WorldWideScience

Sample records for cristal comparisons lead

  1. CRISTAL-ISE your project

    CERN Document Server

    Rosaria Marraffino

    2014-01-01

    CRISTAL-ISE, a new version of the CRISTAL data tracking software developed at CERN in the late 90s, has recently been launched under an open source license. The potential for applications of this free software outside particle physics covers several areas, including medicine, where CRISTAL-ISE helps to monitor the progress of Alzheimer’s Disease.   CMS lead tungstate crystals produced in Russia. CRISTAL began as a collaboration between CERN, the University of the West of England (UWE) and the Centre National de la Recherche Scientifique (CNRS).“At the time of CMS’s construction, there was a need for software able to track the production of the almost 80,000 lead tungstate crystals for the Electromagnetic Calorimeter,” explains Andrew Branson, member of the CMS collaboration and Technical Coordinator of the CRISTAL-ISE project. “We started to develop the software when we didn’t yet know the detector testing procedures to go through,...

  2. El tren de cristal

    Directory of Open Access Journals (Sweden)

    Antonio Orejudo

    2011-12-01

    Full Text Available La historia de la literatura está escrita por los desobedientes, por los escritores que no respetaron las normas de los géneros que cultivaron. Por eso es tan habitual que las grandes obras literarias, las verdaderas innovaciones, sufran en un primer momento la incomprensión del lector. La primera reacción del lector cuando toma entre sus manos una novela adscrita a un género determinado que sin embargo viola los elementos que definen tal género, es de rechazo. Algo de esto sucede con El tren de cristal, la primera novela de José María Pérez Collados, que se ofrece como novela de campus, y que al mismo tiempo se salta las reglas del género en el que aparentemente se inscribe.

  3. TOVALOP and CRISTAL. 2. ed.

    International Nuclear Information System (INIS)

    1990-01-01

    The Torrey Canyon incident in 1967 provided a major stimulus to the development of four international regimes (two voluntary agreements and two international conventions) through which compensation for pollution damage and clean-up costs is available following the escape or discharge of persistent oil from tankers. The two voluntary agreements were set up as a result of the determination of the tanker and oil industries to take constructive action, both to encourage prompt and effective clean-up and to assure adequate and timely compensation, prior to the widespread ratification and acceptance of the two international conventions. The voluntary agreements are the Tanker Owners Voluntary Agreement concerning Liability for Oil Pollution (TOVALOP) and the Contract Regarding a Supplement to Tanker Liability for Oil Pollution (CRISTAL). It should be emphasised from the outset that whilst both TOVALOP and CRISTAL are described as voluntary agreements, it is only the decision on whether or not to participate that is voluntary, since having become a party there is a contractual obligation to meet all the terms and conditions of the applicable agreement. This booklet provides a brief summary of TOVALOP and CRISTAL and their relation to the corresponding international conventions developed under the auspices of the International Maritime Organization (IMO), viz the International Convention on Civil Liability for Oil Pollution Damage, 1969 (CLC) and the International Convention on the Establishment of an International Fund for Compensation for Oil Pollution Damage, 1971 (Fund Convention). (author)

  4. Pantallas de cristal líquido

    OpenAIRE

    CSIC-UZA - Instituto de Ciencia de Materiales de Aragón (ICMA)

    2010-01-01

    Trabajo presentado como material divulgativo a la II Escuela de Materiales: "Aplicaciones de los Cristales Líquidos", en el marco del XI Congreso Nacional de Materiales, organizado por la Sociedad Española de Materiales y el ICMA.

  5. Termómetros de cristal líquido

    OpenAIRE

    CSIC-UZA - Instituto de Ciencia de Materiales de Aragón (ICMA)

    2010-01-01

    Trabajo presentado como material divulgativo a la II Escuela de Materiales: "Aplicaciones de los Cristales Líquidos", en el marco del XI Congreso Nacional de Materiales, organizado por la Sociedad Española de Materiales y el ICMA.

  6. CRISTAL V1: Criticality package for burn up credit calculations

    International Nuclear Information System (INIS)

    Gomit, Jean-Michel; Cousinou, Patrick; Gantenbein, Francoise; Diop, Cheikh; Fernandez de Grado, Guy; Mijuin, Dominique; Grouiller, Jean-Paul; Marc, Andre; Toubon, Herve

    2003-01-01

    The first version of the CRISTAL package, created and validated as part of a joint project between IRSN, COGEMA and CEA, was delivered to users in November 1999. This fruitful cooperation between IRSN, COGEMA and CEA has been pursued until 2003 with the development and the validation of the package CRISTAL V1, whose main objectives are to improve the criticality safety studies including the Burn up Credit effect. (author)

  7. CRISTAL V2 Package: Principles and validation domain

    International Nuclear Information System (INIS)

    Gomit, Jean-Michel; Cochet, Bertrand; Leclaire, Nicolas; Carmouze, Coralie; Damian, Frederic; Entringer, Arnaud; Gagnier, Emmanuel

    2017-04-01

    The purpose of this document is to provide a comprehensive and global view of the CRISTAL V2 package. In particular, it sets out the principles of the computational approaches available to the user, through four calculation 'routes': - the 'multigroup Monte Carlo' route, - the 'multigroup deterministic' route, - the 'point-wise Monte Carlo' route, - the 'criticality standard calculation' route. (authors)

  8. Detector Construction Management and Quality Control Establishing and Using a CRISTAL System

    CERN Document Server

    Le Goff, J.M.; Bazan, A.; Le Flour, T.; Lieunard, S.; Murray, S.; Vialle, J.P.; Baker, N.; Estrella, F.; Kovacs, Z.; McClatchey, R.; Organtini, G.; Bityukov, S.

    1998-01-01

    The CRISTAL (Cooperating Repositories and an Information System for Tracking Assembly Lifecycles) project is delivering a software system to facilitate the management of the engineering data collected at each stage of production of CMS. CRISTAL captures all the physical characteristics of CMS components as each sub-detector is tested and assembled. These data are retained for later use in areas such as detector slow control, calibration and maintenance. CRISTAL must, therefore, support different views onto its data dependent on the role of the user. These data viewpoints are investigated in this paper. In the recent past two CMS Notes have been written about CRISTAL. The first note, CMS 1996/003, detailed the requirements for CRISTAL, its relationship to other CMS software, its objectives and reviewed the technology on which it would be based. CMS 1997/104 explained some important design concepts on which CRISTAL is and showed how CRISTAL integrated the domains of product data man- agement and workflow manage...

  9. Towards Provenance and Traceability in CRISTAL for HEP

    CERN Document Server

    Shamdasani, Jetendr; McClatchey, Richard

    2014-01-01

    This paper discusses the CRISTAL object lifecycle management system and its use in provenance data management and the traceability of system events. This software was initially used to capture the construction and calibration of the CMS ECAL detector at CERN for later use by physicists in their data analysis. Some further uses of CRISTAL in different projects (CMS, neuGRID and N4U) are presented as examples of its flexible data model. From these examples, applications are drawn for the High Energy Physics domain and some initial ideas for its use in data preservation HEP are outlined in detail in this paper. Currently investigations are underway to gauge the feasibility of using the N4U Analysis Service or a derivative of it to address the requirements of data and analysis logging and provenance capture within the HEP long term data analysis environment.

  10. The graphical user interface for CRISTAL V1

    International Nuclear Information System (INIS)

    Heulers, L.; Courtois, G.; Fernex, F.; Gomit, J.M.; Letang, E.

    2003-01-01

    This paper deals with the new Graphical User Interface (GUI) of the CRISTAL V1 package devoted to criticality studies including burn up calculations. The aim of this GUI is to offer users a high level of user-friendliness and flexibility in the data description and the results analysis of codes of the package. The three main components of the GUI (CIGAIES, EJM and OPOSSUM) are presented. The different functionalities of the tools are explained through some applications. (author)

  11. Comparison of lead residues among avian bones

    International Nuclear Information System (INIS)

    Ethier, A.L.M.; Braune, B.M.; Scheuhammer, A.M.; Bond, D.E.

    2007-01-01

    To determine if significant differences exist in lead (Pb) accumulation in different bones, especially those most often used for bone-Pb studies in wildlife, we compared Pb concentrations in radius, ulna, humerus, femur, and tibia of Common Eider (Somateria mollissima); and radius/ulna (combined), femur, and tibia of American Woodcock (Scolopax minor). There were no significant differences in bone-Pb concentrations among woodcock bones over a wide range of Pb concentrations (3-311 μg/g). In eider, where bone-Pb concentrations were low (<10 μg/g), leg bones had significantly higher Pb concentrations (approximately 30-40%) than wing bones from the same individuals. The variation among individual birds was greater than the variation among different bones within a bird. Based on our findings, we conclude that one type of bone may be substituted for another in bone-Pb studies although the same bone type should be analyzed for all birds within a study, whenever possible. - Variability in Pb concentrations among avian bones

  12. Comparison of the radiological and chemical toxicity of lead

    Energy Technology Data Exchange (ETDEWEB)

    Beitel, G.A.; Mott, S.

    1995-03-01

    This report estimates the worst-case radiological dose to an individual from ingested lead containing picocurie levels of radionuclides and then compares the calculated radiological health effects to the chemical toxic effects from that same lead. This comparison provides an estimate of the consequences of inadvertently recycling, in the commercial market, lead containing nominally undetectable concentrations of radionuclides. Quantitative expressions for the radiological and chemical toxicities of lead are based on concentrations of lead in the blood stream. The result shows that the chemical toxicity of lead is a greater health hazard, by orders of magnitude, than any probable companion radiation dose.

  13. Comparison of the radiological and chemical toxicity of lead

    International Nuclear Information System (INIS)

    Beitel, G.A.; Mott, S.

    1995-03-01

    This report estimates the worst-case radiological dose to an individual from ingested lead containing picocurie levels of radionuclides and then compares the calculated radiological health effects to the chemical toxic effects from that same lead. This comparison provides an estimate of the consequences of inadvertently recycling, in the commercial market, lead containing nominally undetectable concentrations of radionuclides. Quantitative expressions for the radiological and chemical toxicities of lead are based on concentrations of lead in the blood stream. The result shows that the chemical toxicity of lead is a greater health hazard, by orders of magnitude, than any probable companion radiation dose

  14. El techo de Cristal en México

    Directory of Open Access Journals (Sweden)

    María Elena Camarena Adame

    2018-01-01

    Full Text Available El “techo de cristal” son los obstáculos que impiden que una mujer alcance puestos de alto nivel en las organizaciones. El objetivo de este trabajo es analizar la situación actual de las mujeres en los puestos de alta dirección en el contexto mexicano, con el fin de conocer qué tanto el techo de cristal afecta su desarrollo profesional. Para ello se realizó una investigación documental recolectando información de las empresas que cotizan en la Bolsa Mexicana de Valores ( bmv , así como de publicaciones recientes del sector empresarial en México. El principal hallazgo de este trabajo muestra que en promedio, las mujeres que conforman el consejo de administración en las empresas que cotizan en la bmv, sólo alcanzan el 4.56 %, asimismo, de las 500 mejores empresas para trabajar en México, sólo el 3% se encuentran dirigidas por mujeres, y de las 50 mujeres más poderosas de México, sólo el 14% trabajan como ejecutivas en una empresa. Ello evidencia que a pesar de los avances referentes a la igualdad de género, aún resulta difícil para las mujeres superar el techo de cristal.

  15. Efectos no lineales fotoinducidos en cristales líquidos

    Directory of Open Access Journals (Sweden)

    Juan A. Reyes

    2001-01-01

    Full Text Available Se presentan dos ejemplos en los que se aplica un formalismo analítico que permite describir una amplia variedad de fenómenos no lineales que ocurren cuando un campo óptico se propaga en un cristal líquido. Primero se describe la propagación de ondas planas en celdas rectangulares formadas por cristales líquidos nemáticos, tomando en cuenta su acoplamiento con la orientación. Posteriormente se analiza la propagación de un paquete de ondas en la celda. Se muestra que existe un efecto de guía de ondas en la propagación de los campos ópticos y que los modos transversales magnéticos (TM de la radiación electromagnética se pueden propagar como solitones ópticos. En ausencia de absorción, se calculan explícitamente diversas propiedades de los solitones.

  16. Obtención de Relaciones Cuantitativas Estructura-Propiedad en Cristales Líquidos Obtención de Relaciones Cuantitativas Estructura-Propiedad en Cristales Líquidos

    Directory of Open Access Journals (Sweden)

    Maria Reyna Hernández

    2012-02-01

    Full Text Available Sixty nine thermotropic liquid crystal molecules were analyzed by different chemometric methods, including Principal Component Analysis (PCA, Genetic algorithms and Quantitative Structure-Property Relationships (QSPR. Mathematical models to predict nematic transition temperatures (TN were derived. This is the first time that Principal Component Analysis was used to predict liquid crystal properties, leading to the derivation of local (specific models for different molecule sets. Results indicate that local models have higher prediction capabilities than global models, which is consistent to our initial assumption. This methodology will be used in the study of liquid crystals used in pharmaceutical applications.Una serie de 69 cristales líquidos termotrópicos se sometió a una colección de Métodos Quimiométricos incluyendo Análisis de Componentes Principales; Algoritmos Genéticos y Relaciones Cuantitativas Estructura Propiedad para la obtención de modelos matemáticos que permitan predecir las Temperaturas de Transición Nemática, (TN. En este trabajo se aplica por primera vez el Análisis de Componentes Principales al estudio de cristales líquidos para la identifi cación de subconjuntos de moléculas para los cuales se obtuvieron modelos locales. Los resultados obtenidos muestran que la capacidad de predicción de los modelos locales es superior a la del modelo global, lo cual resultó consistente con la hipótesis planteada. La metodología utilizada se extenderá al estudio de cristales líquidoscon actividad farmacológica.

  17. Hydrogen generation comparison between lead-calcium and lead-antimony batteries in nuclear power plant

    International Nuclear Information System (INIS)

    Zhao Hongjun; Qi Suoni; Shen Yan; Li Jia

    2014-01-01

    Battery type selection is performed with the help of technical information supplied by vendors, and according to relevant criteria. Analysis and comparison of the hydrogen generation differences between two different lead-acid battery types are carried out through calculation. The analysis result may provide suggestions for battery type selection in nuclear power plant. (authors)

  18. Development and experimental qualification of the new safety-criticality CRISTAL package; Developpement et qualification experimentale du nouveau formulaire de surete-criticite Cristal

    Energy Technology Data Exchange (ETDEWEB)

    Mattera, Ch

    1998-11-01

    This thesis is concerned with Criticality-Safety studies related to the French Nuclear Fuel Cycle. We first describe the steps in the nuclear fuel cycle and the specific characteristics of these studies compared with those performed in Reactor Physics. In order to respond to the future requirements of the French Nuclear Program, we have developed a new package CRISTAL based on a recent cross sections library (CEA 93) and the newest accurate codes (APOLLO 2, MORET 4, TRIPOLI 4). The CRISTAL system includes two calculations routes: a design route which will be used by French Industry (COGEMA/SGN) and a reference route. To transfer this package to the French industry, we have elaborated calculation schemes for fissile solutions, dissolver media, transport casks and storage pools. Afterwards, these schemes have been used for the CRISTAL experimental validation. We have also contributed to the CRISTAL experimental database by reevaluating a French storage pool experiment: the CRISTO II experiment. This revaluation has been submitted to the OECD working group in order that this experiment can be used by international criticality safety engineers to validate calculations methods. This work represents a large contribution to the recommendation of accurate calculation schemes and to the experimental validation of the CRISTAL package. These studies came up to the French Industry expectations. (author)

  19. Development and experimental testing of the new safety-criticality Cristal package; Developpement et qualification experimentale du nouveau formulaire de surete-criticite Cristal

    Energy Technology Data Exchange (ETDEWEB)

    Mattera, Ch

    1998-11-10

    This thesis is concerned with Criticality-Safety studies related to the French Nuclear Fuel Cycle. We first describe the steps in the nuclear fuel cycle and the specific characteristics of these studies compared with those performed in Reactor Physics. In order to respond to the future requirements of the French Nuclear Program, we have developed a new package CRISTAL based on a recent cross sections library (CEA93) and the newest accurate codes (APOLLO2, MORET4, TRIPOLI4). The cristal system includes two calculations routes: a design route which will be used by French Industry (COGEMA/SGN) and a reference route.) To transfer this package to the French industry, we have elaborated calculation schemes for fissile solutions, dissolver media, transport casks and storage pools. Afterwards, these schemes have been used for the CRISTAL experimental validation. We have also contributed to the CRISTAL experimental database by reevaluating a French storage pool experiment: the CRISTO II experiment. This revaluation has been submitted to the OCDE working group in order that this experiment can be used by international criticality safety engineers to validate calculations methods. This work represents a large contribution to the recommendation of accurate calculation schemes and to the experimental validation of the CRISTAL package. These studies came up to the French Industry expectations. (author) 70 refs.

  20. Development and experimental qualification of the new safety-criticality CRISTAL package

    International Nuclear Information System (INIS)

    Mattera, Ch.

    1998-11-01

    This thesis is concerned with Criticality-Safety studies related to the French Nuclear Fuel Cycle. We first describe the steps in the nuclear fuel cycle and the specific characteristics of these studies compared with those performed in Reactor Physics. In order to respond to the future requirements of the French Nuclear Program, we have developed a new package CRISTAL based on a recent cross sections library (CEA 93) and the newest accurate codes (APOLLO 2, MORET 4, TRIPOLI 4). The CRISTAL system includes two calculations routes: a design route which will be used by French Industry (COGEMA/SGN) and a reference route. To transfer this package to the French industry, we have elaborated calculation schemes for fissile solutions, dissolver media, transport casks and storage pools. Afterwards, these schemes have been used for the CRISTAL experimental validation. We have also contributed to the CRISTAL experimental database by reevaluating a French storage pool experiment: the CRISTO II experiment. This revaluation has been submitted to the OECD working group in order that this experiment can be used by international criticality safety engineers to validate calculations methods. This work represents a large contribution to the recommendation of accurate calculation schemes and to the experimental validation of the CRISTAL package. These studies came up to the French Industry expectations. (author)

  1. Development and experimental testing of the new safety-criticality Cristal package

    International Nuclear Information System (INIS)

    Mattera, Ch.

    1998-01-01

    This thesis is concerned with Criticality-Safety studies related to the French Nuclear Fuel Cycle. We first describe the steps in the nuclear fuel cycle and the specific characteristics of these studies compared with those performed in Reactor Physics. In order to respond to the future requirements of the French Nuclear Program, we have developed a new package CRISTAL based on a recent cross sections library (CEA93) and the newest accurate codes (APOLLO2, MORET4, TRIPOLI4). The cristal system includes two calculations routes: a design route which will be used by French Industry (COGEMA/SGN) and a reference route.) To transfer this package to the French industry, we have elaborated calculation schemes for fissile solutions, dissolver media, transport casks and storage pools. Afterwards, these schemes have been used for the CRISTAL experimental validation. We have also contributed to the CRISTAL experimental database by reevaluating a French storage pool experiment: the CRISTO II experiment. This revaluation has been submitted to the OCDE working group in order that this experiment can be used by international criticality safety engineers to validate calculations methods. This work represents a large contribution to the recommendation of accurate calculation schemes and to the experimental validation of the CRISTAL package. These studies came up to the French Industry expectations. (author)

  2. Oscilador para biosensores basado en microbalanza de cristal de cuarzo (QCM

    Directory of Open Access Journals (Sweden)

    Yeison Javier Montagut Ferizzola

    2011-01-01

    Full Text Available El cristal de cuarzo generalmente es usado en aplicaciones como microbalanza, aprovechando la capacidad que presenta éste para variar su frecuencia de resonancia de acuerdo a los cambios de la densidad superficial de masa depositada en la superficie del resonador. De esta manera, un cristal de cuarzo puede ser utilizado como transductor en un sistema de inmunosensor piezoeléctrico, para detectar uniones antígeno - anticuerpo. En este artículo se presenta una interfaz para microbalanzasde cristal de cuarzo, QCM (del inglés Quartz Crystal Microbalance basado en una versión mejorada de oscilador en configuración diferencial equilibrado y su validación como sistema de caracterización para biosensores. El sistema fue probado con éxito en un inmunosensor piezoeléctrico para la detección del plaguicida Carbaryl.

  3. Naturaleza fractal en redes de cristales de grasas

    Directory of Open Access Journals (Sweden)

    Gómez Herrera, C.

    2004-06-01

    Full Text Available The determination of the mechanical and rheological characteris­tics of several plastic fats requires a detailed understanding of the microstructure of the fat crystal network aggregates. The (or A fractal approach is useful for the characterization of this micros­tructure. This review begins with information on fractality and statistical self-similar structure. Estimations for fractal dimension by means of equations relating the volume fraction of solid fat to shear elastic modulus G' in linear region are described. The influence of interesterification on fractal dimension decrease (from 2, 46 to 2 ,15 for butterfat-canola oil blends is notable . This influence is not significant for fat blends without butterfat. The need for an increase in research concerning the relationship between fractality and rheology in plastic fats is emphasized.La determinación de las características mecánicas y reológicas de ciertas grasas plásticas requiere conocimientos detallados sobre las microestructuras de los agregados que forman la red de cristales grasos. El estudio de la naturaleza fractal de estas microestructuras resulta útil para su carac­terización. Este artículo de información se inicia con descripciones de la dimensión fractal y de la "autosimilitud estadística". A continuación se describe el cálculo de la dimensión fractal mediante ecuaciones que relacionan la fracción en volumen de grasa sólida con el módulo de recuperación (G' dentro de un comportamiento viscoelástico lineal. Se destaca la influencia que la interesterificación ejerce sobre la dimensión fractal de una mezcla de grasa láctea y aceite de canola (que pasa de 2,64 a 2,15. Esta influencia no se presenta en mezclas sin grasa láctea. Se insiste sobre la necesidad de incrementar las investi­gaciones sobre la relación entre reología y estructura fractal en grasas plásticas.

  4. Edificio para Cristalería Española

    Directory of Open Access Journals (Sweden)

    de la Joya, R.

    1964-03-01

    Full Text Available In the course of a series of lectures on the subject of curtain walls, held at the Higher Technical College of Architecture, in Madrid, the author described his own experience whilst constructing a building (designed by him and by Mr. Manuel Barbero for the firm Cristalería Española, at San Andrés del Palomar, Barcelona. Mr. De la Joya summarised the advantages that foreign experts attribute to curtain walls. These advantages are: less weight of the materials of the enclosing walls; maximum use of the available building surface; cheaper foundations; better building time control; superior quality and accuracy; and greater maintenance facility. The lecturer then explained why, and in what aspects, he was in disagreement with the above supposed advantages. He dealt with these as follows: 1. In terms of present day construction, with concrete blocks and lightweight flooring structures, it is not easy to save much weight, owing to the number of special fittings that are necessary to support and keep the curtain wall in place.—2. Although in theory a. curtain wall may be only 4 or 5 cm thick, the truth is that unless heating or air conditioning is provided on a much larger scale, a special internal protection layer is necessary.—3. It is difficult to reduce the cost of the foundations by fitting curtain walls, and any calculated saving in cost in this aspect is more theoretical than real.—4. Building time estimates usually fail to work out in practice, and in addition to this, workmanship quality is not yet very satisfactory.—5. Curtain walls require periodic overhauls, so that they do not age too rapidly, and in this sense they are no better than traditional walls. The lecturer also made a number of additional points, one of them being that he did not advise the use of curtain walls in Spain (because of the cheapness of brickwalls, the climate, the high cost of air conditioning, etc. He also emphasized how important it is to make a very

  5. Comparison of fuel assemblies in lead cooled fast reactors

    Energy Technology Data Exchange (ETDEWEB)

    Perez, A.; Sanchez, H.; Aguilar, L.; Espinosa P, G., E-mail: alejandria.peval@gmail.com [Universidad Autonoma Metropolitana, Unidad Iztapalapa, San Rafael Atlixco No. 186, Col. Vicentina, 09340 Ciudad de Mexico (Mexico)

    2016-09-15

    This paper presents a comparison of the thermal-fluid processes in the core, fuel heat transfer, and thermal power between two fuel assemblies: square and hexagonal, in a lead-cooled fast reactor (Lfr). A multi-physics reduced order model for the analysis of Lfr single channel is developed in this work. The work focused on a coupling between process of neutron kinetic, fuel heat transfer process and thermal-fluid, in a single channel. The thermal power is obtained from neutron point kinetics model, considering a non-uniform power distribution. The analysis of the processes of thermal-fluid considers thermal expansion effects. The transient heat transfer in fuel is carried out in an annular geometry, and one-dimensional in radial direction for each axial node. The results presented in comparing these assemblies consider the temperature field in the fuel, in the thermal fluid and under steady state, and transient conditions. Transients consider flow of coolant and inlet temperature of coolant. The mathematical model of Lfr considers three main modules: the heat transfer in the annular fuel, the power generation with feedback effects on neutronic, and the thermal-fluid in the single channel. The modeling of nuclear reactors in general, the coupling is crucial by the feedback between the neutron processes with fuel heat transfer, and thermo-fluid, where is very common the numerical instabilities, after all it has to refine the model to achieve the design data. In this work is considered as a reference the ELSY reactor for the heat transfer analysis in the fuel and pure lead properties for analyzing the thermal-fluid. The results found shows that the hexagonal array has highest temperature in the fuel, respect to square array. (Author)

  6. Comparison of fuel assemblies in lead cooled fast reactors

    International Nuclear Information System (INIS)

    Perez, A.; Sanchez, H.; Aguilar, L.; Espinosa P, G.

    2016-09-01

    This paper presents a comparison of the thermal-fluid processes in the core, fuel heat transfer, and thermal power between two fuel assemblies: square and hexagonal, in a lead-cooled fast reactor (Lfr). A multi-physics reduced order model for the analysis of Lfr single channel is developed in this work. The work focused on a coupling between process of neutron kinetic, fuel heat transfer process and thermal-fluid, in a single channel. The thermal power is obtained from neutron point kinetics model, considering a non-uniform power distribution. The analysis of the processes of thermal-fluid considers thermal expansion effects. The transient heat transfer in fuel is carried out in an annular geometry, and one-dimensional in radial direction for each axial node. The results presented in comparing these assemblies consider the temperature field in the fuel, in the thermal fluid and under steady state, and transient conditions. Transients consider flow of coolant and inlet temperature of coolant. The mathematical model of Lfr considers three main modules: the heat transfer in the annular fuel, the power generation with feedback effects on neutronic, and the thermal-fluid in the single channel. The modeling of nuclear reactors in general, the coupling is crucial by the feedback between the neutron processes with fuel heat transfer, and thermo-fluid, where is very common the numerical instabilities, after all it has to refine the model to achieve the design data. In this work is considered as a reference the ELSY reactor for the heat transfer analysis in the fuel and pure lead properties for analyzing the thermal-fluid. The results found shows that the hexagonal array has highest temperature in the fuel, respect to square array. (Author)

  7. Germanium enrichment in supergene settings: evidence from the Cristal nonsulfide Zn prospect, Bongará district, northern Peru

    Science.gov (United States)

    Mondillo, Nicola; Arfè, Giuseppe; Herrington, Richard; Boni, Maria; Wilkinson, Clara; Mormone, Angela

    2018-02-01

    Supergene nonsulfide ores form from the weathering of sulfide mineralization. Given the geochemical affinity of Ge to Si4+ and Fe3+, weathering of Ge-bearing sulfides could potentially lead to Ge enrichments in silicate and Fe-oxy-hydroxide minerals, although bulk rock Ge concentrations in supergene nonsulfide deposits are rarely reported. Here, we present the results of an investigation into Ge concentrations and deportment in the Cristal supergene Zn nonsulfide prospect (Bongará, northern Peru), which formed from the weathering of a preexisting Mississippi Valley-type (MVT) sulfide deposit. Material examined in this study originates from drillcore recovered from oxidized Zn-rich bodies 15-20 m thick, containing 5-45 wt% Zn and Ge concentrations 100 ppm. Microanalysis and laser ablation-ICP-MS show that precursor sphalerite is rich in both Fe (mean Fe = 8.19 wt%) and Ge (mean Ge = 142 ppm). Using the mineral geothermometer GGIMFis—geothermometer for Ga, Ge, In, Mn, and Fe in sphalerite—proposed by Frenzel et al. (Ore Geol Rev 76:52-78, 2016), sphalerite trace element data from the Cristal prospect suggest a possible formation temperature ( T GGIMFis) of 225 ± 50 °C, anomalously high for a MVT deposit. Germanium concentrations measured in both goethite (mean values 100 to 229 ppm, max 511 ppm) and hemimorphite (mean values 39 to 137 ppm, max 258 ppm) are similar to concentrations measured in hypogene sphalerite. Additionally, the Ge concentrations recorded in bulk rock analyses of sphalerite-bearing and oxidized samples are also similar. A persistent warm-humid climate is interpreted for the region, resulting in the development of an oxidation zone favoring the formation of abundant Zn hydrosilicates and Fe hydroxides, both able to incorporate Ge in their crystal structure. In this scenario, Ge has been prevented from dispersion during the weathering of the Ge-bearing sulfide bodies and remains in the resultant nonsulfide ore.

  8. Comparison of Sprint Fidelis and Riata defibrillator lead failure rates.

    Science.gov (United States)

    Fazal, Iftikhar A; Shepherd, Ewen J; Tynan, Margaret; Plummer, Christopher J; McComb, Janet M

    2013-09-30

    Sprint Fidelis and Riata defibrillator leads are prone to early failure. Few data exist on the comparative failure rates and mortality related to lead failure. The aims of this study were to determine the failure rate of Sprint Fidelis and Riata leads, and to compare failure rates and mortality rates in both groups. Patients implanted with Sprint Fidelis leads and Riata leads at a single centre were identified and in July 2012, records were reviewed to ascertain lead failures, deaths, and relationship to device/lead problems. 113 patients had Sprint Fidelis leads implanted between June 2005 and September 2007; Riata leads were implanted in 106 patients between January 2003 and February 2008. During 53.0 ± 22.3 months of follow-up there were 13 Sprint Fidelis lead failures (11.5%, 2.60% per year) and 25 deaths. Mean time to failure was 45.1 ± 15.5 months. In the Riata lead cohort there were 32 deaths, and 13 lead failures (11.3%, 2.71% per year) over 54.8 ± 26.3 months follow-up with a mean time to failure of 53.5 ± 24.5 months. There were no significant differences in the lead failure-free Kaplan-Meier survival curve (p=0.77), deaths overall (p=0.17), or deaths categorised as sudden/cause unknown (p=0.54). Sprint Fidelis and Riata leads have a significant but comparable failure rate at 2.60% per year and 2.71% per year of follow-up respectively. The number of deaths in both groups is similar and no deaths have been identified as being related to lead failure in either cohort. Copyright © 2012. Published by Elsevier Ireland Ltd.

  9. The cristal (right superior septal) coronary artery and its relationship to anomalous left coronary origin

    International Nuclear Information System (INIS)

    Partridge, J.B.; Ridley, L.J.

    2011-01-01

    The cristal artery is an occasional finding, being visible in around 3% of coronary angiograms, arising from the proximal right coronary artery (RCA) and passing downwards and forwards through the muscle of the crista superventricularis. It supplies a variable volume of the superior interventricular septum, and can contribute to collateralization of the other septal vessels. When part or all of the left coronary artery (LCA) arises anomalously from the right coronary sinus, its passage to the left may be in the same pathway as a cristal artery, bearing a tell-tale septal vessel arising from its proximal segment. This helps to differentiate it from one that has a higher pathway, running between the great vessels, and which may have a greater correlation with sudden cardiac death.

  10. Criticality benchmark comparisons leading to cross-section upgrades

    International Nuclear Information System (INIS)

    Alesso, H.P.; Annese, C.E.; Heinrichs, D.P.; Lloyd, W.R.; Lent, E.M.

    1993-01-01

    For several years criticality benchmark calculations with COG. COG is a point-wise Monte Carlo code developed at Lawrence Livermore National Laboratory (LLNL). It solves the Boltzmann equation for the transport of neutrons and photons. The principle consideration in developing COG was that the resulting calculation would be as accurate as the point-wise cross-sectional data, since no physics computational approximations were used. The objective of this paper is to report on COG results for criticality benchmark experiments in concert with MCNP comparisons which are resulting in corrections an upgrades to the point-wise ENDL cross-section data libraries. Benchmarking discrepancies reported here indicated difficulties in the Evaluated Nuclear Data Livermore (ENDL) cross-sections for U-238 at thermal neutron energy levels. This led to a re-evaluation and selection of the appropriate cross-section values from several cross-section sets available (ENDL, ENDF/B-V). Further cross-section upgrades anticipated

  11. Comparison of economic activity leading U.S. sports leagues

    Directory of Open Access Journals (Sweden)

    E.A. Strikalenko

    2013-03-01

    Full Text Available The main activities of the leading sports leagues were described. Sources of revenue and expenditure were identified. The economic performance of professional sports leagues of the United States of America was compared. In the course of the study of economic efficiency of the leading American sports leagues are defined payroll (expense commands on the salaries of players for each team, the total payroll in the League and the average payroll, respectively, for each of the American League. The largest estimates on wages, both in the League and in teams - in the National football League, the largest player's contract - in the Highest League baseball, the minimum wage in the National hockey League; the highest average wages, a greater percentage of athletes with a salary of more than 1 million. $ (82,85 % in the National basketball Association were showed. This difference in the maximum income of the League and of average wages is due to several factors: the number of players in the team, the number of games in a season, and expenses on carrying out of competition and training activities.

  12. Study of stripping cristallization processus of AUC with ammonium carbonate

    International Nuclear Information System (INIS)

    Chegrouche, Salah.

    1987-09-01

    This study is concerned with direct crystallization of ammonium uranyl carbonate (AUC) from a uranium loaded organic phase (30% TBP in kerosene), with ammonium carbonate (NH 4 ) 2 CO 3 . The effects of operating conditions ((NH 4 ) 2 CO 3 concentration, flow-ratio, residence time, temperature) on the physical properties of AUC crystals (particle size distribution, specific surface, density...) are reported. All products were identified (both by chemical analysis, X-Ray diffraction) as being ammonium uranyl carbonate crystals (AUC). The results show that a high phase ratio and (NH 4 ) 2 CO 3 concentration favor the formation of fine AUC grains and aggregates. This is due mainly to the high concentration of NH + 4 in the system which leads to a high solution supersaturation and consequently to a rapid formation rate of crystal (germination). The reverse phenomenon is observed at low phase ratio and (NH 4 ) 2 CO 3 concentration, where germination and crystal growth are slow and the product is mainly monocrystal. In the intermediate range, a mixture of polycrystal and aggregates is obtained. Residence and temperature are also shown to have an effect on the processes (the effect of time being more important than temperature). In the course of this study a bench-scale stripper-crystallizer was developped and operated successfully. (author). tables, graphs

  13. The performance of a soluble lead-acid flow battery and its comparison to a static lead-acid battery

    International Nuclear Information System (INIS)

    Zhang, C.P.; Sharkh, S.M.; Li, X.; Walsh, F.C.; Zhang, C.N.; Jiang, J.C.

    2011-01-01

    Highlights: → We compared the electrochemical characteristics of two types of the batteries. → SLAFB shows as good performance as SLAB under the same current density. → The cycle life of two batteries is strongly influenced by the depth of discharge. → The cycle life of SLAFB can be extended by treatment with hydrogen peroxide. - Abstract: The electrochemistry of static lead-acid and soluble lead-acid flow batteries is summarised and the differences between the two batteries are highlighted. A general comparison of the performance of an unoptimised soluble lead-acid flow laboratory cell and a commercial lead-acid battery during charge and discharge is reported. The influence of the depth of discharge on cycle life for both batteries is also considered. The flow battery was found to have a better charge efficiency than the static one, but the cells were found to have comparable energy efficiencies. The self-discharge characteristics of the soluble lead-acid battery were also measured and compared to reported values for a commercial static battery. Some self-discharge of the soluble lead-acid flow battery is observed during prolonged periods on open-circuit but the battery could recover its normal performance after a single charge-discharge cycle.

  14. Estudio mediante resonancia magnética de efectos pretransicionales en cristales líquidos

    OpenAIRE

    Vaca Chavez, Fabián

    2002-01-01

    Tesis (Doctor en Física)--Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física, 2002. Se presenta el estudio mediante la técnica de Resonancia Magnética Nuclear de los efectos pretransicionales en diferentes fases de cristales líquidos termotrópicos y liotrópicos. Estos compuestos son materia de innumerables trabajos tanto teóricos como experimentales, debido a que son materiales extremadamente interesantes por sus aplicaciones tecnológicas, ópticas y biológicas. Se...

  15. Determination of lead in whole blood: Comparison of the LeadCare blood lead testing system with zeeman longitudinal electrothermal atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Pineau, A.; Viallefont, A.; Fauconneau, B.; Rafael, M.; Guillard, O.

    2002-01-01

    This study compares the efficiency of blood lead level analysis by graphite furnace atomic absorption spectrometry (GFAAS) and the portable LeadCare Blood lead testing system (LCS). Recoveries of two added lead concentrations of 22 and 42 μg/dL ranged from 102.4 to 105.5% for LCS and from 96.3 to 97.2% for GFAAS. Measurement of a certified sample (Certified Danish Whole Blood) at a blood lead concentration of 26.2 μg/dL gave within- and between-run coefficients of variation which were both approximately 8% by LCS and 2% by GFAAS. Comparison of the tested method (LCS) versus GFAAS from analysis of 76 samples of blood lead collected from workers in different industrial sectors showed imperfect overall correlation (r = 0.95). The LCS is quite suitable for screening purposes, but requires the use of non-frozen blood collected less than 24 h before. Conservative threshold values should be applied when using the LCS for initial screening in the field. (orig.)

  16. La fábrica de cristal y vidrio de Santa Lucía (Cartagena y el sector del vidrio español (1834-1908

    Directory of Open Access Journals (Sweden)

    Martínez Carrión, J. M.

    2002-06-01

    Full Text Available This article is a contribution to the Spanish glass industry from the knowledge of Fabrica de Cristal y Vidrio de Santa Lucia (Cartagena during the XIXth century. The evolution of this company is accomplished within the context of the Spanish sector underlining some phases: Its impulse during 1840´s and 1850´s, market problems and competition in the last decades of the XIXth century, and its restructuring at the beginning of the XXth century, which ended with an intense process of concentration and internationalization that affected plane glass and hollow glass. Likewise, industrial location factors, regional distribution of the production, and changes occurred in its various branches between 1856 and 1905 are reported. Data reveal the leading role of this factory from Cartagena in the glass industry and, particularly, its specialization in crystal, glassware of best quality, and white cut glass during the Restoration period.

    El trabajo contribuye al conocimiento de la industria del vidrio español durante el siglo XIX a partir de la Fábrica de Cristal y Vidrio de Santa Lucia (Cartagena. La evolución de la empresa es analizada en el contexto del sector español, destacándose varias fases: el impulso que vivió el sector en las décadas de 1840 y 1850, los problemas de mercado y competitividad en las décadas finales del siglo XIX y la reestructuración de comienzos del siglo XX. Esta última acabó con la formación de estructuras de oligopolio que afectaron a las ramas del vidrio plano y del vidrio hueco. Se destacan, asimismo, los factores de localización industrial, la distribución regional de la producción y los cambios acaecidos en sus diferentes ramas entre 1856 y 1905. Los datos aportados revelan el protagonismo de la empresa de Cartagena en el sector vidriero, y en particular su especialización en cristal y vidrio blanco tallado durante el periodo de la Restauración.

  17. Software data acquisition system for the ''Chateau de Cristal'' multicounter 74 BaF2

    International Nuclear Information System (INIS)

    Adzama, G.

    1985-01-01

    The ''Chateau de Cristal'' is a 74 BaF2 detector assembly. Other detectors such as Ge (up to 12) and particle detectors can be added to this multidetector. The data acquisition system hardware and software are implemented in 3 VME crates. The operating system is handled by 68000 Motorola microprocessors. This work is dedicated to the initialization and control tasks of the multidetector. Handling of high voltage power supply for the 74 BaF2 detectors via a RS 232 C serial port, CAMAC initialization for the ADC 4300 Lecroy and DFC modules, data exchange between the 3 VME crates and automatic energy calibration for the BaF2 detectors. All the software is written in 68000 Motorola assembly language [fr

  18. Urna de cristal como canal digital de participación ciudadana en Colombia

    Directory of Open Access Journals (Sweden)

    John Edickson Amaya-Rodríguez

    2017-01-01

    Full Text Available En este artículo se describen se describe la normativa vigente en Colombia referente al gobierno electrónico. Asimismo, se hace referencia las diferentes herramientas utilizadas por la estrategia urna de cristal del gobierno colombiano. Asimismo, se evalúa su alcance en la ciudadanía tanto con los informes publicados por esta estrategia, así como a través de una encuesta realizada en la totalidad de los departamentos del país. Finalmente se proponen unas recomendaciones que pueden ser consideradas en el desarrollo de las actividades del canal seleccionado con el objetivo que se pueda ampliar la cobertura de dicho canal y se pueda tener un efectivo acercamiento de los ciudadanos al gobierno a través de herramientas tecnológicas.

  19. Reduction of lead pollution from vehicular emissions in cairo Part 1: Comparison of alternative solutions

    International Nuclear Information System (INIS)

    El-Haggar, S.M.; Saleh, S.K.; El-Kady, M.A.

    1996-01-01

    It has been recognized for decades that the major source of lead pollution is lead additives to automotive fuels. This problem has been countered in most countries in europe and Usa by introducing alternative anti-knock chemicals and unleaded gasoline. In egypt lead is still being added to gasoline in large quantities. However, progress has been made, and unleaded gasoline is currently being produced in Alexandria. Nevertheless, the major pollution problem remains in the Greater Cairo region as indicated by the atmospheric lead levels and the lead blood levels of the children in Cairo. The aim of the present study is to find an optimum solution to this problem. A comparison of the different solutions is conducted in order to come up with the most feasible solution to this urgent problem. In conclusion it has been demonstrated that the elimination of lead additives, with its huge positives effects on the country environment, proved to be profitable. 4 figs., 2 tabs

  20. Classical fluoroscopy criteria poorly predict right ventricular lead septal positioning by comparison with echocardiography.

    Science.gov (United States)

    Squara, Fabien; Scarlatti, Didier; Riccini, Philippe; Garret, Gauthier; Moceri, Pamela; Ferrari, Emile

    2018-03-13

    Fluoroscopic criteria have been described for the documentation of septal right ventricular (RV) lead positioning, but their accuracy remains questioned. Consecutive patients undergoing pacemaker or defibrillator implantation were prospectively included. RV lead was positioned using postero-anterior and left anterior oblique 40° incidences, and right anterior oblique 30° to rule out coronary sinus positioning when suspected. RV lead positioning using fluoroscopy was compared to true RV lead positioning as assessed by transthoracic echocardiography (TTE). Precise anatomical localizations were determined with both modalities; then, RV lead positioning was ultimately dichotomized into two simple clinically relevant categories: RV septal or RV free wall. Accuracy of fluoroscopy for RV lead positioning was then assessed by comparison with TTE. We included 100 patients. On TTE, 66/100 had a septal RV lead and 34/100 had a free wall RV lead. Fluoroscopy had moderate agreement with TTE for precise anatomical localization of RV lead (k = 0.53), and poor agreement for septal/free wall localization (k = 0.36). For predicting septal RV lead positioning, classical fluoroscopy criteria had a high sensitivity (95.5%; 63/66 patients having a septal RV lead on TTE were correctly identified by fluoroscopy) but a very low specificity (35.3%; only 12/34 patients having a free wall RV lead on TTE were correctly identified by fluoroscopy). Classical fluoroscopy criteria have a poor accuracy for identifying RV free wall leads, which are most of the time misclassified as septal. This raises important concerns about the efficacy and safety of RV lead positioning using classical fluoroscopy criteria.

  1. Caracterización de cristales de calcita bioprecipitada por un aislamiento nativo de Bacillus subtilis

    Directory of Open Access Journals (Sweden)

    Carolina Montoya

    2007-02-01

    Full Text Available Bacillus subtilis es una bacteria útil en algunas aplicaciones biotecnológicas por poseer enzimas como las amilasas, las cuales desempeñan un papel importante en diferentes procesos industriales. Una de sus propiedades, poco estudiada, ha sido su capacidad de inducir bioprecipitación química de carbonato de calcio (Ca2+ + HCO3 3> CaCO3 + H+ mediante un mecanismo similar al observado en la formación de rocas, suelos y estructuras biológicas como huesos, conchas y dientes. En esta investigación se estudiaron los cristales producidos por un aislamiento nativo de B. subtilis, tomado de una mina de oro situada en Segovia (Antioquia. Se determinó su capacidad calcificante utilizando el medio de cultivo B4. La caracterización del cristal producido se realizó con lupa binocular, microscopio petrográfico de luz plana polarizada (MOLP en su modo de luz transmitida, microscopio electrónico de barrido con analizador de estado sólido (ESEM/EDX y espectroscopía infrarroja con transformada de Fourier (FTIR. A partir de los resultados obtenidos por medio de la caracterización utilizando la combinación de las técnicas analíticas que se mencionaron, fue posible determinar que el aislado nativo de B. subtilis generó y por ende es productor de cristales de carbonato de calcio (CaCO3 en su forma polimórfica de baja temperatura (calcite.Palabras clave: Bacillus subtilis, calcita, bioprecipitación, mineralogía aplicada, biomineralogía.ABSTRACTBacillus subtilis, a bacterium useful in some biotechnology applications, contains enzymes such as amylases, which play an important role in several industrial processes. One of its properties, not very well studied, is its capacity to induce the chemical bioprecipitation of CaCO3 (Ca2+ + HCO3 —> CaCO3 + H+, a similar mechanism commonly observed in the formation of rocks, soils and biological structures like bones, shells and teeth. In this work we have studied carbonate crystals produced by a B

  2. Caracterización de cristales de calcita bioprecipitada por un aislamiento nativo de Bacillus subtilis

    Directory of Open Access Journals (Sweden)

    Carolina Montoya

    2005-07-01

    Full Text Available Bacillus subtilis es una bacteria útil en algunas aplicaciones biotecnológicas por poseer enzimas como las amilasas, las cuales desempeñan un papel importante en diferentes procesos industriales. Una de sus propiedades, poco estudiada, ha sido su capacidad de inducir bioprecipitación química de carbonato de calcio (Ca2+ + HCO3 3> CaCO3 + H+ mediante un mecanismo similar al observado en la formación de rocas, suelos y estructuras biológicas como huesos, conchas y dientes. En esta investigación se estudiaron los cristales producidos por un aislamiento nativo de B. subtilis, tomado de una mina de oro situada en Segovia (Antioquia. Se determinó su capacidad calcificante utilizando el medio de cultivo B4. La caracterización del cristal producido se realizó con lupa binocular, microscopio petrográfico de luz plana polarizada (MOLP en su modo de luz transmitida, microscopio electrónico de barrido con analizador de estado sólido (ESEM/EDX y espectroscopía infrarroja con transformada de Fourier (FTIR. A partir de los resultados obtenidos por medio de la caracterización utilizando la combinación de las técnicas analíticas que se mencionaron, fue posible determinar que el aislado nativo de B. subtilis generó y por ende es productor de cristales de carbonato de calcio (CaCO3 en su forma polimórfica de baja temperatura (calcite.Palabras clave: Bacillus subtilis, calcita, bioprecipitación, mineralogía aplicada, biomineralogía.ABSTRACTBacillus subtilis, a bacterium useful in some biotechnology applications, contains enzymes such as amylases, which play an important role in several industrial processes. One of its properties, not very well studied, is its capacity to induce the chemical bioprecipitation of CaCO3 (Ca2+ + HCO3 —> CaCO3 + H+, a similar mechanism commonly observed in the formation of rocks, soils and biological structures like bones, shells and teeth. In this work we have studied carbonate crystals produced by a B

  3. Skin toxicology of lead species evaluated by their permeability and proteomic profiles: a comparison of organic and inorganic lead.

    Science.gov (United States)

    Pan, Tai-Long; Wang, Pei-Wen; Al-Suwayeh, Saleh A; Chen, Chih-Chieh; Fang, Jia-You

    2010-08-01

    Lead compounds are known to cause cytotoxicity and genotoxicity. Lead absorption by the skin is an important route through which this metal enters the body. The purpose of this work was to evaluate the skin permeability and toxicological profiles of two lead species, lead acetate and lead nitrate. This study assessed lead-induced toxicity mechanisms by focusing on the histopathology, proteomics, cell growth, and cellular ATP. In vitro skin permeation assays showed that there was no significant difference of lead accumulation within and across the skin between the two lead species. The presence of simulated sweat reduced the skin uptake of lead. The skin deposition of lead acetate was greater than that of lead nitrate with in vivo topical application. On the other hand, lead nitrate produced greater changes in the skin's histology and proteomic profiles compared to lead acetate. Four protein spots which showed significant changes were identified and are discussed in this study. These included glucose-related protein precursor (GRP) 78, K14, alpha-actin, and Rho GDP-dissociation inhibitor 2 (RhoGDI2). These proteins are respectively associated with oxidative stress, apoptosis, wound healing, and proliferation. Lead presented a biphasic pattern on cell growth and intracellular ATP content, with a stimulating effect at low concentrations and an inhibitory effect on cell proliferation at higher concentrations. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  4. I cristalli sonici come barriere antirumore - Sonic crystals as tunable noise barriers

    Directory of Open Access Journals (Sweden)

    Federica Morandi

    2017-02-01

    Full Text Available Il presente contributo riporta un'introduzione al tema della propagazione del suono nei cristalli sonici e un excursus sulla letteratura scientifica più recente. Si discutono i risultati di alcune indagini sperimentali condotte presso l’Università di Bologna inerenti misure di Insertion Loss, misure effettuate all’interno del reticolo e misure di intensimetria. Infine i valori di Sound Insulation misurati per un cristallo sonico sono confrontati con valori misurati su barriere tradizionali, evidenziando come il cristallo sonico permetta di raggiungere un isolamento confrontabile con il valore soglia di Insertion Loss raggiungibile a causa della diffrazione del bordo superiore della barriera. ------ This work reports an introduction to the topic of wave propagation in sonic crystals and a review of the recent scientific literature. The paper presents the results of some experimental investigations carried out at the University of Bologna by discussing Insertion Loss measurements, measurements performed inside the lattice and sound intensity measurements. Finally, the Sound Insulation Index measured for a sonic crystal is compared to the values measured for common noise barriers, pointing out that sonic crystals reach insulation values comparable to the maximum Insertion Loss achievable due to the top edge diffraction.

  5. Electrohidrodinámica de cristales líquidos nemáticos

    Directory of Open Access Journals (Sweden)

    Rosalío F. Rodríguez

    2001-01-01

    Full Text Available Se presenta un formalismo analítico que permite describir una amplia variedad de fenómenos ópticos no lineales que ocurren cuando una onda electromagnética se propaga en un cristal líquido. A partir de propiedades termodinámicas y de simetría, primero se construye un conjunto cerrado de ecuaciones hidrodinámicas que proporcionan una descripción completa de la dinámica de un nemático de bajo peso molecular en ausencia de campos externos. Posteriormente, se incluye la presencia de un campo electromagnético externo que se propaga en el fluido. Se discute el carácter no lineal y acoplado de las ecuaciones y, para resolverlas, se propone un método iterativo de aproximaciones sistemáticas en términos de potencias de parámetros con una interpretación física precisa. Se concluye discutiendo las ventajas y limitaciones del punto de vista adoptado en este trabajo..

  6. Aquatic Coleoptera from El Cristal Natural Reserve (Santa Fe Province, Argentina

    Directory of Open Access Journals (Sweden)

    Gabriel A. MACCHIA

    2015-01-01

    Full Text Available Se presenta una lista de los coleópteros acuáticos colectados en la Reserva Natural El Cristal. Se identificaron 77 especies incluidas en 35 géneros y seis familias. Diez géneros se citan por primera vez de la provincia de Santa Fe: Copelatus Erichson, Anodocheilus Babington, Bidessodes Régimbart, Bidessonotus Régimbart, Pachydrus Sharp, Laccomimus Toledo & Michat (Dytiscidae, Mesonoterus Sharp (Noteridae, Pelonomus Erichson (Dryopidae, Chaetarthria Stephens y Paracymus Thomson (Hydrophilidae. Además, 17 especies se registran por primera vez de la provincia de Santa Fe: Thermonectus succinctus (Aubé, Anodocheilus maculatus Babington, Bidessonotus obtusatus Régimbart, Pachydrus globosus (Aubé, P. obesus Sharp (Dytiscidae, Hydrocanthus paraguayensis Zimmermann, Mesonoterus laevicollis Sharp, Suphis freudei Mouchamps, Suphisellus curtus (Sharp, S. grammicus (Sharp, S. nigrinus (Aubé, S. remator (Sharp (Noteridae, Chaetarthria bruchi Balfour-Browne, Enochrus sublongus (Fall, Berosus paraguayanus Knisch, Derallus altus (Leconte y Phaenonotum regimbarti Bruch (Hydrophilidae.

  7. Comparison between steel and lead shieldings for radiotherapy rooms regarding neutron doses to patients

    Energy Technology Data Exchange (ETDEWEB)

    Silva, M.G.; Rebello, W.F.; Andrade, E.R.; Medeiros, M.P.C.; Mendes, R.M.S.; Braga, K.L.; Gomes, R.G., E-mail: eng.cavaliere@gmail.com, E-mail: ggrprojetos@gmail.com [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil). Secao de Engenharia Nuclear; Silva, A.X., E-mail: ademir@con.ufrj.br [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    The NCRP Report No. 151, Structural Shielding Design and Evaluation for Megavoltage X- and Gamma-Ray Radiotherapy Facilities, considers, in shielding calculations for radiotherapy rooms, the use of lead and/or steel to be applied on bunker walls. The NCRP Report calculations were performed foreseeing a better protection of people outside the radiotherapy room. However, contribution of lead and steel to patient dose should be taken into account for radioprotection purposes. This work presents calculations performed by MCNPX code in analyzing the Ambient Dose Equivalent due to neutron, H *(10){sub n}, within a radiotherapy room, in the patients area, considering the use of additional shielding of 1 TVL of lead or 1 TVL of steel, positioned at the inner faces of walls and ceiling of a bunker. The head of the linear accelerator Varian 2100/2300 C/D was modeled working at 18MeV, with 5 x 5 cm{sup 2}, 10 x 10 cm{sup 2}, 20 x 20 cm{sup 2}, 30 x 30 cm{sup 2} and 40 x 40 cm{sup 2} openings for jaws and MLC and operating in eight gantry's angles. This study shows that the use of lead generates an average value of H *(10){sub n} at patients area, 8.02% higher than the expected when using steel. Further studies should be performed based on experimental data for comparison with those from MCNPX simulation. (author)

  8. Comparison between steel and lead shieldings for radiotherapy rooms regarding neutron doses to patients

    International Nuclear Information System (INIS)

    Silva, M.G.; Rebello, W.F.; Andrade, E.R.; Medeiros, M.P.C.; Mendes, R.M.S.; Braga, K.L.; Gomes, R.G.

    2015-01-01

    The NCRP Report No. 151, Structural Shielding Design and Evaluation for Megavoltage X- and Gamma-Ray Radiotherapy Facilities, considers, in shielding calculations for radiotherapy rooms, the use of lead and/or steel to be applied on bunker walls. The NCRP Report calculations were performed foreseeing a better protection of people outside the radiotherapy room. However, contribution of lead and steel to patient dose should be taken into account for radioprotection purposes. This work presents calculations performed by MCNPX code in analyzing the Ambient Dose Equivalent due to neutron, H *(10) n , within a radiotherapy room, in the patients area, considering the use of additional shielding of 1 TVL of lead or 1 TVL of steel, positioned at the inner faces of walls and ceiling of a bunker. The head of the linear accelerator Varian 2100/2300 C/D was modeled working at 18MeV, with 5 x 5 cm 2 , 10 x 10 cm 2 , 20 x 20 cm 2 , 30 x 30 cm 2 and 40 x 40 cm 2 openings for jaws and MLC and operating in eight gantry's angles. This study shows that the use of lead generates an average value of H *(10) n at patients area, 8.02% higher than the expected when using steel. Further studies should be performed based on experimental data for comparison with those from MCNPX simulation. (author)

  9. Lead isotopic compositions of environmental certified reference materials for an inter-laboratory comparison of lead isotope analysis

    International Nuclear Information System (INIS)

    Aung, Nyein Nyein; Uryu, Tsutomu; Yoshinaga, Jun

    2004-01-01

    Lead isotope ratios, viz. 207 Pb/ 206 Pb and 208 Pb/ 206 Pb, of the commercially available certified reference materials (CRMs) issued in Japan are presented with an objective to provide a data set, which will be useful for the quality assurance of analytical procedures, instrumental performance and method validation of the laboratories involved in environmental lead isotope ratio analysis. The analytical method used in the present study was inductively coupled plasma quadrupole mass spectrometry (ICPQMS) presented by acid digestion and with/without chemical separation of lead from the matrix. The precision of the measurements in terms of the relative standard deviation (RSD) of triplicated analyses was 0.19% and 0.14%, for 207 Pb/ 206 Pb and 208 Pb/ 206 Pb, respectively. The trueness of lead isotope ratio measurements of the present study was tested with a few CRMs, which have been analyzed by other analytical methods and reported in various literature. The lead isotopic ratios of 18 environmental matrix CRMs (including 6 CRMs analyzed for our method validation) are presented and the distribution of their ratios is briefly discussed. (author)

  10. Dispositivos de cristal líquido dopados con nanopartículas = Nanoparticle-doped liquid crystal devices

    OpenAIRE

    García García, Amanda

    2017-01-01

    Esta Tesis Doctoral se centra en el estudio del dopado de cristal líquido (CL) con nanopartículas conductoras y semiconductoras y en su interacción mutua. El dopado con nanopartículas modifica muchas propiedades de los materiales. Concretamente, los nanotubos de carbono (CNTs) han demostrado ser nanopartículas anisótropas capaces de cambiar propiedades eléctricas y ópticas de los CL dependiendo de la orientación relativa del CNT con la aplicación del campo eléctrico. Los CNTs son nanopartícu...

  11. Comparison of the key mechanisms leading to rollovers in Liquefied Natural Gas using Computational Fluid Dynamics

    Science.gov (United States)

    Hubert, Antoine; Dadonau, Maksim; Dembele, Siaka; Denissenko, Petr; Wen, Jennifer

    2017-11-01

    Growing demand for the LNG fosters growth of the number of production sites with varying composition and density. Combining different sources of LNG may result in a stably stratified system, in which heat and mass transfer between the layers is limited. Heating of the LNG due to wall thermal conductivity leads to formation of convection cells confined within the layers. While the upper layer can release the extra energy via preferential methane boil-off, the bottom layer cannot and hence becomes superheated. Gradual density equilibration reduces stratification and may eventually lead to a sudden mixing event called ``rollover'', accompanied by violent evaporation of the superheated LNG. Three phenomena are potentially responsible for density equilibration. The first is the growing difference in thermal expansion of the layers due to the reduced ability of the bottom layer to reject heat. The second is the penetration of the heated near-wall boundary layer into the upper layer. The third is the ``entrainment mixing'' occurring at the contact surface between the two layers. The present study uses CFD to compare these mechanisms. Boussinesq approximation and an extended version of the k- ɛ model is used. The code is validated by comparison with a large-scale LNG rollover experiment.

  12. The continuing impact of lead dust on children's blood lead: comparison of public and private properties in New Orleans.

    Science.gov (United States)

    Mielke, Howard W; Gonzales, Chris R; Mielke, Paul W

    2011-11-01

    Compared with a maximum collective lead (Pb) estimate of ∼1811 metric tons (MT) in exterior paint on 86,000 New Orleans houses, Pb additives in gasoline were estimated at ∼12,000 MT in New Orleans, yielding ∼9100 MT Pb exhausted as aerosols from vehicles; ∼4850 MT were particles>10 μm and ∼4200 MT were particles New Orleans. This study includes 224 soil samples from 10 public housing properties and 363 soil samples from residential private properties within an 800 m radius of centroids of public housing census tracts. The Louisiana Childhood Lead Poisoning Prevention Program data from 2000 to 2005 (pre-Hurricane Katrina) was the source for 9807 children's blood Pb (μg/dL) results. Soil and blood Pb data were grouped by public housing census tracts and private residential properties. This study uses Multi-Response Permutation Procedures for statistical analysis. Brick public properties in the city core had significantly more soil Pb contamination and higher prevalence of elevated children's blood Pb than same-aged brick public properties in the outer areas of the city. The pre-Hurricane Katrina New Orleans concentration of Pb dust in the inner-city soil displayed a median of 438 mg/kg or 3.7 times larger than Pb dust in outlying areas where the median soil Pb was 117 mg/kg (p-value=2.9×10(-15)). Also, the pre-Hurricane Katrina prevalence of children's blood Pb≥10 μg/dL was 22.9% within the inner-city compared with 9.1% in the outer areas of New Orleans (p-value=3.4×10(-74)). Comparing the quantities of Pb dust from paint and Pb additives to gasoline, this study supports the later source as a more plausible explanation for the differences in soil Pb and children's blood Pb within public and private housing in the higher traffic congested inner-city core compared with the lower traffic congested outer areas of New Orleans. Similar patterns of environmental Pb dust contamination and childhood Pb exposure are expected in all cities. Copyright © 2011

  13. Precise adjustment of the orientation of a crystal mounted on a goniometric head; Reglage precis de l'orientation d'un cristal monte sur une tete goniometrique

    Energy Technology Data Exchange (ETDEWEB)

    Tournarie, M [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires; Curien, H [Laboratoire de Mineralogie-Cristallographie, Sorbonne, 75 - Paris (France)

    1959-07-01

    Trigonometric calculus required to give the orientation of a crystal with a good accuracy, is presented in order to show the use of an E 101 computer. (author) [French] Les calculs trigonometriques necessaires pour orienter d'une maniere precise un cristal sont presentes en vue de leur execution sur une machine E 101. (auteur)

  14. Comparison of five in vitro digestion models to in vivo experimental results: Lead bioaccessibility in the human gastrointestinal tract

    NARCIS (Netherlands)

    Wiele, T.R. van de; Oomen, A.G.; Wragg, J.; Cave, M.; Minekus, M.; Hack, A.; Cornelis, C.; Rompelberg, C.J.M.; Zwart, L.L. de; Klinck, B.; Wijnen, J. van; Verstraete, W.; Sips, A.J.A.M.

    2007-01-01

    This paper presents a multi-laboratory comparison study of in vitro models assessing bioaccessibility of soil-bound lead in the human gastrointestinal tract under simulated fasted and fed conditions. Oral bioavailability data from a previous human in vivo study on the same soil served as a reference

  15. Identification and comparison of lead white of the 15-th century Gdansk panel paintings by neutron activation analysis

    International Nuclear Information System (INIS)

    Olszewska-Swietlik, J.; Panczyk, E.

    2005-01-01

    The lead white has been used in painting science the middle ages both as a priming ground and pigment. Purity of the lead white is directly connected with the lead purification methods that have undergone considerable changes throughout centuries. Marked progress in this respect was noted in the 19-th century. That is why determination of such elements a Ag, Hg, Zn, Cu, Co, Cr, Ba and Sb in the lead white gives reliable information regarding the age of the painting in question. Analyses of samples of the lead white taken from genuine 15-th century panel paintings representing the so-called Pomeranian school were carried out using instrumental neutron activation analysis technique. The total of 32 elements were determined in those samples; also the comparison of the data for Malopolska and Silesian schools was performed. (author)

  16. Comparison of the U.S. lead recycling industry in 1998 and 2011

    Science.gov (United States)

    Wilburn, David R.

    2014-01-01

    Since 1998, the structure of the lead recycling industry has changed and trade patterns of the domestic lead recycling industry have shifted. Although the domestic demand for lead has remained relatively constant since 1998, production of lead has increasingly shifted to the domestic secondary lead industry. The last primary lead smelter in the United States closed at the end of 2013, at which time the secondary lead industry became the sole source of domestic lead production. The amount of lead recovered annually from scrap batteries generally increased from about 900,000 metric tons in 1995 to more than 1,100,000 metric tons in 2012. The percentage of total U.S. lead production attributed to battery scrap increased from 65 percent in 1995 to 87 percent in 2012. Since the North American Free Trade Agreement took effect in 1994, trade patterns among the United States, Canada, and Mexico have changed for recycled lead products. In the late 1990s, the principal sources of lead waste and scrap not derived from batteries were Canada, Mexico, and South America; by 2011, the principal sources were Central America and Asia, with decreasing amounts from Canada and South America. Since 1998, the amount of lead derived from imported batteries and scrap from Canada has ranged from 50 to 90 percent, and the amount imported from Mexico has ranged from 3 to 20 percent. Canada received about 50 percent of the lead contained in spent lead-acid batteries and scrap exported from the United States in 1998, and Mexico received about 4 percent. By 2012, however, the amount of lead scrap exported to Canada had decreased to about 10 percent, and the amount of lead-based scrap products, primarily batteries, exported to Mexico from the United States had increased to 47 percent. Vertical integration of the domestic secondary lead industry and higher costs required to implement more stringent ambient air standards in the United States have led some companies to shift lead recycling

  17. RETRACTED ARTICLE: Happiness as alchemy: Positive mood leads to self-serving responses to social comparisons

    OpenAIRE

    Johnson, Camille S.; Stapel, Diederik A.

    2011-01-01

    People in a positive mood process information in ways that reinforce and maintain this positive mood. The current studies examine how positive mood influences responses to social comparisons and demonstrates that people in a positive mood interpret ambiguous information about comparison others in self-benefitting ways. Specifically, four experiments demonstrate that compared to negative mood or neutral mood participants, participants in a positive mood engage in effortful re-interpretations o...

  18. Interlaboratory Comparison of Lead and Cadmium in Blood, Urine, and Aqueous Solutions

    DEFF Research Database (Denmark)

    Paulev, P. E.; Solgaard, Per Bent; Tjell, Jens Christian

    1978-01-01

    Analysis for lead and cadmium in biological liquids (blood and urine) is difficult. Results of such analyses from five laboratories are compared for samples with known additions of lead and cadmium. The data, evaluated in terms of inter- and intralaboratory reproducibility and accuracy, suggest t...... that laboratories should voluntarily participate in quality control programs. Users of routine laboratories are advised to use their own quality control program......Analysis for lead and cadmium in biological liquids (blood and urine) is difficult. Results of such analyses from five laboratories are compared for samples with known additions of lead and cadmium. The data, evaluated in terms of inter- and intralaboratory reproducibility and accuracy, suggest...

  19. Pacemaker Implantation Associated Myocardial Micro-Damage: A Randomised Comparison between Active and Passive Fixation Leads.

    Science.gov (United States)

    Blažek, Patrick; Ferri-Certić, Jerko; Vražić, Hrvoje; Lennerz, Carsten; Grebmer, Christian; Kaitani, Kazuaki; Karch, Martin; Starčević, Boris; Semmler, Verena; Kolb, Christof

    2018-03-20

    Fixation of the pacemaker leads during pacemaker implantation leads to an increase of cardiac Troponin T (cTnT) that can be interpreted as a sign of minimal myocardial damage. This trial evaluates whether the mechanism type of lead fixation influences the magnitude of cTnT release. Patients having a de-novo cardiac pacemaker implantation or a lead revision were centrally randomized to receive either a ventricular lead with an active (screw) or passive (tine) fixation mechanism. High-sensitive Troponin T (hsTnT) was determined on the day of the procedure beforehand and on the following day. 326 Patients (median age (IQR) 75.0 (69.0-80.0) years, 64% male) from six international centers were randomized to receive ventricular leads with an active (n = 166) or passive (n = 160) fixation mechanism. Median (IQR) hsTnT levels increased by 0.009 (0.004-0.021) ng/ml in the group receiving screw-in ventricular leads and by 0.008 (0.003-0.030) ng/ml in the group receiving tined ventricular leads (n.s.). In conclusion pacemaker implantations are followed by a release of hsTnT. The choice between active or passive fixation ventricular leads does not have a significant influence on the extent of myocardial injury and the magnitude of hsTnT release.

  20. Determination of lead in red wine for CCQM-K30 international comparison by using ID-ICPMS

    International Nuclear Information System (INIS)

    Zhou Tao; Wang Jun; Lu Hai; Zhao Motian

    2007-01-01

    The content of lead in red wine for CCQM-K30 international key comparison is determined by using isotope dilution mass spectrometry (IDMS). This test almost reach detect limit of the method because the content of lead in red wine was only 3 ng/g and the procedure blank was about 0.3 ng. The comparison results indicate that it is easy to achieve agreements using IDMS. In uncertainty analysis, all of the factors about IDMS method were considered. But, procedure blank took great inference to experiment precision and enlarged the total uncertainty. Therefore the controls of procedure blank were very important for the analysis of ultra-trace concentration of samples. (authors)

  1. Exportación a Nueva España de manufacturas de la Real Fábrica de Cristales de San Ildefonso (1760-1763

    Directory of Open Access Journals (Sweden)

    María Teresa Ruiz Alcón

    1994-01-01

    Full Text Available La Real Fábrica de Cristales de San Ildefonso, cuyos orígenes se remontan al año 1727, fecha en la que Felipe V concedió una licencia a los maestros catalanes Buena Ventura Sit y Carlos Sac para instalar un taller de manufactura de vidrio en el Real Sitio de San Ildefonso, pasó a ser Real Fábrica de Cristales y Espejos en 1745 por iniciativa del monarca, con el ánimo de fomentar la producción nacional y evitar la importación de productos extranjeros. La fábrica dependía directamente de la Corona y administrativamente, de la Secretaría de Estado.

  2. Embryonic exposure to lead: comparison of immune and cellular responses in unchallenged and virally stressed chickens

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ji-Eun; Kao, Elizabeth; Dietert, Rodney R. [Institute for Comparative and Environmental Toxicology, College of Veterinary Medicine, Cornell University, Ithaca, NY (United States); Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY (United States); Naqi, Syed A. [Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY (United States)

    2002-01-01

    Lead, a ubiquitous environmental contaminant, has been shown to modulate various functions of the immune system and decrease host resistance to infectious disease. However, limited information is available concerning the direct effects of lead on the host immune response to an infectious agent after developmental exposure. The current study utilized chickens to examine the effect of embryonic lead exposure on immune and cellular responses during viral challenge. Sublethal doses of lead were introduced into fertilized Cornell K Strain White Leghorn chicken eggs via the air sac at day 5 or day 12 of embryonic development (designated as E5 and E12, respectively). Four-week-old female chickens were inoculated with infectious bronchitis virus (IBV) strain M41. Antibody titer to IBV, delayed-type hypersensitivity (DTH) response against bovine serum albumin (BSA), the absolute number and percentage of leukocyte subpopulations, and interferon-{gamma} (IFN-{gamma})-like cytokine production by splenocytes were evaluated at 5-6 weeks of age. While antibody response to IBV in juvenile chicks was unaffected by the in ovo lead exposure, IFN-{gamma}-like cytokine production by splenocytes was significantly depressed following lead exposure at both developmental stages. In contrast with this pattern, the DTH response against BSA was unaffected following E5 exposure, but was significantly decreased after E12 exposure to lead. These changes were similar to those previously reported in chickens not exposed to IBV. While lead exposure at E5 induced significant changes in the percentage of circulating heterophils at 1 day postinfection (dpi), lead did not cause any change in relative leukocyte counts after E12 exposure. At 7 dpi, E5 lead exposure resulted in decreased absolute number and percentage of circulating lymphocytes, while total leukocyte counts, and the absolute number and percentage of circulating monocytes and heterophils were significantly reduced in E12 lead

  3. Perspective on Lead Toxicity, a Comparison between the United States and Iran

    Directory of Open Access Journals (Sweden)

    Maryann Amirshahi

    2012-10-01

    Full Text Available Lead is a pervasive toxin that has been implicated in human poisonings throughout history.Exposure mitigation strategies in the United States and worldwide have led to a decline in symptomatic poisonings and population blood lead levels; however, lead remains a major health hazard. In this article, we review the history of lead toxicity, clinical manifestations ranging from subclinical and subtle features to life-threatening complications, and thesubsequent public health interventions in the US. In addition, we explore common routes of lead exposure and the unique differences between the US and Iran. Although the US has made significant strides with regard to this public health issue, lead poisoning in both countries continues to be a health hazard in the adult and pediatric populations. It is also critical to consider natural disasters and reconstruction efforts as potential sources of leadcontamination. In conclusion, we make recommendations that both the US and Iranian authorities can implement to eradicate lead as a public health hazard.

  4. Experimental comparison of gamma attenuations by glasses, lead, iron and concretes

    International Nuclear Information System (INIS)

    Charamathieu, Andre; Papot, Lucien

    1964-08-01

    The authors report the experimental determination, for lead glasses of density 3.3, 4.2, 5.2 and 6.2, of thicknesses equivalent to thicknesses given for lead, iron, ordinary concrete and barite concrete for Cobalt 60 and Caesium 137 radiations. Results are presented under the form of curves. Attenuation measurements made on this opportunity and those made on various hot cells have been compared with theoretical attenuation curves produced in another CEA document [fr

  5. ESTUDIO DE LOS FACTORES QUE INFLUYEN EN LA FORMA Y PROPIEDADES DE LOS CRISTALES Y PROPUESTAS PARA LOS ESTUDIANTES DE PROFESORADO DE SECUNDARIA EN GEOLOGÍA

    Directory of Open Access Journals (Sweden)

    Carmen Reyero

    2013-01-01

    Full Text Available En el presente artículo se hace un estudio de la influencia del medio en la estructura y propiedades de los cristales y su importancia a nivel industrial. Consta de una revisión bibliográfica de cómo se han conseguido cambiar la estructura de los cristales de cloruro de sodio variando las condiciones de cristalización, obteniendo, de esta forma, cristales que facilitan el manejo industrial de este producto o mejoran su solubilidad. Por último, se añade una propuesta para trabajar con estudiantes de máster de formación de profesorado de secundaria de la especialidad de geología. La valoración de este trabajo por parte de los alumnos del máster durante los tresaños que se ha llevado a cabo ha sido inmejorable, y ellos lo han aplicado con estudiantes de secundaria.

  6. Identification of Zn-Bearing Micas and Clays from the Cristal and Mina Grande Zinc Deposits (Bongará Province, Amazonas Region, Northern Peru

    Directory of Open Access Journals (Sweden)

    Giuseppe Arfè

    2017-11-01

    Full Text Available Zn-bearing phyllosilicates are common minerals in nonsulfide Zn deposits, but they seldom represent the prevailing economic species. However, even though the presence of Zn-bearing clays is considered as a disadvantage in mineral processing, their characteristics can give crucial information on the genesis of the oxidized mineralization. This research has been carried out on the Mina Grande and Cristal Zn-sulfide/nonsulfide deposits, which occur in the Bongará district (Northern Peru. In both of the deposits, Zn-bearing micas and clays occur as an accessory to the ore minerals. The XRD analyses and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS investigations revealed that the Zn-bearing micas that are occurring in both deposits mostly consist of I/S mixed layers of detrital origin, which have been partly altered or overprinted by sauconite during the supergene alteration of sulfides. Sporadic hendricksite was also identified in the Cristal nonsulfide mineral assemblage, whereas at Mina Grande, the fraipontite-zaccagnaite (3R-polytype association was detected. The identified zaccagnaite polytype suggests that both fraipontite and zaccagnaite are genetically related to weathering processes. The hendricksite detected at Cristal is a product of hydrothermal alteration, which is formed during the emplacement of sulfides. The complex nature of the identified phyllosilicates may be considered as evidence of the multiple processes (hydrothermal and supergene that occurred in the Bongará district.

  7. Performance comparison of metallic, actinide burning fuel in lead-bismuth and sodium cooled fast reactors

    International Nuclear Information System (INIS)

    Weaver, K.D.; Herring, J.S.; Macdonald, P.E.

    2001-01-01

    Various methods have been proposed to ''incinerate'' or ''transmute'' the current inventory of transuranic waste (TRU) that exits in spent light-water-reactor (LWR) fuel, and weapons plutonium. These methods include both critical (e.g., fast reactors) and non-critical (e.g., accelerator transmutation) systems. The work discussed here is part of a larger effort at the Idaho National Engineering and Environmental Laboratory (INEEL) and at the Massachusetts Institute of Technology (MIT) to investigate the suitability of lead and lead-alloy cooled fast reactors for producing low-cost electricity as well as for actinide burning. The neutronics of non fertile fuel loaded with 20 or 30-wt% light water reactor (LWR) plutonium plus minor actinides for use in a lead-bismuth cooled fast reactor are discussed in this paper, with an emphasis on the fuel cycle life and isotopic content. Calculations show that the average actinide burn rate is similar for both the sodium and lead-bismuth cooled cases ranging from -1.02 to -1.16 g/MWd, compared to a typical LWR actinide generation rate of 0.303 g/MWd. However, when using the same parameters, the sodium-cooled case went subcritical after 0.2 to 0.8 effective full power years, and the lead-bismuth cooled case ranged from 1.5 to 4.5 effective full power years. (author)

  8. Comparison of methods for certification of stannic, stibium and lead traces in reference materials for steel

    Directory of Open Access Journals (Sweden)

    I. V. Khodakovskaya

    2016-01-01

    Full Text Available Development and introduction of new metallurgical technologies, new additional chemical compound indexes controlled in metallurgical materials demand to develop the new, more advanced methods of analytical control. The particular attention should be paid to identify the traces of stannic, stinium and lead because of their influence on metal characteristics.

  9. Comparison of three jet events to predictions from a next-to-leading order calculation

    Energy Technology Data Exchange (ETDEWEB)

    Brandl, Alexander [Univ. of New Mexico, Albuquerque, NM (United States)

    2002-01-01

    The properties of three-jet events in data of integrated luminosity 86±4 pb-1 from CDF Run 1b and with total transverse energy greater than 175 GeV have been analyzed and compared to predictions from a next-to-leading order perturbative QCD calculation.

  10. Comparison between Clinically Used Irregular Fields Shielded by Cerrobend and Standard Lead Blocks

    Directory of Open Access Journals (Sweden)

    Farajollahi A. R.

    2015-06-01

    Full Text Available Introduction: In radiation therapy centers across Iran, protection of normal tissues is usually accomplished by either Cerrobend or lead block shielding. In this study, the influence of these two shielding methods on central axis dose distribution of photon beam a Cobalt unit was investigated in clinical conditions. Materials and Methods: All measurements were performed for 60Co γ-ray beams and the Cerrobend blocks were fabricated by commercial Cerrobend materials. Standard lead block shields belonged to Cobalt unit. Data was collected through a calibrated ionization chamber, relative dosimetry systems and a TLD dosimetery. Results: Results of the percent depth dose (PDD measurements at depths of 0.5, 1, 5, 10, 15 and 20 cm for 23 different field sizes of patients with head and neck cancer showed no significant differences between lead and Cerrobend shielding methods. Measurement results of absolute dosimetry in depths of 1.5, 3, 5, 7, 10 and 12 cm also showed no significant differences between these two shielding methods. The same results were obtained by TLD dosimetry on patient skin. Conclusion: Use of melt shielding methods is a very easy and fast shield-making technique with no differences in PDD, absolute and skin dose between lead and Cerrobend block shielding methods.

  11. Comparison of serum lead level in oral opium addicts with healthy control group.

    Science.gov (United States)

    Salehi, Hossein; Sayadi, Ahmad Reza; Tashakori, Mahnaz; Yazdandoost, Rokhsareh; Soltanpoor, Narges; Sadeghi, Hossein; Aghaee-Afshar, Mahmood

    2009-11-01

    Drug abuse and its consequences are major health problems in Middle-East countries such as Iran. Salesmen and smugglers may add lead to opium during the process of opium preparation to increase the weight of opium for more profit. Several reports have found lead poisoning symptoms in opium addicted patients and there are many nonspecific symptoms mimicking lead poisoning in opium addicted patients. As far as the literature review is concerned, there is no comparative study about blood lead level (BLL) in addicted patients with healthy controls. Therefore, it seems evaluation of blood lead level in opium addicted patients to be important. In this study, the BLL of forty-four subjects in two patient and control groups was evaluated. The patient group (22 subjects) was comprised of patients who used oral opium. Control group (22 subjects) was matched with the patient group for age and sex, considering inclusion and exclusion criteria with a mean age of 38.8+/-6.7. For blood lead assay, 3 mL of whole blood was obtained from both groups by venipuncture and BLL was assessed immediately using an atomic absorption spectrophotometer. The BLL in patient group had a range of 7.2 to 69.9 g/dL with a mean of 21.9+/-13.2. In the healthy control group, BLL was between 4.1 to 17.4 g/dL with a mean of 8.6+/-3.5. The mean difference of both groups (t=4.56) was statistically significant (Popium ingested (r=0.65, Popium ingestion in the patient group. It would be concluded that opium addicts have an elevated BLL compared to healthy controls. Therefore, screening of blood lead concentration is helpful for opium addicted people especially with non-specific symptoms. In this regard, a similar investigation with a larger sample size of opium addicted patients (including both oral and inhaled) and a control group is suggested to confirm the findings of this research.

  12. Effects of cadmium on chick embryogenesis and some comparisons with lead

    Energy Technology Data Exchange (ETDEWEB)

    King, D W; Chen, D C.C.; Hsu, J L

    1978-07-01

    During the last ten years because of the severity of the problem of pollution and the part that heavy metals play in it we have been doing research on the effects of some heavy metals on chick embryogenesis in order to get a comparative study and to elucidate their mechanisms of action. Experiments were performed using 431 fertilized white Leghorn eggs to study the effect of cadmium on chick embryogenesis. Cadmium acetate at 0.015, 0.030, 0.045, 0.060, 0.12 or 0.24 mg/egg and lead acetate at 0.02, 0.04 or 0.075 mg/egg was injected in ovo on the fourth day of incubation. The embryos were taken out on the 19th day and examined for gross defects. Electrocardiograms were recorded on some embryos. Hemoglobin determinations were done on others. The changes in plasma delta-aminolevulinic acid dehydrase (ALAD) of the embryos due to cadmium and lead acetate were also determined. It was found that the LD50 of cadmium acetate was close to 0.045 mg. The highest incidence of abnormality, 30.9% of the surviving embryos, appeared in the 0.030 mg group although malformed embryos were also found in the 0.015, 0.045 and 0.060 mg groups. The most common malformations occurred in the liver (58%) and the cardiovascular system, with edema totalling over 90%. Lesser abnormalities were observed in the limbs. Lead acetate affected ALAD more than cadmium acetate. There was no significant difference on hemoglobin concentration or EKG between the distilled water control and either the cadmium or lead treated groups. Thus, embryolethality, embryotoxicity, congenital abnormalities and changes in ALAD were all observed in the cadmium-treated chick embryos although lead acetate seemed to inhibit the ALAD activity more effectively than cadmium acetate.

  13. Electrophysiological performance of a bipolar membrane-coated titanium nitride electrode: a randomized comparison of steroid and nonsteroid lead designs.

    Science.gov (United States)

    Wiegand, U K; Zhdanov, A; Stammwitz, E; Crozier, I; Claessens, R J; Meier, J; Bos, R J; Bode, F; Potratz, J

    1999-06-01

    The aim of this multicenter study was to investigate the performance of a new cardiac pacemaker lead with a titanium nitride cathode coated with a copolymer membrane. In particular, the electrophysiological effect of steroid dissolved in this ion-exchange membrane was evaluated by randomized comparison. Ninety-five patients were randomized either to the 1450 T (n = 51) or the 1451 T ventricular lead (n = 45) and received telemeteral VVI(R) pacemakers with identical diagnostic features. Both leads were bipolar, were passively affixed, and had a porous titanium nitride tip with a surface area of 3.5 mm2. The only difference between the two electrodes was 13 micrograms of dexamethasone added to the 1450 Ts membrane coating. Voltage thresholds (VTH) at pulse durations of 0.25, 0.37, and 0.5 ms, lead impedance, and sensing thresholds were measured at discharge, 2 weeks, 1 month, 3 months, and 6 months after implantation. Mean amplitude and the slew rate from three telemetered intracardiac electrograms, chronaxie-rheobase product, and minimum energy consumption were calculated. After a 6-month follow-up, mean voltage thresholds of 0.65 +/- 0.20 V and 0.63 +/- 0.34 were achieved for the 1450 T lead and 1451 T lead, respectively. As a result, a VTH < 1.0 V was obtained in all patients with 1450 T electrodes and in 97.7% of patients with 1451 T leads after 6 months follow-up. In both electrodes, stable VTH was reached 2 weeks after implantation, and no transient rise in threshold was observed. No differences were observed between the steroid and the nonsteroid group in respect to VTH, chronaxie-rheobase product, minimum energy consumption, and potential amplitude and slew rate. In conclusion, safe and efficient pacing at low pulse amplitudes were achieved with both leads. The tip design, independently of the steroid additive, prevented any energy-consuming increases in the voltage threshold.

  14. Comparison of lead and sodium-cooled reactors - Safety, fuel cycle performance and some economical aspects

    Energy Technology Data Exchange (ETDEWEB)

    Carlsson, Johan; Tucek, Kamil; Wider, Hartmut [Joint Research Centre, EC-JRC, Westerduinweg 3, P.O. Box 2, NL-0 1755 ZG Petten (Netherlands)

    2006-07-01

    This paper compares the Lead-cooled Fast Reactor (LFR) and the Sodium-cooled Fast Reactor (SFR) regarding different aspects of the coolant, safety and economics. A brief review of design and safety experience of an SFR (BN-600) and some safety philosophy of the most developed LFR (BREST) are presented as well. The pros and cons of the lead and the sodium coolants are discussed. This paper presents results concerning the coolant temperature evolution during three accident scenarios, i.e. Loss-Of- Flow (LOF), Loss-Of-Heat-Sink (LOHS), and Total-Loss-Of-Power (TLOP). It also studies possible moderators, like BeO and hydrides, for the core designs to have negative reactivity feedbacks and favorable reactivity swings. LFR seems to be able to accommodate more minor actinides than SFR at comparable coolant and Doppler feedbacks. We show that LFR can be designed both to breed and burn transuranics from LWRs. The hydrides lead to the most favorable reactivity feedbacks, but the poorest reactivity swing. It is shown that the LFR can handle the LOF transient better than the SFR. This is due to the much lower pressure drop in the LFR core. The coolant outlet temperatures stabilize at 2050 K and 940 K for SFR and LFR, respectively when no feedbacks are considered. Investigations also concern the SFR's performance when the pitch-to-diameter was increased from 1.2 to 1.4. For the LOHS and TLOP accidents their temperature evolutions are milder for the LFR since lead has a 50% larger volumetric heat capacity. For the TLOP the core outlet temperature of the LFR peaks at 1080 K after 2 days. Regarding economics it appears easier to avoid an intermediate cycle in an LFR than an SFR. (authors)

  15. Comparison of lead and sodium-cooled reactors - Safety, fuel cycle performance and some economical aspects

    International Nuclear Information System (INIS)

    Carlsson, Johan; Tucek, Kamil; Wider, Hartmut

    2006-01-01

    This paper compares the Lead-cooled Fast Reactor (LFR) and the Sodium-cooled Fast Reactor (SFR) regarding different aspects of the coolant, safety and economics. A brief review of design and safety experience of an SFR (BN-600) and some safety philosophy of the most developed LFR (BREST) are presented as well. The pros and cons of the lead and the sodium coolants are discussed. This paper presents results concerning the coolant temperature evolution during three accident scenarios, i.e. Loss-Of- Flow (LOF), Loss-Of-Heat-Sink (LOHS), and Total-Loss-Of-Power (TLOP). It also studies possible moderators, like BeO and hydrides, for the core designs to have negative reactivity feedbacks and favorable reactivity swings. LFR seems to be able to accommodate more minor actinides than SFR at comparable coolant and Doppler feedbacks. We show that LFR can be designed both to breed and burn transuranics from LWRs. The hydrides lead to the most favorable reactivity feedbacks, but the poorest reactivity swing. It is shown that the LFR can handle the LOF transient better than the SFR. This is due to the much lower pressure drop in the LFR core. The coolant outlet temperatures stabilize at 2050 K and 940 K for SFR and LFR, respectively when no feedbacks are considered. Investigations also concern the SFR's performance when the pitch-to-diameter was increased from 1.2 to 1.4. For the LOHS and TLOP accidents their temperature evolutions are milder for the LFR since lead has a 50% larger volumetric heat capacity. For the TLOP the core outlet temperature of the LFR peaks at 1080 K after 2 days. Regarding economics it appears easier to avoid an intermediate cycle in an LFR than an SFR. (authors)

  16. Comparison of the transient behavior of lead-based advanced critical and sub-critical reactors

    International Nuclear Information System (INIS)

    Wang Gang; Gu Zhixing; Wang Zhen; Jin Ming; Bai Yunqing

    2014-01-01

    A lead-based reactor developed by FDS Team is proposed in 2011 and designed to be 10 MW. It is a pool type reactor and the primary coolant is driven by natural circulation. The reactor has two operation modes, which are a lead-based critical fast reactor mode and a lead-based sub-critical reactor mode. The conceptual designs of the two modes are both completed by 2013. In this paper, four transient accidents were simulated for both the critical and sub-critical reactors above by NTC-2D code, which is developed by FDS Team for advanced reactor safety analysis. The four accidents were protected and unprotected loss of heat sink accidents (PLOHS and ULOHS), protected and unprotected transient overpower accidents (PTOP and UTOP). The simulation results of the two reactors were compared and analyzed. The results showed that during PLOHS and PTOP accidents for both the two modes, all the key parameters (core power, fuel, cladding and coolant temperatures in the hottest channel) decreased to very small values after the reactor scrammed, which meant the reactors under the two modes were both safe. For ULOHS, the fuel, cladding and coolant temperatures of the sub-critical reactor increased bigger than those of the critical one. For UTOP, the parameters above of the critical fast reactor were much bigger than those of the sub-critical one. The analysis results showed different safety advantages of the lead-based critical fast and sub-critical reactors during different transient accidents. (author)

  17. Amplificación del Segundo Armónico Mediante el Uso de un Cristal Fotónico Amplificación del Segundo Armónico Mediante el Uso de un Cristal Fotónico

    Directory of Open Access Journals (Sweden)

    G. Cerda-Villicaña

    2012-02-01

    Full Text Available Presentamos evidencia experimental de la generación y amplificación de un haz de segundo armónico en una guía de onda plana de niobato de litio mediante la inscripción de un cristal fotónico unidimensional en dicha guía de onda. La observación fue realizada utilizando un láser de Neodimio-YAG (Nd:YAG en modo continuo (cw así como en amarre de modos, obteniendo pulsos con una potencia promedio por debajo del orden de nanojoules (10-9 J y con duración de 150 picosegundos (10-12 seg. La dispersión geométrica introducida por la estructura de bandas fotónica (PGB para los modos de la guía de onda a la frecuencia fundamental y doblada mejora las condiciones de empalme de fase y por lo tanto aumenta la eficiencia de conversión. We present experimental evidence of enhanced second harmonic generation in planar lithiumniobate waveguides by using a photonic crystal on the waveguide. The enhanced signal was observed by using a Nd: YAG pump laser in both continuous mode (c. w. and mode-locked. This last produced sub-nanojoules (10-9 J average power pulses with 150 picoseconds (10-12 s time duration. Phase matching conditions and the conversion efficiency process were improved because of the geometrical dispersion introduced in waveguide modes inside of the photonic band gap structure (PBG at fundamental and second harmonic frequencies.

  18. Detailed comparison of next-to-leading order predictions for jet photoproduction at HERA.

    Energy Technology Data Exchange (ETDEWEB)

    Harris, B. W.; Klassen, M.; Vossebeld, J.

    1999-06-02

    The precision of new HERA data on jet photoproduction opens up the possibility to discriminate between different models of the photon structure. This requires equally precise theoretical predictions from perturbative QCD calculations. In the past years, next-to-leading order calculations for the photoproduction of jets at HERA have become available. Using the kinematic cuts of recent ZEUS analyses, we compare the predictions of three calculations for different dijet and three-jet distributions. We find that in general all three calculations agree within the statistical accuracy of the Monte Carlo integration yielding reliable theoretical predictions. In certain restricted regions of phase space, the calculations differ by up to 5%.

  19. Experimental lead intoxication in dogs: a comparison of blood lead and urinary delta-aminolevulinic acid following intoxication and chelation therapy.

    Science.gov (United States)

    Green, R A; Selby, L A; Zumwalt, R W

    1978-01-01

    Intravenous lead administration to dogs produced an acute syndrome of lead intoxication charcterized by depression, vomiting, anorexia and weight loss. The effect of chelation therapy with calcium disodium ethylene diamine tetraacetate, penicillamine or both was determined by serially monitoring changes in blood lead and urine delta-aminolevulinic acid. Following therapy, blood lead values were significantly lower in chelated dogs than non-treated lead exposed dogs on days 7 and 10. Urine delta-aminolevulinic acid at day 7 was significantly higher in untreated lead exposed dogs than in other groups. There was no significant difference in blood lead or urine delta-aminolevulinic acid between lead intoxicated dogs which underwent the indicated chelation therapy protocols. There was, however, a trend for higher urinary delta-aminolevulinic acid excretion in those intoxicated dogs undergoing calcium disodium ethylene diamine tetraacetate therapy as opposed to those undergoing penicilamine therapy. There was no significant correlation between blood lead and urinary delta-aminolevulinic acid previous to lead exposure. However, after lead exposure significant correlation was present at days 4, 7, 10 and 14. Certain lead exposed dogs following chelation therapy were noted to have normal blood lead levels but elevated urinary delta-aminolevulinic acid suggesting that blood lead does not always correlate with metabolic effects of lead in the body. Urinary delta-aminolevulinic acid was therefore recommended as an additional laboratory parameter which improved assessment of lead exposure in dogs, particularly in determining adequacy of chelation therapy. PMID:667707

  20. The use of steel and lead shieldings in radiotherapy rooms and its comparison with respect to neutrons doses at patients

    International Nuclear Information System (INIS)

    Silva, M.G.; Rebello, W.F.; Andrade, E.R.; Medeiros, M.P.C.; Mendes, R.M.S.; Braga, K.L.; Gomes, R.G.; Santos, R.F.G.

    2015-01-01

    The NCRP Report No. 151, Structural Shielding Design and Evaluation for Megavoltage X- and Gamma-Ray Radiotherapy Facilities, considers, in shielding calculations for radiotherapy rooms, the use of lead and/or steel to be applied on bunker walls. The NCRP Report calculations were performed foreseeing a better protection of people outside the radiotherapy room. However, contribution of lead and steel to patient dose should be taken into account for radioprotection purposes. This work presents calculations performed by MCNPX code in analyzing the Ambient Dose Equivalent due to neutron, H*(10) n , within a radiotherapy room, in the patients area, considering the use of additional shielding of 1 TVL of lead or 1 TVL of steel, positioned at the inner faces of walls and ceiling of a bunker. The head of the linear accelerator Varian 2100/2300 C/D was modeled working at 18MeV, with 5x5cm 2 , 10x10cm 2 , 20x20cm 2 , 30x30cm 2 and 40x40cm 2 openings for jaws and MLC and operating in eight gantry's angles. This study shows that the use of lead generates an average value of H*(10) n at patients area, 8.02% higher than the expected when using steel. Further studies should be performed based on experimental data for comparison with those from MCNPX simulation.

  1. Comparison of chemical solution deposition systems for the fabrication of lead zirconate titanate thin films

    International Nuclear Information System (INIS)

    Lecarpentier, F.; Daglish, M.; Kemmitt, T.

    2001-01-01

    Ferroelectric thin films of lead zirconate titanate Pb(Zr x Ti 1-x )O 3 (PZT) were prepared from five chemical solution deposition (CSD) systems, namely methoxyethanol, citrate, diol, acetic acid and triethanolamine. Physical characteristics of the solutions, processing parameters and physical and electrical properties of the films were used to assess the relative advantages and disadvantages of the different chemical systems. All the CSD systems decomposed to produce single phase perovskite PZT at temperatures above 650 deg C. Thin film deposition was influenced by the specific characteristics of each system such as wetting on the substrate and viscosity. Distinct precursor effects on the thin film crystallinity and electrical performance were revealed. The diol route yielded films with the highest crystallite size, highest permittivity and lowest loss tangent. The relative permittivity exhibited by films made by the other routes were 25% to 35% lower at equivalent thicknesses. Copyright (2001) The Australian Ceramic Society

  2. Stationary sources of airborne lead: a comparison of emissions data for southern California.

    Science.gov (United States)

    Harris, Allison R; Fifarek, Brian J; Davidson, Cliff I; Blackmon, Rebecca Lankey

    2006-04-01

    Estimates for the air releases of lead from stationary point sources are considered for the South Coast Air Basin of California. We have examined four databases published by U.S. Environmental Protection Agency, the California Air Resources Board, and the South Coast Air Quality Management District. Our analysis indicates that none of the databases includes every emitting facility in the South Coast Air Basin of California and that other discrepancies among the databases exist. Additionally, the data have been analyzed for temporal variation, and some of the California Air Resources Board data are not current. The South Coast Air Quality Management District inventory covers 12 times more facilities in 2001 than in 1996. From this analysis, we conclude that all four of the databases would benefit by sharing data, increasing transparency, analyzing uncertainty, and standardizing emission estimation methods.

  3. Comparison of Inventory Systems with Service, Positive Lead-Time, Loss, and Retrial of Customers

    Directory of Open Access Journals (Sweden)

    A. Krishnamoorthy

    2007-01-01

    Full Text Available We analyze and compare three (s,S inventory systems with positive service time and retrial of customers. In all of these systems, arrivals of customers form a Poisson process and service times are exponentially distributed. When the inventory level depletes to s due to services, an order of replenishment is placed. The lead-time follows an exponential distribution. In model I, an arriving customer, finding the inventory dry or server busy, proceeds to an orbit with probability γ and is lost forever with probability (1−γ. A retrial customer in the orbit, finding the inventory dry or server busy, returns to the orbit with probability δ and is lost forever with probability (1−δ. In addition to the description in model I, we provide a buffer of varying (finite capacity equal to the current inventory level for model II and another having capacity equal to the maximum inventory level S for model III. In models II and III, an arriving customer, finding the buffer full, proceeds to an orbit with probability γ and is lost forever with probability (1−γ. A retrial customer in the orbit, finding the buffer full, returns to the orbit with probability δ and is lost forever with probability (1−δ. In all these models, the interretrial times are exponentially distributed with linear rate. Using matrix-analytic method, we study these inventory models. Some measures of the system performance in the steady state are derived. A suitable cost function is defined for all three cases and analyzed using graphical illustrations.

  4. A comparison of leading and lagging indicators of safety in naval aviation.

    Science.gov (United States)

    O'Connor, Paul; Cowan, Shawn; Alton, Jeffrey

    2010-07-01

    The purpose of this paper is to examine the results of two different methods of identifying human factors safety concerns in U.S. Naval aviation. In both studies, the information was collected using the Department of Defense Human Factors Analysis and Classification System (DoD-HFACS). In the first study, aviation mishap data (a lagging indictor) was obtained on 47 F/A-18 and 16 H-60 mishaps. In the second study, the responses of 68 squadrons to a survey regarding the human factors issues that they considered to be of the greatest safety concern were examined (a leading indicator). First study results revealed that skill-based errors were the most commonly cited factors for both F/A-18 and H-60 mishaps (70.2% and 81.3%, respectively). More specifically, the most commonly used nanocodes were 'over control/ under control' (27.7% and 56.3%, respectively), 'breakdown in visual scan' (27.7% and 12.5%, respectively), and 'procedural errors' (23.4% and 37.6%, respectively). The second study identified that the main concern of F/A-18 and H-60 aviators was workload and operational tempo (identified by 85% of squadrons). It can be concluded that the nanocodes that were most commonly used to classify the causes of past mishaps were not identified as major concerns by the squadrons who responded to the survey. The findings from these studies emphasize the importance of examining a number of performance metrics to ensure that effective measures are being taken to improve safety.

  5. X-ray protective clothing. Does DIN 6857-1 allow an objective comparison between lead-free and lead-composite materials?

    International Nuclear Information System (INIS)

    Eder, H.; Schlattl, H.; Hoeschen, C.

    2010-01-01

    Purpose: The validity of DIN 6857-1 to establish lead equivalence for protective clothing is evaluated by Monte Carlo simulations and measurements. Materials and Methods: Commercially available protective clothing made of lead, lead-free and lead-composite materials has been tested regarding its protective efficacy. The analysis has been performed on the one hand in accordance with the test conditions described in the manufacturing standard DIN EN 61331-3 and on the other hand following the new DIN 6857-1 standard. Additionally, measurements have been carried out under simulated patient conditions by using an Alderson-Rando phantom. Results: Following DIN EN 61331-3, the lead-free protective clothing achieved the required protective efficacy only at a restricted tube-voltage range. The test according to DIN 6857-1 showed that the protective criteria were fulfilled only by one lead-composite apron, but not by the three lead-free aprons examined. Thus, in order to guarantee the same protection as lead between 50 and 120 kV, the conditions of DIN 6857-1 must be fulfilled. Conclusion: A modification of DIN EN 61331-3 to account for secondary radiation is strongly advised in the case of lead-free materials. In summary, most of the protective lead-free aprons in use should be used with care, particularly for examinations with a high dose. (orig.)

  6. Charmonium production in proton-proton collisions and in collisions of lead nuclei at CERN and comparison with Brookhaven data

    International Nuclear Information System (INIS)

    Topilskaya, N. S.

    2013-01-01

    A review of experimental data on charmoniumproduction that were obtained in fixed-target experiments at the SPS synchrotron and in proton-proton collisions and in collisions of lead nuclei in beams of the Large Hadron Collider (LHC) at CERN (Switzerland) is presented. A comparison with data obtained at the Brookhaven National Laboratory (USA) from experiments at the Relativistic Heavy Ion Collider (RHIC) is performed. Measurement of the suppression of J/ψ-meson production as a possible signal of the production of quark-gluon plasmawas proposed back in 1986 by T. Matsui and H. Satz. An anomalous suppression of J/ψ-meson production was discovered by the NA50 Collaboration at SPS (CERN) in central collisions of lead nuclei at the c.m. collision energy of 158 GeV per nucleon. Data obtained at the c.m. energy of 200 GeV per nucleon in the PHENIX experiment at RHIC indicate that, depending on multiplicity, the suppression of J/ψ-meson production at this energy approximately corresponds to the suppression of J/ψ-meson production in collisions of lead nuclei at the SPS accelerator. Theoretical models that take into account the regeneration of J/ψ mesons describe better RHIC experimental data. The measurement of charmonium production in proton-proton collisions and in collisions of lead nuclei in LHC beams revealed the importance of taking into account the regeneration process. At the LHC energies, it is also necessary to take into account the contribution of B-meson decays. Future measurements of charmonium production at the LHC to a higher statistical precision and over an extended energy region would be of importance for obtaining deeper insight into the mechanism of charmonium production and for studying the properties of matter at high energy density and temperature

  7. Are lead-free hunting rifle bullets as effective at killing wildlife as conventional lead bullets? A comparison based on wound size and morphology

    Energy Technology Data Exchange (ETDEWEB)

    Trinogga, Anna, E-mail: anna_trinogga@gmx.de; Fritsch, Guido; Hofer, Heribert; Krone, Oliver

    2013-01-15

    Fragmentation of the lead core of conventional wildlife hunting rifle bullets causes contamination of the target with lead. The community of scavenger species which feed on carcasses or viscera discarded by hunters are regularly exposed to these lead fragments and may die by acute or chronic lead intoxication, as demonstrated for numerous species such as white-tailed eagles (Haliaeetus albicilla) where it is among the most important sources of mortality. Not only does hunting with conventional ammunition deposit lead in considerable quantities in the environment, it also significantly delays or threatens the recovery of endangered raptor populations. Although lead-free bullets might be considered a suitable alternative that addresses the source of these problems, serious reservations have been expressed as to their ability to quickly and effectively kill a hunted animal. To assess the suitability of lead-free projectiles for hunting practice, the wounding potential of conventional bullets was compared with lead-free bullets under real life hunting conditions. Wound dimensions were regarded as good markers of the projectiles' killing potential. Wound channels in 34 killed wild ungulates were evaluated using computed tomography and post-mortem macroscopical examination. Wound diameters caused by conventional bullets did not differ significantly to those created by lead-free bullets. Similarly, the size of the maximum cross-sectional area of the wound was similar for both bullet types. Injury patterns suggested that all animals died by exsanguination. This study demonstrates that lead-free bullets are equal to conventional hunting bullets in terms of killing effectiveness and thus equally meet the welfare requirements of killing wildlife as painlessly as possible. The widespread introduction and use of lead-free bullets should be encouraged as it prevents environmental contamination with a seriously toxic pollutant and contributes to the conservation of a wide

  8. Are lead-free hunting rifle bullets as effective at killing wildlife as conventional lead bullets? A comparison based on wound size and morphology

    International Nuclear Information System (INIS)

    Trinogga, Anna; Fritsch, Guido; Hofer, Heribert; Krone, Oliver

    2013-01-01

    Fragmentation of the lead core of conventional wildlife hunting rifle bullets causes contamination of the target with lead. The community of scavenger species which feed on carcasses or viscera discarded by hunters are regularly exposed to these lead fragments and may die by acute or chronic lead intoxication, as demonstrated for numerous species such as white-tailed eagles (Haliaeetus albicilla) where it is among the most important sources of mortality. Not only does hunting with conventional ammunition deposit lead in considerable quantities in the environment, it also significantly delays or threatens the recovery of endangered raptor populations. Although lead-free bullets might be considered a suitable alternative that addresses the source of these problems, serious reservations have been expressed as to their ability to quickly and effectively kill a hunted animal. To assess the suitability of lead-free projectiles for hunting practice, the wounding potential of conventional bullets was compared with lead-free bullets under real life hunting conditions. Wound dimensions were regarded as good markers of the projectiles' killing potential. Wound channels in 34 killed wild ungulates were evaluated using computed tomography and post-mortem macroscopical examination. Wound diameters caused by conventional bullets did not differ significantly to those created by lead-free bullets. Similarly, the size of the maximum cross-sectional area of the wound was similar for both bullet types. Injury patterns suggested that all animals died by exsanguination. This study demonstrates that lead-free bullets are equal to conventional hunting bullets in terms of killing effectiveness and thus equally meet the welfare requirements of killing wildlife as painlessly as possible. The widespread introduction and use of lead-free bullets should be encouraged as it prevents environmental contamination with a seriously toxic pollutant and contributes to the conservation of a wide variety

  9. Análisis, Síntesis y Aplicación de Circuitos Ópticos Birrefringentes Tipo FIR de Dos Puertos en Celosía con Cristales Líquidos

    OpenAIRE

    Vargas, Salvador; Rodríguez, Jorge; Quintero, Raymond; Méndez, Luis; Hernández, Miguel

    2016-01-01

    Los cristales líquidos los encontramos en gran variedad de equipos a nuestro alrededor. Sus aplicaciones más comunes son de pantallas demostradoras en los equipos tales como calculadoras, televisores o computadoras. Sin embargo, también tienen otras aplicaciones menos conocidas como sensores de temperatura, como elementos de realimentación distribuida en láseres, materiales dieléctricos con permitividades sintonizables, como componentes de relleno en fibras de cristal fotónico con el punto de...

  10. Comparison of two methods for blood lead analysis in cattle: graphite-furnace atomic absorption spectrometry and LeadCare(R) II system.

    Science.gov (United States)

    Bischoff, Karyn; Gaskill, Cynthia; Erb, Hollis N; Ebel, Joseph G; Hillebrandt, Joseph

    2010-09-01

    The current study compared the LeadCare(R) II test kit system with graphite-furnace atomic absorption spectrometry for blood lead (Pb) analysis in 56 cattle accidentally exposed to Pb in the field. Blood Pb concentrations were determined by LeadCare II within 4 hr of collection and after 72 hr of refrigeration. Blood Pb concentrations were determined by atomic absorption spectrometry, and samples that were coagulated (n = 12) were homogenized before analysis. There was strong rank correlation (R(2) = 0.96) between atomic absorption and LeadCare II (within 4 hr of collection), and a conversion formula was determined for values within the observed range (3-91 mcg/dl, although few had values >40 mcg/dl). Median and mean blood pb concentrations for atomic absorption were 7.7 and 15.9 mcg/dl, respectively; for LeadCare II, medians were 5.2 mcg/dl at 4 hr and 4.9 mcg/dl at 72 hr, and means were 12.4 and 11.7, respectively. LeadCare II results at 4 hr strongly correlated with 72 hr results (R(2) = 0.96), but results at 72 hr were lower (P atomic absorption. Although there have been several articles that compared LeadCare with other analytical techniques, all were for the original system, not LeadCare II. The present study indicated that LeadCare II results correlated well with atomic absorption over a wide range of blood Pb concentrations and that refrigerating samples for up to 72 hr before LeadCare II analysis was acceptable for clinical purposes.

  11. Comparison of lead removal behaviors and generation of water-soluble sodium compounds in molten lead glass under a reductive atmosphere

    Science.gov (United States)

    Okada, Takashi; Nishimura, Fumihiro; Xu, Zhanglian; Yonezawa, Susumu

    2018-06-01

    We propose a method of reduction-melting at 1000 °C, using a sodium-based flux, to recover lead from cathode-ray tube funnel glass. To recover the added sodium from the treated glass, we combined a reduction-melting process with a subsequent annealing step at 700 °C, generating water-soluble sodium compounds in the molten glass. Using this combined process, this study compares lead removal behavior and the generation of water-soluble sodium compounds (sodium silicates and carbonates) in order to gain fundamental information to enhance the recovery of both lead and sodium. We find that lead removal increases with increasing melting time, whereas the generation efficiency of water-soluble sodium increases and decreases periodically. In particular, near 90% lead removal, the generation of water-soluble sodium compounds decreased sharply, increasing again with the prolongation of melting time. This is due to the different crystallization and phase separation efficiencies of water-soluble sodium in molten glass, whose structure continuously changes with lead removal. Previous studies used a melting time of 60 min in the processes. However, in this study, we observe that a melting time of 180 min enhances the water-soluble sodium generation efficiency.

  12. Combinación de pantallas de cristal líquido para la modulación compleja de frentes de onda. Aplicación en reconstrucción de hologramas de Fresnel digitales.

    OpenAIRE

    Tudela Fernández, Raúl; Martín Badosa, Estela; Labastida i Juan, Ignasi, 1970-; Vallmitjana i Rico, Santiago; Carnicer González, Arturo

    2012-01-01

    En este trabajo se presentan distintas alternativas para obtener la modulación compleja completa de frentes de onda mediante la suma de la modulación introducida por dos pantallas de cristal líquido. Para los distintos métodos se presentan resultados simulados de reconstrucciones de hologramas de Fresnel digitales.

  13. Decay heat removal analyses on the heavy liquid metal cooled fast breeding reactor. Comparisons of the decay heat removal characteristics on lead, lead-bismuth and sodium cooled reactors

    International Nuclear Information System (INIS)

    Sakai, Takaaki; Ohshima, Hiroyuki; Yamaguchi, Akira

    2000-04-01

    The feasibility study on several concepts for the commercial fast breeder reactor(FBR) in future has been conducted in JNC for the kinds of possible coolants and fuel types to confirm the direction of the FBR developments in Japan. In this report, Lead and Lead-Bismuth eutectic coolants were estimated for the decay heat removal characteristics by the comparison with sodium coolant that has excellent features for the heat transfer and heat transport performance. Heavy liquid metal coolants, such as Lead and Lead-Bismuth, have desirable chemical inertness for water and atmosphere. Therefore, there are many economical plant proposals without an intermediate heat transport system that prevents the direct effect on a reactor core by the chemical reaction between water and the liquid metal coolant at the hypocritical tube failure accidents in a steam generator. In this study, transient analyses on the thermal-hydraulics have been performed for the decay heat removal events in Equivalent plant' with the Lead, Lead-Bismuth and Sodium coolant by using Super-COPD code. And a resulted optimized lead cooled plant in feasibility study was also analyzed for the comparison. In conclusion, it is become clear that the natural circulation performance, that has an important roll in passive safety characteristic of the reactor, is more excellent in heavy liquid metals than sodium coolant during the decay heat removal transients. However, we need to confirm the heat transfer reduction by the oxidized film or the corrosion products expected to appear on the heat transfer surface in the Lead and Lead-Bismuth circumstance. (author)

  14. A comparison of the diminution rates of lead in blood and lead mobilized by CaEDTA after termination of occupational exposure: a long-term observation in two lead workers.

    Science.gov (United States)

    Araki, S; Murata, K; Aono, H; Yanagihara, S; Ushio, K

    1983-07-01

    CaEDTA 20 mg/kg was administered weekly for 3.5 years after termination of occupational exposure to two lead workers. The diminution half-lives for lead in blood and urine lead mobilized by CaEDTA were 4.8 and 3.3 years respectively for subject 1 following 28 years exposure and 3.3 and 2.0 years respectively for subject 2 following 26 years exposure. The difference in the diminution rate between lead in blood and lead mobilized by CaEDTA was significant in subject 2 (p less than 0.05).

  15. Contributions to the qualification of the ''CRISTAL'' criticality calculi scheme: interpretation of critical experiments. Elaboration of a characterization system of neutronic configurations

    International Nuclear Information System (INIS)

    Gagnier, E.

    1999-06-01

    This thesis work is about the validation of the new criticality-safety package CRISTAL and contributes to the modernization and the improvement of the computational tools. The first part presents neutronic elements, the objectives of safety criticality studies and the package CRISTAL. Then, the validation work concerned two series of experiments involving uranyl solutions (UO 2 F 2 ) and UO 2 powders. For these experiments, the differences between the computation results and the experimental results were analysed. It was highlighted interesting physical phenomena such of the compensations of errors between the approximate representation by the 99 energy group structure on the first resonance of oxygen and the anisotropy of the diffusion simulation as well as the influence of uranium 234 in high enriched solutions in uranium 235. Once the work of the experimental qualification carried out, raises the question of the use the base of qualification and the ''calculation-experiment'' variations which are referred to it. It is often difficult to establish the link between the ''studied configuration'' and the experiments of the base of qualification. The presented characterisation system proposes to answer in a way automatic and quantified this difficulty: - in bringing an answer on the package qualification for the studied configuration, - in giving an estimate of the package bias. To answer these points, it was defined a set of 35 characteristic neutronic parameters representing the behaviour of the medium. To process the information brought by these parameters and to use it to answer the objectives of the system, we called upon statistical methods (Principal Components Analysis and Sliced Inverse Regression). The results obtained in the feasibility studies showed the relevance of these methods for the considered objectives. (author)

  16. Leading men

    DEFF Research Database (Denmark)

    Bekker-Nielsen, Tønnes

    2016-01-01

    Through a systematic comparison of c. 50 careers leading to the koinarchate or high priesthood of Asia, Bithynia, Galatia, Lycia, Macedonia and coastal Pontus, as described in funeral or honorary inscriptions of individual koinarchs, it is possible to identify common denominators but also disting...

  17. A comparison of the effect of lead nitrate on rat liver chromatin, DNA and histone proteins in solution.

    Science.gov (United States)

    Rabbani-Chadegani, Azra; Abdosamadi, Sayeh; Fani, Nesa; Mohammadian, Shayesteh

    2009-06-01

    Although lead is widely recognized as a toxic substance in the environment and directly damage DNA, no studies are available on lead interaction with chromatin and histone proteins. In this work, we have examined the effect of lead nitrate on EDTA-soluble chromatin (SE chromatin), DNA and histones in solution using absorption and fluorescence spectroscopy, thermal denaturation and gel electrophoresis techniques. The results demonstrate that lead nitrate binds with higher affinity to chromatin than to DNA and produces an insoluble complex as monitored at 400 nm. Binding of lead to DNA decreases its Tm, increases its fluorescence intensity and exhibits hypochromicity at 210 nm which reveal that both DNA bases and the backbone participate in the lead-DNA interaction. Lead also binds strongly to histone proteins in the absence of DNA. The results suggest that although lead destabilizes DNA structure, in the chromatin, the binding of lead introduces some sort of compaction and aggregation, and the histone proteins play a key role in this aspect. This chromatin condensation, upon lead exposure, in turn may decrease fidelity of DNA, and inhibits DNA and RNA synthesis, the process that introduces lead toxicity at the chromatin level.

  18. A comparison of the prevalence of lead-contaminated imported Chinese ceramic dinnerware purchased inside versus outside Philadelphia's Chinatown.

    Science.gov (United States)

    Gilmore, Thomas; O'Malley, Gerald F; Lau, Wayne Bond; Vann, David R; Bromberg, Adam; Martin, Aaron; Gibbons, Andrea; Rimmer, Evan

    2013-03-01

    Lead-contaminated ceramics can be a clinically significant source of lead poisoning, with the potential to cause illness in children and adults; one death in a child has been described. We hypothesized that the prevalence of lead-contaminated ceramics would be higher within Chinatown versus outside of Chinatown. The study was a prospective observational cross-sectional study. Two areas were defined geographically as being within and outside of Philadelphia's Chinatown, and a predefined number of items were purchased in each area. Each item was screened for lead utilizing a colorimetric testing swab. Positive items were leached for lead using the ASTM C738-94 protocol for lead level quantification. The primary outcome was the prevalence of ceramics not compliant with the FDA standard for leachable lead within and outside of Philadelphia's Chinatown. A total of 132 items were purchased, 46 outside of and 86 within Chinatown. More lead-positive items originated within Chinatown than outside of Chinatown [five positive items, 5.8 % prevalence within Chinatown (95 % confidence interval, CI, 2.5-12.9 %), and zero positive, 0 % prevalence outside of Chinatown (95 % CI 0-7.5 %)]. However, this difference was not found to be statistically significant (P = 0.1624). The leachable lead-positive items were up to 40-fold the acceptable FDA levels. Testing a larger number of items may demonstrate a significant source of lead exposure.

  19. A comparison of portable XRF and ICP-OES analysis for lead on air filter samples from a lead ore concentrator mill and a lead-acid battery recycler.

    Science.gov (United States)

    Harper, Martin; Pacolay, Bruce; Hintz, Patrick; Andrew, Michael E

    2006-03-01

    Personal and area samples for airborne lead were taken at a lead mine concentrator mill, and at a lead-acid battery recycler. Lead is mined as its sulfidic ore, galena, which is often associated with zinc and silver. The ore typically is concentrated, and partially separated, on site by crushing and differential froth flotation of the ore minerals before being sent to a primary smelter. Besides lead, zinc and iron are also present in the airborne dusts, together with insignificant levels of copper and silver, and, in one area, manganese. The disposal of used lead-acid batteries presents environmental issues, and is also a waste of recoverable materials. Recycling operations allow for the recovery of lead, which can then be sold back to battery manufacturers to form a closed loop. At the recycling facility lead is the chief airborne metal, together with minor antimony and tin, but several other metals are generally present in much smaller quantities, including copper, chromium, manganese and cadmium. Samplers used in these studies included the closed-face 37 mm filter cassette (the current US standard method for lead sampling), the 37 mm GSP or "cone" sampler, the 25 mm Institute of Occupational Medicine (IOM) inhalable sampler, the 25 mm Button sampler, and the open-face 25 mm cassette. Mixed cellulose-ester filters were used in all samplers. The filters were analyzed after sampling for their content of the various metals, particularly lead, that could be analyzed by the specific portable X-ray fluorescence (XRF) analyzer under study, and then were extracted with acid and analyzed by inductively coupled plasma optical emission spectroscopy (ICP-OES). The 25 mm filters were analyzed using a single XRF reading, while three readings on different parts of the filter were taken from the 37 mm filters. For lead at the mine concentrate mill, all five samplers gave good correlations (r2 > 0.96) between the two analytical methods over the entire range of found lead mass

  20. Comparison and analysis of the efficiency of heat exchange of copper rod and copper wires current lead

    International Nuclear Information System (INIS)

    Fang, J.; Yu, T.; Li, Z.M.; Wei, B.; Qiu, M.; Zhang, H.J.

    2013-01-01

    Highlights: •An optimized design of HTS binary current leads is proposed. •Temperature distributions of two different current leads are calculated. •Experiments are done to certify the calculated temperature distributions. •The experiments proved that the copper wires increase security margins. -- Abstract: Current leads are the key components that connect the low-temperature and high temperature parts of the cryogenic system. Owing to the wide range of temperatures, current leads are the main sources of heat leakage. Since the HTS tapes have no resistance and the generated Joule heat is almost zero, HTS binary current leads can reduce heat leakage compared to the conventional leads. However, heat will still be generated and conducted to the cryogenic system through the copper parts of the HTS current leads. In order to reduce heat leakage by the copper parts of the HTS current leads, this paper presents an optimized design of the copper parts of HTS binary current leads. Inside the leads, the copper wires were applied as an alternative to the copper rod without changing the overall dimensions. Firstly, the differential function of heat transfer was derived. By solving the function, the optimum number of the copper wires and the temperature distribution of two different current leads were gotten. Then the experiment of the temperature distribution was done, and the experimental results were basically the same with the calculative results. The simulation and related experiments proved that the copper wire can increase security margins and reduce maximum temperatures under the same shunt current

  1. Comparison and analysis of the efficiency of heat exchange of copper rod and copper wires current lead

    Energy Technology Data Exchange (ETDEWEB)

    Fang, J., E-mail: fangseer@sina.com [School of Electrical Engineering, Beijing Jiaotong University, Beijing (China); Yu, T. [School of Electrical Engineering, Beijing Jiaotong University, Beijing (China); Li, Z.M.; Wei, B.; Qiu, M.; Zhang, H.J. [China Electric Power Research Institute, Haidian District, Beijing (China)

    2013-11-15

    Highlights: •An optimized design of HTS binary current leads is proposed. •Temperature distributions of two different current leads are calculated. •Experiments are done to certify the calculated temperature distributions. •The experiments proved that the copper wires increase security margins. -- Abstract: Current leads are the key components that connect the low-temperature and high temperature parts of the cryogenic system. Owing to the wide range of temperatures, current leads are the main sources of heat leakage. Since the HTS tapes have no resistance and the generated Joule heat is almost zero, HTS binary current leads can reduce heat leakage compared to the conventional leads. However, heat will still be generated and conducted to the cryogenic system through the copper parts of the HTS current leads. In order to reduce heat leakage by the copper parts of the HTS current leads, this paper presents an optimized design of the copper parts of HTS binary current leads. Inside the leads, the copper wires were applied as an alternative to the copper rod without changing the overall dimensions. Firstly, the differential function of heat transfer was derived. By solving the function, the optimum number of the copper wires and the temperature distribution of two different current leads were gotten. Then the experiment of the temperature distribution was done, and the experimental results were basically the same with the calculative results. The simulation and related experiments proved that the copper wire can increase security margins and reduce maximum temperatures under the same shunt current.

  2. Comparison of lead levels in human permanent teeth from Strasbourg, Mexico City, and rural zones of Alsace

    International Nuclear Information System (INIS)

    Frank, R.M.; Sargentini-Maier, M.L.; Turlot, J.C.; Leroy, M.J.

    1990-01-01

    A comparative study of the mean lead concentrations in enamel and dentin of human premolars and permanent molars was conducted by means of a systematic sampling procedure with energy-dispersive x-ray fluorescence analysis. In a first series of analyses, no significant statistical differences in mean lead concentrations at various levels of enamel and dentin were noted between young patients of Strasbourg and those of small villages of Alsace, nor between elderly patients living in these two locations, despite the fact that motor traffic was significantly lower in the rural zones. However, in both locations, a significantly higher concentration of lead was observed in enamel and dentin in relation to age. In a second series of analyses, the mean lead concentrations of both dental hard tissues of premolars and permanent molars of young individuals from Strasbourg, rural Alsace, and Mexico City were compared. Significantly higher mean lead concentrations were found in enamel and dentin samples from Mexico City. This was most evident for inner coronal dentin (5.7 and 6.1 times greater than in teeth of Strasbourg and rural zones of Alsace, respectively) and for pulpal root dentin (6.9 and 8.9 times greater than in teeth of Strasbourg and rural zones of Alsace). It is proposed that the higher lead concentrations are related to the higher lead content of motor gasoline and to more intense traffic conditions. The dental hard tissues appear to be of value for the study of environmental lead pollution

  3. A comparison of single-lead atrial pacing with dual-chamber pacing in sick sinus syndrome

    DEFF Research Database (Denmark)

    Nielsen, Jens Cosedis; Thomsen, Poul Erik B; Højberg, Søren

    2011-01-01

    In patients with sick sinus syndrome, bradycardia can be treated with a single-lead pacemaker or a dual-chamber pacemaker. Previous trials have revealed that pacing modes preserving atrio-ventricular synchrony are superior to single-lead ventricular pacing, but it remains unclear if there is any ...

  4. Comparison of blood lead levels of mothers and cord blood in intrauterine growth retarded neonates and normal term neonates

    International Nuclear Information System (INIS)

    Iranpour, R.; Besharati, Amir A.; Nasseri, F.; Hashemipour, M.; Kelishadi, R.; Balali-Mood, M.

    2007-01-01

    Objective was to compare the blood lead levels of mothers and cord blood in intrauterine growth retarded (IUGR) neonates and normal term neonates. From April 2005, we carried out a cross-sectional, prospective study in Isfahan University of Medical Sciences, Isfahan, Iran. Blood lead levels were measured in the umbilical cord and maternal venous blood samples in the 32 mother-infant pairs with IUGR full term neonates and 34 mother-infant pairs with normal full term neonates. Blood-lead levels were analyzed by atomic absorption spectrometry. The mean lead concentration in neonates of IUGR and normal groups was not significantly different (107.47+- 16.75 versus 113.08+-19.08 ug/L, p=0.2). The mean lead concentration in mothers of IUGR group was lower than normal groups, but this difference was not significant (124.56+-19.71 versus 135.26+-26.91 ug/L, p=0.07). Maternal lead levels were strongly related with related with cord blood in both IUGR and normal groups (r=0.8, p 100ug/L by the centers for disease control; however, this was not statistically different between the groups. Our results indicate that the mean lead level was not higher in IUGR neonates, and the whole blood lead was not related to the birth weight. In addition, maternal and cord blood lead levels were strongly correlated, and there were remarkable lead burdens on both the mothers and their neonates in this industrial area. (author)

  5. Influencia del tamaño del cristal de cinc de láminas de acero galvanizadas en ambientes que contienen cloruros y sulfatos

    Directory of Open Access Journals (Sweden)

    Julieth Andrea Ramírez-Jerez

    2015-05-01

    Full Text Available El trabajo evaluó la influencia del tamaño del cristal de cinc en el comportamiento electroquímico de láminas de acero galvanizadas por inmersión en caliente. Los ensayos se realizaron en una celda electroquímica plana en soluciones con diferentes concentraciones de NaCl y NaSO4. La velocidad y el mecanismo de corrosión, así como las características resistivas y difusivas de las láminas se evaluaron mediante técnicas electroquímicas, como espectroscopia de impedancia electroquímica (EIS, resistencia a la polarización (Rp y curvas potenciodinámicas. La composición y distribución de los productos de corrosión (FeO y algunos compuestos de cinc y el daño superficial causado por estos se determinaron por medio de DRX y SEM-EDS. Los resultados mostraron que la degradación de la capa de óxidos formada se ve afectada por la presencia de cloruros que penetran, llegan a la superficie del metal base y generan corrosión localizada.

  6. Contributions to the qualification of the ''CRISTAL'' criticality calculi scheme: interpretation of critical experiments. Elaboration of a characterization system of neutronic configurations; Contributions a la qualification du schema de calcul de criticite ''cristal'': interpretation d'experiences critiques. Elaboration d'un systeme de caracterisation des configurations neutroniques

    Energy Technology Data Exchange (ETDEWEB)

    Gagnier, E

    1999-06-01

    This thesis work is about the validation of the new criticality-safety package CRISTAL and contributes to the modernization and the improvement of the computational tools. The first part presents neutronic elements, the objectives of safety criticality studies and the package CRISTAL. Then, the validation work concerned two series of experiments involving uranyl solutions (UO{sub 2}F{sub 2}) and UO{sub 2} powders. For these experiments, the differences between the computation results and the experimental results were analysed. It was highlighted interesting physical phenomena such of the compensations of errors between the approximate representation by the 99 energy group structure on the first resonance of oxygen and the anisotropy of the diffusion simulation as well as the influence of uranium 234 in high enriched solutions in uranium 235. Once the work of the experimental qualification carried out, raises the question of the use the base of qualification and the ''calculation-experiment'' variations which are referred to it. It is often difficult to establish the link between the ''studied configuration'' and the experiments of the base of qualification. The presented characterisation system proposes to answer in a way automatic and quantified this difficulty: - in bringing an answer on the package qualification for the studied configuration, - in giving an estimate of the package bias. To answer these points, it was defined a set of 35 characteristic neutronic parameters representing the behaviour of the medium. To process the information brought by these parameters and to use it to answer the objectives of the system, we called upon statistical methods (Principal Components Analysis and Sliced Inverse Regression). The results obtained in the feasibility studies showed the relevance of these methods for the considered objectives. (author)

  7. Contributions to the qualification of the ''CRISTAL'' criticality calculi scheme: interpretation of critical experiments. Elaboration of a characterization system of neutronic configurations; Contributions a la qualification du schema de calcul de criticite ''cristal'': interpretation d'experiences critiques. Elaboration d'un systeme de caracterisation des configurations neutroniques

    Energy Technology Data Exchange (ETDEWEB)

    Gagnier, E

    1999-06-01

    This thesis work is about the validation of the new criticality-safety package CRISTAL and contributes to the modernization and the improvement of the computational tools. The first part presents neutronic elements, the objectives of safety criticality studies and the package CRISTAL. Then, the validation work concerned two series of experiments involving uranyl solutions (UO{sub 2}F{sub 2}) and UO{sub 2} powders. For these experiments, the differences between the computation results and the experimental results were analysed. It was highlighted interesting physical phenomena such of the compensations of errors between the approximate representation by the 99 energy group structure on the first resonance of oxygen and the anisotropy of the diffusion simulation as well as the influence of uranium 234 in high enriched solutions in uranium 235. Once the work of the experimental qualification carried out, raises the question of the use the base of qualification and the ''calculation-experiment'' variations which are referred to it. It is often difficult to establish the link between the ''studied configuration'' and the experiments of the base of qualification. The presented characterisation system proposes to answer in a way automatic and quantified this difficulty: - in bringing an answer on the package qualification for the studied configuration, - in giving an estimate of the package bias. To answer these points, it was defined a set of 35 characteristic neutronic parameters representing the behaviour of the medium. To process the information brought by these parameters and to use it to answer the objectives of the system, we called upon statistical methods (Principal Components Analysis and Sliced Inverse Regression). The results obtained in the feasibility studies showed the relevance of these methods for the considered objectives. (author)

  8. A comparison of dose savings of lead and lightweight aprons for shielding of 99m-Technetium radiation

    International Nuclear Information System (INIS)

    Warren-Forward, H.; Cardew, P.; Smith, B.; Clack, L.; McWhirter, K.; Johnson, S.; Wessel, K.

    2007-01-01

    Nuclear medicine technologists (NMTs) have the highest effective doses of radiation among medical workers. With increase in the use of lightweight materials in diagnostic radiography, the aim was to compare the effectiveness of lead and lightweight aprons in shielding from 99m-Technetium ( 99m Tc) gamma rays. The doses received from a scattering phantom to the entrance, 9 cm depth and exit of a phantom were measured with LiF:Mg, Cu, P thermoluminescent dosemeters (TLDs). Doses and spectra were assessed without no shielding, with 0.5-mm lead and lightweight aprons. The lead and lightweight aprons decreased entrance surface doses by 76 and 59%, respectively. The spectral analysis showed that the lightweight apron provided better dose reduction at energies 99m Tc labelled radiopharmaceutical. (authors)

  9. SU-E-I-56: Diagnostic Lead Apron Radiation Exposure Comparison Between Manufacture-Stated and Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Syh, J; Patel, B; Syh, J; Song, X; Freund, D; Ding, X; Wu, H [Willis-Knighton Medical Center, Shreveport, LA (United States)

    2015-06-15

    Purpose: Several vendors of diagnostic lead apron used routinely in radiology/fluoroscopy claim to manufacture 0.5 mm lead equivalent shielding. The purpose of this investigation was to address the concern of the weight of lead aprons versus the radiation protection they provide. Methods: Seven diagnostic lead aprons were measured and compared for their radiation transmission and attenuation characteristics. The measurements were performed on a Philips Integris. Two settings were used, normal (76 kVp, 14.3 mA) and high (110 kVp, 12.3 mA) to represent typical patient and large patient thickness. Plastic water was placed on the table to represent patient scatter. A Capintec PM-500 ion chamber was placed at approximate chest height where hospital personnel would stand. An uncovered, i.e. lead-unhindered, ion chamber reading was taken to establish the baseline reading of an unprotected personnel. The ion chamber was then wrapped with 0.5mm 99.9% pure Pb material to establish the measurement reading when a diagnostic lead apron attenuates as adequately as 0.5mm Pb. The lead aprons were measured one at a time with the ion chamber fully covered and enclosed within the aprons. Results: On Normal fluoroscopy setting, the 0.5mm pure Pb showed a transmission of 0.4%. No aprons showed a transmission value as low as 0.5mm Pb. The lowest transmission value measured from the aprons was 2.0%, having a 1.5% higher transmission than pure lead. On High fluoroscopy setting, the lowest apron transmission measurement was at 2.8%, which was comparable to the 0.5mm pure Pb which gave a transmission of 3.0%. Conclusion: At Normal fluoroscopy setting, the 0.5mm Pb provided an attenuation that could not be matched by any apron measured. At High fluoroscopy setting, only one apron exhibited comparable transmission values as 0.5mm pure Pb.

  10. Theoretical and experimental determination of mass attenuation coefficients of lead-based ceramics and their comparison with simulation

    Directory of Open Access Journals (Sweden)

    Vejdani-Noghreiyan Alireza

    2016-01-01

    Full Text Available Mass attenuation coefficient of lead-based ceramics have been measured by experimental methods and compared with theoretical and Monte Carlo simulation results. Lead-based ceramics were prepared using mixed oxide method and the X-ray diffraction analysis was done to evaluate the crystal structure of the produced handmade ceramics. The experimental results show good agreement with theoretical and simulation results. However at two gamma ray energies, small differences between experimental and theoretical results have been observed. By adding other additives to ceramics and observing the changes in the shielding properties such as flexibility, one can synthesize and optimize ceramics as a neutron shield.

  11. SU-E-I-56: Diagnostic Lead Apron Radiation Exposure Comparison Between Manufacture-Stated and Measurements

    International Nuclear Information System (INIS)

    Syh, J; Patel, B; Syh, J; Song, X; Freund, D; Ding, X; Wu, H

    2015-01-01

    Purpose: Several vendors of diagnostic lead apron used routinely in radiology/fluoroscopy claim to manufacture 0.5 mm lead equivalent shielding. The purpose of this investigation was to address the concern of the weight of lead aprons versus the radiation protection they provide. Methods: Seven diagnostic lead aprons were measured and compared for their radiation transmission and attenuation characteristics. The measurements were performed on a Philips Integris. Two settings were used, normal (76 kVp, 14.3 mA) and high (110 kVp, 12.3 mA) to represent typical patient and large patient thickness. Plastic water was placed on the table to represent patient scatter. A Capintec PM-500 ion chamber was placed at approximate chest height where hospital personnel would stand. An uncovered, i.e. lead-unhindered, ion chamber reading was taken to establish the baseline reading of an unprotected personnel. The ion chamber was then wrapped with 0.5mm 99.9% pure Pb material to establish the measurement reading when a diagnostic lead apron attenuates as adequately as 0.5mm Pb. The lead aprons were measured one at a time with the ion chamber fully covered and enclosed within the aprons. Results: On Normal fluoroscopy setting, the 0.5mm pure Pb showed a transmission of 0.4%. No aprons showed a transmission value as low as 0.5mm Pb. The lowest transmission value measured from the aprons was 2.0%, having a 1.5% higher transmission than pure lead. On High fluoroscopy setting, the lowest apron transmission measurement was at 2.8%, which was comparable to the 0.5mm pure Pb which gave a transmission of 3.0%. Conclusion: At Normal fluoroscopy setting, the 0.5mm Pb provided an attenuation that could not be matched by any apron measured. At High fluoroscopy setting, only one apron exhibited comparable transmission values as 0.5mm pure Pb

  12. Song Leading Effectiveness of Undergraduate Education Majors: A Comparison of Student Self Ratings and Expert Ratings under Three Conditions.

    Science.gov (United States)

    Barry, Nancy H.; Orlofsky, Diane DeNicola

    1997-01-01

    Examines the song leading effectiveness of undergraduate education majors under three conditions: unaccompanied, accompanied with autoharp, and accompanied by recording. Finds that students rate themselves higher than experts do; there is greater eye contact using rote or recording; and there is greater tempo accuracy using rote and autoharp. (DSK)

  13. Comparison of a suspended radiation protection system versus standard lead apron for radiation exposure of a simulated interventionalist.

    Science.gov (United States)

    Marichal, Daniel A; Anwar, Temoor; Kirsch, David; Clements, Jessica; Carlson, Luke; Savage, Clare; Rees, Chet R

    2011-04-01

    To evaluate the radiation protective characteristics of a system designed to enhance operator protection while eliminating weight to the body and allowing freedom of motion. Radiation doses to a mock interventionalist were measured with calibrated dosimeters in a clinical interventional suite. A standard lead apron (SLA; Pb equivalent, 0.5 mm) was compared with a suspended radiation protection system (ZeroGravity; Zgrav) that shields from the top of the head to the calves (except the right arm and left forearm) with a complex overhead motion system that eliminates weight on the operator and allows freedom of motion. Zgrav included a suspended lead apron with increased lead equivalency, greater length, proximal left arm and shoulder coverage, and a wraparound face shield of 0.5 mm Pb equivalency. A 26-cm-thick Lucite stack (ie, mock patient) created scatter during 10 controlled angiography sequences of 120 exposures each. Parameters included a field of view of 40 cm, table height of 94 cm, 124 cm from the tube to image intensifier, 50 cm from the image center to operator, 66 kVp, and 466-470 mA. Under identical conditions, average doses (SLA vs Zgrav) were 264 versus 3.4 (ratio, 78) to left axilla (P < .001), 456 versus 10.2 (ratio, 45) to left eye (P < .001), 379.4 versus 6.6 (ratio, 57) to right eye (P < .005), and 18.8 versus 1.2 (ratio, 16) to gonad (P < .001). Relative to a conventional lead apron, the Zgrav system provided a 16-78-fold decrease in radiation exposure for a mock interventionalist in a simulated clinical setting. Copyright © 2011 SIR. Published by Elsevier Inc. All rights reserved.

  14. Comparison of pregnancy rates in PCOS patients undergoing clomiphene citrate and IUI treatment with different leading follicular sizes.

    Science.gov (United States)

    Seckin, Berna; Pekcan, Meryem Kuru; Bostancı, Esra Isci; Inal, Hasan Ali; Cicek, Mahmut Nedim

    2016-04-01

    The objective of the study was to compare the pregnancy rates in PCOS patients undergoing clomiphene citrate (CC) and intrauterine insemination (IUI) treatment with different leading follicular sizes. A total of 358 infertile women with PCOS who underwent 563 clomiphene citrate and IUI treatment cycles were included in this prospective study. Treatment cycles were divided into three groups according to leading follicular size on the day of hCG administration: Group I: follicular size 17-18 mm (n = 177), Group II: 19-22 mm (n = 321), and Group III : >22 mm (n = 65). Pregnancy rates were evaluated. Treatment outcomes of the groups were further analyzed related to endometrial thickness measurement on the day of hCG. For this purpose, cycles were placed into three subgroups as follows: endometrial thickness 9 mm. There was no statistically significant difference in clinical pregnancy rate per cycle between the groups (8.5, 10, and 9.2 % for Group I, II, and III, respectively, p = 0.86). In further analyses related to endometrial thickness, no significant difference was also found in pregnancy rate among the groups. This results suggest that pregnancy rate is not related to leading follicle size on the day of hCG administration in PCOS patients treated with CC and IUI. In addition, pregnancy rate in women with different follicular sizes is not influenced by the endometrial thickness.

  15. Transvenous versus open chest lead placement for resynchronization therapy in patients with heart failure: comparison of ventricular electromechanical synchronicity.

    Science.gov (United States)

    Zhang, Hai-Bo; Meng, Xu; Han, Jie; Li, Yan; Zhang, Ye; Jiang, Teng-Yong; Zhao, Ying-Xin; Zhou, Yu-Jie

    2017-04-01

    Transvenous lead placement is the standard approach for left ventricular (LV) pacing in cardiac resynchronization therapy (CRT), while the open chest access epicardial lead placement is currently the most frequently used second choice. Our study aimed to compare the ventricular electromechanical synchronicity in patients with heart failure after CRT with these two different LV pacing techniques. We enrolled 33 consecutive patients with refractory heart failure secondly to dilated cardiomyopathy who were eligible for CRT in this study. Nineteen patients received transvenous (TV group) while 14 received open chest (OP group) LV lead pacing. Intra- and inter-ventricular electromechanical synchronicity was assessed by tissue Doppler imaging (TDI) before and one year after CRT procedure. Before CRT procedure, the mean QRS-duration, maximum time difference to systolic peak velocity among 12 left ventricle segments (LV Ts-12), standard deviation of time difference to systolic peak velocity of 12 left ventricle segments (LV Ts-SD), and inter-ventricular mechanical delay (IVMD) in OP and TV group were 166 ± 17 ms and 170 ± 21 ms, 391 ± 42 ms and 397 ± 36 ms, 144 ± 30 ms and 148 ± 22 ms, 58 ± 25 ms and 60 ± 36 ms, respectively (all P > 0.05). At one year after the CRT, the mean QRS-duration, LV Ts-12, LV Ts-SD, and IVMD in TV and OP group were 128 ± 14 ms and 141 ± 22 ms ( P = 0.031), 136 ± 37 ms and 294 ± 119 ms ( P = 0.023), 50 ± 22 ms and 96 ± 34 ms ( P = 0.015), 27 ± 11 ms and 27 ± 26 ms ( P = 0.86), respectively. The LV lead implantation procedure time was 53.4 ± 16.3 min for OP group and 136 ± 35.1 min for TV group ( P = 0.016). The mean LV pacing threshold increased significantly from 1.7 ± 0.6 V/0.5 ms to 2.3 ± 1.6 V/0.5 ms ( P open chest access of LV pacing for CRT leads to better improvement of the intraventricular synchronization.

  16. Comparison of lithium and the eutectic lead lithium alloy, two candidate liquid metal breeder materials for self-cooled blankets

    International Nuclear Information System (INIS)

    Malang, S.; Mattas, R.

    1994-06-01

    Liquid metals are attractive candidates for both near-term and long-term fusion applications. The subjects of this comparison are the differences between the two candidate liquid metal breeder materials Li and LiPb for use in breeding blankets in the areas of neutronics, magnetohydrodynamics, tritium control, compatibility with structural materials, heat extraction system, safety, and required R ampersand D program. Both candidates appear to be promising for use in self-cooled breeding blankets which have inherent simplicity with the liquid metal serving as both breeders and coolant. The remaining feasibility question for both breeder materials is the electrical insulation between liquid metal and duct walls. Different ceramic coatings are required for the two breeders, and their crucial issues, namely self-healing of insulator cracks and radiation induced electrical degradation are not yet demonstrated. Each liquid metal breeder has advantages and concerns associated with it, and further development is needed to resolve these concerns

  17. Misure di fenomeni di interazione coerente di protoni a 400 GeV con cristalli curvi per l'LHC

    CERN Document Server

    Rossi, Roberto; Redaelli, Stefano; Scandale, Walter

    A complete analysis of the UA9 H8 data with protons interacting in single pass with crystals had been completed. The analysis is optimized for comparison with simulations routine. Measurements of key crystals properties (bending angle, channeling efficiency, etc.) are performed on the SPS extraction line (H8) with 400 GeV/c protons before testing crystals with circulating beams. A total of 15 crystals had been consistently analyzed in order to compile a comprehensive statistical treatment of different crystals, to identify 'fine' systematic effects (transition region, volume capture, etc. ) and to provide inputs to crystal code developer. Hence we compiled a list of experimental data for the upcoming workshop on crystal simulations, with the analysis results.

  18. Comparison study of photon attenuation characteristics of Lead-Boron Polyethylene by MCNP code, XCOM and experimental data

    Science.gov (United States)

    Zhang, Lei; Jia, Mingchun; Gong, Junjun; Xia, Wenming

    2017-08-01

    The linear attenuation coefficient, mass attenuation coefficient and mean free path of various Lead-Boron Polyethylene (PbBPE) samples which can be used as the photon shielding materials in marine reactor have been simulated using the Monte Carlo N-Particle (MCNP)-5 code. The MCNP simulation results are in good agreement with the XCOM values and the reported experimental data for source Cesium-137 and Cobalt-60. Thus, this method based on MCNP can be used to simulate the photon attenuation characteristics of various types of PbBPE materials.

  19. Comparison of nevirapine plasma concentrations between lead-in and steady-state periods in Chinese HIV-infected patients.

    Directory of Open Access Journals (Sweden)

    Huijuan Kou

    Full Text Available To investigate the potential of nevirapine 200 mg once-daily regimen and evaluate the influence of patient characteristics on nevirapine concentrations.This was a prospective, multicentre cohort study with 532 HIV-infected patients receiving nevirapine as a part of their initial antiretroviral therapy. Plasma samples were collected at trough or peak time at the end of week 2 (lead-in period and week 4, 12, 24, 36, and 48 (steady-state period, and nevirapine concentrations were determined using a validated HPLC method. Potential influencing factors associated with nevirapine concentrations were evaluated using univariate and multivariate logistic regression.A total of 2348 nevirapine plasma concentrations were collected, including 1510 trough and 838 peak values. The median nevirapine trough and peak concentration during the lead-in period were 4.26 µg/mL (IQR 3.05-5.61 and 5.07 µg/mL (IQR 3.92-6.44 respectively, which both exceeded the recommended thresholds of nevirapine plasma concentrations. Baseline hepatic function had a moderate effect on median nevirapine trough concentrations at week 2 (4.25 µg/mL v.s. 4.86 µg/mL, for ALT <1.5 × ULN and ≥ 1.5 × ULN, respectively, P = 0.045. No significant difference was observed in median nevirapine trough concentration between lead-in and steady-state periods in patients with baseline ALT and AST level ≥ 1.5 × ULN (P = 0.171, P = 0.769, which was different from the patients with ALT/AST level <1.5ULN. The median trough concentrations were significantly higher in HIV/HCV co-infected patients than those without HCV at week 48 (8.16 µg/mL v.s. 6.15 µg/mL, P = 0.004.The 200 mg once-daily regimen of nevirapine might be comparable to twice-daily in plasma pharmacokinetics in Chinese population. Hepatic function prior to nevirapine treatment and HIV/HCV coinfection were significantly associated with nevirapine concentrations.

  20. Physical study of the 'snow flake' version of the reactor EL-3 (1963); Etude physique de la version ''cristal de neige'' de la pile EL-3 (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Abillon, E; Genthon, J P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1963-07-01

    A systematic study has been made of the different thermodynamic and neutronic aspects of various versions of the 'snow flake' likely to fulfil the aims which were set out (improvement of the reactivity, of the experimental volume, improvement in the working conditions of EL-3). After this systematic study, a choice was made in principle of one version amongst the several available (solutions using 8 or 10 pencils-various methods of heat transfer: corrugation, cartridges which may or may not be filled with helium... etc., variable enrichments... ). The choice is that of a version which can already at the present be considered as feasible, which represents already a notable improvement of the pile and which does not imply the existence of a major problem as far as the possible change-over later to an improved version is concerned. This choice defines a fuel element and a configuration for the core. A detailed recapitulation has been made of all the research being carried out for the possible solutions in this particular case. (authors) [French] On a etudie systematiquement les differents aspects thermodynamiques et neutroniques de diverses versions 'cristal de neige' susceptibles de remplir les buts fixes (amelioration en reactivite, en volume experimental, amelioration des problemes d'exploitation de EL-3). Apres cette etude systematique, on a procede au choix de principe d'une version parmi les differentes solutions possibles (solutions a 8 ou 10 crayons - possibilite de transfert de chaleur divers: corrugations, cartouches remplies He ou non.... etc., enrichissements variables... ). Ce choix est celui d'une version qu'on peut juger viable des aujourd'hui, qui represente deja une amelioration importante de la pile et qui n'implique pas de probleme majeur quant au passage ulterieur et eventuel a une version plus amelioree. Ce choix definit un element combustible, et une configuration de coeur. On a recapitule et detaille sur ce cas particulier de pile les etudes

  1. Comparison of the leading candidate combinations of blanket materials, thermodynamic cycles, and tritium systems for full scale fusion power plants

    International Nuclear Information System (INIS)

    Fraas, A.P.

    1975-01-01

    The many possible combinations of blanket materials, tritium generation and recovery systems, and power conversion systems were surveyed and a comprehensive set of designs were generated by using a common set of ground rules that include all of the boundary conditions that could be envisioned for a full-scale commercial fusion power plant. Particular attention was given to the effects of blanket temperature on power plant cycle efficiency and economics, the interdependence of the thermodynamic cycle and the tritium recovery system, and to thermal and pressure stresses in the blanket structure. The results indicate that, of the wide variety of systems that have been considered, the most promising employs lithium recirculated in a closed loop within a niobium blanket structure and cooled with boiling potassium or cesium. This approach gives the simplest and lowest cost tritium recovery system, the lowest pressure and thermal stresses, the simplest structure with the lowest probability of a leak, the greatest resistance to damage from a plasma energy dump, and the lowest rate of plasma contamination by either outgassing or sputtering. The only other blanket materials combination that appears fairly likely to give a satisfactory tritium generation and recovery system is a lithium-beryllium fluoride-Incoloy blanket, and even this system involves major uncertainties in the effectiveness, size, and cost of the tritium recovery system. Further, the Li 2 BeF 4 blanket system has the disadvantage that the world reserves of beryllium are too limited to support a full-blown fusion reactor economy, its poor thermal conductivity leads to cooling difficulties and a requirement for a complex structure with intricate cooling passages, and this inherently leads to an expansive blanket with a relatively high probability of leaks. The other blanket materials combinations yield even less attractive systems

  2. A follow-up comparison of blood lead levels between foreign and native workers of battery manufacturing in Taiwan

    International Nuclear Information System (INIS)

    Chuang, H.-Y.; Cheng, W.-C.; Chen, C.-Y.; Yang, Y.-H.; Sung, F.-C.; Yang, C.-Y.; Wu, T.-N.

    2008-01-01

    Foreign workers employed in industries in Taiwan have been found at elevated risk of injuries. Less well known is whether the elevated risk persists in chemical exposure such as lead exposure at battery manufacturing. A cohort of 70 Thai workers and 55 native workers employed at a battery plant were followed up, after an education of job safety, from 2000 until 2002. This study compared the change of blood lead levels (BLLs) between these two groups of workers. With informed consent, BLLs were measured annually for participants and compared. The average baseline BLLs were approximately at similarly high levels between Thai workers and native workers with means ± standard deviations of 36.9 ± 16.4 and 36.2 ± 12.4 μg/dl, respectively (p = 0.79). At the end of 2002, the average concentration was higher in Thai workers than in native workers. Using mixed models, Thai workers had an average of 5.95 μg/dl increase in BLLs over native workers during the 3-year study. Further measurements revealed that the average BLL for workers in the assembly department was 3.57 ± 1.83 μg/dl in excess, compared with workers in the plate engineering department. Thai workers were more likely to drink alcohol but less likely to wear gloves at work and wash hands before meals. The BLL disparities between Thai workers and native workers can partly be explained by differences in risk-taking behaviors. Higher BLLs in Thai workers suggest the need of language appropriate health education to improve their personal hygiene. Workplace smoking ceasing program may be needed both in Thai and native workers

  3. Cardioplegia cristalóide, barotrauma e função endotelial: considerações experimentais Crystalloid cardioplegia, barotrauma and endothelium function: experimental considerations

    Directory of Open Access Journals (Sweden)

    Paulo Roberto B Évora

    1996-06-01

    Full Text Available O presente ensaio experimental estudou o efeito da infusão de solução cardioplégica cristalóide a altas pressões sobre a função endotelial de artérias epicárdicas de cães. Não se encontraram alterações a nível de receptores (curvas dose-respostas à ACH e ADP; da transdução do sinal iniciado nos receptores/sitema de G-proteínas (fluoreto de sódio e nos processos intracelulares da produção de EDRF/ NO (fosfolipase C e ionóforo do cálcio A23187. A função da musculatura lisa vascular não foi afetada quando se analisaram as respostas relaxantes (nitroprussiato de sódio e isoproterenol e contrateis (KCI e prostaglandina 2alfa. Estes achados permitem as seguintes considerrações especulativas: a O barotrauma produzido pela infusão da cardioplegia cristalóide a altas pressões ocorreria apenas em circulações coronarianas previamente doentes? b Uma vez que as infusões duraram de 2 a 3 minutos, seria o barotrauma coronariano um fenômeno dependente do tempo de infusão? c Para que ocorra o barotrauma seriam necessários níveis mais elevados de potássio? d Questionar a existência do fenômeno do barotrauma coronariano produzido pela infusão de soluções cadioplégicas pelo menos nas condições experimentais utilizadas, e A metodologia empregada estuda apenas as reatividades vasculares de artérias coronárias epicárdicas. Estas artérias seriam menos sensíveis aos efeitos da pressão de infusão da cardioplegia do que a microcirculação coronariana? f Seria a circulação coronária do cão menos sensível a altas pressões do que do homem? Estas observações experimentais sugerem que a infusão de cardioplegia cristalóide, moderadamente hipocalêmica, a altas pressõe em um tempo de 2 a 3 minutos, não interfere com a produção de EDRF/NO pelo endotélio de coronárias epicárdicas do cão.Experiments were performed in "organ chambers" to investigate if high pressures infusions of crystalloid cardioplegia

  4. SU-E-T-10: A Dosimetric Comparison of Copper to Lead-Alloy Apertures for Electron Beam Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Rusk, B; Hogstrom, K; Gibbons, J; Carver, R [Mary Bird Perkins Cancer Center, Baton Rouge, LA (United States)

    2014-06-01

    Purpose: To evaluate dosimetric differences of copper compared to conventional lead-alloy apertures for electron beam therapy. Methods: Copper apertures were manufactured by .decimal, Inc. and matching lead-alloy, Cerrobend, apertures were constructed for 32 square field sizes (2×2 – 20×20 cm{sup 2}) for five applicator sizes (6×6–25×25 cm{sup 2}). Percent depth-dose and off-axis-dose profiles were measured using an electron diode in water with copper and Cerrobend apertures for a subset of aperture sizes (6×6, 10×10, 25×25 cm{sup 2}) and energies (6, 12, 20 MeV). Dose outputs were measured for all field size-aperture combinations and available energies (6–20 MeV). Measurements were taken at 100 and 110 cm SSDs. Using this data, 2D planar absolute dose distributions were constructed and compared. Passing criteria were ±2% of maximum dose or 1-mm distance-to-agreement for 99% of points. Results: A gamma analysis of the beam dosimetry showed 93 of 96 aperture size, applicator, energy, and SSD combinations passed the 2%/1mm criteria. Failures were found for small field size-large applicator combinations at 20 MeV and 100-cm SSD. Copper apertures showed a decrease in bremsstrahlung production due to copper's lower atomic number compared to Cerrobend (greatest difference was 2.5% at 20 MeV). This effect was most prominent at the highest energies with large amounts of shielding material present (small field size-large applicator). Also, an increase in electrons scattered from the collimator edge of copper compared to Cerrobend resulted in an increased dose at the field edge for copper at shallow depths (greatest increase was 1% at 20 MeV). Conclusion: Apertures for field sizes ≥6×6 cm{sup 2} at any energy, or for small fields (≤4×4 cm{sup 2}) at energies <20 MeV, showed dosimetric differences less than 2%/1mm for more than 99% of points. All field size-applicator size-energy combinations passed 3%/1mm criteria for 100% of points. Work partially

  5. Characterization of cytoplasmic male sterility of rice with Lead Rice cytoplasm in comparison with that with Chinsurah Boro II cytoplasm.

    Science.gov (United States)

    Itabashi, Etsuko; Kazama, Tomohiko; Toriyama, Kinya

    2009-02-01

    Rice with LD-type cytoplasmic male sterility (CMS) possesses the cytoplasm of 'Lead Rice' and its fertility is recovered by a nuclear fertility restorer gene Rf1. Rf1 promotes processing of a CMS-associated mitochondrial RNA of atp6-orf79, which consists of atp6 and orf79, in BT-CMS with the cytoplasm of 'Chinsurah Boro II'. In this study, we found that LD-cytoplasm contained a sequence variant of orf79 downstream of atp6. Northern blot analysis showed that atp6-orf79 RNA of LD-cytoplasm was co-transcribed and was processed in the presence of Rf1 in the same manner as in BT-cytoplasm. Western blot analysis showed that the ORF79 peptide did not accumulate in an LD-CMS line, while ORF79 accumulated in a BT-CMS line and was diminished by Rf1. These results suggest that accumulation of ORF79 is not the cause of CMS in LD-cytoplasm and the mechanism of male-sterility induction/fertility restoration in LD-CMS is different from that in BT-CMS.

  6. Transfer of lead (Pb) in the soil-plant-mealybug-ladybird beetle food chain, a comparison between two host plants.

    Science.gov (United States)

    Zhang, Can; Wang, Xingmin; Ashraf, Umair; Qiu, Baoli; Ali, Shaukat

    2017-09-01

    Contamination of soil with heavy metals has become an issue of concern on global scale. This study investigates the translocation of lead (Pb) along the soil - plant (eggplant and tomato) - mealybug (Dysmicoccus neobrevipes) - ladybird beetle (Cryptolaemus montrouzieri) food chain. Soil amendments used for this study were adjusted to 0, 25, 50 and 100mg/kg of Pb (w/w). The results revealed significantly higher transfer of Pb in tomato when compared to eggplant. Bio-magnification of Pb (2-4 times) was observed for soil - root transfer whereas Pb was bio-minimized in later part of food chain (shoot - mealybug - ladybird transfer). A dose dependent increase in transfer of Pb across the multi-trophic food chain was observed for both host plants. A decrease in coefficients of Pb transfer (from root - shoot and shoot - mealybug) was observed with increase in Pb concentrations. Our results also showed removal of Pb from the bodies of ladybird beetle during metamorphosis. Further studies are required to explain the mechanisms or physiological pathways involved in the bio-minimization of Pb across the food chain. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. LEADING WITH LEADING INDICATORS

    International Nuclear Information System (INIS)

    PREVETTE, S.S.

    2005-01-01

    This paper documents Fluor Hanford's use of Leading Indicators, management leadership, and statistical methodology in order to improve safe performance of work. By applying these methods, Fluor Hanford achieved a significant reduction in injury rates in 2003 and 2004, and the improvement continues today. The integration of data, leadership, and teamwork pays off with improved safety performance and credibility with the customer. The use of Statistical Process Control, Pareto Charts, and Systems Thinking and their effect on management decisions and employee involvement are discussed. Included are practical examples of choosing leading indicators. A statistically based color coded dashboard presentation system methodology is provided. These tools, management theories and methods, coupled with involved leadership and employee efforts, directly led to significant improvements in worker safety and health, and environmental protection and restoration at one of the nation's largest nuclear cleanup sites

  8. Efecto cristal. Reflexiones sobre arquitectura

    Directory of Open Access Journals (Sweden)

    Dr. Arq. Carlos Pantaleón Panaro

    2017-12-01

    Full Text Available ESPEJISMO es una ilusión óptica debido a la reflexión total de la luz cuando atraviesa capas de aire de densidad distinta, con lo cual los objetos lejanos dan una imagen invertida, como si se reflejaran sobre el agua, tal como ocurre en las llanuras de los desiertos. 1 La definición de espejismo nos explica que es una ilusión, una ficción, un desvarío, un delirio. Algo que no es real ni verdadero, la apariencia engañosa de algo que no existe. ¿Pero no existe, realmente? Tal vez se pueda decir, desde algún punto de vista, que una imagen ilusoria no es real. Pero ¿podríamos afirmarlo desde el punto de vista del fenómeno de la percepción? Si lo vemos, ¿no tendríamos derecho a decir que es real? ¿Algo tiene que ser material y poder tocarse, para ser real? ¿No basta simplemente con verlo? Este artículo de reflexión trata sobre el tema de lo ilusorio, de los espejismos y apariencias engañosas que, no obstante su naturaleza falaz, existen y se perciben, y son procesados por nuestra mente como fenómenos sensoriales que conforman nuestra percepción. El hilo conductor es un viaje a través de diferentes paisajes espejados: el del azar, el de las artes y el de la arquitectura. 1Diccionario de la Real Academia Española

  9. Lead poisoning

    Science.gov (United States)

    ... drinking water in homes containing pipes that were connected with lead solder . Although new building codes require ... lead in their bodies when they put lead objects in their mouths, especially if they swallow those ...

  10. Lead Poisoning

    Science.gov (United States)

    Lead is a metal that occurs naturally in the earth's crust. Lead can be found in all parts of our ... from human activities such as mining and manufacturing. Lead used to be in paint; older houses may ...

  11. Calculo de funciones de onda lcao para el estado fundamental de solidos. aplicación al estudio teórico de la estructura de los cristales de litio y de nitruro de boro. I.

    Directory of Open Access Journals (Sweden)

    Nepomuceno Quitian C.

    2009-07-01

    Full Text Available En esta primera publicación se ha aplicado el formulismo de la Química Cuántica del Estado Sólido, al estudio teórico de los cristales de Litio y de Nitruro de Boro, utilizando una base de funciones Gausianas dentro del método LCAO— SCF—MO (Linear Combination of Atomic Orbitals- Self Consistent Fields – Molecular Orbltals. Se calculan los factores de estructura teóricos a partir de los elementos de la matriz de densidad y las integrales de recubrimiento Generalizadas. Se calcula igualmente la densidad electrónica y una función delta (A a partir de los factores de estructura teóricos, con el fin de poner en evidencia la unión Química.

  12. Comparison between lead levels in dandelions grown in an ultra-clean lab environment (baseline) and those collected from the San Francisco Bay Area

    Science.gov (United States)

    Rojero, J.; Odigie, K. O.; Hibdon, S.; Flegal, A. R.

    2011-12-01

    This study is aimed at establishing the baseline (natural) levels of lead in dandelions (Taraxacum officinale) grown in an ultra-clean environment. Dandelions have been used extensively as biomonitors of environmental lead levels since their distribution is global and they can be easily collected. However, industrial lead contamination is so pervasive that even dandelions from the most remote areas in the world may be contaminated with industrial lead. Therefore, this work will test the hypothesis that "natural" lead levels in dandelions are lower than any previously published values - by growing them in a HEPA filtered air (Class 100) trace metal clean room with high purity (18 MΩ cm) water. Concentrations and isotopic compositions of lead in the clean-room grown dandelions will be compared to values in literature and to those of lead in dandelions collected from San Francisco Bay Area. Lead is a dense, ductile, and highly malleable metal that is found naturally in our environment. Due to its properties it is currently highly used in building construction, in ceramic glazes, lead chromate and in PVC plastic used to coat electrical cords. The uses of lead have included paint, leather tanning, and being used as an additive to gasoline prior to the mid 1970's, as well as others. Due to its many uses, humans are susceptible to lead regularly through various means of exposure from air, water and soil, often leading to lead toxicity.

  13. Lead poisoning

    Energy Technology Data Exchange (ETDEWEB)

    Beijers, J A

    1952-01-01

    Three cases of acute lead poisoning of cattle herds via ingestion are reported, and reference is made to several other incidents of lead in both humans and animals. The quantity of lead which was found in the livers of the dead cows varied from 6.5 to 19 mg/kg, while 1160 mg/kg of lead in the liver was found for a young cow which was poisoned experimentally with 5 gms of lead acetate per day; hence, there appears to be great variability in the amounts deposited that can lead to intoxication and death. No evidence was found for a lead seam around the teeth, prophyrinuria, or basophil granules in the erythrocytes during acute or chronic lead poisoning of cattle or horses examined. Reference is made to attempts of finding the boundary line between increased lead absorption and lead intoxication in humans, and an examination of 60 laborers in an offset-printing office containing a great deal of inhalable lead (0.16 to 1.9 mg/cu m air) is reviewed. Physical deviation, basophylic granulation of erythrocytes, increased lead content of the urine, and porphyrinuria only indicate an increased absorption of lead; the use of the term intoxication is justified if, in addition, there are complaints of lack of appetite, constipation, fatigue, abdominal pain, and emaciation.

  14. Lead Toxicity

    Science.gov (United States)

    ... o Do not use glazed ceramics, home remedies, cosmetics, or leaded-crystal glassware unless you know that they are lead safe. o If you live near an industry, mine, or waste site that may have contaminated ...

  15. Relational Leading

    DEFF Research Database (Denmark)

    Larsen, Mette Vinther; Rasmussen, Jørgen Gulddahl

    2015-01-01

    This first chapter presents the exploratory and curious approach to leading as relational processes – an approach that pervades the entire book. We explore leading from a perspective that emphasises the unpredictable challenges and triviality of everyday life, which we consider an interesting......, relevant and realistic way to examine leading. The chapter brings up a number of concepts and contexts as formulated by researchers within the field, and in this way seeks to construct a first understanding of relational leading....

  16. Lead Test

    Science.gov (United States)

    ... to do renovation and repair projects using lead-safe work practices to avoid creating more lead dust or ... in a dangerous area? Yes. If you are working in a potentially harmful environment with exposure to lead dust or fumes: Wash ...

  17. Toxicity of lead (Pb) to freshwater green algae: Development and validation of a bioavailability model and inter-species sensitivity comparison

    Energy Technology Data Exchange (ETDEWEB)

    De Schamphelaere, K.A.C., E-mail: karel.deschamphelaere@ugent.be; Nys, C., E-mail: chnys.nys@ugent.be; Janssen, C.R., E-mail: colin.janssen@ugent.be

    2014-10-15

    Highlights: • Chronic toxicity of Pb varied 4-fold among three algae species. • The use of an organic P avoided Pb precipitation in the experiments. • pH and Dissolved Organic Carbon strongly affect Pb toxicity, Ca and Mg do not. • A bioavailability model was developed that accurately predicts toxicity. • Algae may become the most sensitive species to Pb above pH 7.4. - Abstract: Scientifically sound risk assessment and derivation of environmental quality standards for lead (Pb) in the freshwater environment are hampered by insufficient data on chronic toxicity and bioavailability to unicellular green algae. Here, we first performed comparative chronic (72-h) toxicity tests with three algal species in medium at pH 6, containing 4 mg fulvic acid (FA)/L and containing organic phosphorous (P), i.e. glycerol-2-phosphate, instead of PO{sub 4}{sup 3−} to prevent lead-phosphate mineral precipitation. Pseudokirchneriella subcapitata was 4-fold more sensitive to Pb than Chlorella kesslerii, with Chlamydomonas reinhardtii in the middle. The influence of medium physico-chemistry was therefore investigated in detail with P. subcapitata. In synthetic test media, higher concentrations of fulvic acid or lower pH protected against toxicity of (filtered) Pb to P. subcapitata, while effects of increased Ca or Mg on Pb toxicity were less clear. When toxicity was expressed on a free Pb{sup 2+} ion activity basis, a log-linear, 260-fold increase of toxicity was observed between pH 6.0 and 7.6. Effects of fulvic acid were calculated to be much more limited (1.9-fold) and were probably even non-existent (depending on the affinity constant for Pb binding to fulvic acid that was used for calculating speciation). A relatively simple bioavailability model, consisting of a log-linear pH effect on Pb{sup 2+} ion toxicity linked to the geochemical speciation model Visual Minteq (with the default NICA-Donnan description of metal and proton binding to fulvic acid), provided relatively

  18. Toxicity of lead (Pb) to freshwater green algae: Development and validation of a bioavailability model and inter-species sensitivity comparison

    International Nuclear Information System (INIS)

    De Schamphelaere, K.A.C.; Nys, C.; Janssen, C.R.

    2014-01-01

    Highlights: • Chronic toxicity of Pb varied 4-fold among three algae species. • The use of an organic P avoided Pb precipitation in the experiments. • pH and Dissolved Organic Carbon strongly affect Pb toxicity, Ca and Mg do not. • A bioavailability model was developed that accurately predicts toxicity. • Algae may become the most sensitive species to Pb above pH 7.4. - Abstract: Scientifically sound risk assessment and derivation of environmental quality standards for lead (Pb) in the freshwater environment are hampered by insufficient data on chronic toxicity and bioavailability to unicellular green algae. Here, we first performed comparative chronic (72-h) toxicity tests with three algal species in medium at pH 6, containing 4 mg fulvic acid (FA)/L and containing organic phosphorous (P), i.e. glycerol-2-phosphate, instead of PO 4 3− to prevent lead-phosphate mineral precipitation. Pseudokirchneriella subcapitata was 4-fold more sensitive to Pb than Chlorella kesslerii, with Chlamydomonas reinhardtii in the middle. The influence of medium physico-chemistry was therefore investigated in detail with P. subcapitata. In synthetic test media, higher concentrations of fulvic acid or lower pH protected against toxicity of (filtered) Pb to P. subcapitata, while effects of increased Ca or Mg on Pb toxicity were less clear. When toxicity was expressed on a free Pb 2+ ion activity basis, a log-linear, 260-fold increase of toxicity was observed between pH 6.0 and 7.6. Effects of fulvic acid were calculated to be much more limited (1.9-fold) and were probably even non-existent (depending on the affinity constant for Pb binding to fulvic acid that was used for calculating speciation). A relatively simple bioavailability model, consisting of a log-linear pH effect on Pb 2+ ion toxicity linked to the geochemical speciation model Visual Minteq (with the default NICA-Donnan description of metal and proton binding to fulvic acid), provided relatively accurate toxicity

  19. Leading Democratically

    Science.gov (United States)

    Brookfield, Stephen

    2010-01-01

    Democracy is the most venerated of American ideas, the one for which wars are fought and people die. So most people would probably agree that leaders should be able to lead well in a democratic society. Yet, genuinely democratic leadership is a relative rarity. Leading democratically means viewing leadership as a function or process, rather than…

  20. Comparison of Deep Brain Stimulation Lead Targeting Accuracy and Procedure Duration between 1.5- and 3-Tesla Interventional Magnetic Resonance Imaging Systems: An Initial 12-Month Experience.

    Science.gov (United States)

    Southwell, Derek G; Narvid, Jared A; Martin, Alastair J; Qasim, Salman E; Starr, Philip A; Larson, Paul S

    2016-01-01

    Interventional magnetic resonance imaging (iMRI) allows deep brain stimulator lead placement under general anesthesia. While the accuracy of lead targeting has been described for iMRI systems utilizing 1.5-tesla magnets, a similar assessment of 3-tesla iMRI procedures has not been performed. To compare targeting accuracy, the number of lead targeting attempts, and surgical duration between procedures performed on 1.5- and 3-tesla iMRI systems. Radial targeting error, the number of targeting attempts, and procedure duration were compared between surgeries performed on 1.5- and 3-tesla iMRI systems (SmartFrame and ClearPoint systems). During the first year of operation of each system, 26 consecutive leads were implanted using the 1.5-tesla system, and 23 consecutive leads were implanted using the 3-tesla system. There was no significant difference in radial error (Mann-Whitney test, p = 0.26), number of lead placements that required multiple targeting attempts (Fisher's exact test, p = 0.59), or bilateral procedure durations between surgeries performed with the two systems (p = 0.15). Accurate DBS lead targeting can be achieved with iMRI systems utilizing either 1.5- or 3-tesla magnets. The use of a 3-tesla magnet, however, offers improved visualization of the target structures and allows comparable accuracy and efficiency of placement at the selected targets. © 2016 S. Karger AG, Basel.

  1. Comparison of some lead and non-lead based glass systems, standard shielding concretes and commercial window glasses in terms of shielding parameters in the energy region of 1 keV-100 GeV: A comparative study

    International Nuclear Information System (INIS)

    Kurudirek, Murat; Ozdemir, Yueksel; Simsek, Onder; Durak, Ridvan

    2010-01-01

    The effective atomic numbers, Z eff of some glass systems with and without Pb have been calculated in the energy region of 1 keV-100 GeV including the K absorption edges of high Z elements present in the glass. Also, these glass systems have been compared with some standard shielding concretes and commercial window glasses in terms of mean free paths and total mass attenuation coefficients in the continuous energy range. Comparisons with experiments were also provided wherever possible for glasses. It has been observed that the glass systems without Pb have higher values of Z eff than that of Pb based glasses at some high energy regions even if they have lower mean atomic numbers than Pb based glasses. When compared with some standard shielding concretes and commercial window glasses, generally it has been shown that the given glass systems have superior properties than concretes and window glasses with respect to the radiation-shielding properties, thus confirming the availability of using these glasses as substitutes for some shielding concretes and commercial window glasses to improve radiation-shielding properties in the continuous energy region.

  2. Leading change.

    Science.gov (United States)

    2017-02-27

    In response to feedback from nursing, midwifery and other care staff who wanted to understand better how the Leading Change, Adding Value framework applies to them, NHS England has updated its webpage to include practice examples.

  3. A comparison on the heat load of HTS current leads with respect to uniform and non-uniform cross-sectional areas

    Energy Technology Data Exchange (ETDEWEB)

    Han, Seung Hak; Nam, Seok Ho; Lee, Je Yull; Song, Seung Hyun; Jeon, Hae Ryong; Baek, Geon Woo; Ko, Tae Kuk [Yonsei University, Seoul (Korea, Republic of); Kang, Hyoung Ku [Korea National University of Transportation, Chungju (Korea, Republic of)

    2017-09-15

    Current lead is a device that connects the power supply and superconducting magnets. High temperature superconductor (HTS) has lower thermal conductivity and higher current density than normal metal. For these reasons, the heat load can be reduced by replacing the normal metal of the current lead with the HTS. Conventional HTS current lead has same cross-sectional area in the axial direction. However, this is over-designed at the cold-end (4.2 K) in terms of current. The heat load can be reduced by reducing this part because the heat load is proportional to the cross-sectional area. Therefore, in this paper, heat load was calculated from the heat diffusion equation of HTS current leads with uniform and non-uniform cross-sectional areas. The cross-sectional area of the warm-end (65K) is designed considering burnout time when cooling system failure occurs. In cold-end, Joule heat and heat load due to current conduction occurs at the same time, so the cross-sectional area where the sum of the two heat is minimum is obtained. As a result of simulation, current leads for KSTAR TF coils with uniform and non-uniform cross-sectional areas were designed, and it was confirmed that the non-uniform cross-sectional areas could further reduce the heat load.

  4. Efeito protetor da criocardioplegia cristalóide na isquemia global e reperfusão durante circulação extracorpórea: um mecanismo dependente do endotélio?

    Directory of Open Access Journals (Sweden)

    ÉVORA Paulo Roberto B

    1997-01-01

    Full Text Available Estudos prévios demonstraram que o comprometimento da produção de EDRF/NO mediada por receptores, após isquemia global e reperfusão, possa ser devido a uma disfunção de G-proteínas que liga os receptores da célula endotelial à via da síntese de EDRF/NO. O presente trabalho experimental sugere que a criocardioplegia cristalóide, associada a hipotermia tópica, previne ou pode reverter, em parte, a disfunção endotelial nas mesmas condições. Mais estudos serão necessários para conclusões mais definitivas, pois as análises estatísticas mais acuradas sugeriram aumento da amostragem. Este detalhe talvez seja devido às grandes dificuldades de uniformização relacionada a este tipo de experimentos. Além disso, demonstrou-se pela primeira vez que a hipotermia, por si só, pode estimular a liberação de EDRF/NO pelo endotélio vascular. Isto sugere que o endotélio possa ser um importante sensor de mudanças da temperatura sangüínea e tem importantes implicações para o entendimento da fisiologia da CEC e dos mecanismos locais de auto-regulação.

  5. Minimum critical values of uranyl and plutonium nitrate solutions calculated by various routes of the french criticality codes system CRISTAL using the new isopiestic nitrate density law

    International Nuclear Information System (INIS)

    Anno, Jacques; Rouyer, Veronique; Leclaire, Nicolas

    2003-01-01

    This paper provides for various cases of 235 U enrichment or Pu isotopic vectors, and different reflectors, new minimum critical values of uranyl nitrate and plutonium nitrate solutions (H + =0) obtained by the standard IRSN calculation route and the new isopiestic density laws. Comparisons are also made with other more accurate routes showing that the standard one's results are most often conservative and usable for criticality safety assessments. (author)

  6. Comparison between Removal Efficiency of Slag, zeolite, and Conventional media in slow sand Filter for Removal of Lead and Cadmium from Water Resources

    Directory of Open Access Journals (Sweden)

    A Ebrahimi

    2016-03-01

    Full Text Available Introduction: Heavy metals owing to their health hazards and high toxicity in low concentration for human and environment have very concern and attention. Slow sand filter is one of the simple and cost-effective for removal of these pollutants. In this method, media play an important role for removal of pollutant. Therefore, the aim of this study was investigation of different media like slag, zeolite, and conventional media in slow sand filter for removal of lead and cadmium. Methods: In this research there are three beds filter include typical filter bed, slag and zeolite that used in pilot plant for investigation of lead and cadmium removal at three concentration of 0.1T 1 and 10 ppm. Each of filters has an internal diameter of 8 cm and a height of 120 cm with Plexiglas, which have a continuous flow operation. Results: The removal efficiency of turbidity by three typical filter bed, slag, and zeolite with initial turbidity of 13 NTU was 46%, 77%, and 89% respectively. Removal efficiency of lead without turbidity was 70.3%, 79%, and 59.8% respectively for 0.1 ppm lead. For 1 ppm, concentration of lead removal efficiency was 51.8%, 52.7% and 52.6% respectively and for 10 ppm it was 53.4%, 57.8%, and 59.8% respectively. Cadmium removal for these media was 23.4%, 37.5%, and 59.4% respectively at 0.1 ppm cadmium. At 1 ppm of cadmium concentration, it was 37.9%, 45% and 41.3% respectively and at 10 ppm concentration of cadmium it was 68.3%, 68.6% and 67% respectively. Conclusion: Slag and zeolite beds are more efficiently than the conventional sand beds in the slow sand filter, so it can be used instead of the usual sand for removing lead and cadmium from resources water.

  7. Ecotoxicology: Lead

    Science.gov (United States)

    Scheuhammer, A.M.; Beyer, W.N.; Schmitt, C.J.; Jorgensen, Sven Erik; Fath, Brian D.

    2008-01-01

    Lead (Pb) is a naturally occurring metallic element; trace concentrations are found in all environmental media and in all living things. However, certain human activities, especially base metal mining and smelting; combustion of leaded gasoline; the use of Pb in hunting, target shooting, and recreational angling; the use of Pb-based paints; and the uncontrolled disposal of Pb-containing products such as old vehicle batteries and electronic devices have resulted in increased environmental levels of Pb, and have created risks for Pb exposure and toxicity in invertebrates, fish, and wildlife in some ecosystems.

  8. Recent Experiments Leading to the Characterization of the Performance of Portable (He-Ne)/CH4 Lasers: Part I: Results of the 1985 International Comparison BIPM-VNIIFTRI

    Science.gov (United States)

    Felder, R.; Chartier, J.-M.; Domnin, Yu S.; Oboukhov, A. S.; Tatarenkov, V. M.

    1988-01-01

    We analyse the results of beat-frequency measurements made on four (He - Ne)/CH4 lasers. It is found that the lack of reproducibility of the frequency of such standards is linked to the existence of various parameters whose relative influences lead to unpredicted experimental results.

  9. A comparison of the isotopic composition of lead in rainwater, surface vegetation and tree bark at the long-term monitoring site, Glensaugh, Scotland, in 2007

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, John G., E-mail: J.G.Farmer@ed.ac.uk [School of GeoSciences, University of Edinburgh, Edinburgh, EH9 3JN, Scotland (United Kingdom); Eades, Lorna J. [School of Chemistry, University of Edinburgh, Edinburgh EH9 3JJ, Scotland (United Kingdom); Graham, Margaret C.; Cloy, Joanna M. [School of GeoSciences, University of Edinburgh, Edinburgh, EH9 3JN, Scotland (United Kingdom); Bacon, Jeffrey R. [The Macaulay Land Use Research Institute, Craigiebuckler, Aberdeen, AB15 8QH, Scotland (United Kingdom)

    2010-08-01

    The lead concentrations and isotopic ratios ({sup 206}Pb/{sup 207}Pb, {sup 208}Pb/{sup 206}Pb, {sup 208}Pb/{sup 207}Pb) of 31 rainwater (September 2006-December 2007) and 11 surface vegetation (moss, lichen, heather) samples (October 2007) from the rural upland catchment of Glensaugh in northeast Scotland and of nine bark samples (October 2007) from trees, predominantly Scots pine, in or near Glensaugh were determined. The mean {sup 206}Pb/{sup 207}Pb ratios for rainwater in 2006 and 2007 were similar to those previously determined for 2000 to 2003 at Glensaugh, yielding an average mean annual value of 1.151 {+-} 0.005 ({+-} 1 SD) for the period from 2000, when an outright ban on leaded petrol came into force in the UK, to 2007. The mean {sup 206}Pb/{sup 207}Pb ratio (1.146 {+-} 0.004; n = 7) for surface vegetation near the top (430-450 m) of the catchment was not significantly different (Student's t test) from that of rainwater (1.148 {+-} 0.017; n = 24) collected over the 12-month period prior to vegetation sampling, but both were significantly different, at the 0.1% (i.e. p < 0.001) and 1% (p < 0.01) level, respectively, from the corresponding mean value (1.134 {+-} 0.006; n = 9) for the outermost layer of tree bark. When considered in conjunction with similar direct evidence for 2002 and indirect evidence (e.g. grass, atmospheric particulates, dated peat) for recent decades in the Glensaugh area, these findings confirm that the lead isotopic composition of surface vegetation, including that of suitably located moss, reflects that of the atmosphere while that of the outermost layer of Scots pine bark is affected by non-contemporaneous lead. The nature and relative extent of the different contributory sources of lead to the current UK atmosphere in the era of unleaded petrol, however, are presently not well characterised on the basis of lead isotopic measurements.

  10. Diagnostic value of ST-segment deviations during cardiac exercise stress testing: Systematic comparison of different ECG leads and time-points.

    Science.gov (United States)

    Puelacher, Christian; Wagener, Max; Abächerli, Roger; Honegger, Ursina; Lhasam, Nundsin; Schaerli, Nicolas; Prêtre, Gil; Strebel, Ivo; Twerenbold, Raphael; Boeddinghaus, Jasper; Nestelberger, Thomas; Rubini Giménez, Maria; Hillinger, Petra; Wildi, Karin; Sabti, Zaid; Badertscher, Patrick; Cupa, Janosch; Kozhuharov, Nikola; du Fay de Lavallaz, Jeanne; Freese, Michael; Roux, Isabelle; Lohrmann, Jens; Leber, Remo; Osswald, Stefan; Wild, Damian; Zellweger, Michael J; Mueller, Christian; Reichlin, Tobias

    2017-07-01

    Exercise ECG stress testing is the most widely available method for evaluation of patients with suspected myocardial ischemia. Its major limitation is the relatively poor accuracy of ST-segment changes regarding ischemia detection. Little is known about the optimal method to assess ST-deviations. A total of 1558 consecutive patients undergoing bicycle exercise stress myocardial perfusion imaging (MPI) were enrolled. Presence of inducible myocardial ischemia was adjudicated using MPI results. The diagnostic value of ST-deviations for detection of exercise-induced myocardial ischemia was systematically analyzed 1) for each individual lead, 2) at three different intervals after the J-point (J+40ms, J+60ms, J+80ms), and 3) at different time points during the test (baseline, maximal workload, 2min into recovery). Exercise-induced ischemia was detected in 481 (31%) patients. The diagnostic accuracy of ST-deviations was highest at +80ms after the J-point, and at 2min into recovery. At this point, ST-amplitude showed an AUC of 0.63 (95% CI 0.59-0.66) for the best-performing lead I. The combination of ST-amplitude and ST-slope in lead I did not increase the AUC. Lead I reached a sensitivity of 37% and a specificity of 83%, with similar sensitivity to manual ECG analysis (34%, p=0.31) but lower specificity (90%, pST-deviations is highest when evaluated at +80ms after the J-point, and at 2min into recovery. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Who Leads China's Leading Universities?

    Science.gov (United States)

    Huang, Futao

    2017-01-01

    This study attempts to identify the major characteristics of two different groups of institutional leaders in China's leading universities. The study begins with a review of relevant literature and theory. Then, there is a brief introduction to the selection of party secretaries, deputy secretaries, presidents and vice presidents in leading…

  12. Technology-based vs. traditional instruction. A comparison of two methods for teaching the skill of performing a 12-lead ECG.

    Science.gov (United States)

    Jeffries, Pamela R; Woolf, Shirley; Linde, Beverly

    2003-01-01

    The purpose of this study was to compare the effectiveness of an interactive, multimedia CD-ROM with traditional methods of teaching the skill of performing a 12-lead ECG. A randomized pre/posttest experimental design was used. Seventy-seven baccalaureate nursing students in a required, senior-level critical-care course at a large midwestern university were recruited for the study. Two teaching methods were compared. The traditional method included a self-study module, a brief lecture and demonstration by an instructor, and hands-on experience using a plastic manikin and a real 12-lead ECG machine in the learning laboratory. The second method covered the same content using an interactive, multimedia CD-ROM embedded with virtual reality and supplemented with a self-study module. There were no significant (p method, or perception of self-efficacy in performing the skill. Overall results indicated that both groups were satisfied with their instructional method and were similar in their ability to demonstrate the skill correctly on a live, simulated patient. This evaluation study is a beginning step to assess new and potentially more cost-effective teaching methods and their effects on student learning outcomes and behaviors, including the transfer of skill acquisition via a computer simulation to a real patient.

  13. Determination of Cadmium and Lead levels in high consumed rice (Oryza Sativa L. cultivated in Lorestan province and its comparison with national standards

    Directory of Open Access Journals (Sweden)

    roshanak Hedayatifar

    2011-03-01

    Full Text Available Rice is the main food of people in Iran and about 2.4 billion of the world population. Although its cultivation areas are less than wheat but 85% of the total product is used by people. Consumption of rice per person is estimated 42.5 kg in Iran. So it is the second high consumed agricultural product. The aim of this study was determination amount of toxic and heavy metals in high consumed rice varites cultivated in different areas of Lorestan province. Materials and Methods: In this study 99 rice samples (Tarem and Domsiah cultivated in three areas of Lorestan( khorramabad, Dorud and Borujerd province were collected. Amount of Lead and Cadmium were analyzed by atomic absorption model BRAIC WFX 130. Data were gathered and analyzed by SPSS software and compared with national standards. Results: The results for Cd and Pb were 0.037±0.06 and 0.077±0.08 mg/kg respectively. Conclusion: Cadmium and Lead levels in rice samples caltivated in Lorestan province were less than Permissible limit, so there is no risk for human health.

  14. Comparison of mobile apps for the leading causes of death among different income zones: a review of the literature and app stores.

    Science.gov (United States)

    Martínez-Pérez, Borja; de la Torre-Díez, Isabel; López-Coronado, Miguel; Sainz-De-Abajo, Beatriz

    2014-01-09

    The advances achieved in technology, medicine, and communications in the past decades have created an excellent scenario for the improvement and expansion of eHeath and mHealth in particular. Mobile phones, smartphones, and tablets are exceptional means for the application of mobile health, especially for those diseases and health conditions that are the deadliest worldwide. The main aim of this paper was to compare the amount of research and the number of mobile apps dedicated to the diseases and conditions that are the leading causes of death according to the World Health Organization grouped by different income regions. These diseases and conditions were ischemic heart disease; stroke and other cerebrovascular diseases; lower respiratory infections; chronic obstructive pulmonary disease; diarrheal diseases; HIV/AIDS; trachea, bronchus, and lung cancers; malaria; and Alzheimer disease and other dementias. Two reviews were conducted. In the first, the systems IEEE Xplore, Scopus, Web of Knowledge, and PubMed were used to perform a literature review of applications related to the mentioned diseases. The second was developed in the currently most important mobile phone apps stores: Google play, iTunes, BlackBerry World, and Windows Phone Apps+Games. Search queries up to June 2013 located 371 papers and 557 apps related to the leading causes of death, and the following findings were obtained. Alzheimer disease and other dementias are included in the diseases with more apps, although it is not among the top 10 causes of death worldwide, whereas lower respiratory infections, the third leading cause of death, is one of the less researched and with fewer apps. Two diseases that are the first and second of low-income countries (lower respiratory infections and diarrheal diseases) have very little research and few commercial applications. HIV/AIDS, in the top 6 of low-income and middle-income zones, is one of the diseases with more research and applications, although it is

  15. Cadmium, copper, lead, and zinc determination in precipitation: A comparison of inductively coupled plasma atomic emission spectrometry and graphite furnace atomization atomic absorption spectrometry

    Science.gov (United States)

    Reddy, M.M.; Benefiel, M.A.; Claassen, H.C.

    1987-01-01

    Selected trace element analysis for cadmium, copper, lead, and zinc in precipitation samples by inductively coupled plasma atomic emission Spectrometry (ICP) and by atomic absorption spectrometry with graphite furnace atomization (AAGF) have been evaluated. This task was conducted in conjunction with a longterm study of precipitation chemistry at high altitude sites located in remote areas of the southwestern United States. Coefficients of variation and recovery values were determined for a standard reference water sample for all metals examined for both techniques. At concentration levels less than 10 micrograms per liter AAGF analyses exhibited better precision and accuracy than ICP. Both methods appear to offer the potential for cost-effective analysis of trace metal ions in precipitation. ?? 1987 Springer-Verlag.

  16. The significance of lead-210, polonium-210 and protactinium-231 in emissions from coal-fired power stations: a comparison with natural environmental sources

    International Nuclear Information System (INIS)

    Corbett, J.O.

    1981-04-01

    Recently published calculations have suggested that a hypothetical individual may receive an effective radiation dose equivalent of 23 mrem/y from coal-fired power station emissions through the ingestion of lead-210, polonium-210 and protactinium-231. It is shown that the model used in those calculations is over-pessimistic by one or two orders of magnitude when applied to the deposition of Pb-210 and Po-210 derived from the decay of radon naturally present in the atmosphere. A more recent assessment of metabolic data for Pa-231 suggests that estimated doses from this nuclide also can be reduced by about a factor of twenty. It is concluded that the maximum effective dose equivalent from power station emissions probably does not exceed 1-2 mrem/y. (author)

  17. Zinc, copper and lead contents of wines. Comparison between the total concentrations by atomic absorption spectrometry and the concentrations of the free ions by polarography

    Directory of Open Access Journals (Sweden)

    J.-B. Fournier

    1998-03-01

    Full Text Available In the introduction of this article, some examples of the use of trace element data in the characterisation of viticultural produce are reminded. This paper described the determination of zinc, copper and lead by two techniques based on radically different principles. The atomic absorption spectrometry, applied after the mineralisation of the samples by wet process, allows the determination of the total element contents in wine. The polarography allows the analysis of the concentrations of these elements that are under labile chemical forms, and which are dissolved under the ionic forms Zn++, Cu++ and Pb++. The wines analysed in this study were produced from three different parcels chosen in relation to their geological qualities. The vines implanted on these parcels are strictly identical, and three fermentation techniques were applied to each lots of grapes. The results obtained shows that the copper is only under ionic form and that the temperature of the fermentation influences the total copper level in the final wine. At the opposite, there is no ion Pb++ in the samples, but a long duration of maceration increases the lead content. Concerning zinc, only the ions Zn++ are present in the wine in case of a short duration of the maceration. When this duration increases, some other chemical forms of zinc are dissolved in addition to the ions Zn++ which are instantaneously dissociated in aqueous solutions. The problem of the contamination of grapes by the materials used, the phytosanitary treatments and the atmospheric pollution is discussed. The knowledge of the proportion of a trace element that is under ionic forms is indispensable to evaluate the bio-availability of the considered element and the toxicologic risks. The advent and the expansion of the electrochemical methods is expected as an important advance in this field of research.

  18. Metabolism of isoniazid by neutrophil myeloperoxidase leads to isoniazid-NAD(+) adduct formation: A comparison of the reactivity of isoniazid with its known human metabolites.

    Science.gov (United States)

    Khan, Saifur R; Morgan, Andrew G M; Michail, Karim; Srivastava, Nutan; Whittal, Randy M; Aljuhani, Naif; Siraki, Arno G

    2016-04-15

    The formation of isonicotinyl-nicotinamide adenine dinucleotide (INH-NAD(+)) via the mycobacterial catalase-peroxidase enzyme, KatG, has been described as the major component of the mode of action of isoniazid (INH). However, there are numerous human peroxidases that may catalyze this reaction. The role of neutrophil myeloperoxidase (MPO) in INH-NAD(+) adduct formation has never been explored; this is important, as neutrophils are recruited at the site of tuberculosis infection (granuloma) through infected macrophages' cell death signals. In our studies, we showed that neutrophil MPO is capable of INH metabolism using electron paramagnetic resonance (EPR) spin-trapping and UV-Vis spectroscopy. MPO or activated human neutrophils (by phorbol myristate acetate) catalyzed the oxidation of INH and formed several free radical intermediates; the inclusion of superoxide dismutase revealed a carbon-centered radical which is considered to be the reactive metabolite that binds with NAD(+). Other human metabolites, including N-acetyl-INH, N-acetylhydrazine, and hydrazine did not show formation of carbon-centered radicals, and either produced no detectable free radicals, N-centered free radicals, or superoxide, respectively. A comparison of these free radical products indicated that only the carbon-centered radical from INH is reducing in nature, based on UV-Vis measurement of nitroblue tetrazolium reduction. Furthermore, only INH oxidation by MPO led to a new product (λmax=326nm) in the presence of NAD(+). This adduct was confirmed to be isonicotinyl-NAD(+) using LC-MS analysis where the intact adduct was detected (m/z=769). The findings of this study suggest that neutrophil MPO may also play a role in INH pharmacological activity. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. The testing of batteries linked to supercapacitors with electrochemical impedance spectroscopy: A comparison between Li-ion and valve regulated lead acid batteries

    Science.gov (United States)

    Ferg, Ernst; Rossouw, Claire; Loyson, Peter

    2013-03-01

    For electric vehicles, a supercapacitor can be coupled to the electrical system in order to increase and optimize the energy and power densities of the drive system during acceleration and regenerative breaking. This study looked at the charge acceptance and maximum discharge ability of a valve regulated lead acid (VRLA) and a Li-ion battery connected in parallel to supercapacitors. The test procedure evaluated the advantage of using a supercapacitor at a 2 F:1 Ah ratio with the battery types at various states of charge (SoC). The results showed that about 7% of extra charge was achieved over a 5-s test time for a Li-ion hybrid system at 20% SoC, whereas at the 80% SoC the additional capacity was approximately 16%. While for the VRLA battery hybrid system, an additional charge of up to 20% was achieved when the battery was at 80% SoC, with little or no benefit at the 20% SoC. The advantage of the supercapacitor in parallel with a VRLA battery was noticeable on its discharge ability, where significant extra capacity was achieved for short periods of time for a battery at the 60% and 40% SoC when compared to the Li-ion hybrid system. The study also made use of Electrochemical Impedance Spectroscopy (EIS) with a suitable equivalent circuit model to explain, in particular, the internal resistance and capacitance differences observed between the different battery chemistries with and without a supercapacitor.

  20. COMPARISON OF TWO TEMPERATURE MEASUREMENT METHODS BY UPCONVERSION FLUORESCENCE SPECTRA OF ERBIUM-DOPED LEAD-FLUORIDE NANO-GLASS-CERAMICS

    Directory of Open Access Journals (Sweden)

    V. A. Aseev

    2015-05-01

    Full Text Available The study and compare of two temperature measurement methods is performed for the case of a lead-fluoride nano-glassceramics in the range from 317 to 423 K with a view to their application to temperature sensors. A method of temperature measurement by means of violet, green and red upconversion fluorescence spectra regression on latent structures and a method of temperature measurement by two fluorescence bands intensity ratio in green range are considered. It is shown that a four-dimensional space of latent structures is an optimum one in terms of temperature measurement accuracy. It made possible temperature determining with a relative error not larger than 0.15% at temperatures higher than 340 K by making use of fluorescence spectra training set with the step of 10 K. The method using two green bands fluorescence intensity ratio is inferior by the accuracy. Independence of pump power fluctuations is a significant advantage of the second method. To take advantage of the first method a stabilization of the pump power is necessary. The results of the work can be taken into account while developing optical temperature sensors with a better performance (in relation to accuracy and measurement range compared to existing ones which utilize temperature redistribution of fluorescence intensities in two closely-spaced bands or temperature dependence of fluorescence lifetime.

  1. Comparison of Biomass and Lipid Production under Ambient Carbon Dioxide Vigorous Aeration and 3% Carbon Dioxide Condition Among the Lead Candidate Chlorella Strains Screened by Various Photobioreactor Scales

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Naoko [Univ. of Nebraska, Lincoln, NE (United States); Barnes, Austin [Univ. of Nebraska, Lincoln, NE (United States); Jensen, Travis [Univ. of Nebraska, Lincoln, NE (United States); Noel, Eric [Univ. of Nebraska, Lincoln, NE (United States); Andlay, Gunjan [Synaptic Research, Baltimore, MD (United States); Rosenberg, Julian N. [Johns Hopkins Univ., Baltimore, MD (United States); Betenbaugh, Michael J. [Johns Hopkins Univ., Baltimore, MD (United States); Guarnieri, Michael T. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Oyler, George A. [Univ. of Nebraska, Lincoln, NE (United States); Johns Hopkins Univ., Baltimore, MD (United States); Synaptic Research, Baltimore, MD (United States)

    2015-09-01

    Chlorella species from the UTEX collection, classified by rDNA-based phylogenetic analysis, were screened based on biomass and lipid production in different scales and modes of culture. Lead candidate strains of C. sorokiniana UTEX 1230 and C. vulgaris UTEX 395 and 259 were compared between conditions of vigorous aeration with filtered atmospheric air and 3% CO2 shake-flask cultivation. We found that the biomass of UTEX 1230 produced 2 times higher at 652 mg L-1 dry weight under both ambient CO2 vigorous aeration and 3% CO2 conditions, while UTEX 395 and 259 under 3% CO2 increased to 3 times higher at 863 mg L-1 dry weight than ambient CO2 vigorous aeration. The triacylglycerol contents of UTEX 395 and 259 increased more than 30 times to 30% dry weight with 3% CO2, indicating that additional CO2 is essential for both biomass and lipid accumulation in UTEX 395 and 259.

  2. Comparison of electrochemical performance of as-cast Pb-1 wt.% Sn and Pb-1 wt.% Sb alloys for lead-acid battery components

    Energy Technology Data Exchange (ETDEWEB)

    Osorio, Wislei R.; Peixoto, Leandro C.; Garcia, Amauri [Department of Materials Engineering, University of Campinas - UNICAMP, PO Box 612, 13083-970 Campinas, SP (Brazil)

    2010-03-15

    A comparative experimental study of the electrochemical features of as-cast Pb-1 wt.% Sn and Pb-1 wt.% Sb alloys is carried out with a view to applications in the manufacture of lead-acid battery components. The as-cast samples are obtained using a water-cooled unidirectional solidification system. Pb-Sn and Pb-Sb alloy samples having similar coarse cell arrays are subjected to corrosion tests in order to assess the effect of Sn or Sb segregation in the cell boundary on the electrochemical performance. Electrochemical impedance spectroscopy (EIS) diagrams, potentiodynamic polarization curves and an equivalent circuit analysis are used to evaluate the electrochemical parameters in a 0.5 M H{sub 2}SO{sub 4} solution at 25 C. Both the experimental and simulated EIS parameters evidence different kinetics of corrosion. The Pb-1 wt.% Sn alloy is found to have a current density which is of about three times lower than that of the Pb-1 wt.% Sb alloy which indicates that dilute Pb-Sn alloys have higher potential for application as positive grid material in maintenance-free Pb-acid batteries. (author)

  3. Comparison of Iran’s and World’s Leading Faculties Approved Curriculum in the Field of Pharmacy, in terms of Pharmaceutical Care Education

    Directory of Open Access Journals (Sweden)

    Kaveh Eslami

    2018-02-01

    Full Text Available Background: Following the changes in the basic concepts of pharmaceutical science, the main opinion in pharmacy practice changed from “drug-oriented pharmacy” to “patient-oriented pharmacy”, leading to changes in the pharmacy education in many aspects.Methods: In the presented study, we compare Iran’s Pharm.D education system and the four of high ranking systems available in the world in term of pharmaceutical care related educations and how much is the portion of this type educations in the curriculum. The University of California, San Francisco (UCSF with a rank of 2, The University of Michigan with a rank of 7, and the Universities of Pittsburgh and Purdue with ranks of almost under 50 in the world ranking have been selected.Results: The results showed, in the United States (US colleges about 60.5% of educational program was related to the pharmaceutical care concept. This calculation for the University of Waterloo was about 74%. The Saudi University compared, had about 47% related units. Regarding the Iranian program, when the specialized units after basic science were considered as the professional course, about 24% of them had a relationship with the pharmaceutical care. However, this was in the case that a student chooses the hospital internship instead of industry internship in the final year; otherwise, the percentage would reduce to 22.7%.Conclusion: Based on the results of this study, and regarding internationally accepted standards, we strongly recommend to change the structure of pharmacy curriculum in Iran to improve the ability of students for patient-oriented services.

  4. A comparison of lead pollution record in Sphagnum peat with known historical Pb emission rates in the British isles and the Czech Republic

    Energy Technology Data Exchange (ETDEWEB)

    Novak, M.; Erel, Y.; Zemanova, L.; Bottrell, S.H.; Adamova, M. [Czech Geological Survey, Prague (Czech Republic)

    2008-12-15

    Vertical Pb concentration gradients and isotope ratios (Pb-206/Pb-207, Pb-208/Pb-207) are reported for five Pb-210-dated Sphagnum peat profiles. The studied peat bogs are in the British Isles (Thorne Moors, England; Mull, Scotland; and Connemara, Eire) and central Europe (Ocean, northern Czech Republic: Rybarenska slat, southern Czech Republic). Both the U.K. and the Czech Republic experienced maximum Pb emissions from Ag-Pb smelting around 1880. Pb emissions from coal burning peaked in 1955 in the U.K, and in the 1980s in the Czech Republic. In both countries, use of alkyl-lead additives to gasoline resulted in large Pb emissions between 1950 and 2000. We hypothesized that peaks in Pb emissions from smelting, coal burning and gasoline burning, respectively, should be mirrored in the peat profiles. However, a more complicated pattern emerged. Maximum annual Pb accumulation rates occurred in 1870 at Ocean, 1940 at Thorne Moors, 1988 at Rybarenska slat, and 1990 at Mull and Connemara. Atmospheric Pb inputs decreased in the order Thorne Moors {ge} Ocean > Rybarenska slat > Mull > Connemara. The Ocean bog was unique in the central European region in that its maximum Pb pollution dated back to the 19th century and coincided with maximum Pb smelting at Freiberg and Pribram. In contrast, numerous previously studied sites showed no Pb accumulation maximum in the 19th century, but increasing pollution until the 1980s. It remains unclear why Ocean did not record the regional peak in Pb emissions caused by high coal and gasoline burning around 1980, while an array of nearby bogs studied previously did record the 1980 coal/gasoline peak, but no 1880 smelting peak. Mean Pb-206/Pb-207 ratios of potential pollution sources were 1.07 and 1.11 for gasoline, 1.17 and 1.17 for local ores, and 1.18 and 1.19 for coal in the U.K. and the Czech Republic, respectively.

  5. Lead isotopic signatures in Antarctic marine sediment cores: A comparison between 1 M HCl partial extraction and HF total digestion pre-treatments for discerning anthropogenic inputs

    International Nuclear Information System (INIS)

    Townsend, A.T.; Snape, I.; Palmer, A.S.; Seen, A.J.

    2009-01-01

    Sensitive analytical techniques are typically required when dealing with samples from Antarctica as even low concentrations of contaminants can have detrimental environmental effects. Magnetic Sector ICP-MS is an ideal technique for environmental assessment as it offers high sensitivity, multi-element capability and the opportunity to determine isotope ratios. Here we consider the Pb isotope record of five marine sediment cores collected from three sites in the Windmill Islands area of East Antarctica: Brown Bay adjacent to the current Australian station Casey, Wilkes near the abandoned US/Australian Station and McGrady Cove lying midway between the two. Two sediment pre-treatment approaches were considered, namely partial extraction with 1 M HCl and total dissolution involving HF. Lead isotope ratio measurements made following sediment partial extraction provided a more sensitive indication of Pb contamination than either Pb concentrations alone (irrespective of sample pre-treatment method) or isotope ratios made after HF digestion, offering greater opportunity for discrimination between impacted and natural/geogenic samples and sites. Over 90% of the easily extractable Pb from sediments near Casey was anthropogenic in origin, consisting of Pb from major Australian deposits. At Wilkes impact from discarded batteries with a unique isotopic signature was found to be a key source of Pb contamination to the marine environment with ∼ 70-80% of Pb being anthropogenic in origin. The country and source of origin of these batteries remain unknown. Little evidence was found suggesting contamination at Wilkes by Pb originating from the major US source, Missouri. No definitive assessment could be made regarding Pb impact at McGrady Cove as the collected sediment core was of insufficient depth. Although Pb isotope ratio signatures may indicate anthropogenic input, spatial concentration gradients at nearby Brown Bay suggest contamination at McGrady Cove is unlikely. We

  6. A comparison of lead pollution record in Sphagnum peat with known historical Pb emission rates in the British Isles and the Czech Republic

    Science.gov (United States)

    Novak, Martin; Erel, Yigal; Zemanova, Leona; Bottrell, Simon H.; Adamova, Marie

    Vertical Pb concentration gradients and isotope ratios ( 206Pb/ 207Pb, 208Pb/ 207Pb) are reported for five 210Pb-dated Sphagnum peat profiles. The studied peat bogs are in the British Isles (Thorne Moors, England; Mull, Scotland; and Connemara, Eire) and central Europe (Ocean, northern Czech Republic; Rybarenska slat, southern Czech Republic). Both the U.K. and the Czech Republic experienced maximum Pb emissions from Ag-Pb smelting around 1880. Pb emissions from coal burning peaked in 1955 in the U.K. and in the 1980s in the Czech Republic. In both countries, use of alkyl-lead additives to gasoline resulted in large Pb emissions between 1950 and 2000. We hypothesized that peaks in Pb emissions from smelting, coal burning and gasoline burning, respectively, should be mirrored in the peat profiles. However, a more complicated pattern emerged. Maximum annual Pb accumulation rates occurred in 1870 at Ocean, 1940 at Thorne Moors, 1988 at Rybarenska slat, and 1990 at Mull and Connemara. Atmospheric Pb inputs decreased in the order Thorne Moors ≥ Ocean > Rybarenska slat > Mull > Connemara. The Ocean bog was unique in the central European region in that its maximum Pb pollution dated back to the 19th century and coincided with maximum Pb smelting at Freiberg and Pribram. In contrast, numerous previously studied sites showed no Pb accumulation maximum in the 19th century, but increasing pollution until the 1980s. It remains unclear why Ocean did not record the regional peak in Pb emissions caused by high coal and gasoline burning around 1980, while an array of nearby bogs studied previously did record the 1980 coal/gasoline peak, but no 1880 smelting peak. Mean 206Pb/ 207Pb ratios of potential pollution sources were 1.07 and 1.11 for gasoline, 1.17 and 1.17 for local ores, and 1.18 and 1.19 for coal in the U.K. and the Czech Republic, respectively. The calculated percentages of gasoline-derived Pb in peat (≤55% for the British Isles and ≤63% for the Czech Republic

  7. Laminoplasty Does not Lead to Worsening Axial Neck Pain in the Properly Selected Patient With Cervical Myelopathy: A Comparison With Laminectomy and Fusion.

    Science.gov (United States)

    Stephens, Byron F; Rhee, John M; Neustein, Thomas M; Arceo, Rafael

    2017-12-15

    Retrospective cohort study of prospectively collected data. To determine if laminoplasty (LP) is associated with worsening axial neck pain in patients with multilevel cervical myelopathy, and to compare neck pain, clinical outcomes, and radiographic measures in a group undergoing laminectomy and fusion (LF). Postoperative new or worsening axial neck pain is commonly cited as a major disadvantage of laminoplasty. However, there remains a paucity of corroborative data from large series. Following institutional review board approval, we reviewed the medical records, radiographs, and prospective clinical outcomes database of 85 patients undergoing LP and 52 patients undergoing LF for cervical myelopathy with minimum 1-year radiographic follow-up and average clinical follow-up of 18.5 months. LP was performed in those with neutral to lordotic C2-7 alignment and who did not complain of diffuse axial pain. Otherwise, LF was performed. Clinical outcomes included visual analogue score (VAS)-neck pain, VAS-total pain, neck disability index (NDI), short form 36, modified Japanese Orthopaedic Association (mJOA), and several radiographic parameters. VAS-neck did not worsen in LP (-0.2, P = 0.54) and did improve in LF (-2.0, P = 0.0013). VAS-total improved significantly in both groups (LF -1.04 ± 0.52, P = 0.05; LP -1.4 ± 0.51, P = 0.008). NDI improved in both groups, but was significant in only LP (LP decreased 6.79 ± 2.25, P = 0.0032; LF decreased 4.01 ± 3.05, P = 0.19). mJOA scores improved significantly in both groups (LP improved 2.89 ± 0.27, P cervical lordosis in both groups that was significant in LP (LP 2.92° loss, P = 0.0181; LF 1.25° loss, P = 0.53). In a carefully selected group of myelopathic patients without significant diffuse axial pain preoperatively and appropriate sagittal alignment, laminoplasty did not lead to worsening axial neck pain, and it was associated with significant improvements in other

  8. Design of the fuel element 'snow-flake' in uranium oxide, canned with aluminium, for the experimental reactor EL 3 (1960); Etude d'un element combustible en oxyde d'uranium gaine d'aluminium, type ''cristal de neige'' pour la pile EL 3 (1960)

    Energy Technology Data Exchange (ETDEWEB)

    Gauthron, M; Guibert, B [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    This report sums up the main studies have been carried out on the fuel element 'Snowflake' (uranium oxide, canned with aluminium), designed to replace the present element of the experimental reactor EL3 in order to increase the reactivity without modifying the neutron flux/thermal power ratio. (author) [French] Ce rapport resume les principales etudes qui ont ete faites sur l'element combustible 'Cristal de Neige' (a oxyde d'uranium, gaine d'aluminium) destine a remnlacer l'element actuel du reacteur experimental EL3, afin d'en augmenter la reactivite sans modifier le rapport flux neutronique-puissance thermique. (auteur)

  9. Neutron production in spallation reactions of 0.9 and 1.5 GeV protons on a thick lead target. Comparison between experimental data and Monte-Carlo simulations

    International Nuclear Information System (INIS)

    Krasa, A.; Krizek, F.; Wagner, V.; Kugler, A.; Henzl, V.; Henzlova, D.; Majerle, M.; Adam, J.; Caloun, P.; Bradnova, V.; Chultem, D.; Kalinnikov, V.G.; Krivopustov, M.I.; Solnyshkin, A.A.; Stegajlov, V.I.; Tsupko-Sitnikov, V.M.; Tumehndehlgehr, Ts.; Vasil'ev, S.I.

    2005-01-01

    This paper reports on two experiments performed at the Synchrophasotron/Nuclotron accelerator complex at JINR. Relativistic protons with energies 885 MeV and 1.5 GeV hit a massive cylindrical lead target. The spatial and energetic distributions of the neutron field produced by the spallation reactions were measured by the activation of Al, Au, Bi, Co, and Cu foils placed on the surface of the target and close to it. The yields of the radioactive nuclei produced by threshold reactions in these foils were determined by the analyses of their γ spectra. The comparison with Monte-Carlo based simulations was performed both with the LAHET+MCNP code and the MCNPX code

  10. Neutron Production in Spallation Reactions of 0.9 and 1.5 GeV Protons on a Thick Lead Target. Comparison between Experimental Data and Monte-Carlo Simulations

    CERN Document Server

    Krasa, A; Bradnova, V; Caloun, P; Chultem, D; Henzl, V; Henzlová, D; Kalinnikov, V G; Krivopustov, M I; Krízek, F; Kugler, A; Majerle, M; Solnyshkin, A A; Stegailov, V I; Tsoupko-Sitnikov, V M; Tumendelger, T; Vasilev, S I; Wagner, V; Nuclear Physics Institute of Academy of Sciences of Czech Republic, Rez, Czech Republic

    2005-01-01

    This paper reports on two experiments performed at the Synchrophasotron/Nuclotron accelerator complex at JINR. Relativistic protons with energies 885 MeV and 1.5 GeV hit a massive cylindrical lead target. The spatial and energetic distributions of the neutron field produced by the spallation reactions were measured by the activation of Al, Au, Bi, Co, and Cu foils placed on the surface of the target and close to it. The yields of the radioactive nuclei produced by threshold reactions in these foils were determined by the analyses of their $\\gamma$ spectra. The comparison with Monte-Carlo based simulations was performed both with the LAHET+MCNP code and the MCNPX code.

  11. The Chateau de Cristal data acquisition system

    International Nuclear Information System (INIS)

    Villard, M.M.

    1987-05-01

    This data acquisition system is built on several dedicated data transfer busses: ADC data readout through the FERA bus, parallel data processing in two VME crates. High data rates and selectivities are performed via this acquisition structure and new developed processing units. The system modularity allows various experiments with additional detectors

  12. Música e imágenes hasta la llegada del cine. (Linterna mágica, armónica de cristal, fantasmagorías y teatro de sombras

    Directory of Open Access Journals (Sweden)

    Armell Femenía, Montserrat

    2003-12-01

    Full Text Available The prehistory of talking movies where the coordination of moving images and sound is concerned, comprises a very extensive period of time of thousands of years stretching from the musical illustration of projected shadows as documented in Ancient China, up to practically the very dawn of cinematography, a technological advance unthinkable today more than ever without the contribution that music and sound have made to the so-called seventh art. This study sets out to offer an overall view of the history of continued human interest in capturing movement in sound and vision at the same moment in time, paying particular attention to certain technical achievements of some relevance (the magic lantern, the harmonic crystal, phantasmagories and the theatre of shadows within the evolution that was to facilitate the birth of the "talkies". A simple introduction to a fascinating and modern world, that, from a purely musicological view is practically nonexistent today (the meagre and marginal bibliography available is the best evidence of that and which requires new and more detailed studies to be done.

    La "pre-historia" del cine hablado, en lo relativo a la coordinación de imágenes en movimiento y sonido, supone un período extensísimo de tiempo, que abarca miles de años, desde la ilustración sonora de sombras proyectadas documentada en la antigua China, hasta prácticamente los albores del cinematógrafo, un avance tecnológico impensable —hoy en día más que nunca— sin la aportación que música y sonido han hecho al denominado séptimo arte. El presente trabajo pretende ofrecer una panorámica de la historia de la —documentadamente inconexa, aunque continua— preocupación humana por fijar el movimiento de un modo visual y sonoro a un tiempo, prestando particular atención a algunos logros técnicos de especial relevancia (la linterna mágica, la armónica de cristal, las fantasmagorías, el teatro de sombras, dentro del recorrido

  13. Design of the fuel element 'snow-flake' in uranium oxide, canned with aluminium, for the experimental reactor EL 3 (1960); Etude d'un element combustible en oxyde d'uranium gaine d'aluminium, type ''cristal de neige'' pour la pile EL 3 (1960)

    Energy Technology Data Exchange (ETDEWEB)

    Gauthron, M.; Guibert, B. [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    This report sums up the main studies have been carried out on the fuel element 'Snowflake' (uranium oxide, canned with aluminium), designed to replace the present element of the experimental reactor EL3 in order to increase the reactivity without modifying the neutron flux/thermal power ratio. (author) [French] Ce rapport resume les principales etudes qui ont ete faites sur l'element combustible 'Cristal de Neige' (a oxyde d'uranium, gaine d'aluminium) destine a remnlacer l'element actuel du reacteur experimental EL3, afin d'en augmenter la reactivite sans modifier le rapport flux neutronique-puissance thermique. (auteur)

  14. Lead levels - blood

    Science.gov (United States)

    Blood lead levels ... is used to screen people at risk for lead poisoning. This may include industrial workers and children ... also used to measure how well treatment for lead poisoning is working. Lead is common in the ...

  15. Lead Poisoning Prevention Tips

    Science.gov (United States)

    ... or removed safely. How are children exposed to lead? Lead-based paint and lead contaminated dust are ... What can be done to prevent exposure to lead? It is important to determine the construction year ...

  16. Comparison of three dosimetric techniques to take in account lung tumor motion: gating-like technique results lead to advice the use of gating device even in the cases of pre-operative irradiation

    International Nuclear Information System (INIS)

    Beneyton, V.; Billaud, G.; Niederst, C.; Meyer, P.; Schumacher, C.; Karamanoukian, D.; Noel, G.; Bourhala, K.

    2010-01-01

    Purpose: Comparison of three dosimetric techniques of lung tumor delineation to integrate tumor motion during breathing. Patients and method: Nineteen patients with T1-3N0M0 malignant lung tumor were treated with definitive chemoradiotherapy (14 cases) or pre-surgery chemo radiation. Doses were, respectively, 66 and 46 Gy. CT-scan for delineation was performed during three phases of breathing: free breathing and deep breath-hold inspiration and expiration. G.T.V. (gross tumor volume) was delineated on the three sequences. The classic technique included G.T.V. from the free-breathing sequence plus a C.T.V. (clinical target volume) margin of 5 to 8 mm plus a P.T.V. (planning target volume) margin of 7 to 10 mm (including I.T.V. [internal target volume] margin and set-up margin). The gating-like technique included G.T.V. from the deep breath-hold inspiration sequence plus a C.T.V. margin of 5 to 8 mm plus a P.T.V. margin of 2 mm. The three-volume technique, included G.T.V. as a result of the fusion of G.T.V.s from the three sequences plus a C.T.V. margin of 5 to 8 mm plus a P.T.V. margin of 2 mm. Dosimetry was calculated for the three P.T.V.s, if possible, with the same fields number and position. Dose constraints and rules were imposed to accept dosimetries: firstly spinal cord maximal dose less than 45 Gy, followed by V95 % for P.T.V. greater than or equal to 95 %, and V20 GY Gy for lung less than or equal to 30 %, V30 GY Gy for lung less than or equal to 20 %. Results: G.T.V.s were not statistically different between the three methods of delineation. P.T.V.s were significantly lower with the gating-like technique. V95% of the P.T.V. were not different between the three techniques. With the classic-, the gating-like- and the 3-volume techniques, dosimetry was considered as acceptable, respectively in 15, 18 and 15 cases. Comparisons of constraint values showed that the gating-like method gave the best results. In the case of pre-operative management, the gating

  17. Lead (Pb) Air Pollution

    Science.gov (United States)

    ... Regional Offices Labs and Research Centers Lead (Pb) Air Pollution Contact Us Share As a result of EPA's ... and protect aquatic and terrestrial ecosystems. Lead (Pb) Air Pollution Basic Information How does lead get in the ...

  18. Cryogenic current leads

    Energy Technology Data Exchange (ETDEWEB)

    Zizek, F.

    1982-01-01

    Theoretical, technical and design questions are examined of cryogenic current leads for SP of magnetic systems. Simplified mathematical models are presented for the current leads. To illustrate modeling, the calculation is made of the real current leads for 500 A and three variants of current leads for 1500 A for the enterprise ''Shkoda.''

  19. Lead - nutritional considerations

    Science.gov (United States)

    ... billion people had toxic (poisonous) blood lead levels. Food Sources Lead can be found in canned goods if there is lead solder in the ... to bottled water for drinking and cooking. Avoid canned goods from foreign ... cans goes into effect. If imported wine containers have a lead foil ...

  20. Comparative experimental study of myocardial protection with crystalloid solutions for heart transplantation Estudo comparativo experimental da proteção miocárdica com soluções cristalóides para transplante cardíaco

    Directory of Open Access Journals (Sweden)

    Melchior Luiz Lima

    2012-03-01

    Full Text Available BACKGROUND: There is a growing need to improve myocardial protection, which will lead to better performance of cardiac operations and reduce morbidity and mortality. Therefore, the objective of this study was to compare the efficacy of myocardial protection solution using both intracellular and extracellular crystalloid type regarding the performance of the electrical conduction system, left ventricular contractility and edema, after being subjected to ischemic arrest and reperfusion. METHODS: Hearts isolated from male Wistar (n=32 rats were prepared using Langendorff method and randomly divided equally into four groups according the cardioprotective solutions used Krebs-Henseleit-Buffer (KHB, Bretschneider-HTK (HTK, St. Thomas-1 (STH-1 and Celsior (CEL. After stabilization with KHB at 37ºC, baseline values (control were collected for heart rate (HR, left ventricle systolic pressure (LVSP, maximum first derivate of rise left ventricular pressure (+dP/dt, maximum first derivate of fall left ventricular pressure (-dP/dt and coronary flow (CF. The hearts were then perfused at 10ºC for 5 min and kept for 2 h in static ischemia at 20ºC in each cardioprotective solution. Data evaluation was done using analysis of variance in completely randomized One-Way ANOVA and Tukey's test for multiple comparisons. The level of statistical significance chosen was PKHB>STH-1.INTRODUÇÃO: Existe crescente necessidade de aprimorar a proteção miocárdica, para melhor desempenho das operações cardíacas e diminuição da morbimortalidade. Portanto, o objetivo deste estudo foi comparar a eficácia da proteção miocárdica usando tanto solução cristaloide tipo intracelular como extracelular quanto ao desempenho do sistema de condução elétrica, contratilidade do ventrículo esquerdo e edema, após parada isquêmica e posterior reperfusão. MÉTODOS: Corações isolados de ratos Wistar foram montados em Langendorff e aleatoriamente divididos em quatro grupos

  1. Lead inclusions in aluminium

    International Nuclear Information System (INIS)

    Johnson, E.; Johansen, A.; Sarholt-Kristensen, L.; Andersen, H.H.; Grabaek, L.; Bohr, J.

    1990-01-01

    Ion implantation at room temperature of lead into aluminum leads to spontaneous phase separation and formation of lead precipitates growing topotactically with the matrix. Unlike the highly pressurized (∼ 1-5 GPa) solid inclusions formed after noble gas implantations, the pressure in the lead precipitates is found to be less than 0.12 GPa. Recently the authors have observed the result that the lead inclusions in aluminum exhibit both superheating and supercooling. In this paper they review and elaborate on these results. Small implantation-induced lead precipitates embedded in an aluminum matrix were studied by x-ray diffraction

  2. VOLUMETRIC LEAD ASSAY

    International Nuclear Information System (INIS)

    Ebadian, M.A.; Dua, S.K.; Roelant, David; Kumar, Sachin

    2001-01-01

    This report describes a system for handling and radioassay of lead, consisting of a robot, a conveyor, and a gamma spectrometer. The report also presents a cost-benefit analysis of options: radioassay and recycling lead vs. disposal as waste

  3. NA49: lead-lead collision

    CERN Multimedia

    1996-01-01

    This is an image of an actual lead ion collision taken from tracking detectors on the NA49 experiment, part of the heavy ion project at CERN. These collisions produce a very complicated array of hadrons as the heavy ions break up. It is hoped that one of these collisions will eventually create a new state of matter known as quark-gluon plasma.

  4. Uranium-lead systematics

    International Nuclear Information System (INIS)

    Wickman, F.E.

    1983-01-01

    The method of Levchenkov and Shukolyukov for calculating age and time disturbance of minerals without correction for original lead is generalized to include the cases when (1) original lead and radiogenic lead leach differently, and (2) the crystals studied consist of a core and a mantle. It is also shown that a straight line obtained from the solution of the equations is the locus of the isotopic composition of original lead. (Auth.)

  5. Atrioventricular Pacemaker Lead Reversal

    Directory of Open Access Journals (Sweden)

    Mehmet K Aktas, MD

    2007-01-01

    Full Text Available During cardiac surgery temporary epicardial atrial and ventricular leads are placed in case cardiac pacing is required postoperatively. We present the first reported series of patients with reversal of atrioventricular electrodes in the temporary pacemaker without any consequent deleterious hemodynamic effect. We review the electrocardiographic findings and discuss the findings that lead to the discovery of atrioventricular lead reversal.

  6. Lead Poisoning (For Parents)

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Lead Poisoning KidsHealth / For Parents / Lead Poisoning What's in ... Print en español La intoxicación por plomo About Lead Poisoning If you have young kids, it's important ...

  7. Lead-iron phosophate glass

    International Nuclear Information System (INIS)

    Sales, B.C.; Boatner, L.A.

    1988-01-01

    The lead-iron phosphate nuclear waste glasses (LIPNWG) are the subject of the present chapter. They were discovered in 1984 while the authors were attempting to find a sintering aid for certain types of crystalline monazite ceramic high-level nuclear waste forms. In the present chapter, the term waste glass is synonymous with nuclear waste glass (NWG), and the acronym LIP is often used for lead-iron phosphate. Lead-iron phosphate glasses, like many of the previously studied phosphate glasses, are corrosion resistant in aqueous solutions at temperatures below 100 degrees C, and they can be melted and poured at temperatures that are relatively low in comparison with the processing temperatures required for current silicate glass compositions. Unlike the phosphate glasses investigated previously, however, LIPNWGs do not suffer from alteration due to devitrification during realistic and readily, achievable cooling periods. Additionally, lead-iron phosphate glass melts are not nearly as corrosive as the sodium phosphate melts investigated during the 1960s; and, therefore, they can be melted and processed using crucibles made from a variety of materials

  8. Superconductivity in nanostructured lead

    Science.gov (United States)

    Lungu, Anca; Bleiweiss, Michael; Amirzadeh, Jafar; Saygi, Salih; Dimofte, Andreea; Yin, Ming; Iqbal, Zafar; Datta, Timir

    2001-01-01

    Three-dimensional nanoscale structures of lead were fabricated by electrodeposition of pure lead into artificial porous opal. The size of the metallic regions was comparable to the superconducting coherence length of bulk lead. Tc as high as 7.36 K was observed, also d Tc/d H was 2.7 times smaller than in bulk lead. Many of the characteristics of these differ from bulk lead, a type I superconductor. Irreversibility line and magnetic relaxation rates ( S) were also studied. S( T) displayed two maxima, with a peak value about 10 times smaller than that of typical high- Tc superconductors.

  9. Lead in the environment

    Science.gov (United States)

    Pattee, Oliver H.; Pain, Deborah J.; Hoffman, David J.; Rattner, Barnett A.; Burton, G. Allen; Cairns, John

    2003-01-01

    Anthropogenic uses of lead have probably altered its availability and environmental distribution more than any other toxic element. Consequently, lead concentrations in many living organisms may be approaching thresholds of toxicity for the adverse effects of lead. Such thresholds are difficult to define, as they vary with the chemical and physical form of lead, exposure regime, other elements present and also vary both within and between species. The technological capability to accurately quantify low lead concentrations has increased over the last decade, and physiological and behavioral effects have been measured in wildlife with tissue lead concentrations below those previously considered safe for humans.s.236 Consequently. lead criteria for the protection of wildlife and human health are frequently under review, and 'thresholds' of lead toxicity are being reconsidered. Proposed lead criteria for the protection of natural resources have been reviewed by Eisler. Uptake of lead by plants is limited by its generally low availability in soils and sediments, and toxicity may be limited by storage mechanisms and its apparently limited translocation within most plants. Lead does not generally accumulate within the foliar parts of plants, which limits its transfer to higher trophic levels. Although lead may concentrate in plant and animal tissues, no evidence of biomagnification exists. Acid deposition onto surface waters and soils with low buffering capacity may influence the availability of lead for uptake by plants and animals, and this may merit investigation at susceptible sites. The biological significance of chronic low-level lead exposure to wildlife is sometimes difficult to quantify. Animals living in urban environments or near point sources of lead emission are inevitably subject to greater exposure to lead and enhanced risk of lead poisoning. Increasingly strict controls on lead emissions in many countries have reduced exposure to lead from some sources

  10. ALICE: Simulated lead-lead collision

    CERN Multimedia

    2003-01-01

    This track is an example of simulated data modelled for the ALICE detector on the Large Hadron Collider (LHC) at CERN, which will begin taking data in 2008. ALICE will focus on the study of collisions between nuclei of lead, a heavy element that produces many different particles when collided. It is hoped that these collisions will produce a new state of matter known as the quark-gluon plasma, which existed billionths of a second after the Big Bang.

  11. Secondary lead production

    Energy Technology Data Exchange (ETDEWEB)

    Hollis, R.G.

    1990-10-16

    This invention is concerned with the efficient recovery of soft lead from the paste component of used automobile lead-acid storage batteries. According to the invention, a scrap which contains lead oxide, lead sulfate, and antimony in an oxidized state is processed in the following steps to recover lead. A refractory lined reaction vessel is continuously charged with the scrap, along with a reductant effective for reducing lead oxide. The charged material is melted and agitated by means of a submerged lance at 900-1150{degree}C whereby some of the lead oxide of the scrap is reduced to form molten lead. A slag layer is then formed above the molten lead, and an amount of lead oxide is maintained in the slag layer. The molten lead, now containing under 0.5 wt % of antimony, is removed, and the antimony oxide in the scrap is concentrated as oxide in the slag layer. Preferred embodiments of the invention result in the production, in a single step, of a soft lead substantially free of antimony. The slag may be subsequently treated to reduce the antimony oxide and produce a valuable antimony-lead product. Further advantages of the process are that a wet battery paste may be used as the feed without prior drying, and the process can be conducted at a temperature 100-150{degree}C lower than in previously known methods. In addition, a smaller reactor can be employed which reduces both capital cost and fuel costs. The process of the invention is illustrated by descriptions of pilot plant tests. 1 fig.

  12. Lead-Free Piezoelectrics

    CERN Document Server

    Nahm, Sahn

    2012-01-01

    Ecological restrictions in many parts of the world are demanding the elimination of Pb from all consumer items. At this moment in the piezoelectric ceramics industry, there is no issue of more importance than the transition to lead-free materials. The goal of Lead-Free Piezoelectrics is to provide a comprehensive overview of the fundamentals and developments in the field of lead-free materials and products to leading researchers in the world. The text presents chapters on demonstrated applications of the lead-free materials, which will allow readers to conceptualize the present possibilities and will be useful for both students and professionals conducting research on ferroelectrics, piezoelectrics, smart materials, lead-free materials, and a variety of applications including sensors, actuators, ultrasonic transducers and energy harvesters.

  13. Lead Poison Detection

    Science.gov (United States)

    1976-01-01

    With NASA contracts, Whittaker Corporations Space Science division has developed an electro-optical instrument to mass screen for lead poisoning. Device is portable and detects protoporphyrin in whole blood. Free corpuscular porphyrins occur as an early effect of lead ingestion. Also detects lead in urine used to confirm blood tests. Test is inexpensive and can be applied by relatively unskilled personnel. Similar Whittaker fluorometry device called "drug screen" can measure morphine and quinine in urine much faster and cheaper than other methods.

  14. Chronic lead intoxication; Chronische Bleiintoxikation

    Energy Technology Data Exchange (ETDEWEB)

    Wieseler, B.; Leng, G. [Duesseldorf Univ. (Germany). Inst. fuer Hygiene; Lenz, S.; Schultz, C. [Klinikum Remscheid GmbH, Remscheid (Germany); Wilhelm, M. [Bochum Univ. (Germany). Inst. fuer Hygiene, Sozial- und Umweltmedizin

    1999-02-01

    The case of a female 68 years old patient is described. Here, a chronic lead intoxication was diagnosed after a two year old medical history with increasing attacks of colic-like abdominal pain often described as life-threatening. After repeated hospitalizations and intensive search for the cause of the symptoms, porphyria and anemia was found to be a sign of a chronic lead poisoning. The blood lead concentrations were always about a level of 600 {mu}g/L. The source of exposure could not be found by now. Neither home inspection nor environmental investigations have shown a recent source of lead intake by the patient. However, a possible occupational source of lead exposure at a blast furnace was established by anamnesis for 1952 to 1962. Thus, osteoporosis induced lead mobilisation was suspected. Noticeable are the results of the six abdominal survey radiographies taken during hospitalization within one year; three radiographies were taken following clinical admission and three before discharge of the patient. In comparison, the course shows a chronic relapsing alimentary supply from metallic particles of unknown genesis. The patient was treated with the sodium salt of 2,3-dimercapto-1-propansulfonic acid (DMPS, Dimaval{sup TM}). She was free of complain afterwards. Following therapy, the blood lead concentrations fell under a level of 400 {mu}m/L, but after several weeks the lead level raised up to the original level of 600 {mu}g/L. (orig.) [Deutsch] Es wird eine 68jaehrige Patientin vorgestellt, bei der nach fast zweijaehriger Krankengeschichte, die gekennzeichnet war durch rezidivierende, teils als lebensbedrohlich geschilderte Bauchkoliken, eine chronische Bleiintoxikation diagnostiziert wurde. Erst nach wiederholten stationaeren Krankenhausaufenthalten mit intensiver Suche nach der Krankheitsursache wurden das Krankheitsbild und die Laborwerte durch Zusatzuntersuchungen ergaenzt, so dass sich in der festgestellten Porphyrie und Anaemie die Diagnose der

  15. Effects of occupational lead exposure.

    Science.gov (United States)

    Wang, Y L; Lu, P K; Chen, Z Q; Liang, Y X; Lu, Q M; Pan, Z Q; Shao, M

    1985-01-01

    Fifty-three workers in a battery factory, 52 solderers in a television factory, and 50 embroidery workers (a reference group) were studied. The average air lead levels of the three workplaces were 0.578 mg/m3, 0.002 mg/m3, and 0.001 mg/m3, respectively. Adverse effects in terms of clinical manifestations and biochemical criteria were evident among the battery factory workers. A significant dose-response relationship existed between the toxic effects and the air lead levels. The solderers showed no apparent abnormalities in comparison with the embroidery workers. The early clinical manifestations were dysfunction of the central nervous system, indigestion, arthralgia, and myalgia in the extremities. A positive association was observed between the prevalence of fatigue, mild abdominal pain, and arthralgia and the blood lead (PbB), urinary lead (PbU), and zinc protoporphyrin (ZPP) levels. The symptomatic threshold values of PbB, PbU, and ZPP were 30 micrograms/dl (1.5 mumol/l), 0.045 mg/l (0.2 mumol/l), and 40 micrograms/dl (0.7 mumol/l), respectively. The PbB, PbU, free erythrocyte protoporphyrin, and ZPP levels and the blood aminolevulinic dehydratase ratio could be used as indicators of lead exposure, although ZPP is preferred for a preventive monitoring program. The motor and sensory conduction velocities of the median nerve were slower in the exposed groups than in the reference group. No effects on behavioral function were observed among the solderers.

  16. Association of Lead Levels and Cerebral Palsy

    Science.gov (United States)

    Bansal, Neha; Aggarwal, Anju; Faridi, M. M. A.; Sharma, Tusha; Baneerjee, B. D.

    2017-01-01

    Background: Cerebral palsy is a common motor disability in childhood. Raised lead levels affect cognition. Children with cerebral palsy may have raised lead levels, further impairing their residual cognitive motor and behavioral abilities. Environmental exposure and abnormal eating habits may lead to increased lead levels. Aims and Objectives: To measure blood lead levels in children with cerebral palsy and compare them with healthy neurologically normal children. To correlate blood lead levels with environmental factors. Material and Methods: Design: Prospective case-control study. Setting: Tertiary care hospital. Participants: Cases comprised 34 children with cerebral palsy, and controls comprised 34 neurologically normal, age- and sex-matched children. Methods: Clinical and demographic details were recorded as per proforma. Detailed environmental history was recorded to know the source of exposure to lead. These children were investigated and treated as per protocol. Venous blood was collected in ethylenediaminetetraacetic acid vials for analysis of blood lead levels. Lead levels were estimated by Schimadzu Flame AA-6800 (atomic absorption spectrophotometer). Data were analyzed using SPSS version 17. P pica were 12.33 ± 10.02 µg/dL in comparison to children with no history of pica, 6.70 ± 4.60 µg/dL (P = .029). No correlation was found between hemoglobin and blood lead levels in cases and controls. Conclusion: In our study, blood lead levels are raised in children with cerebral palsy. However, further studies are required to show effects of raised levels in these children. PMID:28491920

  17. Mercury, Lead, Cadmium, Cobalt, Arsenic and Selenium in the Blood of Semipalmated Sandpipers (Calidris pusilla from Suriname, South America: Age-related Differences in Wintering Site and Comparisons with a Stopover Site in New Jersey, USA

    Directory of Open Access Journals (Sweden)

    Joanna Burger

    2018-05-01

    Full Text Available It is essential to understand contaminant exposure and to compare levels of contaminants in organisms at different ages to determine if there is bioaccumulation, and to compare levels encountered in different geographical areas. In this paper, we report levels of mercury, lead, cadmium, cobalt, arsenic and selenium in the blood of semipalmated sandpipers (Calidris pusilla wintering in Suriname as a function of age, and compare them to blood levels in northbound migrants at a stopover in Delaware Bay, New Jersey. We found (1 young birds had higher levels of cadmium, cobalt, and lead than adults (after second year birds; (2 there were no age-related differences for arsenic, mercury and selenium; (3 only four of the possible 16 inter-metal correlations were significant, at the 0.05 level; (4 the highest correlation was between cadmium and lead (Kendall tau = 0.37; and (5 the adult sandpipers had significantly higher levels of cadmium, mercury and selenium in Suriname than in New Jersey, while the New Jersey birds had significantly higher levels of arsenic. Suriname samples were obtained in April, after both age classes had spent the winter in Suriname, which suggests that sandpipers are accumulating higher levels of trace elements in Suriname than in Delaware Bay. The levels of selenium may be within a range of concern for adverse effects, but little is known about adverse effect levels of trace elements in the blood of wild birds.

  18. Lead poisoning in dogs

    Energy Technology Data Exchange (ETDEWEB)

    Bond, E; Kubin, R

    1949-01-01

    Diagnosis was made from clinical observation and laboratory examination of nine cases. A successful treatment is described based on the similarity of the metabolism of lead and calcium, the lead being deposited in the bones where it is harmless, if it remains there. Details are given of the treatment.

  19. Developmental immunotoxicology of lead

    International Nuclear Information System (INIS)

    Dietert, Rodney R.; Lee, Ji-Eun; Hussain, Irshad; Piepenbrink, Michael

    2004-01-01

    The heavy metal, lead, is a known developmental immunotoxicant that has been shown to produce immune alterations in humans as well as other species. Unlike many compounds that exert adverse immune effects, lead exposure at low to moderate levels does not produce widespread loss of immune cells. In contrast, changes resulting from lead exposure are subtle at the immune cell population level but, nevertheless, can be functionally dramatic. A hallmark of lead-induced immunotoxicity is a pronounced shift in the balance in T helper cell function toward T helper 2 responses at the expense of T helper 1 functions. This bias alters the nature and range of immune responses that can be produced thereby influencing host susceptibility to various diseases. Immunotoxic responses to lead appear to differ across life stages not only quantitatively with regard to dose response, but also qualitatively in terms of the spectrum of immune alterations. Experimental studies in several lab animal species suggest the latter stages of gestation are a period of considerable sensitivity for lead-induced immunotoxicity. This review describes the basic characteristics of lead-induced immunotoxicity emphasizing experimental animal results. It also provides a framework for the consideration of toxicant exposure effects across life stages. The existence of and probable basis for developmental windows of immune hyper-susceptibility are presented. Finally, the potential for lead to serve as a perinatal risk factor for childhood asthma as well as other diseases is considered

  20. Leading Educational Change Wisely

    Science.gov (United States)

    Forrester, Gillian

    2011-01-01

    In this article, the author reviews Christopher Branson's book entitled "Leading Educational Change Wisely". The book provides an alternative and engaging perspective on leading educational change. Branson utilises "wisdom" as its central conceptual device to present a thought-provoking and philosophical account on how leaders are able to build a…

  1. Lead-free piezoceramics.

    Science.gov (United States)

    Saito, Yasuyoshi; Takao, Hisaaki; Tani, Toshihiko; Nonoyama, Tatsuhiko; Takatori, Kazumasa; Homma, Takahiko; Nagaya, Toshiatsu; Nakamura, Masaya

    2004-11-04

    Lead has recently been expelled from many commercial applications and materials (for example, from solder, glass and pottery glaze) owing to concerns regarding its toxicity. Lead zirconium titanate (PZT) ceramics are high-performance piezoelectric materials, which are widely used in sensors, actuators and other electronic devices; they contain more than 60 weight per cent lead. Although there has been a concerted effort to develop lead-free piezoelectric ceramics, no effective alternative to PZT has yet been found. Here we report a lead-free piezoelectric ceramic with an electric-field-induced strain comparable to typical actuator-grade PZT. We achieved this through the combination of the discovery of a morphotropic phase boundary in an alkaline niobate-based perovskite solid solution, and the development of a processing route leading to highly textured polycrystals. The ceramic exhibits a piezoelectric constant d33 (the induced charge per unit force applied in the same direction) of above 300 picocoulombs per newton (pC N(-1)), and texturing the material leads to a peak d33 of 416 pC N(-1). The textured material also exhibits temperature-independent field-induced strain characteristics.

  2. Lead poisoning in dogs

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, M R; Lewis, G

    1963-08-03

    Within a short period, 14 cases of lead poisoning in the dogs have been encountered. A detailed record appears justified as no published reference can be found to this condition occurring in Britain and because reports from other countries stress the similarity of the clinical manifestations of lead poisoning to those of the common infections of the dog. Five of the 14 clinical cases of lead poisoning are described. The available literature is reviewed and the diagnosis and significance of the condition discussed. 19 references, 2 tables.

  3. Impacts of aerosol lead to natural ecosystems

    International Nuclear Information System (INIS)

    Murozumi, Masayo; Nakamura, Seiji; Yoshida, Katsumi

    1982-01-01

    Impacts of aerosol lead have changed the concentration and isotopic ratios of the element circulating in remote ecosystems in the Hidaka and Tarumae mountains. Concentrations of lead in successive each 10 years ring veneer of Cercidiphyllum Japonica show that amount of the element residing on the bark and supwood layers has increased by a factor of 2 or more in comparison with that of the core part. The isotopic ratios of lead in the basement rocks and soils under the ecosystems converge to a certain narrow spot along the isochron Iine of the element, and distinguish their geochronogical characteristics from other leads of different sources. In these ecosystems, however, the lead isotopic ratios of materials exposed to the atmosphere are similar to those of foreign and anthropogenic aerosol lead but are evidently dissimilar to those of the rocks and soils. Furthermore, the lead isotopic ratios in yearly ring veneers of Ceridiphyllum Japonica and Ostrya Japonica show a certain differentiation towards the bark from the core, i.e., an approach to those of anthropogenic aerosol lead from those of the basement rocks and soils, as listed in Table 7. The lead burden per hectare in these remote ecosystems has increased to 4 g by the impact of 2 g of aerosol lead. (author)

  4. Biological fractionation of lead isotopes in Sprague-Dawley rats lead poisoned via the respiratory tract.

    Directory of Open Access Journals (Sweden)

    Jing Wu

    Full Text Available It was considered that lead isotope ratios did not change during physical, chemical, or biological processes. Thus, lead isotope ratios have been used as fingerprints to identify possible lead sources. However, recent evidence has shown that the lead isotope ratios among different biological samples in human are not always identical from its lead origins in vitro. An animal experiment was conducted to explore the biological fractionation of lead isotopes in biological systems.24 male Sprague-Dawley (SD rats were divided into groups that received acute lead exposure (0, 0.02, 0.2, or 2 mg/kg body weight of lead acetate via the respiratory route every day for 5 days. Biological samples (i.e., blood, urine, and feces were collected for comparison with the lead acetate (test substance and the low-lead animal feed (diet administered to the rats. The lead isotope ratios were determined by inductively coupled plasma mass spectrometry (ICP-MS.There are significant differences (p<0.05 in lead isotope ratios between blood, urine, and feces. Moreover, a nonlinear relationship between the blood lead concentration and the blood lead isotope ratios was observed. There is also a threshold effect to the fractionation function. Only the blood isotope ratio of (204Pb/(206Pb matches the test substance well. As for feces, when (204Pb/(206Pb ratio is considered, there is no significant difference between feces-test substance pairs in medium and high dose group.The biological fractionation of lead isotopes in SD rats was observed. Moreover, there might be a threshold for the biological fractionation of lead isotopes which is depending on whole blood lead level. It is considered to be more reliable that we compared the isotope ratios of potential lead hazards with both blood and feces lead fingerprints especially for (204Pb/(206Pb ratio under high-dose exposure.

  5. Association of Lead Levels and Cerebral Palsy

    Directory of Open Access Journals (Sweden)

    Neha Bansal MD

    2017-03-01

    Full Text Available Background: Cerebral palsy is a common motor disability in childhood. Raised lead levels affect cognition. Children with cerebral palsy may have raised lead levels, further impairing their residual cognitive motor and behavioral abilities. Environmental exposure and abnormal eating habits may lead to increased lead levels. Aims and Objectives: To measure blood lead levels in children with cerebral palsy and compare them with healthy neurologically normal children. To correlate blood lead levels with environmental factors. Material and Methods: Design: Prospective case-control study. Setting: Tertiary care hospital. Participants: Cases comprised 34 children with cerebral palsy, and controls comprised 34 neurologically normal, age- and sex-matched children. Methods: Clinical and demographic details were recorded as per proforma. Detailed environmental history was recorded to know the source of exposure to lead. These children were investigated and treated as per protocol. Venous blood was collected in ethylenediaminetetraacetic acid vials for analysis of blood lead levels. Lead levels were estimated by Schimadzu Flame AA-6800 (atomic absorption spectrophotometer. Data were analyzed using SPSS version 17. P < .05 was taken as significant. Results: Mean blood lead levels were 9.20 ± 8.31 µg/dL in cerebral palsy cases and 2.89 ± 3.04 µg/dL in their controls (P < .001. Among children with cerebral palsy, 19 (55.88% children had blood lead levels ≥5 µg/dL. Lead levels in children with pica were 12.33 ± 10.02 µg/dL in comparison to children with no history of pica, 6.70 ± 4.60 µg/dL (P = .029. No correlation was found between hemoglobin and blood lead levels in cases and controls. Conclusion: In our study, blood lead levels are raised in children with cerebral palsy. However, further studies are required to show effects of raised levels in these children.

  6. Lead in Construction

    National Research Council Canada - National Science Library

    1993-01-01

    Although Occupational Safety and Health Administration (OSHA) regulations for occupational lead exposure have been in effect since 1971 for the construction and general industries, the agency regulations for general industry in 1978...

  7. Radiation shielding lead shield

    International Nuclear Information System (INIS)

    Dei, Shoichi.

    1991-01-01

    The present invention concerns lead shields for radiation shielding. Shield boxes are disposed so as to surround a pipeline through which radioactive liquids, mists or like other objects are passed. Flanges are formed to each of the end edges of the shield boxes and the shield boxes are connected to each other by the flanges. Upon installation, empty shield boxes not charged with lead particles and iron plate shields are secured at first at the periphery of the pipeline. Then, lead particles are charged into the shield boxes. This attains a state as if lead plate corresponding to the depth of the box is disposed. Accordingly, operations for installation, dismantling and restoration can be conducted in an empty state with reduced weight to facilitate the operations. (I.S.)

  8. Lead poisoning in mink

    Energy Technology Data Exchange (ETDEWEB)

    Purdy, J G

    1962-03-01

    This paper describes a case of lead poisoning in minks. The mink were housed in pens which had been painted with a bridge paint containing lead. They had chewed on the pen and ingested the paint. The animals that did not die were moved to new pens, and vitamin D and calcium gluconate were added to their diets. In three days, a marked improvement was seen in the food and water consumption, and convolutions became less frequent.

  9. Enfermedad por depósito de cristales de pirofosfato cálcico en la articulación temporomandibular con extensión intracraneal: A propósito de un caso Calcium pyrophosphate deposition disease of the temporomandibular joint with intracranial extension: A case report

    Directory of Open Access Journals (Sweden)

    I. Zubillaga Rodríguez

    2011-03-01

    Full Text Available Introducción: La articulación temporomandibular (ATM humana es un conjunto de estructuras que permite la relación anatómica y funcional entre el hueso temporal y la mandíbula. Los síntomas y signos asociados a los procesos neoplásicos-seudotumorales de la ATM son similares a los asociados a los trastornos temporomandibulares. Caso clínico: Presentamos un nuevo caso clínico de enfermedad por depósito de cristales de pirofosfato cálcico deshidratado (EDCPCD con afectación de la ATM e invasión intracraneal. Se trata de una artropatía microcristalina que comparte características clínicas con la condromatosis sinovial. Se exponen los aspectos claves relativos al diagnóstico y el tratamiento de dicha patología. Discusión: Los tumores que más frecuentemente afectan la ATM son las metástasis de tumores malignos. Entre las lesiones tumorales-seudotumorales que se originan directamente de la membrana sinovial se encuentran la condromatosis sinovial, la sinovitis villo-nodular, el sarcoma sinovial, la gota tofácea y la EDCPCD. Esta última es relativamente común en edades avanzadas, particularmente en la rodilla. El análisis de los cristales es esencial para establecer un diagnóstico de certeza. El tratamiento es eminentemente quirúrgico. Conclusiones: La EDCPCD en la ATM es extremadamente rara. Las masas tumorales que surgen como tumores primarios en la ATM representan un problema diagnóstico desafiante. La variada presentación de estas lesiones a menudo enmascara la patología de base y conlleva su retraso en el diagnóstico.Introduction: The human temporomandibular joint (TMJ is the structural complex that supports the functional and anatomic relations between the temporal bone and mandible. Symptoms and signs related to neoplastic or pseudotumoral disease of this joint are similar to the symptoms associated with temporomandibular joint dysfunction. Case report: We report a new case of calcium pyrophosphate deposition disease

  10. A contribution to the structural and kinetic study of the slow transformation of an iron or uranium alpha crystal; Contribution a l'etude structurale et cinetique de la transformation lente d'un cristal de fer alpha ou d'uranium alpha

    Energy Technology Data Exchange (ETDEWEB)

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

    1958-12-15

    1- During the course of the work reported, we observed and studied a curious phenomenon of regeneration of an iron or uranium {alpha} crystal in the double transformation of iron or uranium: {alpha} {yields} {gamma} {yields} {alpha} and {alpha} {yields} {beta} {yields} {alpha} respectively. We have demonstrated that this phenomenon does not occur with very pure metals, but only in the case of metals containing impurities, and more particularly, containing carbon. The monocrystal is not regenerated unless care is taken not to exceed final transformation temperatures by more than a few degrees. The same phenomenon is encountered in polycrystalline compounds: the orientation of the crystals is maintained, though the respective grain positions ('joints') are considerably displaced. 2- Kinetic study of the transformation at cooling, on the one hand, and the analysis of the texture at the {gamma} phase (iron) on the other, show that regeneration results from the conservation of the phase {alpha} germs at the high temperature phase. They appear to be relatively stable because they had retained their properties at the end of 24 hours at the experiment temperature. 3- Study of the twin crystals of {gamma} iron engendered by the transformation {alpha} {yields} {gamma} demonstrated that there is no orientation relationship in the transformation: {alpha} {yields} {gamma} of pure iron. 4- Thanks to the production of an epitaxic oxide film on the surface of {gamma} iron, we were able to evidence a new type of iron transformation twinned crystal which grows in one direction (110) and is in contact also at 110. Formed of very thin lamina, these crystals are very instable and become penetrant, each element - much larger - consisting of the increased thickness of a certain number of lamina. (author) [French] 1- Au cours de ce travail, nous avons observe et etudie un curieux phenomene de regeneration d'un cristal unique de fer {alpha} ou d'uranium {alpha} au cours de la double

  11. Lead poisoning in dogs

    International Nuclear Information System (INIS)

    Zook, B.C.; Carpenter, J.L.; Leeds, E.B.

    1969-01-01

    Lead poisoning was diagnosed and studied in 60 dogs. It was found that lead poisoning is a common disease of young dogs, especially in the summer and fall, and is related to their chewing and eating habits resulting in the ingestion of paint, linoleum, or other lead-containing materials. The signs were characterized by gastrointestinal dysfunction (colic, vomiting, and diarrhea) and nervous disorders (convulsions, hysteria, nervousness, behavioral changes). The blood findings, which the authors consider nearly pathognomonic, consisted of numerous stippled and immature (especially nucleated) erythrocytes in the absence of severe anemia. Protein and casts were frequently found in the urine. Radiography sometimes revealed lead-containing particles in the gastro-intestinal tract, and lead lines were occasionally detected in the metaphysis of long bones in immature dogs. Treatment with calcium ethylenediamine-tetraacetic acid resulted in rapid and often dramatic recoveries in nearly all instances. Removal of lead from the gastrointestinal tract and treatment to relieve pronounced central nervous disorders was sometimes necessary. 40 references, 6 figures, 7 tables

  12. The use of steel and lead shieldings in radiotherapy rooms and its comparison with respect to neutrons doses at patients; Comparacao de blindagens de aco e de chumbo usadas em salas de radioterapia quanto a dose devido a neutrons depositada em pacientes

    Energy Technology Data Exchange (ETDEWEB)

    Silva, M.G.; Rebello, W.F.; Andrade, E.R.; Medeiros, M.P.C.; Mendes, R.M.S.; Braga, K.L.; Gomes, R.G., E-mail: maglosilva15@gmail.com, E-mail: rebello@ime.eb.br, E-mail: fisica.dna@gmail.com, E-mail: eng.cavaliere@gmail.com, E-mail: raphaelmsm@gmail.com, E-mail: kelmo.lins@gmail.com, E-mail: ggrprojetos@gmail.com [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil); Santos, R.F.G., E-mail: raphaelfgsantos@gmail.com [Centro Universitario Anhanguera, Niteroi, RJ (Brazil). Departamento de Engenharia; Silva, Ademir X., E-mail: ademir@con.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    The NCRP Report No. 151, Structural Shielding Design and Evaluation for Megavoltage X- and Gamma-Ray Radiotherapy Facilities, considers, in shielding calculations for radiotherapy rooms, the use of lead and/or steel to be applied on bunker walls. The NCRP Report calculations were performed foreseeing a better protection of people outside the radiotherapy room. However, contribution of lead and steel to patient dose should be taken into account for radioprotection purposes. This work presents calculations performed by MCNPX code in analyzing the Ambient Dose Equivalent due to neutron, H*(10){sub n}, within a radiotherapy room, in the patients area, considering the use of additional shielding of 1 TVL of lead or 1 TVL of steel, positioned at the inner faces of walls and ceiling of a bunker. The head of the linear accelerator Varian 2100/2300 C/D was modeled working at 18MeV, with 5x5cm{sup 2}, 10x10cm{sup 2}, 20x20cm{sup 2}, 30x30cm{sup 2} and 40x40cm{sup 2} openings for jaws and MLC and operating in eight gantry's angles. This study shows that the use of lead generates an average value of H*(10){sub n} at patients area, 8.02% higher than the expected when using steel. Further studies should be performed based on experimental data for comparison with those from MCNPX simulation.

  13. Magnesium Diboride Current Leads

    Science.gov (United States)

    Panek, John

    2010-01-01

    A recently discovered superconductor, magnesium diboride (MgB2), can be used to fabricate conducting leads used in cryogenic applications. Dis covered to be superconducting in 2001, MgB2 has the advantage of remaining superconducting at higher temperatures than the previously used material, NbTi. The purpose of these leads is to provide 2 A of electricity to motors located in a 1.3 K environment. The providing environment is a relatively warm 17 K. Requirements for these leads are to survive temperature fluctuations in the 5 K and 11 K heat sinks, and not conduct excessive heat into the 1.3 K environment. Test data showed that each lead in the assembly could conduct 5 A at 4 K, which, when scaled to 17 K, still provided more than the required 2 A. The lead assembly consists of 12 steelclad MgB2 wires, a tensioned Kevlar support, a thermal heat sink interface at 4 K, and base plates. The wires are soldered to heavy copper leads at the 17 K end, and to thin copper-clad NbTi leads at the 1.3 K end. The leads were designed, fabricated, and tested at the Forschungszentrum Karlsruhe - Institut foer Technische Physik before inclusion in Goddard's XRS (X-Ray Spectrometer) instrument onboard the Astro-E2 spacecraft. A key factor is that MgB2 remains superconducting up to 30 K, which means that it does not introduce joule heating as a resistive wire would. Because the required temperature ranges are 1.3-17 K, this provides a large margin of safety. Previous designs lost superconductivity at around 8 K. The disadvantage to MgB2 is that it is a brittle ceramic, and making thin wires from it is challenging. The solution was to encase the leads in thin steel tubes for strength. Previous designs were so brittle as to risk instrument survival. MgB2 leads can be used in any cryogenic application where small currents need to be conducted at below 30 K. Because previous designs would superconduct only at up to 8 K, this new design would be ideal for the 8-30 K range.

  14. Reference pp cross-sections for $\\Upsilon(1S)$ studies in proton-lead collisions at $\\sqrt{s_{NN}} = 5.02$ TeV and comparisons between ALICE and LHCb results

    CERN Document Server

    ALICE and LHCb Collaborations

    2014-01-01

    The ALICE and LHCb collaborations have studied $\\Upsilon$ (1$S$) production at large rapidities in proton-lead collisions at $\\sqrt{s_{NN}} = 5.02$ TeV at the LHC using di-muon fi nal states. The evaluation of cold nuclear matter effects requires the knowledge of the corresponding $\\Upsilon$ (1$S$) production cross section in $pp$ collisions at the same centre-of-mass energy and in the same kinematic range. In this note the interpolation procedures used to determine this quantity and the related consistency checks are described. Finally, the results from the two experiments on nuclear modi fication factors are briefly summarized and found to be in good agreement.

  15. Structure/function relationship of the rusticyanin among thiobacillus ferroxidans: from the fermenter to the crystal; Relations structure/fonction de la rusticyanine chez thiobacillus ferrooxidans: du fermenteur au cristal

    Energy Technology Data Exchange (ETDEWEB)

    Nunzi, F.

    1996-09-23

    The commercial extraction of copper and uranium from ores by microbial leaching turns to account the iron oxidation capacity of Thiobacillus ferroxidans. The iron oxidation involves an electron transport chain localized in the peri-plasmic space of the cell. The aim of our work is to study the structure-function relationships of rusticyanin, the most important component of this respiratory chain. Rusticyanin is a blue copper protein and has been characterized from a new strain of Thilbacillus ferrooxidans. A preliminary electrochemical study has been made with a new modified-gold electrode and we have examined, in particular, the pH dependence of the high redox potential of rusticyanin. Its amino acid sequence has been determined and a comparison with two other rusticyanin sequences, isolated from different strains, shows a high degree of homology. A structural alignment with six other blue copper proteins allows to propose four residues as copper ligands, His 84, Cys 138, His 143 and Met 148. The supposed factors responsible for the high redox potential of rusticyanin are discussed. (author)

  16. Biological fractionation of lead isotopes in Sprague-Dawley rats lead poisoned via the respiratory tract.

    Science.gov (United States)

    Wu, Jing; Liu, Duojian; Xie, Qing; Wang, Jingyu

    2012-01-01

    It was considered that lead isotope ratios did not change during physical, chemical, or biological processes. Thus, lead isotope ratios have been used as fingerprints to identify possible lead sources. However, recent evidence has shown that the lead isotope ratios among different biological samples in human are not always identical from its lead origins in vitro. An animal experiment was conducted to explore the biological fractionation of lead isotopes in biological systems. 24 male Sprague-Dawley (SD) rats were divided into groups that received acute lead exposure (0, 0.02, 0.2, or 2 mg/kg body weight of lead acetate) via the respiratory route every day for 5 days. Biological samples (i.e., blood, urine, and feces) were collected for comparison with the lead acetate (test substance) and the low-lead animal feed (diet) administered to the rats. The lead isotope ratios were determined by inductively coupled plasma mass spectrometry (ICP-MS). There are significant differences (pblood, urine, and feces. Moreover, a nonlinear relationship between the blood lead concentration and the blood lead isotope ratios was observed. There is also a threshold effect to the fractionation function. Only the blood isotope ratio of (204)Pb/(206)Pb matches the test substance well. As for feces, when (204)Pb/(206)Pb ratio is considered, there is no significant difference between feces-test substance pairs in medium and high dose group. The biological fractionation of lead isotopes in SD rats was observed. Moreover, there might be a threshold for the biological fractionation of lead isotopes which is depending on whole blood lead level. It is considered to be more reliable that we compared the isotope ratios of potential lead hazards with both blood and feces lead fingerprints especially for (204)Pb/(206)Pb ratio under high-dose exposure.

  17. Gas cooled leads

    International Nuclear Information System (INIS)

    Shutt, R.P.; Rehak, M.L.; Hornik, K.E.

    1993-01-01

    The intent of this paper is to cover as completely as possible and in sufficient detail the topics relevant to lead design. The first part identifies the problems associated with lead design, states the mathematical formulation, and shows the results of numerical and analytical solutions. The second part presents the results of a parametric study whose object is to determine the best choice for cooling method, material, and geometry. These findings axe applied in a third part to the design of high-current leads whose end temperatures are determined from the surrounding equipment. It is found that cooling method or improved heat transfer are not critical once good heat exchange is established. The range 5 5 but extends over a large of values. Mass flow needed to prevent thermal runaway varies linearly with current above a given threshold. Below that value, the mass flow is constant with current. Transient analysis shows no evidence of hysteresis. If cooling is interrupted, the mass flow needed to restore the lead to its initially cooled state grows exponentially with the time that the lead was left without cooling

  18. Leading healthcare in complexity.

    Science.gov (United States)

    Cohn, Jeffrey

    2014-12-01

    Healthcare institutions and providers are in complexity. Networks of interconnections from relationships and technology create conditions in which interdependencies and non-linear dynamics lead to surprising, unpredictable outcomes. Previous effective approaches to leadership, focusing on top-down bureaucratic methods, are no longer effective. Leading in complexity requires leaders to accept the complexity, create an adaptive space in which innovation and creativity can flourish and then integrate the successful practices that emerge into the formal organizational structure. Several methods for doing adaptive space work will be discussed. Readers will be able to contrast traditional leadership approaches with leading in complexity. They will learn new behaviours that are required of complexity leaders, along with challenges they will face, often from other leaders within the organization.

  19. Induction of heat shock proteins (hsp70) in the zebra mussel (Dreissena polymorpha) following exposure to platinum group metals (platinum, palladium and rhodium): Comparison with lead and cadmium exposures

    Energy Technology Data Exchange (ETDEWEB)

    Singer, Christoph [Zoologisches Institut I-Oekologie, Universitaet Karlsruhe, Geb. 07.01, Kornblumenstrasse 13, D-76131 Karlsruhe (Germany); Zimmermann, Sonja [Zoologisches Institut I-Oekologie, Universitaet Karlsruhe, Geb. 07.01, Kornblumenstrasse 13, D-76131 Karlsruhe (Germany); Sures, Bernd [Zoologisches Institut I-Oekologie, Universitaet Karlsruhe, Geb. 07.01, Kornblumenstrasse 13, D-76131 Karlsruhe (Germany)]. E-mail: dc11@rz.uni-karlsruhe.de

    2005-10-05

    An increasing number of papers concentrate on the availability and uptake of platinum group elements (PGE) by different organisms. These metals are discharged into the environment from different anthropogenic sources, such as automobile catalytic converters, hospitals and other medical institutions. As the effects of these precious metals on organisms remain unclear, the induction of heat shock proteins (hsp70) in zebra mussels (Dreissena polymorpha) following exposure to soluble salts of platinum, palladium and rhodium was compared with the hsp70 induction in mussels following exposure to cadmium and lead. Mussels were sampled weekly during a period of 10 weeks and analyzed for their metal concentration and their hsp70 level. Highest metal uptake was found for Cd, followed by Pt, Pb and Pd. Rh demonstrated the lowest uptake rate. A clear time-dependent increase of hsp70 levels occurred in all exposed mussels. Concentrations of hsp70 started to rise between days 18 and 25, except for the Pt-exposed group, where the initial increase was between days 25 and 32. All groups reached maximal hsp70 concentrations at day 39. Subsequently, hsp70 levels decreased to initial levels for the remaining exposure period. Threshold metal levels for the hsp70 induction varied among the metals and increased in the order: Rh < Pd {<=} Pb < Pt < Cd. Highest hsp70 values were found for mussels exposed to Pd, with a 25-fold higher level than in the controls, followed by Pt- and Rh-exposed mussels, which showed a 19-fold increase. The hsp70 levels of the mussels exposed to Cd and Pb were much lower, showing 6- and 12-fold higher values than the control, respectively. The clear induction of hsp70 due to exposure to Pt, Pd and Rh gives evidence for strong cellular effects of these metals, especially, when compared with lead and cadmium. Among the metals tested, Pd seems to have the highest potential as inducer for hsp70 production due to its low threshold level in combination with the

  20. Induction of heat shock proteins (hsp70) in the zebra mussel (Dreissena polymorpha) following exposure to platinum group metals (platinum, palladium and rhodium): Comparison with lead and cadmium exposures

    International Nuclear Information System (INIS)

    Singer, Christoph; Zimmermann, Sonja; Sures, Bernd

    2005-01-01

    An increasing number of papers concentrate on the availability and uptake of platinum group elements (PGE) by different organisms. These metals are discharged into the environment from different anthropogenic sources, such as automobile catalytic converters, hospitals and other medical institutions. As the effects of these precious metals on organisms remain unclear, the induction of heat shock proteins (hsp70) in zebra mussels (Dreissena polymorpha) following exposure to soluble salts of platinum, palladium and rhodium was compared with the hsp70 induction in mussels following exposure to cadmium and lead. Mussels were sampled weekly during a period of 10 weeks and analyzed for their metal concentration and their hsp70 level. Highest metal uptake was found for Cd, followed by Pt, Pb and Pd. Rh demonstrated the lowest uptake rate. A clear time-dependent increase of hsp70 levels occurred in all exposed mussels. Concentrations of hsp70 started to rise between days 18 and 25, except for the Pt-exposed group, where the initial increase was between days 25 and 32. All groups reached maximal hsp70 concentrations at day 39. Subsequently, hsp70 levels decreased to initial levels for the remaining exposure period. Threshold metal levels for the hsp70 induction varied among the metals and increased in the order: Rh < Pd ≤ Pb < Pt < Cd. Highest hsp70 values were found for mussels exposed to Pd, with a 25-fold higher level than in the controls, followed by Pt- and Rh-exposed mussels, which showed a 19-fold increase. The hsp70 levels of the mussels exposed to Cd and Pb were much lower, showing 6- and 12-fold higher values than the control, respectively. The clear induction of hsp70 due to exposure to Pt, Pd and Rh gives evidence for strong cellular effects of these metals, especially, when compared with lead and cadmium. Among the metals tested, Pd seems to have the highest potential as inducer for hsp70 production due to its low threshold level in combination with the

  1. Comparison of psychosexual problems between substance dependence patients

    Directory of Open Access Journals (Sweden)

    Hamid Kazami

    2014-06-01

    Full Text Available Background and aims: Sexual dissatisfaction is one of the common problems in patients of Substance dependency. The aim of this study was to investigate psychosexual problems in marital relationships in substance dependence patients: Crack, Cristal and Opium and compare with control group. Methods: In this descriptive-analytic study, 56 substance dependences referred to addiction treatment center were selected by convenience sampling and assigned to four groups: 20 Opium consumers, 18 on Crack, 18 on Cristal and 20 patients in control group. The Multidimensional Sexuality Questionnaires (MSQ were completed by participants. Results: Based on subscales of Multidimensional Sexuality Questionnaire, a significant difference was observed in score mean among three groups and between experimental groups and control group in sexual subscales: preoccupation, motivation, assertiveness, depression, monitoring power of other sex, sexual control, external supervision, fear of sexual relationship and satisfaction (P>0.05. Differences between (Cristal and Crack and (Opium and Cristal in sexual subscales: preoccupation, motivation, fear, depression, power-other sexual control, supervision, and fear of sexual relationship and satisfaction were significant (P>0.05. Score mean indicated that the Cristal abusers in all of subscales have higher scores mean than Crack, and Opium. Conclusion: According to the results of current study, the available addicting substance in the market affects the consumer's sexual practices, and will be caused deleterious effects on family and marital sexual health.

  2. Investigation into the structure of lead-borate glass

    International Nuclear Information System (INIS)

    Kurtsinovskaya, R.I.

    1976-01-01

    X-ray phase and IR analysis of lead borate glasses show that glasses containing from 12 to 45 mole % PbO consist of several phases. A comparison of x-ray different data for lead borate and lead germanate glasses, which have two maxima on the diffraction patterns throughout the glass-formation region, shows that the microstructure of lead borate glasses is far more complex

  3. Relational Perspectives on Leading

    DEFF Research Database (Denmark)

    Relational Perspectives on Leading discusses leadership from a relational and social constructionism perspective as practiced on an everyday basis between people. The book pursues a fast growing, practice-based approach - particularly within the Anglo-Saxon parts of the world - to organization...

  4. Learn about Lead

    Science.gov (United States)

    ... Search Main menu Environmental Topics Air Bed Bugs Chemicals and Toxics Environmental Information by Location Greener Living Health Land, ... it has some beneficial uses, it can be toxic to humans and animals causing of health ... some types of industrial facilities, and past use of lead-based paint ...

  5. Leading Causes of Blindness

    Science.gov (United States)

    ... have cataracts. They are the leading cause of blindness in the world. By age 80, more than half of all people in the United States either will have a cataract or have had cataract surgery. Common symptoms are: Blurry vision Colors that seem faded Glare Not being able to ...

  6. Lead User Innovation

    DEFF Research Database (Denmark)

    Brem, Alexander; Larsen, Henry

    2015-01-01

    covers the opposite view, where a company actively searches and involves lead users, however, with limited success also. Based on both cases, we analyze how, in these emerging processes of relating, meaning is co-created in a way that narrows the shared conceptual space for imagination and collaboration...

  7. Girls Leading Outward

    Science.gov (United States)

    Hamed, Heather; Reyes, Jazmin; Moceri, Dominic C.; Morana, Laura; Elias, Maurice J.

    2011-01-01

    The authors describe a program implemented in Red Bank Middle School in New Jersey to help at-risk, minority middle school girls realize their leadership potential. The GLO (Girls Leading Outward) program was developed by the Developing Safe and Civil Schools Project at Rutgers University and is facilitated by university students. Selected middle…

  8. Leading through Conflict

    Science.gov (United States)

    Gerzon, Mark

    2006-01-01

    This article talks about leading significant learning opportunities through conflict of ideas in a school system. Catalyzing school change can turn emotional differences of opinion into learning opportunities. Leaders who want to deal effectively with these challenging, often tense situations need to be more than good managers. They need to be…

  9. Lead Time Study,

    Science.gov (United States)

    1982-05-01

    1979, the number of titanium fabrications dropped from 16 to 4, primarily because of the sponge shortage and EPA and OSHA requirements. Non-military...East - Taiwan, Korea, Singapore, Malaysia and Hong Kong. In addition, a significant amount of ceramic parts, lead frames and high technology

  10. Lead pollution in Islamabad

    International Nuclear Information System (INIS)

    Mohammad, D.; Khatoon, N.; Ishaque, M.; Ahmed, I.

    1997-01-01

    Lead pollution of urban area emanating from the vehicular exhaust alone is being labeled as one of the worst form of environmental degradation attracting our attention for remediation. For factual assessment samples were collected from different areas of Islamabad. These samples consisted of tree scrapings / peelings, which were dried and ground before undertaking analysis for the lead content. The samples were digested with an acid mixture to remove the organic matter and analyzed using GFAAS technique. A total of 81 samples have been analyzed. The results sowed a lead content varying in the range of 8-474 Mu g g/sup -1/) and 23 samples with Pb content <50 Mu g g-1 (8.0-50.0 Mu g g/sup -1/). Most of the samples also contained some growth which consisted of bacterial, algae and fugal cells and the results have been explained on the basis of Pb absorption by these cells. The procedure followed in this study is recommended for evaluation of lead pollution in urban areas. (author)

  11. EFFECT OF LEAD ACETATE

    African Journals Online (AJOL)

    MICROSOFT

    increase in the production of poultry meat at a reasonable cost (Alam et al., ...... 36(4): 537-541. Taggart MA, Figuerola J, Green AJ, Mateo R, Deacon C, Osborn D, ... selenium, lead and copper levels in the livers and bones of five waterfowl ...

  12. Intoxication for lead

    International Nuclear Information System (INIS)

    Velez, Ruben Dario; Tamayo, Margarita Maria

    1999-01-01

    We present a case of a hospitalized girl with bronchopneumonia, who needed mechanic ventilation. Also she had a developmental delay and Burtons border in gums. Radiological studies showed dense transverse metaphiseal bands in long bones and hyperdensity in basal ganglia. We found high serum lead levels

  13. Lead Thickness Measurements

    International Nuclear Information System (INIS)

    Rucinski, R.

    1998-01-01

    The preshower lead thickness applied to the outside of D-Zero's superconducting solenoid vacuum shell was measured at the time of application. This engineering documents those thickness measurements. The lead was ordered in sheets 0.09375-inch and 0.0625-inch thick. The tolerance on thickness was specified to be +/- 0.003-inch. The sheets all were within that thickness tolerance. The nomenclature for each sheet was designated 1T, 1B, 2T, 2B where the numeral designates it's location in the wrap and 'T' or 'B' is short for 'top' or 'bottom' half of the solenoid. Micrometer measurements were taken at six locations around the perimeter of each sheet. The width,length, and weight of each piece was then measured. Using an assumed pure lead density of 0.40974 lb/in 3 , an average sheet thickness was calculated and compared to the perimeter thickness measurements. In every case, the calculated average thickness was a few mils thinner than the perimeter measurements. The ratio was constant, 0.98. This discrepancy is likely due to the assumed pure lead density. It is not felt that the perimeter is thicker than the center regions. The data suggests that the physical thickness of the sheets is uniform to +/- 0.0015-inch.

  14. Anatomy of lead poisoning

    African Journals Online (AJOL)

    ABEOLUGBENGAS

    Results: The primary form of lead toxicity is by oxidative stress mechanisms, apoptosis and necrosis involving ... néfastes sur la reproduction à l'avenir. Résultats:La forme ... prostate cancers, abnormal sexual ..... ensure this work is a success.

  15. Scientometry Leading us Astray

    Czech Academy of Sciences Publication Activity Database

    Haindl, Michal

    2010-01-01

    Roč. 2010, č. 82 (2010), s. 8-8 ISSN 0926-4981 Institutional research plan: CEZ:AV0Z10750506 Keywords : scientometry Subject RIV: BD - Theory of Information http://ercim-news.ercim.eu/en82/european-scene/ scientometry -leading-us-astray

  16. Total contribution of airborne lead to blood lead.

    OpenAIRE

    Manton, W I

    1985-01-01

    A nine year study of blood lead concentrations and isotope ratios carried out on a married couple shows that pulmonary deposition cannot account for all the airborne lead in blood; that lead from bone may comprise 70% of blood lead; and that during pregnancy blood lead may double due to mobilisation of lead from bone.

  17. Total contribution of airborne lead to blood lead.

    Science.gov (United States)

    Manton, W I

    1985-01-01

    A nine year study of blood lead concentrations and isotope ratios carried out on a married couple shows that pulmonary deposition cannot account for all the airborne lead in blood; that lead from bone may comprise 70% of blood lead; and that during pregnancy blood lead may double due to mobilisation of lead from bone. PMID:3970881

  18. Comparison of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in feathers in bald eagle (Haliaeetus leucocephalus), and comparison with common eider (Somateria mollissima), glaucous-winged gull (Larus glaucescens), pigeon guillemot (Cepphus columba), and tufted puffin (Fratercula cirrhata) from the Aleutian Chain of Alaska

    Science.gov (United States)

    Burger, Joanna; Gochfeld, Michael

    2014-01-01

    There is an abundance of field data for levels of metals from a range of places, but relatively few from the North Pacific Ocean and Bering Sea. In this paper we examine the levels of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in feathers from common eiders (Somateria mollissima), glaucous-winged gulls (Larus glaucescens), pigeon guillemots (Cepphus columba), tufted puffins (Fratercula cirrhata) and bald eagles (Haliaeetus leucocephalus) from the Aleutian Chain of Alaska. Our primary objective was to test the hypothesis that there are no trophic levels relationships for arsenic, cadmium, chromium, lead, manganese, mercury and selenium among these five species of birds breeding in the marine environment of the Aleutians. There were significant interspecific differences in all metal levels. As predicted bald eagles had the highest levels of arsenic, chromium, lead, and manganese, but puffins had the highest levels of selenium, and pigeon guillemot had higher levels of mercury than eagles (although the differences were not significant). Common eiders, at the lowest trophic level had the lowest levels of some metals (chromium, mercury and selenium). However, eiders had higher levels than all other species (except eagles) for arsenic, cadmium, lead, and manganese. Levels of lead were higher in breast than in wing feathers of bald eagles. Except for lead, there were no significant differences in metal levels in feathers of bald eagles nesting on Adak and Amchitka Island; lead was higher on Adak than Amchitka. Eagle chicks tended to have lower levels of manganese than older eagles. PMID:18521716

  19. Effects of lead on plant growth

    Energy Technology Data Exchange (ETDEWEB)

    Fiussello, N.; Molinari, M.T.

    1973-01-01

    The poisonousness of lead nitrate to seedlings of several plant species has been tested in Petri dishes, with 10/sup -1/, 10/sup -2/, 10/sup -3/, 10/sup -4/ M conc. Distilled water and KNO/sub 3/ solutions 2 X 10/sup -1/, 2 X 10/sup -2/, 2 X 10/sup -3/, 2 X 10/sup -4/ M were employed as controls. The tested species show a decreasing sensitivity: Capsicum annum > Beta vulgaris > Phalaris canariensis > Vicia sativa > Helianthus annuus > Oryza sativa > Triticum vulgare Avena sativa > Pisum sativum. Avena sativa shows a diminution of 34% in ww, 23% in dw, 26% in chlorophyll content in comparison with the controls after 21 days 10/sup -4/ M lead nitrate. The chlorophyll content, referred to dry weight, is related to lead concentration. Since the early stages of chlorophyll biosynthesis are similar, if not identical, with those for Haemoglobin, lead could interfere as it does in haemoglobin synthesis.

  20. Safety and Health Topics: Lead

    Science.gov (United States)

    ... ammunition, pipes, cable covering, building material, solder, radiation shielding, collapsible tubes, and fishing weights. Lead is also ... lead linings in tanks and radiation protection, leaded glass, work involving soldering, and other work involving lead ...

  1. [Comparison of film-screen combinations in contrast-detail diagram and with interactive image analysis. 3: Trimodal histograms of gray scale distribution in bar groups of lead pattern images].

    Science.gov (United States)

    Hagemann, G; Eichbaum, G; Stamm, G

    1998-05-01

    The following four screen film combinations were compared: a) a combination of anticrossover film and UV-light emitting screens, b) a combination of blue-light emitting screens and film and c) two conventional green fluorescing screen film combinations. Radiographs of a specially designed plexiglass phantom (0.2 x 0.2 x 0.12 m3) with bar patterns of lead and plaster and of air, respectively were obtained using the following parameters: 12 pulse generator, 0.6 mm focus size, 4.7 mm aluminum prefilter, a grid with 40 lines/cm (12:1) and a focus-detector distance of 1.15 m. Image analysis was performed using an Ibas system and a Zeiss Kontron computer. Display conditions were the following: display distance 0.12 m, a vario film objective 35/70 (Zeiss), a video camera tube with a PbO photocathode, 625 lines (Siemens Heimann), an Ibas image matrix of 512 x 512 pixels with a spatial resolution of ca. 7 cycles/mm, the projected matrix area was 5000 micron 2. Maxima in the histograms of a grouped bar pattern were estimated as mean values from the bar and gap regions ("mean value method"). They were used to calculate signal contrast, standard deviations of the means and scatter fraction. Comparing the histograms with respect to spatial resolution and kV setting a clear advantage of the UVR system becomes obvious. The quantitative analysis yielded a maximum spatial resolution of approx. 3 cycles/mm for the UVR system at 60 kV which decreased to half of this value at 117 kV caused by the increasing influence of scattered radiation. A ranking of screen-film systems with respect to image quality and dose requirement is presented. For its evaluation an interactive image analysis using the mean value method was found to be superior to signal/noise ratio measurements and visual analysis in respect to diagnostic relevance and saving of time.

  2. Comparison of screen film combinations: results of a contrast detail study and interactive image quality analysis. Pt. III. Trimodal histograms of grey-value distributions found in the images of grouped lead bar pattern

    International Nuclear Information System (INIS)

    Hagemann, G.; Eichbaum, G.; Stamm, G.

    1998-01-01

    The following four screen film combinations were compared: (a) a combination of anticrossover film and UV-light emitting screens, (b) a combination of blue-light emitting screens and film and (c) two conventional green fluorescing screen film combinations. Radiographs of a specially designed plexiglass phantom (0.2 x 0.2 x 0.12 m 3 ) with bar patterns of lead and plaster and of air, respectively were obtained using the following parameters: 12 pulse generator, 0.6 mm focus size, 4.7 mm aluminum prefilter, a grid with 40 lines/cm (12:1) and a focus-detector distance of 1.15 m. Image analyses was performed using an Ibas system and a Zeiss Kontron computer. Display conditions were the following: display distance 0.12 m, a vario film objective 35/70 (Zeiss), a video camera tube with a PbO photocathode, 625 lines (Siemens Heimann), an Ibas image matrix of 512 x 512 pixels with a spatial resolution of ca. 7 cycles/mm, the projected matrix area was 5000 μm 2 . Maxima in the histograms of a grouped bar pattern were estimated as mean values from the bar and gap regions ('mean value method'). They were used to calculate signal contrast, standard deviations of the means and scatter fraction. Comparing the histograms with respect to spatial resolution and kV setting a clear advantage of the UVR system becomes obvious. The quantitative analysis yielded a maximum spatial resolution of approx. 3 cycles/mm for the UVR system at 60 kV which decreased to half of this value at 117 kV caused by the increasing influence of scattered radiation. A ranking of screen-film systems with respect to image quality and dose requirement is presented. For its evaluation an interactive image analysis using the mean value method was found to be superior to signal/noise ratio measurements and visual analysis in respect to diagnostic relevance and saving of time. (orig./MG) [de

  3. Lead poisoning: The invisible disease

    Science.gov (United States)

    Friend, Milton

    1989-01-01

    Lead poisoning is an intoxication resulting from absorption of hazardous levels of lead into body tissues. Lead pellets from shot shells, when ingested, are the most common source of lead poisoning in migratory birds. Other far less common sources include lead fishing sinkers, mine wastes, paint pigments, bullets, and other lead objects that are swallowed.

  4. Lead toxicity: current concerns.

    OpenAIRE

    Goyer, R A

    1993-01-01

    Over the 20-year period since the first issue of Environmental Health Perspectives was published, there has been considerable progress in the understanding of the potential toxicity of exposure to lead. Many of these advances have been reviewed in published symposia, conferences, and review papers in EHP. This brief review identifies major advances as well as a number of current concerns that present opportunities for prevention and intervention strategies. The major scientific advance has be...

  5. CMS lead tungstate crystals

    CERN Multimedia

    Laurent Guiraud

    2000-01-01

    These crystals are made from lead tungstate, a crystal that is as clear as glass yet with nearly four times the density. They have been produced in Russia to be used as scintillators in the electromagnetic calorimeter on the CMS experiment, part of the LHC project at CERN. When an electron, positron or photon passes through the calorimeter it will cause a cascade of particles that will then be absorbed by these scintillating crystals, allowing the particle's energy to be measured.

  6. Leading change: 3--implementation.

    Science.gov (United States)

    Kerridge, Joanna

    The potential for all staff to contribute to service improvement, irrespective of discipline, role or function, is outlined in the 2011 NHS leadership framework. This advocates developing the skills of the entire workforce to create a climate of continuous service improvement. As nurses are often required to take the lead in managing change in clinical practice, this final article in a three-part series focuses on implementing ande potentia reviewing change.

  7. Comparison of crude and adjusted mortality rates from leading causes of death in northeastern Brazil Comparación de las tasas de mortalidad bruta y ajustada debida a las principales causas de muerte en el nordeste del Brasil

    Directory of Open Access Journals (Sweden)

    Elisabeth França

    2012-04-01

    Full Text Available OBJECTIVE: To present how the adjustment of incompleteness and misclassification of causes of death in the vital registration (VR system can contribute to more accurate estimates of the risk of mortality from leading causes of death in northeastern Brazil. METHODS: After estimating the total numbers of deaths by age and sex in Brazil's Northeast region in 2002-2004 by correcting for undercount in the VR data, adjustment algorithms were applied to the reported cause-of-death structure. Average anual age-standardized mortality rates were computed by cause, with and without the corrections, and compared to death rates for Brazil's South region after adjustments for potential misdiagnosis. RESULTS: Death rates from ischemic heart disease, lower respiratory infections, chronic obstructive pulmonary disease, and perinatal conditions were more than 100% higher for both sexes than what was suggested by the routine VR data. Corrected cause-specific mortality rates were higher in the Northeast region versus the South region for the majority of causes of death, including several noncommunicable conditions. CONCLUSIONS: Failure to adjust VR data for undercount of cases reported and misdiagnoses will cause underestimation of mortality risks for the populations of the Northeast region, which are more vulnerable than those in other regions of the country. In order to more reliably understand the pattern of disease, all cause-specific mortality rates in poor populations should be adjusted.OBJETIVO: Presentar de qué manera el ajuste de los datos incompletos y de la clasificación errónea de las causas de muerte registradas en el sistema del registro civil puede ayudar a estimar los riesgos de mortalidad debida a las principales causas de muerte en el nordeste del Brasil. MÉTODOS: Después de calcular el número total de defunciones por edad y sexo en el nordeste del Brasil entre 2002 y 2004 mediante la corrección del subregistro de los datos del registro

  8. Effect on blood lead of airborne lead particles characterized by size.

    Science.gov (United States)

    Park, Dong-Uk; Paik, Nam-Won

    2002-03-01

    Worker exposure to airborne lead particles was evaluated for a total of 117 workers in 12 work-places of four different industrial types in Korea. The particle sizes were measured using 8-stage cascade impactors worn by the workers. Mass median aerodynamic diameters (MMAD) were determined by type of industry and percentage of lead particles as a fraction of airborne lead (PbA) concentration was determined by particle size. Blood lead (PbB) levels of workers who matched airborne lead samples were also examined. A Scheffé's pairwise comparison test showed that MMAD and the fractions of each of respirable particles and lead particles lead particles lead particles (r = 0.82) than that between concentrations of small particles and PbA (r = 0.61). A simple linear regression indicated that PbB correlated better with respirable lead concentration (r2 = 0.35, P = 0.0001) than with PbA concentration and had a higher slope coefficient. Controlling for respirable lead concentration reduced the partial correlation coefficient between PbA concentration and PbB level from 0.56 to 0.20 (P = 0.053). The results indicate that the contribution of respirable lead particles to lead absorption would be greater than that of PbA. This study concludes that the measurement of PbA only may not properly reflect a worker's exposure to lead particles with diverse characteristics. For the evaluation of a worker's exposure to various types of lead particles, it is recommended that respirable lead particles as well as PbA be measured.

  9. Recent Methods in Crystal Spectrometry; Methodes Recentes de Spectrometrie a Cristal; 041d 041e 0412 042b 0415 041c 0415 0422 041e 0414 042b 041a 0420 0418 0421 0422 0410 041b 041b 0418 0427 0415 0421 041a 041e 0419 0421 041f 0415 041a 0422 0420 041e 041c 0415 0422 0420 0418 0418 ; Metodos Recientes de Espectrometria Cristalina

    Energy Technology Data Exchange (ETDEWEB)

    Iyengar, P. K. [Atomic Energy Establishment Trombay, Bombay (India)

    1965-06-15

    measurements of energy distribution is illustrated. A further advantage in the study of single crystal samples comes from the possibility-of operating all the arms with the analysing spectrometers in the constant-Q mode. This would, in future, greatly increase the rate of data collection using the crystal spectrometer technique. (author) [French] Le principe de la diffraction dans les cristaux fournit un moyen, simple de mesurer la distribution des neutrons lents selon l'energie. Toutefois, la determination quantitative de cette distribution depend de parametres differents selon la structure de la cellule elementaire du cristal monochromateur et la disposition geometrique du spectrometre. Le spectrometre triaxial a ete beaucoup utilise dans des travaux sur la diffusion inelastique.. Il comporte un cristal monochromateur et un analyseur a cristal. La disposition geometrique et la dispersion due a la variation non lineaire de l'angle en fonction de la longueur d'onde entrainent des effets de focalisation. L'auteur examine cet aspect du probleme pour divers cas, tels que la diffraction elastique et les groupes de neutrons dus a des interactions a un phonon. L'auteur a utilise comme analyseur un ensemble comprenant un filtre polycristallin et un detecteur, ce qui permet de realiser un gain en intensite dans les mesures de diffusion inelastique. Une des difficultes que presente l'emploi de cet ensemble avec des echantillons a diffusion coherente reside dans l'incertitude relative au transfert de la quantite de mouvement. On a utilise recemment, pour l'etude de la diffusion inelastique, une combinaison de deux filtres de caracteristiques differentes, et un compteur destine a detecter les neutrons retrodiffusis a partir du deuxieme filtre formant fenetre. Ils en resulte un meilleur pouvoir de resolution en energie et une meilleure definition du transfert de la quantite de mouvement. L'auteur presente certaines mesures qui portent sur les caracteristiques de ce type de filtre. Tirant

  10. Lead diffusion in monazite

    International Nuclear Information System (INIS)

    Gardes, E.

    2006-06-01

    Proper knowledge of the diffusion rates of lead in monazite is necessary to understand the U-Th-Pb age anomalies of this mineral, which is one of the most used in geochronology after zircon. Diffusion experiments were performed in NdPO 4 monocrystals and in Nd 0.66 Ca 0.17 Th 0.17 PO 4 polycrystals from Nd 0.66 Pb 0.17 Th 0.17 PO 4 thin films to investigate Pb 2+ + Th 4+ ↔ 2 Nd 3+ and Pb 2+ ↔ Ca 2+ exchanges. Diffusion annealings were run between 1200 and 1500 Celsius degrees, at room pressure, for durations ranging from one hour to one month. The diffusion profiles were analysed using TEM (transmission electronic microscopy) and RBS (Rutherford backscattering spectroscopy). The diffusivities extracted for Pb 2+ + Th 4+ ↔ 2 Nd 3+ exchange follow an Arrhenius law with parameters E equals 509 ± 24 kJ mol -1 and log(D 0 (m 2 s -1 )) equals -3.41 ± 0.77. Preliminary data for Pb 2+ ↔ Ca 2+ exchange are in agreement with this result. The extrapolation of our data to crustal temperatures yields very slow diffusivities. For instance, the time necessary for a 50 μm grain to lose all of its lead at 800 Celsius degrees is greater than the age of the Earth. From these results and other evidence from the literature, we conclude that most of the perturbations in U-Th-Pb ages of monazite cannot be attributed to lead diffusion, but rather to interactions with fluids. (author)

  11. lead glass brick

    CERN Multimedia

    When you look through the glass at a picture behind, the picture appears raised up because light is slowed down in the dense glass. It is this density (4.06 gcm-3) that makes lead glass attractive to physicists. The refractive index of the glass is 1.708 at 400nm (violet light), meaning that light travels in the glass at about 58% its normal speed. At CERN, the OPAL detector uses some 12000 blocks of glass like this to measure particle energies.

  12. Leading change: 2--planning.

    Science.gov (United States)

    Kerridge, Joanna

    National initiatives have outlined the importance of involving frontline staff in service improvement, and the ability to influence and manage change has been identified as an essential skill for delivering new models of care. Nurses often have to take the lead in managing change in clinical practice. The second in a three-part series is designed to help nurses at all levels develop the knowledge and skills to function as change agents within their organisations. This article focuses on planning the change and dealing with resistance.

  13. Leading Change, Adding Value.

    Science.gov (United States)

    Evans, Nick

    2016-09-12

    Essential facts Leading Change, Adding Value is NHS England's new nursing and midwifery framework. It is designed to build on Compassion in Practice (CiP), which was published 3 years ago and set out the 6Cs: compassion, care, commitment, courage, competence and communication. CiP established the values at the heart of nursing and midwifery, while the new framework sets out how staff can help transform the health and care sectors to meet the aims of the NHS England's Five Year Forward View.

  14. Turning lead into gold

    DEFF Research Database (Denmark)

    Jensen, Steffen Moltrup Ernø

    For years the field of entrepreneurship has been blinded by the alchemical promise of turning lead into gold, of finding the ones most likely to become the next Branson, Zuckerberg or Gates. The promise has been created in the midst of political and scientific agendas where certain individuals...... is not to accumulate state or market wealth, but for entrepreneurial skills to become tools towards the liberation of the individual from oppressive systems of control – essentially to add public value rather than economic value. In this presentation I will sketch an anarchist perspective on entrepreneurship, looking...

  15. Remediation of lead contaminated soil

    International Nuclear Information System (INIS)

    Urban, W.; Krishnamurthy, S.

    1992-01-01

    Lead contaminated soil in urban area is of major concern because of the potential health risk to children. Many studies have established a direct correlation between lead in soil and elevated blood lead levels in children. In Minneapolis, Minnesota, Mielke et al. (1983) reported that 50% of the Hmong children with lead poisioning were in areas where soil lead levels were between 500 and 1000 micrograms per gram (ug/g), and 40% of the children suffering from lead poisioning lived in areas where soil lead levels exceeded 1000 ug/g. In urban areas, lead pollution in soil has come from many different sources. The sources include lead paint, lead batteries and automobile exhaust. Olson and Skogerbee (1975) found the following lead compounds in soils where the primary source of pollution was from automobiles: lead sulfate, lead oxide, lead dioxide, lead sulfide, and metallic lead. The primary form of lead found was lead sulfate. Lead sulfate, lead tetraoxide, white lead, and other forms of lead have been used in the manufacture of paints for houses. At present, two remediation techniques, solidification and Bureau of Mines fluosilicic acid leaching, are available for lead-contaminated sites. The objective of the present investigation at the Risk Reduction Engineering Laboratory (RREL), Edison, was to try to solubilize the lead species by appropriate reagents and then recover the contaminants by precipitation as lead sulfate, using environmentally acceptable methods. The apparatus used for mixing was a LabMaster mixer, with variable speed and high-shear impeller. Previous work had used nitric acid for dissolving metallic lead. Owing to the environmental concerns, it was decided to use acetic acid in the presence of oxygen. The theoretical justification for this approach is the favorable redox potential for the reaction between metallic lead, acetic acid, and gaseous oxygen

  16. The optimum lead thickness for lead-activation detectors

    International Nuclear Information System (INIS)

    Si Fenni; Hu Qingyuan

    2009-01-01

    The optimum lead thickness for lead-activation detectors has been studied in this paper. First existence of the optimum lead thickness is explained theoretically. Then the optimum lead thickness is obtained by two methods, MCNP5 calculation and mathematical estimation. At last factors which affect the optimum lead thickness are discussed. It turns out that the optimum lead thickness is irrelevant to incident neutron energies. It is recommended 2.5 cm generally.

  17. Who will lead?

    Science.gov (United States)

    Gustafson, R P; Schlosser, J R

    1997-01-01

    A recent survey conducted by the UCLA Center for Health Services Management and the Physician Executive Practice of Heidrick & Struggles, an executive search firm, sheds light on the emerging physician executive's role. The goal of the research was to identify success factors as a means of evaluating and developing effective industry leaders. Respondents were asked to look at specific skills in relation to nine categories: Communication, leadership, interpersonal skills, self-motivation/management, organizational knowledge, organizational strategy, administrative skills, and thinking. Communication, leadership, and self-motivation/management emerged, in that order, as the three most important success factors for physician executives. An individual's general competencies, work styles, and ability to lead others through organizational restructuring defines his or her appropriateness for managerial positions in the health care industry.

  18. Pulse-form discrimination in organic scintillation crystals; Discrimination d'apres la forme de l'impulsion dans les cristaux organiques de scintillation; Diskriminatsiya formy impul'sov v organicheskikh stsintillyatsionnykh kristallakh; Discriminacion de la forma de los impulsos en los cristales de compuestos organicos para contadores de centelleo

    Energy Technology Data Exchange (ETDEWEB)

    De Vries, L J; Udo, F [Instituut voor Kernphysisch Onderzoek, Amsterdam (Netherlands)

    1962-04-15

    ) [Spanish] Los autores presentan un circuito de discriminacion proton-electron basado en las diferencias de forma entre los impulsos de centelleo luminosos producidos por los protones y por los electrones, respectivamente, en los cristales de estilbeno. El circuito es estable y es capaz de distinguir los impulsos de protones de los electrones hasta con energias de protones de solamente 300 keV. El circuito discriminador, compuesto unicamente de elementos lineales, es sensible a errores inducidos por apilonamiento durante 0,1 {mu}s solamente, a partir de la llegada de un impulso. El circuito descrito se aplico en un espectrometro para neutrones de 1 a 30 MeV, basado en el retroceso de protones entre dos cristales de estilbeno. Se alcanzo un poder de resolucion de 10 por ciento, para una energia neutronica de 14 MeV, con un rendimiento de deteccion de 1,3 {center_dot} 10{sup -4}. Se podria usar un monitor neutronico basado tambien en un sistema de discriminacion lineal de la forma de los impulsos para medir una dosis neutronica igual al 10% de la dosis maxima admisible, en presencia de un flujo {gamma} cuatro veces mayor que la dosis maxima admisible. (author) [Russian] Opisyvaetsya kontur diskriminatsii protonov-ehlektronov, osnovannyj na raznitse formy stsintillyatsionnykh svetovykh impul'sov, navedennykh v stil'bene sootvetstvenno protonami i ehlektronami. EHtot kontur ustojchiv i otlichaet impul'sy protonov ot impul'sov ehlektronov dazhe pri padenii ehnergii protonov do 300 kehv. Diskriminiruyushchij kontur, sostoyashchij isklyuchitel'no iz linejnykh ehlementov, chuvstvitelen k obrazuyushchimsya iz-za nakopleniya oshibkam tol'ko v techenie 0,1 mikro-sekundy posle postupleniya impul'sa. Opisyvaemyj kontur byl ispol'zovan v spektrometre dlya nejtronov s ehnergiyami 1-30 mehv, osnovannom na otdache protonov mezhdu dvumya kristallami stil'bena. Pri ehnergii nejtronov v 14 mehv bylo polucheno ikh razreshenie s tochnost'yu do 10%, pri ehffektivnosti detektirovaniya v 1,3 x 10

  19. Lead and lead-based alloys as waste matrix materials

    International Nuclear Information System (INIS)

    Arustamov, A.E.; Ojovan, M.I.; Kachalov, M.B.

    1999-01-01

    Metals and alloys with relatively low melting temperatures such as lead and lead-based alloys are considered in Russia as prospective matrices for encapsulation of spent nuclear fuel in containers in preparation for final disposal in underground repositories. Now lead and lead-based alloys are being used for conditioning spent sealed radioactive sources at radioactive waste disposal facilities

  20. A Relative Comparison of Leading Supply Chain Management Software Packages

    OpenAIRE

    Zhongxian Wang; Ruiliang Yan; Kimberly Hollister; Ruben Xing

    2009-01-01

    Supply Chain Management (SCM) has proven to be an effective tool that aids companies in the development of competitive advantages. SCM Systems are relied on to manage warehouses, transportation, trade logistics and various other issues concerning the coordinated movement of products and services from suppliers to customers. Although in today’s fast paced business environment, numerous supply chain solution tools are readily available to companies, choosing the right SCM software is not an e...

  1. Lead poisoning in calves

    Energy Technology Data Exchange (ETDEWEB)

    Reeves, J E

    1964-01-01

    Over a three-year period a farmer lost seven calves in their second month of age. One year ago a tentative diagnosis of rabies was given and a brain was submitted to the Health of Animals Division for examination. No Negri bodies were found. The owner stated that the calves first appeared listless and later exhibited severe nervous signs. Deaths occurred in from one to 24 hours after onset of signs. Appetite and bowel movements were normal. There was no increase in temperature. The calf would lie quietly for an interval, then rise, run down the alley, press against a wall, and go into a convulsion. It acted as if it were in severe pain and during one of the intermittent convulsions, it jumped over a three-foot partition. This calf was sent to the Regional Veterinary Laboratory at Brighton for necropsy. The calf had been dead for 72 hours when submitted to the laboratory. The only gross findings were of mild pleurisy and hemorrhage on the kidney. A tentative diagnosis of lead poisoning was offered and specimens sent to the Division of Pharmacology and Toxicology, Ontario Veterinary College.

  2. Drowning: a leading killer!

    Directory of Open Access Journals (Sweden)

    Nuno Domingos Garrido

    2016-10-01

    Full Text Available Drowning kills at least 372,000 people worldwide every year and is the 3rd leading cause of unintentional death, accounting for 7% of all deaths stemming from accidents (WHO, 2014. Conceptually, “drowning” is a complex and multi-faceted phenomenon, characterized as a chain of events (Bierens, 2006. Drowning is defined as the process of experiencing respiratory impairment from immersion or submersion in liquid. Research on drowning as a phenomenon presents several difficulties - most of all, that global data concerning the number of occurrences are not accurate. Nevertheless, detailed analysis of the registered incidents allows the identification of risk factors of drowning. An in-depth analysis of the risk factors is the basis for the creation of targeted and effective strategies to prevent drowning. Due to variability of situations which could lead to a drowning episode, experts suggest the adoption of a multi-layer prevention model, rather than opting for isolated measures, since no single measure can prevent all deaths and injuries caused by submersion. Among the preventive measures we would like to emphasize instruction in swimming and water safety. So, what does "knowing how to swim" really mean? Some authors define mastery of this competence as swimming a given distance, while others put the emphasis on how this/any given distance is swum (Stallman, Junge, & Blixt, 2008. It has long been realized that there is no contradiction between learning those competencies which make a person less susceptible to drowning and those competencies which prepare the path towards higher levels of performance and competition. Aquatic movement researchers and practitioners and drowning prevention researchers and practitioners, share in the responsibility for drowning prevention though they are often unaware of it. The question “What should be taught to children?” is too infrequently asked. There remains great variation in what is taught and programs

  3. Leading Your Leaders

    Science.gov (United States)

    Hale, Wayne N.

    2008-01-01

    life is good. More often when an unbelievably difficult test fails, we are left with a very long discussion of why and what was wrong in the design or execution of the test. Make sure that the test is well defined. Even then, it is important to explain to your leaders what inherent accuracy (or error) the test conditions or equipment have and what the assumptions or initial conditions were for the test. Test results without a good understanding of the test's accuracy or the pedigree of the test assumptions are worth very little. Finally, there is flight test data. Always limited, never at the edge of the envelope, it still shows how the real hardware works in a combined environment. Flight experience is dangerous because it typically doesn't show how close to the edge of the cliff the equipment is operating, but it does demonstrate how the hardware really works. A flight test is the ultimate test, again taken with the knowledge that it is probably not the extreme but something more like the middle of the environmental and systems performance. Good understanding of a problem and its solution always relies on a combination of all these methods. Be sure to lead your leaders by using all the tools you have at your disposal. At the end of the day, decisions in space flight always come down to a risk trade. Our business is not remotely safe, not in the sense that the public, the media, or our legislators use the term. Everything we do has a risk, cost, schedule, or performance trade-off. For your leaders to make an appropriate decision, you need to educate them, lead them, talk with them, and engage them in the discussion until full understanding takes place. It's your job. *

  4. The next-to-leading order (NLO) gluon distribution from DGLAP ...

    Indian Academy of Sciences (India)

    leading order (NLO) is obtained by applying the method of characteristics. Its compatibility with double leading logarithmic approximation (DLLA) asymptotics is discussed and comparison with the exact ones like GRV98NLO is made. The solution ...

  5. Manurial properties of lead nitrate

    Energy Technology Data Exchange (ETDEWEB)

    Berry, R A

    1924-01-01

    Water culture, pot and field experiments were conducted in order to determine the toxic and stimulating limit of lead nitrate in solution. Oats and rye grass were evaluated for evidence of lead poisoning. Results indicate that except in solutions of fairly high concentration, soil adsorbs the lead and destroys the toxicity of soluble lead salts. There was evidence to show that the addition of lead salts increased the rate of nitrification in soil.

  6. Basic principles of lead and lead-bismuth eutectic application in blanket of fusion reactors

    International Nuclear Information System (INIS)

    Beznosov, A.V.; Pinaev, S.S.; Muraviev, E.V.; Romanov, P.V.

    2005-01-01

    High magnetohydrodynamic pressure drop is an important issue for liquid metal blanket concepts. To decrease magnetohydrodynamic resistance authors propose to form insulating coatings on internal surface of blanket ducts at any moment of fusion reactor exploitation. It may be achieved easily if lead or lead-bismuth eutectic is used and technology of oxidative potential handling is applied. A number of experiments carried out in NNSTU show the availability of the proposed technology. It bases on formation of the insulating coatings that consist of the oxides of components of the structural materials and of the coolant components. In-situ value of the insulating coatings characteristics ρδ is ∼ 10 -5 Ohm·m 2 for steels and 5,0x10 -6 - 5,0x10 -5 Ohm·m 2 for vanadium alloys. Thermal cycling is possible during exploitation of a blanket. The experimental research of the insulating coatings properties during thermal cycling have shown that the coatings formed into the lead and lead-bismuth coolants save there insulating properties. Experience of many years is an undoubted advantage of the lead-bismuth coolant and less of the lead coolant in comparison with lithium. Russian Federation possesses of experience of exploitation of the research and industrial facilities, of experience of creation of the pumps, steamgenerators and equipment with heavy liquid metal coolants. The unique experience of designing, assembling and exploitation of the fission reactors with lead-bismuth coolant is also available. The problem of technology of lead and lead-bismuth coolants for power high temperature radioactive facilities has been solved. Accidents, emergency situations such as leakage of steamgenerators or depressurization of gas system in facilities with lead and lead-bismuth coolants have been explored and suppressed. (author)

  7. Lead in teeth from lead-dosed goats: Microdistribution and relationship to the cumulative lead dose

    International Nuclear Information System (INIS)

    Bellis, David J.; Hetter, Katherine M.; Jones, Joseph; Amarasiriwardena, Dula; Parsons, Patrick J.

    2008-01-01

    Teeth are commonly used as a biomarker of long-term lead exposure. There appear to be few data, however, on the content or distribution of lead in teeth where data on specific lead intake (dose) are also available. This study describes the analysis of a convenience sample of teeth from animals that were dosed with lead for other purposes, i.e., a proficiency testing program for blood lead. Lead concentration of whole teeth obtained from 23 animals, as determined by atomic absorption spectrometry, varied from 0.6 to 80 μg g -1 . Linear regression of whole tooth lead (μg g -1 ) on the cumulative lead dose received by the animal (g) yielded a slope of 1.2, with r 2 =0.647 (p -1 , were found in circumpulpal dentine. Linear regression of circumpulpal lead (μg g -1 ) on cumulative lead dose (g) yielded a slope of 23 with r 2 =0.961 (p=0.0001). The data indicated that whole tooth lead, and especially circumpulpal lead, of dosed goats increased linearly with cumulative lead exposure. These data suggest that circumpulpal dentine is a better biomarker of cumulative lead exposure than is whole tooth lead, at least for lead-dosed goats

  8. Lead pollution sources and Impacts

    International Nuclear Information System (INIS)

    El-Haggar, S.M.; Saad, S.G.; Saleh, S.K.; El-Kady, M.A.

    1996-01-01

    Despite the medical awareness of lead toxicity, and despite legislation designed to reduce environmental contamination, lead is one of the most widely used heavy metals. Significant human exposure occurs from automobile exhaust fumes, cigarette smoking, lead-based paints and plumbing systems lead spread in the environment can take place in several ways, the most important of which is through the lead compounds released in automobile exhaust as a direct result of the addition of tetraethyl or tetraethyl lead to gasoline as octane boosting agents. Of special is the effect of lead pollution on children, which affects their behavioral and educational attributes considerably. The major channel through through which lead is absorbed is through inhalation of lead compounds in the atmosphere. Lead is a heavy metal characterized its malleability, ductility and poor conduction of electricity. So, it has a wide range of applications ranging from battery manufacturing to glazing ceramics. It is rarely found free in nature but is present in several minerals and compounds. The aim of this paper is to discuss natural and anthropogenic sources of lead together with its distribution and trends with emphasis on egypt. The effects of lead pollution on human health, vegetation and welfare are also presented. It could be concluded that, the excessive release of lead into the environment, especially through the atmosphere, can produce many detrimental and sometimes fatal effects on human, agriculture and zoological life. Besides, it is very plain that there is a serious problem of pollution lead in egypt and specially in cairo. 7 figs

  9. Lead Contamination and Microbial Lead Tolerance in Soils at Major ...

    African Journals Online (AJOL)

    Devika

    ABSTRACT: Lead pollution and lead tolerance levels of microbes in soil at major road junctions in Benin. City were investigated. Results revealed that distance from the road junctions affected the concentrations of lead in soil, as well as the microbial population density and types of microbes present in the soil. The highest ...

  10. Lead Contamination and Microbial Lead Tolerance in Soils at Major ...

    African Journals Online (AJOL)

    Lead pollution and lead tolerance levels of microbes in soil at major road junctions in Benin City were investigated. Results revealed that distance from the road junctions affected the concentrations of lead in soil, as well as the microbial population density and types of microbes present in the soil. The highest concentrations ...

  11. Leaded gasoline - an environmental problem

    International Nuclear Information System (INIS)

    Petrushevska, Ljubica

    2001-01-01

    In the European countries it is a clear trend towards the increasing consumption of unleaded gasolines. Driving force of this trend is, on the one hand the high toxicity of lead compounds and on the other, the necessity of purification of exhaust gases by catalytic converters, for which the lead represent a catalyst poison. In Macedonia, the limit lead content in the leaded gasolines is relatively high (0,6 g/l), as well as the consumption of the leaded gasolines. Rapid and complete transition to unleaded gasolines can be realized by the concept of step by step reduction of lead in our gasolines. (Original)

  12. Experimental lead poisoning in chickens

    Energy Technology Data Exchange (ETDEWEB)

    Silven, L.

    1967-01-01

    Poisoning of water fowl due to the intake of lead shot is not rare in the USA. In order to study this kind of poisoning more closely domestic fowl were given varying amounts of lead shot and lead powder. This treatment did not provoke any symptoms of poisoning. Chemical analyses of different organs, muscles, skeleton and eggs yielded low lead values. It is concluded that the low toxicity of lead administered as lead shot to the domestic fowl is due to a low absorption rate from the gastro-intestinal tract.

  13. Decontamination and coating of lead

    International Nuclear Information System (INIS)

    Rankin, W.N.; Bush, S.P.; Lyon, C.E.; Walker, V.

    1988-01-01

    Technology is being developed to decontaminate lead used in shielding applications in contaminated environments for recycle as shieldings. Technology is also being developed to coat either decontaminated lead or new lead before it is used in contaminated environments. The surface of the coating is expected to be much easier to decontaminate than the original lead surface. If contamination becomes severely embedded in the coating and cannot be removed, it can be easily cut with a knife and removed from the lead. The used coating can be disposed of as radioactive (hot hazardous) waste. The lead can then be recoated for further use as a shielding material

  14. Clinical performance of different DF-4 implantable cardioverter defibrillator leads.

    Science.gov (United States)

    Sarrazin, Jean-François; Philippon, François; Sellier, Romain; André, Philippe; O'Hara, Gilles; Molin, Franck; Nault, Isabelle; Blier, Louis; Champagne, Jean

    2018-06-01

    Implantable cardioverter-defibrillator (ICD) DF-4 connectors have been introduced to facilitate defibrillator lead connection and to reduce the size of device header. There are limited data regarding the overall performance of those leads and no comparison between different ICD DF-4 leads. This is a cohort study of consecutive patients implanted with ICD DF-4 lead system at one University Centre between October 2010 and February 2015. A historical control group of patients with ICD DF-1 lead implantation was used for comparison. The following ICD DF-4 leads were evaluated: St. Jude Medical Durata 7122Q (St. Jude Medical, St. Paul, MN, USA), Medtronic Sprint Quattro Secure 6935 M (Medtronic Inc., Minneapolis, MN, USA), Boston Scientific Endotak Reliance 4-Site 0293 (Boston Scientific, Marlborough, MA, USA), and Boston Scientific Reliance 4-Front 0693. This study evaluated the acute and mid-term performances of those leads as well as complications. A total of 812 patients (age 63 ± 12 years, 80% male, left ventricular ejection fraction 31 ± 12%) underwent implantation of an ICD DF-4 lead. Acute and follow-up R-wave sensing and threshold were excellent. Compared to implantation, intrinsic R waves were higher at follow-up for Boston Scientific and Medtronic leads, and pacing lead impedances were lower for all leads at first follow-up (P < 0.001). The number of lead dislodgement or failure was similar between all leads. The estimated lead survival rates at 3 years were 95.6% for Boston Scientific Endotak 4-Site, 97.1% for Boston Scientific 4-Front, 97.7% for Medtronic Sprint Quattro, and 97.5% for St. Jude Durata (P  =  0.553). All ICD DF-4 leads had excellent acute and mid-term electrical performances. Longer follow-up will be necessary to confirm their sustained performance. © 2018 Wiley Periodicals, Inc.

  15. Spectrochemical determination of lead in wines

    Directory of Open Access Journals (Sweden)

    DRAGAN MARKOVIC

    2000-06-01

    Full Text Available The determination of lead in wines of different origin was performed by means of atomic emission spectroscopy with argon stabilized DC. U-shaped arc and electrothermal atomic absorption spectrometry. The comparison of the results obtained by the direct and standard addition method has indicated the presence of a depressive effect of the complex organic matrix. The effect is avoided successfully by mineralization, as well as by dissolution of the samples. Thus, a relative simple but precise and sensitive method involving the application of a stabilized arc and photoelectric detection with time integration of the emission signals is recommended for the determination of low concentrations of lead in wines. The complex organic matrix was investigated by recording the IR spectra of different wine fractions.

  16. Forming lead-based anodes

    Energy Technology Data Exchange (ETDEWEB)

    Ogorodnichuk, V I; Voitsekhovich, R I

    1972-01-01

    Lead-based anodes can be produced by forming a layer of lead dioxide by chemical treatment in a solution of sulfuric acid in potassium permanganate at 80 to 100/sup 0/. The solution is mixed by compressed air. (RWR)

  17. Correlation between some parameters of lead absorption and lead intoxication

    Science.gov (United States)

    Waldron, H. A.

    1971-01-01

    Waldron, H. A. (1971).Brit. J. industr. Med.,28, 195-199. Correlation between some parameters of lead absorption and lead intoxication. Use has been made of data collected over a number of years from workers exposed to a lead hazard in a motor-car factory. The correlations between various parameters of lead absorption and lead intoxication were computed, including blood and urine lead concentrations, urinary coproporphyrin, ALA and PBG concentrations, and haemoglobin concentration. In all, 15 correlation coefficients were calculated, of which only six showed a statistically significant result (i.e., Plead and urine lead (r = 0·38, Plead and coproporphyrin (r = 0·42, Plead and ALA (r = 0·43, Plead and PBG (r = 0·19, P<0·05). PMID:5572689

  18. Common ECG Lead Placement Errors. Part I: Limb Lead Reversals

    Directory of Open Access Journals (Sweden)

    Allison V. Rosen

    2015-10-01

    Full Text Available Background: Electrocardiography (ECG is a very useful diagnostic tool. However, errors in placement of ECG leads can create artifacts, mimic pathologies, and hinder proper ECG interpretation. It is important for members of the health care team to be able to recognize the common patterns resulting from lead placement errors. Methods: 12-lead ECGs were recorded in a single male healthy subject in his mid 20s. Six different limb lead reversals were compared to ECG recordings from correct lead placement. Results: Classic ECG patterns were observed when leads were reversed. Methods of discriminating these ECG patterns from true pathologic findings were described. Conclusion: Correct recording and interpretation of ECGs is key to providing optimal patient care. It is therefore crucial to be able to recognize common ECG patterns that are indicative of lead reversals.

  19. Lead user projects in practice

    DEFF Research Database (Denmark)

    Brem, Alexander; Gutstein, Adele

    2018-01-01

    Earlier research on the lead user method is focused on individual case studies and how the method was applied in a specific context. In this paper, we take a broader approach, analyzing a sample of 24 lead user projects, which included working with 188 lead users. These projects were analyzed...

  20. Lead poisoning in domestic ducks

    Energy Technology Data Exchange (ETDEWEB)

    Rac, R; Crisp, C S

    1954-05-01

    The death of wild ducks, due to the ingestion of lead shop, occurs frequently and is well documented. This paper discusses the death of domestic ducks due to the ingestion of lead. It describes the symptoms, and pathology of the lead poisoning of a clutch of 11 ducklings which were being raised on a farm in Australia. 3 references, 1 table.

  1. A study on lead equivalent

    International Nuclear Information System (INIS)

    Lin Guanxin

    1991-01-01

    A study on the rules in which the lead equivalent of lead glass changes with the energy of X rays or γ ray is described. The reason of this change is discussed and a new testing method of lead equivalent is suggested

  2. Lead- or Lead-bismuth-cooled fast reactors

    International Nuclear Information System (INIS)

    Bouchter, J.C.; Courouau, J.L.; Dufour, P.; Guidez, J.; Latge, C.; Martinelli, L.; Renault, C.; Rimpault, G.

    2014-01-01

    Lead-cooled fast reactors are one of the 6 concepts retained for the 4. generation of nuclear reactors. So far no lead-cooled reactors have existed in the world except lead-bismuth-cooled reactors in soviet submarines. Some problems linked to the use of the lead-bismuth eutectic appeared but were satisfactorily solved by a more rigorous monitoring of the chemistry of the lead-bismuth coolant. Lead presents various advantages as a coolant: no reactivity with water and the air,a high boiling temperature and low contamination when irradiated. The main asset of the lead-bismuth alloy is the drop of the fusion temperature from 327 C degrees to 125 C degrees. The main drawback of using lead (or lead-bismuth) is its high corrosiveness with metals like iron, chromium and nickel. The high corrosiveness of the coolant implies low flow velocities which means a bigger core and consequently a bigger reactor containment. Different research programs in the world (in Europe, Russia and the USA) are reviewed in the article but it appears that the development of this type of reactor requires technological breakthroughs concerning materials and the resistance to corrosion. Furthermore the concept of lead-cooled reactors seems to be associated to a range of low output power because of the compromise between the size of the reactor and its resistance to earthquakes. (A.C.)

  3. Electrical properties of a novel lead alkoxide precursor: Lead glycolate

    International Nuclear Information System (INIS)

    Tangboriboon, Nuchnapa; Pakdeewanishsukho, Kittikhun; Jamieson, Alexander; Sirivat, Anuvat; Wongkasemjit, Sujitra

    2006-01-01

    The reaction of lead acetate trihydrate Pb(CH 3 COO) 2 .3H 2 O and ethylene glycol, using triethylenetetramine (TETA) as a catalyst, provides in one step access to a polymer-like precursor of lead glycolate [-PbOCH 2 CH 2 O-]. On the basis of high-resolution mass spectroscopy, chemical analysis composition, FTIR, 13 C-solid state NMR and TGA, the lead glycolate precursor can be identified as a trimer structure. The FTIR spectrum demonstrates the characteristics of lead glycolate; the peaks at 1086 and 1042 cm -1 can be assigned to the C-O-Pb stretchings. The 13 C-solid state NMR spectrum gives notably only one peak at 68.639 ppm belonging to the ethylene glycol ligand. The phase transformations of lead glycolate and lead acetate trihydrate to lead oxide, their microstructures, and electrical properties were found to vary with increasing temperature. The lead glycolate precursor has superior electrical properties relative to those of lead acetate trihydrate, suggesting that the lead glycolate precursor can possibly be used as a starting material for producing electrical and semiconducting ceramics, viz. ferroelectric, anti-ferroelectric, and piezoelectric materials

  4. Current leads for superconducting magnets

    International Nuclear Information System (INIS)

    Ishibashi, Kenji

    1989-01-01

    Current leads for superconducting magnets have been studied since 1960's. The technology of current leads may seem to have been established both in theory and experiment before the middle of 1970's. Nevertheless, a wide variety of superconducting magnets have been introduced in the last 15 years, and the demands for special current leads have increased in accordance to the variety. A steady advance has been made in the design theory and fabrication of current leads. This paper describes the recent current lead technology regarding the design theory, safety in accidents, and high current capability. (author)

  5. Presence of lead in opium.

    Science.gov (United States)

    Aghaee-Afshar, Mahmoud; Khazaeli, Payam; Behnam, Behzad; Rezazadehkermani, Mohammad; Ashraf-Ganjooei, Narges

    2008-09-01

    Opium addiction is a common form of addiction in Middle East countries such as Iran. Recently several reports suggested some kinds of pathologic findings such as abdominal pain, nephropathy, and anemia in opium addict patients. Such pathologic findings suggest lead poisoning in the patients. In this study, the concentration of lead in 10 opium samples was evaluated. The mean concentration of lead in the opium samples was 1.88 ppm. This may explain some of the pathologic findings found in addict patients. The authors would suggest further investigations to evaluate the lead concentration in opium addicts' sera and also routine screening for lead poisoning in opium addict patients.

  6. Neurophysiological effects of lead exposure

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, I.; Wildt, K.; Gullberg, B.; Berlin, M.

    1983-10-01

    A series of neurophysiological variables was measured for men occupationally exposed to lead. The results were related to the degree of lead exposure and to the concentrations of lead and zinc protoporphyrin in blood. A small but significant correlation was observed between lead exposure and motor and sensory conduction velocities in the lower limbs, the conduction velocities of slow motor fibers in the upper limbs, and also sensory nerve action potentials. It is suggested that a neurophysiological examination should be considered in the surveillance of the health of lead workers.

  7. Decontaminating lead bricks and shielding

    International Nuclear Information System (INIS)

    Lussiez, G.

    1994-01-01

    Lead used for shielding is often surface contaminated with radioisotopes and is therefore a RCRA D008 mixed waste. The technology-based standard for treatment is macroencapsulation. However, decontaminating and recycling the clean lead is a more attractive solution. Los Alamos National Laboratory decontaminates material and equipment contaminated with radioisotopes. Decontaminating lead poses special problems because of the RCRA hazard classification and the size of the inventory, now about 50 tons and likely to grow substantially of planned decommissioning operations. Thus lead, in the form of bricks and other shield shapes, is surface contaminated with fission products. One of the best methods for contaminated lead is removing the superficial layer of contamination with an abrasive medium under pressure. For lead, a mixture of alumina with water and air at about 40 psig rapidly and effectively decontaminates the lead. The abrasive medium is sprayed onto the lead in a scaled-off area. The slurry of abrasive and particles of lead falls through a floor and is collected in a sump. A pump sends the slurry mixture back to the spray gun, creating a continuous process. The process generates small volumes of lead slurry that can be solidified and, because it passes the TCLP, is not a mixed waste. The decontaminated lead can be released for recycling

  8. Decontaminating lead bricks and shielding

    International Nuclear Information System (INIS)

    Lussiez, G.W.

    1993-01-01

    Lead used for shielding is often surface contaminated with radioisotopes and is therefore a RCRA D008 mixed waste. The technology-based standard for treatment is macroencapsulation. However, decontaminating and recycling the clean lead is a more attractive solution. Los Alamos National Laboratory decontaminates material and equipment contaminated with radioisotopes. Decontaminating lead poses special problems because of the RCRA hazard classification and the size of the inventory, now about 50 tons and likely to grow substantially because of planned decommissioning operations. This lead, in the form of bricks and other shield shapes, is surface contaminated with fission products. One of the best methods for decontaminating lead is removing the thin superficial layer of contamination with an abrasive medium trader pressure. For lead, a mixture of alumina with water and air at about 40 psig rapidly and effectively decontaminates the lead. The abrasive medium is sprayed onto the lead in a sealed-off area. The slurry of abrasive and particles of lead falls through a floor grating and is collected in a sump. A pump sends the slurry mixture back to the spray gun, creating a continuous process. The process generates small volumes of contaminated lead slurry that can be solidified and, because it passes the TCLP, is not a mixed waste. The decontaminated lead can be released for recycling

  9. Involving Lead Users in Innovation

    DEFF Research Database (Denmark)

    Brem, Alexander; Bilgram, Volker; Gutstein, Adele

    2018-01-01

    Research on the lead user method has been conducted for more than thirty years and has shown that the method is more likely to generate breakthrough innovation than traditional market research tools. Based on a systematic literature review, this paper shows a detailed view on the broad variety...... of research on lead user characteristics, lead user processes, lead user identification and application, and success factors. The main challenge of the lead user method as identified in literature is the resource issue regarding time, manpower, and costs. Also, internal acceptance and the processing...... of the method have been spotted in literature, as well as the intellectual property protection issue. From the starting point of the initial lead user method process introduced by Lüthje and Herstatt (2004), results are integrated into a revisited view on the lead user method process. In addition, concrete...

  10. Large-capacity current leads

    International Nuclear Information System (INIS)

    Ballarino, A.

    2008-01-01

    Feeding superconducting magnets with reliable low-loss devices is a key issue for any cryo-electrical system. Conventional or HTS current leads can be used, and cooling methods, materials, and geometries can be chosen to optimize the thermo-electrical performance of the system. The LHC magnets are powered via more than 3000 current leads transporting altogether about 3 MA of current. With thousands of leads, the LHC lead project represents today the largest project of its kind ever undertaken. Following a review of the LHC lead project, an overview of the choices that can be made for the optimization of large capacity current leads is presented. Examples are given of other leads for large scale magnet systems for which the use of HTS is being envisaged

  11. Blood lead and lead-210 origins in residents of Toulouse

    International Nuclear Information System (INIS)

    Servant, J.; Delapart, M.

    1981-01-01

    Blood lead and lead-210 analyses were performed on blood samples from non-smoking residents of Toulouse (city of 400,000 inhabitants). Simultaneous surface soil lead content determinations were carried out by the same procedure on rural zone samples of southwestern France. The observed isotopic ratios were compared in order to evaluate food chain contamination. For an average of 19.7 +- 5.8 μg 100 cc -1 of lead in blood, atmospheric contamination amounts to 20%, estimated as follows: 6% from direct inhalation and 14% from dry deposits on vegetation absorbed as food. The natural levels carried over by the food chain reach 14.9 μg 100 cc -1 and have a 210 Pb/Pb concentration ratio of 0.055 dpmμg -1 . These results lead to a maximum value of 15 μg 100 cc -1 for natural lead in human blood according to the ICRP model. (author)

  12. Lead isotope ratios in artists' lead white: a progress report

    Energy Technology Data Exchange (ETDEWEB)

    Keisch, B; Callahan, R C [Carnegie-Mellon Univ., Pittsburgh, Pa. (USA)

    1976-07-01

    The lead isotope ratios in over four hundred samples of lead white have been determined. The samples represent various geographical sources and dates from the thirteenth century to the present. A new method for organizing this large volume of data is described which helps with the visualization of temporal and geographic patterns. A number of interesting relationships between lead isotope ratio and date or source are shown to exist. Some examples of successful applications of this methodology are described.

  13. Lead isotope ratios in artists' lead white: a progress report

    International Nuclear Information System (INIS)

    Keisch, B.; Callahan, R.C.

    1976-01-01

    The lead isotope ratios in over four hundred samples of lead white have been determined. The samples represent various geographical sources and dates from the thirteenth century to the present. A new method for organizing this large volume of data is described which helps with the visualization of temporal and geographic patterns. A number of interesting relationships between lead isotope ratio and date or source are shown to exist. Some examples of successful applications of this methodology are described. (author)

  14. Phase-out of leaded gasoline: a prescription for Lebanon

    International Nuclear Information System (INIS)

    Hashisho, Z.; El-Fadel, M.; Ayoub, G.; Baaj, H.

    2000-01-01

    Full text.Lead is a toxic heavy metal. Nevertheless, it has been mined and used for more than 800 years. Among the different contemporary sources of lead pollution, emissions from the combustion of leaded gasoline is of particular concern, as it can constitutes more than 90 percent of total lead emissions into the atmosphere in congested urban areas. Concentrations of lead in air and blood are strongly correlated with gasoline lead content and traffic volume. As a result of the increasing awareness about the dangers of lead to human health and the measures to manage urban air pollution, the use of leaded gasoline has been decreasing worldwide. In Lebanon, in the absence of policies to reduce the use of lead in gasoline or to favor the use of unleaded gasoline, leaded gasoline is the predominant grade. The objective of this research work is to analyze the current status of gasoline, and to assess the feasibility and prospect of such action. For this purpose, background information are presented, data about gasoline usage and specifications have been collected, field measurements have been performed and a public survey has been conducted. The comparison of the expected cost savings from phasing out leaded gasoline with the potential costs indicates that such action is economically highly justified. If effective regulatory measures are undertaken, leaded gasoline can be phased-out immediately without a significant cost

  15. Superconducting magnets and leads thereto

    International Nuclear Information System (INIS)

    Biltcliffe, M.N.; Hanley, P.E.; McKinnon, J.B.; Wheatley, R.W.

    1975-01-01

    The magnet described comprises a cryostat containing a superconducting coil for the generation of a magnetic field, with a short-circuiting superconducting link connected across the coil, and electrical leads extending through the cryostat to the coil; these leads are provided with joints within the cryostat to enable them to be detached from the coil and removed from the cryostat without interrupting the current through the coil, thus reducing heat conduction to the cryostat through the leads. The joints are arranged so that the leads can be readily detached and re-attached to the coil from outside the cryostat. Gas-tight seals are provided where the leads pass through the outer wall of the cryostat, with caps that can be secured after removal of the leads. This kind of magnet can provide a stable magnetic field continuously over long periods, such as is required in nuclear magnetic resonance spectrometers. (U.K.)

  16. Taking the Lead : Gender, Social Context and Preference to Lead

    NARCIS (Netherlands)

    Hong, A.P.C.I.; Schaafsma, J.; van der Wijst, P.J.

    2014-01-01

    Previous research has demonstrated that women tend to emerge as leaders less often than men. In the present study, we examined to what extent women's and men's preference to lead is influenced by social context. It was hypothesized that women have a less strong preference to lead than men in a

  17. Archives of Atmospheric Lead Pollution

    Science.gov (United States)

    Weiss, Dominik; Shotyk, William; Kempf, Oliver

    Environmental archives such as peat bogs, sediments, corals, trees, polar ice, plant material from herbarium collections, and human tissue material have greatly helped to assess both ancient and recent atmospheric lead deposition and its sources on a regional and global scale. In Europe detectable atmospheric lead pollution began as early as 6000years ago due to enhanced soil dust and agricultural activities, as studies of peat bogs reveal. Increased lead emissions during ancient Greek and Roman times have been recorded and identified in many long-term archives such as lake sediments in Sweden, ice cores in Greenland, and peat bogs in Spain, Switzerland, the United Kingdom, and the Netherlands. For the period since the Industrial Revolution, other archives such as corals, trees, and herbarium collections provide similar chronologies of atmospheric lead pollution, with periods of enhanced lead deposition occurring at the turn of the century and since 1950. The main sources have been industry, including coal burning, ferrous and nonferrous smelting, and open waste incineration until c.1950 and leaded gasoline use since 1950. The greatest lead emissions to the atmosphere all over Europe occurred between 1950 and 1980 due to traffic exhaust. A marked drop in atmospheric lead fluxes found in most archives since the 1980s has been attributed to the phasing out of leaded gasoline. The isotope ratios of lead in the various archives show qualitatively similar temporal changes, for example, the immediate response to the introduction and phasing out of leaded gasoline. Isotope studies largely confirm source assessments based on lead emission inventories and allow the contributions of various anthropogenic sources to be calculated.

  18. Safe leads and lead changes in competitive team sports

    Science.gov (United States)

    Clauset, A.; Kogan, M.; Redner, S.

    2015-06-01

    We investigate the time evolution of lead changes within individual games of competitive team sports. Exploiting ideas from the theory of random walks, the number of lead changes within a single game follows a Gaussian distribution. We show that the probability that the last lead change and the time of the largest lead size are governed by the same arcsine law, a bimodal distribution that diverges at the start and at the end of the game. We also determine the probability that a given lead is "safe" as a function of its size L and game time t . Our predictions generally agree with comprehensive data on more than 1.25 million scoring events in roughly 40 000 games across four professional or semiprofessional team sports, and are more accurate than popular heuristics currently used in sports analytics.

  19. Lead user projects in practice

    DEFF Research Database (Denmark)

    Brem, Alexander; Gutstein, Adele

    2018-01-01

    Earlier research on the lead user method is focused on individual case studies and how the method was applied in a specific context. In this paper, we take a broader approach, analyzing a sample of 24 lead user projects, which included working with 188 lead users. These projects were analyzed....... Moreover, crowdsourcing contests and netnography proved to be of significant value for the need, trend, and lead user identification phases. This paper concludes by discussing theoretical and practical implications, the limitations of this study, and recommendations for future studies....

  20. Decontaminating lead bricks and shielding

    International Nuclear Information System (INIS)

    Lussiez, G.W.

    1993-01-01

    Lead used for shielding is often surface contaminated with radionuclides and is therefore a Resource Conservation and Recovery Act (RCRA) D008 mixed waste. The technology-based standard for treatment is macroencapsulation. However, decontaminating and recycling the clean lead is a more attractive solution. Los Alamos National Lab. decontaminates material and equipment contaminated with radioisotopes. Decontaminating lead poses special problems because of the RCRA hazard classification and the size of the inventory, now about 100 metric tons and likely to grow substantially because of planned decommissioning operations. This lead, in the form of bricks and other shield shapes, is surface contaminated with fission products. One of the best methods for decontaminating lead is removing the thin superficial layer of contamination with an abrasive medium under pressure. For lead, a mixture of alumina with water and air at about 280 kPa (40 psig) rapidly and effectively decontaminates the lead. The abrasive medium is sprayed onto the lead in a sealed-off area. The slurry of abrasive and particles of lead falls through a floor grating and is collected in a pump. A pump sends the slurry mixture back to the spray gun, creating a continuous process

  1. Neurological aspects of lead intoxication

    Energy Technology Data Exchange (ETDEWEB)

    Lehner, H

    1980-05-08

    This study gives a survey over the medical and scientific literature on lead intoxications, which were published until 1979. Neurologic aspects are of particular interest. At present dramatic cases of lead intoxications occur only rarely. However, there are numerous studies about cases of chronical, partly subclinical intoxications. This chronical type of lead intoxication can become manifest clinically as relatively vague symptoms, for example vertigos, insomnia, headaches and weakness. Contrary to this, serious encephalopathies, even with fatal outcome, and polyneuropathies with typical paresis of the radial nerve are preferably observed in acute lead intoxications. Besides the numerous sources of intoxication, also the different opinions found in literature are discussed, concerning the effects of lead on the human body. The fact that there are differing opinions about the limiting value of the blood-lead level at which intoxication symptoms have to be expected, becomes apparent when the determined blood-lead level values are compared and evaluated. Besides the description of general intoxication effects, the discussion of the neurologic aspects found in literature - not only those concerning the central, but also the peripheral system - are preferably concerned. Reports about neuropsychical alterations due to lead exposure, which are mainly found in children, supplement the numerous descriptions of the macroscopic and microscopic alterations of the nervous system provoked by lead. Finally the therapeutic and prophylactic measures given in the literature are discussed.

  2. Lead (Environmental Health Student Portal)

    Science.gov (United States)

    ... Air Pollution Home Indoor Air Pollution Outdoor Air Pollution Particulate Matter Ozone Chemicals Chemicals Home Mercury Lead Arsenic Volatile Organic Compounds Plastics Pesticides Climate Change ...

  3. Erythrocyte fluorescence and lead intoxication.

    Science.gov (United States)

    Clark, K G

    1976-01-01

    Blood samples from people exposed to inorganic lead were examined by fluorescence microscopy for excess erythrocyte porphyrin. With continued lead absorption, fluorescent erythrocytes appeared in the circulation of workers handling this metal or its compounds, and they progressively increased in number and brilliance. These changes ensued if the blood lead concentration was maintained above 2-42 mumol/l (50 mug/100 ml), and preceded any material fall in the haemoglobin value. At one factory, 62-5% of 81 symptomless workers showed erythrocyte fluorescence attributable to the toxic effects of lead. Excess fluorocytes were found in blood samples from a child with pica and three of her eight siblings. These four were subsequently shown to have slightly increased blood lead concentrations (2-03 to 2-32 mumol/l). Fluorescence microscopy for excess erythrocyte porphyrin is a sensitive method for the detection of chronic lead intoxication. A relatively slight increase in the blood lead is associated with demonstrabel changes in erythrocyte porphyrin content. The procedure requires little blood, and may be performed upon stored samples collected for lead estimation. The results are not readily influenced by contamination, and provide good confirmatory evidence for the absorption of biochemically active lead. PMID:963005

  4. Enhanced Leads and Appointment System

    Data.gov (United States)

    Social Security Administration — The data asset contains information on current or upcoming appointments, individuals who will be attending the appointment, potential intent to file a claim (lead),...

  5. Lead Poisoning in Wild Birds

    Science.gov (United States)

    Lahner, Lesanna L.; Franson, J. Christian

    2009-01-01

    Lead in its various forms has been used for thousands of years, originally in cooking utensils and glazes and more recently in many industrial and commercial applications. However, lead is a potent, potentially deadly toxin that damages many organs in the body and can affect all animals, including humans. By the mid 1990s, lead had been removed from many products in the United States, such as paint and fuel, but it is still commonly used in ammunition for hunting upland game birds, small mammals, and large game animals, as well as in fishing tackle. Wild birds, such as mourning doves, bald eagles, California condors, and loons, can die from the ingestion of one lead shot, bullet fragment, or sinker. According to a recent study on loon mortality, nearly half of adult loons found sick or dead during the breeding season in New England were diagnosed with confirmed or suspected lead poisoning from ingestion of lead fishing weights. Recent regulations in some states have restricted the use of lead ammunition on certain upland game hunting areas, as well as lead fishing tackle in areas frequented by common loons and trumpeter swans. A variety of alternatives to lead are available for use in hunting, shooting sports, and fishing activities.

  6. In vivo x-ray fluorescence of bone lead in the study of human lead metabolism: Serum lead, whole blood lead, bone lead, and cumulative exposure

    International Nuclear Information System (INIS)

    Cake, K.M.; Chettle, D.R.; Webber, C.E.; Gordon, C.L.

    1995-01-01

    Traditionally, clinical studies of lead's effect on health have relied on blood lead levels to indicate lead exposure. However, this is unsatisfactory because blood lead levels have a half-life of approximately 5 weeks, and thus reflect recent exposure. Over 90% of the lead body burden is in bone, and it is thought to have a long residence time, thus implying that measurements of bone lead reflect cumulative exposure. So, measurements of bone lead are useful in understanding the long-term health effects of lead. Ahlgren reported the first noninvasive measurements of bone lead in humans, where γ-rays from 57 Co were used to excite the K series x-rays of lead. The lead detection system at McMaster University uses a 109 Cd source which is positioned at the center of the detector face (HPGe) and a near backscatter (∼160 degrees) geometry. This arrangement allows great flexibility, since one can sample lead in a range of different bone sites due to a robust normalization technique which eliminates the need to correct for bone geometry, thickness of overlying tissue, and other related factors. The effective radiation dose to an adult during an x-ray fluorescence bone lead measurement is extremely low, being 35 nSv. This paper addresses the issue of how bone, whole blood, and serum lead concentrations can be related in order to understand a person's lead exposure history

  7. Theory of the Influence of Phonon-Phonon and Electron-Phonon Interactions on the Scattering of Neutrons by Crystals; Theorie de l'influence des interactions phonon-phonon et electron-phonon sur la diffusion des neutrons par des cristaux; Teoriya vliyaniya vzaimodejstvij fonon-fonon iehlvktron-fonon na rasseyanie nejtronov kristalla-; Teoria de la influencia de las interacciones fonon-fonon y electron-fonon en la dispersion de neutrones por cristales

    Energy Technology Data Exchange (ETDEWEB)

    Kokkedee, J J.J. [Institute for Theoretical Physics of the University of Utrecht (Netherlands)

    1963-01-15

    interatomic or interionic distance in the crystal). Approximate calculations are performed to give some insight into the orders of magnitude of the effects under study. (author) [French] Comme le predit la theorie harmonique, le spectre de la diffusion inelastique coherente de neutrons par un monocristal non conducteur, pour un angle de diffusion donne, se compose d'une serie de pics de fonction delta, qui se superposent a un bruit de fond continu. Les pics correspondent a des phenomenes a un phonon, dans lesquels un phonon est absorbe ou emis par le neutron; le bruit de fond provient de phenomenes a plusieurs phonons. Lorsqu'il existe des forces anharmoniques (interaction phonon-phonon) les pics de fonction delta s'elargissent pour former des pics finis et leur frequence centrale est dephasee par rapport aux valeurs harmoniques. Dans le cas d'un metal il y a, en plus des interactions phonon-phonon, une interaction entre les phonons et les electrons de conduction, laquelle contribue a dephaser et elargir encore davantage les pics a un phonon. Continuant les travaux de Van Hove (qui avait considere le cas relativement simple d'un cristal non conducteur a l'etat fondamental, soit T = 0{sup o}K) l'auteut a etudie les deplacements et les largeurs des pics de diffusion resultant des interactions indiquees plus haut, a l'aide de la theorie de la perturbation a plusieurs particules, en ayant largement recours a la methode des diagrammes. Il admet, avant tout examen du probleme, que quelle que soit la force des interactions, la largeur de chaque pic est petite par rapport a la valeur de la frequence en son centres dans ces conditions seulement, on peut considerer que les pics sont bien definis par rapport au bruit de fond, si les calculs d'interaction sont pousses jusqu'aux ordres superieurs. On estime que cette hipothbse est realisee tant que les temperatures ne sont pas trop elevees et que les valeurs du vecteur d'onde des phonons ne sont pas trop considerables. La methode

  8. Leading change: a concept analysis.

    Science.gov (United States)

    Nelson-Brantley, Heather V; Ford, Debra J

    2017-04-01

    To report an analysis of the concept of leading change. Nurses have been called to lead change to advance the health of individuals, populations, and systems. Conceptual clarity about leading change in the context of nursing and healthcare systems provides an empirical direction for future research and theory development that can advance the science of leadership studies in nursing. Concept analysis. CINAHL, PubMed, PsycINFO, Psychology and Behavioral Sciences Collection, Health Business Elite and Business Source Premier databases were searched using the terms: leading change, transformation, reform, leadership and change. Literature published in English from 2001 - 2015 in the fields of nursing, medicine, organizational studies, business, education, psychology or sociology were included. Walker and Avant's method was used to identify descriptions, antecedents, consequences and empirical referents of the concept. Model, related and contrary cases were developed. Five defining attributes of leading change were identified: (a) individual and collective leadership; (b) operational support; (c) fostering relationships; (d) organizational learning; and (e) balance. Antecedents were external or internal driving forces and organizational readiness. The consequences of leading change included improved organizational performance and outcomes and new organizational culture and values. A theoretical definition and conceptual model of leading change were developed. Future studies that use and test the model may contribute to the refinement of a middle-range theory to advance nursing leadership research and education. From this, empirically derived interventions that prepare and enable nurses to lead change to advance health may be realized. © 2016 John Wiley & Sons Ltd.

  9. Lead poisoning from souvenir earthenware.

    Science.gov (United States)

    Hellström-Lindberg, Eva; Björklund, Andreas; Karlson-Stiber, Christine; Harper, Pauline; Seldén, Anders I

    2006-02-01

    A case of massive lead poisoning from juice contained in a Greek earthenware jug as well as six satellite cases of high lead exposure of similar origin is reported. The intoxicated patient was successfully treated with dimercaptosuccinic acid. Ceramic producers should adhere to the longstanding European legislation.

  10. Lead-free primary explosives

    Science.gov (United States)

    Huynh, My Hang V.

    2010-06-22

    Lead-free primary explosives of the formula (cat).sub.Y[M.sup.II(T).sub.X(H.sub.2O).sub.6-X].sub.Z, where T is 5-nitrotetrazolate, and syntheses thereof are described. Substantially stoichiometric equivalents of the reactants lead to high yields of pure compositions thereby avoiding dangerous purification steps.

  11. Blood Test: Lead (For Parents)

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Blood Test: Lead KidsHealth / For Parents / Blood Test: Lead What's ... español Análisis de sangre: plomo What Is a Blood Test? A blood test is when a sample of ...

  12. Photocatalyzed removal of lead ion from lead-chelator solution

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Young Hyun; Na, Jung Won; Sung, Ki Woung [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1994-07-01

    The present study was undertaken to examine the influence of such chelating agents on the ease and speed of photocatalyzed metal removal and deposition. With excess EDTA, the free EDTA competes with Pb for oxidation, and at a ten fold excess, no lead oxidation (hence removal) occurs. With insufficient EDTA, the corresponding initial concentration of Pb-EDTA is decreased; after its destruction, the remaining Pb{sup 2+} is removed more slowly, at rates found with lead nitrate solution. The net result is that the maximum rate of lead deposition occurs at the stoichiometric ratio of 1:1 EDTA : Pb{sup 2+}.

  13. Distribution of lead in teeth

    Energy Technology Data Exchange (ETDEWEB)

    Fremlin, J H; Tanti-Wipawin, W [Birmingham Univ. (UK). Dept. of Physics

    1976-07-01

    There is currently much concern with the amount of lead in the environment. Measurement of lead in teeth is being used to give information on the integrated uptake of lead by the individual over a period. The distribution of lead within individual teeth, is examined with the object of distinguishing lead deposited during formation or calcification from that taken up by the tooth over its working life after eruption. A tooth is sectioned and bombarded with 30-MeV ions of helium-3 from the Birmingham 1.52-m cyclotron, which produces polonium isotopes. The main useful activity is due to polonium-206, an ..cap alpha.. emitter, half-life 8 d. These ..cap alpha.. particles can be recorded by a plastic solid-state track detector.

  14. Distribution of lead in teeth

    International Nuclear Information System (INIS)

    Fremlin, J.H.; Tanti-Wipawin, W.

    1976-01-01

    There is currently much concern with the amount of lead in the environment. Measurement of lead in teeth is being used to give information on the integrated uptake of lead by the individual over a period. The distribution of lead within individual teeth, is examined with the object of distinguishing lead deposited during formation or calcification from that taken up by the tooth over its working life after eruption. A tooth is sectioned and bombarded with 30-MeV ions of helium-3 from the Birmingham 1.52-m cyclotron, which produces polonium isotopes. The main useful activity is due to polonium-206, an α emitter, half-life 8 d. These α particles can be recorded by a plastic solid-state track detector. (U.K.)

  15. Next-To-Leading Order Determination of Fragmentation Functions

    CERN Document Server

    Bourhis, L; Guillet, J P; Werlen, M

    2001-01-01

    We analyse LEP and PETRA data on single inclusive charged hadron cross-sections to establish new sets of Next-to-Leading order Fragmentation Functions. Data on hadro-production of large-$p_{\\bot}$ hadrons are also used to constrain the gluon Fragmentation Function. We carry out a critical comparison with other NLO parametrizations.

  16. Determination of lead and cadmium in biological materials

    International Nuclear Information System (INIS)

    Stoeppler, M.; Backhaus, F.; Dahl, R.; Hagedorn-Goetz, H.; Hilpert, K.; Klahre, P.; Rutzel, H.; Valenta, P.; Nuernberg, H.W.; Dumont, M.

    1975-01-01

    Sampling techniques and experience, and decomposition methods are presented. The processes used in flameless atomic absorption spectrometry (including the method using automatic insertion of samples), pulse polarography and isotope dilution mass spectrometry are described. Finally, the results of lead and cadmium measurements in bovine liver, blood, urine and hair samples are reported and discussed with a comparison of methods in some cases

  17. Biosorption of lead phosphates by lead-tolerant bacteria as a mechanism for lead immobilization.

    Science.gov (United States)

    Rodríguez-Sánchez, Viridiana; Guzmán-Moreno, Jesús; Rodríguez-González, Vicente; Flores-de la Torre, Juan Armando; Ramírez-Santoyo, Rosa María; Vidales-Rodríguez, Luz Elena

    2017-08-01

    The study of metal-tolerant bacteria is important for bioremediation of contaminated environments and development of green technologies for material synthesis due to their potential to transform toxic metal ions into less toxic compounds by mechanisms such as reduction, oxidation and/or sequestration. In this study, we report the isolation of seven lead-tolerant bacteria from a metal-contaminated site at Zacatecas, México. The bacteria were identified as members of the Staphylococcus and Bacillus genera by microscopic, biochemical and 16S rDNA analyses. Minimal inhibitory concentration of these isolates was established between 4.5 and 7.0 mM of Pb(NO 3 ) 2 in solid and 1.0-4.0 mM of Pb(NO 3 ) 2 in liquid media. A quantitative analysis of the lead associated to bacterial biomass in growing cultures, revealed that the percentage of lead associated to biomass was between 1 and 37% in the PbT isolates. A mechanism of complexation/biosorption of lead ions as inorganic phosphates (lead hydroxyapatite and pyromorphite) in bacterial biomass, was determined by Fourier transform infrared spectroscopy and X-ray diffraction analyses. Thus, the ability of the lead-tolerant isolates to transform lead ions into stable and highly insoluble lead minerals make them potentially useful for immobilization of lead in mining waste.

  18. Environmental lead hazard to children.

    Science.gov (United States)

    Mittal, S K

    1992-01-01

    Clinically evident lead poisoning is rare in Indian children but is more common than in adults. In children, lead poisoning may appear as fever, seizures, anemia, or abdominal pain, while in adults it is more likely to manifest as chronic minor peripheral neuropathy or gum pigmentation. Children with acute lead poisoning can be treated with chelators such as EDTA and BAL, but many are left with permanent brain damage. The most common sources of acute lead poisoning in Indian children are inhalation of fumes from burned car batteries, ingestion of flaking paint, consuming food cooked in cheap aluminum or brass utensils, and eating contaminated soil. The sources of chronic lead poisoning are water from lead pipes and fumes from industrial or automotive exhaust. Another common source in India is application of "kajjal" to children's eyes. Sources of lead in Western countries, such as drinking water, canned food, residential paint, automotive fuel, and ambient air quality, are regulated by law. None of these are regulated in India.

  19. Lead neurotoxicity: In vitro and in vivo effects

    International Nuclear Information System (INIS)

    Rowles, T.K.

    1989-01-01

    Neuroglial cells, in particular astroglia, are thought to play a role in the neurotoxicity of lead. Two hypotheses have been proposed as possible cellular mechanism of this neurotoxicity: (1) lead affects intracellular levels of metals which mediate the toxic effects noted, and (2) lead affects intracellular heme biosynthesis which is then toxic to the cells. Zinc was found to have a profound effect on both intracellular lead levels and on cell numbers in lead-treated rat astroglia. A comparison of bovine and rat astroglia in culture indicated that the bovine cell cultures were not more sensitive to lead, even though calves are more sensitive. Lead was also shown to affect intracellular heme biosynthesis by a decrease in 14 C aminolevulinic acid incorporation into extractable heme in lead-treated rat astroglia. Finally, low levels of lead in immature guinea pigs caused changes in tissue levels of lead, iron, copper, and zinc with no change in weight gain or body:brain weight ratios

  20. Water quality criteria for lead

    Energy Technology Data Exchange (ETDEWEB)

    Nagpal, N.K.

    1987-01-01

    This report is one in a series that establishes water quality criteria for British Columbia. The report sets criteria for lead to protect a number of water uses, including drinking water, freshwater and marine aquatic life, wildlife, livestock, irrigation, and recreation. The criteria are set as either maximum concentrations of total lead that should not be exceeded at any time, or average concentrations that should not be exceeded over a 30-day period. Actual values are summarized.

  1. Chronic lead intoxication in calves

    Energy Technology Data Exchange (ETDEWEB)

    Wagenaar, G

    1963-01-01

    Four calves born in the winter of 1961-1962 died on a farm after a disease which had run its course for periods ranging from six weeks to a few months. A calf had also died showing similar symptoms during the previous year. All calves showed identical symptoms. Initially, their liveliness diminished; subsequently, they drank less and showed signs of pica. They finally died after the disease had run its course for about six weeks. The last calf, born late in February 1962, was in poor health as early as May, improved slightly when it had been sent out to grass but died in September, having fallen ill again in August. Autopsy was performed on three calves; all three were affected with chronic interstitial nephritis and uraemic endocarditis of the left auricle was present as well. The results obtained on toxicological investigation were indicative of lead poisoning. The liver of the calf was found to contain two mg of lead per kg, the cortex of the kidney containing twenty-five mg of lead per kg. These figures did not provide direct evidence of lead poisoning, but in evaluating these figures the fact was taken into account that the calf had no longer been able to ingest any lead for several months. Meanwhile, it was found that the stock-owner had fitted an old painted door in the calf-shed, which door was constantly being licked by the calves. The paint contained 18.6% of lead. This finding was followed by examination of the liver of a calf that had died previously. It was found to contain 49.7 mg of lead per kg. Accordingly, the calves had been affected with a form of lead poisoning running a relatively slow course, as a result of which the animals had developed chronic interstitial nephritis. The calves eventually died from uraemia. 4 references.

  2. Lead isotope in mineral exploration

    International Nuclear Information System (INIS)

    Gulson, B.L.

    1986-01-01

    This book provides an up-to-date state-of-the-art review of lead isotopes in mineral exploration. Beginning with an historical review on suggested uses of lead isotopes in mineral exploration, the author then outlines the theoretical aspects of lead isotopes and illustrates that the method is based on well-known principles of radioactive decay, from which isotopic signatures for different styles of mineralization are derived. The varying isotopic signatures are then introduced. The major part of the book details over 40 case histories for base and precious metals, uranium and tin using sampling media such as sulfides, gossans, soils, weathered bedrock, vegetation and groundwaters. Advantages and disadvantages of each are discussed. Examples are given of the use of lead isotopes in testing conceptual models for exploration. The success rate and cost-effectiveness of the method are illustrated by actual exploration examples. Analytical advances which should lower the cost of the method and future uses are outlined. Many of the case histories use recently published or unpublished data, 27 tables of which are given in an appendix. Details of sampling, the methods for obtaining the isotope ratios, and a commercially-available integrated lead isotope service are also provided. (Auth.)

  3. Lead poisoning after gunshot wound

    Directory of Open Access Journals (Sweden)

    Paulo Roberto de Madureira

    2000-05-01

    Full Text Available CONTEXT: Despite the absence of symptoms in the majority of patients carrying lead bullet fragments in their bodies, there needs to be an awareness of the possible signs and symptoms of lead intoxication when bullets are lodged in large joints like knees, hips and shoulders. Such patients merit closer follow-up, and even surgical procedure for removing the fragments. OBJECTIVE: To describe a patient who developed clinical lead intoxication several years after a gunshot wound. DESIGN: Case report. CASE REPORT: A single white 23-year-old male, regular job as a bricklayer, with a history of chronic alcohol abuse, showed up at the emergency department complaining of abdominal pain with colic, weakness, vomiting and diarrhea with black feces. All the symptoms had a duration of two to three weeks, and had been recurrent for the last two years, with calming during interval periods of two to three weeks. Abdominal radiograms showed a bullet lodged in the left hip, with a neat bursogram of the whole synovial capsule. A course of chelating treatment using calcium versenate (EDTACaNa2 intravenously was started. After the chelation therapy the patient had recurrence of his symptoms and a radical solution for the chronic mobilization of lead was considered. A hip arthroplasty procedure was performed, leading to complete substitution of the left hip.

  4. Lead and Hyperactivity: Lead Levels Among Hyperactive Children

    Science.gov (United States)

    David, Oliver J.; And Others

    1977-01-01

    In the study it is shown that within a group of 84 hyperactive children (4 to 11 years old) those for whom an organic etiology is present have lead burdens lower than in those for whom no apparent cause could be found. (Author/SBH)

  5. Local polar fluctuations in lead halide perovskites

    Science.gov (United States)

    Tan, Liang; Yaffe, Omer; Guo, Yinsheng; Brus, Louis; Rappe, Andrew; Egger, David; Kronik, Leeor

    The lead halide perovskites have recently attracted much attention because of their large and growing photovoltaic power conversion efficiencies. However, questions remain regarding the temporal and spatial correlations of the structural fluctuations, their atomistic nature, and how they affect electronic and photovoltaic properties. To address these questions, we have performed a combined ab initio molecular dynamics (MD) and density functional theory (DFT) study on CsPbBr3. We have observed prevalent anharmonic motion in our MD trajectories, with local polar fluctuations involving head-to-head motion of A-site Cs cations coupled with Br window opening. We calculate Raman spectra from the polarizability auto-correlation functions obtained from these trajectories and show that anharmonic A-site cation motion manifests as a broad central peak in the Raman spectrum, which increases in intensity with temperature. A comparison of the experimental Raman spectrum of hybrid organometallic MAPbBr3 and fully inorganic CsPbBr3 suggests that structural fluctuations in lead-halide perovskites is more general than rotation of polar organic cations and is intimately coupled to the inorganic framework.

  6. Microcirculation in experimental lead poisoning

    Energy Technology Data Exchange (ETDEWEB)

    Fimiani, R; Silvestroni, A; Iavicoli, N

    1973-01-01

    A study was made of the microvascular system of the auricle of the ear in 15 rabbits to which a 10 percent solution of lead acetate (0.5cm/sup 3//kg) was administered daily for 15 days through the gastric tract. Every 5 days up to the 35th day, determinations of blood and urine lead, free erythrocyte protoporphyrins and urinary coproporphyrins were carried out. Observations of the microvascular system were carried out in basic conditions after 6, 11, 16, 26 and 36 days. On the 6th day there was no pathological finding; on the 11th day small changes of the vascular content were observed, progressively assuming a sludge-like aspect. These findings confirm the hypothesis that the earliest changes caused by lead appear in the vascular content, before parietal changes occur.

  7. Jet calculus beyond leading logarithms

    International Nuclear Information System (INIS)

    Kalinowski, J.; Konishi, K.; Taylor, T.R.

    1981-01-01

    It is shown that the evolution of hadronic jets produced in hard processes can be studied in terms of a simple parton branching picture, beyond the leading log approximation of QCD. The jet calculus is generalized to any given order of logs (but always to all orders of αsub(s)). We discuss the general structure of the formalism. Universality of jet evolution is discussed. We consider also a jet calorimetry measure and the multiplicity distribution of final states in a form which allows a systematic improvement of approximation. To the next-to-leading order, we prove the finiteness and elucidate the scheme dependence of parton subprocess probabilities. The physical inclusive cross section is shown to be scheme independent: next-to-leading results for e + e - → q (nonsinglet) + X agree with those of Curci and others. (orig.)

  8. Initial occupational exposure to lead

    Energy Technology Data Exchange (ETDEWEB)

    Forni, A.; Cambiaghi, G.; Secchi, G.C.

    1976-01-01

    Serial chromosome and biochemical studies were carried out in 11 subjects before and during initial occupational exposure to moderate quantities of lead fumes in a storage battery plant. The rate of abnormal metaphases, mostly with chromatid and one-break chromosome aberrations, was approximately doubled after one month of work; it further increased after two months of work; remained in this range up to seven months of exposure; and then tended to decrease somewhat. Blood lead levels increased progressively in the first few months, then reached a steady state. Urinary lead and coproporphyrin levels increased sharply after one month of work, while urinary delta-aminolevulinic acid (ALA) levels increased moderately. The ALA dehydratase (ALAD) activity of red blood cells (RBCs) was reduced to almost 50 percent of the initial values after one month, decreased further in subsequent months, and remained decreased through the remainder of the study.

  9. Deformation properties of lead isotopes

    International Nuclear Information System (INIS)

    Tolokonnikov, S. V.; Borzov, I. N.; Lutostansky, Yu. S.; Saperstein, E. E.

    2016-01-01

    The deformation properties of a long lead isotopic chain up to the neutron drip line are analyzed on the basis of the energy density functional (EDF) in the FaNDF 0 Fayans form. The question of whether the ground state of neutron-deficient lead isotopes can have a stable deformation is studied in detail. The prediction of this deformation is contained in the results obtained on the basis of the HFB-17 and HFB-27 Skyrme EDF versions and reported on Internet. The present analysis reveals that this is at odds with experimental data on charge radii and magnetic moments of odd lead isotopes. The Fayans EDF version predicts a spherical ground state for all light lead isotopes, but some of them (for example, 180 Pb and 184 Pb) prove to be very soft—that is, close to the point of a phase transition to a deformed state. Also, the results obtained in our present study are compared with the predictions of some other Skyrme EDF versions, including SKM*, SLy4, SLy6, and UNE1. By and large, their predictions are closer to the results arising upon the application of the Fayans functional. For example, the SLy4 functional predicts, in just the same way as the FaNDF 0 functional, a spherical shape for all nuclei of this region. The remaining three Skyrme EDF versions lead to a deformation of some light lead isotopes, but their number is substantially smaller than that in the case of the HFB-17 and HFB-27 functionals. Moreover, the respective deformation energy is substantially lower, which gives grounds to hope for the restoration of a spherical shape upon going beyond the mean-field approximation, which we use here. Also, the deformation properties of neutron-rich lead isotopes are studied up to the neutron drip line. Here, the results obtained with the FaNDF 0 functional are compared with the predictions of the HFB-17, HFB-27, SKM*, and SLy4 Skyrme EDF versions. All of the EDF versions considered here predict the existence of a region where neutron-rich lead isotopes undergo

  10. Mortality study of lead workers

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, W C; Gaffey, W R

    1975-01-01

    The mortality of 7,032 men employed for one or more years in lead production facilities or battery plants was followed over a 23-year period, 1947-70. Lead absorption in many of these men was greatly in excess of currently accepted standards based upon urinary and blood lead concentrations available for a portion of the group. There were 1,356 deaths reported. The standardized mortality ratio (SMR) for all causes was 107 for smelter workers and 99 for battery plant workers. Death from neoplasms were in slight excess in smelters, but not significantly increased in battery plants. There were no excess deaths from kidney tumors. The SMR for cardiovascular-renal disease was 96 for smelter workers and 101 for battery plant workers. There was definitely no excess in deaths from either stroke or hypertensive heart disease; however, deaths classified as other hypertensive disease and unspecified nephritis or renal sclerosis were higher than expected. The life expectancy of lead workers was calculated to be approximately the same as that of all U.S. males.

  11. High temperature superconductor current leads

    International Nuclear Information System (INIS)

    Zeimetz, B.; Liu, H.K.; Dou, S.X.

    1996-01-01

    Full text: The use of superconductors in high electrical current applications (magnets, transformers, generators etc.) usually requires cooling with liquid Helium, which is very expensive. The superconductor itself produces no heat, and the design of Helium dewars is very advanced. Therefore most of the heat loss, i.e. Helium consumption, comes from the current lead which connects the superconductor with its power source at room temperature. The current lead usually consists of a pair of thick copper wires. The discovery of the High Temperature Superconductors makes it possible to replace a part of the copper with superconducting material. This drastically reduces the heat losses because a) the superconductor generates no resistive heat and b) it is a very poor thermal conductor compared with the copper. In this work silver-sheathed superconducting tapes are used as current lead components. The work comprises both the production of the tapes and the overall design of the leads, in order to a) maximize the current capacity ('critical current') of the superconductor, b) minimize the thermal conductivity of the silver clad, and c) optimize the cooling conditions

  12. Lead apron: room for improvement

    Energy Technology Data Exchange (ETDEWEB)

    Boothroyd, A.E.; Russell, J.G.B.

    1987-02-01

    The amount of red bone marrow not protected by a lead apron was used as an assessment of protection efficiency, and the effect of change of shape was calculated. It was concluded that change of shape would increase protection and cut down cost. (U.K.).

  13. OPAL Various Lead Glass Blocks

    CERN Multimedia

    These lead glass blocks were part of a CERN detector called OPAL (one of the four experiments at the LEP particle detector). OPAL uses some 12 000 blocks of glass like this to measure particle energies in the electromagnetic calorimeter. This detector measured the energy deposited when electrons and photons were slowed down and stopped.

  14. Copper, lead and zinc production

    International Nuclear Information System (INIS)

    Ayers, J.; Ternan, S.

    2001-01-01

    This chapter provides information on the by-products and residues generated during the production of copper, lead and zinc. The purpose of this chapter is to describe by-products and residues which are generated, how these may be avoided or minimised, and available options for the utilization and management of residues. (author)

  15. Current Leads, Links and Buses

    CERN Document Server

    Ballarino, A

    2014-01-01

    Electrical transfer from a room temperature power source to a superconducting system is done via conventional or superconducting current leads and superconducting buses or links. The principles of optimization of these devices are presented, with emphasis on the cryogenic, electrical, and superconductor related aspects that drive choices for a system.

  16. Triplet states in lead isotopes

    International Nuclear Information System (INIS)

    Naz, Tabassum; Ahmad, Shakeb; Abusara, H.

    2017-01-01

    Axial and triaxial calculations within RHB have been done to study the shape coexistence phenomena in the lead isotopes. Triplet states have been found in the 184-190 Pb which are in accordance with the experimental and other theoretical observations. The energy difference (in MeV) between the first two excited states also gives the evidence for the same

  17. Implementation Guide: Leading School Change

    Science.gov (United States)

    Whitaker, Todd

    2010-01-01

    This two-part "Implementation Guide" will help to deepen your understanding and sharpen your ability to implement each of the strategies discussed in "Leading School Change: Nine Strategies to Bring Everybody on Board" (ED509821). Part One offers discussion questions and activities which focus on each of the nine strategies. They can be completed…

  18. Lead in calcium supplements (abstract)

    International Nuclear Information System (INIS)

    Rehman, S.; Khalid, N.

    2011-01-01

    Lead present in calcium supplements is of grave concern as some lead levels have been measured up to the extent of regulatory limit set by the United States. Calcium supplements inevitably get contaminated with lead as both are naturally occurring elements. Therefore, it is imperative to indicate its level in these supplements in order to create awareness among consumers. In this study, a sophisticated analytical technique, atomic absorption spectrometry was used to analyze Pb contents in 27 commonly consumed Ca supplements manufactured by different national and multinational companies. The daily intake of lead through these supplements was calculated. Only 10% of the calcium supplements analyzed met the criteria of acceptable Pb levels (1.5 mu g/daily dose) in supplements/consumer products set by the United States. It was also found that Pb intake was highest in chelated calcium supplements 28.5 mu g/daily dose, whereas lowest 0.47 mu g/daily dose through calcium supplements with vitamin D formulation. In order to validate our results from the study conducted, IAEA-certified reference material (animal bone, H-5) was analyzed for its Pb levels. The levels of Pb determined were quite in good agreement with the certified values. (author)

  19. How to lead complex situations

    DEFF Research Database (Denmark)

    Hansen, Michael Pingel

    2013-01-01

    The military leader is experiencing increasingly more complex situations, whether it is as leader in a foreign combat environment or in the home-based public administration. Complex situations like these call for a special set of managerial responses and a special way of leading organisations...

  20. Current Leads, Links and Buses

    Energy Technology Data Exchange (ETDEWEB)

    Ballarino, A [European Organization for Nuclear Research, Geneva (Switzerland)

    2014-07-01

    Electrical transfer from a room temperature power source to a superconducting system is done via conventional or superconducting current leads and superconducting buses or links. The principles of optimization of these devices are presented, with emphasis on the cryogenic, electrical, and superconductor related aspects that drive choices for a system.

  1. Leading in a Technological Age

    Science.gov (United States)

    Yadgir, Sheri A.

    2011-01-01

    Technology is advancing more rapidly than at any time in history since the beginning of the Industrial Revolution. In fact, experts say that the world is leaving the Industrial Age of the 20th century and entering an Information Age that will lead into the future. These advances mean that important changes are being made in all areas of life--and…

  2. Gammatography of thick lead vessels

    International Nuclear Information System (INIS)

    Raghunath, V.M.; Bhatnagar, P.K.; Sundaram, V.M.

    1979-01-01

    Radiography, scintillation and GM counting and dose measurements using ionisation chamber equipment are commonly used for detecting flaws/voids in materials. The first method is mostly used for steel vessels and to a lesser extent thin lead vessels also and is essentially qualitative. Dose measuring techniques are used for very thick and large lead vessels for which high strength radioactive sources are required, with its inherent handling problems. For vessels of intermediate thicknesses, it is ideal to use a small strength source and a GM or scintillation counter assembly. At the Reactor Research Centre, Kalpakkam, such a system was used for checking three lead vessels of thicknesses varying from 38mm to 65mm. The tolerances specified were +- 4% variation in lead thickness. The measurements also revealed the non concentricity of one vessel which had a thickness varying from 38mm to 44mm. The second vessel was patently non-concentric and the dimensional variation was truly reproduced in the measurements. A third vessel was fabricated with careful control of dimensions and the measurements exhibited good concentricity. Small deviations were observed, attributable to imperfect bondings between steel and lead. This technique has the following advantages: (a) weaker sources used result in less handling problems reducing the personnel exposures considerably; (b) the sensitivity of the instrument is quite good because of better statistics; (c) the time required for scanning a small vessel is more, but a judicious use of a scintillometer for initial fast scan will help in reducing the total scanning time; (d) this method can take advantage of the dimensional variations themselves to get the calibration and to estimate the deviations from specified tolerances. (auth.)

  3. Deaths: Leading Causes for 2011.

    Science.gov (United States)

    Heron, Melonie

    2015-07-27

    This report presents final 2011 data on the 10 leading causes of death in the United States by age, sex, race, and Hispanic origin. Leading causes of infant, neonatal, and postneonatal death are also presented. This report supplements ‘‘Deaths: Final Data for 2011,’’ the National Center for Health Statistics’ annual report of final mortality statistics. Data in this report are based on information from all death certificates filed in the 50 states and the District of Columbia in 2011. Causes of death classified by the International Classification of Diseases, 10th Revision (ICD–10) are ranked according to the number of deaths assigned to rankable causes. Cause-of-death statistics are based on the underlying cause of death. In 2011, the 10 leading causes of death were, in rank order: Diseases of heart; Malignant neoplasms; Chronic lower respiratory diseases; Cerebrovascular diseases; Accidents (unintentional injuries); Alzheimer’s disease; Diabetes mellitus; Influenza and pneumonia; Nephritis, nephrotic syndrome and nephrosis; and Intentional self-harm (suicide). They accounted for 74% of all deaths occurring in the United States. Differences in the rankings are evident by age, sex, race, and Hispanic origin. Leading causes of infant death for 2011 were, in rank order: Congenital malformations, deformations and chromosomal abnormalities; Disorders related to short gestation and low birth weight, not elsewhere classified; Sudden infant death syndrome; Newborn affected by maternal complications of pregnancy; Accidents (unintentional injuries); Newborn affected by complications of placenta, cord and membranes; Bacterial sepsis of newborn; Respiratory distress of newborn; Diseases of the circulatory system; and Neonatal hemorrhage. Important variations in the leading causes of infant death are noted for the neonatal and postneonatal periods. All material appearing in this report is in the public domain and may be reproduced or copied without permission

  4. Deaths: Leading Causes for 2015.

    Science.gov (United States)

    Heron, Melonie

    2017-11-01

    Objectives-This report presents final 2015 data on the 10 leading causes of death in the United States by age, sex, race, and Hispanic origin. Leading causes of infant, neonatal, and postneonatal death are also presented. This report supplements "Deaths: Final Data for 2015," the National Center for Health Statistics' annual report of final mortality statistics. Methods-Data in this report are based on information from all death certificates filed in the 50 states and the District of Columbia in 2015. Causes of death classified by the International Classification of Diseases, Tenth Revision (ICD-10) are ranked according to the number of deaths assigned to rankable causes. Cause-of-death statistics are based on the underlying cause of death. Results-In 2015, the 10 leading causes of death were, in rank order: Diseases of heart; Malignant neoplasms; Chronic lower respiratory diseases; Accidents (unintentional injuries); Cerebrovascular diseases; Alzheimer's disease; Diabetes mellitus; Influenza and pneumonia; Nephritis, nephrotic syndrome and nephrosis; and Intentional self-harm (suicide). They accounted for 74% of all deaths occurring in the United States. Differences in the rankings are evident by age, sex, race, and Hispanic origin. Leading causes of infant death for 2015 were, in rank order: Congenital malformations, deformations and chromosomal abnormalities; Disorders related to short gestation and low birth weight, not elsewhere classified; Sudden infant death syndrome; Newborn affected by maternal complications of pregnancy; Accidents (unintentional injuries); Newborn affected by complications of placenta, cord and membranes; Bacterial sepsis of newborn; Respiratory distress of newborn; Diseases of the circulatory system; and Neonatal hemorrhage. Important variations in the leading causes of infant death are noted for the neonatal and postneonatal periods. All material appearing in this report is in the public domain and may be reproduced or copied without

  5. Deaths: leading causes for 2010.

    Science.gov (United States)

    Heron, Melonie

    2013-12-20

    This report presents final 2010 data on the 10 leading causes of death in the United States by age, sex, race, and Hispanic origin. Leading causes of infant, neonatal, and postneonatal death are also presented. This report supplements the Division of Vital Statistics' annual report of final mortality statistics. Data in this report are based on information from all death certificates filed in the 50 states and the District of Columbia in 2010. Causes of death classified by the International Classification of Diseases, Tenth Revision (ICD-10) are ranked according to the number of deaths assigned to rankable causes. Cause-of-death statistics are based on the underlying cause of death. In 2010, the 10 leading causes of death were, in rank order: Diseases of heart; Malignant neoplasms; Chronic lower respiratory diseases; Cerebrovascular diseases; Accidents (unintentional injuries); Alzheimer's disease; Diabetes mellitus; Nephritis, nephrotic syndrome and nephrosis; Influenza and pneumonia; and Intentional self-harm (suicide). These 10 causes accounted for 75% of all deaths occurring in the United States. Differences in the rankings are evident by age, sex, race, and Hispanic origin. Leading causes of infant death for 2010 were, in rank order: Congenital malformations, deformations and chromosomal abnormalities; Disorders related to short gestation and low birth weight, not elsewhere classified; Sudden infant death syndrome; Newborn affected by maternal complications of pregnancy; Accidents (unintentional injuries); Newborn affected by complications of placenta, cord and membranes; Bacterial sepsis of newborn; Respiratory distress of newborn; Diseases of the circulatory system; and Necrotizing enterocolitis of newborn. Important variations in the leading causes of infant death are noted for the neonatal and post-neonatal periods. All material appearing in this report is in the public domain and may be reproduced or copied without permission; citation as to source

  6. Deaths: Leading Causes for 2013.

    Science.gov (United States)

    Heron, Melonie

    2016-02-16

    This report presents final 2013 data on the 10 leading causes of death in the United States by age, sex, race, and Hispanic origin. Leading causes of infant, neonatal, and postneonatal death are also presented. This report supplements "Deaths: Final Data for 2013," the National Center for Health Statistics’ annual report of final mortality statistics. Data in this report are based on information from all death certificates filed in the 50 states and the District of Columbia in 2013. Causes of death classified by the International Classification of Diseases, Tenth Revision (ICD–10) are ranked according to the number of deaths assigned to rankable causes. Cause-of-death statistics are based on the underlying cause of death. In 2013, the 10 leading causes of death were, in rank order: Diseases of heart; Malignant neoplasms; Chronic lower respiratory diseases; Accidents (unintentional injuries); Cerebrovascular diseases; Alzheimer’s disease; Diabetes mellitus; Influenza and pneumonia; Nephritis, nephrotic syndrome and nephrosis; and Intentional self-harm (suicide). They accounted for 74% of all deaths occurring in the United States. Differences in the rankings are evident by age, sex, race, and Hispanic origin. Leading causes of infant death for 2013 were, in rank order: Congenital malformations, deformations and chromosomal abnormalities; Disorders related to short gestation and low birth weight, not elsewhere classified; Newborn affected by maternal complications of pregnancy; Sudden infant death syndrome; Accidents (unintentional injuries); Newborn affected by complications of placenta, cord and membranes; Bacterial sepsis of newborn; Respiratory distress of newborn; Diseases of the circulatory system; and Neonatal hemorrhage. Important variations in the leading causes of infant death are noted for the neonatal and postneonatal periods. All material appearing in this report is in the public domain and may be reproduced or copied without permission; citation as

  7. Deaths: Leading Causes for 2012.

    Science.gov (United States)

    Heron, Melonie

    2015-08-31

    This report presents final 2012 data on the 10 leading causes of death in the United States by age, sex, race, and Hispanic origin. Leading causes of infant, neonatal, and postneonatal death are also presented. This report supplements "Deaths: Final Data for 2012," the National Center for Health Statistics' annual report of final mortality statistics. Data in this report are based on information from all death certificates filed in the 50 states and the District of Columbia in 2012. Causes of death classified by the International Classification of Diseases, Tenth Revision (ICD-10) are ranked according to the number of deaths assigned to rankable causes. Cause-of-death statistics are based on the underlying cause of death. In 2012, the 10 leading causes of death were, in rank order: Diseases of heart; Malignant neoplasms; Chronic lower respiratory diseases; Cerebrovascular diseases; Accidents (unintentional injuries); Alzheimer's disease; Diabetes mellitus; Influenza and pneumonia; Nephritis, nephrotic syndrome and nephrosis; and Intentional self-harm (suicide). These causes accounted for 74% of all deaths occurring in the United States. Differences in the rankings are evident by age, sex, race, and Hispanic origin. Leading causes of infant death for 2012 were, in rank order: Congenital malformations, deformations and chromosomal abnormalities; Disorders related to short gestation and low birth weight, not elsewhere classified; Sudden infant death syndrome; Newborn affected by maternal complications of pregnancy; Accidents (unintentional injuries); Newborn affected by complications of placenta, cord and membranes; Bacterial sepsis of newborn; Respiratory distress of newborn; Diseases of the circulatory system; and Neonatal hemorrhage. Important variations in the leading causes of infant death are noted for the neonatal and postneonatal periods.

  8. Effect of lead acetate on learning and memory in rats

    Energy Technology Data Exchange (ETDEWEB)

    Seki, H; Maeda, H; Ohi, G; Yagyu, H

    1974-01-01

    To study the mental effects of exposure to lead, especially in auto exhaust in the ambient air, adult female Wistar rats were orally dosed with lead acetate at 125 mg(Pb)/30 g food for 6 weeks from the 3rd day of pregnancy to the 3rd week after delivery. Nine week-old male rats were examined as to learning and memory ability using a labyrinth in comparison to the ability of control rats. No significant deterioration of these abilities which might have been caused by exposure to lead in the rats early life stage was noted, although the mothers were given the maximal dose of lead they and the fetuses could tolerate.

  9. Lead evaluation in blood of workers of batteries industries

    International Nuclear Information System (INIS)

    Valbuena P, John J; Duarte, Martha; Marciales Clara

    2001-01-01

    In order to evaluate the occupational risk of exposure to lead of employees working in three small industries that recycle and manufacture acid lead batteries, the lead and zinc protoporphyrine (ZPP) blood content was determined. The determination was also performed on people not exposed in order to establish comparison values. Venous blood was collected in metal free heparinized glass tubes. Lead was analyzed by atomic absorption with graphite furnace and ZPP by fluorescence. According to Colombian legislation, it was found that around 31 % workers in this type of industries are in dangerous and intoxication exposure. It was also found that 91 % of workers exceed the level of 30 mg Pb/dL blood established as standard by the American Conference governmental Industrial Hygienists (ACGIH)

  10. Lead and Drinking Water from Private Wells

    Science.gov (United States)

    ... type=”submit” value=”Submit” /> Healthy Water Home Lead and Drinking Water from Private Wells Recommend on ... remove lead from my drinking water? What is lead? Lead is a naturally occurring bluish-gray metal ...

  11. Association of Lead Exposure, Serum Uric Acid and Parameters of Renal Function in Nigerian Lead-Exposed Workers

    Directory of Open Access Journals (Sweden)

    DD Alasia

    2010-09-01

    Full Text Available Background: The presence of hyperuricemia and renal function impairment, especially in the absence of urate stone formation is strongly suggestive of lead nephropathy. The evaluation of this association is essential in areas where lead exposure is still prevalent and uncontrolled. Objective: To determine the relationship between serum uric acid and renal function indices in lead-exposed workers. Methods: A cross-sectional study of 190 adults with occupational lead exposure and 80 adults (comparison group, matched for age and sex was performed in Port Harcourt, South-south Nigeria. Blood lead was used as the biomarker of lead exposure while serum urea, serum creatinine, urine albumin (using urine albumin:creatinine ratio, estimated glomerular filtration rate (GFR and serum uric acid were the renal function indices measured. Results: Occupationally lead-exposed subjects had a significantly (p = 0.008 higher mean±SD blood lead levels (50.37±24.58 μg/dL than the comparison group (41.40±26.85. The mean±SD serum urea (8.6±2.3 mg/dL, creatinine (1.0±0.2 mg/dL and serum uric acid (4.6±1.2 mg/dL were significantly (p < 0.01 higher in the study subjects than the comparison group (7.6±2.4, 0.9±0.2, and 3.9±1.1 mg/dL, respectively. The mean±SD creatinine clearance was significantly (p = 0.002 lower in the study subjects than the comparison group (98.9±21.3 vs. 108.2±25.2 mL/min/1.72 m2. Serum uric acid level correlated positively with serum creatinine (r = 0.134 and negatively with GFR (r = ‑0.151. Conclusion: People with occupational lead exposure are at risk of developing hyperuricemia and renal impairment.

  12. Community blood lead survey with emphasis on preschool children following lead dust pollution in Esperance, Western Australia.

    Science.gov (United States)

    Rossi, Enrico; McLaughlin, Virginia; Joseph, John; Bulsara, Max; Coleman, Kerryn; Douglas, Charles; Robertson, Andrew

    2012-04-01

    To assess the impact of airborne lead dust on blood lead levels in residents of Esperance, a regional Western Australian town, with particular reference to preschool children. Following identification of significant airborne lead contamination, residents were notified that a blood lead clinic was available to all, with testing of preschool children encouraged. About 40% (333 children) of the preschool group and about 20% of the remaining population were tested. The main measures were blood lead levels, prevalence of elevated results and comparisons to other Western Australian surveys. In preschoolers, 2.1% (seven children) had blood lead levels exceeding the current 10 μg/dL level of concern. This was not significantly different to two previous community-based surveys elsewhere in Western Australia. However, at a lower cut-off of 5 μg/dL, the prevalence of elevated lead levels was 24.6%, significantly higher than children tested in a previous Western Australian survey. The prevalence of blood lead levels of 10 μg/dL or greater in adults was 1.3% (26 adults), not significantly different from a previous Western Australian survey. The prevalence of preschool children with blood lead levels exceeding the current level of concern was not significantly increased. However, the increased prevalence of children with lead levels at or above 5 μg/dL demonstrates exposure to lead dust pollution. This episode of lead dust contamination highlights the need for strict adherence to environmental controls and effective monitoring processes to ensure the prevention of future events. © 2012 The Authors. ANZJPH © 2012 Public Health Association of Australia.

  13. Relational Leading and Dialogic Process

    DEFF Research Database (Denmark)

    Hansen, Lone Hersted

    The Ph.D. thesis contributes to a relational orientation to leading, emphasizing leadership as a shared, collaborative and co-creative activity. In this paradigm major emphasis is put on dialogue and interaction. Inspired by social constructionist ideas, the thesis considers approaches to learning...... and knowledge building as related to relational leading. The practices developed in the thesis research demonstrate that it is possible to create organizational learning and development through collaborative, dialogic practices in groups and teams, for instance combined with the use of roleplaying. In the work...... with the thesis, dialogically based practices inspired by action research with the aim to enhance collaborative knowledge building, reflexivity and dialogical skills in groups and teams were carried out, analyzed and documented. Participants included school principals, leaders of kindergartens, teachers...

  14. Leading Hadron Production at HERA

    Directory of Open Access Journals (Sweden)

    Buniatyan Armen

    2013-06-01

    Full Text Available Data from the recent measurements of very forward baryon and photon production with the H1 and ZEUS detectors at electron-proton collider HERA are presented and compared to the theoretical calculations and Monte Carlo models. Results are presented of the production of leading protons, neutrons and photons in deep inelastic scattering (ep → e' pX, ep → e'nX, ep → e'γX as well as the leading neutron production in the photoproduction of dijets (ep → ejjXn. The forward baryon and photon results from the H1 and ZEUS Experiments are compared also with the models of the hadronic interactions of high energy Cosmic Rays. The sensitivity of the HERA data to the differences between the models is demonstrated.

  15. [Noroviruses: leading cause of gastroenteritis].

    Science.gov (United States)

    Delacour, H; Dubrous, P; Koeck, J L

    2010-04-01

    Although noroviruses were the first viral agents to be linked to gastrointestinal disease, they were long considered a secondary cause far behind rotaviruses. Development of molecular-based diagnostic techniques has provided clearer insight into the epidemiological impact of noroviruses that are now recognized not only as the leading cause of non-bacterial gastroenteritis outbreaks but also as an important cause of sporadic gastroenteritis in both children and adults. Norovirus infection is generally characterized by mild acute vomiting and diarrhea usually lasting for only a few days, but it can lead to more severe and potentially life-threatening symptoms in high-risk groups such as young children, elderly, and immunodeficient persons. It has been demonstrated that they are present in tropical countries. Molecular epidemiological studies have documented the great genetic diversity of noroviruses with regular emergence of variants. Since no vaccine is available, prevention on norovirus infection depends mainly on strict personal and community hygiene measures.

  16. Deformation properties of lead isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Tolokonnikov, S. V.; Borzov, I. N.; Lutostansky, Yu. S.; Saperstein, E. E., E-mail: saper43-7@mail.ru [National Research Center Kurchatov Institute (Russian Federation)

    2016-01-15

    The deformation properties of a long lead isotopic chain up to the neutron drip line are analyzed on the basis of the energy density functional (EDF) in the FaNDF{sup 0} Fayans form. The question of whether the ground state of neutron-deficient lead isotopes can have a stable deformation is studied in detail. The prediction of this deformation is contained in the results obtained on the basis of the HFB-17 and HFB-27 Skyrme EDF versions and reported on Internet. The present analysis reveals that this is at odds with experimental data on charge radii and magnetic moments of odd lead isotopes. The Fayans EDF version predicts a spherical ground state for all light lead isotopes, but some of them (for example, {sup 180}Pb and {sup 184}Pb) prove to be very soft—that is, close to the point of a phase transition to a deformed state. Also, the results obtained in our present study are compared with the predictions of some other Skyrme EDF versions, including SKM*, SLy4, SLy6, and UNE1. By and large, their predictions are closer to the results arising upon the application of the Fayans functional. For example, the SLy4 functional predicts, in just the same way as the FaNDF{sup 0} functional, a spherical shape for all nuclei of this region. The remaining three Skyrme EDF versions lead to a deformation of some light lead isotopes, but their number is substantially smaller than that in the case of the HFB-17 and HFB-27 functionals. Moreover, the respective deformation energy is substantially lower, which gives grounds to hope for the restoration of a spherical shape upon going beyond the mean-field approximation, which we use here. Also, the deformation properties of neutron-rich lead isotopes are studied up to the neutron drip line. Here, the results obtained with the FaNDF{sup 0} functional are compared with the predictions of the HFB-17, HFB-27, SKM*, and SLy4 Skyrme EDF versions. All of the EDF versions considered here predict the existence of a region where neutron

  17. String Formation Beyond Leading Colour

    CERN Document Server

    Christiansen, Jesper R.

    2015-08-03

    We present a new model for the hadronisation of multi-parton systems, in which colour correlations beyond leading $N_C$ are allowed to influence the formation of confining potentials (strings). The multiplet structure of $SU(3)$ is combined with a minimisation of the string potential energy, to decide between which partons strings should form, allowing also for "baryonic" configurations (e.g., two colours can combine coherently to form an anticolour). In $e^+e^-$collisions, modifications to the leading-colour picture are small, suppressed by both colour and kinematics factors. But in $pp$ collisions, multi-parton interactions increase the number of possible subleading connections, counteracting their naive $1/N_C^2$ suppression. Moreover, those that reduce the overall string lengths are kinematically favoured. The model, which we have implemented in the PYTHIA 8 generator, is capable of reaching agreement not only with the important $\\left(n_\\mathrm{charged})$ distribution but also with measured rates (and ra...

  18. Misled about lead: an assessment of online public health education material from Australia's lead mining and smelting towns.

    Science.gov (United States)

    Sullivan, Marianne; Green, Donna

    2016-01-06

    This study assesses the accuracy and comprehensiveness of online public health education materials from the three Australian cities with active lead mines and or smelters: Broken Hill, Mount Isa and Port Pirie. Qualitative content analysis of online Australian material with comparison to international best practice where possible. All materials provided incomplete information about the health effects of lead and pathways of exposure compared to best practice materials. Inconsistent strategies to reduce exposure to lead were identified among the Australian cities, and some evidence-based best practices were not included. The materials normalised environmental lead and neglected to identify that there is no safe level of lead, or that primary prevention is the best strategy for protecting children's health. Health education materials need to clearly state health risks from lead across developmental stages and for sensitive populations, integrate a primary prevention perspective, and provide comprehensive evidence-based recommendations for reducing lead exposure in and around the home. Families who rely on information provided by these online public education materials are likely to be inadequately informed about the importance of protecting their children from exposure to lead and strategies for doing so.

  19. Evaluation for leaded and unleaded Gasoline as Hazardous Waste

    International Nuclear Information System (INIS)

    Abou El Naga, H.H.

    1999-01-01

    With the phase out of alkyl lead compounds as necessary additives for gasoline in order to raise its octane number , the alternative is to reformulate gasoline to have nearly same octane number but with other chemical structures. Such reformulated gasoline (RFG) is found to contain higher aromatics, benzene, iso paraffins, in comparison to leaded gasoline. Additionally, this reformulated gasoline can also contain oxygenated additives. Accordingly, this paper is aiming at evaluation of emitted hazardous chemical compounds from car engines at fuel combustion. Role of chemical structures for reformulated gasoline in emission of volatile organic compounds (VOC) and poisoning materials are considered

  20. Lead and cadmium in food

    International Nuclear Information System (INIS)

    Gliesmann, S.; Kruse, H.; Kriews, M.; Mangels, H.

    1992-08-01

    The amounts of lead and cadmium produced and processed in these days are considerable. As a result, our environment is increasingly polluted by heavy metals and industrial installations, motor vehicles or incinerating plants appear to be among the main culprits here. Air and water are the media permitting the entry of heavy metals into our natural environment where they accumulate in the soil and then gradually migrate into the plants. Their further transport in the food constitutes the third step in the environmental spread of heavy metals. The consumption of muscle and organ meats, of vegetables, fruits, canned food and drinking water is unavoidably associated with some ingestion of lead and cadmium. The degree to which they are taken up and stored in different tissues is determined by absorption properties and the nutritional state of the organism. Cadmium tends to accumulate in the kidneys, lead is mainly stored in the bones. A continuously increasing uptake finally results in health injuries that range from unspecific complaints to damaged kidneys or bones and disorders of liver function. Children and elderly people are at a particular risk here. The level of food contamination is such that screening for heavy metals must be rigorously carried out once appropriate legal thresholds have been set, which ought to be based on proven detrimental effects of lead and cadmium on our health and also take account of infants and children or any other risk groups, where particular caution must be exercised. It should be pointed out that such thresholds have so far not been determined. (orig./MG) [de

  1. Leading Indian Business-Groups

    Directory of Open Access Journals (Sweden)

    Maria Alexandrovna Vorobyeva

    2016-01-01

    Full Text Available The goal of this paper is to investigate the evolution of the leading Indian business-groups under the conditions of economical liberalization. It is shown that the role of modern business-groups in the Indian economy is determined by their high rate in the gross domestic product (GDP, huge overall actives, substantial pert in the e[port of goods and services, as well as by their activities in modern branch structure formatting, and developing labor-intensive and high-tech branches. They strongly influence upon economical national strategies, they became a locomotive of internationalization and of transnationalization of India, the basis of the external economy factor system, the promoters of Indian "economical miracle" on the world scene, and the dynamical segment of economical and social development of modern India. The tendencies of the development of the leading Indian business groups are: gradual concentration of production in few clue sectors, "horizontal" structure, incorporation of the enterprises into joint-stock structure, attraction of hired top-managers and transnationaliziation. But against this background the leading Indian business-groups keep main traditional peculiarities: they mostly still belong to the families of their founders, even today they observe caste or communal relations which are the basis of their non-formal backbone tides, they still remain highly diversificated structures with weak interrelations. Specific national ambivalence and combination of traditions and innovations of the leading Indian business-groups provide their high vitality and stability in the controversial, multiform, overloaded with caste and confessional remains Indian reality. We conclude that in contrast to the dominant opinion transformation of these groups into multisectoral corporations of the western type is far from completion, and in the nearest perspective they will still possess all their peculiarities and incident social and economical

  2. Tevatron HTS power lead test

    International Nuclear Information System (INIS)

    Feher, S.; Carcagno, R.; Orris, D.; Pischalnikov, Y.; Sylvester, C.; Tartaglia, M.; Tompkins, J.C.

    2004-01-01

    Two pairs of ASC 6 kA power leads developed for the Tevatron were successfully tested at Fermilab at over-current conditions. Stable operation was achieved while operating at a current of 9.56 kA for five hours and while continuously ramping between 0-9.56 kA at a ramp rate of 200 A/s for one hour. The minimum required liquid nitrogen flow rate was measured to be 1.5 g/s at 10 kA. After ramping up to 10 kA at 200A/s, it took only 15 minutes to stabilize the upper copper section of the lead with a flow of 1.8 g/s of liquid nitrogen vapor. Testing under extreme operating conditions--270-370 kPa liquid nitrogen vapor pressure and over 0.1 T external magnetic field--demonstrated that the HTS part of the lead can safely operate in the current sharing mode and that this design has large operating margin

  3. The LHC Lead Injector Chain

    CERN Document Server

    Beuret, A; Blas, A; Burkhardt, H; Carli, Christian; Chanel, M; Fowler, A; Gourber-Pace, M; Hancock, S; Hourican, M; Hill, C E; Jowett, John M; Kahle, K; Küchler, D; Lombardi, A M; Mahner, E; Manglunki, Django; Martini, M; Maury, S; Pedersen, F; Raich, U; Rossi, C; Royer, J P; Schindl, Karlheinz; Scrivens, R; Sermeus, L; Shaposhnikova, Elena; Tranquille, G; Vretenar, Maurizio; Zickler, T

    2004-01-01

    A sizeable part of the LHC physics programme foresees lead-lead collisions with a design luminosity of 1027 cm-2 s-1. This will be achieved after an upgrade of the ion injector chain comprising Linac3, LEIR, PS and SPS machines [1,2]. Each LHC ring will be filled in 10 min by almost 600 bunches, each of 7×107 lead ions. Central to the scheme is the Low Energy Ion Ring (LEIR) [3,4], which transforms long pulses from Linac3 into high-brilliance bunches by means of multi-turn injection, electron cooling and accumulation. Major limitations along the chain, including space charge, intrabeam scattering, vacuum issues and emittance preservation are highlighted. The conversion from LEAR (Low Energy Antiproton Ring) to LEIR involves new magnets and power converters, high-current electron cooling, broadband RF cavities, and a UHV vacuum system with getter (NEG) coatings to achieve a few 10-12 mbar. Major hardware changes in Linac3 and the PS are also covered. An early ion scheme with fewer bunches (but each at nominal...

  4. Natural convection in enclosures containing lead-bismuth and lead

    International Nuclear Information System (INIS)

    Dzodzo, M.; Cuckovic-Dzodzo, D.

    2001-01-01

    The design of liquid metal reactors such as Encapsulated Nuclear Heat Source (ENHS) which are based predominantly on the flow generated by natural convection effects demands knowledge of velocity and temperature fields, distribution of the local Nusselt numbers and values of the average Nusselt numbers for small coolant velocity regimes. Laminar natural convection in rectangular enclosures with different aspect ratios, containing lead-bismuth and lead is studied numerically in this paper. The numerical model takes into account variable properties of the liquid metals. The developed correlation for average Nusselt numbers is presented. It is concluded that average Nusselt numbers are lower than in 'normal' fluids (air, water and glycerol) for the same values of Rayleigh numbers. However, the heat flux, which can be achieved, is greater due to the high thermal conductivity of liquid metals. Some specific features of the flow fields generated by natural convection in liquid metals are presented. Their consequences on the design of heat exchangers for liquid metals are discussed. An application of the obtained results to the design of a new type of steam generator, which integrates the intermediate heat exchanger and secondary pool functions of the ENHS reactor, is presented. (authors)

  5. Correlations in particle production in proton-lead and lead-lead collisions at the LHC

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00361447

    In high-energy heavy-ion collisions at the Large Hadron Collider (LHC), a hot and dense state of matter called the Quark-Gluon Plasma (QGP) is formed. The initial collision geometry and the subsequent expansion during the QGP stage result in the correlations of produced particles, through which the properties of the QGP can be investigated. Two analyses based on the geometrical correlations of produced particles, one in proton-lead (p–Pb) collisions and the other in lead-lead (Pb–Pb) collisions, are presented in this thesis. The data analyzed in this thesis were collected with the ALICE detector at the LHC in p– Pb collisions at a nucleon–nucleon center-of-mass energy of 5.02 TeV, and Pb–Pb collisions at a nucleon–nucleon center-of-mass energy of 2.76 TeV. In the forward-central two-particle correlation analysis in p–Pb collisions, two-particle an- gular correlations between trigger particles in the forward pseudorapidity range (2.5 < |η| < 4.0) and associated particles in the central ran...

  6. Leading Baryon Production at HERA

    International Nuclear Information System (INIS)

    Dodonov, V.; Schmitt, S.

    2009-01-01

    The production of highly energetic forward neutrons has been studied in deep-inelastic scattering. The data were taken with the H1 detector at HERA in the years 2006-2007 and correspond to an integrated luminosity of 117 pb -1 . Semi-inclusive cross sections have been measured in the kinematic region 4 2 2 , 0.7*10 -4 -1 and the fractional momentum of the neutron 0.3 L T and compared to the predictions of models of leading neutron production. Differential cross sections for dijet photoproduction and in association with a leading neutron have been measured in the reaction e + p → e + jet jet X n with the ZEUS detector at HERA using an integrated luminosity of 40pb -1 . The data are consistent with a simple pion exchange model. The ratio of the neutron-tagged and dijet cross sections show violations of factorization of the lepton and photon vertices which can be explained by kinematic effects constraining the phase space for neutron production. Normalised double-differential leading-neutron cross sections have been measured in dijet photoproduction for the first time. The distributions can be fully characterised by only two energy dependent parameters extracted from fits to the data. Absorption effects were studied by comparing the dijet photoproduction measurements and similar results in deep inelastic scattering. No clear effect, not related to kinematics, was observed. In a resolved-enriched dijet photoproduction sample, significantly fewer neutrons were seen than for direct. This depletion can also be accounted for by kinematic constraints. The semi-inclusive reaction e + p → e + X p was studied with the ZEUS detector at HERA using an integrated luminosity of 12.8 pb -1 . The final state proton, which was detected with the ZEUS leading proton spectrometer, carried a large fraction of the incoming proton energy, x L > 0.32, and its transverse momentum squared satisfied p T 2 2 ; the exchanged photon virtuality, Q 2 , was greater than 3 GeV 2 and the range of

  7. The art of leading meetings.

    Science.gov (United States)

    English, C B

    1987-05-01

    The ability to skillfully lead meetings can contribute to a manager's effectiveness. There are four types of meetings, each serving different needs and requiring different leadership. A manager must know when to hold meetings, what leadership style is appropriate, how and when to use participative management, and how to facilitate a consensus. Considerable planning must be done before a meeting is held. Various leadership and communication skills are required to effectively open, conduct, and close a meeting. Finally, the leader needs to know how to deal with participants who become problems.

  8. Lead-nickel electrochemical batteries

    CERN Document Server

    Glaize, Christian

    2012-01-01

    The lead-acid accumulator was introduced in the middle of the 19th Century, the diverse variants of nickel accumulators between the beginning and the end of the 20th Century. Although old, these technologies are always very present on numerous markets. Unfortunately they are still not used in optimal conditions, often because of the misunderstanding of the internal electrochemical phenomena.This book will show that batteries are complex systems, made commercially available thanks to considerable amounts of scientific research, empiricism and practical knowledge. However, the design of

  9. Lead reactor strategy economical analysis

    International Nuclear Information System (INIS)

    Ciotti, Marco

    2013-01-01

    Conclusions: • A first attempt to evaluate LFR power plant electricity production cost has been performed; • Electricity price is similar to Gen III + plants; • The estimation accuracy is probably low; • Possible costs reduction could arise from coolant characteristics that may improve safety and simplicity by design; • Accident perception, not acceptable by public opinion, may be changed with low potential energy system (non exploding coolant); • Sustainability improvement could open to a better Public acceptance, depending on us. • Problems may arise in coupling a high capital cost low fuel cost plant in a grid with large amount of intermittent sources with priority dispatch. • Lead fast reactors can compete

  10. Soft mode of lead zirconate

    International Nuclear Information System (INIS)

    Pan'ko, G.F.; Prisedskij, V.V.; Klimov, V.V.

    1983-01-01

    Anisotropic diffusional scattering of electrons on PbZrO 3 crystal in the temperature range of phase transition has been recorded. As a result of its analysis it has been established that in lead zirconate the rotational vibrational mode G 25 plays the role of soft mode. The experiment is carried out using PbZrO 3 monocrystals in translucent electron microscope EhM-200, operating in the regime of microdiffraction at accelerating voltage of 150 kV and beam current 50 μA; sample preparation is realized using the method of shearing and fragmentation

  11. Pregnancy increases mobilisation of lead from maternal skeleton

    International Nuclear Information System (INIS)

    Gulson, B.L.

    2000-01-01

    Lead is a neurotoxin that, even at low levels, is considered to result in neurobehavioural disorders such as cognitive deficits, learning disability and behavioural disturbances. The most recent study of Needleman et al. suggested an association between bone lead levels and antisocial and delinquent behaviour (Needleman et al., 1996). Although the neurobehavioural deficits associated with low-level lead exposure are best documented for early childhood exposures, the effects of lead on the developing nervous system are of concern. Lead readily crosses the placenta (Barltrop, 1969; Silbergeld, 1991) and changes in maternal blood lead potentially result in alterations to foetal exposure. Mobilisation of lead from body stores accumulated prior to pregnancy has been established in experimental animals (Buchet, 1977; Keller and Doherty, 1980). The cohort was to consist of 100 immigrants anticipated to provide 20 pregnant subjects who would be compared with two groups of control subjects: a matched immigrant nonpregnant control group and second-generation Australian pregnant controls. The pregnant subject also serves as her own control for a comparison of changes during pregnancy with those prior to conception. High precision lead isotopic compositions and lead concentrations were measured on: maternal blood and urine prenatally, monthly during pregnancy and post-pregnancy for 6 months; infant blood and urine for 6 months; and environmental measures sampled quarterly for 6-day duplicate diet, house dust and water, urban air and petrol. Results of this study confirm that lead is mobilised from skeletal stores at an accelerated rate during pregnancy and transferred to the foetus. This has implications for interpretations of neurobehavioural disorders attributed solely to post-natal exposure

  12. String formation beyond leading colour

    Energy Technology Data Exchange (ETDEWEB)

    Christiansen, Jesper R. [Department of Astronomy and Theoretical Physics, Lund University,Sölvegatan 14, Lund (Sweden); Theoretical Physics, CERN,CH-1211, Geneva 23 (Switzerland); Skands, Peter Z. [Theoretical Physics, CERN,CH-1211, Geneva 23 (Switzerland); School of Physics and Astronomy, Monash University,VIC-3800 (Australia)

    2015-08-03

    We present a new model for the hadronisation of multi-parton systems, in which colour correlations beyond leading N{sub C} are allowed to influence the formation of confining potentials (strings). The multiplet structure of SU(3) is combined with a minimisation of the string potential energy, to decide between which partons strings should form, allowing also for “baryonic” configurations (e.g., two colours can combine coherently to form an anticolour). In e{sup +}e{sup −}collisions, modifications to the leading-colour picture are small, suppressed by both colour and kinematics factors. But in pp collisions, multi-parton interactions increase the number of possible subleading connections, counteracting their naive 1/N{sub C}{sup 2} suppression. Moreover, those that reduce the overall string lengths are kinematically favoured. The model, which we have implemented in the PYTHIA 8 generator, is capable of reaching agreement not only with the important 〈p{sub ⊥}〉(n{sub charged}) distribution but also with measured rates (and ratios) of kaons and hyperons, in both ee and pp collisions. Nonetheless, the shape of their p{sub ⊥} spectra remains challenging to explain.

  13. Lead -- supply/demand outlook

    International Nuclear Information System (INIS)

    Schnull, T.

    1999-01-01

    As Japan goes--so goes the world. That was the title of a recent lead article in The Economist that soberly discussed the potential of much more severe global economic problems occurring, if rapid and coordinated efforts were not made to stabilize the economic situation in Asia in general, and in Japan in particular. During the first 6 months of last year, commodity markets reacted violently to the spreading economic problems in Asia. More recent currency and financial problems in Russia have exacerbated an already unpleasant situation. One commodity after another--including oil, many of the agricultural commodities, and each of the base metals--have dropped sharply in price. Many are now trading at multiyear lows. Until there is an overall improvement in the outlook for these regions, sentiment will likely continue to be negative, and metals prices will remain under pressure. That being said, lead has maintained its value better than many other commodities during these difficult times, finding support in relatively strong fundamentals. The author takes a closer look at those supply and demand fundamentals, beginning with consumption

  14. All roads lead to Meyrin

    CERN Multimedia

    Communication locale

    2011-01-01

    Tous les chemins mènent à Meyrin - All roads lead to Meyrin From 29 September to 16 October, 2011, come to the Salle Antoine Verchère in Meyrin for Tous les chemins mènent à Meyrin. The celebration will include an exposition as well as a theatrical performance about Meyrin, the first satellite city in Switzerland. With the help of the memories and testimonies from the people of Meyrin, Tous les chemins mènent à Meyrin is putting the collective memories of the commune on display. It is an occasion for everyone, whether you're from near or far, to find out how all the roads lead to Meyrin.  Salle Antoine-Verchère Route de Meyrin 294 – 1217 Meyrin Tram 18 – Stop: Meyrin Village Thursdays / Fridays / Saturdays at 8pm Sundays at 5pm Regular ticket: CHF 15.- Concession ticket (students, chômeurs, AVS, AI): CHF 12.- Children up to 16: CHF 10.- Family ticket: CHF 35.-

  15. Finland's leading natural gas company

    International Nuclear Information System (INIS)

    Anon.

    2000-01-01

    The ownership structure of Finland's leading natural gas company, Gasum, changed fundamentally in 1999, and the company is now no longer a subsidiary of Fortum Corporation. 'Our new strong and broad ownership base will enable us to develop the natural gas business and pipeline network in Finland in response to the requirements of our Finnish customers', says Antero Jaennes, Gasum's Chairman and CEO, who stresses that Gasum is committed to remaining the leading developer of the Finnish natural gas market and the number-one gas supplier. Natural gas usage in Finland in 1999 totalled 3.9 billion m 3 (38.7 TWh), unchanged from 1998. Natural gas accounted for 11% of Finland's total primary energy need, as it did in 1998. The proportion of natural gas used in district heating rose by 2% to 36%, and moved down 2% in power generation to 10%. Industry's use of natural gas fell 1% to 17%. 75% of natural gas was used in combined heat and power (CHP) generation in industry and district heating. In 2000, Gasum expects to sell 4 billion m 3 of natural gas (40 TWh)

  16. Recycling abandoned lead battery sites

    International Nuclear Information System (INIS)

    Montgomery, A.H.

    1993-01-01

    In the past, automobile batteries were recycled principally for their lead content. The waste generated at battery wrecking facilities consisted of spent acid, crushed casings (ebonite and plastic), and where secondary smelting was involved, matte, slag, and carbon from the smelting process. These waste products were generally disposed in an on-site in a landfill or stored in piles. If the facility shut down because further commercial operations were not financially viable, the waste piles remained to be addressed at a later date through remedial action or reclamation programs. There are many of these facilities in the US. Nationally, about 28 sites have been discovered by the US Environmental Protection Agency (EPA) under the Superfund program and are under investigation or administrative orders for remedial action. A major remediation effort is now underway at the Gould Superfund Site in Portland, Oregon, which was operated as a secondary smelting facility between 1949 and 1981. This paper describes the nature of the contamination at the Gould site and the work conducted by Canonie Environmental Services Corp. (Canonie) to develop a process which would treat the waste from battery wrecking operations and produce revenue generating recyclable products while removing the source contamination (lead) from the site. The full-scale commercial plant is now operating and is expected to achieve a throughput rate of between 200 and 250 tons per day in the coming weeks

  17. Lead pollution, disease, and behaviour

    Energy Technology Data Exchange (ETDEWEB)

    Bryce-Smith, D; Waldron, H A

    1974-01-01

    Sources and health effects of atmospheric lead pollution are reviewed. Most of the Pb in gasoline is emitted in the exhaust gases as an aerosol containing particles of inorganic Pb. Some organic Pb is present, but the amount is usually less than 10% of the total. The size of these particles (0.18 to 0.90 micron) ensures maximum pulmonary penetration and absorption. The fallout of airborne particles produces very high concentrations of Pb in city dust, both inside and outside houses. Unpolluted soil contains about 15 ppM Pb, but samples of city dust contain 1000 to 6000 ppM. A daily intake of as little as 30 mg of dust containing 3% Pb produces clinical Pb poisoning in a few months. There is clear evidence to support the thesis that current levels in the environment are capable of producing behavioral abnormalities of types associated with educational disorders and delinquency, and also evidence that delinquents tend to have abnormal lead metabolism.

  18. Fracture mechanisms in lead zirconate titanate ceramics

    International Nuclear Information System (INIS)

    Freiman, S.W.; Chuck, L.; Mecholsky, J.J.; Shelleman, D.L.

    1986-01-01

    Lead Zirconate Titanate (PZT) ceramics can be formed over a wide range of PbTiO 3 /PbZrO 3 ratios and exist in a number of crystal structures. This study involved the use of various fracture mechanics techniques to determine critical fracture toughness, K /SUB IC/ , as a function of composition, microstructure, temperature, and electrical and thermal history. The results of these experiments indicate that variations in K /SUB IC/ are related to phase transformations in the material as well as to other toughening mechanisms such as twinning and microcracking. In addition, the strength and fracture toughness of selected PZT ceramics were determined using specimens in which a crack was introduced by a Vicker's hardness indentor. The variation of K /SUB IC/ with composition and microstructure was related to the extent of twin-crack interaction. Comparison of the plot of strength as a function of indentation load with that predicted from indentation fracture models indicates the presence of internal stresses which contribute to failure. The magnitude of these internal stresses has been correlated with electrical properties of the ceramic. Fractographic analysis was used to determine the magnitude of internal stresses in specimens failing from ''natural flaws.''

  19. Lead isotope profiling in dairy calves.

    Science.gov (United States)

    Buchweitz, John; McClure-Brinton, Kimberly; Zyskowski, Justin; Stensen, Lauren; Lehner, Andreas

    2015-03-01

    Lead (Pb) is a common cause of heavy metal poisonings in cattle. Sources of Pb on farms include crankcase oil, machinery grease, batteries, plumbing, and paint chips. Consequently, consumption of Pb from these sources may negatively impact animal health and Pb may be inadvertently introduced into the food supply. Therefore, the scope of poisoning incidents must be clearly assessed and sources of intoxication identified and strategies to mitigate exposure evaluated and implemented to prevent future exposures. Stable isotope analysis by inductively-coupled plasma mass spectrometry (ICP-MS) has proven itself of value in forensic investigations. We report on the extension of Pb stable isotope analysis to bovine tissues and profile comparisons with paint chips and soils collected from an affected dairy farm to elucidate the primary source. Pb occurs naturally as four stable isotopes: (204)Pb, (206)Pb, (207)Pb, and (208)Pb. Herein a case is reported to illustrate the use of (207)Pb/(206)Pb and (208)Pb/(206)Pb ratios to link environmental sources of exposure with tissues from a poisoned animal. Chemical Pb profiling provides a valuable tool for field investigative approaches to Pb poisoning in production agriculture and is applicable to subclinical exposures. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Glasses impregnated with lead for radiation shielding

    International Nuclear Information System (INIS)

    Abd El Monem, A.M.; Kansouh, W.A.; Megahid, R.M.; Ismail, A.L.; Awad, E.M.

    2005-01-01

    The attenuation properties of glasses with different concentration of lead have been investigated for the attenuation of gamma-rays from cesium-137 and for total gamma rays using a beam of neutrons and gamma rays emitted from californium-252 source. Measurements have been performed using a gamma-ray spectrometer with Nal(T1) detector for gamma-rays emitted from 137 Cs and a neutron/gamma spectrometer with stilbene scintillator for measurement of total gamma-rays from 252 Cf neutron source. The latter applied the pulse shape discrimination technique to distinguish between recoil proton and recoil electron pulses. The obtained results given the form displayed pulse height spectra and attenuation relations which were used to derive the linear attenuation coefficient (μ), and the mass attenuation coefficient (mu/p) of the investigated glasses. In addition, calculations were performed to determine the attenuation properties of glass shields under investigation using XCOM code given by the others. A comparison of the shielding properties of these glasses with some standard shielding materials indicated that, the investigated glasses process the shielding advantages required for different nuclear technology applications

  1. What is lead-based paint?

    International Nuclear Information System (INIS)

    Vernon, L.S.

    1994-01-01

    The number of variety of lead-abatement regulations and requirements make it difficult and confusing to identify and properly respond to dangerous levels of lead in every situation. Definitions of ''lead-based paint'' and three test methods for lead detection are described to help determine when and how to test for the presence of lead

  2. Comparative assessment of thermophysical and thermohydraulic characteristics of lead, lead-bismuth and sodium coolants for fast reactors

    International Nuclear Information System (INIS)

    2002-06-01

    All prototype, demonstration and commercial liquid metal cooled fast reactors (LMFRs) have used liquid sodium as a coolant. Sodium cooled systems, operating at low pressure, are characterised by very large thermal margins relative to the coolant boiling temperature and a very low structural material corrosion rate. In spite of the negligible thermal energy stored in the liquid sodium available for release in case of leakage, there is some safety concern because of its chemical reactivity with respect to air and water. Lead, lead-bismuth or other alloys of lead, appear to eliminate these concerns because the chemical reactivity of these coolants with respect to air and water is very low. Some experts believe that conceptually, these systems could be attractive if high corrosion activity inherent in lead, long term materials compatibility and other problems will be resolved. Extensive research and development work is required to meet this goal. Preliminary studies on lead-bismuth and lead cooled reactors and ADS (accelerator driven systems) have been initiated in France, Japan, the United States of America, Italy, and other countries. Considerable experience has been gained in the Russian Federation in the course of development and operation of reactors cooled with lead-bismuth eutectic, in particular, propulsion reactors. Studies on lead cooled fast reactors are also under way in this country. The need to exchange information on alternative fast reactor coolants was a major consideration in the recommendation by the Technical Working Group on Fast Reactors (TWGFRs) to collect, review and document the information on lead and lead-bismuth alloy coolants: technology, thermohydraulics, physical and chemical properties, as well as to make an assessment and comparison with respective sodium characteristics

  3. Lead poisoning in small animals

    Energy Technology Data Exchange (ETDEWEB)

    Scott, H M

    1963-08-17

    During the period 1957 to 1959 a considerable number of dogs were seen which were suffering from colic. Colic is not normally a condition commonly encountered in the dog, and the number of cases seen was large in proportion to the number of dogs in the population concerned. A number of other dogs exhibited nervous signs which varied from symptoms of mild anxiety to exaggerated fits. There was a certain amount of overlapping between the 2 groups in that some cases which originally only showed signs of colic later progressed to the stage where they showed nervous symptoms. The following report deals with 28 cases of lead poisoning in dogs and cats which occurred at Broken Hill, Northern Rhodesia. 8 references, 4 tables.

  4. Anti-cancer Lead Molecule

    KAUST Repository

    Sagar, Sunil

    2014-04-17

    Derivatives of plumbagin can be selectively cytotoxic to breast cancer cells. Derivative `A` (Acetyl Plumbagin) has emerged as a lead molecule for testing against estrogen positive breast cancer and has shown low hepatotoxicity as well as overall lower toxicity in nude mice model. The toxicity of derivative `A` was determined to be even lower than vehicle control (ALT and AST markers). The possible mechanism of action identified based on the microarray experiments and pathway mapping shows that derivative `A` could be acting by altering the cholesterol-related mechanisms. The low toxicity profile of derivative `A` highlights its possible role as future anti-cancer drug and/or as an adjuvant drug to reduce the toxicity of highly toxic chemotherapeutic drugs

  5. Anti-cancer Lead Molecule

    KAUST Repository

    Sagar, Sunil; Kaur, Mandeep; Esau, Luke E.

    2014-01-01

    Derivatives of plumbagin can be selectively cytotoxic to breast cancer cells. Derivative `A` (Acetyl Plumbagin) has emerged as a lead molecule for testing against estrogen positive breast cancer and has shown low hepatotoxicity as well as overall lower toxicity in nude mice model. The toxicity of derivative `A` was determined to be even lower than vehicle control (ALT and AST markers). The possible mechanism of action identified based on the microarray experiments and pathway mapping shows that derivative `A` could be acting by altering the cholesterol-related mechanisms. The low toxicity profile of derivative `A` highlights its possible role as future anti-cancer drug and/or as an adjuvant drug to reduce the toxicity of highly toxic chemotherapeutic drugs

  6. Leading multi-soft limits from scattering equations

    Science.gov (United States)

    Zlotnikov, Michael

    2017-10-01

    A Cachazo-He-Yuan (CHY) type formula is derived for the leading gluon, bi-adjoint scalar ϕ 3, Yang-Mills-scalar and non-linear sigma model m-soft factors S m in arbitrary dimension. The general formula is used to evaluate explicit examples for up to three soft legs analytically and up to four soft legs numerically via comparison with amplitude ratios under soft kinematics. A structural pattern for gluon m-soft factor is inferred and a simpler formula for its calculation is conjectured. In four dimensions, a Cachazo-Svrček-Witten (CSW) recursive procedure producing the leading m-soft gluon factor in spinor helicity formalism is developed as an alternative, and Britto-Cachazo-Feng-Witten (BCFW) recursion is used to obtain the leading four-soft gluon factor for all analytically distinct helicity configurations.

  7. Is Your Child Safe from Lead Poisoning?

    Centers for Disease Control (CDC) Podcasts

    In this podcast, Dr. Mary Jean Brown, chief of CDC's Lead Poisoning and Prevention Program, discusses the importance of testing children for lead poisoning, who should be tested, and what parents can do to prevent lead poisoning.

  8. Lead pollution: effects on chlorophyll. [Phalaris canariensis, Lemna minor, graminaceae

    Energy Technology Data Exchange (ETDEWEB)

    Fiussello, N

    1973-01-01

    The emissions of motors are responsible for the high concentrations of lead in soil and plants near roads. In man, when the concentration of lead in blood exceeds the value of 30 ..mu..g/100 ml, is shown a decrease of haemaglobin and an increase of ALA urinary content. Since the early stages of chlorophyll biosynthetic pathway are similar if not identical with those leading to haem as far as protoporphyrin IX, it is interesting to ascertain if lead can specifically interfere in chlorophyll biosynthesis. In sand cultures with 200 p.p.m. of lead (the conc. in roadside soils), after 2 weeks, wheat shows a diminution of 16,5% in fresh weight 7,5% in dry weight and 6,5% in chlorophyll; Phalaris canariensis shows a diminution of 68% f.w., 41% d.w. and 39% chl. in comparison with the controls. A water-plant, Lemna minor, is more sensitive: the chlorophyll content, referred to dry weight, shows after a week a diminution of 32% and 55% with 10/sup -4/M and 10/sup -3/M lead nitrate. Lead in 200 p.p.m. conc. is surely poisonous against the tested plants but a specific action on chlorophyll synthesis could be accepted, at present, only for Lemna minor. It is possible that in wheat and in Phalaris a part of lead is bound in root-system, the more damaged, while in Lemna it can reach more easily the chloroplasts. At present a detectable increase of ALA, in plants treated with lead, has not been proved both in Graminaceae and in Lemna minor.

  9. Heavy flavour production in proton-lead and lead-lead collisions with LHCb

    Science.gov (United States)

    Winn, Michael

    2017-11-01

    The LHCb experiment offers the unique opportunity to study heavy-ion interactions in the forward region (2 kinematic domain complementary to the other 3 large experiments at the LHC. The detector has excellent capabilities for reconstructing quarkonia and open charm states, including baryons, down to zero pT. It can separate the prompt and displaced charm components. In pPb collisions, both forward and backward rapidities are covered thanks to the possibility of beam reversal. Results include measurements of the nuclear modification factor and forward-backward ratio for charmonium, open charm and bottomonium states. These quantities are sensitive probes for nuclear effects in heavy flavour production. Perspectives are given with the large accumulated luminosity during the 2016 pPb run at the LHC. In 2015, LHCb participated successfully for the first time in the PbPb data-taking. The status of the forward prompt J/ψ nuclear modification factor measurement in lead-lead collisions is discussed.

  10. The identification of lead ammunition as a source of lead exposure in First Nations: The use of lead isotope ratios

    International Nuclear Information System (INIS)

    Tsuji, Leonard J.S.; Wainman, Bruce C.; Martin, Ian D.; Sutherland, Celine; Weber, Jean-Philippe; Dumas, Pierre; Nieboer, Evert

    2008-01-01

    The use of lead shotshell to hunt water birds has been associated with lead-contamination in game meat. However, evidence illustrating that lead shotshell is a source of lead exposure in subsistence hunting groups cannot be deemed definitive. This study seeks to determine whether lead shotshell constitutes a source of lead exposure using lead isotope ratios. We examined stable lead isotope ratios for lichens, lead shotshell and bullets, and blood from residents of Fort Albany and Kashechewan First Nations, and the City of Hamilton, Ontario, Canada. Data were analyzed using ANOVA and regression analyses. ANOVA of isotope ratios for blood revealed significant differences with respect to location, but not sex. Hamilton differed from both Kashechewan and Fort Albany; however, the First Nations did not differ from each other. ANOVA of the isotope ratios for lead ammunition and lichens revealed no significant differences between lichen groups (north and south) and for the lead ammunition sources (pellets and bullets). A plot of 206 Pb/ 204 Pb and 206 Pb/ 207 Pb values illustrated that lichens and lead ammunition were distinct groupings and only the 95% confidence ellipse of the First Nations group overlapped that of lead ammunition. In addition, partial correlations between blood-lead levels (adjusted for age) and isotope ratios revealed significant (p 206 Pb/ 204 Pb and 206 Pb/ 207 Pb, and a significant negative correlation for 208 Pb/ 206 Pb, as predicted if leaded ammunition were the source of lead exposure. In conclusion, lead ammunition was identified as a source of lead exposure for First Nations people; however, the isotope ratios for lead shotshell pellets and bullets were indistinguishable. Thus, lead-contaminated meat from game harvested with lead bullets may also be contributing to the lead body burden

  11. Lead bioaccessibility in topsoils from lead mineralisation and urban domains, UK

    International Nuclear Information System (INIS)

    Appleton, J.D.; Cave, M.R.; Palumbo-Roe, B.; Wragg, J.

    2013-01-01

    Predictive linear regression (LR) modelling indicates that total Pb is the only highly significant independent variable for estimating Pb bioaccessibility in “mineralisation domains” located in limestone (high pH) and partly peat covered (low pH) shale-sandstone terrains in England. Manganese is a significant minor predictor in the limestone terrain, whilst organic matter and sulphur explain 0.5% and 2% of the variance of bioaccessible Pb in the peat-shale-sandstone terrain, compared with 93% explained by total Pb. Bootstrap resampling shows that LR confidence limits overlap for the two mineralised terrains but the limestone terrain has a significantly lower bioaccessible Pb to total Pb slope than the urban domain. A comparison of the absolute values of stomach and combined stomach-intestine bioaccessibility provides some insight into the geochemical controls on bioaccessibility in the contrasting soil types. -- Highlights: •Total Pb is the only highly significant predictor for bioaccessible Pb in lead mineralisation domains. •Manganese is a significant minor predictor in limestone terrain. •Organic matter and sulphur are minor predictors in peat-shale-sandstone terrain. •Results can be used for initial risk assessment in Pb mineralisation domain. -- Total Pb is the major predictor for bioaccessible Pb in topsoils from two lead mineralised areas in England

  12. Shorts due to diagnostic leads

    International Nuclear Information System (INIS)

    Ellis, J.F.; Lubell, M.S.; Pillsbury, R.D.; Shen, S.S.; Thome, R.J.; Walstrom, P.L.

    1985-01-01

    The superconducting toroidal field coils that are being tested in the Large Coil Test Facility (LCTF) are heavily instrumented. General Electric coil, a lead wire of an internal sensor became shorted across an estimated three or four turns of the pancake winding. This short occurred during the final stages of the winding fabrication and was not accessible for repair. Resistance, voltage gradient, and transient voltage decay measurements were performed to characterize the short and the magnetic damping of the large steel bobbin and outer structural ring. The 32-gage wire causing the short was estimated to be about 10 cm long, with a resistance of 55 mΩ. As a safety measure, we decided to burn out the shorted wire at room temperature before installing the coil in LCTF. Tests were made to determine the energy needed to vaporize a small wire. Computer calculations indicated that within the voltage limits set for the coil, it was not feasible to burn out the wire by rapidly dumping the coil from a low-current dc charge-up. We accomplished the burnout by applying 800 V at 3.25 A, and 60 Hz for about 1 s. Transient voltage decay measurements made after the burnout and compared with those made before the attempt confirmed that the short had indeed been opened

  13. Leading local politicians visit CERN

    CERN Multimedia

    2001-01-01

    Left to right:  Professor Maiani, Ernest Nycollin, Anne-Marie Comparini, and Jean Pépin surrounded by young PRAC. On the 13th of November leading local politicians : Mme Anne-Marie Comparini, Présidente du Conseil régional de Rhône-Alpes, M. Ernest Nycollin, Président du Conseil général de la Haute-Savoie et M. Jean Pépin, Président du Conseil général de l'Ain took part in a ceremony which featured the insertion of one of the first LHC magnets into its cryostat.  The department of l'Ain financed a large part of the contruction of building SMA 18 which will see intense activity during the assembly of LHC magnets over the next four years. The department of Haute-Savoie helped in the development of the ultrasonic welding machine for the superconducting cables and the conception of integrated circuits that will be used to measure temperature and pressure inside the magnets. T...

  14. Lattice dynamics and dielectric spectroscopy of BZT and NBT lead-free perovskite relaxors - comparison with lead-based relaxors

    Czech Academy of Sciences Publication Activity Database

    Petzelt, Jan; Nuzhnyy, Dmitry; Bovtun, Viktor; Kempa, Martin; Savinov, Maxim; Kamba, Stanislav; Hlinka, Jiří

    2015-01-01

    Roč. 88, č. 3 (2015), 320-332 ISSN 0141-1594 R&D Projects: GA ČR GA13-15110S Institutional support: RVO:68378271 Keywords : relaxor ferroelectrics * polar phonons * polar nanoregions * dielectric spectroscopy * off-centred ions Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.858, year: 2015

  15. Surface dust wipes are the best predictors of blood leads in young children with elevated blood lead levels

    Energy Technology Data Exchange (ETDEWEB)

    Gulson, Brian, E-mail: brian.gulson@mq.edu.au [Graduate School of the Environment, Macquarie University, North Ryde NSW 2109 (Australia); CSIRO Earth Science and Resource Engineering, North Ryde NSW 2113 (Australia); Anderson, Phil [Information and Statistics Group, Australian Institute of Health and Welfare, Canberra ACT 2601 (Australia); Faculty of Health, University of Canberra, Canberra ACT 2601 (Australia); Taylor, Alan [Department of Psychology, Macquarie University, Sydney NSW 2109 (Australia)

    2013-10-15

    Background: As part of the only national survey of lead in Australian children, which was undertaken in 1996, lead isotopic and lead concentration measurements were obtained from children from 24 dwellings whose blood lead levels were ≥15 µg/dL in an attempt to determine the source(s) of their elevated blood lead. Comparisons were made with data for six children with lower blood lead levels (<10 µg/dL). Methods: Thermal ionisation and isotope dilution mass spectrometry were used to determine high precision lead isotopic ratios ({sup 208}Pb/{sup 206}Pb, {sup 207}Pb/{sup 206}Pb and {sup 206}Pb/{sup 204}Pb) and lead concentrations in blood, dust from floor wipes, soil, drinking water and paint (where available). Evaluation of associations between blood and the environmental samples was based on the analysis of individual cases, and Pearson correlations and multiple regression analyses based on the whole dataset. Results and discussion: The correlations showed an association for isotopic ratios in blood and wipes (r=0.52, 95% CI 0.19–0.74), blood and soil (r=0.33, 95% CI −0.05–0.62), and blood and paint (r=0.56, 95% CI 0.09–0.83). The regression analyses indicated that the only statistically significant relationship for blood isotopic ratios was with dust wipes (B=0.65, 95% CI 0.35–0.95); there were no significant associations for lead concentrations in blood and environmental samples. There is a strong isotopic correlation of soils and house dust (r=0.53, 95% CI 0.20–0.75) indicative of a common source(s) for lead in soil and house dust. In contrast, as with the regression analyses, no such association is present for bulk lead concentrations (r=−0.003, 95% CI −0.37–0.36), the most common approach employed in source investigations. In evaluation of the isotopic results on a case by case basis, the strongest associations were for dust wipes and blood. -- Highlights: • Children with elevated blood lead ≥15 µg/dL compared with a group with <10

  16. Results from the Cooler and Lead Tests

    International Nuclear Information System (INIS)

    Green, Michael A.

    2010-01-01

    The report presents the results of testing MICE spectrometer magnet current leads on a test apparatus that combines both the copper leads and the high temperature superconducting (HTS) leads with a single Cryomech PT415 cooler and liquid helium tank. The current is carried through the copper leads from 300 K to the top of the HTS leads. The current is then carried through the HTS leads to a feed-through from the vacuum space to the inside of a liquid helium tank. The experiment allows one to measure the performance of both cooler stages along with the performance of the leads. While the leads were powered we measured the voltage drops through the copper leads, through the HTS leads, through spliced to the feed-through, through the feed-through and through the low-temperature superconducting loop that connects one lead to the other. Measurements were made using the leads that were used in spectrometer magnet 1A and spectrometer magnet 2A. These are the same leads that were used for Superbend and Venus magnets at LBNL. The IL/A for these leads was 5.2 x 10 6 m -1 . The leads turned out to be too long. The same measurements were made using the leads that were installed in magnet 2B. The magnet 2B leads had an IL/A of 3.3 x 10 6 A m -1 . This report discusses the cooler performance and the measured electrical performance of the lead circuit that contains the copper leads and the superconducting leads. All of the HTS leads that were installed in magnet 2B were current tested using this apparatus.

  17. Dietary exposure to lead in the Netherlands

    NARCIS (Netherlands)

    Boon PE; te Biesebeek JD; van Donkersgoed G; VVH; V&Z

    2017-01-01

    Uptake from the soil is the main route by which lead ends up in food. Lead in soil has its origin in both natural and anthropogenic sources. The lead concentration in food has decreased over the last decennia by the use of unleaded petrol and paint, and the replacement of lead water pipes.

  18. Women researchers lead wage hikes

    Science.gov (United States)

    Bell, Peter M.

    Women employed in the research and development fields in universities, government, and industry made substantial increases and lead men in salary gains in 1981, according to a far-reaching survey of 5000 respondents (Industrial Research and Development, April 1982). At the upper end, 20% of women researchers received salary increases of 14% or more, compared to 13% of the men. The raises were high in 1981; more than half the women in research and development had salary gains of over 9%.The employment picture for women in the scientific and technical fields is somewhat complicated by the affirmative efforts of hiring. More women were hired in 1981, and most newly hired women and men begin at the lowest salaries. This factor contributed to the reality that more women than men at the lower salary ranges received zero raises. However, according to the survey, this is not a trend, since the current efforts to add women in research fields are providing more rewards for women per amount of experience than for men: “…women working in R&D have far less experience than their male counterparts.” (IR&D, op cit.). The median years of experience is down in 1981 from previous years. Some 40% of the women surveyed had less than 6 years experience, compared to about 14% of the men. These figures contrast with those of the survey trends of previous years, which indicated a direct relation between salary and experience. It is still true that because larger numbers of men have over 16 years of experience, the highest paid employees in research and development fields are men. It is noted, however, that in the beginning salary scales ($16-27 k/yr) women outnumber men.

  19. Lead isotope analyses of standard rock samples

    International Nuclear Information System (INIS)

    Koide, Yoshiyuki; Nakamura, Eizo

    1990-01-01

    New results on lead isotope compositions of standard rock samples and their analytical procedures are reported. Bromide form anion exchange chromatography technique was adopted for the chemical separation lead from rock samples. The lead contamination during whole analytical procedure was low enough to determine lead isotope composition of common natural rocks. Silica-gel activator method was applied for emission of lead ions in the mass spectrometer. Using the data reduction of 'unfractionated ratios', we obtained good reproducibility, precision and accuracy on lead isotope compositions of NBS SRM. Here we present new reliable lead isotope compositions of GSJ standard rock samples and USGS standard rock, BCR-1. (author)

  20. Measurement of lead compound in stack gas

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Y; Hori, M; Tanikawa, N

    1979-01-01

    The concentration and particle-size distribution of lead compounds in the exhaust gas from various stationary sources are examined. The stationary sources concern lead production from battery scraps, lead smelting of cable mold, steel production from iron scraps, plastic combustion furnace, and a heavy oil boiler. A lead concentration of 0.2-100 mg/cu m in exhaust gas is detected. Furthermore, exhaust gas lead compounds are affected by the raw materials used.

  1. First detection of lead in black paper from intraoral film

    Energy Technology Data Exchange (ETDEWEB)

    Guedes, Debora F.C., E-mail: defcg@usp.br [Departamento de Odontologia Restauradora, Faculdade de Odontologia de Ribeirao Preto, Universidade de Sao Paulo, Av. do Cafe, S/N, Monte Alegre, CEP 14040-904, Ribeirao Preto, SP (Brazil); Silva, Reginaldo S. [Departamento de Odontologia Restauradora, Faculdade de Odontologia de Ribeirao Preto, Universidade de Sao Paulo, Av. do Cafe, S/N, Monte Alegre, CEP 14040-904, Ribeirao Preto, SP (Brazil); Veiga, Marcia A.M.S. da [Departamento de Quimica, Faculdade de Filosofia, Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Av. do Cafe, S/N, Monte Alegre, CEP 14040-904, Ribeirao Preto, SP (Brazil); Pecora, Jesus D. [Departamento de Odontologia Restauradora, Faculdade de Odontologia de Ribeirao Preto, Universidade de Sao Paulo, Av. do Cafe, S/N, Monte Alegre, CEP 14040-904, Ribeirao Preto, SP (Brazil)

    2009-10-30

    Lead (Pb) contamination in the black paper that recovers intraoral films (BKP) has been investigated. BKP samples were collected from the Radiology Clinics of the Dental School of Ribeirao Preto, University of Sao Paulo, Brazil. For sake of comparison, four different methods were used. The results revealed the presence of high lead levels, well above the maximum limit allowed by the legislation. Pb contamination levels achieved after the following treatments: paper digestion in nitric acid, microwave treatment, DIN38414-54 method and TCLP method were 997 {mu}g g{sup -1}, 189 {mu}g g{sup -1}, 20.8 {mu}g g{sup -1}, and 54.0 {mu}g g{sup -1}, respectively. Flame atomic absorption spectrometry (FAAS) and inductively coupled plasma mass spectrometry (ICP-MS) were employed for lead determination according to the protocols of the applied methods. Lead contamination in used BKP was confirmed by scanning electron microscopy coupled with energy dispersive X-ray microanalysis (SEM-EDS). All the SEM imaging was carried out in the secondary electron mode (SE) and backscattered-electron mode (QBSD) following punctual X-ray fluorescence spectra. Soil contamination derived from this product revealed the urgent need of addressing this problem. These elevated Pb levels, show that a preliminary treatment of BKP is mandatory before it is disposed into the common trash. The high lead content of this material makes its direct dumping into the environment unwise.

  2. First detection of lead in black paper from intraoral film

    International Nuclear Information System (INIS)

    Guedes, Debora F.C.; Silva, Reginaldo S.; Veiga, Marcia A.M.S. da; Pecora, Jesus D.

    2009-01-01

    Lead (Pb) contamination in the black paper that recovers intraoral films (BKP) has been investigated. BKP samples were collected from the Radiology Clinics of the Dental School of Ribeirao Preto, University of Sao Paulo, Brazil. For sake of comparison, four different methods were used. The results revealed the presence of high lead levels, well above the maximum limit allowed by the legislation. Pb contamination levels achieved after the following treatments: paper digestion in nitric acid, microwave treatment, DIN38414-54 method and TCLP method were 997 μg g -1 , 189 μg g -1 , 20.8 μg g -1 , and 54.0 μg g -1 , respectively. Flame atomic absorption spectrometry (FAAS) and inductively coupled plasma mass spectrometry (ICP-MS) were employed for lead determination according to the protocols of the applied methods. Lead contamination in used BKP was confirmed by scanning electron microscopy coupled with energy dispersive X-ray microanalysis (SEM-EDS). All the SEM imaging was carried out in the secondary electron mode (SE) and backscattered-electron mode (QBSD) following punctual X-ray fluorescence spectra. Soil contamination derived from this product revealed the urgent need of addressing this problem. These elevated Pb levels, show that a preliminary treatment of BKP is mandatory before it is disposed into the common trash. The high lead content of this material makes its direct dumping into the environment unwise.

  3. Melatonin reduces lead levels in blood, brain and bone and increases lead excretion in rats subjected to subacute lead treatment.

    Science.gov (United States)

    Hernández-Plata, Everardo; Quiroz-Compeán, Fátima; Ramírez-Garcia, Gonzalo; Barrientos, Eunice Yáñez; Rodríguez-Morales, Nadia M; Flores, Alberto; Wrobel, Katarzina; Wrobel, Kazimierz; Méndez, Isabel; Díaz-Muñoz, Mauricio; Robles, Juvencio; Martínez-Alfaro, Minerva

    2015-03-04

    Melatonin, a hormone known for its effects on free radical scavenging and antioxidant activity, can reduce lead toxicity in vivo and in vitro.We examined the effects of melatonin on lead bio-distribution. Rats were intraperitoneally injected with lead acetate (10, 15 or 20mg/kg/day) with or without melatonin (10mg/kg/day) daily for 10 days. In rats intoxicated with the highest lead doses, those treated with melatonin had lower lead levels in blood and higher levels in urine and feces than those treated with lead alone, suggesting that melatonin increases lead excretion. To explore the mechanism underlying this effect, we first assessed whether lead/melatonin complexes were formed directly. Electronic density functional (DFT) calculations showed that a lead/melatonin complex is energetically feasible; however, UV spectroscopy and NMR analysis showed no evidence of such complexes. Next, we examined the liver mRNA levels of metallothioneins (MT) 1 and 2. Melatonin cotreatment increased the MT2 mRNA expression in the liver of rats that received the highest doses of lead. The potential effects of MTs on the tissue distribution and excretion of lead are not well understood. This is the first report to suggest that melatonin directly affects lead levels in organisms exposed to subacute lead intoxication. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  4. Cost comparisons

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    How much does the LHC cost? And how much does this represent in other currencies? Below we present a table showing some comparisons with the cost of other projects. Looking at the figures, you will see that the cost of the LHC can be likened to that of three skyscrapers, or two seasons of Formula 1 racing! One year's budget of a single large F1 team is comparable to the entire materials cost of the ATLAS or CMS experiments.   Please note that all the figures are rounded for ease of reading.    CHF € $   LHC 4.6 billions 3 billions  4 billions   Space Shuttle Endeavour (NASA) 1.9 billion 1.3 billion 1.7 billion   Hubble Space Telescope (cost at launch – NASA/...

  5. Acute and chronic lead poisoning in cattle

    Energy Technology Data Exchange (ETDEWEB)

    Iosif, C

    1966-02-01

    Three cases of acute plumbism in cows are detailed: one of a six-year-old cow who accidentally ate about 100 gm. of lead (in 1956); the second of a 12-year-old cow who accidentally ate a packet containing about 100 gm. of lead used in painting; and the third of a three-week-old heifer who licked a freshly painted bucket. Route of exposure to lead can be gastrointestinal following deposition of lead fumes (lead oxide, sulfide, and sulfate) on pasturage and in exposed drinking water, or respiratory following the inhalation of such fumes. The presence of CO/sub 2/ in the respiratory tract is thought to provide a favorable situation for the dissolution of lead and the formation of soluble lead complexes. One author has calculated that 12% of respired lead is absorbed into the organism, while only 1-2% of ingested lead is absorbed.

  6. Lead-Binding Proteins: A Review

    Directory of Open Access Journals (Sweden)

    Harvey C. Gonick

    2011-01-01

    Full Text Available Lead-binding proteins are a series of low molecular weight proteins, analogous to metallothionein, which segregate lead in a nontoxic form in several organs (kidney, brain, lung, liver, erythrocyte. Whether the lead-binding proteins in every organ are identical or different remains to be determined. In the erythrocyte, delta-aminolevulinic acid dehydratase (ALAD isoforms have commanded the greatest attention as proteins and enzymes that are both inhibitable and inducible by lead. ALAD-2, although it binds lead to a greater degree than ALAD-1, appears to bind lead in a less toxic form. What may be of greater significance is that a low molecular weight lead-binding protein, approximately 10 kDa, appears in the erythrocyte once blood lead exceeds 39 μg/dL and eventually surpasses the lead-binding capacity of ALAD. In brain and kidney of environmentally exposed humans and animals, a cytoplasmic lead-binding protein has been identified as thymosin β4, a 5 kDa protein. In kidney, but not brain, another lead-binding protein has been identified as acyl-CoA binding protein, a 9 kDa protein. Each of these proteins, when coincubated with liver ALAD and titrated with lead, diminishes the inhibition of ALAD by lead, verifying their ability to segregate lead in a nontoxic form.

  7. Neurobehavioural effects of occupational exposure to lead.

    Science.gov (United States)

    Williamson, A M; Teo, R K

    1986-06-01

    A set of neurobehavioural tests selected on the basis of information processing theory was used to study the effect of low level occupational lead exposure on 59 lead workers compared with a matched control group of the same number. Only one of the lead exposed group had a blood lead concentration above the current threshold limit value of 3.81 mumol/l at the time of testing (mean 2.36 mumol/l, range 1.19-3.92 mumol/l) and none had been detected above that level in the previous three years. Nevertheless, most neurobehavioural functions tested showed some impairment in the lead workers. Visual sensory function was affected and, perhaps as a consequence, sustained attention and psychomotor tasks were performed more slowly by the lead exposed group. Cognitive functions were also impaired, with sensory store memory, short term memory, and learning abilities all showing deficits in lead workers. Such cognitive deficits may also be partly due to initial degradation of the visual input. Long term memory performance compared equally with control levels possibly because of development of a compensatory strategy such as rehearsal by the lead exposed subjects. Multiple linear regression analysis relating to lead workers test performance and their lead exposure showed that performance on the sensory store memory test alone was significantly related to exposure. This was probably due to the homogeneity of the lead exposed group with regard to blood lead concentrations and the use of blood lead as a measure of chronic lead exposure.

  8. Neurobehavioural effects of occupational exposure to lead

    Energy Technology Data Exchange (ETDEWEB)

    Williamson, A.M.; Teo, R.K.

    1986-06-01

    A set of neurobehavioural tests selected on the basis of information processing theory was used to study the effect of low level occupational lead exposure on 59 lead workers compared with a matched control group of the same number. Only one of the lead exposed group had a blood lead concentration above the current threshold limit value of 3.81 mumol/l at the time of testing (mean 2.36 mumol/l, range 1.19-3.92 mumol/l) and none had been detected above that level in the previous three years. Nevertheless, most neurobehavioural functions tested showed some impairment in the lead workers. Visual sensory function was affected and, perhaps as a consequence, sustained attention and psychomotor tasks were performed more slowly by the lead exposed group. Cognitive functions were also impaired, with sensory store memory, short term memory, and learning abilities all showing deficits in lead workers. Such cognitive deficits may also be partly due to initial degradation of the visual input. Long term memory performance compared equally with control levels possibly because of development of a compensatory strategy such as rehearsal by the lead exposed subjects. Multiple linear regression analysis relating to lead workers test performance and their lead exposure showed that performance on the sensory store memory test alone was significantly related to exposure. This was probably due to the homogeneity of the lead exposed group with regard to blood lead concentrations and the use of blood lead as a measure of chronic lead exposure.

  9. Isotopic Ligand Exchange of Some Hexa-Coordinated Inorganic Complexes with Halide Ions in Solution and in Crystals; Echanges Isotopiques de Coordinats de Complexes Inorganiques Hexacoordonnes Avec des Ions Halogenures en Solution et dans les Cristaux; Izotopnyj obmen ligand v nekotorykh geksakoordinirovannykh ne- organicheskikh kompleksakh s ionami galoidov v rastvore i kristallakh; Intercambio Isotopico de Ligandos de Complejos Inorganicos Hexacoordinados y Iones Haluro en Solucion y en Cristales

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, G. B. [Institut fuer Kernchemie der Universitaet Koeln, Cologne, Federal Republic of Germany (Germany)

    1965-10-15

    , the halide exchange of [OsCl{sub 6}]{sup 2-} and [Osl6]{sup 2-} was investigated in hydrochloric acid and hydroiodic acid, respectively, in methanolic acid and in ethanolic acid solution. The rates measured are compared with earlier results of the isotopic exchange of the corresponding hexabromo complex. Beside these investigations of the dissolved complexes, displacement reactions of labelled cis- and trans-[Co(en){sub 2}Cl*{sub 2}] Cl and trans- [Rh(en){sub 2}Cl*{sub 2}] Cl in the lattice were studied. The half-time of the exchange for both solid isomeric Co complexes is about 4 h at 150 Degree-Sign C. For the Rh complex a half-time of about 26 h was found at 225 Degree-Sign C. Activation energies of 30-35 kcal/mole were calculated. X-ray irradiation leads to an exchange increasing with the dose. In addition, the thermal exchange of irradiated crystals is accelerated. In contrast to the ethylenediamine complexes, the solid Rh and Ir pentamminebromo bromides or chlorides exchange only very slowly by raising the temperature even to 210 Degree-Sign C. But in these solid complexes ''activated'' exchange reactions take place if the complex receives excitation energy from a nuclear process such as the {sup 80m}Br -> {sup 80}Br isomeric transition. This phenomenon was investigated in some detail. (author) [French] La cinetique des echanges isotopiques donne des renseignements sur la labilite des complexes en solution et sur les mecanismes de substitution. L'echange des complexes [Rh(NH{sub 3}){sub 5}Br]{sup 2+} et [Ir(NH{sub 3}){sub 5}Br]{sup 2+}]{sup 2+} marques au {sup 82}Br avec des ions Br{sup -}, de trans- [Rh(en){sub 2}Cl{sub 2}]+ et de trans- [Co(en){sub 2}Cl{sub 2}]+ avec des ions Cl{sup -}, de trans- [Co(en){sub 2}Br{sub 2}]{sup +} avec des ions Br{sup -} et de [OsCl{sub 6}]{sup 2-} et [Osl{sub 6}]{sup 2-} avec des ions Cl{sup -} et I{sup -} respectivement a ete etudie en solution acide. Pour le complexe de pentamminebromo-iridium, l'echange est environ 60 fois

  10. Kinetics of oil saponification by lead salts in ancient preparations of pharmaceutical lead plasters and painting lead mediums.

    Science.gov (United States)

    Cotte, M; Checroun, E; Susini, J; Dumas, P; Tchoreloff, P; Besnard, M; Walter, Ph

    2006-12-15

    Lead soaps can be found in archaeological cosmetics as well as in oil paintings, as product of interactions of lead salts with oil. In this context, a better understanding of the formation of lead soaps allows a follow-up of the historical evolution of preparation recipes and provides new insights into conservation conditions. First, ancient recipes of both pharmaceutical lead plasters and painting lead mediums, mixtures of oil and lead salts, were reconstructed. The ester saponification by lead salts is determined by the preparation parameters which were quantified by FT-IR spectrometry. In particular, ATR/FT-IR spectrometer was calibrated by the standard addition method to quantitatively follow the kinetics of this reaction. The influence of different parameters such as temperature, presence of water and choice of lead salts was assessed: the saponification is clearly accelerated by water and heating. This analysis provides chemical explanations to the historical evolution of cosmetic and painting preparation recipes.

  11. Leading gravitational corrections and a unified universe

    DEFF Research Database (Denmark)

    Codello, Alessandro; Jain, Rajeev Kumar

    2016-01-01

    Leading order gravitational corrections to the Einstein-Hilbert action can lead to a consistent picture of the universe by unifying the epochs of inflation and dark energy in a single framework. While the leading local correction induces an inflationary phase in the early universe, the leading...... nonlocal term leads to an accelerated expansion of the universe at the present epoch. We argue that both the leading UV and IR terms can be obtained within the framework of a covariant effective field theory of gravity. The perturbative gravitational corrections therefore provide a fundamental basis...

  12. Exciton-relaxation dynamics in lead halides

    International Nuclear Information System (INIS)

    Iwanaga, Masanobu; Hayashi, Tetsusuke

    2003-01-01

    We survey recent comprehensive studies of exciton relaxation in the crystals of lead halides. The luminescence and electron-spin-resonance studies have revealed that excitons in lead bromide spontaneously dissociate and both electrons and holes get self-trapped individually. Similar relaxation has been also clarified in lead chloride. The electron-hole separation is ascribed to repulsive correlation via acoustic phonons. Besides, on the basis of the temperature profiles of self-trapped states, we discuss the origin of luminescence components which are mainly induced under one-photon excitation into the exciton band in lead fluoride, lead chloride, and lead bromide

  13. PSF interlaboratory comparison

    International Nuclear Information System (INIS)

    Kellogg, L.S.; Lippincott, E.P.

    1982-01-01

    Two experiments for interlaboratory verification of radiometric analysis methods have been conducted with dosimeters irradiated in the Oak Ridge Research Reactor (ORR) Poolside Facility (PSF) Surveillance Dosimeter Measurement Facility (SDMF). In a preliminary analysis of data supplied by the six participants, biases as large as 60% were observed which could lead to errors of this general magnitude in reported surveillance capsule fluence values. As a result of these comparisons, problems were identified and the spread in final values was greatly reduced. Relative agreement among the final results reported by four of the laboratories now appears to be satisfactory (the non-fission dosimeter results generally falling within +-5% and the fission dosimeter results within +-10%), but improvement is required in order to routinely meet Reactor Vessel Material Surveillance Program goals

  14. A multi-level model of blood lead as a function of air lead.

    Science.gov (United States)

    Richmond-Bryant, Jennifer; Meng, Qingyu; Davis, J Allen; Cohen, Jonathan; Svendsgaard, David; Brown, James S; Tuttle, Lauren; Hubbard, Heidi; Rice, Joann; Kirrane, Ellen; Vinikoor-Imler, Lisa; Kotchmar, Dennis; Hines, Erin; Ross, Mary

    2013-09-01

    National and local declines in lead (Pb) in blood (PbB) over the past several years coincide with the decline in ambient air Pb (PbA) concentrations. The objective of this work is to evaluate how the relationship between PbB levels and PbA levels has changed following the phase out of leaded gasoline and tightened controls on industrial Pb emissions over the past 30 years among a national population sample. Participant-level data from the National Health and Nutrition Examination Survey (NHANES) were employed for two time periods (1988-1994 and 1999-2008), and the model was corrected for housing, demographic, socioeconomic, and other covariates present in NHANES. NHANES data for PbB and covariates were merged with PbA data from the U.S. Environmental Protection Agency. Linear mixed effects models (LMEs) were run to assess the relationship of PbB with PbA; sample weights were omitted, given biases encountered with the use of sample weights in LMEs. The 1988-1994 age-stratified results found that ln(PbB) was statistically significantly associated with ln(PbA) for all age groups. The consistent influence of PbA on PbB across age groups for the years 1988-1994 suggests a ubiquitous exposure unrelated to age of the sample population. The comparison of effect estimates for ln(PbA) shows a statistically significant effect estimate and ANOVA results for ln(PbB) for the 6- to 11-year and 12- to 19-year age groups during 1999-2008. The more recent finding suggests that PbA has less consistent influence on PbB compared with other factors. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Ten Leading Causes of Death and Injury

    Science.gov (United States)

    ... Overdose Traumatic Brain Injury Violence Prevention Ten Leading Causes of Death and Injury Recommend on Facebook Tweet Share Compartir ... in Hospital Emergency Departments, United States – 2014 Leading Causes of Death Charts Causes of Death by Age Group 2016 [ ...

  16. A Public Health Approach to Addressing Lead

    Science.gov (United States)

    Describes EPA’s achievements in reducing childhood lead exposures and emphasizes the need to continue actions to further reduce lead exposures, especially in those communities where exposures remain high.

  17. Lead Intoxication in Children in Birmingham

    Science.gov (United States)

    Betts, P. R.; Astley, R.; Raine, D. N.

    1973-01-01

    Of 38 children investigated between 1966 and 1971 who had a blood lead concentration greater than 37 μg/100 ml eight had encephalopathy and one died; all these eight had a blood lead concentration of 99 μg/100 ml or above. Blood lead levels are related to haemoglobin concentrations and anaemia is common in children with blood lead concentrations of 37-60 μg/100 ml, levels previously accepted as harmless. Children with blood lead concentrations greater than 60 μg/100 ml show radiological evidence of lead intoxication, and treatment for this should be considered when blood lead concentration exceeds 37 μg/100 ml. Children presenting with unexplained encephalopathy should be radiographed for evidence of lead intoxication. ImagesFIG. 2FIG. 1 PMID:4691065

  18. Lead's Impact on Indoor Air Quality

    Science.gov (United States)

    Lead has long been recognized as a harmful environmental pollutant. There are many ways in which humans are exposed to lead: through air, drinking water, food, contaminated soil, deteriorating paint, and dust.

  19. Leading particle in deep inelastic scattering

    International Nuclear Information System (INIS)

    Petrov, V.A.

    1984-01-01

    The leading particle effect in deep inelastic scattering is considered. The change of the characteris cs shape of the leading particle inclusive spectrum with Q 2 is estimated to be rather significant at very high Q 2

  20. Neutron Physics aspects of using lead as a coolant in Fast Reactors

    International Nuclear Information System (INIS)

    Kiefhaber, E.

    1991-02-01

    The use of lead as a coolant for fast reactors is being considered as an attractive alternative in the USSR, especially with respect to its inherent safety features. In order to come to an own assessment at KfK, some investigations have been performed concerning a comparison of the nuclear characteristics of fast reactors with lead and sodium cooling. The studies have shown, that the nuclear and thermal hydraulic design calculations do not face special problems and that the nuclear characteristics of both types of cores do not differ essentially, except for the coolant density or void effect, which is more favourable for smaller sized lead cooled cores. A proper safety assessment of lead cooled cores will however require more detailed safety studies. Crucial points of lead cooling are the strong corrosion of austenitic steels in lead and the unknown behavior of ferritic steels in lead and under irradiation

  1. Dosimetry of small electron fields shaped by lead

    International Nuclear Information System (INIS)

    Perez, M.; Hill, R.; Whitaker, M.; Greig, L.; West, M.; Jones, L.

    2000-01-01

    Full text: Electron fields can be used to treat superficial cancers. Field shaping can be achieved by placing lead on the patient surface to minimise the dose to surrounding areas and may improve beam penumbra compared to using standard applicators. However, significant dosimetry changes under high density material edges for electron fields have been reported (W Pohlit and KH Manegold, cited in The Physics of Radiation Therapy, P.M. Khan, 1994). This project evaluated the dosimetry of small dimension electron fields shaped with lead placed on the surface. Comparisons were made between circular lead cutouts (3 and 5cm diameters) and an open electron applicator (5cm diameter). For each of these fields depth doses and profiles were measured using a diode detector in a water phantom, and isodoses were measured using X-Omat film sandwiched within a Solid water phantom. Output factors were measured in the Solid water using a Markus parallel plate ionisation chamber. The effect of the lead thickness on the profiles and output was quantified and the thickness used for the final measurements selected so as to give less than 5% transmission of the primary dose. Penumbral widths for 6MeV and 8MeV using the lead cutouts showed distinct differences compared with the open applicator. At depths of the 90% relative dose the profiles for lead shaped fields showed tighter penumbra widths by an average of 2 mm. This became more pronounced nearer the surface where, at 2mm depth, the difference in penumbral widths was an average of 4mm. The 3cm lead cutouts showed surface dose increases of 6% and 9% for 6MeV and 8 MeV respectively. Depth dose parameters (D max and R 90 ) varied by no more than 2mm between the lead cutouts and the open applicator measurements. Lead can be used to shape electron fields for radiotherapy treatments. Depth dose characteristics do not vary significantly with a 5 cm circular applicator. The penumbral width indicates less isodose spread for the lead cutout

  2. Lead contamination of inexpensive plastic jewelry

    Energy Technology Data Exchange (ETDEWEB)

    Yost, Jamie L. [Department of Chemistry, Ashland University, Ashland, Ohio (United States); Weidenhamer, Jeffrey D. [Department of Chemistry, Ashland University, Ashland, Ohio (United States)], E-mail: jweiden@ashland.edu

    2008-04-15

    The neurological hazards of lead to children are well-known. As a result of recent documented cases of lead poisoning, regulatory attention in the United States has focused on the lead content of children's metal jewelry. By contrast, little is known about the possible hazards of plastic jewelry items. The objective of this study was to determine whether inexpensive plastic jewelry is a possible source of toxic lead for children. Samples of more than 100 inexpensive plastic jewelry items were analyzed for lead content. Beads were screened by soaking in 1 M nitric acid. Nine items found to release more than 30 {mu}g of lead per bead were further tested for accessible lead, and scrapings of the bead coatings were analyzed for total lead content. The maximum accessible lead found was 49 {mu}g per bead, which is below the current US Consumer Product Safety Commission limit of 175 {mu}g. However, when the number of beads in each item was taken into account, six of the nine leaded samples contained more than 175 {mu}g accessible lead per item. The lead in these items appears to be associated with lead-based paints used to produce glossy coatings on imitation pearls and similar items. Coatings obtained by scraping individual beads contained 3.5-23% lead, which far exceeds the US regulatory limit of 0.06% lead in paints on items intended for children. Our results demonstrate that plastic jewelry items merit the attention of public health and consumer protection agencies seeking to limit the exposure of children to lead.

  3. Lead exposure from aluminum cookware in Cameroon

    International Nuclear Information System (INIS)

    Weidenhamer, Jeffrey D.; Kobunski, Peter A.; Kuepouo, Gilbert; Corbin, Rebecca W.; Gottesfeld, Perry

    2014-01-01

    Blood lead levels have decreased following the removal of lead from gasoline in most of the world. However, numerous recent studies provide evidence that elevated blood lead levels persist in many low and middle-income countries around the world at much higher prevalence than in the more developed countries. One potential source of lead exposure that has not been widely investigated is the leaching of lead from artisanal aluminum cookware, which is commonly used in the developing world. Twenty-nine samples of aluminum cookware and utensils manufactured by local artisans in Cameroon were collected and analyzed for their potential to release lead during cooking. Source materials for this cookware included scrap metal such as engine parts, radiators, cans, and construction materials. The lead content of this cookware is relatively low (< 1000 ppm by X-ray fluorescence), however significant amounts of lead, as well as aluminum and cadmium were released from many of the samples using dilute acetic acid extractions at boiling and ambient temperatures. Potential exposures to lead per serving were estimated to be as high as 260 μg, indicating that such cookware can pose a serious health hazard. We conclude that lead, aluminum and cadmium can migrate from this aluminum cookware during cooking and enter food at levels exceeding recommended public health guidelines. Our results support the need to regulate lead content of materials used to manufacture these pots. Artisanal aluminum cookware may be a major contributor to lead poisoning throughout the developing world. Testing of aluminum cookware in other developing countries is warranted. - Highlights: • Cookware is manufactured in Cameroon from scrap aluminum including car parts. • Twenty-nine cookware samples were evaluated for their potential to leach lead. • Boiling extractions to simulate the effects of cooking released significant lead. • Potential lead exposures per serving are estimated as high as 260 μg.

  4. Lead exposure from aluminum cookware in Cameroon

    Energy Technology Data Exchange (ETDEWEB)

    Weidenhamer, Jeffrey D.; Kobunski, Peter A. [Department of Chemistry, Geology and Physics, 401 College Ave., Ashland University, Ashland, OH 44805 (United States); Kuepouo, Gilbert [Research and Education Centre for Development (CREPD), Yaounde (Cameroon); Corbin, Rebecca W. [Department of Chemistry, Geology and Physics, 401 College Ave., Ashland University, Ashland, OH 44805 (United States); Gottesfeld, Perry, E-mail: pgottesfeld@okinternational.org [Occupational Knowledge International, San Francisco, CA (United States)

    2014-10-15

    Blood lead levels have decreased following the removal of lead from gasoline in most of the world. However, numerous recent studies provide evidence that elevated blood lead levels persist in many low and middle-income countries around the world at much higher prevalence than in the more developed countries. One potential source of lead exposure that has not been widely investigated is the leaching of lead from artisanal aluminum cookware, which is commonly used in the developing world. Twenty-nine samples of aluminum cookware and utensils manufactured by local artisans in Cameroon were collected and analyzed for their potential to release lead during cooking. Source materials for this cookware included scrap metal such as engine parts, radiators, cans, and construction materials. The lead content of this cookware is relatively low (< 1000 ppm by X-ray fluorescence), however significant amounts of lead, as well as aluminum and cadmium were released from many of the samples using dilute acetic acid extractions at boiling and ambient temperatures. Potential exposures to lead per serving were estimated to be as high as 260 μg, indicating that such cookware can pose a serious health hazard. We conclude that lead, aluminum and cadmium can migrate from this aluminum cookware during cooking and enter food at levels exceeding recommended public health guidelines. Our results support the need to regulate lead content of materials used to manufacture these pots. Artisanal aluminum cookware may be a major contributor to lead poisoning throughout the developing world. Testing of aluminum cookware in other developing countries is warranted. - Highlights: • Cookware is manufactured in Cameroon from scrap aluminum including car parts. • Twenty-nine cookware samples were evaluated for their potential to leach lead. • Boiling extractions to simulate the effects of cooking released significant lead. • Potential lead exposures per serving are estimated as high as 260 μg.

  5. Lead contamination of inexpensive plastic jewelry

    International Nuclear Information System (INIS)

    Yost, Jamie L.; Weidenhamer, Jeffrey D.

    2008-01-01

    The neurological hazards of lead to children are well-known. As a result of recent documented cases of lead poisoning, regulatory attention in the United States has focused on the lead content of children's metal jewelry. By contrast, little is known about the possible hazards of plastic jewelry items. The objective of this study was to determine whether inexpensive plastic jewelry is a possible source of toxic lead for children. Samples of more than 100 inexpensive plastic jewelry items were analyzed for lead content. Beads were screened by soaking in 1 M nitric acid. Nine items found to release more than 30 μg of lead per bead were further tested for accessible lead, and scrapings of the bead coatings were analyzed for total lead content. The maximum accessible lead found was 49 μg per bead, which is below the current US Consumer Product Safety Commission limit of 175 μg. However, when the number of beads in each item was taken into account, six of the nine leaded samples contained more than 175 μg accessible lead per item. The lead in these items appears to be associated with lead-based paints used to produce glossy coatings on imitation pearls and similar items. Coatings obtained by scraping individual beads contained 3.5-23% lead, which far exceeds the US regulatory limit of 0.06% lead in paints on items intended for children. Our results demonstrate that plastic jewelry items merit the attention of public health and consumer protection agencies seeking to limit the exposure of children to lead

  6. Severe Neurotoxicity Following Ingestion of Tetraethyl Lead

    OpenAIRE

    Wills, Brandon K.; Christensen, Jason; Mazzoncini, Joe; Miller, Michael

    2010-01-01

    Organic lead compounds are potent neurotoxins which can result in death even from small exposures. Traditionally, these compounds are found in fuel stabilizers, anti-knock agents, and leaded gasoline. Cases of acute organic lead intoxication have not been reported for several decades. We report a case of a 13-year-old Iraqi male who unintentionally ingested a fuel stabilizer containing 80–90% tetraethyl lead, managed at our combat support hospital. The patient developed severe neurologic symp...

  7. 40 CFR 1508.16 - Lead agency.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Lead agency. 1508.16 Section 1508.16 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY TERMINOLOGY AND INDEX § 1508.16 Lead agency. Lead agency means the agency or agencies preparing or having taken primary responsibility for preparing the...

  8. Is Your Child Safe from Lead Poisoning?

    Centers for Disease Control (CDC) Podcasts

    2008-10-02

    In this podcast, Dr. Mary Jean Brown, chief of CDC's Lead Poisoning and Prevention Program, discusses the importance of testing children for lead poisoning, who should be tested, and what parents can do to prevent lead poisoning.  Created: 10/2/2008 by National Center for Environmental Health (NCEH).   Date Released: 10/2/2008.

  9. Significance of Lead Residues in Mallard Tissues

    Science.gov (United States)

    Longcore, J.R.; Locke, L.N.; Bagley, George E.; Andrews, R.

    1974-01-01

    Tissues of adult, lead-dosed mallards that either died or were sacrificed were analyzed for lead. Lead levels in brains, tibiae, and breast muscle of ducks that died and in tibiae of ducks that were sacrificed increased significantly from dosage until death. Lead in the heart, lung, and blood from sacrificed ducks decreased significantly from dosage until death. Lead concentrations in tissues from ducks in the two groups were not significantly different except for the liver, kidney, and lung. Average lead levels in the livers and kidneys of ducks that died were significantly higher than those in ducks that were sacrificed. The mean concentration of lead in the lungs of the ducks sacrificed was significantly higher than the mean level in the lungs of ducks that died. Measurements of the lead concentrations in this study, when compared with lead levels reported in the literature for avian and non-avian species, showed that arbitrary diagnostic levels indicating lead poisoning could be set. In mallard ducks, lead levels exceeding 3 ppm in the brain, 6 to 20 ppm in the kidney or liver, or 10 ppm in clotted blood from the heart indicated acute exposure to lead.

  10. Early Reading Proficiency. Leading Indicator Spotlight

    Science.gov (United States)

    Musen, Lindsey

    2010-01-01

    In "Beyond Test Scores: Leading Indicators for Education," Foley and colleagues (2008) define leading indicators as those that "provide early signals of progress toward academic achievement" (p. 1) and stress that educators "need leading indicators to help them see the direction their efforts are going in and to take…

  11. Radioactive lead studies in the human

    International Nuclear Information System (INIS)

    Blake, K.C.H.

    1980-08-01

    The differing susceptibility of individuals to the toxic effects of chronic lead exposure has never been fully understood. As the major intake of lead in the human is from food and beverages, any variation between individuals of the quantity of lead absorbed from the gut, and of the distribution and excretion of this lead, may account for the differences in individual susceptibility. The food and beverages themselves may have an influence, and to investigate their effects on absorption, distribution and excretion of lead, experiments were performed on normal subjects using a short lived radionuclide of lead, 203 Pb, and instruments generally available in Nuclear Medicine. Lead absorption between different individuals showed a wide variation when 203 Pb was taken as a single dose between meals. Minerals were found to be mainly responsible for affecting absorption when one subject ingested 203 Pb in control meals from which one dietary constituent at a time was omitted. Calcium and phosphorous were found to reduce the absorption of 203 Pb to approximately the same level as that produced by the total minerals. Calcium reduced absorption more than phosphorous when these minerals were ingested separately with 203 Pb. It was concluded that the calcium and phosphorous in the diet could influence susceptibility to lead toxicity through changes in the absorption of food and water lead and in the distribution of lead in the body. The results suggest that the prophylactic effect of calcium on lead absorption should be recognised and applied in this time of increased environmental levels of lead

  12. Eryptosis in lead-exposed workers

    International Nuclear Information System (INIS)

    Aguilar-Dorado, Itzel-Citlalli; Hernández, Gerardo; Quintanar-Escorza, Martha-Angelica; Maldonado-Vega, María; Rosas-Flores, Margarita; Calderón-Salinas, José-Víctor

    2014-01-01

    Eryptosis is a physiological phenomenon in which old and damaged erythrocytes are removed from circulation. Erythrocytes incubated with lead have exhibited major eryptosis. In the present work we found evidence of high levels of eryptosis in lead exposed workers possibly via oxidation. Blood samples were taken from 40 male workers exposed to lead (mean blood lead concentration 64.8 μg/dl) and non-exposed workers (4.2 μg/dl). The exposure to lead produced an intoxication characterized by 88.3% less δ-aminolevulinic acid dehydratase (δALAD) activity in lead exposed workers with respect to non-lead exposed workers. An increment of oxidation in lead exposed workers was characterized by 2.4 times higher thiobarbituric acid-reactive substance (TBARS) concentration and 32.8% lower reduced/oxidized glutathione (GSH/GSSG) ratio. Oxidative stress in erythrocytes of lead exposed workers is expressed in 192% higher free calcium concentration [Ca 2+ ] i and 1.6 times higher μ-calpain activity with respect to non-lead exposed workers. The adenosine triphosphate (ATP) concentration was not significantly different between the two worker groups. No externalization of phosphatidylserine (PS) was found in non-lead exposed workers (< 0.1%), but lead exposed workers showed 2.82% externalization. Lead intoxication induces eryptosis possibly through a molecular pathway that includes oxidation, depletion of reduced glutathione (GSH), increment of [Ca 2+ ], μ-calpain activation and externalization of PS in erythrocytes. Identifying molecular signals that induce eryptosis in lead intoxication is necessary to understand its physiopathology and chronic complications. - Graphical abstract: Fig. 1. (A) Blood lead concentration (PbB) and (B) phosphatidylserine externalization on erythrocyte membranes of non-lead exposed (□) and lead exposed workers (■). Values are mean ± SD. *Significantly different (P < 0.001). - Highlights: • Erythrocytes of lead exposed workers showed higher PS

  13. Eryptosis in lead-exposed workers

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar-Dorado, Itzel-Citlalli [Biochemistry Department, Centro de Investigación y Estudios Avanzados IPN, México, DF (Mexico); Hernández, Gerardo [Section of Methodology of Science, Centro de Investigación y Estudios Avanzados IPN, México, DF (Mexico); Quintanar-Escorza, Martha-Angelica [Faculty of Medicine, UJED, Durango, DGO (Mexico); Maldonado-Vega, María [CIATEC, León, GTO (Mexico); Rosas-Flores, Margarita [Biochemistry Department, Centro de Investigación y Estudios Avanzados IPN, México, DF (Mexico); Calderón-Salinas, José-Víctor, E-mail: jcalder@cinvestav.mx [Biochemistry Department, Centro de Investigación y Estudios Avanzados IPN, México, DF (Mexico)

    2014-12-01

    Eryptosis is a physiological phenomenon in which old and damaged erythrocytes are removed from circulation. Erythrocytes incubated with lead have exhibited major eryptosis. In the present work we found evidence of high levels of eryptosis in lead exposed workers possibly via oxidation. Blood samples were taken from 40 male workers exposed to lead (mean blood lead concentration 64.8 μg/dl) and non-exposed workers (4.2 μg/dl). The exposure to lead produced an intoxication characterized by 88.3% less δ-aminolevulinic acid dehydratase (δALAD) activity in lead exposed workers with respect to non-lead exposed workers. An increment of oxidation in lead exposed workers was characterized by 2.4 times higher thiobarbituric acid-reactive substance (TBARS) concentration and 32.8% lower reduced/oxidized glutathione (GSH/GSSG) ratio. Oxidative stress in erythrocytes of lead exposed workers is expressed in 192% higher free calcium concentration [Ca{sup 2+}]{sub i} and 1.6 times higher μ-calpain activity with respect to non-lead exposed workers. The adenosine triphosphate (ATP) concentration was not significantly different between the two worker groups. No externalization of phosphatidylserine (PS) was found in non-lead exposed workers (< 0.1%), but lead exposed workers showed 2.82% externalization. Lead intoxication induces eryptosis possibly through a molecular pathway that includes oxidation, depletion of reduced glutathione (GSH), increment of [Ca{sup 2+}], μ-calpain activation and externalization of PS in erythrocytes. Identifying molecular signals that induce eryptosis in lead intoxication is necessary to understand its physiopathology and chronic complications. - Graphical abstract: Fig. 1. (A) Blood lead concentration (PbB) and (B) phosphatidylserine externalization on erythrocyte membranes of non-lead exposed (□) and lead exposed workers (■). Values are mean ± SD. *Significantly different (P < 0.001). - Highlights: • Erythrocytes of lead exposed workers

  14. A green lead hydrometallurgical process based on a hydrogen-lead oxide fuel cell.

    Science.gov (United States)

    Pan, Junqing; Sun, Yanzhi; Li, Wei; Knight, James; Manthiram, Arumugam

    2013-01-01

    The automobile industry consumed 9 million metric tons of lead in 2012 for lead-acid batteries. Recycling lead from spent lead-acid batteries is not only related to the sustainable development of the lead industry, but also to the reduction of lead pollution in the environment. The existing lead pyrometallurgical processes have two main issues, toxic lead emission into the environment and high energy consumption; the developing hydrometallurgical processes have the disadvantages of high electricity consumption, use of toxic chemicals and severe corrosion of metallic components. Here we demonstrate a new green hydrometallurgical process to recover lead based on a hydrogen-lead oxide fuel cell. High-purity lead, along with electricity, is produced with only water as the by-product. It has a >99.5% lead yield, which is higher than that of the existing pyrometallurgical processes (95-97%). This greatly reduces lead pollution to the environment.

  15. Measurement Of Lead Equivalent Thickness For Irradiation Room: An Analysis

    International Nuclear Information System (INIS)

    Mohd Khalid Matori; Azuhar Ripin; Husaini Salleh; Mohd Khairusalih Mohd Zin; Muhammad Jamal Muhd Isa; Mohd Faizal Abdul Rahman

    2014-01-01

    The Malaysian Ministry of Health (MOH) has established that the irradiation room must have a sufficient thickness of shielding to ensure that requirements for the purpose of radiation protection of patients, employees and the public are met. This paper presents a technique using americium-241 source to test and verify the integrity of the shielding thickness in term of lead equivalent for irradiation room at health clinics own by MOH. Results of measurement of 8 irradiation rooms conducted in 2014 were analyzed for this presentation. Technical comparison of the attenuation of gamma rays from Am-241 source through the walls of the irradiation room and pieces of lead were used to assess the lead equivalent thickness of the walls. Results showed that almost all the irradiation rooms tested meet the requirements of the Ministry of Health and is suitable for the installation of the intended diagnostic X-ray apparatus. Some specific positions such as door knobs and locks, electrical plug sockets were identified with potential to not met the required lead equivalent thickness hence may contribute to higher radiation exposure to workers and the public. (author)

  16. Increased bone calcium dissociation in lead-exposed rats

    Directory of Open Access Journals (Sweden)

    Eko Suhartono

    2012-12-01

    Full Text Available Background Lead is still a major environmental and occupational health hazard, since it is extensively used in the production of paints, gasoline and cosmetics. This causes the metal to be ubiquitous in the environment, being found in the air, soil, and water, from which it can enter the human body by inhalation or ingestion. Absorbed lead is capable of altering the calcium levels in bone. The aim of this study was to demonstrate the effect of lead on bone calcium levels by measuring the reaction constant, Gibbs free energy, and enthalpy. Methods This study was of pure experimental design using 100 male albino rats (Rattus norvegicus. The experimental animals were assigned by simple randomization to two groups, one group receiving lead acetate orally at a dosage of 100 mg/kgBW, while the other group did not receive lead acetate. The intervention was given for 4 weeks and the rats were observed weekly for measurement of bone calcium levels by the permanganometric method. Results This study found that k1 (hydroxyapatite dissociation rate constant was 0.90 x 10-3 dt-1, and that k2 (hydroxyapatite association rate constant was 6.16 x 10-3 dt-1 for the control group, whereas for the intervention group k1 = 26.20 x 10-3 dt-1 and k2 = 16.75 x 10-3 dt-1. Thermodynamically, the overall reaction was endergonic and endothermic (DG > 0 and DH > 0. ConclusionS Lead exposure results in increased dissociation rate of bone in comparison with its association rate. Overall, the reaction was endergonic and endothermic (DG > 0 and DH > 0.

  17. Increased bone calcium dissociation in lead-exposed rats

    Directory of Open Access Journals (Sweden)

    Eko Suhartono

    2015-12-01

    Full Text Available BACKGROUND Lead is still a major environmental and occupational health hazard, since it is extensively used in the production of paints, gasoline and cosmetics. This causes the metal to be ubiquitous in the environment, being found in the air, soil, and water, from which it can enter the human body by inhalation or ingestion. Absorbed lead is capable of altering the calcium levels in bone. The aim of this study was to demonstrate the effect of lead on bone calcium levels by measuring the reaction constant, Gibbs free energy, and enthalpy. METHODS This study was of pure experimental design using 100 male albino rats (Rattus norvegicus. The experimental animals were assigned by simple randomization to two groups, one group receiving lead acetate orally at a dosage of 100 mg/ kgBW, while the other group did not receive lead acetate. The intervention was given for 4 weeks and the rats were observed weekly for measurement of bone calcium levels by the permanganometric method. RESULTS This study found that k1 (hydroxyapatite dissociation rate constant was 0.90 x 10-3 dt-1, and that k2 (hydroxyapatite association rate constant was 6.16 x 10-3 dt-1 for the control group, whereas for the intervention group k1 = 26.20 x 10-3 dt-1 and k2 = 16.75 x 10-3 dt-1. Thermodynamically, the overall reaction was endergonic and endothermic (ΔG > 0 and ΔH > 0. CONCLUSIONS Lead exposure results in increased dissociation rate of bone in comparison with its association rate. Overall, the reaction was endergonic and endothermic (ΔG > 0 and ΔH > 0.

  18. [Effect of lead on the cardiovascular system].

    Science.gov (United States)

    Zyśko, Dorota; Chlebda, Ewa; Gajek, Jacek

    2004-11-01

    Lead is a metal widely spread in the natural environment. It is strongly toxic, particularly to the peripheral and central nervous systems. The toxic influence on the cardiovascular system is most pronounced in case of higher exposures, where myocardium and the renal circulation are affected, in consequence of which secondary arterial hypertension can develop. It seems that lead affects the cardiovascular system mainly by changing the peripheral autonomic nervous system and leading to chronic neuropathy. Chronic exposure, even to low doses of lead, can impair conduction in myocardium. In order to assess those changes thoroughly prospective studies involving newly employed workers with occupational exposure to toxic activity of lead will be necessary.

  19. High-temperature superconducting current leads

    Science.gov (United States)

    Hull, J. R.

    1992-07-01

    The use of high-temperature superconductors (HTSs) for current leads to deliver power to devices at liquid helium temperature is near commercial realization. The use of HTSs in this application has the potential to reduce refrigeration requirements and helium boiloff to values significantly lower than the theoretical best achievable with conventional leads. Considerable advantage is achieved by operating these leads with an intermediate temperature heat sink. The HTS part of the lead can be made from pressed and sintered powder. Powder-in-tube fabrication is also possible, however, the normal metal part of the lead acts as a thermal short and cannot provide much stabilization without increasing the refrigeration required. Lead stability favors designs with low current density. Such leads can be manufactured with today's technology, and lower refrigeration results from the same allowable burnout time. Higher current densities result in lower boiloff for the same lead length, but bumout times can be very short. In comparing experiment to theory, the density of helium vapor needs to be accounted for in calculating the expected boiloff. For very low-loss leads, two-dimensional heat transfer and the state of the dewar near the leads may play a dominant role in lead performance.

  20. Superconducting lead particles produced by chemical techniques

    Science.gov (United States)

    Fariss, T. L.; Nixon, W. E.; Bucelot, T. J.; Deaver, B. S., Jr.; Mitchell, J. W.

    1982-09-01

    The superconductivity of extremely small lead particles has been studied as a function of size, surface condition, and connectivity using chemical techniques to produce particles of well-controlled size and shape suspended in insulating media. Approximately monodisperse suspensions of equiaxed, rod, and lath-shaped particles of lead halides and other lead compounds suspended in gelatin, polyacrylamide, polyvinylpyrrolidone, polyvinyl alcohol, methyl cellulose, and hydroxyethyl cellulose have been produced. These particles have been reduced to pseudomorphs of lead in the liquid phase or the suspensions have been coated on substrates and dried before reduction. Reducing solutions containing aminoiminomethanesulfinic acid are effective with particles of lead halides, lead phosphate, lead sulfate, and lead tartrate. Suspensions of smaller discrete lead particles have also been produced by direct reduction of solutions of soluble lead salts containing suitable polymers, chelating, and stabilizing agents. Dispersions with mean particle dimensions between 3 nm and 5 μm, and a narrow size-frequency distribution, have been produced. The superconductivity of the particles has been characterized by measurements of the magnetization as a function of temperature and magnetic field. The larger particles have a transition temperature of 7.2 K, the same as bulk lead; however, for particles of characteristic dimensions less than 20 nm, the transition temperature is lower by ˜0.1 K.

  1. Superconducting lead particles produced by chemical techniques

    International Nuclear Information System (INIS)

    Fariss, T.L.; Nixon, W.E.; Bucelot, T.J.; Deaver, B.S. Jr.; Mitchell, J.W.

    1982-01-01

    The superconductivity of extremely small lead particles has been studied as a function of size, surface condition, and connectivity using chemical techniques to produce particles of well-controlled size and shape suspended in insulating media. Approximately monodisperse suspensions of equiaxed, rod, and lath-shaped particles of lead halides and other lead compounds suspended in gelatin, polyacrylamide, polyvinylpyrrolidone, polyvinyl alcohol, methyl cellulose, and hydroxyethyl cellulose have been produced. These particles have been reduced to pseudomorphs of lead in the liquid phase or the suspensions have been coated on substrates and dried before reduction. Reducing solutions containing aminoiminomethanesulfinic acid are effective with particles of lead halides, lead phosphate, lead sulfate, and lead tartrate. Suspensions of smaller discrete lead particles have also been produced by direct reduction of solutions of soluble lead salts containing suitable polymers, chelating, and stabilizing agents. Dispersions with mean particle dimensions between 3 nm and 5 μm, and a narrow size-frequency distribution, have been produced. The superconductivity of the particles has been characterized by measurements of the magnetization as a function of temperature and magnetic field. The larger particles have a transition temperature of 7.2 K, the same as bulk lead; however, for particles of characteristic dimensions less than 20 nm, the transition temperature is lower by approx.0.1 K

  2. Editorial: Lead Risk Assessment and Health Effects

    Directory of Open Access Journals (Sweden)

    Howard W. Mielke

    2016-06-01

    Full Text Available In 1980, Clair C. Patterson stated: “Sometime in the near future it probably will be shown that the older urban areas of the United States have been rendered more or less uninhabitable by the millions of tons of poisonous industrial lead residues that have accumulated in cities during the past century”. We live in the near future about which this quote expressed concern. This special volume of 19 papers explores the status of scientific evidence regarding Dr. Patterson’s statement on the habitability of the environments of communities. Authors from 10 countries describe a variety of lead issues in the context of large and small communities, smelter sites, lead industries, lead-based painted houses, and vehicle fuel treated with lead additives dispersed by traffic. These articles represent the microcosm of the larger health issues associated with lead. The challenges of lead risk require a concerted global action for primary prevention.

  3. Update on Recovering Lead From Scrap Batteries

    Science.gov (United States)

    Cole, E. R.; Lee, A. Y.; Paulson, D. L.

    1985-02-01

    Previous work at the Bureau of Mines Rolla Research Center, U.S. Department of the Interior, resulted in successful development of a bench-scale, combination electrorefining-electrowinning method for recycling lead from scrap batteries by using waste fluosilicic acid (H2SiF6) as electrolyte.1,2 This paper describes larger scale experiments. Prior attempts to electrowin lead failed because large quantities of insoluble lead dioxide were deposited on the anodes at the expense of lead deposition on the cathodes. A major breakthrough was achieved with the discovery that lead dioxide formation at the anodes is prevented by adding a small amount of phosphorus to the electrolyte. The amount of PbO2 formed on the anodes during lead electrowinning was less than 1% of the total lead deposited on the cathodes. This work recently won the prestigious IR·100 award as one of the 100 most significant technological advances of 1984.

  4. Isotopic analysis of bullet lead samples

    International Nuclear Information System (INIS)

    Sankar Das, M.; Venkatasubramanian, V.S.; Sreenivas, K.

    1976-01-01

    The possibility of using the isotopic composition of lead for the identification of bullet lead is investigated. Lead from several spent bullets were converted to lead sulphide and analysed for the isotopic abundances using an MS-7 mass spectrometer. The abundances are measured relative to that for Pb 204 was too small to permit differentiation, while the range of variation of Pb 206 and Pb 207 and the better precision in their analyses permitted differentiating samples from one another. The correlation among the samples examined has been pointed out. The method is complementary to characterisation of bullet leads by the trace element composition. The possibility of using isotopically enriched lead for tagging bullet lead is pointed out. (author)

  5. Lead sources in human diet in Greenland

    DEFF Research Database (Denmark)

    Bjerregaard, Peter; Johansen, Poul; Mulvad, Gert

    2004-01-01

    Although blood lead levels have declined in Greenland, they are still elevated despite the fact that lead levels in the Greenland environment are very low. Fragments of lead shot in game birds have been suggested as an important source of dietary exposure, and meals of sea birds, particularly eider......, contain high concentrations of lead. In a cross-sectional population survey in Greenland in 1993-1994, blood lead adjusted for age and sex was found to be associated with the reported consumption of sea birds. Participants reporting less than weekly intake of sea birds had blood lead concentrations...... of approximately 75 microg/L, whereas those who reported eating sea birds several times a week had concentrations of approximately 110 microg/L, and those who reported daily intake had concentrations of 170 microg/L (p = 0.01). Blood lead was not associated with dietary exposure to other local or imported food...

  6. The technical and economic efficiency in the mineral processing for lead-zinc and copper ores by Microsoft excel

    OpenAIRE

    Krstev, Aleksandar; Krstev, Boris; Krstev, Dejan; Vuckovski, Zoran

    2012-01-01

    The comparisons between economical and technical efficiency for lead flotation indicators, zinc flotation indicators in Sasa mine, Toranica and Zletovo mine. The comparisons for economic and technical efficiency for copper flotation indicators in Bucim mine. The possibility of equaled between both efficiencies for flotation indicators from mentioned mines using Microsoft Excel 2010.

  7. Eryptosis in lead-exposed workers.

    Science.gov (United States)

    Aguilar-Dorado, Itzel-Citlalli; Hernández, Gerardo; Quintanar-Escorza, Martha-Angelica; Maldonado-Vega, María; Rosas-Flores, Margarita; Calderón-Salinas, José-Víctor

    2014-12-01

    Eryptosis is a physiological phenomenon in which old and damaged erythrocytes are removed from circulation. Erythrocytes incubated with lead have exhibited major eryptosis. In the present work we found evidence of high levels of eryptosis in lead exposed workers possibly via oxidation. Blood samples were taken from 40 male workers exposed to lead (mean blood lead concentration 64.8μg/dl) and non-exposed workers (4.2μg/dl). The exposure to lead produced an intoxication characterized by 88.3% less δ-aminolevulinic acid dehydratase (δALAD) activity in lead exposed workers with respect to non-lead exposed workers. An increment of oxidation in lead exposed workers was characterized by 2.4 times higher thiobarbituric acid-reactive substance (TBARS) concentration and 32.8% lower reduced/oxidized glutathione (GSH/GSSG) ratio. Oxidative stress in erythrocytes of lead exposed workers is expressed in 192% higher free calcium concentration [Ca(2+)]i and 1.6 times higher μ-calpain activity with respect to non-lead exposed workers. The adenosine triphosphate (ATP) concentration was not significantly different between the two worker groups. No externalization of phosphatidylserine (PS) was found in non-lead exposed workers (lead exposed workers showed 2.82% externalization. Lead intoxication induces eryptosis possibly through a molecular pathway that includes oxidation, depletion of reduced glutathione (GSH), increment of [Ca(2+)], μ-calpain activation and externalization of PS in erythrocytes. Identifying molecular signals that induce eryptosis in lead intoxication is necessary to understand its physiopathology and chronic complications. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Determining tissue-lead levels in large game mammals harvested with lead bullets: human health concerns.

    Science.gov (United States)

    Tsuji, L J S; Wainman, B C; Jayasinghe, R K; VanSpronsen, E P; Liberda, E N

    2009-04-01

    Recently, the use of lead isotope ratios has definitively identified lead ammunition as a source of lead exposure for First Nations people, but the isotope ratios for lead pellets and bullets were indistinguishable. Thus, lead-contaminated meat from game harvested with lead bullets may also be contributing to the lead body burden; however, few studies have determined if lead bullet fragments are present in big game carcasses. We found elevated tissue-lead concentrations (up to 5,726.0 microg/g ww) in liver (5/9) and muscle (6/7) samples of big game harvested with lead bullets and radiographic evidence of lead fragments. Thus, we would advise that the tissue surrounding the wound channel be removed and discarded, as this tissue may be contaminated by lead bullet fragments.

  9. 90 deg.Neutron emission from high energy protons and lead ions on a thin lead target

    CERN Document Server

    Agosteo, S; Foglio-Para, A; Mitaroff, W A; Silari, Marco; Ulrici, L

    2002-01-01

    The neutron emission from a relatively thin lead target bombarded by beams of high energy protons/pions and lead ions was measured at CERN in one of the secondary beam lines of the Super Proton Synchrotron for radiation protection and shielding calculations. Measurements were performed with three different beams: sup 2 sup 0 sup 8 Pb sup 8 sup 2 sup + lead ions at 40 GeV/c per nucleon and 158 GeV/c per nucleon, and 40 GeV/c mixed protons/pions. The neutron yield and spectral fluence per incident ion on target were measured at 90 deg.with respect to beam direction. Monte-Carlo simulations with the FLUKA code were performed for the case of protons and pions and the results found in good agreement with the experimental data. A comparison between simulations and experiment for protons, pions and lead ions have shown that--for such high energy heavy ion beams--a reasonable estimate can be carried out by scaling the result of a Monte-Carlo calculation for protons by the projectile mass number to the power of 0.80-0...

  10. The lead and lead-acid battery industries during 2002 and 2007 in China

    Energy Technology Data Exchange (ETDEWEB)

    Chen, H.Y.; Li, A.J.; Finlow, D.E. [Key Lab of Electrochemical Technology on Energy Storage and Power Generation in Guangdong Universities, School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China)

    2009-06-01

    In the past 15 years, the center of the international lead market has shifted to China. China has become the largest producer of raw and refined lead, plus the largest consumer. This paper reviews the status of the lead and lead-acid battery industries in China, including lead mining, lead refining, secondary lead production, the lead-acid battery industry, new opportunities for lead-acid batteries, and the environmental problems associated with lead and lead-acid batteries. The output of raw and refined lead has increased annually in China, and now accounts for more than 30% of the world total. As a result of a change in the Chinese government's policy regarding the export of lead, plus an increase in the price of lead, the profits of Chinese lead manufacturers were significantly reduced, the trade deficit of the Chinese lead industry increased, the operating rates of lead smelter enterprises greatly reduced, and some small enterprises were forced to shut down. At the present time, an increasing number of enterprises have begun to produce secondary lead, and the scale of production has expanded from tens of tons to tens of thousands of tons. In 2006, the output of secondary lead in China reached 700,000 tons, but outdated technology and equipment limited development of the secondary lead industry. Because of serious pollution problems, raw material shortages, and fierce price competition in the battery market, changes in the development of the lead-acid battery industry have been dramatic; approximately one thousand medium-sized and small lead-acid battery producers have been closed in the past 3 years. The output of large lead-acid battery enterprises has not been reduced, however, as a result of their manufacturing technology and equipment being comparable to those in other advanced industrial countries. In China, the flourishing development of electric bicycles, electric tricycles, and photovoltaic energy systems should provide ongoing opportunities for

  11. The lead and lead-acid battery industries during 2002 and 2007 in China

    International Nuclear Information System (INIS)

    Chen, H.Y.; Li, A.J.; Finlow, D.E.

    2009-01-01

    In the past 15 years, the center of the international lead market has shifted to China. China has become the largest producer of raw and refined lead, plus the largest consumer. This paper reviews the status of the lead and lead-acid battery industries in China, including lead mining, lead refining, secondary lead production, the lead-acid battery industry, new opportunities for lead-acid batteries, and the environmental problems associated with lead and lead-acid batteries. The output of raw and refined lead has increased annually in China, and now accounts for more than 30% of the world total. As a result of a change in the Chinese government's policy regarding the export of lead, plus an increase in the price of lead, the profits of Chinese lead manufacturers were significantly reduced, the trade deficit of the Chinese lead industry increased, the operating rates of lead smelter enterprises greatly reduced, and some small enterprises were forced to shut down. At the present time, an increasing number of enterprises have begun to produce secondary lead, and the scale of production has expanded from tens of tons to tens of thousands of tons. In 2006, the output of secondary lead in China reached 700,000 tons, but outdated technology and equipment limited development of the secondary lead industry. Because of serious pollution problems, raw material shortages, and fierce price competition in the battery market, changes in the development of the lead-acid battery industry have been dramatic; approximately one thousand medium-sized and small lead-acid battery producers have been closed in the past 3 years. The output of large lead-acid battery enterprises has not been reduced, however, as a result of their manufacturing technology and equipment being comparable to those in other advanced industrial countries. In China, the flourishing development of electric bicycles, electric tricycles, and photovoltaic energy systems should provide ongoing opportunities for the

  12. Bulk diffusion and solubility of silver and nickel in lead, lead-silver and lead-nickel solid solutions

    International Nuclear Information System (INIS)

    Amenzou-Badrour, H.; Moya, G.; Bernardini, J.

    1988-01-01

    The results of a study of solubility and bulk diffusion of /sup 110/Ag and /sup 63/Ni in lead, lead-silver and lead-nickel solid solutions in the temperature range 220 to 88 0 C are reported. Owing to the low solubility of silver and nickel in lead, Fick's solution corresponding to the boundary condition of a constant concentration of solute at the surface has been used. Depth profile concentration analysis suggests a fundamental difference between the diffusion mechanisms of silver and nickel. Since silver penetration profiles in pure lead give diffusion coefficients independent of the penetration depth and silver concentration, it is suggested that slight decreases of silver diffusivity in lead-silver solid solutions have no significance. This implies that the interstitial silver atoms do not associate significantly with each other to form Ag-Ag dimers. In contrast, different behaviors of /sup 63/Ni depth profile concentration in pure lead and saturated PbNi solid solutions agree with a Ni-Ni interaction leading to the formation of less mobile dimers near the surface in pure lead

  13. Lead in soils, plants and animals

    Energy Technology Data Exchange (ETDEWEB)

    Scheltinga, H

    1955-01-01

    The toxicity of lead for plants is small, except in the case of water cultures. Animals can absorb more lead without toxic effect than was previously expected. This applies to acute poisoning as well as chronic poisoning. As a result of experiments over many years (Allcroft and Blaxter, 1950) the possibility of chronic lead poisoning has been found to be minute. Rations containing 240 mg lead/kg dried fodder, given daily over a period of three years, did not cause any poisoning at all in cattle thus fed. Where lead poisoning did take place, it was observed that the ratio of lead in the dried fodder was > 1000 mg/kg; the proportion was generally much higher. In normal cases grass contains only 5 to 15 mg lead/kg. The total lead content of samples from arable land was 10 to 25 mg/kg soil. For grassland on peat or clay the amount was slightly higher. The influence on the lead status of soils and plants of fertilizing with compost or copper slag flour, both containing a small percentage of lead, proved to be negligible. It is definite that in normal use, these fertilizers cannot cause any danger for either plant or animal. 24 references, 3 tables.

  14. Exposure to lead from intake of coffee

    DEFF Research Database (Denmark)

    Hansen, Max; Sloth, Jens Jørgen; Rasmussen, Rie Romme

    Food and beverages is one of the primary sources of intake of and exposure to lead, with beverages accounting for almost 50%. Previous studies from Denmark have estimated that the intake of lead from coffee is very high and may contribute to up to 20% of the total lead intake from food and bevera......Food and beverages is one of the primary sources of intake of and exposure to lead, with beverages accounting for almost 50%. Previous studies from Denmark have estimated that the intake of lead from coffee is very high and may contribute to up to 20% of the total lead intake from food...... and beverages. This estimate is, however, based on older, non-published data. In the current project extensive chemical analyses of coffee beans, drinking water and ready-to-drink coffee have been performed. The results hereof have been compared to calculations of the total intake of lead from food...... and beverages. The results show that the intake of lead from coffee is considerably lower than previously estimated and account for 4.2% and 3.3% of the total lead intake from food and beverages for Danish men and women, respectively. It can generally be concluded that the intake of lead from coffee is low...

  15. Air pollution from lead added to gasoline

    Energy Technology Data Exchange (ETDEWEB)

    Dingeon, B; Collombel, C

    1973-01-01

    General hygienic and toxicological problems of lead added to gasoline are discussed. Lead emitted by motor vehicles pollutes the air especially in cities and along highways, and is accumulated by soil and plants. The lead levels found in the blood of subjects living in cities and near highways was significantly higher than in rural dwellers. Close correlation between the atmospheric lead concentration and the carbon monoxide concentration as well as the traffic density was established, indicating traffic as the source of atmospheric lead. The effect of traffic on the atmospheric lead concentration extended over a distance of up to 4 km. The lead, emitted by motor vehicles in the form of submicron particles, is retained in the organism at rates of 5-10 percent following ingestion, and at rates of 30-50 percent when inhaled. Lead is partially excreted by the liver, kidney, hair, and nails. Some 95 percent of the retained lead is found in the blood, and accumulation in the bones with potential mobilization due to increases in the corticosteroid level was observed. Exposure to lead can be diagnosed by basophil granulation test, urine delta-aminolevulinic acid test, and delta-aminolevulinic acid dehydratase test.

  16. Lead contamination of paint remediation workers' vehicles.

    Science.gov (United States)

    Boraiko, Carol; Wright, Eva M; Ralston, Faye

    2013-03-01

    Exposure to lead has been shown to be harmful to adults; it is a teratogen, it can damage the peripheral nervous system, and it adversely affects the reproductive system. Professional lead-based paint remediation workers are at risk of exposure to lead dust. The authors' study was conducted to determine if these remediation workers transfer lead from their work site to their vehicles and then potentially expose their families. It was hypothesized that remediation workers transported the lead from the remediation work site to the floorboards of their vehicles due to not following required protective equipment use. The laboratory's level of quantitation for lead on the wipe samples, 10 microg/ft2, was used to indicate lead contamination. This level was exceeded in 50% of the floorboards sampled. These results confirm that many vehicle floorboards used by remediation workers are contaminated with lead dust, potentially resulting in transfer of lead dust. The ultimate detrimental outcome could be the transfer of lead particles to other family members, causing the poisoning of a child or other at-risk person.

  17. Lead exposures from varnished floor refinishing.

    Science.gov (United States)

    Schirmer, Joseph; Havlena, Jeff; Jacobs, David E; Dixon, Sherry; Ikens, Robert

    2012-01-01

    We evaluated the presence of lead in varnish and factors predicting lead exposure from floor refinishing and inexpensive dust suppression control methods. Lead in varnish, settled dust, and air were measured using XRF, laboratory analysis of scrape and wipe samples, and National Institute for Occupational Safety and Health (NIOSH) Method 7300, respectively, during refinishing (n = 35 homes). Data were analyzed using step-wise logistic regression. Compared with federal standards, no lead in varnish samples exceeded 1.0 mg/cm(2), but 52% exceeded 5000 ppm and 70% of settled dust samples after refinishing exceeded 40 μg/ft(2). Refinishing pre-1930 dwellings or stairs predicted high lead dust on floors. Laboratory analysis of lead in varnish was significantly correlated with airborne lead (r = 0.23, p = 0.014). Adding dust collection bags into drum sanders and HEPA vacuums to edgers and buffers reduced mean floor lead dust by 8293 μg Pb/ft(2) (pairborne lead exposures to less than 50 μg/m(3). Refinishing varnished surfaces in older housing produces high but controllable lead exposures.

  18. Study of core flow distribution for small modular natural circulation lead or lead-alloy cooled fast reactors

    International Nuclear Information System (INIS)

    Chen, Zhao; Zhao, Pengcheng; Zhou, Guangming; Chen, Hongli

    2014-01-01

    Highlights: • A core flow distribution calculation code for natural circulation LFRs was developed. • The comparison study between the channel method and the CFD method was conducted. • The core flow distribution analysis and optimization design for a 10MW natural circulation LFR was conducted. - Abstract: Small modular natural circulation lead or lead-alloy cooled fast reactor (LFR) is a potential candidate for LFR development. It has many attractive advantages such as reduced capital costs and inherent safety. The core flow distribution calculation is an important issue for nuclear reactor design, which will provide important input parameters to thermal-hydraulic analysis and safety analysis. The core flow distribution calculation of a natural circulation LFR is different from that of a forced circulation reactor. In a forced circulation reactor, the core flow distribution can be controlled and adjusted by the pump power and the flow distributor, while in a natural circulation reactor, the core flow distribution is automatically adjusted according to the relationship between the local power and the local resistance feature. In this paper, a non-uniform heated parallel channel flow distribution calculation code was developed and the comparison study between the channel method and the CFD method was carried out to assess the exactness of the developed code. The core flow distribution analysis and optimization design for a 10MW natural circulation LFR was conducted using the developed code. A core flow distribution optimization design scheme for a 10MW natural circulation LFR was proposed according to the optimization analysis results

  19. Safety considerations of lithium lead alloy as a fusion reactor breeding material

    International Nuclear Information System (INIS)

    Jeppson, D.W.; Muhlestein, L.D.

    1985-01-01

    Test results and conclusions are presented for lithium lead alloy interactions with various gas atmospheres, concrete and potential reactor coolants. The reactions are characterized to evaluate the potential of volatilizing and transporting radioactive species associated with the liquid breeder under postulated fusion reactor accident conditions. The safety concerns identified for lithium lead alloy reactions with the above materials are compared to those previously identified for a reference fusion breeder material, liquid lithium. Conclusions made from this comparison are also included

  20. Application of a Complex Lead Compensator for a Laser Guided Missile

    Science.gov (United States)

    Akhila, M. R.; Gopika, S.; Abraham, R. J.

    2013-01-01

    This paper discusses the application of a lead compensator with complex pole and complex zero for a missile. It is compared with a lead compensator with real pole and real zero. A typical laser guided missile control system is considered for the performance comparison of both the compensators. Simulation studies carried out with MATLAB brings out the scope of using complex compensator in missile guided systems.

  1. The refining of secondary lead for use in advanced lead-acid batteries

    International Nuclear Information System (INIS)

    Ellis, Timothy W.; Mirza, Abbas H.

    2010-01-01

    Secondary lead, i.e. material produced by the recycling of lead-acid batteries has become the primary source of lead in much of the world. This has been important to the secondary lead industry as other uses have dwindled, e.g. lead based pigments, chemicals, fuel additives, solders and CRT glasses. Presently, battery manufacturing accounts for greater than 80% of lead consumption while recycled lead accounts for approximately the same market share of lead supply. These two facts strongly demonstrate the battery manufacturing and recycled lead are intimately coupled in everyday life. In this paper we will explore how recycled lead has become the material of choice for battery construction through the development of a recovery and refining process that exceeds the industries requirements. Particular focus will be on addressing the results presented by Prengaman on the effects of contaminant or tramp elements on gassing in lead-acid batteries. (author)

  2. High human exposure to lead through consumption of birds hunted with lead shot

    International Nuclear Information System (INIS)

    Johansen, P.; Asmund, G.; Riget, F.

    2004-01-01

    Lead shot contaminates the edible parts of birds so that tolerable human lead intake is exceeded. - We assess lead contamination of Greenland seabirds killed with lead shot having studied thick-billed murre and common eider, the two most important species in the diet. The lead concentration is very high in meat of eiders killed with lead shot (mean 6.1 μg/g-wet wt, 95% CL 2.1-12). This level is about 44 times higher than in drowned eiders and eight times higher than in shot murres. Analyzing whole breasts instead of sub-samples reveals about seven times higher lead levels in birds' meat. We conclude that in some cases the lead intake by Greenland bird eaters will largely exceed the FAO/WHO tolerable lead intake guideline and that lead shot is a more important source of lead in the diet than previously estimated

  3. Lead pollution: lead content in milk from cows fed on contaminated forages

    Energy Technology Data Exchange (ETDEWEB)

    Sapetti, C; Arduino, E; Durio, P

    1973-01-01

    Lead toxicity is reviewed, and the history of the lead poisoning is described. Much of the lead pollution in soil is due to automobile exhaust. Two milk cows were fed forage with added lead acetate. The 20 kg of lead corresponded to 50 ppm, a level that is often found in hays near major highways. The cows milk was then analyzed for lead content. During the first and second phase of administration of lead salts, the milk cows did not show any evident symptoms of intoxication. The lead in the milk did have a marked correlation with the administered lead. The lead doses did not last long enough for chronic symptoms to begin. The dosage of lead in milk, due to the facility of drawing samples and the relevant levels of response, could represent a valid method for diagnosing incipient chronic intoxications.

  4. Isolation of radioactive thallium from lead targets

    International Nuclear Information System (INIS)

    Kozlova, M.D.; Sevast'yanova, A.S.; Malinin, A.B.; Kurenkov, N.V.

    1989-01-01

    Two methods of thallium-201 preperation from Pb-targets irradiated with protons: precipitation-extraction (1) and extraction (2) - are developed. When the target irraiated is extracted during the time necessary for bismuth-201 transformation into lead-201, lead macroquantity containing lead-201 was separated from undesirable thallium radionuclides, which are formed in direct nuclear reactions. The lead fraction was extracted to accumulate thallium-201, and it was separated from lead mocroquantity. The target was dissolved in the nitric acid. The 1st method differs from the 2nd one by the fact that before thallium-201 extraction, lead was precipitaed by the nitric acid. The 1st method permits to separate thallium-201 with chemical yield not less than 90 %, the 2nd one - ≥95 %. 2 refs

  5. Narrow Lead Aprons under Medical Fluoroscopy Procedures

    International Nuclear Information System (INIS)

    Ben-Shlomo, A.

    2014-01-01

    Lead aprons are the major protective item of the medical staff whose work involves x-ray exposure. Heart catheterization and angiography procedures represent the most common exposures of the medical staff. The lead equivalent thickness of lead aprons worn by the medical staff is defined by many national standards. The frontal side of the aprons should be 0.25 mm lead equivalent at working conditions under 100 kV, 0.35 mm for working conditions above 100 kV, and 0.5 mm for heart catheterization and angiography. The back side of the body needs less protection and usually is covered by 0.25 mm of lead equivalent. The lead equivalent thickness is defined at the 80 kV level

  6. A review of lead poisoning in swans

    Science.gov (United States)

    Blus, L.J.

    1994-01-01

    Nearly 10,000 swans of six species or subspecies from 14 countries have died from poisoning caused by lead that originated from ingestion of fishing weights, shotgun pellets (shot), or contaminated vegetation or sediments associated with mining and smelting wastes. Lead contamination in mute swans in England caused local population declines during the late 1970s and 1980s. More tundra swans died from lead poisoning than any other species. The extreme record involved an estimated 7200 tundra swans that died over five winters at one locality in North Carolina. The recent legislation to ban lead fishing weights in most of England and Wales and recent replacement of lead shot with steel shot for waterfowl hunting in the United States and a few areas of Europe, including Denmark, are expected to reduce the incidence of lead poisoning in swans.

  7. Radiation effects on lead silicate glass surfaces

    International Nuclear Information System (INIS)

    Wang, P.W.; Zhang, L.P.; Borgen, N.; Pannell, K.

    1996-01-01

    Radiation-induced changes in the microstructure of lead silicate glass were investigated in situ under Mg K α irradiation in an ultra-high vacuum (UHV) environment by X-ray photoelectron spectroscopy (XPS). Lead-oxygen bond breaking resulting in the formation of pure lead was observed. The segregation, growth kinetics and the structural relaxation of the lead, with corresponding changes in the oxygen and silicon on the glass surfaces were studied by measuring the time-dependent changes in concentration, binding energy shifts, and the full width at half maximum. A bimodal distribution of the oxygen XPS signal, caused by bridging and non-bridging oxygens, was found during the relaxation process. All experimental data indicate a reduction of the oxygen concentration, a phase separation of the lead from the glass matrix, and the metallization of the lead occurred during and after the X-ray irradiation. (author)

  8. Apparatus and methods for purifying lead

    Science.gov (United States)

    Tunison, Harmon M.

    2016-01-12

    Disclosed is an exemplary method of purifying lead which includes the steps of placing lead and a fluoride salt blend in a container; forming a first fluid of molten lead at a first temperature; forming a second fluid of the molten fluoride salt blend at a second temperature higher than the first temperature; mixing the first fluid and the second fluid together; separating the two fluids; solidifying the molten fluoride salt blend at a temperature above a melting point of the lead; and removing the molten lead from the container. In certain exemplary methods the molten lead is removed from the container by decanting. In still other exemplary methods the molten salt blend is a Lewis base fluoride eutectic salt blend, and in yet other exemplary methods the molten salt blend contains sodium fluoride, lithium fluoride, and potassium fluoride.

  9. Solubility of iron in liquid lead

    International Nuclear Information System (INIS)

    Ali-Khan, I.

    1981-01-01

    The use of liquid lead in high temperature chemical and metallurgical processes is well known. The structural materials applied for the containment of these processes are either iron base alloys or possess iron as an alloying element. Besides that, lead itself is alloyed in some steels to achieve some very useful properties. For understanding the effect of liquid lead in such structural materials, it is important to determine the solubility of iron in liquid lead which would also be indicative of the stability of these alloys. At the institute of reactor materials of KFA Juelich, investigations have been conducted to determine the solubility of iron in liquid lead up to a temperature of about 1000 0 C. In this presentation the data concerning the solubility of iron in liquid lead are brought up to date and discussed including the results of our previous investigations. (orig.)

  10. Lead in Glasgow street dirt and soil

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, J G [Univ. of Glasgow; Lyon, T D.B.

    1977-07-01

    The levels of lead in city street dirt and in soil from various locations in Glasgow were investigated during spring 1976. Lead concentrations in street dirt ranged from 150 to 2300 ppM, mean 960 ppM, and were significantly elevated with respect to the observed ''natural'' level of 78 ppM. Lead derived from anti-knock compounds in petrol and introduced to the environment via automobile exhausts was clearly implicated as the main source of lead pollution in a series of soil lead measurements at the centre and periphery of eight Glasgow parks. Various chemical leaching techniques were employed and compared. Less than 5 percent of street dirt and soil lead was found to be associated with the organic phase.

  11. Petrol with isotopically differentiated lead added

    International Nuclear Information System (INIS)

    Magi, F.; Facchetti, S.; Garibaldi, P.

    1975-01-01

    An experiment is proposed aimed at determining the role of motor traffic in the pollution of the environment by lead, in particular of air, soil, vegetation, food and the human body. The technique of determining the isotopic composition of lead, used in the right way, should enable the whole problem to be solved. It is intended to add lead with a constant isotopic composition different from that of normally occuring lead, whether natural in origin or otherwise, to petrol in at least two regions of Italy. Analyses of lead samples taken from the principal mines have shown that Australian lead (Broken Hill Mine) has quite a different isotopic composition. This lead will therefore be used to prepare the antiknock additives for petrol sold in the regions in question. Adequate sampling should make it possible to determine the contribution to pollution of lead from motor vehicle exhausts. The regions chosen for the experiment are Piedmont (city and province of Turin) and Sardinia (city and province of Cagliari) - the first because of its high traffic density and level of industrialization, the second because of its remoteness and the lead content of the soil, which may affect food. Both regions present favourable conditions for supplying petrol of the intended type. The experiment is intended to last three years; the petrol with Australian lead will be marketed for a period of 18 months. The first results of analyses of the isotopic composition of lead contained in atmospheric dust in the city of Turin and of lead from a number of blood samples are reported in the paper

  12. Verification of radiation exposure using lead shields

    International Nuclear Information System (INIS)

    Hayashida, Keiichi; Yamamoto, Kenyu; Azuma, Masami

    2016-01-01

    A long time use of radiation during IVR (intervention radiology) treatment leads up to an increased exposure on IVR operator. In order to prepare good environment for the operator to work without worry about exposure, the authors examined exposure reduction with the shields attached to the angiography instrument, i. e. lead curtain and lead glass. In this study, the lumber spine phantom was radiated using the instrument and the radiation leaked outside with and without shields was measured by the ionization chamber type survey meter. The meter was placed at the position which was considered to be that for IVR operator, and changed vertically 20-100 cm above X-ray focus by 10 cm interval. The radiation at the position of 80 cm above X-ray focus was maximum without shield and was hardly reduced with lead curtain. However, it was reduced with lead curtain plus lead glass. Similar reduction effects were observed at the position of 90-100 cm above X-ray focus. On the other hand, the radiation at the position of 70 cm above X-ray focus was not reduced with either shield, because that position corresponded to the gap between lead curtain and lead glass. The radiation at the position of 20-60 cm above X-ray focus was reduced with lead curtain, even if without lead glass. These results show that lead curtain and lead glass attached to the instrument can reduce the radiation exposure on IVR operator. Using these shields is considered to be one of good means for IVR operator to work safely. (author)

  13. Forecasting Irish Inflation: A Composite Leading Indicator

    OpenAIRE

    Quinn, Terry; Mawdsley, Andrew

    1996-01-01

    This paper presents the results of research into the construction of a composite leading indicator of the Irish rate of inflation, as measured by the annual percentage change in the Consumer Price Index (CPI). It follows the work of Fagan and Fell (1994) who applied the business cycle leading indicator methodology, initially established by Mitchell and Burns (1938,1946), to construct a composite leading indicator of the Irish business cycle.

  14. Lead titanate nanotubes synthesized via ion-exchange method: Characteristics and formation mechanism

    International Nuclear Information System (INIS)

    Song Liang; Cao Lixin; Li Jingyu; Liu Wei; Zhang Fen; Zhu Lin; Su Ge

    2011-01-01

    Highlights: → Lead titanate nanotubes PbTi 3 O 7 were firstly synthesized by ion-exchange method. → Sodium titanate nanotubes have ion exchangeability. → Lead titanate nanotubes show a distinct red shift on absorption edge. - Abstract: A two-step method is presented for the synthesis of one dimensional lead titanate (PbTi 3 O 7 ) nanotubes. Firstly, titanate nanotubes were prepared by an alkaline hydrothermal process with TiO 2 nanopowder as precursor, and then lead titanate nanotubes were formed through an ion-exchange reaction. We found that sodium titanate nanotubes have ion exchangeability with lead ions, while protonated titanate nanotubes have not. For the first time, we distinguished the difference between sodium titanate nanotubes and protonated titanate nanotubes in the ion-exchange process, which reveals a layer space effect of nanotubes in the ion-exchange reaction. In comparison with sodium titanate, the synthesized lead titanate nanotubes show a narrowed bandgap.

  15. High-Temperature Lead-Free Solder Alternatives: Possibilities and Properties

    DEFF Research Database (Denmark)

    High-temperature solders have been widely used as joining materials to provide stable interconnections that resist a severe thermal environment and also to facilitate the drive for miniaturization. High-lead containing solders have been commonly used as high-temperature solders. The development...... of high-temperature lead-free solders has become an important issue for both the electronics and automobile industries because of the health and environmental concerns associated with lead usage. Unfortunately, limited choices are available as high-temperature lead-free solders. This work outlines...... the criteria for the evaluation of a new high-temperature lead-free solder material. A list of potential ternary high-temperature lead-free solder alternatives based on the Au-Sn and Au-Ge systems is proposed. Furthermore, a comprehensive comparison of the high-temperature stability of microstructures...

  16. 'Do lead rubber aprons pose an infection risk?'

    International Nuclear Information System (INIS)

    Boyle, Helen; Strudwick, Ruth M.

    2010-01-01

    This study was carried out in order to establish whether infection control measures were being undertaken sufficiently on lead rubber aprons within a diagnostic imaging department in the east of England. This study involved the swabbing of a sample of 15 lead rubber aprons used within different areas of the department. Swabs were taken from the area on the underside of the shoulders and from the front of the apron. Each apron was firstly swabbed to determine the current level of microorganism contamination (determination of baseline data) and then again after recommended cleaning with detergent and water (the production of a standard). Comparisons were then made between the number of microorganisms' present (colony forming units/cm 2 ) pre and post-cleaning at each location. Additionally, post-cleaning data was compared for each location. All aprons were found to be contaminated with microorganisms, those identified were Coagulase-negative staphylococci, Staphylococcus aureus, Bacillus, Diphtheroids and some fungal spores. No Methicillin resistant strains of Staphylococcus aureus (MRSA) were identified. Recommended cleaning with detergent and water was found to significantly reduce the amount of microorganisms present (the detergent used was Hospec general purpose neutral liquid detergent). Comparisons of the sample sites found that the front of the apron had lower levels of microorganism contamination post-cleaning than the site at the underside of the shoulders. The results suggest that the lead rubber aprons were not being cleaned sufficiently which has infection control implications for the department. In order for cross contamination to be kept to a minimum an effective infection control policy needs to be employed and this should be to carry out regular cleaning with detergent and water which has been shown can significantly reduce contamination.

  17. Load Dependent Lead Times and Sustainability

    DEFF Research Database (Denmark)

    Pahl, Julia; Voss, Stefan

    2016-01-01

    to prevent decreased quality or waste of production parts and products. This gains importance because waiting times imply longer lead times charging the production system with work in process inventories. Longer lead times can lead to quality losses due to depreciation, so that parts need to be reworked...... if possible or discarded. But return flows of products for rework or remanufacturing actions significantly complicate the production planning process. We analyze sustainability options with respect to lead time management by formulating a comprehensive mathematical model. We consider a deterministic, mixed...

  18. Moveable Leading Edge Device for a Wing

    Science.gov (United States)

    Pitt, Dale M. (Inventor); Eckstein, Nicholas Stephen (Inventor)

    2013-01-01

    A method and apparatus for managing a flight control surface system. A leading edge section on a wing of an aircraft is extended into a deployed position. A deformable section connects the leading edge section to a trailing section. The deformable section changes from a deformed shape to an original shape when the leading edge section is moved into the deployed position. The leading edge section on the wing is moved from the deployed position to an undeployed position. The deformable section changes to the deformed shape inside of the wing.

  19. Lead in some food crops and trees

    Energy Technology Data Exchange (ETDEWEB)

    Warren, H V; Delavault, R E

    1962-02-01

    An investigation has been made of the lead content of trees and some of the more common vegetables and cereals (maize, cabbage, potatoes, carrots, beets, onions, peas, hops, oats, rhubarb, lettuce, cauliflower, leeks, barley, rye, and wheat) grown in British Columbia and in Great Britain. The lead content of the lime, yew, willow, birch, oak, ash, hazel and cypress was determined. It was concluded that in areas where soils have an abnormally high lead content, food products may acquire up to ten times as much lead, or more, than those grown on normal soil.

  20. Lead level in mallard (Anas platyrhynchos

    Directory of Open Access Journals (Sweden)

    Ioan Macinic

    2012-12-01

    Full Text Available The study was carried out on a hunting ground belonging to AJVPS Arad, county Arad. Lead (Pb was determined in Mallard (Anas platyrhynchos tissues (muscles and organs (liver, kidneys to see the contamination level of this tissues and organs and also the impact on humans health because in our days more and more wild game meat take a increasing percentage in humans food ratio. The Mallard is one of the most widespread duck species. Mallard has 50-62 cm length, 800-1400 g weight and lives about 11 years. It prefers rivers and shallow pounds with a lot of reed. It is a migratory species that is flying long distances to find food and unfrozen water, so it is a exposed to lead contamination that is under dust form in atmosphere. But another reason why lead level in Mallard can be higher that in other flying specie (pheasant, woodcock, quail, and pigeons are the lead shot shells that are used for duck hunting. It is known that the ducks can ingest these lead shot shells and so they are often exposed to lead intoxications. This is why in our days more ammunition for waterfowl are steel made or different type of alloys. Lead is known to be one of the most common pollutants with a large range of effects on human health: lead affects nervous system, digestive tract, kidneys, bones, enzymes. Lead has also mutagenic effect, carcinogenic effect, teratogenic effect.

  1. Production Planning with Load Dependent Lead Times

    DEFF Research Database (Denmark)

    Pahl, Julia

    2005-01-01

    Lead times impact the performance of the supply chain significantly. Although there is a large literature concerning queuing models for the analysis of the relationship between capacity utilization and lead times, and there is a substantial literature concerning control and order release policies...... that take lead times into consideration, there have been only few papers describing models at the aggregate planning level that recognize the relationship between the planned utilization of capacity and lead times. In this paper we provide an in-depth discussion of the state-of-the art in this literature......, with particular attention to those models that are appropriate at the aggregate planning level....

  2. Scale-dependent spatial variability in peatland lead pollution in the southern Pennines, UK

    International Nuclear Information System (INIS)

    Rothwell, James J.; Evans, Martin G.; Lindsay, John B.; Allott, Timothy E.H.

    2007-01-01

    Increasingly, within-site and regional comparisons of peatland lead pollution have been undertaken using the inventory approach. The peatlands of the Peak District, southern Pennines, UK, have received significant atmospheric inputs of lead over the last few hundred years. A multi-core study at three peatland sites in the Peak District demonstrates significant within-site spatial variability in industrial lead pollution. Stochastic simulations reveal that 15 peat cores are required to calculate reliable lead inventories at the within-site and within-region scale for this highly polluted area of the southern Pennines. Within-site variability in lead pollution is dominant at the within-region scale. The study demonstrates that significant errors may be associated with peatland lead inventories at sites where only a single peat core has been used to calculate an inventory. Meaningful comparisons of lead inventories at the regional or global scale can only be made if the within-site variability of lead pollution has been quantified reliably. - Multiple peat cores are required for accurate peatland Pb inventories

  3. Scale-dependent spatial variability in peatland lead pollution in the southern Pennines, UK.

    Science.gov (United States)

    Rothwell, James J; Evans, Martin G; Lindsay, John B; Allott, Timothy E H

    2007-01-01

    Increasingly, within-site and regional comparisons of peatland lead pollution have been undertaken using the inventory approach. The peatlands of the Peak District, southern Pennines, UK, have received significant atmospheric inputs of lead over the last few hundred years. A multi-core study at three peatland sites in the Peak District demonstrates significant within-site spatial variability in industrial lead pollution. Stochastic simulations reveal that 15 peat cores are required to calculate reliable lead inventories at the within-site and within-region scale for this highly polluted area of the southern Pennines. Within-site variability in lead pollution is dominant at the within-region scale. The study demonstrates that significant errors may be associated with peatland lead inventories at sites where only a single peat core has been used to calculate an inventory. Meaningful comparisons of lead inventories at the regional or global scale can only be made if the within-site variability of lead pollution has been quantified reliably.

  4. A Double-Edged Sword? On the Benefit, Detriment, and Net Effect of Dimensional Comparison on Self-Concept

    Science.gov (United States)

    Müller-Kalthoff, Hanno; Jansen, Malte; Schiefer, Irene M.; Helm, Friederike; Nagy, Nicole; Möller, Jens

    2017-01-01

    Dimensional comparison theory (DCT; Möller & Marsh, 2013) assumes that students compare their academic achievement intraindividually across domains to form domain-specific self-concepts. Upward dimensional comparisons are believed to lead to lower self-concepts in the worse-off domain, while downward dimensional comparisons should lead to…

  5. EMERGING TECHNOLOGY BULLETIN: RECLAMATION OF LEAD FROM SUPERFUND WASTE MATERIAL USING SECONDARY LEAD SMELTERS

    Science.gov (United States)

    This process involves incorporating lead-contaminated Superfund waste with the regular feed to a secondary lead smelter. Since secondary lead smelters already recover lead from recycled automobile batteries, it seems likely that this technology could be used to treat waste from ...

  6. Lead dust in Broken Hill homes: effect of remediation on indoor lead levels.

    Science.gov (United States)

    Boreland, F; Lyle, D M

    2006-02-01

    This study was undertaken to determine whether home remediation effectively reduced indoor lead levels in Broken Hill, a long-established silver-lead-zinc mining town in outback Australia. A before-after study of the effect of home remediation on indoor lead levels was embedded into a randomized controlled trial of the effectiveness of remediation for reducing elevated blood lead levels in young children. Moist towelettes were used to measure lead loading (microg/m2) on internal windowsills and internal and entry floors of 98 homes; samples were collected before, immediately after, and 2, 4, 6, 8, and 10 months after remediation. Data were log(10) transformed for the analysis. Remediation reduced average indoor lead levels by approximately 50%, and lead levels remained low for the duration of the follow-up period (10 months). The greatest gains were made in homes with the highest initial lead levels; homes with low preremediation lead levels showed little or no benefit. Before remediation, homes located in areas with high soil lead levels or with "poor" dust proofing had higher lead levels than those in areas with lower soil lead levels or with "medium" or "good" dust proofing; these relative differences remained after remediation. There was no evidence that lead loading was reduced by an increased opportunity to become aware of lead issues. We conclude that remediation is an effective strategy for reducing the lead exposure of children living in homes with high indoor lead levels.

  7. The relationship between environmental lead and blood lead in children : a study in environmental epidemiology

    NARCIS (Netherlands)

    Brunekreef, B.

    1985-01-01

    This study deals with the relationship between environmental lead and blood lead in children.
    Chapter 1 provides a summary of the environmental health aspects of lead. The occurrence of lead in the environment and in man is described; children are discussed as a population at

  8. Effect of lead exposure on the immune response of some occupationally exposed individuals

    International Nuclear Information System (INIS)

    Mishra, Kamla Prasad; Singh, Vijay Kumar; Rani, Reena; Yadav, Virendra Singh; Chandran, Vinod; Srivastava, Satya Prakash; Seth, Prahlad Kishore

    2003-01-01

    Lead is a ubiquitous pollutant in the industrial environment, which poses serious threats to human health. In the past 20 years increasing attention has been paid to the effects of lead exposure on health. This toxic metal alters the immune response of animals as well as humans. To study the immunological effects of occupational exposure to lead, we examined lymphocyte proliferation, natural killer (NK) cell cytotoxicity and interferon-γ production with peripheral blood mononuclear cells (PBMCs) of individuals occupationally exposed to lead. We selected three different groups of individuals exposed to lead: three-wheeler drivers (30), battery workers (34) and silver jewelery makers (20); and unexposed healthy volunteers (30) as control for comparison. Our results indicate that though lymphocyte proliferation to phytohaemagglutinin (PHA) is inhibited in lead exposed individuals as compared with unexposed volunteers, there is no correlation between inhibition of lymphocyte proliferation and blood lead level. NK cell cytotoxicity remains unaffected in individuals exposed to lead as compared with controls. On the other hand, we observed that interferon-γ (IFN-γ) was significantly elevated in T cell mitogen, PHA, stimulated PBMCs culture supernatant of lead exposed individuals. We found significant positive correlation between blood lead levels and IFN-γ produced in culture supernatant on stimulation with PHA. In brief, this study demonstrates that lead can affect the immune response of the occupationally exposed individuals such as three-wheeler drivers, battery reconditioning workers and silver jewelery makers

  9. Relative effects of climate and source strength on atmospheric lead concentrations in Auckland, New Zealand

    Science.gov (United States)

    Power, H. C.; de Freitas, C. R.; Hay, J. E.

    1992-06-01

    Atmospheric lead levels were examined to assess the consequences of the 46 percent reduction in the lead content of premium grade petrol in New Zealand. Since this change was implemented in July 1986 observed levels of atmospheric lead decreased by 38 percent, but all or part of this reduction may have been due to factors other than fluctuations in lead emissions, notably variations in climate. Analysis of detailed atmospheric lead, meteorological and traffic data measured contemporaneously provided insight into the atmospheric processes influencing lead levels in Auckland and formed the basis of a statistical model capable of predicting monthly lead concentrations. The model was used to predict lead levels in Auckland for the period July 1986 through to July 1989 in the absence of any reduction in the lead content of petrol. Comparison with values observed for the same period showed that all of the reduction in atmospheric lead levels since July 1986 can be attributed to the reduction in the lead content of petrol. Policy planning implications of such a finding are considered.

  10. Lead, arsenic, and copper content of crops grown on lead arsenate-treated and untreated soils

    Energy Technology Data Exchange (ETDEWEB)

    Chisholm, D

    1972-01-01

    Increased lead and arsenic concentrations in the surface soil (0-15 cm), resulting from applications of lead arsenate (PbHAs0/sub 1/), increased both lead and arsenic levels in crops grown on treated plots. The lead levels in some crops approached or exceeded the Canadian residue tolerance of 2.0 ppM. Lead arsenate soil treatments did not affect copper absorption by crops. On areas such as old orchard land contaminated with lead arsenate residues it may be advisable to ascertain crops, and also to determine the lead affinity and arsenic sensitivity of the plants to be grown.

  11. Lead: Aspects of its ecology and environmental toxicity. [physiological effects of lead compound contamination of environment

    Science.gov (United States)

    Siegel, S. M.

    1973-01-01

    An analysis of lead toxicity in the Hawaiian environment was conducted. It was determined that lead enters the environment as an industrial contaminant resulting from the combustion of leaded gasoline. The amount of lead absorbed by the plants in various parts of the Hawaiian Islands is reported. The disposition of lead in the sediments of canals and yacht basins was investigated. The methods for conducting the surveys of lead content are described. Possible consequences of continued environmental pollution by burning leaded gasoline are discussed.

  12. Assessment of the body burden of chelatable lead: a model and its application to lead workers

    Energy Technology Data Exchange (ETDEWEB)

    Araki, S.; Ushio, K.

    1982-05-01

    A hypothetical model was introduced to estimate the body burden of chelatable lead from the mobilisation yield of lead by calcium disodium ethylenediamine tetra-acetate. It was estimated that, on average, 14 and 19% of the body burden was mobilized into the urine during the 24 hours after an injection of 53.4 mumol and 107 mumol CaEDTA per kg bodyweight, respectively. The body burden of chelatable lead ranged from 4 mumol to 120 mumol in lead workers with blood lead concentrations of 0.3-2.9 mumol/kg. There were linear relationships between blood lead concentrations and body burden of chelatable lead on a log scale.

  13. Constraining recent lead pollution sources in the North Pacific using ice core stable lead isotopes

    Science.gov (United States)

    Gross, B. H.; Kreutz, K. J.; Osterberg, E. C.; McConnell, J. R.; Handley, M.; Wake, C. P.; Yalcin, K.

    2012-08-01

    Trends and sources of lead (Pb) aerosol pollution in the North Pacific rim of North America from 1850 to 2001 are investigated using a high-resolution (subannual to annual) ice core record recovered from Eclipse Icefield (3017 masl; St. Elias Mountains, Canada). Beginning in the early 1940s, increasing Pb concentration at Eclipse Icefield occurs coevally with anthropogenic Pb deposition in central Greenland, suggesting that North American Pb pollution may have been in part or wholly responsible in both regions. Isotopic ratios (208Pb/207Pb and 206Pb/207Pb) from 1970 to 2001 confirm that a portion of the Pb deposited at Eclipse Icefield is anthropogenic, and that it represents a variable mixture of East Asian (Chinese and Japanese) emissions transported eastward across the Pacific Ocean and a North American component resulting from transient meridional atmospheric flow. Based on comparison with source material Pb isotope ratios, Chinese and North American coal combustion have likely been the primary sources of Eclipse Icefield Pb over the 1970-2001 time period. The Eclipse Icefield Pb isotope composition also implies that the North Pacific mid-troposphere is not directly impacted by transpolar atmospheric flow from Europe. Annually averaged Pb concentrations in the Eclipse Icefield ice core record show no long-term trend during 1970-2001; however, increasing208Pb/207Pb and decreasing 206Pb/207Pb ratios reflect the progressive East Asian industrialization and increase in Asian pollutant outflow. The post-1970 decrease in North American Pb emissions is likely necessary to explain the Eclipse Icefield Pb concentration time series. When compared with low (lichen) and high (Mt. Logan ice core) elevation Pb data, the Eclipse ice core record suggests a gradual increase in pollutant deposition and stronger trans-Pacific Asian contribution with rising elevation in the mountains of the North Pacific rim.

  14. A wearable 12-lead ECG acquisition system with fabric electrodes.

    Science.gov (United States)

    Haoshi Zhang; Lan Tian; Huiyang Lu; Ming Zhou; Haiqing Zou; Peng Fang; Fuan Yao; Guanglin Li

    2017-07-01

    Continuous electrocardiogram (ECG) monitoring is significant for prevention of heart disease and is becoming an important part of personal and family health care. In most of the existing wearable solutions, conventional metal sensors and corresponding chips are simply integrated into clothes and usually could only collect few leads of ECG signals that could not provide enough information for diagnosis of cardiac diseases such as arrhythmia and myocardial ischemia. In this study, a wearable 12-lead ECG acquisition system with fabric electrodes was developed and could simultaneously process 12 leads of ECG signals. By integrating the fabric electrodes into a T-shirt, the wearable system would provide a comfortable and convenient user interface for ECG recording. For comparison, the proposed fabric electrode and the gelled traditional metal electrodes were used to collect ECG signals on a subject, respectively. The approximate entropy (ApEn) of ECG signals from both types of electrodes were calculated. The experimental results show that the fabric electrodes could achieve similar performance as the gelled metal electrodes. This preliminary work has demonstrated that the developed ECG system with fabric electrodes could be utilized for wearable health management and telemedicine applications.

  15. Gender Differences in Comparisons and Entitlement: Implications for Comparable Worth.

    Science.gov (United States)

    Major, Brenda

    1989-01-01

    Addresses the role of comparison processes in the persistence of the gender wage gap, its toleration by those disadvantaged by it, and resistance to comparable worth as a corrective strategy. Argues that gender segregation and undercompensation for women's jobs leads women to use different comparison standards when evaluating what they deserve.…

  16. Interactions of lead with sediments and meiofauna

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, D. (Queens Univ., Belfast); Maguire, C.

    1976-11-01

    Harpactacoid copepods and Turbellaria appear to be the most sensitive faunal groups in surface sand meiofauna when subjected to contamination by lead; in subsurface sand, nematodes are found to be the most sensitive group. Simple laboratory attempts to assess lead partitioning in littoral sand gave variable results and the problems and merits of such experimental approaches are discussed.

  17. Lead use and recycling at the INEL

    International Nuclear Information System (INIS)

    Losinski, S.J.; Thurmond, S.M.

    1995-08-01

    As part of DOE's efforts to develop a Department-wide management strategy for the use, reuse, and recycle of lead, DOE has requested that each site provide site-specific management and use practices for lead, specifically management and use information that responds to four specific questions of interest. This report provides the Idaho National Engineering Laboratory's response to those areas of interest

  18. The Time, Space and Matter of Leading

    DEFF Research Database (Denmark)

    Jørgensen, Kenneth Mølbjerg

    2018-01-01

    This paper develops an ethical framework of leadership learning from Hannah Arendt’s writing. The intention is to identify important principles of a framework of leadership leading that help empower actors to lead themselves and to engage, interact, influence and inspire others through...

  19. Diverse Neurological Manifestations of Lead Encephalopathy ...

    African Journals Online (AJOL)

    Three patients with lead encephalopathy due to industrial poisoning are presented. They all showed a wide spectrum of neurological manifestations, which mimic other neurological presentations. It is emphasised that lead poisoning still occurs in industry, despite efforts at prevention. S. Afr. Med. J., 48, 1721 (1974) ...

  20. Lead arthropathy: radiographic, CT and MRI findings

    International Nuclear Information System (INIS)

    Fernandes, Joao Luiz; Lopes Rocha, Arthemizio Antonio; Veloso Ayrimoraes Soares, Mayra; Lopes Viana, Sergio

    2007-01-01

    Lead arthropathy is a well-known complication of gunshot injuries with retained intra-articular bullets. Although several previous reports have discussed the radiological findings of this entity, computed tomography (CT) and magnetic resonance imaging (MRI) findings have never been described before in this setting. In this paper the authors review the imaging findings of 11 patients with lead arthropathy (1 of whom had clinical signs of lead poisoning as well), all of them studied by means of radiographs. In addition, non-enhanced CT scans were obtained in 3 patients and gadolinium-enhanced MRI in 1. Classic findings of intra-articular speckled lead deposits (occasionally with a ''lead arthrogram'' appearance), joint space narrowing and preserved bone density were found at radiographs in the great majority of cases. Furthermore, extension of intra-articular lead to adjacent tendon sheaths was observed in almost half of the patients, an observation rarely reported in the literature. CT scans and MRI, in their turn, were superior with regard to soft tissue abnormalities, accurately depicting joint effusion and the thickened synovium with lead particles embedded in it. Post-gadolinium MRI had the advantage of showing the enhancement pattern of the inflamed synovium and associated bone marrow edema pattern. Although it is not possible to establish the role of axial imaging in lead arthropathy from the small number of cases studied, this initial experience shows that both methods hold promise in this setting and may be useful, at least in selected cases. (orig.)