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Sample records for kerma ar em

  1. Product kerma in the air-area and radiation dose in dental radiodiagnosis; Produto kerma ar-area e dose efetiva em radiodiagnostico odontologico

    Costa, Alessandro Martins da, E-mail: amcosta@usp.br [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras. Dept. de Fisica

    2014-07-01

    The main purpose of patient dosimetry in diagnostic radiology is to determine dosimetric quantities for the establishment and use of reference levels and comparative risk assessment. In recent publications the use of the air kerma-area product, PKA, has been suggested in dental radiology, as this quantity is more closely related to risk. The aim of this study was to perform a preliminary survey of PKA and effective dose in different types of dental examinations. The future perspective is a large-scale survey for the establishment and use of diagnostic reference levels in dentistry in Brazil. (author)

  2. Product kerma air area and effective dose in dental radiology; Produto kerma no ar-area e dose efetiva em radiodiagnostico odontologico

    Mauro, Rodrigo A.P.; Souza, M. Daiane M.; Costa, Alessandro M. [Universidade de Sao Paulo (USP), Ribeirao Preto (USP), SP (Brazil). Faculdade de Filosofia Ciencias e Letras

    2016-07-01

    The main purpose of patient dosimetry in diagnostic radiology is to determine dosimetric quantities for the establishment and use of reference levels and comparative risk assessment. The use of the air kerma-area product, P{sub KA}, has been suggested in dental radiology, as this quantity is more closely related to risk. The aim of this study was to perform a preliminary survey of P{sub KA} and effective dose in different types of dental examinations. The future perspective is a large-scale survey for the establishment and use of diagnostic reference levels in dentistry in Brazil. (author)

  3. Product kerma air area and effective dose in dental radiology; Produto kerma no ar area e dose efetiva em radiodiagnostico odontologico

    Mauro, Rodrigo A.P.; Souza, Daiane M.; Costa, Alessandro M., E-mail: rodrigomauro@usp.br [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia Ciencias e Letras

    2016-07-01

    The main purpose of patient dosimetry in diagnostic radiology is to determine dosimetric quantities for the establishment and use of reference levels and comparative risk assessment. The use of the air kerma-area product, P{sub KA}, has been suggested in dental radiology, as this quantity is more closely related to risk. The aim of this study was to perform a preliminary survey of P{sub KA} and effective dose in different types of dental examinations. The future perspective is a large-scale survey for the establishment and use of diagnostic reference levels in dentistry in Brazil. (author)

  4. Kerma rate evaluation in the air in a room interventional cardiology; Avaliacao da taxa de Kerma no ar em uma sala de cardiologia intervencionista

    Real, Jessica V.; Luz, Renata M. da, E-mail: jessica.real@pucrs.br, E-mail: renata.luz@pucrs.br [Hospital Sao Lucas (HSL/PUCRS), Porto Alegre, RS (Brazil); Fröhlich, Bruna D.; Silva, Ana Maria Marques da, E-mail: bruna.frohlich@acad.pucrs.br, E-mail: ana.marques@pucrs.br [Pontificia Universidade Catolica do Rio Grande do Sul (PUCRS), Porto Alegre, RS (Brazil)

    2014-07-01

    In recent years, the number of interventional cardiology procedures is increasing. However, due to the long time of fluoroscopy in these procedures, care teams can receive high doses of radiation. The radiation scattered by the patient is not uniform, and their assessment is of utmost importance. This study aimed to estimate and map the kerma rate in the air at the time of the gonads, in an interventional cardiology room, seeking to optimize the dose absorbed by individuals occupationally exposed to ionizing radiation. For data collection, the room was divided into quadrants of 1m{sup 2}, totaling 40 collection points. The simulator was positioned so that its entry surface was located in the interventional reference point. Were chosen the conditions that simulate angiography and angioplasty procedures performed in the service. The data were obtained for height of 1 meter, gonad region. The results obtained for kerma rates in air, in quadrants, show that higher measured values was in the vicinity of the X-ray tube. Has been found that the medical staff are more exposed, because of its location during the procedure, around the table. The law of the inverse square distance of the farthest points of the X-ray tube were verified.

  5. Avaliação do kerma no ar na superfície de entrada e da qualidade da imagem em radiografias de tórax Evaluation of entrance surface air kerma rate and clinical images quality in chest radiography

    Angelo Bernardo Brasil de Souza

    2009-10-01

    Full Text Available OBJETIVO: Avaliar os fatores de técnica utilizados durante exames de tórax póstero-anterior em pacientes-padrão e correlacioná-los aos valores de kerma no ar na superfície de entrada e à qualidade das imagens clínicas. MATERIAIS E MÉTODOS: O estudo foi realizado em três hospitais do Rio de Janeiro, num total de cinco salas de raios X, com dez pacientes por sala. As imagens foram avaliadas pelos radiologistas dos serviços segundo o protocolo europeu. O kerma no ar na superfície de entrada foi estimado a partir da curva de rendimento do equipamento de raios X, que foi obtida utilizando câmara de ionização acoplada a um eletrômetro. Análise de variância foi realizada para verificar se a diferença entre os valores de kerma no ar na superfície de entrada é significativa. RESULTADOS: Os valores de kerma no ar na superfície de entrada variaram entre 0,05 e 0,26 mGy, com média 60% inferior ao nível de referência publicado na Portaria 453. Das imagens avaliadas, 98% atenderam acima de 65% dos critérios de qualidade. CONCLUSÃO: Para um padrão de qualidade da imagem, aceitável para o diagnóstico, verificou-se ampla variação do kerma no ar na superfície de entrada para pacientes-padrão. Isto demonstra a falta de padronização dos fatores de técnica e a existência de um potencial de redução do valor do kerma no ar na superfície de entrada.OBJECTIVE: To evaluate technical factors involved in posteroanterior chest radiography in standard patients, and correlating them with entrance surface air kerma rate and with the clinical images quality. MATERIALS AND METHODS: The present study was developed at three hospitals in Rio de Janeiro, Brazil, involving a total of five x-ray rooms, with ten patients per room. The images were evaluated by the radiologists of the institutions, in accordance with the European protocol. The estimation of surface entrance air kerma rate was based on the x-ray equipment output curve obtained with

  6. Image quality and volume computed tomography air kerma index (C{sub vol}) evaluation in Recife; Avaliacao da qualidade de imagem e do indice volumetrico de Kerma ar em tomografia computadorizada (C{sub vol}) em Recife

    Andrade, Marcos Ely Almeida

    2008-07-01

    The Computed Tomography (CT) is an important diagnostic imaging method, widely used. However, in spite of all the advantages and technologic advances within the CT scanners, the tomographic procedures result in high absorbed doses to patients. The main objective of this work was to perform a dosimetric study of CT scanners located at Recife and to evaluate the image quality on CT examinations in these equipment. The volume CT air kerma index (C{sub VOL}) and air kerma length product (P{sub KL,CT}) were estimated. These values were calculated using normalized weighted air kerma indexes in CT standard dosimetry phantoms ({sub n}C{sub W}), supplied by ImPACT group for several CT scanners, and the scan parameters of routine head, routine chest and hi-resolution chest CT exams performed at 20 institutions. The irradiation parameters of 15 adult patients for each CT procedure were registered at six participating centres, at which the phantom from the American College of Radiology (ACR) CT accreditation protocol was used for the image quality measurements. For routine head exams, the C{sub VOL} values varied between 12 and 58 mGy (at the posterior fossa) and 15 to 58 mGy (at the cerebrum) and the P{sub KL,CT}, from 150 to 750 mGy{center_dot}cm. The C{sub VOL} values for routine chest procedures varied from 3 to 26 mGy and the P{sub KL,CT}, between 120 and 460 mGy{center_dot}cm. In relation to Hi-resolution chest exams, C{sub VOL} values were from 1.0 to 2.7 mGy and the P{sub KL,CT} values varied between 24 and 67 mGy{center_dot}cm. The image quality evaluations results showed that almost all scanners presented at least one inadequacy. One of the equipment presented faults at 70% of the tests. With regard to the image noise, only two scanners presented acceptable results. From these results, it is possible to conclude that the volume CT air kerma index values are lower than the European reference levels. However, the image quality of these CT scanners does not attend the

  7. Kerma in the air at entry surface in thorax pediatric examinations at public hospital in Parana, Brazil; Kerma no ar na superficie de entrada em exames pediatricos de torax em hospital publico no Parana, Brasil

    Santos, Amanda; Porto, Lorena; Bunick, Ana; Paschuk, Sergei; Denyak, Valeriy, E-mail: schelin@utfpr.edu.b [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil); Schelin, Hugo; Tilly, Joao, E-mail: joao.tilly@derax.com.b [DERAX Desenvolvimento Radiologico, Curitiba, PR (Brazil); Khoury, Helen, E-mail: hjkhoury@gmail.co [Universidade Federal de Pernambuco (DOIN/UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Dosimetria e Instrumentacao Nuclear; Ferreira, Jose [Universidade Estadual do Oeste do Parana (UNIOESTE), Cascavel, PR (Brazil)

    2011-07-01

    This work consisted in the evaluation of the entrance skin air kerma (ESAK) in pediatric chest x-ray examinations. A study of 186 exams in anterior-posterior, posterior-anterior and lateral projections was carried out for patients with ages ranging from 0 to 15 years. The ESAK was measured with the DoseCal software and Li-Fl thermoluminescent dosimeters. The results were compared with measurements done recently at the same place and with the reference dose values established by the European Community. It was observed that the optimization of the technique and the routine changes suggested in the previous study were not maintained. The charge (mAs) and the ESAK values found in the present study were much higher than the previous one, and the voltage (kVp) values found was lower. The results suggest that the implementation of the Quality Assurance Program could adequate these parameters to the established levels and keep the pediatric examinations more uniform. (author)

  8. Distribution of kerma rate in the air inside of hemodynamic room for typical projections of interventionist cardiology procedures; Distribuicao da taxa de kerma no ar em uma sala de hemodinamica para projecoes tipicas de procedimentos de cardiologia intervencionista

    Sanchez, Mirtha Elizabet Gamarra

    2008-07-01

    The evaluation of dose to physicians involved in Interventional Cardiology (IC) is an extreme important matter due to the high and non-uniform distribution of dose values. The radiation control during each procedure is complex and the reasons for the high exposures have many different causes. Many international recommendations have already been written aiming the radiation protection optimization in IC. In Brazil, there is not any special orientation for the protection of those occupational persons, nor a specific legislation. The purpose of this work is to evaluate the air kerma rate at critical anatomic regions of the occupationally exposed staff that carry out IC procedures, in representative incidences in order to give subsidies for individual monitoring procedures implementation and to give more information about their radiation protection. The air kerma rate has been measured in the often used condition in the two more common IC procedures namely angiography and coronary angioplasty, using an adult patient simulator irradiated under RAO, LAO and AP projections for fluoro and digital acquisition modes. The measurements have been made in 45 points around the examination table at 5 different representatives heights of: eyes lens, thorax, hands, gonads and knees. AP projection shows the smaller scattered radiation contributions and a more homogeneous exposure distribution. The digital acquisition mode gives air kerma rates about 4 times higher than fluoro mode for LAO projection in the position occupied by the interventionist doctor, the anesthetist and the nursing staff. The most critical anatomic regions are: knees and gonads (without protection). On the physician hands position, values as high as 5 mGy/h have been measured, which can overpass, depending on the number of procedures done, the individual occupational annual limit. Therefore, in IC it is necessary to implement additional protection tools, elaborate safety guides (based on international experiences

  9. Bilateral IFBA/IRD comparison in diagnostic radiology: Air kerma in RQR series; Comparação bilateral IFBA/IRD em radiologia diagnóstica - Kerma no ar nas qualidades RQR

    Macedo, E.M.; Navarro, M.V.T.; Garcia, I.F.M.; Ferreira, M.J., E-mail: ematosmacedo@gmail.com [Instituto Federal da Bahia (Labprosaud/IFBA), Savador, BA (Brazil). Lab. de Produtos para Saúde; Peixoto, J.G.P. [Instituto de Radioproteção e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2017-07-01

    Two interlaboratory comparisons were conducted, in 2016 and 2017, by the IRD and Labprosaud/IFBA calibration laboratories, creating subsidies to improve the quality and standardization of the calibration services performed by both. The comparisons were performed in terms of air kerma for RQR series radiation qualities, according IEC 61267. Substitution method was used, based on TRS 457 recommendations and Technical Protocol to Bilateral Comparison of Calibration Brazilian Network Laboratories in Diagnostic Radiology (2015). Results varying between 0.994 and 1.006 on first comparison, and between 0.986 and 1.009 on second one, were declared satisfactory. (author)

  10. Calculation of conversion factor of Kerma in the air for ambient dose equivalent in radiotherapy; Calculo dos fatores de conversao de Kerma no ar para equivalente de dose ambiental em radioterapia

    Lima, Marco Antonio Frota

    2000-03-01

    This work aims to estimate the average conversion factor of Kerma in air to H {sup *} (10) using photon beams coming from clinic linear accelerators, transmitted through concrete walls of a radiotherapic treatment room. The transmitted photon spectra by both 1 meter and 2 meters concrete walls, in an area of 40 x 40 cm{sup 2}, were calculated when the primary beam impart in an angle of 0 deg. The (secondary) photon beams transmitted respectively by 0,5 meter, 1,0 meter, 1,0 meter and 2,0 meter concrete walls, after they scattered by an angle of 90 deg in a cylindric phantom inside the room, were also determined. Generally, 50 millions of histories were computed for each simulation made for the primary beam. For the 90 deg spread, the number of histories was 100 millions. The computational code used on this work was the MCNP4B. The most common clinic accelerators used on radiotheraphic treatments were used on this work CLINAC-4, CLINAC-6, CLINAC-18 and CLINAC-2500. From the spectra analysis obtained in this work, it was possible to dispose the conversion factor for realistic beams found in radiotherapeutic establishment. (author)

  11. Uncertainty evaluation of the kerma in the air, related to the active volume in the ionization chamber of concentric cylinders, by Monte Carlo simulation; Avaliacao de incerteza no kerma no ar, em relacao ao volume ativo da camara de ionizacao de cilindros concentricos, por simulacao de Monte Carlo

    Lo Bianco, A.S.; Oliveira, H.P.S.; Peixoto, J.G.P., E-mail: abianco@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Lab. Nacional de Metrologia das Radiacoes Ionizantes (LNMRI)

    2009-07-01

    To implant the primary standard of the magnitude kerma in the air for X-ray between 10 - 50 keV, the National Metrology Laboratory of Ionizing Radiations (LNMRI) must evaluate all the uncertainties of measurement related with Victtoren chamber. So, it was evaluated the uncertainty of the kerma in the air consequent of the inaccuracy in the active volume of the chamber using the calculation of Monte Carlo as a tool through the Penelope software

  12. Calculation of the correction factors for the primary standard of kerma in the air at the LNMRI-IRD, Rio de Janeiro, Brazil; Calculo de fatores de correcao para o padrao primario em kerma no ar do LNMRI-IRD, Rio de Janeiro, Brasil

    Silva, Cosme Norival Mello da, E-mail: cosme@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Lab. Nacional de Metrologia das Radiacoes Ionizantes (LNMRI)

    2009-07-01

    In order to determine the primary standardization in terms of kerma in the air, a graphite ionization chamber is used for calculation some correction factors. A program was elaborated, using the Monte Carlo Penelope for simulate the CC01-110 at the LNMRI/IRD, Rio de Janeiro, Brazil

  13. Construction of a laboratory for the implantation of primary standardization of the magnitude kerma in the air for the X-ray beams used in mammography; Construcao de um laboratorio para a implantacao da padronizacao primaria da grandeza kerma no ar para os feixes de raios X empregados em mamografia

    Cardozo, W.L.; Magalhes, L.A.A.M.F.; Peixoto, J.G.P., E-mail: wagnerlc@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Lab. Nacional de Metrologia das Radiacoes Ionizantes (LNMRI)

    2009-07-01

    Aiming to diminish the uncertainty in each phase of the metrological chain, and the uncertainty in dosimetry processed at the X-ray beam applied in the mammography, is necessary that the LNMRI/IRD to develop a reference primary standard for the absolute form to the magnitude kerma in the air

  14. Measurement of conversion coefficients between air Kerma and personal dose equivalent and backscatter factors for diagnostic X-ray beams; Determinacao experimental dos coeficientes de conversao de Kerma no ar para o equivalente de dose pessoal, Hp(d), e fatores de retroespalhamento em feixes de raios-x diagnostico

    Rosado, Paulo Henrique Goncalves

    2008-07-01

    Two sets of quantities are import in radiological protection: the protection and operational quantities. Both sets can be related to basic physical quantities such as kerma through conversion coefficients. For diagnostic x-ray beams the conversion coefficients and backscatter factors have not been determined yet, those parameters are need for calibrating dosimeters that will be used to determine the personal dose equivalent or the entrance skin dose. Conversion coefficients between air kerma and personal dose equivalent and backscatter factors were experimentally determined for the diagnostic x-ray qualities RQR and RQA recommended by the International Electrotechnical Commission (IEC). The air kerma in the phantom and the mean energy of the spectrum were measured for such purpose. Harshaw LiF-100H thermoluminescent dosemeters (TLD) were used for measurements after being calibrated against an 180 cm{sup 3} Radcal Corporation ionization chamber traceable to a reference laboratory. A 300 mm x 300 mm x 150 mm polymethylmethacrylate (PMMA) slab phantom was used for deep-dose measurements. Tl dosemeters were placed in the central axis of the x-ray beam at 5, 10, 15, 25 and 35 mm depth in the phantom upstream the beam direction Another required parameter for determining the conversion coefficients from was the mean energy of the x-ray spectrum. The spectroscopy of x-ray beams was done with a CdTe semiconductor detector that was calibrated with {sup 133} Ba, {sup 241} Am and {sup 57} Co radiation sources. Measurements of the x-ray spectra were carried out for all RQR and RQA IEC qualities. Corrections due to the detector intrinsic efficiency, total energy absorption, escape fraction of the characteristic x-rays, Compton effect and attenuation in the detector were done aiming an the accurate determination of the mean energy. Measured x-ray spectra were corrected with the stripping method by using these response functions. The typical combined standard uncertainties of

  15. Evaluation of kerma rate in radioactive waste disposal; Avaliacao da taxa de kerma em deposito de rejeitos radioativos

    Rosa, Rodolfo O.; Silva, Joao C.P.; Santos, Joao R. dos, E-mail: oliveira@ien.gov.br, E-mail: jcarlos@ien.gov.br, E-mail: regis@ien.gov.br [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2014-07-01

    This study aims to assess the progression of kerma rate levels in the air due to the increase of collection, storing and storage of radioactive waste in the new building (after expansion) of the radioactive waste disposal (RWD) of the Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Brazil. This review is carried out every six months at IEN with thermoluminescent dosimeter lithium fluoride LiF: Mg, Cu, P (TLD-100H). Here are the average values of kerma rate for the period 2008- 2012. In this context, the methodology used for selection and choices of detectors used in dosimeters is presented. The detectors were chosen through homogeneity criteria of the pack, standardization factor and coefficient of variation (CV%). The monitoring points and the exposure time of the detectors are chosen considering various factors, including the rate of occupation and indoor and outdoor positions to RWD. These evaluations showed that the contribution of the new waste disposal in increasing kerma rate of IEN, has proved to be insignificant, that is, the presence of RWD does not contribute to increased environmental kerma rate in the region around this installation.

  16. Air kerma standardization for diagnostic radiology, and requirements proposal for calibration laboratories; Padronizacao da grandeza Kerma no ar para radiodiagnostico e proposta de requisitos para laboratorios de calibracao

    Ramos, Manoel Mattos Oliveira

    2009-07-01

    The demand for calibration services and quality control in diagnostic radiology has grown in the country since the publication of the governmental regulation 453, issued by the Ministry of Health in 1998. At that time, to produce results facing the new legislation, many laboratories used different standards and radiation qualities, some of which could be inadequate. The international standards neither supplied consistent radiation qualities and standardization for the different types of equipment available. This situation changed with the publication of the new edition of the IEC 61267 standard, published in 2005. A metrology network was created, but it is not yet accredited by the accreditation organism of the country, INMETRO. The objective of this work was to implement the standardization of the air kerma for the un attenuated qualities (RQR) of IEC 61267, and to develop a requirement proposal for instruments calibration laboratories. Results of interlaboratory comparisons demonstrate that the quantity is standardized and internationally traceable. A laboratory requirement proposal was finalized and it shall be submitted to INMETRO to be used as auxiliary normative document in laboratory accreditation. (author)

  17. Product estimate of air kerma-area and the air kerma in the input surface of the skin of pediatric patients undergoing chest X-ray; Estimativa do produto kerma ar-area e do kerma ar na superficie de entrada da pele de pacientes pediatricos submetidos a radiografia de torax

    Villa-Chan, Beatriz; Carvalho, Aline; Andrade, Marcos Ely A.; Barros, Vinicius S.M. de; Khoury, Helen J., E-mail: beatrizvillachan@gmail.com, E-mail: alinecx90@gmail.com, E-mail: marcos.ely@gmail.com, E-mail: vsmdbarros@gmail.com, E-mail: hjkhoury@gmail.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear

    2014-07-01

    The aim of this paper is to evaluate the entrance air kerma (Ka,e) and the product air kerma-area (Pka) for chest examinations performed with pediatric patients in a large public hospital of Recife. For this study 89 examinations of patient with ages from zero to 10 years old were evaluated. The results showed that the mean Ka,e values, for patients of 0-1 years old, 1-5 years old and 5-10 years old, were, respectively, 100 mGy, 120 mGy and 100 mGy. The Pka values for newborn patients range from 11,9 to 58,4 mGy.cm{sup 2}, for patients with 1 to 5 years old range from 17 to 192 mGy.cm{sup 2}, and from 30,4 to 136,2 mGy.cm{sup 2} for patients with ages from 5 to 10 years old. The differences in the Pka values are due the different dimensions of the radiation field. For the results its possible to conclude that the Pka values are high, in special for patients with ages from 1 to 5 years old, indicating that the collimation of the radiation field is not adequate. (author)

  18. Rate air Kerma entrance skin of patients undergoing hemodynamic procedures in the State of Santa Catarina, Brazil; Taxa de Kerma no ar na entrada da pele de pacientes submetidos a procedimentos hemodinamicos no Estado de Santa Catarina

    Queiroz, Carlos Eduardo B.; Grechi, Bruna E.; Hahn, Tiago T.; Dalcin, Rodrigo C.; Augusto, Israel J.; Bolzan, Vagner; Jahn, Tiago R.; Gerber Junior, Walmoli, E-mail: brasilrad@brasilrad.com.br [Brasilrad - Consultoria em Radioprotecao, Florianopolis, SC (Brazil)

    2013-12-15

    This paper presents the results of the measured values of the skin entrance Air Kerma Rate in patients submitted to hemodynamic procedures, in the State of Santa Catarina, using as limit values set by the International Basic Safety Standards Guide, published by the International Atomic Energy Agency (IAEA ), and comparing them to the limits established by the Ordinance No. 453/1998. Tests were performed to measure the rate of Kerma skin entrance in 13 hemodynamic equipment in 10 hospitals in the state of Santa Catarina, between January 2011 and December 2012, in hemodynamic operated through fluoroscopy mode. Among the evaluated equipment, 77% disagree with the limits established in the International Basic Safety Standards, however, if compared the values of the Air Kerma rate obtained with the limit established by Ordinance No. 453, 100% of the devices are approved. The results obtained in this paper suggest the need for revision of the Ordinance No. 453/1998, by the regulatory agencies. (author)

  19. Microbiologia do ar : monitorização do ar em ambiente hospitalar

    Santos, Ana Carina Marques dos

    2008-01-01

    O complexo ambiente hospitalar requer atenção especial, para assegurar uma saudável qualidade do ar interior, protegendo assim os profissionais de saúde e utentes de infecções nosocomiais e de doenças ocupacionais. Embora seja amplamente reconhecido que a contaminação de um bloco operatório seja a principal responsável pela complicação de uma cirurgia, em Portugal, estudos sobre microbiologia do ar a nível hospitalar são escassos. O objectivo deste estudo é investigar a vari...

  20. Comparison of entry kerma in the skin with the variation of automatic exposure control in mammography;Comparacao do kerma de entrada na pele com a variacao do controle automatico de exposicao em exames mamograficos

    Macao Junior, J.L. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil); Mecca, F.A. [Instituto Nacional de Cancer (INCa), Rio de Janeiro, RJ (Brazil); Gomes, B.C. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2009-07-01

    The purpose of this work was to analyze the entry kerma values in the skin in comparison with the automatic exposure control tests. To achieve that, 44 mammographies were evaluatecl in the city of Rio de Janeiro. The reference values adopted were taken from the current Brazilian legislation, 'Portaria no. 453/98 do Ministerio da Saude', where the reference entry kerma value in the skin corresponds to 10 mGy and the maximum variation accepted to the automatic exposure control test corresponds to 30 optic unities. It was observed that 46.7% of the analyzecl mammographies presented entry kerma values in the skin above the reference level established, whereas the automatic exposition control for these same mammographies was within the acceptability parameters. (author)

  1. Evaluation of skin entry kerma in radiological examinations at the Hospital de Clinicas, Parana, Brazil; Avaliacao de kerma de entrada na pele em exames radiologicos no Hospital de Clinicas do Parana, Brasil

    Porto, Lorena E.; Schelin, Hugo R.; Santos, Amanda C. dos; Bunick, Ana Paula; Paschuk, Sergei; Denyak, Valeriy [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil); Tilly Junior, Joao G. [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Hospital de Clinicas; Khoury, Helen J., E-mail: khoury@ufpe.b [Universidade Federal de Pernambuco (UFPE/DEN), Recife, PE (Brazil). Dept. de Energia Nuclear

    2011-10-26

    This paper evaluates the skin entry dose of pediatric and adults patients when submitted to radiological examinations at the Hospital de Clinicas do Parana, Brazil, as part integrate of the data assessment of International Atomic Energy Agency (IAEA) for Latin America. It was performed measurements of dose for evaluation of skin entry kerma in pediatric patients in thorax AP/PA examinations, adults of thorax in AP/PA, cranio caudal mammography and median lateral and patients of computerized tomography in examination of head, thorax and abdomen. The obtained data demonstrate the necessity of verification of diagnostic analysis standards. The great value amplitudes demonstrate the incompatibility of examination executions with those recommended by the literature. The dose values presented partially inside the range recommended and the other over the expected for the due examination when compared with the literature

  2. Permeabilidade ao ar em Latossolo Vermelho sob diferentes sistemas de manejo

    Sueli Rodrigues

    2011-02-01

    Full Text Available A permeabilidade ao ar pode ser utilizada para avaliar alterações que ocorrem na estrutura do solo em virtude da adoção de diferentes sistemas de manejo. Este estudo testou a hipótese de que o menor revolvimento do solo sob sistema plantio direto resulta na formação de poros mais contínuos e melhor condição de aeração no solo. O objetivo deste trabalho foi avaliar, por meio da permeabilidade ao ar (Ka, da porosidade de aeração (εa e dos índices de continuidade de poros (K1 e N, a aeração em um Latossolo Vermelho distrófico sob preparo convencional (PC e sistema plantio direto (SPD. Oitenta amostras de solo (2 tratamentos x 2 profundidades x 20 repetições com estrutura indeformada foram coletadas de cada sistema de manejo do solo nas profundidades de 0-0,10 e 0,10-0,20 m em área experimental do Instituto Agronômico do Paraná, no município de Ponta Grossa, Paraná. Depois de saturadas e equilibradas em seis potenciais mátricos (-2, -6, -10, -30, -70 e -100 kPa, determinou-se a permeabilidade ao ar e a porosidade de aeração em cada potencial. Também foram determinados a densidade do solo, a densidade de partícula, o carbono orgânico e a porosidade. A densidade do solo não consistiu em fator limitante, ficando abaixo do limite crítico para solos argilosos nos dois sistemas. No SPD, o maior volume de microporos resultou em maior retenção de água no intervalo de umidade avaliado (-2 a -100 kPa e em maior volume de poros bloqueados para o fluxo de ar (εb, ou seja, redução de Ka. Na profundidade avaliada (00,20 m, os índices de continuidade de poros (K1 e N revelaram que o PC apresentou poros mais contínuos do que o SPD, contradizendo a hipótese testada.

  3. CONCENTRAÇÃO E DIMENSÃO DE PARTICULADOS DISPERSOS NO AR EM AMBIENTES DE MARCENARIAS

    BARBOSA, R. P.

    2014-01-01

    BARBOSA, Renan Pereira. CONCENTRAÇÃO E DIMENSÃO DE PARTICULADOS DISPERSOS NO AR EM AMBIENTES DE MARCENARIAS. 2014. Dissertação (Mestrado em Ciências Florestais) Universidade Federal do Espírito Santo, Jerônimo Monteiro-ES. Orientador: Prof. Dr. Nilton César Fiedler. Coorientador: Prof. Dr. José Reinaldo Moreira da Silva. Objetivou-se com esta pesquisa caracterizar as partículas de madeira de Eucalyptus spp. suspensas no ar em marcenarias. A coleta de dados foi realizada por meio de uma a...

  4. Macrófitas aquáticas em tratamento de águas contaminadas por arsênio

    Santos, Edilayne Cristina

    2008-01-01

    A poluição das águas por arsênio, e compostos: orgânicos, fosfatados e nitrogenados é um dos maiores problemas do mundo moderno. A fitorremediação tem sido utilizada, na busca de espécies vegetais com potencial para a remoção desses compostos. Nesse intuito, espécies de macrófitas foram colocadas em presença de arsênio em meio aquoso nutritivo, a fim de estudar a absorção do arsênio pelas mesmas e a sua cinética. A análise do crescimento e da produção de biomassa, em curto intervalo de tempo,...

  5. Transporte de CO2 em meio aquoso a partir da interface agua-ar

    Euler Martins Lage

    2002-01-01

    Resumo: Neste trabalho estudou-se o transporte de CO2 através da interface água-ar e a sua difusão na água, a partir de experimentos simples e de baixo custo, em escala laboratorial. Para este estudo foram utilizadas soluções aquosas de diferentes salinidades (0, 10, 30 e 65 g/kg), a diferentes temperaturas (25 e 40 °C). Para a determinação da concentração de CO2 dissolvido, adicionou-se indicadores ácido-base. Foram obtidas imagens das soluções a diferentes tempos após o início da difusão. A...

  6. Estudo exploratorio da qualidade do ar em escolas de educacao basica, Coimbra, Portugal

    Ana Maria Conceicao Ferreira

    2013-12-01

    Full Text Available OBJETIVO : Analisar a qualidade do ar em escolas de educação básica e suas condições estruturais e funcionais. MÉTODOS : Foi avaliada a qualidade do ar de 51 escolas (81 salas de aula de educação básica da cidade de Coimbra, Portugal, tanto na parte interior das salas como na exterior, durante as quatro estações do ano, de 2010 a 2011. Foram avaliadas a temperatura (Tº, umidade relativa (Hr, concentrações de monóxido de carbono (CO, dióxido de carbono (CO 2 , ozona (O 3 , dióxido de nitrogênio (NO 2 , dióxido de enxofre (SO 2 , compostos orgânicos voláteis (COV, formaldeído e material particulado (PM 10 , de novembro de 2010 a fevereiro de 2011 (outono/inverno e de março de 2011 a junho de 2011 (primavera/verão. Procedeu-se ao preenchimento de uma grelha de caracterização das condições estruturais e funcionais das escolas. Aplicaram-se os testes estatísticos t- Student para amostras emparelhadas e o teste t de Wilcoxon. RESULTADOS : Em 47 escolas, as concentrações médias de CO 2 encontravam-se acima da concentração máxima de referência (984 ppm mencionada na legislação portuguesa. Os valores máximos de concentração encontrados no interior das salas foram críticos, principalmente no outono/inverno (5.320 ppm. As concentrações médias de COV e de PM 10 no interior ultrapassaram a concentração máxima de referência legislada em algumas escolas. Não foram detetados valores relevantes (risco de CO, formaldeído, NO 2 , SO 2 e O 3 . CONCLUSÕES : Houve maior concentração de poluentes no interior das salas, comparativamente com o exterior. A inadequada ventilação está associada à elevada concentração de CO 2 nas salas de aula.

  7. Calculation of neutron kerma in tissues

    Vega C, H.R.; Manzanares A, E.

    2004-01-01

    Neutron kerma of normal and tumor tissues has been calculated using the tissues elemental concentration. A program developed in Math cad contains the kerma factors of C, H, O, N, Na, Mg, P, S, Cl, K, etc. that are in normal and tumor human tissues. Having the elemental composition of any human tissue the neutron kerma can be calculated. The program was tested using the elemental composition of tumor tissues such as sarcoma, melanoma, carcinoma and adenoid cystic, also neutron kerma for adipose and muscle tissue for normal adult was calculated. The results are in agreement with those published in literature. The neutron kerma for water was also calculated because in some dosimetric calculations water is used to describe normal and tumor tissues. From this comparison was found that at larger energies kerma factors are approximately the same, but energies less than 100 eV the differences are large. (Author)

  8. Qualidade da cama e do ar em diferentes condições de alojamento de frangos de corte

    Thayla Morandi Ridolfi de Carvalho

    2011-04-01

    Full Text Available O objetivo deste trabalho foi avaliar as condições iniciais de alojamento de aves, de um dia de idade, em termos da qualidade da cama de frango reutilizada e do ar, em aviários comerciais de produção com diferentes sistemas de ventilação mínima e tipologia, por meio de análise geoestatística. O experimento foi realizado em quatro aviários: Blue House I (T1 e Blue House II (T2, Dark House (T3 e Convencional (T4. As variáveis analisadas foram: pH, umidade, temperatura superficial e concentração de amônia, tendo-se coletado as amostras na altura dos frangos, em 80 pontos equidistantes no interior do pinteiro. A análise geoestatística auxiliou a identificação de pontos críticos no controle dos ambientes estudados. O manejo da ventilação mínima não é suficiente para garantir a qualidade do ar nos pinteiros. A cama reutilizada de casca de café e arroz (T1 e T2 apresenta melhor qualidade do que a cama reutilizada de maravalha fina (T3 e T4. O sistema de ventilação mínima, em T2 e T4, é o mais eficiente quanto à renovação do ar nos pinteiros.

  9. Secondary charged particle spectra and kerma calculations

    Coyne, J.J.; Gerstenberg, H.M.; Hennen, L.A.

    1985-01-01

    The calculation of kerma factors from known cross sections is not as simple as is often implied. The kerma factors are strongly influenced by the reaction mechanism assumed. An important example of this dependence on the reaction mechanism is the contribution of the 12 C(n,n')3α reaction to the total kerma in carbon. First, a short review will be given of the ENDF/B-V carbon cross sections which were used in the calculation of carbon kerma factors. Using the reaction channels implied in the ENDF/B-V evaluation, the contribution of various reactions to the total kerma factors in carbon will be given. A detailed analysis of the reaction mechanisms which could contribute to the (n,n')3α reaction in carbon has been carried out. First their contribution to kerma, independent of cross section, will be calculated and then the initial spectra of alpha particles produced by the various reaction mechanisms will be given. A discussion of possible ways of experimentally distinguishing the reaction mechanisms will be made by comparing their different initial spectra and their variation in kerma with neutron energy. Finally, the event-size spectra for tissue-equivalent proportional counters will be presented, giving only the contributions from the (n,n')3α reaction and its various possible reaction channels. 3 refs., 11 figs., 4 tabs

  10. KERMA ratios in pediatric CT dosimetry

    Huda, Walter; Ogden, Kent M.; Lavallee, Robert L.; Roskopf, Marsha L.; Scalzetti, Ernest M.

    2012-01-01

    Patient organ doses may be estimated from CTDI values. More accurate estimates may be obtained by measuring KERMA (Kinetic Energy Released in Matter) in anthropomorphic phantoms and referencing these values to free-in-air X-ray intensity. To measure KERMA ratios (R K ) in pediatric phantoms at CT. CT scans produce an air KERMA K in a phantom and an air KERMA K CT at isocenter. KERMA ratios (R K ) are defined as (K/K CT ), measured using TLD chips in phantoms representing newborns to 10-year-olds. R K in the newborn is approximately constant. For the other phantoms, there is a peak R K value in the neck. The median R K values for the GE scanner at 120 kV were 0.92, 0.83, 0.77 and 0.76 for newborns, 1-year-olds, 5-year-olds and 10-year-olds, respectively. Organ R K values were 0.91 ± 0.04, 0.84 ± 0.07, 0.74 ± 0.09 and 0.72 ± 0.10 in newborns, 1-year-olds, 5-year-olds and 10-year-olds, respectively. At 120 kV, a Siemens Sensation 16 scanner had R K values 5% higher than those of the GE LightSpeed Ultra. KERMA ratios may be combined with air KERMA measurements at the isocenter to estimate organ doses in pediatric CT patients. (orig.)

  11. Efeitos Tóxicos de Arsênio em Eisenia Andrei em Exposição a Solos do Entorno de Minerações de Ouro

    Rodrigo Henrique Alves

    2015-06-01

    Full Text Available Os produtos das atividades de mineração têm grande relevância econômica no Estado de Minas Gerais, Brasil. No entanto, seus inúmeros danos à biota, incluindo a fauna edáfica, resultam na necessidade de recuperação e biomonitoramento dessas áreas e do seu entorno. Considerando a importância ecológica e o potencial bioindicador das minhocas, o objetivo deste estudo foi avaliar a toxicidade de arsênio presente em solos do entorno de minerações de ouro, nas bacias dos rios Doce e São Francisco, a oligoquetas da espécie Eisenia andrei Bouché. Amostras de solos dessas áreas foram caracterizadas em relação às suas propriedades físicas e químicas, incluindo os metais Fe, Al, Cu, Ni, Zn e Mn e do metaloide As; com elas, foram conduzidos bioensaios, que avaliaram a sobrevivência, reprodução e variação da biomassa dos organismos. Também foram realizados testes de sensibilidade dessa espécie ao As adicionado a solo artificial tropical e em solo natural. Houve evidente efeito tóxico sobre a reprodução dessa espécie, que esteve altamente correlacionado com as concentrações de As nas amostras (r = -0,80. Amostras de solos naturais de locais avaliados nas duas áreas apresentaram concentrações de As acima do limite estipulado pela Resolução Conama nº 420 de 2009, chegando a 2.388,2 mg kg-1. A CL50 do As em solo artificial tropical (207,4 mg kg-1 foi seis vezes menor que a do solo natural (1.248,1 mg kg-1. A menor biodisponibilidade do As nos solos naturais foi atribuída a sua associação com o minério de Fe presente nas amostras. Concluiu-se que os solos do entorno de áreas de mineração causaram toxicidade crônica a E. andrei, em termos de sua reprodução, o que demonstrou o potencial de danos dessas atividades sobre a fauna edáfica dessas áreas. O estudo também forneceu informações ecotoxicológicas que podem ser úteis em avaliações de risco ambiental em solos tropicais.

  12. Kerma factors in interaction of neutrons with boron carbide

    Bondarenko, I.M.

    1979-01-01

    Heat generation in neutron interactions with boron carbide B 10 ; B 11 and 12 C is calculated. Kerma-factors (kerma-kinetic energy released in materials) were calculated for neutron energies between 10 -4 eV and 15 MeV. No major simplifying assumptions are introduced, and the accuracy of the calculated kerma-factors depends only on availability and accuracy of the basic nuclear data. The ENDF/B-4 data and recent experimental information are used for the calculation of kerma-factors. Plots of these kerma-factors are presented in units of eVxb/atom and wtxsec/(cmxn) as a function of neutron energy

  13. Monitoramento de fungos no ar comparação da quantidade de elementos fúngicos viáveis em dois centros de Transplante de Células-Tronco Hematopoéticas (TCTH) em Porto Alegre

    Caroline Pellicioli Brun

    2011-01-01

    Infecções fúngicas invasivas têm emergido como causa de alta morbimortalidade entre pacientes com neoplasia hematológicas, principalmente os submetidos a transplante de células-tronco hematopoéticas (TCTH). Fungos estão onipresentes na natureza, logo, medidas com o objetivo de reduzir a carga fúngica em ambientes hospitalares têm sido preconizadas. No presente estudo, foi realizada coleta de fungos no ar em dois centros de referência em TCTH do sul do Brasil, que possuem instalações distintas...

  14. Neutron kerma factors, and water equivalence of some tissue substitutes

    Singh, V. P.; Badiger, N. M.; Vega C, H. R.

    2014-08-01

    The kerma factors and kerma relative to air and water of 24 compounds used as tissue substitutes were calculated for neutron energy from 2.53 x 10 -8 up to 29 MeV. The kerma ratio of the tissue substitutes relative to air and water were calculated by the ratio of kerma factors of the tissue substitute to air and water respectively. The water equivalence of the selected tissue substitutes was observed above neutron energies 100 eV. Kerma ratio relative to the air for Poly-vinylidene fluoride and Teflon are found to be nearest to unity in very low energy (up to 1 eV) and above 63 eV respectively. It was found that the natural rubber as a water equivalent tissue substitute compound. The results of the kerma factors in our investigation shows a very good agreement with those published in ICRU-44. We found that at higher neutron energies, the kerma factors and kerma ratios of the selected tissue substitute compounds are approximately same, but differences are large for energies below 100 eV. (Author)

  15. Kerma factors in interaction of neutrons with boron carbide

    Bondarenko, I.M.

    1986-03-01

    Heat generation in neutron interactions with boron carbide B 10 ; B 11 and 12 C is calculated. Kerma-factors (kerma-kinetic energy released in materials) were calculated for neutron energies between 10 -4 eV and 15 MeV. No major simplifying assumptions are introduced, and the accuracy of the calculated kerma-factors depends only on availability and accuracy of the basic nuclear data. The ENDF/B-4 data and recent experimental information are used for the calculation of kerma-factors. Plots of these kerma-factors are presented in units of eVxb/atom and wtxsec/(cmxn) as a function of neutron energy [fr

  16. Estudo de Caso de um Evento Extremo de Incursão de Ar Frio em Julho de 2013 sobre a Bacia Amazônica Brasileira

    Liviany Pereira Viana

    Full Text Available Resumo A bacia Amazônica está localizada na região tropical cujas características principais são os elevados valores de temperatura e umidade do ar. Entretanto, incursões de massa de ar frio e seco também adentram a região, como ocorreu em julho de 2013. Essa quarta onda de frio que atuou sobre o continente sul-americano ocasionou neve em cidades da região Sul, caracterizando uma intensa massa polar com deslocamento até a região Norte. O presente trabalho analisou o comportamento de variáveis meteorológicas com intuito de investigar a intensidade do efeito dessa friagem. Os dados empregados foram de observações e das reanálises disponíveis. A anomalia negativa da temperatura máxima em Rio Branco foi de 15,9 °C, em Manicoré de 6,7 °C e Manaus de 2,0 °C. Nesse evento, os valores mais expressivos ocorreram na temperatura máxima. Também destaca-se uma contribuição mensal nas taxas de precipitação, cujos valores foram maiores que 13,0 mm.dia-1. Desse modo, conclui-se que, o evento de julho de 2013 foi um caso de intensa friagem devido deslocar-se até a região central da Amazônia e ocasionar quedas abruptas, principalmente, na temperatura máxima, favorecimento da precipitação nas regiões tropicais, bem como alterações na pressão em superfície, umidade e vento.

  17. Comparison of incident air kerma (ki) of common digital and analog radiology procedures in Kohgiluyeh and Boyer-Ahmad province

    Vafapour, Hassan; Salehi, Zaker

    2018-03-01

    Introduction: Although in many developed countries, Analog radiography (AR) is replaced with digital radiography (DR) but AR is still widely used in many countries included Iran. Therefore, dosimetrically assessment of delivered dose is very important to avoid unnecessary patient dose. Materials and Methods: In this study, all imaging centers in Kohgiluyeh and Boyer-Ahmad were selected. The initial information included the mean kVp and mAs used by the personnel to perform each radiological procedure were gathered through a questionnaire. Barracuda dosimeter was then used to measure Incident air kerma (ki). Data obtained from digital radiography (DR) and analogue radiography (AR) were then analyzed and compared to each other. Results: The mean incident air kerma (ki) for five radiological procedures (chest AP&Lat, Skull AP&Lat, Lumbar spine AP&Lat, Thoracic spine AP&Lat and Pelvis) in digital devices were 0.38&1.34, 2.1&1.94, 4.99&7.83, 4.18& 6.41 and 4.33 mGy and those for analogue devices were 0.7&1.28, 3.05&3.02, 7.25&9.9, 7.125&8.36 and 5.36 mGy, respectively. Discussion and Conclusion: The use of low kVp or high mAs is one of the reasons to increase the incident air kerma (ki) in analogue methods comparing to digital methods in all procedures except the chest (in Lateral view). Also the results, surprisingly, showed that in some of the analogue methods incident air kerma (ki) was less than digital methods which is most probably because of the auto-exposure conditions.

  18. Funcionalidade da oleoresina de páprica microencapsulada em goma-arábica e amido de arroz/gelatina.

    SANTOS, A.B.; FÁVARO-TRINDADE, C.S.; GROSSO, C.R.F.

    2006-01-01

    O objetivo deste trabalho foi avaliar a funcionalidade da oleoresina de páprica microencapsulada em goma-arábica e amido de arroz/gelatina, incorporada nos sistemas-modelo bolo e gel de gelatina. Avaliou-se a cor por meio de medida instrumental e aceitação sensorial por atributos de aparência e aceitação global. O pigmento encapsulado solubilizou-se, tingiu e se distribuiu uniformemente nos bolos, os quais apresentaram boa aceitação global. Nos géis, a goma apresentou desempenho superior ao a...

  19. Origem e distribuição do nervo toracodorsal em fetos de suínos da linhagem Pen Ar Lan

    Eleusa Marta Mendonça Tavares

    2011-11-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2012v25n1p111 Considerando a importância dos nervos que compõem o plexo braquial, objetivou-se estudar a origem e distribuição do nervo toracodorsal. Dessa forma, foram utilizados 30 fetos de suínos da linhagem Pen Ar Lan obtidos de abortos naturais em criatórios da região do Triângulo Mineiro. As peças foram preparadas por meio de injeções de soluções de Neoprene Látex “450” a 50% e de formaldeído a 10%, na artéria aorta descendente, e imersão nessa mesma solução por um período mínimo de 48 horas. As dissecações foram realizadas bilateralmente até atingir o plexo braquial, que surgiu dos ramos espinhais ventrais do sexto (C6, sétimo (C7 e oitavo (C8 nervos cervicais e do primeiro torácico (T1. Constatou-se que o nervo toracodorsal foi formado a partir de C8 em dois antímeros (3,33%; de T1 em 17 antímeros (28,33%; e de C8 e T1 em 41 antímeros (68,33 e que houve simetria quanto à sua origem em 23 animais (76,66%. Verificou-se, também, que o nervo toracodorsal enviou ramos em 100% dos casos para o músculo grande dorsal e em 36,66% para o redondo maior.

  20. Biomassa microbiana em amostras de solos secadas ao ar e reumedecidas Microbial biomass in air dried and rewetted soil samples

    Antônio Samarão Gonçalves

    2002-05-01

    Full Text Available O objetivo do trabalho foi avaliar a viabilidade do condicionamento de amostras como terra fina secada ao ar (TFSA por curto período, para a determinação do carbono da biomassa microbiana (BMS-C, pelo método da fumigaçãoextração, e verificar a respiração microbiana basal (RB do solo. O condicionamento como TFSA, procedendo-se à fumigação para a análise da BMS-C imediatamente ou 24 horas após o reumedecimento, proporcionou valores de BMS-C para os solos Podzólicos, Latossolo Vermelho-Amarelo álico e Orgânico, semelhantes aos valores dos seus controles. Os solos Glei Pouco Húmico e Vertissolo apresentaram valores de BMS-C similares aos do controle a partir de 24 horas de incubação; o solo Planossolo arenoso apresentou valores similares aos do controle com 72 horas, e a Rendizina, com 168 horas de incubação. Na maioria dos solos, a RB determinada na TFSA apresentou valores maiores do que os do tratamento-controle, quando avaliada imediatamente ou 24 horas após o reumedecimento a 60% da capacidade máxima de retenção de água, seguida de queda e manutenção em níveis semelhantes ao do controle nos períodos subseqüentes. O précondicionamento, de curta duração, como TFSA, é promissor para a determinação da BMS-C, quando níveis e períodos adequados de reumedecimento são adotados.The objective of this work was to evaluate the utilization of short term air dried soil samples in a determination of soil microbial biomass (SMB-C, by a fumigationextraction method, and soil microbial basal respiration (BR. Zero time or 24 hours rewetting incubation period before fumigation procedure gave values of SMB-C similar to those of the control for the Podzolic soils, Allic RedYellow Latosol and Organic soil. Low Humic Gley and Vertisol soils gave values of SMB-C similar to those of the control for periods of incubation equal or higher than 24 hours. Planosol (sandy soil and Rendzina soils gave values of SMB-C similar to the

  1. Gamma rays, Q-values, and kerma factors

    Muir, D.W.

    1976-02-01

    Formats have been proposed to allow the inclusion of evaluated neutron kerma factors in ENDF/B. The task of preparing evaluated kerma factors is analyzed in this report and is found to present numerous difficulties. Two alternative approaches to kerma-factor calculations are suggested, both of which require modifications of existing evaluations, notably through the inclusion of cross sections now missing for a number of neutron reactions, to allow postevaluation kerma-factor processing. The first approach requires neutron-induced charged-particle spectra, in addition to the missing reaction data. The second approach, which would not require the charged-particle spectra, would enforce energy conservation in the computed results

  2. Ars disyecta Ars disyecta

    Alejandra Castillo

    2012-07-01

    Full Text Available Bajo la nominación Ars Disyecta se busca exponer el vínculo entre artes visuales, feminismo y metamorfosis. Las prácticas artísticas feministas aquí presentadas se proponen perturbar el espacio metafórico heredado de la diferencia sexual (pensemos, por ejemplo, en las palabras engendramiento, matriz, vida, compenetración o invaginamiento. En este sentido, la nominación Ars disyecta pone en escena un conjunto de prácticas e intervenciones que intentan interrumpir la matriz de la diferencia, desestabilizando lo femenino desde aquellas figuras que se resisten a la lógica de la totalidad y de un tiempo propio. Buscando seguir la huella de un arte disyecto es que interrogaré en este ensayo aquellas autorías feministas que en el arte contemporáneo trafican con las huellas del contagio, la mutación y la alteridad.This article aims to present the relation between visual arts, feminism I and metamorphosis. The feminist artistic practices portrayed in this article attempt to question categories inherited from the metaphor of sexual difference such as engendering, matrix and life. From this perspective, Ars disyecta will establish a set of artistic practices and interventions that intend to interrupt the proper idea of «feminine difference». Following this line of argument, I will discuss in this article a few contemporary feminist works of art that could be defined by words such as contagious, mutation and otherness.

  3. Quantificação em escala de bancada do volume de ar em ligações prediais de água Measuring air volume in household pipes by means of a pilot scale study

    Ney Procópio Lopes

    2011-12-01

    Full Text Available A presente pesquisa em escala piloto, simulando trecho de uma rede interligada a um ramal predial, visou quantificar o volume de ar aferido pelos hidrômetros residenciais. Para tal fim, testaram-se ventosas, bloqueadores de ar e válvulas eliminadoras de ar. Sob condições normais de operação da rede, o volume de ar medido pelos hidrômetros é comparável ao encontrado na água natural, não justificando a instalação de equipamento de eliminação de ar de qualquer natureza. Todavia, logo após esvaziamento da rede interligada ao ramal, a sobremedição pode atingir até 21% em condições de pressão máxima na rede de distribuição (500 kPa. Por fim, verificou-se que a menor vazão afluente associa-se ao maior volume de ar aferido pelo hidrômetro. Dessa forma, é possível supor que os consumidores situados na menor faixa de consumo sejam os mais prejudicados pela situação de desabastecimento.The purpose of the present work is to evaluate the volume of air measured in domestic water supply pipe connections. Tests were performed to evaluate the efficiency and applicability of air reducing valves in domestic water supply connections. The results obtained under regular water supply conditions showed that the volume of air in the water measured by the hydrometers is comparable to the one found in natural waters. On the other hand, other tests, right after emptying the network connected to the domestic water supply pipe, revealed that the volume of water which gets to the gauged reservoir comprehends up to 21% of the total air-water volume recorded by the hydrometer for the experiments performed under pressure of 500 kPa.

  4. Origem e distribuição do nervo toracodorsal em fetos de suínos da linhagem Pen Ar Lan

    Mendonça Tavares, Eleusa Marta; França Ortega, Juliana; de Oliveira Honorato, Angelita das Graças; dos Santos, Lázaro Antônio; Ozanam Carneiro e Silva, Frederico

    2011-01-01

    http://dx.doi.org/10.5007/2175-7925.2012v25n1p111 Considerando a importância dos nervos que compõem o plexo braquial, objetivou-se estudar a origem e distribuição do nervo toracodorsal. Dessa forma, foram utilizados 30 fetos de suínos da linhagem Pen Ar Lan obtidos de abortos naturais em criatórios da região do Triângulo Mineiro. As peças foram preparadas por meio de injeções de soluções de Neoprene Látex “450” a 50% e de formaldeído a 10%, na artéria aorta descendente, e imersão nessa me...

  5. Uso da poeira e do ar como indicadores de contaminação ambiental em áreas circunvizinhas a uma fonte de emissão estacionária de chumbo

    Quiterio Simone Lorena

    2001-01-01

    Full Text Available Neste trabalho, determinou-se o nível de chumbo (Pb presente no ar em ambientes externos e na poeira doméstica de residências localizadas próximo a uma reformadora de baterias (RB. Uma das principais fontes de exposição ao Pb são empresas do setor de RB, que ainda utilizam processos e tecnologia obsoletos em instalações precárias. Na área externa à RB foram realizadas coletas em seis pontos localizados a aproximadamente 25m e a 500m da RB. Os resultados obtidos mostram que o limite para Pb no ar atmosférico (Pb-Ar de 1,5µg Pb.m-3 foi excedido em 50% das amostras coletadas, variando de 0,03 a 183,3µg Pb.m-3. As coletas nas dependências internas e externas das residências foram realizadas em seis pontos de quatorze residências localizadas a aproximadamente 25m, 50m e a 500m da RB. O limite de Pb na poeira doméstica (Pb-Pd de 1.500µg Pb.m-2 foi excedido em 44% das amostras coletadas, apresentando valores variáveis de 2,2 a 54.338,9µg Pb.m-2.

  6. Uso da poeira e do ar como indicadores de contaminação ambiental em áreas circunvizinhas a uma fonte de emissão estacionária de chumbo

    Simone Lorena Quiterio

    2001-06-01

    Full Text Available Neste trabalho, determinou-se o nível de chumbo (Pb presente no ar em ambientes externos e na poeira doméstica de residências localizadas próximo a uma reformadora de baterias (RB. Uma das principais fontes de exposição ao Pb são empresas do setor de RB, que ainda utilizam processos e tecnologia obsoletos em instalações precárias. Na área externa à RB foram realizadas coletas em seis pontos localizados a aproximadamente 25m e a 500m da RB. Os resultados obtidos mostram que o limite para Pb no ar atmosférico (Pb-Ar de 1,5µg Pb.m-3 foi excedido em 50% das amostras coletadas, variando de 0,03 a 183,3µg Pb.m-3. As coletas nas dependências internas e externas das residências foram realizadas em seis pontos de quatorze residências localizadas a aproximadamente 25m, 50m e a 500m da RB. O limite de Pb na poeira doméstica (Pb-Pd de 1.500µg Pb.m-2 foi excedido em 44% das amostras coletadas, apresentando valores variáveis de 2,2 a 54.338,9µg Pb.m-2.

  7. Evaluation of kerma in carbon and the carbon cross sections

    Axton, E.J.

    1992-02-01

    A preliminary simultaneous least squares fit to measurements of kerma in carbon, and carbon cross sections taken from the ENDF/B-V file was carried out. In the calculation the shapes of the total cross section and the various partial cross sections were rigid but their absolute values were allowed to float in the fit within the constraints of the ENDF/B-V uncertainties. The construction of the ENDF/B-V file imposed improbable shapes, particularly in the case of the (12)C(n,n'3(alpha)) reaction, which were incompatible with direct measurements of kerma and of the reaction cross sections. Consequently a new evaluation of the cross section data became necessary. Since the available time was limited the new evaluation concentrated particularly on those aspects of the ENDF/B-V carbon file which would have most impact on kerma calculations. Following the new evaluation of cross sections new tables of kerma factors were produced. Finally, the simultaneous least squares fit to measurements of kerma and the new cross section file was repeated

  8. Validação de simulações combinadas usando programas de simulação de energia do edifício e programas de transferência de calor, ar e umidade em componentes construtivos

    Costola, D.; Blocken, B.J.E.; Hensen, J.L.M.

    2011-01-01

    Desempenho higrotérmico dos edifícios tem sido estudado usando uma variedade de programas de computador, os quais consideram determinados domínios geométricos (exterior, envelope e interior) e físicos (calor, ar e umidade). Estes programas podem ser classificados em três principais grupos: programas

  9. Controle de fungos presentes no ar e em sementes de feijão durante armazenamento Control of fungi present in the air and bean seeds during storage

    Flávio M. Borém

    2006-09-01

    Full Text Available Objetivou-se, no presente trabalho, avaliar a eficácia de um equipamento redutor de inóculo (ERI na preservação da qualidade sanitária de sementes de feijão (Phaseolus vulgaris L. durante o armazenamento em estruturas herméticas com circulação de ar forçado. A presença de inóculo no ar foi monitorada a partir da exposição de placas de Petri com meio de cultura BDA salino, contando-se o número de unidades formadoras de colônias (UFC dos fungos Aspergillus spp. e Penicillium spp. As análises sanitárias das sementes foram realizada pelo método do papel de filtro (Blotter test, calculando-se o índice de ocorrência de Aspergillus spp. e Penicillium spp. Durante o período de armazenamento, houve um aumento na incidência de fungos nas sementes, independente da presença dos ERI. Nas amostragens realizadas na entrada da caixa com a presença dos ERI, não foram encontradas unidades formadoras de colônias. Com o aumento do fluxo de ar utilizado no sistema, notou-se que este efeito foi transferido para a saída da caixa. Nas condições especificadas, os ERI foram incapazes de controlar os fungos de armazenamento, Aspergillus spp e Penicillium spp, nas sementes de feijão, porém foram eficazes no controle dos seus esporos presentes no ar.The objective of the present work was to evaluate the efficiency of inoculum reducing equipment (IRE in the maintenance of quality of bean seeds during storage in hermetic structures with circulation of forced air. The inoculum's presence in the air was monitored by the exposition of Petri dishes with culture medium (saline BDA by counting the number of colonies units of Aspergillus and Penicillium. The quality analysis of seeds were performed by the blotter test. The occurrence index was calculated for Aspergillus spp and Penicillium spp. The fungal occurrence increased during the storage period, in spite of the IRE presence. Fungal colonies were not found in the air samples collected at the box

  10. Caracterização de MP2,5 e MP10 em Ar Ambiente de Estacionamento Fechado de Estabelecimento Comercial em Londrina-Paraná

    Jurandir Pereira Pinto

    2014-07-01

    Full Text Available Para investigar o perfil de concentração do MP em diferentes tamanhos aerodinâmicos presentes na atmosfera impactada pelo tráfego veicular leve, foram coletadas amostras de MP (MP2,5 e MP10 em um estacionamento comercial fechado onde circulam somente veículos leves em baixa velocidade. Foram realizadas quatro campanhas de amostragem em junho e dezembro de 2011 e 2012. O MP foi coletado utilizando ciclones (URG para MP2,5 e Low-Vol para MP10. Os filtros foram pesados em ultra balança analítica com precisão de 1,0 µg. As concentrações medias para MP2,5 e MP10 obtidas para a campanha de junho de 2011 foi de 41,9±10,1 µg m-3 e 56,4±12,6 µg m-3. Para a campanha de dezembro de 2011 obtiveram-se as concentrações médias 30,6±11,7 µg m-3 para o MP2,5 e para o MP10 52,8±12,7 µg m-3.  Em junho de 2012 o valor médio foi de 39,6 ± 9,1 µg m-3 para MP2,5 e 71,4 ± 10,9 µg m-3 de MP10. Em dezembro de 2012 as concentrações médias foram 21,3±7,2 µg m-3 para o MP2,5 e 49,9±10,6 µg m-3 para o MP10. As razões MP2,5 /MP10 com valores entre 0,42 e 0,75 mostram a variabilidade das emissões da frota veicular brasileira e da contribuição de emissões consideradas fugitivas.

  11. Quantificação de espécies de arsênio e antimônio presentes em material particulado atmosférico da Baía de Todos os Santos, Bahia

    Santos, Débora Correia dos

    2012-01-01

    A presença de metalóides tóxicos, como arsênio e antimônio, mesmo em baixas concentrações, presentes no material particulado atmosférico é motivo de preocupação em nível mundial nos últimos anos. Considerando esses aspectos, neste trabalho, foi desenvolvido um método para determinar as concentrações de As e Sb total e As(III) e Sb(III) em amostras de material particulado atmosférico do tipo PM10 em três locais diferentes em torno da cidade de Salvador (Bahia, Brasil). Os loc...

  12. Effective atomic number, electron density and kerma of gamma ...

    Abstract. An attempt has been made to estimate the effective atomic number, electron density (0.001 to 105 MeV) and kerma (0.001 to 20 MeV) of gamma radiation for a wide range of oxides of ... The lanthanide oxides find remarkable applications in the field of medicine, biology, nuclear engineering and space technology.

  13. Evaluation of kerma rate in radioactive waste disposal

    Rosa, Rodolfo O.; Silva, Joao C.P.; Santos, Joao R. dos

    2014-01-01

    This study aims to assess the progression of kerma rate levels in the air due to the increase of collection, storing and storage of radioactive waste in the new building (after expansion) of the radioactive waste disposal (RWD) of the Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Brazil. This review is carried out every six months at IEN with thermoluminescent dosimeter lithium fluoride LiF: Mg, Cu, P (TLD-100H). Here are the average values of kerma rate for the period 2008- 2012. In this context, the methodology used for selection and choices of detectors used in dosimeters is presented. The detectors were chosen through homogeneity criteria of the pack, standardization factor and coefficient of variation (CV%). The monitoring points and the exposure time of the detectors are chosen considering various factors, including the rate of occupation and indoor and outdoor positions to RWD. These evaluations showed that the contribution of the new waste disposal in increasing kerma rate of IEN, has proved to be insignificant, that is, the presence of RWD does not contribute to increased environmental kerma rate in the region around this installation

  14. Kerma determination in air on mamma by thermoluminescence

    Palacios P, L. L.; Rivera M, T.

    2009-10-01

    In this work the experimental results of the entrance exposition are shown and Kerma in air [mGy] in mamma obtained by irradiation of accreditation phantom of American College of Radiology (ACR). The irradiations were realized in a conventional mammography equipment of Hospital Juarez in Mexico; the technique used during the irradiations was of automatic exposition; the thickness for the phantom ACR obtained by the technique were of 4.2 and 4.5 cm; the kilo voltage pick was of 24 kV p , the time and the milli amperage per second variable. The measuring of Kerma in air was obtained with thermoluminescent dosemeters of solid state, of nano particles of zirconium dioxide prepared by the precipitation method. The dosemeters were homogenized previously in low energies of X-rays that are those used for mammography. The thermoluminescent dosemeters of ZrO 2 were calibrated by means of an ionization chamber for different expositions. The calibration curve is reported for the exposition and Kerma in air against thermoluminescent intensity obtained by reading of thermoluminescent dosemeters of ZrO 2 , as well as the technique employee for the Kerma determination in air and entrance exposition in mamma. (Author)

  15. Distribuição vertical e horizontal de temperaturas do ar em ambientes protegidos Vertical and horizontal distribution of air temperature in a plastic greenhouse

    Raquel A. Furlan

    2002-04-01

    Full Text Available Este trabalho foi realizado na área experimental do Departamento de Engenharia Rural da Escola Superior de Agricultura "Luiz de Queiroz", Piracicaba, SP, Brasil, em dois ambientes protegidos construídos no sentido leste-oeste, com área total de 112 m² e coberto com plástico (150 micra, tratado contra raios ultravioleta. Para caracterizar a distribuição espacial da temperatura do ar no ambiente protegido, instalaram-se termopares (cobre-constantã formando malhas, com espaçamento horizontal entre eles de 3,0 m e nas alturas de 0,5, 1,0, 2,0, 3,0 e 4,0 m em relação ao solo. Os dados foram armazenados a cada 15 min por sistemas automáticos de aquisição de dados nos ambientes protegidos. O sistema de nebulização constituiu-se de duas linhas com 70 bocais totais, instalados a uma altura de 3,0 m, utilizando-se uma pressão de trabalho de 200 kPa. A nebulização não afetou o gradiente vertical de temperatura, que manteve a tendência de aumento de temperatura com a altura, em relação ao nível do solo, enquanto o efeito na redução de temperatura pelo sistema de nebulização somente foi eficaz durante a realização da mesma. Para a representação da distribuição espacial de temperatura do ar no ambiente protegido nos diferentes níveis de altura, construiu-se superfícies isotérmicas a partir dos resultados. Verifica-se que a nebulização apresentou maior efeito na homogeneização da distribuição de temperatura no ambiente protegido no nível referente a 2,0 m de altura, em relação ao solo.This work was conducted in the experimental area of the Department of Rural Engineering of "Escola Superior de Agricultura Luiz de Queiroz", University of São Paulo, Piracicaba, São Paulo, Brazil. Two greenhouses were installed in the east-west direction, with 6.4 m of width, 17.5 m of length and 3.0 m high, with total area of 112 m²; covered by plastic of 150 micra thickness, treated against ultra violet rays. To characterize the

  16. Teor de arsênio e adsorção competitiva arsênio/fosfato e arsênio/sulfato em solos de Minas Gerais, Brasil Arsenate content, and arsenate/phosphate and arsenate/sulphate competitive adsorption in soils from Minas Gerais, Brazil

    Mari Lucia Campos

    2013-06-01

    Full Text Available A alta toxicidade de As para homens e animais gera a necessidade de estudos do comportamento químico do arsenato nos solos que possam auxiliar na mitigação de áreas contaminadas com arsênio. Este trabalho teve por objetivo avaliar o teor total e a adsorção de As na ausência e presença dos ânions fosfato e sulfato em seis diferentes classes de solos do estado de Minas Gerais, Brasil. Os solos alvo deste estudo são: o Neossolo Flúvico (RU, Gleissolo Háplico (GX, Gleissolo Melânico (GM, Latossolo Vermelho Distrófico (LVd, coletados em Lavras; Neossolo Quartzarênico (RQ, coletado em Itutinga e o Latossolo Amarelo Distrófico (LAd, coletado em Rosário, no estado de Minas Gerais. As amostras de solo foram secas, moídas e peneiradas em peneira de 2,0mm para execução do teste de adsorção e peneiradas em peneira plástica com malha de 1,5mm para determinação do teor de As, o qual foi determinado pelo método 3051A. A adsorção de As foi avaliada na dose de1500µmol L-1 de As, 1500µmol L-1 de As + 1500µmol L-1 de P e 1500µmol L-1 de As + 750µmolL-1 de S, em relação solo:solução final de 1:100, a pH 5,5 e força iônica de 15mmol L-1. Os seis solos apresentaram teor médio de As entre 0,14 e 9,3mgkg-1. A porcentagem adsorvida de arsênio na ausência dos outros ânions seguiu a sequência GM>LVd=RU=LAd=GX=RQ. A adição de fosfato e sulfato reduziu a porcentagem de arsênio adsorvido e, por consequência, houve um aumentou na concentração de arsênio disponível na solução do solo.The high toxicity of arsenic to humans and animals creates the need to study the chemical behavior of arsenate in soils that can help in the mitigation of areas contaminated with arsenic. This work aimed to evaluate the total content and adsorption in the absence and presence of phosphate and sulfate anions in six different soil classes in the state of Minas Gerais, Brazil. Soils aim of this study are: Fluvic Neosol (RU, Haplic Gleysol (GX

  17. ANÁLISE DOS PARÂMETROS DE FUNCIONAMENTO E SIMULAÇÃO COMPUTACIONAL EM UM PROTÓTIPO DE TURBINA OPERANDO A AR COMPRIMIDO

    Wesley Saldanha Nogueira Oliveira

    2016-12-01

    Full Text Available RESUMO. Este trabalho apresenta os resultados iniciais da comparação de alguns parâmetros de funcionamento do protótipo de uma turbina de ação simples, operando com ar comprimido como fluido de trabalho, realizados na unidade do SENAI de Barra do Piraí/RJ. O protótipo foi desenvolvido integralmente no Centro Universitário Geraldo Di Biase - UGB - Campus de Barra do Piraí/RJ, que inicialmente teve como o fluido de trabalho o vapor d’água, que nos testes inicias se mostrou ineficiente. A simulação computacional do sistema foi feita através do software SolidWorks na Universidade Federal Fluminense - UFF - Campus de Volta Redonda/RJ, o que permitiu determinar a faixa de trabalho que apresentou maior eficiência nos resultados experimentais do sistema por meio da relação entre pressão de operação, velocidade angular transmitida pelo fluido ao eixo da turbina e a potência da mesma. Os valores nas simulações em velocidade tangencial na região rotacional apresentaram-se convergentes aos valores experimentais medidos no protótipo.

  18. Dançar o adolescer: estudo fenomenológico com um grupo de dança de rua em uma escola

    Renata Marques Rego Miranda

    2010-12-01

    Full Text Available Esta pesquisa propôs-se a compreender os sentidos atribuídos à experiência de dançar por adolescentes praticantes da dança de rua no contexto de uma escola púbica de uma cidade do interior do Estado São Paulo. Trata-se de um estudo qualitativo de caráter exploratório e de inspiração fenomenológica. O referencial teórico norteador foi a psicologia de orientação humanista, especificamente a Abordagem Centrada na Pessoa (ACP, desenvolvida por Carl Rogers. A pesquisadora acompanhou, semanalmente, durante seis meses as aulas de dança e, posteriormente, realizou entrevistas individuais com sete alunos. Foram construídas sete narrativas focadas na experiência vivida pelos participantes da pesquisa sob o prisma da relação intersubjetiva estabelecida entre a pesquisadora e os alunos. Verificou-se que a experiência em foco proporcionou aos alunos a emergência de elementos típicos da experiência de adolescer, o que permitiu concluir que há uma aproximação com a proposta de aprendizagem significativa, desenvolvida por Rogers.

  19. Deposição e perdas da calda em feijoeiro em aplicação com assistência de ar na barra pulverizadora Spray deposition and spray loss using air-assistance boom on bean plants

    Carlos Gilberto Raetano

    2004-01-01

    Full Text Available Com o objetivo de avaliar a influência da assistência de ar na deposição da calda de pulverização, em plantas de feijoeiro (Phaseolus vulgaris aos 26 dias após a emergência (DAE, com pontas de pulverização de jato cônico vazio (JA-0,5 e JA-1 e jato plano (AXI-110015, e volumes de calda, foi realizado um experimento em delineamento inteiramente casualizado, utilizando como traçador o íon cobre. Alvos coletores (papel de filtro com 3 x 3 cm foram afixados nas superfícies adaxial e abaxial de folíolos posicionados nas partes superior e inferior das plantas. Para aplicar a solução traçadora, utilizou-se pulverizador com barras de 14 metros, com e sem assistência de ar, volumes de 60 e 100 L.ha-1, e velocidade do ar correspondente a 50% da rotação máxima do ventilador. Após a aplicação, os coletores foram lavados individualmente em solução extratora de ácido nítrico a 1,0 mol.L-1, e a quantificação dos depósitos através de espectrofotometria. A assistência de ar não influenciou na deposição da calda tanto a 60 quanto a 100 L.ha-1. O maior volume proporcionou maiores depósitos, sendo constatadas elevadas perdas para o solo (mais de 60%.Aiming to evaluate the effect of air-assistance in spray deposition on bean plants (Phaseolus vulgaris with hollow nozzles (JA-0,5 and JA-1 and flat fan nozzle type (AXI-110015, and volume rates by air-assisted and non-assisted sprayers, a completely randomized experiment was carried out using copper ion as a tracer to the evaluation of the deposits. At 26 days after emergence, artificial targets were positioned on the upper and under-side of the leaflets, on the top and bottom parts of the same plants under spray boom. For the application of tracer solution it was used a fourteen meter boom sprayer with and without air-assistance at 60 and 100 L.ha-1 of volume rates. The air flow was 50% of the maximum fan rotation. After application, targets were individually washed with an

  20. Qualidade do ar interior e sintomas respiratórios em escolas do Porto Indoor air quality and respiratory symptoms in Porto schools

    Sílvia Fraga

    2008-07-01

    Full Text Available Objectivo: Avaliar a associação entre a qualidade do ar interior em escolas da cidade do Porto e a prevalência de patologia alérgica e respiratória nos adolescentes que as frequentam. Participantes e métodos: Foi avaliada temperatura, humidade relativa, concentração de CO2 (dióxido de carbono e de COV (compostos orgânicos voláteis em nove escolas públicas da cidade do Porto. Em cada escola foram avaliados os alunos de nove turmas do 7.º, 8.º e 9.º anos, num total de 1607 adolescentes com média de idades de 14,0 (desvio-padrão=0,3 anos. A avaliação foi feita através de um questionário que compreendia questões referentes a características demográficas, sociais e comportamentais do adolescente e características da habitação de residência. Utilizou-se o questionário do International Study of Asthma and Allergies in Childhood (ISAAC para avaliar a sintomatologia respiratória. Resultados: Nos doze meses que antecederam a avaliação, referiram ter tido asma 5,8% dos adolescentes, pieira 9,2%, crises de espirros 22,0% e alterações na pele 6,6%. Após ajuste para a escolaridade dos pais, valores de CO2 > 2100 ppm associaram-se a pieira durante o exercício [OR=1,86 (IC95% 1,20 -2,89] e tosse nocturna [OR=1,40 (0,95 -2,06]. Observou-se um aumento da estimativa de risco de sintomas de pieira nos últimos 12 meses, asma alguma vez na vida e nos últimos 12 meses e tosse nocturna nas escolas com valores mais elevados de COV, embora a associação não seja estatisticamente significativa. Conclusão: Piores indicadores de qualidade do ar interior, nomeadamente concentração de CO2, associaram-se a maior sintomatologia respiratória.Aim: To evaluate the association between the indoor air quality in Porto schools and the prevalence of allergic and respiratory symptoms in adolescents. Material and methods: Temperature, relative humidity, carbon dioxide (CO2 and volatile organic compound (VOC concentrations were evaluated in nine

  1. Air-assisted boom sprayer and spray deposition on bean plants Assistência de ar em barra de pulverização e a deposição da calda em feijoeiro

    Fernando Cesar Bauer

    2003-01-01

    Full Text Available The development of safe pesticide application techniques with low volume rates, frequency and spray drift, along with the need to obtain better control level of crop pest control levels, justify the air-assistance in boom sprayers. The aim of this research was to evaluate the spray deposition on bean plants with different nozzles and volume rates by air-assisted and non-assisted sprayers. A completely randomized experiment was carried out using copper oxide as a tracer (50% metalic copper for deposit evaluation. The artificial targets were fixed on the upper and under-side of the leaflets, at the top and lower third of the same plants under the spray boom. After application, targets were washed individually with an extracting solution of nitric acid (1.0 mol L-1. The tracer deposition on the artificial targets was quantified by atomic absorption spectrofotometry. The effects of air-assisted spray were not significant in relation to spray deposition 48 days after emergence of the bean plants.A possibilidade do desenvolvimento de técnicas de aplicação de produtos fitossanitários mais seguras, com menores volumes de calda, número de aplicações e deriva, aliados à necessidade de se obter melhores níveis de controle dos agentes nocivos às plantas cultivadas, justificam o uso da assistência de ar junto à barra de pulverização. Com o objetivo de avaliar a deposição da pulverização na cultura do feijoeiro (Phaseolus vulgaris, em presença e ausência da assistência de ar junto à barra de pulverização, com diferentes pontas de pulverização e volumes de calda, foi conduzido um experimento em delineamento inteiramente casualizado, utilizando-se como traçador o óxido cuproso. Alvos artificiais (papel filtro com 3 x 3 cm foram afixados nas superfícies adaxial e abaxial de folíolos posicionados nos terços superior e inferior de plantas, selecionadas ao acaso, distribuídas perpendicularmente ao deslocamento do pulverizador. Ap

  2. Characterization of a free-air ionization chamber in direct X-ray beams as used in mammography; Caracterizacao de uma camara de ionizacao de ar-livre em feixes diretos de raios X utilizados em mamografia

    Lima, Mateus Hilario de

    2014-08-01

    At this work stability and characterization tests were undertaken on a Victoreen free-air ionization chamber, model 481. The tests were realized using direct X-ray beams as a contribution for its establishment as a primary standard system of the quantity air kerma. The characterization tests were: saturation curve, ion collection efficiency, polarity effect, response linearity with the air kerma rate and response linearity with the chamber volume variation. The ion collection efficiency allowed the determination of the ion recombination factor. Most of the test results showed agreement with the limits established by international standards. Furthermore, the air attenuation factors for the mammography beams with aluminum and molybdenum filters were obtained. The factors for photon transmission and scattering at the diaphragm edges were also determined for mammography beams with aluminum filter and for the standard beam with molybdenum filter. (author)

  3. Daños tóxicos en tejidos vegetales, producidos por aguas contaminadas con arsénico en Zimapán, Hidalgo, México Danos tóxicos em tecidos vegetais, produzidos por águas contaminadas com arsênio em Zimapán, Hidalgo, México

    Francisco Prieto García

    2006-03-01

    Full Text Available Según estudios realizados en el periodo de 1992-1998 en las aguas de los pozos, norias y manantiales, del municipio de Zimapán, Estado de Hidalgo, México, se corroboró que existía un incremento en el contenido de arsénico rebasando los límites máximos permisibles por la Norma Oficial Mexicana. La determinación de arsénico en las muestras de aguas se realizó por absorción atómica (AAS, mediante generador de hidruros (GH. En este estudio se utilizó el Vicia faba como un bioensayo para evaluar el daño genotóxico con la prueba de inducción de micronúcleos por exposición al agua de Zimapán, contaminada con As en células de raíces. Se utilizó como ensayo de control un agua de pozo de similares características del municipio de Pachuca, pero con contenidos de As por debajo de los límites de detección. Los resultados mostraron que el agua de esta región presenta altas concentraciones de arsénico y que puede provocar efectos genotóxicos que se manifiestan por la inducción de micronúcleos en las células meristemáticas de raíces de tejidos vegetales sensible.Estudos feitos no período de 1992-1998 nas águas dos poços da municipalidade de Zimapán, estado do Hidalgo, México, demostram o aumento na concentração de arsênio ultrapassando os limites máximos permissíveis pela norma oficial mexicana. A determinação de arsênio nas amostras de água foi feita por absorção atômica (AA, por meio do gerador de hidruros (GH. Neste estudo, o Vicia faba foi usado como bioensaio para avaliar os danos genotóxicos com o teste da indução dos micronúcleos pela exposição à água de Zimapán, contaminada com arsênio em células de raízes. Como controle, foi usada uma água com similares características, do município de Pachuca, mas com índices abaixo dos limites de detecção. Os resultados mostraram que a água desta região apresenta altas concentrações de arsênico e que os efeitos genotóxicos manifestam-se pela

  4. Origem e distribuição do nervo isquiático em fetos de suínos (Sus scrofa domesticus – Linnaeus, 1758 da linhagem Pen Ar Lan

    Lázaro Antônio Santos

    2012-10-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2013v26n1p147 Estudou-se a origem e distribuição do nervo isquiático em 31 fetos de suínos da linhagem Pen Ar Lan, sendo 22 machos e nove fêmeas, após ser fixados em solução aquosa de formaldeído a 10%. Nesses, animais, as vértebras lombares variaram de cinco a sete, com predominância de seis, o que contribuiu para variações na origem do referido nervo. O nervo isquiático originou-se em 80,64% dos antímeros, do ramo ventral do quinto nervo espinhal lombar (L5; em 96,77% de L6; em 6,45% de L7; em 100% de S1; e em 64,51% de S2. A composição do referido nervo ocorreu em 45,16% dos animais pela união de L5, L6, S1 e S2; em 32,25% de L5, L6 e S1; em 12,90% de L6, S1 e S2; em 6,45% de L6, L7 e S1; e em 3,22% de L5, S1 e S2. Houve simetria na origem do nervo isquiático em todos os espécimes estudados. Esse nervo emitiu ramos para os músculos glúteo superficial, semitendinoso, semimembranoso e bíceps femoral em todos os espécimes, e em menor frequência, para os músculos gêmeos, quadrado femoral, adutores, e glúteos médio, acessório e profundo. Em 74,19% da amostra, foi observado um ramo comunicante com nervo pudendo.

  5. Ars Electronica

    Kristensen, Thomas Bjørnsten

    2009-01-01

    Anmeldelse af Ars Electronica festivalen 3. - 8. september, 2009 i Linz, Østrig, der fejrede 30 års jubilæum under temaet "Human Nature". Festivalen fokuserer på interaktion mellem menneske, teknologi, kunst og samfund med særlig vægt på udviklingen af computeren og det digitale. Udgivelsesdato: 15.12...

  6. Origem e distribuição do nervo isquiático em fetos de suínos (Sus scrofa domesticus – Linnaeus, 1758) da linhagem Pen Ar Lan

    Santos, Lázaro Antônio; Silva, Frederico Ozanam Carneiro; Rosa, Luciana Aparecida; Menezes, Lorena Tannús; Canabrava, Álvaro Carneiro Matoso Nunes; Lizardo, Frederico Balbino; Silva, Daniela Cristina Oliveira; Sousa, Gilmar Cunha

    2012-01-01

    http://dx.doi.org/10.5007/2175-7925.2013v26n1p147 Estudou-se a origem e distribuição do nervo isquiático em 31 fetos de suínos da linhagem Pen Ar Lan, sendo 22 machos e nove fêmeas, após ser fixados em solução aquosa de formaldeído a 10%. Nesses, animais, as vértebras lombares variaram de cinco a sete, com predominância de seis, o que contribuiu para variações na origem do referido nervo. O nervo isquiático originou-se em 80,64% dos antímeros, do ramo ventral do quinto nervo espinhal lomb...

  7. Evaluation of entrance surface air kerma in pediatric chest radiography

    Porto, L.; Lunelli, N.; Paschuk, S.; Oliveira, A.; Ferreira, J.L.; Schelin, H.; Miguel, C.; Denyak, V.; Kmiecik, C.; Tilly, J.; Khoury, H.

    2014-01-01

    The objective of this study was to evaluate the entrance surface air kerma in pediatric chest radiography. An evaluation of 301 radiographical examinations in anterior–posterior (AP) and posterior–anterior (PA) (166 examinations) and lateral (LAT) (135 examinations) projections was performed. The analyses were performed on patients grouped by age; the groups included ages 0–1 y, 1–5 y, 5–10 y, and 10–15 y. The entrance surface air kerma was determined with DoseCal software (Radiological Protection Center of Saint George's Hospital, London) and thermoluminescent dosimeters. Two different exposure techniques were compared. The doses received by patients who had undergone LAT examinations were 40% higher, on average, those in AP/PA examinations because of the difference in tube voltage. A large high-dose “tail” was observed for children up to 5 y old. An increase in tube potential and corresponding decrease in current lead to a significant dose reduction. The difference between the average dose values for different age ranges was not practically observed, implying that the exposure techniques are still not optimal. Exposure doses received using the higher tube voltage and lower current-time product correspond to the international diagnostic reference levels. - Highlights: • The entrance surface air kerma of chest X-ray examinations in pediatric patients was estimated. • The data were analyzed for patients aged up to 15 y, stratified by age. • The doses of LAT examinations were 40% higher than of AP/PA because of kV used. • An increase in kV with a decrease in mAs leads to significant dose reduction

  8. Condicionamento de ar em salas de operação e controle de infecção - uma revisão

    May Socorro Martinez Afonso

    2006-04-01

    Full Text Available Revisão bibliográfica, realizada junto aos bancos de dados MED LINE, LILACS, SCIELO, Ministério da Saúde e outros buscadores, com o objetivo de identificar os fatores que torna o ar condicionado fonte de contaminação ambiental. O ar é contaminado por partículas que transportam microrganismos. As fontes de partículas incluem pacientes e equipe cirúrgica. O controle da temperatura, umidade relativa, pressão, número de trocas de ar realizadas por hora, paramentação, tráfego, número de pessoas nas salas e manutenção e limpeza do sistema de ar condicionado dos centros cirúrgicos, são fatores importantes na redução do número de microrganismos no ambiente de sala de operação.

  9. Radioproteção, dose e risco em exames radiográficos nos seios da face de crianças, em hospitais de Belo Horizonte, MG Radioprotection, doses and risks in the radiological assessment of paranasal sinuses in children, in hospitals of Belo Horizonte, MG

    Marco Aurélio de Sousa Lacerda

    2007-12-01

    Full Text Available OBJETIVO: Avaliar a freqüência das incidências radiográficas realizadas nos seios da face de pacientes pediátricos em hospitais de Belo Horizonte, MG, as condições de radioproteção, as técnicas radiográficas empregadas, o kerma no ar de entrada e as doses nos órgãos mais expostos. MATERIAIS E MÉTODOS: Foram coletados os dados dos pacientes e parâmetros de técnica radiográfica empregados em exames de crianças de 1 a 16 anos de idade, em cinco salas de quatro hospitais da cidade, observando, também, aspectos de proteção radiológica. O kerma no ar de entrada foi estimado a partir dos rendimentos dos tubos de raios-x e as doses nos órgãos utilizando o software PCXMC. RESULTADOS: Os valores médios do kerma no ar de entrada para as cinco salas foram, respectivamente, 1.398 µGy, 829 µGy, 877 µGy, 1.168 µGy e 3.886 µGy para pacientes entre 1 e 5 anos de idade. CONCLUSÃO: Foi constatado que as incidências mento-naso e fronto-naso são comumente solicitadas em conjunto, na maioria dos hospitais, o que confere dose significativa para os pacientes. Os riscos para os pacientes podem ser diminuídos mediante a utilização de cilindros de colimação, a não-utilização de grades antiespalhamento, o emprego de altos valores de tensão e baixos valores de tempo.OBJECTIVE: The present study was aimed at evaluating the frequency of radiographic assessment of paranasal sinuses in pediatric patients in hospitals of Belo Horizonte, MG, Brazil. Additionally, aspects regarding radiation protection conditions and radiographic parameters were evaluated, and entrance air kerma and organ doses were estimated. MATERIALS AND METHODS: Patients' data and parameters of radiographic technique employed in the assessment of children in the age range between 1 and 16 years were collected in five examination rooms of four hospitals in Belo Horizonte, also taking into consideration the radiation protection aspects. Entrance air kerma calculation was

  10. Evaluation of entrance surface air kerma in pediatric chest radiography

    Porto, L.; Lunelli, N.; Paschuk, S.; Oliveira, A.; Ferreira, J. L.; Schelin, H.; Miguel, C.; Denyak, V.; Kmiecik, C.; Tilly, J.; Khoury, H.

    2014-11-01

    The objective of this study was to evaluate the entrance surface air kerma in pediatric chest radiography. An evaluation of 301 radiographical examinations in anterior-posterior (AP) and posterior-anterior (PA) (166 examinations) and lateral (LAT) (135 examinations) projections was performed. The analyses were performed on patients grouped by age; the groups included ages 0-1 y, 1-5 y, 5-10 y, and 10-15 y. The entrance surface air kerma was determined with DoseCal software (Radiological Protection Center of Saint George's Hospital, London) and thermoluminescent dosimeters. Two different exposure techniques were compared. The doses received by patients who had undergone LAT examinations were 40% higher, on average, those in AP/PA examinations because of the difference in tube voltage. A large high-dose “tail” was observed for children up to 5 y old. An increase in tube potential and corresponding decrease in current lead to a significant dose reduction. The difference between the average dose values for different age ranges was not practically observed, implying that the exposure techniques are still not optimal. Exposure doses received using the higher tube voltage and lower current-time product correspond to the international diagnostic reference levels.

  11. Status of air kerma and absorbed dose standards in India

    Vijayam, M.; Ramanathan, G.; Patki, V.S.; Soman, A.T.; Shigwan, J.B.; Vinatha, S.P.; Jadhavgaonkar, P.S.; Kadam, V.D.; Shaha, V.V.; Abani, M.C.

    2002-01-01

    Full text: The Radiation Safety Systems Division of Bhabha Atomic Research Centre, India maintains Primary and Secondary Standards of various parameters of radiation measurements and provides calibration services to various users of radiation in the country. This is an apex laboratory in India and plays a pivotal role in ensuring accurate radiological measurements. The laboratory coordinates national intercomparisons of radiation measurements to maintain their uniformity and traceability and is linked through various programmes with the other International organizations such as Bureau Internationale des Poids et Mesures (BIPM) Paris, International Atomic Energy Agency (IAEA) Vienna, Asia Pacific Metrology Programme (APMP) Taiwan. It is the recognized Regional Secondary Standards Dosimetry Laboratory (SSDL) of IAEA/WHO (World Health Organisation). This paper brings out the status of various primary and secondary standards for radiological measurements maintained at BARC. 1. Primary Exposure/Air-kerma standard at Co-60 energy (therapy level): The primary standard for exposure/ air-kerma measurements maintained at BARC is a graphite cavity chamber of volume 4.362 cc with an internal diameter of 1.8 cm, internal height of 1.78 cm and wall thickness of 704.3mg/cm 2 . Correction factors for the difference between electron stopping powers, photon mass energy absorption coefficients of air and graphite wall, correction for recombination, radiation field non-uniformity, stem scatter and polarity effect are applied and the maximum overall uncertainty in the realisation of exposure/air-kerma is around ±1%. This standard has been intercompared with IAEA and BIPM through transfer standard and the agreement in the results are better than ±1%. An intercomparison under the APMP programme is to be held during May, 2002. 2. Primary Exposure/Air-kerma standard at protection and brachytherapy level: A set of three spherical graphite-walled cavity chambers of different air

  12. Portable radiation meters evaluation in high rates of air kerma

    Damatto, Willian B.; Potiens, Maria da Penha A.; Vivolo, Vitor

    2015-01-01

    A set of portable meters of ionizing radiation high rates of air kerma (teletectors) commonly used in emergencies in Brazil and sent to the Calibration Laboratory of IPEN were under several tests and analyst is parameters for the detectors behavior were established, specifying their sensitivities and operating characteristics. Applied tests were: reading equipment variation with battery voltage, geotropism effect, energy dependence, the angular dependence and overload. Thus it was possible to determine the most common characteristic found in these equipment (quality control programs). The behavior of 17 portable meters was analyzed and in this study, 10 of them have been tested. It was performed to characterize the gamma irradiating system (radiation dosimetry field) that possesses higher activity in teletectors for testing of larger measuring range. New calibration criteria were established following international recommendations. Therefore, it was made the improvement of the quality control programme of portable meters of ionizing radiation high rates of air kerma calibration laboratory, benefiting the users of such equipment with better consistent calibration measurements. (author)

  13. Air Kerma above environmental radiometric calibration facility for field equipment

    Conti, C.C.; Sachett, I.A.; Bertelli, L.; Lopes, R.T.

    2000-01-01

    The use of gamma ray spectrometers broadened the aims of gamma ray surveys, stead of measuring only the gross radiation, as was done with the GM tubes, it is now possible to be used for uranium exploration, geological mapping as an aid to the exploration of non radioactive ores like gold and tin, radiation background measurements to identify hot spots for radiation hazard evaluation and environmental monitoring of fallout from radiological and nuclear accidents. It became necessary to carefully and precisely calibrate the field equipment to be used to get all the information from such uses. There is an environmental radiometric calibration facility for field equipment, consisting of eight radioactive concrete sources, at the Institute of Radioprotection and Dosimetry - IRD (CNEN/Brazil). These sources are cylindrical with 3 m diameter, 0.5 m thick and weigh about 7.5 tons each. The amount and type of the radioactive material, 238 U and 232 Th and 40 K ores in secular radioactive equilibrium, added to the concrete to simulate rock outcrops, varies in order to obtain different gamma fields, varying in both energy and intensity. These different radiation fields were measured with a HPGe portable detector, specifically calibrated for spectrum stripping, and the air kerma energy distribution was determined for each concrete source and compared with the total air kerma calculated from the nuclide concentration and by others radiometric methods. (author)

  14. Infecções ortopédicas em pacientes submetidos a artroplastias total de quadril e joelho, hemiartroplastias e osteossínteses: incidência, fatores de risco e influência do ar do Centro Cirúrgico em um Hospital Universitário Brasileiro

    Dolinger, Elias José Oliveira Von

    2008-01-01

    Os objetivos foram avaliar o nível da contaminação do ar durante artroplastias total de quadril e joelho, hemiartroplastias e osteossínteses, incidência de infecção e fatores de risco associados a infecções ortopédicas em cirurgias primárias. As avaliações microbiológicas do ar foram em: sete artroplastias total de quadril e joelho, três de hemiartroplastias e sete de osteossínteses, com a exposição de placas de petri, por uma hora, no início e final da cirurgia. O número de pe...

  15. Influence of atmospheric rainfall to γ radiation Kerma rate in surface air

    Xu Zhe; Wan Jun; Yu Rongsheng

    2009-01-01

    Objective: To investigate the influence rule of the atmospheric Rainfall to the γ radiation Kerma rate in surface air in order to revise the result of its measurement during rainfall. Methods: The influence factors of rainfall to the measurement of the γ radiation Kerma rate in air were analyzed and then the differential equation of the correlation factors was established theoretically, and by resolving the equation, the mathematical model Was obtained. The model was discussed through several practical examples. Results: The mathematical model was coincided with the tendency of curve about the measured data on the influence rule of rainfall to the γ radiation Kerma rate in surface air. Conclusion: By using the theoretical formula in this article which is established to explain the relationship between the rainfall and the γ radiation Kerma rate in surface air, the influence of rainfall to the γ radiation Kerma rate in surface air could be correctly revised. (authors)

  16. Reference air kerma and kerma-area product as estimators of peak skin dose for fluoroscopically guided interventions

    Kwon, Deukwoo; Little, Mark P.; Miller, Donald L.

    2011-01-01

    Purpose: To determine more accurate regression formulas for estimating peak skin dose (PSD) from reference air kerma (RAK) or kerma-area product (KAP). Methods: After grouping of the data from 21 procedures into 13 clinically similar groups, assessments were made of optimal clustering using the Bayesian information criterion to obtain the optimal linear regressions of (log-transformed) PSD vs RAK, PSD vs KAP, and PSD vs RAK and KAP. Results: Three clusters of clinical groups were optimal in regression of PSD vs RAK, seven clusters of clinical groups were optimal in regression of PSD vs KAP, and six clusters of clinical groups were optimal in regression of PSD vs RAK and KAP. Prediction of PSD using both RAK and KAP is significantly better than prediction of PSD with either RAK or KAP alone. The regression of PSD vs RAK provided better predictions of PSD than the regression of PSD vs KAP. The partial-pooling (clustered) method yields smaller mean squared errors compared with the complete-pooling method.Conclusion: PSD distributions for interventional radiology procedures are log-normal. Estimates of PSD derived from RAK and KAP jointly are most accurate, followed closely by estimates derived from RAK alone. Estimates of PSD derived from KAP alone are the least accurate. Using a stochastic search approach, it is possible to cluster together certain dissimilar types of procedures to minimize the total error sum of squares.

  17. Viscosidade cinemática de pastas cimentícias com incorporadores de ar avaliadas em diferentes temperaturas Kinematic viscosity of cement pastes with air-entrained admixtures evaluated in different temperatures

    R. C. O. Romano

    2012-03-01

    Full Text Available A presença de aditivos incorporadores de ar (AIA em suspensões cimentícias torna esses materiais sensíveis às etapas de processamento e às condições ambientais de preparo das composições. Diversos estudos têm sido reportados em literatura avaliando o efeito de incorporadores de ar nas propriedades de materiais cimentícios, sobretudo no estado endurecido. Porém o efeito da temperatura na incorporação de ar e nas propriedades reológicas dessas composições tem sido menos investigado, sendo este o objetivo do presente trabalho. Para tanto, foram avaliadas as características de pastas cimentícias, compostas por cimentos CPIIF ou CPIIE e dois tipos de AIA, em função da variação da temperatura. O conceito de viscosidade cinemática foi adotado na análise dos resultados para compensar diferenças de inércia das pastas com densidades distintas. Os resultados mostraram que o tipo de cimento, a presença do aditivo e a temperatura influenciaram significativamente na incorporação de ar e nas propriedades reológicas.Air-entrained admixtures (AEA makes the cementitious pastes very sensitive to the mix process, environmental conditions and, consequently modifies the final properties. Many studies have been found in literature evaluating the AEA effect on the material properties, mainly in the hardened state. However, the temperature effect in the air incorporation and rheological properties have been less investigated, and this has been the objective of our work. The properties of cementitious pastes formulated with CPIIE or CPIIF and different air-entrained admixtures were evaluated in distinct temperatures. Furthermore, the concept of kinematic viscosity was used in the analysis of the results to compensate the differences in the inertia of cement pastes with different densities. The results shown that the cement type, the additive presence and the temperature significantly affects the air incorporation and the rheological

  18. Avaliação de Coberturas de Cabanas de Maternidade em Sistema Intensivo de Suínos Criados ao Ar Livre (Siscal, no Verão Maternity Hut Covering Evaluation in Outdoor Pig Production System, Summer Data

    Paulo Giovanni de Abreu

    2001-12-01

    Full Text Available O objetivo deste trabalho foi estudar as condições térmicas ambientais de diferentes materiais de cobertura de cabana de maternidade, no verão, utilizando os seguintes tratamentos: 1 cabana de maternidade coberta com fécula de isopor 2 cabana de maternidade coberta com isolamento de alumínio 3 cabana de maternidade coberta com tela e capim na cobertura 4 cabana de maternidade coberta com lona e capim na cobertura 5 ambiente ao ar livre e 6 à sombra da árvore. O delineamento experimental usado foi em blocos casualizados, em esquema de parcelas subdivididas, com 6 tratamentos nas parcelas, 5 horas nas subparcelas e 3 repetições. A categoria animal utilizada foi porcas lactantes, Landrace x Large White, distribuídas aleatoriamente por ordem de parto. Foi determinada a Umidade Relativa do Ar (UR, a Velocidade do Ar, a Temperatura Ambiente (Ta e foram calculados o Índice de Temperatura de Globo e Umidade (ITGU e a Carga Térmica Radiante (CTR. Apesar de os materiais utilizados como cobertura de maternidade terem melhorado o conforto térmico das porcas em relação as condições ambientais, ainda, não foram suficientes em atender as condições ideais de conforto térmico.The objective of this study was to evaluate the environmental thermal conditions of different maternity hut covering materials, in the summer period through the following treatments: 1 maternity hut with polystyrene fecula covering 2 maternity hut with isolation of aluminum covering 3 maternity hut with screen and grass covering 4 maternity hut with canvas and grass covering 5 outdoor environment 6 under shade a tree. The six treatments were arranged in a randomized split-plot design where the six treatments were in the plot with five schedules hours in the subplots and three replicates. Sow lactantes Landrace x Large White were alloted at random considering farrowing order. Relative Humidity Air (RH, Air Speed, and Environmental Temperature (Te data were determined

  19. arXiv ARS Leptogenesis

    Drewes, M.; Hernandez, P.; Kekic, M.; Lopez-Pavon, J.; Racker, J.; Rius, N.; Salvado, J.; Teresi, D.

    2018-02-28

    We review the current status of the leptogenesis scenario originally proposed by Akhmedov, Rubakov and Smirnov (ARS). It takes place in the parametric regime where the right-handed neutrinos are at the electroweak scale or below and the CP-violating effects are induced by the coherent superposition of different right-handed mass eigenstates. Two main theoretical approaches to derive quantum kinetic equations, the Hamiltonian time evolution as well as the Closed-Time-Path technique are presented, and we discuss their relations. For scenarios with two right-handed neutrinos, we chart the viable parameter space. Both, a Bayesian analysis, that determines the most likely configurations for viable leptogenesis given different variants of flat priors, and a determination of the maximally allowed mixing between the light, mostly left-handed, and heavy, mostly right-handed, neutrino states are discussed. Rephasing invariants are shown to be a useful tool to classify and to understand various distinct contributions to...

  20. Secondary bremsstrahlung and the energy-conservation aspects of kerma in photon-irradiated media.

    Kumar, Sudhir; Nahum, Alan E

    2016-02-07

    Kerma, collision kerma and absorbed dose in media irradiated by megavoltage photons are analysed with respect to energy conservation. The user-code DOSRZnrc was employed to compute absorbed dose D, kerma K and a special form of kerma, K ncpt, obtained by setting the charged-particle transport energy cut-off very high, thereby preventing the generation of 'secondary bremsstrahlung' along the charged-particle paths. The user-code FLURZnrc was employed to compute photon fluence, differential in energy, from which collision kerma, K col and K were derived. The ratios K/D, K ncpt/D and K col/D have thereby been determined over a very large volumes of water, aluminium and copper irradiated by broad, parallel beams of 0.1 to 25 MeV monoenergetic photons, and 6, 10 and 15 MV 'clinical' radiotherapy qualities. Concerning depth-dependence, the 'area under the kerma, K, curve' exceeded that under the dose curve, demonstrating that kerma does not conserve energy when computed over a large volume. This is due to the 'double counting' of the energy of the secondary bremsstrahlung photons, this energy being (implicitly) included in the kerma 'liberated' in the irradiated medium, at the same time as this secondary bremsstrahlung is included in the photon fluence which gives rise to kerma elsewhere in the medium. For 25 MeV photons this 'violation' amounts to 8.6%, 14.2% and 25.5% in large volumes of water, aluminium and copper respectively but only 0.6% for a 'clinical' 6 MV beam in water. By contrast, K col/D and K ncpt/D, also computed over very large phantoms of the same three media, for the same beam qualities, are equal to unity within (very low) statistical uncertainties, demonstrating that collision kerma and the special type of kerma, K ncpt, do conserve energy over a large volume. A comparison of photon fluence spectra for the 25 MeV beam at a depth of  ≈51 g cm−2 for both very high and very low charged-particle transport cut-offs reveals the considerable

  1. Poluição do ar e doenças respiratórias e cardiovasculares: estudo de séries temporais em Cubatão, São Paulo, Brasil

    Adelaide Cassia Nardocci

    2013-09-01

    Full Text Available Foi avaliado o impacto da poluição do ar nas internações por doenças respiratórias e cardiovasculares em residentes do Município de Cuba-tão, São Paulo, Brasil. Utilizaram-se modelos de séries temporais, com modelos aditivos generalizados, em regressão de Poisson, testando como variáveis independentes as concentrações diárias de material particulado (PM10; dióxido de enxofre (SO2 e o ozônio (O3. Como variáveis de controle a temperatura, umidade, dias da semana e feriados. Para cada incremento de 10µg/m³ de PM10, encontrou-se um excesso de internações de 4,25% (IC95%: 2,82; 5,71; 5,74% (IC95%: 3,80; 7,71 e 2,29% (IC95%: 0,86; 3,73 para doenças respiratórias totais, doenças respiratórias em menores de 5 anos e doenças cardiovasculares em maiores de 39 anos, respectivamente. O SO2 apresentou relação com as doenças cardiovasculares em maiores de 39 anos de 3,51% (IC95%: 1,24; 5,83 e o O3 com as doenças cardiovasculares em maiores de 39 anos: 2,85% (IC95%: 0,77; 4,98 e doenças respiratórias em menores de 5 anos: 3,91% (IC95%: 1,37; 6,51. Os efeitos da poluição atmosférica na saúde em Cubatão são pronunciados, indicando a necessidade de melhoria das políticas de controle.

  2. Small angle Ar2+ + Ar collisions

    Stevens, J.J.

    1983-01-01

    Electron capture in Ar 2+ + Ar is studied at low keV energies. Using Ar 2+ + He collisions as a calibration, it is shown that the dominant single electron capture process is endothermic and of the type Ar 2+ ( 3 P) + ArAr + ( 2 P) + Ar + (3s 2 3p 4 nI), with nI primarily being 3d and 4p. Weaker exothermic processes are also found and are due mainly to the existence of long-lived highly-excited states in the incident Ar 2+ beam. The direct scattering and double electron capture processes are also studied. Direct scattering occurs with no target excitation. Differential cross sections are presented for the collision processes. The single electron capture results are interpreted using a simple model in which a strongly attractive intermediate state couples with incident and outgoing channels

  3. SECAGEM DE SEMENTES DE SOJA EM SILO COM DISTRIBUIÇÃO RADIAL DO FLUXO DE AR: I. MONITORAMENTO FÍSICO DRYING OF SOYBEAN SEEDS IN A RADIAL AIR FLOW DRYER: I. PHYSICAL MONITORING

    LUIZ CARLOS MIRANDA

    1999-11-01

    Full Text Available O trabalho foi desenvolvido com o objetivo de avaliar a evolução física do processo de remoção de água das sementes em secador estacionário, com cilindro central perfurado e distribuição radical de ar. A pesquisa foi conduzida com sementes de soja, variando o fluxo (26,9, 28,4 e 33,2 m³/minuto/t e a temperatura do ar insuflado (42, 46 e 50ºC, considerando a posição das sementes (17, 34 e 51 cm em relação ao cilindro de insuflação e o tempo de secagem (zero a doze horas, com intervalos de duas horas. Foram caracterizados o ar ambiente, o ar insuflado, as temperaturas e os teores de água da massa, as velocidades e curvas de secagem. As avaliações realizadas destacaram vantagens físicas operacionais da combinação de 28,4 m³/minuto/t com 46ºC e o contrário, com a combinação de 26,9 m³/minuto/t com 42ºC.The purpose of this research was to study several physical parameters of soybean seed drying submitted to stationary process with radial air distribution by combining different air flows (26.9, 28.4 and 33.2 m³/minute/ton and temperatures (42, 46 and 50ºC, considering seed positions in the seed mass (17, 34 and 51 cm in relation to the insuflation cylinder and drying periods (zero to twelve hours with two-hour intervals. Environmental air, insuflation air, seed temperatures, moisture content of seeds, drying speed and drying curves were characterized. Considering the evaluated parameters during the drying process, the physical advantages of the combination of 28.4 m³/minute/ton with 46ºC, and the desadvantage of the combination of 26.9 m³/minute/ton with 42ºC were observed.

  4. X-rays spectrum and air Kerma during a mammography study; Espectro de los rayos X y Kerma en aire durante un estudio mamografico

    Ramirez G, J. [Instituto Nacional de Estadistica Geografia e Informatica, Av. Heroes de Nacozari Sur 2301, Fracc. Jardines del Parque, 20276 Aguascalientes (Mexico); Hernandez V, R.; Hernandez D, V. M.; Vega C, H. R. [Unidad Academica de Estudios Nucleares, Universidad Autonoma de Zacatecas, Cipres 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)], e-mail: fermineutron@yahoo.com

    2009-10-15

    In this calculation series was modeled the source of electrons, the target and the filter. Using thermoluminescent dosemeters of ZrO{sub 2}+PTFE the air Kerma was measured in five points located on a phantom made with acrylic and water when it was exposed to a X-rays beam produced by electrons of 24 KeV and 10 m A of current that produces a mammography. The air Kerma values at the entrance surface of the phantom were compared with values calculated by Monte Carlo methods. The air Kerma values measured indicate that approximately the five points receive the same air Kerma, what means that the beam is homogeneous, of the Monte Carlo calculations we find that the center receives a greater dose what implies that the beam is not uniform, the explanation of this fact is attributed to was used a simple model in the calculations, nevertheless, the air Kerma average measured at the entrance surface of the phantom was of 0.96 +{sub -} 0.03 m G, while the other obtained by the calculations was of 0.96 +{sub -} 0.06 mGy, to compare both do not exist significant differences. (author)

  5. Microbiological air quality of processing areas in a dairy plant as evaluated by the sedimentation technique and a one-stage air sampler Qualidade microbiológica do ar de ambientes de processamento em indústria de laticínios avaliada por amostrador de ar de um estágio e pela técnica da sedimentação

    Valéria Costa Salustiano

    2003-07-01

    Full Text Available The microbiological air quality at processing areas in a dairy plant was evaluated by using a one-stage air sampler, based on Andersen principles (impaction technique and by culture settling plate technique, also known as sedimentation technique. Among these areas, milk reception, packaging, and pasteurization rooms were included. Rooms where cheese, yogurt, butter and "doce de leite"(Latin American typical treat made of concentrated milk and sugar are made were also evaluated. For all processing areas, the numbers of mesophilic aerobic bacteria and yeast and molds recovered by air sampler were higher than 90 CFU·m-3 - the maximum value recommended by American Public Health Association (APHA. In four of the six processing areas, the microbial numbers were higher than APHA's standard (30 CFU.cm-2.week-1 according to culture settling plate technique. The results showed a difference (pFoi avaliada a microbiota do ar dos ambientes de recepção, embalagem e pasteurização de leite, produção de queijos, de iogurte e de doce de leite e manteiga em uma indústria de laticínios pelas técnicas de sedimentação e de impressão em ágar utilizando um amostrador de ar de um estágio baseado no princípio de Andersen. As contagens de microrganismos mesófilos aeróbios e de fungos filamentosos e leveduras pela técnica impressão em ágar ultrapassaram 90UFC·m-3 de ar, valor máximo recomendado pela APHA. Pela técnica de sedimentação, as contagens microbianas do ar de quatro ambientes também ultrapassaram 30UFC·cm-2·semana-1, conforme recomendação da APHA. Os ambientes diferiram (p<0,05 apenas para os números de Staphylococcus aureus. (<1,0 a 4,3 UFC.m-3. As contagens microbianas por impressão em ágar foram de 2 a 10 vezes maiores que as obtidas por sedimentação, evidenciando a maior capacidade da impressão em ágar em determinar microrganismos do ar, inclusive patógenos. Quanto à distribuição da microbiota do ar, houve a predomin

  6. Ar-Ar_Redux: rigorous error propagation of 40Ar/39Ar data, including covariances

    Vermeesch, P.

    2015-12-01

    Rigorous data reduction and error propagation algorithms are needed to realise Earthtime's objective to improve the interlaboratory accuracy of 40Ar/39Ar dating to better than 1% and thereby facilitate the comparison and combination of the K-Ar and U-Pb chronometers. Ar-Ar_Redux is a new data reduction protocol and software program for 40Ar/39Ar geochronology which takes into account two previously underappreciated aspects of the method: 1. 40Ar/39Ar measurements are compositional dataIn its simplest form, the 40Ar/39Ar age equation can be written as: t = log(1+J [40Ar/39Ar-298.5636Ar/39Ar])/λ = log(1 + JR)/λ Where λ is the 40K decay constant and J is the irradiation parameter. The age t does not depend on the absolute abundances of the three argon isotopes but only on their relative ratios. Thus, the 36Ar, 39Ar and 40Ar abundances can be normalised to unity and plotted on a ternary diagram or 'simplex'. Argon isotopic data are therefore subject to the peculiar mathematics of 'compositional data', sensu Aitchison (1986, The Statistical Analysis of Compositional Data, Chapman & Hall). 2. Correlated errors are pervasive throughout the 40Ar/39Ar methodCurrent data reduction protocols for 40Ar/39Ar geochronology propagate the age uncertainty as follows: σ2(t) = [J2 σ2(R) + R2 σ2(J)] / [λ2 (1 + R J)], which implies zero covariance between R and J. In reality, however, significant error correlations are found in every step of the 40Ar/39Ar data acquisition and processing, in both single and multi collector instruments, during blank, interference and decay corrections, age calculation etc. Ar-Ar_Redux revisits every aspect of the 40Ar/39Ar method by casting the raw mass spectrometer data into a contingency table of logratios, which automatically keeps track of all covariances in a compositional context. Application of the method to real data reveals strong correlations (r2 of up to 0.9) between age measurements within a single irradiation batch. Propertly taking

  7. Efeito da velocidade do ar em barra de pulverização na deposição de produtos fitossanitários em feijoeiro Efect of the air speed in air-assisted sprayer on bean crop pesticide spray deposition

    Carlos Gilberto Raetano

    2003-01-01

    Full Text Available Com o objetivo de avaliar o efeito da variação da velocidade do ar em barra de pulverização na deposição da calda na cultura do feijoeiro (Phaseolus vulgaris, realizou-se o experimento em 9 e 10 de outubro de 2000, no Centro de Pesquisas Agronômicas - Cyanamid, em Iracemápolis (SP, em delineamento inteiramente casualizado, aos 48 dias após a emergência (DAE. Para isso, convencionou-se que a rotação máxima do ventilador, medida com o auxílio de fototacômetro, possibilitou a obtenção da velocidade máxima do ar na barra de pulverização e, a partir daí, níveis de 50% e 75% da velocidade máxima do ar. Alvos artificiais foram fixados na superfície adaxial e na abaxial de folíolos posicionados, nos terços superior e inferior das plantas selecionadas, ao acaso, e distribuídas perpendicularmente ao deslocamento do pulverizador. O óxido cuproso (50% de cobre metálico foi o traçador utilizado em pulverização e a determinação quantitativa dos depósitos feita com o uso da espectrofotometria de absorção atômica. Os resultados sugerem que a variação da velocidade do ar na barra pulverizadora não influenciou sobre os níveis de depósitos no feijoeiro, aos 48 DAE, nas condições do presente trabalho.The aim of this research was to evaluate the effects of air speed in air-assisted sprayer on bean crop (Phaseolus vulgaris spray deposition. The experiment was carried out at 48 days after crop emergence and the experimental design was randomized. The maximum air speed in spray boom was obtained with the maximum of the fan rotation by a phototachometer. The middle and third air speed were obtained with lower fan rotation. The tracer used in the spray solution was copper oxid (50% of the metalic copper. It was measured by atomic spectrophotometry absorption equipment. The targets were fixed on the under and upper-side of the leaves, in the top and lower third of the same plant under the spray boom. The effects of variation

  8. Resfriamento de carcaças de frango por imersão em água e ar forçado

    Rodrigues, Luiz Gustavo Gonçalves

    2013-01-01

    Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia de Alimentos, Florianópolis, 2013. O Brasil e principalmente o estado de Santa Catarina ocupam uma posição de destaque no mercado internacional com respeito à produção e a exportação de carne de frango. Em uma linha de processamento industrial, a etapa de resfriamento de carcaças de frango até a temperatura central do músculo peitoral atingir 4 °C, é de suma importância pa...

  9. CONSIDERAÇÕES SOBRE A POLUIÇÃO DO AR EM CURITIBA-PR FACE A SEUS ASPECTOS DE URBANIZAÇÃO

    Inês Moresco Danni-Oliveira

    2000-12-01

    Full Text Available O presente texto aborda as feições morfo-estruturais assumidas por Curitiba diante de seu crescimento urbano e dos Planos Diretores a ela aplicados neste século, na perspectiva de suas interações com as questões de qualidade do ar da cidade. Considerations about air pollution in Curitiba-PR in vew of its urbanization Abstract This paper is concerning about the morpho-estructural characters given to Curitiba by its urban growing and its urban planning in this century, under the perspective of their interaction with the city air quality problems.

  10. Correlation and uncertainties evaluation in backscattering of entrance surface air kerma measurements

    Teixeira, G.J.; Sousa, C.H.S.; Peixoto, J.G.P., E-mail: gt@ird.gov.br [Instituto de Radioproteção e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2017-07-01

    The air kerma measurement is important to verify the applied doses in radiodiagnostic. The literature determines some methods to measure the entrance surface air kerma or entrance surface dose but some of this methods may increase the measurement with the backscattering. Were done setups of measurements to do correlations between them. The expanded uncertainty exceeded 5% for measurements with backscattering, reaching 8.36%, while in situations where the backscattering was avoided, the uncertainty was 3.43%. (author)

  11. Uso de água residual do ar condicionado e de agua pluvial como gestão da oferta em uma edificação comercial: estudo de caso

    Celso Silva Bastos

    2013-12-01

    Full Text Available O conceito do uso racional para a conservação de água consiste na gestão da demanda e da oferta de água, com ações voltadas para o fornecimento de fontes alternativas visando suprir o uso em áreas menos nobres por águas de qualidade inferior. Este trabalho tem por objetivo mostrar a aplicação de um sistema que aproveita a água drenada dos evaporadores de ar-condicionado e das águas pluviais como fontes alternativas. Verificou-se que cada evaporador produz 4,8 litros/água/hora, considerando 10 horas de uso diário, o volume acumulado chegaria a 48 litros/dia por aparelho que multiplicado pelo total de 137 unidades chega-se ao volume diário de 4.298 litros o que representa 77,72% da demanda das descargas sanitárias que é de 5.530 litros/dia. Em relação ao aproveitamento de águas pluviais, a previsão de acumulação refere-se a 10% da área do terreno que multiplicado pelo índice de 0,05 e pela retenção de 1 hora, obtém o volume de 14,8 m3 . Pretende-se com essa prática, alcançar uma redução significativa do volume de água potável, hoje utilizada praticamente para a realização de todas as atividades, contribuindo assim para uma obra mais sustentável, minimizando os impactos ambientais causados pela construção.

  12. Corrections to air kerma rate measurements of 125I brachytherapy sources to free space conditions

    Shipley, D.R.; Duane, S.

    1994-05-01

    Air kerma rate measurements have been made between 40 cm and 100 cm from one of a set of 125 I reference sources within the facilities of Amersham International plc. Monte Carlo techniques have been used to calculate the air kerma rate components over the same range of distances from this source. After comparing the calculated data with measurements, the compliance of the data with the inverse square law was investigated, and corrections were derived to obtain the air kerma rate at 1 m in free space from each source. Simulations of the experimental setup with an isotropic monoenergetic point source close to the effective energy of 125 I were found to reproduce the air kerma rate measurements reasonably accurately, and indicated that the contribution due to scattered photons was significant. The overall correction (which is defined as the product of individual corrections for chamber size effect, air attenuation and radiation scatter) required to the inverse square law to obtain the air kerma rate at 1 m in free space was found to be 0.981, 0.984 and 0.980, respectively, for air kerma rate measurements at 40 cm, 60 cm and 100 cm from the 125 I reference source. The total uncertainty in these corrections was estimated to be 0.88% at the 1σ level. (author)

  13. Efeito do 1-metilciclopropeno na conservação de maçãs 'Royal Gala' em ar refrigerado e atmosfera controlada Effects of 1-methylcyclopropene on 'Royal Gala' apples stored in refrigerated air and controlled atmosphere

    Adriana Regina Corrent

    2004-08-01

    Full Text Available Maçãs 'Royal Gala', colhidas em dois estádios de maturação, foram tratadas com 1-MCP (1-metilciclopropeno nas concentrações de 0; 625 e 1250 nL.L-1, durante 48 horas, à temperatura de 20 ± 2 ºC. Após este tratamento, foram armazenadas em dois diferentes sistemas: em atmosfera controlada à temperatura de 0 ± 0,5 ºC, 2,1 a 2,3 kPa de CO2 , 1,8 a 2,0 kPa de O2 e umidade relativa de 95 ± 5 %, durante 9 meses. Em ar refrigerado a 0,5 ± 0,5 ºC e 95 ± 5 % de umidade relativa, durante 8 meses. As análises realizadas demonstraram a eficiência do 1-MCP em controlar a maturação das frutas durante o armazenamento em ambas as condições e pontos de colheita. A aplicação do 1-MCP reduziu drasticamente a produção de etileno, diminuiu a perda de firmeza, além de preservar a acidez total titulável.In the present work were evaluated the effects of 1-MCP on 'Royal Gala' apples stored in refrigerated air and controlled atmosphere. 'Royal Gala' apples were harvested at two ripeness stages and treated with 1-methylcyclopropene (1-MCP using two concentrations 625 and 1250 nL.L-1 which were applied during 48 hours at temperature of 20 ± 2 ºC. The control fruit was only kept in air. After the treatments the apples were stored in either controlled atmosphere 2,1 to 2,3 kPa CO2, 1,8 to 2,0 kPa O2 and 95 ± 0,5 % of relative humidity for 9 months at 0 ± 0,5 ºC or in refrigerated air storage at 0,5 ± 0,5 ºC and 95 ± 0,5 % of relative humidity, for 8 months. The 1-MCP applications on apples in both storages and ripening stages reduced dramatically the ethylene production. Pulp firmness losses and titratable acidity were also significanthy higher compared to control fruit.

  14. Assessment of arsenic toxicity in spiked soils and water solutions by the use of bioassays Evaluación de la toxicidad del arsénico en suelos y soluciones contaminadas mediante el uso de bioensayos Avaliação da toxicidade de arsénio em solos contaminados e em soluções aquosas com recurso a bioensaioS

    Francisco José Martín Peinado

    2012-11-01

    concentración efectiva de arsénico que reduce un 50% la variable respuesta (EC50 fue de 1,52 ppm para el ensayo con L. sativa y 4,98 ppm para el ensayo con V. fischeri, indicando que el bioensayo con L. sativa fue más sensible a las concentraciones de arsénico en las soluciones contaminadas.O Arsénio (As constitui um grave problema ambiental devido à sua ampla utilização e elevado potencial tóxico . Para além disso, este elemento tende a acumular-se nos solos devido à sua baixa mobilidade. Neste estudo, fez-se uma avaliação do potencial de toxicidade do As em solos e soluções aquosas de amostras laboratoriais contaminadas com este elemento, recorrendo a bioensaios com Vibrio fischeri e Lactuca sativa. Os solos contaminados com 100 ppm de arsénio registaram uma redução da solubilidade do As na solução do solo ao longo do tempo, enquanto que para os períodos de incubação mais longos (8 semanas, as respostas à toxicidade em todas as amostras neste tipo de bioensaios foi insignificante. Em soluções aquosas contaminadas com concentrações crescentes de arsénio (0, 0,1, 1, 10, 12.5, 25, 50, and100 ppm As, observaram-se reduções significativas no elongamento das raízes e na luminiscênciar espetivamente na alface e nos bioensaios com bactérias. A concentração efetiva de As (EC50 apresentou os valores de 1,52 ppm para a L. sativa e 4,98 ppm para a V. fischeri, o que indica que os bioensaios com L. sativa foram mais sensíveis às concentrações de As nas soluções contaminadas.

  15. PADRÕES DE VARIABILIDADE EM VAZÕES AFLUENTES A USINAS HIDRELÉTRICAS E ASSOCIAÇÕES COM MASSAS DE AR

    Erick Meira de Oliveira

    2018-03-01

    Full Text Available DOI: 10.12957/cadest.2017.31363 Os padrões fluviais brasileiros são sensíveis a diversos fatores geográficos e atmosféricos locais e de grande escala, sofrendo variações consideráveis ao longo da extensão territorial do País. Apesar da vasta gama de informações hoje disponíveis sobre esses fatores, sabe-se que a vazão de rios brasileiros possui relações significativas com padrões climáticos bem característicos, podendo se substituir, por vezes, uma quantidade expressiva de elementos por amostras que concentrem a maior parte das informações estatísticas da base de dados. Nesse contexto, este trabalho buscou identificar, por meio da aplicação de diferentes técnicas de análise estatística multivariada, características comuns a diferentes rios brasileiros, utilizando como informação principal suas vazões. Os resultados sugerem que os comportamentos de grande parte dos rios brasileiros usados para aproveitamento hidrelétrico podem ser caracterizados por um conjunto pequeno de padrões bem definidos, que traduzem os diferentes regimes de massas de ar aos quais o território brasileiro está submetido. Palavras-chave: Análise Multivariada; Vazões de Rios; Massas de ar.

  16. ASPECTOS EPIDEMIOLÓGICOS DE UM FOCO DE TUNGÍASE (Tunga penetrans, SIPHONAPTERA EM UM SISTEMA INTENSIVO DE SUÍNOS CRIADOS AO AR LIVRE EPIDEMIOLOGICAL ASPECTS OF A FOCUS OF Tunga penetrans INFESTATION IN OUTDOOR PIG PRODUCTION

    Osmar Antônio Dalla Costa

    2007-09-01

    Full Text Available

    O sistema intensivo de produção de suínos criados ao ar livre (SISCAL é caracterizado por manter os suínos em piquetes com cobertura vegetal, nas fases de reprodução, maternidade e creche, cercados com tela e/ou fios de arame eletrificado. Este trabalho teve por objetivo relatar aspectos epidemiológicos de um foco de tungíase ocorrido em um SISCAL. Foram examinados clinicamente 72 animais, sendo 6 cachaços, 9 fêmeas lactantes, 13 em gestação e 6 em cobrição, 20 leitões lactantes e 34 leitões desmamados e transferidos para unidades de terminação. Verificou-se que nenhum dos cachaços estava infestado (granja 1= 48 e que em 50% do total de fêmeas examinadas ocorreram lesões com maior freqüência nos tetos, o que nas porcas lactantes deu origem à agalaxia por obstrução do canal galactóforo ocasionando involução da glândula mamária. Em 90% dos leitões lactantes constatou-se dificuldade de locomoção causada pela presença do parasito na região plantar do casco e 25% apresentavam, além disto, lesões no jarrete. Dos leitões desmamados transferidos para unidades de terminação em confinamento, com 40-47 dias (granja 2, n=24 e com 70 dias (granja 3, n= 10 de idade 100% e 80%, respectivamente. ainda apresentavam lesões semelhantes às observadas em leitões lactantes. Conclui-se que a tungíase pode afetar suínos criados ao ar livre podendo causar agalaxia em porcas lactantes e dificuldade de locomoção em leitões lactantes e desmamados.

    PALAVRAS-CHAVE: Tunga penetrans; bicho-de-pé; tungíase; sistema intensivo de suínos criados ao ar livre; agalaxia.

    The outdoors intensive-type pig production is characterized by maintaining swine during

  17. A poluição do ar em ambientes internos e a síndrome dos edifícios doentes Air pollution in internal environments and sick building syndrome

    Waldir Nagel Schirmer

    2011-08-01

    Full Text Available A Qualidade do Ar Interno (QAI surgiu como ciência a partir da década de 70 com a crise energética e a consequente construção dos edifícios selados (desprovidos de ventilação natural, principalmente nos países desenvolvidos, e se destacou após a descoberta de que a diminuição das taxas de troca de ar nesses ambientes era a grande responsável pelo aumento da concentração de poluentes no ar interno. Admite-se que a ventilação seja um dos principais fatores que interferem na qualidade do ar interno e que os próprios ocupantes dos edifícios contribuem substancialmente com a poluição destes ambientes através de suas atividades. Sabe-se ainda que a má qualidade do ar interno está associada a doenças (como tosse, rinite, alergia, etc. e à Síndrome dos Edifícios Doentes (SED. Para amostragem de substâncias gasosas no ar de ambientes internos dispõe-se de diversas metodologias, sendo as principais: sistemas passivos de monitoramento, sistemas ativos e automáticos. Para a efetiva promoção de um ambiente saudável, deve-se conciliar a aplicação de legislações específicas com pesquisas e conscientização dos ocupantes dos edifícios. Essa revisão objetiva relacionar os diferentes contaminantes encontrados em ambientes internos, seus efeitos à saúde humana e suas metodologias de amostragem.Indoor Air Quality (IAQ emerged as a science from the 1970s onwards with the energy crisis and the subsequent construction of sealed buildings (without natural ventilation. This mainly occurred in developed countries and it soon came to public attention that lower levels of air exchange in these environments was the main culprit for the increase in concentration of indoor air pollutants. It is common knowledge that ventilation is one of the principal factors that interfere with air quality in indoor environments and that the occupants contribute to the pollution of these environments with their activities. Furthermore, poor indoor

  18. Educação ao ar livre pela aventura: o aprendizado de valores morais em expedições à natureza Education outdoors through adventure: learning moral values in nature expeditions

    Flavio Theodor Kunreuther

    2012-06-01

    Full Text Available A educação ao ar livre, por meio de cursos no formato expedição, ainda acontece de forma tímida no Brasil. Entende-se por expedição uma experiência educacional contínua, de múltiplos dias, em que alunos e instrutores aventuram-se em um trajeto em área remota da natureza de forma autossuficiente. O presente estudo analisa os cursos desse tipo. Por meio de entrevistas e questionários semiestruturados, investigou-se a aprendizagem dos alunos segundo suas próprias percepções e as dos educadores da instituição, com ênfase no desenvolvimento moral do indivíduo. Como parte do estudo de caso sobre um aluno adolescente participante de um dos cursos, entrevistou-se também uma psicóloga que coordena um abrigo para menores. Os resultados encontrados indicam que os cursos de educação ao ar livre caracterizam-se por experiências que estimulam trabalhos em grupo, debates sobre justiça e solidariedade, e reflexões sobre valores e princípios como coragem, esforço pessoal, disciplina, respeito e superação de limites. Os resultados também indicam que tal proposta educacional aufere experiências sensíveis e de conexão do ser humano com a natureza. Muito embora haja potencial educacional para a educação ao ar livre, a atuação do educador perante seus alunos é fundamental para que as experiências sejam física e psicologicamente seguras, alcancem seus potenciais pedagógicos de desenvolvimento da moralidade e ajudem as pessoas a desenvolverem uma consciência ambiental, manifestada por meio de ações concretas ao retornarem dos cursos para suas comunidades.Open air education through courses organized as expeditions is still incipient in Brazil. We understand an expedition as a continued educational experience taking several days in which students and instructors venture into a remote natural area in a self-sufficient way. The present study analyzes courses of this type. Using interviews and semi-structured questionnaires, it

  19. The IPEM code of practice for determination of the reference air kerma rate for HDR 192Ir brachytherapy sources based on the NPL air kerma standard

    Bidmead, A M; Sander, T; Nutbrown, R F; Locks, S M; Lee, C D; Aird, E G A; Flynn, A

    2010-01-01

    This paper contains the recommendations of the high dose rate (HDR) brachytherapy working party of the UK Institute of Physics and Engineering in Medicine (IPEM). The recommendations consist of a Code of Practice (COP) for the UK for measuring the reference air kerma rate (RAKR) of HDR 192 Ir brachytherapy sources. In 2004, the National Physical Laboratory (NPL) commissioned a primary standard for the realization of RAKR of HDR 192 Ir brachytherapy sources. This has meant that it is now possible to calibrate ionization chambers directly traceable to an air kerma standard using an 192 Ir source (Sander and Nutbrown 2006 NPL Report DQL-RD 004 (Teddington: NPL) http://publications.npl.co.uk). In order to use the source specification in terms of either RAKR, .K R (ICRU 1985 ICRU Report No 38 (Washington, DC: ICRU); ICRU 1997 ICRU Report No 58 (Bethesda, MD: ICRU)), or air kerma strength, S K (Nath et al 1995 Med. Phys. 22 209-34), it has been necessary to develop algorithms that can calculate the dose at any point around brachytherapy sources within the patient tissues. The AAPM TG-43 protocol (Nath et al 1995 Med. Phys. 22 209-34) and the 2004 update TG-43U1 (Rivard et al 2004 Med. Phys. 31 633-74) have been developed more fully than any other protocol and are widely used in commercial treatment planning systems. Since the TG-43 formalism uses the quantity air kerma strength, whereas this COP uses RAKR, a unit conversion from RAKR to air kerma strength was included in the appendix to this COP. It is recommended that the measured RAKR determined with a calibrated well chamber traceable to the NPL 192 Ir primary standard is used in the treatment planning system. The measurement uncertainty in the source calibration based on the system described in this COP has been reduced considerably compared to other methods based on interpolation techniques.

  20. Preferência manual na ação de alcançar em bebês em função da localização espacial do alvo Infants' manual preference in reaching regarding spatial target location

    Rosana Machado Souza

    2011-01-01

    Full Text Available Preferência manual em bebês de 5 meses de idade foi avaliada em tarefas de alcançar alvos estáticos posicionados na linha média, à direita e à esquerda com referência a coordenadas egocêntricas. A análise da frequência de uso das mãos indicou direção e magnitude de preferência manual diversificadas entre os bebês. Foi observado que os bebês realizaram predominantemente alcances ipsilaterais para alvos posicionados lateralmente. Para alcances na linha média a frequência de uso foi semelhante entre as mãos direita e esquerda. Os resultados sugerem que nessa fase do desenvolvimento a preferência manual para o alcançar é alterada pela posição dos objetos no espaço.Manual preference of 5-month-old infants was evaluated in tasks of reaching static targets positioned on the midline, at the left and right, regarding egocentric coordinates. Frequency analysis of using the hands pointed out to diversified direction and magnitude of manual preference among infants. It was observed that they predominantly made ipsilateral reaches toward targets laterally positioned. Frequency of using the right and left hands was similar for targets located at the midline. The results suggest that in this stage of development manual preference is shifted by the spatial position of the objects.

  1. X-rays spectrum and air Kerma during a mammography study

    Ramirez G, J.; Hernandez V, R.; Hernandez D, V. M.; Vega C, H. R.

    2009-10-01

    In this calculation series was modeled the source of electrons, the target and the filter. Using thermoluminescent dosemeters of ZrO 2 +PTFE the air Kerma was measured in five points located on a phantom made with acrylic and water when it was exposed to a X-rays beam produced by electrons of 24 KeV and 10 m A of current that produces a mammography. The air Kerma values at the entrance surface of the phantom were compared with values calculated by Monte Carlo methods. The air Kerma values measured indicate that approximately the five points receive the same air Kerma, what means that the beam is homogeneous, of the Monte Carlo calculations we find that the center receives a greater dose what implies that the beam is not uniform, the explanation of this fact is attributed to was used a simple model in the calculations, nevertheless, the air Kerma average measured at the entrance surface of the phantom was of 0.96 + - 0.03 m G, while the other obtained by the calculations was of 0.96 + - 0.06 mGy, to compare both do not exist significant differences. (author)

  2. Estudo da liga alumínio-zinco como filtração alternativa em aparelhos de raios X odontológicos Study of the aluminum-zinc alloy as an alternative means of filtration in dental X-ray devices

    Claudia Fátima Silva HAITER

    2002-03-01

    Full Text Available O objetivo neste trabalho foi avaliar os efeitos da filtração alternativa da liga alumínio-zinco em aparelhos de raios X odontológicos, em relação ao espectro de energia dos feixes de raios X, a taxa de kerma no ar, o índice de contraste nas radiografias obtidas e a qualidade das imagens radiográficas. Este estudo foi realizado comparando-se o filtro convencional de alumínio com várias espessuras do filtro de liga alumínio-zinco, em diferentes porcentagens do elemento zinco na liga (2%, 3%, 4% e 5%. Foi utilizado um aparelho de raios X odontológico convencional, operando com 60 kVp e 70 kVp, e filmes radiográficos dos grupos D e E de sensibilidade. Foram realizadas radiografias de um "phantom" e de uma escala de densidade de alumínio. Os resultados mostraram que o uso dos filtros de liga Al-Zn resultou em um não-endurecimento dos feixes. A taxa de kerma no ar diminuiu em até 18,53%, sem alteração no contraste das radiografias e a qualidade das imagens teve uma boa aceitação pelos examinadores. A análise dos resultados nos levou a concluir que o filtro de liga Al-Zn 2%, com 1,99 mm de espessura, tensão de 60 kVp, quando usado com filme D, foi o que obteve melhor desempenho, reduzindo a taxa de kerma no ar sem variar o índice de contraste das radiografias, mantendo a qualidade da imagem aceitável para diagnóstico, sem contudo aumentar o tempo de exposição.The aim of this study was to evaluate the effects of alternative filtration with the aluminum-zinc alloy in dental X-ray devices, regarding the energy spectrum, dose, contrast and image quality. This study was carried out comparing the conventional aluminum filter with aluminum-zinc alloy filters of various thicknesses and with different percentages of zinc in the alloy (2, 3, 4 and 5%. A conventional X-ray device operating with 60 and 70 kVp as well as D- and E-speed films were utilized in order to obtain images of a phantom and an aluminum step wedge. The utilization

  3. Poluentes do ar e internações devido a doenças cardiovasculares em São José do Rio Preto, Brasil

    Kátia Cristina Cota Mantovani

    2016-02-01

    Full Text Available Resumo O presente estudo teve como objetivo estimar os efeitos de poluentes ambientais sobre o número de internações por doenças cardiovasculares. Foi um estudo ecológico com dados de internações hospitalares de residentes em São José do Rio Preto, São Paulo, Brasil, com diagnóstico nas categorias de I-00 a I-99, entre 01/10/11 e 30/09/12. Os poluentes analisados foram partículas finas (PM2,5, ozônio, monóxido de carbono, óxido de nitrogênio e dióxido de nitrogênio. Foram estimados pelo modelo CCATT-BRAMS. O uso do modelo aditivo de regressão de Poisson foi utilizado para estimar associação entre a exposição ao PM2,5 e internação por doença cardiovascular. Foram calculados os excessos de internação e os gastos por estas doenças. Observou-se que a exposição ao PM2,5 no quinto dia após a exposição (lag 5 foi significativo para internação e aumentou em 15 ppts segundo incremento de 10µg /m3 na concentração de PM2,5. Foram identificadas 650 internações evitáveis com custos da ordem de R$ 1,9 milhão. Desse modo, foi possível identificar associação entre exposição ao PM2,5 e internações devido a doenças cardiovasculares em cidades de médio porte como São José do Rio Preto fornecendo subsídios aos gestores municipal e regional de Saúde.

  4. SISTEMA COMBINADO DE FLOTAÇÃO POR AR DISSOLVIDO E FILTRAÇÃO ADSORTIVA EM ZEÓLITA PARA TRATAMENTO DE EFLUENTE DE REATOR UASB

    Bruno Oliveira Freitas

    2016-06-01

    Full Text Available RESUMO: Dentre as soluções existentes para efetuar o tratamento de esgoto, o reator anaeróbio do tipo UASB é largamente utilizado no Brasil, porém esta tecnologia apresenta problemas em atender aos limites estabelecidos pela legislação brasileira para lançamento de efluente em termos de nitrogênio amoniacal, fósforo e matéria orgânica, necessitando de pós-tratamento. Diante do potencial para remoção de matéria orgânica e sólidos suspensos pela flotação e da eficiência que a zeólita apresenta na remoção de amônia, a floto-filtração-adsortiva em zeólita pode ser uma promissora alternativa para tratamento deste efluente. Sendo assim, o presente trabalho visou avaliar a eficiência de um sistema de flotação associado à filtração-adsortiva, utilizando zeólita como meio filtrante, para pós-tratamento de efluente de reator UASB. Para tal, foram realizados ensaios de coagulação/floculação, flotação e filtração-adsortiva com um floteste adaptado com filtros adsorventes, utilizando efluente de reator anaeróbio do tipo UASB. Os resultados obtidos neste estudo atenderam aos padrões estabelecidos pela legislação brasileira para lançamento de efluentes em corpos d’água, alcançando 100 % de remoção de nitrogênio amoniacal, permitindo que esse efluente possa ser aproveitado para reuso. Desse modo, o sistema de flotação com a filtração-adsortiva utilizando zeólita como meio filtrante mostrou-se eficiente na remoção de todos os poluentes avaliados. Esta pesquisa teve como principal contribuição a avaliação de alternativa promissora para pós-tratamento de efluente de reator UASB buscando atender as exigências da legislação brasileira e melhorar da qualidade dos efluentes sanitários. ABSTRACT: Among the existing solutions to sewage treatment, the UASB reactor is widely used in Brazil, but this technology has problem to attend the limits established by Brazilian law for discharging of effluent

  5. New remarks on KERMA factors and DPA cross section data in ACE files

    Konno, Chikara; Sato, Satoshi; Ohta, Masayuki; Kwon, Saerom; Ochiai, Kentaro

    2016-01-01

    KERMA factors and DPA cross section data are essential for nuclear heating and material damage estimation in fusion reactor designs. Recently we compared KERMA factors and DPA cross section data in the latest official ACE files of JENDL-4.0, ENDF/B-VII.1, JEFF-3.2 and FENDL-3.0 and it was found out that the KERMA factors and DPA cross section data of a lot of nuclei did not always agree among the nuclear data libraries. We investigated the nuclear data libraries and the nuclear data processing code NJOY and specified new reasons for the discrepancies; (1) incorrect nuclear data and NJOY bugs, (2) huge helium production cross section data, (3) gamma production data format in the nuclear data, (4) no detailed secondary particle data (energy–angular distribution data). These problems should be resolved based on this study.

  6. Air kerma rate estimation by means of in-situ gamma spectrometry: A Bayesian approach

    Cabal, Gonzalo; Kluson, Jaroslav

    2008-01-01

    Full text: Bayesian inference is used to determine the Air Kerma Rate based on a set of in situ environmental gamma spectra measurements performed with a NaI(Tl) scintillation detector. A natural advantage of such approach is the possibility to quantify uncertainty not only in the Air Kerma Rate estimation but also for the gamma spectra which is unfolded within the procedure. The measurements were performed using a 3'' x 3'' NaI(Tl) scintillation detector. The response matrices of such detection system were calculated using a Monte Carlo code. For the calculations of the spectra as well as the Air Kerma Rate the WinBugs program was used. WinBugs is a dedicated software for Bayesian inference using Monte Carlo Markov chain methods (MCMC). The results of such calculations are shown and compared with other non-Bayesian approachs such as the Scofield-Gold iterative method and the Maximum Entropy Method

  7. New remarks on KERMA factors and DPA cross section data in ACE files

    Konno, Chikara, E-mail: konno.chikara@jaea.go.jp; Sato, Satoshi; Ohta, Masayuki; Kwon, Saerom; Ochiai, Kentaro

    2016-11-01

    KERMA factors and DPA cross section data are essential for nuclear heating and material damage estimation in fusion reactor designs. Recently we compared KERMA factors and DPA cross section data in the latest official ACE files of JENDL-4.0, ENDF/B-VII.1, JEFF-3.2 and FENDL-3.0 and it was found out that the KERMA factors and DPA cross section data of a lot of nuclei did not always agree among the nuclear data libraries. We investigated the nuclear data libraries and the nuclear data processing code NJOY and specified new reasons for the discrepancies; (1) incorrect nuclear data and NJOY bugs, (2) huge helium production cross section data, (3) gamma production data format in the nuclear data, (4) no detailed secondary particle data (energy–angular distribution data). These problems should be resolved based on this study.

  8. Standardization of iridium-192 coiled source in terms of air kerma output

    Shanta, A.; Unnikrishnan, K.; Tripathi, U.B.; Kannan, A.; Iyer, P.S.

    1996-01-01

    ICRU (1985) recommended that the output of gamma ray brachytherapy sources should be specified in terms of reference air kerma rate, defined as the kerma rate to air in air at a reference distance of 1 meter, perpendicular to the long axis of the source, corrected for air attenuation and scattering. As these measurements are difficult to carry out in the routine clinical use, it is the common practice to calibrate the re-entrant ionization chamber with respect to open air measurements and use the re-entrant chamber for routine measurements. This paper reports on the measurements carried out to correlate the nominal activity and air kerma rate of 192 Ir wire sources supplied by the Board of Radiation and Isotope Technology, Department of Atomic Energy. (author). 3 refs, 1 tab

  9. Standardization of iridium-192 coiled source in terms of air kerma output

    Shanta, A; Unnikrishnan, K; Tripathi, U B; Kannan, A; Iyer, P S [Bhabha Atomic Research Centre, Bombay (India)

    1996-08-01

    ICRU (1985) recommended that the output of gamma ray brachytherapy sources should be specified in terms of reference air kerma rate, defined as the kerma rate to air in air at a reference distance of 1 meter, perpendicular to the long axis of the source, corrected for air attenuation and scattering. As these measurements are difficult to carry out in the routine clinical use, it is the common practice to calibrate the re-entrant ionization chamber with respect to open air measurements and use the re-entrant chamber for routine measurements. This paper reports on the measurements carried out to correlate the nominal activity and air kerma rate of {sup 192}Ir wire sources supplied by the Board of Radiation and Isotope Technology, Department of Atomic Energy. (author). 3 refs, 1 tab.

  10. Conversion of Airborne Gamma ray Spectra to Ground Level Air Kerma Rates

    Bargholz, Kim; Korsbech, Uffe C C

    1997-01-01

    A new method for relating airborne gamma-ray spectra to dose rates and kerma rates at ground level is presented. Dependent on flying altitude 50 m to 125 m the method gives correct results for gamma energies above 250 keV respective 350 keV. At lower energies the method underestimate the dose...... or kerma rates; by having a large fraction of the ground level gamma-rays at energies below 350 keV special care should be taken at an interpretation of the results....

  11. 40Ar/39Ar dating of pyrite

    York, D.; Masliwec, A.; Kuybida, P.; Hanes, J.A.; Hall, C.M.; Kenyon, W.J.; Spooner, E.T.C.; Scott, S.D.

    1982-01-01

    To overcome difficulties encountered in the customary method of determining the age of mineralization of sulphide ore deposits by analysing silicate material, the sulphide minerals themselves have been examined to see if they contained sufficient potassium and argon for 40 Ar/ 39 Ar age determination. Initial results indicate that this is the case for pyrite from the Geco ore body in northwestern Ontario, Canada. (U.K.)

  12. Tendências anuais e sazonais nos extremos de temperatura do ar e precipitação em campina grande - pb

    Leydson Galvíncio Dantas

    2015-12-01

    Full Text Available RESUMO Devido à rápida expansão urbana e potencial turístico da região, o objetivo deste estudo foi a obtenção da distribuição temporal dos índices de extremos climáticos dependentes de dados diários de temperatura e precipitação, definido pela OMM, para o período de 1975 a 2011, e utilizando os testes estatísticos não paramétricos obter a magnitude das tendências dos referidos índices para a cidade de Campina Grande - PB. Os resultados mostram que as temperaturas mínimas e máxima diárias têm aumentado gradativamente ao longo das últimas décadas, apresentando tendências sazonais crescentes ao longo dos anos e que as temperaturas mínimas tiveram maior aumento. O número de dias e noites quentes por ano tem aumentado, proporcionando assim uma redução significativa dos dias e noites frias. Foi observado que as temperaturas mínimas e máximas apresentam maiores tendências de aumento nas estações do outono e primavera, respectivamente. Baseado nos índices extremos de precipitação, mesmo sem significância estatística, foi observado que as chuvas intensas tendem a aumentar, ocorrendo em um período menor de tempo.

  13. Avaliação da qualidade do ar em um polo produtor de ferro-gusa Evaluation of the air quality in a pig iron production pole

    Vanusa Maria Feliciano Jacomino

    2009-12-01

    Full Text Available Este estudo se iniciou com a realização de um inventário das fontes de emissão de material particulado existentes no município de Sete Lagoas (MG. Com base nessas informações e nos parâmetros meteorológicos e topográficos da região, foi feita a seleção dos pontos de maior concentração de material particulado inalável (MP10 usando o modelo ISC3. Um dos pontos identificados se situa na área central do município. Nesse local foram coletadas várias amostras de material particulado (MP para determinação das composições mineralógica e elementar das partículas de aerossol (MP10. A calcita foi o mineral mais abundante (> 30% e o Na, Ba e o Fe foram os elementos-traço presentes em maior proporção no material coletado. A análise de fatores principais mostrou que a ressuspensão de poeira de solo e as atividades industriais são os maiores contribuintes de emissão do MP naquela área.This study started with the inventory of the main particulate emission sources of Sete Lagoas city, Minas Gerais, Brazil. Based on this data and on local meteorological and topographic parameters, the selection of the highest points of inhalable particulate (PM10 concentrations was carried out using the ISC3 model. One of the identified points is situated on the central area of the city. Several samples of particulate matter (PM were collected in that site for the determination of the mineralogical and elemental composition of the aerosol particles (PM10. Calcite was the most abundant mineral (> 30%, and Na, Ba and Fe were the trace elements presented in larger proportion in the collected material. The analysis of the main factors showed that resuspension of soil dust and industrial sources were the largest contributors of PM emissions in that area.

  14. X-Rays spectrum and air kerma during a mammography study;Espectro de los rayos X y kerma en aire durante un estudio mamografico

    Ramirez G, J. [Instituto Nacional de Estadistica Geografia e Informatica, Direccion General de Innovacion y Tecnologia de Informacion, Av. Heroes de Nacozari Sur No. 2301, Fracc. Jardines del Parque, 20276 Aguascalientes (Mexico); Hernandez V, R.; Chacon R, A.; Vega C, H. R., E-mail: ramirezgonzalezjaime@yahoo.com.m [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2009-10-15

    The X-rays spectrum produced in a mammography has been calculated by means of Monte Carlo methods. In this calculation series it is modeled the electrons source, the target and the filter. The spectra were calculated for an energy of the electrons of 28 keV and for targets of W, Mo and Rh. The calculations extended to analyze the effect that produces the filters inclusion in the spectra; the spectra of W-A1, Rh-Rh, Mo-Mo, Mo-Rh and Mo-Be were calculated this way. Using thermoluminescent dosemeters of ZrO{sub 2}+PTFE the air kerma was measured in five points located on a phantom made with acrylic and water when it is was exposed to a X-rays beam produced by electrons of 24 keV and 10 m A of current that it produces a mammography. The values of the air kerma on the entrance surface of the phantom were compared with the calculated values by means of Monte Carlo methods. The calculated spectra present a continuous component and another discreet and its form is similar to the reported spectra in the literature. The filters inclusion allows the elimination of the low energy photons that do not have utility in the obtaining of the mammography image and only they contribute to deposit a dose in the mamma. The values of the measured air kerma indicate that the five points receive the same air kerma approximately, what means that the beam is homogeneous, of the Monte Carlo calculations we find that the center receives a bigger dose which implies that the beam is not uniform, the explanation on this fact it is attributed to that a simple model was used in the calculations, nevertheless, the average of the air kerma measured on the entrance surface of the phantom was of 0.96 +- 0.03 m G, while the obtained by means of the calculations was of 0.96 +- 0.06 mGy, when comparing both significant differences do not exist. (Author)

  15. Resistência parcial à necrose dos frutos em genótipos de café arábica Partial resistance to fruit necrosis in arabic coffee genotypes

    Gustavo Hiroshi Sera

    2009-01-01

    Full Text Available Neste trabalho, objetivou-se identificar em genótipos de café arábica (Coffea arabica L. fontes de resistência à necrose de frutos em condições de campo. As variáveis resistência à necrose de frutos ("NF", quantidade média de frutos por nó produtivo ("FN" e índice de luminosidade dentro da copa da planta ("LUM" foram avaliadas em ensaio de campo no IAPAR (Londrina, em dezembro de 2004, em cafeeiros com três anos de idade. Foi avaliada a variável "NF", atribuindo notas de 1 a 5 sendo 1 para plantas com 0 % a 5 % de frutos necrosados. "FN" foi avaliada seguindo uma escala de notas de 1 a 5, onde 1 representa plantas com 0 a 3 frutos/ nó e nota 5 com mais do que 15 frutos/ nó. A avaliação da variável "LUM" foi visual e seguiu as notas de 1 a 5, onde 1 representa plantas com pouca luminosidade dentro da copa da planta. Dos 19 genótipos avaliados, 2 apresentaram moderada resistência, 7 moderada suscetibilidade, 5 suscetíveis e 5 altamente suscetíveis. As cultivares Obatã IAC 1669-20 e Catucaí Vermelho 4-79 apresentaram o melhor nível de resistência parcial de campo, ou seja, com moderada resistência à necrose de frutos associada ao Colletotrichum spp.The aim of this research was to identify in Coffea arabica L. coffee genotypes resistance sources to fruit necrosis in field conditions. The variables fruit necrosis ("NF", fruits per productive nodes average ("FN" and luminosity index inside of the plant canopy ("LUM" were evaluated in field assay at IAPAR (Londrina, in December 2004 on three years old coffee trees. The "NF" variable were evaluated attributing scores from 1 to 5, where score 1 represented plants with 0 to 5 % of necrosed fruits. "FN" were evaluated following a score scale from 1 to 5, where score 1 represented plants with 0 to 3 fruits/ node and score 5 with more than 15 fruits/ node. The evaluation of the variable "LUM" was visual and followed the scores from 1 to 5, where score 1 represented plants with

  16. Status and evaluation methods of JENDL fusion file and JENDL PKA/KERMA file

    Chiba, S.; Fukahori, T.; Shibata, K.; Yu Baosheng; Kosako, K.

    1997-01-01

    The status of evaluated nuclear data in the JENDL fusion file and PKA/KERMA file is presented. The JENDL fusion file was prepared in order to improve the quality of the JENDL-3.1 data especially on the double-differential cross sections (DDXs) of secondary neutrons and gamma-ray production cross sections, and to provide DDXs of secondary charged particles (p, d, t, 3 He and α-particle) for the calculation of PKA and KERMA factors. The JENDL fusion file contains evaluated data of 26 elements ranging from Li to Bi. The data in JENDL fusion file reproduce the measured data on neutron and charged-particle DDXs and also on gamma-ray production cross sections. Recoil spectra in PKA/KERMA file were calculated from secondary neutron and charged-particle DDXs contained in the fusion file with two-body reaction kinematics. The data in the JENDL fusion file and PKA/KERMA file were compiled in ENDF-6 format with an MF=6 option to store the DDX data. (orig.)

  17. Studies on effective atomic number, electron density and kerma for some fatty acids and carbohydrates

    Manohara, S.R.; Hanagodimath, S.M.; Gerward, Leif

    2008-01-01

    The effective atomic number, Z(eff), the effective electron density, N-el, and kerma have been calculated for some fatty acids and carbohydrates for photon interaction in the extended energy range from 1 keV to 100 GeV using an accurate database of photon-interaction cross sections and the WinXCo...

  18. Review of the research and application of KERMA factor and DPA cross section

    1991-03-01

    The data for recoil atom spectra, KERMA factor and displacement cross sections from neutron-induced reactions are calling increasing interest for applications to the study of radiation damage, calculation of heat generation in reactor, neutron therapy and biological research. PKA spectra sub-working group was recently established in Japanese Nuclear Data Committee as a part of developing JENDL Special Purpose Data Files. Current status of the data and various features of application of the KERMA-related problems were reviewed and discussed at the first meeting of the sub-working group. Present report is a compilation of the items presented at the meeting, covering a brief review of the existing research and the data, method of calculation, the KERMA factor data in neutron therapy, the deduction of KERMA factor of C-12 from neutron reaction measurement and analysis, the data base for radiation damage, the damage simulation calculation, and the method of storaging the evaluated data in ENDF/B-VI format. (author)

  19. KERMA-based radiation dose management system for real-time patient dose measurement

    Kim, Kyo-Tae; Heo, Ye-Ji; Oh, Kyung-Min; Nam, Sang-Hee; Kang, Sang-Sik; Park, Ji-Koon; Song, Yong-Keun; Park, Sung-Kwang

    2016-07-01

    Because systems that reduce radiation exposure during diagnostic procedures must be developed, significant time and financial resources have been invested in constructing radiation dose management systems. In the present study, the characteristics of an existing ionization-based system were compared to those of a system based on the kinetic energy released per unit mass (KERMA). Furthermore, the feasibility of using the KERMA-based system for patient radiation dose management was verified. The ionization-based system corrected the effects resulting from radiation parameter perturbations in general radiography whereas the KERMA-based system did not. Because of this difference, the KERMA-based radiation dose management system might overestimate the patient's radiation dose due to changes in the radiation conditions. Therefore, if a correction factor describing the correlation between the systems is applied to resolve this issue, then a radiation dose management system can be developed that will enable real-time measurement of the patient's radiation exposure and acquisition of diagnostic images.

  20. Determination of air kerma standard of high dose rate 192Ir brachytherapy source

    Pires, E.J.; Alves, C.F.E.; Leite, S.P.; Magalhaes, L.A.G.; David, M.G.; Almeida, C.E. de

    2015-01-01

    This paper presents the methodology developed by the Laboratorio de Ciencias Radiologicas and presently in use for determining of the air kerma standard of 192 Ir high dose rate sources to calibrate well-type chambers. Uncertainty analysis involving the measurements procedure are presented. (author)

  1. Seasonal variation of air kerma in the 'Vulcano Porto' area (Aeolian Islands, Italy)

    Bellia, S.; Basile, S.; Brai, M.; Hauser, S.; Puccio, P.; Rizzo, S.

    2001-01-01

    Air kerma was measured in the 'Vulcano Porto' area of the Vulcano Island, belonging to the Aeolian Islands, in the Mediterranean Sea. Measurements were carried out using thermoluminescence dosimeters. The relationship between observed dose values and source lithology has been assessed. Data show a seasonal variation due to weather conditions but also probably related to features of the soils, making the variation more evident

  2. Seasonal variation of air kerma in the "Vulcano Porto" area (Aeolian Islands, Italy).

    Bellia, S; Basile, S; Brai, M; Hauser, S; Puccio, P; Rizzo, S

    2001-04-01

    Air kerma was measured in the "Vulcano Porto" area of the Vulcano Island, belonging to the Aeolian Islands, in the Mediterranean Sea. Measurements were carried out using thermoluminescence dosimeters. The relationship between observed dose values and source lithology has been assessed. Data show a seasonal variation due to weather conditions but also probably related to features of the soils, making the variation more evident.

  3. Measurement of the tissue to A-150 tissue equivalent plastic kerma ratio at two p(66)Be neutron therapy facilities

    Langen, K M; Binns, P J; Schreuder, A N; Lennox, A J; Deluca, P M Jr.

    2003-01-01

    The ICRU tissue to A-150 tissue equivalent plastic kerma ratio is needed for neutron therapy dosimetry. The current ICRU protocol for neutron dosimetry recommends using a common conversion factor of 0.95 at all high-energy neutron therapy facilities. In an effort to determine facility specific ICRU tissue to A-150 plastic kerma ratios, an experimental approach was pursued. Four low pressure proportional counters that differed in wall materials (i.e. A-150, carbon, zirconium and zirconium-oxide) were used as dosimeters and integral kerma ratios were determined directly in the clinical beam. Measurements were performed at two p(66)Be facilities: iThemba LABS near Cape Town and Fermilab near Chicago. At the iThemba facility the clinical neutron beam is routinely filtered by a flattening and hardening filter combination. The influence of beam filtration on the kerma ratio was evaluated. Using two recent gas-to-wall dose conversion factor (r m,g value) evaluations a mean ICRU tissue to A-150 plastic kerma ratio of 0.93 ± 0.05 was determined for the clinical beam at iThemba LABS. The respective value for the Fermilab beam is 0.95 ± 0.05. The experimentally determined ICRU tissue to A-150 plastic kerma ratios for the two clinical beams are in agreement with theoretical evaluations. Beam filtration reduces the kerma ratio by 3 ± 2%

  4. Measured neutron carbon kerma factors from 14.1 MeV to 18 MeV

    Deluca, P.M.; Barschall, H.H.; McDonald, J.C.

    1985-01-01

    For A-150 tissue-equivalent plastic, the total neutron kerma is dominated by the hydrogen kerma. Tissue kerma is inferred with reasonable accuracy by normalization to the kerma factor ratio between tissue and A-150 plastic. Because of the close match in the hydrogen abundance in these materials, the principal uncertainty is due to the kerma factors of carbon and oxygen. We have measured carbon kerma factor values of 0.183+-0.015 10 -8 cGy cm 2 and 0.210+-0.016 10 -8 cGy cm 2 at 14.1-MeV and 15-MeV neutron energy, respectively. A preliminary value of 0.297+-0.03 10 -8 cGy cm 2 has been determined at 17.9 MeV. A recent microscopic cross section measurement of the (n,n'3α) reaction in carbon at 14.1-MeV energy gives a kerma factor of 0.184+-0.019 10 -8 cGy cm 2 in agreement with the present result

  5. Measured neutron carbon kerma factors from 14.1 MeV to 18 MeV

    Deluca, P.M. Jr.; Barschall, H.H.; Haight, R.C.; McDonald, J.C.

    1984-01-01

    For A-150 tissue-equivalent plastic, the total neutron kerma is dominated by the hydrogen kerma. Tissue kerma is inferred with reasonable accuracy by normalization to the kerma factor ratio between tissue and A-150 plastic. Because of the close match in the hydrogen abundance in these materials, the principal uncertainty is due to the kerma factors of carbon and oxygen. We have measured carbon kerma factor values of 0.183 +- 0.015 10 -8 cGy cm 2 and 0.210 +- 0.16 10 -8 cGy cm 2 at 14.1-MeV and 15-MeV neutron energy, respectively. A preliminary value of 0.297 +- 0.03 10 -8 cGy cm 2 has been determined at 17.9 MeV. A recent microscopic cross section measurement of the (n,n'3α) reaction in carbon at 14.1-MeV energy gives a kerma factor of 0.184 +- 0.019 10 8 cGy cm 2 in agreement with the present result. 9 refs., 4 figs., 2 tabs

  6. Funcionalidade da oleoresina de páprica microencapsulada em goma-arábica e amido de arroz/gelatina Functionality of microencapsulated paprika oleoresin in arabic gum and rice starch/gelatin

    Andréa Barbosa Santos

    2006-02-01

    Full Text Available O objetivo deste trabalho foi avaliar a funcionalidade da oleoresina de páprica microencapsulada em goma-arábica e amido de arroz/gelatina, incorporada nos sistemas-modelo bolo e gel de gelatina. Avaliou-se a cor por meio de medida instrumental e aceitação sensorial por atributos de aparência e aceitação global. O pigmento encapsulado solubilizou-se, tingiu e se distribuiu uniformemente nos bolos, os quais apresentaram boa aceitação global. Nos géis, a goma apresentou desempenho superior ao amido/gelatina quanto à aparência, porém, todos os tratamentos obtiveram baixa aceitação global. A presença da oleoresina microencapsulada não interferiu negativamente no sabor, aroma ou textura dos sistemas analisados.The objective of this work was to evaluate the functionality of microencapsulated paprika oleoresin in arabic gum and rice starch/gelatin incorporated into the model systems: cake and gelatin gel. The systems were evaluated by instrumental color and consumer test based on the appearance and global acceptance attributes. The encapsulated pigment successfully dyed the cakes as well as was uniformly distributed into the products, showing good sensory acceptance. In the gels, a superior performance was obtained when using arabic gum, however all treatments applied for gels showed low global sensory acceptance. The presence of microencapsulated paprika oleoresin had no negative effect on taste, flavor or texture of analyzed systems.

  7. O papel estratégico de cidades gêmeas no controle de mercadorias em regiões de fronteira no contexto do MERCOSUL: Uruguaiana (BR e Paso de los Libres (AR

    Heleniza Ávila Campos

    2016-12-01

    Full Text Available O território fronteiriço, enquanto espaço potencial para projetos de desenvolvimento compartilhados entre países, apresenta, na realidade política latino-americana, claras limitações de integração. Mesmo assim, os interesses comerciais regionais apontam para uma necessária revisão dos limites e barreiras ali existentes. Neste sentido, o Mercado Comum do Sul - MERCOSUL tem se constituído, desde 1991 (ano de sua criação, em um bloco de países sulamericanos que visa a ampliar a circulação de bens, serviços e pessoas. No entanto, os projetos regionais de caráter econômico conflituam-se com a realidade desigual de suas cidades gêmeas, as quais não possuem infraestrutura nem investimentos sociais para tais dinâmicas. No contexto da América do Sul, mais especificamente da Bacia Platina, destacam-se as cidades gêmeas de Uruguaiana (BR e Paso de los Libres (AR, que têm representado um importante papel no controle de fluxos de mercadorias e pessoas, de acordo com demandas comerciais, embora suas condições de desenvolvimento sejam precárias. O artigo se propõe a discutir o papel das cidades gêmeas como nós funcional e espacialmente estratégicos no MERCOSUL.

  8. ScattAR

    Baldwin, Alex Dempster; Serafin, Stefania; Erkut, Cumhur

    2017-01-01

    We present an augmented reality (AR) audio application where scattering delay networks efficiently generate and organize a reverberator, based on room geometry scanned by an AR device. The application allows for real-time processing and updating of reflection path geometry. It provides a proof...

  9. Ramon Llull's Ars Magna

    Jensen, Thessa

    2017-01-01

    might be a viable and valuable approach to understand some of the challenges and possibilities found in computer science and ethics. Vita Llull was born in 1232 in Palma de Mallorca, a melting pot for different cul-tures and religions at the time. Being educated at the king’s court, Llull learned...... of belief, life, and God as such. Computer Science? Llull was an inspiration for later scientists, most notably Giordano Bruno, Athanasius Kirchner, Agrippa of Nettesheim and Gottfried Wilhelm Leibniz, whose dissertation De Arte Combinatoria begins with a discussion of Llull’s Ars Magna. Umberto Eco also......-ple of Mallorca have since tried to have Llull canonised as a saint. Ars Magna A few years before his death Llull began to write the most thorough and final version of his Ars Magna, the Ars Generalis Ultima [3]. The books explain the different figures of the Ars, its principles, questions, descriptions...

  10. MonitAR, Phase I

    National Aeronautics and Space Administration — We propose to develop MonitAR, an Augmented Reality (AR) system that provides procedure completion guidance to astronauts. MonitAR will replace guidance from mission...

  11. Study of the indirect calibration of clinical air kerma-area meters

    Almeida Junior, Jose N.; Terini, Ricardo A.; Herdade, Silvio B.

    2011-01-01

    Kerma-area product (P KA ) is a quantity which is independent of the distance to the X-ray tube focal spot and that can be used to assess the effective dose in patients. Clinical P KA meters are usually calibrated on-site by measuring the air kerma with an ion chamber and evaluating the irradiated area by means of a radiographic image. This work presents a preliminary metrological evaluation of the calibration of a device marketed recently (PDC, Patient Dose Calibrator, Radcal), designed for calibrating clinical P KA meters. Results are also shown of applying the PDC to the cross calibration of a clinical P KA meter from a radiology equipment. Results confirm a lower energy dependence of the PDC relative to the tested clinical meter. (author)

  12. Calibration of the indicators of the product KERMa-AREA in radiodiagnostic equipment

    Ginjaume, M.; Jarvinen, H.; Turak, O.

    2013-01-01

    Currently the IAEA proposes two procedures for the calibration of the determination of the PKA systems integrated in the x-ray equipment. The traditional method is to measure air kerma at a certain distance from the focus through an ionization chamber reference and then the area of the field of radiation in that position. The alternative method is based on measuring directly the product kerma-area using equipment calibrated in this magnitude. In both cases the calibration procedure takes into account the position of the tube on the stretcher of the patient. The objective of this study was to compare the practical application of both calibration procedures as well as assess the accuracy of indication of the PKA in the consoles of the radiology equipment. (Author)

  13. Experimental verification of the air kerma to absorbed dose conversion factor Cw,u.

    Mijnheer, B J; Wittkämper, F W; Aalbers, A H; van Dijk, E

    1987-01-01

    In a recently published code of practice for the dosimetry of high-energy photon beams, the absorbed dose to water is determined using an ionization chamber having an air kerma calibration factor and applying the air kerma to absorbed dose conversion factor Cw,u. The consistency of these Cw,u values has been determined for four commonly employed types of ionization chambers in photon beams with quality varying between 60Co gamma-rays and 25 MV X-rays. Using a graphite calorimeter, Cw,u has been determined for a graphite-walled ionization chamber (NE 2561) for the same qualities. The values of Cw,u determined with the calorimeter are within the experimental uncertainty equal to Cw,u values determined according to any of the recent dosimetry protocols.

  14. Product estimate of air kerma-area and the air kerma in the input surface of the skin of pediatric patients undergoing chest X-ray

    Villa-Chan, Beatriz; Carvalho, Aline; Andrade, Marcos Ely A.; Barros, Vinicius S.M. de; Khoury, Helen J.

    2014-01-01

    The aim of this paper is to evaluate the entrance air kerma (Ka,e) and the product air kerma-area (Pka) for chest examinations performed with pediatric patients in a large public hospital of Recife. For this study 89 examinations of patient with ages from zero to 10 years old were evaluated. The results showed that the mean Ka,e values, for patients of 0-1 years old, 1-5 years old and 5-10 years old, were, respectively, 100 mGy, 120 mGy and 100 mGy. The Pka values for newborn patients range from 11,9 to 58,4 mGy.cm 2 , for patients with 1 to 5 years old range from 17 to 192 mGy.cm 2 , and from 30,4 to 136,2 mGy.cm 2 for patients with ages from 5 to 10 years old. The differences in the Pka values are due the different dimensions of the radiation field. For the results its possible to conclude that the Pka values are high, in special for patients with ages from 1 to 5 years old, indicating that the collimation of the radiation field is not adequate. (author)

  15. Simultaneous measurement of the 37Ar and 39Ar activity

    Fisenko, A.V.

    1978-01-01

    A method for simultaneous measurement of 37 Ar and 39 Ar activities, based on the different radiation penetrabilities of these isotopes is described. Two versions are realized. In the first case, a two-section detector is used whose partition partially transmits 39 Ar β-radiation and fully absorbs 37 Ar Auger electrons. A mixture of 37 Ar and 39 Ar is introduced into an internal counter operating at anticoincidences with an external counter. In the second version, a scintillation detector is used as an external counter, while the 37 Ar- 39 Ar mixture is introduced into a gas counter with a thin cathode. The rated detection efficiency of 37 Ar radiation in both versions is 80%. When measurement duration is 500 h, the sensitivity is approximately 10 -14 and 6x10 -15 Ci for 39 Ar and 37 Ar respectively

  16. Portable meter study of ionizing radiation Teletector in high rates of air kerma

    Damatto, Willian Behling; Potiens, Maria da Penha A.; Vivolo, Vitor

    2015-01-01

    A set of portable meters of ionizing radiation high rates of air kerma (teletectors) commonly used in emergencies in Brazil and sent to the Calibration Laboratory of IPEN were under several tests and analyst is parameters for the detectors behavior were established. Applied tests were: energy dependence and primarily overload with the new irradiation system. Thus it was possible to determine the most common characteristic found in these equipment (quality control programs) and new calibration criteria were established following international recommendations. (author)

  17. Automatic dosimeter for kerma measurement based on commercial PIN photo diodes

    Kushpil, V.; Kushpil, S.; Huna, Z.

    2011-01-01

    A new automatic dosimeter for measurement of radiation dose from neutron and ionization radiation is presented. The dosimeter (kerma meter) uses commercial PIN diodes with long base as its active element. Later it provides a maximal dependence of the minority carriers life time versus absorbed dose. The characteristics of the dosimeter were measured for several types of commercial diodes. Device can be useful in many environmental or industrial applications. (authors)

  18. A comparison of measured and calculated values of air kerma rates from 137Cs in soil

    V. P. Ramzaev

    2015-01-01

    Full Text Available In 2010, a study was conducted to determine the air gamma dose rate from 137Cs deposited in soil. The gamma dose rate measurements and soil sampling were performed at 30 reference plots from the south-west districts of the Bryansk region (Russia that had been heavily contaminated as a result of the Chernobyl accident. The 137Cs inventory in the top 20 cm of soil ranged from 260 kBq m–2 to 2800 kBq m–2. Vertical distributions of 137Cs in soil cores (6 samples per a plot were determined after their sectioning into ten horizontal layers of 2 cm thickness. The vertical distributions of 137Cs in soil were employed to calculate air kerma rates, K, using two independent methods proposed by Saito and Jacob [Radiat. Prot. Dosimetry, 1995, Vol. 58, P. 29–45] and Golikov et al. [Contaminated Forests– Recent Developments in Risk Identification and Future Perspective. Kluwer Academic Publishers, 1999. – P. 333–341]. A very good coincidence between the methods was observed (Spearman’s rank coefficient of correlation = 0.952; P<0.01; on average, a difference between the kerma rates calculated with two methods did not exceed 3%. The calculated air kerma rates agreed with the measured dose rates in air very well (Spearman’s coefficient of correlation = 0.952; P<0.01. For large grassland plots (n=19, the measured dose rates were on average 6% less than the calculated kerma rates. The tested methods for calculating the air dose rate from 137Cs in soil can be recommended for practical studies in radiology and radioecology. 

  19. Sensitivity/uncertainty analysis for free-in-air tissue kerma due to initial radiation at Hiroshima and Nagasaki

    Lillie, R.A.; Broadhead, B.L.; Pace, J.V. III

    1988-01-01

    Uncertainty estimates and cross correlations by range/survivor have been calculated for the Hiroshima and Nagasaki free-in-air (FIA) tissue kerma obtained from two-dimensional air/ground transport calculations. The uncertainties due to modeling parameter and basic nuclear transport data uncertainties were calculated for 700-, 1000-, and 1500-m ground ranges. Only the FIA tissue kerma due to initial radiation was treated in the analysis; the uncertainties associated with terrain and building shielding and phantom attenuation were not considered in this study. Uncertainties of --20% were obtained for the prompt neutron and secondary gamma kerma and 30% for the prompt gamma kerma at both cities. The uncertainties on the total prompt kerma at Hiroshima and Nagasaki are --18 and 15%, respectively. The estimated uncertainties vary only slightly by ground range and are fairly highly correlated. The total prompt kerma uncertainties are dominated by the secondary gamma uncertainties, which in turn are dominated by the modeling parameter uncertainties, particularly those associated with the weapon yield and radiation sources

  20. Preparation and determination of kerma for Iridium 192 sources of low dose rate for brachytherapy

    Tendilla, J.I.; Tovar M, V.; Mitsoura, E.; Aguilar H, F.; Alanis M, J.

    2000-01-01

    The practice of Brachytherapy with Iridium-192 sources of low dose rate (0.4 - 0.8 Gy/h) is a technique used in the treatment of diverse illnesses. in this work the preparation, quality control and calibration are presented in terms of kerma in air of Iridium-192 using as target these recycled Iridium-Platinum wires. The targets were obtained as decayed sources of different radio therapeutical centers in the country and they were characterized by Scanning electron microscopy in order to determine their chemical composition. Subsequently it was developed an experimental design to establish the effect of neutron flux, geometrical array and irradiation time over the activity and percentage of the sources homogeneity. The homogeneity was determined by auto radiography and by Gamma spectroscopy. Once the optimal irradiation conditions were established, it is determined the apparent activity and kerma in air using a well type ionization chamber with traceability to a primary laboratory. Iridium-192 sources were obtained with an average homogeneity 96 %, apparent activity 282.129 ± 0.531 M Bq and kerma in air 0.03200 ± 0.00006 m Gy m/h A. (Author)

  1. Studies on effective atomic number, electron density and kerma for some fatty acids and carbohydrates

    Manohara, S R; Hanagodimath, S M; Gerward, L

    2008-01-01

    The effective atomic number, Z eff , the effective electron density, N el , and kerma have been calculated for some fatty acids and carbohydrates for photon interaction in the extended energy range from 1 keV to 100 GeV using an accurate database of photon-interaction cross sections and the WinXCom program. The significant variation of Z eff and N el is due to the variations in the dominance of different interaction processes in different energy regions. The maximum values of Z eff and N el are found in the low-energy range, where photoelectric absorption is the main interaction process. The minimum values of Z eff and N el are found at intermediate energies, typically 0.05 MeV eff is equal to the mean atomic number of the bio-molecule. Wherever possible, the calculations are compared with experimental results. A comparison is also made with the single values of the Z eff and N el provided by the program XMuDat. It is also observed that carbohydrates have a larger kerma than fatty acids in the low-energy region, where photoelectric absorption dominates. In contrast, fatty acids have a larger kerma than carbohydrates in the MeV range, where Compton scattering is the main interaction process. (note)

  2. Calculated neutron air kerma strength conversion factors for a generically encapsulated Cf-252 brachytherapy source

    Rivard, M J; D'Errico, F; Tsai, J S; Ulin, K; Engler, M J

    2002-01-01

    The sup 2 sup 5 sup 2 Cf neutron air kerma strength conversion factor (S sub K sub N /m sub C sub f) is a parameter needed to convert the radionuclide mass (mu g) provided by Oak Ridge National Laboratory into neutron air kerma strength required by modern clinical brachytherapy dosimetry formalisms indicated by Task Group No. 43 of the American Association of Physicists in Medicine (AAPM). The impact of currently used or proposed encapsulating materials for sup 2 sup 5 sup 2 Cf brachytherapy sources (Pt/Ir-10%, 316L stainless steel, nitinol, and Zircaloy-2) on S sub K sub N /m sub C sub f was calculated and results were fit to linear equations. Only for substantial encapsulation thicknesses, did S sub K sub N /m sub C sub f decrease, while the impact of source encapsulation composition is increasingly negligible as Z increases. These findings are explained on the basis of the non-relativistic kinematics governing the majority of sup 2 sup 5 sup 2 Cf neutron interactions. Neutron kerma and energy spectra resul...

  3. Avaliação da concentração de monóxido de carbono no ar exalado em tabagistas com DPOC Evaluation of the exhaled carbon monoxide levels in smokers with COPD

    Gustavo Chatkin

    2010-06-01

    Full Text Available OBJETIVO: Medir os níveis de monóxido de carbono no ar exalado (COex em tabagistas com e sem DPOC. MÉTODOS: Tabagistas frequentadores dos ambulatórios do Hospital São Lucas em Porto Alegre (RS entre setembro de 2007 e março de 2009 foram convidados a participar do estudo. Os participantes responderam a um questionário com características demográficas e epidemiológicas e realizaram espirometria, medição de cotinina urinária e de COex. Os participantes foram agrupados conforme a presença de DPOC. RESULTADOS: Foram incluídos 294 tabagistas, 174 (59,18% diagnosticados com DPOC. Todos os participantes apresentavam níveis de cotinina urinária > 50 ng/mL. Os fumantes com DPOC apresentaram medianas significativamente superiores as do grupo sem DPOC para as variáveis idade e maços-ano (p OBJECTIVE: To measure exhaled carbon monoxide (COex levels in smokers with and without COPD. METHODS: Smokers treated at outpatient clinics of São Lucas Hospital in the city of Porto Alegre, Brazil, between September of 2007 and March of 2009 were invited to participate in this study. The participants completed a questionnaire regarding demographic and epidemiologic characteristics and were submitted to spirometry, as well as to determination of COex and urinary cotinine levels. The participants were divided into two groups: those with COPD and those without COPD. RESULTS: The study involved 294 smokers, of whom 174 (59.18% had been diagnosed with COPD. All of the participants presented with urinary cotinine levels > 50 ng/mL. Smokers with COPD presented significantly higher median values for age and pack-years than did those without COPD (p < 0.001 and p = 0.026, respectively. No other statistically significant differences were found. When adjusted for gender, age at smoking onset, number of cigarettes/day and urinary cotinine level, the mean values of COex were higher, but not statistically so, in the COPD group than in the non-COPD group (17.8 ± 0

  4. Identification of excess 40Ar by the 40Ar/39Ar age spectrum technique

    Lanphere, M.A.; Dalrymple, G.B.

    1976-01-01

    40 Ar/ 39 Ar incremental heating experiments on igneous plagioclase, biotite, and pyroxene that contain known amounts of excess 40 Ar indicate that saddle-shaped age spectra are diagnostic of excess 40 Ar in igneous minerals as well as in igneous rocks. The minima in the age spectra approach but do not reach the crystallization age. Neither the age spectrum diagram nor the 40 Ar/ 36 Ar versus 39 Ar/ 36 Ar isochron diagram reliably reveal the crystallization age in such samples. (Auth.)

  5. Emprego de bomba multifásica como unidade geradora de microbolhas de ar em sistema de flotação aplicado ao pré-tratamento de efluente têxtil Multiphase pump as microbubble generator for flotation system applied to pre-treatment of textile wastewater

    Andre Pioltine

    2011-06-01

    Full Text Available O artigo apresenta os resultados de uma pesquisa desenvolvida com o objetivo de avaliar o desempenho de bomba multifásica (mistura de ar e água aplicada em substituição à câmara de saturação, em sistema de flotação localizado em uma indústria têxtil. Na unidade piloto (taxa de aplicação superficial de clarificação igual a 128,6 ± 10 m.d-1, foi verificado que os melhores resultados em termos de eficiência de remoção de turbidez e cor aparente (eficiência de remoção superior a 95% foram obtidos nos ensaios realizados com razão de recirculação em torno de 30% associada à composição volumétrica de ar de 13%.This paper presents the results of a research carried out that aims to evaluate the performance of a multiphase pump (mixture of air and water applied to replace the saturator chamber in a flotation system located in a textile industry. In the pilot unit (hydraulic surface loading equal to 128.6 ± 10 m.d-1, it was verified that the best results in terms of removal efficiency of turbidity and apparent color (efficiency removal over 95% were obtained for the essays performed with recirculation ratio equal to 30% and air supply of 13%.

  6. Determination of the reference air kerma rate for 192Ir brachytherapy sources and the related uncertainty

    Dijk, Eduard van; Kolkman-Deurloo, Inger-Karine K.; Damen, Patricia M. G.

    2004-01-01

    Different methods exist to determine the air kerma calibration factor of an ionization chamber for the spectrum of a 192 Ir high-dose-rate (HDR) or pulsed-dose-rate (PDR) source. An analysis of two methods to obtain such a calibration factor was performed: (i) the method recommended by [Goetsch et al., Med. Phys. 18, 462-467 (1991)] and (ii) the method employed by the Dutch national standards institute NMi [Petersen et al., Report S-EI-94.01 (NMi, Delft, The Netherlands, 1994)]. This analysis showed a systematic difference on the order of 1% in the determination of the strength of 192 Ir HDR and PDR sources depending on the method used for determining the air kerma calibration factor. The definitive significance of the difference between these methods can only be addressed after performing an accurate analysis of the associated uncertainties. For an NE 2561 (or equivalent) ionization chamber and an in-air jig, a typical uncertainty budget of 0.94% was found with the NMi method. The largest contribution in the type-B uncertainty is the uncertainty in the air kerma calibration factor for isotope i, N k i , as determined by the primary or secondary standards laboratories. This uncertainty is dominated by the uncertainties in the physical constants for the average mass-energy absorption coefficient ratio and the stopping power ratios. This means that it is not foreseeable that the standards laboratories can decrease the uncertainty in the air kerma calibration factors for ionization chambers in the short term. When the results of the determination of the 192 Ir reference air kerma rates in, e.g., different institutes are compared, the uncertainties in the physical constants are the same. To compare the applied techniques, the ratio of the results can be judged by leaving out the uncertainties due to these physical constants. In that case an uncertainty budget of 0.40% (coverage factor=2) should be taken into account. Due to the differences in approach between the

  7. Comparison of air-kerma strength determinations for HDR {sup 192}Ir sources

    Rasmussen, Brian E.; Davis, Stephen D.; Schmidt, Cal R.; Micka, John A.; DeWerd, Larry A. [Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)

    2011-12-15

    Purpose: To perform a comparison of the interim air-kerma strength standard for high dose rate (HDR) {sup 192}Ir brachytherapy sources maintained by University of Wisconsin Accredited Dosimetry Calibration Laboratory (UWADCL) with measurements of the various source models using modified techniques from the literature. The current interim standard was established by Goetsch et al. in 1991 and has remained unchanged to date. Methods: The improved, laser-aligned seven-distance apparatus of University of Wisconsin Medical Radiation Research Center (UWMRRC) was used to perform air-kerma strength measurements of five different HDR {sup 192}Ir source models. The results of these measurements were compared with those from well chambers traceable to the original standard. Alternative methodologies for interpolating the {sup 192}Ir air-kerma calibration coefficient from the NIST air-kerma standards at {sup 137}Cs and 250 kVp x rays (M250) were investigated and intercompared. As part of the interpolation method comparison, the Monte Carlo code EGSnrc was used to calculate updated values of A{sub wall} for the Exradin A3 chamber used for air-kerma strength measurements. The effects of air attenuation and scatter, room scatter, as well as the solution method were investigated in detail. Results: The average measurements when using the inverse N{sub K} interpolation method for the Classic Nucletron, Nucletron microSelectron, VariSource VS2000, GammaMed Plus, and Flexisource were found to be 0.47%, -0.10%, -1.13%, -0.20%, and 0.89% different than the existing standard, respectively. A further investigation of the differences observed between the sources was performed using MCNP5 Monte Carlo simulations of each source model inside a full model of an HDR 1000 Plus well chamber. Conclusions: Although the differences between the source models were found to be statistically significant, the equally weighted average difference between the seven-distance measurements and the well

  8. Comparison of air-kerma strength determinations for HDR 192Ir sources

    Rasmussen, Brian E.; Davis, Stephen D.; Schmidt, Cal R.; Micka, John A.; DeWerd, Larry A.

    2011-01-01

    Purpose: To perform a comparison of the interim air-kerma strength standard for high dose rate (HDR) 192 Ir brachytherapy sources maintained by University of Wisconsin Accredited Dosimetry Calibration Laboratory (UWADCL) with measurements of the various source models using modified techniques from the literature. The current interim standard was established by Goetsch et al. in 1991 and has remained unchanged to date. Methods: The improved, laser-aligned seven-distance apparatus of University of Wisconsin Medical Radiation Research Center (UWMRRC) was used to perform air-kerma strength measurements of five different HDR 192 Ir source models. The results of these measurements were compared with those from well chambers traceable to the original standard. Alternative methodologies for interpolating the 192 Ir air-kerma calibration coefficient from the NIST air-kerma standards at 137 Cs and 250 kVp x rays (M250) were investigated and intercompared. As part of the interpolation method comparison, the Monte Carlo code EGSnrc was used to calculate updated values of A wall for the Exradin A3 chamber used for air-kerma strength measurements. The effects of air attenuation and scatter, room scatter, as well as the solution method were investigated in detail. Results: The average measurements when using the inverse N K interpolation method for the Classic Nucletron, Nucletron microSelectron, VariSource VS2000, GammaMed Plus, and Flexisource were found to be 0.47%, -0.10%, -1.13%, -0.20%, and 0.89% different than the existing standard, respectively. A further investigation of the differences observed between the sources was performed using MCNP5 Monte Carlo simulations of each source model inside a full model of an HDR 1000 Plus well chamber. Conclusions: Although the differences between the source models were found to be statistically significant, the equally weighted average difference between the seven-distance measurements and the well chambers was 0.01%, confirming that

  9. Comparison of air-kerma strength determinations for HDR (192)Ir sources.

    Rasmussen, Brian E; Davis, Stephen D; Schmidt, Cal R; Micka, John A; Dewerd, Larry A

    2011-12-01

    To perform a comparison of the interim air-kerma strength standard for high dose rate (HDR) (192)Ir brachytherapy sources maintained by the University of Wisconsin Accredited Dosimetry Calibration Laboratory (UWADCL) with measurements of the various source models using modified techniques from the literature. The current interim standard was established by Goetsch et al. in 1991 and has remained unchanged to date. The improved, laser-aligned seven-distance apparatus of the University of Wisconsin Medical Radiation Research Center (UWMRRC) was used to perform air-kerma strength measurements of five different HDR (192)Ir source models. The results of these measurements were compared with those from well chambers traceable to the original standard. Alternative methodologies for interpolating the (192)Ir air-kerma calibration coefficient from the NIST air-kerma standards at (137)Cs and 250 kVp x rays (M250) were investigated and intercompared. As part of the interpolation method comparison, the Monte Carlo code EGSnrc was used to calculate updated values of A(wall) for the Exradin A3 chamber used for air-kerma strength measurements. The effects of air attenuation and scatter, room scatter, as well as the solution method were investigated in detail. The average measurements when using the inverse N(K) interpolation method for the Classic Nucletron, Nucletron microSelectron, VariSource VS2000, GammaMed Plus, and Flexisource were found to be 0.47%, -0.10%, -1.13%, -0.20%, and 0.89% different than the existing standard, respectively. A further investigation of the differences observed between the sources was performed using MCNP5 Monte Carlo simulations of each source model inside a full model of an HDR 1000 Plus well chamber. Although the differences between the source models were found to be statistically significant, the equally weighted average difference between the seven-distance measurements and the well chambers was 0.01%, confirming that it is not necessary to

  10. X-Rays spectrum and air kerma during a mammography study

    Ramirez G, J.; Hernandez V, R.; Chacon R, A.; Vega C, H. R.

    2009-10-01

    The X-rays spectrum produced in a mammography has been calculated by means of Monte Carlo methods. In this calculation series it is modeled the electrons source, the target and the filter. The spectra were calculated for an energy of the electrons of 28 keV and for targets of W, Mo and Rh. The calculations extended to analyze the effect that produces the filters inclusion in the spectra; the spectra of W-A1, Rh-Rh, Mo-Mo, Mo-Rh and Mo-Be were calculated this way. Using thermoluminescent dosemeters of ZrO 2 +PTFE the air kerma was measured in five points located on a phantom made with acrylic and water when it is was exposed to a X-rays beam produced by electrons of 24 keV and 10 m A of current that it produces a mammography. The values of the air kerma on the entrance surface of the phantom were compared with the calculated values by means of Monte Carlo methods. The calculated spectra present a continuous component and another discreet and its form is similar to the reported spectra in the literature. The filters inclusion allows the elimination of the low energy photons that do not have utility in the obtaining of the mammography image and only they contribute to deposit a dose in the mamma. The values of the measured air kerma indicate that the five points receive the same air kerma approximately, what means that the beam is homogeneous, of the Monte Carlo calculations we find that the center receives a bigger dose which implies that the beam is not uniform, the explanation on this fact it is attributed to that a simple model was used in the calculations, nevertheless, the average of the air kerma measured on the entrance surface of the phantom was of 0.96 ± 0.03 m G, while the obtained by means of the calculations was of 0.96 ± 0.06 mGy, when comparing both significant differences do not exist. (Author)

  11. Uso da poeira e do ar como indicadores de contaminação ambiental em áreas circunvizinhas a uma fonte de emissão estacionária de chumbo Use of dust and air as indicators of environmental pollution in areas adjacent to a source of stationary lead emission

    Simone Lorena Quiterio

    2001-06-01

    Full Text Available Neste trabalho, determinou-se o nível de chumbo (Pb presente no ar em ambientes externos e na poeira doméstica de residências localizadas próximo a uma reformadora de baterias (RB. Uma das principais fontes de exposição ao Pb são empresas do setor de RB, que ainda utilizam processos e tecnologia obsoletos em instalações precárias. Na área externa à RB foram realizadas coletas em seis pontos localizados a aproximadamente 25m e a 500m da RB. Os resultados obtidos mostram que o limite para Pb no ar atmosférico (Pb-Ar de 1,5µg Pb.m-3 foi excedido em 50% das amostras coletadas, variando de 0,03 a 183,3µg Pb.m-3. As coletas nas dependências internas e externas das residências foram realizadas em seis pontos de quatorze residências localizadas a aproximadamente 25m, 50m e a 500m da RB. O limite de Pb na poeira doméstica (Pb-Pd de 1.500µg Pb.m-2 foi excedido em 44% das amostras coletadas, apresentando valores variáveis de 2,2 a 54.338,9µg Pb.m-2.This study measured lead concentrations in both the outdoor air and household dust from houses located around a lead-acid battery repair shop. Such installations are one of the largest sources of lead exposure, since outdated technology is still used, coupled with the lack of strict air-quality control programs. Measurements of the air lead concentration around the repair shop were carried out at 6 points, approximately 25 and 500m from the shop. Over 50% of the air samples exceeded the limit of 1.5µg Pb.m-3 (range 0.03 - 183.3µg Pb.m-3. House dust samples were collected from 6 places in houses located at approximately 25, 50, and 500m from the repair shop, and the concentration of 1,500µg Pb.m-2 for lead in house dust was exceeded in 44% of the samples, with results varying from 2.2 to 54,338.9µg Pb.m-2.

  12. SU-D-209-01: Can Fluoroscopic Air-Kerma Rates Be Reliably Measured with Solid-State Meters?

    Feng, C; Thai, L; Wagner, L; Ozus, B

    2016-01-01

    Purpose: Ionization chambers remain the standard for calibration of air-kerma rate measuring devices. Despite their strong energy-dependent response, solid state radiation detectors are increasingly used, primarily due to their efficiency in making standardized measurements. To test the reliability of these devices in measuring air-kerma rates, we compared ion chambers measurements with solid-state measurements for various mobile fluoroscopes operated at different beam qualities and air-kerma rates. Methods: Six mobile fluoroscopes (GE OEC models 9800 and 9900) were used to generate test beams. Using various field sizes and dose rate controls, copper attenuators and a lead attenuator were placed at the image receptor in varying combinations to generate a range of air-kerma rates. Air-kerma rates at 30 centimeters from the image receptors were measured using two 6-cm"3 ion chambers with electrometers (Radcal, models 1015 and 9015) and two with solid state detectors (Unfors Xi and Raysafe X2). No error messages occurred during measurements. However, about two months later, one solid-state device stopped working and was replaced by the manufacturer. Two out of six mobile fluoroscopic units were retested with the replacement unit. Results: Generally, solid state and ionization chambers agreed favorably well, with two exceptions. Before replacement of the detector, the Xi meter when set in the “RF High” mode deviated from ion chamber readings by factors of 2 and 10 with no message indicating error in measurement. When set in the “RF Low” mode, readings were within −4% to +3%. The replacement Xi detector displayed messages alerting the user when settings were not compatible with air-kerma rates. Conclusion: Air-kerma rates can be measured favorably well using solid-state devices, but users must be aware of the possibility that readings can be grossly in error with no discernible indication for the deviation.

  13. SU-D-209-01: Can Fluoroscopic Air-Kerma Rates Be Reliably Measured with Solid-State Meters?

    Feng, C; Thai, L; Wagner, L [The University of Texas Health Science Center at Houston, Houston, TX (United States); Ozus, B [CHI St Luke’s Health, Baylor St Luke’s Medical Center, Houston, TX (United States)

    2016-06-15

    Purpose: Ionization chambers remain the standard for calibration of air-kerma rate measuring devices. Despite their strong energy-dependent response, solid state radiation detectors are increasingly used, primarily due to their efficiency in making standardized measurements. To test the reliability of these devices in measuring air-kerma rates, we compared ion chambers measurements with solid-state measurements for various mobile fluoroscopes operated at different beam qualities and air-kerma rates. Methods: Six mobile fluoroscopes (GE OEC models 9800 and 9900) were used to generate test beams. Using various field sizes and dose rate controls, copper attenuators and a lead attenuator were placed at the image receptor in varying combinations to generate a range of air-kerma rates. Air-kerma rates at 30 centimeters from the image receptors were measured using two 6-cm{sup 3} ion chambers with electrometers (Radcal, models 1015 and 9015) and two with solid state detectors (Unfors Xi and Raysafe X2). No error messages occurred during measurements. However, about two months later, one solid-state device stopped working and was replaced by the manufacturer. Two out of six mobile fluoroscopic units were retested with the replacement unit. Results: Generally, solid state and ionization chambers agreed favorably well, with two exceptions. Before replacement of the detector, the Xi meter when set in the “RF High” mode deviated from ion chamber readings by factors of 2 and 10 with no message indicating error in measurement. When set in the “RF Low” mode, readings were within −4% to +3%. The replacement Xi detector displayed messages alerting the user when settings were not compatible with air-kerma rates. Conclusion: Air-kerma rates can be measured favorably well using solid-state devices, but users must be aware of the possibility that readings can be grossly in error with no discernible indication for the deviation.

  14. Development of a calibration methodology and tests of kerma area product meters; Desenvolvimento de uma metodologia de calibracao e testes de medidores de produto Kerma-Area

    Costa, Nathalia Almeida

    2013-07-01

    The quantity kerma area product (PKA) is important to establish reference levels in diagnostic radiology exams. This quantity can be obtained using a PKA meter. The use of such meters is essential to evaluate the radiation dose in radiological procedures and is a good indicator to make sure that the dose limit to the patient's skin doesn't exceed. Sometimes, these meters come fixed to X radiation equipment, which makes its calibration difficult. In this work, it was developed a methodology for calibration of PKA meters. The instrument used for this purpose was the Patient Dose Calibrator (PDC). It was developed to be used as a reference to check the calibration of PKA and air kerma meters that are used for dosimetry in patients and to verify the consistency and behavior of systems of automatic exposure control. Because it is a new equipment, which, in Brazil, is not yet used as reference equipment for calibration, it was also performed the quality control of this equipment with characterization tests, the calibration and an evaluation of the energy dependence. After the tests, it was proved that the PDC can be used as a reference instrument and that the calibration must be performed in situ, so that the characteristics of each X-ray equipment, where the PKA meters are used, are considered. The calibration was then performed with portable PKA meters and in an interventional radiology equipment that has a PKA meter fixed. The results were good and it was proved the need for calibration of these meters and the importance of in situ calibration with a reference meter. (author)

  15. Proposição do índice "fração vegetada" e sua relação com alterações na temperatura do ar e no conforto térmico no período diurno e em situação de verão para Curitiba

    Flavia Cristina Osaku Minella

    Full Text Available Resumo O artigo avalia o impacto da inserção de áreas verdes na diminuição do estresse térmico do pedestre em dias com desconforto por calor. Está focado em duas importantes ações voltadas à mobilidade urbana que consideraram a inserção de vegetação como estratégia de requalificação da paisagem urbana, em Curitiba: (1 o projeto para a implantação do primeiro metrô do Estado do Paraná e (2 a transformação da antiga Rodovia Federal BR-116 em via urbana. Considerando recortes urbanos relacionados a tais projetos como áreas de estudo (Sete de Setembro e Linha Verde, o objetivo da pesquisa é propor um índice que indique a cobertura vegetal necessária para haver reduções na temperatura do ar na escala do pedestre, considerando o período diurno em situação de verão. Adicionalmente, analisa-se o impacto no conforto térmico, por meio do universal thermal climate index (UTCI. Para isso, foram utilizadas medições em campo para a coleta de dados microclimáticos, bem como simulações computacionais com a ferramenta ENVI-met. Os resultados apontam que seria necessário um aumento de cerca de 70% de cobertura vegetal para uma redução de 1°C na temperatura ambiente média da área estudada, o que indica o potencial de resfriamento de áreas vegetadas em situações urbanas.

  16. Avaliação diagnóstica da laparoscopia associada à análise do líquido intraperitoneal nas lesões intra-abdominais provocadas por arma de ar comprimido: estudo experimental em cães

    Lima, Cássio Renato Montenegro de; Steinman, Eliana; Novo, Fernando da Costa Ferreira; Heil, Romualdo Izon; Poggetti, Renato Sérgio; Birolini, Dario

    2000-01-01

    Avaliação de eficácia da laparoscopia, associada à análise bacteriológica do líquido intraperitoneal pela coloração de Gram., no diagnóstico de lesões intra-abdominais provocadas em cães com arma de ar comprimido. A alta incidência de óbitos como resultado de ferimentos por arma de fogo tem contribuído para implantação de novas técnicas diagnósticas. O uso crescente de laparoscopia diagnóstica em urgências torna necessário aprimorar qualidade e fidedignidade dos resultados obtidos. Este exper...

  17. Estimativa da produtividade de arroz irrigado em função da radiação solar global e da temperatura mínima do ar Rice yield estimates based on global solar radiation and minimum air temperature

    Silvio Steinmetz

    2013-02-01

    Full Text Available Considerando-se a importância da produção do arroz irrigado no Estado do Rio Grande do Sul e que o seu desempenho é influenciado pelas condições meteorológicas, o objetivo deste trabalho foi estimar a produtividade de grãos dessa cultura em função da radiação solar global e da temperatura mínima do ar, usando procedimentos de análise de regressão linear simples e múltipla. Realizou-se um experimento de campo, em Capão do Leão, RS, durante três anos agrícolas. Empregaram-se, em cada ano agrícola, seis datas de semeadura e oito cultivares de diferentes grupos de comprimento de ciclo. Dez colmos principais de cada cultivar foram marcados, para determinarem-se os principais estádios de desenvolvimento. A variável dependente (Y foi a média da produtividade de quatro repetições, de cada época de semeadura, e as variáveis independentes foram: a média da radiação solar global (X¹, a média da temperatura mínima do ar (X² e a média da temperatura mínima do ar elevada ao quadrado (X³, computadas em quatro períodos de desenvolvimento da planta para a radiação solar global e em três períodos para a temperatura mínima do ar. A maioria das variáveis, quando testadas isoladamente, apresentou uma relação linear significativa com a produtividade, mas os coeficientes de determinação (r² foram mais elevados nas regressões lineares múltiplas envolvendo as principais variáveis. Modelos de regressão que utilizam como variáveis preditoras a radiação solar global e a temperatura mínima do ar, em diferentes períodos de desenvolvimento da planta, mostram-se adequados para a estimativa da produtividade de grãos de arroz irrigado.Considering the importance of irrigated rice production in the State of Rio Grande do Sul and that its performance is influenced by the weather conditions, the objective of this study was to estimate the grain yield of this crop as a function of global solar radiation and minimum air

  18. Theoretical and experimental studies of the influence of air kerma rate on threshold contrast in diagnostic fluoroscopy systems

    Harrison, R M; Day, M J [Newcastle upon Tyne Univ. (UK). Newcastle General Hospital

    1983-11-01

    Experimental measurements of threshold contrast (Csub(T)) as a function of air kerma rate at the input plane of the image intensifier have been made for several diagnostic fluoroscopy units in clinical use. Threshold contrasts are determined by viewing a test object containing holes of fixed diameter and various depths under defined irradiation conditions. Kerma rate variations are effected by introducing aluminum sheets into the x-ray beam at fixed values of tube potential and current. At low kerma rates where quantum noise dominates, low tube potentials (60 kVsub(p)) usually yield lower values of Csub(T) than do higher potentials (100 kVsub(p)). At higher kerma rates the opposite is often true. A simple theoretical model for noise propagation in fluoroscopic imaging systems using models of diagnostic x-ray spectra lends qualitative support to the experimental findings. The often-quoted suggested upper limit of 100 ..mu..R s/sup -1/ (0.87 ..mu..Gy s/sup -1/) at the input phosphor would seem to be justified under the test conditions since little improvement in Csub(T) is usually observed at higher kerma rates. However, application to clinical practice would ideally require the use of more realistic phantom studies.

  19. Ramon Llull's Ars Magna

    Jensen, Thessa

    2018-01-01

    The Ars Magna of Ramon Llull must be seen as one of the first attempts to formalise language, thought processes, and creating a basis for rational discussions. It consists of so-called principles, concepts, which are defined and combined through the use of four main figures. Llull's contribution...

  20. 40Ar/39Ar studies of deep sea igneous rocks

    Seidemann, D.

    1978-01-01

    An attempt to date deep-sea igneous rocks reliably was made using the 40 Ar/ 39 Ar dating technique. It was determined that the 40 Ar/ 39 Ar incremental release technique could not be used to eliminate the effects of excess radiogenic 40 Ar in deep-sea basalts. Excess 40 Ar is released throughout the extraction temperature range and cannot be distinguished from 40 Ar generated by in situ 40 K decay. The problem of the reduction of K-Ar dates associated with sea water alteration of deep-sea igneous rocks could not be resolved using the 40 Ar/ 39 Ar technique. Irradiation induced 39 Ar loss and/or redistribution in fine-grained and altered igneous rocks results in age spectra that are artifacts of the experimental procedure and only partly reflect the geologic history of the sample. Therefore, caution must be used in attributing significance to age spectra of fine grained and altered deep-sea igneous rocks. Effects of 39 Ar recoil are not important for either medium-grained (or coarser) deep-sea rocks or glasses because only a small fraction of the 39 Ar recoils to channels of easy diffusion, such as intergranular boundaries or cracks, during the irradiation. (author)

  1. Product kerma in the air-area and radiation dose in dental radiodiagnosis

    Costa, Alessandro Martins da

    2014-01-01

    The main purpose of patient dosimetry in diagnostic radiology is to determine dosimetric quantities for the establishment and use of reference levels and comparative risk assessment. In recent publications the use of the air kerma-area product, PKA, has been suggested in dental radiology, as this quantity is more closely related to risk. The aim of this study was to perform a preliminary survey of PKA and effective dose in different types of dental examinations. The future perspective is a large-scale survey for the establishment and use of diagnostic reference levels in dentistry in Brazil. (author)

  2. Reference natural radionuclide concentrations in Australian soils and derived terrestrial air kerma rate.

    Kleinschmidt, R

    2017-06-01

    Sediment from drainage catchment outlets has been shown to be a useful means of sampling large land masses for soil composition. Naturally occurring radioactive material concentrations (uranium, thorium and potassium-40) in soil have been collated and converted to activity concentrations using data collected from the National Geochemistry Survey of Australia. Average terrestrial air kerma rate data are derived using the elemental concentration data, and is tabulated for Australia and states for use as baseline reference information. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  3. Image quality and volume computed tomography air kerma index (Cvol) evaluation in Recife

    Andrade, Marcos Ely Almeida

    2008-01-01

    The Computed Tomography (CT) is an important diagnostic imaging method, widely used. However, in spite of all the advantages and technologic advances within the CT scanners, the tomographic procedures result in high absorbed doses to patients. The main objective of this work was to perform a dosimetric study of CT scanners located at Recife and to evaluate the image quality on CT examinations in these equipment. The volume CT air kerma index (C VOL ) and air kerma length product (P KL,CT ) were estimated. These values were calculated using normalized weighted air kerma indexes in CT standard dosimetry phantoms ( n C W ), supplied by ImPACT group for several CT scanners, and the scan parameters of routine head, routine chest and hi-resolution chest CT exams performed at 20 institutions. The irradiation parameters of 15 adult patients for each CT procedure were registered at six participating centres, at which the phantom from the American College of Radiology (ACR) CT accreditation protocol was used for the image quality measurements. For routine head exams, the C VOL values varied between 12 and 58 mGy (at the posterior fossa) and 15 to 58 mGy (at the cerebrum) and the P KL,CT , from 150 to 750 mGy·cm. The C VOL values for routine chest procedures varied from 3 to 26 mGy and the P KL,CT , between 120 and 460 mGy·cm. In relation to Hi-resolution chest exams, C VOL values were from 1.0 to 2.7 mGy and the P KL,CT values varied between 24 and 67 mGy·cm. The image quality evaluations results showed that almost all scanners presented at least one inadequacy. One of the equipment presented faults at 70% of the tests. With regard to the image noise, only two scanners presented acceptable results. From these results, it is possible to conclude that the volume CT air kerma index values are lower than the European reference levels. However, the image quality of these CT scanners does not attend the ACR requirements, suggesting the need to implement quality assurance

  4. Application of the total etching technique or self-etching primers on primary teeth after air abrasion Aplicação da técnica de condicionamento total ou de "primers" autocondicionantes em dentes decíduos após abrasão a ar

    Fábio Renato Manzolli Leite

    2005-09-01

    Full Text Available Since the use of air abrasion has grown in pediatric dentistry, the aim of this study was to evaluate, by means of shear bond strength testing, the need to use the total etching technique or self-etching primers on dentin of primary teeth after air abrasion. Twenty-five exfoliated primary molars had their occlusal dentin exposed by trimming and polishing. Specimens were treated by: Air abrasion + Scotchbond MultiPurpose adhesive (G1; 37% phosphoric acid + Scotchbond MP adhesive (G2; Clearfil SE (G3; Air abrasion + 37% phosphoric acid + Scotchbond MP adhesive (G4; Air abrasion + Clearfil SE (G5. On the treated surface, a cylinder of 2 mm by 6 mm was made using a composite resin (Z100. Duncan's test showed that: (G2 = G3 = G5 > (G1 = G4. The use of a self-etching primer on air abraded dentin is recommended to obtain higher bond strengths.Como o uso da abrasão a ar tem aumentado em odontopediatria, o objetivo deste trabalho foi avaliar a resistência ao cisalhamento da resina composta Z100 sobre a superfície dentinária de dentes decíduos após abrasionamento a ar associado ou não a técnica de condicionamento total (ácido fosfórico + Scotchbond Multi Purpose ou "primer" autocondicionante (Clearfil SE Bond. A superfície oclusal de 25 molares decíduos foi removida para exposição completa da superfície dentinária. Após polimento com lixas abrasivas, foram divididos em 5 grupos (5 espécimes em cada tratados por abrasão + adesivo Scotchbond (G1; condicionamento ácido + adesivo Scotchbond (G2; adesivo Clearfil (G3; abrasão a ar + condicionamento ácido + adesivo Scotchbond (G4; abrasão a ar + adesivo Clearfil (G5. Uma matriz bipartida foi adaptada à superfície dentinária e preenchida com resina composta. Após polimerização, corpos-de-prova de 2 mm x 6 mm foram obtidos. O teste de Duncan mostrou a desigualdade (G1 = G4 < (G2 = G3 = G5. Desse modo, conclui-se que, após o abrasionamento dentinário, deve ser utilizado o sistema de

  5. BACTERIAL DETERIORANTS IN CHICKEN BREAST FILLET PACKAGED IN AIR, VACUUM AND IRRADIATED: BACTERIOLOGICAL GROWTH PARAMETERS AND SHELF-LIFE BACTÉRIAS DETERIORANTES EM FILÉS DE FRANGO EMBALADOS EM AR, VÁCUO E IRRADIADOS: PARÂMETROS BACTERIOLÓGICOS DE DESENVOLVIMENTO E PRAZO COMERCIAL

    Samira Pirola Santos Mantilla

    2009-10-01

    Full Text Available

    The objective of this research was to evaluate the effect of packaging in 100% air and vacuum, combined with radiation (2 kGy and 3 kGy, on chicken breast fillet shelf-life by evaluation of bacterial deteriorants growth and pH variation parameters. The vacuum packaging increased shelf-life, when compared to commercial packaging in 100% air, both in non-irradiated and irradiated to 3 kGy fillets. The irradiation increased the shelf-life of fillet samples at both doses. The lactic acid bacteria were the organisms that most developed in irradiated samples, showing greater radioresistance, as compared to other microorganisms studied, while the enterobacteria showed greater sensitivity to treatment with ionizing radiation. The vacuum packaging, combined with irradiation, can be used to improve the safety of chicken breast fillets and to extend its shelf-life.

    KEY-WORDS: Deterioration; chicken meat; vacuum packaging; meat radiation.

    O objetivo deste experimento foi avaliar o efeito do uso de embalagens, em 100% ar e a vácuo, combinadas com a radiação gama (2 kGy e 3 kGy, no aumento do prazo de validade comercial de filé de peito de

  6. MO-D-213-07: RadShield: Semi- Automated Calculation of Air Kerma Rate and Barrier Thickness

    DeLorenzo, M; Wu, D; Rutel, I; Yang, K

    2015-01-01

    Purpose: To develop the first Java-based semi-automated calculation program intended to aid professional radiation shielding design. Air-kerma rate and barrier thickness calculations are performed by implementing NCRP Report 147 formalism into a Graphical User Interface (GUI). The ultimate aim of this newly created software package is to reduce errors and improve radiographic and fluoroscopic room designs over manual approaches. Methods: Floor plans are first imported as images into the RadShield software program. These plans serve as templates for drawing barriers, occupied regions and x-ray tube locations. We have implemented sub-GUIs that allow the specification in regions and equipment for occupancy factors, design goals, number of patients, primary beam directions, source-to-patient distances and workload distributions. Once the user enters the above parameters, the program automatically calculates air-kerma rate at sampled points beyond all barriers. For each sample point, a corresponding minimum barrier thickness is calculated to meet the design goal. RadShield allows control over preshielding, sample point location and material types. Results: A functional GUI package was developed and tested. Examination of sample walls and source distributions yields a maximum percent difference of less than 0.1% between hand-calculated air-kerma rates and RadShield. Conclusion: The initial results demonstrated that RadShield calculates air-kerma rates and required barrier thicknesses with reliable accuracy and can be used to make radiation shielding design more efficient and accurate. This newly developed approach differs from conventional calculation methods in that it finds air-kerma rates and thickness requirements for many points outside the barriers, stores the information and selects the largest value needed to comply with NCRP Report 147 design goals. Floor plans, parameters, designs and reports can be saved and accessed later for modification and recalculation

  7. MO-D-213-07: RadShield: Semi- Automated Calculation of Air Kerma Rate and Barrier Thickness

    DeLorenzo, M [Oklahoma University Health Sciences Center, Oklahoma City, OK (United States); Wu, D [University of Oklahoma Health Sciences Center, Oklahoma City, Ok (United States); Rutel, I [University of Oklahoma Health Science Center, Oklahoma City, OK (United States); Yang, K [Massachusetts General Hospital, Boston, MA (United States)

    2015-06-15

    Purpose: To develop the first Java-based semi-automated calculation program intended to aid professional radiation shielding design. Air-kerma rate and barrier thickness calculations are performed by implementing NCRP Report 147 formalism into a Graphical User Interface (GUI). The ultimate aim of this newly created software package is to reduce errors and improve radiographic and fluoroscopic room designs over manual approaches. Methods: Floor plans are first imported as images into the RadShield software program. These plans serve as templates for drawing barriers, occupied regions and x-ray tube locations. We have implemented sub-GUIs that allow the specification in regions and equipment for occupancy factors, design goals, number of patients, primary beam directions, source-to-patient distances and workload distributions. Once the user enters the above parameters, the program automatically calculates air-kerma rate at sampled points beyond all barriers. For each sample point, a corresponding minimum barrier thickness is calculated to meet the design goal. RadShield allows control over preshielding, sample point location and material types. Results: A functional GUI package was developed and tested. Examination of sample walls and source distributions yields a maximum percent difference of less than 0.1% between hand-calculated air-kerma rates and RadShield. Conclusion: The initial results demonstrated that RadShield calculates air-kerma rates and required barrier thicknesses with reliable accuracy and can be used to make radiation shielding design more efficient and accurate. This newly developed approach differs from conventional calculation methods in that it finds air-kerma rates and thickness requirements for many points outside the barriers, stores the information and selects the largest value needed to comply with NCRP Report 147 design goals. Floor plans, parameters, designs and reports can be saved and accessed later for modification and recalculation

  8. Avaliação da composição química de milho seco e armazenado em silo tipo alambrado com ar natural forçado Evaluation of chemical composition of corn dried and stored with forced natural air

    Luiz Carlos Gutkoski

    2009-12-01

    Full Text Available O trabalho objetivou estudar o efeito da umidade de colheita e do tempo de armazenamento em grãos de milho secos e armazenados em silos com ar natural forçado. Grãos de milho colhidos com 17,8; 18,9 e 20,5% de água foram acondicionados em silos tipo alambrado com fundo falso perfurado e com ventiladores ligados ininterruptamente até a secagem. Amostras de milho foram coletadas nos tempos zero, 4, 8, 22 e 112 dias, em seis alturas de camada de cada silo (10, 60, 110, 160, 210 e 260 cm. A composição química foi determinada pelo uso de Espectrofotômetro do Infravermelho Proximal (NIR e os resultados expressos em porcentagem e em base seca. Os dados foram analisados estatisticamente (Anova e nas interações significativas, elaborados os gráficos de regressão. Nas determinações de proteínas, lipídios, matéria seca e fibra em detergente neutro as interações foram significativas ao nível de 5% de probabilidade de erro, enquanto que em cinzas, umidade e carboidratos não foram verificadas diferenças significativas. A aeração natural forçada é capaz de reduzir a umidade do milho para 13%, sendo tecnicamente viável em propriedades familiares.The aim of this work was to study the effects of moisture at harvest and time of storage upon grains of corn dried and stored in bins with forced natural air. Grains of corn harvested with 17.8; 18.9, and 20.5% of water were stored in drying bins with false floor with fans working full-time until drying. Samples of corn were collected at zero, 4, 8, 22, and 112 days from six different heights in each bin (10, 60, 110, 160, 210 and 260 cm. The chemical composition was determined through Near-Infrared Spectrophotometer (NIR and the results were expressed in percentage at dry basis. The data were statistically analyzed (Anova and for the significant interactions graphics of regression were provided. In the process of determination of protein, fat, dry matter, and neutral detergent fiber the

  9. Influences of atom Ar on Ar at C60 + Ar at C60 collisions

    Zhao Qiang; Zhou Hongyu; Zhang Fengshou

    2007-01-01

    A semi-emperical molecular dynamics model was developed. The central collisions of C 60 + C 60 and Ar at C 60 + Ar at C 60 at the same incident energy were investigated within this model. The fullerene dimers could be formed by a self-assembly of C 60 fullerene, and the new fullerene structure like 'peanut' could be formed by a self-assembly of Ar at C 60 . It was found that atom Ar had a great effect on the collision of Ar at C 60 + Ar at C 60 . (authors)

  10. Ars Electronica tulekul / Rael Artel

    Artel, Rael, 1980-

    2003-01-01

    6.-11. IX toimub Austrias Linzis "Ars Electronica" festival, mille teema on "Code - The Language of Our Time". Festivali kavast, osalejatest, ava-performance'ist "Europe - A Symphonic Vision", näitusest "Cyberarts 2003. Prix Ars Electronica"

  11. Kerma rate evaluation in the air in a room interventional cardiology

    Real, Jessica V.; Luz, Renata M. da; Fröhlich, Bruna D.; Silva, Ana Maria Marques da

    2014-01-01

    In recent years, the number of interventional cardiology procedures is increasing. However, due to the long time of fluoroscopy in these procedures, care teams can receive high doses of radiation. The radiation scattered by the patient is not uniform, and their assessment is of utmost importance. This study aimed to estimate and map the kerma rate in the air at the time of the gonads, in an interventional cardiology room, seeking to optimize the dose absorbed by individuals occupationally exposed to ionizing radiation. For data collection, the room was divided into quadrants of 1m 2 , totaling 40 collection points. The simulator was positioned so that its entry surface was located in the interventional reference point. Were chosen the conditions that simulate angiography and angioplasty procedures performed in the service. The data were obtained for height of 1 meter, gonad region. The results obtained for kerma rates in air, in quadrants, show that higher measured values was in the vicinity of the X-ray tube. Has been found that the medical staff are more exposed, because of its location during the procedure, around the table. The law of the inverse square distance of the farthest points of the X-ray tube were verified

  12. A new approach to the determination of air kerma using primary-standard cavity ionization chambers

    Burns, D T

    2006-01-01

    A consistent formalism is presented using Monte Carlo calculations to determine the reference air kerma from the measured energy deposition in a primary-standard cavity ionization chamber. A global approach avoiding the use of cavity ionization theory is discussed and its limitations shown in relation to the use of the recommended value for W. The role of charged-particle equilibrium is outlined and the consequent requirements placed on the calculations are detailed. Values for correction factors are presented for the BIPM air-kerma standard for 60 Co, making use of the Monte Carlo code PENELOPE, a detailed geometrical model of the BIPM 60 Co source and event-by-event electron transport. While the wall correction factor k wall = 1.0012(2) is somewhat lower than the existing value, the axial non-uniformity correction k an = 1.0027(3) is significantly higher. The use of a point source in the evaluation of k an is discussed. A comparison is made of the calculated dose ratio with the Bragg-Gray and Spencer-Attix stopping-power ratios, the results indicating a preference for the Bragg-Gray approach in this particular case. A change to the recommended value for W of up to 2 parts in 10 3 is discussed. The uncertainties arising from the geometrical models, the use of phase-space files, the radiation transport algorithms and the underlying radiation interaction coefficients are estimated

  13. Determination of the conversion coefficient for ambient dose equivalent, H(10), from air kerma measurements

    Gonzalez J, F.; Alvarez R, J. T.

    2015-09-01

    Namely the operational magnitudes can be determined by the product of a conversion coefficient by exposure air kerma or fluence, etc. In particular in Mexico for the first time is determined the conversion coefficient (Cc) for operational magnitude Environmental Dose Equivalent H(10) by thermoluminescence dosimetry (TLD) technique. First 30 TLD-100 dosimeters are calibrated in terms of air kerma, then these dosimeters are irradiated inside a sphere ICRU type of PMMA and with the aid of theory cavity the absorbed dose in PMMA is determined at a depth of 10 mm within the sphere D PMMA (10), subsequently absorbed dose to ICRU tissue is corrected and the dose equivalent H(10) is determined. The Cc is determined as the ratio of H(10)/K a obtaining a value of 1.20 Sv Gy -1 with a u c = 3.66%, this being consistent with the published value in ISO-4037-3 of 1.20 Sv Gy -1 with a u c = 2%. (Author)

  14. Measurement of air kerma rate for Cs-137 using different ionization chambers

    Mohammed, K. T. A.

    2013-07-01

    Due to the importance of radiation doses in medical field quality assurance should be established in order to maintain a reasonable balance between the purpose of application and exposure. This study had been carried out to achieve quality control for protection based on air kerma rate. Measurements were performed by using Cs-137 for the comparison of two working ionization chambers in secondary standard dosimetry laboratory of Sudan. Spherical ionization chamber L S-01 1000 cc S/N 912 and Farmer ionization chamber 2675 A 600 cc S/N 0511, respectively. The results obtained from this study have been represented as mean and their standard deviations shown in most cases remains at 5% uncertainly. Comparison between kinetic energy released per unit mass in air rate (air kerma rate) were obtained by using spherical ionization chamber L S-01 1000 cc S/N 912 and results have been determined using inverse square law. The differences have been represented as means and standard deviations with significant P-value less than 0.05. Spherical ionization chamber gives accurate, reproducible results with acceptable uncertainty which is more suitable for calibration of radiation detectors.(Author)

  15. Air-kerma evaluation at the maze entrance of HDR brachytherapy facilities

    Pujades, M C; Granero, D; Vijande, J; Ballester, F; Perez-Calatayud, J; Papagiannis, P; Siebert, F A

    2014-01-01

    In the absence of procedures for evaluating the design of brachytherapy (BT) facilities for radiation protection purposes, the methodology used for external beam radiotherapy facilities is often adapted. The purpose of this study is to adapt the NCRP 151 methodology for estimating the air-kerma rate at the door in BT facilities. Such methodology was checked against Monte Carlo (MC) techniques using the code Geant4. Five different facility designs were studied for 192 Ir and 60 Co HDR applications to account for several different bunker layouts. For the estimation of the lead thickness needed at the door, the use of transmission data for the real spectra at the door instead of the ones emitted by 192 Ir and 60 Co will reduce the lead thickness by a factor of five for 192 Ir and ten for 60 Co. This will significantly lighten the door and hence simplify construction and operating requirements for all bunkers. The adaptation proposed in this study to estimate the air-kerma rate at the door depends on the complexity of the maze: it provides good results for bunkers with a maze (i.e. similar to those used for linacs for which the NCRP 151 methodology was developed) but fails for less conventional designs. For those facilities, a specific Monte Carlo study is in order for reasons of safety and cost-effectiveness. (paper)

  16. Air-kerma evaluation at the maze entrance of HDR brachytherapy facilities.

    Pujades, M C; Granero, D; Vijande, J; Ballester, F; Perez-Calatayud, J; Papagiannis, P; Siebert, F A

    2014-12-01

    In the absence of procedures for evaluating the design of brachytherapy (BT) facilities for radiation protection purposes, the methodology used for external beam radiotherapy facilities is often adapted. The purpose of this study is to adapt the NCRP 151 methodology for estimating the air-kerma rate at the door in BT facilities. Such methodology was checked against Monte Carlo (MC) techniques using the code Geant4. Five different facility designs were studied for (192)Ir and (60)Co HDR applications to account for several different bunker layouts.For the estimation of the lead thickness needed at the door, the use of transmission data for the real spectra at the door instead of the ones emitted by (192)Ir and (60)Co will reduce the lead thickness by a factor of five for (192)Ir and ten for (60)Co. This will significantly lighten the door and hence simplify construction and operating requirements for all bunkers.The adaptation proposed in this study to estimate the air-kerma rate at the door depends on the complexity of the maze: it provides good results for bunkers with a maze (i.e. similar to those used for linacs for which the NCRP 151 methodology was developed) but fails for less conventional designs. For those facilities, a specific Monte Carlo study is in order for reasons of safety and cost-effectiveness.

  17. Kerma factors for neutrons of 14 MeV to 60 MeV in elemental H, C, N and O

    Behrooz, M.A.; Watt, D.E. (Dundee Univ. (UK). Dept. of Medical Biophysics)

    1981-01-01

    Total kerma factors, and partial kerma factors for production of specified charged H and He particles and heavier recoils, have been computed using basic theoretical and experimental nuclear data for neutrons at energies between 14 MeV and 60 MeV in the main tissue elements and in ICRU muscle tissue. All the more recent computations of total kerma factors, along with those determined from direct experimental measurements of partial kerma factors, now form a reasonably consistent set of data enabling average total kerma factors with coefficients of better than 3% for hydrogen, 16% for carbon, 23% for nitrogen and 9% for oxygen to be recommended for application to medical dosimetry and radiation protection. Total kerma factors for ICRU muscle tissue have a precision of better than 2.5% over the neutron energy range considered. Although there is adequate precision for total kerma factors for soft tissue, nevertheless analysis of the partial kerma factors indicates that caution must be exercised in use of the information for quality specification, e.g. in microdose spectra, and that more detailed basic reaction data is required for fast neutrons.

  18. Air-over-ground calculations of the neutron, prompt, and secondary-gamma free-in-air tissue kerma from the Hiroshima and Nagasaki devices

    Pace, J.V. III; Knight, J.R.; Bartine, D.E.

    1982-01-01

    This paper reports preliminary results of the two-dimensional discrete-ordinate, calculations for the air-over-ground transport of radiation from the Hiroshima and Nagasaki weapon devices. It was found that the gamma-ray kerma dominated the total kerma for both environments

  19. ARABIC LIGHT STEMMER (ARS

    ASMA AL-OMARI

    2014-12-01

    Full Text Available Stemming is a main step used to process textual data. It is usually used in several types of applications such as: text mining, information retrieval (IR, and natural language processing (NLP. A major task in stemming is to standardize words; which can be achieved by reducing each word to its base (root or stem. Arabic stemming is not an easy task. Unlike other languages, Arabic language is a highly inflected language, since it uses many inflectional forms. Researchers are divided on the benefit of using stemming in fields of IR, NLP...etc., since in Arabic the morphological variants of a certain word are not always semantically related. The aim of this paper is to design and implement a new Arabic light stemmer (ARS which is not based on Arabic root patterns. Instead, it depends on well defined mathematical rules and several relations between letters. A series of tests were conducted on ARS stemmer to compare its effectiveness with the effectiveness of two other Arabic stemmers. Test shows clearly the effectiveness superiority of ARS compared to effectiveness of these two Arabic stemmers.

  20. Temperature and pressure effects on 40Ar-39Ar systematics

    Ozima, M.; Kaneoka, I.; Yanagisawa, M.

    1979-01-01

    The effects of thermal and compressional treatment on 40 Ar- 39 Ar systematics have been investigated on three artificially heated biotite samples (heated for 1 hour at 700 0 C and 860 0 C in air and 700 0 C in vacuum respectively) and uniaxially compressed granite (p=1400 bar) and basalt samples (p=1660 bar). The 40 Ar- 39 Ar results for the disturbed samples are compared with those for undisturbed samples. Except for the vacuum-heating case, the effects of the disturbances may be interpreted as the combined effect of a partial loss of radiogenic 40 Ar from the sample and an incorporation of air Ar into the sample. Common diagnostic effects are (1) reduction of the total fusion age, (2) distortion of the age spectrum and, if the degree of the partial Ar loss is small (3) approximate preservation of the isochron age, and (4) reduction of the intercept value ( 40 Ar/ 36 Ar) in the isochron plot. The features observed in the age spectra of artificially disturbed samples are rather common in geologically disturbed samples, suggesting that the artificial disturbances simulate the effects of geological disturbances on 40 Ar- 39 Ar systematics. (Auth.)

  1. Spectroanalytical investigations on inductively coupled N2/Ar and Ar/Ar high frequency plasmas

    Malinowski, P.; Mazurkiewicz, M.; Nickel, H.

    1981-03-01

    In order to improve the detection limits of trace elements in corrosion products of metallic materials, the inductively coupled plasma excitation source (ICP) was applied for spectroscopic analysis. Besides optimizing the working conditions for the mentioned materials, the fundamental research clearing the excitation processes in ICP was carried out. Basicly, two plasma systems were investigated: the nitrogen cooled N 2 /Ar- and pure Ar/Ar-plasma. The computed detection limits for 8 chosen elements are between 0.1 and 50 μg ml -1 in both plasmas. The advantage of ion lines was clearly present; in N 2 /Ar-plasma it was larger than in Ar/Ar-plasma. The excitation temperatures measured with help of ArI, FeI and ZnI lines rise with increasing power and decreasing distance from the induction coil. The distribution of Zn excitation temperature in N 2 /Ar-plasma as well as the measured N + 2 rotational and CN vibrational temperatures indicate, that the toroidal structure of Ar/Ar-plasma is not analogue to the N 2 /Ar-plasma. The values of the various excitation temperatures (Ar, Fe, Zn) and the differences between the excitation, vibration, rotation and ionization temperatures (Tsub(i) > Tsub(n) = Tsub(vib) > Tsub(rot)) indicate an absence of thermal equilibrium in the concerned system. (orig.)

  2. Importance of the neutrons kerma coefficient in the planning of Brachytherapy treatments with Cf-252 sources

    Paredes G, L.; Balcazar G, M.; Azorin N, J.; Francois L, J.L.

    2006-01-01

    The Cf-252 is a fast neutrons emitting radioisotope by spontaneous fission that can be used as sealed source in medicine applications, industry and research. Commercially its offer sources of different sizes, compact and with a fast neutrons emission of the order of 10 6 n/s-μg and an energy spectra that presents respectively maxim and average energy in 2.1 MeV and 0.7 MeV. In medicine new applications are being developed for the treatment of patient with hypoxic and voluminous tumors, where the therapy with photons has not given positive results, as well as for the protocols of therapy treatment by boron neutron capture, where very small sources of Cf-252 will be used with the interstitial brachytherapy technique of high and low dose rate. In this work an analysis of how the small differences that exist in the elementary composition of 4 wicked tumors, 4 ICRU healthy tissues and 3 substitute materials of ICRU tissue used in dosimetry are presented, its generate changes in the neutrons kerma coefficient in function of the energy and consequently in the absorbed dose in the interval of 11 eV to 29 MeV. These differences can produce maximum variations of the neutron kerma coefficients ratio for E n > 1 keV of the one: 15% tumor/ICRU guest healthy tissue, 12% ICRU tumor/muscle, 12% ICRU healthy tissues ICRU/ICRU muscle, 22% substitutes tissue/tumor and 22% ICRU substitutes tissue/muscle. Also, it was found that the average value of the neutrons kerma coefficient for the 4 wicked tumors is from 6% to 7% smaller that the average value for the soft tissue in the interval energy of interest for therapy with fast neutrons with E n > 1 MeV. These results have a special importance during the planning process of brachytherapy treatments with sources of 252 Cf, to optimize and to individualize the patients treatments. (Author)

  3. Total reference air kerma can accurately predict isodose surface volumes in cervix cancer brachytherapy. A multicenter study

    Nkiwane, Karen S; Andersen, Else; Champoudry, Jerome

    2017-01-01

    PURPOSE: To demonstrate that V60 Gy, V75 Gy, and V85 Gy isodose surface volumes can be accurately estimated from total reference air kerma (TRAK) in cervix cancer MRI-guided brachytherapy (BT). METHODS AND MATERIALS: 60 Gy, 75 Gy, and 85 Gy isodose surface volumes levels were obtained from treatm...

  4. Tissue kerma vs distance relationships for initial nuclear radiation from the atomic devices detonated over Hiroshima and Nagasaki

    Kerr, G.D.; Pace, J.V. III; Scott, W.H. Jr.

    1983-06-01

    Initial nuclear radiation is comprised of prompt neutrons and prompt primary gammas from an exploding nuclear device, prompt secondary gammas produced by neutron interactions in the environment, and delayed neutrons and delayed fission-product gammas from the fireball formed after the nuclear device explodes. These various components must all be considered in establishing tissue kerma vs distance relationships which describe the decrease of initial nuclear radiation with distance in Hiroshima and in Nagasaki. The tissue kerma at ground evel from delayed fission-product gammas and delayed neutrons was investigated using the NUIDEA code developed by Science Applications, Inc. This code incorporates very detailed models which can take into account such features as the rise of the fireball, the rapid radioactive decay of fission products in it, and the perturbation of the atmosphere by the explosion. Tissue kerma vs distance relationships obtained by summing results of these current state-of-the-art calculations will be discussed. Our results clearly show that the prompt secondary gammas and delayed fission-product gammas are the dominant components of total tissue kerma from initial nuclear radiation in the cases of the atomic (or pure-fission) devices detonated over Hiroshima and Nagasaki

  5. Revisão sistemática sobre a epidemiologia das doenças cardiovasculares e respiratórias e suas associações com a poluição do ar em Vitória/ES

    Sergio Tufik

    2017-07-01

    Full Text Available Introdução: A poluição do ar é um importante fator ambiental relacionado a doenças crônicas não transmissíveis, como doenças cardiovasculares e respiratórias. Essa relação torna-se importante em cidades com alta atividade industrial, como Vitória/ES. Esta pesquisa utilizou três revisões sistemáticas (RSs distintas para avaliar a epidemiologia das doenças cardiovasculares (RS1, a epidemiologia das doenças respiratórias (RS2 e a associação entre poluição do ar e doenças cardiorrespiratórias (RS3 na cidade de Vitória. Métodos: A busca bibliográfica considerou três bases de dados (PubMed, Scopus e LILACS. Foi estabelecida uma quantidade mínima de três estudos para a condução de metanálises. A heterogeneidade de cada análise foi calculada pelo índice I2 . Resultados: A busca bibliográfica resultou em 1.205 registros, dos quais 27 foram incluídos – 17 na RS1, cinco na RS2 e cinco na RS3. Apenas dois desfechos puderam ser avaliados por meio de metanálises: prevalência de hipertensão e prevalência de asma em crianças. Estima-se uma prevalência de 34% (IC95%: 24-45 de hipertensão e de 12% (IC95%: 1-32 de asma em crianças. Os poluentes mais avaliados foram MP10 e SO2 , para os quais não se pôde realizar metanálises. Todas as análises apresentaram baixo número de registros incluídos e alta heterogeneidade. Conclusão: Há poucos dados disponíveis sobre a associação de doenças cardiorrespiratórias e poluição ambiental em Vitória. A heterogeneidade, a diversidade de desfechos e a baixa quantidade de estudos impediram a condução de análises mais profundas e limitaram o poder de síntese e conclusão dessas revisões, impossibilitando uma avaliação adequada dos objetivos propostos. São necessários mais estudos epidemiológicos com amostras de grande porte e representativas para que se tenha resultados conclusivos sobre a relação entre poluição ambiental e doenças cardiorrespirat

  6. 40Ar/39Ar age calibration against counted annuallayers

    Storey, Michael; Stecher, Ole

    2008-01-01

    The 40Ar/39Ar method, based on the decay of the naturally occurring radioactive isotope 40K, is capable of producing ages with precision better than ± 0.1 %. However, accuracy is limited to no better than 1 % mainly due to the relatively large uncertainty in the 40K decay constants. One approach...... worth exploring for an improved absolute age basis for the 40Ar/39Ar system is through cross-calibration with counted annual layers (e.g. tree rings, varves and ice cores). North Atlantic Ash Zone (NAAZ) II is found within the dated part of the annual Greenland ice core record. NAAZ II has been...... correlated to the Icelandic peralkaline rhyolitic Thorsmörk ignimbrite. We will present preliminary 40Ar/39Ar results on the age of this eruption...

  7. Velocidade do ar em barra de pulverização na deposição da calda fungicida, severidade da ferrugem asiática e produtividade da soja Effect of the air speed in sleeve boom on pesticide spray deposition, severity and soybean crop yield

    Evandro Pereira Prado

    2010-03-01

    Full Text Available O trabalho objetivou comparar a deposição da pulverização e o controle da ferrugem asiática após o tratamento com fungicidas sob quatro velocidades da assistência de ar junto à barra de pulverização na cultura da soja. Dois experimentos foram conduzidos na FCA/UNESP - Campus de Botucatu, safra 2006/07. Alvos artificiais foram fixados na superfície adaxial e abaxial de folíolos posicionados nas partes superior e inferior das plantas selecionadas e distribuídas perpendicularmente ao deslocamento do pulverizador. O oxicloreto de cobre (50% de cobre metálico foi o marcador utilizado em pulverização e a determinação quantitativa dos depósitos feita com o uso de espectrofotometria de absorção atômica. Após a aplicação do fungicida piraclostrobina + epoxiconazole sob diferentes velocidades da assistência de ar junto à barra de pulverização (0, 9, 11 e 29 km h-1 procedeu-se a avaliação da severidade da doença e produtividade da soja. Na parte superior das plantas os maiores níveis de depósitos foram encontrados na pulverização sem assistência de ar. Já na parte inferior da planta foram encontrados os maiores níveis de deposição quando foram utilizadas as maiores velocidades da assistência de ar. No geral, a severidade da doença foi mais acentuada nos tratamentos sem o uso da assistência de ar. Em relação à produtividade não houve diferenças entre os tratamentos com aplicação de fungicidas, porém houve incremento na produtividade para os tratamentos com assistência de ar.This research aimed to evaluate the effects of chemical control of the rust and deposition fungicide sprayed under four air speed in spray boom on soybean crop (Glycine max L.. Two experiments were carried out in FCA/UNESP-Botucatu/SP (season 2007/08. The tracer used in the spray solution was copper oxychloride (50% of the metallic copper. It was measured by spectrophotometer of atomic absorption equipment. The targets were fixed on

  8. Evaluation of Kerma rate in the skin entrance in interventional procedures guided by fluoroscopy

    Medeiros, Regina Bitelli; Alves, Fatima Faloppa Rodrigues; Ruberti Filha, Eny M.

    2005-01-01

    Interventional therapeutic procedures guided by fluoroscopy are responsible for delayed exposure to radiation of professionals and patients. The technology employed on generation of the pulsed fluoroscopy can be an important tool of protection used for reducing the exposure time. It generates constant width and varied frequency pulse or width pulse or varied frequency for a constant frequency. The typical doses into the skin and its relationship with the quality of the images in the various technical and operational conditions should be known by the professionals so that they can optimize them. Generated radiation doses were evaluated using the Toshiba Infinitix equipment used in invasive cardiology procedures and electrophysiological studies through the Kerma rate at the entrance of the patient's skin measured throughout the year of 2004. With these information shall be set out the criteria for the decision of the technical-operational conditions that allow minimizing of dose

  9. Measurements of air kerma index in computed tomography: a comparison among methodologies

    Alonso, T. C.; Mourao, A. P.; Da Silva, T. A., E-mail: alonso@cdtn.br [Universidade Federal de Minas Gerais, Programa de Ciencia y Tecnicas Nucleares, Av. Pres. Antonio Carlos 6627, Pampulha, 31270-901 Belo Horizonte, Minas Gerais (Brazil)

    2016-10-15

    Computed tomography (CT) has become the most important and widely used technique for diagnosis purpose. As CT exams impart high doses to patients in comparison to other radiologist techniques, reliable dosimetry is required. Dosimetry in CT is done in terms of air kerma index in air or in a phantom measured by a pencil ionization chamber under a single X-ray tube rotation. In this work, a comparison among CT dosimetric quantities measured by an UNFORS pencil ionization chamber, MTS-N RADOS thermoluminescent dosimeters and GAFCHROMIC XR-CT radiochromic film was done. The three dosimetric systems were properly calibrated in X-ray reference radiations in a calibration laboratory. CT dosimetric quantities were measured in CT Bright Speed GE Medical Systems Inc., scanner in a PMMA trunk phantom and a comparison among the three dosimetric techniques was done. (Author)

  10. Evaluation of skin entry kerma in radiological examinations at the Hospital de Clinicas, Parana, Brazil

    Porto, Lorena E.; Schelin, Hugo R.; Santos, Amanda C. dos; Bunick, Ana Paula; Paschuk, Sergei; Denyak, Valeriy; Tilly Junior, Joao G.; Khoury, Helen J.

    2011-01-01

    This paper evaluates the skin entry dose of pediatric and adults patients when submitted to radiological examinations at the Hospital de Clinicas do Parana, Brazil, as part integrate of the data assessment of International Atomic Energy Agency (IAEA) for Latin America. It was performed measurements of dose for evaluation of skin entry kerma in pediatric patients in thorax AP/PA examinations, adults of thorax in AP/PA, cranio caudal mammography and median lateral and patients of computerized tomography in examination of head, thorax and abdomen. The obtained data demonstrate the necessity of verification of diagnostic analysis standards. The great value amplitudes demonstrate the incompatibility of examination executions with those recommended by the literature. The dose values presented partially inside the range recommended and the other over the expected for the due examination when compared with the literature

  11. Measurements of air kerma index in computed tomography: a comparison among methodologies

    Alonso, T. C.; Mourao, A. P.; Da Silva, T. A.

    2016-10-01

    Computed tomography (CT) has become the most important and widely used technique for diagnosis purpose. As CT exams impart high doses to patients in comparison to other radiologist techniques, reliable dosimetry is required. Dosimetry in CT is done in terms of air kerma index in air or in a phantom measured by a pencil ionization chamber under a single X-ray tube rotation. In this work, a comparison among CT dosimetric quantities measured by an UNFORS pencil ionization chamber, MTS-N RADOS thermoluminescent dosimeters and GAFCHROMIC XR-CT radiochromic film was done. The three dosimetric systems were properly calibrated in X-ray reference radiations in a calibration laboratory. CT dosimetric quantities were measured in CT Bright Speed GE Medical Systems Inc., scanner in a PMMA trunk phantom and a comparison among the three dosimetric techniques was done. (Author)

  12. Simulation evaluation of NIST air-kerma rate calibration standard for electronic brachytherapy.

    Hiatt, Jessica R; Rivard, Mark J; Hughes, H Grady

    2016-03-01

    Dosimetry for the model S700 50 kV electronic brachytherapy (eBT) source (Xoft, Inc., a subsidiary of iCAD, San Jose, CA) was simulated using Monte Carlo (MC) methods by Rivard et al. ["Calculated and measured brachytherapy dosimetry parameters in water for the Xoft Axxent x-ray source: An electronic brachytherapy source," Med. Phys. 33, 4020-4032 (2006)] and recently by Hiatt et al. ["A revised dosimetric characterization of the model S700 electronic brachytherapy source containing an anode-centering plastic insert and other components not included in the 2006 model," Med. Phys. 42, 2764-2776 (2015)] with improved geometric characterization. While these studies examined the dose distribution in water, there have not previously been reports of the eBT source calibration methods beyond that recently reported by Seltzer et al. ["New national air-kerma standard for low-energy electronic brachytherapy sources," J. Res. Natl. Inst. Stand. Technol. 119, 554-574 (2014)]. Therefore, the motivation for the current study was to provide an independent determination of air-kerma rate at 50 cm in air K̇air(d=50 cm) using MC methods for the model S700 eBT source. Using CAD information provided by the vendor and disassembled sources, an MC model was created for the S700 eBT source. Simulations were run using the mcnp6 radiation transport code for the NIST Lamperti air ionization chamber according to specifications by Boutillon et al. ["Comparison of exposure standards in the 10-50 kV x-ray region," Metrologia 5, 1-11 (1969)], in air without the Lamperti chamber, and in vacuum without the Lamperti chamber. K̇air(d=50 cm) was determined using the *F4 tally with NIST values for the mass energy-absorption coefficients for air. Photon spectra were evaluated over 2 π azimuthal sampling for polar angles of 0° ≤ θ ≤ 180° every 1°. Volume averaging was averted through tight radial binning. Photon energy spectra were determined over all polar angles in both air and vacuum using

  13. Air kerma standardization for diagnostic radiology in a secondary standard laboratory

    Ramos, Manoel M.O.; Peixoto, J. Guilherme P.; Lopes, Ricardo T.

    2009-01-01

    The demand for calibration services and quality control in diagnostic radiology has grown in the country since the publication of the governmental regulation 453, issued by the Brazilian Ministry of Health in 1998. At that time, to produce results facing the new legislation, many laboratories used different standards and radiation qualities, some of which could be inadequate. The international standards neither supplied consistent radiation qualities and standardization for the different types of equipment available. This situation changed with the publication of the new edition of the IEC 61267 standard, published in 2005. The objective of this work was to implement the standardization of the air kerma for the unatenuated qualities (RQR) of IEC 61267 in the National Laboratory of Metrology of the Ionizing Radiations (LNMRI) of the Institute of Radiation Protection and Dosimetry (IRD). Technical procedures were developed together with uncertainty budget. Results of interlaboratory comparisons demonstrate that the quantity is standardized and internationally traceable. (author)

  14. Development of a calibration methodology and tests of kerma area product meters

    Costa, Nathalia Almeida

    2013-01-01

    The quantity kerma area product (PKA) is important to establish reference levels in diagnostic radiology exams. This quantity can be obtained using a PKA meter. The use of such meters is essential to evaluate the radiation dose in radiological procedures and is a good indicator to make sure that the dose limit to the patient's skin doesn't exceed. Sometimes, these meters come fixed to X radiation equipment, which makes its calibration difficult. In this work, it was developed a methodology for calibration of PKA meters. The instrument used for this purpose was the Patient Dose Calibrator (PDC). It was developed to be used as a reference to check the calibration of PKA and air kerma meters that are used for dosimetry in patients and to verify the consistency and behavior of systems of automatic exposure control. Because it is a new equipment, which, in Brazil, is not yet used as reference equipment for calibration, it was also performed the quality control of this equipment with characterization tests, the calibration and an evaluation of the energy dependence. After the tests, it was proved that the PDC can be used as a reference instrument and that the calibration must be performed in situ, so that the characteristics of each X-ray equipment, where the PKA meters are used, are considered. The calibration was then performed with portable PKA meters and in an interventional radiology equipment that has a PKA meter fixed. The results were good and it was proved the need for calibration of these meters and the importance of in situ calibration with a reference meter. (author)

  15. Geochronology and thermochronology by the 40Ar/39Ar method

    McDougall, I.; Harrison, T.M.

    1988-01-01

    This work is a response to the authors' belief that there is a need for a monograph on 40 Ar/ 39 Ar dating to provide concise knowledge concerning the application of this method to geological studies. They aim to provide a reasonably comprehensive but by no means exhaustive coverage of the principles and practices of 40 Ar/ 39 Ar dating, with emphasis on interpretation of results. In attempting to provide an overview of the current state of knowledge, they commonly cite examples from the available literature. They draw rather heavily upon their own work, because they feel comfortable with their own examples. (author)

  16. Modelagem de um condicionador de ar de alta precisão para uso em processamento agrícola Modeling of a high precision air conditioner for use in agricultural processing

    Mauri Fortes

    2006-08-01

    Full Text Available Apresenta-se neste trabalho, estudo detalhado sobre a modelagem de um condicionador de ar com controle acurado de temperatura e umidade relativa. Desenvolveu-se um programa de computador que permite predizer o comportamento do sistema sob diferentes condições psicrométricas e de vazão do ar de entrada. O modelo global físico-matemático inclui equações de balanço de massa e de energia para três diferentes volumes de controle que compõem o condicionador. Modelaram-se os processos de mistura, evaporação (ou condensação simultânea de uma superfície d'água e de uma gota e o aquecimento de corrente de ar, separadamente. Propõem-se expressões semi-empíricas simples para os coeficientes de transferência de calor e massa inerentes ao processo de evaporação sobre uma superfície d'água e um modelo simplificado para o sistema de spray. Construiu-se um condicionador de ar no qual foram feitos testes experimentais para o ajuste das constantes que aparecem nas expressões para os coeficientes de transferência. Os dados obtidos validaram o modelo global, com precisão aceitável para projetos de engenharia.In this work, a detailed procedure for the analysis of an accurately controlled air conditioner is presented. A computer program, that allows predicting the behavior of the system under different psychrometric conditions and different input air mass flow rates, was developed. The global physical-mathematical model includes mass and energy conservation equations for three different control volumes that compose the conditioner. Thus, the processes of mixture of air, simultaneous evaporation (or condensation from a water surface and from a drop, and the air-stream heating are modeled separately. Simple semi-empiric expressions for heat and mass coefficients inherent to the evaporation process on a water surface are proposed as well a simplified model for the spray system. Experimental tests made on an air-conditioner allowed to obtain

  17. OCORRÊNCIA E DURAÇÃO DAS TEMPERATURAS MÍNIMAS DIÁRIAS DO AR PREJUDICIAIS À FECUNDAÇÃO DAS FLORES DO ARROZ EM SANTA MARIA, RS: .II - ESTIMATIVA DO NÚMERO DIÁRIO DE HORAS COM TEMPERATURAS BAIXAS

    Valduino Estefanel

    1991-12-01

    Full Text Available O presente trabalho objetivou testar os modelos analíticos utilizados por ANGELOCCI et al (1979, HELDWEIN (1983 e os propostos com ajustes para o verão de Santa Maria (Santa Maria, I, II e III para estimar o número diário de horas com temperatura do ar ≤ 10, 11, 12, 13, 14, 15, 16 e 17,0°C, para os meses de dezembro, Janeiro, fevereiro e março para Santa Maria, RS. A comparação entre os valores obtidos diretamente dos termogramas e os estimados por cinco modelos analíticos (ANGELOCCI et al, 1979; HELDWEIN,1983; Santa Maria I, II e III foi feita em função dos valores médios diários de horas dos dias com temperaturas baixas, coeficientes de determinação, linear e angular da equação de 1° grau entre os valores reais e os estimados. Verifica-se que é possível estimar, com precisão satisfatória, o número diário de horas com temperatura do ar ≤ 17, 16, 15, 14, 13 e 12,0°C, utilizando os modelos analíticos de ANGELOCCI et al (1979 e o Santa Maria III.

  18. Geological Dating by 40 Ar - 39 Ar method

    Vollbert Romero, M.E.

    1992-01-01

    The isotope 40 K is radioactive, it decays to 40 Ar stable. The number of 40 Ar atoms produced from 40 K, permits to calculate the date of rocks and minerals. This dating technique is named 'Conventional K-Ar Dating Method'. The 40 Ar - 39 Ar dating method permits to calculate the age of rocks and minerals eliminating the limitation of the K-Ar method by calculating potassium and argon concentrations in a single measurement of the ratio of argon isotopes. In this work, the irradiation of the sample with fast neutrons in the nuclear reactor was established. 39 Ar is obtained from the induced reaction 39 K (n,p) 39 Ar. Thus the ration of 40 Ar - 39 Ar allows to obtain the date of rocks and minerals. This ratio was measured in a mass spectrometer. If the measurement of argon concentration in the sample is carried out at different increasing temperature values, it is possible to get information of paleotemperatures. The number of atoms 39 Ar is a function of the number 39 K atoms, irradiation time, neutrons flux, its energy E and the capture cross section σ of 39 K. These parameters are calculate indirectly by obtaining the so called 'J value ' by using a standard mineral with known age (HD-BI y Biot-133), this mineral is irradiated together with the unknown age sample. The values of 'J' obtained are in the interval of 2.85 a 3.03 (x 10 - 3)J/h. Rocks from 'Tres Virgenes' were dated by the method described in this work, showing an agreement with previous values of different authors. The age of this rocks are from Cenozoico era, mainly in the miocene period. (Author)

  19. Behavior of Eucalyptus grandis and E. cloeziana seedlings grown in arsenic-contaminated soil Comportamento de mudas de E. grandis E. eucalyptus cloeziana cultivadas em solo contaminado por arsênio

    Roseli Freire Melo

    2010-06-01

    Full Text Available Arsenic has been considered the most poisonous inorganic soil pollutant to living creatures. For this reason, the interest in phytoremediation species has been increasing in the last years. Particularly for the State of Minas Gerais, where areas of former mining activities are prone to the occurrence of acid drainage, the demand is great for suitable species to be used in the revegetation and "cleaning" of As-polluted areas. This study was carried out to evaluate the potential of seedlings of Eucalyptus grandis (Hill Maiden and E. cloeziana F. Muell, for phytoremediation of As-polluted soils. Soil samples were incubated for a period of 15 days with different As (Na2HAsO4 doses (0, 50, 100, 200, and 400 mg dm-3. After 30 days of exposure the basal leaves of E. cloeziana plants exhibited purple spots with interveinal chlorosis, followed by necrosis and death of the apical bud at the 400 mg dm-3 dose. Increasing As doses in the soil reduced root and shoot dry matter, plant height and diameter in both species, although the reduction was more pronounced in E. cloeziana plants. In both species, As concentrations were highest in the root system; the highest root concentration was found in E. cloeziana plants (305.7 mg kg-1 resulting from a dose of 400 mg dm-3. The highest As accumulation was observed in E. grandis plants, which was confirmed as a species with potential for As phytoextraction, tending to accumulate As in the root system and stem.O arsênio (As tem sido considerado o poluente inorgânico de solo mais tóxico para os seres vivos, razão pela qual o interesse por espécies indicadoras e fitorremediadoras tem aumentado nos últimos anos. Particularmente para o Estado de Minas Gerais, que apresenta áreas remanescentes de atividade mineradora sujeitas à ocorrência de drenagem ácida, existe grande demanda por espécies com potencial para serem utilizadas na revegetação e "limpeza" de substratos contaminados por esse metaloide. Este

  20. A conversion method of air kerma from the primary, scatter, and leakage radiations to effective dose for calculating x-ray shielding barriers in mammography

    Kharrati, Hedi

    2005-01-01

    In this study, a new approach has been introduced for derivation of the effective dose from air kerma to calculate shielding requirements in mammography facilities. This new approach has been used to compute the conversion coefficients relating air kerma to the effective dose for the mammography reference beam series of the Netherlands Metrology Institute Van Swinden Laboratorium, National Institute of Standards and Technology, and International Atomic Energy Agency laboratories. The results show that, in all cases, the effective dose in mammography energy range is less than 25% of the incident air kerma for the primary and the scatter radiations and does not exceed 75% for the leakage radiation

  1. 40Ar/39Ar geochronology of terrestrial pyroxene

    Ware, Bryant; Jourdan, Fred

    2018-06-01

    Geochronological techniques such as U/Pb in zircon and baddeleyite and 40Ar/39Ar on a vast range of minerals, including sanidine, plagioclase, and biotite, provide means to date an array of different geologic processes. Many of these minerals, however, are not always present in a given rock, or can be altered by secondary processes (e.g. plagioclase in mafic rocks) limiting our ability to derive an isotopic age. Pyroxene is a primary rock forming mineral for both mafic and ultramafic rocks and is resistant to alteration process but attempts to date this phase with 40Ar/39Ar has been met with little success so far. In this study, we analyzed pyroxene crystals from two different Large Igneous Provinces using a multi-collector noble gas mass spectrometer (ARGUS VI) since those machines have been shown to significantly improve analytical precision compared to the previous single-collector instruments. We obtain geologically meaningful and relatively precise 40Ar/39Ar plateau ages ranging from 184.6 ± 3.9 to 182.4 ± 0.8 Ma (2σ uncertainties of ±1.8-0.4%) and 506.3 ± 3.4 Ma for Tasmanian and Kalkarindji dolerites, respectively. Those data are indistinguishable from new and/or published U-Pb and 40Ar/39Ar plagioclase ages showing that 40Ar/39Ar dating of pyroxene is a suitable geochronological tool. Scrutinizing the analytical results of the pyroxene analyses as well as comparing them to the analytical result from plagioclase of the same samples indicate pure pyroxene was dated. Numerical models of argon diffusion in plagioclase and pyroxene support these observations. However, we found that the viability of 40Ar/39Ar dating approach of pyroxene can be affected by irradiation-induced recoil redistribution between thin pyroxene exsolution lamellae and the main pyroxene crystal, hence requiring careful petrographic observations before analysis. Finally, diffusion modeling show that 40Ar/39Ar of pyroxene can be used as a powerful tool to date the formation age of mafic

  2. Determinação espectrofotométrica do arsênio em solo da cidade de Santana-AP usando o método do dietilditiocarbamato de prata (SDDC modificado Arsenic spectrophotometric determination in soil of the Santana-AP city using the silver diethyldithiocarbamate (SDDC modified method

    Simone de Fátima Pinheiro Pereira

    2009-01-01

    Full Text Available Várias toneladas de rejeito de manganês contendo arsênio, gerado por uma empresa de mineração, foram utilizadas como aterro de ruas da cidade de Santana-AP. A possibilidade de exposição das pessoas residentes nessas localidades levou ao estudo de quantificação de arsênio total nos solos. Após a digestão, os teores de arsênio foram quantificados por espectrofotometria de absorção molecular usando um sistema automático de geração de hidretos (HG-MAS, diciclohexilamina/CHCl3 como solvente do dietilditiocarbamato de prata (SDDC e KBH4 como redutor. O método apresentou bons resultados com sensibilidade (ε de 1,10 10(4 L.mol-1.cm-1, estabilidade de 2,96% e outras vantagens em relação ao método oficial. O método foi aplicado em amostras de referência de solo com recuperação de 98,82 % (N=10. As análises de solos mostraram que do total de amostras analisadas 94,74 % apresentaram concentração de arsênio acima do valor editado pela CETESB para solo residencial (50 mg.kg-1 com valor médio de 682,96 mg.kg-1, variando de 48,08 mg.kg-1 a 1.713,00 mg.kg-1 que comprova a contaminação do solo pelo arsênio.Several tons of manganese residues containing arsenic, generated by a mining company, were used as streets landfill in Santana-Ap city. The possibility of exposure of people living in these villages has led to the study of quantification of total arsenic in the soil. After digestion, the levels of arsenic were quantified by molecular absorption spectrophotometry using a hydrides generation automatic system (HG-MAS, dicyclohexilamine/CHCl3 as silver diethyldithiocarbamate (SDDC solvent and KBH4 as reducer. The method presented good results with sensitivity (ε of 1.10 10(4 l.mol-1.cm-1, stability of 2.96 % and other advantages in relation to the official method. The method was applied to the soil standard samples with recoveries of the 98.82 % (n=10. The soil analysis showed that 94.74 % samples showed arsenic concentrations

  3. Flutuação populacional do bicho-mineiro em cultivares de café arábica resistentes à ferrugem Fluctuation of leaf miner population in resistant arabica coffee cultivars to leaf rust

    Celso Henrique Costa Conceição

    2005-01-01

    Full Text Available A intensidade de infestação pelo bicho-mineiro, Leucoptera coffeella (Guérin-Méneville (Lepidoptera: Lyonetiidae foi investigada nas cultivares Obatã IAC 1669-20 e Tupi IAC 1669-33, com resistência à ferrugem das folhas do cafeeiro, Hemileia vastatrix Berk. et Br., e Ouro Verde Amarelo IAC 4397, suscetível à doença, em ensaios de campo, localizados em Campinas (SP, Brasil. A incidência de ferrugem e a ocorrência de inimigos naturais da praga, assim como o enfolhamento das plantas, foram também observados nas três cultivares. As curvas de flutuação populacional obtidas para Obatã IAC 1669-20 e Tupi IAC 1669-33 revelaram maior incidência do bicho-mineiro entre abril e novembro. Já na cultivar Ouro Verde Amarelo IAC 4397, observaram-se dois picos de infestação, sendo o primeiro em abril-maio e o segundo em agosto-setembro. No entanto, a elevada percentagem de folhas minadas nas cultivares Tupi IAC 1669-33 e Obatã IAC 1669-20 em relação à Ouro Verde Amarelo IAC 4397 não é evidência de maior suscetibilidade à praga, mas sim devido à maior retenção foliar dessas cultivares, em conseqüência da resistência à ferrugem das folhas observada em ambas. De maneira oposta, na cultivar Ouro Verde Amarelo IAC 4397, os sintomas de ataque do bicho-mineiro ocorreram em menor nível especialmente devido a maior queda de folhas. Com base nas diferenças observadas entre as cultivares, sugere-se a adoção de estratégias distintas de manejo da praga.The intensity of infestation of leaf-miner, Leucoptera coffeella (Guérin-Méneville was investigated in coffee cultivars Obatã IAC 1669-20 and Tupi IAC 1669-33, both resistant to the leaf rust agent, Hemileia vastatrix Berk. et Br., and Ouro Verde Amarelo IAC 4397, susceptible to this coffee disease, at field assays in Campinas, SP, Brazil. The incidence of coffee rust and presence of natural enemies, as well as the plant leafiness, were also observed. In Obatã IAC 1669-20 and Tupi

  4. Estudos quimiométricos em amostras de arroz nacional: caracterização do perfil de aminoácidos e sua correlação com o teor de arsénio

    Lopes, Joel Nuno Rodrigues

    2014-01-01

    O arroz é um dos alimentos básicos mais importantes para a população mundial, sendo um dos cereais mais consumidos em todo o mundo. Possui um alto teor em hidratos de carbono devido à alta concentração de amido, contém ainda proteínas, vitaminas, minerais e poucas gorduras. A quantidade de proteína a ingerir é requisito para uma dieta adequada (0,75g/kg/dia), devido ao desempenho vital que esta tem na saúde humana. O arroz pelo seu papel determinante na alimentação mundial faz com que os ami...

  5. Desenvolvimento de controle avançado para processos de aeração por ar difuso visando aplicação em sistemas de tratamento de efluentes

    Tiago Magalhães Soares

    2010-01-01

    Sistemas de aeração são amplamente utilizados em estações de tratamento de esgotos sanitários e efluentes industriais, sendo a configuração mais utilizada os sistemas de lodos ativados. Neste trabalho, buscou-se a implementação e o teste de uma estratégia de controle avançado em um sistema de aeração. Foi utilizado um canal de aeração com recirculação de água como simulação de um tanque de aeração. Para consumir o oxigênio dissolvido na água, foi realizada a dosagem de hipossulfito de sódio n...

  6. Inovação e internacionalização bioindustrial em Minas Gerais 2001-2004: como potencializar oportunidades e avançar rumo a 2020?

    Valéria M. M. Judice

    Full Text Available Visando à formulação de políticas de desenvolvimento bioindustrial em Minas Gerais, o artigo analisa e integra resultados de duas pesquisas realizadas em 2004: uma delas, empírica, sobre a evolução bioindustrial mineira no período 2001-04 e a outra, um estudo de políticas bioindustriais internacionais. Duas constatações da primeira pesquisa são percebidas como oportunidades a serem promovidas, à luz de modelos de políticas internacionais, identificados na segunda pesquisa. Numa amostra de 42 empresas bioindustriais, selecionadas de 75 em operação naquele estado, fica evidente, de um lado, um decréscimo no número de empresas, mas também uma ampliação da capacidade inovadora, indicada pelo surgimento de novos entrantes com maior potencial tecnológico, produção de nível mundial e investimentos venture capital. De outro lado, com relação à internacionalização, constata-se, nas organizações pesquisadas, um incremento das exportações, da intenção de "exportar mais no futuro" e avanços quanto à capacidade de atuação no mercado externo. Após a avaliação e o detalhamento dessas oportunidades, ao final, são propostas políticas para promoção e apoio ao setor bioindustrial, conforme políticas-padrão praticadas em nível internacional.

  7. Preparation and determination of kerma for Iridium 192 sources of low dose rate for brachytherapy; Preparacion y determinacion del kerma de fuentes de iridio-192 de baja tasa de dosis para braquiterapia

    Tendilla, J.I.; Tovar M, V.; Mitsoura, E.; Aguilar H, F.; Alanis M, J. [Instituto Nacional de Investigaciones Nucleares, C.P. 52045-1, Salazar, Esrado de Mexico, D.F. (Mexico)

    2000-07-01

    The practice of Brachytherapy with Iridium-192 sources of low dose rate (0.4 - 0.8 Gy/h) is a technique used in the treatment of diverse illnesses. in this work the preparation, quality control and calibration are presented in terms of kerma in air of Iridium-192 using as target these recycled Iridium-Platinum wires. The targets were obtained as decayed sources of different radio therapeutical centers in the country and they were characterized by Scanning electron microscopy in order to determine their chemical composition. Subsequently it was developed an experimental design to establish the effect of neutron flux, geometrical array and irradiation time over the activity and percentage of the sources homogeneity. The homogeneity was determined by auto radiography and by Gamma spectroscopy. Once the optimal irradiation conditions were established, it is determined the apparent activity and kerma in air using a well type ionization chamber with traceability to a primary laboratory. Iridium-192 sources were obtained with an average homogeneity 96 %, apparent activity 282.129 {+-} 0.531 M Bq and kerma in air 0.03200 {+-} 0.00006 m Gy m/h A. (Author)

  8. Comparison of the standards of air kerma of the OMH and the BIPM for 60Co gamma radiation

    Allisy-Roberts, P.J.; Kessler, C.; Burns, D.T.; Roger, P.; Machula, G.; Csete, I.; Rabus, H.

    2006-09-01

    A direct comparison between the standards for air kerma of the Orszagos Meresugyi Hivatal (OMH) and of the Bureau International des Poids et Mesures (BIPM) has been carried out in the 60 Co radiation beams of the BIPM. The result, expressed as a ratio of the OMH and the BIPM standards for air kerma, indicates a relative difference of 10.9 x 10 -3 with a combined standard uncertainty of 2.2 x 10 -3 . This new result agrees at the level of 0.4 x 10 -3 with the earlier direct comparisons performed in 1986 and 1994, as modified in 2001 by the application of wall and axial non-uniformity correction factors, calculated for the OMH standards using the Monte Carlo method. (authors)

  9. Review of reconstruction of radiation incident air kerma by measurement of absorbed dose in tooth enamel with EPR.

    Wieser, A

    2012-03-01

    Electron paramagnetic resonance dosimetry with tooth enamel has been proved to be a reliable method to determine retrospectively exposures from photon fields with minimal detectable doses of 100 mGy or lower, which is lower than achievable with cytogenetic dose reconstruction methods. For risk assessment or validating dosimetry systems for specific radiation incidents, the relevant dose from the incident has to be calculated from the total absorbed dose in enamel by subtracting additional dose contributions from the radionuclide content in teeth, natural external background radiation and medical exposures. For calculating organ doses or evaluating dosimetry systems the absorbed dose in enamel from a radiation incident has to be converted to air kerma using dose conversion factors depending on the photon energy spectrum and geometry of the exposure scenario. This paper outlines the approach to assess individual dose contributions to absorbed dose in enamel and calculate individual air kerma of a radiation incident from the absorbed dose in tooth enamel.

  10. Review of reconstruction of radiation incident air kerma by measurement of absorbed dose in tooth enamel with EPR

    Wieser, A.

    2012-01-01

    Electron paramagnetic resonance dosimetry with tooth enamel has been proved to be a reliable method to determine retrospectively exposures from photon fields with minimal detectable doses of 100 mGy or lower, which is lower than achievable with cytogenetic dose reconstruction methods. For risk assessment or validating dosimetry systems for specific radiation incidents, the relevant dose from the incident has to be calculated from the total absorbed dose in enamel by subtracting additional dose contributions from the radionuclide content in teeth, natural external background radiation and medical exposures. For calculating organ doses or evaluating dosimetry systems the absorbed dose in enamel from a radiation incident has to be converted to air kerma using dose conversion factors depending on the photon energy spectrum and geometry of the exposure scenario. This paper outlines the approach to assess individual dose contributions to absorbed dose in enamel and calculate individual air kerma of a radiation incident from the absorbed dose in tooth enamel. (author)

  11. Uncertainty evaluation of the kerma in the air, related to the active volume in the ionization chamber of concentric cylinders, by Monte Carlo simulation

    Lo Bianco, A.S.; Oliveira, H.P.S.; Peixoto, J.G.P.

    2009-01-01

    To implant the primary standard of the magnitude kerma in the air for X-ray between 10 - 50 keV, the National Metrology Laboratory of Ionizing Radiations (LNMRI) must evaluate all the uncertainties of measurement related with Victtoren chamber. So, it was evaluated the uncertainty of the kerma in the air consequent of the inaccuracy in the active volume of the chamber using the calculation of Monte Carlo as a tool through the Penelope software

  12. Teor e capacidade máxima de adsorção de arsênio em Latossolos brasileiros Content and maximum capacity of arsenic adsorption in Brazilian Oxisols

    Mari Lucia Campos

    2007-12-01

    Full Text Available A alta toxicidade do As aos animais e humanos e a possibilidade de existência de grande número de áreas contaminadas tornam imprescindível o conhecimento do teor semitotal em solos ditos não-contaminados e dos processos de adsorção do As em solos de carga variável. O objetivo deste trabalho foi determinar o teor e a capacidade máxima de adsorção de As (CMADS AS em Latossolos. O teor total foi determinado pelo método USEPA 3051A, e a CMADS As, com auxílio de isotermas de Langmuir com base nos valores de adsorção obtidos em dose de As (0, 90, 190, 380, 760 e 1.150 µmol L-1 (relação solo:solução final = 1:100, a pH 5,5 e força iônica de 15 mmol L-1. Os 17 Latossolos apresentaram teor médio total de As de 5,92 mg kg-1 e CMADS As média de 2.013 mg kg-1. O teor de argila e os óxidos de Fe e Al apresentaram influência positiva na CMADS As.In view of the toxicity of As for man and animals and the possibility of existence of a great number of contaminated areas it is imperative to know the total As content in soils considered uncontaminated and about As sorption processes in soils of variable charge. The objective of this work was to determine the total content and maximum capacity of As adsorption (CMADS As in Oxisols. The total content was determined by the USEPA 3051A method. The cmADS As was determined by the Langmuir Isotherms using six solution concentrations (0, 0.09, 0.19, 0.38, 0.76, 1.15 mmol L-1 (1:100 soil: solution ratio, pH values 5.5 and ionic strength 15 mmol L-1. In the 17 Oxisols the average total As content was 5.92 mg kg-1 and mean cmADS As was 2.013 mg kg-1. Clay, and Fe and Al oxides content influenced cmADSs positively.

  13. DOSE NÃO USUAL DE VARFARINA PARA ALCANÇAR RNI TERAPÊUTICA EM UMA CRIANÇA DE QUATRO MESES: FATORES DE RISCO NÃO GENÉTICOS AINDA SÃO UM DESAFIO

    Lucas Miyake Okumura

    Full Text Available RESUMO Objetivo: Descreve se uma criança do sexo feminino, com quatro meses de idade, que necessitou de varfarina 0.7 mg/kg/dia (5 mg. Discutem se os fatores de risco clinicamente relevantes para prescrição de altas doses do anticoagulante em crianças. Descrição do caso: Em novembro de 2015, uma criança de 5 kg (36 semanas, pré termo foi admitida no pronto atendimento por status epilepticus e febre. Diazepam, fenitoína e ceftriaxona foram prescritos inicialmente. A pesquisa no líquor revelou presença de sete leucócitos, 150 mg/dL de proteínas, 1 mg/dL de glucose e cocos Gram positivos. Em tomografia de crânio, foram observados sinais hipodensos em cerebelo, lobo temporal e núcleos de base à esquerda, sugerindo vasculite infecciosa por meningite pneumocócica. Após o quadro agudo da encefalite, a criança desenvolveu uma trombose e necessitou de anticoagulação com enoxaparina e, posteriormente, com varfarina. Dez dias de tratamento com o segundo fármaco foram necessários para atingir relação normalizada internacional (RNI terapêutica, tendo sido realizados cinco ajustes de dose desde a primeira prescrição de varfarina. Comentários: Os fatores de risco determinantes para necessidade de doses maiores de varfarina foram idade e uso de nutrição enteral. Fenobarbital e prednisona também podem ter contribuído para o uso de uma das maiores doses de varfarina já relatadas na literatura. A despeito da importância dos testes de polimorfismo genético, os pediatras devem estar atentos para identificar os fatores que contribuem para a prescrição de maiores doses de varfarina, de forma a minimizar os riscos de trombose, reduzindo os custos com internação e exames laboratoriais.

  14. Metrological reliability of the calibration procedure in terms of air kerma using the ionization chamber NE2575

    Guimaraes, Margarete Cristina; Silva, Teogenes Augusto da; Rosado, Paulo H.G.

    2016-01-01

    Metrology laboratories are expected to provide X radiation beams that were established by international standardization organizations to perform calibration and testing of dosimeters. Reliable and traceable standard dosimeters should be used in the calibration procedure. The aim of this work was to study the reliability of the NE 2575 ionization chamber used as standard dosimeter for the air kerma calibration procedure adopted in the CDTN Calibration Laboratory. (author)

  15. Effect of bedside shielding on air-kerma rates around gynecologic intracavitary brachytherapy patients containing 226Ra or 137Cs

    Papin, P.J.; Ramsey, M.J.; LaFontaine, R.L.; LePage, R.P.

    1990-01-01

    An anthropomorphic phantom was implanted with 226Ra or 137Cs gynecologic intracavitary brachytherapy sources. Air-kerma rate measurements were taken at 10-cm increments along a horizontal plane from the side of the bed at 50 cm, 87 cm, and 136 cm heights above the floor. Five portable lead shields were placed at the head, at the foot and along one side of the bed and readings were taken again at the corresponding heights above, below and behind the shields. The readings were normalized to 100-mg Ra equivalence, and air-kerma rate curves were drawn allowing for the comparison of 226Ra and 137Cs with and without lead shields. The data demonstrated that the air-kerma rates for 137Cs were reduced more than those for 226Ra with the use of the portable lead shields. There was four times the transmission with 226Ra than with 137Cs. The optimal placement was with the lateral bedside shields proximal to the head and foot closest to the bed, with the middle shield overlapping in back. The shields at the head and foot should extend out and overlap the bedside shields. The level of the sources should be positioned near the bottom of the shields. This information will provide the medical health physicist with an estimate of air-kerma rates for both 226Ra and 137Cs with and without shielding for evaluating personnel exposures as well as the effectiveness of current shielding in relation to radiation protection requirements in adjacent rooms or hallways

  16. Interlaboratory comparisons in kerma in the air measures and absorbed dose in water using 60Co beams in radiotherapy

    Rosado, Paulo Henrique Goncalves; Silva, Cosme Norival Mello da

    2013-01-01

    In order to ensure that the measures of a quantity have high reliability and traceability interlaboratory comparisons are performed. The LNMRI has participated in several these interlaboratory comparisons. In the period 2000-2013 the LNMRI participated in 5 interlaboratory comparisons for measurement of kerma coefficients in the air and absorbed dose coefficients in the water. The results of interlaboratory comparisons indicate that the measures taken are appropriate to the LNMRI regarding the accuracy and precision measuring of these quantities

  17. Evaluation of the Kerma at the entrance of the labyrin thin in facilities with Co-60 HDR brachytherapy

    Pujades, M. C.; Granero, D.; Ballester, F.; Perez-Calatayud, J.; Vijande, J.

    2013-01-01

    The purpose of this study is to evaluate the kerma's collision at the entrance of the labyrinth adapting the methodology of the NCRP-151 to a bunker of brachytherapy with Co-60, similar to the one carried out in a previous work with HDR Ir-192. To validate the result is simulated using techniques Monte Carlo (MC) two typical designs of HDR with Co-60 bunker. (Author)

  18. Seasonal variation of air kerma in the 'Vulcano Porto' area (Aeolian Islands, Italy)

    Bellia, S.; Basile, S.; Brai, M. E-mail: mbrai@unipa.it; Hauser, S.; Puccio, P.; Rizzo, S

    2001-02-01

    Air kerma was measured in the 'Vulcano Porto' area of the Vulcano Island, belonging to the Aeolian Islands, in the Mediterranean Sea. Measurements were carried out using thermoluminescence dosimeters. The relationship between observed dose values and source lithology has been assessed. Data show a seasonal variation due to weather conditions but also probably related to features of the soils, making the variation more evident.

  19. Monte Carlo simulations in CT for the study of the surface air kerma and energy imparted to phantoms of varying size and position

    Avilés Lucas, P.; Dance, D. R.; Castellano, I. A.; Vañó, E.

    2004-04-01

    A Monte Carlo computational model of CT has been developed and used to investigate the effect of various physical factors on the surface air kerma length product, the peak surface air kerma, the air kerma length product within a phantom and the energy imparted. The factors investigated were the bow-tie filter and the size, shape and position of a phantom which simulates the patient. The calculations show that the surface air kerma length product and the maximum surface air kerma are mainly dependent on phantom position and decrease along the vertical axis of the CT plane as the phantom surface moves away from the isocentre along this axis. As a result, measurements using standard body dosimetry phantoms may underestimate the skin dose for real patients. This result is specially important for CT fluoroscopic procedures: for an adult patient the peak skin dose can be 37% higher than that estimated with a standard measurement on the body AAPM (American Association of Physicists in Medicine) phantom. The results also show that the energy imparted to a phantom is mainly influenced by phantom size and is nearly independent of phantom position (within 3%) and shape (up to 5% variation). However, variations of up to 30% were found for the air kerma to regions within the AAPM body phantom when it is moved vertically. This highlights the importance of calculating doses to organs taking into account their size and position within the gantry.

  20. NaI(Tl) scintillator detectors stripping procedure for air kerma measurements of diagnostic X-ray beams

    Oliveira, L.S.R. [Centro Tecnológico do Exército, CTEx (Brazilian Army Technological Center), Av. das Américas n° 28705, 23085-470 Rio de Janeiro (Brazil); Instituto de Radioprotecão e Dosimetria, CNEN/IRD (Institute for Radioprotection and Dosimetry, CNEN/IRD), Av. Salvador Allende s/no, P.O. Box 37750, 22783-127 Barra da Tijuca, Rio de Janeiro (Brazil); Conti, C.C., E-mail: ccconti@ird.gov.br [Instituto de Radioprotecão e Dosimetria, CNEN/IRD (Institute for Radioprotection and Dosimetry, CNEN/IRD), Av. Salvador Allende s/no, P.O. Box 37750, 22783-127 Barra da Tijuca, Rio de Janeiro (Brazil); Amorim, A.S.; Balthar, M.C.V. [Centro Tecnológico do Exército, CTEx (Brazilian Army Technological Center), Av. das Américas n° 28705, 23085-470 Rio de Janeiro (Brazil)

    2013-03-21

    Air kerma is an essential quantity for the calibration of national standards used in diagnostic radiology and the measurement of operating parameters used in radiation protection. Its measurement within the appropriate limits of accuracy, uncertainty and reproducibility is important for the characterization and control of the radiation field for the dosimetry of the patients submitted to diagnostic radiology and, also, for the assessment of the system which produces radiological images. Only the incident beam must be considered for the calculation of the air kerma. Therefore, for energy spectrum, counts apart the total energy deposition in the detector must be subtracted. It is necessary to establish a procedure to sort out the different contributions to the original spectrum and remove the counts representing scattered photons in the detector’s materials, partial energy deposition due to the interactions in the detector active volume and, also, the escape peaks contributions. The main goal of this work is to present spectrum stripping procedure, using the MCNP Monte Carlo computer code, for NaI(Tl) scintillation detectors to calculate the air kerma due to an X-ray beam usually used in medical radiology. The comparison between the spectrum before stripping procedure against the reference value showed a discrepancy of more than 63%, while the comparison with the same spectrum after the stripping procedure showed a discrepancy of less than 0.2%.

  1. NaI(Tl) scintillator detectors stripping procedure for air kerma measurements of diagnostic X-ray beams

    Oliveira, L. S. R.; Conti, C. C.; Amorim, A. S.; Balthar, M. C. V.

    2013-03-01

    Air kerma is an essential quantity for the calibration of national standards used in diagnostic radiology and the measurement of operating parameters used in radiation protection. Its measurement within the appropriate limits of accuracy, uncertainty and reproducibility is important for the characterization and control of the radiation field for the dosimetry of the patients submitted to diagnostic radiology and, also, for the assessment of the system which produces radiological images. Only the incident beam must be considered for the calculation of the air kerma. Therefore, for energy spectrum, counts apart the total energy deposition in the detector must be subtracted. It is necessary to establish a procedure to sort out the different contributions to the original spectrum and remove the counts representing scattered photons in the detector's materials, partial energy deposition due to the interactions in the detector active volume and, also, the escape peaks contributions. The main goal of this work is to present spectrum stripping procedure, using the MCNP Monte Carlo computer code, for NaI(Tl) scintillation detectors to calculate the air kerma due to an X-ray beam usually used in medical radiology. The comparison between the spectrum before stripping procedure against the reference value showed a discrepancy of more than 63%, while the comparison with the same spectrum after the stripping procedure showed a discrepancy of less than 0.2%.

  2. Calculation of conversion factor of Kerma in the air for ambient dose equivalent in radiotherapy

    Lima, Marco Antonio Frota

    2000-03-01

    This work aims to estimate the average conversion factor of Kerma in air to H * (10) using photon beams coming from clinic linear accelerators, transmitted through concrete walls of a radiotherapic treatment room. The transmitted photon spectra by both 1 meter and 2 meters concrete walls, in an area of 40 x 40 cm 2 , were calculated when the primary beam impart in an angle of 0 deg. The (secondary) photon beams transmitted respectively by 0,5 meter, 1,0 meter, 1,0 meter and 2,0 meter concrete walls, after they scattered by an angle of 90 deg in a cylindric phantom inside the room, were also determined. Generally, 50 millions of histories were computed for each simulation made for the primary beam. For the 90 deg spread, the number of histories was 100 millions. The computational code used on this work was the MCNP4B. The most common clinic accelerators used on radiotheraphic treatments were used on this work CLINAC-4, CLINAC-6, CLINAC-18 and CLINAC-2500. From the spectra analysis obtained in this work, it was possible to dispose the conversion factor for realistic beams found in radiotherapeutic establishment. (author)

  3. NOTE: Monte Carlo evaluation of kerma in an HDR brachytherapy bunker

    Pérez-Calatayud, J.; Granero, D.; Ballester, F.; Casal, E.; Crispin, V.; Puchades, V.; León, A.; Verdú, G.

    2004-12-01

    In recent years, the use of high dose rate (HDR) after-loader machines has greatly increased due to the shift from traditional Cs-137/Ir-192 low dose rate (LDR) to HDR brachytherapy. The method used to calculate the required concrete and, where appropriate, lead shielding in the door is based on analytical methods provided by documents published by the ICRP, the IAEA and the NCRP. The purpose of this study is to perform a more realistic kerma evaluation at the entrance maze door of an HDR bunker using the Monte Carlo code GEANT4. The Monte Carlo results were validated experimentally. The spectrum at the maze entrance door, obtained with Monte Carlo, has an average energy of about 110 keV, maintaining a similar value along the length of the maze. The comparison of results from the aforementioned values with the Monte Carlo ones shows that results obtained using the albedo coefficient from the ICRP document more closely match those given by the Monte Carlo method, although the maximum value given by MC calculations is 30% greater.

  4. Air kerma standardization for diagnostic radiology, and requirements proposal for calibration laboratories

    Ramos, Manoel Mattos Oliveira

    2009-01-01

    The demand for calibration services and quality control in diagnostic radiology has grown in the country since the publication of the governmental regulation 453, issued by the Ministry of Health in 1998. At that time, to produce results facing the new legislation, many laboratories used different standards and radiation qualities, some of which could be inadequate. The international standards neither supplied consistent radiation qualities and standardization for the different types of equipment available. This situation changed with the publication of the new edition of the IEC 61267 standard, published in 2005. A metrology network was created, but it is not yet accredited by the accreditation organism of the country, INMETRO. The objective of this work was to implement the standardization of the air kerma for the un attenuated qualities (RQR) of IEC 61267, and to develop a requirement proposal for instruments calibration laboratories. Results of interlaboratory comparisons demonstrate that the quantity is standardized and internationally traceable. A laboratory requirement proposal was finalized and it shall be submitted to INMETRO to be used as auxiliary normative document in laboratory accreditation. (author)

  5. Quality image and incident air kerma evaluation in X-ray chest exams

    Campos de O, P. M.; Do Carmo S, P.; De Sousa L, M. A.; Da Silva, T. A.

    2017-10-01

    The procedures optimization for obtaining diagnostic quality images is an important factor to the patients radiation levels submitted to diagnostic radiology examinations was the lowest as reasonably practicable. Two methodologies for image quality parameters evaluation were applied in the routine of three diagnostic radiology clinics (A, B and C), two with digital image processing and one with chemical processing in Belo Horizonte, Brazil. The incident air kerma was evaluated for the radiographic techniques used in the clinic routine chest exams, approved in accordance with European Image Quality Criteria. It was possible to determine that the Fluke Biomedical X-ray Phantom test objects coupled to the Leeds Test Objects (TOR CDR) obtained better results than Gammex s Radiographic Survey Phantom (RSV), because the low and high contrast structures present in the RSV were not visualized in lower energies. The three clinics presented very similar results in all image quality parameters in the evaluation with the TOR CDR test object. However, clinic C presented an low contrast structures result 28.1 % lower than clinical B, although the average Ka,i to obtain their images was 33.4 % superior. The clinic A results present the best relation between image quality and radiation dose in patients. It was verified the optimization doses possibility in diagnostic radiology services with digital processing system, without significant reduction in image quality. Patients submitted to the highest radiation levels belonged to the clinic that presented the worst results in the image quality parameters evaluated. (Author)

  6. Otimização das condições de pré-redução do As(V em extratos do método BCR para quantificação de arsênio por HG-AAS Optimization of pre-reduction conditions of as(V in BCR extracts to quantify arsenic by HG-AAS

    Eduardo Vinícius Vieira Varejão

    2009-08-01

    Full Text Available A determinação de As por espectrometria de absorção atômica com geração de hidretos (HG-AAS constitui um método simples, sensível, preciso e de baixo custo. Entretanto, essa técnica requer a pré-redução das espécies de As(V, o que se obtém através do uso de agentes redutores como o KI. Em extratos contendo agentes oxidantes, a pré-redução do As é comprometida, como acontece em extratos obtidos pela aplicação do método BCR (acrônimo francês para Community Bureau of Reference para a extração sequencial de As em sedimentos. O objetivo deste trabalho foi avaliar as condições de redução do As(V a As(III, de modo a permitir o uso da HG-AAS para a quantificação do arsênio em extratos obtidos a partir do método BCR. Foram avaliadas condições reacionais utilizando KI, L-cisteína e ácido ascórbico. Para cada uma das etapas de extração do método BCR, diferentes condições de pré-redução possibilitaram a detecção quantitativa do As presente. O uso do método BCR para a extração de arsênio em amostras de sedimentos contaminadas e a aplicação das condições de pré-redução do As(V selecionadas, seguida pela detecção por HG-AAS, forneceram percentagens de recuperação entre 91 e 99 %.The determination of As by hydride generation atomic absorption spectroscopy (HG-AAS is a simple, sensitive, precise and low-cost method. However, this technique requires the pre-reduction of the existing As(V species, which is obtained by the use of reducing agents such as KI. In extracts containing oxidizing agents, the pre-reduction of As is impaired, as it occurs in extracts obtained by the BCR (French acronym for Community Bureau of Reference method for the sequential extraction of As in sediments. The objective of this study was to evaluate the conditions for the reduction of As(V to As(III in a way that allows the use of HG-AAS for the quantification of arsenic in extracts obtained using the BCR method. Reaction

  7. Influência da temperatura do ar de secagem e da concentração de agente carreador sobre as propriedades físico-químicas do suco de açaí em pó Influence of drying air temperature and carrier agent concentration on the physicochemical properties of açai juice powder

    Renata Valeriano Tonon

    2009-06-01

    Full Text Available A influência da temperatura do ar de secagem e da concentração de agente carreador sobre as propriedades físico-químicas do suco de açaí em pó produzido por spray drying foi avaliada. O processo foi realizado em um mini spray dryer de bancada e maltodextrina 10DE foi utilizada como agente carreador. A temperatura do ar de secagem variou de 138 a 202 °C e a concentração de maltodextrina variou de 10 a 30%. As características analisadas foram: umidade, higroscopicidade, retenção de antocianinas, cor, distribuição do tamanho de partículas e morfologia. O aumento da temperatura resultou em partículas maiores, menos úmidas, mais higroscópicas e com menor retenção de antocianinas, além de provocar uma diminuição do parâmetro de cor L* e do ângulo de tom H*. O aumento na concentração de maltodextrina resultou em partículas maiores e menos higroscópicas, com maior luminosidade (L*, menores valores de C* e maiores valores de H*. Em relação à morfologia, o aumento da temperatura levou à formação de uma maior quantidade de partículas com superfície lisa, fato atribuído à maior transferência de calor e, consequentemente, à formação mais rápida de uma membrana ao redor da gota atomizada.The objective of this work was to study the influence of inlet air temperature and maltodextrin concentration on the physicochemical properties of açai juice powder produced by spray drying. The process was carried out in a mini spray dryer and the maltodextrin 10DE was used as carrier agent. Inlet air temperature varied from 138 to 202 °C and maltodextrin concentration varied from 10 to 30%. The characteristics analyzed were: moisture content, hygroscopicity, anthocyanin retention, color, particle size distribution, and morphology. The increase in the temperature resulted in particles with larger size, less moisture content, more hygroscopy and with lower anthocyanin retention, besides promoting a reduction in the color

  8. ARS-Media for excel instruction manual

    ARS-Media for Excel Instruction Manual is the instruction manual that explains how to use the Excel spreadsheet ARS-Media for Excel application. ARS-Media for Excel Instruction Manual is provided as a pdf file....

  9. Electron scattering from 36Ar and 40Ar

    Finn, J.M.

    1975-01-01

    The argon isotopes, 36 Ar and 40 Ar, have been investigated using electron scattering at the high-resolution Linac facilities of the National Bureau of Standards. Both elastic scattering and scattering to low-lying states have been observed. A high-pressure, low-volume gas target cell was designed and developed for this experiment. The cell features a transmission geometry and has resolution comparable to solid targets. Spectra were obtained at incident beam energies ranging from 65 to 115 MeV at scattering angles of 92.5 0 and 110 0 . Values obtained for the rms charge radii are 3.327 +- 0.015 and 3.393 +- 0.015 fm for 36 Ar and 40 Ar respectively. A sensitive measurement was made of the difference in the two radii yielding a value of Δ r = 0.079 +- 0.006 fm. The inelastic levels observed are the 1.97 (2 + ) and 4.18 MeV (3 - ) levels in 36 Ar, and the 1.46 (2 + ), 2.52 (2 + ), 3.21 (2 + ), and 3.68 MeV (3 - ) levels in 40 Ar. A Tassie model analysis was made of the inelastic transitions in the DWBA approximation and transition strengths of these levels were extracted

  10. Evaluation of two semi-analytical techniques in air quality applications Avaliação de duas técnicas semi-analíticas em aplicações na qualidade do ar

    Jonas C. Carvalho

    2007-04-01

    Full Text Available In this article an evaluation of two semi-analytical techniques is carried out, considering the quality and accuracy of these techniques in reproducing the ground-level concentration values of passive pollutant released from low and high sources. The first technique is an Eulerian model based on the solution of the advection-diffusion equation by the Laplace transform technique. The second is a Lagrangian model based on solution of the Langevin equation through the Picard Iterative Method. Turbulence parameters are calculated according to a parameterization capable of generating continuous values in all stability conditions and in all heights of the planetary boundary layer. Numerical simulations and comparisons show a good agreement between predicted and observed concentrations values. Comparisons between the two proposed techniques reveal that Lagrangian model generated more accurate results, but Eulerian model demands a lesser computational time.Neste artigo é realizada uma avaliação de duas técnicas semi-analíticas, considerando a qualidade e a exatidão destas técnicas em reproduzir valores de concentração ao nível da superfície de poluentes passivos emitidos a partir de fontes baixas e altas. A primeira técnica é um modelo Euleriano baseado na solução da equação advecção-difusão através da técnica de transformada de Laplace. A segunda é um modelo Lagrangiano baseado na solução da equação de Langevin através do Método Iterativo de Picard. Parâmetros da turbulência são calculados de acordo com uma parametrização capaz de gerar valores contínuos em todas as condições de estabilidade e em todas as alturas na camada limite planetária. Simulações numéricas e comparações mostram uma boa concordância entre valores de concentração previstos e observados. Comparações entre as duas técnicas revelam que o modelo Lagrangiano gera resultados mais precisos, mas o modelo Euleriano exige um menor tempo

  11. Fixação do nitrogênio do ar pelas bactérias que vivem em simbiose com as raízes da centrosema Fixation of the atmospheric nitrogen by bacteria which live symbiotically on centrosema

    J. Casado Montojos

    1963-01-01

    Full Text Available Continuando a série de trabalhos sôbre a quantidade de nitrogênio atmosférico fixada por bactérias que vivem em simbiose com raízes de leguminosas, são relatados os resultados encontrados em centrosema (Centrosema pubescens Benth. Foram utilizados vasos de Mitscherlich, com terra-roxa-misturada. A colheita das plantas foi efetuada por ocasião do florescimento. A parte aérea foi pesada para cálculo da quantidade de massa verde produzida, e, em seguida, juntamente com as raízes, sêca a 60°C até pêso constante. Determinaram-se os teores de nitrogênio na parte aérea e subterrânea das plantas, assim como da terra dos vasos. Os resultados mostraram elevada capacidade de fixação simbiótica de nitrogênio pela centrosema correspondente a cêrca de 204 quilogramas de nitrogênio por hectare.Following a series of research work with the purpose of verifying the amount of atmospheric nitrogen fixed by symbiotic bacteria, the authors report in this paper the results on their research with the leguminous plant Centrosema pubescens Benth. This experiment was conducted in Mitscherlich pots containing terra-roxa-misturada obtained from a 20 cm deep layer of soil taken from the Central Experiment Station "Theodureto de Camargo", in Campinas. The plants were cut in the blooming period, as this is the proper season for turning over green manure crops. The aerial portion of the plants was weighed so as to determine the total production of green matter and then it was dried together with the roots at 60°C. Thus, nitrogen of the total plant was determined and the same analysis was done at the end of the experiment for the soil removed from the pots. According to the results of this experiment, it was found that 204 kilograms of nitrogen per hectare were fixed, showing therefore that centrosema has a high capacity of symbiotic nitrogen fixation.

  12. Regional Suppression of <em>Bactrocera> Fruit Flies (Diptera: Tephritidae in the Pacific through Biological Control and Prospects for Future Introductions into Other Areas of the World

    Roger I. Vargas

    2012-08-01

    Full Text Available <em>Bactrocera> fruit fly species are economically important throughout the Pacific. The USDA, ARS U.S. Pacific Basin Agricultural Research Center has been a world leader in promoting biological control of <em>Bactrocera> spp. that includes classical, augmentative, conservation and IPM approaches. In Hawaii, establishment of <em>Bactrocera> <em>cucurbitae> (Coquillett in 1895 resulted in the introduction of the most successful parasitoid, <em>Psyttalia> <em>fletcheri> (Silvestri; similarly, establishment of <em>Bactrocera> <em>dorsalis> (Hendel in 1945 resulted in the introduction of 32 natural enemies of which <em>Fopius> <em>arisanus> (Sonan, <em>Diachasmimorpha> <em>longicaudata> (Ashmead and <em>Fopius> <em>vandenboschi> (Fullaway were most successful. Hawaii has also been a source of parasitoids for fruit fly control throughout the Pacific region including Australia, Pacific Island Nations, Central and South America, not only for <em>Bactrocera> spp. but also for <em>Ceratitis> and <em>Anastrepha> spp. Most recently, in 2002, <em>F.> <em>arisanus> was introduced into French Polynesia where <em>B.> <em>dorsalis> had invaded in 1996. Establishment of <em>D.> <em>longicaudata> into the new world has been important to augmentative biological control releases against <em>Anastrepha> spp. With the rapid expansion of airline travel and global trade there has been an alarming spread of <em>Bactrocera> spp. into new areas of the world (<em>i.e.>, South America and Africa. Results of studies in Hawaii and French Polynesia, support parasitoid introductions into South America and Africa, where <em>B.> <em>carambolae> and <em>B.> <em>invadens>, respectively, have become established. In addition, <em>P.> <em>fletcheri> is a candidate for biological control of <em>B.> <em>cucurbitae> in Africa. We review past and more

  13. SU-F-T-64: An Alternative Approach to Determining the Reference Air-Kerma Rate from Extrapolation Chamber Measurements

    Schneider, T

    2016-01-01

    Purpose: Since 2008 the Physikalisch-Technische Bundesanstalt (PTB) has been offering the calibration of "1"2"5I-brachytherapy sources in terms of the reference air-kerma rate (RAKR). The primary standard is a large air-filled parallel-plate extrapolation chamber. The measurement principle is based on the fact that the air-kerma rate is proportional to the increment of ionization per increment of chamber volume at chamber depths greater than the range of secondary electrons originating from the electrode x_0. Methods: Two methods for deriving the RAKR from the measured ionization charges are: (1) to determine the RAKR from the slope of the linear fit to the so-called ’extrapolation curve’, the measured ionization charges Q vs. plate separations x or (2) to differentiate Q(x) and to derive the RAKR by a linear extrapolation towards zero plate separation. For both methods, correcting the measured data for all known influencing effects before the evaluation method is applied is a precondition. However, the discrepancy of their results is larger than the uncertainty given for the determination of the RAKR with both methods. Results: A new approach to derive the RAKR from the measurements is investigated as an alternative. The method was developed from the ground up, based on radiation transport theory. A conversion factor C(x_1, x_2) is applied to the difference of charges measured at the two plate separations x_1 and x_2. This factor is composed of quotients of three air-kerma values calculated for different plate separations in the chamber: the air kerma Ka(0) for plate separation zero, and the mean air kermas at the plate separations x_1 and x_2, respectively. The RAKR determined with method (1) yields 4.877 µGy/h, and with method (2) 4.596 µGy/h. The application of the alternative approach results in 4.810 µGy/h. Conclusion: The alternative method shall be established in the future.

  14. Influência da adição da goma arábica em filmes isolados de polímero acrílico: estudo das propriedades de intumescimento e de permeabilidade Influence of arabic gum in acrylic polymer isolated films: study of swelling properties and permeability

    Victor Gustavo Santos Gabas

    2003-12-01

    Full Text Available Goma arábica associada ao polímero acrílico Eudragit RS30D® na formação de filmes isolados foram obtidos e investigados como material potencialmente adequado à liberação modificada de fármacos. Foram preparadas dispersões aquosas de 4% (p/v e o citrato de trietila (20% massa polímero acrílico foi usado como plastificante. Dispersões foram vertidas em placa de Nylon revestida com Teflon® e colocadas em estufa a 60 ºC. A determinação do índice de intumescimento (Ii% em fluidos de simulação gástrica (FSG e intestinal (FSI, além da permeabilidade ao vapor d'água (TVA foram avaliadas. As dispersões propostas apresentaram habilidades filmogênicas. O polissacarídeo favoreceu, proporcionalmente à sua concentração, o grau de hidratação e a permeabilidade ao vapor d'água dos filmes formados. Estas particularidades observadas sugerem que os filmes constituídos por estas associações garantem acessibilidade com maior intensidade, quando comparado ao polimetacrilato individualmente, condição essa indispensável para uma biodegradação efetiva, em especial às regiões distais do trato gastrintestinal.Arabic gum combined with polymeric acrylic Eudragit RS30D® in isolated films for film coating, were obtained and investigated as potential material adapted for drug delivery systems. They were prepared aqueous dispersions of 4% (p/v, the triethyl citrate (20% w/w of the methacrylate polymer it was used with plasticizer. Sample of dispersions were poured over plate of Nylon covered with Teflon and placed in an air circulated oven at 60 ºC. Determination of the swelling index (Is% in fluids of gastric (SGF or intestinal simulation or intestinal (SIF, and the permeability to the water vapour (TVA were investigated. An increase in the amount of added polysaccharide favored the degree of hydration/swelling and permeability of the formed films. These observed particularities suggest that the films constituted by these

  15. Poluição do ar e mortalidade em idosos no Município do Rio de Janeiro: análise de série temporal Air pollution and mortality in the elderly in Rio de Janeiro: a time-series analysis

    Regina Paiva Daumas

    2004-02-01

    Full Text Available Este artigo tem por objetivo investigar a associação entre a poluição do ar por partículas e a mortalidade por doenças cardiovasculares e respiratórias entre idosos no Município do Rio de Janeiro. Informações relativas à mortalidade, a concentrações de partículas totais em suspensão (PTS e à meteorologia foram obtidas de fontes de dados secundárias. As contagens diárias de óbitos e os níveis médios diários de PTS para os anos de 1990 a 1993 foram analisados em modelos de regressão de Poisson, que incluíam termos para controle de tendências de longo prazo, flutuações sazonais, dia da semana, temperatura e umidade. Para uma elevação dos níveis de PTS do 10º ao 90º percentil (104,7µg/m³, os riscos relativos para mortalidade por doenças cardiovasculares e respiratórias em idosos foram, respectivamente, 1,04 (IC95%: 0,96-1,13 e 1,10 (IC95%: 0,97-1,26. Embora tenha sido observada uma tendência de aumento de risco, as associações não foram estatisticamente significativas, o que pode ser atribuído, em parte, ao pequeno número de medidas de poluição disponíveis no período analisado.This study investigates the association between particulate air pollution and mortality from cardiovascular and respiratory diseases among the elderly in the city of Rio de Janeiro. Death counts, levels of total suspended particles (TSP, and meteorological data were obtained from secondary databases. Daily counts of deaths and daily TSP levels from 1990 to 1993 were analyzed in Poisson regression models adjusted for long-term temporal trends, seasonality, weekdays, temperature, and humidity. For an increase in TSP levels from the 10th to the 90th percentile (104.7µg/m³, the relative risks for mortality in elderly people from cardiovascular and respiratory diseases were 1.04 (95%CI: 0.96-1.13 and 1.10 (95%CI: 0.97-1.26 respectively. Although an upward trend in risk was observed, the associations were not statistically significant

  16. The ArDM experiment

    Haranczyk, M; Badertscher, A; Boccone, V; Bourgeois, N; Bueno, A; Carmona-Benitez, M C; Chorowski, M; Creus, W; Curioni, A; Daw, E; Degunda, U; Dell'Antone, A; Droge, M; Epprecht, L; Haller, C; Horikawa, S; Kaufmann, L; Kisiel, J; Knecht, L; Laffranchi, M; Lagoda, J; Lazzaro, C; Lightfoot, P; Lozano, J; Lussi, D; Maire, G; Mania, S; Marchionni, A; Mavrokoridis, K; Melgarejo, A; Mijakowski, P; Natterer, G; Navas-Concha, S; Otiougova, P; Piotrowska, A; Polinski, J; de Prado, M; Przewlocki, P; Ravat, S; Regenfus, C; Resnati, F; Robinson, M; Rochet, J; Romero, L; Rondio, E; Rubbia, A; Scotto-Lavina, L; Spooner, N; Viant, T; Trawinski, A; Ulbricht, J; Zalewska, A

    2010-01-01

    The aim of the ArDM project is the development and operation of a one ton double-phase liquid argon detector for direct Dark Matter searches. The detector measures both the scintillation light and the ionization charge from ionizing radiation using two independent readout systems. This paper briefly describes the detector concept and presents preliminary results from the ArDM R&D program, including a 3 l prototype developed to test the charge readout system.

  17. Exposição ao mercúrio e ao arsênio em Estados da Amazônia: síntese dos estudos do Instituto Evandro Chagas/FUNASA Exposure to mercury and arsenic in Amazon States: a summary of studies by the Evandro Chagas Institute/FUNASA

    Elisabeth C. de Oliveira Santos

    2003-06-01

    Full Text Available Este artigo é uma revisão das pesquisas da Seção de Meio Ambiente do Instituto Evandro Chagas/FUNASA sobre exposição ao mercúrio (Hg no vale do rio Tapajós e Estado do Acre, e exposição ao arsênio (As através de resíduos da exploração de manganês (Mn realizada pela ICOMI deixados no Porto de Santana-AP. Em relação ao mercúrio, têm sido pesquisadas populações sob risco através da via respiratória ou alimentar. No primeiro caso, os trabalhadores de casas de compra e venda de ouro têm apresentado teores mais elevados de Hg em urina do que os garimpeiros estudados. No segundo caso, as populações ribeirinhas têm mostrado níveis diferenciados de exposição (Hg em cabelo. Comunidades ribeirinhas situadas em áreas não afetadas pelo mercúrio da garimpagem e com hábitos alimentares semelhantes às de área de risco têm sido avaliadas, visando a construção de parâmetros de normalidade regional. São também pesquisados os teores de Hg em materiais ambientais e na biota aquática. Os estudos de saúde humana e ambiente na cidade de Santana-AP objetivaram avaliar as fontes e possíveis vias de exposição da população da comunidade do Elesbão ao arsênio. Verificou-se a existência de fonte de risco através dos rejeitos de Mn, porém os níveis de As na água consumida pela população mostraram-se dentro dos parâmetros de normalidade. As médias encontradas em sangue e cabelo coincidem com médias de normalidade referidas na literatura, em populações não expostas, e as associações entre variáveis epidemiológicas, avaliação clínico-laboratorial e os teores de arsênio não mostraram significância estatística.This article is a review of the studies carried out by Environmental Section of the Evandro Chagas Institute/FUNASA on mercury (Hg exposure in the Tapajós river basin, and arsenic exposure (As due to residues of the manganese (Mn exploration, performed by ICOMI and left at the port of Santana

  18. Reevaluation of the Solar Wind 36Ar/38Ar Ratio

    Becker, R. H.; Schlutter, D. J.; Rider, P. E.; Pepin, R. O.

    1996-03-01

    The isotopic composition of solar wind (SW) argon is an important parameter in the modeling of the evolution of the terrestrial planet atmospheres. Anders and Grevesse assumed a 36Ar/38Ar ratio for SW of 5.31, essentially equal to that of air. Considerable evidence has since developed which indicates that this ratio is too low. Benkert et al. have reported their best estimate for the recent SW as 5.48 +/- 0.05, determined from measurements of lunar soil 71501. Based on Ar data obtained from surface oxidation of a metal separate from the Weston meteorite and from an uncontrolled etch of lunar sample 67701, reported by our group previously, we consider even this value to be too low. Since values of 5.75 to 5.85 were reported by Black for initial low temperature (fairly high SW 36Ar/38Ar ratio (in the range of ~5.6 to ~5.7), we decided to analyze Kapoeta for its light solar wind gases using the acid-etching techniques developed in our laboratory based on the CSSE procedure of Benkert et al.

  19. Calibration methodology application of kerma area product meters in situ: Preliminary results

    Costa, N. A.; Potiens, M. P. A.

    2014-11-01

    The kerma-area product (KAP) is a useful quantity to establish the reference levels of conventional X-ray examinations. It can be obtained by measurements carried out with a KAP meter on a plane parallel transmission ionization chamber mounted on the X-ray system. A KAP meter can be calibrated in laboratory or in situ, where it is used. It is important to use one reference KAP meter in order to obtain reliable quantity of doses on the patient. The Patient Dose Calibrator (PDC) is a new equipment from Radcal that measures KAP. It was manufactured following the IEC 60580 recommendations, an international standard for KAP meters. This study had the aim to calibrate KAP meters using the PDC in situ. Previous studies and the quality control program of the PDC have shown that it has good function in characterization tests of dosimeters with ionization chamber and it also has low energy dependence. Three types of KAP meters were calibrated in four different diagnostic X-ray equipments. The voltages used in the two first calibrations were 50 kV, 70 kV, 100 kV and 120 kV. The other two used 50 kV, 70 kV and 90 kV. This was related to the equipments limitations. The field sizes used for the calibration were 10 cm, 20 cm and 30 cm. The calibrations were done in three different cities with the purpose to analyze the reproducibility of the PDC. The results gave the calibration coefficient for each KAP meter and showed that the PDC can be used as a reference instrument to calibrate clinical KAP meters.

  20. Ar-Ar dating techniques for terrestrial meteorite impacts

    Kelley, S. P.

    2003-04-01

    The ages of the largest (>100 km) known impacts on Earth are now well characterised. However the ages of many intermediate sized craters (20-100 km) are still poorly known, often the only constraints are stratigraphic - the difference between the target rock age and the age of crater filling sediments. The largest impacts result in significant melt bodies which cool to form igneous rocks and can be dated using conventional radiometric techniques. Smaller impacts give rise to thin bands of melted rock or melt clasts intimately mixed with country rock clasts in breccia deposits, and present much more of a challenge to dating. The Ar-Ar dating technique can address a wide variety of complex and heterogeneous samples associated with meteorite impacts and obtain reasonable ages. Ar-Ar results will be presented from a series of terrestrial meteorite impact craters including Boltysh (65.17±0.64 Ma, Strangways (646±42 Ma), and St Martin (220±32 Ma) and a Late Triassic spherule bed, possibly representing distal deposits from Manicouagan (214±1 Ma) crater. Samples from the Boltysh and Strangways craters demonstrate the importance of rapid cooling upon the retention of old ages in glassy impact rocks. A Late Triassic spherule bed in SW England is cemented by both carbonate and K-feldspar cements allowing Ar-Ar dating of fine grained cement to place a mimimum age upon the age of the associated impact. An age of 214.7±2.5 Ma places the deposit with errors of the age of the Manicouagan impact, raising the possibility that it may represent a distal deposit (the deposit lay around 2000 km away from the site of the Manicouagan crater during the Late Triassic). Finally the limits of the technique will be demonstrated using an attempt to date melt rocks from the St Martin Crater in Canada.

  1. Feldspar 40Ar/39Ar dating of ICDP PALEOVAN cores

    Engelhardt, Jonathan Franz; Sudo, Masafumi; Stockhecke, Mona; Oberhänsli, Roland

    2017-11-01

    Volcaniclastic fall deposits in ICDP drilling cores from Lake Van, Turkey, contain sodium-rich sanidine and calcium-rich anorthoclase, which both comprise a variety of textural zoning and inclusions. An age model records the lake's history and is based on climate-stratigraphic correlations, tephrostratigraphy, paleomagnetics, and earlier 40Ar/39Ar analyses (Stockhecke et al., 2014b). Results from total fusion and stepwise heating 40Ar/39Ar analyses presented in this study allow for the comparison of radiometric constraints from texturally diversified feldspar and the multi-proxy lacustrine age model and vice versa. This study has investigated several grain-size fractions of feldspar from 13 volcaniclastic units. The feldspars show textural features that are visible in cathodoluminescence (CL) or back-scattered electron (BSE) images and can be subdivided into three dominant zoning-types: (1) compositional zoning, (2) round pseudo-oscillatory zoning and (3) resorbed and patchy zoning (Ginibre et al., 2004). Round pseudo-oscillatory zoning records a sensitive alternation of Fe and Ca that also reflects resorption processes. This is only visible in CL images. Compositional zoning reflects anticorrelated anorthite and orthoclase contents and is visible in BSE. Eleven inverse isochron ages from total fusion and three from stepwise heating analyses fit the age model. Four experiments resulted in older inverse isochron ages that do not concur with the model within 2σ uncertainties and that deviate from 1 ka to 17 ka minimum. C- and R-type zoning are interpreted as representing growth in magma chamber cupolas, as wall mushes, or in narrow conduits. Persistent compositions of PO-type crystals and abundant surfaces recording dissolution features correspond to formation within a magma chamber. C-type zoning and R-type zoning have revealed an irregular incorporation of melt and fluid inclusions. These two types of zoning in feldspar are interpreted as preferentially

  2. Estudo de Adequações em um Aeroporto Regional para Alcançar a Eficiência Energética de Forma Renovável

    Artur Rech da Rosa

    2016-04-01

    Full Text Available A sustentabilidade ambiental trata da utilização do meio ambiente, dando oportunidade a ele de se regenerar, ou encontrando meios de substituir a ocupação ambiental por meios renováveis. Nesse contexto, o Aeroporto Regional de Caxias do Sul, que é um empreendimento prestador de serviços de transporte à região da Serra Gaúcha, pode atuar conforme o conceito de desenvolvimento sustentável, desde que ocorra a integração dos critérios ambientais na prática econômica. Nesse contexto, a fotogeração se mostra como uma alternativa para suprir sua demanda energética tornando-o sustentável do ponto de vista deste recurso. Neste trabalho, são determinados a demanda do aeroporto para este tipo de energia, o dimensionamento do sistema fotovoltaico e uma análise da viabilidade econômica do mesmo. A implementação deste sistema pode economizar ao aeroporto 420.248,73 R$/ano e pode gerar o equivalente a R$ 235.653,74/ano em créditos de energia, sendo viável economicamente. Este empreendimento, além de sustentar uma imagem de green airport, pode gerar empregos para especialistas na área e incentivar e propagar a ideia de utilização de energias renováveis

  3. Study and determination of the national dosimetric standards in terms of air kerma for X-rays radiation fields of low and medium-energies; Etude et realisation des references dosimetriques nationales en termes de kerma dans l'air pour les faisceaux de rayons X de basses et moyennes energies

    Ksouri, W

    2008-12-15

    Progress in radiation protection and radiotherapy, and the increased needs in terms of accuracy lead national metrology institutes to improve the standard. For ionizing radiation, the standard is defined by an absolute instrument used for air kerma rate measurement. The aim of the thesis is to establish standards, in terms of air kerma for X-rays beams of low and medium-energies. This work enables to complement the standard beam range of the Laboratoire National Henri Becquerel (LNHB). Two free-air chambers have been developed, WK06 for medium-energy and WK07 for low-energy. The air-kerma rate is corrected by several correction factors. Some are determined experimentally; and the others by using Monte Carlo simulations. The uncertainty budget of the air-kerma rate at one standard deviation has been established. These dosimetric standards were compared with those of counterparts' laboratories and are consistent in terms of degree of equivalence. (author)

  4. Analysis list: Ar [Chip-atlas[Archive

    Full Text Available Ar Gonad,Kidney,Prostate + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/targe...t/Ar.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Ar.5.tsv http://dbarchive.biosciencedbc.jp/...kyushu-u/mm9/target/Ar.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Ar.Gonad.tsv,http://dbarchive.bioscience...dbc.jp/kyushu-u/mm9/colo/Ar.Kidney.tsv,http://dbarchive.bioscienced...bc.jp/kyushu-u/mm9/colo/Ar.Prostate.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Gonad.gml,http://dbarchive.bioscience

  5. Verification of KERMA factor for beryllium at neutron energy of 14.2 MeV based on charged-particle measurement

    Kondo, Keitaro; Ochiai, Kentaro; Murata, Isao; Konno, Chikara

    2008-01-01

    In previous direct measurements of nuclear heating for beryllium induced with DT neutrons, it was pointed out that the calculation with JENDL-3.2 underestimated the measured one by 25%. However, reasons of the discrepancy have not been understood clearly. Recently, we measured the α-particle emission double-differential cross section for beryllium and found that the evaluation of the 9 Be(n,2n + 2α) reaction in nuclear data libraries have some problems. We examined KERMA factors for beryllium deduced with three latest nuclear data libraries: JENDL-3.3, ENDF/B-VII.0 and JEFF-3.1. The partial KERMA factors for 9 Be(n,2n + 2α) reaction channel at incident neutron energy of 14.2 MeV deduced from these libraries were compared with a new partial KERMA factor calculated based on our experimental model. The partial KERMA factor from JENDL-3.3 was smaller by 20% than our experiment-based one. The reason of the discrepancy in the previous nuclear heating measurement comes from the smaller partial KERMA factor in JENDL-3.3, which is caused by significant underestimation of higher energy part of the α-particle emission DDX at forward emission angles

  6. Measurement of conversion coefficients between air Kerma and personal dose equivalent and backscatter factors for diagnostic X-ray beams

    Rosado, Paulo Henrique Goncalves

    2008-01-01

    Two sets of quantities are import in radiological protection: the protection and operational quantities. Both sets can be related to basic physical quantities such as kerma through conversion coefficients. For diagnostic x-ray beams the conversion coefficients and backscatter factors have not been determined yet, those parameters are need for calibrating dosimeters that will be used to determine the personal dose equivalent or the entrance skin dose. Conversion coefficients between air kerma and personal dose equivalent and backscatter factors were experimentally determined for the diagnostic x-ray qualities RQR and RQA recommended by the International Electrotechnical Commission (IEC). The air kerma in the phantom and the mean energy of the spectrum were measured for such purpose. Harshaw LiF-100H thermoluminescent dosemeters (TLD) were used for measurements after being calibrated against an 180 cm 3 Radcal Corporation ionization chamber traceable to a reference laboratory. A 300 mm x 300 mm x 150 mm polymethylmethacrylate (PMMA) slab phantom was used for deep-dose measurements. Tl dosemeters were placed in the central axis of the x-ray beam at 5, 10, 15, 25 and 35 mm depth in the phantom upstream the beam direction Another required parameter for determining the conversion coefficients from was the mean energy of the x-ray spectrum. The spectroscopy of x-ray beams was done with a CdTe semiconductor detector that was calibrated with 133 Ba, 241 Am and 57 Co radiation sources. Measurements of the x-ray spectra were carried out for all RQR and RQA IEC qualities. Corrections due to the detector intrinsic efficiency, total energy absorption, escape fraction of the characteristic x-rays, Compton effect and attenuation in the detector were done aiming an the accurate determination of the mean energy. Measured x-ray spectra were corrected with the stripping method by using these response functions. The typical combined standard uncertainties of conversion coefficients and

  7. Distribution of kerma rate in the air inside of hemodynamic room for typical projections of interventionist cardiology procedures

    Sanchez, Mirtha Elizabet Gamarra

    2008-01-01

    The evaluation of dose to physicians involved in Interventional Cardiology (IC) is an extreme important matter due to the high and non-uniform distribution of dose values. The radiation control during each procedure is complex and the reasons for the high exposures have many different causes. Many international recommendations have already been written aiming the radiation protection optimization in IC. In Brazil, there is not any special orientation for the protection of those occupational persons, nor a specific legislation. The purpose of this work is to evaluate the air kerma rate at critical anatomic regions of the occupationally exposed staff that carry out IC procedures, in representative incidences in order to give subsidies for individual monitoring procedures implementation and to give more information about their radiation protection. The air kerma rate has been measured in the often used condition in the two more common IC procedures namely angiography and coronary angioplasty, using an adult patient simulator irradiated under RAO, LAO and AP projections for fluoro and digital acquisition modes. The measurements have been made in 45 points around the examination table at 5 different representatives heights of: eyes lens, thorax, hands, gonads and knees. AP projection shows the smaller scattered radiation contributions and a more homogeneous exposure distribution. The digital acquisition mode gives air kerma rates about 4 times higher than fluoro mode for LAO projection in the position occupied by the interventionist doctor, the anesthetist and the nursing staff. The most critical anatomic regions are: knees and gonads (without protection). On the physician hands position, values as high as 5 mGy/h have been measured, which can overpass, depending on the number of procedures done, the individual occupational annual limit. Therefore, in IC it is necessary to implement additional protection tools, elaborate safety guides (based on international experiences

  8. Comparison for air kerma from radiation protection gamma-ray beams with Brazilian network: 2016/2017

    Cabral, T.S.; Silva, C.N.M. da, E-mail: tschirn@ird.gov.br [Instituto de Radioproteção e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Potiens, M.P.A. [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil); Soares, C.M.A. [Centro de Desenvolvimento de Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Silveira, R.R. [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil); Khoury, H.; Saito, V. [Universidade Federal de Pernambuco (UFPE), PE (Brazil). Departamento de Energia Nuclear; Fernandes, E. [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Laboratório de Ciências Radiológicas; Cardoso, W.F.; Oliveira, H.P.S. de [Eletrobrás Termonuclear S.A. (Eletronuclear), Rio de Janeiro, RJ (Brazil); Borges, J.C.; Pires, M.A. [MRA Comércio de Instrumentos Eletrônicos Ltda, SP (Brazil); Amorim, A.S. de; Balthar, M. [Centro Tecnológico do Exercito (CTEx), RJ (Brazil)

    2017-07-01

    The results of the comparison involving 9 laboratories in Brazil are reported. The measured quantity was the air kerma in {sup 137}Cs and {sup 60}Co, at the level of radioprotection. The comparison was conducted by the National Laboratory Metrology of Ionizing Radiation (LNMRI/IRD) from October 2016 to March 2017. The largest deviation between the calibration coefficients was 0.8% for {sup 137}Cs and 0.7% for {sup 60}Co. This proficiency exercise proved the technical capacity of the Brazilian calibration network in radiation monitors and the results were used by some in the implementation of the standard ISO / IEC 17025. (author)

  9. Kerma factors and reaction cross sections for n + 12C between 15 and 18 MeV

    Tornow, W.; Chen, Z.M.; Baird, K.; Walter, R.L.

    1988-01-01

    Differential elastic and inelastic (4.44 MeV) neutron scattering cross sections from 12 C are presented at 15.6, 16.8 and 17.3 MeV. The existing 18.2 MeV differential cross-section data were combined with newly measured analysing power data to parametrise neutron scattering at this energy. The 12 C recoil kerma factors were calculated and reaction cross sections were obtained from a phase-shift analysis and coupled channel analyses in the 15.6-18.2 MeV energy range. (author)

  10. Kerma factors and reaction cross sections for n + /sup 12/C between 15 and 18 MeV

    Tornow, W.; Chen, Z.M.; Baird, K.; Walter, R.L.

    1988-07-01

    Differential elastic and inelastic (4.44 MeV) neutron scattering cross sections from /sup 12/C are presented at 15.6, 16.8 and 17.3 MeV. The existing 18.2 MeV differential cross-section data were combined with newly measured analysing power data to parametrise neutron scattering at this energy. The /sup 12/C recoil kerma factors were calculated and reaction cross sections were obtained from a phase-shift analysis and coupled channel analyses in the 15.6-18.2 MeV energy range.

  11. Comparison for Air Kerma from Radiation Protection Gamma-ray Beams with Brazilian Network - 2016/2017

    Cabral, TS; da Silva, CNM; Potiens, MPA; Soares, CMA; Silveira, RR; Khoury, H.; Saito, V.; Fernandes, E.; Cardoso, WF; de Oliveira, HPS; Pires, MA; de Amorim, AS; Balthar, M.

    2018-03-01

    The results of the comparison involving 9 laboratories in Brazil are reported. The measured quantity was the air kerma in 137Cs and 60Co, at the level of radioprotection. The comparison was conducted by the National Laboratory Metrology of Ionizing Radiation (LNMRI/IRD) from October 2016 to March 2017. The largest deviation between the calibration coefficients was 0.8% for 137Cs and 0.7% for 60Co. This proficiency exercise proved the technical capacity of the Brazilian calibration network in radiation monitors and the results were used by some in the implementation of the standard ISO/IEC 17025.

  12. COOMET.RI(I)-K1 comparison of national measurement standards of air kerma for 60Co γ radiation

    Buermann, L.; Oborin, A.V.; Dobrovosky, J.; Milevsky, V.S.; Walwyn Salas, G.; Lapenas, A.

    2009-01-01

    Results are presented of the COOMET key comparison of the national measurement standards of air kerma for 60 Co γ radiation. Participants of the comparison were PTB (Germany, pilot institute), VNIIM (Russia), SMU (Slovakia), BelGIM (Belarus), CPHR (Cuba) and RMTC (Latvia). PTB, VNIIM and SMU had previously taken part in a key comparison with the Bureau International de Poids et Mesures (BIPM) and operated as link laboratories in order to evaluate the degree of equivalence of the participants' results with the key comparison reference value. These data form the basis of the results entered into the BIPM key comparison database for comparison COOMET.RI(I)-K1. (authors)

  13. Alignment and orientation of Ar+ in He+-Ar collisions

    Moudry, B.W.; Yenen, O.; Jaecks, D.H.

    1994-01-01

    We have measured the alignment and orientation parameters of the 2 F 7/2 0 and 2 F 5/2 0 states of Ar + formed in the two-electron process; He + +Ar→He(1s 2 )+Ar + (3p 4 4p'). These have been measured at a collision energy of 0.25 keV/amu and for scattering angles ranging from 0.94 to 3.75 . First, by comparing the orientation prameter for the Ar + [(3p 4 [ 1 D]4p' 2 F 7/2 0 ] and the Ar + [(3p 4 [ 1 D]4p' 2 F 5/2 0 ] states, we have experimentally determined the importance of the spin-dependent interactions for the present collision system, by testing the Percival-Seaton hypothesis of spin independence. If the Percival-Seaton hypothesis holds for this system, the orientation parameter should be J-independent. Secondly, the magnitude of the orientation prameter can be interpreted as resulting from the collective circulation of the unexcited 3p 4 electrons and the excited 4p electron. The direction of this collective circulation is compared to the propensity rule for colliding di-atom systems. (orig.)

  14. Ar-39/Ar-40 systematics of Allende inclusions

    Herzog, G.F.; Rutgers University, New Brunswick, NJ); Bence, A.E.

    1980-01-01

    A laser microprobe was used to measure the Ar isotopic contents of individual mineral grains in four neutron-irradiated Allende samples: two coarse-grained Ca-Al-rich inclusions, one fine-grained Ca-Al-rich inclusion, and one sample with matrix and miscellaneous chondrules. The following K-Ar ages (G.y.) were obtained after degassing low Ar retentive sites by preheating the samples for one hour at 675 C: matrix, 3.5 + or - 0.2 three miscellaneous chondrules, 4.4 + or - 0.1, 4.0 + or - 0.1, and 4.4 + or - 0.1 and the fine-grained inclusion, 4.5 + or - 0.2. The minerals in the coarse-grained Ca-Al-rich inclusions have ubiquitous chlorine, less than 10 ppm K and apparent ages ranging upwards from 4.6 G.y. to well over 10 G.y. Possible explanations for these apparent ages are atmospheric contamination, the decay of K-40 prior to the formation of the solar system, and the trapping of radiogenic Ar-40 lost by the matrix

  15. Determination of Ar metastable atom densities in Ar and Ar/H2 inductively coupled low-temperature plasmas

    Fox-Lyon, N; Knoll, A J; Oehrlein, G S; Franek, J; Demidov, V; Koepke, M; Godyak, V

    2013-01-01

    Ar metastable atoms are important energy carriers and surface interacting species in low-temperature plasmas that are difficult to quantify. Ar metastable atom densities (N Ar,m ) in inductively coupled Ar and Ar/H 2 plasmas were obtained using a model combining electrical probe measurements of electron density (N e ) and temperature (T e ), with analysis of spectrally resolved Ar plasma optical emission based on 3p → 1s optical emission ratios of the 419.8 nm line to the 420.1 nm line. We present the variation of N Ar,m as the Ar pressure and the addition of H 2 to Ar are changed comparatively to recent adsorption spectroscopy measurements. (paper)

  16. Determination of the conversion coefficient for ambient dose equivalent, H(10), from air kerma measurements; Determinacion del coeficiente de conversion para la dosis equivalente ambiental, H*(10), a partir de mediciones de kerma en aire

    Gonzalez J, F. [UNAM, Facultad de Ciencias, Circuito Exterior, Ciudad Universitaria, 04510 Ciudad de Mexico (Mexico); Alvarez R, J. T., E-mail: trinidad.alvarez@inin.gob.mx [ININ, Departamento de Metrologia de Radiaciones Ionizantes, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2015-09-15

    Namely the operational magnitudes can be determined by the product of a conversion coefficient by exposure air kerma or fluence, etc. In particular in Mexico for the first time is determined the conversion coefficient (Cc) for operational magnitude Environmental Dose Equivalent H(10) by thermoluminescence dosimetry (TLD) technique. First 30 TLD-100 dosimeters are calibrated in terms of air kerma, then these dosimeters are irradiated inside a sphere ICRU type of PMMA and with the aid of theory cavity the absorbed dose in PMMA is determined at a depth of 10 mm within the sphere D{sub PMMA}(10), subsequently absorbed dose to ICRU tissue is corrected and the dose equivalent H(10) is determined. The Cc is determined as the ratio of H(10)/K{sub a} obtaining a value of 1.20 Sv Gy{sup -1} with a u{sub c}= 3.66%, this being consistent with the published value in ISO-4037-3 of 1.20 Sv Gy{sup -1} with a u{sub c}= 2%. (Author)

  17. Determination of average conversion coefficients between kerma in air and H⁎(10) using primary and secondary X-ray beams and transmitted in the diagnostic radiology energy range

    Santos, Josilene C.; Gonzalez, Alejandro H.L.; Costa, Paulo R.

    2016-01-01

    Brazilian regulation establishes 1.14 Sv/Gy as unique conversion coefficient to convert air-kerma into the operational quantity ambient dose equivalent H⁎(10) disregarding its beam quality dependence. The present study computed mean conversion coefficients from primary, secondary and transmitted X-ray beams through barite mortar plates used in shielding of dedicated chest radiographic facilities in order to improve the current assessment of H⁎(10). To compute the mean conversion coefficients, the weighting of conversion coefficients corresponding to monoenergetic beams with the spectrum energy distribution in terms of air-kerma was considered. The maximum difference between the obtained conversion coefficients and the constant value recommended in national regulation is 53.4%. The conclusion based on these results is that a constant coefficient is not adequate for deriving the H⁎(10) from air-kerma measurements. (author)

  18. Standardization of 40Ar-39Ar dating facility at KDMIPE, ONGC, Dehradun

    Rathore, S.S.; Singh, M.P.; Vijan, A.R.; Bansal, M.; Prabhu, B.N.; Misra, K.N.

    2003-01-01

    In the pursuit of acquiring state of the art technology, efforts were being made for last more than two years to establish 40 Ar- 39 Ar dating facility at KDMIPE. The 40 Ar- 39 Ar dating technique is an analytical conversion of the conventional K-Ar dating method. In this method, the sample to be dated is first irradiated in a nuclear reactor to transform a portion of 39 K to 39 Ar by the fast neutron reaction i.e. 39 K(n, p) 39 Ar. After irradiation, the sample is placed in an ultra-high vacuum system and the argon extracted from it by fusion is purified and analyzed isotopically in a mass spectrometer. The relative abundances of 40 Ar, 39 Ar, 37 Ar and 36 Ar are measured. The 40 Ar/ 39 Ar K is determined, where 40 Ar is the radiogenic argon, and 39 Ar K is the 39 Ar produced from 39 K during the irradiation. The 40 Ar/ 39 Ar K ratio is proportional to the 40 Ar/ 40 K ratio in the sample and, therefore, is proportional to age

  19. AR DOC: Augmented reality documentaries

    Vistisen, Peter

    2014-01-01

    Augmented Reality Documentaries (AR DOC) er et ’lille’ Shareplay projekt (ansøgte midler augmented reality cross media løsninger, til at skabe engagerende publikumsformidling...... indenfor oplevelsesindustrien. Projektet har genereret ny viden omkring, hvordan fysisk og digital formidling kan understøttes via Augmented Reality som formidlingsformat....

  20. ARS-Media for Excel

    ARS-Media for Excel is an ion solution calculator that uses Microsoft Excel to generate recipes of salts for complex ion mixtures specified by the user. Generating salt combinations (recipes) that result in pre-specified target ion values is a linear programming problem. Thus, the recipes are genera...

  1. "Ars Electronica 2009" / Raivo Kelomees

    Kelomees, Raivo, 1960-

    2009-01-01

    30. "Ars Electronica" festival "Human Nature" ("Inimese loomus") Linzis. Osaka ülikooli professori Hiroshi Ishiguro mehaanilis-digitaalsest nukust. Hübriidkunsti kategoorias peapreemia saanud Eduardo Kaci inimtaimest. Konverentsidest. Näitusest "See this Sound", mis oli pühendatud helile kujutavas kunstis

  2. 40Ar/39Ar geochronology at the Instituto de Geociências, USP: instrumentation, analytical procedures, and calibration

    PAULO M. VASCONCELOS

    2002-06-01

    Full Text Available Laser heating 40Ar/39Ar geochronology provides high analytical precision and accuracy, mum-scale spatial resolution, and statistically significant data sets for the study of geological and planetary processes. A newly commissioned 40Ar/39Ar laboratory at CPGeo/USP, São Paulo, Brazil, equips the Brazilian scientific community with a new powerful tool applicable to the study of geological and cosmochemical processes. Detailed information about laboratory layout, environmental conditions, and instrumentation provides the necessary parameters for the evaluation of the CPGeo/USP 40Ar/39Ar suitability to a diverse range of applications. Details about analytical procedures, including mineral separation, irradiation at the IPEN/CNEN reactor at USP, and mass spectrometric analysis enable potential researchers to design the necessary sampling and sample preparation program suitable to the objectives of their study. Finally, the results of calibration tests using Ca and K salts and glasses, international mineral standards, and in-house mineral standards show that the accuracy and precision obtained at the 40Ar/39Ar laboratory at CPGeo/USP are comparable to results obtained in the most respected laboratories internationally. The extensive calibration and standardization procedures undertaken ensure that the results of analytical studies carried out in our laboratories will gain immediate international credibility, enabling Brazilian students and scientists to conduct forefront research in earth and planetary sciences.A geocronologia de 40Ar/39Ar por aquecimento a laser permite alta precisão e acurácia analítica, tem resolução espacial em escala micrométrica, e fornece um número de dados estatisticamente significantes para o estudo de processos geológicos e planetários. Um recém construído laboratório de 40Ar/39Ar no CPGeo/USP, São Paulo, Brazil, mune a sociedade científica brasileira com uma técnica eficaz aplicável aos estudos geol

  3. Kinetics of Ar isotopes during neutron irradiation: 39Ar loss from minerals as a source of error in 40Ar/39Ar dating

    Hess, J.C.; Lippolt, H.J.

    1986-01-01

    The loss of 39 Ar from minerals in the course of neutron activation for 40 Ar/ 39 Ar dating is studied by directly measuring the loss rates in vacuum-sealed ampoules. Biotite shows 39 Ar losses between 0.1% and 16%. These losses are predominantly due to diffusion processes from K-poor alteration-phase intergrowths in the biotites at the elevated temperatures during the irradiation. Estimates for the irradiation temperatures range from 150 0 to 180 0 C. Direct 39 Ar recoil loss from biotite seems to be minor compared to difussion loss of recoil-implanted 39 Ar. Precise 40 Ar/ 39 Ar dating of biotites therefore requires the measurement of the 39 Ar losses during irradiation. Glauconite loses not only neutron-induced Ar isotopes ( 39 Ar: 20-22%, 37 Ar: 17-19%) but also radiogenic 40 Ar(∼9%). Slight 39 Ar losses are also observed for light micas (0.2% and 0.35%), hornblendes (0.1%) and sanidines (200 and 700 ppm). 25 refs.; 4 figs.; 6 tabs

  4. Influence of residual Ar+ in Ar cluster ion beam for DLC film formation

    Kitagawa, Teruyuki; Miyauchi, Kazuya; Toyoda, Noriaki; Kanda, Kazuhiro; Ikeda, Tokumi; Tsubakino, Harushige; Matsuo, Jiro; Matsui, Shinji; Yamada, Isao

    2003-01-01

    In order to study the influences of residual Ar monomer ion (Ar + ) on sp 2 content and hardness of diamond like carbon (DLC) films formed by Ar cluster ion beam assisted deposition, Ar cluster ion, Ar + and their mixed ions (Ar cluster ion and Ar + ) bombardments were performed during evaporation of C 60 . From near edge X-ray absorption fine structure (NEXAFS) and Raman spectroscopy measurements, lower sp 2 content in the carbon films was obtained with Ar cluster ion bombardment than that with Ar + and mixed ion. Furthermore higher hardness and smooth surface were shown with Ar cluster ion bombardments. Therefore it was important to reduce Ar + in Ar cluster ion beams to obtain hard DLC films with flat surface

  5. Integral test of KERMA data for SS304 stainless steel in the D-T fusion neutron environment

    Ikeda, Y.; Kosako, K.; Konno, C.

    1994-01-01

    The KERMA (Kinetic Energy Release Material) data play the fundamental role for estimating nuclear heating in the structural components of fusion reactors. The data are produced from the large body of nuclear data relevant to reaction channels associated with the kinetic energy release. Both contributions by neutron and gamma-ray should be addressed to arrived at the final heating products. Extensive efforts have been devoted to the neutron and γ-ray transport profile in many materials, resulting in the validation of cross section data. However, the experimental verification of KERMA data, which is a highly integrated product of neutron and γ-ray, has been limited from the lack of available experimental data. Through the JAERI/USDOE collaborative program on fusion neutronics, novel experimental technique for the direct nuclear heating due to 14 MeV neutrons has been developed based on a micro calorimetric system. The technique demonstrated excellent capability for detecting the temperature rise due to nuclear heating and pertinent verification for the calculation data and methods. This paper deals with the most recent experimental endeavor for the direct nuclear heating measurement in SS-304 stainless steel assembly, where appreciably large amounts of slow neutron and associated secondary γ-rays dominated the field. The nuclear heating up to 200 mm depth in the SS-304 assembly were derived from detected temperature rise employing large SS-304 block type probe materials

  6. Computational analysis of 'dose/collision kerma' relationship and lateral boundary in stereotactic circular fields using EGSNRC

    Leao Junior, Reginaldo G.; Oliveira, Arno H. de; Mourao, Arnaldo P. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departmento de Engenharia Nuclear; Sousa, Romulo V. de [Sao Joao de Deus Hospital, Divinopolis, MG (Brazil); Silva, Hugo L.L. [Santa Casa Hospital, Belo Horizonte, MG (Brazil)

    2016-07-01

    Objectives: This work aimed to obtain data from small fields of X-rays that evidence of the hypotheses cited as cause of difficulties for the dosimetry of these. For this purpose, the verification of compatibility between the dosimetric boundary of field and the geometric size of field, was performed. Also, the verification of kerma dose according to the expected relationship for conventional fields was made. Materials and Methods: Computer simulations of smaller fields 5 x 5 cm² were performed, using the Monte Carlo method by egs{sub c}hamber application, this derived from EGSnrc radiation transport code. As particulate sources were used phase space files of a Clinac 2100 head model coupled to cones Stereotactic Radiosurgery. Results: The simulations suggested the existence of a plateau in discrepancies between the dose FWHM and the nominal diameter of the field close to 8%. These simulations also indicated a decrease of these values for fields with diameters smaller than 12 mm and larger than 36 mm. Simultaneously, the dose kerma differences in depth reached values higher than 14% in the case where the phenomenon is more significant. Conclusion: The data showed that in fact the behavior of small fields clashes with that expected for conventional fields, and that the traditional dosimetric conventions do not apply to such fields requiring a specialized approach to the techniques that employ them. Furthermore, the existence of the aforementioned plateau of discrepancies, along with the decrease thereof in less than 15 mm diameter fields constitute a remarkable finding. (author)

  7. Qualidade do ar interno em ambientes climatizados – verificação dos parâmetros físicos e concentração de dióxido de carbono em agência bancária

    Waldir Nagel Schirmer

    2009-01-01

    Full Text Available A presença de poluentes químicos e biológicos no ar interno de estabelecimentos públicos cria condições que podem comprometera saúde e produtividade dos funcionários. Assim, estes estabelecimentos necessitam de sistemas de climatização bem projetados,que forneçam taxas de ventilação adequadas para garantir o conforto e bem-estar de seus ocupantes, bem como a assepsia dosambientes. O objetivo deste trabalho foi avaliar a qualidade do ar interno (QAI de um banco da região centro-sul do Paraná,através da verificação dos parâmetros físicos de conforto (temperatura, umidade relativa e velocidade do ar e das concentraçõesde dióxido de carbono, seguindo-se a metodologia recomendada pela Resolução n° 09 da Agência Nacional de VigilânciaSanitária (ANVISA. Os resultados obtidos permitiram afirmar que a QAI dos ambientes estudados está comprometida, já quealguns dos parâmetros avaliados apresentaram valores superiores aos recomendados pela referida norma. As altas concentraçõesde CO2 obtidas nestes ambientes podem ser justificadas pela falta de renovação de ar, uma vez que, os aparelhos de climatizaçãodestes ambientes são desprovidos desta função. Sugere-se que, para que se verifiquem melhorias na QAI, efetuem-se mudançasnos sistemas de climatização, fazendo-se uso daqueles projetados especialmente para tais tipos de ambientes e que contemplem arenovação do ar a taxas aceitáveis pela legislação vigente.Abstract The presence of chemical and biologicalpollutants in the indoor air of public buildings creates conditions that may prejudice the health and productivity ofemployees. Thus, these places need air conditioning welldesigned, to provide adequate ventilation rates to ensure thecomfort of its occupants and the aseptic of environments.The objective of this study was to evaluate the indoor airquality (IAQ in a bank located in south-central region ofParana state, Brazil, by checking the physical parameters

  8. Comparison BIPM.RI(I)-K8 of high dose-rate Ir-192 brachytherapy standards for reference air kerma rate of the PTB and the BIPM

    Kessler, C.; Allisy-Roberts, P.J.; Selbach, H.J.

    2015-01-01

    An indirect comparison of the standards for reference air kerma rate (RAKR) for 192 Ir high dose rate (HDR) brachytherapy sources of the Physikalisch-Technische Bundesanstalt (PTB), Germany, and of the Bureau International des Poids et Mesures (BIPM) was carried out at the PTB in September 2011. The comparison result, based on the calibration coefficients for a transfer standard and expressed as a ratio of the PTB and the BIPM standards for reference air kerma rate, is 1.0003 with a combined standard uncertainty of 0.0099. (authors)

  9. Qualidade de maçãs ‘Gala’ armazenadas em atmosfera controlada dinâmica e estática com renovação do ar Quality of ‘Gala’ apples stored in dynamic and static controlled atmosphere with air renovation

    Auri Brackmann

    2005-04-01

    Full Text Available Este experimento teve como objetivo avaliar o efeito da remoção periódica da atmosfera das câmaras de atmosfera controlada com ar e nova instalação, bem como o uso da atmosfera dinâmica, sobre a manutenção da qualidade da maçã 'Gala'. Os tratamentos utilizados foram: (1 controle (sem renovação; (2 renovação da atmosfera diariamente durante o resfriamento dos frutos; (3 renovação da atmosfera diariamente durante o resfriamento e mensalmente no período de armazenamento em atmosfera controlada; (4 renovação da atmosfera mensalmente; (5 50µL L-1 de etileno no interior da câmara; e (6 atmosfera dinâmica (injeção diária de N2 para remoção do CO2. Após oito meses de armazenamento, o tratamento com renovação da atmosfera diariamente durante o resfriamento e mensalmente no período de armazenamento em atmosfera controlada proporcionou frutos com maior firmeza de polpa. Nenhuma das técnicas avaliadas permitiu manter os níveis de etileno nas câmaras de armazenamento abaixo de 5µL L-1. Provavelmente, a absorção do etileno proporciona um benefício igual ou maior com um menor custo, pois a renovação da atmosfera implica altos custos na aquisição de nitrogênio.This experiment was carried out aiming to evaluate the effect of periodical removal of the atmosphere of controlled atmosphere chambers with fresh air and the use of dynamic atmosphere on quality of 'Gala' apples. Evaluated treatments were: (1 control (without air renovation; (2 daily atmosphere renovation during fruit cooling; (3 daily atmosphere renovation during cooling and monthly during controlled atmosphere storage of fruits; (4 monthly atmosphere renovation; (5 50µL L-1 ethylene inside chamber; and (6 dynamic atmosphere (N2 injection to remove CO2. After eight months of storage, daily atmosphere renovation during cooling and monthly during controlled atmosphere storage maintained fruit firmness. None of the evaluated techniques allowed ethylene levels

  10. Psicologia feminista em Portugal : dificuldades e conquistas

    Saavedra, Luísa

    2010-01-01

    Pretende-se, com este artigo, fazer um balanço do que tem sido a Psicologia Feminista em Portugal. Tendo em conta que cada ciência comporta evoluções e posições epistemológicas e metodológicas distintas, começar-se-á por traçar em linhas gerais alguns marcos da psicologia no que diz respeito à forma de abordar as questões das mulheres e homens e definindo o que se entende por psicologia feminista. Seguidamente, serão evidenciados alguns aspectos políticos e sociais que condicionaram o desenvo...

  11. Importance of the neutrons kerma coefficient in the planning of Brachytherapy treatments with Cf-252 sources; Importancia del coeficiente de kerma de neutrones en la planeacion de tratamientos de Braquiterapia con fuentes de Cf-252

    Paredes G, L.; Balcazar G, M. [ININ, 52045 Ocoyocac, Estado de Mexico (Mexico); Azorin N, J. [Universidad Autonoma Metropolitana, 09000 Mexico D.F. (Mexico); Francois L, J.L. [UNAM, 04500 Mexico D.F. (Mexico)]. e-mail: lpg@nuclear.inin.mx

    2006-07-01

    The Cf-252 is a fast neutrons emitting radioisotope by spontaneous fission that can be used as sealed source in medicine applications, industry and research. Commercially its offer sources of different sizes, compact and with a fast neutrons emission of the order of 10{sup 6} n/s-{mu}g and an energy spectra that presents respectively maxim and average energy in 2.1 MeV and 0.7 MeV. In medicine new applications are being developed for the treatment of patient with hypoxic and voluminous tumors, where the therapy with photons has not given positive results, as well as for the protocols of therapy treatment by boron neutron capture, where very small sources of Cf-252 will be used with the interstitial brachytherapy technique of high and low dose rate. In this work an analysis of how the small differences that exist in the elementary composition of 4 wicked tumors, 4 ICRU healthy tissues and 3 substitute materials of ICRU tissue used in dosimetry are presented, its generate changes in the neutrons kerma coefficient in function of the energy and consequently in the absorbed dose in the interval of 11 eV to 29 MeV. These differences can produce maximum variations of the neutron kerma coefficients ratio for E{sub n} > 1 keV of the one: 15% tumor/ICRU guest healthy tissue, 12% ICRU tumor/muscle, 12% ICRU healthy tissues ICRU/ICRU muscle, 22% substitutes tissue/tumor and 22% ICRU substitutes tissue/muscle. Also, it was found that the average value of the neutrons kerma coefficient for the 4 wicked tumors is from 6% to 7% smaller that the average value for the soft tissue in the interval energy of interest for therapy with fast neutrons with E{sub n} > 1 MeV. These results have a special importance during the planning process of brachytherapy treatments with sources of {sup 252}Cf, to optimize and to individualize the patients treatments. (Author)

  12. 40Ar-39Ar stepheating studies of clay concentrates from Irish orebodies

    Halliday, A.N.

    1978-01-01

    40 Ar- 39 Ar step heating analyses of clay concentrates from the Gortdrum and Tynagh orebodies (Ireland) previously dated by conventional K-Ar, indicate major losses of 39 Ar (32 to 45%) and rad. 40 Ar (25 to 35%) during the irradiation. The proportion of rad. 40 Ar loss, unlike that of 39 Ar, increases with J-value. The difference between 39 Ar and rad. 40 Ar proportion losses is related to the mineralogy and grain intimacy. These also affect the stepwise release patterns - the Gortdrum concentrates yield age spectra very consistent with 39 Ar recoil predictions, whereas the Tynagh concentrates in which the grains are intimately intergrown, show no clear evidence for 39 Ar recoil depletion in the K-rich phases. The difference is resolvable if illite argon release is not a simple volume diffusion type process under vacuum conditions. (author)

  13. HDR-Aggregate Read Service (ARS)

    Department of Veterans Affairs — ARS is a SOAP web service exposed over HTTPS that provides an aggregated (report) view of HTH Survey, DMP and Census data stored in the HDR DB. ARS is deployed in...

  14. Air-kerma strength determination of a new directional 103Pd source

    Aima, Manik; Reed, Joshua L.; DeWerd, Larry A.; Culberson, Wesley S.

    2015-01-01

    Purpose: A new directional 103 Pd planar source array called a CivaSheet™ has been developed by CivaTech Oncology, Inc., for potential use in low-dose-rate (LDR) brachytherapy treatments. The array consists of multiple individual polymer capsules called CivaDots, containing 103 Pd and a gold shield that attenuates the radiation on one side, thus defining a hot and cold side. This novel source requires new methods to establish a source strength metric. The presence of gold material in such close proximity to the active 103 Pd region causes the source spectrum to be significantly different than the energy spectra of seeds normally used in LDR brachytherapy treatments. In this investigation, the authors perform air-kerma strength (S K ) measurements, develop new correction factors for these measurements based on an experimentally verified energy spectrum, and test the robustness of transferring S K to a well-type ionization chamber. Methods: S K measurements were performed with the variable-aperture free-air chamber (VAFAC) at the University of Wisconsin Medical Radiation Research Center. Subsequent measurements were then performed in a well-type ionization chamber. To realize the quantity S K from a directional source with gold material present, new methods and correction factors were considered. Updated correction factors were calculated using the MCNP 6 Monte Carlo code in order to determine S K with the presence of gold fluorescent energy lines. In addition to S K measurements, a low-energy high-purity germanium (HPGe) detector was used to experimentally verify the calculated spectrum, a sodium iodide (NaI) scintillating counter was used to verify the azimuthal and polar anisotropy, and a well-type ionization chamber was used to test the feasibility of disseminating S K values for a directional source within a cylindrically symmetric measurement volume. Results: The UW VAFAC was successfully used to measure the S K of four CivaDots with reproducibilities within

  15. Air-kerma strength determination of a new directional {sup 103}Pd source

    Aima, Manik, E-mail: aima@wisc.edu; Reed, Joshua L.; DeWerd, Larry A.; Culberson, Wesley S. [Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin 53705 (United States)

    2015-12-15

    Purpose: A new directional {sup 103}Pd planar source array called a CivaSheet™ has been developed by CivaTech Oncology, Inc., for potential use in low-dose-rate (LDR) brachytherapy treatments. The array consists of multiple individual polymer capsules called CivaDots, containing {sup 103}Pd and a gold shield that attenuates the radiation on one side, thus defining a hot and cold side. This novel source requires new methods to establish a source strength metric. The presence of gold material in such close proximity to the active {sup 103}Pd region causes the source spectrum to be significantly different than the energy spectra of seeds normally used in LDR brachytherapy treatments. In this investigation, the authors perform air-kerma strength (S{sub K}) measurements, develop new correction factors for these measurements based on an experimentally verified energy spectrum, and test the robustness of transferring S{sub K} to a well-type ionization chamber. Methods: S{sub K} measurements were performed with the variable-aperture free-air chamber (VAFAC) at the University of Wisconsin Medical Radiation Research Center. Subsequent measurements were then performed in a well-type ionization chamber. To realize the quantity S{sub K} from a directional source with gold material present, new methods and correction factors were considered. Updated correction factors were calculated using the MCNP 6 Monte Carlo code in order to determine S{sub K} with the presence of gold fluorescent energy lines. In addition to S{sub K} measurements, a low-energy high-purity germanium (HPGe) detector was used to experimentally verify the calculated spectrum, a sodium iodide (NaI) scintillating counter was used to verify the azimuthal and polar anisotropy, and a well-type ionization chamber was used to test the feasibility of disseminating S{sub K} values for a directional source within a cylindrically symmetric measurement volume. Results: The UW VAFAC was successfully used to measure the S

  16. $\\beta$ decay of $^{47}$Ar

    Weissman, L; Bergmann, U C; Brown, B A; Catherall, R; Cederkäll, J; Dillmann, I; Hallmann, O; Fraile-Prieto, L M; Franchoo, S; Gaudefroy, L; Köster, U; Kratz, K L; Pfeiffer, B; Sorlin, O; 10.1103/PhysRevC.70.024304

    2004-01-01

    Information on beta -decay properties of neutron-rich /sup 47/Ar was obtained at the ISOLDE facility at CERN using isobaric selectivity. This was achieved by a combination of a plasma-ion source with a cooled transfer line and subsequent mass separation. A doubly charged beam was used in order to improve the signal-to-background ratio associated with multi-charged noble gas fission products. The identification of the /sup 47/Ar gamma -ray transitions was performed by comparing the spectra obtained from direct proton bombardment of the target and of the neutron converter. New excited levels in the daughter /sup 47/K nucleus corresponding to the negative-parity states were observed. The obtained data are compared to the result of large-scale shell model calculations and quasiparticle random-phase approximation predictions. (29 refs).

  17. ARS - Helsinki - 2006 / Galina Balashova

    Balashova, Galina

    2006-01-01

    Steven Holli projekteeritud Kiasma muuseumihoonest Helsingis. Kontseptuaalkunsti näitusest ARS 06 "Reaalsustunne" Kiasmas. Eestlastest esineb Mark Raidpere. Vene kunstnikegrupi AEC+F ja vene kunstnike Juri Vassiljevi ning Aleksandr Ponomarjovi töödest näitusel. Ka Gerda Steineri & Jörg Lenzlingeri (Šveits), Martin & Munoz'i (USA, Hispaania), arvutigraafik Charles Sandisoni (SB), videokunstnik Bill Viola (USA) jt. töödest

  18. Photoionization study of HgAr

    Linn, S.H.; Brom, J.M. Jr.; Tzeng, W.; Ng, C.Y.

    1985-01-01

    Photoionization efficiency data for HgAr + have been obtained in the region of 680--1240 A. The ionization energy of HgAr was determined to be 10.217 +- 0.012 eV. This value allows the calculation of the dissociation energy of HgAr + to be 0.228 +- 0.017 eV. The relative probabilities for the formation of HgAr + via the reactions Ar* x Hg or Hg* x Ar→ HgAr + +e - with Ar* and Hg* prepared in high Rydberg states in the energy range of 10.22--15.79 eV were estimated. Although the radii for the 3d and 5s Rydberg ortitals of Ar have similar values, the probabilities for the formation of HgAr + from Hg x Ar* with Ar* in the 5s[3/2] 0 1 and 5s'[1/2] 0 1 Rydberg states are substantially greater than those when the Ar* excited atoms are in the 3d[1/2] 0 1 , 3s[3/2] 0 1 , and 3d'[3/2] 0 1 Rydberg levels. The ratio for the cross sections for the formation of HgAr + from Hg x Ar* with Ar* formed in the 3d[1/2] 0 1 and 4d[1/2] 0 1 states, as well as that with Ar* prepared in the 5d[1/2] 0 1 and 6d[1/2] 0 1 states, were found to be consistent with the predictions of the previous impact parameter calculations

  19. Construction of a laboratory for the implantation of primary standardization of the magnitude kerma in the air for the X-ray beams used in mammography

    Cardozo, W.L.; Magalhes, L.A.A.M.F.; Peixoto, J.G.P.

    2009-01-01

    Aiming to diminish the uncertainty in each phase of the metrological chain, and the uncertainty in dosimetry processed at the X-ray beam applied in the mammography, is necessary that the LNMRI/IRD to develop a reference primary standard for the absolute form to the magnitude kerma in the air

  20. Comparison BIPM.RI(I)-K8 of high dose-rate Ir-192 brachytherapy standards for reference air kerma rate of the VSL and the BIPM

    Alvarez, J.T.; De Pooter, J.A.; Andersen, Claus E.

    2014-01-01

    An indirect comparison of the standards for reference air kerma rate for 192Ir high dose rate brachytherapy sources of the Dutch Metrology Institute (VSL), The Netherlands, and of the Bureau International des Poids et Mesures (BIPM) was carried out at the VSL in November 2009. The comparison resu...

  1. Comparison of the air-kerma standards of the BEV and the BIPM in the low-energy X-ray range

    Burns, D.T.; Witzani, J.

    2002-09-01

    A direct comparison has been made between the air-kerma standards of the BEV and the BIPM in the low-energy x-ray range. The results at the different radiation qualities show the standards to be in reasonable agreement with respect to the combined relative standard uncertainty of the comparison of 2.4 x 10 -3 . (authors)

  2. Comparison of the air-kerma standards of the VNIIM and the BIPM in the medium-energy X-ray range

    Burns, D.T.; Villevalde, N.D.; Oborin, A.V.; Yurjatin, E.N.

    2001-09-01

    An indirect comparison has been made between the air-kerma standards of the VNIIM and the BIPM in the medium-energy x-ray range. The results show the standards to be in agreement within the stated uncertainty. (authors)

  3. Measurement of air kerma rates for 6- to 7-MeV high-energy gamma-ray field by ionisation chamber and build-up plate.

    Kowatari, Munehiko; Tanimura, Yoshihiko; Tsutsumi, Masahiro

    2014-12-01

    The 6- to 7-MeV high-energy gamma-ray calibration field by the (19)F(p, αγ)(16)O reaction is to be served at the Japan Atomic Energy Agency. For the determination of air kerma rates using an ionisation chamber in the 6- to 7-MeV high-energy gamma-ray field, the establishment of the charged particle equilibrium must be achieved during measurement. In addition to measurement of air kerma rates by the ionisation chamber with a thick build-up cap, measurement using the ionisation chamber and a build-up plate (BUP) was attempted, in order to directly determine air kerma rates under the condition of regular calibration for ordinary survey meters and personal dosemeters. Before measurements, Monte Carlo calculations were made to find the optimum arrangement of BUP in front of the ionisation chamber so that the charged particle equilibrium could be well established. Measured results imply that air kerma rates for the 6- to 7-MeV high-energy gamma-ray field could be directly determined under the appropriate condition using an ionisation chamber coupled with build-up materials. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Re-establishment of the air kerma and ambient dose equivalent standards for the BIPM protection-level 60Co beam

    Kessler, C.; Roger, P.

    2005-07-01

    The air kerma and ambient dose equivalent standards for the protection-level 60 Co beam have been re-established following the repositioning of the irradiator and modifications to the beam. Details concerning the standards and the new uncertainty budgets are described in this report with their implications for dosimetry comparisons and calibrations. (authors)

  5. Exigências nutricionais da grápia ao fósforo e enxofre em Argissolo Vermelho distrófico arênico: efeito da adubação no crescimento Nutritional demand of grápia to phophorus and sulfur in paleaudalf soil: fertilization effects on growth

    Evandro Luiz Missio

    2004-08-01

    Full Text Available A grápia (Apuleia leiocarpa Vog. Macbride é uma espécie de grande interesse madeireiro, encontrando-se, atualmente, bastante dizimada devido à exploração extrativista, sem haver reposição através de reflorestamento. O objetivo deste trabalho foi determinar os níveis ótimos de adubação de fósforo e enxofre no crescimento de plantas jovens de grápia. As plantas foram cultivadas em vasos contendo 3,5kg de solo Argissolo Vermelho distrófico arênico, sob condições de casa de vegetação não climatizada. O delineamento experimental foi o inteiramente casualizado com seis repetições. Foram avaliados 16 tratamentos em esquema bifatorial completo (4x4, representados pela combinação de quatro doses de P (0, 60, 120 e 180mg kg-1 e quatro de enxofre (0, 10, 20 e 30mg kg-1. A análise do crescimento das plantas foi realizada mensalmente através da altura da planta, diâmetro do caule e número de folhas remanescentes. Aos 130 dias após a emergência das plantas, avaliaram-se ainda o número de folhas caídas, matéria seca das folhas, caule, raízes e total da planta e a relação entre a matéria seca das raízes e da parte aérea. A produção de matéria seca total das plantas jovens de grápia respondeu positivamente à adubação conjunta de P e S, com dose de máxima eficiência técnica estimada de, respectivamente, 204 e 16mg kg-1 de solo. A adubação fosfatada na dose igual ou acima de 120mg kg-1 de solo induziu o aparecimento de clorose foliar típica da deficiência de Fe. A alta disponibilidade de P no solo favoreceu o crescimento da parte aérea em detrimento das raízes.Grápia (Apuleia leiocarpa Vog. Macbride is an important native forest species that has been in extinction process. The aim of this study was to determine the optimum levels of phosphorus and sulfur fertilization on the initial growth of grápia. Grápia plants were cultivated in pots containing 3.5kg of a Paleudalf soil, under unclimatized glasshouse

  6. Calculation of the uncertainty associated to the result of entrance surface air kerma for conventional radiology patients

    Blanco, D.; Mora, P.; Khoury, H.; Fabri, D.; Leyton, F.; Cardenas, J.; Blanco, S.; Kodlulovich, S.; Roas, N.; Benavente, T.; Ortiz Lopez, P.; Ramirez, R.

    2008-01-01

    Radiation doses from diagnostic radiology are the largest contribution to the collective dose and the use of guidance (reference levels) has proven to be a tool for optimization of protection. Recently, with the support of the International Atomic Energy Agency (IAEA), eight countries of the Latin-American region have been working together on a programme to test methodologies for determining preliminary values of guidance levels for X-ray chest, lumbar spine and breast examinations. The approach used was to obtain entrance surface air kerma from measurements of X-ray tube outputs, corrected for distance and backscatter and later for real exposure parameters used with patients. For quality control, some of these values for a reduced number of patients were compared with direct TLD measurements directly placed on the patient during exposure. Given the number of parameters involved in the two methods, relatively large differences are deemed to be found in the comparison. The only way of deciding if measurements and calculations are outliers, for example, due to a systematic error or a mistake, is to compare these differences with the combined uncertainty. The aim of this paper is to present (in a detailed way) the methodology used in the pilot program ARCAL LXXV, the analyses of data performed within the survey and the estimated uncertainty. The parameters analyzed were: precision of the readings, positioning of the detector, reproducibility of the mAs and kV, long term stability of the instrument, radiation quality, kerma rate, radiation incidence, field size and field homogeneity, calibration factor of the equipment, temperature and pressure measurement, X-ray tube output curve adjustment, backscatter factor and focus-patient distance. The combined standard uncertainty for Ke in chest radiography in adult patients of standard complexion, was 12%, and the expanded uncertainty (k=2) was 24%. (author)

  7. The SFMOMA AR Game Jam

    Brin, Sarah; Gangsei, Erica

    2018-01-01

    In the Summer of 2016, Pokémon Go precipitated a surge of new play experiences in museums. Cultural heritage institutions across disciplines were confronted with the sudden ubiquity of augmented reality (AR). Some museums enthusiastically integrated Pokémon into their programs, while some grapple......, and Rebecca Edwards. “Night at the Museum: The 2016 Getty/USC Game Jam.” Blog. The Getty Iris, March 31, 2016. http://blogs.getty.edu/iris/a-night-at-themuseum-the-2016-gettyusc-game-jam/....

  8. Doses monitoring in radiology: calibration of air kerma-area product (P{sub KA}) meters; Monitoracao de doses em radiologia: a calibracao de medidores do produto kerma-area (P{sub KA})

    Terini, Ricardo Andrade; Campelo, Maria Carolina de Santana; Almeida Junior, Jose Neres de, E-mail: rterini@pucsp.br [Pontificia Universidade Catolica de Sao Paulo (PUC-SP), SP (Brazil); Herdade, Silvio Bruni; Pereira, Marco Aurelio Guedes [Universidade de Sao Paulo (IEE/USP), SP (Brazil). Instituto de Energia e Ambiente

    2013-11-15

    Materials and methods: different qualities of both incident and transmitted beams were utilized in conditions similar to a clinical setting, analyzing the influence from the reference dosimeter, from the distance between meters, from the filtration and from the average beam energy. Calibrations were performed directly against a standard 30 cm{sup 3} cylindrical chamber or a parallel-plate monitor chamber, and indirectly against the PDC meter. Results: the lowest energy dependence was observed for transmitted beams. The cross calibration between the Diamentor E2 and the PDC meters, and the PDC presented the greatest propagation of uncertainties. Conclusion: the calibration coefficient of the PDC meter showed to be more stable with voltage, while the Diamentor E2 calibration coefficient was more variable. On the other hand, the PDC meter presented greater uncertainty in readings (5.0%) than with the use of the monitor chamber (3.5%) as a reference. (author)

  9. Differences among KERMA or DPA data calculated from JENDL-4.0, ENDF/B-VII.1, JEFF-3.2 and FENDL-3.1b with NJOY

    Konno, C.

    2016-01-01

    KERMA factors and DPA cross-section data below 20 MeV in the official ACE files of JENDL-4.0, ENDF/B-VII.1, JEFF-3.2 and FENDL-3.1b were compared in detail. As a result, it was found out that the KERMA and DPA data of a lot of nuclei were different among the nuclear data libraries. Reasons of most of the differences were successfully categorized to the nuclear data and NJOY issues. The KERMA factors and DPA cross-section data in the ACE files with the problems should be revised. (author)

  10. The effects of retrograde reactions and of diffusion on 39Ar-40Ar ages of micas

    Allaz, Julien; Engi, Martin; Berger, Alfons

    2011-01-01

    Effects of metamorphic reactions occurring during decompression were explored to understand their influence on 39Ar-40Ar ages of micas. Monometamorphic metasediments from the Lepontine Alps (Switzerland) were studied. Collected samples reached lower amphibolite facies during the Barrovian....... XRD-data indicated that some mineral separates prepared for Ar-Ar stepwise heating analysis were monomineralic, whereas others were composed of two white micas (muscovite with paragonite or margarite), or biotite and chlorite. In monomineralic samples 37Ar/39Ar and 38Ar/39Ar (proportional to Ca....../K and Cl/K ratios) did not change and the resulting ages can be interpreted unambiguously. In mineral separates containing two white micas, Ca/K and Cl/K ratios were variable, reflecting non-simultaneous laboratory degassing of the two heterochemical Ar-reservoirs. These ratios were used to identify each...

  11. European inter-comparison of Monte Carlo codes users for the uncertainty calculation of the kerma in air beside a caesium-137 source; Intercomparaison europeenne d'utilisateurs de codes monte carlo pour le calcul d'incertitudes sur le kerma dans l'air aupres d'une source de cesium-137

    De Carlan, L.; Bordy, J.M.; Gouriou, J. [CEA Saclay, LIST, Laboratoire National Henri Becquerel, Laboratoire de Metrologie de la Dose 91 - Gif-sur-Yvette (France)

    2010-07-01

    Within the frame of the CONRAD European project (Coordination Network for Radiation Dosimetry), and more precisely within a work group paying attention to uncertainty assessment in computational dosimetry and aiming at comparing different approaches, the authors report the simulation of an irradiator containing a caesium 137 source to calculate the kerma in air as well as its uncertainty due to different parameters. They present the problem geometry, recall the studied issues (kerma uncertainty, influence of capsule source, influence of the collimator, influence of the air volume surrounding the source). They indicate the codes which have been used (MNCP, Fluka, Penelope, etc.) and discuss the obtained results for the first issue

  12. 40Ar/39Ar dating of the Late Cretaceous

    Gaylor, Jonathan

    2013-01-01

    As part of the wider European GTS Next project, I propose new constraints on the ages of the Late Cretaceous, derived from a multitude of geochronological techniques, and successful stratigraphic interpretations from Canada and Japan. In the Western Canada Sedimentary Basin, we propose a new constraint on the age of the K/Pg boundary in the Red Deer River section (Alberta, Canada). We were able to cyclo-stratigraphically tune sediments in a non-marine, fluvial environment utilising high-resolution proxy records suggesting a 11-12 precession related cyclicity. Assuming the 40 Ar/ 39 Ar method is inter-calibrated with the cyclo-stratigraphy, the apparent age for C29r suggests that the K/Pg boundary falls between eccentricity maxima and minima, yielding an age of the C29r between 65.89 ± 0.08 and 66.30 ± 0.08 Ma. Assuming that the bundle containing the coal horizon represents a precession cycle, the K/Pg boundary is within the analytical uncertainty of the youngest zircon population achieving a revised age for the K/Pg boundary as 65.75 ± 0.06 Ma. The Campanian - Maastrichtian boundary is preserved in the sedimentary succession of the Horseshoe Canyon Formation and has been placed 8 m below Coal nr. 10. Cyclo-stratigraphic studies show that the formation of these depositional sequences (alternations) of all scales are influenced directly by sea-level changes due to precession but more dominated by eccentricity cycles proved in the cyclo-stratigraphic framework and is mainly controlled by sand horizons, which have been related by auto-cyclicity in a dynamic sedimentary setting. Our work shows that the Campanian - Maastrichtian boundary in the Western Canada Sedimentary Basin coincides with 2.5 eccentricity cycles above the youngest zircon age population at the bottom of the section and 4.9 Myr before the Cretaceous - Palaeogene boundary (K/Pg), and thus corresponds to an absolute age of 70.65 ± 0.09 Ma producing an 1.4 Myr younger age than recent published ages

  13. A melancolia em Al Berto

    Camila Emanuele Martins de Souza

    2015-01-01

    Este trabalho objetiva estudar, sob a perspectiva da melancolia, os livros Salsugem (1984) e Horto de Incêndio (1997), de Al Berto. O autor português produz escritos em que a temática da melancolia atravessa a palavra, o que justifica o debruçar-se sobre as construções textuais da poética albertiana, a fim de traçar-lhe novas possibilidades de leitura por esse ângulo. Para isso, com o intuito de compreender o discurso melancólico segue-se o embasamento teórico: de Klibansky, Panosfsky e Saxl ...

  14. Triaxial superdeformation in 40Ar

    Taniguchi, Yasutaka; Ikeda, Kiyomi; Kanada-En'yo, Yoshiko; Kimura, Masaaki; Horiuchi, Hisashi; Ideguchi, Eiji

    2010-01-01

    Superdeformed (SD) states in 40 Ar have been studied using the deformed-basis antisymmetrized molecular dynamics. Low-energy states were calculated by the parity and angular momentum projection and the generator coordinate method (GCM). Basis wave functions were obtained by the energy variation with a constraint on the quadrupole deformation parameter β, while other quantities such as triaxiality γ were optimized by the energy variation. By the GCM calculation, an SD band was obtained just above the ground-state band. The SD band involves a K π =2 + side band due to the triaxiality. The calculated electric quadrupole transition strengths of the SD band reproduce the experimental values appropriately. Triaxiality is significant for understanding low-lying states.

  15. arXiv Probing Leptogenesis

    Chun, E.J.; Dev, P.S.B.; Drewes, M.; Fong, C.S.; Garbrecht, B.; Hambye, T.; Harz, J.; Hernández, P.; Kim, C.S.; Molinaro, E.; Nardi, E.; Racker, J.; Rius, N.; Zamora-Saa, J.

    2018-02-28

    The focus of this chapter lies on the possible experimental tests of leptogenesis scenarios. We consider both leptogenesis generated from oscillations, as well as leptogenesis from out-of-equilibrium decays. As the Akhmedov-Rubakov-Smirnov (ARS) mechanism allows for heavy neutrinos in the GeV range, this opens up a plethora of possible experimental tests, e.g. at neutrino oscillation experiments, neutrinoless double beta decay, and direct searches for neutral heavy leptons at future facilities. In contrast, testing leptogenesis from out-of-equilibrium decays is a quite difficult task. We comment on the necessary conditions for having successful leptogenesis at the TeV-scale. We further discuss possible realizations and their model specific testability in extended seesaw models, models with extended gauge sectors, and supersymmetric leptogenesis. Not being able to test high-scale leptogenesis directly, we present a way to falsify such scenarios by focusing on their washout processes. This is discussed specific...

  16. Dating method with /sup 39/Ar

    Loosli, H H [Bern Univ. (Switzerland). Physikalisches Inst.

    1983-04-01

    The principles of a dating method based on the cosmic-ray-produced radioisotope /sup 39/Ar are given. Technical requirements such as background and standard gas samples and gas proportional counting systems are described. With samples extracted from Greenland ice it can be demonstrated that /sup 39/Ar ages agree with ages obtained by other methods. First results on ocean water samples show that with this isotope valuable information on ocean mixing and circulation can be expected. /sup 39/Ar results on groundwater samples disagree for some aquifers with conventional /sup 14/C ages; possible explanations are discussed, especially underground production of /sup 39/Ar.

  17. GPS-Based AR Games Development Potential

    Gregorius Alvin Raditya Santoso

    2014-11-01

    Full Text Available The application of new technologies in a game is not a new thing. One example is the application of Augmented Reality (AR technology in game. Many people do not know the application of AR technology in game, although the application of this technology is able to produce a game with unique gameplay. In addition, since AR game is GPS-based, it offers new gaming experience, that is, playing outdoors in which the real world becomes the game arena. This advantage gives the AR technology a huge potential to be developed into a game

  18. Avaliação da exposição ocupacional em procedimentos de hemodinâmica Evaluation of occupational exposure in hemodynamic procedures

    Silvia C. Gusso Scremin

    2006-04-01

    Full Text Available OBJETIVO: Avaliar a dose efetiva recebida pelos trabalhadores envolvidos na realização de procedimentos de hemodinâmica, de forma a estabelecer parâmetros comparativos entre os dados obtidos com uma câmara de ionização e pelos dosímetros usados para monitoração individual. MATERIAIS E MÉTODOS: A avaliação foi desenvolvida em um serviço de hemodinâmica, sendo que os testes constaram da medida do taxa de kerma no ar no ambiente real de trabalho, na posição ocupada por médicos e enfermeiros, com e sem a utilização de barreira plumbífera de proteção. Foi levado em consideração o número de exames realizados no serviço e foram selecionados as projeções e parâmetros radiográficos mais utilizados. Para a estimativa da dose efetiva foram utilizados fatores de conversão encontrados na literatura. RESULTADOS: Os valores encontrados em dose efetiva e de dosimetria são consistentes. Observou-se, ainda, que o uso da barreira protetora plumbífera reduz em até 97% a dose recebida pelo profissional, devendo esta ser utilizada na rotina de exames. CONCLUSÃO: Os valores apresentados são representativos, não podendo ser assumidos como reprodução das condições de monitoração individual, mas são válidos para comparações e orientação na otimização das doses.OBJECTIVE: This study aims to evaluate the effective ionizing radiation dose received by staff involved in interventional vascular procedures to establish parameters for comparison between the data obtained with an ionization chamber and with the dosimeters used for individual monitoring. MATERIALS AND METHODS: The evaluation was performed in a cardiac catheter laboratory and air kerma rate was measured in a real working environment, in the positions occupied by physicians and nurses, with and without the lead glass shield. The number of tests performed in the laboratory was taken into consideration and most common projections and radiographic parameters were

  19. AMIDO RESISTENTE EM FARINHAS DE BANANA VERDE

    Dayana Portes RAMOS

    2010-03-01

    Full Text Available

    Este trabalho teve por objetivo avaliar o teor de amido resistente (AR em farinhas de banana verde produzidas a partir de treze genótipos de bananeira. Para a produção da farinha foram separadas a 1ª, 3ª e 5ª pencas de cada genótipo, na qual cada penca correspondeu a uma repetição. Os frutos de cada penca no estádio 1 (casca completamente verde de maturação foram descascados manualmente, cortados em fatias circulares de 0,5 cm e desidratados em estufa com circulação de ar a 40ºC por 48 horas, sendo em seguida moídos. A análise de AR consistiu em um processo enzimático, calculando-se o conteúdo final pela concentração de glicose liberada. Os resultados foram submetidos à análise estatística e mostraram diferenças significativas para o teor de AR nas farinhas obtidas dos genótipos de bananeira, sendo que a farinha com maior teor de AR foi a produzida a partir do cultivar ‘Nam’ (40,25% e a menor pelo híbrido ‘Fhia 01’ (10,01%. Pode-se concluir que o conteúdo de AR varia em relação ao genótipo utilizado para a confecção da farinha e que a banana pode ser uma boa opção de estudo de alimento funcional.

  20. Estudo comparativo do resfriamento de laranja valência com ar forçado e com água

    Teruel Bárbara

    2003-01-01

    Full Text Available Este trabalho apresenta um estudo para comparar o resfriamento rápido de laranja Valência (Citrus sinensis O., com ar forçado e com água gelada. O sistema de resfriamento rápido com ar forçado operou com um fluxo de ar de 1.933m³/h (3 l/s por kg de produto resfriado, a uma temperatura de 1ºC e UR=88,4 ± 2,0%, com uma velocidade do ar em torno de 1m/s. Nos experimentos com água gelada foi utilizado um sistema de imersão, com uma capacidade de 0,23m³ de água a uma temperatura de aproximadamente 1ºC. Foi determinando o tempo meio e de sete oitavos do resfriamento, partindo das leituras de temperatura, perfazendo-se duas repetições em cada experimento. Os resultados mostraram que, o resfriamento do leito de frutas com ar forçado não é homogêneo, obtendo-se um tempo de sete oitavos do resfriamento que variaram de 107min a 170min, dependendo da posição do fruto no interior da embalagem. Já no sistema com água gelada, o resfriamento acontece uniformemente em todo em todo o leito de frutos, sendo o tempo médio de resfriamento de 57min.

  1. 39Ar/Ar measurements using ultra-low background proportional counters

    Hall, Jeter; Aalseth, Craig E.; Bonicalzi, Ricco M.; Brandenberger, Jill M.; Day, Anthony R.; Humble, Paul H.; Mace, Emily K.; Panisko, Mark E.; Seifert, Allen

    2016-01-01

    Age-dating groundwater and seawater using the 39 Ar/Ar ratio is an important tool to understand water mass-flow rates and mean residence time. Low-background proportional counters developed at Pacific Northwest National Laboratory use mixtures of argon and methane as counting gas. We demonstrate sensitivity to 39 Ar by comparing geological (ancient) argon recovered from a carbon dioxide gas well and commercial argon. The demonstrated sensitivity to the 39 Ar/Ar ratio is sufficient to date water masses as old as 1000 years. - Highlights: • 39 Ar/Ar age dating is important for understanding environmental water migration. • Ultra low background proportional counters have been developed. • 39 Ar is detected in atmospheric argon at a rate of 70.3 counts per day. The demonstrated background is 166 counts per day. • Age dating is possible for water with underground residence time of up to 1000 years.

  2. 40Ar-39Ar method for age estimation: principles, technique and application in orogenic regions

    Dalmejer, R.

    1984-01-01

    A variety of the K-Ar method for age estimation by 40 Ar/ 39 Ar recently developed is described. This method doesn't require direct analysis of potassium, its content is calculated as a function of 39 Ar, which is formed from 39 K under neutron activation. Errors resulted from interactions between potassium and calcium nuclei with neutrons are considered. The attention is paid to the technique of gradual heating, used in 40 Ar- 39 Ar method, and of obtaining age spectrum. Aplicabilities of isochronous diagram is discussed for the case of presence of excessive argon in a sample. Examples of 40 Ar- 39 Ar method application for dating events in orogenic regions are presented

  3. Geology, geochemistry and 40K-40Ar geochronometry of Miocene magmatism in Algiers area, Northern Algeria

    Belanteur, O.; Ouabadi, A.; Semroud, B.; Megartsi, M.H.; Fourcade, S.

    1995-01-01

    Miocene magmatic rocks outcrop within a narrow coastal strip east of Algiers. They include basaltic and andesitic lava flows and intrusions (Dellys, Cap Djinet), the Thenia granodioritic plug and the dacitic to rhyolitic lavas and pyroclastic flows from Zemmouri El Bahri and El Kerma. Despite the effects of hydrothermal alteration, 40 K- 40 Ar ages coupled with micropalaeontological data lead to recognition of two emplacement events at 16-15 and 14-12 Ma, respectively. All the studied calc-alkaline to potassic calc-alkaline rocks are enriched in highly incompatible elements and display negative Nb anomalies. Acid magmas have a pronounced crustal imprint ( 87 Sr 86 Sr i =3D 0.7082 to 0.7155; δ 18 O =3D +9 to +13 per mill) which together with La/Nb ratios argues for the occurrence of upper crustal contamination processes. However, the Nb-depletion of the associated basalts suggest that the studied magmas derive from a mantle source which underwent subduction-related metasomatic enrichments prior to their Miocene emplacement. (authors). 13 refs., 3 figs., 2 tabs

  4. First-principles calibration of 40Ar/39Ar mineral standards and complete extraction of 40Ar* from sanidine

    Morgan, L. E.; Kuiper, K.; Mark, D.; Postma, O.; Villa, I. M.; Wijbrans, J. R.

    2010-12-01

    40Ar/39Ar geochronology relies on comparing argon isotopic data for unknowns to those for knowns. Mineral standards used as neutron fluence monitors must be dated by the K-Ar method (or at least referenced to a mineral of known K-Ar age). The commonly used age of 28.02 ± 0.28 Ma for the Fish Canyon sanidine (FCs) (Renne et al., 1998) is based upon measurements of radiogenic 40Ar in GA1550 biotite (McDougall and Roksandic, 1974), but underlying full data were not published (these measurements were never intended for use as an international standard), so uncertainties are difficult to assess. Recent developments by Kuiper et al. (2008) and Renne et al. (2010) are limited by their reliance on the accuracy of other systems. Modern technology should allow for more precise and accurate calibration of primary K-Ar and 40Ar/39Ar standards. From the ideal gas law, the number of moles of 40Ar in a system can be calculated from measurements of pressure, volume, and temperature. Thus we have designed and are proceeding to build a pipette system to introduce well-determined amounts of 40Ar into noble gas extraction lines and mass spectrometers. This system relies on components with calibrations traceable to SI unit prototypes, including a diaphragm pressure gauge (MKS Instruments), thermocouples, and a “slug” of an accurately determined volume to be inserted into the reservoir for volume determinations of the reservoir and pipette. The system will be renewable, with a lifetime of ca. 1 month for gas in the reservoir, and portable, to permit interlaboratory calibrations. The quantitative extraction of 40Ar* from the mineral standard is of highest importance; for sanidine standards this is complicated by high melt viscosity during heating. Experiments adding basaltic “zero age glass” (ZAG) to decrease melt viscosity are underway. This has previously been explored by McDowell (1983) with a resistance furnace, but has not been quantitatively addressed with laser heating

  5. Calculation and evaluation of cross-sections and kerma factors for neutrons up to 100 MeV on {sup 16}O and {sup 14}N

    Chadwick, M.B. [California Univ., Livermor, CA (United States). Lawrence Livermore National Lab.; Young, P.G.

    1997-03-01

    We present evaluations of the interaction of neutrons with energies between 20 and 100 MeV with oxygen and nitrogen nuclei, which follows on from our previous work on carbon. Our aim is to accurately represent integrated cross sections, inclusive emission spectra, and kerma factors, in a data library which can be used in radiation transport calculations. We apply the FKK-GNASH nuclear model code, which includes Hauser-Feshbach, preequilibrium, and direct reaction mechanisms, and use experimental measurements to optimize the calculations. We determine total, elastic, and nonelastic cross sections, angle-energy correlated emission spectra for light ejectiles with A {<=} 4 and gamma-rays, and average energy depositions. Our results for charged-particle emission spectra agree well with the measurements of Subramanian et al. We compare kerma factors derived from our evaluated cross sections with experimental data, providing an integral benchmarking of our work. (author). 52 refs.

  6. Evaluated cross section libraries and kerma factors for neutrons up to 100 MeV on {sup 16}O and {sup 14}N

    Chadwick, M.B.; Young, P.G.

    1995-07-01

    We present evaluations of the interaction of 20 to 100 MeV neutrons with oxygen and nitrogen nuclei, which follows on from our previous work on carbon. Our aim is to accurately represent integrated cross sections, inclusive emission spectra, and kerma factors, in a data library which can be used in radiation transport calculations. We apply the FKK-GNASH nuclear model code, which includes Hauser-Feshbach, preequilibrium, and direct reaction mechanisms, and use experimental measurements to optimize the calculations. We determine total, elastic, and nonelastic cross sections, angle-energy correlated emission spectra, for light ejectiles with A{<=}4 and gamma-rays, and average energy depositions. Our results for charged-particle emission spectra agree well with the measurements of Subramanian et al.. We compare kerma factors derived from our evaluated cross sections with experimental data, providing an integral benchmarking of our work. The evaluated data libraries are available as electronic files.

  7. Key comparison BIPM.RI(I)-K5 of the air kerma standards of the ININ, Mexico and the BIPM in 137Cs gamma radiation

    Kessler, C.; Burns, D. T.; Alvarez Romero, J. T.; De la Cruz Hernández, D.; Cabrera Vertti, M. R.; Tovar-Muñoz, V. M.

    2015-01-01

    A direct comparison of the standards for air kerma of the Instituto Nacional de Investigaciones Nucleares (ININ), Mexico, and of the Bureau International des Poids et Mesures (BIPM) was carried out in the 137Cs radiation beam of the BIPM in February 2015. The comparison result, evaluated as a ratio of the ININ and the BIPM standards for air kerma, is 1.0048 with a combined standard uncertainty of 2.0 × 10-3. The results are analysed and presented in terms of degrees of equivalence for entry in the BIPM key comparison database. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  8. Comparison of the standards for air kerma of the LNE-LNHB and the BIPM for {sup 137}Cs gamma radiation

    Allisy-Roberts, P.J.; Kessler, C.; Burns, D.T. [Bureau International des Poids et Mesures (BIPM), 92 - Sevres (France); Delaunay, F.; Donois, M. [CEA Saclay, LNE-LNHB, Lab. National Henri Becquerel 91 - Gif-sur-Yvette (France)

    2009-10-15

    A direct comparison of the standards for air kerma of the Laboratoire National de Metrologie et d'Essais-Laboratoire National Henri Becquerel (LNE-LNHB), France and of the Bureau International des Poids et Mesures (BIPM) was carried out in the {sup 137}Cs radiation beam of the BIPM in November 2008. The result, expressed as a ratio of the LNE-LNHB and the BIPM standards for air kerma, is 0.9984 with a combined standard uncertainty of 2.6 * 10{sup -3}. The result of the earlier direct comparison in {sup 137}Cs {gamma} rays, made in 1995, was 1.0019(30); taking into account the changes made to the BIPM standard and using the present correction factors for the LNE-LNHB standard, the 1995 result becomes 0.9989(26), which is in agreement with the present comparison result. (authors)

  9. Efeito da rega com injecção de ar na humidade do solo, dis­ponibilidade de azoto nítrico, condutividade eléctrica e pro­dutividade da alface cultivada em estufa plástica Effects of irrigation with injection of air in soil moisture, nitrate avail­ability, electrical conductivity and lettuce productivity grown in plastic greenhouse

    C.R. Pivetta

    2010-01-01

    Full Text Available Este trabalho teve como objectivo veri­ficar se a injecção de ar junto a água de rega gota-a-gota enterrada, afecta a humi­dade do solo, a disponibilidade de azoto nítrico, a condutividade eléctrica e o cres­cimento e produtividade da alface. Para tal realizou-se um ensaio com a alface variedade “Mention” cultivada em estufa plástica e localizada na Herdade Experi­mental da Mitra-ICAAM, da Universida­de de Évora -Portugal. Utilizou-se o deli­neamento experimental blocos ao acaso com quatro repetições, com os tratamen­tos: rega com injecção de ar (CAR, e rega sem injecção de ar (SAR. O ar foi introdu­zido na água de rega por meio de um injector “Mazzei”. O teor de humidade na camada superficial (0-0,05 m foi seme­lhante para os dois tratamentos, alcançan­do valores em torno de zero. Em termos de concentração de azoto nítrico (NO 3- os valores observados na camada 0,10­0,20 m, aos 35 e 47 dias após a transplan­tação, foram mais elevados no tratamento CAR. Aos 47 dias após a transplantação, os níveis médios de NO3-foram de 95,33 e 67,94 ppm nos tratamentos CAR e SAR, respectivamente. A densidade radical no tratamento CAR na camada de 0-0,10 m do solo foi 34 % superior em relação ao SAR. A produção comercial não foi afectada pelo tratamento. A falta de resposta da cultura ao acréscimo de azoto nítrico e da densidade radical pode estar relacionada com o curto ciclo da cultura e/ou com o elevado teor de azoto presente no solo, ou ainda com a profundidade que os goteja­dores foram instalados e não com a fun­cionalidade do injector de ar.The objective of the present study was to evaluate the effect of the air injection through subsurface drip irrigation (oxyga­tion in soil moisture, availability of nitro­gen oxide, and electrical conductivity, plant growth and yield of lettuce, variety "Men­tion", cultivated in plastic greenhouse. The experiment was carried out at the Mitra-ICAM, an Experimental

  10. Measuring instruments of the Physikalisch-Technische Bundesanstalt for realization of the units of the dosimetric quantities standard ion dose, photon-equivalent dose and air-kerma

    Engelke, B.A.; Oetzmann, W.; Struppek, G.

    1988-08-01

    The realization of the units of the dosimetric quantities exposure, air-kerma and photon-equivalent dose is an important task of the Physikalisch-Technische Bundesanstalt. The report describes the measuring instruments and other technical equipment as well as the determination of the numerous corrections needed. All data and correction factors required for the realization of the units mentioned above are given in many diagrams and tables. (orig.) [de

  11. Poster - 15: Air kerma rate measurements using a cylindrical free-air ionization chamber on the 05B1-1 beamline at the Canadian Light Source

    Anderson, Danielle; Siegbahn, Albert; Fallone, Gino; Warkentin, Brad [BCCA - Sindi Ahluwalia Hawkins Centre for the Southern Interior, Kelowna BC, Stockholm University, Sweden, Cross Cancer Institute, Alberta Health Services and University of Alberta, Edmonton AB, Cross Cancer Institute, Alberta Health Services and University of Alberta, Edmonton AB (Sweden)

    2016-08-15

    Purpose: The BioMedical Imaging and Therapy (BMIT) beamlines at the Canadian Light Source offer the opportunity for investigating novel imaging and therapy applications of synchrotron radiation. A necessary component in advancing this research, and in progressing toward clinical applications, is the availability of accurate dosimetry that is traceable to a standards institution. However, dosimetry in this setting is challenging. These beams are typically small, non-uniform, and highly intense. This work describes air kerma rate measurements on a BMIT beamline using a free-air ionization chamber (FAC). Methods: The measurements were taken at the 05B1-1 beamline (∼8 – 100 keV) for several beam qualities with mean energies between 20.0 and 84.0 keV. The Victoreen Model 480 cylindrical FAC, with a specially fabricated 0.52 mm diameter aperture, was used to measure air kerma rates. The required correction factors were determined using a variety of methods: tabulated data, measurements, theoretical calculations and Monte Carlo simulations (EGSnrc user code egs-fac). Results: The experimental air kerma rates measured between 0.270 ± 13.6% and 312 ± 2.7% Gy/min. At lower energies (low filtration), the most impactful correction factors were those for ion recombination and for x-ray attenuation. Conclusions: These measurements marked the first absolute dosimetry performed at the BMIT beamlines. The experimental and Monte Carlo methods developed will allow air kerma rates to be measured under other experimental conditions, provide a benchmark to which other dosimeters will be compared, and provide a reference for imaging and therapy research programs on this beamline.

  12. 244-AR Vault Interim Stabilization Project Plan

    LANEY, T.

    2000-01-01

    The 244-AR Vault Facility, constructed between 1966 and 1968, was designed to provide lag storage and treatment for the Plutonium-Uranium Extraction Facility (PUREX) tank farm sludges. Tank farm personnel transferred the waste from the 244-AR Vault Facility to B Plant for recovery of cesium and strontium. B Plant personnel then transferred the treatment residuals back to the tank farms for storage of the sludge and liquids. The last process operations, which transferred waste supporting the cesium/strontium recovery mission, occurred in April 1978. After the final transfer in 1978, the 244-AR facility underwent a cleanout. However, 2,271 L (600 gal) of sludge were left in Tank 004AR from an earlier transfer from Tank 241-AX-104. When the cleanout was completed, the facility was placed in a standby status. The sludge had been transferred to Tank 004AR to support Pacific Northwest National Laboratory [PNNL] vitrification work. Documentation of waste transfers suggests that a portion of the sludge may have been moved from Tank 004AR to Tank 002AR in preparation for transfer back to the AX Tank Farm; however, quantities of the sludge that were moved to Tank 002AR from that transfer must be estimated

  13. A comparison of Australian and Canadian calibration coefficients for air kerma and absorbed dose to water for 60Co gamma radiation.

    Shortt, K R; Huntley, R B; Kotler, L H; Boas, J F; Webb, D V

    2006-06-01

    Australian and Canadian calibration coefficients for air kerma and absorbed dose to water for 60Co gamma radiation have been compared using transfer standard ionization chambers of types NE 2561 and NE 2611A. Whilst the primary standards of air kerma are similar, both being thick-walled graphite cavity chambers but employing different methods to evaluate the Awall correction, the primary standards of absorbed dose to water are quite different. The Australian standard is based on measurements made with a graphite calorimeter, whereas the Canadian standard uses a sealed water calorimeter. The comparison result, expressed as a ratio of calibration coefficients R=N(ARPANSA)/N(NRC), is 1.0006 with a combined standard uncertainty of 0.35% for the air kerma standards and 1.0052 with a combined standard uncertainty of 0.47% for the absorbed dose to water standards. This demonstrates the agreement of the Australian and Canadian radiation dosimetry standards. The results are also consistent with independent comparisons of each laboratory with the BIPM reference standards. A 'trilateral' analysis confirms the present determination of the relationship between the standards, within the 0.09% random component of the combined standard uncertainty for the three comparisons.

  14. A study of the relationship between peak skin dose and cumulative air kerma in interventional neuroradiology and cardiology

    Neil, S; Padgham, C; Martin, C J

    2010-01-01

    A study of peak skin doses (PSDs) during neuroradiology and cardiology interventional procedures has been carried out using Gafchromic XR-RV2 film. Use of mosaics made from squares held in cling film has allowed doses to the head to be mapped successfully. The displayed cumulative air kerma (CAK) has been calibrated in terms of cumulative entrance surface dose (CESD) and results indicate that this can provide a reliable indicator of the PSD in neuroradiology. Results linking PSD to CESD for interventional cardiology were variable, but CAK is still considered to provide the best option for use as an indicator of potential radiation-induced effects. A CESD exceeding 3 Gy is considered a suitable action level for triggering follow-up of patients in neuroradiology and cardiology for possible skin effects. Application of dose action levels defined in this way would affect 8% of neurological embolisation procedures and 5% of cardiology ablation and multiple stent procedures at the hospitals where the investigations were carried out. A close relationship was observed between CESD and dose-area product (DAP) for particular types of procedure, and DAPs of 200-300 Gy cm 2 could be used as trigger levels where CAK readings were not available. The DAP value would depend on the mean field size and would need to be determined for each application.

  15. Kerma in the air at entry surface in thorax pediatric examinations at public hospital in Parana, Brazil

    Santos, Amanda; Porto, Lorena; Bunick, Ana; Paschuk, Sergei; Denyak, Valeriy; Schelin, Hugo; Tilly, Joao; Khoury, Helen

    2011-01-01

    This work consisted in the evaluation of the entrance skin air kerma (ESAK) in pediatric chest x-ray examinations. A study of 186 exams in anterior-posterior, posterior-anterior and lateral projections was carried out for patients with ages ranging from 0 to 15 years. The ESAK was measured with the DoseCal software and Li-Fl thermoluminescent dosimeters. The results were compared with measurements done recently at the same place and with the reference dose values established by the European Community. It was observed that the optimization of the technique and the routine changes suggested in the previous study were not maintained. The charge (mAs) and the ESAK values found in the present study were much higher than the previous one, and the voltage (kVp) values found was lower. The results suggest that the implementation of the Quality Assurance Program could adequate these parameters to the established levels and keep the pediatric examinations more uniform. (author)

  16. Evaluation of pediatrics entrance surface air kerma during chest X-ray examinations in some Khartoum hospitals

    Mohamed, Hassan Ishag Yahya

    2015-10-01

    The aim of this study was to determine the amount of entrance surface air kerma dose in air that can reflect the amount of the risk that the children, are subjected to. The parameters that are involved in this project are x-ray tube current (mA), exposure time (sec.), and focal skin distance (FSD) in cm. ESAK is calculated using the equation: ESAK=(Output (mGy/mAs) x (100/FSD) 2 X mAs) for different examination of different patients. 65 cases were involved in this study, the results show that the ESAK mean value (0.18±0.07) mGy, (0.06±0.07) mGy, (0.045±0.017) mGy and (0.049±0.013) mGy at the hospitals (IBNIOF Omdurman, police, clinic doctor) respectively. IBNIOF presented the highest ESAK (0.18±0.07) mGy, while it was lowest in police (0.045±0.017) mGy. The estimated ESAK value were within the established international reference dose values and also the values obtained in pervious studies however, variations were observed in ESAK values among hospitals under study which could be due to the differences in exposure parameters used. Also tube output has some effect on obtained ESAK. (author)

  17. Effective dose per unit kerma-area product conversion factors in adults undergoing modified barium swallow studies

    Shaw Bonilha, Heather; Wilmskoetter, Janina; Tipnis, Sameer V.; Martin-Harris, Bonnie; Huda, Walter

    2017-01-01

    This study presents an investigation of adult effective dose (E) per unit Kerma-Area Product (KAP) in Modified Barium Swallow Study (MBSS) examinations. PC program for X-ray Monte Carlo (version 2.0.1) was used to calculate patient organ doses during MBSS examinations, which used combined to generate effective dose. Normalized patient doses were obtained by dividing the effective dose (mSv) by the incident KAP (Gy.cm 2 ). Five standard projections were studied and the importance of X-ray beam size and in patient size (body mass index) were investigated. Lateral projections had an average E/ KAP conversion factor of 0.19 ± 0.04 mSv/Gy.cm 2 . The average E/KAP was highest for upper gastrointestinal (GI) anterior- posterior projections (0.27 ± 0.04 mSv/Gy.cm 2 ) and lowest for upper GI posterior-anterior projections (0.09 ± 0.03 mSv/ Gy.cm 2 ). E/KAP always increased with increasing filtration and/or X-ray tube voltage. Reducing the X-ray beam cross-sectional area increased the E/KAP conversion factors. Small patients have the E/KAP conversion factors that are twice those of a standard adult. Conversion factors for effective dose of adult patients undergoing MBSS examinations must account for X-ray beam projection, beam quality (kV and filtration), image size and patient size. (authors)

  18. AR4VI: AR as an Accessibility Tool for People with Visual Impairments

    Coughlan, James M.; Miele, Joshua

    2017-01-01

    Although AR technology has been largely dominated by visual media, a number of AR tools using both visual and auditory feedback have been developed specifically to assist people with low vision or blindness – an application domain that we term Augmented Reality for Visual Impairment (AR4VI). We describe two AR4VI tools developed at Smith-Kettlewell, as well as a number of pre-existing examples. We emphasize that AR4VI is a powerful tool with the potential to remove or significantly reduce a r...

  19. 40Ar/39Ar age spectra from the KBS Tuff, Koobi Fora Formation

    McDougall, I.

    1981-01-01

    40 Ar/ 39 Ar age spectra on anorthoclase phenocrysts from three pumice clasts in the KBS Tuff yield nearly ideal flat patterns, providing good evidence that the samples have remained undisturbed since crystallization. The ages are concordant at 1.88 = 0.02 Myr, and confirm that the KBS Tuff, a key marker bed in the Koobi Fora Formation, northern Kenya, is now very well dated. These results resolve the conflict between earlier 40 Ar/ 39 Ar and conventional K-Ar dating measurements on the KBS Tuff. (author)

  20. 40Ar/39Ar age spectra from the KBS Tuff, Koobi Fora Formation.

    McDougall, Ian

    1981-11-12

    40 Ar/ 39 Ar age spectra on anorthoclase phenocrysts from three pumice clasts in the KBS Tuff yield nearly ideal flat patterns, providing good evidence that the samples have remained undisturbed since crystallization. The ages are concordant at 1.88±0.02 Myr, and confirm that the KBS Tuff, a key marker bed in the Koobi Fora Formation, northern Kenya, is now very well dated. These results resolve the conflict between earlier 40 Ar/ 39 Ar and conventional K-Ar dating measurements on the KBS Tuff.

  1. Effects of shock pressure on 40Ar-39Ar radiometric age determinations

    Davis, P.K.

    1977-01-01

    The relation of shock to the drop in the 40 *Ar/ 39 *Ar ratio seen at high release temperatures in some neutron-irradiated lunar samples is investigated through measurements of the 40 *Ar/ 39 *Ar ratio in gas samples released by stepwise heating of rock samples previously subjected to shock, either in the laboratory or in nature. Explosives were used to shock solid pieces and powder of a basalt from a diabase dike in Liberia to calculated pressures of 65, 150 and 270 kbar. These, an unshocked sample of the powder, two naturally shocked samples from the Brent impact crater in Canada, one unshocked sample from near the crater, and appropriate monitors were irradiated. Ar from stepwise heating was analyzed. The unshocked basalt shows a good 40 *Ar/ 39 *Ar plateau at age 198 +-9 m.y. in agreement with a previous result of 186 +- 2 m.y. The shocked samples contain varying amounts of implanted atmospheric Ar, the isotopes of which have experienced mass fractionation. This effect is small enough in four samples so that the linearity of their graphs of 39 *Ar/ 40 Ar vs 36 Ar/ 40 Ar is evidence of a plateau. The ages of these samples are then 201 +- 10, 205 +- 12 and 201 +-9 m.y. It appears that the shock has had little effect on the 40 Ar- 39 Ar age spectrum, although the release patterns of the 39 *Ar are shifted downward by the order of 200 0 C. Shock implantation of Ar was at lower shock pressure, in the presence of less Ar, and into a less porous material than previously demonstrated. The Brent Crater samples do not all show good plateaus, but do indicate an age of 420 m.y. for the crater event and 795 +- 24 m.y. for the rock formation, in agreement with previous results. None of the 40 *Ar/ 39 *Ar profiles shows a drop at high temperature, but a possible role of shock implantation of Ar is indicated in the production of this effect. Further experiments are suggested. (author)

  2. Photodissociation dynamics of Ar2(+) and Ar3(+) excited by 527 nm photons.

    Lepère, V; Picard, Y J; Barat, M; Fayeton, J A; Lucas, B; Béroff, K

    2009-05-21

    The photofragmentation dynamics of Ar(2)(+) and Ar(3)(+) clusters has been investigated at a 527 nm wavelength (2.35 eV) using a setup that allows simultaneous detection of the ionic and neutral fragments in a coincidence experiment. Measurement of positions and times of flight enables in principle a complete description of the fragmentation dynamics. The photofragmentation dynamics of Ar(3)(+) clusters is similar to that of Ar(2)(+) with, in addition, the ejection of a third fragment that can be neutral or ionized via a resonant electron capture. This is attributed to the triangular geometry of the Ar(3)(+) ion.

  3. Single electron capture by state-prepared Ar2+ projectiles in Ar

    Puerta, J.; Huber, B.A.

    1985-03-01

    Electron capture by state-selected Ar 2+ projectiles in Ar has been studied at low collision energies ( 2+ ions are measured explaining existing discrepancies of partial and total cross sections in the Ar 2+ /Ar collision system. Although highly excited metastable ions ( 5 D 4 0 , 3 F 4 0 ) represent a minor contamination of a non-prepared Ar 2+ beam (proportional1%), their contributions are found to dominate the capture process due to cross section values larger than 10 -15 cm 2 . (orig.)

  4. 3 to 15 keV Ar+ induced Auger electron emission from Si and Ar

    Kempf, J.; Kaus, G.

    1977-01-01

    Ar + induced Auger electrons from Si and Ar were investigated at bombardment energies between 3-15 keV and target currents of a few μA. The Auger electron yields were compared with secondary ion yields of Si and Ar by simultaneous SIMS-AES measurements. In the ion induced Auger spectra of Si five Auger peaks and in the Ar spectra three Auger peaks were observed. The ion induced Auger electron yield of Si and Ar were found to be strongly dependent upon the primary ion energy. 'Bulk like' and 'atomic like' Auger transitions of ion induced Auger electrons of Si were observed. (orig.) [de

  5. Efeito da adição de polpa, carboximetilcelulose e goma arábica nas características sensoriais e aceitação de preparados em pó para refresco sabor laranja Effect of adding pulp, carboxymethyl cellulose and arabic gum to sensory characteristics and acceptance of powdered orange-flavored refreshments

    Valentina de Fátima Caleguer

    2007-06-01

    Full Text Available O trabalho teve como objetivo avaliar o efeito sensorial da adição de polpa, carboximetilcelulose (CMC e goma arábica (fibra nos atributos e aceitação de refrescos de laranja. Utilizou-se uma amostra padrão e outras formuladas com polpa, CMC, fibra e todos os ingredientes. Foram realizadas análises físico-químicas (pH, acidez titulável, sólidos solúveis, vitamina C, cor e turbidez, e as amostras também foram caracterizadas pela técnica de Perfil Livre. Na análise descritiva utilizou-se 14 provadores e, para a avaliação dos resultados foi empregada a Análise Procrustes Generalizada. As amostras caracterizadas como diferentes (padrão, CMC, fibra foram submetidas a teste de aceitação. Os refrescos foram caracterizados e separados com base em atributos de aparência (cor laranja e turbidez, aroma (adocicado e laranja, sabor (doce, laranja e ácido e textura (viscosidade. O padrão e a amostra com polpa, que não foram diferenciadas sensorialmente, apresentaram menor intensidade de cor laranja e turbidez, e foram consideradas menos encorpadas e mais ácidas. As amostras com CMC e fibra se diferenciaram do padrão e apresentaram comportamento intermediário. A formulação com todos os ingredientes apresentou características opostas: maior intensidade de cor e turbidez, mais encorpada e menos ácida. As amostras com CMC e fibra foram mais aceitas que o padrão.The aim of this work was to evaluate the sensory effect of adding pulp, carboxymethyl cellulose (CMC and arabic gum (fiber to characteristics and acceptance of powdered orange flavored soft drinks. A standard sample and another formulated with pulp, CMC, fiber with all the ingredients were used. Physicochemical analyses (pH, titratable acidity, soluble solids, vitamin C, color and turbidity were applied and samples were characterized by Free-Choice Profiling. Fourteen panelists were used in the descriptive analysis and the Generalized Procrustes Analysis was applied to

  6. 37Ar and 39Ar in meteorites and the spatial cosmic ray gradient

    Heusser, G.; Schaeffer, O.A.

    1977-01-01

    Cosmic-ray-produced 37 Ar (tsub(1/2) = 35 days), and 39 Ar (tsub(1/2) = 269 years) in the Fe-Ni phase of meteorites have been studied in connection with their implications for the radial gradient of cosmic ray particles. For the chondrite, Canon City, which fell on October 27, 1973, 20.1 +- 1.5 dpm/kg FeNi of 37 Ar and 22.5 +- 1.4 dpm/kg FeNi of 39 Ar was found. Usually, the 37 Ar/ 39 Ar ratio is used to deduce a spatial gradient. However, 37 Ar data reported in the literature are inconsistent. They fluctuate much more than could be accounted for by different orbits and the anticipated correlation with the cosmic ray neutron registrations is rather weak. Consequently, the 37 Ar/ 39 Ar-derived gradient has a low confidence level. On the other hand, 39 Ar activities group close to a mean value of 22.5 dpm/kg FeNi and appear to be almost independent of the different meteoroid orbits. A comparison of measured 39 Ar activities in meteorites with those calculated for orbits obtained from fireball data shows that a gradient of 10%/Au or less is reconcilable with the experimental findings. The average gradient (E > 200 MeV) during the last 500 years was probably not much larger than that measured presently by the Pioneer 10 and 11, and Helios spacecrafts. (Auth.)

  7. 40Ar/39Ar laser-probe dating of diamond inclusions from the Premier kimberlite

    Phillips, D.; Onstott, T.C.; Harris, J.W.; Strathclyde Univ., Glasgow

    1989-01-01

    Inclusions encapsulated by diamonds at the time of their formation provide a means for determining diamond crystallization ages and the chemistry of the surrounding upper mantle at that time. Sm-Nd studies of peridotitic inclusions, from Cretaceous-age kimberlites in southern Africa, suggest that the diamonds formed 3.3 Gyr ago. By contrast, eclogite-suite inclusions generally yield younger ages, sometimes approaching the time of kimberlite eruption. Here we report the results of 40 Ar/ 39 Ar laser-probe analyses of individual eclogitic clinopyroxene inclusions from Premier diamonds, which yield a mean age of 1,198±14 Myr. This age agrees well with Sm-Nd and 40 Ar/ 39 Ar analyses on similar Premier inclusions, and is indistinguishable from the inferred time of emplacement of the host kimberlite (1,150-1,230 Myr), which implies that diamond formation was essentially synchronous with kimberlite generation. The extrapolated non-radiogenic 40 Ar/ 36 Ar ratio of 334±102 is similar to the present-day atmospheric composition. This value is inconsistent with Sr and Nd isotopic signatures from Premier eclogite inclusions, which suggest a depleted mantle source ( 40 Ar/ 36 Ar>20,000). Pre-entrapment equilibration of the inclusions with an 36 Ar-rich fluid is the most probable explanation for the low non-radiogenic ( 40 Ar/ 36 Ar) composition. (author)

  8. Evidence of interatomic Coulombic decay in ArKr after Ar 2p Auger decay

    Morishita, Y; Saito, N; Suzuki, I H; Fukuzawa, H; Liu, X-J; Sakai, K; Pruemper, G; Ueda, K; Iwayama, H; Nagaya, K; Yao, M; Kreidi, K; Schoeffler, M; Jahnke, T; Schoessler, S; Doerner, R; Weber, T; Harries, J; Tamenori, Y

    2008-01-01

    We have identified interatomic Coulombic decay (ICD) processes in the ArKr dimer following Ar 2p Auger decay, using momentum-resolved electron-ion-ion coincidence spectroscopy and simultaneously determining the kinetic energy of the ICD electron and the KER between Ar 2+ and Kr + . We find that the spin-conserved ICD processes in which Ar 2+ (3p -3 3d) 1 P and 3 P decay to Ar 2+ (3p -2 ) 1 D and 3 P, respectively, ionizing the Kr atom, are significantly stronger than the spin-flip ICD processes in which Ar 2+ (3p -3 3d) 1 P and 3 P decay to Ar 2+ (3p -2 ) 3 P and 1 D, respectively

  9. 40Ar-39Ar age determinations on the Owyhee basalt of the Columbia plateau

    Bottomley, R.J.; York, D.

    1976-01-01

    40 Ar/ 39 Ar step-heating analyses have been performed on 11 samples of basalt from sites near Owyhee Reservoir of southeastern Oregon, U.S.A. These rocks were extruded during the great flood basalt episode of the Pacific Northwest. The whole-rock points are highly correlated on a plot of 40 Ar/ 36 Ar versus 39 Ar/ 36 Ar, corresponding to a common age of the samples of 14.3+-0.3 m.y. Inspite of this, individual 'plateau' plots of the age versus fraction of 39 Ar released do not give good plateaux. These age spectra exhibit to varying degrees a common structure in which lower age values are found at higher temperatures. This pattern may result from a closed-system redistribution of the argon isotopes. The usefulness of grinding the basalts in removing a loosely held atmospheric argon component is confirmed. (Auth.)

  10. A conversion method of air-kerma from the primary, scatter and leakage radiations to ambient dose equivalent for calculating the mamography x-ray shielding barrier

    Kharrati, H.

    2005-01-01

    The primary, scatter, and leakage doses(in Gy), which constitute the data base for calculating shielding requirements for x-ray facilities, are often converted to the equivalent dose (in sievert) by using a constant of conversion of 1.145Sv/Gy. This constant is used for diagnostic radiology as well as for mammography spectra, and is derived by considering an exposure of 1 R corresponds to an air kerma of 8.73 m Gy, which renders by tradition an equivalent dose of 10 mSv. However, this conversion does not take into account the energy dependence of the conversion coefficients relating air kerma to the equivalent dose as described in ICRU report. Moreover, current radiation protection standards propose the use of the quantity ambient dose equivalent in order to qualify the efficiently of given radiation shielding. Therefore, in this study, a new approach has been introduced for derivation ambient dose equivalent from air kerma to calculate shielding requirements in mammography facilities. This new approach has been used to compute the conversion coefficients relating air kerma to ambient dose equivalent for mammography reference beam series of the Netherlands Metrology Institute Van Swinden Laboratorium (NMi), National Institute of Standards and Technology (NIST), and International Atomic Energy Agency (AIEA) laboratories. The calculation has been performed by the means of two methods which show a maximum deviation less than 10%2 for the primary, scatter, and leakage radiations. The results show that the conversion coefficients vary from 0.242 Sv/ Gy to 0.692 Sv/Gy with an average value of 0.436 Sv/Gy for the primary and the scatter radiations, and form 0.156 Sv/Gy to 1.329 Sv/Gy with an average value of 0.98 Sv/Gy for the leakage radiation. Simpkin et al. using an empirical approach propose a conversion value of 0.50 Sv/Gy for the mammography x-ray spectra. This value approximately coincides with the average conversion value of 0.436 Sv/Gy obtained in this work for

  11. On mechanism of Ar(3p54p) states excitation in low-energy Ar-Ar collisions

    Kurskov, S Y; Kashuba, A S

    2009-01-01

    The present work is devoted to study of Ar(3p 5 4p) states excitation in binary low-energy Ar-Ar collisions. The results of the experimental investigation of excitation cross sections of Ar I 4p'[l/2] 1 , 4p'[3/2] 1 , 4p'[3/2] 2 and 4p[3/2] 2 levels in the collision energy range from threshold up to 500 eV (cm) and degree of polarization for 4s[3/2] 2 0 -4p'[l/2] 1 and 4s[3/2] 2 0 -4p[3/2] 2 transitions in this energy range are represented.

  12. Ars Baltica-verkoston puheenjohtajuus Suomeen Risto Ruohoselle

    1999-01-01

    1990. a. loodud võrgustiku Ars Baltica sekretariaat (Ars Baltica Contact Point & Communication Center) tuleb Kielist Tallinnasse Eesti kultuuriministeeriumi kuni aastani 2002 (Suur-Karja 23). Ars Baltica (ühendus)

  13. A flavor of 40Ar-39Ar geochronology research at lIT Bombay

    Pande, Kanchan

    2017-01-01

    Geochronology based on radiogenic isotopes has become an invaluable tool in earth sciences. Several radioactive parent-daughter systems of varying half-lives such as Rb-Sr, Sm-Nd, K-Ar have been traditionally used by researchers for determining the timing of geological and planetary processes. 40 Ar- 39 Ar dating, a variant of the K-Ar system, is a well-established and versatile method of determining the eruptive ages of volcanic rocks and the ∼150-500° C thermal histories of a variety of more slowly cooled igneous and metamorphic rocks. In the 40 Ar- 39 Ar method the sample is irradiated by fast neutrons in a nuclear reactor to convert some of 39 K into 39 Ar. The fixed natural ratio 39 K/ 40 K provides estimate for the parent 40 K by measuring 39 Ar. In order to know the conversion factor of 39 K to 39 Ar and to take care of other nuclear interfering reactions a sample of known K-Ar age is irradiated along with the unknown. The age of the unknown is then derived by comparison with the monitor sample of known age

  14. Ar-40/Ar-39 Studies of Martian Meteorite RBT 04262 and Terrestrial Standards

    Park, J.; Herzog, G. F.; Turrin, B.; Lindsay, F. N.; Delaney, J. S.; Swisher, C. C., III; Nagao, K.; Nyquist, L. E.

    2014-01-01

    Park et al. recently presented an Ar-40/Ar-39 dating study of maskelynite separated from the Martian meteorite RBT 04262. Here we report an additional study of Ar-40/Ar-39 patterns for smaller samples, each consisting of only a few maskelynite grains. Considered as a material for Ar-40/Ar-39 dating, the shock-produced glass maskelynite has both an important strength (relatively high K concentration compared to other mineral phases) and some potentially problematic weaknesses. At Rutgers, we have been analyzing small grains consisting of a single phase to explore local effects that might be averaged and remain hidden in larger samples. Thus, to assess the homogeneity of the RBT maskelynite and for comparison with the results of, we analyzed six approx. 30 microgram samples of the same maskelynite separate they studied. Furthermore, because most Ar-40/Ar-39 are calculated relative to the age of a standard, we present new Ar-40/Ar-39 age data for six standards. Among the most widely used standards are sanidine from Fish Canyon (FCs) and various hornblendes (hb3gr, MMhb-1, NL- 25), which are taken as primary standards because their ages have been determined by independent, direct measurements of K and A-40.

  15. Evaluation of entrance skin air kerma in digital and conventional pediatric chest examinations performed in Parana-Brazil

    Oliveira, Ana L.R.; Schelin, Hugo R.; Lunelli, Neuri; Paschuk, Sergei; Tilly Jr, Joao G.; Rogacheski, Enio; Khoury, Helen J.; Ferreira, Jose R.L.

    2008-01-01

    Full text: In pediatric radiology it is important to evaluate patient exposure due to the high sensitivity of his/her tissue and his/her relatively longer life expectancy, which may increase the chance of radiogenic cancer development. Special attention is necessary when digital systems are used since a high dosage level for the patient may go unnoticed because the resulting image is not overexposed. The purpose of this work is to evaluate the Entrance Skin Air Kerma (ESAK) in pediatric patients submitted to digital and conventional chest examinations performed in the State of Parana, located in the Southern region of Brazil. The survey was performed in two hospitals, one located in Curitiba, the Capital of the State (A) and the other in the city of Cascavel (B). Hospital A uses a conventional image system and Hospital B uses a CR digital system. The study group consisted of 50 patients (from 2 days to six years of age) undergoing chest PA/AP examinations. At the time of the examination, the exposure parameters (kV, mAs, focal-film distance, etc) and the gender, height, weight and age of the patient were recorded. To evaluate the Entrance Skin Air Kerma (ESAK), two TLD-100 dosimeters were packaged in a polyethylene case, heat sealed and placed on the surface of each patient. The TLDs were calibrated the Metrology Laboratory of Ionizing Radiation of the Federal University of Pernambuco. The TLDs were processed on a Victoreen readout system model 2800M. The results showed that the kilovoltage values used in Hospital A are in the range of 46 to 65 kV with the average value of 51,7 kV, while the ones in Hospital B are in the range of 65 to 80 kV. On the other hand, even though hospital B uses the CR system, the mAs used for the chest exams are 4 times higher than the ones used in Hospital A. For Hospital A, the mean ESAK value was 0.044 mGy (min: 0.08 and max 0.146 mGy), and for Hospital B the mean ESAK value was 0.368 mGy (min: 0.021 and max 1.21mGy). The results made

  16. Ars ornata / Kadri Mälk

    Mälk, Kadri, 1958-

    1998-01-01

    V rahvusvaheline ehtekunsti konverents 'Ars ornata Europeana' juuni lõpus Stockholmis. New Yorgis elava kuraatori Charon Kranseni ja prantsuse ehtekunstniku Christophe Burger' juhitud vestlusringidest. 1997. a. Pariisis loodud International Craft Design Association'ist (ICDA).

  17. ARS 01 Helsingi Kiasmas / Tarmo Virki

    Virki, Tarmo

    2001-01-01

    Helsingis Kiasmas avatud rahvusvahelisest kunstinäitusest ARS 01 alapealkirjaga "Avanevaid perspektiive", kus esines oma töödega ka Marko Mäetamm. Näituse raames toimuvast Santiago Sierra kunstiprojektist kodututega

  18. Evaluated cross-section libraries and kerma factors for neutrons up to 100 MeV on 12C

    Chadwick, M.B.; Blann, M.; Cox, L.; Young, P.G.; Meigooni, A.

    1995-01-01

    A program is being carried out at Lawrence Livermore National Laboratory to develop high-energy evaluated nuclear data libraries for use in Monte Carlo simulations of cancer radiation therapy. In this report we describe evaluated cross sections and kerma factors for neutrons with incident energies up to 100 MeV on 12 C. The aim of this effort is to incorporate advanced nuclear physics modeling methods, with new experimental measurements, to generate cross section libraries needed for an accurate simulation of dose deposition in fast neutron therapy. The evaluated libraries are based mainly on nuclear model calculations, benchmarked to experimental measurements where they exist. We use the GNASH code system, which includes Hauser-Feshbach, preequilibrium, and direct reaction mechanisms. The libraries tabulate elastic and nonelastic cross sections, angle-energy correlated production spectra for light ejectiles with A≤and kinetic energies given to light ejectiles and heavy recoil fragments. The major steps involved in this effort are: (1) development and validation of nuclear models for incident energies up to 100 MeV; (2) collation of experimental measurements, including new results from Louvain-la-Nueve and Los Alamos; (3) extension of the Livermore ENDL formats for representing high-energy data; (4) calculation and evaluation of nuclear data; and (5) validation of the libraries. We describe the evaluations in detail, with particular emphasis on our new high-energy modeling developments. Our evaluations agree well with experimental measurements of integrated and differential cross sections. We compare our results with the recent ENDF/B-VI evaluation which extends up to 32 MeV

  19. Assessment of natural radioactivity in soil samples and comparison of direct and indirect measurement of environmental air kerma rate

    Chinnaesakki, S.; Manish Chopra; Sartandel, S.J.; Bara, S.V.; Tripathi, R.M.; Puranik, V.D.; Sanjeev Kumar; Vishal Arora; Bajwa, B.S.

    2011-01-01

    This study presents the high purity germanium (HPGe) gamma spectrometric measurement of natural radioactivity mainly due to 226 Ra, 232 Th and 40 K in soil samples collected in Ferozepur and Faridkot district of Punjab, India. 226 Ra activity varied from 28.6 to 51.1 Bq kg -1 with the mean of 39.7 Bq kg -1 . The range and mean activity of 232 Th were 42.9 - 73.2 and 58.2 Bq kg -1 , respectively. 40 K activity was in the range of 470.9 - 754.9 Bq kg -1 with the mean of 595.2 Bq kg -1 . The air kerma rate (AKR) at 1 m height from the ground was also measured using gamma survey meter in all the sampling locations, which was ranging from 92.1 to 122.8 nGy h -1 with the mean of 110.6 nGy h -1 . The radiological parameters such as Raeq and activity index of the soil samples were also evaluated, which are the tools to assess the external radiation hazard due to building materials. The mean and range of the Raeq values were 168.7 and 132.9 - 210.4 Bq kg -1 , respectively, whereas the activity index varied from 0.5 to 0.8 with the mean value of 0.62. These indices show that the indoor external dose due to natural radioactivity in the soil used for the construction will not exceed the dose criteria. The AKR was also evaluated from soil activity concentration and altitude correction of cosmic radiation contribution. The statistical tests such as Pearson correlation, spearman rank correlation, box and whisker plot, the Wilcoxon/Mann-Whitney test and chi-square test, were used to compare the measured AKR with evaluated AKR, which indicates good correlation. (author)

  20. Vector analyzing power and cross section for the reactions 40Ar(d(pol),p)41Ar and 40Ar(d(pol),t)39Ar

    Sen, S.; Darden, S.E.; Yoh, W.A.; Berners, E.D.

    1975-01-01

    Angular distributions of vector analyzing power and cross section for the reactions 40 Ar(d,p) 41 Ar and 40 Ar(d,t) 39 Ar have been measured at an incident deuteron energy of 14.83 MeV. The bound-state data in the (d,p) reaction and the (d,t) data are compared to DWBA calculations. The data for the neutron-unbound states are analyzed in the framework of the DWBA using (i) a form factor for weakly bound neutron and (ii) a resonance form factor, following the approach of Vincent and Fortune. The j-dependence of the (d,p) vector analyzing power permits definite spin-parity assignments to be made for 19 neutron-bound and 4 neutron unbound states in 41 Ar with excitation energy up to 6.57 MeV. Tentative Jsup(π) assignments have been made for 3 states. The l-value for the 5.62 MeV states has been determined. Data for the observed unbound states are found to be equally well reproduced by the type (i) calculations as by the type (ii) calculations. The (d,t) vector cnalyzing power data show definite J-dependence although not as strongly as in the (d,p) reaction. For relatively weakly excited states a pre-knowledge of the l-value of the transition is desirable for an unambiguous spin assignment. In general, the J-dependence in the (d,t) vector analyzing power can be utilized for definitive Jsup(π) assignments. On this basis, Jsub(π) values have been assigned for seven states in 39 Ar with excitation energies up to 4.47MeV excitation. Possible spin values for three other states are suggested. Spectroscopic factors fo the states in 41 Ar and 39 Ar have been extracted and are in fair agreement with those obtained by other workers. (Auth.)

  1. Jumps in binomial AR(1) processes

    Weiß , Christian H.

    2009-01-01

    Abstract We consider the binomial AR(1) model for serially dependent processes of binomial counts. After a review of its definition and known properties, we investigate marginal and serial properties of jumps in such processes. Based on these results, we propose the jumps control chart for monitoring a binomial AR(1) process. We show how to evaluate the performance of this control chart and give design recommendations. correspondance: Tel.: +49 931 31 84968; ...

  2. AR4VI: AR as an Accessibility Tool for People with Visual Impairments.

    Coughlan, James M; Miele, Joshua

    2017-10-01

    Although AR technology has been largely dominated by visual media, a number of AR tools using both visual and auditory feedback have been developed specifically to assist people with low vision or blindness - an application domain that we term Augmented Reality for Visual Impairment (AR4VI). We describe two AR4VI tools developed at Smith-Kettlewell, as well as a number of pre-existing examples. We emphasize that AR4VI is a powerful tool with the potential to remove or significantly reduce a range of accessibility barriers. Rather than being restricted to use by people with visual impairments, AR4VI is a compelling universal design approach offering benefits for mainstream applications as well.

  3. Estudo comparativo do resfriamento de laranja valência com ar forçado e com água

    Teruel,Bárbara; Cortez,Luís; Neves Filho,Lincoln

    2003-01-01

    Este trabalho apresenta um estudo para comparar o resfriamento rápido de laranja Valência (Citrus sinensis O.), com ar forçado e com água gelada. O sistema de resfriamento rápido com ar forçado operou com um fluxo de ar de 1.933m³/h (3 l/s por kg de produto resfriado), a uma temperatura de 1ºC e UR=88,4 ± 2,0%, com uma velocidade do ar em torno de 1m/s. Nos experimentos com água gelada foi utilizado um sistema de imersão, com uma capacidade de 0,23m³ de água a uma temperatura de aproximadamen...

  4. The effects of acid treatment and sample preparation on 40Ar/39Ar ages

    Morgan, L. E.; Davidheiser, B.; Kuiper, K.; Wijbrans, J. R.

    2011-12-01

    Practitioners of K-Ar and 40Ar/39Ar geochronology regularly use dilute acids (typically 5-10% hydrofluoric acid (HF)) to clean mineral grains prior to irradiation (in the case of 40Ar/39Ar), and analysis (e.g. Evernden and Curtis, 1965; Dalrymple, 1967). This treatment has been shown to reduce contamination from atmospheric Ar, which consists largely of 40Ar and thus must be differentiated from radiogenic 40Ar* (Evernden and Curtis, 1965). Acid treatments can also remove fine grained material attached to mineral grains, such as glass shards or devitrified glass, which can affect analyses and is difficult to remove by other means (Evernden and Curtis, 1965). Such treatments were originally examined for their efficacy in reducing atmospheric argon contamination (Dalrymple, 1967) but were not assessed for the possibility of leaching Ar* or K differentially, which would affect both K-Ar and 40Ar/39Ar ages. Indeed, Evernden and Curtis (1965) state that they are simply removing the "outer portions of the crystals" and apparently do not account for the potential for leaching of 40Ar* or K from the mass of their host mineral. Moreover, the capabilities of the K-Ar system in the 1960s was limited to a precision of ca. 3-4% on samples of 1-3 Ma (Cox and Dalrymple, 1967). Effects of smaller magnitude could not have been detected at the time. As the developments of the 40Ar/39Ar system and modern mass spectrometer technology have allowed for precision to approach 0.1%, the potential effects of acid treatment during sample preparation warrant revisiting. Additionally, the use of Calgon for sample disintegration has not previously been quantitatively assessed but is used extensively in some laboratories. Here we present a series of experiments from co-irradiated Fish Canyon sanidine (FCs) and Mes-4 (Kuiper et al., 2008). FCs is used as the mineral standard following standard procedures. Mes-4 splits were treated with H2O (10 minutes, ultrasonic), Calgon (10%, overnight at 50

  5. Age measurements of potassium-bearing sulfide minerals by the 40Ar/39Ar technique

    Czamanske, G.K.; Lanphere, M.A.; Erd, R.C.; Blake, M.C. Jr.

    1978-01-01

    K-Ar ages have been determined for sulfide minerals for the first time. The occurrence of adequate amounts of potassium-bearing sulfides with ideal compositions K 3 Fe 10 S 14 (approximately 10 wt.% K) and KFe 2 S 3 (approximately 16 wt.% K) in samples from a mafic alkalic diatreme at Coyote Peak, California, prompted an attempt to date these materials. K 3 Fe 10 S 14 , a massive mineral with conchoidal fracture, gives an age of 29.4 +- 0.5 m.y. ( 40 Ar/ 39 Ar), indistinguishable from the 28.3 +- 0.4 m.y. ( 40 Ar/ 39 Ar) and 30.2 +- 1.0 m.y. (conventional K-Ar) ages obtained for associated phlogopite (8.7 wt.% K). KFe 2 S 3 , a bladed, fibrous sulfide, gives a younger age, 26.5 +- 0.5 m.y. ( 40 Ar/ 39 Ar), presumably owing to Ar loss. (Auth.)

  6. Geochronology and thermochronology by the sup 40 Ar/ sup 39 Ar method

    McDougall, I. (Australian National Univ., Canberra (Australia)); Harrison, T.M. (State Univ. of New York, Albany, NY (USA))

    1988-01-01

    This work is a response to the authors' belief that there is a need for a monograph on {sup 40}Ar/{sup 39}Ar dating to provide concise knowledge concerning the application of this method to geological studies. They aim to provide a reasonably comprehensive but by no means exhaustive coverage of the principles and practices of {sup 40}Ar/{sup 39}Ar dating, with emphasis on interpretation of results. In attempting to provide an overview of the current state of knowledge, they commonly cite examples from the available literature. They draw rather heavily upon their own work, because they feel comfortable with their own examples. (author).

  7. 40Ar/39Ar age and thermal history of the Kirin chondrite

    Wang, S.; McDougall, I.; Tetley, N.; Harrison, T.M.

    1980-01-01

    The Kirin meteorite, a large (> 2800 kg) H5 chondrite, fell in Kirin Province, China in 1976. A sample from each of the two largest fragments (K-1. K-2) yield 40 Ar/ 39 Ar total fusion ages of 3.63 +- 0.02 b.y. and 2.78 +- 0.02 b.y. respectively. 40 Ar/ 40 Ar age spectra show typical diffusional argon loss profiles. Maximum apparent ages of 4.36 b.y. (K-1) and approx. 4.0 b.y. (K-2) are interpreted as possible minimum estimates for the age of crystallization of the parent body. (orig./ME)

  8. Measurement of kVp, PPV and air kerma values in function of the electric current quantity and the focus-detector distance in one X-ray equipment

    Lucena, Rodrigo F. de; Potiens, Maria da Penha A.; Vivolo, Vitor

    2009-01-01

    The objective of this work was to study the behavior of the X-ray equipment Pantak/Seifert, model MXR-160/22 of the calibration laboratory of IPEN, LCI, operating in the diagnostic radiology radiation quality RQR 5 (70 kV). For this evaluation it was used a noninvasive meter PTW, Diavolt TM model. The measurements of kVp, PPV and Dose (air kerma), were made varying the electric current and distance between the focal point and the meter. This behavior is described in the literature and was expected in the analysis of the measurements for comparison purposes. For the tests where it was only increased the electric current it was waited a linear increase of the dose (air kerma), but not a variation in the kVp and PPV. The measurements had corresponded to the waited behavior, since the Dose (air kerma) measurements presented a linear increase with the increase of the electric current and the kVp and PPV values showed a variation less than 2%. In the corresponding measurements increasing the distance between focal point and meter, it was waited the exponentially decreasing of the Dose (air kerma) and again a small variation or no variation of the PPV and kVP with the increase of the distance. Over again the measurements corresponded to the expected, where the Dose (air kerma) decreased exponentially and the PPV and the kVp had a variation less than 1.5%. (author)

  9. European comparison of Monte Carlo codes users on the uncertainty calculations of air kerma determined in front of a cesium-137 beam; Intercomparaison europeenne d'utilisateurs de codes Monte Carlo pour le calcul d'incertitudes sur le kerma dans l'air determine dans un faisceau de cesium-137

    De carlan, L.; Bordy, J.M.; Gouriou, J. [CEA Saclay, LIST, Laboratoire National Henri Becquerel, Laboratoire de Metrologie de la Dose, 91191 Gif-Sur-Yvette Cedex (France)

    2011-07-15

    Within the framework of the European project CONRAD (Coordinated Network for Radiation Dosimetry, contract FP6-12684) coordinated by EURADOS (European Radiation Dosimetry group), WP4 was devoted to numerical dosimetry under the title 'Uncertainty assessment in computational dosimetry: an intercomparison of approaches'. Within this activity, a working group sent a list of eight exercises, dealing with radiation transport of photons, neutrons, protons and electrons, to be solved by the international community. This paper presents exercise number 4, dealing with the calculation of air kerma for a {sup 137}Cs beam. This problem was aimed at estimating the components of the uncertainty on the air kerma which cannot be measured, namely those due to geometrical data such as the source location, the diameter of the collimator, the material density, etc. 12 institutes of 10 different countries took part in this work, showing the interest in this proposal. (authors)

  10. Pin-photodiode array for the measurement of fan-beam energy and air kerma distributions of X-ray CT scanners.

    Haba, Tomonobu; Koyama, Shuji; Aoyama, Takahiko; Kinomura, Yutaka; Ida, Yoshihiro; Kobayashi, Masanao; Kameyama, Hiroshi; Tsutsumi, Yoshinori

    2016-07-01

    Patient dose estimation in X-ray computed tomography (CT) is generally performed by Monte Carlo simulation of photon interactions within anthropomorphic or cylindrical phantoms. An accurate Monte Carlo simulation requires an understanding of the effects of the bow-tie filter equipped in a CT scanner, i.e. the change of X-ray energy and air kerma along the fan-beam arc of the CT scanner. To measure the effective energy and air kerma distributions, we devised a pin-photodiode array utilizing eight channels of X-ray sensors arranged at regular intervals along the fan-beam arc of the CT scanner. Each X-ray sensor consisted of two plate type of pin silicon photodiodes in tandem - front and rear photodiodes - and of a lead collimator, which only allowed X-rays to impinge vertically to the silicon surface of the photodiodes. The effective energy of the X-rays was calculated from the ratio of the output voltages of the photodiodes and the dose was calculated from the output voltage of the front photodiode using the energy and dose calibration curves respectively. The pin-photodiode array allowed the calculation of X-ray effective energies and relative doses, at eight points simultaneously along the fan-beam arc of a CT scanner during a single rotation of the scanner. The fan-beam energy and air kerma distributions of CT scanners can be effectively measured using this pin-photodiode array. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  11. Polineuropatia periférica arsenical: tratamento com penicilamina. Dosagem de arsênico inorgânico em nervo periférico, sangue e urina Arsenical peripheral polyneuropathy: treatment with penicillamine and determination of the concentrations of inorganic arsenic in peripheral nerve, blood, and urine. A case report

    Abrão Anghinah

    1974-09-01

    Full Text Available Os autores registram caso de paciente na qual, após intoxicação aguda por arsênico inorgânico, instalou-se quadro de polineuropatia periférica. Foram verificadas altas concentrações de arsênico no nervo periférico estudado (1,48 mg/100 g peso seco, e 0,49 mg/100 g peso fresco e na urina. Antes do tratamento com penicilamina a quantidade de arsênico excretada na urina era de 80,0 micro/100 ml; após 7 dias de tratamento a excreção passou a ser de 150,2 micrograma/100 ml. Estes resultados bioquímicos foram acompanhados de progressiva melhora clínica.Report of a case of acute intoxication by inorganic arsenic with a picture of peripheral polyneuropathy. High concentrations of arsenic were found in the peripheral nerve studied (1.48 mg/100 g fresh tissue; 0,40 mg/100 g dry tissue blood and urine. Before the treatment with penicillamine the urinary concentration of arsenic was 80,0 micrograms/100 ml; 7 days after the onset of treatment the excretion increased to 150.2 micrograms/100 ml. Improvement of the clinical conditions was parallel to these biochemical results.

  12. On the doubly ionized states of Ar2 and their intra- and interatomic decay to Ar23+

    Stoychev, Spas D.; Kuleff, Alexander I.; Tarantelli, Francesco; Cederbaum, Lorenz S.

    2008-01-01

    Potential energy curves of the Auger state Ar + (2p -1 )-Ar, the different one- and two-site dicationic states Ar 2 ++ (with energies in the range of 32-77 eV), and the lowest two-site tricationic states Ar ++ -Ar + (with energies in the range of 64-76 eV) computed using elaborated ab initio methods are reported. The accessible relaxation channels of the electronic states of Ar ++ -Ar populated by Auger decay are studied. In particular, we study in detail the interatomic Coulombic decay following the population of one-site satellite states of Ar ++ (3s -1 3p -1 )-Ar recently observed experimentally. Other relaxation pathways of Ar ++ -Ar, including radiative charge transfer, nuclear dynamics through curve crossing, and intra-atomic decay processes are also investigated

  13. The performance of the INER improved free-air ionization chamber in the comparison of air kerma calibration coefficients for medium-energy X-rays

    Lee, J.-H. E-mail: jhlee@iner.gov.tw; Kotler, L.H.; Bueermann, Ludwig; Hwang, W.-S.; Chiu, J.-H.; Wang, C.-F

    2005-01-01

    This paper describes modifications to an original design, correction factors and uncertainty evaluations for an improved free-air ionization chamber constructed at the Institute of Nuclear Energy Research (INER, Taiwan). In addition, a comparison of secondary standard air kerma calibration coefficients for 100-250 kV medium-energy X-rays was performed to verify the experimental accuracy and measurement consistency of the improved chamber. The comparison results showed a satisfactory agreement in the measurements which were within the combined expanded uncertainties (k=2)

  14. Air kerma national standard of Russian Federation for x-ray and gamma radiation. Activity SSDL/VNIIM in medical radiation dosimetry field

    Kharitonov, I.A.; Villevalde, N.D.; Oborin, A.V.; Fominykh, V.I.

    2002-01-01

    Primary standard of unities air kerma and air kerma rate X-ray and gamma radiation, placed at VNIIM, consists of: plate-parallel free-air ionization chamber IK 10-60 for low-energy X-ray in the generating potential range from 10 to 50 kV; plate-parallel free-air ionization chamber IK 50-400 for medium-energy X-ray in the generating potential range from 50 to 300 kV; cavity cylindrical graphite chambers C1 and C30 with volumes 1 cm 3 and 30 cm 3 for reproduction and transmission the dimensions gamma radiation unities using Cs-137 and Co-60 sources. The next irradiation facilities are used at VNIIM: in low-energy X-ray range: a constant-potential high-voltage generator and a tungsten-anode Xray tube with inherent filtration of around 1 mm Be; in medium-energy X-ray range: set on the basis of an industrial X-ray apparatus Isovolt-400 and a tungsten-anode X-ray tube with inherent filtration of around 3,5 mm Al; in gamma radiations field: units with a radioactive sources Cs-137 with activity 140 and 1200 GBq and Co-60 with activity 120 GBq and irradiation set with a source from Co-60 (activity 3200 GBq). The last one belongs to Central Research Institute for Radiology and Roentgenology (CNIRRI). For measuring currents and charges of standard chambers we use electrometers such as Keithley of model 6517A and B7-45 manufactured by 'Belvar' (Republic Belarus). The reference radiation qualities L, N, H series according to ISO 4037 and the radiation qualities RQR, RQA and RQF according to IEC 61267 for calibration and verification of the therapeutic, diagnostic measurement means are realized in the low-energy and medium-energy X-ray standards. The VNIIM air kerma primary standard of has been participated in the international comparisons: key comparison BIPM.R1(I)-K1 for gamma radiation of Co-60 in 1997; supplementary comparisons BIPM.R1(I)-S10 for gamma radiation of Cs-137 in 1997; key comparison BIPM.R1(I)-K2 for low-energy X-ray range in 1998; key comparison BIPM.R1(I)-K3

  15. Classical treatment of Li2++Ar and He2++Ar collisions

    Jorge, A; Illescas, Clara; Pons, B

    2015-01-01

    Classical Trajectory Monte Carlo calculations are carried out for Li 2+ +Ar and He 2+ +Ar collisions, motivated by recent experiments on these systems. Cross sections for electron capture, projectile electron loss and target multiple ionization processes are evaluated and compared to the experimental values in the 75-500 keV/amy impact energy range. (paper)

  16. A refined astronomically calibrated 40Ar/39Ar age for Fish Canyon sanidine

    Rivera, T.A.; Storey, M.; Zeeden, C.; Hilgen, F.J.; Kuiper, K.

    2011-01-01

    Intercalibration between the astronomical and radio-isotopic dating methods provides a means to improving accuracy and reducing uncertainty of an integrated, multi-chronometer geologic timescale. Here we report a high-precision 40Ar/39Ar age for the FishCanyon sanidine (FCs) neutron fluence monitor,

  17. AR copy number and AR signaling-directed therapies in castration-resistant prostate cancer.

    Salvi, Samanta; Conteduca, Vincenza; Lolli, Cristian; Testoni, Sara; Casadio, Valentina; Zaccheroni, Andrea; Rossi, Lorena; Burgio, Salvatore Luca; Menna, Cecilia; Schepisi, Giuseppe; De Giorgi, Ugo

    2017-11-22

    Adaptive upregulation of androgen receptor (AR) is the most common event involved in the progression from hormone sensitive to castration-resistant prostate cancer (CRPC). AR signaling remains the main target of new AR signalling-directed therapies such as abiraterone and enzalutamide in CRPC patients. In this review, we discuss general mechanisms of resistance to AR-targeted therapies, with a focus on the role of AR copy number (CN). We reported methods and clinical applications of AR CN evaluation in tissue and liquid biopsy, thus to have a complete information regarding its role as predictive and prognostic biomarker. Outcomes of CRPC patients are reported to be highly variable as consequence of tumor heterogeneity. AR CN could contribute to patient selection and tumor monitoring in CRPC treated with new anti-cancer treatment as abiraterone and enzalutamide. Further studies to investigate AR CN effect to these agents and its potential combination with other prognostic or predictive clinical factors are necessary in the context of harmonized clinical trial design. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  18. Support for the Astronomically Calibrated 40Ar/39Ar Age of Fish Canyon Sanidine

    Rivera, Tiffany; Storey, Michael; Zeeden, Christian

    2011-01-01

    al. (2008) determined an astronomically calibrated 40Ar/39Ar age of 28.201 0.046 Ma (2), relative to the indirect astronomically tuned Moroccan Melilla Basin Messâdit section. Here, we provide independent verification for the Kuiper, et al. (2008) FCs age using sanidines extracted from the A1 tephra...

  19. Intercomparison of the air kerma and absorbed dose to water therapy calibrations provided by NRPA and CPRH SSDLs

    Morales, J.A.; Campa, R.; Bjerke, H.; Jensen, H.

    2001-01-01

    in February 2000. The comparison comprised the calibration of a field class ionization chamber in terms of air kerma at low and medium-energy kilo voltage X-ray qualities and 60 Co as well as the calibration in terms of absorbed dose to water (at 60 Co radiation quality). The intercomparison represents for the CPHR the validation of the newly implemented calibration service at X-ray qualities. The NRPA SSDL has in recent years participated in EUROMET and IAEA dosimetry intercomparisons with satisfactory results. Experiences derived from the present comparison are discussed and summarized in this report. Recommendations to the SSDL members of the IAEA/WHO Network in order to encourage regional cooperation by organizing similar intercomparison exercises as well as the possibility for the IAEA to extend the present audit services, to cover certain X-ray beam qualities, are also commented

  20. Baicalein suppresses the androgen receptor (AR)-mediated prostate cancer progression via inhibiting the AR N-C dimerization and AR-coactivators interaction.

    Xu, Defeng; Chen, Qiulu; Liu, Yalin; Wen, Xingqiao

    2017-12-01

    Androgen receptor (AR) plays a critical role in prostate cancer (PCa) development and progression. Androgen deprivation therapy with antiandrogens to reduce androgen biosynthesis or prevent androgens from binding to AR are widely used to suppress AR-mediated PCa growth. However, most of ADT may eventually fail with development of the castration resistance after 12-24 months. Here we found that a natural product baicalein can effectively suppress the PCa progression via targeting the androgen-induced AR transactivation with little effect to AR protein expression. PCa cells including LNCaP, CWR22Rv1, C4-2, PC-3, and DU145, were treated with baicalein and luciferase assay was used to evaluate their effect on the AR transactivation. Cell growth and IC 50 were determined by MTT assay after 48 hrs treatment. RT-PCR was used to evaluate the mRNA levels of AR target genes including PSA, TMPRSS2, and TMEPA1. Western blot was used to determine AR and PSA protein expression. The natural product of baicalein can selectively inhibit AR transactivation with little effect on the other nuclear receptors, including ERα, and GR. At a low concentration, 2.5 μM of baicalein effectively suppresses the growth of AR-positive PCa cells, and has little effect on AR-negative PCa cells. Mechanism dissection suggest that baicalein can suppress AR target genes (PSA, TMPRSS2, and TMEPA1) expression in both androgen responsive LNCaP cells and castration resistant CWR22Rv1 cells, that may involve the inhibiting the AR N/C dimerization and AR-coactivators interaction. Baicalein may be developed as an effective anti-AR therapy via its ability to inhibit AR transactivation and AR-mediated PCa cell growth.

  1. Ar-41 measurements and nuclear emergency preparedness

    Kunst, J.J.; Rodriguez, M.; Ugarte, R.; Vigile, R.S.; Boutet, L.I.; Jordan, O.D.; Hernandez, D.G.

    2010-01-01

    During the early phase of an emergency is necessary to confirm the release of radioactivity predictions made by the operator of the nuclear plant. In this context, it has begun measuring Ar-41 in the vicinity of a research reactor. Since the Ar-41 is produced in the reactor, it has been studied as a good way to validate the air dispersion model used in nuclear emergencies and to develop a method to improve the characterization of the release. For this latter purpose a pilot experiment was conducted to determine computational and experimental methods, the flux of 1.29 MeV of Ar-41 and compared to evaluate the accuracy of the assessments made. This paper describes meteorological forecasting systems used in the experiment, the estimate of the stability class and the concentration of nuclides using a calculation code developed by the ARN, as well as the methodology and equipment used for measurement in the field. (authors) [es

  2. Arsenic exposure assessment of children living in a lead mining area in Southeastern Brazil Avaliação da exposição de crianças ao arsênio em área de mineração de chumbo na Região Sudeste do Brasil

    Alice Momoyo Sakuma

    2010-02-01

    Full Text Available Environmental contamination by arsenic compounds in the Ribeira River Valley, São Paulo, Brazil has already been observed. Lead mining and refining activities had been carried on since late colonial times and finished recently, at the end of 1995. The source of As in the region is known to be mainly from arsenopirite geological presence in the lead ore. Chronic exposure to arsenic compounds may cause peripheral vascular disorders, hyperpigmentation, hiperkeratosis and cancer of the skin, bladder, lung, liver and other internal organs. The purpose of this study was to assess children exposure to arsenic from environmental sources in the region. Urine samples from children between 7 to 14 years old were collected at the following localities: Cerro Azul (Paraná; urban areas of Ribeira (São Paulo and Adrianópolis (Paraná; Vila Mota neighborhood (rural area of Adrianópolis and Serra neighborhood (Iporanga, São Paulo, identified as groups 1, 2, 3 and 4, respectively. Group 1 was considered as non-exposed control group. Toxicologically relevant forms of As were determined by atomic absorption spectrometry with hydride generation system. The median values of urine arsenic levels obtained in groups 1, 2, 3 and 4 were respectively: 3.60, 6.30, 6.41 e 8.94μg/L.Contaminação ambiental por compostos de arsênio no Vale do Ribeira, São Paulo, Brasil, tem sido já observada. As atividades de mineração e refinamento do chumbo têm ocorrido desde a época colonial e foram encerradas recentemente, no final de 1995. A principal fonte de arsênio na região é arsenopirita que ocorre geologicamente no minério de chumbo. Exposição crônica aos compostos de arsênio podem causar desordens vasculares periféricas, hiperpigmentação, hiperqueratose, além de câncer de pele, bexiga, pulmão, fígado e outros órgãos. O objetivo do presente estudo foi avaliar a exposição de crianças ao arsênio proveniente de fontes ambientais na região. Amostras de

  3. AR(p) -based detrended fluctuation analysis

    Alvarez-Ramirez, J.; Rodriguez, E.

    2018-07-01

    Autoregressive models are commonly used for modeling time-series from nature, economics and finance. This work explored simple autoregressive AR(p) models to remove long-term trends in detrended fluctuation analysis (DFA). Crude oil prices and bitcoin exchange rate were considered, with the former corresponding to a mature market and the latter to an emergent market. Results showed that AR(p) -based DFA performs similar to traditional DFA. However, the former DFA provides information on stability of long-term trends, which is valuable for understanding and quantifying the dynamics of complex time series from financial systems.

  4. Geology, geochemistry and {sup 40}K-{sup 40}Ar geochronometry of Miocene magmatism in Algiers area, Northern Algeria; La magmatisme miocene de l`Est Algerois, geologie, geochimie et geochronologie {sup 40}K-{sup 40}Ar

    Belanteur, O; Ouabadi, A; Semroud, B; Megartsi, M H [Algiers Univ. (Algeria). Faculte des Sciences; Bellon, H; Maury, R C; Coutelle, A [Brest Univ., 29 (France); Fourcade, S [Rennes-1 Univ., 35 (France)

    1996-12-31

    Miocene magmatic rocks outcrop within a narrow coastal strip east of Algiers. They include basaltic and andesitic lava flows and intrusions (Dellys, Cap Djinet), the Thenia granodioritic plug and the dacitic to rhyolitic lavas and pyroclastic flows from Zemmouri El Bahri and El Kerma. Despite the effects of hydrothermal alteration, {sup 40}K-{sup 40}Ar ages coupled with micropalaeontological data lead to recognition of two emplacement events at 16-15 and 14-12 Ma, respectively. All the studied calc-alkaline to potassic calc-alkaline rocks are enriched in highly incompatible elements and display negative Nb anomalies. Acid magmas have a pronounced crustal imprint ({sup 87}Sr{sup 86}Sr{sub i} =3D 0.7082 to 0.7155; {delta}{sup 18}O =3D +9 to +13 per mill) which together with La/Nb ratios argues for the occurrence of upper crustal contamination processes. However, the Nb-depletion of the associated basalts suggest that the studied magmas derive from a mantle source which underwent subduction-related metasomatic enrichments prior to their Miocene emplacement. (authors). 13 refs., 3 figs., 2 tabs.

  5. Evaluation of cross sections and calculation of kerma factors for neutrons up to 80 MeV on {sup 12}C

    Harada, M.; Watanabe, Y. [Kyushu Univ., Fukuoka (Japan); Chiba, S.; Fukahori, T.

    1997-03-01

    We have evaluated the cross sections for neutrons with incident energies from 20 to 80 MeV on {sup 12}C for the JENDL high-energy file. The total cross sections were determined by a generalized least-squares method with available experimental data. The cross sections of elastic and inelastic scattering to the first 2{sup +} were evaluated with the theoretical calculations. The optical potentials necessary for these calculations were derived using a microscopic approach by Jeukenne-Lejeune-Mahaux. For the evaluation of double differential emission cross sections (DDXs), we have developed a code system SCINFUL/DDX in which total 35 reactions including the 3-body simultaneous breakup process (n+{sup 12}C {yields} n+{alpha}+{sup 8}Be) can be taken into consideration in terms of a Monte Carlo method, and have calculated the DDXs of all light-emissions (A{<=}4) and heavier reaction products. The results for protons, deuterons, and alphas showed overall good agreement with experimental data. The code is also applicable for calculations of total and partial kerma factors. Total kerma factors calculated for energies from 20 to 80 MeV were compared with the measurements and the other latest evaluations from the viewpoints of medical application and nuclear heating estimation. (author)

  6. Comparisons of the standards for air kerma of the PTB and the BIPM for 60Co and 137Cs gamma radiation

    Allisy-Roberts, P.J.; Burns, D.T.; Buermann, L.; Kramer, H.M.

    2005-11-01

    Direct comparisons of the standards for air kerma of the Physikalisch-Technische Bundesanstalt (PTB, Germany) and of the Bureau International des Poids et Mesures (BIPM) were carried out in the 60 Co and 137 Cs radiation beams of the BIPM in 2000. The results, expressed as ratios of the PTB and the BIPM standards for air kerma, indicate a relative difference in 60 Co of 9.9 x 10 -3 with a combined standard uncertainty of 1.8 x 10 -3 , and in 137 Cs of 6.4 x 10 -3 with a combined standard uncertainty of 2.8 x 10 -3 . The earlier comparisons in 60 Co γ rays made in 1971 (direct) and 1989 (indirect) resulted in an agreement of the two standards within 2 x 10 -3 . The differences obtained now are due to the application of new correction factors for wall effects and point source non-uniformity of the beam, k wall and k pn , for the PTB standards, which were calculated using Monte Carlo methods. (authors)

  7. Air kerma standard for calibration of well-type chambers in Brazil using {sup 192}Ir HDR sources and its traceability

    Di Prinzio, Renato; Almeida, Carlos Eduardo de [Laboratorio de Ciencias Radiologicas-Universidade do Estado do Rio de Janeiro (LCR/UERJ), R. Sao Francisco Xavier, 524, Pavilhao Haroldo Lisboa da Cunha, Terreo, Sala 136-Maracana, CEP 20550-900-Rio de Janeiro/RJ-Rio de Janeiro, RJ (Brazil) and Instituto de Radioprotecao e Dosimetria-Comissao Nacional de Energia Nuclear (IRD/CNEN), Av. Salvador Allende, s/n, Jacarepagua-CE22780-160-Rio de Janeiro, RJ (Brazil); Laboratorio de Ciencias Radiologicas-Universidade do Estado do Rio de Janeiro (LCR/UERJ), R. Sao Francisco Xavier, 524, Pavilhao Haroldo Lisboa da Cunha, Terreo, Sala 136-Maracana, CEP 20550-900-Rio de Janeiro/RJ-Rio de Janeiro, RJ (Brazil)

    2009-03-15

    In Brazil there are over 100 high dose rate (HDR) brachytherapy facilities using well-type chambers for the determination of the air kerma rate of {sup 192}Ir sources. This paper presents the methodology developed and extensively tested by the Laboratorio de Ciencias Radiologicas (LCR) and presently in use to calibrate those types of chambers. The system was initially used to calibrate six well-type chambers of brachytherapy services, and the maximum deviation of only 1.0% was observed between the calibration coefficients obtained and the ones in the calibration certificate provided by the UWADCL. In addition to its traceability to the Brazilian National Standards, the whole system was taken to University of Wisconsin Accredited Dosimetry Calibration Laboratory (UWADCL) for a direct comparison and the same formalism to calculate the air kerma was used. The comparison results between the two laboratories show an agreement of 0.9% for the calibration coefficients. Three Brazilian well-type chambers were calibrated at the UWADCL, and by LCR, in Brazil, using the developed system and a clinical HDR machine. The results of the calibration of three well chambers have shown an agreement better than 1.0%. Uncertainty analyses involving the measurements made both at the UWADCL and LCR laboratories are discussed.

  8. Evaluation of Wall Correction Factor of INER's Air-Kerma Primary Standard Chamber and Dose Variation by Source Displacement for HDR 192Ir Brachytherapy

    J. H. Lee

    2013-01-01

    Full Text Available The aim of the present study was to estimate the wall effect of the self-made spherical graphite-walled cavity chamber with the Monte Carlo method for establishing the air-kerma primary standard of high-dose-rate (HDR 192Ir brachytherapy sources at the Institute of Nuclear Energy Research (INER, Taiwan. The Monte Carlo method established in this paper was also employed to respectively simulate wall correction factors of the 192Ir air-kerma standard chambers used at the National Institute of Standards and Technology (NIST, USA and the National Physical Laboratory (NPL, UK for comparisons and verification. The chamber wall correction calculation results will be incorporated into INER's HDR 192Ir primary standard in the future. For the brachytherapy treatment in the esophagus or in the bronchi, the position of the isotope may have displacement in the cavity. Thus the delivered dose would differ from the prescribed dose in the treatment plan. We also tried assessing dose distribution due to the position displacement of HDR 192Ir brachytherapy source in a phantom with a central cavity by the Monte Carlo method. The calculated results could offer a clinical reference for the brachytherapy within the human organs with cavity.

  9. Key comparison BIPM.RI(I)-K1 of the air-kerma standards of the MKEH, Hungary and the BIPM in 60Co gamma radiation

    Kessler, C.; Burns, D.; Machula, G.

    2018-01-01

    A comparison of the standards for air kerma of the Hungarian Trade Licensing Office (MKEH), Hungary and of the Bureau International des Poids et Mesures (BIPM) was carried out in the 60Co radiation beam of the BIPM in March 2016. The comparison result, evaluated as a ratio of the MKEH and the BIPM standards for air kerma, is 1.0047 with a combined standard uncertainty of 1.9 × 10-3. The results for an indirect comparison made at the same time are consistent with the direct results at the level of 2.6 parts in 103. The results are analysed and presented in terms of degrees of equivalence, suitable for entry in the BIPM key comparison database. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  10. Computational tool kit for evaluating air kerma with the purpose of radiation protection of hospital inpatients: proposal of a simple experimental evaluation method

    Hoff, Gabriela; Fischer, Andreia Caroline Fischer da Silveira, E-mail: ghoff.gesic@gmail.com [Pontificia Universidade Catolica do Rio Grande do Sul (PUCRS), Porto Alegre, RS, (Brazil); Andrade, Jose Rodrigo Mendes; Bacelar, Alexandre [Service of Medical Physics and Radioprotection, Hospital de Clinicas de Porto Alegre (HCPA), Porto Alegre, RS (Brazil)

    2012-03-15

    Objective: To present a data analysis toolkit that may be utilized with the purpose of radiation protection of hospital inpatients and workers in areas where mobile apparatuses are used. Materials and methods: an Excel Active Sheet was utilized to develop a computational toolkit with exposure measurements to generate a database of shape factors and to calculate the air kerma around hospital beds. The initial database included data collected with three mobile apparatuses. A non-anthropomorphic phantom was utilized and exposure measurements were performed on a (4.2 x 4.2) m{sup 2} mesh-grid at 0.3 m steps. Results: The toolkit calculates the air kerma (associated with patients' radiation exposure and with ambient equivalent dose) under secondary radiation. For distances lower than 60.0 cm, values above the maximum ambient equivalent dose threshold defined for radiation free areas (0.5 mSv/year) were verified. Data collected at 2.1 m have always presented values lower than 12% of that threshold. Conclusion: The toolkit can aid in the radiological protection of patients and workers, provided it is combined with appropriate data collection, since it allows the determination of radiation free areas around beds in rooms where mobile X-ray apparatuses are utilized. (author)

  11. Computational tool kit for evaluating air kerma with the purpose of radiation protection of hospital inpatients: proposal of a simple experimental evaluation method

    Hoff, Gabriela; Fischer, Andreia Caroline Fischer da Silveira; Andrade, Jose Rodrigo Mendes; Bacelar, Alexandre

    2012-01-01

    Objective: To present a data analysis toolkit that may be utilized with the purpose of radiation protection of hospital inpatients and workers in areas where mobile apparatuses are used. Materials and methods: an Excel Active Sheet was utilized to develop a computational toolkit with exposure measurements to generate a database of shape factors and to calculate the air kerma around hospital beds. The initial database included data collected with three mobile apparatuses. A non-anthropomorphic phantom was utilized and exposure measurements were performed on a (4.2 x 4.2) m 2 mesh-grid at 0.3 m steps. Results: The toolkit calculates the air kerma (associated with patients' radiation exposure and with ambient equivalent dose) under secondary radiation. For distances lower than 60.0 cm, values above the maximum ambient equivalent dose threshold defined for radiation free areas (0.5 mSv/year) were verified. Data collected at 2.1 m have always presented values lower than 12% of that threshold. Conclusion: The toolkit can aid in the radiological protection of patients and workers, provided it is combined with appropriate data collection, since it allows the determination of radiation free areas around beds in rooms where mobile X-ray apparatuses are utilized. (author)

  12. Efeitos da temperatura e da movimentação do ar sobre o isolamento térmico do velo de ovinos em câmara climática Effect of temperature and air velocity on the thermal insulation of the fleece of sheep in climatic chamber

    Alex Sandro Campos Maia

    2009-01-01

    Full Text Available Foram utilizados dez ovinos da raça Corriedale - cinco machos e cinco fêmeas com pesos entre 52,2 e 87,6 kg - com o objetivo de avaliar o efeito da combinação da movimentação do ar (0 e 5,0 m/s com a temperatura do ar (25, 30 e 40ºC sobre a temperatura retal (T R, ºC, da epiderme (T E, ºC, da superfície do velo (T V, ºC e do interior do velo (T I, ºC e a espessura do velo (E V, cm e suas relações com o isolamento térmico do velo. A presença de vento não teve efeito sobre as variáveis estudadas, o que sugere que fluxo de ar (40ºC o fluxo de calor sensível não foi significativa.Ten Corriedale sheep were evaluated, five males and five females with 52.2 to 87.6 kg of body weight, to evaluate the effect of air velocity (0 and 5 m/s and temperature (25, 30 and 40ºC on rectal temperature (T R, ºC, skin temperature (T E, ºC, fleece surface temperature (T V, ºC, temperature inside the fleece (T I, ºC, and fleece thickness (E V, cm and their relationship with fleece thermal insulation. The results showed that air velocity did not affect the studied traits, suggesting that airflow 40°C, the sensible heat flow was not significant.

  13. 40Ar/36Ar in MORB glasses: Constraints on atmosphere and mantle evolution

    Sarda, P.; Staudacher, T.; Allegre, C.J.; Paris-7 Univ., 75

    1985-01-01

    Argon isotopic composition measurements of MORB glassy samples from the Pacific, Atlantic and Indian Oceans are performed. There is a very large scatter in the 40 Ar/ 36 Ar ratio, from 980 up to 24,400 for bulk rock analyses, which is mainly due to atmospheric contamination: Using the stepwise heating technique, very high ratios are obtained, from 15,000 up to 25,250 which is the highest 40 Ar/ 36 Ar ratio ever measured in MORB. We establish a negative correlation between the highest 40 Ar/ 36 Ar results from stepwise heating and 87 Sr/ 86 Sr ratios, which is perfectly consistent with a two-layered mantle structure. From both 40 Ar and 129 Xe MORB systematics a model is proposed for the kinetics of degassing: a very early and extensive burst, with a time constant of approx.= 4 My, is followed by a slower process of present day type, with a time constant of approx.= 0.5 Gy. The mean age of the atmosphere is so determined to be around 4.4 Gy. (orig./WB)

  14. OCORRÊNCIA E DURAÇÃO DAS TEMPERATURAS MÍNIMAS DIÁRIAS DO AR PREJUDICIAIS À FECUNDAÇÃO DAS FLORES DO ARROZ EM SANTA MARIA. RS. III: PROBABILIDADES DE OCORRÊNCIA DA DURAÇÃO DAS TEMPERATURAS BAIXAS

    Flávio Miguel Schneider

    1992-04-01

    Full Text Available Utilizando os valores das temperaturas mínimas, máximas e das 21 h, hora local, dos meses de dezembro, janeiro, fevereiro e março registradas na Estação Climatológica Principal de Santa Maria, RS, determinaram-se as probabilidades de ocorrência da duração máxima de horas com temperatura do ar ≤ 10, 11, 12, 13, 14, 15, 16 e 17,0°C e de seqüências de dias consecutivos com no mínimo uma hora de duração com temperatura do ar ≤ 15, 16 e 17,0°C. Essas probabilidades foram obtidas para cada decêndio dos meses estudados. Os resultados evidenciam que o risco de ocorrência de temperaturas prejudiciais à fecundação das flores da cultura do arroz é bem menor no 2° e 3° decêndio do mês de fevereiro. Deve-se, portanto, semear e/ou escolher ciclo de cultivar de arroz que possibilite que a fase de floração ocorra durante o 2° e 3° decêndio do mês de fevereiro.

  15. Electron impact ionization of Ar8+

    Defrance, P.; Rachafi, S.; Jureta, J.; Meyer, F.; Chantrenne, S.

    1986-01-01

    Absolute electron impact ionization cross-sections have been measured for the Neon-like Ar 8+ in the energy range from below the threshold for the metastable state to 2500 eV. No contribution of metastable states is observed. The results are well reproduced by the Distorted Wave Born Approximation. 12 refs., 1 fig

  16. 75 FR 7637 - Arkansas Disaster #AR-00040

    2010-02-22

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12031 and 12032] Arkansas Disaster AR-00040 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster for the State of Arkansas dated 02/10/2010. Incident: Severe Storms and...

  17. 76 FR 42155 - Arkansas Disaster #AR-00051

    2011-07-18

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12680 and 12681] Arkansas Disaster AR-00051 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the State of Arkansas (FEMA- 4000-DR), dated 07...

  18. 75 FR 7636 - Arkansas Disaster #AR-00042

    2010-02-22

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12034 and 12035] Arkansas Disaster AR-00042 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the State of Arkansas (FEMA-- 1872--DR), dated...

  19. 76 FR 42154 - Arkansas Disaster #AR-00050

    2011-07-18

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12678 and 12679] Arkansas Disaster AR-00050 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for the State of Arkansas (FEMA-4000-DR), dated 07/08/2011. Incident: Severe...

  20. 75 FR 30872 - Arkansas Disaster # AR-00043

    2010-06-02

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12196 and 12197] Arkansas Disaster AR-00043 AGENCY: U.S. Small Business Administration. ACTION: Notice SUMMARY: This is a notice of an Administrative declaration of a disaster for the State of Arkansas dated 05/26/2010. Incident: Severe storms, tornadoes and...

  1. 78 FR 39821 - Arkansas Disaster #AR-00064

    2013-07-02

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 13637 and 13638] Arkansas Disaster AR-00064 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the State of Arkansas (FEMA- 4124-DR), dated 06...

  2. 76 FR 27140 - Arkansas Disaster # AR-00049

    2011-05-10

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12562 and 12563] Arkansas Disaster AR-00049 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the State of Arkansas (FEMA- 1975-DR), dated 05...

  3. 78 FR 9448 - Arkansas Disaster #AR-00061

    2013-02-08

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 13473 and 13474] Arkansas Disaster AR-00061 AGENCY: U.S. Small Business Administration. ACTION: Notice SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the State of Arkansas (FEMA- 4100-DR), dated 01...

  4. 76 FR 27139 - Arkansas Disaster #AR-00048

    2011-05-10

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12560 and 12561] Arkansas Disaster AR-00048 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for the State of Arkansas (FEMA-1975-DR), dated 05/02/2011. Incident: Severe...

  5. "ARS 01", perspektiivide avamine / Helen Kivisoo

    Kivisoo, Helen

    2001-01-01

    30. IX 2001-20. I 2002 Kiasmas kuuendat korda toimuvast rahvusvahelisest näitusest "ARS", kus Eestist osaleb Marko Mäetamm. Kuraatorid Tuula Arkio, Maaretta Jaukkuri, Patrik Nyberg, Jari-Pekka Vanhala. Teemaks "kolmas ruum". Näituse kajastamisest.

  6. Hazard evaluation for 244-AR vault facility

    BRAUN, D.J.

    1999-01-01

    This document presents the results of a hazard identification and evaluation performed on the 244-AR Vault Facility to close a USQ (USQ No. TF-98-0785, Potential Inadequacy in Authorization Basis (PIAB): To Evaluate Miscellaneous Facilities Listed in HNF-2503 And Not Addressed In The TWRS Authorization Basis) that was generated as part of an evaluation of inactive TWRS facilities

  7. A compilation of {sup 40}Ar-{sup 39} and K-Ar ages: report 25

    Hunt, P A [Geological Survey of Canada, Ottawa, ON (Canada); Roddick, J C

    1997-12-31

    Twenty-three {sup 40}Ar-{sup 39}Ar age determinations (including two potassium-argon analyses) carried out by the Geological Survey of Canada are reported. Each age determination is accompanied by a description of the rock and mineral concentrate used; brief interpretative comments regarding the geological significance of each age are also provided where possible. The experimental procedures employed are described in outline. An index of all Geological Survey of Canada K-Ar age determinations published in this format has been prepared using NTS quadrangles as the primary reference. (author). 6 refs., 2 tabs., 1 fig.

  8. A compilation of 40Ar-39 and K-Ar ages: report 25

    Hunt, P.A.; Roddick, J.C.

    1996-01-01

    Twenty-three 40 Ar- 39 Ar age determinations (including two potassium-argon analyses) carried out by the Geological Survey of Canada are reported. Each age determination is accompanied by a description of the rock and mineral concentrate used; brief interpretative comments regarding the geological significance of each age are also provided where possible. The experimental procedures employed are described in outline. An index of all Geological Survey of Canada K-Ar age determinations published in this format has been prepared using NTS quadrangles as the primary reference. (author). 6 refs., 2 tabs., 1 fig

  9. The ChArMEx database

    Ferré, Hélène; Belmahfoud, Nizar; Boichard, Jean-Luc; Brissebrat, Guillaume; Cloché, Sophie; Descloitres, Jacques; Fleury, Laurence; Focsa, Loredana; Henriot, Nicolas; Mière, Arnaud; Ramage, Karim; Vermeulen, Anne; Boulanger, Damien

    2015-04-01

    The Chemistry-Aerosol Mediterranean Experiment (ChArMEx, http://charmex.lsce.ipsl.fr/) aims at a scientific assessment of the present and future state of the atmospheric environment in the Mediterranean Basin, and of its impacts on the regional climate, air quality, and marine biogeochemistry. The project includes long term monitoring of environmental parameters , intensive field campaigns, use of satellite data and modelling studies. Therefore ChARMEx scientists produce and need to access a wide diversity of data. In this context, the objective of the database task is to organize data management, distribution system and services, such as facilitating the exchange of information and stimulating the collaboration between researchers within the ChArMEx community, and beyond. The database relies on a strong collaboration between ICARE, IPSL and OMP data centers and has been set up in the framework of the Mediterranean Integrated Studies at Regional And Locals Scales (MISTRALS) program data portal. ChArMEx data, either produced or used by the project, are documented and accessible through the database website: http://mistrals.sedoo.fr/ChArMEx. The website offers the usual but user-friendly functionalities: data catalog, user registration procedure, search tool to select and access data... The metadata (data description) are standardized, and comply with international standards (ISO 19115-19139; INSPIRE European Directive; Global Change Master Directory Thesaurus). A Digital Object Identifier (DOI) assignement procedure allows to automatically register the datasets, in order to make them easier to access, cite, reuse and verify. At present, the ChArMEx database contains about 120 datasets, including more than 80 in situ datasets (2012, 2013 and 2014 summer campaigns, background monitoring station of Ersa...), 25 model output sets (dust model intercomparison, MEDCORDEX scenarios...), a high resolution emission inventory over the Mediterranean... Many in situ datasets

  10. VLA radio observations of AR Scorpii

    Stanway, E. R.; Marsh, T. R.; Chote, P.; Gänsicke, B. T.; Steeghs, D.; Wheatley, P. J.

    2018-03-01

    Aims: AR Scorpii is unique amongst known white dwarf binaries in showing powerful pulsations extending to radio frequencies. Here we aim to investigate the multi-frequency radio emission of AR Sco in detail, in order to constrain its origin and emission mechanisms. Methods: We present interferometric radio frequency imaging of AR Sco at 1.5, 5 and 9 GHz, analysing the total flux and polarization behaviour of this source at high time resolution (10, 3 and 3 s), across a full 3.6 h orbital period in each band. Results: We find strong modulation of the radio flux on the orbital period and the orbital sideband of the white dwarf's spin period (also known as the "beat" period). This indicates that, like the optical flux, the radio flux arises predominantly from on or near the inner surface of the M-dwarf companion star. The beat-phase pulsations of AR Sco decrease in strength with decreasing frequency. They are strongest at 9 GHz and at an orbital phase 0.5. Unlike the optical emission from this source, radio emission from AR Sco shows weak linear polarization but very strong circular polarization, reaching 30% at an orbital phase 0.8. We infer the probable existence of a non-relativistic cyclotron emission component, which dominates at low radio frequencies. Given the required magnetic fields, this also likely arises from on or near the M-dwarf. A table of the flux time series is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/611/A66

  11. Intercomparison of absorbed dose to water and air-kerma based dosimetry protocols for photon and electron beams

    Huq, M.S.

    2002-01-01

    Full text: During the last three decades the International Atomic Energy Agency (IAEA), the American Association of Physicists in Medicine (AAPM) and organizations from various countries have published Codes of Practice (CoP) and dosimetry protocols for the calibration of high-energy photon and electron beams. They are based on the air-kerma or exposure calibration factor of an ionization chamber in a 60 Co gamma ray beam and formalism for the determination of absorbed dose to water in reference conditions. In recent years, the IAEA (IAEA TRS-398) and the AAPM (AAPM TG-51) have published new external beam dosimetry protocols that are based on the use of an ionization chamber calibrated in terms of absorbed dose to water in a standards laboratory's reference quality beam. These two new protocols follow those by the German Standard DIN, the British IPSM and the IAEA CoP for plane-parallel chambers, which have discussed and implemented the procedures for the determination of absorbed dose-to-water based on standards of absorbed dose-to-water. Since the publication of these protocols and CoPs, many comparisons, theoretical as well as experimental, between them have been published in the literature providing valuable information about the sources of similarities and discrepancies that exist among them. For example, the differences in the basic data for photon and electron beams included in the various IAEA CoPs are very small for the second edition of TRS-277 for photons, TRS-381 for electrons and TRS-398. In these cases the data changes posed by the adoption of TRS-398 are within about ±0.3% for the most commonly used energies. When implementing TRS-398 in these cases, the main difference will arise from the transition from K air to D w standards. For example, experimental comparison of absorbed doses between TRS-398 and TRS-277 for photons show an average difference of about 0.3% for most commonly used energies with a maximum difference of about 1% at a TPR 20

  12. /sup 40/Ar//sup 39/Ar and K-Ar dating of altered glassy volcanic rocks: the Dabi Volcanics, P. N. G

    Walker, D.A. (Australian National Univ., Canberra. Dept. of Geology); McDougall, I. (Australian National Univ., Canberra. Research School of Earth Sciences)

    1982-11-01

    K-Ar and /sup 40/Ar//sup 39/Ar ages have been determined for altered submarine tholeiitic and boninite (high-Mg andesite) lavas from the Dabi Volcanics, Cape Vogel Peninsula, Papua New Guinea. /sup 40/Ar//sup 39/Ar whole rock total fusion and plateau ages identify a Late Paleocene age for the tholeiitic lavas (58.9 +- 1.1 Ma), and also for the boninitic lavas (58.8 +- 0.8 Ma). Apparent K-Ar ages for the same samples range from 27.2 +- 0.7 to 63.9 +- 4.5 Ma, and young K-Ar ages for glassy boninites are probably due to variable radiogenic /sup 40/Ar(/sup 40/Ar*) loss. These new ages effectively reconcile previously ambiguous age data for the Dabi Volcanics, and indicate contemporaneous tholeiitic and boninitic volcanism occurring in southeast PNG during the Late Paleocene. Smectites, developed as alteration products after glass in oceanic lavas commonly do not retain /sup 39/Ar during or subsequent to irradiation, but in some cases may contain /sup 40/Ar*. The results are discussed.

  13. 40Ar/39Ar and K-Ar dating of altered glassy volcanic rocks: the Dabi Volcanics, P.N.G

    Walker, D.A.; McDougall, I.

    1982-01-01

    K-Ar and 40 Ar/ 39 Ar ages have been determined for altered submarine tholeiitic and boninite (high-Mg andesite) lavas from the Dabi Volcanics, Cape Vogel Peninsula, Papua New Guinea. 40 Ar/ 39 Ar whole rock total fusion and plateau ages identify a Late Paleocene age for the tholeiitic lavas (58.9 +- 1.1 Ma), and also for the boninitic lavas (58.8 +- 0.8 Ma). Apparent K-Ar ages for the same samples range from 27.2 +- 0.7 to 63.9 +- 4.5 Ma, and young K-Ar ages for glassy boninites are probably due to variable radiogenic 40 Ar( 40 Ar*) loss. These new ages effectively reconcile previously ambiguous age data for the Dabi Volcanics, and indicate contemporaneous tholeiitic and boninitic volcanism occurring in southeast PNG during the Late Paleocene. Smectites, developed as alteration products after glass in oceanic lavas commonly do not retain 39 Ar during or subsequent to irradiation, but in some cases may contain 40 Ar*. The results are discussed. (author)

  14. A Refined Astronomically Calibrated 40Ar/39Ar Age for Fish Canyon Sanidine

    Rivera, Tiffany; Storey, Michael; Zeeden, Christian

    2011-01-01

    Intercalibration between the astronomical and radio-isotopic dating methods provides a means to improving accuracy and reducing uncertainty of an integrated, multi-chronometer geologic timescale. Here we report a high-precision 40Ar/39Ar age for the Fish Canyon sanidine (FCs) neutron fluence...... sanidine age of 0.7674±0.0022 Ma (2σ, external errors) is indistinguishable from the ID-TIMS U/Pb zircon age (0.7671±0.0019 Ma). The consistency between the astronomically calibrated 40Ar/39Ar sanidine age and U/Pb zircon age for this Quaternary unit suggests that agreement between these two radio-isotopic...... dating techniques is now achievable at better than±0.3% (2σ) in the youngest part of geologic time (

  15. 40Ar-39Ar age studies for tectonics of the Gondwana land

    Takigami, Yutaka; Sugiura, Naoji.

    1997-01-01

    40 Ar- 39 Ar age studies have been performed for samples from Antarctica and India which were parts of the Gondwana land at Mesozoic and Paleozoic time in order to investigate their thermal history and tectonic movement. From the both areas, ages of about 500 Ma which have been considered to be the age of Pan-African Orogeny were obtained, which represents that this thermal event spread widely over the Gondwana land. (author)

  16. Single grains, thermal histories, and the 40Ar/39Ar method

    Wright, Norrie

    1989-01-01

    A key part in unraveling the history of the physical evolution of the earth is knowledge of the earth's thermal history. 40 Ar/ 39 Ar step heating of mineral samples provides a means of defining a local thermal history. to do this accurately the challenge is to extract meaningful diffusion parameters from a mineral's Arrhenius plot. In the case of biotite single grains, where the laboratory release of argon is a complex process, this can be a difficult task. (12 refs., 5 figs.)

  17. ^<40>Ar-^<39>Ar Age Studies for Tectonics of the Gondwana Land

    Takigami, Yutaka; Sugiura, Naoji

    1997-01-01

    ^Ar-^Ar age studies have been performed for samples from Antarctica and India which were parts of the Gondwana land at Mesozoic and Paleozoic time in order to investigate their thermal history and tectonic movement. From the both areas, ages of about 500 Ma which have been considered to be the age of Pan-African Orogeny were obtained, which represents that this thermal event spread widely over the Gondwana land.

  18. Effects of Sorafenib on <em>C>-Terminally Truncated Androgen Receptor Variants in Human Prostate Cancer Cells

    Mark Schrader

    2012-09-01

    Full Text Available Recent evidence suggests that the development of castration resistant prostate cancer (CRPCa is commonly associated with an aberrant, ligand-independent activation of the androgen receptor (AR. A putative mechanism allowing prostate cancer (PCa cells to grow under low levels of androgens, is the expression of constitutively active, <em>C>-terminally truncated AR lacking the AR-ligand binding domain (LBD. Due to the absence of a LBD, these receptors, termed ARΔLBD, are unable to respond to any form of anti-hormonal therapies. In this study we demonstrate that the multikinase inhibitor sorafenib inhibits AR as well as ARΔLBD-signalling in CRPCa cells. This inhibition was paralleled by proteasomal degradation of the AR- and ARΔLBD-molecules. In line with these observations, maximal antiproliferative effects of sorafenib were achieved in AR and ARΔLBD-positive PCa cells. The present findings warrant further investigations on sorafenib as an option for the treatment of advanced AR-positive PCa.

  19. Average glandular dose in paired digital mammography and digital breast tomosynthesis acquisitions in a population based screening program: effects of measuring breast density, air kerma and beam quality

    Helge Østerås, Bjørn; Skaane, Per; Gullien, Randi; Catrine Trægde Martinsen, Anne

    2018-02-01

    The main purpose was to compare average glandular dose (AGD) for same-compression digital mammography (DM) and digital breast tomosynthesis (DBT) acquisitions in a population based screening program, with and without breast density stratification, as determined by automatically calculated breast density (Quantra™). Secondary, to compare AGD estimates based on measured breast density, air kerma and half value layer (HVL) to DICOM metadata based estimates. AGD was estimated for 3819 women participating in the screening trial. All received craniocaudal and mediolateral oblique views of each breasts with paired DM and DBT acquisitions. Exposure parameters were extracted from DICOM metadata. Air kerma and HVL were measured for all beam qualities used to acquire the mammograms. Volumetric breast density was estimated using Quantra™. AGD was estimated using the Dance model. AGD reported directly from the DICOM metadata was also assessed. Mean AGD was 1.74 and 2.10 mGy for DM and DBT, respectively. Mean DBT/DM AGD ratio was 1.24. For fatty breasts: mean AGD was 1.74 and 2.27 mGy for DM and DBT, respectively. For dense breasts: mean AGD was 1.73 and 1.79 mGy, for DM and DBT, respectively. For breasts of similar thickness, dense breasts had higher AGD for DM and similar AGD for DBT. The DBT/DM dose ratio was substantially lower for dense compared to fatty breasts (1.08 versus 1.33). The average c-factor was 1.16. Using previously published polynomials to estimate glandularity from thickness underestimated the c-factor by 5.9% on average. Mean AGD error between estimates based on measurements (air kerma and HVL) versus DICOM header data was 3.8%, but for one mammography unit as high as 7.9%. Mean error of using the AGD value reported in the DICOM header was 10.7 and 13.3%, respectively. Thus, measurement of breast density, radiation dose and beam quality can substantially affect AGD estimates.

  20. Influence of secondary packing on the freezing time of chiken meat in air blast freezing tunnels Influência da embalagem secundária sobre o tempo de congelamento de carne de frango em túneis de circulação de ar forçada

    Clarice de Ávila Santos

    2008-12-01

    Full Text Available Freezing of poultry cuts in continuous convective air blast tunnels is normally performed with the products protected by Low Density Polyethylene (LDPE as a primary packaging and using Corrugated Cardboard Boxes (CCB as secondary packaging. The objective of this work was to investigate the influence of these secondary packaging on the freezing of poultry cuts in continuous convective air blast tunnels. The study was performed by replacing CCB with Perforated Metal Boxes (PMB in order to remove the packaging thermal resistance. The assays, performed in a industrial plant, demonstrated that CCB used commercially for meat freezing have a high heat transfer resistance. Their replacement with PMB can lead to shorter freezing times and spatially homogeneous freezing. Reductions of up to 45% in the freezing times were observed using PMB. The plateau of the temperature curve, related to the freezing time of free water, was significantly reduced using PMB, which is accepted to lead to better product quality after thawing. As the products were protected by the LDPE films as primary packaging, their appearance were not affected. The results presented in this work indicate that replacing CBB with PMB can be an excellent alternative to reduce freezing time and improve freezing homogeneity in industrial air blast tunnels, which could also be applied to other products.O congelamento de cortes de frango em túneis convectivos é normalmente realizado com o produto envolto por filmes de polietileno de baixa densidade (PEBD, embalagem primária e acondicionado em caixas de papelão (CP, embalagem secundária. O objetivo deste trabalho foi avaliar o efeito da embalagem secundária no congelamento dos cortes de frango. Para isso, compararam-se as curvas de congelamento do produto processado acondicionado em caixas metálicas perfuradas (CMP, que praticamente eliminam a resistência térmica da embalagem secundária, com as curvas de congelamento do produto nas CP

  1. Tratamento da dor em queimados

    Rodrigo José Alencar de Castro

    2013-02-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: Apesar dos avanços, ainda é observado manejo analgésico inadequado dos pacientes com queimaduras. O objetivo desta revisão foi coletar dados sobre tratamento da dor em queimados. CONTEÚDO: Foi feita revisão sobre os mecanismos de dor, avaliação do paciente com queimadura e o tratamento farmacológico e não farmacológico. CONCLUSÕES: O manejo da dor em pacientes vítimas de queimaduras ainda é um desafio por parte da equipe multiprofissional. A avaliação frequente e contínua da resposta apresentada pelo paciente é muito importante, tendo em vista os vários momentos por que passa o paciente internado em decorrência de uma queimadura, além de uma terapêutica combinada com medicações analgésicas e medidas não farmacológicas. Entender a complexidade de alterações fisiopatológicas, psicológicas e bioquímicas apresentadas por um paciente em tratamento de queimadura é o primeiro passo para alcançar o sucesso no seu manejo analgésico.

  2. The ChArMEx database

    Ferré, Hélène; Descloitres, Jacques; Fleury, Laurence; Boichard, Jean-Luc; Brissebrat, Guillaume; Focsa, Loredana; Henriot, Nicolas; Mastrorillo, Laurence; Mière, Arnaud; Vermeulen, Anne

    2013-04-01

    The Chemistry-Aerosol Mediterranean Experiment (ChArMEx, http://charmex.lsce.ipsl.fr/) aims at a scientific assessment of the present and future state of the atmospheric environment in the Mediterranean Basin, and of its impacts on the regional climate, air quality, and marine biogeochemistry. The project includes long term monitoring of environmental parameters, intensive field campaigns, use of satellite data and modelling studies. Therefore ChARMEx scientists produce and need to access a wide diversity of data. In this context, the objective of the database task is to organize data management, distribution system and services such as facilitating the exchange of information and stimulating the collaboration between researchers within the ChArMEx community, and beyond. The database relies on a strong collaboration between OMP and ICARE data centres and falls within the scope of the Mediterranean Integrated Studies at Regional And Locals Scales (MISTRALS) program data portal. All the data produced by or of interest for the ChArMEx community will be documented in the data catalogue and accessible through the database website: http://mistrals.sedoo.fr/ChArMEx. The database website offers different tools: - A registration procedure which enables any scientist to accept the data policy and apply for a user database account. - Forms to document observations or products that will be provided to the database in compliance with metadata international standards (ISO 19115-19139; INSPIRE; Global Change Master Directory Thesaurus). - A search tool to browse the catalogue using thematic, geographic and/or temporal criteria. - Sorted lists of the datasets by thematic keywords, by measured parameters, by instruments or by platform type. - A shopping-cart web interface to order in situ data files. At present datasets from the background monitoring station of Ersa, Cape Corsica and from the 2012 ChArMEx pre-campaign are available. - A user-friendly access to satellite products

  3. Criação intensiva de suínos em confinamento ou ao ar livre: estudo meta-analítico do desempenho zootécnico nas fases de crescimento e terminação e avaliação de carcaça e carne no Longissimus dorsi Intensive pig production in confinement or outdoor systems: a meta-analytical study of the production performance in the growing and finishing phases and carcass and meat evaluation from the Longissimus dorsi

    Alice Bogoni Demori

    2012-07-01

    Full Text Available Uma meta-análise foi realizada para avaliar o desempenho e a qualidade de carcaça e carne de suínos em função do sistema de alojamento nas fases de crescimento/terminação. Foram selecionadas publicações indexadas com resultados de experimentos comparando variáveis de desempenho e de pós-abate de suínos alojados em sistemas intensivos convencionais ou ao ar livre. A base de dados contemplou 27 artigos publicados entre 1997 e 2009. Ao total, foram considerados 2.985 animais e 701 médias na análise de dados. A meta-análise foi realizada através de duas análises sequenciais: gráfica e de variância-covariância. O sistema de criação de suínos ao ar livre aumentou em 9% (P0,05 pelo sistema de alojamento dos suínos. Concluiu-se que o sistema de criação influencia no desempenho dos suínos, mas não interfere nas características de carcaça e carne estudadas.A meta-analysis was carried out to study performance and characteristics of carcass and meat in pigs in function of housing system during the growing/finishing period. Indexed publications with results of experiments comparing performance and post-slaughter variables of pigs housed in outdoor or conventional intensive systems were selected. In total, 2.985 animals and 701 averages were considered in the data analysis. Meta-analysis followed two sequential analyses: graphic and variance. The outdoor productive system increased in 9% (P0.05 by the housing system. It is concluded that the housing system influences the pig performance, but does not interfere in characteristics of carcass and meat.

  4. Spectroscopic analysis of visible and near UV light emitted by Ar7+ and Ar6+ ions produced in Ar8+-He and Ar8+-H2 collisions at 120 keV

    Boduch, P.; Chantepie, M.; Hennecart, D.; Husson, X.; Kucal, H.; Lecler, D.; Stolterfoht, N.; Druetta, M.; Fawcett, B.; Wilson, M.

    1992-01-01

    A spectroscopic analysis of light emitted in the 2000-6000A wavelength range by Ar 7+ and Ar 6+ ions produced in Ar 8+ -He and Ar 8+ -H 2 collisions at 120 keV is performed. Well resolved fine structure components of 5s-5p and 5p-5d transitions in Ar VIII following single electron capture are precisely measured. Predominant lines due to double electron capture are observed. In particular, strong lines observed both in Ar 8+ -He and Ar 8+ -H 2 collisions are attributed to Ryberg transitions 3snl-3sn'l' in Ar VII. Attempts at identifications are made for the transition 3dnl-3dn'l' (n=4, 5) with the help of ab initio calculations. Photon emission cross sections for individual lines are determined from the measured data. (orig.)

  5. Emergency preparedness with Ar-41 measurement

    Kunst, Juan J.; Rodriguez, Monica; Ugarte, Ricardo; Vigile, Sebastian; Boutet, Luis; Jordan, Osvaldo; Hernandez, Daniel

    2008-01-01

    Full text: The Nuclear Regulatory Authority (ARN) of Argentina is training their intervention group in the forecast of radiological consequences in case of a radiological or nuclear accident. In this context it has begun the measurement of Ar-41 near the research reactor RA3. It is well known the Ar-41 production inside research reactor, and it has been studied like a good mean to validate atmosphere dispersion model occurrence, or to develop method to improve the estimation of the characteristic of the emission. The measurements were made in two laboratories of ARN, Gamma measurement Laboratory, and CTC (Total Body Counter) Laboratory near the research reactor RA3. The emission of Ar-41 were determined by Measurements Group of Environmental Control Division inside the research reactor. The laboratories are at SE and ESE direction from the reactor. After the passage of a cold front, the wind flown from SE, in this situation and if the reactor is operating we could detect the presence of Ar-41 in the environment. This meteorological situation can be forecast by information submitted by National Meteorological Service of Argentina (SMN) in a meteograma. To correlate and evaluate the concentration in this laboratory, first it was determined the direction and persistence of wind in the site using the forecast of the National Meteorological Service (SMN) of Argentina to establish when the detectors were irradiated, during the radiological measurements, the real time wind direction an velocities measurement were did, with a site meteorological tower. With this information and cloudiness we determined de stability class and concentration. To determine concentration we used the code Hotspot and our code SEDA developed in ARN. In this paper are present the calibration of GeH detectors, and the location of them. We present several measurements did in this experience. We analyze the capacity developed by our teams to predict changes in wind direction and concentrations

  6. K/Ar dating of diagenetic illites

    Mizusaki, A.M.P.; Anjos, S.M.C. dos; Costa, M.G.F. da; Silva, O.B. da; Kawashita, K.

    1990-01-01

    Ascertaining the potassium/argon (K/Ar) age of diagenetic illites yields important information for hydrocarbon exploration since the growth of this mineral in the pores of sandstone reservoir and oil migration are interlinked events in the diagenetic evolution of rocks. Illite growth ceases as soon as hydrocarbons completely fill in rock pores, displacing interstitial water. By providing an estimate of the period when the illite formed, K/Ar dating can indirectly tells us when hydrocarbons entered the reservoir. Samples of oil-saturated sandstones collected from Carboniferous reservoirs of the Solimoes Basin reveal a diagenetic evolution consisting predominantly of quartz, calcite, and illite overgrowths. In the present study, illite was mechanically separated by repeating a series of ultrasonic baths and ultrasonic probes followed by high-speed centrifuging. Resultant fractions were analyzed by X-ray diffractometry to measure the illite content of each sample. The separated illite material was found to be composed of illite and ordered mixed layer illite-smectite with 80% illite layers. Separated fractions were dated radiometrically by the K/Ar method. Preliminary results indicate an average age of some 200 m.y., which marks the end of the diagenetic development of the illites of this area. (author)

  7. Lifetime and spin measurements in 40Ar

    Southon, J.

    1976-01-01

    Lifetimes of levels in 40 Ar populated by the 40 Ar(p,p') reaction have been measured using the Doppler shift attenuation method with a p-γ coincidence technique. A solid argon target was used. The lifetimes determined were (in psec.): 1461 keV level, 1.95 +- 0.15; 2121 keV, >25; 2524 keV, 0.53 +- 0.06; 2893 keV, 4.4 [+2.6,-1.3]; 3208 keV, 0.27. A comprehensive set of branching ratios was also derived and the spins and parities of the 3208 and 4481 keV states were determined to be 2 + and 1 +- respectively. Some of these results suggest that 2 particle -2 hole and 4 particle - 4 hole components are strongly mixed in the low-lying positive parity states in a manner similar to the 2 particle and 4 particle - 2 hole mixing that occurs in 42 Ca. An additional lifetime measurement for the recently discovered high spin state at 3464 keV was carried out using direct electronic timing. The level was excited by the 37 Cl(α,p) reaction and was found to have a lifetime of 1.00 +- 0.03 nsec, which taken together with other evidence indicates that its spin and parity are 6 + . The E2 transition strengths of the 40 Ar 6 + - 4 + - 2 + - 0 + cascade can be simply interpreted in terms of a weak coupling model. (author)

  8. Determination of the Kwall correction factor for a cylindrical ionization chamber to measure air-kerma in 60Co gamma beams

    Laitano, R.F.; Toni, M.P.; Pimpinella, M.; Bovi, M.

    2002-01-01

    The factor K wall to correct for photon attenuation and scatter in the wall of ionization chambers for 60 Co air-kerma measurement has been traditionally determined by a procedure based on a linear extrapolation of the chamber current to zero wall thickness. Monte Carlo calculations by Rogers and Bielajew (1990 Phys. Med. Biol. 35 1065-78) provided evidence, mostly for chambers of cylindrical and spherical geometry, of appreciable deviations between the calculated values of K wall and those obtained by the traditional extrapolation procedure. In the present work an experimental method other than the traditional extrapolation procedure was used to determine the K wall factor. In this method the dependence of the ionization current in a cylindrical chamber was analysed as a function of an effective wall thickness in place of the physical (radial) wall thickness traditionally considered in this type of measurement. To this end the chamber wall was ideally divided into distinct regions and for each region an effective thickness to which the chamber current correlates was determined. A Monte Carlo calculation of attenuation and scatter effects in the different regions of the chamber wall was also made to compare calculation to measurement results. The K wall values experimentally determined in this work agree within 0.2% with the Monte Carlo calculation. The agreement between these independent methods and the appreciable deviation (up to about 1%) between the results of both these methods and those obtained by the traditional extrapolation procedure support the conclusion that the two independent methods providing comparable results are correct and the traditional extrapolation procedure is likely to be wrong. The numerical results of the present study refer to a cylindrical cavity chamber like that adopted as the Italian national air-kerma standard at INMRI-ENEA (Italy). The method used in this study applies, however, to any other chamber of the same type. (author)

  9. Sistema de aquisição de dados para equipamento de medida da permeabilidade intrínseca do solo ao ar

    Luciano Roberto da Silveira

    2011-04-01

    Full Text Available A permeabilidade intrínseca - ou simplesmente permeabilidade do solo ao ar - é uma propriedade importante para a identificação de alterações no espaço poroso do solo causadas pelas práticas de manejo, na estimativa de propriedades do solo mais difíceis e onerosas e na composição de modelos de fluxo de fluidos em solos agrícolas e em solos contaminados. O objetivo do presente estudo foi construir um sistema de aquisição de dados (módulo eletrônico e programa computacional para a medida da permeabilidade do solo ao ar em laboratório, utilizando-se materiais disponíveis no local e ferramentas computacionais de acesso livre. O sistema de aquisição de dados mostrou-se bastante preciso na determinação da permeabilidade do solo ao ar, com intervalo de confiança de 9,42 ± 0,085 μm² (95 %, para uma amostra-padrão constituída de partículas com diâmetro de 0,106 a 0,250 mm da fração areia de um Latossolo Vermelho-Amarelo textura média. A estimativa da permeabilidade do solo ao ar, considerando a viscosidade dinâmica do ar em função da temperatura, foi significativamente maior que a estimativa com valor fixo de viscosidade dinâmica em aproximadamente 20 ºC. A medição realizada em uma amostra de solo com estrutura indeformada de um Latossolo Vermelho foi tão precisa quanto à da amostra-padrão, e a estimativa da massa de água removida da amostra foi de 3,27 mg.

  10. 40Ar/ 39Ar ages and paleomagnetism of São Miguel lavas, Azores

    Johnson, Catherine L.; Wijbrans, Jan R.; Constable, Catherine G.; Gee, Jeff; Staudigel, Hubert; Tauxe, Lisa; Forjaz, Victor-H.; Salgueiro, Mário

    1998-08-01

    We present new 40Ar/ 39Ar ages and paleomagnetic data for São Miguel island, Azores. Paleomagnetic samples were obtained for 34 flows and one dike; successful mean paleomagnetic directions were obtained for 28 of these 35 sites. 40Ar/ 39Ar age determinations on 12 flows from the Nordeste complex were attempted successfully: ages obtained are between 0.78 Ma and 0.88 Ma, in contrast to published K-Ar ages of 1 Ma to 4 Ma. Our radiometric ages are consistent with the reverse polarity paleomagnetic field directions, and indicate that the entire exposed part of the Nordeste complex is of a late Matuyama age. The duration of volcanism across São Miguel is significantly less than previously believed, which has important implications for regional melt generation processes, and temporal sampling of the geomagnetic field. Observed stable isotope and trace element trends across the island can be explained, at least in part, by communication between different magma source regions at depth. The 40Ar/ 39Ar ages indicate that our normal polarity paleomagnetic data sample at least 0.1 Myr (0-0.1 Ma) and up to 0.78 Myr (0-0.78 Ma) of paleosecular variation and our reverse polarity data sample approximately 0.1 Myr (0.78-0.88 Ma) of paleosecular variation. Our results demonstrate that precise radiometric dating of numerous flows sampled is essential to accurate inferences of long-term geomagnetic field behavior. Negative inclination anomalies are observed for both the normal and reverse polarity time-averaged field. Within the data uncertainties, normal and reverse polarity field directions are antipodal, but the reverse polarity field shows a significant deviation from a geocentric axial dipole direction.

  11. 78 FR 41838 - Establishment of Class E Airspace; Colt, AR

    2013-07-12

    ...-1281; Airspace Docket No. 12-ASW-13] Establishment of Class E Airspace; Colt, AR AGENCY: Federal... at Colt, AR. Controlled airspace is necessary to accommodate new Area Navigation (RNAV) Standard... Federal Register a notice of proposed rulemaking (NPRM) to establish Class E airspace for the Colt, AR...

  12. 75 FR 29657 - Establishment of Class E Airspace; Marianna, AR

    2010-05-27

    ...-1167; Airspace Docket No. 09-ASW-33] Establishment of Class E Airspace; Marianna, AR AGENCY: Federal... for Marianna, AR to accommodate Area Navigation (RNAV) Standard Instrument Approach Procedures (SIAPs) at Marianna/Lee County Airport--Steve Edwards Field, Marianna, AR. The FAA is taking this action to...

  13. 75 FR 68416 - Establishment of Class E Airspace; Berryville, AR

    2010-11-08

    ...-0690; Airspace Docket No. 10-ASW-2] Establishment of Class E Airspace; Berryville, AR AGENCY: Federal... for Berryville, AR, to accommodate Area Navigation (RNAV) Standard Instrument Approach Procedures (SIAP) at Carroll County Airport, Berryville, AR. The FAA is taking this action to enhance the safety...

  14. 75 FR 12161 - Establishment of Class E Airspace; Marianna, AR

    2010-03-15

    ...-1167; Airspace Docket No. 09-ASW-33] Establishment of Class E Airspace; Marianna, AR AGENCY: Federal... proposes to establish Class E airspace at Marianna/Lee County Airport-Steve Edwards Field, Marianna, AR, to... operations at Marianna/Lee County Airport-Steve Edwards Field, Marianna, AR. Controlled airspace is needed...

  15. 75 FR 29656 - Amendment of Class E Airspace; Magnolia, AR

    2010-05-27

    ...-1179; Airspace Docket No. 09-ASW-35] Amendment of Class E Airspace; Magnolia, AR AGENCY: Federal... airspace for Magnolia, AR. Decommissioning of the Magnolia non-directional beacon (NDB) at Magnolia Municipal Airport, Magnolia, AR has made this action necessary to enhance the safety and management of...

  16. 75 FR 12162 - Class E Airspace; Manila, AR

    2010-03-15

    ...-1184; Airspace Docket No. 09-ASW-39] Class E Airspace; Manila, AR AGENCY: Federal Aviation... Class E airspace at Manila, AR. Decommissioning of the Manila non-directional beacon (NDB) at Manila... instrument approach procedures at Manila Municipal Airport, Manila, AR. Airspace reconfiguration is necessary...

  17. 76 FR 73505 - Establishment of Class E Airspace; Nashville, AR

    2011-11-29

    ...-0497; Airspace Docket No. 11-ASW-4] Establishment of Class E Airspace; Nashville, AR AGENCY: Federal... for Nashville, AR, to accommodate new Area Navigation (RNAV) Standard Instrument Approach Procedures... a notice of proposed rulemaking to amend Class E airspace for Nashville, AR, creating additional...

  18. 75 FR 29655 - Amendment of Class E Airspace; Batesville, AR

    2010-05-27

    ...-1177; Airspace Docket No. 09-ASW-34] Amendment of Class E Airspace; Batesville, AR AGENCY: Federal... Batesville, AR. Decommissioning of the Independence County non-directional beacon (NDB) at Batesville Regional Airport, Batesville, AR, has made this action necessary to enhance the safety and management of...

  19. 75 FR 66300 - Amendment of Class E Airspace; Searcy, AR

    2010-10-28

    ...-1182; Airspace Docket No. 09-ASW-37] Amendment of Class E Airspace; Searcy, AR AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: This action amends Class E airspace for Searcy, AR. Decommissioning of the Searcy non-directional beacon (NDB) at Searcy Municipal Airport, Searcy, AR, has made this...

  20. 75 FR 37291 - Amendment of Class E Airspace; Osceola, AR

    2010-06-29

    ...-1183; Airspace Docket No. 09-ASW-38] Amendment of Class E Airspace; Osceola, AR AGENCY: Federal... Osceola, AR. Decommissioning of the Osceola non-directional beacon (NDB) at Osceola Municipal Airport has... rulemaking to amend Class E airspace for Osceola, AR, reconfiguring controlled airspace at Osceola Municipal...

  1. 75 FR 12163 - Class E Airspace; Mountain View, AR

    2010-03-15

    ...-1181; Airspace Docket No. 09-ASW-36] Class E Airspace; Mountain View, AR AGENCY: Federal Aviation... Class E airspace at Mountain View, AR. Decommissioning of the Wilcox non-directional beacon (NDB) at... View, AR. Airspace reconfiguration is necessary due to the decommissioning of the Wilcox NDB and the...

  2. 75 FR 29654 - Amendment of Class E Airspace; Manila, AR

    2010-05-27

    ...-1184; Airspace Docket No. 09-ASW-39] Amendment of Class E Airspace; Manila, AR AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: This action amends Class E airspace for Manila, AR. Decommissioning of the Manila non-directional beacon (NDB) at Manila Municipal Airport, Manila, AR has made this...

  3. 75 FR 12165 - Class E Airspace; Batesville, AR

    2010-03-15

    ...-1177; Airspace Docket No. 09-ASW-34] Class E Airspace; Batesville, AR AGENCY: Federal Aviation... Class E airspace at Batesville, AR. Decommissioning of the Independence County non-directional beacon... for standard instrument approach procedures at Batesville Regional Airport, Batesville, AR. Airspace...

  4. A importância do controle de qualidade em serviços de hemodinâmica e cardiologia intervencionista The relevance of quality control in services of hemodynamics and interventional cardiology

    Eara de Souza Luz

    2007-02-01

    Full Text Available OBJETIVO: Avaliar o desempenho de um equipamento de raios X utilizado em radiologia intervencionista e a qualidade de imagem produzida, aplicando alguns testes de controle de qualidade. MATERIAIS E MÉTODOS: O equipamento de raios X testado foi da marca Philips (Integris H3000, do serviço de hemodinâmica de um hospital do Rio de Janeiro. Foram utilizados objetos de teste de Leeds para avaliar a qualidade da imagem, e um sistema Radcal 9015 para medições dosimétricas. RESULTADOS: Nos modos high e normal, os valores medidos das taxas de kerma no ar foram diferentes dos esperados. Em alguns casos, os valores das taxas medidas não foram afetados pelo uso de diferentes modos de magnificação. A avaliação da qualidade da imagem apresentou resultados diferentes dos valores recomendados pelas normas. Isto pode levar à obtenção de imagens de menor qualidade e ao aumento da exposição à radiação de pacientes e profissionais. CONCLUSÃO: Os resultados mostraram a importância da aplicação periódica de testes de controle de qualidade, que permitem monitorar o desempenho do equipamento e estimar a exposição dos pacientes e trabalhadores. Os resultados obtidos sugerem a necessidade de uma revisão no sistema de aquisição de imagens do equipamento.OBJECTIVE: To evaluate the performance and quality of images of a x-ray equipment utilized in interventional radiology, by means of some tests of quality control. MATERIALS AND METHODS: Measurements have been performed on a Philips Integris H3000 x-ray equipment dedicated to interventional procedures in the hemodynamics laboratory of a hospital in Rio de Janeiro, RJ, Brazil. Leeds test objects have been used to evaluate the image quality. Dosimetric measurements have been developed with a Radcal 9015 dosimetric system. RESULTS: In high and normal modes, the air kerma rates have been different from the expected results. In some cases, values have not been affected by the use of different

  5. 40Ar/39Ar and K-Ar age constraints on the timing of regional deformation, south coast of New South Wales, Lachlan Fold Belt: problems and implications

    Fergusson, C.L.; Phillips, D.

    2001-01-01

    Four slate samples from subduction complex rocks exposed on the south coast of New South Wales, south of Batemans Bay, were analysed by K-Ar and 40 Ar/ 39 Ar step-heating methods, One sample contains relatively abundant detrital muscovite flakes that are locally oblique to the regional cleavage in the rock, whereas the remaining samples appear to contain sparse detrital muscovite. Separates of detrital muscovite yielded plateau ages of 505 + 3 Ma and 513 + 3 Ma indicating that inheritance has not been eliminated by metamorphism and recrystallisation. Step-heating analyses of whole-rock chips from all four slate samples produced discordant apparent age spectra with 'saddle shapes' following young apparent ages at the lowest temperature increments. Elevated apparent ages associated with the highest temperature steps are attributed to the presence of variable quantities of detrital muscovite ( 40 Ar/ 39 Ar integrated ages of ca 455Ma, which are some 15-30 million years older than K-Ar ages for the same samples. These discrepancies suggest that the slates have also been affected by recoil loss/redistribution of 39 Ar, Ieading to anomalously old 40 Ar/ 39 Ar ages. Two other samples, from slaty tectonic melange and intensely cleaved slate, yielded average 40 Ar/ 39 Ar integrated ages of ca 424Ma, which are closer to associated mean K-Ar ages of 423 + 4Ma and 409 + 16Ma, respectively. Taking into account the potential influences of recoil loss/redistribution of 39 Ar and inheritance, the results from the latter samples suggest a maximum age of ca 440 Ma for deformation/metamorphism. The current results indicate that recoil and inheritance problems may also have affected whole-rock 40 Ar/ 39 Ar data reported from other regions of the Lachlan Fold Belt. Therefore, until these effects are adequately quantified, models for the evolution of the Lachlan Fold Belt, that are based on such whole-rock 40 Ar/ 39 Ar data, should be treated with caution. Copyright (2001) Geological

  6. Efeitos do pneumoperitônio com ar e CO2 na gasometria de suínos

    Lemos, Silvio Luis da Silveira; Vinha, Joaquim Miguel; Silva, Iandara Schettert; Novaes, Paulo André Costa; Oliveira, Maisse Fernandes; Paula, Georgette Beatriz; Rebelo, Camila Carvalho; Marinho, Marcelo Luiz

    2003-01-01

    OBJETIVO: O pneumoperitônio produz várias alterações na fisiologia humana. Algumas destas alterações, como hipercapnia e acidose, dependem ou são agravadas com o uso de CO2, tendo maior repercussão em pacientes com problema cardio-respiratório. A necessidade de uma melhor alternativa para insuflação da cavidade; a observação de que as cirurgias abertas, assim como as laparoscópicas com suspensão mecânica, são realizadas na presença de Ar ambiente; e a escassez de trabalhos testando o Ar em su...

  7. Influência da brisa terra-mar no período de saturação da umidade do ar no interior de dois seringais de cultivo em Ubatuba(SP Influence of the land-sea breese on the saturation period of the relative humidity inside two adult rubber tree plantations in Ubatuba, State of São Paulo, Brazil

    José Eduardo Macedo Pezzopane

    1996-01-01

    Full Text Available Avaliou-se, em Ubatuba(SP, a influência da brisa terra-mar no número de horas com umidade relativa igual ou superior a 90% (NHUR > 90% no interior de dois seringais [Hevea brasiliensis (Willd. ex Adr. de Juss Müell Arg.] adultos: um próximo à praia (800 m e outro distante 5.000 m. Para o período estudado, os resultados demonstraram uma redução significativa do NHUR > 90%, 50% em média, no seringal próximo à praia. A diferença ficou mais evidente, 71,4% em média, quando se analisaram apenas os dias não chuvosos, a fim de desconsiderar a saturação atmosférica devida à chuva. Os resultados deste estudo mostram que a advecção condicionada pela brisa terra-mar é fator aerodinâmico de mesoescala que interfere no início e no final da saturação da umidade atmosférica, reduzindo a duração do período de molhamento das folhas.It was studied the influence of the land-sea breese on the duration of relative humidity equal to or higher than 90% (NHUR > 90% inside two adult rubber tree plantations [Hevea brasiliensis (Willd. ex Adr. de Juss Müell Arg.]: one located near the shore (800 m and other approximately 5,000 m away. It was found a significant reduction of NHUR > 90% in the plantation near the shore. This reduction was even more evident in clear nights, without rainfall effect. It is assumed that the advection of land-sea breese interferes at the starting and final moments of the humidity saturation, decreasing the leaf wettness duration period.

  8. Cartografar é traçar um plano comum

    Virgínia Kastrup

    2013-08-01

    Full Text Available A pesquisa de campo sobre produção da subjetividade enfrenta o problema de construir conhecimento envolvendo pesquisadores e pesquisados, com territórios e semióticas singulares. Surgem questões relativas ao protagonismo dos participantes e a como traçar com eles um plano comum, garantindo o caráter participativo da pesquisa. No contexto do método da cartografia, o artigo tem como objetivo tratar do tema do comum num duplo aspecto. Num primeiro, discute o acesso ao plano comum. Com base em Gilles Deleuze e Felix Guattari, tal plano não é dito homogêneo nem reúne atores que manteriam entre si relações de identidade, mas opera comunicação entre singularidades, sendo pré-individual e coletivo. Num segundo aspecto, aponta que, enquanto pesquisa-intervenção, a cartografia se compromete com a criação de um mundo comum e heterogêneo. O artigo mostra que o traçado do comum tem como diretriz metodológica a tranversalidade e examina os procedimentos de participação, inclusão e tradução.

  9. The thermal history of the Lhasa Block, South Tibetan Plateau based on FTD and Ar-Ar dating

    Yang, T F; Lo Chong Huah; Chung, S L; Tien, R L; Xu, R; Deng, W

    1999-01-01

    Twelve basement samples were collected from South Tibet Plateau for FTD and Ar-Ar analysis to demonstrate their uplifting history since Cenozoic era. The preliminary results from different minerals with different closure temperatures, including apatite and zircon for fission-track dating, and K-feldspar, biotite for Ar-Ar dating, show that at least four stages of thermal history can be recognized in the studied area.

  10. Histone demethylase JMJD1A promotes alternative splicing of AR variant 7 (AR-V7) in prostate cancer cells.

    Fan, Lingling; Zhang, Fengbo; Xu, Songhui; Cui, Xiaolu; Hussain, Arif; Fazli, Ladan; Gleave, Martin; Dong, Xuesen; Qi, Jianfei

    2018-05-15

    Formation of the androgen receptor splicing variant 7 (AR-V7) is one of the major mechanisms by which resistance of prostate cancer to androgen deprivation therapy occurs. The histone demethylase JMJD1A (Jumonji domain containing 1A) functions as a key coactivator for AR by epigenetic regulation of H3K9 methylation marks. Here, we describe a role for JMJD1A in AR-V7 expression. While JMJD1A knockdown had no effect on full-length AR (AR-FL), it reduced AR-V7 levels in prostate cancer cells. Reexpression of AR-V7 in the JMJD1A-knockdown cells elevated expression of select AR targets and partially rescued prostate cancer cell growth in vitro and in vivo. The AR-V7 protein level correlated positively with JMJD1A in a subset of human prostate cancer specimens. Mechanistically, we found that JMJD1A promoted alternative splicing of AR-V7 through heterogeneous nuclear ribonucleoprotein F (HNRNPF), a splicing factor known to regulate exon inclusion. Knockdown of JMJD1A or HNRNPF inhibited splicing of AR-V7, but not AR-FL, in a minigene reporter assay. JMJD1A was found to interact with and promote the recruitment of HNRNPF to a cryptic exon 3b on AR pre-mRNA for the generation of AR-V7. Taken together, the role of JMJD1A in AR-FL coactivation and AR-V7 alternative splicing highlights JMJD1A as a potentially promising target for prostate cancer therapy.

  11. The thermal history of the Lhasa Block, South Tibetan Plateau based on FTD and Ar-Ar dating

    Yang, T.F.; Wang, J.R.; Lo, C.H.; Chung, S.L.; Tien, R.L.; Xu, R.; Deng, W.

    1999-01-01

    Twelve basement samples were collected from South Tibet Plateau for FTD and Ar-Ar analysis to demonstrate their uplifting history since Cenozoic era. The preliminary results from different minerals with different closure temperatures, including apatite and zircon for fission-track dating, and K-feldspar, biotite for Ar-Ar dating, show that at least four stages of thermal history can be recognized in the studied area

  12. Call for Development of New Mineral Standards for 40Ar/39Ar Dating

    Deino, A. L.; Turrin, B. D.; Renne, P. R.; Hemming, S. R.

    2015-12-01

    Age determination via the 40Ar/39Ar dating method relies on the intercomparison of measured 40Ar*/39ArK ratios of geological unknowns with those of co-irradiated mineral standards. Good analytical procedure dictates that these ratios (and the evolution of the Ar ion beams underpinning them) be as similar as practical for the greatest accuracy. Unfortunately, throughout several intervals of the geological time scale this 'best practice' cannot be achieved with existing widely used standards. Only two internationally utilized sanidine standards are available for the middle to late Cenozoic: the Alder Creek Rhyolite sanidine (ACs), at ~1.2 Ma (Turrin et al., 1994; Nomade et al., 2005), and the Fish Canyon Tuff sanidine (FCs) at ~28.2 Ma (e.g., Kuiper et al., 2008; Renne et al, 2011). The situation is even worse throughout much of the rest of the Phanerozoic, as the next oldest standard in common use is the Hb3gr hornblende standard with an age of ~1.1 Ga (Turner, 1971; Jourdan et al., 2006). We propose, as a community effort, the development a set of standards covering the entire target range of high-precision 40Ar/39Ar dating, i.e. the Phanerozoic. Their ages would be stepped in a regular fashion with no more than approximately a factor of 3 between standards, such that in the worse case the 40Ar*/39Ar ratios of standards and unknown need differ by no more than a factor of two. While somewhat arbitrary, an approximately 3 X age progression allows the entire time scale to be covered by a manageable number of standards. Anchoring the progression in the widely used ACs, FCs, and Hb3gr (in bold, below) yields the following set of suggested standard ages: 0.4, 1.2, 3.3, 9.4, 28.2, 95, 320, and 1100 Ma. A suitable standard should be highly reproducible in age at the grain-to-grain and sub-grain levels, and highly radiogenic. The mineral should be abundant and easily separated from the host rock. These criteria may be most easily achieved by focusing on sanidine phenocrysts

  13. Escala Diagnóstica Adaptativa Operacionalizada de Autorrelato - EDAO-AR: Evidências de Validade

    Elisa Medici Pizao Yoshida

    2013-04-01

    Full Text Available A Escala Diagnóstica Adaptativa Operacionalizada-Revisada (EDAO-R fornece medida da eficácia adaptativa, entendida como o grau de sucesso obtido no enfrentamento das vicissitudes da vida. Sua avaliação baseia-se em material de entrevista clínica. O estudo teve por objetivo obter evidências de validade da versão de autorrelato da EDAO-R, ou EDAO-AR. Foram desenvolvidos itens para avaliar a adequação da adaptação de dois setores da personalidade: Afetivo-Relacional (A-R e Produtividade (Pr. A amostra foi composta por 237 pacientes ambulatoriais e acompanhantes. Houve evidências de validade baseada na estrutura interna (consistência interna, análise fatorial, análise de agrupamentos e validade baseada em variáveis externas (relação entre EDAO-AR e Escala de Avaliação de Sintomas-40/EAS-40. Os resultados apontaram boa consistência interna e três dimensões para ambos os setores: foco na situação problema, foco na relação interpessoal e foco no eu. Obteve-se, conforme esperado, correlações negativas entre a EDAO-AR e EAS-40. Foram feitas sugestões para a segunda versão da escala.

  14. Application of quadrupole mass spectrometer to the 40Ar-39Ar geochronological study

    Takigami, Yutaka; Nishijima, Tadashi; Koike, Toshio; Okuma, Kouichi.

    1984-01-01

    A Quadrupole Mass Spectrometer (QMS) has commonly been used for qualitative analyses of gases in organic chemistry or for monitoring the vacuum conditions in industrial machines. No attempt has been made, however, to apply it to geochronological studies because of its disadvantages such as the difficulty in obtaining precise isotope ratios due to triangular peak shapes and poor reproducibility. On the other hand, there are advantages that a QMS is relatively inexpensive and gives a shorter scanning time for analysis compared with a sector type mass spectrometer. The latter characteristics is useful for 40 Ar/ 39 Ar geochronological studies, since it gives a lower background in the QMS and the possibility to obtain many more data from one sample in a limited time. In this study, we have tried to improve a commercial QMS at many parts, such as rf-generator, quadrupole, ionization chamber, source magnet, and so on, in order to meet the requirements to use it for geochronological studies. With the use of the improved QMS equipped with an on-line microcomputer, we could obtain Ar isotope data which are sufficiently precise for the 40 Ar/ 39 Ar geochronological studies. (author)

  15. A test of the 40Ar/39Ar age spectrum technique on some terrestrial materials

    Lanphere, M.A.; Brent, Dalrymple G.

    1971-01-01

    40Ar/39Ar age spectra were determined for 10 terrestrial rock and mineral samples whose geologic history is known from independent evidence. The spectra for six mineral and whole rock samples, including biotite, feldspar, hornblende, muscovite, and granodiorite, that have experienced post-crystallization heating did not reveal the age of crystallization in any obvious way. Minima in the spectra, however, give reasonable maximum ages for reheating and high-temperature maxima can be interpreted as minimum crystallization ages. High-temperature ages of microcline and albite that have not been reheated are approximately 10% younger than the known crystallization age. Apparently there are no domains in these feldspars that have retained radiogenic 40Ar quantitatively. Spectra from two diabase samples that contain significant quantities of excess argon might mistakenly be interpreted as spectra from reheated samples and do not give the age of emplacement. The 40Ar/39Ar age spectrum technique may be a potentially valuable tool for the study of geologic areas with complex histories, but the interpretation of age spectra from terrestrial samples seems to be more difficult than suggested by some previous studies. ?? 1971.

  16. Arsénico en el agua de bebida: un problema de salud pública Arsênio na água de beber: um problema de saúde pública

    Alexandra Galetovic Carabantes

    2003-12-01

    Full Text Available La presencia de arsénico en el ambiente es un problema de salud pública debido a que se trata de un evento de alta frecuencia que ha sido detectado en países como Argentina, Brasil, Chile, China, India, México y Taiwán, entre otros. El arsénico fue clasificado por la International Agency for Research on Cancer (IARC, como un agente carcinogénico para humanos con base en estudios epidemiológicos que relacionan la ingestión de arsénico en el agua de bebida y cáncer en la piel y estudios ocupacionales que relacionan la exposición al arsénico y cáncer de pulmón. La Organización Mundial de la Salud (OMS recomienda um valor orientador para agua de bebida de 10 mg As/L. Por su parte la Environmental Protection Agency (EPA, considerando estimativas de riesgo realizadas utilizando modelos estadísticos basados en observaciones en humanos y extrapolando los datos para concentraciones inferiores a 50 µg/L, reducirá el valor guía para arsénico en el agua de bebida de 50 µg/L para 10 µg/L. La utilización de biomarcadores permite el desarrollo de la epidemiología molecular que promete ser una herramienta que ayudará a detectar efectos tempranos en poblaciones expuestas, permitiendo la prevención de efectos nocivos considerando las características genéticas de las poblaciones.A presença de arsênio no ambiente é um problema de saúde pública por ser um evento de alta freqüência detectado em países como Argentina, Brasil, Chile, China, Índia, México e Taiwan, entre outros. O arsênio foi classificado pela Agência Internacional de Pesquisa sobre Câncer (IARC, como um agente carcinogênico para humanos com base em estudos epidemiológicos que relacionam a ingestão de arsênico na água para consumo humano e câncer na pele e estudos ocupacionais que relacionam a exposição ao arsênico e câncer no pulmão.A Organização Mundial da Saúde (OMS recomenda um valor orientador para água de beber de 10 mg As/L, enquanto que a

  17. The celecoxib derivatives AR-12 and AR-14 induce autophagy and clear prion-infected cells from prions.

    Abdulrahman, Basant A; Abdelaziz, Dalia; Thapa, Simrika; Lu, Li; Jain, Shubha; Gilch, Sabine; Proniuk, Stefan; Zukiwski, Alexander; Schatzl, Hermann M

    2017-12-14

    Prion diseases are fatal infectious neurodegenerative disorders that affect both humans and animals. The autocatalytic conversion of the cellular prion protein (PrP C ) into the pathologic isoform PrP Sc is a key feature in prion pathogenesis. AR-12 is an IND-approved derivative of celecoxib that demonstrated preclinical activity against several microbial diseases. Recently, AR-12 has been shown to facilitate clearance of misfolded proteins. The latter proposes AR-12 to be a potential therapeutic agent for neurodegenerative disorders. In this study, we investigated the role of AR-12 and its derivatives in controlling prion infection. We tested AR-12 in prion infected neuronal and non-neuronal cell lines. Immunoblotting and confocal microscopy results showed that AR-12 and its analogue AR-14 reduced PrP Sc levels after only 72 hours of treatment. Furthermore, infected cells were cured of PrP Sc after exposure of AR-12 or AR-14 for only two weeks. We partially attribute the influence of the AR compounds on prion propagation to autophagy stimulation, in line with our previous findings that drug-induced stimulation of autophagy has anti-prion effects in vitro and in vivo. Taken together, this study demonstrates that AR-12 and the AR-14 analogue are potential new therapeutic agents for prion diseases and possibly protein misfolding disorders involving prion-like mechanisms.

  18. Legacy K/Ar and 40Ar/39Ar geochronologic data from the Alaska-Aleutian Range batholith of south-central Alaska

    Koeneman, Lisa L.; Wilson, Frederic H.

    2018-04-06

    Sample descriptions and analytical data for more than 200 K/Ar and 40Ar/39Ar analyses from rocks of the Alaska-Aleutian Range batholith of south-central Alaska are reported here. Samples were collected over a period of 20 years by Bruce R. Reed and Marvin A. Lanphere (both U.S. Geological Survey) as part of their studies of the batholith.

  19. Influência da dependência energética de dosímetros termoluminescentes na medida da dose na entrada da pele em procedimentos radiográficos Influence of thermoluminescent dosimeters energy dependence on the measurement of entrance skin dose in radiographic procedures

    Mércia Liane de Oliveira

    2010-04-01

    Full Text Available OBJETIVO: O objetivo do presente trabalho foi avaliar a influência da dependência energética de materiais termoluminescentes na determinação da dose na entrada da pele de pacientes submetidos a exames radiográficos (radiologia geral, mamografia e radiologia odontológica. MATERIAIS E MÉTODOS: Três diferentes materiais termoluminescentes foram utilizados: LiF:Mg,Ti, LiF:Mg,Cu,P e CaSO4:Dy. Estes materiais foram expostos a fontes padronizadas de radiação X e gama, e a feixes clínicos de raios X. RESULTADOS: As curvas de calibração e de dependência energética foram obtidas. Todos os materiais apresentaram resposta linear em função do kerma no ar. Com relação à dependência energética, as amostras de CaSO4:Dy e LiF:Mg,Ti mostraram maior variação da resposta termoluminescente em função da energia efetiva do feixe de radiação. CONCLUSÃO: Os materiais testados mostraram desempenho adequado para a detecção da radiação X em feixes padronizados e clínicos. Embora as amostras de CaSO4:Dy e LiF:Mg,Ti apresentem dependência energética significativa no intervalo de energia considerado, este materiais podem ser utilizados para medição da dose de entrada na pele se fatores de correção apropriados forem utilizados.OBJECTIVE: This study was aimed at evaluating the influence of the energy dependence of thermoluminescent materials on the determination of entrance skin dose in patients submitted to conventional radiographic studies (general radiology, mammography and dental radiology. MATERIALS AND METHODS: Three different thermoluminescent materials were utilized: LiF:Mg,Ti, LiF:Mg,Cu,P and CaSO4:Dy. These materials were exposed to standardized sources of X and gamma radiation and clinical X-ray beams. RESULTS: Calibration and energy dependence curves were obtained. All the materials showed a linear response as a function of the air kerma. As far as energy dependence is concerned, the CaSO4:Dy and LiF:Mg,Ti samples showed the

  20. Ar + NO microwave plasmas for Escherichia coli sterilization

    Hueso, Jose L; Rico, Victor J; Cotrino, Jose; Gonzalez-Elipe, Agustin R [Instituto de Ciencia de Materiales de Sevilla, Centro Mixto CSIC-Universidad de Sevilla, Centro de Investigaciones Cientificas Isla de la Cartuja, Avda. Americo Vespucio 49, 41092 Sevilla (Spain); Frias, Jose E [Instituto de BioquImica Vegetal y FotosIntesis (IBVF-CSIC). Centro de Investigaciones CientIficas Isla de la Cartuja. Avda Americo Vespucio, 49, 41092 Sevilla (Spain)], E-mail: jhueso@icmse.csic.es

    2008-05-07

    Ar + NO microwave discharges are used for sterilization and the results are compared with additional experiments with Ar, O{sub 2} and N{sub 2}-O{sub 2} plasma mixtures. The NO{sup *} species produced in the Ar-NO mixtures remain up to long distances from the source, thus improving the sterilization efficiency of the process. E. coli individuals exposed to the Ar + NO plasma undergo morphological damage and cell lysis. Combined effects of etching (by O{sup *} and Ar{sup *} species) and UV radiation (from deactivation of NO{sup *} species) are responsible for the higher activity found for this plasma mixture. (fast track communication)

  1. Ar + NO microwave plasmas for Escherichia coli sterilization

    Hueso, Jose L; Rico, Victor J; Cotrino, Jose; Gonzalez-Elipe, Agustin R; Frias, Jose E

    2008-01-01

    Ar + NO microwave discharges are used for sterilization and the results are compared with additional experiments with Ar, O 2 and N 2 -O 2 plasma mixtures. The NO * species produced in the Ar-NO mixtures remain up to long distances from the source, thus improving the sterilization efficiency of the process. E. coli individuals exposed to the Ar + NO plasma undergo morphological damage and cell lysis. Combined effects of etching (by O * and Ar * species) and UV radiation (from deactivation of NO * species) are responsible for the higher activity found for this plasma mixture. (fast track communication)

  2. Enhancement of Ar sup 8 sup + ion beam intensity from RIKEN 18 GHz electron cyclotron resonance ion source by optimizing the magnetic field configuration

    Higurashi, Y; Kidera, M; Kase, M; Yano, Y; Aihara, T

    2003-01-01

    We successfully produced a 1.55 emA Ar sup 8 sup + ion beam using the RIKEN 18 GHz electron cyclotron resonance ion source at a microwave power of 700 W. To produce such an intense beam, we optimized the minimum magnetic field of mirror magnetic field and plasma electrode position. (author)

  3. MEIS1 functions as a potential AR negative regulator

    Cui, Liang; Li, Mingyang; Feng, Fan; Yang, Yutao; Hang, Xingyi; Cui, Jiajun; Gao, Jiangping

    2014-01-01

    The androgen receptor (AR) plays critical roles in human prostate carcinoma progression and transformation. However, the activation of AR is regulated by co-regulators. MEIS1 protein, the homeodomain transcription factor, exhibited a decreased level in poor-prognosis prostate tumors. In this study, we investigated a potential interaction between MEIS1 and AR. We found that overexpression of MEIS1 inhibited the AR transcriptional activity and reduced the expression of AR target gene. A potential protein–protein interaction between AR and MEIS1 was identified by the immunoprecipitation and GST pull-down assays. Furthermore, MEIS1 modulated AR cytoplasm/nucleus translocation and the recruitment to androgen response element in prostate specific antigen (PSA) gene promoter sequences. In addition, MEIS1 promoted the recruitment of NCoR and SMRT in the presence of R1881. Finally, MEIS1 inhibited the proliferation and anchor-independent growth of LNCaP cells. Taken together, our data suggests that MEIS1 functions as a novel AR co-repressor. - Highlights: • A potential interaction was identified between MEIS1 and AR signaling. • Overexpression of MEIS1 reduced the expression of AR target gene. • MEIS1 modulated AR cytoplasm/nucleus translocation. • MEIS1 inhibited the proliferation and anchor-independent growth of LNCaP cells

  4. Quantum treatment of the Ar-HI photodissociation dynamics

    Lopez-Lopez, Sergio; Prosmiti, Rita; Garcia-Vela, Alberto

    2004-01-01

    A wave packet simulation of the ultraviolet photolysis dynamics of Ar-HI(v=0) is reported. Cluster photodissociation is started from two different initial states, namely, the ground van der Waals (vdW) and the first excited vdW bending state, associated with the Ar-I-H and Ar-H-I isomeric forms of the system, respectively. Formation of Ar-I radical products is investigated over the energy range of the cluster absorption spectrum. It is found that the yield of bound Ar-I radical complexes is typically 90%-100% and 70%-80% for the initial states associated with the Ar-I-H and Ar-H-I isomers, respectively. This result is in agreement with the experimentally observed time-of-flight spectrum of the hydrogen fragment produced after Ar-HI photodissociation. The high Ar-I yield is explained mainly by the small amount of energy available for the radical that is converted into internal energy in the photofragmentation process, which enhances the Ar-I survival probability. Quantum interference effects manifest themselves in structures in the angular distribution of the hydrogen fragment, and in pronounced rainbow patterns in the rotational distributions of the Ar-I radical

  5. Argon defect complexes in low energy Ar irradiated molybdenum

    Veen, A. van; Buters, W.T.M.; Kolk, G.J. van der; Caspers, L.M.; Armstrong, T.R.

    1982-01-01

    Thermal desorption spectrometry has been used to study the defects created in Mo irradiated along the direction with Ar ions ranging in energy from 0.1 to 2 keV. In addition to monitoring the release of the implanted Ar, additional information has been obtained by decoration of the defects with low energy helium and subsequent monitoring of the helium release. The studies show evidence that the Ar can be trapped in both substitutional sites and in a configuration in which the Ar is associated with vacancies (ArVsub(n), n >= 2). Most of the Ar implanted at high energy is released at approx. equal to 1500 K by thermal vacancy assisted diffusion. Argon trapped closer to the surface is released at lower temperatures via at least three different surface related release mechanisms. Additional results are presented on the interaction of self interstitial atoms (introduced by 100 eV Xe bombardment) with the Ar defects. Substitutional Ar is found to convert to interstitial Ar which seems to be mobile at room temperature. The Ar-vacancy complexes are found to be reduced to substitutional Ar. The results of atomistic calculations of the release mechanisms will also be presented. (orig.)

  6. Near thermal charge transfer between Ar+2 and N2

    Holzscheiter, H.M.; Church, D.A.

    1981-01-01

    The near thermal charge transfer reaction of Ar +2 with N 2 has been studied at total pressures below 10 -7 Torr using a stored ion technique. Ar +2 ions produced by electron impact double ionization of Ar gas were selectively stored for times the order of seconds in a split-ring Penning-type ion trap. The decay with time of the initial ion sample number in a mixture of Ar and N 2 gases was fit to the sum of two exponentials, corresponding to different reaction rates for the 3 P and 1 D low-lying Ar +2 levels. The observed Ar +2 number decrease is attributed to the double-charge transfer process Ar +2 +N 2 →Ar+N 2 +2 →Ar+N + +N + in accord with recent flow-tube measurements. A rate constant for the metastable Ar +2 ( 1 D) level reaction with a value k( 1 D)=1.4 x 10 -9 cm 3 /sec is obtained, using the previously measured rate constant for the Ar +2 ( 3 P) state

  7. MEIS1 functions as a potential AR negative regulator

    Cui, Liang [Department of Urology, Chinese PLA Medical School/Chinese PLA General Hospital, Beijing 100853 (China); Department of Urology, Civil Aviation General Hospital/Civil Aviation Medical College of Peking University, Beijing 100123 (China); Li, Mingyang [Department of Gastroenterology, Nan Lou Division, Chinese PLA Medical School/Chinese PLA General Hospital, Beijing 100853 (China); Feng, Fan [Department of Pharmacy, General Hospital of Shenyang Military Command, Shenyang 110016 (China); Yang, Yutao [Beijing Institute for Neuroscience, Capital Medical University, Beijing 100069 (China); Hang, Xingyi [National Scientific Data Sharing Platform for Population and Health, Beijing 100730 (China); Cui, Jiajun, E-mail: cuijn@ucmail.uc.edu [Department of Cancer and Cell Biology, University of Cincinnati College of Medicine, Cincinnati, OH 45267 (United States); Gao, Jiangping, E-mail: jpgao@163.com [Department of Urology, Chinese PLA Medical School/Chinese PLA General Hospital, Beijing 100853 (China)

    2014-10-15

    The androgen receptor (AR) plays critical roles in human prostate carcinoma progression and transformation. However, the activation of AR is regulated by co-regulators. MEIS1 protein, the homeodomain transcription factor, exhibited a decreased level in poor-prognosis prostate tumors. In this study, we investigated a potential interaction between MEIS1 and AR. We found that overexpression of MEIS1 inhibited the AR transcriptional activity and reduced the expression of AR target gene. A potential protein–protein interaction between AR and MEIS1 was identified by the immunoprecipitation and GST pull-down assays. Furthermore, MEIS1 modulated AR cytoplasm/nucleus translocation and the recruitment to androgen response element in prostate specific antigen (PSA) gene promoter sequences. In addition, MEIS1 promoted the recruitment of NCoR and SMRT in the presence of R1881. Finally, MEIS1 inhibited the proliferation and anchor-independent growth of LNCaP cells. Taken together, our data suggests that MEIS1 functions as a novel AR co-repressor. - Highlights: • A potential interaction was identified between MEIS1 and AR signaling. • Overexpression of MEIS1 reduced the expression of AR target gene. • MEIS1 modulated AR cytoplasm/nucleus translocation. • MEIS1 inhibited the proliferation and anchor-independent growth of LNCaP cells.

  8. AR-Signaling in Human Malignancies: Prostate Cancer and Beyond

    Michael T. Schweizer

    2017-01-01

    Full Text Available In the 1940s Charles Huggins reported remarkable palliative benefits following surgical castration in men with advanced prostate cancer, and since then the androgen receptor (AR has remained the main therapeutic target in this disease. Over the past couple of decades, our understanding of AR-signaling biology has dramatically improved, and it has become apparent that the AR can modulate a number of other well-described oncogenic signaling pathways. Not surprisingly, mounting preclinical and epidemiologic data now supports a role for AR-signaling in promoting the growth and progression of several cancers other than prostate, and early phase clinical trials have documented preliminary signs of efficacy when AR-signaling inhibitors are used in several of these malignancies. In this article, we provide an overview of the evidence supporting the use of AR-directed therapies in prostate as well as other cancers, with an emphasis on the rationale for targeting AR-signaling across tumor types.

  9. The ChArMEx database

    Ferré, Helene; Belmahfoud, Nizar; Boichard, Jean-Luc; Brissebrat, Guillaume; Descloitres, Jacques; Fleury, Laurence; Focsa, Loredana; Henriot, Nicolas; Mastrorillo, Laurence; Mière, Arnaud; Vermeulen, Anne

    2014-05-01

    The Chemistry-Aerosol Mediterranean Experiment (ChArMEx, http://charmex.lsce.ipsl.fr/) aims at a scientific assessment of the present and future state of the atmospheric environment in the Mediterranean Basin, and of its impacts on the regional climate, air quality, and marine biogeochemistry. The project includes long term monitoring of environmental parameters, intensive field campaigns, use of satellite data and modelling studies. Therefore ChARMEx scientists produce and need to access a wide diversity of data. In this context, the objective of the database task is to organize data management, distribution system and services, such as facilitating the exchange of information and stimulating the collaboration between researchers within the ChArMEx community, and beyond. The database relies on a strong collaboration between OMP and ICARE data centres and has been set up in the framework of the Mediterranean Integrated Studies at Regional And Locals Scales (MISTRALS) program data portal. All the data produced by or of interest for the ChArMEx community will be documented in the data catalogue and accessible through the database website: http://mistrals.sedoo.fr/ChArMEx. At present, the ChArMEx database contains about 75 datasets, including 50 in situ datasets (2012 and 2013 campaigns, Ersa background monitoring station), 25 model outputs (dust model intercomparison, MEDCORDEX scenarios), and a high resolution emission inventory over the Mediterranean. Many in situ datasets have been inserted in a relational database, in order to enable more accurate data selection and download of different datasets in a shared format. The database website offers different tools: - A registration procedure which enables any scientist to accept the data policy and apply for a user database account. - A data catalogue that complies with metadata international standards (ISO 19115-19139; INSPIRE European Directive; Global Change Master Directory Thesaurus). - Metadata forms to document

  10. 40Ar-39Ar laser probe dating of individual clinopyroxene inclusions in Premier eclogitic diamonds

    Burgess, R.; Turner, G.; Laurenzi, M.; Harris, J.W.

    1989-01-01

    The ages of seven individual clinopyroxene inclusions in Premier diamonds of eclogitic association have been determined using the 40 Ar- 39 Ar dating technique. Syngenetic inclusions weighing between 10 and 130 μg were exposed on cleaved surfaces of the diamonds and analysed using a laser probe. The inclusion ages were found to be in the range 1111±35 to 1254±38 Ma with an average of 1185±94 Ma. The ages obtained are in good agreement with previous determinations made on aggregates of eclogitic inclusions from Premier diamonds and demonstrate the applicability of the laser probe to dating individual diamond inclusions. (orig.)

  11. Argon in hornblende, biotite and muscovite in geologic cooling - Ar-40/Ar-39-investigations

    Rittman, K.L.

    1984-01-01

    The results of the Ar-40/Ar-39 studies are discussed under the aspect of whether the age data of the minerals indicate a cooling process. The author hopes that isotope dating of minerals with different closing temperatures will describe the temperature/time history of an area in the temperature range of 600 to 200 0 C. The findings are analyzed under three aspects: How much do they contribute to the initial methodological question, what do they contribute to the regional geology of the areas investigated, and in what respects do they extent the present knowledge of the geochronological analysis, i.e. its techniques and interpretation. (orig.) [de

  12. Efeito da temperatura e velocidade do ar sobre a taxa de secagem da madeira de Pinus elliottii Engelm.

    Elio José Santini

    2010-08-01

    Full Text Available Para avaliar o efeito da temperatura e velocidade do ar sobre a taxa de secagem, peças de madeira de Pinus elliottii de 25 x 125 x 750 mm foram submetidas à secagem em estufa semi-industrial de convecção forçada. O processo foi conduzido para duas temperaturas e duas velocidades de ar e controlado por meio de um sistema computadorizado. Os resultados mostraram que a taxa de secagem tem uma relação diretamente proporcional com a temperatura, velocidade do ar e umidade da madeira. Por meio da análise de regressão múltipla detectou-se efeito estatisticamente significativo da temperatura e da velocidade do ar sobre a taxa e o tempo de secagem, com um nível de confiança de 99%. Como a importância da velocidade do ar na secagem decresce com a diminuição do teor de umidade, sugere-se, por razões de economia, mais investigações acerca das relações entre as duas variáveis durante o período de taxa de secagem decrescente.

  13. H + Ar collisions. II. Differential scattering calculations

    Neumann, H.; Le, T.Q.; van Zyl, B.

    1977-01-01

    Differential elastic scattering cross-section calculations have been made for H + Ar collisions using classical and eikonal techniques. The calculation procedures are described and compared with existing experimental data. It is shown that the angular distribution of the elastic cross section is similar to that obtained for proton production in such collisions at energies above about 200 eV. By combining the angular dependence of the computed elastic cross section with experimental measurements described in the preceding paper, absolute differential cross sections for proton production have been determined

  14. Simulating maize phenology as a function of air temperature with a linear and a nonlinear model Simulação da fenologia do milho em função da temperatura do ar por um modelo linear e um não linear

    Nereu Augusto Streck

    2008-04-01

    Full Text Available The objective of this study was to adapt a nonlinear model (Wang and Engel - WE for simulating the phenology of maize (Zea mays L., and to evaluate this model and a linear one (thermal time, in order to predict developmental stages of a field-grown maize variety. A field experiment, during 2005/2006 and 2006/2007 was conducted in Santa Maria, RS, Brazil, in two growing seasons, with seven sowing dates each. Dates of emergence, silking, and physiological maturity of the maize variety BRS Missões were recorded in six replications in each sowing date. Data collected in 2005/2006 growing season were used to estimate the coefficients of the two models, and data collected in the 2006/2007 growing season were used as independent data set for model evaluations. The nonlinear WE model accurately predicted the date of silking and physiological maturity, and had a lower root mean square error (RMSE than the linear (thermal time model. The overall RMSE for silking and physiological maturity was 2.7 and 4.8 days with WE model, and 5.6 and 8.3 days with thermal time model, respectively.O objetivo deste trabalho foi adaptar um modelo não linear (Wang e Engel - WE, para simular a fenologia do milho (Zea mays L., e avaliar esse modelo e um modelo linear (soma térmica, para estimar os estágios de desenvolvimento de uma variedade de milho cultivada em campo. Um experimento de dois anos, com sete datas anuais de semeadura cada ano, foi conduzido em Santa Maria, RS, durante os anos agrícolas 2005/2006 e 2006/2007. Foram registradas as datas de emergência, espigamento e maturação fisiológica da variedade de milho BRS Missões, em seis repetições, em cada data de semeadura. Os dados coletados no ano agrícola 2005/2006 foram usados para estimar os coeficientes dos dois modelos, e os dados coletados no ano agrícola 2006/2007 foram usados como dados independentes para avaliar os modelos. O modelo não linear (WE estimou com precisão as datas de espigamento

  15. Prostate Cancer Cells Express More Androgen Receptor (AR) Following Androgen Deprivation, Improving Recognition by AR-Specific T Cells.

    Olson, Brian M; Gamat, Melissa; Seliski, Joseph; Sawicki, Thomas; Jeffery, Justin; Ellis, Leigh; Drake, Charles G; Weichert, Jamey; McNeel, Douglas G

    2017-12-01

    Androgen deprivation is the primary therapy for recurrent prostate cancer, and agents targeting the androgen receptor (AR) pathway continue to be developed. Because androgen-deprivation therapy (ADT) has immmunostimulatory effects as well as direct antitumor effects, AR-targeted therapies have been combined with other anticancer therapies, including immunotherapies. Here, we sought to study whether an antigen-specific mechanism of resistance to ADT (overexpression of the AR) may result in enhanced AR-specific T-cell immune recognition, and whether this might be strategically combined with an antitumor vaccine targeting the AR. Androgen deprivation increased AR expression in human and murine prostate tumor cells in vitro and in vivo The increased expression persisted over time. Increased AR expression was associated with recognition and cytolytic activity by AR-specific T cells. Furthermore, ADT combined with vaccination, specifically a DNA vaccine encoding the ligand-binding domain of the AR, led to improved antitumor responses as measured by tumor volumes and delays in the emergence of castrate-resistant prostate tumors in two murine prostate cancer models (Myc-CaP and prostate-specific PTEN-deficient mice). Together, these data suggest that ADT combined with AR-directed immunotherapy targets a major mechanism of resistance, overexpression of the AR. This combination may be more effective than ADT combined with other immunotherapeutic approaches. Cancer Immunol Res; 5(12); 1074-85. ©2017 AACR . ©2017 American Association for Cancer Research.

  16. Assessment of peak skin dose in interventional cardiology: A comparison between Gafchromic film and dosimetric software em.dose.

    Greffier, J; Van Ngoc Ty, C; Bonniaud, G; Moliner, G; Ledermann, B; Schmutz, L; Cornillet, L; Cayla, G; Beregi, J P; Pereira, F

    2017-06-01

    To compare the use of a dose mapping software to Gafchromic film measurement for a simplified peak skin dose (PSD) estimation in interventional cardiology procedure. The study was conducted on a total of 40 cardiac procedures (20 complex coronary angioplasty of chronic total occlusion (CTO) and 20 coronary angiography and coronary angioplasty (CA-PTCA)) conducted between January 2014 to December 2015. PSD measurement (PSD Film ) was obtained by placing XR-RV3 Gafchromic under the patient's back for each procedure. PSD (PSD em.dose ) was computed with the software em.dose©. The calculation was performed on the dose metrics collected from the private dose report of each procedure. Two calculation methods (method A: fluoroscopic kerma equally spread on cine acquisition and B: fluoroscopic kerma is added to one air Kerma cine acquisition that contributes to the PSD) were used to calculate the fluoroscopic dose contribution as fluoroscopic data were not recorded in our interventional room. Statistical analyses were carried out to compare PSD Film and PSD em.dose . The PSD Film median (1st quartile; 3rd quartile) was 0.251(0.190;0.336)Gy for CA-PTCA and 1.453(0.767;2.011)Gy for CTO. For method-A, the PSD em.dose was 0.248(0.182;0.369)Gy for CA-PTCA and 1.601(0.892;2.178)Gy for CTO, and 0.267(0.223;0.446)Gy and 1.75 (0.912;2.584)Gy for method-B, respectively. For the two methods, the correlation between PSD Film and PSD em.dose was strong. For all cardiology procedures investigated, the mean deviation between PSD Film and PSD em.dose was 3.4±21.1% for method-A and 17.3%±23.9% for method-B. The dose mapping software is convenient to calculate peak skin dose in interventional cardiology. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  17. Microbial contamination of central supply systems for medical air Contaminação microbiana dos sistemas centrais de abastecimento de ar medicinal

    Carolina Machado Andrade

    2003-11-01

    Full Text Available There are many standards and recommendations for breathing air quality associated with respiratory protection equipment, but little has been done regarding the possible microbial contamination of medical air. The present study demonstrates quantitatively and qualitatively that pipelines might be incriminated as source of microbial contamination of compressed and synthetic air for medical use. Air samples were drawn into an especially pressure-resistant device and the bacterial and fungi contents were identified after growth on agar plates. The bacterial flora isolated from peripheral air outlets was virtually the same as that found in the central air-generating installations, consisting of a mixture of pathogens and normal skin bacteria. Several factors contributing to microbial contamination of medical air are mentioned and preventive measures are discussed.Existem vários padrões e recomendações para a qualidade do ar respirável relacionado aos equipamentos de proteção respiratória, mas pouco tem sido feito em relação a uma possível contaminação microbiana do ar medicinal. O presente trabalho demonstra quantitativa e qualitativamente que as linhas de ar estão relacionadas à contaminação microbiológica do ar comprimido e ar sintético para uso medicinal. Amostras de ar foram coletadas por um equipamento especialmente resistente a pressão, e o conteúdo bacteriano e fúngico foi identificado após crescimento em placa. A flora bacteriana isolada tanto dos sistema periféricos de ar foi virtualmente a mesma encontrada nas instalações centralizadas, sendo uma mistura de patógenos e bactérias normais da pele. Vários fatores contribuintes para a contaminação microbiana do ar medicinal e medidas preventivas são discutidas.

  18. Light Curve Variations of AR Lacertae

    Il-Seong Nha

    1991-12-01

    Full Text Available Sixteen unitary Light curves of AR Lac in B and V are made at Yonsei University Observatory in the period of 1980-1988. Some overview findings of light variations are made. (1 The light variations outside eclipse follow none of the wave migration patterns reported by previous investigators. (2 Complicated shapes outside eclipse are apparently much reduced in the light curves of 1983-1984. This suggests that, in the future, AR Lac has a chance to attain a normal state with mo complicated interactions. (3 The depths of the primary and the secondary mid-eclipses are changing year-to-year. (4 The K0 star, the larger component, has brightened by 0.m14 V, while the G2 star has shown a fluctuation of about 0.m05 in V. (5 The B-V values at primary mid-eclipse have no correlation with the depth variations. (6 Independently of the increase of maximum brightness, the B-V colors in the non-eclipsed phases changed slightly over the years.

  19. High-resolution 40Ar/39Ar chronology of multiple intrusion igneous complexes

    Foland, K. A.; Chen, J.-F.; Linder, J. S.; Henderson, C. M. B.; Whillans, I. M.

    1989-06-01

    The Mount Brome complex of the Monteregian province of southern Quebec, Canada, consits of several major intrusions ranging compositionally from gabbro to syenite. The relative ages of these intrusives have been investigated with high-resolution 40Ar/39Ar analyses, including a specially designed irradiation configuration to cancel the effects of fluence gradients. Small yet distinct apparent age differences are observed. While a number of analytical and geological factors could be proposed to explain the small variations, evaluation of these suggests the age differences reflect those in emplacement times. The gabbro and nepheline diorite were emplaced within a short span 123.1 Ma ago. Generally more evolved lithologies (biotite monzodiorite, pulaskite, nordmarkite) appear to have been emplaced within a restricted interval 1.4±0.3 Ma later. Whole-rock Rb-Sr systematics do not give acceptable isochrons because of significant scatter interpreted to reflect initial 87Sr/86Sr heterogeneities resulting from crustal contamination. Considering the variations in initial ratio, the Rb-Sr data are consistent with the 40Ar/39Ar age.

  20. 40Ar-39Ar dating of hornfels dredged near the Japan trench

    Takigami, Yutaka; Fujioka, Kantaro

    1989-01-01

    During the KH 81-3 Cruise of the R/V Hakuho-Maru, biotite-bearing hornfelses were dredged from the landward slope of the Japan Trench. Bulk sample and separated biotite were dated by the 40 Ar- 39 Ar method and they showed 40 Ar- 39 Ar ages of 28.9±1.4 Ma and 28.5±1.4 Ma, respectively. This would indicate that biotite was formed at about 29 Ma by the thermal metamorphism which might have related with some magmatic activity. In this magmatic activity was caused by the subducting oceanic plate in the similar conditions at present, it seems to have occurred at a place too close to the present trench axis. This discrepancy could be explained by such processes as the change of the angle of the subducting plate, the moving of the trench axis by tectonic erosion and so on. However, more age data are required to solve this discrepancy. (author)

  1. The 40Ar/39Ar and K/Ar dating of lavas from the Hilo 1-km core hole, Hawaii Scientific Drilling Project

    Sharp, W.D.; Turrin, B.D.; Renne, P.R.; Lanphere, M.A.

    1996-01-01

    Mauna Kea lava flows cored in the HilIo hole range in age from <200 ka to about 400 ka based on 40Ar/39Ar incremental heating and K-Ar analyses of 16 groundmass samples and one coexisting plagioclase. The lavas, all subaerially deposited, include a lower section consisting only of tholeiitic basalts and an upper section of interbedded alkalic, transitional tholeiitic, and tholeiitic basalts. The lower section has yielded predominantly complex, discordant 40Ar/39Ar age spectra that result from mobility of 40Ar and perhaps K, the presence of excess 40Ar, and redistribution of 39Ar by recoil. Comparison of K-Ar ages with 40Ar/39Ar integrated ages indicates that some of these samples have also lost 39Ar. Nevertheless, two plateau ages of 391 ?? 40 and 400 ?? 26 ka from deep in the hole, combined with data from the upper section, show that the tholeiitic section accumulated at an average rate of about 7 to 8 m/kyr and has an mean recurrence interval of 0.5 kyr/flow unit. Samples from the upper section yield relatively precise 40Ar/39Ar plateau and isotope correlation ages of 326 ?? 23, 241 ?? 5, 232 ?? 4, and 199 ?? 9 ka for depths of -415.7 m to -299.2 m. Within their uncertainty, these ages define a linear relationship with depth, with an average accumulation rate of 0.9 m/kyr and an average recurrence interval of 4.8 kyr/flow unit. The top of the Mauna Kea sequence at -280 m must be older than the plateau age of 132 ?? 32 ka, obtained for the basal Mauna Loa flow in the corehole. The upward decrease in lava accumulation rate is a consequence of the decreasing magma supply available to Mauna Kea as it rode the Pacific plate away from its magma source, the Hawaiian mantle plume. The age-depth relation in the core hole may be used to test and refine models that relate the growth of Mauna Kea to the thermal and compositional structure of the mantle plume.

  2. 40Ar/39Ar age of the Rotoiti Breccia and Rotoehu Ash, Okataina Volcanic Complex, New Zealand, and identification of heterogeneously distributed excess 40Ar in supercooled crystals

    Flude, Stephanie; Storey, Michael

    2016-01-01

    Co-magmatic granitoid clasts erupted as part of the Rotoiti Ignimbrite (Rotoehu Tephra) contain euhedral K-feldspar and biotite crystals that protrude into miarolytic cavities and show textural evidence for growth in super-cooled conditions and are thus interpreted as growing during eruption. 40Ar...... that appear to be largely unaffected by excess 40Ar. This population gives a statistically robust weighted mean age of 47.4 ± 1.5 ka (1σ, n = 13) and an indistinguishable inverse isochron age of 50 ± 3 ka for this historically difficult to date eruption. The weighted mean age is significantly younger than...... previous age estimates of the Rotoiti eruption obtained by K/Ar and 40Ar/39Ar dating of bracketing lavas, but is indistinguishable from recent 14C and (U–Th)/He dates and estimates based on orbital tuning and sedimentation rates constrained by 14C ages....

  3. Métodos clássicos de protecção de sistemas elevatórios contra o golpe de aríete

    Mendes, Luís Filipe Martins

    2011-01-01

    Dissertação para obtenção do Grau de Mestre em Engenharia do Ambiente, perfil Engenharia Sanitária A ocorrência de regimes transitórios, em particular do golpe de aríete e subsequente propagação de ondas de pressão, em sistemas elevatórios de água e águas residuais, é um acontecimento normal e frequente, que acompanha qualquer alteração nas suas condições normais de funcionamento. As circunstâncias mais violentas, associadas ao golpe de aríete, normalmente, resultam do corte de energia ...

  4. Structural, K-Ar and 40Ar-39Ar age studies of adularia K-feldspars from the Lizard Complex, England

    Halliday, A.N.; Mitchell, J.G.

    1976-01-01

    Conventional K-Ar analyses of fifteen adularia feldspars from the Lizard Complex yield ages between 181+-2 Ma and 220+-3 Ma (with one exception from Holseer Cove yielding an age of 156+-3 Ma). The feldspars are dominantly monoclinic but most contain a minor but constant proportion of triclinic material with variable triclinicity. An inverse correlation exists between triclinicity and K-Ar age interpreted as representing argon loss related to the structural state. Extrapolation of the data to zero triclinicity indicates a true age of 210-220 Ma. 40 Ar- 39 Ar stepwise degassing analyses yield plateau ages related to the K-Ar ages and not the crystallization age. The results can be explained in terms of postcrystallization Al-Si ordering resulting in argon loss from lattice sites which under normal diffusion conditions requires a range of activation energies. The Holseer Cove sample is monoclinic and an 40 Ar- 39 Ar stepheating analysis suggests a later crystallization at 160-170 Ma. Neither primary crystallization nor spontaneous ordering through time explain the origin of the triclinic adularia. It is suggested that ordering has been induced by the passage of low-temperature alkaline solutions at a subsequent point in geological time. Argon loss by ordering could explain the low ages found using both K-Ar and 40 Ar- 39 Ar stepheating methods when applied to feldspars in general. The 210-220 Ma, and 160-170 Ma hydrothermal events affected much of southwest England and are probably related to major geotectonic movements in western Europe. (Auth.)

  5. Androgen Receptor-Mediated Growth Suppression of HPr-1AR and PC3-Lenti-AR Prostate Epithelial Cells.

    Young-Chae Kim

    Full Text Available The androgen receptor (AR mediates the developmental, physiologic, and pathologic effects of androgens including 5α-dihydrotestosterone (DHT. However, the mechanisms whereby AR regulates growth suppression and differentiation of luminal epithelial cells in the prostate gland and proliferation of malignant versions of these cells are not well understood, though they are central to prostate development, homeostasis, and neoplasia. Here, we identify androgen-responsive genes that restrain cell cycle progression and proliferation of human prostate epithelial cell lines (HPr-1AR and PC3-Lenti-AR, and we investigate the mechanisms through which AR regulates their expression. DHT inhibited proliferation of HPr-1AR and PC3-Lenti-AR, and cell cycle analysis revealed a prolonged G1 interval. In the cell cycle, the G1/S-phase transition is initiated by the activity of cyclin D and cyclin-dependent kinase (CDK complexes, which relieve growth suppression. In HPr-1AR, cyclin D1/2 and CDK4/6 mRNAs were androgen-repressed, whereas CDK inhibitor, CDKN1A, mRNA was androgen-induced. The regulation of these transcripts was AR-dependent, and involved multiple mechanisms. Similar AR-mediated down-regulation of CDK4/6 mRNAs and up-regulation of CDKN1A mRNA occurred in PC3-Lenti-AR. Further, CDK4/6 overexpression suppressed DHT-inhibited cell cycle progression and proliferation of HPr-1AR and PC3-Lenti-AR, whereas CDKN1A overexpression induced cell cycle arrest. We therefore propose that AR-mediated growth suppression of HPr-1AR involves cyclin D1 mRNA decay, transcriptional repression of cyclin D2 and CDK4/6, and transcriptional activation of CDKN1A, which serve to decrease CDK4/6 activity. AR-mediated inhibition of PC3-Lenti-AR proliferation occurs through a similar mechanism, albeit without down-regulation of cyclin D. Our findings provide insight into AR-mediated regulation of prostate epithelial cell proliferation.

  6. Etching properties of BLT films in CF4/Ar plasma

    Kim, Dong Pyo; Kim, Kyoung Tae; Kim, Chang Il

    2003-01-01

    CF 4 /Ar plasma mass content and etching rate behavior of BLT thin films were investigated in inductively coupled plasma (ICP) reactor as functions of CF 4 /Ar gas mixing ratio, rf power, and dc bias voltage. The variation of relative volume densities for F and Ar atoms were measured by the optical emission spectroscopy (OES). The etching rate as functions of Ar content showed the maximum of 803 A/min at 80 % Ar addition into CF 4 plasma. The presence of maximum etch rate may be explained by the concurrence of two etching mechanisms such as physical sputtering and chemical reaction. The role of Ar ion bombardment includes destruction of metal (Bi, La, Ti)-O bonds as well as support of chemical reaction of metals with fluorine atoms

  7. Ar-37 in the Atmospheric and Sub-Soil Gases

    Purtschert, R.; Raghoo, L.S.

    2015-01-01

    On-site inspection of the radioactive noble gas isotope 37Ar is a definitive and unambiguous indicator of an underground nuclear explosion. 37Ar is produced underground by neutron activation of calcium by the reaction 40Ca(n,α)37Ar. In the atmosphere, 37Ar is produced by the spallation reaction 40Ar(n,4n)37Ar. Periodic measurements over the last six years on air collected in Bern revealed a background level in the order of 1-5 mBq/m 3 air in agreement with former findings and theoretical calculations. Those calculations also indicated that the intrusion of stratospheric air masses may lead to elevated tropospheric 37Ar concentrations up to 8-10 mBq/m 3 air. Selected samples taken up to now in the vicinity of nuclear power plants revealed no significant deviation from the natural background. In order to distinguish between natural and artificially elevated 37Ar the location-specific 37Ar activity range in soils, rocks and the atmosphere were identified. From CARIBIC flights, a passenger aircraft with a special air freight container filled with scientific equipment in the cargo compartment, tropospheric air samples were analyzed for 37Ar and 85Kr. The natural 37Ar production in soils and the rock basement underlying the alluvium is investigated by means of in situ measurements of different isotopes, theoretical calculations and irradiation experiments on selected rock samples. This will help resolve the temporal evolution and/or constancy of the natural 37Ar background and allow for an interpretation in terms of the identification of clandestine nuclear explosions. (author)

  8. Cross sections of the 36Ar(d,α)34mCl, 40Ar(d,α)38Cl, and 40Ar(d,p)41Ar nuclear reactions below 8.4 MeV.

    Engle, J W; Severin, G W; Barnhart, T E; Knutson, L D; Nickles, R J

    2012-02-01

    We have measured the cross section for production of the medically interesting isotope (34m)Cl, along with (38)Cl and (41)Ar, using deuteron bombardments of (36)Ar and (40)Ar below 8.4 MeV. ALICE/ASH analytical codes were employed to determine the shape of nuclear excitation functions, and experiments were performed using the University of Wisconsin tandem electrostatic accelerator to irradiate thin targets of argon gas. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Cross Sections of the 36Ar(d,α)34mCl, 40Ar(d,α)38Cl and 40Ar(d,p)41Ar Nuclear Reactions below 8.4 MeV

    Engle, J W; Severin, G W; Barnhart, T E; Knutson, L D; Nickles, R J

    2011-01-01

    We have measured the cross section for production of the medically interesting isotope 34mCl, along with 38Cl and 41Ar, using deuteron bombardments of 36Ar and 40Ar below 8.4 MeV. ALICE/ASH analytical codes were employed to determine the shape of nuclear excitation functions, and experiments were performed using the University of Wisconsin tandem electrostatic accelerator to irradiate thin targets of argon gas. PMID:22041299

  10. Progress on using deuteron-deuteron fusion generated neutrons for 40Ar/39Ar sample irradiation

    Rutte, Daniel; Renne, Paul R.; Becker, Tim; Waltz, Cory; Ayllon Unzueta, Mauricio; Zimmerman, Susan; Hidy, Alan; Finkel, Robert; Bauer, Joseph D.; Bernstein, Lee; van Bibber, Karl

    2017-04-01

    We present progress on the development and proof of concept of a deuteron-deuteron fusion based neutron generator for 40Ar/39Ar sample irradiation. Irradiation with deuteron-deuteron fusion neutrons is anticipated to reduce Ar recoil and Ar production from interfering reactions. This will allow dating of smaller grains and increase accuracy and precision of the method. The instrument currently achieves neutron fluxes of ˜9×107 cm-2s-1 as determined by irradiation of indium foils and use of the activation reaction 115In(n,n')115mIn. Multiple foils and simulations were used to determine flux gradients in the sample chamber. A first experiment quantifying the loss of 39Ar is underway and will likely be available at the time of the presentation of this abstract. In ancillary experiments via irradiation of K salts and subsequent mass spectrometric analysis we determined the cross-sections of the 39K(n,p)39Ar reaction at ˜2.8 MeV to be 160 ± 35 mb (1σ). This result is in good agreement with bracketing cross-section data of ˜96 mb at ˜2.45 MeV and ˜270 mb at ˜4 MeV [Johnson et al., 1967; Dixon and Aitken, 1961 and Bass et al. 1964]. Our data disfavor a much lower value of ˜45 mb at 2.59 MeV [Lindström & Neuer, 1958]. In another ancillary experiment the cross section for 39K(n,α)36Cl at ˜2.8 MeV was determined as 11.7 ± 0.5 mb (1σ), which is significant for 40Ar/39Ar geochronology due to subsequent decay to 36Ar as well as for the determination of production rates of cosmogenic 36Cl. Additional experiments resolving the cross section functions on 39K between 1.5 and 3.6 MeV are on their way using the LICORNE neutron source of the IPN Orsay tandem accelerator. Results will likely be available at the time of the presentation of this abstract. While the neutron generator is designed for fluxes of ˜109 cm-2s-1, arcing in the sample chamber currently limits the power—straightforwardly correlated to the neutron flux—the generator can safely be run at. Further

  11. Electron relaxation properties of Ar magnetron plasmas

    Xinjing, CAI; Xinxin, WANG; Xiaobing, ZOU

    2018-03-01

    An understanding of electron relaxation properties in plasmas is of importance in the application of magnetrons. An improved multi-term approximation of the Boltzmann equation is employed to study electron transport and relaxation properties in plasmas. Elastic, inelastic and nonconservative collisions between electrons and neutral particles are considered. The expressions for the transport coefficients are obtained using the expansion coefficients and the collision operator term. Numerical solutions of the matrix equations for the expansion coefficients are also investigated. Benchmark calculations of the Reid model are presented to demonstrate the accuracy of the improved multi-term approximation. It is shown that the two-term approximation is generally not accurate enough and the magnetic fields can reduce the anisotropy of the velocity distribution function. The electron relaxation properties of Ar plasmas in magnetrons for various magnetic fields are studied. It is demonstrated that the energy parameters change more slowly than the momentum parameters.

  12. Sensibility of different wheat varieties (strains) to Ar+ implantation

    Cui Huanhu; Jing Hua; Ma Aiping; Kang Xiuli; Yang Liping; Huang Mingjing; Ma Buzhou; Shanxi Academy of Agricultural Sciences, Taiyuan

    2005-01-01

    The sensibility of different wheat varieties (strains) to Ar + implantation was studied. The results showed that the survival rate of 21 wheat varieties (strains) at the dose of 6 x 10 16 Ar + /cm 2 could be divided into five groups: surplus sensitive varieties (strains), sensitive varieties (strains), transitional varieties (strains), obtuse varieties (strains) and surplus obtuse varieties (strains). The sensibility of wheat varieties (strains) to Ar + injection is high-moisture-fertility wheat varieties (strains) > medium-moisture-fertility wheat varieties (strains) > dry land wheat varieties (strains). The study has provided theoretical basis in induced mutation medial lethal dose of different wheat varieties (strains) to Ar + implantation. (authors)

  13. Important comments on KERMA factors and DPA cross-section data in ACE files of JENDL-4.0, JEFF-3.2 and ENDF/B-VII.1

    Konno, Chikara; Tada, Kenichi; Kwon, Saerom; Ohta, Masayuki; Sato, Satoshi

    2017-09-01

    We have studied reasons of differences of KERMA factors and DPA cross-section data among nuclear data libraries. Here the KERMA factors and DPA cross-section data included in the official ACE files of JENDL-4.0, ENDF/B-VII.1 and JEFF-3.2 are examined in more detail. As a result, it is newly found out that the KERMA factors and DPA cross-section data of a lot of nuclei are different among JENDL-4.0, ENDF/B-VII.1 and JEFF-3.2 and reasons of the differences are the followings: 1) large secondary particle production yield, 2) no secondary gamma data, 3) secondary gamma data in files12-15 mt = 3, 4) mt = 103-107 data without mt = 600 s-800 s data in file6. The issue 1) is considered to be due to nuclear data, while the issues 2)-4) seem to be due to NJOY. The ACE files of JENDL-4.0, ENDF/B-VII.1 and JEFF-3.2 with these problems should be revised after correcting wrong nuclear data and NJOY problems.

  14. Tibetan tectonics from 40Ar/39Ar analysis of a single K-feldspar sample

    Richter, F.M.; Lovera, O.M.; Harrison, T.M.; Copeland, P.

    1991-01-01

    40 Ar/ 39 Ar data on an alkali feldspar sample from the Quxu pluton, Gangdese batholith, southern Tibet, allow a detailed assessment of unroofing and uplift history between 35 and 18 Ma. The 39 Ar Arrhenius plot for this sample shows departures from a linear relationship between the effective diffusion parameter, log(D/r 2 ), and reciprocal temperature, which we interpret to be the result of a distribution of distinct diffusion-domain sizes. We use an alternative way of plotting the Arrhenius data that exhibits domain size versus cumulative % 39 Ar released during step heating. The 40 Ar/ 39 Ar age spectrum of the sample has features, such as local age plateaus, that are most easily explained in terms of the distinctive closure age of particular domains. The fact that the same distribution of diffusion-domain sizes explains both the Arrhenius data and the age spectrum is an indication that the diffusion properties operating in the laboratory are those of the sample while it was in its natural environment. Modelling of the age spectrum with a distribution of domain sizes results in the recovery of a continuous cooling-history segment rather than a single time-temperature datum. We demonstrate the robustness of the cooling-curve determination by showing the large misfits to the age spectrum that arise from relatively small changes in the cooling history. The best-fit cooling curve for the Quxu sample shows a decreasing rate of cooling in the time interval 35-18 Ma, followed by a very rapid cooling beginning at about 18 Ma. We have used a thermal model for the conductive cooling of an unroofing pluton to estimate the rate of unroofing required to explain the Quxu cooling curve, and find that in the 35-20 Ma time interval, the primary control of the thermal evolution is the conductive loss of magmatic heat with little or no unroofing (unroofing rates of approximately 0.05 mm/yr) followed by a brief period (<5 Ma) of very rapid unroofing with rates of order 2 mm

  15. Avaliação do teor de cafeína em folhas e grãos de acessos de café arábica Evaluation of the caffeine content in leaves and grains of arabica coffee accessions

    Alexsandro Lara Teixeira

    2012-03-01

    Full Text Available O presente trabalho teve como objetivo identificar, dentro do banco de germoplasma do estado de Minas Gerais, acessos de Coffea arabica L. com baixos teores de cafeína e verificar a existência de correlação entre o teor de cafeína dos grãos e de folhas ainda no estádio de mudas, viabilizando a prática da seleção precoce. Foram utilizados 75 acessos de café (cultivares, híbridos e alguns genótipos selvagens oriundos do banco de germoplasma de café do Estado de Minas Gerais. Para estudo da correlação foram utilizados oito cultivares no delineamento de blocos casualizados com três repetições. Avaliaram-se os teores de cafeína presentes nos grãos e no terceiro e quarto par de folhas verdadeiras. Seis acessos apresentaram teores de cafeína nos grãos menores que 0,88%. Correlações significativas para teor de cafeína foram observadas entre o terceiro (0,69 e quarto par de folhas (0,92 e os grãos. Foram identificados acessos com teores reduzidos de cafeína e boa produtividade de grãos, podendo ser utilizados como genitores em programas de melhoramento. Verificou-se que é possível realizar a seleção precoce para teor de cafeína, em plantas de cafeeiro ainda no estádio de mudas, por meio da avaliação do quarto par de folhas.The aim of this study was to identify, within the germplasm bank of the Minas Gerais state, Coffea arabica L. accessions with low levels of caffeine and check the correlation between grain and leaves in seedling stage, making possible the practice of early selection. Seventy-five coffe accessions (cultivars, hybrids and several wild genotypes were evaluated from the coffee germplasm bank of the Minas Gerais state. In the correlation study, eight cultivars were used on randomized complete block design with three replications. Were evaluated the caffeine levels in the grains and the third and fourth pair of true leaves. Six accessions had caffeine levels in grains smaller than 0.88%. Was also detected

  16. Evaluation of <em>HER2em> Gene Amplification in Breast Cancer Using Nuclei Microarray <em>in em>S>itu em>Hybridization

    Xuefeng Zhang

    2012-05-01

    Full Text Available Fluorescence<em> em>>in situ em>hybridization (FISH assay is considered the “gold standard” in evaluating <em>HER2/neu (HER2em> gene status. However, FISH detection is costly and time consuming. Thus, we established nuclei microarray with extracted intact nuclei from paraffin embedded breast cancer tissues for FISH detection. The nuclei microarray FISH (NMFISH technology serves as a useful platform for analyzing <em>HER2em> gene/chromosome 17 centromere ratio. We examined <em>HER2em> gene status in 152 cases of invasive ductal carcinomas of the breast that were resected surgically with FISH and NMFISH. <em>HER2em> gene amplification status was classified according to the guidelines of the American Society of Clinical Oncology and College of American Pathologists (ASCO/CAP. Comparison of the cut-off values for <em>HER2em>/chromosome 17 centromere copy number ratio obtained by NMFISH and FISH showed that there was almost perfect agreement between the two methods (κ coefficient 0.920. The results of the two methods were almost consistent for the evaluation of <em>HER2em> gene counts. The present study proved that NMFISH is comparable with FISH for evaluating <em>HER2em> gene status. The use of nuclei microarray technology is highly efficient, time and reagent conserving and inexpensive.

  17. Arsenic phytoextraction and hyperaccumulation by fern species Fitoextração e hiperacumulação de arsênio por espécies de samambaias

    Maria Isidoria Silva Gonzaga

    2006-02-01

    Full Text Available Arsenic (As is an ubiquitous trace metalloid found in all environmental media. Its presence at elevated concentrations in soils derives from both anthropogenic and natural inputs. Arsenic is a toxic and carcinogenic element, which has caused severe environmental and health problem worldwide. Technologies currently available for the remediation of arsenic-contaminated sites are expensive, environmentally disruptive, and potentially hazardous to workers. Phytoextraction, a strategy of phytoremediation, uses plants to clean up contaminated soils and has been successfully applied to arsenic contaminated soils. It has the advantage of being cost-effective and environmentally friendly. A major step towards the development of phytoextraction of arsenic-impacted soils is the discovery of the arsenic hyper accumulation in ferns, first in Pteris vittata, which presented an extraordinary capacity to accumulate 2.3% arsenic in its biomass. Another fern, Pityrogramma calomelanos was found to exhibit the same hyperaccumulating characteristics. After that, screening experiments have revealed that the Pteris genus is really unique in that many species have the potential to be used in phytoextraction of arsenic. In general, these plants seem to have both constitutive and adaptive mechanisms for accumulating or tolerating high arsenic concentration. In the past few years, much work has been done to understand and improve the hyperaccumulating capability of these amazing plants. In particular, the field of molecular biology seems to hold the key for the future of the phytoremediation.O arsênio e um metalóide traço encontrado basicamente em todos os ambientes. Elevadas concentrações de arsênio no solo podem acontecer naturalmente devido ao intemperismo de rochas ricas em arsênio, como também de atividades antropogênicas. O arsênio é um elemento tóxico e cancerígeno. Em muitas partes do mundo, a contaminação pelo arsênio tem causado problemas

  18. Implementation of the method air-kerma product area in KAP camera calibration with reference qualities of X-ray series at the SSDL RQR of Mexico

    Cejudo, Jesus; Tovar, Victor M.

    2013-01-01

    The X-Ray machines, at a reference laboratory for the instrument calibration in diagnostic radiology, should compliance with the ISO requirements. Sometimes there is not available as much laboratories as needed in Latin American countries. So this project shows the KAP ionization chamber implementation method using the TRS-457 radiation quality from the IAEA at the SSDL of Mexico. The KAP instruments calibration method consists in doing a substitution comparison using a standard reference with traceability to a primary laboratory and a transmission-monitoring chamber that measures the number of photons of the X-ray primary beam. A KAP chamber calibration requires a special array that consists in collocating the chamber in two different positions of its calibration process. Then, with air kerma-area product coefficient together with a corrected electrometer measure at referential conditions, the patient dosimetry magnitudes are calculated. The dosimetry necessity at hospitals always will be in function of possessing a highly reliable calibration coefficient chamber for making these measures. That dosimetry results will help in reducing the total or partial irradiation emitted to the human body of the patient. This is how stochastic risks will be lessened due to diagnostic studies. The purpose of this project is to have a synergy with calibration for making known that the SSDL of Mexico has the technical capacity to act as a link between primary standard dosimetry laboratories and the ionizing radiation equipment users who require that their KAP chamber have traceability from the primary standard to the user. (author)

  19. APMP/TCRI key comparison report of measurement of air kerma for medium-energy x-rays (APMP.RI(I)-K3)

    Lee, J.H.; Hwang, W.S.; Kotler, L.H.; Webb, D.V.; Buermann, L.; Burns, D.T.; Takeyeddin, M.; Shaha, V.V.; Srimanoroth, S.; Meghzifene, A.; Hah, S.H.; Chun, K.J.; Kadni, T.B.; Takata, N.; Msimang, Z.

    2008-01-01

    The APMP/TCRI Dosimetry Working Group performed the APMP.RI(I)-K3 key comparison of measurement of air kerma for medium-energy x-rays (100 kV to 250 kV) between 2000 and 2003. In total, 11 institutes took part in the comparison, among which 8 were APMP member laboratories. Two commercial cavity ionization chambers were used as transfer instruments and circulated among the participants. All the participants established the 100 kV, 135 kV, 180 kV and 250 kV x-ray beam qualities equivalent to those of the BIPM. The results showed that the maximum difference between the participants and the BIPM in the medium-energy x-ray range, evaluated using the comparison data of the linking laboratories ARPANSA and PTB, is less than 1.4%. The degrees of equivalence between the participants are presented and this comparison confirms the calibration capabilities of the participating laboratories. (authors)

  20. APMP/TCRI key comparison report of measurement of air kerma for medium-energy x-rays (APMP.RI(I)-K3)

    Lee, J.H.; Hwang, W.S. [Institute of Nuclear Energy Research, Longtan, Taiwan (China); Kotler, L.H.; Webb, D.V. [Australian Radiation Protection and Nuclear Safety Agency, Yallambie (Australia); Buermann, L. [Physikalisch Technische Bundesanstalt, Braunschweig (Germany); Burns, D.T. [Bureau International de Poids et Mesures, 92 - Sevres (France); Takeyeddin, M. [Atomic Energy Commission, Damascus (Syrian Arab Republic); Shaha, V.V. [Bhabha Atomic Research Centre, Mumbai (India); Srimanoroth, S. [Department of Medical Sciences, Nonthaburi (Thailand); Meghzifene, A. [International Atomic Energy Agency, Vienna (Austria); Hah, S.H.; Chun, K.J. [Korea Research Institute of Standards and Science, Yusong (Korea, Republic of); Kadni, T.B. [Malaysian Nuclear Agency, Kajang (Malaysia); Takata, N. [National Metrology Institute of Japan, Tsukuba (Japan); Msimang, Z. [National Metrology Institute of South Africa, Pretoria (South Africa)

    2008-10-15

    The APMP/TCRI Dosimetry Working Group performed the APMP.RI(I)-K3 key comparison of measurement of air kerma for medium-energy x-rays (100 kV to 250 kV) between 2000 and 2003. In total, 11 institutes took part in the comparison, among which 8 were APMP member laboratories. Two commercial cavity ionization chambers were used as transfer instruments and circulated among the participants. All the participants established the 100 kV, 135 kV, 180 kV and 250 kV x-ray beam qualities equivalent to those of the BIPM. The results showed that the maximum difference between the participants and the BIPM in the medium-energy x-ray range, evaluated using the comparison data of the linking laboratories ARPANSA and PTB, is less than 1.4%. The degrees of equivalence between the participants are presented and this comparison confirms the calibration capabilities of the participating laboratories. (authors)

  1. Experimental system to measure excitation cross-sections by electron impact. Measurements for ArI and ArII

    Blanco, F.; Sanchez, J.A.; Aguilera, J.A.; Campos, J.

    1989-01-01

    An experimental set-up to measure excitation cross-section of atomic and molecular levels by electron impact based on the optical method is reported. We also present some measurements on the excitation cross-section for ArI 5p'(1/2)0 level, and for simultaneous ionization and excitation of Ar leading to ArII levels belonging to the 3p 4 4p and 3p 4 4d configurations. (Author)

  2. A New Natural Lactone from <em>Dimocarpus> <em>longan> Lour. Seeds

    Zhongjun Li

    2012-08-01

    Full Text Available A new natural product named longanlactone was isolated from <em>Dimocarpus> <em>longan> Lour. seeds. Its structure was determined as 3-(2-acetyl-1<em>H>-pyrrol-1-yl-5-(prop-2-yn-1-yldihydrofuran-2(3H-one by spectroscopic methods and HRESIMS.

  3. An 40 Ar- 39 Ar study of the Cape Verde hot spot

    Holm, Paul Martin; Grandvuinet, Tanja; Wilson, James Richard

    2008-01-01

    The 40Ar-39Ar analyses of 28 groundmass separates from volcanic rocks from the islands of Santiago, Sal, and São Vicente, Cape Verde archipelago, are presented. The new age data record the volcanic evolution for Santiago from 4.6 to 0.7 Ma, for Sal from around 15 to 1.1 Ma, and for São Vicente from...... Cretaceous age for limestones deposited on the seafloor and later uplifted. The Cape Verde Rise is indicated to have fully formed in the early Miocene around 22 Ma, accompanied by the initial alkaline volcanism. Considerable volcanism on Sal, Boa Vista, and Maio took place in the Miocene and Pliocene...

  4. Acoustic resonance spectroscopy (ARS): ARS300 operations manual, software version 2.01

    NONE

    1996-07-25

    Acoustic Resonance Spectroscopy (ARS) is a nondestructive evaluation technology developed at the Los Alamos National Laboratory. The ARS technique is a fast, safe, and nonintrusive technique that is particularly useful when a large number of objects need to be tested. Any physical object, whether solid, hollow, or fluid filled, has many modes of vibration. These modes of vibration, commonly referred to as the natural resonant modes or resonant frequencies, are determined by the object`s shape, size, and physical properties, such as elastic moduli, speed of sound, and density. If the object is mechanically excited at frequencies corresponding to its characteristic natural vibrational modes, a resonance effect can be observed when small excitation energies produce large amplitude vibrations in the object. At other excitation frequencies, i.e., vibrational response of the object is minimal.

  5. Laser-fusion 40Ar/39Ar Ages of Darwin Impact Glass

    Lo, Ching-Hua; Howard, Kieren T.; Chung, Sun-Lin; Meffre, Sebastien

    2002-11-01

    Three samples of Darwin Glass, an impact glass found in Tasmania, Australia at the edge of the Australasian tektite strewn field were dated using the 40Ar/39Ar single-grain laser fusion technique, yielding isochron ages of 796-815 ka with an overall weighted mean of 816 ± 7 ka. These data are statistically indistinguishable from those recently reported for the Australasian tektites from Southeast Asia and Australia (761-816 ka; with a mean weighted age of 803 ± 3 ka). However, considering the compositional and textural differences and the disparity from the presumed impact crater area for Australasian tektites, Darwin Glass is more likely to have resulted from a distinct impact during the same period of time.

  6. Optical characteristics of a RF DBD plasma jet in various {Ar}/ {O}_{2}Ar/O2 mixtures

    Falahat, A.; Ganjovi, A.; Taraz, M.; Ravari, M. N. Rostami; Shahedi, A.

    2018-02-01

    In this paper, using the optical emission spectroscopy (OES) technique, the optical characteristics of a radiofrequency (RF) plasma jet are examined. The Ar/O2 mixture is taken as the operational gas and, the Ar percentage in the Ar/O2 mixture is varied from 70% to 95%. Using the optical emission spectrum analysis of the RF plasma jet, the excitation temperature is determined based on the Boltzmann plot method. The electron density in the plasma medium of the RF plasma jet is obtained by the Stark broadening of the hydrogen Balmer H_{β }. It is mostly seen that, the radiation intensity of Ar 4p→ 4s transitions at higher argon contributions in Ar/O2 mixture is higher. It is found that, at higher Ar percentages, the emission intensities from atomic oxygen (O) are higher and, the line intensities from the argon atoms and ions including O atoms linearly increase. It is observed that the quenching of Ar^{*} with O2 results in higher O species with respect to O2 molecules. In addition, at higher percentages of Ar in the Ar/O2 mixture, while the excitation temperature is decreased, the electron density is increased.

  7. 40Ar/39Ar dating and paleo-magnetism of traps from Ethiopia, Deccan and Siberia

    Hofmann, C.

    1997-01-01

    Recent studies have shown that major flood basalt provinces have been emplaced as short events (∼ 1 Myr), more or less synchronous with climatic crises and mass extinctions. We present new geochronologic ( 40 Ar/ 39 Ar) and magneto-stratigraphic results for the Ethiopian traps, one of the last remaining flood basalts for which little of such data were available. The ages obtained in a 2000 m thick section are indistinguishable. Moreover, magneto-stratigraphy reveals a simple 3-chron reverse-normal-reverse sequence. Although magnetic chrons cannot be yet unambiguously identified, there is more likelihood for the normal sub-chron in the main basaltic pile to correspond to 11N, supporting a brief duration (less than 1.5 Ma). The Ethiopian traps erupted near 30 Ma at or near the time of the cold and dry climate, major Antarctic ice sheet advance, and the largest sea-level drop in the Tertiary. Bhandari et al. (GRL, 1995) have discovered inter-traps sediments with a triple iridium anomaly in a series of seven basaltic lava flows in the Kutch area of the North Western Deccan traps of India. Plagioclases from three flows above the iridium bearing sediments yield 39 Ar/ 40 Ar plateau ages near 65.0 Ma: these flows have unambiguously reversed magnetic polarity interpreted as chron 29R. As a preliminary summary, evidence of the KTB asteroid impact is confirmed in the Deccan traps, showing that they are coeval events in a general sense (in a Ma long window) though clearly with vastly different time constants. This is compatible with paleontologic evidence of two scales of extinctions, one quasi-instantaneous and the other on the order of 10 5 to 10 6 yrs. Clearly, the impact cannot have caused trap eruptions. On the other hand, the exact age and significance of the lower flows more altered remains to be analyzed further as they pertained to the much debated question of duration of Deccan trap volcanism. (author)

  8. Existe sujeito em Michel Maffesoli?

    Marli Appel da Silva

    2010-06-01

    Full Text Available Este ensaio discute a concepção de sujeito na abordagem teórica de Michel Maffesoli. As ideias desse autor estão em voga em alguns meios acadêmicos no Brasil e são difundidas por algumas mídias de grande circulação nacional. Entretanto, ao longo de suas obras, os pressupostos que definem quem é o sujeito maffesoliano se encontram pouco clarificados. Portanto, para alcançar o objetivo a que se propõe, este ensaio desenvolve uma análise da epistemologia e da ontologia maffesoliana com a finalidade de compreender as origens dos pressupostos desse autor, ou seja, as teorias e os autores em que Maffesoli se baseou para desenvolver uma visão de sujeito. Com essa compreensão, pretende-se responder à questão: existe sujeito na abordagem teórica de Maffesoli.

  9. Spatial autocorrelation method using AR model; Kukan jiko sokanho eno AR model no tekiyo

    Yamamoto, H; Obuchi, T; Saito, T [Iwate University, Iwate (Japan). Faculty of Engineering

    1996-05-01

    Examination was made about the applicability of the AR model to the spatial autocorrelation (SAC) method, which analyzes the surface wave phase velocity in a microtremor, for the estimation of the underground structure. In this examination, microtremor data recorded in Morioka City, Iwate Prefecture, was used. In the SAC method, a spatial autocorrelation function with the frequency as a variable is determined from microtremor data observed by circular arrays. Then, the Bessel function is adapted to the spatial autocorrelation coefficient with the distance between seismographs as a variable for the determination of the phase velocity. The result of the AR model application in this study and the results of the conventional BPF and FFT method were compared. It was then found that the phase velocities obtained by the BPF and FFT methods were more dispersed than the same obtained by the AR model. The dispersion in the BPF method is attributed to the bandwidth used in the band-pass filter and, in the FFT method, to the impact of the bandwidth on the smoothing of the cross spectrum. 2 refs., 7 figs.

  10. A poética da tradução em Walter Benjamin e Haroldo de Campos

    Luciene Guimarães de Oliveira

    2005-04-01

    Full Text Available Este ensaio visa traçar um paralelo entre a poética da tradução de Walter Benjamin, em “A Tarefa do Tradutor”, e a de Haroldo de Campos, poeta, tradutor, e crítico brasileiro em sua teoria da tradução.

  11. Reference Gene Selection in the Desert Plant <em>Eremosparton songoricuem>m>

    Dao-Yuan Zhang

    2012-06-01

    Full Text Available <em>Eremosparton songoricum em>(Litv. Vass. (<em>E. songoricumem> is a rare and extremely drought-tolerant desert plant that holds promise as a model organism for the identification of genes associated with water deficit stress. Here, we cloned and evaluated the expression of eight candidate reference genes using quantitative real-time reverse transcriptase polymerase chain reactions. The expression of these candidate reference genes was analyzed in a diverse set of 20 samples including various <em>E. songoricumem> plant tissues exposed to multiple environmental stresses. GeNorm analysis indicated that expression stability varied between the reference genes in the different experimental conditions, but the two most stable reference genes were sufficient for normalization in most conditions.<em> EsEFem> and <em>Esα-TUB> were sufficient for various stress conditions, <em>EsEF> and <em>EsACT> were suitable for samples of differing germination stages, and <em>EsGAPDH>and <em>Es>UBQ em>were most stable across multiple adult tissue samples. The <em>Es18Sem> gene was unsuitable as a reference gene in our analysis. In addition, the expression level of the drought-stress related transcription factor <em>EsDREB2em>> em>verified the utility of<em> E. songoricumem> reference genes and indicated that no single gene was adequate for normalization on its own. This is the first systematic report on the selection of reference genes in <em>E. songoricumem>, and these data will facilitate future work on gene expression in this species.

  12. A Framework for Designing Collaborative Learning Environments Using Mobile AR

    Cochrane, Thomas; Narayan, Vickel; Antonczak, Laurent

    2016-01-01

    Smartphones provide a powerful platform for augmented reality (AR). Using a smartphone's camera together with the built in GPS, compass, gyroscope, and touch screen enables the real world environment to be overlaid with contextual digital information. The creation of mobile AR environments is relatively simple, with the development of mobile AR…

  13. Influence of Ar addition on ozone generation in nonthermal plasmas

    Chen, Hsin Liang; Lee, How Ming; Chen, Shiaw Huei; Wei, Ta Chin; Chang, Moo Been

    2010-01-01

    Inconsistency regarding the influence of Ar addition on ozone generation in a corona discharge has been found in relevant studies. Unlike in the literature to date, a dielectric barrier discharge (DBD) reactor is adopted in this study. In addition to clarifying whether using Ar as an additive would lead to different types of behavior in a DBD and a corona discharge, this study is also motivated to explore the possible causes leading to the inconsistency. The experimental results show that adding Ar into the O 2 plasma would lead to the same influence on ozone generation in the DBD and corona discharge. Moreover, all types of controversial behavior caused by Ar addition reported in the relevant literature are observed in this study as well, indicating that the results of this study are comprehensive enough to interpret the inconsistency. By examining the experimental results in detail, it is found that the controversial influences of Ar addition on ozone generation were found using different assumptions. At a fixed applied voltage, the ozone generation might increase as the Ar concentration is increased, which results from a higher discharge power. Nevertheless, for a certain specific input energy (the ratio of discharge power to gas flow rate), the ozone concentration is lower as the Ar concentration is increased. Therefore, adding Ar is not a good way to enhance ozone generation from an economic point of view.

  14. A phase one AR/C system design

    Kachmar, Peter M.; Polutchko, Robert J.; Matusky, Martin; Chu, William; Jackson, William; Montez, Moises

    1991-01-01

    The Phase One AR&C System Design integrates an evolutionary design based on the legacy of previous mission successes, flight tested components from manned Rendezvous and Proximity Operations (RPO) space programs, and additional AR&C components validated using proven methods. The Phase One system has a modular, open architecture with the standardized interfaces proposed for Space Station Freedom system architecture.

  15. Electron temperatures of inductively coupled Cl2-Ar plasmas

    Fuller, N.C.M.; Donnelly, Vincent M.; Herman, Irving P.

    2002-01-01

    Trace rare gases optical emission spectroscopy has been used to measure the electron temperature, T e , in a high-density inductively coupled Cl 2 -Ar plasma at 18 mTorr as function of the 13.56 MHz radio frequency power and Ar fraction. Only the Kr and Xe emission lines were used to determine T e , because of evidence of radiation trapping when the Ar emission lines were also used for larger Ar fractions. At 600 W (10.6 W cm-2), T e increases from ∼4.0±0.5 eV to ∼6.0±2.0 eV as the Ar fraction increases from 1% to 96%. In the H (inductive, bright) mode, T e , for a 'neat' chlorine plasma (including 1% of each He/Ne/Ar/Kr/Xe) increases only slightly from ∼3.8 to 4.0 eV as power increases from 450 to 750 W. This increase is much larger for larger Ar fractions, such as from ∼4.0 to 7.3 eV for 78% Ar. Most of these effects can be understood using the fundamental particle balance equation

  16. AR Expression in Breast Cancer CTCs Associates with Bone Metastases.

    Aceto, Nicola; Bardia, Aditya; Wittner, Ben S; Donaldson, Maria C; O'Keefe, Ryan; Engstrom, Amanda; Bersani, Francesca; Zheng, Yu; Comaills, Valentine; Niederhoffer, Kira; Zhu, Huili; Mackenzie, Olivia; Shioda, Toshi; Sgroi, Dennis; Kapur, Ravi; Ting, David T; Moy, Beverly; Ramaswamy, Sridhar; Toner, Mehmet; Haber, Daniel A; Maheswaran, Shyamala

    2018-04-01

    Molecular drivers underlying bone metastases in human cancer are not well understood, in part due to constraints in bone tissue sampling. Here, RNA sequencing was performed of circulating tumor cells (CTC) isolated from blood samples of women with metastatic estrogen receptor (ER) + breast cancer, comparing cases with progression in bone versus visceral organs. Among the activated cellular pathways in CTCs from bone-predominant breast cancer is androgen receptor (AR) signaling. AR gene expression is evident, as is its constitutively active splice variant AR-v7. AR expression within CTCs is correlated with the duration of treatment with aromatase inhibitors, suggesting that it contributes to acquired resistance to endocrine therapy. In an established breast cancer xenograft model, a bone-tropic derivative displays increased AR expression, whose genetic or pharmacologic suppression reduces metastases to bone but not to lungs. Together, these observations identify AR signaling in CTCs from women with bone-predominant ER + breast cancer, and provide a rationale for testing androgen inhibitors in this subset of patients. Implications: This study highlights a role for the AR in breast cancer bone metastasis, and suggests that therapeutic targeting of the AR may benefit patients with metastatic breast cancer. Mol Cancer Res; 16(4); 720-7. ©2018 AACR . ©2018 American Association for Cancer Research.

  17. 37Ar monitoring techniques and on-site inspection system

    Duan Rongliang; Chen Yinliang; Li Wei; Wang Hongxia; Hao Fanhua

    2001-01-01

    37 Ar is separated, purified and extracted from air sample with a low temperature gas-solid chromatographic purifying method, prepared into a radioactive measurement source and its radioactivity is measured with a proportional counter. Based on the monitoring result, a judgement can be made if an nuclear explosion event has happened recently in a spectabilis area. A series of element techniques that are associated the monitoring of the trace element 37 Ar have been investigated and developed. Those techniques include leaked gas sampling, 37 Ar separation and purification, 37 Ar radioactivity measurement and the on-site inspection of 37 Ar. An advanced 37 Ar monitoring method has been developed, with which 200 liters of air can be treated in 2 hours with sensitivity of 0.01 Bq/L for 37 Ar radioactivity measurement. A practical 37 Ar On-site Inspection system has been developed. This research work may provide technical and equipment support for the verification protection, verification supervision and CTBT verification

  18. PROJETO DE UM CONTROLADOR PROPORCIONAL-INTEGRAL PARA O SISTEMA DE CONTROLE DE QUALIDADE DO AR E DE UM NOVO SISTEMA DE CONTROLE HVAC

    Millene Caroline Albino de Oliveira

    2015-09-01

    Full Text Available Uma sala do Perlstein Hall, da Illinois Institute of Techonology, (Chicago, IL, USA possui um sistema de aquecimento, ventilação e ar condicionado (em inglês – HVAC equipado com um sensor de gás carbônico, cujo intuito é regular diretamente a qualidade do ar e assegurar que a sala esteja em condições aceitáveis. Este procedimento, porém, pode colocar uma carga extra no sistema HVAC e aumentar o consumo de energia. Desta forma, o objetivo principal do trabalho foi o desenvolvimento e a aplicação de uma estratégia de controle de temperatura e concentração de CO2 para o sistema em questão, utilizando um controlador Proporcional-Integral (PI. Dados coletados em testes realizados na sala foram utilizados para a estimação dos parâmetros das funções de transferência e dos controladores. Inicialmente, os controladores foram testados separadamente e, em seguida, em conjunto. Pode-se observar que o controlador PI obteve bons resultados, apesar do overshoot e oscilações do sistema já observados pela literatura, conseguindo atingir o set point desejado de temperatura de 70°F e de concentração de CO2 de 150 ppm. Palavras-chave: HVAC, Controle, controlador PI.

  19. 40Ar/39Ar geochronology of the El Teniente porphyry copper deposit

    Maksaev, V; Munizaga, F; McWilliams, M; Thiele, K; Arevalo, A; Zuniga, P; Floody, R

    2001-01-01

    breccias. Phyllic alteration primarily occurs as quartz-sericite haloes of quartz-sulfide-sulfate veinlets within the perimeter of the orebody, and slightly overprints potassic alteration. Propylitic alteration occurs largely peripheral to ore-grade rock. The relatively restricted development of phyllic alteration and the occurrence of the central breccia conflict with the classic porphyry copper model of Lowell and Gilbert (1970), but El Teniente may be regarded as a 'variation on a theme' of the classic model, as suggested by Gustafson and Hunt (1975). The exceedingly large size of the El Teniente deposit, coupled with its apparently young mineralization age prompted us to initiate a systematic 40 Ar/ 39 Ar study whose goals are to determine the age(s) of the hydrothermal event(s) that produced such a remarkable copper concentration and ultimately to estimate the duration of the hydrothermal activity at El Teniente. This is particularly relevant to an understanding of the processes that formed super-giant high-grade copper deposits in the Chilean Andes and elsewhere. We report here 32 total fusion 40 Ar/ 39 Ar ages from sericite and biotite from different lithologic units of El Teniente and five step-heating 40 Ar- 39 Ar ages of samples previously dated using conventional K-Ar methods (Cuadra, 1986) (au)

  20. Androgen Receptor (AR) Physiological Roles in Male and Female Reproductive Systems: Lessons Learned from AR-Knockout Mice Lacking AR in Selective Cells1

    Chang, Chawnshang; Lee, Soo Ok; Wang, Ruey-Sheng; Yeh, Shuyuan; Chang, Ta-Min

    2013-01-01

    ABSTRACT Androgens/androgen receptor (AR) signaling is involved primarily in the development of male-specific phenotypes during embryogenesis, spermatogenesis, sexual behavior, and fertility during adult life. However, this signaling has also been shown to play an important role in development of female reproductive organs and their functions, such as ovarian folliculogenesis, embryonic implantation, and uterine and breast development. The establishment of the testicular feminization (Tfm) mouse model exploiting the X-linked Tfm mutation in mice has been a good in vivo tool for studying the human complete androgen insensitivity syndrome, but this mouse may not be the perfect in vivo model. Mouse models with various cell-specific AR knockout (ARKO) might allow us to study AR roles in individual types of cells in these male and female reproductive systems, although discrepancies are found in results between labs, probably due to using various Cre mice and/or knocking out AR in different AR domains. Nevertheless, no doubt exists that the continuous development of these ARKO mouse models and careful studies will provide information useful for understanding AR roles in reproductive systems of humans and may help us to develop more effective and more specific therapeutic approaches for reproductive system-related diseases. PMID:23782840