WorldWideScience

Sample records for systems vi population

  1. 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.

  2. Type VI secretion system.

    Science.gov (United States)

    Salomon, Dor; Orth, Kim

    2015-03-30

    Bacteria employ a variety of tools to survive in a competitive environment. Salomon and Orth describe one such tool-the Type 6 Secretion Systems used by bacteria to deliver a variety of toxins into competing cells. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Polarography of uranium(VI)-salicylic acid system

    International Nuclear Information System (INIS)

    Salah, El-Maraghy B.

    1980-01-01

    Uranium(VI)-salicylic acid system has been studied polarographically in perchloric acid medium. Varying concentrations of HClO 4 and salicylic acid have been used. The nature of the polarographic waves is irreversible. (author)

  4. The new geographic information system in ETVA VI.PE.

    Science.gov (United States)

    Xagoraris, Zafiris; Soulis, George

    2016-08-01

    ETVA VI.PE. S.A. is a member of the Piraeus Bank Group of Companies and its activities include designing, developing, exploiting and managing Industrial Areas throughout Greece. Inside ETVA VI.PE.'s thirty-one Industrial Parks there are currently 2,500 manufacturing companies established, with 40,000 employees and € 2.5 billion of invested funds. In each one of the industrial areas ETVA VI.PE guarantees the companies industrial lots of land (sites) with propitious building codes and complete infrastructure networks of water supply, sewerage, paved roads, power supply, communications, cleansing services, etc. The development of Geographical Information System for ETVA VI.PE.'s Industrial Parks started at the beginning of 1992 and consists of three subsystems: Cadastre, that manages the information for the land acquisition of Industrial Areas; Street Layout - Sites, that manages the sites sold to manufacturing companies; Networks, that manages the infrastructure networks (roads, water supply, sewerage etc). The mapping of each Industrial Park is made incorporating state-of-the-art photogrammetric, cartographic and surveying methods and techniques. Passing through the phases of initial design (hybrid GIS) and system upgrade (integrated Gis solution with spatial database), the system is currently operating on a new upgrade (integrated gIS solution with spatial database) that includes redesigning and merging the system's database schemas, along with the creation of central security policies, and the development of a new web GIS application for advanced data entry, highly customisable and standard reports, and dynamic interactive maps. The new GIS bring the company to advanced levels of productivity and introduce the new era for decision making and business management.

  5. Thermodynamic analysis of Mo(VI)-Fe(III)-S(VI)-H2O system for separation of molybdenum and iron

    Science.gov (United States)

    Xiao, Chao; Zeng, Li; Xiao, Liansheng; Zhang, Guiqing

    2017-11-01

    The separation of molybdenum and iron is one of key issues of the hydrometallurgical preparation of pure molybdenum chemical products. The thermodynamic equilibrium diagrams for distribution of species at different pH values and different concentrations of molybdenum, iron and sulfur with the systems of Mo(VI)-H2O, Fe(III)-S(VI)-H2O and Mo(VI)-Fe(III)-S(VI)-H2O at 298 K were established, separately. Thermodynamic analysis results revealed that both molybdenum and iron were transformed from their anions to cations with the decrease in pH values. The pHMf0.5 for the conversion of molybdenum anions to cations decreased from 0.92 to 0.20 with the increase in the molybdenum concentration from 0.05 mol/L to 1 mol/L (pHMf50 is defined as the pH value when target metal anions occupy 50% mole fraction of total). The total sulfur concentration has significant effect on the conversion of iron (III) species with the pH change. The separation of molybdenum (VI) and iron (III) from acidic solutions using a tertiary amine extractant N235 could be achieved by decreasing the total sulfur concentration and controlling the equilibrium pH in an optimum range. The verification test results showed that the operating window for the separation of Mo(VI) and Fe(III) from a solution containing 0.01 mol/L [Mo]T, 0.05 mol/L [Fe]T and 1.15 mol/L [S]T was in the pH range of 0.5-1.0, which was consistent with the thermodynamic analysis.

  6. 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.

  7. Type VI Secretion System Toxins Horizontally Shared between Marine Bacteria.

    Directory of Open Access Journals (Sweden)

    Dor Salomon

    2015-08-01

    Full Text Available The type VI secretion system (T6SS is a widespread protein secretion apparatus used by Gram-negative bacteria to deliver toxic effector proteins into adjacent bacterial or host cells. Here, we uncovered a role in interbacterial competition for the two T6SSs encoded by the marine pathogen Vibrio alginolyticus. Using comparative proteomics and genetics, we identified their effector repertoires. In addition to the previously described effector V12G01_02265, we identified three new effectors secreted by T6SS1, indicating that the T6SS1 secretes at least four antibacterial effectors, of which three are members of the MIX-effector class. We also showed that the T6SS2 secretes at least three antibacterial effectors. Our findings revealed that many MIX-effectors belonging to clan V are "orphan" effectors that neighbor mobile elements and are shared between marine bacteria via horizontal gene transfer. We demonstrated that a MIX V-effector from V. alginolyticus is a functional T6SS effector when ectopically expressed in another Vibrio species. We propose that mobile MIX V-effectors serve as an environmental reservoir of T6SS effectors that are shared and used to diversify antibacterial toxin repertoires in marine bacteria, resulting in enhanced competitive fitness.

  8. A simple Cr(VI)–S(IV)–O{sub 2} system for rapid and simultaneous reduction of Cr(VI) and oxidative degradation of organic pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Yanan; Yang, Shaojie [Department of Environmental Science, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resources and Environmental Science, Wuhan University, 430079 (China); Zhou, Danna, E-mail: zdncug@163.com [Faculty of Material Science and Chemistry, China University of Geosciences, Wuhan 430074 (China); Wu, Feng [Department of Environmental Science, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resources and Environmental Science, Wuhan University, 430079 (China)

    2016-04-15

    Highlights: • Rapid and simultaneous reduction of Cr(VI) and degradation of organic pollutants occur. • Oxysulfur radicals generated in Cr(VI)–S(IV)–O{sub 2} system oxidize the organic pollutants. • Acidic pH facilitates the reactions from both directions of reduction and oxidation. • Degradation potential of aromatic amines depends on the substituted groups. • Cr(VI)–S(IV)–O{sub 2} system is promising for “waste control by waste”. - Abstract: Hexavalent chromium (Cr(VI)), a heavy-metal contaminant, can be easily reduced to less toxic trivalent chromium (Cr(III)) by sulfite ions (S(IV)). However, S(IV) has not drawn as much attention as the ferrous ion has. We report herein a novel Cr(VI)–S(IV)–O{sub 2} system containing sulfite ions that rapidly and simultaneously reduces Cr(VI) and oxidize organic pollutants in the presence of oxygen in aqueous solutions. This Cr(VI)–S(IV)-O{sub 2} system contains the initiator Cr(VI), the reductant S(IV), and the oxidant O{sub 2}, which produce oxysulfur radicals (mainly SO{sub 4}·{sup −} and SO{sub 5}·{sup −}) and hydroxyl radicals (OH·). The Cr(VI)/S(IV) molar ratio, pH, and oxygen content play important roles in the entire reaction system. Acidic conditions (pH 3.0) facilitated degradation of organic compounds and reduction of Cr(VI) as well. In addition, experiments of rapid degradation of several kinds of organic pollutants such as azo dye (acid orange 7, AO7), aniline, phenol, bisphenol A etc were also conducted. Preliminary results show that the removal rates of the analogs of phenols or aromatic amines in this Cr(VI)–S(IV)–O{sub 2} system have a relationship with the electronic parameters (Hammett constant, σ) of the substituted groups. Thus, the Cr(VI)–S(IV)–O{sub 2} system, provides an excellent strategy of “waste control by waste” for removing multiple industrial contaminants.

  9. The effects of chromium(VI) on the thioredoxin system: Implications for redox regulation

    Science.gov (United States)

    Myers, Charles R.

    2014-01-01

    Hexavalent chromium [Cr(VI)] compounds are highly redox active and have long been recognized as potent cytotoxins and carcinogens. The intracellular reduction of Cr(VI) generates reactive Cr intermediates, which are themselves strong oxidants, as well as superoxide, hydrogen peroxide, and hydroxyl radical. These probably contribute to the oxidative damage and effects on redox-sensitive transcription factors that have been reported. However, the identification of events that initiate these signaling changes has been elusive. More recent studies show that Cr(VI) causes irreversible inhibition of thioredoxin reductase (TrxR) and oxidation of thioredoxin (Trx) and peroxiredoxin (Prx). Mitochondrial Trx2/Prx3 are more sensitive to Cr(VI) treatment than cytosolic Trx1/Prx1, although both compartments show thiol oxidation with higher doses or longer treatments. Thiol redox proteomics demonstrate that Trx2, Prx3, and Trx1 are among the most sensitive proteins in cells to Cr(VI) treatment. Their oxidation could therefore represent initiating events that have widespread implications for protein thiol redox control and for multiple aspects of redox signaling. This review summarizes the effects of Cr(VI) on the TrxR/Trx system and how these events could influence a number of downstream redox signaling systems that are influenced by Cr(VI) exposure. Some of the signaling events discussed include the activation of apoptosis signal regulating kinase and MAP kinases (p38 and JNK) and the modulation of a number of redox-sensitive transcription factors including AP-1, NF-κB, p53, and Nrf2. PMID:22542445

  10. Identification of a functional type VI secretion system in Campylobacter jejuni conferring capsule polysaccharide sensitive cytotoxicity

    NARCIS (Netherlands)

    Bleumink-Pluym, Nancy M C; van Alphen, Lieke B; Bouwman, Lieneke I; Wösten, MM; van Putten, Jos P M

    2013-01-01

    The pathogen Campylobacter jejuni is the principal cause of bacterial food-borne infections. The mechanism(s) that contribute to bacterial survival and disease are still poorly understood. In other bacterial species, type VI secretion systems (T6SS) are increasingly recognized to contribute to

  11. The ternary sorption system U(VI)-phosphate-silica explained by spectroscopy and thermodynamic modelling

    Energy Technology Data Exchange (ETDEWEB)

    Foerstendorf, Harald; Stockmann, Madlen; Heim, Karsten; Mueller, Katharina; Brendler, Vinzenz [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Surface Processes; Comarmond, M.J.; Payne, T.E. [Australian Nuclear Science and Technology Organisation, Lucas Heights (Australia); Steudtner, Robin [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Inst. of Resource Ecology

    2017-06-01

    Spectroscopic data of sorption processes potentially provide direct impact on Surface Complexation Modelling (SCM) approaches. Based on spectroscopic data of the ternary sorption system U(VI)/phosphate/silica strongly suggesting the formation of a precipitate as the predominant surface process, SCM calculations accurately reproduced results from classical batch experiments.

  12. The ternary sorption system U(VI)-phosphate-silica explained by spectroscopy and thermodynamic modelling

    International Nuclear Information System (INIS)

    Foerstendorf, Harald; Stockmann, Madlen; Heim, Karsten; Mueller, Katharina; Brendler, Vinzenz; Steudtner, Robin

    2017-01-01

    Spectroscopic data of sorption processes potentially provide direct impact on Surface Complexation Modelling (SCM) approaches. Based on spectroscopic data of the ternary sorption system U(VI)/phosphate/silica strongly suggesting the formation of a precipitate as the predominant surface process, SCM calculations accurately reproduced results from classical batch experiments.

  13. eBaViR, easy balance virtual rehabilitation system: a study with patients.

    Science.gov (United States)

    González-Fernández, M; Gil-Gómez, José-Antonio; Alcañiz, M; Noé, E; Colomer, C

    2010-01-01

    eBaViR is a virtual rehabilitation system, which has been developed for balance rehabilitation for patients suffering from acquired brain injury. It is a game-based system that uses a low-cost interface, the Nintendo Wii Balance Board. The games have been specifically designed with the help of experts in the rehabilitation of balance disorders and can be adapted to patients according to their needs. We present an experimental study that has been carried out using the system. The aim of the study is to determine whether this setup could be applied as a Virtual Rehabilitation System for balance rehabilitation in Acquired Brain Injury. We randomly divided patients into two groups: a trial group and a control group. The trial group used eBaViR system during the rehabilitation sessions, and the control group followed traditional rehabilitation sessions. We obtained encouraging results.

  14. Development of technical information processing system(VI)

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jee Hoh; Kim, Tae Hwan; Choi, Kwang; Chung, Hyun Sook; Keum, Jong Yong [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1994-12-01

    This project is to establish high-quality information circulation system by developing serials-control system to improve serials management from ordering to distributing and availability on R and D and to advance in quality of information service needed in R and D by fast retrieval and providing of research information with CD-Net. The results of the project are as follows. 1. Serials management process which covers from ordering to distributing have higher efficiency by development of subscription information system. 2. Systematic control on each issue of serials is achieved by development of serials checking system. 3. It is possible to provide vol. and no. information of issue received currently to researchers promptly by improvement of serials holding information system. 4. Retrieval of research information contained in various CD-ROM DB throughout KAERI-NET is possible by research on construction methods of CD-Net. 2 figs, 25 refs. (Author).

  15. Development of technical information processing system(VI)

    International Nuclear Information System (INIS)

    Lee, Jee Hoh; Kim, Tae Hwan; Choi, Kwang; Chung, Hyun Sook; Keum, Jong Yong

    1994-12-01

    This project is to establish high-quality information circulation system by developing serials-control system to improve serials management from ordering to distributing and availability on R and D and to advance in quality of information service needed in R and D by fast retrieval and providing of research information with CD-Net. The results of the project are as follows. 1. Serials management process which covers from ordering to distributing have higher efficiency by development of subscription information system. 2. Systematic control on each issue of serials is achieved by development of serials checking system. 3. It is possible to provide vol. and no. information of issue received currently to researchers promptly by improvement of serials holding information system. 4. Retrieval of research information contained in various CD-ROM DB throughout KAERI-NET is possible by research on construction methods of CD-Net. 2 figs, 25 refs. (Author)

  16. Investigation of the removal mechanism of Cr(VI) in groundwater using activated carbon and cast iron combined system.

    Science.gov (United States)

    Huang, Dandan; Wang, Guangcai; Li, Zhihong; Kang, Fei; Liu, Fei

    2017-08-01

    Zero-valent iron (Fe 0 ) has been widely used for Cr(VI) removal; however, the removal mechanisms of Cr(VI) from aqueous solution under complex hydrogeochemical conditions were poorly understood. In this research, the mixed materials containing cast iron and activated carbon were packed in columns for the treatment of aqueous Cr(VI)-Cr(III) in groundwater with high concentration of Ca 2+ , Mg 2+ , HCO 3 - , NO 3 - , and SO 4 2- . We investigate the influences of those ions on Cr(VI) removal, especially emphasizing on the reaction mechanisms and associated precipitations which may lead to porosity loss by using X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) techniques. The results show that the precipitations accumulated on the material surface were (Fe/Cr) (oxy)hydroxide, mixed Fe(III)-Cr(III) (oxy)hydroxides, Fe 2 O 3 , CaCO 3 , and MgCO 3 . During these reactions, the Cr(VI) was reduced to Cr(III) coupled with the oxidated Fe 0 to Fe(II) through the galvanic corrosion formed by the Fe 0 -C and/or the direct electron transfer between Fe 0 and Cr(VI). In addition, Cr(VI) could be reduced by aqueous Fe(II), which dominated the whole removal efficiency. The primary aqueous Cr(III) was completely removed together with Cr(III) reduced from Cr(VI) even when Cr(VI) was detected in the effluent, which meant that the aqueous Cr(III) could occupy the adsorption sites. In general, the combined system was useful for the Cr(VI)-Cr(III) treatment based on galvanic corrosion, and the hardness ions had a negative effect on Cr(VI) removal by forming the carbonates which might promote the passivation of materials and decrease the removal capacity of the system.

  17. Barbus meridionalis Risso, 1827 populations status in the Vişeu River basin (Maramureş Mountains Nature Park

    Directory of Open Access Journals (Sweden)

    Bănăduc Doru

    2017-06-01

    Full Text Available The ecological state of lotic ecosystems occupied naturally by Barbus meridionalis, in the Vişeu Basin within the Maramureş Mountains Natural Park, vary among good to reduced. The inventoried human activities which negatively influence the ecologic state of the Barbus meridionalis species habitats and populations are the organic and mining pollution, and poaching. The habitats with low and inadequate conditions created a reduced status of the Barbus meridionalis populations; the status of Barbus meridionalis populations is not so much affected in the cases of habitats of average to good condition. Barbus meridionalis is considered a relatively common fish species in the researched watershed despite the fact that its populations ecological status has decreased from 2007-2015, but the restoration potential in the area for improving this species status is high.

  18. Circumplex model of marital and family systems: VI. Theoretical update.

    Science.gov (United States)

    Olson, D H; Russell, C S; Sprenkle, D H

    1983-03-01

    This paper updates the theoretical work on the Circumplex Model and provides revised and new hypotheses. Similarities and contrasts to the Beavers Systems Model are made along with comments regarding Beavers and Voeller's critique. FACES II, a newly revised assessment tool, provides both "perceived" and "ideal" family assessment that is useful empirically and clinically.

  19. World Energy Data System (WENDS). Volume VI. International agreement profiles

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-06-01

    The World Energy Data System contains organized data on those countries and international organizations that may have critical impact on world energy. The international agreement profiles in WENDS are all energy-related and are organized by energy technology. These are: coal; conservation; fusion; geothermal; nuclear fission; oil, gas, and shale; solar, wind, and ocean thermal; and other (cooperation in electrical power equipment acquisition, energy, energy research, etc.). The agreement profiles are accessible by energy technology and alphabetically by country.

  20. The roles of polycarboxylates in Cr(VI)/sulfite reaction system: Involvement of reactive oxygen species and intramolecular electron transfer

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Bo, E-mail: bjiang86upc@163.com [State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Qingdao 266580, Shandong (China); School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033 (China); Wang, Xianli; Liu, Yukun [State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Qingdao 266580, Shandong (China); Wang, Zhaohui [College of Environmental Science and Engineering, Donghua University, Shanghai 201620 (China); Southern Cross GeoScience, Southern Cross University, Lismore, NSW 2480 (Australia); Zheng, Jingtang, E-mail: jtzheng03@163.com [State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Qingdao 266580, Shandong (China); Wu, Mingbo, E-mail: wumb@upc.edu.cn [State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Qingdao 266580, Shandong (China)

    2016-03-05

    Highlights: • The formations of SO{sub 4}·{sup −} and OH·, involve in Cr(VI) reduction induced by S(IV). • Affinity of polycarboxylate to Cr(VI) accelerates Cr(VI) reduction rate. • Polycarboxylates can act as electron donors for Cr(VI) reduction retrenching S(IV). • Only oxalate can enhance the formations of SO{sub 4}·{sup −} and OH· in Cr(VI)/S(IV) system. - Abstract: In this study, the effects of polycarboxylates on both Cr(VI) reduction and S(IV) consumption in Cr(VI)/S(IV) system was investigated in acidic solution. Under aerobic condition, the productions of reactive oxygen species (ROS), i.e., SO{sub 4}·{sup −} and OH·, have been confirmed in S(IV) reducing Cr(VI) process by using electron spin resonance and fluorescence spectrum techniques, leading to the excess consumption of S(IV). However, when polycarboxylates (oxalic, citric, malic and tartaric acid) were present in Cr(VI)/S(IV) system, the affinity of polycarboxylates to CrSO{sub 6}{sup 2−} can greatly promote the reduction of Cr(VI) via expanding the coordination of Cr(VI) species from tetrahedron to hexahedron. Besides, as alternatives to S(IV), these polycarboxylates can also act as electron donors for Cr(VI) reduction via intramolecular electron transfer reaction, which is dependent on the energies of the highest occupied molecular orbital of these polycarboxylates. Notably, the variant electron donating capacity of these polycarboxylates resulted in different yield of ROS and therefore the oxidation efficiencies of other pollutants, e.g., rhodamine B and As(III). Generally, this study does not only shed light on the mechanism of S(IV) reducing Cr(VI) process mediated by polycarboxylates, but also provides an escalated, cost-effective and green strategy for the remediation of Cr(VI) using sulfite as a reductant.

  1. Computing Effect Size Measures with ViSta-The Visual Statistics System

    Directory of Open Access Journals (Sweden)

    Nuria Cortada de Kohan

    2009-03-01

    Full Text Available Effect size measures are recognized as a necessary complement to statistical hypothesis testing because they provide important information that such tests alone cannot offer. In this paper we: a briefly review the importance of effect size measures, b describe some calculation algorithms for the case of the difference between two means, and c provide a new and easy-to-use computer program to perform these calculations within ViSta “The Visual Statistics System”. A worked example is also provided to illustrate some practical issues concerning the interpretation and limits of effect size computation. The audience for this paper includes novice researchers as well as ViSta’s user interested on applying effect size measures.

  2. Fat ViP MRI: Virtual Phantom Magnetic Resonance Imaging of water-fat systems.

    Science.gov (United States)

    Salvati, Roberto; Hitti, Eric; Bellanger, Jean-Jacques; Saint-Jalmes, Hervé; Gambarota, Giulio

    2016-06-01

    Virtual Phantom Magnetic Resonance Imaging (ViP MRI) is a method to generate reference signals on MR images, using external radiofrequency (RF) signals. The aim of this study was to assess the feasibility of ViP MRI to generate complex-data images of phantoms mimicking water-fat systems. Various numerical phantoms with a given fat fraction, T2* and field map were designed. The k-space of numerical phantoms was converted into RF signals to generate virtual phantoms. MRI experiments were performed at 4.7T using a multi-gradient-echo sequence on virtual and physical phantoms. The data acquisition of virtual and physical phantoms was simultaneous. Decomposition of the water and fat signals was performed using a complex-based water-fat separation algorithm. Overall, a good agreement was observed between the fat fraction, T2* and phase map values of the virtual and numerical phantoms. In particular, fat fractions of 10.5±0.1 (vs 10% of the numerical phantom), 20.3±0.1 (vs 20%) and 30.4±0.1 (vs 30%) were obtained in virtual phantoms. The ViP MRI method allows for generating imaging phantoms that i) mimic water-fat systems and ii) can be analyzed with water-fat separation algorithms based on complex data. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. ViSlang: A system for interpreted domain-specific languages for scientific visualization

    KAUST Repository

    Rautek, Peter

    2014-12-31

    Researchers from many domains use scientific visualization in their daily practice. Existing implementations of algorithms usually come with a graphical user interface (high-level interface), or as software library or source code (low-level interface). In this paper we present a system that integrates domain-specific languages (DSLs) and facilitates the creation of new DSLs. DSLs provide an effective interface for domain scientists avoiding the difficulties involved with low-level interfaces and at the same time offering more flexibility than high-level interfaces. We describe the design and implementation of ViSlang, an interpreted language specifically tailored for scientific visualization. A major contribution of our design is the extensibility of the ViSlang language. Novel DSLs that are tailored to the problems of the domain can be created and integrated into ViSlang. We show that our approach can be added to existing user interfaces to increase the flexibility for expert users on demand, but at the same time does not interfere with the user experience of novice users. To demonstrate the flexibility of our approach we present new DSLs for volume processing, querying and visualization. We report the implementation effort for new DSLs and compare our approach with Matlab and Python implementations in terms of run-time performance.

  4. Enhanced Cr(VI) removal from groundwater by Fe0-H2O system with bio-amended iron corrosion

    DEFF Research Database (Denmark)

    Yin, Weizhao; Li, Yongtao; Wu, Jinhua

    2017-01-01

    transfer on the solid phase. The results also showed that the reduction of Cr(VI) by microorganisms was insignificant, indicating the adsorption/co-precipitation of Cr by iron oxides on iron surface was responsible for the overall Cr(VI) removal. Our study demonstrated that the bio-amended iron corrosion......Abstract A one-pot bio-iron system was established to investigate synergetic abiotic and biotic effects between iron and microorganisms on Cr(VI) removal. More diverse iron corrosion and reactive solids, such as green rusts, lepidocrocite and magnetite were found in the bio-iron system than...... in the Fe0-H2O system, leading to 4.3 times higher Cr(VI) removal efficiency in the bio-iron system than in the Fe0-H2O system. The cycling experiment also showed that the Cr(VI) removal capacity of Fe0 in the bio-iron system was 12.4 times higher than that in the Fe0-H2O system. A 62 days of life...

  5. Genome-Wide Analysis of Type VI System Clusters and Effectors in Burkholderia Species

    Directory of Open Access Journals (Sweden)

    Thao Thi Nguyen

    2018-02-01

    Full Text Available Type VI secretion system (T6SS has been discovered in a variety of gram-negative bacteria as a versatile weapon to stimulate the killing of eukaryotic cells or prokaryotic competitors. Type VI secretion effectors (T6SEs are well known as key virulence factors for important pathogenic bacteria. In many Burkholderia species, T6SS has evolved as the most complicated secretion pathway with distinguished types to translocate diverse T6SEs, suggesting their essential roles in this genus. Here we attempted to detect and characterize T6SSs and potential T6SEs in target genomes of plant-associated and environmental Burkholderia species based on computational analyses. In total, 66 potential functional T6SS clusters were found in 30 target Burkholderia bacterial genomes, of which 33% possess three or four clusters. The core proteins in each cluster were specified and phylogenetic trees of three components (i.e., TssC, TssD, TssL were constructed to elucidate the relationship among the identified T6SS clusters. Next, we identified 322 potential T6SEs in the target genomes based on homology searches and explored the important domains conserved in effector candidates. In addition, using the screening approach based on the profile hidden Markov model (pHMM of T6SEs that possess markers for type VI effectors (MIX motif (MIX T6SEs, 57 revealed proteins that were not included in training datasets were recognized as novel MIX T6SE candidates from the Burkholderia species. This approach could be useful to identify potential T6SEs from other bacterial genomes.

  6. Development of automatic system for determination of U(IV), U(VI), Pu(III), Pu(IV), Pu(VI) and nitric acid in nuclear fuel reprocessing streams by spectrophotometry

    International Nuclear Information System (INIS)

    Kuno, Yusuke; Kawabe, Katsuya; Akiyama, Takao

    1991-01-01

    An automatic system for the determination of the stable oxidation states of uranium and plutonium, and nitric acid in nuclear fuel reprocessing streams has been developed. The system based on a spectrophotometry is capable of rapidly determining U(IV), U(VI), Pu(III), Pu(IV) and Pu(VI). The spectrum obtained from a mixed solution is separated into individual spectra of several components with graphical operations. Acidic concentration can also be obtained from the ratio of specific peaks in a spectrum of U(IV), U(VI), Pu(III) or Pu(IV). (author)

  7. Perancangan Safety Instrumented System pada Proses Loading PT Pertamina (Persero Refinery Unit VI Balongan

    Directory of Open Access Journals (Sweden)

    Rahmat Tri widodo

    2013-09-01

    Full Text Available Salah satu proses yang ada di PT Pertamina (Persero Refinery Unit VI adalah pengiriman crude oil menuju kapal tanker. Proses tersebut disebut dengan proses loading. Terdapat beberapa jenis crude yang dikirim pada proses loading tersebut, diantaranya adalah crude Jatibarang dan Crude DCO. Terdapat beberapa masalah yang kerap terjadi pada proses loading ini. Yang sering terjadi adalah kebocoran offshore pipeline yang biasa disebabkan oleh korosi air laut. Selain itu juga pernah terjadi penyumbatan pipa oleh crude akibat heater yang tidak berfungsi dengan baik. Sampai saat ini safety system yang ada pada proses loading ini hanya sebuah shutdown valve yang dijalankan manual dengan menggunakan hand switch. Sistem tersebut masih belum bisa menangani permasalahan yang ada. Oleh karena itu pada tugas akhir kali ini dilakukan perancangan SIS pada jalur loading PT Pertamina RU VI Balongan yang kemudian disimulasikan pada software Matlab (Simulink. Simulasi dilakukan dengan memberikan manipulasi besar disturbance yang merepresentasikan kebocoran pada offshore pipeline. Berdasarkan simulasi yang dilakukan, didapatkan bahwa SIS dapat berjalan dengan baik karena dapat menghentikan proses dengan menutup ESDV dan mematikan pompa saat keadaan perbedaan tekanan antara ujung-ujung pipa offshore tinggi. Tingginya perbedaan tekanan antar ujung offshore pipeline mengindikasikan terjadinya kebocoran. SIS yang sudah dirancang kemudian dihitung nilai PFDtotal dan diapatkan nilai sebesar 0,085 sehingga rancangan SIS.

  8. Study on chromium (VI) reduction kinetics by Pseudomonas aeruginosa using a combined system of acoustic wave impedance analyzer and UV-vis spectrophotometer.

    Science.gov (United States)

    Li, Xuefang; Wei, Wanzhi; Zeng, Xiandong; He, Deliang; Yin, Jian; Zeng, Jinxiang; Wu, Ling

    2006-09-01

    A novel system combining acoustic wave impedance (AWI) analyzer with UV-vis spectrophotometer was developed for the study of chromium (VI) reduction kinetics by Pseudomonas aeruginosa. AWI gave information about the growth of Pseudomonas aeruginosa, and UV-vis spectrophotometer gave information about the concentration of chromium (VI) simultaneously. A combined system response model, for chromium (VI) reduction kinetics at lower initial chromium (VI) concentrations, was derived and proved based on the novel system. Taking into account the effect of bacterial growth on chromium (VI) reduction, the new model successfully simulated chromium (VI) bioremediation process. By fitting chromium (VI) reduction data toward the derived model, the kinetic parameters related to the process were obtained. When the concentration of peptone was 10 g L(-1), the half-velocity reduction rate constant K (C) and the maximum specific chromium (VI) reduction rate constant nu(max) were 0.7682 mg chromium (VI) L(-1) and 2.5814 x 10(-12) mg chromium (VI) cells(-1) h(-1), respectively. It was found that the combined system can provide real-time, reliable, and two-dimensional kinetic information, and can be applied to study other biological processes.

  9. Modeling and Control of a Parallel Waste Heat Recovery System for Euro-VI Heavy-Duty Diesel Engines

    NARCIS (Netherlands)

    Feru, E.; Willems, F.P.T.; Jager, B. de; Steinbuch, M.

    2014-01-01

    This paper presents the modeling and control of a waste heat recovery system for a Euro-VI heavy-duty truck engine. The considered waste heat recovery system consists of two parallel evaporators with expander and pumps mechanically coupled to the engine crankshaft. Compared to previous work, the

  10. Rules of Engagement: The Type VI Secretion System in Vibrio cholerae.

    Science.gov (United States)

    Joshi, Avatar; Kostiuk, Benjamin; Rogers, Andrew; Teschler, Jennifer; Pukatzki, Stefan; Yildiz, Fitnat H

    2017-04-01

    Microbial species often exist in complex communities where they must avoid predation and compete for favorable niches. The type VI secretion system (T6SS) is a contact-dependent bacterial weapon that allows for direct killing of competitors through the translocation of proteinaceous toxins. Vibrio cholerae is a Gram-negative pathogen that can use its T6SS during antagonistic interactions with neighboring prokaryotic and eukaryotic competitors. The T6SS not only promotes V. cholerae's survival during its aquatic and host life cycles, but also influences its evolution by facilitating horizontal gene transfer. This review details the recent insights regarding the structure and function of the T6SS as well as the diverse signals and regulatory pathways that control its activation in V. cholerae. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. The Vibrio cholerae type VI secretion system employs diverse effector modules for intraspecific competition.

    Science.gov (United States)

    Unterweger, Daniel; Miyata, Sarah T; Bachmann, Verena; Brooks, Teresa M; Mullins, Travis; Kostiuk, Benjamin; Provenzano, Daniele; Pukatzki, Stefan

    2014-04-01

    Vibrio cholerae is a Gram-negative bacterial pathogen that consists of over 200 serogroups with differing pathogenic potential. Only strains that express the virulence factors cholera toxin (CT) and toxin-coregulated pilus (TCP) are capable of pandemic spread of cholera diarrhoea. Regardless, all V. cholerae strains sequenced to date harbour genes for the type VI secretion system (T6SS) that translocates effectors into neighbouring eukaryotic and prokaryotic cells. Here we report that the effectors encoded within these conserved gene clusters differ widely among V. cholerae strains, and that immunity proteins encoded immediately downstream from the effector genes protect their host from neighbouring bacteria producing corresponding effectors. As a consequence, strains with matching effector-immunity gene sets can coexist, while strains with different sets compete against each other. Thus, the V. cholerae T6SS contributes to the competitive behaviour of this species.

  12. Identification of a functional type VI secretion system in Campylobacter jejuni conferring capsule polysaccharide sensitive cytotoxicity.

    Directory of Open Access Journals (Sweden)

    Nancy M C Bleumink-Pluym

    Full Text Available The pathogen Campylobacter jejuni is the principal cause of bacterial food-borne infections. The mechanism(s that contribute to bacterial survival and disease are still poorly understood. In other bacterial species, type VI secretion systems (T6SS are increasingly recognized to contribute to bacterial pathogenesis by toxic effects on host cells or competing bacterial species. Here we report the presence of a functional Type VI secretion system in C. jejuni. Proteome and genetic analyses revealed that C. jejuni strain 108 contains a 17-kb T6SS gene cluster consisting of 13 T6SS-conserved genes, including the T6SS hallmark genes hcp and vgrG. The cluster lacks an ortholog of the ClpV ATPase considered important for T6SS function. The sequence and organization of the C. jejuni T6SS genes resemble those of the T6SS located on the HHGI1 pathogenicity island of Helicobacter hepaticus. The C. jejuni T6SS is integrated into the earlier acquired Campylobacter integrated element CJIE3 and is present in about 10% of C. jejuni isolates including several isolates derived from patients with the rare clinical feature of C. jejuni bacteremia. Targeted mutagenesis of C. jejuni T6SS genes revealed T6SS-dependent secretion of the Hcp needle protein into the culture supernatant. Infection assays provided evidence that the C. jejuni T6SS confers contact-dependent cytotoxicity towards red blood cells but not macrophages. This trait was observed only in a capsule-deficient bacterial phenotype. The unique C. jejuni T6SS phenotype of capsule-sensitive contact-mediated hemolysis represents a novel evolutionary pathway of T6SS in bacteria and expands the repertoire of virulence properties associated with T6SS.

  13. Identification of a functional type VI secretion system in Campylobacter jejuni conferring capsule polysaccharide sensitive cytotoxicity.

    Science.gov (United States)

    Bleumink-Pluym, Nancy M C; van Alphen, Lieke B; Bouwman, Lieneke I; Wösten, Marc M S M; van Putten, Jos P M

    2013-01-01

    The pathogen Campylobacter jejuni is the principal cause of bacterial food-borne infections. The mechanism(s) that contribute to bacterial survival and disease are still poorly understood. In other bacterial species, type VI secretion systems (T6SS) are increasingly recognized to contribute to bacterial pathogenesis by toxic effects on host cells or competing bacterial species. Here we report the presence of a functional Type VI secretion system in C. jejuni. Proteome and genetic analyses revealed that C. jejuni strain 108 contains a 17-kb T6SS gene cluster consisting of 13 T6SS-conserved genes, including the T6SS hallmark genes hcp and vgrG. The cluster lacks an ortholog of the ClpV ATPase considered important for T6SS function. The sequence and organization of the C. jejuni T6SS genes resemble those of the T6SS located on the HHGI1 pathogenicity island of Helicobacter hepaticus. The C. jejuni T6SS is integrated into the earlier acquired Campylobacter integrated element CJIE3 and is present in about 10% of C. jejuni isolates including several isolates derived from patients with the rare clinical feature of C. jejuni bacteremia. Targeted mutagenesis of C. jejuni T6SS genes revealed T6SS-dependent secretion of the Hcp needle protein into the culture supernatant. Infection assays provided evidence that the C. jejuni T6SS confers contact-dependent cytotoxicity towards red blood cells but not macrophages. This trait was observed only in a capsule-deficient bacterial phenotype. The unique C. jejuni T6SS phenotype of capsule-sensitive contact-mediated hemolysis represents a novel evolutionary pathway of T6SS in bacteria and expands the repertoire of virulence properties associated with T6SS.

  14. Constitutive type VI secretion system expression gives Vibrio cholerae intra- and interspecific competitive advantages.

    Directory of Open Access Journals (Sweden)

    Daniel Unterweger

    Full Text Available The type VI secretion system (T6SS mediates protein translocation across the cell membrane of Gram-negative bacteria, including Vibrio cholerae - the causative agent of cholera. All V. cholerae strains examined to date harbor gene clusters encoding a T6SS. Structural similarity and sequence homology between components of the T6SS and the T4 bacteriophage cell-puncturing device suggest that the T6SS functions as a contractile molecular syringe to inject effector molecules into prokaryotic and eukaryotic target cells. Regulation of the T6SS is critical. A subset of V. cholerae strains, including the clinical O37 serogroup strain V52, express T6SS constitutively. In contrast, pandemic strains impose tight control that can be genetically disrupted: mutations in the quorum sensing gene luxO and the newly described regulator gene tsrA lead to constitutive T6SS expression in the El Tor strain C6706. In this report, we examined environmental V. cholerae isolates from the Rio Grande with regard to T6SS regulation. Rough V. cholerae lacking O-antigen carried a nonsense mutation in the gene encoding the global T6SS regulator VasH and did not display virulent behavior towards Escherichia coli and other environmental bacteria. In contrast, smooth V. cholerae strains engaged constitutively in type VI-mediated secretion and displayed virulence towards prokaryotes (E. coli and other environmental bacteria and a eukaryote (the social amoeba Dictyostelium discoideum. Furthermore, smooth V. cholerae strains were able to outcompete each other in a T6SS-dependent manner. The work presented here suggests that constitutive T6SS expression provides V. cholerae with an advantage in intraspecific and interspecific competition.

  15. 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, |ΔG Cr |>|ΔG Cr-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.

  16. Effectiveness of a Wii balance board-based system (eBaViR for balance rehabilitation: a pilot randomized clinical trial in patients with acquired brain injury

    Directory of Open Access Journals (Sweden)

    Alcañiz Mariano

    2011-05-01

    results suggest that eBaViR represents a safe and effective alternative to traditional treatment to improve static balance in the ABI population. These results have encouraged us to reinforce the virtual treatment with new exercises, so an evolution of the system is currently being developed.

  17. Effectiveness of a Wii balance board-based system (eBaViR) for balance rehabilitation: a pilot randomized clinical trial in patients with acquired brain injury.

    Science.gov (United States)

    Gil-Gómez, José-Antonio; Lloréns, Roberto; Alcañiz, Mariano; Colomer, Carolina

    2011-05-23

    Acquired brain injury (ABI) is the main cause of death and disability among young adults. In most cases, survivors can experience balance instability, resulting in functional impairments that are associated with diminished health-related quality of life. Traditional rehabilitation therapy may be tedious. This can reduce motivation and adherence to the treatment and thus provide a limited benefit to patients with balance disorders. We present eBaViR (easy Balance Virtual Rehabilitation), a system based on the Nintendo® Wii Balance Board® (WBB), which has been designed by clinical therapists to improve standing balance in patients with ABI through motivational and adaptative exercises. We hypothesize that eBaViR, is feasible, safe and potentially effective in enhancing standing balance. In this contribution, we present a randomized and controlled single blinded study to assess the influence of a WBB-based virtual rehabilitation system on balance rehabilitation with ABI hemiparetic patients. This study describes the eBaViR system and evaluates its effectiveness considering 20 one-hour-sessions of virtual reality rehabilitation (n = 9) versus standard rehabilitation (n = 8). Effectiveness was evaluated by means of traditional static and dynamic balance scales. The final sample consisted of 11 men and 6 women. Mean ± SD age was 47.3 ± 17.8 and mean ± SD chronicity was 570.9 ± 313.2 days. Patients using eBaViR had a significant improvement in static balance (p = 0.011 in Berg Balance Scale and p = 0.011 in Anterior Reaches Test) compared to patients who underwent traditional therapy. Regarding dynamic balance, the results showed significant improvement over time in all these measures, but no significant group effect or group-by-time interaction was detected for any of them, which suggests that both groups improved in the same way. There were no serious adverse events during treatment in either group. The results suggest that eBaViR represents a safe and effective

  18. Bile Salts Modulate the Mucin-Activated Type VI Secretion System of Pandemic Vibrio cholerae.

    Directory of Open Access Journals (Sweden)

    Verena Bachmann

    Full Text Available The causative agent of cholera, Vibrio cholerae, regulates its diverse virulence factors to thrive in the human small intestine and environmental reservoirs. Among this pathogen's arsenal of virulence factors is the tightly regulated type VI secretion system (T6SS. This system acts as an inverted bacteriophage to inject toxins into competing bacteria and eukaryotic phagocytes. V. cholerae strains responsible for the current 7th pandemic activate their T6SS within the host. We established that T6SS-mediated competition occurs upon T6SS activation in the infant mouse, and that this system is functional under anaerobic conditions. When investigating the intestinal host factors mucins (a glycoprotein component of mucus and bile for potential regulatory roles in controlling the T6SS, we discovered that once mucins activate the T6SS, bile acids can further modulate T6SS activity. Microbiota modify bile acids to inhibit T6SS-mediated killing of commensal bacteria. This interplay is a novel interaction between commensal bacteria, host factors, and the V. cholerae T6SS, showing an active host role in infection.

  19. Highly efficient removal of chromium(VI) by Fe/Ni bimetallic nanoparticles in an ultrasound-assisted system.

    Science.gov (United States)

    Zhou, Xiaobin; Jing, Guohua; Lv, Bihong; Zhou, Zuoming; Zhu, Runliang

    2016-10-01

    Highly active Fe/Ni bimetallic nanocomposites were prepared by using the liquid-phase reduction method, and they were proven to be effective for Cr(VI) removal coupled with US irradiation. The US-assisted Fe/Ni bimetallic system could maintain a good performance for Cr(VI) removal at a wide pH range of 3-9. Based on the characterization of the Fe/Ni nanoparticles before and after reaction, the high efficiency of the mixed system could attribute to the synergistic effects of the catalysis of Ni(0) and US cavitation. Ni(0) could facilitate the Cr(VI) reduction through electron transfer and catalytic hydrogenation. Meanwhile, US could fluidize the Fe/Ni nanoparticles to increase the actual reactive surface area and clean off the co-precipitated Fe(III)-Cr(III) hydroxides to maintain the active sites on the surface of the Fe/Ni nanoparticles. Thus, compared with shaking, the US-assisted Fe/Ni system was more efficient on Cr(VI) removal, which achieved 94.7% removal efficiency of Cr(VI) within 10 min. The pseudo-first-order rate constant (kobs) in US-assisted Fe/Ni system (0.5075 min(-1)) was over 5 times higher than that under shaking (0.0972 min(-1)). Moreover, the Fe/Ni nanoparticles still have a good performance under US irradiation after 26 days aging as well as regeneration. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Type VI secretion system MIX-effectors carry both antibacterial and anti-eukaryotic activities.

    Science.gov (United States)

    Ray, Ann; Schwartz, Nika; de Souza Santos, Marcela; Zhang, Junmei; Orth, Kim; Salomon, Dor

    2017-11-01

    Most type VI secretion systems (T6SSs) described to date are protein delivery apparatuses that mediate bactericidal activities. Several T6SSs were also reported to mediate virulence activities, although only few anti-eukaryotic effectors have been described. Here, we identify three T6SSs in the marine bacterium Vibrio proteolyticus and show that T6SS1 mediates bactericidal activities under warm marine-like conditions. Using comparative proteomics, we find nine potential T6SS1 effectors, five of which belong to the polymorphic MIX-effector class. Remarkably, in addition to six predicted bactericidal effectors, the T6SS1 secretome includes three putative anti-eukaryotic effectors. One of these is a MIX-effector containing a cytotoxic necrotizing factor 1 domain. We demonstrate that T6SS1 can use this MIX-effector to target phagocytic cells, resulting in morphological changes and actin cytoskeleton rearrangements. In conclusion, the V. proteolyticus T6SS1, a system homologous to one found in pathogenic vibrios, uses a suite of polymorphic effectors that target both bacteria and eukaryotic neighbors. © 2017 The Authors. Published under the terms of the CC BY 4.0 license.

  1. Crystal Structure of Hcp from Acinetobacter baumannii: A Component of the Type VI Secretion System.

    Directory of Open Access Journals (Sweden)

    Federico M Ruiz

    Full Text Available The type VI secretion system (T6SS is a bacterial macromolecular machine widely distributed in Gram-negative bacteria, which transports effector proteins into eukaryotic host cells or other bacteria. Membrane complexes and a central tubular structure, which resembles the tail of contractile bacteriophages, compose the T6SS. One of the proteins forming this tube is the hemolysin co-regulated protein (Hcp, which acts as virulence factor, as transporter of effectors and as a chaperone. In this study, we present the structure of Hcp from Acinetobacter baumannii, together with functional and oligomerization studies. The structure of this protein exhibits a tight β barrel formed by two β sheets and flanked at one side by a short α-helix. Six Hcp molecules associate to form a donut-shaped hexamer, as observed in both the crystal structure and solution. These results emphasize the importance of this oligomerization state in this family of proteins, despite the low similarity of sequence among them. The structure presented in this study is the first one for a protein forming part of a functional T6SS from A. baumannii. These results will help us to understand the mechanism and function of this secretion system in this opportunistic nosocomial pathogen.

  2. Contribution of the Pseudomonas fluorescens MFE01 Type VI Secretion System to Biofilm Formation.

    Directory of Open Access Journals (Sweden)

    Mathias Gallique

    Full Text Available Type VI secretion systems (T6SSs are widespread in Gram-negative bacteria, including Pseudomonas. These macromolecular machineries inject toxins directly into prokaryotic or eukaryotic prey cells. Hcp proteins are structural components of the extracellular part of this machinery. We recently reported that MFE01, an avirulent strain of Pseudomonas fluorescens, possesses at least two hcp genes, hcp1 and hcp2, encoding proteins playing important roles in interbacterial interactions. Indeed, P. fluorescens MFE01 can immobilise and kill diverse bacteria of various origins through the action of the Hcp1 or Hcp2 proteins of the T6SS. We show here that another Hcp protein, Hcp3, is involved in killing prey cells during co-culture on solid medium. Even after the mutation of hcp1, hcp2, or hcp3, MFE01 impaired biofilm formation by MFP05, a P. fluorescens strain isolated from human skin. These mutations did not reduce P. fluorescens MFE01 biofilm formation, but the three Hcp proteins were required for the completion of biofilm maturation. Moreover, a mutant with a disruption of one of the unique core component genes, MFE01ΔtssC, was unable to produce its own biofilm or inhibit MFP05 biofilm formation. Finally, MFE01 did not produce detectable N-acyl-homoserine lactones for quorum sensing, a phenomenon reported for many other P. fluorescens strains. Our results suggest a role for the T6SS in communication between bacterial cells, in this strain, under biofilm conditions.

  3. Type VI Secretion System Transports Zn2+ to Combat Multiple Stresses and Host Immunity.

    Directory of Open Access Journals (Sweden)

    Tietao Wang

    2015-07-01

    Full Text Available Type VI secretion systems (T6SSs are widespread multi-component machineries that translocate effectors into either eukaryotic or prokaryotic cells, for virulence or for interbacterial competition. Herein, we report that the T6SS-4 from Yersinia pseudotuberculosis displays an unexpected function in the transportation of Zn2+ to combat diverse stresses and host immunity. Environmental insults such as oxidative stress induce the expression of T6SS-4 via OxyR, the transcriptional factor that also regulates many oxidative response genes. Zinc transportation is achieved by T6SS-4-mediated translocation of a novel Zn2+-binding protein substrate YezP (YPK_3549, which has the capacity to rescue the sensitivity to oxidative stress exhibited by T6SS-4 mutants when added to extracellular milieu. Disruption of the classic zinc transporter ZnuABC together with T6SS-4 or yezP results in mutants that almost completely lost virulence against mice, further highlighting the importance of T6SS-4 in resistance to host immunity. These results assigned an unconventional role to T6SSs, which will lay the foundation for studying novel mechanisms of metal ion uptake by bacteria and the role of this process in their resistance to host immunity and survival in harmful environments.

  4. Uranium(VI) Reduction by Nanoscale Zerovalent Iron in Anoxic Batch Systems

    International Nuclear Information System (INIS)

    Yan, Sen; Hua, Bin; Bao, Zhengyu; Yang, John; Liu, Chongxuan; Deng, Baolin

    2010-01-01

    This study investigated the influences of pH, bicarbonate, and calcium on U(VI) adsorption and reduction by synthetic nanosize zero valent iron (nano Fe 0 ) particles under an anoxic condition. The results showed that about 87.1%, 82.7% and 78.3% of U(VI) could be reduced within 96 hours in the presence of 10 mM bicarbonate at pHs 6.92, 8.03 and 9.03, respectively. The rates of U(VI) reduction and adsorption by nano Fe 0 , however, varied significantly with increasing pH and concentrations of bicarbonate and/or calcium. Solid phase analysis by X-ray photoelectron spectroscopy confirmed the formation of UO 2 and iron (hydr)oxides as a result of the redox interactions between adsorbed U(VI) and nano Fe 0 . This study highlights the potential important role of groundwater chemical composition in controlling the rates of U(VI) reductive immobilization using nano Fe 0 in subsurface environments.

  5. Diversification of Type VI Secretion System Toxins Reveals Ancient Antagonism among Bee Gut Microbes

    Directory of Open Access Journals (Sweden)

    Margaret I. Steele

    2017-12-01

    Full Text Available Microbial communities are shaped by interactions among their constituent members. Some Gram-negative bacteria employ type VI secretion systems (T6SSs to inject protein toxins into neighboring cells. These interactions have been theorized to affect the composition of host-associated microbiomes, but the role of T6SSs in the evolution of gut communities is not well understood. We report the discovery of two T6SSs and numerous T6SS-associated Rhs toxins within the gut bacteria of honey bees and bumble bees. We sequenced the genomes of 28 strains of Snodgrassella alvi, a characteristic bee gut microbe, and found tremendous variability in their Rhs toxin complements: altogether, these strains appear to encode hundreds of unique toxins. Some toxins are shared with Gilliamella apicola, a coresident gut symbiont, implicating horizontal gene transfer as a source of toxin diversity in the bee gut. We use data from a transposon mutagenesis screen to identify toxins with antibacterial function in the bee gut and validate the function and specificity of a subset of these toxin and immunity genes in Escherichia coli. Using transcriptome sequencing, we demonstrate that S. alvi T6SSs and associated toxins are upregulated in the gut environment. We find that S. alvi Rhs loci have a conserved architecture, consistent with the C-terminal displacement model of toxin diversification, with Rhs toxins, toxin fragments, and cognate immunity genes that are expressed and confer strong fitness effects in vivo. Our findings of T6SS activity and Rhs toxin diversity suggest that T6SS-mediated competition may be an important driver of coevolution within the bee gut microbiota.

  6. Unique substrates secreted by the type VI secretion system of Francisella tularensis during intramacrophage infection.

    Science.gov (United States)

    Bröms, Jeanette E; Meyer, Lena; Sun, Kun; Lavander, Moa; Sjöstedt, Anders

    2012-01-01

    Gram-negative bacteria have evolved sophisticated secretion machineries specialized for the secretion of macromolecules important for their life cycles. The Type VI secretion system (T6SS) is the most widely spread bacterial secretion machinery and is encoded by large, variable gene clusters, often found to be essential for virulence. The latter is true for the atypical T6SS encoded by the Francisella pathogenicity island (FPI) of the highly pathogenic, intracellular bacterium Francisella tularensis. We here undertook a comprehensive analysis of the intramacrophage secretion of the 17 FPI proteins of the live vaccine strain, LVS, of F. tularensis. All were expressed as fusions to the TEM β-lactamase and cleavage of the fluorescent substrate CCF2-AM, a direct consequence of the delivery of the proteins into the macrophage cytosol, was followed over time. The FPI proteins IglE, IglC, VgrG, IglI, PdpE, PdpA, IglJ and IglF were all secreted, which was dependent on the core components DotU, VgrG, and IglC, as well as IglG. In contrast, the method was not directly applicable on F. novicida U112, since it showed very intense native β-lactamase secretion due to FTN_1072. Its role was proven by ectopic expression in trans in LVS. We did not observe secretion of any of the LVS substrates VgrG, IglJ, IglF or IglI, when tested in a FTN_1072 deficient strain of F. novicida, whereas IglE, IglC, PdpA and even more so PdpE were all secreted. This suggests that there may be fundamental differences in the T6S mechanism among the Francisella subspecies. The findings further corroborate the unusual nature of the T6SS of F. tularensis since almost all of the identified substrates are unique to the species.

  7. Integrated Interventions to Tackle Antimicrobial Usage in Animal Production Systems: The ViParc Project in Vietnam

    Directory of Open Access Journals (Sweden)

    Juan J. Carrique-Mas

    2017-06-01

    Full Text Available Antimicrobial usage and antimicrobial resistance (AMR in animal production is now recognized to be an important contributor to the global problem of AMR. Initiatives to curb indiscriminate antimicrobial use in animal production are currently being discussed in many low- and middle-income countries. Well-designed, scientifically sound interventions aimed to tackle excessive antimicrobial usage should provide scientists and policy makers with evidence of the highest quality to guide changes in policy and to formulate better targeted research initiatives. However, since large-scale interventions are costly, they require careful planning in order not to waste valuable resources. Here, we describe the components of the ViParc project (www.viparc.org, one of the first large-scale interventions of its kind to tackle excessive antimicrobial usage in Southeast Asian animal production systems. The project has been formulated as a “randomized before-and-after controlled study” targeting small-scale poultry farms in the Mekong Delta region of Vietnam. It aims to provide farmers with a locally-adapted veterinary support service to help them reduce their reliance on antimicrobials. ViParc has been developed in the backdrop of efforts by the Government of Vietnam to develop a National Action Plan to reduce Antimicrobials in Livestock and Aquaculture. Crucially, the project integrates socio-economic analyses that will provide insights into the drivers of antimicrobial usage, as well as an assessment of the cost-effectiveness of the proposed intervention. Information generated from ViParc should help the Government of Vietnam refine its policies to curb excessive antimicrobial usage in poultry production, while lessons from ViParc will help tackle excessive antimicrobial usage in other productions systems in Vietnam and in the broader Southeast Asian region.

  8. Integrated Interventions to Tackle Antimicrobial Usage in Animal Production Systems: The ViParc Project in Vietnam.

    Science.gov (United States)

    Carrique-Mas, Juan J; Rushton, Jonathan

    2017-01-01

    Antimicrobial usage and antimicrobial resistance (AMR) in animal production is now recognized to be an important contributor to the global problem of AMR. Initiatives to curb indiscriminate antimicrobial use in animal production are currently being discussed in many low- and middle-income countries. Well-designed, scientifically sound interventions aimed to tackle excessive antimicrobial usage should provide scientists and policy makers with evidence of the highest quality to guide changes in policy and to formulate better targeted research initiatives. However, since large-scale interventions are costly, they require careful planning in order not to waste valuable resources. Here, we describe the components of the ViParc project (www.viparc.org), one of the first large-scale interventions of its kind to tackle excessive antimicrobial usage in Southeast Asian animal production systems. The project has been formulated as a "randomized before-and-after controlled study" targeting small-scale poultry farms in the Mekong Delta region of Vietnam. It aims to provide farmers with a locally-adapted veterinary support service to help them reduce their reliance on antimicrobials. ViParc has been developed in the backdrop of efforts by the Government of Vietnam to develop a National Action Plan to reduce Antimicrobials in Livestock and Aquaculture. Crucially, the project integrates socio-economic analyses that will provide insights into the drivers of antimicrobial usage, as well as an assessment of the cost-effectiveness of the proposed intervention. Information generated from ViParc should help the Government of Vietnam refine its policies to curb excessive antimicrobial usage in poultry production, while lessons from ViParc will help tackle excessive antimicrobial usage in other productions systems in Vietnam and in the broader Southeast Asian region.

  9. Reductive immobilization of U(VI) in Fe(III) oxide-reducing subsurface sediments: Analysis of coupled microbial-geochemical processes in experimental reactive transport systems. Final Scientific/Technical Report-EMSP 73914

    International Nuclear Information System (INIS)

    Eric E. Roden Matilde M. Urrutia Mark O. Barnett Clifford R. Lange

    2005-01-01

    ) reduction is likely to be less efficient in natural soils and sediments than would be inferred from studies with synthetic Fe(III) oxides. A key implication of these findings is that production of Fe(II)-enriched sediments during one-time (or periodic) stimulation of DMRB activity is not likely to permit efficient long-term abiotic conversion of U(VI) to U(IV) in biogenic redox barriers designed to prevent far-field subsurface U(VI) migration. Instead our results suggest that ongoing DMRB activity will be required to achieve maximal U(VI) reduction efficiency, and emphasize the need for detailed understanding of patterns of DMRB growth, colonization, and maintenance in physically and chemically heterogeneous subsurface environments in order to predict the effectiveness of subsurface U(VI) bioremediation operations. A final ''capstone'' aspect of experimental work on the project was to examine the potential for sustained coupled Fe(III) oxide and U(VI) reduction in experimental flow-through reactor systems (i.e. sediment columns and ''semicontinuous culture'' systems) that are conceptually analogous to hydrologically-open subsurface environments. The results conclusively demonstrated the potential for sustained removal of U(VI) from solution via DMRB activity in excess of the U(VI) sorption capacity of the natural mineral assemblages as determined in abiotic controls. In addition, the abundance of sorbed U(VI) (a potential long-term source of U(VI) to the aqueous phase) was much lower in the biotic vs. abiotic systems. The latter results agree with other project findings which demonstrated the capacity for G. sulfurreducens to reduce sorbed U(VI). Throughout the project we have developed and refined a variety of reaction-based models of coupled Fe(III) oxide/U(VI) reduction, including a generalized model which accounts for the population dynamics of various respiratory microbial functional groups. These models have been employed in numerical simulations of both batch bench

  10. Burkholderia type VI secretion systems have distinct roles in eukaryotic and bacterial cell interactions.

    Directory of Open Access Journals (Sweden)

    Sandra Schwarz

    2010-08-01

    Full Text Available Bacteria that live in the environment have evolved pathways specialized to defend against eukaryotic organisms or other bacteria. In this manuscript, we systematically examined the role of the five type VI secretion systems (T6SSs of Burkholderia thailandensis (B. thai in eukaryotic and bacterial cell interactions. Consistent with phylogenetic analyses comparing the distribution of the B. thai T6SSs with well-characterized bacterial and eukaryotic cell-targeting T6SSs, we found that T6SS-5 plays a critical role in the virulence of the organism in a murine melioidosis model, while a strain lacking the other four T6SSs remained as virulent as the wild-type. The function of T6SS-5 appeared to be specialized to the host and not related to an in vivo growth defect, as ΔT6SS-5 was fully virulent in mice lacking MyD88. Next we probed the role of the five systems in interbacterial interactions. From a group of 31 diverse bacteria, we identified several organisms that competed less effectively against wild-type B. thai than a strain lacking T6SS-1 function. Inactivation of T6SS-1 renders B. thai greatly more susceptible to cell contact-induced stasis by Pseudomonas putida, Pseudomonas fluorescens and Serratia proteamaculans-leaving it 100- to 1000-fold less fit than the wild-type in competition experiments with these organisms. Flow cell biofilm assays showed that T6S-dependent interbacterial interactions are likely relevant in the environment. B. thai cells lacking T6SS-1 were rapidly displaced in mixed biofilms with P. putida, whereas wild-type cells persisted and overran the competitor. Our data show that T6SSs within a single organism can have distinct functions in eukaryotic versus bacterial cell interactions. These systems are likely to be a decisive factor in the survival of bacterial cells of one species in intimate association with those of another, such as in polymicrobial communities present both in the environment and in many infections.

  11. 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 ...

  12. 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....

  13. A type VI secretion system is involved in Pseudomonas fluorescens bacterial competition.

    Directory of Open Access Journals (Sweden)

    Victorien Decoin

    Full Text Available Protein secretion systems are crucial mediators of bacterial interactions with other organisms. Among them, the type VI secretion system (T6SS is widespread in Gram-negative bacteria and appears to inject toxins into competitor bacteria and/or eukaryotic cells. Major human pathogens, such as Vibrio cholerae, Burkholderia and Pseudomonas aeruginosa, express T6SSs. Bacteria prevent self-intoxication by their own T6SS toxins by producing immunity proteins, which interact with the cognate toxins. We describe here an environmental P. fluorescens strain, MFE01, displaying an uncommon oversecretion of Hcp (hemolysin-coregulated protein and VgrG (valine-glycine repeat protein G into the culture medium. These proteins are characteristic components of a functional T6SS. The aim of this study was to attribute a role to this energy-consuming overexpression of the T6SS. The genome of MFE01 contains at least two hcp genes (hcp1 and hcp2, suggesting that there may be two putative T6SS clusters. Phenotypic studies have shown that MFE01 is avirulent against various eukaryotic cell models (amebas, plant or animal cell models, but has antibacterial activity against a wide range of competitor bacteria, including rhizobacteria and clinical bacteria. Depending on the prey cell, mutagenesis of the hcp2 gene in MFE01 abolishes or reduces this antibacterial killing activity. Moreover, the introduction of T6SS immunity proteins from S. marcescens, which is not killed by MFE01, protects E. coli against MFE01 killing. These findings suggest that the protein encoded by hcp2 is involved in the killing activity of MFE01 mediated by effectors of the T6SS targeting the peptidoglycan of Gram-negative bacteria. Our results indicate that MFE01 can protect potato tubers against Pectobacterium atrosepticum, which causes tuber soft rot. Pseudomonas fluorescens is often described as a major PGPR (plant growth-promoting rhizobacterium, and our results suggest that there may be a

  14. Gene Expression of Type VI Secretion System Associated with Environmental Survival in Acidovorax avenae subsp. avenae by Principle Component Analysis

    OpenAIRE

    Cui, Zhouqi; Jin, Guoqiang; Li, Bin; Kakar, Kaleem; Ojaghian, Mohammad; Wang, Yangli; Xie, Guanlin; Sun, Guochang

    2015-01-01

    Valine glycine repeat G (VgrG) proteins are regarded as one of two effectors of Type VI secretion system (T6SS) which is a complex multi-component secretion system. In this study, potential biological roles of T6SS structural and VgrG genes in a rice bacterial pathogen, Acidovorax avenae subsp. avenae (Aaa) RS-1, were evaluated under seven stress conditions using principle component analysis of gene expression. The results showed that growth of the pathogen was reduced by H2O2 and paraquat-i...

  15. Proteomic Identification of Novel Secreted Antibacterial Toxins of the Serratia marcescens Type VI Secretion System*

    Science.gov (United States)

    Fritsch, Maximilian J.; Trunk, Katharina; Diniz, Juliana Alcoforado; Guo, Manman; Trost, Matthias; Coulthurst, Sarah J.

    2013-01-01

    It has recently become apparent that the Type VI secretion system (T6SS) is a complex macromolecular machine used by many bacterial species to inject effector proteins into eukaryotic or bacterial cells, with significant implications for virulence and interbacterial competition. “Antibacterial” T6SSs, such as the one elaborated by the opportunistic human pathogen, Serratia marcescens, confer on the secreting bacterium the ability to rapidly and efficiently kill rival bacteria. Identification of secreted substrates of the T6SS is critical to understanding its role and ability to kill other cells, but only a limited number of effectors have been reported so far. Here we report the successful use of label-free quantitative mass spectrometry to identify at least eleven substrates of the S. marcescens T6SS, including four novel effector proteins which are distinct from other T6SS-secreted proteins reported to date. These new effectors were confirmed as antibacterial toxins and self-protecting immunity proteins able to neutralize their cognate toxins were identified. The global secretomic study also unexpectedly revealed that protein phosphorylation-based post-translational regulation of the S. marcescens T6SS differs from that of the paradigm, H1-T6SS of Pseudomonas aeruginosa. Combined phosphoproteomic and genetic analyses demonstrated that conserved PpkA-dependent threonine phosphorylation of the T6SS structural component Fha is required for T6SS activation in S. marcescens and that the phosphatase PppA can reverse this modification. However, the signal and mechanism of PpkA activation is distinct from that observed previously and does not appear to require cell–cell contact. Hence this study has not only demonstrated that new and species-specific portfolios of antibacterial effectors are secreted by the T6SS, but also shown for the first time that PpkA-dependent post-translational regulation of the T6SS is tailored to fit the needs of different bacterial

  16. Dual expression profile of type VI secretion system immunity genes protects pandemic Vibrio cholerae.

    Directory of Open Access Journals (Sweden)

    Sarah T Miyata

    Full Text Available The Vibrio cholerae type VI secretion system (T6SS assembles as a molecular syringe that injects toxic protein effectors into both eukaryotic and prokaryotic cells. We previously reported that the V. cholerae O37 serogroup strain V52 maintains a constitutively active T6SS to kill other Gram-negative bacteria while being immune to attack by kin bacteria. The pandemic O1 El Tor V. cholerae strain C6706 is T6SS-silent under laboratory conditions as it does not produce T6SS structural components and effectors, and fails to kill Escherichia coli prey. Yet, C6706 exhibits full resistance when approached by T6SS-active V52. These findings suggested that an active T6SS is not required for immunity against T6SS-mediated virulence. Here, we describe a dual expression profile of the T6SS immunity protein-encoding genes tsiV1, tsiV2, and tsiV3 that provides pandemic V. cholerae strains with T6SS immunity and allows T6SS-silent strains to maintain immunity against attacks by T6SS-active bacterial neighbors. The dual expression profile allows transcription of the three genes encoding immunity proteins independently of other T6SS proteins encoded within the same operon. One of these immunity proteins, TsiV2, protects against the T6SS effector VasX which is encoded immediately upstream of tsiV2. VasX is a secreted, lipid-binding protein that we previously characterized with respect to T6SS-mediated virulence towards the social amoeba Dictyostelium discoideum. Our data suggest the presence of an internal promoter in the open reading frame of vasX that drives expression of the downstream gene tsiV2. Furthermore, VasX is shown to act in conjunction with VasW, an accessory protein to VasX, to compromise the inner membrane of prokaryotic target cells. The dual regulatory profile of the T6SS immunity protein-encoding genes tsiV1, tsiV2, and tsiV3 permits V. cholerae to tightly control T6SS gene expression while maintaining immunity to T6SS activity.

  17. The structure of Serratia marcescens Lip, a membrane-bound component of the type VI secretion system

    International Nuclear Information System (INIS)

    Rao, Vincenzo A.; Shepherd, Sharon M.; English, Grant; Coulthurst, Sarah J.; Hunter, William N.

    2011-01-01

    The high-resolution crystal structure of S. marcescens Lip reveals a new member of the transthyretin family of proteins. Lip, a core component of the type VI secretion apparatus, is localized to the outer membrane and is positioned to interact with other proteins forming this complex system. Lip is a membrane-bound lipoprotein and a core component of the type VI secretion system found in Gram-negative bacteria. The structure of a Lip construct (residues 29–176) from Serratia marcescens (SmLip) has been determined at 1.92 Å resolution. Experimental phases were derived using a single-wavelength anomalous dispersion approach on a sample cocrystallized with iodide. The membrane localization of the native protein was confirmed. The structure is that of the globular domain lacking only the lipoprotein signal peptide and the lipidated N-terminus of the mature protein. The protein fold is dominated by an eight-stranded β-sandwich and identifies SmLip as a new member of the transthyretin family of proteins. Transthyretin and the only other member of the family fold, 5-hydroxyisourate hydrolase, form homotetramers important for their function. The asymmetric unit of SmLip is a tetramer with 222 symmetry, but the assembly is distinct from that previously noted for the transthyretin protein family. However, structural comparisons and bacterial two-hybrid data suggest that the SmLip tetramer is not relevant to its role as a core component of the type VI secretion system, but rather reflects a propensity for SmLip to participate in protein–protein interactions. A relatively low level of sequence conservation amongst Lip homologues is noted and is restricted to parts of the structure that might be involved in interactions with physiological partners

  18. The structure of Serratia marcescens Lip, a membrane-bound component of the type VI secretion system

    Energy Technology Data Exchange (ETDEWEB)

    Rao, Vincenzo A.; Shepherd, Sharon M.; English, Grant; Coulthurst, Sarah J.; Hunter, William N., E-mail: w.n.hunter@dundee.ac.uk [College of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland (United Kingdom)

    2011-12-01

    The high-resolution crystal structure of S. marcescens Lip reveals a new member of the transthyretin family of proteins. Lip, a core component of the type VI secretion apparatus, is localized to the outer membrane and is positioned to interact with other proteins forming this complex system. Lip is a membrane-bound lipoprotein and a core component of the type VI secretion system found in Gram-negative bacteria. The structure of a Lip construct (residues 29–176) from Serratia marcescens (SmLip) has been determined at 1.92 Å resolution. Experimental phases were derived using a single-wavelength anomalous dispersion approach on a sample cocrystallized with iodide. The membrane localization of the native protein was confirmed. The structure is that of the globular domain lacking only the lipoprotein signal peptide and the lipidated N-terminus of the mature protein. The protein fold is dominated by an eight-stranded β-sandwich and identifies SmLip as a new member of the transthyretin family of proteins. Transthyretin and the only other member of the family fold, 5-hydroxyisourate hydrolase, form homotetramers important for their function. The asymmetric unit of SmLip is a tetramer with 222 symmetry, but the assembly is distinct from that previously noted for the transthyretin protein family. However, structural comparisons and bacterial two-hybrid data suggest that the SmLip tetramer is not relevant to its role as a core component of the type VI secretion system, but rather reflects a propensity for SmLip to participate in protein–protein interactions. A relatively low level of sequence conservation amongst Lip homologues is noted and is restricted to parts of the structure that might be involved in interactions with physiological partners.

  19. Optimization of the višnjica watercourse by the containment of the wastewater to the sewage system

    OpenAIRE

    Podržaj, Anže

    2012-01-01

    The thesis describes design of stormwater tanks with overflow according to German guidelines ATV-A 128E in terms of protecting stream Višnjica. The task is roughly consists of three parts. The introduction describes the area in question. It presents the problem of rapidly growing settlement Ivančna Gorica and the existing sewer system. More detailed are described the local streams and their pollution. In the central part are presented the German ATV guidelines. These standards describe the de...

  20. Dynamical systems in population biology

    CERN Document Server

    Zhao, Xiao-Qiang

    2017-01-01

    This research monograph provides an introduction to the theory of nonautonomous semiflows with applications to population dynamics. It develops dynamical system approaches to various evolutionary equations such as difference, ordinary, functional, and partial differential equations, and pays more attention to periodic and almost periodic phenomena. The presentation includes persistence theory, monotone dynamics, periodic and almost periodic semiflows, basic reproduction ratios, traveling waves, and global analysis of prototypical population models in ecology and epidemiology. Research mathematicians working with nonlinear dynamics, particularly those interested in applications to biology, will find this book useful. It may also be used as a textbook or as supplementary reading for a graduate special topics course on the theory and applications of dynamical systems. Dr. Xiao-Qiang Zhao is a University Research Professor at Memorial University of Newfoundland, Canada. His main research interests involve applied...

  1. Study of the characteristic response of the pressure control system for the design parameters of the new turbine control system, MARK VI, in Cofrentes Nuclear Power Plant

    International Nuclear Information System (INIS)

    Palomo anaya, M. J.; Ruiz Bueno, G.; Mora, J. A.; Vaquer, J. I.; Bucho, L.; Lopez, B.

    2010-01-01

    This paper presents the results of the study of the characteristic response of the ancient Pressure and Turbine Control System for the OCP-4300 Project in the Cofrentes Nuclear Power Plant, made by Tatiana Servicios Tecnologicos in collaboration with the Institute for Industrial, Radiophysical and Environmental Safety. This work was done as one of the preliminary work necessary for replacing the old control system by Mark VI.

  2. 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.

  3. Multiple stellar populations in Magellanic Cloud clusters. VI. A survey of multiple sequences and Be stars in young clusters

    Science.gov (United States)

    Milone, A. P.; Marino, A. F.; Di Criscienzo, M.; D'Antona, F.; Bedin, L. R.; Da Costa, G.; Piotto, G.; Tailo, M.; Dotter, A.; Angeloni, R.; Anderson, J.; Jerjen, H.; Li, C.; Dupree, A.; Granata, V.; Lagioia, E. P.; Mackey, A. D.; Nardiello, D.; Vesperini, E.

    2018-03-01

    The split main sequences (MSs) and extended MS turnoffs (eMSTOs) detected in a few young clusters have demonstrated that these stellar systems host multiple populations differing in a number of properties such as rotation and, possibly, age. We analyze Hubble Space Telescope photometry for thirteen clusters with ages between ˜40 and ˜1000 Myrs and of different masses. Our goal is to investigate for the first time the occurrence of multiple populations in a large sample of young clusters. We find that all the clusters exhibit the eMSTO phenomenon and that MS stars more massive than ˜1.6 M_⊙ define a blue and red MS, with the latter hosting the majority of MS stars. The comparison between the observations and isochrones suggests that the blue MSs are made of slow-rotating stars, while the red MSs host stars with rotational velocities close to the breakup value. About half of the bright MS stars in the youngest clusters are H-alpha emitters. These Be stars populate the red MS and the reddest part of the eMSTO thus supporting the idea that the red MS is made of fast rotators. We conclude that the split MS and the eMSTO are a common feature of young clusters in both Magellanic Clouds. The phenomena of a split MS and an eMSTO occur for stars that are more massive than a specific threshold which is independent of the host-cluster mass. As a by-product, we report the serendipitous discovery of a young SMC cluster, GALFOR1.

  4. 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.

  5. Integrating model of the Project Independence Evaluation System. Volume VI. Data documentation. Part II

    Energy Technology Data Exchange (ETDEWEB)

    Allen, B J

    1979-02-01

    This documentation describes the PIES Integrating Model as it existed on January 1, 1978. This Volume VI of six volumes is data documentation, containing the standard table data used for the Administrator's Report at the beginning of 1978, along with the primary data sources and the office responsible. It also contains a copy of a PIES Integrating Model Report with a description of its content. Following an overview chapter, Chapter II, Supply and Demand Data Tables and Sources for the Mid-range Scenario for Target Years 1985 and 1990, data on demand, price, and elasticity; coal; imports; oil and gas; refineries; synthetics, shale, and solar/geothermal; transportation; and utilities are presented. The following data on alternate scenarios are discussed: low and high demand; low and high oil and gas supply; refinery and oil and gas data assuming a 5% annual increase in real world oil prices. Chapter IV describes the solution output obtained from an execution of PIES.

  6. Aqueous U(VI) interaction with magnetite nanoparticles in a mixed flow reactor system: HR-XANES study

    International Nuclear Information System (INIS)

    Pidchenko, I; Heberling, F; Finck, N; Schild, D; Bohnert, E; Schäfer, T; Rothe, J; Geckeis, H; Vitova, T; Kvashnina, KO

    2016-01-01

    The redox variations and changes in local atomic environment of uranium (U) interacted with the magnetite nanoparticles were studied in a proof of principle experiment by the U L 3 and M 4 edges high energy resolution X-ray absorption near edge structure (HR-XANES) technique. We designed and applied a mixed flow reactor (MFR) set-up to maintain dynamic flow conditions during U-magnetite interactions. Formation of hydrolyzed, bi- and poly-nuclear U species were excluded by slow continuous injection of U(VI) (10 -6 M) and pH control integrated in the MFR set-up. The applied U HR-XANES technique is more sensitive to minor changes in the U redox states and bonding compared to the conventional XANES method. Major U(VI) contribution in uranyl type of bonding is found in the magnetite nanoparticles after three days operation time of the MFR. Indications for shortening of the U-O axial bond length for the magnetite compared to the maghemite system are present too. (paper)

  7. Vibrio parahaemolyticus type VI secretion system 1 is activated in marine conditions to target bacteria, and is differentially regulated from system 2.

    Directory of Open Access Journals (Sweden)

    Dor Salomon

    Full Text Available Vibrio parahaemolyticus is a marine bacterium that thrives in warm climates. It is a leading cause of gastroenteritis resulting from consumption of contaminated uncooked shellfish. This bacterium harbors two putative type VI secretion systems (T6SS. T6SSs are widespread protein secretion systems found in many Gram-negative bacteria, and are often tightly regulated. For many T6SSs studied to date, the conditions and cues, as well as the regulatory mechanisms that control T6SS activity are unknown. In this study, we characterized the environmental conditions and cues that activate both V. parahaemolyticus T6SSs, and identified regulatory mechanisms that control T6SS gene expression and activity. We monitored the expression and secretion of the signature T6SS secreted proteins Hcp1 and Hcp2, and found that both T6SSs are differentially regulated by quorum sensing and surface sensing. We also showed that T6SS1 and T6SS2 require different temperature and salinity conditions to be active. Interestingly, T6SS1, which is found predominantly in clinical isolates, was most active under warm marine-like conditions. Moreover, we found that T6SS1 has anti-bacterial activity under these conditions. In addition, we identified two transcription regulators in the T6SS1 gene cluster that regulate Hcp1 expression, but are not required for immunity against self-intoxication. Further examination of environmental isolates revealed a correlation between the presence of T6SS1 and virulence of V. parahaemolyticus against other bacteria, and we also showed that different V. parahaemolyticus isolates can outcompete each other. We propose that T6SS1 and T6SS2 play different roles in the V. parahaemolyticus lifestyles, and suggest a role for T6SS1 in enhancing environmental fitness of V. parahaemolyticus in marine environments when competing for a niche in the presence of other bacterial populations.

  8. Face, content, and construct validity of the EndoViS training system for objective assessment of psychomotor skills of laparoscopic surgeons.

    Science.gov (United States)

    Escamirosa, Fernando Pérez; Flores, Ricardo Manuel Ordorica; García, Ignacio Oropesa; Vidal, Cristian Rubén Zalles; Martínez, Arturo Minor

    2015-11-01

    The aim of this study is to present face, content, and constructs validity of the endoscopic orthogonal video system (EndoViS) training system and determines its efficiency as a training and objective assessment tool of the surgeons' psychomotor skills. Thirty-five surgeons and medical students participated in this study: 11 medical students, 19 residents, and 5 experts. All participants performed four basic skill tasks using conventional laparoscopic instruments and EndoViS training system. Subsequently, participants filled out a questionnaire regarding the design, realism, overall functionality, and its capabilities to train hand-eye coordination and depth perception, rated on a 5-point Likert scale. Motion data of the instruments were obtained by means of two webcams built into a laparoscopic physical trainer. To identify the surgical instruments in the images, colored markers were placed in each instrument. Thirteen motion-related metrics were used to assess laparoscopic performance of the participants. Statistical analysis of performance was made between novice, intermediate, and expert groups. Internal consistency of all metrics was analyzed with Cronbach's α test. Overall scores about features of the EndoViS system were positives. Participants agreed with the usefulness of tasks and the training capacities of EndoViS system (score >4). Results presented significant differences in the execution of three skill tasks performed by participants. Seven metrics showed construct validity for assessment of performance with high consistency levels. EndoViS training system has been successfully validated. Results showed that EndoViS was able to differentiate between participants of varying laparoscopic experience. This simulator is a useful and effective tool to objectively assess laparoscopic psychomotor skills of the surgeons.

  9. Teacher's Guide in Population Education for Social Studies, Grades I-VI. Elementary Level. (Revised for Muslim Filipinos).

    Science.gov (United States)

    Department of Education and Culture, Manila (Philippines).

    Revised to be in accordance with the customs, traditions, beliefs, and practices of the Muslim Filipinos, these elementary-level social studies units will help Filipino children understand world population problems and develop the necessary skills, attitudes, and values that will lead them to make rational decisions about population matters,…

  10. Unraveling the Long-Term Effects of Cr(VI on the Performance and Microbial Community of Nitrifying Activated Sludge System

    Directory of Open Access Journals (Sweden)

    Xingang Wang

    2017-11-01

    Full Text Available The long-term effects of different influent Cr(VI concentrations (0–0.5 mg L−1 on the nitrification activities and microbial community structures of nitrifying activated sludge system were investigated in this study. Results showed that the performance of ammonia oxidation was significantly inhibited, and the effluent concentration of ammonia nitrogen (NH4+-N increased markedly when the influent Cr(VI loading was equal or greater than 0.2 mg L−1. The specific oxygen utilization rate (SOUR, specific ammonium oxidation rate (SAOR, and specific nitrite oxidation rate (SNOR of the system decreased from 53.24, 6.31, and 7.33 mg N g−1 VSS h−1 to 18.17, 1.68, and 2.88 mg N g−1 VSS h−1, respectively, with an increase of Cr(VI concentration from 0 to 0.5 mg L−1. The protein/polysaccharide (PN/PS ratio increased with the increasing Cr(VI concentration, indicating that excessive PN secreted by microorganisms was conducive to resisting the toxicity of Cr(VI. High-throughput sequencing revealed that the relative abundance of ammonia-oxidizing bacteria (Nitrospira and nitrite-oxidizing bacteria (Nitrosomonas and Nitrosospira all decreased with the increasing Cr(VI concentration, and ammonia-oxidizing bacteria were more sensitive to heavy metal toxicity than nitrite-oxidizing bacteria. The activities of nitrifying activated sludge system could not be completely recovered after a 30-d recovery process.

  11. Analytical use of zide ion. Chemical equilibrium studies and correlates in U(VI)/N3 and Co(III)/N3 systems

    International Nuclear Information System (INIS)

    Silva, T.V. da.

    1984-01-01

    A monographic study about the azide ion and its structure, as well as, references about the uranyl ion in aqueous medium, and its possible hydrolysis products are shown. Spectral studies of the U(VI), Fe (III) and Cu(II) systems, in azide medium are analyzed. (M.J.C.) [pt

  12. Complete Genome Sequences of Plasmid-Bearing Multidrug-Resistant Campylobacter jejuni and Campylobacter coli Strains with Type VI Secretion Systems, Isolated from Retail Turkey and Pork

    OpenAIRE

    Marasini, Daya; Fakhr, Mohamed K.

    2017-01-01

    ABSTRACT We report the complete genome sequences of multidrug-resistant Campylobacter jejuni and Campylobacter coli isolated from retail turkey and pork, respectively. The chromosomes of these two isolates contained type VI secretion system genes. The two isolates also harbored large plasmids with antimicrobial resistance genes possibly contributing to their multidrug resistance.

  13. The Type VI Secretion System Engages a Redox-Regulated Dual-Functional Heme Transporter for Zinc Acquisition

    Directory of Open Access Journals (Sweden)

    Meiru Si

    2017-07-01

    Full Text Available The type VI secretion system was recently reported to be involved in zinc acquisition, but the underlying mechanism remains unclear. Here, we report that Burkholderia thailandensis T6SS4 is involved in zinc acquisition via secretion of a zinc-scavenging protein, TseZ, that interacts with the outer membrane heme transporter HmuR. We find that HmuR is a redox-regulated dual-functional transporter that transports heme iron under normal conditions but zinc upon sensing extracellular oxidative stress, triggered by formation of an intramolecular disulfide bond. Acting as the first line of defense against oxidative stress, HmuR not only guarantees an immediate response to the changing environment but also provides a fine-tuned mechanism that allows a gradual response to perceived stress. The T6SS/HmuR-mediated active zinc transport system is also involved in bacterial virulence and contact-independent bacterial competition. We describe a sophisticated bacterial zinc acquisition mechanism affording insights into the role of metal ion transport systems.

  14. 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.

  15. Acute Hepatopancreatic Necrosis Disease-Causing Vibrio parahaemolyticus Strains Maintain an Antibacterial Type VI Secretion System with Versatile Effector Repertoires.

    Science.gov (United States)

    Li, Peng; Kinch, Lisa N; Ray, Ann; Dalia, Ankur B; Cong, Qian; Nunan, Linda M; Camilli, Andrew; Grishin, Nick V; Salomon, Dor; Orth, Kim

    2017-07-01

    Acute hepatopancreatic necrosis disease (AHPND) is a newly emerging shrimp disease that has severely damaged the global shrimp industry. AHPND is caused by toxic strains of Vibrio parahaemolyticus that have acquired a "selfish plasmid" encoding the deadly binary toxins PirA vp /PirB vp To better understand the repertoire of virulence factors in AHPND-causing V. parahaemolyticus , we conducted a comparative analysis using the genome sequences of the clinical strain RIMD2210633 and of environmental non-AHPND and toxic AHPND isolates of V. parahaemolyticus Interestingly, we found that all of the AHPND strains, but none of the non-AHPND strains, harbor the antibacterial type VI secretion system 1 (T6SS1), which we previously identified and characterized in the clinical isolate RIMD2210633. This finding suggests that the acquisition of this T6SS might confer to AHPND-causing V. parahaemolyticus a fitness advantage over competing bacteria and facilitate shrimp infection. Additionally, we found highly dynamic effector loci in the T6SS1 of AHPND-causing strains, leading to diverse effector repertoires. Our discovery provides novel insights into AHPND-causing pathogens and reveals a potential target for disease control. IMPORTANCE Acute hepatopancreatic necrosis disease (AHPND) is a serious disease that has caused severe damage and significant financial losses to the global shrimp industry. To better understand and prevent this shrimp disease, it is essential to thoroughly characterize its causative agent, Vibrio parahaemolyticus Although the plasmid-encoded binary toxins PirA vp /PirB vp have been shown to be the primary cause of AHPND, it remains unknown whether other virulent factors are commonly present in V. parahaemolyticus and might play important roles during shrimp infection. Here, we analyzed the genome sequences of clinical, non-AHPND, and AHPND strains to characterize their repertoires of key virulence determinants. Our studies reveal that an antibacterial type

  16. Gene Expression of Type VI Secretion System Associated with Environmental Survival in Acidovorax avenae subsp. avenae by Principle Component Analysis

    Directory of Open Access Journals (Sweden)

    Zhouqi Cui

    2015-09-01

    Full Text Available Valine glycine repeat G (VgrG proteins are regarded as one of two effectors of Type VI secretion system (T6SS which is a complex multi-component secretion system. In this study, potential biological roles of T6SS structural and VgrG genes in a rice bacterial pathogen, Acidovorax avenae subsp. avenae (Aaa RS-1, were evaluated under seven stress conditions using principle component analysis of gene expression. The results showed that growth of the pathogen was reduced by H2O2 and paraquat-induced oxidative stress, high salt, low temperature, and vgrG mutation, compared to the control. However, pathogen growth was unaffected by co-culture with a rice rhizobacterium Burkholderia seminalis R456. In addition, expression of 14 T6SS structural and eight vgrG genes was significantly changed under seven conditions. Among different stress conditions, high salt, and low temperature showed a higher effect on the expression of T6SS gene compared with host infection and other environmental conditions. As a first report, this study revealed an association of T6SS gene expression of the pathogen with the host infection, gene mutation, and some common environmental stresses. The results of this research can increase understanding of the biological function of T6SS in this economically-important pathogen of rice.

  17. Gene Expression of Type VI Secretion System Associated with Environmental Survival in Acidovorax avenae subsp. avenae by Principle Component Analysis.

    Science.gov (United States)

    Cui, Zhouqi; Jin, Guoqiang; Li, Bin; Kakar, Kaleem Ullah; Ojaghian, Mohammad Reza; Wang, Yangli; Xie, Guanlin; Sun, Guochang

    2015-09-11

    Valine glycine repeat G (VgrG) proteins are regarded as one of two effectors of Type VI secretion system (T6SS) which is a complex multi-component secretion system. In this study, potential biological roles of T6SS structural and VgrG genes in a rice bacterial pathogen, Acidovorax avenae subsp. avenae (Aaa) RS-1, were evaluated under seven stress conditions using principle component analysis of gene expression. The results showed that growth of the pathogen was reduced by H₂O₂ and paraquat-induced oxidative stress, high salt, low temperature, and vgrG mutation, compared to the control. However, pathogen growth was unaffected by co-culture with a rice rhizobacterium Burkholderia seminalis R456. In addition, expression of 14 T6SS structural and eight vgrG genes was significantly changed under seven conditions. Among different stress conditions, high salt, and low temperature showed a higher effect on the expression of T6SS gene compared with host infection and other environmental conditions. As a first report, this study revealed an association of T6SS gene expression of the pathogen with the host infection, gene mutation, and some common environmental stresses. The results of this research can increase understanding of the biological function of T6SS in this economically-important pathogen of rice.

  18. Transit Timing Observations from Kepler. VI. Potentially Interesting Candidate Systems from Fourier-based Statistical Tests

    OpenAIRE

    Steffen, Jason H.; Ford, Eric B.; Rowe, Jason F.; Fabrycky, Daniel C.; Holman, Matthew J.; Welsh, WIlliam F.; Batalha, Natalie M.; Borucki, William J.; Bryson, Steve; Caldwell, Douglas A.; Ciardi, David R.; Jenkins, Jon M.; Kjeldsen, Hans; Koch, David G.; Prša, Andrej

    2012-01-01

    We analyze the deviations of transit times from a linear ephemeris for the Kepler Objects of Interest (KOI) through Quarter six (Q6) of science data. We conduct two statistical tests for all KOIs and a related statistical test for all pairs of KOIs in multi-transiting systems. These tests identify several systems which show potentially interesting transit timing variations (TTVs). Strong TTV systems have been valuable for the confirmation of planets and their mass measurements. Many of the sy...

  19. Transit timing observations from Kepler. VI. Potentially interesting candidate systems from fourier-based statistical tests

    DEFF Research Database (Denmark)

    Steffen, J.H.; Ford, E.B.; Rowe, J.F.

    2012-01-01

    We analyze the deviations of transit times from a linear ephemeris for the Kepler Objects of Interest (KOI) through quarter six of science data. We conduct two statistical tests for all KOIs and a related statistical test for all pairs of KOIs in multi-transiting systems. These tests identify...... several systems which show potentially interesting transit timing variations (TTVs). Strong TTV systems have been valuable for the confirmation of planets and their mass measurements. Many of the systems identified in this study should prove fruitful for detailed TTV studies....

  20. TRANSIT TIMING OBSERVATIONS FROM KEPLER. VI. POTENTIALLY INTERESTING CANDIDATE SYSTEMS FROM FOURIER-BASED STATISTICAL TESTS

    Energy Technology Data Exchange (ETDEWEB)

    Steffen, Jason H. [Fermilab Center for Particle Astrophysics, P.O. Box 500, MS 127, Batavia, IL 60510 (United States); Ford, Eric B. [Astronomy Department, University of Florida, 211 Bryant Space Sciences Center, Gainesville, FL 32111 (United States); Rowe, Jason F.; Borucki, William J.; Bryson, Steve; Caldwell, Douglas A.; Jenkins, Jon M.; Koch, David G.; Sanderfer, Dwight T.; Seader, Shawn; Twicken, Joseph D. [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Fabrycky, Daniel C. [UCO/Lick Observatory, University of California, Santa Cruz, CA 95064 (United States); Holman, Matthew J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Welsh, William F. [Astronomy Department, San Diego State University, San Diego, CA 92182-1221 (United States); Batalha, Natalie M. [Department of Physics and Astronomy, San Jose State University, San Jose, CA 95192 (United States); Ciardi, David R. [NASA Exoplanet Science Institute/California Institute of Technology, Pasadena, CA 91125 (United States); Kjeldsen, Hans [Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); Prsa, Andrej, E-mail: jsteffen@fnal.gov [Department of Astronomy and Astrophysics, Villanova University, 800 East Lancaster Avenue, Villanova, PA 19085 (United States)

    2012-09-10

    We analyze the deviations of transit times from a linear ephemeris for the Kepler Objects of Interest (KOI) through quarter six of science data. We conduct two statistical tests for all KOIs and a related statistical test for all pairs of KOIs in multi-transiting systems. These tests identify several systems which show potentially interesting transit timing variations (TTVs). Strong TTV systems have been valuable for the confirmation of planets and their mass measurements. Many of the systems identified in this study should prove fruitful for detailed TTV studies.

  1. Energy Systems and Population Health

    Energy Technology Data Exchange (ETDEWEB)

    Ezzati, Majid; Bailis, Rob; Kammen, Daniel M.; Holloway, Tracey; Price, Lynn; Cifuentes, Luis A.; Barnes, Brendon; Chaurey, Akanksha; Dhanapala, Kiran N.

    2004-04-12

    to rural and urban health facilities allows increased delivery and coverage of 3 various health services and interventions such as tests and treatments, better storage of medicine and vaccines, disinfection of medical equipment by boiling or radiation, and more frequent and efficient health system encounters through mobile clinics or longer working hours; and so on. In fact, while the dominant view of development-energy-health linkages has been that improvements in energy and health are outcomes of the socioeconomic development process (e.g., the ''energy ladder'' framework discussed below), it has even been argued that access to higher quality energy sources and technologies can initiate a chain of demographic, health, and development outcomes by changing the household structure and socioeconomic relationships. For example, in addition to increased opportunities for food and income production, reduced infant mortality as a result of transition to cleaner fuels or increased coverage of vaccination with availability of refrigerators in rural clinics may initiate a process of ''demographic transition'' to low-mortality and low-fertility populations (14). Such a transition has historically been followed with further improvements in maternal and child health and increased female participation in the labor markets and other economic activities.

  2. Cr(VI) transport via a supported ionic liquid membrane containing CYPHOS IL101 as carrier: system analysis and optimization through experimental design strategies.

    Science.gov (United States)

    Rodríguez de San Miguel, Eduardo; Vital, Xóchitl; de Gyves, Josefina

    2014-05-30

    Chromium(VI) transport through a supported liquid membrane (SLM) system containing the commercial ionic liquid CYPHOS IL101 as carrier was studied. A reducing stripping phase was used as a mean to increase recovery and to simultaneously transform Cr(VI) into a less toxic residue for disposal or reuse. General functions which describe the time-depending evolution of the metal fractions in the cell compartments were defined and used in data evaluation. An experimental design strategy, using factorial and central-composite design matrices, was applied to assess the influence of the extractant, NaOH and citrate concentrations in the different phases, while a desirability function scheme allowed the synchronized optimization of depletion and recovery of the analyte. The mechanism for chromium permeation was analyzed and discussed to contribute to the understanding of the transfer process. The influence of metal concentration was evaluated as well. The presence of different interfering ions (Ca(2+), Al(3+), NO3(-), SO4(2-), and Cl(-)) at several Cr(VI): interfering ion ratios was studied through the use of a Plackett and Burman experimental design matrix. Under optimized conditions 90% of recovery was obtained from a feed solution containing 7mgL(-1) of Cr(VI) in 0.01moldm(-3) HCl medium after 5h of pertraction. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Batch system for study of Cr(VI) Bio sorption by dried waste activated sludge

    International Nuclear Information System (INIS)

    Farzadkia, M.; Gholami, M.; Darvishi Cheshmeh Soltani, R.; Yaghmaeian, K.; Shams Khorramabadi, G.

    2009-01-01

    Activated sludge from wastewater treatment systems contains both bacteria and protozoa. The cell wall of bacteria essentially consists of various compounds, such as carboxyl, acidic polysaccharides,lipids, amino acids and other components. (Author)

  4. Type VI secretion system contributes to Enterohemorrhagic Escherichia coli virulence by secreting catalase against host reactive oxygen species (ROS).

    Science.gov (United States)

    Wan, Baoshan; Zhang, Qiufen; Ni, Jinjing; Li, Shuxian; Wen, Donghua; Li, Jun; Xiao, Haihan; He, Ping; Ou, Hong-Yu; Tao, Jing; Teng, Qihui; Lu, Jie; Wu, Wenjuan; Yao, Yu-Feng

    2017-03-01

    Enterohemorrhagic Escherichia coli (EHEC) is one major type of contagious and foodborne pathogens. The type VI secretion system (T6SS) has been shown to be involved in the bacterial pathogenicity and bacteria-bacteria competition. Here, we show that EHEC could secrete a novel effector KatN, a Mn-containing catalase, in a T6SS-dependent manner. Expression of katN is promoted by RpoS and OxyR and repressed by H-NS, and katN contributes to bacterial growth under oxidative stress in vitro. KatN could be secreted into host cell cytosol after EHEC is phagocytized by macrophage, which leads to decreased level of intracellular reactive oxygen species (ROS) and facilitates the intramacrophage survival of EHEC. Finally, animal model results show that the deletion mutant of T6SS was attenuated in virulence compared with the wild type strain, while the deletion mutant of katN had comparable virulence to the wild type strain. Taken together, our findings suggest that EHEC could sense oxidative stress in phagosome and decrease the host cell ROS by secreting catalase KatN to facilitate its survival in the host cells.

  5. Type VI secretion system contributes to Enterohemorrhagic Escherichia coli virulence by secreting catalase against host reactive oxygen species (ROS.

    Directory of Open Access Journals (Sweden)

    Baoshan Wan

    2017-03-01

    Full Text Available Enterohemorrhagic Escherichia coli (EHEC is one major type of contagious and foodborne pathogens. The type VI secretion system (T6SS has been shown to be involved in the bacterial pathogenicity and bacteria-bacteria competition. Here, we show that EHEC could secrete a novel effector KatN, a Mn-containing catalase, in a T6SS-dependent manner. Expression of katN is promoted by RpoS and OxyR and repressed by H-NS, and katN contributes to bacterial growth under oxidative stress in vitro. KatN could be secreted into host cell cytosol after EHEC is phagocytized by macrophage, which leads to decreased level of intracellular reactive oxygen species (ROS and facilitates the intramacrophage survival of EHEC. Finally, animal model results show that the deletion mutant of T6SS was attenuated in virulence compared with the wild type strain, while the deletion mutant of katN had comparable virulence to the wild type strain. Taken together, our findings suggest that EHEC could sense oxidative stress in phagosome and decrease the host cell ROS by secreting catalase KatN to facilitate its survival in the host cells.

  6. Francisella requires dynamic type VI secretion system and ClpB to deliver effectors for phagosomal escape.

    Science.gov (United States)

    Brodmann, Maj; Dreier, Roland F; Broz, Petr; Basler, Marek

    2017-06-16

    Francisella tularensis is an intracellular pathogen that causes the fatal zoonotic disease tularaemia. Critical for its pathogenesis is the ability of the phagocytosed bacteria to escape into the cell cytosol. For this, the bacteria use a non-canonical type VI secretion system (T6SS) encoded on the Francisella pathogenicity island (FPI). Here we show that in F. novicida T6SS assembly initiates at the bacterial poles both in vitro and within infected macrophages. T6SS dynamics and function depends on the general purpose ClpB unfoldase, which specifically colocalizes with contracted sheaths and is required for their disassembly. T6SS assembly depends on iglF, iglG, iglI and iglJ, whereas pdpC, pdpD, pdpE and anmK are dispensable. Importantly, strains lacking pdpC and pdpD are unable to escape from phagosome, activate AIM2 inflammasome or cause disease in mice. This suggests that PdpC and PdpD are T6SS effectors involved in phagosome rupture.

  7. United Kingdom - Characterization of Landauer Microstar OSL Dosimetry System. Annex VI

    International Nuclear Information System (INIS)

    Austin, M.J.; Mayles, W.P.M.

    2013-01-01

    The commercial OSL system used in the CRP was investigated in terms of the dosimeter's early fading characteristic, the amount of stored dose lost per readout performed and the changeover between the two different stimulation light sources used to read low and high doses. It was found that 6 minutes must pass between irradiation and readout to allow for early fading of the OSL signal. Approximately 0.06% of the stored dose is lost per readout for dosimeters read out in the system's high dose mode. Finally, a steep transition was found in the OSL output when changing from one stimulation mode to the other. The system was found to be very simple and convenient to use, although reproducibility was found to be poor, and this was blamed on a possible mechanical problem with the dosimeter housing or the low power stimulation light that is used to read out dosimeters. (author)

  8. Hanford Tank Farms Waste Feed Flow Loop Phase VI: PulseEcho System Performance Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Denslow, Kayte M.; Bontha, Jagannadha R.; Adkins, Harold E.; Jenks, Jeromy WJ; Hopkins, Derek F.

    2012-11-21

    This document presents the visual and ultrasonic PulseEcho critical velocity test results obtained from the System Performance test campaign that was completed in September 2012 with the Remote Sampler Demonstration (RSD)/Waste Feed Flow Loop cold-test platform located at the Monarch test facility in Pasco, Washington. This report is intended to complement and accompany the report that will be developed by WRPS on the design of the System Performance simulant matrix, the analysis of the slurry test sample concentration and particle size distribution (PSD) data, and the design and construction of the RSD/Waste Feed Flow Loop cold-test platform.

  9. Molecular Characterization of a Functional Type VI Secretion System from a Clinical Isolate of Aeromonas hydrophilia

    Science.gov (United States)

    Our laboratory recently molecularly characterized the type II secretion system (T2SS)-associated cytotoxic enterotoxin (Act) and the T3SS-secreted AexU effector from a diarrheal isolate SSU of Aeromonas hydrophila. The role of these toxin proteins in the pathogenesis of A. hydrop...

  10. Molecular characterization of a functional type VI secretion system from a clinical isolate of Aeromonas hydrophila

    Science.gov (United States)

    Our laboratory recently molecularly characterized the type II secretion system (T2SS)-associated cytotoxic enterotoxin (Act) and the T3SS-secreted AexU effector from a diarrheal isolate SSU of Aeromonas hydrophila. The role of these toxin proteins in the pathogenesis of A. hydrop...

  11. Energy meshing techniques for processing ENDF/B-VI cross sections using the AMPX code system

    International Nuclear Information System (INIS)

    Dunn, M.E.; Greene, N.M.; Leal, L.C.

    1999-01-01

    Modern techniques for the establishment of criticality safety for fissile systems invariably require the use of neutronic transport codes with applicable cross-section data. Accurate cross-section data are essential for solving the Boltzmann Transport Equation for fissile systems. In the absence of applicable critical experimental data, the use of independent calculational methods is crucial for the establishment of subcritical limits. Moreover, there are various independent modern transport codes available to the criticality safety analyst (e.g., KENO V.a., MCNP, and MONK). In contrast, there is currently only one complete software package that processes data from the Version 6 format of the Evaluated Nuclear Data File (ENDF) to a format useable by criticality safety codes. To facilitate independent cross-section processing, Oak Ridge National Laboratory (ORNL) is upgrading the AMPX code system to enable independent processing of Version 6 formats using state-of-the-art procedures. The AMPX code system has been in continuous use at ORNL since the early 1970s and is the premier processor for providing multigroup cross sections for criticality safety analysis codes. Within the AMPX system, the module POLIDENT is used to access the resonance parameters in File 2 of an ENDF/B library, generate point cross-section data, and combine the cross sections with File 3 point data. At the heart of any point cross-section processing code is the generation of a suitable energy mesh for representing the data. The purpose of this work is to facilitate the AMPX upgrade through the development of a new and innovative energy meshing technique for processing point cross-section data

  12. Separation and concentration of uranium by extraction chromatography : U(VI) - H3PO4 system

    International Nuclear Information System (INIS)

    Nobre, J.S.M.

    1981-01-01

    The feasibility of using the extraction chromatographic technique as a way to recover uranium from phosphatic rocks evaluated. The behaviour of uranium from raw phsophoric acid solutions in chromatographic systems using the mixture di(2-ethylhexyl) orthophosphoric acid (D2EHPA) - tributyl phosphate (TBP) as the stationary phase was studied. Materials as alumina, activated carbon and the macroporous resins XAD-4 and XAD-7 were used as supports for organic stationary phase. The best results were obtained with poliacrilic polymer XAD-7, due to its excellent chromatographic properties and efficient organic phase retention. Uranium was quantitatively retained by D2EHPA-TBP-XAD-7 columns from synthetic phosphoric acid solutions with typical composition of phosphatic acid liquors. The elution of uranium from this system was also studied, and the best results were obtained with phosphoric acid solutions. This chromatographic column presented a high stability, not changing their properties even after more than twenty cycles, including the conditioning, sorption, wasking and elution steps. Uranium determinations were perfpormed by indirect titration with potassium dichromate and by molecular absorption spectrophotometry with hydrogen peroxide- carbonate. A new and more sensitive method for uranium determination in phosphoric medium, which might be applied to acid liquors of phosphatic ores, was developed. An extraction-photometric method was used, with Arsenazo III (1,8-dihydroxynaphtalene-3,6-disulphonic acid-2,7-bis(azo-2)-phenylarsonic acid) as the reagent for uranium. (Author) [pt

  13. 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....

  14. 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.

  15. Tank Waste Remediation System, Hanford Site, Richland, Washington. Final Environmental Impact Statement. Volume VI

    International Nuclear Information System (INIS)

    1996-08-01

    The U.S. Department Of Energy and the Washington State Department of Ecology added Appendix L (Volume 6), Response to Public Comments, to the Tank Waste Remediation System (TWRS) Final Environmental Impact Statement (EIS) for the Hanford Site, Richland, Washington, to fully address and respond to public comments on the Draft EIS. In addition, DOE considered public comments, along with other factors such as programmatic need, short- and long-term impacts, technical feasibility, and cost, in arriving at DOE's preferred alternative. During the public comment period for the Draft EIS, more than 350 individuals, agencies, Tribal Nations, and organizations provided comments. This volume represents a broad spectrum of private citizens; businesses; local, State, and Federal officials; Tribal Nations; and public interest groups

  16. Simultaneous removal of Cr(VI) and phenol contaminants using Z-scheme bismuth oxyiodide/reduced graphene oxide/bismuth sulfide system under visible-light irradiation.

    Science.gov (United States)

    Chen, Acong; Bian, Zhaoyong; Xu, Jie; Xin, Xin; Wang, Hui

    2017-12-01

    An all-solid-state Z-scheme system containing Bi-based semiconductors bismuth oxyiodide (BiOI) and bismuth sulfide (Bi 2 S 3 ) was constructed on reduced graphene oxide (rGO) sheets through an electrostatic self-assembly method to simultaneously remove aqueous Cr(VI) and phenol. In this Z-scheme that mimicked natural photosynthesis, photoinduced electrons in the conduction band (CB) of BiOI were transferred through rGO and reacted with photoinduced holes in the valence band (VB) of Bi 2 S 3 , which significantly increased its photocatalytic activity. The reduction and oxidation reactions were performed on Bi 2 S 3 and BiOI photocatalysts, respectively. Furthermore, complex contaminants of coexisting heavy metal Cr(VI) and organic phenol were treated using the system under visible-light irradiation. Results showed that Cr(VI) reduction and phenol oxidation were achieved efficiently with optimum reductive and oxidative efficiencies up to 73% and 95% under visible-light irradiation, respectively. This work provided a promising method of simultaneously removing heavy metals and organic pollutants by using a Z-scheme system with enhanced photocatalytic activity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Liquid-liquid extraction of uranium(VI) in the system with a membrane contactor.

    Science.gov (United States)

    Biełuszka, Paweł; Zakrzewska, Grażyna; Chajduk, Ewelina; Dudek, Jakub

    Raising role of the nuclear power industry, including governmental plans for the construction of first nuclear power plant in Poland, creates increasing demand for the uranium-based nuclear fuels. The project implemented by Institute of Nuclear Chemistry and Technology concerns the development of effective methods for uranium extraction from low-grade ores and phosphorites for production of yellow cake-U 3 O 8 . The Liqui-Cel ® Extra-Flow 2.5 × 8 Membrane Contactor produced by CELGARD LLC (Charlotte, NC) company is the main component of the installation for liquid-liquid extraction applied for processing of post leaching liquors. In the process of membrane extraction the uranyl ions from aqueous phase are transported through the membrane into organic phase. The flow of two phases in the system was arranged in co-current mode. The very important element of the work was a selection of extracting agents appropriate for the membrane process. After preliminary experiments comprising tests of membrane resistivity and determination of extraction efficiency, di(2-ethylhexyl)phosphoric acid was found to be most favourable. An important aspect of the work was the adjustment of hydrodynamic conditions in the capillary module. To avoid the membrane wettability by organic solvent and mixing two phases equal pressure drops along the membrane module to minimize the transmembrane pressure, were assumed. Determination of pressure drop along the module was conducted using Bernoulli equation. The integrated process of extraction/re-extraction conducted in continuous mode with application of two contactors was designed.

  18. Population inversion and gain calculations for 4p54d-4p55p and 4p55s - 4p55p Kr-like transitions in Y IV, Zr V, Nb VI and Mo VII

    International Nuclear Information System (INIS)

    Fournier, K.B.; Goldstein, W.H.; Stutman, D.; Finkenthal, M.; Soukhanovskii, V.; May, M.J.

    1999-01-01

    We present calculations of the quasi-steady state gain coefficient for the 4p 5 4d 1 P-4p 5 5p 1/2[1/2] 0 transition in Kr-like Y IV, Zr V, Nb VI and Mo VII ions. Gain coefficients which can lead to FUV-VUV (∝260 to 60 nm) lasing are found in all ions. Large gain coefficients are found for each ion at temperatures in excess of the ion's equilibrium temperature; realizing lasing in these systems will require a transient excitation mechanism. The density at which the maximal gain coefficient obtains increases for increasing ionization state. The 4p 5 5s 1/2[1/2] 1 -4p 5 5p 1/2[1/2] 0 and 4p 5 5s 3/2[3/2] 1 -4p 5 5p 1/2[1/2] 0 transitions also show population inversion and modest gain coefficients. Attractive features of these ions as potential lasents are the large ratio between the energy of the lasing transition and the excitation energy of the upper level of the lasing transition as well as the case with which they are produced in a low temperature, table-top scale plasma source. (orig.)

  19. Cell density- and quorum sensing-dependent expression of type VI secretion system 2 in Vibrio parahaemolyticus.

    Directory of Open Access Journals (Sweden)

    Li Wang

    Full Text Available BACKGROUND: Vibrio parahaemolyticus AphA and OpaR are the two master quorum sensing (QS regulators that are abundantly expressed at low cell density (LCD and high cell density (HCD, respectively, with a feature of reciprocally gradient production of them with transition between LCD and HCD. The type VI secretion system 2 (T6SS2 gene cluster can be assigned into three putative operons, namely VPA1027-1024, VPA1043-1028, and VPA1044-1046. T6SS2 contributes to adhesion of V. parahaemolyticus to host cells. METHODOLOGY/PRINCIPAL FINDINGS: OpaR box-like sequences were found within the upstream promoter regions of all the above three operons, while none of AphA box-like elements could be identified for them. The subsequent primer extension, LacZ fusion, electrophoretic mobility shift, and DNase I footprinting assays disclosed that OpaR bound to the promoter regions of these three operons to stimulate their transcription, while AphA negatively regulated their transcription most likely through acting on OpaR. This regulation led to a gradient increase of T6SS2 transcription with transition from LCD to HCD. CONCLUSIONS/SIGNIFICANCE: V. parahaemolyticus OpaR and AphA positively and negatively regulate T6SS2 expression, respectively, leading to a gradient elevation of T6SS2 expression with transition from LCD to HCD. T6SS2 genes are thus assigned as the QS regulon members in V. parahaemolyticus.

  20. Explorations of new phases in the Ga(III)/In(III)-Mo(VI)-Se(IV)/Te(IV)-O systems.

    Science.gov (United States)

    Kong, Fang; Hu, Chun-Li; Hu, Ting; Zhou, Yong; Mao, Jiang-Gao

    2009-07-07

    Systematic explorations of new phases in the Ga(III)/In(III)-Mo(VI)-Se(IV)/Te(IV)-O systems by hydrothermal syntheses or solid-state reactions at high-temperature led to four new quaternary compounds, namely, Ga(2)MoQ(2)O(10) (Q = Se, Te), In(2)Mo(2)Se(2)O(13)(H(2)O) and In(2)MoTe(2)O(10). Ga(2)MoQ(2)O(10) (Q = Se, Te) are isostructural and their structures feature a 3D network of gallium selenite/tellurite with 12-member ring tunnels along b-axis, the distorted MoO(6) octahedra are attached on the wall of the above tunnels. The structure of In(2)Mo(2)Se(2)O(13)(H(2)O) features a new pillared-layered architecture composed of 2D indium(III) selenite layers that are interconnected by Mo(2)O(10) dimers, forming 8-membered ring tunnels along the b-axis. The structure of In(2)MoTe(2)O(10) features a 2D indium oxide layer formed by corner- and edge-sharing InO(6) and InO(7) polyhedra with MoO(4) tetrahedra and TeO(n) (n = 4, 5) polyhedra hanging on both sides of the layer, there are weak interlayer Te-O bonds of 2.512 A. Results of optical diffuse reflectance spectrum measurements indicate that all four compounds are insulators, which are in agreement with results of band structure calculations based on DFT methods.

  1. Diverse toxic effectors are harbored by vgrG islands for interbacterial antagonism in type VI secretion system.

    Science.gov (United States)

    Ma, Jiale; Sun, Min; Pan, Zihao; Lu, Chengping; Yao, Huochun

    2018-04-16

    The type VI secretion system (T6SS) is considered as one of the key competition strategies by injecting toxic effectors for intestinal pathogens to acquire optimal colonization in host gut, a microenviroment with high-density polymicrobial community where bacteria compete for niches and resources. Enterotoxigenic Escherichia coli (ETEC), a major cause of infectious diarrhea in human and animals, widely encode T6SS clusters in their genomes. In this report, we first identified VT1, a novel amidase effector in ETEC, significantly hydrolyzed D-lactyl-L-Ala crosslinks between N-acetylmuramoyl and L-Ala in peptidoglycan. Further study showed that the VT1/VTI1 effector/immunity pair is encoded within a typical vgrG island, and plays a critical role for the successful establishment of ETEC in host gut. Numerous putative effectors with diverse toxin domains were found by retrieving vgrG islands in pathogenic E. coli, and designated as VT modules. Therein, VT5, a lysozyme-like effector widely encoded in ETEC, was confirmed to effectively kill adjacent cells, suggesting that VT toxin modules may be critical for pathogenic E. coli to seize a significantly competitive advantage for optimal intestinal colonization. To expand our analyses for large-scale search of VT antibacterial effectors based on vgrG island, >200 predicted effectors from 20 bacterial species were found and classified into 11 predicted toxins. This work reports a new retrieval strategy for screening T6SS effectors, and provides an example how pathogenic bacteria antagonize and displace commensal microbiome to successfully colonize in the host niches through a T6SS-dependent manner. Copyright © 2018. Published by Elsevier B.V.

  2. Analysing Scenarios of Cell Population System Development

    Directory of Open Access Journals (Sweden)

    M. S. Vinogradova

    2014-01-01

    Full Text Available The article considers an isolated population system consisting of two types of human stem cells, namely normal cells and cells with chromosomal abnormalities (abnormal ones. The system develops in the laboratory (in vitro. The article analyses possible scenarios of the population system development, which are implemented for different values of its parameters. An investigated model of the cell population system takes into account the limited resources. It is represented as a system of two nonlinear differential equations with continuous right-hand part. The model is considered with non-negative values of the variables; the domain is divided into four sets. The model feature is that in each set the right part of the system of differential equations has a different form.The article analyses a quality of the rest points of the system in each of four sets. The analytical conditions for determination of the number of rest points and the quality of rest points, with, at least, one zero coordinate, are obtained.It is shown that the population system under study cannot have more than two points of rest, both coordinates of which are positive (non-zero. It is difficult to determine quality of such rest points depending on the model parameters due to the complexity of the expressions, which define the systems of the first approximation, recorded in a neighborhood of these points of rest. Numerical research results of the stability of these points of rest are obtained, and phase portraits with the specified specific values of the system parameters are demonstrated. The main scenarios for the cell population development are adduced. Analysis of mathematical model shows that a cell population system may remain the system consisting of populations of normal and abnormal cells; it can degenerate into a population of abnormal cells or perish. The scenario, in which there is only the population of normal cells, is not implemented. The numerical simulation

  3. 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

    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...

  4. Ultratrace Determination of Cr(VI and Pb(II by Microsample Injection System Flame Atomic Spectroscopy in Drinking Water and Treated and Untreated Industrial Effluents

    Directory of Open Access Journals (Sweden)

    Jameel Ahmed Baig

    2013-01-01

    Full Text Available Simple and robust analytical procedures were developed for hexavalent chromium (Cr(VI and lead (Pb(II by dispersive liquid-liquid microextraction (DLLME using microsample injection system coupled with flame atomic absorption spectrophotometry (MIS-FAAS. For the current study, ammonium pyrrolidine dithiocarbamate (APDC, carbon tetrachloride, and ethanol were used as chelating agent, extraction solvent, and disperser solvent, respectively. The effective variables of developed method have been optimized and studied in detail. The limit of detection of Cr(VI and Pb(II were 0.037 and 0.054 µg/L, respectively. The enrichment factors in both cases were 400 with 40 mL of initial volumes. The relative standard deviations (RSDs, were 96%. The proposed method was successfully applied to the determination of Cr(VI and Pb(II at ultratrace levels in natural drinking water and industrial effluents wastewater of Denizli. Moreover, the proposed method was compared with the literature reported method.

  5. Cr(VI) and azo dye removal using a hollow-fibre membrane system functionalized with a biogenic Pd-magnetite catalyst.

    Science.gov (United States)

    Coker, V S; Garrity, A; Wennekes, W B; Roesink, H D W; Cutting, R S; Lloyd, J R

    2014-01-01

    This study investigates the application of a hybrid system combining hollow-fibre membrane technology with the reductive abilities of magnetic nanoparticles for the remediation of toxic Cr(VI) and the azo dye, Remazol Black B. Nano-scale biogenic magnetite (Fe3O4), formed by microbial reduction of the mineral ferrihydrite, has a high reductive capacity due to the presence of Fe(II) in the mineral structure. The magnetic nanoparticles (approximately 20 nm) can be arrayed with Pd0 nanoparticles (approximately 5 nm) making a catalytically active nanomaterial. Membrane units, with and without nanoparticles, were challenged with either Cr(VI) or azo dye and some were supplemented with sodium formate, as an electron donor for contaminant reduction promoted by the Pd. The combination of Pd-magnetite with formate resulted in the most effective remediation strategy for both contaminants and the lifetime of the membrane unit was also increased, with 55% (19 days) and 70% (23 days) removal of the azo dye and Cr(VI), respectively. Low flow rates of 0.1 ml/min resulted in improved efficiencies due to increased contact time with the membrane/nanoparticle unit, with 70-75% removal of each contaminant. Chemical analyses of the nanoparticles post-exposure to Cr(VI) in the membrane modules indicated Pd to be more oxidized when Cr removal was maximized, and that the Cr was partially reduced to Cr(III) at the surface of the magnetite. These results have demonstrated that hollow-fibre membrane units can be enhanced for the removal of soluble, redox sensitive contaminants by incorporation of a layer of palladized biogenic nanoparticulate magnetite.

  6. Campylobacter jejuni type VI secretion system: roles in adaptation to deoxycholic acid, host cell adherence, invasion, and in vivo colonization.

    Directory of Open Access Journals (Sweden)

    Kvin Lertpiriyapong

    Full Text Available The recently identified type VI secretion system (T6SS of proteobacteria has been shown to promote pathogenicity, competitive advantage over competing microorganisms, and adaptation to environmental perturbation. By detailed phenotypic characterization of loss-of-function mutants, in silico, in vitro and in vivo analyses, we provide evidence that the enteric pathogen, Campylobacter jejuni, possesses a functional T6SS and that the secretion system exerts pleiotropic effects on two crucial processes--survival in a bile salt, deoxycholic acid (DCA, and host cell adherence and invasion. The expression of T6SS during initial exposure to the upper range of physiological levels of DCA (0.075%-0.2% was detrimental to C. jejuni proliferation, whereas down-regulation or inactivation of T6SS enabled C. jejuni to resist this effect. The C. jejuni multidrug efflux transporter gene, cmeA, was significantly up-regulated during the initial exposure to DCA in the wild type C. jejuni relative to the T6SS-deficient strains, suggesting that inhibition of proliferation is the consequence of T6SS-mediated DCA influx. A sequential modulation of the efflux transporter activity and the T6SS represents, in part, an adaptive mechanism for C. jejuni to overcome this inhibitory effect, thereby ensuring its survival. C. jejuni T6SS plays important roles in host cell adhesion and invasion as T6SS inactivation resulted in a reduction of adherence to and invasion of in vitro cell lines, while over-expression of a hemolysin co-regulated protein, which encodes a secreted T6SS component, greatly enhanced these processes. When inoculated into B6.129P2-IL-10(tm1Cgn mice, the T6SS-deficient C. jejuni strains did not effectively establish persistent colonization, indicating that T6SS contributes to colonization in vivo. Taken together, our data demonstrate the importance of bacterial T6SS in host cell adhesion, invasion, colonization and, for the first time to our knowledge

  7. to Cr (VI)

    African Journals Online (AJOL)

    Michael Horsfall

    been held responsible for the major influx of Cr to the biosphere, accounting for 40% of the total industrial use (Barnhart, 1997). Out of the different variable valance states of Chromium, Cr(VI) and. Cr(III) are most stable; Cr(VI) owing to filled and. Cr(III) due to half filled orbital stability. Cr(VI) is extremely labile in the biological ...

  8. 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

  9. Study of the characteristic response of the pressure control system for the design parameters of the new turbine control system, MARK VI, in Cofrentes Nuclear Power Plant; Resultados del estudio de la respuesta caracteristica del sistema de control de presion para el Proyecto OCP-4300 Nuevo Sistema de Control de Turbina MARK VI en la C.N. Cofrentes

    Energy Technology Data Exchange (ETDEWEB)

    Palomo anaya, M. J.; Ruiz Bueno, G.; Mora, J. A.; Vaquer, J. I.; Bucho, L.; Lopez, B.

    2010-07-01

    This paper presents the results of the study of the characteristic response of the ancient Pressure and Turbine Control System for the OCP-4300 Project in the Cofrentes Nuclear Power Plant, made by Titania Servicios Tecnologicos in collaboration with the Institute for Industrial, Radiophysical and Environmental Safety. This work was done as one of the preliminary work necessary for replacing the old control system by Mark VI.

  10. Enzymatic reduction of U(VI) in groundwaters

    International Nuclear Information System (INIS)

    Addelouas, A.; Gong, W.; Lutze, W.; Nuttall, E.; Fritz, B.; Crovisier, J.L.

    1999-01-01

    The use of enzymatic reduction of U(VI) in remediation of groundwater contaminated with U(VI) is receiving considerable attention. Certain strains of bacteria can combine the oxidation of an organic compound to the reduction of U(VI) to U(IV), which precipitates as uraninite. In the present study, we tested the reduction of U(VI) in groundwaters with various origins and compositions. In all groundwaters u(VI) was reduced by sulfate reducing bacteria that had been activated by ethanol and tri-metaphosphate. The reduction rate of U(VI) depends on sulfate concentration in water and the abundance of bacteria in the system. This work shows that bacteria capable of U(VI) reduction are ubiquitous in nature, and suggests the possibility of a large application of the enzymatic reduction of U(VI) for in situ clean up of groundwaters contaminated with uranium. (authors)

  11. Clinically acceptable agreement between the ViMove wireless motion sensor system and the Vicon motion capture system when measuring lumbar region inclination motion in the sagittal and coronal planes

    DEFF Research Database (Denmark)

    Mjøsund, Hanne Leirbekk; Boyle, Eleanor; Kjær, Per

    2017-01-01

    . CONCLUSIONS: We found a clinically acceptable level of agreement between these two methods for measuring standing lumbar inclination motion in these two cardinal movement planes. Further research should investigate the ViMove system's ability to measure lumbar motion in more complex 3D functional movements...

  12. Enzymatic reduction of U(VI) in groundwaters; Reduction enzymatique de U(VI) dans des eaux souterraines

    Energy Technology Data Exchange (ETDEWEB)

    Addelouas, A.; Gong, W. [Center for Radioactive Waste Management, Advanced Materials Laboratory, 1001 University, Albuquerque (United States); Lutze, W.; Nuttall, E. [New Mexico Univ., Albuquerque, NM (United States). Dept. of Chemical and Nuclear Engineering; Fritz, B.; Crovisier, J.L. [Centre National de la Recherche Scientifique (CNRS), 67 - Strasbourg (France). Centre de Sedimentologie et Geochimie de la Surface

    1999-03-01

    The use of enzymatic reduction of U(VI) in remediation of groundwater contaminated with U(VI) is receiving considerable attention. Certain strains of bacteria can combine the oxidation of an organic compound to the reduction of U(VI) to U(IV), which precipitates as uraninite. In the present study, we tested the reduction of U(VI) in groundwaters with various origins and compositions. In all groundwaters u(VI) was reduced by sulfate reducing bacteria that had been activated by ethanol and tri-metaphosphate. The reduction rate of U(VI) depends on sulfate concentration in water and the abundance of bacteria in the system. This work shows that bacteria capable of U(VI) reduction are ubiquitous in nature, and suggests the possibility of a large application of the enzymatic reduction of U(VI) for in situ clean up of groundwaters contaminated with uranium. (authors) 12 refs.

  13. Electrochemistry and Spectroelectrochemistry of the Pu (III/IV) and (IV/VI) Couples in Nitric Acid Systems

    Energy Technology Data Exchange (ETDEWEB)

    Lines, Amanda M. [Nuclear Chemistry and Engineering, Pacific Northwest National Laboratory, Richland WA 99352; Adami, Susan R. [Nuclear Chemistry and Engineering, Pacific Northwest National Laboratory, Richland WA 99352; Casella, Amanda J. [Nuclear Chemistry and Engineering, Pacific Northwest National Laboratory, Richland WA 99352; Sinkov, Sergey I. [Nuclear Chemistry and Engineering, Pacific Northwest National Laboratory, Richland WA 99352; Lumetta, Gregg J. [Nuclear Chemistry and Engineering, Pacific Northwest National Laboratory, Richland WA 99352; Bryan, Samuel A. [Nuclear Chemistry and Engineering, Pacific Northwest National Laboratory, Richland WA 99352

    2017-09-20

    The solution chemistry of Pu in nitric acid is explored via electrochemistry and spectroelectrochemistry. By utilizing and comparing these techniques, an improved understanding of Pu behavior and its dependence on nitric acid concentration can be achieved. Here the Pu (III/IV) couple is characterized using cyclic voltammetry, square wave voltammetry, and a spectroelectrochemical Nernst step. Results indicate the formal reduction potential of the couple shifts negative with increasing acid concentration and reversible electrochemistry is no longer attainable above 6 M HNO3. Spectroelectrochemistry is also used to explore the irreversible oxidation of Pu(IV) to Pu(VI) and shine light on the mechanism and acid dependence of the redox reaction.

  14. Interactive effects of sulfur and chromium on antioxidative defense systems and BnMP1 gene expression in canola (Brassica napus L.) cultivars differing in Cr(VI) tolerance.

    Science.gov (United States)

    Terzi, Hakan; Yıldız, Mustafa

    2015-07-01

    Plants suffer with combined stress of sulfur (S) deficiency and hexavalent chromium [Cr(VI)] in soils. There are a few reports on the interactive effects of S-deficiency and Cr(VI) stress. Therefore, the interactions between S nutrition and Cr(VI) stress were investigated in hydroponically grown canola (Brassica napus L.) cultivars differing in Cr(VI) tolerance. The relatively Cr(VI)-tolerant (NK Petrol) and Cr(VI)-susceptible (Sary) cultivars were grown in S-sufficient nutrient solution and then exposed to variable S concentrations [deficient (0 mM S, -S) and sufficient (1 mM S, +S)]. The seedlings were then exposed to 100 μM Cr(VI) for 3 days. S-deficiency (-S/-Cr) and combined stress (-S/+Cr) caused a significant decrease in growth parameters of Sary than NK Petrol (P < 0.05). In -S/+Cr treatment, Cr accumulation in Sary was significantly higher than NK Petrol. The higher level of Cr in Sary increased lipid peroxidation and decreased chlorophyll content. The activities of antioxidant enzymes and cysteine content were significantly higher in NK Petrol than in Sary under combined stress. The levels of ascorbate (AsA) and glutathione (GSH) were significantly decreased by S deficiency. The expression level of metallothionein gene (BnMP1) in the tolerant NK Petrol was increased by -S/+Cr treatment. However, expression level of BnMP1 gene in the susceptible Sary was enhanced by +S/+Cr treatment. This result suggests metallothionein (MT) may be involved in Cr(VI) tolerance under S-deficient condition. In conclusion, S nutrition influenced Cr accumulation and enhanced tolerance caused by a positive effect on defense systems and gene expression.

  15. Delay differential systems for tick population dynamics.

    Science.gov (United States)

    Fan, Guihong; Thieme, Horst R; Zhu, Huaiping

    2015-11-01

    Ticks play a critical role as vectors in the transmission and spread of Lyme disease, an emerging infectious disease which can cause severe illness in humans or animals. To understand the transmission dynamics of Lyme disease and other tick-borne diseases, it is necessary to investigate the population dynamics of ticks. Here, we formulate a system of delay differential equations which models the stage structure of the tick population. Temperature can alter the length of time delays in each developmental stage, and so the time delays can vary geographically (and seasonally which we do not consider). We define the basic reproduction number [Formula: see text] of stage structured tick populations. The tick population is uniformly persistent if [Formula: see text] and dies out if [Formula: see text]. We present sufficient conditions under which the unique positive equilibrium point is globally asymptotically stable. In general, the positive equilibrium can be unstable and the system show oscillatory behavior. These oscillations are primarily due to negative feedback within the tick system, but can be enhanced by the time delays of the different developmental stages.

  16. EnViSoRS: Enhanced Vision System for Robotic Surgery. A User-Defined Safety Volume Tracking to Minimize the Risk of Intraoperative Bleeding

    Directory of Open Access Journals (Sweden)

    Veronica Penza

    2017-05-01

    Full Text Available In abdominal surgery, intraoperative bleeding is one of the major complications that affect the outcome of minimally invasive surgical procedures. One of the causes is attributed to accidental damages to arteries or veins, and one of the possible risk factors falls on the surgeon’s skills. This paper presents the development and application of an Enhanced Vision System for Robotic Surgery (EnViSoRS, based on a user-defined Safety Volume (SV tracking to minimize the risk of intraoperative bleeding. It aims at enhancing the surgeon’s capabilities by providing Augmented Reality (AR assistance toward the protection of vessels from injury during the execution of surgical procedures with a robot. The core of the framework consists in (i a hybrid tracking algorithm (LT-SAT tracker that robustly follows a user-defined Safety Area (SA in long term; (ii a dense soft tissue 3D reconstruction algorithm, necessary for the computation of the SV; (iii AR features for visualization of the SV to be protected and of a graphical gage indicating the current distance between the instruments and the reconstructed surface. EnViSoRS was integrated with a commercial robotic surgical system (the dVRK system for testing and validation. The experiments aimed at demonstrating the accuracy, robustness, performance, and usability of EnViSoRS during the execution of a simulated surgical task on a liver phantom. Results show an overall accuracy in accordance with surgical requirements (<5 mm, and high robustness in the computation of the SV in terms of precision and recall of its identification. The optimization strategy implemented to speed up the computational time is also described and evaluated, providing AR features update rate up to 4 fps, without impacting the real-time visualization of the stereo endoscopic video. Finally, qualitative results regarding the system usability indicate that the proposed system integrates well with the commercial surgical robot and

  17. The type VI secretion system encoded in SPI-6 plays a role in gastrointestinal colonization and systemic spread of Salmonella enterica serovar Typhimurium in the chicken.

    Directory of Open Access Journals (Sweden)

    David Pezoa

    Full Text Available The role of the Salmonella Pathogenicity Islands (SPIs in pathogenesis of Salmonella enterica Typhimurium infection in the chicken is poorly studied, while many studies have been completed in murine models. The Type VI Secretion System (T6SS is a recently described protein secretion system in Gram-negative bacteria. The genus Salmonella contains five phylogenetically distinct T6SS encoded in differentially distributed genomic islands. S. Typhimurium harbors a T6SS encoded in SPI-6 (T6SSSPI-6, which contributes to the ability of Salmonella to colonize mice. On the other hand, serotype Gallinarum harbors a T6SS encoded in SPI-19 (T6SSSPI-19 that is required for colonization of chicks. In this work, we investigated the role of T6SSSPI-6 in infection of chicks by S. Typhimurium. Oral infection of White Leghorn chicks showed that a ΔT6SSSPI-6 mutant had reduced colonization of the gut and internal organs, compared with the wild-type strain. Transfer of the intact T6SSSPI-6 gene cluster into the T6SS mutant restored bacterial colonization. In addition, our results showed that transfer of T6SSSPI-19 from S. Gallinarum to the ΔT6SSSPI-6 mutant of S. Typhimurium not only complemented the colonization defect but also resulted in a transient increase in the colonization of the cecum and ileum of chicks at days 1 and 3 post-infection. Our data indicates that T6SSSPI-6 contributes to chicken colonization and suggests that both T6SSSPI-6 and T6SSSPI-19 perform similar functions in vivo despite belonging to different phylogenetic families.

  18. Entry control system for large populations

    International Nuclear Information System (INIS)

    Merillat, P.D.

    1982-01-01

    An Entry Control System has been developed which is appropriate for use at an installation with a large population requiring access over a large area. This is accomplished by centralizing the data base management and enrollment functions and decentralizing the guard-assisted, positive personnel identification and access functions. Current information pertaining to all enrollees is maintained through user-friendly enrollment stations. These stations may be used to enroll individuals, alter their area access authorizations, change expiration dates, and other similar functions. An audit trail of data base alterations is provided to the System Manager. Decentrailized systems exist at each area to which access is controlled. The central system provides these systems with the necessary entry control information to allow them to operate microprocessor-driven entry control devices. The system is comprised of commercially available entry control components and is structured such that it will be able to incorporate improved devices as technology porogresses. Currently, access is granted to individuals who possess a valid credential, have current access authorization, can supply a memorized personal identification number, and whose physical hand dimensions match their profile obtained during enrollment. The entry control devices report misuses as security violations to a Guard Alarm Display and Assessment System

  19. Analysis of ZR-6 experiments using the KARATE-440 code system upgraded by ENDF/B-VI data

    International Nuclear Information System (INIS)

    Hegyi, Gy.; Kereszuri, A.; Maraczy, Cs.

    2002-01-01

    Extensive validation of nuclear libraries was performed against lattice experiments with the help of the MULTICELL lattice calculation code and the COREMICRO 2D fine diffusion code. New cross-section library set was developed for these codes based on the ENDF/B-VI nuclear database. These codes belong to the KARATE-440 code package which is used for the calculation of VVER-440 reactor cores. The ZR-6 zero power critical facility was used as experimental database, where a wide range of hexagonal lattices were investigated. In the first step single-pin-cell calculations were performed for uniform critical ZR-6 lattices, where the axial and radial leakage were taken into account by the measured material buckling. In this step beside of criticality some spectral indices were investigated too. In the second step 2D calculations were applied for all the experimental configurations, including different temperatures. The ∂ρ/∂Η and ∂ρ/∂Τ coefficients were evaluated, too.(author)

  20. Population Genetics of Identifiler System in Malaysia.

    Science.gov (United States)

    Nakamura, Yasutaka; Samejima, Michinaga; Minaguchi, Kiyoshi; Nambiar, Phrabhakaran

    2016-01-01

    Short tandem repeat (STR) polymorphisms were investigated in 341 unrelated Malay individuals (218 males and 123 females) living in or around Kuala Lumpur by using a forensic analysts kit. The following STRs were targeted: D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818, and FGA. The purpose of this study was to elucidate population genetics in Malaysia and calculate statistical parameters for forensic and anthropological research. Data on these STRs in the target population were obtained and subjected to statistical analysis. Accordance with the Hardy-Weinberg equilibrium was proven for all the loci targeted. The combined power of discrimination was greater than 0.9999999999, indicating that this multiplex system is an excellent tool for forensic casework. The allele frequency in the data were weighed against that in four other local populations (Chinese, Iranian, Belgian, and African). The average coefficient of correlation was strongest in the order of Africa (0.092522), Belgium (0.264822), Iran (0.404363), and China (0.706661). These results are consistent with what is known about the anthropological history of and prehistoric human migration in the Malay region. We believe that these data offer a valuable anthropological resource, being applicable to the statistical evaluation of DNA evidence in human identification, as well as the determination of ethnicity in healthy populations.

  1. Flutuação populacional de espécies de cigarrinhas transmissoras da clorose variegada dos citros (CVC em Viçosa-MG Population dynamics of sharpshooters species transmitter of citrus variegated chlorosis (CVC in Viçosa-MG

    Directory of Open Access Journals (Sweden)

    Dierlei dos Santos

    2005-08-01

    Full Text Available Os objetivos deste trabalho foram avaliar a presença e a dinâmica populacional, ao longo do ano, de cigarrinhas transmissoras da CVC, no município de Viçosa - MG. As coletas foram realizadas no período de agosto de 2003 a julho de 2004, com auxílio de armadilhas adesivas amarelas e com rede entomológica (puçá. Das onze espécies comprovadamente capazes de transmitir a CVC, foram encontradas nove. O número total de cigarrinhas capturadas foi de 2.966, sendo 2.805 nas armadilhas e 161 no puçá. As três espécies da família Cicadellidae mais expressivas em número de insetos foram Bucephalogonia xanthophis (36,6% capturados na rede entomológica e 34,7% na armadilha, Dilobopterus costalimai (9,9% capturados na rede entomológica e 11,3% na armadilha e Acrogonia citrina (6,8% capturados na rede entomológica e 7,4% na armadilha. No mês de novembro, foram coletadas 378 cigarrinhas, correspondendo ao mês de maior incidência, sendo que 292 dessas foram coletadas na primeira quinzena, concorrendo para um pico populacional. Não houve diferença significativa entre o número médio de cigarrinhas coletadas no interior e na periferia da área.The objectives of this work were to evaluate the presence and the population dynamics of Citrus CVC transmitter sharpshooters along the year in the municipality of Viçosa- MG. The sharpshooter populations were monitored in the period of August 2003 to July 2004 using yellow adhesive traps and entomologic nets. During this period 2966 sharpshooters were captured and identified. Among eleven species known as CVC transmitters, nine were found in the region. The three most expressive species in number found were Bucephalogonia xanthophis (36,6% captured in entomological net and 34,7% in the trap, Dilobopterus costalimai (9,9% captured in entomological net and 11,3% in the trap and Acrogonia citrina (6,8% captured in entomological net and 7,4% in the trap. The largest incidence of sharpshooters occurred

  2. and dioxouranium(vi)

    African Journals Online (AJOL)

    a

    solvent. The iodo complex appears to be a 1:2, while the perchlorato complex is 1:4 electrolyte. The uranyl(VI) complexes ..... Thermal analysis data thorium (IV) complexes of HNAAPTS. Decomposition temp. (oC). Weight loss (%). Complex. Initial. Final. Decomposition product. Theor. Exp. ThCl4.2(HNAAPTS). 240. 350.

  3. and dioxouranium(vi)

    African Journals Online (AJOL)

    a

    positive charge resulting from high oxidation state of central metal ion. Actinide ions generally present a high coordination number and the type of polyhedron obtainable is influenced by the nature of the coordinating ligands. Thorium(IV) and uranium(VI) with atomic radii of 1.65 and. 1.42 Å, respectively, and a high positive ...

  4. 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.

  5. The Hilbert series of N=1SO(N{sub c}) and Sp(N{sub c}) SQCD, Painleve VI and integrable systems

    Energy Technology Data Exchange (ETDEWEB)

    Basor, Estelle, E-mail: ebasor@aimath.or [American Institute of Mathematics, 360 Portage Avenue, Palo Alto, CA 9430 (United States); Chen Yang, E-mail: ychen@imperial.ac.uk [Department of Mathematics, Imperial College London, 180 Queen' s Gates, London SW7 2BZ (United Kingdom); Department of Mathematics, Faculty of Science and Technology, University of Macau, Av. Padre Tomas Pereira, Taipa, Macau (China); Mekareeya, Noppadol, E-mail: noppadol@mpp.mpg.de [Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, 80805 Muenchen (Germany)

    2012-07-21

    We present a novel approach for computing the Hilbert series of 4d N=1 supersymmetric QCD with SO(N{sub c}) and Sp(N{sub c}) gauge groups. It is shown that such Hilbert series can be recast in terms of determinants of Hankel matrices. With the aid of results from random matrix theory, such Hankel determinants can be evaluated both exactly and asymptotically. Several new results on Hilbert series for general numbers of colours and flavours are thus obtained in this paper. We show that the Hilbert series give rise to families of rational solutions, with palindromic numerators, to the Painleve VI equations. Due to the presence of such Painleve equations, there exist integrable Hamiltonian systems that describe the moduli spaces of SO(N{sub c}) and Sp(N{sub c}) SQCD. To each system, we explicitly state the corresponding Hamiltonian and family of elliptic curves. It turns out that such elliptic curves take the same form as the Seiberg-Witten curves for 4d N=2SU(2) gauge theory with 4 flavours.

  6. UVA1 for diffuse cutaneous systemic sclerosis in a Fitzpatrick skin type VI patient: outcomes in the modified Rodnan skin score

    Directory of Open Access Journals (Sweden)

    Bárbara Roque Ferreira

    2017-04-01

    Full Text Available Introduction: Cutaneous sclerosis can lead to important mobility impairment. Ultraviolet (UV A1 phototherapy may improve skin sclerosis, although most of the studies have been with Caucasian patients. Material and Methods: A 44-year-old patient, Fitzpatrick skin type VI, was being followed up with the diagnosis of diffuse cutaneous systemic sclerosis. He had significant mobility impairment, especially of the right hand and arm. In 2015 he started UVA1 phototherapy daily, Monday until Friday (Waldmann® 7001 UVA cabin equipped with 40 Philips TL/10R lamps − spectral irradiation between 340 and 400 nm. The initial dose was 10 J/cm2, rapidly increased up to a steady dose of 35 J/cm2. Results: After 40 sessions of UVA1, active fingers flexion and abduction of the right arm significantly improved and the modified Rodnan skin score changed from 26 to 11. Conclusion: The modified Rodnan skin score is a practical and useful tool during the follow-up of patients with systemic sclerosis. UVA1 phototherapy improves cutaneous sclerosis, and the related mobility impairment, and a dose of 35 J/cm2 is effective, even in higher phototypes, having a good safety profile.

  7. XI International conference Problems of solvation and complex formation in solutions, and VI Conference of young scientists Theoretical and experimental chemistry of liquid-phase systems (Krestovsky readings). Summary of reports

    International Nuclear Information System (INIS)

    2011-01-01

    The collection contains materials of plenary, sectional and poster sessions, presented at the XI International conference Problems of solvation and complex formation in solutions, and VI Conference of young scientists Theoretical and experimental chemistry of liquid-phase systems (Krestovsky readings). Theoretical questions and new experimental methods of chemistry of solutions, structure and dynamics of molecular and ion-molecular systems in solution and at the phase boundary; modern aspects of applied chemistry of solutions are discussed [ru

  8. 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...

  9. Extraction and separation of tungsten (VI) from aqueous media with Triton X-100-ammonium sulfate-water aqueous two-phase system without any extractant.

    Science.gov (United States)

    Yongqiang Zhang; Tichang Sun; Tieqiang Lu; Chunhuan Yan

    2016-11-25

    An aqueous two-phase system composed of Triton X-100-(NH 4 ) 2 SO 4 -H 2 O was proposed for extraction and separation of tungsten(VI) from aqueous solution without using any extractant. The effects of aqueous pH, concentration of ammonium sulfate, Triton X-100 and tungsten, extracting temperature on the extraction of tungsten were investigated. The extraction of tungsten has remarkable relationship with aqueous pH and are to above 90% at pH=1.0-3.0 under studied pH range (pH=1.0-7.0) and increases gradually with increasing Triton X-100 concentration, but decreases slightly with increasing ammonium sulfate concentration. The extraction percentage of tungsten is hardly relevant to temperature but its distribution coefficient linearly increases with increasing temperature within 303.15-343.15K. The distribution coefficient of tungsten increases with the increase of initial tungsten concentration (0.1-3%) and temperature (303.15 K-333.15K). The solubilization capacity of tungsten in Triton X-100 micellar phase is independent of temperature. FT-IR analysis reveals that there is no evident interaction between polytungstate anion and ether oxygen unit in Triton X-100, and DLS analysis indicates that zeta potential of Triton X-100 micellar phase have a little change from positive to negative after extracting tungsten. Based on the above-mentioned results, it can be deduced that polytungstate anions are solubilized in hydrophilic outer shell of Triton X-100 micelles by electrostatic attraction depending on its relatively high hydrophobic nature. The stripping of tungsten is mainly influenced by temperature and can be easily achieved to 95% in single stage stripping. The tungsten (VI) is separated out from solution containing Fe(III), Co(II), Ni(II), Cu(II), Zn(II), Al(III), Cr(III) and Mn(II) under the suitable conditions. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Synthesis, characterization and thermal study of Rb−U(IV)−Mo−O and Rb−U(VI)−Mo−O systems

    Energy Technology Data Exchange (ETDEWEB)

    Keskar, Meera, E-mail: mskeskar@barc.gov.in; Sali, S.K.; Krishnan, K.; Kannan, S.

    2016-09-15

    Four novel rubidium uranium (IV) molybdate compounds, Rb{sub 4}U{sub 5}(MoO{sub 4}){sub 12}, Rb{sub 2}U(MoO{sub 4}){sub 3}, Rb{sub 4}U(MoO{sub 4}){sub 4} and Rb{sub 8}U(MoO{sub 4}){sub 6} have been prepared by solid state route, reacting Rb{sub 2}MoO{sub 4}, UMoO{sub 5} and MoO{sub 3} in desired molar proportions in evacuated sealed quartz ampoules at 823 K and characterized by powder X-ray diffraction (XRD) and thermal analysis techniques. Thermal stability of the compounds was determined in helium atmosphere and oxidation behavior was studied in air using Thermogravimetric (TG) technique. The sub-solidus phase relations in Rb−U(VI)−Mo−O system were determined at 873 K in air. A pseudo-ternary phase diagram of Rb{sub 2}O−UO{sub 3}−MoO{sub 3} system was drawn on the basis of phase analysis of various phase mixtures prepared in Rb−U−Mo−O system and phase fields were established by powder X-ray diffraction. Rb{sub 2}UMo{sub 2}O{sub 10}, Rb{sub 6}UMo{sub 4}O{sub 18} and Rb{sub 2}U{sub 2}Mo{sub 3}O{sub 16} were identified during phase diagram study. Melting and thermal stability of these compounds were determined using differential thermal analysis (DTA) technique. - Highlights: • Synthesis of novel quaternary rubidium uranium (IV) molybdates by solid state route. • XRD analysis of the compounds. • Thermal stability in helium atmosphere and oxidation in air using TG/DTG/DTA technique. • Phase diagram of Rb−U−Mo−O system at 873 K.

  11. Diversity of Clinical and Environmental Isolates of Vibrio cholerae in Natural Transformation and Contact-Dependent Bacterial Killing Indicative of Type VI Secretion System Activity.

    Science.gov (United States)

    Bernardy, Eryn E; Turnsek, Maryann A; Wilson, Sarah K; Tarr, Cheryl L; Hammer, Brian K

    2016-05-01

    The bacterial pathogen Vibrio cholerae can occupy both the human gut and aquatic reservoirs, where it may colonize chitinous surfaces that induce the expression of factors for three phenotypes: chitin utilization, DNA uptake by natural transformation, and contact-dependent bacterial killing via a type VI secretion system (T6SS). In this study, we surveyed a diverse set of 53 isolates from different geographic locales collected over the past century from human clinical and environmental specimens for each phenotype outlined above. The set included pandemic isolates of serogroup O1, as well as several serogroup O139 and non-O1/non-O139 strains. We found that while chitin utilization was common, only 22.6% of the isolates tested were proficient at chitin-induced natural transformation, suggesting that transformation is expendable. Constitutive contact-dependent killing of Escherichia coli prey, which is indicative of a functional T6SS, was rare among clinical isolates (only 4 of 29) but common among environmental isolates (22 of 24). These results bolster the pathoadaptive model in which tight regulation of T6SS-mediated bacterial killing is beneficial in a human host, whereas constitutive killing by environmental isolates may give a competitive advantage in natural settings. Future sequence analysis of this set of diverse isolates may identify previously unknown regulators and structural components for both natural transformation and T6SS. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  12. Diversity of Clinical and Environmental Isolates of Vibrio cholerae in Natural Transformation and Contact-Dependent Bacterial Killing Indicative of Type VI Secretion System Activity

    Science.gov (United States)

    Bernardy, Eryn E.; Turnsek, Maryann A.; Wilson, Sarah K.; Tarr, Cheryl L.

    2016-01-01

    The bacterial pathogen Vibrio cholerae can occupy both the human gut and aquatic reservoirs, where it may colonize chitinous surfaces that induce the expression of factors for three phenotypes: chitin utilization, DNA uptake by natural transformation, and contact-dependent bacterial killing via a type VI secretion system (T6SS). In this study, we surveyed a diverse set of 53 isolates from different geographic locales collected over the past century from human clinical and environmental specimens for each phenotype outlined above. The set included pandemic isolates of serogroup O1, as well as several serogroup O139 and non-O1/non-O139 strains. We found that while chitin utilization was common, only 22.6% of the isolates tested were proficient at chitin-induced natural transformation, suggesting that transformation is expendable. Constitutive contact-dependent killing of Escherichia coli prey, which is indicative of a functional T6SS, was rare among clinical isolates (only 4 of 29) but common among environmental isolates (22 of 24). These results bolster the pathoadaptive model in which tight regulation of T6SS-mediated bacterial killing is beneficial in a human host, whereas constitutive killing by environmental isolates may give a competitive advantage in natural settings. Future sequence analysis of this set of diverse isolates may identify previously unknown regulators and structural components for both natural transformation and T6SS. PMID:26944842

  13. Functional exploration of the bacterial type VI secretion system in mutualism: Azorhizobium caulinodans ORS571-Sesbania rostrata as a research model.

    Science.gov (United States)

    Lin, Hsiao-Han; Huang, Hsin-Mei; Yu, Manda; Lai, Erh-Min; Chien, Hsiao-Lin; Liu, Chi-Te

    2018-03-08

    The bacterial type VI secretion system (T6SS) has been considered the armed force of bacteria because it can deliver toxin effectors to prokaryotic or eukaryotic cells for survival and fitness. Although many legume symbiotic rhizobacteria encode T6SS in their genome, the biological function of T6SS in these bacteria is still unclear. To elucidate this issue, we used Azorhizobium caulinodans ORS571 and its symbiotic host Sesbania rostrata as our research model. By using T6SS gene deletion mutants, we found that T6SS provides A. caulinodans with better symbiotic competitiveness when co-infected with a T6SS-lacking strain, as demonstrated by two independent T6SS-deficient mutants. Meanwhile, the symbiotic effectiveness was not affected by T6SS because the nodule phenotype, nodule size, and nodule nitrogen fixation ability did not differ between the T6SS mutants and the wild-type when infected alone. Our data also suggest that under several lab culture conditions tested, A. caulinodans showed no T6SS-dependent interbacterial competition activity. Therefore, instead of being an antihost or antibacterial weapon of the bacterium, the T6SS in A. caulinodans ORS571 seems to participate specifically in symbiosis by increasing its symbiotic competitiveness.

  14. Energy balance of ENDF/B-VI

    International Nuclear Information System (INIS)

    MacFarlane, R.E.

    1994-01-01

    ENDF/B-VI through Release 2 has been tested for neutron-photon energy balance using the Heater module of the NJOY nuclear data procesing system. The situation is much improved over ENDF/B-V, but there are still a number of maerials that show problems

  15. 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

  16. Plant Mating Systems Often Vary Widely Among Populations

    Directory of Open Access Journals (Sweden)

    Michael R. Whitehead

    2018-04-01

    Full Text Available Most flowering plants are hermaphroditic, yet the proportion of seeds fertilized by self and outcross pollen varies widely among species, ranging from predominant self-fertilization to exclusive outcrossing. A population's rate of outcrossing has important evolutionary outcomes as it influences genetic structure, effective population size, and offspring fitness. Because most mating system studies have quantified outcrossing rates for just one or two populations, past reviews of mating system diversity have not been able to characterize the extent of variation among populations. Here we present a new database of more than 30 years of mating system studies that report outcrossing rates for three or more populations per species. This survey, which includes 741 populations from 105 species, illustrates substantial and prevalent among-population variation in the mating system. Intermediate outcrossing rates (mixed mating are common; 63% of species had at least one mixed mating population. The variance among populations and within species was not significantly correlated with pollination mode or phylogeny. Our review underscores the need for studies exploring variation in the relative influence of ecological and genetic factors on the mating system, and how this varies among populations. We conclude that estimates of outcrossing rates from single populations are often highly unreliable indicators of the mating system of an entire species.

  17. Evolution of Systemic Hypertension in Pakistani Population

    International Nuclear Information System (INIS)

    Aziz, K. U.

    2015-01-01

    The prevalence of essential hypertension is alarmingly increasing in Pakistani population inspite of the demographics being of lower BMI and nutrition. In this review, the possible factors responsible for this increase are identified by reviewing the population studies conducted in Pakistan. The prevalence rate is about 3 - 4% in childhood and steeply rises near the middle age. The factors peculiar to Pakistan were increased genetic susceptibility, environmental factors such as gender, females gender, urbanization, obesity and sedentary life styles particularly in middle age, cultural practices promoting sedentary life style in female. (author)

  18. 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...

  19. Mean Field Control of Large Population Stochastic Systems

    Science.gov (United States)

    2012-07-31

    Final Report July 2012 Mean Field Control of Large Population ...complexity of such large population stochastic dynamic systems, and frequently their inherent nature, make centralized control infeasible or... control ) is that when the agent population is very large individual feedback strategies exist for all of the agents so that each agent will be in an

  20. KENO-VI Primer: A Primer for Criticality Calculations with SCALE/KENO-VI Using GeeWiz

    Energy Technology Data Exchange (ETDEWEB)

    Bowman, Stephen M [ORNL

    2008-09-01

    The SCALE (Standardized Computer Analyses for Licensing Evaluation) computer software system developed at Oak Ridge National Laboratory is widely used and accepted around the world for criticality safety analyses. The well-known KENO-VI three-dimensional Monte Carlo criticality computer code is one of the primary criticality safety analysis tools in SCALE. The KENO-VI primer is designed to help a new user understand and use the SCALE/KENO-VI Monte Carlo code for nuclear criticality safety analyses. It assumes that the user has a college education in a technical field. There is no assumption of familiarity with Monte Carlo codes in general or with SCALE/KENO-VI in particular. The primer is designed to teach by example, with each example illustrating two or three features of SCALE/KENO-VI that are useful in criticality analyses. The primer is based on SCALE 6, which includes the Graphically Enhanced Editing Wizard (GeeWiz) Windows user interface. Each example uses GeeWiz to provide the framework for preparing input data and viewing output results. Starting with a Quickstart section, the primer gives an overview of the basic requirements for SCALE/KENO-VI input and allows the user to quickly run a simple criticality problem with SCALE/KENO-VI. The sections that follow Quickstart include a list of basic objectives at the beginning that identifies the goal of the section and the individual SCALE/KENO-VI features that are covered in detail in the sample problems in that section. Upon completion of the primer, a new user should be comfortable using GeeWiz to set up criticality problems in SCALE/KENO-VI. The primer provides a starting point for the criticality safety analyst who uses SCALE/KENO-VI. Complete descriptions are provided in the SCALE/KENO-VI manual. Although the primer is self-contained, it is intended as a companion volume to the SCALE/KENO-VI documentation. (The SCALE manual is provided on the SCALE installation DVD.) The primer provides specific examples of

  1. Whole genome sequencing and analysis of Campylobacter coli YH502 from retail chicken reveals a plasmid-borne type VI secretion system

    Directory of Open Access Journals (Sweden)

    Sandeep Ghatak

    2017-03-01

    Full Text Available Campylobacter is a major cause of foodborne illnesses worldwide. Campylobacter infections, commonly caused by ingestion of undercooked poultry and meat products, can lead to gastroenteritis and chronic reactive arthritis in humans. Whole genome sequencing (WGS is a powerful technology that provides comprehensive genetic information about bacteria and is increasingly being applied to study foodborne pathogens: e.g., evolution, epidemiology/outbreak investigation, and detection. Herein we report the complete genome sequence of Campylobacter coli strain YH502 isolated from retail chicken in the United States. WGS, de novo assembly, and annotation of the genome revealed a chromosome of 1,718,974 bp and a mega-plasmid (pCOS502 of 125,964 bp. GC content of the genome was 31.2% with 1931 coding sequences and 53 non-coding RNAs. Multiple virulence factors including a plasmid-borne type VI secretion system and antimicrobial resistance genes (beta-lactams, fluoroquinolones, and aminoglycoside were found. The presence of T6SS in a mobile genetic element (plasmid suggests plausible horizontal transfer of these virulence genes to other organisms. The C. coli YH502 genome also harbors CRISPR sequences and associated proteins. Phylogenetic analysis based on average nucleotide identity and single nucleotide polymorphisms identified closely related C. coli genomes available in the NCBI database. Taken together, the analyzed genomic data of this potentially virulent strain of C. coli will facilitate further understanding of this important foodborne pathogen most likely leading to better control strategies. The chromosome and plasmid sequences of C. coli YH502 have been deposited in GenBank under the accession numbers CP018900.1 and CP018901.1, respectively.

  2. Role of the Genes of Type VI Secretion System in Virulence of Rice Bacterial Brown Stripe Pathogen Acidovorax avenae subsp. avenae Strain RS-2

    Directory of Open Access Journals (Sweden)

    Md. Mahidul Islam Masum

    2017-09-01

    Full Text Available The Type VI secretion system (T6SS is a class of macromolecular machine that is required for the virulence of gram-negative bacteria. However, it is still not clear what the role of T6SS in the virulence of rice bacterial brown stripe pathogen Acidovorax avenae subsp. avenae (Aaa is. The aim of the current study was to investigate the contribution of T6SS in Aaa strain RS2 virulence using insertional deletion mutation and complementation approaches. This strain produced weak virulence but contains a complete T6SS gene cluster based on a genome-wide analysis. Here we compared the virulence-related phenotypes between the wild-type (RS-2 and 25 T6SS mutants, which were constructed using homologous recombination methods. The mutation of 15 T6SS genes significantly reduced bacterial virulence and the secretion of Hcp protein. Additionally, the complemented 7 mutations ΔpppA, ΔclpB, Δhcp, ΔdotU, ΔicmF, ΔimpJ, and ΔimpM caused similar virulence characteristics as RS-2. Moreover, the mutant ΔpppA, ΔclpB, ΔicmF, ΔimpJ and ΔimpM genes caused by a 38.3~56.4% reduction in biofilm formation while the mutants ΔpppA, ΔclpB, ΔicmF and Δhcp resulted in a 37.5~44.6% reduction in motility. All together, these results demonstrate that T6SS play vital roles in the virulence of strain RS-2, which may be partially attributed to the reductions in Hcp secretion, biofilm formation and motility. However, differences in virulence between strain RS-1 and RS-2 suggest that other factors may also be involved in the virulence of Aaa.

  3. Role of the Genes of Type VI Secretion System in Virulence of Rice Bacterial Brown Stripe Pathogen Acidovorax avenae subsp. avenae Strain RS-2.

    Science.gov (United States)

    Masum, Md Mahidul Islam; Yang, Yingzi; Li, Bin; Olaitan, Ogunyemi Solabomi; Chen, Jie; Zhang, Yang; Fang, Yushi; Qiu, Wen; Wang, Yanli; Sun, Guochang

    2017-09-21

    The Type VI secretion system (T6SS) is a class of macromolecular machine that is required for the virulence of gram-negative bacteria. However, it is still not clear what the role of T6SS in the virulence of rice bacterial brown stripe pathogen Acidovorax avenae subsp. avenae (Aaa) is. The aim of the current study was to investigate the contribution of T6SS in Aaa strain RS2 virulence using insertional deletion mutation and complementation approaches. This strain produced weak virulence but contains a complete T6SS gene cluster based on a genome-wide analysis. Here we compared the virulence-related phenotypes between the wild-type (RS-2) and 25 T6SS mutants, which were constructed using homologous recombination methods. The mutation of 15 T6SS genes significantly reduced bacterial virulence and the secretion of Hcp protein. Additionally, the complemented 7 mutations Δ pppA , Δ clpB , Δ hcp , Δ dotU , Δ icmF , Δ impJ , and Δ impM caused similar virulence characteristics as RS-2. Moreover, the mutant Δ pppA , Δ clpB , Δ icmF , Δ impJ and Δ impM genes caused by a 38.3~56.4% reduction in biofilm formation while the mutants Δ pppA , Δ clpB , Δ icmF and Δ hcp resulted in a 37.5~44.6% reduction in motility. All together, these results demonstrate that T6SS play vital roles in the virulence of strain RS-2, which may be partially attributed to the reductions in Hcp secretion, biofilm formation and motility. However, differences in virulence between strain RS-1 and RS-2 suggest that other factors may also be involved in the virulence of Aaa.

  4. A disordered region in the EvpP protein from the type VI secretion system of Edwardsiella tarda is essential for EvpC binding.

    Directory of Open Access Journals (Sweden)

    Wentao Hu

    Full Text Available The type VI secretion system (T6SS of pathogenic bacteria plays important roles in both virulence and inter-bacterial competitions. The effectors of T6SS are presumed to be transported either by attaching to the tip protein or by interacting with HcpI (haemolysin corregulated protein 1. In Edwardsiella tarda PPD130/91, the T6SS secreted protein EvpP (E. tarda virulent protein P is found to be essential for virulence and directly interacts with EvpC (Hcp-like, suggesting that it could be a potential effector. Using limited protease digestion, nuclear magnetic resonance heteronuclear Nuclear Overhauser Effects, and hydrogen-deuterium exchange mass spectrometry, we confirmed that the dimeric EvpP (40 kDa contains a substantial proportion (40% of disordered regions but still maintains an ordered and folded core domain. We show that an N-terminal, 10-kDa, protease-resistant fragment in EvpP connects to a shorter, 4-kDa protease-resistant fragment through a highly flexible region, which is followed by another disordered region at the C-terminus. Within this C-terminal disordered region, residues Pro143 to Ile168 are essential for its interaction with EvpC. Unlike the highly unfolded T3SS effector, which has a lower molecular weight and is maintained in an unfolded conformation with a dedicated chaperone, the T6SS effector seems to be relatively larger, folded but partially disordered and uses HcpI as a chaperone.

  5. THE MASS-LOSS RETURN FROM EVOLVED STARS TO THE LARGE MAGELLANIC CLOUD. VI. LUMINOSITIES AND MASS-LOSS RATES ON POPULATION SCALES

    International Nuclear Information System (INIS)

    Riebel, D.; Meixner, M.; Srinivasan, S.; Sargent, B.

    2012-01-01

    We present results from the first application of the Grid of Red Supergiant and Asymptotic Giant Branch ModelS (GRAMS) model grid to the entire evolved stellar population of the Large Magellanic Cloud (LMC). GRAMS is a pre-computed grid of 80,843 radiative transfer models of evolved stars and circumstellar dust shells composed of either silicate or carbonaceous dust. We fit GRAMS models to ∼30,000 asymptotic giant branch (AGB) and red supergiant (RSG) stars in the LMC, using 12 bands of photometry from the optical to the mid-infrared. Our published data set consists of thousands of evolved stars with individually determined evolutionary parameters such as luminosity and mass-loss rate. The GRAMS grid has a greater than 80% accuracy rate discriminating between oxygen- and carbon-rich chemistry. The global dust injection rate to the interstellar medium (ISM) of the LMC from RSGs and AGB stars is on the order of 2.1 × 10 –5 M ☉ yr –1 , equivalent to a total mass injection rate (including the gas) into the ISM of ∼6 × 10 –3 M ☉ yr –1 . Carbon stars inject two and a half times as much dust into the ISM as do O-rich AGB stars, but the same amount of mass. We determine a bolometric correction factor for C-rich AGB stars in the K s band as a function of J – K s color, BC K s = -0.40(J-K s ) 2 + 1.83(J-K s ) + 1.29. We determine several IR color proxies for the dust mass-loss rate (M-dot d ) from C-rich AGB stars, such as log M-dot d = (-18.90/((K s -[8.0])+3.37) - 5.93. We find that a larger fraction of AGB stars exhibiting the 'long-secondary period' phenomenon are more O-rich than stars dominated by radial pulsations, and AGB stars without detectable mass loss do not appear on either the first-overtone or fundamental-mode pulsation sequences.

  6. Acid-Induced Type VI Secretion System Is Regulated by ExoR-ChvG/ChvI Signaling Cascade in Agrobacterium tumefaciens

    Science.gov (United States)

    Shaw, Gwo-Chyuan; Lai, Erh-Min

    2012-01-01

    The type VI secretion system (T6SS) is a widespread, versatile protein secretion system in pathogenic Proteobacteria. Several T6SSs are tightly regulated by various regulatory systems at multiple levels. However, the signals and/or regulatory mechanisms of many T6SSs remain unexplored. Here, we report on an acid-induced regulatory mechanism activating T6SS in Agrobacterium tumefaciens, a plant pathogenic bacterium causing crown gall disease in a wide range of plants. We monitored the secretion of the T6SS hallmark protein hemolysin-coregulated protein (Hcp) from A. tumefaciens and found that acidity is a T6SS-inducible signal. Expression analysis of the T6SS gene cluster comprising the imp and hcp operons revealed that imp expression and Hcp secretion are barely detected in A. tumefaciens grown in neutral minimal medium but are highly induced with acidic medium. Loss- and gain-of-function analysis revealed that the A. tumefaciens T6SS is positively regulated by a chvG/chvI two-component system and negatively regulated by exoR. Further epistasis analysis revealed that exoR functions upstream of the chvG sensor kinase in regulating T6SS. ChvG protein levels are greatly increased in the exoR deletion mutant and the periplasmic form of overexpressed ExoR is rapidly degraded under acidic conditions. Importantly, ExoR represses ChvG by direct physical interaction, but disruption of the physical interaction allows ChvG to activate T6SS. The phospho-mimic but not wild-type ChvI response regulator can bind to the T6SS promoter region in vitro and activate T6SS with growth in neutral minimal medium. We present the first evidence of T6SS activation by an ExoR-ChvG/ChvI cascade and propose that acidity triggers ExoR degradation, thereby derepressing ChvG/ChvI to activate T6SS in A. tumefaciens. PMID:23028331

  7. T346Hunter: a novel web-based tool for the prediction of type III, type IV and type VI secretion systems in bacterial genomes.

    Directory of Open Access Journals (Sweden)

    Pedro Manuel Martínez-García

    Full Text Available T346Hunter (Type Three, Four and Six secretion system Hunter is a web-based tool for the identification and localisation of type III, type IV and type VI secretion systems (T3SS, T4SS and T6SS, respectively clusters in bacterial genomes. Non-flagellar T3SS (NF-T3SS and T6SS are complex molecular machines that deliver effector proteins from bacterial cells into the environment or into other eukaryotic or prokaryotic cells, with significant implications for pathogenesis of the strains encoding them. Meanwhile, T4SS is a more functionally diverse system, which is involved in not only effector translocation but also conjugation and DNA uptake/release. Development of control strategies against bacterial-mediated diseases requires genomic identification of the virulence arsenal of pathogenic bacteria, with T3SS, T4SS and T6SS being major determinants in this regard. Therefore, computational methods for systematic identification of these specialised machines are of particular interest. With the aim of facilitating this task, T346Hunter provides a user-friendly web-based tool for the prediction of T3SS, T4SS and T6SS clusters in newly sequenced bacterial genomes. After inspection of the available scientific literature, we constructed a database of hidden Markov model (HMM protein profiles and sequences representing the various components of T3SS, T4SS and T6SS. T346Hunter performs searches of such a database against user-supplied bacterial sequences and localises enriched regions in any of these three types of secretion systems. Moreover, through the T346Hunter server, users can visualise the predicted clusters obtained for approximately 1700 bacterial chromosomes and plasmids. T346Hunter offers great help to researchers in advancing their understanding of the biological mechanisms in which these sophisticated molecular machines are involved. T346Hunter is freely available at http://bacterial-virulence-factors.cbgp.upm.es/T346Hunter.

  8. Adsorção de cromo (VI por carvão ativado granular de soluções diluídas utilizando um sistema batelada sob pH controlado Chromium (VI adsorption by GAC from diluted solutions in batch system and controlled ph

    Directory of Open Access Journals (Sweden)

    Renata Santos Souza

    2009-09-01

    solutions, and batch systems with controlled pH. The functional groups on the CAG surface was carried out by the Boehm method. In addition, effect of pH on the Cr(VI adsorption, adsorption equilibrium, and kinetic were studied under experimental conditions (pH = 6, MA = 6g, for 90min.. On the GAC surface, carboxylic groups were found to be in higher concentrations (MAS=0,43 mmol/gCAG, which increase the Cr(VI adsorption, principally in acidic pH values. The adsorption capacity is dependent on the pH of the solution, due to its influence on the surface properties of the CAG and different ionic forms of the Cr(VI solutions. The adsorption equilibrium data was adjusted satisfactorily by the Langmuir isotherm (R²=0,988, favorable type. From kinetics adsorption of 20 mg/L and 5 mg/L, the results were compatible with the national legislation (Res. nº 357/05. Therefore, the experimental system using (CAG was efficient in removing the Cr(VI from liquid streams containing low concentrations of the metal.

  9. Geodemography: Land cover, geographical information systems and population distribution

    Directory of Open Access Journals (Sweden)

    Francisco J. Goerlich Gisbert

    2013-01-01

    Full Text Available This paper examines the recent application of the Geographical Information Systems (GIS to the analysis of population distribution. We mention the efforts of the National Statistical Institutes in this direction boosted by the last census 2011.The stating point is a growing need to have available population figures for areas not related to administrative boundaries, either user defined zones or in grid format.This allows a convenient zonal system to combine demographic characteristics with environmental and pure geographic data, so the relation between the man and the environment can be analyzed in a unified way.Eventually, we offer a practical illustration of the interactions between GIS techniques and administrative population data in the study of spatial population distribution: We build a density grid for Spain by dasymetric methods from census tracts population data and Land Cover and Use Information System of Spain (SIOSE.The analysis is done within the spatial reference framework of the European Union.

  10. Effectiveness of a Wii balance board-based system (eBaViR) for balance rehabilitation: a pilot randomized clinical trial in patients with acquired brain injury

    OpenAIRE

    Gil-Gómez, José-Antonio; Lloréns, Roberto; Alcañiz, Mariano; Colomer, Carolina

    2011-01-01

    Background: Acquired brain injury (ABI) is the main cause of death and disability among young adults. In most cases, survivors can experience balance instability, resulting in functional impairments that are associated with diminished health-related quality of life. Traditional rehabilitation therapy may be tedious. This can reduce motivation and adherence to the treatment and thus provide a limited benefit to patients with balance disorders. We present eBaViR (easy Balance Virtual Rehabilita...

  11. 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) (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) (removal of Cr(III) complexes from contaminated waters. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Sistemas de classificações geotécnicas de solos: estudo de caso aplicado à rodovia não pavimentada vcs 346, Viçosa, MG Geotechnical soil classification systems: case study applied to the vcs 346 unpaved road, Viçosa, MG

    Directory of Open Access Journals (Sweden)

    Taciano Oliveira da Silva

    2010-04-01

    Full Text Available Este artigo aborda uma contribuição às classificações geotécnicas tradicionais de solos Unified Soil Classification System (USC, Transportation Research Board System (TRB e a Metodologia Miniatura, Compactado, Tropical (MCT para um caso aplicado à rodovia municipal não pavimentada VCS 346, no Município de Viçosa, MG, considerando-se várias amostras deformadas de solos coletadas no subleito da referida via. Os principais objetivos deste estudo residem na contribuição de um banco de dados geotécnicos sobre classificações de solos tropicais, bem como na verificação de possíveis agrupamentos entre os sistemas geotécnicos tradicionais de classificação e a metodologia MCT. O programa de laboratório envolveu a realização dos seguintes ensaios: (i granulometria conjunta; (ii limites de Atterberg (LL e LP; (iii massa específica dos grãos do solo; (iv compactação Mini-MCV; e (v perda de massa do corpo-de-prova por imersão em água. Os resultados possibilitaram verificar que, após a classificação das amostras, vários agrupamentos entre os sistemas de classificações geotécnicas tradicionais coincidiram com aqueles já apresentados na metodologia MCT e, considerando a pedogênese da região de Viçosa, MG, para o grupo NG', houve a contribuição dos grupos SC, SM e CL do Sistema USC e do grupo A-4 do Sistema TRB.This paper addresses a contribution to the traditional geotechnical soil classifications systems USC (Unified Soil Classification and TRB (Transportation Research Board, and the MCT methodology (Miniature, Compacted, Tropical applied to a case study involving the laboratory geotechnical characterization of disturbed samples from the subgrade of the VCS 346 municipal unpaved road, located in Viçosa - MG. The main goals of this study are to contribute to the formation of a database directed to the geotechnical classification of tropical soils as well as to verify possible groupings among the traditional

  13. 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...

  14. 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...

  15. Coupling population dynamics with earth system models: the POPEM model.

    Science.gov (United States)

    Navarro, Andrés; Moreno, Raúl; Jiménez-Alcázar, Alfonso; Tapiador, Francisco J

    2017-09-16

    Precise modeling of CO 2 emissions is important for environmental research. This paper presents a new model of human population dynamics that can be embedded into ESMs (Earth System Models) to improve climate modeling. Through a system dynamics approach, we develop a cohort-component model that successfully simulates historical population dynamics with fine spatial resolution (about 1°×1°). The population projections are used to improve the estimates of CO 2 emissions, thus transcending the bulk approach of existing models and allowing more realistic non-linear effects to feature in the simulations. The module, dubbed POPEM (from Population Parameterization for Earth Models), is compared with current emission inventories and validated against UN aggregated data. Finally, it is shown that the module can be used to advance toward fully coupling the social and natural components of the Earth system, an emerging research path for environmental science and pollution research.

  16. Vi-da: vitiligo diagnostic assistance mobile application

    Science.gov (United States)

    Nugraha, G. A.; Nurhudatiana, A.; Bahana, R.

    2018-03-01

    Vitiligo is a skin disorder in which white patches of depigmentation appear on different parts of the body. Usually, patients come to hospitals or clinics to have their vitiligo conditions assessed. This can be very tiring to the patients, as vitiligo treatments usually take a relatively long period of time, which can range from months to years. To address this challenge, we present in this paper a prototype of an Android-based mobile application called Vi-DA, which stands for Vitiligo Diagnostic Assistance. Vi-DA consists of three subsystems, which are user sign-up subsystem, camera and image analysis subsystem, and progress report subsystem. The mobile application was developed in Java programming language and uses MySQL as the database system. Vi-DA adopts a vitiligo segmentation algorithm to segment input image into normal skin area, vitiligo skin area, and non-skin area. Results showed that Vi-DA gave comparable results to the previous system implemented in Matlab. User acceptance testing results also showed that all respondents agreed on the usefulness of the system and agreed to use Vi-DA again in the future. Vi-DA benefits both dermatologists and patients as not only a computer-aided diagnosis (CAD) tool but also as a smart application that can be used for self-assessment at home.

  17. Demarcação de uma grade de trilhas no Centro de Pesquisas da Mata do Paraíso, Viçosa, Minas Gerais Plotting of a trail grid system in the Mata do Paraíso Research Center, Viçosa, State of Minas Gerais

    Directory of Open Access Journals (Sweden)

    Rômulo Ribon

    2005-02-01

    Full Text Available O Centro de Pesquisas da Mata do Paraíso (CPMP é parte integrante do maior fragmento de Floresta Semidecidual Altimontana das imediações do município de Viçosa, sudeste de Minas Gerais. Como centro de pesquisas da Universidade Federal de Viçosa, ele tem servido para a coleta de dados de monografias de graduação, dissertações, teses e pesquisas de professores, principalmente dos Departamentos de Biologia Animal, Biologia Vegetal e Engenharia Florestal. Essas pesquisas têm sido conduzidas em trilhas preexistentes, aleatoriamente distribuídas pela mata, ou em novas trilhas abertas conforme a conveniência dos pesquisadores ou a exigência de suas pesquisas. Essa prática impede ou dificulta o mapeamento adequado de locais de amostragem e os monitoramentos temporal e espacial de comunidades animais e vegetais, bem como a repetibilidade de experimentos. No presente trabalho, descreve-se a implantação de um sistema de trilhas em 40 ha do CPMP, formado por um conjunto de cinco trilhas paralelas de 1.000 m e 11 de 400 m, formando 40 quadrados contíguos de 1 ha. O CPMP passou a ser uma das poucas reservas florestais no país a contar com um sistema ordenado e medido de trilhas, abrindo um novo leque de oportunidades para a realização de pesquisas de importância internacional. Destacam-se a urgência de manutenção das trilhas, a necessidade de seu georreferenciamento e a expansão da grade para 100 ha, a fim de que alcance padrões internacionais entre estações de pesquisa de comunidades florestais na região neotropical.Mata do Paraíso Research Center (CPMP is the core area of the largest Lower Montane Semideciduous Atlantic Forest fragment in Viçosa region, southeastern State of Minas Gerais, Brazil. As a research center belonging to the Universidade Federal de Viçosa (UFV, it has been an important site for the fieldwork of undergraduate monographs, Master and Doctorate Thesis, and research conducted by professors, mostly from

  18. Stellar evolution. VI.

    Science.gov (United States)

    Iben, I., Jr.

    1967-01-01

    Evolution of low mass Population I stars from main sequence to red giant branch in Hertzsprung- Russell diagram, through energy generation phases of p-p chain reactions /dominating over C-N cycle reactions/ and hydrogen burning

  19. Toward a Deterministic Model of Planetary Formation VI: Dynamical Interaction and Coagulation of Multiple Rocky Embryos and Super-Earth Systems around Solar Type Stars

    OpenAIRE

    Ida, S.; Lin, D. N. C.

    2010-01-01

    Radial velocity and transit surveys indicate that solar-type stars bear super-Earths, with mass and period up to ~ 20 M_E and a few months, are more common than those with Jupiter-mass gas giants. In many cases, these super-Earths are members of multiple-planet systems in which their mutual dynamical interaction has influenced their formation and evolution. In this paper, we modify an existing numerical population synthesis scheme to take into account protoplanetary embryos' interaction with ...

  20. Periodic solutions of nonautonomous differential systems modeling obesity population

    International Nuclear Information System (INIS)

    Arenas, Abraham J.; Gonzalez-Parra, Gilberto; Jodar, Lucas

    2009-01-01

    In this paper we study the periodic behaviour of the solutions of a nonautonomous model for obesity population. The mathematical model represented by a nonautonomous system of nonlinear ordinary differential equations is used to model the dynamics of obese populations. Numerical simulations suggest periodic behaviour of subpopulations solutions. Sufficient conditions which guarantee the existence of a periodic positive solution are obtained using a continuation theorem based on coincidence degree theory.

  1. Periodic solutions of nonautonomous differential systems modeling obesity population

    Energy Technology Data Exchange (ETDEWEB)

    Arenas, Abraham J. [Departamento de Matematicas y Estadistica, Universidad de Cordoba Monteria (Colombia)], E-mail: aarenas@sinu.unicordoba.edu.co; Gonzalez-Parra, Gilberto [Departamento de Calculo, Universidad de los Andes, Merida (Venezuela, Bolivarian Republic of)], E-mail: gcarlos@ula.ve; Jodar, Lucas [Instituto de Matematica Multidisciplinar, Universidad Politecnica de Valencia Edificio 8G, 2o, 46022 Valencia (Spain)], E-mail: ljodar@imm.upv.es

    2009-10-30

    In this paper we study the periodic behaviour of the solutions of a nonautonomous model for obesity population. The mathematical model represented by a nonautonomous system of nonlinear ordinary differential equations is used to model the dynamics of obese populations. Numerical simulations suggest periodic behaviour of subpopulations solutions. Sufficient conditions which guarantee the existence of a periodic positive solution are obtained using a continuation theorem based on coincidence degree theory.

  2. 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

  3. 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: ...

  4. Radiosensitivity of Vi bacteriophage 3

    International Nuclear Information System (INIS)

    Zaremba, E.; Kwiatkowski, B.; Ciesielski, B.

    1989-01-01

    The radiosensitivity of Vi bacteriophages 3 under conditions of predominantly indirect radiation effects has been studied. The survival of the phages changed exponentially, with characteristic dose D 0 decreasing, during the first 120 minutes after irradiation due to postirradiation inactivation of the phages. Catalase reduced the toxic features of the irradiated medium. Inactivation of the phages caused by the presence of exogeneous H 2 O 2 in the medium had a similar character to inactivation caused by the medium preirradiated with adequate dose. It is concluded that hydrogen peroxide plays a critical role in postirradiation inactivation of Vi phages 3. 14 refs., 6 figs., 1 tab. (author)

  5. Population and performance analyses of four major populations with Illumina's FGx Forensic Genomics System.

    Science.gov (United States)

    Churchill, Jennifer D; Novroski, Nicole M M; King, Jonathan L; Seah, Lay Hong; Budowle, Bruce

    2017-09-01

    The MiSeq FGx Forensic Genomics System (Illumina) enables amplification and massively parallel sequencing of 59 STRs, 94 identity informative SNPs, 54 ancestry informative SNPs, and 24 phenotypic informative SNPs. Allele frequency and population statistics data were generated for the 172 SNP loci included in this panel on four major population groups (Chinese, African Americans, US Caucasians, and Southwest Hispanics). Single-locus and combined random match probability values were generated for the identity informative SNPs. The average combined STR and identity informative SNP random match probabilities (assuming independence) across all four populations were 1.75E-67 and 2.30E-71 with length-based and sequence-based STR alleles, respectively. Ancestry and phenotype predictions were obtained using the ForenSeq™ Universal Analysis System (UAS; Illumina) based on the ancestry informative and phenotype informative SNP profiles generated for each sample. Additionally, performance metrics, including profile completeness, read depth, relative locus performance, and allele coverage ratios, were evaluated and detailed for the 725 samples included in this study. While some genetic markers included in this panel performed notably better than others, performance across populations was generally consistent. The performance and population data included in this study support that accurate and reliable profiles were generated and provide valuable background information for laboratories considering internal validation studies and implementation. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Connecting micro dynamics and population distributions in system dynamics models.

    Science.gov (United States)

    Fallah-Fini, Saeideh; Rahmandad, Hazhir; Chen, Hsin-Jen; Xue, Hong; Wang, Youfa

    2013-01-01

    Researchers use system dynamics models to capture the mean behavior of groups of indistinguishable population elements (e.g., people) aggregated in stock variables. Yet, many modeling problems require capturing the heterogeneity across elements with respect to some attribute(s) (e.g., body weight). This paper presents a new method to connect the micro-level dynamics associated with elements in a population with the macro-level population distribution along an attribute of interest without the need to explicitly model every element. We apply the proposed method to model the distribution of Body Mass Index and its changes over time in a sample population of American women obtained from the U.S. National Health and Nutrition Examination Survey. Comparing the results with those obtained from an individual-based model that captures the same phenomena shows that our proposed method delivers accurate results with less computation than the individual-based model.

  7. Connecting micro dynamics and population distributions in system dynamics models

    Science.gov (United States)

    Rahmandad, Hazhir; Chen, Hsin-Jen; Xue, Hong; Wang, Youfa

    2014-01-01

    Researchers use system dynamics models to capture the mean behavior of groups of indistinguishable population elements (e.g., people) aggregated in stock variables. Yet, many modeling problems require capturing the heterogeneity across elements with respect to some attribute(s) (e.g., body weight). This paper presents a new method to connect the micro-level dynamics associated with elements in a population with the macro-level population distribution along an attribute of interest without the need to explicitly model every element. We apply the proposed method to model the distribution of Body Mass Index and its changes over time in a sample population of American women obtained from the U.S. National Health and Nutrition Examination Survey. Comparing the results with those obtained from an individual-based model that captures the same phenomena shows that our proposed method delivers accurate results with less computation than the individual-based model. PMID:25620842

  8. The population dynamics of bacteria, phage and RM Systems

    Science.gov (United States)

    Guet, Calin; Levin, Bruce; Pleska, Maros

    Viruses drive and mediate bacterial evolution as parasites and vectors of horizontal gene transfer, respectively. Temperate bacteriophages, defined by the ability to lysogenize a fraction of hosts and to transmit horizontally as well as vertically in the form of prophages, frequently carry genes that increase fitness or contribute to bacterial pathogenicity. Restriction-modification (RM) systems, which are widely diverse and ubiquitous among bacteria, can prevent infections leading to lysis, but their effect on lysogeny is not clear. We show that RM systems prevent lytic and lysogenic infections to the same extent and therefore represent a molecular barrier to prophage acquisition. Surprisingly, we find that this negative effect can be overcome and even reversed at the population level, as a consequence of dynamic interactions between viruses, hosts and RM systems. Thus the population dynamics of bacteria carrying RM systems impacts bacterial genome-wide evolution. .

  9. Raman spectral titration method: an informative technique for studying the complexation of uranyl with uranyl(vi)-DPA/oxalate systems as examples.

    Science.gov (United States)

    Liu, Qian; Zhang, Qianci; Yang, Suliang; Zhu, Haiqiao; Liu, Quanwei; Tian, Guoxin

    2017-10-10

    The Raman band at about 870 cm -1 originating from the symmetric stretch vibration (ν 1 ) of uranyl, UO 2 2+ , has proven to be very informative for investigating the complexation of uranyl using perchlorate or nitrate of known concentration as internal standards. The concentration of uranyl can be conveniently calculated by using the ratio of the directly read band intensities of uranyl and the added reference, ClO 4 - , with a factor of 1.72. While with NO 3 - of concentration lower than 1.8 M as the reference, a factor of 0.85 should be used. Furthermore, with added internal standards, the linear relationship between the Raman intensity and the concentration of the corresponding species is illustrated by the spectral titration of U(vi) with a very strong ligand, dipicolinic acid (DPA); and the application of a spectral titration method with Raman spectroscopy in studying the complexation of uranyl is demonstrated by the titration of U(vi) with oxalate. The stepwise changes in the Raman shift of 18, 17, and 6 cm -1 , corresponding to the three oxalate anions successively bonding to UO 2 2+ , imply that the coordination modes are different. In the 1 : 1 and 1 : 2 ratios of metal to ligand complexes, the oxalate anions bond to the uranyl ion in side-on bidentate mode, but in the 1 : 3 complex the third oxalate bonds in head-on mode, which is much weaker than the first two.

  10. Population Balance Modeling of Aggregation and Coalescence in Colloidal Systems

    NARCIS (Netherlands)

    Kryven, I.; Lazzari, S.; Storti, G.

    2014-01-01

    A complex interplay between aggregation and coalescence occurs in many colloidal polymeric systems and determines the morphology of the final clusters of primary particles. To describe this process, a 2D population balance equation (PBE) based on cluster mass and fractal dimension is solved,

  11. 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

  12. Vi har brug for skammere

    DEFF Research Database (Denmark)

    Holm, Claus

    2007-01-01

    Skammen er en væsentlig ingrediens i opdragelsen af børn, men det overser vi, for skam er et fyord i den pædagogiske verden. Interview med børnebogsforfatteren Lene Kaaberbøl om, hvorfor skam gør os menneskelige....

  13. (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, ...

  14. Microbial populations causing off-flavour in recirculated aquaculture systems

    DEFF Research Database (Denmark)

    Lukassen, Mie Bech; Schramm, Edward; Nielsen, Jeppe Lund

    the distribution of geoA in more than 50 European and Brazilian aquaculture systems has allowed us to identify the diversity among geosmin-producing bacteria. The different populations of geosmin-producers were evaluated relative to plant design, environmental and operational parameters in full-scale aquaculture...... systems using multivariate statistics. The influencing parameters identified were subsequently validated by testing their gene expressions in well-controlled pilot scale aquaculture systems. The results show that the geoA gene is a relative well-conserved gene with limited horizontal gene transfer events...... phase. Furthermore, the gene expressions of the individual groups show positive correlations to the organic loading and presence of oxygen. The current study reveals the presence of important populations involved in geosmin production and which parameters are of importance for their presence...

  15. 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...

  16. 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...

  17. 29 CFR 1910.1026 - Chromium (VI).

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 6 2010-07-01 2010-07-01 false Chromium (VI). 1910.1026 Section 1910.1026 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...

  18. The Duffy blood group system in the Tunisian population.

    Science.gov (United States)

    Ouchari, M; Romdhane, H; Chakroun, T; Abdelkefi, S; Jarrey, I; Houissa, B; Jemni Yacoub, S

    2015-06-01

    Tunisia was described to as genetically heterogenous. Besides the 1% native Berber, the genetically influence of the Europeans seems much larger than that of sub-Saharan populations. Due to their ethnic variability, blood group variants have the potential to support population analyses. The aim of this study was to estimate the Duffy blood group system in this mixed population with enhanced characterization of samples with aberrant expression. Standard serological testing for the Duffy antigen was done for 105 Tunisian blood donors. Samples with altered Fy expression underwent DNA sequencing of the DARC, RHD and RHCE genes. The Fy(a-b+) was the most common phenotype identified in the Tunisian population (38.1%). Five samples with Fy(a-b-) phenotype were determined as FY*02N.01/FY*02N.01 by a homozygous occurrence of the FY*B-67C>T alteration. Another three individuals exhibited a Fy(b+(w))Fy(x) expression, confirmed by a FY*A/FY*02M.01 (n = 1) and a FY*02M.01/FY*02M.01 (n = 2) genotype. RHD and RHCE sequencing (n= 8) revealed altered alleles observed in black populations in 5 samples. One individual with FY*02M.01/FY*02M.01 have the silent 165C>T nucleotide substitution each in the RHD and RHCE gene. The composition of blood group variants determined in this study confirms the genetically proximity of Tunisia to Europe. The small sub-Saharan genetic influence was approved by a limited number of variant samples associated with the black population. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  19. Vi mangler endnu et panel

    DEFF Research Database (Denmark)

    Ritter, Thomas

    2016-01-01

    Vi mangler højtuddannede værdiskabere, som transformerer gode idéer og teknologier til indtjening og velstand. Først i mødet med markedet afgøres fremtiden. Troels Lund Poulsen bør nedsætte et kommercialiseringspanel, der byder ind med løsninger, hvordan Danmark bliver et land ikke kun med gode i...

  20. 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.

  1. Development of regional wheat VI-LAI models using Resourcesat-1 ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 120; Issue 6. Development of regional wheat VI-LAI models using Resourcesat-1 AWiFS data ... The present study aimed at developing empirical vegetation index VI-LAI models for wheat using AWiFS optical data in four bands and in-situ measurements sampled ...

  2. Retention of U(VI) onto silica in presence of model organic molecules

    Energy Technology Data Exchange (ETDEWEB)

    Pham, T.T.H.; Mercier-Bion, F.; Drot, R.; Lagarde, G.; Simoni, E. [Groupe de Radiochimie, IPNO, Universite Paris 11, Orsay, 91406 (France); Lambert, J. [LCPME, 405 rue de Vandoeuvre, Villers-les-Nancy, 54600 (France)

    2008-07-01

    It is well-known that the organic matter influences the retention of ions onto mineral surfaces. However, the major part of concerned studies implies humic substances and complex solids. Another approach for identifying the sorption mechanisms is possible by studying simpler solids than those present in natural medium. So, silica is chosen as mineral surface because of its abundance in soils and of the presence of Si-O groups in clayey minerals. Uranium (VI) is selected as cation. Simple organic molecules like acetic (one carboxylic group) and oxalic (two carboxylic functions) acids are considered as models of the natural organic matter for understanding their role in the retention of U(VI) onto powders and slides of silica. Binary (organics/silica, U(VI)/silica) and ternary systems (organics/silica/U(VI)) are studied by complementary approaches. Sorption edges as function of pH are obtained by liquid scintillation methods and capillary electrophoresis. Different spectroscopic techniques are used to deduce the interactions between the organic matter and U(VI) sorbed onto the silica whose: Time-Resolved Laser induced Fluorescence Spectroscopy (TRLFS), X-ray Photoelectron Spectroscopy (XPS), Nuclear Microprobe Analysis (NMA). The results of the effect of these model organic molecules onto the U(VI) retention showed a good agreement between the different techniques. Concerning the acetic acid, there are not differences in the sorption percentages of uranyl (see the figure). All these results indicate that the uranyl-acetate complexes stay in the aqueous solution rather than sorbing onto the silica. On the contrary, oxalic acid influences the sorption of U(VI) onto the silica surface. The sorption percentage of U(VI) in the ternary system (oxalic acid/silica/U(VI)) is lower than the binary system (U(VI)/silica) (see the figure). So, the presence of oxalic acid decreases the sorption of U(VI) onto the silica surface. (authors)

  3. Effect of flavin compounds on uranium(VI) reduction- kinetic study using electrochemical methods with UV-vis spectroscopy

    International Nuclear Information System (INIS)

    Yamasaki, Shinya; Tanaka, Kazuya; Kozai, Naofumi; Ohnuki, Toshihiko

    2017-01-01

    The reduction of uranium hexavalent (U(VI)) to tetravalent (U(IV)) is an important reaction because of the change in its mobility in the natural environment. Although the flavin mononucleotide (FMN) has acted as an electron shuttle for the U(VI) reduction in vivo system, which is called an electron mediator, only the rate constant for the electron transfer from FMN to U(VI) has been determined. This study examined the rate constant for the U(VI) reduction process by three flavin analogues (riboflavin, flavin mononucleotide, flavin adenine dinucleotide) to elucidate their substituent group effect on the U(VI) reduction rate by electrochemical methods. The formation of the U(IV) was monitored by UV-vis spectrometry at 660 nm during the constant potential electrolysis of the U(VI) solution in the presence of the mediator. The cyclic voltammograms indicated that the three flavin analogues behaved as electron mediator to reduce U(VI). The logarithmic rate constant for the U(VI) reduction was related to the standard redox potential of the mediators. This linear relationship indicated that the redox-active group of the mediator and the substituent group of the mediator dominate capability of the U(VI) reduction and its rate, respectively. The apparent reduction potential of U(VI) increased about 0.2 V in the presence of the mediators, which strongly suggests that the biological electron mediator makes the U(VI) reduction possible even under more oxidative conditions. - Highlights: • The rate constant for the U(VI) reduction by flavin analogues was determined. • The flavins showed a mediator effect on the U(VI) reduction. • The logarithmic rate constants for the U(VI) reduction was proportional to redox potential of the mediator. • The presence of the mediator increased about 0.2 V apparent redox potential of U(VI) to U(IV).

  4. Stochastic population dynamics in spatially extended predator-prey systems

    Science.gov (United States)

    Dobramysl, Ulrich; Mobilia, Mauro; Pleimling, Michel; Täuber, Uwe C.

    2018-02-01

    Spatially extended population dynamics models that incorporate demographic noise serve as case studies for the crucial role of fluctuations and correlations in biological systems. Numerical and analytic tools from non-equilibrium statistical physics capture the stochastic kinetics of these complex interacting many-particle systems beyond rate equation approximations. Including spatial structure and stochastic noise in models for predator-prey competition invalidates the neutral Lotka-Volterra population cycles. Stochastic models yield long-lived erratic oscillations stemming from a resonant amplification mechanism. Spatially extended predator-prey systems display noise-stabilized activity fronts that generate persistent correlations. Fluctuation-induced renormalizations of the oscillation parameters can be analyzed perturbatively via a Doi-Peliti field theory mapping of the master equation; related tools allow detailed characterization of extinction pathways. The critical steady-state and non-equilibrium relaxation dynamics at the predator extinction threshold are governed by the directed percolation universality class. Spatial predation rate variability results in more localized clusters, enhancing both competing species’ population densities. Affixing variable interaction rates to individual particles and allowing for trait inheritance subject to mutations induces fast evolutionary dynamics for the rate distributions. Stochastic spatial variants of three-species competition with ‘rock-paper-scissors’ interactions metaphorically describe cyclic dominance. These models illustrate intimate connections between population dynamics and evolutionary game theory, underscore the role of fluctuations to drive populations toward extinction, and demonstrate how space can support species diversity. Two-dimensional cyclic three-species May-Leonard models are characterized by the emergence of spiraling patterns whose properties are elucidated by a mapping onto a complex

  5. Systematic evaluation program review of NRC Safety Topic VI-10.A associated with the electrical, instrumentation and control portions of the testing of reactor trip system and engineered safety features, including response time for the Dresden station, Unit II nuclear power plant

    International Nuclear Information System (INIS)

    St Leger-Barter, G.

    1980-11-01

    This report documents the technical evaluation and review of NRC Safety Topic VI-10.A, associated with the electrical, instrumentation, and control portions of the testing of reactor trip systems and engineered safety features including response time for the Dresden II nuclear power plant, using current licensing criteria

  6. Mutations in ARSB in MPS VI patients in India

    Directory of Open Access Journals (Sweden)

    Juby Mathew

    2015-09-01

    Full Text Available Mucopolysaccharidosis VI (MPS VI is an autosomal recessive inborn error of metabolism caused by mutations in the arylsulfatase B gene (ARSB and consequent deficient activity of ARSB, a lysosomal enzyme. We present here the results of a study undertaken to identify the mutations in ARSB in MPS VI patients in India. Around 160 ARSB mutations, of which just 4 are from India, have been reported in the literature. Our study covered nine MPS VI patients from eight families. Both familial mutations were found in seven families, and only one mutation was found in one family. Seven mutations were found — four novel (p.G38_G40del3, p.C91R, p.L98R and p.R315P, two previously reported from India (p.D53N and p.W450C, and one reported from outside India (p.R160Q. One mutation, p.W450C, was present in two families, and the other six mutations were present in one family each. Analysis of the molecular structure of the enzyme revealed that most of these mutations either cause loss of an active site residue or destabilize the structure of the enzyme. The only previous study on mutations in ARSB in Indian MPS VI patients, by Kantaputra et al. 2014 [1], reported four novel mutations of which two (p.D53N and p.W450C were found in our study as well. Till date, nine mutations have been reported from India, through our study and the Kantaputra study. Eight out of these nine mutations have been found only in India. This suggests that the population studied by us might have its own typical set of mutations, with other populations equally likely to have their own set of mutations.

  7. Influence of magnetic field on Cr(VI) adsorption capability of given anaerobic sludge.

    Science.gov (United States)

    Xu, Y B; Duan, X J; Yan, J N; Sun, S Y

    2010-02-01

    To provide beneficial guide for the application of the magnetic field in the bio-treatment of the Cr(VI)-contained wastewater, sludge samples from the control bio-system A (absent of magnetic field) and the contrast bio-system B (present of magnetic field) were used to adsorb the synthetic wastewater with 100 mg l(-1) Cr(VI). Influences of two adsorption modes, single adsorption and once continuous adsorption, on the Cr(VI) adsorption capacities of both sludge samples were compared. And the influence of regeneration on the Cr(VI) adsorption capacities were also studied. The results of adsorption experiments showed that the Cr(VI) adsorption capacities of the first single adsorption for sludge sample A and B were pretty nearly, which were 9.79 and 9.93 mg, respectively. And after 5 single adsorption periods, the total Cr(VI) adsorption capacity and efficiency of the sample B were 25.88 and 55.66 mg Cr(VI) g(-1)VSS, while those of the control were 14.95 and 33.98 mg Cr(VI) g(-1)VSS, respectively. For the sludge sample A and B after a single adsorption, both functions of regeneration were remarkable. But after 13 cycles of the single adsorption-regeneration, the Cr(VI) adsorption capacity and efficiency of the sample B were 110.15 and 189.91 mg Cr(VI) g(-1)VSS, while those of the control were 70.89 and 140.38 mg Cr(VI) g(-1)VSS, respectively. Though the Cr(VI) adsorption capacity of a once continuous adsorption period was more than that of a single adsorption period obviously, the Cr(VI) removal rates of the sludge sample A and B in the third period of once continuous adsorption-regeneration were only 8.12 and 33.51%, respectively. It was concluded that the weak magnetic field did improve the Cr(VI) bio-removal efficiency and the sludge stability, the batch treatment was an ideal operation mode for the bio-treatment of the Cr(VI)-contained wastewater, as compared with the continuous operation mode, but regeneration and enough sludge content were two necessary

  8. Interdisciplinarity and Systems Science to Improve Population Health

    Science.gov (United States)

    Mabry, Patricia L.; Olster, Deborah H.; Morgan, Glen D.; Abrams, David B.

    2008-01-01

    Fueled by the rapid pace of discovery, humankind's ability to understand the ultimate causes of preventable common disease burdens and to identify solutions is now reaching a revolutionary tipping point. Achieving optimal health and well-being for all members of society lies as much in the understanding of the factors identified by the behavioral, social, and public health sciences as by the biological ones. Accumulating advances in mathematical modeling, informatics, imaging, sensor technology, and communication tools have stimulated several converging trends in science: an emerging understanding of epigenomic regulation; dramatic successes in achieving population health-behavior changes; and improved scientific rigor in behavioral, social, and economic sciences. Fostering stronger interdisciplinary partnerships to bring together the behavioral–social–ecologic models of multilevel “causes of the causes” and the molecular, cellular, and, ultimately, physiological bases of health and disease will facilitate breakthroughs to improve the public's health. The strategic vision of the Office of Behavioral and Social Sciences Research (OBSSR) at the National Institutes of Health (NIH) is rooted in a collaborative approach to addressing the complex and multidimensional issues that challenge the public's health. This paper describes OBSSR's four key programmatic directions (next-generation basic science, interdisciplinary research, systems science, and a problem-based focus for population impact) to illustrate how interdisciplinary and transdisciplinary perspectives can foster the vertical integration of research among biological, behavioral, social, and population levels of analysis over the lifespan and across generations. Interdisciplinary and multilevel approaches are critical both to the OBSSR's mission of integrating behavioral and social sciences more fully into the NIH scientific enterprise and to the overall NIH mission of utilizing science in the pursuit

  9. Elderly population in the prison system: a look behind bars

    Directory of Open Access Journals (Sweden)

    Hércules de Oliveira Carmo

    2012-09-01

    Full Text Available This work is a present reality in this century, and that is demanding attention, especially in the context of public health and human rights - the elderly-con. A complex problem that arose for our consideration is that the person who, besides being old, and the inmate is most often in pain, due to a pathological condition related to organic factors, mental or subjective, in old age, worsens. Without being accompanied by public policies, these realities are not provided before, we now gain a greater complexity in the prison context, reveal an increase of HIV / AIDS, the presence of sexually transmitted disease, increased depression and neuropsychiatric diseases. The questions posed in this research, which attempted to answer here may well be subsumed: - How to think the nursing practices before the issue of the growing aging population with its pathologies further complexizadas in prison? The objective, therefore, this study: (i to investigate the growing presence of the elderly Brazilian penitentiary system, based on existing literature, (ii verify the potential risk factors on the health of the elderly population in the Brazilian prison system, and the weight the presence of a nursing team in this context. Urgent attention, therefore, it is required of health professionals, authorities and civil society to the complexity of aging silenced behind bars.

  10. Investigations of HRC®-Stimulated Bioreduction of Cr(VI) at Hanford 100H

    Energy Technology Data Exchange (ETDEWEB)

    Hazen, T.C.; Faybishenko, B.; Joyner, D.; Borglin, S.; Brodie, E.; Hubbard, S.; Williams, K.; Peterson, J.; Wan, J.; Tokunaga, T.; Firestone, M.; Long, P.E.; Resch, C.T.; Cantrell, K.; Newcomer, D.; Koenigsberg, S.; Willet, A.

    2006-04-05

    Hypothesis: Lactate (Hydrogen Release Compound-HRC{trademark}) injection into chromium contaminated groundwater through an injection well will cause indirect or direct bioreduction of chromate [Cr(VI)] and precipitation of insoluble species of [Cr(III)] on soil particles, probably catalyzed at oxide surfaces, at the field scale. Objective: Assess the potential for immobilizing and detoxifying chromium-contaminated groundwater using lactate-stimulated bioreduction of Cr(VI) to Cr(III) at the Hanford Site's 100-H Area field site. Types of Research: A three-well system (injection well and upgradient and downgradient monitoring wells) was used for conducting the in situ biostimulation and monitoring. To assess the pre- and post-injection test groundwater conditions, we used an integrated monitoring approach, involving hydraulic, geochemical, microbial, and geophysical techniques and analytical methods, as well as conducted five Br-tracer injection tests and four pumping tests (concurrently with the Br-tracer tests). Groundwater biostimulation was conducted by injection of 40 lbs of {sup 13}C-labeled HRC into the injection well (over the depth interval from 44-50 ft) on 8/3/2004, followed by low-flow pumping (1.2 to 2.5 l/min) through the downgradient well (to ensure capture of groundwater flow lines passing through the injection well) for 27 days. Main Results: Although the total microbial population in sediments is relatively low (<10{sup 5} cells g{sup -1}) under background conditions, which is likely insufficient for direct enzymatic Cr(VI) reduction, several types of bacteria, e.g., Bacillus/Arthrobacter and Geobacter, are present in the Hanford sediments, which are known to reduce or sorb hexavalent chromium. The HRC injection stimulated microbial cell counts to reach the maximum of 2 x 10{sup 7} cells g{sup -1} 13-17 days after the injection, and generated highly reducing conditions. Geochemical and isotopic observations confirmed microbial metabolism of HRC

  11. Investigations of HRC®-Stimulated Bioreduction of Cr(VI) at Hanford 100H

    Energy Technology Data Exchange (ETDEWEB)

    T.C. Hazen; B. Faybishenko; D. Joyner; S. Borglin; E.Brodie; S. Hubbard; K. Williams; J. Peterson; J. Wan; T. Tokunaga; Long, P.E.; Newcomer, D.; Koenigsberg, S.; Willet, A.

    2005-04-18

    Hypothesis: Lactate (Hydrogen Release Compound-HRC{trademark}) injection into chromium contaminated groundwater through an injection well will cause indirect or direct bioreduction of chromate [Cr(VI)] and precipitation of insoluble species of [Cr(III)] on soil particles, probably catalyzed at oxide surfaces, at the field scale. Objective: Assess the potential for immobilizing and detoxifying chromium-contaminated groundwater using lactate-stimulated bioreduction of Cr(VI) to Cr(III) at the Hanford Site's 100-H Area field site. Types of Research: A three-well system (injection well and upgradient and downgradient monitoring wells) was used for conducting the in situ biostimulation and monitoring. To assess the pre- and post-injection test groundwater conditions, we used an integrated monitoring approach, involving hydraulic, geochemical, microbial, and geophysical techniques and analytical methods, as well as conducted five Br-tracer injection tests and four pumping tests (concurrently with the Br-tracer tests). Groundwater biostimulation was conducted by injection of 40 lbs of {sup 13}C-labeled HRC into the injection well (over the depth interval from 44-50 ft) on 8/3/2004, followed by low-flow pumping (1.2 to 2.5 l/min) through the downgradient well (to ensure capture of groundwater flow lines passing through the injection well) for 27 days. Main Results: Although the total microbial population in sediments is relatively low (<10{sup 5} cells g-1) under background conditions, which is likely insufficient for direct enzymatic Cr(VI) reduction, several types of bacteria, e.g., Bacillus/Arthrobacter and Geobacter, are present in the Hanford sediments, which are known to reduce or sorb hexavalent chromium. The HRC injection stimulated microbial cell counts to reach the maximum of 2 x 10{sup 7} cells g{sup -1} 13-17 days after the injection, and generated highly reducing conditions. Geochemical and isotopic observations confirmed microbial metabolism of HRC. The

  12. Study of new U(VI) and Pu(VI) coprecipitation methods for the preparation of (U,Pu)O2

    International Nuclear Information System (INIS)

    Sanoit, J. de.

    1990-01-01

    Two U(VI) and Pu(VI) coprecipitation methods have been studied, for the definition of new processes to prepare (U,Pu)O 2 mixed oxides suitable for making MoX fuels or fast breeder reactor fuels. The first system is based on the coprecipitation of a new U(VI), Pu(VI) compound; ammonium uranoplutonate, where as a second system is related to the precipitation of uranyl plutonyl monocarbonate. Experimental conditions to optimize the precipitation and the filtration steps of these two systems have been determined. After calcination under reducing conditions, the mixed oxides obtained are characterized according to different techniques: granulometry, thermogravimetry, solubility in boiling HNO 3 solutions. The properties of such oxides are excellent. The possible processes for preparing (U, Pu)O 2 using these new routes are compared with those actually exploited [fr

  13. Probing uranyl(VI) speciation in the presence of amidoxime ligands using electrospray ionization mass spectrometry.

    Science.gov (United States)

    Mustapha, Adetayo M; Pasilis, Sofie P

    2013-10-15

    Extraction processes using poly(acrylamidoxime) resins are being developed to extract uranium from seawater. The main complexing agents in these resins are thought to be 2,6-dihydroxyiminopiperidine (DHIP) and N(1),N(5)-dihydroxypentanediimidamide (DHPD), which form strong complexes with uranyl(VI) at the pH of seawater. It is important to understand uranyl(VI) speciation in the presence of these and similar amidoxime ligands to understand factors affecting uranyl(VI) adsorption to the poly(acrylamidoxime) resins. Experiments were carried out in positive ion mode on a quadrupole ion trap mass spectrometer equipped with an electrospray ionization source. The ligands investigated were DHIP, DHPD, and N(1),N(2)-dihydroxyethanediimidamide (DHED). DHED and DHPD differ only in the number of carbons separating the oxime groups. The effects on the mass spectra of changes in uranyl(VI):ligand ratio, pH, and ligand type were examined. DHIP binds uranyl(VI) more effectively than DHPD or DHED in the pH range investigated, forming ions derived from solution-phase species with uranyl(VI):DHIP stoichiometries of 1:1, 1:2, and 2:3. The 2:3 uranyl(VI):DHIP complex appears to be a previously undescribed solution species. Ions related to uranyl(VI):DHPD complexes were detected in very low abundance. DHED is a more effective complexing agent for uranyl(VI) than DHPD, forming ions having uranyl(VI):DHED stoichiometries of 1:1, 1:2, 1:3, and 2:3. This study presents a first look at the solution chemistry of uranyl(VI)-amidoxime complexes using electrospray ionization mass spectrometry. The appearance of previously undescribed solution species suggests that the uranyl-amidoxime system is a rich and relatively complex one, requiring a more in-depth investigation. Copyright © 2013 John Wiley & Sons, Ltd.

  14. Uranium(VI) sorption on iron oxides in Hanford Site sediment: Application of a surface complexation model

    International Nuclear Information System (INIS)

    Um, Wooyong; Serne, R. Jeffrey; Brown, Christopher F.; Rod, Kenton A.

    2008-01-01

    Sorption of U(VI) on Hanford fine sand (HFS) with varying Fe-oxide (especially ferrihydrite) contents showed that U(VI) sorption increased with the incremental addition of synthetic ferrihydrite into HFS, consistent with ferrihydrite being one of the most reactive U(VI) sorbents present in natural sediments. Surface complexation model (SCM) calculations for U(VI) sorption, using only U(VI) surface-reaction constants obtained from U(VI) sorption data on freshly synthesized ferrihydrite at different pHs, were similar to the measured U(VI) sorption results on pure synthetic ferrihydrite and on HFS with high contents of ferrihydrite (5 wt%) added. However, the SCM prediction using only U(VI) sorption reactions and constants for synthetic ferrihydrite overestimated U(VI) sorption on the natural HFS or HFS with addition of low amounts of added ferrihydrite (1 wt% added). Over-predicted U(VI) sorption was attributed to reduced reactivity of natural ferrihydrite present in Hanford Site sediments, compared to freshly prepared synthetic ferrihydrite. Even though the SCM general composite (GC) approach is considered to be a semi-quantitative estimation technique for contaminant sorption, which requires systematic experimental data on the sorbent-sorbate system being studied to obtain credible SCM parameters, the general composite SCM model was still found to be a useful technique for describing U(VI) sorption on natural sediments. Based on U(VI) batch sorption results, two simple U(VI) monodentate surface species, SO U O 2 HCO 3 and SO U O 2 OH on ferrihydrite and phyllosillicate in HFS, respectively, can be successfully used to describe U(VI) sorption onto Hanford Site sediment contacting varying geochemical solutions

  15. 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.

  16. Spectrum and energy levels of Y VI

    International Nuclear Information System (INIS)

    Persson, W.; Reader, J.

    1986-01-01

    The spectrum of the five-times-ionized yttrium atom (Y VI), excited in a sliding-spark discharge, was studied in the 160--2500 A-circle range. About 900 Y VI lines were classified as transitions between 101 odd and 69 even energy levels.The energy-level system established includes almost all levels of the 4s 2 4p 4 , 4s4p 5 , 4s 2 4p 3 4d, 5d, 5s, 6s, and 5p configurations and a number of levels of the 7s, 4f, and 4s4p 4 4d configurations. The observed level system has been theoretically interpreted by means of Hartree--Fock calculations and least-squares parametric fits. Strong configuration mixings are found between the 4s4p 5 and 4s 2 4p 3 4d configurations, between the 4s 2 4p 3 5p and 4s4p 4 4d configurations, and between the 4s 2 4p 3 4f and 4s4p 4 4d configurations. From the optimized energy-level values, a system of Ritz-type wavelength standards with accuracies varying from 0.0003 to 0.003 A-circle in the range 179--500 A-circle has been determined. The ionization energy as determined from 4s 2 4p 3 ns levels (n = 5-7) is 737 110 +- 200 cm/sup -1/ (91.390 +- 0.025 eV)

  17. Reduction of trace quantities of chromium(VI by strong acids

    Directory of Open Access Journals (Sweden)

    Pezzin Sérgio H

    2004-01-01

    Full Text Available The chemical behavior of Cr(VI at low concentrations (10-4 to 10-7 mol L-1 in several strong acids was studied using high specific activity 51Cr(VI as a tracer. The speciation of the products from these systems was carried out by ion exchange chromatography with stepwise elution. The results show that trace quantities of Cr(VI, monitored by means of radiochromium (51Cr, are reduced in the presence of mineral acids such as perchloric, hydrochloric, hydrofluoric, sulfuric, nitric and trifluoromethanesulfonic acids, even in the absence of conventional reducing agents, producing different measureable Cr(III species, depending on the acid anion. Detailed studies of the reduction of low concentrations of Cr(VI with nitric acid have shown that the relative rate of reduction increases as the concentration of the acid increases or as the concentration of the Cr(VI decreases.

  18. Oxidation of Sulfonamides in Aqueous Solution by UV-TiO2-Fe(VI

    Directory of Open Access Journals (Sweden)

    Yan Ma

    2015-01-01

    Full Text Available The photocatalytic degradation of sulfonamides in aqueous TiO2 suspension under UV irradiation has been investigated using potassium ferrate as electron acceptors. The results showed that the stability of Fe(VI is dependent on pH significantly, and the stability reduces obviously in the presence of UV-TiO2. The experiments indicated that Fe(VI could effectively scavenge the conduction band electrons from the surface of TiO2. The photocatalytic oxidation of sulfonamides with Fe(VI was found to be much faster than that without Fe(VI. The SD, SM, and SMX concentration was greatly reduced by 89.2%, 83.4%, and 82.0%, respectively, after 10 min with UV-TiO2-Fe(VI, comparing to 65.2%, 66.0%, and 71.9%, respectively, with Fe(VI only in the dark and 71.3%, 72.7%, and 76.0%, respectively, with UV-TiO2. The pH value of solution significantly influenced the sulfonamides degradation in UV-TiO2-Fe(VI system. The degradation amount of sulfonamides after 10 min was a maximum at pH 7. The intermediate products of sulfonamides oxidation by UV-TiO2-Fe(VI were analysed by LC-HESI-MS-MS and the results suggested that a majority of sulfonamides turned into large-molecule products without complete mineralization.

  19. Type VI Secretion Effectors: Methodologies and Biology

    Directory of Open Access Journals (Sweden)

    Yun-Wei Lien

    2017-06-01

    Full Text Available The type VI secretion system (T6SS is a nanomachine deployed by many Gram-negative bacteria as a weapon against eukaryotic hosts or prokaryotic competitors. It assembles into a bacteriophage tail-like structure that can transport effector proteins into the environment or target cells for competitive survival or pathogenesis. T6SS effectors have been identified by a variety of approaches, including knowledge/hypothesis-dependent and discovery-driven approaches. Here, we review and discuss the methods that have been used to identify T6SS effectors and the biological and biochemical functions of known effectors. On the basis of the nature and transport mechanisms of T6SS effectors, we further propose potential strategies that may be applicable to identify new T6SS effectors.

  20. 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...

  1. Influence of Calcite and Dissolved Calcium on Uranium(VI) Sorption to a Hanford Subsurface Sediment

    International Nuclear Information System (INIS)

    Dong, Wenming; Ball, William P.; Liu, Chongxuan; Wang, Zheming; Stone, Alan T.; Bai, Jing; Zachara, John M.

    2005-01-01

    The influence of calcite and dissolved calcium on U(VI) adsorption was investigated using a calcite-containing sandy silt/clay sediment from the U. S. Department of Energy Hanford site. U(VI) adsorption to sediment, treated sediment, and sediment size fractions was studied in solutions that both had and had not been preequilibrated with calcite, at initial [U(VI)] ) 10-7-10-5 mol/L and final pH ) 6.0- 10.0. Kinetic and reversibility studies (pH 8.4) showed rapid sorption (30 min), with reasonable reversibility in the 3-day reaction time. Sorption from solutions equilibrated with calcite showed maximum U(VI) adsorption at pH 8.4 (0.1. In contrast, calcium-free systems showed the greatest adsorption at pH 6.0-7.2. At pH > 8.4, U(VI) adsorption was identical from calcium-free and calcium-containing solutions. For calcite-presaturated systems, both speciation calculations and laser-induced fluorescence spectroscopic analyses indicated that aqueous U(VI) was increasingly dominated by Ca2UO2(CO3)3 0(aq) at pH<8.4 and that formation of Ca2UO2(CO3)3 0(aq) is what suppresses U(VI) adsorption. Above pH 8.4, aqueous U(VI) speciation was dominated by UO2(CO3)3 4- in all solutions. Finally, results also showed that U(VI) adsorption was additive in regard to size fraction but not in regard to mineral mass: Carbonate minerals may have blocked U(VI) access to surfaces of higher sorption affinity

  2. Simultaneous determination of chromium(III) and chromium(VI) in aqueous solutions by ion chromatography and chemiluminescence detection

    DEFF Research Database (Denmark)

    Gammelgaard, Bente; Jøns, O; Nielsen, B

    1992-01-01

    A method for the simultaneous determination of chromium(iii) and chromium(vi) in a flow system based on chemiluminescence was developed. A Dionex cation-exchange guard column was used to separate chromium(iii) from chromium(vi), and chromium(vi) was reduced by potassium sulfite, whereupon both...... species were detected by use of the luminol-hydrogen peroxide chemiluminescence system. Linear calibration for both species was established over the concentration range 1-1000 micrograms l-1. The precision at the 20 micrograms l-1 level was 3.5% for chromium(iii) and 3.3% for chromium(vi), respectively...

  3. Integrated powertrain control for optimal CO2-NOx tradeoff in an Euro-VI diesel engine with waste heat recovery system

    NARCIS (Netherlands)

    Willems, F.P.T.; Kupper, F.; Cloudt, R.P.M.

    2012-01-01

    This study presents an integrated energy and emission management strategy which minimizes the operational costs over the study test cycle. This Integrated Powertrain Control (IPC) strategy deals with high system complexity and exploits the synergy between engine-aftertreatment systems by following a

  4. 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...

  5. 76 FR 60593 - Title VI; Proposed Circular

    Science.gov (United States)

    2011-09-29

    ... recommends. In addition, we propose changing the format to make this Circular consistent with the style of... cross-referencing information related to Title VI that FTA and FHWA jointly assess and evaluate during... Title VI reporting requirements for each of these roles. We also propose cross-referencing information...

  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. Human life support during interplanetary travel and domicile. VI - Generic modular flow schematic for hybrid physical/chemical-biological life support systems

    Science.gov (United States)

    Ganapathi, Gani B.; Seshan, P. K.; Ferrall, Joseph; Rohatgi, Naresh

    1992-01-01

    An extension is proposed for the NASA Space Exploration Initiative's Generic Modular Flow Schematics for physical/chemical life support systems which involves the addition of biological processes. The new system architecture includes plant, microbial, and animal habitat, as well as the human habitat subsystem. Major Feedstock Production and Food Preparation and Packaging components have also been incorporated. Inedible plant, aquaculture, microbial, and animal solids are processed for recycling.

  9. Population.

    Science.gov (United States)

    International Planned Parenthood Federation, London (England).

    In an effort to help meet the growing interest and concern about the problems created by the rapid growth of population, The International Planned Parenthood Federation has prepared this booklet with the aim of assisting the study of the history and future trends of population growth and its impact on individual and family welfare, national,…

  10. Crystal structure of YwpF from Staphylococcus aureus reveals its architecture comprised of a β-barrel core domain resembling type VI secretion system proteins and a two-helix pair.

    Science.gov (United States)

    Lee, Sang Jae; Lee, Kyu-Yeon; Lee, Ki-Young; Kim, Dong-Gyun; Kim, Soon-Jong; Lee, Bong-Jin

    2015-04-01

    The ywpF gene (SAV2097) of the Staphylococcus aureus strain Mu50 encodes the YwpF protein, which may play a role in antibiotic resistance. Here, we report the first crystal structure of the YwpF superfamily from S. aureus at 2.5-Å resolution. The YwpF structure consists of two regions: an N-terminal core β-barrel domain that shows structural similarity to type VI secretion system (T6SS) proteins (e.g., Hcp1, Hcp3, and EvpC) and a C-terminal two-helix pair. Although the monomer structure of S. aureus YwpF resembles those of T6SS proteins, the dimer/tetramer model of S. aureus YwpF is distinct from the functionally important hexameric ring of T6SS proteins. We therefore suggest that the S. aureus YwpF may have a different function compared to T6SS proteins. © 2015 Wiley Periodicals, Inc.

  11. 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.

  12. Criminal Justice Systems. Block I: Law Enforcement. Block II: The Courts. Block III: Corrections. Block IV: Community Relations. Block V: Proficiency Skills. Block VI: Criminalistics. Student Guide.

    Science.gov (United States)

    Florida State Dept. of Education, Tallahassee. Div. of Vocational, Adult, and Community Education.

    This student guide together with an instructor guide comprise a set of curriculum materials on the criminal justice system. The student guide contains self-contained instructional material that students can study at their own pace most of the time. Six major subject areas or blocks, which are further broken down into several units, with some units…

  13. Criminal Justice Systems. Block I: Law Enforcement. Block II: The Courts. Block III: Corrections. Block IV: Community Relations. Block V: Proficiency Skills. Block VI: Criminalistics. Instructor Guide.

    Science.gov (United States)

    Florida State Dept. of Education, Tallahassee. Div. of Vocational, Adult, and Community Education.

    This instructor guide together with a student guide comprise a set of curriculum materials on the criminal justice system. The instructor guide is a resource for planning and managing individualized, competency-based instruction in six major subject areas or blocks, which are further broken down into several units with some units having several…

  14. Nuisance Source Population Modeling for Radiation Detection System Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Sokkappa, P; Lange, D; Nelson, K; Wheeler, R

    2009-10-05

    A major challenge facing the prospective deployment of radiation detection systems for homeland security applications is the discrimination of radiological or nuclear 'threat sources' from radioactive, but benign, 'nuisance sources'. Common examples of such nuisance sources include naturally occurring radioactive material (NORM), medical patients who have received radioactive drugs for either diagnostics or treatment, and industrial sources. A sensitive detector that cannot distinguish between 'threat' and 'benign' classes will generate false positives which, if sufficiently frequent, will preclude it from being operationally deployed. In this report, we describe a first-principles physics-based modeling approach that is used to approximate the physical properties and corresponding gamma ray spectral signatures of real nuisance sources. Specific models are proposed for the three nuisance source classes - NORM, medical and industrial. The models can be validated against measured data - that is, energy spectra generated with the model can be compared to actual nuisance source data. We show by example how this is done for NORM and medical sources, using data sets obtained from spectroscopic detector deployments for cargo container screening and urban area traffic screening, respectively. In addition to capturing the range of radioactive signatures of individual nuisance sources, a nuisance source population model must generate sources with a frequency of occurrence consistent with that found in actual movement of goods and people. Measured radiation detection data can indicate these frequencies, but, at present, such data are available only for a very limited set of locations and time periods. In this report, we make more general estimates of frequencies for NORM and medical sources using a range of data sources such as shipping manifests and medical treatment statistics. We also identify potential data sources for industrial

  15. The O VI Mystery: Mismatch between X-Ray and UV Column Densities

    Science.gov (United States)

    Mathur, S.; Nicastro, F.; Gupta, A.; Krongold, Y.; McLaughlin, B. M.; Brickhouse, N.; Pradhan, A.

    2017-12-01

    The UV spectra of Galactic and extragalactic sightlines often show O VI absorption lines at a range of redshifts, and from a variety of sources from the Galactic circumgalactic medium to active galactic nuclei (AGN) outflows. Inner shell O VI absorption is also observed in X-ray spectra (at λ =22.03 Å), but the column density inferred from the X-ray line was consistently larger than that from the UV line. Here we present a solution to this discrepancy for the z = 0 systems. The O II Kβ line {}4{S}0\\to {(}3D)3{p}4P at 562.40 eV (≡22.04 Å) is blended with the O VI Kα line in X-ray spectra. We estimate the strength of this O II line in two different ways, and show that in most cases the O II line accounts for the entire blended line. The small amount of O VI equivalent width present in some cases has column density entirely consistent with the UV value. This solution to the O VI discrepancy, however, does not apply to high column-density systems like AGN outflows. We discuss other possible causes to explain their UV/X-ray mismatch. The O VI and O II lines will be resolved by gratings on board the proposed mission Arcus and the concept mission Lynx, and would allow the detection of weak O VI lines not just at z = 0, but also at higher redshift.

  16. Influence of soil minerals on chromium(VI reduction by sulfide under anoxic conditions

    Directory of Open Access Journals (Sweden)

    Kim Chulsung

    2007-04-01

    Full Text Available Abstract The effects of soil minerals on chromate (CrVIO42-, noted as Cr(VI reduction by sulfide were investigated in the pH range of 7.67 to 9.07 under the anoxic condition. The examined minerals included montmorillonite (Swy-2, illite (IMt-2, kaolinite (KGa-2, aluminum oxide (γ-Al2O3, titanium oxide (TiO2, P-25, primarily anatase, and silica (SiO2. Based on their effects on Cr(VI reduction, these minerals were categorized into three groups: (i minerals catalyzing Cr(VI reduction – illite; (ii minerals with no effect – Al2O3; and (iii minerals inhibiting Cr(VI reduction- kaolinite, montmorillonite, SiO2 and TiO2 . The catalysis of illite was attributed primarily to the low concentration of iron solubilized from the mineral, which could accelerate Cr(VI reduction by shuttling electrons from sulfide to Cr(VI. Additionally, elemental sulfur produced as the primary product of sulfide oxidation could further catalyze Cr(VI reduction in the heterogeneous system. Previous studies have shown that adsorption of sulfide onto elemental sulfur nanoparticles could greatly increase sulfide reactivity towards Cr(VI reduction. Consequently, the observed rate constant, kobs, increased with increasing amounts of both iron solubilized from illite and elemental sulfur produced during the reaction. The catalysis of iron, however, was found to be blocked by phenanthroline, a strong complexing agent for ferrous iron. In this case, the overall reaction rate at the initial stage of reaction was pseudo first order with respect to Cr(VI, i.e., the reaction kinetics was similar to that in the homogeneous system, because elemental sulfur exerted no effect at the initial stage prior to accumulation of elemental sulfur nanoparticles. In the suspension of kaolinite, which belonged to group (iii, an inhibitive effect to Cr(VI reduction was observed and subsequently examined in more details. The inhibition was due to the sorption of elemental sulfur onto kaolinite, which

  17. Chromium(VI) Bioremoval by Pseudomonas Bacteria: Role of Microbial Exudates for Natural Attenuation and Biotreatment of Cr(VI) Contamination

    Energy Technology Data Exchange (ETDEWEB)

    N Mercan Dogan; C Kantar; S Gulcan; C Dodge; B Coskun Yilmaz; M Ali Mazmanci

    2011-12-31

    Laboratory batch and column experiments were conducted to investigate the role of microbial exudates, e.g., exopolymeric substance (EPS) and alginic acid, on microbial Cr(VI) reduction by two different Pseudomonas strains (P. putida P18 and P. aeuroginosa P16) as a method for treating subsurface environment contaminated with Cr(VI). Our results indicate that microbial exudates significantly enhanced microbial Cr(VI) reduction rates by forming less toxic and highly soluble organo-Cr(III) complexes despite the fact Cr(III) has a very low solubility under the experimental conditions studied (e.g., pH 7). The formation of soluble organo-Cr(III) complexes led to the protection of the cells and chromate reductases from inactivation. In systems with no organic ligands, soluble organo-Cr(III) end products were formed between Cr(III) and the EPS directly released by bacteria due to cell lysis. Our results also provide evidence that cell lysis played an important role in microbial Cr(VI) reduction by Pseudomonas bacteria due to the release of constitutive reductases that intracellularly and/or extracellularly catalyzed the reduction of Cr(VI) to Cr(III). The overall results highlight the need for incorporation of the release and formation of organo-Cr(III) complexes into reactive transport models to more accurately design and monitor in situ microbial remediation techniques for the treatment of subsurface systems contaminated with Cr(VI).

  18. Chromium(VI) bioremoval by pseudomonas bacteria: role of microbial exudates for natural attenuation and biotreatment of Cr(VI) contamination

    Energy Technology Data Exchange (ETDEWEB)

    Dogan, N.M.; Dodge, C.; Kantar, C.; Gulcan, S.; Yilmaz, B.C.; Mazmanci, M.A.

    2011-02-14

    Laboratory batch and column experiments were conducted to investigate the role of microbial exudates, e.g., exopolymeric substance (EPS) and alginic acid, on microbial Cr(VI) reduction by two different Pseudomonas strains (P. putida P18 and P. aeuroginosa P16) as a method for treating subsurface environment contaminated with Cr(VI). Our results indicate that microbial exudates significantly enhanced microbial Cr(VI) reduction rates by forming less toxic and highly soluble organo-Cr(III) complexes despite the fact Cr(III) has a very low solubility under the experimental conditions studied (e.g., pH 7). The formation of soluble organo-Cr(III) complexes led to the protection of the cells and chromate reductases from inactivation. In systems with no organic ligands, soluble organo-Cr(III) end products were formed between Cr(III) and the EPS directly released by bacteria due to cell lysis. Our results also provide evidence that cell lysis played an important role in microbial Cr(VI) reduction by Pseudomonas bacteria due to the release of constitutive reductases that intracellularly and/or extracellularly catalyzed the reduction of Cr(VI) to Cr(III). The overall results highlight the need for incorporation of the release and formation of organo-Cr(III) complexes into reactive transport models to more accurately design and monitor in situ microbial remediation techniques for the treatment of subsurface systems contaminated with Cr(VI).

  19. 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.

  20. Population growth and environment as a self-organizing system

    Directory of Open Access Journals (Sweden)

    Peter M. Allen

    1999-01-01

    Full Text Available Over recent years a new understanding of complex systems, and their dynamics and evolution has emerged, and these have been shown to provide a new basis for models of the changing patterns of population and economic activities that shape the landscape. In this paper we make clear the necessarily partial description that any particular model must provide, and show the importance of a multidisciplinary, holistic understanding, linking any particular model to the co-evolution of its environment. In addition, we show how evolutionary processes link the microscopic level of molecules through successive scales of structure and organization ultimately to the biosphere itself, to issues of climatic change, of biomes at the continental scale and atmospheric and oceanic circulation patterns. Some very recent results will be shown which demonstrate that the world climate has already been modified considerably by human activities, particularly agriculture, underlining the vital need to understand better the on-going interaction between human activities and the biosphere.

  1. Resupply Mechanism to a Contaminated Aquifer: A Laboratory Study of U(VI) Desorption from Capillary Fringe Sediments

    International Nuclear Information System (INIS)

    Um, Wooyong; Zachara, John M.; Liu, Chongxuan; Moore, Dean A.; Rod, Kenton A.

    2010-01-01

    Contaminated capillary fringe sediments are believed to function as long term source of U(VI) to Hanford's 300 Area groundwater uranium plume that discharges to the Columbia River. The deep vadose zone at this site experiences seasonal water table elevation and water compositional changes in response to Columbia River stage. Batch and column desorption experiments of U(VI) were performed on two mildly contaminated sediments from this system that vary in hydrologic position to ascertain their U(VI) release behavior and factors controlling it. Solid phase characterization of the sediments was performed to identify mineralogic and chemical factors controlling U(VI) desorption. The desorption behavior of U(VI) was different from the two sediments in spite of similar chemical and textural characteristics, and non-carbonate mineralogy. Adsorption strength and sorbed U(VI) lability was higher in the near-river sediment 11D. Inland sediment 39B displayed low sorbed U(VI) lability (∼ 10%) and measurable solid-phase carbonate content. Kinetic desorption was observed that was attributed to regeneration of labile U(VI) in 11D, and carbonate mineral dissolution in 39B. The desorption reaction was best described as an equilibrium surface complexation reaction. The noted differences in desorption behavior appear to result from U(VI) contamination and hydrologic history, as well as sediment carbonate content. Insights are provided on the dynamic adsorption/desorption behavior of contaminants in linked groundwater-river systems.

  2. DNA-PCR systems TH01 and VWA31: population data from Albania and Romania.

    Science.gov (United States)

    Huckenbeck, W; Schmidt, H D; Scheil, H G; Scheffrahn, W

    2000-06-01

    The microsatellite systems TH01 and VWA31 have been typed and analyzed for three populations from Albania (city population of Tirana, and Aromuns from a small-sized village, named Andon Poci, near Gjirokaster) and Romania (city population of Constanta). The genetic data have been compared with other, particularly South-Eastern European population.

  3. vi and Vim Editors Pocket Reference Support for every text editing task

    CERN Document Server

    Robbins, Arnold

    2011-01-01

    Many Unix, Linux, and Mac OS X geeks enjoy using the powerful, platform-agnostic text editors vi and Vim, but there are far too many commands for anyone to remember. Author Arnold Robbins has chosen the most valuable commands for vi, Vim, and vi's main clones-vile, elvis, and nvi-and packed them into this easy-to-browse pocket reference. You'll find commands for all kinds of editing tasks, such as programming, modifying system files, and writing and marking up articles. This second edition includes: Command-line optionsvi commands and set optionsInput mode shortcutsSubstitution and regular e

  4. Introduction to Individual Contribution by the VI Scientific and Professional Conferences with International Participation Geodesy, Cartography and Geographic Information Systems 2010

    Directory of Open Access Journals (Sweden)

    Janka Sabová

    2011-12-01

    Full Text Available This contribution contains a selection of articles from 6th Scientific Conference with International Participation "Geodesy,Cartography and Geographical Information Systems 2010". Particular articles are focused on the field of geodesy, engineeringsurveying, mining surveying, deformation analysis, digital photogrammetry, cartography, cadastre of real estates and terrestrial laserscanning. The reader will become familiar with the recent trends and results of research that have been achieved in these areasat universities, as well as in the commercial sector that act in branch of geodesy in the Czech and Slovak Republic.

  5. Nuclear proliferation and civilian nuclear power. Report of the Nonproliferation Alternative Systems Assessment Program. Volume VI. Safety and environmental considerations for licensing

    International Nuclear Information System (INIS)

    1980-06-01

    This volume of the Nonproliferation Alternative Systems Assessment Program report addresses safety and environmental considerations in licensing the principal alternative nuclear reactors and fuel cycles in the United States for large-scale commercial nuclear power plants. In addition, this volume examines the safety and environmental considerations for licensing fuel service centers. These centers, which have been proposed for controlling sensitive fuel-cycle facilities and special nuclear materials, would contain a combination of such facilities as reprocessing plants, fabrication plants, and reactors. For this analysis, two fuel service center concepts were selected - one with power - generating capability and one without

  6. Zodiacal Exoplanets in Time (ZEIT). VI. A Three-planet System in the Hyades Cluster Including an Earth-sized Planet

    Science.gov (United States)

    Mann, Andrew W.; Vanderburg, Andrew; Rizzuto, Aaron C.; Kraus, Adam L.; Berlind, Perry; Bieryla, Allyson; Calkins, Michael L.; Esquerdo, Gilbert A.; Latham, David W.; Mace, Gregory N.; Morris, Nathan R.; Quinn, Samuel N.; Sokal, Kimberly R.; Stefanik, Robert P.

    2018-01-01

    Planets in young clusters are powerful probes of the evolution of planetary systems. Here we report the discovery of three planets transiting EPIC 247589423, a late-K dwarf in the Hyades (≃800 Myr) cluster, and robust detection limits for additional planets in the system. The planets were identified from their K2 light curves as part of our survey of young clusters and star-forming regions. The smallest planet has a radius comparable to Earth ({0.99}-0.04+0.06{R}\\oplus ), making it one of the few Earth-sized planets with a known, young age. The two larger planets are likely a mini-Neptune and a super-Earth, with radii of {2.91}-0.10+0.11{R}\\oplus and {1.45}-0.08+0.11{R}\\oplus , respectively. The predicted radial velocity signals from these planets are between 0.4 and 2 m s-1, achievable with modern precision RV spectrographs. Because the target star is bright (V = 11.2) and has relatively low-amplitude stellar variability for a young star (2-6 mmag), EPIC 247589423 hosts the best known planets in a young open cluster for precise radial velocity follow-up, enabling a robust test of earlier claims that young planets are less dense than their older counterparts.

  7. Systemic lupus erythematosus in three ethnic groups. VI: Factors associated with fatigue within 5 years of criteria diagnosis. LUMINA Study Group. LUpus in MInority populations: NAture vs Nurture.

    Science.gov (United States)

    Zonana-Nacach, A; Roseman, J M; McGwin, G; Friedman, A W; Baethge, B A; Reveille, J D; Alarcón, G S

    2000-01-01

    To determine the frequency, degree and associated features of fatigue among Hispanic (H), African American (AA) and Caucasian (C) patients with recent onset (NAture vs Nurture) cohort were studied. Fatigue [Fatigue Severity Scale (FSS)] was defined as present if FSS score > or = 3.0. Variables from functional, clinical, sociodemographic, health behaviors, behavioral and psychological and immunogenetics domains were ascertained at study entry. Associations were examined using regression models. Eighty-six percent (85.7%) of patients reported having fatigue (82.6% H; 85.5% AA; 88.7% C); median FSS score, 5.3. Factors from the psychological and clinical domains were primarily associated with FSS; immunogenetic (HLA Class II phenotypes) features were not. Increased fatigue was strongly associated with decreasing function, both physical and mental. Variables associated with significantly greater degree of fatigue at baseline in the multivariable stepwise model in order of decreasing additional partial R2 explained included: abnormal illness-related behaviors, older age, higher self-reported pain, greater degree of helplessness, greater disease activity, Caucasian race, and lacking health insurance (model R2 = 37%). Fatigue is one of the most prevalent clinical manifestations of SLE across all ethnic groups. The perception of fatigue severity in SLE may be multifactorial in origin, including psychosocial factors and disease activity. If these prove causal, knowledge of their contribution may suggest therapeutic and/or behavioral interventions, which could ameliorate this pervasive and often incapacitating symptom of SLE.

  8. Applications of Ferrate(VI) to Wastewater Reclamation and Water Treatment

    Science.gov (United States)

    Kim, H.; Choi, H.; Lee, K.; Nam, J.; Kim, I.

    2010-12-01

    The estimated amount of water resources is about 63 billion cubic meters in Korea. However, due to the lack of precipitation during the dry season, natural flows are not enough for the water supply. In addition, since the lack of water affects water quality, environmental problems are occurred in natural and social systems. In this study, we investigated the application feasibility of ferrate(VI) systems to water and wastewater treatment. And we'd like to suggest an alternative solution for conservation and efficient reuse of the limited water resources. In the research area of environmental applications, a primary interest has been focused to the power of ferrate(VI) systems in the decomposition of pollutants in wastewater and industrial effluents due to its potential use as a strong, relatively non-toxic, and oxidizing agent for diverse environmental contaminants. Also ferrate(VI) has additional advantages as a very efficient coagulant and a sorbent of pollutants. We have analysed and compared several ferrate(VI) manufacturing processes, especially focused on the electro chemical methods(Fig. 1). And we have investigated the applications of the manufactured ferrate(VI) in our own laboratory and the commercial ferrate(VI) to decomposition of persistent organic pollutants in water. Under optimal conditions, the removal efficiencies of 2-chlorophenol and benzothiophene were above 90%(Fig. 2). The ferrate system(VI) is promising and can be one of the most efficient alternatives among the advanced oxidation processes(AOPs) for degradation of persistent organic pollutants, and is an innovative technology for the wastewater reclamation, water reusing systems, and water treatment systems. Fig 1. Comparison of Electro-Chemical Ferrate(VI) manufacturing Processes Fig 2. Degradation of 2-Chlorophenol and Bezothiophene by Ferrate. (Experimental Conditions : 2-CP = 3ppm, BT = 5ppm, NaClO4 = 0.05M)

  9. National legal system in relation to vulnerable population groups

    Directory of Open Access Journals (Sweden)

    Sjeničić Marta

    2015-01-01

    Full Text Available Vulnerable social groups can be recognized in everyday life, and local legal regulations identify them as well. Strategies and laws clearly identify the increased needs of vulnerable groups. Local legislation, for example, observes comparative law trends and attempts to prevent discrimination of persons with disabilities, emphasizes their human rights and creates the legal framework for taking these persons out of the institutional form of protection and including them into the community. In Serbia however, strategies and laws, as well as by-laws, are written in sectors, and not in cross-sectors manner. Proper caring for persons with disabilities, including persons with mental disabilities, requires an integral approach, namely a mutual approach of the social, health, educational and other sectors. True enough, local regulations stress the need for an intersectional approach, but such an approach is scantily applied in practice, so the comprehensive care that would satisfy the multiple needs of persons with mental disabilities often turns out to be less than expected in the community. Pursuant to national laws and basic ethic principals, all citizens of the Republic of Serbia have the right to health protection without discrimination. Therefore, methods for using health protection, easier than the existing ones, should be found for certain vulnerable groups, depending on their characteristics, and so for the Roma as well, and bearing in mind that systemic health regulations in Serbia open the door to special treatment of these groups. The inaccessible approach to health care of the Roma population persists primarily due to insufficient basic health documentation and basic personal documentation. Personal documents are linked with the registered place of residence, which the Roma, largely do not have. The problem is thus on a wider scale and is not only focused on the health sector. As such, it requires a wider, intersectional approach and a

  10. THE SURPRISINGLY CONSTANT STRENGTH OF O VI ABSORBERS OVER COSMIC TIME

    International Nuclear Information System (INIS)

    Fox, Andrew J.

    2011-01-01

    O VI absorption is observed in a wide range of astrophysical environments, including the local interstellar medium, the disk and halo of the Milky Way, high-velocity clouds, the Magellanic Clouds, starburst galaxies, the intergalactic medium (IGM), damped Lyα systems, and gamma-ray-burst host galaxies. Here, a new compilation of 775 O VI absorbers drawn from the literature is presented, all observed at high resolution (instrumental FWHM ≤ 20 km s -1 ) and covering the redshift range z = 0-3. In galactic environments [log N(H I) ∼> 20], the mean O VI column density is shown to be insensitive to metallicity, taking a value log N(O VI) ∼ 14.5 for galaxies covering the range -1.6 ∼ 4 K) clouds and hot (∼10 6 K) plasma, although many such layers would have to be intersected by a typical galaxy-halo sight line to build up the characteristic galactic N(O VI). The alternative, widely used model of single-phase photoionization for intergalactic O VI is ruled out by kinematic evidence in the majority of IGM O VI components at low and high redshift.

  11. Inner and inter population structure construction of Chinese Jiangsu Han population based on Y23 STR system.

    Directory of Open Access Journals (Sweden)

    Huipin Wang

    Full Text Available In this study, we analyzed the genetic polymorphisms of 23 Y-STR loci from PowerPlex® Y23 system in 916 unrelated healthy male individuals from Chinese Jiangsu Han, and observed 912 different haplotypes including 908 unique haplotypes and 4 duplicate haplotypes. The haplotype diversity reached 0.99999 and the discrimination capacity and match probability were 0.9956 and 0.0011, respectively. The gene diversity values ranged from 0.3942 at DYS438 to 0.9607 at DYS385a/b. Population differentiation within 10 Jiangsu Han subpopulations were evaluated by RST values and visualized in Neighbor-Joining trees and Multi-Dimensional Scaling plots as well as population relationships between the Jiangsu Han population and other 18 Eastern Asian populations. Such results indicated that the 23 Y-STR loci were highly polymorphic in Jiangsu Han population and played crucial roles in forensic application as well as population genetics. For the first time, we reported the genetic diversity of male lineages in Jiangsu Han population at a high-resolution level of 23 Y-STR set and consequently contributed to familial searching, offender tracking, and anthropology analysis of Jiangsu Han population.

  12. Genetics Home Reference: mucopolysaccharidosis type VI

    Science.gov (United States)

    ... on PubMed Garrido E, Chabás A, Coll MJ, Blanco M, Domínguez C, Grinberg D, Vilageliu L, Cormand B. Identification of the molecular defects in Spanish and Argentinian mucopolysaccharidosis VI (Maroteaux- ...

  13. Rheology of water ices V and VI

    Science.gov (United States)

    Durham, W.B.; Stern, L.A.; Kirby, S.H.

    1996-01-01

    We have measured the mechanical strength (??) of pure water ices V and VI under steady state deformation conditions. Constant displacement rate compressional tests were conducted in a gas apparatus at confining pressures from 400 250 K. Ices V and VI are thus Theologically distinct but by coincidence have approximately the same strength under the conditions chosen for these experiments. To avoid misidentification, these tests are therefore accompanied by careful observations of the occurrences and characteristics of phase changes. One sample each of ice V and VI was quenched at pressure to metastably retain the high-pressure phase and the acquired deformation microstructures; X ray diffraction analysis of these samples confirmed the phase identification. Surface replicas of the deformed and quenched samples suggest that ice V probably deforms largely by dislocation creep, while ice VI deforms by a more complicated process involving substantial grain size reduction through recrystallization.

  14. Adsorption of chromium(VI) on pomace-An olive oil industry waste: Batch and column studies

    International Nuclear Information System (INIS)

    Malkoc, Emine; Nuhoglu, Yasar; Dundar, Murat

    2006-01-01

    The waste pomace of olive oil factory (WPOOF) was tested for its ability to remove chromium(VI) from aqueous solution by batch and column experiments. Various thermodynamic parameters, such as ΔG o , ΔH o and ΔS o have been calculated. The thermodynamics of chromium(VI) ion onto WPOOF system indicates spontaneous and endothermic nature of the process. The ability of WPOOF to adsorb chromium(VI) in a fixed bed column was investigated, as well. The effect of operating parameters such as flow rate and inlet metal ion concentration on the sorption characteristics of WPOOF was investigated. The longest breakthrough time and maximum of Cr(VI) adsorption is obtained at pH 2.0. The total adsorbed quantities, equilibrium uptakes and total removal percents of chromium(VI) related to the effluent volumes were determined by evaluating the breakthrough curves obtained at different flow rates and different inlet chromium(VI) concentrations for adsorbent. The data confirmed that the total amount of sorbed chromium(VI) and equilibrium chromium(VI) uptake decreased with increasing flow rate and increased with increasing inlet chromium(VI) concentration. The Adams-Bohart model were used to analyze the experimental data and the model parameters were evaluated

  15. Role of Mitochondrial Electron Transport Chain Dysfunction in Cr(VI-Induced Cytotoxicity in L-02 Hepatocytes

    Directory of Open Access Journals (Sweden)

    Fang Xiao

    2014-04-01

    Full Text Available Background: Hexavalent chromium [Cr(VI] and its compounds (e.g. chromates, which are extensively used in numerous industrial processes including leather tanning and steel manufacturing, are considered as priority pollutants. There is growing evidence supporting that Cr(VI could be a human carcinogen that induces primary liver cancer after oral exposure, and this sheds light on the importance of the investigation of Cr(VI-induced hepatotoxicity. Although it is known that mitochondria are major targets for heavy metals, the mechanisms of electron transfer chain (ETC dysfunction involved in Cr(VI-induced cytotoxicity are unclear. Methods: In the present study, by using mitochondrial respiratory chain complex (MRCC I inhibitor rotenone (ROT and its substrates glutamate/malate (Glu/Mal, MRCC III inhibitor antimycin A (AA and its substrate coenzyme Q (CoQ, and the antioxidant Vitamin C (Vit C, we aimed to elucidate the role of mitochondrial ETC dysfunction in Cr(VI-induced cytotoxicity. Results: We found that Cr(VI targeted and inhibited MRCC I and III to induce ETC dysfunction, which played an important role in Cr(VI-induced cytotoxicity. Conclusion: Our current data provides novel important insight into the mechanisms of mitochondrial ETC dysfunction in Cr(VI-induced cytotoxicity in the hepatocytes, and we will be poised to develop new methods in the prevention and treatment of liver diseases involving mitochondrial ETC dysfunction for the occupational exposure population.

  16. Uranium (Vi) sorption onto zirconium diphosphate chemically modified

    Energy Technology Data Exchange (ETDEWEB)

    Garcia G, N. [Universidad Autonoma del Estado de Mexico, Facultad de Quimica, Paseo Tollocan esquina Paseo Colon s/n, Toluca 50120, Estado de Mexico (Mexico); Ordonez R, E., E-mail: nidgg@yahoo.com.m [ININ, Carretera Mexico-Toluca s/n, Ocoyoacac 52750, Estado de Mexico (Mexico)

    2010-10-15

    This work deals with the uranium (Vi) speciation after sorption onto zirconium diphosphate (ZrP{sub 2}O{sub 7}) surface, hydrated and in a surface modified with organic acids. Oxalic and citric acids were chosen to modify the ZrP{sub 2}O{sub 7} surface because they have poly carboxylic groups and they mimic the organic matter in nature. Thus the interest of this work is to evaluate the uranium (Vi) sorption edge at different s ph values in natural and modified surfaces. The luminescence technique (fluorescence and phosphorescence, respectively) was used for the quantification and speciation of uranyl sorbed at the zirconium diphosphate interface. The fluorescence experiment, showed that adsorption of uranyl on surface of zirconium diphosphate tends to 100%. The speciation shows that there are different complexes in surface which were formed between zirconium diphosphate and uranyl, since it is produced a displacement of wavelength in fluorescence spectra of each system. (Author)

  17. 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.

  18. Uranium(VI) transport modeling: geochemical data and submodels

    International Nuclear Information System (INIS)

    Tripathi, V.S.

    1984-01-01

    Understanding the geochemical mobility of U(VI) and modeling its transport is important in several contexts including ore genesis, uranium exploration, nuclear and mill-tailings waste management, and solution mining of uranium ores. Adsorption is a major control on partitioning of solutes at the mineral/solution interface. The effect of carbonate, fluoride, and phosphate complexing on adsorption of uranium was investigated. A critical compilation of stability constants of inorganic complexes and solid compounds of U(VI) necessary for proper design of experiment and for modeling transport of uranium was prepared. The general features of U(VI) adsorption in ligand-free systems are similar to those characteristic of other hydrolyzable metal ions. The adsorption processes studied were found to be reversible. The adsorption model developed in ligand-free systems, when solution complexing is taken into account, proved remarkably successful in describing adsorption of uranium in the presence of carbonate and fluoride. The presence of phosphate caused a much smaller decrease in the extent of adsorption than expected; however, a critical reassessment of the stability of UO 2 2+ .HPO 4 2- complexes, showed that phosphato complexes, if any, are extremely weak under experimental conditions. Removal of uranium may have occurred due to precipitation of sodium uranyl phosphates in addition to adsorption

  19. Big data for population-based cancer research: the integrated cancer information and surveillance system.

    Science.gov (United States)

    Meyer, Anne-Marie; Olshan, Andrew F; Green, Laura; Meyer, Adrian; Wheeler, Stephanie B; Basch, Ethan; Carpenter, William R

    2014-01-01

    The Integrated Cancer Information and Surveillance System (ICISS) facilitates population-based cancer research by developing extensive information technology systems that can link and manage large data sets. Taking an interdisciplinary 'team science' approach, ICISS has developed data, systems, and methods that allow researchers to better leverage the power of big data to improve population health.

  20. Adaptive Dynamics, Control, and Extinction in Networked Populations

    Science.gov (United States)

    2015-07-09

    extinction . VI. CONCLUSIONS We have presented a method for predicting extinction in stochastic network systems by analyzing a pair-based proxy model...including games on networks (e.g., [40], [41]). Further, we expect that our method of continuously varying a parameter while tracking the path to extinction ...Adaptive Dynamics, Control, and Extinction in Networked Populations Ira B. Schwartz US Naval Research Laboratory Code 6792 Nonlinear System Dynamics

  1. 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

  2. Phase control of light amplification with dynamically irreversible pathways of population transfer in a Λ system

    International Nuclear Information System (INIS)

    Yuan Shi; Wu Jinhui; Gao Jinyue; Pan Chunliu

    2002-01-01

    We use the relative phase of two coherent fields for the control of light amplification with dynamically irreversible pathways of population transfer in a Λ system. The population inversion and gain with dynamically irreversible pathways of population transfer are shown as the relative phase is varied. We support our results by numerical calculation and analytical explanation

  3. Plutonium(VI) accumulation and reduction by lichen biomass: correlation with U(VI)

    International Nuclear Information System (INIS)

    Ohnuki, Toshihiko; Aoyagi, Hisao; Kitatsuji, Yoshihiro; Samadfam, Mohammad; Kimura, Yasuhiko; William Purvis, O.

    2004-01-01

    The uptake of plutonium(VI) and uranium(VI) by lichen biomass was studied in the foliose lichen Parmotrema tinctorum to elucidate the migration behavior of Pu and U in the terrestrial environment. Pu and U uptake by P. tinctorum averaged 0.040±0.010 and 0.055±0.015 g g dry -1 , respectively, after 96 h incubation with 4.0x10 -4 mol l -1 Pu solutions of pH 3, 4 and 5. SEM observations showed that the accumulated Pu is evenly distributed on the upper and lower surfaces of P. tinctorum, in contrast to U(VI), which accumulated in both cortical and medullary layers. UV/VIS absorption spectroscopy demonstrates that a fraction of Pu(VI) in the solution is reduced to Pu(V) by the organic substances released from P. tinctorum, and the accumulated Pu on the surface is reduced to Pu(IV), while U(VI) keeps the oxidation state of VI. Since the solubility of Pu(IV) hydroxides is very low, reduced Pu(VI) does not penetrate to the medullary layers, but is probably precipitated as Pu(IV) hydroxides on the cortical lichen surface. It is concluded that the uptake and reduction of Pu(VI) by lichens is important to determine the mobilization and oxidation states of Pu in the terrestrial environment

  4. Plutonium(VI) accumulation and reduction by lichen biomass: correlation with U(VI)

    Energy Technology Data Exchange (ETDEWEB)

    Ohnuki, Toshihiko E-mail: ohnuki@sparclt.tokai.jaeri.go.jp; Aoyagi, Hisao; Kitatsuji, Yoshihiro; Samadfam, Mohammad; Kimura, Yasuhiko; William Purvis, O

    2004-07-01

    The uptake of plutonium(VI) and uranium(VI) by lichen biomass was studied in the foliose lichen Parmotrema tinctorum to elucidate the migration behavior of Pu and U in the terrestrial environment. Pu and U uptake by P. tinctorum averaged 0.040{+-}0.010 and 0.055{+-}0.015 g g{sub dry}{sup -1}, respectively, after 96 h incubation with 4.0x10{sup -4} mol l{sup -1} Pu solutions of pH 3, 4 and 5. SEM observations showed that the accumulated Pu is evenly distributed on the upper and lower surfaces of P. tinctorum, in contrast to U(VI), which accumulated in both cortical and medullary layers. UV/VIS absorption spectroscopy demonstrates that a fraction of Pu(VI) in the solution is reduced to Pu(V) by the organic substances released from P. tinctorum, and the accumulated Pu on the surface is reduced to Pu(IV), while U(VI) keeps the oxidation state of VI. Since the solubility of Pu(IV) hydroxides is very low, reduced Pu(VI) does not penetrate to the medullary layers, but is probably precipitated as Pu(IV) hydroxides on the cortical lichen surface. It is concluded that the uptake and reduction of Pu(VI) by lichens is important to determine the mobilization and oxidation states of Pu in the terrestrial environment.

  5. Virtual phantom magnetic resonance imaging (ViP MRI) on a clinical MRI platform.

    Science.gov (United States)

    Saint-Jalmes, Hervé; Bordelois, Alejandro; Gambarota, Giulio

    2018-01-01

    The purpose of this study was to implement Virtual Phantom Magnetic Resonance Imaging (ViP MRI), a technique that allows for generating reference signals in MR images using radiofrequency (RF) signals, on a clinical MR system and to test newly designed virtual phantoms. MRI experiments were conducted on a 1.5 T MRI scanner. Electromagnetic modelling of the ViP system was done using the principle of reciprocity. The ViP RF signals were generated using a compact waveform generator (dimensions of 26 cm × 18 cm × 16 cm), connected to a homebuilt 25 mm-diameter RF coil. The ViP RF signals were transmitted to the MRI scanner bore, simultaneously with the acquisition of the signal from the object of interest. Different types of MRI data acquisition (2D and 3D gradient-echo) as well as different phantoms, including the Shepp-Logan phantom, were tested. Furthermore, a uniquely designed virtual phantom - in the shape of a grid - was generated; this newly proposed phantom allows for the investigations of the vendor distortion correction field. High quality MR images of virtual phantoms were obtained. An excellent agreement was found between the experimental data and the inverse cube law, which was the expected functional dependence obtained from the electromagnetic modelling of the ViP system. Short-term time stability measurements yielded a coefficient of variation in the signal intensity over time equal to 0.23% and 0.13% for virtual and physical phantom, respectively. MR images of the virtual grid-shaped phantom were reconstructed with the vendor distortion correction; this allowed for a direct visualization of the vendor distortion correction field. Furthermore, as expected from the electromagnetic modelling of the ViP system, a very compact coil (diameter ~ cm) and very small currents (intensity ~ mA) were sufficient to generate a signal comparable to that of physical phantoms in MRI experiments. The ViP MRI technique was successfully implemented on a clinical MR

  6. Sorption of Chromium (VI Using Excess Municipal Sludge

    Directory of Open Access Journals (Sweden)

    Farzaneh Mohammadi

    2014-04-01

    Full Text Available Removing or decreasing hexavalent Chromium from wastewater to the permitted levels is important due to its non-biodegradation, bioaccumulation, cancer-causing and toxic effects. In this study, biosorption of Cr(VI from aqueous solutions by Excess Active Municipal Sludge was investigated as a function of initial Chromium (VI concentration (in the range of 5-90 mg/l, initial pH (in the range of 2-8, agitation speed (in the range of 50-200 rpm, adsorbent dosage (in the range of 2-10 g/l and agitation time (in the range of 5-480 min in a batch system. The optimum conditions were found by full factorial design approach. The results showed that the equilibrium time for adsorbent is 120 minutes. Also, sorption data have a good fitness by Freundlich isotherm model and adsorption kinetic is adopted with pseudo-second order model. In batch studies, at optimum condition (90 mg/l initial concentration, pH 2, agitation speed 200 rpm and adsorbent dosage 4 g/l, the adsorption performance was about 96%; the maximum adsorption capacity was calculated about 41.69 mg of Cr/g of adsorbent. Overall, it can be concluded that Excess Active Municipal Sludge, has a good performance as a biological, biodegradable, abundant and low-cost adsorbent for the removal of Cr (VI from aqueous solutions.

  7. Implementation of MP_Lite for the VI Architecture

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Weiyi [Iowa State Univ., Ames, IA (United States)

    2001-01-01

    MP_Lite is a light weight message-passing library designed to deliver the maximum performance to applications in a portable and user friendly manner. The Virtual Interface (VI) architecture is a user-level communication protocol that bypasses the operating system to provide much better performance than traditional network architectures. By combining the high efficiency of MP_Lite and high performance of the VI architecture, they are able to implement a high performance message-passing library that has much lower latency and better throughput. The design and implementation of MP_Lite for M-VIA, which is a modular implementation of the VI architecture on Linux, is discussed in this thesis. By using the eager protocol for sending short messages, MP_Lite M-VIA has much lower latency on both Fast Ethernet and Gigabit Ethernet. The handshake protocol and RDMA mechanism provides double the throughput that MPICH can deliver for long messages. MP_Lite M-VIA also has the ability to channel-bonding multiple network interface cards to increase the potential bandwidth between nodes. Using multiple Fast Ethernet cards can double or even triple the maximum throughput without increasing the cost of a PC cluster greatly.

  8. Analysing the Influence of the Spontaneous Aneuploidy Frequency on the Cell Population System Cultivation

    Directory of Open Access Journals (Sweden)

    G. A. Nefedov

    2015-01-01

    Full Text Available The paper provides a qualitative analysis of M.S. Vinogradova's nonlinear model for dynamics of the cell population system. This system describes the stem cells cultivation in vitro under resource constraints. The system consists of two populations, namely: population of normal cells and population of abnormal cells. Resource constraints are considered as linear dependences of mitosis parameters on the normalized densities of each population.One of the key parameters that effects on the realization of the system evolution scenarios is a parameter that determines a share of the normal cells, which pass, when dividing, into population of the abnormal cells. The paper analyses both the existence conditions of the rest points and the changes of the evolution scenarios of population system with changing abovementioned parameter and other system parameters held fixed. It is shown that there is a saddle-node bifurcation in the system; the bifurcation value of the parameter is found. The paper shows the interval of parameter values in which the favorable scenarios of population system evolution are implemented. It also presents results of mathematical modeling.

  9. Synthesis and application of magnetic hydrogel for Cr(VI) removal from contaminated water

    KAUST Repository

    Tang, Samuel C N

    2010-11-01

    Many magnetic adsorbents reported in the literature, such as iron oxides, for Cr(VI) removal have been found effective only in low pH environments. Moreover, the application of polymeric hydrogels on heavy metal removal has been hindered by difficulties in separation by filtration. In this study, a magnetic cationic hydrogel was synthesized for Cr(VI) removal from contaminated water, making use of the advantages of magnetic adsorbents and polymeric hydrogels. The magnetic hydrogel was produced by imbedding 10-nm γ-Fe2O 3 nanoparticles into the polymeric matrix via radical polymerization. Characterization of the hydrogel was undertaken with Fourier transform infrared and vibrating sample magnetometer; swelling properties were tested and anionic adsorption capacity was evaluated. The magnetic hydrogel showed a superior Cr(VI) removal capacity compared to commercial products such as MIEX®. Cr(VI) removal was independent of solution pH. Results show that Cr(VI) removal kinetics was improved drastically by grinding the bulk hydrogel into powder form. At relevant concentrations, common water anions (e.g., Cl-, SO4 2-, PO4 3-) and natural organic matter did not exhibit significant inhibition of Cr(VI) adsorption onto the hydrogel. Results of vibrating sample magnetometer indicate that the magnetic hydrogel can be easily separated from treatment systems. Regeneration of the magnetic hydrogel can be easily achieved by washing the Cr(VI)-loaded hydrogel with 0.5 M NaCl solution, with a recovery rate of about 90% of Cr(VI). © Copyright 2010, Mary Ann Liebert, Inc. 2010.

  10. Singular Instantons and Painlevé VI

    Science.gov (United States)

    Muñiz Manasliski, Richard

    2016-06-01

    We consider a two parameter family of instantons, which is studied in [Sadun L., Comm. Math. Phys. 163 (1994), 257-291], invariant under the irreducible action of SU_2 on S^4, but which are not globally defined. We will see that these instantons produce solutions to a one parameter family of Painlevé VI equations (P_VI}) and we will give an explicit expression of the map between instantons and solutions to P_{VI}. The solutions are algebraic only for that values of the parameters which correspond to the instantons that can be extended to all of S^4. This work is a generalization of [Muñiz Manasliski R., Contemp. Math., Vol. 434, Amer. Math. Soc., Providence, RI, 2007, 215-222] and [Muñiz Manasliski R., J. Geom. Phys. 59 (2009), 1036-1047, arXiv:1602.07221], where instantons without singularities are studied.

  11. Effect of selected ligands on the U(VI) immobilization by zerovalent iron

    International Nuclear Information System (INIS)

    Noubactep, C.

    2006-01-01

    The effect of Cl - , CO 3 2- , EDTA, NO 2 - , NO 3 - , PO 4 3- , SO 4 2- , and humic substances (HS) on the U(VI) co-precipitation from aqueous solutions by zerovalent iron (ZVI) was investigated in the neutral pH range.Batch experiments without shaking were conducted for 14 days mostly with five different ZVI materials (15 g/l), selected ligands (10mM) and an U(VI) solution (20 mg/l, 0.084mM). Apart from Cl - , all tested ligands induced a decrease of U(VI) coprecipitation. This decrease is attributed to the surface adsorption and complexation of the ligands at the reactive sites on the surface of ZVI and their corrosion products. The decrease of U(VI) removal was not uniform with the five ZVI materials. Generally, groundwater with elevated EDTA concentration could not be remediated with the ZVI barrier technology. The response of the system on the pre-treating by two ZVI materials in 250mM HCl indicated that in situ generated corrosion products favor an irreversible U(VI) uptake. Thus for the long term performance of ZVI barrier, the iron dissolution should continue in such a way that fresh iron oxide be always available for U(VI) coprecipitation. (author)

  12. Effects of phosphate and fulvic acid on the sorption and transport of uranium(VI) on silica column

    International Nuclear Information System (INIS)

    Zhang Hongxia; Yang Chao; Tao Zuyi

    2009-01-01

    Column experiments were performed, breakthrough curves (BTCs) and displacement curves (DPCs) were obtained of uranium(VI) in the absence and presence of phosphate or fulvic acid individually and simultaneously which demonstrated the effects of phosphate and fulvic acid on the sorption and transport of U(VI) in a silica column at pH 3.7 and U(VI) concentration of 5 x 10 -6 mol/L. It was found that in the presence of phosphate or fulvic acid sorbed preliminarily on the silica column, the amount of U(VI) sorbed increased significantly and the transport of U(VI) delayed significantly relative to that in the absence of phosphate or fulvic acid. Moreover, in the presence of phosphate and fulvic acids sorbed preliminarily and simultaneously on the silica column, the amount of U(VI) sorbed on the silica column is significantly increased again relative to that in the presence of phosphate or fulvic acid individually. Transport studies of U(VI) are important, since all uranium isotopes are radioactive, and uranium contamination of soils and groundwaters occurs at mining and mill sites. A fundamental understanding of the transport behavior of U(VI) in the water-mineral systems is necessary for accurate risk assessments. (author)

  13. Classification of mood disorders in DSM-V and DSM-VI.

    Science.gov (United States)

    Joyce, Peter R

    2008-10-01

    For any diagnostic system to be clinically useful, and go beyond description, it must provide an understanding that informs about aetiology and/or outcome. DSM-III and DSM-IV have provided reliability; the challenge for DSM-V and DSM-VI will be to provide validity. For DSM-V this will not be achieved. Believers in DSM-III and DSM-IV have impeded progress towards a valid classification system, so DSM-V needs to retain continuity with its predecessors to retain reliability and enhance research, but position itself to inform a valid diagnostic system by DSM-VI. This review examines the features of a diagnostic system and summarizes what is really known about mood disorders. The review also questions whether what are called mood disorders are primarily disorders of mood. Finally, it provides suggestions for DSM-VI.

  14. Cr(VI) reduction in wastewater using a bimetallic galvanic reactor

    International Nuclear Information System (INIS)

    Lugo-Lugo, Violeta; Barrera-Diaz, Carlos; Bilyeu, Bryan; Balderas-Hernandez, Patricia; Urena-Nunez, Fernando; Sanchez-Mendieta, Victor

    2010-01-01

    The electrochemical reduction of Cr(VI)-Cr(III) in wastewater by iron and copper-iron bimetallic plates was evaluated and optimized. Iron has been used as a reducing agent, but in this work a copper-iron galvanic system in the form of bimetallic plates is applied to reducing hexavalent chromium. The optimal pH (2) and ratio of copper to iron surface areas (3.5:1) were determined in batch studies, achieving a 100% reduction in about 25 min. The Cr(VI) reduction kinetics for the bimetallic system fit a first order mechanism with a correlation of 0.9935. Thermodynamic analysis shows that the Cr(VI) reduction is possible at any pH value. However, at pH values above 3.0 for iron and 5.5 for chromium insoluble species appear, indicating that the reaction will be hindered. Continuous column studies indicate that the bimetallic copper-iron galvanic system has a reduction capacity of 9.5890 mg Cr(VI) cm -2 iron, whereas iron alone only has a capacity of 0.1269 mg Cr(VI) cm -2 . The bimetallic copper-iron galvanic system is much more effective in reducing hexavalent chromium than iron alone. The exhausted plates were analyzed by SEM, EDS, and XRD to determine the mechanism and the surface effects, especially surface fouling.

  15. Fate and transport of uranium (VI) in weathered saprolite.

    Science.gov (United States)

    Kim, Young-Jin; Brooks, Scott C; Zhang, Fan; Parker, Jack C; Moon, Ji-Won; Roh, Yul

    2015-01-01

    Batch and column experiments were conducted to investigate sorption and transport of uranium (U) in the presence of saprolite derived from interbedded shale, limestone, and sandstone sequences. Sorption kinetics were measured at two initial concentrations (C0; 1, 10 μM) and three soil:solution ratios (Rs/w; 0.005, 0.25, 2 kg/L) at pH 4.5 (pH of the saprolite). The rate of U loss from solution (μmole/L/h) increased with increasing Rs/w. Uranium sorption exhibited a fast phase with 80% sorption in the first eight hours for all C0 and Rs/w values and a slow phase during which the reaction slowly approached (pseudo)equilibrium over the next seven days. The pH-dependency of U sorption was apparent in pH sorption edges. U(VI) sorption increased over the pH range 4-6, then decreased sharply at pH > 7.5. U(VI) sorption edges were well described by a surface complexation model using calibrated parameters and the reaction network proposed by Waite et al. (1994). Sorption isotherms measured using the same Rs/w and pH values showed a solids concentration effect where U(VI) sorption capacity and affinity decreased with increasing solids concentration. This effect may have been due to either particle aggregation or competition between U(VI) and exchangeable cations for sorption sites. The surface complexation model with calibrated parameters was able to predict the general sorption behavior relatively well, but failed to reproduce solid concentration effects, implying the importance of appropriate design if batch experiments are to be utilized for dynamic systems. Transport of U(VI) through the packed column was significantly retarded. Transport simulations were conducted using the reactive transport model HydroGeoChem (HGC) v5.0 that incorporated the surface complexation reaction network used to model the batch data. Model parameters reported by Waite et al. (1994) provided a better prediction of U transport than optimized parameters derived from our sorption edges. The

  16. Auris System: Providing Vibrotactile Feedback for Hearing Impaired Population

    Directory of Open Access Journals (Sweden)

    Felipe Alves Araujo

    2017-01-01

    Full Text Available Deafness, an issue that affects millions of people around the globe, is manifested in different intensities and related to many causes. This impairment negatively affects different aspects of the social life of the deaf people, and music-centered situations (concerts, religious events, etc. are obviously not inviting for them. The Auris System was conceived to provide the musical experimentation for people who have some type of hearing loss. This system is able to extract musical information from audio and create a representation for music pieces using different stimuli, a new media format to be interpreted by other senses than the hearing. In addition, the system defines a testing methodology based on a noninvasive brain activity recording using an electroencephalographic (EEG device. The results of the tests are being used to better understand the human musical cognition, in order to improve the accuracy of the Auris musical representation.

  17. Coexistence of a General Elliptic System in Population Dynamics

    DEFF Research Database (Denmark)

    Pedersen, Michael

    2004-01-01

    This paper is concerned with a strongly-coupled elliptic system representing a competitive interaction between two species. We give a sufficient condition for the existence of positive solutions. An example is also given to show that there is a coexistence of a steady state if the cross-diffusion......This paper is concerned with a strongly-coupled elliptic system representing a competitive interaction between two species. We give a sufficient condition for the existence of positive solutions. An example is also given to show that there is a coexistence of a steady state if the cross...

  18. Sibship reconstruction for inferring mating systems, dispersal and effective population size in headwater brook trout (Salvelinus fontinalis) populations

    Science.gov (United States)

    Kanno, Yoichiro; Vokoun, Jason C.; Letcher, Benjamin H.

    2011-01-01

    Brook trout Salvelinus fontinalis populations have declined in much of the native range in eastern North America and populations are typically relegated to small headwater streams in Connecticut, USA. We used sibship reconstruction to infer mating systems, dispersal and effective population size of resident (non-anadromous) brook trout in two headwater stream channel networks in Connecticut. Brook trout were captured via backpack electrofishing using spatially continuous sampling in the two headwaters (channel network lengths of 4.4 and 7.7 km). Eight microsatellite loci were genotyped in a total of 740 individuals (80–140 mm) subsampled in a stratified random design from all 50 m-reaches in which trout were captured. Sibship reconstruction indicated that males and females were both mostly polygamous although single pair matings were also inferred. Breeder sex ratio was inferred to be nearly 1:1. Few large-sized fullsib families (>3 individuals) were inferred and the majority of individuals were inferred to have no fullsibs among those fish genotyped (family size = 1). The median stream channel distance between pairs of individuals belonging to the same large-sized fullsib families (>3 individuals) was 100 m (range: 0–1,850 m) and 250 m (range: 0–2,350 m) in the two study sites, indicating limited dispersal at least for the size class of individuals analyzed. Using a sibship assignment method, the effective population size for the two streams was estimated at 91 (95%CI: 67–123) and 210 (95%CI: 172–259), corresponding to the ratio of effective-to-census population size of 0.06 and 0.12, respectively. Both-sex polygamy, low variation in reproductive success, and a balanced sex ratio may help maintain genetic diversity of brook trout populations with small breeder sizes persisting in headwater channel networks.

  19. 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.

  20. 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.

  1. Dioxouranium(VI) complexes with Schiff bases

    International Nuclear Information System (INIS)

    Birardar, N.S.; Angadi, S.D.

    1977-01-01

    Complexes of uranyl chloride with five Schiff bases have been prepared. The dioxouranium(VI) forms 1 : 2 adducts with these Schiff bases. With the help of conductivity, analytical UV, IR and NMR data, it has been shown that these complexes have coordination number eight with hexagonal bipyramid structure. (author)

  2. 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.

  3. 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 f...

  4. 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...

  5. [Population dynamics, the development of agricultural systems, and agricultural production in the densely populated rural areas of Cameroon].

    Science.gov (United States)

    Kelodjoue, S

    1989-06-01

    This comparative examination of changes in agrarian systems in 3 densely populated regions of Cameroon is intended to assess the role of demographic factors in agrarian changes and to permit prediction of future ability of the regions to continue supporting dense populations while providing a surplus for export to the rapidly growing cities. The 3 regions, Bamileke, Mont Mandaras, and the department of Lekie, are characterized by different climatic conditions, vegetation, soil types, and social organization. The total population of the 3 regions has increased from 1,278,644 in 1976 to 1,799,782 in 1987. High fertility rates seem to be the principal factor in this rapid growth. Despite very different systems of land tenure and crop regimes, the 3 areas have in common a serious lack of new lands capable of absorbing their surplus labor, and all have been greatly influenced by the introduction and spread of cash crops as their populations have come to see the land as a producer of income in addition to food, and have attempted to maximize their land holdings in conformity with their available labor and especially their desire for cash. In some areas land is no longer given to young men. Erosion and soil exhaustion are increasing. The spread of cash crops threatens the local food supply, and earnings tend to be invested in housed or wedding ceremonies rather than in increasing production. Population pressure has prompted colonization of new lands and migration to the cities or other rural areas, as well as appropriation of communal lands for private use. Conflicts over land are carried over into other areas of communal life. Underemployment of young men in some areas has led to delinquency. Efforts to intensify land use appear to be successful in the long run only where the soil is rich. Demographic pressure is a factor in the agrarian transformation of these areas, but it is only 1 of a number of factors of which the most important appears to be the entrance of the

  6. Influence of cholesterol and ceramide VI on the structure of multilamellar lipid membranes at water exchange

    International Nuclear Information System (INIS)

    Ryabova, N. Yu.; Kiselev, M. A.; Balagurov, A. M.

    2010-01-01

    The structural changes in the multilamellar lipid membranes of dipalmitoylphosphatidylcholine (DPPC)/cholesterol and DPPC/ceramide VI binary systems during hydration and dehydration have been studied by neutron diffraction. The effect of cholesterol and ceramide on the kinetics of water exchange in DPPC membranes is characterized. Compared to pure DPPC, membranes of binary systems swell faster during hydration (with a characteristic time of ∼30 min). Both compounds, ceramide VI and cholesterol, similarly affect the hydration of DPPC membranes, increasing the repeat distance due to the bilayer growth. However, in contrast to cholesterol, ceramide significantly reduces the thickness of the membrane water layer. The introduction of cholesterol into a DPPC membrane slows down the change in the parameters of the bilayer internal structure during dehydration. In the DPPC/ceramide VI/cholesterol ternary system (with a molar cholesterol concentration of 40%), cholesterol is partially released from the lamellar membrane structure into the crystalline phase.

  7. Removal of Cr(VI from Aqueous Solution Using Modified Pomegranate Peel : Equilibrium and Kinetic Studies

    Directory of Open Access Journals (Sweden)

    Tariq S. Najim

    2009-01-01

    Full Text Available The present investigation deals with the utilization of modified pomegrenate peel (MPGP and formaldehyde modified pomegrenate peel (FMPGP as adsorbents for the removal of chromium Cr(VI from aqueous solution. A series of experiments were conducted in a batch system to evaluate the effect of system variables. The effect of pH, initial Cr(VI concentration, contact time, adsorbent dosage and temperature were considered. The optimal pH values of Cr(VI removal by MPGP and FMPGP were 2.0 and 3.0 respectively. The time required for equilibrium was found to be about 100 minutes. The initial Cr(VI concentration and adsorbent dosage was found to have large effect on the adsorption of Cr(VI. The maximum uptake capacities were 13.01 and 22.28 mg of Cr(VI per gram of MPGP and FMPGP respectively. Adsorption kinetic data were tested using pseudo-first order, pseudo-second order, Elovich and intra-particle diffusion models. Kinetic studies showed that the adsorption followed a pseudo second order reaction due to the high correlation coefficient and the agreement between the experimental and calculated values of qe.The adsorption may follow intraparticle diffusion as well, due to the highest values of rate constants for the surface adsorption and intraparticle diffusion kinetic models, the higher values of rate constants are related to an improved bonding between Cr(VI ions and adsorbent particle.The Dubinin-radushkevich, Freundlich and Tempkin models were the closest fit for the equilibrium data of MPGP and FMPGP.

  8. Microbial populations causing off-flavour in recirculated aquaculture systems

    DEFF Research Database (Denmark)

    Lukassen, Mie Bech; Nielsen, Jeppe Lund; Schramm, Edward

    and are found in at least six phylogenetic groups covering 0.1% of the total community with only a minor fraction being culturable. Quantification of geoA within recirculated aquaculture systems reveals that geosmin-producing bacteria are more abundant in the water treatment compartments compared to the water......Microbial production of geosmin, a secondary metabolite with an earthy off-flavour is a serious economic problem in wine production, drinking water and aquaculture. Geosmin is produced by a small group of bacteria all harboring the geosmin synthetase gene (geoA). Sequencing and analyzing...

  9. Observations on algal populations in an experimental maturation pond system

    CSIR Research Space (South Africa)

    Shillinglaw, SN

    1977-01-01

    Full Text Available ?) of influent (HTE) and secondary pond. The arrows indicate the beginning of the noled algal concentration declines. 190 Water SA Vol. 3 No. 4 October 1977 intermittent presence of some factor which suppresses algal growth and/or removes algal cells from... the system at a very rapid rate. Another possibility is that an algal growth suppres sor is almost continuously present and only when the suppres sing factor is intermittently ahsent, do the algal concentrations exhihit a peak. Based on the results...

  10. 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) ...

  11. 77 FR 64399 - Order of Succession for HUD Region VI

    Science.gov (United States)

    2012-10-19

    ... Region VI AGENCY: Office of Field Policy and Management, HUD. ACTION: Notice of Order of Succession... its Field Offices (Region VI). This Order of Succession supersedes all previous Orders of Succession for HUD Region VI. DATES: Effective Date: October 9, 2012. FOR FURTHER INFORMATION CONTACT: Lawrence D...

  12. Validating Imaginary Worlds? The AdViSHE Assessment Tool

    Directory of Open Access Journals (Sweden)

    Paul C Langley

    2017-01-01

    Full Text Available The publication in April 2016 of the Assessment of the Validation Status of Health-Economic Decision Models (AdViSHE checklist for decision models raises a number of issues that the health technology assessment literature has yet to address. The principal issue being the role of decision models in generating claims that are evaluable and replicable. Unfortunately, this is not addressed in this new checklist which is intended to address the perceived need for a tradeoff between confidence in a decision model and the need to allocate resources by developers and payers to validating the model. Irrespective of the degree of confidence a developer or payers may have in the sufficiency of the model in representing ‘reality’ unless the model has generated evaluable claims and evidence for those claims in target treating populations, the model fails the standards of normal science. Apart from the absence of a commitment in the AdViSHE checklist to the modeling of claims that are evaluable and replicable, the validation check list makes no allowance for a product pricing strategy that may commits a manufacturer to regular and substantial annual or semi-annual product price increases. Indeed, product pricing assumptions are conspicuous by their absence. The commentary argues that failure to accommodate anticipated pricing behavior renders lifetime cost-per-QALY models and the application of willingness-to-pay thresholds meaningless.   Type: Commentary

  13. Prediction of population with Alzheimer's disease in the European Union using a system dynamics model.

    Science.gov (United States)

    Tomaskova, Hana; Kuhnova, Jitka; Cimler, Richard; Dolezal, Ondrej; Kuca, Kamil

    2016-01-01

    Alzheimer's disease (AD) is a slowly progressing neurodegenerative brain disease with irreversible brain effects; it is the most common cause of dementia. With increasing age, the probability of suffering from AD increases. In this research, population growth of the European Union (EU) until the year 2080 and the number of patients with AD are modeled. The aim of this research is to predict the spread of AD in the EU population until year 2080 using a computer simulation. For the simulation of the EU population and the occurrence of AD in this population, a system dynamics modeling approach has been used. System dynamics is a useful and effective method for the investigation of complex social systems. Over the past decades, its applicability has been demonstrated in a wide variety of applications. In this research, this method has been used to investigate the growth of the EU population and predict the number of patients with AD. The model has been calibrated on the population prediction data created by Eurostat. Based on data from Eurostat, the EU population until year 2080 has been modeled. In 2013, the population of the EU was 508 million and the number of patients with AD was 7.5 million. Based on the prediction, in 2040, the population of the EU will be 524 million and the number of patients with AD will be 13.1 million. By the year 2080, the EU population will be 520 million and the number of patients with AD will be 13.7 million. System dynamics modeling approach has been used for the prediction of the number of patients with AD in the EU population till the year 2080. These results can be used to determine the economic burden of the treatment of these patients. With different input data, the simulation can be used also for the different regions as well as for different noncontagious disease predictions.

  14. cis-dioxomolybdenum(VI)-(ONO)

    Indian Academy of Sciences (India)

    Abstract. Oxo-molybdenum chemistry is of great interest since such units are found in the active sites of a majority of molybdo-enzymes. In order to mimic the biological systems, a number of oxo-molybdenum com- plexes have been synthesised and studied. This review describes synthesis, structure and applications of oxo-.

  15. Effect of humic acid on uranium(VI) retention and transport through quartz columns with varying pH and anion type.

    Science.gov (United States)

    Du, Liang; Li, Shicheng; Li, Xiaolong; Wang, Ping; Huang, Zhaoya; Tan, Zhaoyi; Liu, Chunli; Liao, Jiali; Liu, Ning

    2017-10-01

    Humic acid (HA) 1 is ubiquitous in the environment and is an important factor in the migration behavior of U(VI) in the geological medium. The present work investigated the effect of HA on the migration behavior of U(VI) using quartz column experiments at different pH values and in the presence of various anions. The U(VI) adsorption characteristics and speciation were also studied to illuminate further the migration behavior of U(VI). Our results indicated that, at pH 6.0, HA slightly increased the migration velocity of U(VI) during the initial phase and reduced the quantity of eluted U(VI) because of the formation of HA-U(VI). The relative concentration (c/c 0 ) of U(VI)was higher in the HA-U system at pH 8.0 than that at pH 5.0 because of the higher solubility of HA in basic solutions and the difference in charge of HA-U(VI). In the U-HA-anion system at pH 6.0, the breakthrough pore volumes (PVs 2 ) of U(VI) in electrolytes containing Cl - and SO 4 2- anions (PV = 8) are much higher than for solutions containing phosphate (PV = 3), while the HA migration behavior was not significantly affected by the type of anion. Thus, the fast migration of U(VI) under HA and phosphate was attributed to phosphate rather than HA. This result suggests that phosphate should be given more attention in predictions of U(VI) migration, especially in regions with high groundwater phosphate content. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Earthworm Population Density in Sugarcane Cropping System Applied with Various Quality of Organic Matter

    OpenAIRE

    Nurhidayati, Nurhidayati; Arisoesilaningsih, Endang; Suprayogo, Didik; Hairiah, Kurniatun

    2012-01-01

    Earthworms population in the soil are greatly impacted by agricultural management, yet little is known about how the quality and quantity of organic matter addition interact in sugarcane cropping system to earthworm population. This study describes the effect of various organic matter and application rates on earthworms in sugarcane cropping system. Earthworms were collected in April, July and December from 48 experimental plots under five kinds of organic matter application : (1) cattle manu...

  17. Solid Particle Number Emission Factors of Euro VI Heavy-Duty Vehicles on the Road and in the Laboratory

    Directory of Open Access Journals (Sweden)

    Barouch Giechaskiel

    2018-02-01

    Full Text Available Particulate matter (PM, and in particular ultrafine particles, have a negative impact on human health. The contribution of vehicle PM emissions to air pollution is typically quantified with emission inventories, which need vehicle emission factors as input. Heavy-duty vehicles, although they represent a small percentage of the vehicle population in nearly every major country, contribute the majority of the on-road PM emissions. However, the published data of modern heavy-duty vehicle emissions are scarce, and for the newest Euro VI technologies, almost non-existent. The main objective of this paper is to present Solid Particle Number (SPN emission factors from Euro VI heavy-duty vehicles using diesel, Compressed Natural Gas (CNG, or Liquefied Natural Gas (LNG. Urban, rural and motorway (highway emissions were determined on the road at various European cities using SPN Portable Emission Measurement Systems (PEMS. Additional tests on a heavy-duty chassis dynamometer showed that the solid sub-23 nm fraction, which is not covered at the moment in the European regulation, is high, especially for CNG engines. The significant contribution of regeneration events and the effect of ambient temperature and engine cold-start on particle emissions were also discussed.

  18. Solid Particle Number Emission Factors of Euro VI Heavy-Duty Vehicles on the Road and in the Laboratory.

    Science.gov (United States)

    Giechaskiel, Barouch

    2018-02-09

    Particulate matter (PM), and in particular ultrafine particles, have a negative impact on human health. The contribution of vehicle PM emissions to air pollution is typically quantified with emission inventories, which need vehicle emission factors as input. Heavy-duty vehicles, although they represent a small percentage of the vehicle population in nearly every major country, contribute the majority of the on-road PM emissions. However, the published data of modern heavy-duty vehicle emissions are scarce, and for the newest Euro VI technologies, almost non-existent. The main objective of this paper is to present Solid Particle Number (SPN) emission factors from Euro VI heavy-duty vehicles using diesel, Compressed Natural Gas (CNG), or Liquefied Natural Gas (LNG). Urban, rural and motorway (highway) emissions were determined on the road at various European cities using SPN Portable Emission Measurement Systems (PEMS). Additional tests on a heavy-duty chassis dynamometer showed that the solid sub-23 nm fraction, which is not covered at the moment in the European regulation, is high, especially for CNG engines. The significant contribution of regeneration events and the effect of ambient temperature and engine cold-start on particle emissions were also discussed.

  19. Solid Particle Number Emission Factors of Euro VI Heavy-Duty Vehicles on the Road and in the Laboratory

    Science.gov (United States)

    Giechaskiel, Barouch

    2018-01-01

    Particulate matter (PM), and in particular ultrafine particles, have a negative impact on human health. The contribution of vehicle PM emissions to air pollution is typically quantified with emission inventories, which need vehicle emission factors as input. Heavy-duty vehicles, although they represent a small percentage of the vehicle population in nearly every major country, contribute the majority of the on-road PM emissions. However, the published data of modern heavy-duty vehicle emissions are scarce, and for the newest Euro VI technologies, almost non-existent. The main objective of this paper is to present Solid Particle Number (SPN) emission factors from Euro VI heavy-duty vehicles using diesel, Compressed Natural Gas (CNG), or Liquefied Natural Gas (LNG). Urban, rural and motorway (highway) emissions were determined on the road at various European cities using SPN Portable Emission Measurement Systems (PEMS). Additional tests on a heavy-duty chassis dynamometer showed that the solid sub-23 nm fraction, which is not covered at the moment in the European regulation, is high, especially for CNG engines. The significant contribution of regeneration events and the effect of ambient temperature and engine cold-start on particle emissions were also discussed. PMID:29425174

  20. ARM Airborne Carbon Measurements VI (ACME VI) Science Plan

    Energy Technology Data Exchange (ETDEWEB)

    Biraud, S [Lawrence Berkeley National Laboratory

    2015-12-01

    From October 1 through September 30, 2016, the Atmospheric Radiation Measurement (ARM) Aerial Facility will deploy the Cessna 206 aircraft over the Southern Great Plains (SGP) site, collecting observations of trace-gas mixing ratios over the ARM’s SGP facility. The aircraft payload includes two Atmospheric Observing Systems, Inc., analyzers for continuous measurements of CO2 and a 12-flask sampler for analysis of carbon cycle gases (CO2, CO, CH4, N2O, 13CO2, 14CO2, carbonyl sulfide, and trace hydrocarbon species, including ethane). The aircraft payload also includes instrumentation for solar/infrared radiation measurements. This research is supported by the U.S. Department of Energy’s ARM Climate Research Facility and Terrestrial Ecosystem Science Program and builds upon previous ARM Airborne Carbon Measurements (ARM-ACME) missions. The goal of these measurements is to improve understanding of 1) the carbon exchange at the SGP site, 2) how CO2 and associated water and energy fluxes influence radiative forcing, convective processes and CO2 concentrations over the SGP site, and 3) how greenhouse gases are transported on continental scales.

  1. Design of information systems for population data collection based on client-server at Bagolo village

    Science.gov (United States)

    Nugraha, Ucu

    2017-06-01

    Village is the level under the sub-district level in the governmental system in a region where the information system of population data service is majority provided in a manual system. However, such systems frequently lead to invalid data in addition to the available data that does not correspond to the facts as the impact of frequent errors in the process of data collection related to population including the data of the elderly and the process of data transfer. Similarly, the data correspondences such as death certificate, birth certificate, a certificate of domicile change, and so forth, have their own problems. Data archives are frequently non-systematic because they are not organized properly or not stored in a database. Nevertheless, information service system for population census at this level can assist government agencies, especially in the management of population census at the village level. A designed system can make the process of a population census easier. It is initiated by the submission of population letter by each citizen who comes to the village administrative office. Population census information system based on client-server at Bagolo Village was designed in effective and non-complicated workflow and interface design. By using the client-server as the basis, the data will be stored centrally on the server, so it can reduce data duplication and data loss. Therefore, when the local governments require data information related to the population data of a village, they can obtain it easily without the need to collect the data directly at the respective village.

  2. [Comparison of differentiated thyroid carcinoma staging systems in a Spanish population].

    Science.gov (United States)

    Andía Melero, Víctor Manuel; Martín de Santa-Olalla Llanes, María; Sambo Salas, Marcel; Percovich Hualpa, Juan Carlos; Motilla de la Cámara, Marta; Collado Yurrita, Luis

    2015-04-01

    Differentiated thyroid carcinoma staging is increasingly important due to the current trends to a less intensive therapy in low-risk patients. The TNM system is most widely used, but other systems based on follow-up of several patient cohorts have been developed. When these systems have been applied to other populations, results have been discordant. Our study evaluates the suitability of several differentiated thyroid carcinoma staging systems in a Spanish population. 729 patients with differentiated thyroid carcinoma and staging data available were enrolled. Mean follow-up time was 10.8 years. The TNM, EORTC, AMES, Clinical class, MACIS, Ohio, NTCTCS, and Spanish systems were applied to all histological types. The Kaplan-Meier survival curves for each system were analyzed, and compared using the proportion of explained variation (PEV). The demographic and clinical characteristics of our population were similar to those of other Spanish and international cohorts reported. The best systems were NTCTCS, with 74.7% PEV, and TNM (68.3%), followed by the Ohio, MACIS, EORTC, and AMES systems with minimal differences between them, while the least adequate were the Spanish (55.2%) and Clinical class (47.1%) systems. The NTCTCS staging system was found to be better than TNM in our population but, because of its simplicity and greater dissemination, the TNM appears to be recommended for staging of patients with differentiated thyroid carcinoma. Copyright © 2014 SEEN. Published by Elsevier España, S.L.U. All rights reserved.

  3. Medusa: a novel gene drive system for confined suppression of insect populations.

    Directory of Open Access Journals (Sweden)

    John M Marshall

    Full Text Available Gene drive systems provide novel opportunities for insect population suppression by driving genes that confer a fitness cost into pest or disease vector populations; however regulatory issues arise when genes are capable of spreading across international borders. Gene drive systems displaying threshold properties provide a solution since they can be confined to local populations and eliminated through dilution with wild-types. We propose a novel, threshold-dependent gene drive system, Medusa, capable of inducing a local and reversible population crash. Medusa consists of four components--two on the X chromosome, and two on the Y chromosome. A maternally-expressed, X-linked toxin and a zygotically-expressed, Y-linked antidote results in suppression of the female population and selection for the presence of the transgene-bearing Y because only male offspring of Medusa-bearing females are protected from the effects of the toxin. At the same time, the combination of a zygotically-expressed, Y-linked toxin and a zygotically-expressed, X-linked antidote selects for the transgene-bearing X in the presence of the transgene-bearing Y. Together these chromosomes create a balanced lethal system that spreads while selecting against females when present above a certain threshold frequency. Simple population dynamic models show that an all-male release of Medusa males, carried out over six generations, is expected to induce a population crash within 12 generations for modest release sizes on the order of the wild population size. Re-invasion of non-transgenic insects into a suppressed population can result in a population rebound; however this can be prevented through regular releases of modest numbers of Medusa males. Finally, we outline how Medusa could be engineered with currently available molecular tools.

  4. 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.

  5. 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?...

  6. The feasibility of BRT corridor VI shelters in Semarang City

    Science.gov (United States)

    Purnomo, Andi; Setiawan, Moch Fathoni

    2018-03-01

    Like other big cities in Indonesia, Semarang City as the capital of Central Java Province also has various city problems, one of them is the transportation problem. Transportation problems arise due to increased mobility of society that is not in balanced with the public transportation facilities and infrastructure availability. In order to create a better transportation system, the local government of Semarang City held Trans Semarang bus rapid transit (BRT) which began operating in 2010. This study aims to analyze the feasibility of BRT Trans Semarang corridor VI shelters. This research uses descriptive critique technique. The results are expected to be considered in determining the right policy in creating a better transportation system. Based on observations made, the majority of BRT Trans Semarang corridor VI uses non-permanent shelters and is less feasible to be a BRT shelter. Thus, the local government is expected to improve the feasibility of BRT Trans Semarang shelter so that the sense of security and comfort can be obtained by users of BRT. In addition, the local government is also expected to maintain the quality of services provided. These services include ticket service, the condition of buses, speed and waiting time, as well as the placement and condition of shelters.

  7. The population dynamical implications of male-biased parasitism in different mating systems.

    Directory of Open Access Journals (Sweden)

    Martin R Miller

    2007-07-01

    Full Text Available Although there is growing evidence that males tend to suffer higher levels of parasitism than females, the implications of this for the population dynamics of the host population are not yet understood. Here we build on an established 'two-sex' model and investigate how increased susceptibility to infection in males affects the dynamics, under different mating systems. We investigate the effect of pathogenic disease at different case mortalities, under both monogamous and polygynous mating systems. If the case mortality is low, then male-biased parasitism appears similar to unbiased parasitism in terms of its effect on the population dynamics. At higher case mortalities, we identified significant differences between male-biased and unbiased parasitism. A host population may therefore be differentially affected by male-biased and unbiased parasitism. The dynamical outcome is likely to depend on a complex interaction between the host's mating system and demography, and the parasite virulence.

  8. Modeling Sustainability: Population, Inequality, Consumption, and Bidirectional Coupling of the Earth and Human Systems

    Science.gov (United States)

    Motesharrei, Safa; Rivas, Jorge; Kalnay, Eugenia; Asrar, Ghassem R.; Busalacchi, Antonio J.; Cahalan, Robert F.; Cane, Mark A.; Colwell, Rita R.; Feng, Kuishuang; Franklin, Rachel S.; hide

    2016-01-01

    Over the last two centuries, the impact of the Human System has grown dramatically, becoming strongly dominant within the Earth System in many different ways. Consumption, inequality, and population have increased extremely fast, especially since about 1950, threatening to overwhelm the many critical functions and ecosystems of the Earth System. Changes in the Earth System, in turn, have important feedback effects on the Human System, with costly and potentially serious consequences. However, current models do not incorporate these critical feedbacks. We argue that in order to understand the dynamics of either system, Earth System Models must be coupled with Human System Models through bidirectional couplings representing the positive, negative, and delayed feedbacks that exist in the real systems. In particular, key Human System variables, such as demographics, inequality, economic growth, and migration, are not coupled with the Earth System but are instead driven by exogenous estimates, such as UN population projections. This makes current models likely to miss important feedbacks in the real Earth-Human system, especially those that may result in unexpected or counterintuitive outcomes, and thus requiring different policy interventions from current models. The importance and imminence of sustainability challenges, the dominant role of the Human System in the Earth System, and the essential roles the Earth System plays for the Human System, all call for collaboration of natural scientists, social scientists, and engineers in multidisciplinary research and modeling to develop coupled Earth-Human system models for devising effective science-based policies and measures to benefit current and future generations.

  9. Modeling Sustainability: Population, Inequality, Consumption, and Bidirectional Coupling of the Earth and Human Systems

    Energy Technology Data Exchange (ETDEWEB)

    Motesharrei, Safa; Rivas, Jorge; Kalnay, Eugenia; Asrar, Ghassem R.; Busalacchi, Antonio J.; Cahalan, Robert F.; Cane, Mark A.; Colwell, Rita R.; Feng, Kuishuang; Franklin, Rachel S.; Hubacek, Klaus; Miralles-Wilhelm, Fernando; Miyoshi, Takemasa; Ruth, Matthias; Sagdeev, Roald; Shirmohammadi, Adel; Shukla, Jagadish; Srebric, Jelena; Yakovenko, Victor M.; Zeng, Ning

    2016-12-11

    Over the last two centuries, the impact of the Human System has grown dramatically, becoming strongly dominant within the Earth System in many different ways. Consumption, inequality, and population have increased extremely fast, especially since about 1950, threatening to overwhelm the many critical functions and ecosystems of the Earth System. Changes in the Earth System, in turn, have important feedback effects on the Human System, with costly and potentially serious consequences. However, current models do not incorporate these critical feedbacks. We argue that in order to understand the dynamics of either system, Earth System Models must be coupled with Human System Models through bidirectional couplings representing the positive, negative, and delayed feedbacks that exist in the real systems. In particular, key Human System variables, such as demographics, inequality, economic growth, and migration, are not coupled with the Earth System but are instead driven by exogenous estimates, such as United Nations population projections. This makes current models likely to miss important feedbacks in the real Earth–Human system, especially those that may result in unexpected or counterintuitive outcomes, and thus requiring different policy interventions from current models. The importance and imminence of sustainability challenges, the dominant role of the Human System in the Earth System, and the essential roles the Earth System plays for the Human System, all call for collaboration of natural scientists, social scientists, and engineers in multidisciplinary research and modeling to develop coupled Earth–Human system models for devising effective science-based policies and measures to benefit current and future generations.

  10. 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

  11. 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.

  12. Nanomaterials based on II-VI Semiconductors

    OpenAIRE

    Cozzarini, Luca

    2012-01-01

    2010/2011 This thesis describes: (i) synthesis and characterization of colloidal nanocrystals of II-VI semiconductor compounds; (II) development of two novel materials using such nanocrystals as “building blocks”: (IIa) a nanocrystals/polymer composite, to be used as phosphor in LED-based lighting devices; (IIb) an inorganic, nano-structured multiphase material, showing a promising geometry as an electronic intermediate band material. Different typologies of nanocrystals (single-phase...

  13. Am(VI) Extraction Final Report: FY16

    Energy Technology Data Exchange (ETDEWEB)

    Mincher, Bruce Jay [Idaho National Lab. (INL), Idaho Falls, ID (United States); Grimes, Travis Shane [Idaho National Lab. (INL), Idaho Falls, ID (United States); Tillotson, Richard Dean [Idaho National Lab. (INL), Idaho Falls, ID (United States); Law, Jack Douglas [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-08-01

    This report summarizes activities related to hexavalent Am extraction for FY16, in completion of FCR&D Milestone M3FT-16IN030103027. Activities concentrated on three areas of research: 1) centrifugal contactor hot testing, 2) Am(VI) stability studies, and 3) alternative oxidant studies. A brief summary of each task follows. Hot Testing: A new engineering-scale oxidation and solvent extraction test bed was built at Idaho National Laboratory to allow for solvent extraction testing of minor actinide separation concepts. The test bed consists of an oxidation vessel, filtration apparatus, four, 3D printed, 2-cm diameter centrifugal contactors, feed/product vessels, and sample ports. This system replaced the previous 3 stage, 5-cm contactor test bed that was used for the initial testing in FY14. In the FY16 hot test, a feed simulant was spiked with 243Am and 139Ce and treated with 60 g/L sodium bismuthate for two hours to oxidize the Am(III) to Am(VI). This solution was then pumped through a filter and into the four-stage centrifugal contactor setup. The organic phase solvent formulation was 1 M diethylhexylbutyramide (DEHBA)/dodecane. The test showed that Am(VI) was produced by bismuthate oxidation and the residual oxidant was successfully filtered without back pressure buildup. Sixty-four percent of Am was extracted in the contactors using DEHBA. Both Am and Ce were quantitatively stripped by 0.1 M H2O2. Successful demonstration of the utility of small, printable contactors suggests that hot testing of separations concepts can now be conducted more often, since it is cheaper, generates less waste, and entails much less radcon risk than previous testing. Am(VI) stability: A rigorous examination of reagents was conducted to determine if contaminants could interfere with Am oxidation and extraction. An series of DAm measurements showed that bismuthate particle size, water source, acid quality, and DAAP batch or pre-treatment had little effect on extraction efficiency

  14. A spectrophotometric study of cerium IV and chromium VI species in nuclear fuel reprocessing process streams

    International Nuclear Information System (INIS)

    Nickson, I D; Boxall, C; Jackson, A; Whillock, G O H

    2010-01-01

    Nuclear fuel reprocessing schemes such as PUREX and UREX utilise HNO 3 media. An understanding of the corrosion of process engineering materials such as stainless steel in such media is a major concern for the nuclear industry. Two key species are cerium and chromium which, as Ce(IV), Cr(VI), may act as corrosion accelerants. An on-line analytical technique for these quantities would be useful for determining the relationship between corrosion rate and [Ce(IV)] and [Cr(VI)]. Consequently, a strategy for simultaneous quantification of Ce(IV), Cr(VI) and Cr(III) in the presence of other ions found in average burn-up Magnox / PWR fuel reprocessing stream (Fe, Mg, Nd, Al) is being developed. This involves simultaneous UV-vis absorbance measurement at 620, 540, 450 nm, wavelengths where Ce and Cr absorb but other ions do not. Mixed solutions of Cr(VI) and Ce(IV) are found to present higher absorbance values at 540 nm than those predicted from absorbances recorded from single component solutions of those ions. This is attributed to the formation of a 3:1 Cr(VI)-Ce(IV) complex and we report on the complexation and UV-visible spectrophotometric characteristics of this species. To the best of our knowledge this is the first experimental study of this complex in aqueous nitric acid solution systems.

  15. The natural history of glycogen storage disease types VI and IX: Long-term outcome from the largest metabolic center in Canada.

    Science.gov (United States)

    Roscher, Anne; Patel, Jaina; Hewson, Stacy; Nagy, Laura; Feigenbaum, Annette; Kronick, Jonathan; Raiman, Julian; Schulze, Andreas; Siriwardena, Komudi; Mercimek-Mahmutoglu, Saadet

    2014-11-01

    Glycogen storage disease (GSD) types VI and IX are caused by phosphorylase system deficiencies. To evaluate the natural history and long-term treatment outcome of the patients with GSD-VI and -IX, we performed an observational retrospective case study of 21 patients with confirmed diagnosis of GSD-VI or -IX. All patients with GSD-VI or -IX, diagnosed at The Hospital for Sick Children, were included. Electronic and paper charts were reviewed for clinical features, biochemical investigations, molecular genetic testing, diagnostic imaging, long-term outcome and treatment by two independent research team members. All information was entered into an Excel database. We report on the natural history and treatment outcomes of the 21 patients with GSD-VI and -IX and 16 novel pathogenic mutations in the PHKA2, PHKB, PHKG2 and PYGL genes. We report for the first time likely liver adenoma on liver ultrasound and liver fibrosis on liver biopsy specimens in patients with GSD-VI and mild cardiomyopathy on echocardiography in patients with GSD-VI and -IXb. We recommend close monitoring in all patients with GSD-VI and -IX for the long-term liver and cardiac complications. There is a need for future studies if uncooked cornstarch and high protein diet would be able to prevent long-term complications of GSD-VI and -IX. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.

  16. Preparation of graphene oxide-manganese dioxide for highly efficient adsorption and separation of Th(IV)/U(VI)

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Ning; Li, Long; Ding, Jie [College of Chemistry, Sichuan University, Chengdu 610064 (China); Li, Shengke [State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Taipa, Macau SAR (China); Wang, Ruibing, E-mail: rwang@umac.mo [State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Taipa, Macau SAR (China); Jin, Yongdong, E-mail: jinyongdong@scu.edu.cn [College of Chemistry, Sichuan University, Chengdu 610064 (China); Wang, Xiangke [School of Environment and Chemical Engineering, North China Electric Power University, Beijing 102206 (China); Xia, Chuanqin, E-mail: xiachqin@163.com [College of Chemistry, Sichuan University, Chengdu 610064 (China); Key Laboratory of Radiation Physics and Technology, Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064 (China)

    2016-05-15

    Highlights: • Simultaneous removal of Th(IV)/U(VI) by using MnO{sub 2}/GO was demonstrated. • MnO{sub 2}/GO had the highest adsorption capacity for Th(IV) and/or U(VI) than GO, MnO{sub 2}. • The selective desorption of Th(IV)/U(VI) from MnO{sub 2}/GO was evaluated. • FTIR and XPS analyses indicate the interaction between Th(IV) or U(VI) and MnO{sub 2}/GO. • XRD analysis indicates the adsorption manner of Th(IV) or U(VI) onto MnO{sub 2}/GO. - Abstract: Manganese dioxide decorated graphene oxide (GOM) was prepared via fixation of crystallographic MnO{sub 2} (α, γ) on the surface of graphene oxide (GO) and was explored as an adsorbent material for simultaneous removal of thorium/uranium ions from aqueous solutions. In single component systems (Th(IV) or U(VI)), the α-GOM{sub 2} (the weight ratio of GO/α-MnO{sub 2} of 2) exhibited higher maximum adsorption capacities toward both Th(IV) (497.5 mg/g) and U(VI) (185.2 mg/g) than those of GO. In the binary component system (Th(IV)/U(VI)), the saturated adsorption capacity of Th(IV) (408.8 mg/g)/U(VI) (66.8 mg/g) on α-GOM{sub 2} was also higher than those on GO. Based on the analysis of various data, it was proposed that the adsorption process may involve four types of molecular interactions including coordination, electrostatic interaction, cation-pi interaction, and Lewis acid-base interaction between Th(IV)/U(VI) and α-GOM{sub 2}. Finally, the Th(IV)/U(VI) ions on α-GOM{sub 2} can be separated by a two-stage desorption process with Na{sub 2}CO{sub 3}/EDTA. Those results displayed that the α-GOM{sub 2} may be utilized as an potential adsorbent for removing and separating Th(IV)/U(VI) ions from aqueous solutions.

  17. The cultural evolution of human communication systems in different sized populations: usability trumps learnability.

    Directory of Open Access Journals (Sweden)

    Nicolas Fay

    Full Text Available This study examines the intergenerational transfer of human communication systems. It tests if human communication systems evolve to be easy to learn or easy to use (or both, and how population size affects learnability and usability. Using an experimental-semiotic task, we find that human communication systems evolve to be easier to use (production efficiency and reproduction fidelity, but harder to learn (identification accuracy for a second generation of naïve participants. Thus, usability trumps learnability. In addition, the communication systems that evolve in larger populations exhibit distinct advantages over those that evolve in smaller populations: the learnability loss (from the Initial signs is more muted and the usability benefits are more pronounced. The usability benefits for human communication systems that evolve in a small and large population is explained through guided variation reducing sign complexity. The enhanced performance of the communication systems that evolve in larger populations is explained by the operation of a content bias acting on the larger pool of competing signs. The content bias selects for information-efficient iconic signs that aid learnability and enhance usability.

  18. A Trunk Support System to Identify Posture Control Mechanisms in Populations Lacking Independent Sitting.

    Science.gov (United States)

    Goodworth, Adam D; Wu, Yen-Hsun; Felmlee, Duffy; Dunklebarger, Ellis; Saavedra, Sandra

    2017-01-01

    Populations with moderate-to-severe motor control impairments often exhibit degraded trunk control and/or lack the ability to sit unassisted. These populations need more research, yet their underdeveloped trunk control complicates identification of neural mechanisms behind their movements. The purpose of this study was to overcome this barrier by developing the first multi-articulated trunk support system to identify visual, vestibular, and proprioception contributions to posture in populations lacking independent sitting. The system provided external stability at a user-specific level on the trunk, so that body segments above the level of support required active posture control. The system included a tilting surface (controlled via servomotor) as a stimulus to investigate sensory contributions to postural responses. Frequency response and coherence functions between the surface tilt and trunk support were used to characterize system dynamics and indicated that surface tilts were accurately transmitted up to 5 Hz. Feasibility of collecting kinematic data in participants lacking independent sitting was demonstrated in two populations: two typically developing infants, [Formula: see text] months, in a longitudinal study (eight sessions each) and four children with moderate-to-severe cerebral palsy (GMFCS III-V). Adaptability in the system was assessed by testing 16 adults (ages 18-63). Kinematic responses to continuous pseudorandom surface tilts were evaluated across 0.046-2 Hz and qualitative feedback indicated that the trunk support and stimulus were comfortable for all subjects. Concepts underlying the system enable both research for, and rehabilitation in, populations lacking independent sitting.

  19. Formation of solar system analogues - I. Looking for initial conditions through a population synthesis analysis

    Science.gov (United States)

    Ronco, M. P.; Guilera, O. M.; de Elía, G. C.

    2017-11-01

    Population synthesis models of planetary systems developed during the last ˜15 yr could reproduce several of the observables of the exoplanet population, and also allowed us to constrain planetary formation models. We present our planet formation model, which calculates the evolution of a planetary system during the gaseous phase. The code incorporates relevant physical phenomena for the formation of a planetary system, like photoevaporation, planet migration, gas accretion, water delivery in embryos and planetesimals, a detailed study of the orbital evolution of the planetesimal population, and the treatment of the fusion between embryos, considering their atmospheres. The main goal of this work, unlike other works of planetary population synthesis, is to find suitable scenarios and physical parameters of the disc to form Solar system analogues. We are specially interested in the final planet distributions, and in the final surface density, eccentricity and inclination profiles for the planetesimal population. These final distributions will be used as initial conditions for N-body simulations to study the post-oligarchic formation in a second work. We then consider different formation scenarios, with different planetesimal sizes and different type I migration rates. We find that Solar system analogues are favoured in massive discs, with low type I migration rates, and small planetesimal sizes. Besides, those rocky planets within their habitables zones are dry when discs dissipate. At last, the final configurations of Solar system analogues include information about the mass and semimajor axis of the planets, water contents, and the properties of the planetesimal remnants.

  20. The cultural evolution of human communication systems in different sized populations: usability trumps learnability.

    Science.gov (United States)

    Fay, Nicolas; Ellison, T Mark

    2013-01-01

    This study examines the intergenerational transfer of human communication systems. It tests if human communication systems evolve to be easy to learn or easy to use (or both), and how population size affects learnability and usability. Using an experimental-semiotic task, we find that human communication systems evolve to be easier to use (production efficiency and reproduction fidelity), but harder to learn (identification accuracy) for a second generation of naïve participants. Thus, usability trumps learnability. In addition, the communication systems that evolve in larger populations exhibit distinct advantages over those that evolve in smaller populations: the learnability loss (from the Initial signs) is more muted and the usability benefits are more pronounced. The usability benefits for human communication systems that evolve in a small and large population is explained through guided variation reducing sign complexity. The enhanced performance of the communication systems that evolve in larger populations is explained by the operation of a content bias acting on the larger pool of competing signs. The content bias selects for information-efficient iconic signs that aid learnability and enhance usability.

  1. A Population of planetary systems characterized by short-period, Earth-sized planets

    Science.gov (United States)

    Steffen, Jason H.; Coughlin, Jeffrey L.

    2016-01-01

    We analyze data from the Quarter 1–17 Data Release 24 (Q1–Q17 DR24) planet candidate catalog from NASA’s Kepler mission, specifically comparing systems with single transiting planets to systems with multiple transiting planets, and identify a population of exoplanets with a necessarily distinct system architecture. Such an architecture likely indicates a different branch in their evolutionary past relative to the typical Kepler system. The key feature of these planetary systems is an isolated, Earth-sized planet with a roughly 1-d orbital period. We estimate that at least 24 of the 144 systems we examined (≳17%) are members of this population. Accounting for detection efficiency, such planetary systems occur with a frequency similar to the hot Jupiters. PMID:27790984

  2. Investigation of the Nonlinear Model of the Cellular Population System Development

    Directory of Open Access Journals (Sweden)

    M. S. Vinogradova

    2014-01-01

    Full Text Available An isolated population system is considered which consists of two types of human stem cells: normal cells and cells with chromosomal anomalies (abnormal. In the paper the nonlinear dynamic model which describes dynamics of cell populations developing in vitro is elaborated. The model allows to investigate the processes of the formation of the abnormal cells population from the abnormal cells population of normal cells as well as joint development of these populations. The model takes into account the limited resources.An important feature of the developed model is the use of biological characteristics of processes in the cell population system, such as the proportion of cells, divided over a specified time, the proportion of cells whish are not divided, and which are "lost" and which are passed in the population of abnormal cells from the normal population. This approach allows a more detailed analysis of the impact of various "primary" parameters on the evolution of the population system.Under cultivation of cell populations in vitro a struggle for resources primarily affects the processes of the cell reproduction. This is reflected in the existence of the dividing cells frequency dependence of the total population of normal and abnormal cells. For the account of such dependencies different non-linear functions are typically used. However, the use of such non-linear relationships leads to the difficulties in finding confidence intervals for the estimates of the model parameters at subsequent stages of research. At the same time, the problem of the system parameters estimating and finding of the corresponding confidence intervals for estimates can be solved easy in case when the nonlinear system is linear with respect to the unknown parameters. In the paper it is achieved due to the piecewise linear approximation of nonlinear dependencies.An important feature of the model is a different view of the right part of the differential equations system

  3. An e-Health Platform for the Elderly Population: The Butler System

    Science.gov (United States)

    Etchemendy, E.; Banos, R. M.; Botella, C.; Castilla, D.; Alcaniz, M.; Rasal, P.; Farfallini, L.

    2011-01-01

    The Butler system is an e-health platform designed to improve the elderly population's quality of life. The Butler system has three applications diagnostic, therapeutic and playful. The objective of this work is to present the influence of the use of the platform on elderly users' mood states and the degree of acceptance. These measures were…

  4. 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

  5. Rapid thermal metalorganic chemical vapor deposition of II VI compounds

    Science.gov (United States)

    Stolyarova, S.; Amir, N.; Nemirovsky, Y.

    1998-02-01

    In this paper we analyze the potential benefits of rapid thermal processing combined with metalorganic chemical vapor deposition (RT-MOCVD) for II-VI compounds and review our first results of the application of RT-MOCVD to the growth of CdTe/CdZnTe, CdTe/HgCdTe and ZnTe/CdTe heterostructures. The RT-MOCVD growth of (1 1 1) CdTe and ZnTe was performed in the A.G. Associates Heatpulse CVD-800™ system using a horizontal quartz reactor heated from both sides by tungsten-halogen lamps. The main features of RT-MOCVD of II-VI materials are: very high growth rates (up to 60 μm/h for CdTe and 30 μm/h for ZnTe); low point defect densities in the epilayers; more abrupt interfaces and less substrate surface degradation compared to conventional MOCVD. Potential of RT-MOCVD for MCT passivation has been shown.

  6. 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.

  7. Variability of innate immune system genes in Native American populations-relationship with history and epidemiology.

    Science.gov (United States)

    Lindenau, Juliana Dal-Ri; Salzano, Francisco Mauro; Hurtado, Ana Magdalena; Hill, Kim R; Petzl-Erler, Maria Luiza; Tsuneto, Luiza Tamie; Hutz, Mara Helena

    2016-04-01

    The immune system of a host, defending him/her against invading pathogens, has two main subsystems: innate immunity and acquired immunity. There are several evidences showing that Native American populations are immunologically different from non-Native populations. Our aim was to describe the variability of innate immune system genes in Native American populations. We investigated heterozygozities and patterns of population differentiation (FST ) of 14 polymorphisms related to the innate immune response in five Native American populations (Aché, Guarani-Kaiowá, Guarani-Ñandeva, Kaingang, and Xavante) and the results were compared with the three major world population data (YRI, CEU, and CHB) available at the 1,000 genomes database. Mean heterozygosities ranged between 0.241 ± 0.057 (Aché) and 0.343 ± 0.033 (Kaingang), but no significant differences were observed (Friedman test, P = 0.197). Mean heterozygosities were also not significantly different when Amerindians were pooled and compared with the 1000 genomes populations (Friedman test, P = 0.506). When the Native American populations were grouped as Amerindians, a significantly higher FST value (0.194) was observed between the Amerindian and African populations. The Ewens-Watterson neutrality test showed that these markers are not under strong selective pressure. Native American populations present similar levels of heterozygosity as those of other continents, but are different from Africans in the frequency of polymorphisms of innate immune genes. This higher differentiation is probably due to demographic processes that occurred during the out-of-Africa event. © 2015 Wiley Periodicals, Inc.

  8. Nonlinearities Lead to Qualitative Differences in Population Dynamics of Predator-Prey Systems

    Czech Academy of Sciences Publication Activity Database

    Ameixa, Olga; Messelink, G. J.; Kindlmann, Pavel

    2013-01-01

    Roč. 8, č. 4 (2013), e62530-e62530 E-ISSN 1932-6203 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073; GA ČR(CZ) GEVOL/11/E036 Institutional support: RVO:67179843 Keywords : nonlinear system * population density * population dynamics * predator * predator prey interaction * qualitative analysis Subject RIV: EH - Ecology , Behaviour Impact factor: 3.534, year: 2013

  9. Surveys of tidal river systems in the northern territory of Australia and their crocodile populations

    Energy Technology Data Exchange (ETDEWEB)

    Vorlicek, G.C.; Messel, H.; Green, W.J.

    1986-01-01

    This book provides an update on the population dynamics of Crocodylus porous in the tidal waterways of Van Diemen Gulf and the Southern Gulf of Carpentaria, Australia, during 1984 and 1985. Contents: Prologue; Dedication; Introduction; Status of Crocodylus porous. July 1984, in the tidal waterways of the Alligator Region and in the Adelaide River System of Northern Australia: recovery underway; Resurvey of Crocodylus porous populations in the tidal waterways of the southern Gulf of Carpentaria, September - October 1985; Local knowledge - Northern Australia style.

  10. Electrochemical investigations on cation-cation interaction between Np(V) and U(VI) in nitric acid medium

    International Nuclear Information System (INIS)

    Verma, P.K.; Murali, M.S.; Pathak, P.N.; Mohapatra, P.K.

    2014-01-01

    Ever since the first report on cation-cation interactions (CCIs) in 1961 by Sullivan et al., many researchers have worked on this using different techniques like optical spectroscopy and potentiometry. However, there is almost no report, in recent times, on this interesting subject using an electrochemical technique. In the present work, we set out to use simple cyclic voltammetry (CV) as a probe to study this phenomenon in the case of Np(V)-U(VI) in nitric acid medium. Accordingly, cyclic voltammograms were recorded individually for Np(V) , U(VI) in 4M HNO 3 and for solutions resulting from a titration of Np(V) with incremental additions of U(VI) in the same medium. These experiments were carried out using AutoLab 30 with three solid electrode system. Ag/AgCl was the reference electrode while Pt wires were used as working and counter electrode. The paper gives the part of CVs for successive additions of only U(VI) (1.4M) at fixed scan rate and room temperature. It can be seen that that the reduction peak shifts only slightly towards left with increased aliquots of U(VI). In contrast, the paper also gives the part of CVs for only U(VI) and for a titration mixture of fixed concentration of Np(V) and successive volume aliquot-additions of U(VI). It can be seen that there was no appreciable shift in the cathodic peak (∼ -0.15V) for additions of 1225μL of only U(VI) and 3225 μL of U(VI) in presence of Np. This showed that no change occurred till this composition. But with the addition of next aliquot of 4225μL of U(VI), there was an appreciable shift in the peak. This signified the formation of a new complex which can be attributed to the cation-cation interaction envisaged for Np(V)-U(VI). With further addition of an aliquot of 4725 μL of U(VI), it can be seen that again there was no appreciable shift in the cathodic peak position which probably underlined that the formation of the complex was complete

  11. Enhanced Performance for Treatment of Cr (VI-Containing Wastewater by Microbial Fuel Cells with Natural Pyrrhotite-Coated Cathode

    Directory of Open Access Journals (Sweden)

    Junxian Shi

    2017-12-01

    Full Text Available Here we reported the investigation of enhanced performance for the removal of hexavalent chromium (Cr (VI by a new microbial fuel cell (MFC with natural pyrrhotite-coated cathode. By comparisons of the graphite-cathode, the MFCs equipped with a pyrrhotite-coated cathode generated the maximum power density of 45.4 mW·m−2 that was 1.3 times higher than that of with bare graphite cathode (35.5 mW·m−2. Moreover, the Cr (VI removal efficiency of 97.5% achieved after 4.5 h compared with only 46.1% by graphite cathode MFC. In addition, Cr (VI removal rate with different initial Cr (VI concentrations for 10 mg/L and 30 mg/L was investigated and a decreased removal percentage with increasing Cr (VI concentration was observed. Batches of experiments of different pH values from 3.0 to 9.0 in catholyte were carried out to optimize system performance. The complete Cr (VI removal was achieved at pH 3.0 and 99.59% of Cr (VI was removed after 10.5 h, which met the requirement of the Cr (VI National Emission Standard. When the value of pH was decreasing, the removal rate was obviously increased and Cr (VI could be removed successfully with a broad pH range indicating pyrrhotite-coated cathode MFC had more extensive usage scope. Furthermore, cathode treatment products were studied by X-ray photoelectron spectroscopy (XPS, Cr2O3, Cr (III-acetate were detected on the cathode by the XPS Cr2p spectra and no Cr (VI founded, indicating that the Cr on the surface of cathode was Cr (III and Cr (VI were reduced. On cathode, pyrrhotite not only played a significant role for catalyst of MFCs, but also acted as reactive sites for Cr (VI reduction. Our research demonstrated that pyrrhotite, an earth-abundant and low-cost natural mineral was promised as an effective cathode material. Which had great potential applications in MFCs for reduction of wastewater containing heavy metals and other environmental contaminants in the future.

  12. 40 CFR Appendix Vi to Part 86 - Vehicle and Engine Components

    Science.gov (United States)

    2010-07-01

    ... exhaust valves. (2) Drive belts. (3) Manifold and cylinder head bolts. (4) Engine oil and filter. (5.... (2) Cooling system. a. Coolant. b. Thermostat. c. Filter. (3) Lubrication. a. Oil filter. b... 40 Protection of Environment 19 2010-07-01 2010-07-01 false Vehicle and Engine Components VI...

  13. VMI-VI and BG-II KOPPITZ-2 for Youth with HFASDs and Typical Youth

    Science.gov (United States)

    McDonald, Christin A.; Volker, Martin A.; Lopata, Christopher; Toomey, Jennifer A.; Thomeer, Marcus L.; Lee, Gloria K.; Lipinski, Alanna M.; Dua, Elissa H.; Schiavo, Audrey M.; Bain, Fabienne; Nelson, Andrew T.

    2014-01-01

    The visual-motor skills of 90 youth with high-functioning autism spectrum disorders (HFASDs) and 51 typically developing (TD) youth were assessed using the Beery-Buktenica Developmental Test of Visual-Motor Integration, Sixth Edition (VMI-VI) and Koppitz Developmental Scoring System for the Bender-Gestalt Test-Second Edition (KOPPITZ-2).…

  14. Assessment of substantia nigra echogenicity in German and Filipino populations using a portable ultrasound system.

    Science.gov (United States)

    Go, Criscely L; Frenzel, Antonia; Rosales, Raymond L; Lee, Lillian V; Benecke, Reiner; Dressler, Dirk; Walter, Uwe

    2012-02-01

    Transcranial sonography of the substantia nigra for diagnosing premotor stages of Parkinson disease has been attracting increasing interest. Standard reference values defining an abnormal increased echogenic size (hyperechogenicity) of the substantia nigra have been established in several populations using high-end stationary ultrasound systems. It is unknown whether a portable ultrasound system can be appropriately used and how the Filipino population would compare with the well-studied white population. We prospectively studied substantia nigra echogenic sizes and third ventricle widths in 71 healthy adult German participants and 30 age- and sex-matched Filipino participants using both a well-established stationary ultrasound system (in the German cohort) and a recently distributed portable ultrasound system (in both ethnic cohorts). Mean substantia nigra echogenic sizes, cutoff values defining abnormal hyperechogenicity, and intra-rater reliability were similar with both systems and in both ethnic cohorts studied. The Filipino and German participants did not differ with respect to the frequency of insufficient insonation conditions (each 3%) and substantia nigra hyperechogenicity (10% versus 9%; P = .80). However, third ventricle widths were smaller in the Filipino than the German participants (mean ± SD, 1.6 ± 1.1 versus 2.4 ± 1.0 mm; P = .004). The frequency of substantia nigra hyperechogenicity appears to be homogeneous in white and Asian populations. Screening for this feature may well be performed with a present-day portable ultrasound system.

  15. Population synthesis analysis: determining parameters and favorable scenarios for the formation of Solar System Analogs

    Science.gov (United States)

    Ronco, M. P.; Gulera, O. M.; de Elía, G. C.

    2017-07-01

    The primordial scenario and the initial conditions that gave rise to the Solar System are still under debate. A population synthesis analysis of the formation and evolution of Solar System Analogs (SSA) is a possible mechanism to understand our own Solar System. From a new numerical code called PlanetaLP, which is able to build a diversity of planetary systems describing the evolution of embryos and planetesimals during the gaseous phase, we determine which are the parameters of the disk and the most favorable scenarios that provide planetary systems like our own.

  16. How Academic Health Systems Can Achieve Population Health in Vulnerable Populations Through Value-Based Care: The Critical Importance of Establishing Trusted Agency.

    Science.gov (United States)

    Wesson, Donald E; Kitzman, Heather E

    2018-01-16

    Improving population health may require health systems to proactively engage patient populations as partners in the implementation of healthy behaviors as a shared value using strategies that incentivize healthy outcomes for the population as a whole. The current reactive health care model, which focuses on restoring the health of individuals after it has been lost, will not achieve the goal of improved population health. To achieve this goal, health systems must proactively engage in partnerships with the populations they serve. Health systems will need the help of community entities and individuals who have the trust of the population being served to act on behalf of the health system if they are to achieve this effective working partnership. The need for these trusted agents is particularly pertinent for vulnerable and historically underserved segments of the population. In this Invited Commentary, the authors discuss ways by which health systems might identify, engage, and leverage trusted agents to improve the health of the population through value-based care.

  17. Enhanced removal of toxic Cr(VI) in tannery wastewater by photoelectrocatalysis with synthetic TiO2 hollow spheres

    Science.gov (United States)

    Zhao, Yang; Chang, Wenkai; Huang, Zhiding; Feng, Xugen; Ma, Lin; Qi, Xiaoxia; Li, Zenghe

    2017-05-01

    Owing to the acute toxicity and mobility, the Cr(VI) in tannery wastewater is a huge threat to biological and environmental systems. Herein, an effective photoelectrocatalytic reduction of Cr(VI) was carried out by applying electric field to photocatalysis of as-prepared TiO2 spheres. The synthesis of spherical TiO2 catalytic materials with hollow structure and high surface areas was based on a self-assembly process induced by a mixture of organic acetic acid and ethanol. The possible formation mechanism of TiO2 spheres was proposed and verified by acid concentration-dependent and temperature-dependent experiments. It was found that the reaction rate constant of photoelectrocatalytic reduction of Cr(VI) exhibited an almost 3 fold improvement (0.0362 min-1) as compared to that of photocatalysis (0.0126 min-1). As a result, the mechanism of photoelectrocatalytic reduction of Cr(VI) was described according to the simultaneous determination of Cr(VI), Cr(III) and total Cr in the system. In addition, the effect of pH value and voltage of potential were also discussed. Moreover, this photoelectrocatalysis with TiO2 hollow spheres exhibited excellent activity for reduction of Cr(VI) in actual tannery wastewater produced from three different tanning procedures. These attributes suggest that this photoelectrocatalysis has strong potential applications in the treatment of tannery pollutants.

  18. Nanostructure, thermoelectric properties, and transport theory of V{sub 2}VI{sub 3} and V{sub 2}VI{sub 3}/IV-VI based superlattices and nanomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Dankwort, Torben; Schuermann, Ulrich; Kienle, Lorenz [Institute for Materials Science, Christian Albrechts University Kiel (Germany); Hansen, Anna-Lena; Bensch, Wolfgang [Institute for Inorganic Chemistry, Christian Albrechts University Kiel (Germany); Winkler, Markus; Koenig, Jan D. [Fraunhofer Institute for Physical Measurement Techniques IPM, Freiburg (Germany); Johnson, David C. [Department of Chemistry and Materials Science Institute, University of Oregon, Eugene, OR (United States); Hinsche, Nicki F. [Institute of Physics, Martin Luther University Halle-Wittenberg, Halle/Saale (Germany); Zahn, Peter [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany); Mertig, Ingrid [Institute of Physics, Martin Luther University Halle-Wittenberg, Halle/Saale (Germany); Max Planck Institute of Microstructure Physics, Halle (Germany)

    2016-03-15

    The scope of this work is to review the thermoelectric properties, the microstructures, and their correlation with theoretical calculations and predictions for recent chalcogenide based materials. The main focus is put on thin multilayered Bi{sub 2}Te{sub 3}, Sb{sub 2}Te{sub 3} films, and bulk V{sub 2}VI{sub 3}/IV-VI mixed systems. For all films a systematic characterization of the thermoelectric properties as well as the micro- and nanostructure was performed. The degree of crystallinity of the multilayered films varied from epitaxial systems to polycrystalline films. Other multilayered thin films revealed promising thermoelectric properties. (SnSe){sub 1.2}TiSe{sub 2} thin films with rotational disorder yielded the highest Seebeck coefficient published to date for analogous materials. For bulk V{sub 2}VI{sub 3}/IV-VI mixed systems insides are given into a complete ''material to module'' process resulting in a high performance thermoelectric generator using (1-x)(GeTe) x(Bi{sub 2}Se{sub 0.2}Te{sub 2.8}) (x = 0.038). Cyclic heating of this system with x = 0.063 resulted in a drastic change of the micro- and nanostructure observed by ex situ and in situ X-ray diffraction (XRD) and transmission electron microscopy (TEM). Consequently a degradation of ZT at 450 C from ∝2.0 to ∝1.0 was observed, while samples with x = 0.038 showed a stable ZT of 1.5. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  19. Uranium(VI) Binding Forms in Selected Human Body Fluids: Thermodynamic Calculations versus Spectroscopic Measurements.

    Science.gov (United States)

    Osman, Alfatih A A; Geipel, Gerhard; Barkleit, Astrid; Bernhard, Gert

    2015-02-16

    Human exposure to uranium increasingly becomes a subject of interest in many scientific disciplines such as environmental medicine, toxicology, and radiation protection. Knowledge about uranium chemical binding forms(speciation) in human body fluids can be of great importance to understand not only its biokinetics but also its relevance in risk assessment and in designing decorporation therapy in the case of accidental overexposure. In this study, thermodynamic calculations of uranium speciation in relevant simulated and original body fluids were compared with spectroscopic data after ex-situ uranium addition. For the first time, experimental data on U(VI) speciation in body fluids (saliva, sweat, urine) was obtained by means of cryogenic time-resolved laser-induced fluorescence spectroscopy (cryo-TRLFS) at 153 K. By using the time dependency of fluorescence decay and the band positions of the emission spectra, various uranyl complexes were demonstrated in the studied samples. The variations of the body fluids in terms of chemical composition, pH, and ionic strength resulted in different binding forms of U(VI). The speciation of U(VI) in saliva and in urine was affected by the presence of bioorganic ligands, whereas in sweat, the distribution depends mainly on inorganic ligands. We also elucidated the role of biological buffers, i.e., phosphate (H(2)PO(4−)/HPO(4)(2−)) on U(VI) distribution, and the system Ca(2+)/UO(2)(2+)/PO(4)(3−) was discussed in detail in both saliva and urine. The theoretical speciation calculations of the main U(VI) species in the investigated body fluids were significantly consistent with the spectroscopic data. Laser fluorescence spectroscopy showed success and reliability for direct determination of U(VI) in such biological matrices with the possibility for further improvement.

  20. ColVI myopathies: where do we stand, where do we go?

    Directory of Open Access Journals (Sweden)

    Allamand Valérie

    2011-09-01

    Full Text Available Abstract Collagen VI myopathies, caused by mutations in the genes encoding collagen type VI (ColVI, represent a clinical continuum with Ullrich congenital muscular dystrophy (UCMD and Bethlem myopathy (BM at each end of the spectrum, and less well-defined intermediate phenotypes in between. ColVI myopathies also share common features with other disorders associated with prominent muscle contractures, making differential diagnosis difficult. This group of disorders, under-recognized for a long time, has aroused much interest over the past decade, with important advances made in understanding its molecular pathogenesis. Indeed, numerous mutations have now been reported in the COL6A1, COL6A2 and COL6A3 genes, a large proportion of which are de novo and exert dominant-negative effects. Genotype-phenotype correlations have also started to emerge, which reflect the various pathogenic mechanisms at play in these disorders: dominant de novo exon splicing that enables the synthesis and secretion of mutant tetramers and homozygous nonsense mutations that lead to premature termination of translation and complete loss of function are associated with early-onset, severe phenotypes. In this review, we present the current state of diagnosis and research in the field of ColVI myopathies. The past decade has provided significant advances, with the identification of altered cellular functions in animal models of ColVI myopathies and in patient samples. In particular, mitochondrial dysfunction and a defect in the autophagic clearance system of skeletal muscle have recently been reported, thereby opening potential therapeutic avenues.

  1. Adsorption of Cr(VI) and As(V) ions by modified magnetic chitosan chelating resin.

    Science.gov (United States)

    Abou El-Reash, Y G; Otto, M; Kenawy, I M; Ouf, A M

    2011-11-01

    Cross-linked magnetic chitosan anthranilic acid glutaraldehyde Schiff's base (CAGS) was prepared for adsorption of both As(V) and Cr(VI) ions and their determination by ICP-OES. Prepared cross-linked magnetic CAGS was investigated by means of SEM, FTIR, wide angle X-ray diffraction (WAXRD) and TGA analysis. The adsorption properties of cross-linked magnetic CAGS resin toward both As(V) and Cr(VI) were evaluated. Various factors affecting the uptake behavior such as pH, temperature, contact time, initial concentration of metal ions, effect of other ions and desorption were studied. The equilibrium was achieved after about 110 min and 120 min for As(V) and Cr(VI), respectively at pH=2. The adsorption kinetics followed the mechanism of the pseudo-second order equation for all systems studied, evidencing chemical sorption as the rate-limiting step of adsorption mechanism and not involving a mass transfer in solution. The equilibrium data were analyzed using the Langmuir, Freundlich, and Tempkin isotherm models. The best interpretation for the equilibrium data was given by Langmuir isotherm, and the maximum adsorption capacities were 58.48 and 62.42 mg/g for both Cr(VI) and As(V), respectively. Cross-linked magnetic CAGS displayed higher adsorption capacity for Cr(VI). The adsorption capacity of the metal ions increased with increasing temperature under optimum conditions in case of Cr(VI), but decreased in case of As(V). The metal ion-loaded cross-linked magnetic CAGS were regenerated with an efficiency of greater than 88% using 0.2M sodium hydroxide (NaOH). Copyright © 2011 Elsevier B.V. All rights reserved.

  2. "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...

  3. Voltammetry of Os(VI)-modified polysaccharides

    Czech Academy of Sciences Publication Activity Database

    Trefulka, Mojmír; Paleček, Emil

    2010-01-01

    Roč. 22, č. 16 (2010), s. 1837-1845 ISSN 1040-0397 R&D Projects: GA AV ČR(CZ) GPP301/10/P548; GA MŠk(CZ) LC06035 Grant - others:GA AV ČR(CZ) KAN400310651 Program:KA Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : chemical modification of polysaccharides * electroactive labels * osmium(VI) complexes Subject RIV: BO - Biophysics Impact factor: 2.721, year: 2010

  4. Reduction U(VI) using jones reductor

    International Nuclear Information System (INIS)

    Simbolon, S.

    1996-01-01

    Reduction of dissolved oxide uranium in sulfuric acid use of reductor Jones Zn (Hg) was carried out. The reduced uranium sulfate solution was analyzed its U(IV) by measuring its absorbance on 652 nm and compared to oxidation U(IV) solution with KMnO 4 solution. It was found that the comparison was in a good agreement. However, measuring of absorbance of U(VI) solution on 429 nm result of oxidation U(IV) with KMnO 4 solution was not change. (author)

  5. ViPTree: the viral proteomic tree server

    OpenAIRE

    Nishimura, Yosuke; Yoshida, Takashi; Kuronishi, Megumi; Uehara, Hideya; Ogata, Hiroyuki; Goto, Susumu

    2017-01-01

    ViPTree is a web server provided through GenomeNet to generate viral proteomic trees for classification of viruses based on genome-wide similarities. Users can upload viral genomes sequenced either by genomics or metagenomics. ViPTree generates proteomic trees for the uploaded genomes together with flexibly selected reference viral genomes. ViPTree also serves as a platform to visually investigate genomic alignments and automatically annotated gene functions for the uploaded viral genomes, th...

  6. Sorption of Cr(VI) ions on two Lewatit-anion exchange resins and their quantitative determination using UV-visible spectrophotometer.

    Science.gov (United States)

    Pehlivan, E; Cetin, S

    2009-04-15

    The sorption of Cr(VI) from aqueous solutions with macroporous resins which contain quarternary amine groups (Lewatit MP 64 and Lewatit MP 500) was studied at varying Cr(VI) concentration, adsorbent dose, pH, contact time and temperature. Batch shaking sorption experiments were carried out to evaluate the performance of Lewatit MP 64 and Lewatit MP 500 anion exchange resins in the removal of Cr(VI) from aqueous solutions. The concentration of Cr(VI) in aqueous solution was determined by UV-visible spectrophotometer. The ion exchange process, which is dependent on pH, showed maximum removal of Cr(VI) in the pH range 3-7 for an initial Cr(VI) concentration of 1x10(-3) M. The optimum pH for Cr(VI) adsorption was found as 5.0 for Lewatit MP 64 and 6.0 for Lewatit MP 500. The maximum Cr(VI) adsorption at pH 5.0 is 0.40 and 0.41 mmol/g resin for Lewatit MP 64 and Lewatit MP 500 anion exchangers, respectively. The maximum chromium sorption occurred at approximately 60 min for Lewatit MP 64 and 75 min for Lewatit MP 500. The suitability of the Freundlich and Langmuir adsorption models was also investigated for each chromium-sorbent system. The uptake of Cr(VI) by the anion exchange resins was reversible and so it has good potential for the removal of Cr(VI) from aqueous solutions. Both ion exchangers had high bonding constants but Lewatit MP 500 showed stronger binding. The rise in the temperature caused a slight decrease in the value of the equilibrium constant (K(c)) for the sorption of Cr(VI) ion.

  7. Population differentiation of southern Indian male lineages correlates with agricultural expansions predating the caste system.

    Science.gov (United States)

    Arunkumar, Ganeshprasad; Soria-Hernanz, David F; Kavitha, Valampuri John; Arun, Varatharajan Santhakumari; Syama, Adhikarla; Ashokan, Kumaran Samy; Gandhirajan, Kavandanpatti Thangaraj; Vijayakumar, Koothapuli; Narayanan, Muthuswamy; Jayalakshmi, Mariakuttikan; Ziegle, Janet S; Royyuru, Ajay K; Parida, Laxmi; Wells, R Spencer; Renfrew, Colin; Schurr, Theodore G; Smith, Chris Tyler; Platt, Daniel E; Pitchappan, Ramasamy

    2012-01-01

    Previous studies that pooled Indian populations from a wide variety of geographical locations, have obtained contradictory conclusions about the processes of the establishment of the Varna caste system and its genetic impact on the origins and demographic histories of Indian populations. To further investigate these questions we took advantage that both Y chromosome and caste designation are paternally inherited, and genotyped 1,680 Y chromosomes representing 12 tribal and 19 non-tribal (caste) endogamous populations from the predominantly Dravidian-speaking Tamil Nadu state in the southernmost part of India. Tribes and castes were both characterized by an overwhelming proportion of putatively Indian autochthonous Y-chromosomal haplogroups (H-M69, F-M89, R1a1-M17, L1-M27, R2-M124, and C5-M356; 81% combined) with a shared genetic heritage dating back to the late Pleistocene (10-30 Kya), suggesting that more recent Holocene migrations from western Eurasia contributed caste) system from the historically-documented Brahmin migrations into the area. In contrast, the overall Y-chromosomal patterns, the time depth of population diversifications and the period of differentiation were best explained by the emergence of agricultural technology in South Asia. These results highlight the utility of detailed local genetic studies within India, without prior assumptions about the importance of Varna rank status for population grouping, to obtain new insights into the relative influences of past demographic events for the population structure of the whole of modern India.

  8. A Reporting System to Protect the Human Rights of People Living with HIV and Key Populations.

    Science.gov (United States)

    Williamson, R Taylor; Fiscian, Vivian; Olson, Ryan Ubuntu; Poku, Fred Nana; Whittal, Joseph

    2017-12-01

    People living with HIV and key populations face human rights violations that affect their access to health services, relationships in their communities, housing options, and employment. To address these violations, government and civil society organizations in Ghana developed a discrimination reporting system managed by the Commission on Human Rights and Administrative Justice that links people living with HIV and key populations to legal services. This article presents findings on how Ghanaian stakeholders built this reporting system and discusses preliminary data on its impact. To organize our analysis, we used a conceptual framework that outlines the legal frameworks that protect human rights, the institutions that promote access to justice, and the mechanisms that link people living with HIV and key populations to legal services. Using in-depth interviews, we show that targeted technical assistance increased stakeholders' knowledge of issues that affect people living with HIV and key populations, strengthened these stakeholders' commitment to address discrimination, streamlined case management systems, and improved relationships between civil society and the government. Through case review, we find that most discrimination happens when accessing government services, inside communities and families, and in the workplace. Finally, we describe implications for other human rights commissions that are considering using a reporting system to protect human rights, including using legal frameworks, developing case management systems, and working with civil society.

  9. 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)

  10. 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)

  11. 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...

  12. Enzymatic U(VI) reduction by Desulfosporosinus species

    International Nuclear Information System (INIS)

    Suzuki, Y.; Kelly, S.D.; Kemner, K.M.; Banfield, J.F.

    2004-01-01

    Here we tested U(VI) reduction by a Desulfosporosinus species (sp.) isolate and type strain (DSM 765) in cell suspensions (pH 7) containing 1 mM U(VI) and lactate, under an atmosphere containing N 2 -CO 2 -H 2 (90: 5: 5). Although neither Desulfosporosinus species (spp.) reduced U(VI) in cell suspensions with 0.25% Na-bicarbonate or 0.85% NaCl, U(VI) was reduced in these solutions by a control strain, desulfovibrio desulfuricans (ATCC 642). However, both Desulfosporosinus strains reduced U(VI) in cell suspensions depleted in bicarbonate and NaCl. No U(VI) reduction was observed without lactate and H 2 electron donors or with heat-killed cells, indicating enzymatic U(VI) reduction. Uranium(VI) reduction by both strains was inhibited when 1 mM CuCl 2 was added to the cell suspensions. Because the Desulfosporosinus DSM 765 does not contain cytochrome c 3 used by Desulfovibrio spp. to reduce U(VI), Desulfosporosinus species reduce uranium via a different enzymatic pathway. (orig.)

  13. 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.

  14. 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.

  15. Population genetic studies in the Balkans. II. DNA-STR-systems.

    Science.gov (United States)

    Huckenbeck, W; Scheil, H G; Schmidt, H D; Efremovska, L; Xirotiris, N

    2001-09-01

    Within a study of the genetics of Southeastern European populations four DNA-STR-systems (D21S11, FGA, TH01, VWA) were examined in seven samples (samples of three Aromuns and four other Balkan populations). The results have been compared to data from four samples from literature (Austrians, Germans, Hungarians, Slovenians). The results show three clusters: a) the Aromuns from Albania (Andon Poci) and Macedonia (Stip region), b) the Romanian Aromuns (Kogalniceanu), Romanians (Constanta, Ploiesti) and Albanians (Tirana) und c) the data from literature. A sample of Northeastern Greece clearly differs from these three clusters. Including seven serum protein polymorphisms (without the populations from literature) results in two clusters: a) the three Aromun populations and b) Albanians and Romanians. Again the sample of Northeastern Greece clearly differs from these clusters.

  16. The association between systemic inflammatory cellular levels and lung function: a population-based study.

    Directory of Open Access Journals (Sweden)

    Tricia McKeever

    Full Text Available BACKGROUND: Lower lung function is associated with an elevated systemic white cell count in men. However, these observations have not been demonstrated in a representative population that includes females and may be susceptible to confounding by recent airway infections or recent cigarette smoking. We tested the hypothesis that lung function is inversely associated with systemic white cell count in a population-based study. METHODS: The study population consisted adults aged 17-90+ years who participated in the Third National Health and Nutrition Examination Survey who did not report a recent cough, cold or acute illness in a non-smoking and smoking population. RESULTS: In non-smoking adults with the highest quintile of the total white cell count had a FEV(1 125.3 ml lower than those in the lowest quintile (95% confidence interval CI: -163.1 to -87.5. Adults with the highest quintile of the total white cell count had a FVC 151.1 ml lower than those in the lowest quintile (95% confidence interval CI: -195.0 to -107.2. Similar associations were observed for granulocytes, mononuclear cells and lymphocytes. In current smokers, similar smaller associations observed for total white cell count, granulocytes and mononuclear cells. CONCLUSIONS: Systemic cellular inflammation levels are inversely associated with lung function in a population of both non-smokers and smokers without acute illnesses. This may contribute to the increased mortality observed in individuals with a higher baseline white cell count.

  17. Characterization of coherent population-trapped states in a circuit-QED Λ system

    Science.gov (United States)

    Premaratne, Shavindra P.; Wellstood, F. C.; Palmer, B. S.

    2017-10-01

    We examine coherent population trapping in a circuit-QED system consisting of an Al/AlOx/Al transmon qubit embedded in an Al three-dimensional cavity. By engineering the dissipation rate of the cavity to be much larger than that of the qubit and continuously pumping a two-photon process to an excited state of the cavity-qubit system, we are able to invert the population into the qubit excited state with a fidelity of 94%. Applying a second continuous drive tone at the dressed cavity frequency forms an effective Λ system and enables us to coherently trap the system in a dark state formed from a superposition of the excited and ground states of the qubit. By performing quantum state tomography we demonstrate that the position of the dark state on the Bloch sphere can be controlled by changing the relative amplitudes and phases of the two drives.

  18. Identificação da área de influência do serviço de atenção básica do sistema público de saúde à população idosa, município de Viçosa-MG Identification of the area of influence of the public basic health care delivery to the elderly population in Viçosa-MG

    Directory of Open Access Journals (Sweden)

    Ivonilce Venturi

    2008-08-01

    Full Text Available O objetivo deste estudo foi descrever as características demográficas e epidemiológicas da população idosa e identificar a área de influência dos serviços de atenção básica do sistema público de saúde em relação ao bairro de residência do idoso, identificar a taxa de utilização dos serviços e mapear a procura por atendimento de acordo com a localização geográfica da Unidade Básica de Saúde (UBS. Compuseram a amostra 6.964 atendimentos de saúde, prestados a 2.391 indivíduos idosos, ambos os sexos, que compareceram a um dos serviços públicos de atenção básica à saúde do município, no período de maio de 2003 a abril de 2004. Do total da amostra, 64,1% são do sexo feminino e 35,9%, do masculino. Os resultados mostram que as doenças cardiovasculares são as responsáveis pelo maior contingente de atendimentos no sistema de saúde. O número médio de consultas foi de 3,6 ao ano por idoso. O mapeamento geográfico permitiu visualizar que a procura por atendimento em determinadas UBS está relacionado com a especialidade médica que a unidade oferece e não com o local de residência do idoso. Os resultados deste estudo permitem identificar os bairros com maiores concentrações de enfermidades, como doenças cardiovasculares, indicando a necessidade da inserção de outros profissionais nas UBS dos bairros.This study aimed to describe the demographic and epidemiological characteristics of the elderly population, identify the area of influence of basic care in relation to the area of residence of the elderly and the rate of service use, as well as to map the demand according to the geographic location of the Basic Care Unit. The sample comprised 6,964 male and female subjects aged 60 years or more, who sought any of the outpatient public health services between May 2003 and April 2004. From this total, 64.1% were women and 35.9% men. The results show that cardiovascular diseases account for the greater part of

  19. Incidence and prevalence of systemic lupus erythematosus among the native Arab population in UAE.

    Science.gov (United States)

    Al Dhanhani, A M; Agarwal, M; Othman, Y S; Bakoush, O

    2017-05-01

    Background and objectives There is a paucity of information about the epidemiology of systemic lupus erythematosus (SLE) amongst Arabs. The objective of this study was to determine the incidence and prevalence of SLE among the native Arab population of United Arab Emirates (UAE). Methods Patients with SLE were identified from three sources: medical records of two local tertiary hospitals (four years; 2009 to 2012), laboratory requests for serum double stranded deoxyribonucleic acid and serum anti-nuclear antibody and confirmed histopathologic diagnosis of SLE (skin and kidney biopsy specimens). All the patients identified with SLE met the criteria of the American College of Rheumatology. Incidence and prevalence were calculated using the state records of the UAE native population as the denominator. The age-adjusted incidence was calculated by direct standardization using the World Health Organization world standard population 2000-2025. Results Sixteen new cases (13 females and three males) fulfilled the American College of Rheumatology SLE criteria. The mean (±SD) age at time of diagnosis was 28.6 ± 12.4 years. The crude incidence ratio (per 100,000 population) was 3.5, 1.1, 2.1 and 2.1 in years 2009, 2010, 2011, 2012, respectively. The age-standardized incidence per 100,000 population for the four years was 8.6 (95% confidence interval 4.2-15.9). The age-standardized prevalence of SLE among the native population according to the 2012 population consensus was 103/100,000 population (95% confidence interval 84.5-124.4). Conclusion The age-adjusted incidence and prevalence among UAE Arabs is higher than has been reported among most other Caucasian populations. Furthermore, the prevalence of SLE in UAE seems much higher than other similar Arab countries in the Gulf region.

  20. Mycorrhizal population on various cropping systems on sandy soil in dryland area of North Lombok, Indonesia

    Directory of Open Access Journals (Sweden)

    WAHYU ASTIKO

    2016-01-01

    Full Text Available Abstract. Astiko W, Fauzi MT, Sukartono. 2016. Mycorrhizal population on various cropping systems on sandy soil in dryland area of North Lombok, Indonesia. Nusantara Bioscience 8: 66-70. Inoculation of arbuscular mycorrhizal fungi (AMF on maize in sandy soil is expected to have positive implications for the improvement of AMF population and nutrient uptake. However, how many increases in the AMF population and nutrient uptake in the second cycle of a certain cropping system commonly cultivated by the farmers after growing their corn crop have not been examined. Since different cropping systems would indicate different increases in the populations of AMF and nutrient uptake. This study aimed to determine the population AMF and nutrient uptake on the second cropping cycle of corn-based cropping systems which utilized indigenous mycorrhizal fungi on sandy soil in dryland area of North Lombok, West Nusa Tenggara, Indonesia. For that purpose, an experiment was conducted at the Akar-Akar Village in Bayan Sub-district of North Lombok, designed according to the Randomized Complete Block Design, with four replications and six treatments of cropping cycles (P0 = corn-soybean as a control, in which the corn plants were not inoculated with AMF; P1 = corn-soybean, P2 = corn-peanut, P3 = corn-upland rice, P4 = corn-sorghum, and P5 = corn-corn, in which the first cycle corn plants were inoculated with AMF. The results indicated that the mycorrhizal populations (spore number and infection percentage were highest in the second cycle sorghum, achieving 335% and 226% respectively, which were significantly higher than those in the control. Increased uptake of N, P, K and Ca the sorghum plants at 60 DAS of the second cropping cycle reached 200%; 550%; 120% and 490% higher than in the control. The soil used in this experiment is rough-textured (sandy loam, so it is relatively low in water holding capacity and high porosity.

  1. Association of Systemic Lupus Erythematosus Clinical Features with European Population Genetic Substructure

    NARCIS (Netherlands)

    Alonso-Perez, Elisa; Suarez-Gestal, Marian; Calaza, Manuel; Witte, Torsten; Papasteriades, Chryssa; Marchini, Maurizio; Migliaresi, Sergio; Kovacs, Attila; Ordi-Ros, Josep; Bijl, Marc; Santos, Maria Jose; Ruzickova, Sarka; Pullmann, Rudolf; Carreira, Patricia; Skopouli, Fotini N.; D'Alfonso, Sandra; Sebastiani, Gian Domenico; Suarez, Ana; Blanco, Francisco J.; Gomez-Reino, Juan J.; Gonzalez, Antonio

    2011-01-01

    Systemic Lupus Erythematosus (SLE) is an autoimmune disease with a very varied spectrum of clinical manifestations that could be partly determined by genetic factors. We aimed to determine the relationship between prevalence of 11 clinical features and age of disease onset with European population

  2. Impacts of domestic population dynamics and foreign wood trade on deforestation: a world-system perspective.

    Science.gov (United States)

    Kick, E L; Burns, T J; Davis, B; Murray, D A; Murray, D A

    1996-06-01

    World system theory posits that core nations control global production processes through their economic and political-military strength, while countries at the periphery remain technologically underdeveloped and operate from a position of dependency. Rapid changes such as population growth and rural encroachment have spurred environmental degradation in the intermediary semi-periphery countries. The effects of world system structure on national deforestation were investigated in a quantitative, cross-national analysis of data from 60 core, semi-peripheral, and peripheral countries. This analysis revealed that rural population growth has had a deleterious effect on forestation throughout the world system. However, the impact of general population growth has been negative only in non-core countries. As hypothesized, forest exports have resulted in ecologic devastation in the periphery of the world system, but have exerted a favorable effect for core countries where reforestation programs dominate. These findings suggest that population growth per se is not the critical factor in environmental degradation. Urged are further quantitative evaluations of the environmental impact of other international commodity trades.

  3. Stimulus responsive hydrogel-coated etched fiber Bragg grating for carcinogenic chromium (VI) sensing

    Science.gov (United States)

    Kishore, Pabbisetti Vayu Nandana; Madhuvarasu, Sai Shankar; Moru, Satyanarayana

    2018-01-01

    This paper proposes a chemo-mechanical-optical sensing approach for the detection of carcinogenic chromium (VI) metal ion using an etched fiber Bragg grating (FBG) coated with stimulus responsive hydrogel. Hydrogel synthesized from the blends of (3-acrylamidopropyl)-trimethylammonium chloride, which is highly responsive to chromium ions suffers a volume change when placed in Cr solution. When the proposed sensor system is exposed to various concentrations of Cr (VI) ion solution, FBG peak shifts due to the mechanical strain induced by the swelling of the hydrogel. The peak shift is correlated with the concentration of the Cr (VI) metal ion. Due to the reduction in the cladding diameter of FBG, wastage of swelling force due to hydrogel on FBG is lowered and utilized for more wavelength peak shift of FBG resulting in the increase in the sensitivity. The resolution of the sensor system is found to be 0.072 ppb. Trace amounts of chromium (VI) ion as low as 10 ppb can be sensed by this method. The sensor has shown good sensitivity, selectivity, and repeatability. The salient features of the sensors are its compact size, light weight, and adoptability for remote monitoring.

  4. Adsorption and coadsorption mechanisms of Cr(VI) and organic contaminants on H3PO4 treated biochar.

    Science.gov (United States)

    Zhao, Nan; Zhao, Chuanfang; Lv, Yizhong; Zhang, Weifang; Du, Yuguo; Hao, Zhengping; Zhang, Jing

    2017-11-01

    The study of simultaneous removal of heavy metals and organic contaminants has practical applications due to the coexistence of complex pollutants in the wastewater or soil. In this work, biochar was prepared to study the removal efficiencies of Cr(VI), naphthalene (NAP) and bisphenol A (BPA) in the single or mixed systems. H 3 PO 4 -treated biochar presented a much higher adsorption capacity of the pollutants than the untreated biochar and also showed a high resistance to coexisting salts. The maximum adsorption capacities for Cr(VI) and BPA were 116.28 mg g -1 and 476.19 mg g -1 , respectively. Coadsorption experiments revealed that the presence of organic pollutants caused a limited decrease (∼10%) of removal efficiency of Cr(VI) and no further decrease was observed with higher concentrations of organic pollutants, while the presence of Cr(VI) had little impact on the removal of NAP. Infrared spectra and molecular simulation demonstrated that Cr(VI) was mainly adsorbed on the biochar via chemical complexation, while the organic pollutants through π-π interaction. Unexpectedly, the addition of Cr(VI) increased the removal efficiency of BPA, probably due to the increased H-bond interactions between BPA and the biochar through bridge bonds of oxygenic groups from CrO 4 2- . Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Solubility and sorption characteristics of uranium(VI) associated with rock samples and brines/groundwaters from WIPP and NTS

    International Nuclear Information System (INIS)

    Dosch, R.G.

    1981-01-01

    Solubility measurements for U(VI) in WIPP-related brines/groundwaters were made using initial U(VI) concentrations in the range of 1 to 50 μg/ml. Distribution coefficients (Kd) for U(VI) were determined for Culebra and Magenta dolomites using four different brine/groundwater compositions and for argillaceous shale and hornfels samples from the Eleana and Calico Hills Formation on NTS using a groundwater simulant typical of that area. The Kd's were evaluated as functions of: (1) U(VI) concentration (1.4 x 10 -4 to 1.4 μg/ml); (2) solution volume-to-rock mass ratios used in the measurements (5 to 100 ml/g), and for WIPP material only; (3) water composition (0 to 100% brine in groundwater); and (4) sample location in the Culebra and Magenta dolomite members of the Rustler Formation. The results indicate that if groundwater intrudes into a repository and leaches a waste form, significant concentrations of dissolved or colloidal U(VI) could be maintained in the liquid phase. Should these solutions enter an aquifer system, there are reasonable sets of conditions which could lead to subsequent migration of U(VI) away from the repository site

  6. Sensitive and selective electrochemical detection of chromium(VI) based on gold nanoparticle-decorated titania nanotube arrays.

    Science.gov (United States)

    Jin, Wei; Wu, Guosheng; Chen, Aicheng

    2014-01-07

    Owing to the severe toxicity and mobility of Cr(VI) in biological and environmental systems, it is of great importance to develop convenient and reliable methods for its detection. Here we report on a facile and effective electrochemical technique for monitoring Cr(VI) concentrations based on the utilization of Au nanoparticle-decorated titania nanotubes (TiO2NTs) grown on a titanium substrate. It was found that the electrochemical reduction of Cr(VI) at the Ti/TiO2NT/Au electrode exhibited an almost 23 fold improvement in activity as compared to a polycrystalline gold electrode, due to its nanoparticle/nanotubular heterojunction infrastructure. As a result, the Ti/TiO2NT/Au electrode demonstrated a wide linear concentration range from 0.10 μM to 105 μM, a low detection limit of 0.03 μM, and a high sensitivity of 6.91 μA μM(-1) Cr(VI) via amperometry, satisfying the detection requirements of the World Health Organization (WHO). Moreover, the Ti/TiO2NT/Au electrode exhibited good resistance against interference from coexisting Cr(III) and other metal ions, and excellent recovery for Cr(VI) detection in both tap and lake water samples. These attributes suggest that this hybrid sensor has strong potential in applications for the selective detection of Cr(VI).

  7. Stripping study of U(VI) from loaded TBP/n-paraffin using ammonium nitrate bearing waste as strippant

    International Nuclear Information System (INIS)

    Shrishma Paik; Biswas, S.; Bhattacharya, S.; Roy, S.B.

    2013-01-01

    Stripping studies of U(VI) from loaded solvent TBP/n-paraffin was carried out using ammonium nitrate solution as strippant. Effects of various stripping parameters such as concentration of ammonium nitrate solution, U(VI) concentration in organic phase, initial pH of strippant, temperature etc. have been investigated in detail. Kinetics of the stripping process by ammonium nitrate was found to be slower than that of stripping with water. It was observed that with the increase in ammonium nitrate concentration in aqueous solution, stripping of U(VI) decreased. With the increase in U(VI) loading in the organic phase, there was an increase in uranium stripping for ammonium nitrate whereas for distilled water it becomes reverse. With the increase in pH of the aqueous ammonium nitrate solution, stripping increased up to a certain pH of 8.5 and after that precipitation of uranium started. Increase in temperature of the biphasic system shows an enhancing effect of U(VI) stripping. Evaluation of thermodynamic data such as ΔH indicated that the process is endothermic. Based on the optimized conditions, McCabe-Thiele diagram was constructed for U(VI) stripping using ammonium nitrate solution at room temperature. (author)

  8. Pu(VI) nitrate crystallization behavior confirmation experiment

    International Nuclear Information System (INIS)

    Yano, Hajime; Nishimura, Kenji; Chikazawa, Takahiro; Teramae, Naoki

    2001-03-01

    Crystallization procedure is considered to have an advantage in recovering rather pure uranium from contaminated uranium solution and to be applicable for a new reprocessing process. It is considered necessary to collect data for Pu crystallization for design of the process with crystallization procedure. Last year the test for Pu(IV) nitrate crystallization was performed and it was confirmed that Pu crystallization is not observed under supposed crystallization condition if Pu valence is adjusted to 4. In this study, two type beaker tests were performed, 1. Pu(VI) nitrate crystallization test to confirm a behavior of Pu(VI) nitrate under crystallization condition. 2. U-Pu(VI) nitrate crystallization test to confirm a U-Pu(VI) co-crystallization phenomena. These tests were performed in AEA Technology Harwell Laboratory and the results were examined by Mitsubishi Materials Corporation. Test results were as follows. (1) Pu(VI) crystallization test. 1. Pu(VI) nitrate solution of 200,100 and 50 gPu/L with HNO 3 6M were cooled down up to -60degC to confirm Pu(VI) nitrate crystallization or freezing of the solution. 2. Crystal of H 2 O and HNO 3 · 3 H 2 O were observed but Pu(VI) nitrate crystallization was not observed. 3. We can estimate that Pu(VI) nitrate crystallization will not occurred in the reprocessing process with crystallization procedure. (2) U-Pu(VI) nitrate crystallization test. 1. U-Pu(VI) mixed nitrate solution is cooled to 10degC and 0degC. 2. U-Pu(VI) co-crystallization was confirmed by orange colored crystal in both cooling temperatures. 3. It is considered that Pu(VI) nitrate crystal is co-crystallized with uranyl nitrate crystal by the following reasons. chemical formula of both crystal are similar. crystal form is same and lattice parameters are very near. 4. U+Pu(VI) crystallization data is very near with uranyl nitrate crystallization data if Pu(VI) nitrate is considered to be crystallized in a same manner as uranyl nitrate. (author)

  9. 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.

  10. Population genetic structure in a social landscape: barley in a traditional Ethiopian agricultural system.

    Science.gov (United States)

    Samberg, Leah H; Fishman, Lila; Allendorf, Fred W

    2013-12-01

    Conservation strategies are increasingly driven by our understanding of the processes and patterns of gene flow across complex landscapes. The expansion of population genetic approaches into traditional agricultural systems requires understanding how social factors contribute to that landscape, and thus to gene flow. This study incorporates extensive farmer interviews and population genetic analysis of barley landraces (Hordeum vulgare) to build a holistic picture of farmer-mediated geneflow in an ancient, traditional agricultural system in the highlands of Ethiopia. We analyze barley samples at 14 microsatellite loci across sites at varying elevations and locations across a contiguous mountain range, and across farmer-identified barley types and management strategies. Genetic structure is analyzed using population-based and individual-based methods, including measures of population differentiation and genetic distance, multivariate Principal Coordinate Analysis, and Bayesian assignment tests. Phenotypic analysis links genetic patterns to traits identified by farmers. We find that differential farmer management strategies lead to markedly different patterns of population structure across elevation classes and barley types. The extent to which farmer seed management appears as a stronger determinant of spatial structure than the physical landscape highlights the need for incorporation of social, landscape, and genetic data for the design of conservation strategies in human-influenced landscapes.

  11. Horizontal Gene Transfer of Functional Type VI Killing Genes by Natural Transformation

    Directory of Open Access Journals (Sweden)

    Jacob Thomas

    2017-07-01

    Full Text Available Horizontal gene transfer (HGT can have profound effects on bacterial evolution by allowing individuals to rapidly acquire adaptive traits that shape their strategies for competition. One strategy for intermicrobial antagonism often used by Proteobacteria is the genetically encoded contact-dependent type VI secretion system (T6SS, a weapon used to kill heteroclonal neighbors by direct injection of toxic effectors. Here, we experimentally demonstrate that Vibrio cholerae can acquire new T6SS effector genes via horizontal transfer and utilize them to kill neighboring cells. Replacement of one or more parental alleles with novel effectors allows the recombinant strain to dramatically outcompete its parent. Using spatially explicit modeling, we examine how this process could affect the ecology and evolution of surface-attached microbial populations. HGT of T6SS effector-immunity pairs is risky: transformation brings a cell into conflict with its former clone mates but can be adaptive when superior T6SS alleles are acquired. More generally, we find that these costs and benefits are not symmetric and that high rates of HGT can act as a hedge against competitors with unpredictable T6SS efficacy. We conclude that antagonism and horizontal transfer drive successive rounds of weapon optimization and selective sweeps, dynamically shaping the composition of microbial communities.

  12. A multidrug resistance plasmid contains the molecular switch for type VI secretion in Acinetobacter baumannii

    Science.gov (United States)

    Weber, Brent S.; Ly, Pek Man; Irwin, Joshua N.; Pukatzki, Stefan; Feldman, Mario F.

    2015-01-01

    Infections with Acinetobacter baumannii, one of the most troublesome and least studied multidrug-resistant superbugs, are increasing at alarming rates. A. baumannii encodes a type VI secretion system (T6SS), an antibacterial apparatus of Gram-negative bacteria used to kill competitors. Expression of the T6SS varies among different strains of A. baumannii, for which the regulatory mechanisms are unknown. Here, we show that several multidrug-resistant strains of A. baumannii harbor a large, self-transmissible resistance plasmid that carries the negative regulators for T6SS. T6SS activity is silenced in plasmid-containing, antibiotic-resistant cells, while part of the population undergoes frequent plasmid loss and activation of the T6SS. This activation results in T6SS-mediated killing of competing bacteria but renders A. baumannii susceptible to antibiotics. Our data show that a plasmid that has evolved to harbor antibiotic resistance genes plays a role in the differentiation of cells specialized in the elimination of competing bacteria. PMID:26170289

  13. Geography, plants, and growing systems shape the genetic structure of Tunisian Botrytis cinerea populations.

    Science.gov (United States)

    Karchani-Balma, S; Gautier, A; Raies, A; Fournier, E

    2008-12-01

    Botrytis cinerea, considered for a long time as a generalist fungal pathogen of a multitude of plants, was recently shown to exhibit significant population structure in France according to the host, suggesting sympatric specialization. Recent models also showed that adaptation to new hosts may facilitate the process of sympatric speciation in fungal plant pathogens. The present work aimed at investigating if host plants, combined with geographic origin and growing systems, shape the diversity and structure of Tunisian populations of B. cinerea. We genotyped 153 isolates with 9 microsatellites. In all the investigated populations, the fungus reproduced mainly sexually. Gene flow was significantly reduced between greenhouses and open fields from strawberry but not from grapevine. Populations from tomatoes, sampled under greenhouses only, exhibited a low genotypic diversity. The effects of plant and geography from open fields were investigated on a sample of 74 isolates. Six populations were inferred, mainly structured according to a geographic barrier corresponding to the Grande Dorsale Mountain. However, this effect could not be separated from the host plant origin of isolates. The analysis of 63 isolates recovered from strawberries and faba beans in the Cap Bon and Centre regions did not reveal any significant effect of plant on pathogen population differentiation.

  14. FIA versatile system for spectrophotometric determinations of vanadium and molybdenum exploring the catalytic activities of V(V) and Mo(VI); Sistema FIA polivalente para determinacoes espectrofotometricas de vanadio e molibdenio explorando as atividades cataliticas de V(V) e Mo(VI)

    Energy Technology Data Exchange (ETDEWEB)

    Luca, Gilmara Caseri de

    1996-02-01

    A versatile system for chemical analysis by flow injection analysis was developed and applied for catalytic spectrophotometric determination of vanadium or molybdenum in metallic alloys. The selected methods were based upon indicator reactions chromotropic (CS)-bromate acid or hydrogen iodide-peroxide, respectively. Initially, a model system was proposed, in which common parameters for methods were studied. This included a re-sampling process in which high degrees of samples dilution were obtained. Other parameters such as concentrations and reagents addition order, reaction medium Ph, temperature and ionic power, as well as procedures for sample solubilization, were studied relating to each method. A mini-column with cationic exchanger resin (Dowex 50W-X8, 50-100 mesh, H{sup +} form) was used. The system for vanadium determination processes 120 samples by hour, consuming 2,0 mg CS and 10 mg K Br O{sub 3b}y determination. Concerning the method for molybdenum, the reagents consumption was 2,0 mg KI and 1,0 {mu}L of solution 30% H{sub 2}O{sub 2} by determination, since the analytic velocity was the same, in relation to vanadium.

  15. Utilizing population variation, vaccination, and systems biology to study human immunology

    Science.gov (United States)

    Tsang, John S.

    2016-01-01

    The move toward precision medicine has highlighted the importance of understanding biological variability within and across individuals in the human population. In particular, given the prevalent involvement of the immune system in diverse pathologies, an important question is how much and what information about the state of the immune system is required to enable accurate prediction of future health and response to medical interventions. Towards addressing this question, recent studies using vaccination as a model perturbation and systems-biology approaches are beginning to provide a glimpse of how natural population variation together with multiplexed, high-throughput measurement and computational analysis can be used to uncover predictors of immune response quality in humans. Here I discuss recent developments in this emerging field, with emphasis on baseline correlates of vaccination responses, sources of immune-state variability, as well as relevant features of study design, data generation, and computational analysis. PMID:26187853

  16. Utilizing population variation, vaccination, and systems biology to study human immunology.

    Science.gov (United States)

    Tsang, John S

    2015-08-01

    The move toward precision medicine has highlighted the importance of understanding biological variability within and across individuals in the human population. In particular, given the prevalent involvement of the immune system in diverse pathologies, an important question is how much and what information about the state of the immune system is required to enable accurate prediction of future health and response to medical interventions. Towards addressing this question, recent studies using vaccination as a model perturbation and systems-biology approaches are beginning to provide a glimpse of how natural population variation together with multiplexed, high-throughput measurement and computational analysis can be used to uncover predictors of immune response quality in humans. Here I discuss recent developments in this emerging field, with emphasis on baseline correlates of vaccination responses, sources of immune-state variability, as well as relevant features of study design, data generation, and computational analysis. Copyright © 2015 The Author. Published by Elsevier Ltd.. All rights reserved.

  17. Client-server, distributed database strategies in a healthcare record system for a homeless population.

    Science.gov (United States)

    Chueh, H C; Barnett, G O

    1993-01-01

    A computer-based healthcare record system being developed for Boston's Healthcare for the Homeless Program (BHCHP) uses client-server and distributed database technologies to enhance the delivery of healthcare to patients of this unusual population. The needs of physicians, nurses and social workers are specifically addressed in the application interface so that an integrated approach to healthcare for this population can be facilitated. These patients and their providers have unique medical information needs that are supported by both database and applications technology. To integrate the information capabilities with the actual practice of providers of care to the homeless, this computer-based record system is designed for remote and portable use over regular phone lines. An initial standalone system is being used at one major BHCHP site of care. This project describes methods for creating a secure, accessible, and scalable computer-based medical record using client-server, distributed database design.

  18. Dynamic Mechanism of Population Transfer and its Effect on Food Industries Credit Systems

    Directory of Open Access Journals (Sweden)

    Zhang Yanli

    2016-12-01

    Full Text Available Population transfer is a complicated social phenomenon which concerns the development of national welfare and people's livelihood and the credit system of the food production and processing industry. This study investigated the dynamic mechanism of population transfer and its effect on the food processing industry, applying theories like urbanization theory, regional imbalanced development theory, regional balanced development theory, comprehensive and coordinated development of urban and rural areas theory. Based on the practical situation of Henan province, the study offered some countermeasure suggestions for the existing problems in the credit systems of the food industry in Henan and discussed how to establish appropriate credit systems, thus to help food security and sustainable development of Henan.

  19. TWO-DIMENSIONAL LOCALIZATION OF ATOMIC POPULATIONS IN FOUR-LEVEL QUANTUM SYSTEMS

    Directory of Open Access Journals (Sweden)

    E. A. Efremova

    2014-07-01

    Full Text Available The paper deals with investigation of one aspect of fundamental problem of laser radiation interaction with the matter. This problem is spatial localization of atomic populations due to fields impact of few running waves. We are the first to propose in our work two–dimensional spatial localization of atomic populations in medium with tripod–like configuration of levels under the field influence of running waves only. Three running waves, propagating along one plane 120o angle-wise to each other, form the system of standing waves in this plane. Atomic populations can be localized in the field of these standing waves. Moreover, the degree of such localization can make up hundredth parts of the wavelength of the incident optical radiation. It is shown that an excitation of the central transition of the tripod-like system using a field of multidirectional linearly polarized running waves is the necessary condition of the population dependence from spatial coordinates in the XY – plane. The two–dimensional shapes that appear in this system can have very complicated structure such as “double – craters”.

  20. Sexual systems and population genetic structure in an annual plant: testing the metapopulation model.

    Science.gov (United States)

    Obbard, Darren J; Harris, Stephen A; Pannell, John R

    2006-03-01

    The need for reproductive assurance during dispersal, along with the pressure of local mate competition, means that the importance of frequent or repeated colonization is implicit in the literature on sexual system evolution. However, there have been few empirical tests of the association between colonization history and sexual system in plants, and none within a single species. Here we use patterns of genetic diversity to provide such a test in the Mercurialis annua species complex, which spans the range of systems from self-compatible monoecy through androdioecy to dioecy. This variation has been hypothesized to result from differing patterns of metapopulation turnover and recolonization. Because monoecy should be favored during colonization, androdioecy and dioecy will be maintained only in regions with low rates of local extinction and recolonization, and these differences should also be reflected in patterns of neutral genetic diversity. We show that monoecious populations of M. annua display lower within-population genetic diversity than androdioecious populations and higher genetic differentiation than dioecious and androdioecious populations, as predicted by metapopulation models. In contrast, regional diversity in M. annua appears to be primarily a product of postglacial range expansion from two refugia in the eastern and western Mediterranean Basin.

  1. A Cr(VI)-reducing Microbacterium sp. strain SUCR140 enhances growth and yield of Zea mays in Cr(VI) amended soil through reduced chromium toxicity and improves colonization of arbuscular mycorrhizal fungi.

    Science.gov (United States)

    Soni, Sumit K; Singh, Rakshapal; Awasthi, Ashutosh; Kalra, Alok

    2014-02-01

    Pot culture experiments were conducted in a glasshouse to evaluate the effects of four efficient Cr(VI)-reducing bacterial strains (SUCR44, SUCR140, SUCR186, and SUCR188) isolated from rhizospheric soil, and four arbuscular mycorrhizal fungi (AMF-Glomus mosseae, G. aggregatum, G. fasciculatum, and G. intraradices) alone or in combination, on Zea mays in artificially Cr(VI)-amended soil. Presence of a strain of Microbacterium sp. SUCR140 reduced the chromate toxicity resulting in improved growth and yields of plants compared to control. The bioavailability of Cr(VI) in soil and its uptake by the plant reduced significantly in SUCR140-treated plants; the effects of AMF, however, either alone or in presence of SUCR140 were not significant. On the other hand, presence of AMF significantly restricted the transport of chromium from root to the aerial parts of plants. The populations of AMF chlamydospores in soil and its root colonization improved in presence of SUCR140. This study demonstrates the usefulness of an efficient Cr(VI)-reducing bacterial strain SUCR140 in improving yields probably through reducing toxicity to plants by lowering bioavailability and uptake of Cr(VI) and improving nutrient availability through increased mycorrhizal colonization which also restricted the transport of chromium to the aerial parts.

  2. 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 ... mainly through consumption of food or water contami- nated with .... and healthy individuals (double arrows) followed by the detection using recombinant His-Vi protein as the primary antibody ...

  3. A CMOS rail-to-rail linear VI-converter

    NARCIS (Netherlands)

    Vervoort, P.P.; Vervoort, P.P.; Wassenaar, R.F.

    1995-01-01

    A linear CMOS VI-converter operating in strong inversion with a common-mode input range from the negative to the positive supply rail is presented. The circuit consists of three linear VI-converters based on the difference of squares principle. Two of these perform the actual V to I conversion,

  4. 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 ...

  5. 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) ...

  6. Adsorption kinetics for the removal of chromium (VI) from aqueous ...

    African Journals Online (AJOL)

    Adsorption kinetics for the removal of chromium (VI) from aqueous solutions on the activated carbons prepared from agricultural wastes. ... The batch removal of Cr(VI) from aqueous solution using low-cost adsorbents such as cornelian cherry, apricot stone and almond shell under different experimental conditions was ...

  7. Extraction of uranium (VI) sulphate complexes by Adogen amines

    International Nuclear Information System (INIS)

    Elyamani, I.S.; Abd Elmessieh, E.N.

    1995-01-01

    The distribution of U(VI) between aqueous H 2 So 4 solutions and organic phases of adogen-368 has been described. The dependence of extraction on acidity, diluent type, metal and extractant concentrations was investigated. The possible extraction mechanism is discussed in the light of results obtained. The separation of U(VI) from rare earths is suggested. 5 figs., 1 tab

  8. Spectroscopic characterization of iron-doped II-VI compounds for laser applications

    Science.gov (United States)

    Martinez, Alan

    The middle Infrared (mid-IR) region of the electromagnetic spectrum between 2 and 15 ?m has many features which are of interest to a variety of fields such as molecular spectroscopy, biomedical applications, industrial process control, oil prospecting, free-space communication and defense-related applications. Because of this, there is a demand for broadly tunable, laser sources operating over this spectral region which can be easily and inexpensively produced. II-VI semiconductor materials doped with transition metals (TM) such as Co 2+, Cr2+, or Fe2+ exhibit highly favorable spectroscopic characteristics for mid-IR laser applications. Among these TM dopants, Fe2+ has absorption and emission which extend the farthest into the longer wavelength portion of the mid-IR. Fe2+:II-VI crystals have been utilized as gain elements in laser systems broadly tunable over the 3-5.5 microm range [1] and as saturable absorbers to Q -switch [2] and mode-lock [3] laser cavities operating over the 2.7-3 microm. TM:II-VI laser gain elements can be fabricated inexpensively by means of post-growth thermal diffusion with large homogeneous dopant concentration and good optical quality[4,5]. The work outlined in this dissertation will focus on the spectroscopic characterization of TM-doped II-VI semiconductors. This work can be categorized into three major thrusts: 1) the development of novel laser materials, 2) improving and extending applications of TM:II-VI crystals as saturable absorbers, and 3) fabrication of laser active bulk crystals. Because current laser sources based on TM:II-VI materials do not cover the entire mid-IR spectral region, it is necessary to explore novel laser sources to extend available emissions toward longer wavelengths. The first objective of this dissertation is the spectroscopic characterization of novel ternary host crystals doped with Fe2+ ions. Using crystal field engineering, laser materials can be prepared with emissions placed in spectral regions not

  9. Optimizing magnetic nanoparticles for drinking water technology: The case of Cr(VI)

    Energy Technology Data Exchange (ETDEWEB)

    Simeonidis, K., E-mail: ksime@physics.auth.gr [Department of Mechanical Engineering, School of Engineering, University of Thessaly, Volos 38334 (Greece); Kaprara, E. [Department of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece); Samaras, T.; Angelakeris, M.; Pliatsikas, N.; Vourlias, G. [Department of Physics, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece); Mitrakas, M. [Department of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece); Andritsos, N. [Department of Mechanical Engineering, School of Engineering, University of Thessaly, Volos 38334 (Greece)

    2015-12-01

    The potential of magnetite nanoparticles to be applied in drinking water treatment for the removal of hexavalent chromium is discussed. In this study, a method for their preparation which combines the use of low-cost iron sources (FeSO{sub 4} and Fe{sub 2}(SO{sub 4}){sub 3}) and a continuous flow mode, was developed. The produced magnetite nanoparticles with a size of around 20 nm, appeared relatively stable to passivation providing a removal capacity of 1.8 μg Cr(VI)/mg for a residual concentration of 50 μg/L when tested in natural water at pH 7. Such efficiency is explained by the reducing ability of magnetite which turns Cr(VI) to an insoluble Cr(OH){sub 3} form. The successful operation of a small-scale system consisting of a contact reactor and a magnetic separator demonstrates a way for the practical introduction and recovery of magnetite nanoparticles in water treatment technology. - Highlights: • Iron sulfates were used for the kilogram scale production of Fe{sub 3}O{sub 4} nanoparticles. • Studied particles showed a Cr(VI) removal capacity of 2 μg/mg in natural water. • Cr(VI) uptake is mostly based on its reduction and precipitation as Cr(OH){sub 3}. • A continuous flow reactor–magnetic separator operated with nanoparticles.

  10. 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.

  11. Aminopyridine modified Spirulina platensis biomass for chromium(VI) adsorption in aqueous solution.

    Science.gov (United States)

    Bayramoglu, Gulay; Akbulut, Aydin; Arica, M Yakup

    Chemical modification of Spirulina platensis biomass was realized by sequential treatment of algal surface with epichlorohydrin and aminopyridine. Adsorptive properties of Cr(VI) ions on native and aminopyridine modified algal biomass were investigated by varying pH, contact time, ionic strength, initial Cr(VI) concentration, and temperature. FTIR and analytical analysis indicated that carboxyl and amino groups were the major functional groups for Cr(VI) ions adsorption. The optimum adsorption was observed at pH 3.0 for native and modified algal biomasses. The adsorption capacity was found to be 79.6 and 158.7 mg g(-1), for native and modified algal biomasses, respectively. For continuous system studies, the experiments were conducted to study the effect of important design parameters such as flow rate and initial concentration of metal ions, and the maximum sorption capacity was observed at a flow rate of 50 mL h(-1), and Cr(VI) ions concentration 200 mg L(-1) with modified biomass. Experimental data fitted a pseudo-second-order equation. The regeneration performance was observed to be 89.6% and 94.3% for native and modified algal biomass, respectively.

  12. An “on-off-on” fluorescent nanoprobe for recognition of chromium(VI) and ascorbic acid based on phosphorus/nitrogen dual-doped carbon quantum dot

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Xiaojuan, E-mail: gxj1124@sxu.edu.cn [Institute of Environmental Science, School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006 (China); Liu, Yang; Yang, Zhenhua; Shuang, Shaomin [Institute of Environmental Science, School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006 (China); Zhang, Zeyu [Faculty of Science, Beijing University of Chemical Technology, Beijing, 100029 (China); Dong, Chuan, E-mail: dc@sxu.edu.cn [Institute of Environmental Science, School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006 (China)

    2017-05-22

    Chromium (VI) [Cr(VI)] is a harsh environmental contaminates and has been proved to be highly toxic, carcinogenic and mutagenic. Therefore, developing an inexpensive, good selective and highly sensitive nanoprobe for the detection of Cr(VI) is in urgent demand. Recently, the highly fluorescent carbon quantum dots (CQDs) have been successfully utilized as efficient fluorescent nanoprobes for the detection of ions, pH and molecular substances. In this work, an “on-off” fluorescence phosphorus/nitrogen dual-doped CQDs (PNCQDs) probe was developed for the determination of Cr(VI) based on inner filter effect (IFE). The proposed PNCQDs nanoprobe shows its distinct merits of simplicity, convenience, fast implementation, good selectivity and high sensitivity towards Cr(VI), allowing its potential application in the determination of Cr(VI) in environment and biosystem. In addition, the chelation effect of the functional groups in reductant and Cr(VI), and the easy-conversion of Cr(VI) to reduced states (i.e. Cr(III) and Cr(0)) by reductants makes the minimization of IFE with a concomitant recovery of PNCQDs fluorescence possible. Hence, the PNCQDs/Cr(VI) hybrid was used as an “off-on” fluorescence probe for sensing ascorbic acid (AA), which is a model reductant. For the detection of Cr(VI), the linear range and the limit of detection achieved were 1.5–30 μmol/L and 23 nmol/L, respectively. For the detection of AA, the linear range and the limit of detection obtained were 5.0–200 μmol/L and 1.35 μmol/L, respectively. The as-constructed “on-off-on” PNCQDs fluorescent nanoprobe was successfully applied for detecting Cr(VI) and AA in biosystem. Furthermore, the as-constructed fluorescent sensing system was successfully applied to the analyses of AA in fresh fruits and in commercial fruit juices with satisfactory results. - Highlights: • Fast synthesis of phosphorus/nitrogen dual-doped CQDs (PNCQDs) by acid-base neutralization carbonization method.

  13. Removal of Cr(VI) onto Ficus carica biosorbent from water.

    Science.gov (United States)

    Gupta, V K; Pathania, Deepak; Agarwal, Shilpi; Sharma, Shikha

    2013-04-01

    The utilization of sustainable and biodegradable lignocellulosic fiber to detoxify the noxious Cr(VI) from wastewater is considered a versatile approach to clean up a contaminated aquatic environment. The aim of the present research is to assess the proficiency and mechanism of biosorption on Ficus carica bast fiber via isotherm models (Langmuir, Freundlich, Temkin, Harkin's-Jura, and Dubinin-Radushkevich), kinetic models, and thermodynamic parameters. The biomass extracted from fig plant was characterized by scanning electron microscopy and Fourier-transform infrared spectroscopy. To optimize the maximum removal efficiency, different parameters like effect of initial concentration, effect of temperature, pH, and contact time were studied by batch method. The equilibrium data were best represented by the Langmuir isotherm model, and the maximum adsorption capacity of Cr(VI) onto biosorbent was found to be 19.68 mg/g. The pseudo-second-order kinetic model adequately described the kinetic data. The calculated values of thermodynamic parameters such as enthalpy change (∆H(0)), entropy change (∆S(0)), and free energy change (∆G(0)) were 21.55 kJ/mol, 76.24 J/mol K, and -1.55 kJ/mol, respectively, at 30 °C which accounted for spontaneous and endothermic processes. The study of adsorbent capacity for Cr(VI) removal in the presence of Na(+), Mg(2+), Ca(2+), SO 4 (2-) , HCO 3 (-) and Cl(-) illustrated that the removal of Cr(VI) increased in the presence of HCO(3-) ions; the presence of Na(+), SO 4 (2-) or Cl(-) showed no significant influence on Cr(VI) adsorption, while Ca(2+) and Mg(2+) ions led to an insignificant decrease in Cr(VI) adsorption. Further, the desorption studies illustrated that 31.10% of metal ions can be removed from an aqueous system, out of which 26.63% of metal ions can be recovered by desorption in first cycle and the adsorbent can be reused. The results of the scale-up study show that the ecofriendly detoxification of Cr(VI) from aqueous

  14. 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.

  15. Hvad vi taler om, når vi taler om sømandskultur

    DEFF Research Database (Denmark)

    Gad, Christopher

    Hvad vi taler om, når vi taler om sømandskultur   As the anthropologist uses the notion of culture to control his field experiences, those experiences will, in turn, come to control his notion of culture. He invents “a culture” for people, and they invent “culture” for him (Wagner 1981:11) I følge...... et skib, som eksisterer i opposition til bl.a. en moderne højteknologisk udvikling. Filmen er en kultfilm i sømandskredse, og således har den dannet ramme for events med flere hundrede deltagere i Svendborg. Den kan da ses som et punkt, hvorudfra forestillinger om sømandsidentitet, køn, klasse...

  16. Human-induced changes in animal populations and distributions, and the subsequent effects on fluvial systems

    Science.gov (United States)

    Butler, David R.

    2006-09-01

    Humans have profoundly altered hydrological pathways and fluvial systems through their near-extirpation of native populations of animal species that strongly influenced hydrology and removal of surface sediment, and through the introduction of now-feral populations of animals that bring to bear a suite of different geomorphic effects on the fluvial system. In the category of effects of extirpation, examples are offered through an examination of the geomorphic effects and former spatial extent of beavers, bison, prairie dogs, and grizzly bears. Beavers entrapped hundreds of billions of cubic meters of sediment in North American stream systems prior to European contact. Individual bison wallows, that numbered in the range of 100 million wallows, each displaced up to 23 m 3 of sediment. Burrowing by prairie dogs displaced more than 5000 kg and possibly up to 67,500 kg of sediment per hectare. In the category of feral populations, the roles of feral rabbits, burros and horses, and pigs are highlighted. Much work remains to adequately quantify the geomorphic effects animals have on fluvial systems, but the influence is undeniable.

  17. A model of population dynamics of TB in a prison system and application to South Africa.

    Science.gov (United States)

    Witbooi, Peter; Vyambwera, Sibaliwe Maku

    2017-11-29

    Tuberculosis (TB) continues to spread in South African prisons in particular, as prisons are over-capacitated and have poor ventilation. The awaiting trial detainees are not screened on admission and are at high risk of getting infected with TB. We propose a compartmental model to describe the population dynamics of TB disease in prisons. Our model considers the inflow of susceptible, exposed and TB infectives into the prison population. Removal of individuals out of the prison population can be either by death or by being released from prison, as compared to a general population in which removal is only by death. We describe conditions, including non-inflow of infectives into the prison, which will ensure that TB can be eradicated from the prison population. The model is calibrated for the South African prison system, by using data in existing literature. The model can be used to make quantitative projections of TB prevalence and to measure the effect of interventions. Illustrative simulations in this regard are presented. The model can be used for other prison populations too, if data is available to calculate the model parameters. Various simulations generated with our model serve to illustrate how it can be utilized in making future projections of the levels of prevalence of TB, and to quantify the effect of interventions such as screening, treatment or reduction of transmission parameter values through improved living conditions for inmates. This makes it particularly useful as there are various targets set by the World Health Organization and by governments, for reduction of TB prevalence and ultimately its eradication. Towards eradication of TB from a prison system, the theorem on global stability of the disease-free state is a useful indicator.

  18. Population differentiation of southern Indian male lineages correlates with agricultural expansions predating the caste system.

    Directory of Open Access Journals (Sweden)

    Ganeshprasad Arunkumar

    Full Text Available Previous studies that pooled Indian populations from a wide variety of geographical locations, have obtained contradictory conclusions about the processes of the establishment of the Varna caste system and its genetic impact on the origins and demographic histories of Indian populations. To further investigate these questions we took advantage that both Y chromosome and caste designation are paternally inherited, and genotyped 1,680 Y chromosomes representing 12 tribal and 19 non-tribal (caste endogamous populations from the predominantly Dravidian-speaking Tamil Nadu state in the southernmost part of India. Tribes and castes were both characterized by an overwhelming proportion of putatively Indian autochthonous Y-chromosomal haplogroups (H-M69, F-M89, R1a1-M17, L1-M27, R2-M124, and C5-M356; 81% combined with a shared genetic heritage dating back to the late Pleistocene (10-30 Kya, suggesting that more recent Holocene migrations from western Eurasia contributed <20% of the male lineages. We found strong evidence for genetic structure, associated primarily with the current mode of subsistence. Coalescence analysis suggested that the social stratification was established 4-6 Kya and there was little admixture during the last 3 Kya, implying a minimal genetic impact of the Varna (caste system from the historically-documented Brahmin migrations into the area. In contrast, the overall Y-chromosomal patterns, the time depth of population diversifications and the period of differentiation were best explained by the emergence of agricultural technology in South Asia. These results highlight the utility of detailed local genetic studies within India, without prior assumptions about the importance of Varna rank status for population grouping, to obtain new insights into the relative influences of past demographic events for the population structure of the whole of modern India.

  19. U(VI) sorption on granite: prediction and experiments

    International Nuclear Information System (INIS)

    Nebelung, C.; Brendler, V.

    2010-01-01

    One widely accepted approach - component additivity (CA) - to describe the sorption of contaminants onto complex materials such as rocks or soils is based on the assumption that the surface of a complex mineral assemblage is composed of a mixture of mineral constituents whose surface properties are known from independent studies. An internally consistent SCM (surface complexation model) database can be developed that describes the adsorption reactions of solutes to each phase. Here, the capability of such a methodology was tested, using the code MINTEQA2 including thermodynamic data of the NEA-TDB, and literature data for SCM, namely the DDL model. The sorption characteristics of U(VI) on granite (from Eibenstock, Saxony, Germany, with the main components quartz, albite, orthoclase, and muscovite) was predicted and then compared to batch experiments. Granite plays an important role in the remediation of former uranium ore mining and milling sites, but is also one of the host rocks considered for final disposal of nuclear materials. Safety assessment requires a detailed understanding of this system and its retention potential with regard to hazardous components. Namely the sorption of uranium in this complex rock is not fully understood yet. The experiments thus also provided a better understanding of the far-field behaviour in granitic geological nuclear repositories. The robustness of the prediction was tested by variation of the granite composition and the variation of the specific surface area (SSA) - first all components were predicted with a uniform granite SSA, second with a distinct SSA for each granite component (determined on pure minerals for the same grain size fractions). Changes in compositions yielded only marginal differences in the prediction. Different approaches to SSA showed somewhat larger deviations. In conclusion, the CA methodology is a valid and robust approach to U(VI) sorption onto complex substrates such as granite, provided sufficient

  20. Kinetic investigations of quinoline oxidation by ferrate(VI).

    Science.gov (United States)

    Luo, Zhiyong; Li, Xueming; Zhai, Jun

    2016-01-01

    Quinoline is considered as one of the most toxic and carcinogenic compounds and is commonly found in industrial wastewaters, which require treatment before being discharged. Removal of quinoline by the use of an environmentally friendly oxidant, potassium ferrate(VI) (K2FeO4), was assessed by studying the kinetics of the oxidation of quinoline by ferrate(VI) (Fe(VI)) as a function of pH (8.53-10.53) and temperature (21-36°C) in this work. The reaction of quinoline with Fe(VI) was found to be first order in Fe(VI), half order in quinoline, and 1.5 order overall. The observed rate constant at 28°C decreased non-linearly from 0.5334 to 0.2365 M(-0.5) min(-1) with an increase in pH from 8.53 to 10.03. Considering the equilibria of Fe(VI) and quinoline, the reaction between quinoline and Fe(VI) contained two parallel reactions under the given pH conditions. The individual rate constants of these two reactions were determined. The results indicate that the protonated species of Fe(VI) reacts more quickly with quinoline than the deprotonated form of Fe(VI). The reaction activation energy Ea was obtained to be 51.44 kJ·mol(-1), and it was slightly lower than that of conventional chemical reaction. It reveals that the oxidation of quinoline by Fe(VI) is feasible in the routine water treatment.

  1. Ten tips for treating acne vulgaris in Fitzpatrick skin types IV-VI.

    Science.gov (United States)

    Spann, Candace Thornton

    2011-06-01

    During the 21st century, people with skin of color will account for a large portion of the US population. According to race projections from the US Census Bureau, persons of African American, Hispanic, Asian and Native American descent will make up nearly half of the total US population by the year 2050. Because of our changing demographics, it is important that all dermatologists become comfortable in treating skin of color. This article provides 10 practical pearls for management of acne vulgaris in patients with Fitzpatrick skin types IV-VI.

  2. 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 phase-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.

  3. Quantifying Nearshore Sea Turtle Densities: Applications of Unmanned Aerial Systems for Population Assessments.

    Science.gov (United States)

    Sykora-Bodie, Seth T; Bezy, Vanessa; Johnston, David W; Newton, Everette; Lohmann, Kenneth J

    2017-12-18

    Although sea turtles face significant pressure from human activities, some populations are recovering due to conservation programs, bans on the trade of turtle products, and reductions in bycatch. While these trends are encouraging, the status of many populations remains unknown and scientific monitoring is needed to inform conservation and management decisions. To address these gaps, this study presents methods for using unmanned aerial systems (UAS) to conduct population assessments. Using a fixed-wing UAS and a modified strip-transect method, we conducted aerial surveys along a three-kilometer track line at Ostional, Costa Rica during a mass-nesting event of olive ridley turtles (Lepidochelys olivacea). We visually assessed images collected during six transects for sea turtle presence, resulting in 682 certain detections. A cumulative total of 1091 certain and probable turtles were detected in the collected imagery. Using these data, we calculate estimates of sea turtle density (km -2 ) in nearshore waters. After adjusting for both availability and perception biases, we developed a low-end estimate of 1299 ± 458 and a high-end estimate of 2086 ± 803 turtles per km -2 . This pilot study illustrates how UAS can be used to conduct robust, safe, and cost-effective population assessments of sea turtle populations in coastal marine ecosystems.

  4. Primary care utilisation patterns among an urban immigrant population in the Spanish National Health System

    Directory of Open Access Journals (Sweden)

    Bordonaba-Bosque Daniel

    2011-06-01

    Full Text Available Abstract Background There is evidence suggesting that the use of health services is lower among immigrants after adjusting for age and sex. This study takes a step forward to compare primary care (PC utilisation patterns between immigrants and the native population with regard to their morbidity burden. Methods This retrospective, observational study looked at 69,067 individuals representing the entire population assigned to three urban PC centres in the city of Zaragoza (Aragon, Spain. Poisson models were applied to determine the number of annual PC consultations per individual based on immigration status. All models were first adjusted for age and sex and then for age, sex and case mix (ACG System®. Results The age and sex adjusted mean number of total annual consultations was lower among the immigrant population (children: IRR = 0.79, p Conclusions Although immigrants make lower use of PC services than the native population after adjusting the consultation rate for age and sex, these differences decrease significantly when considering their morbidity burden. These results reinforce the 'healthy migration effect' and discount the existence of differences in PC utilisation patterns between the immigrant and native populations in Spain.

  5. Multiscale Problems in Circadian Systems Biology: From Gene to Cell to Performance

    Science.gov (United States)

    2012-03-22

    the gametogenetic cycles in tropical hermatypic corals to the appropriate spawning season since photosynthate is their primary source of energy...scale phenomena in many other biological systems including the annual spawning of certain species of corals and; (vi) derivation of rigorous...the application domains of ecology, with the broad technical theme of understanding synchronized population-scale phenomena, such as coral spawning

  6. The reduction of Np(VI) and Pu(VI) by organic chelating agents

    International Nuclear Information System (INIS)

    Reed, D.T.; Aase, S.B.; Banaszak, J.E.

    1998-01-01

    The reduction of NpO 2+ and PuO 2 2+ by oxalate. citrate, and ethylenediaminetetraacetic acid (EDTA) was investigated in low ionic strength media and brines. This was done to help establish the stability of the An(VI) oxidation state in the presence of organic complexants. The stability of the An(VI) oxidation state depended on the pH and relative strength of the various oxidation state-specific complexes. At low ionic strength and pH 6, NpO 2 O 2+ was rapidly reduced to form NpO 2 + organic complexes. At longer times, Np(IV) organic complexes were observed in the presence of citrate. PuO 2 2+ was predominantly reduced to Pu 4+ , resulting in the formation of organic complexes or polymeric/hydrolytic precipitates. The relative rates of reduction to the An(V) complex were EDTA > citrate > oxalate. Subsequent reduction to An(IV) complexes, however, occurred in the following order: citrate > EDTA > oxalate because of the stability of the An(V)-EDTA complex. The presence of organic complexants led to the rapid reduction of NpO 2 2+ and PuO 2 P 2+ in G-seep brine at pHs 5 and 7. At pHs 8 and 10 in ERDA-6 brine, carbonate and hydrolytic complexes predominated and slowed down or prevented the reduction of An(VI) by the organics present

  7. World Workshop on Oral Medicine VI

    DEFF Research Database (Denmark)

    Villa, Alessandro; Wolff, Andy; Aframian, Doron

    2015-01-01

    were retained for further analysis. RESULTS: There were limited data on the epidemiology of MISGD. Furthermore, various methods were used to assess salivary flow rate or xerostomia. Preventive and therapeutic strategies included substitution of medications, oral, or systemic therapy with sialogogues...... with xerostomia and salivary gland dysfunction through a thorough medical history. Preferably, health care providers should measure the unstimulated and stimulated whole salivary flow rates of all their patients so that these values can be used as a baseline to rate the complaints of patients who subsequently...... claim to experience xerostomia or salivary gland dysfunction as well as the possibilities of effectively treating this condition. CLINICAL RELEVANCE: MISGD remains a major burden for the population. This systematic review provides a contemporary in-depth description of the diagnosis and treatment...

  8. Stationary solutions to a system of size-structured populations with nonlinear growth rate.

    Science.gov (United States)

    Kato, Nobuyuki

    2012-01-01

    We study stationary solutions to a system of size-structured population models with nonlinear growth rate. Several characterizations of stationary solutions are provided. It is shown that the steady-state problem can be converted into different problems such as two types of eigenvalue problems and a fixed-point problem. In the two-species case, we give an existence result of nonzero stationary solutions by using the fixed-point problem.

  9. Feedback controlled dephasing and population relaxation in a two-level system

    International Nuclear Information System (INIS)

    Wang Jin

    2009-01-01

    This Letter presents the maximum achievable stability and purity that can be obtained in a two-level system with both dephasing and population relaxation processes by using homodyne-mediated feedback control. An analytic formula giving the optimal amplitudes of the driving and feedback for the steady-state is also presented. Experimental examples are used to show the importance of controlling the dephasing process.

  10. Designing for Underserved Populations: Constraints and Requirements of Personal Health Record Systems

    Centers for Disease Control (CDC) Podcasts

    2009-02-11

    In this podcast, Dr. Thomas Horan discusses how language, literacy, and access barriers can be overcome with electronic Personal Health Record (PHR) systems to improve health among the most vulnerable, isolated, and underserved populations.  Created: 2/11/2009 by Coordinating Center for Health Information Service (CCHIS), Healthy Healthcare Settings Goal Team, Office of Strategy and Innovation.   Date Released: 9/2/2009.

  11. Analysis of mating system in two Pinus cembra L. populations of the Ukrainian Carpathians

    Directory of Open Access Journals (Sweden)

    Dmitri V. Politov

    2013-12-01

    Full Text Available Volume 51 (1, 2008, pages 11-18Back Analysis of mating system in two Pinus cembra L. populations of the Ukrainian Carpathians     D.V. PolitovLaboratory of Population Genetics, Vavilov Institute of General Genetics, Russian Academy of Sciences Y.V. PirkoInstitute of Cell Biology and Genetic Engineering, Ukraine N.N. PirkoInstitute of Cell Biology and Genetic Engineering, Ukraine E.A. MudrikDonetsk Botanical Gardens, Ukraine I.I. KorshikovDonetsk Botanical Gardens, Ukraine  contact authors by Editorial Office  SUMMARY  In natural pine populations, a mixed mating system is typical, characterized by the proportions of selfed and outcrossed seeds. Swiss stone pine (Pinus cembra L. is one of the least studied European conifers in this respect. The mating system of six polymorphic allozyme loci were studied in haploid megagametophytes and diploid open-pollinated embryos in two stands located in the East Carpathians. In the 'Gorgany' population (24 trees, 198 seeds the mean singlelocus estimated outcrossing rate (ts was 0.731, and the multilocus estimate (tm was 0.773. In the 'Yayko' population the outcrossing rate was lower (27 trees, 213 seeds, ts=0.645, tm=0.700, suggesting 23-30% of seeds are self-pollinated. Correlation of outcrossing rate estimates among loci was less than 1, (0.300 in 'Gorgany' and 0.469 in 'Yayko' indicating biparental inbreeding occurred. Differences between tm and ts (0.042 in 'Gorgany' and 0.056 in 'Yayko' can also be influenced by consanguineous mating, indicated by the presence of spatial and genetic family structure. In small isolated populations of Pinus cembra, which are typical for the Carpathian part of the species' range, inbreeding depression may negatively affect seed quality. The high proportion of selfed seeds observed here can be expected in any seedlot of this species and should be taken into account while planning gene conservation or reforestation measures. Maternal trees in these populations

  12. Efficient Analysis of Systems Biology Markup Language Models of Cellular Populations Using Arrays.

    Science.gov (United States)

    Watanabe, Leandro; Myers, Chris J

    2016-08-19

    The Systems Biology Markup Language (SBML) has been widely used for modeling biological systems. Although SBML has been successful in representing a wide variety of biochemical models, the core standard lacks the structure for representing large complex regular systems in a standard way, such as whole-cell and cellular population models. These models require a large number of variables to represent certain aspects of these types of models, such as the chromosome in the whole-cell model and the many identical cell models in a cellular population. While SBML core is not designed to handle these types of models efficiently, the proposed SBML arrays package can represent such regular structures more easily. However, in order to take full advantage of the package, analysis needs to be aware of the arrays structure. When expanding the array constructs within a model, some of the advantages of using arrays are lost. This paper describes a more efficient way to simulate arrayed models. To illustrate the proposed method, this paper uses a population of repressilator and genetic toggle switch circuits as examples. Results show that there are memory benefits using this approach with a modest cost in runtime.

  13. Optimizing the application of magnetic nanoparticles in Cr(VI) removal

    Science.gov (United States)

    Simeonidis, Konstantinos; Kaprara, Efthymia; Mitrakas, Manassis; Tziomaki, Magdalini; Angelakeris, Mavroidis; Vourlias, Georgios; Andritsos, Nikolaos

    2013-04-01

    The presence of heavy metals in aqueous systems is an intense health and environmental problem as implied by their harmful effects on human and other life forms. Among them, chromium is considered as an acutely hazardous compound contaminating the surface water from industrial wastes or entering the groundwater, the major source of drinking water, by leaching of chromite rocks. Chromium occurs in two stable oxidation states, Cr(III) and Cr(VI), with the hexavalent form being much more soluble and mobile in water having the ability to enter easily into living tissues or cells and thus become more toxic. Despite the established risks from Cr(VI)-containing water consumption and the increasing number of incidents, the E.U. tolerance limit for total chromium in potable water still stands at 50 μg/L. However, in the last years a worldwide debate concerning the establishment of a separate and very strict limit for the hexavalent form takes place. In practice, Cr(VI) is usually removed from water by various methods such as chemical coagulation/filtration, ion exchange, reverse osmosis and adsorption. Adsorption is considered as the simplest method which may become very effective if the process is facilitated by the incorporation of a Cr(VI) to Cr(III) reduction stage. This work studies the potential of using magnetic nanoparticles as adsorbing agents for Cr(VI) removal at the concentration levels met in contaminated drinking water. A variety of nanoparticles consisting of ferrites MFe2O4 (M=Fe, Co, Ni, Cu, Mn, Mg, Zn) were prepared by precipitating the corresponding bivalent or trivalent sulfate salts under controlled acidity and temperature. Electron microscopy and X-ray diffraction techniques were used to verify their crystal structure and determine the morphological characteristics. The mean particle size of the samples was found in the range 10-50 nm. Batch Cr(VI) removal tests were performed in aqueous nanoparticles dispersions showing the efficiency of ferrite

  14. Modeling possible cooling-water intake system impacts on Ohio River fish populations.

    Science.gov (United States)

    Perry, Elgin; Seegert, Greg; Vondruska, Joe; Lohner, Timothy; Lewis, Randy

    2002-04-26

    To assess the possible impacts caused by cooling-water intake system entrainment and impingement losses, populations of six target fish species near power plants on the Ohio River were modeled. A Leslie matrix model was constructed to allow an evaluation of bluegill, freshwater drum, emerald shiner, gizzard shad, sauger, and white bass populations within five river pools. Site-specific information on fish abundance and length-frequency distribution was obtained from long-term Ohio River Ecological Research Program and Ohio River Sanitation Commission (ORSANCO) electrofishing monitoring programs. Entrainment and impingement data were obtained from 316(b) demonstrations previously completed at eight Ohio River power plants. The model was first run under a scenario representative of current conditions, which included fish losses due to entrainment and impingement. The model was then rerun with these losses added back into the populations, representative of what would happen if all entrainment and impingement losses were eliminated. The model was run to represent a 50-year time period, which is a typical life span for an Ohio River coal-fired power plant. Percent changes between populations modeled with and without entrainment and impingement losses in each pool were compared to the mean interannual coefficient of variation (CV), a measure of normal fish population variability. In 6 of the 22 scenarios of fish species and river pools that were evaluated (6 species x 5 river pools, minus 8 species/river pool combinations that could not be evaluated due to insufficient fish data), the projected fish population change was greater than the expected variability of the existing fish population, indicating a possible adverse environmental impact. Given the number of other variables affecting fish populations and the conservative modeling approach, which assumed 100% mortality for all entrained fish and eggs, it was concluded that the likelihood of impact was by no means

  15. Modeling Possible Cooling-Water Intake System Impacts on Ohio River Fish Populations

    Directory of Open Access Journals (Sweden)

    Elgin Perry

    2002-01-01

    Full Text Available To assess the possible impacts caused by cooling-water intake system entrainment and impingement losses, populations of six target fish species near power plants on the Ohio River were modeled. A Leslie matrix model was constructed to allow an evaluation of bluegill, freshwater drum, emerald shiner, gizzard shad, sauger, and white bass populations within five river pools. Site-specific information on fish abundance and length-frequency distribution was obtained from long-term Ohio River Ecological Research Program and Ohio River Sanitation Commission (ORSANCO electrofishing monitoring programs. Entrainment and impingement data were obtained from 316(b demonstrations previously completed at eight Ohio River power plants. The model was first run under a scenario representative of current conditions, which included fish losses due to entrainment and impingement. The model was then rerun with these losses added back into the populations, representative of what would happen if all entrainment and impingement losses were eliminated. The model was run to represent a 50-year time period, which is a typical life span for an Ohio River coal-fired power plant. Percent changes between populations modeled with and without entrainment and impingement losses in each pool were compared to the mean interannual coefficient of variation (CV, a measure of normal fish population variability. In 6 of the 22 scenarios of fish species and river pools that were evaluated (6 species × 5 river pools, minus 8 species/river pool combinations that could not be evaluated due to insufficient fish data, the projected fish population change was greater than the expected variability of the existing fish population, indicating a possible adverse environmental impact. Given the number of other variables affecting fish populations and the conservative modeling approach, which assumed 100% mortality for all entrained fish and eggs, it was concluded that the likelihood of impact was

  16. Genetic Diversity in Relict and Fragmented Populations of Ulmus glabra Hudson in the Central System of the Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    María Martín del Puerto

    2017-04-01

    Full Text Available Ulmus glabra Hudson, or Wych elm, occurs as fragmented and relict natural populations in the Central System, which acts as a refugium in the Iberian Peninsula. Considering the importance of the Central System populations of U. glabra, the main objective was to assess their genetic diversity using nuclear microsatellite markers. A total of 360 different genotypes were detected in the 427 U. glabra individuals analyzed. Wych elm populations showed a highly significant genetic differentiation (24%; p = 0.0001. Of the 22 populations studied, population of Rozas de Puerto Real (ROZ showed the highest values of effective number of alleles (2.803, mean Shannon’s diversity (1.047 and expected heterozygosity (0.590. Populations of ROZ and Mombeltrán (MOM showed the highest values of observed heterozygosity (0.838 and 0.709, respectively, and highly negative values for inbreeding coefficient (−0.412 and −0.575, respectively. Also, most of putative hybrids (50 of 55 were observed in these two populations. Demographic analysis revealed signals for recent (four populations and ancestral (fifteen populations bottlenecks. Fragmented populations with diminishing number of individuals, along with anthropogenic intervention and Dutch elm disease (DED, are the main threats to U. glabra populations. From a future perspective, the information generated can be considered in the formulation of conservation strategies for U. glabra populations in the Central System.

  17. Earthworm Population Density in Sugarcane Cropping System Applied with Various Quality of Organic Matter

    Directory of Open Access Journals (Sweden)

    Nurhidayati Nurhidayati

    2012-12-01

    Full Text Available Earthworms population in the soil are greatly impacted by agricultural management, yet little is known about how the quality and quantity of organic matter addition interact in sugarcane cropping system to earthworm population. This study describes the effect of various organic matter and application rates on earthworms in sugarcane cropping system. Earthworms were collected in April, July and December from 48 experimental plots under five kinds of organic matter application : (1 cattle manure, (2 filter cake of sugar mill, (3 sugarcane trash, (4 mixture of cattle manure+filter cake, and (5 mixture of cattle manure+sugarcane trash. There were three application rates of the organic matter (5, 10, and 15 ton ha-1. The treatments were arranged in factorial block randomize design with three replications and one treatment as a control (no organic input. Earthworms were collected using monolith sampling methods and hand-sorted from each plot, and measured its density (D (indiv.m-2, biomass (B (g m-2 and B/D ratio (g/indiv.. All the plots receiving organic matter input had higher earthworm density, biomass, and B/D ratio than the control. The highest earthworm population density was found in the plot receiving application of sugarcane trash (78 indiv.m-2 and the mixture of cattle manure+sugarcane trash (84 indiv.m-2. The increase in application rates of organic matter could increase the earthworm density and biomass. Earthworm population density also appeared to be strongly influenced by the quality of organic matter, such as the C-organic, N, C/N ratio, lignin, polyphenols, and cellulose content. Earthworm preferred low quality organic matter. It was caused by the higher energy of low quality organic matter than high quality organic matter. Our findings suggest that the input of low quality organic matter with application rate as 10 ton ha-1 is important for maintaining earthworm population and soil health in sugarcane land.

  18. Analysis of mating system in two Pinus cembra L. populations of the Ukrainian Carpathians

    Directory of Open Access Journals (Sweden)

    Dmitri V. Politov

    2008-09-01

    Full Text Available In natural pine populations, a mixed mating system is typical,characterized by the proportions of selfed and outcrossed seeds. Swiss stone pine(Pinus cembra L. is one of the least studied European conifers in this respect. The mating system of six polymorphic allozyme loci were studied in haploid megagametophytes and diploid open-pollinated embryos in two stands located in theEast Carpathians. In the 'Gorgany' population (24 trees, 198 seeds the mean singlelocus estimated outcrossing rate (ts was 0.731, and the multilocus estimate (tm was 0.773. In the 'Yayko' population the outcrossing rate was lower (27 trees, 213 seeds, ts=0.645, tm=0.700, suggesting 23-30% of seeds are self-pollinated. Correlation ofoutcrossing rate estimates among loci was less than 1, (0.300 in 'Gorgany' and 0.469 in 'Yayko' indicating biparental inbreeding occurred. Differences between tm and ts (0.042 in 'Gorgany' and 0.056 in 'Yayko' can also be influenced by consanguineous mating, indicated by the presence of spatial and genetic family structure. In small isolated populations of Pinus cembra, which are typical for the Carpathian part of the species' range, inbreeding depression may negatively affect seed quality. The high proportion of selfed seeds observed here can be expected in any seedlot of this species and should be taken into account while planning gene conservation orreforestation measures. Maternal trees in these populations showed no heterozygote deficiency at these allozyme loci, and instead showed increased proportions of heterozygotes (inbreeding coefficient FIS = -0.200 in 'Gorgany' and -0.142 in 'Yayko'. Balancing selection may explain heterozygosity levels up to and above equilibrium proportions.

  19. Designing and implementing a Quality Broker: the GeoViQua experience

    Science.gov (United States)

    Papeschi, Fabrizio; Bigagli, Lorenzo; Masò, Joan; Nativi, Stefano

    2014-05-01

    GeoViQua (QUAlity aware VIsualisation for the Global Earth Observation System of Systems) is an FP7 project aiming at complementing the Global Earth Observation System of Systems (GEOSS) with rigorous data quality specifications and quality-aware capabilities, in order to improve reliability in scientific studies and policy decision-making. GeoViQua main scientific and technical objective is to enhance the GEOSS Common Infrastructure (GCI) providing the user community with innovative quality-aware search and visualization tools, which will be integrated in the GEOPortal, as well as made available to other end-user interfaces. To this end, GeoViQua will promote the extension of the current standard metadata for geographic information with accurate and expressive quality indicators. Employing and extending several ISO standards such as 19115, 19157 and 19139, a common set of data quality indicators has been selected to be used within the project. The resulting work, in the form of a data model, is expressed in XML Schema Language and encoded in XML. Quality information can be stated both by data producers and by data users, actually resulting in two conceptually distinct data models, the Producer Quality model and the User Quality model (or User Feedback model). GeoViQua architecture is built on the brokering approach successfully experimented within the EuroGEOSS project and realized by the GEO DAB (Discovery and Access Broker) which is part of the GCI. The GEO DAB allows for harmonization and distribution in a transparent way for both users and data providers. This way, GeoViQua can effectively complement and extend the GEO DAB obtaining a Quality augmentation Broker (DAB-Q) which plays a central role in ensuring the consistency of the Producer and User quality models. The GeoViQua architecture also includes a Feedback Catalog, a particular service brokered by the DAB-Q which is dedicated to the storage and discovery of user feedbacks. A very important issue

  20. Spectrophotometric study of neptunium (VI) complexation by nitrate ions; Etude par spectrophotometrie de la complexation du neptunium au degre d'oxydation (VI) par les ions nitrates

    Energy Technology Data Exchange (ETDEWEB)

    Pochon, P. [CEA/VALRHO - site de Marcoule, Dept. de Recherche en Retraitement et en Vitrification (DRRV), 30 - Marcoule (France)]|[Conservatoire National des Arts et Metiers (CNAM), 75 - Paris (France)]|[Centre Regional Associe de Lyon, 69 (France)

    2000-07-01

    Neptunium(VI) complexation by nitrate ions was investigated by visible and near-infrared spectrophotometry, a technique suitable for observing the appearance and evolution of the species in solution. In the absence of reference spectra for Np(VI) nitrate- complexes, mathematical (factor analysis) tools were used to interpret the spectra. These chemo-metric techniques were first tested and validated on a simpler chemical system: Np(VI)complexation by the SiW{sub 11}O{sub 39}{sup 8-} anion. The test media used to investigate Np(VI) nitrate- complexes generally contain nitrate and perchlorate salts at high concentrations (high ionic strength). Media effects arising from the presence of cations, acidity or the perchlorate ion concentration are therefore significant, and no doubt account for the scattered values of the complexation constants published in the literature. The evolution of the neptunium spectra according to the parameters of the reaction medium illustrated these effects and allowed them to be quantified by a global 'perturbation constant'. In order to minimize the spectrum modifications due to media effects, the neptunium nitrate-complexes were studied at constant ionic strength in weak acidic media (2 mol.kg{sup -1}{sub H2O}) in the presence of sodium salts. The bulk formation constants and the spectrum of the NpO{sub 2}(NO{sub 3}){sup +} complex were determined for ionic strength values of 2.2, 4, 6 and 8 mol.kg{sup -1}{sub H2O}. The constants remained on the same order of magnitude regardless of the ionic strength; the thermodynamic constant {beta}{sub 1}{sup 0} determined from them according to specific interaction theory is thus probably of little significance. Conversely, the bulk constants can be corrected for the effects of the perchlorate ions by taking the global 'perturbation constant' into account. (author)

  1. Binary systems, star clusters and the Galactic-field population. Applied stellar dynamics

    Science.gov (United States)

    Kroupa, Pavel

    2002-01-01

    This book contains the results of recent theoretical work on the evolution of primordial binary systems in young star clusters, their effect on the evolution of their host clusters, implications for the distribution of young stars in the Milky Way, and the formation of bound star clusters. This work shows that if the Galactic-field binary population is a dynamically evolved version of the Taurus-Auriga pre-main sequence population, then most stars form in clusters with typically a few hundred binaries within a radius of about 0.5-1 pc. The results also suggest that the population I primordial binary-star orbital-parameter distribution functions may be universal, much like the initial mass function. Most solar-like planetary systems can survive in such clusters. The work presented here also establishes that most observed triple and quadruple systems must be primordial, but that α Cen A/B-Proxima Cen-like systems can form in clusters through dynamical capture. Precise N-body calculations using Aarseth's N-body codes of clusters containing up to 104 stars are used to create an extensive young-cluster library. These data demonstrate that the primordial binary systems are disrupted on a crossing-time scale, and that the truncation of the surviving period distribution measures the maximum concentration the cluster ever experienced. The N-body calculations demonstrate that Galactic star clusters form readily as nuclei of expanding OB associations despite a star-formation efficiency of typically 30 per cent and gas-expulsion over a time-span shorter than the cluster crossing time.

  2. Ingestion of chromium(VI) in drinking water by human volunteers: Absorption, distribution, and excretion of single and repeated doses

    Energy Technology Data Exchange (ETDEWEB)

    Kerger, B.D.; Corbett, G.E.; Dodge, D.G. [McLaren/Hart-ChemRisk, Irvine, CA (United States); Finley, B.L.; Paustenbach, D.J. [McLaren/Hart-ChemRisk, Alameda, CA (United States)] [and others

    1997-01-01

    This study examines the magnitude of hexavalent chromium [Cr(VI)] absorption, distribution, and excretion following oral exposure to 5 and 10 mg Cr(VI)/L in drinking water administered as a single bolus dose or for 3 d at a dosage of 1 L/d. Adult male volunteers were used. In the bolus dose studies, a fairly consistent pattern of urinary chromium excretion was observed, with an average half life of about 39 h. However, 4-d total urinary chromium excretion and peak concentrations in urine and blood varied considerably among the 5 volunteers. Studies of repeated exposure to small volumes ingested at a more gradual rate showed similar urinary chromium excretion patterns but generally lower chromium uptake/excretion. These data suggest that virtually all of the ingested Cr(VI) at 5 and 10 mg Cr(VI)/L was reduced to Cr(III) before entering the bloodstream. The interindividual differences in total chromium uptake and excretion are plausibly explained by ingestion of appreciable doses on an empty stomach, likely results in the formation of well-absorbed Cr(III) organic complexes. No clinical indications of toxicity in the volunteers and the patterns of blood uptake and urinary excretion of chromium are consistent with a predominant uptake of Cr(III) organic complexes that are excreted more slowly than inorganic forms of Cr(III). Therefore, it appears that the endogenous reducing agents within the upper gastrointestinal tract and the blood provide sufficient reducing potential to prevent any substantial systemic uptake of Cr(VI) following drinking-water exposures at 5-10 mg Cr(VI)/L. Based on these data, the chemical environment in the gastrointestinal tract and the blood is effective even under relative fasting condition in reducing Cr(VI) to one or more forms of Cr(III). 54 refs., 5 figs., 1 tab.

  3. The potential of compost-based biobarriers for Cr(VI) removal from contaminated groundwater: Column test

    International Nuclear Information System (INIS)

    Boni, Maria Rosaria; Sbaffoni, Silvia

    2009-01-01

    This paper presents the results of a column reactor test, aiming at evaluating the performance of a biological permeable barrier made of low-cost waste materials, for Cr(VI) removal from contaminated groundwater. A 1:1 by volume mixture of green compost and siliceous gravel was tested as reactive medium in the experimental activity. A 10 mg/l Cr(VI) contaminated solution was used and the residual Cr(VI) concentration along the column height and in the outlet was determined in the water samples collected daily. Also pH, redox potential and COD were analyzed. At the end of the test, the reactive medium was characterized in terms of Cr(VI) and total chromium. The Cr(VI) removal efficiency was higher than 99% during the entire experimental activity. The influence of the biological activity on Cr(VI) removal efficiency was evaluated by varying the organic carbon and nitrogen dosages in the contaminated solution fed to the system; a removal decrease was observed when the organic carbon was not enough to sustain the microbial metabolism. The Cr(VI) removal was strictly linked to the biological activity of the native biomass of compost. No Cr(III) was detected in the outlet: the Cr(III) produced was entrapped in the solid matrix. Two main processes involved were: adsorption on the organic-based matrix and reduction into Cr(III) mediated by the anaerobic microbial metabolism of the bacteria residing in green compost. Siliceous gravel was used as the structure matrix, since its contribution to the removal was almost negligible. Thanks to the proven efficiency and to the low-cost, the reactive medium used can represent a valid alternative to conventional approaches to chromium remediation.

  4. Mating system in a natural population of Theobroma grandiflorum (Willd. ex Spreng. Schum., by microsatellite markers

    Directory of Open Access Journals (Sweden)

    Alves Rafael M.

    2003-01-01

    Full Text Available The aim of this research was to study the mating system of a natural population of Theobroma grandiflorum (cupuassu from Nova Ipixuna, Pará state, using microsatellite markers. Eight polymorphic microsatellite loci were analyzed in eight families, each represented by 10 six-month old seedlings derived from open-pollinated pods. The estimation for the multilocus outcrossing rate (m = 1.0 and individual outcrossing rate ( = 1.0 for this population suggests that T. grandiflorum may be a perfect outbreeding (allogamous species. Likewise, for the studied population the estimate for single locus outcrossing rate (S was elevated (0.946, but lower than m, confirming the likely outcrossing character of the species and suggesting the occurrence of 5.4% biparental inbreeding rate (m - S. The estimation of genetic divergence (st between allelic frequencies in ovules and pollen revealed a deviation from random mating in 75% of the evaluated loci. Likewise, the estimate of correlation of paternity (P = 0.930 and the mean coefficient of co-ancestrality within families (XY = 0.501 indicated that the outcrossings were predominantly correlated, and the offspring were full-sibs. These results suggested that for this particular population of T. grandiflorum, the sampling strategy for genetic conservation and breeding should adopt specific models for families derived from correlated outcrossing (full-sibs and not the ones usually adopted in classic outcrossing species breeding programs (half-sibs.

  5. Comparative morphometry of facial surface models obtained from a stereo vision system in a healthy population

    Science.gov (United States)

    López, Leticia; Gastélum, Alfonso; Chan, Yuk Hin; Delmas, Patrice; Escorcia, Lilia; Márquez, Jorge

    2014-11-01

    Our goal is to obtain three-dimensional measurements of craniofacial morphology in a healthy population, using standard landmarks established by a physical-anthropology specialist and picked from computer reconstructions of the face of each subject. To do this, we designed a multi-stereo vision system that will be used to create a data base of human faces surfaces from a healthy population, for eventual applications in medicine, forensic sciences and anthropology. The acquisition process consists of obtaining the depth map information from three points of views, each depth map is obtained from a calibrated pair of cameras. The depth maps are used to build a complete, frontal, triangular-surface representation of the subject face. The triangular surface is used to locate the landmarks and the measurements are analyzed with a MATLAB script. The classification of the subjects was done with the aid of a specialist anthropologist that defines specific subject indices, according to the lengths, areas, ratios, etc., of the different structures and the relationships among facial features. We studied a healthy population and the indices from this population will be used to obtain representative averages that later help with the study and classification of possible pathologies.

  6. BSim: an agent-based tool for modeling bacterial populations in systems and synthetic biology.

    Directory of Open Access Journals (Sweden)

    Thomas E Gorochowski

    Full Text Available Large-scale collective behaviors such as synchronization and coordination spontaneously arise in many bacterial populations. With systems biology attempting to understand these phenomena, and synthetic biology opening up the possibility of engineering them for our own benefit, there is growing interest in how bacterial populations are best modeled. Here we introduce BSim, a highly flexible agent-based computational tool for analyzing the relationships between single-cell dynamics and population level features. BSim includes reference implementations of many bacterial traits to enable the quick development of new models partially built from existing ones. Unlike existing modeling tools, BSim fully considers spatial aspects of a model allowing for the description of intricate micro-scale structures, enabling the modeling of bacterial behavior in more realistic three-dimensional, complex environments. The new opportunities that BSim opens are illustrated through several diverse examples covering: spatial multicellular computing, modeling complex environments, population dynamics of the lac operon, and the synchronization of genetic oscillators. BSim is open source software that is freely available from http://bsim-bccs.sf.net and distributed under the Open Source Initiative (OSI recognized MIT license. Developer documentation and a wide range of example simulations are also available from the website. BSim requires Java version 1.6 or higher.

  7. 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......, the current iteration of the Social Set Visualizer (SoSeVi) in version II builds on recent advancements in visualizing set intersections. The development of the SoSeVi dashboard involved cutting-edge open source visual analytics libraries (D3.js) and creation of new visualizations such as of actor mobility...

  8. Comparison of soil surface arthropod populations in conventional tillage, no-tillage and old field systems

    Energy Technology Data Exchange (ETDEWEB)

    Blumberg, A Y; Crossley, Jr, D A

    1980-08-01

    Soil surface arthropod populations in conventional tillage (CT) and no-tillage (NT) sorghum and adjacent old field (OF) were compared using pitfall trap captures. Total numbers of individuals and species, overall diversity (anti H), richness (D), evenness (J'), dominance (C) and similarity quotients (QS) between systems were calculated for each of seven 24 hour sampling periods throughout the season. Although each system was distinct (any two of the systems had less than 30 percent of their species in common), NT was most similar to OF and least similar to CT during a period of stress (drought) and after heading of the sorghum. Percentages of individuals and species represented by spiders were similar in NT and OF; percentages were substantially less in CT. Yields (biomass of sorghum) in CT and NT were not significantly different despite the generally predicted higher pest populations in NT. Results suggest that insecticide stress may lower the stability of NT systems, thus allowing an increase in pest species.

  9. Molecular genetic variability, population structure and mating system in tropical forages

    Directory of Open Access Journals (Sweden)

    Melissa Garcia

    2013-09-01

    Full Text Available Microsatellite (SSR markers were developed for the following tropical forage species, using accessions available from the plant genetic resources (PGR collections held by EMBRAPA (Brazilian Agricultural Research Corporation: Brachiaria brizantha, B. humidicola, Panicum maximum, Paspalum spp., Stylosanthes capitata, S. guianensis, S. macrocephala, Calopogonium mucunoides and Centrosema spp. The markers were used to analyze population structure and genetic diversity, evolution and origin of the genetic variability in the center of origin, mating systems and genetic resources in EMBRAPA’s germplasm bank. The results shed light on the amount of genetic variation within and between populations, revealed the need in some cases for further plant collection to adequately represent the species in PGR collections, allowed us to assemble core collections (subsets of the total collections that should contain most of the available diversity and (in the case of the legumes showed the need to avoid unwanted outcrossing when regenerating conserved material. The data will allow plant breeders to better select accessions for hybrid production, discriminate between genotypes and use marker-assisted selection in breeding programs. Our results will also underpin the construction of genetic maps, mapping of genes of agronomic interest and numerous other studies on genetic variability, population structure, gene flow and reproductive systems for the tropical forage species studied in this work.

  10. Implications of Changes in Water Use, Population, and Climate on Performance and Planning of Wastewater Systems

    Science.gov (United States)

    Cook, L. M.; Samaras, C.; VanBriesen, J.

    2016-12-01

    The installation of water-efficient indoor appliances and fixtures - such as those meeting standards set by the 1992 Energy Policy Act - has led to a significant decline in residential water use over the past 30 years. Other water conservation strategies, like leak repair and greywater reuse, have also contributed to changes in the amount of potable water used by cities. These changes affect downstream systems like wastewater collection and treatment. During the 1970s drought in California, mandatory water conservation measures led to a reduction in wastewater flows by up to 60%, leading to an increase in pipe corrosion, solids settling, and odor due to lower flow velocities. Performance and design of wastewater systems over time is, however, a complex system affected by external drivers, like climate, population and land use, policy and public changes that influence water use, and water utility practices such as maintenance and green infrastructure installation that can reduce flows into the system. This research demonstrates how the use of active water management, e.g. measures that increase water use efficiency or decrease the amount of infiltration and inflow (I&I), may help offset exogenous factors, preventing or delaying the need for upgrades to existing water infrastructure systems. This is evaluated through a scenario analysis of flows to a wastewater treatment Plant, located in Portland, Oregon. Future wastewater flows were projected to 2040 using potential changes in per capita wastewater production, industrial wastewater production, population growth, and ranges of infiltration and inflow. Results show that with current efficiency trends in Portland, rapid population growth could be offset, leading to stabilization of wastewater flows over the next several decades, and elimination of the need for capital expansion. Climate drivers leading to an increase in stormwater inflows have the potential to outweigh declines in wastewater due to efficiency; yet the

  11. 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

  12. Ocular inflammation in the setting of concomitant systemic autoimmune conditions in an older male population

    Science.gov (United States)

    Levitt, Alexandra E.; McManus, Katherine T.; McClellan, Allison L.; Davis, Janet; Goldhardt, Raquel; Galor, Anat

    2015-01-01

    Purpose This retrospective cross-sectional study was designed to investigate the frequency and types of inflammatory ocular manifestations of specific systemic autoimmune diseases in a South Florida Veterans Affairs Hospital population. Methods Demographic and medical diagnosis information was extracted from the Veterans Administration database for 1225 patients. These patients were seen in Miami and Broward Veterans Affairs hospitals between 4/18/2008 and 4/17/2013 and were diagnosed with at least one of the following: systemic lupus erythematosus, sarcoid, rheumatoid arthritis, polymyalgia rheumatica, Takayasu arteritis, giant cell arteritis, Kawasaki disease, polyarteritis nodosa, Buerger disease, Henoch-Schonlein purpura, Behcet syndrome, granulomatosis with polyangiitis, other polyarteritis nodosa associated vasculitides, or arteritis NOS. Results Of 1225 patients, 618 were seen in the VA eye clinic, and 25 were diagnosed with concomitant inflammatory ocular conditions. Uveitis was the most common, and included 8 cases of anterior, 1 anterior-intermediate, 1 intermediate, 2 panuveitis, and 3 unspecified. Other manifestations included 7 cases of keratitis and 2 each of scleritis, episcleritis and AION. The overall frequency of inflammatory ocular disease was 2%. The diseases associated with the highest frequency of ocular involvement were granulomatosis with polyangiitis (1/8), sarcoid (9/198), giant cell arteritis (2/68), and rheumatoid arthritis (11/576). Of these 25 patients, 9 were diagnosed with eye prior to systemic disease. Conclusions In this population, ocular manifestations were rarely the presenting feature of systemic disease, but autoimmune disorders are an important underlying cause of inflammatory eye disease that should be considered on first evaluation, even in this “non-traditional”, predominantly male, autoimmune disease population. PMID:26053887

  13. 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

  14. 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

  15. KENO3D Visualization Tool for KENO V.a and KENO-VI Geometry Models

    International Nuclear Information System (INIS)

    Horwedel, J.E.; Bowman, S.M.

    2000-01-01

    Criticality safety analyses often require detailed modeling of complex geometries. Effective visualization tools can enhance checking the accuracy of these models. This report describes the KENO3D visualization tool developed at the Oak Ridge National Laboratory (ORNL) to provide visualization of KENO V.a and KENO-VI criticality safety models. The development of KENO3D is part of the current efforts to enhance the SCALE (Standardized Computer Analyses for Licensing Evaluations) computer software system

  16. (VI) from water by micro-alloyed aluminium composite (MAlC)

    African Journals Online (AJOL)

    driniev

    2004-07-03

    Jul 3, 2004 ... on processes of reduction and co-precipitation by Al(OH)3, because Cr(VI) is removed from the water phase as metal chromium and insoluble .... (MB) made of high-density polyethylene, held a volume of 10.0 l. Figure 1. A model of the .... Schematic diagram of the original semi-flow system. 0. 15. 30. 45. 60.

  17. UnoViS: the MedIT public unobtrusive vital signs database

    OpenAIRE

    Wartzek, Tobias; Czaplik, Michael; Antink, Christoph Hoog; Eilebrecht, Benjamin; Walocha, Rafael; Leonhardt, Steffen

    2015-01-01

    While PhysioNet is a large database for standard clinical vital signs measurements, such a database does not exist for unobtrusively measured signals. This inhibits progress in the vital area of signal processing for unobtrusive medical monitoring as not everybody owns the specific measurement systems to acquire signals. Furthermore, if no common database exists, a comparison between different signal processing approaches is not possible. This gap will be closed by our UnoViS database. It con...

  18. In situ examination of microbial populations in a model drinking water distribution system

    DEFF Research Database (Denmark)

    Martiny, Adam Camillo; Nielsen, Alex Toftgaard; Arvin, Erik

    2002-01-01

    A flow cell set-up was used as a model drinking water distribution system to analyze the in situ microbial population. Biofilm growth was followed by transmission light microscopy for 81 days and showed a biofilm consisting of microcolonies separated by a monolayer of cells. Protozoans (ciliates...... revealed that the majority of the isolated strains from the bulk water and biofilm were affiliated to the family of Comamonadaceae in the β-lineage of Proteobacteria. The majority of the strains from the α-lineage were affiliated to the family of Sphingomonadaceae. We were unable to detect any strains from...... of a mixed population of α- and β-Proteobacteria. 65 strains from the inlet water and 20 from the biofilm were isolated on R2A agar plates and sorted into groups with amplified rDNA restriction analysis. The 16S rDNA gene was sequenced for representatives of the abundant groups. A phylogenetic analysis...

  19. Achieving Population-Level Change Through a System-Contextual Approach to Supporting Competent Parenting.

    Science.gov (United States)

    Sanders, Matthew R; Burke, Kylie; Prinz, Ronald J; Morawska, Alina

    2017-03-01

    The quality of parenting children receive affects a diverse range of child and youth outcomes. Addressing the quality of parenting on a broad scale is a critical part of producing a more nurturing society. To achieve a meaningful population-level reduction in the prevalence rates of child maltreatment and social and emotional problems that are directly or indirectly influenced by parenting practices requires the adoption of a broad ecological perspective in supporting families to raise children. We make the case for adopting a multilevel, whole of population approach to enhance competent parenting and describe the essential tasks that must be accomplished for the approach to be successful and its effects measurable. We describe how a theoretically integrated system of parenting support based on social learning and cognitive behavioral principles can be further strengthened when the broader community supports parental participation. Implications for policy and practice are discussed.

  20. In situ examination of microbial populations in a model drinking water distribution system

    DEFF Research Database (Denmark)

    Martiny, Adam Camillo; Nielsen, Alex Toftgaard; Arvin, Erik

    2002-01-01

    A flow cell set-up was used as a model drinking water distribution system to analyze the in situ microbial population. Biofilm growth was followed by transmission light microscopy for 81 days and showed a biofilm consisting of microcolonies separated by a monolayer of cells. Protozoans (ciliates...... of a mixed population of α- and β-Proteobacteria. 65 strains from the inlet water and 20 from the biofilm were isolated on R2A agar plates and sorted into groups with amplified rDNA restriction analysis. The 16S rDNA gene was sequenced for representatives of the abundant groups. A phylogenetic analysis...... revealed that the majority of the isolated strains from the bulk water and biofilm were affiliated to the family of Comamonadaceae in the β-lineage of Proteobacteria. The majority of the strains from the α-lineage were affiliated to the family of Sphingomonadaceae. We were unable to detect any strains from...

  1. Global Existence Analysis of Cross-Diffusion Population Systems for Multiple Species

    Science.gov (United States)

    Chen, Xiuqing; Daus, Esther S.; Jüngel, Ansgar

    2018-02-01

    The existence of global-in-time weak solutions to reaction-cross-diffusion systems for an arbitrary number of competing population species is proved. The equations can be derived from an on-lattice random-walk model with general transition rates. In the case of linear transition rates, it extends the two-species population model of Shigesada, Kawasaki, and Teramoto. The equations are considered in a bounded domain with homogeneous Neumann boundary conditions. The existence proof is based on a refined entropy method and a new approximation scheme. Global existence follows under a detailed balance or weak cross-diffusion condition. The detailed balance condition is related to the symmetry of the mobility matrix, which mirrors Onsager's principle in thermodynamics. Under detailed balance (and without reaction) the entropy is nonincreasing in time, but counter-examples show that the entropy may increase initially if detailed balance does not hold.

  2. The Relationship between Mating System and Genetic Diversity in Diploid Sexual Populations of Cyrtomium falcatum in Japan.

    Directory of Open Access Journals (Sweden)

    Ryosuke Imai

    Full Text Available The impact of variation in mating system on genetic diversity is a well-debated topic in evolutionary biology. The diploid sexual race of Cyrtomium falcatum (Japanese holly fern shows mating system variation, i.e., it displays two different types of sexual expression (gametangia formation in gametophytes: mixed (M type and separate (S type. We examined whether there is variation in the selfing rate among populations of this species, and evaluated the relationship between mating system, genetic diversity and effective population size using microsatellites. In this study, we developed eight new microsatellite markers and evaluated genetic diversity and structure of seven populations (four M-type and three S-type. Past effective population sizes (Ne were inferred using Approximate Bayesian computation (ABC. The values of fixation index (FIS, allelic richness (AR and gene diversity (h differed significantly between the M-type (FIS: 0.626, AR: 1.999, h: 0.152 and the S-type (FIS: 0.208, AR: 2.718, h: 0.367 populations (when admixed individuals were removed from two populations. Although evidence of past bottleneck events was detected in all populations by ABC, the current Ne of the M-type populations was about a third of that of the S-type populations. These results suggest that the M-type populations have experienced more frequent bottlenecks, which could be related to their higher colonization ability via gametophytic selfing. Although high population differentiation among populations was detected (FST = 0.581, F'ST = 0.739, there was no clear genetic differentiation between the M- and S-types. Instead, significant isolation by distance was detected among all populations. These results suggest that mating system variation in this species is generated by the selection for single spore colonization during local extinction and recolonization events and there is no genetic structure due to mating system.

  3. The Relationship between Mating System and Genetic Diversity in Diploid Sexual Populations of Cyrtomium falcatum in Japan.

    Science.gov (United States)

    Imai, Ryosuke; Tsuda, Yoshiaki; Matsumoto, Sadamu; Ebihara, Atsushi; Watano, Yasuyuki

    2016-01-01

    The impact of variation in mating system on genetic diversity is a well-debated topic in evolutionary biology. The diploid sexual race of Cyrtomium falcatum (Japanese holly fern) shows mating system variation, i.e., it displays two different types of sexual expression (gametangia formation) in gametophytes: mixed (M) type and separate (S) type. We examined whether there is variation in the selfing rate among populations of this species, and evaluated the relationship between mating system, genetic diversity and effective population size using microsatellites. In this study, we developed eight new microsatellite markers and evaluated genetic diversity and structure of seven populations (four M-type and three S-type). Past effective population sizes (Ne) were inferred using Approximate Bayesian computation (ABC). The values of fixation index (FIS), allelic richness (AR) and gene diversity (h) differed significantly between the M-type (FIS: 0.626, AR: 1.999, h: 0.152) and the S-type (FIS: 0.208, AR: 2.718, h: 0.367) populations (when admixed individuals were removed from two populations). Although evidence of past bottleneck events was detected in all populations by ABC, the current Ne of the M-type populations was about a third of that of the S-type populations. These results suggest that the M-type populations have experienced more frequent bottlenecks, which could be related to their higher colonization ability via gametophytic selfing. Although high population differentiation among populations was detected (FST = 0.581, F'ST = 0.739), there was no clear genetic differentiation between the M- and S-types. Instead, significant isolation by distance was detected among all populations. These results suggest that mating system variation in this species is generated by the selection for single spore colonization during local extinction and recolonization events and there is no genetic structure due to mating system.

  4. Security of the Population in the Czech Republic from the Aaspect of Crime and Penitentiary System

    Directory of Open Access Journals (Sweden)

    Jiří Kamenický

    2013-09-01

    Full Text Available Th e empirical study concerning wide area of security of the Czech population deals with both its aspects –crime and prison population. First, we have the picture of macro-economic view on the issues through theinternational comparison of government expenditures on individual areas of public order and security. Morecomprehensive part of the paper maps out the development of registered and cleared-up crime in the CzechRepublic by main types, it pays attention to selected groups of perpetrators (children, juveniles, criminal repeatersand also its signifi cant regional dimensions, including attempts to explain it. Overwhelming quantitativeview on crime is extended also by subjective evaluation of security of population near their residence.Signifi cance of qualitative view increases mainly in attempt to make international comparison where traditional“hard“ data on crime hit diff erent legal environment also in geographically close countries within theEU. Social pathology and criminal legislation infl uence also the composition of prison population which isassessed from the aspect of sex, age, citizenship, education, the level of imposed sentence and criminal history.Increasing number of prisoners has recently negatively infl uenced the occupancy rate of prisons, which raisesquestions concerning sustainability of fi nancing of penitentiary system especially in the period of total economicdepression. Presidential amnesty in January 2013 released more than a quarter of all prisoners whichresulted in one-shot signifi cant decrease in occupancy rate. Th is event modifi ed also the structure of prisonpopulation. Th e position of the Czech Republic within EU improved signifi cantly in terms of occupancy rate,but still remained unfavourable as regards total rate of imprisonment of population.

  5. Population-Based Study to Determine the Health System Costs of Using the 21-Gene Assay.

    Science.gov (United States)

    Mittmann, Nicole; Earle, Craig C; Cheng, Stephanie Y; Julian, Jim A; Rahman, Farah; Seung, Soo Jin; Levine, Mark N

    2018-01-20

    Purpose The 21-gene assay Oncotype Dx (Genomic Health, Redwood City, CA) test is used to aid the decision about chemotherapy in patients with hormone receptor-positive breast cancer who received endocrine therapy. Economic studies to support test adoption used decision-analytic models with assumptions and data derived from disparate sources. The objective was to evaluate whether the 21-gene assay test resulted in an overall cost expense or saving to the health system. Patients and Methods One thousand participants enrolled in a field evaluation study, were linked to population-level health system administrative databases, and were observed for 20 months. The cost for the cohort, which included the cost of the test, subsequent treatments received, and health care encounters, was determined. The cost in the absence of the test was compared with the pretest recommendation about chemotherapy from the field study for a base case and under scenarios that reflected different adjuvant chemotherapy use. Overall health system costs and incremental costs were calculated. Results The 21-gene assay resulted in a net decrease in chemotherapy use of 23%. For the base case incremental analysis, the actual overall health system cost of this cohort, including the cost of 21-gene assay, was $29.2 million compared with $26.2 million in the absence of the test-an increase of $3.1 million. For three of the four scenario analyses, the actual overall cost to the health system exceeded the estimated cost in the absence of the test. Results showed that, when at least half of the population received adjuvant chemotherapy, the cost increased to $30.2 million. Conclusion The use of real-world administrative data showed that, despite lower rates of chemotherapy use, the 21-gene assay test results in an overall incremental cost to the health care system in the short-term under most assumptions.

  6. Chromium isotope inventory of Cr(VI)-polluted groundwaters at four industrial sites in Central Europe

    Science.gov (United States)

    Novak, Martin; Martinkova, Eva; Chrastny, Vladislav; Stepanova, Marketa; Curik, Jan; Szurmanova, Zdenka; Cron, Marcel; Tylcer, Jiri; Sebek, Ondrej

    2016-04-01

    Chromium is one of the most toxic elements, especially in its dissolved Cr(VI) form. In the Czech Republic (Central Europe), massive contamination of groundwater has been reported at more than 200 industrial operations. Under suitable conditions, i.e., low Eh, and high availability of reductive agents, Cr(VI) in groundwater may be spontaneously reduced to solid, largely non-toxic Cr(III). This process is associated with a Cr isotope fractionation, with the residual liquid Cr(VI) becoming enriched in the heavier isotope 53Cr. At industrial operations that have been closed and/or where no further leakage of Cr(VI) occurs, the contaminated groundwater plume may be viewed as a closed system. At such sites, an increasing degree of Cr(VI) reduction should result in an increasing del53/52Cr value of the residual liquid. Here we present del53/52Cr systematics at four contaminated Czech sites, focusing on groundwaters. At two of the four sites (Zlate Hory, Loucna) we were also able to analyze the source of contamination. Chromium in the electroplating solutes was isotopically relatively light, with del53/52Cr values 4.0 per mil (mean of +1.7 per mil); at Letnany, del53/52Cr ranged between +2.0 and +4.5 per mil (mean of +3.2 per mil); and at Velesin, del53/52Cr ranged between +0.5 and +4.5 per mil (mean of +2.7 per mil). Cr(VI) reduction may proceed at Zlate Hory and Loucna, where del53/52Cr(VI) values in groundwater were on average higher than those of the contamination source. At these two sites, our Cr isotope data are not consistent with the existing estimates of the amount of dissolved and precipitated Cr: The pool size of solid Cr(III) in the soil was estimated at 6600 and 500 kg at Zlate Hory and Loucna, respectively. At the same time, the pool size of dissolved Cr(VI) was estimated at 50 and 1.2 kg at Zlate Hory and Loucna, respectively. It follows that, at both sites, less than 1 % of the entire Cr that had leaked into the aquifer an a liquid form remained in the

  7. 2-(2'-pyridyl) benzimidazole complexes of dioxouranium (VI) and thorium(VI)

    International Nuclear Information System (INIS)

    Dash, K.C.; Mohanta, H.

    1978-01-01

    The bidentate ligand, 2-(2'-pyridyl) benzimidazole (PBH), forms a variety of complexes with dioxouranium(VI) and thorium(IV) of the type, U0 2 (PBH)sub(n)X 2 (n = l, X Cl, I, NO 3 , O.5SO 4 : n = 2, X = NCS), UO 2 (PBH) 3 (ClO 4 ) 2 , Th(PBH) 2 X 4 = Cl, NCS, NO 3 ) and Th(PBH) 4 (ClO 4 ) 4 . Microanalysis, electric conductivity in various non-aqueous media, electronic and IR (down to 200 cm -1 ) spectra, mass spectra and the TGA, DTA measurements on the complexes are reported. (author)

  8. Evaluation of the bioremoval of Cr(VI) and TOC in biofilters under continuous operation using response surface methodology.

    Science.gov (United States)

    Leles, Daniela M A; Lemos, Diego A; Filho, Ubirajara C; Romanielo, Lucienne L; de Resende, Miriam M; Cardoso, Vicelma L

    2012-06-01

    In the present study, the bioremoval of Cr(VI) and the removal of total organic carbon (TOC) were achieved with a system composed by an anaerobic filter and a submerged biofilter with intermittent aeration using a mixed culture of microorganisms originating from contaminated sludge. In the aforementioned biofilters, the concentrations of chromium, carbon, and nitrogen were optimized according to response surface methodology. The initial concentration of Cr(VI) was 137.35 mg l(-1), and a bioremoval of 85.23% was attained. The optimal conditions for the removal of TOC were 4 to 8 g l(-1) of sodium acetate, >0.8 g l(-1) of ammonium chloride and 60 to 100 mg l(-1) of Cr(VI). The results revealed that ammonium chloride had the strongest effect on the TOC removal, and 120 mg l(-1) of Cr(VI) could be removed after 156 h of operation. Moreover, 100% of the Cr(VI) and the total chromium content of the aerobic reactor output were removed, and TOC removals of 80 and 87% were attained after operating the anaerobic and aerobic reactors for 130 and 142 h, respectively. The concentrations of cells in both reactors remained nearly constant over time. The residence time distribution was obtained to evaluate the flow through the bioreactors.

  9. Mechanism of uranium (VI) removal by two anaerobic bacterial communities

    International Nuclear Information System (INIS)

    Martins, Monica; Faleiro, Maria Leonor; Costa, Ana M. Rosa da; Chaves, Sandra; Tenreiro, Rogerio; Matos, Antonio Pedro; Costa, Maria Clara

    2010-01-01

    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.

  10. Vi tar pulsen på trærne

    OpenAIRE

    Børja, Isabella; Clarke, Nicholas; Dreslerová, J; Eldhuset, Toril Drabløs; Gebauer, Roman; Gryc, V; Krokene, Paal; Nagy, Nina Elisabeth; Urban, J; Volařík, Daniel

    2010-01-01

    Tørkestress hos gran ser ut til å bli et stadig større problem i mange europeiske land. På Skog og landskap har vi et EØS-samarbeidsprosjekt med tsjekkiske forskere fra Mendel-universitetet i Brno hvor vi i detalj undersøker hva som skjer i tørkestressede grantrær. Målet er å kartlegge vannførende mekanismer hos trær som er tørkestresset. Vi arbeider med 20 år gamle kloner av gran og simulerer tørke ved å bygge et tak under trekronene. Her bruker vi avansert instrumentering for å følge med på...

  11. 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.

  12. The rural bite in population pyramids: what are the implications for responsiveness of health systems in middle income countries?

    Science.gov (United States)

    2014-01-01

    Background Health services can only be responsive if they are designed to service the needs of the population at hand. In many low and middle income countries, the rate of urbanisation can leave the profile of the rural population quite different from the urban population. As a consequence, the kinds of services required for an urban population may be quite different from that required for a rural population. This is examined using data from the South East Asia Community Observatory in rural Malaysia and contrasting it with the national Malaysia population profile. Methods Census data were collected from 10,373 household and the sex and age of household members was recorded. Approximate Malaysian national age and sex profiles were downloaded from the US Census Bureau. The population pyramids, and the dependency and support ratios for the whole population and the SEACO sub-district population are compared. Results Based on the population profiles and the dependency ratios, the rural sub-district shows need for health services in the under 14 age group similar to that required nationally. In the older age group, however, the rural sub-district shows twice the need for services as the national data indicate. Conclusion The health services needs of an older population will tend towards chronic conditions, rather than the typically acute conditions of childhood. The relatively greater number of older people in the rural population suggest a very different health services mix need. Community based population monitoring provides critical information to inform health systems. PMID:25081203

  13. The rural bite in population pyramids: what are the implications for responsiveness of health systems in middle income countries?

    Science.gov (United States)

    Jahan, Nowrozy; Allotey, Pascale; Arunachalam, Dharma; Yasin, Shajahan; Soyiri, Ireneous N; Davey, Tamzyn M; Reidpath, Daniel D

    2014-01-01

    Health services can only be responsive if they are designed to service the needs of the population at hand. In many low and middle income countries, the rate of urbanisation can leave the profile of the rural population quite different from the urban population. As a consequence, the kinds of services required for an urban population may be quite different from that required for a rural population. This is examined using data from the South East Asia Community Observatory in rural Malaysia and contrasting it with the national Malaysia population profile. Census data were collected from 10,373 household and the sex and age of household members was recorded. Approximate Malaysian national age and sex profiles were downloaded from the US Census Bureau. The population pyramids, and the dependency and support ratios for the whole population and the SEACO sub-district population are compared. Based on the population profiles and the dependency ratios, the rural sub-district shows need for health services in the under 14 age group similar to that required nationally. In the older age group, however, the rural sub-district shows twice the need for services as the national data indicate. The health services needs of an older population will tend towards chronic conditions, rather than the typically acute conditions of childhood. The relatively greater number of older people in the rural population suggest a very different health services mix need. Community based population monitoring provides critical information to inform health systems.

  14. A system dynamics optimization framework to achieve population desired of average weight target

    Science.gov (United States)

    Abidin, Norhaslinda Zainal; Zulkepli, Jafri Haji; Zaibidi, Nerda Zura

    2017-11-01

    Obesity is becoming a serious problem in Malaysia as it has been rated as the highest among Asian countries. The aim of the paper is to propose a system dynamics (SD) optimization framework to achieve population desired weight target based on the changes in physical activity behavior and its association to weight and obesity. The system dynamics approach of stocks and flows diagram was used to quantitatively model the impact of both behavior on the population's weight and obesity trends. This work seems to bring this idea together and highlighting the interdependence of the various aspects of eating and physical activity behavior on the complex of human weight regulation system. The model was used as an experimentation vehicle to investigate the impacts of changes in physical activity on weight and prevalence of obesity implications. This framework paper provides evidence on the usefulness of SD optimization as a strategic decision making approach to assist in decision making related to obesity prevention. SD applied in this research is relatively new in Malaysia and has a high potential to apply to any feedback models that address the behavior cause to obesity.

  15. A population-based evaluation of the seventh edition of the TNM system for lung cancer

    DEFF Research Database (Denmark)

    Strand, T-E; Rostad, H; Wentzel-Larsen, T

    2010-01-01

    Our study describes the new seventh edition of the TNM system for lung cancer in a national population and its clinical implications. We classified 1,885 operated patients with lung cancer, reported to the Cancer Registry of Norway (Oslo, Norway) from 2001 to 2005, according to the sixth and the ......Our study describes the new seventh edition of the TNM system for lung cancer in a national population and its clinical implications. We classified 1,885 operated patients with lung cancer, reported to the Cancer Registry of Norway (Oslo, Norway) from 2001 to 2005, according to the sixth...... to stage II and 161 (48%) patients migrated from stage IIB to IIA. Stage migrations could change the treatment for up to 326 (17.3%) of the study patients. The seventh edition did not improve the overall predictive ability of the TNM system; however, the new classification implies changes in treatment...... for nearly one-fifth of the cases. The implications of the seventh TNM edition for the outcomes of patients should be studied further....

  16. Reaction rate constants and mean population percentage for nitrifiers in an alternating oxidation ditch system.

    Science.gov (United States)

    Mantziaras, I D; Katsiri, A

    2011-01-01

    This paper presents a methodology for the determination of reaction rate constants for nitrifying bacteria and their mean population percentage in biomass in an alternating oxidation ditch system. The method used is based on the growth rate equations of the ASM1 model (IWA) (Henze et al. in Activated sludge models ASM1, ASM2, ASM2d, and ASM3. IWA Scientific and Technical Report no. 9, IWA Publishing, London, UK, 2000) and the application of mass balance equations for nitrifiers and ammonium nitrogen in an operational cycle of the ditch system. The system consists of two ditches operating in four phases. Data from a large-scale oxidation ditch pilot plant with a total volume of 120 m(3) within an experimental period of 8 months was used. Maximum specific growth rate for autotrophs (μ(A)) and the half-saturation constant for ammonium nitrogen (K(NH)) were found to be 0.36 day(-1) and 0.65 mgNH(4)-N/l, respectively. Additionally, the average population percentage of the nitrifiers in the biomass was estimated to be around 3%.

  17. Effect of microstructure on population growth parameters of Escherichia coli in gelatin-dextran systems.

    Science.gov (United States)

    Boons, Kathleen; Noriega, Estefanía; Van den Broeck, Rob; David, Charlotte C; Hofkens, Johan; Van Impe, Jan F

    2014-09-01

    Current literature acknowledges the effect of food structure on bacterial dynamics. Most studies introduce this "structure" factor using a single gelling agent, resulting in a homogeneous environment, whereas in practice most food products are heterogeneous. Therefore, this study focuses on heterogeneous protein-polysaccharide mixtures, based on gelatin and dextran. These mixtures show phase separation, leading to a range of heterogeneous microstructures by adjusting relative concentrations of both gelling agents. Based on confocal microscope observations, the growth of Escherichia coli in gelatin-dextran systems was observed to occur in the dextran phase. To find a relation between microscopic and population behavior, growth experiments were performed in binary and singular gelatin-dextran systems and culture broth at 23.5°C, with or without adding 2.9% (wt/vol) NaCl. The Baranyi and Roberts growth model was fitted to the experimental data and parameter estimates were statistically compared. For salted binary mixtures, a decrease in the population maximum cell density was observed with increasing gelatin concentration. In this series, for one type of microstructure, i.e., a gelatin matrix phase with a disperse dextran phase, the maximum cell density decreased with decreasing percentage of dextran phase. However, this relation no longer held when other types of microstructure were observed. Compared to singular systems, adding a second gelling agent in the presence of NaCl had an effect on population lag phases and maximum cell densities. For unsalted media, the growth parameters of singular and binary mixtures were comparable. Introducing this information into mathematical models leads to more reliable growth predictions and enhanced food safety. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  18. A fetal whole ovarian culture model for the evaluation of CrVI-induced developmental toxicity during germ cell nest breakdown

    International Nuclear Information System (INIS)

    Stanley, Jone A.; Arosh, Joe A.; Burghardt, Robert C.; Banu, Sakhila K.

    2015-01-01

    Prenatal exposure to endocrine disrupting chemicals (EDCs), including bisphenol A, dioxin, pesticides, and cigarette smoke, has been linked to several ovarian diseases such as premature ovarian failure (POF) and early menopause in women. Hexavalent chromium (CrVI), one of the more toxic heavy metals, is widely used in more than 50 industries. As one of the world's leading producers of Cr compounds, the U.S. is facing growing challenges in protecting human health against adverse effects of CrVI. Our recent findings demonstrated that in vivo CrVI exposure during gestational period caused POF in F1 offspring. Our current research focus is three-fold: (i) to identify the effect of CrVI on critical windows of great vulnerability of fetal ovarian development; (ii) to understand the molecular mechanism of CrVI-induced POF; (iii) to identify potential intervention strategies to mitigate or inhibit CrVI effects. In order to accomplish these goals we used a fetal whole ovarian culture system. Fetuses were removed from the normal pregnant rats on gestational day 13.5. Fetal ovaries were cultured in vitro for 12 days, and treated with or without 0.1 ppm potassium dichromate (CrVI) from culture day 2–8, which recapitulated embryonic day 14.5–20.5, in vivo. Results showed that CrVI increased germ cell/oocyte apoptosis by increasing caspase 3, BAX, p53 and PUMA; decreasing BCL2, BMP15, GDF9 and cKIT; and altering cell cycle regulatory genes and proteins. This model system may serve as a potential tool for high throughput testing of various drugs and/or EDCs in particular to assess developmental toxicity of the ovary. - Highlights: • CrVI (0.1 ppm, a regulatory dose) increased germ cell apoptosis of fetal ovaries. • CrVI (0.1 ppm) increased pro-apoptotic proteins. • CrVI (0.1 ppm) decreased cyclins and CDK1 and cell survival proteins. • CrVI (0.1 ppm) increased oxidative stress during fetal ovarian development. • We propose fetal ovarian culture model for high

  19. Fha Interaction with Phosphothreonine of TssL Activates Type VI Secretion in Agrobacterium tumefaciens

    Science.gov (United States)

    Lin, Jer-Sheng; Wu, Hsin-Hui; Hsu, Pang-Hung; Ma, Lay-Sun; Pang, Yin-Yuin; Tsai, Ming-Daw; Lai, Erh-Min

    2014-01-01

    The type VI secretion system (T6SS) is a widespread protein secretion system found in many Gram-negative bacteria. T6SSs are highly regulated by various regulatory systems at multiple levels, including post-translational regulation via threonine (Thr) phosphorylation. The Ser/Thr protein kinase PpkA is responsible for this Thr phosphorylation regulation, and the forkhead-associated (FHA) domain-containing Fha-family protein is the sole T6SS phosphorylation substrate identified to date. Here we discovered that TssL, the T6SS inner-membrane core component, is phosphorylated and the phosphorylated TssL (p-TssL) activates type VI subassembly and secretion in a plant pathogenic bacterium, Agrobacterium tumefaciens. Combining genetic and biochemical approaches, we demonstrate that TssL is phosphorylated at Thr 14 in a PpkA-dependent manner. Further analysis revealed that the PpkA kinase activity is responsible for the Thr 14 phosphorylation, which is critical for the secretion of the T6SS hallmark protein Hcp and the putative toxin effector Atu4347. TssL phosphorylation is not required for the formation of the TssM-TssL inner-membrane complex but is critical for TssM conformational change and binding to Hcp and Atu4347. Importantly, Fha specifically interacts with phosphothreonine of TssL via its pThr-binding motif in vivo and in vitro and this interaction is crucial for TssL interaction with Hcp and Atu4347 and activation of type VI secretion. In contrast, pThr-binding ability of Fha is dispensable for TssM structural transition. In conclusion, we discover a novel Thr phosphorylation event, in which PpkA phosphorylates TssL to activate type VI secretion via its direct binding to Fha in A. tumefaciens. A model depicting an ordered TssL phosphorylation-induced T6SS assembly pathway is proposed. PMID:24626341

  20. A first-principles study of group IV and VI atoms doped blue phosphorene

    Science.gov (United States)

    Bai, Ruimin; Chen, Zheng; Gou, Manman; Zhang, Yixin

    2018-02-01

    Using first-principles calculations, we have systematically investigated the structural, electronic and magnetic properties of blue phosphorene doped by group IV and VI atoms, including C, Si, Ge, Sn, O, S, Se and Te. All the doped systems are energetically stable. Only C, Si, Ge and O-substituted systems show the characteristics of spin polarization and the magnetic moments are all 1.0 μB. Moreover, we found that C, Si, Ge and O doped systems are indirect bandgap semiconductors, while Sn, S, Se and Te doped systems present metallic property. These results show that blue phosphorene can be used prospectively in optoelectronic and spintronic devices.

  1. Survival of the children population with tumors of the central nervous system

    International Nuclear Information System (INIS)

    Brossard Alejo, Julio; Nunnez Ferrer, Pedro; Rodriguez Herrera, Ernesto; Agustin Antomarchi, Luis M; Romero Garcia, Lazaro

    2011-01-01

    A descriptive, longitudinal and retrospective study of all the patients with tumors of the central nervous system, admitted to the Southern Children Hospital in Santiago de Cuba, from 1987 to 2006, in order to analyze the survival of this population whose mean was 45-49 months ± 5,84. It was found that age, tissue aspects, anatomical site, and resection degree, as well as the applied treatments (radiotherapy and chemotherapy), constituted decisive factors to improve the life prognosis of the case material. (author)

  2. Sabanejewia Aurata (De Filippi, 1863 Populations Management Decisions Support System for Rosci0132 (Olt River Basin

    Directory of Open Access Journals (Sweden)

    Curtean-Bănăduc Angela

    2015-06-01

    Full Text Available The ADONIS: CE was used to design a specific management model for the Sabanejewia aurata (De Filippi, 1863 populations. The proposed model is based on this species, in situ identified biological/ecological necessities in relation to the habitats, the conservation status indicators and appropriate management actions and the pressures and threats founded in the study area. Such on species, on habitats and on site based management system was done to complete this approach for ROSCI0132, the other fish species which are living there being treated already in this respect.

  3. Glycogen Storage Disease Type VI With a Novel Mutation in PYGL Gene.

    Science.gov (United States)

    Jagadisan, Barath; Ranganath, Prajnya

    2017-09-15

    Glycogen storage disease type VI (GSD-VI) presents with failure to thrive and also fibrosis in some cases, without cirrhosis. 2½-year-old girl presented with short stature, transaminase elevation and significant fibrosis, suggesting GSD-III. A pathogenic mutation in PYGL gene suggested GSD-VI. GSD-VI should be a differential diagnosis whenever GSD-III is suspected.

  4. Recovery of uranium (VI) from low level aqueous radioactive waste

    International Nuclear Information System (INIS)

    Kulshrestha, Mukul

    1996-01-01

    Investigation was undertaken to evaluate the uranium (VI) removal and recovery potential of a naturally occurring, nonviable macrofungus, Ganoderma Lucidum from the simulated low level aqueous nuclear waste. These low level waste waters discharged from nuclear mine tailings and nuclear power reactors have a typical U(VI) concentration of 10-100 mg/L. It is possible to recover this uranium economically with the advent of biosorption as a viable technology. Extensive laboratory studies have revealed Ganoderma Lucidum to be a potential biosorbent with a specific uptake of 2.75 mg/g at an equilibrium U(VI) concentration of 10 mg/L at pH 4.5. To recover the sorbed U(VI), the studies indicated 0.2N Na 2 CO 3 to be an effective elutant. The kinetics of U(VI) desorption from loaded Ganoderma Lucidum with 0.2N Na 2 CO 3 as elutant, was found to be rapid with more than 75% recovery occurring in the first five minutes, the specific metal release rate being 0.102 mg/g/min. The equilibrium data fitted to a linearised Freundlich plot and exhibited a near 100% recovery of sorbed U(VI), clearly revealing a cost-effective method of recovery of precious uranium from low level wastewater. (author). 7 refs., 3 figs., 1 tab

  5. Lack of Collagen VI Promotes Wound-Induced Hair Growth.

    Science.gov (United States)

    Chen, Peiwen; Cescon, Matilde; Bonaldo, Paolo

    2015-10-01

    Collagen VI is an extracellular matrix molecule that is abundantly expressed in the skin. However, the role of collagen VI in hair follicle growth is unknown. Here, we show that collagen VI is strongly deposited in hair follicles, and is markedly upregulated by skin wounding. Lack of collagen VI in Col6a1(-/-) mice delays hair cycling and growth under physiological conditions, but promotes wound-induced hair regrowth without affecting skin regeneration. Conversely, addition of purified collagen VI rescues the abnormal wound-induced hair regrowth in Col6a1(-/-) mice. Mechanistic studies revealed that the increased wound-induced hair regrowth of Col6a1(-/-) mice is triggered by activation of the Wnt/β-catenin signaling pathway, and is abolished by inhibition of this pathway. These findings highlight the essential relationships between extracellular matrix (ECM) and hair follicle regeneration, and suggest that collagen VI could be a potential therapeutic target for hair loss and other skin-related diseases.

  6. Fe(III) photocatalytic reduction of Cr(VI) by low-molecular-weight organic acids with α-OH

    International Nuclear Information System (INIS)

    Sun Jun; Mao, J.-D.; Gong Hui; Lan Yeqing

    2009-01-01

    The photochemical reduction of Cr(VI) by four low-molecular-weight organic acids (tartaric acid, citric acid, malic acid, and n-butyric acid) in the presence of either dissolved Fe(III) in dilute aqueous solution or adsorbed Fe(III) on clay mineral surfaces (kaolinite, montmorillonite and illite) was investigated using batch reactors at a pH range from 3.5 to 4.5 at 25 deg. C. The results indicate that Fe(III) photocatalytic reduction of Cr(VI) by organic acids with α-OH is extremely fast. During a reaction period when less than 80% initial Cr(VI) was consumed, the reaction can be described as pseudo-first-order with respect to Cr(VI) when organic acid in excess. By plotting ln[Cr(VI)] as a function of reaction time, rate constants of Cr(VI) reduction by organic acids are obtained. The rate constants involving the four acids are in the order: tartaric acid (with 2 carboxylic groups and 2 α-OH groups) > citric acid (with 3 carboxylic groups and 1 α-OH group) ∼ malic acid (with 2 carboxylic groups and 1 α-OH group) >> n-butyric acid (with 1 carboxylic group and no α-OH group). This order suggests that the number of α-OH but not the number of carboxylic groups is an important determinant of kinetics. With light, the reduction of Cr(VI) by citric acid is accelerated by clay minerals. The enhancement of Cr(VI) reduction is attributed to the catalysis of Fe(III) adsorbed on clay mineral surfaces. However, such an acceleration is markedly suppressed by introducing NaF into the reaction system since NaF forms a complex with Fe(III). It is concluded that the complex formation between Fe(III) and organic acid is a key step for the photocatalytic reduction of Cr(VI) in the presence of Fe(III) and organic acids with α-OH.

  7. Interaction of uranium(VI) with bioligands present in human biological fluids. The case study of urea and uric acid

    Energy Technology Data Exchange (ETDEWEB)

    Osman, A.A.A.; Geipel, G.; Bernhard, G. [Helmholtz-Zentrum Dresden-Rossendorf, Dresden (Germany). Inst. of Resource Ecology

    2013-05-01

    The complexation of uranium(VI) with bioligands found in human biological fluids, viz, urea and uric acid in aqueous solutions, has been investigated using time-resolved laser-induced fluorescence spectroscopy (TRLFS) at room temperature, I = 0.1 M (NaClO4) and pH (3 for uric acid; 4 for urea). In both complex systems a static quench effect with increasing ligand concentration and no peaks shift upon complexation were observed. With uranium(VI) both ligands formed a fairly weak 1:1 complex with average stability constants of log {beta}{sub 110} = 4.67 {+-} 0.29 for uric acid and log {beta}{sub 110} = 3.79 {+-} 0.15 and 2.12 {+-} 0.18 for relatively low and relatively high urea concentrations, respectively. Application of the newly generated data on the U(VI) speciation modelling in biofluids, e.g., human urine was also discussed.

  8. Interaction of uranium(VI) with bioligands present in human biological fluids. The case study of urea and uric acid

    International Nuclear Information System (INIS)

    Osman, A.A.A.; Geipel, G.; Bernhard, G.

    2013-01-01

    The complexation of uranium(VI) with bioligands found in human biological fluids, viz, urea and uric acid in aqueous solutions, has been investigated using time-resolved laser-induced fluorescence spectroscopy (TRLFS) at room temperature, I = 0.1 M (NaClO4) and pH (3 for uric acid; 4 for urea). In both complex systems a static quench effect with increasing ligand concentration and no peaks shift upon complexation were observed. With uranium(VI) both ligands formed a fairly weak 1:1 complex with average stability constants of log β 110 = 4.67 ± 0.29 for uric acid and log β 110 = 3.79 ± 0.15 and 2.12 ± 0.18 for relatively low and relatively high urea concentrations, respectively. Application of the newly generated data on the U(VI) speciation modelling in biofluids, e.g., human urine was also discussed.

  9. [Penrose's law: reality or fiction? Mental health system and the size of prison population - international overview].

    Science.gov (United States)

    Kalapos, Miklós Péter

    2009-07-12

    According to the Penrose's law, outlined on the basis of a comparative study of European statistics, there is an inverse relationship between the number of psychiatric beds and prison population. Based on international data, interrelationship among prison, asylum, psychiatric disease and criminal action are investigated in the present study, paying particular attention to the event of deinstitutionalization. Prevalence of mental and addictive diseases as well as psychological disturbances in prison is characterized by epidemiological data. As proposed by Penrose, an inverse relationship between the number of psychiatric beds and prison population can be observed in Hungary, too. To get a deeper insight into the mainstream of the events, economic, sociological, philosophical, as well as therapeutic aspects initializing deinstitutionalization are highlighted in the course of analysis. On the basis of data, it can be assumed that members the same population are confined to both systems. The author arrives at the conclusion that deinstitutionalization has in fact led to trans-institutionalization, because of, on one hand, the limited capacity of community treatment facilities; on the other hand, the community treatment itself cannot provide adequate treatment options to those suffering from severe, chronic mental diseases or comorbid states. In addition, the rate of financial support and the methods for prevention and treatment are insufficient to protect patients from the effects of revolving door.

  10. Association of TNFAIP3 Polymorphism with Susceptibility to Systemic Lupus Erythematosus in a Japanese Population

    Directory of Open Access Journals (Sweden)

    Aya Kawasaki

    2010-01-01

    Full Text Available Recent genome-wide association studies demonstrated association of single nucleotide polymorphisms (SNPs in the TNFAIP3 region at 6q23 with systemic lupus erythematosus (SLE in European-American populations. In this study, we investigated whether SNPs in the TNFAIP3 region are associated with SLE also in a Japanese population. A case-control association study was performed on the SNPs rs13192841, rs2230926, and rs6922466 in 318 Japanese SLE patients and 444 healthy controls. Association of rs2230926 G allele with SLE was replicated in Japanese (allelic association P=.033, odds ratio [OR] 1.47, recessive model P=.023, OR 8.52. The association was preferentially observed in the SLE patients with nephritis. When the TNFAIP3 mRNA levels of the HapMap samples were examined using GENEVAR database, the presence of TNFAIP3 rs2230926 G allele was associated with lower mRNA expression of TNFAIP3 (P=.013. These results indicated that TNFAIP3 is a susceptibility gene to SLE both in the Caucasian and Asian populations.

  11. 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...

  12. Revealing the role of predator interference in a predator-prey system with disease in prey population

    DEFF Research Database (Denmark)

    Chakraborty, Subhendu; Kooi, B.W.; Biswas, B.

    2015-01-01

    Predation on a species subjected to an infectious disease can affect both the infection level and the population dynamics. There is an ongoing debate about the act of managing disease in natural populations through predation. Recent theoretical and empirical evidence shows that predation...... on infected populations can have both positive and negative influences on disease in prey populations. Here, we present a predator-prey system where the prey population is subjected to an infectious disease to explore the impact of predator on disease dynamics. Specifically, we investigate how...... on the strength of interference among predators, predators enhance or control disease outbreaks and population persistence. Moreover, the presence of multistable regimes makes the system very sensitive to perturbations and facilitates a number of regime shifts. Since, the habitat structure and the choice...

  13. Magnetic chitosan for removal of uranium (VI)

    International Nuclear Information System (INIS)

    Stopa, Luiz Claudio Barbosa

    2007-01-01

    The chitosan, an aminopolysaccharide formed for repeated units of D-glucosamine, is a deacetylation product of chitin. It presents favorable ionic properties acting as chelant, being considered a removing ionic of contaminants from water effluents. It has ample bioactivity, that is, is biocompatible, biodegradable, bioadhesive and biosorbent. The chitosan interacts for crosslinked by means of its active groups with other substances, can still coat superparamagnetic materials as magnetite nanoparticles producing one conjugated polymer-magnetite. Superparamagnetic materials are susceptible for the magnetic field, thus these particles can be attracted and grouped by a magnetic field and as they do not hold back the magnetization, they can be disagrouped and reused in processes for removal of contaminants from industrial effluents and waste water. The present work consisted of preparing coated magnetic magnetite particles with chitosan (PMQ). The PMQ powder has showed a magnetic response of intense attraction in the presence of a magnetic field without however becoming magnetic, a typical behavior of superparamagnetic material. It was characterized by Fourier transform infrared spectrometry and measurements of magnetization. Its performance of Uranium (VI) adsorption as uranyl species, U0 2 2+ , was evaluated with regard to the influence of adsorbent dose, speed of agitation, pH, the contact time and had studied the isotherms of adsorption as well as the behavior of desorption using ions of carbonate and oxalate. The optimal pH to the best removal occurred in pH 5 and that the increase of the dose increases the removal, becoming constant above of 20 g.L -1 . In the kinetic study the equilibrium was achieved after 20 minutes. The results of equilibrium isotherm agreed well with the Langmuir model, being the maximum adsorption capacity equal 41.7 mg.g -1 . In the desorption studies were verified 94% of U0 2 2+ recovered with carbonate ion and 49.9% with oxalate ion

  14. The diversity of planetary system from formation/composition population synthesis models

    Science.gov (United States)

    Alibert, Yann; thiabaud, amaury; marboeuf, ulysses; swoboda, david; benz, willy; mezger, klaus; leya, ingo

    2015-12-01

    Extrasolar planetary systems show an extreme diversity in mass and orbital architecture. Explaining this diversity is one of the key challenges for theoretical models and requires understanding the formation, composition and evolution of planetary systems from the stage of the protoplanetary disk up to the full mature planetary system. Such an effort needs the development of end-to-end, necessarily simplified, formation models used in a population synthesis approach. We present in this contribution such planetary system formation and composition models. Our planetary system formation models include the following effects: planetary growth by capture of solids and gas, protoplanetary disk structure and evolution, planet-planet and planet-disk interactions. In addition, we compute the composition of the solids and gas in the protoplanetary disk and their evolution with time. The formation and composition models allow therefore the determination of the composition of planets in terms of refractory elements (Mg, Si, Fe, etc…) as well as volatile compounds (water, CO2, CO, NH3, etc…), in a way that is self-consistent with the formation process of the different members of the planetary system. We will show the results of these formation/composition models, and will compare the diversity of observed and synthetic planetary systems. Considering the solar system, we will show how different formation scenarios translate into different planetary compositions. Finally, we will demonstrate how the simultaneous determination of mass and radius of a statistical number of warm to cold earth to neptune mass bodies at different ages can be used to constrain the composition (in particular the volatile content) of planets, and how the same observations (mass, radius, period) can be used in order to select planets that are best suited for follow-up habitability studies.

  15. Voltammetric study of chromium(VI)-ammonia/ammonium chloride solutions in the presence of dimethylglyoxime

    Energy Technology Data Exchange (ETDEWEB)

    Ginzburg, V.G.; Salikhdzhanova, R.M.F.

    1987-10-10

    The authors believed complexation to be possible in the system Cr(VI)-dimethylglyoxime (DMG, H/sub 2/D) by reduction of Cr(VI) to Cr(III) on a mercury electrode. The DMG can be used in chromium voltammetry and is promising for a number of reasons: The Cr(III) has an affinity for donor nitrogen atoms in the DMG molecule. Insertion of the H/sub 2/D into the inner sphere of the complex is expected to weaken the bond between the Cr(III) and the hydroxyl group, slow down formation of the insoluble hydroxide Cr(OH)/sub 3/, and lower the rate of the electrode reaction Cr(III) ..-->.. Cr(II). Molecules of H/sub 2/D adsorb on a mercury electrode. It is therefore possible to accelerate the electrode process by including adsorptive preconcentration of the chromium and thus lowering its detection limit. This paper reports the voltammetric behavior of the system Cr(VI)-DMG-NH/sub 4//sup +/ (proton donor) for the purpose of lowering the chromium detection limit.

  16. Removal of Cr (VI) from aqueous solutions using peanut shell as adsorbent

    International Nuclear Information System (INIS)

    Ilyas, M.; Ahmad, A.; Saeed, M.

    2013-01-01

    The biosorption of Cr (VI) ions from aqueous solution by peanut shell (PNS) biosorbent was studied in a batch mode system. Factors affecting Cr (VI) biosorption such as pH (2-7), initial chromium ion concentrations (20-60 mg/l), contact time (6 h), adsorbent dosage (0.2-1.0 g) and temperature (293-313 K) were investigated. The adsorption equilibrium was established at 360 minutes. A comparison of the kinetic models has showed that pseudo-second order equation best described adsorption kinetics. Maximum adsorption was achieved at pH 2.0 and 3.0. The adsorption equilibrium data was fitted well to the Langmuir adsorption isotherm as compared to the Freundlich adsorption isotherm. The values of separation factor, R/sub L/ was found between 0.0235 and 0.0633 (0 < R/sub L/ < 1) which pointed out favorable adsorption of Cr (VI) on PNS adsorbent. The adsorption capacity was measured in terms of monolayer adsorption and was found to be 4.32 mg/g at 313 K. The thermodynamic parameters (ΔG, ΔH and ΔS) values indicated the endothermic, non spontaneous and entropy driven system of the adsorption process. (author)

  17. [Current aspects of the Russian Federation population's mortality from diseases of the respiratory system].

    Science.gov (United States)

    Kakorkina, E P; Efimov, D M; Chemiakina, S-D N

    2010-01-01

    Diseases of the respiratory system are in the lead of general mortality of population, they tend to increase, particularly with regard to pneumonias, chronic obstructive pulmonary diseases, bronchial asthma and others. The paper surveys the structure and levels of mortality from diseases of the respiratory system, sex and age indices with special reference to the working age, the mortality dynamics since 2000, levels of mortality by regions with special reference to subjects with the minimum and maximum levels both for the total and by the main nosologies (pneumonia, diseases of the lower respiratory tract, bronchial asthma); an attempt is made to carry out the correlation analysis of the level of mortality from diseases by the main nosologies.

  18. Defective collagen VI ?6 chain expression in the skeletal muscle of patients with collagen VI-related myopathies

    OpenAIRE

    Tagliavini, F.; Pellegrini, C.; Sardone, F.; Squarzoni, S.; Paulsson, M.; Wagener, R.; Gualandi, F.; Trabanelli, C.; Ferlini, A.; Merlini, L.; Santi, S.; Maraldi, N.M.; Faldini, C.; Sabatelli, P.

    2014-01-01

    Collagen VI is a non-fibrillar collagen present in the extracellular matrix (ECM) as a complex polymer; the mainly expressed form is composed of ?1, ?2 and ?3 chains; mutations in genes encoding these chains cause myopathies known as Ullrich congenital muscular dystrophy (UCMD), Bethlem myopathy (BM) and myosclerosis myopathy (MM). The collagen VI ?6 chain is a recently identified component of the ECM of the human skeletal muscle. Here we report that the ?6 chain was dramatically reduced in s...

  19. Applying operations research to optimize a novel population management system for cancer screening.

    Science.gov (United States)

    Zai, Adrian H; Kim, Seokjin; Kamis, Arnold; Hung, Ken; Ronquillo, Jeremiah G; Chueh, Henry C; Atlas, Steven J

    2014-02-01

    To optimize a new visit-independent, population-based cancer screening system (TopCare) by using operations research techniques to simulate changes in patient outreach staffing levels (delegates, navigators), modifications to user workflow within the information technology (IT) system, and changes in cancer screening recommendations. TopCare was modeled as a multiserver, multiphase queueing system. Simulation experiments implemented the queueing network model following a next-event time-advance mechanism, in which systematic adjustments were made to staffing levels, IT workflow settings, and cancer screening frequency in order to assess their impact on overdue screenings per patient. TopCare reduced the average number of overdue screenings per patient from 1.17 at inception to 0.86 during simulation to 0.23 at steady state. Increases in the workforce improved the effectiveness of TopCare. In particular, increasing the delegate or navigator staff level by one person improved screening completion rates by 1.3% or 12.2%, respectively. In contrast, changes in the amount of time a patient entry stays on delegate and navigator lists had little impact on overdue screenings. Finally, lengthening the screening interval increased efficiency within TopCare by decreasing overdue screenings at the patient level, resulting in a smaller number of overdue patients needing delegates for screening and a higher fraction of screenings completed by delegates. Simulating the impact of changes in staffing, system parameters, and clinical inputs on the effectiveness and efficiency of care can inform the allocation of limited resources in population management.

  20. Nonlinearities lead to qualitative differences in population dynamics of predator-prey systems.

    Directory of Open Access Journals (Sweden)

    Olga M C C Ameixa

    Full Text Available Since typically there are many predators feeding on most herbivores in natural communities, understanding multiple predator effects is critical for both community and applied ecology. Experiments of multiple predator effects on prey populations are extremely demanding, as the number of treatments and the amount of labour associated with these experiments increases exponentially with the number of species in question. Therefore, researchers tend to vary only presence/absence of the species and use only one (supposedly realistic combination of their numbers in experiments. However, nonlinearities in density dependence, functional responses, interactions between natural enemies etc. are typical for such systems, and nonlinear models of population dynamics generally predict qualitatively different results, if initial absolute densities of the species studied differ, even if their relative densities are maintained. Therefore, testing combinations of natural enemies without varying their densities may not be sufficient. Here we test this prediction experimentally. We show that the population dynamics of a system consisting of 2 natural enemies (aphid predator Adalia bipunctata (L., and aphid parasitoid, Aphidius colemani Viereck and their shared prey (peach aphid, Myzus persicae Sulzer are strongly affected by the absolute initial densities of the species in question. Even if their relative densities are kept constant, the natural enemy species or combination thereof that most effectively suppresses the prey may depend on the absolute initial densities used in the experiment. Future empirical studies of multiple predator - one prey interactions should therefore use a two-dimensional array of initial densities of the studied species. Varying only combinations of natural enemies without varying their densities is not sufficient and can lead to misleading results.

  1. Utility rate equations of group population dynamics in biological and social systems.

    Science.gov (United States)

    Yukalov, Vyacheslav I; Yukalova, Elizaveta P; Sornette, Didier

    2013-01-01

    We present a novel system of equations to describe the evolution of self-organized structured societies (biological or human) composed of several trait groups. The suggested approach is based on the combination of ideas employed in the theory of biological populations, system theory, and utility theory. The evolution equations are defined as utility rate equations, whose parameters are characterized by the utility of each group with respect to the society as a whole and by the mutual utilities of groups with respect to each other. We analyze in detail the cases of two groups (cooperators and defectors) and of three groups (cooperators, defectors, and regulators) and find that, in a self-organized society, neither defectors nor regulators can overpass the maximal fractions of about [Formula: see text] each. This is in agreement with the data for bee and ant colonies. The classification of societies by their distance from equilibrium is proposed. We apply the formalism to rank the countries according to the introduced metric quantifying their relative stability, which depends on the cost of defectors and regulators as well as their respective population fractions. We find a remarkable concordance with more standard economic ranking based, for instance, on GDP per capita.

  2. Selection and genetic gain in rubber tree (Hevea populations using a mixed mating system

    Directory of Open Access Journals (Sweden)

    Costa Reginaldo Brito da

    2000-01-01

    Full Text Available The components of genetic variation and genetic gain obtained with three selection methods - individual, combined and multi-effect index selection - were compared in rubber tree [Hevea brasiliensis (Willd. ex Adr. de Juss. Muell. Arg.] progenies. The rubber tree is a cross pollinating species with a mixed reproductive system in which the self pollination rate is 22%. Twenty-two half sib progenies were planted at experimental stations at Pindorama, Votuporanga and Jaú, in São Paulo State, using a randomized and complete block design, with five replications and ten plants per plot. Dry rubber production was assessed when the plants were three years old. Based on the genetic variability of the populations, Pindorama was the best environment for the expression of variability. At the individual level, heritability was seriously affected when random progenies from an open pollinating population were considered as half sib progenies. Considerable overestimation of genetic gains occurred during individual, combined and multi-effect index selection when the rubber tree reproductive system was not considered as mixed. Selection based on the multi-effect index maximizes genetic progress and should be used more in rubber tree breeding programs.

  3. Scaling Effects of Cr(VI) Reduction Kinetics. The Role of Geochemical Heterogeneity

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Li [Pennsylvania State Univ., State College, PA (United States); Li, Li [Pennsylvania State Univ., State College, PA (United States)

    2015-10-22

    The natural subsurface is highly heterogeneous with minerals distributed in different spatial patterns. Fundamental understanding of how mineral spatial distribution patterns regulate sorption process is important for predicting the transport and fate of chemicals. Existing studies about the sorption was carried out in well-mixed batch reactors or uniformly packed columns, with few data available on the effects of spatial heterogeneities. As a result, there is a lack of data and understanding on how spatial heterogeneities control sorption processes. In this project, we aim to understand and develop modeling capabilities to predict the sorption of Cr(VI), an omnipresent contaminant in natural systems due to its natural occurrence and industrial utilization. We systematically examine the role of spatial patterns of illite, a common clay, in determining the extent of transport limitation and scaling effects associated with Cr(VI) sorption capacity and kinetics using column experiments and reactive transport modeling. Our results showed that the sorbed mass and rates can differ by an order of magnitude due to of the illite spatial heterogeneities and transport limitation. With constraints from data, we also developed the capabilities of modeling Cr(VI) in heterogeneous media. The developed model is then utilized to understand the general principles that govern the relationship between sorption and connectivity, a key measure of the spatial pattern characteristics. This correlation can be used to estimate Cr(VI) sorption characteristics in heterogeneous porous media. Insights gained here bridge gaps between laboratory and field application in hydrogeology and geochemical field, and advance predictive understanding of reactive transport processes in the natural heterogeneous subsurface. We believe that these findings will be of interest to a large number of environmental geochemists and engineers, hydrogeologists, and those interested in contaminant fate and transport

  4. Genetic analysis of eight population groups living in Taiwan using a 13 X-chromosomal STR loci multiplex system.

    Science.gov (United States)

    Hwa, Hsiao-Lin; Lee, James Chun-I; Chang, Yih-Yuan; Yin, Hsiang-Yi; Chen, Ya-Hui; Tseng, Li-Hui; Su, Yi-Ning; Ko, Tsang-Ming

    2011-01-01

    A 13 X-chromosomal short tandem repeat (STR) multiplex system (DXS6807, DXS8378, DSX9902, DXS7132, DXS9898, DXS6809, DXS6789, DXS7424, DXS101, GATA172D05, HPRTB, DXS8377, and DXS7423) was tested on 1,037 DNA samples from eight population groups currently living in Taiwan. Different distributions of the allelic frequencies in different populations were presented. DXS8377 and DXS101 were the two most polymorphic loci in these eight populations, whereas DXS7423 was the least informative marker in most of the populations studied. The genetic distances between the populations and the constructed phylogenetic tree revealed a long genetic distance between Asian and Caucasian populations as well as isolation of the Tao population. The phylogenetic tree grouped populations into clusters compatible with their ethnogeographic relationships. This 13 X-chromosomal short tandem repeat multiplex system offers a considerable number of polymorphic patterns in different populations. This system can be useful in forensic identification casework and ethnogeographic research.

  5. Organophosphinic, phosphonic acids and their binary mixtures as extractants for molybdenum(VI) and uranium(VI) from aqueous HCl media

    International Nuclear Information System (INIS)

    Behera, P.; Mishra, S.; Mohanty, I.; Chakravortty, V.

    1994-01-01

    Extraction studies of uranium(VI) and molybdenum(VI) with organophosphoric, phosphinic acid and its thiosubstituted derivatives have been carried out from 0.1-1.0M HCl solutions. The extracted species are proposed to be UO 2 R 2 and MoO 2 CIR on the basis of slope analysis for uranium(VI) and molybdenum(VI), respectively. The extraction efficiencies of PC-88A, Cyanex 272, Cyanex 301 and Cyanex 302 in the extraction of molybdenum(VI) and uranium(VI) are compared. Synergistic effects have been studied with binary mixtures of extractants. Separation of molybdenum(VI) from uranium(VI) is feasible by Cyanex 301 from 1M HCl, the separation factor logβ being 2.3. (author) 20 refs.; 5 figs.; 14 tabs

  6. Single-molecule studies of unconventional motor protein myosin VI

    Science.gov (United States)

    Kim, HyeongJun

    Myosin VI is one of the myosin superfamily members that are actin-based molecular motors. It has received special attention due to its distinct features as compared to other myosins, such as its opposite directionality and a much larger step size than expected given the length of its "leg". This dissertation presents the author.s graduate work of several single-molecule studies on myosin VI. Special attention was paid to some of myosin VI.s tail domains that consist of proximal tail (PT), medial tail (MT), distal tail (DT) domains and cargo-binding domain (CBD). The functional form of myosin VI in cells is still under debate. Although full length myosin VI proteins in cytosolic extracts of cells were monomers from earlier studies, there are several reasons why it is now believed that myosin VI could exist as a dimer. If this is true and dimerization occurs, the next logical question would be which parts of myosin VI are dimerization regions? One model claimed that the CBD is the sole dimerization region. A competing model claimed that there must be another region that could be involved in dimerization, based on their observation that a construct without the CBD could still dimerize. Our single-molecule experiment with progressively truncated myosin VI constructs showed that the MT domain is a dimerization region, supporting the latter model. Additional single-molecule experiments and molecular dynamics (MD) simulation done with our collaborators suggest that electrostatic salt bridges formed between positive and negative amino acid residues are mainly responsible for the MT domain dimerization. After resolving this, we are left with another important question which is how myosin VI can take such a large step. Recent crystal structure showed that one of the tail domains preceding the MT domain, called the PT domain, is a three-helix bundle. The most easily conceivable way might be an unfolding of the three-helix bundle upon dimerization, allowing the protein to

  7. Forging a Frailty-Ready Healthcare System to Meet Population Ageing

    Directory of Open Access Journals (Sweden)

    Wee Shiong Lim

    2017-11-01

    Full Text Available The beginning of the 21st century has seen health systems worldwide struggling to deliver quality healthcare amidst challenges posed by ageing populations. The increasing prevalence of frailty with older age and accompanying complexities in physical, cognitive, social and psychological dimensions renders the present modus operandi of fragmented, facility-centric, doctor-based, and illness-centered care delivery as clearly unsustainable. In line with the public health framework for action in the World Health Organization’s World Health and Ageing Report, meeting these challenges will require a systemic reform of healthcare delivery that is integrated, patient-centric, team-based, and health-centered. These reforms can be achieved through building partnerships and relationships that engage, empower, and activate patients and their support systems. To meet the challenges of population ageing, Singapore has reorganised its public healthcare into regional healthcare systems (RHSs aimed at improving population health and the experience of care, and reducing costs. This paper will describe initiatives within the RHS frameworks of the National Health Group (NHG and the Alexandra Health System (AHS to forge a frailty-ready healthcare system across the spectrum, which includes the well healthy (“living well”, the well unhealthy (“living with illness”, the unwell unhealthy (“living with frailty”, and the end-of-life (EoL (“dying well”. For instance, the AHS has adopted a community-centered population health management strategy in older housing estates such as Yishun to build a geographically-based care ecosystem to support the self-management of chronic disease through projects such as “wellness kampungs” and “share-a-pot”. A joint initiative by the Lien Foundation and Khoo Teck Puat Hospital aims to launch dementia-friendly communities across the island by building a network comprising community partners, businesses, and members

  8. Established Microbial Colonies Can Survive Type VI Secretion Assault.

    Directory of Open Access Journals (Sweden)

    David Bruce Borenstein

    2015-10-01

    Full Text Available Type VI secretion (T6S is a cell-to-cell injection system that can be used as a microbial weapon. T6S kills vulnerable cells, and is present in close to 25% of sequenced Gram-negative bacteria. To examine the ecological role of T6S among bacteria, we competed self-immune T6S+ cells and T6S-sensitive cells in simulated range expansions. As killing takes place only at the interface between sensitive and T6S+ strains, while growth takes place everywhere, sufficiently large domains of sensitive cells can achieve net growth in the face of attack. Indeed T6S-sensitive cells can often outgrow their T6S+ competitors. We validated these findings through in vivo competition experiments between T6S+ Vibrio cholerae and T6S-sensitive Escherichia coli. We found that E. coli can survive and even dominate so long as they have an adequate opportunity to form microcolonies at the outset of the competition. Finally, in simulated competitions between two equivalent and mutually sensitive T6S+ strains, the more numerous strain has an advantage that increases with the T6S attack rate. We conclude that sufficiently large domains of T6S-sensitive individuals can survive attack and potentially outcompete self-immune T6S+ bacteria.

  9. Population-based learning of load balancing policies for a distributed computer system

    Science.gov (United States)

    Mehra, Pankaj; Wah, Benjamin W.

    1993-01-01

    Effective load-balancing policies use dynamic resource information to schedule tasks in a distributed computer system. We present a novel method for automatically learning such policies. At each site in our system, we use a comparator neural network to predict the relative speedup of an incoming task using only the resource-utilization patterns obtained prior to the task's arrival. Outputs of these comparator networks are broadcast periodically over the distributed system, and the resource schedulers at each site use these values to determine the best site for executing an incoming task. The delays incurred in propagating workload information and tasks from one site to another, as well as the dynamic and unpredictable nature of workloads in multiprogrammed multiprocessors, may cause the workload pattern at the time of execution to differ from patterns prevailing at the times of load-index computation and decision making. Our load-balancing policy accommodates this uncertainty by using certain tunable parameters. We present a population-based machine-learning algorithm that adjusts these parameters in order to achieve high average speedups with respect to local execution. Our results show that our load-balancing policy, when combined with the comparator neural network for workload characterization, is effective in exploiting idle resources in a distributed computer system.

  10. Incidence Rate of Concomitant Systemic Diseases in the Aging Population with Postmenopausal Osteoporosis

    Directory of Open Access Journals (Sweden)

    Selçuk Sayılır

    2016-08-01

    Full Text Available Objective: To evaluate the concomitant systemic diseases with postmenopausal osteoporosis and to investigate the points to be considered in treatment approach of patients with osteoporosis. Materials and Methods: The study included 110 female patients admitted to our clinic and followed up after postmenopausal osteoporosis diagnosis. Besides the demographic data; the concomitant diseases of the patients such as hypertension, hypo-hyperthyroidism, diabetes mellitus, Alzheimer’s disease, malignancy, osteoarthritis, gastrointestinal system diseases, chronic obstructive pulmonary disease (COPD- asthma and depression were also recorded. Results: The mean age of the patients included in our study was 65.9±9.8 years. When the concomitant systemic diseases were examined; 40 patients had hypertension, 32 patients had osteoarthritis, 24 patients had gastrointestinal tract problems, 22 patients had thyroid disease, 21 patients had depression, 15 patients had hyperlipidemia, 12 patients had diabetes mellitus, 10 patients had COPD - asthma, 7 patients had cardiac diseases, 5 patients had malignancy and 2 patients had Alzheimer disease. Conclusion: Osteoporosis is a common disease in the geriatric population. As a chronic disease with an increasing incidence with aging; it can cause many health problems, prevalently pathological bone fractures, in our country and all over the world. Constitutively, prophylaxis of osteoporosis should be the first step. Because systemic diseases with increasing incidence with aging may affect the severity of osteoporosis and impair the treatment; it is important for both clinicians and the society to have sufficient information about osteoporosis.

  11. 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.

  12. 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..

  13. Theoretical investigation of the II-VI and IV-VI families of diluted magnetic semiconductors

    Science.gov (United States)

    McNorton, Rhett D.

    This dissertation examines the electronic structure and magnetic properties of II-VI and IV-VI dilute magnetic semiconductors (DMS). Properties that are investigated include the exchange energy, magnetic moment, density of states, sources of the magnetic coupling, and the effect that crystal disorder has on the aforementioned parameters. The computational methods employed are the Vienna ab-initio Simulation Package (VASP), and the Layered Korringa-Kohn-Rostoker (LKKR) method. These two methods are based upon density functional theory. VASP relies on the construction of a pseudopotential and a plane wave expansion to model the charge density and wavefunction. LKKR uses multiple scattering theory to find the Green's function and electronic structure. The coherent potential approximation (CPA) can be readily incorporated into the LKKR approach, resulting in a first principle technique that can study a substitutionally disordered random alloy. We have studied how the double-exchange, super-exchange, and inter-band exchange are effected by the crystal symmetry of the host, the electronic structure of the transition metal, and geometry of the impurities d-shell. We observed in a few materials that a competition between exchange mechanism is possible. When the sign of the interactions are the same, the result is an unambiguous magnetic ground state. However, when the sign of the competing exchange mechanisms are opposite, the material is expected to have a weaker, often oscillating, magnetic coupling, as a result of magnetic frustration and sensitivity to transition metal spacing and orientation. We have also examined how the chemical interactions may be coupled to the magnetic interactions. This becomes important at high impurity concentrations when the transition metal impurity cannot participate effectively in crystal bonding. In these cases, the transition metal d-orbitals that reside in the gap, and are involved in the exchange, are forced to initiate bonding with

  14. Recovery of Cr as Cr(III) from Cr(VI)-contaminated kaolinite clay by electrokinetics coupled with a permeable reactive barrier.

    Science.gov (United States)

    Suzuki, Tasuma; Kawai, Katsunori; Moribe, Mai; Niinae, Masakazu

    2014-08-15

    Zero-valent iron (Fe(0)) and magnetite (Fe3O4) were investigated as potential reductants in an electrokinetic/permeable reactive barrier hybrid system (EK/PRB) for the recovery of Cr as Cr(III) from Cr(VI)-contaminated kaolinite. For the EK/Fe(0) PRB, regardless of the pH in the anode well, the system facilitated the reduction of Cr(VI) into Cr(III), but the recovery of the Cr(III) in the PRB was low. Conversely, the reduction of Cr(VI) occurred only in the PRB for the EK/Fe3O4 PRB. However, when the anode pH was not controlled and the soil pH values correspondingly decreased gradually from the anode side, a greater fraction of Cr(VI) sorbed onto the kaolinite; as a result, a lower amount of Cr(VI) migrated to the Fe3O4 PRB. In addition, it was found that the majority of Cr(VI) migrating to the Fe3O4 PRB retained its oxidation state without being converted into Cr(III). These two adverse effects were mitigated by maintaining the soil pH values at 6.8, but at the same time, 18% of Cr(VI) penetrated through the Fe3O4 PRB. The penetration of Cr(VI) through the Fe3O4 PRB was successfully prevented by increasing the reaction time through the introduction of a cation exchange membrane between the Fe3O4 PRB and the anode well. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Thermodynamics of (ketone + amine) mixtures. Part VI. Volumetric and speed of sound data at (293.15, 298.15, and 303.15) K for (2-heptanone + dipropylamine, +dibutylamine, or +triethylamine) systems

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Juan Antonio, E-mail: jagl@termo.uva.es [G.E.T.E.F., Departamento de Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, 47071 Valladolid (Spain); Alonso, Ivan; Mozo, Ismael; Garcia de la Fuente, Isaias; Cobos, Jose Carlos [G.E.T.E.F., Departamento de Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, 47071 Valladolid (Spain)

    2011-10-15

    Highlights: > V{sub m}{sup E}, u{sup E}, {kappa}{sub S}{sup E}, and {alpha}{sub p}{sup E} data for (2-heptanone + DPA, +DBA, or +TEA) systems have been determined. > Structural effects increase with the ketone size in systems with a given amine. > They are dominant for (2-heptanone + DPA, or +TEA) solutions. > Interactions between unlike molecules are more easily created in solutions with the shorter amines. > The application of the PFP theory and the internal pressure concept confirm these trends. - Abstract: Densities, {rho}, and speeds of sound, u, of {l_brace}2-heptanone + dipropylamine (DPA), +dibutylamine (DBA), or +triethylamine (TEA){r_brace} systems have been measured at (293.15, 298.15, and 303.15) K and atmospheric pressure using a vibrating tube densimeter and sound analyzer Anton Paar model DSA-5000. The {rho} and u values were used to calculate excess molar volumes, V{sub m}{sup E}, and the excess functions at 298.15 K for the speed of sound, u{sup E}, the thermal expansion coefficient, {alpha}{sub P}{sup E}, and for the isentropic compressibility, {kappa}{sub S}{sup E}. Structural effects increase with the ketone size in mixtures with a fixed amine. V{sub m}{sup E}, {kappa}{sub S}{sup E}, and {alpha}{sub P}{sup E} increase when DPA is replaced by DBA in systems with a given ketone as: (i) interactions between unlike molecules are more easily created in solutions containing the shorter amines; (ii) this effect predominates over that related to the disruption of the amine-amine interactions. Contributions to V{sub m}{sup E} from the creation of interactions between unlike molecules and from the breaking of the amine-amine interactions are both lower in absolute value for TEA systems when are compared to those of DPA solutions. The increasing positive V{sub m}{sup E} values observed when DPA is replaced by TEA in solutions with propanone or 2-butanone reveal that the former contribution is less relevant, and more important for the DPA mixtures. The

  16. An Updating System for the Gridded Population Database of China Based on Remote Sensing, GIS and Spatial Database Technologies

    Science.gov (United States)

    Yang, Xiaohuan; Huang, Yaohuan; Dong, Pinliang; Jiang, Dong; Liu, Honghui

    2009-01-01

    The spatial distribution of population is closely related to land use and land cover (LULC) patterns on both regional and global scales. Population can be redistributed onto geo-referenced square grids according to this relation. In the past decades, various approaches to monitoring LULC using remote sensing and Geographic Information Systems (GIS) have been developed, which makes it possible for efficient updating of geo-referenced population data. A Spatial Population Updating System (SPUS) is developed for updating the gridded population database of China based on remote sensing, GIS and spatial database technologies, with a spatial resolution of 1 km by 1 km. The SPUS can process standard Moderate Resolution Imaging Spectroradiometer (MODIS L1B) data integrated with a Pattern Decomposition Method (PDM) and an LULC-Conversion Model to obtain patterns of land use and land cover, and provide input parameters for a Population Spatialization Model (PSM). The PSM embedded in SPUS is used for generating 1 km by 1 km gridded population data in each population distribution region based on natural and socio-economic variables. Validation results from finer township-level census data of Yishui County suggest that the gridded population database produced by the SPUS is reliable. PMID:22399959

  17. An Updating System for the Gridded Population Database of China Based on Remote Sensing, GIS and Spatial Database Technologies

    Directory of Open Access Journals (Sweden)

    Xiaohuan Yang

    2009-02-01

    Full Text Available The spatial distribution of population is closely related to land use and land cover (LULC patterns on both regional and global scales. Population can be redistributed onto geo-referenced square grids according to this relation. In the past decades, various approaches to monitoring LULC using remote sensing and Geographic Information Systems (GIS have been developed, which makes it possible for efficient updating of geo-referenced population data. A Spatial Population Updating System (SPUS is developed for updating the gridded population database of China based on remote sensing, GIS and spatial database technologies, with a spatial resolution of 1 km by 1 km. The SPUS can process standard Moderate Resolution Imaging Spectroradiometer (MODIS L1B data integrated with a Pattern Decomposition Method (PDM and an LULC-Conversion Model to obtain patterns of land use and land cover, and provide input parameters for a Population Spatialization Model (PSM. The PSM embedded in SPUS is used for generating 1 km by 1 km gridded population data in each population distribution region based on natural and socio-economic variables. Validation results from finer township-level census data of Yishui County suggest that the gridded population database produced by the SPUS is reliable.

  18. Redox transformation and reductive immobilization of Cr(VI) in the Columbia River hyporheic zone sediments

    Science.gov (United States)

    Xu, Fen; Liu, Yuanyuan; Zachara, John; Bowden, Mark; Kennedy, David; Plymale, Andrew E.; Liu, Chongxuan

    2017-12-01

    An experimental and modeling study was conducted to investigate the redox transformation and reductive immobilization of groundwater contaminant Cr in hyporheic zone (HZ) sediments from U.S. DOE's Hanford Site, where groundwater Cr(VI) is migrating and discharging to the nearby Columbia River. Experimental results revealed that Cr(VI) can be reduced and immobilized by the HZ sediments in the presence/absence of O2. Anaerobic pre-incubation of the sediments increased the effective rate of Cr reduction that was correlated with the increase in HCl-extractable Fe(II) content in the sediments. The reduced Cr was stable when exposed to O2 under field-relevant pH (7.5) with and without dissolved Mn(II), which might be oxidized to form Mn(III/IV) oxides that may oxidize reduced Cr. The Cr(VI) reduction rate showed a multi-rate behavior, apparently reflecting the presence of reductants with different reactivity in the sediments. The results from this study indicated that the HZ sediments can reductively immobilize Cr and the sediment redox capacity can be recharged through microbial activities. The results implied that HZ can play a role as a natural permeable redox barrier for removing groundwater Cr before it discharges into a river system.

  19. Redox transformation and reductive immobilization of Cr(VI) in the Columbia River hyporheic zone sediments

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Fen; Liu, Yuanyuan; Zachara, John M.; Bowden, Mark E.; Kennedy, David W.; Plymale, Andrew E.; Liu, Chongxuan,

    2017-12-01

    An experimental and modeling study was conducted to investigate the redox transformation and reductive immobilization of groundwater contaminant Cr in hyporheic zone (HZ) sediments from U.S. Department of Energy’s Hanford site, where groundwater Cr(VI) is migrating and discharging to the nearby Columbia River. Experimental results revealed that Cr(VI) can be reduced to immobile reduced Cr by the HZ sediments in the presence/absence of O2. Anaerobic pre-incubation of the sediments increased the effective rate of Cr reduction that was correlated with the increase in HCl-extractable Fe(II) content in the sediments. The reduced Cr was stable in exposure to O2 under field-relevant pH (~7.5) and Mn-containing (~0.02% w/w) conditions. The Cr(VI) reduction rate showed a multi-rate behavior, apparently reflecting the presence of reductants with different reactivity in the sediments. The results from this study indicated that the HZ sediments can reductively immobilize Cr and the sediment redox capacity can be recharged through microbial activities. The results implied that HZ can play a role as a natural permeable redox barrier for removing groundwater Cr before it discharges into a river system.

  20. Role of U(VI) adsorption in U(VI) Reduction by Geobacter species

    International Nuclear Information System (INIS)

    Lovely, Derrick

    2008-01-01

    Previous work had suggested that Acholeplasma palmae has a higher capacity for uranium sorption than other bacteria studied. Sorption studies were performed with cells in suspension in various solutions containing uranium, and results were used to generate uranium-biosorption isotherms. Results from this study showed that the U(VI) sorption capacity of G. uraniireducens was relatively similar in simple solutions, such as sodium chloride or bicarbonate. However, this ability to sorb uranium significantly decreased in groundwater. This suggested that certain chemicals present in the groundwater were inhibiting the ability of cell components of Geobacter to adsorb uranium. It was hypothesized that uranium removal would also be diminished in the bicarbonate solution. However, this did not seem to be the case, as uranium was as easily removed in the bicarbonate solution as in the sodium chloride solution.

  1. Oxidative stress-related lung dysfunction by chromium(VI): alleviation by Citrus aurantium L.

    Science.gov (United States)

    Soudani, Nejla; Rafrafi, Moez; Ben Amara, Ibtissem; Hakim, Ahmed; Troudi, Afef; Zeghal, Khaled Mounir; Ben Salah, Hichem; Boudawara, Tahia; Zeghal, Najiba

    2013-06-01

    Chromium(VI), a very strong oxidant, causes high cytotoxicity through oxidative stress in tissue systems. Our study investigated the potential ability of ethanolic Citrus aurantium L., family Rutaceae extract, used as a nutritional supplement, to alleviate lung oxidative damage induced by Cr(VI). A high-performance liquid chromatography coupled with a mass spectrometer method was developed to separate and identify flavonoids in C. aurantium L. Six flavonoids were identified, as (1) poncirin, (2) naringin, (3) naringenin, (4) quercetin, (5) isosinensetin, and (6) tetramethyl-o-isoscutellarein. Adult Wistar rats, used in this study, were divided into six groups of six animals each: group I served as controls which received standard diet, group II received via drinking water K2Cr2O7 alone (700 ppm), groups III and IV were pretreated for 10 days with ethanol extract of C. aurantium L. at doses of 100 and 300 mg/kg body weight/day, respectively, and then K2Cr2O7 was administrated during 3 weeks, and groups V and VI received during 10 days only C. aurantium L. ethanol extract at doses of 100 and 300 mg/kg/day, respectively. Ethanol extract of C. aurantium L. was administered orally. Rats exposed to Cr(VI) showed in lung an increase in malondialdehyde and protein carbonyl levels and a decrease in sulflydryl content, glutathione, nonprotein thiol, and vitamins C and E levels. Decreases in enzyme activities such as in Na(+)K(+) ATPase, catalase, glutathione peroxidase, and superoxide dismutase were noted. Pretreatment with C. aurantium L. of chromium-treated rats ameliorated all biochemical parameters. Lung histological studies confirmed the biochemical parameters and the beneficial role of C. aurantium L.

  2. U(VI) extraction by 8-hydroxyquinoline. A comparison study in ionic liquid and in dichloromethane

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Li-Yong; Shi, Wei-Qun [Chinese Academy of Sciences, Beijing (China). Lab. of Nuclear Energy Chemistry; Liao, Xiang-Hong [Chinese Academy of Sciences, Beijing (China). Lab. of Nuclear Energy Chemistry; East China Institute of Technology, Nanchang (China). School of Nuclear Engineering and Geophysics; Liu, Zhi-Rong [East China Institute of Technology, Nanchang (China). School of Nuclear Engineering and Geophysics; Chai, Zhi-Fang [Chinese Academy of Sciences, Beijing (China). Lab. of Nuclear Energy Chemistry; Soochow Univ., Suzhou (China). School of Radiological and Interdisciplinary Sciences and Collaborative Innovation Center of Radiation Medicine

    2017-08-01

    Room temperature ionic liquids (RTILs) represent a recent new class of solvents with potential application in liquid/liquid extraction based nuclear fuel reprocessing due to their unique physical and chemical properties. The work herein provides a comparison of U(VI) extraction by 8-hydroxyquinoline (HOX) in a commonly used RTIL, i.e. 1-butyl-3-methylimidazolium hexafluorophosphate ([C{sub 4}mim][PF{sub 6}]) and in conventional solvent, i.e. dichloromethane (CH{sub 2}Cl{sub 2}). The effect of HOX concentration, solution acidity and nitrate ions on the extraction were discussed in detail, and the speciation analyses of the extracted U(VI) were performed. One of the main emphasis of this work is the extraction mechanism of U(VI) extracted from aqueous phase into RTILs and conventional solvent. In CH{sub 2}Cl{sub 2}, the extraction occurs through a combination of ion change and neutral complexation, and the extracted complex is proposed as UO{sub 2}(OX){sub 2}HOX. In [C{sub 4}mim][PF{sub 6}], although a cation-change mechanism as previously reported for RTILs-based system was involved, the extracted complex of UO{sub 2}(OX){sub 1.5}(HOX){sub 1.5}(PF6){sub 0.5} gave a clear indication that the usage of HOX as an acidic extractant markedly inhibited the solubility loss of [C{sub 4}mim][PF{sub 6}] during the extraction by leaching H{sup +} to aqueous phase. Moreover, the extracted U(VI) in [C{sub 4}mim][PF{sub 6}] can be easily stripped by using 0.01 M nitric acid, which provides a simple way of the ionic liquid recycling.

  3. Health & Demographic Surveillance System Profile: The Birbhum population project (Birbhum HDSS).

    Science.gov (United States)

    Ghosh, Saswata; Barik, Anamitra; Majumder, Saikat; Gorain, Ashoke; Mukherjee, Subrata; Mazumdar, Saibal; Chatterjee, Kajal; Bhaumik, Sunil Kumar; Bandyopadhyay, Susanta Kumar; Satpathi, BiswaRanjan; Majumder, Partha P; Chowdhury, Abhijit

    2015-02-01

    The Birbhum HDSS was established in 2008 and covers 351 villages in four administrative blocks in rural areas of Birbhum district of West Bengal, India. The project currently follows 54 585 individuals living in 12557 households. The population being followed up is economically underprivileged and socially marginalized. The HDSS, a prospective longitudinal cohort study, has been designed to study changes in population demographic, health and healthcare utilization. In addition to collecting data on vital statistics and antenatal and postnatal tracking, verbal autopsies are being performed. Moreover, periodic surveys capturing socio-demographic and economic conditions have been conducted twice. Data on nutritional status (children as well as adults), non-communicable diseases, smoking etc. have also been collected in special surveys. Currently, intervention studies on anaemia, undernutrition and common preschool childhood morbidities through behavioural changes are under way. For access to the data, a researcher needs to send a request to the Data Manager [suri.shds@gmail.com]. Data are shared in common formats like comma-separated files (csv) or Microsoft Excel (xlsx) or Microsoft Access Database (mdb).The HDSS will soon upgrade its data management system to a more integrated platform, coordinated and guided by INDEPTH data sharing policy. © The Author 2014; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

  4. [Adsorptive Stabilization of Soil Cr (VI) Using HDTMA Modified Montmorillonite].

    Science.gov (United States)

    2016-03-15

    A series of organo-montomorillonites were prepared using Na-montomorillonite and hexadecyl trimethyl ammonium bromide (HDTMA). The organo-montomorillonites were then investigated for the remediation of Cr(VI) contaminated soils. FT-IR, XRD, SEM and N2 -BET, CEC, Zeta potential measurement were conducted to understand the structural changes of montmorillonites as different amounts of HDTMAs were added as modifier. The characterization results indicated that the clay interlayer spacing distance increased from 1. 25 nm to 2. 13 nm, the clay surface roughness decreased, the clay surface area reduced from 38.91 m² · g⁻¹ to 0.42 m² · g⁻¹, the clay exchangeable cation amount reduced from 62 cmol · kg⁻¹ to 9.9 cmol · kg⁻¹ and the clay surface charge changed from -29.1 mV to 5.59 mV as the dosage of HDTMA in montmorillonite was increased. The TCLP (toxicity characteristic leaching procedure) was used to evaluate the leachate toxicity of Cr(VI). The effects of the initial soil Cr(VI) concentration, montmorillonites dosage, reaction time and HDTMA modification amount were investigated, respectively. The results revealed that modification of montmorillonites would manifest an attenuated physical adsorptive effect and an enhanced electrostatic adsorptive effect on Cr(VI), suggesting electrostatic effect was the major force that resulted in improved Cr(VI) adsorption onto HDTMA modified montmorillonites.

  5. The Agr communication system provides a benefit to the populations of Listeria monocytogenes in soil

    Directory of Open Access Journals (Sweden)

    Anne-Laure eVivant

    2014-11-01

    Full Text Available In this study, we investigated whether the Agr communication system of the pathogenic bacterium Listeria monocytogenes was involved in adaptation and competitiveness in soil. Alteration of the ability to communicate, either by deletion of the gene coding the response regulator AgrA (response-negative mutant or the signal pro-peptide AgrD (signal-negative mutant, did not affect population dynamics in soil that had been sterilised but survival was altered in biotic soil suggesting that the Agr system of L. monocytogenes was involved to face the complex soil biotic environment. This was confirmed by a set of co-incubation experiments. The fitness of the response-negative mutant was lower either in the presence or absence of the parental strain but the fitness of the signal-negative mutant depended on the strain with which it was co-incubated. The survival of the signal-negative mutant was higher when co-cultured with the parental strain than when co-cultured with the response-negative mutant. These results showed that the ability to respond to Agr communication provided a benefit to listerial cells to compete. These results might also indicate that in soil, the Agr system controls private goods rather than public goods.

  6. Effect of tillage system on yield and weed populations of soybean ( Glycin Max L.

    Directory of Open Access Journals (Sweden)

    Seyed Z. Hosseini

    2016-03-01

    Full Text Available Field experiment was conducted at Agricultural and Natural Resources Research Center of Golestan Province, Iran, to determine the effects of tillage system and weed management regime on yield and weed populations in soybean ( Glycin max L.. The experimental design was a split plot where the whole plot portion was a randomized complete block with three replicates. Main plots were tillage system: 1- No-till row crop seeding, 2- No-till seed drilling, 3- Tillage with disc harrow and drill planting, 4- Tillage with chisel packer and drill planting. The subplots were weed management regimes: 1-Weed control with herbicide application, 2- Hand weeding, 3- Herbicide application plus hand weeding, and 4- Non-weeding. Results indicated that the main effects of tillage system and weed management regime were significant for seed yield, pod number per plant, seed number per pod, weed density and biomass, while their interaction were significant only for weed density, weed biomass, and seed number per pod. The highest grain yields (3838 kg ha-1 were recorded for No-till row crop seeding. The highest seed yield (3877 kg ha-1 also was recorded for weed control with herbicide and hand weeding treatment, followed by hand weeding (3379 kg ha-1.

  7. The Changes of Earthworm Population and Chemical Properties of Tropical Soils under Different Land Use Systems

    Directory of Open Access Journals (Sweden)

    Sri Yusnaini

    2008-05-01

    Full Text Available Hilly area Sumberjaya, West Lampung Province, South Sumatra, Indonesia, is one of the Province where deforestation increasing in the past 30 years as a result of the implementation of agricultural systems, especially coffee plantation. it is important to study the soil fauna in these natural relicts. Six sites (3 naturals and 3 managed systems were studied in order to identify earthworm species communities, using the hand sorting method and soil chemical parameters (pH, avail-P, org-C., tot-N, and cation exchange capacity (CEC. Two species were found (Pheretima sp. and Pontoscolex sp.. All land use systems had very similar soil chemical characteristics, there can be characterised as acidic (pH between 3.6 and 5.0. A high content of organic carbon was in natural sites (bush 4.0% and primary forest 3.9%, and a low content was in managed sites (coffee plantation 2.1%. Total nitrogen (0.37% and CEC (21.84 Cmol-c kg-1 was in primary forest. However, the earthworm densities were significantly lower under primary forest than in the other sites. The acidity component explained mainly the lowest earthworm population at the primary forest (soil pH 3.6. The use of succession forest (bush and mix farming showed a positive effect on soil fertility.

  8. Study of Acari and Collembola Populations in Four Cultivation Systems in Dourados - MS

    Directory of Open Access Journals (Sweden)

    Rosilda Mara Mussury

    2002-09-01

    Full Text Available The impact four cultivation systems on the soil fauna was studied, using Oribatida and Gamasida acarids as bioindicators and collembolan. The research was carried out in experimental fields, located in EMBRAPA - CPAO in Dourados, Centerwest of Brazil from July 1997 to December 1999. The constant pasture system presented smaller impact on the soil fauna followed by agricultural cattle rotation and a direct plantation system. In the conventional plantation series, the populational density of the mesofauna organisms was low, especially collembolan families.O impacto de quatro sistemas de cultivo sobre a fauna de solo foram estudados, utilizando-se como bioindicadores os acari Oribatida e Gamasida e os Collembola. A pesquisa foi conduzida em campos experimentais, localizados na EMBRAPA - CPAO no município de Dourado