotide polymorphisms (SNPs within HLA class II gene were associated with different clinical outcomes of hepatitis C virus (HCV infection. Three HLA class II SNPs (rs3077, rs2395309 and rs2856718 were genotyped by TaqMan assay among Chinese population, including 350 persistent HCV infection patients, 194 spontaneous viral clearance subjects and 973 HCV-uninfected control subjects. After logistic regression analysis, the results indicated that the rs2856718 TC genotype was significantly associated with the protective effect of the HCV natural susceptibility (adjusted OR: 0.712, 95% CI: 0.554–0.914 when compared with reference TT genotype, and this remained significant after false discovery rate (FDR correction (p = 0.024. Moreover, the protective effect of rs2856718 was observed in dominant genetic models (adjusted OR: 0.726, 95% CI: 0.574–0.920, and this remained significant after FDR correction (p = 0.024. In stratified analysis, a significant decreased risk was found in rs2856718C allele in the male subgroup (adjusted OR: 0.778, 95% CI: 0.627–0.966 and hemodialysis subgroup (adjusted OR: 0.713, 95% CI: 0.552–0.921. Our results indicated that the genetic variations of rs2856718 within the HLA-DQ gene are associated with the natural susceptibility to HCV infection among the Chinese population.

  9. Comparison of physical and mental health status between cancer survivors and the general population: a Korean population-based survey (KNHANES II-IV).

    Science.gov (United States)

    Kim, Kyae Hyung; Cho, Young Youn; Shin, Dong Wook; Lee, Ju Hyun; Ko, Young-Jin; Park, Sang Min

    2013-12-01

    To compare the physical and mental health status of the general population with that of cancer survivors in South Korea. We analyzed 19,035 subjects (age ≥40 years), who participated in the 2001-2009 Korea National Health and Nutrition Examination Survey II-IV. We compared metabolic syndrome components, health behaviors, and mental health outcomes between cancer survivors and non-cancer controls. Cancer survivors accounted for 1.68 % (n = 316) of total population. Cancer survivors did not show low occurrence of hypertension and diabetes compared to the control group. Both cancer survivors and the general population had high risks of physical inactivity (75.4 % and 75.5 %, respectively) and inadequate sleep (52.5 % and 60.7 %, respectively). In the unadjusted model, depression was more common in cancer survivors (odds ratio [OR], 1.61; 95 % CI, 1.22-2.74), so was suicidal ideation (OR, 1.51; 95 % CI, 0.16-1.96) than non-cancer controls. After adjustment for attributable socioeconomic factors, the elevated adjusted odds ratios (aORs) among cancer survivors were reduced by 23 % in depression and 45 % in suicidal thought. Cancer survivors at physical and mental health of South Korean cancer survivors was not optimal. Their control rates of modifiable risk factors were similar or even lower than those for the non-cancer groups. Depression was highly prevalent in cancer survivors which can be ascribed, at least in part, to socioeconomic environment. A better-targeted intervention to improve the health of this population may be needed.

  10. 76 FR 56982 - Announcement of Federal Underground Injection Control (UIC) Class VI Program for Carbon Dioxide (CO2

    Science.gov (United States)

    2011-09-15

    ... governments. Private Owners or Operators of CO2 injection wells used for Class VI GS. Private Owners or Operators of existing CO2 injection wells transitioning from Class I, II, or Class V injection activities to...

  11. Results of Expedicion Humana. II. Analysis of HLA class II alleles in three African American populations from Colombia using the PCR/SSOP: identification of a novel DQB1*02 (*0203) allele.

    Science.gov (United States)

    Trachtenberg, E A; Keyeux, G; Bernal, J; Noble, J A; Erlich, H A

    1996-09-01

    PCR/SSOP typing methods were used to analyze the HLA Class II DRB1, DQA1, DQB1 and DPB1 loci of samples from three African American populations of Colombia. Forty samples from the Cauca (Pacific), and twenty samples each from the Choco (North Pacific Coast) and the Providencia (Caribbean island) populations, were collected and the Class II loci analyzed under the auspices of the Expedicion Humana. Despite the limited number of samples analyzed, the African Colombian populations exhibit a very high degree of class II polymorphism. A great diversity of DRB1 alleles was found, with representatives from all serological classes, including 19 DRB1 alleles in the Providencia, 16 in the Cauca and 14 in the Choco groups. In addition, a novel DQB1*02 allele (*0203) was found in two individuals from the Cauca population of the Pacific Coast. The sequence of the DQB1*0203 allele, associated with DR3, differs from DQB1*0201 by only one nucleotide substitution (C-->A) in the second position of codon 57, resulting in an Ala to Asp change. The addition of DQB1*0203 brings the total number of DQB1 alleles identified to date to 26. HLA class II diversity is much greater in these African Colombian populations than that seen in nearby Amerindian populations. Analysis of regional Colombian African American HLA population genetics is discussed with respect to the Colombian Amerindian HLA genetics described in an accompanying paper.

  12. Molecular typing of HLA class II antigens in a São Paulo population

    Directory of Open Access Journals (Sweden)

    Goldberg A.C.

    1998-01-01

    Full Text Available In the present paper we show data obtained from a normal population with a racially mixed profile typical of the city of São Paulo, State of São Paulo. Data were generated with polymerase chain reaction using sequence specific primers (PCR-SSP for HLA-DRB and polymerase chain reaction followed by hybridization with sequence specific oligonucleotide probes (PCR-SSO for HLA-DQA1 and HLA-DQB1 loci. HLA-DRB, DQA1, DQB1 and haplotype frequencies as well as common linkage disequilibria were found. This population was also shown to be in genetic equilibrium according to the Hardy-Weinberg law. HLA-DR typing of a normal sample from the city of Porto Velho, State of Rondonia, highlighted the importance of different sets of HLA profiles found in other regions of the country. This database provides essential information for screening studies of disease associations, forensic analyses and transplants.

  13. Hvad bruger vi tiden til?

    DEFF Research Database (Denmark)

    Brichet, Nathalia Sofie; Hastrup, Frida

    2016-01-01

    I denne artikel kaster vi et antropologisk blik på samtidsarkæologi ved at diskutere måder, hvorpå antropologiske analyser kan adressere tid, fortidige hændelser og historiske processer. Vi argumenterer for, at en radikal nutidsorientering er en afgørende kvalitet ved det antropologiske feltarbej...... komplicerer en ide om fortidige (gamle eller nyere) objekter som nogle, der kan udgraves......., hvis sigte det er løbende at generere sit materiale nu og her med henblik på at skabe nye forståelser, historier og forslag til mangeartede sammenhænge. En implikation af dette er, at uanset hvor ’historisk’ et antropologisk materiale end måtte være, må det altid ses som samtidigt og ufærdigt, hvilket...

  14. Angiotensin II receptor blockers and risk of acute pancreatitis - a population based case-control study in Sweden.

    Science.gov (United States)

    Bexelius, Tomas S; Ljung, Rickard; Mattsson, Fredrik; Lu, Yunxia; Lindblad, Mats

    2017-03-07

    Acute pancreatitis is a potentially lethal disease, with a rising incidence in the Western world. Yet, no pharmacological prevention or specific treatment for acute pancreatitis exists. Also, the connection with severity of acute pancreatitis is unknown. Experimental and epidemiological research suggests a protective effect of angiotensin II receptor blockers. During 2006 to 2008, we performed a nationwide case-control study on Swedish residents aged 40-84 years. First-time cases with acute pancreatitis were identified in the National Patient Register and data on dispensed prescriptions was retrieved from the Prescribed Drug Register. Controls were randomly selected from the general population in Sweden frequency-matched on sex, age, and calendar year. To estimate relative risk of acute pancreatitis, by degree of severity, among users of angiotensin II receptor blockers, as compared to non-users, we used multivariable logistic regression analysis to calculate odds ratios (OR) with 95% confidence interval (CI). Among 6,161 cases of acute pancreatitis and 61,637 controls, current use of angiotensin II receptor blockers was followed by a decreased risk of acute pancreatitis, compared to non-users, adjusted OR 0 · 77 (95% CI 0 · 69-0 · 86). No protective association, but an increased risk was found for users of angiotensin-converting enzyme inhibitors (adjusted OR 1 · 11, 95% CI: 1 · 01-1 · 21), analysed for comparison reasons. There was a significant decreased risk associated with both severe acute pancreatitis, (OR 0 · 71 (0 · 59-0 · 85), and mild acute pancreatitis; adjusted OR 0 · 81 (0 · 70-0 · 94). This population-based case-control study indicates that use of angiotensin II receptor blockers might be associated with a lesser risk of acute pancreatitis, and that the protective association was significant among cases of both severe and mild acute pancreatitis.

  15. The Ability of Benzoic Acid to Reduce Cr(VI Heavy Metal Content in Aqueous Solution

    Directory of Open Access Journals (Sweden)

    Anugrah Windy Mustikarini

    2015-12-01

    Full Text Available Chromium (VI is an ionic heavy metal which has to be handled properly when dissolved in water due to its toxicity, corosive, carsinogenic activity.. According to the State Minister for Population and Environment’s regulation, the quality standards of waste water, which is allowed to be discharge on surface water contains Cr(VI is 0.05-1 mg/L. This research used benzoic acid which is a kind of organic acid to reduce Cr(VI content in water. Benzoic acid has an active carboxyl group which interact this metal. This paper, the elimination of Cr(VI using benzoic acid is undertaken through pH adjustment by regulating with phosphoric acid. The result showed the best condition to reducing Cr(VI content 41.99% when 400 ppm of benzoic acid and pH 7 was applied, respectively.

  16. Nitrate Enhanced Microbial Cr(VI) Reduction-Final Report

    Energy Technology Data Exchange (ETDEWEB)

    John F. Stolz

    2011-06-15

    proteins (Gmet_2478 and Gmet_1641) were up-regulated with exposure to Cr(VI). A nine-heme cytochrome C was purified that could reduce nitrite and could be oxidized by Cr(VI). For D. desulfuricans, we found that confirmed that Cr(VI) induced a prolonged lag period when Cr(VI) was reduced. Over three hundred proteins were unequivocally identified by LC/MS-MS and a significant number of down-regulated proteins for which the levels were changed >2 fold compared to control. Sulfite reductase levels were similar, however, nitrate and nitrite reductase were down-regulated. The supernatant of spent cultures was found to contain a filterable, heat stable compound that rapidly reduced Cr(VI). In addition, desulfoviridin was purified from nitrate grown cells and shown to have nitrite reductase activity that was inhibited by Cr(VI). For S. barnesii, periplasmic nitrate reductase (Nap), nitrite reductase (Nrf), and the metalloid reductase (Rar) were purified and characterized. The supernatant of spent cultures was also found to contain a filterable, heat stable compound that rapidly reduced Cr(VI) but that Rar also reduced Cr(VI). Our results from specific aims 1 through 3 indicate that for G. metallireducens, Cr(VI) inhibits nitrate respiration as it oxidizes cytochromes involved in nitrate respiration. Iron reduction is apparently not affected and the inhibitory affects of Cr(VI) may be attenuated by the addition of sufficient Fe(III) to generate Fe(II) that abiotically reduces the chromium. For S. barnesii, although the enzyme assays indicate that the components of the respiratory pathway for nitrate (e.g. Nap and Nrf) are inhibited by chromate, the organism has a mechanism to prevent this from actually occurring. Our current hypothesis is that the non-specific metalloid reductase (Rar) is providing resistance by reducing the Cr(VI). The strategy here would be to enhance its growth and metabolism in the natural setting. Lactate is a suitable electron donor for S. barnesii but other

  17. The performance of SAPS II in a cohort of patients admitted to 99 Italian ICUs: results from GiViTI. Gruppo Italiano per la Valutazione degli interventi in Terapia Intensiva.

    Science.gov (United States)

    Apolone, G; Bertolini, G; D'Amico, R; Iapichino, G; Cattaneo, A; De Salvo, G; Melotti, R M

    1996-12-01

    To assess the validity of SAPS II (new Simplified Acute Physiology Score) in a cohort of patients admitted to a large sample of Italian intensive care units (ICU). The ability of the SAPS II scoring system to predict the probability of hospital mortality was assessed with calibration and discrimination measures obtained using published coefficients. A new logistic regression equation was then developed and further formal calibration and discrimination measures were estimated for the customized model. From the 2202 consecutive patients recruited during a 1-month period in 99 ICUs, a total of 1393 patients were included in this validation study. When the parameters based on the standard model were applied, the expected probability of mortality did not fit those actually observed in the cohort (p < 0.001), although it showed satisfactory discrimination (area under the receiver operating characteristic curve = 0.80). Such lack of fit yields an overall under prediction of mortality (observed/expected ratio = 1.14) that reflects a uniform pattern across a preselected set of subgroups. Customization allowed new mortality estimates to be calculated, with satisfactory calibration (p = 0.82) and a more uniform pattern across subgroups. SAPS II maintained its validity in an independent sample of patients recruited in a large network of Italian ICUs only after appropriate adaptation (first-level customization). Whether the determinants of this relatively poor performance are related to differences in unmeasured case-mix, methods of application, or quality of care delivered is a matter for discussion that cannot be solved with the data presently available. However, these findings suggest that caution is warranted before implementing the standard SAPS II scoring system parameters outside formal research projects.

  18. Fibromyalgia in the adult Danish population: II. A study of clinical features

    DEFF Research Database (Denmark)

    Prescott, E; Jacobsen, S; Kjøller, M

    1993-01-01

    Clinical characteristics of fibromyalgia have so far been based mainly on patients identified in rheumatologic settings. This paper offers the clinical findings in fibromyalgia based on a national health interview survey, in which 123 persons fulfilled preset criteria for widespread pain. Clinical......, headache, difficulty in stair-climbing, and poorer self-evaluated health with more tender points was found. Contrary to that which was expected, fibromyalgia subjects did not suffer from sleep disturbances, irritable bowels or morning stiffness. Our findings indicate that clinical characteristics...... of fibromyalgia in the general population may differ from those found in rheumatological settings....

  19. Selective adsorption of Cr(VI) ions from aqueous solutions using Cr(6+)-imprinted Pebax/chitosan/GO/APTES nanofibrous adsorbent.

    Science.gov (United States)

    Etemadi, Mohammadmahdi; Samadi, Saman; Yazd, Shabnam Sharif; Jafari, Pooya; Yousefi, Negin; Aliabadi, Majid

    2017-02-01

    In the present study, a novel Cr(6+)-imprinted Pebax/chitosan/GO/APTES nanofibrous adsorbent (Cr(6+)-PCGA) was prepared and its performance was compared with PCGA nanofibers for selective sorption of Cr(VI) ions from aqueous solutions. The prepared nanofibers were characterized using FTIR, SEM and EDAX analysis. The influence of batch sorption experiments including GO/APTES content, pH, contact time, Cr(VI) initial concentration and temperature on the Cr(VI) sorption efficiency using synthesized nanofibers was investigated. The Cr(VI) sorption data were well described using pseudo-second-order kinetic and Redlich-Peterson isotherm models. The maximum sorption capacities of Cr(6+)-PCGA and PCGA nanofibers for Cr(VI) ions sorption were found to be 204.5 and 550.5mgg(-1), respectively. Thermodynamic studies indicated an endothermic and spontaneous nature of Cr(VI) ions sorption using both Cr(6+)-PCGA and PCGA nanofibers. The selectivity coefficient values of Cr(VI)/Pb(II), Cr(VI)/Cu(II) and Cr(VI)/Ni(II) indicated the higher selectivity of Cr(6+)-PCGA nanofibrous adsorbent for Cr(VI) ions separation compared to PCGA nanofibers. The good stability and reusability of Cr(6+)-PCGA nanofibrous adsorbent for five sorption/desorption cycles promised a higher potential of ion-imprinted nanofibers for separation of metal ions from aqueous systems in a large scale. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Estimated dietary intakes and sources of flavanols in the German population (German National Nutrition Survey II).

    Science.gov (United States)

    Vogiatzoglou, Anna; Heuer, Thorsten; Mulligan, Angela A; Lentjes, Marleen A H; Luben, Robert N; Kuhnle, Gunter G C

    2014-01-01

    Data from intervention studies suggest a beneficial effect of flavanols on vascular health. However, insufficient data on their intake have delayed the assessment of their health benefits. The aim of this study was to estimate intake of flavanols and their main sources among people living in Germany. Data from diet history interviews of the German National Nutrition Survey II for 15,371 people across Germany aged 14-80 years were analyzed. The FLAVIOLA Flavanol Food Composition Database was compiled using the latest US Department of Agriculture and Phenol-Explorer Databases and expanded to include recipes and retention factors. Mean intake of total flavanols, flavan-3-ol monomers, proanthocyanidins (PA), and theaflavins in Germany was 386, 120, 196, and 70 mg/day, respectively. Women had higher intakes of total flavanols (399 mg/day) than men (372 mg/day) in all age groups, with the exception of the elderly. Similar results were observed for monomers (108 mg/day for men, 131 mg/day for women) and PA (190 mg/day; 203 mg/day), although intake of theaflavins was higher in men (74 mg/day; 66 mg/day). There was an age gradient with an increase in total flavanols, monomers, and theaflavins across the age groups. The major contributor of total flavanols in all subjects was pome fruits (27%) followed by black tea (25%). This study demonstrated age- and sex-related variations in the intake and sources of dietary flavanols in Germany. The current analysis will provide a valuable tool in clarifying and confirming the potential health benefits of flavanols.

  1. Validated Competing Event Model for the Stage I-II Endometrial Cancer Population

    Energy Technology Data Exchange (ETDEWEB)

    Carmona, Ruben; Gulaya, Sachin; Murphy, James D. [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States); Rose, Brent S. [Harvard Radiation Oncology Program, Harvard Medical School, Boston, Massachusetts (United States); Wu, John; Noticewala, Sonal [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States); McHale, Michael T. [Department of Reproductive Medicine, Division of Gynecologic Oncology, University of California San Diego, La Jolla, California (United States); Yashar, Catheryn M. [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States); Vaida, Florin [Department of Family and Preventive Medicine, Biostatistics and Bioinformatics, University of California San Diego Medical Center, San Diego, California (United States); Mell, Loren K., E-mail: lmell@ucsd.edu [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States)

    2014-07-15

    Purpose/Objectives(s): Early-stage endometrial cancer patients are at higher risk of noncancer mortality than of cancer mortality. Competing event models incorporating comorbidity could help identify women most likely to benefit from treatment intensification. Methods and Materials: 67,397 women with stage I-II endometrioid adenocarcinoma after total hysterectomy diagnosed from 1988 to 2009 were identified in Surveillance, Epidemiology, and End Results (SEER) and linked SEER-Medicare databases. Using demographic and clinical information, including comorbidity, we sought to develop and validate a risk score to predict the incidence of competing mortality. Results: In the validation cohort, increasing competing mortality risk score was associated with increased risk of noncancer mortality (subdistribution hazard ratio [SDHR], 1.92; 95% confidence interval [CI], 1.60-2.30) and decreased risk of endometrial cancer mortality (SDHR, 0.61; 95% CI, 0.55-0.78). Controlling for other variables, Charlson Comorbidity Index (CCI) = 1 (SDHR, 1.62; 95% CI, 1.45-1.82) and CCI >1 (SDHR, 3.31; 95% CI, 2.74-4.01) were associated with increased risk of noncancer mortality. The 10-year cumulative incidences of competing mortality within low-, medium-, and high-risk strata were 27.3% (95% CI, 25.2%-29.4%), 34.6% (95% CI, 32.5%-36.7%), and 50.3% (95% CI, 48.2%-52.6%), respectively. With increasing competing mortality risk score, we observed a significant decline in omega (ω), indicating a diminishing likelihood of benefit from treatment intensification. Conclusion: Comorbidity and other factors influence the risk of competing mortality among patients with early-stage endometrial cancer. Competing event models could improve our ability to identify patients likely to benefit from treatment intensification.

  2. Statistics of Natural Populations. II. Estimating an Allele Probability in Families Descended from Cryptic Mothers.

    Science.gov (United States)

    Arnold, J; Morrison, M L

    1985-04-01

    In population studies, adults are frequently difficult or inconvenient to identify for genotype, but a family profile of genotypes can be obtained from an unidentified female crossed with a single unidentified male. The problem is to estimate an allele frequency in the cryptic parental gene pool from the observed family profiles. For example, a worker may wish to estimate inversion frequencies in Drosophila; inversion karyotypes are cryptic in adults but visible in salivary gland squashes from larvae. A simple mixture model, which assumes the Hardy-Weinberg law, Mendelian laws and a single randomly chosen mate per female, provides the vehicle for studying three competing estimators of an allele frequency. A simple, heuristically appealing estimator called the Dobzhansky estimator is compared with the maximum likelihood estimator and a close relative called the grouped profiles estimator. The Dobzhansky estimator is computationally simple, consistent and highly efficient and is recommended in practice over its competitors.

  3. Current range of the eastern population of Painted Bunting (Passerina ciris). Part II: Winter range

    Science.gov (United States)

    Sykes, P.W.; Holzman, S.; Iñigo-Elias, Eduardo E.

    2007-01-01

    The importance of wintering areas for Neotropical migrants is well established. The wintering range of the eastern population of Painted Bunting (Passerina ciris) is described in detail and presented in maps. The paper also discusses extralimital records from islands in the Caribbean Basin as well as scattered wintering individuals outside the winter range. The possibility of eastern birds wintering on the Yucatan Peninsula and adjacent Central America is considered. An extensive treatment of the protected areas of Peninsular Florida, the northern Bahamas, and Cuba describes the importance of upland habitats within these protected areas for wintering buntings. This information should be useful to land management agencies, conservation organizations, and private landholders for the welfare of the bunting and biodiversity in general and may also be of interest to ornithologists, other biological disciplines, naturalists, and birders.

  4. [Simultaneous remediation of Cr (VI) and p-NCB by nanosacle iron].

    Science.gov (United States)

    Niu, Shao-feng; Li, Chun-hui; Lou, Zhang-hua; Xu, Yue-ping

    2009-01-01

    Nanoscale Fe and Ni/Fe, which were prepared by chemical deposition, were utilized as catalyst for remediation of Cr(VI) and pNCB in contaminated water. The interactions between Cr( VI) and p-NCB in contaminated water during the simultaneous remediation process were analyzed. It is demonstrated from the experiment that p-NCB can be degradated into p-CAN by nanoscale iron, but cannot exhibit the effect of dechlorination, and that there is a competitive relationship between Cr( VI) and p-NCB in the remediation process. The nanoscale Nil Fe bimetals could be applied in simultaneous remediation of p-NCB with Cr( VI) and give rise to a good remediation efficiency, where the products are only Cr(III) and p-CAN without any intermediate products. It was found that the conditions of higher Ni(II) concentration can promote the degradation rate of p-NCB. The optimum Ni/Fe ratio is 1:50. Whereas, the higher concentrations of Cr(VI) and p-NCB will lead to the lower degradation rate. Under the condition that concentration of Cr (VI) was 20 mg/L, the corresponding maximum dechlorination of p-NCB was 43.0%; under the condition that concentration of p-NCB was 40 mg/L, the corresponding maximum removal efficiency of Cr(VI) was 71.4%.

  5. Determination of chromium (VI) in primary and secondary fertilizer and their respective precursors.

    Science.gov (United States)

    Krüger, Oliver; Fiedler, Francesca; Adam, Christian; Vogel, Christian; Senz, Rainer

    2017-09-01

    Hexavalent chromium species (Cr(VI)) are often carcinogenic, of high acute toxicity, highly mobile, and thus pose a severe risk to health and environment. Fertilizers usually contain significant amounts of chromium. Therefore, a reliable analysis of chromium and the fraction of Cr(VI) are crucial for safe use of fertilizers. This problem is expected to increase in the future, since more and more recycled fertilizers emerge due to increasing fertilizer demand and respective supply risks. However, existing analytical methods have been developed for conventional fertilizers and have to be tested whether they are suitable for the new materials. Thus, we performed a wet-chemical extraction for Cr(VI) on several matrices as well as respective quality control experiments including spiking with Cr(III) and Cr(VI) compounds. We found the Cr(VI) amounts to be below 2 mg/kg except for a thermally post-treated sewage sludge ash (SSA) that showed 12.3 mg/kg. The presence of organic matter e.g. in sludge or precipitated struvite caused a reduction of spiked Cr(VI) and thus no satisfying recovery for quality control. Cr(VI) reduction was also observed for SSA, presumably due to the presence of Fe(II) compounds. Even though the tested procedure can be hampered in some recycled fertilizer matrices, it might be adapted to be applicable also for these complex samples. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Populism

    OpenAIRE

    Abts, Koenraad; Van Kessel, Stijn

    2015-01-01

    Populism is a concept applied to a wide range of political movements and actors across the globe. There is, at the same time, considerable confusion about the attributes and manifestation of populism, as well as its impact on democracy. This contribution identifies the defining elements of the populist ideology and discusses the varieties in which populism manifests itself, for instance as a component of certain party families. We finally discuss various normative interpretations of populism,...

  7. On the population of remnant Fanaroff-Riley type II radio galaxies and implications for radio source dynamics

    Science.gov (United States)

    Godfrey, L. E. H.; Morganti, R.; Brienza, M.

    2017-10-01

    The purpose of this work is two-fold: (1) to quantify the occurrence of ultrasteep spectrum remnant Fanaroff-Riley type II (FRII) radio galaxies in a 74 MHz flux-limited sample, and (2) perform Monte Carlo simulations of the population of active and remnant FRII radio galaxies to confront models of remnant lobe evolution, and to provide guidance for further investigation of remnant radio galaxies. We find that fewer than 2 per cent of FRII radio galaxies with S74 MHz > 1.5 Jy are candidate ultrasteep spectrum remnants, where we define ultrasteep spectrum as α _74 MHz^1400 MHz > 1.2. Our Monte Carlo simulations demonstrate that models involving Sedov-like expansion in the remnant phase, resulting in rapid adiabatic energy losses, are consistent with this upper limit, and predict the existence of nearly twice as many remnants with normal (not ultrasteep) spectra in the observed frequency range as there are ultrasteep spectrum remnants. This model also predicts an ultrasteep remnant fraction approaching 10 per cent at redshifts z studies of the remnant population.

  8. Har vi brug for hovedregning?

    DEFF Research Database (Denmark)

    Ejersbo, Lisser Rye

    2015-01-01

    Hvor ofte har vi brug for at regne noget i hoved? Har de fleste af os ikke altid et elektronisk hjælpemiddel ved hånden enten som en lille lommeregner eller telefonen? Selvom det umiddelbart kan synes unødvendigt at træne hovedregning, viser det sig, at netop træning af hovedregning støtter...... udvikling af hurtige regnestrategier, hvorfor det faktisk er en god ide at investere tid og energi i at træne netop dette....

  9. Type 1 Diabetes in the Spanish Population: additional factors to Class II HLA-DR3 and -DR4

    Directory of Open Access Journals (Sweden)

    Ibarra José M

    2005-04-01

    Full Text Available Abstract Background The Major Histocompatibility Complex is the main genetic contributor to susceptibility to type 1 diabetes (T1D; genome-wide scans have consistently mapped increased predisposition to this region. The highest disease risk has been associated with HLA-DR3 and HLA-DR4. In particular, the DR3-positive ancestral haplotype 18.2 was reported as highly diabetogenic. We aimed to corroborate whether this haplotype increases the susceptibility conferred by the DQ2-DR3 alleles in a Mediterranean population. We also searched for additional susceptibility factors to the classic DQ2-DR3 and DQ8-DR4. Results Genetic MHC markers were analysed in a case-control study with 302 T1D patients and 529 ethnically matched controls. DR3-TNFa1b5 carrier rate was significantly higher in DR3-positive heterozygous T1D patients than in DR3-positive heterozygous controls (p = 0.0019; odds ratio OR [95% confidence interval CI] = 2.26 [1.3–3.93]. This data was confirmed analysing the allelic frequency, which includes the information corresponding to the DR3-homozygous individuals (p = 0.001; OR = 2.09 and by using the Arlequin software to check the DR3-positive haplotypes (p = 0.004;OR = 1.93. The present results provide strong evidence of a second susceptibility region in the ancestral haplotype 18.2 in the Spanish population. Moreover, we searched for T1D susceptibility factors in addition to the MHC classical ones, within the DR2-DQ6/DR3-DQ2/DR4-DQ8 negative population. Several genetic markers in both MHC class II (DQA1*0101-DQB1*0501 [p = 0.007;OR = 2.81], DQA1*0201-DQB1*0202 [p = 0.03; OR = 2.35] and III (TNFa2b1 [p = 0.01 OR = 2.74], BAT-2*2 [p = 0.004; OR = 3.19] were found. These different alleles associated with T1D were not independent and we observed linkage disequilibrium among them leading us to describe two new risk haplotypes (DQA1*0101-DQB1*0501-TNFa2b1 and DQA1*0201-DQB1*0202- BAT-2*2. Finally, we studied a T1D susceptibility

  10. Integrated Ecogenomics Study for Bioremediation of Cr(VI) at Hanford 100H Area

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty, Romy; Chakraborty, Romy

    2008-08-12

    Hexavalent chromium is a widespread contaminant found in groundwater. In order to stimulate microbially mediated Cr(VI)-reduction, a poly-lactate compound was injected into Cr(VI)-contaminated aquifers at site 100H at Hanford. Investigation of bacterial community composition using high-density DNA microarray analysis of 16S rRNA gene products revealed a stimulation of Pseudomonas, Desulfovibrio and Geobacter species amongst others. Enrichment of these organisms coincided with continued Cr(VI) depletion. Functional gene-array analysis of DNA from monitoring well indicated high abundance of genes involved in nitrate-reduction, sulfate-reduction, iron-reduction, methanogenesis, chromium tolerance/reduction. Clone-library data revealed Psedomonas was the dominant genus in these samples. Based on above results, we conducted lab investigations to study the dominant anaerobic culturable microbial populations present at this site and their role in Cr(VI)-reduction. Enrichments using defined anaerobic media resulted in isolation of an iron-reducing, a sulfate-reducing and a nitrate-reducing isolate among several others. Preliminary 16S rDNA sequence analysis identified the isolates as Geobacter metallireducens, Pseudomonas stutzeri and Desulfovibrio vulgaris species respectively. The Pseudomonas isolate utilized acetate, lactate, glycerol and pyruvate as alternative carbon sources, and reduced Cr(VI). Anaerobic washed cell suspension of strain HLN reduced almost 95?M Cr(VI) within 4 hr. Further, with 100?M Cr(VI) as sole electron-acceptor, cells grew to 4.05 x 107 /ml over 24 h after an initial lag, demonstrating direct enzymatic Cr(VI) reduction coupled to growth. These results demonstrate that Cr(VI)-immobilization at Hanford 100H site could be mediated by direct microbial metabolism in addition to indirect chemical reduction of Cr(VI) by end-products of microbial activity.

  11. Simultaneously photocatalytic treatment of hexavalent chromium (Cr(VI)) and endocrine disrupting compounds (EDCs) using rotating reactor under solar irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Youngji [Korea Institute of Energy Research, New and Renewable Energy Research Division, Hydrogen Laboratory, 152 Gajeong-ro, Yuseong-gu, Daejeon 305-343 (Korea, Republic of); Yonsei University, Department of Chemical and Biomolecular Engineering, 134 Shinchon-dong, Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Joo, Hyunku [Korea Institute of Energy Research, New and Renewable Energy Research Division, Hydrogen Laboratory, 152 Gajeong-ro, Yuseong-gu, Daejeon 305-343 (Korea, Republic of); Her, Namguk [Korea Army Academy at Young-Cheon, Department of Chemistry and Environmental Science, 135-1 Changhari, Kokyungmeon, Young-cheon, Gyeongbuk 770-849 (Korea, Republic of); Yoon, Yeomin [University of South Carolina, Department of Civil and Environmental Engineering, Columbia, SC 29208 (United States); Sohn, Jinsik [Kookmin University, School of Civil and Environmental Engineering, 77 Jeongneung-ro, Seongbuk-gu, Seoul 136-702 (Korea, Republic of); Kim, Sungpyo [Korea University, Department of Environmental Engineering, Sejong 339-700 (Korea, Republic of); Yoon, Jaekyung, E-mail: jyoon@kier.re.kr [Korea Institute of Energy Research, New and Renewable Energy Research Division, Hydrogen Laboratory, 152 Gajeong-ro, Yuseong-gu, Daejeon 305-343 (Korea, Republic of)

    2015-05-15

    Highlights: • Self-rotating reactor including TiO{sub 2} NTs is applied under solar irradiation. • Simultaneously photocatalysis of Cr(VI) and EDCs is observed to be up to 95%. • Photocatalytic reactions of Cr(VI) and EDCs are favorable under acidic pH. • Charge interaction and hole scavenge between TiO{sub 2} and pollutants are synergy factors. - Abstract: In this study, simultaneous treatments, reduction of hexavalent chromium (Cr(VI)) and oxidation of endocrine disrupting compounds (EDCs), such as bisphenol A (BPA), 17α-ethinyl estradiol (EE2) and 17β-estradiol (E2), were investigated with a rotating photocatalytic reactor including TiO{sub 2} nanotubes formed on titanium mesh substrates under solar UV irradiation. In the laboratory tests with a rotating type I reactor, synergy effects of the simultaneous photocatalytic reduction and oxidation of inorganic (Cr(VI)) and organic (BPA) pollutants were achieved. Particularly, the concurrent photocatalytic reduction of Cr(VI) and oxidation of BPA was higher under acidic conditions. The enhanced reaction efficiency of both pollutants was attributed to a stronger charge interaction between TiO{sub 2} nanotubes (positive charge) and the anionic form of Cr(VI) (negative charge), which are prevented recombination (electron–hole pair) by the hole scavenging effect of BPA. In the extended outdoor tests with a rotating type II reactor under solar irradiation, the experiment was extended to examine the simultaneous reduction of Cr(VI) in the presence of additional EDCs, such as EE2 and E2 as well as BPA. The findings showed that synergic effect of both photocatalytic reduction and oxidation was confirmed with single-component (Cr(VI) only), two-components (Cr(VI)/BPA, Cr(VI)/EE2, and Cr(VI)/E2), and four-components (Cr(VI)/BPA/EE2/E2) under various solar irradiation conditions.

  12. HLA class II alleles influence rheumatoid arthritis susceptibility and autoantibody status in South Indian Tamil population.

    Science.gov (United States)

    Mariaselvam, C M; Fortier, C; Charron, D; Krishnamoorthy, R; Tamouza, R; Negi, V S

    2016-11-01

    Rheumatoid arthritis (RA) is a complex multifactorial autoimmune disease characterized by inflammatory arthritis. The precise etiology and pathogenesis of RA remains elusive but evidence points towards stochastic interactions between genetic and environmental factors. This study investigated the distribution of human leucocyte antigen (HLA)-DRB1/DQB1 alleles in South Indian patients with rheumatoid arthritis (RA) and their influence on RA susceptibility and clinical phenotype. Low resolution HLA-DRB1 and -DQB1 typing was performed in 271 RA patients and 233 healthy controls by polymerase chain reaction (PCR) using sequence-specific primers (SSP). HLA-DRB1*10 was found to be more frequent in patients (Pc = 0.004, OR = 2.23, 95% CI = 1.5-3.34) than controls. This difference persisted in RF positive (Pc = 9 × 10(-6) , OR = 2.45, 95% CI = 1.62-3.74), ACPA positive (Pc = 0.007, OR = 2.10, 95% CI = 1.35-3.29), ACPA negative (Pc = 0.001, OR = 2.45, 95% CI = 1.50-3.97) and both RF and ACPA positive subgroup of patients (Pc = 0.003, OR = 2.22, 95% CI = 1.41-3.51). On the contrary, the HLA-DRB1*13 (Pc = 0.01, OR = 0.43, 95% CI = 0.25-0.73) and HLA-DRB1*14 (Pc = 0.003, OR = 0.43, 95% CI = 0.26-0.69) alleles were over-represented in controls than patients. Further, distribution of the prominent Caucasian RA risk allele DRB1*04 did not differ between patients and controls in our study population. We did not find any association between DQB1 alleles and RA susceptibility or autoantibody status. The haplotypes DQB1*05-DRB1*10 (P = 6.8 × 10(-6) , OR = 2.46, 95% CI = 1.63-3.79) and DQB1*06-DRB1*15 (P = 0.03, OR = 1.41, 95% CI = 1.02-1.96) were more frequent in patients while DQB1*05-DRB1*14 (P = 8.4 × 10(-4) , OR = 0.44, 95% CI = 0.26-0.74) and DQB1*06-DRB1*13 (P = 9.5 × 10(-4) , OR = 0.40, 95% CI = 0.21-0.72) were higher in controls. To conclude, HLA-DRB1*10 is associated with RA while HLA-DRB1*13 and HLA-DRB1*14 alleles confer protection in south Indian Tamils. © 2016 John

  13. Photocatalytic reduction of Cr(VI) by small molecular weight organic acids over schwertmannite.

    Science.gov (United States)

    Jiang, Danjun; Li, Ying; Wu, Yong; Zhou, Pei; Lan, Yeqing; Zhou, Lixiang

    2012-10-01

    In this study, a series of bath experiments was carried out to investigate the photoreduction of Cr(VI) by small molecular weight organic acids (SOAs) over schwertmannite, a mineral found in acid mine drainage (AMD). The results demonstrated that schwertmannite or SOAs alone was unable to effectively transform Cr(VI) to Cr(III) even if exposed to an illumination of mimic solar light. However, an addition of schwertmannite significantly enhanced the reduction of Cr(VI) by SOAs under the same condition. For example, 100μM Cr(VI) was almost completely removed within 50min in the presence of both schwertmannite (0.6gL(-1)) and oxalic acid (300μM) at pH 3.0. The photocatalytic reduction of Cr(VI) was strongly influenced by pH, the initial concentrations and the structures of SOAs. Of the tested three SOAs, the reaction rates of photocatalytic reduction of Cr(VI) were in the order of oxalic acid>citric acid>tartaric acid. The reaction obeyed to zero-order kinetics with respect to Cr(VI) with excess SOAs. A possible mechanism for photoreduction of Cr(VI) by SOAs over schwertmannite was proposed. Fe(III) on the surface of schwertmannite was dissolved by SOAs, and then Fe(III)-SOA complexes with high photochemical activity formed. Further, Fe(II) together with organic acid radicals, CO(2)(-) and O(2)(-), was generated through a metal-ligand-charge-transfer pathway (MLCT), leading to a rapid reduction of Cr(VI). Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Survival after major cardiac surgery: performance and comparison of predictive ability of EuroSCORE II and logistic EuroSCORE in a sample of Mediterranean population.

    Science.gov (United States)

    Arnáiz-García, María Elena; González-Santos, Jose María; López-Rodríguez, Javier; Dalmau-Sorlí, María José; Bueno-Codoñer, María; Arévalo-Abascal, Adolfo

    2014-06-01

    The European System for Cardiac Operative Risk Evaluation (EuroSCORE) II has been recently introduced to improve mortality prediction in cardiac surgery. We compare the predictive ability of the new EuroSCORE II with that of the original logistic EuroSCORE and we made an evaluation of a sample of our population submitted to major cardiac surgery in the context of a Mediterranean country. Predicted and observed mortality were recorded in 1,200 consecutive patients undergoing major cardiac surgery at our institution with both logistic EuroSCORE and EuroSCORE II. Patients were grouped according to type of surgery: isolated valvular (n = 538), isolated coronary (n = 322), combined (n = 192), and miscellaneous (n = 148). Predictive capacity of both scales was compared for overall population and for each group in terms of calibration and discrimination using the observed by expected mortality rate, Hosmer-Lemeshow test, and C-statistic. Overall mortality was 6.8%, whereas that predicted by logistic EuroSCORE and EuroSCORE II was 9.7 and 3.7%, respectively. Mortality in our population was higher than mortality expected according to the original EuroSCORE II database. For all groups included in our population, logistic EuroSCORE overestimated mortality and EuroSCORE II underestimated the outcome even more. However, EuroSCORE II showed better calibration than logistic EuroSCORE for overall, valvular, and combined surgery. In contrast, logistic EuroSCORE demonstrated better calibration for coronary surgery. Discrimination capacity was good for both risk scores, but it was superior for logistic EuroSCORE than for EuroSCORE II in all considered subgroups unless combined surgery. Mortality in our population was higher than the mortality that would have been expected by the new EuroSCORE II analysis. Although EuroSCORE II has good calibration and discrimination capacity, both are worse than those demonstrated by logistic EuroSCORE. Forthcoming evaluations are

  15. Constraints on the Geometry of the Obscuring Torus from the NuSTAR Survey of the Local Seyfert II Population

    Science.gov (United States)

    Balokovic, Mislav; Harrison, Fiona; Brightman, Murray

    2017-08-01

    The obscuring torus is one of the main components of the basic unified model of active galactic nuclei (AGN), needed to create anisotropy in obscuration as a function of the viewing angle. We present the first study of the geometrical properties of the AGN torus in a large and representative sample of type II Seyfert nuclei. The sample consists of 124 AGN selected in the hard X-ray band from the Swift/BAT 70-month catalog and observed simultaneously with NuSTAR and Swift/XRT. These data enable us to explore the constraints that observed spectra place on the properties of the obscuring torus in individual AGN and in the local population of Seyfert II nuclei. We make use of empirically motivated spectral models for X-ray reprocessing in approximately toroidal geometry for constraining the distribution of the average column density of the torus, and the distribution of the torus covering factor within this sample. We find that the torus-averaged column density is independent of the line-of-sight column density, with typical column density that is borderline Compton-thick, i.e., around the unity optical depth for Compton scattering. The distribution of torus covering factors is broad but shows a preference for high covering, peaking around the covering factor of 90%, with the median at 70%, in agreement with recent sample studies in the infrared band. We also examine the dependence of the covering factor on intrinsic luminosity, finding that the median covering factor peaks around the intrinsic X-ray luminosity of 10^42.5 erg/s and decreases toward both lower and higher luminosities.

  16. Vi tror ikke noget, vi undersøger det

    DEFF Research Database (Denmark)

    Hansen, Gitte Riis; Winther Johannsen, Inger

    2017-01-01

    I diskussionerne om, hvad der kan betegnes som god viden i forhold til udvikling af pædagogisk ud-vikling og kvalitet, er yderpunkterne kridtet op. Begreber som ”evidensbaseret” og ”datainformeret” synes at udfordre det pædagogiske felts egen forståelse af faglighed og pædagogisk kvalitet. I proj...... tager afsæt i det konkrete projekt og samarbejdet med døgntilbuddene. Vi viser, at arbejdet med datainformeret metode på denne måde ikke er en udradering af pædagogisk faglighed knyttet til fagprofessionel dømmekraft – snarere tværtimod...

  17. Flow-through Column Experiments and Modeling of Microbially Mediated Cr(VI) Reduction at Hanford 100H

    Science.gov (United States)

    Yang, L.; Molins, S.; Beller, H. R.; Brodie, E. L.; Steefel, C.; Nico, P. S.; Han, R.

    2010-12-01

    transport simulations suggested that direct reduction of Cr(VI) by Fe(II) and Mn(II) released from the sediment could account for the observed Cr(VI) removal. The biogeochemical modeling was employed to test two hypotheses that could explain the release of Fe(II) and Mn(II) from the column sediments: 1) acetate produced by lactate fermentation provided the substrate for the growth of iron(III) and manganese(IV) oxide reducers, and 2) direct reduction of iron(III) and manganese(IV) oxides by hydrogen sulfide generated during sulfate reduction. Overall, experimental and modeling results suggested that Cr(VI) reduction in the sulfate-reducing columns occurred through a complex network of microbial reactions that included fermentation, sulfate reduction, and possibly the stimulated iron-reducing communities.

  18. Infection with Trypanosoma cruzi TcII and TcI in free-ranging population of lion tamarins (Leontopithecus spp: an 11-year follow-up

    Directory of Open Access Journals (Sweden)

    Cristiane Varella Lisboa

    2015-05-01

    Full Text Available Here, we present a review of the dataset resulting from the 11-years follow-up of Trypanosoma cruzi infection in free-ranging populations of Leontopithecus rosalia (golden lion tamarin and Leontopithecus chrysomelas (golden-headed lion tamarin from distinct forest fragments in Atlantic Coastal Rainforest. Additionally, we present new data regarding T. cruzi infection of small mammals (rodents and marsupials that live in the same areas as golden lion tamarins and characterisation at discrete typing unit (DTU level of 77 of these isolates. DTU TcII was found to exclusively infect primates, while TcI infected Didelphis aurita and lion tamarins. The majority of T. cruzi isolates derived from L. rosalia were shown to be TcII (33 out 42 Nine T. cruzi isolates displayed a TcI profile. Golden-headed lion tamarins demonstrated to be excellent reservoirs of TcII, as 24 of 26 T. cruzi isolates exhibited the TcII profile. We concluded the following: (i the transmission cycle of T. cruzi in a same host species and forest fragment is modified over time, (ii the infectivity competence of the golden lion tamarin population fluctuates in waves that peak every other year and (iii both golden and golden-headed lion tamarins are able to maintain long-lasting infections by TcII and TcI.

  19. Mens vi venter på finansloven ..

    DEFF Research Database (Denmark)

    Madsen, Mogens Ove

    2011-01-01

    Vi må dog lufte en forsigtig optimisme over, at der kom signaler om opgør med detailstyring og knopskydningen af øremærket forskning.......Vi må dog lufte en forsigtig optimisme over, at der kom signaler om opgør med detailstyring og knopskydningen af øremærket forskning....

  20. Når vi taler om 68

    DEFF Research Database (Denmark)

    Jensen, Henrik; Metz, Georg

    Når vi taler om 68 er en intellektuel samtale mellem to ligeværdige gentlemen og skallesmækkere. En essayistisk dyst om porno, RAF, Pittelkow og livsfilosofi......Når vi taler om 68 er en intellektuel samtale mellem to ligeværdige gentlemen og skallesmækkere. En essayistisk dyst om porno, RAF, Pittelkow og livsfilosofi...

  1. MURALS WITH A ViBe

    National Research Council Canada - National Science Library

    Drake, Leigh

    2017-01-01

    The ViBe District in Virginia Beach is a hub for the local arts community. There is a fenced area in the ViBe District that features a whole row of murals created by professional artists, amateurs, and student groups from all over...

  2. Redefining high-risk patients with stage II colon cancer by risk index and microRNA-21: results from a population-based cohort

    DEFF Research Database (Denmark)

    Hansen, T F; Kjær-Frifeldt, S; Christensen, R D

    2014-01-01

    Background:The aim of the present study was to analyse the prognostic value of microRNA-21 (miRNA-21) in patients with stage II colon cancer aiming at a risk index for this group of patients.Methods:A population-based cohort of 554 patients was included. MicroRNA-21 was analysed by qPCR based on ...

  3. Redefining high-risk patients with stage II colon cancer by risk index and microRNA-21: results from a population-based cohort

    DEFF Research Database (Denmark)

    Hansen, T F; Kjær-Frifeldt, S; Christensen, R D

    2014-01-01

    Background:The aim of the present study was to analyse the prognostic value of microRNA-21 (miRNA-21) in patients with stage II colon cancer aiming at a risk index for this group of patients.Methods:A population-based cohort of 554 patients was included. MicroRNA-21 was analysed by qPCR based...

  4. Econophys-Kolkata VI Conference

    CERN Document Server

    Chakrabarti, Bikas; Chakraborti, Anirban; Ghosh, Asim

    2013-01-01

    The primary goal of the book is to present the ideas and research findings of active researchers such as physicists, economists, mathematicians and financial engineers working in the field of “Econophysics,” who have undertaken the task of modeling and analyzing systemic risk, network dynamics and other topics. Of primary interest in these studies is the aspect of systemic risk, which has long been identified as a potential scenario in which financial institutions trigger a dangerous contagion mechanism, spreading from the financial economy to the real economy. This type of risk, long confined to the monetary market, has spread considerably in the recent past, culminating in the subprime crisis of 2008. As such, understanding and controlling systemic risk has become an extremely important societal and economic challenge. The Econophys-Kolkata VI conference proceedings are dedicated to addressing a number of key issues involved. Several leading researchers in these fields report on their recent work and al...

  5. Negative selection and peptide chemistry determine the size of naive foreign peptide-MHC class II-specific CD4+ T cell populations.

    Science.gov (United States)

    Chu, H Hamlet; Moon, James J; Kruse, Andrew C; Pepper, Marion; Jenkins, Marc K

    2010-10-15

    Naive CD4(+) T cell populations that express TCRs specific for different foreign peptide-MHC class II complex (pMHCII) ligands can vary in size over several orders of magnitude. This variation may explain why immune responses to some peptides are stronger than others. In this study, we used a sensitive pMHCII-tetramer-based cell enrichment method to study the derivation of two naive foreign pMHCII-specific naive CD4(+) T cell populations that differed in size by 8-fold in normal mice. Analysis of mice in which thymic negative selection was impaired revealed that the smaller population underwent more clonal deletion than the larger population. In addition, large naive cell populations tended to recognize peptides with tryptophan residues as TCR contacts. Thus, the foreign pMHCII that tend to be recognized by large naive populations induce minimal clonal deletion and contain certain amino acids with the capacity to interact favorably with TCRs.

  6. Dissimilatory Reduction of Cr(VI), Fe(III), and U(VI) by Cellulomonas Isolates

    Energy Technology Data Exchange (ETDEWEB)

    Smith, William Aaron; Apel, William Arnold; Peyton, B. M.; Petersen, J. N.; Sani, R.

    2002-10-01

    The reduction of Cr(VI), Fe(III), and U(VI) was studied using three recently isolated environmental Cellulomonas sp. (WS01, WS18, and ES5) and a known Cellulomonas strain (Cellulomonas flavigena ATCC 482) under anaerobic, non-growth conditions. In all cases, these cultures were observed to reduce Cr(VI), Fe(III), and U(VI). In 100 h, with lactate as electron donor, the Cellulomonas isolates (500 mg/l total cell protein) reduced nitrilotriacetic acid chelated Fe(III) [Fe(III)-NTA] from 5 mM to less than 2.2 mM, Cr(VI) from 0.2 mM to less than 0.001 mM, and U(VI) from 0.2 mM to less than 0.12 mM. All Cellulomonas isolates also reduced Cr(VI), Fe(III), and U(VI) in the absence of lactate, while no metal reduction was observed in either the cell-free or heat-killed cell controls. This is the first report of Cellulomonas sp. reducing Fe(III) and U(VI). Further, this is the first report of Cellulomonas spp. coupling the oxidation of lactate, or other unknown electron donors in the absence of lactate, to the reduction of Cr(VI), Fe(III), and U(VI).

  7. Dissimilatory reduction of Cr(VI), Fe(III), and U(VI) by Cellulomonas isolates.

    Science.gov (United States)

    Sani, R K; Peyton, B M; Smith, W A; Apel, W A; Petersen, J N

    2002-10-01

    The reduction of Cr(VI), Fe(III), and U(VI) was studied using three recently isolated environmental Cellulomonas sp. (WS01, WS18, and ES5) and a known Cellulomonas strain ( Cellulomonas flavigena ATCC 482) under anaerobic, non-growth conditions. In all cases, these cultures were observed to reduce Cr(VI), Fe(III), and U(VI). In 100 h, with lactate as electron donor, the Cellulomonas isolates (500 mg/l total cell protein) reduced nitrilotriacetic acid chelated Fe(III) [Fe(III)-NTA] from 5 mM to less than 2.2 mM, Cr(VI) from 0.2 mM to less than 0.001 mM, and U(VI) from 0.2 mM to less than 0.12 mM. All Cellulomonas isolates also reduced Cr(VI), Fe(III), and U(VI) in the absence of lactate, while no metal reduction was observed in either the cell-free or heat-killed cell controls. This is the first report of Cellulomonas sp. reducing Fe(III) and U(VI). Further, this is the first report of Cellulomonas spp. coupling the oxidation of lactate, or other unknown electron donors in the absence of lactate, to the reduction of Cr(VI), Fe(III), and U(VI).

  8. Genetics Home Reference: collagen VI-related myopathy

    Science.gov (United States)

    ... Twitter Home Health Conditions Collagen VI-related myopathy Collagen VI-related myopathy Printable PDF Open All Close ... Javascript to view the expand/collapse boxes. Description Collagen VI-related myopathy is a group of disorders ...

  9. Finite difference simulation of biological chromium (VI) reduction in ...

    African Journals Online (AJOL)

    (VI) concentration profiles inside porous aquifer media columns. The model was thereafter used to calculate Cr(VI) removal rate for a range of Cr(VI) loadings. Internal concentration profiles were modelled against data collected from ...

  10. Are dietary habits of the Polish population consistent with the recommendations for prevention of cardiovascular disease? - WOBASZ II project.

    Science.gov (United States)

    Waśkiewicz, Anna; Szcześniewska, Danuta; Szostak-Węgierek, Dorota; Kwaśniewska, Magdalena; Pająk, Andrzej; Stepaniak, Urszula; Kozakiewicz, Krystyna; Tykarski, Andrzej; Zdrojewski, Tomasz; Zujko, Małgorzata E; Drygas, Wojciech

    2016-01-01

    Diet is a modifiable risk factor for cardiovascular disease (CVD). To assess diet quality in the adult Polish population, taking into consideration consumption of various nutrients as well as the total diet quality. Within the frame of the National Multicentre Health Survey (WOBASZ II), a random sample of the whole Polish population aged 20 years and above was screened during the years 2013-2014. Dietary habits were assessed in 5690 subjects (2554 men and 3136 women). Nutrient intakes were compared to the Dietary Reference Intakes. Total diet quality was measured using the Healthy Diet Indicator (HDI) score, based on the World Health Organisation recommendations for CVD prevention, that includes 7 nutrients (saturated and polyunsaturated fatty acids, cholesterol, protein, dietary fibre, fruits and vegetables, free sugars) and ranges from 0 (the least healthy diet) to 7 (the healthiest diet). The studied group was characterised by a high prevalence of overweight and obesity (69% in men vs. 59% in women), hypercholesterolaemia (56% vs. 55%, respectively), hypertension (50% vs. 42%), and diabetes (12% vs. 10%). At the same time, a significant percentage of Poles had improper dietary habits. A low fat and low cholesterol diet was reported by only 8% and a low calorie diet by 1% of the respondents. Adding salt to already seasoned dishes was reported by 27% of men and 18% of women, and 56% and 30% of them, respectively, consumed meat products with visible fat. The diet of most adult Polish citizens was found to be not balanced. Vitamins A, C, E, B1, B2, B6, and B12, protein, dietary cholesterol and fruits/vegetables were consumed in recommended doses only by 44-80% of the respondents. The recommended intake of fat, saturated and polyunsaturated fatty acids, which significantly affect lipid levels, was found in 18-37% of the respondents. Dietary intakes of folate and minerals important for the prevention of hypertension were insufficient. The desired level of folate

  11. HMGA2 plays an important role in Cr (VI)-induced autophagy.

    Science.gov (United States)

    Yang, Fan; Zhao, Lian; Mei, Dan; Jiang, Liping; Geng, Chengyan; Li, Qiujuan; Yao, Xiaofeng; Liu, Yong; Kong, Ying; Cao, Jun

    2017-09-01

    Cr (VI) is mutagenic and carcinogenic, but the mechanism is unclear. In this study, the involvement of high mobility group A2 (HMGA2) in Cr (VI)-induced autophagy was investigated. Cr (VI) treatment induced formation of autophagosomes, increased expression of LC3II, Atg12-Atg5, Atg4, Atg10, HMGA1 and HMGA2 proteins, and decreased the expression of p62 in A549 cells. Silencing of HMGA2 gene by siRNA blocked Cr (VI)-induced formation of autophagosomes, expression of LC3II, Atg12-Atg5, Atg10 and reduction of p62. Overexpression of HMGA2 in HEK 293 and HeLa cells could induce the expression of LC3II, Atg12-Atg5 and Atg10, and decrease the expression of p62. Although the protein level of Atg12-Atg5 conjugation changed after Cr (VI) treatment, silencing of HMGA2 and overexpression of HMGA2, both the proteins and mRNA levels of Atg12 and Atg5 were not changed significantly. ChIP assay demonstrated that HMGA2 protein directly bound to the promoter sequence of Atg10 gene, which modulated the conjugation of Atg12-Atg5. Interestingly, 3-MA markedly prevented Cr (VI)-induced cell growth of A549 cells. Our further in vivo study confirmed that the expression of HMGA1, HMGA2, LC3II, Atg12-Atg5, Atg4, Atg5, Atg7, Atg10, Atg12, Beclin 1 were increased and p62 was reduced in lung tissues of Cr (VI)-treated BALB/c mice. Combining, our data demonstrated that HMGA2 plays an important role in Cr (VI)-induced autophagy and the mechanism underlies Atg12-Atg5 conjugation modulated by HMGA2-dependent transcriptional regulation of Atg10. This suggests that HMGA2 might be an important biomarker in Cr (VI)-induced autophagy, cell-growth or other toxicities. © 2017 UICC.

  12. Mucopolysaccharidosis VI in cats - clarification regarding genetic testing.

    Science.gov (United States)

    Lyons, Leslie A; Grahn, Robert A; Genova, Francesca; Beccaglia, Michela; Hopwood, John J; Longeri, Maria

    2016-07-02

    The release of new DNA-based diagnostic tools has increased tremendously in companion animals. Over 70 different DNA variants are now known for the cat, including DNA variants in disease-associated genes and genes causing aesthetically interesting traits. The impact genetic tests have on animal breeding and health management is significant because of the ability to control the breeding of domestic cats, especially breed cats. If used properly, genetic testing can prevent the production of diseased animals, causing the reduction of the frequency of the causal variant in the population, and, potentially, the eventual eradication of the disease. However, testing of some identified DNA variants may be unwarranted and cause undo strife within the cat breeding community and unnecessary reduction of gene pools and availability of breeding animals. Testing for mucopolysaccharidosis Type VI (MPS VI) in cats, specifically the genetic testing of the L476P (c.1427T>C) and the D520N (c.1558G>A) variants in arylsulfatase B (ARSB), has come under scrutiny. No health problems are associated with the D520N (c.1558G>A) variant, however, breeders that obtain positive results for this variant are speculating as to possible correlation with health concerns. Birman cats already have a markedly reduced gene pool and have a high frequency of the MPS VI D520N variant. Further reduction of the gene pool by eliminating cats that are heterozygous or homozygous for only the MPS VI D520N variant could lead to more inbreeding depression effects on the breed population. Herein is debated the genetic testing of the MPS VI D520N variant in cats. Surveys from different laboratories suggest the L476P (c.1427T>C) disease-associated variant should be monitored in the cat breed populations, particularly breeds with Siamese derivations and outcrosses. However, the D520N has no evidence of association with disease in cats and testing is not recommended in the absence of L476P genotyping. Selection

  13. Stellar Populations and Structural Properties of Ultra Faint Dwarf Galaxies, Canes Venatici I, Boötes I, Canes Venatici II, and Leo IV

    Science.gov (United States)

    Okamoto, Sakurako; Arimoto, Nobuo; Yamada, Yoshihiko; Onodera, Masato

    2012-01-01

    We take deep images of four ultra faint dwarf (UFD) galaxies, Canes Venatici I (CVn I), Boötes I (Boö I), Canes Venatici II (CVn II), and Leo IV, using the Suprime-Cam on the Subaru Telescope. Color-magnitude diagrams (CMDs) extend below main-sequence turnoffs (MSTOs) and yield measurements of the ages of stellar populations. The stellar populations of three faint galaxies, the Boö I, CVn II, and Leo IV dwarf spheroidal galaxies (dSphs), are estimated to be as old as the Galactic globular cluster M92. We confirm that Boö I dSph has no intrinsic color spread in the MSTO and no spatial difference in the CMD morphology, which indicates that Boö I dSph is composed of an old single stellar population. One of the brightest UFDs, CVn I dSph, shows a relatively younger age (~12.6 Gyr) with respect to Boö I, CVn II, and Leo IV dSphs, and the distribution of red horizontal branch (HB) stars is more concentrated toward the center than that of blue HB stars, suggesting that the galaxy contains complex stellar populations. Boö I and CVn I dSphs show the elongated and distorted shapes. CVn II dSph has the smallest tidal radius of a Milky Way satellite and has a distorted shape, while Leo IV dSph shows a less concentrated spherical shape. The simple stellar population of faint UFDs indicates that the gases in their progenitors were removed more effectively than those of brighter dSphs at the occurrence of their initial star formation. This is reasonable if the progenitors of UFDs belong to less massive halos than those of brighter dSphs. Based on data collected at the Subaru Telescope, which is operated by the National Astronomical Observatory of Japan.

  14. Glutamatergic Nonpyramidal Neurons From Neocortical Layer VI and Their Comparison With Pyramidal and Spiny Stellate Neurons

    Science.gov (United States)

    Andjelic, Sofija; Gallopin, Thierry; Cauli, Bruno; Hill, Elisa L.; Roux, Lisa; Badr, Sammy; Hu, Emilie; Tamás, Gábor; Lambolez, Bertrand

    2009-01-01

    The deeper part of neocortical layer VI is dominated by nonpyramidal neurons, which lack a prominent vertically ascending dendrite and predominantly establish corticocortical connections. These neurons were studied in rat neocortical slices using patch-clamp, single-cell reverse transcription–polymerase chain reaction, and biocytin labeling. The majority of these neurons expressed the vesicular glutamate transporter but not glutamic acid decarboxylase, suggesting that a high proportion of layer VI nonpyramidal neurons are glutamatergic. Indeed, they exhibited numerous dendritic spines and established asymmetrical synapses. Our sample of glutamatergic nonpyramidal neurons displayed a wide variety of somatodendritic morphologies and a subset of these cells expressed the Nurr1 mRNA, a marker for ipsilateral, but not commissural corticocortical projection neurons in layer VI. Comparison with spiny stellate and pyramidal neurons from other layers showed that glutamatergic neurons consistently exhibited a low occurrence of GABAergic interneuron markers and regular spiking firing patterns. Analysis of electrophysiological diversity using unsupervised clustering disclosed three groups of cells. Layer V pyramidal neurons were segregated into a first group, whereas a second group consisted of a subpopulation of layer VI neurons exhibiting tonic firing. A third heterogeneous cluster comprised spiny stellate, layer II/III pyramidal, and layer VI neurons exhibiting adaptive firing. The segregation of layer VI neurons in two different clusters did not correlate either with their somatodendritic morphologies or with Nurr1 expression. Our results suggest that electrophysiological similarities between neocortical glutamatergic neurons extend beyond layer positioning, somatodendritic morphology, and projection specificity. PMID:19052106

  15. String cosmology in Bianchi type-VI0 dusty Universe with ...

    Indian Academy of Sciences (India)

    In this paper, the effect of electromagnetic field in the string Bianchi type-VI0 Universe is investigated. Einstein's field equations have been solved exactly with suitable physical assumptions for two types of strings: (i) massive strings and (ii) Nambu strings. It is found that when the Universe is dominated by massive strings, ...

  16. Cr(Vi) reduction capacity of activated sludge as affected by nitrogen and carbon sources, microbial acclimation and cell multiplication

    Energy Technology Data Exchange (ETDEWEB)

    Ferro Orozco, A.M., E-mail: mferro@cidca.org.ar [Centro de Investigacion y Desarrollo en Criotecnologia de Alimentos (CIDCA) CCT La Plata CONICET - Fac. de Cs. Exactas, UNLP. 47 y 116 (B1900AJJ) La Plata (Argentina); Contreras, E.M.; Zaritzky, N.E. [Centro de Investigacion y Desarrollo en Criotecnologia de Alimentos (CIDCA) CCT La Plata CONICET - Fac. de Cs. Exactas, UNLP. 47 y 116 (B1900AJJ) La Plata (Argentina); Fac. de Ingenieria, UNLP. 47 y 1 (B1900AJJ) - La Plata (Argentina)

    2010-04-15

    The objectives of the present work were: (i) to analyze the capacity of activated sludge to reduce hexavalent chromium using different carbon sources as electron donors in batch reactors, (ii) to determine the relationship between biomass growth and the amount of Cr(VI) reduced considering the effect of the nitrogen to carbon source ratio, and (iii) to determine the effect of the Cr(VI) acclimation stage on the performance of the biological chromium reduction assessing the stability of the Cr(VI) reduction capacity of the activated sludge. The highest specific Cr(VI) removal rate (q{sub Cr}) was attained with cheese whey or lactose as electron donors decreasing in the following order: cheese whey {approx} lactose > glucose > citrate > acetate. Batch assays with different nitrogen to carbon source ratio demonstrated that biological Cr(VI) reduction is associated to the cell multiplication phase; as a result, maximum Cr(VI) removal rates occur when there is no substrate limitation. The biomass can be acclimated to the presence of Cr(VI) and generate new cells that maintain the ability to reduce chromate. Therefore, the activated sludge process could be applied to a continuous Cr(VI) removal process.

  17. Emissions of chromium (VI) from arc welding.

    Science.gov (United States)

    Heung, William; Yun, Myoung-Jin; Chang, Daniel P Y; Green, Peter G; Halm, Chris

    2007-02-01

    The presence of Cr in the +6 oxidation state (Cr[VI]) is still observed in ambient air samples in California despite steps taken to reduce emissions from plating operations. One known source of emission of Cr(VI) is welding, especially with high Cr-content materials, such as stainless steels. An experimental effort was undertaken to expand and update Cr(VI) emission factors by conducting tests on four types of arc-welding operations: gas-metal arc welding (GMAW), shielded metal arc welding (SMAW), fluxcore arc welding, and pulsed GMAW. Standard American Welding Society hood results were compared with a total enclosure method that permitted isokinetic sampling for particle size-cut measurement, as well as total collection of the aerosol. The fraction of Cr(VI) emitted per unit mass of Cr electrode consumed was determined. Consistent with AP-42 data, initial results indicate that a significant fraction of the total Cr in the aerosol is in the +6 oxidation state. The fraction of Cr(VI) and total aerosol mass produced by the different arc welding methods varies with the type of welding process used. Self-shielded electrodes that do not use a shield gas, for example, SMAW, produce greater amounts of Cr(VI) per unit mass of electrode consumed. The formation of Cr(VI) from standard electrode wires used for welding mild steel was below the method detection limit after eliminating an artifact in the analytical method used.

  18. Anaerobic bio-removal of uranium (VI) and chromium (VI): Comparison of microbial community structure

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Monica [Centro de Ciencias do Mar, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Faleiro, Maria Leonor [IBB - Centro de Biomedicina Molecular e Estrutural, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Chaves, Sandra; Tenreiro, Rogerio [Universidade de Lisboa, Faculdade de Ciencias, Centro de Biodiversidade, Genomica Integrativa e Funcional (BioFIG), Campus de FCUL, Campo Grande 1749-016 Lisboa (Portugal); Santos, Erika [Centro de Ciencias do Mar, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Costa, Maria Clara, E-mail: mcorada@ualg.pt [Centro de Ciencias do Mar, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal)

    2010-04-15

    Several microbial communities, obtained from uranium contaminated and non-contaminated samples, were investigated for their ability to remove uranium (VI) and the cultures capable for this removal were further assessed on their efficiency for chromium (VI) removal. The highest efficiency for removal of both metals was observed on a consortium from a non-contaminated soil collected in Monchique thermal place, which was capable to remove 91% of 22 mg L{sup -1} U(VI) and 99% of 13 mg L{sup -1} Cr(VI). This study revealed that uranium (VI) removing communities have also ability to remove chromium (VI), but when uranium (VI) was replaced by chromium (VI) several differences in the structure of all bacterial communities were observed. TGGE and phylogenetic analysis of 16S rRNA gene showed that the uranium (VI) removing bacterial consortia are mainly composed by members of Rhodocyclaceae family and Clostridium genus. On the other hand, bacteria from Enterobacteriaceae family were detected in the community with ability for chromium (VI) removal. The existence of members of Enterobacteriaceae and Rhodocyclaceae families never reported as chromium or uranium removing bacteria, respectively, is also a relevant finding, encouraging the exploitation of microorganisms with new abilities that can be useful for bioremediation.

  19. Validating the Beck Depression Inventory-II in Indonesia’s general population and coronary heart disease patients

    Directory of Open Access Journals (Sweden)

    Henndy Ginting

    2013-01-01

    Full Text Available Este estudio evalúa la validez y determina los puntos de corte del Inventario de Depresión de Beck -II (BDI-II en Indonesia. La versión indonesia del BDI-II (BDI-II Indo se administró a 720 personas sanas de la población general, a 215 pacientes con Enfermedad Coronaria (EC y a 102 pacientes con depresión. El análisis factorial confirmatorio mostró similitud factorial de las tres muestras. Las correlaciones entre el Indo BDI-II y otras medidas de auto-percepción relacionadas con la depresión fueron significativas, mostrando la validez de constructo del Indo BDI-II. Además, la diferencia de puntuación del Indo BDI-II entre los participantes deprimidos y no deprimidos fue altamente significativa. La consistencia interna y la fiabilidad re- test fueron suficientemente altas. La curva ROC (receiver operating characteristic indicó que el punto de corte de la BDI-II para el nivel de gravedad leve de depresión la población de Indonesia es igual a 17. En conclusión, el Indo BDI-II es una medida válida de depresión, tanto para la población general indonesia como en pacientes con EC.

  20. Prevention of non-communicable disease in a population in nutrition transition: Tehran Lipid and Glucose Study phase II

    Directory of Open Access Journals (Sweden)

    Hedayati Mehdi

    2009-01-01

    Full Text Available Abstract Background The Tehran Lipid and Glucose Study (TLGS is a long term integrated community-based program for prevention of non-communicable disorders (NCD by development of a healthy lifestyle and reduction of NCD risk factors. The study begun in 1999, is ongoing, to be continued for at least 20 years. A primary survey was done to collect baseline data in 15005 individuals, over 3 years of age, selected from cohorts of three medical heath centers. A questionnaire for past medical history and data was completed during interviews; blood pressure, pulse rate, and anthropometrical measurements and a limited physical examination were performed and lipid profiles, fasting blood sugar and 2-hours-postload-glucose challenge were measured. A DNA bank was also collected. For those subjects aged over 30 years, Rose questionnaire was completed and an electrocardiogram was taken. Data collected were directly stored in computers as database software- computer assisted system. The aim of this study is to evaluate the feasibility and effectiveness of lifestyle modification in preventing or postponing the development of NCD risk factors and outcomes in the TLGS population. Design and methods In phase II of the TLGS, lifestyle interventions were implemented in 5630 people and 9375 individuals served as controls. Primary, secondary and tertiary interventions were designed based on specific target groups including schoolchildren, housewives, and high-risk persons. Officials of various sectors such as health, education, municipality, police, media, traders and community leaders were actively engaged as decision makers and collaborators. Interventional strategies were based on lifestyle modifications in diet, smoking and physical activity through face-to-face education, leaflets & brochures, school program alterations, training volunteers as health team and treating patients with NCD risk factors. Collection of demographic, clinical and laboratory data will be

  1. Learning the vi and Vim Editor

    CERN Document Server

    Robbins, Arnold; Hannah, Elbert

    2008-01-01

    There's nothing that hard-core Unix and Linux users are more fanatical about than their text editor. Editors are the subject of adoration and worship, or of scorn and ridicule, depending upon whether the topic of discussion is your editor or someone else's. vi has been the standard editor for close to 30 years. Popular on Unix and Linux, it has a growing following on Windows systems, too. Most experienced system administrators cite vi as their tool of choice. And since 1986, this book has been the guide for vi. However, Unix systems are not what they were 30 years ago, and neither is this

  2. Mucopolissacaridose tipo VI: relato de caso

    OpenAIRE

    Lais Orosco Bialon Santana; Carolina Ando Matsuno; Marta Wey Vieira

    2014-01-01

    Introdução: As mucopolissacaridoses são erros inatos do metabolismo de depósito lisossomal subclassificadas segundo a enzima deficiente. A arilsulfatase B (ARSB), responsável por degradar os glicosaminoglicanos (GAGs), que atuam no tecido conjuntivo, é deficiente na mucopolissacaridose tipo VI (MP VI). A MP VI tem clínica variável, sem anormalidades ao nascimento, evidenciando-se progressivamente ao acúmulo de GAGs. O diagnóstico se faz pela redução da atividade da ARSB ou da mutação genética...

  3. Low genetic variation in the MHC class II DRB gene and MHC-linked microsatellites in endangered island populations of the leopard cat (Prionailurus bengalensis) in Japan.

    Science.gov (United States)

    Saka, Toshinori; Nishita, Yoshinori; Masuda, Ryuichi

    2017-07-09

    Isolated populations of the leopard cat (Prionailurus bengalensis) on Tsushima and Iriomote islands in Japan are classified as subspecies P. b. euptilurus and P. b. iriomotensis, respectively. Because both populations have decreased to roughly 100, an understanding of their genetic diversity is essential for conservation. We genotyped MHC class II DRB exon 2 and MHC-linked microsatellite loci to evaluate the diversity of MHC genes in the Tsushima and Iriomote cat populations. We detected ten and four DRB alleles in these populations, respectively. A phylogenetic analysis showed DRB alleles from both populations to be closely related to those in other felid DRB lineages, indicating trans-species polymorphism. The MHC-linked microsatellites were more polymorphic in the Tsushima than in the Iriomote population. The MHC diversity of both leopard cat populations is much lower than in the domestic cat populations on these islands, probably due to inbreeding associated with founder effects, geographical isolation, or genetic drift. Our results predict low resistance of the two endangered populations to new pathogens introduced to the islands.

  4. ViSIT: Visitor Survey Information Tool

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — ViSIT is an interactive web tool created by USGS to visualize the data collected as part of the National Wildlife Refuge Visitor Survey. The national survey was...

  5. Cr(VI) removal from aqueous systems using pyrite as the reducing agent: batch, spectroscopic and column experiments.

    Science.gov (United States)

    Kantar, Cetin; Ari, Cihan; Keskin, Selda; Dogaroglu, Zeynep Gorkem; Karadeniz, Aykut; Alten, Akin

    2015-03-01

    Laboratory batch and column experiments, in conjunction with geochemical calculations and spectroscopic analysis, were performed to better understand reaction mechanisms and kinetics associated with Cr(VI) removal from aqueous systems using pyrite as the reactive material under both static and dynamic flow conditions similar to those observed in in situ permeable reactive barriers (PRBs). The X-ray photoelectron spectroscopy (XPS) and geochemical calculations suggest that the Cr(VI) removal by pyrite occurred due to the reduction of Cr(VI) to Cr(III), coupled with the oxidation of Fe(II) to Fe(III) and S2(2-) to SO4(2-) at the pyrite surface. Zeta potential measurements indicate that although the pyrite surface was negatively charged under a wide pH range in the absence of Cr(VI), it behaved more like a "metal oxide" surface with the surface potential shifting from positive to negative values at pH values >pH 6 in the presence of Cr(VI). Batch experiments show that increasing solution pH led to a significant decrease in Cr(VI) removal. The decrease in Cr(VI) removal at high Cr(VI) concentrations and pH values can be explained through the precipitation of sparingly soluble Cr(OH)(3(s)), Fe(OH)(3(s)) and Fe(III)-Cr(III) (oxy) hydroxides onto pyrite surface which may, then, lead to surface passivation for further Cr(VI) reduction. Batch results also suggest that the reaction kinetics follow a first order model with rate constants decreasing with increasing solution pH, indicating proton consumption during Cr(VI) reduction by pyrite. Column experiments indicate that nearly 100% of total Fe in the column effluent was in the form of Fe(II) species with a [SO4(2-)]/[Fe(2+)] stoichiometric ratio of 2.04, indicating that the reduction of Cr(VI) by pyrite produced about 2 mol of sulfate per mole of Fe (II) release under excess surface sites relative to Cr(VI) concentration. Column experiments provide further evidence on the accumulation of oxidation products which

  6. Cr(VI) removal from aqueous systems using pyrite as the reducing agent: Batch, spectroscopic and column experiments

    Science.gov (United States)

    Kantar, Cetin; Ari, Cihan; Keskin, Selda; Dogaroglu, Zeynep Gorkem; Karadeniz, Aykut; Alten, Akin

    2015-03-01

    Laboratory batch and column experiments, in conjunction with geochemical calculations and spectroscopic analysis, were performed to better understand reaction mechanisms and kinetics associated with Cr(VI) removal from aqueous systems using pyrite as the reactive material under both static and dynamic flow conditions similar to those observed in in situ permeable reactive barriers (PRBs). The X-ray photoelectron spectroscopy (XPS) and geochemical calculations suggest that the Cr(VI) removal by pyrite occurred due to the reduction of Cr(VI) to Cr(III), coupled with the oxidation of Fe(II) to Fe(III) and S22 - to SO42 - at the pyrite surface. Zeta potential measurements indicate that although the pyrite surface was negatively charged under a wide pH range in the absence of Cr(VI), it behaved more like a "metal oxide" surface with the surface potential shifting from positive to negative values at pH values > pH 6 in the presence of Cr(VI). Batch experiments show that increasing solution pH led to a significant decrease in Cr(VI) removal. The decrease in Cr(VI) removal at high Cr(VI) concentrations and pH values can be explained through the precipitation of sparingly soluble Cr(OH)3(s), Fe(OH)3(s) and Fe(III)-Cr(III) (oxy) hydroxides onto pyrite surface which may, then, lead to surface passivation for further Cr(VI) reduction. Batch results also suggest that the reaction kinetics follow a first order model with rate constants decreasing with increasing solution pH, indicating proton consumption during Cr(VI) reduction by pyrite. Column experiments indicate that nearly 100% of total Fe in the column effluent was in the form of Fe(II) species with a [SO42 -]/[Fe2 +] stoichiometric ratio of 2.04, indicating that the reduction of Cr(VI) by pyrite produced about 2 mol of sulfate per mole of Fe (II) release under excess surface sites relative to Cr(VI) concentration. Column experiments provide further evidence on the accumulation of oxidation products which consequently led

  7. Epitaxial overgrowth of II-VI compounds on patterned substrates

    Energy Technology Data Exchange (ETDEWEB)

    Schikora, D. (Inst. fuer Halbleiterphysik und Optik, Technische Univ. Braunschweig, Braunschweig (Germany)); Hausleitner, H. (Forschungsinst. fuer Optoelektronik, Univ. Linz (Austria)); Einfeldt, S. (and others)

    1994-04-14

    The selected area epitaxial overgrowth of narrow gap HgTe as well as wide gap CdTe and ZnTe on CdTe/GaAs substrates, which had been structured by dry etching techniques, has been investigated. A plasma etching process using a barrel reactor with CH[sub 4]-H[sub 2] gases has been employed to prepare stripes with a width of about 1 [mu]m with anisotropic as well as isotropic etching profiles. It has been found, that the selected area HgTe overgrowth takes place with a high local selectivity to the low index planes of the patterned surface. In contrast, the selected area overgrowth of the wide gap CdTe and ZnTe is controlled by anisotropic growth kinetics provided that the substrate temperature is not lower than 220[sup o]C and the starting surface consists of well developed low index crystallographic planes

  8. Photophysical Properties of II-VI Semiconductor Nanocrystals

    OpenAIRE

    Gong, Ke

    2015-01-01

    As it is well known, semiconductor nanocrystals (also called quantum dots, QDs) are being actively pursued for use in many different types of luminescent optical materials. These materials include the active media for luminescence downconversion in artificial lighting, lasers, luminescent solar concentrators and many other applications. Chapter 1 gives general introduction of QDs, which describe the basic physical properties and optical properties. Based on the experimental spectroscopic stu...

  9. Social Set Visualizer (SoSeVi) II

    DEFF Research Database (Denmark)

    Flesch, Benjamin; Vatrapu, Ravi; Mukkamala, Raghava Rao

    2016-01-01

    Current state-of-the-art in big social data analytics is largely limited to graph theoretical approaches such as social network analysis (SNA) informed by the social philosophical approach of relational sociology. This paper proposes and illustrates an alternate holistic approach to big social data...... analytics, social set analysis (SSA), which is based on the sociology of associations, mathematics of set theory, and advanced visual analytics of event studies. We first presented the SSA approach to a wider audience at IEEE Big Data 2015 [6], IEEE EDOCW 2015 [7], and IEEE EDOCW 2016 [8]. Since then we...... [14] and aims to further improve the capabilities of researchers and practitioners in big social data analytics alike. We then illustrate our new approach by reporting on the design, development, and evaluation results of a state-of-theart visual analytics dashboard, the Social Set Visualizer (So...

  10. Quaternary alloys based on II-VI semiconductors

    CERN Document Server

    Tomashyk, Vasyl

    2014-01-01

    Systems Based on ZnSSystems Based on ZnSeSystems Based on ZnTeSystems Based on CdSSystems Based on CdSeSystems Based on CdTeSystems Based on HgSSystems Based on HgSeSystems Based on HgTeIndexReferences appear at the end of each chapter.

  11. Diluted II-VI oxide semiconductors with multiple band gaps.

    Science.gov (United States)

    Yu, K M; Walukiewicz, W; Wu, J; Shan, W; Beeman, J W; Scarpulla, M A; Dubon, O D; Becla, P

    2003-12-12

    We report the realization of a new mult-band-gap semiconductor. Zn(1-y)Mn(y)OxTe1-x alloys have been synthesized using the combination of oxygen ion implantation and pulsed laser melting. Incorporation of small quantities of isovalent oxygen leads to the formation of a narrow, oxygen-derived band of extended states located within the band gap of the Zn(1-y)Mn(y)Te host. When only 1.3% of Te atoms are replaced with oxygen in a Zn0.88Mn0.12Te crystal the resulting band structure consists of two direct band gaps with interband transitions at approximately 1.77 and 2.7 eV. This remarkable modification of the band structure is well described by the band anticrossing model. With multiple band gaps that fall within the solar energy spectrum, Zn(1-y)Mn(y)OxTe1-x is a material perfectly satisfying the conditions for single-junction photovoltaics with the potential for power conversion efficiencies surpassing 50%.

  12. Diluted II-VI Oxide Semiconductors with Multiple Band Gaps

    OpenAIRE

    Yu, K.M.; Walukiewicz, W.; Wu, J; Shan, W.; Beeman, J. W.; Scarpulla, M. A.; Dubon, O. D.; Becla, P.

    2003-01-01

    We report the realization of a new multi-band-gap semiconductor. The highly mismatched alloy Zn1-yMnyOxTe1-x has been synthesized using the combination of oxygen ion implantation and pulsed laser melting. Incorporation of small quantities of isovalent oxygen leads to the formation of a narrow, oxygen-derived band of extended states located within the band gap of the Zn1-yMnyTe host. When only 1.3% of Te atoms is replaced with oxygen in a Zn0.88Mn0.12Te crystal (with band gap of 2.32 eV) the r...

  13. Kan vi forebygge en kompliceret sorgreaktion?

    DEFF Research Database (Denmark)

    Nielsen, Mette Kjærgaard; Guldin, Mai-Britt

    2017-01-01

    Pårørende til alvorligt syge patienter er i en sårbar situation og risikerer selv at blive syge. Som sundhedsprofessionelle har vi mulighed for at støtte pårørende i palliative forløb, og vi vil i denne artikel beskrive mulige prædiktorer for kompliceret sorg og depression hos den pårørende efter...

  14. Hvad skal vi med Trump-satire?

    DEFF Research Database (Denmark)

    Møller, Mette

    2017-01-01

    Trump-satire er et stort hit, og særligt en lang række satiriske videohilsner til Trump fra lande verden over får folk til at trække på smilebåndet. Men hvorfor er det så sjovt at gøre grin med Trump, og hvad kan vi bruge den politiske humor til? Link: http://videnskab.dk/kultur-samfund/hvad-skal-vi-med-trump-satire...

  15. SaVi: satellite constellation visualization

    OpenAIRE

    Wood, Lloyd

    2012-01-01

    SaVi, a program for visualizing satellite orbits, movement, and coverage, is maintained at the University of Surrey. This tool has been used for research in academic papers, and by industry companies designing and intending to deploy satellite constellations. It has also proven useful for demonstrating aspects of satellite constellations and their geometry, coverage and movement for educational and teaching purposes. SaVi is introduced and described briefly here.

  16. Statistical Tools for Fitting Models of the Population Consequences of Acoustic Disturbance to Data from Marine Mammal Populations (PCAD Tools II)

    Science.gov (United States)

    2015-09-30

    Xie, and J. McPherson. 2015. shiny: Web Application Framework for R. Claridge, D. E. 2013. Population ecology of Blainville’s beaked whales...framework for assessing the population consequences of disturbance. Methods in Ecology and Evolution:n/a–n/a. New, L. F., J. S. Clark, R. S. Condit, D...demographic and population trends. Marine Ecology Progress Series. Schick, R. S., S. D. Kraus, R. M. Rolland, A. R. Knowlton, P. K. Hamilton, H. M. Pettis, R

  17. Prevalence of Temporomandibular Disorders in an Adult Brazilian Community Population Using the Research Diagnostic Criteria (Axes I and II) for Temporomandibular Disorders (The Maringá Study).

    Science.gov (United States)

    Progiante, Patrícia Saram; Pattussi, Marcos Pascoal; Lawrence, Herenia P; Goya, Suzana; Grossi, Patrícia Krieger; Grossi, Márcio Lima

    2015-01-01

    The primary objective of this study was to assess the prevalence of temporomandibular disorders (TMDs) and comorbid factors (sleep bruxism and headaches). This study was a cross-sectional population survey in the city of Maringá, state of Paraná, Brazil. Axes I and II of the Research Diagnostic Criteria for TMD (RDC/TMD) were used for assessment of TMD signs and symptoms. The population was users of the Brazilian public health system (SUS), of both sexes, between the ages of 20 and 65 years, and not seeking treatment for TMD. The selected population (N = 1,643) was composed mostly of (a) women (65.9%), (b) married or single individuals (90.6%), (c) Caucasians (70.1%), (d) individuals aged 32.7 ± 10.3 years, (e) individuals earning a medium income (75.1%), and (f) those who had completed a high school education or higher (79.9%). According to the chronic pain grade classification (CPG) in the RDC/TMD Axis II, 36.2% of the population had some degree of TMD pain (CPG I to IV); however, only 5.1% had severe limitation due to pain (CPG III or IV). In the RDC/TMD Axis I diagnoses, 29.5% presented with muscle disorders (group I), 7.9% with disk displacements (group II), and 39.1% with other joint disorders (group III). Headaches were present in 67.9% and awake and sleep bruxism in 30% and 33.4% of the population, respectively. The prevalence of signs and symptoms of TMD was high in this population, but with low disability; however, the proportion of patients in need of treatment was much lower.

  18. Multiple parasites mediate balancing selection at two MHC class II genes in the fossorial water vole: insights from multivariate analyses and population genetics.

    Science.gov (United States)

    Tollenaere, C; Bryja, J; Galan, M; Cadet, P; Deter, J; Chaval, Y; Berthier, K; Ribas Salvador, A; Voutilainen, L; Laakkonen, J; Henttonen, H; Cosson, J-F; Charbonnel, N

    2008-09-01

    We investigated the factors mediating selection acting on two MHC class II genes (DQA and DRB) in water vole (Arvicola scherman) natural populations in the French Jura Mountains. Population genetics showed significant homogeneity in allelic frequencies at the DQA1 locus as opposed to neutral markers (nine microsatellites), indicating balancing selection acting on this gene. Moreover, almost exhaustive screening for parasites, including gastrointestinal helminths, brain coccidia and antibodies against viruses responsible for zoonoses, was carried out. We applied a co-inertia approach to the genetic and parasitological data sets to avoid statistical problems related to multiple testing. Two alleles, Arte-DRB-11 and Arte-DRB-15, displayed antagonistic associations with the nematode Trichuris arvicolae, revealing the potential parasite-mediated selection acting on DRB locus. Selection mechanisms acting on the two MHC class II genes thus appeared different. Moreover, overdominance as balancing selection mechanism was showed highly unlikely in this system.

  19. Effectiveness of Vi capsular polysaccharide typhoid vaccine among children: a cluster randomized trial in Karachi, Pakistan.

    Science.gov (United States)

    Khan, M Imran; Soofi, Sajid Bashir; Ochiai, R Leon; Habib, Mohammad Atif; Sahito, Shah Muhammad; Nizami, S Qamaruddin; Acosta, Camilo J; Clemens, John D; Bhutta, Zulfiqar A

    2012-08-03

    Typhoid fever is endemic in Karachi, with an incidence among children ranging from 170 to 450 per 100,000 child-years. Vaccination strategies are important for prevention, and the Vi capsular polysaccharide (ViCPS) vaccine has been shown to be effective in reducing the burden of typhoid fever. A cluster randomized trial was conducted in three low socioeconomic urban squatter settlements in Karachi, Pakistan between 2002 and 2007. Subsamples were followed up for assessment of immune response and adverse events after vaccination. The study participants were similar in a wide variety of socio-demographic and economic characteristics at baseline. A total of 27,231 individuals of the total target population of 51,965 in 120 clusters either received a ViCPS vaccine (13,238 [52% coverage]) or the control Hepatitis A vaccine (13,993 [53%]). Typhoid fever was diagnosed in 30 ViCPS vaccine recipients and 49 Hepatitis A vaccine recipients with an adjusted total protective effectiveness of 31% (95%CI: -28%, 63%). The adjusted total vaccine protective effectiveness was -38% (95%CI: -192%, 35%) for children aged 2-5 years and 57% (95%CI: 6%, 81%) for children 5-16 years old. The ViCPS vaccine did not confer statistically significant protection to children in the study areas, and there was a decline in antibody response 2 years post-vaccination. However, the ViCPS vaccine showed significant total protection in children 5-16 years of age, which is consistent with other studies of ViCPS vaccine conducted in India, Nepal, China and South Africa. These findings suggest that ViCPS vaccination of school-aged children will protect the children of urban, typhoid endemic areas against typhoid fever. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Soil properties influencing phytoparasitic nematode population on Chilean vineyards Propiedades del suelo que influyen en la población de nematodos fitoparásitos en viñedos de Chile

    Directory of Open Access Journals (Sweden)

    Mario Fajardo P

    2011-06-01

    Full Text Available Lifecycle of phytoparasitic nematode takes place in the rhizosphere, therefore their breeding, parasitism and mobility dynamics are inevitably influenced by the soil-root interaction, A study was performed to evaluate the influence of Vitis rootstocks to some plant parasitic nematodes under different soil conditions. Nematode populations were assessed in Vitis vinifera L. var ‘Chardonnay’ plants grafted on two rootstocks (K5BB, SO4 and ungrafted ‘Chardonnay’ as a control in three diferent alluvial soils in the central zone of Chile. Soils were two Inceptisols of the Casablanca Valley (Valparaíso Region, the first one without soil structure and with a densification zone in depth (S1 and the second one with sandy textural class (S3. A third soil was a Mollisol (S2 more structured than the others, situated on a locality of Melipilla (Metropolitan Region. The soils were characterized physically and morphologically and nematode genera were identified and counted using a dissecting microscope. ‘Chardonnay’ presented the highest population of Meloidogyne spp. on the three soil conditions but only significant in S2 soil. The population of Xiphinema spp. and Mesocriconema xenoplax were not representative enough to relate them with either soil or the different rootstocks. The amount of Meloidogyne spp. was inversely related with the sand content but positively related with the more structured soil. The stepwise regressions resulted useful when relating nematode populations with multiple soil factors.El ciclo de vida de los nematodos fitoparásitos ocurre en la rizósfera, por lo tanto, sus dinámicas de alimentación, parasitismo y movilidad están inevitablemente influenciadas por la interacción suelo-raíz. Se llevó a cabo un estudio para evaluar la respuesta de diferentes portainjertos de Vitis frente a algunas poblaciones de nematodos fitoparásitos en diferentes tipos de suelos. Se determinaron las poblaciones de nematodos fitopar

  1. Molecular and cellular analyses of HLA class II-associated susceptibility to autoimmune diseases in the Japanese population.

    Science.gov (United States)

    Nishimura, Y; Ito, H; Fujii, S; Tabata, H; Tokano, Y; Chen, Y Z; Matsuda, I; Mitsuya, H; Kira, J; Hashimoto, H; Senju, S; Matsushita, S

    2001-06-01

    Abstract It is well known that individuals who are positive for particular HLA class II alleles show a high risk of developing autoimmune diseases. HLA class II molecules expressed on antigen-presenting cells present antigenic peptides to CD4(+) T cells. Their extensive polymorphism affects the structures of peptides bound to HLA class II molecules to create individual differences in immune responses to antigenic peptides. In order to gain a better understanding of mechanisms of the association between HLA class II alleles and susceptibility to autoimmune diseases, it is important to identify self-peptides presented by disease-susceptible HLA class II molecules and triggering disease-causative T cells. Many of the autoimmune diseases are observed in all ethnic groups, whereas the incidence of diseases, clinical manifestations and disease-susceptible HLA class II alleles are different among various ethnic groups for some autoimmune diseases. These phenomena suggest that differences in autoimmune self-peptide(s) in the context of disease-susceptible HLA class II molecules may cause these differences. Therefore, comparisons among disease-susceptible HLA class II alleles, autoantigenic peptides, and clinical manifestations of autoimmune diseases in different ethnic groups would be helpful in elucidating the pathogenesis of the diseases. In this review, we describe our recent findings on (1) the uniqueness of both clinical manifestations and the HLA-linked genetic background of Asian-type (opticospinal form) multiple sclerosis, (2) the characteristics of glutamic acid decarboxylase 65 (GAD65) or β2-glycoprotein I (β2-GPI) autoreactive T cells in Japanese patients with insulin-dependent diabetes mellitus (IDDM) or anti-β2-GPI antibody-associated autoimmunity, respectively, and (3) the generation of an efficient delivery system of peptides to the HLA class II-restricted antigen presentation path-way by utilizing a class II-associated invariant chain peptide (CLIP

  2. Two founder mutations in the SEC23B gene account for the relatively high frequency of CDA II in the Italian population

    Science.gov (United States)

    Russo, Roberta; Gambale, Antonella; Esposito, Maria Rosaria; Serra, Maria Luisa; Troiano, Annaelena; De Maggio, Ilaria; Capasso, Mario; Luzzatto, Lucio; Delaunay, Jean; Tamary, Hannah; Iolascon, Achille

    2011-01-01

    Congenital Dyserythropoietic Anemia type II is an autosomal recessive disorder characterized by unique abnormalities in the differentiation of cells of the erythroid lineage. The vast majority of CDA II cases result from mutations in the SEC23B gene. To date, 53 different causative mutations have been reported in 86 unrelated cases (from the CDA II European Registry), 47 of them Italian. We have now identified SEC23B mutations in 23 additional patients, 17 Italians and 6 non-Italian Europeans. The relative allelic frequency of the mutations was then reassessed in a total of 64 Italian and 45 non-Italian unrelated patients. Two mutations, E109K and R14W, account for over one-half of the cases of CDA II in Italy. Whereas the relative frequency of E109K is similar in Italy and in the rest of Europe (and is also prevalent in Moroccan Jews), the relative frequency of R14W is significantly higher in Italy (26.3% vs. 10.7%). By haplotype analysis we demonstrated that both are founder mutations in the Italian population. By using the DMLE+ program our estimate for the age of the E109K mutation in Italian population is ≈2,200 years; whereas for the R14W mutation it is ≈3,000 years. We hypothesize that E109K may have originated in the Middle East and may have spread in the heyday of the Roman Empire. Instead, R14W may have originated in Southern Italy. The relatively high frequency of the R14W mutation may account for the known increased prevalence of CDA II in Italy. Am. J. Hematol. 86:727–732, 2011. © 2011 Wiley-Liss, Inc. PMID:21850656

  3. Selective Reduction of Cr(VI in Chromium, Copper and Arsenic (CCA Mixed Waste Streams Using UV/TiO2 Photocatalysis

    Directory of Open Access Journals (Sweden)

    Shan Zheng

    2015-02-01

    Full Text Available The highly toxic Cr(VI is a critical component in the Chromated Copper Arsenate (CCA formulations extensively employed as wood preservatives. Remediation of CCA mixed waste and discarded treated wood products is a significant challenge. We demonstrate that UV/TiO2 photocatalysis effectively reduces Cr(VI to less toxic Cr(III in the presence of arsenate, As(V, and copper, Cu(II. The rapid conversion of Cr(VI to Cr(III during UV/TiO2 photocatalysis occurs over a range of concentrations, solution pH and at different Cr:As:Cu ratios. The reduction follows pseudo-first order kinetics and increases with decreasing solution pH. Saturation of the reaction solution with argon during UV/TiO2 photocatalysis had no significant effect on the Cr(VI reduction demonstrating the reduction of Cr(VI is independent of dissolved oxygen. Reduction of Cu(II and As(V does not occur under the photocatalytic conditions employed herein and the presence of these two in the tertiary mixtures had a minimal effect on Cr(VI reduction. The Cr(VI reduction was however, significantly enhanced by the addition of formic acid, which can act as a hole scavenger and enhance the reduction processes initiated by the conduction band electron. Our results demonstrate UV/TiO2 photocatalysis effectively reduces Cr(VI in mixed waste streams under a variety of conditions.

  4. Selective reduction of Cr(VI) in chromium, copper and arsenic (CCA) mixed waste streams using UV/TiO2 photocatalysis.

    Science.gov (United States)

    Zheng, Shan; Jiang, Wenjun; Rashid, Mamun; Cai, Yong; Dionysiou, Dionysios D; O'Shea, Kevin E

    2015-02-03

    The highly toxic Cr(VI) is a critical component in the Chromated Copper Arsenate (CCA) formulations extensively employed as wood preservatives. Remediation of CCA mixed waste and discarded treated wood products is a significant challenge. We demonstrate that UV/TiO2 photocatalysis effectively reduces Cr(VI) to less toxic Cr(III) in the presence of arsenate, As(V), and copper, Cu(II). The rapid conversion of Cr(VI) to Cr(III) during UV/TiO2 photocatalysis occurs over a range of concentrations, solution pH and at different Cr:As:Cu ratios. The reduction follows pseudo-first order kinetics and increases with decreasing solution pH. Saturation of the reaction solution with argon during UV/TiO2 photocatalysis had no significant effect on the Cr(VI) reduction demonstrating the reduction of Cr(VI) is independent of dissolved oxygen. Reduction of Cu(II) and As(V) does not occur under the photocatalytic conditions employed herein and the presence of these two in the tertiary mixtures had a minimal effect on Cr(VI) reduction. The Cr(VI) reduction was however, significantly enhanced by the addition of formic acid, which can act as a hole scavenger and enhance the reduction processes initiated by the conduction band electron. Our results demonstrate UV/TiO2 photocatalysis effectively reduces Cr(VI) in mixed waste streams under a variety of conditions.

  5. The chemical abundances of the stellar populations in the Leo I and II dSph galaxies

    Science.gov (United States)

    Bosler, Tammy L.; Smecker-Hane, Tammy A.; Stetson, Peter B.

    2007-06-01

    We have obtained calcium abundances and radial velocities for 102 red giant branch (RGB) stars in the Leo I dwarf spheroidal galaxy (dSph) and 74 RGB stars in the Leo II dSph using the low-resolution spectrograph (LRIS) on the Keck I 10-m telescope. We report on the calcium abundances [Ca/H] derived from the strengths of the CaII triplet absorption lines at 8498, 8542 and 8662 Å in the stellar spectra using a new empirical CaII triplet calibration to [Ca/H]. The two galaxies have different average [Ca/H] values of -1.34 +/- 0.02 for Leo I and -1.65 +/- 0.02 for Leo II with intrinsic abundance dispersions of 1.2 and 1.0 dex, respectively. The typical random and total errors in derived abundances are 0.10 and 0.17 dex per star. For comparison to the existing literature, we also converted our CaII measurements to [Fe/H] on the scale of Carretta and Gratton (1997) though we discuss why this may not be the best determinant of metallicity; Leo I has a mean [Fe/H] = -1.34 and Leo II has a mean [Fe/H] = -1.59. The metallicity distribution function of Leo I is approximately Gaussian in shape with an excess at the metal-rich end, while that of Leo II shows an abrupt cut-off at the metal-rich end. The lower mean metallicity of Leo II is consistent with the fact that it has a lower luminosity, hence lower the total mass than Leo I; thus, the evolution of Leo II may have been affected more by mass lost in galactic winds. Our direct and independent measurement of the metallicity distributions in these dSph will allow a more accurate star-formation histories to be derived from future analysis of their colour-magnitude diagrams(CMDs). Data presented herein were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. E

  6. Adaptation and Latent Structure of the Swahili Version of Beck Depression Inventory-II in a Low Literacy Population in the Context of HIV.

    Directory of Open Access Journals (Sweden)

    Amina Abubakar

    Full Text Available We set out to adapt the Beck Depression Inventory (BDI-II in Kenya and examine its factorial structure.In the first phase we carried out in-depth interviews involving 29 adult members of the community to elicit their understanding of depression and identify aspects of the BDI-II that required adaptation. In the second phase, a modified version of BDI-II was administered to 221 adults randomly selected from the community to allow for the evaluation of its psychometric properties. In the third phase of the study we evaluated the discriminative validity of BDI-11 by comparing a randomly chosen community sample (n = 29 with caregivers of adolescents affected by HIV (n = 77.A considerable overlap between the BDI symptoms and those generated in the interviews was observed. Relevant idioms and symptoms such as 'thinking too much' and 'Kuchoka moyo (having a tired heart' were identified. The administration of the BDI had to be modified to make it suitable for the low literacy levels of our participants. Fit indices for several models (one factorial, two-factor model and a three factor model were all within acceptable range. Evidence indicated that while multidimensional models could be fitted, the strong correlations between the factors implied that a single factor model may be the best suited solution (alpha [0.89], and a significant correlation with locally identified items [r = 0.51] confirmed the good psychometric properties of the adapted BDI-II. No evidence was found to support the hypothesis that somatization was more prevalent. Lastly, caregivers of HIV affected adolescents had significantly higher scores compared to adults randomly selected from the community F(1, 121 = 23.31, p < .001 indicating the discriminative validity of the adapted BDI = II.With an adapted administration procedure, the BDI-II provides an adequate measure of depressive symptoms which can be used alongside other measures for proper diagnosis in a low literacy population.

  7. Ethical and economic considerations of rare diseases in ethnic minorities: the case of mucopolysaccharidosis VI in Colombia.

    Science.gov (United States)

    Rosselli, Diego; Rueda, Juan-David; Solano, Martha

    2012-11-01

    Mucopolysaccharidosis VI is an autosomal recessive lysosomal storage disorder associated with severe disability and premature death. The presence of a mucopolysaccharidosis-like disease in indigenous ethnic groups in Colombia can be inferred from archaeological findings. There are several indigenous patients with mucopolysaccharidosis VI currently receiving enzyme replacement therapy. We discuss the ethical and economic considerations, regarding both direct and indirect costs, of a high-cost orphan disease in a marginalised minority population in a developing country.

  8. The prognostic importance of miR-21 in stage II colon cancer: a population-based study

    DEFF Research Database (Denmark)

    Kjaer-Frifeldt, S.; Hansen, T. F.; Nielsen, B. S.

    2012-01-01

    BACKGROUND: Despite several years of research and attempts to develop prognostic models a considerable fraction of stage II colon cancer patients will experience relapse within few years from their operation. The aim of the present study was to investigate the prognostic importance of miRNA-21 (mi...

  9. Variability and connectivity of plaice populations from the Eastern North Sea to the Baltic Sea, part II. Biological evidence of population mixing

    Science.gov (United States)

    Ulrich, Clara; Hemmer-Hansen, Jakob; Boje, Jesper; Christensen, Asbjørn; Hüssy, Karin; Sun, Hailu; Clausen, Lotte Worsøe

    2017-02-01

    A multi-disciplinary study was conducted to clarify stock identity and connectivity patterns in the populations of European plaice (Pleuronectes platessa) in the Skagerrak-Kattegat transition area between the Eastern North Sea and the Baltic Sea. Five independent biological studies were carried out in parallel. Genetic markers suggested the existence of different genetic populations in the transition area. Growth backcalculation with otoliths resulted in significant although limited differences in growth rates between North Sea and Skagerrak, indicating weak differentiation or important mixing. Hydrogeographical drift modelling suggested that some North Sea juveniles could settle along the coast line of the Skagerrak and the Kattegat. Tagging data suggested that both juveniles and adult fish from the North Sea perform feeding migrations into Skagerrak in summer/autumn. Finally, survey data suggested that Skagerrak also belongs to the area distribution of North Sea plaice. The outcomes of the individual studies were then combined into an overall synthesis. The existence of some resident components was evidenced, but it was also demonstrated that North Sea plaice migrate for feeding into Skagerrak and might constitute a large share of the catches in this area. The mixing of different populations within a management area has implications for stock assessment and management. Choice must be made to either lump or split the populations, and the feasibility and constraints of both options are discussed. The outcomes of this work have directly influenced the management decisions in 2015.

  10. Vi overser hjertepatienter med ondt i livet

    DEFF Research Database (Denmark)

    Ørsted-Rasmussen, Morten; Pedersen, Susanne S.; Zwisler, Ann Dorthe Olsen

    2017-01-01

    Sundhedsvæsenet har ved en målrettet indsats sikret markant øget overlevelse efter blodprop i hjertet. Men vi risikerer at skylle det hele ud med badevandet, hvis der ikke bliver taget hånd om de psykiske følger i den kroniske fase af sygdommen......Sundhedsvæsenet har ved en målrettet indsats sikret markant øget overlevelse efter blodprop i hjertet. Men vi risikerer at skylle det hele ud med badevandet, hvis der ikke bliver taget hånd om de psykiske følger i den kroniske fase af sygdommen...

  11. Deciphering the fine nucleotide diversity of full HLA class I and class II genes in a well-documented population from sub-Saharan Africa.

    Science.gov (United States)

    Goeury, T; Creary, L E; Brunet, L; Galan, M; Pasquier, M; Kervaire, B; Langaney, A; Tiercy, J-M; Fernández-Viña, M A; Nunes, J M; Sanchez-Mazas, A

    2018-01-01

    With the aim to understand how next-generation sequencing (NGS) improves both our assessment of genetic variation within populations and our knowledge on HLA molecular evolution, we sequenced and analysed 8 HLA loci in a well-documented population from sub-Saharan Africa (Mandenka). The results of full-gene NGS-MiSeq sequencing compared with those obtained by traditional typing techniques or limited sequencing strategies showed that segregating sites located outside exon 2 are crucial to describe not only class I but also class II population diversity. A comprehensive analysis of exons 2, 3, 4 and 5 nucleotide diversity at the 8 HLA loci revealed remarkable differences among these gene regions, notably a greater variation concentrated in the antigen recognition sites of class I exons 3 and some class II exons 2, likely associated with their peptide-presentation function, a lower diversity of HLA-C exon 3, possibly related to its role as a KIR ligand, and a peculiar molecular diversity of HLA-A exon 2, revealing demographic signals. Based on full-length HLA sequences, we also propose that the most frequent DRB1 allele in the studied population, DRB1*13:04, emerged from an allelic conversion involving 3 potential alleles as donors and DRB1*11:02:01 as recipient. Finally, our analysis revealed a high occurrence of the DRB1*13:04-DQA1*05:05:01-DQB1*03:19 haplotype, possibly resulting from a selective sweep due to protection to Onchorcerca volvulus, a prevalent pathogen in West Africa. This study unveils highly relevant information on the molecular evolution of HLA genes in relation to their immune function, calling for similar analyses in other populations living in contrasting environments. © 2017 The Authors HLA: Immune Response Genetics Published by John Wiley & Sons Ltd.

  12. Deciphering the fine nucleotide diversity of full HLA class I and class II genes in a well‐documented population from sub‐Saharan Africa

    Science.gov (United States)

    Creary, L. E.; Brunet, L.; Galan, M.; Pasquier, M.; Kervaire, B.; Langaney, A.; Tiercy, J.‐M.; Fernández‐Viña, M. A.; Nunes, J. M.

    2017-01-01

    With the aim to understand how next‐generation sequencing (NGS) improves both our assessment of genetic variation within populations and our knowledge on HLA molecular evolution, we sequenced and analysed 8 HLA loci in a well‐documented population from sub‐Saharan Africa (Mandenka). The results of full‐gene NGS‐MiSeq sequencing compared with those obtained by traditional typing techniques or limited sequencing strategies showed that segregating sites located outside exon 2 are crucial to describe not only class I but also class II population diversity. A comprehensive analysis of exons 2, 3, 4 and 5 nucleotide diversity at the 8 HLA loci revealed remarkable differences among these gene regions, notably a greater variation concentrated in the antigen recognition sites of class I exons 3 and some class II exons 2, likely associated with their peptide‐presentation function, a lower diversity of HLA‐C exon 3, possibly related to its role as a KIR ligand, and a peculiar molecular diversity of HLA‐A exon 2, revealing demographic signals. Based on full‐length HLA sequences, we also propose that the most frequent DRB1 allele in the studied population, DRB1*13:04, emerged from an allelic conversion involving 3 potential alleles as donors and DRB1*11:02:01 as recipient. Finally, our analysis revealed a high occurrence of the DRB1*13:04‐DQA1*05:05:01‐DQB1*03:19 haplotype, possibly resulting from a selective sweep due to protection to Onchorcerca volvulus, a prevalent pathogen in West Africa. This study unveils highly relevant information on the molecular evolution of HLA genes in relation to their immune function, calling for similar analyses in other populations living in contrasting environments. PMID:29160618

  13. Natural history of pulmonary function in collagen VI-related myopathies.

    Science.gov (United States)

    Foley, A Reghan; Quijano-Roy, Susana; Collins, James; Straub, Volker; McCallum, Michelle; Deconinck, Nicolas; Mercuri, Eugenio; Pane, Marika; D'Amico, Adele; Bertini, Enrico; North, Kathryn; Ryan, Monique M; Richard, Pascale; Allamand, Valérie; Hicks, Debbie; Lamandé, Shireen; Hu, Ying; Gualandi, Francesca; Auh, Sungyoung; Muntoni, Francesco; Bönnemann, Carsten G

    2013-12-01

    phenotypically. These findings improve our knowledge of the natural history of the collagen VI-related myopathies, enabling proactive optimization of care and preparing this patient population for clinical trials.

  14. Stellar Population and Star Formation History of the Distant Galactic H II Regions NGC 2282 and Sh2-149

    Science.gov (United States)

    Dutta, S.; Mondal, S.; Jose, J.; Das, R. K.

    2017-06-01

    We present here the recent results on two distant Galactic H II regions, namely NGC 2282 and Sh2-149, obtained with multiwavelength observations. Our optical spectroscopic analysis of the bright sources have been used to identify the massive members, and to derive the fundamental parameters such as age and distance of these regions. Using IR color-color criteria and Hα-emission properties, we have identified and classified the candidate young stellar objects (YSOs) in these regions. The 12CO(1-0) continuum maps along with the K-band extinction maps, and spatial distribution of YSOs are used to investigate the structure and morphology of the molecular cloud associated with these H II regions. Overall analysis of these regions suggests that the star formation occurs at the locations of the denser gas, and we also find possible evidences of the induced star formation due to the feedback from massive stars to its surrounding molecular medium.

  15. Genetic parameters for agronomic characteristics. II. Intermediate and advanced stages in a true potato seed breeding population

    National Research Council Canada - National Science Library

    Ortiz, Rodomiro; Golmirzaie, Ali M

    2003-01-01

    The aim of this research was to determine the genetic variation available in some important characteristics for true potato seed breeding in intermediate and advanced stages of a breeding population...

  16. Disentangling the Galactic Halo with APOGEE. II. Chemical and Star Formation Histories for the Two Distinct Populations

    Science.gov (United States)

    Fernández-Alvar, Emma; Carigi, Leticia; Schuster, William J.; Hayes, Christian R.; Ávila-Vergara, Nancy; Majewski, Steve R.; Allende Prieto, Carlos; Beers, Timothy C.; Sánchez, Sebastián F.; Zamora, Olga; García-Hernández, Domingo Aníbal; Tang, Baitian; Fernández-Trincado, José G.; Tissera, Patricia; Geisler, Douglas; Villanova, Sandro

    2018-01-01

    The formation processes that led to the current Galactic stellar halo are still under debate. Previous studies have provided evidence for different stellar populations in terms of elemental abundances and kinematics, pointing to different chemical and star formation histories (SFHs). In the present work, we explore, over a broader range in metallicity (-2.2Experiment (APOGEE). We aim to infer signatures of the initial mass function (IMF) and the SFH from the two α-to-iron versus iron abundance chemical trends for the most APOGEE-reliable α-elements (O, Mg, Si, and Ca). Using simple chemical-evolution models, we infer the upper mass limit (M up) for the IMF and the star formation rate, and its duration for each population. Compared with the low-α population, we obtain a more intense and longer-lived SFH, and a top-heavier IMF for the high-α population.

  17. Pneumothoraces in collagen VI-related dystrophy: a case series and recommendations for management

    Directory of Open Access Journals (Sweden)

    Kristin L. Fraser

    2017-06-01

    Full Text Available Collagen VI-related dystrophy (collagen VI-RD is a rare neuromuscular condition caused by mutations in the COL6A1, COL6A2 or COL6A3 genes. The phenotypic spectrum includes early-onset Ullrich congenital muscular dystrophy, adult-onset Bethlem myopathy and an intermediate phenotype. The disorder is characterised by distal hyperlaxity and progressive muscle weakness, joint contractures and respiratory insufficiency. Respiratory insufficiency is attributed to chest wall contractures, scoliosis, impaired diaphragmatic function and intercostal muscle weakness. To date, intrinsic parenchymal lung disease has not been implicated in the inevitable respiratory decline of these patients. This series focuses on pneumothorax, an important but previously under-recognised disease manifestation of collagen VI-RD. We describe two distinct clinical presentations within collagen VI-RD patients with pneumothorax. The first cohort consists of neonates and children with a single pneumothorax in the setting of large intrathoracic pressure changes. The second group is made up of adult patients with recurrent pneumothoraces, associated with chest computed tomography scan evidence of parenchymal lung disease. We describe treatment challenges in this unique population with respect to expectant observation, tube thoracostomy and open pleurodesis. Based on this experience, we offer recommendations for early identification of lung disease in collagen VI-RD and definitive intervention.

  18. Validation of the Preverbal Visual Assessment (PreViAs) questionnaire.

    Science.gov (United States)

    García-Ormaechea, Inés; González, Inmaculada; Duplá, María; Andres, Eva; Pueyo, Victoria

    2014-10-01

    Visual cognitive integrative functions need to be evaluated by a behavioral assessment, which requires an experienced evaluator. The Preverbal Visual Assessment (PreViAs) questionnaire was designed to evaluate these functions, both in general pediatric population or in children with high risk of visual cognitive problems, through primary caregivers' answers. We aimed to validate the PreViAs questionnaire by comparing caregiver reports with results from a comprehensive clinical protocol. A total of 220 infants (visual development, as determined by the clinical protocol. Their primary caregivers completed the PreViAs questionnaire, which consists of 30 questions related to one or more visual domains: visual attention, visual communication, visual-motor coordination, and visual processing. Questionnaire answers were compared with results of behavioral assessments performed by three pediatric ophthalmologists. Results of the clinical protocol classified 128 infants as having normal visual maturation, and 92 as having abnormal visual maturation. The specificity of PreViAs questionnaire was >80%, and sensitivity was 64%-79%. More than 80% of the infants were correctly classified, and test-retest reliability exceeded 0.9 for all domains. The PreViAs questionnaire is useful to detect abnormal visual maturation in infants from birth to 24months of age. It improves the anamnesis process in infants at risk of visual dysfunctions. Copyright © 2014. Published by Elsevier Ireland Ltd.

  19. BIOSORPTION OF CHROMIUM (VI) USING IMMOBILIZED ...

    African Journals Online (AJOL)

    USER

    2016-05-20

    May 20, 2016 ... water and air. It affects the growth of flora and fauna which in turn affect human health negatively. Chromium could also bio-accumulate in plants and animals and this becomes ... The sorption kinetic models of Cr (VI) onto the biosorbents were examined with ... bulk density, moisture and ash contents.

  20. 76 FR 60593 - Title VI; Proposed Circular

    Science.gov (United States)

    2011-09-29

    ... for FTA staff to make oral presentations about the two proposed Circulars and allow attendees an... proposed Circular would incorporate lessons learned from triennial reviews, discretionary Title VI... Implementation Plan for Limited English Proficient (LEP) persons now contains a summary of the DOT LEP guidance...

  1. Prospek pengembangan industri perkulitan pada pelita VI

    OpenAIRE

    D. Karyadi

    1995-01-01

    The leather industry is one of the strong competitive industry, as it comes from renewable natural resources. Therefore, the leather industry has good prospect to develop at the Pelita VI to be the industrial products export competitive. To develop leather industry and leather products should be given closed attention and well managed, especially concerning raw material supply, quality and leather waste treatment.

  2. Resúmenes Presentaciones Orales VI ECAP

    OpenAIRE

    Vargas Arana, Editor Gabriel

    2016-01-01

    En este artículo se pueden encontrar los resúmenes de las presentaciones orales del VI Ecuentro Científico de la Amazonía Peruana, desarrollado el 27 y 28 de cotubre de 2015 en la ciudad de Iquitos, Perú.

  3. Vi har selv designet naturens love

    DEFF Research Database (Denmark)

    Bentzen, Martin Mose

    2014-01-01

    ForskerZonenNaturlovene er universelt gyldige i de flestes øjne. De gælder altid, uanset hvad vi tænker. Men dette billede står ikke uimodsagt i videnskabsfilosofien, og der er meget, der tyder på, at det ikke er specielt empirisk korrekt...

  4. Chromium(VI) bioremediation by probiotics.

    Science.gov (United States)

    Younan, Soraia; Sakita, Gabriel Z; Albuquerque, Talita R; Keller, Rogéria; Bremer-Neto, Hermann

    2016-09-01

    Chromium is a common mineral in the earth's crust and can be released into the environment from anthropogenic sources. Intake of hexavalent chromium (Cr(VI)) through drinking water and food causes toxic effects, leading to serious diseases, and is a commonly reported environmental problem. Microorganisms can mitigate or prevent the toxic effects caused by heavy metals in addition to having effective resistance mechanisms to prevent cell damage and bind to these metals, sequestering them from the cell surface and removing them from the body. Species of Lactobacillus, Streptococcus, Bacillus and Bifidobacterium present in the human mouth and gut and in fermented foods have the ability to bind and detoxify some of these substances. This review address the primary topics related to Cr(VI) poisoning in animals and humans and the use of probiotics as a way to mitigate or prevent the toxic effects caused by Cr(VI). Further advances in the genetic knowledge of such microorganisms may lead to discoveries which will clarify the most active microorganisms that act as bioprotectants in bodies exposed to Cr(VI) and are an affordable option for people and animals intoxicated by the oral route. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  5. 77 FR 52116 - Title VI; Final Circular

    Science.gov (United States)

    2012-08-28

    ... enforcement of Title VI disparate impact regulations, it did not undermine the validity of those regulations... streamlined this process. We have modified the definition of ``disparate impact'' for clarity. We decline to... process reengineering. In response, FTA will review the public engagement plan and its implementation when...

  6. Hvem er vi? Hvem er de?

    DEFF Research Database (Denmark)

    Kryger, Niels

    2016-01-01

    Kommentaren tager afsæt i initiativer i de pædagogiske faglige foreninger i Europa EERA) og i Norden (NERA) og argumenterer for at det er forpligtelse for os som nordiske og europæiske pædagogiske forskere at gå op imod de stadigt mere ekskluderende vi-konstruktioner, som er blevet formuleret i for...

  7. Permeable Reactive Biobarriers for In Situ Cr(VI) Reduction: Bench Scale Tests Using Cellulomonas sp. Strain ES6

    Energy Technology Data Exchange (ETDEWEB)

    Sridhar Viamajala; Brent M. Peyton; Robin Gerlach; Vaideeswaran; William A. Apel; James N. Petersen

    2008-12-01

    Chromate (Cr(VI)) reduction studies were performed in bench scale flow columns using the fermentative subsurface isolate Cellulomonas sp. strain ES6. In these tests, columns packed with either quartz sand or hydrous ferric oxide (HFO)-coated quartz sand, were inoculated with strain ES6 and fed nutrients to stimulate growth before nutrient-free Cr(VI) solutions were injected. Results show that in columns containing quartz sand, a continuous inflow of 2 mg/L Cr(VI) was reduced to below detection limits in the effluent for durations of up to 5.7 residence times after nutrient injection was discontinued proving the ability of strain ES6 to reduce chromate in the absence of an external electron donor. In the HFO-containing columns, Cr(VI) reduction was significantly prolonged and effluent Cr(VI) concentrations remained below detectable levels for periods of up to 66 residence times after nutrient injection was discontinued. Fe was detected in the effluent of the HFO-containing columns throughout the period of Cr(VI) removal indicating that the insoluble Fe(III) bearing solids were being continuously reduced to form soluble Fe(II) resulting in prolonged abiotic Cr(VI) reduction. Thus, growth of Cellulomonas within the soil columns resulted in formation of permeable reactive barriers that could reduce Cr(VI) and Fe(III) for extended periods even in the absence of external electron donors. Other bioremediation systems employing Fe(II)-mediated reactions require a continuous presence of external nutrients to regenerate Fe(II). After depletion of nutrients, contaminant removal within these systems occurs by reaction with surface-associated Fe(II) that can rapidly become inaccessible due to formation of crystalline Fe-minerals or other precipitates. The ability of fermentative organisms like Cellulomonas to reduce metals without continuous nutrient supply in the subsurface offers a viable and economical alternative technology for in situ remediation of Cr(VI

  8. Permeable reactive biobarriers for in situ Cr(VI) reduction: bench scale tests using Cellulomonas sp. strain ES6.

    Science.gov (United States)

    Viamajala, Sridhar; Peyton, Brent M; Gerlach, Robin; Sivaswamy, Vaideeswaran; Apel, William A; Petersen, James N

    2008-12-15

    Chromate (Cr(VI)) reduction studies were performed in bench scale flow columns using the fermentative subsurface isolate Cellulomonas sp. strain ES6. In these tests, columns packed with either quartz sand or hydrous ferric oxide (HFO)-coated quartz sand, were inoculated with strain ES6 and fed nutrients to stimulate growth before nutrient-free Cr(VI) solutions were injected. Results show that in columns containing quartz sand, a continuous inflow of 2 mg/L Cr(VI) was reduced to below detection limits in the effluent for durations of up to 5.7 residence times after nutrient injection was discontinued proving the ability of strain ES6 to reduce chromate in the absence of an external electron donor. In the HFO-containing columns, Cr(VI) reduction was significantly prolonged and effluent Cr(VI) concentrations remained below detectable levels for periods of up to 66 residence times after nutrient injection was discontinued. Fe was detected in the effluent of the HFO-containing columns throughout the period of Cr(VI) removal indicating that the insoluble Fe(III) bearing solids were being continuously reduced to form soluble Fe(II) resulting in prolonged abiotic Cr(VI) reduction. Thus, growth of Cellulomonas within the soil columns resulted in formation of permeable reactive barriers that could reduce Cr(VI) and Fe(III) for extended periods even in the absence of external electron donors. Other bioremediation systems employing Fe(II)-mediated reactions require a continuous presence of external nutrients to regenerate Fe(II). After depletion of nutrients, contaminant removal within these systems occurs by reaction with surface-associated Fe(II) that can rapidly become inaccessible due to formation of crystalline Fe-minerals or other precipitates. The ability of fermentative organisms like Cellulomonas to reduce metals without continuous nutrient supply in the subsurface offers a viable and economical alternative technology for in situ remediation of Cr(VI

  9. Kinetic and Thermodynamic Studies of the Adsorption of Cr(VI) onto ...

    African Journals Online (AJOL)

    NICO

    Department of Chemistry, College of Natural Sciences, Jimma University, P.O. Box 378, Jimma, Ethiopia. Received 19 ..... and Ni (II).24,27. 3.4. Effect of Initial Chromium (VI) Concentration. The uptake of chromium on the adsorbents was studied at optimal pH values, the adsorbent dose of 0.5 g (in 30 mL solution), shaking ...

  10. How did Japanese rural dwellers become rapidly healthier in the two decades following World War II?: Examining the diverse policy interventions that improved the population's health.

    Science.gov (United States)

    Yuasa, Motoyuki

    2017-01-01

    Objective During the two decades following Japan's World War II surrender in 1945, tremendous improvement in the population's health was observed, particularly in infant mortality and life expectancy. How did Japanese rural dwellers achieve such remarkable health improvement during this relatively short time span while its economy remained heavily damaged following the war? While the efforts from government-driven public health strategies and programs are well known, relatively little is known about the contributions of policies in non-health sectors. Therefore, the main aim is to verify, using literature based sources, whether non-health sectors contributed to the betterment of the population's health in addition to the public health sector policies.Hypotheses Synergistic efforts of diverse interventions from different policies and programs likely catalyzed the drastic health improvement observed in the Japanese population in the two decades after World War II. The Ministry of Health and Welfare, for example, implemented programs to provide health care services. These are thought to have contributed directly to reducing maternal and child mortality, as well as tuberculosis-related mortality. Additionally, the Ministry of Agriculture and Forestry carried out a nationwide livelihood improvement program to enhance individual and family lifestyles, improve indoor and outdoor environments, and strengthen social solidarity. The ministry also attempted to generate income stability for farmers through an agricultural improvement program to ensure allocation of household income to family health. The Ministry of Education also had an initiative to disseminate the concepts of democracy and rational thought to the Japanese population through a social education program. Through these efforts, superstition and pre-modern customs were reduced, and subsequently health awareness increased, leading to an improvement in the population's health.Conclusion The public health

  11. Cloning and expression of a Vi mimotope of Salmonella enterica ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-09-15

    Sep 15, 2009 ... A recombinant His-Vi protein of Salmonella enterica serovar Typhi was successfully constructed and cloned into an expression vector ... recombinant protein can be used to detect specific anti-Vi antibody produced by typhoid patients. Overall, the His-Vi ... E-mail: khchua@um.edu.my. Tel.:603-. 79676607.

  12. Bioreduction of Cr (VI) by potent novel chromate resistant alkaliphilic ...

    African Journals Online (AJOL)

    Isolation of Cr (VI) resistant alkaliphilic bacteria from sediment and water samples collected from Wadi Natrun hypersaline Soda lakes (located in northern Egypt), resulted in isolation of several alkaliphilic bacterial strains that can tolerate up to 2.94 g/l of Cr (VI) in alkaline medium. However, with increasing Cr (VI) ...

  13. HLA Class I and Class II Conserved Extended Haplotypes and Their Fragments or Blocks in Mexicans: Implications for the Study of Genetic Diversity in Admixed Populations

    Science.gov (United States)

    Ohashi, Marina; Lebedeva, Tatiana; Acuña-Alonzo, Víctor; Yunis, María; Granados-Montiel, Julio; Cruz-Lagunas, Alfredo; Vargas-Alarcón, Gilberto; Rodríguez-Reyna, Tatiana S.; Fernandez-Viña, Marcelo; Granados, Julio; Yunis, Edmond J.

    2013-01-01

    Major histocompatibility complex (MHC) genes are highly polymorphic and informative in disease association, transplantation, and population genetics studies with particular importance in the understanding of human population diversity and evolution. The aim of this study was to describe the HLA diversity in Mexican admixed individuals. We studied the polymorphism of MHC class I (HLA-A, -B, -C), and class II (HLA-DRB1, -DQB1) genes using high-resolution sequence based typing (SBT) method and we structured the blocks and conserved extended haplotypes (CEHs) in 234 non-related admixed Mexican individuals (468 haplotypes) by a maximum likelihood method. We found that HLA blocks and CEHs are primarily from Amerindian and Caucasian origin, with smaller participation of African and recent Asian ancestry, demonstrating a great diversity of HLA blocks and CEHs in Mexicans from the central area of Mexico. We also analyzed the degree of admixture in this group using short tandem repeats (STRs) and HLA-B that correlated with the frequency of most probable ancestral HLA-C/−B and -DRB1/−DQB1 blocks and CEHs. Our results contribute to the analysis of the diversity and ancestral contribution of HLA class I and HLA class II alleles and haplotypes of Mexican admixed individuals from Mexico City. This work will help as a reference to improve future studies in Mexicans regarding allotransplantation, immune responses and disease associations. PMID:24086347

  14. Variability and connectivity of plaice populations from the Eastern North Sea to the Baltic Sea, part II. Biological evidence of population mixing

    DEFF Research Database (Denmark)

    Ulrich, Clara; Hansen, Jakob Hemmer; Boje, Jesper

    2016-01-01

    in parallel. Genetic markers suggested the existence of different genetic populations in the transition area. Growth backcalculation with otoliths resulted in significant although limited differences in growth rates between North Sea and Skagerrak, indicating weak differentiation or important mixing....... Hydrogeographical drift modelling suggested that some North Sea juveniles could settle along the coast line of the Skagerrak and the Kattegat. Tagging data suggested that both juveniles and adult fish from the North Sea perform feeding migrations into Skagerrak in summer/autumn. Finally, survey data suggested...... that Skagerrak also belongs to the area distribution of North Sea plaice. The outcomes of the individual studies were then combined into an overall synthesis. The existence of some resident components was evidenced, but it was also demonstrated that North Sea plaice migrate for feeding into Skagerrak and might...

  15. Morphological heterogeneity of layer VI neurons in mouse barrel cortex.

    Science.gov (United States)

    Chen, Chia-Chien; Abrams, Svetlana; Pinhas, Alex; Brumberg, Joshua C

    2009-02-20

    Understanding the basic neuronal building blocks of the neocortex is a necessary first step toward comprehending the composition of cortical circuits. Neocortical layer VI is the most morphologically diverse layer and plays a pivotal role in gating information to the cortex via its feedback connection to the thalamus and other ipsilateral and callosal corticocortical connections. The heterogeneity of function within this layer is presumably linked to its varied morphological composition. However, so far, very few studies have attempted to define cell classes in this layer using unbiased quantitative methodologies. Utilizing the Golgi staining technique along with the Neurolucida software, we recontructed 222 cortical neurons from layer VI of mouse barrel cortex. Morphological analyses were performed by quantifying somatic and dendritic parameters, and, by using principal component and cluster analyses, we quantitatively categorized neurons into six distinct morphological groups. Additional systematic replication on a separate population of neurons yielded similar results, demonstrating the consistency and reliability of our categorization methodology. Subsequent post hoc analyses of dendritic parameters supported our neuronal classification scheme. Characterizing neuronal elements with unbiased quantitative techniques provides a framework for better understanding structure-function relationships within neocortical circuits in general.

  16. Selective Reduction of Cr(VI) in Chromium, Copper and Arsenic (CCA) Mixed Waste Streams Using UV/TiO2 Photocatalysis

    OpenAIRE

    Shan Zheng; Wenjun Jiang; Mamun Rashid; Yong Cai; Dionysios D. Dionysiou; Kevin E. O'Shea

    2015-01-01

    The highly toxic Cr(VI) is a critical component in the Chromated Copper Arsenate (CCA) formulations extensively employed as wood preservatives. Remediation of CCA mixed waste and discarded treated wood products is a significant challenge. We demonstrate that UV/TiO2 photocatalysis effectively reduces Cr(VI) to less toxic Cr(III) in the presence of arsenate, As(V), and copper, Cu(II). The rapid conversion of Cr(VI) to Cr(III) during UV/TiO2 photocatalysis occurs over a range of concentrations,...

  17. Contemporary Issues in Medicine--Medical Informatics and Population Health: Report II of the Medical School Objectives Project.

    Science.gov (United States)

    Academic Medicine, 1999

    1999-01-01

    The report of the Association of American Medical Colleges' Medical School Objectives Program presents the work of two expert panels. One, on medical informatics, identified five important physician roles: lifelong learner, clinician, educator, researcher, and manager. Another panel established a definition for "population health…

  18. Adaptation and Latent Structure of the Swahili Version of Beck Depression Inventory-II in a Low Literacy Population in the Context of HIV.

    Science.gov (United States)

    Abubakar, Amina; Kalu, Raphael Birya; Katana, Khamis; Kabunda, Beatrice; Hassan, Amin S; Newton, Charles R; Van de Vijver, Fons

    2016-01-01

    We set out to adapt the Beck Depression Inventory (BDI)-II in Kenya and examine its factorial structure. In the first phase we carried out in-depth interviews involving 29 adult members of the community to elicit their understanding of depression and identify aspects of the BDI-II that required adaptation. In the second phase, a modified version of BDI-II was administered to 221 adults randomly selected from the community to allow for the evaluation of its psychometric properties. In the third phase of the study we evaluated the discriminative validity of BDI-11 by comparing a randomly chosen community sample (n = 29) with caregivers of adolescents affected by HIV (n = 77). A considerable overlap between the BDI symptoms and those generated in the interviews was observed. Relevant idioms and symptoms such as 'thinking too much' and 'Kuchoka moyo (having a tired heart)' were identified. The administration of the BDI had to be modified to make it suitable for the low literacy levels of our participants. Fit indices for several models (one factorial, two-factor model and a three factor model) were all within acceptable range. Evidence indicated that while multidimensional models could be fitted, the strong correlations between the factors implied that a single factor model may be the best suited solution (alpha [0.89], and a significant correlation with locally identified items [r = 0.51]) confirmed the good psychometric properties of the adapted BDI-II. No evidence was found to support the hypothesis that somatization was more prevalent. Lastly, caregivers of HIV affected adolescents had significantly higher scores compared to adults randomly selected from the community F(1, 121) = 23.31, p depressive symptoms which can be used alongside other measures for proper diagnosis in a low literacy population.

  19. Heavy Metal Resistances and Chromium Removal of a Novel Cr(VI)-Reducing Pseudomonad Strain Isolated from Circulating Cooling Water of Iron and Steel Plant.

    Science.gov (United States)

    Zhang, Jian-Kun; Wang, Zhen-Hua; Ye, Yun

    2016-12-01

    Three bacterial isolates, GT2, GT3, and GT7, were isolated from the sludge and water of a circulating cooling system of iron and steel plant by screening on Cr(VI)-containing plates. Three isolates were characterized as the members of the genus Pseudomonas on the basis of phenotypic characteristics and 16S rRNA sequence analysis. All isolates were capable of resisting multiple antibiotics and heavy metals. GT7 was most resistant to Cr(VI), with a minimum inhibitory concentration (MIC) of 6.5 mmol L(-1). GT7 displayed varied rates of Cr(VI) reduction in M2 broth, which was dependent on pH, initial Cr(VI) concentration, and inoculating dose. Total chromium analysis revealed that GT7 could remove a part of chromium from the media, and the maximum rate of chromium removal was up to 40.8 %. The Cr(VI) reductase activity of GT7 was mainly associated with the soluble fraction of cell-free extracts and reached optimum at pH 6.0∼8.0. The reductase activity was apparently enhanced by external electron donors and Cu(II), whereas it was seriously inhibited by Hg(II), Cd(II), and Zn(II). The reductase showed a K m of 74 μmol L(-1) of Cr(VI) and a V max of 0.86 μmol of Cr(VI) min(-1) mg(-1) of protein. The results suggested that GT7 could be a promising candidate for in situ bioremediation of Cr(VI).

  20. [Hungarian Diet and Nutritional Status Survey -- the OTAP2009 study. II. Energy and macronutrient intake of the Hungarian population].

    Science.gov (United States)

    Sarkadi Nagy, Eszter; Bakacs, Márta; Illés, Eva; Zentai, Andrea; Lugasi, Andrea; Martos, Eva

    2012-07-08

    The Hungarian Diet and Nutritional Status Survey is the fourth in the row of the Hungarian national dietary surveys conducted by the Institute for Food and Nutrition Science. The present study was performed to provide valid, up-to-date data on energy and nutrient intakes and dietary habits of the Hungarian adult population. The energy and nutrient intakes were calculated on validated three-day dietary records of a representative sample by age and gender of the Hungarian population aged ≥ 18 ys. The energy percentage of fat was too high (39 E% for men and 36 E% for women), that of carbohydrate was too low (45 E% for men and 48 E% for women), whereas that of protein met the recommendation (15 E% for men and 15 E% for women). Reduction of the nutritional risk factors would greatly reduce the mortality and morbidity rates of nutrition-related diseases.

  1. Kuidas tagada lapserööviasjas tehtud kohtulahendi täitmine? Haagi 1980. aasta lapseröövi konventsiooni kohaldamise praktiline külg / Maarja Torga

    Index Scriptorium Estoniae

    Torga, Maarja, 1984-

    2015-01-01

    Lapseröövi suhtes tsiviilõiguse kohaldamise rahvusvahelisest konventsioonist (RT II 2001, 6, 33). Nõuded lapse tagastamist otsustava kohtulahendi resolutsioonile ja lapse tagastamise täitemenetlusele

  2. Changes in size of populations and level of conflict since World War II: implications for health and health services.

    Science.gov (United States)

    Garfield, Richard M; Polonsky, Jonathan; Burkle, Frederick M

    2012-10-01

    Armed conflicts include declared cross-border and internal wars and political, ethnic, and religious hostilities. The number of conflicts worldwide and their level of intensity have varied widely during the last 5 decades. Tracking conflicts throughout this period has focused predominantly on the number of individuals killed or displaced from these hostilities through count-based estimation systems, or establishing rates of excess mortality from demographic surveys. This report focuses on people living in areas with conflict by applying an estimated level of conflict intensity to data on the population of each territory with hostilities during 1946 to 2007. Data from the Uppsala Conflict Data Program/Peace Research Institute Oslo (UCDP/PRIO) Armed Conflict project database on 324 conflicts of any type in countries with populations greater than 500 000 were combined with conflict-intensity estimates from the Center for Systemic Peace and population data from the US Census Bureau International Data Base. More than half a billion people lived in conflict-affected areas in 2007. An increasing proportion of those affected by conflict lived in early postconflict areas, where hostilities were judged or declared during the last 5 years. In the past 2 decades, the average intensity of conflict among those living in areas with a current conflict has gradually declined. A burgeoning population lives in areas where conflict has recently ended, yet most of the world's large-scale medical responses to emergencies focus on high-intensity conflicts. Effective emergency and reconstruction activities in the health sector will depend on reorganizing services to increasingly focus on and transition to low-level and postconflict environments.

  3. Structure and dynamics of galaxies with a low surface-brightness disc - II. Stellar populations of bulges

    Science.gov (United States)

    Morelli, L.; Corsini, E. M.; Pizzella, A.; Dalla Bontà, E.; Coccato, L.; Méndez-Abreu, J.; Cesetti, M.

    2012-06-01

    We present the radial profiles of the Hβ, Mg and Fe line-strength indices for a sample of eight spiral galaxies with a low-surface-brightness stellar disc and a bulge. The correlations between the central values of the line-strength indices and velocity dispersion are consistent with those known for early-type galaxies and bulges of high-surface-brightness galaxies. The age, metallicity and α/Fe enhancement of the stellar populations in the bulge-dominated region are obtained using stellar population models with variable element abundance ratios. Almost all the sample bulges are characterized by a young stellar population, ongoing star formation and a solar α/Fe enhancement. Their metallicity spans from high to subsolar values. No significant gradient in age and α/Fe enhancement is measured, whereas a negative metallicity gradient is found only in a few cases. These properties suggest that a pure dissipative collapse cannot explain the formation of all the sample bulges and that other phenomena, such as mergers or acquisition events, need to be invoked. Such a picture is also supported by the lack of a correlation between the central value and the gradient of the metallicity in bulges with very low metallicity. The stellar populations of the bulges hosted by low-surface-brightness discs share many properties with those of high-surface-brightness galaxies. Therefore, they are likely to have common formation scenarios and evolution histories. A strong interplay between bulges and discs is ruled out by the fact that, in spite of being hosted by discs with extremely different properties, the bulges of low- and high-surface-brightness discs are remarkably similar. Based on observations made with European Southern Observatory telescopes at the La Silla Paranal Observatory under programmes 76.B-0375 and 80.B-00754.

  4. On the Spatially Resolved Star Formation History in M51. II. X-Ray Binary Population Evolution

    Science.gov (United States)

    Lehmer, B. D.; Eufrasio, R. T.; Markwardt, L.; Zezas, A.; Basu-Zych, A.; Fragos, T.; Hornschemeier, A. E.; Ptak, A.; Tzanavaris, P.; Yukita, M.

    2017-12-01

    We present a new technique for empirically calibrating how the X-ray luminosity function (XLF) of X-ray binary (XRB) populations evolves following a star formation event. We first utilize detailed stellar population synthesis modeling of far-UV-to-far-IR photometry of the nearby face-on spiral galaxy M51 to construct maps of the star formation histories (SFHs) on subgalactic (≈400 pc) scales. Next, we use the ≈850 ks cumulative Chandra exposure of M51 to identify and isolate 2–7 keV detected point sources within the galaxy, and we use our SFH maps to recover the local properties of the stellar populations in which each X-ray source is located. We then divide the galaxy into various subregions based on their SFH properties (e.g., star formation rate (SFR) per stellar mass ({M}\\star ) and mass-weighted stellar age) and group the X-ray point sources according to the characteristics of the regions in which they are found. Finally, we construct and fit a parameterized XLF model that quantifies how the XLF shape and normalization evolves as a function of the XRB population age Our best-fit model indicates that the XRB XLF per unit stellar mass declines in normalization, by ∼3–3.5 dex, and steepens in slope from ≈10 Myr to ≈10 Gyr. We find that our technique recovers results from past studies of how XRB XLFs and XRB luminosity scaling relations vary with age and provides a self-consistent picture for how XRB XLFs evolve with age.

  5. Exploration of the new class of layered III-VI Diluted Magnetic Semiconductors (DMS)

    Science.gov (United States)

    Pekarek, Thomas; Miotkowski, I.; Ramdas, A. K.

    2014-03-01

    We have explored a new class of quasi-two-dimensional III-VI Diluted Magnetic Semiconductors (DMS) exhibiting a wide range of magnetic behavior. Several are good candidates for potential device applications. In In1-xMnxSe, we found a remarkably large thermal hysteresis (Delta T is approximately 200 K) extending up to room temperature. This is an important material because a typical thermal hysteresis in most materials has a Delta T approximately 20 K occurring well below room temperature. The thermal hysteresis is also seen in transport measurements for In1-xMnxSe. To date, we have found good agreement between experiment and theory for the 1st three III-VI DMS systems (In1-xMnxSe, In1-xMnxS, and Ga1-xMnxS). Ga1-xFexSe is unique amount the III-VI DMS exhibiting substantial magnetic anisotropy. In Ga1-xMnxS, we have found a spin glass transition and critical exponents (γ = 4.0, β = 0.8, and δ = 5.5) that are in agreement with the theory. We surprisingly found that the spin glass transition in the 2-D IIIVI DMS similar to spin glass in 3-D II-VI DMS. [This research was supported by the UNF Terry Presidential Professorship, a Purdue University Academic Reinvestment Program and by the National Science Foundation (NSF) Grant Nos. DMR-07-06593 and DMR-04-05082.

  6. Noget vi kan tro på

    DEFF Research Database (Denmark)

    Olsen, Jan Brødslev

    2016-01-01

    Situationen er alvorlig. Verden står over for enorme udfordringer med pres på naturressourcer, klima, befolkningsvækst, flygtninge og konflikter. Det er svært at se, hvordan disse problemer kan håndteres inden for den nuværende menneskelige bevidstheds rammer. Vi må derfor foretage et bevidstheds......Situationen er alvorlig. Verden står over for enorme udfordringer med pres på naturressourcer, klima, befolkningsvækst, flygtninge og konflikter. Det er svært at se, hvordan disse problemer kan håndteres inden for den nuværende menneskelige bevidstheds rammer. Vi må derfor foretage et...

  7. Hvad skal vi med Trump-satire?

    DEFF Research Database (Denmark)

    Møller, Mette

    2017-01-01

    Trump-satire er et stort hit, og særligt en lang række satiriske videohilsner til Trump fra lande verden over får folk til at trække på smilebåndet. Men hvorfor er det så sjovt at gøre grin med Trump, og hvad kan vi bruge den politiske humor til?......Trump-satire er et stort hit, og særligt en lang række satiriske videohilsner til Trump fra lande verden over får folk til at trække på smilebåndet. Men hvorfor er det så sjovt at gøre grin med Trump, og hvad kan vi bruge den politiske humor til?...

  8. CPE OF URANIUM (VI USING IONIC LIQUID

    Directory of Open Access Journals (Sweden)

    SANAA NAÏT-TAHAR

    2016-07-01

    Full Text Available Cloud point extraction (CPE was used to extract uranium (VI from an aqueous solution in acetate media. The methodology used is based on the formation of uranyl-ionic liquid (I complexes and uranyl-D2EHPA soluble in a micellar phase of non-ionic surfactant (Triton X-100. The uranium (VI complexes are then extracted into the surfactant-rich phase at ambient temperature. The ionic liquid (IL used as a chelating agent was synthesized and characterized in this study. It is composed of N-butyl N’-triethoxy methyl imidazolium cation and diethylhexylphosphate (D2EHPA-H as anion. The effect of the IL on the extraction efficiency was studied in presence and in absence of IL’s cation in acetate medium.

  9. Extraction of chromium(VI) by salting-out with a homogeneous, mixed solvent of water and 2-propanol: a laboratory study.

    Science.gov (United States)

    Samaratunga, Sethsiri S; Nishimoto, Jun; Tabata, Masaaki

    2008-01-01

    Chromium enters into the aquatic environment as a result of effluent discharge from steel works, electroplating, leather tanning industries and chemical industries. As the Cr(VI) is very harmful to living organisms, it should be quickly removed from the environment when it happens to be contaminated. Therefore, the aim of this laboratory research was to develop a rapid, simple and adaptable solvent extraction system to quantitatively remove Cr(VI) from polluted waters. Aqueous salt-solutions containing Cr(VI) as CrO4(2-) at ppm level (4-6 ppm) were prepared. Equal volumes (5 ml) of aqueous and organic (2-PrOH) phases were mixed in a 10 ml centrifuge tube for 15 min, centrifuged and separated. Concentrations of Cr(VI), in both the aqueous and organic phases, were determined by atomic absorption spectrometry. The effects of salt and acid concentrations, and phase-contact time on the extraction of Cr(VI) were investigated. In addition, the extraction of Cr(VI) was assessed in the presence of tetramethylammonium chloride (TMAC) in 2-PrOH phase. Effects of some other metals, (Cd(II), Co(II), Cu(II), Ni(II) and Zn(II)), on the extraction of Cr(VI) were also investigated. The Cr(VI) at ppm level was extracted quantitatively by salting-out the homogeneous system of water and 2-propanol(2-PrOH) using chloride salts, namely CaCl2 or NaCl, under acidic chloride media. The extracted chemical species of Cr(VI) was confirmed to be the CrO3Cl-. The ion-pair complex extracted into the organic phase was rationalized as the solvated ion-pair complex of [2-PrOH2+, CrO3Cl-]. The complex was no longer stable. It implied the reaction between extracted species. Studies revealed that salts and acid directly participated in the formation of the above complex. Use of extracting agents (TMAC) didn't show any significant effect on the extraction of Cr(VI) under high salting-out conditions. There is no significant interference effect on the extraction of Cr(VI) by the presence of other metals

  10. HLA class II alleles in the Otomi population of the Mezquital Valley: a genetic approach to the history of interethnic migrations in the Mexican Central Plateau.

    Science.gov (United States)

    Juárez-Martín, Ana Itzel; González-Sobrino, Blanca Zoila; Olvera, Ángel Eduardo Camarena; Falfán-Valencia, Ramcés

    2014-01-01

    From a historical and genetic point of view, the Otomi of the Mezquital Valley are a frontier people that have played an important role in the population dynamics of the Mexican Central Plateau. Due to the antiquity of their presence in the area, the Otomi may be bearers of ancient genetic variability, shared mainly today with other groups belonging to the Otomanguean linguistic family and with the Nahua. In this study we analyzed the HLA class II allele frequencies reported in Mexican indigenous populations, in order to provide an intraregional-level historical perspective of the genetic relationships between the Otomi of the Mezquital Valley and indigenous populations from other regions of Mexico. We examined genetic variation in HLA-DRB1 and -DQB1 loci in 66 nonrelated individuals belonging to seven indigenous communities from the Ixmiquilpan municipality in the Mezquital Valley, in the State of Hidalgo, Mexico. The variability of the HLA-DRB1 gene among the Otomi of the Mezquital Valley was mainly concentrated in five alleles: -DRB1*08:02 (31.06%), -DRB1*04:07 (25.77%), -DRB1*14:06 (7.55%), -DRB1*14:02 (6.06%), and -DRB1*16:02 (4.55%); these alleles have been previously described in other indigenous populations. The most frequent alleles at the HLA-DQB1 locus were -DQB1*03:02 (34.09%), -DQB1*04:02 (31.03%), and -DQB1*03:01 (19.7%). Furthermore, the HLA-DQB1*02:02 allele was found in the Otomi group with a frequency of 2.27%; this allele has not been reported in Mexican indigenous populations. In conclusion, the genetic constitution of the Otomi population is intermediate to the northern groups and the genetic variability shared by the peoples of the central regions of Mexico. Furthermore, HLA-DRB1 and -DQB1 allelic variability among the Otomi provides insight into the historical processes implied in the biological admixture with European, Asian, and African populations as well as in the admixture with the population of Mexico City associated with long

  11. Corneal hysteresis in mucopolysaccharidosis I and VI.

    Science.gov (United States)

    Fahnehjelm, Kristina Teär; Chen, Enping; Winiarski, Jacek

    2012-08-01

    High intraocular pressure (IOP) and glaucoma are often suspected in patients with mucopolysaccharidosis (MPS). To determine corneal hysteresis (CH) and IOP in children with mucopolysaccharidosis I-Hurler (MPS I-H) and MPS VI. Clinical measurements with ocular response analyzer (ORA). In seven patients, five with MPS I-H treated with stem cell transplantation (SCT), and two with MPS VI, one treated with SCT and the other with enzyme therapy, the IOP was examined with ORA. Ocular response analyzer measurements were made at a median age of 8.7 years in the patients with MPS I-H and at a median age of 9.3 years in the patients with MPS VI. Earlier measurements had raised suspicion of high IOP in one patient. The ORA showed an increased CH and a falsely high IOP values in all 14 eyes. The recalculated IOPs were normal in all 14 eyes. Mild to severe corneal opacities were present in all 14 eyes. Optic disc areas, borders and cupping were clinically normal in the 12 of 14 eyes that were possible to examine. Severe corneal opacities hampered optic disc evaluation in the older patient with MPS VI. Three eyes in two patients had normal thickness of the retinal nerve fibre layer measured with scanning laser polarimetry with corneal compensation (GDx VCC). No patient was diagnosed or treated for glaucoma. The IOPs are often falsely high because of an increased resistance of the cornea and correlate to the extent of corneal clouding. In this small, cross-sectional study, it appears that corneal resistance is directly correlated with corneal clouding, although a longitudinal study that evaluates resistance as the cornea clears with treatment would provide more direct evidence that corneal deposits are directly related to resistance. A correct measured IOP can avoid unnecessary medical or surgical hypotensive treatment. © 2011 The Authors. Acta Ophthalmologica © 2011 Acta Ophthalmologica Scandinavica Foundation.

  12. Prospek pengembangan industri perkulitan pada pelita VI

    Directory of Open Access Journals (Sweden)

    D Karyadi

    1995-06-01

    Full Text Available The leather industry is one of the strong competitive industry, as it comes from renewable natural resources. Therefore, the leather industry has good prospect to develop at the Pelita VI to be the industrial products export competitive. To develop leather industry and leather products should be given closed attention and well managed, especially concerning raw material supply, quality and leather waste treatment.

  13. Biomineralization of U(VI) phosphate promoted by microbially-mediated phytate hydrolysis in contaminated soils

    Science.gov (United States)

    Salome, Kathleen R.; Beazley, Melanie J.; Webb, Samuel M.; Sobecky, Patricia A.; Taillefert, Martial

    2017-01-01

    The bioreduction of uranium may immobilize a significant fraction of this toxic contaminant in reduced environments at circumneutral pH. In oxic and low pH environments, however, the low solubility of U(VI)-phosphate minerals also makes them good candidates for the immobilization of U(VI) in the solid phase. As inorganic phosphate is generally scarce in soils, the biomineralization of U(VI)-phosphate minerals via microbially-mediated organophosphate hydrolysis may represent the main immobilization process of uranium in these environments. In this study, contaminated sediments were incubated aerobically in two pH conditions to examine whether phytate, a naturally-occurring and abundant organophosphate in soils, could represent a potential phosphorous source to promote U(VI)-phosphate biomineralization by natural microbial communities. While phytate hydrolysis was not evident at pH 7.0, nearly complete hydrolysis was observed both with and without electron donor at pH 5.5, suggesting indigenous microorganisms express acidic phytases in these sediments. While the rate of hydrolysis of phytate generally increased in the presence of uranium, the net rate of inorganic phosphate production in solution was decreased and inositol phosphate intermediates were generated in contrast to similar incubations conducted without uranium. These findings suggest uranium stress enhanced the phytate-metabolism of the microbial community, while simultaneously inhibiting phosphatase production and/or activity by the indigenous population. Finally, phytate hydrolysis drastically decreased uranium solubility, likely due to formation of ternary sorption complexes, U(VI)-phytate precipitates, and U(VI)-phosphate minerals. Overall, the results of this study provide evidence for the ability of natural microbial communities to liberate phosphate from phytate in acidic sediments, possibly as a detoxification mechanism, and demonstrate the potential utility of phytate-promoted uranium

  14. Mucopolissacaridose tipo VI: relato de caso

    Directory of Open Access Journals (Sweden)

    Lais Orosco Bialon Santana

    2014-10-01

    Full Text Available Introdução: As mucopolissacaridoses são erros inatos do metabolismo de depósito lisossomal subclassificadas segundo a enzima deficiente. A arilsulfatase B (ARSB, responsável por degradar os glicosaminoglicanos (GAGs, que atuam no tecido conjuntivo, é deficiente na mucopolissacaridose tipo VI (MP VI. A MP VI tem clínica variável, sem anormalidades ao nascimento, evidenciando-se progressivamente ao acúmulo de GAGs. O diagnóstico se faz pela redução da atividade da ARSB ou da mutação genética. A principal causa de óbito é insuficiência cardíaca, ocorrendo na segunda ou terceira década de vida. Relato de Caso: Masculino, 4 anos, portador de MP VI, há 3 dias com febre e sinais flogísticos em sítio de acesso central, colocado para reposição enzimática, com flutuação e saída de material purulento. Ultrassom evidenciou coleção laminar e borramento de planos gordurosos. Ecocardiograma demonstra hipertensão pulmonar discreta decorrente de prolapso valvar mitral com refluxo discreto, além de endocardite da valva mitral. Optou-se por retirada cirúrgica do dispositivo e administração de vancomicina e amicacina. Durante internação, evoluiu bem, sem complicações pós operatórias. Conclusão: A MP VI têm inteligência preservada, baixa estatura e alterações osteomusculares, como no caso relatado. Não há correlação entre a gravidade clínica e a atividade residual enzimática. Dificuldade respiratória pode levar a hipóxia crônica, hipertensão pulmonar e insuficiência cardíaca congestiva. Das alterações cardíacas, encontramos valvulopatias, insuficiência cardíaca e hipertensão pulmonar, observadas no caso. O tratamento se faz com transplante de células-tronco hematopoiéticas e terapia de reposição enzimática.

  15. Steroidogenesis and phase II conjugation during the gametogenesis of thicklip grey mullet (Chelon labrosus) from a population showing intersex condition.

    Science.gov (United States)

    Sardi, Adriana E; Bizarro, Cristina; Cajaraville, Miren P; Ortiz-Zarragoitia, Maren

    2015-09-15

    Steroidogenesis, the process by which steroid hormones are synthesized, involves a vast number of enzymes and biochemical pathways that are susceptible to chemical modulation. Endocrine disrupting compounds (EDCs) are of special concern since they can alter hormone homeostasis by interfering with synthesis, transport and elimination of hormones. It is important to understand gender differences and the natural variation in steroid balance through gamete development in fish exposed to EDCs. The aim of this study was to determine mRNA levels of genes encoding for Steroidogenic Acute Regulatory (star) protein; the steroidogenic enzymes P450 11β hydroxylase (cyp11b1) and P450 aromatase (cyp19a1a); as well as the phase II conjugation enzymes sulfotransferase (sult) and UDP-glucuronosyltransferase (ugt), together with the activity of P450 aromatase and plasma levels of 17β-estradiol (E2) and 11-ketotestosterone (11-KT), at different gametogenic stages and in intersex individuals of the thicklip grey mullet Chelon labrosus. Results demonstrated that the transcription levels of star, sult and ugt and levels of E2 and 11-KT in plasma significantly changed with the interaction between gender and reproductive stage. Cyp11b1 and cyp19a1a transcription levels were significantly different between genders while the activity of P450 aromatase varied significantly between genders and reproductive stages. Results from a multivariate assessment demonstrated that measured endpoints distinguished male, female and intersex mullets at immature gametogenic stage. Intersex distinction was based on sult, ugt and cyp19a1a transcript levels and P450 aromatase activity. The present work provides data to be used in future experimental designs with C. labrosus species, and gives new clues about the molecular events that lead to intersex occurrence in mullets. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. [Hungarian Diet and Nutritional Status Survey - OTÁP2014. II. Energy and macronutrient intake of the Hungarian population].

    Science.gov (United States)

    Sarkadi Nagy, Eszter; Bakacs, Márta; Illés, Éva; Nagy, Barbara; Varga, Anita; Kis, Orsolya; Schreiberné Molnár, Erzsébet; Martos, Éva

    2017-04-01

    The aim of the study was to assess and monitor the dietary habits and nutrient intake of Hungarian adults. Three-day dietary records were used for dietary assessment, the sample was representative for the Hungarian population aged ≥18ys by gender and age. The mean proportion of energy from fat was higher (men: 38 energy%, women: 37 energy%), that from carbohydrates was lower (men: 45 energy%, women: 47 energy%) than recommended, the protein intake is adequate. Unfavorable change compared to the previous survey in 2009 was the increase of fat and saturated fatty acid energy percent in women, the decrease in fruit and vegetable consumption, which explains the decreased fiber intake. An increasing trend in added sugar energy percent in each age groups of both genders was observed compared to 2009. Interventions focusing on the promotion of fruit and vegetable consumption and decreasing of saturated fat and added sugar intake are needed. Orv. Hetil., 2017, 158(15), 587-597.

  17. Challenging the planetary boundaries II: Assessing the sustainable global population and phosphate supply, using a systems dynamics assessment model

    Energy Technology Data Exchange (ETDEWEB)

    Sverdrup, Harald U., E-mail: harald.sverdrup@chemeng.lth.se [Applied Systems Analysis and Dynamics Group, Chemical Engineering, Lund University, Box 124, SE-221 00 Lund (Sweden); Ragnarsdottir, Kristin Vala [Institute of Earth Sciences, School of Engineering and Natural Sciences, University of Iceland, IS-101 Reykjavik (Iceland)

    2011-06-15

    Highlights: > Peak phosphorus supply behaviour. > Recycling essential for phosphorus supply. > Phosphorus supply is connected to food security. - Abstract: A systems dynamics model was developed to assess the planetary boundary for P supply in relation to use by human society. It is concluded that present day use rates and poor recycling rates of P are unsustainable at timescales beyond 100+ a. The predictions made suggest that P will become a scarce and expensive material in the future. The study shows clearly that market mechanisms alone will not be able to secure an efficient use before a large part of the resource will have been allowed to dissipate into the natural environment. It is suggested that population size management and effective recycling measures must be planned long term to avoid unpleasant consequences of hunger and necessary corrections imposed on society by mass balance and thermodynamics.

  18. OSSOS. II. A SHARP TRANSITION IN THE ABSOLUTE MAGNITUDE DISTRIBUTION OF THE KUIPER BELT’S SCATTERING POPULATION

    Energy Technology Data Exchange (ETDEWEB)

    Shankman, C. [Department of Physics and Astronomy, University of Victoria, Elliott Building, 3800 Finnerty Road, Victoria, British Columbia V8P 5C2 (Canada); Kavelaars, JJ.; Bannister, M. T.; Gwyn, S. [National Research Council of Canada, Victoria, BC (Canada); Gladman, B. J.; Alexandersen, M. [Department of Physics and Astronomy, The University of British Columbia, Vancouver, BC (Canada); Kaib, N. [Department of Terrestrial Magnetism, Carnegie Institution for Science, Washington, DC (United States); Petit, J.-M. [Institut UTINAM, CNRS-Université de Franche-Comté, Besançon (France); Chen, Y.-T. [Institute for Astronomy and Astrophysics, Academia Sinica, Taiwan (China); Jakubik, M. [Astronomical Institute of the Slovak Academy of Sciences, Tatranská Lomnica, The Slovak Republic (Slovakia); Volk, K., E-mail: cshankm@uvic.ca [University of Arizona, Tucson, AZ (United States)

    2016-02-15

    We measure the absolute magnitude, H, distribution, dN(H) ∝ 10{sup αH}, of the scattering Trans-Neptunian Objects (TNOs) as a proxy for their size-frequency distribution. We show that the H-distribution of the scattering TNOs is not consistent with a single-slope distribution, but must transition around H{sub g} ∼ 9 to either a knee with a shallow slope or to a divot, which is a differential drop followed by second exponential distribution. Our analysis is based on a sample of 22 scattering TNOs drawn from three different TNO surveys—the Canada–France Ecliptic Plane Survey, Alexandersen et al., and the Outer Solar System Origins Survey, all of which provide well-characterized detection thresholds—combined with a cosmogonic model for the formation of the scattering TNO population. Our measured absolute magnitude distribution result is independent of the choice of cosmogonic model. Based on our analysis, we estimate that the number of scattering TNOs is (2.4–8.3) × 10{sup 5} for H{sub r} < 12. A divot H-distribution is seen in a variety of formation scenarios and may explain several puzzles in Kuiper Belt science. We find that a divot H-distribution simultaneously explains the observed scattering TNO, Neptune Trojan, Plutino, and Centaur H-distributions while simultaneously predicting a large enough scattering TNO population to act as the sole supply of the Jupiter-Family Comets.

  19. Nitrification inhibition by hexavalent chromium Cr(VI)--Microbial ecology, gene expression and off-gas emissions.

    Science.gov (United States)

    Kim, Young Mo; Park, Hongkeun; Chandran, Kartik

    2016-04-01

    The goal of this study was to investigate the responses in the physiology, microbial ecology and gene expression of nitrifying bacteria to imposition of and recovery from Cr(VI) loading in a lab-scale nitrification bioreactor. Exposure to Cr(VI) in the reactor strongly inhibited nitrification performance resulting in a parallel decrease in nitrate production and ammonia consumption. Cr(VI) exposure also led to an overall decrease in total bacterial concentrations in the reactor. However, the fraction of ammonia oxidizing bacteria (AOB) decreased to a greater extent than the fraction of nitrite oxidizing bacteria (NOB). In terms of functional gene expression, a rapid decrease in the transcript concentrations of amoA gene coding for ammonia oxidation in AOB was observed in response to the Cr(VI) shock. In contrast, transcript concentrations of the nxrA gene coding for nitrite oxidation in NOB were relatively unchanged compared to Cr(VI) pre-exposure levels. Therefore, Cr(VI) exposure selectively and directly inhibited activity of AOB, which indirectly resulted in substrate (nitrite) limitation to NOB. Significantly, trends in amoA expression preceded performance trends both during imposition of and recovery from inhibition. During recovery from the Cr(VI) shock, the high ammonia concentrations in the bioreactor resulted in an irreversible shift towards AOB populations, which are expected to be more competitive in high ammonia environments. An inadvertent impact during recovery was increased emission of nitrous oxide (N2O) and nitric oxide (NO), consistent with recent findings linking AOB activity and the production of these gases. Therefore, Cr(VI) exposure elicited multiple responses on the microbial ecology, gene expression and both aqueous and gaseous nitrogenous conversion in a nitrification process. A complementary interrogation of these multiple responses facilitated an understanding of both direct and indirect inhibitory impacts on nitrification. Copyright

  20. Can iron oxides remove Cr(VI) from drinking water at sub-ppb levels?

    Science.gov (United States)

    Kaprara, Efthymia; Simeonidis, Konstantinos; Samaras, Petros; Zouboulis, Anastasios; Mitrakas, Manassis

    2013-04-01

    Hexavalent chromium [Cr(VI)] has long been recognized as a potential carcinogen via inhalation, in contrast to trivalent chromium [Cr(III)] which is 100 times less toxic and also a necessary nutrient, essential to human glucidic metabolism. Nowadays there is an increasing concern that Cr(VI) is also carcinogenic by the oral route of exposure, while an increased number of publications indicate that Cr(VI) is a common natural pollutant. Hexavalent chromium formation is attributed to natural oxidation of Cr(III) in ultramafic derived soils and ophiolithic rocks. To verify this theory, drinking water samples were collected from targeted areas of Greece e.g. areas in which the geological background is predominated by ultramafic minerals and the water supply depends mainly on groundwater resources. Valuable guide for the samples collection was the geological map of Greece and emphasis was given to regions where the natural occurrence of Cr(VI) is thought to be more possible. A wide range of Cr concentrations (2-100 μg/L) were detected in the areas studied, with most of them ranging below the current limit of 50 μg/L, and the Cr(VI) concentration being more than 90% of the total. Since the Cr(VI) affects significant part of population worldwide, a debate was established concerning the enforcement of stringent regulation, which also demands the drinking water treatment processes re-evaluation in view of Cr(VI) removal at sub-ppb level. In this regard, adsorption has evolved as the front line of defense for chromium removal. The motivation of this work was to investigate the efficiency of iron oxides for the adsorption of Cr(VI) from drinking water and its removal at sub-ppb levels. The adsorbents examined included iron oxy-hydroxides and magnetite prepared using common low cost iron salts. Their effectiveness as Cr(VI) adsorbents was evaluated through the decrease of a Cr(VI) concentration of 100μg/L prepared in NSF water at pH 7. Preliminary batch experiments did not

  1. Star formation history of Canis Major OB1. II. A bimodal X-ray population revealed by XMM-Newton

    Science.gov (United States)

    Santos-Silva, T.; Gregorio-Hetem, J.; Montmerle, T.; Fernandes, B.; Stelzer, B.

    2018-02-01

    Aims: The Canis Major OB1 Association has an intriguing scenario of star formation, especially in the region called Canis Major R1 (CMa R1) traditionally assigned to a reflection nebula, but in reality an ionized region. This work is focussed on the young stellar population associated with CMa R1, for which our previous results from ROSAT, optical, and near-infrared data had revealed two stellar groups with different ages, suggesting a possible mixing of populations originated from distinct star formation episodes. Methods: The X-ray data allow the detected sources to be characterized according to hardness ratios, light curves, and spectra. Estimates of mass and age were obtained from the 2MASS catalogue and used to define a complete subsample of stellar counterparts for statistical purposes. Results: A catalogue of 387 XMM-Newton sources is provided, of which 78% are confirmed as members or probable members of the CMa R1 association. Flares (or similar events) were observed for 13 sources and the spectra of 21 bright sources could be fitted by a thermal plasma model. Mean values of fits parameters were used to estimate X-ray luminosities. We found a minimum value of log(LX [erg/s] ) = 29.43, indicating that our sample of low-mass stars (M⋆ ≤ 0.5 M⊙), which are faint X-ray emitters, is incomplete. Among the 250 objects selected as our complete subsample (defining our "best sample"), 171 are found to the east of the cloud, near Z CMa and dense molecular gas, of which 50% of them are young (10 Myr). The opposite happens to the west, near GU CMa, in areas lacking molecular gas: among 79 objects, 30% are young and 50% are older. These findings confirm that a first episode of distributed star formation occurred in the whole studied region 10 Myr ago and dispersed the molecular gas, while a second, localized episode (<5 Myr) took place in the regions where molecular gas is still present.

  2. Amending Subsoil with Composted Poultry Litter-II: Effects on Kentucky Bluegrass (Poa pratensis Establishment, Root Growth, and Weed Populations

    Directory of Open Access Journals (Sweden)

    Mili Mandal

    2013-10-01

    Full Text Available Turfgrasses established on a soil deprived of the topsoil during construction disturbance often have low levels of density and uniformity making them susceptible to weeds. Field experiments evaluated composted poultry litter incorporation into subsoil on Kentucky bluegrass growth attributes and subsequent effects on weed populations. Top 20 cm of topsoil was removed and composted poultry litter was incorporated at 0.1, or 0.2, or 0.4 cm/cm-soil into the exposed subsoil to a depth of 12.7 cm before seeding or sodding, and was compared to N-fertilized (50 × 10−4 kg m−2 and control plots. A greenhouse experiment was also conducted to determine the effect of compost incorporation rates on turfgrass rooting depth. Turfgrass yield from seeded plots with compost incorporation rates of 0.1, 0.2, and 0.4 cm/cm-soil, were 200%, 300%, and 500% more, respectively, compared to control plots. Composted poultry litter incorporated at 0.1 cm/cm-soil resulted in at least 70 seedlings in 7.6 cm−2, which was sufficient to attain 100% turf cover. Higher incorporation rates in seeded plots maintained lower numbers of buckhorn plantain and red clover than untreated plots. Rooting depth also increased linearly with compost rates. Overall, compost treatments were able to maintain superior turf cover and quality compared to conventionally fertilized or control plots.

  3. Physical properties of simulated galaxy populations at z = 2 - II. Effects of cosmology, reionization and ISM physics

    Science.gov (United States)

    Haas, Marcel R.; Schaye, Joop; Booth, C. M.; Dalla Vecchia, Claudio; Springel, Volker; Theuns, Tom; Wiersma, Robert P. C.

    2013-11-01

    We use hydrodynamical simulations from the OverWhelmingly Large Simulations project to investigate the dependence of the physical properties of galaxy populations at redshift 2 on the assumed star formation law, the equation of state imposed on the unresolved interstellar medium, the stellar initial mass function, the reionization history and the assumed cosmology. This work complements that of Paper I, where we studied the effects of varying models for galactic winds driven by star formation and active galactic nucleus. The normalization of the matter power spectrum strongly affects the galaxy mass function, but has a relatively small effect on the physical properties of galaxies residing in haloes of a fixed mass. Reionization suppresses the stellar masses and gas fractions of low-mass galaxies, but by z = 2 the results are insensitive to the timing of reionization. The stellar initial mass function mainly determines the physical properties of galaxies through its effect on the efficiency of the feedback, while changes in the recycled mass and metal fractions play a smaller role. If we use a recipe for star formation that reproduces the observed star formation law independently of the assumed equation of state of the unresolved interstellar medium, then the latter is unimportant. The star formation law, i.e. the gas consumption time-scale as a function of surface density, determines the mass of dense, star-forming gas in galaxies, but affects neither the star formation rate nor the stellar mass. This can be understood in terms of self-regulation: the gas fraction adjusts until the outflow rate balances the inflow rate.

  4. A Submillimeter Perspective on the Goods Fields. II. The High Radio Power Population in the Goods-N

    Science.gov (United States)

    Barger, A. J.; Cowie, L. L.; Owen, F. N.; Hsu, L.-Y.; Wang, W.-H.

    2017-01-01

    We use ultradeep 20 cm data from the Karl G. Jansky Very Large Array and 850 μm data from SCUBA-2 and the Submillimeter Array of an 124 arcmin2 region of the Chandra Deep Field-north to analyze the high radio power ({P}20{cm}> {10}31 erg s-1 Hz-1) population. We find that 20 (42 ± 9%) of the spectroscopically identified z> 0.8 sources have consistent star formation rates (SFRs) inferred from both submillimeter and radio observations, while the remaining sources have lower (mostly undetected) submillimeter fluxes, suggesting that active galactic nucleus (AGN) activity dominates the radio power in these sources. We develop a classification scheme based on the ratio of submillimeter flux to radio power versus radio power and find that it agrees with AGN and star-forming galaxy classifications from Very Long Baseline Interferometry. Our results provide support for an extremely rapid drop in the number of high SFR galaxies above about a thousand solar masses per year (Kroupa initial mass function) and for the locally determined relation between X-ray luminosity and radio power for star-forming galaxies applying at high redshifts and high radio powers. We measure far-infrared (FIR) luminosities and find that some AGNs lie on the FIR-radio correlation, while others scatter below. The AGNs that lie on the correlation appear to do so based on their emission from the AGN torus. We measure a median radio size of 1.″0 ± 0.3 for the star-forming galaxies. The radio sizes of the star-forming galaxies are generally larger than those of the AGNs. The W. M. Keck Observatory is operated as a scientific partnership among the California Institute of Technology, the University of California, and NASA, and was made possible by the generous financial support of the W. M. Keck Foundation.

  5. The BaLROG project - II. Quantifying the influence of bars on the stellar populations of nearby galaxies

    Science.gov (United States)

    Seidel, M. K.; Falcón-Barroso, J.; Martínez-Valpuesta, I.; Sánchez-Blázquez, P.; Pérez, I.; Peletier, R.; Vazdekis, A.

    2016-08-01

    We continue the exploration of the BaLROG (Bars in Low Redshift Optical Galaxies) sample: 16 large mosaics of barred galaxies observed with the integral field unit Spectrographic Areal Unit for Research on Optical Nebulae. We quantify the influence of bars on the composition of the stellar component. We derive line-strength indices of H β, Fe5015 and Mgb. Based on single stellar population (SSP) models, we calculate ages, metallicities and [Mg/Fe] abundances and their gradients along the bar major and minor axes. The high spatial resolution of our data allows us to identify breaks among index and SSP profiles, commonly at 0.13 ± 0.06 bar length, consistent with kinematic features. Inner gradients are about 10 times steeper than outer gradients and become larger when there is a central rotating component, implying that the gradients are not independent of dynamics and orbits. Central ages appear to be younger for stronger bars. Yet, the bar regions are usually old. We find a flattening of the iron (Fe5015) and magnesium (Mgb) outer gradients along the bar major axis, translating into a flattening of the metallicity gradient. This gradient is found to be 0.03 ± 0.07 dex kpc-1 along the bar major axis while the mean value of the bar minor axis compares well with that of an unbarred control sample and is significantly steeper, namely -0.20 ± 0.04 dex kpc-1. These results confirm recent simulations and discern the important localized influence of bars. The elevated [Mg/Fe] abundances of bars and bulges compared to the lower values of discs suggest an early formation, in particular for early-type galaxies.

  6. Farvel til globaliseringen som vi kendte den

    DEFF Research Database (Denmark)

    Böss, Michael

    2009-01-01

    Vi er endt med en krise, som rækker langt ud over det globale monetære system, fordi den ideologiske ortodoksi, der skabte den, har ført til udflytning af millioner af arbejdspladser, tæring af nationalstaternes sammenhængskraft og overgreb på naturen. Kronikken refererer bl.a. til John Maynard...... Keynes og en artikel af økonomen Robert Skidelsky i The American Prospect. Udgivelsesdato: 12. januar 2009...

  7. "LICENS ER NOGET VI GIVER TIL HINANDEN"

    OpenAIRE

    Svendsen, Nana Lysbo; Birksholm, Sarah Schlander; Rosendahl, Rasmus; Albrechtsen, Nadja Loran

    2013-01-01

    This study consists of a rhetorical analysis of how the Danish Broadcasting Corporation argues for the compulsory license fee in their campaign video: ’Licens er noget vi giver til hinanden’. On the assumption that a visual product can argue on equal terms with the spoken language, the paper will look at the specific visual tools that are used in the argumentation and the portrayal of the concept of public service and the license fee. In extension to this the paper will examine if the vid...

  8. Genetic drift vs. natural selection in a long-term small isolated population: major histocompatibility complex class II variation in the Gulf of California endemic porpoise (Phocoena sinus).

    Science.gov (United States)

    Munguia-Vega, Adrian; Esquer-Garrigos, Yareli; Rojas-Bracho, Lorenzo; Vazquez-Juarez, Ricardo; Castro-Prieto, Aines; Flores-Ramirez, Sergio

    2007-10-01

    Although many studies confirm long-term small isolated populations (e.g. island endemics) commonly sustain low neutral genetic variation as a result of genetic drift, it is less clear how selection on adaptive or detrimental genes interplay with random forces. We investigated sequence variation at two major histocompatibility complex (Mhc) class II loci on a porpoise endemic to the upper Gulf of California, México (Phocoena sinus, or vaquita). Its unique declining population is estimated around 500 individuals. Single-strand conformation polymorphism analysis revealed one putative functional allele fixed at the locus DQB (n = 25). At the DRB locus, we found two presumed functional alleles (n = 29), differing by a single nonsynonymous nucleotide substitution that could increase the stability at the dimer interface of alphabeta-heterodimers on heterozygous individuals. Identical trans-specific DQB1 and DRB1 alleles were identified between P. sinus and its closest relative, the Burmeister's porpoise (Phocoena spinipinnis). Comparison with studies on four island endemic mammals suggests fixation of one allele, due to genetic drift, commonly occurs at the DQA or DQB loci (effectively neutral). Similarly, deleterious alleles of small effect are also effectively neutral and can become fixed; a high frequency of anatomical malformations on vaquita gave empirical support to this prediction. In contrast, retention of low but functional polymorphism at the DRB locus was consistent with higher selection intensity. These observations indicated natural selection could maintain (and likely also purge) some crucial alleles even in the face of strong and prolonged genetic drift and inbreeding, suggesting long-term small populations should display low inbreeding depression. Low levels of Mhc variation warn about a high susceptibility to novel pathogens and diseases in vaquita.

  9. Oral–Facial–Digital Syndrome type VI with self mutilations

    Directory of Open Access Journals (Sweden)

    Rabah M. Shawky

    2014-10-01

    Full Text Available We report the case of a 2.5 year old female, 2nd in order of birth of 1st cousin consanguineous marriage, with the typical features of Oral–Facial–Digital Syndrome type VI (OFDS VI including midline pseudo cleft upper lip, sublingual nodule, molar tooth sign by MRI brain, bilateral mesoaxial polydactyly (hexadactyly, and developmental delay. The patient had self mutilations which was not reported before in OFDS VI except once.

  10. Discovery of oxygen in the PG 1159 degenerate stars - A direct evolutionary link to O VI planetary nebula nuclei and confirmation of pulsation theory

    Science.gov (United States)

    Sion, E. M.; Liebert, J.; Starrfield, S. G.

    1985-01-01

    The discovery of strong O VI absorption/emission lines in five members of the PG 1159 degenerate stars is reported. It is shown that the optical spectra are dominated by C IV, O VI, and He II, with no detectable N lines. It is confirmed that the planetary nebula-central star, K1-16, which is found to be a pulsating star by Grauer and Bond (1984), is a member of the spectroscopic group. The detection of strong oxygen features in the photospheres of the objects provides support of the prediction of Starrfield et al. (1984). The properties of the PG 1159 stars are compared with the so-called O VI central stars of planetary nebulae and both groups of stars are found to have similar spectral features, temperatures, and luminosities. The implications of the O VI/PG 1159 evolutionary link are assessed.

  11. Environmental survey of Region VI, Haltenbanken, 2009; Miljoeundersoekelse i Region VI, Haltenbanken, 2009

    Energy Technology Data Exchange (ETDEWEB)

    Holm, May-Helen; Cochrane, Sabine; Mannvik, Hans-Petter; Wasbotten, Ingar Halvorsen

    2010-07-01

    There has been an environmental investigation in Region VI Halten Bank. This report presents the results of the chemical and biological assays performed on samples from a total of 316 stations in 16 fields and 15 regional stations. A status of environmental conditions in the region is given at the end of the report. (AG)

  12. Environmental Survey in Region VI, Haltenbanken, 2009. Summary report; Miljoeundersoekelse i Region VI, Haltenbanken, 2009. Sammendragsrapport

    Energy Technology Data Exchange (ETDEWEB)

    Mannvik, Hans-Petter; Wasbotten, Ingar Halvorsen

    2010-07-01

    An environmental survey of Region VI, Haltenbanken, has been carried out. This report presents the results from the analyses carried out on samples from a total of 316 stations at 16 fields and 15 regional stations. A status of the environmental conditions in the region is given at the end of the report. (Author)

  13. Fremtidens lavenergibyggeri - kan vi gøre som vi plejer?

    DEFF Research Database (Denmark)

    Larsen, Tine Steen

    2011-01-01

    Stramninger af kravene til energiforbruget i vores boliger medfører stor fokus på energiberegningen, men erfaringer fra lavenergiboliger opført i dag viser, at vi, for at sikre succes for fremtidens boliger, også skal inddrage dokumentation af indeklimaet og forbedre samarbejdet mellem arkitekter...

  14. Removal of cadmium (II), lead (II) and chromium (VI) in water with nanomaterials

    OpenAIRE

    Contreras Rodríguez, Ada Rebeca

    2015-01-01

    Resumen Un gran desafío para este siglo es el saneamiento de los residuos generados durante las actividades industriales, domésticas y agrícolas. El agua, como parte vital del ciclo de vida, está fuertemente afectada por estas actividades y finalmente se puede volver inutilizable. Entre los numerosos contaminantes que se encuentran en el agua, los metales pesados requieren atención especial ya que no son biodegradables y con frecuencia se acumulan en el medio ambiente causando efectos negativ...

  15. Vi lider af prætraumatisk stress

    DEFF Research Database (Denmark)

    Hansen, Brian Benjamin

    2009-01-01

    Vi lider af prætraumatisk stress. Vi vil nemlig nå det hele og presser konstant nye aftaler ind i vores kalender. Det eneste, der hjælper, er at ’gøre intet’ – men kan man overhovedet det? Udgivelsesdato: 30.09.09......Vi lider af prætraumatisk stress. Vi vil nemlig nå det hele og presser konstant nye aftaler ind i vores kalender. Det eneste, der hjælper, er at ’gøre intet’ – men kan man overhovedet det? Udgivelsesdato: 30.09.09...

  16. Behaviour of chromium(VI) in stormwater soil infiltration systems

    DEFF Research Database (Denmark)

    Cederkvist, Karin; Ingvertsen, Simon T.; Jensen, Marina B.

    2013-01-01

    The ability of stormwater infiltration systems to retain Cr(VI) was tested by applying a synthetic stormwater runoff solution with a neutral pH and high Cr(VI) concentrations to four intact soil columns excavated from two roadside infiltration swales in Germany. Inlet flow rates mimicked normal (10......, while under extreme rain events approximately 20% of Cr(VI) was retained. In both cases effluent concentrations of Cr(VI) would exceed the threshold value of 3.4 mu g/L if the infiltrated water were introduced to freshwater environments. More knowledge on the composition of the stormwater runoff...

  17. Remediation of Cr(VI) in solution using vitamin C*

    OpenAIRE

    LIU, Yong; Xu, Xin-hua; He, Ping

    2005-01-01

    The effectiveness of vitamin C in treating Cr(VI)-contaminated water is being evaluated. Cr(VI) is an identified pollutant of some soils and groundwater. Vitamin C, an important biological reductant in humans and animals, can be used to transform Cr(VI) to essentially nontoxic Cr(III). The removal efficiency was 89% when the mass concentration of vitamin C was 80 mg/L in 60 min, and nearly 100% Cr(VI) was removed when the mass concentration was 100 mg/L. Our data demonstrated that the removal...

  18. Heterogeneity of collagens in rabbit cornea: type VI collagen

    National Research Council Canada - National Science Library

    Cintron, C; Hong, BS

    1988-01-01

    .... These physical characteristics, together with the susceptibility of these polypeptides to collagenase and their amino acid composition, identified the high molecular weight aggregate as type VI collagen...

  19. Safety, immunogenicity and dose ranging of a new Vi-CRM₁₉₇ conjugate vaccine against typhoid fever: randomized clinical testing in healthy adults.

    Science.gov (United States)

    van Damme, Pierre; Kafeja, Froukje; Anemona, Alessandra; Basile, Venere; Hilbert, Anne Katrin; De Coster, Ilse; Rondini, Simona; Micoli, Francesca; Qasim Khan, Rana M; Marchetti, Elisa; Di Cioccio, Vito; Saul, Allan; Martin, Laura B; Podda, Audino

    2011-01-01

    Typhoid fever causes more than 21 million cases of disease and 200,000 deaths yearly worldwide, with more than 90% of the disease burden being reported from Asia. Epidemiological data show high disease incidence in young children and suggest that immunization programs should target children below two years of age: this is not possible with available vaccines. The Novartis Vaccines Institute for Global Health developed a conjugate vaccine (Vi-CRM₁₉₇) for infant vaccination concomitantly with EPI vaccines, either starting at 6 weeks with DTP or at 9 months with measles vaccine. We report the results from a Phase 1 and a Phase 2 dose ranging trial with Vi-CRM₁₉₇ in European adults. Following randomized blinded comparison of single vaccination with either Vi-CRM₁₉₇ or licensed polysaccharide vaccines (both containing 25·0 µg of Vi antigen), a randomised observer blinded dose ranging trial was performed in the same center to compare three concentrations of Vi-CRM₁₉₇ (1·25 µg, 5·0 µg and 12·5 µg of Vi antigen) with the polysaccharide vaccine. All vaccines were well tolerated. Compared to the polysaccharide vaccine, Vi-CRM₁₉₇ induced a higher incidence of mild to moderate short lasting local pain. All Vi-CRM₁₉₇ formulations induced higher Vi antibody levels compared to licensed control, with clear dose response relationship. Vi-CRM₁₉₇ did not elicit safety concerns, was highly immunogenic and is therefore suitable for further clinical testing in endemic populations of South Asia. ClinicalTrials.gov NCT01123941 NCT01193907.

  20. Safety, immunogenicity and dose ranging of a new Vi-CRM₁₉₇ conjugate vaccine against typhoid fever: randomized clinical testing in healthy adults.

    Directory of Open Access Journals (Sweden)

    Pierre van Damme

    Full Text Available Typhoid fever causes more than 21 million cases of disease and 200,000 deaths yearly worldwide, with more than 90% of the disease burden being reported from Asia. Epidemiological data show high disease incidence in young children and suggest that immunization programs should target children below two years of age: this is not possible with available vaccines. The Novartis Vaccines Institute for Global Health developed a conjugate vaccine (Vi-CRM₁₉₇ for infant vaccination concomitantly with EPI vaccines, either starting at 6 weeks with DTP or at 9 months with measles vaccine. We report the results from a Phase 1 and a Phase 2 dose ranging trial with Vi-CRM₁₉₇ in European adults.Following randomized blinded comparison of single vaccination with either Vi-CRM₁₉₇ or licensed polysaccharide vaccines (both containing 25·0 µg of Vi antigen, a randomised observer blinded dose ranging trial was performed in the same center to compare three concentrations of Vi-CRM₁₉₇ (1·25 µg, 5·0 µg and 12·5 µg of Vi antigen with the polysaccharide vaccine.All vaccines were well tolerated. Compared to the polysaccharide vaccine, Vi-CRM₁₉₇ induced a higher incidence of mild to moderate short lasting local pain. All Vi-CRM₁₉₇ formulations induced higher Vi antibody levels compared to licensed control, with clear dose response relationship.Vi-CRM₁₉₇ did not elicit safety concerns, was highly immunogenic and is therefore suitable for further clinical testing in endemic populations of South Asia.ClinicalTrials.gov NCT01123941 NCT01193907.

  1. Late Neanderthals at Jarama VI (central Iberia)?

    Science.gov (United States)

    Kehl, Martin; Burow, Christoph; Hilgers, Alexandra; Navazo, Marta; Pastoors, Andreas; Weniger, Gerd-Christian; Wood, Rachel; Jordá Pardo, Jesús F.

    2013-09-01

    Previous geochronological and archaeological studies on the rock shelter Jarama VI suggested a late survival of Neanderthals in central Iberia and the presence of lithic assemblages of Early Upper Paleolithic affinity. New data on granulometry, mineralogical composition, geochemical fingerprints and micromorphology of the sequence corroborate the previous notion that the archaeological units JVI.2.1 to JVI.2.3 are slackwater deposits of superfloods, which did not experience significant post-depositional changes, whereas the artifact-rich units JVI.3 and JVI.1 mainly received sediment inputs by sheetwash and cave spall. New AMS radiocarbon measurements on three samples of cut-marked bone using the ultrafiltration technique yielded ages close to, or beyond, the limit of radiocarbon dating at ca. 50 14C ka BP, and hence suggest much higher antiquity than assumed previously. Furthermore, elevated temperature post-IR IRSL luminescence measurements on K feldspars yielded burial ages for subunits JVI.2.2 and JVI.2.3 between 50 and 60 ka. Finally, our reappraisal of the stone industry strongly suggests that the whole sequence is of Mousterian affinity. In conclusion, Jarama VI most probably does not document a late survival of Neanderthals nor an Early Upper Paleolithic occupation in central Iberia, but rather indicates an occupation breakdown after the Middle Paleolithic.

  2. Investigation of uranium (VI) adsorption by polypyrrole.

    Science.gov (United States)

    Abdi, S; Nasiri, M; Mesbahi, A; Khani, M H

    2017-06-15

    The purpose of this study was to investigate the adsorption of uranium (VI) ions on the polypyrrole adsorbent. Polypyrrole was synthesized by a chemical method using polyethylene glycol, sodium dodecylbenzenesulfonate, and cetyltrimethylammonium bromide as the surfactant and iron (III) chloride as an oxidant in the aqueous solution. The effect of various surfactants on the synthesized polymers and their performance as the uranium adsorbent were investigated. Adsorbent properties were characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) techniques. The effect of different parameters such as pH, contact time, initial metal ion concentrations, adsorbent dose, and the temperature was investigated in the batch system for uranium adsorption process. It has been illustrated that the adsorption equilibrium time is 7min. The results showed that the Freundlich model had the best agreement and the maximum adsorption capacity of polypyrrole for uranium (VI) was determined 87.72mg/g from Langmuir isotherm. In addition, the mentioned adsorption process was fast and the kinetic data were fitted to the Pseudo first and second order models. The adsorption kinetic data followed the pseudo-second-order kinetic model. Moreover, the thermodynamic parameters ΔG(0), ΔH(0) and ΔS(0) showed that the uranium adsorption process by polypyrrole was endothermic and spontaneous. Copyright © 2017. Published by Elsevier B.V.

  3. Interaction of monosaccharides and related compounds with oxocations of Mo(VI), W(VI) and U(VI) studied by NMR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Geraldes, C.F.G.C.; Castro, M.M.C.A.; Saraiva, M.E.; Aureliano, M.; Dias, B.A.

    1988-05-01

    Proton, /sup 13/C and /sup 31/P nuclear magnetic resonance spectroscopy has been used to study the complexation of Mo(VI), W(VI) and U(VI) oxocations with various aldoses, cyclic polyols and ribose-5-phosphate in aqueous solution. The aldoses D-mannose, D-lyxose and D-ribose form tridentate complexes with Mo(VI) and W(VI) at pH similarly ordered 5, via the 1,2,3-hydroxyl groups, which are cis to each other in these sugars. Other aldoses, like D-arabinose, D-glucose, D-xylose and D-galactose form weaker bidentate complexes with those ions because they can only use the 1 and 3-cis hydroxyl groups in metal binding. These bidentate interactions also take place in the binding of U(VI) to D-mannose and D-ribose, at pH similarly ordered 10. However, sugars having 1,3,5-hydroxyl groups in the cis position do not form stable chelates with these oxocations, possibly due to steric crowding. In the case of ribose-5-phosphate, the phosphate group is the exclusive binding site for the three oxocations, except for U(VI) at very basic pH (pH > 10), where the hydroxyl groups also interact with UO/sub 2//sup 2 +/.

  4. Tolerance and Reduction of Chromium(VI by Bacillus sp. MNU16 Isolated from Contaminated Coal Mining Soil

    Directory of Open Access Journals (Sweden)

    Neha Upadhyay

    2017-05-01

    Full Text Available The bacterium MNU16 was isolated from contaminated soils of coal mine and subsequently screened for different plant growth promoting (PGP activities. The isolate was further identified by 16S rRNA sequencing as Bacillus subtilis MNU16 with IAA concentration (56.95 ± 0.43 6μg/ml, siderophore unit (9.73 ± 2.05%, phosphate solubilization (285.13 ± 1.05 μg/ml and ACC deaminase activity (116.79 ± 0.019 μmoles α-ketobutyrate/mg/24 h. Further, to evaluate the metal resistance profile of bacterium, the isolate was screened for multi-metal resistance (viz. 900 mg/L for Cr, 600 mg/L for As, 700 mg/L for Ni and 300 mg/L for Hg. Additionally, the resistance pattern of B. subtilis MNU16 against Cr(VI (from 50 to 300 mg/L treatments were evaluated. An enriched population was observed at 0–200 mg/L Cr(VI concentration while slight reductions were observed at 250 and 300 mg/L Cr(VI. Further, the chromium reduction ability at 50 mg/L of Cr(VI highlighted that the bacterium B. subtilis MNU16 reduced 75% of Cr(VI to 13.23 mg/L within 72 h. The localization of electron dense precipitates was observed in the TEM images of B. subtilis MNU16 which is might be due to the reduction of Cr(VI to Cr(III. The data of fluorescence microscopy and flow cytometry with respect to Cr(VI treatments (50–300 mg/L showed a similar pattern and clearly revealed the less toxic effect of hexavalent chromium upto 200 mg/L Cr(VI concentration. However, toxicity effects were more pronounced at 300 mg/L Cr(VI. Therefore, the present study suggests that the plant growth promoting potential and resistance efficacy of B. subtilis MNU16 will go a long way in developing an effective bioremediation approach for Cr(VI contaminated soils.

  5. A fuzzy set approach to economic crisis, austerity and public health. Part II: How are configurations of crisis and austerity related to changes in population health across Europe?

    Science.gov (United States)

    Saltkjel, Therese; Holm Ingelsrud, Mari; Dahl, Espen; Halvorsen, Knut

    2017-08-01

    Based on the ideal type classification of European countries done in Part I of this paper, Part II explores whether the real 'danger' to public health is the interplay between austerity and crisis, rather than recession itself. We constructed two fuzzy sets of changes in population health based on a pooled file of European Union Statistics on Income and Living Conditions (EU-SILC) data (2008 and 2013) including 29 European countries. The linear probability analyses of 'limiting long-standing illness' and 'less than good' health were restricted to the age group 20-64 years. We performed fuzzy set qualitative comparative analysis (fsQCA) and studied whether configurations of 'severe crisis' and 'austerity' were linked to changes in population health. Overall, the results of this fsQCA do not support the 'crisis-austerity' thesis. Results on 'less than good' health were highly inconsistent, while results on 'limiting long-standing illness', contrary to the thesis, showed a two-path model. Countries with either no severe crisis or no austerity were subsets of the set of countries that experienced deteriorated health. Results also show that several countries combined both paths. This fuzzy set analysis does not support Stuckler and Basu's 'crisis-austerity' thesis, as those European countries that experienced recession and austerity were not consistently the countries with deteriorating health. There may be multiple reasons for this result, including analytical approach and operationalization of key concepts, but also resilient forces such as family support. We suggest more research on the topic based on more recent data and possibly other, or more, dimensions of austerity.

  6. Population distance between Dakshina Kannada (South India) and Gujarati (North India) population using infracranial nonmetric traits.

    Science.gov (United States)

    Nayak, S R; Kumar, Madhan; Krishnamurthy, A; Prabhu, Latha V; D'Costa, Sujatha; Ramanathan, Lakshmi A; Potu, Bhagath K; Gorantla, Vasavi R

    2007-01-01

    Infracranial nonmetric variations have been considered for determining population distance between different regions and continents, in recent times. We studied different infracranial nonmetric traits from the Dakshina Kannada (South India) region to compare with the data available from the Gujarati (North India) region. The mean measure of divergence between the two different geographic regions showed significant variation. In our study, the incidence like i) Allen's fossa of the femur, ii) plaque formation in the upper end of the femur, iii) exostosis in trochanteric fosse of femur, iv) third trochanter of femur, v) os trigonum of talus, vi) medial talar facet, vii) peroneal tubercle of calcaneus, viii) bipartite transverse foramen in the cervical vertebra, too showed significant side difference.

  7. Depression, Somatization, and Posttraumatic Stress Disorder in Children Born of Occupation After World War II in Comparison With a General Population.

    Science.gov (United States)

    Kaiser, Marie; Kuwert, Philipp; Braehler, Elmar; Glaesmer, Heide

    2015-10-01

    At the end of World War II and during the first decade after the war, roughly 200,000 children were fathered in intimate contacts between German women and foreign soldiers. The experiences of these German occupation children (GOC) have been so far described in case reports and from historical perspective only. Research on psychosocial consequences of growing up as a GOC has been missing so far. This study examined traumatic experiences, posttraumatic stress disorder, somatization, and depression in GOC (N = 146) using self-report instruments: Posttraumatic Diagnostic Scale and Patient Health Questionnaire. Findings have then been compared with a representative birth cohort-matched sample from the German general population (N = 977). German occupation children showed significantly higher prevalence rates of most traumatic experiences, higher point prevalence rates of full and partial posttraumatic stress disorder, depression, and somatization than the control group. In summary, GOC often grew up under difficult conditions (e.g., poverty, single mothers, and stigmatization). Even decades later, they showed higher rates of different mental disorders and higher comorbidity. These findings underline the complex and long-term impact of their burdened social, financial, and familial conditions. The results underpin the importance of conceptualizing occupation children as a vulnerable group in postconflict settings.

  8. Hvad skal vi med skønlitteraturen?

    DEFF Research Database (Denmark)

    Bundsgaard, Jeppe; Oksbjerg, Marianne

    2012-01-01

    didaktiske læremidler, der produceres i disse år, lægges der ikke op til en udnyttelse af skønlitteraturens potentiale for at danne eleverne til demokratiske borgere. I denne artikel beskriver vi, hvad der er galt med læremidlerne. Desuden skitserer vi kriterier for formulering af elevopgaver, der lægger op...

  9. Detoxification of chromium (VI) in coastal water using lignocellulosic ...

    African Journals Online (AJOL)

    In the present study, attempts have been made to harness lignocellulosic agricultural waste material (bagasse) for the removal of chromium (VI) from highly saline coastal water used for aquacultural practices using brackish water. Five different products prepared from bagasse were evaluated for the detoxification of Cr(VI) ...

  10. Biosorption of chromium(VI) using immobilized Bacillius subtilis and ...

    African Journals Online (AJOL)

    Therefore, the batch removal of Cr (VI) from environment water bodies becomes necessary. Its removal from aqueous solution using immobilized Bacillus subtilis (IBBS), Pseudomonas aeruginosa (IPBS), mixed biomass (IMBS) and Alginate alone (IABS) was carried out. The conditions of influence of initial Cr (VI) ...

  11. Predicting chromium (VI) adsorption rate in the treatment of liquid ...

    African Journals Online (AJOL)

    The adsorption rate of chromium (VI) on commercial activated carbon during the treatment of the flocculation effluent of liquid-phase oil-based drill-cuttings has been investigated in terms of contact time and initial chromium (VI) ion concentration. Homogenizing 1 g of the activated carbon with 100 ml of the flocculation ...

  12. Kandinsky's "Composition VI": Heideggerian Poetry in Noah's Ark

    Science.gov (United States)

    Hall, Joshua M.

    2012-01-01

    The author will begin his investigation of Wassily Kandinsky's painting "Composition VI" with Kandinsky's own commentary on the painting. He will then turn to the analysis of Kandinsky and the "Compositions" in John Sallis's book "Shades." Using this analysis as his point of departure, the author will consider how "Composition VI" resonates with…

  13. Application of chromium stable isotopes to the evaluation of Cr(VI) contamination in groundwater and rock leachates from central Euboea and the Assopos basin (Greece)

    DEFF Research Database (Denmark)

    Economou-Eliopoulos, Maria; Frei, Robert; Atsarou, Cathy

    2014-01-01

    , stable chromium isotopes (expressed as δ53Cr values) were measured in groundwater and leachates in order to identify potential sources for Cr-contamination. The higher Cr(VI) concentrations in soil leachates compared to those in the rock pulp leachates potentially can be explained by the presence......Major and trace elements (a) in groundwater, ultramafic rocks from natural outcrops and soil samples from cultivated sites of Central Euboea and Assopos basin, and (b) in experimentally produced laboratory water leachates of rocks and soils were investigated by SEM/EDS, XRD and ICP/MS. In addition......(III). Using a Rayleigh distillation model and different fractionation factors of Cr(VI) reduction valid for aqueous Fe(II) and Fe(II)-bearing minerals, we calculate that more than ~ 53%, but maximum ~ 94%, of the originally mobile Cr(VI) pool was reduced to immobile Cr(III) in the waters investigated...

  14. The WMO RA VI Regional Climate Centre Network - a support to users in Europe

    Science.gov (United States)

    Rösner, S.

    2012-04-01

    Climate, like weather, has no limits. Therefore the World Meteorological Organization (WMO), a specialized United Nations organization, has established a three-level infrastructure to better serve its member countries. This structure comprises Global Producing Centres for Long-range Forecasts (GPCs), Regional Climate Centres (RCCs) and National Meteorological or Hydrometeorological Services (NMHSs), in most cases representing their countries in WMO governance bodies. The elements of this infrastructure are also part of and contribute to the Global Framework for Climate Services (GFCS) agreed to be established by World Climate Conference 3 (WCC-3) and last year's Sixteenth World Meteorological Congress (WMO Cg-XVI). RCCs are the core element of this infrastructure at the regional level and are being establish in all WMO Regional Associations (RAs), i.e. Africa (RA I); Asia (II); South America (III); North America, Central America and the Caribbean (IV); South-West Pacific (V); Europe (VI). Addressing inter-regional areas of common interest like the Mediterranean or the Polar Regions may require inter-regional RCCs. For each region the RCCs follow a user driven approach with regard to governance and structure as well as products generated for the users in the respective region. However, there are common guidelines all RCCs do have to follow. This is to make sure that services are provided based on best scientific standards, are routinely and reliably generated and made available in an operational mode. These guidelines are being developed within WMO and make use of decade-long experience gained in the business of operational weather forecast. Based on the requirements of the 50 member countries of WMO RA VI it was agreed to establish the WMO RCC as a network of centres of excellence that create regional products including long-range forecasts that support regional and national climate activities, and thereby strengthen the capacity of WMO Members in the region to

  15. Museo del oro: viñetas

    Directory of Open Access Journals (Sweden)

    Les Field

    2013-01-01

    Full Text Available En enero de 2011 convocamos a un grupo internacional de académicos/activistas para discutir en Colombia las complejidades de la relación entre arqueología, excavaciones “ilícitas”, museos y comunidades indígenas desde una mirada comparativa. El taller de tres días tuvo lugar en Bogotá y Villa de Leyva. Uno de los eventos programados durante los dos días de la parte bogotana del taller fue una visita al Museo del Oro. En el restaurante del museo conversamos sobre lo que acabábamos de ver, sentir y pensar, y surgieron estas impresiones en las que el estupor convive con un fuerte deseo por decir algo. En Villa de Leyva nació la idea de que cada uno de nosotros transcribiera sus emociones en formato de viñeta.

  16. A Video Tour through ViSta 6.4

    Directory of Open Access Journals (Sweden)

    J. Gabriel Molina

    2004-12-01

    Full Text Available This paper offers a visual tour throughout ViSta 6.4, a freeware statistical program based on Lisp-Stat and focused on techniques for statistical visualization (Young 2004. This travel around ViSta is based on screen recordings that illustrate the main features of the program in action. The following aspects of ViSta 6.4 are displayed: the program's interface (ViSta's desktop, menubar and pop-up menus, help system; its data management capabilities (data input and editing, data transformations; features associated to data analysis (data description, statistical modeling; and the options for Lisp-Stat development in ViSta. The video recordings associated to this tour (.wmv files can be visualized at http://www.jstatsoft.org/v13/i08/ using the Internet Explorer navigator, or by clicking on the figures in the paper.

  17. Biosorption of uranium (VI) by immobilized Aspergillus fumigatus beads

    Energy Technology Data Exchange (ETDEWEB)

    Wang Jingsong, E-mail: xhwjs@163.co [School of Urban Construction, University of South China, 28 West Changsheng Road, Hengyang, Hunan 421001 (China) and Hunan Key Laboratory of Pollution Control and Resource Reuse, University of South China, Henyang, Hunan 421001 (China); Hu Xinjiang [School of Urban Construction, University of South China, 28 West Changsheng Road, Hengyang, Hunan 421001 (China); College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Liu Yunguo [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Xie Shuibo [School of Urban Construction, University of South China, 28 West Changsheng Road, Hengyang, Hunan 421001 (China); Hunan Key Laboratory of Pollution Control and Resource Reuse, University of South China, Henyang, Hunan 421001 (China); Bao Zhenglei [School of Urban Construction, University of South China, 28 West Changsheng Road, Hengyang, Hunan 421001 (China)

    2010-06-15

    Biosorption of uranium (VI) ions by immobilized Aspergillus fumigatus beads was investigated in a batch system. The influences of solution pH, biosorbent dose, U (VI) concentration, and contact time on U (VI) biosorption were studied. The results indicated that the adsorption capacity was strongly affected by the solution pH, the biosorbent dose and initial U (VI) concentration. Optimum biosorption was observed at pH 5.0, biosrobent dose (w/v) 2.5%, initial U (VI) concentration 60 mg L{sup -1}. Biosorption equilibrium was established in 120 min. The adsorption process conformed to the Freunlich and Temkin isothermal adsorption models. The dynamic adsorption model conformed to pseudo-second order model.

  18. EXAFS investigation of uranium(VI) complexes formed at Bacillus cereus and Bacillus sphaericus surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Hennig, C.; Panak, P.J.; Reich, T.; Rossberg, A.; Raff, J.; Selenska-Pobell, S.; Bernhard, G.; Nitsche, H. [Inst. of Radiochemistry, Forschungszentrum Rossendorf, Dresden (Germany); Matz, W. [Inst. of Ion Beam Physics and Materials Research, Forschungszentrum Rossendorf, Dresden (Germany); Bucher, J.J. [Lawrence Berkeley National Lab., CA (United States)

    2001-07-01

    Uranium(VI) complex formation at vegetative cells and spores of Bacillus cereus and Bacillus sphaericus was studied using uranium L{sub II}-edge and L{sub III}-edge extended X-ray absorption fine structure (EXAFS) spectroscopy. A comparison of the measured equatorial U-O distances and other EXAFS structural parameters of uranyl species formed at the Bacillus strains with those of the uranyl structure family indicates that the uranium is predominantly bound as uranyl complexes with phosphoryl residues. (orig.)

  19. Investigation of uranium (VI) adsorption by polypyrrole

    Energy Technology Data Exchange (ETDEWEB)

    Abdi, S. [Faculty of Chemical, Petroleum and Gas Engineering, Semnan University, Semnan 35195-363 (Iran, Islamic Republic of); Nasiri, M., E-mail: mnasiri@semnan.ac.ir [Faculty of Chemical, Petroleum and Gas Engineering, Semnan University, Semnan 35195-363 (Iran, Islamic Republic of); Mesbahi, A. [Faculty of Chemical, Petroleum and Gas Engineering, Semnan University, Semnan 35195-363 (Iran, Islamic Republic of); Khani, M.H. [Nuclear Fuel Cycle Research School, Nuclear Science and Technology Research Institute, Tehran, 14395-836 (Iran, Islamic Republic of)

    2017-06-15

    Highlights: • The adsorbent (polypyrrole) was synthesized by a chemical method using PEG, DBSNa and CTAB as the surfactant. • The solution pH was one of the most important parameters affecting the adsorption of uranium. • The CTAB provided higher removal percentage compared with the other surfactants. • The maximum adsorption capacity obtained from Langmuir isotherm was 87.72 mg/g. • The pseudo second-order model fitted well with the adsorption kinetic of polypyrrole to uranium. - Abstract: The purpose of this study was to investigate the adsorption of uranium (VI) ions on the polypyrrole adsorbent. Polypyrrole was synthesized by a chemical method using polyethylene glycol, sodium dodecylbenzenesulfonate, and cetyltrimethylammonium bromide as the surfactant and iron (III) chloride as an oxidant in the aqueous solution. The effect of various surfactants on the synthesized polymers and their performance as the uranium adsorbent were investigated. Adsorbent properties were characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) techniques. The effect of different parameters such as pH, contact time, initial metal ion concentrations, adsorbent dose, and the temperature was investigated in the batch system for uranium adsorption process. It has been illustrated that the adsorption equilibrium time is 7 min. The results showed that the Freundlich model had the best agreement and the maximum adsorption capacity of polypyrrole for uranium (VI) was determined 87.72 mg/g from Langmuir isotherm. In addition, the mentioned adsorption process was fast and the kinetic data were fitted to the Pseudo first and second order models. The adsorption kinetic data followed the pseudo-second-order kinetic model. Moreover, the thermodynamic parameters ΔG{sup 0}, ΔH{sup 0} and ΔS{sup 0} showed that the uranium adsorption process by polypyrrole was endothermic and spontaneous.

  20. Chromium released from leather - I: exposure conditions that govern the release of chromium(III) and chromium(VI).

    Science.gov (United States)

    Hedberg, Yolanda S; Lidén, Carola; Odnevall Wallinder, Inger

    2015-04-01

    Approximately 1-3% of the adult population in Europe is allergic to chromium (Cr). A new restriction in REACH (Registration, Evaluation, Authorization and Restriction of Chemicals) based on the ISO 17075 standard has recently been adopted in the EU to limit Cr(VI) in consumer and occupational leather products. The aim of this study was to critically assess key experimental parameters in this standard on the release of Cr(III) and Cr(VI) and their relevance for skin exposure. Four differently tanned, unfinished, leather samples were systematically investigated for their release of Cr(III) and Cr(VI) in relation to surface area, key exposure parameters, temperature, ultraviolet irradiation, and time. Although the total release of Cr was largely unaffected by all investigated parameters, except exposure duration and temperature, the Cr oxidation state was highly dynamic, with reduced amounts of released Cr(VI) with time, owing to the simultaneous release of reducing agents from the leather. Significantly more Cr(III) than Cr(VI) was released from the Cr-tanned leather for all conditions tested, and it continued to be released in artificial sweat up to at least 1 week of exposure. Several parameters were identified that influenced the outcome of the ISO 17075 test. © 2015 The Authors. Contact Dermatitis published by John Wiley & Sons Ltd.

  1. Chromium released from leather – I: exposure conditions that govern the release of chromium(III) and chromium(VI)

    Science.gov (United States)

    Hedberg, Yolanda S; Lidén, Carola; Odnevall Wallinder, Inger

    2015-01-01

    Background Approximately 1–3% of the adult population in Europe is allergic to chromium (Cr). A new restriction in REACH (Registration, Evaluation, Authorization and Restriction of Chemicals) based on the ISO 17075 standard has recently been adopted in the EU to limit Cr(VI) in consumer and occupational leather products. Objectives The aim of this study was to critically assess key experimental parameters in this standard on the release of Cr(III) and Cr(VI) and their relevance for skin exposure. Material and methods Four differently tanned, unfinished, leather samples were systematically investigated for their release of Cr(III) and Cr(VI) in relation to surface area, key exposure parameters, temperature, ultraviolet irradiation, and time. Results Although the total release of Cr was largely unaffected by all investigated parameters, except exposure duration and temperature, the Cr oxidation state was highly dynamic, with reduced amounts of released Cr(VI) with time, owing to the simultaneous release of reducing agents from the leather. Significantly more Cr(III) than Cr(VI) was released from the Cr-tanned leather for all conditions tested, and it continued to be released in artificial sweat up to at least 1 week of exposure. Conclusions Several parameters were identified that influenced the outcome of the ISO 17075 test. PMID:25653094

  2. Efficacy and immunogenicity of a Vi-tetanus toxoid conjugate vaccine in the prevention of typhoid fever using a controlled human infection model of Salmonella Typhi: a randomised controlled, phase 2b trial.

    Science.gov (United States)

    Jin, Celina; Gibani, Malick M; Moore, Maria; Juel, Helene B; Jones, Elizabeth; Meiring, James; Harris, Victoria; Gardner, Jonathan; Nebykova, Anna; Kerridge, Simon A; Hill, Jennifer; Thomaides-Brears, Helena; Blohmke, Christoph J; Yu, Ly-Mee; Angus, Brian; Pollard, Andrew J

    2017-12-02

    completed challenge (31 in the control group, 35 in the Vi-PS group, and 37 in the Vi-TT group) and were included in the per-protocol population. The composite criteria for typhoid diagnosis was met in 24 (77%) of 31 participants in the control group, 13 (35%) of 37 participants in the Vi-TT group, and 13 (35%) of 35 participants in the Vi-PS group to give vaccine efficacies of 54·6% (95% CI 26·8-71·8) for Vi-TT and 52·0% (23·2-70·0) for Vi-PS. Seroconversion was 100% in Vi-TT and 88·6% in Vi-PS participants, with significantly higher geometric mean titres detected 1-month post-vaccination in Vi-TT vaccinees. Four serious adverse events were reported during the conduct of the study, none of which were related to vaccination (one in the Vi-TT group and three in the Vi-PS group). Vi-TT is a highly immunogenic vaccine that significantly reduces typhoid fever cases when assessed using a stringent controlled model of typhoid infection. Vi-TT use has the potential to reduce both the burden of typhoid fever and associated health inequality. The Bill & Melinda Gates Foundation and the European Commission FP7 grant, Advanced Immunization Technologies (ADITEC). Copyright © 2017 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.

  3. ADSORPTION OF Cr(VI ON BLACK WATER

    Directory of Open Access Journals (Sweden)

    Rasti Januarita

    2010-06-01

    Full Text Available The effect of initial concentration of Cr(VI on adsorption to black water of Gambut, District of Banjar, South Borneo has been investigated, as well as interaction between Cr(VI species and functional black water organic fraction. The initial work was optimization of Cr(VI determination using UV-Visible Spectrophotometry with diphenylcarbacide as complexing agent and preparation of black water using mixture of 2% HCl and 5% HF with HCl-HF ratio of 1 : 1 (v/v. The quantity of Cr(VI species adsorbed on black water was calculated by determining the amount of Cr(VI species in solution before and after interaction. The functional groups in interaction between Cr(VI species and black water organic fraction was studied qualitatively using infrared spectroscopy. The results showed that optimum condition for Cr(VI species analysis using UV-Visible spectrophotometry with diphenylcarbacide as complexing agent was at wave length of 540 nm, pH 1,5, 15 - 60 minutes at which complex remain stable, and minimum mol ratio of diphenylcarbacide : Cr(VI 45 : 1, and has a sensitivity of 1.134 mg/L and detection limit of 0.00495 mg/L. The analysis was not affected by the presence of Cr(III in concentration less than 40 times of Cr(VI concentration. After treatment with HCl-HF the quantity of black water organic fraction showing humic acid properties decreased 0,1998 percent. Organic fraction of black water used adsorpted Cr(VIwith capacity of 4,050 mg/g.   Keywords: Adsorption, Cr(VI, Black Water

  4. Technology-derived storage solutions for stabilizing insulin in extreme weather conditions I: the ViViCap-1 device.

    Science.gov (United States)

    Pfützner, Andreas; Pesach, Gidi; Nagar, Ron

    2017-06-01

    Injectable life-saving drugs should not be exposed to temperatures 30°C/86°F. Frequently, weather conditions exceed these temperature thresholds in many countries. Insulin is to be kept at 4-8°C/~ 39-47°F until use and once opened, is supposed to be stable for up to 31 days at room temperature (exception: 42 days for insulin levemir). Extremely hot or cold external temperature can lead to insulin degradation in a very short time with loss of its glucose-lowering efficacy. Combined chemical and engineering solutions for heat protection are employed in ViViCap-1 for disposable insulin pens. The device works based on vacuum insulation and heat consumption by phase-change material. Laboratory studies with exposure of ViViCap-1 to hot outside conditions were performed to evaluate the device performance. ViViCap-1 keeps insulin at an internal temperature change process and 'recharges' the device for further use. ViViCap-1 performed within its specifications. The small and convenient device maintains the efficacy and safety of using insulin even when carried under hot weather conditions.

  5. Simulating adsorption of U(VI) under transient groundwater flow and hydrochemistry – Physical versus non-equilibrium model

    Energy Technology Data Exchange (ETDEWEB)

    Greskowiak, Janek; Hay, Michael B.; Prommer, Henning; Liu, Chongxuan; Post, Vincent; Ma, Rui; Davis, James A.; Zheng, Chunmiao; Zachara, John M.

    2011-08-03

    Coupled intra-grain diffusional mass-transfer and non-linear surface complexation processes play an important role for the transport behaviour of U(VI) in contaminated aquifers. Two alternative model approaches for simulating these coupled processes have been analysed and compared: (i) the physical non-equilibrium approach that explicitly accounts for aqueous speciation and instantaneous surface complexation reactions in the intra-grain regions and approximates the diffusive mass exchange between the immobile intra-grain pore water and the advective pore water as multi-rate 1st-order mass transfer and (ii) the chemical non-equilibrium approach that approximates the diffusion-limited intra-grain surface complexation reactions by a set of multiple 1st-order surface complexation reaction kinetics, thereby eliminating the explicit treatment of aqueous speciation in the intra grain pore water. Model comparison has been carried out for column and field scale scenarios, representing the highly transient hydrological and geochemical conditions in the U(VI)-contaminated aquifer at the Hanford 300A site, Washington, USA. It was found that the response of apparent U(VI) adsorption/desorption kinetic behaviour to hydrogeochemically induced changes in U(VI) sorption strength is more pronounced in the physical than in the chemical non-equilibrium model. The magnitude of the differences in model behaviour depends particularly on the degree of disequilibrium between the advective and immobile phase U(VI) concentrations. While a clear difference in U(VI) transport behaviour between the two models was noticeable for the column-scale scenarios, only minor differences were found for the Hanford 300A field scale scenarios, where the model-generated disequilibrium conditions were less pronounced as a result of high frequent groundwater flow reversals.

  6. Effect of anthropogenic organic complexants on the solubility of Ni, Th, U(IV) and U(VI)

    Energy Technology Data Exchange (ETDEWEB)

    Felipe-Sotelo, M., E-mail: m.felipe-sotelo@lboro.ac.uk [Department of Chemistry, Loughborough University, LE11 3TU Loughborough, Leicestershire (United Kingdom); Edgar, M. [Department of Chemistry, Loughborough University, LE11 3TU Loughborough, Leicestershire (United Kingdom); Beattie, T. [MCM Consulting. Täfernstrasse 11, CH 5405 Baden-Dättwil (Switzerland); Warwick, P. [Enviras Ltd., LE11 3TU Loughborough, Leicestershire (United Kingdom); Evans, N.D.M.; Read, D. [Department of Chemistry, Loughborough University, LE11 3TU Loughborough, Leicestershire (United Kingdom)

    2015-12-30

    Highlights: • Citrate increases the solubility of Ni, Th and U between 3 and 4 orders of magnitude. • Theophrastite is the solubility controlling phase of Ni in 95%-saturated Ca(OH){sub 2}. • U(VI) and Ni may form Metal-citrate-OH complexes stabilised by the presence of Ca{sup 2+}. - Abstract: The influence of anthropogenic organic complexants (citrate, EDTA and DTPA from 0.005 to 0.1 M) on the solubility of nickel(II), thorium(IV) and uranium (U(IV) and U(VI)) has been studied. Experiments were carried out in 95%-saturated Ca(OH){sub 2} solutions, representing the high pH conditions anticipated in the near field of a cementitious intermediate level radioactive waste repository. Results showed that Ni(II) solubility increased by 2–4 orders of magnitude in the presence of EDTA and DTPA and from 3 to 4 orders of magnitude in the case of citrate. Citrate had the greatest effect on the solubility of Th(IV) and U(IV)/(VI). XRD and SEM analyses indicate that the precipitates are largely amorphous; only in the case of Ni(II), is there some evidence of incipient crystallinity, in the form of Ni(OH){sub 2} (theophrastite). A study of the effect of calcium suggests that U(VI) and Ni(II) may form metal-citrate-OH complexes stabilised by Ca{sup 2+}. Thermodynamic modelling underestimates the concentrations in solution in the presence of the ligands for all the elements considered here. Further investigation of the behaviour of organic ligands under hyperalkaline conditions is important because of the use of the thermodynamic constants in preparing the safety case for the geological disposal of radioactive wastes.

  7. Uranium(VI) interactions with mackinawite in the presence and absence of bicarbonate and oxygen

    Science.gov (United States)

    Gallegos, Tanya J.; Fuller, Christopher C.; Webb, Samuel M.; Betterton, William J.

    2013-01-01

    Mackinawite, Fe(II)S, samples loaded with uranium (10-5, 10-4, and 10-3 mol U/g FeS) at pH 5, 7, and 9, were characterized using X-ray absorption spectroscopy and X-ray diffraction to determine the effects of pH, bicarbonate, and oxidation on uptake. Under anoxic conditions, a 5 g/L suspension of mackinawite lowered 5 × 10-5 M uranium(VI) to below 30 ppb (1.26 × 10-7 M) U. Between 82 and 88% of the uranium removed from solution by mackinawite was U(IV) and was nearly completely reduced to U(IV) when 0.012 M bicarbonate was added. Near-neighbor coordination consisting of uranium–oxygen and uranium-uranium distances indicates the formation of uraninite in the presence and absence of bicarbonate, suggesting reductive precipitation as the dominant removal mechanism. Following equilibration in air, mackinawite was oxidized to mainly goethite and sulfur and about 76% of U(IV) was reoxidized to U(VI) with coordination of uranium to axial and equatorial oxygen, similar to uranyl. Additionally, uranium-iron distances, typical of coprecipitation of uranium with iron oxides, and uranium-sulfur distances indicating bidentate coordination of U(VI) to sulfate were evident. The affinity of mackinawite and its oxidation products for U(VI) provides impetus for further study of mackinawite as a potential reactive medium for remediation of uranium-contaminated water.

  8. Modulus of elasticity, creep and shrinkage of concrete, phase II : part 1, creep study, final report.

    Science.gov (United States)

    2009-10-01

    A laboratory testing program was performed to evaluate the physical and mechanical properties of typical Class II, IV, V, and VI concrete mixtures made with a Miami Oolite limestone, a Georgia granite, and a lightweight aggregate Stalite, including c...

  9. Effects of citrate on hexavalent chromium reduction by structural Fe(II) in nontronite.

    Science.gov (United States)

    Liu, Xiaolei; Dong, Hailiang; Yang, Xuewei; Kovarik, Libor; Chen, Yu; Zeng, Qiang

    2018-02-05

    Previous studies have shown that organic ligands could influence Cr(VI) reduction by aqueous Fe(2+) and pyrite. In this study, the effects of citrate on Cr(VI) reduction by structural Fe(II) in nontronite (NAu-2) were investigated at pH 6. Our results showed that the presence of citrate decreased the rate but increased the amount of Cr(VI) reduction. The decreased rate was likely due to competitive sorption of citrate and anionic dichromate (Cr2O7(-)) to NAu-2 surface sites, because sorption of dichromate appeared to be the first step for subsequent Cr(VI) reduction. The increased amount of Cr(VI) reduction was likely because citrate served as an additional electron donor to reduce Cr(VI) through ligand-metal electron transfer in the presence of soluble Fe(3+), which was possibly derived from dissolution of reduced NAu-2. Soluble Cr(III)-citrate complex was a possible form of reduced Cr(VI) when citrate was present. Without citrate, nanometer-sized Cr2O3 particles were the product of Cr(VI) reduction. Our study highlights the importance of citrate on Cr(VI) reduction and immobilization when iron-rich smectite is applied to treat Cr(VI) contaminant in organic carbon rich environments. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. The FUSE Survey of 0 VI in the Galactic Halo

    Science.gov (United States)

    Sonneborn, George; Savage, B. D.; Wakker, B. P.; Sembach, K. R.; Jenkins, E. B.; Moos, H. W.; Shull, J. M.

    2003-01-01

    This paper summarizes the results of the Far-Ultraviolet Spectroscopic Explorer (FUSE) program to study 0 VI in the Milky Way halo. Spectra of 100 extragalactic objects and two distant halo stars are analyzed to obtain measures of O VI absorption along paths through the Milky Way thick disk/halo. Strong O VI absorption over the velocity range from -100 to 100 km/s reveals a widespread but highly irregular distribution of O VI, implying the existence of substantial amounts of hot gas with T approx. 3 x 10(exp 5) K in the Milky Way thick disk/halo. The overall distribution of O VI is not well described by a symmetrical plane-parallel layer of patchy O VI absorption. The simplest departure from such a model that provides a reasonable fit to the observations is a plane-parallel patchy absorbing layer with an average O VI mid-plane density of n(sub 0)(O VI) = 1.7 x 10(exp -2)/cu cm, a scale height of approx. 2.3 kpc, and a approx. 0.25 dex excess of O VI in the northern Galactic polar region. The distribution of O VI over the sky is poorly correlated with other tracers of gas in the halo, including low and intermediate velocity H I, Ha emission from the warm ionized gas at approx. l0(exp 4) K, and hot X-ray emitting gas at approx. l0(exp 6) K . The O VI has an average velocity dispersion, b approx. 60 km/s and standard deviation of 15 km/s. Thermal broadening alone cannot explain the large observed profile widths. A combination of models involving the radiative cooling of hot fountain gas, the cooling of supernova bubbles in the halo, and the turbulent mixing of warm and hot halo gases is required to explain the presence of O VI and other highly ionized atoms found in the halo. The preferential venting of hot gas from local bubbles and superbubbles into the northern Galactic polar region may explain the enhancement of O VI in the North.

  11. Correlation between bulk- and surface chemistry of Cr-tanned leather and the release of Cr(III) and Cr(VI)

    Energy Technology Data Exchange (ETDEWEB)

    Hedberg, Yolanda S., E-mail: yolanda@kth.se [KTH Royal Institute of Technology, School of Chemical Science and Engineering, Department of Chemistry, Division of Surface and Corrosion Science, SE-10044 Stockholm (Sweden); Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-17177 Stockholm (Sweden); Lidén, Carola, E-mail: carola.liden@ki.se [Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-17177 Stockholm (Sweden); Odnevall Wallinder, Inger, E-mail: ingero@kth.se [KTH Royal Institute of Technology, School of Chemical Science and Engineering, Department of Chemistry, Division of Surface and Corrosion Science, SE-10044 Stockholm (Sweden)

    2014-09-15

    Graphical abstract: - Highlights: • Released reducing/complexing leather-specific species can reduce released Cr(VI). • No co-released species enable the formation of Cr(VI) in solution. • The major Cr species released from leather in phosphate buffer was Cr(III) (>82%). • No Cr(VI) was released into artificial sweat. - Abstract: About 1–3% of the adult general population in Europe is allergic to chromium (Cr). The assessment of the potential release of Cr(III) and Cr(VI) from leather is hence important from a human health and environmental risk perspective. The Cr(VI) content in leather was recently restricted in the European Union. The aim of this study was to assess possible correlations between the bulk and surface chemistry of leather, released Cr(III) and Cr(VI), and capacities of co-released leather specific species to reduce and complex released Cr. Four differently tanned leathers were characterized by scanning electron microscopy with energy dispersive spectroscopy, X-ray photoelectron spectroscopy, attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, and the diphenylcarbazide colorimetric method. Their characteristics were compared with results on Cr(III) and Cr(VI) release into artificial sweat (ASW, pH < 6.5) and phosphate buffer (PB, pH 7.5–8.0), measured by means of spectrophotometry and atomic absorption spectroscopy. Co-released leather-specific species were shown to reduce Cr(VI), both in ASW and in PB. Their reduction capacities correlated with findings of the surface content of Cr and of released Cr. Leather samples without this capacity, and with less aromatic surface groups visible by ATR-FTIR, revealed Cr(VI) both at the surface and in solution (PB)

  12. Enhanced biotic and abiotic transformation of Cr(vi) by quinone-reducing bacteria/dissolved organic matter/Fe(iii) in anaerobic environment.

    Science.gov (United States)

    Huang, Bin; Gu, Lipeng; He, Huan; Xu, Zhixiang; Pan, Xuejun

    2016-09-14

    This study investigated the simultaneous transformation of Cr(vi) via a closely coupled biotic and abiotic pathway in an anaerobic system of quinone-reducing bacteria/dissolved organic matters (DOM)/Fe(iii). Batch studies were conducted with quinone-reducing bacteria to assess the influences of sodium formate (NaFc), electron shuttling compounds (DOM) and the Fe(iii) on Cr(vi) reduction rates as these chemical species are likely to be present in the environment during in situ bioremediation. Results indicated that the concentration of sodium formate and anthraquinone-2-sodium sulfonate (AQS) had apparently an effect on Cr(vi) reduction. The fastest decrease in rate for incubation supplemented with 5 mM sodium formate and 0.8 mM AQS showed that Fe(iii)/DOM significantly promoted the reduction of Cr(vi). Presumably due to the presence of more easily utilizable sodium formate, DOM and Fe(iii) have indirect Cr(vi) reduction capability. The coexisting cycles of Fe(ii)/Fe(iii) and DOM(ox)/DOM(red) exhibited a higher redox function than the individual cycle, and their abiotic coupling action can significantly enhance Cr(vi) reduction by quinone-reducing bacteria.

  13. Reactivity enhancement of iron sulfide nanoparticles stabilized by sodium alginate: Taking Cr (VI) removal as an example.

    Science.gov (United States)

    Wu, Jun; Wang, Xian-Bin; Zeng, Raymond J

    2017-07-05

    The widespread distribution of chromium(VI) in the environment leads to groundwater contamination. The use of iron sulfide (FeS) to remove Cr(VI) has therefore been proposed. However, aggregation is one of the main problems associated with the use of FeS nanoparticles prepared by traditional methods In this study, we used sodium alginate (SA) to stabilize FeS nanoparticles (FeS-SA). SA could prevent aggregation of FeS by the concurrent electrostatic repulsion and steric hindrance. Homogeneously dispersed FeS-SA nanoparticles 100nm in diameter were observed. FeS-SA showed high efficiency in Cr(VI) removal, corresponding to an enhancement of efficiency from 65% (7.50mmol Cr(VI) per g FeS) to 100% (11.54mmol Cr per g FeS) relative to that achieved with naked FeS. Analysis of reaction products by X-ray diffraction and X-ray photoelectron spectroscopy revealed the co-existence of α-FeOOH, S8, and Cr(OH)3 that apparently were introduced by Fe(II), S(-II), and Cr(VI), respectively. In-depth analysis of the removal mechanism revealed that reduction and adsorption respectively account for 82% and 18% of the Cr removal. In addition, higher pH and CaCl2 concentration resulted in lower removal efficiency. This study provides a promising application of SA in enhancing FeS reactivity for the remediation of groundwater pollution. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Layered Double Hydroxides as Effective Adsorbents for U(VI and Toxic Heavy Metals Removal from Aqueous Media

    Directory of Open Access Journals (Sweden)

    G. N. Pshinko

    2013-01-01

    Full Text Available Capacities of different synthesized Zn,Al-hydrotalcite-like adsorbents, including the initial carbonate [Zn4Al2(OH12]·CO3·8H2O and its forms intercalated with chelating agents (ethylenediaminetetraacetic acid (EDTA, diethylenetriaminepentaacetic acid (DTPA, and hexamethylenediaminetetraacetic acid (HMDTA and heat-treated form Zn4Al2O7, to adsorb uranium(VI and ions of toxic heavy metals have been compared. Metal sorption capacities of hydrotalcite-like adsorbents have been shown to correlate with the stability of their complexes with the mentioned chelating agents in a solution. The synthesized layered double hydroxides (LDHs containing chelating agents in the interlayer space are rather efficient for sorption purification of aqueous media free from U(VI irrespective of its forms of natural abundance (including water-soluble bi- and tricarbonate forms and from heavy metal ions. [Zn4Al2(OH12]·EDTA·nH2O is recommended for practical application as one of the most efficient and inexpensive synthetic adsorbents designed for recovery of both cationic and particularly important anionic forms of U(VI and other heavy metals from aqueous media. Carbonate forms of LDHs turned out to be most efficient for recovery of Cu(II from aqueous media with pH0≥7 owing to precipitation of Cu(II basic carbonates and Cu(II hydroxides. Chromate ions are efficiently adsorbed from water only by calcinated forms of LDHs.

  15. VI Nukitsa konkurss lõppenud

    Index Scriptorium Estoniae

    2002-01-01

    Allk.: Eesti Lastekirjanduse Teabekeskus. Sisu : Nukitsa konkursi preemiad.Kirjanikud: I - Henno Käo ("Kusagil mujal"); II - Aidi Vallik ("Kuidas elad, Ann?"); III - Artur Jurin ("Piletijaht: uued segadused Kilulibeda teel").Kunstnikud: I - Karel Korp (Leelo Tungla ja Karel Korbi "Tema amet"); II - Edgar Valter ("Kuidas õppida vaatama?"); III - Artur Jurin - ("Piletijaht: uued segadused Kilulibeda teel"). Täiskasvanute küsitluse võitis nii teksti kui piltidega Ene-Maris ja Tarmo Tali "Tähtraamat. Aastaring Maarjamaal"

  16. Predicting outcome in the intensive care unit using scoring systems: is new better? A comparison of SAPS and SAPS II in a cohort of 1,393 patients. GiViTi Investigators (Gruppo Italiano per la Valutazione degli interventi in Terapia Intensiva). Simplified Acute Physiology Score.

    Science.gov (United States)

    Bertolini, G; D'Amico, R; Apolone, G; Cattaneo, A; Ravizza, A; Iapichino, G; Brazzi, L; Melotti, R M

    1998-09-01

    This study sought to compare the performance of the old and new versions of the Simplified Acute Physiology Score, SAPS and SAPS II, in classifying patients according to the risk of hospital mortality. To compare the performance of the two systems, measures of association between the scores and observed mortality were adopted, together with discrimination (area under the Receiver Operating Characteristics curve) and calibration (goodness-of-fit statistics) estimates. Subjects were 1,393 eligible patients recruited during 1 month in 1994. The outcome measure was vital status at hospital discharge. SAPS II was associated more strongly with hospital mortality than the earlier version. SAPS II also had better discrimination ability than SAPS (area under Receiver Operating Characteristics curve 0.80 versus 0.74) and predicted an overall number of deaths (416.5) closer to the observed figure (475) than SAPS (267.7). Conversely, neither SAPS nor SAPS II fitted our data. Both P values derived from goodness-of-fit statistics were lower than 0.05. SAPS II offers a real improvement compared with SAPS in its ability to explain hospital mortality, but its standard parameters do not fit our data from Italy. The role and impact of potential determinants of this lack of fit, such as random errors and confounders related to casemix and/or quality of care should be clarified before this scoring system be used outside formal research projects. Special caution is suggested when SAPS II is adopted to predict mortality to compare intensive care unit performance across different countries and systems of care.

  17. Adaptation and Latent Structure of the Swahili Version of Beck Depression Inventory-II in a Low Literacy Population in the Context of HIV

    NARCIS (Netherlands)

    Abubakar, A.; Kalu, Raphael Birya; Katana, Khamis; Kabunda, Beatrice; Hassan, Amin S.; Newton, Charles R.; Van de Vijver, Fons

    2016-01-01

    Objective We set out to adapt the Beck Depression Inventory (BDI)-II in Kenya and examine its factorial structure. Methods In the first phase we carried out in-depth interviews involving 29 adult members of the community to elicit their understanding of depression and identify aspects of the BDI-II

  18. Single-cell imaging and spectroscopic analyses of Cr(VI) reduction on the surface of bacterial cells.

    Science.gov (United States)

    Wang, Yuanmin; Sevinc, Papatya C; Belchik, Sara M; Fredrickson, Jim; Shi, Liang; Lu, H Peter

    2013-01-22

    We investigate the single-cell reduction of toxic Cr(VI) by the dissimilatory metal-reducing bacterium Shewanella oneidensis MR-1 (MR-1), an important bioremediation process, using Raman spectroscopy and scanning electron microscopy (SEM) combined with energy-dispersive X-ray spectroscopy (EDX). Our experiments indicate that the toxic, highly soluble Cr(VI) can be efficiently reduced to less toxic, nonsoluble Cr(2)O(3) nanoparticles by MR-1. Cr(2)O(3) is observed to emerge as nanoparticles adsorbed on the cell surface and its chemical nature is identified by EDX imaging and Raman spectroscopy. Co-localization of Cr(2)O(3) and cytochromes by EDX imaging and Raman spectroscopy suggests a terminal reductase role for MR-1 surface-exposed cytochromes MtrC and OmcA. Our experiments revealed that the cooperation of surface proteins OmcA and MtrC makes the reduction reaction most efficient, and the sequence of the reducing reactivity of MR-1 is wild type > single mutant ΔmtrC or mutant ΔomcA > double mutant (ΔomcA-ΔmtrC). Moreover, our results also suggest that direct microbial Cr(VI) reduction and Fe(II) (hematite)-mediated Cr(VI) reduction mechanisms may coexist in the reduction processes.

  19. Cinética e equilíbrio de adsorção dos oxiânions Cr (VI, Mo (VI e Se (VI pelo sal de amônio quaternário de quitosana Kinetics and equilibrium of adsorption of oxyanions Cr (VI, Mo (VI and Se (VI by quaternary ammonium chitosan salt

    Directory of Open Access Journals (Sweden)

    Viviane A. Spinelli

    2005-07-01

    Full Text Available O sal quaternário de quitosana foi sintetizado com cloreto de glicidil trimetil amônio. A modificação química foi caracterizada por espectrometria no IV, RMN de 13C e ¹H, e mmol/g de grupos quaternários presentes na matriz polimérica por condutimetria. A remoção de Cr (VI, Mo (VI e Se (VI, em meio aquoso, foi investigada em processo de batelada. A adsorção mostrou ser dependente do pH para o Cr (VI e Se (VI, com um pH ótimo de adsorção, entre 4,0 a 6,0. Para o Mo (VI a adsorção manteve-se quase constante no intervalo de pH entre 4,0 e 11,5. O modelo de isoterma de Langmuir descreveu melhor os dados de equilíbrio na faixa de concentração investigada. No presente estudo, um grama do sal quaternário de quitosana reticulado com glutaraldeído adsorveu 68,3 mg de Cr, 63,4 mg de Mo e 90,0 mg de Se. A velocidade de adsorção, no processo, segue a equação cinética de pseudo segunda-ordem, sendo que o equilíbrio para os três íons foi alcançado próximo aos 200 minutos. A análise dispersiva de raios-X para o Cr (VI mostrou que o principal mecanismo de adsorção é a troca iônica entre os íons Cl- da superfície do polímero pelos oxiânions. O trocador aniônico apresentou a seguinte ordem de seletividade: Cr (VI > Mo (VI > Se (VI.Quaternary chitosan salt was synthesized in the presence of glycidyl trimetyl ammonium chloride. The polymer was characterized by spectroscopic techniques: infrared, 13C and ¹H NMR, while the amount of quaternary ammonium groups was obtained by condutimetry. The removal of Cr (VI, Mo (VI and Se (VI from aqueous solutions was carried out in batch adsorption processes. The process seemed to be pH dependent for Cr (VI and Se (VI with an optimum pH ranging from 4.0 to 6.0; while for Mo (VI the adsorption remained almost constant within the range between 4.0 and 11.5. The Langmuir isotherm model provided the best fit of the equilibrium data over the whole concentration investigated. In the experiment

  20. On the passivation mechanism of Fe{sub 3}O{sub 4} nanoparticles during Cr(VI) removal from water: A XAFS study

    Energy Technology Data Exchange (ETDEWEB)

    Pinakidou, F., E-mail: fpina@physics.auth.gr [Aristotle University of Thessaloniki, Department of Chemical Engineering, Analytical Chemistry Laboratory, 54124 Thessaloniki (Greece); Katsikini, M. [Aristotle University of Thessaloniki, School of Physics, Section of Solid State Physics, 54124 Thessaloniki (Greece); Simeonidis, K.; Kaprara, E. [Aristotle University of Thessaloniki, Department of Chemical Engineering, Analytical Chemistry Laboratory, 54124 Thessaloniki (Greece); Paloura, E.C. [Aristotle University of Thessaloniki, School of Physics, Section of Solid State Physics, 54124 Thessaloniki (Greece); Mitrakas, M. [Aristotle University of Thessaloniki, Department of Chemical Engineering, Analytical Chemistry Laboratory, 54124 Thessaloniki (Greece)

    2016-01-01

    Graphical abstract: - Highlights: • Presence of Fe(II) even after high Cr-loading. • The vacancies in the γ-Fe{sub 2}O{sub 3} layer formed offer sites for Cr(III) sorption. • Cr(III) sorbs into the vacancies and Cr(VI) forms outer sphere complexes. • Increasing surface Cr(III) loading changes the polymerization of the Fe–O–Fe chains. • Cr(III) sorption modifies Fe{sub 3}O{sub 4} structure obstructing further Cr(VI) removal. - Abstract: X-Ray Absorption Spectroscopies (XAFS) are employed in order to gather a thorough insight on the uptake mechanism of Cr(VI) by Fe{sub 3}O{sub 4} nanoparticles under water treatment conditions. The XANES measurements identify that the reducing potential of Fe{sub 3}O{sub 4} activates the precipitation of Cr(VI) in the form of insoluble and non-toxic Cr(III). However, electron donation from Fe(II) is responsible for its gradual consumption, resulting in the presence of a surface maghemite layer and the formation of structural vacancies. EXAFS analysis reveal that adsorption of Cr(III)-oxyanions occurs on sorption sites provided by the vacancies in the maghemite layer, where Cr(III) is involved in a bidentate binuclear ({sup 2}E) geometry with Fe-octahedra while it also forms monodentate ({sup 1}V) complexes with the Fe(III)O{sub 4} tetrahedra. The surface maghemitization along with the reduced Cr(III) adsorption into the vacancies, tracks the degree of Cr-reduction, since this surface structural modifications hinder Cr(VI) access to the Fe(II) ions of the magnetite nanoparticles. Thus, high surface coverage leads to the passivation of the reduction ability since physisorbed Cr(VI) is also detected through the formation of outer sphere complexes.

  1. Vi behøver innovation

    DEFF Research Database (Denmark)

    McAloone, Tim C.

    2007-01-01

    . Især hvad angår vores forbrugsmønstre. Her er der behov for at kongeriget Danmark med sine 13 ton CO2-emission pr. person om året lytter. I landet hvor kraftvarmeproduk­tion, vindturbiner og industrial ecology i form af Kalundborg eksperimentet blev født, bør vi ikke også ride på denne nye miljøbølge......? Den amerikanske videnskabsmand Jeremy Rifkin beskriver i sin seneste bog, The European Dream, hvordan europæisk energipolitik, -forskning, -udvikling og relateret industri kan hjælpe os til at bremse vores for øjeblikket eksponentielt stigende CO2-produktion - og hvordan vores globaliseringstankegang...... rent faktisk kan fremme denne indsats. Den eneste udfordring er, at nogen skal igangsætte en økonomisk/industriel revolution, for at drømmen går i opfyldelse. Hvem skal tage ansvar for at sætte denne revolution i gang, og hvordan skal den opnås? Rifkin's patentløsning er inspirerende. Den er kort...

  2. [VI Symposium on "Chemistry of Proteolytic Enzymes"].

    Science.gov (United States)

    Rumsh, L D; Rotanova, T V

    2008-01-01

    The VI Symposium on the Chemistry of Proteolytic Enzymes took place in Moscow on April 23-25, 2007. It was dedicated to the memory of Corresponding Member of the Russian Academy of Sciences Vladimir Konstantinovich Antonov. At the symposium, 40 reports were delivered and 103 posters were presented in the following sections: (1) expression of genes, isolation and general characterization of proteases; (2) structure-function studies of proteases; (3) regulation of the activity of proteolytic enzymes; (4) regulatory functions of proteolytic enzymes; (5) proteases in biotechnology, protein engineering, and peptide synthesis; and (6) proteolysis and medicine. In addition to Russian scientists, researchers from the United States, the Netherlands, France, Ukraine, Belarus, Azerbaijan and Uzbekistan took part in the work of the symposium. Note that, in the five years since the V Symposium, the geography of Russian scientific centers working in the area of proteolysis has been considerably extended. Participating in the forum were researchers from, Novosibirsk, Tomsk, Penza, and Stavropol in addition to scientists from Moscow, Saint Petersburg, Petrozavodsk, Kazan, Nizhni Novgorod, and Krasnodar.

  3. Wind tunnel test of musi VI bridge

    Science.gov (United States)

    Permata, Robby; Andika, Matza Gusto; Syariefatunnisa, Risdhiawan, Eri; Hermawan, Budi; Noordiana, Indra

    2017-11-01

    Musi VI Bridge is planned to cross the Musi River in Palembang City, South Sumatera Province, Indonesia. The main span is a steel arch type with 200 m length and side span length is 75 m. Finite element analysis results showed that the bridge has frequency ratio for torsional and heaving mode (torsional frequency/heaving frequency)=1.14. This close to unity value rises concern about aerodynamic behaviour and stability of the bridge deck under wind loading. Sectional static and free vibration wind tunnel test were performed to clarify this phenomena in B2TA3 facility in Serpong, Indonesia. The test followed the draft of Guide of Wind Tunnel Test for Bridges developed by Indonesian Ministry of Public Works. Results from wind tunnel testing show that the bridge is safe from flutter instability and no coupled motion vibration observed. Therefore, low value of frequency ratio has no effect to aerodynamic behaviour of the bridge deck. Vortex-induced vibration in heaving mode occurred in relatively low wind velocity with permissible maximum amplitude value.

  4. Geochemical evaluation of Pabdeh Formation in Nosrat field, southeast Persian Gulf using Rock- Eval VI pyrolysis

    Directory of Open Access Journals (Sweden)

    mohammad sadeghi

    2015-02-01

    Full Text Available The present study was performed on 59 drillhole cuttings from Pabdeh Formation in Nosrat oil field using Rock- Eval VI pryrolysis. Geochemical analysis indicated that Pabdeh Formation possesses poor to good hydrocarbon potential. Plotting S1 against TOC suggests that samples were not affected by polluting substances such as crude oil and lubricants while drilling operation. Jones organic fancies diagram shows B-BC area indicating that Pabdeh Formation was deposited in marine anoxic to oxic environments. HI vesus Tmax shows that most samples initially have had type II kerogen and now reflecting a mixture of type II to III kerogen (capable of generating oil that have already entered oil generation window. In addition, S1+S2 versus TOC plot also suggests that Pabdeh Formation can be considered as a capable hydrocarbon generating source rock in the study area.

  5. Geochemical evaluation of Pabdeh Formation in Nosrat field, southeast Persian Gulf using Rock- Eval VI pyrolysis

    Directory of Open Access Journals (Sweden)

    Biuk ghorbani

    2015-01-01

    Full Text Available The present study was performed on 59 drillhole cuttings from Pabdeh Formation in Nosrat oil field using Rock- Eval VI pryrolysis. Geochemical analysis indicated that Pabdeh Formation possesses poor to good hydrocarbon potential. Plotting S1 against TOC suggests that samples were not affected by polluting substances such as crude oil and lubricants while drilling operation. Jones organic fancies diagram shows B-BC area indicating that Pabdeh Formation was deposited in marine anoxic to oxic environments. HI vesus Tmax shows that most samples initially have had type II kerogen and now reflecting a mixture of type II to III kerogen (capable of generating oil that have already entered oil generation window. In addition, S1+S2 versus TOC plot also suggests that Pabdeh Formation can be considered as a capable hydrocarbon generating source rock in the study area.

  6. A Case of Aplasia Cutis Congenita Type VI: Bart Syndrome

    National Research Council Canada - National Science Library

    Yasmin Alfayez; Sahar Alsharif; Adel Santli

    2017-01-01

    Aplasia cutis congenita type VI, also known as Bart syndrome, is a rare genetic mechanobullous disorder characterized by congenital localized absence of skin, mucocutaneous blistering lesions, and nail abnormalities...

  7. Stark broadening parameter tables for F VI and Cl VII

    Directory of Open Access Journals (Sweden)

    Dimitrijević M.S.

    1998-01-01

    Full Text Available Using a semiclassical approach, we have calculated electron−, proton−, and He III−impact line widths and shifts for 2 F VI and 10 Cl VII multiplets as a function of temperature and perturber density.

  8. ALTERATION OF U(VI)-PHASES UNDER OXIDIZING CONDITIONS

    Energy Technology Data Exchange (ETDEWEB)

    A.P. Deditius; S. Utsunomiya; R.C. Ewing

    2006-02-21

    Uranium-(VI) phases are the primary alteration products of the UO{sub 2} in spent nuclear fuel and the UO{sub 2+x}, in natural uranium deposits. The U(VI)-phases generally form sheet structures of edge-sharing UO{sub 2}{sup 2+} polyhedra. The complexity of these structures offers numerous possibilities for coupled-substitutions of trace metals and radionuclides. The incorporation of radionuclides into U(VI)-structures provides a potential barrier to their release and transport in a geologic repository that experiences oxidizing conditions. In this study, we have used natural samples of UO{sub 2+x}, to study the U(VI)-phases that form during alteration and to determine the fate of the associated trace elements.

  9. INTELSAT VI artist concept drawing titled 'Ocean Bridge'

    Science.gov (United States)

    1992-01-01

    International Telecommunications Satellite Organization (INTELSAT) VI artist concept drawing titled 'Ocean Bridge' shows satellite built by Hughes Aircraft Company and owned and operated by INTELSAT, a 122-nation cooperative, orbiting the Earth.

  10. Mechanism of uranium (VI) removal by two anaerobic bacterial communities

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Monica [Centro de Ciencias do Mar, Universidade do Algarve, FCT-DQF (edificio 8), Campus de Gambelas, 8005-139 Faro (Portugal); Faleiro, Maria Leonor [IBB - Centro de Biomedicina Molecular e Estrutural, Universidade do Algarve, FCT, Campus de Gambelas, 8005-139 Faro (Portugal); Costa, Ana M. Rosa da [Centro de Investigacao em Quimica do Algarve, Universidade do Algarve, FCT, DQF, Campus de Gambelas, 8005-139 Faro (Portugal); Chaves, Sandra; Tenreiro, Rogerio [Universidade de Lisboa, Faculdade de Ciencias, Centro de Biodiversidade, Genomica Integrativa e Funcional (BioFIG), Campus de FCUL, Campo Grande, 1749-016 Lisboa (Portugal); Matos, Antonio Pedro [Servico de Anatomia Patologica, Hospital Curry Cabral, Lisboa (Portugal); Costa, Maria Clara, E-mail: mcorada@ualg.pt [Centro de Ciencias do Mar, Universidade do Algarve, FCT-DQF (edificio 8), Campus de Gambelas, 8005-139 Faro (Portugal)

    2010-12-15

    The mechanism of uranium (VI) removal by two anaerobic bacterial consortia, recovered from an uncontaminated site (consortium A) and other from an uranium mine (consortium U), was investigated. The highest efficiency of U (VI) removal by both consortia (97%) occurred at room temperature and at pH 7.2. Furthermore, it was found that U (VI) removal by consortium A occurred by enzymatic reduction and bioaccumulation, while the enzymatic process was the only mechanism involved in metal removal by consortium U. FTIR analysis suggested that after U (VI) reduction, U (IV) could be bound to carboxyl, phosphate and amide groups of bacterial cells. Phylogenetic analysis of 16S rRNA showed that community A was mainly composed by bacteria closely related to Sporotalea genus and Rhodocyclaceae family, while community U was mainly composed by bacteria related to Clostridium genus and Rhodocyclaceae family.

  11. Thermodynamical analysis of the fission product release in the ORNL VI-3 and VI-5 tests; Analyse thermodynamique du relachement des produits de fission dans les essais ORNL VI-3 et VI-5

    Energy Technology Data Exchange (ETDEWEB)

    Defoort, J.; Froment, K

    1998-06-01

    The thermodynamical equilibrium hypothesis has been applied to the tests ORNL (Oak Ridge National Laboratory) VI-3 and VI-5 (Vertical Induction heated), to study fission release products. Irradiated fuel samples were heated under oxidizing (VI-3) and reducing (VI-5) controlled atmosphere. They can be compared to the Vercors 4 and 5 tests. The thermodynamical calculus results of barium and ruthenium fission products release, agree in the lump with measures, whatever the gas phase nature. The strontium release calculus under reducing atmosphere, is largely upper than those measured and correctly evaluated under oxidizing atmosphere. These results confirm those obtained for Vercors 4 and 5 and show the interest of the select model. (A.L.B.)

  12. The value of APACHE II in predicting mortality after paraquat poisoning in Chinese and Korean population: A systematic review and meta-analysis.

    Science.gov (United States)

    Huang, Jianshu; Xuan, Dandan; Li, Xiuju; Ma, Li; Zhou, Yuanling; Zou, Hejian

    2017-07-01

    The Acute Physiology and Chronic Health Evaluation II (APACHE II) score is used to determine disease severity and predict outcomes in critically ill patients. However, the prognostic significance of APACHE after acute paraquat (PQ) poisoning remains unclear. The meta-analysis was aimed to study the value of APACHE II in predicting mortality in PQ-exposed Chinese and Korean patients. Databases that included PubMed, Embase, Cochrane Library, and the Chinese National Knowledge Infrastructure were searched through August 2016. Studies using APACHE II to predict mortality in PQ-poisoned patients were selected. The odds ratio and weighted mean difference (WMD) were used to pool binary and continuous data. Additionally, we aggregated sensitivity, specificity, and other measures of accuracy. Statistical analyses were made using the Stata V.13.0 software. This study included 29 studies, and 25 studies evaluated APACHE II scores on admission. Pooled data showed that survivors had significantly lower total scores than nonsurvivors (WMD = -7.29, and I = 98.2%, both P APACHE II score ≥5 for predicting mortality was 75% and the pooled specificity was 86%. The positive likelihood ratio (PLR) was 5.3 and the negative likelihood ratio (NLR) was 0.29. The pooled sensitivity of an APACHE II score ≥10 for predicting mortality was 88% and the pooled specificity was 84%. The pooled PLR and NLR was 5.5 and 0.15, respectively. This study showed PQ-poisoned nonsurvivors had significantly higher APACHE II score than did survivors. APACHE II scores satisfactorily predicted mortality.

  13. VI Congrés Internacional de Conflictologia

    OpenAIRE

    Planell Estany, Josep A.

    2013-01-01

    Discurs del rector de la Universitat Oberta de Catalunya, Josep A. Planell Estany, amb motiu del VI Congrés Internacional de Conflictologia. Discurso del rector de la Universitat Oberta de Catalunya, Josep A. Planell Estany, con motivo del VI Congreso Internacional de Conflictología. Speech by the president of the Universitat Oberta de Catalunya, Josep A. Planell Estany,on the occasion of the Sixth International Congress on Conflict Resolution.

  14. Correlation between bulk- and surface chemistry of Cr-tanned leather and the release of Cr(III) and Cr(VI).

    Science.gov (United States)

    Hedberg, Yolanda S; Lidén, Carola; Odnevall Wallinder, Inger

    2014-09-15

    About 1-3% of the adult general population in Europe is allergic to chromium (Cr). The assessment of the potential release of Cr(III) and Cr(VI) from leather is hence important from a human health and environmental risk perspective. The Cr(VI) content in leather was recently restricted in the European Union. The aim of this study was to assess possible correlations between the bulk and surface chemistry of leather, released Cr(III) and Cr(VI), and capacities of co-released leather specific species to reduce and complex released Cr. Four differently tanned leathers were characterized by scanning electron microscopy with energy dispersive spectroscopy, X-ray photoelectron spectroscopy, attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, and the diphenylcarbazide colorimetric method. Their characteristics were compared with results on Cr(III) and Cr(VI) release into artificial sweat (ASW, pHleather-specific species were shown to reduce Cr(VI), both in ASW and in PB. Their reduction capacities correlated with findings of the surface content of Cr and of released Cr. Leather samples without this capacity, and with less aromatic surface groups visible by ATR-FTIR, revealed Cr(VI) both at the surface and in solution (PB). Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  15. Vi har intet lært - hvornår lærer vi det?

    DEFF Research Database (Denmark)

    Sodemann, Morten

    2016-01-01

    WHO anså fra i går ikke længere ebola for at være en trussel mod global folkesundhed, så fra i dag er kameraerne slukket i Vestafrika og vi er tilbage hvor vi startede. SDG målene skal have et dansk udtryk, men hvad er de danske kompetencer på globalt plan når sundhed ikke længere er en kerneakti......WHO anså fra i går ikke længere ebola for at være en trussel mod global folkesundhed, så fra i dag er kameraerne slukket i Vestafrika og vi er tilbage hvor vi startede. SDG målene skal have et dansk udtryk, men hvad er de danske kompetencer på globalt plan når sundhed ikke længere er en...

  16. Complexation of uranium(VI) with peptidoglycan.

    Science.gov (United States)

    Barkleit, Astrid; Moll, Henry; Bernhard, Gert

    2009-07-21

    We investigated the interaction of UO(2)(2+) with peptidoglycan (PG), the main part of the outer membrane of Gram-positive bacteria, by potentiometric titration and time-resolved laser-induced fluorescence spectroscopy (TRLFS) over a wide pH (2.0 to 9.0) and concentration range (10(-5) to 10(-4) M U(vi), 0.01 to 0.2 g L(-1) PG). With potentiometry two different dissociation constants for the carboxyl sites of glutamic acid and diaminopimelic acid (pK(a) = 4.55 +/- 0.02 and 6.31 +/- 0.01), and one averaged pK(a) for hydroxyl and amino groups (which are not distinguishable) (9.56 +/- 0.03) and the site densities could be identified. With potentiometry three different uranyl PG complexes were ascertained: two 1 : 1 uranyl carboxyl complexes R-COO-UO(2)(+), one with the glutamic acid carboxyl group (log beta(110) = 4.02 +/- 0.03), which has a very small formation ratio, and one with the diaminopimelic acid carboxyl group (log beta(110) = 7.28 +/- 0.03), and a mixed 1 : 1 : 1 complex with additional hydroxyl or amino coordination, R-COO-UO(2)((+))-A(i)-R (A(i) = NH(2) or O(-)) (log beta(1110) = 14.95 +/- 0.02). With TRLFS, also three, but different, species could be identified: a 1 : 1 uranyl carboxyl complex R-COO-UO(2)(+) (log beta(110) = 6.9 +/- 0.2), additionally a 1 : 2 uranyl carboxyl complex (R-COO)(2)-UO(2) (log beta(120) = 12.1 +/- 0.2), both with diaminopimelic acid carboxyl groups, and the mixed species R-COO-UO(2)((+))-A(i)-R (A(i) = NH(2) or O(-)) (log beta(1110) = 14.5 +/- 0.1). The results are in accordance within the errors of determination.

  17. Formaldehyde removal from wastewater and air by using UV, ferrate(VI) and UV/ferrate(VI).

    Science.gov (United States)

    Talaiekhozani, Amirreza; Salari, Malihe; Talaei, Mohammad Reza; Bagheri, Marzieh; Eskandari, Zeynab

    2016-12-15

    Formaldehyde removal from an air stream absorbed into a water stream in a packed bed continuously and then removed by employing a combination of UV and ferrate(VI) as a highly-powerful oxidant in a continuous stirred tank. In addition, the removal of formaldehyde from water was investigated in both batch and continuous modes. The results of the study performed on formaldehyde-contaminated water treatment can be used for both air and water treatment process design. The primary objective of this study is to compare the performance of using UV and ferrate(VI) individually with that of using UV/ferrate(VI) simultaneously to remove formaldehyde from both air and water. Moreover, the effects of several factors such as pH, ferrate(VI) concentration and temperature on formaldehyde removal from water using ferrate(VI) method were evaluated. The results of the current study in batch condition showed that the best initial pH and ferrate(VI) concentration to obtain the highest formaldehyde removal are 2 and 1 mg/l, respectively. The results of this part of research also reveal that temperatures rise from 25 °C to 50 °C increases formaldehyde removal from 69% to 97%; however, further increase in temperature has an adverse effect on removal efficiency. The combination of UV and ferrate(VI) enhances formaldehyde removal efficiency to very close to 100% within 35 min. In continuous air stream treatment, maximum formaldehyde removal of 94% was obtained by using a packed bed scrubber with gas over liquid flow rates ratio of 1.28 m(3)/m(3). Although the results of this study shows that ferrate(VI) method for removal of formaldehyde can be considered as a promising alternative for both water and air treatment, further economic studies are required for this process to be commercialized. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. PENGEMBANGAN MODEL PEMBELAJARAN BOLA VOLI MELALUI PERMAINAN TWONET BAGI SISWA KELAS VI SEKOLAH DASAR NEGERI 1 KEDUNGCINO KABUPATEN JEPARA

    Directory of Open Access Journals (Sweden)

    Wira Cita Panji Wicaksana

    2015-06-01

    Full Text Available The purpose of this research is to produce a product development model of learning through play volleyball twonet for students of classes VI Elementary School 1 Kedungcino Jepara district. Research Development refers to the development model of the Borg & Gall. The results of the study and discussion of expert evaluation data obtained an average of 70% (pretty good, with expert rician penjas 56% (pretty good, I 74% learning experts (good, and expert learning II 80% (good. While the results of a small pilot group obtained 84,33% (excellent and field-testing 88,96% (excellent. It can be concluded that the development model of learning through play volleyball twonet have met the learning needs so that it can be used for students of Grade VI Elementary School 1 Kedungcino Jepara district in 2012.

  19. Molecular evolution of type VI intermediate filament proteins

    Directory of Open Access Journals (Sweden)

    Vincent Michel

    2007-09-01

    Full Text Available Abstract Background Tanabin, transitin and nestin are type VI intermediate filament (IF proteins that are developmentally regulated in frogs, birds and mammals, respectively. Tanabin is expressed in the growth cones of embryonic vertebrate neurons, whereas transitin and nestin are found in myogenic and neurogenic cells. Another type VI IF protein, synemin, is expressed in undifferentiated and mature muscle cells of birds and mammals. In addition to an IF-typical α-helical core domain, type VI IF proteins are characterized by a long C-terminal tail often containing distinct repeated motifs. The molecular evolution of type VI IF proteins remains poorly studied. Results To examine the evolutionary history of type VI IF proteins, sequence comparisons, BLAST searches, synteny studies and phylogenic analyses were performed. This study provides new evidence that tanabin, transitin and nestin are indeed orthologous type VI IF proteins. It demonstrates that tanabin, transitin and nestin genes share intron positions and sequence identities, have a similar chromosomal context and display closely related positions in phylogenic analyses. Despite this homology, fast evolution rates of their C-terminal extremity have caused the appearance of repeated motifs with distinct biological activities. In particular, our in silico and in vitro analyses of their tail domain have shown that (avian transitin, but not (mammalian nestin, contains a repeat domain displaying nucleotide hydrolysis activity. Conclusion These analyses of the evolutionary history of the IF proteins fit with a model in which type VI IFs form a branch distinct from NF proteins and are composed of two major proteins: synemin and nestin orthologs. Rapid evolution of the C-terminal extremity of nestin orthologs could be responsible for their divergent functions.

  20. Expert recommendations for the laboratory diagnosis of MPS VI.

    Science.gov (United States)

    Wood, T; Bodamer, O A; Burin, M G; D'Almeida, V; Fietz, M; Giugliani, R; Hawley, S M; Hendriksz, C J; Hwu, W L; Ketteridge, D; Lukacs, Z; Mendelsohn, N J; Miller, N; Pasquali, M; Schenone, A; Schoonderwoerd, K; Winchester, B; Harmatz, P

    2012-05-01

    Mucopolysaccharidosis VI (MPS VI) is a lysosomal storage disease caused by a deficiency of N-acetylgalactosamine 4-sulfatase (arylsulfatase B, ASB). This enzyme is required for the degradation of dermatan sulfate. In its absence, dermatan sulfate accumulates in cells and is excreted in large quantities in urine. Specific therapeutic intervention is available; however, accurate and timely diagnosis is crucial for maximal benefit. To better understand the current practices for diagnosis and to establish diagnostic guidelines, an international MPS VI laboratory diagnostics scientific summit was held in February of 2011 in Miami, Florida. The various steps in the diagnosis of MPS VI were discussed including urinary glycosaminoglycan (uGAG) analysis, enzyme activity analysis, and molecular analysis. The following conclusions were reached. Dilute urine samples pose a significant problem for uGAG analysis and MPS VI patients can be missed by quantitative uGAG testing alone as dermatan sulfate may not always be excreted in large quantities. Enzyme activity analysis is universally acknowledged as a key component of diagnosis; however, several caveats must be considered and the appropriate use of reference enzymes is essential. Molecular analysis supports enzyme activity test results and is essential for carrier testing, subsequent genetic counseling, and prenatal testing. Overall the expert panel recommends caution in the use of uGAG screening alone to rule out or confirm the diagnosis of MPS VI and acknowledges enzyme activity analysis as a critical component of diagnosis. Measurement of another sulfatase enzyme to exclude multiple sulfatase deficiency was recommended prior to the initiation of therapy. When feasible, the use of molecular testing as part of the diagnosis is encouraged. A diagnostic algorithm for MPS VI is provided. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. Reactivity enhancement of iron sulfide nanoparticles stabilized by sodium alginate: Taking Cr (VI) removal as an example

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Jun; Wang, Xian-Bin; Zeng, Raymond J., E-mail: rzeng@ustc.edu.cn

    2017-07-05

    Highlights: • Sodium alginate can be used to stabilize FeS nanoparticles. • FeS-SA enhances Cr(VI) removal efficiency from 65% to 100% compared to naked FeS. • Reduction and adsorption respectively account for 82% and 18% of Cr removal by FeS-SA. • Analysis of reaction products reveals the co-existence of α-FeOOH, S{sub 8}, and Cr(OH){sub 3.} - Abstract: The widespread distribution of chromium(VI) in the environment leads to groundwater contamination. The use of iron sulfide (FeS) to remove Cr(VI) has therefore been proposed. However, aggregation is one of the main problems associated with the use of FeS nanoparticles prepared by traditional methods In this study, we used sodium alginate (SA) to stabilize FeS nanoparticles (FeS-SA). SA could prevent aggregation of FeS by the concurrent electrostatic repulsion and steric hindrance. Homogeneously dispersed FeS-SA nanoparticles 100 nm in diameter were observed. FeS-SA showed high efficiency in Cr(VI) removal, corresponding to an enhancement of efficiency from 65% (7.50 mmol Cr(VI) per g FeS) to 100% (11.54 mmol Cr per g FeS) relative to that achieved with naked FeS. Analysis of reaction products by X-ray diffraction and X-ray photoelectron spectroscopy revealed the co-existence of α-FeOOH, S{sub 8}, and Cr(OH){sub 3} that apparently were introduced by Fe(II), S(−II), and Cr(VI), respectively. In-depth analysis of the removal mechanism revealed that reduction and adsorption respectively account for 82% and 18% of the Cr removal. In addition, higher pH and CaCl{sub 2} concentration resulted in lower removal efficiency. This study provides a promising application of SA in enhancing FeS reactivity for the remediation of groundwater pollution.

  2. Q-Switched Nd:YAG Laser Removal of Facial Amateur Tattoos in Patients With Fitzpatrick Type VI: Case Series.

    Science.gov (United States)

    Haik, Josef; Kornhaber, Rachel; Harats, Moti; Israeli, Hadar; Orenstein, Arie

    2016-11-01

    Q-switched neodymium:YAG (Nd:YAG) lasers are reported to be gold standard for laser tattoo removal. In particular, the Q-switched Nd:YAG laser at 1064 nm is widely recognized for the removal of blue/black amateur tattoos. However, treatment modalities in Fitzpatrick Type VI skin carry a greater risk of complications including alterations in pigmentation compared to fairer skin (Fitzpatrick Type I-IV skin). Therefore, the aim of this case series was to describe with the use of the Q-Switched Nd:YAG laser, the removal of carbon-based amateur tattoos on patients with Fitzpatrick Type VI skin as an effective and safe method. Twenty- five patients with Fitzpatrick type VI skin, from Ethiopian origins, with facial tribal tattoos, were treated with the Q- Switched Nd:YAG laser at 1064 nm. Digital images were taken upon every treatment and the clearance rates of the tattoo was evalu- ated by imaging software. We observed an average tattoo clearance rate of 95% among the 45 facial tattoos in 25 patients presented in the case series with minimal pigmentary and textual changes evident. These positive aesthetic results have a signi cant psychosocial impact on the lives of those with Fitzpatrick Type VI skin, in particular the Ethiopian Jewish population. J Drugs Dermatol. 2016;15(11):1448-1452..

  3. Type VI Secretion System in Pseudomonas aeruginosa

    Science.gov (United States)

    Hachani, Abderrahman; Lossi, Nadine S.; Hamilton, Alexander; Jones, Cerith; Bleves, Sophie; Albesa-Jové, David; Filloux, Alain

    2011-01-01

    Pseudomonas aeruginosa is a Gram-negative bacterium causing chronic infections in cystic fibrosis patients. Such infections are associated with an active type VI secretion system (T6SS), which consists of about 15 conserved components, including the AAA+ ATPase, ClpV. The T6SS secretes two categories of proteins, VgrG and Hcp. Hcp is structurally similar to a phage tail tube component, whereas VgrG proteins show similarity to the puncturing device at the tip of the phage tube. In P. aeruginosa, three T6SSs are known. The expression of H1-T6SS genes is controlled by the RetS sensor. Here, 10 vgrG genes were identified in the PAO1 genome, among which three are co-regulated with H1-T6SS, namely vgrG1a/b/c. Whereas VgrG1a and VgrG1c were secreted in a ClpV1-dependent manner, secretion of VgrG1b was ClpV1-independent. We show that VgrG1a and VgrG1c form multimers, which confirmed the VgrG model predicting trimers similar to the tail spike. We demonstrate that Hcp1 secretion requires either VgrG1a or VgrG1c, which may act independently to puncture the bacterial envelope and give Hcp1 access to the surface. VgrG1b is not required for Hcp1 secretion. Thus, VgrG1b does not require H1-T6SS for secretion nor does H1-T6SS require VgrG1b for its function. Finally, we show that VgrG proteins are required for secretion of a genuine H1-T6SS substrate, Tse3. Our results demonstrate that VgrG proteins are not only secreted components but are essential for secretion of other T6SS substrates. Overall, we emphasize variability in behavior of three P. aeruginosa VgrGs, suggesting that, although very similar, distinct VgrGs achieve specific functions. PMID:21325275

  4. Sasse Modeling of First Cycle Neptunium (VI) Recovery Flowsheet

    Energy Technology Data Exchange (ETDEWEB)

    Laurinat, J. E. [Savannah River Site (SRS), Aiken, SC (United States)

    2006-04-01

    A flowsheet has been proposed to separate neptunium from solutions in H-Canyon Tanks 16.4, 12.5, and 11.7 in the First Cycle solvent extraction banks, in which cerium(IV) (Ce(IV)) serves as an agent to oxidize neptunium to neptunium(VI) (Np(VI)). A SASSE (Spreadsheet Algorithm for Stagewise Solvent Extraction) spreadsheet model indicates that the proposed flowsheet is a feasible method for separating neptunium and uranium from sulfates, thorium, and other metal impurities. The proposed flowsheet calls for stripping the sulfates, thorium, and other metal impurities into the 1AW stream and extracting and then stripping the neptunium and uranium into the 1BP stream. SASSE predicts that separation of thorium from the other actinides can be accomplished with actinide losses of 0.01% or less. It is assumed that other metal impurities such as iron, aluminum, and fission products will follow the thorium into 1AW. Due to an organic/aqueous distribution coefficient that is close to one, SASSE predicts that plutonium(VI) (Pu(VI)) is split between the A Bank and B Bank aqueous output streams, with 27% going to 1AW and 73% going to 1BP. An extrapolated distribution coefficient based on unvalidated Ce(IV) distribution measurements at a single nitrate concentration and a comparison with thorium(IV) (Th(IV)) distributions indicates that Ce(IV) could reflux in 1B Bank. If the Ce(IV) distribution coefficient is lower than would be predicted by this single point extrapolation, but still higher than the distribution coefficient for Th(IV), then Ce(IV) would follow Np(VI) and uranium(VI) (U(VI)) into 1BP. The SASSE model was validated using data from a 1964 oxidizing flowsheet for the recovery of Np(VI) in Second Cycle. For the proposed flowsheet to be effective in recovering neptunium, the addition of approximately 0.025 M ceric ammonium nitrate (Ce(NH4)2(NO3)6) to both the 1AF and 1AS streams is required to stabilize the neptunium in the +6

  5. Spin-flip-Raman studies of semimagnetic II-VI heterostructures; Spin-flip-Raman-Untersuchungen an semimagnetischen II-VI-Halbleiter-Quantentroegen und Volumenproben

    Energy Technology Data Exchange (ETDEWEB)

    Lentze, Michael

    2009-03-18

    In the present doctoral thesis, spin flip Raman studies of semimagnetic (Zn,Mn)Se samples were in the focus of interest. Quantum wells as well as bulk-like materials were investigated. The main goal was a better understanding of the exchange interaction behaviour of heavily n-doped semimagnetic samples. The influence of doping on the exchange interaction is of special relevance with regard to spintronics applications. Several series of high quality MBE-grown (Zn,Mn)Se-samples samples were available. (orig.)

  6. Integrated Cr(VI) removal using constructed wetlands and composting.

    Science.gov (United States)

    Sultana, Mar-Yam; Chowdhury, Abu Khayer Md Muktadirul Bari; Michailides, Michail K; Akratos, Christos S; Tekerlekopoulou, Athanasia G; Vayenas, Dimitrios V

    2015-01-08

    The present work was conducted to study integrated chromium removal from aqueous solutions in horizontal subsurface (HSF) constructed wetlands. Two pilot-scale HSF constructed wetlands (CWs) units were built and operated. One unit was planted with common reeds (Phragmites australis) and one was kept unplanted. Influent concentrations of Cr(VI) ranged from 0.5 to 10mg/L. The effect of temperature and hydraulic residence time (8-0.5 days) on Cr(VI) removal were studied. Temperature was proved to affect Cr(VI) removal in both units. In the planted unit maximum Cr(VI) removal efficiencies of 100% were recorded at HRT's of 1 day with Cr(VI) concentrations of 5, 2.5 and 1mg/L, while a significantly lower removal rate was recorded in the unplanted unit. Harvested reed biomass from the CWs was co-composted with olive mill wastes. The final product had excellent physicochemical characteristics (C/N: 14.1-14.7, germination index (GI): 145-157%, Cr: 8-10mg/kg dry mass), fulfills EU requirements and can be used as a fertilizer in organic farming. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Measuring disability across cultures — the psychometric properties of the WHODAS II in older people from seven low- and middle-income countries. The 10/66 Dementia Research Group population-based survey

    Science.gov (United States)

    Sousa, Renata M; Dewey, Michael E; Acosta, Daisy; Jotheeswaran, AT; Castro-Costa, Erico; Ferri, Cleusa P; Guerra, Mariella; Huang, Yueqin; Jacob, KS; Pichardo, Juana Guillermina Rodriguez; Ramírez, Nayeli Garcia; Rodriguez, Juan Llibre; Rodriguez, Marina Calvo; Salas, Aquiles; Sosa, Ana Luisa; Williams, Joseph; Prince, Martin J

    2010-01-01

    We evaluated the psychometric properties of the 12-item interviewer-administered screener version of the World Health Organization Disability Assessment Schedule – version II (WHODAS II) among older people living in seven low- and middle-income countries. Principal component analysis (PCA), confirmatory factor analysis (CFA) and Mokken analyses were carried out to test for unidimensionality, hierarchical structure, and measurement invariance across 10/66 Dementia Research Group sites. PCA generated a one-factor solution in most sites. In CFA, the two-factor solution generated in Dominican Republic fitted better for all sites other than rural China. The two factors were not easily interpretable, and may have been an artefact of differing item difficulties. Strong internal consistency and high factor loadings for the one-factor solution supported unidimensionality. Furthermore, the WHODAS II was found to be a ‘strong’ Mokken scale. Measurement invariance was supported by the similarity of factor loadings across sites, and by the high between-site correlations in item difficulties. The Mokken results strongly support that the WHODAS II 12-item screener is a unidimensional and hierarchical scale confirming to item response theory (IRT) principles, at least at the monotone homogeneity model level. More work is needed to assess the generalizability of our findings to different populations. Copyright © 2010 John Wiley & Sons, Ltd. PMID:20104493

  8. The prevalence of diabetes mellitus (DM) type II among Iranian elderly population and its association with other age-related diseases, 2012.

    Science.gov (United States)

    Taheri Tanjani, Parisa; Moradinazar, Mehdi; Esmail Mottlagh, Mohammad; Najafi, Farid

    2015-01-01

    DM type II is one of the most common chronic diseases. The objective of this study is to investigate the prevalence of DM and its association with other age-related diseases in Iran, 2012. In this cross-sectional study, people aged 60 years and over were selected using multistage sampling method. Mini-Nutritional Assessment (MNA), Activity of Daily Living (ADL), and Geriatric Depression Scale (GDS-15 items) questionnaires were used. History of common disorders was taken through self-report, medical records and the results of clinical examinations. A total of 1350 old people were studied. DM type II was found in 297 (22.0%) subjects and 371 (27.5%) of subjects were not aware of their DM status. Hypertension (55.6%), high serum cholesterol (51.8%), malnutrition (40.1%), Alzheimer's disease (16.9%), weight loss within past year (16.1%), weight gain within past year (11.7%), frailty (64.6%), insomnia (50.1%), and vision problems (62.6%) were significantly more common in diabetics. Those who were not aware of their status of DM either were between diabetics and non-diabetics or more similar to non-diabetics. Considering high prevalence of age-related diseases among Iranian elderly people, in particular women and those with DM type II, preventive measures are recommended so as to decrease and control DM type II and its consequent complications. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  9. New generation ion-imprinted nanocarrier for removal of Cr(VI) from wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Uygun, Murat, E-mail: muygun@adu.edu.tr [Adnan Menderes University, Kocarl Latin-Small-Letter-Dotless-I Vocational and Training School (Turkey); Feyzioglu, Esra; Oezcal Latin-Small-Letter-Dotless-I skan, Emir; Caka, Mueserref; Ergen, Aygen; Akgoel, Sinan [Ege University, Department of Biochemistry, Faculty of Science (Turkey); Denizli, Adil [Hacettepe University, Department of Chemistry, Faculty of Science (Turkey)

    2013-08-15

    The purpose of this study was to prepare a novel ion-imprinted nanoparticle to remove Cr(VI) ions from waste water. For this, Cr(VI) ions were complexed with 2-methacryloylamido histidine (MAH) and then Cr(VI)-imprinted poly(HEMAH) nanoparticles were synthesized by surfactant-free emulsion polymerization technique. The templates, Cr(VI) ions, were removed from the nanoparticles using 0.1 M of HNO{sub 3} solution. The specific surface area of the Cr(VI)-imprinted poly(HEMAH) nanoparticles was found to be 1,397.85 m{sup 2}/g, and the particle size was calculated as 155.3 nm. These Cr(VI)-imprinted nanoparticles were used for the adsorption/desorption of Cr(VI) ions from its aqueous solutions. The effects of initial Cr(VI) concentration and medium pH on the Cr(VI) adsorption capacity were also studied. The maximum adsorbed amount of Cr(VI) on the imprinted nanoparticles was found to be 3,830.58 mg/g nanoparticle in pH 4.0. In order to investigate the selectivity of the imprinted nanoparticle, adsorption studies were repeated using Cr(III) ions. The selectivity results demonstrated that Cr(VI)-imprinted poly(HEMAH) nanoparticles showed high affinity for the Cr(VI) ions than Cr(III). The Cr(VI)-imprinted nanoparticles were used several times without decreasing their Cr(VI) adsorption capacities.

  10. Isolation of a star-shaped uranium(V/VI) cluster from the anaerobic photochemical reduction of uranyl(VI)

    Energy Technology Data Exchange (ETDEWEB)

    Chatelain, Lucile; White, Sarah; Scopelliti, Rosario; Mazzanti, Marinella [Ecole Polytechnique Federale de Lausanne (EPFL) (Switzerland). Inst. de Sciences et Ingenierie Chimiques

    2016-11-07

    Actinide oxo clusters are an important class of compounds due to their impact on actinide migration in the environment. The photolytic reduction of uranyl(VI) has potential application in catalysis and spent nuclear fuel reprocessing, but the intermediate species involved in this reduction have not yet been elucidated. Here we show that the photolysis of partially hydrated uranyl(VI) in anaerobic conditions leads to the reduction of uranyl(VI), and to the incorporation of the resulting U{sup V} species into the stable mixed-valent star-shaped U{sup VI}/U{sup V} oxo cluster [U(UO{sub 2}){sub 5}(μ{sub 3}-O){sub 5}(PhCOO){sub 5}(Py){sub 7}]. This cluster is only the second example of a U{sup VI}/U{sup V} cluster and the first one associating uranyl groups to a non-uranyl(V) center. The U{sup V} center in 1 is stable, while the reaction of uranyl(V) iodide with potassium benzoate leads to immediate disproportionation and formation of the U{sub 12}{sup IV}U{sub 4}{sup V}O{sub 24} cluster {[K(Py)_2]_2[K(Py)]_2[U_1_6O_2_4(PhCOO)_2_4(Py)_2]}.

  11. Effects of citrate on hexavalent chromium reduction by structural Fe(II) in nontronite

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiaolei; Dong, Hailiang; Yang, Xuewei; Kovarik, Libor; Chen, Yu; Zeng, Qiang

    2018-02-01

    Iron-bearing clay minerals and organic matter are two important components in natural environments that influence hexavalent chromium (Cr(VI)) reduction. Previous studies have shown that organic ligands could influence Cr(VI) reduction by aqueous Fe2+ and pyrite. However, the effects of organic ligands on Cr(VI) reduction by structural Fe(II) in clays are not well understood. In this study, the effects of citrate on Cr(VI) reduction by nontronite (NAu-2) were investigated under near neutral pH condition (pH=6). Our results showed that the presence of citrate decreased the rate but increased the amount of Cr(VI) reduction by structural Fe(II) in NAu-2. The decreased reaction rate was likely due to competitive sorption of citrate and polyanionic dichromate (Cr2O7- ), because sorption of dichromate appeared to be the first step for subsequent Cr(VI) reduction. The increased amount of Cr(VI) reduction in the presence of citrate was likely because citrate provided additional reducing power through ligand-metal electron transfer in the presence of soluble Fe 3+ derived from dissolution of reduced NAu-2. Soluble Cr(III)-citrate complex was the possible form of reduced chromium when citrate was present. In contrast, nanometer-sized Cr2O3 particles were the product of Cr(VI) reduction by reduced NAu-2 without citrate. Our study highlights the importance of organic ligands on Cr(VI) reduction and immobilization when iron-bearing clay minerals are applied to treat Cr(VI) contaminant in organic matter rich environments.

  12. Sådan skaber vi mønsterbrydere

    DEFF Research Database (Denmark)

    Jensen, Bente

    2017-01-01

    Treårigt forskningsprojekt viser, at pædagoger og medhjælpere kan undersøtte alle børns trivsel og udvikling og dermed styrke udsatte børns ressourcer. det vil kjælpe med at bryde den sociale arv og forhindre, at vi reproducerer ulighed.......Treårigt forskningsprojekt viser, at pædagoger og medhjælpere kan undersøtte alle børns trivsel og udvikling og dermed styrke udsatte børns ressourcer. det vil kjælpe med at bryde den sociale arv og forhindre, at vi reproducerer ulighed....

  13. Sådan bekæmper vi skattely

    DEFF Research Database (Denmark)

    Christensen, Rasmus Corlin; Mondrup Pedersen, Mikkel

    2016-01-01

    I kampens hede er det belejligt at skyde skylden på Nordea og Mossack Fonseca, men skal vi skattely til livs, kræver det en mere omfattende reformation af det internationale skattesystem. Her er de tre største udfordringer......I kampens hede er det belejligt at skyde skylden på Nordea og Mossack Fonseca, men skal vi skattely til livs, kræver det en mere omfattende reformation af det internationale skattesystem. Her er de tre største udfordringer...

  14. Nonspecificity of bacterial reduction of Cr(VI)

    Energy Technology Data Exchange (ETDEWEB)

    Gvozdyak, P.I.; Mogilevich, N.F.; Ryl' skiy, A.F.; Grishchenko, N.I.

    1985-03-01

    Eight different genera of gram-positive and negative bacteria were tested for their ability to carry out reduction of Cr(VI) to Cr(III). The results demonstrated that in addition to Pseudomonas the other genera capable of similar enzymatic activity were Achromobacter, Bacillus and Micrococcus. These observations indicate that reduction of Cr(VI) is not a unique feature of Pseudomonas alone, and that the availability of other bacteria with similar metabolic potential expands the possibility of their utilization in water treatment and possibly in metallurgical enrichment biotechnology. 15 references.

  15. Human placental IGF-I and IGF-II expression: correlating maternal and infant anthropometric variables and micronutrients at birth in the Pakistani population.

    Science.gov (United States)

    Akram, S K; Akram, M; Bhutta, Z A; Soder, O

    2008-10-01

    To correlate infant birth weight with maternal and infant biometric data, including the expression of placental IGF-I and IGF-II at birth, and levels of serum zinc and ferritin. The data consisted of observations from 89 women from Karachi, Pakistan. Placental and cord blood samples were taken immediately following delivery and were subsequently divided into two groups, small and large for gestational age (SGA and LGA). The mean birth weight was 2.79 kg; the prevalence of SGA being 13.4% ( or =90th percentile). Placental IGF-I and IGF-II mRNA expression was greater in the LGA group (p importance of these growth factors for birth weight outcomes. The higher zinc levels in the LGA group also suggest the importance of this micronutrient in foetal growth. Our results suggest that growth problems have a multifactorial aetiology arising from within the infant rather than due to maternal constraint alone.

  16. Potential application of population models in the European ecological risk assessment of chemicals: II review of models and whether they can address the protection aims

    NARCIS (Netherlands)

    Galic, N.G.; Hommen, U.; Baveco, J.M.; Brink, van den P.J.

    2010-01-01

    Whereas current chemical risk assessment (RA) schemes within the European Union (EU) focus mainly on toxicity and bioaccumulation of chemicals in individual organisms, most protection goals aim at preserving populations of nontarget organisms rather than individuals. Ecological models are tools

  17. Potentially Traumatic Event Exposure, Posttraumatic Stress Disorder, and Axis I and II Comorbidity in a Population Based Study of Norwegian Young Adults

    Science.gov (United States)

    Amstadter, Ananda B.; Aggen, Steven H.; Knudsen, Gun Peggy; Reichborn-Kjennerud, Ted; Kendler, Kenneth S.

    2013-01-01

    Purpose Epidemiologic research on traumatic stress is limited in Norway. Prevalence and correlates of exposure to potentially traumatic events (PTEs) and Posttraumatic stress disorder (PTSD), and patterns of comorbidity with DSM-IV Axis I and II disorders were examined in an epidemiologic sample. Methods Demographics, PTEs, and resulting PTSD, and comorbid DSM-IV diagnoses were assessed in 2,794 members of the Norwegian Institute of Public Health Twin Panel. The sample was 37% male, with an average age of 28.2 years (SD=3.9). Results Approximately one-quarter of participants had lifetime PTE exposure; most PTEs were more common in men than in women. Lifetime prevalence of PTSD was 2.6%, and was significantly more common in women than men. Being female and type of PTE (both interpersonal and accidental traumatic events) were associated with increased PTSD symptoms, whereas higher education was associated with lower symptoms. PTSD was related to increased odds of most Axis I and II conditions. Conclusions PTE exposure and PTSD prevalence were lower than in the US, but comparable to other European countries. Sex differences replicated previous research. The relationship between PTSD and Borderline Personality Disorder was significantly stronger than the relationship between PTSD and any other Axis II conditions. PMID:22782308

  18. Isolation and characterization of Cr(VI)-reducing actinomycetes from estuarine sediments.

    Science.gov (United States)

    Terahara, Takeshi; Xu, Xudan; Kobayashi, Takeshi; Imada, Chiaki

    2015-04-01

    Bioremediation technologies have strong potential use in the less costly and more environmentally friendly removal of highly toxic hexavalent-chromium (Cr(VI)) compared with physicochemical technologies. Several Cr(VI)-reducing bacteria have been isolated; however, there are few studies on Cr(VI)-resistant and Cr(VI)-reducing actinomycetes. In this study, Cr(VI)-reducing actinomycetes were screened from estuarine, marine, and terrestrial samples on the basis of Cr(VI)-resistant and Cr(VI)-reducing ability. Of the 80 Streptomyces-like strains isolated, 20 strains were found to be resistant to 50 mg/l of Cr(VI). In addition, two strains isolated from the estuarine sediment of Tokyo Bay were found to be resistant to a concentration of 150 mg/l of Cr(VI). Furthermore, one Cr(VI)-reducing strain was found to remove 60 mg/l of Cr(VI) within 1 week and was identified as Streptomyces thermocarboxydus based on 16S rRNA gene analysis. The comparative evaluation with the type strain S. thermocarboxydus NBRC 16323 showed that our isolated strain had higher ability to grow at 27 °C and reduce Cr(VI) at a NaCl concentration of 6.0 % at 27 °C compared with the type strain NBRC 16323. These results indicate that our isolated strain have a potential ability to remove Cr(VI) from contaminated, highly saline sources without heating.

  19. Adsorption Properties of Bentonite with In Situ Immobilized Polyaniline Towards Anionic Forms of Cr(VI, Mo(VI, W(VI, V(V

    Directory of Open Access Journals (Sweden)

    Kateryna RYABCHENKO

    2016-05-01

    Full Text Available A new composite material bentonite-PANI was synthesized by in situ immobilization of polyaniline (PANI on the surface of natural mineral bentonite. It was established as a result of the modification of bentonite a surface area and an interlayer distance of mineral decrease and particles of bentonite transformed of irregular shape with different porosity on irregularly shaped particles of smaller size. It has been found that the total Cr(VI ions extraction took place under the acid conditions (pH=1 – 2 and W(VI ions have been well adsorbed in the pH range from 1 to 8 by the composite bentonite-PANI unlike the initial mineral. Whereas adsorption of oxo anions of V(V and Mo(VI made up some 50%. It is proved that the in situ immobilization of bentonite by polyaniline leads to increasing the value of adsorption capacity towards the investigated ions compared with the initial mineral. It was established that the adsorption properties of the synthesized composite with respect to the studied oxo ions were worse than the adsorption properties of composite vermiculite-PANI, similar to the composite Sokyryntsyy clinoptilolite-PANI and better than composites of polyaniline with Podilskyy saponite and Karelian shungite.DOI: http://dx.doi.org/10.5755/j01.ms.22.2.6976

  20. Activation of the CXCR3 chemokine receptor through anchoring of a small molecule chelator ligand between TM-III, -IV, and -VI

    DEFF Research Database (Denmark)

    Rosenkilde, Mette M; Andersen, Michael B; Nygaard, Rie

    2006-01-01

    between the extracellular ends of transmembrane (TM) III and TM-IV to anchor aromatic chelators at a location corresponding to the presumed binding pocket for adrenergic receptor agonists. In this construct, free metal ions had no agonistic effect in accordance with the optimal geometry of the metal ion...... site in molecular models built over the inactive form of rhodopsin. In contrast, the aromatic chelators bipyridine or phenanthrolene in complex with Zn(II) or Cu(II) acted as potent agonists displaying signaling efficacies similar to or even better than the endogenous chemokine agonists. Molecular...... modeling and molecular simulations combined with mutational analysis indicated that the metal ion site-anchored chelators act as agonists by establishing an aromatic-aromatic, second-site interaction with TyrVI:16 on the inner face of TM-VI. It is noteworthy that this interaction required...

  1. Group IB Organometallic Chemistry XXXIV: Thermal behavior and chemical reactivity of tetranuclear Me2N-substituted diarylpropenylcopper-copper anion (Vi2Cu4X2) and mixed diarylpropenyl/organocopper (Vi2Cu4R2) compounds

    NARCIS (Netherlands)

    Koten, G. van; Hoedt, R.W.M. ten; Noltes, J.G.

    1980-01-01

    Thermal decomposition of configurationally pure 1, 2-diarylpropenylcopper compounds Z-Vi{2}CU{4}Br{2} and Z-Vi{2}Cu{4}R{2} [Vi @? (2-Me{2}NC{6}H{4})C@?C(Me)-(C{6}H{4}Me-4), R @? 2-Me{2}NC{6}H{4} or 4-MeC{6}H{4}C@?C] predominantly results in the formation of ViH. In contrast, only dimers (ViVi) were

  2. Studies on the effect of pH on the sorption of cadmium (ll), nickel (II ...

    African Journals Online (AJOL)

    Studies on the effect of pH on the sorption of cadmium (ll), nickel (II), lead (II) and chromium (VI) from aqueous solutions by African white star apple ( Chrysophyllum albidium ) shell. ... The cleaning of our environment should be carried out with the use of natural products instead of chemicals so as to reduce pollution.

  3. Complexometric Determination of Zinc (II) in Pharmaceutical Samples Using Hydroxytriazenes

    OpenAIRE

    Khanam R.; Sharma J.C.; Khan S; Dashora R.; Chauhan R.S.; Goswami A. K.

    2010-01-01

    The present paper describes complexometric determination of Zn (II) using three hydroxytriazenes as metallochromic indicators in three medicines- Zivinal-CD, Becozine, and Vi - Syneral-Z. The hydroxytriazenes used were 3-hydroxy-3-phenyl-1-p-carboxyphenyltriazene (HPpCPT), 3-hydroxy-3-phenyl-1-o-chlorophenyltriazene (HPoCPT), 3-hydroxy-3-p-tolyl-1-p-sulphonamidophenyltriazene (HpTpSPT), respectively. Determination of zinc (II) was done by back titration method.

  4. As duas naturezas de Lévi-Strauss

    Directory of Open Access Journals (Sweden)

    Philippe Descola

    2011-11-01

    Full Text Available Aborda-se aqui a complexidade do status do par conceitual natureza e cultura no pensamento de Lévi-Strauss. Ao mesmo tempo ferramenta de análise, cena filosófica dos primórdios e antinomia a superar, revisita-se os diferentes usos e significados na obra de Lévi-Strauss do conceito de natureza e sua relação com o de cultura. Mostra-se como é possível reconhecer na obra de Lévi-Strauss dois conceitos de natureza: por um lado, uma natureza que se opõe à cultura num programa científico formulado em termos classicamente dualistas e, por outro, uma teoria do conhecimento decididamente monista que considera o espírito como parte e produto desse mesmo mundo. Argumenta-se que se o dualismo entre cultura e natureza fundou o pensamento estruturalista de Lévi-Strauss, é na própria obra deste que encontramos os argumentos e meios de superá-lo. A vocação do estruturalismo na antropologia de hoje, no entanto, é de ir mais longe neste caminho do que foi o próprio fundador.

  5. Anesthetic Challenges in an Adult with Mucopolysaccharidosis Type VI.

    Science.gov (United States)

    Cade, Jacqueline; Jansen, Nicholas

    2014-06-15

    The mucopolysaccharidoses are a group of lysosomal storage diseases with many skeletal and airway features that pose a challenge to anesthetists. We present the anesthetic management of a woman with mucopolysaccharidosis type VI undergoing cervical spine surgery and review the perioperative issues that may arise with this disease.

  6. Resúmenes Presentaciones de Pósteres VI ECAP

    OpenAIRE

    Vargas Arana, Editor Gabriel

    2016-01-01

    En este artículo se pueden encontrar los resúmenes de las presentaciones de pósteres del VI Encuentro Científico de la Amazonía Peruana, desarrollado el 27 y 28 de octubre de 2016 en la ciudad de Iquitos, Perú.

  7. Mechanism for partial oxidation of Cyclohexene by Chromium (VI ...

    African Journals Online (AJOL)

    The oxidation of cyclohexene by chromium (VI) oxide in aqueous and acetic media has been studied. The reaction products were analysed using classical method, IR and GC/MS analyses. The major products of the oxidation reaction in acetic acid medium are cyclohexanol, cyclohexanone, cyclohex-2-en-1-one, ...

  8. Removal of Cr(VI) from groundwater by Fe(0)

    Science.gov (United States)

    Gao, Yanjiao; Liu, Rui

    2017-11-01

    This research was conducted to investigate the treatment of hexavalent chromium (Cr(VI)) by iron powder (Fe(0)) columns of simulated permeable reactive barriers with and without calcium carbonate (CaCO3). Two columns filled with Fe(0) were used as Cr(VI) removal equipment running at a flow velocity of 10 ml/min at room temperature. After 200 days running of the two columns, the results showed that Fe(0) was an effective material for Cr(VI) reduction with an average removal rate of above 84.6%. The performance of Column 2 with CaCO3 was better than Column 1 without CaCO3 in terms of average Cr(VI) removal rate. The presence of CaCO3 buffered the increasing pH caused by Fe(0) corrosion in Column 2 and enhanced the removal rate of Column 2. Scanning Electron Microscopy (SEM) images of Fe(0) in the three stages of running of the two columns illustrated that the coat layer of Column 1 was a little thicker than that of Column 2. Energy-dispersive spectrometry (EDS) results showed that the surface of Fe(0) of Column 2 contained more chromium elements. Raman spectroscopy found that all iron oxide was generated on the Fe(0) surface of Column 1 and Column 2 and chromium class objects were only detected on Fe(0) surface in Column 2.

  9. Vi har beskæftigelseskrise, ikke uddannelseskrise

    DEFF Research Database (Denmark)

    Grindsted, Thomas Skou; Skou Grindsted, Louise

    2014-01-01

    Universiteterne er for dårlige, og kandidaternes kompetencer er forkerte, derfor ender mange i arbejdsløshed, mener Danmarks Akkrediteringsinstitution, Produktivitetskommissionen og DI. Men for få år siden var der mangel på højtuddannet arbejdskraft, så måske har vi et beskæftigelsesproblem snarere...

  10. Revolutsioonilisest ja igavikulisest VI Tallinna arhitektuuritriennaalil / Ave Randviir

    Index Scriptorium Estoniae

    Randviir, Ave, 1981-

    2005-01-01

    Tallinna arhitektuuritriennaali idee sünnist. 1990.a. toimus esimene triennaal nimega Põhja- ja Baltimaade Arhitektuuritriennaal. Niguliste kirikus toimunud VI Tallinna arhitektuuritriennaalist. Korraldajaks Irina Raud. Tunnuslauseks "Feeling Architecture". Triennaali avanud ja lõpetanud Peter Davey ja teiste esinejate ettekannetest. Eestlastest esinesid Juhan Maiste ja Vilen Künnapu

  11. Biosorption of hexavalent chromium (chromium (VI) ion from ...

    African Journals Online (AJOL)

    taye

    2015-04-01

    Apr 1, 2015 ... An experimental effluent analysis was conducted in conjunction with bioremediation process from ... Hexavalent Chromium (Cr (VI) is a by-product released .... Agriculture waste either saw dust or rice husk was procured from. Sabon Gari market, Zaria, Nigeria and brought to the Laboratory for analysis.

  12. Upper Limits on O VI Emission from Voyager Observations

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    The data processing is described in Murthy et al. (1999) and resulted in 426 obser- vations of the ... We detect no O VI emission in any of 426 UVS observations of the diffuse radiation field but do set upper limits on such ... Assuming that the emitting gas has a solar abundance of helium atoms and that the hydrogen and ...

  13. Finite difference simulation of biological chromium (VI) reduction in ...

    African Journals Online (AJOL)

    2013-05-08

    May 8, 2013 ... precipitates of reduced chromium produce toxic sludge that may be difficult to remediate (Gonzalez et al., 2003; Blowes, 2002). Recent studies have shown the possibility of using locally isolated organisms to treat Cr(VI) contaminated groundwater and/or soil. The treatment can be implemented ex situ ...

  14. Individual and Group Extension Methods: Perspectives from Vi ...

    African Journals Online (AJOL)

    A study was conducted to assess the effectiveness of group and individual extension methods in delivering agroforestry technologies at Vi-Agroforestry project, Masaka district. Participatory Rural Appraisals (PRAs) tools including semi-structured questionnaires were administrated to 90 randomly selected farmers who had ...

  15. Upper Limits on O VI Emission from Voyager Observations

    Indian Academy of Sciences (India)

    We have examined 426 Voyager fields distributed across the sky for O VI ( 1032/1038 Å) emission from the Galactic diffuse interstellar medium. No such emission was detected in any of our observed fields. Our most constraining limit was a 90% confidence upper limit of 2600 photons cm-2 sr-1 s-1 on the doublet ...

  16. Evaluation of Cr (VI) remediation potential of Eichornia sp in ...

    African Journals Online (AJOL)

    Purpose: Evaluation of Cr (VI) removal by indigenous chromium resistant bacterial strains alone and in combination with Eichornia sp. Methods: Three chromium resistant bacterial strains S-4 Ochrobactrum grignonense, SF-5 Bacillus sp. and S-6 Ochrobactrum pseudogrignonenses were isolated from industrial effluent.

  17. Osteogenesis Imperfecta Type VI in Individuals from Northern Canada.

    Science.gov (United States)

    Ward, Leanne; Bardai, Ghalib; Moffatt, Pierre; Al-Jallad, Hadil; Trejo, Pamela; Glorieux, Francis H; Rauch, Frank

    2016-06-01

    Osteogenesis imperfecta (OI) type VI is a recessively inherited form of OI that is caused by mutations in SERPINF1, the gene coding for pigment-epithelium derived factor (PEDF). Here, we report on two apparently unrelated children with OI type VI who had the same unusual homozygous variant in intron 6 of SERPINF1 (c.787-10C>G). This variant created a novel splice site that led to the in-frame addition of three amino acids to PEDF (p.Lys262_Ile263insLeuSerGln). Western blotting showed that skin fibroblasts with this mutation produced PEDF but failed to secrete it. Both children were treated with intravenous bisphosphonates, but the treatment of Individual 1 was switched to subcutaneous injections of denosumab (dose 1 mg per kg body weight, repeated every 3 months). An iliac bone sample obtained after 5 denosumab injections (and 3 months after the last injection) showed no change in the increased osteoid parameters that are typical of OI type VI, but the number of osteoclasts in trabecular bone was markedly increased. This suggests that the effect of denosumab on osteoclast suppression is of shorter duration in children with OI type VI than what has previously been reported on adults with osteoporosis.

  18. Selective removal of chromium (VI) from sulphates and other metal ...

    African Journals Online (AJOL)

    2011-10-06

    Oct 6, 2011 ... (Leonberg, Germany) equipped with a Lambda 1010 UV-Vis absorbance detector was ... AG 7 (4 x 50 mm) guard column and Dionex IonPac® AS7 (4 x. 250 mm) analytical ...... and equilibrium characterization of uranium(VI) adsorption onto .... netic nanoparticles in a polyvinylpyridine matrix. Polymer 41.

  19. Chromium(III) -- chromium(VI) interconversions in seawater

    NARCIS (Netherlands)

    Weijden, C.H. van der; Reith, M.

    1982-01-01

    The stable form of dissolved chromium in oxygenated seawater is Cr(VI). But Cr(III)-species are also present at an analytically significant level. It is shown that Cr(III) is oxidized only slowly by dissolved oxygen, and that manganese oxide is a strong catalyst for such oxidation. However, the low

  20. Leveraging Information Technology. Track VI: Hardware/Software Strategies.

    Science.gov (United States)

    CAUSE, Boulder, CO.

    Seven papers from the 1987 CAUSE conference's Track VI, Hardware/Software Strategies, are presented. They include: "Integrated Systems--The Next Steps" (Morris A. Hicks); "Administrative Microcomputing--Roads Traveled, Lessons Learned" (David L. Smallen); "Murphy's First Law and Its Application to Administrative…

  1. Paisaje del viñedo: patrimonio y recurso

    Directory of Open Access Journals (Sweden)

    Luis Vicente Elías

    2008-01-01

    Full Text Available La propuesta de que el paisaje del viñedo sea el complemento a la visita a la bodega, siendo esta el eje del turismo del vino, es el objetivo de este trabajo. Repasando los conceptos variables de patrimonio, llegamos al paisaje del viñedo como recurso, formando parte del patrimonio natural. Pero este no se puede desvincular de los otros aspectos patrimoniales, por lo que la cultura tradicional es el soporte de la tipología de paisaje que queremos proponer y que va contrastar con los nuevos paisajes del viñedo que surgen de las recientes técnicas en los cultivos y de la actual vitivicultura, emparejada con una moderna “cultura del vino”. El análisis de las diversas normativas, que salvaguardan el paisaje y la comprobación del escaso valor legal del paisaje del viñedo, es otro puntal de este trabajo que trata de unir paisaje con cultura tradicional como recursos del Turismo del Vino, integrados en las Rutas del Vino.

  2. Selective removal of chromium (VI) from sulphates and other metal ...

    African Journals Online (AJOL)

    Leaching of the chromate template from the polymer particles was achieved with successive stirring of the ion-imprinted polymer (IIP) particles in 4 M HNO3 solutions to obtain leached materials, which were then used for selective rebinding of Cr (VI) ions from aqueous solutions. Similarly, the non-imprinted polymer/control ...

  3. ViPiA: A Project for European Entrepreneurship

    Science.gov (United States)

    Folinas, Dimitris; Manthou, Vicky; Vlachopoulou, Maro

    2006-01-01

    The Virtual Pre-Incubator Accelerator (ViPiA) is a two-year project funded by the European Commission. The main goal of the programme is to create a training package for would-be entrepreneurs to assist them in developing their new venture concepts to a level at which they become attractive to potential investors. This paper describes and…

  4. AM(VI) partitioning studies. FY14 final report

    Energy Technology Data Exchange (ETDEWEB)

    Mincher, Bruce J. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-10-01

    The use of higher oxidation states of americium in partitioning from the lanthanides is under continued investigation by the sigma team. This is based on the hypothesis that Am(VI) can be produced and remain stable in irradiated first cycle raffinate solution long enough to perform solvent extraction for separations. The stability of Am(VI) to autoreduction was measured using millimolar americium concentrations in a 1-cm cell with a Cary 6000 UV/Vis spectrophotometer for data acquisition. At millimolar americium concentrations, Am(VI) is stable enough against its own autoreduction for separations purposes. A second major accomplishment during FY14 was the hot test. Americium oxidation and extraction was performed using a centrifugal contactor-based test bed consisting of an extraction stage and two stripping stages. Sixty-three percent americium extraction was obtained in one extraction stage, in agreement with batch contacts. Promising electrochemical oxidation results have also been obtained, using terpyridine ligand derivatized electrodes for binding of Am(III). Approximately 50 % of the Am(III) was oxidized to Am(V) over the course of 1 hour. It is believed that this is the first demonstration of the electrolytic oxidation of americium in a non-complexing solution. Finally, an initial investigation of Am(VI) extraction using diethylhexylbutyramide (DEHBA) was performed.

  5. 1990 Clean Air Act Amendment Summary: Title VI

    Science.gov (United States)

    This page provides an overview of the 1990 amendments to Title VI of the Clean Air Act, which were enacted to curb acid rain, urban air pollution and toxic air emissions. The edits to this title deal with stratospheric ozone and global climate protection.

  6. Adsorption kinetics for the removal of chromium (VI) from aqueous ...

    African Journals Online (AJOL)

    A comparison of kinetic models applied to the adsorption of Cr(VI) ions on the adsorbents was evaluated for the pseudo first-order, the pseudo second-order, Elovich and intraparticle diffusion kinetic models, respectively. Results show that the pseudo second-order kinetic model was found to correlate the experimental data ...

  7. mechanism for partial oxidation of cyclohexene by chromium (vi)

    African Journals Online (AJOL)

    DJFLEX

    The oxidation of cyclohexene by chromium (VI) oxide in aqueous and acetic media has been studied. The reaction products were analysed using classical method, IR and GC/MS analyses. The major products of the oxidation reaction in acetic acid medium are cyclohexanol, cyclohexanone, cyclohex-2-en-1-one, ...

  8. Molecular Interactions of Plutonium(VI) with Synthetic Manganese-Substituted Goethite

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Yung-Jin; Schwaiger, Luna Kestrel; Booth, Corwin H.; Kukkadapu, Ravi K.; Cristiano, Elena; Kaplan, Daniel; Nitsche, Heino

    2010-03-09

    Plutonium(VI) sorption on the surface of well-characterized synthetic manganese-substituted goethite minerals (Fe1-xMnxOOH) was studied using X-ray absorption spectroscopy. We chose to study the influence of manganese as a minor component in goethite, because goethite rarely exists as a pure phase in nature. Manganese X-ray absorption near-edge structure measurements indicated that essentially all the Mn in the goethite existed as Mn(III), even though Mn was added during mineral synthesis as Mn(II). Importantly, energy dispersive X-ray analysis demonstrated that Mn did not exist as discrete phases and that it was homogeneously mixed into the goethite to within the limit of detection of the method. Furthermore, Mössbauer spectra demonstrated that all Fe existed as Fe(III), with no Fe(II) present. Plutonium(VI) sorption experiments were conducted open to air and no attempt was made to exclude carbonate. The use of X-ray absorption spectroscopy allows us to directly and unambiguously measure the oxidation state of plutonium in situ at the mineral surface. Plutonium X-ray absorption near-edge structure measurements carried out on these samples showed that Pu(VI) was reduced to Pu(IV) upon contact with the mineral. This reduction appears to be strongly correlated with mineral solution pH, coinciding with pH transitions across the point of zero charge of the mineral. Furthermore, extended X-ray absorption fine structure measurements show evidence of direct plutonium binding to the metal surface as an inner-sphere complex. This combination of extensive mineral characterization and advanced spectroscopy suggests that sorption of the plutonium onto the surface of the mineral was followed by reduction of the plutonium at the surface of the mineral to form an inner-sphere complex. Because manganese is often found in the environment as a minor component associated with major mineral components, such as goethite, understanding the molecular-level interactions of plutonium with

  9. Chromium(VI)-resistant yeast isolated from a sewage treatment plant receiving tannery wastes.

    Science.gov (United States)

    Baldi, F; Vaughan, A M; Olson, G J

    1990-01-01

    A Cr(VI)-resistant yeast, designated strain DBVPG 6502, was isolated from a sewage treatment plant receiving wastes from tannery industries in Italy. The strain was tentatively identified as a species of Candida based on morphological and physiological analyses. This strain was highly resistant to Cr(VI) when compared with eight other yeast species, growing at Cr(VI) concentrations of up to 500 micrograms/ml (10 mM). This resistance was constitutive. The Cr(VI)-resistant yeast did not reduce Cr(VI) to Cr(III) species under aerobic conditions. The yeast showed very little accumulation of Cr(VI). Consequently, the mechanism of resistance of the yeast to Cr(VI) appears to involve reduced accumulation of Cr, as has been shown in Cr(VI)-resistant bacteria. Images PMID:2339879

  10. Cr(VI) generation during sample preparation of solid samples – A ...

    African Journals Online (AJOL)

    2009-05-15

    ) extraction should be to quantitatively extract Cr(VI), without inducing changes in speciation, i.e.. Cr(III)/Cr(VI) inter-conversions (Pettine and Capri, 2005). The reviews by Ashley et al. (2003), Broadhurst and Maizda.

  11. A phase I/II trial of intraoperative breast radiotherapy in an Asian population: 5-year results of local control and cosmetic outcome.

    Science.gov (United States)

    Kawamura, Mariko; Itoh, Yoshiyuki; Sawaki, Masataka; Kikumori, Toyone; Tsunoda, Nobuyuki; Kamomae, Takeshi; Kubota, Seiji; Okada, Tohru; Nakahara, Rie; Ito, Junji; Hayashi, Hironori; Naganawa, Shinji

    2015-07-25

    To date, there are no reports of intraoperative radiotherapy (IORT) use with long-term follow up as a method of accelerated partial breast irradiation (APBI) in Asian countries. We initiated a prospective phase I/II clinical trial of IORT in Japan in 2007, and herein, we report the 5-year follow-up results. The following inclusion criteria were used for enrollment in the trial: (1) tumor size surgery, (3) age >50 years, and (4) negative margins after resection. In February 2009, the eligibility criteria were changed to include only patients with sentinel lymph node-negative disease. In phase I, the radiotherapy dose was escalated from 19 Gy/fr to 21 Gy/fr, incremented by 1 Gy per step, with 3 patients in each step. Doses were escalated after all patients in the preceding cohort had completed treatment and exhibited only grade 1 or 2 toxicities at a given dose level. The recommended phase II dose was set at 21 Gy at 90 % isodose. The primary endpoint was early toxicity. Secondary endpoints were long-term efficacy and late toxicity. In addition, Hypertrophic scarring was evaluated retrospectively as a cosmetic outcome by a radiation oncologist. Between December 2007 and March 2010, 32 women with breast cancer were enrolled in the trial. The median age was 65 years (51-80 years), and the median follow-up time was 6 years. No recurrence or metastasis was observed in any patient. Grade 2 fibrosis was detected in 3 patients as an acute adverse event and in 2 patients as a late adverse event. Ten patients developed a hypertrophic scar 1 year after the IORT; the number of patients decreased to 7 in the 3 years of follow-up. The first group of female Asian patients tolerated the treatment with IORT in this Phase I/II study and remained recurrence-free for more than 5 years after treatment. However, 24 % of the patients developed hypertrophic scarring, an event that is being further examined in our ongoing multi-center Phase II trial of IORT for early breast cancer.

  12. Simulated solarlight catalytic reduction of Cr(VI) on microwave–ultrasonication synthesized flower-like CuO in the presence of tartaric acid

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Zhihui [College of Science, Nanjing Agricultural University, Nanjing 210095 (China); Yu, Yaqun; Fang, Di; Liang, Jianru [College of Resources and Environmental Science, Nanjing Agricultural University, Nanjing 210095 (China); Zhou, Lixiang, E-mail: lxzhou@njau.edu.cn [College of Resources and Environmental Science, Nanjing Agricultural University, Nanjing 210095 (China)

    2016-03-01

    In this study, flower-like CuO was successfully synthesized by a microwave–ultrasound assisted method and well characterized by X-ray diffractions, Fourier transform infrared spectrum, scanning electron microscopy, transmission electron microscopy, specific surface area, UV–vis diffused reflection spectra, X-ray photoelectron spectroscopy and point of zero charge. The photocatalytic performance of the as-prepared CuO was examined on the Cr(VI) reduction in the presence of tartaric acid under simulated solarlight irradiation. The results show that the developed CuO catalyst exhibited good photocatalytic activity with 100% reduction of Cr(VI) after irradiation of 30 min under the test condition of c(Cr(VI)) = 100 μM, catalyst loading = 400 mg/L, c(tartaric acid) = 4 mM and initial pH = 3. The reaction mechanism was proposed. The effects of test parameters, such as catalyst loading, tartaric acid concentration and initial pH, on Cr(VI) reduction efficiency were also investigated. It is worth mentioning that the developed catalyst can work at a relatively wide range of pH with quite high catalytic performance. - Highlights: • Flower-like CuO microstructure was prepared by MW-US assisted method. • The prepared CuO can catalyze the reduction Cr(VI) by tartaric acid under simulated solarlight. • The formation of ≡Cu(II)-tartaric acid complex play a key role in the reduction of Cr(VI). • The catalyst can operate effectively at a relatively wide range of pH.

  13. Cr(VI) reduction and Cr(III) immobilization by resting cells of Pseudomonas aeruginosa CCTCC AB93066: spectroscopic, microscopic, and mass balance analysis.

    Science.gov (United States)

    Kang, Chunxi; Wu, Pingxiao; Li, Liping; Yu, Langfeng; Ruan, Bo; Gong, Beini; Zhu, Nengwu

    2017-02-01

    The aim of this study was to investigate the mechanism of Cr(VI) reduction and Cr(III) immobilization by resting cells of Pseudomonas aeruginosa using batch experiments and analysis techniques. Data showed that resting cells of this strain (3.2 g/L dry weight) reduced 10 mg/L of Cr(VI) by 86% in Tris-HCl buffer solution under optimized conditions of 5 g/L of sodium acetate as an electron donor, pH of 7.0 and temperature of 37 °C within 24 h. Cr(VI) was largely converted to nontoxic Cr(III), and both soluble crude cell-free extracts and membrane-associated fractions were responsible for Cr(VI) reduction. While remnant Cr(VI) existed only in the supernatant, the content of resultant Cr(III) in supernatant, on cell surface and inside cells was 2.62, 1.06, and 5.07 mg/L, respectively, which was an indicative of extracellular and intracellular reduction of chromate. Scanning electron microscopy analysis combined with energy dispersive X-ray spectroscopy revealed the adsorption of chromium on the bacterial surface. Interaction between Cr(III) and cell surface functional groups immobilized Cr(III) as indicated by Fourier transform infrared analyses and X-ray photoelectron spectroscopy. Transmission electron microscopy revealed Cr(III) precipitates in bacterial interior suggesting that Cr(II) could also be intracellularly accumulated. Thus, it can be concluded that interior and exterior surfaces of resting P. aeruginosa cells were sites for reduction and immobilization of Cr(VI) and Cr(III), respectively. This is further insight into the underlying mechanisms of microbial chromate reduction.

  14. Rates of Cr(VI) Generation from CrxFe1-x(OH)3Solids upon Reaction with Manganese Oxide.

    Science.gov (United States)

    Pan, Chao; Liu, Huan; Catalano, Jeffrey G; Qian, Ao; Wang, Zimeng; Giammar, Daniel E

    2017-11-07

    The reaction of manganese oxides with Cr(III)-bearing solids in soils and sediments can lead to the natural production of Cr(VI) in groundwater. Building on previous knowledge of MnO 2 as an oxidant for Cr(III)-containing solids, this study systematically evaluated the rates and mechanisms of the oxidation of Cr(III) in iron oxides by δ-MnO 2 . The Fe/Cr ratio (x = 0.055-0.23 in Cr x Fe 1-x (OH) 3 ) and pH (5-9) greatly influenced the Cr(VI) production rates by controlling the solubility of Cr(III) in iron oxides. We established a quantitative relationship between Cr(VI) production rates and Cr(III) solubility of Cr x Fe 1-x (OH) 3 , which can help predict Cr(VI) production rates at different conditions. The adsorption of Cr(VI) and Mn(II) on solids shows a typical pH dependence for anions and cations. A multichamber reactor was used to assess the role of solid-solid contact in Cr x Fe 1-x (OH) 3 -MnO 2 interactions, which eliminates the contact of the two solids while still allowing aqueous species transport across a permeable membrane. Cr(VI) production rates were much lower in multichamber than in completely mixed batch experiments, indicating that the redox interaction is accelerated by mixing of the solids. Our results suggest that soluble Cr(III) released from Cr x Fe 1-x (OH) 3 solids to aqueous solution can migrate to MnO 2 surfaces where it is oxidized.

  15. Co-culture of chondrons and mesenchymal stromal cells reduces the loss of collagen VI and improves extracellular matrix production.

    Science.gov (United States)

    Owida, H A; De Las Heras Ruiz, T; Dhillon, A; Yang, Y; Kuiper, N J

    2017-12-01

    Adult articular chondrocytes are surrounded by a pericellular matrix (PCM) to form a chondron. The PCM is rich in hyaluronan, proteoglycans, and collagen II, and it is the exclusive location of collagen VI in articular cartilage. Collagen VI anchors the chondrocyte to the PCM. It has been suggested that co-culture of chondrons with mesenchymal stromal cells (MSCs) might enhance extracellular matrix (ECM) production. This co-culture study investigates whether MSCs help to preserve the PCM and increase ECM production. Primary bovine chondrons or chondrocytes or rat MSCs were cultured alone to establish a baseline level for ECM production. A xenogeneic co-culture monolayer model using rat MSCs (20, 50, and 80%) was established. PCM maintenance and ECM production were assessed by biochemical assays, immunofluorescence, and histological staining. Co-culture of MSCs with chondrons enhanced ECM matrix production, as compared to chondrocyte or chondron only cultures. The ratio 50:50 co-culture of MSCs and chondrons resulted in the highest increase in GAG production (18.5 ± 0.54 pg/cell at day 1 and 11 ± 0.38 pg/cell at day 7 in 50:50 co-culture versus 16.8 ± 0.61 pg/cell at day 1 and 10 ± 0.45 pg/cell at day 7 in chondron monoculture). The co-culture of MSCs with chondrons appeared to decelerate the loss of the PCM as determined by collagen VI expression, whilst the expression of high-temperature requirement serine protease A1 (HtrA1) demonstrated an inverse relationship to that of the collagen VI. Together, this implies that MSCs directly or indirectly inhibited HtrA1 activity and the co-culture of MSCs with chondrons enhanced ECM synthesis and the preservation of the PCM.

  16. Interaction of aerobic soil bacteria with plutonium(VI)

    Energy Technology Data Exchange (ETDEWEB)

    Panak, P.J. [Lawrence Berkeley National Lab., Berkeley, CA (United States). Chemical Sciences Div.; Nitsche, H. [Lawrence Berkeley National Lab., Berkeley, CA (United States). Chemical Sciences Div.; California Univ., Berkeley, CA (United States). Dept. of Chemistry

    2001-07-01

    We studied the interaction of Pu(VI) with Pseudomonas stutzeri ATCC 17588 and Bacillus sphaericus ATCC 14577, representatives of the main aerobic groups of soil bacteria present in the upper soil layers. The biosorption studies have shown that these soil bacteria accumulate high amounts of Pu(VI). The relative sorption efficiency toward Pu(VI) related to the amount of biomass used decreased with increasing biomass concentration due to increased agglomeration of the bacteria resulting in a decrease of the number of available complexing groups. Spores of Bacillus sphaericus showed a higher biosorption than the vegetative cells at low biomass concentration which decreased significantly with increasing biomass concentration. At higher biomass concentrations (> 0.7 g/L), the vegetative cells of both strains and the spores of B. sphaericus showed comparable sorption efficiencies. Investigations on the pH dependency of the biosorption and extraction studies with 0.01 M EDTA solution have shown that the biosorption of plutonium is a reversible process and the plutonium is bound by surface complexation. Optical absorption spectroscopy showed that one third of the initially present Pu(VI) was reduced to Pu(V) after 24 hours. Kinetic studies and solvent extraction to separate different oxidation states of Pu after contact with the biomass provided further information on the yield and the kinetics of the bacteria-mediated reduction. Long-term studies showed that also 16% of Pu(IV) was formed after one month. The slow kinetics of this process indicate that under our experimental conditions the Pu(IV) was not a produced by microbial reduction but seemed to be rather the result of the disproportionation of the formed Pu(V) or autoreduction of Pu(VI). (orig.)

  17. Influence of U(VI) on the metabolism of plant cells studied by microcalorimetry and TRLFS

    Energy Technology Data Exchange (ETDEWEB)

    Sachs, Susanne; Geipel, Gerhard [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Biogeochemistry; Fahmy, Karim; Oertel, Jana [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Biophysics; Bok, Frank [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Surface Processes

    2017-06-01

    Uranium(VI) shows a concentration-dependent influence on the metabolic activity of plant cells. With increasing U(VI) concentration, the predominant U(VI) species in medium R{sub red} changes from UO{sub 2}HPO{sub 4}(s) to (UO{sub 2}){sub 3}(OH){sub 5}{sup +}, which may affect the bioavailability of U(VI).

  18. Screening for autistic spectrum disorder in children aged 14-15 months. II: population screening with the Early Screening of Autistic Traits Questionnaire (ESAT). Design and general findings.

    NARCIS (Netherlands)

    Dietz, C.; Swinkels, S.H.N.; Daalen, E. van; Engeland, H. van; Buitelaar, J.K.

    2006-01-01

    A two-stage protocol for screening for autistic spectrum disorders (ASD) was evaluated in a random population of 31,724 children aged 14-15 months. Children were first pre-screened by physicians at well-baby clinics using a 4-item screening instrument. Infants that screened positive were then

  19. Efficient removal of Cr(III)-organic complexes from water using UV/Fe(III) system: Negligible Cr(VI) accumulation and mechanism.

    Science.gov (United States)

    Ye, Yuxuan; Jiang, Zhao; Xu, Zhe; Zhang, Xiaolin; Wang, Dandan; Lv, Lu; Pan, Bingcai

    2017-12-01

    Most available processes are incapable of removing Cr(III)-organic complexes from water due to their high solubility, extremely slow decomplexation rate, and possible formation of more toxic Cr(VI) during oxidation. Herein, we proposed a new combined process, i.e., UV/Fe(III) followed by alkaline precipitation (namely UV/Fe(III)+OH), to achieve highly efficient and environmentally benign removal of Cr(III)-organic complexes from water. The combined process could remove Cr(III)-citrate from 10.4 mg Cr/L to 0.36 mg Cr/L and ∼60% total organic carbon as well. More attractively, negligible Cr(VI) (Fe(III) generates ·OH radicals to transform Cr(III) into Cr(VI) and simultaneously released the citrate ligand to form Fe(III)-citrate simultaneously. Then, the photolysis of Fe(III)-citrate under UV irradiation involved the citrate degradation and the production of massive Fe(II) species, which in turn transformed the formed Cr(VI) back to Cr(III). The free metal ions, including Cr(III), Fe(II) and Fe(III) were removed by the subsequent alkaline precipitation. Also, the combined process is applicable to other Cr(III) complexes with EDTA, tartrate, oxalate, acetate. The applicability of the combined process was further demonstrated by treating two real tanning effluents, resulting in the residual Cr(III) below 1.5 mg/L (the discharge standard of China) and negligible formation of Cr(VI) (<0.004 mg/L) as well. In general, the combined process has a great potential for efficient removal of Cr(III) complexes from contaminated waters. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Laser-ignited frontal polymerization of shape-controllable poly(VI-co-AM) hydrogels based on 3D templates toward adsorption of heavy metal ions

    Science.gov (United States)

    Fan, Suzhen; Liu, Sisi; Wang, Xiao-Qiao; Wang, Cai-Feng; Chen, Su

    2016-06-01

    Given the increasing heavy metal pollution issue, fast preparation of polymeric hydrogels with excellent adsorption property toward heavy metal ions is very attractive. In this work, a series of poly( N-vinylimidazole-co-acrylamide) (poly(VI-co-AM)) hydrogels were synthesized via laser-ignited frontal polymerization (LIFP) for the first time. The dependence of frontal velocity and temperature on two factors monomer ratios and initiator concentrations was systematically investigated. Poly(VI-co-AM) hydrogels with any self-supporting shapes can be synthesized by a one-step LIFP in seconds through the application of 3D templates. These shape-persistent hydrogels are pH-responsive and exhibit excellent adsorption/desorption characteristics toward Mn(II), Zn(II), Cd(II), Ni(II), Cu(II) and Co(II) ions, and the adsorption conformed to the pseudo-second-order kinetic model. The reusability of the hydrogels toward mental ions adsorption was further researched, which suggested that the hydrogels can be reused without serious decrease in adsorption capacity. This work might open a promising strategy to facilely prepare shape-controllable hydrogels and expand the application of LIFP.

  1. The effect of temperature on the speciation of U(VI) in sulfate solutions

    Energy Technology Data Exchange (ETDEWEB)

    Rao, Linfeng; Tian, Guoxin

    2008-09-15

    Sulfate, one of the inorganic constituents that could be present in the nuclear waste repository, forms complexes with U(VI) and affects its migration in the environment. Results show that the complexation of U(VI) with sulfate is enhanced by the increase in temperature. The effect of temperature on the complexation and speciation of U(VI) in sulfate solutions is discussed.

  2. Investigations on photoelectrocatalytic reduction of Cr(VI) over titanium dioxide anode and metal cathode

    Energy Technology Data Exchange (ETDEWEB)

    Song, Han; Shang, Jing, E-mail: shangjing@pku.edu.cn; Ye, Junhui; Li, Qian

    2014-01-31

    Photocatalytic and photoelectrocatalytic (PEC) reductions of Cr(VI) based on TiO{sub 2} thin films were investigated under various conditions. Photogenerated electrons transferred from TiO{sub 2} thin film to cathode can contribute to PEC reduction of Cr(VI) only when the Fermi level of cathode lies above the chemical potential of Cr(VI), almost independent on the applied voltage of the direct current. In addition, the TiO{sub 2}-coated anode is the major site that accommodates the PEC reduction of Cr(VI) with hole scavenger citric acid, regardless of the Fermi level of the cathode. Although electron transfer from TiO{sub 2} to Cr(VI) is an exothermic process, the photogenerated holes in TiO{sub 2} can markedly hamper Cr(VI) reduction over the TiO{sub 2} thin film by oxidizing the lower-valence Cr back to Cr(VI), which may be counteracted by the citric acid. This research provides some in-depth insights on developing photocatalysts which enable highly efficient PEC reduction of Cr(VI) in the future. - Highlights: • Cr(VI) reduction on TiO{sub 2} photoanode is dominant with the addition of citric acid. • Cr(VI) is reduced on photocathode with Fermi level above Cr(VI) chemical potential. • Photogenerated holes can hamper Cr(VI) photoreduction over TiO{sub 2}.

  3. 76 FR 62148 - Title VI; Proposed Circular, Environmental Justice; Proposed Circular

    Science.gov (United States)

    2011-10-06

    ... Federal Transit Administration Title VI; Proposed Circular, Environmental Justice; Proposed Circular... information sessions, as published in the September 29, 2011, Federal Register Notices titled ``Title VI... sessions, as published in the September 29, 2011, Federal Register Notices titled ``Title VI; Proposed...

  4. Annexin VI is attached to transverse-tubule membranes in isolated skeletal muscle triads.

    Science.gov (United States)

    Barrientos, G; Hidalgo, C

    2002-07-15

    Annexin VI is a 68-kDa protein of the Annexin family, a group of Ca2+-dependent phospholipid-binding proteins widely distributed in mammalian tissues including skeletal muscle. We investigated a) which membrane system contributes Annexin VI to skeletal muscle triads, and b) whether Annexin VI removal affects triad integrity or function. Annexin VI was present in isolated triads and transverse tubules but not in heavy sarcoplasmic reticulum vesicles, indicating that Annexin VI binds to either free or triad-attached transverse tubules. Extraction with EGTA of Annexin VI from triads did not alter their migration as a single band in sucrose density gradients or their ouabain binding-site density, indicating that triad integrity does not require Annexin VI. Caffeine-induced Ca2+ release kinetics and Ca2+ uptake rates were likewise not affected by Annexin VI removal from triads, suggesting that Annexin VI is not involved in these functions. Annexin VI purified from rabbit skeletal muscle displayed Ca2+-dependent binding to liposomes containing phosphatidylinositol 4,5-bisphosphate and phosphatidylcholine. Binding saturated at 1/20 molar ratio phosphatidylinositol 4,5-bisphosphate/phosphatidylcholine and was optimal at free [Ca2+] > or = 20 mM. Extraction of Annexin VI from triads did not affect the generation of phosphatidylinositol 4-phosphate, phosphatidylinositol 4,5-bisphosphate, or phosphatidic acid by endogenous lipid kinases, suggesting that despite its capacity to bind to negatively charged phospholipids, Annexin VI does not affect the kinase activities responsible for their generation.

  5. Deferoxamine pretreatment prevents Cr(VI)-induced nephrotoxicity and oxidant stress: role of Cr(VI) chelation.

    Science.gov (United States)

    Molina-Jijón, Eduardo; Zarco-Márquez, Guillermo; Medina-Campos, Omar Noel; Zataraín-Barrón, Zyanya Lucía; Hernández-Pando, Rogelio; Pinzón, Enrique; Zavaleta, Rosa Marina; Tapia, Edilia; Pedraza-Chaverri, José

    2012-01-27

    Deferoxamine (DFO) is a recognized iron chelator which has been shown to exert nephroprotection in models of toxic nephropathies. In the present work the potential protective effects of DFO against Cr(VI)-induced nephrotoxicity and oxidant stress were evaluated. Rats were injected with a single injection (15mg/kg, s.c.) of potassium dichromate (K(2)Cr(2)O(7)). DFO was given as a single i.p. injection 30min before K(2)Cr(2)O(7) administration at three different doses (100, 200 and 400mg/kg). It was found that DFO pretreatment attenuated, in a dose-dependent way, K(2)Cr(2)O(7)-induced renal dysfunction and structural alterations evaluated by serum creatinine, blood urea nitrogen, creatinine clearance, proteinuria, plasma glutathione peroxidase activity, urinary excretion of N-acetyl-β-d-glucosaminidase and histological analyses. Furthermore, DFO prevented the K(2)Cr(2)O(7)-induced renal oxidant stress and the decrease in the activity of the antioxidant enzymes superoxide dismutase, glutathione reductase, glutathione peroxidase, glutathione-S-transferase and catalase. Finally it was found that DFO, at 400mg/kg, decreases renal Cr(VI) content which prompted us to evaluate the potential Cr(VI) chelating properties of this compound. Indeed was found in an in vitro assay that DFO was an effective Cr(VI) chelator with an IC(50) of 800μg. In additional groups of rats was found that DFO posttreatment was ineffective to attenuate K(2)Cr(2)O(7)-induced nephrotoxicity and renal oxidant stress. Furthermore, DFO was unable to modify urinary excretion of total chromium. The nephroprotective effect of DFO against Cr(VI)-induced nephrotoxicity and oxidant stress may be explained, at least partially, by the ability of DFO to chelate Cr(VI) and to attenuate renal Cr(VI) content. However, it cannot be excluded that the ability of DFO to chelate iron may also be involved in the protection observed in our study. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  6. Octarellin VI: using rosetta to design a putative artificial (β/α8 protein.

    Directory of Open Access Journals (Sweden)

    Maximiliano Figueroa

    Full Text Available The computational protein design protocol Rosetta has been applied successfully to a wide variety of protein engineering problems. Here the aim was to test its ability to design de novo a protein adopting the TIM-barrel fold, whose formation requires about twice as many residues as in the largest proteins successfully designed de novo to date. The designed protein, Octarellin VI, contains 216 residues. Its amino acid composition is similar to that of natural TIM-barrel proteins. When produced and purified, it showed a far-UV circular dichroism spectrum characteristic of folded proteins, with α-helical and β-sheet secondary structure. Its stable tertiary structure was confirmed by both tryptophan fluorescence and circular dichroism in the near UV. It proved heat stable up to 70°C. Dynamic light scattering experiments revealed a unique population of particles averaging 4 nm in diameter, in good agreement with our model. Although these data suggest the successful creation of an artificial α/β protein of more than 200 amino acids, Octarellin VI shows an apparent noncooperative chemical unfolding and low solubility.

  7. Effect of uranium (VI) on two sulphate-reducing bacteria cultures from a uranium mine site

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Monica [Centro de Ciencias do Mar, Faculdade de Ciencias e Tecnologia, DQF, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Faleiro, Maria Leonor [IBB-Centro de Biomedicina Molecular e Estrutural, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Chaves, Sandra; Tenreiro, Rogerio [Universidade de Lisboa, Faculdade de Ciencias, Centro de Biodiversidade, Genomica Integrativa e Funcional (BioFIG), Campus de FCUL, Campo Grande 1749-016 Lisboa (Portugal); Costa, Maria Clara, E-mail: mcorada@ualg.pt [Centro de Ciencias do Mar, Faculdade de Ciencias e Tecnologia, DQF, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal)

    2010-05-15

    This work was conducted to assess the impact of uranium (VI) on sulphate-reducing bacteria (SRB) communities obtained from environmental samples collected on the Portuguese uranium mining area of Urgeirica. Culture U was obtained from a sediment, while culture W was obtained from sludge from the wetland of that mine. Temperature gradient gel electrophoresis (TGGE) was used to monitor community changes under uranium stress conditions. TGGE profiles of dsrB gene fragment demonstrated that the initial cultures were composed of SRB species affiliated with Desulfovibrio desulfuricans, Desulfovibrio vulgaris and Desulfomicrobium spp. (sample U), and by species related to D. desulfuricans (sample W). A drastic change in SRB communities was observed as a result of uranium (VI) exposure. Surprisingly, SRB were not detected in the uranium removal communities. Such findings emphasize the need of monitoring the dominant populations during bio-removal studies. TGGE and phylogenetic analysis of the 16S rRNA gene fragment revealed that the uranium removal consortia are composed by strains affiliated to Clostridium genus, Caulobacteraceae and Rhodocyclaceae families. Therefore, these communities can be attractive candidates for environmental biotechnological applications associated to uranium removal.

  8. (II) complexes

    African Journals Online (AJOL)

    activities of Schiff base tin (II) complexes. Neelofar1 ... Conclusion: All synthesized Schiff bases and their Tin (II) complexes showed high antimicrobial and ...... Singh HL. Synthesis and characterization of tin (II) complexes of fluorinated Schiff bases derived from amino acids. Spectrochim Acta Part A: Molec Biomolec.

  9. Screening for Autistic Spectrum Disorder in Children Aged 14-15 Months. II: Population Screening with the Early Screening of Autistic Traits Questionnaire (ESAT). Design and General Findings

    Science.gov (United States)

    Dietz, Claudine; Swinkels, Sophie; van Daalen, Emma; van Engeland, Herman; Buitelaar, Jan K.

    2006-01-01

    A two-stage protocol for screening for autistic spectrum disorders (ASD) was evaluated in a random population of 31,724 children aged 14-15 months. Children were first pre-screened by physicians at well-baby clinics using a 4-item screening instrument. Infants that screened positive were then evaluated during a 1.5-h home visit by a trained…

  10. ["Epistemic Negotiations" and the Pluralism of the Radiation Protection Regime: The Determination of Radiation Protection Standards for the General Population in the Early Years After World War II].

    Science.gov (United States)

    Higuchi, Toshihiro

    2015-10-01

    Radiation protection standards for the general population have constituted one of the most controversial subjects in the history of atomic energy uses. This paper reexamines the process in which the first such standards evolved in the early postwar period. While the existing literature has emphasized a "collusion" between the standard-setters and users, the paper seeks to examine the horizontal relationship among the standard-setters. It first examines a series of expert consultations between the United States and the United Kingdom. Representing a different configuration of power and interest, the two failed to agree on the assessment of genetic damage and cancer induction whose occurrence might have no threshold and therefore be dependent on the population size. This stalemate prevented the International Commission on Radiological Protection (ICRP), established in 1950, from formulating separate guidelines for the general public. Situations radically changed when the Bikini incident in 1954 led to the creation of more scientific panels. One such panel under the U.S. Academy of Sciences enabled the geneticists to bridge their internal divide, unanimously naming 100 mSv as the genetically permissible dose for the general population. Not to be outdone, ICRP publicized its own guidelines for the same purpose. The case examined in this paper shows that the standard-setting process is best understood as a series of "epistemic negotiations" among and within the standard-setters, whose agendas were determined from the outset but whose outcomes were not.

  11. High-accuracy imputation for HLA class I and II genes based on high-resolution SNP data of population-specific references.

    Science.gov (United States)

    Khor, S-S; Yang, W; Kawashima, M; Kamitsuji, S; Zheng, X; Nishida, N; Sawai, H; Toyoda, H; Miyagawa, T; Honda, M; Kamatani, N; Tokunaga, K

    2015-12-01

    Statistical imputation of classical human leukocyte antigen (HLA) alleles is becoming an indispensable tool for fine-mappings of disease association signals from case-control genome-wide association studies. However, most currently available HLA imputation tools are based on European reference populations and are not suitable for direct application to non-European populations. Among the HLA imputation tools, The HIBAG R package is a flexible HLA imputation tool that is equipped with a wide range of population-based classifiers; moreover, HIBAG R enables individual researchers to build custom classifiers. Here, two data sets, each comprising data from healthy Japanese individuals of difference sample sizes, were used to build custom classifiers. HLA imputation accuracy in five HLA classes (HLA-A, HLA-B, HLA-DRB1, HLA-DQB1 and HLA-DPB1) increased from the 82.5-98.8% obtained with the original HIBAG references to 95.2-99.5% with our custom classifiers. A call threshold (CT) of 0.4 is recommended for our Japanese classifiers; in contrast, HIBAG references recommend a CT of 0.5. Finally, our classifiers could be used to identify the risk haplotypes for Japanese narcolepsy with cataplexy, HLA-DRB1*15:01 and HLA-DQB1*06:02, with 100% and 99.7% accuracy, respectively; therefore, these classifiers can be used to supplement the current lack of HLA genotyping data in widely available genome-wide association study data sets.

  12. Immunization with the conjugate vaccine Vi-CRM₁₉₇ against Salmonella typhi induces Vi-specific mucosal and systemic immune responses in mice.

    Science.gov (United States)

    Fiorino, Fabio; Ciabattini, Annalisa; Rondini, Simona; Pozzi, Gianni; Martin, Laura B; Medaglini, Donata

    2012-09-21

    Typhoid fever is a public health problem, especially among young children in developing countries. To address this need, a glycoconjugate vaccine Vi-CRM₁₉₇, composed of the polysaccharide antigen Vi covalently conjugated to the non-toxic mutant of diphtheria toxin CRM₁₉₇, is under development. Here, we assessed the antibody and cellular responses, both local and systemic, following subcutaneous injection of Vi-CRM₁₉₇. The glycoconjugate elicited Vi-specific serum IgG titers significantly higher than unconjugated Vi, with prevalence of IgG1 that persisted for at least 60 days after immunization. Vi-specific IgG, but not IgA, were present in intestinal washes. Lymphocytes proliferation after restimulation with Vi-CRM₁₉₇ was observed in spleen and mesenteric lymph nodes. These data confirm the immunogenicity of Vi-CRM₁₉₇ and demonstrate that the vaccine-specific antibody and cellular immune responses are present also in the intestinal tract, thus strengthening the suitability of Vi-CRM₁₉₇ as a promising candidate vaccine against Salmonella Typhi. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Four-year incidence and progression of visual impairment in a South Indian population with diabetes

    Directory of Open Access Journals (Sweden)

    Sangeetha Srinivasan

    2017-01-01

    Full Text Available Purpose: The aim of this study is to investigate the 4-year incidence and progression of visual impairment (VI and the associated risk factors for incident VI in a South Indian population with type 2 diabetes. Methods: A total of 634 participants with type 2 diabetes were found eligible after 4 years. Visual acuity (VA was estimated using the modified Early Treatment Diabetic Retinopathy Study protocol. VA in the better eye was considered for the assessment of VI based on the World Health Organization criteria. Mild VI was defined as VA 4.0 (odds ratio [OR]: 2.612 [1.148–5.942], P = 0.022 and lower socioeconomic score (OR: 0.965 [95% confidence interval, (0.933-0.998], P = 0.040 were associated with the risk of future incident VI. Refractive error (47% and cataract (30% were identified as the leading causes of incident VI at follow-up. Conclusions: VI seems to be a significant problem among diabetic participants in the South Indian population. Refractive error and cataract are the leading but treatable causes of incident VI in this population and would benefit from intervention.

  14. Polymer based nanocomposites for the removal of Cr(VI) from water

    CSIR Research Space (South Africa)

    Setshedi, K

    2012-10-10

    Full Text Available .3 pH 2 pH 6 % R em ov al pH Feasibility test for Cr(VI) contaminated ground water and the effect of competing ions 100 ppm Cr(VI) sol. Nanocomposite + Cr(VI) sol 0 ppm Cr(VI) sol. 0 20 40 60 80 100 Q e( m g/ g) Cr 6+ Cr 6... nanocomposites for the removal of Cr(VI) from water Emerging Researcher Symposium Katlego Setshedi 10 October 2012 Outline ? CSIR 2012 Slide 2 ? Background ? Problem statement ? Health impacts ? Remedies ? Objectives ? Experimental procedure...

  15. Non-clinical Safety and Efficacy of an AAV2/8 Vector Administered Intravenously for Treatment of Mucopolysaccharidosis Type VI

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    Rita Ferla

    2017-09-01

    Full Text Available In vivo gene therapy with adeno-associated viral (AAV vectors is safe and effective in humans. We recently demonstrated that AAV8-mediated liver gene transfer is effective in animal models of mucopolysaccharidosis type VI (MPS VI, a rare lysosomal storage disease that is caused by arylsulfatase B (ARSB deficiency. In preparing for a first-in-human trial, we performed non-clinical studies to assess the safety of intravenous administrations of AAV2/8.TBG.hARSB produced under good manufacturing practice-like conditions. No toxicity was observed in AAV-treated mice, except for a transient increase in alanine aminotransferase in females and thyroid epithelial hypertrophy. AAV2/8.TBG.hARSB biodistribution and expression confirmed the liver as the main site of both infection and transduction. Shedding and breeding studies suggest that the risk of both horizontal and germline transmission is minimal. An AAV dose-response study in MPS VI mice was performed to define the range of doses to be used in the clinical study. Overall, these data support the non-clinical safety and efficacy of AAV2/8.TBG.hARSB and pave the way for a phase I/II clinical trial based on intravascular infusions of AAV8 in patients with MPS VI.

  16. Zinc Metal-Organic Framework for Selective Detection and Differentiation of Fe(III) and Cr(VI) Ions in Aqueous Solution.

    Science.gov (United States)

    Lv, Rui; Li, Hui; Su, Jian; Fu, Xin; Yang, Boyi; Gu, Wen; Liu, Xin

    2017-10-16

    A new luminescent Zn(II)-based metal-organic framework (MOF), [Zn 2 (TPOM)(NDC) 2 ]·3.5H 2 O (Zn-MOF; TPOM = tetrakis(4-pyridyloxymethylene)methane and H 2 ndc = 2,6-naphthalenedicarboxylic acid), was successfully synthesized by a hydrothermal reaction. The MOF exhibits excellent luminescence emission, and it can detect Fe(III) and Cr(VI) ions with high selectivity, well antiinterference performance, and short response time. In addition, Zn-MOF was selected as a parent coordination compound to encapsulate Eu 3+ cations to obtain a Eu 3+ -incorporated sample (Eu 3+ @Zn-MOF). Subsequently, we explored the potential application of Eu 3+ @Zn-MOF as a probe for the selective sensing of Fe(III) and Cr(VI) ions, and it revealed that we could differentiate Fe(III) and Cr(VI) ions by the combination Zn-MOF and Eu 3+ @Zn-MOF. More importantly, it represents the first example of MOF-based luminescent sensors which can detect and differentiate Fe(III) and Cr(VI) ions selectively. And the possible sensing mechanism was discussed in detail.

  17. Food and water security issues in Russia II: Water security in general population of Russian Arctic, Siberia and Far East, 2000–2011

    Science.gov (United States)

    Dudarev, Alexey A.; Dushkina, Eugenia V.; Sladkova, Yuliya N.; Alloyarov, Pavel R.; Chupakhin, Valery S.; Dorofeyev, Vitaliy M.; Kolesnikova, Tatjana A.; Fridman, Kirill B.; Evengard, Birgitta; Nilsson, Lena M.

    2013-01-01

    Background Poor state of water supply systems, shortage of water purification facilities and disinfection systems, low quality of drinking water generally in Russia and particularly in the regions of the Russian Arctic, Siberia and Far East have been defined in the literature. However, no standard protocol of water security assessment has been used in the majority of studies. Study design and methods Uniform water security indicators collected from Russian official statistical sources for the period 2000–2011 were used for comparison for 18 selected regions in the Russian Arctic, Siberia and Far East. The following indicators of water security were analyzed: water consumption, chemical and biological contamination of water reservoirs of Categories I and II of water sources (centralized – underground and surface, and non-centralized) and of drinking water. Results Water consumption in selected regions fluctuated from 125 to 340 L/person/day. Centralized water sources (both underground and surface sources) are highly contaminated by chemicals (up to 40–80%) and biological agents (up to 55% in some regions), mainly due to surface water sources. Underground water sources show relatively low levels of biological contamination, while chemical contamination is high due to additional water contamination during water treatment and transportation in pipelines. Non-centralized water sources are highly contaminated (both chemically and biologically) in 32–90% of samples analyzed. Very high levels of chemical contamination of drinking water (up to 51%) were detected in many regions, mainly in the north-western part of the Russian Arctic. Biological contamination of drinking water was generally much lower (2.5–12%) everywhere except Evenki AO (27%), and general and thermotolerant coliform bacteria predominated in drinking water samples from all regions (up to 17.5 and 12.5%, correspondingly). The presence of other agents was much lower: Coliphages – 0.2–2

  18. Food and water security issues in Russia II: Water security in general population of Russian Arctic, Siberia and Far East, 2000–2011

    Directory of Open Access Journals (Sweden)

    Alexey A. Dudarev

    2013-12-01

    Full Text Available Background . Poor state of water supply systems, shortage of water purification facilities and disinfection systems, low quality of drinking water generally in Russia and particularly in the regions of the Russian Arctic, Siberia and Far East have been defined in the literature. However, no standard protocol of water security assessment has been used in the majority of studies. Study design and methods . Uniform water security indicators collected from Russian official statistical sources for the period 2000–2011 were used for comparison for 18 selected regions in the Russian Arctic, Siberia and Far East. The following indicators of water security were analyzed: water consumption, chemical and biological contamination of water reservoirs of Categories I and II of water sources (centralized – underground and surface, and non-centralized and of drinking water. Results . Water consumption in selected regions fluctuated from 125 to 340 L/person/day. Centralized water sources (both underground and surface sources are highly contaminated by chemicals (up to 40–80% and biological agents (up to 55% in some regions, mainly due to surface water sources. Underground water sources show relatively low levels of biological contamination, while chemical contamination is high due to additional water contamination during water treatment and transportation in pipelines. Non-centralized water sources are highly contaminated (both chemically and biologically in 32–90% of samples analyzed. Very high levels of chemical contamination of drinking water (up to 51% were detected in many regions, mainly in the north-western part of the Russian Arctic. Biological contamination of drinking water was generally much lower (2.5–12% everywhere except Evenki AO (27%, and general and thermotolerant coliform bacteria predominated in drinking water samples from all regions (up to 17.5 and 12.5%, correspondingly. The presence of other agents was much lower: Coliphages

  19. Food and water security issues in Russia II: water security in general population of Russian Arctic, Siberia and Far East, 2000-2011.

    Science.gov (United States)

    Dudarev, Alexey A; Dushkina, Eugenia V; Sladkova, Yuliya N; Alloyarov, Pavel R; Chupakhin, Valery S; Dorofeyev, Vitaliy M; Kolesnikova, Tatjana A; Fridman, Kirill B; Evengard, Birgitta; Nilsson, Lena M

    2013-01-01

    Poor state of water supply systems, shortage of water purification facilities and disinfection systems, low quality of drinking water generally in Russia and particularly in the regions of the Russian Arctic, Siberia and Far East have been defined in the literature. However, no standard protocol of water security assessment has been used in the majority of studies. Uniform water security indicators collected from Russian official statistical sources for the period 2000-2011 were used for comparison for 18 selected regions in the Russian Arctic, Siberia and Far East. The following indicators of water security were analyzed: water consumption, chemical and biological contamination of water reservoirs of Categories I and II of water sources (centralized--underground and surface, and non-centralized) and of drinking water. Water consumption in selected regions fluctuated from 125 to 340 L/person/day. Centralized water sources (both underground and surface sources) are highly contaminated by chemicals (up to 40-80%) and biological agents (up to 55% in some regions), mainly due to surface water sources. Underground water sources show relatively low levels of biological contamination, while chemical contamination is high due to additional water contamination during water treatment and transportation in pipelines. Non-centralized water sources are highly contaminated (both chemically and biologically) in 32-90% of samples analyzed. Very high levels of chemical contamination of drinking water (up to 51%) were detected in many regions, mainly in the north-western part of the Russian Arctic. Biological contamination of drinking water was generally much lower (2.5-12%) everywhere except Evenki AO (27%), and general and thermotolerant coliform bacteria predominated in drinking water samples from all regions (up to 17.5 and 12.5%, correspondingly). The presence of other agents was much lower: Coliphages--0.2-2.7%, Clostridia spores, Giardia cysts, pathogenic bacteria, Rotavirus

  20. Wrongful Actions of the German Armed Forces Against the Civilian Population of Germany in the Final Stages of World War II

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    Sergej I. Belov

    2014-06-01

    Full Text Available The aim of this study is to examine the issue of crimes against civilians committed by soldiers of the Wehrmacht and Waffen-SS in Germany in 1945. Disclosed the causes, background and nature of illegal actions by officers and soldiers against civilians. Discussed topic offenses by military command structures and the NSDAP. Studied the issue of representativeness eyewitness illegal actions of German soldiers. Introduced into science not previously involved researchers archival materials – reports, information bulletins and reports of political offices of the 1st Ukrainian and 2nd Belorussian Fronts on the mood of the population of the occupied territories and enemy troops for February – June 1945.